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CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a Continuation of U.S. patent application Ser. No. 10/470,579, filed Sep. 4, 2002, to which the benefit of priority is claimed and the entirety of which is incorporated herein by reference.
FIELD OF THE INVENTION
The present invention relates to the field of transmitting real time content over IP multicast networks using only unidirectional transmission from a server to a client without content requests from the client to the server. The invention uses emulation processes at the client and server to permit support of unidirectional transmission.
BACKGROUND OF THE INVENTION
An Internet Protocol (IP) specifies the format of packets, also called datagrams, that are to be broadcast and the addressing scheme. The transmission of a single (the same) message to a select group of recipients is called a multicast. Transmission of the message to only one recipient is called a unicast transmission. A system and method currently exists for enabling UDP (User Datagram Protocol) unicast transmissions over IP multicast networks. UDP is a connectionless protocol which is part of the TCP/IP protocol suite. TCP/IP is the Transmission Control Protocol that enables two hosts to establish a connection and exchange streams of data. Unlike TCP/IP, UDP/IP provides very few error recovery services, offering instead a direct/fast way to send and receive datagrams over an IP network. It is used primarily for broadcasting messages over a network. A UDP unicast transmission is considered to be a communication session involving two hosts, a client and a server. In a typical scenario, the client contacts the server requesting the transmission of the content of a file. The content can be any type of data in any form, such as desired files, or streaming data such as audio and video. As a response, the server sends the content in form of a stream of UDP datagrams to the client. A UDP datagram consists of a UDP+IP header and data.
The client is responsible for maintaining the session alive by periodically sending an appropriate message to the server, such as a “heart beat”, or repetitive, type signal that reiterates the client's continued interest in receiving the transmission and confirms the client availability to receive content from the server.
FIG. 1 illustrates how the existing technology works. This shows a classical configuration with a Server host 100 communicating with a Client host 120 over an IP network 110 . The network 110 is typically the Internet, an Intranet or any other network supporting the TCP/IP protocol suite. As shown in FIG. 2 , the Server host 100 is hosting a Server Process 220 for communicating with a Client Process 230 hosted on the Client host 120 following an application protocol based on UDP. The term Process means a conventional application program, or task, that here is executed by each of the Server and Client. The client process is the program (or the player) responsible as well for data consuming or displaying as for maintaining alive the communication session with the server. the server process is the program responsible to manage and distribute the requested data. All of this is conventional in the art. For example, the application protocol, or Process, typically can be a streaming protocol or any other real time protocol that implements a message flow. Examples of such a protocol are Microsoft Media Server protocol (MMS), RSTP as used by Real Networks, Xing Technologies XDMA protocol or RTP real time data protocol delivering real time information of any type.
As seen in FIG. 2 , starting from the top and moving downward, in a typical scenario the message content flow is initiated by the Client 120 sending a request message REQ to the Server 100 indicating the desire to receive specific content and, for that purpose, specifying the IP address of the Client host 120 and the local port on which data is expected to be received. This message has the effect of establishing a session at application level between the Server Process 220 and Client Process 230 . The Server Process 220 accepts the request by sending the desired content in a series of DATA messages to the Client Process 230 .
In order to maintain the session alive, the Client Process 230 periodically sends a “heart beat” message signal HB to the Server Process 220 for the purpose of reassuring the Server about its availability and interest in to continue to receive the specific content. The time interval between two successive heart beat messages depends on the specific client-server application protocol. The Server Process 220 is configured such that if it does not receive a HB message in the expected time frame, it will stop sending DATA messages to the Client Process 230 , thereby terminating the communication session.
Once all of the content has been completely transferred, i.e., the last DATA message has been sent from the Server to the Client, the Server Process 220 may send a CLOSE message to the Client Process 230 , this for actively indicating that the session is terminated. Alternatively, the Client Process 230 , in the absence of receiving DATA messages within a given time frame, will imply that either the transmission is complete or the connection to the Server Process 220 has been lost. Similarly, a Client wishing to interrupt the session instructs the Client Process 230 to send an ABORT message to the Server Process 220 or can simply stop sending HB messages.
FIG. 3 illustrates a typical scenario of how components on the Server 100 and Client 120 communicate. The Server Process 220 has a unique name associated with it which translates into a corresponding network-wide address. The translation procedure is carried out by a process known as the “domain name server” (DNS) on request of the Client Process 230 . The resulting network-wide address of the Server Process 220 consists of two parts: the network-wide IP address of the Server host 100 and a local port number locally associated to the Server Process 220 .
The operation of translating a domain name into a network-wide IP address is necessary only if the Server host 100 is known by domain name and not by IP address. Once the Client Process 230 knows the network-wide address of the Server Process 220 , it is ready to initiate the communication. For that purpose, the Client Process 230 sends a message REQ to the Server Process 220 according to the protocol described above. An REQ message is typically sent by the Client 110 over a reliable transport control protocol 240 , e.g., TCP, in order to increase the probability of successfully establishing a communication session with the Server 100 .
Whenever a system has been designed to operate under less stringent requirements, the Client Process 230 can send the same REQ message over a transport protocol such as UDP, which is less reliable than, for example, TCP/IP, i.e., no data packet checking and/or redundancy. The user datagram protocol offers only a minimal transport service without guarantee of datagram delivery. It gives applications direct access to the datagram service of the IP layer. UDP is used by applications that do not require the level of service of TCP or that wish to use communications services (e.g., multicast or broadcast delivery) not available from TCP. UDP is almost a null protocol. The only service it provides over IP are checksumming of data and multiplexing by port number. Therefore, an application program running over UDP must deal directly with end-to-end communication problems that a connection-oriented protocol would have handled, e.g., retransmission for reliable delivery, packetization and reassembly, flow control, congestion avoidance, etc., when these are required. The fairly complex conventionally accomplished coupling between IP and TCP will be mirrored in the coupling between UDP and many applications using UDP. By default, a streaming program use, UDP to send data, TCP/IP or HTTP being too slow for it. A streaming application can allow a small data loss; this would not be even noticed from an end-user. Therefore, it is correct that UDP can be used when less stringent requirements.
The heart beat messages can be sent using a more reliable transport protocol since, as described above, HB messages are vital to the existence of the communication session. Alternatively, and depending on the Server Process tolerance, HB messages also may be sent over the unreliable type transport protocol. FIG. 3 does not show how CLOSE and ABORT messages are exchanged. These message types are preferably sent using a reliable transport protocol.
It should be noted how the described message flow requires the existence of a communication channel that allows the Client Host to communicate with the Server Host, a so called return channel. While this is a valid assumption for many wired networks, it may not be technically feasible or economically acceptable for satellite network or terrestrial broadcast networks. These types of networks typically implement only a forward communication path (Server to Client) and do not support a return channel that allows receiving devices to send information from the Client back to the Server. In order to support bidirectional services, service providers sometimes combine unidirectional wireless networks with wired network, for the purpose of complementing the existing forward link with the necessary return link. This approach increases the complexity and the costs of the implemented solution to a level that may discourage the service provider from adopting it.
The system shown in FIGS. 1-3 works well when only a few Clients are simultaneously requesting content from the same Server. Unfortunately, depending on the Server configuration, once the maximum number of connected Clients is reached, the quality of the service provided can degrade rapidly. This degradation is typically caused by at least one of the following reasons:
1. Server scalability: the Server is asked to generate multiple streams of content at the same time. Depending on the Server configuration and resources, the Server throughput may be limited to a quantity less than the effective throughput necessary to satisfy requests from a number of Clients.
2. Bandwidth consumption: the amount bandwidth B necessary to satisfy multiple parallel requests of content from the same Server increases as a linear function of the bandwidth b of one content transmission and the number N of requesting clients (B˜b*N). Depending on the network topology and resources available this amount of bandwidth required to satisfy multiple requests for content may exceed the overall bandwidth available for or allocated to this kind of transmission.
Moreover, the message flow described above requires the existence of a communication link from the Client to the Server, a so called return channel. While this requirement is typically satisfied in wired networks, existence of such a communication link may not be a valid assumption for unidirectional networks like satellite or terrestrial broadcast networks.
In the past, client-server applications that included unicast transmission capabilities, such as described above, had to be reengineered in order to take advantage of multicast or unidirectional networks. Various multicast capable applications designed around an open architecture exist on the market, such as Real System G2, Microsoft Windows Media, etc., but do not support unidirectional transmissions
The re-engineering task typically requires a more or less large investment of resources depending on the complexity of the application. It also increases the time required to place an existing application on the market. As a consequence, not all unicast applications have been modified to support multicast transmissions on unidirectional networks. Also, none of the above-listed systems can be used to enable an application designed around a unicast protocol to take advantage of a multicast environment without a re-engineering effort and its corresponding costs being applied to the application.
SUMMARY OF THE INVENTION
This invention relates to a system and method to overcome the problems of Server scalability and bandwidth consumption by enabling unicast transmissions over a unidirectional network and eliminating the need of a return channel. In the practice of the invention, a client emulation process and one or more server emulation processes are introduced respectively between the original Server Process and Client Process. The new emulation components act to encapsulate the UDP datagrams of the unicast stream within a multicast transport protocol, route this multicast traffic to a plurality of receiving Clients and finally recreate the original unicast stream on the side of each of the multiple Clients before sending it to the client application process of a targeted Client.
The present invention makes it possible to deploy a client-server application designed around a connection-less application protocol, such as UDP, on a multicast network. In particular, the application can be deployed on the multicast network without reengineering work, thereby reducing costs and the time required to bring an application to market.
Moreover, the invention also makes it possible to deploy the same application on a unidirectional network, i.e., on a network that does not allow communication from the client back to the server, thereby opening new market opportunities for the application.
The present invention enables the deployment of a client-server application on a multicast network in a way that permits multiple Clients to effectively receive the very same unicast transmission, i.e., simultaneously receive the same content from the same Server. This goal is achieved without reengineering the client-server application. Instead, software processes are introduced so that the distribution of the same unicast content transmission to additional Clients is completely transparent to the existing Client Processes at the Client side and server processes at the Server side. These new software emulation processes are placed on each of the Server and Client side of the network. In describing the invention, the Server side process is hereafter called Client Emulator Process and the Client side process is called Server Emulator Process. The Client and Server Emulator Processes completely hide the complexity of the multicast network to the Client Process at the Client and the Server Process at the Server. Moreover, the Client and Server Emulator Processes can be used to distribute additional specific information related to the communication session. Examples of this information are:
1. Encoding parameters of audio/video streaming transmissions that are sent to the Client Process prior to the audio/video stream, in order to allow the Client Process to load the necessary decoding technology. For example, Microsoft Windows Media technology requires that the receiving client has access to the a so called NSC file, which contains information such as the multicast IP address, port, stream format, and other station settings that Windows Media Player uses to connect to and play a multicast stream.
2. Announcements of specific sessions. This additional information is necessary in order to coordinate the Client Processes, taking full advantage of the multicasting capabilities. This mechanism is explained in detail below.
The preferred embodiment of the invention deals with client-server applications that use the unreliable transport UDP for delivering DATA messages. While this is the preferred solution for almost every client-server system currently on the market, there may be other systems which rely on TCP, which is more reliable than UDP, for the delivery of DATA messages. The system of the invention also can operate using much more reliable protocols As explained above, a reliable transport costs processing time and requires a back channel. The invention provides the possibility to easily adapt a system usually working in a bi-directional network, to work in unidirectional networks.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects and advantages of the present invention will become more apparent upon consideration of the following Specification and annexed drawings, in which:
FIG. 1 is a diagram illustrating data flow in a conventional unicast between a Server and a Client;
FIG. 2 is a diagram illustrating the sequence of data transmission between the Server and Client in the system of FIG. 1 ;
FIG. 3 is a diagram illustrating the data flow during communication between the Server and Client in the system of FIG. 1 ;
FIG. 4 is a diagram showing the general client-server topology in which the invention is used;
FIG. 5 . is a diagram illustrating operating principles of the invention;
FIG. 6 is a diagram illustrating the flow of signals between various components of the system of FIG. 4 ;
FIG. 7 is a diagram showing the communication between the Server and the Client;
FIG. 8 is a diagram of an alternative embodiment of the invention in which on the Client side one Server Emulator Process communicates with a plurality of Client Processes; and
FIG. 9 is a diagram of a configuration for broadcasting announcements.
DETAILED DESCRIPTION OF THE INVENTION
An example of a target topology in which the invention can be used is illustrated in FIG. 4 . As shown, a Server 100 is engaged in a communication session with three distinct Client hosts 120 each of which executes its respective own Client Process 230 . There can be fewer or more Client hosts. The communication is carried out over a public or private network 130 capable of supporting the TCP/IP protocol suite. In particular, the network 130 supports IP multicasting. Any conventional network capable of supporting IP multicasting can be used.
In FIG. 4 if the Client Process 230 of each of the plurality (three shown) of Client Hosts 120 would simultaneously establish a private unicast communication session with the Server Process 220 executed by the Server 100 , the total amount of bandwidth B required to deliver the same content to all three Client Processes 230 (measured on the link 102 ) would amount to three times the bandwidth b allocated to a session with a single Client Process 230 . In general, if N Client Processes would simultaneously request the same content from the same Server Process in a unicast protocol, the total amount of bandwidth B required to deliver the content to all of the Client Processes would be:
B=N*b (1)
where b is the amount of bandwidth required to deliver the content to a single Client Process.
A similar analysis can be made for other resources of the single Server Process, such as the total size of allocated buffer and the total amount of CPU time, when sought to be accessed by multiple Client Processes.
Referring to FIG. 5 , according to the preferred embodiment of this invention, the Server 100 hosts a Client Emulator 300 that executes a Client Emulator Process 320 . Server 100 also executes a conventional Server Process 220 . A Server Process 20 is responsible to manage and distribute the requested data. This is well known in the literature on client/server systems. In accordance with the invention, every Client 120 hosts an associated Server Emulator 310 that executes a conventional Server Emulator Process 330 . The Client Emulator Process 320 associated with the Client Emulator 300 of the Server 100 and each Server Emulator Process 330 associated with the Server Emulator 310 of each Client 120 may reside on separate Emulator 300 and 310 , as illustrated in FIG. 5 . That is, as shown in FIG. 3 , to the Server 100 is added the necessary circuitry and software to form an emulator 320 of a Client with a process that emulates a Client, i.e., a Client Emulator Process 320 . Similarly, to each Client is added the necessary circuitry and software to form an emulator of the Server and a process that emulates the Server, i.e., a Server Emulator Process 330 .
FIG. 6 , going from top to bottom, illustrates the flow of messages exchanged among Server Process 220 , and Client Emulator Process 320 of the Server 100 and the Server Emulator Process 330 and Client Process 230 of each Client 120 . The responsibilities of the respective Client emulator process 320 (at the Server) and Server Emulator Process 330 (of each Client) are hereafter described.
The two Emulator Processes 320 and 330 act to “fool” the respective Client and Server processes 220 and 230 by behaving as a real peer process. That is, on the Server side, the Client Emulator Process 320 at the Server 100 talks to the Server Process 220 at the Server 100 so that the Server thinks that it is talking to a Client. Similarly, the Client Process 230 at each Client 120 talks to the Server Emulator Process 330 that it hosts as if it were talking to the Server. For this purpose, the Client Emulator Process 320 hosted by the Server 100 initiates a communication session with the Server Process 220 of the Server. Moreover, during the session, the Client Emulator Process 320 also regularly sends heart beat messages HB to the Server Process 220 .
On the Client side the Server Emulator Process 330 , accepts a request message REQ sent from the Client Process 230 to establish the communication session. The Server Emulator Process 330 on the Client side also sends the content to the Client Process 230 of the Client 120 as a sequence of DATA messages. As explained below, the DATA messages sent by the Server Emulator Process 330 to the Client Process 230 on the Client side are received from Client Emulator Process 320 on the Server side. The Server Process 220 at the Server also expects and accepts the heart beat messages HB, according to the client-server protocol described above.
On the Server side, the Client Emulator Process 320 acts to encapsulate each IP unicast data message DATA received from the Server Process 220 in an IP multicast datagram. The encapsulation is accomplished by replacing the IP unicast destination data in the datagram header with the IP multicast destination data pre-configured in the client emulator process. The encapsulated data, called MDATA, is sent over the Network 130 to the respective Server Emulator Process 330 at each of one or more clients. On the Client side, each Server Emulator Process 330 , upon reception of an encapsulated data message MDATA, extracts the original data message DATA, packages it as an IP unicast message, and sends it to the associated Client Process 230 of the respective Client 120 .
The above effectively results in the original client-server configuration being split into two client-server subsystems linked by a multicast connection. As seen, due to the unidirectional nature of the IP multicast link between the Server side Client Emulator Process 320 and the Client side Server Emulator Process 330 , the Client Process 230 at the Client does not communicate directly with the Server Process 220 at the Server as in the original configuration described in FIGS. 1-3 . Instead, in the preferred embodiment of the invention, the flow of messages is initiated by the Client Emulator Process 320 on the Server side by sending a request message REQ to the Server Process 220 specifying the desired content (see also FIG. 5 ). In operation, either the client emulator process is operated manually by a launch command introduced from the end user or automatically by a time driven program like a broadcast guide interpreter that starts the session when the indicated time arrives. The Server Process 220 at the Server accepts the request, establishes a communication session and sends the content as a sequence of DATA messages to the Client Emulator Process 320 at the Server. The Client Emulator Process 320 maintains the session alive by regularly sending back heart beat messages HB to the Server Process 220 at the Server.
As shown in FIG. 7 , upon the Client Emulator 300 on the Server side receiving a DATA message from the Server Process 220 of the Server 100 , the Client Emulator Process 320 extracts the UDP Body section 420 from the UDP datagram, as illustrated, by stripping off the IP header 1 in 400 and the UDP header 1 in 410 . This is accomplished by suitable software. The Client Emulator Process 320 of the Client Emulator on the Server side then forwards on the Network 130 a new message MDATA in the form of a UDP/IP multicast datagram with the original UDP Body Section 420 . The IP address and destination port of the multicast datagram are known by the Client Emulator Process 320 on the Server side and by Server Emulator Process 330 on the Client side (described below). Even if it depends on the specific application protocol, it is in general important that the Client Emulator Process 320 forwards the data without delay or with minimal delay. In fact, in case of audio/streaming protocols, unexpected delays between subsequent datagrams can reduce the quality of the end-user experience by increasing the latency and causing a phenomenon known as jitter.
In the operation of the system shown in FIGS. 6 and 7 , on the Client side, the Client Process 230 sends a request message REQ to its hosted Server Emulator Process 330 requesting the desired content. Depending on the time of the request, the following situations may occur:
1) The Client side Server Emulator Process 330 receives the REQ message before the first MDATA message has arrived from the Client Emulator Process 320 on the Server side. In this case the Server Emulator Process 330 at a Client can either join the IP multicast session waiting for the arrival of MDATA message or simply reject the request.
2) The Client side Server Emulator Process 330 receives the REQ message while MDATA messages from the Server are “on air”. The Server Emulator Process 330 joins the IP multicast session and detects MDATA messages. Therefore it accepts the request message REQ from its associated Client Process 230 , establishes the session with the Client Process 230 and starts creating and sending DATA messages to the Client Process 230 at the Client 120 . DATA messages are UDP/IP unicast datagrams that carry the original UDP Body 420 . The IP Header 450 and the UDP Header 460 are configured according to the Client Process 230 request. Different solutions can be used to affect the configuration. For example, (1) there can be used a configuration file shared by both processes (server emulator process and client process); (2) the data is sent with the broadcast guide information. This data is shared by both processes as explained below. If both processes run on the same machine the server emulator process sends the data on the local host and next available port on the machine. The server emulator process communicates to the client the available port either through an API (if available by the client) or through a configuration file. (4) A configuration user interface can be implemented to introduce this data that will be shared by both processes.
3) The Server Emulator Process 330 on the Client side receives the REQ message after the last MDATA message has arrived from the Client Emulator Process 320 on the Server side. In this case the Client side Server Emulator Process 330 can only reject the request.
Alternatively, the Server Emulator Process 330 on the Client side has knowledge of the transmission schedule. Such a schedule is typically managed by the service provider and distributed in advance to all receiving Clients 120 . Knowing the transmission schedule, the Server Emulator Process 330 can easily decide to accept or reject a REQ message from the Client Process 230 from any one of the Clients.
It should be understood that some client-server technologies are capable of generating a native IP multicast stream but do require that the Client obtains from the Server an announcement of the multicast session. This could be sent with broadest gide information. An example of such a technology is Microsoft Windows Media technology. In this technology, the Client typically achieves this goal by retrieving a file from the Server containing the necessary information to join the multicast session and to correctly receive the content. In the system of the present invention, this retrieval of the file on the server does not take place. Instead, the file has to be sent in advance to the client using, for example, broadcast guide information distribution. In this scenario, the Client Emulator Process on the Server side does not need to package the content in a new multicast stream (MDATA). Instead, the role of the Client Emulator Process is merely to distribute to the Server Emulator Process 330 at each Client the multicast session announcement and to route the original stream onto the multicast network. In a similar way, the Server Emulator 310 at the Client does not need to repackage the received content (MDATA) in a unicast stream. It only needs to route it to the destination Client Process 230 . Even if the importance of the Client Emulator Processes is reduced, their contribution is still relevant, as they allow the deployment of a multicast capable client-server application on a pure unidirectional network.
In the embodiment of FIGS. 6 and 7 , only one Client Process 230 is shown communicating at a given time with a specific Server Emulator Process 330 at one or more Clients 120 . In a further embodiment illustrated in FIG. 8 , it is possible to allow multiple Client Processes 230 to simultaneously communicate with the same Server Emulator Process 330 . This configuration is useful when the Client Processes associated with a plurality of Clients 120 have access to one Server Emulator Process 330 through a local area network, and the one Server Emulator Process is deployed on a dedicated device. In this configuration, a single Server Emulator Process 330 serves as a common gateway between the Client Processes at the multiple Clients and the multicast network.
Referring to FIG. 8 , there is the Server 100 that hosts a Client Emulator 300 that has a Client Emulator Process 320 . The output of the Client Emulator 300 is shown as being to a plurality of Server Emulators 310 - 1 . . . 310 -N on the Client side. The Client side can be of the local network type. For example, each Server Emulator 310 services a plurality of Clients 120 . Each Server Emulator 310 executes a respective Server Emulator Process 330 to in turn communicate with a plurality of Clients 120 . For example, Server Emulator 310 -I communicates with Clients 120 - 1 _ through 1 K. The Server Emulator 310 -N is illustratively shown as communicating with Clients N 1 through NM.
One of the benefits of the embodiment of FIG. 8 is that the amount of resources required by one Server to support multiple Clients is no longer a linear function of the number N of Clients 120 . Instead, the amount of resources required to distribute content to multiple Clients 120 remains constant from the server 100 , regardless on how many Clients are interested in receiving the content. In particular, the amount of bandwidth B allocated to the entire service for all of the Clients 120 measured on the link 102 , is equivalent to the amount of bandwidth b required to serve a single client.
B˜b (2)
The benefit of the multicast transmission is that the data is sent once to a multicast address and each of the server emulators connects and listens at this address.
In concrete terms, this means that the cost of adding a Client 120 to the system is basically limited to the initial infrastructure investment of the Server and the number of Client stations. Moreover, the quality of the service provided does not degrade as new clients are added to the system.
As mentioned above, a key mechanism of the invention is the ability for a service provider to distribute information about single transmissions, called here an “announcement”, to the various Client receiving systems. A set of announcements is, for example, a broadcast guide and it defines a transmission schedule, such as of programs, over a given time period. Announcements play a fundamental role as they enable a Server Emulator Process 330 at a Client to receive the multicast data stream and pass it to the associated Client Process 230 . FIG. 9 illustrates how announcements are generated, distributed and used in a preferred embodiment.
In FIG. 9 , the announcement is a file or part of a file that contains in digital form at least the following components: an address or header; at least a unique content identifier; a descriptive title for the content to be transmitted; the date and time of the transmission; the type of application protocol used; and the IP multicast and port to which the content will be sent. Instead of specifying the type of application protocol used, the announcement can indicate the type of content by its MIME type (Multipurpose Internet Mail Extension). As is known and documented in the literature, MIME is used by browsers to link the appropriate plug-ins or helper applications to consume the data. MIME is a specification for formatting non-ASCII messages so that they can be sent over the Internet. An E-mail Client that supports MIME enables them to send and receive graphics, audio and video files via the Internet mail system.
The announcement can also include additional information as, for example, a more extensive description of the content, the duration of the transmission, and information on rating, price, producer and quality. Examples of such an announcement format are the Session Description Protocol SDP, known from the Mbone initiative (which is short for Multicast Backbone on the Internet) Mbone is an extension to the Internet to support IP multicasting—two-way transmission of data between multiple sites, or Microsoft Windows Media Announcement File (as described in the on-line Microsoft Library).
In FIG. 9 , the Service Provider 502 , considered to be an entity directed by human intervention, typically interacts with a Broadcast Guide Server Process 500 to define and produce the broadcast guide. The Process 500 is a software application program. While the Broadcast Guide Server Process 500 is preferably hosted on a Server 100 , previously described, it can also be hosted on a separate server. In a preferred embodiment, the user interface offered by the Broadcast Guide Server Process 500 allows the Service Provider 502 to graphically define and directly manipulate the broadcast guide and its announcements. A system and method for accomplishing this is described in U.S. patent application Ser. No. 09/738,390, filed Dec. 15, 2000, entitled “Decision Support System and Method for Planning Broadcast Transmissions, which is assigned to the Assignee of this application and whose disclosure is incorporated herein by reference in its entirety. Alternatively, the user interface can also be as simple as a command line application or a text editor. Moreover, although the Service Provider 502 typically interacts locally with the Broadcast Guide Server Process 500 , he or she can also interact with this process from a remote station, provided that an appropriate communication connection is available.
The broadcast guide 500 defined by the Service Provider 502 is temporarily stored in a local Data Store 508 , which can be any suitable storage media, such as a hard disk. This ensures that the broadcast guide data is stored for use in the event of a failure of the Broadcast Guide Server Process 500 . As soon as an announcement is defined, the Broadcast Guide Server Process 500 sends it to a Broadcast Guide Client Process 510 over a link 506 . This corresponds to the Client Process 230 previously defined with respect to FIGS. 4-8 . In a preferred embodiment, this transmission occurs periodically over the multicast type Network previously described. The periodic retransmission of the same announcement increases the probability that the announcement is effectively received by the Broadcast Guide Client Process 510 . Alternatively, the announcement can be sent once using any other reliable transport mechanism such as e-mail or FTP. Upon reception, the announcement is stored on the Client side in a local Data Store 518 to the Broadcast Guide Client Process 518 .
The User 512 at the Client side can view the broadcast guide through the Broadcast Guide Client Process 510 , which preferably offers a graphical user interface. As an alternative, the User 512 can view a locally stored textual report listing all announcements.
At the time at which the transmission is supposed to start, the Broadcast Guide Server Process 500 signals a request to send the content to a Client Emulator Process 320 at the Server side by passing relevant announcement parameters such as the unique content identifier and the IP multicast address and port on which the content is to be sent. As a consequence, the Client Emulator Process 320 operating with a Server Process 220 initiates the message exchange described in FIG. 6 . The Broadcast Guide Server Process 500 action is preferably triggered by a process internal timer, which is part of the application program. In absence of an automatic mechanism, the action can be manually triggered by the Service Provider 502 .
Similarly, as the transmission time approaches, the Broadcast Guide Client Process 510 on the Client side signals the request to receive the transmission to the Server Emulator Process 330 passing to the Broadcast Guide Client Process 510 relevant announcement parameters such as the unique content identifier and the IP multicast address and port on which the content can be expected. In a preferred embodiment, immediately after having signaled the Server Emulator Process 330 of the Client, the Broadcast Guide Client Process 510 also signals the Client Process 230 at the Client by passing the unique content identifier. This second action is only possible if the Client Process 230 offers a programmatic interface that can be used to direct the Client Process from an external software process. In absence of such a process, the User 512 has to manually signal the Client Process 230 , for example by starting the application and manually issue those commands necessary to initiate the content request. If there is no user interface then the user has to launch the client application manually introducing the appropriate commands to request the content by the server emulator process. Those commands can be different from a client to the other.
The actions of the Broadcast Guide Client Process 510 are preferably initiated by the User 512 at the Client, who thereby indicates an interest in receiving the content. Alternatively, the actions can also be initiated at a Client by a timer internal to the Broadcast Guide Client Process 510 itself. An automatic mechanism is particularly useful when the Client Process 230 is not involved in a viewing application but an unattended background process. this occurs, for example, when the client only stores the data but it does not display it. If a timer is used to initiate the action, a clock of the Server Emulator Process 330 at the Client has to be synchronized with a clock at the Client Emulator Process 320 at the Server. This synchronization ensures that the Client is ready to receive the content from the Server when this is effectively sent. It should be noted that, as described above, the Client user 512 can decide to view the content at any time that the content is “on air”, i.e., before the last MDATA message has arrived.
The client emulator process 320 sends the data to the multicast address to which the server emulator process 220 listens. This multicast address can be pre-configured for the entire system or can be sent with the broadcast guide information sent on a pre-configured multicast address. The other parts do not interact with each other. The server process interacts only with the client emulator process and the client process interacts only with the server emulator process as described above with respect to FIG. 5 .
Specific features of the invention are shown in one or more of the drawings for convenience only, as each feature may be combined with other features in accordance with the invention. Alternative embodiments will be recognized by those skilled in the art and are intended to be included within the scope of the claims.
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A system and method for broadcasting multicast transmissions of data content over a unidirectional network between a single server that executes a server process application and a plurality of clients, each of which executes a client process application. On the server side, the server includes a client emulator that executes a client emulator process application to convert unicast form data to multicast form data and on the client side each client operates in response to an emulator that executes a server emulator process application. Transmission of the data content takes place between the client emulator process on the server side and the server emulator process on the client side. Each client also includes and operates a client process application that receives data content from the server emulator process on the client side. On the client side, each client can have its own server emulator process or there can be a common server emulator process used by the client process application of all of the clients or groups of clients using a dedicated server emulator process for each group. The invention achieves multicast broadcast over a unicast network replacing the need for bi-directional networks and eliminates the need for a back channel and the need to send multiple copies of the data, thereby reducing the need for bandwidth and solving the problem of scalability of existing systems to broadcast multicast.
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TECHNICAL FIELD OF THE INVENTION
The present invention refers to the general field of the technology of the DNA recombinant proteins, for the production of a recombinant hybrid protein (p24/p17) derived from human immunodeficiency virus (HIV-1) to be used in diagnosis of acquired immunodeficiency disease virus (AIDS), vaccination, antibody production or in research.
BACKGROUND TO THE INVENTION
The epidemic provoked by the human immunodeficiency virus(HIV), today global, continues without bamers, and has as a consequence the syndrome of the acquired immunodeficiency(AlDS), recognized 12 years ago. The studies of the World Organization of Health estimated that more than 18 million people are infected and by the year 2000, 40 to 100 million people worldwide would have been infected by HIV-1 or HIV-2, from which 10 million will be children.
The hope for an effective therapy and, mainly, the prevention resides in the acquisition of new information on the virus, the mechanisms of the pathogenesis and in the search of experimental models (COOPER. Immunol. 4: 461, 1992). The current knowledge is that blocking the dissemination will be very important and therefore the early detection is needed for the treatment with the new drugs.
The virus concentration can greatly influenced the virus transmission in a body fluid. In the beginning of the epidemic the major routes of AIDS transmission were sexual contact and through transfusion with contaminated blood (Levis in: HIV and pathogenesis of AIDS p.26,1989). The syndrome was initially described in homosexual and bisexual men and in intravenous drug users (Mansur et al.,N. Engl. J. Med.305:1431,1989, but its occurrence from heterosexual activity were soon recognized (Harris, C et al.,N.Engl. J. Med.308:1181,1983). Today the principal means of transmission are the sexual, maternal-child, drug users and still blood in undeveloped countries. All of them can be explained to a great extent by the relative concentration of HIV in various body fluids.
HIV entry in the body and developed acute infection as observed by other virus. The HIV pathogenesis reflects several properties of the virus and the host immune response. AIDS final outcome is the differential expression of those major components of HIV infection
The first step of HIV infection is the interaction between the major lymphocyte receptor CD4 molecule, a member of immunoglobulin superfamily with the envelope gp120 protein. According to some reports described gp 120 is displaced, leading to the uncovering of domain on the envelope gp41 needed for virus cell fusion. Once in the cytoplasm several intracellular events take place ending with integration of a proviral form into cellular genome.
Besides entering cells via the direct interaction of the virus envelope with cell surface receptors, HIV can infect cells by other mechanisms. For example, during the course of studies on the humoral response to HIV-1 (infection, the phenomenon of antibody dependent enhancement (ADE), of HIV infection was found to occur (Homsy, J. et al. Science 244: 1357, 1989; Homsy, J. et al. Lancet i: 1285, 1988). The transfer of the virus into a cell through the complement or Fc receptor involves the binding of the Fab portion of nonneutralizing antibodies to the virus surface (Levy in: HIV and the pathogenesis.p.53,1994)
Clinical manifestations of acute HIV infection were recognized in the very early studies, and have been described in various articles (Thindall and Cooper, AIDS:5:1, 1991; NIV, MT et al. J. Infect. Dis. 168:1490, 1993). A newly infected host present within 1 to 3 weeks symptoms as headache, pain, muscle aches, sore throat, fever, swollen lymph nodes, a non pruritic macular erythematous rash involving the trunk and later the extremities.
It is estimated that 50 to 70% of patients primary infected with HIV will developed a syndrome of acute mononucleosis-like illness. This period is associated with high viremia levels, and the immune humoral response against the virus is detected between one week and three months (DAAR et al. New Engl. J. Med 324: 961,1991).
This specific immunity that initiates in this period is associated to a dramatic decline of the viremia, but the level of this immunity inadequate to suppress the viral multiplication. The expression of the virus persists in the lymph nodes, even when the presence of the virus in the plasma is difficult to be detected, and the mRNA is not detectable in the mononuclear cells of blood stream (MICHAEL et al. J. Virol. 66: 310-316, 1992).
HIV is classified, based on its morphology, genomic organization and pathogenic properties, as a member of the sub-family lentivirus of the family Retrovindae.
HIV-1 and HIV-2 as a lentivirus have the characteristic cone-shaped core composed of the viral p24 GAG protein. Inside this capsid are two identical RNA strands with the reverse transcriptase (RNA dependent DNA polymerase) and the nucleocapsid proteins (p9, p6) are closely associated. The inner portion of the viral membrane is surrounded by a myristylated p17 core protein (GAG) that provides the matrix (MA) for the viral structure which is important for virion integrity (McCune, J. M. et al. Cell 53: 55, 1988; Shulz, T. F. et al. AIDS Res. Human Retrov 8:1584, 1992). The virus surface is made by envelope glycoproteins derived from a precursors of Mw 160.000 which is inserted inside the cell into a gp120 and a gp41 transmembrane protein (TM). The central region of TM protein binds to the external viral gp120 in a non covalent ligation at two hydrophobic regions in the amino and carboxi termini of gp120 (Helseth, E. et al. J.Virol. 65:2119-2123, 1991.
Two other genes tat and rev are positive regulators for the replication of HIV, besides other proteins with accessory function, as the vpu, vif, vpr and nef (ROSEN, TIG 7: 9-14. 1991.).
One of the most notable properties of the genoma of the HIV-1 is its genetic variation (DESAI et al Proc. Natl. Acad. Sci. 83: 8380, 1986). The diversity can be important for many aspects of the biology of the virus, among them the tissue and cell specificity, clinical-pathological picture of the disease, geographical and temporary virus distribution, difference in the susceptibility of immune response, virulence and, especially, development of a vaccine of wide crossed reactivity. The mistake range esteemed for the variation of HIV is of a substitution in 10 4 synthesized nucleotides. Besides the substitution, deletions and inserts, whose frequency is more difficult of being evaluated can happen.
The gene env shows, along its structure, variable (V) and constant (C) regions. The principal neutralizing domain of the HIV-1 is placed in the third variable region (it raises V3) of the envelop glycoprotein (gp120). The loop V3 is an important neutralization epitop for, viral tropism and syncytium formation. In the V3 loop is the neutralyzing epitop for type-specific antibodies.
The laboratory diagnosis of any infectious agent is an important aspect for the control of infectious diseases. The precise diagnosis wins importance in the blood derivatives, whose use depends on the capacity of the tests in the detection of infectious agents' or its antigens. During the last decade, the technological progresses developed precise tests for the diagnosis of AIDS. Most of the researches concentrated efforts for the development of tests to be used in development countries were are the economic limitation. In those countries the HIV detection is not a routine.
The HIV-1 diagnosis is made with the indirect detection of the presence of the virus, indicated by the patient's immune response, evidenced by the presence of specific antibodies against the HIV-1 or the detection of the virus or its components.
The direct methods identify the virus multiplication in culture, detection of virus or antigens in immunoassays (ELISA), molecular hybridization or amplification of nucleic acids (PCR). However, some of these tests demand qualified personnel and equipped laboratories, what hinders its widespread use. An exception is the test of ELISA for the antigen p24, that can be detected in patients before the detection of antibodies, even so, in some cases, it is only detected in late infections and in some patient were it seems to be transient. Thus, the negative result of tests for HIV-1 antigens is not informative and it doesn't necessarily reflect a not infected individual (BYLUND et al. Clin. Lab. Med. 12: 305, 1992)
THE indirect methods determine the detection of antibodies. However, these antibodies are detected a time after infection from six weeks to six months.
Other indirect tests are those that not measure specific immune response but some proteins as β-2-microglobulina and neopterine, that indicate the activation of the immune response.
The detection of HIV-1 antibodies is the most used and efficient method to demonstrate the patient's contact with the virus or to verify the contamination of blood samples. In 1988, laboratories linked to the program Performance Evaluation Program of the Center of Control of Diseases (CDC, Atlanta, USA), evaluated around 32 million tests using antibody anti-HIV. A test of antibody anti-HIV is considered positive, when a sequence of tests, beginning with repeated ELISA and including additional, more more specific test, as the Western blot, they are consistently positive (CDC, MMWR ,1987). (BYLUND et al. Clin. Lab. Med. 12: 305, 1992).
The ELISA test is most used for detection of the HIV-1 because of the low cost, easy standardization and execution, Initially, it was licensed, in 1985, to test blood donors and blood products, being their use expanded to determine antibodies anti-HIV-1 in populations (Weiss et al. JAMA 253: 221, 1985). Several studies described the high sensibility of this test from 93% to 100% (BYLUND et al. Clin. Lab. Med. 12: 305, 1992).). Several kits of ELISA were licensed by the “Food and Drug Administration ” (FDA), in United States. Most of the tests used inactivated and purified lysates of T cell lineage, H-9, as source of antigen, that is rich in p24 and p17 antigens, with some loss of gp160, gp120 and p41 during the preparation. The contamination of the preparations of antigens with cell debris can originate the false positive result, due to cross reactions. These problems were now resolved with the use of recombinant antigens or synthetic peptides in the tests of ELISA, that constitute the last generation of tests to detect the antibody anti-HIV.
The recombinant proteins produced in bacterias and yeasts has been used as antigen for different types of tests, like ELISA, radioimmunoprecipitation, latex agglutination and Western blot. The sensibility and the specificity of these methods are excellent (99 to 100%), and they can detect the serum conversion earlier than ELISA that uses antigens of total virus.
The Western blot is the most used complementary test for the detection of specific antibody anti-HIV-1. In comparison to ELISA the Western blot is of higher cost and it requests technical personnel specialized due to subjective interpretation, because a universal approach doesn't exist for the interpretation of positive cases.
The bands of gp120 and gp4l don't have a good resolution, because these are glycosilated proteins of the envelope that migrates slowly in the gel, being considered an only band, for the interpretation of the results. A negative test is doesn't present any band, however the presence of an only band doesn't fill the requirements for a positive test and it is considered uncertain. This approach perhaps is not ideal to be used patients of high risk, or for patients with suggestive symptoms of HIV infection, especially if the band of p24 is detected (KLEINMAN. Arch. Pathol. Lab. Med., v.114, p.298, 1990.).
The false positive reactions can be observed in the ELISA test in the early and late phases of the patient's infection by HIV-1. False-positive results were described in patients with hiperbilirubinemie, disorders of the connective tissue, polyclonal gamopatias, besides in healthy individuals, as a result of a not very understood cross-reaction. However, it was verified that, in a population of low risk, the index of false-positive reactions of the tests of ELISA and Western blot combined was smaller than 10 −5 (BURKE et al., New Engl. J. Med. 319: 961. 1988).
Thus, there is need of a system with high sensibility for the detection of the virus, its components or antibodies from infected individuals' An important fact is it that the synthetic peptides and recombinant proteins are superior to the antigens from cell lysates. Thus, through the genetic engineering, it is possible to construct hybrid proteins that combine antigenic characteristic of more than one viral component.
It is object of the present invention to describe the recombinant hybrid p24/p17 protein of HIV-1, their corresponding encoding recombinant DNA molecule and the process of production of the recombinant hybrid p24/p17 protein of HIV-1 produced through techniques of genetic engineering, to be used for diagnosis, vaccination or in research.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other objects, features and many attendant advantages of the invention will be better understood upon a reading of the following detailed description when considered in connection with the accompanying drawings wherein:
FIG. 1 shows the vector pDS56 used for the expression of the recombinant hybrid p24/p17 protein of HIV-1
FIG. 2 shows the amino acid sequence of the recombinant hybrid p24/p17 protein of HIV-1
FIG. 3 shows the hydrofilicity profile from the recombinant hybrid p24/p17 protein of HIV-1
FIG. 4 shows a PAGE with the purified recombinant hybrid p24/p17 protein of HIV-1
DETAILED DESCRIPTION OF THE INVENTION
The methodology used for the production of the recombinant hybrid p24/p17 protein of HIV-1consists of the cloning and expression, in microorganisms, of the DNA corresponding to the gene that codes recombinant hybrid p24/p17 protein of HIV-1 using the methodology of the genetic engineering.
In order to better understand this invention the following examples, for illustrative purposes only, are described. The examples illustrate the present invention and are not intended to limit it in spirit or scope. The process can be understood better through the following description in consonance with the examples.
EXAMPLE 1
Amplification of the DNA (1)
The amplification of the DNA (1) derived from the proviral DNA, or starting from the vector that contains the cloned DNA of the gene for P-24/p17 hybrid protein was developed using specific oligonucleotides 5′ GGATCCCCGCTGACATGGAGCAAGGCG3 (SEQ ID NO. 1) and 5′ CGCGAAGCTTCAGGCTCCATCTGTC3′ (SEQ ID NO. 2). Those oligonucleotides were drawn to amplify, through polymerase chain reaction (PCR), the DNA region that encodes the corresponding fragment of the P-24/p17 hybrid protein. The primers also contains the sites for the restriction enzymes BamH-1 and Hind III.
The PCR reaction was performed by using Taq polymerase buffer (50 mM KCI, 100 mM Tris-HCI pH 9.0-9.5, 1.5-2.5 mM MgCI 2 and 1-2% triton X-100), 0.1-1 U of Taq polymerase (Promega ,E.U.A., Cat. no. M186A), 0.5-1.5 mM MgCI 2 , 20-50 mM of each nucleotide (dATP,dCTP,dGTP,dTTP) 10-30 umoles of each primer, and 0.01 a 0.1 μg cDNA and H 2 O q.s.p. 50-100 μI. The reaction was performed in 1-2 cycles at 94-96° C./1-2 min; 53 to 55° C. 1-2 min.; 70-72° C./1-2 min; 30 cycles at 94-96° C./1 to 2min; 36-38° C./1-2min; 70-72° C./1-2 min and more 1 cycle to 94-96° C./1-2 min; 36-38° C./1 to 2 min; 70-72° C./10-15 min.
The PCR product was fractionated by electrophoresis in 1.5-2.0% agarose gel before purification of amplified fragment band was cutted out the gel. The fragment was purified by adding 2-3 times v/v of Nal solution (Nal 8M+0.022 M DTT) and sodium phosphate buffer (1M pH 6.0-6.5) and incubated for 5-10 min. at 50-56° C. Glass beads were added to the suspension, mixed , incubated 1-5 min at room temperature and centrifuged 10-30 seconds . The pellet were washed with ethanol buffer(75% of ethanol, 0.01 M Tris-HCI, pH 7.0-7.6, 0.01 M EDTA, pH 8.0-8.5). The DNA was eluted from the glass spheres with buffer (Tris pH 7.0-7.4 10 mM, 1-3 mM EDTA) at 50-56° C. for 1-5 min.
EXAMPLE 2
Cloning (2)
The PCR product was digested with enzyme Hind III with 10-20 U of Hind III (Biolabs, England) plus 3-5 I buffer (Promega, EUA) in 30-50 μl volume of H 2 O. The reactions were incubated at 37° C. for 2-4 h. After this time 10-20 U of Bam HI (Biolabs, England) plus 5-10 μI of react III buffer (BRL, USA) were added to a final 50-100 μI volume of H 2 O dd and it was incubated at 37° C. for 2-4 h. For cloning of the PCR product into plasmid PDS-56 (FIG. 1 ), the vector was digested with 10-20 U of enzyme Hind III(Promega, USA), 2-5 μI buffer I B (Promega,E.U.A.) in 20-50 μI final volume of H 2 O , and incubation at 37° C. for 2-4 h. To the reaction was added 10-20 U of the enzyme Bam Hi (Promega, USA), 5-10 μI of react III (BRL, E.U.A), in 50-100 μfinal volume of H 2 O , and incubation at 37° C. for 2-4 h. After digestion the DNA was fractionated by electrophoresis in a 1-2% TAE-agarose gel and bands purified as already described.
The ligation reaction was performed by adding 20-50 ng of the DNA fragment insert, 5-15 ng of the vector DNA, plus 0.5-2.0 U of T4 ligase (Promega, USA), 5mM ATP (Promega,E.U.A.), ligation buffer(Promega,E.U.A.), H 2 O dd qsp 15 μI, with incubation at 14-16° C. (BOD, FANEN, Brazil) for 12-18 h.
EXAMPLE 3
Transformation (3)
The bacterial transformation was done with Escherichia coli by adding the ligation reaction completed to 40-60 μl volume buffer (Tris 10 mM pH 7.2-7.4, EDTA 1 mM) to 100 μl of competent bacteria suspension. The tubes were slightly rotated and immediately incubated on ice bath for 20-40 min. After that, they were submitted to a thermal shock at 40-42° C. for 1-3 min. and kept on ice bath for further 20-40 seconds. LB medium (Bacto triptona 1% p/v, extract of yeast 0.5% p/v, NaCl 171 mM) without antibiotic was added at double volume and incubated at 37° C. for 1-2h. The bacteria were pelleted, homogenized in LB and inoculated in Petri dish plates with LB agar (agar 1.5% p/v, yeast extract 0.5% p/v, triptone 0.1% p/v, NaCl 0.5% p/v pH 7.2-7.5) with 50-200 pg/ml ampicillin and 20-100 pg/ml kanamycin. The plates were incubated at 37° C. for 15-24 h. For the selection of the positive clones they were grown in LB with 50-200 pg/ml ampicillin and 20-100 pg/ml kanamycin at 37° C. under agitation for 15-20 h. After incubation a PCR using specific primers of the vector (for amplification of the area corresponding to insert) being the primer (sense) 5′-TTCATTAAAGAGGAGAAATT-3′(SEQ ID NO. 3) and primer (anti-sense) 5′-CTATCAACAGGAGTCCAAGC-3′(SEQ ID NO. 4). The reaction was made with Taq. polymerase buffer10X (KCl 500 mM, Tris-HCl 100 mM pH 9.0-9.5, MgCl 2 15-25 mM and triton X-100 1-2%), 0.5-1.0 U of Taq polymerase (Promega, USA), 0.5-1.5 mM MgCl 2 , 20-50 mM of each nucleotide (dATP, dCTP, dGTP, dTTP), 10-30 pmoles of each primer, 0.5-1 μl of bacterial suspension and H 2 Odd sterile qsp 20-40 μl.
The reaction was processed with 1-3 cycles of 94-96° C./5 min., 50-55° C./1-2 min., 70-72° C./1-2 min., 30 cycles of 94-96° C./30-45 seg., 45-50° C./30-45 seg., 70-72° C./30-45 seg. and 1 cycle of 94-96° C./1-2 min., 45-50° C./1-2 min., 70-72° C./10-15 min. The of this reaction was fractionated through 1-2%. agarose gel electrophoresis.
EXAMPLE 4
Sequencing (4)
The positive clones were sequenced to confirm the sequence of FIG. 2 and presents the hydrofilicity profile as showed in FIG. 3 .
EXAMPLE 5
Protein production (5)
The positive clones were used for production of protein and they were grown in LB medium with 50-200 μg/ml ampicillin, 50-200 of Kanamycin μg/ml and incubated at 37° C. under agitation until the optical density (OD 600 nm) of 0.5-0.7. Then, for the induction of the protein, IPTG(Isopropyl-□-D-thiogalactpyranoside) to 0.2-0.4 M was added and incubated for 3-5 h. The bacteria were centrifuged, the supernatant was discarded and the pellet homogenized in buffer A (guanidine-HCI 5-6 M, sodium phosphate 0.1-0.2 M, Tris 0.01-0.02 M pH 7.8-8.0) with agitation for 1-2 h. A polyacrylamide gel shows the expression in the bacteria. (FIG. 4)
EXAMPLE 6
Protein purification (6)
After the centrifugation the supernatant was applied to a column with Ni-NTA (nickel chelate) resin. For purification of the protein the column was washed sequentially with buffer A, buffer B (Urea 7-8 M, phosphate of sodium 0,1-0,2 M, Tris 0.01-0.02 M pH 7.8-8.0) and with buffer C (Urea 7-8 M, phosphate of sodium 0.1-0.2 M, Tris 0.01-0.02 M pH 7.0-7.2). The protein was eluted with buffer D (Urea 7-8 M, sodium phosphate 0.1-0.2 M, Tris 0.01-0.02 M pH 5.0-5.2) and sequentially with urea 7-8 M, phosphate of sodium 0.1-0.2 M, Tris 0.01-0.02 M pH 40-4.2. Fractions were collected and 50 μI of each fraction was diluted v/v in sample buffer, heated for 10 min. and submitted to electrophoresis in polyacrylamide gel (SDS-PAGE).
While the present invention has been described in connection with examples, it will be understood that modifications and variations apparent to those ordinary skill in the art are within the scope of the present invention.
5
1
27
DNA
Human immunodeficiency virus
1
ggatccccgc tgacatggag caaggcg 27
2
25
DNA
Human immunodeficiency virus
2
cgcgaagctt caggctccat ctgtc 25
3
20
DNA
Artificial Sequence
Description of Artificial Sequence PCT, primer
of the vector
3
ttcattaaag aggagaaatt 20
4
20
DNA
Artificial Sequence
Description of Artificial Sequence PCT, primer
of the vector
4
ctatcaacag gagtccaagc 20
5
199
PRT
Human immunodeficiency virus
5
Glu Ala Leu Asp Lys Ile Glu Glu Glu Gln Asn Lys Ser Lys Lys Lys
1 5 10 15
Ala Gln Gln Ala Ala Ala Asp Thr Gly His Ser Ser Gln Val Ser Gln
20 25 30
Asn Tyr Pro Ile Val Gln Asn Ile Gln Gly Gln Met Val His Gln Ala
35 40 45
Ile Ser Pro Arg Thr Leu Asn Ala Trp Val Lys Val Val Glu Glu Lys
50 55 60
Ala Phe Ser Pro Glu Val Ile Pro Met Phe Ser Ala Leu Ser Glu Gly
65 70 75 80
Ala Thr Pro Gln Asp Leu Asn Thr Met Leu Asn Thr Val Gly Gly His
85 90 95
Gln Ala Ala Met Gln Met Leu Lys Glu Thr Ile Asn Glu Glu Ala Ala
100 105 110
Glu Trp Asp Arg Val His Pro Val His Ala Gly Pro Ile Ala Pro Gly
115 120 125
Gln Met Arg Glu Pro Arg Gly Ser Asp Ile Ala Gly Thr Thr Ser Thr
130 135 140
Leu Gln Glu Gln Ile Gly Trp Met Thr Asn Asn Pro Pro Ile Pro Val
145 150 155 160
Gly Glu Ile Tyr Lys Arg Trp Ile Ile Leu Gly Leu Asn Lys Ile Val
165 170 175
Arg Met Tyr Ser Pro Thr Ser Ile Leu Asp Ile Arg Gln Gly Pro Lys
180 185 190
Glu Pro Phe Arg Asp Tyr Val
195
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The present invention describes recombinant p24/p17 hybrid protein derived from the human immunodeficiency virus, their corresponding encoding recombinant DNA molecule and the process of production of the recombinant protein produced through genetic engineering techniques, to be used in diagnosis, vaccination or in research.
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CROSS REFERENCE TO RELATED APPLICATION
This application is a division of prior copending application Ser. No. 07/996,204 filed Dec. 23, 1992, the contents of which are incorporated herein by reference thereto.
FIELD OF THE INVENTION
The present invention is related to a method of separating a hydrogen-containing gas stream into a relatively hydrocarbon-free, hydrogen-rich stream and a relatively hydrogen-free, hydrocarbon stream.
BACKGROUND OF THE INVENTION
Various types of catalytic hydrocarbon conversion reaction systems have found widespread utilization throughout the petroleum and petrochemical industries for effecting the conversion of hydrocarbons to different products. Moreover, such systems often result in either the net production or the net consumption of hydrogen. As applied to petroleum refining, these reaction systems have been employed to effect numerous hydrocarbon conversion reactions, including catalytic reforming and catalytic dehydrogenation of paraffins.
Catalytic dehydrogenation of C 2 -C 5 hydrocarbons is well known in the petroleum industry. The monoolefinic hydrocarbon products derived therefrom are generally useful as intermediates in the production of other more valuable hydrocarbon conversion products.
Catalytic dehydrogenation can be combined with other catalytic hydrocarbon conversion processes to produce a variety of useful products. For example, the olefins produced during catalytic dehydrogenation of a liquid petroleum gas stream containing isobutane can be used in conjunction with an etherification unit wherein isobutylene is reacted with methanol to produce methyl-t-butyl ether (MTBE). Another example of combining catalytic dehydrogenation of hydrocarbons with other hydrocarbon conversion processes is the use of propylene and butylenes produced from dehydrogenation in an HF alkylation unit wherein these olefins are alkylated with isobutane to produce a high octane motor fuel.
The separation of a hydrogen-rich gas stream from the effluent of a catalytic hydrocarbon conversion process is well known in the art. It is important to separate the hydrogen-rich gas stream from the catalytic conversion effluent for several reasons:
(1) catalytic conversion reactions generally require the presence of hydrogen and recycling the processed-derived, hydrogen-rich gas stream to the catalytic conversion reaction zone is cost effective;
(2) any excess processed-derived, hydrogen-rich gas can be used in other catalytic hydrocarbon conversion processes located at the refinery; and
(3) it is particularly desirable not to lose product olefins or unreacted feed hydrocarbons in the product hydrogen.
An example of a process for separating a hydrogen-rich gas stream from a catalytic reforming effluent can be found in U.S. Pat. No. 3,520,799 (Forbes). This patent discloses a method of obtaining a high purity hydrogen gas stream from a catalytic reforming effluent by passing the effluent to a low pressure vapor-liquid equilibrium separation zone from which there is produced a hydrogen-containing gas stream and a liquid hydrocarbon stream. After compression, the hydrocarbon-containing gas stream is recontacted with the liquid hydrocarbon stream and the resulting mixture is passed to a high pressure vapor-liquid equilibrium separation zone. A second hydrogen-containing gas stream is produced having a higher hydrogen purity than the first. A portion of this second hydrogen-containing gas stream is passed into an absorption zone where it is contacted with a lean sponge oil, preferably comprising C 6 + hydrocarbons. A third hydrogen-containing gas stream is removed from the absorption zone and, after cooling, passed to a third vapor-liquid equilibrium separation zone. The sponge oil is removed from the absorption zone and is admixed with the liquid hydrocarbon stream from the low pressure vapor-liquid equilibrium separation zone prior to recontacting thereof with the compressed hydrogen-containing gas stream. A hydrogen-rich gas stream is removed from the third vapor-liquid equilibrium separation zone.
U.S. Pat. No. 3,882,014 (Monday et al.) also discloses a method of obtaining a high purity hydrogen gas stream from a catalytic reforming effluent. The effluent is first passed to a vapor-liquid equilibrium separation zone from which there is recovered a liquid hydrocarbon stream and a hydrogen-containing gas stream. After compression, the hydrogen-containing gas stream is passed to an absorption zone wherein it is contacted with a sponge oil comprising stabilized reformate. A hydrogen-rich gas stream is recovered from the absorption zone with one portion thereof being recycled to the reforming zone while the remainder is recovered for use in other hydrocarbon conversion processes.
U.S. Pat. No. 4,212,726 (Mayes) discloses another method of recovering hydrogen-rich gas streams from catalytic reforming reaction zone effluents wherein the reaction zone effluents from the catalytic reforming process are passed to a first vapor-liquid equilibrium separation zone from which is recovered a first hydrocarbon liquid stream and a first hydrogen-containing gas stream. After compression, the hydrogen-containing gas stream is passed to an absorption column where it is contacted with the first liquid hydrocarbon from the vapor-liquid equilibrium separation zone and stabilized reformate. A hydrogen-rich gas stream is recovered from the absorption zone with one portion being recycled back to the catalytic reforming reaction zone and the balance being recovered for use in other hydrocarbon conversion processes.
In all of the above patented processes, the catalytic hydrocarbon conversion effluent from which the hydrogen-rich gas stream is recovered is an effluent from a catalytic reforming reaction zone whereas in the present invention the catalytic hydrocarbon conversion effluent from which the hydrogen-rich gas stream is recovered is an effluent from a catalytic dehydrogenation reaction zone. There are significant differences in reactions, feedstocks, operating conditions and effluents between reforming and dehydrogenation processes.
Catalytic reforming reactions are numerous and varied. For example, the catalyst and operating conditions used in reforming promote the formation of higher octane unsaturated cyclic compounds such as aromatics by dehydrogenation of naphthenes, isomerization of paraffins and naphthenes, dehydrocyclization of paraffins, and hydrocracking. However, in a catalytic dehydrogenation zone, only one reaction is predominant, that reaction being dehydrogenation of paraffins to produce olefins.
Reforming feedstocks contain a mixture of hydrocarbon components that typically have a boiling point range of about 100° F. to about 400° F. In contrast, dehydrogenation feedstocks are typically made up of pure components of methane (b.p. -127.5° F.), propane (b.p. -43.7° F.), isobutane (b.p. 10.9° F.) and isopentane (b.p. 82.1° F.), each having much lower boiling points.
The effluent from a reforming reaction zone contains a significant amount of normally liquid hydrocarbons such as benzene, toluene and xylenes. Accordingly, a suitable separation of the hydrogen-rich gas stream from the catalytic hydrocarbon conversion effluent can generally be effected by condensing out the hydrocarbons and absorbing the hydrogen-containing gas with lean oil at relatively mild conditions of temperature and pressure. For instance, in the Forbes and Mayes patents, the absorber temperatures are about 90°-150° F. Further, in the Monday et al. patent, the absorber temperature is about 100° F.
In contrast, the dehydrogenation effluent contains a significant amount of lower molecular weight olefinic hydrocarbons that are normally in the gaseous state. Accordingly, the operating conditions, particularly the absorber temperature, must be substantially lower to accomplish effective separation of a hydrogen-rich gas stream from a dehydrogenation effluent.
U.S. Pat. No. 4,381,418 (Gewartowski et al.) discloses a process for recovering a hydrogen-rich gas stream from the effluent of a catalytic dehydrogenation reaction zone comprising compressing the dehydrogenation effluent stream and cooling by indirect heat exchange using catalytic dehydrogenation feedstock comprising a hydrogen/hydrocarbon admixture, forming a hydrogen-containing gas stream and a liquid hydrocarbon stream, separating the hydrogen-containing gas stream and the liquid hydrocarbon stream, cooling the hydrogen-rich gas stream by gas expansion to form a hydrogen-rich gas stream, combining one portion of the hydrogen-rich gas stream with a paraffinic hydrocarbon stream to form the catalytic dehydrogenation feedstock admixture referred to above and recovering the other portion of said hydrogen-rich gas stream. Nowhere in Gewartowski et al. is there disclosed or suggested contacting a hydrogen-containing gas stream with a liquid absorbent.
SUMMARY OF THE INVENTION
It has been discovered that integrating a cold temperature absorption zone into a dehydrogenation effluent separation process can effectively recover a relatively hydrocarbon-free, hydrogen-rich gas stream for recycle to the dehydrogenation reaction zone or for use in other hydrocarbon conversion reaction zones. The present invention will recover higher purity hydrogen and liquefiable hydrocarbons more economically than prior art processes. It is important that the hydrogen-rich stream recycled to the dehydrogenation reaction zone contain only a minimal amount of hydrocarbons for several reasons:
(1) in equilibrium reaction systems, such as is the case with the dehydrogenation of C 2 -C 5 hydrocarbons, higher conversion results from having a minimal amount of olefinic hydrocarbon product admixed with the feed;
(2) smaller and less expensive reactors can be employed if the recycle hydrogen is relatively hydrocarbon-free;
(3) there is a reduction in product losses in the net hydrogen stream as shown herein wherein the net hydrogen and recycle gas have the same origin and hence the same composition; and
(4) in the dehydrogenation zone, lower utilities are associated with the use of a charge heater and lower capital investment is associated with the combined feed heat exchanger.
As used herein, the terms hydrogen-rich and methane-rich are intended to represent relative hydrogen and methane concentrations in a particular stream in comparison to the hydrogen and methane concentration in other streams in the process of the present invention.
The present invention is a process for producing a hydrogen-rich gas stream by treating an effluent comprising hydrogen and at least about 20 to 60 mole % C 2 -C 5 olefinic hydrocarbons from a catalytic dehydrogenation conversion reaction zone comprising the steps of: cooling the dehydrogenation effluent by indirect heat exchange with a stream comprising at least a portion of the hydrogen-rich gas stream; passing the effluent to a first vapor-liquid separation zone and recovering therefrom a hydrogen-containing vapor phase and a liquid phase comprising C 2 -C 5 olefinic hydrocarbons; contacting the hydrogen-containing vapor phase with a lean liquid absorbent comprising C 2 -C 5 hydrocarbons in an absorption zone to produce the hydrogen-rich gas stream and a methane-rich liquid absorbent; refrigerating the hydrogen-rich gas stream and passing the refrigerated hydrogen-rich gas stream in indirect heat exchange with the hydrogen-containing vapor phase; and recovering the hydrogen-rich gas stream.
In one embodiment, the present invention is a process for producing a hydrogen/hydrocarbon admixture for use in a catalytic dehydrogenation reaction zone by treating an effluent of the dehydrogenation zone, the effluent comprising at least about 20 to 60 mole % C 2 -C 5 olefinic hydrocarbons, comprising the steps of: cooling the effluent by indirect heat exchange with the admixture; passing the effluent to a first vapor-liquid separation zone and recovering therefrom a hydrogen-containing vapor phase and a liquid phase comprising C 2 -C 5 olefinic hydrocarbons; contacting the hydrogen-containing vapor phase with a lean liquid absorbent comprising C 2 -C 5 hydrocarbons at a temperature of less than about -120° F. in a countercurrent absorption zone to produce a hydrogen-rich gas stream and a methane-rich liquid absorbent; refrigerating the hydrogen-rich gas stream to a temperature of less than about -250° F. and passing the refrigerated hydrogen-rich gas stream in indirect heat exchange with the hydrogen-containing vapor phase; admixing the hydrogen-rich gas stream with a hydrocarbon liquid comprising C 2 -C 5 paraffins to form the admixture; and recovering the admixture.
In another embodiment, the present invention is a process for the catalytic dehydrogenation of an admixture comprising hydrogen and at least about 20 to 60 mole % C 2 -C 5 paraffinic hydrocarbons comprising the steps of: contacting the admixture with a dehydrogenation catalyst in a dehydrogenation zone at dehydrogenation conditions to produce an effluent stream comprising hydrogen and at least about 20 to 60 mole % C 2 -C 5 olefinic hydrocarbons; cooling the effluent to a temperature of less than about -200° F. by indirect heat exchange with the admixture; passing the effluent to a first vapor-liquid separation zone and recovering therefrom a hydrogen-containing vapor phase and a liquid phase comprising at least about 20 to 60 mole % C 2 -C 5 olefinic hydrocarbons; passing the hydrogen-containing vapor phase into indirect heat exchange with a hydrogen-rich gas; contacting the hydrogen-containing vapor phase with a lean liquid absorbent comprising at least about 20 to 60 mole % C 2 -C 5 paraffinic hydrocarbons at a temperature of less than about -250° F. in a countercurrent liquid absorption zone to produce the hydrogen-rich gas stream and a methane-rich liquid absorbent; refrigerating the hydrogen-rich gas stream to a temperature of less than about -280° F. and passing the refrigerated hydrogen-rich gas stream in indirect heat exchange with the hydrogen-containing vapor phase; admixing the hydrogen-rich gas stream with a hydrocarbon liquid comprising 20 to 60 mole % C 2 -C 5 paraffinic hydrocarbons to form the admixture; and recycling at least a portion of the admixture to the dehydrogenation zone.
BRIEF DESCRIPTION OF THE DRAWING
The accompanying FIGURE is a schematic flow diagram of one embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The feedstock for the dehydrogenation reaction zone of the present invention is an admixture of hydrogen and C 2 -C 5 paraffinic hydrocarbons. Suitable C 2 -C 5 hydrocarbons include ethane, propane, butane and pentane, and any mixtures or isomers thereof. In a preferred embodiment, the feedstock comprises less than about 2 mole % C 6 + hydrocarbons. A suitable hydrogen to hydrocarbon mole ratio is about 0.1:1 to 40:1, preferably about 0.4 to 1.0.
The hydrocarbon feedstock of the present invention can be pretreated to remove impurities such as water, organic nitrogen, metals, and sulfur compounds that are harmful to the dehydrogenation catalyst. This pretreatment usually consists of directing the feed stream through at least one guard bed containing activated alumina.
The C 2 -C 5 paraffinic hydrocarbon feedstock is introduced into a dehydrogenation section having at least one reactor that converts these paraffins to olefins in the presence of a dehydrogenation catalyst.
Any suitable dehydrogenation catalyst may be used in the process of the present invention. Generally, the preferred catalyst comprises a platinum group metal component, an alkali metal component and a porous inorganic oxide material. The catalyst may also contain promoter metals which advantageously improve the performance of the catalyst. It is preferable that the porous carrier material of the dehydrogenation catalyst be an absorptive high surface area support having a surface area of about 25 to about 500 m 2 /g. The porous carrier material should be relatively refractory to the conditions utilized in the reaction zone and may be chosen from those carrier materials which have traditionally been utilized in dual function hydrocarbon conversion catalysts. A porous carrier material may therefore be chosen from activated carbon, coke, or charcoal, silica or silica gel, clays and silicates including those synthetically prepared and naturally occurring, which may or may not be acid-treated as, for example, attapulgus clay, diatomaceous earth, kieselguhr, bauxite; refractory inorganic oxide such as alumina, titanium dioxide, zirconium dioxide, magnesia, silica alumina, alumina boria, crystalline alumina silicates or a combination of one or more of these materials. The preferred porous carrier material is a refractory inorganic oxide, with the best results being obtained with an alumina carrier material, particularly gamma alumina. In a preferred embodiment, the catalyst is a spherically-shaped gamma alumina carrier having a diameter of about 1/16".
The preferred dehydrogenation catalyst also contains a platinum group metal component. Of the platinum group metals, which include palladium, rhodium, ruthenium, osmium and iridium, the use of platinum is preferred. The platinum group component may exist within the final catalyst composite as a compound such as an oxide, sulfide, halide, oxysulfide, etc., of an elemental metal, or in combination with one or more other ingredients of the catalyst. It is believed that the best results are obtained when substantially all of the platinum group components exist in the elemental state. The platinum group component generally comprises from about 0.1 to about 2 wt. % of the final composite, calculated on an elemental basis. It is preferred that the platinum content of the catalyst be between about 0.2 and 1 wt. %. The preferred platinum group component is platinum, with palladium being the next preferred metal.
The platinum group component may be incorporated into the catalyst composite in any suitable manner such as by coprecipitation or cogelation with the preferred carrier material, or by ion-exchange or impregnation of the carrier material. The preferred method of preparing the catalyst normally involves the utilization of a water-soluble decomposable compound of a platinum group metal to an impregnated carrier material. For example, the platinum group component may be added to the support by commingling the support with an aqueous solution of chloroplatinum or chloropalladic acid. An acid such as hydrogen chloride is generally added to the impregnation solution to aid in the distribution of the platinum group component throughout the carrier material.
Additionally, the preferred catalyst contains an alkali metal component chosen from cesium, rubidium, potassium, sodium and lithium. The preferred alkali metal is normally either potassium or lithium, depending on the feed hydrocarbon. The concentration of alkali metal may range from about 0.1 to 3.5 wt. %, but is preferably between 0.2 and about 2.5 wt. % calculated on an elemental basis. This component may be added to the catalyst by the methods described above as a separate step or simultaneously with the solution of another component.
As previously noted, the dehydrogenation catalyst may also contain promoter metal. One such preferred promoter is tin. The tin component should constitute about 0.01 to about 1 wt. % tin. It is preferred that the atomic ratio of tin to platinum be between 1:1 and 6:1. The tin component may be incorporated into the catalytic composite in any suitable manner known to effectively disperse this component in a very uniform manner throughout the carrier material. Thus, the component may be added to the carrier material by coprecipitation.
A preferred method of incorporating the tin component involves coprecipitation during the preparation of the preferred carrier material. This method typically involves the addition of a suitable soluble tin compound, such as stannous or stannic chloride to an alumina hydrosol, mixing these ingredients to obtain a uniform distribution throughout the sol and then combining the hydrosol with a suitable gelling agent and dropping the resultant admixture into an oil bath. The tin component may also be added through the utilization of a soluble decomposable compound of tin to impregnate the calcined porous carrier material. A more detailed description of the preparation of the carrier material and the addition of the platinum component to the carrier material may be obtained by reference to U.S. Pat. No. 3,745,112.
The dehydrogenation catalyst may be employed in the dehydrogenation reactor as a fixed bed, fluidized bed, or a moving bed. Moreover, the dehydrogenation catalytic reactor may contain multiple catalyst beds. In one such system, the catalyst is employed within an annular bed through which it is movable via gravity flow. In such a system, there are typically a plurality of reactors in series. It is common practice to remove the catalyst from the bottom of the last reactor, regenerate the catalyst, then return the catalyst to the top of the reactor.
The operating conditions employed in the dehydrogenation reactor will vary depending upon such factors as catalyst activity, feedstock and desired conversion. A general range of conditions which may be employed for dehydrogenation of a light hydrocarbon include a temperature of from about 1022° F. to about 1472° F., a pressure from about 0.01-10 atmospheres absolute, a liquid hourly space velocity between about 0.1-100 hr -1 and a hydrogen to hydrocarbon mole ratio from about 0.01:1 to about 40:1.
Upon removal of the dehydrogenation effluent from the last reactor in the dehydrogenation zone, it is cooled by indirect heat exchange typically with the hydrogen/hydrocarbon admixture that is used for feed to the dehydrogenation reactor. The dehydrogenation effluent is then further cooled usually with air or cooling water to a temperature of about 100° F. The dehydrogenation effluent is then compressed to 60-200 psig. That compressor effluent is then cooled usually with air or cooling water to about 100° F. and then directed to a contaminant removal zone to remove such components as HCl, H 2 S and water.
The dehydrogenation effluent exits the dehydrogenation section and enters a first means for indirect heat exchange with the dehydrogenation feed stream. The preferred first heat exchanger means is a plate-fin heat exchanger. A plate-fin heat exchanger is a tubeless vessel that contains a plurality of separate adjacent compartments for the flow of process fluids (usually in the opposite direction). Although the process of the present invention is described herein with respect to a particular process stream passing through the plate-fin heat exchanger and coming into indirect heat exchange with another process stream, the present invention is not intended to exclude the presence of other process streams simultaneously passing through the plate-fin heat exchanger and coming into indirect heat exchange therewith. Extending from the inner walls of these compartments is a plurality of fins that promote heat transfer from fluids flowing in adjacent compartments. Passing the dehydrogenation effluent into this first plate-fin heat exchanger lowers the temperature of the dehydrogenation effluent from about 100° F. entering the first plate-fin heat exchanger to about 10° to -150° F. exiting the first plate-fin heat exchanger.
Following the indirect heat exchange step, the dehydrogenation effluent is passed to a first vapor-liquid equilibrium separation zone, thereby producing a liquid phase comprising C 2 -C 5 olefinic hydrocarbons and a hydrogen-containing vapor phase. The first vapor-liquid equilibrium separation zone is maintained at a temperature of less than about 10° to -150° F. and a pressure of about 100 psig.
The liquid phase preferably comprises at least about 20-70 mole % of the olefinic hydrocarbons and unreacted paraffins contained in the reactor effluent. In a preferred embodiment, at least a portion of the liquid phase is passed to a second vapor-liquid equilibrium separation zone to produce a methane-rich overhead that may be rich in hydrogen and light hydrocarbons and a hydrocarbon liquid product stream of reduced vapor pressure. The second vapor-liquid equilibrium separation zone can be operated at a temperature of about 10° to -150° F. and pressure of about 5 psig. The overhead stream can be sent back to the dehydrogenation zone, in particular the suction end of the reactor effluent compressor. This enables the second vapor-liquid separator to be operated at a lower vapor pressure. Also recycling this overhead stream back to the dehydrogenation section reduces product losses.
The liquid hydrocarbon product stream comprises predominantly C 2 -C 5 olefinic hydrocarbons and unreacted paraffinic hydrocarbons. This liquid hydrocarbon product stream can be passed into a pump that increases the pressure of the liquid product stream to about 200-300 psig. After exiting the pump, the liquid hydrocarbon product stream can be passed into indirect heat exchange with the dehydrogenation effluent at the first plate-fin heat exchanger. As a result, the temperature of the liquid hydrocarbon product stream can be raised to about 80° F. The liquid hydrocarbon product stream can be recovered or sent downstream for further processing, such as fractionation.
The hydrogen-containing vapor phase resulting from the first vapor-liquid separator is a relatively impure hydrogen gas stream containing significant amounts of low molecular weight hydrocarbons, e.g., methane and ethane. The hydrogen-containing vapor phase has a hydrogen concentration of about 80 mole %.
In a preferred embodiment of the present invention, the hydrogen-containing vapor phase is passed to a second plate-fin heat exchanger for additional indirect heat exchange prior entering the next separation stage. This second plate-fin heat exchanger reduces the temperature of the hydrogen-containing vapor phase to about -150° to -250° F.
In accordance with the present invention, the hydrogen-containing vapor phase is contacted in a cold absorption zone with a lean liquid absorbent comprising C 2 -C 5 hydrocarbons, preferably C 2 -C 5 paraffinic hydrocarbons. As previously mentioned, the present invention contacts the hydrogen-containing vapor phase with the lean liquid absorbent under very cold conditions. Accordingly, the temperature of the cold absorption zone is maintained at a temperature of less than about -120° F., preferably less than about -200° F., most preferably less than about -250° F. A suitable operating pressure for the cold absorption zone can be about 100 psig.
In a preferred embodiment, the hydrogen-containing vapor phase and the liquid absorbent are contacted in a countercurrent absorption zone, i.e., the upflowing vaporous materials of the hydrogen-containing vapor phase are intimately contacted in a countercurrent fashion with a descending stream of the liquid absorbent. Accordingly, in the countercurrent absorption zone, a relatively impure hydrogen-containing gas stream containing significant amounts of low molecular weight hydrocarbons passes upwardly through a plurality of contacting stages and the hydrocarbon portions of which are selectively absorbed by the downwardly passing relatively heavy hydrocarbons contained in the lean liquid absorbent.
The products of the absorption zone are a methane-rich absorber liquid (containing most of the hydrocarbons in the hydrogen-containing vapor stream) and a hydrogen-rich gas stream. In a preferred embodiment, the methane-rich absorber liquid is passed to the second plate-fin heat exchanger for indirect heat exchange (which increases the temperature of the methane-rich absorber liquid to about -120° F.) and directed to a third vapor-liquid equilibrium separation zone that is operated at a pressure of about 20 to 50 psig. An overhead vapor stream rich in methane exits the top of the third vapor-liquid separation zone. This overhead stream can be passed to the first plate-fin heat exchanger and may be compressed, if necessary, to enter an existing fuel gas system.
Exiting the bottom of the third vapor-liquid equilibrium separation zone is the lean liquid absorbent that can be recycled to the cold absorption zone. In a preferred embodiment, the lean liquid absorbent is pumped into a second plate-fin heat exchanger for indirect heat exchange prior to being recycled to the absorption zone.
In accordance with the present invention, the hydrogen-rich gas stream exits the top of the absorption zone and is subjected to refrigeration. Any suitable refrigeration means known to those skilled in the art may be employed. In a preferred embodiment, the means for refrigerating the hydrogen-rich gas stream is gas expansion with shaft work that removes energy. In this gas expansion mode, the hydrogen-rich gas stream enters a gas expander having a generator with a common shaft between the generator and the gas expander. The hydrogen-rich gas stream enters the gas expander at a pressure of about 60-200 psig causing the turbine to rotate (similar to the operation of a pinwheel). This in turn causes the shaft to rotate, thereby removing work energy from the hydrogen-rich gas stream and reducing the temperature of the hydrogen-rich gas stream from about -150° F. to about -280° F. The relatively high pressure drop across the gas expander causes the hydrogen-rich gas stream to exit the expander at a pressure of about 40 psig.
After refrigeration, the hydrogen-rich gas stream is preferably passed to the second plate-fin heat exchanger for indirect heat exchange. Such heat exchange increases the temperature of the hydrogen-rich gas stream to a temperature of about 10° to -125° F.
The hydrogen-rich gas stream can then be split into two streams, a net hydrogen stream and a hydrogen recycle stream. In a preferred embodiment, the net hydrogen stream is directed to the first plate-fin heat exchanger for indirect heat exchange prior to use in other hydrocarbon conversion processes located in the refinery.
The hydrogen recycle stream can be admixed with the hydrocarbon liquid component of the dehydrogenation feed stream. In a preferred embodiment, the hydrocarbon liquid is passed to the first plate-fin heat exchanger for indirect heat exchange prior to admixing with the hydrogen recycle gas. After admixing, the admixture can be passed to the first plate-fin heat exchanger prior to being routed to the dehydrogenation section of the present invention.
The further description of the process of this invention is presented with reference to the attached drawing. The drawing represents one preferred embodiment of the invention and is not intended as an undue limitation on the generally broad scope of the invention as set out in the appended claims.
Referring to the drawing, a hydrocarbon feed stream comprising C 2 -C 5 paraffinic hydrocarbons enters a first aluminum plate-fin heat exchanger 14 via line 2 at a temperature of about 100° F. After exiting the heat exchanger 14 by line 3 at temperature of about -120° F., the hydrocarbon feed stream is admixed with a recycle hydrogen stream via line 11 to form an admixture feed stream 8. This admixture feed stream enters the heat exchanger 14 at line 8 at a temperature of about -122° F. and exits the heat exchanger 14 by stream 1 at a temperature of about 80° F. After exiting the heat exchanger 14, the heated admixture feed stream enters the dehydrogenation section 4 via line 1.
Although in the figure the dehydrogenation section 4 is shown only as a single box, it consists of at least one dehydrogenation reactor and an assortment of pre-reactor heat exchangers, pre-reactor activated aluminum beds for removing impurities, interstage heaters and post-reactor coolers (all not shown). Also included in the dehydrogenation section 4 is at least one dehydrogenation effluent compressor (not shown) that increases the pressure of the effluent up to about 100 psi.
In any event, a compressed, effluent stream exits the dehydrogenation section 4 via line 12 at a temperature of about 100° F. and a pressure of about 100 psi. This effluent stream entering at line 12 is then routed to the first plate-fin heat exchanger 14 and is therein passed into indirect heat exchange with the previously mentioned feed stream admixture which enters the heat exchanger 14 via line 8.
After exiting the heat exchanger 14, the compressed, cooled effluent is introduced via stream 16 to a high pressure vapor-liquid separator 22. The vapor-liquid separator is operated at a temperature of about -120° F. and a pressure of about 100 psig. Exiting the bottom of the separator 22 in stream 24 is a liquid phase comprising a substantial amount of C 2 -C 5 olefinic hydrocarbons as well as unreacted paraffinic hydrocarbons. This liquid phase 24 is then passed to a low pressure vapor-liquid separator 26 that operates at a pressure of less than about 5 psig. Exiting the top of the low pressure separator 26 in line 25 is a stream comprising hydrogen and light hydrocarbons. The overhead stream then enters the first plate-fin heat exchanger 14 at line 25 where it is passed into indirect heat exchange with the dehydrogenation section effluent stream 12. Exiting the first plate-fin heat exchanger 14 at line 27, the heated overhead stream, having a temperature of about 80° F., is then recycled to the dehydrogenation section 4.
Exiting the bottom of the low pressure separator 26 in stream 30 at a temperature of about -120° F. is a liquid product stream 30 comprising predominantly C 2 -C 5 olefinic hydrocarbons as well unreacted paraffinic hydrocarbons. This liquid product stream is then passed via stream 30 into a liquid product pump 31 that increases the pressure of the liquid product stream to about 200-300 psig. After exiting the liquid product pump 31 by line 33, the compressed, liquid product stream is passed into the first plate-fin heat exchanger 14 where it is brought into indirect heat exchange with the dehydrogenation effluent 12. As a result, the temperature of the liquid product stream is raised to about 80° F. The liquid product stream exits the heat exchanger 14 at line 35 and is sent downstream for further processing, such as fractionation.
A hydrogen-containing vapor phase exits the high pressure separator 22 via line 34 and is passed to a second plate-fin heat exchanger 36 where the hydrogen-containing vapor phase is passed in indirectheat exchange with a hydrogen-rich gas stream which enters the heat exchanger 36 at line 57. The hydrogen-containing vapor phase enters the second plate-fin heat exchanger 36 at stream 34 at a temperature of about -120° F. and exits the plate-fin heat exchanger 36 via stream 37 at a temperature of less than about -250° F.
The cooled, hydrogen-containing vapor phase is then introduced into the bottom of a cold absorber column 38 by line 37. Near the top of the absorber column 38, a lean liquid absorbent stream comprising C 2 -C 5 paraffinic hydrocarbons and a small amount of methane is introduced by line 45 in a fashion countercurrent to the flow of the hydrogen-containing vapor phase at a temperature of about -250° F. and a pressure of about 100 psi. A methane-rich liquid absorbent exits the bottom of the absorber column 38 via line 42 at temperature of less than about -250° F. and is passed to the second plate-fin heat exchanger 36 where it is brought into indirect heat exchange with the hydrogen-containing vapor phase.
The methane-rich liquid absorbent exits the bottom of second plate-fin heat exchanger 36 at a temperature of less than about -120° F. via line 44 and enters an intermediate pressure vapor-liquid separator 46 where a methane-rich gas stream is removed overhead via line 48. The intermediate pressure separator 46 operates at a pressure of about 20 psig. The methane-rich gas stream is then introduced to first plate fin heat exchanger 14 via line 48 wherein it is passed into indirect heat exchange with an effluent stream from the dehydrogenation section of the present invention. A warmed, methane-rich gas stream exits the first plate heat exchanger 14 via stream 60 and is directed to the fuels section of the refinery.
The lean liquid absorbent exits the intermediate pressure vessel 46 at a temperature of less than about -120° F. by line 40. The liquid absorbent is then introduced to a lean liquid absorbent pump 39 that increases the pressure of the lean liquid absorbent from about 20 psig to about 100 psig. The lean liquid absorbent exits the pump 39 via line 43 and is passed to the second plate-fin heat exchanger 36 wherein it is brought into indirect heat exchange with the methane-rich liquid absorbent. As a result, the temperature of the cooled liquid absorbent is lowered from about -120° F. to about -250° F. The cooled liquid absorbent is then directed back to the top the absorber 36 via stream 45.
A hydrogen-rich gas stream exits the top of the absorber column 38 via line 54 and is transferred to a gas expander 56. Exiting the gas expander 26 at a temperature of about -280° F. and a pressure of about 40 psi via stream 57, the hydrogen-rich gas stream is directed to the second plate-fin heat exchanger 36 wherein the hydrogen-rich gas stream is passed into indirect heat exchange with the hydrogen-containing vapor phase. The hydrogen-rich gas stream exits the plate-fin heat exchanger 36 via line 6 at a temperature of about -125° F.
At junction 7, the hydrogen-rich gas stream is split into two separate stream, the net hydrogen stream 9 and the recycle hydrogen stream 11. The net hydrogen stream is subsequently passed to the first plate-fin heat exchanger 36 prior to being sent to other hydrocarbon conversion processes located in the refinery via line 61. The recycle hydrogen stream 11 is then admixed with the cooled, hydrocarbon liquid stream 3 to form the admixture 8. The admixture 8 is then passed to the first plate-fin heat exchanger 14 for indirect heat exchange with the dehydrogenation effluent stream. The heated admixture exits the first plate-fin heat exchanger 14 in stream 1 and is then directed to the dehydrogenation section 4.
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Purified hydrogen is recovered from the effluent of a catalytic dehydrogenation zone using an integrated cold absorption process. The effluent, which contains olefinic hydrocarbons and hydrogen is compressed, cooled and contacted with a liquid absorbent. The purified hydrogen can be recycled to the dehydrogenation zone and the olefinic hydrocarbons are recovered as product. The present invention will recover higher purity hydrogen and liquefiable hydrocarbons more economically than prior art processes.
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SUMMARY OF THE INVENTION
This invention relates to a novel process for the manufacture of geranyl chloride, also known by its synonym, 8-chloro-2, 6-dimethyl-2,6-octadiene. This compound is useful as an intermediate in the manufacture of the epoxides of certain geranylphenyl ethers which are known for their usefulness in controlling insects by exerting a disrupting influence upon the normal development of the insects. A description of these epoxides of geranylphenyl ethers and the use of geranyl chloride in their manufacture is found in U.S. Pat. No. 3,825,602. The present invention relates to a process for the manufacture of geranyl chloride which is both economical and results in a product of a high degree of purity.
BACKGROUND OF THE INVENTION
A wide variety of processes are known in the art for the preparation of geranyl chloride. The compound can be prepared from myrcene by hydrohalogenation in the presence of a Cu catalyst (U.S. Pat. Nos. 3,016,408 and 2,871,271). It can also be prepared from linalool by reaction with SOCl.sub. 2, PCl.sub. 3, PCl.sub. 5, COCl.sub. 2, or HCl. Geraniol has also been used extensively as the starting material, most notably by treatment with PCl.sub. 3 or PCl.sub. 5 [L. Ruzicka, Helvetica Chim. Acta 6, 483-92 (1923)], and by treatment with a mixture of methanesulfonyl chloride, lithium chloride and dimethylformaide [E. W. Collington and A. I. Meyers, J. Org. Chem 36 (20), 3044 (1971)].
Many of the above reactions give extensive rearrangement products including elimination products. Others are costly and impractical as commercial processes.
The process of the present invention provides the advantage of favorable process economics, and produces the desired product in very high purity and yields.
DESCRIPTION OF THE INVENTION
In the practice of the present invention, geraniol, also known by the synonym 2,6-dimethyl-2,6-octadiene-8-ol is reacted with chlorodimethylformiminium chloride to produce geranyl chloride.
The invention relates to the above reaction regardless of the methods of preparation of the starting materials. An example of the preparation of chlorodimethylformiminium chloride is the reaction between, N,N-dimethylformamide with phosgene gas. Since the latter reaction also produces gaseous HCl, its efficiency and stoichiometry will be enchanced if the rate of addition of the gaseous phosgene is slow enough to prevent the HCl produced from sweeping out of the reaction mixture any substantial amount of the phosgene. The chlorodimethylformiminium chloride reaction preferably occurs in the presence of a non-reactive solvent, for example benzene, toluene, chloroform, methylene chloride, ethylene dichloride, carbon tetrachloride, hexane, pentane, etc. The use of a solvent will serve to moderate the reaction and to shield the resultant product from exposure to air, thus preventing the reaction between chlorodimethylformiminium chloride and the moisture in the air. Exposure to moisture can also be prevented by running the chlorodimethylformiminium chloride reaction in an atmosphere of ivert dry gas, e.g., nitrogen or dry air.
The process of the invention, the reaction between geraniol and chlorodimethylformiminium chloride, can also be conducted in the presence of a nonreactive solvent which will serve the function, among others, of moderating the reaction. When the reactions to form chlorodimethylformiminium chloride and geranyl chloride are performed in succession, it will be convenient to use the same solvent for both reactions.
In reactions performed subsequent to the process of the invention, for instance, whereby geranyl chloride is further reacted to form an epoxide as mentioned in the Summary of the Invention above, the same solvent can again be used. The yield of the epoxide can be improved, however, by removal of any light ends formed in the geranyl chloride reaction prior to the formation of the epoxide. Further purification can be done either before or after the epoxide reaction or any other reaction performed subsequent to the formation of geranyl chloride.
The particular temperature and pressure at which the reaction to form geranyl chloride is performed are not essential to the process of the invention. The reaction temperature is primarily limited by the melting and boiling points of the solvent used; it is generally convenient to run the reaction at a temperature between about 0° and about 80° C, with about 20° to about 40° C preferred. Likewise, it will be convenient to use a pressure ranging from about 0.8 to about 4.0 atmospheres.
The reaction can be conducted with approximately equimolar amounts of geraniol and chlorodimethylformiminium chloride. An excess of either of the reactants can also be used. In particular, an excess of the chlorodimethylformiminium chloride will provide the advantage of complete removal of geraniol from the system. This will be a desirable result when the geranyl chloride thus formed is further reacted to form the epoxide and subsequently the phenyl ether as described in U.S. Pat. No. 3,825,602.
When a solvent is used, the reaction mixture will form two liquid phases, with the desired product, geranyl chloride, residing in the upper phase. These phases can be separated by decantation or any other conventional separation technique, and, if desired, the product can be recovered from the upper phase and purified, by conventional purification procedures, such as evaporation or distillation. When no solvent is used, the geranyl chloride will itself form an upper phase which can be separated and purified in the same manner as indicated above.
Optionally, a quenching reagent can be added to either or both phases at any point in time after the reaction. When the above-described chlorodimethylformiminium chloride reaction is used, a quenching reagent can also be used after such reaction. The reagent in either case will be a weak base, for example a 10% sodium carbonate solution or a 5% sodium hydroxide solution. The base will serve to neutralize any acidic species remaining in solution and thus improve the stability of the desired product.
The following example is offered to further illustrate the process of the invention.
EXAMPLE
Into a 2-liter round bottom flask was placed 176 g (2.40 moles) anhydrous dimethylformamide (DMF) and 800 ml dry benzene. Phosgene gas (210 g, 2.10 moles) was bubbled into the solution over a period of 8 hours. As the reaction progressed, chlorodimethylformiminium chloride precipitated as a white solid. The reaction was mildly exothermic and the temperature of the reaction rose from 24° to 36° C. When the phosgene addition was complete, anhydrous granular sodium carbonate (5.3 g, 0.05 mole) was added to the solution.
Next, 310 g (2.0 moles) geraniol (92% pure) was added over a period of 35-40 minutes and the reaction was moderated by an ice-water bath. The solid dissolved and a clear light yellow-brown solution resulted. The solution was stirred for several hours. The resulting mixture was analyzed by vapor phase chromatography, which showed about 3 area percent unreacted geraniol. An additional 8 g of phosgene served to eliminate any detectable amounts of geraniol in the reaction mixture.
The reaction mixture formed two liquid phases, the lower of which, containing DMF, chlorodimethylformiminium chloride and sodium carbonate, was drawn off and discarded. The upper phase was washed with aqueous 10% sodium carbonate solution and subsequently with water. The solvent was then evaporated from the mixture to give a product of the following analysis in area percent by vapor phase chromatography
______________________________________Light ends 2.7%Linalyl chloride 8.4%Neryl chloride 9.7%Geranyl chloride 73.2%Heavy ends 3.7%Geranyl dichloride 2.0%______________________________________
The weight of geranyl chloride was 342 g (98% technical yield).
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A novel process for the manufacture of geranyl chloride, a useful intermediate in the manufacture of compounds useful in controlling insects, which comprises reacting geraniol and chlorodimethylformiminium chloride to produce the desired product.
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BACKGROUND OF THE INVENTION
Thermostats that control heating and air conditioning units typically have a temperature control range of forty to sixty degrees. It is often desirable to restrict the temperature range within which the thermostat can be operated. Toward this end, thermostat range limit devices have been proposed.
Examples of such devices are found in U.S. Pat. No. 4,639,709 issued to Koets and U.S. Pat. Nos. 4,090,165 and 3,999,158 issued to Rae. These devices narrow the range within which the thermostat control lever can operate and thereby restrict the range within which the temperature setting swings. These devices are relatively simple and efficient. However, they do suffer from major drawbacks.
The thermostat must be constrUCted so that it receives the particular range limit device. Therefore, in order to make use of these range limit devices, the thermostat housing must be able to receive the device. Otherwise, the housing must be retrofitted with the receiving means.
Furthermore, each of the above devices requires a partial disassembly of the thermostat housing in order to reset the range. Additionally, the two devices proposed by Rae require the storage of several parts to be used for the various ranges desired. Such parts will tend to be lost over time rendering the device useless.
The above drawbacks associated with the current range limit devices, will discourage installation and use of the devices. If a thermostat's housing is unable to receive a temperature range limit device, a person will be loath to pay for a retrofit. If the device is installed, many people will disassemble the thermostat housing in order to utilize the device.
What is needed is a thermostat range limit device that does not require any particular receiving means within the thermostat housing. Such a device must be able to be installed on any thermostat without the need for any alteration to the thermostat. This device must be easy to use without the need to partially disassemble the housing. Ideally, this device should be inexpensive to manufacture.
SUMMARY OF THE INVENTION
This invention provides for a thermostat range limit device that will allow for an easy means of limiting the temperature range within which a thermostat can be operated. The temperature range limit device of the present invention includes a base, a high temperature limit means, and a low temperature limit means.
The base is attached to the top, side, or bottom of a conventional thermostat, depending on whether the thermostat's temperature control lever is top, side, or bottom mounted. The high temperature limit means and the low temperature limit means are releasably attachable to the base. The high temperature limit means can be placed along the base to correspond to the highest desired temperature to which the thermostat can be set. The low temperature limit means can be placed along the base to correspond to the lowest desired temperature to which the thermostat can be set.
The high temperature limit means, which sets the high temperature limit, and the low temperature limit means, which sets the low temperature limit, block further advancement of the temperature control lever beyond the desired settings. The temperature control lever operates between the high temperature limit means and the low temperature limit means. Once the temperature range is set by the respective temperature limit means, the temperature lever cannot be pushed outside the range.
Therefore, it is the object of the present invention to provide for a thermostat range limit device that is easy to install onto any conventional thermostat without the need to retrofit the thermostat housing.
It is another object of the present invention to provide for a thermostat range limit device that will permit easy access to and change of the range limit settings without the need to disassemble the thermostat housing.
It is another object of the present invention to provide for a thermostat range limit device that will be easy and convenient to reset in the dark or by person that are presbyopic or have deficient eye sight.
It is another object of the present invention to provide for a thermostat range limit device that is inexpensive to fabricate and durable in operation.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1a is a front elevation view of one embodiment of the thermostat range limit device of the present invention,
FIG. 1b is a front elevation view of the base of the thermostat range limit device having an altered center area.
FIG. 2a is a side elevation view of one embodiment of the thermostat range limit device of the present invention.
FIG. 2b is an alternative side view of the base of the thermostat range/limit device of the present invention.
FIGS. 3a-3c are isometric views of the temperature limit means which can be used in the various embodiments of the thermostat range limit device of the present invention.
FIGS. 4a and 4b are side views of the securing means used in the various embodiments of the thermostat range limit device of present invention.
FIG. 5 is a perspective view of another embodiment of the present invention.
FIG. 6 is a front elevation view of the embodiment of FIG. 1a of the thermostat range limit device of the present invention installed parallel to the side of a conventional thermostat.
FIG. 7 is a front elevation view of the thermostat range limit device of the present invention attached to the bottom of a conventional thermostat.
FIG. 8 is a front elevation view of another embodiment of the thermostat range limit device of the present invention.
FIG. 9 is a front elevation view of the thermostat range limit device of FIG. 8 installed to the top of a conventional thermostat.
Similar reference numerals refer to similar parts throughout the several views of the drawings.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIGS. 1a-2b illustrate the various views of the present invention. As seen in these figures, the thermostat range limit device 10 of the present invention consists of a base 12, a high temperature limit means 14, and a low temperature limit means 16.
The base includes a front side 22, a back side 24, a first end 18 and a second end 20. The base further includes a top edge 28, bottom edge 30, and a middle portion 26.
Centrally located on middle portion of the base is an opening means for receiving the securing means 32. In one embodiment, the opening means in the middle portion of the base is a plurality of evenly spaced holes 34 (illustrated in FIG. 1). Optionally, the opening means can include a groove 36 which extends from the front side 22 to the back side 24 of the base. This groove 36 is illustrated as the opening means in FIG. 1b.
A first attachment means 38 is located on the back side at the first end of the base and a second attachment means 40 is located on the back side at the second end of the base. The first and second ends of the back side of the base are securely fastened to the wall by utilizing the first and second attachment means 38, 40. The base of the thermostat range limit device is positioned in the proximity of the conventional thermostat housing so that the high or low temperature limit means will be able to contact the thermostat's temperature control lever.
Alternatively, the base 12 can be directly fastened to the housing of the conventional thermostat. In order to provide for this type of arrangement, the base of the thermostat range limit device is altered. This alteration is illustrated in FIG. 2b. As seen in FIG. 2b, the back side 24 of the base can include a first set of grooves 42 and a second set of grooves 44. The first set of grooves 42 is located near the first end 18 of the base and next to the first attachment means 38. The second set of grooves 44 is located near the second end 20 of the base and next to the second attachment means 40. Both the first and second set of grooves extend from the top edge 28 to the bottom edge of the base. This configuration will permit the base to bend easily at the location of the first and second set of grooves. This bending will provide for the first and second ends to be perpendicular to the middle portion 26 of the base. This arrangement will provide for the first and second ends of the base to be attached to the side walls of a conventional thermostat, while the middle portion faces the thermostat's temperature control lever. An example of the utilization of the thermostat range limit device having a first set of grooves and a second set of grooves on the back side of the base is illustrated in FIG. 9.
The high temperature limit means 14 and the low temperature limit means 16 are secured to the base. Both the high and low temperature limit means can slide freely on the base once the securing means are removed. The various embodiments used for the high temperature limit means are illustrated in further detail in FIGS. 3a-3c. The low temperature limit means is not separately illustrated in that it is identical in shape, size, structure, and design as the high temperature limit means.
FIGS. 4a-4c are the various embodiments of high temperature limit means that can be utilized with the thermostat range limit device illustrated in FIGS. 1a-2b.
FIG. 3a illustrates the first embodiment of the high temperature limit means. As seen in this figure, the high temperature limit means has a first curve end 46 and a second curved end 48. A first wall 50 and a second wall 52, which are parallel to each other, are located between the first curved end and the second curved end. This first embodiment of the high temperature limit means further includes a hollow center 54. This hollow center receives the base of the thermostat range limit device. A first hole 56 and a second hole (not illustrated) are centrally located on the first and second wall, respectively. The first and second holes are aligned with each other and receive the securing means.
In order to adjust the temperature range of the thermostat range limit device when the first embodiment of the temperature limit means is used, the securing means is first removed. This will unlock the temperature limit means and allow it to slide freely on the base. Once the desired temperature range is selected, the securing means is inserted through the first hole, the opening means provide in the base (plurality of holes illustrated in FIG. 1a or the groove illustrated in FIG. 1b) and the second hole. This will provide for the high and low temperature limit means to be in a fixed position. This securing means is illustrated in FIGS. 4a and 4b.
As seen in FIG. 3b the high temperature limit means is U-shaped. This U-shape limit means has a first curved end 46, an open end 58, a first wall 50, and a second wall 52. The first wall has a first side (not illustrated) and a second side 60. The second wall has a first side (not illustrated) and a second side 62. The first side of the first wall faces the second side 62 of the second wall. This first side of the first wall and the second side of the second wall constitutes the interior of the limit means while the second side of the first wall and the first side of the second wall constitutes the exterior of the limit means. A first hole 56 and a second hole (not illustrated) are centrally located in the first and second wall, respectfully. The first hole is aligned with the second hole.
The high temperature limit means and the low temperature limit means are releasably attachable to the base. In order to attach and adjust the temperature limit means to the base, the open end 58 of the temperature limit means is straddled onto the front and back sides of the base. This causes the second side of the first wall and the first side of the second wall to directly contact the base. A force is exerted on the exterior of the curved end of the U-shape temperature limit means to provide for the interior of the curved end to communicate with the top edge of the base. Upon attachment to the base, the temperature limit means can slide freely about the base. Once the desired temperature is obtained for the high and low temperature limit means, the securing means is inserted into the first hole, the opening means, and the second hole in order to provide for the high and low temperature limit means to be in a locked position. This securing means is illustrated in further detail in FIG. 5.
A third embodiment of the temperature limit means is illustrated in FIG. 3c. This embodiment is a slight variation of the second embodiment of the temperature limit means. As seen in this figure, the difference resides only in that the second wall, attached to the curved top end of the temperature limit means, is crimped. This crimped portion 64 provides a gripping area for the user and will provide a facilitation in the adjusting of the temperature limiting means. This embodiment of the temperature limit means operates in the same manner as the temperature limit means illustrated and discussed in FIG. 3b.
The securing means that can be used in the embodiment illustrated in FIG. 1a is illustrated in FIG. 4a. As seen in this figure, the securing means 32 has a top portion and a bottom portion. The bottom portion is an elongated solid rod 66 which has a smaller diameter than the holes located on the base and the holes located on the high and low temperature limit means. The top portion 68 of the securing means has a solid semi-circular shape. The top portion also includes a diameter which is larger than the diameter of the bottom portion of the securing means, the holes located on the base, and the holes located on the high and low temperature limit means. The bottom portion of the securing means is received in the holes of the base and the holes of the high and low temperature limit means. This securing means maintains the high and low temperature limit means in the desired location.
The embodiment illustrated in FIG. 4a can be changed in order to provide for a securing means to be utilized with the embodiment illustrated in FIG. 1b. As seen in FIG. 4b, the securing means 32 consists of a semi-circular shaped top 68. Attached to the flat surface of the top is an elongated threaded rod 70. The bottom portion of the securing means is received in the holes of the high and low temperature limit means as well as in the groove. The teeth located on the threaded rod will cut slightly into the walls of the groove to provide for the high and low temperature limit means to be affixed on the base in a locked position.
It is noted that only one securing means is illustrated in FIG. 4. This is because the securing means used to lock the high and low temperature limit means in a fixed position are identical in shape, structure, size and design
The preferred embodiment of the thermostat range limit device is illustrated in FIG. 5. In this embodiment, the thermostat range limit device 10 includes a base 12, a high temperature limit means 14, and a low temperature limit means 16.
The base include a front side 22, a back side (not illustrated), a first end 18 and a second end 20. Located on the back side at the first end is a first attachment means 38 and located on the back side at the second end is a second attachment means 40.
The high temperature limit means 14 and the low temperature limit means 16 are secured to the base. As illustrated in this figure, the high and low temperature limit means are identical in shape, size, and design.
Each temperature limit means further include a first wall 50, a second wall 52, a curved top end 46 and a bottom area 72. A first hole 56 and a second hole (not illustrated) are located on the bottom area of the first and second walls, respectively. The first and second holes are co-aligned with each other. As further illustrated, the bottom area of the first wall has an indented portion 74. This indentation is in the direction of the second wall, causing the bottom area of the first wall to be concave.
The high and low temperature limit means are releasably attachable to the base. In order to attach the limit means to the base, the first and second sides of the temperature limit means is straddled onto the front and back side of the base. Each temperature limit means is pushed down until the inside of the curved top portions contacts the top edge (not labeled in this figure) of the base. This causes the bottom area of the temperature limit means to extend beyond the base.
The high and low temperature limit means are then able to slide freely along the base. The high and low temperature limit means are then situated on the base at the desired location (dependent on the desired temperature). A securing means (illustrated in FIGS. 4a and 4b) is inserted into the first and second holes. During the process of inserting the securing means into the first and second holes, the first and second walls are moved inwardly. This inherently causes the first and second walls to tighten around the base. The process of inserting the securing means into the first and second holes is continued until the first and second holes are in direct contact with each other. This contact will provide for the temperature limit means to fit securely around the base.
It is noted that if the securing means illustrated in FIG. 4b is used, then the first and second holes on the high and low temperature limit means will be threaded.
The attaching means used in the embodiments illustrated in FIGS. 1a, 1b, and 5 can include a variety of conventional attaching elements, such as, but not limited to, screws, adhesives, double-face gluable pad, cooperating fabric hook and fabric loop material (Velcro), and any other commercially available attachment means.
The attachment means illustrated in FIGS. 2a and 2b is cooperating fabric hook and loop material. As shown in these figures, cooperating fabric hook material is attached to the back side of the base, while the cooperating fabric hook material would be attached to the wall.
It order to utilize the thermostat range limit device of the present invention as illustrated in FIG. 6, the attachment means, located on the back of the base, is attached to the wall in the proximity of a conventional thermostat 76. It is noted that the curved ends 46 of the high and low temperature limit means face the conventional thermostat device. The base is attached parallel to the thermostat so that the limit means can contact the temperature control lever 78. The high and low temperature limit means are aligned with the respective temperatures desired. The securing means 32 is then inserted into the holes of the base and the holes of the high and low temperature limit means, thereby locking the limit means into a fixed position and allowing the thermostat range limit device 10 to be utilized.
The thermostat range limit device can be readjusted at any time. In order to do so, the securing means are removed from the high and low temperature limit means. The high and low temperature limit means can then slide freely along the base. Once the new desired temperature settings are obtained, the securing means are inserted into the holes of the base and the holes of the high and low temperature limit means. Thus locking the limit means into a fixed position.
The thermostat limit device can be attached directly to the thermostat. This attachment is illustrated in FIG. 7. As is seen in this figure, the embodiment illustrated in FIG. 2b is attached to the side walls of a conventional thermostat. It order to secure the thermostat range limit device to the conventional thermostat, the first and second ends of the base are bent inwardly. The bending occurs at the location of the first and second set of grooves 42,44. The attachment means (38,40) located on the back of the base, is then affixed to the side walls of the conventional thermostat 76. The middle portion 26 of the base is parallel to the thermostat so that the high and low temperature limit means (14, 16) can contact the temperature control lever 78. The high and low temperature limit means are aligned with the respective temperatures desired. The securing means is then inserted into the holes of the base and the holes of the high and low temperature limit means, thereby locking the limit means into a fixed position and allowing the thermostat range limit device 10 to be utilized.
In order to accommodate the various shapes that are utilized with conventional thermostats, the base of the thermostat range limit device of the various embodiments illustrated in FIGS. 1a, 1b, and 5 can be adjusted. One example of such an alteration is illustrated in FIGS. 8 and 9.
The difference between the embodiment illustrated in FIGS. 1a, 1b, and 5 and the embodiment illustrated in FIGS. 8 and 9 resides only in the shape of the base. As illustrated, the shape of the base 12 can be altered to conform to the shape of any conventional thermostat. This figure shows that the base is arched. The attachment of the thermostat range limit device 10 is in the proximity of the conventional thermostat device 76. This attachment is done in the same manner as discussed and illustrated in the previous figures.
While the invention has been particularly shown and described with reference to an embodiment thereof, it will be understood by those skilled in the art that various changes in form and detail may be made without departing from the spirit and scope of the invention.
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An adjustable thermostat range limit apparatus consists of a base member having a pair of adjustable temperature limit means. The thermostat range limit apparatus is attached in the proximity of a conventional thermostat so that the adjustable temperature limit means can come into contact with the temperature control level of a conventional thermostat. These adjustable temperature limit means will provide for a restriction in the temperature range in which the temperature control lever can be set.
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BACKGROUND OF THE INVENTION
The present invention relates to analog signal processing systems, and particularly to systems for changing the frequency of analog signals in a real-time manner. For purposes of example, the invention is described below with respect to two types of systems, namely as an aid to hearing by a person having a limited-frequency audibility, and as a means for communicating audio signals in a manner non-intelligible except by a properly equipped receiver. It will be appreciated, however, that the invention could also be used in other applications, for example in the analysis of transient signals.
With respect to the first of the above-mentioned applications, it is to be noted that the upper limit of human audibility is usually about 15-20 kHz, but many persons have a much more limited range and are not able to hear tones within this frequency range. The invention, as to be described more fully below, is particularly useful in this type of application for the real-time reduction of the frequency of audio signals to a range which a person, having such a hearing deficiency, is capable of hearing.
With respect to the second of the above-mentioned applications of the invention, various secret communication systems have been proposed for scrambling information transmitted, e.g. by a radio transmitter, so as to render the information unintelligible except by a properly equipped receiver. Such scrambling systems are quite costly and therefore have limited application. The invention may be used for simplifying and reducing the cost of secret communication systems.
BRIEF SUMMARY OF THE INVENTION
According to a broad aspect of the present invention, there is provided an analog processing system comprising at least two analog shift registers each capable of storing, under the control of loading clock pulses, an analog signal in the form of a plurality of analog samples, and of outputting them under the control of unloading clock pulses. The system further includes an input circuit connected to the input end of all the analog shift registers in parallel, and an output circuit selectively connectible to the output ends of the analog shift registers. The system further includes a source of high frequency clock pulses, a source of lower frequency clock pulses, and cyclically operable switching means effective, during one phase of each cycle, to connect at least one analog shift register to one source of clock pulses to load same at the rate corresponding to the frequency of that source, and to connect at least one other analog shift register to the other source of clock pulses and to the output circuit to unload the other register at the rate corresponding to the frequency of that source. The latter switching means are also effective, during another phase of each cycle, to change the connections with respect to the two sources of clock pulses, so that the analog shift register loaded in the first phase is now unloaded, and visa versa.
For the analog shift registers, there may be used the recently developed charge-transfer devices which operate by the movement of a charge packet from one capacitor stage to an adjacent capacitor stage by the application of clock pulses. Thus, an analog signal may be inputted at a first rate by the application of clock pulses having one frequency, and may be outputted at a second rate by the application of clock pulses having a second frequency. In such devices, while the inputted signal is sampled in time, as in conventional digital processing, the amplitude of the signal is retained in analog form. As one example, there may be used the Phillips TDA 1022, having 512 stages and operable with clock frequencies in the range of 5 kHz to 500 kHz. In many applications, it may be desirable to increase the number of stages by providing each analog shift register with two or more of such units.
As indicated earlier, the invention is particularly useful for changing the frequency of audio signals in a real-time manner. In such applications, the output circuit would further include a low-pass filter which substantially reconstructs the original analog signal but at the different frequency, determined by the frequency relationship of the two clock pulses.
One particularly useful application of the invention is as a hearing aid device to reduce the frequency of audio signals in a real-time manner, and thereby to aid those persons having a limited-frequency audibility. In such an application, the system would include two analog shift registers, and the switching means would be effective during each of two phases to load one register at the high-frequency clock pulse rate, while unloading the other register at the lower-frequency clock pulse rate.
When the system is used in the above-described hearing-aid application, the results are somewhat like recording an audio signal at one frequency and playing it back at a lower (e.g. one-half) frequency, except that in the present invention the frequency-division is effected in a real-time manner. That is to say, when the audio signal is recorded at one speed and played back at one-half speed, the play-back cannot start until the recording has been completed, and moreover, the play-back takes twice as long as for recording. In the present invention, however, the recording and play-back occur substantially simultaneously, although there is a very slight delay, in the order of milliseconds.
The invention may also be applied to increase the frequency of analog signals in a real-time manner, for example to transmit the signals at a sufficiently high frequency so as to be undetectable or unintelligible to a receiver not equipped with an approximate real-time low-frequency converter. In the high-frequency converter application, there would be at least three analog shift registers and at least three phases, the switching means being effective, during each of the three phases, to unload one analog shift register at the high-frequency clock pulse rate, while loading the other two registers at the low-frequency clock pulse rate.
Preferably, the frequency of the low-frequency clock pulses is one-half that of the high-frequency clock pulses. In such systems, therefore, the frequency change effected in a real-time manner is by a factor of "2". It may be desirable to increase this factor, which can easily be done, for example, by connecting a plurality of such system in tandem.
Further features, advantages and applications of the invention will be apparent from the description below.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is herein described, by way of example only, with reference to the accompanying drawings, wherein:
FIG. 1 is a block diagram illustrating, in generalized form, a real-time frequency-reducing circuit constructed in accordance with the invention;
FIG. 2 is a block diagram illustrating one implementation of the system of FIG. 1;
FIG. 3 is a block diagram illustrating a real-time frequency-multiplying circuit constructed in accordance with the invention; and
FIG. 4 is a block diagram illustrating a communication system constructed in accordance with the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
With reference first to FIG. 1, there is shown a real-time frequency-reducing circuit particularly useful for reducing the frequency of audio signals for a person having a limited-frequency audibility. Briefly, the audio signals are applied to an input circuit including a microphone 2 and an amplifier 4, and are reproduced on a real-time basis, but at a lower frequency, in an output circuit including a speaker 6, e.g. a loud speaker or earphones. Thus, many of the high frequency tones in the originally-inputted audio signal, which might not have been heard by the person because of his limited-frequency audibility, will be reduced in frequency such that the person can hear them. Since this reduction in frequency of the originally-inputted audio signals occurs on a real-time basis, the person using the device hears the sound at substantially the same time as the sound is received by the microphone 2.
More particularly, the sounds are converted to electrical analog signals by microphone 2, are amplified by amplifier 4, and are then applied to two analog shift registers ASR1 and ASR2, connected in parallel to the input circuit. As mentioned above, these analog shift registers are known devices each capable of storing, under the control of loading clock pulses, the analog signals in the form of a plurality of analog samples, and of outputting them under the control of unloading clock pulses. As one example, there may be used for each of the analog shift registers ASR1, ASR2, two Phillips TDA 1022 units, each having 512 stages, thereby providing a total of 1024 stages for each of the shift registers.
The loading and unloading clock pulses controlling the analog shift registers are provided by an oscillator 8 and a frequency divider 10. Oscillator 8 outputs high frequency pulses via line 12, and frequency divider 10 outputs lower frequency pulses via line 14, being, in the described arrangement, one-half of the higher frequency pulses supplied via line 12. Frequency divider 10 further supplies another series of pulses at a rate 1/4096 the rate of the high-frequency pulses supplied by oscillator 8; these pulses, acting as switching pulses, are supplied via line 16 to a cyclically-operable analog switch 18 for controlling same in the manner to be described more particularly below.
Analog switch 18 cyclically controls three switching devices, namely switching device 20 controlling a first flip-flop FF1, switching device 22 controlling a second flip-flop FF2, and switching device 24 selectively connecting the output of the two analog shift registers ASR1 and ASR2 to the output circuit including speaker 6.
Flip-flop FF1 supplies the loading clock pulses and the unloading clock pulses to analog shift register ASR1. Thus, when it is connected by switching device 20 to line 12 supplying the high-frequency pulses from oscillator 8, it produces clock pulses of the same high frequency and supplies them to the loading gate of analog shift register ASR1 to load that register from the input circuit, including a microphone 2 and amplifier 4, at the high-frequency rate of the pulses on line 12. On the other hand, when flip-flop FF1 is connected by switching device 20 to line 14, it produces and supplies lower-frequency clock pulses to analog shift register ASR1 to unload that register at the rate corresponding to the lower-frequency of the pulses on line 14.
Flip-flop FF2 controlled by switching device 22 supplies the clock pulses to analog shift register ASR2 in a similar manner. That is, when flip-flop FF2 is connected by its switching device 22 to line 12, it supplies high-frequency clock pulses to load analog shift register ASR2 from the input circuit at the high-frequency rate corresponding to the frequency of the pulses on line 12; and when the flip-flop is connected to line 14, it unloads analog shift register ASR2 at the rate corresponding to the lower-frequency of the pulses on line 14.
Switching device 24, controlled by analog switch 18, selectively connects the output end of the two shift registers ASR1, ASR2 to the output circuit including speaker 6, such that only the register being unloaded is connected to the output circuit. The rate of operation of switching device 24 corresponds to the frequency of the pulses on line 16, which as indicated above, is much lower than the frequency of the pulses on either of lines 12 or 14.
The output circuit includes, in addition to speaker 6, also a low-pass filter 26 and an amplifier 28. The low-pass filter 26 receives the analog samples outputted by the analog shift register ASR1 or ASR2 connected to the output circuit via switching device 24, and from these analog samples it reconstructs the original analog signal but at a different frequency, determined by the frequency relationship of the two clock pulses supplied by the flip-flops FF1, FF2. Amplifier 28 amplifies this reconstructed analog signal before applying same to speaker 6 which converts same to sound. The outputted sound will thus correspond to and will occur substantially simultaneously with, the sound inputted into the microphone 2, but would be at a lower frequency, one-half in this example.
The operation of the system of FIG. 1 is illustrated in the following Table 1:
TABLE 1______________________________________Phase 1 Phase 2______________________________________High-frequency High-frequencyloading ASR1 loading ASR2Low-frequency Low-frequencyunloading ASR2 unloading ASR1______________________________________
The two phases are controlled by the cyclically-operable analog switch 18, which in turn is controlled by the switching pulses supplied to it by line 16. Thus, during Phase 1 (wherein the switching devices 20,22 and 24 controlled by analog switch 18 are in the positions illustrated in FIG. 1), it will be seen that flip-flop FF1 is connected to the high-frequency pulse line 12, so that it supplies high-frequency loading clock pulses to its analog shift register ASR1 loading same with analog samples of the amplified audio signals from microphone 2. During this same Phase 1, flip-flop FF2 is connected to the low-frequency pulse line 14, so that it supplies low-frequency unloading clock pulses to its analog shift register ASR2, unloading same at the low-frequency rate. Also during this Phase 1, switching device 24 connects the output end of analog shift register ASR2 to the output circuit, so that the analog samples unloaded from register ASR2 are fed to the output circuit.
The system remains in Phase 1 for a time interval sufficient to completely unload the analog shift register ASR2. Since this register is being unloaded at a slower (one-half) rate than the rate at which analog shift register ASR1 is being loaded, it will be appreciated that analog shift register ASR1 will overflow and will lose one-half the information loaded into it during this time interval. That is, one-half of the information will not be transmitted to the low-pass filter 26 in the output circuit. However the low-pass filter substantially reconstructs the original analog signal, so that the original sound inputted into the microphone 2 is outputted from speaker 6 but a lower frequency, namely at one-half the frequency of the inputted sound signal.
It will be appreciated that during Phase 2, the analog switch 18 switches the connections 20, 22, 24 so that the analog shift register ASR1 is now unloaded at the low-frequency of the pulses on line 14, and analog shift register ASR2 is now loaded at the high-frequency of the pulses on line 12. During this Phase 2, switching device 24 connects the output of analog shift register ASR2 to the low-pass filter 26 which filter reconstructs the original audio signal before it is amplified in amplifier 28 and outputted via speaker 6.
Phase 2 continues with the switching device 24 in the above-described position until analog shift register ASR2 completely unloads, at which time the analog switch 18 then actuates all the switching devices 20, 22, and 24 back to the positions illustrated in FIG. 1 to institute a new Phase 1.
FIG. 2 illustrates a specific implementation of the system of FIG. 1, with corresponding elements and components correspondingly numbered. Thus, oscillator 8 supplies the high-frequency pulses via line 12 to a cyclically-operable analog switch 18 which may be an integrated circuit (IC3) analog multiplexer (e.g., Motorola MC14053B) including the equivalent of the switching devices 20, 22 and 24. The outputs 20' and 22', corresponding to the outputs of the switching devices 20 and 22 in FIG. 1, are applied to the two flip-flop FF1 and FF2 both included in an integrated circuit (IC4), such as Motorola MC14013B. Flip-flip FF1 clocks analog shift register ASR1, which is in the form of an integrated circuit (IC5), e.g., Motorola TDA 1022; and flip-flop FF2 clocks analog shift register ASR2, which is the same type of integrated circuit (IC6). Each of these latter integrated circuits has 512 stages, and it is preferable to include, for each analog shift register, two such units so as to provide an analog shift register of 1024 stages for each.
Line 24' from the analog switch 18 represents the output end of the switching device 24 in FIG. 1 and feeds the analog time samples being unloaded from the analog shift register in the respective phase, to the combined low-pass filter and amplifier unit 26-28. The filter reconstructs the original audio signal, but at a reduced frequency (one-half in the above-described example), before it is amplified and converted back to sound in speaker 6.
For purposes of example, the high-frequency clock pulses may be at 15 kHz, the low-frequency clock pulses may be at 7.5 kHz, and the switching pulses may be at 7.32 Hz, whereby the registers are unloaded every 136 milleseconds.
Whereas FIGS. 1 and 2 illustrate the system applied to the real-time division of the frequency of an analog signal, the invention could also be applied to the real-time multiplication of the frequency of an analog signal. This is illustrated in FIG. 3. In the example of FIG. 3, the frequency is doubled, and therefore the system includes three phases of operation; three analog shift registers identified as ASR11, ASR12, and ASR13; and three flip-flops identified as FF11, FF12 and FF13. The analog signal is inputted to the three analog shift registers in parallel via microphone 102 and amplifier 104, and is eventually outputted via speaker 106. The high-frequency pulses are supplied by an oscillator 108 via line 112, and the low-frequency pulses are supplied by a frequency divider 110 via line 114. Frequency divider 110 also supplies the phase-switching pulses via line 116 to the cyclically operable analog switch 118.
Analog switch 118 controls a clock-control switching device and an output switching device for each of the analog shift registers.
Thus, with respect to shift register ASR11, analog switch 118 controls switching device SW1 to connect either the high-frequency pulses from line 112 or the low-frequency pulses from line 114 to its flip-flop FF11, which flip-flop controls the rate of loading and unloading of its respective analog shift register ASR11. In addition, analog switch 118 controls switching device SW2 at the output end of analog shift register ASR11, connecting same to the low-pass filter 126 in the output circuit whenever the analog shift register is being unloaded.
The same applies with respect to the other two analog shift registers ASR12 and ASR13. Thus, switching device SW3 controls flip-flop FF12 which determines the rate of loading and unloading of its analog shift register ASR12, and also controls switching device SW4 which connects the latter register to the output circuit when the register is being unloaded. Similarly, switching device SW5 controls its flip-flop FF13 which in turn controls the rate of loading and unloading of analog shift register ASR13, and also controls switching device SW6 which connects the output end of the latter register to the output circuit when the latter register is being unloaded.
As in the above-described embodiment of FIGS. 1 and 2, the output circuit includes, in addition to the low-pass filter 126, also an amplifier 128 and a speaker 106, e.g. ear-phones for individual use, or a loud speaker.
The operation of the system illustrated in FIG. 3 will be better understood by reference to the following Table 2.
TABLE 2______________________________________Phase 1 Phase 2 Phase 3______________________________________High-frequency Low-frequency Low-frequencyunloading ASR11 loading ASR11 loading ASR11SW1:a SW2:a SW1:b SW2:b SW1:b SW2:bLow-frequency High-frequency Low-frequencyloading ASR12 unloading ASR12 loading ASR12SW3:b SW4:b SW3:a SW4:a SW3:b SW4:bLow-frequency Low-frequency High-frequencyloading ASR13 loading ASR13 unloading ASR13SW5:b SW6:b SW5:b SW6:b SW5:a SW6:a______________________________________
It will thus be seen that during Phase 1, contacts "a" of both switching devices SW1 and SW2 are operative. Accordingly, analog shift register ASR11 will be unloaded into the output circuit at the high-frequency rate of the signals supplied from oscillator 108 via line 112.
During the same Phase 1, contacts "b" of both switching devices SW3 and SW4 are operative, and therefore analog shift register ASR12 will be loaded at the low-frequency rate of the signals supplied from the divider circuit 110 via line 114. Similarly during this Phase 1, contacts "b" of switching devices SW4 and SW5 will also be operative, so that analog shift register ASR13 will also be loaded at the low-frequency rate of the signals on line 114.
At the end of Phase 1, analog switch 118 actuates the above switching devices to initiate Phase 2, wherein contacts "b" of switching devices SW1 and SW2 are operative; contacts "a" of switching devices SW3 and SW4 are operative; and contacts "b" of switching devices SW5 and SW6 are operative. Accordingly, analog shift register ASR13 will be loaded at the low-frequency rate; analog shift register 12 will be unloaded at the high-frequency rate; and analog shift register ASR13 will be loaded at the low-frequency rate.
At the end of Phase 2, analog switch 118 actuates the switching devices to initiate Phase 3, wherein contacts "b" of switching devices SW1 and SW2 are operative, thereby causing analog shift register ASR11 to load at the low-frequency rate; contacts "b" of switching devices SW3 and SW4 are operative, thereby causing analog shift register ASR12 to be loaded at the low-frequency rate; and contacts "a" of switching devices SW5 and SW6 are operative, thereby causing analog shift register ASR13 to be unloaded at the high-frequency rate.
It will thus be seen that during each phase of the cycle, one of the analog shift registers is unloaded at the high-frequency rate, while the remaining two shift registers are loaded at the low-frequency rate. Thus, the sound originally inputted into the microphone 102 will be reproduced by the speaker 106 in a real-time manner, but at double the frequency of the original sound.
One application for the real-time frequency-multiplying circuit of FIG. 3 is in a secrecy communication system, wherein messages are transmitted at a high-frequency so as to be unintelligible by receivers unless equipped with a corresponding frequency-dividing circuit as illustrated for example in FIG. 1. In such a system, however, it would be desirable to multiply the frequency by a factor greater than "2". This can be done by connecting a plurality of the frequency-doublers of FIG. 3 and frequency-dividers of FIG. 1 in tandem.
FIG. 4 illustrates one such arrangement. Thus, as shown in FIG. 4, there are four frequency-multiplier stages FM1-FM4, which thereby multiply the audio signals originally inputted into the microphone 202 by a factor of "16", the output being transmitted via antenna 250. The signals are received by receiver antenna 252, and are preferably passed through a high-pass filter 254 before being fed to the frequency-reducing circuit including four frequency-divider stages FD1-FD4, each corresponding to the system illustrated in FIGS. 1 or 2, before the signal is amplified in amplifier 228 and converted to sound by speaker 206.
Thus, a receiver not equipped with the frequency-reducing circuit described above will receive the original sound but at a frequency multiplied by a factor of "16", which will make the sound substantially unintelligible, if audible at all. However, a receiver equipped with the frequency-reducing circuit described above will automatically reduce the received signal by the factor of "16," and will therefore reproduce, in an audible and intelligible manner, the original sound and at the same frequency as the original sound.
While the invention has been described with respect to two preferred embodiments, it will be appreciated that many other variations, modifications and applications of the invention may be made.
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An analog signal processing system is described for changing the frequency of analog signals in a real-time manner. The system includes at least two analog shift registers, (specifically, three analog shift registers), an input circuit connecting the input end of all the registers in parallel, an output circuit selectively connectable to the output ends of the registers, a high frequency clock pulse source, a lower frequency clock pulse source, and cyclically operable switching means effective to load from the input circuit at least one analog shift register at the rate corresponding to the frequency of one of the clock pulses, while unloading at least one other register into the output circuit at the rate corresponding to the frequency of the other clock pulses.
Two applications are described, for purposes of example. One application is as a hearing aid device to reduce the frequency of audio signals in a real-time manner for a person having a limited-frequency audibility. The other application is a communication device for the real-time transmission and reception of audio signals rendering them unintelligible except by receivers equipped with a processing system for reducing the frequency of the received signals.
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CROSS REFERENCE TO RELATED APPLICATION
This application is a divisional patent application of its copending parent patent application, Ser. No. 074,157 filed Sept. 10, 1979 now U.S. Pat. No. 4,342,886.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to an improved combination of a control device and an electrical switch unit carried thereby and to a method of making the same.
This invention also relates to an improved electrical switch unit for such a device or the like and to improved parts for such an electrical switch unit or the like as well as to improved methods of making such switch units and parts therefor.
2. Prior Art Statement
It is known to provide a combination of a burner valve control device and an electrical switch unit carried thereby to be operated by movable actuator means controlled by the selector means of the device whereby turning the selector means to a certain position thereof will cause the electrical switch to operate electrical ignition means to ignite fuel being controlled by the burner valve control device.
In one such prior known arrangement, the electrical switch unit is fastened by conventional fastening means to the rear of the housing of the burner valve control device and an elongated bell-crank-like member is pivotally carried by the housing of the control device and extends from the selector means thereof to the electrical switch to operate the same.
It is also known to provide an electrical switch construction having a housing means carrying a pair of switch blades therein and respectively having contact portions for engaging each other, the housing means carrying an actuating member for engaging one of the switch blades to thereby move the contact portion thereof out of contact with the contact portion of the other of the switch blades.
It is also known to provide a switch blade construction for an electrical switch construction wherein the switch blade construction has a flexible end switching portion and an opposed rigid terminal portion, the terminal portion comprising a separate rigid member secured to a flexible switch blade that forms the flexible end switching portion.
SUMMARY OF THE INVENTION
It is a feature of this invention to provide an improved combination of a burner valve control device and an electrical switch unit carried thereby.
In particular, it was found according to the teachings of this invention, that a unique snap-fit arrangement can be provided for the burner valve control device and the electrical switch unit so that the electrical switch unit can be snap-fitted to the device so as to be detachably secured thereto.
Accordingly, one embodiment of this invention provides a combination of a burner valve control device and an electrical switch unit carried by the device and being operated by movable actuator means controlled by the selector means of the device, the switch unit having snap-fit means snap-fitted to the device when the entire switch unit is moved in a direction substantially transverse to the axis of rotation of a control shaft of the selector means to detachably secure the switch unit to the device.
It is another feature of this invention to provide an improved actuator means for actuating the switch means of the switch unit that is carried by the burner valve control device and is operated by the selector means thereof.
In particular, it is found according to the teachings of this invention that a bell-crank-like lever can be pivotally mounted to the switch unit to be carried thereby and still provide means whereby the selector means of the burner valve control device can operate the same.
Accordingly, an embodiment of this invention provides a combination of a burner valve control device and an electrical switch unit carried by the device and having the switch means thereof operated by movable actuator means that is, in turn, operated by the selector means of the device, the movable actuator means comprising substantially anchor-shaped lever pivotally mounted to the switch unit to be carried thereby and having an arcute actuator arm means engageable with the selector means of the device and the switch means of the switch unit. The lever has the arcuate actuator arm means provided with opposed end means for respectively being engageable with the selector means of the device and the switch means of the switch unit, the lever having a shank portion extending substantially radially from the arm means substantially medially of the end means thereof and having an outer free end pivotally mounted to the switch unit.
It is another feature of this invention to provide an improved electrical switch construction.
In particular, it was found according to the teachings of this invention that the switch blades of a switch construction can be uniquely arranged so that one switch blade is mounted intermediate another switch blade and an actuator means operates the outboard switch blade in a unique manner.
For example, an embodiment of this invention provides an electrical switch construction having a housing means carrying a pair of switch blades therein and respectively having contact portions for engaging each other, the housing means carrying an actuator member for engaging and moving one of the switch blades to thereby move the contact portion thereof out of contact with the contact portion of the other of the switch blades. The other switch blade is disposed intermediate the one switch blade and the actuator member and the one switch blade has an end looped therefrom and disposed intermediate the other switch blade and the actuator member to be engaged by the actuator member.
It is another feature of this invention to provide an improved switch blade for an electrical switch construction.
In particular, it was found according to the teachings of this invention that a switch blade can comprise a one-piece member and have a rigid terminal portion and a flexible switching portion.
For example, one embodiment of this invention provides a switch blade for an electrical switch construction wherein the switch blade has a flexible end switching portion and an opposed rigid terminal portion, the switch blade comprising a one-piece member having the terminal portion formed from a part of the one-piece member folded upon itself.
Accordingly, it is an object of this invention to provide an improved combination of a burner valve control device and an electrical switch unit carried by the device, the combination of this invention having one or more of the novel features of this invention as set forth above or hereinafter shown or described.
Another object of this invention is to provide a method of making a combination of a burner valve control device and an electrical switch unit carried by the device, the method of this invention having one or more of the novel features of this invention as set forth above or hereinafter shown or described.
Another object of this invention is to provide an improved electrical switch construction, the electrical switch construction of this invention having one or more of the novel features of this invention as set forth above or hereinafter shown or described.
Another object of this invention is to provide a method of making an electrical switch construction, the method of this invention having one or more of the novel features of this invention as set forth above or hereinafter shown or described.
Another object of this invention is to provide an improved switch blade for an electrical switch construction, the switch blade of this invention having one or more of the novel features of this invention as set forth above or hereinafter shown or described.
Another object of this invention is to provide a method of making a switch blade for an electrical switch construction, the method of this invention having one or more of the novel features of this invention as set forth above or hereinafter shown or described.
Other objects, uses and advantages of this invention are apparent from a reading of this description which proceeds with reference to the accompanying drawings forming a part thereof and wherein:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an exploded perspective view illustrating the improved combination of this invention that comprises a burner valve control device and an electrical switch unit carried by the device.
FIG. 2 is a front view of the assembled burner valve control device and the electrical switch unit of FIG. 1.
FIG. 3 is an enlarged view similar to FIG. 2 with various parts broken away and shown in cross section.
FIG. 4 is a cross-sectional view taken on line 4--4 of FIG. 3.
FIG. 5 is a fragmentary cross-sectional view taken in the direction of the arrows 5--5 of FIG. 3.
FIG. 6 is a partially broken away side view of the combination illustrated in FIG. 3 and is taken in the direction of the arrows 6--6 of FIG. 3.
FIG. 7 is a fragmentary view similar to FIG. 3 and illustrates the switch construction in an open condition thereof.
FIG. 8 is an enlarged top view of one of the switch blades of the switch construction of this invention.
FIG. 9 is a side view of the switch blade of FIG. 8.
FIG. 10 is a top view of the other switch blade of switch construction of this invention.
FIG. 11 is a side view of the switch blade illustrated in FIG. 10.
FIG. 12 is a fragmentary view of the switch blade of FIG. 11 as taken in the direction of the arrows 12--12 of FIG. 11.
FIG. 13 is an enlarged fragmentary cross-sectional view taken on the line 13--13 of FIG. 12.
FIG. 14 is a view similar to FIG. 2 and illustrates another embodiment of the combination of this invention that comprises the burner valve control device and an electrical switch unit carried thereby.
FIG. 15 is a view similar to FIG. 3 without the control device and illustrates another embodiment of the electrical switch construction of this invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
While the various features of this invention are hereinafter described and illustrated as being particularly adapted to provide an electrical switching arrangement for a burner valve control device for a top burner of a cooking apparatus or the like, it is to be understood that the various features of this invention can be utilized singly or in any combination thereof to provide devices for other structures as desired.
Therefore, this invention is not to be limited to only the embodiments illustrated in the drawings, because the drawings are merely utilized to illustrate one of the wide variety of uses of this invention.
Referring now to FIGS. 1 and 2, the improved combination of this invention is generally indicated by the reference numeral 20 and comprises a burner valve control device 21 carrying an electrical switch unit 22 in a manner hereinafter set forth so that when a selector means 23 of the device 21 is turned to a certain position or positions thereof, the switch means that is generally indicated by the reference numeral 24 in FIG. 3 will be disposed in the closed condition illustrated in FIG. 3 to operate suitable electrical ignition means (not shown) to ignite fuel issuing from a top burner (not shown) of a cooking apparatus and being fed thereto by the control device 21 out of an outlet means 25 thereof in a manner well known in the art.
The switch means 24 of the switch unit 22 comprises a pair of switch blades 26 and 27 respectively having contact portions 28 and 29 adapted to be disposed in contact with each other when an actuator means 30 of the switch unit 22 is disposed in the position illustrated in FIG. 3 so as to electrically interconnect together terminal portions 31 and 32 of the switch blades 26 and 27 to operate the aforementioned electrical ignition means. However, when the actuator means 30 is moved to the position illustrated in FIG. 7, it can be seen that the contact portion 29 of the switch blade 27 is moved out of contact with the contact portion 28 of the switch blade 26 so as to break electrical connection between the terminal ends 31 and 32 to thereby place the electrical ignition means in an "off" condition thereof.
The electrical switch unit 22 comprises a housing means 33 having a chamber 34 therein which receives the switch blades 26 and 27 and is adapted to be closed by a cover plate 35.
The cover plate 35 has a cup-shaped part 36 formed integrally therewith and being adapted to pivotally mount the actuator member 30 thereto so as to be carried by the switch unit 22.
In particular, the actuator member 30 comprises substantially anchor-shaped lever having a pivot pin-like part 37 which is pivotally mounted to the housing means 33 and the cup-shaped retainer 36 in the manner illustrated in FIG. 4 so that an arcuate arm 38 of the lever 30 can have its opposed ends 39 and 40 respectively disposed in engagement with a cam surface 41 of the selector means 23 and a looped free end 42 of the switch blade 27, the end 40 of the actuator 30 comprising an offset portion 40' extending into the chamber 34 of the housing means 33 to engage the end 42 of the switch blade 27 as illustrated. Thus, it can be seen that the lever has a shank portion extending substantially radially from the arm 38 medially of its opposed ends 39 and 40, the shank portion having its free outer end 37 pivotally mounted to the switch unit 22.
The housing means 33 of the switch unit 22 has a cylindrical stop member 43 disposed intermediate the switch blades 26 and 27 to be engaged thereby in a manner now to be described.
The terminal portions 31 and 32 of the switch blades 26 and 27 are respectively mounted in suitable slot means 44' and 45' of the housing means 22 so that the left hand portions 46 and 47 of the switch blades 26 and 27 in FIG. 3 are disposed in cantilevered fashion and respectively have a natural bias toward the stop 43 with the bias of the switch blade 27 being greater than the bias of the switch blade 26.
In this manner, when the actuator 30 is disposed in the position illustrated in FIG. 3, the natural bias of the switch blade 27 moves the flexible portion 47 thereof upwardly against the stop 43 so that the contact portion 29 thereof makes contact with the contact portion 28 of the switch blade 26 and moves the switch blade 26 therewith upwardly out of contact with the stop 43 as illustrated in FIG. 3. However, when the actuator member 30 is moved from the position illustrated in FIG. 3 to the position illustrated in FIG. 7 in the manner hereinafter set forth, the arm end 40 of the actuator 30 moves the flexible portion 47 of the switch blade 27 downwardly and the flexible portion 46 of the switch blade 26 follows such movement until the flexible portion 46 is against the stop 43 as illustrated in FIG. 7 so that further downward movement of the switch blade 27 moves its contact portion 29 out of contact with the contact portion 28.
The selector means 23 of the device 21 includes a control knob shaft 48 carrying a drive plate 49 having an outer peripheral portion 50 rotatably mounted in an annular chamber 51 of the housing means 52 of the device 21 so that rotational movement of the shaft 48 will be imparted by a drive tang 53 of the drive plate 49 to a valve member 54 rotatably mounted in the housing means 52 and being adapted to interconnect a fuel source inlet 55 to the outlet 25 in a manner well known in the art.
The outer periphery 50 of the drive plate 49 defines the cam surface 41 previously described which has a low area 56 as illustrated in FIG. 3 and a high area 57 as illustrated in FIG. 7 so that when the low area 56 is disposed adjacent the end 39 of the actuator 30, the natural bias of the switch blade 27 causes the switch means 24 to assume the condition illustrated in FIG. 3 wherein the contact portions 29 and 28 are disposed in contact with each other and the switch blade 27 is against the stop 43. However, when the high portion 57 of the drive plate 49 is moved against the end 39 of the actuator member 30 in the manner illustrated in FIG. 7, the actuator member 30 is cammed in a counterclockwise direction in the drawings so that the end 40 thereof moves the switch blade 27 downwardly as previously described to open the contact portion 29 thereof from the contact portion 28 as the downward movement of the switch blade 26 is stopped by the stop means 43 as illustrated in FIG. 7.
Thus, it can be seen that by properly shaping the cam surface 41 of the drive plate 49, the switch means 24 can be opened and closed as certain sections of the cam surface 41 are disposed adjacent the end 39 of the actuator 30 to operate the electrical ignition means for the burner device 21 as desired.
As previously stated, it is a feature of this invention to provide an improved means for detachably securing the switch unit 22 to the burner valve control device 21.
In particular, the housing means 33 of the switch unit 22 is provided with a pair of upstanding legs 58 which are respectively adapted to be snap-fitted in a pair of slot means 59 defined by the housing means 52 of the burner valve control device 21.
Each slot means 59 of the burner valve control device 21 defines a pair of opposed edge means 60 and each leg 58 of the switch unit 22 is bifurcated to define two parallel sections 61 each having a notch 62 facing outwardly so that the notches 62 of the two sections 61 of each leg 58 are adapted to respectively snap-fittingly receive the adjacent edges 60 of the housing means 52 of the device 21 therein when the legs 58 are snap-fitted upwardly into the slots 59 in the manner illustrated in FIG. 3.
In this manner, the switch unit 22 is adapted to be snap-fitted to the housing 52 of the device 21 so as to be carried thereby and can be readily detached therefrom by merely squeezing together the leg sections 61 of each leg 58 so that the same can be pulled out of the slot means 59 in a simple manner.
In order to properly locate the switch unit 22 to the device 21 when the same is being snap-fitted thereto, the housing means 52 of the device 21 can be provided with locating recess means 63 adapted to receive a locating abutment 64 of the switch unit 22 therein in the manner illustrated in FIGS. 3 and 4 when the legs 58 of the switch unit 22 are snap-fitted in the slots 59 in the manner previously set forth.
As previously stated, another feature of this invention is to provide an improved switch blade for an electrical switch construction.
Therefore, it can be seen that the switch blades 26 and 27 for the electrical switch units 22 of this invention are adapted to each be uniquely formed from a one-piece member to define not only the resilient portions 46 and 47 thereof, but also the rigid terminal portions 44 and 45 thereof.
In particular, reference is made to FIGS. 8 and 9 wherein in the switch blade 26 is shown in enlarged form and comprises a one-piece metallic member of considerable length looped and folded upon its self to define stacked layers 65, 66, 67 and 68 respectively defined by a plurality of folds 69, 70 and 71 so that the layers 65-68 define the rigid terminal portion 44 thereof.
The stacked layers 65-68 of the switch blade 26 can be secured together in any suitable manner. For example, the stacked layers 65-68 can be riveted together by suitable rivets (not shown) being inserted in suitable openings 26' formed through the stacked layers 65-68.
As illustrated in FIG. 8, the stacked layers 65-68 are adapted to be provided with a plurality of outwardly directed tangs 72, 73, 74 and 75 to provide suitable corners for positively locating and securing the switch blade 26 in the housing means 22 in a manner well known in the art, the layer 65 of the one-piece switch blade member extending beyond the tangs 73 and 74 and tapering substantially from the medial portions 76 and 77 thereof to define the flexible portion 46 of the switch blade 26.
The contact portion 28 of the switch blade 26 is defined by arcuately bending the free end 78 thereof as illustrated in FIG. 9.
As illustrated in FIGS. 10 and 11, the other switch blade 27 is also formed from an elongated one-piece member folded upon itself to define a plurality of layers 79, 80, 81 and 82 defined by folded parts 83, 84 and 85 so that the layers 79-82 define the rigid terminal portion 45 of the blade 26 while the layer 82 extends beyond the rigid portion 45 to define the flexible portion 47 thereof having the loop 42 defined at the end 86 thereof, the stacked layers 79-82 being adapted to be secured together by suitable rivets (not shown) passing through the openings 27' in the stacked layers 79-82 if desired.
The terminal portion 45 of the blade 27 also has a plurality of outwardly directed tangs 87, 88, 89 and 90 for positively locating and securing the switch blade 27 in the housing means 22, the layer 82 tapering from the medial portions 91 and 92 of the tangs 88 and 89 to define the flexible portion 47 thereof as illustrated.
The contact portion 29 of the switch blade 27 is defined by an embossed flattened substantially rectangular portion 93 thereof as illustrated in FIGS. 11, 12 and 13.
In this manner, the flattened embossed portion 93 of the switch blade 27 provides a wiping surface against which the curved contact portion 28 of the switch blade 26 will engage so that as the switch blades 27 and 26 are moved relative to each other, a sliding wiping action takes place between the curved contact portion 28 of the blade 26 and the flattened embossed portion 93 of the switch blade 27 in order to break any welds that may exist therebetween.
While the switch blades 26 and 27 have each been illustrated as being formed from an elongated length thereof folded upon itself in a longitudinal direction to define the rigid terminal portion 44 or 45 thereof, it is to be understood that the switch blade 26 or 27 could be formed by having a one-piece member folded laterally from one or both sides thereof to define a stacked layer thereof rather than from the end thereof in order to form the rigid terminal portion thereof if desired.
From the above, it can be seen that the combination of the control device 21 and switch unit 22 of this invention can be formed by the methods of this invention to operate in a manner now to be described.
After the switch unit 22 has been snap-fitted to the burner valve control device 21 by having the bifurcated legs 58 thereof snap-fitted through the slots 59 so that the locating means 64 of the housing means 33 of the switch unit 22 is disposed in the recess means 63 of the device 21, it can be seen that the arm 38 has its end 39 disposed against the cam surface 41 of the drive plate 49 while its other end 40 is disposed against the looped end 42 of the switch blade 27.
As long as a low portion 56 of the cam surface 41 is disposed against the end 39 of the arm 38 of the actuator member 30, the natural bias of the flexible portion 47 of the switch blade 27 overcomes the natural bias of the flexible portion 46 of the switch blade 26 to move the switch blade 26 upwardly therewith until the switch blade 27 is disposed against the stop 43 and the end 42 is disposed against the end 40 of the actuator 30. In this manner, the contact portions 28 and 29 of the switch blades 26 and 27 are disposed in contact with each other so that the electrical ignition system for the burner associated with the device 21 is rendered operative through the closed switch means 22.
However, when the operator rotates the selector shaft 48 of selector means 23 to another position thereof wherein a high side 57 of the cam surface 41 bears against the end 39 of the member 30, the member 30 is moved in a counterclockwise direction as illustrated in FIG. 7 to move the switch blade 27 out of contact with the contact portion 28 of the switch blade 26 as the switch blade 26 engages against the stop 43 to prevent further movement downwardly with the switch blade 27 so that the switch means 24 is disposed in the open position illustrated in FIG. 7 as long as the selector means 23 for the device 21 is disposed in a position that presents a high side 57 of the cam surface 41 to the actuator 30.
Therefore, it can be seen that the combination of the control device 20 and the electrical switch unit 22 of this invention is operated by the uniquely arranged anchor-shaped member 30 that is pivotally carried by the switch unit 22. Also, it can be seen that the switch blades 26 and 27 are uniquely arranged within the switch unit 22 to have the looped end 42 of the outboard blade 27 acted upon by the actuator 30 even though the actuator 30 is disposed outboard of the intermediate switch blade 26.
While the switch unit 22 has been illustrated and described as having bifurcated legs 58, it is to be understood that the switch unit 22 could have other means for providing the snap-fit arrangement with the device 21.
For example, reference is made to FIG. 14 wherein another combination of this invention is generally indicated by the reference numeral 20A and parts thereof similar to the combination previously described are indicated by like reference numerals followed by the reference letter "A".
As illustrated in FIG. 14, the switch unit 22A has a pair of legs 58A extending upwardly therefrom and each has a notch 60A adapted to snap-fit over a ledge 94 of the housing means 52A of the device 21A to snap-fit the unit 22A to the device 21A.
Also, while the actuator 30 of this invention has been described as having a fixed distance between the opposed ends 39 and 40 thereof, it is to be understood that the anchor-doped member 30 of this invention can be made adjustable to provide for variations in the assembly of the units 22 to the devices 21.
For example, reference is made to FIG. 15 wherein another switch unit of this invention is generally indicated by the reference numeral 22B and parts thereof similar to the switch unit 22 previously described are indicated by like reference numerals followed by the reference letter "B".
As illustrated in FIG. 15, the only difference between the switch 22B and the switch unit 22 previously described is the actuator member 30B which is provided with a slot 95 between the opposed ends 39B and 40B thereof. The natural resiliency of the member 30B is to hold the opposed sides 96 and 97 of the slot 95 closely adjacent to each other so that the distance between the ends 39B and 40B will be at a minimum. However, the side 96 of slot 95 is provided with a plurality of teeth 98 in rack-like form which are adapted to cooperate with teeth 99 on a rotatable pinion 100 disposed in the slot 95, the side 97 of the slot 95 being smooth and converging toward the side 96 as the sides 96 and 97 approach the open end of the slot 95.
In this manner, a person can insert a screwdriver or the like in a slot 101 of the pinion 100 and rotate the same within the slot 95 so that rotation of the pinion 100 causes the pinion 100 to either climb upwardly along the teeth 98 or downwardly depending upon the rotation of the pinion 100.
Thus, as the pinion 100 is rotated in a counterclockwise direction in FIG. 15, the pinion 100 will move upwardly along the track 98 and by engaging against the smooth surface 97 of the slot 95 will cause the slot 95 to widen and thereby position the ends 39B and 40B further apart the more the pinion 100 is driven upwardly in the slot 95. Conversely, as the pinion 100 is rotated in a clockwise direction in FIG. 15, the pinion 100 will move downwardly in the slot 95 and thereby permit the opposed ends 39B and 40B to move closer to each other.
Accordingly, it can be seen that by providing the adjustable anchor-shaped member 30B, adjustment can be made between selector means of the device 21 and the switch means 24B in the switch unit 22B to compensate for any manufacturing differences therebetween so that the actuator 30B will properly operate the switch means 24B when the selector means has the particular cam surface thereof against the end 39B of the actuator 30B.
From the above, it can be seen that this invention not only provides an improved combination of a burner valve control device and an electrical switch therefor, but also this invention provides an improved electrical switch unit and parts therefor. In addition, this invention provides a method of making such an improved combination as well as methods of making an electrical switch construction and parts therefor.
While the forms and methods of this invention now preferred have been illustrated and described as required by the Patent Statute, it is to be understood that other forms and method steps can be utilized and still fall within the scope of the appended claims.
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A combination of a burner valve control device and an electrical switch unit carried by the device and being operated by a movable actuator controlled by the selector of the device, the selector having a control shaft rotatable about an axis thereof. The switch unit has a snap-fit arrangement snap-fitted to the device when the entire switch unit is moved in a direction substantially transverse to the axis of the control shaft to detachably secure the switch unit to the device.
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This is a division of application Ser. No. 042,812 filed Apr. 27, 1987, now U.S. Pat. No. 4,729,980.
BACKGROUND OF THE INVENTION
The present invention is drawn to an improved catalyst for use in the hydrodemetallization and hydroconversion of heavy hydrocarbon feedstocks and method of making same and, more particularly, an improved catalyst having two distinct phases supported on a refractory support wherein the first phase effectively stores metals removed from the feedstock and the second phase exhibits superior catalytic activity for hydrogenation when processing heavy hydrocarbon feedstocks.
Heretofore, operations such as hydrotreatment of heavy hydrocarbons are performed in the presence of catalysts comprising elements of Group VIII and Group VIB supported on a refractory oxide support. These types of catalysts suffer from a number of disadvantages. For example, during the hydrotreatment of heavy feedstocks the life of most of the conventional catalyst is shortened by a fast deactivation. The first cause for the deactivation is the deposition of coke on the catalyst. Coke deposits can be avoided by improving the hydrogenation activity of the catalyst. The second cause for the deactivation results from metal deposits on the catalyst.
Most of the patents related to improved demetallization catalysts deal with special designs of the catalyst pore size distribution. It has been found in the prior art that a catalyst having a macropore structure can generally accumulate higher amounts of metals. In order to achieve this macropore structure several approaches have been considered in the prior art. One of these is to vary the form and size of the catalyst particles and the surface area and the porosity of the catalyst support. The following patents are examples: U.S. Pat. No. 4,014,821, U.S. Pat. No. 4,082,695, U.S. Pat. No. 4,102,822, U.S. Pat. No. 4,297,242, U.S. Pat. No. 4,328,127, U.S. Pat. No. 4,351,717, U.S. Pat. No. 4,411,771, U.S. Pat. No. 4,414,141. The optimum pore structure appears to be well known in the previous art. Having established the optimum pore structure, the next step would be to optimize the chemical formulation and composition of the catalyst.
Patents which deal with variations in the chemical composition and formulation are as follows: U.S. Pat. No. 3,898,155, U.S. Pat. No. 3,931,052, U.S. Pat. No. 3,985,684, U.S. Pat. No. 4,344,867 and G.B. Pat. No. 2,032,795. The first three patents consider the inclusion of a third element besides the Group VIB and Group VIII elements in the catalyst. U.S. Pat. No. 4,344,867 is concerned with a chemical treatment of a catalyst support. The G.B. Pat. No. 2,032,795 patent eliminates the Group VIB element from the composition and introduces a method of core impregnation for the preparation of the catalyst. All of these patents however are based on the fact that larger pores can accumulate higher amounts of metals. Thus, while some improvement in demetallization may be accomplished employing these catalyst, the increase in demetallization is generally accompanied by a loss in hydrogenation activity.
Accordingly, it is the principal object of the present invention to provide a catalyst and method for making same which exhibits good simultaneous demetallization and hydrogenation activity when processing heavy hydrocarbon feeds.
It is a particular object of the present invention to provide a catalyst and method for making same as set forth above having two distinct metal phases deposited on a refractory support.
It is a further object of the present invention to provide a catalyst and method for making same as set forth above wherein the first phase is a demetallization phase and the second phase is a hydrogenation phase.
It is a still further object of the present invention to provide a catalyst and method for making same as set forth wherein the weight ratio of the phases as measured by mossbauer spectrum are controlled.
Further objects and advantages of the present invention will appear hereinbelow.
SUMMARY OF THE INVENTION
In accordance with the present invention the foregoing objects and advantages are readily obtained.
The present invention is drawn to an improved catalyst for use in the hydrodemetallization and hydroconversion of heavy hydrocarbon feedstocks and method of making same and, more particularly, an improved catalyst having two distinct phases supported on a refractory support wherein the first phase effectively stores metals removed from the feedstock and the second phase exhibits superior catalytic activity for hydrogenation when processing heavy hydrocarbon feedstocks. The catalyst of the present invention comprises a refractory support having a first demetallization phase and a second hydrogenation phase supported thereon, the first demetallization phase being selected from the group consisting of iron oxide, iron sulphide and mixtures thereof and the second phase being selected from the group consisting of iron-Group VIB metal oxides, iron-Group VIB sulphides and mixtures thereof wherein the weight ratio of the first phase to the second phase as measured by mossbauer spectrum is from about 0.1 to 8.0, the iron is present in an amount of from about 4 to 20 wt.% and the Group VIB metal is present in an amount of from about 0.1 to 8 wt.% wherein the atomic ratio of iron to Group VIB metal is from about 0.3 to 20. In accordance with a preferred embodiment of the present invention, the refractory support is selected from the group consisting of alumina, silica, titania and mixtures thereof and has the following pore size distribution:
≦90 Å diameter: between 0-10% pore volume
90-300 Å diameter: between 20-85% pore volume
300-500 Å diameter: between 5-20% pore volume
≧500 Å diameter: between 0-10% pore volume.
The method for preparing the catalyst comprises providing a refractory support structure, first impregnating the refractory support structure with an acid iron nitrate solution so as to obtain a composition of from about 4 to 20 wt.% iron on the final catalyst, filtering, drying and calcining the impregnated support, second impregnating the filtered, dried and calcined iron impregnated support with a solution containing a Group VIB metallic component so as to obtain a composition of from about 0.1 to 8 wt.% Group VIB metallic component on the final catalyst, and filtering, drying and calcining the impregnated support. The process for treating heavy hydrocarbon feedstocks with the catalyst of the present invention comprises contacting the feedstock with the catalyst of the present invention at a temperature of from about 150° to 500° C., at a pressure of from about 30 to 250 atmospheres and LHSV of from about 0.1 to 25 h -1 in a reactor.
The catalyst of the present invention is capable of storing metals removed from the heavy hydrocarbon feedstock in the demetallization phase supported on the refractory support. The iron oxide and/or iron sulphide phase can store large amounts of metals without metal accumulating into the pores thereby avoiding structural change and correspondingly a decrease in activity. The catalyst offers superior simultaneous demetallization and hydrogenation over catalysts heretofore known.
DETAILED DESCRIPTION
Effective simultaneous demetallization and hydrogenation of a heavy hydrocarbon feedstock can be accomplished when employing the catalyst of the present invention. The term "demetallization" as used herein refers to the elimination of at least 70% of the metals in the heavy feedstock as effected by passing the feedstock through a reaction zone containing the catalyst of the present invention.
The catalyst of the present invention comprises a refractory support having a first demetallization phase and a second hydrogenation phase supported thereon, the first demetallization phase being selected from the group consisting of iron oxide, iron sulphide and mixtures thereof and the second phase being selected from the group consisting of iron-Group VIB metal oxides, iron-Group VIB sulphides and mixtures thereof wherein the weight ratio of the first phase to the second phase as measured by mossbauer spectrum is from about 0.1 to 8.0, the iron is present in an amount of from about 4 to 20 wt.% and the Group VIB metal is present in an amount of from about 0.1 to 8 wt.% wherein the atomic ratio of iron to Group VIB metal is from about 0.3 to 20. In accordance with a preferred embodiment of the present invention the iron and Group VIB metal are present in an amount of from about 4 to 20 wt.% and 1.0 to 5.0 wt.%, respectively, wherein the atomic ratio of iron to Group VIB metal is from about 0.6 to 5.0. The first phase in the preferred embodiment contains from about 30 to 85 wt.%, and preferably 30 to 70 wt.% of the total iron content of the final catalyst and, when in the form of an iron sulphide, should have a crystalline structure selected from the group consisting to the cubic system, the hexagonal system, the monoclinic system and mixtures thereof. The crystalline structure of the first phase is important only when the phase is iron sulphide. If the phase is iron oxide, crystalline structure is immaterial. This is because iron oxide is a precursor which would yield iron sulfide under reaction conditions. The second phase preferably contains a crystalline structure of the cubic system and the atomic ratio of iron to Group VIB metal is from about 0.8 to 3.0. The preferred refractory support is selected from the group consisting of alumina, silica, titania and mixtures thereof and has the following pore size distribution:
≦90 Å diameter: between 0-10% pore volume
90-300 Å diameter: between 20-85% pore volume
300-500 Å diameter: between 5-20% pore volume
≧500 Å diameter: between 0-10% pore volume.
In order to obtain the two phases on the refractory support in the final catalyst it is critical that the support first be impregnated with iron and thereafter impregnated with the Group VIB metal. The method of the present invention comprises providing a refractory support structure, first impregnating the refractory support structure with an acid iron nitrate solution so as to obtain a composition of from about 4 to 20 wt.% iron on the final catalyst, filtering, drying and calcining the impregnated support, second impregnating the filtered, dried and calcined iron impregnated support with a solution containing a Group VIB metallic component so as to obtain a composition of from about 0.5 to 8 wt.% Group VIB metallic component on the final catalyst, and filtering, drying and calcining the impregnated support. The foregoing process results in two phases being deposited on the refractory surface, the first phase being iron oxide and the second phase being iron-Group VIB oxides. If desired, the resultant catalyst can be presulphided so as to form iron sulphide and iron-Group VIB sulphide by presulphiding is at a temperature of about 250° to 450° C., a pressure of about 1 and 150 atmospheres in an H 2 /H 2 S atmosphere containing between 5 to 15 wt.% H 2 S.
The first demetallization phase has been characterized by its x-ray diffraction pattern and its mossbauer spectrum. The x-ray diffraction pattern of the first phase is used for the determination of the crystal structure of the precursor iron oxide or the iron sulphide which is present in the presulphided catalysts. It has been found that only crystals of iron sulfides of the hexagonal, cubic or monoclinic system can store the metals removed from the oil without loss in stability because they present cation vacancies which can lodge the metal cations from the crude oil.
The mossbauer spectrum allows to quantify the proportion or ratio between the phases. The area of the mossbauer spectrum of any compound is proportional to its concentration. Thus, the integration of each of the spectrum of different compounds present in a sample would yield their weight percentage. The first phase is characterized by a six line spectrum while the second phase is characterized by a doublet spectrum. The mossbauer parameters of these two phases fall in the ranges specified as follows:
______________________________________ Magnetic Isomer Quadripole Field Shift SplittingPhase H (gauss) IS (mms.sup.-1) QS (mms.sup.-1)______________________________________First(Oxide) 350-600 0.0-0.5 0.0-0.5(Sulphide) 150-350 0.0-0.6 0.0-0.6Second(Oxide) 0 0.0-2.0 0.0-3.0(Sulphide) 0 0.0-2.0 0.0-3.0______________________________________
Examination of spent catalysts by mossbauer spectroscopy reveals that the catalyst acts to store the metal contaminants from the oil. The relative proportion between the two phases serve to control the activity, stability (life) and the selectivity of the catalyst.
The pore size distribution of the catalyst is important only in the sense of permitting a good diffusion of the reactant molecules throughout the catalyst and is preferably as follows:
≦90 Å diameter: between 0-10% pore volume
90-300 Å diameter: between 20-85% pore volume
300-500 Å diameter: between 5-20% pore volume
≧500 Å diameter: between 0-10% pore volume.
A catalyst of the present invention is useful in hydrotreatment operations involving heavy feedstocks. It possesses a good catalytic activity for hydrodemetallization and hydroconversion reactions. The heavy feedstocks to be handled in these operations might be vacuum residues, deasphalted crudes and also heavy vacuum gas oils.
In cases where a presulphided catalyst is desirable, it should be presulphided with a light sulphur containing feed at temperatures in the range of 250° to 450° C. at pressures between 1 and 150 atmospheres of H 2 . The H 2 /H 2 S ratio is critical in order to keep the first phase/second phase ratio within the recommended limits. A mixture containing between 5 to 15% of H 2 S is adequate. The H 2 S is provided for the sulphur compound in the presulphiding feed. Suitable sulphur compounds are H 2 S, CS 2 , mercapthans, and/or any organic sulphur compound.
The shape and/or the size of the catalyst is not limiting. It can be used in any shape or size, in a fixed bed reactor, stirred tank and/or slurry. The process operation consists of contacting the feed with the catalyst in the presence of hydrogen under the following conditions: temperature of between 150° to 500° C., preferably 250° to 480° C., pressure of between 30 to 250 atms., preferably 50 to 150 atms., and LHSV (h -1 ) of between 0.1 to 25, preferably 0.1 to 15.
The following examples are given in order to more fully describe, but not to limit, the invention.
EXAMPLE 1
A catalyst was prepared by consecutive impregnation of pellets of γ-Al 2 O 3 support. Iron was firstly impregnated using an acid iron nitrate solution containing 1.12 mol. per liter solution of iron. A solution volume of twice the pore volume of the support was employed. The catalyst was then carefully washed, filtered dried and calcined. Molybdenum was impregnated secondly, using an ammonium heptamolybdate solution containing 0.20 mol. per liter solution of molybdenum. A procedure similar to that employed with iron was then followed. The final catalyst had the following physical and chemical properties:
Physical Properties
Surface Area: 145 m 2 g -1
Pore Volume: 0.81 cc g -1
Pore Size Distribution: % pore volume
Diameter (Å):
<90: 8.5
90-300: 62.2
300-500: 23.7
>500: 5.6
Chemical Properties
Fe: 6 %w
Mo: 2 %w
The catalyst was grounded to a 15 μm average presulphided at 350° C., 1.2 atmosphere of pressure using a mixture of H 2 /H 2 S at a ratio of 1:10. The sulphided catalyst was analyzed by x-ray diffraction and mossbauer spectroscopy. The results indicated that two iron compounds were present, namely:
Hexagonal Fe 7 S 8 : 40% of total iron
Cubic Fe x Mo y S z : 60% of total iron
The mossbauer parameters of these two compounds were measured as follows:
______________________________________ Magnetic Isomer Quadripole Field Shift Splitting H (gauss) IS (mms.sup.-1) QS (mms.sup.-1)______________________________________Fe.sub.7 S.sub.8 226-302 0.6 0.0-0.25(6 lines)Fe.sub.x Mo.sub.y S.sub.z 0 0.3-1.5 0.8-2.5(2 lines)______________________________________
The catalytic activity was evaluated in a 3.5 liter autoclave under the following conditions:
Temperature: 450° C.
H 2 pressure: 1900 psi
H 2 flow rate: 16 l min -1
Duration: 5 h
Catalyst: 8 %w
Feed: 1000 g
The feed was a heavy vacuum residue Zuata feedstock having the following properties:
API gravity: 2.2°
Sulphur content: 4.9%
Vanadium content: 750 ppm
Asphaltenes: 25 %w
Conradson Carbon: 27 %w
The results of the catalytic activity test are as follows:
HDM: 98
HDS: 70
Asphaltene Conversion: 95
Conradson Carbon Conversion: 94
API Gravity Variation: 25.2
As can be seen from the foregoing, the catalyst of the present invention is extremely effective in the demetallization and hydrogenation of heavy feedstocks.
EXAMPLE 2
The initial activity of the catalyst of Example 1 in pellet form, and a conventional commercial catalyst of CoMo-type having a similar pore size distribution and a Co content of 2.5 %w and Mo content of 12.3 %w were evaluated in a Carberry reactor using the following conditions:
Temperature: 400° C.
H 2 pressure: 1500 psi
Catalyst: 6%
Feed: 600 g
The feedstock was a deasphalted Morichal having the following properties:
API gravity: 16.7°
Vanadium content: 150 ppm
Sulphur content: 2.4% w
Asphaltenes: 2.4% w
Conradson Carbon: 5.1
The two catalysts were subjected to three consecutive runs, (with intermediate xylene washing) and evaluated under the same conditions, in order to determine the final activity of a partially deactivated catalyst. The results are summarized in Table I.
TABLE I______________________________________CATALYTIC ACTIVITY OF NOVELCATALYST AND CONVENTIONAL CATALYST FeMoAl CoMoAlActivity Initial Final Initial Final______________________________________HDM 70 65 90 10HDS 35 15 98 35HDC.sub.540 + 75 100 65 34Asphaltene Conversion 78 78 92 66Conradson Carbon 50 61 55 47Conversion______________________________________
As can be seen from Table I the life of the catalyst of the present invention is superior to known catalysts.
EXAMPLE 3
A test was carried out similar to Example 2 above but using three additional feedstocks which consist of the same DAO diluted in light gas oil at different proportions, so as to give the following vanadium contents (ppm):
Feed 1: 150
Feed 2: 100
Feed 3: 30
The vanadium removal (HDM) and the conversion of the 540° C. + fraction (HDC 540 +) were evaluated, the results were as follows:
______________________________________ Feedstocks 1 2 3 FeMo CoMo FeMo CoMo FeMo CoMo______________________________________HDM Initial 75 92 78 94 80 95Final 73 15 76 45 78 86HDC Initial 85 70 88 75 92 80Final 98 55 100 68 100 72______________________________________
Again the superiority of the catalyst of the present invention is demonstrated, when metal concentration in the feed is high.
EXAMPLE 4
A series of catalysts were prepared as in Example 1 to yield different first phase/second phase and Fe/Mo ratios. The catalysts were not presulphided. The chemical composition of these catalysts is shown in Table II.
TABLE II______________________________________ First Phase/Catalyst Fe/Mo Second Phase First Phase Second Phase______________________________________1 35 10 α-Fe.sub.2 O.sub.3 α-FeMoO.sub.42 8.0 4.5 α-Fe.sub.2 O.sub.3 α-FeMoO.sub.43 3.9 2.5 γ-Fe.sub.2 O.sub.3 α-FeMoO.sub.44 2.8 1.4 γ-Fe.sub.2 O.sub.3 α-FeMoO.sub.45 2.0 0.5 γ-Fe.sub.2 O.sub.3 α-FeMoO.sub.46 0.9 0.0 -- α-FeMoO.sub.47 0.7 0.05 α-Fe.sub.2 O.sub.3 α-FeMoO.sub.48 0.4 0.08 α-Fe.sub.2 O.sub.3 α-FeMoO.sub.49 0.3 0.15 α-Fe.sub.2 O.sub.3 β-FeMoO.sub.410 0 No Iron______________________________________
The catalytic activity and stability was evaluated in the same manner as in Example 2, however, the catalysts were used in the oxide form (as identified in Table II). The results are reported in Table III.
TABLE III______________________________________ Conradson HDC Asphaltene CarbonHDM HDS 540.sup.+ Conversion ConversionCatalyst I F I F I F I F I F______________________________________1 10 8 2 2 15 13 10 8 7 82 54 52 18 17 56 54 68 55 25 243 62 58 19 20 65 67 73 62 32 294 68 64 20 19 70 72 75 73 48 465 71 65 24 15 75 100 78 78 50 606 92 38 43 12 88 25 95 42 82 287 90 55 40 16 84 52 92 50 75 368 86 70 39 20 83 61 88 78 70 429 84 73 39 20 80 68 86 65 68 4910 86 25 33 12 80 20 88 18 70 20______________________________________ I -- Initial F = Final
Table III demonstrates the criticality of iron-Group VIB metal ratio and the first phase/second phase ratio on hydrodemetallization and hydroconversion.
EXAMPLE 5
Catalyst No. 5 of Example 4 was presulphided at different H 2 S/H 2 ratios. The iron sulphide of the first phase exhibited the following crystal structures.
______________________________________No. H.sub.2 S/H.sub.2 Crystal System First Phase______________________________________5-1 1:5 Cubic Fe.sub.1-x S5-2 1:10 Monoclinic Fe.sub.y S.sub.85-3 1:15 Hexagonal Fe.sub.y S.sub.85-4 1:20 Hexagonal FeS5-5 1:30 Tetragonal FeS______________________________________
The initial catalytic activity was measured in the same manner as in Example 2. The results were as follows:
______________________________________HDM HDS HDC.sub.540+______________________________________5-1 72 43 485-2 75 28 625-3 85 22 395-4 50 10 205-5 35 8 15______________________________________
The foregoing demonstrates the criticality of the crystal structure of the first phase on activity.
This invention may be embodied in other forms or carried out in other ways without departing from the spirit or essential characteristics thereof. The present embodiment is therefore to be considered as in all respects illustrative and not restrictive, the scope of the invention being indicated by the appended claims, and all changes which come within the meaning and range of equivalency are intended to be embraced therein.
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An improved catalyst for use in the hydrodemetallization and hydroconversion of heavy hydrocarbon feedstocks and method of making same and, more particularly, an improved catalyst having two distinct phases supported on a refractory support wherein the first phase effectively stores metals removed from the feedstock and the second phase exhibits superior catalytic acitivity for hydrogenation when processing heavy hydrocarbon feedstocks.
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TECHNICAL FIELD OF THE INVENTION
The present invention relates to a rotating asynchronous converter.
The present invention also relates to a generator device.
BACKGROUND OF THE INVENTION
In a number of situations exchange of power must be performed between AC networks with different or at least not synchronous frequencies. The most frequent cases are the following:
1. Connection of not synchronous three phase networks with equal rating frequencies, e.g. between eastern and western Europe. 2. Connection of three phase networks with different frequencies, most usually 50 Hz/60 Hz (e.g. Japan, Latin America). 3. Connection of a three phase network and a low frequency, one/two phase network for railway supply, in Europe 50 Hz/16.2/3 Hz, in USA 60 Hz/25 Hz. 4. The use of rotating asynchronous converters as a series compensation in long distance AC transmission.
Today, the connection is performed with the aid of power electronics and DC intermediate link. In the above mentioned cases 2 and 3 the connection can further be performed with the aid of matrix converters. In case of synchronous, but different frequencies in the above mentioned cases 2 and 3 the connection can further be performed with the aid of rotating converters comprising mechanically connected synchronous machines.
In the article, “Investigation and use of asynchronized machines in power systems”, Electric Technology USSR, No. 4, pp. 90-99, 1985, by N. I. Blotskii, there is disclosed an asynchronized machine used for interconnection of power systems, or their parts, which have different rated frequencies, or the same rated frequencies, but differing in the degree of accuracy with which it must be maintained. The structure of the asynchronized machine is disclosed in FIG. 1 . The asynchronized machine includes an electric machine 1 which is a machine with a conventional three-phase stator and either a non-salient-pole symmetrical rotor or a salient-pole or non-salient-pole electrically asymmetrical rotor, the phase leads being connected to slip rings; an exciter 2 which is a cycloconverter or reversing controlled rectifier, the cycloconverter supply 3 or 4 , a regulator 5 forming the control law required for the rotor ring voltages and the main machine rotor angle and speed 6 , voltage 7 and current 9 sensors of the stator and rotor.
In the article, “Performance Characteristics of a Wide Range Induction type Frequency Converter”, IEEMA Journal, Vol. 125, No. 9, pp. 21-34, Sep. 1995, by G. A. Ghoneem, there is disclosed an induction-type frequency converter as a variable frequency source for speed control drives of induction motors. In FIG. 2 there is disclosed a schematic diagram of the induction-type frequency converter. The induction-type frequency converter consists of two mechanically and electrically coupled wound rotor induction machines A, B. The stator windings of one of them (A) are connected to 3-phase supply at line frequency (Vi, Fi), while the stator windings of the other machine (B) represent the variable frequency output (Vo, Fo). The rotor windings 10 , 12 of the two machines are connected together with special arrangement. The converter is driven by a variable speed primemover 14 , a DC motor can be used.
Static converters have drawbacks such as relatively low efficiency (ca 95%) owing to the losses in the semiconductors, harmonics which have to be compensated with the aid of filters. The use of DC intermediate links leads to the use of special converter transformers with very complex design. The fillers are leading to a great need of space for the total assembly. Conventional rotating converters are not designed for high voltages, so a transformer is needed at each side for the connection to the AC network. The efficiency then becomes comparable to or even lower than the efficiency of a static converter.
SUMMARY OF THE INVENTION
The object of the invention is to solve the above mentioned problems and to provide a rotating asynchronous converter for connection of AC networks with equal or different frequencies. This object is achieved by providing a rotating asynchronous converter.
Accordingly, the converter comprises a first stator connected to a first AC network with a first frequency f 1 , and a second stator connected to a second AC network with a second frequency f 2 . The converter also comprises a rotor means which rotates in dependence of the first and second frequencies f 1 , f 2 . At least one of the stators each comprise at least one winding, wherein each winding comprises at least one current-carrying conductor, and each winding comprises an insulation system, which comprises on the one hand at least two semiconducting layers, wherein each layer constitutes substantially an equipotential surface, and on the other hand between them is arranged a solid insulation.
According to another embodiment of the converter, it comprises a first stator connected to a first AC network with a first frequency f 1 , and a second stator connected to a second AC network with a second frequency f 2 . The converter also comprises a rotor means which rotates in dependence of said fist and second frequencies f 1 , f 2 . The stators each comprise at least one winding, wherein each winding comprises a cable comprising at least one current-carrying conductor, each conductor comprises a number of strands, around said conductor is arranged an inner semiconducting layer, around said inner semiconducting layer is arranged an insulating layer of solid insulation, and around said insulating layer is arranged an outer semi-conductor layer.
According to another embodiment of the converter, it comprises a first stator connected to a first AC network with a first frequency f 1 , and a second stator connected to a second AC network with a second frequency f 2 . The converter also comprises a rotor means which rotates in dependence of said first and second frequencies f 1 , f 2 . The stators each comprises at least one winding, wherein each winding comprises at least one correct-carrying conductor. Each winding also comprises an insulation system, which in respect of its thermal and electrical properties permits a voltage level in said rotating asynchronous converter exceeding 36 kV.
A very important advantage of the present invention is that it is possible to achieve a connection of two not synchronous networks without the further use of transformers or any other equipment. Another advantage is the high efficiency, which is expected to be 99%.
By designing the insulation system, which suitably is solid, so that it in thermal and electrical view is dimensioned for voltages exceeding 36 kV, the system can be connected to high voltage power networks without the use of intermediate step-down-transformers, whereby is achieved the above referenced advantages. Such a system is preferably, but not necessarily, designed in such a way that it comprises the features of the rotating asynchronous converter.
Another object of the invention is to solve the above mentioned problems and to provide a generator device with variable rotational speed. This object is achieved by providing a generator device.
Accordingly, the generator device comprises a stator connected to an AC network with a frequency f 2 , a first cylindrical rotor connected to a turbine, which rotates with a frequency f 1 . The generator device also comprises a rotor means which rotates in dependence of the frequencies f 1 , f 2 . The stator and the first cylindrical rotor each comprises at least one winding, wherein each winding comprises at least one current-carrying conductor, and each winding comprises an insulation system, which comprises on the one hand at least two semiconducting layers, wherein each layer constitutes substantially an equipotential surface, and on the other hand between them is arranged a solid insulation.
According to another embodiment of the generator device, it comprises a stator connected to an AC network with a frequency f 2 , and a first cylindrical rotor connected to a turbine, which rotates with a frequency f 1 . The generator device also comprises a rotor means which rotates in dependence of the frequencies f 1 , f 2 . The stator and the first cylindrical rotor each comprises at least one winding, wherein each winding comprises a cable comprising at least one current-carrying conductor, each conductor comprises a number of strands, around said conductor is arranged an inner semiconducting layer, around said inner semiconducting layer is arranged an insulating layer of solid insulation, and around said insulating layer is arranged an outer semiconducting layer.
The above mentioned and other preferable embodiments of the present invention are specified in the dependent claims.
In a certain aspect of the present invention it relates to the use of the invented asynchronous converter in specific applications such as those specified in claims 38 - 41 , in which applications the advantages of the invented device are particularly prominent.
Embodiments of the invention will now be described with a reference to the accompanying drawings, in which:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a schematic diagram of an asynchronized machine used for interconnection of power system according to the state of the art;
FIG. 2 shows a schematic diagram of an induction-type frequency converter as a variable frequency source according to the state of the art;
FIG. 3 shows the parts included in the current modified standard cable;
FIG. 4 shows a first embodiment of a rotating asynchronous converter according to the present invention;
FIG. 5 shows a second embodiment of the rotating asynchronous converter according to the present invention;
FIG. 6 shows a first embodiment of a generator device according to the present invention; and
FIG. 7 shows a second embodiment of the generator device according to the present invention.
DETAILED DESCRIPTION OF EMBODIMENTS
A preferred embodiment of the improved cable is shown in FIG. 3 . The cable 20 is described in the figure as comprising a current-carrying conductor 22 which comprises both transposed non-insulated 22 A and insulated 22 B strands. There is an extruded inner semiconducting casing 24 which, in turn, is surrounded by an extruded insulation layer 26 . This layer is surrounded by an external semiconducting layer 28 . The cable used as a winding in the preferred embodiment has no metal shield and no external sheath.
Preferably, at least two of these layers, and most preferably all of them, has equal thermal expansion coefficients. Hereby is achieved the crucial advantage that in case of thermal motion in the winding, one avoids defects, cracks or the like.
FIG. 4 shows a first embodiment of a rotating asynchronous converter 30 according to the present invention. The rotating asynchronous converter 30 is used for connection of AC networks with equal or different frequencies. The converter 30 comprises a first stator 32 connected to a first AC network (not disclosed) with a first frequency f 1 , and a second stator 34 connected to a second AC network (not disclosed) with a second frequency f 2 . In the disclosed embodiment the stators 32 , 34 are three phase stators 32 , 34 comprising three windings each, wherein each winding comprises at least one current-carrying conductor, and each winding comprises an insulation system, which comprises on the one hand at least two semiconducting layers, wherein each layer constitutes substantially an equipotential surface, and on the other hand between them is arranged a solid insulation. The windings can also be formed of a cable of the type disclosed in FIG. 3 . The converter 30 also comprises a rotor means 36 which rotates in dependence of the first and second frequencies f 1 , f 2 . In the disclosed embodiment the rotor means 36 comprises two electrically and mechanically connected three phase rotors 36 1 , 36 2 , which are concentrically arranged in respect of said stators 32 , 34 . The converter 30 also comprises an auxiliary device 38 connected to said rotors 36 1 , 36 2 for starting up of the rotors 36 1 , 36 2 to a suitable rotation speed before connection of said converter 30 to said AC networks. Each rotor 36 1 , 36 2 comprises a low voltage winding (not disclosed). When the first stator 32 is connected to a three phase AC network with the frequency f 1 and the second stator 34 is connected to a three phase AC network with the frequency f 2 , the rotors 36 1 , 36 2 will rotate with the frequency (f 1 −f 2 )/2 and the stator current has the frequency (f 1 +f 2 )/2. The efficiency with such a converter will be very high (˜99%) for small frequency differences due to the fact that all power is transmitted as in a transformer. Assuming f 1 <f 2 , a proportion
f 1 - f 2 f 2
of the power is transmitted mechanically and the remainder
f 1 f 2
of the power is transmitted by transformer action. Mechanical power is only consumed to maintain the rotation.
In FIG. 5 there is disclosed a second embodiment of the rotating asynchronous converter 40 according to the present invention. The rotating asynchronous converter 40 is also used for connection of AC networks with equal or different frequencies. The converter 40 comprises a first stator 42 connected to a first AC network (not disclosed) with a first frequency f 1 , and a second stator 44 connected to a second AC network (not disclosed) with a second frequency f 2 . In the disclosed embodiment the stators 42 , 44 are three phase stators 42 , 44 comprising three windings each, wherein each winding can be of the type described in connection to FIG. 4 . The converter 40 also comprises a rotor means 46 which rotates in dependence of the first and second frequencies f 1 , f 2 . In the disclosed embodiment the rotor means 46 comprises only one rotor 46 concentrically arranged in respect of said stators 42 , 44 . Said rotor 46 also comprises a first loop of wire 48 and a second loop of wire 50 , wherein said loops of wire 48 , 50 are connected to each other and are arranged opposite each other on said rotor 46 . The loops of wire 48 , 50 are also separated by two sectors 52 1 , 52 2 , wherein each sector 52 1 , 52 2 has an angular width of α. The converter 40 also comprises an auxiliary device (not disclosed) connected to said rotor 46 for starting up of the rotor 46 to a suitable rotational speed before connection of said converter 40 to said AC networks. To compensate for the frequency difference Δf, the rotor 46 only needs to rotate with the frequency
f R = π - α π · Δ f 4 ,
wherein Δf=|f 1 −f 2 |. For α=π/4 this means
f R = 3 Δ f 16 ,
a very low rotational frequency. The main advantages with this embodiment are the low rotational frequency and the use of only one rotor.
In FIG. 6 there is disclosed a first embodiment of a generator device 60 with variable rotational speed according to the present invention. The generator device 60 comprises a stator 62 connected to an AC network (not disclosed) with a frequency f 2 and a first cylindrical rotor 64 connected to a turbine 66 , which rotates with a frequency f 1 . The generator device 60 comprises also a rotor means 68 which rotates in dependence of the frequencies f 1 , f 2 . The stator 62 and said first cylindrical rotor 64 each comprises at least one winding (not disclosed). Each winding comprises at least one current-carrying conductor, and each winding comprises an insulation system, which comprises on the one hand at least two semiconducting layers, wherein each layer constitutes substantially an equipotential surface, and on the other hand between them is arranged a solid insulation. Each winding can in another embodiment also comprise a cable of the type disclosed in FIG. 3 . The rotor means 68 comprises two electrically and mechanically connected rotors 68 1 , 68 2 , which rotors 68 1 , 68 2 are hollow and arranged concentrically around said stator 62 and said cylindrical rotor 64 . The stator 62 in the disclosed embodiment has a cylindrical shape. The rotors 68 1 , 68 2 each comprises a low voltage winding (not disclosed) and they are rotating with the frequency (f 1 −f 2 )/2 when said generator device is in operation. The frequency of the rotor current will be (f 1 +f 2 )/2 when the generator device 60 is in operation. This generator device 60 is now disconnected from the power frequency and can be operated with the frequency as an optimizeable parameter. This generator device 60 will also give a better efficiency and power matching than a conventional generator.
In FIG. 7 there is disclosed a second embodiment of the generator device 70 according to the present invention. The generator device 70 comprises a stator 72 connected to an AC network (not disclosed) with a frequency f 2 and a first cylindrical rotor 74 connected to a turbine 76 , which rotates with a frequency f 1 . The generator device 70 also comprises a rotor means 78 which rotates in dependence of the frequencies f 1 , f 2 . The stator 72 and said first cylindrical rotor 74 each comprises at least one winding (not disclosed). The winding can be of the types which were mentioned in the description in connection to FIG. 6 . The rotor means 78 comprises a first rotor 78 1 and a second rotor 78 2 , which rotors 78 1 , 78 2 are electrically and mechanically connected to each other. The first rotor 78 1 is hollow and arranged concentrically around said first cylindrical rotor 74 and said second rotor 78 2 is cylindrical and surrounded by the stator 72 . The first and second rotors 78 1 , 78 2 of said rotor means 78 each comprises a low voltage winding and said rotors 78 1 , 78 2 are rotating with the frequency (f 1 −f 2 )/2 when said generator device 70 is in operation. The stator 72 is hollow and arranged around said second rotor 78 2 . This generator device 70 works in the same way and has the same advantages as the generator device 60 disclosed in FIG. 6 .
The disclosed embodiments only show connection of three phase networks, but the invention is also applicable for connection of a three phase network, wherein one stator has a one/two phase application. The invention can also be used for connection of a three phase network and a one/two phase network, wherein one stator having a three phase application is connected via a Scott-connection or another symmetrical connection to a one/two phase network. The invention is also applicable to more than two stators and rotor parts to connect more than two AC networks. The only condition is that only two not synchronous networks are connected.
The invention is not limited to the embodiments described in the foregoing. It will be obvious that many different modifications are possible within the scope of the following claims.
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A rotating asynchronous converter for connection of AC network with equal or different frequencies employs a first stator connected to a first AC network with a first frequency and a second stator connected to a second AC network with a second frequency, and a rotor which rotates in response to the first and second frequencies. The converter has at least one winding formed of a cable, including a conductor and a magnetically permeable, electric field confining insulating covering surrounding the conductor.
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BACKGROUND OF THE INVENTION
[0001] This invention relates to a method, device and apparatus for obtaining or controlling flow of fluid from more than one production zone, in particular, for achieving co-mingled flow of hydrocarbons in oil and gas wells.
[0002] After a wellbore has been drilled for an oil, gas or water well and the required depth has been reached, the well is fitted with production equipment. This is referred to as “well completion”. At this stage, a well will be cased and the necessary production tubing installed, incorporating various isolation seals to ensure integrity and safety of the well. Following installation of the production tubing, fluids can be produced from the various subsurface formations. Fluids may be recovered either through a single producing zone or a plurality of producing zones.
[0003] There are several known ways of producing from a plurality of producing zones, often referred to as multi-zone wells. The simplest option involves simultaneous production from all zones. FIG. 1 shows a sectional view of a known type of well completion having multiple production zones. Production tubing 18 is provided within a casing 10 . The annular space is isolated towards the lower end of the production tubing 18 by a production packer 14 .
[0004] First, second and third production zones 11 , 12 , 13 respectively, are formations containing hydrocarbons. The production tubing 18 and the casing 10 are perforated in the region of the zones 11 , 12 , 13 to allow hydrocarbons from each zone simultaneously to flow into the production tubing 18 . These hydrocarbons are prevented from flowing up the full length of the annulus by the production packer 14 . An annular space between each zone 11 , 12 , 13 and the production tubing 18 is isolated by zone isolation packers 16 . The apparatus of FIG. 1 allows simultaneous production from all zones 11 , 12 , 13 .
[0005] However due to the potentially differing flow rates and pressures in the different zones 11 - 13 , cross-flow may occur resulting in no production from one of the zones. The term “cross-flow” is used to describe a situation when fluids from one zone flow into a different zone rather than into production tubing and out of the well. Moreover the sediment within the fluid from the higher pressure zone can block any subsequent attempt at producing from the lower pressure zone.
[0006] One method to alleviate this problem, often used in the UK continental shelf, involves isolating each zone and then producing each zone sequentially. Once production is completed in one zone, an inflow control valve is closed and another zone is produced by opening a corresponding inflow control valve. The inflow control valve is often a sliding sleeve which may be operated by coiled tubing in the well. Sticking of such a sleeve in one position is a common failure associated with the sliding sleeve.
[0007] Another method of producing from multi-zone wells, commonly employed in Africa and the Far East, is the use of dual completion strings. This method entails running two sets of completion tubing into the well. One or more zones can then produce up one completion string, with the remaining production zones using the second completion string. Each set of tubing is separated from the other and the respective zones are separated using isolation packers. This method can be used in combination with the sequential production method described above, which includes sliding sleeves, to allow production from each zone in turn.
[0008] FIG. 2 shows a sectional view of a dual completion prior art well and is a known example of apparatus for producing from multiple zones. A casing 20 houses two sets of production tubing, 27 , 28 . Hydrocarbons from a first formation, zone 21 , can be produced using the production tubing 27 . Hydrocarbons from the first zone 21 can be prevented from entering an annular space between the casing 20 and production tubing 27 , 28 by a production packer 24 . The second and third zones 22 , 23 can be produced using the production tubing 28 and hydrocarbons from these zones 22 , 23 are prevented from mixing with hydrocarbons produced in the first zone 21 by a zonal isolation packer 26 .
[0009] The amount of equipment required and the high cost of installing an additional set of production tubing makes dual completion an expensive method of multi-zone production.
[0010] So-called “intelligent wells” are an alternative method of producing from multiple zones and these provide choke valves for each production zone. Intelligent wells are generally acceptable for zones with small pressure differences. However for zones with larger pressure differences, the pressure of the fluid from the higher pressure production zone remains relatively high after proceeding through the choke valve (which primarily controls its rate) and thus the same problems can occur with cross-flow between the production zones.
[0011] Other disadvantages associated with intelligent wells include the large expense required for installation, operation and maintenance. Additionally, the complicated valves and permanent gauge systems such as those used in intelligent wells can be unreliable. Repairing damaged choke valves is also conventionally difficult and expensive.
[0012] An object of the present invention is to alleviate any of the problems associated with the prior art.
BRIEF SUMMARY OF THE INVENTION
[0013] According to a first aspect of the present invention, there is provided a method of obtaining fluid from a first production zone and a second production zone, the method comprising:
[0014] (a) providing a first device to produce or control flow of fluid from the first production zone;
[0015] (b) in a well, providing a first well connector proximate to, and in fluid communication with, the first production zone;
[0016] (c) connecting the first device to the first well connector;
[0017] (d) providing a second device to produce or control flow of fluid from the second production zone;
[0018] (e) in the well, providing a second well connector proximate to, and in fluid communication with, the second production zone;
[0019] (f) connecting the second device to the second well connector;
[0020] (g) producing fluids from the first and second production zones through the well connectors and optionally through the devices.
[0021] The method is not limited to performing steps (a) to (g) in any particular order unless specifically stated. Preferably the well is a hydrocarbon producing well. Preferably at least one well connector is provided in the well during completion of the well. Typically the first and second devices are independently operated. Typically the well comprises casing with production tubing provided therein, and at least one well connector is provided in a side pocket provided in the production tubing, wherein when the device is connected to the well connector, the device is typically substantially located in the side pocket. Preferably each well connector is located in a side pocket. Preferably at least one device is releasably connected to at least one well connector. Preferably at least one device also connects to a power connector provided in the well, to supply the device with power. Preferably the device connected to a power connector is releasably connected to the power connector. The power connector may be in-built into the well connector so that a single connection connects the well connector and device with power and fluid. Alternatively separate connecting members may be provided for power and fluid connections. There may be more than two production zones. Typically each zone has a corresponding well connector and device. Optionally one zone, typically the one with the highest formation pressure, may not have a device. Preferably each zone is isolated from the other zones such that production fluid cannot pass from one zone to another. Preferably each device is releasably connected to each well connector.
[0022] Depending on the pressure of the first and second production zones, the first and second devices or pumps may, in use, independently reduce the pressure and/or flow rate of the fluid from the zones, or alternatively increase the pressure and/or flow rate from the zones.
[0023] According to a second aspect of the present invention, there is provided a device for producing or controlling fluid from a well, the device comprising a means to control or produce the flow of fluid from a zone, and a connector to releasably connect with a well connector, the well connector, in use, in fluid communication with the production zone.
[0024] Preferably the device according to the second aspect of the invention is used in the method according to the first aspect of the invention. The device typically comprises a valve. Alternatively the device may comprise a pump assembly. The device is typically adapted to connect with a power connector provided in the well connector. The device may be hydraulically powered. The device may be electrically powered. The device typically has a main longitudinal axis and is lowered within a well to form the connection with the well connector, the device is typically lowered in a direction generally parallel to said longitudinal axis, and a portion of the device which connects to the well connector may extend transversely with respect to said longitudinal axis. Typically the well connector provides for fluid communication between the device and the production zone. The valve may be used as a gas lift valve whereby gas is pumped down the annulus between casing and production tubing and exits through a side pocket into the well.
[0025] Pumps suitable for this application include suitably modified electric submersible pumps, progressive cavity pumps and jet pumps. For electric submersible pumps, a variable controller is typically provided which may be located at the surface or downhole. Preferably the device comprises a further connector adapted to connect with an electrical connector provided in the well. The pump is typically provided as a pump assembly comprising a plurality of parts, wherein the pumping action is provided in one part, the first connector in a second part and the second connector in a further part.
[0026] Where the device comprises a valve, typically the valve is a proportional valve, that is the proportion of fluid which can pass the valve is continuously variable from zero to a maximum value. Typically the device is shaped and adapted to be lowered and raised within a well by an elongate member, such as a wireline. The device is preferably shaped and adapted to be raised and lowered in the production tubing of a well.
[0027] Preferably the well connector comprises a check valve—thus it is not necessary to have a check valve in the device. This prevents back flow into the well connector when the valve or pump is removed.
[0028] According to a third aspect of the invention, there is provided a well apparatus comprising:
[0029] (a) a casing lining a well and a production tubing provided within the casing;
[0030] (b) a first well connector proximate to a first production zone, the first well connector, in use, in communication with the production zone;
[0031] (c) the well connector being connectable to a first device, said device comprising a means to control or produce a flow of fluid from the production zone;
[0032] (d) a second well connector proximate to a second production zone, the second well connector, in use, in communication with the second production zone;
[0033] (e) wherein the second well connector is connectable to a second device, said second device comprising a means to control or produce a flow of fluid from the production zone.
[0034] Preferably the device according to the third aspect of the invention is the device according to the second aspect of the invention. Preferably the apparatus comprises the device.
[0035] Preferably the apparatus according to the third aspect of the invention is used with the method according to the first aspect of the invention. Optionally at least one device comprises a valve. Alternatively at least one device comprises a pump. Preferably the well connector is provided in a side pocket of the production tubing between the casing and the production tubing. At least one well connector may be provided such that the device connects on the underside of the well connector. This can reduce the amount of debris which can fall into the well connector when it is not connected to the device. At least one well connector can comprise a valve operable in a non-axial direction with respect to the borehole. The valve may be operable in a substantially transverse direction.
[0036] The well apparatus may comprise a power and/or control line which extends down the well to the well connector which further comprises a power connector for connection to the device. Typically the control line is a hydraulic control line. A single control line may extend from the surface to the bottom of the well. An indexing pilot valve may then control each device. Each device can thus be controlled from a single line.
[0037] The line may extend on the outside of the production tubing and optionally connections are made through the tubing to the device located in the side pocket. The power connector may be an electrical connector. For example if an electric submersible pump is used or a stepping motor for a valve.
[0038] A single electrical power line may provide power for a plurality of devices. The single electrical power line may comprise a first earth core, a second core operating at positive voltage and a third core operating at negative voltage. The voltages are at least 500 dc or ac, preferably more than 750 dc or ac preferably around 1000 dc or ac.
[0039] The power connector may be a hydraulic connector. For example if a jet pump was used or a hydraulically activated valve.
[0040] The devices are preferably arranged in the well to allow full bore access to the well beneath the devices.
[0041] Typically the borehole comprises casing preferably also production tubing and therefore the well connector, in use, preferably connects the production zone to casing and more preferably to production tubing.
[0042] The production tubing preferably comprises a side pocket extending transversely into the well which is adapted to receive the device. Preferably the side pocket comprises the well connector. The power/control line(s) may extend directly to the device.
[0043] Optionally, the well connector can also comprise a check valve to prevent fluid backflow into the zone. According to a further aspect of the present invention, there is provided an apparatus for controlling or producing fluid from a well, the apparatus comprising a cartridge, the cartridge comprising a first device and a second device; the devices as herein described.
[0044] Preferably the cartridge is adapted to be removably connectable to the well. Thus the cartridge is adapted to be lowered and raised within a well by an elongate member, such as a wireline.
[0045] Preferably the apparatus according to the further aspect of the invention is performed using the method according to the first aspect of the invention.
[0046] The first and second devices can independently be a pump, a choke or other devices.
[0047] ‘Proximate’ as used herein preferably means within 20 m of perforations in the well casing or the open bore at the end of the well, preferably within 10 m, more preferably within 5 m.
[0048] Any feature of any aspect of any invention or embodiment described herein may be combined with any feature of any aspect of any other invention or embodiment described herein mutatis mutandis.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
[0049] Embodiments of the present invention will now be described, by way of example only, with reference to and as shown in the accompanying drawings.
[0050] FIG. 1 is a sectional view of a known well completion showing simultaneous production from several zones;
[0051] FIG. 2 is a sectional view of a known dual completion;
[0052] FIG. 3 is a sectional view of a portion of a well completion and apparatus according to one embodiment of the invention;
[0053] FIG. 4 is a sectional view of a cartridge according to another embodiment of the invention;
[0054] FIG. 5 is a sectional view of a well completion and the FIG. 4 cartridge;
[0055] FIG. 6 is a sectional view of a well completion in accordance with the present invention ready for producing fluids from multiple zones;
[0056] FIG. 7 is a sectional view of the well completion of FIG. 6 containing apparatus according to the invention;
[0057] FIG. 8 a is an enlarged view of a portion of the well completion of FIG. 6 ;
[0058] FIG. 8 b is an enlarged view of a portion of the well completion and apparatus of FIG. 7 showing a pump assembly according to the invention being run in;
[0059] FIG. 8 c is a further view of the FIG. 8 b well completion and apparatus with the pump assembly in a position ready to pump fluids to the surface;
[0060] FIG. 9 a is an enlarged view of a portion of the well of FIG. 6 containing an embodiment of a valve assembly according to the invention being run in;
[0061] FIG. 9 b is a further view of the FIG. 9 a well completion and valve assembly in a position ready to produce fluids to the surface;
[0062] FIG. 10 a is an enlarged view of a portion of the well completion of FIG. 6 containing a second embodiment of a valve assembly according to the invention being run in;
[0063] FIG. 10 b is a further view of the FIG. 10 a well completion and valve assembly in a position ready to produce fluids to the surface;
[0064] FIG. 11 a is a sectional view of a well completion in accordance with one embodiment of the present invention;
[0065] FIG. 11 b is a sectional view of the FIG. 11 a well completion with a pump being run in;
[0066] FIG. 11 c is a plan view of a the FIG. 11 a well completion;
[0067] FIG. 12 a is a sectional view of a well connector and first portion of a device according to a yet further aspect of the invention, in a mated position;
[0068] FIG. 12 b is a sectional view of the FIG. 12 a well connector and first portion of a device in a separated position;
[0069] FIG. 13 a is a sectional view of a first portion of a valve assembly according to a further aspect of the invention;
[0070] FIG. 13 b is a sectional view of a second portion of the valve assembly of FIG. 12 a;
[0071] FIG. 13 c is a sectional view of both portions of the valve assembly of FIGS. 12 a and 12 b , showing the valve in a closed position;
[0072] FIG. 13 d is a further sectional view of the valve assembly of FIGS. 12 a and 12 b , with the valve in a fully open position;
[0073] FIG. 13 e is a sectional view of a J-pin used in the valve assembly of FIGS. 12-12 d ; and
[0074] FIG. 14 is an illustrative view of a series of pump assemblies in accordance with one aspect of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0075] FIG. 3 shows a simplified sectional view of one embodiment of the apparatus according to one aspect of the invention in use. Zones 31 , 32 , 33 contain hydrocarbons and are in vertically spaced relation. A casing 30 is installed and set in the well after drilling through the zones 31 , 32 and 33 . Production tubing 38 is provided within the casing 30 . The resulting annular space between the casing 30 and the production tubing 38 is separated by packers 36 above each zone 31 , 32 , 33 .
[0076] A pump 39 is provided with an entry port (not shown) to allow inflow of hydrocarbons from zone 33 only. An arrow 29 indicates the direction of hydrocarbon flow. A wire wrapped screen 34 is provided before the entry port of the pump 39 for separating sand and other particles out of the hydrocarbons prior to entering the pump.
[0077] The pump 39 controls the rate and pressure at which hydrocarbons from the zone 33 enter the production tubing 38 . Once in the production tubing 38 , hydrocarbons can flow up the tubing, bypassing higher pumps.
[0078] Similarly, pumps 35 , 37 have an entry port with a wire wrapped screen (not shown) to accept hydrocarbons from zones 31 , 32 respectively; arrow ‘A’. The pumps 35 , 37 , 39 are surface controlled and the pressure at which hydrocarbons leave these pumps can be boosted or retarded relative to the formation pressure of the corresponding zones 31 , 32 , 33 . Thus the flow rates and pressure of the hydrocarbons being discharged from each pump 35 , 37 , 39 can be equalised regardless of the potentially differing formation pressures in the zones 31 , 32 , 33 . This enables the hydrocarbons from all zones to mix and proceed together up the production tubing 38 for recovery.
[0079] A sliding sleeve (not shown), or other shut off device such as a check valve, is provided to seal the perforations in the production tubing 32 if any of the pumps 35 , 37 , 39 are removed for maintenance and replacement. The pumps 35 , 37 , 39 can be removed individually on wirelines, leaving the production tubing in place. Thus sliding sleeves used in this way only move to close the perforations in the production tubing and are not used to regulate hydrocarbon flow from the well, as with certain known systems. Since they are therefore used infrequently compared with such known systems, they are far more reliable.
[0080] The pumps 35 , 37 , 39 shown in FIG. 3 are positioned in a side pocket mandrel, such that the installed pumps do not obstruct the production flow path. This construction allows unrestricted wireline access to the bottom of the production tubing.
[0081] “Formation pressure” as used herein is intended to refer to pressure of the zone. This term can encompass the natural pressure of the zone or the natural pressure when artificially enhanced by means such as steam injection.
[0082] Pressure sensing apparatus (not shown) can be provided to measure the pressure differential between the intake and the discharge of the pumps 35 , 37 , 39 . Such data can be transmitted to the surface where a computer (not shown) may be utilised to assimilate and process the information to artificially control pressure and flow at the pumps 35 , 37 , 39 discharge to ensure co-mingled flow of fluids or hydrocarbons from each zone 31 , 32 , 33 .
[0083] Pumps suitable for this application include electric submersible pumps, progressive cavity pumps and jet pumps. Pumps used in the present invention are preferably manufactured from corrosion resistant materials.
[0084] Alternatively, the flow rate through the pump may be calculated rather than measuring the flow rate using sensors. Flow rate and pressure may also be measured in the well connectors.
[0085] The electric submersible pump (ESP) provides a downhole centrifugal pumping system to generate electrically driven artificial lift of fluids passing through the pump. Under certain conditions, they may be used to reduce flow rate and pressure, rather than create more lift. ESPs are useful for recovery of hydrocarbons from zones or formations with high water cuts (percentage of water to oil). Standard ESPs can be customised for multi-zone production.
[0086] Pump motor power can be provided electrically or hydraulically. Electrical power can be transmitted to the pumps using electric cable on the exterior or interior of the production tubing 18 . FIG. 14 shows a first and second pump assembly 701 & 702 supplied by a single 3-core cable. Each pump assembly comprises a pump 720 , a motor 722 and a commutator 724 . The cable comprises an earth core (not shown), a second core operating at +1000 vdc 710 and a third core 712 operating at −1000 vdc. Thus the effective useful power to the pump assemblies 701 , 702 is 2000 v. However, having the cable at positive and negative voltages facilitates the insulation in the cable to cope with a such a large voltage difference of 2000V. The commutators 724 convert this current to an alternating current. Thus a number of different pump assemblies can be ‘daisy chained’ from a common power supply without having to run separate cables down the well. Telemetry can be multiplexed up the DC cables 710 , 712 to allow each motor to be independently controlled from the surface.
[0087] It is also possible to provide a wet-connect, enabling the cable to be positioned within a tubular which carries fluid or hydrocarbons. In the case of a jet pump, hydraulic drive fluid can be transmitted using a hydraulic umbilical positioned either externally or within the production tubing. Alternatively, the hydraulic umbilical can be operated by coiled tubing. Optionally hydraulic drive fluid can be production fluid from the well.
[0088] FIG. 4 shows a further embodiment 50 with pumps 55 , 57 , 59 mounted in a cartridge 58 . Isolation packers 54 are attached to the exterior of the cartridge.
[0089] FIG. 5 shows a further well completion in hydrocarbon containing zones 41 , 42 , 43 with the further embodiment 50 therein. A casing 40 lines the borehole 52 , with production tubing 48 arranged substantially centrally therein. Zonal isolation packers 46 are provided to isolate the annular spaces between the casing 40 and production tubing 48 , above the zones 41 , 42 , 43 .
[0090] The cartridge 58 is lowered into, and linearly aligned with, the production tubing 48 such that a fluid tight seal is created by the packers 54 between the cartridge 58 and the production tubing 48 around the zones 41 , 42 , 43 . The cartridge 58 functions in a similar way to the apparatus shown in FIG. 3 where hydrocarbons from each zone 41 , 42 , 43 , arrow ‘A’, only flow through respective pumps 55 , 57 , 59 with hydrocarbons from each lower zone 42 , 43 bypassing the higher pumps in the production tubing 58 .
[0091] Provision of the cartridge 58 allows the entire unit to be conveniently removed for servicing, repair or replacement of any of the pumps.
[0092] FIGS. 6 and 7 show a more detailed sectional view of a portion of an alternative apparatus and well completion in accordance with the present invention. The well completion has a casing 60 and production tubing 68 . The casing 60 is perforated in the region of zones 61 , 62 , 63 . Either side of these perforations the annular space between the production tubing 68 and the casing 60 is sealed using packers 66 .
[0093] Well connectors or side pocket flow valves 71 , 72 , 73 are provided to allow respective flow from each zone 61 , 62 , 63 therethrough. As shown in FIG. 7 , in use, the valves 71 , 72 , 73 are connected to respective pumping assemblies 75 , 77 , 79 .
[0094] Electrical wet-connects 74 (shown in FIG. 6 ) supply electrical power to drive electric submersible pump assemblies 75 , 77 , 79 (shown in FIG. 7 ) and these wet-connects 74 are located in the annulus between the production tubing 68 and the casing 60 . An electrical conduit (not shown) supplying power to drive the pumps is run down the outside of production tubing 68 to each wet-connect 74 .
[0095] FIG. 7 shows the electric submersible pump assemblies 75 , 77 , 79 suspended within the casing 60 . The pump assemblies 75 , 77 , 79 , connect to the electrical conduit via the wet-connects 74 and to the valves 71 , 72 , 73 .
[0096] Annular flow passages 81 , 82 , 83 are defined between the production tubing 68 and the casing 60 in the region above each pump 75 , 77 , 79 . A series of apertures 84 - 89 is provided in the production tubing 68 adjacent to and above each pump 75 , 77 , 79 to allow for fluid communication between the production tubing 68 and the annular flow passages 81 , 82 , 83 so that flow from below any of the pumps 75 , 77 , 79 is diverted into the adjacent annular flow path 81 , 82 , 83 before mixing with the flow emitted by the pumps 75 , 77 , 79 as described in more detail below.
[0097] The pressure or flow rate of the hydrocarbons emitted from each pump may be continuously adjusted in response to fluctuations in formation pressure. Among the factors that can typically influence the recovery of hydrocarbons from different formations are the different natural formation pressures, different grades of hydrocarbons, well penetration and the ratio of gravity to viscosity of fluid.
[0098] FIGS. 8 a , 8 b , and 8 c show a more detailed view of the pump assembly 77 being run into the well. FIG. 8 a shows the well completion before a pump assembly is run in. FIG. 8 b shows the apparatus of FIG. 8 a with the pump assembly being run into the production tubing 68 using a wire running tool 111 . This example shows the pump assembly 77 being run into the well using a wireline 113 , but coiled tubing may also be used. FIG. 8 c shows the pump assembly 77 connected to the side pocket valve 72 and wet-connect 74 .
[0099] The pump assembly 77 comprises a fluid side pocket sub 124 , a pump 127 , an electric side pocket sub 118 and a motor 116 . The lower end (in use) of the pump 127 is connected to the side pocket sub 124 . The upper end of the pump 127 is connected to the electric side pocket sub 118 . The electric motor 116 , provided to drive the pump 127 , is connected to the upper end (in use) of the electric side pocket sub 118 .
[0100] The detailed view of FIG. 8a shows that side pocket valve 72 comprises a check valve 107 and a fluid connect 101 . The fluid side pocket sub 124 is connectable to the fluid connect 101 . The electric side pocket sub 118 is connectable to the electrical wet-connect 74 . The pump 127 has a pump discharge 122 to enable fluid communication between the pump 127 and annular flow path 82 via the apertures 87 in the production tubing 68 .
[0101] Once the pump assembly 77 is run into the tubing 68 , it is located at the appropriate wet-connect 74 and side pocket valve 72 as shown in FIG. 8 c . There are preferably locating means (not shown) incorporated into the pump assembly 77 and on the production tubing 68 to activate the locating means in the correct position allowing the pump assembly 77 to mate with the wet-connect 74 and side pocket valve 72 .
[0102] An aperture (now shown) is provided in the production tubing 68 adjacent to each side pocket flow valve 71 - 73 to allow fluid produced from any of the pumps below said valves to bypass the respective pumping assembly 75 , 77 , 79 by flowing into the annular flow paths 81 , 82 , 83 .
[0103] Referring to FIG. 8 c , it is illustrated that in use, fluid from lower zone 63 flows up the production tubing 68 as shown by an arrow 133 . This fluid flows through said aperture (not shown) in the production tubing 68 and into the annular flow passage 82 , arrow 134 . It continues up the annular flow passage 82 and mixes with further fluid from the adjacent production zone 62 as described further below.
[0104] Fluid from the production zone 62 adjacent the pump 77 first flows through the check valve 107 as indicated by an arrow 131 . The fluid then flows though the fluid connect 101 to enter the fluid side pocket sub 124 , from where the fluid is drawn into the pump 127 where its pressure and flow rate are equalised with that of the fluid received from the lower zone 63 . The pump 127 is driven by the electric motor 116 . Power for operating the electric motor 116 is supplied via the electric wet-connect 74 and the electric side pocket sub 118 .
[0105] Fluid from the zone 62 proceeds from the pump assembly 77 to the annular flow passage 82 via the pump discharge 122 and apertures 87 in the production tubing 68 . There, it mixes with the fluid from the lower zones, flows past the electric wet-connect 74 , and the combined flow then re-enters the production tubing 68 via the apertures 86 . The packer 66 at the top of the annular flow passage 82 prevents the fluid from continuing up the annular flow passage 82 .
[0106] The combined flow then takes the corresponding route past the upper pump 75 (i.e. diverted via annular flow path 81 ) as described here for flow from the lower pump 79 and corresponding zone 63 .
[0107] In alternative embodiments, the flow released from any of the pumps, for example pump 77 may be released directly into the production tubing 68 above the motor 116 rather than through the apertures 122 .
[0108] A further option is to have pumps and associated assemblies smaller than the production tubing and to have the fluid pumped up through a further annulus between the pumps and the production tubing.
[0109] Pressure of hydrocarbons at the pump discharge can be controlled or boosted by the pump 127 such that they are comparable or equivalent to the pressure and flow rate of hydrocarbons from the other zones.
[0110] One advantage of such embodiments of the present invention is that the risk of cross-flow is reduced because the pressure of the fluid emitted from the various pumps is the same regardless of the pressure in the various production zones to which the pumps communicate.
[0111] A further benefit of certain embodiments of the present invention is that the flow rate of the fluid from different production zones can be boosted to the natural flow rate of the zone with the highest formation pressure, or even higher. Thus hydrocarbons can be recovered much quicker than conventional choke valves which attempt to restrict the flow rate to that produced by the production zone with the lowest formation pressure.
[0112] Instead of or in addition to the wire wrapped screens on the pumps, other suitable filtration methods or sand control techniques such as gravel packing and sand consolidation can be used.
[0113] The embodiment of FIG. 8 a - 8 c may be used in a well with a single production zone. If required during use, the pump 77 can be recovered back to the surface.
[0114] FIGS. 9 a and 9 b illustrate an electrical powered valve assembly 230 being run into the casing 60 using wireline 211 and installed in position within the production tubing 68 shown in FIG. 8 a.
[0115] The electrical pump of FIGS. 8 a and 8 b has been replaced with the electrical powered valve assembly 230 , shown in FIGS. 9 a and 9 b . In this embodiment, production rates of hydrocarbons can be controlled by varying the choke sizes, thereby altering the flow rate. This is a less preferred embodiment since the pressure control is inferior to that afforded by pumps. The valves are however removably connectable to the side pocket valve 72 and can thus be conveniently replaced in the event of failure.
[0116] The valve assembly 230 comprises a fluid side pocket sub 224 , a variable area choke 270 and an electric side pocket sub 218 . The sub 224 is a short adaptor branching the connect 101 and the variable choke area 270 . The upper end (in use) of the fluid side pocket sub 224 is connected to the lower end of the variable area choke 270 . The upper end (in use) of the variable area choke 270 is connected to the electric side pocket sub 218 . The variable area choke 270 adjusts the flow of fluid appropriately and is operated by power supplied by an electrical conduit (not shown) via the electric wet-connect 74 and the electric side pocket sub 218 .
[0117] An arrow 233 illustrates the flow of fluid from lower zones before it bypasses the valve assembly 230 . Fluid from the zone 62 passes check valve 107 and the fluid connect 101 to enter the fluid side pocket sub 224 as shown by an arrow 231 . The fluid passes through variable area choke 270 and exits electric side pocket sub 218 into the production tubing 68 as shown by an arrow 237 . Fluid flowing out of electric side pocket sub 218 mingles with flow from lower zones shown by the arrow 232 on exiting apertures 87 to create a combined flow through the annular flow path 82 .
[0118] The embodiment of FIGS. 9 a - 9 b may be used in a well with a single production zone. If required during use, the valve assembly 230 can be recovered back to the surface.
[0119] An alternative arrangement is shown in FIGS. 10 a and 10 b . FIGS. 10 a and 10 b show similar apparatus to that shown in FIGS., 9 a and 9 b with like components having the prefix “3” instead of “2”. In this embodiment, the valve assembly 330 does not include an electric side pocket sub for connection with the electrical wet-connect 74 . The wet-connect 74 is thus redundant when such an embodiment is used.
[0120] FIG. 10 a shows a variable area choke 370 , being run into the production tubing 68 (shown in FIG. 8 a ) using a wireline 311 . In use formation fluid flows through the check valve 107 and into a fluid side pocket sub 324 via the fluid connect 72 , from where it passes into the variable area choke 370 . The variable area choke 370 controls the rate of flow of fluids exiting the choke shown by an arrow 337 . These fluids progress up the production tubing 68 where apertures 87 in the production tubing 68 allow combined flow and mixing with fluids from lower zones in the annular flow path 82 . The direction fluid flow from lower zones is indicated by arrows 333 and 332 .
[0121] Thus the embodiments using valves and no pumps allow for co-mingled flow. In the event of failure of any of the valves they may be recovered to the surface by a wireline, such as wirelines 211 , 311 .
[0122] Various choke sizes may be used, allowing hydrocarbons to be produced up the tubing from various formation pressures.
[0123] For alternative embodiments of the invention, each producing zone may have a corresponding pump assembly to control the pressure and flow rate of the fluid, except one of the zones, typically the zone with the largest formation pressure. Sensors may be added to such a zone and from these sensors, combined with calculations on the data on the flow rates through the pumps in other zones, the flow rates of the pumps may be manipulated to allow for co-mingled flow.
[0124] The embodiment of FIGS. 10 a - 10 b may be used in a well with a single production zone. If required during use, the valve assembly 330 can be recovered back to the surface.
[0125] In certain embodiments, the pump or valve is provided in a side pocket of the well, as shown in FIGS. 11 a and 11 b . In FIG. 11 a , a casing 502 encloses production tubing 504 . The casing 502 is normally concentric with the production tubing but adjacent to a well connector 510 , the production tubing 504 deviates from concentric alignment with the casing 502 to define a side pocket 508 . The well connector 510 is provided in the side pocket 508 for connection to the pump or valve 506 , as shown in FIG. 11 b . The pump or valve 506 and well connector 510 can function as described for any other embodiment disclosed herein.
[0126] The side pocket may also be provided by a length of production tubing which is wider than the remaining production tubing in order to provide space for the well connector 510 and the pump 506 but still provide access to the well below.
[0127] To launch the pump 506 , it is lowered down through the production tubing 504 . Adjacent to the side pocket 508 , a kick-over tool (not shown) is activated to cause the pump 506 to move into the side pocket 505 through a port 505 in the production tubing 504 . The pump then mates with the well connector 510 .
[0128] Such a configuration allows full bore access through the production tubing 504 to the well below the pump or valve 510 in contrast to certain known designs where such access is not possible.
[0129] The well connector 510 and pump 506 are shown in more detail in FIG. 12 a and FIG. 12 b . The pump has seals 512 surrounding electrical connectors 514 which mate with electrical connectors on the well connector 510 . In use, fluid from the well flows from the well connector 510 into a bore 516 of the pump 508 and then proceeds to the surface via the production tubing 504 . Thus the electrical and fluid connection are conveniently made by the same connection.
[0130] One will appreciate that a plurality of pumps, such as the pump 506 , may be provided in a series of side pockets for a plurality of production zones, as detailed for earlier embodiments. The embodiment of FIGS. 10 a - 10 b may be used in a well with a single production zone.
[0131] In any case, if for any reason a pump needs to be retrieved to the surface, this can be done and without removing any pumps thereabove. Thus the pumps are independently retrievable. Wireline, coiled tubing or pipe may be used to retrieve the pumps.
[0132] For certain embodiments, a well connector may be provided in a side pocket such that it receives a pump assembly/valve etc from below. This provides the benefit that when the well connector is not engaged with a pump/valve etc, fluids are less liable to enter the well connector 510 and damage components therein or inhibit a subsequent connection. A pump assembly can be mated with the well connector in a similar way—a kick-over tool moves the pump assembly transversely when it passes a port below the well connector. The pump assembly is then moved in an upwards direction in order to connect the pump assembly and the well connector.
[0133] A further embodiment of a valve assembly 430 in accordance with one aspect of the present invention is shown in FIGS. 13 a to 13 d . The valve assembly 430 comprises a first upper portion 491 shown in FIG. 13 b and a second lower portion 492 shown in FIG. 13 a.
[0134] Referring to FIG. 13 b , the upper portion 491 comprises a housing 480 with a fishing neck exterior 481 , and a central bore 482 . An aperture 496 is provided in the housing 480 to allow production fluid to exit the bore 482 of the housing 480 to the exterior of the valve assembly 430 .
[0135] A piston 493 is provided in the housing 480 and is connected to a spear valve 495 , which in use regulates the access for fluid to exit the valve assembly 430 via the aperture 496 .
[0136] At a head 493 H of the piston 493 , a hydraulic chamber 497 is defined by seals 498 . A hydraulic line 499 leads to said hydraulic chamber 497 which in use controls movement of the piston 493 and attached spear valve 495 , as described below. A spring 494 urges the piston 493 to return the spear valve 495 to its closed position in the absence of any other forces.
[0137] A J-pin 489 , shown in FIG. 13 e , is provided in a slot 480 S in the housing 480 and can engage with recesses 493 R and 493 R′ in the piston 493 in order to hold the piston 493 in a position which corresponds to a valve fully open position, a valve closed position, and a number of intermediate positions. Alternatively the hydraulic pressure in the hydraulic chamber 497 may be varied in order to allow the piston 493 and valve 495 to adopt any position between the valve fully open and the valve closed position.
[0138] Referring to FIG. 13 a , the lower portion 492 of the valve assembly 430 comprises a housing 580 , a central bore 582 , a hydraulic line 599 and a hydraulic input 570 . The hydraulic input 570 of the lower portion 492 is connected to a hydraulic line which is provided within the annulus between production tubing and casing of the well (not shown) in which the valve assembly 430 is operated.
[0139] In use, the upper portion 491 is landed on the lower portion 492 , as shown in FIG. 13 c , such that the lower portion 492 is inserted into the bore 482 of the upper portion 481 . Seals 571 and 572 seal the portions together around their respective hydraulic lines 499 , 599 which align together. The spear valve 493 of the upper portion 481 seals the bore 582 of the lower portion.
[0140] In use production fluid is produced and directed up the bore 582 of the lower portion 492 by a connection (not shown) with the producing zone, typically via a valve such as a side pocket flow valve 72 shown in FIG. 8 a . When the spear valve 493 is in its closed position, as shown in FIG. 13 c , the production fluid cannot flow any further.
[0141] To operate the valve assembly 430 the hydraulic line is pressurised at the surface, which in turn pressurises the hydraulic lines 599 , 499 and hydraulic chamber 497 to urge the piston 493 in an upwards direction against the action of the spring 494 . Movement of the piston 493 causes the connected spear valve 495 to move and gradually allow access between the bore 482 of the housing 490 and the exterior of the valve assembly 430 via the aperture 496 . Thus the amount of fluid flow permitted between these two regions can be controlled by the pressure of the hydraulic fluid applied to the hydraulic chamber 497 . In particular the valve functions as a proportional valve—allowing a proportion of the production fluid to flow through the aperture 496 depending on that required by an operator or computer controller. The J-pin can maintain the piston 493 and valve 495 in a number of positions allowing the hydraulic pressure to be released from the hydraulic chamber 497 .
[0142] The desired amount of fluid can then flow from the bore 582 of the lower portion through the aperture 496 and outside of the valve assembly 430 . The fluid continues up the production tubing to the surface.
[0143] The aperture 496 may be aligned with an aperture in the production tubing to allow fluid to flow into the annulus between the production tubing and casing. Alternatively the fluid can proceed up the production tubing between the valve assembly 430 and the production tubing.
[0144] A series of such valve assemblies can be provided and the flow rate of the production fluid controlled via the proportional valves such that flow from a plurality of production zones can be recovered simultaneously.
[0145] A benefit of certain embodiments of the invention, such as those shown in FIGS. 13 a - 13 e , is that they can be easily retrieved from the well for maintenance or for other reasons. In contrast sliding sleeves, known in the art, are difficult to maintain and repair in the event of failure.
[0146] In further embodiments, a side-pocket may be provided in the production tubing, with an on/off valve, such as the side pocket flow valve 72 , provided in said side-pocket. A proportional valve, similar to that shown in FIGS. 13 a - 13 d , may be lowered into said side pocket and connected to the on/off valve. The hydraulic power is preferably provided by a line which extends from the surface down the well between the production tubing and the casing.
[0147] Although the embodiments show zones in vertically spaced formations, the apparatus and method of the present invention may also be used to retrieve fluid from lateral bores.
[0148] Improvements and modifications may be made without departing from the scope of the invention.
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A method of obtaining fluid, typically hydrocarbons, from a first production zone and a second production zone, the method comprising: (a) providing a first pump or valve to produce or control flow of fluid from the first production zone; (b) in a well, providing a first well connector proximate to, and in fluid communication with, the first production zone; (c) connecting the first device to the first well connector; (d) providing a second pump or valve to produce or control flow of fluid from the second production zone; (e) in the well, providing a second well connector proximate to, and in fluid communication with, the second production zone; (f) connecting the second device to the second well connector; (g) producing fluids from the first and second production zones through the well connectors.
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CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims priority to German Patent Application No. 10 2015 221 877.5 filed on Nov. 6, 2015, the entirety of which is incorporated by reference herein.
BACKGROUND
[0002] The instant invention relates to an imaging-based biomarker for characterizing the structure or function of human or animal brain tissue and to two methods for characterizing the structure or function of human or animal brain tissue by using such a biomarker.
[0003] Biomarkers, especially biomarkers derived from magnetic resonance (MR), positron emission tomography (PET) or magnetic particle images, allow detection and quantitative characterization of structural or functional alterations of the human or animal brain which can occur in association with various diseases including, but not restricted to cerebrovascular, neurodegenerative, and inflammatory diseases. By this, biomarkers based on these imaging modalities may support diagnosis, therapy planning and therapy monitoring in clinical routine patient care. Such biomarkers may also play an important role in the development of new treatments, new drugs and non-pharmacological treatment options, not only by supporting the inclusion of appropriate patients into clinical trials but also by providing objective outcome measures for the evaluation of therapy effects.
[0004] Biomarkers contribute to improved accuracy of a diagnosis compared to conventional clinical diagnosis using only symptom-based criteria. This is achieved by providing evidence of the patho-physiological changes in the brain characteristic for the underlying disease.
[0005] Cerebrovascular diseases' is the umbrella term for diseases that affect blood vessels supplying and draining the brain. Cerebrovascular diseases can affect small and/or large vessels. Cerebrovascular disease can be detected in MR images of the brain in which it manifests with a variety of different structural lesions including (but not restricted to) large infarcts, recent small subcortical infarcts, lacunes, subcortical hyperintensities, perivascular spaces, microbleeds, and brain atrophy [1].
[0006] MR imaging generally allows detection and quantitative characterization of structural lesions in the human or animal brain including (but not restricted to) those associated with cerebrovascular disease.
[0007] For example, subcortical hyperintensities are per definition present as hyperintensities in T2-weighted MR images and are located within the brain's white matter or in subcortical grey matter or in the brainstem. Thus, subcortical hyperintensities are lesions (within the specified brain regions) that appear brighter than normal in T2-weighted MR images. They can be easily detected by visual inspection of T2-weighted MR images (see FIG. 1A ).
[0008] Structural lesions in the brain very commonly occur in older age so that virtually all elderly people show structural brain lesions, although to a strongly variable extent. Structural brain lesions can be associated with the whole spectrum of cognitive decline/dysfunction, ranging from subjective cognitive decline over mild cognitive impairment to dementia affecting activities of daily living. However, structural brain lesions can be present also without causing any symptoms. Thus, it is an important diagnostic problem to decide whether the structural brain lesions detected in a given patient are the cause of his cognitive decline or not. In the latter case, the patient should be referred to further diagnostic tests in order to identify the underlying disease, for example Alzheimer's disease.
[0009] The reliable detection of the cause of cognitive decline, for example the differentiation between vascular cognitive decline and Alzheimer's disease, has immediate therapeutic consequences: reducing risk factors in order to avoid progression in vascular cognitive decline versus cholinesterase inhibitors in Alzheimer's disease. Another, clinically highly relevant diagnostic problem is the estimation of the risk associated with detected structural brain lesions, for example the risk of cognitive decline or the risk of stroke in the future.
[0010] There is increasing evidence in the scientific literature that the pattern of the brain lesion load provides information that is relevant to both questions, i.e. differential diagnosis and risk stratification.
[0011] Nevertheless, in clinical routine patient care brain lesion load is usually assessed only qualitatively or using a visual scoring system [ 2 ]. However, these visual scores have been shown to be quite variable not only between different raters (low inter-rater stability) but also when the same rater repeats the scoring of the same image (low intra-rater stability). This clearly limits the usefulness of these visual scores.
[0012] Quantitative assessment of structural brain lesions was previously performed by manual lesion delineation, by automatic lesion segmentation algorithms or by a combination of both [3-8]. Most of the described semi-automatic software tools provide the option for localization of detected lesions, both on the basis of brain regions predefined in an anatomical standard (atlas) space or by using parcellation techniques.
[0013] It is further known from prior art to define an ‘asphericity’ of a tumor in whole body positron emission tomography (PET) with the glucose analog [F-18]-fluorodeoxyglucose (FDG) [9-11]. The asphericity in FDG PET is a measure of the shape irregularity of the metabolically active part of the tumor and has been proposed to predict the survival time of tumor patients. The asphericity is applied to a single tumor lesion. It has not been applied to several lesions or lesion patterns. As a consequence, the asphericity of a tumor has never been weighted in any way.
[0014] Positron emission tomography of the brain with the glucose analog F-18-fluorodeoxyglucose (FDG PET) provides biomarkers for altered (synaptic) brain function. Alterations of brain function can be caused by loss/dysfunction of neurons indicative of a neurodegenerative disease, e.g. Alzheimer's disease (AD).
[0015] U.S. Pat. No. 6,366,797 B1 describes a method of analyzing magnetic resonance images of a brain to determine the severity of a medical condition by calculating a ratio between the brain volume and volume of a specific area within the brain.
[0016] U.S. Pat. No. 7,995,825 B2 describes a method of classifying tissue in a magnetic resonance image by constructing a pixel intensity histogram of a previously acquired magnetic resonance image and applying a statistical regression analysis to the histogram to determine a pixel intensity threshold value for segmenting the histogram into at least two regions.
[0017] US 2003/0088177 A1 describes a method for assessing a neurological condition of a patient by identifying a biomarker of the nervous system of the patient in a three-dimensional image and by storing an identification of the biomarker and a quantitative measurement thereof in a storage medium. The biomarker can be a shape, topology, and morphology of brain lesions, of brain plaques, of brain ischemia, or of brain tumors; a spatial frequency distribution of sulci and gyri; a compactness of grey matter and white matter; whole brain characteristics; grey matter characteristics; white matter characteristics; cerebral spinal fluid characteristics; hippocampus characteristics; brain sub-structure characteristics; a ratio of cerebral spinal fluid volume to grey matter and white matter volume; and a number and volume of brain lesions.
[0018] U.S. Pat. No. 8,112,144 B2 describes a cerebral atrophy assessment device that is arranged and designed to calculate a numerical value representing a volume of a convex hull of the grey matter or the white matter of a brain, and to calculate a value of a first ratio between this numerical value and a numerical value representing the brain volume. Afterwards, a cerebral atrophy is assessed from the value of the first ratio.
[0019] U.S. Pat. No. 8,423,118 B2 describes a system for automated differential diagnosis of dementia, including a knowledge base that comprises a plurality of brain scan images exhibiting patterns of a plurality of types and degrees of dementia and one or more healthy brain scan images, wherein diagnosis information can be output by the system that includes an image of the patient's brain scan image with highlighted hypo-metabolic regions, wherein the highlighting is color-coded to indicate a type of dementia, wherein different colors correspond to different types of dementia.
[0020] The impact of structural brain lesions including white matter hyperintensities (WMHs) on cerebral glucose metabolism is well-documented in the literature. Kochunov et al (2009) [12] documented the association between WMH burden and global reduced cerebral glucose metabolism. Tullberg et al. (2004) [13] and Reed et al. (2004) [14] found a strong association between WMHs and a regional decline in cerebral glucose metabolism most pronounced in the frontal lobes. A recent work by Glodzik et al. (2014) [15] demonstrated that disruption of white matter tracts connecting grey matter regions caused by structural brain lesions results in a decline in glucose metabolism in connected grey matter regions.
SUMMARY
[0021] It is an object of the instant invention to provide novel imaging-based biomarkers that provide more reliable results than biomarkers known from prior art when characterizing the structure or function of human or animal brain tissue. It is a further object of the instant invention to provide methods implementing the use of the biomarkers.
[0022] This object is addressed by an imaging-based biomarker having the features as described herein. Such a biomarker is suited for characterizing the structure or function of human or animal brain tissue, in particular of a human or animal brain or parts thereof. Thereby, it is particularly suited to characterize abnormal brain tissue, i.e. brain tissue containing unusual (altered in comparison to a healthy standard population) or diseased cells or areas.
[0023] The imaging-based biomarker is based on an image of the brain tissue (e.g. of a brain or a part of a brain in its native surrounding, i.e. within a head of a living subject), the image showing at least one brain lesion and containing information on a surface and a volume of the brain lesion (in particular, if a three-dimensional image is considered) or on a circumference and an area of the brain lesion (in particular, if a two-dimensional image is considered). A plurality of brain lesions constitutes a lesion map which is a suited image within the framework of the instant disclosure.
[0024] The biomarker is chosen from the group consisting of a weighted confluency sum score (WCSS) and a percent shielding by brain lesions (SbBL). Thereby, WCSS is a weighted sum of a measure for a relationship between the surface area and the volume of brain lesions (if a three-dimensional image is considered) or between a circumference and an area of brain lesions (if a two-dimensional image is considered) over at least one identified brain lesion. Specifically, the weighted confluency sum score is a sum of weighted confluencies over at least two or more brain lesions on the image.
[0025] Thereby, the confluency of a brain lesion is a measure of a relation between a surface area of the brain lesion and a volume of the brain lesion or between a circumference of the brain lesion and an area of the brain lesion.
[0026] In addition, the percent shielding by brain lesions (SbBL) of a brain area is a measure for a fraction of a surrounding of the considered brain area belonging to a brain lesion. The brain lesions can be represented on the image as single voxels or single pixels or as clusters of contiguous voxels or pixels.
[0027] The percent shielding by brain lesions is a suited marker to evaluate remote effects of brain lesions. It turned out that the higher the shielding of a selected brain area by brain lesions the higher is the (impairing) effect of these brain lesions on remote brain areas that are not part of brain lesions. This can be explained by a loss of communication possibilities between remote (and unaffected) brain areas and the brain area that is (highly) shielded by brain lesions. The brain lesions interrupt otherwise existing communication channels between the remote brain areas and the brain area that is shielded by brain lesions.
[0028] Generally, the brain lesion can be, e.g., a cortical lesion, a subcortical lesion, a hyperintensity lesion and/or a hypointensity lesion such as, e.g., a cortical hyperintensity lesion, a subcortical hyperintensity lesion, a cortical hypointensity lesion or a subcortical hypointensity lesion.
[0029] In an embodiment, the weighted confluency sum score is proportional to the (cubic) root of the ratio between the optionally exponentiated surface of the brain lesion and the optionally exponentiated volume of the brain lesion, e.g.:
[0000]
WCSS
~
surface
x
volume
y
z
[0000] wherein
x is 1, 2, 3 or 4, y is 1, 2, 3 or 4, and z is 2, 3 or 4.
[0033] Suited examples of formulae for calculating the weighted confluency sum score are:
[0000]
WCSS
~
surface
volume
WCSS
~
surface
2
volume
2
WCSS
~
surface
2
volume
WCSS
~
surface
3
volume
3
WCSS
~
surface
3
volume
3
3
WCSS
~
surface
3
volume
2
3
[0034] In an embodiment, the weighted confluency sum score is proportional to the root of the ratio between the optionally exponentiated circumference of the brain lesion and the optionally exponentiated area of the brain lesion, e.g.:
[0000]
WCSS
~
circumference
x
area
y
z
[0000] wherein
x is 1, 2, 3 or 4, y is 1, 2, 3 or 4, and z is 2, 3 or 4.
[0038] Suited examples of formulae for calculating the weighted confluency sum score are:
[0000]
WCSS
~
circumference
area
WCSS
~
circumference
2
area
2
WCSS
~
circumference
2
area
[0039] In an embodiment, the weighted confluency sum score is calculated according to formula (I):
[0000]
WCSS
=
∑
i
w
i
·
confluency
i
(
I
)
[0040] The so-called confluency i referred to in formula (I) is a measure for the sphericity of individual brain lesions. It is calculated in an embodiment according to formula (II) or to formula (III):
[0000]
confluency
i
=
1
36
·
π
·
surf
i
3
vol
i
2
3
-
1
(
II
)
confluency
i
=
1
4
·
π
·
circf
i
2
area
i
-
1
(
III
)
Thereby,
[0000]
WCSS stands for weighted confluency sum score,
i is a summation index running over all or any subset of the brain lesions depicted on the image of the brain tissue,
w i is a weighting factor quantifying the relevance of the i th brain lesion for a considered application,
surf i represents an estimate of the surface area of the i th brain lesion,
vol i represents an estimate of the volume of the i th brain lesion,
circf i represents an estimate of the circumference of the i th brain lesion, and
area i represents an estimate of the area of the i th brain lesion.
[0048] In an embodiment, the percent shielding by brain lesions of a brain area (denoted as A) is computed as the percentage of image voxels (in particular in case of a three-dimensional image) or image pixels (in particular in case of a two-dimensional image) belonging to a brain lesion in a predefined volume or area (denoted as B) surrounding the considered brain area.
[0049] In an embodiment, the percent shielding by brain lesions is a percent shielding by white matter hyperintensities. In an embodiment, this is calculated according to the following formula (IV):
[0000]
SbWMH
A
=
100
*
V
B
(
WMH
)
V
B
(
IV
)
Thereby,
[0000]
SbWMH A stands for percent shielding of brain region A by white matter hyperintensities (WMHs), and
V B stands for the total number of voxels or pixels in brain area B surrounding A
V B (WMH) stands for the number of voxels or pixels in brain area B belonging to a WMH
[0053] In contrast to prior art, the weighted confluency sum score (WCSS) makes use of a weighting of individual observed brain lesions according to their significance. From prior art, no such weighting of individual observed brain lesions has been described. In addition, prior art does not give any suggestion to calculate a sum score of a confluency of several individual brain lesions to obtain a biomarker. In fact, no biomarker has been described in prior art that describes the pattern of a degree of confluency of brain lesions in the brain, as, e.g., observed in magnetic resonance images.
[0054] The novel biomarkers described here each allow quantitative and rater-independent characterization of the structure of the analyzed brain, in particular of brain lesions and thus of brain lesion load in the analyzed brain. They also allow the quantitative and rater-independent characterization of the impact of the brain lesion load on the function of the analyzed brain.
[0055] According to prior art, the total volume (in ml) of brain lesions throughout the whole brain is considered to be of particular relevance. However, within the scope of this invention, it was found out that the shape of brain lesions and their location within the brain appear to provide additional useful information.
[0056] The novel biomarkers provide information that is independent of the total volume of brain lesions and, therefore, might be particularly useful in combination with the total volume of brain lesions (multivariate model).
[0057] The used image can be a two-dimensional or three-dimensional image. In case of a two-dimensional image, such as an image of a (virtual) section through a brain, it is often known which depth can be assigned to this section. With this depth information, the two-dimensional image can also be regarded as three-dimensional image. In addition, a stack of several two-dimensional images can be mapped together in order to generate a (virtual) three-dimensional image of the brain or part of the brain. All these techniques are well known for a person skilled in the art.
[0058] Prior art, in particular literature references [12] to [15], do not suggest at all that the shielding of cortical grey matter by brain lesions such as WMH could be used as a biomarker. However, it will become apparent from the instant disclosure that a percent shielding by brain lesions such as white matter hyperintensities is a very well suited biomarker, e.g., to characterize the impact of cerebrovascular white matter disease on cortical glucose metabolism.
[0059] In an embodiment, the biomarker SbBL is based on the detection of brain lesions in fluid-attenuated inversion recovery magnetic resonance imaging (FLAIR-MRI) as a marker of impairment of axonal connections. The shielding expressed by the biomarker SbBL can, e.g., be used for quantitative characterization of the impact of impaired axonal connections on cortical brain activity as measured by FDG PET.
[0060] In an embodiment, the animal brain is the brain of a mammal, in particular of a rodent. Thus, the biomarkers can also be used for characterization of the structure or function of the brain in preclinical research (animal imaging).
[0061] In an embodiment, the confluency as defined according to formula (II) is scaled such that the confluency is 0 for a sphere and larger than 0 for all other shapes. In practice, the computation of the confluency is limited by the fact that images are composed of voxels with a given voxel size. Thus, there is no perfect sphere in images, but only ‘edgy’ approximations of a sphere composed of cubic voxels. Computer simulations that will be explained in more details below with respect to the Figures showed that the resulting error in the confluency can be neglected for spheres composed of at least 100 voxels. In an embodiment, the brain lesions therefore comprise at least 100 voxels or pixels, in particular at least 150 voxels or pixels, in particular at least 200 voxels or pixels, in particular at least 250 voxels or pixels, in particular at least 300 voxels or pixels, in particular at least 350 voxels or pixels, in particular at least 400 voxels or pixels, in particular at least 450 voxels or pixels and very particular at least 500 voxels or pixels on the image.
[0062] Since brain lesions are regularly defined by their occurrence and detectability in images obtained by magnetic resonance imaging, the analyzed image is, in an embodiment, a magnetic resonance image. A suited recordation variant for recording such a magnetic resonance image is fluid-attenuated inversion recovery (FLAIR) magnetic resonance imaging.
[0063] Alternatively, the image can be obtained by magnetic particle imaging or by positron emission tomography.
[0064] While different kinds of magnetic resonance images could be generally used to detect brain lesions, T1-weighted and/or T2 (including FLAIR)-weighted and/or T2*-weighted magnetic resonance images are particularly suited for detecting brain lesions.
[0065] In an aspect, the invention relates to the use of the imaging-based biomarker according to the preceding explanations for characterizing the structure or function of a human or animal brain on the basis of an analysis of the image of the brain. Thereby, the image is suited to detect brain lesions on it. These brain lesions may be, e.g., white matter hyperintensities or grey matter hypo- or hyperintensities.
[0066] In an aspect, the invention also relates to a method for characterizing the structure or function of human or animal brain tissue on the basis of an analysis of the image of the brain tissue by using the imaging-based biomarker according to the preceding explanations. Thereby, the image is suited to detect brain lesions on it.
[0067] In an aspect, the invention relates to the use of the imaging-based biomarker according to the preceding explanations for characterizing a brain lesion load in human or animal brain tissue on the basis of an analysis of an image of the brain tissue. Thereby, the image is suited to detect brain lesions on it.
[0068] In an aspect, the invention also relates to a method for characterizing a brain lesion load in human or animal brain tissue on the basis of an analysis of the image of the brain tissue by using the imaging-based biomarker according to the preceding explanations. Thereby, the image is suited to detect brain lesions on it.
[0069] In an aspect, the invention relates to the use of the imaging-based biomarker according to the preceding explanations for diagnosing a disease, for differentiating between different diseases (differential diagnosis), in particular for differentiating between a neurodegenerative disease and a cerebrovascular disorder of a subject, or for monitoring the time course of a change of brain structure or function, with or without treatment on the basis of an analysis of an image of brain tissue, such as of the brain. Thereby, the image is suited to detect brain lesions on it.
[0070] In an aspect, the invention also relates to a method for diagnosing a disease, for differentiating between different diseases (differential diagnosis), in particular for differentiating between a neurodegenerative disease and a cerebrovascular disorder of a subject, or for monitoring the time course of a change of brain structure or function, with or without treatment on the basis of an analysis of an image of brain tissue, such as of the brain, by using the imaging-based biomarker according to the preceding explanations. Thereby, the image is suited to detect brain lesions on it.
[0071] Further uses of the biomarker or methods using the biomarker relate to the detection of the cause of cognitive decline of a subject suffering from cognitive decline. Further uses of the biomarker or methods using the biomarker relate to the differentiation between a disease state that is caused by loss/dysfunction of neurons and a disease state that is caused by alterations of blood flow in the brain tissue of a subject.
[0072] In an embodiment, the neurodegenerative disease is Alzheimer's disease.
[0073] In an aspect, the invention relates to the use of the imaging-based biomarker according to the preceding explanations for an assessment or stratification of the risk associated with detected subcortical hyperintensities regarding the development of future brain disorders or brain-related diseases, such as the risk of cognitive decline or the risk of stroke within a defined period of time. This defined period of time may be, e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10 years. This risk assessment or risk stratification is carried out once again on the basis of an analysis of an image of brain tissue. Thereby, the image is suited to detect brain lesions on it.
[0074] In an aspect, the invention also relates to an according method for an assessment or stratification of the risk associated with detected subcortical hyperintensities regarding the development of future brain disorders or brain-related diseases, on the basis of an analysis of the image of brain tissue by using the imaging-based biomarker according to the preceding explanations. Thereby, the image is suited to detect brain lesions on it.
[0075] In an aspect, the invention relates to a first method for characterizing the structure or function of human or animal brain tissue. Thereby, the method comprises the steps explained in the following.
[0076] In a first method step, an image of human or animal brain tissue is provided. Thereby, the image is suited to detect brain lesions on it.
[0077] In another method step, one or more brain lesions are—in particular automatically—detected on the image and their outer contour is—in particular automatically—delineated.
[0078] In another method step, a confluency is computed for each delineated brain lesion, wherein the confluency is a measure of a relation between a surface area of the brain lesion and a volume of the brain lesion or between a circumference of the brain lesion and an area of the brain lesion.
[0079] In another method step, a weighted confluency sum score is computed as a sum of weighted confluencies over each delineated brain lesion.
[0080] In another method step, the weighted confluency sum score is used to characterize the structure or function of the human or animal brain tissue, the image of which has been analyzed.
[0081] In an embodiment, a weighting factor w i is automatically assigned to each delineated brain lesion. The weighting factor w i quantifies the relevance of the i th lesion for the diagnostic indication of interest. The larger the weighting factor the larger the relevance of the respective lesion. The weighting factor can, e.g., take either continuous (real number) or discrete (integer or rational number) values.
[0082] The weighted confluency sum score (WCSS) does not only provide information on the confluency of the detected brain lesions, but also significance-weighted information on the relevance of the respective brain lesions. Therewith, much more significant, reliable and relevant information is obtained about the brain lesions observed in an image of the brain than according to methods known from prior art.
[0083] The method steps can be, but need not be performed in the sequence indicated above. Herewith disclosed is also any other suited method step sequence that can be applied in order to obtain the weighted confluency sum score (WCSS).
[0084] In an embodiment, the weighted confluency sum score (WCSS) is computed according to formula (I):
[0000]
WCSS
=
∑
i
w
i
·
confluency
i
,
(
I
)
Thereby,
[0000]
WCSS stands for weighted confluency sum score, and
i is a summation index running over all or any subset of brain lesions delineated on the image of the brain,
[0087] In an embodiment, the confluency is calculated according to formula (II) or to formula (III):
[0000]
confluency
i
=
1
36
·
π
·
surf
i
3
vol
i
2
3
-
1
(
II
)
confluency
i
=
1
4
·
π
·
circf
i
2
area
i
-
1
(
III
)
[0000] wherein
w i is a weighting factor quantifying the relevance of the i th brain lesion for a considered application, surf i represents an estimate of the surface area of the i th brain lesion, vol i represents an estimate of the volume of the i th brain lesion, circf i represents an estimate of the circumference of the i th brain lesion, and area i represents an estimate of the area of the i th brain lesion.
[0093] In an embodiment, the weighting factor is different for brain lesions located within different brain regions. In doing so, the relevance of the location of the brain lesion for the specific problem to be solved is adequately regarded.
[0094] In an embodiment, the weighting factor is different for brain lesions that are located within cortical grey matter, within periventricular white matter, within deep white/grey matter, within subcortical white matter, or within the brain stem. Thereby, brain lesions that are located within the brainstem are to be considered as the most relevant brain lesions. The highest weighting factor should be assigned to these brain lesions. The second most relevant brain lesions are those located within subcortical white matter. The second highest weighting factor should be assigned to these brain lesions. The third most relevant brain lesions are located within deep white/grey matter. The third highest weighting factor should be assigned to these brain lesions. The fourth most relevant brain lesions are located within periventricular white matter. The fourth highest weighting factor should be assigned to these brain lesions.
[0095] The weighting factors assigned to the individual brain lesions can be arbitrarily chosen. In an embodiment, the weighting factor is set to be 1 if the brain lesion is located within periventricular white matter. Additionally, it is set to be 2 if the brain lesion is located within deep white/grey matter. Furthermore, it is set to be 3 if the brain lesion is located within subcortical white matter. Finally, it is set to be 4 if the brain lesion is located within the brain stem. The numerical differences between these weighting factors are sufficient to adequately weight the individual brain lesions so as to produce a significant biomarker, namely the weighted confluency sum score (WCSS).
[0096] It might be the case that a detected brain lesion is located in (or spread over) more than one brain region. In such a case, the highest weighting factor of the respective brain regions is assigned to this brain lesion in an embodiment.
[0097] In an aspect, the invention relates to a second method for characterizing the structure or function of human or animal brain tissue. Thereby, the method comprises the steps explained in the following.
[0098] In a first method step, an image of human or animal brain tissue is provided, which is suited to detect brain lesions on it.
[0099] In another method step, at least one brain lesion on the image is—in particular automatically—detected and its outer contour is—in particular automatically—delineated. Thereby, a brain lesion map is obtained.
[0100] In another method step, a percent shielding by brain lesions for at least one selected brain area is computed, wherein the percent shielding by brain lesions of the selected brain area is a measure for a fraction of the surrounding of the selected brain area belonging to a brain lesion.
[0101] In another method step, the percent shielding by brain lesions of the at least one selected brain area is used to characterize the structure or function of the human or animal brain tissue, the image of which has been analyzed.
[0102] The selected brain area can be one voxel or one pixel or it can comprise an area or a volume of, e.g., 10 ml or more, 20 ml or more, 30 ml or more, 40 ml or more, 50 ml or more, 60 ml or more, 70 ml or more, 80 ml or more, 90 ml or more, or 100 ml or more. The surrounding volume referred to above can have the same values.
[0103] In an embodiment, the selected brain areas for computing their percent shielding by brain lesions are selected according to the following method steps.
[0104] In a first method step, a second image of the same human or animal brain tissue is provided, wherein the second image is suited to provide different information about brain structure or function than the first image. To give an example, the second image might be suited to provide information on (synaptic) function and dysfunction of the brain tissue. Usually, the second image is obtained by a different imaging technique than the first image.
[0105] In another method step, the lesion map is anatomically mapped (co-registered) with the second image.
[0106] In another method step, the mapped (co-registered) lesion map and the second image are stereotactically normalized into an anatomical standard space. This anatomical standard space can also be denoted as template or atlas space. A normalized second image is obtained.
[0107] In another method step, the normalized second image is compared with at least one equivalent reference image from at least one reference subject to generate an effect map indicating brain areas in which a property (such as an intensity) of the second image differs from the reference image. The effect map can be, e.g., a hypometabolism map indicating hypometabolic areas or voxels in the brain. This comparison can be done, in an embodiment, on the level of voxels or pixels.
[0108] In an embodiment, the comparison is a statistic comparison, leading, e.g., to a statistical parametric map of hypometabolism for the respective brain. Other comparison techniques are also possible. Instead of the single healthy control subject, a group of healthy control subjects (healthy control database) can be used for comparison.
[0109] In another method step, the percent shielding by brain lesions is computed for each brain area on the effect map.
[0110] To give an example, a percentage shielding by white matter hyperintensities can be computed for each hypometabolic voxel as fraction of neighboring (in a predefined volume) white matter voxels affected by white matter hyperintensities.
[0111] The structural or functional characterization of the brain tissue can then be used to differentiate between a cerebral vascular disease and a neurodegenerative disease. In particular, by applying the biomarker SbWMH (being an example of the biomarker SbBL) the risk of misinterpreting WMH-associated alteration in FDG PET as indication of a neurodegenerative disease is significantly reduced.
[0112] The method steps can be, but need not be performed in the sequence indicated above. Herewith disclosed is also any other suited method step sequence that can be applied in order to obtain the biomarker SbBL.
[0113] In an embodiment, the first image is recorded by structural MRI, such as FLAIR MRI or T1-weighted MRI.
[0114] In an embodiment, the second image is recorded by positron emission tomography with F-18-fluorodeoxyglucose (FDG PET).
[0115] In an embodiment, the percent shielding by brain lesions (SbBL) is computed for each pixel or voxel in the effect map and then overlaid to the second image so as to better visualize percent shielding. The resulting image can be compared to an analogous image in which the effect map is overlaid to the second image. Visual side-by-side inspection of these 2 images simplifies the interpretation of SbBL.
[0116] The methods explained above are usually carried out for assessing previously obtained images. Thus, they can also be referred to as in vitro methods. In an aspect of the instant invention, the methods explained above can alternatively or additionally be carried out during recordation of the images to be analyzed. In this aspect, the methods can also be referred to as in vivo or in situ methods.
[0117] The methods explained above are usually carried out to provide original data that can later on be used for helping a physician in making a diagnosis on a certain disorder or disease. In an aspect, the claimed methods encompass the step of making such a diagnosis.
[0118] The methods explained above can be carried out by a (computer) system for fully automatic determination of the described biomarkers, utilizing images, such as MR images, of the human or animal brain. Such a system comprises different means for carrying out the individual tasks to accomplish the method.
[0119] In an aspect, the invention relates to a computer program product that is able to carry out at least one method according to any of the preceding explanations when it is executed on a computer.
[0120] In another aspect, the invention relates to a non-transitory computer readable medium on which a brain structure assessment program is stored that causes an information processing device (such as a computer) to execute at least one method according to any of the preceding explanations.
[0121] The embodiments described above can be combined in any desired way. In addition, embodiments explained with respect to any of the described biomarkers, the described uses, the described methods and the described computer program can be transferred to any other of the described biomarkers, the described uses, the described methods and the described computer program in any desired way.
BRIEF DESCRIPTION OF THE DRAWINGS
[0122] Aspects of the invention will be explained more detail with respect to Figures and exemplary embodiments.
[0123] FIG. 1A shows a transversal slice of a FLAIR-MR image without delineation of subcortical hyperintensities.
[0124] FIG. 1B shows a transversal slice of a FLAIR-MR image with delineation of subcortical hyperintensities.
[0125] FIG. 2A shows transversal slices of an anatomical map of a brain.
[0126] FIG. 2B shows slices from a T1-weighted MR image corresponding to the slices of FIG. 2A for anatomical orientation.
[0127] FIG. 3 shows the results of a computer simulation of spheres composed of a varying number of cubic voxels.
[0128] FIG. 4A shows the results of a computer simulation of a confluency sum score of differently shaped lesions in transversal view.
[0129] FIG. 4B shows the results of a computer simulation of a confluency sum score of differently shaped lesions in coronal view.
[0130] FIG. 5 shows the confluency score of cuboids having different lengths.
[0131] FIG. 6 shows a receiver-operating characteristic (ROC) curve of the WCSS for differentiation between patients with vascular cognitive decline and patients without relevant cerebrovascular disease.
[0132] FIG. 7A shows FDG PET images of the brain in a patient with Alzheimer's disease.
[0133] FIG. 7B shows FDG PET images of the brain in a healthy subject.
[0134] FIG. 8A shows FDG PET images of the brain in a patient who was suspected to have Alzheimer's disease.
[0135] FIG. 8B shows T1-MR images of the same patient as in FIG. 8A .
[0136] FIG. 9A shows a parametric hypometabolism map overlaid to FDG PET images of the brain of a patient.
[0137] FIG. 9B shows a parametric SbWMH map and a WMH lesion map overlaid to FDG PET images of the brain of the same patient as in FIG. 9A .
[0138] FIG. 10 shows schematically a brain area (denoted as A) shielded by a brain lesion (denoted as BL) in an area (denoted as B) surrounding the considered brain area (A).
DETAILED DESCRIPTION
[0139] FIG. 1A shows a transversal slice of a FLAIR-MR image without delineation of subcortical hyperintensities. Such transversal slices are known from prior art. FIG. 1B shows a transversal slice of a FLAIR-MR image with delineation of subcortical hyperintensities. In this Figure, a large confluent lesion can be well distinguished from a small spherical lesion.
[0140] A delineation as shown in FIG. 1B is used in a method according to the first exemplary embodiment explained in the following. FIGS. 2A to 6 will be explained with respect to this first exemplary embodiment. FIGS. 7A to 10 will be explained with respect to a second exemplary embodiment.
First Exemplary Embodiment: Calculation of a Weighted Confluency Sum Score (WCSS)
[0141] The exemplary embodiment relates to a (computer) system for fully automatic determination of a weighted confluency sum score (WCSS). This system utilizes magnetic resonance (MR) image data of the human brain. It starts with the automatic detection of all brain lesions in the MR image and accurate delineation of their outer contours. An exemplary result is shown in FIG. 1B . The system implements an algorithm for automatic detection of FLAIR-hyperintense white-matter lesions which has been proposed by Schmidt and co-workers for application in with multiple sclerosis [3].
[0142] This Schmidt algorithm generates a three-dimensional hyperintensity map which is then binarized. The binarized hyperintensity map is then clustered into separate hyperintensity lesions using the routine spm_bwlabel from the Statistical Parametric Software package (version SPM8, http://www.fil.ion.ucl.ac.uk/spm/). This routine labels connected components on the basis of a connectivity criterion to be specified. Six adjacent voxels (on the surface) have been defined here as connectivity criterion.
[0143] Then the system computes the confluency for each brain lesion according to formula (II)
[0000]
confluency
i
=
1
36
·
π
·
surf
i
3
vol
i
2
3
-
1
,
(
II
)
[0144] Surface and volume of the hyperintensity lesion are computed by counting of voxels as defined in the clustered hyperintensity map. This is computationally very efficient.
[0145] The weighting factor w i for a given hyperintensity lesion is defined according to its localization within the brain: w i =1, 2, 3, 4 if the lesion is located within periventricular white matter, deep white/grey matter, subcortical white matter, or within the brain stem, respectively. The assignment of the lesion to these four different regions is based on an anatomical map that has been previously created from tissue probability maps provided by SPM8. This anatomical map is depicted in FIG. 2A , wherein subcortical white matter is depicted in dark red, deep white/grey matter is depicted in green, periventricular white matter is depicted in orange and brainstem is depicted in blue. For a better anatomical orientation, FIG. 2B shows corresponding slices from a T1-weighted MR image. If a hyperintensity lesion is located in more than one of the regions, it is assigned the highest weighting factor of these lesions.
[0146] Finally, the weighted confluency sum score (WCSS) is computed according to formula (V)
[0000]
WCSS
=
∑
i
m
w
i
·
confluency
i
(
V
)
[0147] The individual parameters have the same meaning as in case of formula (I). The only difference between formula (I) and (V) is that in case of formula (V) m is used as number of the analyzed brain lesions. Thereby, m refers to the total number of hyperintensity lesions in the hyperintensity map consisting of at least 100 voxels.
[0148] The instantly described system has been successfully validated by the following experiments:
The algorithm proposed by Schmidt and co-workers for FLAIR-hyperintensity lesions in multiple sclerosis was successfully validated in 44 elderly patients (mean age 80 years) with unclear cognitive impairment from several wards for geriatric inpatients. As already explained above, there is no perfect sphere in MR images, but only ‘edgy’ approximations of a sphere composed of cubic voxels. Computer simulations of spheres composed of a varying number of cubic voxels showed that the resulting error in the confluency can be neglected for spheres composed of at least 100 voxels. The according results are shown in FIG. 3 . For spheres composed of at least 100 voxels, the confluency approaches zero, i.e. the value of an ideal sphere. Computer simulations were performed to show that the confluency according to formula (II) indeed is a useful measure of confluency of brain lesions. Specifically, 6 spherical lesions of 10 mm radius each and one cuboid simulating the confluency of the 6 spheres to one single contiguous lesion were analyzed. The results are depicted in FIGS. 4A and 4B . The calculated WCSS was almost zero for the pattern consisting of the 6 spherical lesions, whereas it was only 0.74 for the cuboid (all weighting factors were set to 1). When the number of spherical lesions that confluenced to a cuboid was increased, the WCSS of the cuboid showed a continuous increase. The according results can be seen in FIG. 5 showing that the confluency score of a cuboid increases continuously with its length, i.e. the number of spherical lesions that confluenced to the cuboid. The WCSS of the pattern of spherical lesions remained almost zero, independent on the number of spherical lesions (all weighting factors were set to 1). In a clinical evaluation, the area under a receiver-operating characteristic curve for differentiation between patients with vascular cognitive decline and patients without relevant cerebrovascular disease by the WCSS was 0.830. This is shown in FIG. 6 . This clearly shows that the WCSS is clinically useful.
Second Exemplary Embodiment: Calculation of a Percent Shielding by White Matter Hyperintensities (SbWMH)
[0154] Patho-physiological changes in the brain caused by neurodegenerative diseases such as Alzheimer's disease include alterations of brain activity (synaptic dysfunction). Positron emission tomography of the brain with the glucose analog F-18-fluorodeoxyglucose (FDG PET) provides biomarkers for (synaptic) function and dysfunction, as depicted in FIGS. 7A and 7B .
[0155] FIG. 7A shows FDG PET images of the brain in a patient with Alzheimer's disease. These images show a reduction of brain activity compared to a healthy subject (cf. FIG. 7B ) in most brain regions except visual and motor cortex, subcortical brain structures and the cerebellum. The reduction is most pronounced in posterior cingulum/precuneus area and the parietotemporal cortex (indicated by arrows). This pattern is typical for Alzheimer's disease. The reduction of brain activity is mainly caused by reduced synaptic activity. Although there is some loss of brain tissue (atrophy) in Alzheimer's disease, its impact on brain FDG PET is rather small, at least at early stages of the disease. In case of strong atrophy, the effect on FDG PET can be taken into account by partial volume correction.
[0156] In old patients, however, the detection of synaptic dysfunction associated with neurodegenerative disease is complicated by the high rate of vascular co-morbidity, for example infarcts of the brain of varying size. This is depicted in FIGS. 8A and 8B . FIG. 8A shows brain FDG PET images in a patient who was suspected to have Alzheimer's disease. The pattern of reduction in the PET indeed looks rather similar to the typical pattern in Alzheimer's disease (cf. FIG. 7A ). However, inspection of the MRI of the same patient (depicted in FIG. 8B ) reveals several infarcts and strong white matter disease (indicated by arrows). This vascular pathology fully explains the abnormal findings in the FDG PET. Therefore, there is no indication of Alzheimer's disease in this patient. The patient has vascular cognitive decline.
[0157] It is evident that there is no FDG uptake in infarcted tissue (scar). Whether or not a reduction of FDG uptake is the direct consequence of an infarct can be tested rather easily by coregistering T1- and/or T2-weigthed MRI (in which most infarcts are clearly displayed) to the FDG PET. However, not only infarcts but also impairment of axonal connections can cause reduced synaptic activity in both neighboring and distant grey matter regions, due to interruption of axonal tracts to this region.
[0158] Since white matter hyperintensities are to be considered as specific brain lesions, the novel biomarker SbWMH is an embodiment of the biomarker SbBL (shielding by brain lesions). It is a marker of impairment of axonal connections in form of a percent shielding of cortical brain regions by white matter hyperintensities.
[0159] A processing pipeline for fully automated computation and display of SbWMH has been implemented as a MATLAB script. For some processing steps, tools from the statistical parametric mapping software package are used (version SPM8). The pipeline comprises the following steps.
[0000] Extraction of White Matter Hyperintensities from Structural MRI
[0160] The “Lesion Segmentation Toolbox”, a freely-available add-on to SPM8, is used to extract WMHs from the patient's structural MRI. The toolbox requires a high-resolution T1-weighted MRI and a FLAIR-MRI as input. The output is a binary lesion map delineating WMHs in the patient's native space.
Co-Registration and Spatial Normalization of Lesion Map and FDG PET
[0161] SPM's co-register tool is used to register the lesion map with the FDG PET. SPM's normalize tool is used to transform co-registered images into the anatomical space of the Montreal Neurological Institute (MNI).
Generation of Hypometabolism Map
[0162] A (homoscedastic) t-test for two independent samples is used to compare the patient's normalized FDG PET to the normalized FDG PETs of a database of aged-matched healthy controls. The global FDG-uptake is used as reference value for intensity scaling prior to the statistical test. Reduced scaled FDG-uptake is defined as “hypometabolism” if p≦0.001. This results in a parametric map of hypometabolism. Such a hypometabolism map is shown in FIG. 9A depicting a parametric hypometabolism map (blue blobs) overlaid to the patient's FDG-PET.
Voxel-Wise Computation of SbWMH
[0163] The SbWMH is computed for each hypometabolic voxel as the fraction of neighboring white matter voxels affected by WMH ( FIG. 10 ). The 50 ml white matter voxels closest to the hypometabolic voxel are used as white matter “neighborhood”. White matter is defined by a binary mask that has been generated from the a priori tissue probability maps used for WMH lesion segmentation. The SbWMH values are saved to a 3-dimensional parametric map.
Display
[0164] The slover tool as implemented in SPM8 is used to display the SbWMH map (as “blobs” with “jet” colortable) together with the WMH lesion mask (as contours) superimposed to the patient's FDG PET in MNI space. An according map is shown in FIG. 9B depicting a parametric SbWMH map (jet-colored blobs) and WMH lesion map (red contours) overlaid to the FDG PET. The SbWMH values are quantitative: SbWMH=50 means that as much as 50% of the closest 50 ml white matter voxels are affected by WMH. As a consequence, the hypometabolism in this voxel most likely is caused by neighboring WMH, i.e. the hypometabolism is due to cerebrovascular disease, whereas no indication of neurodegenerative disease could be found.
[0165] In the example depicted in FIGS. 9A and 9B , the hypometabolism in the left lateral frontal cortex, the left parietotemporal cortex and in the precuneus can be explained by WMH (green arrows). The hypometabolism in the medial frontal cortex most likely is not caused by WMH, it rather might be an unspecific effect of old age (red arrow). The patient most likely does not suffer from Alzheimer's disease (AD), although the pattern of hypometabolism is similar to the typical AD pattern. Thus, in this case, the SbWMH map reduces the risk of misinterpretation the structural alterations of the brain as AD.
[0166] The basic idea underlying the percent shielding by brain lesions is illustrated in FIG. 10 . The percent shielding by brain lesions of a brain area A is computed as the percentage of image voxels or image pixels belonging to a brain lesion BL in a predefined volume or area B surrounding the considered brain area A. There can be more than one brain lesion BL in the volume or area B all of which contribute to the percent shielding of A.
LIST OF REFERENCES CITED IN THE PRECEDING SECTIONS
[0000]
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3. Schmidt, P., et al., An automated tool for detection of FLAIR - hyperintense white - matter lesions in Multiple Sclerosis . Neuroimage, 2012. 59(4): p. 3774-83.
4. Kapeller, P., et al., Visual rating of age - related white matter changes on magnetic resonance imaging: scale comparison, interrater agreement, and correlations with quantitative measurements . Stroke, 2003. 34(2): p. 441-5.
5. Prins, N. D., et al., Measuring progression of cerebral white matter lesions on MRI: visual rating and volumetrics . Neurology, 2004. 62(9): p. 1533-9.
6. van den Heuvel, D. M., et al., Measuring longitudinal white matter changes: comparison of a visual rating scale with a volumetric measurement . AJNR Am J Neuroradiol, 2006. 27(4): p. 875-8.
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15. Glodzik L, Kuceyeski A, Rusinek H, Tsui W, Mosconi L, Li Y, Osorio R S, Williams S, Randall C, Spector N, McHugh P, Murray J, Pirraglia E, Vallabhajosula S, Raj A, de Leon M J. Reduced glucose uptake and Aβ in brain regions with hyperintensities in connected white matter. Neuroimage. 2014 Oct. 15; 100:684-91
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The invention relates to novel imaging-based biomarkers for characterizing the structure or function of a human or animal brain. These biomarkers can be a weighted confluency sum score (WCSS) or a percent shielding by brain lesions (SbBL). Methods implementing these biomarkers are also disclosed.
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This is a division of application Ser. No. 235,427 filed Feb. 17, 1981.
BACKGROUND OF THE INVENTION
The present invention relates to an optical disk for optically writing and reading information and to a method for manufacturing the same.
An optical disk is known in which information is written by a laser beam modulated by the information, and the information is thereafter photoelectrically read by a laser beam.
In this type of optical disk, an optical recording layer of metal or photosensitive dye is covered on a substrate of glass or plastic whose surface is finished as an optical plane. As shown in FIG. 1, information is written on this optical disk 1 by rotating it in the direction shown by the arrow while irradiating an information-modulated laser beam L on the surface of the optical disk 1 with a lens 2 and moving a reading/writing head 3 in the direction of the arrow. This device incorporates a high precision tracking control mechanism for indirectly forming tracks to define the rotation of the optical disk 1 and the travelling path of the reading/writing head 3, since optical disk 1 does not have any guiding tracks. However, such a control mechanism tends to be mechanically complex and costly.
In order to more easily perform tracking for writing, an optical disk 4 has been proposed according to which, as shown in FIG. 2, a guiding groove 6 having a width of 0.6 μm and a depth of 1/8 of the wavelength (λ) of the laser beam L is formed on a substrate 5 at a track pitch of 1.67 μm, and an optical recording layer 7 is coated on the surface of this substrate. Such an optical disk is known, for example, from K. Bulthuis, et al, "Ten billion bits on a disk", IEEE, spectrum, Aug. p.26, 1979. When this grooved optical disk 4 and the planar optical disk 1 described above are compared the laser beam L which is focussed by the lens 2 and irradiated as a spot of diameter "d" on the optical disk 1 is reflected by the surface of the optical disk 1 and returns to the lens 2, as shown in FIG. 3. The power intensity "I" at the surface of the lens 2 of this reflected light generally has single-peaked power intensity distribution of I(γ). This reflected light catches I(γ)NA as defined by the effective aperture NA of the lens 2 and is guided to a photodetector. With the planar optical disk 1, since I(γ) is constant at any position of its surface, information cannot be recorded on the optical disk 1 at a desired track pitch unless the rotation of the optical disk 1 and the feeding of the lens 2 in the radial direction of the disk are correctly programmed in advance for indirect control.
On the contrary, with the grooved optical disk 4 shown in FIG. 2, the phase of the light reflected to the center of the surface of the lens 2 from the bottom surface of the guiding groove 6 having a depth of 1/8 of the wavelength of the laser beam lags that of the light reflected from the periphery of the guiding groove 6 by 1/4 wavelength. Thus, the reflected light rays caught at the center of the lens interfere with each other so that the power intensity is reduced. The total reflected light is diverged by the diffraction by the guiding groove 6 and is widely distributed over the surface of the lens 2. Thus, the power intensity distribution of the reflected light on the surface of the lens 2 becomes that as shown in FIG. 4. When the center of the irradiating spot of the laser beam L is aligned with the center of the guiding groove 6, the distribution becomes a symmetrical reflected light distribution of I'(γ) wherein the power intensity at the center of the lens 2 is low. When the center of the spot is deviated from the guiding groove 6, the distribution becomes the distribution I(γ) with maximum central power intensity. Thus, when variations in the power intensity and the distribution of the reflected light incident in NA of the lens 2 are converted into electrical signals by the photodetector disposed behind the lens 2, tracking may be easily performed so that the spot center of the laser beam L from the reading/writing head 3 is constantly aligned with the center of the guiding groove 6.
This guiding groove 6 is conventionally formed by photoetching methods utilizing a laser beam. However, as has already been described, it is very difficult to form, uniformly and with precision, guiding grooves of fine width and depth. This factor has significantly increased the cost of optical disks.
SUMMARY OF THE INVENTION
The present invention overcomes these problems of the prior art and, as its object, provides an optical disk according to which tracking control is easy, the manufacture is also easy, and the manufacturing cost may lowered. Another object of the present invention is to provide an optical disk having a guiding track such that the width of the guiding track is extremely small and the guiding track does not interfere with the high density of the recorded information, and a manufacturing method for the same.
The present invention thus provides an optical disk having an optical recording layer which is capable of having information written thereon by irradiating a focussed laser beam modulated by the information and also capable of reading the information characterized in that a protruding or recessed spiral track is formed on a substrate in relief with a desired pitch and a width of less than half the wavelength of the laser beam as a guiding track, an optical recording layer being located on the substrate.
The present invention further provides an optical disk characterized in that two substrates with said guiding tracks are superposed on each other with a spacer interposed therebetween and with their optical recording layers facing each other.
The present invention further provides a method for manufacturing an optical disk having an optical recording layer which is capable of having information written thereon by irradiating a focussed laser beam modulated by the information and also capable of reading the information, characterized by forming a spiral recessed track at a desired pitch on an original disk with a processing stylus having a pointed end, coating a metal layer on the original disk, peeling the metal layer to provide a recess in relief mold, forming a substrate having a recessed track using this mold as the original, and coating an optical recording layer on the surface of the substrate.
The present invention further provides a method for manufacturing an optical disk having an optical recording layer which is capable of having information written thereon by irradiating a focussed laser beam modulated by the information and also capable of reading the information, characterized by forming a spiral recessed track at a desired pitch on an original disk with a processing stylus having a pointed end, coating a metal layer on the original disk, forming a second original disk with a protruding track by peeling the metal layer, forming a recessed relief mold by coating a metal layer on the second original disk and peeling it off, casting a synthetic resin layer on this mold, forming a substrate having a protruding track by inverting the recessed track by peeling the synthetic resin layer, and coating an optical recording layer on the surface of the substrate.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic view illustrating the construction of a conventional planar optical disk and its writing and reading system;
FIG. 2 is an enlarged sectional view of a conventional optical disk with a tracking groove;
FIG. 3 is a view illustrating the reflecting condition of a laser beam in the conventional optical disk;
FIG. 4 is a view illustrating the reflecting condition of a laser beam in the conventional optical disk with a tracking groove;
FIGS. 5 and 6(A) are a sectional view and a perspective view for explaining the method according to the present invention;
FIG. 6(B) is a sectional view of an optical disk of the present invention;
FIGS. 7(A) to 7(B) are sectional views of a method for manufacturing the optical disk according to the second embodiment of the present invention;
FIGS. 8(A) to 8(E) are sectional views illustrating the method for manufacturing the optical disk according to the third embodiment of the present invention;
FIG. 9 is a view illustrating the reflecting condition of the laser beam in the first embodiment;
FIG. 10 is a view illustrating the reflecting condition of the laser beam in the third embodiment;
FIG. 11 is a sectional view of the optical disk according to the fourth embodiment; and
FIG. 12 is a sectional view of the optical disk according to a further embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
The present invention will now be described with reference to its examples shown in the attached drawings. FIGS. 5 and 6 (A and B) show the first embodiment of the device which uses a diode laser beam of about 0.82 μm wavelength. Reference numeral 11 denotes a disk-shaped substrate made of glass. When a processing stylus 12 of a hard material such as diamond whose end 12a is semispherical and 0.3 μm in diameter is pressed with a load of about 0.1 g on the surface of the substrate 11 as shown in FIG. 5, recesses 13 of a depth of about 0.2 μm are formed by plastic deformation, conforming to the shape of the end 12a of the processing stylus 12. Then, as shown in FIG. 6(A), when the substrate 11 is rotated in the direction shown by the arrow and the stylus 12 is displaced in the radial direction of the substrate 11 (the direction shown by the arrow), a spiral recessed track 14 is formed in the surface of the substrate 11. An optical disk 16 is formed by coating an optical recording layer 15 on the surface of the substrate 11 in which this recessed track 14 is formed. (FIG. 6(B))
FIGS. 7(A) to 7(E) show the second embodiment of the present invention and illustrates the method for manufacturing the optical disk. Reference numeral 17 in FIG. 7(A) denotes an original disk of a glass material on the surface of which are formed spiral recessed tracks 18 by the processing stylus 12 as in the case of the first embodiment. When a metal layer 19 is coated on the surface of the original disk 17 as shown in FIG. 7(B) and the metal layer 19 is peeled off the original disk 17, a track relief mold 21 is formed having protruding tracks 20 of an inverted pattern with respect to the recessed tracks 18. When this track relief mold 21 is pressed on a disk-shaped substrate 22 of a synthetic resin material as shown in FIG. 7(D), recessed tracks 23 with an inverted pattern of the protruding tracks 20 are formed on the surface of the substrate 22. An optical disk 25 is manufactured by coating an optical recording layer 24 on the surface of the substrate 22, as in the case of the first embodiment.
The original disk 17 may be made of materials other than glass, such as metals like copper and nickel, or plastics.
FIGS. 8(A) to 8(E) show the method for manufacturing an optical disk according to the third embodiment of the present invention.
First, in a manner similar to the first and second embodiments and the processes shown in FIGS. 7(A) to 7(C), the spiral recessed tracks 18 are formed by the processing stylus 12 on the surface of the original disk 17 of the same material as used in the second embodiment described above. After coating a metal layer similar to that formed in the second embodiment on the original disk 17, this metal layer is peeled off to provide a second original disk 21' having protruding tracks 20' as shown in FIG. 8(A). After coating a metal layer on this second original disk 21', this metal layer was peeled off to provide a track relief mold 26 having recessed tracks 27 as shown in FIG. 8(B). A synthetic resin layer 28 is cast onto relief mold 26, as shown in FIG. 8(C). When the synthetic resin layer 28 is thereafter peeled off the track relief mold 26, a substrate 30 having protruding tracks 29 in a pattern inverted with respect to the recessed tracks 27 is formed as shown in FIG. 8(D). Then, an optical disk 32 having the protruding tracks 29 may be manufactured by coating an optical recording layer 31 on the surface of the substrate 30 as shown in FIG. 8(E). Once manufactured, the track relief mold 26 may be repeatedly used so that a number of optical disks may be manufactured with a single track relief mold 26.
The optical recording layers 15, 24 and 31 formed in the first to third embodiments of the present invention may be turned into extremely stable optical recordiing layers by vacuum depositing tellurium films on the substrates 11, 22 and 30 and forcibly oxidizing the surface of these films using ultraviolet rays.
As shown in the first and second embodiments, the width of the recessed tracks 14 and 23 of the optical disks 16 and 25 is about 0.3 μm. Therefore, this width is sufficiently narrower than the wavelength of the laser beam used in the optical writing and reading system of this type (0.62 μm with a He-Ne laser, and 0.82 μm with an AlGaAs diode laser). Furthermore, since the bottoms of the recessed tracks 14 and 23 are spherically curved, the laser beam incident on the recessed tracks 14 and 23 is divergently reflected. That is, the tracks function to reflect the incident laser beam to distribute it more widely than the effective aperture of the lens.
Accordingly, taking the optical disk 16 as an example as shown in FIG. 9, when the optical disk 16 is irradiated with the laser beam L with the spot diameter d, the light incident within the recessed track 14 is divergently reflected up to a maximum angle of θg by the diffraction of the light upon reflection at the curved surface. The light reflected from the periphery of the recessed track 14 is distributed within the range of θe. For this reason, the power intensity of light reflected at the surface of lens 33 changes from I(γ), when the recessed track 14 is not present, to I"(γ), and the amount of reflected light which is incident on the lens 33 having effective aperture of about 0.5 which is generally used is minimized when the center of the spot "d" in diameter of the laser beam is aligned with the central line of the recessed track. When the center of the spot of diameter "d" of the incident laser beam "L" is deviated to the right or left of the central line of the recessed track 14, the amount of reflected light incident on the lens increases and its distribution I"(γ) at the surface of the lens 33 becomes assymetrical so that the intensity is weak in the direction opposite to its deviation. In this manner, with the optical disk 16 having the recessed track 14 with a curved surface at the bottom, it is possible to monitor whether the center of the spot of the irradiated laser beam L is on the central line of the recessed track 14 by measuring with a photodetector the amount of reflected light incident on the lens 33 and its power intensity distribution. Thus, tracking control may be performed such that the center of the spot of the laser beam "L" is constantly aligned with the central line of the recessed track 14 of the optical disk 16.
The wavelength of the laser beam L which is generally used is about 0.6 to 0.83 μm and the spot diameter "d" is about 1.5 μm. Therefore, the ratio of the amount of light which is scatteringly reflected by the recessed track 14 formed in the optical disk 16 is maximized when the center of the spot of the laser beam is aligned with the central line of the recessed track. It is about 8.5% when the width of the recessed track 14 is 0.1 μm, about 25% when the width is 0.3 μm, and about 40% when the width is 0.5 μm. The width of the recessed track 14 formed on the optical disk 16 may be about half the wavelength of the laser beam used, that is, about 0.41 μm or less. When the width of the recessed track 14 is wider than this, adverse effects are considerably increased. For example, the amount of the codes of the information to be recorded with the 1.5 μm spot diameter is decreased. With the optical disk 32 having the protruding track 29 as in the third embodiment described above, as shown in FIG. 10, the laser beam L with the spot diameter "d" is divergently reflected by the curved surface reflection of the protruding track 29 and the diffraction of light. Since this embodiment has similar effects as the first and second embodiments, the same reference numerals are given and the detailed description will be omitted.
FIG. 11 shows the fourth embodiment of the present invention. Reference numerals 34 and 35 denote two disk bodies obtained in a manner similar to that in the second embodiment. These disk bodies 34 and 35 are superposed on each other in such a manner that their surfaces have recessed tracks 36 and 37 which face each other, and spacers 38 and 39 about 2 mm in thickness are interposed between the disk bodies at their inner and outer peripheries. With this construction, the laser beam "L" may be irradiated from the rear surfaces of the disk bodies 34 and 35 for writing and reading. Furthermore, with this construction, optical recording layers 40 and 41 may be protected and the amount of information to be recorded may be increased, providing a double-faced optical disk.
The present invention thus provides an optical disk into which information may be written and from which such information may be read, wherein a spiral recessed or protruding track is formed on a substrate and an optical recording layer is coated thereon, so that any deviation of the center of the spot of the laser beam from the center of the protruding or recessed track may be detected. Using this spiral protruding or recessed track as a guideline, tracking control may be easily accomplished while irradiating the laser beam on the optical disk.
In accordance with the present invention, the recessed track, whose dimensions, particularly its depth, need not be precisely regulated, is formed by pressing a processing stylus on the surface of the substrate for plastic deformation; and the protruding track is formed by inverting the pattern of the recessed track. Thus, the optical disk may be manufactured with ease.
In accordance with the present invention, since the recessed or protruding track is formed with a hard processing stylus such as a diamond stylus, a narrow track (less than a half the wavelength of the laser beam) may be formed which has been heretofore impossible with the conventional photoetching method which utilizes the laser beam. Further, the process may be considerably simplified.
In the embodiments, the bottom surface or the protruding surface of the recessed or protruding track was curved. However, the present invention is not limited to this particular construction. For example, the bottom surface or the protruding surface of the recessed or protruding track may be V-shaped or inverted V-shaped for obtaining the same effects. This shape may be easily changed by suitably selecting the shape of the pointed end of the processing stylus. FIG. 12 shows the case wherein a V-shaped groove 14' is formed on the surface of the substrate 11 by a processing stylus having a V-shaped front end, and an optical recording layer 15' is coated thereover.
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In an optical disk having an optical recording layer which is capable of having information thereon using a laser beam with information superposed by modulation there is formed a spiral protruding or recessed track having a width equal to about half or less of the wavelength of a laser beam to be used, this track being utilized as the guiding track of the laser beam. A method for manufacturing such an optical disk is also disclosed according to which a recessed track for tracking is formed by plastic deformation of the upper surface of an original disk with a hard processing stylus such as a diamond stylus. The original disk thus produced is utilized for forming an optical recording disk having a protruding or recessed guiding track.
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TECHNICAL FIELD
This application is a continuation of application Ser. No. 10/888,822, filed Jul. 9, 2004 now U.S. Pat. No. 7,258,802. The invention relates to a system for controlling the amount of organisms in process water used to form binder coated glass fibers. Reducing or eliminating the organisms present in the process water serves at least three critical functions. First, the organisms in the process water may pose health risks to plant personnel and others who may come into contact with the bacteria. Reducing the level of organisms present reduces these health risks. Second, some organisms may corrode process piping and equipment, requiring costly repairs and replacement, and hampering the ability to efficiently operate the process. Reducing or eliminating the level or organisms minimizes the risk of corrosion of piping and equipment. Third, growth or organisms may cause blockage in process lines, resulting in inefficient operation. Reducing the level of organisms also reduces blockage in process lines.
BACKGROUND OF THE INVENTION
Fiberglass binders have a variety of uses ranging from stiffening applications where the binder is applied to woven or non-woven fiberglass sheet goods and cured, producing a stiffer product; thermo-forming applications wherein the binder resin is applied to sheet or lofty fibrous product following which it is dried and optionally B-staged to form an intermediate but yet curable product; and to fully cured systems such as building insulation.
Fibrous glass insulation products generally comprise matted glass fibers bonded together by a cured thermoset polymeric material. Molten streams of glass are drawn into fibers of random lengths and blown into a forming chamber where they are randomly deposited as a mat onto a traveling conveyor. The fibers, while in transit in the forming chamber and while still hot from the drawing operation, are sprayed with an aqueous binder. A phenol-formaldehyde binder is currently used throughout the fibrous glass insulation industry. The residual heat from the glass fibers and the flow of air through the fibrous mat during the forming operation are generally sufficient to volatilize the majority to all of the water from the binder, thereby leaving the remaining components of the binder on the fibers as a viscous or semi-viscous high solids liquid. The coated fibrous mat is transferred to a curing oven where heated air, for example, is blown through the mat to cure the binder and rigidly bond the glass fibers together.
Fiberglass binders used in the present sense should not be confused with matrix resins which are an entirely different and non-analogous field of art. While sometimes termed “binders,” matrix resins act to fill the entire interstitial space between fibers, resulting in a dense, fiber reinforced product where the matrix must translate the fiber strength properties to the composite, whereas “binder resins” as used herein are not space-filling, but rather coat only the fibers, and particularly the junctions of fibers. Fiberglass binders also cannot be equated with paper or wood product “binders” where the adhesive properties are tailored to the chemical nature of the cellulosic substrates. Many such resins, e.g. resorcinol/formaldehyde resins, are not suitable for use as fiberglass binders. One skilled in the art of fiberglass binders would not look to cellulosic binders to solve any of the known problems associated with fiberglass binders.
Binders useful in fiberglass insulation products generally require a low viscosity in the uncured state, yet have characteristics to form a rigid thermoset polymeric mat for the glass fibers when cured. A low binder viscosity in the uncured state is required to allow the mat to be sized correctly. Also, viscous binders tend to be tacky or sticky and hence they lead to accumulation of fiber on the forming chamber walls. This accumulated fiber may later fall onto the mat causing dense areas and product problems.
From among the many thermosetting polymers, numerous candidates for suitable thermosetting fiberglass binder resins exist. However, binder-coated fiberglass products are often of the commodity type. Thus, cost becomes a driving factor, generally ruling out such resins as thermosetting polyurethanes, epoxies, and others. Due to their excellent cost/performance ratio, the resins of choice in the past have been phenol/formaldehyde resins. Phenol/formaldehyde resins can be economically produced, and can be extended with urea prior to use as a binder in many applications. Such urea-extended phenol/formaldehyde binders have been the mainstay of the fiberglass insulation industry for years.
Over the past several decades, however, minimization of volatile organic compound emissions (VOCs) both on the part of the industry desiring to provide a cleaner environment, as well as by Federal regulation, has led to extensive investigations into not only reducing emissions from the current formaldehyde-based binders, but also into candidate replacement binders. For example, subtle changes in the ratios of phenol to formaldehyde in the preparation of the basic phenol/formaldehyde resole resins, changes in catalysts, and addition of different and multiple formaldehyde scavengers, have resulted in considerable improvement in emissions from phenol/formaldehyde binders as compared to the binders previously used. However, with more stringent federal regulations, more attention has been paid to alternative binder systems which are free from formaldehyde.
One particularly useful formaldehyde-free binder system employs a binder comprising a polycarboxy polymer and a polyol. As used herein, formaldehyde-free refers to resins in compositions that are substantially free of formaldehyde and/or do not liberate substantial amounts of formaldehyde as a result of drying or curing. Formaldehyde-free resins do not emit appreciable levels of formaldehyde during the insulation manufacturing process and do not emit formaldehyde under normal service conditions. Use of this binder system in conjunction with a catalyst, such as an alkaline metal salt of a phosphorous-containing organic acid, results in glass fiber products that exhibit excellent recovery and rigidity properties.
An inherent benefit of phenolic-based resins is the natural biocide characteristics of formaldehyde. As used herein, the term “biocide” refers to agents which destroy or kill organisms as well as materially inhibit the growth of organisms. Formaldehyde-free binder systems, such as a system comprising a polycarboxy and a polyol, do not have such a natural biocide characteristic. Thus, use of formaldehyde-free binders results in process water systems becoming overwhelmed with growing organisms. As a result of high levels of harmful organisms in the process water, plant personnel are exposed to a risk of adverse health effects. In addition, some organisms may cause corrosion of process piping and equipment, requiring costly repairs and replacement and hampering the ability to efficiently operate the process. Also, a high level of organisms may cause blockage of process lines. Thus, preventative measures need to be taken to significantly reduce or eliminate entirely the organisms in the process water.
BRIEF SUMMARY OF THE INVENTION
Formaldehyde-free binders used to coat glass fiber products are typically sprayed onto the product in the form of an aqueous slurry. After the product is dried, residual water is collected in a collection box and sent to a process water reservoir, where it remains until recycled back into the process. Harmful organisms may form and grow in the process water reservoir or elsewhere in the process water system, posing health risks to plant personnel, causing corrosion of process piping and equipment and clogging process lines.
Bacteria are among the most harmful organisms that may form in a process. Generally, two types of bacteria form in the process water, aerobic and anaerobic bacteria. Anaerobic bacteria, the more harmful of the two, thrive in anaerobic (little or no oxygen) conditions. They must have anaerobic conditions which may be associated with microsites in an otherwise oxidized system. Among the anaerobic bacteria that often grow in recycle process water are sulfate-reducing bacteria. Sulfate reducing bacteria often find small anaerobic pockets under deposits or in accumulated debris in process waters. They use sulfate as their last electron acceptor and convert it to hydrogen sulfide, a material notorious for its corrosivity to virtually all metals. The production of hydrogen sulfide and resulting corrosion is particularly harmful to process piping and equipment.
“Aerobic bacteria” may also form in the process water container. Aerobic bacteria can survive in the presence of oxygen. While not as harmful as anaerobic bacteria, aerobic bacteria may nonetheless cause health problems for those plant personnel that come into contact with it, as well as cause some corrosion and blockage of process piping and equipment.
While bacteria are among the most common and most harmful organisms that form in process water, other organisms may also form and cause various problems.
Adding an effective amount of one or more biocides to the process water controls the growth of organisms in process water used to form binder coated fibers without interfering with the binder composition or corroding process piping. The present invention provides a means for controlling the growth of organisms in process water used to form binder coated fibers. The invention is a method for controlling the growth of organisms in the process water by adding a biocide to the process water. Alternatively, radiation can be used to prevent or control the growth of organisms.
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 which form the subject of the claims of the invention. It should be appreciated that the conception and specific embodiment 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 that such equivalent constructions do not depart from the invention as set forth in the appended claims. The novel features which are believed to be characteristic of the invention, both as to its organization and method of operation, together with further objects and advantages will be better understood from the following description when considered in connection with the accompanying figures. It is to be expressly understood, however, that each of the figures is provided for the purpose of illustration and description only and is not intended as a definition of the limits of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
For a more complete understanding of the present invention, reference is now made to the following descriptions taken in conjunction with the accompanying drawing, in which:
FIG. 1 is a schematic of the process, showing the addition of one biocide to a recycle water slip stream.
FIG. 2 is a schematic of the process, showing the sequential addition of two biocides to a recycle water slip stream.
DETAILED DESCRIPTION OF THE INVENTION
The invention relates to a method for reducing or eliminating organisms in the system used to recycle process water employed in the production of glass fiber product. The method is particularly useful for systems that produce formaldehyde-free binders containing fiberglass products.
Among the formaldehyde-free binders described above are typically polycarboxy polymers such as acrylic resins, although any formaldehyde-free resin or binder compositions are within the scope of this invention. Formaldehyde-free resins generally have a molecular weight of less than about 10,000, preferably less than about 5,000, most preferably less than about 3,000 with about 2,000 being advantageous.
The polycarboxy polymer used in the binder of the present invention comprises an organic polymer or oligomer containing more than one pendant carboxy group. The polycarboxy polymer may be a homopolymer or copolymer prepared from unsaturated carboxylic acids including, but not necessarily limited to, acrylic acid, methacrylic acid, crotonic acid, isocrotonic acid, maleic acid, cinnamic acid, 2-methylmaleic acid, itaconic acid, 2-methylitaeonic acid, alpha., .beta.-methyleneglutaric acid, and the like. Alternatively, the polycarboxy polymer may be prepared from unsaturated anhydrides including, but not necessarily limited to, maleic anhydride, methacrylic anhydride, and the like, as well as mixtures thereof. Methods for polymerizing these acids and anhydrides are well known in the chemical art.
The formaldehyde-free curable aqueous binder composition of the present invention also contains a polyol containing at least two hydroxyl groups. The polyol must be sufficiently nonvolatile such that it will remain substantially available for reaction with the polyacid in the composition during heating and curing operations. The polyol may be a compound with a molecular weight less than about 1,000 and having at least two hydroxyl groups such as, for example, ethylene glycol, glycerol, pentaerythritol, trimethylol propane, sorbitol, sucrose, glucose, resorcinol, catechol, pyrogallol, glycollated ureas, 1,4-cyclohexane diol, diethanolamine, triethanolamine, and certain reactive polyols such as, for example, beta.-hydroxyalkylamides such as, for example, bis[N,N-di(∃-hydroxyethyl)]adipamide, as may be prepared according to the teachings of U.S. Pat. No. 4,076,917, hereby incorporated herein by reference, or it may be an additional polymer containing at least two hydroxyl groups such as, for example, polyvinyl alcohol, partially hydrolyzed polyvinyl acetate, and homopolymers or copolymers of hydroxyethyl(meth)acrylate, hydroxypropyl(meth)acrylate, and the like. The most preferred polyol for the purposes of the present invention is triethanolamine. (TEA)
The ratio of the number of equivalents of carboxy, anhydride, or salts thereof of the polyacid to the number of equivalents of hydroxyl in the polyol is from about 1/0.01 to about 1/3. An excess of equivalents of carboxy, anhydride, or salts thereof of the polyacid to the equivalents of hydroxyl in the polyol is preferred. The more preferred ratio of the number of equivalents of carboxy, anhydride, or salts thereof to the number of equivalents of hydroxyl in the polyol is from about 1/0.4 to about 1/1. The most preferred ratio of the number of equivalents of carboxy, anhydride, or salts thereof in the polyacid to the number of equivalents of hydroxyl in the polyol is from about 1/0.6 to about 1/0.8, and most preferably from 1/0.65 to 1/0.75. A low ratio, approaching 0.7/1, has been found to be of particular advantage in the present invention, when combined with a low molecular weight polycarboxy polymer and the low pH binder.
The formaldehyde-free curable aqueous binder composition of the present invention also contains a catalyst. Most preferably, the catalyst is a phosphorous-containing accelerator which may be a compound with a molecular weight less than about 1,000 such as, for example, an alkali metal polyphosphate, an alkali metal dihydrogen phosphate, a polyphosphoric acid, and an alkyl phosphinic acid or it may be an oligomer or polymer bearing phosphorous-containing groups such as, for example, addition polymers of acrylic and/or maleic acids formed in the presence of sodium hypophosphite, addition polymers prepared from ethylenically unsaturated monomers in the presence of phosphorous salt chain transfer agents or terminators, and addition polymers containing acid-functional monomer residues such as, for example, copolymerized phosphoethyl methacrylate, and like phosphonic acid esters, and copolymerized vinyl sulfonic acid monomers, and their salts. The phosphorous-containing accelerator may be used at a level of from about 1% to about 40%, by weight based on the combined weight of the polyacid and the polyol. Preferred is a level of phosphorous-containing accelerator of from about 2.5% to about 10%, by weight based on the combined weight of the polyacid and the polyol.
The binder resins used in the invention are usually supplied as an aqueous suspension containing about 48 to 53 Wt. % solids. The binder composition used in the invention is prepared by first further diluting the binder to create an aqueous binder composition.
Acid is then added to the aqueous binder composition to reduce the pH to less than about 3.5, preferably less than 3.0, more preferably less than 2.5. Low pH has been found to be important in ensuring proper application and curing of the binder composition.
The binder is then applied to the fiberglass in a manner well known to those skilled in the art. After the binder is applied, much of the water in the binder, also known as the process water, is removed and captured for reuse by means of a recycle system. In addition, the water used to wash residual binder from the production equipment is also added to the recycle system.
Harmful organisms can grow and live in the process water contained in the recycle system. This is especially true if the recycled process water is stored for some period of time before reuse. This can cause health problems for plant personnel and others who come into contact with the organisms. For example, legionella can grow in the storage tanks. Further, some types of organisms, particularly anaerobic sulfate-reducing bacteria, may cause corrosion of process piping and equipment. Preventative measures need to be taken to control or eliminate the growth of organisms in the process water.
The addition of an effective amount of a suitable biocide may reduce, kill or suppress the growth of harmful organisms in the process water system. Biocides useful in the practice of the invention include oxidants such as ozone, hydrogen peroxide, halogens (e.g. chlorine, bromine and iodine) and halogen-containing compounds. The halogen-containing compounds useful in the practice of the invention include sodium bromide, sodium hypochlorite, calcium hypochlorite, and iodine-containing compounds, with sodium bromide and sodium hypochlorite preferred. Penetrants can be used to improve the efficacy of some biocides such as glutaraldehyde, methylene bis thicyanate. Finally, other effective biocides will be readily apparent to those skilled in the art.
In addition to the use of chemical biocides, other methods can be used to treat the process water. For example, the process water can be exposed to radiation at sufficient intensity to kill organisms present in the water. Of the numerous radioactive treatments known to those skilled in the art, ultraviolet radiation is preferred.
The amounts and types of organisms that grow in the process water in turn depend on a variety of factors. The amount of biocide that must be added to be effective in practicing the invention depends on the amounts and types of organisms that grow in the process water, and the volume of the system being treated. For example, the type of binder used in the process and the amount of time the water is stored before being reused affect the amounts and types of organisms that form. Other factors that contribute to organisms forming in the process will be apparent to those skilled in the art.
In one embodiment using a liquid biocide, treatment rates may range from about a 1.6-gallon (6.05-liter) dose of biocide added once per day to about a 12-gallon (45.4-liter) dose of biocide added three times per week. More frequent treatment may also be employed where feasible; for example, a 1.8-gallon (6.8-liter) dose of biocide added about twenty-one times per week may be used. When treating the process with a solid form of biocide, a typical treatment amount is a continuous treatment of about 50 pounds (22.7 kilograms) per day. Although these amounts are typical, the amount required may vary significantly depending on several process characteristics. Necessary treatment amounts will be readily apparent to those skilled in the art.
A biocide may be introduced into the process in several ways. A preferred method is to pump or otherwise inject a biocide in liquid form into a slip stream taken off the main process water recycle stream. The slip stream is then sent back into the main recycle stream before being sent to a process water reservoir. A metering pump may be used to automatically control the amount of biocide injected into the slip stream depending on system needs.
Alternatively, a powder form of the biocide may be introduced anywhere in the recycle water system using any suitable means. Also, solid tablets may be dropped directly into the process water reservoir. If feasible, a biocide may even be bubbled into the recycle process water in gaseous form. Finally, in the case of radiation, the process water stream may be exposed to a focused beam of radiation for a sufficient period to ensure eradication of any organisms present. Other methods of introducing a biocide, well known to those skilled in the art, may be employed as well.
More than one biocide may be added to the process water, either by taking a slip stream off of the main recycle stream or by adding the biocides directly to the main recycle stream. One preferred method adds a liquid form of one biocide to a recycle slip stream, then adds another biocide to the recycle slip stream before combining the slip stream with the main recycle stream. However, any number of biocides may be added by any of the methods described above, or by any other suitable method.
As discussed above, the production of formaldehyde-free fiberglass products requires the use of sufficient amounts of process water. The water is extracted from the product just before the product is cured. This extracted process water is then recycled back into the process through the recycle system.
One embodiment of the invention is shown in FIG. 1 . The binder coated fibers 11 are gathered in a collection box 12 . Air is drawn through the collection box by one or more fans 13 which gather the glass fibers into a mat 14 . The air flow also forces residual water out of the fiberglass mat 14 , drying the collected fibers before they leave the collection box 12 . A recycle stream 15 containing the process water is then sent to a process water reservoir 16 , where it is stored until being recycled back into the process. Harmful bacteria may form in the process water reservoir 16 and elsewhere in the recycle system, raising health concerns for plant personnel and possibly corroding process piping and equipment when the water is recycled back into product makeup part of the process. As a result, a slip stream 17 is taken off of the recycle stream 15 and treated with one or more biocides. It is then sent back into the main recycle stream 18 and the combined stream 19 is sent to the process water reservoir 16 .
The biocide or combination of biocides used to treat the process water system should be effective against both anaerobic and aerobic bacteria, and particularly against harmful sulfate-reducing bacteria. A commonly used biocide is sodium bromide. Sodium bromide effectively kills both types of bacteria. Thus, it is a commonly used biocide for this type of water treatment. As shown in FIG. 1 , sodium bromide, for example, is stored in a storage vessel 20 and is injected into the recycle slip stream 17 periodically. A metering pump 21 may be utilized to effectively control the amount of sodium bromide added to the recycle system. The combined stream 22 is then rejoined with the main recycle stream 18 , and the resulting stream 19 is sent to the process water reservoir 16 .
An example of an effective sodium bromide treatment system is LiquiBrom 4000, by Houghton Chemical Corporation. LiquiBrom 4000 is a ready-to-use solution of sodium bromide. It provides a cost-effective way to treat industrial process waters using bromine chemistry. In practice, a wide range of factors can effect the required treatment, including condition of the recycle water, system halogen demand, treatment objectives, sensitive equipment locations, and sample point locations.
Sodium bromide is most effective when mixed in water and activated by a chlorine source (such as chlorine or sodium hypochlorite). As shown in FIG. 2 , sodium bromide is stored in a storage vessel 120 , and injected into a recycle water slip stream 117 . A metering pump 121 may be used to monitor and control the amount of sodium bromide added to the slip stream 117 . A chlorine compound such as sodium hypochlorite is then added to the resulting stream 122 . Again, the chlorine compound is stored in a storage vessel 123 , and a metering pump 124 may be utilized to control the amount of the chlorinated compound added to the process. The combined stream 125 of sodium bromide, the chlorinated compound and recycle water is then directed back into the main recycle stream 118 , and sent to a recycle water reservoir 116 . The numbers for each process stream or piece of equipment in FIG. 2 corresponds to the same stream or piece of equipment in FIG. 1 , except that in FIG. 2 a “1” has been added. For example, the recycle slip stream is numbered 17 in FIG. 1 . The same stream is numbered 117 in FIG. 2 .
Sodium bromide is just one example of a suitable biocide for treating the process water. Any effective biocide may be used. An effective biocide should kill or inhibit the growth of harmful aerobic and anaerobic bacteria. Further, it should not alter the composition of the binder, corrode process piping or equipment, or cause blockage in the process piping.
In addition to sodium bromide and other biocides, addition of one or more penetrants serves to such as gluteraldehyde, carbamates, and thiocyanates may improve the effectiveness of biocides. However, any substance that effectively reduces nutrients available to organisms in the process water without otherwise harming or hampering the process may be used.
Additionally, it is not necessary that any or all biocides be introduced into the recycle water system in liquid form as shown in FIGS. 1 and 2 . Solid biocide may also be introduced in powder or pellet form, if available. Solid biocide tablets may also be dropped directly into the process water reservoir for effective treatment. In addition, a biocide gas may be bubbled into the system to effectively reduce or eliminate the harmful bacteria and other organisms. The efficiency of one form relative to the others will depend largely on the amount and type of bacteria or organisms in the recycle water system, and the resulting treatment requirements. It is generally thought that addition of biocide in liquid form is most efficient in most situations.
Although the present invention and its advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the invention as defined by the appended claims. Moreover, the scope of the present application is not intended to be limited to the particular embodiments of the process, machine, manufacture, composition of matter, means, methods and steps described in the specification. As one will readily appreciate from the disclosure, processes, machines, manufacture, compositions of matter, means, methods, or steps, presently existing or later to be developed that perform substantially the same function or achieve substantially the same result as the corresponding embodiments described herein may be utilized. Accordingly, the appended claims are intended to include within their scope such processes, machines, manufacture, compositions of matter, means, methods, or steps.
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A system for reducing or preventing the growth of organisms in the process water used to coat glass fibers with a formaldehyde-free binder composition. One or more biocides is added to the process water that mitigates the growth of microbes in the water. The biocides are added in an amount sufficient to minimize growth of organisms without adversely affecting the application of the binder composition to the glass fibers.
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TECHNICAL FIELD
The present invention relates to syringes and, more particularly, to self-destroying or otherwise non-reusable disposable syringes.
BACKGROUND ART
Syringes are in common use today for hypodermic injection. Often these syringes are disposable syringes intended for only one use. However, these syringes are capable of repeated reuse if a user so desires. A serious problem today is that syringes are obtainable by intravenous drug addicts who repeatedly reuse and share the same syringe with other drug addicts without proper sterilization between each use. Hence, any blood-borne infectious disease that one such addict has is spread to those with whom he shares his syringes. This mechanism is thought to be a major cause of the current AIDS epidemic, as well as contributing to the spread of hepatitis, venereal disease, and other blood-borne diseases.
Recognizing this problem with the use of the injectible drugs, the present inventor has obtained U.S. Pat. No. 4,699,614, issued on Oct. 13, 1987. This patent described a non-reusable syringe having a barrel with an open end and a restricted end, a piston slidably positioned within the barrel and forming a liquid-tight seal with the interior of the barrel. A shaft is freely slidable within the barrel and extends beyond one end of the barrel. A connector engages the piston and the shaft and has a protrusion extending therefrom. A guide is formed on the shaft for receiving the protrusion of the connector. In generation, the connector is detachable from the shaft. In such invention, the connector comprises a collar holder fastened at one end of the piston, and a collar freely rotatable about the collar holder. The guide comprises a groove formed on the shaft which engages the protrusion from the connector. The guide causes the shaft to be disconnected from the piston following an injection of the liquid from the syringe.
After extensive use and experimentation with the present invention, it was found to be desirable to provide improvements to such syringe that could be manufactured and assembled less expensively, more easily, and with greater reliability. It was found that an inexpensive price of manufacture would allow the self-destructing syringes to be more widely available.
It is an object of the present invention to provide a non-reusable syringe that requires fewer parts than previous non-reusable syringes.
It is another object of the present invention to provide a non-reusable syringe that is capable of relatively simple manufacture at inexpensive prices.
It is another object of the present invention to provide a non-reusable syringe that is of inexpensive cost and is suitable for reliable widespread usage.
It is still a further object of the present invention to provide a non-reusable syringe that self-destructs following a single use, that avoids tampering, and deters the spread of fatal infectious diseases.
These and other objects and advantages of the present invention will become apparent from a reading of the attached specification and appended claims.
SUMMARY OF THE INVENTION
The present invention is a non-reusable syringe that comprises a barrel having one open end and one restricted end, a piston slidably positioned within the barrel and forming a liquid-tight seal within the interior of the barrel, a shaft freely slidable within the barrel and having one end extending beyond the barrel, a connector engaging the piston and the shaft and having two prongs extending therefrom, and two guides formed on the shaft and arranged so as to receive the prongs of the connector. The connector is detachable from the shaft. The connector is rotatably attached to the piston. The guides control the movement of the piston relative to the movement of the shaft and include means for causing the connector to detach from the shaft.
The connector is a short shaft with a arrowhead-shaped portion on one end that enters an orifice on the side of the piston facing the open end of the barrel. This connects the piston to the connector so that the connector is freely rotatable within the orifice of the piston. The shaft of the connector forks and has two prong ends at the end facing the open end of the barrel. Each of the prongs of this connector have an inwardly facing pin. Each of these pins engages one guide on the shaft. These pronged ends are manufactured to be springy such that they tend to come together at the pins when not engaged with the guides on the shaft. When sprung apart, the distance between the two prongs of the connector is greater than the outer diameter of the shaft, and the distance between the inner pins of the two prongs is less than the outer diameter of the shaft.
Each guide of the present invention comprises a groove formed in the outside surface of the shaft and arranged so as to receive a pin of the connector. The groove has a Z-shaped configuration. This groove has an open end at the end of the shaft adjacent the restricted end of the barrel. This groove has a closed end at the opposite end of this Z-shaped configuration. The groove comprises a first portion that extends from the open end linearly and longitudinally aligned with the shaft, a second portion extending at an acute angle from the end of the first portion and extending toward the end of the shaft adjacent the restricted end of the barrel, and a third portion extending at an acute angle from the end of the second portion toward the open end of the barrel. The first portion of the groove has a constant width. The second portion of the groove has a constantly increasing width between the end of the first portion and the beginning of the third portion. The third portion has a generally constant width. The third portion extends from the second portion at an angle diagonal to the axis of the shaft. This third portion has a cul-de-sac end opposite the second portion. This Z-shaped groove occurs on opposite sides of the shaft and is aligned so as to properly receive the pins formed on the prongs of the connector.
The barrel of the present invention has a generally cylindrical configuration. The restricted end of the barrel has suitable means for attaching a hypodermic needle thereto. The barrel further comprises a protrusion formed inwardly at the open end of the barrel. This protrusion defines an opening having a diameter smaller than the diameter of the shaft. This protrusion serves to restrict the further outward movement of the shaft from the barrel, once the end of the shaft adjacent to the restricted end of the barrel has approached the open end of the shaft.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is cross-sectional view, in side elevation, showing the syringe of the present invention.
FIG. 2 is an exploded view of the present view of the present invention isolating the connector and guide system.
FIG. 3 is a close-up view of the guide system of the present invention.
FIG. 4 is a cross-sectional view of the syringe as assembled prior to use.
FIG. 5 is a detailed view showing the connector of the present invention prior to assembly with the syringe of the present invention.
FIG. 6 is an isolated view, in perspective, of the shaft/guide system configuration of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIG. 1, there is shown the improved non-reusable syringe of the present invention. In particular, FIG. 1 shows the cylindrical barrel 1, shaft 2, piston 3, restricted end 4 of barrel 1, open end 13 of barrel 1, and attachment section 5 for attaching a hypodermic needle or a tube to the syringe of the present invention. The connector system 6 of the present invention is illustrated in block form in FIG. 1.
As can be seen in FIG. 1, barrel 1 has a generally cylindrical configuration. Barrel 1 has an open end 13 through which the shaft 2 passes and a restricted end 4 through which liquid may pass. Hypodermic needles or tubes may be attached to the restricted end 4 of barrel 1.
Shaft 2 acts as the plunger of the syringe of the present invention. Shaft 2 has a generally cruciform cross-section, except for the end containing the guide means, which is a cylindrical solid. The outer diameter of shaft 2 is smaller than the general inner diameter of barrel 1. Shaft 2 is freely slidable within barrel 1. As can be seen in FIG. 1, shaft 2 has a circular end cap 2a at the end of shaft 2 exterior of barrel 1.
Piston 3 is slidably positioned within the interior of barrel 1. Piston 3 forms a liquid-tight seal within the interior of the barrel. Piston 3 has an outer diameter slightly smaller than the inside diameter of barrel 1. This piston 3 is slidable from one end of the barrel 1 to the other end. As will be described hereinafter, piston 3 has a generally open interior area and an orifice through which the one portion of the connector of the present invention may be inserted. In assembly, piston 3 is inserted through the open end of barrel 1. Piston 3 has an end face 3a that is adjacent the restricted end 4 of barrel 1. End face 3a has a surface shape that exactly matches the surface shape of the inside surface of the restricted end 4 of barrel 1.
FIG. 2 shows a more detailed view of the connector system 7 and the guide system 12 of the present invention. In operation, the connector system 7 engages the interior of piston 3. In particular, the connector system 7 has a first end 20 that is inserted into the orifice of piston 3 and is freely rotatable within this interior portion. It is an important aspect of the present invention that the connector 7 be freely rotatable relative to the piston 3. The first end 20 of connector 7 has an arrowhead shape that permits ease of insertion into the orifice of the piston. The "arrowhead" shape allows the end 20 to be inserted but makes removal from the orifice difficult. In practice, the attempted removal of the end 20 from the orifice of piston 3 will result in destruction, deterioration, or damage to the orifice such that reuse of the assembly of the present invention would be difficult. The first linear portion 22 extends outward from this first end 20. Following assembly, first linear portion 22 will extend outwardly beyond the back face 23 of piston 3. A forked member 25 extends outwardly from the end of first linear member 22 opposite first end 20. Forked member 25 includes a first prong 27 and a second prong 29. The first prong 27 extends in one direction outwardly from the first linear member 22. This first prong 27 has an inwardly extending pin 31 formed at the end of the prong 27 opposite the first linear member 22. The second prong 29 also extends outwardly from the end of first linear member 22 in another direction. Second prong 29 also has an inwardly extending pin 33 at its end opposite the linear member 22. Pins 31 and 33 will each engage a groove 12b on opposite sides of guide system 12.
FIG. 5 shows the configuration of connector 7 prior to assembly. Importantly, it can be seen that the prongs 27 and 29 are manufactured so as to be somewhat springy. Following manufacture, as illustrated in FIG. 5, the prongs 27 and 29 tend to come together at the ends 31 and 33. This allows the closing of the prongs following the initial use of the syringe 1 of the present invention and the connector 7 detaches from the guides 12. When the prongs 27 and 29 return to the position shown in FIG. 5, following use of this syringe, it becomes difficult or impossible to cause these pins 31 and 33 to be reinserted into the guide system 12 with the piston 3 and connector 7 remaining in barrel 1. Reassembly becomes additionally difficult because of the free rotation between the connector 7 and the piston.
FIG. 2 also shows the guide system 12 of the present invention. The guide system 12 of the present invention is formed on the exterior of shaft 2. Essentially, a solid cylindrical member 12a is formed at the end of shaft 2 nearest the restricted end 4 of barrel 1. In terms of the manufacturing process, solid cylindrical member 12a and shaft 2 are of unitary configuration. Importantly, however, this should not be considered a limitation of the present invention. It is also possible to manufacture the cylindrical member 12a and the shaft 2 separately and, thereafter, attach them together properly. The diameter of cylindrical member 12 will be less than the inner diameter of the barrel 1 of the syringe of the present invention.
Guide system 12 includes a groove 12b that is formed on the exterior of cylindrical member 12a. In the preferred embodiment of the present invention, there are two grooves formed on the cylindrical member 12a and are located approximately 180 degrees from each other. The first groove 12b is formed on the cylindrical member for receiving one of the pins 31 or 33 of the connector 7 and a second groove is formed (not shown) on the opposite side of the cylindrical member 12a for receiving the other of the pin 31 or 33 of connector 7. These grooves 12b are aligned with one another so as to allow the pins 31 and 33 to slide freely therethrough. Each of the grooves 12b should be of the same shape as the other groove. The minimum width of each of the grooves 12b is slightly greater than the width of the pins 31 or 33.
Each groove is a modified Z-shape. Each groove 12b has an open end 12c at the end of the shaft 2 adjacent the restricted end 4 of barrel 1. The groove has a closed end 12d at the opposite end of the Z-shaped configuration. These grooves 12b are arranged such that the prongs 27 and 29 may be aligned so as to match the opening of the groove.
The shape of the groove 12b is more specifically shown in FIG. 3. The groove 12b begins at the end 12c of shaft 2. As can be seen, groove 12b opens at the end 12c. Groove 12b then forms a first portion 12f that travels straight back extending linearly from open end 12e and is longitudinally aligned with the shaft 2. First portion 12f has a generally constant width and extends to an acute angle corner 12g in the groove 12b. At the acute angle corner 12g, a second portion 12h of groove 12b is formed. This second portion 12h extends at an acute angle from the end 12g of first portion 12f and extends toward the end of shaft 2 adjacent the restricted end of barrel 1. This second portion 12h extends at an acute angle corner 12j. End 12j does not open at the end 12e, but is a closed corner. A third portion 12k extends from corner 12j at the end of the second portion 12h and extends toward the open end of barrel 1. This third portion 12k extends from the second portion 12h at an angle diagonal to the axis of shaft 12. This third portion 12k has a cul-de-sac end 12l opposite corner 12j. In terms of shape, the first portion 12f of groove 12b has generally constant width. The second portion 12h of groove 12b has a constantly increasing width between the end 12g of first portion 12f and the end 12j of third portion 12k. Third portion 12k has generally constant width.
It is through groove 12b that the pins 31 and 33 of prongs 27 and 29 respectively, of connector 7 pass.
As shown in FIG. 3, the various positions of the pins 31 or 33 within groove 12b are shown. Initially, the syringe is delivered to the user such that the pins are in position 1. In position 1, the shaft may be compressed against the pins so as to push the piston 3 against the restrictive end of barrel 4, as in the assembly of the present invention. After the shaft 2 is compressed against the restricted end 4 of barrel 1, the shaft must be pulled outwardly through the barrel 1. This will serve to draw fluid into the hypodermic needle and through the restricted end 4 of barrel 1. In pulling out the shaft to draw the fluid into the barrel 1, the pins will move from position 1 to position 2 through groove 12k and to corner 12j. The pins 31 will abut corner 12j such that the outward movement of shaft 2 will cause piston 3 to be moved through the barrel 1 away from the restricted end 4. After fluid has been drawn into barrel 1, it will be necessary to compress the shaft 2 so as to deliver the fluid to the patient. When the shaft 2 is compressed, pin 31 will move from position 2 to position 3. At position 3, the pin 31 will abut the wall of groove 12h. Pin 31 will then travel along the side of groove 12h until it reaches position 4 at corner 12g. At position 4, the compression of the shaft 2 will cause the piston 3 to move toward the restricted end 4 of barrel 1. It is this action that delivers the medication to the patient.
At this stage of the use of the syringe of the present invention, the pins 31 and 33 remain at position 4 and the piston 3 abuts the restricted end 4 of barrel 1. If a person desires to reuse the syringe following this step, it would be vitally necessary to be able to draw fluids again into barrel 1 by pulling shaft 2 outwardly from barrel 1. Such a movement would cause the pin 31 to move from corner 12g (and position 4) through groove 12f. Ultimately, the pins 31 and 33 would exit the groove 12b by passing to position 5 and position 6. At all times during this second draw, the piston 3 will remain in abutment with the restricted end 4 of barrel 1. Since the pins 31 and 33 would not abut another surface, the piston could not be drawn away from the restricted end 4.
When the pins 31 and 33 are in position 6, the pins 31 and 33, and the associated connector 7, are disconnected from the shaft 2. This disconnects the shaft 2 from the piston 3 such that the shaft 2 may be pulled of towards the open end of the barrel 1 without causing the piston 3 to move toward the open end 13 of barrel 1. Although the shaft 2 may be recompressed into barrel 1, it may only further push the piston 3 toward the restricted end 4 of barrel 1. It would not cause the piston 3 to move toward the open end 13 of barrel 1. The connector 7 cannot be re-engaged with guides 12 because the tips 31 and 33 of prongs 27 and 29 have sprung together. This syringe is thus rendered unable to be filled with a second load of fluid for a second injection and thus is rendered non-reusable after it is filled and emptied once and only once.
The rotatable relationship between the connector 7 and the piston 3 is shown in FIG. 4. It can be seen that the arrowhead-shaped end 20 is inserted into the interior of piston 3. The shape of end 20 prohibits its removal from the end 23 of piston 3. it should be noted that pistons used in current syringes generally have an open interior area. This "free" type of engagement between the end 20 and the interior of piston 3 allows free rotation of the connector 7 with respect to the piston 3. As such, when the connector 7 and the associated pins 31 and 33 are moved to position 6 (shown in FIG. 3), the rotation of the connector 7 will make it difficult or impossible for the pins 31 and 33 to retrace their path in the grooves 12b back to position 1. Additionally, following the use of this syringe, the connector 7 will reform into a shape illustrated in FIG. 5. The internal closing of the prongs following use, will also make it difficult or impossible for the connector 7 to retrace its path through the guide system 12.
FIG. 6 illustrates the configuration of the shaft 2 of the present invention. Following experimentation with a prior-art patent, by the same inventor, it was found that the manufacturing cost of shaft 2 would be significantly less than other non-reusable syringe manufacturing techniques. Importantly, cylindrical member 12a is a solid member. No internal forms or manipulators are required in order to create internal grooves or a cylindrical cavity. In the process of plastic molding, it is a rather simple procedure to mold the Z-shaped groove 12b on a solid cylindrical member 12a. This can be done during the formation of the shaft 2.
The present invention is a non-reusable improvement over present syringes. Importantly, the non-reusable feature of the present invention can be accomplished by the utilization of a single additional component, the connector 7. As such, the non-reusable syringe of the present invention can be manufactured by the molding of the shaft 2 by including the solid cylindrical portion 12a with inscribed groove 12b. In a manufacturing sense, connector 7 is a simple moldable element. The piston 3, as described in the present invention, is a standard piston used on conventional syringes. Because of the simplicity of manufacture, the present invention offers a "non-reusable" alternative to present day syringes.
The present invention provides a safe and automatically self-destroying syringe. Since the syringe of the present invention can only be used one time, it serves to deter the spread of fatal infectious diseases and to deter the theft and abuse of controlled substances. The present invention eliminates the possibility of sharing and reusing a contaminated syringe. The configuration of the present invention offers a cost-effective alternative to present syringes and offers a technique that is easy to manufacture and easy to implement. No additional instruction will be required to enable a physician, or allied health care professional, to properly use the present invention.
The embodiments as illustrated and discussed in this specification are intended only to teach those skilled in the art the best way known by the inventor to make and use the invention. Nothing in the specification should be considered as limiting the scope of the present invention. Many changes could be made by those skilled in the art to produce equivalent systems without departing from the invention. The present invention should only be limited by the following claims and their legal equivalents.
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An improved non-resuable syringe comprising a barrel having one open end and one restricted end through which a liquid may pass, a piston is slidably positioned within the barrel, a shaft is positioned so as to be freely slidable within the barrel and has one end extending beyond the open end of the barrel, a connector has one end engaging the piston in rotatable relation thereto, and a guide means as formed on the exterior of the shaft so as to receive the other end of the connector and causing the connector to disengage from the shaft. The piston has an orifice at one end for receiving an arrowhead-shaped portion of the connector. The connector has a forked portion having inwardly formed pins for engaging guide slots in the exterior of the shaft. The shaft includes a cylindrical member connected to the shaft and a Z-shaped groove configuration formed on opposing sides of the cylindrical member. During use of the syringe, the pins on the connector follow the pathway of the formed groove on the connector.
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TECHNICAL FIELD
The present disclosure relates to a system and method to control ratio changes in an automatic vehicle transmission.
BACKGROUND
Known automatic transmissions for automotive vehicles include step ratio controls for effecting speed ratio changes in response to changing driving conditions. The term “speed ratio”, for purposes of this description, is defined as transmission input shaft speed divided by transmission output shaft speed.
An upshift occurs when the driving conditions require a ratio change from a lower numbered ratio (high speed ratio) to a higher number ratio (low speed ratio) in the transmission gearing. Similarly, a downshift occurs when the driving conditions require a ratio change from a higher numbered ratio (low speed ratio) to a lower number ratio (high speed ratio). The gearing can include, for example, either a planetary type gear system or a lay shaft type gear system. An automatic gear ratio shift is achieved by friction torque establishing devices, such as multiple disk clutches and multiple disk brakes. The friction torque establishing devices include friction elements, such as multiple plate clutches and band brakes, which can be actuated hydraulically.
A step-ratio automatic transmission uses multiple friction elements for automatic gear ratio shifting. A ratio change occurs in a synchronous clutch-to-clutch shift as one friction element, which may be referred to as the oncoming clutch (OCC), is engaged and a second friction element, which may be referred to as the off-going clutch (OGC), is disengaged. Failure to properly coordinate the engagement of the OCC with the disengagement of the OGC can be perceived by the vehicle occupants as an unpleasant shift event. More particularly, early engagement of the OCC relative to the release of the OGC can result in a phenomenon called tie-up. On the other hand, if the OCC is engaged too late relative to the release of the OGC, an engine flare can occur.
SUMMARY
In one embodiment, a method for controlling a transmission is provided. The method ensures proper clutch stroke and minimizes torque transients. During a downshift, a clutch pressure is set for an oncoming clutch at a predetermined stroke pressure. Then the clutch pressure is varied from the predetermined stroke pressure. A resulting torque difference is measured along a torque transmitting element with a torque sensor while the clutch pressure is varied. A clutch control parameter is adjusted if the resulting torque difference is less than a threshold value.
In another embodiment, the torque transmitting element can be, for example, an input shaft or an output shaft.
In yet another embodiment, varying the clutch pressure can involve pulsing the clutch pressure above the predetermined stroke pressure, pulsing the clutch pressure below the predetermined pressure, gradually increasing the clutch pressure in a ramp profile, or other means.
In some embodiments, the method can include setting the clutch pressure at a boost pressure higher than the predetermined stroke pressure for a boost duration before setting the clutch pressure at the predetermined stroke pressure.
In still another embodiment, the clutch control parameter to be adjusted can be, for example, the predetermined stroke pressure, the boost pressure, or the boost duration.
In one other embodiment, a method for controlling a transmission is provided. The method includes varying a clutch pressure around a predetermined value in advance of a torque phase of a shift event. A torque change is measured in a transmission element as the clutch pressure is varied. A clutch control parameter is adjusted in response to the measured torque change.
In another embodiment, the value can be increased if the change in measured torque is below a first threshold.
In another embodiment, the value can be decreased if the change in measured torque is above a second threshold.
In another embodiment, the shift event can be a downshift and the clutch can be the oncoming clutch for the downshift.
In on other embodiment, a transmission is provided. The transmission includes a clutch having a torque capacity based on a fluid pressure and a torque sensor adapted to measure a torque value that varies in relationship to the torque capacity. A transmission controller is configured to vary the fluid pressure from a predetermined value in advance of a torque phase of a shift event and adjust the predetermined value in response to a change in the measured torque value.
The above advantages and other advantages and features will be readily apparent from the following detailed description of the preferred embodiments when taken in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic diagram illustrating a transmission;
FIG. 2 is a schematic diagram of a transmission clutch or brake;
FIG. 3 is a graph illustrating a downshift under idealized clutch pressure control;
FIG. 4 is a graph illustrating a downshift under open loop clutch pressure control in which the oncoming clutch pressure is set too high;
FIG. 5 is a graph illustrating a downshift under open loop clutch pressure control in which the oncoming clutch pressure is set too low;
FIG. 6 is a flow chart illustrating a first embodiments of a closed loop pressure control algorithm;
FIG. 7 is a graph illustrating a downshift under the closed loop clutch pressure control system of FIG. 6 in which the initial oncoming clutch pressure is set too high;
FIG. 8 is a graph illustrating a downshift under the closed loop clutch pressure control system of FIG. 6 in which the initial oncoming clutch pressure is set too low;
FIG. 9 is a flow chart illustrating a second embodiments of a closed loop pressure control algorithm; and
FIG. 10 is a graph illustrating a downshift under the closed loop clutch pressure control system of FIG. 9 .
DETAILED DESCRIPTION
As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely examples of the invention that can be embodied in various and alternative forms. The figures are not necessarily to scale; some features may be exaggerated or minimized to show details of particular components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art to variously employ the present invention.
FIG. 1 illustrates a six speed planetary transmission 18 with three planetary gear sets 20 , 22 , and 24 . Each planetary gear set includes a sun gear, a ring gear, a planet carrier, and a collection of planet gears supported for rotation about the planet carrier and meshing with both the sun gear and the ring gear. The carrier of gear set 20 is fixedly connected to the ring gear of gear set 22 , the carrier of gear set 22 is fixedly connected to the ring gear of gear set 24 , and the carrier of gear set 24 is fixedly connected to the ring gear of gear set 20 . Input shaft 26 is fixedly connected to the sun gear of gear set 22 and output shaft 28 is fixedly connected to the carrier of gear set 24 .
Various power flow paths between input shaft 26 and output shaft 28 are established by the selective engagement of clutches and brakes. Brakes 30 , 32 , and 34 selectively hold the sun gear of gear set 20 , the carrier of gear set 20 , and the sun gear of gear set 24 , respectively, against rotation. Clutches 36 and 38 selectively connect the sun gear of gear set 20 and the carrier of gear set 20 , respectively, to input shaft 26 . Table 1 indicates which clutches and brakes are engaged in order to establish each of the six forward and one reverse transmission ratios. Torque sensor 40 senses the torque transmitted to the output shaft and electrically communicates that information to controller 42 . The controller 42 can, for example, be part of a vehicle system control module or transmission control module or can be a stand-alone controller.
TABLE 1
Brake 30
Brake 32
Brake 34
Clutch 36
Clutch 38
Reverse
X
X
1st
X
X
2nd
X
X
3rd
X
X
4th
X
X
5th
X
X
6th
X
X
While an automatic transmission according to an embodiment of the disclosure can be a planetary type as shown in FIG. 1 , it is also contemplated that the transmission can be a lay shaft type transmission. Similarly, a speed ratio change can be achieved by the friction elements as described above, or the friction elements can be plate clutches or band brakes.
FIG. 2 illustrates a representative cross section of a clutch, such as clutches 36 and 38 and brakes 30 , 32 , and 34 in FIG. 1 . A set of friction plates 44 is splined to a clutch hub 46 . The friction plates 44 are interspersed with a set of separator plates 48 that is splined to a clutch cylinder 50 . In the disengaged state as shown here in FIG. 2 , there is space between the friction plates 44 and the separator plates 48 such that the hub 46 and the cylinder 50 are free to rotate at different speeds with respect to each other.
To engage the clutch, pressurized fluid is forced into the cylinder 50 . The pressure is supplied by a pump 52 . The controller 42 regulates the hydraulic pressure indirectly by setting an electrical current in a solenoid 54 which controls the position of a valve 56 . The pressurized fluid travels through a hydraulic passageway 58 to the clutch cylinder 50 . The pressurized fluid forces the piston 60 to slide within the cylinder 50 and squeeze the friction plates 44 and separator plates 48 together. Friction between the friction plates 44 and the separator plates 48 resists relative rotation of hub 46 and cylinder 50 . When the fluid pressure is removed, a return spring 62 forces the piston 60 to slide in the opposite direction returning the clutch to the disengaged state.
The torque capacity of the clutch depends upon the fluid pressure but the relationship is complicated by several factors. First, there is a time delay between when fluid starts flowing to the cylinder 50 and when the piston 60 has moved far enough to start squeezing the friction plates 44 and separator plates 48 together. The torque capacity of the clutch is nearly zero during this period before the piston 60 is fully stroked. When the piston 60 has moved such that it can apply force to the plates 44 , 48 , the piston and clutch are said to be stroked. Secondly, some amount of pressure, called the stroke pressure, is required to overcome the force of the return spring 62 even after the piston 60 is stroked.
Once the piston 60 is stroked, the clutch torque capacity is proportional to the fluid pressure minus the stroke pressure. However, a variety of unpredictable noise factors influence the relationship between the solenoid 54 current as commanded by the controller 42 and the torque capacity so that the commanded torque capacity may not be accurately achieved. For example, variations in the coefficient of friction, frictional forces between the piston 60 and the cylinder 50 , and pressure variations in the passageway 58 , may cause the actual torque capacity to be either higher or lower than commanded.
These noise factors can make it difficult to achieve a smooth shift behavior without torque transient conditions that may be perceptible to a driver. A downshift from one speed ratio to another requires the coordinated application of one clutch and release of another. For example, to shift from sixth gear to fifth gear, brake 30 (the OGC) is released while clutch 38 (the OCC) is applied, as described in Table 1. As discussed above, noise factors make it more difficult to achieve a smooth shift behavior using only open loop control strategies. The disturbances associated with pressure control inaccuracy are best understood in relation to the intended behavior which is illustrated in FIG. 3 . As discussed below, actual control strategies do not repeatably achieve this behavior.
FIG. 3 illustrates how a downshift process would ideally be executed if there were no noise factors and the controller could command precisely the right amount of torque capacity. The holding pressure for the OGC would be set to the pressure at which the torque capacity of the OGC equals the torque carried by the OGC in the initial gear. To initiate the shift, the controller would reduces the pressure to the OGC to a level slightly below the holding pressure as shown at 102 , marking the beginning of the inertia phase.
During the inertia phase, the input speed would increase to the correct multiple of the output speed for the destination ratio, as shown at 104 . The output torque would drop slightly, as shown at 106 , because some of the input power would be consumed to overcome the inertia of elements connected to the input. During the inertia phase, the OCC would be stroked in preparation for the torque transfer phase. The commanded pressure to the OCC would be elevated to a high pressure, P boost , for a short interval, t boost , to rapidly fill the cylinder with fluid and move the piston to the stroke position, as shown at 108 . Then, the commanded pressure would be maintained at a pressure near the stroke pressure. In FIG. 3 , the actual pressure is shown equal to the stroke pressure at 110 , which would keep the piston stroked but not apply any torque.
Once the input speed reaches the correct multiple of the output speed at 112 , the torque transfer phase begins. During the torque transfer phase, the commanded pressure to the OGC would be gradually reduced 114 while the commanded pressure to the OCC is gradually increased 116 . Ideally, the torque capacity of the two clutches would be coordinated such that the input speed remains constant 118 and the output torque gradually increases 120 . The torque transfer phase is complete when the OCC pressure is above its holding pressure 122 and the OGC pressure is below its stroke pressure 124 . The commanded pressure of the OCC would then be further increased to provide some margin over the holding pressure as shown at 126 .
While FIG. 3 illustrates an ideal system without noise factors, the actual pressure will generally only approximate the stroke pressure. In the absence of a feedback signal, it is difficult to determine if the commanded pressure has being achieved.
FIGS. 4-5 illustrate the potential problems associated with the noise factors and subsequent pressure control errors in an open loop control strategy. FIG. 4 illustrates an effect of accidentally commanding an OCC pressure above the stroke pressure during the inertia phase 128 . Once the OCC is stroked, the torque capacity increases to a positive value 130 . Since the speed ratio at this point is below the speed ratio of the destination gear, torque capacity of the OCC produces a drop in the output torque 132 . The vehicle occupants perceive this fluctuation in output torque as a rough and jerky shift event.
FIG. 5 illustrates an effect of accidentally commanding an OCC pressure below the stroke pressure 134 . In this circumstance, the OCC is not fully stroked by the beginning of the torque transfer phase. As the commanded pressure of the OCC is increased in the torque transfer phase, there is a delay before the OCC torque capacity begins to increase 136 . During this delay period, the input speed continues to increase above the speed ratio of the destination gear as shown at 138 . This is called an engine flare. Eventually, the OCC torque capacity increases enough to bring the input speed back to the desired level 140 . The output torque changes suddenly 142 when the input speed returns to the destination gear speed ratio which occupants perceive as a rough and jerky shift event.
FIG. 6 illustrates a flow chart of a control system for a transmission using closed loop control during a ratio shift. As those of ordinary skill in the art will understand, the functions represented by the flowchart blocks can be performed by software and/or hardware. Also, the functions can be performed in an order or sequence other than that illustrated in FIG. 6 . Similarly, one or more of the steps or functions can be repeatedly performed although not explicitly illustrated. Likewise, one or more of the representative steps of functions illustrated can be omitted in some applications. In one embodiment, the functions illustrated are primarily implemented by software instructions, code, or control logic stored in a computer-readable storage medium and if executed by a microprocessor based computer or controller such as the controller 50 .
FIG. 6 is a flow chart for one embodiment of the present disclosure for using a torque sensor for detecting improper stroke and using closed loop control during a ratio shift. Initially when a ratio shift is requested, the controller raises the OCC pressure to a boost pressure P boost for a boost time t boost in order to quickly move the piston to a substantially stroked position, as represented by blocks 60 and 62 . The boost pressure P boost is a clutch control parameter significantly above the stroke pressure P stroke . For example, the boost pressure can be the maximum available pressure based on limits of the solenoid. The boost time t boost is a clutch control parameter calculated to be long enough to substantially stroke the clutch and short enough that the clutch does not prematurely transmit torque.
Then, the controller commands the OCC to an estimated stroke pressure P stroke — est and waits for a period t test calculated to be long enough for the piston to reach an equilibrium position as represented by blocks 64 and 66 . Both P stroke — est and t test are clutch control parameters. Initial values for all clutch control parameters can be established experimentally based on vehicle testing and can be adjusted adaptively during vehicle operation. In this illustrative example, P stroke — est is adjusted adaptively.
At 68 , the controller records a reference reading τ ref from a torque sensor 40 . The torque sensor can measure the torque on the output shaft as shown in FIG. 1 , the input shaft, or any other element that transmits torque in the destination gear. At 70 , the controller commands a pressure variation P test above or below the estimated stroke pressure P stroke — est . The incremental pressure P test is calculated to be enough of a pressure variation to generate a change in the torque measured by the torque sensor 40 if the clutch is fully stroked. However, the pressure variation can be small enough that the change in torque would not be objectionable or even noticeable to the vehicle occupants.
At 72 , the controller records a second reading τ test from the torque sensor 40 . At 74 , the controller compares the two torque readings, τ ref and τ test , to determine if the difference between τ ref and τ test differ by more than a threshold amount τ threshold . The threshold amount τ threshold is calculated to be large enough that short term variations due to noise factors are not erroneously attributed to the change in commanded pressure. If the two pressures, τ ref and τ test , differ by less than the threshold amount τ threshold , this is indicative that the piston was not fully stroked. If the piston is not fully stroked, then the estimated stroke pressure is increased as represented by block 76 . On the other hand, if the two pressures, τ ref and τ test , differ by more than the threshold amount τ threshold , this is indicative that the piston was fully stroked. If the piston is fully stroked, then the estimated stroke pressure is decreased, as represented by block 78 . At 80 , the controller commands the revised estimated stroke pressure.
Finally, if there is time remaining before the end of the inertia phase, another adjustment is performed. Otherwise, the process ends and the revised estimated stroke pressure is utilized in future shift events involving that OCC.
FIG. 7 illustrates the results of utilizing the control strategy of FIG. 6 when the initial estimated stroke pressure is higher than a required stroke pressure as shown at 144 . When the estimated stroke pressure is too high, the clutch is fully stroked and has positive torque capacity 146 . When the clutch is fully stroked, the upward 148 and downward 150 perturbations in commanded pressure produce measurable changes in torque as shown at 152 and 154 which are detectable by the torque sensor. For example, the upward perturbation 148 results in the measured torque reading τ test1 156 . The torque perturbation is compared to a reference torque value τ ref1 158 . If the difference between the measured torque readings, τ test1 and τ ref1 , is greater than a threshold amount τ threshold , then the estimated stroke pressure is decreased. The controller commands this decreased stroke pressure 160 .
Prior to a second perturbation 150 , a revised reference torque value τ ref2 162 is measured. Following the perturbation, a second torque reading τ test2 164 is measured. Even though the new commanded pressure is below the required stroke pressure, the torque difference still exceeds the threshold, resulting in another downward adjustment. The commanded pressure is set to the new adjusted value as show at 166 . Please note, the perturbations in pressure and torque may be exaggerated for illustrative purposes.
FIG. 8 illustrates the results when the initial estimate of stroke pressure is below the actual stroke pressure as shown at 168 . When the estimated stroke pressure is too low, the clutch is not fully stroked and has zero torque capacity 170 . In this unstroked condition, perturbations in commanded pressure do not produce a measurable change. For example, as illustrated, upward pressure pulse 172 and downward pressure pulse 174 do not affect output torque 176 . Consequently, then the estimated stroke pressure can be increased after each perturbation. The controller commands this increased stroke pressure as shown at 178 and 180 .
FIG. 9 is a flow chart for another embodiment of the present disclosure where the initial estimate of the stroke pressure is intentionally set slightly below the required stroke pressure and gradually increased until a measurable change is detected. Blocks 60 through 68 are identical to the previously described embodiment except that the initial estimate is decreased from the previous value at block 86 . Blocks 88 , 90 , 92 , and 94 form a loop in which the estimated stroke pressure and the commanded pressure is gradually increased until the torque sensor indicates a change in measured torque. The increment added to P stroke — est in each iteration can be small compared to the increment used at blocks 76 and 78 of FIG. 6 or block 86 of FIG. 9 .
FIG. 10 illustrates the results of utilizing the control strategy described in FIG. 9 . After the boost phase, the clutch pressure is set to a value below the stroke pressure at 182 . Because the clutch is not fully stroked, the clutch torque capacity is zero 184 . The reference torque value τ ref 186 is measured. Then, the commanded pressure is gradually increased, as shown at 188 . Once the commanded pressure reaches the stroke pressure, the clutch torque capacity will begin to increase above zero, as shown at 190 , and the output torque will begin to decrease, as shown at 192 . In each iteration, a new test torque τ test 194 is measured until the difference between the measured torque readings, τ test and τ ref , is greater than a threshold amount τ threshold 196 .
While exemplary embodiments are described above, it is not intended that these embodiments describe all possible forms of the invention. Rather, the words used in the specification are words of description rather than limitation, and it is understood that various changes may be made without departing from the spirit and scope of the invention. Additionally, the features of various implementing embodiments may be combined to form further embodiments of the invention.
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A transmission and control method are disclosed which ensure proper stroke pressure and minimize torque transients during a shift event. The transmission includes a clutch having a torque capacity based on a fluid pressure, a torque sensor adapted to measure a torque value that varies in relationship to the torque capacity, and a controller. The method includes varying the fluid pressure around a predetermined value, measuring a resulting torque difference with the torque sensor, and adjusting a clutch control parameter if the resulting torque difference is less than a threshold value.
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FIELD OF THE INVENTION
[0001] The technical field of the present invention pertains to a device, which is integrated into the framework of floating slabs, as an instrument for raising the slab once the concrete has set. These floating slabs are arranged in constructions that require an insulation of the central block, as they may be the bases at which are situated electric transformers, air conditioning units, bowling alleys and, generally, sites at which it is desired to avoid the transmission of vibrations and impact noises.
BACKGROUND OF THE INVENTION
[0002] The system of creating floating slabs by means of distributing metallic containers in welded wire fabric in the form of cubes that are within the forging is known. The raising phase occurs once the concrete has set, and shock-absorbing elements are positioned in the cavity, which are coupled under beveled structures that are located in two of the corners thereof. In this way, the raising of the floating slab will be achieved to the extent desired by means of the pressure of the shock absorbers in its upper part.
[0003] The welded wire fabric is usually formed by two meshes or rebar surfaces, each of which are created by bars that intersect one another at right angles, forming grids, whose points of contact are joined by welding. These are positioned superimposed, trying to align the grids of the two meshes for the correct insertion of cubes which have a height similar to that of the welded wire fabric, and are positioned within the two caps of same so that, after the setting of the concrete, they are close in the forging. For this purpose, a plurality of metallic rods are installed welded on the surface of each cube in the horizontal direction which protrude from their structure. In fixing to the rebar, in order to avoid the displacement thereof in the pouring phase of the concrete, once in the grid, the rods are fastened to the welded wire fabric by means of wires. This involves a lot of work for the operator in the positioning and a limited rigidity of the system, causing the cubes to move when the concrete is poured or by the operator's own movements within the rebar. If the setting occurs with any of these elements displaced or twisted, there will be a weak zone at this point which may cause the fracture of the floating slab in the raising phase.
[0004] The grid of the welded wire fabric is produced by having different proportions. The prior-art system has the drawback that the rods welded to the structure of the cube are arranged so that they cover the grid in every case, to facilitate its bundling by means of wire. For this the operator usually has problems at the time of fitting the cube in the welded wire fabric, and has to shorten the rebar to make a suitable cavity. Apart from the labor-intensive work that it involves, it results in a structure that is hazardous to the work zone, which the ends of the rods welded together with the cuts made in the rebar constitute, with many sharp points, with risk to the operator in the work of positioning the wires or by the fact alone of being situated on the structure.
[0005] The welded wire fabric is manufactured in different extension dimensions for the different positioning sites. For this, the bonding of one surface of the welded wire fabric with those [surfaces] which follow it in the work is necessary. It is equally necessary to fix the corners of the layers of the welded wire fabric, if a worker or operator goes through zones remote from the center, this force then causes the structure to rise.
[0006] Another type of element is known for arranging in the forging that is made up of a metallic cylinder with walls of considerable size, within which the shock absorber is arranged, having two horizontal projections in its contour for being situated in the rebar. The complexity of this structure makes the manufacture thereof very expensive, and the securing in the welded wire fabric, in spite of the weight that it has, is insufficient.
DESCRIPTION OF THE INVENTION
[0007] The present invention that is proposed fully solves the problems mentioned by presenting a device in the form of a cube which has various horizontal tubes in its perimetral structure, at various levels, suitable for rods being inserted therein, which project from the sides of the cube for placing the different layers of welded wire fabric above them. In this way, the first layer of the welded wire fabric will rest on the rods arranged in the lower tubes of the cube, which are facing on two of its sides; a second welded wire fabric arranged above the rods of the upper tubes, placed on the other two opposite sides of the cube.
[0008] The bonding of the different mesh structures of the work is carried out by means of the rods installed in the lower tubes which support the first welded wire fabric, which connect the cubes of the adjoining mesh surfaces.
[0009] Rods will be placed in the upper tubes parallel to the above tubes for the bonding of two adjacent cubes which are close to the corners of two welded wire fabric surfaces. This upper linking together will prevent the raising of the mesh when a pressure goes or is applied outside of the central zone.
[0010] The object of the present invention is accomplished with a lid and a base for the interior insulation in the pouring of the concrete.
DESCRIPTION OF THE DRAWINGS
[0011] To complement the description that is being provided and to aid in a better understanding of the features of the present invention, the present specification is accompanied by drawings showing the preferred embodiment, in which, in an illustrative and nonlimiting nature:
[0012] FIG. 1 shows the left elevation (A), front elevation (B) and plan view (C) of the cube that is the subject of the present invention.
[0013] FIG. 2 shows a view of the cubes in a first phase of positioning.
[0014] FIG. 3 shows us a view of the positioning of the first mesh in the work with two surfaces of same aligned.
PREFERRED EMBODIMENT OF THE INVENTION
[0015] Viewing the figures shown, it can be seen how the device for positioning floating slabs is composed of a metallic cube, whose base will have a smaller dimension than the surface of the grid of the mesh and have a height in relation to that of the forging; and in its perimeter it has identical tubes which are preferably attached to the structure by means of welding.
[0016] Each side has two pairs of tubes placed in parallel, horizontally, and same have proportions that do not exceed the length of the side ( FIG. 1 ), (C), and they are placed on each side at a same position with respect to its side of the opposing cube (A, B); and the tubes of two of the opposing sides (A) are situated at a different level with respect to the other two sides (B), and the latter are situated closer to the base ( 1 , 1 ′) and closer to the height ( 3 , 3 ′) of the cube than the tubes of its adjoining sides ( 4 , 4 ′) and ( 2 , 2 ′).
[0017] The first mesh of the structure of the welded wire fabric will be situated above the rods of the lower tubes, according to FIG. 2 .
[0018] In the adjoining meshes, the rods of the lower tubes will be inserted therein in both pieces, connecting both surfaces of the structure ( 5 ).
[0019] The mesh is formed by means of arranging bars vertically with other horizontal bars, some on top of others, securing the bonding at the points of contact by welding. The rods of the lower tubes will be situated on the same plane and parallel to the lower bars of the mesh, holding the bars perpendicular to the above ones.
[0020] The second mesh has to be positioned in the same way, with the rods installed in the upper tubes which are on the other two sides of the cube ( 2 , 2 ′). Also, in this way, with the rods on the same plane and in parallel to the lower bars of the mesh.
[0021] The separation between the lower tubes and upper tubes for positioning the mesh will be sufficient for the entry of the concrete, on the understanding that there may be little separation that the cavities will have in the pouring which will put the consistency of the future floating slab at risk.
[0022] In the cubes belonging to two mesh surfaces that are located close to the corners, rods will be placed and inserted in the upper tubes which are on the same side as the lower tubes, whose rods support the first mesh, and inserted in the two adjacent pieces ( 3 , 3 ′). It will also be used for anchoring the structure and the mesh is not raised when exerting pressure in an opposite zone. In FIG. 3 is only shown the first welded wire fabric, and it has to be understood that the second one will be situated superimposed and in the manner that is described.
[0023] The figure shows two joined meshes (I, II) beginning at the joined corners, and it has to be understood that the surfaces of the same are not shown complete in the horizontal direction.
[0024] The other two tubes that are in the structure of the cube, arranged parallel to the upper tubes for the installation of the rods that support the second mesh and in a plane lower than those ( 4 , 4 ′) will be used for the installation of other additional rods when the slab has to support major loads.
[0025] The cube has a lid and a base coated with rustproof paint, and both are assembled by compression to avoid the entrance of the pourable concrete mix. As a complement, the lid is arranged sealed with silicone. The lid and base are painted different colors for quickly checking before pouring the concrete whether any of the cubes are in the incorrect position.
[0026] When the concrete has set, the lids of the cubes will be removed, and shock absorbers will then be placed which will make the raising of the slab possible. In this most suitable embodiment, another shock absorber, in this case, a high-frequency, Silent block type absorber, will be placed on the bottom, which will facilitate the movement of the shock absorber arranged above same.
[0027] It should be understood that the present invention was described according to the preferred embodiment of same; therefore, it may be susceptible to modifications in shape, size and materials, provided that said changes do not substantially vary the features of the present invention as they are claimed below.
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A device to be placed in floating floor slabs and the installation system thereof, the device comprising a cube having a pair of tubes on each side thereof, parallel with the base, with facing sides in identical position; within said sides a section designed for placing rods on which the different layers of the rebar mesh are supported and a system for fitting the mesh on the rods, and also the securing of the corners of the different levels of the rebar mesh by means of linking of the cubes using the rods.
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CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims benefit to U.S. Patent Application No. 62/069,379, filed on 2014 Oct. 28, which is hereby incorporated by reference.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT (IF APPLICABLE)
[0002] Not applicable.
REFERENCE TO SEQUENCE LISTING, A TABLE, OR A COMPUTER PROGRAM LISTING COMPACT DISC APPENDIX (IF APPLICABLE)
[0003] Not applicable.
BACKGROUND OF THE INVENTION
[0004] This disclosure relates generally to a Sport Equipment Container. Examples of similar disclosures can be found at U.S. Pat. No. 4,671,406, U.S. Pat. No. 6,213,574, U.S. Pat. No. 7,293,748, US2008/00268879, US2011/0262259, US2012/0298537, and D478808. However, none of the known inventions and patents, taken either singularly or in combination, is seen to describe the instant disclosure as claimed. Accordingly, said Sport Equipment Container would be advantageous.
BRIEF SUMMARY OF THE INVENTION
[0005] A bucket storage system is disclosed. Said bucket storage system comprising a pail and a sleeve. Said pail comprising a base and a sidewall. Said pail contains a bucket cavity configured to store and hold sports equipment. Said pail comprises a bottom diameter and a top diameter. Said bucket cavity comprises a space above said base comprises and within said sidewall of said pail. Said sleeve comprises a sidewall and a sleeve cavity. Said sleeve comprises a upper sleeve diameter and a lower sleeve diameter. Said upper sleeve diameter is greater in size than said lower sleeve diameter. Said upper sleeve diameter is smaller than said top diameter of said pail;
[0006] a portion of said sleeve is configured to selectively slide into and out of said pail for storage and use. Said bucket storage system comprises a collapsed configuration and a one or more assembled configurations. Said collapsed configuration comprises said sleeve nested within said pail; and. Said one or more assembled configurations comprise said pail upside down with said sleeve stacked on top of said pail.
[0007] A bucket storage method, comprising: removing said lid from said pail, replacing said lid if necessary for transport or storage, removing said lid if reattached to said pail, removing said one or more ball from said bucket cavity, attaching said lid to said pail, inverting said pail, fitting said sleeve on said pail, and placing said one or more ball in said sleeve cavity; wherein. Said bucket storage system comprising a pail and a sleeve. Said pail comprising a base and a sidewall. Said pail contains a bucket cavity configured to store and hold sports equipment. Said pail comprises a bottom diameter and a top diameter. Said bucket cavity comprises a space above said base comprises and within said sidewall of said pail. Said sleeve comprises a sidewall and a sleeve cavity. Said sleeve comprises a upper sleeve diameter and a lower sleeve diameter. Said upper sleeve diameter is greater in size than said lower sleeve diameter. Said upper sleeve diameter is smaller than said top diameter of said pail. A portion of said sleeve is configured to selectively slide into and out of said pail for storage and use. Said bucket storage system comprises a collapsed configuration and a one or more assembled configurations. Said collapsed configuration comprises said sleeve nested within said pail; and. Said one or more assembled configurations comprise said pail upside down with said sleeve stacked on top of said pail.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
[0008] FIG. 1 illustrates a perspective overview of a bucket storage system 100 in a collapsed configuration 120 with a ball 108 and a sporting equipment 110 .
[0009] FIGS. 2A, 2B, and 2C illustrate a perspective overview of said pail 102 with said lid 104 , an elevated top view of said lid 104 , and a side view of said pail 102 with said lid 104 .
[0010] FIGS. 3A, 3B, and 3C illustrate a cross-section side view of said pail 102 with said lid 104 in a closed position, a cross-section side view of said pail 102 with said lid 104 in an expanded position, and an elevated side view of said pail 102 and said lid 104 in an expanded position.
[0011] FIGS. 4A and 4B illustrate a perspective overview and an elevated overview of said sleeve 106 and a top-down view of said sleeve 106 .
[0012] FIGS. 5A, 5B, 5C and 5D illustrate a perspective overview of said bucket storage system 100 in said collapsed configuration 120 , an exploded view 502 , a first assembled configuration 504 , and a second assembled configuration 506 .
[0013] FIGS. 6A and 6B illustrate a cross-section side view of a storable sleeve 602 stored inside said pail 102 and a cross-section side view of said storable sleeve 602 mounted internally within a lip 604 of said pail 102 . FIG. 6C illustrates said bucket storage system 100 with a threading lock between said pail 102 and said storable sleeve 602 .
[0014] FIGS. 7A and 7B illustrate a cross-section side view of a storable sleeve 702 stored inside said pail 102 and a cross-section side view of said storable sleeve 702 mounted externally of said lip 604 of said pail 102 .
[0015] FIGS. 8A and 8B illustrate a side view of said bucket storage system 100 and a cross-section side view of said bucket storage system 100 containing a one or more said ball 108 .
[0016] FIGS. 9A and 9B illustrate a side view of said bucket storage system 100 in a lowest height configuration 902 and a side view of said bucket storage system 100 in a maximum height configuration 904 .
[0017] FIGS. 10A, 10B and 10C illustrate a bucket storage system 1000 in a collapsed configuration 1010 , an exploded configuration 1012 , and an assembled configuration 1014 .
DETAILED DESCRIPTION OF THE INVENTION
[0018] Described herein is a sport equipment container. The following description is presented to enable any person skilled in the art to make and use the invention as claimed and is provided in the context of the particular examples discussed below, variations of which will be readily apparent to those skilled in the art. In the interest of clarity, not all features of an actual implementation are described in this specification. It will be appreciated that in the development of any such actual implementation (as in any development project), design decisions must be made to achieve the designers' specific goals (e.g., compliance with system- and business-related constraints), and that these goals will vary from one implementation to another. It will also be appreciated that such development effort might be complex and time-consuming, but would nevertheless be a routine undertaking for those of ordinary skill in the field of the appropriate art having the benefit of this disclosure. Accordingly, the claims appended hereto are not intended to be limited by the disclosed embodiments, but are to be accorded their widest scope consistent with the principles and features disclosed herein.
[0019] FIG. 1 illustrates a perspective overview of a bucket storage system 100 in a collapsed configuration 120 with a ball 108 and a sporting equipment 110 .
[0020] In one embodiment, said bucket storage system 100 can comprise components including but not limited to a pail 102 , a lid 104 , and a sleeve 106 . In one embodiment, said bucket storage system 100 can provide ease of access to users in storing sporting goods such as said ball 108 and said sporting equipment 110 . For instance, said bucket storage system 100 can provide both storage within said pail 102 but can also provide elevated storage within said sleeve 106 (not illustrated here, see below). Elevated storage within said sleeve 106 would enable a user of said bucket storage system 100 to access items in an upright standing position without crouching or bending over. In one embodiment, said lid 104 and said sleeve 106 can be adjusted in relation to said pail 102 to reduce the size of and provide easier transportation of said bucket storage system 100 .
[0021] FIGS. 2A, 2B, and 2C illustrate a perspective overview of said pail 102 with said lid 104 , an elevated top view of said lid 104 , and a side view of said pail 102 with said lid 104 .
[0022] In one embodiment, said pail 102 can comprise a sidewall 202 and a handle 208 with a grip 214 . Said lid 104 can comprise a sidewall 204 . In one embodiment, said sidewall 202 and said sidewall 204 can be a substantially cylindrical shape, as illustrated. In one embodiment, said bucket storage system 100 can be made of plastics, metal, or wood.
[0023] In one embodiment, said handle 208 can attach to said bucket storage system 100 at opposing sides of said sidewall 202 with a handle anchor 210 and a handle anchor 212 .
[0024] In one embodiment, said lid 104 can comprise a top surface 206 and said sidewall 204 . In one embodiment, said top surface 206 can comprise a similar material to said sidewall 204 or a textured or different material to provide a non-slip surface when said top surface 206 is placed against another surface. In one embodiment, said handle 208 attaches to said sidewall 204 on said lid 104 (not illustrated here as attached to said lid).
[0025] In one embodiment, said pail 102 can have varying diameters while said lid 104 can have a single diameter. Meaning said lid 104 can comprise a true cylindrical shape and said pail 102 can be more conical. For instance, said pail 102 can have a top diameter 218 and a bottom diameter 220 where said top diameter 218 is larger than said bottom diameter 220 . On the other hand, said lid 104 can have a lid diameter 216 wherein said lid diameter 216 is larger than said top diameter 218 .
[0026] FIGS. 3A, 3B, and 3C illustrate a cross-section side view of said pail 102 with said lid 104 in a closed position, a cross-section side view of said pail 102 with said lid 104 in an expanded position, and an elevated side view of said pail 102 and said lid 104 in an expanded position.
[0027] In one embodiment, said lid 104 can be removeably attached to said pail 102 . Furthermore, a bucket cavity 302 in the area within said pail 102 and said lid 104 can be expanded or compacted depending on the location of said lid 104 in relation to said pail 102 . For instance, said pail 102 and said lid 104 can have a compacted height 304 when said lid 104 is fully attached to said pail 102 . In one embodiment, said lid 104 has lid threading 308 that is complementary to said pail threading 306 on said pail 102 . Specifically, said lid 104 can be rotateably adjusted in relation to said pail 102 to adjust the vertical position of said lid 104 . In one embodiment, said pail 102 can have a pail height 310 while said lid 104 can have a lid height 312 thus having an expanded height 314 . In one embodiment, said lid 104 can be adjusted on said pail 102 to have a height between said compacted height 304 and said expanded height 314 .
[0028] FIGS. 4A and 4B illustrate a perspective overview and an elevated overview of said sleeve 106 and a top-down view of said sleeve 106 .
[0029] In one embodiment, said sleeve 106 can have a sidewall 402 . In one embodiment, said sidewall 402 can be cylindrical and comprise of plastics, metal, or wood. In one embodiment, said sleeve 106 can have a sleeve height 406 . Additionally, said sleeve 106 can have an upper sleeve diameter 408 and a lower sleeve diameter 410 . As a result, said sleeve 106 can taper from top to bottom. In one embodiment, said sleeve 106 can have a sleeve cavity 404 in the aperture space between said sidewall 402 .
[0030] In one embodiment, said sleeve 106 can comprise a one or more handles 412 (which can comprise a first handle 412 a and a second handle 412 b ), as illustrated. Said one or more handles 412 can be used to remove said sleeve 106 from said pail 102 when nested within said pail 102 .
[0031] FIGS. 5A, 5B, 5C and 5D illustrate a perspective overview of said bucket storage system 100 in said collapsed configuration 120 , an exploded view 502 , a first assembled configuration 504 , and a second assembled configuration 506 .
[0032] In one embodiment, said sleeve 106 can be placed and removed with no tools. In one embodiment, said sleeve 106 can stay attached to said pail 102 via friction between said sleeve 106 and said pail 102 . When said sleeve 106 is attached to said pail 102 , a base 320 separates said bucket cavity 302 and said sleeve cavity 404 . Essentially, said base 320 provides a separation of storage in said bucket storage system 100 and elevated storage in said sleeve cavity 404 .
[0033] In one embodiment, said bucket storage system 100 can comprise a one or more assembled configuration which can comprise said first assembled configuration 504 and said second assembled configuration 506 .
[0034] FIGS. 6A and 6B illustrate a cross-section side view of a storable sleeve 602 stored inside said pail 102 and a cross-section side view of said storable sleeve 602 mounted internally within a lip 604 of said pail 102 . FIG. 6C illustrates said bucket storage system 100 with a threading lock between said pail 102 and said storable sleeve 602 .
[0035] In one embodiment, said storable sleeve 602 can be stored within said pail 102 during transport or when bucket storage system 100 is not in use. In one embodiment, said bucket storage system 100 can be setup by removing said storable sleeve 602 from said pail 102 , inverting said pail 102 , and fitting said storable sleeve 602 within said lip 604 . In one embodiment, said base 320 serves as a separation between said bucket cavity 302 and said sleeve cavity 404 . As a result, said sleeve cavity 404 can be elevated and provide ease of access to items placed within said sleeve cavity 404 .
[0036] In one embodiment, said pail 102 can lock into said lip 604 of said pail 102 with a threading 620 . In one embodiment, said threading 620 can comprise a sleeve threading 620 a and a lip threading 620 b.
[0037] FIGS. 7A and 7B illustrate a cross-section side view of a storable sleeve 702 stored inside said pail 102 and a cross-section side view of said storable sleeve 702 mounted externally of said lip 604 of said pail 102 .
[0038] In one embodiment, said storable sleeve 702 can be stored within said pail 102 during transport or when bucket storage system 100 is not in use. In one embodiment, said bucket storage system 100 can be setup by removing said storable sleeve 702 from said pail 102 , inverting said pail 102 , and fitting said storable sleeve 702 around said lip 604 . In one embodiment, said base 320 serves as a separation between said bucket cavity 302 and said sleeve cavity 404 . As a result, said sleeve cavity 404 can be elevated and provide ease of access to items placed within said sleeve cavity 404 .
[0039] FIGS. 8A and 8B illustrate a side view of said bucket storage system 100 and a cross-section side view of said bucket storage system 100 containing a one or more said ball 108 .
[0040] In one embodiment, said bucket storage system 100 can be set up as follows: removing said lid 104 from said pail 102 , placing said one or more ball 108 in said bucket cavity 302 , replacing said lid 104 if necessary for transport or storage, removing said lid 104 if reattached to said pail 102 , removing said one or more ball 108 from said bucket cavity 302 , attaching said lid 104 to said pail 102 , inverting said pail 102 , fitting said sleeve 106 on said pail 102 , and placing said one or more ball 108 in said sleeve cavity 404 .
[0041] FIGS. 9A and 9B illustrate a side view of said bucket storage system 100 in a lowest height configuration 902 and a side view of said bucket storage system 100 in a maximum height configuration 904 .
[0042] In one embodiment, said lid 104 can be rotateably adjusted on said pail 102 until said lid 104 is fully secured onto said pail 102 having said compacted height 304 . In one embodiment, said compacted height 304 and said sleeve height 406 add together to give said lowest height configuration 902 . In one embodiment, said lid 104 can be rotateably adjusted on said pail 102 to give said expanded height 314 . Said expanded height 314 coupled with said sleeve height 406 can equal said maximum height configuration 904 . In one embodiment, said bucket storage system 100 can be adjusted to provide a desired height between said lowest height configuration 902 and said maximum height configuration 904 .
[0043] FIGS. 10A, 10B and 10C illustrate a bucket storage system 1000 in a collapsed configuration 1010 , an exploded configuration 1012 , and an assembled configuration 1014 .
[0044] In one embodiment, said bucket storage system 1000 can comprise a pail 1002 , and a sleeve 1004 . In one embodiment, said pail 1002 can comprise a bottom rim 1006 and a base 1008 . In one embodiment, said bucket storage system 1000 can operate similar to said bucket storage system 100 , as illustrated and understood. In one embodiment, said bucket storage system 1000 can comprise a substantially rectangular shape as opposed to circular shape.
[0045] Various changes in the details of the illustrated operational methods are possible without departing from the scope of the following claims. Some embodiments may combine the activities described herein as being separate steps. Similarly, one or more of the described steps may be omitted, depending upon the specific operational environment the method is being implemented in. It is to be understood that the above description is intended to be illustrative, and not restrictive. For example, the above-described embodiments may be used in combination with each other. Many other embodiments will be apparent to those of skill in the art upon reviewing the above description. The scope of the invention should, therefore, be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. In the appended claims, the terms “including” and “in which” are used as the plain-English equivalents of the respective terms “comprising” and “wherein.”
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A bucket storage system is disclosed. The bucket storage system comprising a pail and a sleeve. The pail comprising a base and a sidewall. The pail contains a bucket cavity configured to store and hold sports equipment. The pail comprises a bottom diameter and a top diameter. The bucket cavity comprises a space above the base comprises and within the sidewall of the pail. The sleeve comprises a sidewall and a sleeve cavity. The sleeve comprises a upper sleeve diameter and a lower sleeve diameter. The upper sleeve diameter is greater in size than the lower sleeve diameter. The upper sleeve diameter is smaller than the top diameter of the pail.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a light emitting device comprising a plurality of pixels each having a light emitting element and a means for supplying current to the light emitting element.
2. Description of the Related Art
Since a light emitting element emits light by itself, it is highly visible and does not require a back light which is needed in a liquid crystal display device (LCD). Therefore, it is suitably applied to thin devices and not restricted in viewing angle. Because of these advantages, a light emitting device having a light emitting element has recently been drawing attentions as an alternative display device to a CRT and an LCD. It is to be noted that a light emitting element in this specification indicates an element whose luminance is controlled by current or voltage, and it includes an OLED (Organic Light Emitting Diode) or an MIM electron source element (electron discharge element) and the like which is used in an FED (Field Emission Display).
Also, a light emitting device of the invention includes a panel and a module obtained by mounting an IC or the like onto the panel. More generally, the invention relates to an element substrate which corresponds to the one before the completion of a panel in manufacturing steps of the light emitting device, and the element substrate comprises a plurality of pixels each having a means for supplying current to a light emitting element.
OLED which is one of the light emitting elements includes an anode layer, a cathode layer, and a layer containing an electric field light emitting material (hereinafter referred to as an electroluminescent layer) that generates luminescence (electroluminescence) when an electric field is applied thereto. The electroluminescent layer is provided between an anode and cathode, and it comprises a single or multiple layers. These layers may contain an inorganic compound. The electroluminescence in the electroluminescent layer includes a light emission (fluorescence) when a singlet exciting state returns to a ground state and a light emission (phosphorescence) when a triplet exciting state returns to a ground state.
Next, the configuration of a pixel of a general light emitting device and its drive will be described in brief. A pixel shown in FIG. 9 comprises a switching transistor 900 , a driving transistor 901 , a capacitor 902 , and a light emitting element 903 . The gate of the switching transistor 900 is connected to a scan line 905 . Either the source or drain of the switching transistor 900 is connected to a signal line 904 , and the other is connected to the gate of the driving transistor 901 . The source of the driving transistor 901 is connected to a power supply line 906 , and the drain of the driving transistor 901 is connected to the anode of the light emitting element 903 . The cathode of the light emitting element 903 is connected to a counter electrode 907 . The capacitor 902 is provided for storing a potential difference between the gate and source of the driving transistor 901 . Also, the predetermined voltages are applied to the power supply line 906 and the counter electrode 907 from a power supply and each has a potential difference.
When the switching transistor 900 is turned ON by a signal from the scan line 905 , a video signal that is inputted to the signal line 904 is inputted to the gate of the driving transistor 901 . The potential difference between a potential of the inputted video signal and that of the power supply line 906 corresponds to a gate-source voltage Vgs of the driving transistor 901 . Thus, current is supplied to the light emitting element 903 , and the light emitting element 903 emits light by using the supplied current.
SUMMARY OF THE INVENTION
A transistor using polysilicon has high field effect mobility and large on-current. Therefore, it is suited for a light emitting device. However, the transistor using polysilicon has problems in that it is likely to have variations in characteristics due to a defect in a crystal grain boundary.
In the pixel shown in FIG. 9 , when the magnitude of the drain current of the driving transistor 901 differs among pixels, the luminance intensity of the light emitting element 903 varies even with the same potential of a video signal.
As a means for controlling variations in drain current, there is a method for enlarging an L/W (L: channel length, W: channel width) of the driving transistor 901 as disclosed in Japanese Patent Application No. 2003-008719. The drain current Ids of the driving transistor 901 in a saturation region is expressed by the following formula 1.
Ids=â ( Vgs−Vth ) 2 /2 (formula 1)
It is apparent from the formula 1 that, the drain current Ids in the saturation region of the driving transistor 901 is easily fluctuated even by small variations in the gate-source voltage Vgs. Therefore, it is necessary to keep the gate-source voltage Vgs, which is stored between the gate and source of the driving transistor 901 , not to be varied while the light emitting element 901 emits light. Thus, storage capacity of the capacitor 902 which is disposed between the gate and source of the driving transistor 901 is required to be increased, and off-current of the switching transistor 900 is required to be suppressed low.
It is quite difficult to suppress off-current of the switching transistor 900 low, to increase on-current thereof for charging large capacitance, and to achieve both of them in the formation process of the transistor.
Also, there is another problem that the gate-source voltage Vgs of the driving transistor 901 is varied due to the switching of the switching transistor 900 , and potential changes in the signal line, scan line, and the like. This derives from the parasitic capacitance on the gate of the driving transistor 901 .
In view of the foregoing problems, the invention provides a light emitting device and an element substrate which are not easily influenced by parasitic capacitance and capable of suppressing variations in luminance intensity of the light emitting element 903 among pixels due to characteristic variations of the driving transistor 901 without suppressing off-current of the switching transistor 900 low and increasing storage capacity of the capacitor 902 .
According to the invention, a depletion mode transistor is used as a driving transistor. The gate of the driving transistor is fixed in its potential or connected to the source or drain thereof to operate in a saturation region with a constant current flow. Also, a current controlling transistor which operates in a linear region is connected in series to the driving transistor. A video signal for transmitting a light emission or non-emission of a pixel is inputted to the gate of the current controlling transistor through a switching transistor.
Transistors other than the driving transistor are normal enhancement mode transistors here.
Since the current controlling transistor operates in a linear region, its source-drain voltage Vds is small, and small changes in a gate-source voltage Vgs of the current controlling transistor do not influence the current flowing in a light emitting element. Current flowing in the light emitting element is determined by the driving transistor which operates in a saturation region.
Current flowing in the light emitting element is not influenced even without increasing storage capacity of a capacitor which is disposed between the gate and source of the current controlling transistor or suppressing off-current of the switching transistor low. In addition, it is not influenced by the parasitic capacitance on the gate of the current controlling transistor either. Therefore, cause of variation is decreased, and image quality is thus enhanced to a great extent.
In addition, as there is no need to suppress off-current of the switching transistor low, manufacturing process of the transistor can be simplified, thus contributes greatly to the cost reduction and improvement in yield.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagram showing an embodiment mode of the invention.
FIG. 2 is a diagram showing an embodiment mode of the invention.
FIG. 3 is a diagram showing an embodiment mode of the invention.
FIG. 4 is a diagram showing an embodiment mode of the invention.
FIG. 5 is a schematic view showing an external circuit and a panel.
FIG. 6 is a diagram showing the configuration example of a signal driver circuit.
FIG. 7 is an example showing a top plan view of the invention.
FIGS. 8A to 8D are examples showing electronic apparatuses to which the invention is applied.
FIG. 9 is a diagram of an embodiment.
FIG. 10 is an example showing a top plan view of the invention.
FIGS. 11A and 11B are examples showing cross-sectional structures of the invention.
FIG. 12 is an example showing the operation timing of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Embodiment modes of the invention are described in detail with reference to the accompanying drawings below.
Embodiment Mode 1
FIG. 1 shows an embodiment mode of a pixel of the light emitting device of the invention. The pixel shown in FIG. 1 comprises a light emitting element 104 , a transistor (switching transistor) 101 used as a switching element for controlling an input of a video signal to the pixel, a driving transistor 102 for controlling current flowing in the light emitting element 104 , and a current controlling transistor 103 for controlling a current supply to the light emitting element 104 . In addition, it is also possible to dispose in the pixel a capacitor 105 for storing a potential of a video signal.
The driving transistor 102 and the current controlling transistor 103 have the same conductivity. It is assumed that the driving transistor 102 is a depletion mode transistor, and the rest of the transistors are normal enhancement mode transistors. In the invention, the driving transistor 102 is operated in a saturation region and the current controlling transistor 103 is operated in a linear region.
The channel length (L) of the driving transistor 102 may be longer than its channel width (W), and L of the current controlling transistor 103 may be equal to or shorter than its W. Desirably, the ratio of L to W (L/W) of the driving transistor 102 is five or more.
The gate of the switching transistor 101 is connected to a scan line Gj (j=1 to y). Either the source or drain of the switching transistor 101 is connected to a signal line Si (i=1 to x), and the other is connected to the gate of the current controlling transistor 103 . The gate of the driving transistor 102 is connected to a power supply line Vi (i=1 to x). The driving transistor 102 and the current controlling transistor 103 are each connected to the power supply line Vi (i=1 to x) and the light emitting element 104 so that a current supplied from the power supply line Vi (i=1 to x) is supplied to the light emitting element 104 as a drain current of the driving transistor 102 and of the current controlling transistor 103 . In this embodiment mode, the source of the current controlling transistor 103 is connected to the power supply line Vi i=1 to x) and the drain of the driving transistor 102 is connected to a pixel electrode of the light emitting element 104 .
It is to be noted that the source of the driving transistor 102 may be connected to the power supply line Vi (i=1 to x), and the drain of the current controlling transistor 103 may be connected to the pixel electrode of the light emitting element 104 .
The light emitting element 104 comprises an anode, a cathode, and a light emitting layer interposed between the anode and cathode. As shown in FIG. 1 , when the anode of the light emitting element 104 is connected to the driving transistor 102 , the anode is a pixel electrode and the cathode is a counter electrode. The counter electrode of the light emitting element 104 and the power supply line Vi (i=1 to x) are made to have a potential difference so that current flows into the light emitting element 104 in the forward bias direction.
One of the two electrodes of the capacitor 105 is connected to the power supply line Vi (i =1 to x), and the other is connected to the gate of the current controlling transistor 103 . The capacitor 105 is disposed so as to store a potential difference between the two electrodes of the capacitor 105 when the switching transistor 101 is not selected (off state). It is to be noted that although FIG. 1 shows a configuration disposing the capacitor 105 , the invention is not limited to this and an alternative configuration without the capacitor 105 may be employed as well.
In FIG. 1 , each of the driving transistor 102 and the current controlling transistor 103 is a P-type transistor, and the drain of the driving transistor 102 is connected to the anode of the light emitting element 104 . On the contrary, in the case where each of the driving transistor 102 and the current controlling transistor 103 is an N-type transistor, the source of the driving transistor 102 is connected to the cathode of the light emitting element 104 . In this case, the cathode of the light emitting element 104 is a pixel electrode and the anode thereof is a counter electrode.
Next, a driving method of the pixel shown in FIG. 1 is described. The operation of the pixel shown in FIG. 1 can be divided into a writing period and a data storage period. First, in the writing period, when the scan line Gj (j=1 to y) is selected, the switching transistor 101 whose gate is connected to the scan line Gj (j=1 to y) is turned ON. Then, a video signal which is inputted to the signal line Si (i=1 to x) is inputted to the gate of the current controlling transistor 103 through the switching transistor 101 . The driving transistor 102 is ON at all times as its gate is connected to the power supply line Vi (i=1 to x).
When the current controlling transistor 103 is turned ON by a video signal, current is supplied to the light emitting element 104 through the current supply line Vi (i=1 to x). At this time, the current controlling transistor 103 operates in a linear region, thus current flowing in the light emitting element 104 is determined by volt-ampere characteristics of the driving transistor 102 operating in a saturation region and the light emitting element 104 . The light emitting element 104 emits light at luminance corresponding to the magnitude of the supplied current.
Meanwhile, when the current controlling transistor 103 is turned OFF by a video signal, no current is supplied to the light emitting element 104 , thus it does not emit light. It is to be noted that according to the invention, it is possible to control current not to be supplied to the light emitting element 104 even when the driving transistor 102 is a depletion mode transistor since the current controlling transistor 103 is an enhancement mode transistor.
In the data storage period, the switching transistor 101 is turned OFF by controlling a potential of the scan line Gj (j=1 to y), thereby storing a potential of the video signal that is written in the writing period. In the writing period, when the current controlling transistor 103 is turned ON, a potential of a video signal is stored in the capacitor 105 , therefore, the current supply to the light emitting element 104 is kept on. On the contrary, when the current controlling transistor 103 is turned OFF in the writing period, a potential of a video signal is stored in the capacitor 105 , therefore, current is not supplied to the light emitting element 104 .
An element substrate of the invention corresponds to the one before the formation of a light emitting element in manufacturing steps of the light emitting device of the invention.
A transistor used in the light emitting device of the invention may be a transistor formed by using single crystalline silicon or an SOI, a thin film transistor using polycrystalline silicon or amorphous silicon, or a transistor using an organic semiconductor or a carbon nanotube. In addition, a transistor disposed in a pixel of the light emitting device of the invention may be a single gate transistor, a double gate transistor, or a multi-gate transistor having more than two gate electrodes.
According to the above-described configuration, a source-drain voltage Vds of the current controlling transistor 103 is small as the current controlling transistor 103 operates in a linear region, therefore, small changes in the gate-source voltage Vgs of the current controlling transistor 103 do not influence the current flowing in a light emitting element 104 . Current flowing in the light emitting element 104 is determined by the driving transistor 102 which operates in a saturation region. Current flowing in the light emitting element 104 is not influenced even without increasing storage capacity of the capacitor 105 which is disposed between the gate and source of the current controlling transistor 103 or suppressing off-current of the switching transistor 101 low. In addition, it is not influenced by the parasitic capacitance on the gate of the current controlling transistor 103 either. Therefore, cause of variation is decreased, and image quality is thus enhanced to a great extent.
Embodiment Mode 2
Described in this embodiment mode is a different configuration of a pixel of the light emitting device from that shown in FIG. 1 .
The pixel shown in FIG. 2 comprises a light emitting element 204 , a switching transistor 201 , a driving transistor 202 , a current controlling transistor 203 , and a transistor (erasing transistor) 206 for turning OFF the current controlling transistor 203 forcibly. In addition, it is also possible to dispose a capacitor 205 in addition to the aforementioned elements.
The driving transistor 202 and the current controlling transistor 203 have the same conductivity. The size, characteristics, and operating region of each transistor may be set in the same manner as Embodiment Mode 1.
The gate of the switching transistor 201 is connected to a first scan line Gaj (j=1 to y). Either the source or drain of the switching transistor 201 is connected to a signal line Si (i=1to x), and the other is connected to the gate of the current controlling transistor 203 . The gate of the erasing transistor 206 is connected to a second scan line Gej (j=1 to y). Either the source or drain of the erasing transistor 206 is connected to a power supply line Vi (i=1to x), and the other is connected to the gate of the current controlling transistor 203 . The gate of the driving transistor 202 is connected to the power supply line Vi (i=1 to x). The driving transistor 202 and the current controlling transistor 203 are each connected to the power supply line Vi (i=1 to x) and the light emitting element 204 so that a current supplied from the power supply line Vi (i=1 to x) is supplied to the light emitting element. 204 as a drain current of the driving transistor 202 and of the current controlling transistor 203 . In this embodiment mode, the source of the current controlling transistor 203 is connected to the power supply line Vi (i=1 to x) and the drain of the driving transistor 202 is connected to a pixel electrode of the light emitting element 204 .
It is to be noted that the source of the driving transistor 202 may be connected to the power supply line Vi (i=1 to x), and the drain of the current controlling transistor 203 may be connected to the pixel electrode of the light emitting element 204 .
The light emitting element 204 comprises an anode, a cathode, and a light emitting layer interposed between the anode and cathode. As shown in FIG. 2 , when the anode of the light emitting element 204 is connected to the driving transistor 202 , the anode is a pixel electrode and the cathode is a counter electrode. The counter electrode of the light emitting element 204 and the power supply line Vi (i=1 to x) have a potential difference so that current flows into the light emitting element 204 in the forward bias direction.
One of the two electrodes of the capacitor 205 is connected to the power supply line Vi (i=1 to x), and the other is connected to the gate of the current controlling transistor 203 .
In FIG. 2 , each of the driving transistor 202 and the current controlling transistor 203 is a P-type transistor, and the drain of the driving transistor 202 is connected to the anode of the light emitting element 204 . On the contrary, in the case where each of the driving transistor 202 and the current controlling transistor 203 is an N-type transistor, the source of the driving transistor 202 is connected to the cathode of the light emitting element 204 . In this case, the cathode of the light emitting element 204 is a pixel electrode and the anode thereof is a counter electrode.
The operation of the pixel shown in FIG. 2 can be divided into a writing period, a data storage period, and an erasing period. The operations of the switching transistor 201 , the driving transistor 202 , and the current controlling transistor 203 in writing period and data storage period are the same as those in FIG. 1 .
In erasing period, the second scan line Gaj (j=1 to y) is selected to turn ON the erasing transistor 206 , thus a potential of the power supply line Vi (i=1 to x) is supplied to the gate of the current controlling transistor 203 through the erasing transistor 206 . Therefore, the current controlling transistor 203 is turned OFF, and the light emitting element 204 can be forcibly brought into the state where no current is supplied.
Embodiment Mode 3
Described in this embodiment mode is a different configuration of a pixel of the light emitting device of the invention from those of Embodiment Modes 1 and 2.
The pixel shown in FIG. 3 comprises a light emitting element 304 , a transistor (switching transistor) 301 used as a switching element for controlling input of a video signal to the pixel, a driving transistor 302 for controlling a current flowing into the light emitting element 304 , a current controlling transistor 303 for controlling a current supply to the light emitting element 304 . In addition, it is also possible to dispose a capacitor 305 for storing a potential of a video signal as shown in the figure.
The driving transistor 302 and the current controlling transistor 303 have the same conductivity. The size, characteristics, and operating region of each transistor may be set in the same manner as those of Embodiment Mode 1.
The gate of the switching transistor 301 is connected to a scan line Gj (j=1 to y). Either the source or drain of the switching transistor 301 is connected to a signal line Si (i=1to x), and the other is connected to the gate of the current controlling transistor 303 . The gate of the driving transistor 302 is connected to the source thereof. The driving transistor 302 and the current controlling transistor 303 are each connected to a power supply line Vi (i=1 to x) and the light emitting element 304 so that a current supplied from the power supply line Vi (i=1 to x) is supplied to the light emitting element 304 as a drain current of the driving transistor 302 and of the current controlling transistor 303 . In this embodiment mode, the source of the current controlling transistor 303 is connected to the power supply line Vi (i=1 to x) and the drain of the driving transistor 302 is connected to a pixel electrode of the light emitting element 304 .
It is to be noted that the source and gate of the driving transistor 302 may be connected to the power supply line Vi (i=1 to x), and the drain of the current controlling transistor 303 may be connected to the pixel electrode of the light emitting element 304 .
The light emitting element 304 comprises an anode, a cathode, and a light emitting layer interposed between the anode and cathode. As shown in FIG. 3 , when the anode of the light emitting element 304 is connected to the driving transistor 302 , the anode is a pixel electrode and the cathode is a counter electrode. The counter electrode of the light emitting element 304 and the power supply line Vi (i=1 to x) have a potential difference so that current flows into the light emitting element 304 in the forward bias direction.
One of the two electrodes of the capacitor 305 is connected to the power supply line Vi (i=1 to x), and the other is connected to the gate of the current controlling transistor 303 . The capacitor 305 is disposed so as to store a potential difference between the two electrodes of the capacitor 305 when the switching transistor 301 is not selected (off state). It is to be noted that although FIG. 3 shows a configuration disposing the capacitor 305 , the invention is not limited to this and an alternative configuration without the capacitor 305 may be employed as well.
In FIG. 3 , each of the driving transistor 302 and the current controlling transistor 303 is a P-type transistor, and the drain of the driving transistor 302 is connected to the anode of the light emitting element 304 . On the contrary, in the case where each of the driving transistor 302 and the current controlling transistor 303 is an N-type transistor, the source of the driving transistor 302 is connected to the cathode of the light emitting element 304 . In this case, the cathode of the light emitting element 304 is a pixel electrode and the anode thereof is a counter electrode.
The operation of the pixel shown in FIG. 3 is the same as that shown in FIG. 1 .
Embodiment Mode 4
Described in this embodiment mode is a different configuration of a pixel of the light emitting device of the invention from those of Embodiment Modes 1 to 3.
The pixel shown in FIG. 4 comprises a light emitting element 404 , a switching transistor 401 , a driving transistor 402 , a current controlling transistor 403 , and a transistor (erasing transistor) 406 for erasing a potential of a written video signal. It is also possible to dispose a capacitor 405 in addition to the above elements.
The driving transistor 402 and the current controlling transistor 403 have the same conductivity. The size, characteristics, and operating region of each transistor may be set in the same manner as those of Embodiment Mode 1.
The gate of the switching transistor 401 is connected to a first scan line Gaj (j=1 to y). Either the source or drain of the switching transistor 401 is connected to a signal line Si (i=1to x), and the other is connected to the gate of the current controlling transistor 403 . The gate of the erasing transistor 406 is connected to a second scan line Gaj (j=1 to y). Either the source or drain of the erasing transistor 406 is connected to a second scan line Gaj (i=1to x), and the other is connected to the gate of the current controlling transistor 403 . The gate of the driving transistor 402 is connected to the source thereof. The driving transistor 402 and the current controlling transistor 403 are each connected to a power supply line Vi (i=1 to x) and the light emitting element 404 so that a current supplied from the power supply line Vi (i=1 to x) is supplied to the light emitting element 404 as a drain current of the driving transistor 402 and of the current controlling transistor 403 . In this embodiment mode, the source of the current controlling transistor 403 is connected to the power supply line Vi (i=1 to x) and the drain of the driving transistor 402 is connected to a pixel electrode of the light emitting element 404 .
It is to be noted that the source of the driving transistor 402 may be connected to the power supply line Vi (i=1 to x), and the drain of the current controlling transistor 403 may be connected to the pixel electrode of the light emitting element 404 .
The light emitting element 404 comprises an anode, a cathode, and a light emitting layer interposed between the anode and cathode. As shown in FIG. 4 , when, the anode of the light emitting element 404 is connected to the driving transistor 402 , the anode is a pixel electrode and the cathode is a counter electrode. The counter electrode of the light emitting element 404 and the power supply line Vi (i=1 to x) have a potential difference so that current flows into the light emitting element 404 in the forward bias direction.
One of the two electrodes of the capacitor 405 is connected to the power supply line Vi (i=1 to x), and the other is connected to the gate of the current controlling transistor 403 .
In FIG. 4 , each of the driving transistor 402 and the current controlling transistor 403 is a P-type transistor, and the drain of the driving transistor 402 is connected to the anode of the light emitting element 404 . On the contrary, in the case where each of the driving transistor 402 and the current controlling transistor 403 is an N-type transistor, the source of the driving transistor 402 is connected to the cathode of the light emitting element 404 . In this case, the cathode of the light emitting element 404 is a pixel electrode and the anode thereof is a counter electrode.
The operation of the pixel shown in FIG. 4 is the same as that shown in FIG. 2 .
In addition, either an N-type transistor or a P-type transistor may be employed as a switching transistor and an erasing transistor used in the invention.
Embodiment 1
Described in this embodiment are a configuration of an active matrix display device to which the pixel configuration of the invention is applied and its drive.
FIG. 5 shows a block diagram of an external circuit and a schematic view of a panel.
An active matrix display device shown in FIG. 5 comprises an external circuit 5004 and a panel 5010 . The external circuit 5004 comprises an A/D converter unit 5001 , a power supply unit 5002 , and a signal generator unit 5003 . The A/D converter unit 5001 converts an image data signal which is inputted as an analog signal into a digital signal (video signal), and supplies it to a signal driver circuit 5006 . The power supply unit 5002 generates power having a predetermined voltage from the power supplied from a battery or an outlet, and supplies it to the signal driver circuit 5006 , scan driver circuits 5007 , an OLED 5011 , the signal generator unit 5003 , and the like. The signal generator unit 5003 is inputted with power, an image signal, a synchronizing signal, and the like. Also, it generates a clock signal and the like for driving the signal driver circuit 5006 and the scan driver circuits 5007 .
A signal and power from the external circuit 5004 are inputted to an internal circuit and the like through an FPC and an FPC connection portion 5005 in the panel 5010 .
The pixel 5010 comprises a substrate 5008 mounting the FPC connection portion 5005 , the internal circuit, and the OLED 5011 . The internal circuit comprises the signal driver circuit 5006 , the scan driver circuits 5007 , a pixel portion 5009 . Although FIG. 5 employs the pixel shown in Embodiment Mode 1, an alternative pixel configuration shown in other embodiment modes of the invention may be employed as well.
The pixel portion 5009 is disposed in the center of the substrate, and the signal driver circuit 5006 and the scan driver circuit 5007 are disposed on the periphery of the pixel portion 5009 . The OLED 5011 and a counter electrode of the OLED are formed over the pixel portion 5009 .
FIG. 6 shows a more detailed block diagram of the signal driver circuit 5006 .
The signal driver circuit 5006 comprises a shift register 6002 including a plurality of stages of D-flip flops 6001 , a data latch circuit 6003 , a latch circuit 6004 , a level shifter 6005 , a buffer 6006 , and the like.
It is assumed that a clock signal (S-CK), an inverted clock signal (S-CKB), a start pulse (S-SP), a video signal (DATA), and a latch pulse (LatchPulse) are inputted.
First, in accordance with a clock signal, an inverted clock signal, and a start pulse, a sampling pulse is sequentially outputted from the shift register 6002 . In accordance with the timing in which the sampling pulse is inputted to the data latch circuit 6003 , a video signal is sampled and thus stored. This operation is sequentially performed from the first column.
When the storage of a video signal is completed in the data latch circuit 6003 on the last stage, a latch pulse is inputted during a horizontal retrace period, and the video signal stored in the data latch circuit 6003 is transferred to the latch circuit 6004 all at once. Then, it is level-shifted in the level shifter 6005 , and adjusted in the buffer 6006 so as to be outputted to signal lines S 1 to Sn all at once. At this time, an H-level or an L-level signal is inputted to pixels in the row selected by the scan driver circuits 5007 , thereby controlling a light emission or non-emission of the OLED 5011 .
Although the active matrix display device shown in this embodiment comprises the panel 5010 and the external circuit 5004 each formed independently, they may be integrally formed on the same substrate. Also, although the display device employs. OLED in this embodiment, other light emitting elements can be employed as well. In addition, the level shifter 6005 and the buffer 6006 may not necessarily be provided in the signal driver circuit 5006 .
Embodiment 2
Described in this embodiment is a top plan view of the pixel shown in FIG. 2 . FIG. 7 shows a top plan view of a pixel of this embodiment.
Reference numeral 7001 denotes a signal line, 7002 denotes a power supply line, 7004 denotes a first scan line, and 7003 denotes a second scan line. In this embodiment, the signal line 7001 and the power supply line 7002 are formed of the same conductive film, and the first scan line 7004 and the second scan line 7003 are formed of the same conductive film. Reference numeral 7005 denotes a switching transistor, and a part of the first scan line 7004 functions as its gate electrode. Reference numeral 7006 denotes an erasing transistor, and a part of the second scan line 7003 functions as its gate electrode. Reference numeral 7007 denotes a driving transistor, and 7008 denotes a current controlling transistor. An active layer of the driving transistor 7007 is curved so that its L/W becomes larger than that of the current controlling transistor 7008 . Reference numeral 7009 denotes a pixel electrode, and light is emitted in its overlapped area (light emitting area) 7010 with a light emitting layer and a cathode (neither of them is shown).
It is to be noted that the top plan view of the invention shown in this embodiment is only an example, and the invention is, needless to say, not limited to this.
Embodiment 3
Described in this embodiment is an example of a top plan view of the pixel shown in FIG. 2 , which is different from that shown in FIG. 7 . FIG. 10 shows a top plan view of a pixel of this embodiment.
Reference numeral 10001 denotes a signal line, 10002 denotes a power supply line, 10004 denotes a first scan line, and 10003 denotes a second scan line. In this embodiment, the signal line 10001 and the power supply line 10002 are formed of the same conductive film, and the first scan line 10004 and the second scan line 10003 are formed of the same conductive film. Reference numeral 10005 denotes a switching transistor, and a part of the first scan line 10004 functions as its gate electrode. Reference numeral 10006 denotes a erasing transistor, and a part of the second scan line 10003 functions as its gate electrode. Reference numeral 10007 denotes a driving transistor, and 10008 denotes a current controlling transistor. An active layer of the driving transistor 10007 is curved so that its L/W becomes larger than that of the current controlling transistor 10008 . Reference numeral 10009 denotes a pixel electrode, and light is emitted in its overlapped area (light emitting area) 10010 with a light emitting layer and a cathode (neither of them is shown).
It is to be noted that the top plan view of this embodiment is only an example, and the invention is, needless to say, not limited to this.
Embodiment 4
Described in this embodiment is a cross-sectional structure of a pixel.
FIG. 11A shows a cross-sectional view of a pixel in which a driving transistor 11021 is a P-type transistor and light emitted from a light emitting element 11022 is transmitted to an anode side 11023 . In FIG. 11A , the anode 11023 of the light emitting element 11022 is electrically connected to the driving transistor 11021 , and a light emitting layer 11024 and a cathode 11025 are laminated on the anode 11023 in this order. As for the cathode 11025 , known material can be used as long as it is a conductive film having a small work function and reflecting light. For example, Ca, Al, CaF, MgAg, AlLi, and the like are desirably used. The light emitting layer 11024 may comprise a single layer or multiple layers. When it comprises multiple layers, a hole injection layer, a hole transporting layer, a light emitting layer, an electron transporting layer, and an electron injection layer are sequentially laminated in this order on the cathode 11023 . It is to be noted that not all of the above layers are necessarily provided. The anode 11023 may be formed of a transparent conductive film which transmits light, such as the one comprising ITO or the one in which indium oxide is mixed with zinc oxide (ZnO) of 2 to 20%.
The overlapped portion of the anode 11023 , the light emitting layer 11024 , and the cathode 11025 corresponds to the light emitting element 11022 . In the case of the pixel shown in FIG. 11A , light emitted from the light emitting element 11022 is transmitted to the anode 11023 side as shown by an outline arrow.
FIG. 11B shows a cross-sectional view of a pixel in which a driving transistor 11001 is an N-type transistor and light emitted from a light emitting element 11002 is transmitted to an anode side 11005 . In FIG. 11B , a cathode 11003 of the light emitting element 11002 is electrically connected to the driving transistor 11001 , and a light emitting layer 11004 and an anode 11005 are laminated on the cathode 11003 in this order. As for the cathode 11005 , known material can be used as long as it is a conductive film having a small work function and reflecting light. For example, Ca, Al, CaF, MgAg, AlLi, and the like are desirably used. The light emitting layer 11004 may comprise a single layer or multiple layers. When it comprises multiple layers, a hole injection layer, a hole transporting layer, a light emitting layer, an electron transporting layer, and an electron injection layer are sequentially laminated in this order on the cathode 11003 . It is to be noted that not all the above layers are necessarily provided. The anode 11005 may be formed of a transparent conductive film which transmits light, such as the one comprising ITO or the one in which indium oxide is mixed with zinc oxide (ZnO) of 2 to 20%.
The overlapped portion of the anode 11003 , the light emitting layer 11004 , and the cathode 11005 corresponds to the light emitting element 11002 . In the case of the pixel shown in FIG. 11B , light emitted from the light emitting element 11002 is transmitted to the anode 11003 side as shown by an outline arrow.
It is to be noted that although shown in this embodiment is the one in which a driving transistor is electrically connected to a light emitting element, a current controlling transistor may be interposed between the driving transistor and the light emitting element.
Embodiment 5
Described in this embodiment is an example of the drive timing where the pixel configuration of Embodiment Mode 2 is employed.
FIG. 12A shows an example using a digital time gray scale method for a 4-bit gray scale display. In data storage periods Ts 1 to Ts 4 , the ratio of the time length is assumed to be Ts 1 :Ts 2 :Ts 3 :Ts 4 =2 3 :2 2 :2 1 :2 0 =4:2:1.
The operation is described next. First, in a writing period Tb 1 , the first scan line is selected from the first row in sequence, thereby turning ON the switching transistor. Next, a video signal is inputted to each pixel from a signal line, thereby controlling a light emission or non-light emission of each pixel according to a potential of the signal. Once the video signal is written, that row proceeds to the data storage period Ts 1 immediately. The same operation is performed up to the last row, and thus a period Ta 1 terminates. Subsequently, a writing period Tb 2 is started from the row in which the data storage period Ts 1 is complete in sequence.
In the sub-frame period having the shorter data storage period than the writing period (corresponds to a period Ta 4 here), an erasing period 2102 is provided so that a next writing period is not started immediately after the data storage period. In the erasing period, a light emitting element is forced to be in a non-emission state.
Taken as an example here is the case of expressing a 4-bit gray scale display, however the number of bits and gray scales is not limited to this. In addition, light emission is not necessarily performed from Ts 1 to Ts 4 in sequence. It may be performed at random, or divided into a plurality of periods.
Embodiment 6
The display device of the invention can be used in display portions of various electronic apparatuses. In particular, the display device of the invention is desirably applied to a mobile device that requires low power consumption.
Electronic apparatuses using the display device of the invention include a portable information device (a cellular phone, a mobile computer, a portable game machine, an electronic book, and the like), a video camera, a digital camera, a goggle display, a display device, a navigation system, and the like. Specific examples of these electronic apparatuses are shown in FIGS. 8A to 8D .
FIG. 8A shows a display device which includes a housing 8001 , an audio output portion 8002 , a display portion 8003 , and the like. The display device of the invention can be used for the display portion 8003 . Note that, the display device includes all the information display devices for personal computers, television broadcast reception, advertisement displays, and the like.
FIG. 8B shows a mobile computer which includes a main body 8101 , a stylus 8102 , a display portion 8103 , operation keys 8104 , an external interface 8105 , and the like. The display device of the invention can be used for the display portion 8103 .
FIG. 8C shows a game machine which includes a main body 8201 , a display portion 8202 , operation keys 8203 , and the like. The display device of the invention can be used for the display portion 8202 .
FIG. 8D shows a cellular phone which includes a main body 8301 , an audio output portion 8302 , a display portion 8304 , operation switches 8305 , an antenna 8306 , and the like. The display device of the invention can be used for the display portion 8304 .
As described above, an application range of the invention is so wide that the invention can be applied to electronic apparatuses in various fields.
Although the invention has been fully described by way of example with reference to the accompanying drawings, it is to be understood that various modifications will be apparent to those skilled in the art. Therefore, unless otherwise such changes and modifications depart from the scope of the invention hereinafter defined, they should be constructed as being included therein.
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A light emitting device and an element substrate which are capable of suppressing variations in the luminance intensity of a light emitting element among pixels due to characteristic variations of a driving transistor without suppressing off-current of a switching transistor low and increasing storage capacity of a capacitor. According to the invention, a depletion mode transistor is used as a driving transistor. The gate of the driving transistor is fixed in its potential or connected to the source or drain thereof to operate in a saturation region with a constant current flow. A current controlling transistor which operates in a linear region is connected in series to the driving transistor, and a video signal for transmitting a light emission or non-emission of a pixel is inputted to the gate of the current controlling transistor through a switching transistor.
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FIELD OF THE INVENTION
[0001] The invention relates to medicine, namely to endocrinology, andrology, in particular, the invention refers to the use of ipidacrine for the treatment of disorders of potency and other forms of sexual activity.
BACKGROUND OF THE INVENTION
[0002] Some pharmaceutical formulations containing ipidacrine (Axamon, Amiridine, Neyromidin) are well known, but these formulations are intended for the use as drug products for the treatment of other diseases, namely diseases of the peripheral nervous system (PNS) including (mono-and polyneuropathy) polyradiculopaty, myasthenia and Eaton-Lambert syndrome of various etiologies); diseases of the central nervous system (CNS), including bulbar paralysis and paresis; for the use in the recovery period in case of organic lesions of the central nervous system accompanied by motor and/or cognitive impairment); intestinal atony (treatment and prevention).
[0003] Therefore, the use of pharmaceutical formulations containing ipidacrine for the treatment of disorders of potency and other forms of sexual activity is proposed by the authors for the first time.
OBJECTS OF THE INVENTION
[0004] The invention can be applied in the clinic for the treatment of potency disorders associated with the decreased production of hormones by the sex glands; disorders caused by chronic (including physical) stress as well as against the background of spontaneously reduced sexual function including manifested anorgasmia or delayed ejaculation, other disorders of sexual activity which do not limit the scope of the invention.
[0005] The object of the present invention is to extend the use of ipidacrine for the treatment of sexual dysfunction associated with the decreased production of hormones by the sex glands, chronic stress as well as manifested anorgasmia or delayed ejaculation as well as the creation of a new pharmaceutical formulation containing ipidacrine which would expand the use of ipidacrine in pharmaceutical formulations and provide the use of ipidacrine in pharmaceutical formulations for the treatment of sexual activity disorders associated with reduced production of hormones by the sex glands; disorders caused by chronic (including physical) stress as well as against the background of the spontaneously reduced sexual function including manifested anorgasmia or delayed ejaculation.
SUMMARY OF THE INVENTION
[0006] Ipidacrine is a reversible cholinesterase inhibitor. Four classes of cholinesterase inhibitors are known (aminopyridines, organophosphates, carbamates and all the rest). Ipidacrine is an aminopyridine that possesses the structural similarity with the other known aminopyridine, namely tacrine, but is superior to the last in relation to the efficacy and safety (Kojima et al., 1998). Cholinesterases are enzymes that carry out the inactivation of acetylcholine. In turn, acetylcholine is the main neurotransmitter responsible for the conduction of excitement in the peripheral nervous system, maintenance of neuromuscular transmission, increased contractility and tone of smooth muscle organs; it also produces a stimulating effect on the central nervous system. Thus, the inhibition of cholinesterase activity leads to the maintenance of the acetylcholine level and corresponding activity of neuroregulatory functions.
[0007] It is known that the sexual function is controlled by neuronal, neuroendocrine, endocrine and neurotransmitter systems. The cholinergic system is involved in the sexual behavior via the M-cholinergic mechanism that transmits non-specific information to the neocortex from subcortical structures (reticular formation, hypothalamus) and in the functioning of the cortical “awakening” system. The cholinesterase inhibitors affect the neuroregulatory processes including those accompanying sexual behavior. For example, in vivo experiments demonstrated that the introduction of the cholinesterase inhibitor (eserine) into the lateral ventricle in the brain increases the lordosis in ovariectomized, hypoestrogenic rats (Clemens et al., 1989). The authors also demonstrate the influence of the other cholinesterase inhibitor, acetylcholine, to enhance the sexual receptivity of the animals. The performed experiments prove that sexual behavior is regulated, among others, via endogenous cholinergic activity.
[0008] Similar effects of enhancing sexual behavior in animals when administering cholinesterase inhibitors are demonstrated in a number of other experiments (Clemens et al., 1980; Dohanich et al., 1990; Menard & Dohanich, 1994; Dohanich & Clemens, 1981).
[0009] In vivo studies showed that against the background of different external stimuli, such as memorizing or learning, stress, any research, and other exposures that directly or indirectly affect the brain activity, the increase in the acetylcholine level is observed, and its level may vary depending on the type of external exposure. (Mitsushima, 2010). The experiment demonstrated that against the background of sexual exposure, an increase in the level of acetylcholine occurs, therefore, this neurotransmitter performs one of the most important neuroregulatory functions influencing the sexual behavior and functions. It can be concluded that the inhibitors of cholinesterase (which negates the action of acetylcholine) are advisable to use for improvement of all components providing the neuroregulatory basis of sexual activity.
[0010] The indirect indication of the effect of cholinesterase inhibitors on the enhancement of sexual behavior is also side effects of the use of the drugs of this class in the treatment of patients with dementia. For example, when the drug donepezil (cholinesterase inhibitor) is given to patients in the treatment of Alzheimer's disease, an increase in the sexual behavior in these patients, even to the manifestation of sexual aggression is observed (Bianchetti et al., 2003; Bouman & Pinner, 1998; Lo Coco & Cannizzaro, 2010).
[0011] Thus, the regulation of the sexual behavior via cholinergic mechanisms is carried out in the central level. The clinical forms of sexual dysfunction are psychogenic and stressor disorders of the sexual function as well as disorders associated with the damage of the central and peripheral nervous system and associated with decreased levels of sex hormones. For this reason, the drugs from the group of cholinesterase inhibitors may be used in the treatment of the specified disorders.
BRIEF DESCRIPTION OF DRAWINGS
[0012] FIG. 1 shows the effect of the drugs to be compared on the sexual activity (mean number of ejaculations) of hemigonadectomized rats when administering the drugs in mean therapeutic doses in the course of treatment.
[0013] FIG. 2 presents the effect of ipidacrine on the sexual activity of male rats using the model of chronic stress caused by electrical current exposure.
[0014] FIG. 3 shows the effect of ipidacrine on the sexual activity of rats using the model of spontaneous sexual dysfunction (by criterion of the number of ejaculations)
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Definitions
[0015] The term “pharmaceutical formulation” means a formulation in tablet or capsule form (as an example but not limited to hard gelatin capsules), including that of prolonged action, containing ipidacrine as a main biologically active substance in an effective amount from 3 to 300 mg per dose and additionally containing the pharmaceutically acceptable excipients.
[0016] The term “pharmaceutically acceptable excipient” means a substance needed to improve tableting, such as, but not limited to, hydroxypropyl methylcellulose, microcrystalline cellulose, colloidal silicon dioxide, magnesium stearate and other conventional pharmaceutical excipients which do not limit the scope of the invention.
Embodiments of invention
[0017] To illustrate the effects of pharmaceutical formulations based on ipidacrine, here in are the following examples which do not limit the scope of the invention.
Example 1
[0018] Preparation of pharmaceutical formulations containing ipidacrine.
[0019] The pharmaceutical tableted formulations (including those of prolonged action) on the basis of ipidacrine are made in a standard way of direct compression. All the ingredients (except magnesium stearate) are stirred to obtain a homogeneous powder mixture using a Y-shaped mixer or similar equipment. Then magnesium stearate is added, and the resulting mixture is stirred for 2 minutes. The obtained tablet mass is subjected to a tableting process (tablet diameter of 10 mm or 11 mm in accordance with industry standard OST 64-072-89, with a scoreline and bevel edge) at a pressing force of 9-10 kN.
[0020] Pharmaceutical formulations in capsules are made using standard processing methods by mixing active ingredients and excipients in the correct proportion and further encapsulation.
[0021] Pharmaceutical Formulation 1 (Content for 1 Tablet of 100 mg):
[0022] Active substance:
[0023] Ipidacrine 3 mg
[0024] Pharmaceutically acceptable excipients:
[0025] hydroxypropyl methylcellulose 35 mg
[0026] microcrystalline cellulose 60 mg
[0027] colloidal silicon dioxide 1 mg
[0028] magnesium stearate 1 mg
[0029] Pharmaceutical Formulation 2 (Content for 1 Tablet of 250 mg):
[0030] Active substance:
[0031] Ipidacrine 40 mg
[0032] Pharmaceutically acceptable excipients:
[0033] hydroxypropyl methylcellulose 75 mg
[0034] microcrystalline cellulose 128.74 mg
[0035] colloidal silicon dioxide 3.13 mg
[0036] magnesium stearate 3.13 mg
[0037] Pharmaceutical Formulation 3 (Content for 1 Tablet of 600 mg):
[0038] Active substance:
[0039] Ipidacrine 150 mg
[0040] Pharmaceutically acceptable excipients:
[0041] hydroxypropyl methylcellulose 188 mg
[0042] microcrystalline cellulose 250 mg
[0043] colloidal silicon dioxide 6 mg
[0044] magnesium stearate 6 mg
[0045] Pharmaceutical Formulation 3 (Content for 1 Tablet of 1000 mg):
[0046] Active substance:
[0047] Ipidacrine 300 mg
[0048] Pharmaceutically acceptable excipients:
[0049] hydroxypropyl methylcellulose 280 mg
[0050] microcrystalline cellulose 400 mg
[0051] colloidal silicon dioxide 10 mg
[0052] magnesium stearate 10 mg
[0053] Pharmaceutical Formulation 4 (Content for 1 Tablet of 230 mg):
[0054] Active substance:
[0055] Ipidacrine 40 mg
[0056] Pharmaceutically acceptable excipients:
[0057] microcrystalline cellulose 140 mg
[0058] colloidal silicon dioxide 2 mg
[0059] magnesium stearate 2 mg
[0060] Pharmaceutical Formulation 6 (Content for 1 Prolonged Action Tablet of 600 mg)
[0061] Active substance:
[0062] Ipidacrine 60 mg
[0063] Pharmaceutically acceptable excipients:
[0064] microcrystalline cellulose 216 mg
[0065] colloidal silicon dioxide 2 mg
[0066] hydroxypropyl methylcellulose 120 mg
[0067] magnesium stearate 2 mg
Example 2
[0068] Evaluation of the effects of ipidacrine pharmaceutical formulation in rats with the reduced sexual activity caused by hemigonadectomy. The hemigonadectomy is similar to the pathological processes observed in the clinical picture and associated with the decrease in hormone production by the sex glands.
[0069] The model of hypogonadal state in rats induced by the hemigonadectomy corresponds to the pathological processes observed in the clinical picture and associated with the decreased hormone production of the sex glands.
[0070] The study of the ipidacrine pharmacological activity was conducted in albino male rats. The following six groups of animals were formed: 1—intact, 2—treated with sildenafil, 3—galantamine, 4—ipidacrine, 5—gonadectomized, 6—control. 30 days before the start of the main study, the experiment was performed (3 times a week for 2 weeks), namely introduction of a receptive female to the male rat. The number of ejaculations was recorded. Those animals whose level of sexual activity was characterized by stable performance of 1-2 ejaculations during the period of the test were selected.
[0071] The selected male rats underwent the hemigonadectomy (at the right) performed under ether anesthesia. Then, during 7 and 14 days prior to the course administration of the drugs, daily testing of sexual activity of the hemigonadectomized animals was carried out. The latency period and the number of mounts, intromissions and ejaculations in different groups of the animals were considered.
[0072] Administration of ipidacrine at a dose of 1.7 mg/kg once daily for 7 days to hemigonadectomized rats eliminates fluctuations in the level of the sexual activity due to external stressor effects throughout the whole course of the therapy and contributes to the increase of central motivation and ejaculatory components.
[0073] Ipidacrine in the course therapy of 2 times a day for 14 days in hemigonadectomized rats at a dose range of 0.85 to 5.1 mg/kg produces a dose-dependent increase in the sexual activity of the animals, with a maximum manifestation in 3 to 5 days at a dose of 5.1 mg/kg, and in 11 to 14 days at a dose of 0.85 to 1.7 mg/kg ( FIG. 1 ).
Example 3
[0074] Evaluation of the effects of an ipidacrine pharmaceutical formulation at reduced sexual activity in rats caused by physical stress.
[0075] The most appropriate model (in terms of the ease of implementation) is the model of psychogenic sexual dysfunction caused by exposure to physical factors (electrical current) in rats.
[0076] The pre-experiment with the animals was performed similar to that described in Example 2.
[0077] The two groups of the animals similar in the sexual activity level were formed: control (administration of distilled water), pharmaceutical formulation (on ipidacrine basis at a dose of 1.7 mg/kg). The animals of the control and experimental groups were daily exposed to current with a voltage of 30V for 30 min once a minute with an impulse with duration of 1 sec. The drug was administered 30 minutes before the stress, the testing was performed 60 min after the stress.
[0078] The administration of ipidacrine at a dose of 1.7 mg/kg once a day prior the stress contributed to a slower formation of sexual dysfunction in the rats. In an initial period (1 to 3 days), the parameters of activity were comparable to the parameters in the group nonsusceptible to the stress. Starting from the 5 th day, a significant increase in the latency period of mounts and intromissions compared to the animals nonsusceptible to stress (in the group without treatment, such changes were observed from the 1 st day of the experiment) was registered. Significant differences from the group without treatment on a number of indicators were observed on the 7 th day (latency period of intromissions) and on the 10 th day (latency period of intromissions and mounts).
[0079] When comparing the sexual activity of the stressed animals without treatment and against the background of the ipidacrine therapy at a dose of 1.7 mg/kg, the period from the 3 rd to 10 th day of the experiment was the most significant. The administration of ipidacrine provided the maintenance of the frequency of ejaculations at a level of 60-100%, while in the comparison group, this figure reduced to 20%. In the same period, a higher rate of renewal of activity after the first ejaculation was recorded in the animals of the ipidacrine group. By the end of the 14 day exposure to stress, the number of ejaculations remained at a level of 0.4-0.6 (on the 10 th and 14 th day) in the animals of the treatment group, while in the group without treatment, this parameter was not greater than 0.2 (7 th and 14 th day) ( FIG. 2 ).
Example 4
[0080] The evaluation of effects of ipidacrine pharmaceutical formulation on a model of initially hypoactive male rats with spontaneously reduced sexual function. This model is associated with the clinical conditions of anorgasmia or delayed ejaculation in humans. According to the results of the five-fold testing of the intact animals, the groups of hypoactive male rats were formed. The criterion for selection was average number of ejaculations of less than 0.5 according to the results of the five-fold testing.
[0081] To assess the effect of ipidacrine on sexual function of rats with the reduced sexual activity, the groups of the animals with initially low manifestations of copulatory and ejaculatory components of behavior were formed. This model reflects the clinical conditions of anorgasmia and delayed ejaculation. The effect of the drug on the integral indicator of the sexual function (number of ejaculations) at a dose of 0.85 to 5.1 mg/kg when administered daily is shown in FIG. 3
[0082] In hypoactive animals undergoing daily course therapy with the pharmaceutical composition (ipidacrine content of 0.85 mg/kg), an increase in the sexual activity (starting with the 2 nd week) was registered. It was manifested in the reduction of the latency period of mounts and intromissions (significant differences from the background were registered on the 7 th to 14 th day of observation). These data allow us to characterize the effect of the drug (0.85 mg/kg) on the trend level as similar changes of indicators were observed in the control group. An increase in the average number of ejaculations in the group up to 0.6-0.8 and increase of the rate of occurrence of ejaculations to 80% were noted. In some animals, the renewal of sexual activity was observed after the first ejaculation (on the average in 4-6 minutes) in contrast to the control group. While administering the pharmaceutical formulation with ipidacrine at a dose of 1.7 mg/kg (considering interspecies dose conversion), an increased central motivational component (2 to 4-fold reduction in the latency time of mounts and intromissions) after the first administration of the drug was revealed. In the subsequent periods, a slight decrease in the sexual activity (on the 3 rd or 5 th day) with an increase of indicators of sexual behavior on the 7 th , 10 th and 14 th day of the administration of the drug was observed. This was accompanied by an increase of the ejaculatory component in comparison with the control throughout the course of administration of the drug in the test dose. The number of animals able to ejaculate also increased (up to 80%).
[0083] The administration of ipidacrine at a higher dose (5.1 mg/kg) increased the sexual activity in the animals during the first 5 days of observation, which was manifested by an increase in central motivational and ejaculatory components. The latency period of mounts reduced from 33.0±5.35 to 9.3±1.93 s (p<0.05), and the latency period of intromissions from 59.8±11.34 to 10.5±1.76 (p<0.05) in 3 days of observation. Subsequent administration of the drug at this dose produced a negative effect on the manifestation of the sexual activity while in 10, 14 days of the experiment the values of indicators were comparable to the control.
[0084] Therefore, the administration of ipidacrine in the animals with the spontaneous sexual hypoactivity leads to an increase of copulatory and ejaculatory components when administered at doses of 1.7 and 5.1 mg/kg. The drug at a dose of 5.1 mg/kg is effective only when administered for 5 days. Ipidacrine at a dose of 1.7 mg/kg showed an activating effect on the sexual function throughout the whole observation period (14 days).
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Kojima J, Onodera K, Ozeki M, Nakayama M. Ipidacrine (NIK-247): A Review of Multiple Mechanisms as an Antidementia Agent CNS Drug Reviews 1998, Vol. 4, No. 3, pp. 247.259
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The invention is based on the use of ipidacrine to treat potency disorders and can be used in clinics for treating potency disorders related to the reduced production of reproductive gland hormones, disorders caused by chronic, including physical, stress, and also associated with spontaneously reduced sexual function, including anorgasmia or delayed ejaculation, and other sexual activity disorders not limiting the scope of the invention.
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BACKGROUND OF THE INVENTION
The present invention relates to a system for controlling the ignition timing of an internal combustion engine such as an automotive engine.
A learning control system for correcting the ignition timing has been proposed. The control system is adapted to advance the ignition timing so as to produce a maximum torque as long as the level of engine knocking does not exceed a tolerable level. The ignition timing stored in a RAM is corrected by a small correcting quantity (quantity of correction) and converged to a desired value little by little. The correcting quantity for the ignition timing at every updating operation is gradually reduced as the number of the learning increases, that is as the ignition timing approaches the desired value.
On the other hand, if a large disturbance occurs, such as a large change of engine load, the ignition timing must be corrected by a large quantity. However, in the state where the ignition timing approaches the desired ignition timing, the correcting quantity at each updating is very small as described above. Accordingly, it takes a long time to correct the ignition timing to a new desired timing.
SUMMARY OF THE INVENTION
The object of the present invention is to provide a control system which may quickly correct the ignition timing to a desired ignition timing when the ignition timing greatly deviates from the desired ignition timing.
According to the present invention, there is provided a system for controlling the ignition timing of an internal combustion engine having an ignition timing control device, comprising sensing means for sensing the operating conditions of the engine and for producing an engine operating condition signal, and a knock sensor for sensing engine knock and for producing a knock signal.
The system comprises first means responsive to the engine operating condition signal and knock signal for producing an ignition timing correcting signal representing an ignition timing correcting quantity which is applied to the ignition timing control device for correcting the timing, second means for detecting the change of engine operating conditions which will cause a deviation of ignition timing from a desired ignition timing and for producing a correction signal, said second means is means for detecting frequency of ignition timing correction higher than a predetermined value and third means responsive to the correction signal for increasing the ignition timing correcting quantity.
Other objects and features of this invention will become understood from the following description with reference to the accompanying drawings.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is a block diagram showing a control system according to the present invention;
FIG. 2 is a block diagram showing a main part of the control system;
FIGS. 3a and 3b show tables storing a plurality of ignition timings;
FIG. 4 shows a range of a coefficient K;
FIGS. 5, 6, 7a and 7b are flow charts showing the operation of the system; and
FIGS. 8a and 8b show a retard coefficient table and an advance determining period table, respectively.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1, an intake air pressure (or quantity) sensor 1, engine speed sensor 4 such as a crankangle sensor, and knock sensor 7 are provided to detect engine operating conditions. The output of the sensor 1 is applied to an A/D converter 3 through a buffer 2, and the output of the sensor 4 is applied to an interrupt processing circuit 6 through a buffer 5. The output of the knock sensor 7 is applied to a comparator 12 through a filter 8 and an amplifier 9, and, on the other hand, to the comparator 12 through a rectifier 10 and an amplifier 11. The comparator 12 compares both inputs and produces an output signal when an engine knock having a higher level than a predetermined value is generated. The outputs of the A/D converter 3, circuit 6 and comparator 12 are applied to a microprocessor 18 through an input port 13.
The microprocessor 18 comprises a CPU 15, RAM 16, ROM 17 and output port 14. The output of the microprocessor 18 is applied to an ignition timing control device 21 through a driver 19 so as to control the ignition timing in accordance with the engine operating conditions sensed by the sensors 1, 4 and 7.
FIG. 5 summarizes the operation of the control system. The operation is divided into a rough correction and a fine correction. At a step 30, it is decided whether a rough correction has been executed (if a rough correction completion flag RCMP is set). In accordance with the decision, the rough correction or fine correction is executed at a step 31 or 32. At a step 33, a real ignition timing SPK real is calculated.
The rough correction is an operation for obtaining a basic ignition timing SPK bs which is calculated in a basic ignition timing setting circuit 71 shown in FIG. 2. FIG. 6 shows the operation of the rough correction. At a step 37, engine speed and intake air pressure are calculated based on output signals of sensors 1 and 4. Thereafter, at a step 38, a first maximum ignition timing MAPSTD and a second maximum ignition timing MBT are read from tables 38a and 38b (FIGS. 3a, 3b) in the ROM 17, in accordance with the engine speed and intake air pressure. The first maximum ignition timing is maximum timing for producing maximum torque with low-octane gasoline without the occurrence of knocking and the second maximum ignition timing is maximum timing for producing maximum torque with high-octane gasoline without the occurrence of the knocking.
In the system, a coefficient K for correcting the ignition timing is provided. The value of the coefficient K is preliminarily set to a value between zero and 1 as shown in FIG. 4.
The coefficient K is stored in the RAM 16 and updated in accordance with engine operating conditions so as to roughly converge the ignition timing to a desired ignition timing. The updating is performed under a predetermined condition and the condition is determined at a step 39. When the difference between the first and second maximum ignition timings read from the tables 38a and 38b (FIG. 3a and FIG. 3b) is larger than a predetermined degree, for example 5°, the updating is performed. Namely, the program proceeds to a step 40, where it is determined whether a knock has occurred during the program. When the occurrence of knocking is determined, the program proceeds to a step 41, and if not, proceeds to a step 42. At step 41, the coefficient K is decremented by a correcting quantity ΔK(ΔK=K/2), and the remainder K-ΔK is stored in the RAM 16 as a new coefficient for the next updating. Accordingly, the correcting quantity ΔK at the next updating is (K-ΔK)/2. Namely, the correcting quantity is one-half of the coefficient K at updating. More particularly, if the initial coefficient is 1/2, the correcting quantity is 1/4, and if it is 0 or 1, the correcting quantity is 1/2 as seen from FIG. 4.
At the step 42, it is determined whether the engine has operated without knock occurring for a predetermined period. When knocking does not occur for the period, the coefficient K is incremented by the correcting quantity ΔK at a step 43.
After the updating of the coefficient K at step 41 or 43, it is determined whether the rough correction is completed at a step 44. As will be understood from the above description, the correcting quantity ΔK decreases as the number of the correction increases. In the system, when the correcting quantity reaches a predetermined small value, the rough correction is completed. Accordingly, if quantity ΔK reaches the predetermined value, a rough correction completion flag RCMP is set at a step 45, or if not, the flag is reset at a step 46. On the other hand, the total correcting quantity SPK prt and the number of correction NUM of the ignition timing are stored in an ignition timing correcting quantity table 73 and a table 74 (FIG. 2) for the number of the correction. At a step 47, a basic ignition timing SPK bs is calculated from the following formula
SPK.sub.bs =MAPSTD+K×ΔMAPMBT (1)
where ΔMAPMBT=MBT-MAPSTD
The basic ignition timing is applied to an engine 72 (FIG. 2) to operate the engine at the ignition timing. The coefficient K is stored in the RAM 16. If the rough correction is not completed, the coefficient K is updated at the next program so as to roughly converge the ignition timing to a desired ignition timing as described above. It will be understood that if the initial coefficient K is 0, the basic ignition timing SPK bs calculated by the formula (1) is the maximum ignition timing MAPSTD at the first program. The basic ignition timing SPK bs obtained by the rough correction is further corrected by the fine correcting operation as described hereinafter.
Referring to FIGS. 7a and 7b, at a step 52, it is decided whether the engine operation is in a range which is proper to correct the basic ignition timing SPK bs . If it is in the range, the correcting quantity SPK prt and the number of correction NUM are read from tables 73 and 74 at a step 53. Then, at a step 54, a retard coefficient LN for retarding quantity RET is looked up from a retard coefficient table 75 (FIG. 2) of FIG. 8a in accordance with the number of correction NUM, and an advance determining period ADJ is looked up from an advance determining period table 76 (FIG. 2) of FIG. 8b in accordance with the number of correction NUM. Thereafter, the program proceeds to a step 55, where it is decided whether a knock has occurred during the program. When the occurrence of knocking is determined, the program proceeds to a step 56, and if not, it proceeds to a step 59. At step 56, the intensity of the knock and the interval of knocks are calculated at a calculating circuit 78 (FIG. 2), and then, retarding quantity KNK is looked up from a retarding quantity table 79 in accordance with the intensity and the interval of the knocking. At a step 57, a real retarding quantity RET real is calculated by multiplying the retarding quantity KNK and retard coefficient LN together (RET real =KNK×LN). Thereafter, the program proceeds to a step 58, where the correcting quantity SPK prt stored in the table 73 is subtracted with the real retarding quantity RET real to obtain a new correcting quantity SPK prtr which is stored in the table 73.
On the other hand, at the step 59, it is decided whether a knock occurred in the advance determining period ADJ, which is performed at a comparator 80 in FIG. 2. When knocking does not occur in the period, the program proceeds to a step 60, where an advancing quantity ADV of a constant small value is added to the correcting quantity SPK prt to obtain a new correcting quantity SPK prta which is performed in an advancing quantity setting circuit 81 in FIG. 2 and stored in the table 73. Thereafter, a step 61, it is determined whether the new correcting quantity SPK prta is larger than a limit value which is obtained by subtracting the basic ignition timing SPK bs from the maximum ignition timing MBT (MBT-SPK bs ). When the new correcting quantity SPK prta is smaller than the limit value, the new correcting quantity is stored in the table 73 at a step 63. If it is larger than the limit value, value of MBT-SPK bs is used as a new correcting quantity (at a step 62) and stored in the table 73.
Thereafter the program proceeds to a step 64, where it is decided whether knock larger than a predetermined intensity has occurred or the frequency of correction in the same direction (advance or retard) is higher than a predetermined value, which is caused by large disturbance. When such a phenomenon occurs, the program proceeds to a step 65 (circuit 82), where the number of correction NUM which is applied to the tables 75 and 76 (FIGS. 8a and 8b) is reduced. Accordingly, the retard coefficient LN to be obtained in the next program is increased, and the advance determining period ADJ is reduced as seen from FIGS. 8a and 8b, which means that the new correcting quantity SPK prtr or SPK prta increases. Thus, the ignition timing is largely corrected at succeeding programs, so that the timing can quickly converge to a desired value.
While the presently preferred embodiment of the present invention has been shown and described, it is to be understood that this disclosure is for the purpose of illustration and that various changes and modifications may be made without departing from the scope of the invention as set forth in the appended claims.
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A system for quickly converging the ignition timing to a desired timing when a large deviation occurred in the ignition timing. Change of engine operating conditions which will cause such a deviation is detected by a large engine knock to produce a correction signal. In response to the correction signal, an ignition timing correcting quantity is increased so as to quickly correct the ignition timing.
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FIELD OF THE INVENTION
The present invention mainly relates to the aldehyde derivative of Substituted oxazolidinones and more particularly to a prodrug of 5-chloro-N-({(5S)-2-oxo-3-[4-(3-oxomorpholin-4-yl)phenyl]-1,3-oxazolidin-5-yl}methyl)thiophene-2-carboxamide, and the process for preparation of prodrug. The prodrug of formula (B); is chemically designated as 5-chloro-N-formyl-N-({(5S)-2-oxo-3-[4-(3-oxomorpholin-4-yl)phenyl]-1,3-oxazolidin-5 yl}methyl)thiophene-2-carboxamide, or pharmaceutically accepted salt or solvate form or hydrate form. Further this invention relates to the use of prodrug in treatment of prophylaxis of diseases, pulmonary embolism, and deep venous thrombosis more particularly to thromboembolic disorder.
BACKGROUND OF THE INVENTION
A large number of medicaments are administered as prodrugs which exhibits an improved bioavailability by comparison with the underlying active ingredient, for example, by improving the physicochemical profile, specifically the solubility, the active or passive absorption properties or the tissue-specific distribution. In order to achieve an optimal profile of effects it is necessary for the design of the prodrug residue as well as the desired mechanism of liberation to conform very accurately to the individual active ingredient, the indication, the site of action and the administration route
The importance of the prodrug is more, when the main moiety raises concerns of solubility, stability and oral bioavailability.
Rivaroxaban is an orally active direct factor Xa (FXa) inhibitor drug, used for the prevention and treatment of various thromboembolic diseases, in particular pulmonary embolism, deep venous thrombosis, myocardial infarction, angina pectoris, reocclusion and restenosis after angioplasty or aortocoronary bypass, cerebral stroke, transitory ischemic attacks, and peripheral arterial occlusive diseases.
Rivaroxaban i.e. 5-chloro-N-({(5S)-2-oxo-3-[4-(3-oxomorpholin-4-yl)phenyl]-1,3-oxazolidin-5-yl}methyl)thiophene-2-carboxamide, has a CAS number of 366789-02-8, a molecular formula of C 19 H 18 ClN 3 O 5 S, and the following structure:
Rivaroxaban, though effective for prevention and treatment of various thromboembolic diseases, often raises issue of dosage and relative bio availability.
WO 01/47919, application disclosed the Rivaroxaban with applications for prevention and treatment of various thromboembolic diseases. Further this patent describes a method for preparation of Rivaroxaban of formula (I), wherein 4-(4-aminophenyl)morpholin-3-one is reacted with 2-[(2S)-oxiran-2-ylmethyl]-1H-isoindole-1,3(2H)-dione, in presence of solvent to obtain 2-[(2R)-2-hydroxy-3-{[4(3-oxomorpholin-4-yl)phenyl]amino}propyl]-1H-isoindole-1,3(2H)-dione which is further converted to 2-({(5S)-2-oxo-3-[4-(3-oxomorpholin-4-yl)phenyl]-1,3-oxazolidin-5-yl}methyl)-1H-isoindole-1,3(2H)-dione by phosgene equivalent. Departing of the pthalamide group affords 4-{4-[(5S)-5-(aminomethyl)-2-oxo-1,3-oxazolidin-3-yl]phenyl}morpholin-3-one, which is finally coupled with 5-chlorothiophene-2-carbonyl chloride to give 5-chloro-N-({(5S)-2-oxo-3-[4-(3-oxomorpholin-4-yl)phenyl]-1,3-oxazolidin-5-yl}methyl)thiophene-2-carboxamide i.e. Rivaroxaban of formula (I) as shown in scheme-1;
The disclosed process, involves lengthy reaction periods, excess mole ratios of reactants and reagents, use of unsafe solvents such as methanol and methylene dichloride. Moreover title compound is isolated by column chromatography which is not feasible on commercial scale.
U.S. Pat. No. 7,932,278 B2, discloses the preparation of the compound Rivaroxaban by the synthesis scheme below:
The compounds according to the invention are suitable for use as medicaments for the treatment and/or prophylaxis of diseases in humans and animals.
WO 2009/023233 discloses the compounds that are substituted oxazolidinones derivatives and pharmaceutically acceptable salts thereof. More specifically, this invention relates to novel oxazolidinones compounds that are derivatives of rivaroxaban. The invention also provides pyrogen-free compositions comprising one or more compounds of the invention and a carrier, and the use of the disclosed compounds and compositions in methods of treating diseases and condition that are beneficially treated by administering a selective inhibitor of factor Xa, such as rivaroxaban.
The present invention relates to a prodrug of Rivaroxaban. The compounds according to our instant invention are selective inhibitors of blood coagulation factor Xa which act in particular as anticoagulants, with favorable physicochemical properties, advantageous in therapeutic application such as treatment of thromboembolic disorders; inhibitor of factor Xa, and/or thromboembolic complications.
SUMMARY
In its main aspect, the present invention discloses a compound of formula (B), chemically designated as 5-chloro-N-formyl-N-({(5S)-2-oxo-3-[4-(3-oxomorpholin-4-yl)phenyl]-1,3-oxazolidin-5-yl}methyl)thiophene-2-carboxamide.
In another aspect, of the present invention discloses the use of the compounds of formula (B), for treatment and/or prophylaxis of disorders, such as thromboembolic disorders; inhibitor of factor Xa, and/or thromboembolic complications. The “thromboembolic disorders” include in the context of the present invention disorders such as myocardial infarction with ST segment elevation (STEMI) and without ST segment elevation (non-STEMI), stable angina pectoris, unstable angina pectoris, reocclusions and resteneses following coronary interventions such as angioplasty or aortocoronary bypass, peripheral arterial occlusive diseases, pulmonary embolisms, deep venous thromboses and renal vein thromboses, transient ischaemic attacks, and thrombotic and thromboembolic stroke.
In yet another aspect, the present invention discloses a use of the compound formula (B) for prevention and treatment of cardiogenic thromboembolisms, such as, for example, cerebral ischaemias, stroke and systemic thromoboembolisms and ischaemias, in patients with acute, intermittent or persistent cardiac arrhythmias such as, for example, atrial fibrillation, and those undergoing cardioversion, also in patients with heart valve diseases or with artificial heart valves. The compound according to the invention is additionally suitable for the treatment of disseminated intravascular coagulation (DIC).
Another aspect of the present invention is to provide the process for the preparation of the compound formula (B) which is substantially free from impurities.
Yet another aspect of the present invention is to provide compound formula (B) in crystalline or amorphous form.
Yet another aspect, the present invention discloses a compound formula (B) in a pharmaceutically accepted salt or hydrate form or solvate form of compound formula (B).
DETAILED DESCRIPTION OF THE INVENTION
In its main embodiment, the present invention comprises the compound formula (B), chemically designated as 5-chloro-N-formyl-N-({(5S)-2-oxo-3-[4-(3-oxomorpholin-4-yl)phenyl]-1,3-oxazolidin-5-yl}methyl)thiophene-2-carboxamide, having the structure:
Or its pharmaceutically accepted salt or solvate form or hydrate form, which acts as a prodrug of for compound formula (I) chemically designated as 5-chloro-N-({(5S)-2-oxo-3-[4-(3-oxomorpholin-4-yl)phenyl]-1,3-oxazolidin-5-yl}methyl)thiophene-2-carboxamide, having the structure:
The word prodrug includes the compound which may be pharmacologically active or inactive, but on ingestion is enzymatically or hydrolytically converted by the body in to the active compound. The present invention focuses on these concerns The compound of formula (B), as disclosed in vitro and in vivo animal studies has shown superior solubility and stability as is explicitly reflected in the examples, and hence encourage clinical trials.
The present compound formula (B), exists in stereoisomeric forms (enantiomers, diastereomers). Accordingly, the invention comprises the enantiomers or diastereomers and their respective mixtures. From such mixtures of enantiomers and/or diastereomers, it is possible to isolate the stereoisomerically uniform components in a known manner. If the compounds according to the invention can be present in tautomeric forms, the present invention comprises all tautomeric forms.
The present invention carried out the detailed study on the solubility, stability and liberation behavior of the invented compound (compound formula B). Further INVITRO and INVIVO studies for compound formula (B) are carried out in order to established the selective activity such as In Vitro Liver Microsomal Stability Assay, In Vitro Stability in Rat, Mouse and Human Plasma, CYP Inhibition Assay, Plasma Protein Binding Intravenous and Oral Pharmacokinetics in Wistar Rats, Suspension for Intravenous Administration and Solution for Oral Administration, anticoagulant activity and Antithrombotic activity, wherein theses study are well exemplified or illustrated with best mode in examples section/example (B).
In an important embodiment, the present invention provides for a process for the preparation of compound formula (B) comprising of:
a) reacting, 4-(4-aminophenyl)morpholine-3-one of formula (II) with 2-[(2S)-oxiran-2-ylmethyl]-1H-isoindole-1,3(2H)-dione of formula (III) in a suitable solvent to obtain 2-[(2R)-2-hydroxy-3-{[4-(3-oxomorpholin-4-yl)phenyl]amino}propyl]-1H-isoindole-1,3(2H)-dione of formula (IV);
b) preparing compound of formula (VI) by reacting compound of formula (IV) with di-1H-imidazol-1-ylmethanone of formula (V);
In the alternative, in a suitable solvent compound of formula IV is converted to a compound of formula VI in the presence of a base.
c) eliminating the pthalamide group from compound of formula (VI) by using a suitable de-protecting agent and acid in a suitable solvent in order to get the acid addition salt of 4-{4-[(5S)-5-(aminomethyl)-2-oxo-1,3-oxazolidin-3-yl]phenyl}morpholin-3-one formula (VII).
Where A is an acid addition salt; In the alternative, compound of formula VII can also be isolated as a free base; The synthesis of compound of Formula VII either as an acid addition salt or a free base is known and hence not claimed. Compound of Formula VII may be made by any known method.
d) The compound of formula (VII) with acid addition salt is reacted in the presence of a base with an acid to obtain a novel intermediate formula (A), N-({(5S)-2-oxo-3-[4-(3-oxomorpholin-4-yl)phenyl]-1,3-oxazolidin-5-yl}methyl)formamide;
In the alternative where compound of Formula VII is a free base it is directly reacted with an acid to give a novel intermediate formula (A), N-({(5S)-2-oxo-3-[4-(3-oxomorpholin-4-yl)phenyl]-1,3-oxazolidin-5-yl}methyl)formamide;
e) reacting compound formula (A) with compound formula (VIII) or 5-chlorothiophene-2-carbonitrile in suitable solvent and base in order to obtain the compound formula (B), optionally in the presence of catalyst and/or activating agents;
Wherein;
Y may be sulfonyloxy, imidazole, triazole, tetrazole, alkoxy, substituted alkoxy, tri-halomethoxy, N-hydroxysuccinamide, hydroxy, esters, primary amine, secondary amine p-nitrophenol, N-hydroxythalamide, N-hydroxybenzotriazole, chlorine, fluorine, bromine & iodine. Base used may be inorganic or organic.
Compound of Formula B, is prodrug of compound of Formula I which is popularly known as rivaroxaban having the structure of formula-I.
When the aldehyde group of compound of formula B, is eliminated on exposure to an acidic or basic environment, it is converted to the active moiety, Rivaraxoban, Hence Compound formula (B) when treated with acid or base in suitable solvent departs the aldehyde group from compound formula (B), to obtain the title compound Rivaroxaban formula (I);
The instant invention further extend to the preparation of acid addition salt of compound formula (VII), in order to get the purified compound without any further purification by acid-base treatment, or solvent crystallization.
The solvent used in step (a) and step (c) may be same or different; wherein the said solvent is an organic solvent selected from the group comprising aliphatic hydrocarbons, aromatic hydrocarbons, dialkylformamides, ethers, cyclic ethers, substituted cyclic ethers, alcohol, ketones, dialkylsulfoxides, dialkylacetamides, nitriles, ionic liquids, halogenated aliphatic hydrocarbons and water or mixtures thereof but more preferable solvent which is neutral towards the reactants.
The step (a) could be carried out at temperature in the range of 0° C. to 95° C. Usually the reaction may be carried out at temperature up to reflux temperature of the said solvent.
The solvent used in step (b) for the preparation of compound of formula (VI) is an organic solvent selected from the group comprising of aliphatic hydrocarbons, aromatic hydrocarbons, dialkylformamides, ethers, cyclic ethers, substituted cyclic ethers, ketones, dialkylsulfoxides, dialkylacetamides, nitriles, ionic liquids, halogenated aliphatic hydrocarbons or mixtures thereof.
The solvent used in step (c) is an organic solvent selected from the group comprising aliphatic hydrocarbons, aromatic hydrocarbons, dialkylformamides, ethers, cyclic ethers, substituted cyclic ethers, dialkylsulfoxides, dialkylacetamides, nitriles, ionic liquids, halogenated aliphatic hydrocarbons and water or mixtures thereof. Further the compound formula (VII) may be prepared in terms of acid addition salt by using inorganic or organic acid.
In step (d) the compound of formula (VII) may be used in free base form or its acid addition salt. The solvent used in the step (d) is an organic solvent, may be mixture or water and organic solvent. Formylating agent used in the step (d) may be formic acid, alkyl formate etc. The solvent used in the reaction may be selected for the aromatic hydrocarbons, nitriles, aliphatic hydrocarbons, ethers preferably aromatic hydrocarbon more preferably toluene and xylene. The base used in step (d) is selected from organic or inorganic base.
In step (e) compound formula (A) was treated with formula (VIII) optionally in the presence of base which may be inorganic or organic in solvent selected from the group comprising aliphatic hydrocarbons, aromatic hydrocarbons, dialkylformamides, ethers, cyclic ethers, substituted cyclic ethers, dialkylsulfoxides, dialkylacetamides, nitriles, ionic liquids, esters, halogenated aliphatic hydrocarbons, ketones, cyclic amides and water or mixtures thereof to obtain Rivaroxaban precursor of formula (B). Activating agents used in the reaction of step (e) comprises CDI, DCC, HOBt, DMAP, EDCI, boric acid, boronic acid, phenyl boronic acid etc. and mixture thereof.
According to yet another embodiment, the present invention provides a process for preparation of formula (B);
Comprises:
reacting compound formula A)
with compound of formula (VIII) to obtain compound formula (B)
Wherein;
Formula (VIII)
Y may be sulfonyloxy, imidazole, triazole, tetrazole, alkoxy, substituted alkoxy, tri-halomethoxy, N-hydroxysuccinamide, hydroxy, esters, primary amine, secondary amine p-nitrophenol, N-hydroxythalamide, N-hydroxybenzotriazole, chlorine, fluorine, bromine& iodine. Base used may be inorganic or organic.
The solvent used for the said reaction may be inorganic or organic in solvent selected from the group comprising aliphatic hydrocarbons, aromatic hydrocarbons, dialkylformamides, ethers, cyclic ethers, substituted cyclic ethers, dialkylsulfoxides, dialkylacetamides, nitriles, ionic liquids, esters, halogenated aliphatic hydrocarbons, ketones, cyclic amides and water or mixtures thereof to obtain Rivaroxaban precursor of formula (B) Activating agents used in the reaction comprises CDI, DCC, HOBt, DMAP, EDCI, boric acid, boronic acid, phenyl boronic acid etc. and mixture thereof. The base used is selected from organic or inorganic base and optionally compound formula (B) may be purified or can be used as such for next reaction.
According to yet another embodiment of the present invention, recemate of free base or acid addition salt compound of formula (VII) may be done using enzymatic kinetic resolution.
Wherein;
A is acid addition salt; acid may be inorganic or organic acid;
In yet another embodiment of the present invention, the base used in aforementioned step is inorganic or organic and solvent is selected from the group comprising aliphatic hydrocarbons, aromatic hydrocarbons, dialkylformamides, ethers, cyclic ethers, substituted cyclic ethers, dialkylsulfoxides, dialkylacetamides, nitriles, ionic liquids, esters, halogenated aliphatic hydrocarbons, ketones, cyclic amides and water or mixtures thereof to obtain Rivaroxaban of formula (I) Activating agents used in the reaction comprises CDI, DCC, HOBt, DMAP, EDCI, boric acid, boronic acid, phenyl boronic acid etc. and mixture thereof.
As used herein, the term “hydrate” means a compound which further includes a stoichiometric or non-stoichiometric amount of water bound by non-covalent intermolecular forces. As used herein, the term “solvate” means a compound which further includes a stoichiometric or non-stoichiometric amount of solvent such as water, acetone, ethanol, methanol, dichloromethane, 2-propanol, or the like, bound by non-covalent intermolecular forces.
The present invention is described in the examples given below; further these are provided only to illustrate the invention and therefore should not be construed to limit the scope of the invention.
Example—A
Abbreviations and Acronyms
LC-MS—Coupled Liquid chromatography-mass spectroscopy
HPLC—High performance liquid chromatography
LLQQ—Lower limit of quantification
SD—Standard deviation
AUC—Area under curve
DMSO—dimethyl sulphoxide
NADPH—nicotinamide adenine dinucleotide phosphate-oxida
CYP—cytochrome
BLOQ—below limit of quantification
SIF—Stimulated Intestinal fluid
SGF—Stimulated gastric fluid
CV—Concentration value
C max Highest concentration
The following exemplary embodiment in terms of details study illustrates the invention but it is not restricted to these examples with procedure.
Example—1
Preparation of N-({(5S)-2-oxo-3-[4-(3-oxomorpholin-4-yl)phenyl]-1,3-oxazolidin-5-yl}methyl)formamide (Aldehyde of Primary Amine)
In a four neck round bottom flask charged with 4-{4-[(5S)-5-(aminomethyl)-2-oxo-1,3-oxazolidin-3-yl]phenyl}morpholin-3-one free base (50 g) toluene (350 ml) and formic acid (21.63 g). Reaction mass then heated azeotropically to 110-120° C. employing dean-stark apparatus for 3 to 4 h. (water removed azeotropically) Reaction mass is cooled to 25 to 30° C. Obtained solid is filtered off and washed by toluene.
Yield 96%
Example—2
Preparation of 5-chloro-N-formyl-N-({(5S)-2-oxo-3-[4-(3-oxomorpholin-4-yl)phenyl]-1,3-oxazolidin-5-yl}methyl)thiophene-2-carboxamide (Compound Formula-B)
Added N-({(5S)-2-oxo-3-[4-(3-oxomorpholin-4-yl)phenyl]-1,3-oxazolidin-5-yl}methyl)formamide (1 g), dichloromethane (25 ml) in a clean dry 4 neck R.B. flask at 25 to 30° C. To this clear solution added potassium carbonate (0.89 g) and stirred at 25 to 30° C. for 30 minutes. To this reaction mass, slowly added solution of 5-chlorothiophene-2-carbonyl chloride (1.0 g), and dichloromethane (5 ml). The obtained reaction mass then stirred at 25 to 30° C. for 5 to 6 h. Added water (25 ml) to reaction mass and separated organic layer. Obtained organic 4 layer was then washed by water (25 ml×2). Finally organic layer is dried over sodium sulfate and concentrated under reduced pressure to obtain residue. Added methanol (5 ml) to the residue and heated to reflux to get a clear solution. The obtained clear solution was gradually cooled to 15 to 20° C. The precipitated solid then filtered off and washed by chilled methanol (1 ml).
1 H-NMR (400 Mz, d 6 -DMSO), δ=3.74-3.77 (m, 2H), 3.84-3.87 (m, 1H), 4.02-4.05 (m, 2H), 4.07-4.11 (n, 2H), 4.12-4.15 (m, 1H), 4.34-4.41 (m, 3H), 4.94-5.00 (m, 1H), 7.00-7.01 (d, 1H thiophene), 7.30-7.31 (d, 1H thiophene), 7.33-7.37 (dt, 2H aromatic), 7.55-7.58 (dt, 2H aromatic), 9.28 (s, 1H aldehyde)
The example 2 is carried out in different solvents such as acetone, toluene and ether the with the same molar ratio/parts wherein the varies in yield noted below;
Solvent(s)
yield
Acetone
75% (reaction perform as reflect in example 02)
Toluene
78% (reaction perform as reflect in example 02)
Ether
79% (reaction perform as reflect in example 02)
Example—3
Preparation of 5-chloro-N-({(5S)-2-oxo-3-[4-(3-oxomorpholin-4-yl)phenyl]-1,3-oxazolidin-5-yl}methyl)thiophene-2-carboxamide (Nitrile Route)
To a solution of 4-{4-[(5S)-5-(aminomethyl)-2-oxo-1,3-oxazolidin-3-yl]phenyl}morpholin-3-one hydrochloride (5.7 g) in ethanol (70 ml) added potassium carbonate (7.1 g) and the mixture was stirred 2 h at 25 to 30° C. then filtered to obtain 4-{4-[(5S)-5-(aminomethyl)-2-oxo-1,3-oxazolidin-3-yl]phenyl}morpholin-3-one (free base). In another flask charged solution of 5-chlorothiophene-2-carbonitrile (2.9 g) under nitrogen in ethanolic HCl (12 ml) and stirred for 5 h at room temperature till white precipitate was obtained. Distilled under nitrogen to avoid from moisture and obtained residue added in solution of 4-{4-[(5S)-5-(aminomethyl)-2-oxo-1,3-oxazolidin-3-yl]phenyl}morpholin-3-one. The mixture was stirred for 16 to 18 h at reflux temperature. Aq. ethanol (5 ml) was and mixture heated at reflux temperature for 10 to 12 h to obtain 5-chloro-N-({(5S)-2-oxo-3-[4-(3-oxomorpholin-4-yl)phenyl]-1,3-oxazolidin-5-yl}methyl)thiophene-2-carboxamide (crud material) which is further purified by column Chromatography.
Example—4
Preparation of N-({(5S)-2-oxo-3-[4-(3-oxomorpholin-4-yl)phenyl]-1,3-oxazolidin-5-yl}methyl)formamide
A four neck round bottom flask was charged with 4-{4-[(5S)-5-(aminomethyl)-2-oxo-1,3-oxazolidin-3-yl]phenyl}morpholin-3-one Hydrochloride (250 g), Dichloromethane (1250 ml) and ammonia (250 ml). The solution stirred for 15 min and the layers separated, Added toluene (1250 ml) to the organic layer, along with water (500 ml) and formic acid (140.6 g). Reaction mass was then heated azeotropically to 110-120° C. employing dean-stark apparatus for 3 to 4 h. (water removed azeotropically) Reaction mass was cooled to 25 to 30° C. Obtained solid then filtered off and washed by toluene.
Yield=80.0%
Example—5
Preparation of 5-chloro-N-formyl-N-({(5S)-2-oxo-3-[4-(3-oxomorpholin-4-yl)phenyl]-1,3-oxazolidin-5-yl}methyl)thiophene-2-carboxamide
Added N-({(5S)-2-oxo-3-[4-(3-oxomorpholin-4-yl)phenyl]-1,3-oxazolidin-5-yl}methyl)formamide (120 g), dichloromethane (2400 ml) to a clean dry 4 neck R.B. flask at 25 to 30° C. cooled the reaction mass to 0 to 5° C. To this solution added Diisopropylethyl amine (145.7 g) dropwise manner, a solution of 5-chlorothiophene-2-carbonyl chloride (170 g), and dichloromethane (240 ml) at 0 to 5° C. The obtained reaction mass was then stirred at 25 to 30° C. and heated to reflux for 12 hr. The reaction mass was cooled to 25 to 30° C. washed with 10% citric acid solution (2×360 ml), and separated organic layer. Obtained organic layer then washed by water (600 ml×2) and concentrated under reduced pressure to obtain a residue. Added methanol (600 ml) to residue and stirred for 20 min. The precipitated solid was then filtered off, washed by methanol (240 ml), sucked dry and the wet cake taken into a flask methanol (600 ml) added and the solution was then stirred for 30 min., solid then filtered off and washed by methanol (240 ml).
Yield=85.0%
Example—B
Determination of the Stability of the Compound Formula B in SGF and SIF Fluids
The compound formula (B), is dissolved in DMSO and then diluted with methanol:water (90:10. Stability in Buffer at Various pH buffers and SIF/SGF medium are studied:
5.7 mg of the compound formula (B), is weighed into a 2 ml HPLC vial and dissolved in 0.250 ml DMSO. 2 μl of the compound formula (B) solution is added to 250 μl of the respective buffer solution and kept at room temperature on incubator shaker for 24 hr. On completion of incubation period, the solution is centrifuged and supernatant is taken. To the supernatant, ice cold acetonitrile containing IS is added, vortexed and injected into LCMS/MS.
LC/MS/MS Method:
API 4000, ESI Agilent 1100 column: Gemini Nx 100 mm×4.6 mm 5.μ; column temperature: 30° C.; eluent A: 0.1% formic acid in water, eluent B: acetonitrile; gradient: 0-2.5 min 95% A, 5% B; 2.5-2.6 min 5% A, 95% B; 2.6-4.2 min 95% A, 5% B; flow rate: 0.8 ml/min; ESI. Q1:464.098, Q3:144.255
Decomposition of the exemplary compound in these solutions was observed at pH 7.4 and pH 7.8.
(Buffer) Solutions Employed:
Prepared 0.1 mol of citric acid and 0.2 mol of di sodium hydrogen phosphate in water. Buffer pH 2.2, 4 and 7.8 are prepared using citric acid and disodium hydrogen phosphate by adjusting the pH with 0.1N HCl or 1N NaOHpH 7.4: 8.89 g disodium hydrogen phosphate (Solution A) add to 1 liter of water, 1.5601 g sodium di-hydrogen phosphate (solution B) are made up to 1 liter with water; Solution A (19 ml) and Solution B (81 ml) are mixed. SIF/SGF: 2.38 g of SIF original powder (biorelavant media) is dissolved in 1 L of milliQ water. The pH of the solution is adjusted for SIF (7.4) and SGF (2.2) with 0.1N HCl. The ratios of the peak areas (F) at the respective time points in relation to the peak areas at the starting time are calculated
In this simulating SIF and SGF study samples, the simulating fluid stability of the compound formula B was evaluated to see the extent the compound remaining in tact at various time points at intestinal and gastric pH condition in comparison against zero minute. The peak area (F) is directly correlated to the amount of test compound which is quantified by the LC MS method.
In simulating intestinal and gastric fluid, the area of the formula B compared with zero minute area to 120 min. The compound area remained the same over 120 min showing stability at intestinal conditions and the similar results were observed at simulating gastric conditions.
In buffer stability at pH 2.2 and 7.4
In this buffer stability of varying pH conditions of pH 2.2, 4 and 7.8, the stability of the compound formula B at various pH conditions was evaluated to see the extent of the compound remaining in tact at specified time points in comparison against zero minute/or single point calibration neat aqueous standard. In these pH conditions of pH 7.4, pH 2.2, there is formation of rivaroxaban which is monitored by LCMS. There is presence of formula B seen which is at pH 2.2 and 4.0 although there is a degradation and conversion to rivaroxaban in these pH conditions.
Interestingly, there is conversion of rivaroxaban which was monitored by LCMS. This proves that the formula B compound is degraded in varying pH buffer conditions and rivaroxaban formation is observed. In buffers of pH there is a conversion to rivaroxaban in in-vitro conditions which is also observed to be translating in the in-vivo conditions supported by evidence in in-vivo rat pharmacokinetic studies in rats. Also there is evidence that conversion to rivaroxaban is found in various in-vitro assays like metabolic stability studies with microsomes and plasma stability studies in mouse, rat and humans.
In this assay, a formation of the rivaroxaban was found, as well as test substance (compound formula B) at various pH conditions. However, the test compound formula B is stable at simulating intestinal conditions. By plotting the comparison of stability of formula B at various pH conditions are well illustrated in Table 1, 2 & 3.
Table 1 represents the stability comparison chart of compound formula B at pH 7.8, pH 4 and pH 2.1.
Analyte Peak Sample Name Area (counts) Average SD CV Compound pH 2.1 20975674 28315038 162.0453269 0.000572294 formula B 35654402 PH 4 42841292 34879190 285.7428233 0.000819236 26917087 pH 7.8 35312 38907.5 0.097829461 0.000251441 42503 Standard 40131132 39849828 11.6442782 2.92204E−05 39542018 39876334
Table 2 represents the stability comparison chart of compound formula B at simulating intestinal fluid.
Analyte IS Stability Sample Peak Area Peak Area Area in SIF Name (counts) (counts) Ratio Average SD CV Compound Zero min 38191589 165067 231.371 226.928 6.2833509 2.7688742 formula B 39972052 179662 222.485 30 min 37765238 188499 200.347 194.377 8.442855 4.3435463 36339204 192876 188.407 60 min 35757521 194543 183.803 182.7045 1.5535136 0.8502875 36426366 200580 181.606 120 min 34245401 200460 170.834 179.8485 12.748428 7.0884262 33738135 178638 188.863
Table 3 represents the stability comparison chart of compound formula B at simulating gastric fluid.
Analyte IS Stability Sample Peak Area Peak Area Area % Parent in SGF Name (counts) (counts) Ratio Average SD CV remaining Conclusion Compound Zero min 34733277 186737 186.001 202.267 23.003598 11.372887 100 Compound Formula B 32540774 148905 218.533 Formula B 30 min 32217743 147631 218.232 200.7875 24.670248 12.286745 99.27 is stable 36940283 201482 183.343 60 min 35234526 174138 202.336 204.6365 3.2533983 1.5898426 101.17 35427185 171198 206.937 120 min 36170541 185892 194.578 202.3615 11.007531 5.4395383 100.05 31588036 150315 210.145
2. In Vitro Stability in Rat, Mouse and Human Plasma (LC-MS Detection)
1 mg of the compound formula (B) is weighed into a 1.5 microfuge tube and dissolved in DMSO. The final concentration of the test compound in the assay is 5 micromolar. The compound formula (B) was added to Rat or human plasma or mouse plasma, incubated at 37.degree. C. The 100 microliters of aliquot at time point was removed and and diluted with ice cold acetonitrile containing IS (200.mu·L) to stop the reactions. Samples are centrifuged at 10,000 RPM for 5 minutes to precipitate proteins. Supernatants are transferred to micro centrifuge tubes and stored at −20° C. for analysis of LC/MS/MS. The percent parent remaining of the test substance is calculated as ratio of peak area at each time point to peak area ratio at zero min, multiplied by 100. The compound formula (B) is observed to be converted in to Rivaroxaban.
LC/MS/MS Method:
API 4000, ESI Agilent 1100 column: Gemini Nx 100 mm×4.6 mm 5.1; column temperature: 30° C.; eluent A: 0.1% formic acid in water, eluent B: acetonitrile; gradient: 0-2.5 min 95% A, 5% B; 2.5-2.6 min 5% A, 95% B; 2.6-4.2 min 95% A, 5% B; flow rate: 0.8 ml/min; ESI. Q1:464.098, Q3:144.255
Table-4;
Represent the Plasma stability in Human, Rat and Mouse of the test compound (formula-B) and rivaroxaban
TABLE 4
Plasma stability in Human, Rat and Mouse of the test compound (formula-B) and rivaroxaban
% Parent remaining (Human)
% Parent remaining(rat)
Test Product
Test Product
Test Product
Test Product
(Compound
Rivaroxaban
(Compound
Rivaroxaban
Time(min)
formula-B)
formation*
Rivaroxaban
formula-B)
formation
Rivaroxaban
0
100
100
100
100
30
95.46
100
100
82.35
60
77.84
99.68
82.43
88.4
Conversion
Conversion to
Rivaroxaban
99.99%,
Conversion to
Rivaroxaban
88.4%,
rivaroxaban is
formation in
unchanged,
rivaroxaban is
formation in
unchanged,
seen from zero
Test substance
stable in
seen from zero
Test substance
stable in
min. Neglible
plasma
min. Neglible
plasma
amount of test
amount of test
product detected
product detected
% Parent remaining(Mouse)
Test Product
Test Product
(Compound
Time(min)
formula-B)
Rivaroxaban
Rivaroxaban
0
100
100
30
100
100
60
82.18
100
Conversion
Conversion to
Rivaroxaban
unchanged,
rivaroxaban is
formation in
stable in
seen from zero
Test substance
plasma
min. Neglible
amount of test
product detected
Table 4 shows the stability assay of the compound of formula B, in plasma matrix of rat, mouse and human. The experiment was conducted to determine the stability of the compound of formula B, as well as to see whether the conversion of the formula B compound to rivaroxaban occurs in plasma matrix of mouse, rat and human. Rapid conversion to rivaroxaban was observed in experiments conducted with all three species. Negligible amount of the compound of formula B was observed in in-vitro plasma stability experiment and rapid conversion to rivaroxaban observed in in-vitro conditions using plasma samples from the tested species
CYP Inhibition Assay
The ability of substances to inhibit CYP1A2, CYP2C9, CYP2D6, CYP2C19, CYP2J2 and CYP3A4 in humans was investigated with pooled human liver microsomes as enzyme source in the presence of standard substrates (see below) which form CYP-isoform-specific metabolites. The inhibitory effects are investigated with eight different concentrations of the test compounds (0.001, 0.01, 0.1, 0.3, 1, 3, 10 μM), compared with the extent of the CYP-isoform-specific metabolite formation of the standard substrates in the absence of the compound formula (B), and the corresponding IC.sub.50 values are calculated. A standard inhibitor which specifically inhibits a single CYP isoform serves as control of the results obtained.
Procedure:
Incubation of phenacetin, diclofenac, dextromethorphan, mephenotoin, albendazole and testosterone with human liver microsomes in the presence of in each case eight different concentrations of a compound formula (B) (as potential inhibitor) is carried out on a incubator shaker at 37 C. Standard incubation mixtures comprise NADPH and substrates in 100 mM phosphate buffer (pH 7.4) in a total volume of 200 μl. Test compound are dissolved in acetonitrile. Incubated with pooled human liver microsomes at 37.degree. C. for a defined time. The reactions are stopped by adding 100 μl of acetonitrile in which a suitable internal standard is always present. Precipitated proteins are removed by centrifugation, and the supernatants analyzed by LC-MS/MS. The data represents the extrapolated IC 50 (μM) concentration derived from 3 μM.
TABLE 5
CYP inhibition studies
IC 50 (μM) of CYP isoforms
CYP
Test
Isoforms
Product(formula B)
Rivaroxaban
1A2
1.4
18.9
3A4
5.7
9.7
2C9
22.4
16.7
2C19
25.3
13.2
2J2
6.7
No inhibition
2D6
8.2
13.2
Interpretation
Low drug-drug interaction (compound formula-B
with other drug) when administered.
Permeability in caco2 system
Efflux
Papp (10 −6 cm/sec)
ratio
Compound
A > B
B > A
(B > A/A > B)
derivative
17.41
40.3
2.31
Interpretation
Derivative showed high permeability.
Classification based on Papp.
Derivative showed efflux of >2 and
observed to be a Pgp substrate.
(10 −6 cm/sec) <2 = low, 2-20 = medium, >20 = high
Table-5 indicates that the CYP inhibition study using probe substrate method was carried out to determine the concentration required to inhibit different CYP isoforms. This is an essential parameter to gauge drug-drug interactions. The compound of formula B showed minimal inhibition of the CYP isoforms (>1 uM) that were assayed.
3. In Vitro Liver Microsomal Stability Assay
Liver microsomal stability assays are conducted at 1 mg per mL liver microsome protein with an NADPH in phosphate buffer (100 mM, pH 7.4). Test compounds (compound of formula B of the invention) are prepared as solutions in 20% methanol-water and added to the assay mixture (final assay concentration 1 μM) and incubated at 37.degree. C. Aliquots (100.μ·L) are taken out at times 0, 15, and 30 minutes, and diluted with ice cold acetonitrile containing IS (200.mu·L) to stop the reactions. Samples are centrifuged at 10,000 RPM for 5 minutes to precipitate proteins. Supernatants are transferred to micro centrifuge tubes and stored at −20° C. for analysis of LC/MS/MS. The percent parent remaining of the test substance is calculated as Ratio of peak area at each time point to peak area ratio at zero min, multiplied by 100. The compound formula (B) is converted to Rivaroxaban in microsomal assay.
Table-6
Represent Microsomal stability in Human, Rat and Mouse of the test compound (formula-B) and rivaroxaban.
TABLE 6
Microsomal stability in Human, Rat and Mouse of the test compound(formula-B) and rivaroxaban
% Parent remaining (Human)
% Parent remaining(rat)
Test Product
Test Product
Test
Rivaroxaban
Test
Rivaroxaban
Time(min)
Product
formation*
Rivaroxaban
Product
formation
Rivaroxaban
0
—
100
100
—
100
100
15
—
100
0.01
—
19.78
0.01
30
—
66.2
0.01
—
5.20
0.02
%
Metabolised to
Rivaroxaban
99.99%
Metabolised to
Rivaroxaban
99.98%
metabolised
rivaroxaban, seen
formation in
metabolised
rivaroxaban is
formation in
metabolised
from zero min.
Test substance
seen from zero
Test substance
Neglible amount
microsomal
min. Neglible
in microsomal
of test product
protein. Formed
amount of test
assay. The formed
detected
rivaroxaban is
product detected
Rivaroxaban is
metatabolied
metabolised
(44.8%)
(94.8%)
Observation
Formation of
High
Formation of
High
rivaroxaban from start
metabolism
rivaroxaban from start
metabolism
of the reaction and
of the reaction and
formed rivaroxaban is
formed rivaroxaban is
stable in human
shown metabolism
microsome
% Parent remaining(Mouse)
Test Product
Test
Time(min)
Product
Rivaroxaban
Rivaroxaban
0
—
100
100
15
—
41.93
0.03
30
—
25.70
0.02
%
metabolised to
Rivaroxaban
99.98%
metabolised
rivaroxaban is
formation in
Metabolised
seen from zero
Test substance
min. Neglible
in microsomal
amount of test
assay. The formed
product detected
Rivaroxaban is
metabolised
(74.3%)
Observation
Formation of
High
rivaroxaban from start
metabolism
of the reaction and
formed rivaroxaban is
shown metabolism
The findings seen in Table 6 suggest that the Test compound formula B is rapidly metabolized across species in rat, mouse and human microsomes. There is immediate conversion to rivaroxaban seen in this microsomal stability experiment by LCMS. The formed Rivaroxaban was also observed to metabolized in the microsomal experiment across species
4. Determination of Plasma Protein Binding
A compound solution (1 mM in DMSO) (5 μL), according to the invention is added to the respective plasma matrices of rat or human or mouse (1 ml).
Add 150 ul of phosphate buffer to receiving side of the dialysis well. Add 150 μl of plasma spiked with 5 μM compound formula (B) to the sample side of the dialysis well, dialyse for 6 h. Precipitate with Acetonitrile and dilute samples prior to analysis in 1.5 ml polypropylene tubes. Remove 50 μl from the sample side of dialysis well and add 50 μl of phosphate buffer +300 μl of acetonitrile containing IS. Remove 50 μl from the buffer side of the dialysis well and add 50 μl of respective matrix plasma +300 μl of ACN. Then vortexed and centrifuged for 5 min, and supernatant is taken and injected into LCMS.
Different test concentration ranging from 0.1 μM to 20 μM are made in methanol:water (90:10). Test solutions are added to the premixed matrix containing plasma:phosphate buffer (50:50). Precipitate with 300 μl of ice cold acetonitrile containing IS, vortexes and centrifuged. Supernatant is taken and injected into LCMS.
Percentage of plasma protein binding was obtained via Equation(2):% Fraction unbound=(concentration on the buffer side/concentration on the sample side)*100
Table-7
Represent protein binding in Human Rat and Mouse, The plasma protein binding assay of the formula B, was determined in plasma matrix with different species from rat, mouse and human. This is intended to see compound formula B, plasma binding as well as to see whether the conversion of the formula B, compound to rivaroxaban in plasma matrix across species from mouse, rat to human. There was a rapid conversion seen to rivaroxaban in experimental conducted with all three species. Negligible amount of the compound of formula B, was observed in-vitro plasma stability experiment and rapid conversion to rivaroxaban observed at in-vitro conditions across species. The formed rivaroxaban is also bound to plasma protein across species.
TABLE 7 Protein Binding in Human, Rat and Mouse of the test compound (Formula-B) and quantification of rivaroxaban Human Rat Mouse. Test Product Test Product Test Product Test Rivaroxaban Test Rivaroxaban Test Time(hr) Product formation Product formation Product Rivaroxaban Free NA 1.34 NA 9.39 NA 8.41 fraction (%) % Binding NA 98.66 NA 96.61 NA 91.59 Observation Not quantificable amount Not quantificable amount Not quantificable amount of test product. Based on of test product. Based on of test product. Based on plasma stabilty, there is a plasma stabilty, there is a plasma stabilty, there is a conversion to rivaroxaban conversion to rivaroxaban conversion to rivaroxaban and formed Rivaroxaban and formed Rivaroxaban and formed Rivaroxaban found to be High bound to found to be moderate-High found to be moderate-High plasma protein. Formed bound to plasma protein. bound to plasma protein. Rivaroxaban from test Formed Rivaroxaban from Formed Rivaroxaban from product is similar protein test product is comparitively test product is similar binding to rivaroxaban low protein binding to protein binding to alone. Rivaroxaban alone. Rivaroxaban alone.
5. Intravenous and Oral Pharmacokinetics in Wistar Rats:
On the day before administration of the substance, a catheter for obtaining blood is implanted in the jugular vein of the experimental animals (male Wistar rats, body weight 200-250 g) under Isofluran® anesthesia.
On the day of the experiment, a defined dose of the compound formula (B) is administered as solution into the tail vein as a bolus administration and oral administration takes place as a suspension or solution. Blood samples (8-12 time points) are taken through the catheter sequentially over the course of 24 h after administration of the substance. The administration volume is 10 ml/kg for oral and 1 ml/kg for IV in male Wistar rats. Intravenous administration is via a formulation of 2% N—N Dimethyl acetamide/ethanol 10%/PEG400 (30%)/water for IV injection (58%) and via Tween80/PEG400/sterile water in the case of oral administration. Removal of blood is after 0.08, 0.25, 0.5, 1, 2, 3, 4, 6, 8 and 12 hours in the case of IV and, blood withdrawn after 0.25, 0.5, 1.0, 2, 3, 4, 6, 8 and 12 hours for oral administration.
Plasma is obtained by centrifuging the samples in heparinized tubes. IS containing Acetonitrile is added to a defined plasma volume per time point to precipitate proteins. After centrifugation, compound formula (B) and, where appropriate, known cleavage products of the compound formula (B) in the supernatant are determined quantitatively using a suitable LC/MS-MS method.
The measured plasma concentrations are used to calculate pharmacokinetic parameters of the test substance and of the active ingredient compound (A) liberated there from, such as AUC, C.sub.max, T.sub.½ (half-life) and CL (clearance).
After i.v. administration of the compounds, the test substance was no longer detectable in plasma even at the first measurement point. Only the active ingredient was detectable up to the 24-hour time point too.
After oral administration of the compounds, these substances were no longer detectable in plasma even at the first measurement point. Only the active ingredient (Example 1) was detectable up to the 24-hour time point too.
Acetonitrile containing IS is added to the study samples, calibration samples and QCs, and the protein is precipitated using acetonitrile. Vortexed and centrifuged at 4000 rpm and the supernatant is injected by LC-MS/MS (API 4000, AB Sciex). Chromatographic separation is carried out on an Shimadzu UFLC. The injection volume is 10 μl. The separation column used is a Phenomenex Gemini NX 4.6×5μ. 100 mm, adjusted to a temperature of 30.degree. C. A binary mobile phase gradient at 800.mu·l/min is used (A: 0.1% formic acid in water, B: acetonitrile: API 4000, ESI Agilent 1100 column: Gemini Nx 100 mm×4.6 mm 5.μ; column temperature: 30° C.; eluent A: 0.1% formic acid in water, eluent B: acetonitrile; gradient: 0-2.5 min 95% A, 5% B; 2.5-2.6 min 5% A, 95% B; 2.6-4.2 min 95% A, 5% B; flow rate: 0.8 ml/min; ESI. Q1:464.098, Q3:144.255 The temperature of the Turbo V ion source is 500.degree. C. The following MS instrument parameters are used: curtain gas 20 units, ion spray voltage 5 kV, gas 1 50 units gas 2 50 units, CAD gas 6 units. The substances are quantified by peak heights or areas using extracted ion chromatograms of specific MRM experiments.
The plasma concentration/time plots determined are used to calculate the pharmacokinetic parameters such as AUC, C.sub.max, MRT (mean residence time), t.sub.½ (half life) and CL (clearance) employing the validated pharmacokinetic calculation programs.
6. Suspension for Intravenous Administration:
Composition:
2.2 mg of the compound according to the invention, 0.22 of ethanol (10%), 0.66 ml of PEG400 (30%), 1.27 ml of water for injection (58%) and 0.04 ml of 2% N—N-dimethyl acetamide.
A single dose of 1 mg of the compound according to the invention corresponds to 1 ml of intravenous solution.
Preparation:
The required quantity of the test compound is weighed in glass vial. To this, N, N dimethyl acetamide was added and vortexed. Then ethanol, PEG400 was added and vortexed. Finally, water for injection is added, mixed, vortexed and sonicated to achieve the final concentration of 1 mg/ml. The final solution was clear and colorless in appearance.
7. Solution for Oral Administration:
Composition:
8.3 of the compound formula (B), Tween 80, PEG400 and sterile water for injection was added. The required quantity of the test compound is weighed in glass vial. To this, N, N dimethyl acetamide was added and vortexed. Then ethanol, PEG400 was added and vortexed. Finally, water for injection is added, mixed, vortexed and sonicated to achieve the final concentration of 1 mg/ml. The final solution was clear and colorless in appearance
Preparation:
The required quantity of the compound formula (B) is weighed in glass vial. To this, Tween 80 was added and vortexed. Then ethanol, PEG400 was added and vortexed. Finally, water for injection is added, mixed, vortexed and sonicated to achieve the final concentration of 0.5 mg/ml. The final solution was clear and colorless in appearance.
Concentration-time profile of Rivaroxaban following intravenous administration of test compound at a dose of 10 mg/kg.
TABLE 8 Rivaroxaban alone PK Mean IV Mean PO parameter Unit (1 mg/kg) (10 mg/kg) F [%] n.c. 81.99 AUC(0-t) [ng/mL*h] 1002.09 8481.44 AUC [ng/mL*h] 1102.73 9040.96 Δ AUC [%] 7.11 6.01 C0(tdose) [ng/mL] 581.14 n.c. C(max) [ng/mL] n.c. 1420.27 t(max) [h] n.c. 1.42 t(½, z) [h] 6.08 5.70 MRT [h] 3.38 6.29 CL [mL/min/kg] 25.33 18.75 V(z) [L/kg] 10.72 9.13
Concentration-time profile of Rivaroxaban following oral administration of test compound at a dose of 10 m/kg
TABLE 9
Derivative (Rivaroxaban formed on dosing of derivative)
PK
Mean IV
Mean PO
parameter
Unit
(1 mg/kg)
(10 mg/kg)
F
[%]
n.c.
26.95
AUC(0-t)
[ng/mL*h]
3859.31
10398.42
AUC
[ng/mL*h]
3906.91
10530.40
Δ AUC
[%]
1.51
1.49
C0(tdose)
[ng/mL]
559.12
n.c.
C(max)
[ng/mL]
n.c.
2022.31
t(max)
[h]
n.c.
1.67
t(½, z)
[h]
6.61
3.69
MRT
[H]
2.50
4.97
CL
[mL/min/kg]
4.47
17.63
V(z)
[L/kg]
2.78
5.84
Table 8 and 9 indicate that compound formula B showed an increased exposure in terms of AUC as well as increased C max as compared to Rivaroxaban. This suggests that compound formula B is quickly absorbed and immediately converted to Rivaroxaban.
8. Determination of Anticoagulant Activity
The anticoagulant action of the test substance (compound formula-B) and rivaroxaban was determined in vitro using human plasma. The human plasma used for this experiment was separated from the blood collected in sodium citrate as anticoagulant. The prothrombin time (PT) was determined by using a commercial test kit (Neoplastin from Stagid) and APTT was determined using (Synthasil kit by IL). Different concentrations of test substance and rivaroxaban used were from 0.1 to 1.0 μg/mL along with corresponding solvent as control. For determination of PT the test compound and Rivaroxaban were incubated with the plasma at 37° C. for 10 minutes. Coagulation was then started by addition of thromboplastin, and time when coagulation occurred was determined. The concentration of test substance which effected a doubling of prothrombin time was determined. For determination of a PTT the test compound and Rivaroxaban were incubated with the plasma at 37° C. for 10 minutes after which CaCl2 was added. The results of assay indicated that the test compound (compound formula-B) has significant anticoagulant activity.
In an embodiment of this invention, the compound of formula B can be comprised in medicament normally together with one or more inert, non-toxic, pharmaceutically suitable excipients and to the use thereof for the aforementioned purposes.
The compounds can be administered to act systemically and/or locally. For this purpose, they can be administered in a suitable way and form such as, for example, by the oral, parenteral, pulmonary or nasal route, preferably orally.
Suitable for oral administration are administration forms which function according to the prior art and deliver the compound according to the invention rapidly and/or in modified fashion, and which contain the compounds according to the invention in crystalline and/or amorphous and/or dissolved form, such as, for example, tablets (uncoated or coated tablets, for example having enteric coatings or coatings which are insoluble or dissolve with a delay and control the release of the compound according to the invention), tablets which disintegrate rapidly in the mouth, or films/wafers, films/lyophilizates, capsules (for example hard or soft gelatin capsules), sugar-coated tablets, granules, pellets, powders, emulsions, suspensions, aerosols or solutions.
9. Intravenous and Oral Excretion Profile in Wistar Rats:
On the day before administration of the substance, a catheter for obtaining blood is implanted in the jugular vein of the experimental animals (male Wistar rats, body weight 200-250 g) under Isoflurane. anesthesia.
On the day of the experiment, a defined dose of the compound formula (B) is administered as solution into the tail vein as a bolus administration and oral administration takes place as a suspension or solution. Urine and faeces are taken collected from metabolic cages over the course of 144 h after administration of the substance. The administration volume is 10 ml/kg for oral and 1 ml/kg for IV in male Wistar rats. Intravenous administration is via a formulation of 2% N—N Dimethyl acetamide/ethanol 10%/PEG400 (30%)/water for IV injection (58%) and via Tween80/PEG400/sterile water in the case of oral administration. Urine and faeces collection is 0-4, 4-8, 8-24, 24-48, 48-72, 72-96, 96-120, 120-144 in the case of IV and for oral administration.
Urine and faeces was processed and IS containing Acetonitrile is added to a defined urine/faeces and precipitated. After centrifugation, compound formula (B) and, where appropriate, known cleavage products of the compound formula (B) in the supernatant are determined quantitatively using a suitable LC/MS-MS method.
The measured urine and faeces concentrations are used to calculate parameters of the test substance and of the active ingredient compound (A) liberated there from, such as AUC and C.sub.max.
After i.v. administration of the compounds, the test substance was no longer detectable in urine and faeces even at the first measurement point. Only the active ingredient was detectable up to in both urine and faeces.
After oral administration of the compounds, these substances were no longer detectable in urine and faeces even at the first measurement point. Only the active ingredient (Example 1) was detectable in urine as well as in faeces.
Acetonitrile containing IS is added to the study samples, calibration samples and QCs, and the protein is precipitated using acetonitrile. Vortexed and centrifuged and the supernatant is injected by LC-MS/MS (API 4000, AB Sciex). Chromatographic separation is carried out on an Shimadzu UFLC. The injection volume is 10 μl. The separation column used is a Phenomenex Gemini NX 4.6×5μ. 100 mm, adjusted to a temperature of 30.degree. C. A binary mobile phase gradient at 800.mu·l/min is used (A: 0.1% formic acid in water, B: acetonitrile: API 4000, ESI Agilent 1100 column: Gemini Nx 100 mm×4.6 mm 5.μ; column temperature: 30° C.; eluent A: 0.1% formic acid in water, eluent B: acetonitrile; gradient: 0-2.5 min 95% A, 5% B; 2.5-2.6 min 5% A, 95% B; 2.6-4.2 min 95% A, 5% B; flow rate: 0.8 ml/min; ESI. Q1:464.098, Q3:144.255 The temperature of the Turbo V ion source is 500.degree. C. The following MS instrument parameters are used: curtain gas 20 units, ion spray voltage 5 kV, gas 1 50 units gas 2 50 units, CAD gas 6 units. The substances are quantified by peak heights or areas using extracted ion chromatograms of specific MRM experiments.
10. Suspension for Intravenous Administration:
Composition:
2.2 mg of the compound according to the invention, 0.22 of ethanol (10%), 0.66 ml of PEG400 (30%), 1.27 ml of water for injection (58%) and 0.04 ml of 2% N—N-dimethyl acetamide.
A single dose of 1 mg of the compound according to the invention corresponds to 1 ml of intravenous solution.
Preparation:
The required quantity of the test compound is weighed in glass vial. To this, N, N dimethyl acetamide was added and vortexed. Then ethanol, PEG400 was added and vortexed. Finally, water for injection is added, mixed, vortexed and sonicated to achieve the final concentration of 1 mg/ml. The final solution was clear and colorless in appearance.
11. Solution for Oral Administration:
Composition:
compound formula (B), Tween 80, PEG400 and sterile water for injection was added. The required quantity of the test compound is weighed in glass vial. To this, N, N dimethyl acetamide was added and vortexed. Then ethanol, PEG400 was added and vortexed. Finally, water for injection is added, mixed, vortexed and sonicated to achieve the final concentration of 1 mg/ml. The final solution was clear and colorless in appearance
Preparation:
The required quantity of the compound formula (B) is weighed in glass vial. To this, Tween 80 was added and vortexed. Then ethanol, PEG400 was added and vortexed. Finally, water for injection is added, mixed, vortexed and sonicated. The final solution was clear and colorless in appearance.
Concentration-time profile of Rivaroxaban following intravenous administration of test compound (compound formula B) at a dose of 1 mg/kg and oral administration of test compound at a dose of 10 mg/kg
TABLE 10 (A)
Animal
Dose
Dose
Sample
weights
Dose
volume
conc.
Dosing
Number of
time (h) for
Group
(g)
(mg/kg)
(mL/kg)
(mg/mL)
route
animals
urine/faeces
1
250-300
1
1
1
i.v.
3
0-4, 4-8, 8-24,
24-48, 48-72,
72-96, 96-120,
120-144
2
250-300
10
10
1
p.o.
3
0-4, 4-8, 8-24,
24-48, 48-72,
72-96, 96-120,
120-144
TABLE 10 (B)
Rivaroxaban
Rivaroxaban
Derivative
Derivative
(IV 1 mg/Kg)
(PO 10 mg/Kg)
(IV 1 mg/Kg)
(PO 10 mg/Kg)
Mean
Mean
Mean
Mean
Mean
Mean
Mean
Mean
Time
(ng)
(ng/G)
(ng)
(ng/G)
(ng)
(ng/G)
(ng)
(ng/G)
[h]
Urine
Faeces
Urine
Faeces
Urine
Faeces
Urine
Faeces
4
559.4
442.8
2381.3
5458.8
345.5
3122.7
1200.6
9675.3
8
28.9
1442.0
1770.9
19583.2
447.0
911.6
1828.5
11184.7
24
169.4
1328.8
1838.1
236961.7
451.5
614.6
3296.0
6274.2
48
333.6
342.8
464.5
35049.4
24.6
164.5
1166.5
4881.3
72
539.5
110.7
236.1
6655.8
20.0
7.4
130.8
360.4
96
41.9
32.6
22.9
2291.2
7.1
3.3
92.5
5.0
120
BLQ
40.3
48.4
63.9
BLQ
5.2
30.6
45.0
144
BLQ
16.8
30.4
57.4
4.2
BLQ
29.7
70.7
TABLE 10 (C)
Summary Results
oral(10 mg/kg)
IV(1 mg/kg)
rivaroxaban
derivative
rivaroxaban
derivative
urine(ng)
6720.4
7744.6
1425.9
1152.8
faeces(ng/g)
408546.9
32503.0
2937.9
4974.9
plasma-AUC
9041.0
10530.4
1102.7
3906.9
Mean Urine AUC
76389.7
121079.3
20998.3
55548.0
Mean Faeces AUC
8189000.0
354379.0
12537.0
30631.7
Tmax
1.4
1.7
581.2
559.1
Table 10 (A), 10 (B) and 10 (C), indicate that, Plasma exposure is higher in Test product (compound formula-B) than the Rivaroxaban. The Urine excretion profile of Rivaroxaban and test compound (compound formula-B) showed similar excretion profile but the unabsorbed rivaroxaban is lesser on oral administration of Test product (compound formula-B).
Compound formula (B), showed lesser amount of rivaroxaban present in faeces as compared to rivaroxaban alone. Which indicate that an advantageous in having higher exposure in plasma and lower excretion in faeces as compared to rivaroxaban.
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The present invention relates to the prodrug of 5-chloro-N-({(5S)-2-oxo-3-[4-(3-oxo-morpholin-4-yl)phenyl]-1,3-oxazolidin-5-yl}methyl)thiophene-2-carboxamide, rivaroxaban per se; processes for their preparation, and the application in treatment and/or prophylaxis of diseases, especially of thromboembolic disorders. The prodrug of a compound of formula (B) is chemically designated as 5-chloro-N-formyl-N-({(5S)-2-oxo-3-[4-(3-oxomorpholin-4-yl)phenyl]-1,3-oxazolidin-5-yl}methyl)thiophene-2-carboxamide.
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CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional Patent Application 60/451,359 entitled “Marking Tape Measure” by Gary Pritchard filed Feb. 27, 2003, the entire content of which is hereby incorporated by reference herein for all it discloses and teaches.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention pertains to measuring devices and specifically to measuring devices capable of making markings.
[0004] 2. Description of the Background
[0005] Framers and construction workers typically have to measure and mark boards and panels during the layout and construction of buildings. Typically, the markings for building studs may occur every sixteen or twenty-four inches. The markings are routinely laid out by extending a tape measure and marking at periodic intervals with a pencil. The task of marking boards and panels is time consuming, as it requires traversing the entire length of a board to make the required marks.
[0006] For example, in the case where the top of an unfinished wall is to be marked, the framer may have to move a ladder every three or four feet along the wall in order to make the required layout marks to attach roofing trusses or the like. Every few feet, the framer may have to set up a ladder, climb the ladder, make the few marks that are within arm's reach, descend the ladder, move the ladder, and repeat the process.
[0007] It would therefore be advantageous to provide a system and method for creating markings on surfaces, such as boards, panels, or walls at specific intervals in a fast and efficient manner. It would further be advantageous if the system and method were compact, portable, and easy to use in difficult places.
SUMMARY OF THE INVENTION
[0008] The present invention overcomes the disadvantages and limitations of the prior art by providing a system and method for placing marks on surfaces including boards, panels, or walls in specific intervals in a single operation. A tape measure and chalk line dispenser allows the simultaneous extension of a measuring tape and chalk line. The measuring tape has a plurality of holes disposed along the tape at the specific intervals for marking. The chalk line is disposed above the tape and is tightened and snapped to create chalk marks through the holes and onto the board or panel. The tape and chalk line may then be rewound.
[0009] The tape may have a series of offset holes near the end of the tape that may allow a carpenter to offset the tape and thus the markings by a specific interval. Such offsets may be helpful in certain situations.
[0010] An embodiment of the present invention comprises a device for making at least one mark comprising: a length of tape having at least one hole disposed along the length at a predetermined location; a line disposed along the length such that at least a portion of the line spans the at least one hole; and a marking medium attached to the line.
[0011] Another embodiment of the present invention comprises a device for marking a plurality of marks comprising: means for masking having a plurality of holes disposed along the length of the means for masking at predetermined intervals; and means for dispensing a marking medium disposed along the length of the means for masking and further positioned such that at least a portion of the marking medium passes through the plurality of the holes.
[0012] Yet another embodiment of the present invention comprises a method for making at least one mark on a surface comprising: extending a tape having at least one hole over the surface; spanning the at least one hole with a marking line having a marking medium; withdrawing the marking line from the tape; allowing the marking line to snap onto the tape such that at least some of the marking medium passes through the at least one hole onto the surface.
[0013] The advantages of the present invention are that markings at specific intervals may be made with one motion. Further, the markings may be made from one end of the board without requiring traversing the length of the board to make a mark at every interval.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] In the drawings,
[0015] FIG. 1 is a partial cut away side view illustration of an embodiment of the present invention of a marking apparatus.
[0016] FIG. 2 is a partial cut away front view illustration of the embodiment of a marking apparatus shown in FIG. 1 .
[0017] FIG. 3 is a perspective view of an embodiment of the present invention of a marking apparatus.
[0018] FIG. 4 is a perspective view of the embodiment of the present invention of a marking apparatus shown in FIG. 3 .
[0019] FIG. 5 is a perspective view of an embodiment of the present invention of a marking apparatus showing the marking components.
[0020] FIG. 6 is a perspective view of an embodiment of the present invention of a marking apparatus having detachable components.
DETAILED DESCRIPTION OF THE INVENTION
[0021] FIG. 1 illustrates a cut away side view of an embodiment 100 of a marking apparatus. The body 102 contains a tape spool 104 and a chalk line spool 106 . As the free end tip 108 is pulled away from the body 102 , the tape 110 and chalk line 112 are extended with the chalk line 112 being located over or spanning the tape 110 . The tape 110 has a series of marking holes 114 at predetermined intervals. The tape 110 and chalk line 112 can be simultaneously retracted into the body 102 by the rewind crank 116 . The chalk line 112 travels through holes in stanchions 118 and 120 and tensioner 112 .
[0022] In operation, one places the tip 108 of the device over the edge of a surface to be marked, then extends the tape 110 and chalk line 112 simultaneously along the length to be marked. When the tape in the marking apparatus 100 is extended over the length to be marked, the body 102 may be placed on top of the surface such that the lower arm 124 of the tensioner 112 is pressed against the surface. The tensioner 112 forces the chalk line 112 against the tape with the tensioning arm 126 . The exposed chalk line 112 is stretched between stanchions 118 and 120 with one hand and the chalk line 112 is lifted and quickly released against the tape 110 with the other hand, allowing the chalk line to return to its normal position in a process known as ‘snapping the line.’ The chalk dust that is supported on the chalk line 112 transfers through the marking holes 114 and make marks on the board at those intervals.
[0023] The tape 110 may be a standard metal measuring tape that has markings typical to commercially available measuring tapes. The tape 110 may be constructed of steel or other metal, or may be constructed of plastic or other suitable material.
[0024] The marking holes 114 may be placed at periodic intervals that may be useful to those of the building trades. For example, it is common to mark studs and other building components on sixteen or twenty four inch intervals. Thus, the marking holes 114 may be placed at those intervals. In addition, it is often necessary to offset those intervals by a standard amount, such as one half of the width of a stud. Additional offset holes may be provided near the tip 108 to offset the marking holes 114 . A nail may be placed in the board and one of the offset holes may be placed over the nail to offset the markings a particular distance. For example, an offset of three-quarters of an inch may be desirable for laying out stud placement. A nail may be placed in the end of the board and an offset hole that is three-quarters of an inch from the tip 108 may be placed over the nail. Thus, for the entire length of the tape, all of the markings can be offset by three quarters of an inch. Other offsets may be accomplished by providing offset holes at predetermined locations along the tape. In another embodiment, the tape 110 may have a series of offset holes through which a nail may be inserted. The nail may then be placed over the edge of a board to offset the markings made by the embodiment 100 . In still other embodiments, the tip 108 may be movable such that it may be adjusted to different positions along the axis of the tape 110 in order to offset the marks made by the embodiment 100 .
[0025] The chalk line 112 may be a common string that is stored on a chalk line spool 106 . The chalk line spool 106 may be enclosed by a chalk compartment in which chalk is stored and by which chalk may become entrained by the string. In other embodiments, the string may be replaced by a woven band with a width greater than its thickness that may be able to produce marks wider than would be possible with a string.
[0026] The marking holes 114 may be small circular holes or may be a specially shaped hole that may produce a specially shaped mark. Such shapes may include numerical shapes that may mark the location with a numerical designation. In other embodiments, the marking holes 114 may include a mark for the edge of a stud or other building member and a second mark or designation for the side to which the stud is to be placed. It is common for a carpenter to mark a location with a line or crow's foot mark and then place an ‘X’ to designate the appropriate side of the line for the stud. Such marks may be placed by an embodiment of the present invention having an ‘X’ shaped hole.
[0027] The tensioner 112 operates by rotating about the hinge point 128 . As the body 102 is placed upon a surface, the lower arm 124 causes the tensioner 122 to rotate and slightly stretch the chalk line 112 with the tensioning arm 126 . In some embodiments, the amount of tension applied by the tensioning arm 126 may be sufficient to snap the chalk line 112 and effectively place marks along the board. In other embodiments, the carpenter may push the body 102 against the board and pull the chalk line 112 taught by pulling on the chalk line 112 in the area between the stanchions 118 and 120 .
[0028] The rewind crank 116 may be used to retract the tape 110 and chalk line 112 into the body 102 . The rewind crank 116 may be connected to the tape spool 104 and chalk line spool 106 by various gears, pulleys, or other mechanisms such that the tape 110 and chalk line 112 may be retracted substantially simultaneously. In other embodiments, a return spring may be used in place of the rewind crank 116 . In such embodiments, the tape spool 104 and chalk line spool 106 may be connected by a mechanism that allows for the simultaneous retraction of the tape 110 and chalk line 112 .
[0029] FIG. 2 is a partial cut away front view of the embodiment 100 of a marking apparatus. The body 202 has a tape housing 204 and a chalk line housing 206 . The return crank 208 is mounted so that it can retract the chalk line and tape into the body 202 . The chalk line 210 is fed through stanchions 214 and 216 to the tip 212 . The wall 218 separates the chalk line housing 206 from the tape housing 204 . The chalk line housing 206 may have a door into which may poured a quantity of chalk dust. The chalk dust may then become entrained on the chalk line 210 .
[0030] Various embodiments may have different mechanisms for handling the chalk dust. For example, wipers and mechanisms of various sorts may be employed to remove excess chalk dust from the tape or chalk line. Such mechanisms regulate the amount of chalk that is entrained on the chalk line and to clean the tape during rewind to prohibit chalk dust from collecting inside the tape housing 204 .
[0031] FIG. 3 illustrates a perspective view of an embodiment 300 of the present invention of a marking apparatus. The body 302 contains a tape spool 304 and a string spool 306 . A tape locking lever 308 allows the tape to be locked in a particular position. A chalk filling door 310 may be opened to receive powdered chalk that can be carried on the string 314 . The free end of the tape 312 may be hooked over the edge of a piece of wood or other article to be measured or marked. The string end clip 316 may be engaged on the post 317 when the device is used as a marking instrument.
[0032] The embodiment 300 may be used as a separate tape measure and string line. For example, to use the embodiment 300 as a tape measure, the string end clip 316 may be disengaged from the tape end clip 312 and stored in the string end clip holder 318 . The tape may be extended from the tape spool 304 by pulling on the tape end clip 312 . The tape may be an elongated sheet of metal or plastic and may have graduations, marks, or other indicia for measuring or otherwise indicating distance. Similarly, the tape may be kept in the retracted position and the string may be extended to mark or indicate a straight line.
[0033] FIG. 4 illustrates a perspective view of an embodiment 400 of the present invention of a marking apparatus. The body 402 contains a tape spool 404 and a string spool 406 . A tape locking lever 408 may lock the tape in a particular position. A chalk filling door 410 may be opened to receive powdered chalk or other marking medium that can be carried on the string 414 . The tape end clip 412 has a post 417 that may receive the string end clip 416 .
[0034] The embodiment 400 contains a string retract crank 418 that may engage the string spool 406 to retract the string 414 into the body 402 . In some embodiments, the crank 418 may engage the string spool directly or may engage the spool by means of gears.
[0035] In some embodiments, the tape may be retracted by a spring mechanism. In some embodiments, the string and the tape may be retracted simultaneously and collectively by a gear mechanism between the tape spool and the string spool. In other embodiments, the tape and the spring may be retracted separately and using separate devices. For example, the tape may be retracted with a spring powered mechanism while the string is retracted by a hand crank mechanism. Various retraction mechanisms may be used by those skilled in the art while keeping within the spirit and intent of the present invention.
[0036] The string 414 may carry chalk or other marking medium and may be used to transfer the marking medium to an article to be marked. In some instances, the string may contain powdered chalk, powdered ink, liquid ink, or other marking fluid or powder.
[0037] FIG. 5 illustrates a perspective view of an embodiment 500 of the present invention of a marking apparatus. A measuring tape 502 contains a plurality of apertures 504 at predetermined intervals or other spacing. The tape clip 506 may be hooked over the edge of an article to mark. A chalk line 5 10 may be placed over the tape 502 by engaging the string end clip 512 over the post 508 of the tape end clip 506 . The string 510 is placed directly on top of the tape 502 , spanning the apertures 504 . When the string 510 is made taught, the chalk line 5 10 may be raised and released quickly to transfer the marking medium carried by the chalk line 510 through the apertures 504 and onto the item to be marked. This process is sometimes called ‘snapping a line’ in the trade.
[0038] The apertures 504 may be selected to be of various shapes, sizes, and spacing to indicate various distances or marks as those skilled in the art may desire. For example, for framing houses in the United States, it may be conventional to mark studs at 16 inches apart. In such a case, the apertures 504 may be spaced 16 inches apart. In some cases, the shape of an aperture 504 may have a special meaning, such as the stud side of a mark.
[0039] In some cases, the measuring tape 502 may have various marks or indicia for measuring distance or other functions as desired.
[0040] FIG. 6 is a perspective view of an embodiment 600 of the present invention of a marking apparatus. A tape body 602 contains a tape 604 and a tape locking tab 606 . A chalk line body 608 contains a string 610 , a string end clip 612 , a retraction crank 614 , and a chalk filling door 616 . The chalk line body 608 may removably engage the tape body 602 with a locking/locating feature 618 .
[0041] The embodiment 600 allows the string line body 608 to be removed and separately used from the tape body 602 , but be recombined in order to use apertures in the tape 604 to mask the chalk line 610 to make separate, distinct marks along the length of the tape 604 . For example, the chalk line 610 may be used for marking a straight line while the tape measure 602 may be used to measure a certain distance. After such time, the chalk line 610 may be reattached to the tape measure 602 and used to mark a plurality of points along a distance.
[0042] Various locating and locking mechanisms 618 may be used by those skilled in the art while keeping within the spirit and intent of the present invention. For example, the tape measure 602 and the chalk line 610 may snap together, may lock together using a mechanical linkage, may slidingly engage each other, or any other type of releasable engagement device or mechanism.
[0043] 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 embodiments were 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.
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A marking device for making layout marks an surfaces such as boards, panels, or walls including a tape measure with a plurality of holes disposed along its length is disclosed. The device also contains a reel for dispensing a chalk line wherein the chalk line is positioned over the tape measure. The chalk line may be tensioned and snapped to transfer chalk through the holes, thereby providing marks at predetermined intervals.
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RELATED APPLICATIONS
The present application derives from and claims priority to U.S. Provisional Application No. 61/924,015, filed on Jan. 6, 2014, bearing the present title, and U.S. Provisional Application No. 62/020,672, filed on Jul. 3, 2014 entitled “Underwater Noise Abatement Apparatus with Simple Multi-Frequency Responsive Resonator Elements”, both of which are hereby incorporated by reference.
TECHNICAL FIELD
The present disclosure relates to the deployment of noise abatement devices for reduction of underwater sound emissions, such as noise from sea faring vessels, oil and mineral drilling operations, and marine construction and demolition.
STATEMENT REGARDING JOINT RESEARCH AGREEMENT
One or more inventions contained in this application were developed under a joint research agreement between The University of Texas at Austin and AdBm Technologies, LLC.
BACKGROUND
Various underwater noise abatement apparatuses have been proposed. Some are embodied in a form factor that encloses or is deployed at or near a source of underwater noise. Patent publication US 2011/0031062, entitled “Device for damping and scattering hydrosound in a liquid,” describes a plurality of buoyant gas enclosures (balloons containing air) tethered to a rigid underwater frame that absorb underwater sound in a frequency range determined by the size of the gas enclosures. Patent application Ser. No. 14/572,248, entitled “Underwater Noise Reduction System Using Open-Ended Resonator Assembly and Deployment Apparatus,” discloses systems of submersible open-ended gas resonators that can be deployed in an underwater noise environment to attenuate noise therefrom. These and their related applications and documentation are incorporated herein by reference.
Underwater noise reduction systems are intended to mitigate man-made noise so as to reduce the environmental impact of this noise. Pile driving for offshore construction, oil and gas drilling platforms, and sea faring vessels are examples of noise that can be undesirable and that should be mitigated. However, the installation, deployment and packaging of underwater noise abatement systems can be challenging, as these apparatus are typically bulky and cumbersome to store and deploy.
The present application is concerned with the packaging, storage, and deployment of underwater noise reduction devices.
SUMMARY
A deployment system for packing and deploying underwater noise reduction apparatus is disclosed. The system allows relatively compact storage and transportation of the noise abatement apparatus when not in use, then, when deployed, the apparatus can be lowered into the water and extended.
In an aspect, the system comprises a plurality of noise abating resonators, each resonator holding a gas therein and being responsive to acoustic energy in a vicinity of said resonator. The resonators are arranged into a deployable arrangement within a collapsible frame so that the deployable arrangement provides a deployed configuration of the resonators in the frame when the system is deployed, and a stowed configuration of the resonators in the frame when the system is not deployed. In the deployed configuration, the frame is in an extended position so that the resonators are spaced further apart from one another than they would be when stowed, and in the stowed configuration the frame is in a contracted position so that the resonators are spaced closer together than they would be when deployed.
In another aspect, a method for abating noise is disclosed. The method includes arranging a plurality of acoustic resonators in a flexible and deployable framework that can be configured in a deployed or in a stowed configuration. The method also includes extending the frame into its deployed configuration by extending the flexible frame when the framework is to be deployed into a volume in which noise is to be abated. The method also includes contracting the frame into its stowed configuration by compacting the flexible frame when the framework is to be stowed. The method also includes storing the deployable framework in a storage compartment when not deployed and when in its stowed configuration.
IN THE DRAWINGS
For a fuller understanding of the nature and advantages of the present concepts, reference is made to the following detailed description of preferred embodiments and in connection with the accompanying drawings, in which:
FIG. 1 illustrates an exemplary noise reduction apparatus panel;
FIG. 2 illustrates a vessel carrying and deploying a noise reduction apparatus;
FIG. 3 illustrates a detail of FIG. 2 ;
FIG. 4 illustrates a noise reduction apparatus panel in its stowed configuration;
FIG. 5A illustrates a perspective view of the panel of FIG. 4 in its deployed configuration;
FIG. 5B illustrates a perspective view of a row of resonators disposed in the apparatus of FIG. 5A ;
FIG. 6 illustrates storage and transportation of a noise reduction apparatus;
FIG. 7A illustrates a collapsed configuration of a noise reduction apparatus;
FIG. 7B illustrates an-expanded configuration of a noise reduction apparatus;
FIG. 8 illustrates the apparatus of FIGS. 7A and 7B in its fully deployed configuration;
FIG. 9 illustrates storage and transportation of the apparatus of FIG. 8 ;
FIG. 10A illustrates a perspective view of a self-collapsing noise reduction apparatus that expands and retracts when deployed or stowed;
FIG. 10B illustrates a perspective view of an upper portion of a self-collapsing noise reduction apparatus;
FIG. 10C illustrates a perspective view of a lower portion of a self-collapsing noise reduction apparatus;
FIG. 11 illustrates a perspective view of a self-collapsing noise reduction apparatus in a stowed configuration;
FIG. 12A illustrates a first perspective view of a self-collapsing noise reduction apparatus in a deployed configuration;
FIG. 12B illustrates a second perspective view of a self-collapsing noise reduction apparatus in a deployed configuration;
FIG. 13A illustrates a perspective view of a self-collapsing noise reduction apparatus in a stowed configuration before deployment in a water tank;
FIG. 13B illustrates a perspective view of a self-collapsing noise reduction apparatus in a deployed configuration after deployment in a water tank;
FIG. 14A illustrates a perspective view of a noise reduction apparatus in a deployed configuration;
FIG. 14B illustrates a perspective view of a noise reduction apparatus in a stowed-configuration;
FIG. 15A illustrates a perspective view of a noise reduction apparatus in stowed configuration connected to a support frame;
FIG. 15B illustrates a perspective view of a noise reduction apparatus in a deployed configuration connected to a support frame;
FIG. 16A illustrates a noise reduction apparatus in a stowed configuration mounted on an annular articulating frame in a lowered position;
FIG. 16B illustrates a noise reduction apparatus in a stowed configuration mounted on an annular articulating frame in a raised position;
FIG. 16C illustrates the noise reduction apparatus of FIG. 16B on an annular articulating frame in an open position for mounting on a pile;
FIG. 16D illustrates the noise reduction apparatus of FIG. 16C in a deployed configuration while the annular articulating frame is mounted on the pile;
FIG. 17A illustrates a perspective view of hanging a stowed noise reduction panel on an annular articulating frame;
FIG. 17B illustrates a perspective view of a plurality of stowed noise reduction panels hanging on an annular articulating frame;
FIG. 17C illustrates a perspective view of a plurality of stowed noise reduction panels hanging on an annular articulating frame in an open position for mounting on a pile;
FIG. 17D illustrates the noise reduction apparatus of FIG. 17C with the annular articulating frame mounted on the pile;
FIG. 17E illustrates the noise reduction apparatus of FIG. 17D in a deployed configuration; and
FIG. 18 illustrates a noise reduction apparatus disposed in a storage frame.
DETAILED DESCRIPTION
A plurality of noise-reducing resonators are disposed on a collapsible frame. The collapsible frame can be configured in a stowed arrangement and a deployed arrangement. In the stowed arrangement, the space between each resonator is reduced compared to the deployed arrangement. In the deployed arrangement, the space between each resonator is increased compared to the stowed arrangement. The resonators can be arranged in a two- or three-dimensional array. A rigging line can be used to transition the frame from/to the stowed arrangement to/from the deployed arrangement. The rigging line can be connected to a winch.
FIG. 1 illustrates an underwater noise reduction apparatus 10 . The noise reduction apparatus 10 can be lowered into a body of water around or proximal to a noise-generating event or thing such as a drilling platform, ship, or other machine. A plurality of resonators 102 on a panel 100 of the noise reduction apparatus 10 resonate so as to absorb sound energy and therefore reduce the radiated sound energy emanating from the location of the noise-generating event or thing. The resonators 102 include a cavity to retain a gas, such as air, nitrogen, argon, or combination thereof in some embodiments. For example, the resonators 102 can be the type of resonators disclosed in U.S. Ser. No. 14/494,700, entitled “Underwater Noise Abatement Panel and Resonator Structure,” which is hereby incorporated herein by reference. In some embodiments, the resonators 102 are arranged in a two- or three-dimensional array.
In the shown embodiment, the panel 100 is towed by lines 110 tethered to a tow point or line 120 . As an example, the apparatus can be towed behind a noisy sea faring vessel. Several such apparatuses can be assembled into a system for reducing underwater noise emissions from the vessel. Also, a system like this can be assembled around one or more facets of a mining or drilling rig.
FIG. 2 illustrates an exemplary sea faring vessel (e.g., a ship) 20 equipped to deploy a noise reducing apparatus 220 into the water. The ship 20 has a deck 200 and an articulated structural support member 202 at one end thereof. It is understood that the present example is but for the sake of illustration, and other embodiments and arrangements will be apparent to those skilled in the art.
The noise reducing apparatus 220 is expandable and deployable as described below. Using a line 212 , the noise reducing apparatus 220 can be lowered into and raised out of the water using a winch 210 and pulley 214 . The example illustrates a number of noise reducing apparatuses 220 A, 220 B, 220 C in their standby, collapsed, and stowed configurations 240 A, 240 B, 240 C, respectively. The crew of the ship can attach, hoist, and deploy the noise reducing apparatus 220 into the water as desired.
FIG. 3 shows a closer detail of the aft section 25 of vessel 20 . We see that line 212 can be used to raise and lower noise reduction apparatus 220 . The apparatus 220 drops under the weight of gravity. A plurality of rows 222 of resonators 202 are configured as shown so that they are flexibly coupled by rigging lines 224 allowing them to change from stowed (e.g., compact and folded) format 240 to an open format 220 when deployed. In the open format 220 , the rows 222 are spaced apart from one another at a predetermined distance 235 based on the length of rigging lines 224 between each row 222 . A top bar 226 can be made of metal with a buoyant material, such as a hard syntactic foam, attached thereto. This keeps a top portion 230 of the apparatus 220 separated and above lower cross member 228 to extend the rigging lines 224 so they are generally taut and the rows 222 spaced apart as discussed above.
As illustrated, the rows 222 are generally parallel with one another. The rows 222 generally extend along a first dimension 250 , which can be parallel to a surface of the ocean. The resonators 202 are also disposed in columns 226 , which generally extend in a second dimension 260 . The second dimension 260 can be generally orthogonal (e.g., within about 10%) to the first direction 250 . The second dimension 260 can be generally parallel (e.g., within about 10%) to the direction of gravitational pull.
FIG. 4 illustrates an exemplary noise reduction apparatus 300 in its stowed (compact and folded) configuration 305 . This configuration 305 takes up less space in the second dimension 260 (e.g., the vertical direction) to store the apparatus 300 and to make it easier to transport and/or to stack with other similar units in transit or storage. Upper cross member 310 is shown, and as mentioned above, can be constructed of metal with a buoyant material such as foam attached. Lower cross member 320 may be constructed of a metal material. In general, the metal material should be resistant to corrosion that would result from exposure to the ocean. Examples of such materials are stainless steel, aluminum, bronze, and combinations thereof. The metal material can also be comprised of something susceptible to corrosion such as steel, but treated with a galvanizing process, a powder coating, or the like.
Optional telescoping side support members or struts 340 can permit collapsing and expanding of the overall structure along the second dimension 260 (e.g., the vertical direction). The telescoping side support members 340 include a female portion 342 and a male portion 344 . The female portion 342 includes a cavity to receive the male portion 344 . The female and male portions 342 , 344 can slideably engage in a telescoping manner as the apparatus 300 expands from the stowed configuration 360 to a deployed configuration (e.g., as illustrated in FIG. 3 ). In the stowed configuration 360 , at least a portion of the male portion 344 is disposed in the female portion 342 .
Support lines 370 can hoist the apparatus 300 up and down (e.g., along the second dimension 260 ) while lines 360 allow the expansion and collapsing of the apparatus similar to a venetian blind. The “blinds” or “slats” 330 of the apparatus 300 may consist of a plurality of resonators in the form of inflatable pockets or compartments. In some embodiments the resonators are inverted open ended (having a downward facing open ‘mouth’) to hold a quantity of air or other gas in each resonator, as discussed above. The resonators can act as Helmholtz resonators to absorb underwater sound when deployed. In an embodiment, the resonators may include a conductive fluid-permeable mesh over the open end thereof that improves the noise absorption capabilities of the system through heat transfer associated with the resonance of gas in the resonators.
FIG. 5A shows an extended noise absorbing apparatus panel 400 as it would appear when deployed. It is clear that an essentially arbitrary number of resonators 410 can be arranged in resonator rows 420 of the apparatus panel 400 . The spacing and configuration of the resonators 410 can be flexibly designed according to the needs of the user of the apparatus 400 . The resonators 410 can be arranged in an array of rows 420 and columns 430 as illustrated. The rows 420 and columns 430 generally define a plane 440 .
FIG. 5B illustrates an exemplary configuration of resonators 410 (e.g., inflatable members) arranged in rows 420 of the apparatus of FIG. 5A in a fabric or rubber or other mesh or flexible belt strip 405 . The strip 405 can support the resonators 410 so they stay aligned generally in the row 420 .
FIG. 6 illustrates an exemplary way to stow and transport a plurality of noise absorbing resonator panels 400 , such as those described above, in a standard shipping container 500 . The roof of the container 500 is not illustrated in the drawing for clarity. A system of shelves or racks 510 support the folded noise absorbing apparatus panels 400 in the container 500 . The container 500 has doors 520 that can be opened to access its interior as known in the art. The panels 400 can be retracted using a translation device, forklift or other material handling device. In some embodiments, the container 500 has a removable top or roof. Once the top or roof is removed, upper panels 400 can be lifted out (e.g., with a crane).
FIG. 7A and FIG. 7B illustrate another exemplary noise absorbing apparatus or unit 60 that can be used in the present context. FIG. 7A shows the apparatus 600 A in its stowed or folded configuration. The apparatus 600 A includes a frame 605 having a first support arm 620 and a second support arm 630 . The first and second support arms 620 , 630 can pivot with respect to one another on a hinge 640 similar to scissors. The first support arm 620 includes first upper support members 622 , 624 and first lower support members 626 , 628 . The second support arm 630 includes second upper support members 632 , 634 and second lower support members 636 , 638 . As illustrated, upper and lower angled members 642 , 644 on the first support arm 620 integrally connect the first upper support members 622 , 624 and the first lower support members 626 , 628 , respectively. The angled members 642 , 644 are configured to provide a more compact arrangement of the first and second support arms 620 , 630 . With the angled members 642 , 644 , the first upper support members 622 , 624 are generally parallel to the second upper support members 632 , 634 in the stowed or folded configuration. Similarly, with the angled members 642 , 644 , the first lower support members 626 , 628 are generally parallel to the second lower support members 636 , 638 in the stowed or folded configuration. This configuration is similar to scissors when they are closed shut.
A plurality of resonators 610 (e.g., inflatable bladders or tubes or inverted cup resonators) can be supported by the first and second support arms 620 , 630 . FIG. 7B illustrates the apparatus 600 B in its opened configuration, similar to scissors when they are wide open. When opened as in FIG. 7B the apparatus 600 B is still not in its fully extended (deployed) configuration. Support line 650 can be used to carry the apparatus, and deployment lines 660 can permit the apparatus to be fully deployed and retracted. The first upper support members 622 , 624 and/or the second upper support member 632 , 634 can include a flotation material such as a foam or syntactic foam that causes the upper support members to float above the lower support members.
FIG. 8 illustrates the noise reduction apparatus 80 of the previous drawings in a fully deployed configuration 800 . Upper support arms 602 , 604 are above the lower support arms 606 , 608 . The resonators 610 are coupled to riggings, flexible lines, fabric, or similar flexible support members 820 , which extend from the upper support arms 602 , 604 to the lower support arms 606 , 608 . The support members 820 can define rows and/or columns of resonators 610 in the apparatus 80 .
FIG. 9 illustrates storage and transportation of the noise reduction apparatus of FIGS. 7A, 7B, and 8 . Once stowed and collapsed in its vertical dimension, the scissor-like arms are also collapsed to that configuration of FIG. 7A . Then, a plurality of such units 60 can be stowed on racks, rails or hooks in a shipping container 800 .
FIGS. 10A-C illustrate another embodiment of the present deployable noise reduction apparatus 90 . In FIG. 10A , the apparatus 90 is shown in an open/deployed configuration 900 . The upper portion 902 and lower portion 904 of the apparatus are shown in detail at FIGS. 10B and 10C , respectively. In this arrangement, a separate winch is not required to collapse the apparatus 90 . Instead, the act of lowering the apparatus 90 into the water will cause it to deploy under the force of gravity, and the act of drawing the apparatus 90 up out of the water will cause the apparatus 90 to fold upon itself to a compact folded or collapsed configuration 92 (as illustrated in FIG. 11 ). Deployment lines 910 connect the upper portion 902 to the lower portion 904 to allow the expansion and collapsing of the apparatus 90 similar to a venetian blind. The deployment lines 910 can be connected to a winch, so the same deployment lines can be used to raise/lower the apparatus 90 and to “open” the venetian blinds. Thus, a single winch or deployment cable system can be used on this embodiment.
A support member 920 is disposed across each row 930 . The support member 920 includes a frame 925 for supporting resonators 940 . In some embodiments, the frame 925 is rigid or semi-rigid (e.g., a plastic, rubber, or metallic material). Vertical lines 915 connect the support members 920 to upper and lower cross members 950 , 960 .
FIG. 11 illustrates the collapsed noise reduction apparatus 92 as it would look before it is deployed, for example on the deck of a ship or in the storage holds. In the collapsed configuration, the vertical lines 915 are flexed so the rows 930 are collapsed on to each other. This is similar to a venetian blind when it is opened to expose a window. The apparatus 92 includes a telescoping side support member 940 , as described above.
FIGS. 12A and 12B illustrate two exemplary views of noise reduction apparatuses 94 A, 94 B, respectively, in its deployed or extended configuration. Note that a variety of types of resonators 942 , 944 can be employed in such a system without loss of generality. The apparatuses 94 A, 94 B generally correspond to the apparatus 92 of FIG. 11 .
FIGS. 13A and 13B illustrate two views of self-stowing noise reduction apparatus 96 . In FIG. 13A the apparatus is in its collapsed or stowed configuration (e.g., before or after deployment into a water body or tank 1300 ). In FIG. 13B the apparatus is in its extended or deployed configuration (e.g., while in use in the water).
FIGS. 14A and 14B illustrate an embodiment of a deployable noise reduction apparatus 1400 . The apparatus includes a three-dimensional array of resonators 1410 arranged in the x, y, and z directions. For example, the resonators 1410 are disposed in columns 1420 and rows 1430 . The rows 1430 have a width and a depth in the x and y directions, respectively, which define a plane. The apparatus 1400 is illustrated in a deployed configuration 1425 in FIG. 14A and a collapsed or storage configuration 1475 in FIG. 14B . By adding a third dimension to the array of resonators 1410 , a greater number of resonators 1410 can be deployed on a panel 1450 and, thus, a greater noise absorption can be accomplished by the apparatus 1400 .
FIGS. 15A and 15B illustrate a noise reduction system 1500 formed of four noise reduction panels 1510 . Each panel 1510 is suspended from a frame 1520 . The frame 1520 includes overhangs 1530 for hanging the frame 1520 on a pile gripper 1540 , which is attached to a pylon or a pile (e.g., a pile driving steel pipe) 1550 or other support structure. For efficiency, the term pylon is used in this and other paragraphs to refer to such structures. The pylon 1550 can be a portion of an offshore wind turbine foundation or similar apparatus. The frame 1520 including the panels 1510 can be placed on the pile gripper 1540 with a crane or similar machine.
One or more winches 1560 are connected to the panels 1510 to raise/lower the system 1500 from a collapsed or storage configuration, as illustrated in FIG. 15A , to a deployed configuration 1500 ′, as illustrated in FIG. 15B . Each panel 1510 can raise/lower like a venetian blind, as discussed above. In some embodiments, a single winch 1560 is used to raise/lower the system 1500 so that the panels 1510 are raised/lowered at the same time. Alternatively, multiple winches 1560 can be used and they can be synchronized with a central control system.
FIGS. 16A-D illustrate a deployable noise reduction apparatus 1600 comprising four noise reduction panels 1610 mounted on an annular articulating stowable frame 1620 . In some embodiments, the noise reduction panels 1610 are rigidly and/or securely mounted on the annular frame 1620 . The annular frame 1620 is connected to a secondary frame 1630 , which can be mounted on a ship. The annular frame 1620 can pivot vertically from a lowered position ( FIG. 15A ) to a raised position ( FIG. 15B ). In addition or in the alternative, the annular frame 1620 can pivot horizontally. The rigid and/or secure mounting of the panels 1610 on the annular frame 1620 allows the annular frame 1620 to pivot while the panels 1610 are mounted on the annular frame 1620 . As illustrated in FIG. 15C , a first arm 1640 and a second arm 1650 of the annular frame 1620 can open like a claw to receive a pylon 1660 or other support structure inside the annular frame 1620 . After the pylon 1660 is inside the annular frame 1620 , the first and second arms 1640 , 1650 can close to mount the annular frame 1620 on the pylon 1660 . The noise reduction panels 1610 are then lowered into a deployed configuration 1600 ′ ( FIG. 15D ) as discussed above. The noise reduction apparatus 1600 provides an efficient structure for reducing noise proximal to a jackup rig or other vessel that includes a pylon.
FIGS. 17A-E illustrate a deployable noise reduction apparatus 1700 comprising noise reduction panels 1710 mounted on an annular articulating stowable frame 1720 . As illustrated in FIG. 17A , the panels 1710 include a line 1730 for releasably hanging (e.g., by using a crane) the panels 1720 on brackets 1740 connected to the annular frame 1720 . The apparatus 1700 allows the system to be customized in the field by interchanging the panels 1710 to select those best suited for a given application. The annular frame 1720 is connected to a secondary frame 1740 , which can be mounted on a ship. In some embodiments, the panels 1710 are mounted on the annular frame 1720 after the annular frame 1720 has pivoted down to a deployed orientation as illustrated in FIGS. 17A-E . As illustrated in FIG. 17C , a first arm 1740 and a second arm 1750 of the annular frame 1720 can open like a claw to grip/receive a pylon 1760 or other support structure inside the annular frame 1720 . After the pylon 1760 is inside the annular frame 1720 , the first and second arms 1740 , 1750 can close to mount the annular frame 1720 on the pylon 1760 ( FIG. 17D ). The noise reduction panels 710 are then lowered into a deployed configuration 1700 ′ ( FIG. 17E ) as discussed above. The noise reduction apparatus 1700 provides an efficient and customizable structure for reducing noise proximal to a jackup rig or other vessel that includes a pylon.
FIG. 18 illustrates an embodiment of a deployable noise reduction apparatus 1800 . The apparatus 1800 includes a noise reduction panel 1810 mounted on an interior wall 1820 of a protective frame/enclosure 1830 . The protective frame/enclosure 1830 surrounds the panel 1810 while the panel 1810 is in a folded or storage configuration as illustrated in FIG. 18 . To deploy the apparatus 1800 , a second wall 1825 is removed (e.g., opened or physically removed) so that the panel 1810 can be lowered to an unfolded or deployed configuration as discussed above. The protective frame/enclosure 1830 can protect the panel 1810 from damage during transportation. In addition or in the alternative, the protective frame/enclosure 1830 can provide a regular shape for transporting the apparatus 1800 , for example, in a shipping container intermixed with other goods. The protective frame/enclosure 1830 can be made out of a plastic, corrosion-resistant metal, or similar material. In some embodiments, the protective frame/enclosure 1830 is a shipping container and the second wall 1825 is a removable and/or openable wall of the shipping container. For example, the noise reduction panel 1810 can be attached (e.g., semi-permanently or permanently attached) to the interior wall 1820 of the top of the shipping container and the bottom is openable and/or removable so that the noise reduction panel 1810 can be deployed.
Those skilled in the art will appreciate upon review of the present disclosure that the ideas presented herein can be generalized, or particularized to a given application at hand. As such, this disclosure is not intended to be limited to the exemplary embodiments described, which are given for the purpose of illustration. Many other similar and equivalent embodiments and extensions of these ideas are also comprehended hereby.
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A deployable underwater noise abatement system allowing packing and deploying an organized set of grouped resonators is disclosed. The system allows relatively compact storage and transportation of the noise abatement apparatus when not in use, then, when deployed, the apparatus can be lowered into the water and extended.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a method for feeding a yarn to a textile machine for its processing and its arrangement for subsequent use. The invention also relates to a textile machine of the aforestated type in which said method is implemented.
2. Description of the Related Art
A textile machine of the aforesaid type, such as a texturizing-interlacing, interlacing or doubling machine, is known to operate on a yarn comprising at least two threads which are secured together (for example interlaced) in order to be collected on a support (a bobbin or spool) for subsequent use in producing an article in a corresponding different textile machine.
Such known textile machines for transforming textile fibres or yarns combine several identical or different textile fibres or yarns in order to transform the group of fibres or yarns into a yarn or fibre having characteristics which are a combination of the characteristics of each fibre or yarn combined in this manner.
In such machines the production process is normally very lengthy, varying from 30 minutes to more than 60 minutes, depending on the counts processed and on the dimensions of the yarn spool or bobbin produced. The process is also normally highly automated, using autodoffing of the spool produced.
In many of these machines, and in particular in machines for interlacing or texturizing and interlacing a synthetic fibre or thread such as nylon or polyurethane with an elastomeric fibre or thread, this latter is fed to the machine processing region by the so-called Deruile' method, i.e. by unwinding and feeding the yarn from its rotating support bobbin at a speed synchronized with the rate at which the processed yarn is collected on said spool or bobbin. In other words, the bobbin supporting the elastomeric thread rotates about its axis at a speed synchronized with the rotational speed of the bobbin or spool on which the yarn is collected after its processing, said synchronized speed enabling the elastomeric thread to be fed to the machine production region at a constant tension determined on the basis of requirements.
Consequently the ratio of collection speed to elastomer feed speed determines the tension or extension of this latter.
This yarn feeding method presents many limitations related to the modality of continuing yarn feed when the elastomeric thread bobbin runs out. For example, in such machines it is not possible to use the known so-called “head-tail” technique, which when a yarn bobbin has run out enables the production process to continue without interruption because of the presence of a second bobbin, the head of which (i.e. the commencement of the thread supported by it) is linked or rather knotted to the tail of the first (i.e. to the end of the thread supported thereby); the reason for this impossibility is that the threads of these bobbins cannot be knotted together because one of them rotates.
Changing the thread bobbin automatically is extremely complex, costly and limited because when a first bobbin of elastomeric thread runs out it is evidently not possible to automatically start the second at full speed.
Moreover if the elastomeric thread breaks in proximity to its end on the relative bobbin, to prevent its further rapid breakage (with consequent further halting of the textile machine) it is preferred to discard the depleting bobbin for a new bobbin; this evidently results in high costs caused by production discards.
In any event, the known method of feeding the textile machine with the elastomeric thread while maintaining its tension constant by controlling the rotation of the corresponding bobbin never allows complete depletion of the bobbin, with consequent creation of rejects (with their associated costs). This is because the initial layers wound on the preparation bobbin causes it to break the thread on the next before its complete depletion.
For this reason, “Derule'” feed devices require the presence of sensors for monitoring yarn breakage and sensors for indicating the bobbin end. In addition, as a textile machine of the stated type comprises numerous parts (“heads”), each for automatically producing a processed yarn, the number of such “heads” assigned to an operator is very high resulting, in the case of yarn breakage, in prolonged intervention downtimes which can heavily affect final production efficiency levels.
SUMMARY OF THE INVENTION
An object of the present invention is to provide, for processing a yarn, a method and textile machine which are improved compared with the methods and machines of the state of the art.
A particular object of the invention is to provide a method for feeding at least one elastomeric thread to a textile machine of the stated type which overcomes the problems of analogous known methods.
Another object of the present invention is to provide a method which, by means of a new mode for feeding the elastomeric thread, enables the bobbin of this thread to be automatically replaced without halting the textile machine production cycle.
A particular object of the invention is to provide a method of the stated type which enables the automatic yarn change technique known as “head-tail” to be also used in a textile machine of the stated type.
Alternatively, another object of the invention is to provide a method enabling two feed bobbins to automatically be changed over if the elastomeric thread of one of them breaks, or if one of these bobbins runs out, or if the “head-tail” technique is unsuccessful due for example to a badly made knot connecting the “tail” of the depleting thread to the “head” of the new elastomeric thread.
Another object is to provide a method which does not slow down the production process underway, while maintaining efficiency, quality and production at the highest possible levels, substantially equal to 100%.
Another object is to develop a yarn processing method and textile machine of very simple and economical implementation and construction.
A further object is to provide a method which automatically identifies a “tension error”, i.e. a situation in which the thread is broken or lacking, or the processed yarn is outside predefined quality limits due for example to mistaken location of the yarn bobbin.
Another object is to provide a method allowing the use of elastomeric thread bobbins of not necessarily standard dimensions, including considerable dimensions, so reducing the number of thread jointing points, and which can be used either by adding it to new generation machines or by updating machines already in client use.
Finally, another object is to provide a method the implementation of which does not require the use of complex synchronizations and mechanical and electronic interfaces within the textile machine, but which instead can be implemented without necessarily having to exchange data or synchronizations with the textile machine.
These and further objects which will be apparent to the expert of the art are attained by a yarn processing method and machine in accordance with the accompanying claims.
BRIEF DESCRIPTION OF THE DRAWING FIGURES
The present invention will be more apparent from the accompanying drawings, which are provided by way of non-limiting example and in which:
FIG. 1 is a block diagram showing a first embodiment of the method of the invention used for automatically replacing a bobbin of elastomeric thread, either because it is empty or because of thread breakage;
FIG. 2 is a block diagram showing a second embodiment of the method of the invention used for complete automatic replacement of the empty elastomeric thread bobbin using the “head-tail” bobbin change technique; and
FIG. 3 is a block diagram showing a third embodiment of the method of the invention using an air-operated double interlacer for automatically changing elastomeric thread feed from one bobbin to another.
In the figures, corresponding parts are indicated by the same reference numerals.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
With reference to FIG. 1 , this shows a textile machine T of the type for processing a yarn and for arranging it on spools or bobbins for its future use in a different textile machine for forming a finished article (for example an item of underwear). The machine T can be an interlacing machine, a texturizing-interlacing machine, or a doubling machine, all known per se.
The machine T presents a yarn processing part T 1 . This latter operates on a yarn 2 formed by combining, binding or assembling together two threads 3 and 4 . For example, the thread 3 is a nylon thread originating from a known feed and drafting device or from a usual yarn bobbin (neither shown here).
The second thread 4 is of elastomeric material; this thread originates from a known constant tension yarn feed device 5 which feeds said thread 4 at a predetermined tension, preferably and advantageously programmable on the basis of the count of the elastomeric thread used and/or of the desired process, said thread originating from a bobbin 6 . As stated, the device 5 is known per se: for example such a device can be that described in EP950742 or in U.S. Pat. No. 5,566,574, and is such as to enable the thread 4 to be fed at least at constant tension (and preferably at constant tension and constant rate) equal to a predefined (and advantageously programmable) value. This device is necessary for correct operation of the machine T as the thread 4 unwinds from the bobbin 6 by simple free withdrawal or unwinding, and hence without possessing any predefined tension.
This characteristic of the invention is in contrast to the normal mode of feeding elastomeric thread in a textile machine for yarn processing such as that described, even though machines of this type (for example an interlacing machine) have been available commercially for many decades and even though devices for regulating the tension of a thread fed to a textile machine have also been known for decades in their simplest form. Consequently the present invention is directed towards a chosen technique contrasting that used up to the present time in constructing yarn processing machines of the described type. As described hereinafter, the present invention enables advantages and applications to be obtained which are unattainable by similar textile machines of the state of the art operating by known methods.
The thread 4 originating from the device 5 is combined with the thread 3 to obtain a yarn 2 by inserting these threads into a known combining device (for example an interlacing member) indicated by 7 .
According to another characteristic of the invention, as the thread 4 unwinds freely from the bobbin 6 by simple withdrawal therefrom (i.e. by the Defile' method), the thread 4 can be automatically replaced, if the bobbin 6 is about to empty, by another thread 4 A originating from another bobbin 6 A totally identical with the said bobbin 6 . This thread 4 A unwinds freely from the bobbin 6 A after which it cooperates with a device 5 A for adjusting its tension, this being entirely equivalent to or identical with the said device 5 .
The thread 4 is replaced by the thread 4 A where the threads 4 and 4 A enter the combining device 7 , by a known change-over device 10 such as a usual thread change-over device similar to that used in knitting, hosiery or weaving machines, or a known air operated interlacing machine or the like. The change-over device 10 can be mechanical, pneumatic, electromagnetic, etc. Its operation is controlled by a control unit 11 to which at least the said devices 5 and 5 A are connected; this unit can be part of the device 10 .
It will now be assumed that the thread 4 fed by the device 5 from the bobbin 6 is interrupted at the entry or exit of the device 5 by a defect in the thread or because the thread has run out on the bobbin.
In that case the device 5 generates an error signal to immediately note this situation (for example, if the device 5 is of the type described in U.S. Pat. No. 5,566,574, it generates a “Tension Error” signal), this signal being fed to the unit 11 . The device 5 consequently generates an alarm signal which is used by the unit 11 to activate the thread change-over device 10 which operates immediately on the thread 4 A instead of on the preceding thread 4 . In this manner the part 1 A of the machine 1 can continue the yarn processing without any interruption.
In the meantime, the operator in charge of the machine has all the time necessary to note the abnormality and to change the now empty bobbin 6 or repair the thread 4 which was interrupted. In either case the thread 4 is again connected (in known manner) to the device 5 and the thread 4 again associated with the change-over device 10 to enable this latter to again effect a change-over when the thread 4 A runs out or breaks.
Each time a change-over is signalled, a request can be fed to the operator to intervene and a signal be fed to the textile machine indicating that thread change-over has taken place, in order if necessary to mark the yarn bobbins produced if this production is to be classified as second choice.
If a double indication of thread change-over takes place originating from both the devices 5 and 5 A and fed to the unit 11 , an alarm signal can be generated to halt the process on the textile machine T, as production is impossible without both the threads 4 and 4 A.
This solution evidently enables potentially perpetual production to take place in spite of any breakages or run-outs of the threads 4 or 4 A from the bobbins 6 and 6 A respectively, hence ensuring a production efficiency close or equal to 100%.
In contrast, FIG. 2 shows a solution operating as described for FIG. 1 , but using pairs of thread bobbins 6 and 60 together with 6 A and 60 A, enabling thread bobbin change-over to take place by the “Head-Tail” method without giving rise to any process defect which may have been caused by the time, even though short, required for thread replacement by the device 10 (in this respect it must be considered that processing may take place at very high speeds), to hence produce only first choice yarn even if the thread has to be changed over. Hence in the case of thread breakage, change-over between the thread 4 and the thread 4 A is done by the device 10 .
FIG. 3 shows a further solution operated in the same manner as the solution of FIG. 1 , but with the difference that the thread change-over device 10 is replaced by two combining devices 7 A, 7 B (for example, usual known air-operated interlacing devices). Said devices 7 A and 7 B are activated by the feed device 5 A in the case of breakage or run-out of the thread 4 A and by the feed device 5 in the case of breakage of the thread 4 . When one of said devices 7 A and 7 B is not in operation, it allows each thread present at its entry to pass without acting on it and simply operates as a thread guide.
Because of the particular manner of unwinding each elastomeric thread from its respective bobbin and the fact that the regulation of its feed tension to the processing part of the textile machine is independent of parameters related to the collection of the processed yarn, the textile machine can be simplified in its construction and in its operation control part. Elastomeric thread bobbins of any size can be used, as there are no restrictions relating to the manner of supporting the bobbin, such restrictions however existing in known machines because of the fact that in these latter the thread tension is controlled by controlling the rotation of the bobbin on its own support shaft.
Moreover, because of the particular manner of unwinding said thread, the invention enables the elastomeric thread used in the process to be replaced by another thread when the former breaks or runs out on its corresponding bobbin. This enables textile machine operation to be maintained for a considerable time independently of the quantity of elastomeric thread present on the respective bobbin.
Numerous embodiments of the invention can be obtained in the light of the aforegoing description by suitably choosing the aforedescribed devices, while still implementing a method and achieving a textile machine in accordance with the ensuing claims.
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A method for feeding a yarn to a textile machine for its processing and preparation for subsequent use, such as an interlacing, texturizing-interlacing or doubling machine, the yarn including at least two threads ( 3, 4 ) which are bound together, the first thread ( 4 ) and second thread ( 3 ) unwinding from a corresponding bobbin, the first ( 4 ) of said threads ( 3, 4 ) being an elastomeric thread. This latter is unwound from the relative bobbin ( 6 ) by withdrawal under free tension, said elastomeric thread ( 4 ) then being subjected to tension regulation in order to feed it at constant tension to the next stage, in which it is bound to the other thread.
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BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] This invention relates to a method for removing sediments, fouling agents, and the like, from ducts and tanks and to apparatus adapted for use in said method.
[0003] 2. Description of the Related Art
[0004] Build-up of debris or fouling agents in ducts and/or tanks carrying or containing impure or otherwise sediment-generating liquids represents a common problem in many technological areas.
[0005] One of the fields most affected by this problem is ship-building, and particularly medium-high class pleasure boating. Inboard engines are provided with a seawater cooling systems wherein seawater is pumped up and subsequently discharged; seawater contains various micro-organisms of both animal and plant origin, which exhibit a tendency to establish and proliferate in cooling system ducts. This kind of sediments causes remarkable problems and damage to engine assemblies and has a high economic impact. The problem of sediment buildup can be solved by the use of washings with sodium hypochlorite solutions or other oxidizing agents capable of attacking such microorganisms. Of course, these chemical substances are environmental pollutants and their use is encountering more and more limitations.
SUMMARY OF THE INVENTION
[0006] Accordingly, one aim of the present invention is to provide a method for removing sediments, fouling agents and the like from liquid ducts and/or tanks without using aggressive systems that can damage both the structure to be restored and the surrounding environment.
[0007] Another aim of the present invention is to provide an apparatus for carrying out a method for removing sediments, fouling agents and the like from liquid ducts and/or tanks without using aggressive systems that can damage both the structure to be restored and the surrounding environment, said apparatus being simply made and easily applied to various kinds of structures affected by similar problems due to sediments and fouling.
[0008] Thus, one object of the present invention is a method for removing sediments, fouling agents and the like from fluid, in particular liquid, ducts and/or tanks, characterized in that said method comprises applying ultrasound vibrations to a plurality of points of the structure, such as a duct or tank to be treated, said ultrasound vibration being continuously applied outside the structure at a given frequency and power.
[0009] Another object of the present invention is an apparatus for applying ultrasounds to a structure, such as a duct, tank or the like, comprising suitably-powered ultrasound generating means, transducer means for the ultrasounds generated from said ultrasound generating means, said transducer means being connected to said ultrasound generating means through connecting means and being coupled to said structure through suitable coupling elements.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] Other advantages and features of the present invention will be apparent from the following description of an embodiment thereof, which is provided by way of illustration, and not by way of limitation, with reference to the accompanying drawings, wherein:
[0011] FIG. 1 is a schematic representation of an embodiment of the apparatus according to the present invention; and
[0012] FIG. 2 is a detail of FIG. 1 showing a cross-section of a transducer assembly coupled to a duct.
DETAILED DESCRIPTION OF THE INVENTION
[0013] FIG. 1 illustrates an embodiment of an apparatus for carrying out the method according to the present invention; reference numeral 1 denotes an ultrasound generating unit which is connected, through a plurality of wires 101 , to a plurality of transducer assemblies 2 which are coupled to a duct 3 through coupling elements 103 .
[0014] FIG. 2 shows a detail of one transducer assembly 2 coupled to the duct 3 . The transducer assembly 2 comprises a substantially bell-shaped box-like body 102 whose open end is provided with a radially-projecting flange 132 for securing the body 102 to a plate 162 through screws 142 . A transducer 202 is attached to the plate 162 through an adhesive resin layer 212 , said transducer 202 being connected, through wires 141 , to connectors 121 fitted in an insert 122 which engages the opening of a tube piece 112 at the bottom of the body 102 of the assembly 2 . A cap 131 is mounted to the tube piece 112 , and this cap houses connectors 111 for connecting wires 101 from the ultrasound generating unit 1 to the transducer assembly 2 (see FIG. 1 ). The plate 162 is axially provided with a threaded pin 172 which is coupled to a threaded sleeve 103 welded to the outer wall of said duct 3 through a welding seam 113 ; an annular sealing element 152 is provided between the plate 162 and the flange 142 of the body 102 .
[0015] The method and apparatus for removing sediments, fouling agents and the like according to the present invention are further explained in the following. Taking the duct 3 as an example of a cooling duct for an inboard propulsion engine of a boat, build-up of fouling mainly due to microbiological components in seawater (phytoplankton, zooplankton) is a known problem; according to the method of the invention, this build-up can be prevented by continuously applying ultrasounds at a frequency in the range of 10 to 40 kHz, preferably in the range of 17 to 26 kHz, to the duct 3 . The frequency of the applied vibration mainly depends on the wall thickness of the structure to be treated; generally, the larger the wall thickness, the higher the frequency of the applied vibrations. The power used is usually in the range of 300 Watts to 2 kilowatts, and preferably in the range of 600 Watts to 1,000 Watts. The application to this type of duct is only one among different examples of application for the method and apparatus according to the present invention, which can actually be used whenever a build-up of sediments and/or fouling agents exists in structures which contain and/or carry fluids.
[0016] The continuous application of ultrasound inhibits the formation of build-ups on the wall of the ducts and prevents the formation of fouling that can cause malfunctions in the cooling system. In this case, the main problem to be solved is how ultrasounds can be applied to the structure to be treated. In fact, it is necessary that vibration impacting the structure itself, e.g., a duct, is as smooth as possible, while avoiding that transducer means hinder the flow within the structure and that the morphology of the structure is dramatically modified. Furthermore, because of the substantially circular cross-section of a duct, it is necessary that vibration is effectively and completely transferred to the highest degree without substantially changing the structure of transducers. To achieve these results, the unique transducer is fitted into a transducer assembly of suitable construction such as to be coupled with the structure to be treated in a very simple way, said structure having in turn been modified to a very small extent. In order to install the transducer assembly in a stable and perfectly functional way according to the invention, a threaded sleeve is welded to the external surface of the duct.
[0017] The transducer itself is housed in a substantially sealed container body 102 , and it is attached to a face of a plate through a suitable adhesive such as an epoxy resin, a polystyrene resin or the like, said plate being coupled to the sleeve which is welded to the duct. In this way, vibration is transferred to the duct, and this type of connecting system is well suited for structures greatly varying in shape and size, so as to allow for a wide use of the method and apparatus according to the present invention.
[0018] Advantageously, the transducer assembly 2 is connected to wires 101 through connecting means 111 , 121 which enable its complete removal and replacement. Moreover, the insert 122 in the tube piece 112 , along with the cap 131 , further assure sealing within the transducer assembly 2 and prevent wear thereof due to the action of external agents.
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Taught herein are a method and apparatus for removing sediments, fouling agents and the like from fluid, in particular liquid, ducts and/or tanks, characterized in that the method comprises applying an ultrasound vibration to a plurality of points of the structure, duct or tank to be treated, said ultrasound vibration being continuously applied outside the structure at a given frequency and power.
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BACKGROUND OF THE INVENTION
The present invention relates to a device for connecting, on the one hand, a lifting cord of a device for lifting one or more warp threads on a weaving machine and, on the other, at least one harness cord which is provided for lifting a warp thread, comprising a first and a second coupling element which are connected to the lifting cord and to the abovementioned harness cord respectively, and which can be coupled and uncoupled.
A fabric consists essentially of warp threads and weft threads, and is formed on a weaving machine by each time forming a shed between the various warp threads, and inserting a weft thread through said shed. Before each insertion of the weft thread, certain warp threads are lifted to a well-defined height, at the point where the weft thread is to be inserted, by a device for lifting the warp threads, in order to form the desired shed. The positions of the various warp threads are determined relative to the successive weft threads depending on a fabric to be produced. The positioning of the warp threads is generally carried out by means of lifting cords, which are connected to harness cords by means of a detachable connecting device, while each harness cord is provided for lifting a warp thread (for example, by means of a heald which is connected to the harness cord and has a heald eye, through which the warp thread extends). Several harness cords can be connected to the same lifting cord if each of the warp threads connected to said harness cords has to assume the same position each time during the weaving.
Devices of the type described in the first paragraph of this description are known from European Patent Application No. 0,546,967 and from German Patent No. 4,213,958.
The device described in this European patent application comprises a first coupling element, which is connected to the lifting cord and consists of two flank pieces which are connected to each other by means of a crosspiece. A second coupling element, which is connected to several harness cords, is in the form of a clip, the two upward directed arms of which end in a hook shape. The hook-shaped parts face each other, and the arms are elastically deformable. By pushing the arms away from each other, the crosspiece can be placed in the space between the arms, below the hook-shaped parts. When the arms are sprung back to their original positions, they enclose the crosspiece, and the hook-shaped parts rest on the top surface of the crosspiece. The two coupling elements are connected to each other in this way, and they can no longer be uncoupled as the result of an axial pulling force. Indeed, for uncoupling the coupling elements, two flanks of the second coupling element, which are connected to the arms, have to be forced towards each other, in order to move the arms away from each other until the crosspiece can pass between the hook-shaped parts, in order to leave the space between the arms.
In the case of the device described in the abovementioned German patent the first coupling element comprises a sleeve, and the second coupling element comprises two upward directed, elastically deformable arms situated opposite each other. The arms are formed in such a way that they each form a supporting edge at the sides facing away from each other. For the coupling of the two coupling elements, the arms are inserted through an opening into the sleeve. The arms are forced towards each other by the inside walls of the sleeve. A widened part is also provided inside the sleeve, by means of which an inside edge is formed in the sleeve. The arms can spring back from each other in this widened part, with the result that their supporting edges ultimately rest above the inside edge of the sleeve. Due to the fact that the supporting edges of the arms knock against the inside edge of the sleeve, the second coupling element can no longer leave the sleeve as the result of an axial pulling force.
For the uncoupling thereof, the arms actually have to be forced towards each other in the radial direction, in order to be able to make them leave the sleeve through the opening.
In the case of the devices of the prior art described above, the coupling elements cannot become detached from each other under the influence an axial pulling force exerted thereon without damage occurring.
During weaving it can happen that, as the result of a knot becoming caught up or several warp threads becoming entangled, a warp thread becomes so taut that a normal lift of the warp thread becomes impossible.
However, the device for lifting the warp threads continues working, in order to lift the warp thread. This results in breakage of the warp thread, or a part of the device for lifting the warp thread, or a part lying in between which has been provided to transmit the lifting movement to the warp thread.
In the case of a jacquard machine, which interacts with tackle elements for achieving the lift, either the warp thread or the weakest part of the following parts will break: the jacquard machine hook, the tackle element, the tackle cord, the harness hook, the harness cord, or the jacquard heald. In particular, if relatively strong warp threads are being used in the weaving, parts will be damaged when a warp thread becomes caught up.
In the case of electronically controlled jacquard machines one of the following parts can break: the suspension element of the hook, the hook itself, the tackle element, the tackle cord, or the jacquard hook of the tackle cord.
In each case expensive parts have to be replaced. These replacements are also very time-consuming.
SUMMARY OF THE INVENTION
The object of this invention is to overcome this disadvantage. This object is achieved by providing a device for connecting, on the one hand, a lifting cord of a device for lifting one or more warp threads on a weaving machine and, on the other, at least one harness cord which is provided for lifting a warp thread; comprising a first and a second coupling element, which are connected to the lifting cord and to the above-mentioned harness cord respectively, and which can be coupled and uncoupled, while the device comprises an intermediate element which can be connected to the respective coupling elements for coupling of the coupling elements, and while the connection of at least one coupling element to the intermediate element is provided so that it can be broken as the result of a pulling force exerted thereon, in order to prevent damage through overloading.
When a certain pulling force (indicating overloading) is reached in the harness cord and the lifting cord, the coupling elements will uncouple, and the connection will be broken before the warp thread or one of the parts connected thereto breaks.
The device according to this invention is a mechanical protective element. When the coupling elements and the intermediate elements are being manufactured, the shape and the dimension are determined with such great accuracy that the coupling elements uncouple when a predetermined pulling force is reached. This force is sufficient in this case to ensure normal operation of the weaving machine, and is smaller than the force at which one of the abovementioned parts or a warp thread would break.
After the removal of the cause of the overloading pulling force, the coupling elements can be recoupled.
The coupling can also be carried out very easily and quickly, which--inter alia--saves a great amount of time during the connection of a large number of lifting cords and harness cords when a weaving machine is being made ready for operation.
Using an intermediate element give the advantage that one of the coupling elements or both coupling elements can be made of limited transverse dimension, so that they can be passed easily through openings or between parts of the weaving machine.
The transverse dimension of the first coupling element are preferably relatively small, because it is this element which generally has to be passed through narrow openings (e.g. a bore in a grate of the weaving machine and a slit in a tackle element) when the lifting cord is being fitted or replaced. (A tackle cord is subject to fairly great wear, owing to the fact that it is constantly rolling to and fro over a rolling element of a tackle element, with the result that it has to be replaced regularly).
The intermediate element and the second coupling element are in this case preferably provided so that they uncouple as the result of a certain pulling force exerted thereon, in order to prevent damage through overloading, while the intermediate element and the first coupling element are provided so that they remain coupled under the influence of the abovementioned pulling force.
Due to the limited transverse dimensions of the first coupling element, this embodiment is the most readily practicable one.
The device according to the invention is particularly user-friendly if the coupling elements can be coupled and uncoupled by hand. Besides, the coupling or uncoupling can be carried out very quickly in this way.
In a particularly advantageous way, the coupling elements are provided in such a way that in the coupled state they are rotatable relative to each other about an axis running virtually in the direction in which the lifting cord and the harness cord extend in the arrangement on a weaving machine.
The harness cord can consequently exert no rotation effect whatsoever on the lifting cord (e.g. tackle cord) or the parts connected thereto (e.g. jacquard selection hook). After their suspension on a weaving machine, the harness cord and the lifting cord will thus assume their free length, without twisting in the respective cords.
When the connections are being made between lifting cords and harness cords on a weaving machine, the lifting cords and the harness cords have to be passed through openings in a bottom board and/or grate.
According to a preferred embodiment of this invention designing the first and/or the second coupling element in such a way that it (they) can be pushed through an opening in a bottom board and/or grate, the connection between lifting cords and harness cords can be made easily and quickly without any removal of parts.
When a tackle element is provided for achieving the lift of a warp thread connected to the harness cord, it is also particularly advantageous if the first coupling element connected to the tackle cord can be pushed through the slit of the tackle element.
The connection between lifting cord and harness cord(s) can then be made without removal of the tackle element.
According to another preferred embodiment of the device according to this invention, the first and/or the second coupling element are provided with a transverse opening in the element.
This makes it possible to provide the various first coupling elements on a first carrying element, and/or the various second coupling elements on a second carrying element. The carrying elements extend, or are provided with parts which extend, through the above-mentioned transverse openings of the coupling elements provided thereon.
By providing the various coupling elements on a carrying element, it is ensured that they can be presented together--on their carrying element--for their connection to intermediate elements and/or to the other coupling elements provided on a carrying element or otherwise.
The method described above for achieving a connection between several lifting cords and harness cords on a weaving machine constitutes another object of this invention.
In the case of the known methods for achieving the several connections mentioned above, all connections are carried out manually one by one. This work is thus very time-consuming, particularly since a large number of connections generally have to be made on a weaving machine.
In the case of the method according to this invention, several connections can be achieved much more quickly through the better presentation of several coupling elements simultaneously.
Moreover, the coupling elements can be provided on their carrying element, in order to prevent the lifting cords and harness cords connected thereto from becoming entangled (for example, while the weaving machine is being transported), and in order to maintain their sequence. This again achieves a saving in time when several connections are being made between lifting cords and harness cords. Besides, this method is suitable for automation.
In a particularly preferred embodiment of the device according to this invention, the first and the second coupling element comprise a pin with a radially projecting head and a stud respectively, while the intermediate element comprises a body which encloses a first and a second channel, which open out by way of respective openings to the outside. The pin with head can extend through the opening in the first channel, while this channel comprises retaining means, in order to prevent axial displacement of the head towards the opening. The body of the intermediate element is provided with a recess, by way of which the pin with head can be placed in or removed again from the channel. The stud can be placed in the axial direction in the second channel, while the stud and the second channel are provided in such a way that the stud is retained in the second channel and can be pulled out of said second channel as the result of a certain pulling force exerted thereon in the axial direction.
According to a most preferred embodiment, the body of the intermediate element is elastically deformable, and the pin is provided with a radially projecting collar. The part of the pin between the collar and the head is the same shape and has the same dimensions as the part of the first channel between the opening and the retaining means, while the part of the recess by way of which the head can be placed in the first channel is situated past the retaining means, over a distance which is smaller than or equal to the length of the collar.
The features of the device according to this invention are clarified further by means of a detailed description of a non-limiting example of an embodiment thereof. In this description reference is made to the appended drawings:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective drawing of the coupling elements and the intermediate element in the uncoupled state.
FIG. 2 is a perspective drawing of the end of the first coupling element and the intermediate element in the uncoupled state.
FIG. 3 is a perspective drawing of the ends of both coupling elements and the intermediate element in the coupled state, in which the body of the intermediate element has been cut away over a quarter of the periphery.
FIG. 4 is a perspective drawing of both coupling elements and the intermediate element in the coupled state, in which the body of the intermediate element has been cut away over a quarter of the periphery.
FIG. 5 is a section in the lengthwise direction of the intermediate element.
FIG. 6 is a perspective drawing of a device which is provided for lifting a warp thread on a weaving machine by way of a set of jacquard machine hooks, a tackle element and a device according to the invention.
FIG. 7 is a detail drawing in perspective of a part of FIG. 6.
FIGS. 8A and 8B are perspective drawings of carrying elements in the form of combs for coupling the device according to the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The first coupling element (2) is connected at one end to a bottom tackle cord (1), which is guided over the bottom roller element of a tackle element (16) of a jacquard machine (see FIGS. 6 and 7).
The bottom tackle cord (1) extends upwards through a bore (23) in a grate (18) and is connected by the other end to said grate (18), which is in a fixed position, or is movable vertically. A top tackle cord (17) is connected by each end to one of two complementary jacquard hooks (14). Each jacquard hook (14) is carried along by means of a knife (15), which moves up and down. Both knives (15) move in counterphase relative to each other.
By making the hooks (14) move along with the knives (15), or by selecting (retaining) one hook or both hooks (14) in a top (or bottom) position, a well-defined lift of a warp thread (21), extending through the heald eye of the jacquard heald (20), is produced by way of the top harness cord (17), the tackle element (16), the bottom tackle cord (1), the harness cord (5) and the jacquard heald (20). The harness cord (5) extends through a bore in a bottom board (19). The tackle element (16) comprises two flank plates (16'), between which the roller elements are rotatable disposed. A slit (22) is provided between the two roller elements--between the flank plates (16')--for passing through the tackle cords (17), (1).
The first coupling element (2) is cylindrical in shape (see FIGS. 1 to 4) and has a relatively small diameter (for example, 3.5 mm), so that this element (2) can be pushed through the bore of the bottom board (19) or grate (18), and through the slit (22) of the tackle element (16). This means that easy replacement of the tackle cord (1) is possible without removal of parts. The other end of the first coupling element (2) is provided with a cylindrical pin (2") extending along the axis of the body, which pin bears a radially projecting cylindrical head (2') on the free end.
The pin (2") has on the base, against the body of the coupling element (2), a radially projecting collar (2'"), the length of which is indicated by (a) in FIGS. 2 and 3.
The first coupling element (2) is provided with an elongated opening (6) which passes through the body.
The second coupling element (4) likewise has an elongated body which is cylindrical in shape, but which can have a larger diameter than that of the first coupling element (2), since it does not have to be pushed through bores or slits of small dimensions. Moreover, owing to this larger diameter, two or more harness cords (5) can be connected to the second coupling element (2).
The one or more harness cords (5) are connected at one end of the body, while the other end is provided with a cylindrical stud (4') projecting along the axis of the body.
The second coupling element (4) is also provided with an elongated opening (7) which passes through the body.
The intermediate element (3) comprises a body (3') with a cylindrical outer shape and encloses internal channels (10, 13) which open to the outside by way of two openings (8), (9), which are provided opposite each other in the ends of the body (3').
This internal space determines from the two openings (8), (9) a first channel (10) and a second channel (13), which are provided for the pin (2") with head (2') and for the stud (4') respectively (see FIG. 5).
The first channel (10) has a cylindrical part of virtually constant diameter running from the opening (8). The diameter and the length of this part correspond to the diameter and the length of the pin (2") of the first coupling element (2).
This part then passes into a cylindrical part of greater, constant diameter, so that an a annular edge (11) is formed in this first channel (10).
The diameter of this part of greater, constant diameter corresponds to the diameter of the head (2'). At the level of this first channel (10) a recess (12) is provided in the body (3') of the intermediate element (3), by means of which recess the pin (2") with head (2') can be pushed into or removed again from the first channel (10). Said recess (12) is provided from the end of the body (3') along the edge of the opening (8) of the first channel (10). From that end, up to a distance (b) past the annular edge (11) in the first channel (10), the recess is slit-shaped, having a width which is a little smaller than the diameter of the pin (2"). The recess (12) also forms a window (12') connecting to the slit-shaped part, and of a width and length corresponding at least to the diameter and the length of the head (2').
The distance (b) is smaller than or equal to the length (a) of the collar (2'").
The second channel (13) has a cylindrically shaped part of virtually constant diameter, running from the opening (9).
This part then passes via a slanting edge into a cylindrical part of greater, constant diameter. This latter part also passes into a cylindrical part of gradually decreasing diameter.
The body (3') of the intermediate element (3) is elastically deformable.
The pin (2") with head (2') can be pressed with the thumb and forefinger by way of the recess (12) into the first channel (10), the head (2') being placed in said channel (10) by way of the window (12'). The walls of the body (3') bend away from each other in the process, since the width of the slit-shaped part of the recess (12) is smaller than the diameter of the pin (2").
Due to the fact that the window (12') by way of which the head (2') is pushed into the first channel (10) is situated over a distance (b) past the annular edge (11), in a first phase of the coupling of the first coupling element (2) and the intermediate element (3) the collar (2'") is also pushed over a length (b) into the part of smaller diameter of the first channel (10) (by way of the slit-shaped part of the recess (12)). The length of the pin (2") between the collar (2'") and the head (2') in fact corresponds to the length of this part of smaller diameter of the first channel (10). After this first phase, the walls of the body (3') have not yet sprung back into their original position, since the collar (2'"), having a diameter which is greater than the diameter of the part of smaller diameter of the channel (10), is still situated in this part of the channel (10).
In a second phase, the first coupling element (2) is slid axially until the head (2') knocks against the annular edge (11). The collar (2'") in this case leaves the channel (10) by way of the opening (8), and the walls of the body (3') spring back to their original position.
The collar (2'"), on the one hand, and the head (2'), on the other, make any axial displacement of the first coupling element (2) relative to the intermediate element (3) impossible.
The coupling and uncoupling of the first coupling element (2) can easily be carried out by hand.
The stud (4') of the second coupling element (4) has a cylindrical part of constant diameter, running from the end of the body of said coupling element (4) and passing on--by way of a slanting edge--into a part of greater, constant diameter, which passes on into a conical part.
The shape of the stud (4') corresponds to the shape of the second channel (13), and the various diameters of the stud (4') and the channel (13) are such that the stud (4') can be placed in the axial direction in the channel (13) until the conical part, the part of greater, constant diameter and the part of smaller, constant diameter of the stud (4') are situated in the part of gradually decreasing diameter, the part of greater, constant diameter and the part of smaller, constant diameter respectively of the channel (13).
During the insertion of the stud (4'), the stud (4') and/or the body (3') of the intermediate element (3) is/are elastically deformed, so that the walls of the body (3') press against the stud (4').
Due to the fact that the stud (4') also knocks with its slanting edge against the slanting edge of the channel (13), the stud (4') cannot be pulled out of the channel (10) as the result of a normal pulling force (during normal working of the weaving machine).
The various dimensions and materials are determined in such a way that the resistance to pulling out of the stud (4') is overcome by a pulling force which occurs on overloading.
Due to the fact that the pin (2") with the head (2') is a cylindrical shape, and is placed in a cylindrical channel (10) of the intermediate element, the first coupling element (2) and the intermediate element (3) can rotate relative to each other in the coupled state, on that the harness cord cannot exert any rotation effect at all on the tackle cord (1) and on the jacquard selection hook (14). After suspension, the harness cord (5) will consequently assume its free length without twisting in the cord.
The time required to make the weaving machine ready for use is significantly reduced if the first coupling elements (2) and second coupling elements (4) are suspended from respective carrying elements (25), (27) so that they can be presented together for their connection to the intermediate elements (3) (see FIGS. 8A and 8B). A preferred carrying element (25), (27) is in the form of a flat strip which is the shape of a comb and has teeth (26) which end with a crosspiece (26') projecting at either side, so that the teeth (26) are essentially T-shaped. The crosspieces (26') are hook-shaped at both their ends (26"). For the suspension of the coupling elements (2), (4), the comb (25) is disposed with the teeth (26) facing downwards.
The coupling elements (2), (4) are then strung onto the crosspieces (26') of the teeth (26), so that said crosspieces (26') extend through the transverse openings (6), (7) in the coupling elements (2), (4), with the hook-shaped end (26") projecting upwards past the body of the coupling element (2), (4).
In addition to a faster and easier connection of the harness cords to the lifting cords, such a carrying element (and the method which provides for the use thereof) provides another advantage:
The coupling elements (2), (4) can in fact be suspended from their respective carrying elements (25) during the transportation of the weaving machine, in order to prevent the cords (1), (5) connected thereto from becoming entangled. Moreover, their correct sequence is maintained in this way, which again results in a saving of time when making the connections between lifting cords (1) and harness cords (5).
This method is also particularly suitable for automation, both for coupling the first coupling element (2) to the intermediate element (3), and for coupling the second coupling element (4) top the intermediate element (3).
The device according to the invention prevents breakage of the device (24) for lifting the warp threads and all elements (14, 15, 16, 17, 1, 5, 20) lying in between and transmitting the lift, and also permits very rapid and easy coupling. The coupling and uncoupling can be carried out repeatedly without any damage to the elements (2), (3), (4).
The elements (2), (3), (4) of the device according to the invention can be of any possible external shape, for example square or hexagonal.
The elements (2), (3), (4) are preferably made of plastic.
The coupling elements (2), (4) are preferably fixed on the lifting cords (1) and the harness cords (5) respectively by injection mold in a mold.
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A coupling device allows for the rapid releasable connection of harness cords to lifting cords on weaving machines. A first coupler is connected to lifting cords and a second coupler is connected to harness cords. An intermediate coupler is removable connected to the first and second couplers. The intermediate coupler allows for quick and easy, manual or automatic, coupling and decoupling of the first and second elements. The second coupling elements and the intermediate elements are adapted so that only the connection therebetween is breakable when pulling forces are exerted thereon.
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BACKGROUND OF THE INVENTION AND RELATED ART STATEMENT
[0001] The present invention relates to a cylinder head gasket to be installed between two members, such as a cylinder head and a cylinder block of an internal combustion, to seal therebetween.
[0002] When the joint surfaces of the cylinder head and cylinder block (cylinder body) of an automobile engine is sealed, a metal cylinder head gasket is installed between the cylinder head and cylinder block and seals combustion gas, coolant water, lubricating oil, and so on.
[0003] The above-mentioned cylinder head gasket has been changed from a lamination-type metal cylinder head gasket wherein multiple sheets of metal substrates are laminated, to a cylinder head gasket with a simple structure formed by one or two metal substrates for the needs of a lightweight engine, manufacturing cost reduction, and so on. Since the cylinder head gasket is formed by one or two metal plates, and usable materials are also limited in terms of the lightweight engine, the type and number of sealing means are also limited. As a result, a relatively simplified sealing means has to be used.
[0004] Also, in recent lightweight and small-sized engines, engine rigidity has been decreased, so that in the sealing of the cylinder head gasket, providing a uniform sealing surface pressure around a cylinder bore has become difficult. More specifically, due to a structural problem around the cylinder bore of an engine member, when the gasket is tightened, there is a shortage of sealing surface pressure at the portion where the rigidity is weak. As a result, there has been a number of gas leaks in the portion where the rigidity is weak.
[0005] When even a small amount of the leaked gas penetrates a water hole or oil hole, the circulation of water or oil is blocked due to the invasion of the gas in a liquid such as water, oil, and so on. This blockage interferes with the cooling of the engine, and causes engine trouble, so that adequate measures are required.
[0006] On the one hand, when a large sealing surface pressure is provided in the nearest peripheral part of the cylinder bore in order to assure the sealing performance of the bore, the deformation of the cylinder bore with low rigidity is accelerated, and the sealing means of the gasket does not function well. As a result, it is difficult to achieve adequate sealing performance.
[0007] Most of the gas leakage of the cylinder head gasket occurs between the bores which are the portions where the load by a tightening bolt becomes weak; and on the exhaust side. More specifically, while the area of a tightening bolt hole has a large tightening load and generates excessive sealing surface pressure, the sealing surface pressure in other parts is reduced more for that, and the overall surface pressure distribution becomes unequal. The occurrence of the portion where the surface pressure is weak in the unequal surface pressure distribution causes the leakage of the combustion gas.
[0008] In order to solve the above-mentioned problem, a metal laminate gasket is proposed, wherein the width of a metal ring being inserted into a folded portion (grommet) of the cylinder bore is formed widely in such a way as to project near the tightening bolt hole from the folded portion rather than between the tightening bolt holes. The metal laminate gasket generates a well-balanced surface pressure distribution by dispersing a tightening load due to the tightening of the tightening bolt (for example, refer to Japanese Patent Publication 1).
[0009] However, although this structure has the effect of adjusting the surface pressure distribution in the folded portion, the surface pressure distribution in the bead portion cannot be adjusted.
[0010] Also, a meandering-shape portion such as a wave shape and so on in a plan view may be provided between the tightening bolt holes in the circumferential direction of the bead around the cylinder bore. However, in this case, there are problems that relatively high construction accuracy is required for a metal mold for forming the meandering portion; and the folded portion cannot be provided around the cylinder bore due to the obstacle of the meandering portion.
[0011] [Patent Document 1] Japanese Patent Publication No. 10-252894
[0012] The present invention is made in order to solve the above-mentioned problems, and the object of the invention is to provide a cylinder head gasket being able to improve the sealing surface pressure between the cylinder bores or in the intermediate portion between the tightening bolt holes on the exhaust side wherein the sealing performance of the cylinder head gasket is easily lowered, in a relatively simple structure.
[0013] Further objects and advantages of the invention will be apparent from the following description of the invention.
SUMMARY OF INVENTION
[0014] In order to achieve the above-mentioned object, a cylinder head gasket of the present invention is constituted as follows. In a single plate metal cylinder head gasket provided with a bead for sealing around a cylinder bore, or a lamination-type metal cylinder head gasket including a metal substrate with the bead, the intermediate portion between tightening bolt holes is partly formed in a pointed shape on the outside in a plan view with respect to the circumferential direction of the bead.
[0015] Incidentally, the above-mentioned pointed shape is expressed against the shape of a conventional bead formed in a concentric circle around the cylinder bore, and does not necessarily mean that the pointed shape has an acute angle portion, and means that the pointed shape includes an angle portion relative to a circumferential shape.
[0016] According to the structure, the bead between the tightening bolt holes where the surface pressure is easily lowered is partly formed in the pointed shape to the outside in a plan view with respect to the circumferential direction of the bead. As a result, the length of a seal bead of the above-described portion can be made longer in a relatively simple structure, so that the pressure receiving area of the bead can be made larger. Accordingly, the creep relaxation (permanent set in fatigue) of the pointed-shape portion becomes smaller than that of an arc-shaped bead in an usual plan view. Therefore, even between the cylinder bores where heat and so on are high and the sealing condition is bad, or in the portion of an exhaust side, excellent sealing performance can be maintained, and the sealing can be strengthened by using this structure.
[0017] Especially, through a structure with the pointed shape, compared to the case of being partly formed in a meandering portion such as a wave shape and so on in a plan view, the structure is simplified and eliminates the need for a metal mold with high accuracy. Furthermore, if the width of a folding back portion can be obtained, the folding back portion can be provided around the cylinder bore, or a bore bead ring can be built in.
[0018] Also, in the case that the pointed-shape portions are provided between all the tightening bolt holes, the tightening bolt holes are arranged in each of the intermediate positions of the pointed-shape portions in the circumferential direction of the bead. As a result, unevenness of the received surface pressures over the entire circumference of the bead is reduced.
[0019] Also, in the cylinder head gasket, if the pointed-shape portion of the bead is provided between abutting cylinder bores or if, in the cylinder head gasket, the pointed-shape portion of the bead is provided on the exhaust side, although these portions have relatively small surface pressures being generated by the tightening of the tightening bolts, the pointed-shaped portions of the bead has a profound effect.
[0020] In addition, in the cylinder head gasket, the angle of the edge of the pointed-shaped portion of the bead is within a range of 90-170 degrees. If the angle is over 90 degrees, the projecting amount of a pointed extremity is also small, so that the pointed-shape portion is easily arranged even between the cylinder bores. If the angle is below 170 degrees, the sealing effect of sharpening the edge becomes large, so that adopting the above-mentioned structure has a profound effect.
[0021] Moreover, in the cylinder head gasket, if a front edge location of the pointed-shape portion of the bead is located between a straight line connecting the outside of the tightening bolt holes on the two sides, and a straight line connecting the inside of the tightening bolt holes on the two sides, the pointed-shape portion is located in the portion where the surface pressure becomes highest among the intermediate portion of the tightening bolt holes where the surface pressure becomes low. Accordingly, the pressure receiving surface of the bead forming a sealing line can be arranged so that the effect becomes larger.
[0022] Incidentally, usually, a full bead with a circular arc is used for the cross-sectional shape of the bead for sealing around the cylinder bore of the invention. However, a full bead with a cross-sectional shape of a trapezoidal shape or other shapes may be used. Also, a bead other than the full bead such as a half bead and so on may be used. Moreover, the shape pointing outside in the plan view may have a linear shape or a combination of a curved line such as an arc and so on. The bottom portion of the pointed shape is connected to an arc-shaped portion along the bottom portion in the plan view. However, the bottom portion is preferably formed in such a way as to be smoothly connected to the periphery of the arc shape.
[0023] According to the cylinder head gasket of the invention, the pointed-shape portion of the bead provided between the cylinder bores increases the pressure receiving portion, so that the sealing surface pressure between the cylinder bores, or in the intermediate portion of the tightening bolt holes on the exhaust side where the sealing performance of the cylinder head gasket can be easily lowered can be improved in the relatively simple structure.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] FIG. 1 is a plan view showing a cylinder head gasket of a first embodiment of the present invention;
[0025] FIG. 2 is a plan view showing the cylinder head gasket of a second embodiment of the present invention;
[0026] FIG. 3 is a plan view showing the cylinder head gasket of a third embodiment of the present invention;
[0027] FIG. 4 is a plan view showing the cylinder head gasket of a fourth embodiment of the present invention; and
[0028] FIG. 5 is an enlarged plan view of one bead in FIG. 1 .
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0029] Hereinafter, embodiments of a cylinder head gasket of the present invention are explained with reference to the drawings.
[0030] Cylinder head gaskets 1 , 1 A, 1 B, 1 C of the embodiments of the present invention shown in FIGS. 1-4 are a metal gasket installed between a cylinder head and a cylinder block (cylinder body) for an engine. The gasket seals high-temperature and high-pressure combustion gas, and liquid such as coolant water in a passage for coolant water or oil in a passage for cooling oil, and so on in a cylinder bore.
[0031] Incidentally, FIGS. 1-4 are explanatory drawings shown by changing the horizontal to vertical ratio of the metal laminate gaskets 1 , 1 A, 1 B, and the number, width, or horizontal to vertical ratio of the waveform of the wave shape of a bead in a plan view from real sizes in order to understand easily.
[0032] The cylinder head gaskets 1 - 1 C of the embodiments of the present invention shown in FIGS. 1-4 are constituted by metal substrates 10 ˜ 10 C, respectively. Each of the metal substrates 10 ˜ 10 C is formed by a stainless annealed material (anneal material) or mild steel plate, and so on, and manufactured in accordance with the shape of an engine member such as a cylinder block and so on. Also, cylinder bores 2 , water holes 3 for coolant water, oil holes 4 for circulating engine oil, and tightening bolt holes 5 for tightening a bolt are formed. In addition, beads 11 - 11 C formed by full beads around the respective cylinder bores 2 are provided as sealing means. Each bead 11 surrounds each cylinder bore 2 .
[0033] In a first embodiment, the bead 11 has a partly pointed shape in a circumferential direction in the plan view between the cylinder bores 2 , and only in an intermediate portion 11 b between the tightening bolt holes 5 . A portion 11 a other than the intermediate portion 11 b is formed in a circular arc shape along the cylinder bore 2 in the plan view.
[0034] According to the structure, since the pressure receiving area of the pointed-shaped portion 11 b of the bead 11 provided between the cylinder bores 2 increases, the sealing surface pressure in the portion where the sealing performance can be easily lowered between the cylinder bores 2 of the cylinder head gasket 1 can be improved in a relatively simple structure.
[0035] In a second embodiment, as shown in FIG. 2 , in each bead 11 A for sealing each cylinder bore 2 of the metal substrate 10 A, only an intermediate portion 11 Ab between the tightening bolt holes 5 on the exhaust side (EXT side) is formed in a partially pointed shape in the plan view. A portion 11 Aa other than the intermediate portion 11 Ab is formed in a circular arc shape along the cylinder bore 2 in the plan view.
[0036] According to the structure, on the exhaust side (EXT side) where the sealing performance can be easily lowered due to a high temperature compared to the temperature on the intake side (INT side), the pressure receiving area of the pointed-shaped portion 11 Ab of the bead 11 A provided between the cylinder bores 2 increases, so that the sealing surface pressure in the portion where the sealing performance can be easily lowered between the tightening bolt holes 5 on the exhaust side (EXT side) can be improved in the relatively simple structure.
[0037] In a third embodiment, as shown in FIG. 3 , in each bead 11 B for sealing each cylinder bore 2 of the metal substrate 10 B, both of the intermediate portions 11 Bb, i.e. between the cylinder bores 2 , and between the tightening bolt holes 5 on the exhaust side (EXT side) have a partly pointed shape in the plan view. Portions 11 Ba other than the intermediate portions 11 Bb are formed in a circular arc shape along each cylinder bore 2 in the plan view.
[0038] According to the structure, since the pressure receiving areas of the pointed-shaped portions 11 Bb of the bead 11 B provided between the cylinder bores 2 and on the exhaust side (EXT side) increase, the sealing surface pressure in the portions where the sealing performance is easily lowered between the cylinder bores 2 and the tightening bolt holes 5 on the exhaust side (EXT side) of the cylinder head gasket 1 B can be improved in the relatively simple structure.
[0039] In a fourth embodiment, as shown in FIG. 4 , in the bead 11 C for sealing each cylinder bore 2 of the metal substrate 10 C, intermediate portions 11 Cb of the four tightening bolt holes 5 are formed in a partly pointed shape in the plan view. Portions 11 Ca other than the intermediate portions 11 Cb are formed in a semi circular arc shape along each cylinder bore 2 in the plan view.
[0040] According to the structure, since the pressure receiving areas of the pointed-shaped portions 11 Cb of the bead 11 C provided between the respective tightening bolt holes 5 increase, the sealing surface pressure in the portions where the sealing performance is easily lowered between the tightening bolt hole 5 of the cylinder head gasket 1 C can be improved in the relatively simple structure.
[0041] Incidentally, usually, a full bead with a circular arc cross-sectional shape is used for the beads 11 - 11 C for sealing around the cylinder bores 2 . However, beads are not limited to the circular arc full bead, and a full bead with a cross-sectional shape of a trapezoidal shape or other shapes may be used. Also, a bead other than the full bead such as a half bead may be used. Moreover, the shape pointing outside relative to the cylinder bore 2 in the plan view may have a linear shape or a combination of a curved line such as an arc and so on. The bottom portions of the pointed shape are connected to arc-shaped portions along the bottom portions in the plan view. However, the bottom portions are preferably formed in such a way as to be smoothly connected to the periphery of the arc shape.
[0042] In a shape of the pointed-shape portions 11 b, 11 Ab, 11 Bb, 11 Cb in the plan view, an angle α of an edge is preferably within a range of 90-170 degrees as exemplified in FIG. 5 . If the angle a is over 90 degrees, the projecting amount of a pointed extremity is also small, so that the pointed-shape portions are easily arranged even between the cylinder bores 2 . If the angle a is below 170 degrees, the sealing effect of sharpening the edge is large, so that adopting the above-mentioned structure has a profound effect.
[0043] Additionally, as exemplified in FIG. 5 , if a front edge location 11 c of the pointed-shape portion 11 b of the bead 11 is located between a straight line (dashed-dotted line) connecting the outside of the tightening bolt holes 5 on the two sides, and a straight line (dashed-two dotted line) connecting the inside of the tightening bolt holes 5 on the two sides, the pointed-shaped portion 11 b is located in the portion where the surface pressure becomes the highest among the intermediate portion of the tightening bolt holes where the surface pressure becomes low. Accordingly, the pressure receiving surface of the bead 11 forming a sealing line can be arranged so that the effect becomes larger.
[0044] According to the cylinder head gaskets 1 - 1 C of the first to fourth embodiments of the above-mentioned structure, the pointed-shape portions 11 b - 11 Cb of the beads 11 - 11 C are provided between the tightening bolt holes 5 , and the pressure receiving areas of the beads 11 - 11 C increase. As a result, the beads can endure high tightening pressure and provide sealing performance with excellent anti-creep relaxation.
[0045] Therefore, the sealing surface pressure of the intermediate portions 11 b - 11 Cb between the cylinder bores 2 or between the tightening bolt holes 5 on the exhaust side (EXT side) where the sealing performance of the cylinder head gaskets 1 - 1 C can be easily lowered can be improved in the relatively simple structure.
[0046] Incidentally, in the above-mentioned embodiments, a single plate metal cylinder head gasket formed by a single metal substrate is explained. However, the present invention can be also applied to a lamination-type metal cylinder head gasket where multiple sheets of metal substrates are laminated.
[0047] The disclosure of Japanese Patent Application No. 2005-163749 filed on Jun. 3, 2005 is incorporated as a reference.
[0048] While the invention has been explained with reference to the specific embodiments of the invention, the explanation is illustrative, and the invention is limited only by the appended claims.
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A cylinder head gasket includes a metal plate having at least one cylinder bore and a plurality of bolt holes arranged around the at least one cylinder bore. A bead is formed on the metal plate to surround the at least one cylinder bore. The bead has at least one pointed shape portion pointed outwardly between two of the bolt holes.
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TECHNICAL FIELD
The invention relates generally to analysis of motion in video sequences and, more particularly, to identifying pan and zoom global motion in video sequences.
BACKGROUND
The analysis of motion information in video sequences has typically addressed two largely non-overlapping applications: video retrieval and video coding. In video retrieval systems, the dominant motion, motion trajectories and tempo are computed to identify particular video clips or sequences that are similar in terms of motion characteristics or belong to a distinct class (e.g., commercials). In video coding systems, global motion parameters are estimated for global motion compensation and for constructing sprites. In both video retrieval and video coding systems, it is desirable to identify pan and zoom global motion. For video retrieval systems, pan and zoom detection enables classification of video sequences (e.g., documentary movies) for efficient retrieval from video databases. For video coding systems, pan and zoom detection enables the adaptive switching of coding parameters (e.g., the selection of temporal and spatial Direct Modes in H.264).
Previous methods for detecting pan and zoom global motion in video sequences require estimating parameters of global motion, i.e., motion such that most of the image points are displaced in a uniform manner. Because the motion of many image points in a video frame is described by a small set of parameters related to camera parameters, estimating global motion parameters is a more constrained case than the estimation of motion parameters in all image points. The number of parameters obtained depends on the global motion model that is assumed to best describe the motion in the video sequence, for example, translational, affine, perspective, quadratic, etc., yielding 2, 6, 8 and 12 parameters, respectively. In particular, a perspective motion model yields the estimated coordinates {circumflex over (x)}, ŷ using the old coordinates x i , y i and the equations:
{circumflex over (x)} i =( a 0 +a 2 x i +a 3 y i )/( a 6 x i +a 7 y i +1) (1)
ŷ i =( a 1 +a 4 x i +a 5 y i )/( a 6 x i +a 7 y i +1) (2)
where a 0 . . . a 7 are the motion parameters. Other models can be obtained as particular cases of the perspective model. For example, if a 6 =a 7 =0, the affine model (six parameters) is obtained, if a 2 =a 5 , a 3 =a 4 =a 6 =a 7 =0, the translation-zoom model (three parameters) is obtained, and if a 2 =a 5 =1, a 3 =a 4 =a 6 =a 7 =0, the translational model (two parameters) is obtained.
Global motion estimation can be formulated as an optimization problem, where the error between a current frame and a motion compensated previous frame is minimized. Techniques such as gradient descent and second order optimization procedures have been applied iteratively to solve the optimization problem. In Hirohisa Jozawa, et al., “Two-stage Motion Compensation Using Adaptive Global MC and Local Affine MC,” IEEE Trans. on Circuits and Systems for Video Tech ., Vol. 7, No. 1, pp. 75-82, February 1997, global motion parameters are estimated using a two-stage motion compensation process. In the first stage, global motion is estimated and a global motion compensated picture is obtained. In the second stage, the global motion compensated picture is used as a reference for local motion compensation. The local motion compensation is performed both for the global motion compensated reference image and for the image without global motion compensation using an affine motion model in the framework of the H.263 standard.
Other techniques for estimating global motion in video sequences have also been proposed. A technique proposed in Frederic Dufaux et al., “Efficient, Robust and Fast Global Motion Estimation for Video Coding,” IEEE Trans. on Image Processing , Vol. 9, No. 3, pp. 497-510, March 2000, includes a three-stage process. In a first stage, a low pass image pyramid is constructed by successive decompositions of the original picture. In a second stage, an initial estimation is performed, followed by a refining of the initial estimate, using gradient descent-based in a third stage. A perspective model with eight parameters has been used in this technique to model camera motion.
In Gagan B. Rath, et al., “Iterative Least Squares and Compression Based Estimation for a Four-Parameter Linear Global Motion Model and Global Motion Compensation,” IEEE Trans. on Circuits and Systems for Video Tech ., Vol. 9, No. 7, pp. 1075-1099, October 1999, a four-parameter model for global motion is employed for pan and zoom motion estimation. This technique uses iterative least squares estimation to accurately estimate parameters.
In Patrick Bouthemy, et al., “A Unified Approach to Shot Change Detection and Camera Motion Characterization,” IEEE Trans. on Circuits and Systems for Video Tech ., Vol. 9, No. 7, pp. 1030-1040, October 1999, a unified approach to shot change detection and camera motion characterization is proposed. By using an affine motion model, global motion parameters are estimated and at the same time, the evolution of scene cuts and transitions is evaluated.
In Yap-Peng, et al., “Rapid Estimation of Camera Motion from Compressed Video With Application to Video Annotation,” IEEE Trans. on Circuits and Systems for Video Tech ., Vol. 10, No. 1, pp. 133-146, February 2000, camera motion parameters are estimated from compressed video, where macroblocks from P frames are used to estimate the unknown parameters of a global motion model.
All of the conventional methods described above require estimating global motion parameters to identify a specific type of global motion (e.g., pan, zoom or other). To estimate global motion, however, these conventional methods employ a generic motion model having global motion parameters that must be estimated. These global motion parameters are not necessary, however, for retrieving video sequences from databases. Nor are these global motion parameters necessary for parameter switching in video coding systems. Therefore, the conventional methods described above for estimating global motion increase unnecessarily the computational complexity of the application systems that employ such techniques.
Video retrieval systems can benefit from pan and zoom detection, which would allow identification of documentary movies and other sequences in video databases. Documentary movies include, for example, long panning clips that have a typical length of at least 10 seconds (i.e., 240 frames for a frame rate of 23.976 fps). These long panning clips are often preceded or followed by zooms on scenes or objects of interest. Pan and zoom clips are also present in numerous other types of sequences, from cartoons and sports games to home videos. It is therefore of interest to retrieve video clips and sequences having common pan or zoom characteristics.
Pan and zoom detection in video sequences can also enhance the capabilities of an encoder in a standards compliant system. It is well-known that encoders that are compliant with the MPEG and ITU standards may be unconstrained in terms of analysis methods and parameter values selections, as well as various coding scenarios for given applications, as long as the resulting compressed bit streams are standards-compliant (i.e., can be decoded by any corresponding standardized decoder). The objective of performing various enhancements at the encoder side is bit rate reduction of the compressed streams while maintaining high visual quality in the decoded pictures. An example of such enhancement is the selection of temporal and spatial Direct Modes described in the H.264 video coding standard.
In H.264, each frame of a video sequence is divided into pixel blocks having varying size (e.g., 4×4, 8×8, 16×16). These pixel blocks are coded using motion compensated predictive coding. A predicted pixel block may be an Intra (I) pixel block that uses no information from preceding pictures in its coding, a Unidirectionally Predicted (P) pixel block that uses information from one preceding picture, or a Bidirectionally Predicted (B) pixel block that uses information from one preceding picture and one future picture. The details of H.264 can be found in the publicly available MPEG and ITU-T, “Joint Final Committee Draft of Joint Video Specification ISO/IEC/JTC1/SC29/WG11 (MPEG) 14496-10 and ITU-T Rec. H.264,” Geneva, October 2002, which is incorporated by reference herein in its entirety.
For each pixel block in a P picture, a motion vector is computed. Using the motion vector, a prediction pixel block can be formed by translation of pixels in the aforementioned previous picture. The difference between the actual pixel block in the P picture and the prediction block is then coded for transmission. Each motion vector may also be transmitted via predictive coding. That is, a prediction is formed using nearby motion vectors that have already been sent, and then the difference between the actual motion vector and the prediction is coded for transmission. For each B pixel block, two motion vectors are typically computed, one for the aforementioned previous picture and one for the future picture. From these motion vectors, two prediction pixel blocks are computed, which are then averaged together to form the final prediction. The difference between the actual pixel block in the B picture and the prediction block is then coded for transmission. Each motion vector of a B pixel block may be transmitted via predictive coding. That is, a prediction is formed using nearby motion vectors that have already been transmitted, then the difference between the actual motion vector and the prediction is coded for transmission.
With B pixel blocks, however, the opportunity exists for interpolating the motion vectors from those in the co-located or nearby pixel blocks of the stored pictures. Note that when decoding a B slice, there exist two lists (list 0 and list 1) of reference pictures stored in the decoded picture buffer. For a pixel block in a B slice, the co-located pixel block is defined as a pixel block that resides in the same geometric location of the first reference picture in list 1 or nearby pixel blocks of the stored pictures. The former case is known as the temporal-direct mode. The latter case is known as the spatial direct mode. In both of these cases, the interpolated value may then be used as a prediction and the difference between the actual motion vector and the prediction coded for transmission. Such interpolation is carried out both at the coder and decoder. In some cases, the interpolated motion vector is good enough to be used without any correction, in which case no motion vector data need be sent. Note that the prediction error of a pixel block or subblock, which is computed as the mean square error between the original pixel block and the decoded pixel block after encoding using direct mode is still transformed, quantized and entropy encoded prior to transmission. This is referred to as Direct Mode in H.264 (and H.263). Direct Mode selection is particularly effective when the camera is slowly panning across a stationary background. Indeed, the interpolation may be good enough to be used as is, which means that no differential information need be transmitted for these B pixel block motion vectors. Therefore, for such sequences that allow good motion vector predictions using neighboring temporal or spatial information, the Direct Mode can provide important bit rate savings.
Accordingly, there is a need for a system and method for pan and zoom detection in video sequences that enable classification of video sequences (e.g., documentary movies) in video retrieval systems and adaptive switching of coding parameters (e.g., selection of temporal and spatial Direct Modes in H.264) video coding systems, without performing the computationally intensive task of estimating all the parameters of a global motion model.
SUMMARY
The present invention overcomes the deficiencies of the prior art by providing a look-ahead system and method for pan and zoom detection in video sequences based on motion characteristics.
One aspect of the present invention includes a method of detecting pan and zoom in a video sequence. The method comprises selecting a set of frames from a video sequence (e.g., by identifying scene cuts), determining a set of motion vectors for each frame in the set of frames, identifying at least two largest regions in each frame in the frame set having motion vectors with substantially similar orientation in a reference coordinate system (e.g., polar coordinates), determining percentages of each frame covered by the at least two largest regions, determining a statistical measure (e.g., variance) of the motion vector orientations in the reference coordinate system for at least one of the two largest regions, and comparing the percentages and statistical measure to threshold values to identify a pan or zoom in the video sequence.
Another aspect of the present invention includes a system for detecting pan and zoom sequences in a video sequence. The system comprises: a preprocessor for selecting a set of frames from a video sequence, and a motion analyzer for determining a motion vector for each frame in the set of frames, identifying the two largest regions in each frame having motion vectors with substantially similar orientation in a reference coordinate system, determining percentages of each frame covered by the two largest regions, determining a statistical measure of the motion vector orientations in the reference coordinate system for at least one of the two largest regions, and comparing the percentages and statistical measure to threshold values to identify a pan or zoom in the video sequence.
The present invention as defined by the claims herein provides a computationally efficient solution for identifying pans and zooms in video sequences, including but not limited to the enabling of parameter switching for improved encoding in video standards (e.g., H.264) and improved video retrieval of video sequences from databases and other video storage devices.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram of a video retrieval system, in accordance with one embodiment of the present invention.
FIG. 2 is a block diagram of a video encoder, in accordance with one embodiment of the present invention.
FIG. 3 is a flow diagram of a look-ahead method for pan and zoom detection in video sequences, in accordance with one embodiment of the present invention.
FIG. 4 illustrates the identification of the two largest regions in a video frame k, which form part of a look-ahead video clip, in accordance with one embodiment of the present invention.
DETAILED DESCRIPTION
While the embodiments described below include a video retrieval system and a video encoder (with parameter switching capability), the present invention is equally applicable to any video systems that employ pan and/or zoom detection to perform for a particular application.
Video Retrieval Application
FIG. 1 is a block diagram of a video retrieval system 100 , in accordance with one embodiment of the present invention. The video retrieval system 100 includes a query analyzer 102 , a comparison block 114 and an image database 116 . The query analyzer 102 includes one or more analysis blocks, including but not limited to a text analysis block 104 , a texture analysis block 106 , a shape analysis block 108 , a motion analysis block 110 and a look-ahead detector 112 . In one embodiment, the analysis blocks 104 , 106 , 108 , 110 , and the look-ahead detector 112 , are implemented as software instructions stored on a computer-readable medium and executed by one or more processors in the video retrieval system 100 .
The query analyzer 102 receives one or more queries (e.g., text, images, image regions, image features, etc.) and analyzes the queries with one or more of the analysis blocks 104 , 106 , 108 and 110 . For example, the text analysis block 104 analyzes text queries, the texture analysis block 106 analyzes textures, the shape analysis block 108 analyzes shapes and the motion analysis block 110 analyzes motion. The motion analysis block 110 also provides motion vectors to the look-ahead detector 112 . The look-ahead detector 112 uses the motion vectors to perform pan and zoom detection in accordance with the present invention. The query analyzer 102 provides query indices to the comparison block 114 , which compares the query indices with database indices provided by the image/video database 116 . If there is a match between a query index and a database index, then the comparison block 114 generates a match index, which is used to retrieve a video sequence, image or image region from the image/video database 116 .
The video retrieval system 100 uses the look-ahead detector 112 to identify pans and zooms in video sequences for improved retrieval of video sequences, such as documentaries. More particularly, the look-ahead detector 112 transforms block-based motion vectors from the motion analysis block 110 to polar coordinates to detect pan and zoom sequences without computing global motion parameters. The various steps performed by the look-ahead detector 112 are described more fully with respect to FIG. 3 .
Video Coding Application
FIG. 2 is a block diagram of a video encoder 200 , in accordance with one embodiment of the present invention. The video encoder 200 includes a preprocessor 202 , a video sequence analyzer 204 , a parameter selector 212 and a compressor 214 . The video sequence analyzer 204 includes a text analysis block 206 , a motion analysis block 208 and a look-ahead detector 210 . The look-ahead detector 210 is coupled to the motion analysis block 208 and receives motion vectors from the motion analysis block 208 . In one embodiment, the analysis blocks 204 , 206 , 208 , and the look-ahead detector 210 , are implemented as software instructions stored on a computer-readable medium and executed by one or more processors.
In normal operation, the preprocessor 202 may perform tasks such as color space conversions, spatial, temporal or spatio-temporal filtering, or down sampling. The texture analysis block 206 performs a texture analysis for each macroblock and the motion analysis block 208 performs motion analysis for each macroblock. The video sequence analyzer 204 provides data (e.g., pan or zoom detection signals) to the parameter selector 212 , which provides parameter switching for improved encoding (e.g., adaptive switching of temporal and spatial direct modes in H.264).
Pan and Zoom Detection
FIG. 3 is a flow diagram of a look-ahead method for pan and zoom detection in video sequences, in accordance with one embodiment of the present invention. For each group of F frames, a look-ahead video clip is determined 300 by identifying a first scene cut between a first and the Fth frame of a group of frames. Various methods have been employed to identify scene cuts in video sequences. For simplicity, this embodiment of the present invention makes use of frame differences and motion information to identify a scene cut. In one embodiment of the present invention, if the relative difference between two adjacent frames with respect to the first of these frames is larger than a predetermined threshold (e.g. 20%) or if the motion vectors in the second of these frames are equal to zero, then a scene cut is identified. If a scene cut is identified between frames F c and F c +1, then the look-ahead video clip includes 302 frames from the first frame to the frame F c . If there exists no scene cut, then the look-ahead video clip includes 304 frames from the first frame of the group frames to the Fth frame.
For each frame of the look-ahead video clip, motion vectors are computed 306 using, e.g., 8×8 macroblocks to make use of block-based motion information to characterize global motion in the video sequence. In one embodiment, motion vector data (e.g., one motion vector for each 8×8 block) is obtained by motion estimation using techniques such as those disclosed in the publicly available H.264 standard (e.g., reference H.264 encoder version 6.1). Note that other block sizes can be used with the present invention depending upon the application and motion estimation method using various block sizes (e.g., 4×4, 16×16 pixels).
The angle theta of each of the motion vectors is computed 308 in polar coordinates (r, θ), where r is the modulus and theta is the angle of a motion vector. More specifically, the angle θ of a motion vector is given by:
θ = a tan ( y x ) , ( 3 )
where (x, y) are the Cartesian coordinates (displacements) on the x, y directions, respectively. Preferably, the value of theta is normalized between 0 and 1. Note that other reference coordinate systems can be use with the present invention, such as Cartesian, spherical, cylindrical and the like.
Next, the two largest regions in each frame containing motion vectors with similar orientation (e.g., values for theta are substantially similar) are identified 310 . Mathematically, the regions R k (1) and R k (2) are given by the following equations:
R k (1) ={( i,j ),1 ≦i≦M, 1 ≦j≦N |θ( i,j )≈const. (4)
and A k (1) =max allA m in framek {A m }} (5)
R k (2) ={( i,j ),1 ≦i≦M, 1 ≦j≦N |θ( i,j )≈const. (6)
and A k (2) =max allA m |A l in frame k {A m }} (7)
where (i, j) are the locations of pixels in a frame, M, N are the width and height of a frame, A k (1) and A k (2) are the areas (e.g., in number of pixels) of the first and second largest regions R k (1) and R k (2) , respectively, which contain motion vectors having similar orientation based on the values for theta computed using Equation (3).
FIG. 4 illustrates pan and zoom detection in a frame k in a look-ahead video clip 400 comprising multiple frames. The frame k includes first and second largest regions 402 , 404 , which correspond to R k (1) and R k (2) in equations (4) and (6) above.
Next, the percentages covered by the regions R k (1) and R k (2) within each frame are computed 312 and the variance of the θ values in the first largest region R k (1) of each frame is computed 314 . More specifically, the percentages P k (1) and P k (2) covered within each frame by the regions R k (1) and R k (2) with similar orientation of the motion vectors are given by
P k (1) =A k (1) ×100/( M×N ), P k (2) =A k (2) ×100/( M×N ), (8)
where A k (1) is the area (e.g., in number of pixels) of the first largest region R k (1) and A k (2) is the area (e.g., in the number of pixels) of the second largest region R k (2) with motion vectors having similar orientation (e.g., substantially similar theta values). The variance of the theta values within the first largest region R 1 k is given by
var (1) (θ)={var(θ)|θε R k 1 } (9)
The above steps are repeated for each frame in the look-ahead video clip until the last frame of the video clip is reached 316 . Note the variance of the theta values within the second largest region R k (2) can also be computed instead of the theta values for R 1 k , but this is unnecessary for the present invention. The percentages and variances computed in the previous steps are then tested 318 to identify if a pan video clip is present and tested 320 to identify if a zoom video clip is present in the video clip, as follows:
If (( P k (1) +P k (2) )>ε 1 ) and var (1) (θ)<ε 2 , then pan, (10)
If (( P k (1) +P k (2) )<ε 3 ) and var (1) (θ)<ε 2 , then zoom, (11)
where one exemplary set of threshold values ε 1 , ε 2 and ε 3 are determined experimentally to be equal to ε 1 =0.95, ε 2 =0.01, and ε 3 =0.5. Note that these threshold values can be adjusted as desired to increase or decrease the number of possible pan and zoom detections. The preceding steps 300 to 322 are repeated until the last group of frames is reached 322 , and then a new group of frames is processed.
Because the present invention does not compute global motion parameters, it provides a simpler and more computationally efficient system and method for pan and zoom detection than conventional systems and methods, which require the computation of global motion parameters for a global motion model.
The foregoing description of the embodiments 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 this disclosure. It is intended that the scope of the invention be limited not by this detailed description, but rather by the claims appended hereto.
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A look-ahead system and method for pan and zoom detection in video sequences is disclosed. The system and method use motion vectors in a reference coordinate system to identify pans and zooms in video sequences. The identification of pans and zooms enables parameter switching for improved encoding in various video standards (e.g., H.264) and improved video retrieval of documentary movies and other video sequences in video databases or other storage devices.
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REFERENCE TO PRIOR APPLICATION
This is a continuation-in-part of U.S. patent application Ser. No. 419,809, filed on Nov. 28, 1973 now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to pharmacologically active compounds useful in the treatment of allergic and inflammatory conditions, particularly allergic asthma and hay fever. Those compounds are classifiable in U.S. Classes 260/308D and 260/345.2 and in International Class C07d 7/34.
2. Description of the Prior Art
U.S. Pat. No. 3,882,148 (5/75; "Augstein") discloses a genus of compounds having the structure, ##STR1## in which: each of substituents R 1 -R 5 and R 7 can be a hydrogen atom, a hydroxyl, alkoxyl, benzyloxyl, acyl, amino, acylamino, alkenyl, halogeno, or an alkyl group; X can be a hydrocarbon chain of from 2 to 10 carbon atoms optionally substituted by a hydroxyl group; and E can be a tetrazolyl or carboxyl group.
Because I contains structural features not germane to the present invention, it is convenient to simplify that formula to ##STR2## in which R can be a hydrogen atom, a halogeno, hydroxyl, or an alkyl group. While Augstein does not provide specific examples of Ia, that reference nevertheless provides generic disclosure of those compounds. The disclosure in Augstein, however, does not include compounds having structure I or Ia in which R is a cyano group.
Augstein discloses that compounds having structural formula I are useful in the treatment of disorders in which SRS-A (slow reacting substance of anaphylaxis) is a factor, such as asthma, hay fever, skin disorders and diseases of the respiratory system.
U.S. Pat. No. 3,899,513 (8/75; "Warren") describes compounds having the structure, ##STR3## in which: R 1 can be a hydrogen atom, a nontoxic cation, or an alkyl group of 1 to 4 carbon atoms. Compounds III are useful as starting materials for those disclosed in this specification. Warren teaches that compounds III are useful in the treatment of allergic conditions.
Example 5 of this specification demonstrates that the claimed compounds have therapeutic indices superior those of compounds Ia and III.
SUMMARY OF THE INVENTION
The subject matter of this invention includes: 1-(4-cyano-phenoxy)-2-hydroxy-3-[2-(5-1H-tetrazolyl)-chromon-5-yloxy]-propane and its pharmacologically acceptable, non-toxic salts; a process for preparing that compound; intermediates that are useful in the process; and a therapeutic method of producing an anti-allergic effect in mammals or in man utilizing 1-(4-cyano-phenoxy)-2-hydroxy-3-[2-(5-1H-tetrazolyl)-chromon-5-yloxy]-propane and its salts.
1-(4-Cyano-phenoxy)-2-hydroxy-3-[2-(5-1H-tetrazolyl)-chromon-5-yloxy]-propane has the structure, ##STR4## Pharmacologically acceptable, non-toxic salts of IV include, for example, the sodium, dimethylaminoethanol, and trishydroxymethylaminomethane salts.
Compound IV is prepared by the following process:
(1) reacting 1-(4-cyano-phenoxy)-2-hydroxy-3-(2-carbalkoxychromon-5-yloxy)-propane, ##STR5## in which R is an alkyl group of from 1 to 4 carbon atoms, with ammonia in a solvent such as ethanol, chloroform, or a chloroform/ethanol mixture, at from -5%C. to 10° C. to obtain the corresponding amide, 1-(4-cyano-phenoxy)-2-hydroxy-3-(2-amido-chromon-5-yloxy)-propane, ##STR6##
(2) dehydrating the amide at a temperature of from 40° C. to 60° C. with a reagent mixture such as p-toluenesulfonyl chloride/pyridine, p-toluenesulfonyl chloride/colidine, or p-toluenesulfonyl chloride/lutidine in dimethylformamide to obtain the corresponding nitrile, 1-(4-cyano-phenoxy)-2-formyloxy-3-(2-cyano-chromon-5-yloxy)-propane: ##STR7##
(3) reacting the nitrile with sodium azide and ammonium or sodium chloride in an organic solvent such as dimethylformamide, dimethylsulfoxide, or dimethylacetamide to obtain a corresponding salt of a tetrazolyl derivative, ##STR8## wherein X is a sodium, or ammonium cation; and,
(4) treating the tetrazolyl derivative with a dilute mineral acid to acidify the salt and to hydrolyze the formyl group thereof to obtain compound IV.
Step (3) of the process optionally may be carried out with an alkali-metal azide such as sodium, potassium, or lithium azide without ammonium or sodium chloride; in that case, X + in VIII is a sodium, potassium, or lithium cation.
Starting materials V are prepared as follows:
(1) reacting 2,6-dihydroxyacetophenone, ##STR9## with 4-cyanophenylglycidyl ether, ##STR10## in 2-ethoxyethanol in the presence of benzyltrimethylammonium hydroxide to obtain a bis-(substituted-phenoxy)-propane, ##STR11##
(2) recovering the (bis-phenoxy)-propane and reacting it with diethyl oxalate to obtain an intermediate, ##STR12##
(3) recovering the intermediate and reacting it with a cyclization mixture such as concentrated hydrochloric acid and a lower alcohol of 1 to 4 carbon atoms, thus obtaining compound IV. Details of the preceding synthesis are available in Warren (U.S. Pat. No. 3,899,513).
1-(4-Cyano-phenoxy)-2-hydroxy-3-(2-amido-chromon-5-yloxy)propane (VI) and 1-(4-cyano-phenoxy)-2-formyloxy-3-(2-cyano-chromon-5-yloxy)-propane are key intermediates in the synthesis of compound IV.
Compound IV and its non-toxic salts possess anti-allergic properties that make them useful in treating allergic, asthmatic, and certain inflammatory conditions; those compounds may also be useful in treating autoimmune diseases. An anti-allergic effect is produced in an individual in need of such therapy by administration of an effective amount of compound IV or a pharmacologically acceptable salt thereof. The term "individual" means a human being or an experimental animal used as a model thereof. The compounds may be administered by inhalation, injection, ingestion, or other suitable routes of administration. Effective doses range from 0.075 to 2.25 μmole/kg. Succeeding example 5 provides details of the method.
Compound IV and its salts also have anti-inflammatory activity upon topical application to inflammed areas of the skin or of the eye.
For the treatment of asthma, compound IV or a salt thereof may be in a form suitable for administration by inhalation. That form can comprise a suspension or solution of the active ingredient in water or in a suitable alcohol for administration as an aerosol by means of a conventional nebulizer. Alternatively, that form can comprise a suspension or solution of the active ingredient in a conventional liquefied propellant to be administered as an aerosol from a pressurized container. The forms for administration can comprise the solid active ingredient in a solid diluent for administration from a powder inhalation device. Other routes of administration: e.g. sublingual, oral or buccal tablets; rectal suppositories; parenteral injection; or intravenous infusion; can also be used.
The form for administration can also contain, in addition to compound IV, other active bronchodilating ingredients, e.g. those of the β-adrenergic type, such as iso- or orciprenaline or salbutamol. The forms for administration can contain 0.1 to 10% by weight of compound IV or a salt thereof. If salbutamol or iso- or orci-prenaline sulphate are used, they are suitably present in a concentration of 0.1 to 5% by weight.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Example 1
1-(4-CYANO-PHENOXY)-2-HYDROXY-3-(2-AMINO-CHROMON-5-YLOXY)PROPANE (MONOHYDRATE)
In a 12 L, 3-necked flask equipped with stirrer, thermometer and gas-inlet tube were placed 832 g (2.03 moles) of 1-(4-cyano-phenoxy)-2-hydroxy-3-(2-carbethoxychromon-5-yloxy) propane, 3.7 L of chloroform and 3.3 L of 95% ethanol. The slurry was warmed to 35° C. to obtain a clear solution. The solution was then slowly cooled to 10° C. while ammonia gas was introduced into the solution at a rapid rate and kept at 10° C. until it was saturated with ammonia. The solution again was cooled and kept at 0°-5° C. while ammonia was being introduced (at a slower rate) for an additional 4-6 hours. The resulting precipitate was collected by filtration, washed with ethanol and then with ether: 695 g (86% yield); m.p. 203°-204° C.
Analysis: Calculated for C 20 H 16 N 2 O 6 .H 2 O: C, 60.30; H, 4.56; N, 7.03. Found: C, 60.55; H, 4.34; N, 7.01. TLC R f =0.22 (toluene-ethyl formate-formic acid 4:5:1).
Example 2
1-(4-CYANO-PHENOXY)-2-FORMYLOXY-3-(2-CYANO-CHROMON-5-YLOXY)PROPANE (MONOHYDRATE).
In a 12, 3-necked flask equipped with a stirrer and thermometer were placed 1945 g of p-toluenesulfonyl chloride, 1945 g of pyridine and 1690 ml of dimethylformamide (DMF). The solution was stirred while 695 g (1.745 moles) of 1-(4-cyano-phenoxy)-2-hydroxy-3-(2-amidochromon-5-yloxy)-propane (monohydrate) were added portionwise, keeping the temperature between 50°-60° C. with the aid of a cold water bath. The addition required about 30 min. After being stirred and heated at 50°-55° C. for an additional 1 hour, the reaction mixture was cooled to 25° C., and 5 L of chloroform was added. The dark solution was then poured into 5 L of ice-water and made acid with 530 ml of concentrated hydrochloric acid. The chloroform layer was separated and washed twice with 2 L portions of water. After stripping off the solvent on a rotary evaporator, the residue was slurried in 4.0 L of ethanol. The product was collected by filtration, washed with ethanol, and then with ether: 565 g (80% yield); m.p. 153°-154° C.
Analysis: calculated for C 21 H 14 N 2 O 6 .H 2 O: C, 61.76; H, 3.95; N, 6.86. Found: C, 61.63; H, 3.41; N, 6.73. TLC R f =0.58 (toluene-ethyl formate-formic acid 5:4:1).
Example 3
1-(4-CYANO-PHENOXY)-2-HYDROXY-3-[2-(5-1H-TETRAZOLYL)CHROMON-5-YLOXY]-PROPANE
In a 5 L three-necked flask equipped with a stirrer, thermometer, and reflux condenser were placed 565 g (1.38 moles) of 1-(4-cyanophenoxy)-2-formyloxy-3-(2-cyanochromon-5-yloxy)propane (monohydrate), 153 g of sodium azide, 119 g of ammonium chloride and 2.8 L of DMF. The mixture was stirred and heated at 90° C. for 3 hours.
The reaction mixture was then stripped of DMF on a rotary evaporator. The residue was dissolved in 4.5 L of acetone and 450 ml of water; 50 ml of concentrated sulfuric acid was added, the solution stirred, and refluxed for 1 hour.
An additional 2.5 L of water was added to the hot solution. The acetone was removed by distillation until the internal temperature reached 80° C. The reaction mixture was then stirred at room temperature overnight.
The product was collected by filtration and washed with water: 525 g; m.p. 219°-221° C.
The crude material was dissolved in a hot solution of 5.25 L of dioxane and 1.05 L of water. After treatment with activated charcoal and filtration, the filtrate was stripped of solvent on a rotary evaporator keeping the temperature below 40° C. The residue was slurried in 2.5 L of hot methanol and then cooled in an ice-bath. The light cream-colored solid was collected by filtration and washed with cold methanol. After drying at 60° C. the solvated material was slurried in 2.0 L of toluene and slowly heated to boiling. After boiling for 10-15 minutes, the product was collected by filtration; 441 g (80° yield); m.p. 223° C.
Analysis: calculated for C 20 H 15 N 5 O 5 : C, 59.25; H, 3.73; N, 17.28. Found: C, 59.37; H, 3.61; N, 17.12. TLC R f =0.20 (toluene-ethyl formate-formic acid 5:4:1).
Alternatively, the above procedure can be carried out by utilizing an alkali-metal azide such as sodium, potassium, or lithium azide without the presence of sodium or ammonium chloride.
In a 250 ml Erlenmeyer flask was placed 125 ml of dimethylformamide, 20.4 g (0.05 moles) of 1-(4-cyanophenoxy)-2-formyloxy-3-(2-cyanochromon-5-yloxy) and 3.3 g (0.05 moles) of sodium azide. The mixture was stirred and heated at 90° C. for 1.5-2 hours; it then was cooled and filtered. The solvent was removed in vacuo and the residue dissolved in water. Then 8 g of sodium carbonate was added, and the aqueous solution was heated at 80° C., for 30 minutes. After cooling the solution to room temperature, 300 ml of acetone was added, and the resulting solution acidified with concentrated sulfuric acid. After distillation of the acetone the residual slurry was cooled in an ice-bath and 1-(4-cyano-phenoxy)-2-hydroxy-3-[2-(5-1H-tetrazolyl)-chromon-5-yloxy)]-propane was collected by filtration: 20.4 g (96.4% yeild), m.p. 219°-221° C. TLC: R f =0.20 (toluene-ethyl formate-formic acid 5:4:1).
Example 4
SODIUM 1-(4-CYANOPHENOXY)-2-HYDROXY-3-[2-(5-1H-TETRAZOLYL)CHROMON-5-YLOXY]-PROPANE
In a 5.0 L, three-necked flask equipped with a stirrer and reflux condenser were placed 441 g (1.09 moles) of 1-(4-cyanophenoxy-2-hydroxy-3-[2-(5-1H-tetrazolyl)chromon-5-yloxy]propane, 90.7 g (1.08 moles) of sodium bicarbonate, 1.90 L of methanol, and 1.90 L of tetrahydrofuran. The mixture was stirred and heated at reflux for 5 hours. The hot slurry was filtered and the white product washed with a 50:50 mixutre of methanol and tetrahydrofuran and then with ether: 420 g (90% yield); m.p. 308° C.
Analysis: calculated for C 20 H 14 N 5 O 5 Na: C, 56.20; H, 3.30; N, 16.39. Found: C, 55.75; H, 3.23; N, 16.36. TLC R f =0.20 (toluene-ethyl formate-formic acid 5:4:1).
Example 5
ANTI-ALLERGIC ACTIVITY
Compounds described in above examples 3 and 4 were evaluated for anti-allergic activity in the rat by the passive cutaneous anaphylaxis test (hereafter PCA), utilizing egg albumin as the antigen.
PCA is an experimentally induced allergic reaction which develops in the skin of test animals after intravenous injection of an antigen. The intensity of such PCA reactions is assessed by measuring the diameters of wheals which develop in the skin of the test animals. Details of the PCA test can be found in the following references: I. Mota, Life Sciences, 1: 465 (1963); and B. Ogilvie, Immunology, 12: 113 (1967).
In the following table, ID50 is the dose which reduced the diameter of the wheal by 50% when injected intravenously together with the antigen. LD50 is the intravenous dose that caused death in 50% of the test animals. Therapeutic index is the ratio, LD50/ID50. The reference compounds utilized were: disodium chromoglycate (DSCG); 1-(phenoxy)-2-hydroxy-3-[2-(5-1H-tetrazolyl)-chromon-5-yloxy]-propane; 1-(4-chloro-phenoxy)-2-hydroxy-3-[2-(5-1H-tetrazolyl)-chromon-5-yloxy]-propane; 1-(4-hydroxy-phenoxy)-2-hydroxy-3-[2-5-1H-tetrazolyl)-chromon-5-yloxy]-propane; 1-(4-propyl-phenoxy)-2-hydroxy-3-[2-5-1H-tetrazolyl)-chromon-5-yloxy]-propane; and sodium 1-(4-cyano-phenoxy)-2-hydroxy-3-(2-carboxy-chromon-5-yloxy)-propane.
TABLE__________________________________________________________________________COMPARISON OF CLAIMED AND REFERENCED COMPOUNDS ##STR13## ID50 (i.v.) LD50 (i.v.)REFERENCE R.sup.1 R.sup.2 μmol/kg μmol/kg THERAPEUTIC INDEX__________________________________________________________________________Augstein ##STR14## H OH Cl C.sub.3 H.sub.7 2.25 0.675 1.8 >25.0 >1051 >1263<4952 >1.8 >493 >467 >1870<7482 >1 >19.7Warren NaO.sub.2 C CN 0.75 2375 3166DSCG -- -- 1.7 1953 1149This Speci- fication, Examples 3 and 4 ##STR15## CN (Ex. 3) CN (Salt, ex. 4) 0.075 0.075 >1182 >1851<2469 >15,760 >24,680<32,920__________________________________________________________________________
The preceding Table clearly demonstrates the surprising properties of the claimed compounds. The therapeutic index of 1-(4-cyano-phenoxy)-2-hydroxy-3-[2-(5-1H-tetrazolyl)-chromon-5-yloxy]-propane is about 5-times greater than the nearest conger disclosed in Warren, about 15-times greater than DSCG, and from 2.1 to 8.4-times greater than the compounds reported in Augstein. The therapeutic index of the sodium salt of 1-(4-cyano-phenoxy)-2-hydroxy-3-[2-(5-1H-tetrazolyl)-chromon-5-yloxy]-propane is still more superior than any of the prior art compounds.
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1-(4-Cyano-phenoxy)-2-hydroxy-3-[2-(5-1H-tetrazolyl)-chromon-5-yloxy]-propane and its pharmacologically acceptable salts, are useful in the treatment of allergies, allergic asthma and inflammation.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to a cooling device comprising Peltier elements for a thermally highly loaded optical crystal, or laser crystal, respectively, from which laser beams, in particular laser pulses, are obtained, e.g. for the laser crystal of an optical amplifier or oscillator.
2. Description of Related Art
An effective cooling of optical crystals, or laser crystals, respectively, “crystals” in short hereinafter, in laser devices is of particular importance if the crystals, e.g. titanium-sapphire crystals (commonly termed Ti:S laser crystals) are subjected to high thermal loads during operation. This is, e.g., the case if in a passively mode-locked short-pulse laser arrangement (oscillator) the crystal is utilized as an optically non-linear element, and the pump beam and the resonator beam are focussed as highly as possible in the crystal; in doing so, the crystal should have small dimensions and, for compensation thereof, a high dotation so as to keep low the material dispersion, whereby the—specific—thermal load will rise, as has been explained in the earlier application WO-98/10 494-A not previously published. There it has also been explained that cooling to below 10° C. is a problem because of the humidity condensation occurring in that instance, wherein little drops condensed on the crystal may cause the crystal to be damaged rapidly or even to be destroyed.
What is of quite particular importance is, moreover, cooling of the crystal in case of an optical amplifier, as has already been mentioned in Optics Letters Vol. 22, No. 16, Aug. 15, 1997, pp. 1256-1258, “0.2-TW laser system at 1 kHz” by Backus et al. In such an optical post-amplification of oscillator pulses, e.g., also a Ti:S laser crystal is used in which the pulses from the oscillator having an energy of some nJ are amplified to an energy in the order of 1 mJ (i.e., by the factor 10 6 ). To this end, the Ti:S amplifier crystal is “pumped” with green laser light which, e.g., has an average power of 10 to 20 W, which is a multiple of the pumping power at the laser pulse generation in the oscillator. Also by the fact that the optical amplifier is operated in pulses (the pulse frequency being, e.g., approximately 1 kHz), the pumping energy is concentrated to individual pulses which amplify the oscillator pulses. Due to the high powers occurring there, it is important to attain sufficient cooling for the crystal. Insufficient cooling of the crystal will not only result in a poor efficiency, similarly as with the oscillator, but also in an unfavorable beam profile, due to the “thermal lenses” effect which also is explained in the afore-mentioned article by Backus et al. If the crystal is heated, the temperature gradient thus occurring in its material will lead to a refraction index gradient which will unintentionally focus or defocus the laser beam during its passage—depending on the crystal material. Good cooling of the crystal will increase the thermic conductivity of the crystal material, and the temperature coefficient of the refraction index (which causes the “thermal lense” effect) becomes smaller at the low temperatures so that a beam profile approximately corresponding to the ideal Gaussian intensity profile (over the cross-section) will be attained; moreover, the degree of efficacy will be improved. According to the article by Backus et al., liquid nitrogen is used to cool the crystal, which does make it possible to attain extraordinarily low temperatures, by which, however, a practicable embodiment of the optical amplifier is prevented for many purposes of application, in particular for mobile uses.
A somewhat different optical amplifier has been described in the article “Generation of 0.1-TW 5-fs optical pulses at a 1-kHz repetition rate” by S. Sartania et al., Optics letters Vol. 22, No. 20, Oct. 15, 1997, wherein general mention is made that a Peltier cooling device is used for cooling the amplifying crystal. Thus, the problem remains that with an intensive cooling not only condensation water will form on the crystal, but even ice, and that contaminations are present in the air which will deposit on the crystal; in operation, such ice formations and contaminations will lead to a—localized —destruction of the crystal surface by burning in.
SUMMARY OF THE INVENTION
It is an object of the invention to overcome these problems and to provide a cooling device of the initially defined type with which, on the one hand, in spite of a simple construction that will render it particularly suitable for mobile applications, a good cooling in terms of a high degree of efficacy and an optimum beam profile will be achieved, and by which, on the other other hand, a long useful life of the laser crystal will be ensured by avoiding burning in of condensation water (ice), or impurities, respectively.
The inventive cooling device of the initially defined type is characterized in that the crystal, together with the Peltier elements provided for its cooling, is housed in an encasing container, that the interior of the container is evacuated and/or kept dry by means of a desiccating substance, and that the container comprises at least one Brewster window for the passage of the laser beams which is arranged under an angle relative to the optical axis which corresponds to the Brewster angle.
By providing an encasing container it becomes possible to evacuate the container interior or to keep it dry so that condensation water cannot deposit on the optical crystal, or laser crystal, respectively; moreover, defined clean surroundings (vacuum or pure, i.e. contamination-free, dry air) are possible for the crystal. Accordingly, long operating times can be achieved which is a great advantage also with a view to the expenditures required during the installation or during the precise adjustment of optical crystals, or laser crystals, respectively. Moreover, the present cooling device is characterized in that as a consequence of the use of the thermoelectric cooling elements, i.e. Peltier elements, in combination with the encasing container, a compact, simple, handy construction of the laser arrangement is made possible whereby, moreover, its use in vehicles, e.g. also in airplanes, is possible without any problems, since in contrast to cooling with liquid nitrogen, it is not gravity-dependent during its operation. The container may be provided with a tightly closable connection means for an evacuation as well as with tightly sealed electrical line passages for the power supply of the Peltier elements.
With a view to the high intensities occurring in the applications in question, so-called Brewster windows are provided on the container for the passage of the laser beams. In this manner, unintentional reflections can be prevented, i.e. without the broad-band antireflex coatings otherwise used therefor; because such dielectric coatings would not withstand the afore-mentioned high intensities (e.g. peak powers in the MW to GW range at beam diameters of <10 mm and at pulse durations in the 10 fs to ps range, starting from an average power of 10 mW up to the watt range; pump parameters: average power, a few W up to a few 10 W; pump energy, a few mJ; high repetition frequencies in the kHz range which will lead to peak powers in the kM to MW range).
It should be mentioned that with semi-conductor lasers it is known to use encapsulated modules, cf., eg., DE 33 07 933 C, DE 39 22 800 A, JP 1-122 183 A or EP 259 888 A, in which a laser diode element is present in combination with a Peltier element. However, there are no high laser powers and thus also merely low thermal loads on the laser diode elements, and the Peltier elements in fact are merely used for temperature stabilizing purposes. In the known semi-conductor lasers, this is important because in case of laser diodes, the laser wave length depends substantially on the temperature of the semi-conductor chip, and in many instances even its heating is required so as to obtain the correct wave length. Besides, in these known devices, an evacuation of the module or its drying by means of desiccating substances are not mentioned.
With the Peltier elements, in most instances sufficient cooling of the laser crystals can be achieved without any problems, and it has been shown that a temperature difference of approximately 50° C. or 70° C. at the Peltier elements will suffice in most instances. For a particularly pronounced cooling or heat dissipation from the laser crystal it may also be advantageous if the Peltier elements are provided in stacked manner. In this instance, temperatures of −50° C. or −100° C. may easily be reached on the cold side at an ambient temperature (approximately 20° C.) on the warm side. As such, temperature differences at the Peltier elements of up to 130° C., when using conventional Peltier elements, are possible so that cooling may be effected to temperatures of below −100° C.
The optical crystal, or laser crystal, respectively may be platelet-shaped and—with a view to the good cooling attainable—of comparatively small dimensions, and also if used with an amplifier, its dimensions may be merely approximately 3 mm in width and length, with a height of merely 1 to 1.5 mm.
To fix the crystal while ensuring a good thermal transition and a good thermal dissipation, it is also advantageous if the crystal is held between cooling jaws of good thermal conductivity, against which the Peltier elements rest. In doing so, for attaining as large a thermal transition surface as possible as well as a particularly simple retention of the crystal it is, moreover, suitable if the cooling jaws positively embrace and retain the crystal at four sides thereof. A solution which is suitable in terms of production and mounting will moreover be achieved if one of two cooling jaws resting against the crystal at opposites sides thereof has a nose projection extending over the crystal resting on the other cooling jaw, and the cooling jaws are provided with recesses in front of or behind the crystal, respectively, in the direction of the laser beams for the laser beams to pass therethrough.
To keep the Peltier elements on the “warm” side at ambient temperature (or even therebelow), it is furthermore advantageous if the Peltier elements are in engagement with a cooling pedestal on their warm side that faces away from the cooling jaws. For efficiently cooling the warm side of the Peltier elements it has also proven advantageous if the cooling pedestal is liquid-cooled. The cooling pedestal may have the most varying shapes, such as, e.g., cuboid or disk-shaped. To attain a high cold storage capacity as well as for a stable accommodation of the Peltier elements and the cooling jaws and for a simple production it is furthermore suitable if the cooling pedestal is formed by a generally cyllindrical body having a generally V-shaped recess at an end side which accommodates the Peltier elements as well as the cooling jaws with the crystal. For reasons of processing and also for the abutment surface of the Peltier elements and the cooling jaws it is advantageous if the V-shaped recess comprises an apex angle of 90°. To orient the Peltier elements and to facilitate their mounting it is, moreover, advantageous if the generally V-shaped recess defines oblique resting surfaces for the Peltier elements and stops for the Peltier elements are provided at the inner, adjacent ends of the resting surfaces, which stops project upwardly from the resting surfaces.
A particularly simple design of the encapsulated type container which allows for a good sealing, e.g. by means of O-rings, may be obtained if the container comprises a tubular casing closed by a lid. In this connection it is, furthermore, advantageous if the cooling pedestal at its end side facing away from the Peltier elements is provided with a flange with which the tubular casing is tightly connected. It is also advantageous if the cooling pedestal is provided with bores for the passage of cooling liquid in the region of the flange.
For the laser beams to have a low power relative to the area unit of their cross-section, when passing through the window, (so that they will not cause burning in or destruction of the windows after short periods of operation), the laser beams should have as large a cross-section as possible at the site of the windows, i.e. they should be out of focus, which means that for the windows a certain distance should be kept (e.g. approximately 8 to 10 cm) to the crystal—where focussing occurs. To make this possible without enlarging the entire container, it is also suitable if the encasing container, preferably at oppositely arranged sides thereof, is provided with a (respective) projecting, tightly attached pipe socket which, at its outer end, is closed by the window for the passage of the laser beams.
The invention also relates to a laser arrangement comprising a cooling device as explained above.
BRIEF DESCRIPTION OF THE DRAWINGS
In the following, the invention will be explained in more detail by way of a preferred exemplary embodiment illustrated in the drawing to which, however, it shall not be restricted. In detail,
FIG. 1 shows a diagramm of the essential parts of an optical amplifier;
FIG. 2 shows a sectioned top view onto a cooling device for the laser crystal used in such an optical amplifier;
FIG. 3 shows an axial section through this cooling device according to line III—III of FIG. 2;
FIG. 4 shows a top view onto a mounting and cooling pedestal used with this cooling device;
FIG. 5 shows a view of this cooling pedestal in the region of the lower flange part, partially sectioned;
FIG. 6 shows a cross-section through the flange region of this cooling pedestal, according to line VI—VI of FIG. 5;
FIGS. 7A to 7 C show one of the cooling jaws for the laser crystal used with the cooling device according to FIGS. 2 and 3, in a top view (FIG. 7 A), an elevational view ( 7 B) and an end view (FIG. 7 C);
FIGS. 8A to 8 C show the other cooling jaw used with the cooling device according to FIGS. 2 and 3, also in a top view (FIG. 8 A), an elevational view (FIG. 8B) and an end view (FIG. 8 C); and
FIG. 9 shows in a detailed view on an enlarged scale the bracing of the laser crystal between the cooling jaws according to FIGS. 7A to 7 C and 8 A to 8 C with indium foils interposed.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the following, the cooling device according to the invention will be explained in more detail by way of example in combination with an optical amplifier as is schematically shown in its essential parts in FIG. 1; although the cooling device has particular advantages in optical amplifiers because of its efficient cooling effect, it can also be used with other laser arrangements, e.g. with oscillators. Moreover, the materials indicated below for the optical crystal, or laser crystal, respectively (titanium-sapphire crystal) as well as those indicated for the construction of the pump laser (frequency-doubled Nd:YLF-laser neodym-yttrium-lithium-fluoride laser) are to be understood to be an example only.
In FIG. 1, an arrangement of the essential components of an optical amplifier are schematically illustrated, wherein, in the example illustrated, the optical amplifier is illustrated as so-called “multipass-amplifier”, cf. also the afore-mentioned paper by Backus et al., “0.2-TW laser system at 1 kHz”. The invention could, of course, also be employed in other optical amplifiers, i.e. particularly in so-called regenerative amplifiers, where a repeated, colinear passage of the laser beam occurs before the laser beam leaves the amplifier, e.g. by aid of Pockels cells.
In detail, in FIG. 1 a pump laser is schematically shown at 1 , e.g. a frequency-doubled Nd-YLF laser which outputs a laser beam, the so-called pump beam, which is schematically indicated at 2 in FIG. 1 and which supplies the energy for the amplification of laser pulses. At 3 , these laser pulses are supplied by a conventional laser oscillator not illustrated in detail to the amplifier arrangement proper, generally denoted by 4 . The essential element for this amplifier arrangement 4 is an optical crystal, or laser crystal, respectively, 5 , termed crystal in short hereinafter, e.g. a Ti:S crystal, also merely quite schematically shown in FIG. 1, without any cooling device, in which crystal the laser beams are focussed at the various passages indicated by various lines with corresponding arrows. In particular, two focussing mirrors M 1 , M 2 are provided for the amplifying beam at either side of the crystal 5 , wherein at least the focussing mirror M 1 is semitransparent so as to allow the pump beam 2 coming from a focussing lense L 1 to pass to the crystal 5 . Moreover, in FIG. 1 retroreflectors are further shown at R 1 and R 2 for the amplifying beam which provide for the various multipass-positions of the laser beam in space, the retroreflectors R 1 moreover being arranged at a pre-determined distance from each other so that the laser pulses arriving from the oscillator there can enter through the gap thus formed into the amplifying arrangement 4 . Thereafter, an aperture A comprising, e.g., a 4, 6 or 8 hole aperture is arranged in front of the retroreflectors to suppress the laser activity in the amplifier 4 , and a mirror 6 is provided for decoupling the intensified laser pulses. The intensified laser pulses P may, e.g., by supplied to a compressor as is known per se and therefore has not been illustrated in detail, and in this compressor the laser pulses may be shortened in terms of their duration.
For an optical amplification, a pump laser 1 is used which, e.g., generates pulses of a frequency of approximately 1 kHz and with an average power of 10 to 20 W. Since the laser pulses to be amplified arrive from the oscillator at a frequency higher by several orders of magnitude, usually also an arrangement comprising, e.g., Pockels cells is used in combination with the amplifying arrangement 4 so as to suppress non-amplified pulses, which, however, has not been illustrated in detail in FIG. 1 . For further information in this respect, reference may be made to the already mentioned article by Sartania et al., “Generation of 0.1-TW 5-fs optical pulses at a 1-kHz repetition rate”, or to the article by Backus et al., “0.2-TW laser system at 1 kHz”. For a better understanding, it should be mentioned that, e.g., the laser pulses which arrive from the oscillator have a frequency of 75 MHZ, and that only every 75,000th pulse is allowed to pass and is enriched with energy—which comes from the pump laser.
With a view to the high powers which the pump pulses have as well as with a view to the focussing of these pump pulses in a relatively small crystal volume, a correspondingly high heat will develop there so that efficient cooling of the crystal is highly important. Yet with a view to industrial applications of the amplifier or, generally, the laser arrangement, cooling with liquid nitrogen, as in the known arrangement, is not suitable and not handy and, moreover, dependent on gravity so that such a cooling device is not suitable for mobile uses.
A cooling device generally denoted by 7 will now be explained by way of FIGS. 2 to 9 , which cooling device meets the requirements set, such as sufficient cooling, compact, simple, handy construction, independence on gravity etc., and which, moreover, is characterized in that long periods of operation can be achieved for the crystals.
As apparent from FIGS. 2 and 3, the cooling device 7 comprises an enclosure-type, tightly closed container 8 having a tubular casing 9 with end-side flanges 10 , 11 on which a lid 12 and a cooling pedestal 13 are fastened via a flange 13 a by means of screws 14 , additional O ring seals 15 of rubber or elastic plastic being provided between the flanges 10 , 11 , on the one hand, and the lid 12 or the cooling pedestal 13 , on the other hand.
As is particularly apparent from FIGS. 5 and 6, the cooling pedestal 13 comprises four parallel bores 16 for the passage of a cooling liquid, e.g. water, connecting fittings 17 (cf. FIG. 2) being screwed into the ends of the bores 16 which serve for the successive switching of the bores 16 via the ducts or hoses 17 a indicated in FIG. 2 in broken lines. Cooling liquid will, e.g., enter according to arrow E and exit according to arrow A.
The cooling pedestal 13 is made of copper or aluminum, e.g., whereas the lid 12 may, e.g., consist of plastic and the tubular casing 9 , e.g., of aluminum.
From the base of the cooling pedestal 13 , an externally general cylindrical body 19 extends upwardly which serves to accommodate Peltier elements 18 , e.g. the Peltier elements 18 commercially available under the name Melcor Thermoelectrics 2 2 SC 055 045-127-63 and contacts on the inner wall of the tubular casing 9 . In its middle part, the body 19 has a V-shaped recess 20 comprising an apex angle of 90° so that on either side of the center line L (cf. FIG. 2 ), two resting surfaces 21 are defined for the Peltier elements 18 , the inner, adjacent ends of the resting surfaces 21 having upwardly projecting stops 22 , 23 for the Peltier elements 18 . In the exemplary embodiment illustrated, two blocks of Peltier elements 18 are each stacked in superposition on the resting areas 20 . The heat-emitting or “hot” side of the Peltier elements 18 here contacts the two resting surfaces 21 , whereas the heat-accommodating or “cold” side of the Peltier elements 18 contacts two cooling jaws 24 , 25 which fix the Peltier elements 18 in their position, and have a shape which can be seen in FIGS. 7A to 7 C and 8 A to 8 C in detail.
As is particularly apparent from the elevational views according to FIGS. 7B and 8B, the cooling jaws 24 and 25 are generally wedge-shaped with lateral angles of, e.g., 45°, so that they fill the V-shaped recess with the apex angle of 90° of body 19 in their mounted state. The cooling jaw 25 arranged at the right-hand side of the middle line I in FIG. 2 has a nose projection 26 (cf. FIG. 8B) which extends over the cooling jaw 24 arranged to the left of the middle line L and abuts the crystal 5 by its lower side (cf. also FIG. 9 in addition to FIGS. 2 and 3 ), the crystal resting in a stepped recess 27 of the cooling jaw 24 (cf. FIG. 7 B). The crystal 5 has the shape of a parallelepiped with an optical main axis which is oriented in parallel to the center line L, and with end faces which include an angle of, e.g., approximately 60° with the main axis.
From the top view onto the cooling jaw 25 according to FIG. 8A it is apparent that the nose projection 26 resting on the crystal 5 also extends obliquely under an angle of 60°, wherein in continuation of the in FIG. 8A upper edge of the nose projection 26 , the cooling jaw 25 also has a stepped recess 28 with a borderline face which also extends under an angle of 60° to the center line L.
In the same way, the cooling jaw 24 has a stepped recess 29 —also in an imaginary continuation of the nose projection 26 , cf. also FIG. 2 and FIG. 7A, which likewise extends obliquely to the center line L under an angle of 60°.
The depth T 1 of the stepped portion 28 in the cooling jaw 25 and of the stepped portion 29 in the cooling jaw 24 is equal in size, yet larger than the depth T 2 of the stepped portion 27 in the cooling jaw 24 . The height H of the nose projection 26 corresponds to the depth T 2 of the stepped portion 27 , reduced by the thickness of crystal 5 .
Thus, by the stepped recesses 28 , 29 of the cooling jaws 24 , 25 , a clear space is provided for the respective laser beam 2 (cf. FIG. 2) which, via the free-lying end faces of the crystal 5 , can pass into and out of the same.
For the passage of the laser beam 2 , pipe sockets 30 , 31 are mounted to the tubular casing 9 of the container 8 at opposite sides thereof, the outer ends of the pipe sockets being closed by windows 32 , 33 , and the windows 32 , 33 being provided under an angle corresponding to the Brewster angle (e.g. 56°) relative to the main axis of the laser beam 2 so as to exclude reflections.
The somewhat larger cooling jaw 25 has two grooves or milled-in channels 34 , 35 extending in parallel to the center line L which serve to accommodate fastening screws 36 , 37 , the heads of the screws 36 , 37 being arranged to be embedded in long-hole-shaped counterbores 38 , 39 in cooling jaw 25 . The ends of the screws 36 , 37 are screwed into threaded pocket bores 40 in the cooling pedestal 13 (cf. FIG. 2 ).
To evacuate the container 8 , an externally angled pipe connection 41 is provided on the tubular casing 9 . Via a cable passage means also arranged in the tubular casing 9 or via a vacuum-tight connecting plug 42 , power is supplied for the Peltier elements 18 . The evacuation pipe connection 41 may, e.g., be tightly closed after evacuation. If the overall tightness of the capsule-type container 8 cannot be maintained over extended periods of time, with the optical amplifier further in operation, also a pump (not illustrated) attached to the pipe connection 41 may be set into operation several times in between so as to evacuate the container 8 —e.g. to a pressure of a few 10 mbar.
As is apparent from the detailed representation according to FIG. 9, the crystal 5 is embedded between the stepped recesses 28 , 29 and the nose projection 36 , respectively, of the two cooling jaws 24 , 25 via foils 43 , 44 of indium, resulting in a good heat transfer between the crystal 5 and the cooling jaws 24 , 25 .
Instead of an evacuation of the container 8 , equipping of the latter (i.e., mounting of the Peltier elements and the laser crystal) could also be effected in a clean room, whereupon the container 8 is tightly closed by applying a desiccating substance known per se, such as silika gel, e.g. adjacent the cooling jaws 24 , 25 . In this manner, also a deposit of particles and condensation water droplets on the crystal 5 will be prevented.
Furthermore, a modified construction of the cooling device could also consist in mounting the crystal 5 sandwich-like between upper and lower Peltier elements, at whose external, i.e. respective upper or lower sides facing away from the crystal 5 , a respective—e.g. plate-shaped—cooling pedestal abuts.
It is also possible and suitable in many instances to at least monitor, preferably control, the temperature of the crystal 5 in a known manner during operation; for this purpose, a thermosensor (not illustrated) may be inserted in one of the cooling jaws, e.g. 25 , which is connected with a temperature monitoring or controlling circuit. In FIG. 8A, a bore 45 is shown in which such a per se conventional temperature sensor can be inserted.
Although the present invention has been described in relation to particular embodiments thereof, many other variations and modifications and other uses will become apparent to those skilled in the art. It is preferred, therefore, that the present invention be limited not by the specific disclosure herein, but only by the appended claims.
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A cooling device for an optical amplifier or oscillator has Peltier elements enclosed in a housing with an optical crystal and extract heat from the optical crystal. The housing is sealed and can contain a desiccant for removing moisture and preventing particle deposition. Alternately, the housing can be evacuated with a vacuum to maintain a clean operating environment. The housing holds a Brewster window at a Brewster angle with an incident laser beam to permit passage of the laser beam. The housing also can be arranged on a platform providing liquid cooling.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to an adjustable arm for a chair, and more particularly to an adjustable arm having force reduction means whereby the user may vertically adjust the height of the arm easily and effortlessly.
2. Description of the Related Art
Adjustable arms are widely known in the art and range in application from chairs and office seating to vehicle seating. Office seating typically includes multiple adjustment features in order to adapt to the particular task and the particular user. This seating may include vertical seat height adjustment, back height adjustment and the like. Such office chairs may also include spaced arm rests, which have recently included vertical adjustability.
Means for adjustable arms can be found in the art ranging from telescoping tubes and springs to parallelogram action mechanisms to rack and pawl mechanisms to synchronized, simultaneous adjustment. However, these various means may require the user to expend some effort in adjusting the arm as well as engaging it in a desired position. Also, some means require the user to stand in order to adjust the arm rather than to easily adjust the arm rest while being seated.
Consequently, a need exists for an adjustable arm that can be operated easily and effortlessly by the user while remaining seated, as well as providing a range of vertical adjustment.
SUMMARY OF THE INVENTION
In accordance with the present invention, the foregoing deficiencies of prior art are obviated by providing an adjustable arm for a chair and the like comprising an actuator, a locking mechanism and force reduction means mounted on the arm support. The force reduction means interacts with the actuator and the locking mechanism by having a pivot point for translating travel of the actuator to travel of the locking mechanism. The travel of the actuator is greater than the travel of the locking mechanism.
The arm support carries the arm rest on its top, is surrounded by a housing and includes a plurality of vertical slots. The locking mechanism may be spring urged and pivotally mounted inside the housing and may include two ends, one end of the locking lever being capable of engaging with the vertical slots of the arm support and the other end being capable of interacting with the actuator, which may be mounted on the housing. This interaction of the actuator and the locking lever causes the locking lever to become disengaged from one of the slots in order to reposition the adjustable arm rest relative to the chair.
BRIEF DESCRIPTION OF THE DRAWINGS
While the specification concludes with the claims particularly pointing out and distinctly claiming the subject matter of the invention, it is believed the invention will be better understood from the following description, taken in conjunction with the accompanying drawings, wherein:
FIG. 1 is an perspective view of an adjustable arm and the means of attachment;
FIG. 2 is a front elevational view of the force reduction means and the locking mechanism engaged in the rack of the adjustable arm;
FIG. 3 is front elevational view of the force reduction means and the locking mechanism of the adjustable arm;
FIG. 4 is a perspective view of the force reduction means and a portion of the locking mechanism of the adjustable arm;
FIG. 5 is an exploded perspective view of the force reduction means and a portion of the locking mechanism of the adjustable arm;
FIG. 6 is sectional view of adjustable arm taken along the line 6--6 of FIG. 2;
FIG. 7 is an enlargement of the sectional view of the adjustable arm taken along the line 6--6 of FIG. 2 illustrating the operation of the adjustable arm;
FIG. 8 is a front elevational view of the adjustable arm housing with a cut-away view of the rack and the indexer of the adjustable arm;
FIG. 9 is a front elevational view of the locking mechanism of the adjustable arm including the indexer; and
FIG. 10 is a sectional view of the indexer of the adjustable arm taken along the line 10--10 of FIG. 9.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The invention herein described provides an adjustable arm for a chair or the like having an actuator, a locking mechanism and force reduction means which enable a user to adjust the arm rest relative to a chair in a plurality of vertical positions easily and effortlessly while remaining seated.
Referring now in detail to the drawings wherein like reference characters represent like parts throughout the several views, there is illustrated in FIG. 1 an adjustable arm 10 which includes a shroud or housing 12, which may be made of metal or plastic. The housing 12 extends upwardly to include an upper portion 13 whereupon an arm rest 14 is attached. The upper portion 13 of the housing 12 and the armrest 14 are shown in phantom for reasons of clarity. An arm support 16 extends downwardly to form a bracket 18 with which to attach the arm 10 to the underside of a chair. The housing 12 surrounds the arm support 16 so as to conceal the inner workings of the adjustable arm 10, which will be described presently, while being able to be moved freely up and down along the arm support 16 by way of a bearing sleeve 17, which is slipped over the arm support 16, as the arm 10 is adjusted to various vertical heights.
The upper portion 13 of the housing 12 is hollow and contains a recess 15, which is illustrated in FIG. 2, wherein the inner workings of the adjustable arm 10 are placed. FIG. 1 illustrates a portion of the inner workings contained inside the housing 12. A metal plate 20 is attached to the upper portion 13 of the housing 12 with screws, not shown, which extend through apertures 21. The metal plate 20 includes a slot 22 through which a tongue member 24 extends. The tongue member, or the second lever 24, comprises the force reduction means and will be more fully described presently. An actuator or pushbutton 26 is located on the side of the metal housing 12 and extends through the housing 12. An indicator window 28 may be located on the housing 12 to indicate to the user in which of the various vertical positions the adjustable arm is located.
FIG. 2 illustrates a front elevational view with the front of the housing 12 removed in order to expose the inner workings of the adjustable arm 10. The inner workings of the adjustable arm 10 include force reduction means and a locking mechanism. FIGS. 3, 4 and 5 illustrate several views of the force reduction means as well as a portion of the locking mechanism.
FIG. 2 further illustrates the inner workings of the adjustable arm 10 engaged in one of a plurality of grooves 33 of a rack 34. The rack 34 is one of the elements comprising the locking mechanism, which will be described presently, and is contained in the arm support 16 as a means of locating and locking the adjustable arm in one of a plurality of vertical positions. The number of grooves 33 comprising the rack 34 represents the number of vertical positions available in which to adjust the chair arm 10. The rack 34 may also include side grooves 35 which are located perpendicularly to the grooves 33 and serve as a means of producing a "clicking" noise to audibly indicate a change in the positioning of the arm 10 to the user.
The force reduction means, most clearly illustrated in FIG. 5, includes a first lever hereafter referred to as a flipper mechanism 36 and a second lever hereafter referred to as a tongue member 24. The tongue member 24 comprises a metal, T-shaped tab with wing-like extensions 37 along the top 38 of the tongue member 24 and includes a straight portion 40 and an offset portion 41 interconnected by an angled portion 43.
The flipper mechanism 36 includes a first, or top, end 42 and a second, or bottom, end 44. The first end 42 of the flipper mechanism 36 includes a planar portion 46, the top of which forms a ledge 48 that interacts with the straight portion 40 of the tongue member 24. The second end 44 of the flipper mechanism 36 includes a planar portion 50 having two extensions 51 on either side 52. Each extension 51 has an aperture therethrough at 70. The planar portion 50 also includes a front face 53 which contains an opening 54 whereby a leaf spring 56 is secured to the front face 53 by a rivet 58. The back face 60 of the planar portion 50 terminates in an L-shaped ledge or latch member 62 which coacts with the grooves 33 in the rack 34 in order to lock the arm 10 in a desired position.
Still referring to FIG. 5, a C-shaped yoke member 64, which is welded to the bottom of the metal plate 20, extends downwardly and is connected to the flipper mechanism 36 by a hinge pin 66 thereby creating a pivot point on which the flipper mechanism 36 rotates. The yoke member 64 includes a front end 67 which rests against the interior of the front of the housing 12 and two downwardly projecting extensions 68. Each extension 68 contains an aperture 69 which overlaps with the aperture 70 in each of the two extensions 51 of the second end 44 of the flipper mechanism 36. The downwardly projecting extensions 68 of the yoke member 64 fit snugly overtop the side extensions 51 of the flipper mechanism 36 so that the apertures 69 and 70 are aligned to receive the hinge pin 66 thereby connecting the yoke member 66 to the flipper mechanism 36 and creating a pivot point on which the second end 44 of the flipper mechanism 36 rotates.
FIGS. 8, 9, and 10 illustrate several views of an indexer 72 which may be located on the inside of the front of the housing 12 and includes a cam 74 and spring 76. The cam 74 is mounted for rotation about a pin 75 which may be mounted to the inside of the front of the housing 12 and includes a hook-like projection 78 by which one end 80 of the spring 76 is attached. The other end 82 of the spring 76 is attached to the inside of the housing 12 by a small rivet 84. The cam 74 further includes a tooth 86 which extends from one side near the bottom 88 of the cam 74 and interacts with the side grooves 35 of the rack 34 to produce a "clicking" noise to audibly indicate a change in position of the arm rest 14 as the housing 12 is moved upwardly or downwardly along the arm support 16.
Each element and its cooperation relative to each other will now be described in order to understand the operation of the adjustable arm. The tongue member 24 is inserted into the slot 22 in the metal plate 20 and extends downwardly. The wing-like extensions 37 located along the top 38 of the tongue member 24 hold the tongue member 24 in place and define a pivot point for the tongue member 24 which swings freely but does not fall through the slot 22. The straight portion 40 of the tongue member 24 coacts with the first end 42 of the flipper mechanism 36 in such a way that the ledge 48 abuts the straight portion 40 of the tongue member 24. The offset portion 41 of the tongue member 24 is disposed adjacent the conical tip of the pushbutton 26.
FIGS. 6 and 7 best illustrate the actual operation of the adjustable arm 10. The user depresses the pushbutton 26 which moves the offset portion 41 of the tongue member 24 a predetermined distance. The pushbutton 26 has a conically shaped tip for constant concentrated contact with the tongue member 24. This actuation of the pushbutton 26 and the tongue member 24 causes the tongue member 24 to act against the first end 42 of the flipper mechanism 36 with a force that has been enhanced by the differences in the distance from the tongue member 24 pivot point. This force pivots the second end 44 of the flipper mechanism against the leaf spring 56 which is restrained by the interior of the front of the housing 12. This movement causes the latch member 62 located at the back face 60 of the second end 44 of the flipper mechanism 36 to become disengaged from one of the plurality of grooves 33 of the rack 34 thereby enabling the arm rest 14 and the associated housing 12 to be adjusted vertically to another desired position easily and effortlessly by way of the bearing sleeve 17, which by its construction, produces a low coefficient of friction, thereby obviating the need for ball bearings and the like. Once the desired position is reached, as can be evidenced by the "clicking" noise of the indexer 72 tooth 86 grating along the side grooves 35 of the rack 34, the user releases the pushbutton 26. This results in the urging back of the latch member 62 into a new groove 33 of the rack 34 by the leaf spring 56. Thus, the arm is locked into a new vertical position and remains stationary until a different vertical position is desired.
A user can vertically adjust the arm rest of the chair while seated by gripping the arm rest and depressing the pushbutton with his or her thumb. This depressing of the pushbutton is the only effort that need be expended by the user. The force reduction means which includes the tongue member and the first end of the flipper mechanism translates the small force expended by the user into a greater force which causes the latch member to become disengaged from the rack, thereby enabling the user to easily move the arm rest and associated housing upwardly or downwardly to a different position. Thus, the invention provides for a means of adjusting an arm rest easily and effortlessly by a user while remaining seated.
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An adjustable arm for a chair and the like whereby the arm may be adjusted vertically within a plurality of incrementally spaced positions. The adjustable arm includes an actuator, a locking lever and a second lever located and mounted between the actuator and the locking lever. The second lever interacts with the actuator and the locking lever and has a pivot point for translating travel of the actuator to travel of the locking lever with ease and a minimum of effort on the part the user. The first lever includes a latch that coacts with predeterminately spaced grooves of a rack, thereby enabling the user to lock the arm into one of various vertical positions, easily and effortlessly.
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CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional Application No. 60/904,932 filed Mar. 5, 2007.
BACKGROUND OF THE INVENTION
[0002] The present invention is directed to a holder for skewers of the type used in preparing shish kabob and related food's on a grill.
[0003] The term shish kabob generally refers to both a method and a food type wherein meats and/or vegetables are skewered in side by side fashion on a relatively thin skewer and then placed on a barbeque grill or the like for cooking. There are some other related food preparation techniques that use skewers in a similar manner.
[0004] An inherent problem with preparing shish kabob is that the food is seldom skewered through the center of gravity of each piece, such that on one side of the skewer each piece of food is usually heavier than the other side. The food is also often slippery or becomes that way during cooking. Consequently, when the skewer is rotated to cook the food on an opposite side, the food often partially or totally rotates on the skewer, so that additional tools or utensils such as tongs or spatulas must be used to try to rotate the food and this often works poorly.
[0005] Furthermore, the skewers are frequently constructed of strips of bamboo with sharpened ends. When used on a grill, bamboo skewers of this type tend to burn at the ends and can become very hot. A user can therefore become burned by the skewer in trying to rotate or reposition the food or remove the food from the grill if the user touches the ends with their skin. While metal skewers are available and do not burn, such have relatively high heat capacity and store substantial heat so that they can also burn a user who tries to pick up the skewer by the ends with the user's fingers and are more expensive than the bamboo.
[0006] While prior art has attempted to resolve some of the problems for example by placing the skewers in a rack or by having expensive holders with sliding removal apparatus, such devices are comparatively expensive and do not function with simple bamboo skewers and the like. Because grocery stores are now preparing shish kabob and do not want to include expensive skewers with the food that would substantially increase the cost of the product, it is desirable to find a system that functions well with conventional bamboo skewers, but can use other types of skewers also.
[0007] Therefore, a device was found to be needed that would function with simple conventional skewers, would prevent the food from rotating relative to the skewers and which would allow a user to pick up the skewers by hand while on the grill for rotation or removal without the user becoming burnt. Finally, it is preferred that such a device also control multiple skewers so that skewers could be used in pairs and that multiple skewers can be handled by the same device.
SUMMARY OF THE INVENTION
[0008] A handle for preferably holding a plurality of skewers, especially in multiple skewer pairs. The handle is also preferably used in pairs so as to be positioned at opposite ends of the skewers.
[0009] Each handle includes a body with a series of parallel and spaced bores on one side thereof. The bores have a progressively narrowing or step down diameter, so as to allow the bores to snugly receive skewers of different diameter. The bores are positioned to hold pairs of skewers wherein each skewer of a pair passes through the same food items in parallel but spaced relationship to each other to prevent rotation of the food about a single skewer.
[0010] The handle also has a central axis parallel to the bores and a turning knob that extends coaxially with the axis and opposite the skewer openings for the bores. The knob is comparatively thin and includes axial aligned outer ridges to help a user grip the knob.
[0011] The entire handle is preferably constructed of a low heat capacity material and especially a US Federal Drug Administration approved silicone having a durometer shore A value of from 70-80 and a degradation temperature of about 506° Fahrenheit. Each handle transfers little heat to a user upon touching and thereby allows a user to both rotate the food and remove it form the grill by grasping the handle. The knob facilitates rotation of the food while at the grill. Ribs are provided on grasping knobs for the handles to reduce the surface area of the handle device that directly touches the user, thereby reducing heat transfer. Each handle preferably holds two skewers, such that food is loaded onto both skewers at the same time, so as to more easily maintain a parallel orientation of the skewers and skewered region of the food.
[0012] In certain embodiments a shield is provided to divert heat from the grasping knob. The shield can be hemispherical in shape or partially hemispherical to allow for easier grasping.
[0013] The handles allow a user to turn, rotate, flip or remove the food from the grill or other heating surface by allowing contact of limited duration without burning or overheating the skin of the user.
OBJECTS AND ADVANTAGES OF THE INVENTION
[0014] Therefore, the objects of the present invention are: to provide a holder for use in conjunction with skewers on a grill or other cooking surface that have low heat capacity and allow a user to pick up the holder from the grill by hand without the holder burning the user; to provide such handles that are constructed of silicone; to provide such a holder used in pairs to receive opposite ends of skewers; to provide such a holder having a plurality of bores with each bore being parallel to other and adapted to receive a single skewer such that pairs of skewers can be inserted though a single group of food pieces and then joined at apposite ends to such handles; to provide such handles having bores that are tapered so as to be adapted to receive skewers of different diameters; to provide such a handle having a turning knob extending coaxially relative to the handle and from an opposite side of the handle that receives the skewers; to provide a handle that incorporates a shield to deflect heat from the grasping knob so as to make it cooler to the touch when removing the kabob from the grill; to provide such a handle that can be adapted to receive multiple pairs of skewers; and to provide such handles that are comparatively easy and inexpensive to make and that are especially will suited for the intended use thereof.
[0015] Other objects and advantages of this invention will become apparent from the following description taken in conjunction with the accompanying drawings wherein are set forth, by way of illustration and example, certain embodiments of this invention.
[0016] The drawings constitute a part of this specification and include exemplary embodiments of the present invention and illustrate various objects and features thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] FIG. 1 is perspective view of a double skewered shish kabob with handles at each end thereof according to the present invention and illustrating the positioning of the shish kabob on a grill and a user's hands rotating the shish kabob using knobs on the holders.
[0018] FIG. 2 is an enlarged and fragmentary side elevational view showing the shish kabob on a grill with one handle.
[0019] FIG. 3 is a top plan view of the handle.
[0020] FIG. 4 is a front view of the handle.
[0021] FIG. 5 is a cross-sectional view of the handle, taken along line 5 - 5 of FIG. 4 .
[0022] FIG. 6 is a rear view of the handle.
[0023] FIG. 7 is a cross-sectional view of the handle similar to FIG. 5 demonstrating the ability of the handle to receive skewers of different diameters.
[0024] FIG. 8 is a perspective view of a modified handle according to the present inventions.
[0025] FIG. 9 is a front elevational view of the modified handle.
[0026] FIG. 10 is a top plan view of the modified handles.
[0027] FIG. 11 is a side view of the modified handle.
[0028] FIG. 12 is a cross-sectional view of the modified handle, taken along line 12 - 12 of FIG. 11 , showing two pairs of skewers about to be inserted into the handle.
[0029] FIG. 13 is a bottom plan view of a second modified handle in accordance with the invention.
[0030] FIG. 14 is a side elevational view of the second modified handle.
[0031] FIG. 15 is a bottom plan view of a third modified handle in accordance with the invention.
[0032] FIG. 16 is a side elevational view of the third modified handle.
DETAILED DESCRIPTION OF THE INVENTION
[0033] As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention, which may be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present invention in virtually any appropriately detailed structure.
[0034] A pair of holders or handles 1 are provided for receiving multiple skewers 2 for cooking shish kabob 4 on a grill 5 . The handles 1 are manipulated by fingers 7 of a user's hands 8 .
[0035] As shown in FIGS. 1 and 2 , a pair of skewers 2 of the type constructed of bamboo, metal or other suitable material are inserted through various food items such as meat pieces 10 and/or vegetable pieces 11 of the shish kabob 4 . The skewers 2 are parallel to one another and may have pointed or flat ends 13 . The skewers 2 have a specific diameter and skewers in general having standard size diameters may be used in accordance with the invention. For example, FIG. 7 shows skewers 15 , 16 and 17 of different diameter.
[0036] Each handle 1 has a body 20 that is generally rectangular, as seen in FIG. 3 , with the sides 26 and 27 pinched inwardly slightly. Each handle 1 is wider than thick and is sized and shaped to be spaced from the grill 5 during use by the food pieces 10 and 11 , as is seen in FIG. 2 .
[0037] Located at a front side 29 of each handle 1 are a pair of spaced openings 22 from which parallel and spaced bores 23 extend into the body 20 . Each bore 23 has first, second and third regions 25 , 26 and 27 of decreasing diameter and each region 25 , 26 and 27 is sized and shaped to snugly a respective skewer 15 , 16 and 17 .
[0038] Located on the rear side 30 of the body 20 opposite the openings 22 is a knob 28 . The knob 28 is generally cylindrical and has an axis of rotation A that is coaxial with the axis of rotation of the body 20 . The knob 28 is sized and shaped to be grasped by a user's fingers 7 , as seen in FIG. 1 and rotated. The knob 28 has a series of ribs 31 to facilitate grasping. The ribs 31 provide discontinuous engagement of the knob 28 with the skin of the user, as compared to the entire radial outer surface of the knob 28 , so that there is reduced heat transfer to the fingers of the user than if the user grasped the knob 28 without the ribs 31 .
[0039] Each holder 1 is constructed of a low heat capacity and retention material, preferably a silicone. The material of construction is especially a silicone that does not experience heat degradation below about 506° Fahrenheit and has a durometer of Shore A about between 70 and 80.
[0040] In use pairs of skewers 2 are inserted through food pieces or chunks 10 and 11 in spaced but parallel relationship to each other. Skewer ends 13 are inserted in respective bores 23 in opposite handles 1 and pushed until snugly seated by friction or restriction with the bores 23 forming a shish kabob assembly 35 . Most skewers 2 are of the type having a sharp end and a dull or unsharpened end. Normally, the skewers are first both loaded into one handle 1 by the unsharpened end. This way food can be loaded onto the sharpened ends simultaneously and with proper spacing. The shish kabob 4 assembly 35 is then placed on the grill 5 . When one side of the shish kabob 4 is cooked, the user or cooker grasps the knobs 28 using the user's fingers 7 and rotates the shish kabob 4 to a second side thereof. When fully cooked, the user again grasps the knobs 28 of opposite handles 1 and takes the shish kabob 4 from the grill 5 . The bores 23 preferably pass entirely through each holder 1 to allow for easier cleaning and sanitation.
[0041] A modified handle 100 is shown in FIGS. 8 through 12 . The handle 100 is similar in many ways to handle 1 and only portions that are different are discussed here.
[0042] The handle 100 has a body 102 that is generally semicircular when viewed from the top, as seen in FIG. 10 , with a height that is substantially less than the width thereof.
[0043] Extending inwardly from a body front side 103 are six parallel and spaced bores 104 . The bores 104 each have step down regions 105 , 106 and 107 similar to handle 1 . Extending from a body rear side 110 opposited side 103 is a turning knob 111 . The knob 111 is generally cylindrical with axial extending and grip improving ribs 112 . The knob 111 is coaxial along Axis B with the body. Two fragmentary pairs of skewers 115 are shown in FIG. 12 just prior to insertion into the far left and right pairs of bores 104 . In this manner two different arrangements of shish kabob can be cooked on the pairs of skewers 115 in side by side relationship.
[0044] Illustrated in FIGS. 12 and 13 is a skewer handle generally identified by the reference numeral 300 . The handle 300 has certain elements and structure in common with the handle 1 and reference is made to the description of the handle 1 for additional detail.
[0045] The handle 300 includes a generally rectangular body 302 with a rearward projecting grasping knob 303 and a pair of front to rear pass through skewer receiving bores 305 and 306 .
[0046] Projecting rearward from the body 302 and about the knob 303 is a shield 310 . The shield 310 has a truncated hemispherical shape wherein side portions of a hemisphere are removed. The shield 310 is relatively thin and surrounds the knob 303 , but is spaced sufficiently far to allow finger access to the knob 303 . Shield top and bottom portions 311 and 312 are aligned to be located between the fire and the knob 303 during use, whether the handle 300 is bottom side down or top side down when the skewers are turned over. The open spaces on the sides between the top and bottom portions 311 and 312 allow finger access to the knob 303 . It is foreseen that this shield could be parabolic or U-shaped in cross section or a thin semi cylindrical shell.
[0047] Illustrated in FIGS. 14 and 15 is a skewer handle generally identified by the reference numeral 400 . The handle 400 has certain structure detail in common with the handle 1 and reference is made to the description of the handle 1 for additional detail.
[0048] The handle 400 includes a body 402 with a rearward projecting grasping knob 403 and a pair of skewer receiving bores 405 and 406 .
[0049] The handle 400 includes a shield 410 that extends rearward from the body 402 so as to generally surround the knob 403 except to the rear. The shield 410 is in the form of a thin hemispherical shell that is centrally secured to the body 402 at the frontward end of the grasping knob 403 . The shield 410 is sufficiently spaced from the rearward end of the knob 403 to allow a user to insert fingers between the knob 403 and shield 410 to grasp the knob 403 . The shield 410 deflects at least some heat that would otherwise transfer by radiation to the knob 403 during cooking, thereby making the knob 403 more comfortable to pick up by the user.
[0050] While the devices of the present application are especially useful in conjunction with shish kabob as described, it is foreseen that such may be used for cooking other similar or similarly cooked foods on a grill or other heated surface.
[0051] As used herein the terms handle and holder are understood to especially mean structure that allows a user a place to grasp to manipulate cooking food, such as shish kabob and to flip, turn or rotate the food on the cooking surface or to quickly place the food, after cooking, on a plate, tray or other carrier. While a user may hold the device for a longer time, normally the contact between the handle or holder and the skin of the user would be short.
[0052] It is to be understood that while certain forms of the present invention have been illustrated and described herein, it is not to be limited to the specific forms or arrangement of parts described and shown.
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A holder for shish kabob skewers having a body and a plurality of bores in one side thereof sized and shaped to simultaneously receive at least two spaced skewers. Each holder also having a knob for grasping and rotating the holder. Preferably, a heat shield at least partially surrounds the grasping knob. The bores being have separate regions adapted to receive skewers of different sizes. The holders being constructed of a low heat retention material, especially silicone to facilitate direct pick up from a grill by a user.
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CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation-in-part application of a prior application Ser. No. 10/230,357 filed on Aug. 28, 2002 entitled “Load Carrier for Vehicle”, which is incorporated by reference.
FIELD OF THE INVENTION
[0002] This invention relates generally to load carriers for use at the rear of a vehicle, and deals more particularly with a bumper assembly and load carrying device adapted for mounting to the vehicle by a unique carrying beam.
BACKGROUND OF THE INVENTION
[0003] The present invention, is intended for use with a present day automobile of the type having a conventional rear bumper which includes a decorative shock absorbing cover as well as a structural support member to which the cover is mounted. Such a structural bumper support is generally mounted to spaced attachment pads on the vehicle body. The present invention calls for substituting a unique load carrying beam for the structural support so as to provide a spaced support lands constructed and arranged to fit the spaced attachment pads in the vehicle body. The conventional bumper components, in the form of the decorative shock absorbing cover and the underlying structural support, are remounted to the vehicle after mounting the beam to the said attachment pads of the vehicle.
[0004] The above mentioned beam is provided with at least two rearwardly open sockets that are arranged in spaced vertical relationship to the support lands. The sockets are further provided inwardly of these lands so as to be spaced apart approximately half the horizontal distance between the vehicle attachment pads.
[0005] A typical load carrying device in the form of a bicycle rack for example, comprises a frame which is fitted with a slide bolt adapted to be received in one of the sockets, and to be locked in place by angular rotation of the frame relative to the socket. The socket is fixed relative to the vehicle as described above. When the frame or bicycle rack is rotated into position, a second slide bolt provided in a second portion of the frame, is aligned with the second of the two sockets to be slid into place into the second socket defining structure so as to anchor the frame to the vehicle.
[0006] Other frames can be configured for supporting other loads, such as skis, snowboards, and other personal sports related equipment.
[0007] A conventional trailer hitch is also provided as the load carrying device, in which case a trailer of conventional geometry can be secured to a load carrying device by providing a conventional trailer hitch ball for example, on a frame secured to the vehicle by the two slide bolts in the frame structure designed along the lines of the above-described bicycle rack frame.
[0008] Other variations of load carrying device frames are within the scope of the present invention as well. For example, a platform suitable for use as a table might be provided as the frame. Alternatively, a storage box can be provided on such a table or on its own frame as adapted for supporting such a storage box. Still further possibilities for the frame configuration are apparent to those of ordinary skill in the art to accommodate to fit particular sports related or recreational related activities.
DESCRIPTION OF THE DRAWINGS
[0009] [0009]FIG. 1 shows an automobile or vehicle of the type having laterally spaced attachment pads for receiving a bumper support or crash bar, which support is typically fitted with means for attaching a decorative shock absorbent bumper cover. Such a cover is shown in FIG. 5. A structural support adapted to hold such a bumper cover is depicted in FIG. 4.
[0010] [0010]FIG. 2 shows a beam constructed in accordance with the present invention, such beam having spaced lands constructed and arranged so as to fit the spaced attachment pads in the vehicle body. The beam of FIG. 2 further includes at least two rearwardly opened sockets arranged below the lands and spaced inwardly thereof.
[0011] [0011]FIG. 3 shows the beam of FIG. 2 installed on the vehicle.
[0012] [0012]FIG. 4 shows the bumper support provided on the vehicle, and more particularly on the beam illustrated in FIGS. 2 and 3.
[0013] [0013]FIG. 5 shows the vehicle after reattachment of the bumper cover, the only part of the beam of the present invention, which is visible being the rearwardly opened sockets.
[0014] [0014]FIG. 6 is a perspective view showing a frame in exploded relationship to a carrier beam with the two slide bolts or pins for securing these components. The frame has a conventional ball socket for receiving a conventional trailer and is shown in an initial broken line position for insertion of the primary slide bolt.
[0015] [0015]FIG. 7 is a perspective view of another frame, for use in carrying bicycles or skis for example, being assembled with the carrier beam socket as in the previous view.
[0016] [0016]FIG. 8 shows a trailer such as that referred to with reference to FIG. 6.
[0017] [0017]FIG. 9 shows a bicycle rack such as that referred to with reference to FIG. 7.
[0018] [0018]FIG. 10 shows a ski rack such as that referred to with reference to FIG. 7.
[0019] [0019]FIG. 11 shows a support platform or table such as that described below with reference to FIG. 6.
[0020] [0020]FIG. 12 is similar to FIG. 11 but shows a storage box on the platform.
[0021] [0021]FIG. 13 shows in detail the cam slots defined in the primary pin or slide bolt of FIGS. 6 and 7.
[0022] [0022]FIG. 14 is a perspective view of the secondary slide bolt shown in FIG. 6 at 20 .
DETAILED DESCRIPTION
[0023] Turning now to the drawings in greater detail, and referring particularly to FIG. 2, a beam 10 is shown having spaced apart lands 10 A , 10 A which lands are so constructed and arranged as to fit the spaced attachment pads in the vehicle body to which the device of the present invention is to be attached. FIG. 3 shows four threaded bolts securing each of these lands to the vehicle body.
[0024] The beam 10 has in addition to the lands 10 A , 10 A rearwardly the open sockets 10 B , 10 B arranged below and affect laterally from the lands. These sockets are spaced apart horizontally by a distance of approximately one-half the lateral spacing between the lands. Preferably, this spacing is in the range between one-half the springs T between the lands (T/2) spacing T and one-fourth that value (T/4).
[0025] As mentioned previously, the vehicle bumper is conventional, and has a decorative crash absorbing plastic cover portion, which is removable as suggested in FIG. 4, and which is supported by an underlying crash bar or structural sport member 12 . This member 12 , as shown in FIG. 4, can be mounted onto the lands of the beam 10 as shown in FIG. 4 so as to allow the decorative rear bumper of the vehicle to be resecured to the vehicle once the beam has been mounted to the vehicle.
[0026] In accordance with the method of the present invention the crash bar support portion of the bumper as well as the plastic decorative cover portion thereof are removed as suggested in FIG. 1. The beam 10 of the present invention is then secured to the vehicle as described above, and as best shown in FIG. 3. The vehicle also includes structural members conventionally formed in the basic “unibody” construction. These structural members are provided by the manufacturer behind the attachment pads shown in FIG. 1. Further structural members can be seen in the vehicle as suggested by the square cross sectional members which are rearwardly open and extend from the underside of the vehicle as best shown in FIG. 1. These further members are utilized in the preferred embodiment shown in the drawings by providing bars 10 c projecting oppositely to the rearwardly open socket defining portions of beam 10 . Thus, in the preferred embodiment, advantage is taken of the structurally secure portions of the vehicles unibody construction. The purpose of the beam 10 is to provide a link between the vehicle and a load carrying device to be described. Such a load carrying device may comprise a ski rack, a bicycle rack, a luggage carrier or a platform for a storage box that also serves as a table. A trailer can also be accommodated with a frame of appropriate configuration (see FIG. 6).
[0027] In further accordance with the present invention, the plastic bumper cover is reattached as shown in FIG. 5 to the structural support or crash bar shown in FIG. 4.
[0028] [0028]FIGS. 6 and 7 illustrate the complementary slide bolt and receptive socket configuration used to couple the load carrying device or devices to the above-described support beam 10 . Basically, a frame structure is provided that is dictated by the particular load to be carried, and in FIG. 6 a trailer hitch ball 14 is shown mounted on a frame which preferably takes the form of plate 16 that is secured to a primary slide bolt or pin 18 so that the frame or plate 16 can be oriented in the vertical position shown in broken lines in FIG. 6, allowing the slide bolt 18 to be inserted in the socket 10 B . The slide bolt 18 is preferably provided with a cam slot that cooperates with one or more pins inside the socket 10 B , so the rotation of the frame from the vertical broken line position shown to the solid line position shown will lock these components in assembled relationship to one another. Further, and in order to assure that the plate 16 remains horizontal when so assembled, a secondary pin 20 is provided in a socket portion 16 B in the frame 16 so as to be received in the opposite socket 10 B in the beam 10 . This pin 20 also rotates so as to lock the pin 20 and hence the frame 16 in position relative to the support beam 10 .
[0029] [0029]FIG. 7 shows a similar arrangement, but the frame 16 ′ is preferably in the form of an A-frame with angularity related legs 16 ′ A and 16 ′ B . Here again, the primary slide bolt or pin 18 is mounted in the lower end of the leg 16 ′ A and the entire frame 16 ′ can be rotated through 90° or something less than 90° to lock the primary pin 18 in place. A secondary pin 20 is inserted in an opening 16 ′ C so as to secure the frame 16 in assembled relationship to the carrier beam 10 .
[0030] [0030]FIGS. 8 and 9 show respectively, and admittedly in somewhat schematic fashion, the load to be carried by the frames illustrated in FIGS. 6 and 7 respectively.
[0031] [0031]FIG. 14 shows the slide bolt 20 of FIG. 6 in greater detail, and illustrates the single cam slot required in this “separable” coupling component. Only one pin need be provided in its socket of the bar or beam 10 . This bolt 20 received in an opening or bore provided for it in the frame 16 , 16 and is also received in that socket. Rotation of this slide bolt is facilitated by a handle 21 . A tee shaped handle, or other shaped knob can be provided in lieu of the handle 21 shown
[0032] Other variations will be apparent from the preferred embodiment described above. For example, the auto manufacturer (OEM) may build the vehicle wit the beam 10 installed as original equipment. The OEM bumper support described above, and shown prior to its removal in FIG. 4, can be omitted altogether. The external bumper cover would be installed directly on beam 10 , by the OEM rather than installed on such a support as an after-market installation in the manner described, and shown in FIGS. 1 - 4 .
[0033] Another variation is to provide two primary bolts rather than one as shown in FIG. 14. In place of the secondary bolt 20 , the frame would have both socket openings such as shown at 16 a in FIG. 6 to receive both slide bolts at the same time. Lock pins would be required to secure both primary slide bolts in place in a manner similar to that now used in conventional receivers. The more conventional square or non-round sockets would then provide additional structural strength and rigidity for any load to be carried on a frame fitted with such a twin receiver geometry.
[0034] In accordance with the present invention other frames can be adapted for carrying loads of varieties similar to the trailer and bicycle load described above. For example, frames with the same primary and secondary pin configurations described above can be devised for loads of different types; including tables, storage boxes, fishing pole holders, skis and snowboards, and even such recreational equipment as umbrellas and tables. In summary, the present invention has two aspects, one the mounting of the support beam to the vehicle unibody pads that are also used to support the bumper, and in its second aspect comprises a frame selected from a plurality of unique frame. Each frame has at least one primary slide bolt or pin, and a secondary slide bolt or pin movably mounted in that frame such that the frame can be secured by the slide bolts to the beam.
[0035] In light of the above, it is to be understood that within the scope of the appended claims, the invention may be practiced otherwise and as specifically described.
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A unibody style automobile has bumper attachment pads for a crash bar and bumper cover assembly of conventional configuration. Removal of these bumper components provides access to these pads for a load carrier or beam that defines two coupling connections for a frame selected from a plurality of frames, each designed for a different load. All the frames have one fixed slide bolt received in one of the two sockets in the beam. A second bolt provides a very secure attachment point for each of these frames.
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FIELD OF THE INVENTION
This invention relates to the construction of a header pipe for a coolant condenser used in automobile air conditioners.
PRIOR ART
The conventional coolant condenser of an air conditioner has the construction as shown in FIG. 11 and the function as shown in FIG. 12. Coolant is supplied from a left header pipe A, through an upper set of three tubes B to right header pipe C, from which it flows through an intermediate set of three tubes B to be returned to header pipe A. Then it is led from header pipe A through a lower set of three tubes B to header pipe C from which it exits. The coolant flows in a meandering or sinuous fashion through header pipe A, a plurality of tubes B, and header pipe C, and is pressurized for forced heat radiation to reduce it to low-temperature high pressure liquid coolant. Heat radiated at this time is transmitted to tubes B and thence to corrugated fins D provided between adjacent tubes B to be dissipated through air supplied thereto.
The header pipes A and C have the same structure and, as shown in FIGS. 11 and 12, are partitioned in the longitudinal direction by partitioning plates E. The header pipes A and C each have a plurality of radially elongate tube slots F formed by a press or stamping operation for receiving tubes B. Tubes B, when inserted, are secured by soldering K to the walls of slots F such that coolant will not leak. Tubes B are also soldered to the corrugated fins D.
When the tube slots F are formed by a stamping operation without the steps of inserting cores in the header pipes A and C, the edges X of slots F are convexedly turned and the pipe headers are deformed, making it difficult to insert tubes B through slots F. To avoid this in practice a core G having punch holes dimensioned to the size of the slot is axially inserted into the header pipe A and the press operation carried out after aligning the escapement hole H formed in core G and punch J (See FIGS. 15-17).
Meanwhile, in order to facilitate insertion of tubes B into tube slots F, the edges X are in practice further depressed, as shown in FIG. 19, thus forming broader inlets Y in slots F and also forming outwardly projecting peripheral wall portions M similar to domes between adjacent slots F.
PROBLEMS IN THE PRIOR ART
When using the stamping operation shown in FIGS. 15-17, the width W of the escapement hole H is only slightly greater than the width Z of the punch. Therefore, the peripheral wall of the header pipe A is sheared immediately after the start of the press operation, and the throat edge X of the tube insertion hole F is substantially perpendicular to the pipe periphery, as shown in FIG. 17. In this case, tube B can be inserted through tube insertion hole F only with difficulty. In addition, if tube B is inserted obliquely, it will be most difficult to withdraw it, and thus, reinsertion of the tube becomes cumbersome.
Further, as shown in FIG. 14, the area of the solder zone K between tube B and pipe A is reduced. That is, the mechanical strength of soldering is reduced, giving rise to the possibility of leakage of coolant.
In order to solve this problem, it may be thought to broaden the edge of tube insertion hole F by chamfering edge X after formation of the hole F. Doing so, however, increases the steps of the manufacturing operation--that is, it requires added time and labor, leading to an increase in cost.
When the dome-like peripheral wall portions M are formed between tube slots F of pipes A and C as shown in FIG. 19, there is the following problem:
Although the longitudinal edge portions X of tube insertion hole F are depressed as shown in FIGS. 18 and 19, the end portions M of the edges of the slots F (FIG. 18) are not depressed but remain substantially perpendicular to the pipe periphery. Therefore, when inserting tube B through tube insertion hole F, while a central portion of tube B in the width direction thereof is guided by depressed edge X and can be readily inserted, the end portions to tube B in the width direction can only be inserted with very great difficulty, particularly if they become slightly oblique or deviated with respect to tube insertion hole F. Besides, if tube B is obliquely inserted with irrational force, reinsertion become cumbersome, thus making the assembling very cumbersome.
OBJECT OF THE INVENTION
An object of the invention is to provide a header pipe for a coolant condenser, which permits ready insertion of the tubes through its receiving slots; provides for increased soldering area for securing the tubes; increases mechanical strength; and is inexpensive in price.
SUMMARY OF THE INVENTION
According to the present invention, there is provided a header pipe for a coolant condenser used for automobile air conditioners as shown in FIG. 1, in which the pipe 1 has radially elongated tube insertion slots 2, into which tubes B are received. The tube insertion hole 2 has an edge 3 which is broader than the outer diameter of tube B, and the edge 3 is formed with outwardly flaring curved guide surface 4.
Further, according to the present invention, as shown in FIGS. 6-10, each radially elongated tube insertion hole 3 has outwardly flaring guide portions 22 formed at opposite lateral ends 7 in the longitudinal direction of the hole.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view showing an embodiment of the pipe for a coolant condenser according to the invention;
FIG. 2 is a sectional view showin a manner of inserting a tube in a pipe shown in FIG. 1;
FIGS. 3 to 5 are views for explaining a process of forming a tube insertion hole in the pipe;
FIG. 6 is a perspective view showing a different embodiment of the pipe for a coolant condenser according to the invention;
FIG. 7 is a sectional view taken along line A--A in FIG. 6;
FIG. 8 is a fragmentary side view taken in the direction of arrow Z in FIG. 7;
FIGS. 9 and 10 are fragmentary sectional views showing different embodiments of the pipe for a coolant condenser according to the invention;
FIG. 11 is a view showing a coolant condenser;
FIG. 12 is a view for explaining flow of coolant in the coolant condenser;
FIG. 13 is a perspective view showing a prior art pipe for a coolant condenser;
FIG. 14 is a sectional view showing a manner of inserting a tube in the pipe shown in FIG. 13;
FIGS. 15-17 are views illustrating a process of forming a tube insertion hole in a pipe in the prior art;
FIG. 18 is a perspective view showing a different prior art pipe for a coolant condenser; and
FIG. 19 is a sectional view showing the pipe of FIG. 18 together with inserted tubes and mounted fins.
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the Invention
As seen in FIGS. 1 and 2, the header pipe according to the invention is referred to generally by the numeral 1 and is provided with radially oblong slots 2 for receiving the ends of tubes B. The tube receiving slots 2 each have edges 3 which are broader than the width dimensions of tube B. The edges 3 are bevelled to provide outwardly flaring curved guide surfaces 4 as shown in FIG. 2.
As shown in FIG. 3, the bevelled surfaces 4 are formed, employing a punch 11 in combination with an escapement hole 12 in core 13. The punch 11 has a width T which is equal to or slightly less than the width of the receiving hole 2 which is to be formed, while the escapement hole 12 has a width U which is greater than the width of the receiving hole 2. As a specific example, with the width of tube insertion hole 2 set to 2.1 mm, punch 11 has width T of 2.0 mm, and the width U of escapement hole 12 is 2.5 mm.
The stamping operation is performed after aligning the punch 11 and escapement hole 12. In this operation, the peripheral wall 15 of the header pipe 1 is not immediately sheared because the escapement hole 12 is greater in dimensions than punch 11. More specifically, as shown in FIG. 3, for a while after the commencement of the stamping operation, the peripheral wall 15 is pushed without shearing by punch 11 into escapement hole 12, where it is eventually curved inwardly as shown in FIG. 4. With the operation continued from this state, the peripheral wall 15 is eventually stamped out, and thus tube insertion hole 2 is formed. At this time, curved guide surface 4 (i.e. chamfered edge) is formed as part of peripheral wall 15 at the edge 3 of the hole 2.
It will be seen that tube receiving hole 2 and curved guide surface 4 are formed in a single stamping operation. in this case, if the difference between the width T of the punch 11 and the width U of escapement hole 12 is excessive, burrs are liable to be formed on the inner edge of the hole 2. For this reason, the width T of punch 11 and width U of escapement hole 12 are closely selected such that no burrs will be formed.
FIGS. 6-10 show other embodiments of the invention.
Referring to these figures, the header pipe 1 has its peripheral wall stamped with radially elongate tube receiving slots 2 for inserting tubes B therethrough. The edge 3 of each hole 2 is formed with longitudinally extending portions 3a are depressed during the stamping operation into a shape facilitating the insertion of tube B.
The opposite ends 7 of the receiving hole 2 are formed with bevelled insertion guides 22, as shown in FIGS. 7 to 10. These guides 22 serve to permit ready insertion of tube B into the hole 2 even if tube B is inclined with respect to the width direction of the hole or deviated sidewise when inserting the tube.
The bevelled insertion guides 22 shown in FIGS. 7 and 8 are linearly chamfered such that they flare outwardly.
The bevelled insertion guides 22 shown in FIG. 9 are chamfered in a curved fashion such that they flare outwardly.
The bevelled insertion guides 22 shown in FIG. 10 flare linearly outwardly and have outer guide projections 23. To form these tube insertion guides 23, the receiving hole 2 is formed by stamping in the direction of arrow in FIG. 10 using stamping punch 25 with projections 26 having the same shape as guides 22. By so doing, a single press operation simultaneously forms tube insertion hole 2 and the guide projections 23, all as a result of outward shift of excess material from the outer periphery of pipe 1 as shown in FIG. 10. With the formation of guide projections 23 a gap 24 is formed between tube B and pipe 1 when tube B is inserted into hole 2 is increased. Thus, the soldering area of pipe 1 and tube B is increased to improve the mechanical strength of soldering.
While the insertion guides 22 shown in FIGS. 7-10 are formed at the opposite ends of hole 2 in the longitudinal direction, it is possible to form a guide only at one end of the tube insertion hole.
Status of Use of the Invention
As will be appreciated, the slots 2 are formed with straight, radially directed walls which are curved, chamfered, or otherwise tapered only on the exterior surface of the pipe, forming the inlet to the slot. The long edge 3 of receiving hole 2 is broader than the outer dimensions of tube B inserted through tube insertion hole 2, and edge 3 is formed with outwardly flaring curved guides 4 as shown in FIG. 2. Thus, even if tube B is slightly deviated in position or bent when it is inserted through hole 2, it can be guided by curved guides 4 to correct the deviation or it may be bent and eventually inserted perpendicularly.
Further, since gap 6 is formed between each curved guide 4 of the hole 2 and tube B is inserted through hole 2, the area of soldering of tube B to pipe 1 is increased, and solder fills the gap 6, 26. Thus, the mechanical strength of soldering is increased.
Further, each header pipe shown in FIGS. 6-10 has radially elongate tube insertion slots 2 which are formed with outwardly flaring tube insertion guides 22 at opposite ends 7 in its longitudinal direction. Thus, even if tube B is slightly deviated in position or bent when it is inserted through the hole 2, its position can be corrected as it is guided by the guides 22 until it is eventually perpendicularly inserted.
Advantages of the Invention
The pipe for a coolant condenser according to the invention has the following advantages:
1) Curved guides 4 formed along the edge 3 of each tube insertion hole 2 or tube insertion guides 22 formed at opposite ends 7 of the hole 2 in the longitudinal direction thereof have the effect of correcting possible deviations or any bend of tube B, at the time of insertion. Thus, the insertion of tube B is greatly facilitated.
2) Since gap 6 is formed between tube B inserted through tube insertion hole 2 and each curved guide 4 or gap 24 is formed between tube B inserted through tube insertion hole 2 and each tube insertion guide 22, the soldering area is increased, resulting in greater mechanical strength and reducing the danger of leakage.
3) By forming guide projections 23 such that they project outwardly from the peripheral wall of pipe 1, gap 24 is increased to further increase the soldering area, further increasing the mechanical strength of soldering.
4) By arranging curved guides 4 or tube guides 22 simultaneously with hole 2 by a press operation, it is possible to reduce expenditures for processing and ultimately provide an inexpensive header pipe.
5) By forming the hole 2 such that the longitudinal portions 3a of edge 3 are depressed, even if tube B is slightly deviated not only in the lateral direction but also in the vertical direction of tube B, such deviation or bend can be easily corrected, and tube B may be thus eventually inserted perpendicularly. It is thus possible to automate the assembling.
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A header pipe is formed with a plurality of oblong slots which extend radially through the wall of the pipe and have an outside dimension larger than that of the tubular heat exchanger which is inserted in the slot. The peripherally directed edges on the exterior surface of the pipe surrounding the slots are curved to flare outwardly to form a taper for the insertion of the tubular heat exchanger.
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CLAIM OF PRIORITY
[0001] This application is a divisional application based on U.S. patent application Ser. No. 11/240,974 filed on Sep. 30, 2005 which is a continuation-in-part of U.S. patent application Ser. No. 10/261,839, filed on Sep. 30, 2002, and entitled “M ETHOD AND A PPARATUS FOR D RYING S EMICONDUCTOR W AFER S URFACES U SING A P LURALITY OF I NLETS AND O UTLETS H ELD IN C LOSE P ROXIMITY TO THE W AFER S URFACES ,” from which priority under 35 U.S.C. §120 is claimed. The disclosure of each of the above noted applications is incorporated herein by reference in their entirety.
BACKGROUND
[0002] The present invention relates generally to substrate preparation and/or cleaning and, more particularly, to systems, apparatus, and methods for improving preparation and/or cleaning of semiconductor substrate front surfaces.
Description of the Related Art
[0003] The fabrication of semiconductor devices involves numerous processing operations. These operations include, for example, dopant implants, gate oxide generation, inter-metal oxide depositions, metallization depositions, photolithography patterning, etching operations, chemical mechanical polishing (CMP), etc. Patterning and etching operations can be used to define features of a semiconductor device in the semiconductor wafer. In the patterning operation, a layer of photoresist material is deposited onto an intermediate layer formed over the semiconductor wafer. Thereafter, the photoresist layer is patterned by photolithography. At this point, the semiconductor wafer is exposed to light filtered by a reticle patterned with the desired integrated circuit layer features. As a result of being exposed, the light impinges upon the surface of the photoresist material, changes the chemical composition of the photoresist material, and creates a number of polymerized photoresist sections. The polymerized photoresist sections are then removed using a solvent, leaving a number of photoresist lines. At this point, the semiconductor wafer is etched. The portions of the underlying layer not protected by the photoresist material are removed, thus forming the desired semiconductor device features in the semiconductor wafer. Prior to proceeding to the next operation, however, the photoresist lines may need to be removed, and semiconductor wafer surfaces may need to be cleaned.
[0004] Chemicals can be used in a wet processing operation to remove the photoresist lines. In one approach, the photoresist lines are exposed to chemicals capable of reducing the adhesion at the interface of the photoresist lines and the underlying layer. Removing the photoresist lines using the latter approach requires that batches of semiconductor wafers be placed in tanks filled with such chemicals. Reducing the adhesion at the interface of the photoresist lines and the underlying layer, however, requires the soaking of the semiconductor wafers in the chemicals for an extended period and until the photoresist material is completely soaked. The soaking of batches of semiconductor wafers in tanks filled with chemicals is disfavored, as chemicals can be costly, and the wet operation can be very time consuming.
[0005] One way to expedite the removal of the photoresist material is to couple megasonic with the operation of chemical photoresist stripping. Achieving the latter, however, can be very costly as the megasonic equipment and the chemicals implemented for photoresist stripping have to be chemically compatible. Furthermore, applying megasonic to the semiconductor wafer frontside (i.e., the active side or top surface) can undesirably damage the semiconductor devices, thus resulting in defective semiconductor wafers.
[0006] After removing of the photoresist lines, but before performing the next process, the semiconductor wafers should be cleaned so that the generated residues and particulate contaminants adhered to the semiconductor wafer surfaces can be removed. Such particulate contaminants can consist of tiny bits of distinctly defined material having an affinity to adhere to the surfaces of the substrate. Examples of particulate contaminants can include organic and inorganic residues, such as silicon dust, silica, slurry residue, polymeric residue, metal flakes, atmospheric dust, plastic particles, and silicate particles, among others. Failure to remove the particulate contaminants from the semiconductor wafer frontside can have detrimental effects on the performance of the semiconductor devices formed thereon, ultimately resulting in defective semiconductor wafers.
[0007] In the same manner, failure to adequately and properly clean and process semiconductor wafer backside (i.e., non-active side) can be detrimental. For instance, unfortunately, residues and contaminant particulates on semiconductor wafer backsides can migrate from the semiconductor wafer backside to the semiconductor wafer frontside. For example, the migration may occur during a wet processing step and/or as the substrate is being moved or otherwise handled between the processing or metrology tools. Additionally, any residual fluid on the semiconductor wafer backside can migrate to the substrate frontside, thus re-contaminating the otherwise cleaned semiconductor wafer frontside. Furthermore, the residual fluid maybe introduced to the otherwise cleaned and dried substrates in the output cassette. Furthermore, the backside contaminants can undesirably migrate from the tools or steps of one process to tools and steps of the following processes, thus contaminating the subsequent processes. Consequently, the migration of residual fluid can compromise the quality of the substrate preparation operations, and as such, is disfavored.
[0008] In view of the foregoing, there is a need for a system, apparatus, and method capable of improving the semiconductor wafer preparation and cleaning operations without substantially damaging the semiconductor devices formed on the semiconductor wafer frontsides.
SUMMARY
[0009] Broadly speaking, the present invention fills these needs by providing a method, apparatus, and system for improving a semiconductor substrate preparation and/or cleaning operations without substantially damaging semiconductor devices formed on the substrate frontsides. In one example, the present invention improves substrate preparation and/or cleaning operations by enhancing a mass transport of a preparation chemical to a reaction interface defined between the material to be removed and the substrate frontside. According to one aspect, the mass transport of the preparation chemistry to the reaction interface is achieved by applying megasonic energy to a backside of the substrate and the transmission of the megasonic energy to the reaction interface through a megasonic coupling fluid meniscus and the substrate. In accordance with one aspect, the megasonic coupling fluid meniscus having a lower temperature can be implemented to isolate a higher temperature condition on the substrate frontside (i.e., the process side) from a megasonic coupling proximity head defined on the substrate backside.
[0010] It should be appreciated that the present invention can be implemented in numerous ways, including as a process, an apparatus, a system, a device, or a method. Several inventive embodiments of the present invention are described below.
[0011] In one embodiment, method for cleaning a substrate is provided. The method includes receiving the substrate using a carrier that forms a circular opening, the substrate being positioned in the circular opening of the carrier. The holding of the substrate enables exposure of both a first side and a second side of the substrate at a same time. Then, moving the substrate along a direction, and while moving the substrate: (i) applying a chemistry onto the first side of the substrate, where the first side of the substrate having material to be removed; (ii) forming a fluid meniscus against the second side of the substrate at a location that is opposite a location onto which the chemistry is applied; and (iii) applying megasonic energy to the fluid meniscus while the fluid meniscus is applied against the second side. The megasonic energy increases mass transport of the chemistry to enhance removal of the material to be removed from the first side.
[0012] According to another embodiment of the present invention, a method for enhancing the mass transport of a chemistry in a material to be removed is provided. The method includes applying the chemistry on the material to be removed and forming a back meniscus on a second side of the substrate. The material to be removed is defined on a first side of a substrate. Megasonic energy is applied to the back meniscus. The megasonic energy is transmitted to an interface defined between the material to be removed and the first side of the substrate through the back meniscus such that the mass transport of the chemistry through the material to be removed is enhanced.
[0013] According to yet another embodiment of the present invention, a substrate preparation system is provided. The system includes a proximity head and a megasonic proximity head. The megasonic proximity head includes a resonator and a crystal. The resonator has a first side and a second side and the first side of the resonator faces the substrate backside. The crystal is defined on the second side of the resonator. The vibration of the crystal is configured to generate megasonic energy. The proximity head is configured to be applied to a substrate frontside and is capable of generating a preparation meniscus on the substrate frontside. The preparation meniscus includes a preparation chemistry that is configured to remove a material to be removed defined on the substrate frontside. The megasonic proximity head is configured to be applied to a substrate backside and is capable of generating megasonic energy. The megasonic energy is configured to enhance a mass transport of the preparation chemistry through the material to be removed.
[0014] In accordance with still another embodiment of the present invention, an apparatus for isolating a temperature of a process side of a substrate is provided. The apparatus includes a megasonic proximity head that is configured to be applied to a non-process side of the substrate. The megasonic proximity head is capable of generating a coupling meniscus on the non-process side of the substrate. Lowering a temperature of the coupling meniscus is configured to decouple the temperature of the process side of the substrate from the non-process side of the substrate.
[0015] The advantages of the present invention are numerous. Most notably, the present invention can substantially reduce undesirable damage to the semiconductor devices formed over the substrate frontside by transmission of the megasonic energy to the interface through the substrate backside and the substrate. Furthermore, megasonic energy is not being applied directly to the semiconductor devices defined on the substrate frontside, thus substantially reducing the possibility of dislodging or damaging the semiconductor features formed therein. Yet further, enhancing the mass transport of the preparation chemistry through the material to be removed requires a lower level of megasonic energy.
[0016] Other aspects and advantages of the invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings, illustrating by way of example the principles of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] The present invention will be readily understood by the following detailed description in conjunction with the accompanying drawings, and like reference numerals designate like structural elements.
[0018] FIG. 1A is a simplified, partial, side view of an exemplary proximity preparation system implementing an exemplary megasonic coupling proximity head, in accordance with one embodiment of the present invention.
[0019] FIG. 1B is a simplified, partial, magnified, cross sectional view of the proximity preparation system depicted in FIG. 1A , in accordance with one embodiment of the present invention.
[0020] FIG. 1C is a simplified magnification of a region A shown in FIG. 1B , in accordance with yet another embodiment of the present invention.
[0021] FIG. 1D is a simplified top view of an exemplary megasonic coupling proximity head, in accordance with still another embodiment of the present invention.
[0022] FIG. 2 depicts an exemplary semiconductor wafer preparation system implementing an exemplary megasonic coupling proximity head in conjunction with a two-bar-type proximity head apparatus, in accordance with still another embodiment of the present invention.
[0023] FIG. 3A is a simplified cross sectional view of an exemplary megasonic coupling proximity head, in accordance with another embodiment of the present invention.
[0024] FIG. 3B is a top view of an exemplary megasonic coupling proximity head shown in FIG. 3A , in accordance with another embodiment of the present invention.
[0025] FIG. 3C is a bottom view of an exemplary megasonic coupling proximity head shown in FIG. 3A , in accordance with another embodiment of the present invention.
[0026] FIGS. 4A shows a top view of a portion of a proximity head in accordance with one embodiment of the present invention.
[0027] FIG. 4B illustrates an inlets/outlets pattern of a proximity head in accordance with another embodiment of the present invention.
[0028] FIG. 4C illustrates another inlets/outlets pattern of a proximity head in accordance with still another embodiment of the present invention.
[0029] FIG. 4D illustrates a further inlets/outlets pattern of a proximity head in accordance with yet another embodiment of the present invention.
[0030] FIG. 4E illustrates a further inlets/outlets pattern of a proximity head in accordance with yet another embodiment of the present invention.
DETAILED DESCRIPTION
[0031] An invention capable of improving substrate preparation and/or cleaning operations without substantially damaging semiconductor devices formed on substrate frontsides is provided. In one example, the present invention improves substrate preparation and/or cleaning operations by enhancing a mass transport of preparation chemistry to a reaction interface on the substrate frontside. According to one aspect, the enhancing of the mass transport of the preparation chemistry to the reaction interface is achieved by imparting megasonic energy to the interface through a megasonic coupling fluid meniscus coupled to a backside of the substrate. In one example, the megasonic energy imparted to the reaction interface further assists in breaking a bond or a force between the material to be removed and/or the residues or particulate contaminants, and the substrate frontside at the reaction interface, thus resulting in the removed of the residues, particulate contaminants, and/or the material to be removed.
[0032] In one aspect, the megasonic energy imparted by a megasonic coupling proximity head is implemented to enhance the mass transport of the preparation chemistry implemented to prepare the substrate frontside. In one example, the megasonic energy facilitates the moving of the molecules of the preparation chemistry to the interface (herein also referred to as the reaction site) (e.g., the interface between the photoresist layer and the substrate frontside, or the interface between the residue and/or the particulate contaminants and the substrate frontside) and removing of the reaction by-products generated as a result of the chemical reaction between the preparation chemistry and the material being removed from the reaction site. In one instance, implementing the megasonic coupling proximity head of the present invention enhances the mass transport of the chemicals to the reaction side and moving of the reaction by-products from the interface.
[0033] According to one embodiment, the megasonic coupling proximity head of present invention faces the substrate backside and substantially opposite a proximity head configured to prepare the semiconductor wafer frontside using a meniscus. The megasonic energy imparted by the megasonic coupling proximity head of the present invention is transmitted to the megasonic coupling fluid meniscus generated by the megasonic coupling proximity head. Thereafter, the megasonic energy is imparted to the substrate backside and the interface. According to one embodiment, meniscus is disclosed in U.S. patent application Ser. No. 10/261,839, filed on Sep. 30, 2002, and entitled “M ETHOD AND A PPARATUS FOR D RYING S EMICONDUCTOR W AFER S URFACES USING A P LURALITY OF I NLETS AND O UTLETS H ELD IN C LOSE P ROXIMITY TO THE W AFER S URFACES ,” AND is incorporated herein by reference in its entirety.
[0034] In one embodiment of the present invention, a cooling fluid (e.g., nitrogen) can be introduced to an inner area of the transducer and the backside of the crystal so as to lower the temperature of the transducer. In another example, a higher temperature of the meniscus being applied to the substrate frontside can be isolated from the transducer using the megasonic coupling fluid meniscus having a lower temperature. In one example, a cooled megasonic fluid can be introduced into the megasonic coupling proximity head. In this manner, the megasonic coupling fluid meniscus having a lower temperature can be implemented to isolate the temperature condition on the substrate frontside (i.e., the process side) from the transducer defined on the substrate backside.
[0035] FIG. 1A is a simplified, partial, side view of an exemplary proximity preparation system 100 implementing an exemplary megasonic coupling proximity head 111 , in accordance with one embodiment of the present invention. The system 100 includes a proximity head 110 , the megasonic coupling proximity head 111 , and an RF power supply component 128 . In the illustrated embodiment, the proximity head 110 and the megasonic coupling proximity head 111 are bar-shaped and are defined on opposite sides of a semiconductor wafer 102 . The proximity head 110 faces a semiconductor wafer frontside 102 a while the megasonic coupling proximity head 111 faces a semiconductor wafer backside 102 b. While the proximity head 110 and the megasonic coupling proximity head 111 extend the entire diameter of the semiconductor wafer 102 , the proximity head 110 and the megasonic coupling proximity head 111 partially cover the semiconductor wafer frontside and backside 102 a and 102 b, respectively. The proximity head 110 is configured to prepare the semiconductor wafer frontside 102 a using a meniscus 116 . As used herein, meniscus 116 is the portion of fluids (e.g., preparation chemistry, pre-rinse fluid, IPA vapor, DI water, etc.) defined in a region between the proximity head 110 and the semiconductor wafer frontside 102 a.
[0036] In one example, the megasonic coupling proximity head 111 is configured to assist the proximity head 110 in preparing the semiconductor frontside 102 a. According to one aspect, the semiconductor wafer 102 is configured to be moved in a direction 120 while the megasonic coupling proximity head 111 and the proximity head 110 remain stationary. In the illustrated embodiment, the proximity head 110 is configured to strip a photoresist layer 104 from over the semiconductor wafer 102 . In another example, the proximity head 110 can be configured to remove any desired layer of material and/or residues and particulate contaminants from over the semiconductor wafer frontside 102 a.
[0037] As can be seen, a portion 104 ′ of the photoresist layer 104 has already been removed from over the semiconductor wafer frontside 102 a, as depicted by the dotted lines. The portion 104 ′ corresponds to a processed section D of the semiconductor wafer frontside 102 a. As described in more detail below, the processing of the section D by the proximity head 110 has been assisted by the megasonic coupling proximity head 111 being applied to the semiconductor wafer backside 102 b.
[0038] In one example, the meniscus 116 includes a preparation chemistry configured to strip the photoresist layer 104 from over the semiconductor wafer frontside 102 a. According to one embodiment, the megasonic energy imparted by the megasonic coupling proximity head 111 onto the semiconductor backside 102 b is configured to enhance the mass transport of the preparation chemistry through the photoresist layer 104 and to an interface 103 (i.e., the interaction site) defined between the photoresist layer 104 and the semiconductor wafer frontside 102 a. Mass transport refers to the diffusion of chemicals being used to remove the residues, particulate contaminants, and/or a layer of material through the material to be removed and down to an interface defined between the material to be removed and an underlying layer. The mass transport of the preparation chemistry further includes the removing of the by-products generated as a result of the chemical reaction between the materials to be removed and/or the particulate contaminants from the interface. However, as is described in more detail below, the chemical reaction between the preparation chemistry and the photoresist layer 104 can be a mass transport limited reaction. That is, the preparation chemistry can diffuse through the photoresist layer 104 (i.e., the material to be removed) and can react with the photoresist material (i.e., the material to be removed), generating by-products. The generated by-products, however, cover the photoresist layer (i.e., the material to be removed). As such, unless the generated by-products covering the photoresist layer are removed from the interface, the covered portions of the material to be removed cannot enter into chemical reaction with the preparation chemistry. Consequently, undesirably, the rate of chemical reaction is reduced. Accordingly, the megasonic coupling proximity head of the present invention is implemented to enhance the mass transport in a mass transport limited reaction.
[0039] The illustrated megasonic coupling proximity head 111 includes a housing 106 and a transducer 113 . A top surface 106 a of the housing 106 includes a weir 114 and faces the semiconductor wafer backside 102 b. A megasonic fluid (not shown in FIG. 1A ) is introduced into the housing 106 and ultimately into a well 120 , thus forming the megasonic coupling fluid meniscus 112 . In one example, as the megasonic coupling fluid meniscus 112 is formed and as the semiconductor wafer backside 102 b gets closer to the megasonic coupling fluid meniscus 112 , the megasonic coupling fluid 112 acts as a seal, coupling the semiconductor wafer backside 102 b to the megasonic coupling proximity head 111 . Additional information with respect to the megasonic coupling fluid 112 is provided below with respect to FIGS. 1B-4 .
[0040] The transducer 113 includes a resonator 109 and a crystal 108 defined on an inner surface of the resonator 109 . In one exemplary embodiment, the vibrations of the crystal 108 and thus the transducer 113 create sonic energy in the megasonic coupling fluid meniscus 112 . The sonic agitation generated by the transducer 113 is thus imparted to the semiconductor wafer backside 102 b through the megasonic coupling fluid meniscus 112 , and ultimately to the interface 103 . The coupled megasonic coupling fluid meniscus enhances the mass transport of the preparation chemistry through the photoresist layer 104 to the interface as well as assisting in the breaking of the bond between the photoresist layer and the semiconductor wafer frontside 102 a at the interface 103 .
[0041] FIG. 1B is a simplified, partial, magnified cross sectional view of the proximity preparation system 100 depicted in FIG. 1A , in accordance with another embodiment of the present invention. According to one example, the housing 106 is constructed from a chemically inert material (e.g., PET, plastics, polyurethane, etc.). The exemplary housing 106 of the megasonic coupling proximity head 111 includes channels 124 , which extend from a bottom surface 106 b of the housing 106 to a top surface 106 a of the housing 106 .
[0042] The megasonic fluid is introduced into the housing 106 through inlets 122 of the channels 124 , and ultimately into the well 120 formed between an outer surface of the resonator 109 , sidewalls 106 d of the housing 106 , and the top surface 106 a of the housing 106 , thus forming the megasonic coupling fluid meniscus 112 . As can be seen, the megasonic fluid meniscus 112 is further confined by the semiconductor wafer backside 102 b. As such, the megasonic coupling fluid meniscus 112 seals the megasonic coupling proximity head 112 to the semiconductor wafer backside 102 b. One of ordinary skill in the art must appreciate that although in the illustrated embodiment the resonator 109 extends between the inner sidewalls 106 d of the housing 106 , in another embodiment, the resonator 109 can also extend along the inner sidewalls 106 d of the megasonic coupling proximity head 111 so that megasonic energy can be imparted to the megasonic fluid while the megasonic fluid is in the channels 124 and before being diverted into the well 120 . Furthermore, although in the illustrated embodiment the megasonic coupling proximity head 111 includes a weir 114 , in another embodiment, a weir may not be included so long as the tolerance required to control suction of the megasonic coupling fluid meniscus can be achieved.
[0043] However, as shown by arrows 119 , the megasonic coupling fluid meniscus 112 can over flow over the top surface 106 a of the housing 106 and into a weir 114 . Thereafter, the overflowed megasonic coupling fluid meniscus 112 can be expelled from the housing 106 and the weir 114 through outlets 126 of channels 127 extending from the weir 114 to the bottom surface 106 b of the housing 106 . In one example, the megasonic fluid is deionized water. Of course, in another embodiment, the megasonic fluid can be any suitable fluid so long as the function of imparting the megasonic energy to the interface 103 can be achieved (chemistry, etc.).
[0044] The crystal 108 secured to the inner surface of the resonator 109 is in communication with the RF power supply component 128 that is configured to provide the crystal 108 electrical energy along the direction of arrows 130 . In one example, the crystal 108 is bonded to the inner surface of the resonator 109 . However, in another embodiment, the crystal 108 can be secured to the inner surface of the resonator 109 using any appropriate technique.
[0045] According to one example, as electrical energy is applied to the crystal 108 , the crystal 108 starts imparting energy to the megasonic coupling fluid meniscus 112 . The energy imparted to the megasonic coupling fluid meniscus 112 is in turn passed through the semiconductor wafer backside 102 b and the semiconductor wafer 102 to the interface 103 . At times, the megasonic energy can also be imparted to the semiconductor wafer frontside 102 a and the meniscus 116 . In this manner, the mass transport of the preparation chemistry is enhanced even though the megasonic energy is not being directly imparted to the photoresist layer 104 .
[0046] The megasonic coupling fluid meniscus 112 defined between the megasonic coupling proximity head 111 and the semiconductor wafer backside 102 b, and is applied onto the semiconductor wafer backside in a stable and controllable manner. In one embodiment, the megasonic coupling fluid meniscus 112 may be confined by a constant application and removal of the megasonic fluid. According to one example, surface tension gradient technology (STG) such as IPA vapor can be implemented to define the megasonic coupling fluid meniscus 112 . For instance, IPA can be applied so as to maintain an encapsulated area of megasonic fluid above or below a surface, or between surfaces. The vacuum removes the IPA and the megasonic fluid along with any residues and/or particulate contaminants that may reside on the semiconductor wafer backside 102 b.
[0047] It must be noted that although in the illustrated embodiment a single crystal 108 is shown to be bonded to the inner surface of the resonator 109 , in another embodiment, any appropriate number of crystals 108 can be implemented so long as the function of generating megasonic energy can be achieved. According to one aspect, the transducer 113 of the present invention can include an array of staggered crystals. Additional information with respect to implementing array of staggered crystals is provided in U.S. patent application Ser. No. 10/371,679, filed on Feb. 20, 2003, having inventors Tom, Anderson and John M. Boyd, and entitled “D ISTRIBUTION OF E NERGY IN A H IGH F REQUENCY R ESONATING W AFER P ROCESSING S YSTEM .” The disclosure of this Application, which is assigned to Lam Research Corporation, the assignee of the subject application, is incorporated herein by reference.
[0048] In one embodiment, the crystal 108 may provide a movement frequency between about 20 KHz and 500 KHz. In another implementation, the megasonic frequency can range between approximately about 0.5 MHz and about 2 MHz. In one example, the crystal 108 is a piezoelectric crystal. It must be appreciated by one of ordinary skill in the art that the piezoelectric crystals can be made of any appropriate piezoelectric material (e.g., piezoelectric ceramic, lead zirconium tintanate, piezoelectric quartz, gallium phosphate, etc.). In a like manner, the resonator 109 can be made of any appropriate material (e.g., ceramic, silicon carbide, stainless steel, aluminum, quartz, etc.). Additionally, one having ordinary skill in the art must appreciate that a thickness of the piezoelectric crystal 108 depends on the design of the crystal 108 , mechanical strength of the crystal material, and type of crystal material. In one example, the thickness of the piezoelectric crystals is configured to range between approximately about 1 mm and about 6 millimeter, and a more preferred range of approximately about 2 mm and 4 mm and most preferably between approximately about 1 mm to approximately about 2 millimeters. In another embodiment, wherein the crystals are ceramic type crystals, the thickness of the crystals is configured to range between approximately about 1 mm to about 4 mm.
[0049] Preparation of the semiconductor wafer frontside 102 causing the proximity head 110 and the application of the megasonic energy to the semiconductor backside 102 b can be advantages for several reasons. For instance, megasonic energy is not being applied directly to the semiconductor devices defined on the semiconductor wafer frontside, thus substantially reducing the possibility of dislodging or damaging the semiconductor features formed therein. Furthermore, enhancing the mass transport of the preparation chemistry through the material to be removed requires a lower level of megasonic energy. Thus, in one aspect, megasonic energy having a level lower than that of the damage threshold can be imparted to the backside of the semiconductor wafer so as to enhance chemical reaction at the reaction site defined on the semiconductor wafer frontside 102 a. In one example, the level of megasonic energy being applied onto the semiconductor backside 102 b can range between about 0.1 watt per square centimeter (W/cm 2 ) to about 10 W/cm 2 , and more specifically, between about 0.1 W/cm 2 and about 1 W/cm 2 .
[0050] Of course, the level of megasonic energy being implemented can be higher if the megasonic coupling proximity head is being implemented to facilitate mass transport of the preparation chemistry on a substrate frontside having patterns that are not sensitive to the megasonic energy, or a substrate frontside that is not patterned. Accordingly, the megasonic coupling proximity head of the present invention can be implemented to clean the frontside of the semiconductor wafers depending on the topography on the semiconductor wafer or the process being implemented.
[0051] FIG. 1C is the simplified, partial, magnified, cross sectional view of a region A shown in FIG. 1B , illustrating the mass transport of the preparation chemistry through the photoresist layer 104 , in accordance with one embodiment of the present invention. As shown, a section 104 a of the photoresist layer 104 is being processed by the meniscus 116 while the section 104 b has not yet been exposed to the meniscus 116 . Portions 104 ′ of the section 104 a have been removed (as shown by the dotted lines and dotted arrows 134 ), whereas certain portions of the section 104 a have remained intact. Nonetheless, by the time the front meniscus 116 has passed over the section 104 a of the photoresist 104 , the photoresist material in the section 104 a have been removed.
[0052] As shown, the semiconductor wafer 102 attenuates portions of the megasonic energy imparted by the megasonic coupling proximity head 111 of the present invention. Specifically, the semiconductor wafer 102 has attenuated the megasonic energy illustrated by arrows 130 at the interface 103 , while the megasonic energy illustrated by arrows 130 ′ have passed through the interface 103 and have reached the photoresist layer 104 . This is beneficial because the level of megasonic energy imparted to the semiconductor wafer frontside 102 a is below the damage threshold, thus preventing damaging of the semiconductor devices.
[0053] FIG. 1D is a simplified top view of an exemplary megasonic coupling proximity head, in accordance with on embodiment of the present invention. In the illustrated embodiment, the top surface 106 a of the megasonic coupling proximity head 111 has a rectangular shape. Of course, in another embodiment, the top surface of the megasonic coupling proximity head 111 can have any appropriate shape so long as the function of enhancing the mass transport of the meniscus through the material to be removed can be achieved. A plurality of vacuum holes 114 ′ are defined in the weir 114 . In one example, the vacuum holes 114 are used to evacuate the megasonic coupling fluid meniscus 112 from the well 120 . In another embodiment, the megasonic coupling fluid meniscus 112 can be removed while using STG to confine the meniscus 112 to a specific region.
[0054] Reference is made to FIG. 2 depicting an exemplary semiconductor wafer preparation system 200 implementing yet another exemplary megasonic coupling proximity head in conjunction with a two-bar-type proximity head apparatus preparation, in accordance with one embodiment of the present invention. The system 200 includes a chamber 142 , a system controller 138 , and an actuating component 136 . According to one aspect, the system controller 138 controls the operations of a leading proximity head 110 a, the megasonic coupling proximity head 111 , a trailing proximity head 110 b, and a back proximity head 110 c.
[0055] In accordance with one aspect of the present invention, the megasonic coupling proximity head 111 is configured to assist the leading proximity head 110 a in stripping the photoresist layer 104 from over the semiconductor wafer frontside 102 a. Comparatively, the trailing proximity head 110 b and the back proximity head 110 c are configured to respectively rinse and dry the semiconductor wafer frontside 102 a subsequent to the removal of the photoresist layer 104 and the backside 102 b subsequent to the cleaning of the backside 102 b by the megasonic coupling proximity head 111 . Of course, in another embodiment, the leading proximity head 110 a can be implemented to dislodge and remove residues and particulate contaminant from over the semiconductor wafer frontside 102 a.
[0056] As can be seen, the leading and trailing proximity heads 110 a and 110 b are defined consecutively and, are secured to an inner sidewall of the chamber 142 by a corresponding railing 118 . In the same manner, the back proximity head 110 c and the megasonic coupling proximity head 111 are defined consecutively and are secured to the inner wall of the chamber by the railing 118 . The trailing proximity head 110 b and the back proximity head 110 c are defined opposite one another with the trailing proximity head 110 b being defined proximate to the semiconductor wafer frontside 102 a and the backside proximity head 110 c being defined proximate to the semiconductor wafer backside 102 b. In the same manner, the leading proximity head 110 a and the megasonic coupling proximity head 111 are defined opposite one another with the leading proximity head 110 a being proximate to the semiconductor wafer frontside 102 a and the megasonic coupling proximity head 111 being proximate to the semiconductor wafer backside 102 b. Preferably, the pair of trailing and backside proximity heads 110 b and 110 c, as well as the pair of leading proximity head 110 a and the megasonic coupling proximity head 111 are applied onto the frontside 102 a and backside 102 b of the semiconductor wafer 102 , substantially simultaneously.
[0057] One of ordinary in the art must recognize and appreciate that although in the illustrated embodiment one pair of proximity head and one pair of proximity head-megasonic coupling head have been implemented, in a different embodiment, any appropriate number of proximity heads can be implemented (e.g., one, two, three, etc.). Furthermore, although in the illustrated embodiment the leading and trailing proximity heads 110 a and 110 b are supported by the single railing 118 , and the back proximity head 110 c and the megasonic coupling proximity head 111 are supported by the single railing 118 , in another embodiment, each of the leading and trailing proximity heads 110 a and 110 b, the back proximity head 110 c, and the megasonic coupling proximity head 111 can be supported in any appropriate configuration (e.g., each connected to the sidewall by a respective railing, etc.).
[0058] In the illustrated embodiment, the railings 118 , and thus the respective proximity heads and megasonic coupling proximity head are configured to be fixed. However, in a different embodiment, the pair of trailing and back proximity heads 110 b and 110 c and the pair of leading proximity head 110 a and megasonic coupling proximity head 111 can be configured to move within the chamber 104 so long as the megasonic coupling proximity head 111 can assist in the mass transport of the preparation chemistry through the material being removed. Additionally, in the illustrated embodiment, the semiconductor wafer 102 does not rotate, as the entire frontside and backside 102 a and 102 b of the semiconductor wafer 102 are being traversed and processed by the leading and trailing proximity heads, back proximity head 110 , and the megasonic coupling proximity head 111 .
[0059] With continued reference to FIG. 2 , the carrier 144 is coupled to the actuating component 136 via an aim 115 . In one example, the carrier 144 is a rectangular flat surface made of a composite material (e.g., polycarbonate, coated carbon fiber, quartz, aluminum, stainless steel, etc.). A circular opening in the carrier 144 forms an inner rim configured to hold the semiconductor wafer 102 to be prepared. In one example, the semiconductor wafer 102 is supported by the plurality of support members 146 secured to the inner rim of the carrier 144 . In one preferred embodiment the support members are pins.
[0060] One of ordinary skill in the art must appreciate that although in the illustrated embodiment the carrier 144 has a flat rectangular surface, in another embodiment, the carrier 144 may have any shape suitable for holding and processing the semiconductor wafer 102 . Additional information with respect to the carrier 144 and the supporting members 146 is provided in U.S. application Ser. No. ______ (Attorney Docket Number LAM2P521), filed on even date herewith having inventors Katrina Mikhaylichenko, Kenneth Dodge, Mikhail Korolik, Michael Ravkin, John M. de Larios, and Fritz C. Redeker, and entitled “S UBSTRATE P ROXIMITY D RYING U SING I N -S ITU L OCAL H EATING OF S UBSTRATE AND S UBSTRATE C ARRIER P OINT OF C ONTACT, AND M ETHODS, A PPARATUS, AND S YSTEMS FOR I MPLEMENTING THE S AME .” The disclosure of this Application, which is assigned to Lam Research Corporation, the assignee of the subject application, is incorporated herein by reference.
[0061] In operation, the substrate frontside and backside 102 a and 102 b are prepared as the carrier 144 and thus the semiconductor wafer 102 are transported horizontally in the movement direction 120 within the chamber 142 . The semiconductor substrate 102 is transported through the pair of proximity leading proximity head 110 a and megasonic coupling proximity head 111 as well as the pair of trailing and back proximity heads 110 b and 110 c. The megasonic coupling fluid meniscus 112 of the megasonic coupling proximity head 111 assists the preparation of the frontside 102 a by the meniscus 116 a. Additionally, the frontside and backside 102 a and 102 b are prepared (e.g., rinsed and dried) by menisci 116 b and 116 c, respectively. In one example, the megasonic coupling fluid meniscus 112 is configured to prepare the backside 102 b by dislodging and removing the residues and particulate contaminants thereon.
[0062] The system controller 134 is implemented to manage and monitor the actuating component 136 and the RF power component during operation. In one example, the system controller 134 can be a computer system. According to one embodiment, the actuating component 114 provides the system controller 138 with feedbacks as to selected parameters. In one embodiment, the actuating component 136 can be a motor, however, in a different embodiment, the actuating component 136 can be any component capable of moving the carrier 144 within the chamber 142 . Furthermore, one of ordinary skill in the art must appreciate that different mechanics and engineering can be implemented to move the carrier 144 and thus the semiconductor wafer 102 during operation.
[0063] In one aspect of the present invention, an in-situ integrated unit such a sensor 140 can be coupled to the railing 118 , between the leading proximity head 110 and trailing proximity head 110 b so as to ensure the completion of the photoresist removal. In this manner, after the leading proximity head 110 a has prepared the semiconductor wafer frontside 102 a and removed the photoresist layer 104 , the sensor 140 can inspect each portion of the semiconductor wafer frontside 102 a. Of course, the sensor 140 provides the control system 134 with feed back as to whether the removal of the photoresist layer 104 or the residue and particulate contaminants have been achieved properly. According to another example, the sensor 140 can be an integrated unit within the trailing proximity head 110 b. In one aspect, the sensor 140 can use different techniques to ensure the sufficient removal of the photoresist layer 104 (e.g., broad band spectroscopy, interferometry, vision system, etc.).
[0064] According to one example, a sufficient amount of energy should be applied to the transducer 113 to generate the megasonic energy. As a result, a significant amount of heat can be generated at the transducer 113 . Undesirably, the heat can degrade the bond between the resonator 109 and the crystal 108 , thus preventing the transducer 113 from operating properly. Thus, in one embodiment of the present invention, a cooling fluid (e.g., nitrogen) can be introduced to an inner area of the transducer 113 and the backside of the crystal 108 through an inlet 141 . The cooling fluid can thereafter be expelled using an outlet 143 .
[0065] Proceeding to FIG. 3A , a simplified cross sectional view of yet another embodiment of the megasonic coupling proximity head of the present invention is illustrated, in accordance in one aspect of the present invention. According to one example, the preparation of the semiconductor wafer frontside 102 a can be enhanced by using the meniscus 116 having a higher temperature. However, the higher temperature of the meniscus 116 can degrade the bonding between the resonator and the crystal in the transducer. Accordingly, in one embodiment, the temperature of the megasonic coupling fluid meniscus 112 can be controlled so as to decouple the meniscus 116 having a higher temperature from the transducer 113 . In one example, a cooled fluid can be introduced into the megasonic coupling proximity head so as to decouple the higher temperature of the meniscus 116 from the transducer 113 . Cooled megasonic fluid can be introduced into the apparatus 111 through the inlets 124 and be diverted into the well 120 , forming the megasonic coupling fluid meniscus 112 . Of course, due to the cool temperature of the megasonic fluid being introduced, the resulting megasonic coupling fluid meniscus 112 also has a lower temperature. In this manner, the megasonic coupling fluid meniscus 112 can be implemented to isolate the temperature condition on the semiconductor wafer frontside (i.e., the process side) from the transducer 113 .
[0066] In the illustrated embodiment, the resonator 109 of the transducer 113 is defined at an angle with respect to the semiconductor wafer backside 102 b. In one example, the angle between the resonator 109 and the backside 102 b can be adjusted by adjusting an angle plate 148 . For instance, by adjusting the angle plate 148 , a distance between the resonator 109 and the backside 102 b can be changed. As shown in the illustrated embodiment, the angle of the resonator 109 is reduced as the semiconductor wafer 102 is inserted between the proximity head 110 a and the megasonic coupling proximity head 111 ′, as illustrated by the dotted line.
[0067] FIG. 3B is a top view of an exemplary megasonic coupling proximity head 111 ′ shown in FIG. 3A , in accordance with another embodiment of the present invention. In the illustrated embodiment, megasonic fluid is configured to be introduced into the apparatus 111 ′ through the inlets 124 so as to fill the well 120 and form the megasonic coupling fluid meniscus 112 . Overflowed megasonic coupling fluid meniscus is configured to be diverted to the weir 114 and be eliminated from the apparatus through the outlets 126 . In one example, the overflowed megasonic coupling fluid meniscus 112 is eliminated by vacuum. The bottom view of the megasonic fluid apparatus 111 ′ is shown in FIG. 3C , in accordance with one embodiment of the present invention. As can be seen, megasonic fluid is introduced through inlets 124 and overflowed megasonic coupling fluid meniscus is eliminated through the outlets 126 .
[0068] One of ordinary skill in the art must appreciate that although in the illustrated embodiments megasonic fluid is introduced through two inlets 124 , in another embodiment, any appropriate number of inlets can be implemented to introduce the megasonic fluid into the apparatus 111 ′. Furthermore, although in the illustrated embodiments three outlets 126 are shown, in another embodiment, any suitable number of outlets can be implemented to dispose of the megasonic fluid from the apparatus 111 ′.
[0069] According to one embodiment of the present invention, the megasonic coupling proximity head can be incorporated in a clustered substrate processing system. For instance, after a substrate frontside and/or backside has been pre-processed in an etching chamber, a chemical vapor deposition system, a chemical mechanical polishing (CMP) system, etc., the megasonic coupling proximity head of the present invention can assist in preparation of the substrate frontside and back side. Thereafter, the semiconductor wafer backside and/or frontside can be post-processed in an etching chamber, a chemical vapor deposition (CVD) system, physical vapor deposition (PVD) system, electrochemical deposition (ECD) system, an atomic layer deposition (ALD) system, a lithographic processing system (including coater and stepper) module, etc.
[0070] Yet further, in one exemplary implementation, the megasonic coupling proximity head of the present invention can be implemented in a clustered substrate cleaning apparatus that may be controlled in an automated way by a control station. For instance, the clustered preparation apparatus may include a sender station, a proximity head assisted by a megasonic coupling proximity head of the present invention, and a receiver station. Broadly stated, substrates initially placed in the sender station are delivered, one-at-a-time, so as to be prepared by the proximity head and the megasonic coupling proximity head of the present invention. After being prepared, substrates are then delivered to the receiver station for being stored temporarily. One of ordinary skill in the art must appreciate that in one embodiment, the clustered cleaning apparatus can be implemented to carry out a plurality of different substrate preparation operations (e.g., cleaning, etching, buffing, etc.).
[0071] In an exemplary proximity system of the present invention, preparing the substrate surfaces using a meniscus of an exemplary proximity head is described in the following figures. One of ordinary skill in the art must appreciate that any suitable type of system with any suitable type of proximity head that can generate a fluid meniscus can be used with the embodiments of the present invention described herein.
[0072] FIG. 4A illustrates an exemplary proximity head 110 ′ performing a substrate processing operation, in accordance with one embodiment of the present invention. The proximity head 110 ′, in one embodiment, stays in place while the carrier and thus the substrate pass through each pair of front and back menisci 130 in close proximity to the front and back menisci so as to conduct the substrate processing operation.
[0073] It should be appreciated that depending on the type of fluid applied to the semiconductor wafer 102 , the fluid meniscus 116 generated by the proximity head 110 ′ on the substrate surface 102 may be any suitable substrate processing operation such as, for example, pre-rinsing, cleaning, drying, etc. In one embodiment, the proximity head 110 ′ includes source inlets 132 and 156 and a source outlet 154 . In such an embodiment, isopropyl alcohol vapor in nitrogen gas IPA/N 2 157 may be applied to the substrate surface through a source inlet 152 , vacuum 158 may be applied to the substrate surface through a source outlet 154 , and a processing fluid may be applied to the substrate surface through a source inlet 156 .
[0074] In another embodiment, the application of the IPA/N 2 157 and the processing fluid in addition to the application of the vacuum 158 to remove the processing fluid and the IPA/N 2 157 from the substrate surface 102 a can generate the fluid meniscus 116 . The fluid meniscus 116 may be a fluid layer defined between the proximity head 110 ′ and the substrate surface that can be moved across a substrate surface 102 in a stable and controllable manner. In one embodiment, the fluid meniscus 116 may be defined by a constant application and removal of the processing fluid. The fluid layer defining the fluid meniscus 116 may be any suitable shape and/or size depending on the size, number, shape, and/or pattern of the source inlets 156 , source outlets 154 , and source inlets 152 .
[0075] In addition, any suitable flow rates of the vacuum, IPA/N 2 , vacuum, and the processing fluid may be used depending on the type of fluid meniscus desired to be generated. In yet another embodiment, depending on the distance between the proximity head 110 ′ and the substrate surface, the IPA/N 2 may be omitted when generating and utilizing the fluid meniscus 116 . In such an embodiment, the proximity head 110 ′ may not include the source inlet 158 and therefore only the application of the processing fluid by the source inlet 156 and the removal of the processing fluid by the source outlet 154 generates the fluid meniscus 116 .
[0076] In other embodiments of the proximity head 110 ′, the processing surface of the proximity head 110 ′ (the region of the proximity head where the source inlets and source outlets are located) may have any suitable topography depending on the configuration of the fluid meniscus 116 to be generated. In one embodiment, the processing surface of the proximity head may be either indented or may protrude from the surrounding surface.
[0077] FIG. 4B shows a top view of a portion of a proximity head 110 ′ in accordance with one embodiment of the present invention. It should be appreciated that the configuration of the proximity head 110 ′ is exemplary in nature. Therefore, other configurations of proximity heads 110 ′ may be utilized to generate the fluid meniscus 116 as long as the processing fluid can be applied to a substrate surface and removed from the substrate surface to generate a stable fluid meniscus 116 on the substrate surface. In addition, as discussed above, other embodiments of the proximity head 110 ′ do not have to have the source inlet 156 when the proximity head 110 ′ is configured to generate the fluid meniscus without usage of N 2 /IPA.
[0078] In the top view of one embodiment, from left to right are a set of the source inlet 152 , a set of the source outlet 154 , a set of the source inlet 156 , a set of the source outlet 154 , and a set of the source inlet 152 . Therefore, as N 2 /IPA and processing chemistry are inputted into the region between the proximity head 110 ′ and the substrate surface, the vacuum removes the N 2 /IPA and the processing chemistry along with any fluid film and/or contaminants that may reside on the semiconductor wafer 102 . The source inlets 152 , the source inlets 156 , and the source outlets 154 described herein may also be any suitable type of geometry such as for example, circular opening, triangle opening, square opening, etc. In one embodiment, the source inlets 152 and 156 and the source outlets 154 have circular openings. It should be appreciated that the proximity head 110 ′ may be any suitable size, shape, and/or configuration depending on the size and shape of the fluid meniscus 116 desired to generated. In one embodiment, the proximity head may extend less than a radius of the substrate. In another embodiment, the proximity head may extend more than the radius of the substrate. In another embodiment, the proximity head may extend greater than a diameter of the substrate. Therefore, the size of the fluid meniscus may be any suitable size depending on the size of a substrate surface area desired to be processed at any given time. In addition, it should be appreciated that the proximity head 110 ′ may be positioned in any suitable orientation depending on the substrate processing operation such as, for example, horizontally, vertically, or any other suitable position in between. The proximity head 110 ′ may also be incorporated into a substrate processing system where one or more types of substrate processing operations may be conducted.
[0079] FIG. 4C illustrates an inlets/outlets pattern of a proximity head 110 ′ in accordance with one embodiment of the present invention. In this embodiment, the proximity head 110 ′ includes the source inlets 152 and 156 as well as source outlets 154 . In one embodiment, the source outlets 154 may surround the source inlets 156 and the source inlets 152 may surround the source outlets 154 .
[0080] FIG. 4D illustrates another inlets/outlets pattern of a proximity head 110 ′ in accordance with one embodiment of the present invention. In this embodiment, the proximity head 110 ′ includes the source inlets 152 and 156 as well as source outlets 154 . In one embodiment, the source outlets 154 may surround the source inlets 156 and the source inlets 152 may at least partially surround the source outlets 154 .
[0081] FIG. 4E illustrates a further inlets/outlets pattern of a proximity head 110 ′ in accordance with one embodiment of the present invention. In this embodiment, the proximity head 110 ′ includes the source inlets 152 and 156 as well as source outlets 154 . In one embodiment, the source outlets 154 may surround the source inlets 156 . In one embodiment, the proximity head 110 ′ does not include source inlets 152 because, in one embodiment, the proximity head 110 ′ is capable of generating a fluid meniscus without application of IPA/N 2 . It should be appreciated that the above described inlets/outlets patterns are exemplary in nature and that any suitable type of inlets/outlets patterns may be used as long as a stable and controllable fluid meniscus can be generated. In one embodiment, depending on how close the proximity head is to the surface being processed, IPA may not be utilized and only processing fluid inlets and vacuum outlets can be used to generate the fluid meniscus. Such an embodiment is described in further detail in reference to U.S. application Ser. No. 10/882,835 entitled “Method And Apparatus For Processing Wafer Surfaces Using Thin, High Velocity Fluid Layer” which is hereby incorporated by reference in its entirety.
[0082] For additional information about the proximity vapor clean and dry system, reference can be made to an exemplary system described in the U.S. Pat. No. 6,488,040, issued on Dec. 3, 2002, having inventors John M. de Larios, Mike Ravkin, Glen Travis, Jim Keller, and Wilbur Krusell, and entitled “C APILLARY P ROXIMITY H EADS FOR S INGLE W AFER C LEANING AND D RYING .” This U.S. Patent Application, which is assigned to Lam Research Corporation, the assignee of the subject application, is incorporated herein by reference.
[0083] For additional information with respect to the proximity head, reference can be made to an exemplary proximity head, as described in the U.S. Pat. No. 6,616,772, issued on Sep. 9, 2003, having inventors John M. de Larios, Mike Ravkin, Glen Travis, Jim Keller, and Wilbur Krusell, and entitled “M ETHODS FOR WAFER PROXIMITY CLEANING AND DRYING .” This U.S. Patent Application, which is assigned to Lam Research Corporation, the assignee of the subject application, is incorporated herein by reference.
[0084] For additional information about top and bottom menisci, reference can be made to the exemplary meniscus, as disclosed in U.S. patent application Ser. No. 10/330,843, filed on Dec. 24, 2002, having inventor Carl Woods, and entitled “M ENISCUS, V ACUUM, IPA V APOR, D RYING M ANIFOLD .” This U.S. Patent Application, which is assigned to Lam Research Corporation, the assignee of the subject application, is incorporated herein by reference.
[0085] For additional information about top and bottom menisci, vacuum, and IPA vapor, reference can be made to the exemplary system, as disclosed in U.S. patent application Ser. No. 10/330,897, filed on Dec. 24, 2002, having inventor Carl Woods, and entitled “S YSTEM FOR S UBSTRATE P ROCESSING WITH M ENISCUS, V ACUUM, IPA V APOR, D RYING M ANIFOLD .” This U.S. Patent Application, which is assigned to Lam Research Corporation, the assignee of the subject application, is incorporated herein by reference.
[0086] For additional information about proximity processors, reference can be made to the exemplary processor, as disclosed in U.S. patent application Ser. No. 10/404,270, filed on Mar. 31, 2003, having inventors James P. Garcia, Mike Ravkin, Carl Woods, Fred C. Redeker, and John M. de Larios, and entitled “V ERTICAL P ROXIMITY P ROCESSOR .” This U.S. Patent Application, which is assigned to Lam Research Corporation, the assignee of the subject application, is incorporated herein by reference.
[0087] For additional information about front and back menisci, reference can be made to the exemplary dynamic meniscus, as disclosed in U.S. patent application Ser. No. 10/404,692, filed on Mar. 31, 2003, having inventors James P. Garcia, John M. de Larios, Michael Ravkin, and Fred C. Redeker, and entitled “M ETHODS AND S YSTEMS FOR P ROCESSING A S UBSTRATE U SING A D YNAMIC L IQUID M ENISCUS .” This U.S. Patent Application, which is assigned to Lam Research Corporation, the assignee of the subject application, is incorporated herein by reference.
[0088] For additional information about meniscus, reference can be made to the exemplary dynamic liquid meniscus, as disclosed in U.S. patent application Ser. No. 10/603,427, filed on Jun. 24, 2003, having inventors Carl A. Woods, James P. Garcia, and John M. de Larios, and entitled “M ETHODS AND S YSTEMS FOR P ROCESSING A BEVEL E DGE S UBSTRATE U SING A D YNAMIC L IQUID M ENISCUS .” This U.S. Patent Application, which is assigned to Lam Research Corporation, the assignee of the subject application, is incorporated herein by reference.
[0089] For additional information about proximate cleaning and/or drying, reference can be made to the exemplary wafer process, as disclosed in U.S. patent application Ser. No. 10/606,022, filed on Jun. 24, 2003, having inventors John M. Boyd, John M. de Larios, Michael Ravkin, and Fred C. Redeker, and entitled “S YSTEM AND M ETHOD FOR I NTEGRATING I N -S ITU M ETROLOGY WITHIN A W AFER P ROCESS .” This U.S. Patent Application, which is assigned to Lam Research Corporation, the assignee of the subject application, is incorporated herein by reference.
[0090] For additional information about depositing and planarizing thin films of semiconductor substrates, reference can be made to the exemplary apparatus and method, as disclosed in U.S. patent application Ser. No. 10/607,611, filed on Jun. 27, 2003, having inventors John Boyd, Yezdi N. Dordi, and John M. de Larios, and entitled “A PPARATUS AND M ETHOD FOR D EPOSITING AND P LANARIZING T HIN F ILMS OF S EMICONDUCTOR W AFERS .” This U.S. Patent Application, which is assigned to Lam Research Corporation, the assignee of the subject application, is incorporated herein by reference.
[0091] For additional information about cleaning a substrate using megasonic cleaning, reference can be made to the exemplary method and apparatus, as disclosed in U.S. patent application Ser. No. 10/611,140, filed on Jun. 30, 2003, having inventors John M. Boyd, Mike Ravkin, Fred C. Redeker, and John M. de Larios, and entitled “M ETHOD AND A PPARATUS FOR C LEANING A S UBSTRATE U SING M EGASONIC P OWER .” This U.S. Patent Application, which is assigned to Lam Research Corporation, the assignee of the subject application, is incorporated herein by reference.
[0092] For additional information about proximity brush cleaning, reference can be made to the exemplary proximity brush, as disclosed in U.S. patent application Ser. No. 10/742,303, filed on Dec. 18, 2003, having inventors John M. Boyd, Michael L. Orbock, and Fred C. Redeker, and entitled “P ROXIMITY B RUSH U NIT A PPARATUS AND M ETHOD .” This U.S. Patent Application, which is assigned to Lam Research Corporation, the assignee of the subject application, is incorporated herein by reference.
[0093] Various proximity heads and methods of using the proximity heads are described in co-owned U.S. patent application Ser. No. 10/834,548 filed on Apr. 28, 2004 and entitled “A PPARATUS AND M ETHOD FOR P ROVIDING A C ONFINED L IQUID FOR I MMERSION L ITHOGRAPHY ,” which is a continuation in part of U.S. patent application Ser. No. 10/606,022, filed on Jun. 24, 2003 and entitled “S YSTEM A ND M ETHOD F OR I NTEGRATING I N -S ITU M ETROLOGY W ITHIN A W AFER P ROCESS .” Additional embodiments and uses of the proximity head are also disclosed in U.S. patent application Ser. No. 10/404,692, filed on Mar. 31, 2003, entitled “M ETHODS AND S YSTEMS FOR P ROCESSING A S UBSTRATE U SING A D YNAMIC L IQUID M ENISCUS .” Additional information with respect to proximity cleaning can be found in U.S. patent application Ser. No. 10/817,355 filed on Apr. 1, 2004 entitled “S UBSTRATE P ROXIMITY P ROCESSING S TRUCTURES AND M ETHODS FOR U SING AND M AKING THE S AME ,” U.S. patent application Ser. No. 10/817,620 filed on Apr. 1, 2004 entitled “S UBSTRATE M ENISCUS I NTERFACE AND M ETHODS FOR O PERATION ,” and U.S. patent application Ser. No. 10/817,133 filed on Apr. 1, 2004 entitled “P ROXIMITY M ENISCUS M ANIFOLD .” The aforementioned patent applications are hereby incorporated by reference in their entirety.
[0094] Additional embodiments and uses of the proximity head are also disclosed in U.S. patent application Ser. No. 10/330,897, filed on Dec. 24, 2002, entitled “System for Substrate Processing with Meniscus, Vacuum, IPA vapor, Drying Manifold” and U.S. patent application Ser. No. 10/404,270, filed on Mar. 31, 2003, entitled “Vertical Proximity Processor,” U.S. patent application Ser. No. 10/817,398 filed on Apr. 1, 2004 entitled “Controls of Ambient Environment During Wafer Drying Using Proximity Head,” U.S. Pat. No. 6,488,040, issued on Dec. 3, 2002, entitled “Capillary Proximity Heads For Single Wafer Cleaning And Drying,” and U.S. Pat. No. 6,616,772, issued on Sep. 9, 2003, entitled “Methods For Wafer Proximity Cleaning And Drying.” Still further, additional embodiments and uses of the proximity head are described in U.S. patent application Ser. No. 10/883,301 entitled “Concentric Proximity Processing Head,” and U.S. patent application Ser. No. 10/882,835 entitled “Method and Apparatus for Processing Wafer Surfaces Using Thin, High Velocity Fluid Layer.” Further embodiments and uses of the proximity head are further described in U.S. patent application Ser. No. 10/957,260 entitled “Apparatus And Method For Processing A Substrate,” U.S. patent application Ser. No. 10/956,799 entitled “Apparatus And Method For Utilizing A Meniscus In Substrate Processing” and U.S. patent application Ser. No. 10/957,384 entitled “Phobic Barrier Meniscus Separation And Containment.” The aforementioned patent applications are hereby incorporated by reference in their entirety.
[0095] Although the foregoing invention has been described in some detail for purposes of clarity of understanding, it will be apparent that certain changes and modifications may be practiced within the scope of the appended claims. For example, the embodiments of the present invention can be implemented to clean any substrate having varying sizes and shapes such as those employed in the manufacture of semiconductor devices, flat panel displays, hard drive discs, flat panel displays, and the like. Additionally, the present embodiments are to be considered as illustrative and not restrictive, and the invention is not to be limited to the details given herein, but may be modified within the scope and equivalents of the appended claims.
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A method for cleaning a substrate is provided. The method includes receiving the substrate using a carrier that forms a circular opening, the substrate being positioned in the circular opening of the carrier. The holding of the substrate enables exposure of both a first side and a second side of the substrate at a same time. Then, moving the substrate along a direction, and while moving the substrate: (i) applying a chemistry onto the first side of the substrate, where the first side of the substrate having material to be removed; (ii) forming a fluid meniscus against the second side of the substrate at a location that is opposite a location onto which the chemistry is applied; and (iii) applying megasonic energy to the fluid meniscus while the fluid meniscus is applied against the second side. The megasonic energy increases mass transport of the chemistry to enhance removal of the material to be removed from the first side.
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BACKGROUND AND SUMMARY
[0001] Vehicles having internal combustion engines typically utilize intake manifold vacuum for power accessories and facilitating certain emission control activities. In particular, engines utilize intake manifold vacuum to draw stored fuel vapors from a carbon canister or other vapor storage device. In this way, fuel vapors generated in the fuel tank can be contained and then used in the engine to reduce emission of such vapors.
[0002] Various types of engine operation can affect the level of vacuum in the intake manifold, such as variation in the engine load, engine air-fuel ratio, engine valve timing and/or lift, cylinder deactivation, and engine combustion mode (such as homogenous charge compression ignition operation, HCCI), for example. Under some conditions, such engine operation can reduce available vacuum below that needed to purge sufficient fuel vapors. Thus, some approaches adjust engine operation (e.g., by adjusting air-fuel ratio, valve timing, throttling, etc.) to manage the intake manifold vacuum, while others may utilize a vacuum pump to generate additional vacuum when needed.
[0003] However, the inventors herein have recognized several issues with such approaches. While adjusting engine operation may be appropriate under some conditions, it may also result in lost fuel savings due to an inability to operating in a more efficient combustion mode. For example, due to a need to purge fuel vapors, the engine may operate in more efficient combustion modes, such as HCCI, less often than otherwise possible. Also, throttling to generate vacuum may increase engine pumping work. Further, utilizing external vacuum pumps or other such devices can also increase parasitic losses and thus degrade fuel economy, in addition to increasing cost.
[0004] The inventors herein have further recognized that it may be beneficial to push the vapors from the canister into the intake manifold using exhaust pressure, rather than, or in addition to, pulling the vapors using manifold vacuum. In this way, it may be possible to enable additional operation at lower vacuum levels, thus extending more fuel efficient combustion modes, for example.
[0005] Further, increased temperature from the exhaust gas may enable more efficient purging under some conditions. Specifically, the higher temperature of the exhaust gas (compared with fresh air) may help purge fuel vapors from a vapor storage device, such as a charcoal canister since vapor purging is an endothermic reaction. In other words, the charcoal canister normally cools when fresh air is used for purging. Using at least some exhaust gas for purging would raise the temperature and thus enable purging with a smaller volume of gas, further reducing the need for intake manifold vacuum.
[0006] Note that there are various sources of exhaust gas that may be used to purge fuel vapors, such as exhaust gas recirculation gas, or other exhaust gas.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 is a schematic diagram of an engine;
[0008] FIGS. 2-4 are various alternative examples of a system configuration for utilizing exhaust gas to purge fuel vapors; and
[0009] FIG. 5 is a flowchart of an example method to control system operation.
DETAILED DESCRIPTION
[0010] FIG. 1 shows an example engine 24 as a direct injection gasoline engine with a spark plug; however, engine 24 may be a port injection gasoline engine, or a diesel engine without a spark plug, or another type of engine. Internal combustion engine 24 may include a plurality of cylinders, one cylinder of which is shown in FIG. 1 , which is controlled by electronic engine controller 48 . Engine 24 includes combustion chamber 29 and cylinder walls 31 with piston 35 positioned therein and connected to crankshaft 39 . Combustion chamber 29 is shown communicating with intake manifold 43 and exhaust manifold 47 via respective intake valve 52 and exhaust valve 54 . While only one intake and one exhaust valve are shown, the engine may be configured with a plurality of intake and/or exhaust valves.
[0011] Engine 24 is further shown configured with an exhaust gas recirculation (EGR) system configured to supply exhaust gas to intake manifold 43 from exhaust manifold 47 via EGR passage 130 . The amount of exhaust gas supplied by the EGR system can be controlled by EGR valve 134 . Further, the exhaust gas within EGR passage 130 may be monitored by an EGR sensor 132 , which can be configured to measure temperature, pressure, gas concentration, etc. Under some conditions, the EGR system may be used to regulate the temperature of the air and fuel mixture within the combustion chamber, thus providing a method of controlling the timing of autoignition for HCCI combustion.
[0012] In some embodiments, as shown in FIG. 1 , variable valve timing may be provided by variable cam timing (VCT); however other methods may be used such as electrically controlled valves. While in this example, independent intake cam timing and exhaust cam timing are shown, variable intake cam timing may be used with fixed exhaust cam timing, or vice versa. Also, various types of variable valve timing may be used, such as the hydraulic vane-type actuators 53 and 55 receiving respective cam timing control signals VCTE and VCTI from controller 48 . Cam timing (exhaust and intake) position feedback can be provided via comparison of the crank signal PIP and signals from respective cam sensors 50 and 51 .
[0013] In some embodiments, cam actuated exhaust valves may be used with electrically actuated intake valves, if desired. In such a case, the controller can determine whether the engine is being stopped or pre-positioned to a condition with the exhaust valve at least partially open, and if so, hold the intake valve(s) closed during at least a portion of the engine stopped duration to reduce communication between the intake and exhaust manifolds. In addition, intake manifold 43 is shown communicating with optional electronic throttle 125 .
[0014] Engine 24 is also shown having fuel injector 65 coupled thereto for delivering liquid fuel in proportion to the pulse width of signal FPW from controller 48 directly to combustion chamber 29 . As shown, the engine may be configured such that the fuel is injected directly into the engine cylinder, which is known to those skilled in the art as direct injection. Distributorless ignition system 88 provides ignition spark to combustion chamber 29 via spark plug 92 in response to controller 48 . Universal Exhaust Gas Oxygen (UEGO) sensor 76 is shown coupled to exhaust manifold 47 upstream of catalytic converter 70 . Exhaust gas sensor 76 is shown coupled to exhaust manifold 48 upstream of catalytic converter 70 . The signal from sensor 76 can be used to advantage during feedback air/fuel control in a conventional manner to maintain average air/fuel at stoichiometry during the stoichiometric homogeneous mode of operation.
[0015] Controller 48 is shown in FIG. 1 as a conventional microcomputer including: microprocessor unit 102 , input/output ports 104 , and read-only memory 106 , random access memory 108 , keep alive memory 110 , and a conventional data bus. Controller 48 is shown receiving various signals from sensors coupled to engine 24 , in addition to those signals previously discussed, including: engine coolant temperature (ECT) from temperature sensor 112 coupled to cooling sleeve 114 ; a pedal position sensor 119 coupled to an accelerator pedal; a measurement of engine manifold pressure (MAP) from pressure sensor 122 coupled to intake manifold 43 ; a measurement (ACT) of engine air charge temperature or manifold temperature from temperature sensor 117 ; and an engine position sensor from a Hall effect sensor 118 sensing crankshaft 39 position. In some embodiments, the requested wheel output can be determined by pedal position, vehicle speed, and/or engine operating conditions, etc. In one 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.
[0016] FIG. 1 shows engine 24 configured with an aftertreatment system comprising a catalytic converter 70 and a lean NOx trap 72 . In this particular example, the temperatures of catalytic converter 70 and/or NOx trap 72 may be measured by temperature sensors in the devices or in the exhaust manifold, or may be estimated based on operating conditions. Further, exhaust gas oxygen sensors may be arranged in exhaust passage 47 upstream and/or downstream of lean NOx trap 72 . Lean NOx trap 72 may include a three-way catalyst that is configured to adsorb NOx when engine 24 is operating lean of stoichiometry. The adsorbed NOx can be subsequently reacted with HC and CO and catalyzed when controller 48 causes engine 24 to operate in either a rich homogeneous mode or a near stoichiometric homogeneous mode such operation occurs during a NOx purge cycle when it is desired to purge stored NOx from the lean NOx trap, or during a vapor purge cycle to recover fuel vapors from fuel tank 160 and fuel vapor storage canister 164 via purge control valve 168 , or during operating modes requiring more engine power, or during operation modes regulating temperature of the emission control devices such as catalyst 70 or lean NOx trap 72 . It will be understood that various different types and configurations of emission control devices and purging systems may be employed.
[0017] As will be described in more detail herein, combustion in engine 24 can be of various types, depending on a variety of conditions. In one example, spark ignition (SI) may be used where the engine utilizes a sparking device to perform a spark so that a mixture of air and fuel combusts. In another example, homogeneous charge compression ignition (HCCI) may be used where a substantially homogeneous air and fuel mixture attains an autoignition temperature within the combustion chamber and combusts without requiring a spark from a sparking device. However, other types of combustion are possible. For example, the engine may operate in a spark assist mode, wherein a spark is used to initiate autoignition of an air and fuel mixture. In yet another example, the engine may operate in a compression ignition mode that is not necessarily homogeneous. It should be appreciated that the examples disclosed herein are non-limiting examples of the many possible combustion modes.
[0018] During SI mode, the temperature of intake air entering the combustion chamber may be near ambient air temperature and is therefore substantially lower than the temperature required for autoignition of the air and fuel mixture. Since a spark is used to initiate combustion in SI mode, control of intake air temperature may be more flexible as compared to HCCI mode. Thus, SI mode may be utilized across a broad range of operating conditions (such as higher or lower engine loads), however SI mode may produce different levels of emissions and fuel efficiency under some conditions compared to HCCI combustion.
[0019] In some conditions, during SI mode operation, engine knock may occur if the temperature within the combustion chamber is too high. Thus, under these conditions, engine operating conditions may be adjusted so that engine knock is reduced, such as by retarding ignition timing, reducing intake charge temperature, varying combustion air-fuel ratio, or combinations thereof.
[0020] During HCCI mode operation, the air/fuel mixture may be highly diluted by air and/or residuals (e.g. lean of stoichiometry), which results in lower combustion gas temperature. Thus, engine emissions may be substantially lower than SI combustion under some conditions. Further, fuel efficiency with autoignition of lean (or diluted) air/fuel mixture may be increased by reducing the engine pumping loss, increasing gas specific heat ratio, and by utilizing a higher compression ratio. During HCCI combustion, autoignition of the combustion chamber gas may be controlled so as to occur at a prescribed time so that a desired engine torque is produced. Since the temperature of the intake air entering the combustion chamber may be critical to achieving the desired autoignition timing, operating in HCCI mode at high and/or low engine loads may be difficult.
[0021] Controller 48 can be configured to transition the engine between a spark ignition (SI) mode and a homogeneous charge compression ignition (HCCI) mode based on operating conditions of the engine and/or related systems, herein described as engine operating conditions.
[0022] As described above with reference to FIG. 1 , engine 24 may include a fuel vapor purge system comprising fuel tank 160 , fuel vapor storage device 164 (which may be a charcoal canister), and purge control valve 168 fluidly coupled to intake manifold 43 . Further, as shown in FIG. 1 , exhaust gas may be routed to the purge system via system 172 . While FIG. 1 shows one example of utilizing exhaust gas in a fuel vapor purge system, various alternative examples are described herein with regard to FIGS. 2-4 .
[0023] Returning to FIG. 1 , some of the engine exhaust gas is routed through the charcoal canister and then back into the engine intake manifold. As described herein, such an approach may be used to enable purging of fuel vapors without regard to intake manifold vacuum levels. Further, it may enable more efficient purging with a lower volume of gas flow due to increased exhaust gas temperature compared with fresh air. Such an approach may be particularly suitable for HCCI operation, which may run extremely lean and/or with high amounts of EGR. Specifically, since HCCI engines may operate with larger amounts of EGR, it may be possible to enable larger amounts of exhaust to be used for purging the stored fuel vapors. Further, since HCCI exhaust temperature may be lower than exhaust temperature during spark ignition operation (SI) or other engine modes, this may lower the potential of excessive heat causing degradation to the charcoal canister. Note, however, that the use of exhaust gas, such as exhaust gas recirculation (EGR) gas, to aid purging is not limited to HCCI engine operation. For example, it may be used in with cylinder deactivation, camless valvetrains, engine boosting (supercharging and/or turbocharging), various forms of variable valve timing, and/or lean burn.
[0024] For systems in which only exhaust gas, such as EGR, is used for purging fuel vapors without fresh air, at least during some conditions, EGR tolerance and temperature limits of the storage device, e.g., charcoal canister, may be considered, alone or in combination. For example, if the charcoal canister can tolerate higher temperatures, then smaller amounts of hotter EGR can be used to purge the canister. Alternatively, if the EGR temperature is too high, the EGR may be cooled, so larger amounts of EGR can be used to purge the canister, and thus the engine's tolerance for EGR (combustion stability) may be considered.
[0025] Alternatively, if both fresh air and exhaust gas are used to purge fuel vapors, temperature of the canister may be regulated by adjusting the relative and/or absolute amounts of the fresh or exhaust gas, or combinations thereof. For example, depending on engine conditions (e.g. in HCCI or SI mode, higher vs lower load, etc.), different amounts of fresh air and/or exhaust gas may be used to purge fuel vapors.
[0026] Still another advantage of utilizing exhaust gas for purging fuel vapors is that it may be possible to purge vapors even during un-throttled (or lightly throttled) conditions. For example, a one-way valve, such as a reed valve, can utilize exhaust pressure pulsations to drive the flow, even if negative oscillations would otherwise reverse the flow directions.
[0027] In some embodiments, the internal combustion engine can be configured to operate in a plurality of purge states. For example, fuel vapors may be purged into all or a subset of engine cylinders operating in a particular combustion mode. Alternatively, the engine may be operated with different cylinders in different combustion modes, where fuel vapors are fed to all or a subset of cylinders or cylinder groups. Still other examples may be used, as described herein.
[0028] Referring now to FIG. 2 , an alternative embodiment is shown in which a fuel vapor storage and purging system is shown utilizing fresh air and exhaust gas. In this example, valves 168 and 216 are closed and valve 214 is open when the engine is off, to allow fuel vapors from the fuel tank to be captured by charcoal canister 164 , without building up excessive pressure in the tank. When the engine is running and purge of the charcoal canister is desired, valves 168 and 216 can be opened and valve 214 can be closed to route exhaust gas through passage 210 to canister 164 , and purge fuel vapors from canister 164 into intake manifold 43 . A one-way valve 212 is shown between the exhaust passage and fuel canister 164 for enabling exhaust gas to flow toward the canister (and to the intake manifold 43 ). Valve 212 may be any type of one-way valve, but in one example may be a reed-type valve to enable pressure buildup in the presence of pulsating intake and exhaust manifold pressures. Control valves 214 and 216 may be used to adjust the relative amount of fresh air and exhaust fed through the fuel vapor storage system, where valves 214 and 216 receive control signals from a controller, such as controller 48 (see FIG. 1 ). Control valve 168 may also be used to control when fuel vapors are fed to intake manifold 43 .
[0029] In the example of FIG. 2 , it may be possible to utilize a varying amount of exhaust gas and/or fresh air for purging fuel vapors to the engine, depending on operating conditions of the engine via respective control of valves 216 and 214 .
[0030] Referring now to FIG. 3 , still another alterative embodiment is shown in which a bypass passage 330 is shown for routing exhaust gas to the intake manifold without passing through canister 164 . A three way valve 310 may be used to route exhaust gas to one-way valve 212 or to passage 330 , or combinations thereof. In this way, it may be possible to enable addition exhaust gas recirculation (EGR) flexibility independent of fuel vapor purging operation. For example, EGR may be performed without fuel vapor purging, and vice versa via appropriate control of valve 310 .
[0031] Referring now to FIG. 4 , yet another alterative embodiment is shown in which an EGR passage 410 is shown separate from purging passage 210 . Further, optionally coolers ( 420 and 422 ) may be placed in one or both of passages 210 and 410 to cool the exhaust gas. It is understood that the location or sequence of components may be varied, for example the locations of coolers 420 and 422 relative to valves 134 , 212 , and 216 may be different than that shown in FIG. 4 . Also, one or more coolers may be used in the embodiments described in FIGS. 2 and 3 .
[0032] FIG. 5 shows an example routine describing control of a vehicle engine and fuel vapor purging system. Note that the example control and estimation routines included herein can be used with various engine system configurations and that the specific routines described herein 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 features and advantages of the example embodiments described herein, but is provided for ease of illustration and description. One or more of the illustrated steps or functions may be repeatedly performed depending on the particular strategy being used. Further, the described steps may graphically represent code to be programmed into the computer readable storage medium in controller 48 as described above, during fuel vapor purging operation.
[0033] Referring now to FIG. 5 , an example routine is described for controlling system operation. Specifically, in 510 , the routine determines whether the engine should purge fuel vapors from a fuel vapor storage system. If so, the routine continues to 512 to determine whether the engine can tolerate exhaust gas recirculation (EGR). This determination may include consideration of whether a lean exhaust gas is present, such as based on exhaust gas sensor 76 , or based on input from other sensors. For example, the engine may be more likely to tolerate EGR when running significantly lean, because the exhaust gas contains more oxygen. For example, the lean exhaust gas may be generated by lean homogeneous or lean stratified combustion in the cylinders, or by a mixture of fuel cut-out operation in some cylinders and combustion in other cylinders. Also, rather than identifying the exhaust air-fuel ratio, the routine may also identify whether the engine is in a lean combustion mode, such as HCCI operation, for example.
[0034] If the answer to 512 is yes, the routine continues to 514 to determine whether the exhaust gas is within a temperature threshold to feed to a fuel vapor storage canister, such as canister 164 . The temperature may be read from a sensor or estimated, as noted above herein. For example, if the exhaust gas temperature is too high (e.g., above a threshold), the routine may proceed to 516 in which only fresh air is used to purge fuel vapors, rather than using exhaust gas. Likewise, if the answer to 512 is no, the routine may also proceed to 516 .
[0035] Otherwise, when the answer to 514 is yes, the routine proceeds to 518 to determine whether the measured or inferred purging gas is within a desired temperature range. For example, in the example where a mixture of fresh air and exhaust gas is fed to a fuel vapor storage and purging system, the routine may identify whether the mixture fed to the system is within a desired temperature range for improved purging, where the desired range may vary with operating conditions such as the level of canister loading, fuel tank pressure, canister temperature, and/or others. Alternatively, the routine may monitor the measured or inferred canister temperature and determine whether it is within threshold range.
[0036] The desired temperature range may be based on various other factors, such as exhaust air-fuel ratio, fuel tank temperature, combustion mode, canister fill level, fuel tank level, and/or combinations thereof.
[0037] If the temperature is too high, the routing may proceed to 520 to increase the fresh air amount for purging and/or decrease the exhaust gas amount for purging fuel vapors. Alternatively, if the temperature is too low, the routing may proceed to 522 to decrease the fresh air amount for purging and/or increase the exhaust gas amount for purging fuel vapors. In either 520 and/or 522 , for example, the routine may adjust a vent valve and/or EGR valve such as valves 214 and 216 to vary the mixture, and thus the temperature, of gas fed to the canister. Alternatively, the routine may adjust a single valve that adjusts the amount of exhaust gas fed to a canister, such as valve 310 in FIG. 3 . In addition, the routine may also adjust the amount of purge gas fed to the intake manifold based on operating conditions via valve 168 , for example, in 524 .
[0038] In this way, it is possible to advantageously utilize exhaust gas, such as exhaust gas recirculation, to improve purging performance and reduce reliance on intake manifold vacuum. Further, it is possible to take advantage of lean exhaust gas (which typically results in reduced intake manifold vacuum) by utilizing the excess oxygen and increased temperature to improve purging of fuel vapors from a fuel vapor storage system such as a charcoal canister.
[0039] Note that in the example where exhaust gas is used to carry fuel purge vapor to the engine, fuel injection, sparking timing, etc. may be adjusted based on a level of fuel vapor in the gas, as well as the exhaust air-fuel ratio.
[0040] It will be appreciated that the configurations and routines disclosed herein are exemplary in nature, and that these specific embodiments are not to be considered in a limiting sense, because numerous variations are possible. For example, the above technology can be applied to V-6, I-4, I-6, V-8, V-10, V-12, opposed 4, and other engine types. The subject matter of the present disclosure includes all novel and nonobvious combinations and subcombinations of the various systems and configurations, and other features, functions, and/or properties disclosed herein.
[0041] The following claims particularly point out certain combinations and subcombinations regarded as novel and nonobvious. These claims may refer to “an” element or “a first” element or the equivalent thereof. Such claims should be understood to include incorporation of one or more such elements, neither requiring nor excluding two or more such elements. Other combinations and subcombinations of the disclosed features, functions, elements, and/or properties may be claimed through amendment of the present claims or through presentation of new claims in this or a related application. Such claims, whether broader, narrower, equal, or different in scope to the original claims, also are regarded as included within the subject matter of the present disclosure.
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A system for a vehicle, comprising of an engine, and a fuel vapor storage system coupled to the engine configured to store and release fuel vapors, the system further configured to route exhaust gas from the engine to the vapor storage system and where adsorbed vapors are released into the exhaust gas before the exhaust gas is re-inducted into the engine to be burned.
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CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is related to; 1) U.S. patent application Ser. No. 11/749,852, entitled “Super-Hydrophobic Water Repellent Powder”, filed May 17, 2007; 2) U.S. patent application Ser. No. 10/900,249, entitled “Composite, Nano-Structured, Super-Hydrophobic Material”, filed Jul. 27, 2004; 3) U.S. patent application Ser. No. 11/463,964, entitled “Composite, Nano-Structured, Super-Hydrophobic Material”, filed Aug. 11, 2006; and 4) U.S. patent application Ser. No. 11/777,486, entitled “Superhydrophobic Diatomaceous Earth”, filed Jul. 13, 2007; all herein incorporated by reference.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH
[0002] This invention was made with United States Government support under Contract No. DE-AC05-00OR22725 between the United States Department of Energy and U.T. Battelle, LLC. The United States Government has certain rights in this invention.
BACKGROUND OF THE INVENTION
[0003] Both superhydrophobic (SHB) and superhydrophilic (SHL) powders can be manufactured by controlling surface texture and chemistry at the nanoscale and microscale. Stable superhydrophobic surfaces with advancing and receding water droplet contact angles in excess of 150° as well as stable superhydrophilic surfaces with contact angles less than 5° are possible. In the case of the superhydrophilic powder, nearly instantaneous water wetting is observed as well as uniform water sheeting across the surface during drying. Applying these powders to fabric transfers the properties of the powder to the fabric.
[0004] The phenomenon of superhydrophobicity, inspired from the “lotus leaf effect,” has led to the technological development of superhydrophobic materials and coatings, which consist of a hydrophobic, rough surface with low surface energy. The lotus leaf effect is revealed from a study of the surfaces of lotus leaves. The surface of a lotus leaf is covered with countless miniature protrusions coated with a waxy layer. This waxy layer acts as a multifunctional interface between the leaf and its environment, influencing the airflow and light reflection, and imparting very high water repellency to the leaf to cause water to roll over its surface as small droplets. These hydrophobic microscopic topographical features minimize the area of contact of water with the leaf surface, thereby keeping the water in contact mainly with air. Hence the water on the leaf surface substantially retains the droplet shape it would have in air. One of the methods of measuring the water repellency of a surface is to measure contact angle of a water drop with the surface. Higher contact angles imply enhanced hydrophobic surface and greater water repellency. Smooth hydrophobic surfaces tend to have contact angles up to 110° and 120° for certain Teflon materials, but the rough microstructures present on the lotus leaf result in contact angles as high as 170°, thereby imparting to the surface enhanced superhydrophobic properties.
[0005] Since much of the superior water-repellency of the lotus leaf derives from the structural (microscopic features) and chemical (waxy) properties, extensive research has been carried out to develop techniques to create such microscopic features and wax-like properties on artificial surfaces. For example, the development of superhydrophobic materials and surfaces have been investigated for practical and technical applications such as water repelling and self-cleaning coatings for fabrics and textiles; coatings that impart wrinkle resistance to fabric; self-cleaning coatings for ovens, electric ranges, filters, and window blinds; anti-soiling coatings for titanium surfaces, transparent substrates, painted surfaces, wall-papers, and washing-machine tubs; water-repellant and self-cleaning coatings for automobile glass, optics, laser glass, exterior walls of buildings, paints; anti-corrosion coatings; and coatings for biomedical applications. Typically, artificial hydrophobic surfaces must have contact angles greater than 150° to acquire the “super” prefix.
[0006] A variety of approaches have been followed in order to create a hydrophobic surface with microrough features to impart superhydrophobic properties to the surface. Hydrophobic materials developed thus far are based on polymeric systems such as poly (phytanyl methacrylate), a copolymer of 2-isopropenyl-2oxazoline and methyl methacrylate, other acrylic-siloxane based systems, silica and aluminum based polymer systems, a hybrid hydrophobic material comprising electro-deposited nickel and organofluoro polymeric components on a glass substrate, and polymers comprising one or more fluoro groups. The microroughness on the surface of coatings comprising the foregoing hydrophobic materials was created by employing techniques such as dispersing particles made of TiO 2 in a hydrophobic polymer for photocatalytic assistance in formation of self-cleaning surfaces, dispersing polymeric and metallic particles, chemical micropatterning, self-assembly, photolithography, capillary force lithography, and soft lithography. Some of these surface coatings can also be applied to fabric using various methods.
[0007] A major problem in making water repellant superhydrophobic fabrics has been the lack of an easy and inexpensive way of making these fabrics. Typically, water repellant fabrics have very poor quality (i.e. water is poorly repelled and doesn't really form an air layer between the water and raw fiber as is the case for truly superhydrophobic fibers). The higher quality superhydrophobic materials tend to be very expensive and structurally not amenable to coating fibers and fabrics. By using an inexpensive, highly porous, nanostructured superhydrophobic powder, many of the major problems are overcome.
[0008] Superhydrophobic, superrepellant and self-cleaning fibers could bring a large number of benefits to the textile industry including the potential to replace conventional fluorochemical based finishing products used for providing water repellency or low friction to textile surfaces. The super-repellent textile materials can be extremely important when suits protective against chemical and biological weapon are designed. Moreover, such fiber surfaces can be thought of as being liquid superconductors with superhydrophobic fibers transporting fluids essentially on a bed of air. When water is passed over such a surface it will exhibit elements of a self-cleaning process. It is clear that superhydrophobic fibers and superhydrophobic-like substrates will revolutionize and extend the capability of many textile-based applications as well as create new product markets. Enhanced properties of many standard textile assemblies is expected, for example, a combination of hydrophilic fibers with superhydrophobic fibers will produce smart or extreme textile assemblies that will push moisture away from the body very rapidly and pull it through the fabric for quick drying.
[0009] Numerous hydrophobic materials have been developed, including PTFE, nylon, glass fibers, polyethersulfone and aggregates having hydrophobic properties. One such material is disclosed in U.S. Pat. No. 3,562,153, to Tully et al. The oil absorbent compositions of the Tully et al. patent are obtained by treating a liquid absorbent material, which may be particulate, granular or fibrous in nature, with a colloidal metal or metalloid oxide which is chemically bonded to an organosilicon compound to render the metal or metalloid oxide hydrophobic. The hydrophobic oxide-treated absorbent composition is contacted with the oil-contaminated water and selectively removes the oil therefrom. The oil absorbent composition of Tully et al. is reported to have excellent water repellency, thus enabling it to maintain its oil absorbent efficiency for long immersion periods.
[0010] U.S. Pat. No. 4,474,852, to Craig, combines ideas of several prior art patents (U.S. Pat. Nos. 3,567,492; 3,672,945; 3,973,510; 3,980,566; 4,148,941; and 4,256,501). According to Craig, hydrophobic composites having superior water repellency are obtainable by depositing on a particulate and granular core material an adherent first coat which comprises a film-forming polyurethane and asphalt, as an optional additive, and applying to the thus coated core material a second coat comprising a hydrophobic colloidal oxide such as, for example, hydrophobic fumed silica. Craig teaches that the adherent first coat should not exceed 1 weight percentage of the total dry aggregate weight while the second coat is between 0.025 and 0.25 weight percentage of this total weight. Further according to the teachings of Craig, hydrophobic composites prepared in this manner not only prevent water from adhering to the surfaces of the individual composite particles, but also from entering the interstitial spaces of the aggregates of the composites.
[0011] WO 03/044124 also discloses a method of preparing hydrophobic aggregates, which is based on the teachings of Craig (U.S. Pat. No. 4,474,852). According to the teachings of WO 03/044124, the hydrophobic aggregates disclosed in U.S. Pat. No. 4,474,852 are not satisfactory as they do not withstand water pressure higher than 2-3 centimeters.
[0012] In a search for a method of producing hydrophobic aggregates with improved water-repellency and oil absorbency performance and improved durability under higher water pressures, it was concluded, according to the teachings of WO 03/044124, that an improved method of preparing hydrophobic aggregates, as compared with the teachings of Craig, should include changes relating to the compositions of the first and second coat and the relative amounts thereof, to the temperature in the various process steps and to the mixing rate during the course of preparation. Hence, the method disclosed in WO 03/044124 includes depositing on a particulate or granulate core material an adherent first coat which comprises a film-forming agent such as polyurethane and optionally a gluing agent such as liquid asphalt, and applying to the thus coated core material a second coat which comprises a hydrophobic fumed silicate or any other superhydrophobic powder. According to the teachings of WO 03/044124, the adherent first coat constitutes about 1-2 weight percentages of the total dry aggregate weight while the second coat constitutes more than 5 weight percentages of this total weight. Further according to the teachings of WO 03/044124, such hydrophobic aggregate is capable of holding a water pressure of up to 20-30 cm.
[0013] Although WO 03/044124 teaches the use of superhydrophobic powders other than hydrophobic fumed silica, this reference neither specifies nor exemplifies such a superhydrophobic powder. This reference also fails to demonstrate any performance of the hydrophobic aggregates disclosed therein with regard to both, water repellency and its behavior under high water pressures. Furthermore, it is well known in the art that using such a large amount of hydrophobic fumed silica as the second coat, as taught by WO 03/044124, reduces the cost-effectiveness as well as the simplicity of the process.
[0014] In addition, hydrophobic fumed silica, as well as other metal oxides treated with organosilicon compounds, such as those disclosed in the Craig patent, are characterized as acidic substances, aggregates coated by such materials are susceptible to reactions with alkaline reagents such as detergents. This feature limits the use of such aggregates in applications where detergents may be in contact with the hydrophobic aggregates, such as, for example, top-coatings of various surfaces.
BRIEF SUMMARY OF THE INVENTION
[0015] This invention uses both superhydrophilic and superhydrophobic powders to modify synthetic fibers in such a way as to make them extremely water attractive or repellant. Using both superhydrophilic (SHL) and superhydrophobic (SHB) powder, made with a special composition of sodium borosilicate “EX24” glass or diatomaceous earth, non-water-repellant fabrics were converted to water repellant superhydrophobic fabrics, and vice-versa, by electrostatic spray coating and chemical bonding. This was demonstrated on two types of non-woven fabrics and natural cotton fabrics using both superhydrophilic and superhydrophobic powder. The non-woven fabrics were composed of synthetic polymers.
[0016] The invention includes a superhydrophilic fabric having a superhydrophilic powder disposed on the fabric, wherein the superhydrophilic powder further comprises at least one material selected from the group consisting of sodium borosilicate glass and porous diatomaceous earth. The powder material has a contiguous interpenetrating structure with a plurality of spaced apart nanostructured surface features. The superhydrophilic powder can further have at least one superhydrophobic material selected from the group consisting of perfluorinated organics, fluorinated organics, and self-assembled monolayers, thereby switching the powder to a superhydrophobic powder for disposing on fabric.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] FIG. 1 is a photograph of a superhydrophobic material of this invention.
DETAILED DESCRIPTION OF THE INVENTION
[0018] Both superhydrophilic (SHL) and superhydrophobic (SHB) powders, including powder made from specially formulated sodium borosilicate glass and powder made from diatomaceous earth, are applied to fabric for attracting and repelling water. Examples and further explanation of these powders is found in co-pending U.S. patent application Ser. No. 11/749,852, filed May 17, 2007, and U.S. patent application Ser. No. 11/777,486, entitled “Superhydrophobic Diatomaceous Earth”, filed Jul. 13, 2007, both herein incorporated by reference. The superhydrophilic and superhydrophobic powders converted non-water-repellant fabrics to water repellant superhydrophobic fabrics, and vice-versa, by electrostatic spray coating and chemical bonding the SHL and SHB powders to the fabric. This was demonstrated on two types of non-woven fabrics and an all cotton fabric using both superhydrophilic and superhydrophobic powder. The non-woven fabrics were composed of synthetic polymers.
[0019] The superhydrophilic glass powder is formed from an interpenetrating blend or composite of a plurality of materials where at least one material protrudes from the other materials at the surface of the particle after the removal of at least some of one or more materials. The glass powder has a plurality of pores that permit flow of a gas or a liquid through the powder. Each material is contiguous and the different materials form an interpenetrating structure. The particles that make up the glass powder are in the range of about 100 nanometers to about 10 microns in size and have protrusions that are small relative to the size of the particles such that a plurality of protrusions is present on a given particle. The SHB particles have at least one hydrophobic material included in the plurality of materials, including the protruding material, or the particle is coated with a hydrophobic material such that the surface retains the general topography of protrusions from the surface of the particles and the surface is hydrophobic. The particles have pores, and a portion of these pores have connectivity through the particle by the removal of some or all of at least one of the non-protruding (recessing) materials. The combination of a hydrophobic protruding material or hydrophobic coated surface with the topography of the particle results in superhydrophobicity of the particles. The superhydrophobic glass material is preferably a perfluorinated or fluorinated organic material. The coating can be a fluorinated self-assembly monolayer.
[0020] There are no limits to the variations of sizes and shapes of the nanostructured surface of the particles. The blend or composite used to form the particles may be made from any materials differentially etchable by any known etching method or combination of methods.
[0021] The respective interpenetrating contiguous materials used to form the particles are differentially etchable (i.e. have different etch rates), when subjected to one or more etchants and have an interconnected structure with two or more phases, such as that resulting from spinodal decomposition. The phase separation permits the generation of a protruding phase and a recessive phase by differentially etching the particles where one material phase is removed to a much greater degree than the other phase or phases. In the limit the entire more readily etched recessive phase may be removed entirely. Porosity results from the etching of the recessive phase to the extent that channels are formed within the particle, some of which may interconnect to form a continuous void generally, but not necessarily, with a tortuous path that extends from one side of the particle to another.
[0022] Superhydrophilic and superhydrophobic diatomaceous earth-derived powder can be prepared where porous diatomaceous earth (DE) particles having a surface that is a continuous hydrophobic layer which conforms to and is bound to the surface of the DE particles. Further explanation of the DE particles is found in co-pending U.S. patent application Ser. No. 11/777,486, entitled “Superhydrophobic Diatomaceous Earth”, filed Jul. 13, 2007, herein incorporated by reference. The superhydrophilic DE particles preferably have the surface structure of uncalcined DE. The hydrophobic layer is preferably a self assembled monolayer (SAM) such that the topography of the DE particle is retained. Preferred hydrophobic layers include perfluorohydrocarbon moieties, and a preferred perfluorohydrocarbon moiety includes a tridecafluorohexyl unit. Alternately the hydrophobic layer can include hexafluoropropene oxide oligomer moieties. It may be advantageous to mill or partially crush the DE in order to have smaller grains and thus increase the powder uniformity and total coverage. But, it is anticipated that over crushing the DE particles to the point that the resulting grain sizes are less than 1 micron may reduce or even eliminate its superhydrophobic behavior. This is the potential advantage with the spinodal glass powder in that it can be crushed to a much smaller size and will still retain its superhydrophobic behavior.
[0023] Both the SHL and SHB powder can be disposed on fabric using electrostatic spraying which places a negative charge on the powder particles. One example electrostatic gun charges the powder particles to 10,000 volts. When sprayed in the vicinity of a grounded metal plate, the particles accelerate toward the plate via electrostatic forces. Non-woven fabrics were placed between the charged powder and a grounded plate. The powder hit the polymer based fabrics with a high velocity causing the powder to be embedded into the polymer matrix (i.e. fabric surface). The result is a fabric surface with embedded both superhydrophilic and superhydrophobic powder making the fabric extremely water attractive or repellant.
[0024] An alternative to embedding the particles into the fabric surface is to add the particles during production of these fabrics. During the “sticky” stage of the process, the fabric surface can easily bond to other materials, especially porous materials like the superhydrophilic and superhydrophobic powders. The powder is electrostatic sprayed onto the fabric at that stage thereby making the particles integral with the fabric surface.
[0025] The SHL and SHB fabric can also be produced by any typical solid-on-solid process for the textile industry including xerographic printing of fabrics, liquid spray coloration, liquid spray finishing of fabrics, chemical binding of nonwoven fabrics, fluoropolymer finishing of nonwoven fabrics using electrostatic spraygun systems, and slashing of yarns using a fluidized bed system. Any textile process involving applying a chemical that produces a film on fiber surfaces (“interfiber finishes”) is a candidate. The electrostatic liquid spray approach uses oligomeric resins that require no solvent and thereby results in 100% solid deposition on the textile after film cure. This approach opens the possibility for both intrafiber finishing (e.g., permanent press resins) and solid shade coloration.
[0026] Another approach to binding both superhydrophilic and superhydrophobic powders to fabric is to chemically bond the powders to the given fabric via bonding agents that allow the powders to bind to the given substrate without destroying the powder's properties. There are many potential bonding agents which can be used. One powder binding method uses a solution consisting of either the superhydrophilic or superhydrophobic powder, a type of solvent (e.g. acetone) and small amounts of binder material (e.g. polystyrene or an acrylic resin based binder known as FastTrack XSR). The solution is “painted” on a fabric surface. When the solvent dries, the powder is bonded to the surface via the bonding agent.
[0027] Chemical or resin bonding is a generic term for interlocking fibers by the application of a chemical binder. The chemical binder most frequently used to consolidate fiber is water-borne latex. Most latex binders are made from vinyl materials, such as polyvinylacetate, polyvinylchloride, styrene/butadiene resin, butadiene, and polyacrylic, or their combinations. Latexes are extensively used as nonwoven binders, because they are economical, versatile, easily applied, and effective adhesives.
[0028] The chemical composition of the monomer or backbone bonding material determines stiffness/softness properties, strength, water affinity (hydrophilic/hydrophobic balance), elasticity, durability, and aging. The type and nature of functional side groups determines solvent resistance, adhesive characteristics, and cross-linking nature. The type and quantity of surfactant used influences the polymerization process, polymer stability, and the application method.
[0029] Chemical binders are applied to fabric in amounts ranging from about 1% to as much as about 60% by weight. In some instances, when clays or other weighty additives such as the diatomaceous earth powder are included, add-on levels can approach or even exceed the weight of the fabric web. Waterborne binders are applied by spray, saturation, print, and foam methods. A general objective of each method is to apply the binder material in a manner sufficient to interlock the fibers and provide SH fabric properties. The common methods of bonding include saturation, foam, spray, print and powder bonding.
[0030] According to the present invention, it has been discovered that both superhydrophilic and superhydrophobic powder can be applied to fabrics. Indeed, it is believed that both superhydrophilic and superhydrophobic coatings may be applied according to one or more methods of the present invention to a surface of essentially any article made from essentially any material. The degree of water attractiveness and repellent is controlled in the manufacturing process of the fabric. A controlled admixture of SHL and SHB particles can control the degree of water repellent behavior in the fabric.
[0031] The SHL and SHB powder compositions when deposited on a fabric forms a composite having increased water repellency or attractiveness compared to the fabric alone. Both superhydrophilic and superhydrophobic coating compositions and methods of the present invention may be selected singularly or in combination to produce a composite having a surface that is selectively superhydrophilic or superhydrophobic (e.g., a contact angle between the coating and water thereon of less than about 5° for SHL or at least about 150°, preferably at least about 160°, more preferably at least about 165°, and still more preferably at least about 170° for SHB). In addition to increasing the hydrophobicity or hydrophilicity of a fabric, a coating of the present invention may impart the property of self-cleaning.
[0032] While there has been shown and described what are at present considered the preferred embodiments of the invention, it will be obvious to those skilled in the art that various changes and modifications can be made therein without departing from the scope.
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Superhydrophilic and superhydrophobic fabrics are taught having a superhydrophilic or superhydrophobic powder disposed on the fabric. The superhydrophilic powder has at least one material of sodium borosilicate glass and porous diatomaceous earth. The powder material has a contiguous interpenetrating structure with a plurality of spaced apart nanostructured surface features. The superhydrophilic powder is switched to superhydrophobic by adding at least one superhydrophobic material of perfluorinated organics, fluorinated organics, and self-assembled monolayers.
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FIELD OF THE INVENTION
The field of this invention is control systems for operating subsurface safety valves and more particularly control systems with a piston in pressure balance to the surrounding annulus.
BACKGROUND OF THE INVENTION
Subsurface safety valves are operated from the surface normally through control lines that run outside the production tubing. These valves are typically of the flapper type where a control system, when pressurized from the surface overcomes a closure spring on a flow tube to push the flapper 90 degrees into the open position behind the shifting flow tube. Removal of pressure from the control system allows the closure spring that had previously been held in a compressed position to then push the flow tube away from the flapper so that a torsion spring can bias it back against its seat to prevent flow from the formation from going up the production string.
These systems have to deal with issues such as failing in a safe mode if one or more seals in the control system fail. They also have to address offsetting the hydrostatic pressure in the control line. Systems with a single control line down to the subsurface safety valve typically have a pressurized chamber at the valve preset with enough pressure for the expected depth of the valve to offset the control line hydrostatic pressure so that on removal of applied control line pressure from the surface, the closure spring that acts on the flow tube doesn't have to overcome the hydrostatic pressure from the control line. A single control line system that addresses fail safe failure modes of the various seals is U.S. Pat. No. 6,109,351. Alternatively a closure spring is provided that is strong enough to overcome the control line hydrostatic pressure particularly in shallower wells. Other systems simply cancel out control line hydrostatic pressure with a balance line from the opposite side of an operating piston than the main control line. One example of such systems is U.S. Pat. No. 6,173,785. Some two line systems also incorporate pressurized chambers such as U.S. Pat. No. 6,427,778.
Some of these designs employ a passage through the piston for the purpose of obtaining a fail safe closure mode if one or more of the system seals malfunction or if a control line is sheared. The prior systems typically separated tubing pressure from control line pressure and made no reference to the surrounding annulus. Typically the operating piston in the control system had to have a mechanical connection to the flow tube to move the flow tube to open the valve. That mechanical connection was exposed to tubing pressure and the operating piston featured a pair of seals in a housing so that a portion of the operating piston in the region that it connected to the flow tube was exposed to tubing pressure but remained in pressure balance from tubing pressure.
The present invention addresses alternative approaches to the past designs that reference the surrounding annulus. Some embodiments operate differently than others during failure modes and this will be explained in detail when the various embodiments are described in detail. Those skilled in the art will appreciate the various aspects of the invention from the description of the preferred embodiment and associated drawings that appear below with the understanding that the full scope of the invention is measured by the appended claims.
SUMMARY OF THE INVENTION
A control system for a subsurface safety valve references the surrounding annulus to put the operating piston in pressure balance. Depending on the configuration and which seal in the system fails, the various embodiments can differ in their failure modes. With the lower end of the piston exposed to annulus pressure all failure modes close the flapper. With the lower end of the piston exposed to tubing pressure, failure of any of the seals except one will result in flapper closure.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic view of a single line control system with a piston pressure balanced to the annulus;
FIG. 2 is an alternative embodiment to FIG. 1 and still having a pressure balanced piston to the annulus; and
FIG. 3 is an alternative to the embodiment in FIG. 2 and having a piston in pressure balance to the annulus; and
FIG. 4 is a variation of FIG. 1 showing an annular piston rather than a rod piston with a balance control line to the surface.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 is a schematic representation of a subsurface safety valve that those skilled in the art will appreciate can illustrate the various embodiments of the present invention. Typically, a flapper 10 is mounted on a pivot 12 that can combine a torsion spring (not shown) to urge the flapper 10 against the seat 14 . The flapper 10 is pushed to turn 90 degrees and go behind an advancing flow tube 16 that is forced to move against a return bias from closure spring 18 . Passage 20 goes through a housing that is partially shown as 22 . A string from the surface represented by arrow 24 is in flow communication with passage 20 in housing 22 in a known manner. Similarly arrow 26 represents the continuation of a tubing string to the producing zone further down in the well.
A single control line 28 connects into housing 22 into chamber 30 above the operating piston 32 . Chamber 34 is on the other side of piston 32 from chamber 30 and it communicates to the surrounding annulus around housing 22 through passage 36 .
Piston 32 is preferably a rod piston with seals 40 , a lower seal, and seal 42 an upper seal. There is a through passage 44 going from lower end 46 to upper end 48 of piston 32 . Above upper end 48 is a chamber 50 in housing 22 that gets tubing pressure communicated to it through the passage 44 from inlet 52 . Link 53 connects piston 32 to flow tube 16 .
In operation, applied pressure from control line 28 raises the pressure in chamber 30 to the point that spring 18 is compressed and the flapper 10 goes open. Removal of pressure from the control line 28 allows the spring 18 to overcome the net difference between hydrostatic pressure in line 28 and the surrounding annulus pressure. The spring 18 is sized to overcome the net pressure on piston 32 between control line hydrostatic and annulus pressure apart from seal friction at seals 40 and 42 when piston 32 moves. Piston 32 is mechanically coupled to flow tube 16 below seal 40 which is exposed to tubing pressure on one side and annulus pressure on the other side. Seal 39 , the piston seal, separates chambers 30 and 34 . Seal 42 is on one side of piston seal 39 and seal 40 is on the opposite side of seal 39 from seal 40 . In most cases a net closing force acts on piston 32 from tubing pressure pushing up on seal 40 and annulus pressure pushing down on seal 42 .
If seal 40 fails, the pressure in the tubing will communicate to the surrounding annulus and pressurize chamber 34 forcing the piston 32 up and the flapper 10 will go closed. If seal 39 fails in any illustrated embodiment, there cannot be a pressure differential across the piston 32 from control line 28 and the closure spring 18 will make the flapper 10 close. However if seal 42 fails then tubing pressure will get into chamber 30 and prevent spring 18 from closing the flapper 10 since spring 18 is not sized for overcoming tubing pressure because the flow tube 16 is in pressure balance to tubing pressure. Hence in this embodiment, failure of seal 42 makes the valve stay open.
FIG. 2 is a modified design of FIG. 1 . The difference is that a second lower seal 38 is added and the lower 46 ′ end of piston 32 ′ is now exposed to annulus pressure rather than tubing pressure. Annulus pressure also goes through inlet 52 ′ to chamber 50 ′. The piston 32 ′ is in pressure balance from annulus pressure acting up on lower seal 38 and down on upper seal 42 ′ through chamber 50 ′. Piston 32 ′ is also in pressure balance from tubing pressure pushing up at seal 40 ′ and down at seal 38 because those seals straddle the link 53 ′ that connects the piston 32 ′ to the flow tube 16 ′.
If seal 40 ′ fails tubing pressure enters chamber 34 ′ and the annulus through passage 36 ′ pushing the piston 32 ′ up and the flapper 10 ′ will close. If seal 38 fails tubing pressure will leak into the annulus and get into chamber 34 ′ and again the flapper 10 ′ will close. If seal 42 ′ breaks pressure in the control line 28 ′ will pass into the annulus through chamber 50 ′ and passage 44 ′ and the closure spring 18 ′ will be able to close the flapper 10 ′. The design of FIG. 2 fails closed if any seal 38 , 40 ′ and 42 ′ fails.
FIG. 3 is virtually the same as FIG. 2 with the difference being that piston 32 ″ is solid and the passage through it has been eliminated. However, a connection 60 to the annulus has been added to chamber 50 ″ so that the top 48 ″ of the piston 32 ″ is again in communication with the annulus despite there being no passage through piston 32 ″. Inlet 52 ″ exposes the lower end 46 ″ of piston 32 ″ to annulus pressure present in chamber 62 . In all other respects, the FIG. 3 design functions and fails the same way as the FIG. 2 design.
FIG. 4 is similar to FIG. 1 except the piston has an annular shape rather than a rod shape as illustrated in FIG. 1 and is pressure balanced with a balance line that runs to the surface. The flow tube 100 has a piston 102 integrated into it with a seal 104 to separate compartments 106 and 108 . Tubing pressure is in passage 110 . Downward movement of the flow tube 100 rotates the flapper 112 and compresses the spring 114 . Compartment 106 is connected to a first control line represented schematically by arrow 116 and compartment 108 is connected to another control line running back to the surface and schematically represented by arrow 118 . Seals 120 and 122 are preferably the same size so that piston 102 is in pressure balance from the equal hydrostatic pressure in lines 116 and 118 when no pressure is being applied to either line from the surface. Seals 120 and 122 have tubing pressure in passage 110 acting on one side and control line pressure 116 acting on the other side of seal 120 and balance line pressure 118 acting on the other side of seal 122 .
In operation, the flapper 112 is opened with pressure applied in line 116 that compresses spring 114 and drives the flow tube 100 down against the flapper 112 . Removal of pressure on line 116 allows the spring 114 to drive the flow tube 100 up so that the flapper 114 closes. Since there is a balance of hydrostatic forces on piston 102 the spring 114 does not have to be sized to oppose any hydrostatic force acting on piston 102 since there is no such force acting on it in this embodiment.
If seal 104 breaks then the flapper 112 will close under the force of spring 114 . Failure of seal 122 will allow tubing pressure from passage 110 into chamber 108 forcing the flow tube 100 up and the flapper 112 will close. Failure of seal 120 will send tubing pressure from passage 110 to chamber 106 and will likely overpower spring 114 to hold the flapper 112 open unless pressure is applied to the control line 118 .
Those skilled in the art will appreciate that a variety of control systems are disclosed that use a single control line and a pressure balanced piston with respect to the annulus. The designs that fail safe closed are also pressure balanced to tubing pressure as well. Pressure balance to the annulus can occur at opposed ends with bore through the piston or with separate exposure of opposed ends of the piston to annulus pressure. In the preferred embodiment the piston can be one or more rod pistons but other piston shapes are contemplated. Pressurized chambers or offsets for control line hydrostatic pressure are not needed. The annulus pressure is used to at least in part offset the control line hydrostatic pressure and the closure spring 18 is sized to overcome net force on the piston from the net difference in pressure acting on it from the control line trying to push it down and the annulus pressure trying to push it back up.
The above description is illustrative of the preferred embodiment and many modifications may be made by those skilled in the art without departing from the invention whose scope is to be determined from the literal and equivalent scope of the claims below.
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A control system for a subsurface safety valve references the surrounding annulus to put the operating piston in pressure balance. Depending on the configuration and which seal in the system fails, the various embodiments can differ in their failure modes. With the lower end of the piston exposed to annulus pressure all failure modes close the flapper. With the lower end of the piston exposed to tubing pressure, failure of any of the seals except one will result in flapper closure.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to snap-together modular ventilation fan assemblies for electronics enclosures.
2. Description of Related Art
Modular ventilation fan assemblies, sometimes called fan tray assemblies (or more briefly, “fan trays”) are used for mounting ventilation fans to electronics enclosures, such as computer enclosures. Conductive enclosures are used to contain electromagnetic interference (EMI) generated by electronic equipment, and ventilation fans are often used for thermal control of their enclosed interior spaces. The fan tray provides for convenient mounting of one or more ventilation fans to the electronics enclosure while maintaining the EMI-shielding integrity of the enclosure. The fan tray may also provide a convenient location for mounting a control circuit for the ventilation fan or fans in the fan tray.
The ventilation fan itself is usually a modular unit that includes a rotor and a motor encased in a plastic housing. As such, it does not provide EMI shielding and may itself be a source of EMI. Fan trays therefore typically provide metal grills on opposite sides of the fan to electromagnetically isolate the ventilation fan from the environment outside of the fan tray, while allowing for the passage of air through the fan tray. At the same time, the metal grills and sheet metal walls of the fan tray maintain electromagnetic isolation for the interior of the electronics enclosure and serve as part of the wall thereof.
Fan trays are often mounted to the electronics enclosures using a pair of opposing side rails that engage corresponding rails in the electronics enclosure. The fan tray may be mounted to, and removed from, the enclosure by sliding the tray along these rails. The fan tray may be secured to the enclosure using a screw or like fastener after being slid into place along the rails. As modular assemblies, prior art fan trays facilitate assembly and repair of electronics enclosures, particularly when a fan control circuit is included in the fan tray.
However, prior art fan trays are subject to various shortcomings. They are typically assembled from sheet metal components and fastened together using screws or like fasteners. Screws are also used to fasten assembled fan trays to electronics enclosures. The use of screws or like fasteners increases assembly and removal time, and increases the number of tray components. The use of these prior art fasteners can also damage the fans and/or take the fan trays out of industry standards. For example, if too much pressure is applied at the fan edges, the fans can be damaged. By contrast, if too little pressure is applied at the fan edges, the fans in the fan trays produce a high amount of acoustical noise that can take the fan trays out of industry standards (e.g., standards on restricting the amount of noise produced). All of these factors can add substantially to the cost of fan trays, as well as create inconveniences for users.
It is therefore desirable to provide a fan tray assembly that overcomes these and other shortcomings of prior art fan tray assemblies, while retaining their advantages. More specifically, it is desirable to provide a fan tray assembly that has features in which airflow is not impeded, acoustical noise is reduced, assembly and disassembly is simplified, and cost of manufacturing is reduced.
SUMMARY OF THE INVENTION
The present invention provides a fan tray assembly that requires no removable fasteners, spring steels (e.g., not standard sheet steels), or other loose hardware in its assembly. The fan tray assembly can be used with prior art electronics enclosures while requiring minimal or no modifications to the enclosure. It can be assembled from inexpensive sheet metal pieces (shells) without the need of removable fasteners or spring steels, for decreased assembly cost. For this purpose, the shells can include attachment features for attaching the shells to one another, and retention features for retaining one or more ventilation fans between the shells. The attachment and retention features (or coupling elements) can be formed integrally with the shells from the same sheet of material (and/or having no spring steel). Taken together, the attachment and retention features reduce or eliminate the need to use loose hardware, spring steels, or adhesive for fastening during assembly.
Advantageously, the fan tray assembly may also comprise a pivoting grab handle to assist with removal of the fan tray assembly from the enclosure. The pivoting grab handle may be advantageously attached to the fan tray assembly without any fasteners. The fan tray may also provides for attachment of a fan control circuit on a printed circuit board (PCB) without the use of any fasteners.
Other beneficial features of the fan tray assembly include improved air grills and/or air holes that substantially improve air flow through the fan tray. A more complete understanding of the fan tray assembly will be afforded to those skilled in the art, as well as a realization of additional advantages and objects thereof, by a consideration of the following detailed description of the preferred embodiment. Reference will be made to the appended sheets of drawings which will first be described briefly.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of an exemplary fan tray assembly.
FIG. 2 is an exploded assembly view of the exemplary fan tray assembly shown in FIG. 1 .
FIG. 3 is an exploded assembly view of an exemplary coupling feature for an exemplary fan tray assembly.
FIG. 4 is an exploded assembly view of another exemplary coupling feature for an exemplary fan tray assembly.
FIG. 5 is another exploded assembly view of the exemplary coupling feature shown in FIG. 4 .
FIG. 6 is a perspective view of a snap element shown in FIG. 3 .
FIG. 7 is a perspective view of another snap element shown in FIG. 3 .
FIG. 8 is a perspective view of a snap element shown in FIGS. 4 and 5 .
FIG. 9 is an exploded assembly view of another exemplary fan tray assembly.
FIG. 10 is a side view of an exemplary fan tray assembly, showing operation of an exemplary handle for the exemplary fan tray assembly.
FIG. 11 is another side view showing operation of the exemplary handle for the exemplary fan tray assembly of FIG. 10 in a pull mode.
FIG. 12 a detail view of a retention dimple on the shells of the exemplary fan tray assembly shown in FIGS. 1 and 2 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention provides a fan tray assembly that overcomes the limitations of prior art fan trays. In the detailed description that follows, like element numerals are used to indicate like elements that appear in one or more of the drawings.
Referring to FIGS. 1 and 2 , exemplary fan tray 100 comprises two opposing shells 116 , 118 , sometimes called brackets. The shells 116 , 118 are attached to one another using a plurality of interlocking attachment features, such as top center snap element 170 and tab slot 174 and corresponding bottom center snap element 140 and snap tab 182 , shown in FIG. 3 or bottom corner snap element 145 and hook 185 and corresponding top hook eyelet 175 shown in FIGS. 4 and 5 . Each shell is made of a suitable sheet material, such as sheet steel or other conductive and structural material, which may be suitably surface treated or coated as known in the art. All of the features of the shells may be formed in the same sheet of material, such as by a suitable stamping and bending operation, thereby eliminating unnecessary assembly operations. In one embodiment, the shells are formed using only standard sheet material (e.g., using only standard sheet steels without spring steels).
Each of shells 116 , 118 has a plurality of grills and/or openings 117 , 138 forming an inlet and an outlet for passage of air through the shells, of which two grills 117 in the top shell 118 are shown in FIGS. 1 and 2 and a plurality of octagonal openings 138 in the bottom shell 116 are shown in FIG. 2 . In one embodiment of the present invention, the plurality of octagonal openings 138 do not have to be substantially aligned with the grills 117 in the opposing shell, for efficient air flow through the fan tray.
Ventilation fans 112 are retained between the two shells by retention features, such as dimples 188 shown in FIGS. 2 , 5 , and 12 . The retention features are described in more detail below. Each of the ventilation fans 112 , as known in the art, can comprise a rotor (not shown) encased in a frame 124 . Frame 124 may include one or more features for engagement with retention features (such as dimples 188 ) of the shells. For example, the fan frame 124 may include a plurality of through holes 126 . Such holes are commonly used in prior art assemblies for holding threaded fasteners used for attaching the fan to an assembly. Utilization of these holes in a new and different way in the present assembly advantageously allows the fan tray assembly to make use of commonly available prior art ventilation fans. Each of the ventilation fans 112 also include a cable connector (not shown) for connecting the fan to a power source.
Assembly 100 additionally includes an electrical connector 122 for transmitting power to the ventilation fan. Connector 122 may also be used to transmit signals and power to a control circuit in the fan tray assembly. It may be connected to the ventilation fan using cable connector (not shown) and circuits in a printed circuit board (PCB) 120 , or in some other fashion. Connector 122 is retained by the shells 118 , 116 and oriented towards an exterior of the fan tray assembly, as shown in FIG. 2 . Connector 122 can be retained by mounting to the PCB 120 that is, in turn, retained by the shells 118 , 116 , via bottom corner snap element 145 , slot 156 , and partial slots 153 on the shell 116 , as shown. In the alternative, PCB 120 may be replaced by a passive structural plate (for example, if no control circuit is needed in the fan tray assembly), or mounted to the fan tray assembly separate from a PCB or plate. The embodiment shown in FIG. 2 has the advantage of retaining the connector and a control circuit using the same mounting system, which is described in more detail below.
Interlocking attachment and retention features (or couplings or coupling elements) are preferably provided in areas near opposite sides 40 a and 40 b of the shell 116 , as shown in FIGS. 1 to 8 . The interlocking attachment and retention features of the shell 116 are configured to engage complementary interlocking attachment and retention features of the shell 118 . The interlocking attachment and retention features of the shell 118 include a top center snap element 170 incorporated with a snap slot 174 , a hook eyelet 175 near a first end 150 of shell 118 , and an attaching tab 68 on a second end 148 of shell 118 . The interlocking attachment and retention features of 116 include bottom center snap element 140 incorporated with a snap tab 182 and bottom corner snap element 145 incorporated with a hook 185 .
FIGS. 3 and 6 illustrate an embodiment of the top center snap element 170 in more detail. The top center snap element 170 is coupled to the shell 118 on a bottom face 146 of the shell 118 . The top center snap element 170 extends outward from the bottom side of 146 . The top center snap element 170 can be contiguous with shell 118 and made from the same material as the shell 118 . The top center snap element 170 includes a snap tab slot 174 formed in the top center snap element 170 . The snap tab slot 174 is attachable with the corresponding bottom center snap tab 182 of the bottom shell 116 . The top center snap element 170 also includes a transition section 176 at an end distal from the shell 118 . The transition section 176 can be an angled region of the top center snap element 170 that allows for the top center snap element 170 and corresponding bottom center snap element 140 to be coupled such that binding or interference of the two elements 170 , 140 is minimized. Opposite the transition section 176 is a base section 178 of the shell 118 . The base section 178 is located on the bottom face 146 of the shell 118 . The base section 178 allows for flexure or biasing of the top center snap element 170 , such that the top center snap element 170 can deflect aside and then return to a non-biased position when attaching with the corresponding bottom center snap element 140 when assembling the fan tray assembly 100 . In one embodiment of the present invention, the deflection and then return to the non-biased position of the top center snap element 170 is accomplished using only standard sheet steel having no spring steel. In another embodiment, the top center snap element 170 is designed using statistical tolerance analysis to ensure a good quality fit with the bottom center snap element 140 .
Referring now to FIGS. 3 and 7 , an exemplary bottom center snap element 140 is shown. The bottom center snap element 140 is coupled to a top face 180 of the shell 116 such that the bottom center snap element 140 extends outward from the top face 180 . The bottom center snap element 140 can also be contiguous with the shell 116 and made from the same material as the shell 116 . The bottom center snap element 140 includes a snap (or lock) tab 182 formed in the bottom center snap element 140 . The snap tab 182 is attachable (or lockable) with a corresponding top center snap element 170 (e.g., the tab slot 174 of the top center snap element shown in FIG. 6 ). The bottom center snap element 140 also includes a transition section 184 at an end distal from the shell 116 . The transition section 184 can be an angled region of the bottom center snap element 140 that allows for the bottom center snap element 140 and corresponding top center snap element 170 to be coupled such that binding or interference of the two elements 170 , 140 is minimized. Opposite the transition section 184 is a base section 186 of the shell 116 . The base section 186 has a flexure region 198 and a wire mount region 190 . The base section 186 is located on the top face 180 of the shell 116 . The flexure region 198 of the base section 186 allows for flexure or biasing of the bottom center snap element 140 , such that the bottom center snap element 140 can deflect aside and then return to a non-biased position when attaching with the corresponding top center snap element 170 when assembling the fan tray assembly 100 . In one embodiment of the present invention, the deflection and then return to the non-biased position of the flexure region 198 of the bottom center snap element 140 is accomplished using only standard sheet steel having no spring steel. In another embodiment, the bottom center snap element 140 is designed using statistical tolerance analysis to ensure a good quality fit with the bottom center snap element 170 .
Referring still to FIG. 7 , mounting dimples (or numbs) 188 are also shown to be disposed on the base section 186 or on a face of the wire mount region 190 . The mounting dimples 188 are designed for securing the ventilation fans 112 without the use of separate fasteners. That is the mounting dimples 188 can fit into the through holes 126 of the ventilation fans 112 for coupling the fans 112 to the shell 116 . A separate wire mount 195 is also shown to be located on the shell 116 and is used to secure the wiring(s) for the ventilation fans 112 and/or other devices of the fan tray assembly 100 . Similarly, the wire mount region 190 of the base section 186 can also be used to secure the wiring(s) for the ventilation fans 112 . Other wire mounts, such as wire mount 195 shown in FIG. 8 , can also be located on the shell 116 to secure the wiring(s) of the ventilation fans 112 and/or other devices associated with the fan tray assembly 100 .
Referring to FIGS. 4-5 and 8 , an exemplary embodiment of the bottom corner snap element 145 and the top corner snap element 165 are shown. The bottom corner snap element 145 is coupled to the shell 116 on a top face 180 of the shell 116 such that the bottom corner snap element 145 extends outward from the top face 180 . The top corner snap element 165 is defined at around a corner of a first end 148 of shell 118 . The bottom corner snap element 145 includes a hook 185 , a stop block 186 , and a bottom corner block 189 . The top corner snap element 165 includes a hook eyelet 175 located on shell 118 and a top block 176 (or blocks 176 and 179 ) located on a bottom face 147 of shell 118 : The bottom face 147 is slightly lower than a second and larger bottom face 146 of shell 118 (e.g., the bottom face 146 shown in FIGS. 2 and 6 ). The top block 176 , 179 is partially defined by a vertical plane 148 that joins the first bottom face 147 with the second bottom face 146 . The hook 185 of the bottom corner snap element 145 and bottom corner and stop blocks 186 and 189 of the bottom corner snap element 145 are all formed in the corner snap element 145 . The hook 185 is attachable (or lockable) to the corresponding top hook eyelet 175 . The bottom corner block 189 and the stop block 186 can be use to block corresponding top block 176 (or top corner block 179 and face block 176 , respectively). Thus, the corner snap elements 145 and 165 uses the hook 185 and the hook eyelet 175 , the face and stop blocks 176 and 186 , and the top and bottom corner blocks 179 , 189 to securely snap, attach, or lock the bottom corner snap element 145 with the top corner snap element 165 .
Referring still to FIG. 8 , the bottom corner snap element 145 also includes a base section 86 . The base section 86 is proximate to the shell 116 on the top face 180 . The base section 86 allows for flexure or biasing of the bottom corner snap element 145 so that the bottom corner snap element 145 can deflect aside and then return to a non-biased position when attaching with the top corner snap element 165 . In one embodiment of the present invention, the deflection and then return to the non-biased position of the bottom corner snap element 145 is accomplished using only standard sheet steel having no spring steel. In another embodiment, the corner snap elements 175 and 165 are designed using statistical tolerance analysis to ensure a good quality fit with each other. A wire mount 195 is also shown to be located on the top face 180 . The wire mount 195 secures wiring(s) for the fans 112 and/or other devices associated with the fan tray assembly 100 . For example, a bottom face of the wire mount 195 can be used with the top face 180 to sandwich (or secure) the wiring(s) in place.
The fan tray assembly of the present invention can further include a handle 300 . Referring now to FIG. 9 , fan tray 200 comprises outlet grill shell 202 , inlet shell 204 , handle 300 , and, interposed between shells 202 and 204 , ventilation fans 208 a , 208 b and circuit board 206 . Ventilation fans 208 a , 208 b are connected by cables (not shown) to circuit board 206 . Circuit board 206 is mounted at an end of fan tray 200 opposite to handle 300 . The circuit board 206 includes an interface connector 212 that extends away from the end of the fan tray. The interface connector 212 is for engaging with a corresponding connector in an electronics enclosure (not shown).
Snap tabs 304 a , 304 b fit between flanges 216 a , 216 b of fan 208 a , and each tabs 304 a , 304 b is inserted into one of the mounting holes 210 . To assemble handle 300 between flanges 216 a , 216 b , the snap tabs 304 a , 304 b are compressed towards one another until the tabs 304 a , 304 b snap into place inside of holes 210 . Thus, assembly of handle 300 to the fan tray may be accomplished without using any separate fastener such as a screw or rivet. In the alternative, handle 300 may be attached to components of fan tray 200 other than fan 208 a . Yet another alternative is to provide holes as retention features in tabs 304 a , 304 b , which snap over dimples on a fan or other component of a fan tray.
The handle of the fan tray assembly of the present invention can be used to assist a user to disengage the connector of the fan tray assembly from an electronic enclosure. Referring to FIGS. 10 and 11 , a handle 400 of an exemplary fan tray assembly of the present invention is shown. Referring to FIG. 10 , application of force 410 causes the bump edge 408 to exert an amplified force 412 on the electronic enclosure, generally in the direction of the force arrow 412 . The pivot point is in turn determined by the location of the bushings in the tabs of the handle (e.g., as previously described referencing FIG. 9 ). In reaction to force 412 , a disengagement force 414 is exerted on fan tray 402 at the pivot point of the handle, generally in the direction of arrow 414 . With reference still to FIG. 10 , a horizontal force acting on the fan tray towards the right will tend to disengage the connector 404 . After connector 404 has disengaged from the electronic enclosure as shown in FIG. 11 , handle 400 may be used as a pull handle. The user then applies a pulling force on the lever arm of the handle. An exemplary pulling force is indicated by the arrow 414 of FIG. 11 . Removal of fan tray 400 will proceed in the direction of the arrow 414 .
It should be apparent that fan tray assembly of the present invention reduces or eliminates any need to use separate fasteners, spring steels, or adhesives in its assembly. As used herein, a “separate fastener” is any piece of loose fastening hardware, such as a screw, bolt, rivet, clip, tie, and so forth. “Spring steels” include a spring steel sheet (e.g., not a standard structural steel sheet or not a standard sheet steel) and/or a steel sheet laminated with a spring steel sheet. “Adhesive” is used broadly to include solder, braze, and welded material, as well as resin-based adhesive material. For example, shells 116 , 118 may be attached by the above described attachment features without the use of separate fasteners, spring steels, or adhesives. Likewise, the ventilation fans 112 may be retained between the shells without the use of separate fasteners or adhesives.
As used herein, the terms “top” and “bottom” when applied to the shells are used merely for convenience to indicate the relative positions of the shells as shown in FIGS. 1-5 and 7 - 8 . It should be apparent that these terms do not in any way limit the orientation of the fan tray; for example, the fan tray may be oriented so that the “top” shell is underneath the “bottom” shell, and vice-versa. It should further be apparent that the features described herein as being on one of the shells may instead be provided on the other shell, so long as the complementary nature of the shells is preserved. For example, the snap tabs 182 on the bottom shell 116 may be provided on the bottom shell 118 , so long as complementary slots 174 are provided for them on the bottom shell. Many such variations are possible within the general parameters of complementary interlocking shells in a fan tray assembly according to the invention.
A suitable shape for grills 117 and/or openings 138 are shown in plan view in FIGS. 1 and 2 . Retention features (dimples) 188 are shown in FIG. 2 arranged around a periphery of shell 116 . The dimples 188 can protrudes out of shells 116 and/or 118 , and are positioned to correspond with mounting holes in a ventilation fan frame. A detail side view of an exemplary dimple 188 is shown in FIG. 12 . In an embodiment of the invention, dimple 188 is a substantially hemispherical protrusion having a radius sufficiently small to engage the holes of the fan frame. A hemispherical shape has the advantage of being readily formed without overstressing the sheet material.
Other shapes may be used for the fan retention features. For example, a pyramidal protrusion may be pressed into the sheet material for engaging a round or square hole in a fan frame. Or, the sheet material may be cut and shaped to provide a tab configured to fit in a hole or slot in a fan frame, or around exterior parts of a fan frame. In the alternative, a hole or recess could be formed in a surface of shells 116 , 118 for receiving a protruding feature of a fan frame. Whatever the configuration of the fan retention features, shells 116 , 118 should be configured to compress the ventilation fan between their interior surfaces to prevent shifting or rattling of the fan during handling or operation. In an embodiment of the invention, this compression may be supplied mainly by snap elements 140 , 170 , 145 , 165 , as shown.
When attached by the attachment features (e.g., snap tabs 182 and slots 174 ) the interior distance between the opposing shells should be such that the snap elements 140 , 170 , 145 , 165 and/or shells 116 , 118 compress the ventilation fan enough to hold it firmly in position. At the same time, the outward pressure exerted by the ventilation fan on the interlocked shells may help keep the shells locked firmly in position.
This balancing of inward compression on the fan and outward pressure on the shells stabilizes the assembly. Too much compression will impede assembly of the fan tray and may damage components. Too little compression will result in an unstable, rattling fan tray. One of skilled in the art may select a suitable sheet material and geometry to achieve a proper amount of compression for a given application. Snap elements 140 , 170 , 145 , 165 advantageously provide additional resiliency to the assembled shells with respect to the fan, thereby easing the degree of precision to which the shells need be made.
Referring now back to FIG. 2 , an exemplary controller PCB 120 for use with fan tray 100 is shown. PCB 120 defines an x-y plane on which connector 122 is located. The x-y plane is also shown in plan view in FIG. 9 . Connector 122 is for connecting the PCB to a parent assembly, and extends perpendicularly from the board 120 along a z-axis. Board 120 may be of a uniform thickness that is sufficiently less than the width of the mounting slots 156 , 153 to permit sliding of the board relative to the slots.
PCB 120 may contain a control circuit and/or electrical traces connecting connector 122 . In an alternative embodiment, PCB 120 may be replaced by a purely mechanical board or plate, for example, for connecting a ventilation fan directly to an external control circuit. It should be apparent that, in either case, a connector mounted on the board or plate may be retained in the fan tray by the shells 116 , 118 without using a separate fastener or adhesive.
Having thus described a preferred embodiment of a fan tray for an electronic enclosure, it should be apparent to those skilled in the art that certain advantages of the within system have been achieved. It should also be appreciated that various modifications, adaptations, and alternative embodiments thereof may be made within the scope and spirit of the present invention. For example, a fan tray for two individual ventilation fans has been illustrated, but it should be apparent that the inventive concepts described above would be equally applicable to fan trays for a single fan or more than two fans. For further example, particular shapes of shells, tabs, dimples, slots, latches, grills, holes, and so forth, have been illustrated, but one of ordinary skill may devise other suitable shapes for such elements in conformance with the inventive concepts herein. The invention is further defined by the following claims.
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A fan tray assembly for an electronics enclosure includes two opposing, spaced apart shells made of a sheet material. The opposing shells are attached to each other by attachment features formed in the sheet material of each shell. Advantageously, the attachment features reduce or eliminate the need for separate fasteners, spring steels, or adhesives to attach the shells. Each shell has openings and grills. Each shell also has retention features formed in the sheet material around a periphery of their respective grills. A ventilation fan unit (e.g., two fans) is retained between the two shells by the retention features. An electrical connector is connected to the ventilation fan and retained by at least one of the shells. The shells may also include features for retaining the electrical connector without using fasteners or adhesives. Such features may allow the connector to float in a plane perpendicular to its principal axis of alignment. The assembly may additionally include a handle for detaching the assembly to the electronic enclosure.
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BACKGROUND OF THE INVENTION
This invention relates to granulated solid fuel burners, and more particularly to one which insures more complete combustion of the fuel and prevents flashback in the fuel supplied thereto, which allows efficient burner operation over a wide turndown range, and which provides for control of flue gas temperature exiting the burner.
With the advent of concern for energy conservation, it has become increasingly important to provide combustion devices capable of burning less expensive and more plentiful fuels. One general type of such fuels includes the so-called granulated solid fuels such as ground wood particles, wood shavings and sawdust, and other non-wood granulated substances such as ground rubber, ground bagasse, etc. Such fuels can be difficult to burn but nevertheless can produce hot flue gases which can be used for a variety of applications, including boilers, warm air furnaces, etc. As in all combustion devices, it is important that the combustion process be carried out efficiently for, if not, the burner will generate excessive smoke and soot, and unburned or incompletely burned fuel will remain in the burner further reducing its efficiency or even interrupting its operation.
Furthermore, it is desirable that the burner have a wide turndown range, i.e., that it be capable of operating at a greatly reduced output level during periods of reduced demand or non-demand, and that it resume normal operation quickly when output demand resumes. In addition, burners of the type should be capable of easy startup.
Still further, it is desirable that the temperature of flue gases exiting the burner be controllable.
SUMMARY OF THE INVENTION
The present invention overcomes the deficiencies and satisfies the needs discussed above by providing a burner for use in burning granulated solid fuels which includes a fuel delivery and combustion air delivery assembly constructed to prevent flashback and explosions in the fuel feed system. The burner of this invention incinerates most of fuel particles quickly and allows free passage of flue gas therethrough but includes means serving to retain larger fuel particles therein until they are incinerated. The burner of this invention also includes a constant pilot assembly which utilizes a portion of the fuel entering the burner to produce a constant ignition source so that the burner can operate efficiently over a wide turndown range.
Additional objects of the present invention are to provide a burner for use in burning granulated solid fuels which is relatively inexpensive in construction, yet is reliable and efficient in performance.
Other objects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims.
To achieve the objects and in accordance with the purpose of the invention, as embodied and broadly described herein, the burner of this invention comprises a head having a lateral inlet opening at one end and an outlet opening at its other end, a combustion chamber communicating the inlet and outlet openings, means defining a passageway communicating with the inlet opening, means for delivering granulated solid fuel to the passageway, means for delivering combustion air to the passageway to mix with the fuel prior to entering the combustion chamber, the passageway and the fuel and air delivery means being constructed to provide a negative pressure in the fuel delivery means and to cause the mixture of fuel and air passing through the passageway to travel at a velocity greater than the flame speed of the fuel.
Broadly, the combustion air delivery means includes means defining a cavity surrounding the head and communicated at one end with the passageway, and means in the cavity forming a spiral duct, whereby combustion air entering the cavity is caused to travel in a spiral path around the head and to be preheated prior to entry into the passageway. In a preferred form, valve means is provided to control the flow of combustion air to the passageway.
In a preferred form, the passageway includes a tubular conduit extending into the head at the inlet opening, the fuel delivery means includes a conduit communicated with the passageway conduit, and the combustion air delivery means delivers combustion air to the passageway conduit upstream of the fuel delivery conduit. In a most preferred form, the combustion air delivery means includes a conduit which is concentric with and surrounds the passageway conduit and the fuel delivery conduit, and the latter terminates inside the passageway conduit.
In another aspect, the burner of this invention comprises a head having an inlet opening at one end and an outlet opening at its other end, a combustion chamber communicating the inlet and outlet openings, means for delivering granulated solid fuel to the inlet opening, means for delivering primary combustion air to the inlet opening, and means in the combustion chamber forming an apertured barrier for preventing passage of fuel particles larger than a predetermined size. In a preferred form, the burner includes means for delivering secondary combustion air to the combustion chamber on the upstream side of the apertured barrier. In a most preferrred form, the secondary combustion air delivery means is at the bottom of the combustion chamber.
In still another aspect, the burner of the present invention comprises a head having an inlet opening at one end and an outlet opening at its other end, a combustion chamber in the head communicating the inlet and outlet openings, means for delivering granulated solid fuel to the inlet opening, means for delivering combustion air to the inlet opening, and means for delivering cooling air to the combustion chamber at a location near the outlet opening for controlling the temperature of flue gas exiting the outlet opening.
In yet another aspect, the burner of the present invention comprises a head having an inlet opening at one end and an outlet opening at its other end, means for delivering granulated solid fuel to the inlet opening, means for delivering primary combustion air to the inlet opening, a pilot assembly in the combustion chamber including means defining a pilot chamber in the combustion chamber for receiving some of the fuel entering the inlet opening, and means for supplying air to the pilot chamber.
In a preferred form, the inlet opening is disposed laterally of the combustion chamber and the pilot assembly includes a body in the combustion chamber and having a port aligned with the inlet opening, the pilot chamber being formed in the body and communicated with the port. Desirably, the means for supplying air to the pilot chamber is also operable to supply a combustible fuel to the combustion chamber for a startup of the burner. If desired, the pilot assembly is removably attached to the head at the one end of the head to allow access to the combustion chamber.
The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with description serve to explain the principles of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a vertical cross sectional view of a preferred form of burner constructed according the the present invention;
FIG. 2 is a sectional view of the structure of FIG. 1, taken along the line 2--2 thereof;
FIG. 3 is a sectional view of the structure of FIG. 1, taken along the line 3--3 thereof;
FIG. 4 is a sectional view of the structure of FIG. 1, taken along the line 4--4 thereof; and
FIG. 5 is a partial view similar to FIG. 1 and showing a modified form of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Reference will now be made in detail to the present preferred embodiment of the invention, examples of which are illustrated in the accompanying drawings.
The preferred embodiment of the burner of this invention is shown in FIG. 1 and is represented generally by the numeral 11. This burner comprises a head having an inlet opening at one end and an outlet opening at the other end, and a combustion chamber communicating the inlet and outlet openings. As embodied herein, the burner 11 comprises a head 13 constructed of a high temperature refractory material 15 surrounded by a metal casing 17 constructed of, for example, stainless steel or aluminized steel. The head 13 is provided with an inlet opening 16 at one end and an outlet opening 18 at its other end. A combustion chamber 19 communicates the inlet and outlet openings 16,18. Preferably, the head 13 and combustion chamber 19 are cylindrical in configuration.
In accordance, with the invention, means is provided for delivering granulated solid fuel to the inlet opening, and means is provided for delivering combustion air to the inlet opening. In a preferred form, the granulated, solid fuel and combustion air are delivered to a passageway which communicates with the inlet opening, and the fuel and combustion air mix prior to entering the combustion chamber.
As embodied herein, granulated solid fuel is delivered to the burner 11 from a suitable source (not shown) through a fuel conduit 21. Preferably, delivery of the fuel is effected in a constant, controlled and metered fashion and may be carried out either by gravity or by a pneumatic transport means as will be understood by those skilled in the art.
The fuels which are useful in this invention include any fuel which can be ground or otherwise formed into granulated or particle form. Preferably, the particles should be less than about one quarter inch in diameter although other forms, such as wood shavings, can also be used. Possible fuels include granulated or ground-up wood and wood shavings, sawdust, ground rubber, sugar cane waste (bagasse) cotton gin waste, etc.
As further embodied herein, a passageway is formed by a conduit 23 which extends through the inlet opening 16 and into the combustion chamber 19. Fuel conduit 21 extends into and terminates within the passageway conduit 23 so that fuel particles conveyed through the conduit 21 pass into the passageway conduit 23 and enter the combustion chamber 19. Preferably, the passageway conduit 23 is offset from the center of the combustion chamber 19 so that entering air/fuel mixture swirls around the combustion chamber 19 (See FIG. 2).
In accordance with invention, means is provided for delivering combustion air to the burner inlet opening. In a preferred form, the combustion air delivery means includes means defining a cavity surrounding the burner head and communicated at one end with the passageway at the inlet opening. In a most preferred form, means in the cavity forms a spiral duct so that combustion air entering the cavity is caused to travel in a spiral path around the head and to be preheated prior to entry into the passageway.
As embodied herein, primary combustion air is delivered by, for example, a forced air fan (not shown) to an air inlet pipe 25 which is connected to a cylindrical shell 27 which surrounds the casing 17. The shell 27 is spaced from the casing 17 and forms an annular cavity 29 therewith. A spiral fin or vane 31 is disposed in the cavity 29 and is connected to both the shell 27 and the casing 17 so that air entering the cavity 29 through the pipe 25 is caused to travel through a spiral duct formed by the parts and in a left-hand direction as seen in FIG. 1. A suitable insulating material 34 surrounds the shell 27.
The air flowing through the spiral duct in the cavity 29 travels along a substantial length of the burner head 13 and is heated by the heat of combustion in the combustion chamber 19. The heated air exits the cavity 29 through an opening 32 and enters a closed conduit 33 which is concentric with and surrounds the conduits 21,23 (see FIG. 2). The heated combustion air then enters the passageway conduit 23 through an annular gap 35 between the conduit 23 and the conduit 21. The preheated combustion air, therefore, mixes with the fuel in the conduit 23 and the air/fuel mixture enters the combustion chamber 19.
In accordance with the invention, the passageway and the fuel and air delivery means are constructed so that a negative pressure zone is created in the fuel conduit. Also, the volume of air entering with the fuel creates a velocity in the passageway conduit such that the velocity of the entering air/fuel mixture is greater than the flame speed of the fuel. The "flame speed" of a fuel will be understood to mean the speed at which flame travels along that fuel. It will be appreciated that it is important that the velocity of fuel entering the burner 19 be greater than its flame speed to prevent flashback and/or explosion in the fuel pipeline.
As embodied herein, the annular gap 35 is sized so that combustion air passing through the gap 35 and past the end of the fuel conduit 21 causes an aspirating effect which creates a negative pressure zone in the conduit 21. Also, the diameter of the passageway conduit 23 is selected (as are other parameters of the fuel and air supply) so that the fuel and air travels through the conduit 23 at a velocity exceeding the flame speed of the particular fuel used.
The flame speed for wood particles ranges from about 8 to about 14 feet per second. The velocity of the combustion air and fuel passing through the passageway conduit 23 desirably is somewhat greater than this and desirably may be as high as about 60 feet per second.
A control valve 36 is provided at the air inlet pipe 25 to control the flow of combustion air to the burner. The valve 36 may be manually or automatically controlled as will be understood by those skilled in the art.
In accordance with the invention, means is provided in the combustion chamber forming an apertured barrier for preventing passage of fuel particles larger than a predetermined size. As embodied herein, an apertured plate 37 is provided in the combustion chamber 19 at approximately a midpoint along its length. The plate 37 is provided with a plurality of apertures or openings 39 which are sized to allow flue gases and fuel particles below a predetermined size to pass freely therethrough. Larger fuel particles, particularly those which have not been incinerated completely, impact on the plate 37 and accumulate at the bottom of the combustion chamber 19 at the upstream size of the plate 37. A secondary air inlet port 41 is provided in the head 13 near the bottom of the combustion chamber 19 and on the upstream size of the plate 37 and allows a small amount of combustion air from the cavity 29 to enter the combustion chamber at this point (see FIGS. 1 and 3). This assures the presence of combustion air to fully incinerate the larger particles in this zone. In addition, the port 41 extends tangentially to the combustion chamber to prevent the accumulation of ash in this zone.
In accordance with the invention, means is provided for delivering cooling air to the combustion chamber at a location near the outlet opening for controlling the temperature of flue gas exiting the burner. As embodied herein, cooling air is delivered by means, for example, a forced air fan (not shown) to an inlet pipe 43 which is connected to the shell 27 (see FIG. 1). An end wall 44 of the shell 27 and an annular member 46 in the shell form a cavity 48 which surrounds the head 13 and is communicated with the pipe 43 and is separated from the cavity 29. A plurality of ports 45 extend through the burner head 13 and communicate the cavity 48 with the combustion chamber 19 near the outlet opening 18. The ports 45 are equally spaced around the burner head 13 and are inclined toward the opening 18 as shown in FIG. 1.
The quantity of cooling air delivered to the combustion chamber 19 is controlled by a valve 47 in the pipe 43 which may be manually but preferably is automatically controlled. The quantity of air delivered to the pipe 43 is selected based upon the desired output temperature of the burner. Thus, it may be desirable to cool the temperature of the flue gases before they exit the outlet opening 17 for certain applications. By carefully regulating the air to the pipe 43, the output temperature of the flue gases from the burner can be closely controlled.
In accordance with the invention, a pilot assembly is provided in the combustion chamber which includes means defining a pilot chamber in the combustion chamber for receiving some of the fuel entering the burner inlet opening and means for supplying air to the pilot chamber. As embodied herein and shown in FIG. 1, a pilot block 51 is supported in an end block 53 which is fixed to the burner head 13 by a flange and bolt connection 54. The pilot block 51 and end block 53 are both constructed of high temperature refractory material and the pilot block 51 has a portion extending inwardly beyond the end block 53, as shown in FIG. 1. An outwardly diverging pilot chamber 55 is formed in the inner end of the pilot block 51 and is communicated with a passageway 57 which extends to the outer end of the pilot block 51. A port 59 extends laterally through the pilot block 51 at the pilot cavity 55.
A portion of the fuel entering the combustion chamber 19 by way of the passageway conduit 23 passes through the port 59 and enters the pilot chamber 55. During combustion in the combustion chamber 19, the fuel in the pilot cavity 55 mixes with air entering the pilot chamber 55 through the passageway 57 and burns within the pilot chamber. This produces a constant ignition source which allows the burner to operate over a wide turndown range. "Turndown" is achieved by reducing the fuel and combustion air supply to the burner.
Experiments have shown that with the constant pilot of the present invention, the burner can operate through a turndown ratio on the order of from about five to one to about six to one. Thus, if operation of the burner at full supply produces an output of 400,000 btu, the burner of this invention can be "turned down" to a level where the output is from about 66,000 to about 80,000 btu. The normal turndown ratio available on existing solid granulated fuel burners is less than about three to one and is more on the order of about two to one. Thus, the burner of the present invention may be turned down to a very low level during periods of reduced demand or non-demand without being turned off and will conserve fuel while maintaining a constant ignition source to provide instantaneous operation when demand is resumed.
As further embodied herein, the constant pilot may also serve as an ignition source for the burner during startup. Thus, a flame produced from a combustible fuel such as a mixture of air and oil may be delivered through the passageway 57 into the constant pilot chamber 55. Air and solid fuel particles in the pilot chamber 55 are ignited by this flame and serves to ignite the air/fuel mixture in the combustion chamber 19. Once ignition and combustion has been obtained, the flame source to the pilot chamber 55 is removed and only air enters the pilot chamber thereafter.
FIG. 5 shows a slightly modified version of burner constructed in accordance with the invention. In this embodiment, the end block 153 and the pilot block 151 are connected by a hinge 157 to the burner head 113. This allows the end block 153 and the pilot block 151 to be swung outwardly to a position as shown in dot-dash lines in FIG. 5 to allow free access to the combustion chamber 119. In this embodiment, a fire can be built in the combustion chamber 119 with scrap materials for burner startup. In all other respects, the embodiment of FIG. 5 is the same as shown in FIGS. 1-4 and described above and like numerals indicate similar parts in all the figures.
It will be understood that the temperature achieved in the burner of this invention is largely a function of the fuel used, and that the output temperature at the outlet opening 17 is determined by the desired use for the burner. Using ground or granulated wood particles sized 1/4" or smaller and a constant supply of primary combustion air is maintained at from about 160 to about 200 percent of theoretical, the temperature in the combustion chamber 19 can reach about 2400° to about 2500° F. which desirably is about 200° to about 300° F. below the ash fusion temperature of the fuel. Combustion air traveling through the cavity 29 is superheated and reaches a temperature of from about 800° to about 1200° F. when it passes through the annular gap 35.
Depending upon the desired use to which the burner is to be put, it may be desirable to allow the flue gases to exit the burner through oulet opening 18 at the combustion temperature, i.e., 2400° to 2500° F. Alternatively, it may be desirable that the temperature of the flue gas exiting the burner through the outlet opening 18 be somewhat less, than as low as 400° to about 500° F. In that case, sufficient cooling air is admitted to pipe 43 and enters the combustion chambers through the ports 45 to cool the flue gases to the desired temperatures.
It will be apparent to those skilled in the art that various additions, substitutions, modifications and omissions can be made to the burner of this invention without departing from the scope or spirit of the invention. Thus, it is intended that the present invention cover the additions, substitutions, modifications and omissions provided they come within the scope of the appended claims and their equivalents.
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A burner for use in burning granulated solid fuel including a burner head having a combustion chamber and inlet and outlet openings at opposite ends thereof communicated with the combustion chamber. Means is provided to deliver granulated solid fuel to the inlet opening and means is provided for delivering primary combustion air to the inlet opening. The primary combustion air is preheated by passing along the burner head prior to entry to the inlet opening and a pilot assembly in the combustion chamber maintains a constant pilot during turndown of the burner. A retention barrier in the combustion chamber retains fuel particles larger than a predetermined size in the combustion chamber to insure complete incineration thereof.
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CROSS-REFERENCE TO RELATED APPLICATIONS
The present application claims the benefit of priority to International Patent Application No. PCT/CN2008/001479 filed 15 Aug. 2008, which further claims the benefit of priority to China Patent Application No. 200710120319.8 filed 15 Aug. 2007, the contents of which are incorporated herein by reference in their entirety.
FIELD OF THE INVENTION
The present invention relates to wireless communication technologies in the field of communications, and particularly to a method for allocating a tracking area list of a User Equipment, a Mobility Management Entity and a User Equipment.
BACKGROUND OF THE INVENTION
In a mobile communication system, the mobility management of a User Equipment (UE) is a fundamental and necessary logical function of the mobile communication network.
For the purpose of addressing and identifying the UE in the mobility management, a Core Network (CN) divides a network into a series of areas in terms of logical architecture, and allocates a separate identity for each of the areas. Depending on the division criteria, the network is divided into different areas, including, for example, a Tracking Area (TA) and a Routing Area (RA) provided with a Tracking Area Identity (TA ID) and a Routing Area Identity (RA ID) respectively.
For the sake of simplification, the reference to an area below is made by taking the Tracking Area as an example.
The Core Network allocates a specific area (which is indicated by at least one TA ID) for a DE attached to the network, and when the DE moves from the current allocated area to an unallocated area, the UE initiates the TA Update procedure to the network.
A Mobility Management Entity (MME) in the Core Network is responsible for the mobility management of the UE, and the MME includes, but not limited to a Mobile Switching Center (MSC), a Serving GPRS Support Node (SGSN), and a signaling terminating node at a non-access layer of a core network of the Evolved Packet System (EPS) of the Third Generation Partnership Project (3GPP).
The Core Network includes a plurality of MMEs, each of which manages a certain range of areas, that is, each MME manages a limited range of areas. It is possible for a UE to move out of an area allocated by the current MME to the UE, and further move out of the entire areas managed by the current MME.
In the traditional 3G mobile communication system, since the MME allocates to the UE a single TA ID, i.e. one TA, the UE may traverse multiple TAs within a short period of time when moving at a high speed, as a result, multiple TA update procedures are caused, signaling exchanged between the network and the UE is increased greatly, and network resources are wasted.
In view of the above, an MME allocates a TA List containing multiple TA IDs to a UE in the 3GPP EPS system. Since the TA List includes multiple TA IDs, the range of areas allocated for the UE is increased, so that the TA updates during the movement of the UE are reduced and the utilization of the network resources are improved.
To allocate a TA List for the UE, it is necessary for the MME to determine as possible the area that the UE is moving to so that an appropriate TA List is allocated to the UE in order to reduce as possible the location updates caused during the fast movement of the UE.
At present, however, the MME allocates a new TA List for the UE based on a single TA ID in the original TA List that is sent by the UE, which is insufficient for the MME to allocate a new appropriate TA List for the UE. Therefore, the areas allocated by the MME for the UE are possibly inappropriate and multiple location updates are caused during the fast movement of the UE, thus, a large amount of signaling is still exchanged between the network and the UE, and the network processing resources are still wasted.
SUMMARY OF THE INVENTION
Embodiments of the invention provide a method and apparatus for allocating a Tracking Area List for a User Equipment, to reduce the amount of signaling exchanged between the network and the User Equipment and improve the utilization of network resources.
An embodiment of the invention provides a method for allocating a new Tracking Area List for a User Equipment, including: receiving a designated Tracking Area Identity from the User Equipment; obtaining history information when old Tracking Area List is allocated from an old Mobility Management Entity allocating the old Tracking Area List; and allocating a new Tracking Area List for the User Equipment according to the obtained history information and the received Tracking Area Identity.
An embodiment of the invention provides a Mobility Management Entity, including: a Tracking Area Identity receiving unit adapted to receive a designated Tracking Area Identity from a User Equipment; a history information obtaining unit adapted to obtain history information when the old Tracking Area List is allocated from an old Mobility Management Entity allocating the old Tracking Area List; and a Tracking Area List allocating unit adapted to allocate a new Tracking Area List for the User Equipment according to the obtained history information and the received Tracking Area Identity.
An embodiment of the invention provides a User Equipment including: a receiving unit, which is adapted to receive a Tracking Area Identity of the Tracking Area where the User Equipment is currently located, and receive a Tracking Area List allocated by a Mobility Management Entity; a Tracking Area List information storage and update unit, which is adapted to store and update the Tracking Area List allocated by the Mobility Management Entity according to the Tracking Area List received by the receiving unit; a Tracking Area Identity storage and update unit, which is adapted to store and update a Tracking Area Identity of the Tracking Area where the User Equipment is currently located according to each Tracking Area Identity received by the receiving unit, during the movement of the User Equipment within Tracking Areas covered by the current allocated Tracking Area List; and a sending unit, which is adapted to send to the Mobility Management Entity the Tracking Area Identity stored and updated by the Tracking Area Identity storage and update unit.
In embodiments of the invention, the history information when the old TA List is allocated is added to the UE Context of the old MME allocating the old TA List, and the specific TA ID is sent by the UE to the new MME which is to allocate a new TA List, so that the movement direction and movement speed of the UE is estimated appropriately based on the history information and the TA ID during the allocation of a new TA List, thus an appropriate TA List is allocated to the UE, thereby reducing the amount of signaling exchanged between the network and the UE and improving the utilization of network resources.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic diagram showing a TA List according to an embodiment of the invention;
FIG. 2 is a schematic diagram showing the structure of a Mobility Management Entity according to an embodiment of the invention; and
FIG. 3 is a schematic diagram showing the structure of a User Equipment according to an embodiment of the invention.
DETAILED DESCRIPTION OF THE EMBODIMENTS
As can be seen from the discussion in the background, to allocate a relatively appropriate Tracking Area List for a UE, an MME is required to estimate the area that the UE is heading for and the movement speed of the UE. At present, however, depending on one TA ID is sent by the UE, the MME cannot satisfy the requirements of estimating the area that the UE is heading for and the movement speed of the UE and then allocating an appropriate Tracking Area List for the DE. Therefore, in an embodiment of the invention, in order to allocate an appropriate new Tracking Area List for the UE, some history information of the old allocated Tracking Area List (i.e. the Tracking Area List allocated for the UE just before any new Tracking Area List is allocated) is respectively stored in the old MME and the UE, enabling the new MME to estimate the area that the UE is heading for and the movement speed of the UE, thereby reducing the amount of signaling exchanged between the UE and network side during the fast movement of the UE and improving the utilization of the network resources.
Preferably, given that the old MME which has allocated the old Tracking Area List for the UE is denoted by MME 1 and the new MME which allocates a subsequent new Tracking Area List for the UE is denoted by MME 2 , MME 1 and MME 2 may be physically the same MME or different MMEs. During the mobility management, which may include for example a TA update procedure and an attachment procedure, when the UE accesses MME 2 , the UE provides a TA ID from its old Tracking Area List for MME 2 ; in this case, MME 2 receives the TA ID provided by the UE, obtains the UE Context from MME 1 , and allocates a new Tracking Area List for the DE based on the TA ID provided by the UE and the UE Context obtained from MME 1 . In view of this, in an embodiment of the invention, some additional history information when the old Tracking Area List is allocated is stored by MME 1 in the UE Context in MME 1 , and the TA ID sent by the UE to the MME 2 is further defined, to thereby enable MME 2 to allocate a relatively appropriate new Tracking Area List for the UE based on the history information in the UE Context and the further defined TA ID.
The implementation, embodiments and corresponding beneficial effects of the solution of the invention are described below in detail in connection with the Drawings.
An implementation of the invention includes: receiving a designated TA ID sent by a UE; obtaining history information when the old Tracking Area List is allocated from the old Mobility Management Entity which has allocated the old Tracking Area List; and allocating a new Tracking Area List for the UE based on the obtained history information and the received TA ID.
The history information refers to such information that is used for determining the area traversed by the UE, the movement speed of the UE, the direction in which the UE is moving, and so on, and includes, but not limited to the old allocated Tracking Area List (the following description is given by taking the TA List as an example), the time when the old TA List is allocated, the TA ID of the TA where the UE is located when the old TA List is allocated, and so on.
Further, since the TA ID received by the new MME in the prior art is disadvantageous for determining the area that the UE is heading for, the TA ID from the UE is such defined in an embodiment of the invention that the TA ID sent by the UE is a specific TA ID in the old TA List, for example, the TA ID of the TA where the UE is located when the area covered by the old TA List is visited for the last time, i.e. the Last Visited Registered TAI.
Since the UE Context is stored in the MME, the MME can store the history information above to its stored DE Context after allocating a TA List for the UE. Examples of storing the history information to the UE Context by the MME are described below, and an additional parameter is added as history information depending on actual application in particular embodiments.
After allocating the old TA List (i.e. the allocated TA List just preceding any new TA List is allocated) for the UE, MME 1 stores the allocated old TA List, the allocation time of the old TA List, and the TA ID of the TA where the UE is located when the old TA List is allocated, in the UE Context corresponding to the UE.
To allocate a new TA List for the UE, MME 2 calculates a time interval between the current time and the old allocation time when MME 1 allocates the old TA List that is obtained from the UE Context stored in MME 1 , and determines a distance between the TA where the UE is currently located and the TA where the UE is located when the old TA List is allocated by MME 1 , based on the TA ID of the TA where the UE is located when the old TA List is allocated that is obtained from the UE Context.
Subsequently, MME 2 estimates the movement speed of the UE based on both the time interval and the distance that are determined above. If the UE covers a relatively long distance within a relatively short time interval, the movement speed of the DE is determined as high, and thus a new TA List with a relatively large coverage is allocated for the UE; otherwise, if the UE covers a relatively short distance within a relatively long time interval, the movement speed of the UE is determined as low, and thus a TA List with a relatively small coverage is allocated for the UE.
If the UE does not move directly from the old TA where the UE is located when the old TA List is allocated by MME 1 to the TA where the UE is currently located (for example, the UE moves from the old TA to another TA and then to the current allocated TA), an error may be present in the movement speed of the UE determined above. In this case, the movement speed is adjusted based on the old TA List allocated by MME 1 to decrease the error. For example, a weight is determined with reference to the allocated old TA List, and the movement speed is multiplied by the weight to decrease the error in the movement speed. Therefore, the old TA List allocated by MME 1 is required to be added to the UE Context. The significance of the old TA List allocated by MME 1 is related to the time interval obtained above. Typically, the smaller the time interval is, the more significant the old TA List is; vice versa, the longer the time interval is, the less significant the old TA List is. For example, when the time interval obtained above is one week, the old TA List is substantially of no significance, and generally cannot be used for estimating the movement speed of the UE; and when the time interval obtained above is five minutes, the old TA List is referred to for the calculating of the movement speed of the UE.
For the calculation of the time interval above, the time of MME 1 needs to be in synchronization with that of MME 2 , otherwise, the time interval calculated may be inaccurate. However, such synchronization need not have a high precision, and synchronization in the order of a second satisfies embodiments of the invention. Various manners can be used for synchronization in the prior art, for example, the synchronization in the order of a second is implemented through the Network Time Protocol (NTP) defined by the Internet Engineering Task Force (IETF).
As describe above, to enable MME 2 to determine whether it is necessary to refer to the old TA List for the allocation of a new TA List for the UE with respect to a certain range of time interval, it is possible to define such a rule that MME 2 refers to the old TA List for the allocation of a new TA List for the UE if the obtained time interval is shorter than or equal to a preset time interval, and otherwise, MME 2 does not refer to the old TA List that has been allocated by MME 1 . Here, the preset time interval is set by the operator on its own initiative in various ways, for example, the preset time interval is set as N*MRC_Timer, where N denotes a natural number and MRC_Timer denotes the time set by a Mobile Reachable timer of the DE, and the operator sets the value of N and MRC_Timer depending on a practical application.
In addition to the history information as described above, a movement track of the UE is important for allocating a new TA List for the UE. Currently, a single TA ID is sent by the UE to the new MME and it is impossible to obtain an accurate movement track of the UE by using the single TA ID. However, the TA ID to be sent by the UE is further such defined that a specific TA ID that facilitates the determination of the movement direction of the UE is sent by the UE, for example, the UE sends the TA ID of the TA located for the last time within the old TA List allocated by MME 1 , i.e. the Last Visited Registered TM, so that the movement direction of the UE is determined by MME 2 by combining the designated TA ID sent by the UE and the TA ID of the TA where the UE is currently located. Particularly in an embodiment of the invention, when moving within the areas covered by the old TA List, the UE stores the TA ID of each TA where it accesses into its Universal Subscriber Identity Module (USIM) or nonvolatile storage of the DE although no TA update occurs, and replaces a previous TA ID if the previous TA ID is already stored. In this way, when a TA update procedure is initiated by the UE, the TA ID currently stored in the UE is the TA ID of the TA where the UE is located when the old TA List is accessed for the last time, and MME 2 determines the movement direction of the UE by referring to both the designated TA ID provided by the UE and the TA ID of the TA where the UE is currently located, thereby facilitating the allocation of a new relatively appropriate TA List for the UE.
FIG. 1 is a schematic diagram showing the TA List according to an embodiment of the invention. An embodiment of allocating a new TA List is described below in connection with FIG. 1 .
When a UE moves to an area TA 1 , MME 1 allocates a TA List of “TA 1 , TA 2 , . . . , TA 6 ” for the UE, and then adds the allocated TA List, the allocation time of the TA List and the TA ID of the TA where the UE is located when the TA List is allocated (i.e. TA 1 ) to the UE Context corresponding to this UE; in addition, the UE stores the TA ID of the TA where it is currently located (i.e. TA 1 ) into its USIM or nonvolatile storage, and stores the allocated TA List into its volatile storage such as a memory.
Since the network side allocates a new TA List for a DE when the UE attaches to the network again after its detachment (such as power off), it is preferable in the embodiment of the invention to store the allocated TA List into the volatile storage of the UE, that is, the TA List does not exist in the UE after the detachment of the UE. Alternatively, the TA List is stored in the nonvolatile storage of the UE.
When moving out of the area TA 1 , the UE determines whether the TA ID of the TA where it moves to is within the old TA List, if so, the UE does not initiate a TA update and stores the TA ID of the TA where it moves to into its USIM or nonvolatile storage to replace the existing TA 1 . If the UE determines that the TA ID of the TA where it moves to is not within the old TA List, a TA update procedure is initiated, after the TA Update procedure is finished, the UE stores the TA ID of the TA where it moves to into its USIM or nonvolatile storage after the TA update.
For example, when moving to an area TA 2 , the DE determines that TA 2 is within the old TA List and conducts no TA update, and stores the TA ID of the TA where it is currently located (i.e. TA 2 ) into its USIM or nonvolatile storage to replace TA 1 .
Likewise, when the UE moves further to an area TA 3 , the UE stores TA 3 into its USIM or nonvolatile storages to replace TA 2 .
When moving further to an area TA 7 , the UE determines that TA 7 is not within the old TA List including TA 1 -TA 6 , and then sends to MME 2 a TA Update Request message, which contains a TA ID (i.e. TA 3 ) stored in the USIM or nonvolatile storage of the UE and an EPS Temporary Mobile Station Identity (S-TMSI).
After receiving the TA Update Request message from the UE, MME 2 locates MME 1 according to the TA 3 and S-TMSI contained in the message, obtains the UE Context corresponding to the UE from MME 1 , and extracts the old TA List (i.e. TA 1 -TA 6 ), the allocation time of the old TA List and the TA ID of the TA where the UE is located when the old TA List is allocated from the UE Context.
In the case that MME 2 and MME 1 are the same MME physically, after receiving the TA Update Request message from the UE, MME 2 locates MME 1 according to the S-TMSI contained in the message, searches for the UE Context corresponding to the UE in the located MME 1 , and extracts the old TA List (i.e. TA 1 -TA 6 ), the allocation time of the old TA List and the TA ID of the TA where the UE is located when the old TA List is allocated from the UE Context.
Subsequently, MME 2 allocates a new TA List for the UE according to the history information extracted as described above as follows.
According to the current time and the extracted allocation time of the old TA List allocated by MME 1 , MME 2 calculates the time interval between the current time and time when the old TA List is allocated by MME 1 , and determines whether the time interval is shorter than the preset time interval; if so, MME 2 allocates a new TA List for the UE with reference to the extracted old TA List; otherwise, MME 2 allocates a new TA List for the UE without reference to the extracted old TA List. It is assumed that the calculated time interval is shorter than the preset time interval in the embodiment, and the extracted old TA List is used for the allocation of the new TA List.
Then, MME 2 estimates the movement speed of the UE by using the distance between the areas TA 1 and TA 7 (for example, the distance is calculated from related parameters configured by the operator) and the calculated time interval, determines a weight according to the extracted old TA List, and adjusts the estimated movement speed based on the determined weight to obtain a more accurate movement speed.
If the adjusted movement speed is relatively high, it is determined to allocate a relatively large coverage for the UE; otherwise, a relatively small coverage is allocated for the UE. It is assumed that the determined movement speed of the UE is low in the embodiment, and hence MME 2 determines to allocate a relatively small coverage of Tracking Areas, e.g. three TAs, for the UE.
Subsequently, according to the area TA 3 provided by the UE in the TA update request message and TA 7 where the UE initiates the TA update procedure, MME 2 determines that the UE is moving in an inclining direction from the area TA 3 to area TA 7 , and hence allocates Tracking Areas for the UE along such direction.
In this case, MME 2 allocates a new TA List, i.e. a TA List 2 of “TA 3 , TA 7 , TA 8 ”, for the UE.
After allocating TA List 2 for the UE, MME 2 adds the allocated TA List 2 , the allocation time of the TA List 2 , and the TA ID of the TA (i.e. TA 7 ) where the UE is located when the TA List 2 is allocated to the UE Context, replacing the existing history information.
Additionally, the UE determines that TA 7 is contained in the new allocated TA List 2 , stores TA 7 in the USIM or nonvolatile storage of the UE to replace TA 3 , and stores the TA List 2 into the memory of the UE to replace the old TA List allocated by MME 1 previously.
Thus, the allocation of the new TA List is completed.
Corresponding to the method for allocating the TA List described above, an embodiment of the invention further provides a Mobility Management Entity. FIG. 2 is a schematic diagram showing the structure of the Mobility Management Entity according to an embodiment of the invention, as shown, the Mobility Management Entity 10 includes:
a Tracking Area Identity receiving unit 11 which is adapted to receive a designated TA ID from a UE;
a history information obtaining unit 12 which is adapted to obtain history information when the old TA List is allocated from a old Mobility Management Entity allocating the old TA List; and
a Tracking Area List allocating unit 13 which is adapted to allocate a new TA List for the UE according to the obtained history information and the received designated TA ID.
If the old TA List, the allocation time of the old TA List and the TA ID of the TA where the UE is located when the old TA List is allocated are included in the history information, the Tracking Area List allocating unit 13 estimates the movement speed of the UE according to the allocation time and the TA ID when the new TA List is allocated, and determines the moving direction of the UE according to the TA ID of the TA where the UE is currently located and the designated TA ID sent by the UE. Thus, the Tracking Area List allocating unit 13 includes:
a subunit adapted to determine the movement direction of the UE according to the TA ID of the TA where the UE is currently located and the designated TA ID sent by the UE;
a subunit adapted to estimate the movement speed of the UE according to the obtained history information; and
a subunit adapted to allocate a new TA List according to the determined movement direction of the UE and the estimated movement speed of the UE.
The subunit adapted to estimate the movement speed of the UE according to the obtained history information includes:
a subunit adapted to calculate a time interval between the current time and the allocation time when the new Tracking Area List is allocated;
a subunit adapted to calculate a distance between a Tracking Area where the UE is currently located and a Tracking Area where the UE is located when the old Tracking Area List is allocated, according the Tracking Area Identity of the Tracking Area where the UE is currently located and the Tracking Area Identity of the Tracking Area where the UE is located when the old Tracking Area List is allocated; and
a subunit adapted to estimate the movement speed of the UE according to the calculated time interval and the estimated distance.
Additionally, since the UE might move to the same TA again during the movement within the areas covered by the old TA List, an error may be present in the movement speed of the UE estimated according to the above allocation time and the TA ID of the TA where the UE is located at the allocation time. In this case, the movement speed is adjusted based on the old TA List by the subunit which is adapted to estimate the movement speed of the UE according to the obtained history information.
However, since the significance of the old TA List is in inverse proportion to the time interval between the allocation time of the old TA List and the current time, it is necessary to calculate the time interval to determine the significance of the old TA List, and further to adjust the movement speed described above more accurately. Thus, the subunit adapted to estimate the movement speed of the UE according to the obtained history information further includes:
a subunit adapted to determine whether the calculated time interval is shorter than the preset time interval;
a subunit adapted to determine a weight used for adjusting the movement speed of the UE based on the old Tracking Area List allocated for the UE if the calculated time interval is shorter than the preset time interval; and
a subunit adapted to adjust the estimated movement speed of the UE by using the determined weight.
Here, the preset time interval is set according to a practical implementation, and is set as, but not limited to N*MRC_Timer, where N denotes a natural number and MRC_Timer denotes a time parameter set by a Mobile Reachable Timer of the UE.
Further, after allocating a new TA List for the UE, the MME needs to store the related history information to the UE Context corresponding to the UE.
An embodiment of the invention further provides a User Equipment. FIG. 3 is a schematic diagram showing the structure of a User Equipment according to an embodiment of the invention, as shown, the User Equipment 20 includes:
a receiving unit 21 , which is adapted to receive a Tracking Area Identity of the Tracking Area where the User Equipment is currently located, and receive a Tracking Area List allocated by a Mobility Management Entity;
a Tracking Area List information storage and update unit 22 , which is adapted to store and update the Tracking Area List allocated by the Mobility Management Entity according to the Tracking Area List received by the receiving unit 21 ;
a Tracking Area Identity storage and update unit 23 , which is adapted to store and update a Tracking Area Identity of the Tracking Area where the User Equipment is currently located according to each Tracking Area Identity received by the receiving unit 21 , during the movement of the User Equipment within Tracking Areas covered by the old allocated Tracking Area List; and
a sending unit 24 , which is adapted to send to the Mobility Management Entity the Tracking Area Identity stored and updated by the Tracking Area Identity storage and update unit 23 .
The TA List stored and updated by the Tracking Area List information storage and update unit 22 is stored in a volatile storage (such as a memory) or a nonvolatile storage of the User Equipment. Further, since the TA List is no longer used after the detachment or power off of the User Equipment, it is preferable to store the received TA List in the volatile storage such as the memory of the User Equipment, and the stored TA List is lost automatically when the User Equipment is powered off.
In either case that the TA List is stored in a volatile storage or a nonvolatile storage, the UE deletes the TA List or indicate the TA List as invalid, and the TA List is no longer used. Accordingly in this case, the Tracking Area List information storage and update unit 22 includes:
a subunit adapted to store the Tracking Area List in the volatile or nonvolatile storage; and
a subunit adapted to indicate the Tracking Area List stored in the volatile or nonvolatile storage as invalid or delete the Tracking Area List when the User Equipment is detached or powered off
The Tracking Area Identity storage and update unit 23 stores the TA ID into the USIM or nonvolatile storage of the UE.
It shall be noted that the above embodiments are merely used to illustrate the solution of the invention without limitation. While the invention has been described with reference to the embodiments, it will be appreciated by those skilled in the art that various modifications and alterations may be made to the solutions in the embodiments of the invention without departing from the scope of the invention.
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A method of allocating the moving area list of user equipment which relating to wireless communication technology. Interacting signaling between network and UE is reduced. The utilization efficiency of network resource is enhanced. The method includes, receiving the area ID which is pre-defined from UE, acquiring the history information of the last allocated moving area list from the mobility management entity (MME) which allocated the last moving area list, allocating new moving area list according to the history information and the received area ID. Accordingly, a MME and UE are disclosed.
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FIELD OF THE INVENTION
[0001] The present invention relates generally to the data processing field, and more particularly, relates to method and apparatus for implementing deployment of a virtual machine (VM) in a cloud environment including VM boot profiling used for the VM image download prioritization.
DESCRIPTION OF THE RELATED ART
[0002] In deploying a virtual machine (VM) in a cloud environment, the part of the process that takes the longest is the transfer of the image from some repository, for example, Glance in OpenStack, to the hosting platform, for example to a boot disk from which the VM must boot and operate.
[0003] One example technique to mitigate the VM image transfer time includes prefetching VM images to the host. In order to be optimal, all possible images should be stored locally on the host. This becomes more difficult and expensive, both in terms of hardware and bandwidth, as the number and diversity of such images increases; and it makes maintenance of the images difficult.
[0004] Another technique to mitigate the VM image transfer time includes caching images closer to the target host. Again, this uses bandwidth and hardware proportional to the number of VM images in play; and it still ultimately requires transfer of the image to the host prior to VM boot.
[0005] Another technique to mitigate the VM image transfer time includes using copy-on-write (COW) file systems to allow quick pseudo-cloning of an image already deployed locally. This works great as long as many VMs will share the same image; however, it does not help for the first VM deployed on that host, for which the entire image must still be transferred.
[0006] A need exists for an efficient and effective method and apparatus for implementing deployment of a virtual machine (VM) in a cloud environment including transfer of the VM image.
SUMMARY OF THE INVENTION
[0007] Principal aspects of the present invention are to provide a method and apparatus for implementing enhanced deployment of a virtual machine (VM) in a cloud environment. Other important aspects of the present invention are to provide such method and apparatus substantially without negative effects and that overcome many of the disadvantages of prior art arrangements.
[0008] In brief, a method and apparatus are provided for implementing enhanced deployment of a virtual machine (VM) in a cloud environment. VM boot profiling is performed and used for providing VM image download prioritization. The VM boot profiling facilitates the transfer of the earliest needed portions of the VM image first, allowing the VM to boot and begin operating quickly while the later needed portions of the VM image are still transferring.
[0009] In accordance with features of the invention, the VM boot profiling includes high level summary logging of an order and files that are accessed during boot time to be used by other processes to improve image transfer performance for booting.
[0010] In accordance with features of the invention, the VM boot profiling includes logging an order and location of files that are accessed at boot time.
[0011] In accordance with features of the invention, the VM boot profiling includes organizing the files for optimal transfer at boot time.
[0012] In accordance with features of the invention, the VM boot profiling includes marking check points in the boot process.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The present invention together with the above and other objects and advantages may best be understood from the following detailed description of the preferred embodiments of the invention illustrated in the drawings, wherein:
[0014] FIG. 1 is a block diagram of an example computer system for implementing enhanced deployment of a virtual machine (VM) in a cloud environment in accordance with the preferred embodiment;
[0015] FIGS. 2A and 2B are flow charts together illustrating example operations for implementing virtual machine (VM) profiling in accordance with the preferred embodiment;
[0016] FIGS. 3A and 3B are flow charts together illustrating example operations for implementing virtual machine (VM) coordinated parallel boot process in accordance with the preferred embodiment; and
[0017] FIG. 4 is a block diagram illustrating a computer program product in accordance with the preferred embodiment.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0018] In the following detailed description of embodiments of the invention, reference is made to the accompanying drawings, which illustrate example embodiments by which the invention may be practiced. It is to be understood that other embodiments may be utilized and structural changes may be made without departing from the scope of the invention. In particular, references to “file” should be broadly considered to include and may be substituted with block, page or any other logical subdivision of data,
[0019] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.
[0020] In accordance with features of the invention, a method and apparatus are provided for implementing enhanced deployment of a virtual machine (VM) in a cloud environment. VM boot profiling is performed for providing VM image download prioritization. The VM boot profiling includes high level summary logging the order and files that are accessed during boot time to be used by other processes to improve image transfer performance for booting.
[0021] Having reference now to the drawings, in FIGS. 1 , there is shown a computer system embodying the present invention generally designated by the reference character 100 for implementing enhanced deployment of a virtual machine (VM) in a cloud environment, in accordance with the preferred embodiment. Computer system 100 includes one or more processors 102 or general-purpose programmable central processing units (CPUs) 102 , # 1 -N. As shown, computer system 100 includes multiple processors 102 typical of a relatively large system; however, system 100 can include a single CPU 102 . Computer system 100 includes a cache memory 104 connected to each processor 102 .
[0022] Computer system 100 includes a system memory 106 . System memory 106 is a random-access semiconductor memory for storing data, including applications and programs. System memory 106 is comprised of, for example, a dynamic random access memory (DRAM), a synchronous direct random access memory (SDRAM), a current double data rate (DDRx) SDRAM, non-volatile memory, optical storage, and other storage devices.
[0023] I/O bus interface 114 , and buses 116 , 118 provide communication paths among the various system components. Bus 116 is a processor/memory bus, often referred to as front-side bus, providing a data communication path for transferring data among CPUs 102 and caches 104 , system memory 106 and I/O bus interface unit 114 . I/O bus interface 114 is further coupled to system I/O bus 118 for transferring data to and from various I/O units.
[0024] As shown, computer system 100 includes a storage interface 120 coupled to storage devices, such as, a direct access storage device (DASD) 122 , and a CD-ROM 124 . Computer system 100 includes a terminal interface 126 coupled to a plurality of terminals 128 , # 1 -M, a network interface 130 coupled to a network 132 , such as the Internet, local area or other networks, shown connected to another separate computer system 133 , and a I/O device interface 134 coupled to I/O devices, such as a first printer/fax 136 A, and a second printer 136 B.
[0025] I/O bus interface 114 communicates with multiple I/O interface units 120 , 126 , 130 , 134 , which are also known as I/O processors (IOPs) or I/O adapters (IOAs), through system I/O bus 116 . System I/O bus 116 is, for example, an industry standard PCI bus, or other appropriate bus technology.
[0026] System memory 106 stores an operating system 140 , system image files 1 -Z, 142 , image event log entries 144 , an agent 146 for generating profiles, a profiling and boot control program 148 in accordance with the preferred embodiments.
[0027] In accordance with features of the invention, in an illustrative embodiment of VM boot profiling such as shown in FIGS. 2A and 2B , instrumenting of low-level file accessors of the operating system in an image in question is performed. In this case, for example assuming a C-based kernel using stat( ) and open( ) calls, and the idea in general is to find a narrow choke-point that will catch all file accesses during the boot process. As the system boots, the instrumented hooks make a log of each file name as it is accessed, along with the time stamp at which this occurred. Meanwhile, some other mechanism is identifying significant (in the eye of the user) operating system events as they occur. This other mechanism might be instrumentation in some other syscall or program, for example, “ifup” for the network event, some program that runs and watches for a particular condition, such as, a ping loop to detect when networking comes up, or even a human. When a significant event occurs, the mechanism makes an entry in the same log, giving the event a tag for later use, and a timestamp. This continues until all events of interest have occurred.
[0028] Referring now to FIGS. 2A and 2B , there are shown example flow charts together illustrating example operations for implementing virtual machine (VM) profiling generally designated by the reference character 200 in accordance with the preferred embodiment. An agent, such as agent 146 observes a VM as it boots, begins work, and identifies which files are accessed during this process. In this manner, the profiling and boot control program 148 of the present invention can break the image into prioritized chunks of almost any granularity, down to the level of individual files, I/O blocks, memory pages, and the like. Using such an agent, the user of the invention, for example, cloud image administrator advantageously performs a mock deploy against this image to generate its chunk profile. This profile is used in subsequent deploys to prioritize the transfer and startup sequence of the VM.
[0029] As indicated at a block 202 in FIG. 2A , each of files 1 -X is accessed, and as indicated at a block 204 in FIG. 2B , each such access is recorded and timestamped. One example of a mechanism that could achieve this profiling: hook into the VM kernel's low-level stat and/or open syscall and log (to a file, NVRAM, and the like) the file system path from each call. This produces an ordered list of files, which can then be culled for duplicates, preserving only the earliest entry for a given path.
[0030] During the profiling mock deploy of FIGS. 2A and 2B , logging events/checkpoints in the same medium, either automatically, for example, each process as it starts, or based on the input of the user, for example, “here's where it finished booting to the point where I could log in”; “here's where network configuration finished”; “here's where I performed a software update”; “here's where I kicked off the workload”. These checkpoints can be used to schedule which pieces of the VM's workload advantageously are kicked off based on which segments have finished downloading. As indicated at a block 206 in FIG. 2A , networking is active, and as indicated at a block 208 in FIG. 2B , an event, networking active is recorded and timestamped.
[0031] As indicated at a block 210 in FIG. 2A , each of files X+1-file Y is accessed, and as indicated at a block 212 in FIG. 2B , each such access is recorded and timestamped. As indicated at a block 214 in FIG. 2A , a login prompt is identified, and as indicated at a block 216 in FIG. 2B , an event, login prompt is recorded and timestamped.
[0032] As indicated at a block 218 in FIG. 2A , each of files Y+1-file Z is started and opened, and as indicated at a block 220 in FIG. 2B , each such access is recorded and timestamped. As indicated at a block 222 in FIG. 2A , a workload is identified, and as indicated at a block 224 in FIG. 2B , an event, workload is recorded and timestamped. As indicated at a block 226 in FIG. 2A , a next file Z+1 is accessed, and the profiling mock deploy operations are continued.
[0033] In accordance with features of the invention, during Boot, such as shown in FIGS. 3A and 3B , having created the log file once, via VM boot profiling or a Dummy Run in FIGS. 2A and 2B , now booting VMs is performed many times using this same image. The coordinated boot process runs two things in parallel: uploading the image, and a boot controller agent which kicks off various pieces of work. The image is uploaded in chunks in the order specified by the log file. Whenever the upload comes across an event log entry, it sends a notification to the boot controller agent, which now knows the VM is ready for the one or more pieces of work associated with that event. The boot controller continues to run until all the events of interest have been seen, at which point the boot controller exits. The uploader continues to run until the log file has been entirely traversed. At this point, there are typically one or more remaining chunks that have not been uploaded yet, for example, because they were never touched during the VM boot profiling or Dummy Run. The uploader now uploads those remaining chunks in arbitrary order, and then exits. At this point, the VM looks just like it would have under a normal serial full-upload-then-boot.
[0034] Referring to FIGS. 3A and 3B , there are shown example flow charts together illustrating example operations for implementing virtual machine (VM) coordinated parallel boot process generally designated by the reference character 300 in accordance with the preferred embodiment. As indicated at a block 302 in FIG. 3A , operations start to create a VM, resources and the like are allocated as indicated at a block 304 . As indicated at a block 306 in FIG. 3A , a boot device is assigned. As indicated at a block 308 in FIG. 3B , the boot controller operations start. As indicated at a block 310 in FIG. 3A , transfer of boot image begins, and transferring files 1 -File X is performed as indicated at a block 312 . As indicated at a block 314 in FIG. 3A , responsive to an identified event log entry, ready for network is signaled to the boot controller agent. As indicated at a block 316 in FIG. 3B , booting to network is performed. As indicated at a block 318 in FIG. 3A , transferring files X+1-File Y is performed and ready for login is signaled as indicated at a block 320 . As indicated at a block 322 in FIG. 3B , waiting is performed, then login is performed as indicated at a block 324 .
[0035] As indicated at a block 326 in FIG. 3A , transferring files Y+1-File Z is performed and ready for workload is signaled as indicated at a block 328 . As indicated at a block 330 in FIG. 3B , waiting is performed, then workload is started as indicated at a block 332 . As indicated at a block 334 in FIG. 3A , transferring files Z+1 is performed, remaining files are transferred as indicated at a block 336 and complete is signaled as indicated at a block 338 . As indicated at a block 332 in FIG. 3B , starting workload is continued.
[0036] Referring now to FIG. 4 , an article of manufacture or a computer program product 400 of the invention is illustrated. The computer program product 400 is tangibly embodied on a non-transitory computer readable storage medium that includes a recording medium 402 , such as, a floppy disk, a high capacity read only memory in the form of an optically read compact disk or CD-ROM, a tape, or another similar computer program product. Recording medium 402 stores program means 404 , 406 , 408 , and 410 on the medium 402 for carrying out the methods for implementing enhanced deployment of a virtual machine (VM) in a cloud environment of the preferred embodiment in the system 100 of FIG. 1 .
[0037] A sequence of program instructions or a logical assembly of one or more interrelated modules defined by the recorded program means 404 , 406 , 408 , and 410 , direct the system 100 for implementing enhanced deployment of a virtual machine (VM) in a cloud environment of the preferred embodiment.
[0038] While the present invention has been described with reference to the details of the embodiments of the invention shown in the drawing, these details are not intended to limit the scope of the invention as claimed in the appended claims.
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A method and apparatus are provided for implementing enhanced deployment of a virtual machine (VM) in a cloud environment. VM boot profiling is performed and used for providing VM image download prioritization. The VM boot profiling facilitates the transfer of the earliest needed portions of the VM image first, allowing the VM to boot and begin operating quickly while the later needed portions of the VM image are still transferring.
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FIELD OF THE INVENTION
[0001] The present invention relates generally to trailers and in one aspect relates to a towable accommodation or storage assembly including an expandable portion.
BACKGROUND OF THE INVENTION
[0002] There are numerous configurations of trailers and caravans current on the market that provide portable accommodation or that provide the means for transporting equipment, such as tents, recreation vehicles and boats. Towable accommodation in the form of camper trailers, caravans, campers, towable RVs and tent trailers are widely used in Australia and the USA.
[0003] There are also trailers that allow for the transportation of recreational vehicles, such as quad bikes, which also include a sleeping cubicle or sealed compartment for storing bedding.
[0004] All of these types of trailers or mobile accommodation units, typically comprise a chassis supported on wheels connected to a respective axle or independent suspension, a drawbar connectable to a towing vehicle and a body fixedly attached to the chassis.
[0005] Many of the trailers and caravans currently on the market include awnings that are configured to provide additional covered living space. Furthermore, there are a number of caravans and campers that include expandable body portions to provide an enlargeable internal living space such as the units disclosed in U.S. Pat. No. 5,090,749 to Counsel, and U.S. Pat. No. 9,597,993 to Pellicer. These expandable body portions typically include a slidable portion that can be slid outwardly when on site and then stored away during transport.
[0006] Existing expandable body portions are however typically configured to retract into the internal space of the caravan or camper trailers, which means that they can impinge upon the existing structures within the caravan or can make packing of the trailer or caravan problematic.
[0007] En-suite caravans have become popular in recent times. However, such caravans are typically larger in length thereby affecting off-road ability and requiring the towing vehicle to have sufficient towing capacity. Alternatively, an en-suite tent can be attached to a side of a camper trailer or caravan, however these typically cannot be accessed from the interior of the tailer or caravan and accordingly lack privacy. Furthermore, such en-suite tents cannot be used at many caravan or trailer park sites since they do not capture or at least direct the grey water in a controlled fashion.
[0008] The phase ‘towable accommodation or storage assembly’ used throughout the specification should be understood to include any type of towable vehicle including, but not limited to, on-road camper trailers, on-road caravans, off-road camper trailers, off-road caravans, tent trailers, RV's, motorhomes, haulage trailers, mobile homes, caravanettes, goods trailers, flatbed trailers, tradesman trailers, storage trailers, car carriers, boat trailer, horse floats or any other type of towable vehicle having a drawbar.
[0009] It should be appreciated that any discussion of the prior art throughout the specification is included solely for the purpose of providing a context for the present invention and should in no way be considered as an admission that such prior art was widely known or formed part of the common general knowledge in the field as it existed before the priority date of the application.
SUMMARY OF THE INVENTION
[0010] It could be broadly understood that the invention resides in a towable accommodation or storage assembly that includes a floor portion that is affixed to or supported on a drawbar, wherein an expansion portion is configured to be pivoted to one side of said floor portion to form at least one wall when said assembly is being used for the purpose of accommodation or utility.
[0011] In one aspect of the invention, but not the broadest or only aspect there is proposed a towable accommodation or storage assembly including, a chassis supported on at least two wheels connected to a respective axle or independent suspension, a drawbar, and a body generally rigidly mounted to said chassis, the towable accommodation or storage assembly being towable behind a towing vehicle, the body having spaced apart first and second sidewalls, a rear wall extending therebetween, a roof attached to upper parts of said sidewalls and rear wall, and a main floor attached to lower parts of said sidewalls and rear wall, an expansion portion, pivotably mounted to, or adjacent a generally vertical front edge of the first sidewall and pivotable to abut a generally vertical front edge of said second sidewall, a fixed first floor portion adjoining or extending outwardly of said main floor, and a movable second floor portion attached to or adjacent the first floor portion and supportable on or above said drawbar, wherein said expansion portion is configured to pivot about a generally vertical axis from a first position wherein the expansion portion abuts or is positioned adjacent said vertical front edge of the second sidewall and covers at least a part of the first floor portion, and a second position wherein at least a part of the first floor portion is exposed and said second floor portion is supported in a generally horizontal orientation on or above the drawbar to thereby provide at least a part of an expanded floor for an expanded living space and the expansion portion forms at least a first side wall of said expanded living space.
[0012] In one form the expanded floor of the expanded living space comprises the first floor portion that is fixed to the chassis or drawbar, and the second floor portion that is hingedly attached to a front edge of the first floor portion and pivotable about a horizontal axis between a generally vertical or oblique orientation and a generally horizontal orientation wherein it is configured to be supported on an upper surface of said drawbar.
[0013] Preferably the expansion portion completely overlays the first floor portion when in said first position, to seal the first floor portion from the ingress of dust. An underside of the expansion portion may include seals to inhibit the ingress of dust and sliders, rollers or wheels to assist in the movement of the expansion portion over said first and/or second floor portions.
[0014] In one form the body may include a front wall that encloses the body to define an internal living or storage space. The front wall may include a door to permit access to the internal living or storage space. In another form the body may include an open front or a movable partition wall. Alternatively, the body may include or comprise a rear flatbed or box tray, or the rear wall of the body may include or comprise a door for accessing the internal living or storage space
[0015] The towable accommodation or storage assembly could therefore be broadly understood to comprise an internal living or storage space at least partially delineated by the body, and an expanded living space that is at least partially delineated by the expansion portion and the expanded floor.
[0016] The front wall of the body or a portion thereof may be movable when the expansion portion is in said second position or between the first and second positions, to permit access between the expanded living space and the internal living or storage space.
[0017] In one form, generally rigid panels are used to form a roof, front wall and second side wall of the expanded living space. The panels are secured in place by relevant clamps, clips or temporary fixing means. The panels that form the roof and walls may be hingedly or slidably attached to the body. In one form the roof panel slidably engages the roof of the body wherein it can be extended when the expansion portion is in the second position.
[0018] In another form, at least some of the walls and/or roof of the expanded living space are constructed from a flexible material, such as but not limited to canvas, PVC or ripstop nylon, wherein zips, elastic cords, press studs, or strips of hook and loop fasters are used to hold the flexible material in place.
[0019] In another form an awning, tunnel tent or gusset may be used to connect the expanded living space to a rear internal space of said towing vehicle. The awning, tunnel tent or gusset may be connected to, or extends over, a rear of said towing vehicle.
[0020] The walls and/or roof of the expanded living space may include a foldable frame wherein as the expansion portion is opening the frame folds out from a storage position to form the walls and/or roof. This automatic deployment of the walls and/or roof may be used to reduce the time of setup. Alternatively, the flexible walls and/or roof may be manually retrieved from a storage cavity and may be clipped or otherwise secured in place. A removable pole/s or frame can be manually located in position in a similar fashion to the tent of some tent trailers.
[0021] The opening and closing of the expansion portion to provide the expanded living space may be undertaken by way of electric or mechanical assistance and include actuators, levers, pulleys, cables or any other necessary apparatus that are required to assist the user in moving the expansion portion. In one form the movement of the expansion portion may be completely automated with appropriate stops and override mechanisms to inhibit damage to any opening/closing apparatus.
[0022] The roof and walls of the expanded living space are configured to interconnect with each other and the expanded floor to thereby provide a generally enclosed expanded living space. The connection devices used to connect the roof and walls preferably provide a barrier to the ingress of water and dust, but in some forms may simply provide connection between the roof, walls and expanded floor without a weather seal to the surrounding environment.
[0023] In one form the fixed first floor portion and hinged second floor portion are generally planar and configured to be positioned on generally the same horizontal plane when being used for accommodation or utility purposes, i.e. kitchen, en-suite.
[0024] In another form the first and/or second floor portions includes at least one part that is sloped to permit drainage. Alternatively, the first and/or second floor portions may be slatted to permit movement of water therethrough into a sump or drain. In the immediately preceding forms the first and/or second floor portions are configured to act as shower base and includes a drainage hole or holes to be used to direct grey water into a detachable hose or a grey water tank.
[0025] The first and/or second floor portions may be rectangular or may conform to the shape of the drawbar and be generally triangular shaped. In the triangular configuration, the expansion portion will be configured to open to around 60° relative to a front vertical plane of the body, or any other suitable angle.
[0026] A movable internal panel attached to the expansion portion or a front portion of the body may be used to provide an internal sidewall for an ablutions cubicle containing a toilet and/or shower and/or basin.
[0027] In another form the internal panel is a bi-fold partition that includes two pivotable parts that are vertically connected and are positionable to form two walls of said ablutions cubicle.
[0028] Preferably the expansion portion includes storage compartments or facilities that can only be accessed from within the expanded living space. In one form the facilities may comprise a toilet, shower or sink with appropriate plumbing. The plumbing may include couplings for connection to a water source or dumping point. The couplings are preferably accessible from an exterior of the expansion portion and may include covers or caps to protect them when not in use.
[0029] In one form when the second floor portion is in a generally upright position it covers the external access points or couplings for the services i.e. power, gas or water couplings. The second floor portion may also be configured to cover a hot water system and/or water filtration system and/or storage area when in the upright position.
[0030] Preferably a door is located in at least one of said walls of the expanded living space to allow access thereto.
[0031] In one form a partition wall may be located between the expanded living space and the internal living or storage space of the body. The partition wall may be movable to fold out from an edge of the body or expansion portion. The partition wall may include a door therethrough or a void or voids to permit access between the expanded living space and the internal living or storage space of the body.
[0032] In another form, there is no barrier between the expanded living space and the internal living or storage space of the body, whereby the expanded living space provides an extension of the internal living or storage space of the body.
[0033] The body may provide a living space including at least one sleeping structure and the expansion portion may provide an expandable en-suite and/or kitchen space. An internal door is preferably used to separate the expandable en-suite from the living space.
[0034] The ablutions cubicle or en-suite may include movable walls wherein the size of the ablutions cubicle may be reduced by moving a wall or walls to access a part of the kitchen space or a storage area.
[0035] In another form, the expandable en-suite may be accessible from an exterior of the towable accommodation or storage assembly through an external door.
[0036] The expansion portion may provide cooking, preparation, eating, storage, sleeping and/or ablutions areas.
[0037] Preferably the hinged second floor portion acts as a stone guard when the towable accommodation or storage assembly is being towed and as a part of the expanded floor of the expanded living space when in an expanded arrangement.
[0038] The second floor portion is hingedly attached to or adjacent a forward edge of the fixed first floor portion. The hinged second floor portion is configured to hinge about a generally horizontal axis between an upright or angled position wherein it protects the expandable accommodation unit from damage by stones, and a lowered position wherein it is configured to rest generally horizontally on, or parallel with, the drawbar to thereby form part of the base of the expanded living space.
[0039] In another form, the second floor portion is slidably connected to or adjacent the first floor portion whereby it can be slid out of a stored position to be supported on or above the drawbar when the expansion portion is in the second position.
[0040] The expansion portion may be generally rectangular in its horizontal cross-sectional profile to thereby limit its footprint when in the first or folded position, whilst maximising the size of the expanded living space when the expansion portion is in the second or extended position.
[0041] Stabilising legs or struts may be used to support the hinged floor portion. Stabilising legs or struts may also support the expansion portion when in the first or open position. The legs or struts are preferably connected to the expansion portion and second floor portion, and can be pivoted or slid into place to support the respective structures. In another form, they may be reversibly attachable thereto.
[0042] Preferably the legs or struts are configured to engage a ground surface and may include feet or the legs, or the struts may be configured to engage receiving brackets on the chassis or drawbar.
[0043] Alternatively, the second floor portion may be supported completely on the drawbar and the expansion portion is supported on the first and/or second floor portions.
[0044] In another aspect of the invention there is proposed a method of providing an expandable portable living space, including the steps of: providing a towable accommodation or storage assembly including a chassis supported on at least two wheels connected to a respective axle or independent suspension, a drawbar for coupling to a towing vehicle for transportation thereof, a body generally rigidly mounted to said chassis, an expansion portion pivotably mounted to, or adjacent said body, and a floor portion or portions mounted to, or supported on, an upper surface of said drawbar; towing said towable accommodation or storage assembly with the expansion portion in a retracted position, to a lodging site; pivoting said expansion portion about a generally vertical axis into an extended position thereby exposing or positioning said floor portion or portions to provide an expanded floor for an expanded living space, the expansion portion forming at least one wall of said expanded living space; and attached or positioning a roof and walls in place to thereby at least partially enclose said expanded living space.
[0045] Preferably when in said retracted position the expansion portion abuts or is at least positioned adjacent a front of said body. The expansion portion may overlay a part of said floor portion or portions.
BRIEF DESCRIPTION OF THE DRAWINGS
[0046] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate an implementation of the invention and, together with the description and claims, serve to explain the advantages and principles of the invention. In the drawings,
[0047] FIG. 1 is a perspective view of a first embodiment of the towable accommodation or storage assembly illustrating an expansion portion in a retracted or closed position;
[0048] FIG. 2 is a perspective view of the towable accommodation or storage assembly of FIG. 1 illustrating the expansion portion in an intermediate position;
[0049] FIG. 3 is a perspective view of the towable accommodation or storage assembly of FIG. 1 in an extended or open position;
[0050] FIG. 4 is a perspective view of a second embodiment of the towable accommodation or storage assembly illustrating in doted lines the walls and roof of the expanded living space;
[0051] FIG. 5 a is a top view of the towable accommodation or storage assembly of FIG. 1 , illustrating the expansion portion in the retracted or closed position;
[0052] FIG. 5 b is a top view of the towable accommodation or storage assembly of FIG. 2 , illustrating the expansion portion in the intermediate position;
[0053] FIG. 5 c is a top view of the towable accommodation or storage assembly of FIG. 3 , illustrating the expansion portion in the extended or open position;
[0054] FIG. 6 is a side view of the towable accommodation or storage assembly illustrating the locking brackets;
[0055] FIG. 7 is a perspective view of a third embodiment of the towable accommodation or storage assembly illustrating a wet area, internal partition wall and internal door;
[0056] FIG. 8 is an underside view of the towable accommodation or storage assembly of FIG. 7 ;
[0057] FIG. 9 is a perspective view of the towable accommodation or storage assembly of FIG. 7 in the fully expanded arrangement with the walls and roof attached;
[0058] FIG. 10 is a perspective view of a fourth embodiment of the towable accommodation or storage assembly illustrating a front boot;
[0059] FIG. 11 is a perspective view of the towable accommodation or storage assembly of FIG. 10 , illustrating the front boot open and the stone guard/second floor portion lowered to reveal a lower storage/couplings/services area;
[0060] FIG. 12 is a side view of a fifth embodiment of the towable accommodation or storage assembly having dual axles;
[0061] FIG. 13 is a perspective view of a sixth embodiment of the towable accommodation or storage assembly illustrating a foldable roof;
[0062] FIG. 14 is a perspective view of a seventh embodiment of the towable accommodation or storage assembly illustrating movable partitions;
[0063] FIG. 15 is a side view of the towable accommodation or storage assembly of FIG. 14 with the roof lifted and a tent attached to encloses the expanded living area;
[0064] FIG. 16 a is a top schematic view of the towable accommodation or storage assembly of FIG. 14 illustrating the partitions in a first position to thereby access the ablutions cubicle;
[0065] FIG. 16 b is a top schematic view of the towable accommodation or storage assembly of FIG. 14 illustrating the partitions in a second position to thereby access the kitchen sink;
[0066] FIG. 17 is a side view of a seventh embodiment of the towable accommodation or storage assembly having a tear-drop shape;
[0067] FIG. 18 is a side view of the towable accommodation or storage assembly of FIG. 17 with part of the roof lifted and tent attached; and
[0068] FIG. 19 is a side schematic view of the towable accommodation or storage assembly of FIG. 17 illustrating the use of an awning to connect the rear of the tow vehicle to the extended living space of the towable accommodation or storage assembly.
DETAILED DESCRIPTION
[0069] Similar reference characters indicate corresponding parts throughout the drawings. Dimensions of certain parts shown in the drawings may have been modified and/or exaggerated for the purposes of clarity or illustration.
[0070] Referring to the drawings for a more detailed description, there is illustrated a towable accommodation or storage assembly 10 , demonstrating by way of examples, arrangements in which the principles of the present invention may be employed.
[0071] FIG. 1 illustrates the towable accommodation or storage assembly 10 including a chassis 12 supported on at least one wheeled axle 14 , a drawbar 16 , and a body 18 rigidly mounted to the chassis 12 . The drawbar 16 includes a hitch 20 for connection to a tow ball 22 of a towing vehicle 24 . The drawbar 16 further includes a jockey wheel 26 . The reader will appreciate that the wheeled axle may alternatively be independent suspension.
[0072] The body 18 includes a main floor 28 spaced apart from a main roof 30 with a rear wall 32 and opposing sidewalls 34 , 36 extending therebetween.
[0073] The towable accommodation or storage assembly 10 further includes an expansion portion 38 that in the present embodiment is pivotably mounted to sidewall 36 by way of a vertically extending hinge 40 . When in the closed of retracted position as illustrated in FIG. 1 the expansion portion 38 is positioned over a fixed first floor portion 42 . It should be appreciated that the fixed first floor portion 42 may be integral with the main floor 28 , as illustrated in FIG. 3 , or may be separate to and abutting a front edge of the main floor 28 .
[0074] The expansion portion 38 is configured to pivot about a generally vertical axis from a first or retracted position as illustrated in FIG. 1 , through an intermediate position, as illustrated in FIG. 2 , to a second or extended position, as illustrated in FIG. 3 , to thereby provide an expanded living space 44 as illustrated in FIG. 4 .
[0075] The towable accommodation or storage assembly 10 includes a hinged second floor portion 46 that in an upright or slanted position may act as a stone guard. The second floor portion 46 is pivotable between an inclined position as illustrated in FIG. 1 wherein it protects the front of the towable accommodation or storage assembly 10 from damage by rocks and debris when being towed, and a generally horizontal position as illustrated in FIGS. 2 to 4 . In the horizontal position the second floor portion 46 rests upon the drawbar 16 and an upper surface forms at least a part of the expanded floor 48 of the expanded living space 44 .
[0076] The reader will now appreciate that the fixed first floor portion 42 and hinged second floor portion/stone guard 46 forms the expanded floor 48 of the expanded living space 44 .
[0077] In the present embodiment, the second floor portion 46 is attached to a front edge of the first floor portion 42 by a horizontally extending hinge 50 .
[0078] As illustrated in FIG. 4 the second floor portion 46 is supported on legs 52 . These support legs 52 may be attached to or deployed from the second floor portion 46 to stabilise the towable accommodation or storage assembly 10 at the front outer corners. The reader should however appreciate that struts (not shown) that engage the drawbar may alternatively be used, or the second floor portion 46 may be sufficiently supported on the drawbar to not require legs or struts.
[0079] As further illustrated in FIG. 4 , the main floor 28 , main roof 30 , rear wall 32 and opposing sidewalls 34 , 36 of the body 18 define an internal living or storage space 54 . This internal living or storage space 54 may include fixed structures, such as a bed 56 , storage draws 58 or other structures typically found in caravans or campers.
[0080] The expanded living space 44 is enclosed by a roof 60 , front wall 62 and sidewall 64 , shown as transparent in FIG. 4 to illustrate the boundaries of the expanded living space 44 .
[0081] The expansion portion 38 also includes fixed structures, such as shelves 66 and a window 68 .
[0082] FIGS. 5 a to 5 c illustrate the expansion portion 38 being pivoted about a generally vertical axis into the expanded or open position. As shown in FIG. 5 a , the expansion portion 38 is positioned in a first or retracted position when being towed behind a towing vehicle 24 . When the towable accommodation or storage assembly 10 is to be used the expansion portion 38 is pivoted through a series of intermediate positions, one of which is illustrated in FIG. 5 b , until it is in a second or extended position as illustrated in FIG. 5 c , whereafter it is locked in place. Once in position the walls 62 , 64 and roof 60 can be attached as previously illustrated in FIG. 4 . The walls 62 , 64 and roof 60 may be constructed from a canvas material or similar. Alternatively, the walls 62 , 64 and roof 60 may be semi-rigid and removably attached in place or may comprise panels that are hingedly or slidably connected to the body 18 or expansion portion 38 and which may be pivoted or slid into place and locked with appropriate fixing means.
[0083] When in a closed or retracted position, as illustrated in FIG. 5 a , during transit the expansion portion 38 covers and seals the floor area 42 beneath it and seals access to the internal living or storage space 54 . Opening of the expansion portion 38 is supported and controlled in stages via interaction with the fixed first floor portion 42 beneath and also the second floor portion 46 .
[0084] The reader should however appreciate that the opening and/or closing of the expansion portion may be undertaken by way of electric or mechanical assistance and include actuators, levers, pulleys, cables or any other necessary apparatus that are required to assist the user in moving the expansion portion, with appropriate stops and override mechanisms to inhibit damage to the apparatus.
[0085] A lower edge of the expansion portion 38 may include sliders, rollers and brush seals (not shown) to permit the smooth opening and closing thereof. When fully open, as illustrated in FIG. 5 c , the outside corner of the expansion portion 38 is latched to the second floor portion 46 to provide horizontal and vertical support.
[0086] As illustrated in FIG. 6 the expansion portion 38 is secured to the body 18 during transport by way of latches 70 , with appropriate seals (not shown) to inhibit ingress of dust or moisture.
[0087] The roof 30 or a portion thereof, may be raised from a lowered position as shown in FIG. 7 into a raised position as illustrated in FIG. 9 . This is commonly referred to in the art as a pop-top configuration. As further shown in FIG. 7 the expanded living space 44 may be used as a wet area having a shower collection tray/drain 72 in the first floor portion 42 for collecting grey water. A fixed partition wall 74 separates a part of the expanded living space 44 from the internal living or storage space 54 . In the present embodiment, the fixed partition wall 74 forms a rear side of the shower recess and is used to mount a showerhead 76 thereto. A pivoted wall portion 78 is configured to act as a sidewall for the shower or as a door between the expanded living space 44 and internal living or storage space 54 . The expansion portion 38 may include a toilet 80 and storage shelves 66 .
[0088] The reader will appreciate that other configurations are possible within the scope of the patent and include, but are not limited to sinks, cooking facilities, sleeping structures, foldable tables and seating.
[0089] As illustrated in FIG. 8 , an exterior of the towable accommodation or storage assembly 10 includes appropriate plumbing and couplings 82 , 84 for connection to inlet pipe 86 in fluid communication with a water source (not shown) and outlet pipe 88 for connection to a dump point (not shown). The couplings 82 , 84 are preferably accessible from an exterior of the expansion portion and may include covers or caps (not shown) to protect them when not in use. In other embodiments, some of the coupling and a hot water system may be concealed behind the second floor portion 46 when it is in the raised position.
[0090] FIG. 9 illustrates the main roof 30 in a raised position and the walls 62 , 64 and roof 60 attached or repositioned to at least partially enclose the expanded living space 44 . A door 90 is located in wall 64 to permit access to the interior of the towable accommodation or storage assembly 10 .
[0091] FIGS. 10 and 11 illustrate an upper front boot 92 with corresponding lid 94 and a lower storage area 96 that is sealed by the second floor portion 46 , as shown in FIG. 10 . The upper front boot 92 and lower storage area 96 include respective seals and latches (not shown).
[0092] As illustrated in FIG. 12 , in another embodiment the chassis 12 is supported on dual axles 14 a , 14 b and a door 97 is located in the rear wall 32 of the body 18 and used to form a ramp to assist in loading a vehicle such as a quad bike into the storage area 54 .
[0093] In another embodiment, as illustrated in FIG. 13 the main roof 30 and roof 60 may be replaced by a single segmented or expandable roof 98 that includes a plurality of segments 100 , 102 , 104 , 106 , 108 , which are configured to cooperate to thereby form the roof of the towable accommodation or storage assembly 10 when expanded. The segments 100 , 102 , 104 , 106 , 108 , may comprise a flexible roof with internal frame (not shown) or the segments may cooperate in such a way as to provide a barrier to the ingress of water and dust.
[0094] Turning to FIGS. 14 to 16 b there is illustrated another embodiment of the towable accommodation or storage assembly 10 that includes an ablutions cubicle 116 formed by movable partition walls 118 , 122 . As shown in FIG. 14 the pivoted wall portion 78 form a door that seals the internal living or storage space 54 . This door 78 may include a lockable handle so that at least the internal living or storage space 54 can be locked up if the towable accommodation or storage assembly 10 is left unattended for a period of time. This would be particular relevant where the expanded living space 44 is at least partially constructed from canvas.
[0095] As further illustrated in FIG. 14 partition wall 118 is attached by hinges 120 and can be either positioned against door 78 when the expansion portion 38 is in the closed position or moved to a position where it forms one of the walls of the ablution cubicle 116 , as illustrated in FIG. 16 a . The partition wall 118 may also act as a door for providing access to the ablutions cubicle 116 and moved as indicated by the arrow and dotted lines of FIG. 16 a.
[0096] The partition wall 122 in the present embodiment is bi-fold and includes panels 124 , 126 , hingedly attached by hinges 128 and 130 .
[0097] The first floor portion 42 in the present embodiment is slatted and includes slots 132 that fluidly connect the upper surface of the first floor portion 42 with the collection tray/drain 72 . The reader should appreciate that the second floor portion 46 may similarly be slatted.
[0098] The present embodiment includes a kitchen module 134 that is located within the expansion portion 38 . The kitchen module 134 includes a bench 136 or preparation area and, although not illustrated, may include shelves, a fridge, microwave or other kitchen appliances or infrastructure.
[0099] As illustrated in FIG. 15 the expanded living area 44 is enclosed by a flexible tent 138 , such as, but not limited to canvas. The tent 138 is stored within a roof cavity (not shown) when not in used and when the roof 30 is lifted the tent 138 is pulled out and attached around an edge to the floor 42 , 46 , expansion portion 38 and wall 34 by way of zips, clips or other fastening devices. The tent 138 is supported by poles 140 a , 140 b and includes door 90 .
[0100] FIGS. 16 a and 16 b show two different top schematic views of the layout of the towable accommodation or storage assembly 10 . In FIGS. 16 a the panels 124 , 126 of the partition wall 122 are positioned so that a user can have full access to the ablutions cubicle 116 . In this arrangement panel 126 abuts or at least conceals part of the kitchen 134 . As further illustrated in FIG. 16 a the partition wall 118 can be moved in the direct of the arrow to act as a door to provided assess to the toilet 80 and shower 76 . Any water that falls onto the floor 42 passes through the slots 132 into the drain 72 .
[0101] When the user wants full access to the kitchen 134 , the panels 124 , 126 of the partition wall 122 can be pivoted around hinges 128 , 130 and repositioned into the arrangement as illustrated in FIG. 16 b . In this configuration, a kitchen sink 142 that is attached to the rear side of panel 126 is exposed for use.
[0102] As further illustrated in FIGS. 16 a , 16 b the internal living space 54 may include a raised double bed 144 and benches 146 , 148 at a lower level which extend under bed 144 and can be converted into individual single beds. A table 150 is locatable between the benches 146 , 148 and can be slid under the bed 144 when not required as illustrated by the arrow in the figures.
[0103] In another embodiment, as illustrated in FIGS. 17 to 19 , there is provided what is commonly referred to as a tear drop camper configuration. Typically, in the prior art a tear drop camper will open rearwardly and the bed will be located at a front of the body. In the present invention, the bed 144 is located at a rear of the body 18 , as illustrated in FIG. 17 and a portion 152 of the roof 30 is configured to open to provide access to the front of the body 18 , as illustrated in FIG. 18 .
[0104] The tent 138 can then be retrieved from within the roof cavity and be supported by poles 140 a , 140 b as previously discussed. The tent 138 may also include an awning 154 that extends outwardly or connects thereto as illustrated in FIG. 19 . The awning 154 is connected to, or extends over, a rear of the towing vehicle 24 . In this way, the towable accommodation or storage assembly 10 is connected directly to the towing vehicle 24 and the expanded living space 44 can act as a foyer or intermediate area between the towing vehicle 24 and the towable accommodation or storage assembly 10 , thereby allowing covered access to the rear of the towing vehicle 24 through a window 156 or by opening the rear door of the vehicle 24 . This is particularly beneficial if a bedding area, storage draws or a fridge are located in the rear of the vehicle 24 .
[0105] The skilled addressee will now appreciate the advantages of the illustrated invention over the prior art. In one form the invention provides a second floor portion that is fixed on its lower horizontal edge with a hinge so it can be lowered forwardly over the drawbar to thereby create a forward expanded floor area over space that is normally void due to the required towing vehicle's turning clearance. Accordingly, the present invention uses space that is typically not utilises in existing caravans, campers and the like.
[0106] The expansion portion 38 can be swung open to expand the footprint of the towable accommodation or storage assembly 10 to one side. The expansion portion 38 can also be partially opened to access the interior of the towable accommodation or storage assembly 10 such as at a roadside stop. Accordingly, the present invention provides benefits or at least a useful alternative to current caravan and camper configurations.
[0107] Various features of the invention have been particularly shown and described in connection with the exemplified embodiments of the invention, however it must be understood that these particular arrangements merely illustrate the invention and it is not limited thereto. Accordingly, the invention can include various modifications, which fall within the spirit and scope of the invention.
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There is proposed a towable expandable accommodation or storage assembly that includes a floor portion that is affixed to or supported on a drawbar, wherein an expansion portion is configured to be pivoted to one side of said floor portion to form at least one wall when the assembly is being used for the purpose of accommodation or utility. The assembly may provide a collapsible ablutions cubicle or kitchen area that can be reduced in size during transportation of the assembly. In this way, the assembly can be towed to a site and expanded to provide an expanded living area. Furthermore, the configuration of the floor portion means that grey water can be captured for the ablutions cubicle or kitchen area for storage in a tank or to be directed to a drain.
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OTHER RELATED APPLICATIONS
The present application claims priority of Provisional Application No. 61/177,806, filed on May 13, 2009, which is hereby incorporated by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to electronic accessories, and more particularly, to portable device shells for portable electronic devices.
2. Description of the Related Art
Numerous hybrid mobile devices like the “IPHONE”/“IPOD”, “BLACKBERRY”, “GOOGLE's ANDROID”, and others have emerged as an efficient platform for communications. Sometimes the use of some applications might be cumbersome because of an actual physical design of the device. The “IPHONE” for example, is a good phone and mobile communications platform, but the device is often difficult to handle while using as a remote control and within gaming applications. Several applications exist that transform the “IPHONE” into a universal remote control. These applications usually require the “IPHONE” to be used in landscape mode making it difficult to use. The finish of the “IPHONE” is also slippery when holding the phone for extended periods of time and when channel surfing.
A solution to this issue is a hardware “shell” that will accommodate the “IPHONE” to make it easier to use and operate.
Applicant believes that one of the closest references corresponds to U.S. Pat. No. 7,612,997 (B1) issued to Diebel, et al. on Nov. 3, 2009 for a portable electronic device case with battery. However, it differs from the present invention because Diebel, et al. only teaches a case for an electronic device that protects and extends the battery life of the electronic device. The case has a lower case portion and an upper case portion, which assemble together to protect the top, side, and bottom edges of the electronic device. The lower case portion includes a battery to extend the battery life of the electronic device.
Applicant believes that another reference corresponds to U.S. Pat. No. 7,376,441 (B2) issued to Lee on May 20, 2008 for an apparatus and method of interacting with a mobile phone using a TV system. However, it differs from the present invention because Lee teaches an apparatus and a method for interacting with a mobile telephone. A remote control unit receives a user command and transmits it to a TV system, which recognizes the user command as a telephone function command and transmits the function command to the mobile telephone if the TV system is set to Telephone Mode. The TV system may also output data received from the mobile telephone in response to the transmitted function command. A user may interact with a mobile telephone using an interactive TV system by displaying text/image data received from the telephone and by inputting various telephone function commands using a remote control unit. Upon receiving a function command from the TV system, the mobile telephone generates output data in response to the function command and transmits into the TV system. A display unit of the TV system displays the text/image data, and a speaker outputs the sound data. As a result, a user may interact with a mobile telephone using a display unit and a speaker of an interactive TV system with a remote control unit.
Applicant believes that another reference corresponds to U.S. Pat. No. 6,445,933 (B1) issued to Pettit on Sep. 3, 2002 for a tele-remote telephone and remote control device. However, it differs from the present invention because Pettit teaches a teleremote device including a cordless or cellular telephone in combination with a remote controller for a television, VCR, satellite receiver, DVD device, and/or video game controller. The telephone and remote control device are provided in a single rechargeable unit. The device includes a telephone keypad on one side of the device, and a remote control keypad on the other side. To avoid accidental or inadvertent actuation of keys on one side of the device while intending use of the other side, a switch control element is provided to permit selective actuation of the telephone keypad or the remote control keypad. An off switch is provided to conserve battery power when the teleremote device is not in use. Indicator lights may also be provided to show which side of the device is actuated.
Applicant believes that another reference corresponds to U.S. Pat. No. 6,192,236 (B1) issued to Irvin on Feb. 20, 2001 for an apparatus and method for remote control of accessory devices using a radiotelephone as a receiver. However, it differs from the present invention because Irvin teaches a remote control commands provided to an accessory device utilizing a radiotelephone, such as a cellular telephone, as a receiver, which receives control commands over a wide area cellular network utilizing a remote control adaptor. The adaptor may take the form of a detachable adaptor attaching to the radiotelephone or a remote control battery pack replacing the normal battery pack for the radiotelephone or a connecting station serving as a remote control as well as a battery charger for the radiotelephone. Alternatively, a lock box is provided allowing remote actuated access to a compartment of the lock box. The radiotelephone acts as a receiver providing an audio signal to a tone signal decoder, which passes decoded and converted tone signals to a comparator, which assembles a command for comparison to a predetermined password. Switches are activated responsive to the comparison to control accessory devices. Power may be provided by the switching circuit to accessory devices from the radiotelephone system bus, battery or from a separate power source. A user's radiotelephone may thereby be converted on an as needed basis to operate as a receiver for remote control of accessory devices and readily return to normal use, as a radiotelephone when remote control is no longer required.
Applicant believes that another reference corresponds to U.S. Pat. No. 5,982,355 (B1) issued to Jaeger, et al. on Nov. 9, 1999 for a multiple purpose controls for electrical systems. However, it differs from the present invention because Jaeger, et al. teach an electrical circuit control devices affixed to the front of an electronic image display screen, within the image displaying area, to provide instantly changeable labels and other graphics, which convey information pertaining to operation of the controls. The control devices may be of any of a variety of types that are variously operated by depressing switch buttons, turning a knob, flexing or tilting a joystick or exerting force against an immovable knob. The control devices have compact and durable constructions, which enable the devices to be wholly at the front of the display screen as opposed to extending through openings in a screen. Operator manipulation of the control devices is variously sensed by radio frequency sensors, Hall effect sensors, strain gauge sensors, touch sensitive circuits or electromechanical contacts. A remote control unit controls any of variety of different electronic devices and displays different switch button labels and other graphics during controlling of different ones of the devices. A pivotable earpiece enables the same remote control unit to function as a cellular telephone and a cordless telephone.
Applicant believes that another reference corresponds to U.S. Pat. No. 5,138,649 (B1) issued to Krisbergh, et al. on Aug. 11, 1992 for a portable telephone handset with remote control. However, it differs from the present invention because Krisbergh, et al. teach a remote control for one or more appliances and a telephone handset combined into a single unit. A common keypad is used for both remote control and telephone functions. An appliance control signal is generated in response to the actuation of at least one of the keypad keys. The appliance control signal is transmitted via an infrared communication link. A telephone control signal is generated in response to the actuation of at least one of the keypad keys, and transmitted via an infrared or radio frequency communication link. Telephone audio signals from a microphone and to an earphone are communicated via a radio frequency communication link. The remote control/telephone handset is used in combination with a cable television converter/descrambler or satellite television receiver.
Applicant believes that another reference corresponds to U.S. Patent Application Publication No. 20090163140 (A1), published on Jun. 25, 2009 to Packham, et al. for a biochip electroportator and its use in multi-site, single-cell electroporation. However, it differs from the present invention because Packham, et al. teach a remote access and control system for remotely controlling a wide variety of devices using an application installed in a cell phone in conjunction with a control module in communication with the cell phone and the device. A portal-based access and control system is also disclosed.
Applicant believes that another reference corresponds to U.S. Patent Application Publication No. 20090156251 (A1), published on Jun. 18, 2009 to Cannistraro, et al. for a remote control protocol for media systems controlled by portable devices. However, it differs from the present invention because Cannistraro, et al. teach a flexible remote control protocol for a user with handheld electronic devices and media systems. The handheld electronic device may have remote control functionality in addition to cellular telephone, music player, or handheld computer functionality. The handheld electronic devices may have a touch sensitive display screen. The handheld electronic devices may generate remote control signals from gestures or user input that the handheld electronic device may receive. A media system may receive the remote control signals and may take appropriate action. The handheld electronic device may receive media system state information transmitted by the media system. The handheld electronic device may generate custom display screens when the media system state information is associated with a registered screen identification that has an associated custom display template. The handheld electronic device may generate generic display screens when the media system state information is not associated with a registered screen identification.
Applicant believes that another reference corresponds to U.S. Patent Application Publication No. 20090005167 (A1), published on Jan. 1, 2009 to Arrasvuori, et al. for Mobile Gaming with External Devices in Single and Multiplayer Games. However, it differs from the present invention because Arrasvuori, et al. teach methods, systems and apparatuses for gaming using one or more mobile communication devices and one or more remotely-controllable drones, the one or more mobile communication devices being adapted to remotely-control the one or more remotely-controllable drones; including providing game control software to one or more of the mobile communication devices, the game control software including rules for play affecting the operation of the remotely-controllable drones; and, operating a remotely-controllable drone using the mobile communication device with remote control within the rules of play.
Applicant believes that another reference corresponds to U.S. Patent Application Publication No. 20090064279 (A1), published on Mar. 5, 2009 to Ardolino for a system for secure remote access and control of computers. However, it differs from the present invention because Ardolino teaches a system that anyone with a internet browser can use to set up a high security VPN between a mobile wireless hand-held devices or computer and a remote computer and operate control the remote computer. An automated Internet browser sign-up process sets up a subscription to a VPN service and installs the required software components. A system to provide data and access control security as well as simulating a display, keyboard and mouse on a hand-held device with only a touch screen is also disclosed.
Applicant believes that another reference corresponds to U.S. Patent Application Publication No. 20090088204, published on Apr. 2, 2009 to Culbert, et al. for movement-based interfaces for a personal media device. However, it differs from the present invention because Culbert, et al. teach systems and methods for a media device including one or more movement-based interfaces for interfacing with or controlling the media device.
Applicant believes that another reference corresponds to U.S. Patent Application Publication No. 20080070621 (A1), published on Mar. 20, 2008 to Ou Yang, et al. for a digital cordless phone having remote control functionality. However, it differs from the present invention because Ou Yang, et al. teach a digital cordless phone having remote control functionality, whereby a telephone connection is established upon transmitting and receiving wireless telephony signals by a wireless transceiver module, and an MCU receives control signals from a remote terminal via the telephone connection to control the remote control module, by which the wireless transmission module is initiated to send out the corresponding wireless control signals. When an internet connection is established upon transmitting and receiving wireless internet signals by the wireless transceiver module, the MCU can download a control code set for an electronic device from a website via the internet connection, and the control code set is stored in a memory.
Applicant believes that another reference corresponds to U.S. Patent Application Publication No. 20070238481 (A1), published on Oct. 11, 2007 to Gaucherot for self-adhesive remote-control keyboard for a portable cellular telephone. However, it differs from the present invention because Gaucherot teaches a self-adhesive and sealed device having a deformable structure that enables, for example, a skier provided with a portable cellular telephone (a) connected to a transmission/reception interface (b) and to an earphone/microphone set (c) to transmit or receive telephone calls without taking off his gloves and without handling the portable telephone thereof. The keyboard is fixable to a support (a vehicle panel board, a motorcycle tank, clothes, on a flat part of ski) by means of an adhesive element ( 1 ) disposed on the lower face of a flexible pad ( 2 ). The pad is sealingly covered by an elastic shell ( 3 ), which comprises large keys ( 4 ) and a transparent window on the external face thereof. The sealed chamber, which is formed by the pad and shell, contains a battery, an electronic system for transmitting and receiving signals allocated to the interface of the portable telephone of a user and electric connections for said components. The anti-thief device of the keyboard is intrinsic in such a way that the keyboard is useless without the interface associated to the portable telephone.
Applicant believes that another reference corresponds to U.S. Patent Application Publication No. 20070232233 (A1), published on Oct. 4, 2007 to Liu, et al. for a wireless handset with “BLUETOOTH” remote control and dialing functionality on VoIP software application, and corresponding web phone. However, it differs from the present invention because Liu, et al. teach a wireless handset includes: a “BLUETOOTH” RF module for performing wireless communication with a Voice over Internet Protocol (VoIP) communication device having “BLUETOOTH” communication functionality; a processing circuit, coupled to the “BLUETOOTH” RF module, for remotely controlling a VoIP software application, which is embedded in the VoIP communication device, through the “BLUETOOTH” RF module according to “BLUETOOTH” Human Interface Device specifications; and an audio input/output module, coupled to the processing circuit, for receiving audio waves to input an audio signal into the processing circuit, and/or outputting audio waves; wherein the wireless handset provides web phone communication functionality by utilizing the VoIP software application.
Applicant believes that another reference corresponds to U.S. Patent Application Publication No. 20070035412 (A1), published on Feb. 15, 2007 to Dvorak, et al. for an application of profiles in a wireless device to control a remote control apparatus. However, it differs from the present invention because Dvorak, et al. teach a system ( 10 ) or method ( 50 ) for controlling a remote controlled apparatus that includes a remote controlled apparatus ( 18 ) and a remote controlling device ( 12 ). The remote controlling device can include a wireless transceiver ( 9 ) for controlling the remote controlled apparatus and a programmable memory ( 16 ) for storing profiles defining operation of the remote controlling device corresponding to the remote controlled apparatus. The wireless transceiver receives from the remote controlled apparatus data defining a profile or a selection signal for selecting among a plurality of stored profiles. The remote controlled apparatus can be an RC toy such as a car, boat or aircraft and the remote controlling device can be a phone or other transceiving device. The remote controlled apparatus can include a stored profile that can be modified using an exchangeable housing ( 26 , 28 or 44 ) having a predefined set of mechanisms for activating switches on the remote controlled apparatus.
Applicant believes that another reference corresponds to U.S. Patent Application Publication No. 20050192051 (A1), published on Sep. 1, 2005 to Tokuhashi for a mobile terminal-based remote control technique. However, it differs from the present invention because Tokuhashi teaches a remote control program installed in a cell phone that is activated to read a window number allocated to an operation window output and displayed on a TV receiver from a memory unit of the cell phone and to display corresponding help information on a display unit of the cell phone (steps S 100 and S 110 ). In response to the user's manipulation of one of buttons on an operation unit of the cell phone, the remote control program displays button function information representing the functions of the respective buttons on the operation unit, while converting an input signal into an operation signal and sending the converted operation signal together with the window number (steps S 120 to S 150 ).
Other patents describing the closest subject matter provide for a number of more or less complicated features that fail to solve the problem in an efficient and economical way. None of these patents suggest the novel features of the present invention.
SUMMARY OF THE INVENTION
The instant invention is a portable device shell. More specifically, the instant invention is a portable device shell, comprising an adapter assembly comprising a first cavity to snugly receive a portable electronic device and a control assembly comprising a second cavity to snugly receive the adapter assembly. The instant invention further comprises integrated electronics that act in concert when the adapter assembly snugly receives the portable electronic device and the control assembly snugly receives the adapter assembly. The control assembly further comprises an infrared emitter transmitter/receiver, radio frequency and/or a wireless medium to control and receive status from third party devices. The control assembly comprises a battery as a power source.
The portable electronic device is a hybrid mobile device, or having or serving as a phone and/or mobile communications platform, and comprises a first connector port and a screen. The adapter assembly comprises a first connector that inserts into the first connector port when the first cavity snugly receives the portable electronic device. The adapter assembly comprises a second connector port. The control assembly comprises a second connector that inserts into the second connector port when the second cavity snugly receives the adapter assembly.
The adapter assembly comprises an exterior top face, an exterior bottom face, and first and second exterior lateral faces. The adapter assembly further comprises an exterior front face and an exterior rear panel. The exterior bottom face comprises the second connector port, and the exterior front face comprises at least one control button. The adapter assembly further comprises an interior top face, an interior bottom face, first and second interior lateral faces, and an interior rear face.
The control assembly comprises an exterior top face, an exterior bottom face, and exterior first and second lateral faces. The control assembly further comprises an exterior front face and an exterior rear panel. The exterior front face comprises control buttons to operate functions including volume, navigation keys, and channel controls. The control assembly further comprises an interior top face, an interior bottom face, and first and second interior lateral faces, and together with a interior rear face, define the second cavity.
All the adapter assemblies are of a same size to fit within the second cavity. The control assembly further comprises an infrared emitter to directly control audiovisual equipment, thus allowing direct control of audiovisual gear through an embedded software application. An infrared emitter receiver can learn commands from other remote controls to learn infrared emitter commands and be able to transmit them through the infrared emitter to control equipment.
It is therefore one of the main objects of the present invention to provide a portable device shell that easily accommodates a portable electronic device to function as a control and gaming device.
It is another object of the present invention to provide a portable device shell that easily accommodates a portable electronic device for easier use and operation.
It is another object of the present invention to provide a portable device shell that is ergonomically designed.
It is another object of the present invention to provide a portable device shell that is lightweight.
It is another object of the present invention to provide a portable device shell that is volumetrically efficient for carrying, transporting, and storage.
It is another object of the present invention to provide a portable device shell that can be readily assembled and disassembled without the need of any special tools.
It is another object of the present invention to provide a portable device shell, which is of a durable and reliable construction.
It is yet another object of this invention to provide such a portable device shell that is inexpensive to manufacture and maintain while retaining its effectiveness.
Further objects of the invention will be brought out in the following part of the specification, wherein detailed description is for the purpose of fully disclosing the invention without placing limitations thereon.
BRIEF DESCRIPTION OF THE DRAWINGS
With the above and other related objects in view, the invention consists in the details of construction and combination of parts as will be more fully understood from the following description, when read in conjunction with the accompanying drawings in which:
FIG. 1 is a first isometric disassembled view of the present invention, and a portable electronic device.
FIG. 2 is a second isometric disassembled view of the present invention, and the portable electronic device.
FIG. 3 is an isometric assembled view of the present invention charging in a cradle with the portable electronic device.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings, the present invention is a portable device shell, and is generally referred to with numeral 10 . It can be observed that it basically includes adapter assembly 20 and control assembly 120 .
As seen in FIGS. 1 and 2 , portable electronic device 200 is a hybrid mobile device, and is further defined as any portable electronic device such as, but not limited to, products manufactured by Apple, Inc. such as “IPHONE”, “IPOD”, and “IPAD”, and others like “BLACKBERRY”, or “ANDROID” having or serving as a phone and/or portable media display device. Portable electronic device 200 has connector port 202 and screen 204 .
Adapter assembly 20 is designed to snugly receive portable electronic device 200 . Adapter assembly 20 comprises exterior top face 22 opposite from exterior bottom face 24 , and exterior lateral faces 26 and 28 . Adapter assembly 20 further comprises exterior front face 30 and exterior rear panel 32 . In a preferred embodiment, exterior bottom face 24 comprises connector port 34 , and exterior front face 30 comprises at least one control button 54 . Adapter assembly 20 further comprises interior top face 42 opposite from interior bottom face 44 , and interior lateral faces 46 and 48 that, together with interior rear face 50 define cavity 40 . In a preferred embodiment, interior bottom face 44 comprises connector 56 that inserts into connector port 202 .
Instant invention 10 may comprise a plurality of adapter assemblies 20 , each configured to receive various shapes of the various portable electronic devices 200 .
Control assembly 120 is designed to snugly receive adapter assembly 20 . Control assembly 120 comprises exterior top face 122 opposite from exterior bottom face 124 , and exterior lateral faces 126 and 128 . Control assembly 120 further comprises exterior front face 130 and exterior rear panel 132 . In a preferred embodiment, exterior front face 130 comprises control buttons 154 , 156 , and 158 . Control assembly 120 further comprises interior top face 142 opposite from interior bottom face 144 , and interior lateral faces 146 and 148 that, together with interior rear face 150 , define cavity 140 . In a preferred embodiment, interior bottom face 144 comprises connector 160 that inserts into connector port 34 . It is noted that all adapter assemblies 20 are of a same size to fit within cavity 140 of control assembly 120 .
Control assembly 120 provides a better grip, an extended battery, and more ergonomically accessible buttons when using portable electronic device 200 . As an example, control button 156 can be used to operate a function like volume. Control button 154 can be used to operate navigation keys, and control button 158 can be used to operate general functions such as channel controls. Control buttons 154 , 156 , and 158 are ergonomically positioned “hard” buttons, whereby functions like volume up/down, channel up/down, and navigation keys can be easily accessible. These buttons can be operated even though screen 204 of portable electronic device 200 is “off” to save battery life.
Screen 204 of portable electronic device 200 will still be used as a touch sensitive surface for ease of navigation.
Instant invention 10 further comprises the following hardware and features as an audiovisual electronics control. Control assembly 120 comprises infrared emitter 134 to directly control audiovisual equipment. This will allow instant invention 10 to directly control audiovisual gear through an embedded application. An infrared emitter receiver can learn commands from other remote controls, this will allow instant invention 10 to learn infrared emitter commands and be able to transmit them through infrared emitter 134 to control other equipment.
Control assembly 120 further comprises an infrared emitter transmitter/receiver, radio frequency, and/or a wireless medium such as “Z-WAVE” and/or “ZIGBEE” radio to control third party devices. This will allow instant invention 10 to control and receive status from other devices including, but not limited to, light dimmers/switches, air conditioner, and other compatible sensors.
Control assembly 120 allows for an extended battery, whereby it comprises built-in battery 162 .
Instant invention 10 can fit within an enclosure protected by a touch-sensitive, anti-glare surface, which at the same time could magnify an image for ease of operation. The surface could also be textured and “click” when pressed to provide a better tactile feel.
Furthermore, instant invention 10 may also serve as an automobile entertainment interface, whereby it will replace a vehicle's original equipment manufacturer radio and provide an easy connecting area for portable electronic device 200 .
Once connected to a vehicle's connector, not seen, instant invention 10 having portable electronic device 200 , allows to natively access Global Positioning System “GPS”, music, video, and other pertinent options. Instant invention 10 provides constant power as well as external antennas to portable electronic device 200 . External antennas could extend range to a cellular signal as well as the GPS. It could also include audio services not limited to AM, FM, HD, “XM”, and/or “SIRIUS” radio circuitry. When portable electronic device 200 is connected to instant invention 10 , and instant invention 10 is connected to the vehicle, it will gain access to these extra functions through connector port 202 and with the use of software. “BLUETOOTH” capability can also provide hands free operation. Furthermore, a user could access numerous Internet based entertainment streams presently not available in existing vehicle radios. In some instances, portable electronic device 200 with instant invention 10 will Internet access to any other WIFI based device in the vehicle with the use of a built-in wireless router in instant invention 10 .
Extra circuitry can be added to allow reception of audio services not limited to AM, FM, and HD radio terrestrial signals as well as “XM” and “SIRIUS” radio satellite programming. A custom application and interface handles tuning and radio reception features.
Instant invention 10 may also comprise a GPS antenna to improve range of the built-in GPS antenna, and a WIFI antenna and/or radio to better connect to an existing WIFI network. The built-in Internet connection of instant invention 10 can also be shared from within the vehicle to other computing devices like laptops and game consoles. This assumes that the service provider allows this type of “tethered” connection.
In the case of portable electronic devices 200 such as “IPHONE” and “IPOD TOUCH”, instant invention 10 synchronizes digital media and other information wirelessly when arriving at the user's home base where the media is stored. Instant invention 10 can stay “on” using the internal battery during the synchronization process. If the process takes longer than the battery allows, it could use the vehicle's battery. Instant invention 10 will turn off before draining the vehicle's battery.
Instant invention 10 may also comprise external microphone 164 and speaker 166 to allow it to serve as a hands-free phone, and a radio digital recorder to allow it to record (time shift) live radio broadcasts using a built-in storage capacity. Instant invention 10 can record prescheduled programming while the vehicle is not in use for later enjoyment. In this case, the user will be able to skip unwanted content as desired.
An ergonomic design is a critical aspect for instant invention 10 to physically optimize for current use.
As seen in FIG. 3 , control assembly 120 can also fit within cradle 180 for easy recharging.
The foregoing description conveys the best understanding of the objectives and advantages of the present invention. Different embodiments may be made of the inventive concept of this invention. It is to be understood that all matter disclosed herein is to be interpreted merely as illustrative, and not in a limiting sense.
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A portable device shell, comprising an adapter assembly comprising a first cavity to snugly receive a portable electronic device and a control assembly comprising a second cavity to snugly receive the adapter assembly. Integrated electronics act in concert when the adapter assembly snugly receives the portable electronic device and the control assembly snugly receives the adapter assembly. An infrared emitter transmitter/receiver, radio frequency and/or a wireless medium control and receive status from third party devices. The control assembly comprises a battery as a power source. The portable electronic device is a hybrid mobile device, or having or serving as a phone and/or mobile communications platform, and comprises a first connector port and a screen.
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RELATED APPLICATIONS
This application claims priority under 35 U.S.C. § 119(e) of the co-pending U.S. provisional application Ser. No. 60/101,853 filed on Sep. 25, 1998 and entitled “ALL-FIBER EDFA GAIN FLATTENING FILTER.” The provisional application Ser. No. 60/101,853 filed on Sep. 25, 1998 and entitled “ALL-FIBER EDFA GAIN FLATTENING FILTER” is also hereby incorporated by reference.
FIELD OF THE INVENTION
The present invention relates to the field of fiber optic communications. More particularly, the present invention relates to the field of filtering of amplified signals used in fiber optic communications systems.
BACKGROUND OF THE INVENTION
Fiber optic communication systems use optical fibers to carry a modulated lightwave signal between a transmitter and a receiver. A cross-section of a typical optical fiber is illustrated in FIG. 1 . The optical fiber 2 includes a core 4 and a cladding 6 . Optionally, the optical fiber 2 includes a jacket 8 . In a typical optical fiber, the core 4 has an index of refraction greater than the cladding 6 , thereby forming an optical waveguide. By maintaining the core diameter within an allowed range, light traveling within the core 4 is limited to a single mode. If included, the jacket 8 protects the outer surface of the cladding 6 and absorbs stray light traveling within the cladding 6 . A typical single mode optical fiber intended for use in communication systems operating at a 1300 nm wavelength band or a 1550 nm wavelength band has a core diameter of about 8 μm and a cladding outside diameter of 125 μm. If the jacket 8 is included, the jacket 8 typically has an outside diameter of 250 μm.
In Wavelength Division Multiplexing (WDM) systems, multiple signals are carried by various wavelengths of light through a single optical fiber. A typical WDM system is shown in FIG. 2 . The WDM system 10 includes a transmission system 11 , which includes a series of transmitters 12 , 14 , and 16 , each coupled to a multiplexer 18 . The multiplexer 18 provides an output, which is coupled to an optical fiber 20 . Over long distances amplifiers 22 are included along the optical fiber 20 . The optical fiber 20 is then also coupled to a receiving system 23 , which includes a demultiplexer 24 and a series of receivers 26 , 28 , and 30 . The optical fiber 20 is coupled to an input of the demultiplexer 24 of the receiving system 23 . Outputs of the demultiplexer 24 are coupled to the series of receivers 26 , 28 , and 30 .
In the WDM system 10 , a first transmitter 12 transmits a light signal at a first wavelength (λ 1 ), a second transmitter 14 transmits a light signal at a second wavelength (λ 2 ) and so forth until an nth transmitter 16 transmits a light signal at an nth wavelength (λ n ) The shortest wavelength signal and the longest wavelength signal form a wavelength band. The signals are combined by the multiplexer 18 , which then transmits the light signals along the optical fiber 20 . Over distance the power of the light signals decrease due to attenuation. The light signals are typically amplified about every 50-100 km. For the 1550 nm wavelength band, this amplification is generally performed by an Erbium Doped Fiber Amplifier (EDFA) 22 . When the light signals reach their destination they are separated by the demultiplexer 24 . The light signals are then received by the receivers 26 , 28 , and 30 . Light signal intensity versus wavelength for a typical wavelength band of WDM light signals is illustrated in FIG.
Flat gain response for EDFAs is crucial to the performance of the WDM system 10 , since small variations in gain for various wavelengths will grow exponentially over a series of in-line EDFAs 22 . Agrawal in “Fiber Optic Communication Systems,” (Wiley. 2nd ed., 1997. pp 414-415) teaches that numerous methods can be used to flatten the gain response of these amplifiers. One method of flattening this gain response is to use channel filters to equalize the gain for various wavelengths. Another method is to adjust the input powers of different wavelengths so that amplification results in uniform intensity for various wavelengths. A third method is to use inhomogeneous broadening of the EDFA gain spectrum to equalize wavelength intensity. A fourth method is to use multiple EDFAs tuned to different wavelength ranges and configured with feedback loops. A final method is to use a filter or series of filters to selectively attenuate the gain response of an EDFA.
A typical gain versus wavelength response for an EDFA is shown in FIG. 4 A. When utilizing a filter or series of filters to flatten gain response, an optical filter, with an attenuation curve as shown in FIG. 4B, can be used to selectively attenuate the gain response. The resulting attenuated EDFA gain is shown in FIG. 4 C. As shown in FIG. 4C, this attenuated EDFA gain is substantially flat over a range of wavelengths including 1530 nm to 1560 nm. Without a substantially flat gain the quality of the signal received by the receivers 26 , 28 , and 30 will be poor.
There are many different known methods for selectively attenuating the gain response of an EDFA in order to improve the signal quality of the signals received by the receivers 26 , 28 , and 30 . U.S. Pat. No. 5,260,823 to Payne et al. entitled, “Erbium-Doped Fibre Amplifier with Shaped Spectral Gain,” teaches that a wavelength-selective resonant coupling between a propagating core mode to a cladding leaky mode can be used for filtering a wavelength band for EDFA A gain flattening. A periodic perturbation of the core forms a grating and the selected wavelength is attenuated by the resonant coupling between the core and the cladding. By varying the perturbation length, various selected wavelengths can be attenuated. Payne et al. also teach that multilayered dielectric coatings can be used for making an optical filter for EDFA gain flattening. A multilayered filtering apparatus includes two coupling lenses and a multilayered dielectric filter. The two coupling lenses connect to an optical fiber and sandwich the multilayered dielectric filter. The multilayered dielectric filter is designed to cancel out the larger gain around the peak wavelength and to be transparent elsewhere.
U.S. Pat. No. 5,473,714 to Vengsarkar entitled, “Optical Fiber System Using Tapered Fiber Devices,” teaches that tapered fiber devices can be used for filtering in an optical telecommunications system. Vengsarkar teaches that by tapering an optical fiber, light can be attenuated by wavelength cutoff and direct coupling from a core to a cladding. The tapered fiber device is formed from the optical fiber by heating the optical fiber and stretching it. The taper reduces the diameter of the core to a value close to the cutoff wavelength. Light with wavelengths near and above the cutoff wavelength are coupled directly to the cladding.
U.S. Pat. No. 5,583,689 to Cassidy et al. entitled “Filter With Preselected Attenuation/Wavelength Characteristic,” teaches that a fiber grating, with spatially separated parts having different attenuation characteristics, can perform filtering for EDFA gain flattening. The fiber grating is preferably a side-tap Bragg fiber grating. By varying the pitch along the fiber grating an appropriate attenuation profile can be provided for flattening the EDFA gain response.
U.S. Pat. No. 5,067,789 to hall et al. entitled, “Fiber Optical Coupling Filter and Amplifier,” teaches that a light-attenuating light path adjacent to a first core within a cladding can be used to filter wavelengths about a specific wavelength for EDFA gain flattening. The light attenuating light path is preferably one or more lossy cores that are evanescently coupled to the first core. The evanescent coupling between the first core and the light attenuating light path is greatest where the effective index of refraction of the first core equals the effective index of refraction of the light attenuating light path. By choosing a single mode or a higher multimode optical waveguide structure for the light attenuating light path, the effective index of refraction for the light attenuating light path can be varied. Hall et al. teach that the index of refraction for the material for the light attenuating light path should be greater than the index of refraction for the material for the first core. Hall et al. further teach that as an alternative embodiment the lossy core could be a lossy annular region located concentrically about the first core and within the cladding. A necessary feature of this filter is that the lossy core or the lossy annular region has specific light absorption characteristics. Since the lossy core or the lossy annular region is contained completely within the cladding, the specific light absorption characteristics dissipates light energy that has been filtered from the first core to the lossy core or the lossy annular region. The absorption characteristics of the lossy core or the lossy annular region determine an amount of attenuation of the filtered wavelengths.
Each of these known methods for filtering an amplified signal from an EDFA can be inefficient, unreliable, and expensive. There is currently a lack of efficient filters for gain flattening in fiber optic systems, which are easy to manufacture and use within a WDM system.
SUMMARY OF THE INVENTION
An all fiber optical filter is formed by stretching an optical fiber. The all fiber filter includes a core, an inner cladding, and an outer cladding. A core index of refraction is greater than an outer cladding index of refraction. The outer cladding index of refraction is greater than an inner cladding index of refraction. The all fiber optical filter attenuates a portion of an optical signal by transferring optical energy from the core to the outer cladding by evanescent coupling. The all fiber optical filter has a compact structure, which prevents bending and provides stable temperature performance.
The all fiber optical filter is preferably used in Wavelength Division Multiplexing (WDM) systems for gain flattening of gain responses from Erbium Doped Fiber Amplifiers (EDFAs). Alternatively, the all fiber optical filter is used in other applications where optical filtering or attenuation is needed.
The all fiber optical filter is manufactured by holding a length of an appropriate optical fiber between two clamps, heating the optical fiber, and stretching the optical fiber until a predetermined characteristic of the optical fiber is achieved.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates a cross section of an optical fiber of the prior art.
FIG. 2 illustrates a block diagram of a WDM system of the prior art.
FIG. 3 illustrates a graph of intensity versus wavelength for a wavelength band of WDM light signals of the prior art.
FIG. 4A illustrates an EDFA gain curve over a range of wavelengths of the prior art.
FIG. 4B illustrates a filter attenuation curve over a range of wavelengths for gain band flattening of the prior art.
FIG. 4C illustrates an attenuated EDFA gain curve over a range of wavelengths using a filter of the prior art.
FIG. 5 illustrates a linear cross section of an all fiber optical filter of the present invention.
FIG. 6 illustrates a cross-section of the all fiber optical filter of the present invention.
FIG. 7 illustrates the all fiber optical filter and additional structure of the present invention.
FIGS. 8A, 8 B, and 8 C illustrate configurations including an EDFA, a first all fiber optical filter, and a second all fiber optical filter of the present invention.
FIGS. 9A and 9B illustrate intensity versus wavelength for an EDFA gain response and a filtered EDFA gain response of the present invention.
FIG. 10 illustrates an EDFA and an all fiber optical filter of the present invention.
FIG. 11 illustrates a WDM system including the all fiber optical filter of the present invention.
FIG. 12 illustrates a first apparatus for making the all fiber optical filter of the present invention.
FIG. 13 illustrates a second apparatus for making the all fiber optical filter of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
A linear cross section of an all fiber optical filter of the present invention is illustrated in FIG. 5 . The all fiber optical filter 32 has a core 34 , an inner cladding 36 , an outer cladding 38 , and a filter length 40 . A cross-section of the all fiber optical filter 32 showing the core 34 , the inner cladding 36 , and the outer cladding 38 is illustrated in FIG. 6 . The core 34 has a core diameter. The inner cladding 36 has an inner cladding thickness. The outer cladding 38 has an outside diameter. Indexes of refraction for the core 34 , the inner cladding 36 , and the outer cladding 38 are referred to as a core index of refraction, an inner index of refraction, and an outer index of refraction, respectively. The core index of refraction is preferably greater than the outer index of refraction. The outer index of refraction is preferably greater than the inner index of refraction. By an appropriate selection of the core index of refraction, the inner index of refraction, and the outer index of refraction as well as selecting, the core diameter and the inner cladding thickness, optical energy from an optical signal within a wavelength range is transferred from the core 34 to the outer cladding 38 by evanescent coupling.
The core 34 of the all fiber optical filter 32 is a single mode waveguide. A convention used when discussing optical waveguides is to refer to an effective index of refraction, which is defined as a waveguide propagation constant β divided by a free space wave number k o . The effective index of refraction is both wavelength dependent and mode dependent. A core effective index of refraction for the core 34 has a value between the inner index of refraction and the core index of refraction. Reducing the core diameter reduces the core effective index of refraction provided that the single mode continues to propagate. The outer cladding 38 is a multimode waveguide. The outer cladding is sufficiently large that an outer effective index of refraction for a first mode is equal to the outer index of refraction. The inner cladding 36 forms a barrier between the core 34 and the outer cladding 38 . Optical energy will transfer from the core 34 to the cladding 38 by evanescent coupling if the core effective index of refraction is near to the outer index of refraction and the barrier is sufficiently narrow. Since the core effective index of refraction depends upon the core diameter, the core diameter determines a wavelength range that could couple from the core 34 to the outer cladding 38 .
The core diameter, the core effective index of refraction, and the outer index of refraction determine a peak attenuation wavelength and a wavelength band about the peak attenuation wavelength that couples from the core 34 to the outer cladding 38 . Optical energy that couples from the core 34 to the outer cladding 38 and is propagating in the first mode can couple back to the core 34 . Accordingly, the outer diameter of the outer cladding and the filter length 40 adjust the peak attenuation wavelength and the wavelength band about the peak wavelength. Depending upon a variation of the core effective index of refraction with wavelength, other peak attenuation wavelengths and wavelength bands could couple from the core 34 to the outer cladding 38 .
The all fiber optical filter 32 and additional structure is illustrated in FIG. 7 . The additional structure includes an input length 42 , an output length 44 , a first transition 46 , and a second transition 48 . The input length 42 connects to the first transition 46 , which connects to the all fiber optical filter 32 . The all fiber optical filter 32 connects to the second transition 48 , which connects to the output length 44 . The core 34 , the inner cladding 36 , and the outer cladding 38 of the all fiber optical filter 32 extend through the input length 42 , the first transition 46 , the second transition 48 , and the output length 44 . The thickness of the inner cladding 36 , within the input length 42 and the output length 44 , is greater than an evanescent coupling thickness that allows evanescent coupling between the core 34 and the outer cladding 38 within the input length 42 and the output length 44 . The input length 42 and the output length 44 are coupled to an optical fiber system by appropriate means available for coupling optical fiber components.
An exemplary configuration including an EDFA and a cascaded series of all fiber optical filters used to flatten the EDFA gain over wavelength ranges of 1529 nm to 1562 nm and 1580 nm to 1620 mn is illustrated in FIG. 8 A. The EDFA 52 is coupled to a first all fiber optical filter 54 . The first all fiber optical filter 54 is coupled to a second all fiber optical filter 56 . An input optical signal 58 is provided to the EDFA 52 , which amplifies the input optical signal 58 and provides an amplified optical signal. The amplified optical signal is then provided to the first all fiber optical filter 54 , which filters the amplified optical signal and provides a first filtered optical signal. The first filtered optical signal is then provided to the second all fiber optical filter 56 , which filters the first filtered optical signal and provides an output optical signal 60 .
Other configurations for the EDFA 52 , first all fiber optical filter 54 , and the second all fiber optical filter 56 are illustrated in FIGS. 8B and 8C. In FIG. 8B, the first all fiber optical filter 54 is coupled to the EDFA 52 , which is coupled to the second all fiber optical filter 56 . In FIG. 8C, the first all fiber optical filter 54 is coupled to the second all fiber optical filter, which is coupled to the EDFA 52 .
In the preferred embodiment of the present invention, intended to operate in the wavelength ranges of 1529 nm to 1562 mn and 1580 nm to 1620 nm, the core 34 , the inner cladding 36 , and the outer cladding 38 are silica glasses. The indexes of refraction are preferably 1.467 for the core index of refraction, 1.411 for the inner index of refraction, and 1.424 for the outer index of refraction. The core diameter is preferably within the range and including 3 μm and 6 μm. An outer diameter for the inner cladding 36 is preferably within the range and including 12 μm and 30 μm. The outside diameter of the outer cladding 38 is preferably within the range and including 50 μm and 85 μm. The filter length 40 is preferably within the range and including 10 mm and 20 mm. Specific dimensions for the preferred embodiment are a result of a forming process, which preferably uses an optical spectrum response for the all fiber optical filter 32 as a critical parameter.
The preferred embodiment for the all fiber optical filter 32 is formed by identifying a preferred peak EDFA gain response and a preferred wavelength band about the preferred peak gain response that is to be flattened. An inverse of the gain response for the preferred wavelength band becomes a preferred target response for the all fiber optical filter 32 such that the all fiber optical filter 32 provides a preferred attenuation response that is near to the preferred target response after the forming process.
Referring to FIG. 8A, the EDFA 52 provides the amplified optical signal, which is used to determine the first peak EDFA gain response and the first wavelength band. For a test EDFA used in testing an all fiber optical filter of the present invention, the preferred peak EDFA gain response was found to be at 1533 nm with a preferred relative gain response of 6.0 dB. The relative gain response is defined as the difference between a specific gain response for a specific wavelength and a minimum gain response for the wavelength range. The preferred target response about 1533 nm was used in the forming process so that after the forming process, the all fiber optical filter 32 provided the preferred attenuation curve.
An alternative embodiment is formed by identifying an alternate target response for an alternate peak EDFA gain response and an alternate wavelength band about the alternate peak EDFA gain response. For the test EDFA, the alternate peak wavelength was found to be at 1552 nm with an alternate relative gain response of 3.83 dB.
Referring to FIG. 8A, tests were performed in which the EDFA 52 was the test EDFA, the first all fiber optical filter 54 was the preferred embodiment of the all fiber optical filter described above and having the preferred attenuation response, and the second all fiber optical filter 56 was the alternative embodiment of the all fiber optical filter described above and having an alternate attenuation response. Test results using this configuration for the wavelength range from 1529 nm to 1562 nm are illustrated in FIG. 9 A. The EDFA gain response is shown as the curve A. The first target response is the inverse of the EDFA gain response from 1529 nm to 1540 nm. The second target response is the inverse of the EDFA gain response from 1540 nm to 1562 nm. The output optical signal 60 is shown as the curve B, which shows a substantially flat attenuated EDFA gain curve over the wavelength range from 1529 nm to 1562 nm.
Test results using this configuration for the wavelength range from 1580 nm to 1620 are illustrated in FIG. 9 B. The EDFA gain response is shown as the curve C. The output optical signal 60 is shown as the curve D, which shows a substantially flat attenuated gain curve over the wavelength range from 1580 nm to 1620 nm.
An alternative embodiment comprising the EDFA 52 and a single all fiber optical filter is illustrated in FIG. 10 . Depending upon the gain response of the EDFA 52 the single all fiber optical filter 62 will suffice to flatten the gain response of the EDFA 52 . The EDFA 52 is coupled to the single all fiber optical filter 62 . The input optical signal 58 is provided to the EDFA 52 , which amplifies the input optical signal 58 and provides an amplified optical signal. The amplified optical signal is then provided to the single all fiber optical filter 62 , which filters the amplified optical signal and provides the output optical signal 60 .
A WDM system with EDFA gain flattening including one or more all fiber optical filters according to the present invention is illustrated in FIG. 11 . The WDM system 66 includes a transmission system 11 , which includes a series of transmitters 12 , 14 , and 16 each coupled to a multiplexer 18 . The multiplexer 18 provides an output, which is coupled to an optical fiber 20 . Over long distances EDFAs 22 and the one or more all fiber optical filters 68 are included along the optical fiber 20 . The optical fiber 20 is then also coupled to a receiving system 23 , which includes a demultiplexer 24 and a series of receivers 26 , 28 , and 30 . The optical fiber 20 is coupled to an input of the demultiplexer 24 of the receiving system 23 . Outputs of the demultiplexer 24 are coupled to the series of receivers 26 , 28 , and 30 .
In the WDM system 66 , a first transmitter 12 transmits a light signal at a first wavelength (λ 1 ), a second transmitter 14 transmits a light signal at a second wavelength (λ 2 ), and so forth until an nth transmitter 16 transmits a light signal at an nth wavelength (λ n ). The light signals are combined by the multiplexer 18 , which then transmits the light signals along the optical fiber 20 . Over distance the power of the light signals decrease due to attenuation. The light signals are amplified approximately every 50-100 km by the EDFAs 22 , the one or more all fiber optical filters 68 flatten the EDFA gain for the light signals, as discussed above. When the light signals reach their destination they are separated by the demultiplexer 24 . The light signals are then received by the receivers 26 , 28 , and 30 .
A first apparatus for manufacturing the all fiber optical filter of the present invention is illustrated in FIG. 12 . The first apparatus 70 includes a heating source 72 , a first clamp 74 , a second clamp 76 , a first stepper motor 78 , a second stepper motor 79 , a first drive means 80 , and a second drive means 81 . The first clamp 74 is placed to one side of the heating source 72 . The second clamp 76 is placed adjacent to the heating source 72 on the side opposite to the first clamp 74 . The first clamp 74 is connected to the first stepper motor 78 by the first drive means 80 . The second clamp 76 is connected to the second stepper motor 79 by the second drive means 81 .
A first method of manufacture uses the first apparatus 70 . An initial length of optical fiber 82 is held between the first clamp 74 and the second clamp 76 . The heating source 72 heats the optical fiber 82 to within an allowed temperature range. The first stepper motor 78 actuates the first drive means 80 . The second stepper motor 79 actuates the second drive means 81 . Consequently, the first clamp 74 and the second clamp 76 are further separated. This further separation stretches the optical fiber 82 . When a predetermined stretch distance has been reached the first and second stepper motor 78 and 79 are stopped, which stops the first and second clamp 74 and 76 . Finally, the heating source 72 is removed, the heating source 72 is turned off, or the optical fiber 82 is removed from the heating source 72 . This results in an all fiber optical filter, according to the present invention, having a predetermined filter length.
A second and preferred apparatus for manufacturing the all fiber optical filter of the present invention is illustrated in FIG. 13 . The second apparatus 84 includes the first apparatus 70 , a process control unit 86 , a light source 88 , and an optical spectrum analyzer 90 . The light source 88 is located at one end of the optical fiber 82 . The optical spectrum analyzer 90 is located at the end of the optical fiber 82 opposite to the light source 88 . The process control unit 86 controls and monitors the heating source 72 through a first control link 92 . The process control unit 86 controls the first stepper motor 78 through a second control link 94 . The process control unit 86 controls the second stepper motor 79 through a third control link 95 . The process control unit 86 controls the light source 88 through a fourth control link 96 . Tile process control unit 86 controls and monitors the optical spectrum analyzer 90 through a fifth control link 98 .
A second and preferred method of manufacture uses the second apparatus 84 . The initial length of optical fiber 82 is held between the first clamp 74 and the second clamp 76 . The process control unit 86 signals and monitors the heating source 72 . The heating source 72 heats the optical fiber to within the allowed temperature range. The process control unit 86 turns on the light source 88 . The light source 88 couples light to the optical fiber 82 . Preferably, the light source 88 is a white light source. The optical fiber 82 transmits the light to the end of the optical fiber 82 opposite the light source 88 . The light exits the optical fiber 82 . The process control unit turns on the optical spectrum analyzer 90 . The optical spectrum analyzer 90 detects the light that exits from the optical fiber 82 . The process control unit 86 signals the first and second stepper motors 78 and 79 . The first and second stepper motors 78 and 79 further separate the first and second clamps 74 and 76 . This further separation stretches the optical fiber 82 . As the optical fiber 82 is stretched, the light signal at the end of the optical fiber adjacent to the optical spectrum is monitored for a predetermined optical spectrum response that is based on the target response, as described above. When the optical spectrum analyzer 90 detects the predetermined optical spectrum response, the process control unit 86 stops the first and second stepper motors 78 and 79 , thereby stopping the first and second clamp 74 and 76 . Finally, the process control unit signals the heating source 72 to stop heating. This results in an all fiber optical filter, according to the present invention, having a desired attenuation response.
Preferably, the optical fiber 82 used to form the all fiber optical filter 32 of the present invention has a core with an initial diameter of 8.3 μm, an inner cladding with an initial outside diameter of 45 μm, and an outer cladding with an initial outside diameter of 125 μm. Preferably, a length of 6 mm is heated by the heating source 72 to a temperature within the range between 900° C. and 1100° C. The optical fiber 82 is stretched to a length of about 15 mm. Preferably, the specific stretch length and other dimensions of the all fiber optical filter are determined by the predetermined optical spectrum response.
It will be readily apparent to one skilled in the art that other various modifications may be made to the preferred embodiment without departing from the spirit and scope of the invention as defined by the appended claims. Specifically, the all fiber optical filter of the present invention could be used to flatten the gain of other rare earth doped fiber amplifiers or the all fiber optical filter of the present invention could be used to filter or attenuate any optical signal.
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An all fiber optical filter is formed by stretching an optical fiber. The all fiber filter includes a core, an inner cladding and an outer cladding. A core index of refraction is greater than an outer cladding index of refraction. The outer cladding index of refraction is greater than an inner cladding index of refraction. The all fiber optical filter attenuates a portion of an optical signal by transferring optical energy from the core to the outer cladding by evanescent coupling. The all fiber optical filter has a compact structure, which prevents bending and provides stable temperature performance. The all fiber optical filter is preferably used in Wavelength Division Multiplexing (WDM) systems for gain flattening of gain responses from Erbium Doped Fiber Amplifiers (EDFAs). Alternatively, the all fiber optical filter is used in other applications where optical filtering or attenuation is needed. The all fiber optical filter is manufactured by holding a length of an appropriate optical fiber between two clamps, heating the optical fiber, and stretching the optical fiber until a predetermined characteristic of the all fiber optical filter is achieved.
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FIELD OF THE INVENTION
The present invention relates generally to the field of communications and particularly to portable radiotelephones coupled to vehicular adapters.
BACKGROUND OF THE INVENTION
Portable cellular radiotelephones, a typical block diagram of which is illustrated in FIG. 3, have become a popular and convenient means of communication while away from a landline telephone. A radiotelephone user can communicate to other parties around the world while remaining mobile. A limitation of portable radiotelephones, however, is the reduced power and antenna gain compared to mobile radiotelephones.
To overcome these limitations, power boosters or antenna extenders have been mounted in automobiles to connect to the portable. A power booster increases a portable's typical 600 mW power to the power level of a mobile, 3 W. An antenna extender simply couples a portable's antenna to a higher gain antenna mounted on the exterior of the vehicle, thus providing better communications for the portable. The communication system formed by the connection of the portable to the booster or antenna extender uses the memory and functions of the portable while the transmit power from the portable is amplified to the cellular system limit.
The drawback with the power booster/antenna extender in combination with the portable is that the portable must be connected to the system in order to operate. The portability that makes the portable radiotelephone an asset reduces the likelihood that the radiotelephone user will remember to connect the portable to the booster/extender. The user may take the phone into the home or office and forget to connect it to the mobile system until having driven a considerable distance. There is a resulting need to alert the driver that the portable is not present in the booster/extender system.
SUMMARY OF THE INVENTION
The method of the present invention encompasses generating an alert in response to a communication device being absent from a communication system. The communication device has a system connection. The method first determines if the system connection is connected to the communication system. If the system connection is connected, the communication device is activated. If the system connection is not connected, an alert is generated.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a flowchart of the process of the present invention.
FIG. 2 shows a block diagram of a radiotelephone and power booster/antenna extender system having an alert generation capability.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The process of the present invention prevents a radiotelephone user from forgetting to connect a portable radiotelephone to a mobile power booster/antenna extender. This gives the radiotelephone user the opportunity to connect the radiotelephone before driving off and leaving it at the home or office. For the purposes of this discussion, the radiotelephone will subsequently be assumed to be coupled to a power booster and is illustrated in FIG. 2.
The radiotelephone (200) is comprised of a transmitter (201), receiver (202), and a logic unit (203) that controls the radiotelephone (200). On power-up, the logic unit (203) generates a dte signal that informs the power booster that the radiotelephone is connected.
The radiotelephone power booster (220) is comprised of a receiver (221), a transmitter (222) able to operate at higher power levels, a logic unit (223) to control the booster (220), memory (225) to store telephone numbers and digitized voice messages, and a voice synthesizer circuit (224). A speaker (226) provides an output for the voice synthesizer circuit (224) as well as acting as a hands-free speaker for the radiotelephone (200). The process of the present invention is used by the logic unit (223) of the power booster (220).
Power (230) and a ground connection (231) is provided from the vehicle. An ignition line (232) from the vehicle's ignition system enables the power booster (220) to sense when the ignition has been enabled. The presence of the ignition signal (232) enables power to the communications system (200 and 220); the radiotelephone (200) receiving power through its interconnect to the power booster (220). At power-up, the booster logic unit (223) looks for a dte message from the portable's logic unit (203) that is sent during the portable's power-up sequence.
Referring to FIG. 1, the process of the present invention is initiated by the vehicle ignition being turned on (101). If the dte signal is detected by the booster's logic unit (102), the portable is present. No alert is activated from the booster logic unit to the voice chip and power is applied to the portable (103).
If the dte signal is not detected, the portable is not connected or is not operating properly. In this case, the process waits a short time (110), 10 seconds in the preferred embodiment, then generates an alert to warn the user that the portable must be installed (104). In the preferred embodiment, this alert is in the form of a voice message. An example of such a message is: "Portable missing, cellular telephone not available".
After the initial alert, the user has another chance to connect the portable radiotelephone to the power booster. In the preferred embodiment, the system waits 1 minute. During this time, the system checks for the dte message again to determine if the portable has been connected (105). If the portable has been connected (106), power is applied and the alert is not used. If the dte signal has still not been received, the portable has not been connected, the process waits (111) and then the alert message is repeated once more (107). This last delay is 5 seconds in the preferred embodiment. It is then assumed that the user does not want the portable connected. This process will not repeat until the automobile's ignition has been turned off and back on again.
Alternate embodiments of the process of the present invention can use other voice messages or alert tones to signal the absence of the portable. Additionally, alternate embodiments may delay a different length of time before generating the alert. An additional delay can also be used in after the first alert to allow time for the radiotelephone to be connected to the power booster.
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The process of the present invention alerts a radiotelephone user when the portable is not connected to the power booster/antenna extender system. By checking for a connect signal from the radiotelephone, the system knows the portable is missing and alerts the user, thus enabling the user to install the portable before driving off without it.
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CROSS-REFERENCE TO RELATED APPLICATION
This application is a continuation-in-part of my prior patent application Ser. No. 621,647filed Oct. 14, 1975, now abandoned and entitled FORM TIE.
BACKGROUND OF THE INVENTION
This invention relates to forms for concrete and the like and more particularly to an improved unitary article of manufacture for use in assembling such forms in the field.
In constructing walls, foundations, curbs and the like of concrete or similar initially fluid materials which subsequently harden into the desired structure, it is common to fabricate a form consisting of spaced sides or panels defining the exterior side surfaces of the desired structure. It has been proposed in the prior art to provide elongated metal members or form ties adapted to extend between the sides or panels of a form and temporarily tie the sides or panels of the form to each other while concrete, for example, is poured into the form and allowed to harden. Such form ties are thus embedded in the concrete and means are provided for the subsequent release of the form sides from the form ties so that the form sides or panels may be removed for reuse.
U.S. Pat. Nos. 1,097,796 (Fuehrer) and 1,729,807 (Toogood) are representative of prior art form ties. However, the form tie disclosed by Fuehrer will not resist either shear forces or transverse forces acting on the form sides unless used in pairs at given locations to form an X-shape configuration. The form tie disclosed by Toogood will resist transverse forces acting on the form sides when used alone at a given location but will not resist shear forces even if more than one is used at a given location.
It is an object of this invention to provide a unitary form tie which will resist both shear and transverse forces acting on the form sides at a given location when used by itself at such given location.
U.S. Pat. No. 3,199,827 (Terry) discloses a preassembled multi-element form tie which includes a pair of elements similar to the form tie described by Toogood interconnected by additional elements adapted to resist vertical shear forces. However, the form tie disclosed by Terry is not as effective as a pair of form ties as disclosed by Fuehrer of comparable size in resisting vertical shear forces even though it is more complicated in structure.
It is an object of this invention to provide a unitary form tie which will provide resistance to vertical shear forces acting on the form sides at a given location approaching maximum for its size when used by itself at such given location.
It will be noted that none of the form ties of the prior art provide resistance to horizontal shear forces acting on the form sides.
It is an object of this invention to provide a unitary form tie which may be oriented to resist horizontal shear forces acting on the form sides in addition to resisting vertical shear forces and transverse forces acting on the form sides.
SUMMARY OF THE INVENTION
According to this invention, a pair of form sides are fixed in selected spaced position with respect to each other against shear and transverse forces acting on such pair of form sides at a given location by means of a form tie comprising a unitary elongated metal member of generally Z-shape configuration. Thus, according to this invention, the form tie has generally parallel end portions joined by an intermediate diagonal portion with the free end of each end portion having a bight formed therein terminating in a rectilinear tab extending transversely of the end portion. The other end of each end portion has a bight formed therein and a rectilinear brace portion interposed between the bight and the intermediate diagonal portion of the member. Such interposed rectilinear brace portions extend substantially normal to the generally parallel end portions of the Z-shaped metal member.
BRIEF DESCRIPTION OF THE DRAWING
The foregoing and other objects and features of the subject invention will be more fully understood from a reading of the following detailed description of preferred embodiments thereof in conjunction with the attached drawing wherein:
FIG. 1 is an exploded perspective view showing a pair of form sides and their interconnection by means of two form ties in two different positions according to the teaching of this invention.
FIG. 2 is a top plan view of the form sides and form ties of FIG. 1 as fully assembled.
FIG. 3 is a cross-sectional view taken along line 3--3 of FIG. 2.
FIG. 4 is a cross-sectional view similar to FIG. 3 but showing a further embodiment of this invention.
FIG. 5 is an enlarged cross-sectional view taken along line 5--5 of FIG. 2.
DESCRIPTION OF PREFERRED EMBODIMENTS
Referring to FIG. 1, the teaching of this invention is shown as applied to the fabrication of forms for use in constructing walls, foundations, curbs and the like of concrete, for example. It is common in the prior art to fabricate forms for concrete of plywood panels 10 as shown in exploded view in FIG. 1. Thus, each of the panels 10 is provided with a plurality of holes therethrough in spaced array which may be aligned with the spaced array of holes in the other panel to receive therethrough the ends of a prefabricated form tie structure as disclosed in U.S. Pat. No. 3,199,827 mentioned hereinabove. In accordance with the teaching of the prior art, the ends of the prefabricated form tie structure may include bight portions terminating in transverse tabs and adapted to extend through the holes 12 a sufficient distance to receive wedges 14 by means of which the panels may be removably affixed to the prefabricated form tie structures.
In accordance with the teaching both of the prior art and this application, the panels 10 are assembled in fixed spaced relation with respect to each other as indicated by dotted lines in FIG. 1 by means of form ties and concrete or the like is introduced therebetween. After the concrete or the like has hardened, the form ties will be embedded therein but the panels 10 may be removed for reuse by removing the wedges 14 to free the panels 10 from the form ties. The prefabricated form tie structures of the prior art have been complicated in their structure and assembly and have tended to require an excess of material in order to provide adequate resistance to transverse forces acting on the panels 10 and tending to move the panels 10 toward or away from each other. However, the prefabricated form tie structures of the prior art have been deficient in providing resistance to shear forces acting on the panels 10 and tending to move the panels 10 in the planes of their major surfaces.
According to the teaching of this invention, form ties 20,21 comprising a simple unitary prefabricated elongated metal member is provided. Such form ties 20,21 provide a resistance to both transverse forces and shear forces acting on the panels at the location of the tie which approaches maximum for the amount of material used in the form tie.
Thus it will be seen that the form ties 20,21 according to the teaching of this invention comprise an elongated metal member such as heavy gauge wire formed into a generally Z-shape configuration. Thus the form tie 20,21 includes generally parallel end portions 22, 24 interconnected by an intermediate diagonal portion 23,23' . The only difference between the form ties 20 and 21 is that the diagonal portion 23' of the form tie 21 is longer than the diagonal portion 23 of the form tie 20.
Thus, as shown in FIGS. 1 and 2 of the drawing, the form tie 20 is adapted to be positioned vertically between the panels 10 for interconnection therewith whereas the form tie 21 is adapted to be positioned at an angle to the vertical between the panel members 10 for interconnection therewith. As will be more fully described hereinafter, a form tie structure in accordance with the teaching of this invention when in the position of the form tie 20 will resist vertical shear forces exerted on the panels 10 in addition to resisting transverse forces tending to move the panels 10 toward or away from each other. Similarly, as will be more fully described hereinafter, a form tie in accordance with the teaching of this invention in the position of form tie 21 will resist both vertical and horizontal shear forces exerted on the panels 10 in addition to resisting transverse forces tending to move the panel members 10 toward and away from each other.
As best shown in FIGS. 2 and 3, the free ends of the end portions 22 and 24 of the form ties 20,21 each have a bight 25 formed therein which terminates in a tab 26 extending transversely of the end portion 22,24. Similarly, the other end of each end portion 22,24 of the form ties 20,21 each have a bight 27 formed therein with a rectilinear brace portion 28 interposed between the bight 27 and the intermediate diagonal portion 23 of the form tie 20,21. The rectilinear brace portion 28 extends substantially normal to the generally parallel end portions 22 and 24 of the form tie 20,21 and is an essential feature of the teaching of this invention.
As best shown in FIGS. 2, 3 and 5, the bight portions 25 and 27 of the form tie 20,21 are inserted through holes 12 in the panels 10. The wedge members 14 are then inserted through the projecting portions of the bights 25 and 27 to lock the panels 10 compressively against the tabs 26 and rectilinear brace portions 28 respectively. Thus transverse forces exerted on the panels 10 tending to move them toward each other will place the end portions 22,24 of the form tie 20,21 in compression and transverse forces exerted on the panel members 10 tending to move them away from each other will place the end portions 22,24 of the form tie 20,21 in tension and any movement of the panels 10 toward or away from each other will be resisted. According to this invention, shear forces exerted on the panels 10 will tend to place the intermediate portion 23 of the form tie 20,21 in tension or compression due to the presence of the rectilinear brace portion 28. As best shown in FIG. 5, such rectilinear brace portions 28 extend along the interior surfaces of the panels 10 and thus avoid the cantilever type interconnection of the prior art.
It will be understood that a plurality of form ties 20,21 may be used in a plurality of vertical and horizontal rows in interconnecting panels for a given form. Thus the positions of the plurality of form ties 20,21 may be varied with respect to each other to provide resistance approaching optimum to both shear and transverse forces while utilizing a total amount of material which approaches the minimum.
Referring to FIG. 4, a form tie 40 according to the teaching of this invention is shown which is adapted to interconnect panels 10 at an angle with respect to each other. Thus, one of the end portions 42 of the form tie 40 is shorter than the other end portion 44 thereof. There remainder of the form tie 40 is identical to form ties 20 and 21, it being understood that the intermediate diagonal portion 43 of the form tie 40 may have a length with respect to the spacing of the holes 12 in the panels 10 to enable it to be positioned either as is form tie 20 or as is form tie 21. Other obvious modifications may be made without departing from the teaching of this invention and within the scope of the following claims.
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An article of manufacture for fixing the sides of a form with respect to each other is disclosed, which article consists of a unitary elongated metal member of generally Z-shape configuration having generally parallel end portions joined by an intermediate diagonal portion. Specific structural features of the article are described which provide improved resistance to vertical and horizontal shear forces acting on the form sides in addition to resisting transverse forces which tend to move the form sides toward or away from each other.
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BACKGROUND OF THE INVENTION
1. Field Of The Invention
This invention relates to a mining machine, and more particularly, to a continuous miner which includes a mobile frame assembly and a boom assembly pivotally secured to the mobile frame assembly by a plurality of connectors which distribute the load placed on the boom assembly as the boom assembly is pivoted upwardly from the mobile frame assembly evenly throughout the boom structure, and to a dust collecting system for collecting airborne particles produced as a material dislodging head mounted on the end of the boom assembly dislodges material from a mine face.
2. Description Of The Prior Art
In underground mining, it is well known to provide a continuous mining machine which includes a material dislodging head positioned on the front end of the mining machine for dislodging material from a mine face. The dislodged material is conveyed rearwardly of the mining machine by a conveying system positioned on the continuous mining machine. The continuous mining machine is designed to continuously advance and dislodge material being mined to form an entry or tunnel in the material seam.
Various types of continuous mining machines having different types of tilting of pivoting mining heads are known. U.S. Pat. No. 2,986,384 discloses a mining machine having tiltable, dual mining heads. U.S. Pat. Nos. 3,479,090 and 3,495,876 disclose continuous mining machines each having a pivoting structure for supporting a mining head.
U.S. Pat. No. 3,498,676 discloses a continuous mining machine having a mining head that is positioned at the top of the mine face. The mining head is advanced into the mine face and traversed downwardly through the mine face to cut and break the material out of the mine face. The mining machine is supported on traction treads by which the machine is propelled forwardly to advance the mining head into the mine face.
U.S. Pat. No. 3,499,684 discloses a mining machine with a mining head positioned at the forward end of the machine. Traction means propels the mining machine, and gathering means collects the mined material and transfers the material to a conveyor for moving the mined material to the rear of the machine. The mining head is positioned on a boom that is movable upwardly and downwardly about the transverse axis of a pivot support on the machine main frame.
U.S. Pat. No. 3,516,712 discloses a continuous mining machine with a transverse rotary mining head for mining material from the entire area of the mine face by traversing the mining head through the mine face.
U.S. Pat. No. 3,874,735 discloses a continuous mining machine adapted for low overhead coal seams having a relatively small diameter cutter head of the non-oscillating or fixed head type driven by chains that also cut coal and convey it rearwardly to a gathering head mounted on the front of the machine. The gathering head carries a pair of counter-rotating discs having veins cooperating with conveyor fences for sweeping and discharging coal to a conventional conveyor mounted on the machine chassis.
U.S. Pat. No. 3,966,258 discloses a mining machine having a disintegrating head carried on the front end of the machine by a pivotal link arrangement.
In continuous underground mining, it is also known to provide a mining machine which includes a dust collecting system mounted thereon for collecting airborne dust particles produced as the mining machine cutting or dislodging head operates. The dust collecting system provides a relatively clean environment for the mining machine operator.
U.S. Pat. No. 3,712,678 discloses a continuous miner which is provided with a dust collecting system comprising boom-carried ducting adapted to receive dust-entrained air adjacent and rearwardly of the mining head. The mining machine chassis carries ducting which is operable to alternatively discharge the air to opposite sides of the machine. Counter-rotating centrifugal fans mounted in the boom-carried ducting draw dust-entrained air to such ducting whereby the air flows therethrough to the chassis-carried ducting. Scrubbers or cleaners are operatively associated with the boom-carried ducting for removing larger dust particles from the air.
U.S. Pat. No. 3,810,677 discloses a mining machine having a boom enclosed dust collector assembly for use in a coal mining operation wherein the dusty air from a mining operation is gathered directly from the operation, collected in the mining machine boom and selectively wetted and separated by centrifugal processing into a coal slurry for disposal. The clean air is exhausted to atmosphere. The coal slurry is discharged from the mining machine boom through a flexible hose which lies on the ground along a side of the machine.
U.S. Pat. No. 4,380,353 discloses a dust control system for a mining machine comprising a ductwork system having intakes adjacent the cutter head of the mining machine. A fan draws air through the ductwork system, and a flooded bed scrubber in the ductwork system upstream from the fan entrains the dust in droplets of water. The dust laden water is pumped to a point adjacent the cutting head.
U.S. Pat. No. 4,557,524 discloses a continuous mining machine having a dust control system which includes a generally rectangular intake duct section associated with the boom and a generally rectangular fixed duct section mounted on the vehicle. A transition section is connected to the intake of the fixed duct section. The transition section consists of a two piece arrangement wherein each piece is hinged to the intake duct section and is capable of slidingly engaging the fixed duct section at the end thereof adjacent the boom to sealingly couple the intake duct section to the fixed duct section as the boom swings upwardly and downwardly.
Although the prior art continuous mining machines include various types of cutting heads pivotally mounted on the mining machine, there is a need for an improved mining machine having a boom assembly pivotally connected to the mining machine frame assembly by a plurality of connectors which distribute the load on the mining machine boom assembly as it is pivoted upwardly from the mining machine frame assembly evenly throughout the boom assembly structure. Further, there is a need for a simple efficient dust collecting system whereby dust produced as a dislodging head dislodges material from a mine face is passed through a boom assembly hollow interior portion to a dust collecting system mounted on the mining machine frame. A portion of the boom assembly forms a pivoting joint with a portion of the dust collecting system positioned on the mobile frame assembly to allow airborne dust particles to be withdrawn from the mine face as the boom assembly pivots upwardly and downwardly relative to the mobile frame assembly.
SUMMARY OF THE INVENTION
In accordance with the present invention, there is provided a continuous mining machine for use in an underground mine which includes a mobile frame assembly and a boom assembly extending from the mobile frame assembly. The boom assembly has a first end portion pivotally connected to the mobile frame assembly by a plurality of connecting means and a second end portion spaced from the first end portion. The boom assembly first end portion is pivotally connected to the mobile frame assembly to permit upward and downward pivotal movement of the boom assembly relative to the mobile frame assembly. A material dislodging head is connected to the boom assembly second end portion. The plurality of connecting means are positioned on the boom assembly to distribute the load placed on the boom assembly as it is pivoted upwardly from the mobile frame assembly evenly through the boom assembly structure.
The boom assembly has a hollow interior portion with an air inlet portion connected to the hollow interior portion at the boom assembly second end portion and an air outlet portion at the boom assembly first end portion. A Collecting means is positioned on the mobile frame assembly. The collecting means induces a flow of air through the boom assembly hollow interior portion. As the disloding head operates to dislodge material from a mine face, the collecting means draws airborne dust produced by the disloding head through the hollow interior portion of the boom assembly into the collecting means positioned on the mobile frame assembly. A portion of the boom assembly air outlet portion is pivotally connected to a portion of the mobile frame assembly collecting means to allow the collecting means to continually draw airborne dust from the mine face as the boom assembly pivots upwardly and downwardly relative to the mobile frame assembly.
The continuous mining machine further includes a conveying system which extends longitudinally through the center of the mining machine. The conveying system includes a longitudinal first section which extends from the front end of the mobile frame assembly to the rear end of the mobile frame assembly. The conveying system also includes a conveyor second section pivotally connected to the conveyor first section which extends rearwardly from the rear end of the mobile frame assembly. The conveyor second section is pivotally connected to the conveyor first section for selected lateral and vertical movement relative to the conveyor first section. Material removed from the mine face by the dislodging head is transferred rearwardly of the mining machine along the conveyor system first and second sections by a plurality of spaced flights. The conveyor second section is pivoted relative to the conveyor first section to deposit dislodged material at predetermined locations rearwardly of the mining machine.
Accordingly, the principle object of the present invention is to provide a continous mining machine which includes a boom assembly pivotally connected to the mining machine mobile frame assembly by a plurality of connecting means.
Another object of the present invention is to provide a continuous mining machine having a boom assembly pivotally connected to a mobile frame assembly by a plurality of connecting means suitably positioned on the boom assembly to distribute the loading created on the boom assembly as the boom assembly is pivoted upwardly relative to the mobile frame assembly evenly throughout the boom assembly structure.
A further object of the present invention is to provide a continuous mining machine which includes a dust collecting system positioned on the mobile frame assembly for inducing a flow of air through a hollow interior portion of the boom assembly as the boom assembly pivots upwardly and downwardly relative to the mobile frame assembly.
Still another object of the present invention is to provide a continuous mining machine which includes a conveying system longitudinally positioned on the mobile frame assembly to receive material dislodged from a mine face by a dislodging head and transfer the dislodged material rearwardly from the mine face.
These and other objects of the present invention will be more completely disclosed and described in the following specification, the accompanying drawings and the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a top plan view of a self-propelled continuous mining machine which is the subject of this invention.
FIG. 2 is a view in side elevation of the continuous mining machine shown in FIG. 1, illustrating a boom assembly having a dislodging head secured thereto resting on a mine floor, and illustrating in phantom the boom assembly pivoted upwardly relative to the mining machine to show the extent of travel of the boom assembly.
FIG. 3 is a top plan view of a boom assembly, illustrating in phantom the boom assembly connections to the mining machine.
FIG. 4 is a partial fragmentary view in side elevation of the boom assembly shown in FIG. 3, illustrating a pivoting joint connection which is the subject of this invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to the drawings, and particularly to FIGS. 1 and 2, there is illustrated a continuous mining machine generally designated by the numeral 10 for use in an underground mine to dislodge material from a mine face. Continuous mining machine 10 includes a mobile frame assembly 12 and a pair of ground engaging traction means 14 (one shown) positioned at each side of mobile frame assembly 12 for propelling mining machine 10 within a mine 16 along the floor 18 thereof.
Continuous mining machine 10 is capable of being operated from an operating station 20 in a manner similar to other such machines to dislodge material from a mine face 36 and transport it rearwardly of the rear end 46 of mining machine 10. Accordingly, mining machine 10 includes operating controls and sources of power for operating ground engaging traction means 14 and other equipment included thereon.
Mining machine 10 includes a boom assembly 22 having a first end section 24 pivotally secured to the front end 26 of mobile frame assembly 12. Boom assembly 22 also includes a second end section 28. As seen in FIGS. 1 and 2, a material dislodging head generally designated by the numeral 30 is connected to boom assembly 22 second end section 28. Although a material dislodging head such as dislodging head 30 is illustrated in the Figures, it should be understood that any desired dislodging head 30 known in the art may be secured to boom assembly 22 second end section 28.
Boom assembly 22 also includes four longitudinally extending engaging plates 32 which extend rearwardly from boom assembly 22 first end section 24 to engage four retainers 34 secured to the front end 26 of mobile frame assembly 12. Boom assembly 22 engaging plates 32 are pivotally secured to the mobile frame assembly 12 retainers 34 to allow boom assembly 22 to be pivoted upwardly and downwardly relative mobile frame assembly 12. In this manner, as boom assembly 22 is pivoted upwardly and downwardly relative to mobile frame assembly 12, dislodging head 30 may be operated to dislodge material from a face 36 of the mine 16.
Although not specifically illustrated in the Figures, actuating cylinders, preferably hydraulic cylinders, are connected at one end to front end 26 of mobile frame assembly 12. The other ends of the actuating cylinders are connected to retainers 38 one shown in FIG. 4) on boom assembly 22. As the actuating cylinders extensible rod portions are extended outwardly from their respective cylinder bodies, boom assembly 22 pivots vertically relative to mobile frame assembly 12 to allow dislodging head 30 to dislodge material from the full vertical surface of mine face 36. As seen in FIG. 2, since boom assembly 22 is pivotally connected to mobile frame assembly 12, boom assembly 22 travels in an arcuate path between mine floor 18 and mine roof 40 as dislodging head 30 dislodges material from mine face 36. As also seen in FIG. 2, boom assembly 22 is capable of downward arcuate movement to allow dislodging head 30 to travel below the surface of mine floor 18.
As illustrated in phantom in FIG. 2, since boom assembly 22 is pivotally secured to mobile frame assembly 12, boom assembly 22 travels in an arcuate path from a point beneath mine floor 18 to mine roof 40. As boom assembly 22 pivots upwardly towards mine roof 40, the weight of boom assembly 22 and dislodging head 30 creates torsional loading on the four pivot pins (not shown in FIGS. 1 and 2) which secure boom assembly 22 engaging plates 32 to mobile frame assembly 12 retainers 34. However, since boom assembly 22 is pivotally connected to mobile frame assembly 12 by four engaging plates 32, this four point connection allows the torsional loading created as boom assembly 22 and dislodging head 30 are pivoted upwardly towards mine roof 40 to be evenly spread throughout boom assembly 22. This four point connection reduces the wear on the pivot pins and provides a sturdy connection between boom assembly 22 and mobile frame assembly 12.
Mining machine 10 also includes a dust collecting system generally designated by the numeral 42. Dust collecting system 42 is operable to remove airborne particles produced as dislodging head 30 dislodges material from mine face 36 to provide a clean working environment for the mining machine 10 operator. Dust collecting system 42 includes a fan assembly 44 mounted on mobile frame assembly 12 at the rear end 46 of mining machine 10. Dust collectors 50 is also positioned on mobile frame assembly 12 and is connected to fan assembly 44. Duct assembly 48, which runs longitudinally along mobile frame assembly 12, has an end portion connected to a dust collector 50 and an opposite end portion which extends between a pair of retainers 34 on mobile frame assembly 12. As will be explained later in greater detail, duct assembly 48 includes a top wall 49 and a bottom wall 51 each having formed, arcuate end sections. As will also be explained later in greater detail and illustrated in FIG. 4, boom assembly 22 includes a hollow interior portion 78 and an air inlet 52 which form a part of dust collecting system 42. A portion of boom assembly 22 forms a pivoting joint with the formed, arcuate end sections of duct assembly 48 top wall 49 and bottom wall 51.
As dislodging head 30 operates to dislodge material from mine face 36, fan assembly 44 draws airborne dust produced by dislodging head 30 into boom assembly 22 air inlet portion 52 and through the hollow interior 78 of boom assembly 22 into duct assembly 48 positioned on mobile frame assembly 12. The dust which passes through duct assembly 48 is collected in dust collector 50. As described, dust collecting system 42 withdraws airborne dust from the area adjacent mine face 36 for the safety of the mining machine 10 operator. The pivoting joint formed from duct assembly 48 and boom assembly 22 allows collecting system 42 to draw airborne dust away from mine face 36 as boom assembly 22 is pivoted upwardly and downwardly on mobile frame assembly 12.
Mining machine 10 also includes a conveyor system generally designated by the numeral 54. Conveyor system 54 extends longitudinally from the front end 26 of mobile frame assembly 12 to a location rearwardly of the rear end 46 of mobile frame assembly 12. Conveyor system 54 includes a conveyor first section 56 which extends longitudinally through the center of mobile frame assembly 12. Conveyor system 54 also includes a conveyor second section 58 which extends rearwardly of the rear end 46 of mobile frame assembly 12 and is pivotally connected to conveyor first section 56 for lateral movement relative to conveyor first section 56. In this manner, conveyor second section 58 can be suitably positioned to deposit material provided to conveyor system 54 by dislodging head 30 at a preselected location rearwardly of rear end 46 of mining machine 10. Further, as illustrated in phantom in FIG. 2, conveyor second section 58 may be inclined to conveyor first section 56 if it is desired to deposit the dislodged material into a receiver. Conveyor first and second sections 56, 58 include a common conveyor deck 60. A plurality of spaced flights 62 transport material dislodged by dislodging head 30 rearwardly of the rear end 46 of mining machine 10 along the conveyor deck 60 of conveyor first section 56 and conveyor second section 58.
As seen in FIG. 2, mining machine 10 also includes a stabilizer 64 which is pivotally connected to mobile frame assembly 12. Before mining machine 10 commences operation to dislodge material from mine face 36, stabilizer 64 is extended downwardly to contact mine floor 18. As boom assembly 22 and dislodging head 30 are pivoted vertically relative to mobile frame assembly 12 to dislodge material from mine face 36, stabilizer 64 operates to stabilize the rear end 46 of mining machine 10 to prevent vertical movement of the rear end 46 of mining machine 10.
Referring to FIGS. 3 and 4, there is illustrated boom assembly 22 previously described. Boom assembly 22 includes a generally transverse front wall 66 and a pair of generally longitudinally extending outer sidewalls 68 connected to transverse front wall 66. Generally longitudinally extending outer sidewalls 68 each include a bent portion 69 which provides clearance for the dislodging head 30 drive motors 71.
Boom assembly 22 also includes a horizontally extending top wall 72 and a horizontally extending bottom wall 74. Horizontally extending top wall 72 and horizontally extending bottom wall 74 are connected between the generally longitudinally extending outer sidewalls 68. Horizontally extending top and bottom walls 72, 74 are also connected to transverse front wall 66.
As seen in FIG. 3, top wall 72 and bottom wall 74 each include a generally U-shaped cutout 76. The generally U-shaped cutouts 76 in horizontally extending top wall 72 and horizontally extending bottom wall 74 provide clearance for conveyor first section 56 which passes longitudinally through the center of mobile frame assembly 12.
A pair of longitudinally extending inner sidewalls 70 are connected between horizontally extending top wall 72 and horizontally extending bottom wall 74 as shown in FIG. 3. As seen, the arrangement of generally longitudinally extending outer sidewalls 68, longitudinally extending inner sidewalls 70, transverse front wall 66 and horizontally extending top and bottom walls 72, 74 provide boom assembly 22 with the hollow interior 78 previously described.
As seen in FIG. 3, the pair of generally longitudinally extending outer sidewalls 68 include a pair of outer sidewall plates 32 arranged to be received by a pair of generally U-shaped retainers 34 secured on mobile frame assembly 12 and illustrated in phantom. Similarly, the pair of longitudinally extending inner sidewalls 70 include a pair of inner sidewall plates 32 arranged to be received by another pair of generally U-shaped retainers 34 secured on mobile frame assembly 12 and illustrated in phantom. Outer sidewall plates 32 and inner sidewall plates 32 represent the engaging plates 32 previously described.
Outer sidewall plates 32, inner sidewall plates 32 and the four retainers 34 each include aligned holes to receive four pivot pins 84. As earlier described, boom assembly 22 pivots upwardly and downwardly about pivot pins 84 as the actuating means (not shown) operates to raise and lower boom assembly 22 relative to mobile frame assembly 12. This four pivot pin arrangement evenly distributes the torsional loading placed on boom assembly 22 as boom assembly 22 and dislodging head 30 are pivoted upwardly relative to mobile frame assembly 12. Since the torsional loading is evenly distributed throughout the four pivot pins 84, frictional wearing on each pivot pin 84 is reduced, and the frictional wearing on the pivot pin receiving holes in outer sidewall plates 32 and inner sidewall plates 32 is also reduced.
Referring to FIG. 4, there is illustrated the pivoting joint previously described. The pivoting joint is generally designated by the numeral 57. Horizontally extending top wall 72 and horizontally extending bottom wall 74 include formed, arcuate ends 86 and 88, respectively, positioned between a pair of engaging means 34 illustrated in FIG. 3.
As earlier described, collecting system 42 duct assembly 48 includes duct top wall 49 and duct bottom wall 51 having formed, arcuate ends 53 and 55 respectively. As seen in FIG. 4, horizontally extending top wall 72 and horizontally extending bottom wall 74 arcuate ends 86, 88 contact the inner surfaces of arcuate ends 53, 55 of duct top wall 49 and duct bottom wall 51, respectively, to form pivoting joint 57 between boom assembly 22 and duct assembly 48.
As boom assembly 22 is pivoted upwardly or downwardly relative to mobile frame assembly 12, arcuate ends 86 and 88 pivotally contact the inner surfaces of duct assembly 48 arcuate ends 53 and 55 to provide a sealed, pivoting joint 57. In this manner, as fan assembly 44 operates to draw airborne dust produced by dislodging head 30 through air inlet 52 and boom assembly 22 hollow interior 78, the dust passes through pivoting joint 57 formed by arcuate ends 86, 88 and arcuate ends 53, 55 into duct assembly 48. As boom assembly 22 is raised and lowered relative to mobile frame assembly 12 to allow dislodging head 30 to remove material from the full vertical surface of mine face 36, the dust produced by dislodging head 30 is passed through the hollow interior 78 of boom assembly 22 into duct assembly 48 by means of pivoting joint 57. As seen, collecting system 42 can operate to withdraw airborne dust from mine face 36 regardless of the position of boom assembly 22 relative to mobile frame assembly 12. As described, the pivoting joint 57 formed by arcuate ends 86, 88 and arcuate ends 53, 55 eliminates the need for flexible or telescoping duct connections between duct assembly 48 and boom assembly 22.
According to the provision of the patent statutes, I have explained the principle, preferred construction and mode of operation of my invention and have illustrated and described what I now consider to represent its best embodiments. However, It should be understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically illustrated and described.
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A self-propelled continuous mining machine includes a mobile frame assembly having a front end portion with a boom assembly pivotally retained thereon. The outer end portion of the boom assembly carries a dislodging head for removing material from a mine face. A plurality of connections pivotally connects the boom assembly to the mobile frame assembly. A dust collecting system is positioned on the mobile frame assembly for inducing a flow of air through a hollow interior portion of the boom assembly. As the dislodging head removes material from a mine face, the dust collecting system draws airborne dust created by the dislodging head through a hollow interior of the boom assembly and into the collecting system mounted on the mobile frame assembly. A portion of the boom assembly is pivotally connected to a portion of the collecting system mounted on the mobile frame assembly to provide a pivoting joint to allow the collecting system to draw airborne dust through the boom assembly with the boom assembly in any preselected position relative to the mobile frame assembly. A conveying system mounted on the mobile frame assembly receives material from the dislodging head and transports the material rearwardly of the machine.
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BACKGROUND OF THE INVENTION
Electrical disconnect switches are well known in the prior art. An example of such an electrical disconnect switch is disclosed in U.S. Pat. No. 4,302,643 entitled "Fusible Switch" which is assigned to the same assignee as the present application, and is hereby incorporated by reference.
Electrical disconnect switches interrupt current flowing through an electrical circuit. Opaque covers have been provided for enclosing a switching mechanism within an enclosure and protect personnel against electrical arcing. However, when the disconnect switch is in the closed, or "ON," position the user can not open the cover and visually inspect the position of the current conducting blades. Without a viewing window, the user must turn "OFF" the switch and open the cover to visually inspect the blade position. In certain situations it is desirous to visually inspect the blade position while the switch is "ON".
A need, therefore, exists for an electrical disconnect switch that allows the user to visually inspect the position of the blades without opening the cover of the switch while the switch is in the "ON" position, yet will provide protection in the event of electrical arcing of the switch contacts.
One way of providing a transparent shield that allows users to visually inspect the position of the blades is shown in U.S. Pat. No. 4,110,584 entitled "Load Break Switch With Transparent Internal Shield." However, this design uses a transparent shield that is supported across the front of the switch contacts and is located inside the housing so that it will visually expose the contacts when the cover is open. The transparent shield shown in U.S. Pat. No. 4,110,584 is separate from the cover thus requiring the user to open the cover prior to visually inspecting the contacts or blades. It is desirous to provide a disconnect switch that would allow the user to visually inspect the blades without opening the switch cover as is required by the aforementioned patent.
SUMMARY OF THE INVENTION
The device of the present invention generally relates to electrical disconnect switches and, more particularly, an electrical disconnect switch having a viewing window that allows the user to visually inspect the blade position without opening the cover of the switch. The invention consists of a special cover design having a viewing window for viewing the blades. The design utilizes gaskets that prevent dust, water, and other particles from entering into the electrical switch, thusly, allowing the switch to be approved for dust-tight, drip-tight, water-tight, and corrosion resistant environments. The manner of assembly and design features of this electrical disconnect switch allow it to have the features of a viewing window and also meet all Underwriters Laboratories (UL) and Canadian Standards Association (CSA) requirements for NEMA 12 and NEMA 4, 4x, and 5 switches.
In accordance with one aspect of this invention, there is provided an electrical disconnect switch for interrupting the flow of electrical current having a switching mechanism within an enclosure, a cover attached to the enclosure having an opening therein and a viewing window plate covering the opening, and a viewing window retainer for securing the viewing window plate to the cover.
In accordance with another aspect of this invention, there is provided a method of assembling a viewing window in an electrical disconnect switch comprising the steps of providing an opening in a cover, positioning a gasket against the cover, inserting a viewing window plate against the gasket, placing a retaining plate over the viewing window plate, and securing the retaining plate to the cover.
It is an object of this invention to provide an electrical disconnect switch having a viewing window for visually inspecting the position of the switch blades without opening the switch cover.
Another object of this invention is to provide a method of assembly of a viewing window into an electrical disconnect switch.
Other objects and features of the present invention will become apparent on examination of the following specification and claims together with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of an electrical disconnect switch constructed in accordance with the present invention;
FIG. 2 is a cross sectional view of the electrical disconnect switch of FIG. 1, taken generally along the line 2--2 of FIG. 1; and
FIG. 3 is an exploded, perspective view of the electrical disconnect switch of FIG. 1 showing the electrical disconnect switch with the cover open and the parts that fit into the cover.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
For a better understanding of the present invention together with other and further advantages, and capabilities thereof, reference is made to the following disclosure and appended claims in connection with the above-described drawings.
For exemplary purposes, the invention is shown and described with respect to a three-pole electrical disconnect switch, although the various aspects of the invention are equally applicable to electrical switches having single or multiple of poles. The disconnect switch constructed in accordance with the teachings of the present invention is shown in FIGS. 1-3.
Referring to FIG. 1, an electrical disconnect switch 10 is shown having an enclosure 16 with cover 18 pivotally coupled thereto using a well known rotatable hinging system, such as hinges 17. The enclosure 16 and cover 18 are conventionally formed using sheet metal. Hinges 17 are secured to enclosure 16 and cover 18 through welding, riveting, or some other well known process. Handle 14 interacts with the switching mechanism 12 (FIG. 3) causing the blades (not shown) to close when the handle 14 is in the "ON" position and causing the blades to open when the handle 14 is moved to the "OFF" position. Viewing window 40 is shown having viewing window plate 28 located in an escutcheon 21.
Referring now to FIG. 3, enclosure 16 is shown with cover 18 in the open position exposing switching mechanism 12. Switching mechanism 12 can be constructed using any of the teachings of the prior art, such as the switching mechanism shown in U.S. Pat. No. 4,302,643. However, the switching mechanism shown in U.S. Pat. No. 4,302,643 merely illustrates one of a number of different forms of switching mechanisms in which the present invention may incorporate. As discussed earlier, handle 14 operates the switching mechanism from an "ON" (up) position to an "OFF" (down) position and vice versa.
Locking arm 36 being pivotally coupled to the enclosure 16 engages lock 38, that is coupled to cover 18, when the cover is closed and the handle 14 is in the "ON" position, thusly, preventing cover 18 from being opened. The cover is prohibited from being opened until the user positions handle 14 to the "OFF" position. Locking arm 36 also interacts with the handle 14 to prohibit the disconnect switch from being turned "ON" when the cover 18 is open. Tabs 46 are part of a known external latching system (not shown) that is provided to assure that the cover 18 remains securely closed when the switch is in the "OFF" or "ON" position.
Now referring to FIGS. 2 and 3, cover 18 is shown having a window opening 20 and escutcheon 21. A viewing window plate 28 is pressed against a gasket 26 that is positioned against the cover 18 in the escutcheon 21. The gasket 26 is preferably made of Rubatex® R-114-N and the substantially transparent viewing window plate 28 is made of a shatterproof and flame resistant polymeric material, such as Lexan® MR-5. Gasket 26 prevents entry of water or dust from seeping around the viewing window plate 28. Viewing window retainer 30 is placed over the viewing window plate 28 and maintains the viewing window plate 28 firmly in the cover escutcheon 21. Viewing window retainer 30 is preferably made of stainless steel. Stainless steel closed end pop rivets 24 are inserted through cover rivet holes 22, and through corresponding viewing window retainer rivet holes 34, and are fastened in place to secure the viewing window plate 28 to the cover 18. A pop rivet gasket 32 is disposed between the cover 18 and the viewing window retainer 30 at every pop rivet location. Pop rivet gaskets 32 prevent entry of dust or water into the electrical disconnect switch through cover rivet holes 22.
Viewing window plate 28 is positioned over the switch blades and protects the switch user from arcing when the switch is opened (turned "OFF") while allowing the user a means for visually inspecting the position of the blades prior to opening the cover. For example, if the switch was suppose to be "OFF" (handle in the "OFF" position, allowing the cover to be opened) but has remained "ON" due to a malfunction, the user can immediately see that the switch blades are closed thus indicating to him that proper safety precautions need to be taken prior to opening the cover.
A cover locking flange 42 is disposed on the cover 18 and positioned to correspond to an enclosure locking flange 44 disposed on the enclosure 16 when the cover is closed. Both cover locking flange 42 and enclosure locking flange 44 have locking apertures therein for providing a means for passing a locking means therethrough when the cover is closed to prevent unauthorized opening of the cover.
The present invention may incorporate a fuse puller for allowing ease of fuse removal as shown in U.S. Pat. No. 4,288,138 entitled "Fuse Puller" which is assigned to the same assignee as the present invention, and is hereby incorporated by reference. The present invention is not limited to the use of a fuse puller, it is merely stated here for illustrated purposes.
While there have been shown and described what are at present considered the preferred embodiments of the invention, it will be obvious to those skilled in the art that various changes and modifications may be made therein without departing from the scope of the invention as defined by the appended claims.
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An electrical disconnect switch having a viewing window for viewing the internal switching mechanism is disclosed. The viewing window utilizes gaskets, rivets, a substantially transparent viewing window plate, and a viewing window retainer to provide a dust-tight, water-tight and drip-tight viewing window.
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BACKGROUND OF THE INVENTION
This invention relates to a feed device for the punched paper tape carrying the coded fabric design for loom shed formation dobbies, said device comprising important improvements which facilitate the construction, operation and use of this important dobby member, and which make the use and maintenance of the dobby itself considerably more practical.
SUMMARY OF THE INVENTION
The device according to the invention, of the type in which a feed roller for the punched paper tape is carried at the centre of a spindle mounted in two end supports and rotated intermittently by drive means, is substantially characterised in that said spindle can be disengaged from one of said supports and can rotate with the other relative to the dobby without interrupting the connection between the drive means and punched tape roller. Preferably, the spindle cooperates with said first support by way of a bush which can be disengaged from it by sliding axially against the action of a spring, and is mounted on said second support by means of a clamp allowing axial adjustment and a clamp allowing angular adjustment, a second end bush provided with a front clutch for engaging said drive means being fixed to the end of said spindle close to the second support.
Said drive means comprise a first cam mounted on said spindle between said second support and said second bush, and a second continously rotatable cam conjugate with the first in order to cause it to rotate intermittently.
There are also provided arcuate lever stops which engage with slots in said bushes in order to lock the tape roller in its working position, and cam means rigid with said sencond cam for automatically setting said stops in the locking position on starting the device.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is described in greater detail hereinafter by way of example with reference to a preferred embodiment thereof illustrated by the following drawings, in which:
FIG. 1 is a view of the device according to the invention in its working position;
FIG. 2 shows the device of FIG. 1 in the open position for fitting, replacing and/or extracting the punched tape;
FIGS. 3a and 3b are detailed views of a safety element of the device of FIGS. 1 and 2; and
FIGS. 4 and 5 are two mutually orthogonal views of a convenient form of the control cam for the device of FIGS. 1 and 2.
DESCRIPTION OF THE PREFERRED EMBODIMENT
With reference to the accompanying drawings, the device according to the invention comprises a roller 1, the ends of which carry rings of teeth 2 about which the punched paper tape (not shown) comprising the coded fabric design is wound. The roller 1 is fixed on to a spindle 3 which rotates it intermittently. The spindle 3 carries at one end a bush 4 which is slidable axially against the action of a spring 4' and is normally engaged in a support S of the dobby frame I, and is mounted at its other end in a swivel-mounted support 5 by way of two bushing clamps 6 and 7 both rotatable in respective seats 22 and 23 in the support 5. This support has the general shape of a U, and is pivoted on one of its sides to the dobby frame I by means of a vertical pin 8. The bushing clamp 6 allows axial adjustment of the spindle 3 of the roller 1, against which it is locked by screws 9 when these two pieces are in their required relative position. The bushing clamp 7, which is also locked against the spindle 3 by a screw 10, allows a cam 12 similar to a toothed wheel to be angularly adjusted relative to the spindle 3, this cam being engaged with a further cam 13 disposed at 90° to and conjugate with the first, in order to control the feed of the roller 1. The cam 12 is made rotatably rigid with the spindle 3 by means of an end bush 14 which is similar to the bush 4 and is connected to the cam 12 by means of a front clutch 15 and fixed to the spindle 3 by means of the bushing clamp 7.
By means of this arrangement, it is possible to fit, replace and/or extract the punched paper tape without having to manually disengage and engage the roller 1 as in the past, but by simply rotating the spindle 3 of the roller 1 about the pivoting point 8 of the support 5 so as to pass from the position of FIG. 1 to the position of FIG. 2, after axially moving the bush 4 outwardly against the action of the spring 4' in order to free the spindle 3 from the support S.
FIGS. 3a and 3b show a safety element of the device according to the invention. It consists of a pair of arcuate lever-shaped stops 16 which swivel about an intermediate point 17 and can be controlled at one end 18 in order to lock the roller 1 in the working position of FIGS. 1 and 3b by engaging slots 19 in the bushes 4 and 14, or in order to release it into the paper replacement position of FIGS. 2 and 3a.
If the arcuate levers 16 do not engage the slots 19 when in the position of FIGS. 1 and 3b, this is a sign that the front clutch 15 has not been correctly operated, the consequence of which would be that the design on the punched tape would not be read by the appropriate dobby needles, the operator then being able to act in order to prevent this drawback arising, with considerable advantage for the operation both of the dobby and of the loom.
Again according to the invention, if the operator forgets to insert the arcuate levers 16, when the device is started a cam 20 rotationally rigid with the cam 13 acts during the course of one revolution on the end 21 of the levers 16 in order to swivel them into the position of engagement with the slots 19 in the bushes 4 and 14. After this, the device can operate normally.
The conjugate cams 12 and 13 which control the movement of the roller 1 are shown in FIGS. 4 and 5, which however represent only a preferred embodiment in which the cam 12 is a wheel with rhomboidal teeth 12' and the cam 13 is a wheel provided at its periphery with parallel threads 13' connected together by a single helical connection 13". With cams such as the cams 12 and 13 of FIGS. 4 and 5 (or with cams which are different but are designed according to similar criteria in such a manner as to remain correctly and precisely engaged when the support 5 is rotated in order to disengage the roller 1 from its working position), the cam 13 on rotating with continuous motion transmits intermittent motion to the cam 12. More specifically, each revolution of the cam 13 about its shaft leads to a corresponding advancement of the conjugate cam 12 and thus of the roller 1 through one step.
By using different types of cam 13, it is possible to vary the law governing the rotation of the punched tape roller. In the limit this rotation could be continuous instead of stepwise.
The advantages deriving from the invention compared with dobby tape feed devices already known to the art are apparent. A system which is much more rational, confortable and rapid than in the past is obtained for fitting, replacing and extracting the punched tape on to or from its roller by disengaging one end of the roller spindle and rotating said spindle close to the other end. Operations can be carried out on the punched tape without losing the phase of the fabric design by moving the roller into the aforesaid position. The law governing the tape feed can be varied by simply replacing the control cam 13. Because of the presence of the clutch 18, the punched tape can be fed step by step when this is necessary. Finally, considerable reliability is obtained with respect to the correct positioning of the roller, without the operator being hindered by the presence of the arcuate stop levers which provide this reliability.
Modification can be made to the described embodiment of the device without leaving the scope of the inventive idea.
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In a feed device for the punched paper tape carring the coded fabric design for loom shed formation dobbies, the punched tape roller spindle can be disengaged from one of its end supports and can rotate with the other of said supports to enable the punched tape to be fitted, replaced or extracted, without interrupting the connection between the drive means and punched tape roller.
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CROSS REFERENCE TO RELATED APPLICATIONS
This application claims priority to and the benefit of co-pending U.S. Provisional Application Ser. No. 61/163,705, filed Mar. 26, 2009, the full disclosure of which is hereby incorporated by reference herein.
BACKGROUND
1. Field of Invention
The invention relates generally to the field of oil and gas production. More specifically, the present invention relates to a perforating system having a system for compensating pressure inside a perforating gun body with wellbore pressure.
2. Description of Prior Art
Perforating systems are used for the purpose, among others, of making hydraulic communication passages, called perforations, in wellbores drilled through earth formations so that predetermined zones of the earth formations can be hydraulically connected to the wellbore. Perforations are needed because wellbores are typically completed by coaxially inserting a pipe or casing into the wellbore. The casing is retained in the wellbore by pumping cement into the annular space between the wellbore and the casing. The cemented casing is provided in the wellbore for the specific purpose of hydraulically isolating from each other the various earth formations penetrated by the wellbore.
Perforating systems typically comprise one or more perforating guns strung together, these strings of guns can sometimes surpass a thousand feet of perforating length. In FIG. 1 an example of a perforating system 4 is shown. For the sake of clarity, the perforating system 4 depicted comprises a single perforating gun 6 instead of the typical multitude of guns. The perforating gun 6 is shown disposed within a wellbore 1 on a wireline 5 . The perforating system 4 as shown also includes a service truck 7 on the surface 9 , where in addition to providing a raising and lowering means, the wireline 5 also provides communication and control connectivity between the truck 7 and the perforating gun 6 . The wireline 5 is threaded through pulleys 3 supported above the wellbore 1 . As is known, derricks, slips and other similar systems may be used in lieu of a surface truck for inserting and retrieving the perforating system into and from a wellbore. Moreover, perforating systems may also be disposed into a wellbore via tubing, drill pipe, slick line, coiled tubing, to mention a few.
Included with the perforating gun 6 are shaped charges 8 that typically include a housing, a liner, and a quantity of high explosive inserted between the liner and the housing. When the high explosive is detonated, the force of the detonation collapses the liner and ejects it from one end of the charge 8 at very high velocity in a pattern called a “jet” 12 . The jet 12 perforates the casing and the cement and creates a perforation 10 that extends into the surrounding formation 2 .
FIG. 2 illustrates in side partial sectional view an example of a prior art perforating gun 6 . The perforating gun 6 includes an annular gun tube 16 in which the shaped charges 8 are arranged in a phased pattern. The gun tube 16 is coaxially disposed within an annular gun body 14 . On an end of the perforating gun 6 is an end cap 20 shown threadingly attached to the gun body 14 . On the end of the perforating gun 6 opposite the end cap 20 is a lower sub 22 , also threadingly attached to the gun body 14 . The lower sub 22 includes a chamber shown having an electrical cord 24 attached to a detonator 26 . A detonating cord 28 is included shown having an end connected to the detonator 26 and wound around the gun tube 16 for connection to the lower end of each shaped charge 8 . As is known, an associated firing head (not shown) can emit an electrical signal that transferred through the electrical cord 24 and to the detonator 26 for igniting the detonating cord 28 to then detonate the shaped charge 8 .
An annulus 18 is formed between the gun body 14 and gun tube 16 that typically is at a pressure substantially the atmospheric pressure of the location where the perforating gun 6 is assembled—which is generally about 0 pounds per square inch gauge (psig). Thus at surface 9 , no differential pressure is exerted on the gun body 14 . However, wellbore fluids in a wellbore 1 can generate static head pressure that often exceeds 5,000 psig. Thus when the perforating gun 6 is deployed at depth within the wellbore 1 , the gun body 14 will experience a significant differential pressure. The large pressure difference across the gun body 14 wall requires thicker and stronger walls to enhance their strength, as well as robust seals in a perforating gun 6 .
SUMMARY OF INVENTION
Disclosed herein is a perforating system having a perforating gun with an equalized pressure. The space within the perforating gun body can be pressurized to reduce or eliminate the pressure differential caused by downhole fluid static pressure. The gun body can be pressurized prior to being deployed within a wellbore or can be activated downhole. Optionally, a sealing system can translate downhole pressure to within the gun body for equalizing purposes. Equalizing can occur through a sliding piston or a bladder that transmits pressure.
Also disclosed is an example of a method of perforating that includes pressurizing within a gun body of a perforating system. The perforating system is deployed into a wellbore and shaped charges within the gun body are detonated to create perforations in a side of the wellbore. The step of pressurizing can occur before or after the gun body is inserted into the wellbore. Example methods of pressurizing include: injecting fluid into the gun body to increase pressure therein as well as equalizing pressure in the gun body with ambient pressure to minimize pressure differential across the wall of the gun body.
BRIEF DESCRIPTION OF DRAWINGS
Some of the features and benefits of the present invention having been stated, others will become apparent as the description proceeds when taken in conjunction with the accompanying drawings, in which:
FIG. 1 is partial cutaway side view of a prior art perforating system in a wellbore.
FIG. 2 is a side sectional view of a prior art perforating gun.
FIG. 3 is a side sectional view of an embodiment of a perforating gun having an equalizing bladder.
FIG. 4 is a side sectional view of an embodiment of a perforating gun having a combustible material.
FIG. 5A is a side sectional view of an embodiment of a perforating gun having a slidable piston.
FIG. 5B is a side sectional view of an embodiment of a perforating gun having an expandable bladder.
FIG. 6 is an axial sectional view of an embodiment of a perforating gun in accordance with the present disclosure.
FIG. 7 is a side partial sectional view of a perforating system as described herein deployed in a wellbore.
While the invention will be described in connection with the preferred embodiments, it will be understood that it is not intended to limit the invention to that embodiment. On the contrary, it is intended to cover all alternatives, modifications, and equivalents, as may be included within the spirit and scope of the invention as defined by the appended claims.
DETAILED DESCRIPTION OF INVENTION
The present invention will now be described more fully hereinafter with reference to the accompanying drawings in which embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the illustrated embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Like numbers refer to like elements throughout. For the convenience in referring to the accompanying figures, directional terms are used for reference and illustration only. For example, the directional terms such as “upper”, “lower”, “above”, “below”, and the like are being used to illustrate a relational location.
It is to be understood that the invention is not limited to the exact details of construction, operation, exact materials, or embodiments shown and described, as modifications and equivalents will be apparent to one skilled in the art. In the drawings and specification, there have been disclosed illustrative embodiments of the invention and, although specific terms are employed, they are used in a generic and descriptive sense only and not for the purpose of limitation. Accordingly, the invention is therefore to be limited only by the scope of the appended claims.
With reference now to FIG. 3 an example of a perforating gun 40 is provided in a side partial sectional view. As shown, the perforating gun 40 includes an annular gun body 44 having an upper end cap 42 coaxially attached at one end and lower end cap 55 on an opposite end. A lower sub 54 is coaxially defined within an end of the gun body 44 opposite the upper end cap 42 . In the example of FIG. 3 , the lower sub 54 is a tubular segment coaxial with the gun body 44 and capped with the lower end cap 55 . Coaxially secured within a portion of the gun body 44 is a gun tube 46 thereby defining an open space annulus 48 (also referred to herein as a plenum) between the gun tube 46 and gun body 44 . The gun tube 46 is an annular member with apertures formed through the side wall and shaped charges 50 inserted within the apertures; a detonating cord 52 is shown connecting to each of the shaped charges 50 . In the embodiment shown, a bladder 64 encases the gun tube 46 on its outer surface providing a sealing barrier between the gun tube 46 and the annulus 48 . The bladder 64 can be a flexible member made from an elastomer or other polymer material, or can also be a foil-like metal. In the example of FIG. 3 , the bladder 64 is a sleevelike member having ends attachable to either the outer surface of the gun tube 46 or the end cap 42 /bulkhead 61 .
A solid bulkhead 61 is shown mounted in the gun body 44 and in a plane transverse to an axis A X of the perforating gun 40 . In an example, the bulkhead 61 defines the lower end of the gun body 44 and upper end of the lower sub 54 . Bulkhead 61 spans the entire space within the gun body 44 . A lower bulkhead 60 is shown provided within the lower sub 54 in a plane substantially parallel to that of the first bulkhead 61 and defining a chamber 58 between the bulkheads 60 , 61 . An orifice 56 formed through a lateral wall of the gun body 44 provides fluid communication between the chamber 58 and the space surrounding the perforating gun 40 . For example, prior to deployment the chamber 58 would freely communicate air at atmospheric pressure through the orifice 56 . Similarly, when deployed in a fluid filled wellbore, wellbore fluid can flow into the chamber 58 through the orifice 56 driven by the higher pressure in the wellbore. Eventually, as the wellbore fluid enters the chamber 58 , the pressure in the chamber 58 equalizes with wellbore pressure. A passage 62 axially formed through the bulkhead 61 provides fluid communication from the chamber 58 into the annulus 48 in the space between the gun body 44 and the bladder 64 . The fluid communication from the space ambient the perforating gun 40 into the annulus 48 pressurizes the annulus 48 to substantially ambient pressure thereby minimizing pressure differential across the wall of the gun body 44 . The bladder 64 prevents fluid migration into the gun tube 46 , thus avoiding damaging or fouling the shaped charge 50 by wellbore fluid.
Shown in FIG. 4 is a side sectional view of an embodiment of a perforating gun 40 A that includes an oxidizing material for pressurizing within the gun body 44 . In this example embodiment, the bulkheads 61 , 60 are shown substantially the same as the embodiment of FIG. 3 ; including the passage 62 formed through the first bulkhead 61 . Added in this embodiment is an oxidizing agent 68 within the chamber 58 between the gun tube 46 and lower sub 54 A. An example oxidizing agent 68 is combustible, and can also combust in the absence of oxygen or when exposed to wellbore fluid. In the example of FIG. 4 , the oxidizing agent 68 is in the process of being combusted and producing off gases. Arrows illustrate flow of the off gases from within the chamber 58 , through the passage 62 , and into the annulus 48 . The combustion off gas pressurizes the annulus 48 to substantially reduce or eliminate stresses on the gun body 44 from an applied pressure differential. Other alternatives for use in the chamber 58 to produce pressure within the gun body 44 include chemical reactions, gas generators or slow burn elements.
With reference now to FIG. 5A , an alternative example of a perforating gun 40 B is shown in a side partially sectional view. In this embodiment, the perforating gun 40 B includes a gun body 44 , an end cap 42 on the end of the gun body 44 , and a lower sub 54 B on the gun body 44 end opposite the end cap 42 . The gun tube 46 is shown axially anchored within the gun body 44 defining an annulus 48 between the gun body 44 and gun tube 46 . In this example, a bulkhead 61 A is at the lower terminal end of the gun tube 46 to form a boundary between the gun body 44 and lower sub 54 B. The lower sub 54 B is shown as a largely annular member having an open space with a pressure chamber 70 . A piston 72 is coaxially provided in the pressure chamber 70 and having seals 73 optionally provided on the outer radial periphery of the piston 72 . The piston 72 is axially moveable within the pressure chamber 70 ; a pressure differential axially applied across the piston 72 can urge the piston 72 within the pressure chamber 70 in a direction along the axis A X . A port 76 is shown formed on through a lateral wall of the lower sub 54 B allowing fluid and pressure communication into the pressure chamber 70 on a side of the piston 72 opposite from the bulkhead 61 A. When the perforating gun 40 B is in a wellbore, higher pressure wellbore fluid can flow through the port 76 and into the pressure chamber 70 and urge the piston 72 upwards towards the bulkhead 61 A. Passages 74 are axially formed through the bulkhead 61 A allowing fluid communication between the chamber 70 and the annulus 48 . A fluid such as hydraulic fluid, air, an inert gas, nitrogen, combinations thereof and the like, can be in the annulus 48 and in pressure chamber 70 between the bulkhead 61 A and the piston 72 . The fluid can be at atmospheric pressure, or pressurized above atmospheric. Urging the piston 72 towards the bulkhead 61 A pressurizes the fluid in the annulus 48 and chamber 70 thereby to equalize pressure in the annulus 48 with ambient pressure to minimize gun body 44 wall differential pressure. Alternatively, the piston 72 can be replaced with an expandable bladder 75 shown having ends sealed within the chamber 70 and along an inner circumference of the chamber 70 . The bladder 75 can include folds so that when fluid enters the chamber 70 through the port 76 , the bladder 75 “unfolds” towards the gun tube 46 and pressurizes the pressurizing fluid in the annulus 48 and side of the bladder 75 facing the gun tube 46 .
Referring now to FIG. 6 , an example of a perforating gun 40 C is shown in a partially sectional axially view. In this embodiment, a valve 78 is provided through an opening 80 formed in the wall of the gun body 44 A. A pressurized gas, such as nitrogen or air, can be injected through the valve 78 and into the annulus 48 between the gun body 44 a and gun tube 46 . Deploying a relatively inert gas, such as nitrogen, reduces chances of harm to the shaped charge 50 , detonating cord 52 , or associated electronics (not shown). In this example, the shaped charge 50 includes a case 49 , a liner 51 in the case, 49 , and high explosive 53 between the liner 51 and case 49 . Pressurizing the space in the annulus 48 increases the pressure within the gun body 44 A which in turn can minimize pressure differentials across the wall of the gun body 44 as the gun 40 C is disposed in a pressurized wellbore. As is known, detonating the high explosive 53 , produces a force to expel the liner 51 from the case 49 . The liner 51 is further inverted by the explosive force into a metal jet used to perforate a formation adjacent a wellbore.
Illustrated in a side partial sectional view in FIG. 7 is an example of use of a perforating system as described herein deployed within a wellbore 96 on a wireline 94 . In this example, a perforating system 82 is shown having multiple perforating guns 84 that can be the same or similar to the perforating guns 40 , 40 A, 40 B, 40 C described in FIGS. 3-6 . While deployed in the wellbore 96 , shaped charges 86 in the perforating system 82 can be detonated to emit metal jets 88 that form perforations 90 within the adjoining subterranean formation 92 . A surface truck 102 is shown at surface 98 for raising/lowering, and communicating with the gun string. The wireline 94 attaches the string with the surface truck 102 and is wound through pulleys 10 in a derrick structure. Advantages of reducing the pressure differential across the wall of the gun body 44 are reduced size and weight of the gun body 44 , that can result in more and/or larger shaped charges 50 included with a perforating gun and a perforating gun system.
The present invention described herein, therefore, is well adapted to carry out the objects and attain the ends and advantages mentioned, as well as others inherent therein. While a presently preferred embodiment of the invention has been given for purposes of disclosure, numerous changes exist in the details of procedures for accomplishing the desired results. These and other similar modifications will readily suggest themselves to those skilled in the art, and are intended to be encompassed within the spirit of the present invention disclosed herein and the scope of the appended claims.
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A perforating system having a perforating gun with a pressurizable gun body. The gun body can be pressurized prior to deployment in a wellbore, or while in the wellbore. Pressurizing the gun body can include adding fluid into the gun body, such as a pressurized gas, a liquid, or combustion products. A seal diaphragm can be used to transfer wellbore pressure into the gun body.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an optical encoder having an electrical division circuit for use in an encoder used for a displacement measurement or an angle measurement.
2. Related Background Art
A photoelectronic encoder is basically constructed by including a main scale having a first optical grating formed thereon, an index scale having a second optical grating formed thereon and arranged so as to face the main scale, a light source for irradiating the main scale with light, and a photoelectric receiving element for receiving light which has been transmitted or reflected by the optical grating of the main scale to be transmitted through the optical grating of the index scale. A system using an array of photoelectric receiving elements doubling as an index scale in a photoelectronic encoder of this sort has already been proposed, and an example thereof is shown in FIG. 10 .
A conventional optical encoder shown in FIG. 10 is such that a plurality of photoelectric receiving elements are directly formed on an index scale 10 so as for their pitch to match the pitch of an optical grating 3 of a main scale 1 . That is to say, after formation of an oxide film 12 on an n type semiconductor substrate 11 , the oxide film 12 is selectively removed away so as for its pitch to match the pitch of the optical grating 3 , and then a p type impurity is diffused into the n type semiconductor substrate 11 with the oxide film 12 as a mask to thereby form a p type semiconductor layer 13 . As a result, a photodiode is formed in the form of a pn junction between the n type semiconductor substrate 11 and the p type semiconductor layer 13 . Then, a transparent current collecting layer 14 is formed over the entire surface of the n type semiconductor substrate 11 to thereby form the index scale 10 .
In accordance with the conventional optical encoder, since the light emitted from the light source 5 only passes through one optical grating, the photoelectric receiving efficiency is enhanced, and the influence of noises due to the diffracted light is excluded. In addition, since the index scale 10 itself constitutes the photoelectric receiving element, the device can be miniaturized.
FIG. 7 shows the relationship between an example of a pattern of the photodiode array used in the above-mentioned encoder and a light and darkness pattern of detected light. In FIG. 7 , photodiode groups A and B are arranged with the positional relationship in which they are 0° and 90° out of phase with the light and darkness pattern of the light, and photoelectric currents generated therein are inputted to an I-V conversion circuit (not shown).
The photoelectric currents generated with such a construction, at the time when the light and darkness pattern of the light crosses the diode groups, are converted into voltages in the I-V conversion circuit so that analog sine voltage signals which are 0° and 90° out of phase with the light and darkness pattern of the light are obtained.
FIG. 8 shows an example of a conventional resistive division circuit which is capable of dividing the pitch of a primary signal into sixteen parts.
In FIG. 8 , reference numeral 20 A designates a buffer amplifier for an A sin θ signal; reference numeral 20 B designates a buffer amplifier for an A cos θ signal; reference numeral 22 designates an inversion amplifier for applying an −A sin θ signal obtained by inverting an output signal of the buffer amplifier 20 A to a node of a resistor array 16 ; reference numerals 24 A to 24 H designate eight comparators which are provided in correspondence to nodes of the resistor array 16 , respectively; reference numeral 26 designates a reference voltage setting unit for supplying a reference voltage Vr for comparison to each of the comparators; reference numerals 28 A to 28 F designate exclusive OR gates for composing logically output signals of the comparators 24 A to 24 H; reference numeral 30 , a direction discriminate circuit; and 32 , an oscillator.
Since in this resistive division circuit 15 , resistance values of resistors R 1 , R 2 , R 3 and R 4 are set so as to meet the ratio of 1:0.707:0.707:1 and also 180° are divided into eight parts, in the case of 360°, sixteen division can be made.
By the way, since this resistive division circuit is disclosed in detail in Swiss Patent No. 407,569, the detailed description thereof is omitted here for the sake of simplicity.
The light and darkness pattern of the light obtained in the photoelectric receiving element group in such a manner allows the pulse signals having a higher resolution than that optically obtained to be obtained through the I-V conversion amplifier and the electrical division circuit. Hence, positional and rotational information having a high accuracy is obtained.
FIG. 9 shows the relationship between an input signal and an output signal of the comparator 24 A of the above-mentioned resistive division circuit shown in FIG. 8 .
In the figure, reference symbol Va designates an input signal to an inverting input of the comparator 24 A, and reference symbol Vr designates an input signal to a non-inverting input of the comparator 24 A. In this case, the level of the input signal Vr is set to 0 V.
Normally, each of these comparators has a hysteresis as a measure of coping with the chattering due to noises.
For this reason, the output signal is not switched with its polarity at zero cross, but has a certain voltage (0.1 V for the amplitude of 1 V in FIG. 9 ) hysteresis. Since if the rotational direction of the encoder is fixed, a quantity of shift due to the hysteresis is uniform, this seems to have no problem. However, in the resistive division circuit shown in FIG. 8 , the magnitude of the input voltage of the camparator 24 C is 1/√{square root over (2)} of that of the input voltage to the comparator 24 A, and hence if the same hysteresis voltage is set, then a quantity of shift will vary. In addition, if the rotational direction is changed, then as shown in FIG. 9 , the polarity of the input signal Va is not changed at the position of the ideal zero cross, but is switched at a certain voltage. Here, since each of the comparators has the hysteresis, the position where the magnitude of the pulse is switched is shifted for the hysteresis.
A comparator adapted to detect a signal level is thus allowed to have a hysteresis so as to avoid the influence of signal noises generated on the input side of an electrical division circuit when an analog output signal from such an encoder head as shown in the prior art example is electrically divided by utilizing the resistive division method, to thereby suppress the generation of the chattering or the like.
However, there is encountered a problem in that since if the comparator is made to have the hysteresis, then the polarity of a pulse is switched at the position different from the position of the actual zero cross, the proper position can not be detected. In addition, there is encountered another problem in that since the switching point of a pulse when the direction is inverted as shown in FIG. 9 is largely changed due to the influence of the hysteresis, which results in a large error in the position where the direction inversion is repeated as right before the stop or the like.
SUMMARY OF THE INVENTION
In the light of the foregoing, the present invention has been made in order to solve the above-mentioned problems associated with the prior art, and it is, therefore, an object of the present invention to provide an optical encoder in which a signal 180° out of phase with a detection signal is inputted on the reference voltage side of a comparator constituting an electrical division circuit to thereby solve the problems of occurrence of the difference in the influence of hysteresis due to the amplitude and occurrence of an error during inversion of the rotational direction, resulting from the conventional hysteresis.
Other objects and constitution of the present invention will become clear by following description of the preferred embodiments of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic circuit diagram showing a configuration of an electrical division circuit according to a first embodiment of the present invention;
FIGS. 2A and 2B are respectively graphical representations useful in explaining the relationship between an input signal and an output signal of a comparator 42 A shown in FIG. 1 in the form of comparison with a signal output in the prior art example;
FIG. 3 is a diagram showing an example of arrangement of a photodiode array constituting a second embodiment of the present invention;
FIG. 4 is a circuit diagram showing a configuration of an electrical division circuit in the second embodiment of the present invention;
FIGS. 5A and 5B are respectively graphical representations useful in explaining the relationship between an input signal and an output signal of a comparator 42 A in the second embodiment;
FIG. 6 is a circuit diagram showing a configuration of an electrical division circuit in a third embodiment of the present invention;
FIG. 7 is a diagram useful in explaining the relationship between an example of a pattern of a conventional photodiode array and a light and darkness pattern of detected light;
FIG. 8 is a circuit diagram showing a configuration of a conventional electrical division circuit;
FIG. 9 is a graphical representation useful in explaining the relationship between an input signal and an output signal of a comparator 42 A in a conventional electrical division circuit; and
FIG. 10 is a cross sectional view showing a construction of one example of a conventional optical encoder.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The preferred embodiments of the present invention will hereinafter be described in detail with reference to the accompanying drawings.
First Embodiment
FIG. 1 is a schematic circuit diagram showing a configuration of an electrical division circuit used in the present embodiment. Conventionally, a certain reference voltage is inputted to one input terminal of a comparator for comparison. However, in the present embodiment, as shown in FIG. 1 , the electrical division circuit is configured in such a way that a signal 180° out of phase with the other input signal generated by a resistor array 41 is inputted to one input terminal of a comparator. FIGS. 2A and 2B show the relationship between an input signal and an output signal of a comparator 42 A shown in FIG. 1 for example in the form of comparison with the conventional signal output. From FIG. 2B , it is understood that a point at which the polarity of a pulse is switched after the inversion operation is largely changed. More specifically, with respect to the pulse switching point before the inversion operation, an inverting input of the comparator 42 A is at the level of +0.05, whereas after the inversion operation, the inverting input of the comparator 42 A is at the level of −0.05. In FIGS. 2A and 2B , this quantity of position shift is about 3% of one cycle of a sine wave.
Since in the case of a circuit configuration shown in FIG. 1 , one cycle of the sine wave is divided into sixteen parts, this quantity of position shift corresponds to a quantity of shift of 48% in 3×16, i.e., about one half one pulse in terms of pulse divided into sixteen parts.
Conventionally, the reference voltage is inputted to the non-inverting input of the comparator 42 A, whereas in the present embodiment, a signal 180° out of phase with the input signal to an inverting input of the comparator 42 A is generated through a resistor array 41 to be inputted to the non-inverting input of the comparator 42 A. As apparent from FIG. 2B , when a disturbance signal such as a noise is generated in the input signal to the inverting input of the comparator 42 A, the chattering is generated. Since in the present embodiment, a pulse is switched through the differential operation, the input signal is hardly influenced by the above-mentioned disturbance signal. Also, since the hysteresis can also be further reduced as compared with the conventional one, the position shift during the inversion operation can also be reduced.
In addition, in the case as well where a D.C. offset is superimposed on an input signal, since in the present embodiment, the comparison is carried out through the differential operation, it becomes unnecessary to remove the D.C. offset.
When a quantity of light of a light emission portion varies, the amplitude of an output signal varies accordingly. In such a case as well, since conventionally, the hysteresis of the comparator exerts a large influence on an input signal, an error is caused. However, in the present embodiment, since the hysteresis is less, its influence is reduced accordingly.
Second Embodiment
FIG. 3 is a diagram showing one example of arrangement of a photodiode array constituting an optical encoder according to a second embodiment of the present invention.
In FIG. 3 , a width of a photodiode is made to correspond to one-fourth of one cycle of a light and darkness pattern of detected light. Thus, the photodiodes are arranged so as to correspond in phase to 0°, 90°, 180° and 270° with the light and darkness pattern of the light, respectively. The four photodiodes for one cycle S 1 , S 2 , S 3 and S 4 are decided as one segment. In FIG. 3 , it is understood that three segments of photodiodes are arranged.
The light and darkness pattern of the light having one cycle corresponding to one segment of photodiodes are moved over the photodiode array so that signals corresponding in phase to 0°, 90°, 180° and 270° with the light and darkness pattern of the light, respectively, are generated in the photodiodes S 1 to S 4 .
FIG. 4 is a circuit diagram showing a configuration of an electrical division circuit in the second embodiment of the present invention. In the figure, reference numerals 43 A to 43 D designate I-V conversion circuits for converting the photoelectric currents generated in the photodiode array consisting of the photodiodes S 1 to S 4 into voltages, respectively. Reference numerals 44 A to 44 D designate differential amplifiers for arithmetically processing the voltage signals obtained through the I-V conversion in the I-V conversion circuits 43 A to 43 D, respectively.
The differential amplifier 44 A receives as its input the output voltage signals from the I-V conversion circuits 43 A at the −terminal of the 44 A and 43 C+a certain constant voltage Vref 2 at the +terminal of 44 A to carry out the arithmetic operation therefor to thereby output an output signal A.
The differential amplifier 44 B receives as its input the output voltage signals from the I-V conversion circuits 43 B at the −terminal of 44 B and 43 D+a certain constant voltage Vref 2 at the +terminal of 44 B to carry out the arithmetic operation therefor to thereby output an output signal B.
The differential amplifier 44 C receives as its input the output voltage signals from the I-V conversion circuits 43 C at the −terminal of 44 C and 43 A+a certain constant voltage Vref 2 at the +terminal of 44 C to carry out the arithmetic operation therefor to thereby output an output signal C.
The differential amplifier 44 D receives as its input the output voltage signals from the I-V conversion circuits 43 D at the −terminal of 44 D and 43 B+a certain constant voltage Vref 2 at the +terminal of 44 D to carry out the arithmetic operation therefor to thereby output an output signal D.
From these four output signals A to D, there are obtained the signals corresponding in phase to 0°, 90°, 180° and 270°, respectively.
In the first embodiment, the signals corresponding in phase to 180° and 270°, respectively, are obtained by inverting the phases of the output signals A (0°) and B (90°) in the inversion amplifiers to be inputted to a part of the resistor array. However, in the second embodiment, the output signals C and D corresponding in phase to 180° and 270°, respectively, similarly to the output signals A and B, are obtained by arithmetically operating the signals from the photodiode array to be inputted to a part of the resistor array.
FIGS. 5A and 5B , similarly to FIGS. 2A and 2B , show the relationship between the input signal and the output signal of the comparator 42 A in the present embodiment.
When we fear disturbance signals due to noises, since in the first embodiment, the noise components generated in the output signals A and B, respectively, are inputted to the resistor array after passing through the respective inversion amplifiers, even if the disturbance signals generated in the photodiode array and the signal processing circuit are inputted to the comparators after the differential operation is carried out therefor, they are not removed (refer to FIG. 5A ).
However, in the second embodiment, since the signals corresponding in phase to 180° and 270°, similarly to the signals corresponding in phase to 0° and 90°, are arithmetically operated without through any of the inversion amplifiers, as shown in FIG. 5B , the disturbance signal to the non-inverting input of the comparator is in phase with the disturbance signal to the inverting input thereof. Consequently, if such a signal passes through the comparator, then the disturbance component is removed, and hence that signal does not suffer the influence of the disturbance noise.
As described above, the electrical division is carried out using the four output signals A to D, whereby it is possible to obtain the signal which shows the withstanding against the disturbance due to noises and also is free from the influence of the hysteresis in a comparator.
Third Embodiment
FIG. 6 is a circuit diagram showing a configuration of an electrical division circuit in a third embodiment of the present invention.
In the prior art example, and the first and second embodiments, the signals obtained after the I-V conversion are arithmetically operated in the respective differential amplifiers to be inputted to the electrical division circuit. However, in the present embodiment, after the output signals from the photodiode group consisting of the photodiodes S 1 , S 2 , S 3 and S 4 are subjected to the I-V conversion, the resultant signals are inputted to the electrical division circuit in their entirety.
While D.C. component signals of the photoelectric currents generated in the photodiodes S 1 to S 4 are changed in accordance with a quantity of light, these changes in the signals from the photodiodes S 1 to S 4 are equal to one another.
Thus, if such signals are inputted through the differential operation in comparators as in the circuit configuration of the present embodiment, then the influence of the D.C. components is cut to allow the objective comparator outputs to be obtained.
If such a circuit configuration is adopted, then the differential amplifiers become unnecessary to make it possible to reduce the number of components or parts. In addition, the removal of the differential amplifiers allows the error components contained in these amplifiers to be eliminated. As a matter of course, since the number of components or parts is reduced, it is possible to reduce the power consumption and the circuit scale.
Also, at this time, since the effects inherent in the present proposal are maintained, similarly to the present embodiment, it is possible to obtain a signal which shows the withstanding against the disturbance due to noises and also is free from the influence of the hysteresis in each comparator.
As set forth hereinabove, according to the present invention, in an electrical division circuit for use in an optical encoder, a circuit configuration of the present proposal is adopted, whereby it is possible to obtain a signal which shows the withstanding against the disturbance due to noises and also is free from the influence of the hysteresis in each comparator.
As many apparently widely different embodiments of this invention may be made without departing from the spirit and scope thereof, it is to be understood that the invention is not limited to the specific embodiments thereof except as defined in the appended claims.
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In an optical encoder, an output signal of the encoder and a signal inverted from the output signal are respectively inputted to one input terminal and the other input terminal of a comparator constituting a circuit for electrically decomposing the output signal of the encoder, whereby it is possible to obtain a highly accurate electrical division circuit which is capable of removing the hysteresis of a comparator, noises and D.C. offset.
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FIELD OF THE INVENTION
[0001] This invention generally relates to polishing slurries used in a CMP process and more particularly to polishing slurry compositions and methods for polishing an oxide layer having metal filled semiconductor features included in semiconductor wafer process surface to reduce feature sidewall erosion.
BACKGROUND OF THE INVENTION
[0002] Planarization is increasingly important in semiconductor manufacturing techniques. As device sizes decrease, the importance of achieving high resolution features through photolithographic processes correspondingly increases thereby placing more severe constraints on the degree of planarity required of a semiconductor wafer processing surface. Excessive degrees of surface non-planarity will undesirably affect the quality of several semiconductor manufacturing process including, for example, photolithographic patterning processes, where the positioning the image plane of the process surface within an increasingly limited depth of focus window is required to achieve high resolution semiconductor feature patterns.
[0003] In the formation of conductive interconnections, copper is increasingly used for forming metal interconnects such as vias and trench lines since copper has low resistivity and good electromigration resistance compared to other traditional interconnect metals such as aluminum. The undesirable contribution to electrical parasitic effects by metal interconnect residual resistivity has become increasingly important as device sizes have decreased. One problem with the use of copper relates to its relatively high degree of softness making it subject to high differential material removal rates compared to adjacent dielectric insulating oxide materials during planarization processes such as chemical mechanical polishing (CMP).
[0004] CMP planarization is typically used several different times in the manufacture of a multi-layer semiconductor device. For example, CMP is used as one of the processes in preparing a layered device structure in a multi-layer device for subsequent processing. CMP is used to remove excess metal after filling anisotropically etched semiconductor features with metal to electrically interconnect the several layers and areas that make up a multi-layer semiconductor device.
[0005] CMP generally includes placing a process surface of the wafer in contact against a flat polishing surface, and moving the wafer and the polishing surface relative to one another. The polishing action is typically aided by a slurry which includes for example, small abrasive particles such as colloidal silica (SiO 2 ) or alumina (Al 2 O 3 ) that abrasively act to remove a portion of the process surface. Additionally, the slurry may include chemicals that react with the process surface to assist in removing a portion of the surface material, the slurry typically being separately introduced between the wafer surface and the polishing pad. During the polishing or planarization process, the wafer is typically pressed against a rotating polishing pad. In addition, the wafer may also rotate and oscillate back and forth over the surface of the polishing pad to improve polishing effectiveness.
[0006] There are also several different types of slurries used in the CMP process. The most common abrasives used are silica (SiO 2 ), alumina (Al 2 O 3 ), ceria (CeO 2 ), titania (TiO 2 ), and zirconia (ZrO 2 ). The abrasives are typically formed using two different methods that result in fumed and colloidal abrasives. Fumed abrasives include agglomerated particles that are larger in size than the dispersed, discrete particles of colloidal abrasives. For the same solids concentration, the removal rate using a fumed abrasive is higher than that using a colloidal abrasive due to sharp edged particle features and a broader particle size distribution in fumed abrasives. For the same reasons, the defect density using a fumed abrasive also tends to be higher.
[0007] To minimize defect formation, the colloidal abrasives having a more uniform particle size distribution are preferred. However, to achieve the same material removal rate as using a fumed abrasive, the solids concentration of a colloidal slurry must be almost three times higher. The higher required solids concentration undesirably increases the cost of the slurry and leads to difficult to clean surface residues.
[0008] One particular problem with the prior art methods of CMP involve the unique problems associated with the use of low-k (low dielectric constant) materials as an inter-layer dielectric (ILD) together with copper filled features. For example, poor adhesion between the copper and the low-k material causes peeling back of the ILD layer at the copper sidewall to occur upon subjecting the polishing surface to CMP stresses. Other defects associated with CMP of copper together with low-k materials include erosion along the ILD layer/copper feature interface (feature sidewall erosion) in both relatively wide copper areas such as bonding pads and relatively long and narrow copper filled areas such as trench lines having high pattern density.
[0009] Further, the lower strength of the low-k materials has led to increased vulnerability of copper/low-k systems to CMP induced defects caused by slurries using abrasives with relatively high hardness such as fumed alumina and silica. On the other hand, slurries with colloidal particles including alumina and silica require excessively high solids content which is believed to contribute to feature sidewall erosion and difficult to clean surface residues. For example, typical slurries in the prior art have included a relatively high solids content of about 6% to about 25% by volume. The relatively high solids content tends to increase polished material residue and slurry residue accumulation within eroded or dished portions of the surface requiring extensive cleaning processes to fully remove the accumulated residues. In addition, other chemical characteristics of prior art slurries such as pH and polishing methods adapted for polishing one layer of material in a copper CMP process may not be conducive to achieving optimal surface planarity during the polishing of other material layers underlying the copper layer. As such, it has been difficult to develop CMP methods including abrasive slurries that can accomplish both requirements of an acceptable material removal rate while minimizing the introduction of defects at the semiconductor wafer surface including feature sidewall erosion.
[0010] For example, referring to FIG. 1A, a cross sectional side view of a portion of a semiconductor wafer is shown having a copper filled feature e.g., 12 , for example a bonding pad or trench line, is formed in ILD layer 14 A by an anisotropic etching process. The feature is typically filled with copper layer 16 B by an electroplating process after forming an adhesion/barrier layer e.g., 16 A, for example tantalum nitride (TaN) to line the feature opening. The feature openings are anisotropically etched into a low-k dielectric material ILD layer 14 A formed of, for example, carbon or fluorine doped oxide, and one or more layers of an oxide 14 B, for example having an ARC coating, for example formed of silicon oxynitride (e.g., SiON) and an optional oxide capping layer, for example SiO 2 , formed overlying the ILD layer 14 A.
[0011] Referring to FIG. 1B, in a typical CMP process, the excess copper in copper layer 16 B above the feature level is first removed followed by removal of an overlying adhesion/barrier layer 16 A above the feature level. Finally an oxide CMP polishing process, using a slurry containing a polishing formulation according to the prior art is then used to remove the oxide layer 14 B and buff or remove residual scratches in the ILD layer 14 A. During the polishing process, feature sidewall erosion, for example as shown at 18 A at the ILD layer/copper interface forms a sidewall recess with acts to trap slurry and polished material residue. In addition, peeling of the ILD layer away from the copper filled feature during CMP frequently occurs. Further, the presence of recessed areas in the copper feature surface caused by dishing or erosion during the CMP process compromises device electrical reliability.
[0012] For example referring to FIG. 1C is shown a feature profile at line A1 as obtained by a profilometer measurement of a copper filled bonding pad following a CMP process including an oxide polishing process according to the prior art. Shown on the vertical axis is relative depth in Angstroms from the wafer surface adjacent the copper bonding pad. Shown on the horizontal axis is the distance in microns along the wafer surface including the copper bonding that the profilometer is passed over (scan length). The sidewall recesses are indicated at A2 and A3 having a depth of about 1400 Angstroms.
[0013] Therefore, there is a need in the semiconductor art to develop a slurry composition and method for polishing a metal filled semiconductor feature to reduce CMP induced defects including sidewall feature erosion.
[0014] It is therefore an object of the invention to provide a slurry composition and method for polishing a metal filled semiconductor feature to reduce CMP induced defects including sidewall feature erosion while overcoming other shortcomings and deficiencies in the prior art.
SUMMARY OF THE INVENTION
[0015] To achieve the foregoing and other objects, and in accordance with the purposes of the present invention, as embodied and broadly described herein, the present invention provides a slurry system for a chemical mechanical polishing (CMP) process and a method for using the same wherein the slurry system includes an aqueous dispersion comprising at least abrasive polymer containing particles in an alkaline solution having a pH of less than about 10; and wherein the method includes providing a semiconductor wafer process surface including a oxide containing material and metal filled semiconductor features; providing the system; and, polishing in a CMP process the semiconductor wafer process surface using the slurry system to remove at least a portion of the oxide containing material and the metal comprising the metal filled semiconductor features.
[0016] These and other embodiments, aspects and features of the invention will be better understood from a detailed description of the preferred embodiments of the invention which are further described below in conjunction with the accompanying Figures.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] [0017]FIGS. 1A and 1B are conceptual cross sectional side view representations of an exemplary semiconductor feature including following a copper CMP process according to the prior art.
[0018] [0018]FIG. 1C is a profilometer diagram representing a profilometer scan over a copper bonding pad indicating sidewall recesses according to a CMP process including an oxide polishing process according to the prior art.
[0019] [0019]FIGS. 2A through 2C are conceptual cross sectional side views of an exemplary semiconductor feature formed including a CMP process using the CMP oxide polishing process according to an embodiment of the present invention.
[0020] [0020]FIG. 3 is a profilometer diagram representing a profilometer scan over a copper bonding pad indicating sidewall recesses according to a CMP oxide polishing process according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0021] Although the slurry system according to present invention is explained with reference to copper semiconductor features formed in a low-k dielectric material layer associated with a multilayer semiconductor device, it will be appreciated that the slurry system may be advantageously used in a CMP process to polish copper semiconductor features formed in having an adjacent oxide containing material layer. In addition, although the method of the present invention is explained with reference to an exemplary relatively wide area copper filled semiconductor feature, for example a bonding pad, it will be appreciated that the slurry system may advantageously be used for polishing any copper filled semiconductor feature where it would be advantageous to reduce erosion and/or dishing of the feature in a CMP process including polishing an oxide layer adjacent a copper filled (damascene) semiconductor feature including vias, trench lines and dual damascene features. In addition, while the slurry system of the present invention is advantageously used to polish a copper filled (damascene) semiconductor feature it will be appreciated that it may advantageously be used with other metal filled (damascene) features to achieve the goals of reducing sidewall recess formation, increasing surface planarity, and reducing ILD layer peeling in a CMP process. As used herein, the term “copper” is meant copper and alloys thereof. The term “low-k” means having a dielectric constant of less than about 3.2.
[0022] In a first embodiment of the invention a slurry system is provided for polishing a metal filled semiconductor feature in a CMP process including polymeric abrasive particles in an alkaline solution. In an important feature of the invention, the slurry system preferably has a pH of less than about 10.0, preferably between about 7.0 and about 10.0 in an oxide/copper CMP polishing step. For example, in the prior art, alkaline slurries having a pH of greater than about 10.0 are typically used in oxide/copper polishing processes to prevent particle agglomeration and sedimentation of inorganic slurry particles. Among the advantages of the slurry system of the present invention, the polymer containing particles, preferably having a polymeric surface for contacting a polishing surface, allow a less alkaline slurry system to be used, for example in a copper/oxide material polishing process thereby advantageously reducing oxide dissolution while avoiding particle agglomeration to improve polishing planarity. For example, the polymeric particles have an iso-electric point that prevents agglomeration of the particles at relatively lower pH compared to metal oxide particles.
[0023] Preferably the abrasive polymer containing particles are colloidal particles have a mean diameter of about 20 nm to about 500 nm, more preferably about 50 nm to about 200 nm. The term “particle” as it is used herein refers to both agglomerates of more than one primary particle and to single (unagglomerated) or primary particles, however the “mean particle diameter” as used herein refers to the mean diameter of the primary particle whether agglomerated with other primary particles or not. The term “mean particle diameter” additionally refers to a mean diameter taken from a statistically significant sampling of the average equivalent spherical diameter of primary particles when using a particle size determination means including TEM image analysis. Preferably the polymeric abrasive particles included in the slurry system have a particle size distribution with greater than about 90 percent of the particles having a particle size of less than about 200 nm.
[0024] In another important feature of the invention, the slurry system preferably has an abrasive polymer containing particle solids content of about 0.5 weight % to about 10 weight %, more preferably about 4.0 weight % to about 6 weight %, with respect to a slurry volume weight. For example, it has been found that using a slurry having a reduced abrasives solids content compared to prior art processes, that sidewall erosion to form recesses or divots at the copper/ILD layer interface is reduced (e.g., a trench in the dielectric layer surrounding the copper inter connect line). It is believed that together with the relatively softer, including elastomeric characteristics, of the polymer containing abrasive particles and the relatively lower solids content of the slurry system, that sidewall erosion in copper filled features is reduced by minimizing the incidence of and force of impact and abrasion at the sidewall portions of the feature.
[0025] In another preferred embodiment, the slurry system of the present invention includes a basic solution containing at least one of ammonium hydroxide (NH 4 OH), ammonia (NH 3 ), and tetra methyl ammonium hydroxide (TMAH).
[0026] In another preferred embodiment, the slurry system of the present invention optionally includes a surfactant or wetting agent from about 0.01 weight % to about 0.5 weight %. Although a wide variety of surfactants known in the art may be suitably used, preferably the surfactant includes a surfactant selected from the group of fatty acids and salts thereof, for example, a soap or detergent, where the fatty acid or salt thereof has one or more polar groups such as COOH, SO 3 H, PO 3 H and mixtures thereof. For example, the addition of a surfactant, for example a fatty acid derived soap or detergent, improves the planarity in a CMP polishing process and reduces sidewall erosion, due to what is believed to be due to reduced friction between the polymeric particles and the polishing surface. Other suitable surfactants include glycols, aliphatic polyethers, and akoxylated alkyphenols.
[0027] Preferably the polymer containing abrasive particles are formed of an elastomeric polymer material, for example polyurethanes, neoprenes, silicones, fluorosilicones, fluorocarbon polymers, polysulfones, acrylic resins, polyacetals, saturated polyesters, polyamides, polyimides, polypropylenes, phenol resins, urea resins, melamine resins, epoxy resins, and the like. In one embodiment, polyurethane elastomers are preferred since they have high compressibility, high tensile strength and high modulus. Generally, a harder the elastomer results in a correspondingly lower the compressibility. This combination provides optimal toughness and durability and is one of the distinctive characteristics of polyurethane elastomers. Further, the properties of elastomeric polymers are easily altered by chemical additives and processing conditions that are well known in the art to alter the hardness, for example, over a range of about 70D to about 100D according to an elastomer durometer hardness test. Elastomeric polymer containing particles including mono-dispersed particles may be made by conventional methods at the preferred mean diameters and particle size distributions sizes by methods known in the art. Other polymeric materials may suitably be used to form the polymer containing particles including low hardness thermoplastic materials, such as polyether- and polyester-based polyurethanes, polyvinyl chlorides, fluoroelastomers and the like.
[0028] Alternatively, the polymeric material may be coated onto base colloidal inorganic particles such as silicon dioxide (SiO 2 ), titanium dioxide (TiO 2 ) and cerium oxide (CeO 2 ), or mixtures thereof by conventional methods including sol-gel precipitation methods to form the polymeric containing particles. In an important feature of the invention the polymeric abrasive particle exhibits elastic behavior to allow partial absorbtion of impact forces, for example, when an abrasive particle impacts a feature sidewall at the feature/ILD layer interface.
[0029] In operation, the polymeric abrasive particle slurry system of the present invention provides a system whereby the polymeric particles are at least partially elastic and compressible such that a lower localized compressive force is applied to the polishing target surface, a portion of the applied compressive force being absorbed by the compressible base particles. As a result, the application of the proper compressive force to the target polishing surface, for example about 5 PSI to about 10 PSI is locally modified by the force absorbing characteristics of the polymeric particles so as to smooth variations in the applied compressive force to the polishing target surface thereby avoiding application of excessive forces that result in erosion of copper filled semiconductor features including peeling of the adjacent ILD layer. The polymeric containing particles are also believed to act to equalize distributed forces across the polishing target surface, for example a semiconductor wafer, thereby reducing dishing and erosion effects.
[0030] For example, the present invention may be advantageously used for CMP of low-k materials alone or in conjunction with metal filled features. Exemplary low-k inorganic materials include, for example, carbon doped oxide (C-oxide), fluorine doped oxide (e.g., fluorinated silicate glass), porous oxides, xerogels, or SOG (spin-on glass). The metal filled features may suitably include for example, tungsten (W), aluminum (Al), and copper (Cu), and alloys thereof.
[0031] While the slurry system of the present invention may be used on a wide variety of systems, it is advantageously used with low-k materials including copper conducting areas such as bonding pads and metal interconnect lines to prevent peeling, among other advantages, of the uppermost low-k dielectric layers associated with a multilayer device.
[0032] For example, referring to FIG. 2A is shown a semiconductor feature, for example a copper filled bonding pad 20 formed in a dielectric insulting layer 22 A, for example formed of a low-k (low dielectric constant) material also referred to as an inter-layer dielectric (ILD) layer. The copper filled bonding pad overlies and is in electrical communication with and underlying conductive areas (not shown). An oxide layer 22 B is formed over the ILD layer 22 A including at least one of a capping layer, for example SiO 2 and an ARC layer, for example silicon oxynitride (e.g., SiON). The low-k ILD layer 22 A is preferably SiO 2 based, for example, carbon or fluorine doped silicon oxides as are known in the art, but may additionally include organic ILD layers including an oxide capping layer such as an SiO 2 or silicon oxynitride (e.g., SiON) capping layer. Exemplary organic low-k materials include polyarylene ether, hydrogen silesquioxane (HSQ), methyl silsesquioxane (MSQ), polysilsequioxane, polyimide, benzocyclobutene, and amorphous Teflon.
[0033] Still referring to FIG. 2A, a bonding pad opening is first formed by photo-lithographically patterning and anisotropically etching the ILD layer 22 A followed by the blanket deposition of an adhesion/barrier layer 24 A at a thickness from about 50 Angstroms to about 150 Angstroms to line the bonding pad opening. An electro-chemical deposition (ECD) process is then used to deposit copper layer 24 B over a seed layer of copper (not shown) deposited according to CVD or PVD methods over the adhesion/barrier layer 24 A. The ECD copper layer is deposited by conventional ECD methods to fill the bonding pad opening including a portion of the copper layer 24 B above the feature level.
[0034] Referring to FIG. 2B, in a copper CMP process, typically a first CMP process step is carried out to remove the excess copper overlying the feature level in copper layer 24 B followed by a second CMP process step to remove the adhesion/barrier layer 24 A above the feature level to at least partially expose the underlying oxide layer 22 B. The first and second CMP processes are carried out with conventional slurry systems and polishing pads as are known in the art, preferably using slurry systems optimized for removing the copper layer 24 B in the first CMP process and at least partially removing the adhesion/barrier layer 24 A in the second CMP process.
[0035] Referring to FIG. 3B, a third CMP step is then carried out using the slurry system according to preferred embodiments of the present invention in an oxide polishing process to remove a remaining portion of the adhesion/barrier layer 24 A and the oxide layer 22 B and to polish the ILD layer 22 A to buff or remove scratches in the ILD layer remaining from previous CMP processes. It will be appreciated that the same polishing pad may be used from a previous adhesion/barrier CMP process, however, preferably, a different polishing pad is used to minimize cross contamination. In addition, it will be appreciated that a wide assortment of polishing pads and polishing pad material with varying hardness are available that may be suitably used with the slurry system of the present invention. In one embodiment, the polishing pad used in the third CMP process is formed of the same material as the polymeric abrasive particles, for example an elastomeric polyurethane polishing pad having a hardness equal to or greater compared to the polymer containing abrasive particles to minimize pad deformity. It will be appreciated that the polishing pads may further be stacked to minimize pad deformation during polishing. For example polyurethane polymeric particles having a measured durometer hardness of about 75D are used with a polyurethane polishing pad having a durometer hardness of about 95D. The use of a polishing pad with a polishing pad having a higher hardness compared to the polymeric abrasive polymers, for example having a hardness about 10 percent to about 25 percent harder than the polymeric abrasive particles is believed to enhance the various advantages of the slurry system according to the present invention including reducing feature sidewall recess formation, improving global and local planarity to reduce surface topography, and to reduce the incidence of ILD layer peeling form the metal filled feature sidewall.
[0036] For example, referring to FIG. 3 is shown a feature profile shown as line B1 as obtained by a profilometer measurement of a copper filled bonding pad following a CMP process including an oxide polishing process using the slurry system according to an embodiment of the present invention. The data can be compared with the prior art results shown in FIG. 1C where the third CMP process or oxide polishing process was carried out using a prior art slurry system. Shown on the vertical axis is relative depth in Angstroms from the wafer surface adjacent the copper bonding pad. Shown on the horizontal axis is the distance in microns along the wafer surface including the copper bonding that the profilometer is passed over (scan length). The sidewall recesses are indicated at B2 and B3 having depths about 600 to about 700 Angstroms with an average overall recess depth of about 300 Angstroms. It is seen that compared to prior art processes both the overall average recess depth of the bonding pad including sidewall erosion is reduced.
[0037] The preferred embodiments, aspects, and features of the invention having been described, it will be apparent to those skilled in the art that numerous variations, modifications, and substitutions may be made without departing from the spirit of the invention as disclosed and further claimed below.
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A slurry system for a chemical mechanical polishing (CMP) process and a method for using the same wherein the slurry system includes an aqueous dispersion comprising at least abrasive polymer containing particles in an alkaline solution having a pH of less than about 9.5; and wherein the method includes providing a semiconductor wafer process surface including a oxide containing material and metal filled semiconductor features; providing the system; and, polishing in a CMP process the semiconductor wafer process surface using the slurry system to remove at least a portion of the oxide containing material and the metal comprising the metal filled semiconductor features.
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CROSS REFERENCE TO RELATED APPLICATIONS
This application is related to U.S. patent application Ser. No. 10/658,814 filed on Sep. 8, 2003, by Kevin J. Surace and Marc U. Porat, entitled “Acoustical Sound Proofing Material and Methods for Manufacturing Same”, which is incorporated by reference herein in its entirety.
FIELD OF THE INVENTION
This invention relates to materials for improving the security of rooms and buildings and in particular to novel laminated construction materials which reduce radio frequency (“RF”) signal transmission compared to the RF signal transmission through normal building materials thereby to prevent undesired RF signal transmission from or into the protected room or building.
BACKGROUND OF THE INVENTION
The security of information, such as that transmitted by radio frequency waves, is emerging as a privacy, economic, security, and anti-terrorism issue. In spite of security technologies such as data encryption, information may be surreptitiously obtained by sensing the emissions of keyboards, wireless mouse pointing devices, computer monitors, security systems and such. Unintended listeners may receive the emissions of telephone systems outside the user's premises. Employees may make calls with cell phones and inadvertently transmit background sounds or conversations. Some restaurants, theaters, churches and other public places want to prevent cell phones or pagers from being used. In some cases the information represented by the signals may not be important, but the signals themselves interfere with nearby sensitive equipment. Thus it is important in many circumstances to contain emissions within, and/or to prevent emissions from penetrating, a certain room or building.
Prior solutions have typically used electrically conducting materials, such as wire mesh or sheet metal, to enclose the volume of interest. The conducting materials are mechanically and electrically connected together and then grounded. Installation is done by building an enclosure a layer at a time. For example, one method in use today is to weld steel plates together on six sides of a room, with an opening for a door, typically steel. This method is labor intensive, requires a highly trained labor force, may require heavy duty material handling equipment, and the resulting structure slowly loses its RF shielding ability over time as small cracks develop in the welds due to building motion and/or settling.
In areas requiring high security it is also desirable to be able to detect attempts to penetrate the protected area to, for example, install a secret listening or viewing device.
Accordingly, what is needed is a new material and a new method of construction to reduce the transmission of RF signals into or out of an enclosure which allows easier construction, does not deteriorate over time, and is tamper resistant. The ability to simultaneously reduce acoustic energy (i.e. sound) transmission from or into the enclosure is also desirable.
SUMMARY OF THE INVENTION
In accordance with this invention, a new laminated structure and associated manufacturing process is provided which significantly improves the ability of a wall, ceiling, floor or door to reduce the transmission of RF waves from or into a room. As an added feature, the materials of this invention resist tampering.
The materials of the laminated structure of this invention are similar to those described in the aforementioned U.S. patent application Ser. No. 10/658,814, but with the center material (FIG. 1 and FIG. 2 of the application Ser. No. 10/658,814) specified to be electrically conductive. As described in application Ser. No. 10/658,814, the outermost materials of the laminated structure of this invention (sometimes hereinafter referred to as a “panel” or “stack”) may be gypsum, wood, or other suitable materials. Relative to the laminated structure described in application Ser. No. 10/658,814, one embodiment of the present invention further comprises a conductive tape which is in electrical contact with the electrically conductive center material and which extends beyond at least one end of the laminated structure by an amount which will allow the tape to be wrapped around at least one end or edge of the structure and attached to an exterior surface of the structure. When the resulting structure, which in one embodiment is typically provided in 4×8 foot sheets, is attached to electrically conductive metal studs by electrically conductive screws (typically metal) which penetrate the conductive center material, the panel is thereby electrically connected to the metal studs. The metal studs are electrically connected to ground potential.
In accordance with an embodiment of the invention, a strip of electrically conductive tape is used to cover the seam where two adjacent panels come together. The electrically conductive tape covering the seam is in electrical contact with the electrically conductive tape extending from the abutting edge of each panel (this last tape is further connected with the electrically conductive center material). As a result electrical connection is provided between all of the panels so connected, as well as to the metal studs. The electrically conductive materials of the panels so connected are at essentially the same potential and when grounded or held at a fixed potential the net effect is to mitigate any impinging RF waves.
Walls and ceilings are typically constructed using panels having gypsum outer layers; floors and doors are typically constructed with panels having wood for the outer layers. Of course, other appropriate materials can be used for the outer layers if desired.
Another embodiment of the invention provides for room construction using wood instead of metal studs or floor joists. The panels are installed on the wooden studs in a similar fashion to their installation on metal studs as described above, but with one or more shorting bars located on the studs at one or more predetermined locations such that the metal screws attaching the panels to the studs will penetrate the one or more shorting bars, which in turn are grounded. In one embodiment the screws are wired together across the back side of the panels.
In another embodiment the panels are installed in at least two courses (i.e. two or more layers) wherein the panels of the second (outer) course are staggered so as to cover up the seams between the pairs of abutting panels of a first inner course. The metal screws attaching the second course panels also penetrate the conductive layer of the panels of the first course, thereby electrically connecting all panels. By covering the seams between panels of the first course, the second course of panels prevents RF signals from leaking through the seams.
While in one embodiment tape is used to cover all seams in the multi-layer structure of panels, alternative embodiments of this invention using two or more layers of panels omit the additional strip of conductive tape between panels of the first course, or omit the additional strip of conductive tape between panels of the second course, or omit the additional strip of conductive tape between the panels of the first and second courses.
As an added benefit of this invention, the panels of this invention not only attenuate RF signals but also attenuate acoustic signals.
If desired, three or more courses of panels can be used as part of a wall or ceiling or floor and the additional strips of conductive tape which cover the seams between abutting panels of each course can be omitted selectively from one or more of the courses.
An advantage of this invention is that the panels are all electrically connected together and to ground and seams between adjacent panels in each layer of panels are sealed either by electrically conductive tape or by an additional course of panels placed over the seams or by both tape and the additional course of panels.
BRIEF DESCRIPTION OF THE DRAWINGS
This invention will be described in more detail in conjunction with the following detailed description taken together with the drawings.
FIG. 1 shows a laminated structure fabricated in accordance with this invention for reducing the transmission of RF through the structure.
FIG. 2 shows another embodiment of a laminated panel fabricated in accordance with this invention and a method for attachment of the panel to a metal stud.
FIG. 3 shows a method for attaching adjoining panels to a metal stud.
FIG. 4 shows a method of attaching panels to a conductive, grounded shorting bar and non-conducting studs.
FIG. 5 shows a method of attaching multiple courses of panels to metal studs.
FIGS. 6A through 6H are graphs showing the attenuation ability of the laminated panels of this invention as a function of the frequency of the signals being attenuated.
FIG. 7 shows an embodiment of this invention for electrically contacting a cut edge on a panel.
DETAILED DESCRIPTION OF THE INVENTION
Definition of Terms:
DCID 6/9
A directive from the Director of the
Central Intelligence (DCI) titled:
Physical Security Standards for
Sensitive Compartmented Information
Facilities
PSA
Pressure sensitive adhesive.
RF
Radio frequency waves.
SCIF
Sensitive Compartmented Information
Facility: An accredited area, room,
group of rooms, buildings, or
installation where Sensitive
Compartmented Information (“SCI”) may
be stored, used, discussed, and/or
processed. SCIF performance
requirements and design details are
given in DCID 6/9.
WIFI
“Wireless fidelity”: popular term for
a high-frequency wireless local area
network (WLAN).
PANEL
A laminated structure constructed in
accordance with the present invention.
The panel may be further attached to a
structure defining a room or a wall.
The structure of FIG. 1 is an example of the laminated structure of one embodiment of the present invention. The layers in the structure will be described from the top to the bottom with the structure oriented horizontally as shown. It should be understood, however, that the laminated structure of this invention will be oriented vertically when placed on vertical walls and doors, as well as horizontally or even at an angle when placed on ceilings and floors. Therefore, the reference to top and bottom layers is to be understood to refer only to these layers as oriented in FIG. 1 and not to the actual use of this structure wherein this structure may be placed vertically, horizontally, or at an angle between vertical and horizontal. A detailed discussion of the method of construction and the materials of the laminated structure of FIG. 1 and various alternative embodiments is given in the aforementioned U.S. patent application Ser. No. 10/658,814 and is not repeated here.
In FIG. 1 , a portion of two adjacent panels 100 - 1 and 100 - 2 is shown. Note that the spaces shown between the layers and the edges of the panels are for illustrative purposes only. References to the “center material” or “center layer”, as in layer 110 of FIG. 1 , are understood to mean the “electrically conductive layer” of the laminated layers of a panel, whether or not this layer is physically in the center. For example, in some embodiments the conductive layer is last in the stack of layers. As described in U.S. patent application Ser. No. 10/658,814, top layer 102 is glued to a center layer 110 using a thin viscoelastic adhesive 106 . The material of layer 110 is selected for its electrical conduction properties. In one embodiment, the conductive material of center layer 110 is a sheet of metal, such as silicon steel plus copper. In other embodiments center layer 110 can be a copper alloy or aluminum, or a steel sheet with an adjacent copper wire mesh, mu metal or the like. The thickness of the conductive layer 110 may be as thin as foil or up to about a half-inch thick, selected for a certain purpose depending upon the degree of rigidity, acoustic damping, RF signal transmission reduction or physical security desired. In one embodiment the conductive center layer 110 is conductive paint or conductive adhesive.
A conductive tape 122 , such as 3M-1345 obtained from 3M Manufacturing, is attached to the center layer. The tape that is preferred for use with this invention to seal the cracks between abutting panels is 3M-1345 tape which is described by 3M as “embossed tin-plated copper foil shielding tape”. As described in the 3M data sheet, this tape “consists of an embossed 1-ounce deadsoft tin-plated copper foil backing and an aggressive pressure-sensitive acrylic adhesive. The edges of the embossed pattern pressed into the foil cut through the adhesive layer to establish reliable metal-to-metal contact between the backing and the application substrate.” This tape is available in standard and custom widths and lengths. Widths vary from ¼ inch to 23 inches. This tape is intended for use in “applications requiring excellent electrical conductivity from the application substrate through the adhesive to the foil backing. Common uses include grounding and EMI shielding in equipment, components, shielded rooms . . . [and similar structures]. The tin plating on the copper coil backing facilitates soldering and improves resistance to oxidation and discoloration.” The 3M data sheet reports that “typical shielding effectiveness (far field) is in the range of 75 dB to 95 dB (30 MHz to 1 GHz).”
In accordance with this invention, the tape applied to the edges of the panels is long enough to extend completely along (i.e. to “span”) each edge of a panel (such as the edge which extends perpendicular to the plane of the paper in FIG. 1 ) and is sufficiently wide such that a portion ( 122 - 2 and 122 - 3 ) of the tape 122 extends out from the edge far enough to be pulled around to the top surface of layer 102 as shown in FIG. 1 . The conductive tape 122 may have on one surface thereof a PSA for convenience of construction. The PSA provides for the electrically conductive material of the tape to make electrical contact with a portion of a surface of electrically conductive layer 110 by rolling or otherwise applying pressure to the tape. The conductive tape is applied to and extended along at least the major (longer) edges of a panel. In some embodiments the conductive tape is applied to all edges. In another embodiment conductive tape 122 is replaced by a metal channel or strip. The channel or strip is sized to extend along an edge of a panel in electrically conductive contact with the center conductor 110 with a portion of the channel strip extending out from the edge and being bent to contact the front surface, as described above and in FIG. 1 in conjunction with tape. The formed metal channel or strip is fastened to the layers of the structure using rivets, screws, PSA, or other electrically conductive attachment means.
If desired, a slight indentation can be provided in the portion of the surface of electrically conductive layer 110 to which the tape 122 or metal channel/strip is attached to make the outer surface of the tape 122 or metal channel/strip flush with the adjacent surface of layer 110 .
A thin layer of viscoelastic glue 114 is applied to the lower surface of center layer 110 so as to attach the center layer 110 to the bottom laminated layer 118 . In one embodiment layers 114 and 118 are omitted so that layer 110 is visible and is one external side of the panel 100 .
Upon installation, for example attaching 4×8 foot panels side by side to a wall, another layer 126 of conductive tape is affixed over the seam between the panels as shown in FIG. 1 . Tape 126 electrically connects the tapes 122 of adjoining panels. Of course, in an actual structure, the tapes 122 of abutting panels will ideally be in physical contact.
The dimensions of a room utilizing panels constructed according to the invention may not be the same as the dimensions of one or more panels. Panels may be cut to any arbitrary size. However, such cutting exposes an edge of the laminated structure without conductive tape 122 . Referring to FIG. 2 , conductive tape 122 is applied to extend over and along the edge exposed by cutting the panel so as to cover completely this edge. The edges 122 - 3 and 122 - 4 of the tape 122 are bent ninety degrees (90°) back over the panel 100 so as to electrically connect these edges to the edge-adjacent portions of the front and back surfaces of the panel 100 . An electrically conductive metal screw 204 is inserted through the top portion 122 - 3 of tape 122 , conductive layer 110 , and metal stud 206 , as shown in FIG. 2 . A portion 122 - 4 of tape 122 may extend far enough across the bottom of layer 118 ( 110 in some embodiments) for screw 204 to penetrate this portion of tape 122 . The center portion 122 - 2 of tape 122 electrically contacts the edge of center layer 110 exposed by cutting.
In one embodiment, stud 206 may be of a nonconductive material and screws 204 may be grounded by other means, such as an electrically conductive strip of material 402 ( FIG. 4 ) extending along the face of the nonconductive stud 206 but in electrical contact with screw 204 and electrically grounded or held at a fixed potential.
FIG. 3 illustrates one installation of two panels 100 - 1 and 100 - 2 shown mounted with adjacent edges of the two panels 100 - 1 and 100 - 2 abutting and attached to a single metal stud 304 . A metal screw 204 - 1 attaches the laminated panel 100 - 1 to stud 304 . Screw 204 - 1 penetrates center layer 110 - 1 , thus completing an electrical connection between the center layer 110 - 1 and the grounded stud 304 . The space shown between the edges of panels 100 - 1 and 100 - 2 is for ease of explanation and, of course, does not exist in the actual structure.
Panel 100 - 2 is similarly attached to stud 304 by means by metal screw 204 - 2 . Metal screw 204 - 2 again penetrates through electrically conductive tape 126 and through panel center layer 110 - 2 of panel 100 - 2 extending into metal stud 304 . Thus the center layer 110 - 1 of panel 100 - 1 is electrically connected via electrically conductive metal screw 204 - 1 , electrically conductive metal stud 304 and electrically conductive metal screw 204 - 2 to center layer 110 - 2 of panel 100 - 2 and the two panels will be at the same electrical potential. In addition, electrically conductive tape 126 is placed over the two edges 103 - 1 and 103 - 2 of panels 100 - 1 and 100 - 2 . While screws 204 - 1 and 204 - 2 are shown as having their heads external to tape 126 , in an alternative embodiment these screws will have their heads covered by tape 126 and in some embodiments the heads will be countersunk into the panels 100 - 1 and 100 - 2 so that the tops of the heads are flush with the surfaces of these panels. Tape 126 will then lie flat over these countersunk heads. Electrically conductive tapes 122 - 1 and 122 - 2 of the panels 100 - 1 and 100 - 2 will be in electrically conducting contact with each other when the panels 100 - 1 and 100 - 2 are mounted on stud 304 such that edges 103 - 1 and 103 - 2 are in physical contact with each other (i.e. directly abut). The structure of FIG. 3 thus ensures that panels 100 - 1 and 100 - 2 are electrically grounded and at the same electrical potential thereby to effectively reduce if not eliminate RF transmissions through these panels from one side to the other.
Referring to FIG. 4 , in one embodiment wood studs 404 shown in side view are substituted for metal studs. A grounded conductive shorting bar 402 is arranged behind panels 100 - 1 and 100 - 2 and at least one metal screw 204 per panel 100 connects the center layer 110 (not shown) to shorting bar 402 . In another embodiment at least one metal screw 204 per panel 100 is wired to ground.
In an alternative embodiment to that shown in FIG. 4 , the grounded conductive shorting bar 402 can be replaced by a vertical electrically conductive shorting bar (not shown) placed along each wooden stud such that screws 204 - 1 a through 204 - 1 g through panel 100 - 1 go through the electrically conductive shorting bar running parallel to and attached to the stud 404 - 2 . In this case, a separate electrical connection connecting each of the individual electric shorting bars can be provided although in one embodiment such electrical connection is inherently provided by center layer 110 of each panel 100 .
Furthermore, as shown in FIG. 4 , a plurality of metal screws 204 - 1 a through 204 - 1 g are used to attach panel 100 - 1 to center stud 404 - 2 . Likewise, a similar plurality of electrically conductive metal screws 204 - 2 a through 204 - 2 g are used to attach panel 100 - 2 to the same stud 404 - 2 . As shown in FIG. 4 , panels 100 - 1 and 100 - 2 are attached to stud 404 - 2 such that the directly adjacent edges of these panels covered respectively by tapes 202 - 1 and 202 - 2 mounted along the edges of the panels as described above, directly abut and therefore are in electrically conductive contact with each other. To ensure, however, that these tapes 202 - 1 and 202 - 2 are at the same potential, the electrically conductive screws 204 - 1 a through 204 - 1 g and 204 - 2 a through 204 - 2 g connect the tapes 202 - 1 and 202 - 2 to the center layers 110 - 1 and 110 - 2 within panels 100 - 1 and 100 - 2 respectively via grounding bars. Grounding bars 402 mounted horizontally across the studs 404 - 1 , 404 - 2 and 404 - 3 as shown in FIG. 4 are perpendicular to each of the studs 404 - 1 through 404 - 3 and ensure that the panels such as 100 - 1 and 100 - 2 are at essentially the same electrical potential at all points within the panels.
Although not shown in FIG. 4 , electrically conductive tape 126 can be placed over the seam between panels 100 - 1 and 100 - 2 shown in FIG. 4 to extend along the edge portions of tapes 202 - 1 and 202 - 2 which are visible in FIG. 4 so as to cover these edge portions and the electrically conductive screws 204 - 1 a through 204 - 1 g and 204 - 2 a through 204 - 2 g.
Referring to FIG. 5 , an alternative construction is shown. To further attenuate any RF which might escape through the seams between two panels assembled, for example, in accordance with FIG. 3 , two courses 502 and 503 of panels are utilized. A first course 502 of panels is secured to a stud assembly (per FIG. 1 or FIG. 3 ) using screws 204 . Tape 126 (shown over a seam between screws 204 - 3 and 204 - 4 ) is applied over each seam and also over the heads of countersunk screws in the middles of the second, outer, course of panels as shown in FIG. 5 . In one embodiment tape 126 is omitted from the first course 502 of panels. The second, outer course 503 of panels is secured over the first course 502 . The screws 204 of the second course 503 are at least long enough to penetrate the center layer 110 of the panels of the first, inner, course 502 , thereby providing an electrical connection between the two courses. The first course 502 , having previously been physically and electrically connected to the studs, provides a grounding connection for the second course 503 . In one embodiment, the screws 204 of the second course are long enough to also make a direct electrical connection with the studs 205 - 1 , 205 - 2 and 205 - 2 and to assist in holding both courses on the studs. Conductive tape 126 is applied over the seams of adjacent panels in the second course 503 . In one embodiment tape 126 is omitted.
Alternatively, tape 126 can be applied over all seams of both the first course 502 and the second course 503 if desired. The tape 126 when so applied will be pressed by the compressive forces generated by screws 126 being extended into the underlying studs such that the resulting structure is sufficiently rigid to provide structural integrity and to attenuate if not eliminate all RF transmissions through the wall.
In some embodiments other construction is used instead of studs. For example, the invention may be practiced by placing panels which have wood or other appropriate material for their outer layers upon foam, the foam being over a concrete floor. A foam thickness of ¼ to ½ inch is recommended. The panels are electrically connected to each other using in one embodiment electrically conductive strips of material placed on or in the foam as well as to the walls, all of which are held at a fixed potential, typically ground, thus providing the RF shielding effect. The foam improves the attenuation of sound. Other structures for electrically grounding the floor panels will be obvious to those skilled in the electrical arts.
The center material 110 of each panel may be selected not only for electrical properties but for physical strength as well. For example, a center material made of a certain thickness of sheet steel provides resistance to a blast, bullets, or other projectiles. Such a material also resists secretive drilling of a hole for the insertion of a sensing device, or at least makes such a penetration obvious upon inspection.
The laminated structure described provides a panel which may be handled by two people. Depending upon the material selected for center layer 110 , the panel may be cut with a conventional circular saw using blades intended for cutting wood. An RF attenuating room constructed using panels produced by practicing the invention is easier to construct and enjoys a lower total cost than equivalent solutions available today.
The laminated structure of the invention is consistent with some embodiments of the invention disclosed in U.S. patent application Ser. No. 10/658,814. Accordingly, panels constructed according to the present invention will attenuate sound as described in application Ser. No. 10/658,814.
Table 1 shows the estimated RF and acoustic attenuation provided by enclosures constructed using panels constructed in accordance with the present invention.
TABLE 1
Acoustic
Acoustic
Standard
standard
Assembly
Achieved using
achieved using
method of room
RF attenuation
single studs
double studs
Single layer
up to 95 dB
STC 54
STC 66
of panels for
walls, ceiling
and floor
Double
up to 120 dB
STC 60
STC 74
overlapping
panels for
walls, ceiling
and floor
Panels constructed in accordance with the present invention, using a minimum 0.011 inch thick steel plate for center material 110 , are believed to be compliant with DCID6/9.
While the invention has been described in conjunction with complete panels as manufactured at the plant, in practice, panels will have to be cut on site to fit the particular sizes intended to be covered. When this is done, tape will not exist on the edge on the panel which is exposed by the cut. While FIG. 2 , described above, shows one solution to this problem, another solution is shown in FIG. 7 . As shown in FIG. 7 , a conductive cord 127 fabricated of a mixture of butyl and nickel-coated carbon slivers or nickel filings inserted into the butyl up to about 80% by weight, is placed on the exposed metal edge of the internal electrically-conductive metal layer 110 in the panel. Once the butyl cord containing adequate conductive filings has been placed over the edge, a conductive tape 122 can then be placed over both the butyl cord and the remainder of the edge exposed by the cut. Each conductive tape 122 has one or two edge portions such as portions 122 - 1 and 122 - 3 which extend beyond the panel edge and thus can be folded over onto the adjacent portions of the surfaces of the panel. When two panels so cut are then abutted against each other as shown in FIG. 7 (the space between the panels and the conductive tapes 122 on the edges of the panels is exaggerated for illustrative purposes) then a third conductive tape 126 can be placed over the seam between the panels 100 - 1 and 100 - 2 to electrically contact the bent edges 122 - 3 and 122 - 4 of the conductive tape on the edges thereby to ensure that the entire structure is at a fixed potential such as electrical ground. Such a structure then is highly effective in preventing the transmission of RF signals.
The conductive cord has been found by experiment to require approximately 80% by weight of the conductive metal filings such as conductive nickel filings or nickel-coated carbon slivers in order to be electrically conductive and thereby ensure that the internal electrically conductive metal layer 110 is at approximately the same potential (preferably ground) as the electrically conductive tape 122 . Other electrically-conductive metals can also be used, if desired, in cord 127 . As a result, the invention is capable of being used with cut panels as well as with prefabricated panels having the conductive tape already in contact with the internal electrically conductive layer 110 . As described above, a portion of the edge-connected conductive tape will extend beyond the panel for ease of electrical contact.
The effectiveness of this invention in reducing the transmission of RF signals through walls is shown in FIGS. 6A through 6H . FIGS. 6A through 6H show the attenuation as a function of frequency of the RF signal varying from 19 MHz to 10 GHz for different structures identified at the top of each figure. Thus, FIG. 6A shows the attenuation for a laminated panel with no seams and horizontal antenna polarity to range from 80 dB at approximately 20 MHz to 100 dB just below 200 MHz and then dropping to between 60 to 70 dB at 1 GHz. Beyond 1 GHz the attenuation is shown to be relatively flat with negative and positive spikes as a function of frequency.
FIG. 6B shows the attenuation for a laminated panel with no seams and vertical antenna polarity. The attenuation varies from approximately 76 dB at 20 MHz to as high as over 100 dB in the range of 100 MHz to about 180 MHz dropping in a spike back to 80 dB at 200 MHz and then remaining between 90 and 110 dB until approximately 800 MHz thereafter dropping to approximately 70 dB between 1 GHz and 10 GHz.
FIG. 6C shows the RF signal attenuation for a laminated panel with a seam along the manufactured panel edges and horizontal antenna polarity. This structure shows attenuation varying from a little better than 80 dB at 20 MHz down to about 40 dB in the range of about 4½ GHz to 7 GHz.
FIG. 6D shows the RF signal attenuation for a laminated panel with a seam along the manufactured panel edges with a vertical antenna polarity which has the attenuation varying from a little over 70 dB at 20 MHz to approximately 80 to 90 dB in the range of 100-200 MHz and then dropping to approximately between 50 dB and 60 dB in the 1 GHz to 10 GHz range.
FIG. 6E shows the RF signal attenuation for a laminated panel with the seam along field modified panel edges and horizontal antenna polarity. The attenuation varies from between 50 dB and 60 dB for a frequency of 20 MHz to as high as 90 dB for a frequency of 200 MHz and then drops to a value of approximately 35 dB attenuation for 2 GHz climbing to approximately 70 dB attenuation for between 9 GHz and 10 GHz.
FIG. 6F shows the RF signal attenuation associated with a laminated panel with a seam along field modified panel edges and vertical antenna polarity. The attenuation varies from 70 dB at 20 MHz to as high as 100 dB at approximately 200 MHz and then drops with certain spikes to as low as approximately 43 dB between 3 and 4 GHz.
FIG. 6G shows the RF signal attenuation associated with a two-layer system of laminated panels, one continuous and one with a seam along field modified panel edges and with horizontal antenna polarity. The attenuation is shown to be much better using this structure than in some of the previous structures, varying from approximately 89 dB attenuation at 20 MHz to as high as 120 dB at 300 MHz and dropping to between 50 dB and 60 dB in the range of 2 GHz to 3 GHz and then rising again to approximately 82 dB or 83 dB at 10 GHz.
FIG. 6H shows the RF signal attenuation associated with a two-layer system of laminated panels structured in accordance with this invention, one a continuous panel covering a seam in an underlying layer of panels created by abutting two field modified panel edges (such as shown in FIGS. 2 and 7 ) using vertical antenna polarity. The attenuation varies from about 77 dB at 20 MHz up to a peak of between 105 to 120+ dB at approximately 150 mHz to 170 MHz with some gradual drop to within the range of 52 dB to 70 dB for signals with a frequency of 1 GHz to 10 GHz.
As can be seen from FIGS. 6A to 6H , the structure of this invention significantly attenuates RF signals in frequency ranges commonly used with many types of communication systems.
The present disclosure is to be taken as illustrative rather than as limiting the scope, nature, or spirit of the subject matter claimed below. Numerous modifications and variations will become apparent to those skilled in the art after studying the disclosure, including use of equivalent functional and/or structural substitutes for elements described herein, and/or use of equivalent functional steps for steps described herein. Such variations are to be considered within the scope of what is contemplated here. For example, while the described structures are shown as rectangular in shape, structures with other shapes, such as circular, hexagonal or other polygonal shapes can also be used, if required or appropriate. This invention is not limited to any particular shape.
Thus the invention is not limited to the embodiments described above.
The following claims are not to be taken as limiting Applicant's right to claim disclosed, but not yet literally claimed subject matter by way of one or more further applications including those filed pursuant to 35 U.S.C. §120 and/or 35 U.S.C. §251.
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An improved radio frequency wave attenuating wall (ceiling or floor) or door material comprises a laminated structure having as an integral part thereof one or more layers of a viscoelastic material which also functions as a glue and one or more electrically conducting layers. An electrically conducting material such as tape or a formed metal channel provides an electrical connection between the electrically conducting material and an exposed outer surface of the laminated structure. In one embodiment the electrically conducting material is paint. In one embodiment, standard wallboard, typically gypsum, comprises the external surfaces of the laminated structure and one or more conductive layers are constructed between the gypsum exterior. In one embodiment, the conducting layer material is selected to provide physical security in addition to radio frequency wave attenuation. The construction is such that acoustical attenuation is also achieved.
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FIELD OF THE INVENTION
[0001] The present invention relates to a fitting for a tube, especially for braking systems.
BACKGROUND OF THE INVENTION
[0002] Fittings for tubes according to the preamble of claim 1 are already known of. Such fittings are known as rapid or super rapid fittings.
[0003] In the braking system sector, especially for heavy vehicles, for reasons of safety, tubes which cannot be extracted from a connection except by an authorised person, are required. As a result, such fittings have a component which blocks the tube that, rather than being possible to manoeuvre by hand as in traditional fittings, is a specific element that can only be manoeuvred through use of a specific tool available to authorised staff.
SUMMARY OF THE INVENTION
[0004] The purpose of the present invention is to propose a fitting making it possible to satisfy such requisite of improved security but which, at the same time, uses traditional components.
[0005] Such purpose is achieved by a fitting comprising an external body and a caliper element lodged in an axial cavity of said body and able to block the end of the tube inside said cavity. The caliper element can be shifted from a rearward position blocking the tube to a forward position releasing the tube, and comprises a flanged rim on which the axial force used to shift the caliper into said forwarded release position can be exerted. The flanged rim of the caliper is surrounded by an external security ring portion able to resist at least any axial force exerted manually, said external ring portion being positioned in such a way as to allow access to the flanged rim only by means of a special tool.
[0006] In accordance with a particularly advantageous embodiment, the external security ring portion terminates in a narrowed protecting portion, axially distant from and aligned with the flanged rim of the caliper element. Such protecting portion is flexibly yielding if subjected to said axial force exerted manually, so as to be able to be shifted axially into contact with said flanged rim. The external and protecting portions are reciprocally positioned so as to make pressure solely on the innermost portion possible only by use of the special tool.
[0007] The external security ring portion which surrounds the flanged rim of the caliper element thus prevents access to the latter, except by means of a special tool of such thickness as to engage the flanged rim only, but not the external ring portion. The protecting portion makes it possible to prevent, at the moment of insertion of the tube in fitting, the passage of foreign bodies such as dirt, dust or oil, inside the fitting.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] Further features and advantages of the fitting according to the present invention will be evident from the description below, made by way of an indicative and non-limiting example of its preferred embodiments, with reference to the attached figures wherein:
[0009] FIG. 1 shows an exploded view of a fitting according to the invention, in a first embodiment;
[0010] FIG. 2 shows the same exploded view, but in an axial cross-section;
[0011] FIG. 3 shows the assembled fitting in partial axial cross-section;
[0012] FIG. 4 shows, in cross-section, the fitting with a tube inserted and a manoeuvring tool in an idle position;
[0013] FIG. 4 a shows an enlarged detail of FIG. 4 ;
[0014] FIG. 5 shows, in cross-section, the fitting with a tube inserted and the manoeuvring tool in an active position releasing the tube;
[0015] FIG. 6 shows an exploded view of a fitting according to the invention, in an embodiment variation;
[0016] FIG. 7 shows the same exploded view but in axial cross-section;
[0017] FIG. 8 shows in partial axial cross-section, the assembled fitting;
[0018] FIG. 9 shows, in cross-section, the fitting with a tube inserted and the manoeuvring tool in an idle position; and
[0019] FIG. 10 shows, in cross-section, the fitting with a tube inserted and the manoeuvring tool in an active position releasing the tube.
DETAILED DESCRIPTION OF THE INVENTION
[0020] With reference to FIGS. 1-5 , reference numeral globally denotes a rapid fitting according to the invention in a first embodiment. The fitting 1 is able to fluidically connect a tube 2 to a fluid collection body—not shown.
[0021] The fitting 1 comprises an external body 10 which extends axially from an inlet portion 13 , which the tube 2 is inserted into, to an outlet portion 14 , suitable for joining to the fluid collector body. To form such coupling, the outlet portion 14 has, for example, a threaded portion 15 .
[0022] The body 10 defines internally an axial cavity 12 .
[0023] In the body 10 , a first annular shoulder 16 is formed which a sealing element, such as an o-ring 18 rests on.
[0024] According to one embodiment, a second annular shoulder 20 is formed inside the body 10 which a guide sleeve 22 for the end of the tube 2 inserted in the fitting 1 rests on, on the opposite side to that on which it is attached to the collector body.
[0025] A caliper element 24 is seated in the body 10 for blocking the end of the tube 2 in the fitting 1 .
[0026] The caliper element 24 is comprises an essentially cylindrical body 25 at the end of which a number of biting teeth 26 are provided, individuated by notches 27 directed according to the generators of the cylindrical body. Each of said teeth 26 has a conical external surface 26 ′ which tends to widen radially towards the end, and pointed portions 28 facing inwards radially, able to interact with the external surface of the tube 2 . Each tooth 26 terminates moreover in a countersunk surface at the end 29 able to interact with the sealing element 18 , as will be explained better below.
[0027] On the side opposite the teeth 26 , the body 25 of the caliper element terminates in a flanged rim 30 which protrudes from the inlet portion 13 of the body 10 .
[0028] Internally, the body 10 of the fitting 1 also has an annular projection 32 protruding radially inwards and able to interact with the external conical surface 26 ′ of the teeth 26 , when the element is in the blocked position, as will be illustrated below.
[0029] Normally, or following the insertion of the end of the tube 2 in the caliper element, the latter finds itself in an idle position, in which the biting teeth 26 are found beyond the annular ridge 32 (in relation to the direction of insertion of the tube) of the body 10 . The tube, advancing in the caliper element 24 , widens the teeth 26 and hits against the rim of the guide sleeve 22 resting on the second shoulder 20 .
[0030] Simple pulling of the tube backwards and/or the onset of the pressure of the fluid inside the fitting provokes a backward movement of the tube 2 and therefore an interaction of the pointed portions 28 of the teeth 26 with the surface of the tube. The caliper element 24 too tends therefore to move backwards, until the annular projection ridge 32 in the body 10 engages the external surface 26 ′ of the teeth 26 , pushing them radially and forcing them to bite the tube more strongly. In this position, the tube 2 remains firmly inserted in the fitting.
[0031] The fitting 1 also comprises a security ring 40 fitted onto the body 10 of the fitting.
[0032] The security ring 40 comprises a cylindrical portion 42 fitted onto the body 10 , near the input end 13 and extending axially from such end of the body 10 . Said cylindrical portion 42 therefore has a bigger internal diameter than that of the tube 2 , for example equal to the external diameter of the flanged rim 30 of the caliper element 24 .
[0033] The security ring 40 terminates, on the part opposite the body 10 , narrowing into an annular protecting portion 44 able to embrace, making contact with the same, the outer surface of the tube 2 . In other words, the internal diameter of said annular portion is equal to the external diameter of the tube 2 . Consequently, the annular portion 44 is essentially axially aligned to the flanged rim 30 of the caliper element 24 .
[0034] The cylindrical portion 42 and the annular portion 44 are joined by an intermediate portion 46 . Preferably, such intermediate portion 46 extends in a radial direction, that is perpendicularly to the main axis of the fitting 1 .
[0035] Advantageously, moreover, the annular portion 44 terminates with an inner countersunk surface 44 ′, so as to facilitate the insertion of the tube 2 into the security ring.
[0036] The cylindrical portion 42 of the ring 40 has the characteristic of not being deformable axially if subjected to an axial force exerted with a person's hand. Such function may be obtained by choosing a suitable material and/or appropriate thickness for the cylindrical portion 42 .
[0037] In addition, advantageously, the resistance to axial deformation of the cylindrical portion 42 is further accentuated by the fact that it rests, at least in part of its transversal cross-section, on the annular rim 13 ′ defining the inlet of the body 10 .
[0038] The intermediate portion 46 , rather, has the characteristic of being flexibly yielding if subjected to such axial force. In other words, an axial force, exerted that is to say along the main axis of the fitting, applied to the intermediate portion 46 and/or the annular portion 44 , causes the bending of such intermediate portion 46 as a result bringing the annular portion 44 closer to the flanged rim 30 of the caliper element 24 .
[0039] Upon cessation of the axial pressure, the intermediate portion 46 and thus the annular portion 44 connected to it return to their original position.
[0040] Such elastic yielding function may be absolved by choosing a suitable material and/or reduced thickness for the intermediate portion 46 .
[0041] It should be noted that the radial extension of the intermediate portion 46 and of the annular portion 44 is such that once the tube has been inserted in the fitting 1 through the security ring 40 , it is not possible to press the intermediate portion and/or annular portion 44 with the fingers without acting on the cylindrical portion 42 too. The result is that the intermediate portion 46 cannot be bent axially and consequently nor can the annular portion 44 be made to advance axially towards the caliper element 24 .
[0042] By acting rather with a “localised” pressure on the intermediate portion 46 and/or the annular portion 44 only, with the same force applied one can achieve such axial shifting of the annular portion 44 .
[0043] The length or axial extension of the security ring 40 is chosen so that the axial shift of the annular portion 44 which can be obtained by operating in a manual but localised manner makes it possible to bring said annular portion 44 into contact with the flanged rim 30 of the caliper element, so as to transmit the pressure exerted to the latter.
[0044] For the realisation of the security ring 40 advantageously a polymer, natural or synthetic shape memory material may be used at least for the intermediate and annular 44 portions. The different rigidity between the cylindrical portion and the intermediate portion may be obtained by a different cross-linking of the polymer and/or by giving different thicknesses to the two parts, as shown in the example illustrated.
[0045] According to an embodiment variation of the fitting 100 illustrated in FIGS. 6-10 , wherein the elements of the fitting common to the first embodiment have been indicated with the same reference numerals, the flanged rim 30 of the caliper element 24 is surrounded by an external annular security portion 420 obtained as an extension of the inlet portion 13 of the body 10 of the fitting which terminates at least at the height of the flanged rim 30 , preferably beyond said rim, as in the example shown. Once a tube 2 has been inserted in the fitting, such external annular portion 420 prevents access to the flanged rim 30 with the fingers, making the use of tool specially designed for releasing the tube necessary.
[0046] Advantageously, at the inlet portion 13 of the body which surrounds the flanged rim 30 of the caliper element a protective cap 421 is fitted which comprises an external cylindrical portion 422 , which envelops said inlet portion 13 , and which terminates narrowing to an annular portion of protecting 440 axially distanced from and aligned with the flanged rim 30 . Such annular protecting portion 440 is able to embrace the outer surface of the tube 2 , being in contact with it when inserted in the fitting. Advantageously, moreover, the annular protecting portion 440 terminates with a countersunk inner surface 440 ′, so as to facilitate insertion of the tube 2 .
[0047] The annular protecting portion 440 is joined to the external cylindrical portion 422 by an intermediate portion 460 . Preferably, such intermediate portion 460 extends in a radial direction, that is, perpendicularly to the main axis of the fitting 100 .
[0048] The intermediate portion 460 , rather, has the characteristic of being flexibly yielding if subjected to axial force exerted manually. In other words, an axial force, exerted that is to say along the main axis of the fitting, applied to the intermediate portion 460 and/or the annular portion 440 , causes the bending of such intermediate portion 460 as a result bringing the annular portion 440 closer to flanged rim 30 of the caliper element 24 . ( FIG. 10 ).
[0049] Upon cessation of the axial pressure, the intermediate portion 460 and thus the annular portion 440 connected to it return to their original position.
[0050] Such elastic yielding function may be absolved by choosing a suitable material and/or reduced thickness for the intermediate portion 460 .
[0051] In this case too, the radial extension of the intermediate portion 460 and of the annular portion 440 is such that, once the tube 2 has been inserted in the fitting 1 , it is not possible to press the intermediate portion 460 and/or the annular portion 440 with the fingers without also acting on the cylindrical extension 420 of the end 13 of the body 10 .
[0052] In other words, the embodiment variation of the fitting illustrated in FIGS. 6-10 differs from the form of embodiment shown in FIGS. 1-5 by the fact that the cylindrical portion 42 of the security ring 40 is replaced by the extension 420 of the inlet portion 13 of the body 10 . In the embodiment variation, therefore, the cylindrical portion 422 of the protective cap 421 has the main function of coupling to the body 10 and acting as a support to the yielding portion 460 and the annular protecting portion 440 .
[0053] According to one embodiment, near the inlet portion 13 , the body 10 is fitted on its outer surface with a cuneiform annular tooth 50 able to facilitate the application of the security ring 40 or protective cap 421 to the body 10 and to prevent accidental slipping off.
[0054] The present invention also relates to a tool 60 able to exert localised pressure on the annular protecting portion 44 ; 440 of the security ring or protective cap respectively.
[0055] According to one embodiment, such tool 60 can be rapidly coupled to the tube 2 . For example the tool 60 has a “C”-shaped transversal cross-section so as to be geometrically and firmly coupled to the tube 2 .
[0056] The tool 60 comprises a flanged portion head 61 , able to be engaged manually by an operator, and a collar 62 extending from said head portion 61 and which, when the tool 60 is joined to the tube 2 , adheres to it and faces the fitting.
[0057] The collar 62 is of a thickness more or less equal to that of the annular protecting portion 44 ; 440 , so that however much the tool is pressed into contact with said ring the collar acts solely on the internal annular portion 44 ; 440 , or at most also on the intermediate portion 46 ; 460 .
[0058] The tool 60 therefore acts as an adaptor or reducer element to concentrate the force exerted by the operator on the head portion 60 of a circumference, or in any case on an annular surface of a thickness essentially equal to that of the annular portion 44 ; 440 .
[0059] FIGS. 4 , 9 show the fitting 1 with the tool 60 connected to the tube 2 but in a distanced position from the annular protecting portion 44 ; 440 .
[0060] FIGS. 5 , 10 show the tool 60 in pressure on the annular portion 44 ; 440 . As anticipated above, in this condition an operator is able, with the tool 60 , to act on the annular portion 44 ; 440 and therefore on the flanged rim 30 of the caliper element 24 , pushing it into a forward position in which the tube is released. In such forward position, the biting teeth 26 disengage from the annular ridge 32 and, thanks also to the cone-shaped surface of the end 29 of said teeth and the sealing element 18 , distanced sufficiently to enable the disengagement of the pointed portions 28 from the surface of the tube 2 , and therefore the extraction of the same from the fitting.
[0061] It should be noted that this operation requires a force exerted by the operator similar to the force that direct action on the caliper element of a traditional fitting would require.
[0062] Advantageously, the security ring 40 can be fitted onto a fitting 1 having a body 10 and a caliper element 24 of the known type. In other words, this application does not require the supplier of couplings to produce and deal in specific fittings.
[0063] A further, non-secondary aspect of the fitting which the present invention relates to is that the annular protecting portions 44 , 440 of the security ring 40 and protective cap 421 perform an important function of protecting the fitting from dirt, dust or other agents which might get into it.
[0064] In fact, if the tube 2 is not clean, when it is inserted in the security ring 40 or in the protective cap 421 the outer surface of the end which goes into the fitting is cleaned by contact with the annular portion 44 ; 440 of the security ring or protective cap.
[0065] A man skilled in the may make modifications, adjustments and replacements of elements with others functionally equivalent to the fitting described above so as to satisfy contingent requirements, while remaining within the scope of the following claims. Each of the characteristics described as belonging to a possible embodiment may be realised independently of the other embodiments described.
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A fitting has an external body and a caliper element, lodged in an axial cavity of the body and able to block the end of a tube inside the cavity. The caliper element can be moved from a rearward position blocking the tube, to a forward position releasing the tube, and includes a flanged rim protruding from an end of the body. A security ring is joined to the end of the body from which the flanged rim protrudes. The ring has an outer portion which extend axially from the end and can resist at least an axial force exerted manually, and an innermost portion which is flexible so that when subjected to an axial force exerted manually, it can move axially and to touch the flanged rim. The inner and outer portions are reciprocally positioned so pressure can be exerted on the innermost portion only with a special tool.
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BACKGROUND OF THE INVENTION
1. Technical Field
The present invention relates generally to devices used to sort laundry prior to washing, especially such devices that have several compartments for different types of items to be laundered.
2. Background Information
Clothes hampers, used for the storage of soiled laundry, are very old and well known. More recently, others have developed devices for separating laundry of different types in different compartments. For example, colored laundry is separated from whites, or polyester from cotton.
However, a number of shortcomings have been found with these devices. For example, typical hampers have solid walls that restrict air flow on the sides and bottom, and frequently on the top as well. Thus, damp clothing items left in such a hamper are not likely to be exposed to the air, and may therefore attract mold and mildew, which may also affect other items in contact with the damp item.
Furthermore, typical hampers or clothes sorters are only accessible from one location, usually the top of the storage compartment. Such a limitation on accessibility is frequently very inconvenient, and also places limitations on where in a room the clothes hamper may be placed. In particular, the hamper will usually have to be placed on the floor, and floor space is frequently at a premium in the laundry areas of many residences.
The multiple compartment laundry sorter of the present invention overcomes difficulties described above and affords other features and advantages heretofore not available.
SUMMARY OF THE INVENTION
The multiple compartment laundry sorter of the present invention provides easy access to several storage areas, and the ability to position the unit in several locations. It preferably includes walls and dividers made of a material having an open mesh pattern to permit air circulation through the stored laundry items. The material is suspended from or attached to a frame that may be hung from a ceiling or wall. Alternatively, rollers or wheels may be attached to the frame for portable floor mounting.
It is an object of this invention to provide a laundry sorter for separating soiled laundry by various criteria, such as color, fabric or washing cycle, into a multiplicity of compartments. It is a further object of this invention to provide a laundry sorter that is easily accessible from at least two locations, providing access to each of the multiple compartments with equal ease and reliability. It is a further object of this invention that the material used to form the walls of the multiple compartments provide thorough ventilation to the contents thereof. This ventilation preferably is enhanced by the configuration of the compartments. It is a further object of this invention that the laundry sorter may be mounted in an elevated position for efficient use of the limited space available in the typical laundry room. Finally, it is also an object of this invention that the laundry sorter may be easily fabricated of readily available materials, rendering it inexpensive to manufacture and sell.
Other objects and advantages of the invention will become apparent from the following detailed description and from the appended drawings in which like numbers have been used to describe like parts throughout the several views.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front perspective view of a preferred embodiment of the multiple compartment laundry sorter of the present invention;
FIG. 2 is a top view of the multiple compartment laundry sorter;
FIG. 3 is a front view of a second embodiment of the multiple compartment laundry sorter;
FIG. 4 is a right side view of the multiple compartment laundry sorter illustrated in FIG. 3;
FIG. 5 is a right side view of a third embodiment of the multiple compartment laundry sorter;
FIG. 6 is a rear perspective view of a fourth embodiment of the multiple compartment laundry sorter;
FIG. 7 is an exploded perspective view of the frame of the multiple compartment laundry sorter; and
FIG. 8 is a section view of the frame of the multiple compartment laundry sorter taken along line 8--8 of FIG. 2.
DESCRIPTION OF THE PREFERRED EMBODIMENT
With reference to the drawings, and in particular to FIG. 1, the multiple compartment laundry sorter is generally indicated by reference numeral 10. Laundry sorter 10 includes a support frame 12 and a rear wall 14. Preferably, a sheet of plastic mesh 16 or other perforated material is used to divide the multiple compartments C. A sheet of plastic mesh 16 or other perforated material is also used for the rear wall 14. As may be seen in FIGS. 1 and 2, compartments C may vary in width, although their depth will generally remain constant, preferably the width of a sheet of plastic mesh 16.
Referring to FIGS. 2, 7 and 8, support frame 12 preferably includes square tubing sections 18 and 18A along the front and rear sides, respectively, of laundry sorter 10. Tubing section 18A defines the top side of rear wall 14. Extending between tubing sections 18 and preferably welded thereto are round lateral tubing sections 20, 20A and 20B. Tubing sections 20 define the top sides of intermediate wall members 21, and tubing sections 20A and 20B define the top sides of end wall members 19 and 23, respectively. Square tubing sections 18, 18A and round tubing sections 20, 20A and 20B are preferably metal, but may alternatively be made of plastic or wood. The bottoms of compartments C are defined by a floor wall member 25. In the preferred embodiment, floor wall member 25 is simply the lower portion of plastic mesh 16 suspended from tubing sections 20, 20A and 20B. As shown in FIG. 8, a single long sheet of plastic mesh 16 is preferably used to form the dividing and supporting surfaces of the multiple compartments C. The sheet of plastic mesh 16 is wound over lateral support tubes 20, and generally retained in position by retaining ties 22, which interlock with mesh 16 of rear wall 14. Retaining ties 22 preferably are commonly available wire ties. As shown in FIG. 2, the sheet of plastic mesh 16 is attached to lateral tubing sections 20 with retaining clips 24. Retaining clips 24 preferably are commonly available ratchet-type pinch clips. Retaining clips 24 preferably are spaced along lateral tubing sections 20 approximately every four to six inches.
As shown in FIG. 1 the basic configuration of laundry sorter 10 may be easily adapted to be suspended from a ceiling, as over a clothes washing machine W and dryer D. Alternatively, as shown in FIGS. 3 and 4, the addition of a support stand 26 to laundry sorter 10 permits positioning over clothes washing machine W and dryer D. Support stand 26 preferably includes legs 28, rear cross bracing 30 and side cross bracing 32. As shown in FIG. 7, support stand 26 may be attached to support frame 12 of the suspended embodiment illustrated in FIG. 1. To do so, an adaptor 34 is fixedly attached as by welding to the upper end of leg 28. Adaptor 34 includes a reduced portion 36 that may be slidably received within the open end of tubing section 18. Tubing section 18 and reduced portion 36 of adaptor 34 each include holes 38 that may be aligned for receiving a threaded eye bolt 40, which may be fixed in position with nuts 42. For added support, a strengthening flange 44 is preferably fixedly attached, as by welding, to the intersection of leg 28 and adaptor 34. In the embodiment illustrated in FIGS. 3 and 4, regular hex-head bolts may be substituted for eye bolts 40 if laundry sorter 10 will not be suspended from a ceiling as illustrated in FIG. 1.
As shown in FIG. 5, a mounting frame 46 may alternatively be attached to laundry sorter 10 for attachment to a wall. Mounting frame 46 includes front vertical support members 48, lower horizontal support members 50, rear vertical mounting members 52 and side cross bracing 54. Front and rear vertical mounting members 48, 52, respectively, attach to square tubing sections 18 in the same fashion as illustrated in FIG. 7.
Finally, as shown in FIG. 6, another alternative arrangement of laundry sorter 10 includes the addition of a rolling frame 56 for easy moving on a floor or other flat surface. Rolling frame 56 includes four legs 58, rear cross bracing 60, left and right lower horizontal support members 62, and front and rear lower horizontal support members 64. Attached to the bottom of each leg 58 is a roller 66. Preferably, the embodiment of laundry sorter 10 illustrated in FIG. 6 also includes front doors 68 and an upper horizontal surface 70, also made of plastic mesh 16. As shown in FIG. 6, upper horizontal surface 70 may be used for conveniently drying and storing certain delicate laundry items, such as sweater S.
Referring to FIGS. 1 and 2, while the preferred embodiment is made of flexible plastic mesh 16, it is readily apparent that rigid, perforated plastic materials may be directly substituted for the described components and still fall within the spirit and scope of the invention.
The multiple compartments C may be effectively utilized for sorting and storing different items of laundry. For example, the three relatively large compartments C as shown on the right hand side of the laundry sorter in FIG. 1 may be utilized to receive, respectively, dark clothing items, light colored clothing items, and towels. The two smaller width compartments C shown on the left hand side of the sorter apparatus of FIG. 1 could be utilized, for example, to store red and green colored clothing items, respectively. Additionally, sub-compartments C-1 and C-2 could be formed at the upper end of the two small compartments as shown in the elevation view of FIG. 3. In that embodiment, the sub-compartments C-1 and C-2 are simply formed by providing separate, mesh bottom walls 27 which are attached to the side walls of mesh material 16 defining the two small end compartments. Alternatively, such shorter height sub-compartments could be formed by simply hanging separate mesh fabric material inside of the mesh 16 side walls already in place and suspended from the support bars or tubing sections 20, 20A and 20B. The relatively short height sub-compartments C-1 and C-2 could be advantageously used for sorting and receiving extreme Delicates, such as items of women's underclothing, sweaters and special blouses which might be made of silk or rayon.
While the preferred embodiments of the invention have been described, it should be understood that various changes, adaptations and modifications may be made therein without departing from the spirit of the invention and the scope of the appended claims.
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The multiple compartment laundry sorter of the present invention provides easy access to several storage areas, and the ability to position the unit in several locations. It preferably includes walls and dividers made of a material having an open mesh pattern to permit air circulation through the stored laundry items. The material is suspended from or attached to a frame that may be hung from a ceiling or wall. Alternatively, rollers or wheels may be attached to the frame for portable floor mounting.
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RELATED APPLICATION
This application is a divisional application of U.S. patent application Ser. No. 11/323,111 filed Dec. 30, 2005 now U.S. Pat. No. 7,617,424.
TECHNICAL FIELD
Embodiments of the invention relate to a physical layer interface of a computing system. More particularly, embodiments of the invention relate to error monitoring for serial links between components of a computing system.
BACKGROUND
In computing systems, as operating frequencies increase external testing of physical links becomes increasingly difficult. Some physical link specifications incorporate self-test hooks that can be used to collect, for example, eye diagrams, equivalent time oscilloscope traces and/or bit error rate diagrams. However, these self-test hooks may be sufficiently inflexible, which may result in a complex and/or time consuming testing and debugging process.
BRIEF DESCRIPTION OF THE DRAWINGS
Embodiments of the invention are illustrated by way of example, and not by way of limitation, in the figures of the accompanying drawings in which like reference numerals refer to similar elements.
FIG. 1 is a block diagram of one embodiment of an apparatus for a physical interconnect.
FIG. 2 is a conceptual illustration of one embodiment of a system that may utilize point-to-point interconnects.
FIG. 3 is a block diagram of one embodiment of a flexible error counting architecture.
FIG. 4 a is a conceptual illustration of error checking using a single register for each bit of an incoming data stream.
FIG. 4 b is a conceptual illustration of error checking using two registers for alternating bits of an incoming data stream to be stored in respective registers.
FIG. 5 is a conceptual illustration of error checking using multiple registers for selected bits of an incoming data stream to be stored in respective registers.
FIG. 6 is a block diagram of one embodiment of circuitry for error checking using selected bits from incoming data streams.
DETAILED DESCRIPTION
In the following description, numerous specific details are set forth. However, embodiments of the invention may be practiced without these specific details. In other instances, well-known circuits, structures and techniques have not been shown in detail in order not to obscure the understanding of this description.
In one embodiment, pattern generation and comparison may be utilized for error checking purposes. As described in greater detail below, flexibility in the error checking functionality may be provided to enable targeted, hardware specific testing and generic tools such as an “on-die oscilloscope.” Programmable offsets and intervals in the error checking mechanism may allow support of targeted tests and on-die oscilloscope functionality.
In order to adequately characterize error rates on a high-speed serial link, measurements may be taken over a range of frequencies, timing and/or voltage stress factors. At the high end of frequency and stress, large counters may be required to measure the expected error rate. At the low end of frequency and stress, smaller counters may be used because the error rate may be lower. However, simply utilizing large counters to support a full range of testing may be relatively expensive in terms of circuit size and/or power consumption.
As described in greater detail below, in one embodiment, individual counters may be used for individual data lanes. Multiple individual counters may be multiplexed to provide an extended counter for a selected data lane. This extended error counting functionality may allow flexibility to characterize high bit error rates for a selected data lane.
FIG. 1 is a block diagram of one embodiment of an apparatus for a physical interconnect. In one aspect, the apparatus depicts a physical layer for a cache-coherent, link-based interconnect scheme for a processor, chipset, and/or IO bridge components. For example, the physical interconnect may be performed by each physical layer of an integrated device. The physical interconnect may support training and testing in association with use of an oscilloscope probe or other test equipment to monitor the physical interconnect.
Specifically, the physical layer may provide communication between two ports over a physical interconnect comprising two uni-directional links. Specifically, one uni-directional link 104 from a first transmit port 150 of a first integrated device to a first receiver port 150 of a second integrated device. Likewise, a second uni-directional link 106 from a first transmit port 150 of the second integrated device to a first receiver port 150 of the first integrated device. However, the claimed subject matter is not limited to two uni-directional links.
FIG. 2 is a conceptual illustration of one embodiment of a system that may utilize point-to-point interconnects. In one embodiment, the system of FIG. 2 may utilize a point-to-point architecture that supports a layered protocol scheme. In one embodiment, the system may include a plurality of caching agents and home agents coupled to a network fabric. For example, the network fabric may adhere to a layered protocol scheme and comprised of: a physical layer, a link layer, a routing layer, a transport layer and a protocol layer (as depicted in connection with FIG. 1 ). The fabric may facilitate transporting messages from one protocol (home or caching agent) to another protocol for a point-to-point network.
FIG. 2 is a high level, simplified abstraction of a protocol architecture that may utilize one or more point-to-point links. The fabric may facilitate transporting messages from one protocol (caching processor or caching aware memory controller) to another protocol for a point-to-point network. Each caching-aware memory controller may be coupled with memory that may include, for example, dynamic random access memory (DRAM), flash memory, or any other type of memory known in the art.
FIG. 3 is a block diagram of one embodiment of a flexible error counting architecture. In one embodiment, each data lane corresponds to a serial physical link; however, any data communications medium may be utilized. The configuration of FIG. 3 may be used, for example, to count bit errors that occur during transmission of data over a physical link.
In one embodiment, each data line may be coupled with a N-bit counter (e.g., 310 , 312 , 318 ). Any size counter may be used, for example, each counter may be an 8-bit counter. The size of the counter used may be selected based on, for example, the expected error rate for a relatively low end of a frequency, timing and/or voltage stress factors to be used in testing. The N-bit counters may be any size (e.g., 8-bit, 12-bit, 4-bit, 24-bit, 32-bit). Each of the N-bit counters may be coupled with multiplexor 330 .
Control signals may be provided to multiplexor 330 by any type of control circuitry. For example, the control signals may be provided by software controlled circuitry that allows a user to determine the configuration of the counters and multiplexor. In another embodiment, the control signals may be provided by firmware to implement a pre-programmed testing sequence.
The output of multiplexor 330 may be coupled with extended counter 350 . Extended counter 350 may be any size counter (e.g., 24-bit, 32-bit, 16-bit, 8-bit, 56-bit). For example, if N-bit counters 310 , 312 , . . . 318 are 8-bit counters and extended counter 350 is a 24-bit counter, a selected data lane may have 32 bits of error counting. Thus, a single extended counter may be shared between multiple smaller counters to provide a greater error counting capacity than the N-bit counters alone.
In one embodiment, the error count provided by the combination of the selected N-bit counter and extended counter 350 may be accessible through a debug or testability register. In one embodiment, the following register configuration may be used.
TABLE 1 Register configuration. Default Bits Width Name Value Value/Description 31 1 Error 0 If set, indicates that the error counter Overflow has been extended to extended counter. Bit cleared upon Loopback. 30:0 31 Lane Error 0 Lane Error Counter is the accumulation Counter of errors in a selected lane. Exact number of bits in counter may vary by architecture implementation. Counter cleared upon Loopback.
The register configuration of Table 1 corresponds to a total counter (N-bit counter plus extended counter) width of 32 bits. In alternate embodiments, other register configurations may be supported. The register may be accessed in any manner known in the art and the value stored in the register may be used in any manner known in the art.
In one embodiment, a set of testability registers may be used to support targeted tests and/or on-die oscilloscope functionality. In one embodiment, a register may be utilized to store each bit of an incoming data stream. This is conceptually illustrated in FIG. 4 a . While FIGS. 4 a , 4 b and 5 provide examples of 128 bits, any number of bits my be used.
FIG. 4 b is a conceptual illustration of error checking using two registers for alternating bits of an incoming data stream to be stored in respective registers. In one embodiment, error checking circuitry may have multiple fields that may be used to selectively program sample and store incoming data bits to various testability registers. By interleaving bits one receiver may sample, for example, the odd bits while a second receiver may sample the even bits.
In one embodiment, a testing instruction and/or a testing register may include fields that correspond to a start of testing and an offset, or interval, that may indicate the sampling interval. In the example of FIG. 4 b , the first receiver that samples the odd bits may have an offset of “0” and an interval of “2” to indicate that the first bit and every second subsequent bit should be sampled. The second receiver that samples the even bits may have an offset of “1” and an interval of “2” to indicate that the second bit and every second subsequent bit should be sampled. Other offsets and intervals may be used to provide different testing scenarios.
For example, an initial round of testing may be accomplished using a first set of offsets and intervals. This could be, for example, every fourth or every tenth bit. The sampled data may be compared to expected data to determine whether the data appears to be as expected. If so, the test results may be considered satisfactory. If, however, one or more of the bits are not as expected, a different offset and/or interval may be used to provide additional testing information that may be used to debug the underlying system or configuration.
FIG. 5 is a conceptual illustration of error checking using multiple registers for selected bits of an incoming data stream to be stored in respective registers. In one embodiment, each individual bit in a stream of data may be characterized to build an on-die oscilloscope trace. The example of FIG. 5 illustrates a first receiver with offset of “0” and an interval of “128,” a second receiver with an offset of “1” and an interval of “128” and so on. In general, the greater the interval the less inter-symbol interference (ISI) experienced.
The individual bits that are captured using the offset and interval parameters may be combined to generate an on-die oscilloscope trace using suitable techniques known in the art. The techniques and architectures described herein may provide improved raw data from which to generate testing data. Another advantage of the techniques described herein is that, using the offset and interval parameters, the testing process may be more efficient because the granularity of the testing data may be tailored to the specific situation.
FIG. 6 is a block diagram of one embodiment of circuitry for error checking using selected bits from incoming data streams. Multiple receiver circuits (e.g., 610 , 612 , 618 ) may be coupled to receive data via a data lane. The receivers may be coupled with control circuitry 630 , which may cause the receivers to selectively sample data according to offset and interval parameters for the respective receivers, as described above. Control circuitry 630 may be coupled to receive the parameters from an external source, for example, one or more debug or testing registers, a software application, etc.
Comparison circuitry 650 may be coupled with control circuitry 630 to compare the sampled data values to expected data values. The sampled data values may be stored, for example, in registers in the respective receivers and/or in registers in control circuitry 630 . The sampled data values may be accessed in any manner known in the art.
Reference in the specification to “one embodiment” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the invention. The appearances of the phrase “in one embodiment” in various places in the specification are not necessarily all referring to the same embodiment.
While the invention has been described in terms of several embodiments, those skilled in the art will recognize that the invention is not limited to the embodiments described, but can be practiced with modification and alteration within the spirit and scope of the appended claims. The description is thus to be regarded as illustrative instead of limiting.
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Methods, apparatuses and systems for physical link error data capture and analysis. A receiver is coupled to receive a data stream via a point-to-point serial link. A control circuit is coupled with the receiver to cause the receiver to selectively sample the data stream according to an offset parameter and an interval parameter. Comparison circuitry compares the data stream sample to expected data values to determine a bit error rate.
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RELATED APPLICATIONS
[0001] The present application is based on, and claims priority from, Taiwan Application Serial Number 94135384, filed Oct. 11, 2005, the disclosure of which is hereby incorporated by reference herein in its entirety.
BACKGROUND
[0002] 1. Field of Invention
[0003] The present invention relates to a conducting textile and related detecting device. More particularly, the present invention relates to a pressure sensible textile and related pressure sensible device.
[0004] 2. Description of Related Art
[0005] With the prosperity of technology, the conducting textile comprising the conducting wefts and warps and the common weaving fiber has been developed. Integrated with the electronic transmission sensor and switches, the conducting textile may be utilized to construct the electronic sensing units and to apply broadly to the sensing devices, for example, the pressure sensing devices.
[0006] Generally, it is usually required in the structure of the pressure sensible conducting textile in the prior art at least two layers of conducting wefts and warps interlaying to each other. The conducting pressure sensible textile disclosed in U.S. Pat. No. 6,333,736 is one of the examples. Without external pressure, the two layers of the conducting wefts and warps do not contact to each other and there is no current flowing between the two layers of the conducting wefts and warps, due to the insulating fibers between the two layers as a supporting structure. In the contrary, when there is pressure applied on the conducting textile, the two layers of the conducting wefts and warps contact to each other due to the external force, the current hence flow, and the pressure is sensed. However, limited by the circuit design, it is required a structure comprising at least two layers of the conducting wefts and warps for pressure sensing. Therefore, the conventional conducting textile is thicker, and the application of the relative products is limited accordingly.
SUMMARY
[0007] A pressure sensible textile is provided. The pressure sensible textile includes at least a high-resistance conducting area and two groups of low-resistance conducting wefts and warps that intercross each other without contacting to each other. The two groups of low-resistance conducting wefts and warps both contact the high-resistance conducting area.
[0008] According to an embodiment of the present invention, one of the two groups of low-resistance conducting wefts and warps is distributed over a side of the high-resistance conducting area, and another group of low-resistance conducting wefts and warps interweaves above and below the high-resistance conducting area alternately. Besides, a group of low-resistance conducting wefts and warps is grounded to separate the high-resistance conducting area into a coupled of pressure sensible areas to increase the sensitivity of detecting the location and magnitude of the pressure.
[0009] According to another embodiment, the pressure sensible textile can be composed of a plurality of high-resistance conducting areas. A group of low-resistance conducting wefts and warps is directly contacted with each of the plurality of high-resistance conducting areas separately, while another group of low-resistance conducting wefts and warps interweaves above and below the high-resistance conducting area. Besides, an insulating area can be utilized to totally isolate the high-resistance conducting areas in order to increase the sensitivity of detecting the location and magnitude of the pressure.
[0010] The aforementioned high-resistance conducting areas are composed of high-resistance conducting wefts and warps having a specific resistance of 10 2 -10 6 Ω/cm. Some examples of the high-resistance conducting wefts and warps may comprise carbon fibers, stainless steel yarn, cupric ion fibers or other metal-plated fibers. The breaking elongation of the high-resistance conducting wefts and warps is to be greater than 30% for a better elasticity of the pressure sensible textile. A specific resistance of the low-resistance conducting wefts and warps, such as metal conducting lines or metal-plated fibers, is less than 50 Ω/cm.
[0011] According to the embodiments above, the pressure sensible textile of the present invention can determine the location and the magnitude of the pressure source simply by laterally and longitudinally interweaving the low-resistance conducting wefts and warps over the one-layered high-resistance conducting textile, and accompanying by two scanning circuits. Therefore, the thickness and the weight of the pressure sensible textile can be substantially reduced, which improves and extends the application. Some of the examples are the pressure sensible rugs at the front door of stores, the interactive perceptive dolls, the children game carpet, the direction and speed detection carpets while people walk on them, and other various applications.
[0012] These and other features, aspects, and advantages of the present invention will become better understood with reference to the following description, figures, and appended claims.
[0013] It is to be understood that both the foregoing general description and the following detailed description are by examples, and are intended to provide further explanation of the invention as claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention. In the drawings,
[0015] FIG. 1 is a diagram of a pressure sensible textile and the corresponding pressure sensible device according to an embodiment of the present invention is illustrated;
[0016] FIG. 2 is a diagram illustrating the relationship between the specific resistance and the magnitude of the deformation of the high-resistance conducting warps and wefts;
[0017] FIG. 3 is a diagram of the pressure sensible textile and the corresponding pressure sensible device according to another embodiment of the present invention; and
[0018] FIG. 4 is a vertical view of one of the pressure sensible areas 310 in FIG. 3 and an insulating area 320 nearby.
DETAILED DESCRIPTION
[0019] A pressure sensible textile and the pressure sensible device are herein introduced to solve the problems in the prior art.
[0020] Reference will now be made in detail to the present embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers are used in the drawings and the description to refer to the same or like parts.
[0021] For the forgoing reasons, there is a need for a thin and light pressure sensible textile and the pressure sensible device adopting it such that the applicability and the convenience may be improved.
The First Embodiment
[0022] Referring to FIG. 1 , a diagram of a pressure sensible textile and the corresponding pressure sensible device according to an embodiment of the present invention is illustrated.
[0023] In FIG. 1 , the main textile 100 of the pressure sensible textile is composed of the high-resistance conducting wefts and warps. The low-resistance conducting warps 110 and the low-resistance conducting wefts 120 a and 120 b are crisscross distributed over the main textile 100 . The low-resistance conducting warps 110 interweave above and below the main textile 100 , and the low-resistance conducting wefts 120 a and 120 b are fixed at one side of the main textile 100 , for example, fixed at the upper side. The low-resistance conducting warps 110 and the low-resistance conducting wefts 120 a and 120 b do not contact to each other in order to prevent short circuits. The weaving scheme of the main textile 100 may be any conventional weaving scheme. For example, the main textile 100 may be a multi-layered structure made by weaving, or may be a warp-inserted multi-layered structure made by knitting.
[0024] The specific resistance of the aforementioned low-resistance conducting warps 110 and the low-resistance conducting wefts 120 a and 120 b is to be less than 50 Ω/cm for better current conducting. The low-resistance conducting warps 110 and the low-resistance conducting wefts 120 a and 120 b may adopt common metal conducting lines, and preferably, softer metal-plated fibers, such as silver-plated fibers.
[0025] The specific resistance of the aforementioned high-resistance conducting wefts and warps of the main textile 100 is preferably 10 2 -10 6 Ω/cm. Moreover, the aforementioned high-resistance conducting wefts and warps need to be elastic. For example, the breaking elongation is to be greater than 30%. Therefore, the high-resistance conducting wefts and warps can not only maintain the conductivity, but also provide a delicate variation of resistance along with the deformation of the fibers. Hence the sensitivity of the pressure detection is increased. Please refer to FIG. 2 that displays the relation between the specific resistance and the stretching strain for example. When the amount of the stretching strain increases, the specific resistance of the conducting wefts and warps enlarges.
[0026] Some examples of the high-resistance conducting wefts and warps of the present invention are the conducting wefts and warps plated with a conducting layer, such like carbon fibers or cupric ion fibers, and stainless steel blended yarn or silver-plated fiber. Besides, the conducting wefts and warps of the present invention may further be conjugate spun with common weaving fibers with the present conducting wefts and warps located outside the common weaving fibers. For instance, the conducting wefts and warps of the present invention may wrap around the common weaving fibers to form conjugate fibers with a structure of wrapped yarn, while applying beaming in the weaving procedure.
[0027] In FIG. 1 , the low-resistance conducting warps 110 and the low-resistance conducting wefts 120 a are coupled to the vertical scanning circuit 130 and the lateral scanning circuit 140 through the switch 150 and the switch 160 respectively, while the vertical scanning circuit 130 and the lateral scanning circuit 140 are further coupled to the controller 170 respectively. In the pressure sensing duration, the controller 170 outputs control signals to the vertical scanning circuit 130 and the lateral scanning circuit 140 separately in order to repeatedly and alternately control the statuses of the switch 150 of the vertical scanning circuit 130 and the switch 160 of the lateral scanning circuit 140 , such that only one of the two switches 150 and 160 is at the “on” status for the benefit to detecting the location of the pressure source.
[0028] According to the pressure sensible textile provided by the embodiment of the present invention, the principle of the pressure sensation when there are only the low-resistance conducting warps 110 and the low-resistance conducting wefts 120 a, and the vertical scanning circuit 130 and the lateral scanning circuit 140 coupled to the low-resistance conducting warps 110 and the low-resistance conducting wefts 120 a, is briefly described below.
[0029] When there is a pressure source applied on the pressure sensible textile, the main textile 100 will be deformed. Since the main textile 100 is made by the elastic high-resistance conducting wefts and warps, the electric signals of the variation of the specific resistance resulted from the deformation may be transmitted to the nearest low-resistance conducting warp 110 and the nearest low-resistance conducting weft 120 a through the high-resistance conducting wefts and warps. Further, the controller 170 turns on the vertical scanning circuit 130 and the lateral scanning circuit 140 coupled to the aforementioned low-resistance conducting warp 110 and the low-resistance conducting weft 120 a alternately. Hence only the vertical scanning circuit 130 and the lateral scanning circuit 140 which are turned on can transmit the electric signals representing the specific resistance of the main textile 100 to the controller 170 .
[0030] Generally speaking, the electric signals represented the variation of the specific resistance of the main textile 100 of the low-resistance conducting warps 110 and the low-resistance conducting wefts 120 a is bigger while the location is nearer to the pressure source or the magnitude of the pressure source is bigger. Therefore, when the controller 170 receives the electric signals representing the variation of the specific resistance from different low-resistance conducting warps 110 and the low-resistance conducting wefts and warps 120 a in order, the controller 170 is able to detect the location and the magnitude of the pressure source with operation by an internal or external data processing center.
[0031] However, when the area of the main textile 100 is too big, the electric signals represented the pressure may become weak due to the high resistance of the transmission path resulted in the long transmission distance. Therefore, the low-resistance conducting wefts 120 b coupled to the ground line 180 may be utilized to separate the main textile 100 into several areas, such that the electric signals from the pressure source between the two neighboring low-resistance conducting wefts 120 b can only be transmitted out from the low-resistance conducting warps 120 a between them. Any electric signals will vanish when being coupled to the grounded low-resistance conducting wefts 120 b. Hence, no matter where the pressure source is located on the main textile 100 , the transmission range of the resulted electric signals does not exceed the area bounded by two neighboring low-resistance conducting wefts 120 b.
The Second Embodiment
[0032] Please refer to FIG. 3 . FIG. 3 illustrates a diagram of the pressure sensible textile and the corresponding pressure sensible device according to another embodiment of the present invention.
[0033] In FIG. 3 , the structure of the pressure sensible textile is different from the pressure sensible textile displayed in FIG. 1 . In FIG. 3 , the main textile 300 of the pressure sensible textile is composed of the pressure sensible area 310 formed by the high-resistance conducting wefts and warps and the insulating area 320 formed by the common yarn. The low-resistance conducting warps 330 are mainly located below the main textile 300 with a short section located above the pressure sensible area 310 in order to directly contact to the high-resistance conducting wefts and warps of the pressure sensible area 310 . The low-resistance conducting wefts 340 are mainly located above the main textile 300 and directly contact to a side of the pressure sensible area 310 . The materials of the aforementioned high-resistance conducting wefts and warps forming the pressure sensible area 310 , and the materials of the low-resistance conducting warps 330 and the low-resistance conducting wefts 340 , are similar to those described in the first embodiment described above.
[0034] The main textile 300 mentioned above may be a multi-layered structure made by weaving, or may be a warp-inserted multi-layered structure made by knitting. Please refer to FIG. 4 . FIG. 4 illustrates a vertical view of one of the pressure sensible areas 310 in FIG. 3 and an insulating area 320 nearby. The main textile 300 is formed by weaving. As displayed in FIG. 4 , assuming the main textile 300 is made by weaving, the low-resistance conducting warps 330 and the low-resistance conducting wefts 340 can even be integrated into the main textile 300 as a part of the main textile 300 .
[0035] Please refer to FIG. 3 again. The low-resistance conducting warps 330 and the low-resistance conducting wefts 340 are coupled to the vertical scanning circuit 350 and the lateral scanning circuit 360 respectively through the switch 370 and the switch 380 respectively, and the vertical scanning circuit 350 and the lateral scanning circuit 360 are further coupled to the controller 390 . The control method of the vertical scanning circuit 350 and the lateral scanning circuit 360 is similar to the control method of the vertical scanning circuit 130 and the lateral scanning circuit 140 of the pressure sensible textile shown in FIG. 1 . That is, the controller 390 fast and alternately controls the statuses of the switches 370 and 380 , such that there is only one vertical scanning circuit 350 and one lateral scanning circuit 360 are electric conductive. The lateral scanning circuit 360 is further coupled to the ground line 400 to provide a low potential reference voltage of the fast scanning circuit.
[0036] Similar to the principle of the pressure sensible textile in FIG. 1 , when there is an external pressure applied to the pressure sensible textile, the main textile 300 is deformed accordingly and so as the pressure sensible area 310 . However, in FIG. 3 , the pressure sensible areas 310 of the pressure sensible textile are separated by the insulating areas 320 . Hence the electric signals representing the change of the specific resistance caused by the deformation of the pressure sensible area 310 can only be transmitted to the low-resistance conducting warps 330 and the low-resistance conducting wefts 340 coupled to the pressure sensible area 310 that carries the pressure. Further, the low-resistance conducting warps 330 and the low-resistance conducting wefts 340 are coupled to the vertical scanning circuit 350 and the lateral scanning circuit 360 . Therefore, only when the vertical scanning circuit 350 and the lateral scanning circuit 360 coupled to the aforementioned low-resistance conducting warps 330 and the low-resistance conducting wefts 340 are electric conductive, the electric signals represented the variation of the specific resistance can be transmitted to the controller 390 .
[0037] Therefore, when the controller 390 receives the electric signals represented different specific resistances from the low-resistance conducting warps 330 and the low-resistance conducting wefts 340 coupled to the pressure sensible area 310 that carries pressure, the location and the magnitude of the pressure source can be determined precisely through a data processing center inside or outside the controller 390 .
[0038] According to the embodiments above, the pressure sensible textile of the present invention can determine the location and the magnitude of the pressure source simply by interweaving the lateral and low-resistance conducting wefts and warps over the high-resistance conducting textile, and accompanying by two scanning circuits. Therefore, the thickness and the weight of the pressure sensible textile can be substantially reduced, which improves and extends the application. Some of the examples are the pressure sensible rugs at the front door of stores, the interactive perceptive dolls, the children game carpets, the direction and speed detection carpets, and other various applications.
[0039] Although the present invention has been described in considerable detail with reference to certain embodiments thereof, other embodiments are possible. Therefore, their spirit and scope of the appended claims should no be limited to 15 the description of the embodiments contained herein.
[0040] It will be apparent to those skilled in the art that various modifications and variations can be made to the structure of the present invention without departing from the scope or spirit of the invention. In view of the foregoing, it is intended that the present invention cover modifications and variations of this invention provided they fall within the scope of the following claims and their equivalents.
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A pressure sensible textile has at least a high-resistance conducting area and two groups of low-resistance conducting wefts or warps contacting the high-resistance area directly. The two groups of low-resistance conducting wefts or warps cross each other and do not contact with each other directly. Furthermore, two scanning circuits can be electrically connected to the two groups of low-resistance conducting wefts or warps. Then, a controller is added to the two scanning circuits to obtain a pressure sensible device.
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BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a semiconductor device and manufacturing technology for that device, and relates in particular to a technology effective for applications to semiconductor devices including N-channel conductive type MISFET (Hereafter also called N channel or Nch.) and P-channel conductive type MISFET (Hereafter also called P channel or Pch.) on the same substrate and manufacturing technology for those devices.
[0003] 2. Description of Related Art
[0004] Every year the performance demanded from transistors becomes ever higher due to tough demands in recent years for more performance from equipment containing semiconductor devices. One type of tough demand on transistor performance is the transistor current drive.
[0005] One technology for enhancing the current drive performance in transistors is a technology that utilizes the stress in the silicon-nitride (SiN) interlayer film to change the stress in the channel sections and boost the transistor current drive performance.
[0006] In Nch (N channels) the stress on the channel section is along the direction of the tensile force so that better current drive performance can be expected there. Conversely, in Pch (P channels) the stress on channel section is along the direction of compression so that better current drive performance can be expected there. The channel section is also called a current path.
[0007] WO2002/043151 and JP-A-2005-057301 disclose technology for regulating the stress according to the transistor polarity.
[0008] First of all in WO2002/043151, two types of stress control films are formed in different directions on the respective P and N channels, and function to regulate the stress on the respective P and N channels.
[0009] The film thicknesses of the respective stress control films also control the amount of stress on the respective P and N channels.
SUMMARY OF THE INVENTION
[0010] However, the above example of the related art requires respectively different stress control films for the P and N channels. Namely, after forming either a compression or a tensile stress control film on both the P and N channels, the process for removing one stress control film and leaving a stress control film on only either the P channel or N channel must be repeated two times, once for the P channel and once for the N channel. In other words, the number of processes is increased.
[0011] The semiconductor device of this invention is characterized in respectively optimizing the channel stress on the P channel and N channel by utilizing stress control films possessing different stress along the direction of the film thickness.
[0012] This stress control film more preferably controls the stress state of the P and N channel sections prior to forming that stress control film to the reverse of the stress state.
[0013] This stress control film further sets the direction of stress along the film thickness according to the stress on the channels of the transistor.
[0014] In the present invention as described above, the stress on the respective P and N channel sections can be controlled with good accuracy in a simple manufacturing flow by forming a stress control film jointly on the P and N channels in only one layer and then etching away this stress control film only on either the P or the N channel side.
[0015] The stress on the channel sections can in addition be controlled within a wider range by forming the stress control film according to the channel section stress state from compression to tensile, or from tensile to compression in the direction of film thickness.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] FIG. 1 is a drawing showing the cross section of the transistor of the first embodiment of this invention;
[0017] FIG. 2 is a drawing showing a portion of the manufacturing process for the transistor of the first embodiment of this invention;
[0018] FIG. 3 is a drawing showing a portion of the manufacturing process for the transistor of the first embodiment of this invention;
[0019] FIG. 4 is a drawing showing a portion of the manufacturing process for the transistor of the first embodiment of this invention;
[0020] FIG. 5 is a drawing showing a portion of the manufacturing process for the transistor of the second embodiment of this invention;
[0021] FIG. 6 is a drawing showing a portion of the manufacturing process for the transistor of the second embodiment of this invention;
[0022] FIG. 7 is a drawing showing a portion of the manufacturing process for the transistor of the second embodiment of this invention;
[0023] FIG. 8 is a drawing showing a portion of the manufacturing process for the transistor of the second embodiment of this invention;
[0024] FIG. 9 is a drawing showing a portion of the manufacturing process for the transistor of the second embodiment of this invention;
[0025] FIG. 10 is a drawing showing a portion of the manufacturing process for the transistor of the second embodiment of this invention; and
[0026] FIG. 11 is a drawing showing a portion of the manufacturing process for the transistor of the second embodiment of this invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0027] The above and other objects, features and effects of this invention will be further clarified in the following description of the embodiments of the present invention while referring to the drawings.
First Embodiment
[0028] FIG. 1 through FIG. 4 are drawings showing the semiconductor device of the first embodiment of this invention.
[0029] FIG. 1 shows the cross section along the adjoining P and N channel directions in the present embodiment. In this embodiment, the case is described where the stress on the P and N channels sections is achieved by a compressive force. The arrows in the figure show the direction of stress from an inward compressive force and an outward tensile force.
[0030] Examining the stress control film 5 as shown in FIG. 1 clearly shows that the N channel region is a thin film thickness compared to the P channel region. The stress directions are different on the respective N and P channels.
[0031] The manufacturing flow in FIG. 1 is described next utilizing FIG. 2 through FIG. 4 in order to provide a more detailed description. A P channel is first of all formed on the right and an N channel on the left, enclosing the device isolation 1 on the semiconductor substrate 10 . An N diffusion region 4 and a P diffusion region 41 are respectively formed to serve as the drain and source. Moreover, a gate 6 is formed by way of a gate insulation film 2 on the respective N and P channels. A sidewall insulation film 6 is also formed on the side wall of that gate. In this embodiment, the channel section for both the N channel and P channel are the stress compression directions as also shown in the figure by the arrows.
[0032] As next shown in FIG. 3 , the stress control film 5 later serving as the etch-back stopper on the transistor, is jointly formed on the N and P channels. This stress control film 5 is formed (to change) from a tensile to a compression stress in the direction of the film thickness as shown by the arrows in the upper and lower two stages in the figure.
[0033] The upper and lower two stages in the figure are here described next. In the case shown by the concept diagram of this figure, the stress control film has maximum tensile stress at the bottom layer along that film thickness, and maximum compression stress at the highest layer. In other words, the stress on the stress control film gradually changes from a tensile force to a compression force along the direction of that film thickness.
[0034] In the stress control film of this embodiment, the reason that the tensile stress is at the bottom layer is due to the compression stress on the channel sections.
[0035] The film forming conditions for the above described change from a tensile to a compression stress are briefly described here. When for example forming an SiN film by the plasma CVD method, conditions are set in the initial film forming period that generate compression within the reaction chamber, and RF (high frequency) power to generate a tensile stress. Then, as the film forming progresses, the above conditions transition to conditions for generating a compression stress. Moreover, the SiN film can also be easily formed by reversing the above conditions from a compression to a tensile stress. In the present embodiment, the example described the case where SiN was the stress control film but the present invention is not limited to SiN, and any film functioning as an etching stopper and capable of controlling stress on the channel sections may be utilized.
[0036] The stress distribution in this embodiment is next briefly described while referring to the graphs in FIG. 5 through FIG. 8 . In the initial film forming stage, a tensile force is generated in the stress control film, and a compression stress finally generated as already described. The graphs in FIG. 5 and FIG. 7 show plots of stress along the stress control film thickness on the horizontal axis, and show other stress values along the vertical axis.
[0037] The stress on the stress control film consecutively changes in stages in FIG. 5 , and changes continuously in FIG. 7 .
[0038] FIG. 6 and FIG. 8 are graphs showing a plot of the total stress on the other points along the vertical axis versus the stress along the film thickness in the horizontal axis respectively in FIG. 5 and FIG. 7 . In a detailed description of FIG. 6 , the tensile stress increases from point A, and finally reaches a peak at point B. The film is then formed in the compression direction so the stress shifts toward the compression direction, and finally achieves the neutral state at point C.
[0039] FIG. 8 is the same except for the rate of change. This graph only expresses the concept type so numerical values in FIG. 6 are larger among the numerical values along the vertical axis shown in FIG. 5 and FIG. 6 .
[0040] Though not plotted in FIG. 5 through FIG. 8 , the C point is more than likely to be exceeded. In other words, the stress control film may even be formed extremely thick during manufacture. The stress control film thicknesses shown in FIG. 5 through FIG. 8 may be set from point A to point C, or to point C or higher as desired according to the stress needed on the channel sections.
[0041] FIG. 5 through FIG. 8 showed examples for changing the stress on the stress control film from tensile to compression. Conversely, if changing from compression to tensile, then the respective directions for compression and tensile in the figure will be reversed.
[0042] After forming this type of stress control film, a mask 11 is applied to cover just the P channel region, and the stress control film 5 on the N channel region is etched (etch back). A section of stress control film 5 with a tensile stress on the bottom layer in this way remains on the N channel region, the compression stress on the N channel section is canceled out, and is changed to a tensile stress as shown by the direction of the arrows in the figure. The channel for the P channel region is still under a compression stress. Both the N and P channels can in this way be set to the desired stress. In the figure, a stress control film directly contacts the diffusion regions 4 , 41 ; however, a thin oxide film may in fact be present in some cases.
[0043] The subsequent processes such as forming holes in the contact performed on the transistor formed in this way are omitted here.
Second Embodiment
[0044] The second embodiment of this invention is described next while referring to FIG. 9 through FIG. 11 . In the case described in the first embodiment, the channel regions below the gate are subject to a compression force after forming the gate insulation film and the N and P channel gate electrodes.
[0045] Here, the case is described where each channel section of the N and P channels are subject to a tensile force as shown in FIG. 9 by the outward facing arrows.
[0046] Unlike the first embodiment, a stress control film 5 later functioning as an etching stopper for the transistor is formed next while conforming to the condition that the stress transitions from a compression to a tensile force along the direction of film thickness as shown in FIG. 10 .
[0047] The reason the stress control film of this embodiment is subject to compression stress in the bottom layer is because there is a tensile stress on the channel section.
[0048] A mask 11 is then applied to cover just the N channel region, and the stress control film 5 on the P channel region is etched (etch back) as shown in FIG. 11 . A section of stress control film 5 with a compression stress on the bottom layer in this way remains on the P channel region, the tensile stress on the P channel section is canceled out, and is changed to a compression stress as shown by the direction of the arrows in the figure. The channel in the N channel region remains a tensile stress. Consequently, a tensile stress can be generated on the N channel section, and a compression stress generated on the P channel section the same as in the first embodiment.
[0049] The present invention is not limited to the above described embodiments and as is apparent to those skilled in the art the embodiments maybe modified as desired. In the first and second embodiments for example, immediately after forming the stress control film, the stress control film was etched back in order to optimize the stress on the channel sections of the transistor, however the invention is not limited to this method. In other words, when the stress on the channel regions tended towards either the compression or tensile direction in the subsequent manufacturing processes, there was no need to optimize the stress on the channel sections ahead of time according to the type of stress immediately after forming the above described stress control film. The thickness of the initial stress control film for example may be set for the C point or higher in FIG. 6 . Moreover the stress control film itself is not limited to silicon-nitride (SiN) film.
[0050] Moreover, a conventional bulk type transistor was utilized here however the invention is not limited to this type of transistor, and Silicon-On-Insulator (SOI) type transistors may also be utilized. Also, if forming a stress film to control the stress on the channel sections then needless to say, a fin-shaped FET (FinFET) may also be utilized.
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Semiconductor devices required forming a stress control film to handle different stresses on each side when optimizing the stress on the respective P channel and N channel sections. A unique feature of the semiconductor device of this invention is that P and N channel stress are respectively optimized by making use of a stress control film jointly for the P and N channels that conveys stress in different directions by utilizing the film thickness.
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BACKGROUND OF THE INVENTION
The present disclosure relates to the manufacture of a sheet of disintegrable paper and its use for manufacturing a core forming a roll support. It relates in particular to the field of paper for sanitary or household use, packaged in rolls with cores.
Papers for sanitary or household use, such as toilet paper, wiping paper or household roll towels, are sometimes packaged in rolls with cores.
The core is a cylinder, generally made from cardboard, which is discarded after the paper of the roll has been consumed. The core performs several functions:
It serves as a support on which the sheet of paper is wound in the fabrication of the roll. In general, the rolls are manufactured from a very wide stock sheet that is wound around a tube of matching length, and the roll obtained is cut into individual rolls to the desired width. It keeps the central hole open by withstanding the internal stresses of the roll and by preventing the collapse of the internal windings of the roll. It maintains the roll in shape by withstanding the crushing forces along its axis or transverse forces to which the roll is subjected during transport or during the various handling operations before its use. The core is generally obtained by helical winding and bonding of one or more bands of cardboard around a cylindrical form.
Flat cardboard is an inexpensive material which can be made from recycled fibers. It is also lightweight and its mechanical strength is sufficient for this use.
However, it has the drawback of being non-reusable or unusable in another form after the roll is consumed, and of becoming a waste product.
In the case of toilet paper, it is not recommended to discard the standard core by attempting to dispose of it with the wastewater, because, although it consists mainly of paper fibers, it disintegrates slowly in contact with water and forms a plug before it can be flushed by the stream.
BRIEF DESCRIPTION OF THE INVENTION
Accordingly, it would be advantageous to produce a core for rolls which can be disposed of easily with the wastewater of a household sanitary installation.
More particularly:
The core should preferably disintegrate in contact with water. The material should preferably disintegrate in the water at a sufficient speed for it to be removed before forming a plug; the speed at which it disintegrates should preferably be comparable to that of the tissue paper which constitutes the roll. The core should preferably have crush strength, both radially and axially, that is similar to that of the cardboard which it is intended to replace. The core should be as inexpensive to produce as the cardboard cores of the prior art. The core should be environmentally friendly.
The manufacture of the core entails the manufacture of the constituent paper sheet.
Thus, an embodiment of the invention is a method for manufacturing a sheet of paper having the property of disintegrating in water.
According to an embodiment of the invention, the method for manufacturing a sheet of paper that disintegrates in water comprises the following steps: supplying at least one band of water-soluble binder material in the form of a dry film, supplying at least two bands each formed from at least one ply of cellulose fiber, placing the band of water-soluble binder material between the two bands of cellulose fiber, wetting, joining and pressing the three bands, drying the complex band obtained.
The complex band obtained is not limited to two bands of cellulose fiber. In general, at least two bands of water-soluble binder material are joined with at least three bands of cellulose fiber, the bands of water-soluble binder material being inserted between the bands of cellulose fiber. Thus the finished sheet obtained may comprise up to, for example, 24 plies of cellulose fiber, preferably up to 10 plies.
The method of application of the film or films may vary. The same applies to the wetting of the film. For example, according to one embodiment, the method comprises at least one step in which a band of water-soluble binder material is placed on a band of cellulose fiber and the band of water-soluble binder material is wetted before placing a band of cellulose fiber on said band of water-soluble binder material.
According to one feature, the sheet comprises a quantity of water-soluble binder representing, when dry, between 20 and 70% and preferably between 25 and 50% by weight of the finished sheet.
According to one embodiment, the water-soluble binder comprises starch which is capable of conferring both dry strength and solubility in water to the sheet.
According to one feature, the basis weight of the finished sheet is between 80 and 400 g/m 2 .
According to another feature, the sheet is calendered before drying or after drying to obtain a sheet having a thickness between 0.3 and 1.2 mm, preferably between 0.4 and 0.5 mm.
The sheet thus obtained is used for manufacturing a roll support core by helical winding of one or more bands taken from said sheet around a cylinder.
The structure of the core has the advantage of allowing controlled disintegration, combined with strength comparable to that of cardboard.
An embodiment of the invention also relates to a sheet of paper that disintegrates in water, obtained by the method disclosed herein, having a basis weight of between 80 and 400 g/m 2 , containing 20 to 70% of water-soluble binder such as starch.
An embodiment further includes a core for rolls, consisting of a helical winding of one or more bands of paper consisting of a sheet of paper according to the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
Exemplary and nonlimiting embodiments of the invention are now described in greater detail, with reference to the appended drawings in which:
FIG. 1 shows a first installation in a side elevation view used for manufacturing a sheet of paper with the insertion of a water-soluble film, suitable for making a core in accordance with an embodiment of the invention,
FIG. 2 shows a first alternative embodiment with a different method of application of the water to the water-soluble film in accordance with an embodiment of the invention,
FIG. 3 shows another alternative with another method of application of the water to the water-soluble film in accordance with an embodiment of the invention,
FIG. 4 shows another alternative arrangement of the rolls for making a sheet from five bands of cellulose fiber in accordance with an embodiment of the invention,
FIG. 5 shows a cross section of the structure of an embodiment of a complex sheet obtained according to an embodiment of the invention.
DETAILED DESCRIPTION OF THE INVENTION
According to the example of manufacture shown in FIG. 1 , the installation comprises two superimposed rolls, having parallel axes and rotating about their respective axis: a smooth steel roll 3 and a roll 5 of rubber or other material. The two rolls rotate upon one another. Two bands of cellulose fiber, B 1 and B 2 respectively, are unwound from feed bobbins. The bands of cellulose fiber are formed from at least one ply, preferably one or two plies. The band B 1 is guided to the roll 3 to which it is applied. The band B 2 is guided to the roll 5 , at the interval between said roll and the roll 3 . A band of water-soluble binder material in the form of a water-soluble film F, placed between the two bands B 1 and B 2 , is guided from a feed bobbin to roll 3 where it is applied against the band B 1 . A first applicator of liquid 7 , of water, projects a measured quantity of water toward the band F, while said band bears against the band B 1 on the roll 3 . The binder deposited in the form of film reacts with the water applied. Due to the rotation of the roll 3 , the two wetted bands B 1 and F reach the interval between the two rolls, where the band B 2 joins them and is superimposed on the band F. The film is thus sandwiched between the two bands. Due to the moisture and the pressing in the interval, the band of cellulose fiber B 2 is joined to the band B 1 through the water-soluble film F that is made tacky in the wetted state.
At the outlet of the roll 5 , the complex band BF is guided from the two rolls 3 and 5 , optionally to a calendering station, not shown, and a suitable drying station. In order to obtain a thick sheet, the band BF is guided to another station where another band is applied, said band being formed of a water-soluble binder material film and another band of cellulose fiber with application of a liquid to wet the film and to allow the joining by pressing.
As many bands of cellulose fiber are joined thereby with the insertion of bands of water-soluble film as required by the desired strength and thickness of the complex sheet.
When the band F is fairly thick, it may be desirable for good adhesion of the film to the cellulose fiber, to spray water in a measured quantity on the two faces of the film. The water may be applied in liquid or vapor form.
The pressing and drying, and optionally the calendering, are adjusted to obtain the desired final thickness and strength of the product.
The sheet continuously produced thereby is processed into rolls for subsequent use.
The manufacturing parameters of the sheet BF are determined so as to obtain a core having the desired properties.
The fibers used are long, short or recycled paper fibers, and also mixtures thereof.
For each band of cellulose fiber, the basis weight is between 15 and 50 g/m 2 , preferably between 30 and 40 g/m 2 .
According to an embodiment, the water-soluble binder is starch.
The starch comprises natural products of plant origin such as wheat, corn, potato, rice starch, tapioca, sorghum and others, consisting of high molecular weight polymers or polyholosides. In the context of an embodiment of the invention, starch also includes products derived from natural starch, converted by physical treatment, for example heating, physicochemical treatment or biological treatment, for example enzymatic, of the derivative or modified starches such as cationic, anionic, amphoteric, nonionic or cross-linked starches and products resulting from the hydrolysis of starch such as maltodextrins.
The starch is selected so that its rate of dissolution is suitable with the quantity of water added.
Other binders are feasible insofar as they perform the same function. The binder may, for example, be a polyvinyl alcohol. Other additives may also be incorporated, to provide an additional function, such as disinfectants, cleansing agents or perfumes.
The binder is preferably dyed to allow inspection of the proper distribution of the binder on the 2 faces. This also has an aesthetic advantage.
The quantity of binder in the sheet is between about 20% and about 70% of the total weight of the sheet.
The sheet calendered downstream of the press has a thickness of between 0.3 and 1.2 mm.
The incorporation of water-soluble binder in the form of a dry film has the advantage of making handling easier.
FIG. 2 shows an alternative embodiment of the invention. The two rolls 3 and 5 may be observed, and the same feed of the two rolls. Water is applied here by means of an applicator 10 . It comprises an engraved roll 12 immersed in a water reserve 13 with transfer to a smooth applicator roll 11 that deposits a measured quantity of water on the band F. The applicator roll 11 bears on the roll 3 via the assembly of B 1 and F. If necessary, an additional quantity of water is applied by a spray 8 on the opposite side of the film F before it is pressed against the roll 3 .
FIG. 3 shows another alternative, in which the band formed from the water-soluble film is introduced directly into the interval between the two rolls 3 and 5 , and against which the bands of cellulose fiber are pressed. Furthermore, the band F, before its joining with the two bands of cellulose fiber B 1 and B 2 , is wetted by two water sprays 7 and 7 ′, placed on either side of the band.
FIG. 4 shows an installation for directly manufacturing a water-soluble paper from three bands of paper B 1 , B 2 and B 3 . Each of the bands is unwound from a stock bobbin, and is formed from at least one ply of cellulose fiber.
Compared to the preceding installations, a second roll 3 ′ has been added, rotating on the roll 3 . The bands of cellulose fiber B 1 and B 3 are guided respectively to the rolls 3 and 3 ′. A band of water-soluble film F 1 and F 2 respectively is applied to each of these two bands. At the same time, a measured quantity of water is applied to the free surface of the films by the two applicators 10 and 10 ′. As in the installation of FIG. 2 , the applicators 10 and 10 ′ have cylinders 12 , 12 ′ immersed in a water reserve 13 , 13 ′. The water thus tapped off is deposited by the coating rolls 11 and 11 ′ on the free surface of the films F 1 and F 2 . The third band of cellulose fiber B 2 is guided into the interval arranged between the two rolls 3 and 3 ′. Two auxiliary applicators are optionally positioned in order to wet the opposite face of the water-soluble films F 1 and F 2 .
The bands are joined between the two rolls 3 and 3 ′, and the assembly then passes between the roll 3 and the rubber roll 5 to undergo pressing.
Manufacture of the Core
The sheet of paper thus formed is cut into bands of low width which are helically wound around a cylindrical form. An adhesive is applied to the parts of the windings that are superimposed to bind them together and form a tube.
The technique for manufacturing cores is known per se. It is adapted to the type of binder, insofar as it is necessary to consider the rapid disintegration of the bands by the adhesive used to join the strands.
FIG. 5 shows a cross section of an example embodiment of a disintegrable complex sheet C according to an embodiment of the inventive method.
This structure consists of the stack of 5 plies Cn: C 1 to C 5 of cellulose fiber joined together by 4 adhesive layers C′n: C′ 1 to C′ 4 , each prepared from a water-soluble film based on polyvinyl alcohol. The film used was type BT (low temperature) sold by Plasticos Hidrosolubles.
Each of the layers of cellulose fiber Cn had a basis weight of 34 g/m 2 .
The weight of each of the layers C′n was 26 g/m 2 .
It is determined that the complex sheet obtained incorporates 0.61 g of water-soluble binder per gram of cellulose fiber.
After being cut into bands, such a sheet is suitable for manufacturing a core for a paper roll.
Compression and Disintegration Tests
A cylindrical roll was then prepared from two previously formed sheets.
Diameter and length of the cylinder forming the core: 40 mm/97 mm.
Compression Test:
The flat and edge compressive strengths of the core were measured using the following method.
The core to be tested is first cut in a cylindrical portion bounded by two opposite faces, perpendicular to the axis of the cylinder, said portion having a length of 50 mm in a direction parallel to the axis.
This cylindrical portion is then positioned between the two metal plates of a dynamometer, said plates being parallel to one another and initially separated by a distance slightly greater than the length of the cylindrical portion, in the case of the edge compression measurement, or to its diameter, in the case of the flat compression measurement.
In measuring the edge compressive strength, the cylindrical portion is positioned so that the cylinder axis is perpendicular to the plane formed by one or the other of the plates.
In measuring the flat compressive strength, the cylindrical portion is positioned so that the cylinder axis is parallel to the plane formed by one or the other of the plates.
Said cylindrical portion is then pressed between the two plates, with measurements for a compression distance at which the force is recorded in Newtons.
The resistance offered by the core is simultaneously measured up to its maximum, that is to say, just before the core is irreversibly destructured.
The results were compared with those of a reference cardboard core of the one-strand type with a wall having a basis weight of 365 g/m 2 .
It was therefore found that a core of the invention containing 0.6 g of binder per g of fibers had an edge strength at least similar to, or even greater than, that of a cardboard core, with improved compressive strength.
Since the main stresses applied to the core during its production and roll distribution cycle are essentially applied flat, the core of the invention can be considered to fully meet the requirements in this respect.
Disintegration Test:
The disintegration capacity of the core as manufactured above was measured, according to standard NF Q34-020.
It was found to disintegrate very easily.
It was also observed that the core began to disintegrate in the water faster than a similar cardboard core obtained by winding a single band of cardboard having a basis weight of 280 g/m 2 .
The core of the invention therefore disintegrates faster than a similar cardboard core formed from a single band having a basis weight of 280 g/m 2 , whether with or without stirring.
In the context of the present invention, similar core means a core having substantially the same diameter and the same length as the core of the invention.
Furthermore, for further comparison, the Afnor NF Q34-020 test was used to measure that the windings of a cardboard core having a basis weight of 400 g/m 2 (2 strands) separated after 30/60 seconds, and the core began to disintegrate after 3 minutes. It was completely disintegrated after 10 minutes but pieces of cardboard remained.
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A method for making a water-degradable paper sheet involves the following: providing at least one strip of a water-soluble binding material in the form of a dry film; providing at least two strips each made of at least one ply of cellulose wadding; placing the strip of water-soluble binding material between the two strips of cellulose wadding; humidifying, assembling and pressing the three strips; and drying the complex strip thus obtained. The sheet thus obtained can be used for making a roll carrier mandrel by helically winding one or more strips from the sheet about a cylinder. Articles produced from the sheet can particularly be used in the field of products for sanitary or domestic use.
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BACKGROUND INFORMATION
[0001] (1) Field of the Invention
[0002] This invention is generally related to image coding and more particularly to the use of the discrete wavelet transform (DWT) during compression and decompression of images.
[0003] (2) Description of the Related Art
[0004] Image compression is commonly used to reduce the storage requirements and increase the transmission speed of images by representing the images using a smaller set of data. Starting with original pixel data that captures a scene, high performance image compression algorithms often use the mathematical technique of the discrete wavelet transform (DWT) in combination with a quantization methodology to obtain a smaller set of compressed data representing the image. The inverse of these operations are performed sequentially, beginning with the compressed data, to obtain decompressed image data which should accurately represent the image. One of the problems, however, of using this DWT-based approach is the occurrence of ringing artifacts when displaying the image using the decompressed data. The ringing artifacts are similar to the double outlines often seen on a television having poor reception. The artifacts are particularly noticeable by the human eye in images of scenes having low brightness content around objects with sharp edges or low contrast regions. The artifacts become more pronounced when using stronger quantization to obtain a smaller set of compressed data. Although strong quantization yields more compact data, the displayed image following decompression of such data suffers. Therefore, a novel technique for reducing ringing artifacts after decompression of a DWT-based compressed image is desirable.
SUMMARY
[0005] According to an embodiment of the invention, a method is disclosed wherein second data is generated in response to performing at least one discrete wavelet transform based upon first data representing an image, noise is combined with the second data to generate third data, and the third data is quantized into fourth data representing the image.
[0006] Other features and advantages of various embodiments of the invention will be more apparent by referring to the description and claims below.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] [0007]FIG. 1 illustrates a flow diagram of compression and decompression according to an embodiment of the invention.
[0008] [0008]FIG. 2 shows a flow diagram of image coding according to another embodiment of the invention.
[0009] [0009]FIG. 3 depicts multiple DWTs being performed starting with original image data.
[0010] [0010]FIG. 4 shows an imaging system application as an embodiment of the invention.
DETAILED DESCRIPTION
[0011] As briefly summarized above, the method according to an embodiment of the invention involves adding noise to transform data after performing a DWT and before inverse-transforming to obtain the decompressed image data. Experimental results of performing a compression and decompression according to such a sequence show that ringing artifacts that appear when displaying the decompressed image data are reduced as compared to using the same sequence but without adding noise to the transform data. Also, in certain embodiments of the invention, particularly those in which multiple DWTs are performed, the addition of noise to a relatively small portion of the transform data may permit speedy compression. Such versions may be particularly suitable for implementation in imaging devices having limited resources, such as the digital camera or low cost video cameras.
[0012] [0012]FIG. 1 illustrates an embodiment of the invention as a method of compression and decompression of original image data. The methodology of FIG. 1 begins with applying a DWT 102 to original image data 101 to obtain original transform data 106 . The image data 101 may be a 512×512 array of pixels as shown in FIG. 3. The original image data 101 may be obtained using any conventional means, including the use of a digital camera having a solid-state image sensor. Some preprocessing 105 may optionally be performed upon raw image sensor data to obtain the original data 101 . The pre-processing may feature the removal of fixed pattern sensor noise, color correction, tone adjustment, or other known processing steps.
[0013] Applying a single DWT 102 yields original transform data 106 a that comprises wavelet coefficients in four groups called subbands LL, LH, HL, and HH (see FIG. 3). After performing the DWT 102 , noise N ab (m,n) is added to one or more selected ab subbands where in this example a single subband is selected, i.e., ab=LL. The noise adjusted subbands together with the remaining unadjusted ab subbands are then fed to a quantization block 110 which yields compressed data 114 . The compressed data 114 represents the image but requires less storage space than the original image data 101 , primarily due to the quantization 110 . The quantization 110 is generally designed to reduce the so-called bit depth of each received data value. For instance, data values that are approximately zero are replaced by zero, thus allowing these values to be stored using less space.
[0014] Returning to FIG. 1, to achieve further compression, entropy encoding 111 is normally performed following the quantization 110 to yield encoded data 117 . Entropy Encoding, e.g., Huffman encoding or run-length encoding, is designed to yield, on average, a shorter representation of the original image by using physically shorter code words for the more frequently occurring data values, and longer code words for the less likely occurring data values. The compressed data 114 or the encoded data 117 may then be transmitted or stored as needed by the imaging system application.
[0015] In order to recover the original image, the compressed data 114 is decompressed beginning with inverse quantization 120 to obtain decoded transform data 116 . Of course, if entropy encoding 111 had been performed during the compression stage, then the encoded data 117 is subjected to entropy decoding 115 prior to being subjected to the inverse quantization 120 . The inverse quantization 120 is normally the inverse of quantization 110 as known to those of ordinary skill in the art. Next, low pass filtering 124 may be applied to the adjusted subbands ab of the inverse quantized transform data 116 . The addition of noise to the original transform data 106 may create the possibility of undesirable edge information in the adjusted transform data. Therefore, the low pass filtering 124 is designed to smooth such undesirable edges, towards ultimately making the decompressed image appear more pleasant to the human eye. The low pass filtering may be achieved by averaging the inverse quantized transform data 116 in local regions. The appropriate filtering for any given application can be readily developed by one of ordinary skill in the art in view of the amount of noise N ab (m,n) that was added and the content of the original image.
[0016] After the adjusted subband has been subjected to the low pass filtering 124 , the filtered transform data 119 , having the same subband structure LL, LH, Hl, and HH as the original transform data 106 , is subjected to an inverse DWT 128 to obtain decompressed data 130 representing the original image. The inverse DWT 128 corresponds to the inverse of the DWT 102 that was performed during compression. The details of the inverse DWT 128 are either well known or can be readily developed by one of ordinary skill in the art. It should be noted that the inverse DWT 128 does not by definition decompress. The use of “decompressed” to describe the data 130 is to clarify at a more practical level the result of the above-described sequence of mathematical steps.
[0017] The noise N ab (m,n), where the m,n indices refer to the spatial location in the original transform data 106 and ab is the subband to be adjusted. As an example, the noise may have a gaussian probability density. If using the gaussian density, noise having a low variance (a) is preferred. If the variance is too large, then too much noise is introduced into the coding scheme, resulting in the decompressed image having an unacceptable quality. On the other hand, the variance should not be so low as to have little effect on the ringing artifacts that might otherwise appear if no noise were added to the coding scheme. Another possible noise function is one having a uniform density.
[0018] In general, the range of noise values should be adjusted so that the decompressed images have acceptable quality. If the magnitudes of the wavelet coefficients in the selected subbands of the original transform data 106 are relatively large, then the noise values may be proportionally larger, without degrading the quality of the decompressed image. Also, the variance of the noise may scale with the magnitudes of the wavelet coefficients in the selected subband.
[0019] The noise N ab (m,n) may be combined with the original transform data 106 in one of several ways. For instance, a noise value randomly selected from a group of values may be added to each wavelet coefficient at location m,n in the ab subband. The group of values may be pre-determined by the particular probability density function selected. The same group of values may be used for a number of images. Alternatively, the noise values may be adapted to each original image based on the content of the image. Other ways of determining and adding the noise values to the transform data may be readily developed by those of ordinary skill in the art.
[0020] Another issue to consider when selecting the particular technique for combining noise with transform data is the computation required for determining the noise values and/or the space required for their storage. The additional computation and/or storage required for computing the nose values and adding the values to the original transform data 106 is to be balanced against the improvement obtained in the decompressed image. This issue may be particularly important when the compression stage of FIG. 1 occurs in an imaging device having limited resources, such as a portable digital camera.
[0021] [0021]FIG. 2 illustrates another embodiment of the invention as a coding scheme involving the addition of noise to transform data. In this embodiment, the compression and decompression sequences may be the same as in the embodiment of FIG. 1 except that the noise N ab (m,n) is added after the inverse quantization 120 rather than before. The noise N ab (m,n) is thus added during the decompression stage rather than during compression. Decompression may begin with inverse quantization 120 , followed by the addition of noise N ab (m,n) to the selected ab subbands, followed by low pass filtering 124 of the ab subbands, and finally the inverse DWT 128 to obtain decompressed data 132 . Just as in the embodiment of FIG. 1, additional compression using, for instance, entropy encoding 111 following quantization 110 , may be performed. Any corresponding entropy decoding is performed prior to the step of inverse quantization 120 in the decompression stage.
[0022] [0022]FIG. 3 presents several alternatives to the embodiments of the invention in FIGS. 1 and 2 described above. In FIGS. 1 and 2, the DWT 102 was applied only once to the original image data 101 to decompose the image into four subbands, one low frequency LL subband and three other frequency subbands referred to as LH, HL, and HH. This first level of decomposition is indicated by the transform data 106 a in the sequence of FIG. 3. As shown in FIG. 3, however, the DWT 102 may be applied several times in succession in order to obtain successively smaller ab subbands to which the noise N ab (m,n) may be added. Thus, the transform data 106 referred to in FIGS. 1 and 2 may be any one of the transform data 106 a, 106 b, or perhaps 106 c, depending on the number of times the DWT 102 is applied in succession.
[0023] Regardless of the number of times the DWT 102 is applied in the compression stage, only the selected subbands ab are combined with the N ab (m,n) and the low pass filtering 124 . As the successive subbands are smaller, there are fewer noise and low pass filtering operations to be performed. This may yield faster compression, provided the increase in computation and storage resources for the additional DWTs do not offset the decrease obtained due to the smaller subbands. Note that whenever more than one DWT 102 is applied in the compression stage, then a corresponding a number of inverse DWTs 128 are applied in the decompression stage so that the decompressed data properly represents the original image.
[0024] [0024]FIG. 4 shows a system application of the compression and decompression stages described above, according to another embodiment of the invention. In this embodiment, the compression may be implemented using a programmed processor with instructions aboard a semiconductor read only memory (ROM), or as dedicated logic circuitry, or as a combination of the two, aboard an imaging device such as a digital camera 404 . The transform data obtained after the quantization 110 may be stored in a removable storage device 408 such as a non-volatile memory card and then transferred to a processing system 412 . Alternatively, the compressed data may be transferred to the processing system 412 via any type of computer peripheral interface bus 410 .
[0025] The decompression stages described above in FIGS. 1 and 2 are normally implemented in the processing system 412 which in one embodiment may be a personal computer (PC). The decompression stage in that embodiment would be implemented using processor instructions that may be stored in various types of machine readable media such as a semiconductor memory, magnetic disk, or CD ROM. Other imaging devices and processing systems, either in combination or as stand alone systems, may be used to implement the compression and decompression stages described above.
[0026] To summarize, various embodiments of the invention have been described above as methods of compressing and decompressing an image involving the addition of noise to DWT transform data to help reduce the occurrence of ringing artifacts in the decompressed image. The embodiments described above are, of course, subject to other variations in structure and implementation apparent to those of ordinary skill in the art. For instance, although the mathematical steps described above are normally performed directly upon the different data sets identified, it may be that scaling, offset corrections, or other operations that do not fundamentally affect the nature of the data sets are also performed prior to the mathematical steps. Also, the embodiments described may be adapted to process digital still images and digital video in a wide range of applications, including digital photography kiosks, video conferencing over a computer network, and in general any other applications that need compressed image data. It is intended that all such modifications and variations falling within the spirit and scope of the invention be covered by the appended claims.
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A method of processing an image by generating transform data in response to performing at least one discrete wavelet transform based upon original image data, generating adjusted data by combining noise with the transform data, and generating compressed data representing the image by quantizing based upon the adjusted data.
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CROSS REFERENCE TO RELATED APPLICATIONS
This application is a continuation application based on a PCT Patent Application No. PCT/JP2012/055379, filed Mar. 2, 2012, whose priority is claimed on Japanese Patent Application No. 2011-067760, filed Mar. 25, 2011 the entire content of which are hereby incorporated by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an image processing device that performs image processing on frame image data input from an imaging device.
2. Description of the Related Art
All patents, patent applications, patent publications, scientific articles, and the like, which will hereinafter be cited or identified in the present application, will hereby be incorporated by reference in their entirety in order to describe more fully the state of the art to which the present invention pertains.
When image data is transmitted by using a wireless communication line, a communication environment may deteriorate due to electromagnetic noise and predetermined image data may not be transmitted. In order to cope with such a situation, for example, a system that switches a communication protocol according to the communication environment to keep discomfort of a user to a minimum is disclosed in Japanese Unexamined Patent Application, First Publication No. 2003-69472.
SUMMARY
The present invention provides an image processing device capable of suppressing deterioration of image quality of an element, which is highly important among elements related to image quality of an image displayed on a display device, even when a communication environment deteriorates.
An image processing device according to a first aspect of the present invention includes an input unit, a storage unit an image processing unit, a wireless communication unit, a detecting unit and a selection unit. Frame image data is input to the input unit from an imaging device that images a subject and continuously outputs the frame image data. The storage unit stores a plurality of data formats corresponding to different image qualities, the data formats defining a format of at least two elements among resolution, color representation, update period and gradation that are elements related to image quality of an image displayed on a display unit continuously performing display processing on the frame image data and displaying the image. Further, the storage unit stores importance degree information indicating an importance degree of the element. The image processing unit performs image processing on the frame image data input to the input unit according to the data format selected from the data formats stored in the storage unit. The wireless communication unit continuously and wirelessly transmits the frame image data subjected to the image processing by the image processing unit to the display unit. The detecting unit detects a wireless communication environment when the wireless communication unit wirelessly transmits the frame image data. The selection unit selects one of the data formats stored in the storage unit. Further, the selection unit selects the data format defining a format lower in quality than a format defined in a currently selected data format for the element selected based on the importance degree information stored in the storage unit when deterioration of the communication environment is detected by the detection unit.
Further, according to a second aspect of the present invention, the selection unit performs selection for the element whose importance degree is indicated to be lower than those of the other elements by the importance degree information when deterioration of the communication environment is detected by the detection unit. Further, the selection unit selects the data format defining a format lower in quality than the format defined in the currently selected data format.
Further, according to a third aspect of the present invention, the storage unit stores the data format for each user, each imaging device, or each combination of the user and the imaging device.
Further, according to a fourth aspect of the present invention, the storage unit stores a plurality of first data formats, and a second data format corresponding to image quality of a highest quality for each imaging device. The selection unit performs selection based on the importance degree information stored in the storage unit when deterioration of the communication environment is detected by the detection unit. Further, the selection unit defines a format less than or equal to, in terms of quality, a format defined in the second data format corresponding to the imaging device outputting the frame image data input to the input unit for the element selected based on the importance degree information. Further, the selection unit selects the first data format, the first data format defining a format lower in quality than the format defined in the currently selected data format.
Further, according to a fifth aspect of the present invention, the storage unit stores a plurality of first data formats, and a second data format defining a format corresponding to image quality of a lowest available quality of each of the at least two elements. The selection unit performs selection based on the importance degree information stored in the storage unit when deterioration of the communication environment is detected by the detection unit. Further, the selection unit selects the first data format defining a format higher in quality than or equal in quality to a format defined in the second data format for the element selected based on the importance degree information, the first data format defining a format lower in quality than the format defined in the currently selected data format.
Further, according to a sixth aspect of the present invention, the storage unit stores the second data format for each user, each imaging device, or each combination of the user and the imaging device.
BRIEF DESCRIPTION OF THE DRAWINGS
The above features and advantages of the present invention will be more apparent from the following description of certain preferred embodiments taken in conjunction with the accompanying drawings, in which:
FIG. 1 is a block diagram illustrating a configuration of an imaging display system in accordance with a preferred embodiment of the present invention;
FIG 2 is a block diagram illustrating a configuration of a transmission device included in the imaging display system in accordance with a preferred embodiment of the present invention;
FIG. 3 is a reference diagram illustrating a format selection table in accordance with a preferred embodiment of the present invention;
FIG. 4 is a reference diagram illustrating a format table in accordance with a preferred embodiment of the present invention;
FIG. 5 is a reference diagram illustrating format selection control information in accordance with a preferred embodiment of the present invention;
FIG. 6 is a flowchart illustrating a procedure of a format selection operation in accordance with a preferred embodiment of the present invention; and
FIG. 7 is a reference diagram illustrating a format selection order table in accordance with a preferred embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention will be now described herein with reference to illustrative preferred embodiments. Those skilled in the art will recognize that many alternative preferred embodiments can be accomplished using the teaching of the present invention and that the present invention is not limited to the preferred embodiments illustrated for explanatory purpose.
Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. Hereinafter, a case in which a preferred embodiment of the present invention is applied to an imaging display system including an endoscope, a transmission device, a reception device, and a display monitor will be described by way of example. FIG. 1 shows a configuration of an imaging display system in accordance with a preferred embodiment of the present invention. In FIG. 1 , an endoscope 1 , a manipulation monitor 2 that displays an endoscope image generated by the endoscope 1 or various control screens, and a transmission device 3 that performs wireless transmission of image data are mounted on a cart 4 . A reception device 5 that receives the image data transmitted from the transmission device 3 and outputs the image data as a video signal, and a display monitor 6 that displays the video signal output from the reception device 5 as an image are mounted on a cart 7 .
The endoscope 1 continuously generates image data (frame image data) of each frame of moving image data including a plurality of frames. The image data generated by the endoscope 1 is wirelessly transmitted from the transmission device 3 to the reception device 5 , and an image is displayed on the display monitor 6 connected to the reception device 5 . The transmission device 3 converts a format of the image data output from the endoscope 1 to a data amount format according to a communication situation, packetizes data after the conversion, and wirelessly transmits a packet. Further, the reception device 5 extracts the image data from the received packet. Further, the reception device 5 performs format conversion and image processing on the extracted image data to generate the video signal, and outputs the video signal to the display monitor 6 . The display monitor 6 performs display processing on the video signal and displays the image.
FIG. 2 illustrates a configuration of the transmission device 3 . The transmission device 3 includes an image processing circuit 10 , a format conversion circuit 11 , a packet generation circuit 12 , an RF circuit 13 , a storage circuit 14 , a format determination circuit 15 , a communication environment detection circuit 16 , an entire control circuit 17 , an external device interface circuit 18 , a user interface circuit 19 , an antenna 20 , and an endoscope interface circuit 21 .
An imaging signal 8 constituting the image data and an endoscope control signal 9 are input from the endoscope 1 to the transmission device 3 . The imaging signal 8 from the endoscope 1 is input to the endoscope interface circuit 21 and is output to the image processing circuit 10 . The image processing circuit 10 performs image processing corresponding to a predetermined format on the imaging signal and outputs an imaging signal after the image processing to the format conversion circuit 11 . The format conversion circuit 11 converts a format of the imaging signal output from the image processing circuit 10 to a predetermined format and outputs the imaging signal after the conversion to the packet generation circuit 12 . The packet generation circuit 12 packetizes the imaging signal output from the format conversion circuit 11 and outputs a packet to the RF circuit 13 . The RF circuit 13 converts the packet output from the packet generation circuit 12 to a radio packet, and transmits the packet via an antenna 20 .
The image processing performed by the image processing circuit 10 is, for example, processing for performing a filtering process on data of 1920(H)×1440(V) to generate data of 800(H)×600(V) in which distortion of the image has been removed when a format at the time of wireless transmission corresponding to a case in which resolution of the imaging signal 8 is 1920(H)×1440(V) is 800(H)×600(V). Such processing is well known as preprocessing associated with format conversion. Therefore, further description is omitted.
In the present preferred embodiment, when a wireless communication environment (hereinafter described as a communication environment) deteriorates and a data amount that can be transmitted is reduced, communication is performed using a format in which transmission is possible even with a data amount after the reduction. An operation of format selection when a wireless environment deteriorates will be described below.
A state of a wireless environment is recognized by a communication situation in the RF circuit 13 . Specifically, the RF circuit 13 notifies the communication environment detection circuit 16 of a packet retransmission situation in wireless communication. The communication environment detection circuit 16 detects a change in the communication environment according to the packet retransmission situation and calculates a data amount that can be communicated.
For example, when the communication situation is good, a wireless communication scheme capable of transmitting 200 packets in a period of 1/60 of a second (about 16.7 ms) is assumed to be used. A current generation rate of retransmission packets in this wireless communication scheme is 5% on average. When transmission is to be performed with such a margin that the number of retransmission packet generations is allowed to be twice the current number, image data in a format in which 180 packets (200×0.9=180) are used for one screen can be transmitted every 1/60 of a second. The average retransmission packet number in this case is 10.
When the communication environment deteriorates and the retransmission of 20 packets is performed in a period of 1/60 of a second (about 16.7 ms), there is no margin in a communication path. Since the data transmission for one screen frequently stops on the way when there is no margin in the communication path, it is necessary to give the margin in the communication path. In the present preferred embodiment, the transmission is performed with such a margin that the number of retransmission packet generations is allowed to be twice the current number.
For example, in the case of the above example, it is determined that there has been no margin in the communication path at a time point at which the average retransmission packet number exceeds 10. In this case, a format is changed to reduce the number of packets necessary for transmission of one screen. For example, in the case of the above example, when the data for one screen is assumed to be transmitted by 100 packets as a result of changing the format, the deterioration of the communication environment progresses. As a result, a next format change is performed at a time point at which the average retransmission packet number is 50. On the other hand, when the communication environment is improved and the average retransmission packet number is changed to a current format the communication environment is determined to have been improved at a time point at which the average retransmission packet number is 5, which is half of 10, determination criterion. As a result, the format change is performed to return to an original format.
The communication environment detection circuit 16 measures a situation of the communication path using the method described above, and notifies the format determination circuit 15 of the change in the communication environment when the change in the communication path continues for a predetermined time or more. When the change in the communication environment is notified of from the communication environment detection circuit 16 , the format determination circuit 15 determines a format to be used using various pieces of information stored in the storage circuit 14 . Information of the format determined by the format determination circuit 15 is output to the image processing circuit 10 and the format conversion circuit 11 . Furthermore, the information of the format determined by the format determination circuit 15 is reflected on processes in the image processing circuit 10 and the format conversion circuit 11 .
The memory circuit 14 stores a format table, a format selection table, format selection control information, a format selection order table and the like, which will be described below. The external device interface circuit 18 is connected to the endoscope 1 through the endoscope control signal 9 . The external device interface circuit 18 acquires device ID information for identifying the endoscope 1 from the endoscope 1 and notifies the format determination circuit 15 of the device ID information via the entire control circuit 17 . The user interface circuit 19 receives various pieces of information input by the user. The user interface circuit 19 is stored in the storage circuit 14 via the entire control circuit 17 . The entire control circuit 17 is a circuit that controls the entire operation of the transmission device 3 .
FIG. 3 is an example of the format selection table in the present preferred embodiment. In the format selection table, formats of image quality elements that can be selected in the present preferred embodiment are classified according to an image quality rank.
In the present preferred embodiment, the image quality elements determining the image quality of the display image include resolution (A), color representation (B). update period (C), and gradation (D). For each image quality element, the format is defined for each image quality rank.
For example, in the resolution (A), a format corresponding to a case in which the image quality rank is 1 (highest image quality) is 1920(H)×1440(V), and a format corresponding to a case of a next image quality rank is 1280(H)×960(V). A ratio of a data amount between the two formats is 2.25 ([1920×1440]/[1280×960]=2.2S), Hereinafter, the formats of the resolution as shown are selectable.
The color representation (B) indicates a general YC format. For example, a format corresponding to the case in which the image quality rank is 1 (highest image quality) is YUV (4,4,4), and is a format in which a ratio of Y (luminance) and U and V (color) is 1:1:1. A format corresponding to the case of the next image quality rank is YUV(4,2,2) and is a format in which the ratio of Y (luminance) and U and V (color) is 1:0.5:0.5. A ratio of a data amount between the two formats is 1.5 ([1+1+1]/[1+0.5+0.5]=1.5). Hereinafter, the YC formats as shown are selectable.
The update period (C) indicates a format of a frame rate. For example, a format corresponding to the case in which the image quality rank is 1 (highest image quality) is 60 frames/second, and a format corresponding to the case of the next image quality rank is 30 frames/second. A ratio of a data amount between the two formats is 2 (60/30=2). The formats of the frame rate as shown are selectable.
The gradation (D) indicates a format of a bit length of a pixel For example, a format corresponding to the case in which the image quality rank is 1 (highest image quality) is 12 bits in length, and a format corresponding to the case of a next image quality rank is 10 bits in length. A ratio of a data amount between the two formats is 1.2 (12/10=1.2), The formats of the gradation as shown are selectable.
FIG. 4 is an example of the format table in the present preferred embodiment. The format table of FIG. 4 indicates a data format that is a combination of formats of the respective image quality elements shown in FIG. 3 . A format number corresponding to the image quality rank of the image quality element shown in FIG. 3 is attached, as shown in FIG. 4 . For example, format number=1111 indicates that the image quality rank of A: resolution of the corresponding image quality element is 1, the image quality rank of B: color representation is 1, the image quality rank of C: update period is 1, and the image quality rank of D: gradation is 1. In this case, the format in which the image quality rank of A: resolution is 1 is 1,920×1,440. The format in which the image quality rank of B: color representation is 1 is YUV(4,4,4). The format in which the image quality rank of C: update period is 1 is 60 Hz. The format in which the image quality rank of D: gradation is 1 is 12 bits.
The data format selected by the format determination circuit 15 is expressed using the format number of the format table of FIG 4 . In the present preferred embodiment each of four numbers constituting the format number defines a format of the four image quality elements. All the format numbers indicate the data formats as a set of formats of the lour image quality elements.
FIG. 5 is a structure example of the format selection control information in the present preferred embodiment. The format selection control information is information referenced by the format determination circuit 15 when the format determination circuit 15 determines the format. The format selection control information is information indicating a data format of highest image quality according to performance of the imaging device, a data format of lowest image quality specified by each user, and importance (importance degree) of each image quality element specified by each user. As shown, the format selection control information includes a device ID, a user ID, an imaging data format, allowed lowest image quality information, and important element information.
The number of the imaging data format, the allowed lowest image quality information and the important element information corresponds to the format number of FIG. 4 . Further information is arranged in order of the image quality element shown in the format table of FIG. 4 in the imaging data format, the allowed lowest image quality information and the important element information. The device ID is an ID of an imaging device that can be connected to the transmission device 3 . Further, a setting of device ID=0000 in FIG. 4 is a default setting and is a setting when format selection is performed in a case in which an imaging device whose device ID is unidentified is used. The user ID is an ID of each user of the imaging display system. A setting of user ID=0000 in FIG. 4 is a default setting of each device and is a setting when the format selection is performed in a case in which the user is not specified.
The imaging data format indicates a format of the highest image quality that can be output by the imaging device. For example, the imaging data format of device ID=ES02 and user ID=D001 is 1212. This imaging data format corresponds to a data format of format number 1212 in FIG 4 . Further, a setting of imaging data format=0000 in FIG. 5 is a default setting when the highest image qualify that can be output by the imaging device in use is unidentified. A setting of imaging data format=0000 is a setting in which the format of the input imaging signal is directly used as the imaging data format.
The allowed lowest image quality information indicates lowest image quality that can be set as display image quality. For example, the allowed lowest image quality information of user ID=D001 in device ID=ES02 is 4324. This allowed lowest image quality information corresponds to a data format of format number 4324 in FIG. 4 .
The important element information indicates order and a ratio of an element to which importance is attached at the time of format selection. The order cited herein indicates order of the image quality element whose image quality rank is changed at the time of format selection. For example, the order in the important element information of device ID=ES02 and user ID=D001 is 1234. This indicates the order of each image quality element according to the importance degree. For example, 1234 that is the order in this example indicates that importance is attached to the image quality elements in order of the resolution (order 1), the color representation (order 2), the update period (order 3), and the gradation (order 4).
Further, the ratio cited herein indicates by how many ranks a next image quality element is to be changed at a time point at which each image quality element has been changed. For example, a ratio in the important element information of device ID=ES02 and user ID=D001 is 1122. This indicates that the image quality rank of another image quality element is changed at a time point at which any one image quality element is changed by 1 rank. In the example in which device ID=ES02 and user ID=D001, since order=1234 and ratio=1122 in the important element information, the gradation is changed by 2 rank and then the update period is changed by 2 rank. It shows that the color representation is then changed by 1 rank and then the resolution is changed by 1 rank. Thus, the image quality rank of each image quality element is changed in ascending order of the importance degree.
A setting of the user ID other than 0000 is a setting specified for each user. The user can specify the lowest image quality allowed at the time of deterioration of the communication environment or the order of the image quality element to which importance is attached. When the user performs the setting of the allowed lowest image quality information or the important element information, content specified by the user is input to the entire control circuit 17 via the user interface circuit 19 . Further, the content specified by the user is stored in the storage circuit 14 by the entire control circuit 17 . Further, the entire control circuit 17 is notified of the device ID and the imaging data format from the endoscope 1 via the endoscope control signal 9 . Furthermore, the device ID and the imaging data format are stored in the storage circuit 14 by the entire control circuit 17 .
In FIG. 5 , in the setting of device ID=ES02 and user ID=D001, imaging data format=1212, allowed lowest image quality information=4324, and important element information=(1234),(1122). In this setting, the format of the highest image quality that can be output by the imaging device is resolution=1,920×1,440, color representation=YUV(4,2,2), frame rate=60 Hz and gradation=10 bits, which are indicated by format number 1212.
Further, in this setting, the allowed, lowest display image quality is resolution=800×600, color representation=YUV(4,1,1), frame rate=30 Hz, and gradation=6 bits, which are indicated by format number 4324. Further, this setting attaches importance to the image quality elements in order of the resolution, the color representation, the update period, and the gradation when the formal selection is performed. When the communication environment deteriorates, the image quality rank of the gradation drops by 2 steps and then the image quality rank of the update period drops by 2 steps according to a degree of deterioration. Then, the image quality rank of the color representation drops by 1 step. Then, the image quality rank of the resolution drops 1 step. Then, it is shown that the image quality element is selected and the image quality rank drops in the same procedure.
In the present preferred embodiment, the format selection control information for each combination of the user and the imaging device is used. On the other hand, format selection control information for each user that does not depend on the imaging device or format selection control information for each imaging device that does not depend on the user may be used.
Next, a format selection operation in the present preferred embodiment will be described. The order of the data format selected when the deterioration of the communication environment has progressed and when the communication environment has been recovered is determined by the imaging data format, the allowed lowest image quality information, and the important element information in advance, as described with reference to FIG. 5 . Therefore, in the format selection operation, a determination is made as to whether the deterioration of the communication environment has progressed or whether the communication environment has been recovered. In the format selection operation, a data format determined in advance is selected based on a currently selected data format.
FIG. 6 illustrates a format selection operation in the format determination circuit 15 . When a format selection process starts (S 1 ), the format determination circuit 15 performs an initial setting (S 2 ). The initial setting (S 2 ) is an operation of producing the format selection order table.
The format selection order table indicates order of the data format selected by the format determination circuit 15 when a communication environment is changed. FIG. 7 illustrates the format selection order table when device ID=ES02 and user ID=D001. Since imaging data format=1212, allowed lowest image quality information=4324, and important element information=(1234),(1122) when device ID=ES02 and user ID=D001 as shown in FIG. 5 , the selection order of the format is the order shown in FIG. 7 .
Specifically, when there is no deterioration of the communication environment, a data format of format number=1212 that is the imaging data format is selected. Therefore, the format number of selection order=1 in FIG. 7 is 1212. When the deterioration of the communication environment progresses, the data format is selected according to the important element information. As deterioration of the communication environment progresses, the data format is selected in order of format number=1213, format number=1214, and format number=1224, as shown in FIG. 7 .
If the deterioration of the communication environment, further progresses when the data format of format number=1224 is selected, a numerical value of the ratio of the important element information is set to 2 in a state in which the update period (two lower digits of format number=1224) is 2 (30 Hz). Therefore, the data format of format number=1234 is selected as the next data format. However, since the allowed lowest image quality information is 4324, the two lower digits of the format number are not “3” and are maintained as “2.” Instead, the color representation that is the image quality element to be changed next drops by 1 step and the data format of format number=1324 is selected as the next data format. Hereinafter, the data format is selected in order of format number=2324, format number=3324, and format number=4324 (allowed lowest image quality), as shown in FIG. 7 .
In the initial setting (S 2 ), the format determination circuit 15 produces the format selection order table shown in FIG. 7 according to the format selection control information shown in FIG. 5 and the format table shown in FIG. 4 . Further, the format determination circuit 15 is stored in the storage circuit 14 . When the initial setting (S 2 ) ends, the communication environment change wait (S 3 ) is performed. The communication environment change wait (S 3 ) is a process of waiting for a change in the communication environment to be notified of by the communication environment detection circuit 16 .
When receiving a notification indicating that the communication environment has been changed from the communication environment detection circuit 16 , the format determination circuit 15 determines whether the communication environment has deteriorated or has improved (S 4 ). When the communication environment has deteriorated, the format determination circuit 15 performs the format selection process at the time of environment deterioration (S 5 ). When the communication environment has improved, the format determination circuit 15 performs the format selection process at the time of environment improvement (S 6 ).
The format selection process at the time of environment deterioration (S 5 ) is a process of selecting a data format in which a communication data amount decreases. For example, when the communication environment deteriorates in a state of device=ES02 and user=D001, the data format in a direction in which the selection order shown in FIG. 7 is added is selected. Information of the data format selected by the format determination circuit 15 is stored in the storage circuit 14 and is used as a reference data format when the communication environment is changed next.
Hereinafter, a concrete example of the selection of the data format will be described. When the data format of format number=1212 of selection order 1 shown in FIG. 7 has been selected, a data format first selected at the time of the environment deterioration is a data format of format number=1213 of selection order 2. The format of each image quality element in the data format of format number=1213 is resolution=1,920×1,440, color representation=YUV(4,2,2), frame rate=60 Hz and gradation=8 bits.
When the communication environment further deteriorates, a data format of format number=1214 of selection order 3 is selected. The format of each image quality element in the data format of format number=1214 is resolution=1,920×1,440, color representation=YUV(4,2,2), frame rate=60 Hz, and gradation=6 bits. When the communication environment further deteriorates, a data format of format number=1224 of selection order 4 is selected. The format of each image quality element in the data format of format number=1224 is resolution=1,920×1,440, color representation=YUV(4,2,2), frame rate=30 Hz, and gradation=6 bits.
When the data format has been changed from the data format of format number=1212 to the data format of format=1224, the gradation is changed from 10 bits to 6 bits. As a result, the data amount is 30% of an original data amount since the frame rate is changed from 60 Hz to 30 Hz.
Even in this case, for the resolution and the color representation that are the image qualify elements to which the importance is attached by the user, an image is displayed with original image quality maintained.
When the deterioration of the communication environment has progressed and the data format of format number=4324 of selection order 8 corresponding to the allowed lowest image quality has been selected, the communication in the data format continues even when the communication environment further deteriorates.
The formal selection process at the time of environment improvement (S 6 ) is a process of selecting the data format in which a communication data amount increases. For example, when the communication environment has improved in a state of device=ES02 and user=D001, the data format in a direction in which the selection order shown in FIG. 7 is subtracted is selected. Information of the data format selected by the format determination circuit 15 is stored in the storage circuit 14 and is used as a reference data format when the communication environment has been changed next.
For example, when a current data format is a data format of format number=1224 in device=ES02 and user=D001, the selection order is 4. Therefore, in the format selection process at the time of environment improvement (S 6 ), a data format of format number=1214 of selection order 3 is selected.
When the format selection process at the time of environment deterioration (S 5 ) or the format selection process at the time of environment deterioration (S 6 ) ends, the process returns to the communication environment change wait (S 3 ). The format determination circuit 15 waits for a notification of a next change in the communication environment. As described above, since the important element information can be set for each user, an image can be sent with the image quality of the image quality element to which importance is attached by the user maintained to the end.
As described above, according to the present preferred embodiment, when deterioration of the communication environment is detected, the data format having a lower quality than a currently selected data format is selected according to the image quality element to which importance is attached by the user. Accordingly, even when the communication environment has deteriorated, it is possible to suppress deterioration of the image quality element having a high importance degree among the image quality elements of the image displayed on the display device.
Further, an image quality element desired to be held at the time of deterioration of the communication environment can be selected according to a characteristic of the imaging device and preference of the user by using the data format for each imaging device or each combination of the riser and the imaging device. Further, it is possible to set the lowest display image quality even when the communication environment greatly deteriorates, by selecting the data format not less than the image quality indicated by the allowed lowest image quality information. As a result, it is possible to perform a setting so that an image in an unavailable level is not displayed.
According the image processing device in accordance with a preferred embodiment of the present invention, when deterioration of the communication environment is detected, a data format defining a format lower in quality than the format defined in a currently selected data format is selected for an element selected based on the importance degree information. Accordingly, even when the communication environment has deteriorated, it is possible to suppress deterioration of image quality of an element having a high importance degree among elements related to image quality of the image displayed on the display device.
While preferred embodiments of the present invention have been described and illustrated above, it should be understood that these are examples of the present invention and are not to be considered as limiting. Additions, omissions, substitutions, and other modifications can be made without departing from the scope of the present invention. Accordingly, the present invention is not to be considered as being limited by the foregoing description, and is only limited by the scope of the claims.
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Provided is an image processing device which includes a storage unit and a selection unit. The storage unit stores a plurality of data formats corresponding to different image qualities, as data formats specifying at least two elements from among resolution, color expression, update cycle, and gradation which are elements relating to the image quality of an image displayed by a display device which continuously subjects frame image data to display processing and displays images. Furthermore, the storage unit stores importance information indicating the importance of an element. If a detection unit detects that the communication environment has degraded, the selection unit selects, for an element selected based on the importance information stored in the storage unit, a data format having a lower quality specified format than the format specified by the data format currently selected.
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CLAIM OF PRIORITY UNDER 35 U.S.C. §120
The present Application for Patent is a Continuation and claims priority to patent application Ser. No. 09/738,586, entitled “METHOD AND AN APPARATUS FOR A WAVEFORM QUALITY MEASUREMENT” filed Dec. 14, 2000, now U.S. Pat. No. 6,693,920 now allowed, and assigned to the assignee hereof and hereby expressly incorporated by reference herein.
BACKGROUND
1. Field
The current invention relates to quality assurance. More particularly, the present invention relates to a method and apparatus for waveform quality measurement.
2. Background
Recently, communication systems have been developed to allow transmission of signals from an origination station to a physically distinct destination station. In transmitting signals from the origination station over a communication link, the signal is first converted into a form suitable for efficient transmission over the communication link. As used herein, the communication link comprises a medium over which a signal is transmitted. Conversion, or modulation, of the signal involves varying a parameter of a carrier wave in accordance with the signal in such a way that the spectrum of the resulting modulated carrier is confined within the communication link bandwidth. At the destination station the original signal is replicated from a version of the modulated carrier received over the communication link. Such a replication is generally achieved by using an inverse of the modulation process employed by the origination station.
Modulation also facilitates multiple-access, i.e., simultaneous transmission and/or reception, of several signals over a common communication link. Multiple-access communication systems often include a plurality of remote subscriber units requiring intermittent service of relatively short duration rather than continuous access to the common communication link. Several multiple-access techniques are known in the art, such as time division multiple-access (TDMA), frequency division multiple-access (FDMA), and amplitude modulation (AM). Another type of a multiple-access technique is a code division multiple-access (CDMA) spread spectrum system that conforms to the “TIA/EIA/IS-95 Mobile Station-Base Station Compatibility Standard for Dual-Mode Wide-Band Spread Spectrum Cellular System,” hereinafter referred to as the IS-95 standard. The use of CDMA techniques in a multiple-access communication system is disclosed in U.S. Pat. No. 4,901,307, entitled “SPREAD SPECTRUM MULTIPLE-ACCESS COMMUNICATION SYSTEM USING SATELLITE OR TERRESTRIAL REPEATERS,” and U.S. Pat. No. 5,103,459, entitled “SYSTEM AND METHOD FOR GENERATING SIGNAL WAVEFORMS IN A CDMA CELLULAR TELEPHONE SYSTEM,” both assigned to the assignee of the present invention and incorporated herein by reference.
FIG. 1 illustrates an ideal waveform 100 of an embodiment of a code division communication system in accordance with the IS-95 standard. For the purposes of this document, a waveform is a manifestation, representation or visualization of a wave, pulse or transition. The idealized waveform 100 comprises parallel channels 102 distinguished from one another by a cover code. The cover code in a communication system according to the IS-95 standard comprises Walsh codes. The ideal waveform 100 is then quadrature spreaded, baseband filtered and upconverted on a carrier frequency. The resulting modulated waveform 100 , is expressed as:
s ( t ) = ∑ i R i ( t ) ⅇ - j ω c t ( 1 )
where:
ω c is the nominal carrier frequency of the waveform;
i is the index of the code channels summation; and
R i (t) is the complex envelope of the ideal i-th code channel.
Equipment, e.g., a transmitter of the code division communication system, generates actual waveform x(t) that is different from the ideal waveform. Such an actual waveform x(t) is expressed as:
x ( t ) = ∑ i b i [ R i ( t + τ i ) + E i ( t ) ] · ⅇ - j [ ( ω c + Δ ω ) ( t + τ i ) + θ i ] ( 2 )
where:
b i is the amplitude of the ideal waveform relative to the ideal waveform for the i th code channel;
τ i is the time offset of the ideal waveform relative to the ideal waveform for the i th code channel;
Δωis the radian frequency offset of the signal;
θ i is the phase offset of the ideal waveform relative to the ideal waveform for the i th code channel; and
E i (t) is the complex envelope of the error (deviation from ideal) of the actual transmit signal for the i-th code channel.
The difference between the ideal waveform s(t) and the actual waveform x(t) is measured in terms of frequency tolerance, pilot time tolerance, and waveform compatibility. One method to perform such a measurement is to determine modulation accuracy defined as a fraction of power of the actual waveform x(t) that correlates with the ideal waveform s(t), when the transmitter is modulated by the code channels. The modulation accuracy is expressed as:
ρ overall = ∫ T 1 T 2 s ( t ) · x ( t ) * · ⅆ t { ∫ T 1 T 2 s ( t ) 2 · ⅆ t } · { ∫ T T 2 x ( t ) 2 · ⅆ t } ( 3 )
where:
T 1 is beginning of the integration period; and
T 2 is the end of the integration period.
For discrete time systems, where s(t) and x(t) are sampled at ideal sampling points t k , Equation 3 can be written as:
ρ overall = ∑ k = 1 N S k · X k * 2 { ∑ k = 1 N S k 2 } · { ∑ k = 1 N X k 2 } ( 4 )
where:
X k =x[k]=x(t k ) is k th sample of the actual waveform; and
S k =s[k]=s(t k ) is the corresponding k th sample of the ideal waveform.
A multiple-access communication system may carry voice and/or data. An example of a communication system carrying both voice and data is a system in accordance with the IS-95 standard, which specifies transmitting voice and data over the communication link. A method for transmitting data in code channel frames of fixed size is described in detail in U.S. Pat. No. 5,504,773, entitled “METHOD AND APPARATUS FOR THE FORMATTING OF DATA FOR TRANSMISSION,” assigned to the assignee of the present invention and incorporated by reference herein. In accordance with the IS-95 standard, the data or voice is partitioned into code channel frames that are 20 milliseconds wide with data rates as high as 14.4 Kbps. Additional examples of communication systems carrying both voice and data comprise communication systems conforming to the “3rd Generation Partnership Project” (3GPP), embodied in a set of documents including Document Nos. 3G TS 25.211, 3G TS 25.212, 3G TS 25.213, and 3G TS 25.214 (the W-CDMA standard), or “TR-45.5 Physical Layer Standard for cdma2000 Spread Spectrum Systems” (the IS-2000 standard). Such communication systems use a waveform similar to the one discussed above.
Recently, a data only communication system for a high data rate (HDR) transmission has been developed. Such a communication system has been disclosed in co-pending application Ser. No. 08/963,386, entitled “METHOD and apparatus FOR HIGH RATE PACKET DATA transmission,” filed Nov. 3, 1997, now U.S. Pat. No. 6,574,211B2, issued on Jun. 3, 2003, assigned to the assignee of the present invention and incorporated by reference herein. The HDR communication system defines a set of data rates, ranging from 38.4 kbps to 2.4 Mbps, at which an origination terminal (access point, AP) may send data packets to a receiving terminal (access terminal, AT). The HDR system utilizes a waveform with channels distinguished both in time domain and code domain.
FIG. 2 illustrates such a waveform 200 , modeled after a forward link waveform of the above-mentioned HDR system. The waveform 200 is defined in terms of frames 202 . (Only frames 202 a , 202 b , and 202 c are shown in FIG. 2 .) In an exemplary embodiment, a frame comprises 16 time slots 204 , each time slot 204 being 2048 chips long, corresponding to a 1.67 millisecond slot duration, and, consequently, a 26.67 ms frame duration. Each slot 204 is divided into two half-slots 204 a and 204 b , with pilot bursts 206 a and 206 b transmitted within each half-slot 204 a and 204 b . In an exemplary embodiment, each pilot burst 206 a and 206 b is 96 chips long, and is centered at the mid-point of its associated half-slot 204 a and 204 b . The pilot bursts 206 a and 206 b comprise a pilot channel signal covered by a Walsh cover with index 0 . The pilot channel is used for synchronization purposes. A forward medium access control channel (MAC) 208 forms two bursts 208 a and two bursts 208 b of a length of 64 chips each. The MAC bursts 208 a and 208 b are transmitted immediately before and immediately after the pilot bursts 206 a and 206 b of each slot 204 . In an exemplary embodiment, the MAC is composed of up to 63 code channels, which are orthogonally covered by 64-ary Walsh codes. Each code channel is identified by a MAC index, which has a value between 0 and 63 and identifies the unique 64-ary Walsh cover. The MAC indexes 0 and 1 are reserved. A reverse power control channel (RPC) is used to regulate the power of the reverse link signals for each subscriber station. The RPC is assigned to one of the available MACs with MAC index 5 - 63 . The MAC with MAC index 4 is used for a reverse activity channel (RA), which performs flow control on a reverse traffic channel. The forward link traffic channel and control channel payload is sent in the remaining portions 210 a of the first half-slot 204 a and the remaining portions 210 b of the second half-slot 204 b . The forward traffic channel and control channel data are encoded, scrambled, and interleaved. The interleaved data are modulated, repeated, and punctured, as necessary. Then, the resulting sequences of modulation symbols are demultiplexed to form 16 pairs (in-phase and quadrature) of parallel streams. Each of the parallel streams is covered with a distinct 16-ary Walsh cover, yielding a code-distinguished channel 212 .
The ideal waveform 200 is then quadrature spreaded, baseband-filtered and upconverted on a carrier frequency. The resulting modulated waveform 200 , is expressed as:
s ( t ) = ∑ i ( t ) R i ( t ) ⅇ - j ω c t ( 5 )
where:
ω c is the nominal carrier frequency of the waveform;
i(t) is the index of the code channels. The index is time dependent as the number of code channels varies with time; and
R i (t) is the complex envelope of the ideal i-th code channel, given as:
R i ( t ) = a i [ ∑ k g ( t - kT c ) cos ( ϕ i , k ) + j ∑ k g ( t - kT c ) sin ( ϕ i , k ) ] ( 6 )
where:
a i is the amplitude of the ith code channel;
g(t) is the unit impulse response of the baseband transmit filter;
φ i,k is the phase of the kth chip for the ith code channel, occurring at discrete time t k =kT c .
T c is a chip duration.
The transmitter of the HDR communication system generates an actual waveform x(t), given as:
x ( t ) = ∑ i ( t ) b i [ R i ( t + τ i ) + E i ( t ) ] · ⅇ - j [ ( ω c + Δ ω ) ( t + τ i ) + θ i ] ( 7 )
where
b i is the amplitude of the ideal waveform relative to the ideal waveform for the i th code channel;
τ i is the time offset of the ideal waveform relative to the ideal waveform for the i th code channel;
Δω is the radian frequency offset of the signal;
θ i is the phase offset of the ideal waveform relative to the ideal waveform for the i th code channel; and
E i (t) is the complex envelope of the error (deviation from ideal) of the actual transmit signal for the i-th code channel.
Based on the complex time domain and code domain channelization of the waveform 200 , the waveform quality measurement methods based on code domain channelization are inapplicable. Consequently, there is a need in the art for a method and an apparatus for a waveform quality measurement for waveforms channelized both in time domain and code domain.
SUMMARY
The present invention is directed to a novel method and apparatus for waveform quality measurement. According to the method, an actual signal, representing a waveform divided into channels both in time domain and in code domain is generated. Such an actual waveform can be generated, for example, by a communication system. Test equipment generates an ideal waveform corresponding to the actual waveform. The test equipment then generates an estimate of offsets between parameters of the actual waveform and the ideal waveform, and uses the offsets to compensate the actual waveform. In one embodiment, overall modulation accuracy is evaluated in accordance with the compensated ideal waveform and the ideal waveform.
In another embodiment, modulation accuracy for a particular time division channel of the waveform is evaluated. The compensated actual waveform is processed to provide the particular time division channel. In one implementation, the processing comprises assigning the compensated actual signal a value that is non-zero in intervals where the particular time division channel is defined and non-zero elsewhere. In another implementation, the processing comprises a multiplication of the compensated actual waveform by a function with a value that is non-zero in intervals where the particular time division channel is defined and zero elsewhere. In one implementation, the ideal waveform is processed in the same manner. In another implementation, the ideal waveform containing the particular time division channel is generated directly. The modulation accuracy for the particular time division channel is evaluated in accordance with the processed compensated actual waveform and the processed ideal waveform.
In yet another embodiment, code domain power coefficients for a particular code channel are evaluated. The particular time division channel, which contains the particular code channel of the compensated actual waveform, is obtained according to the above-described methods. In one implementation, the ideal waveform is processed in the same manner. In another implementation, the ideal waveform containing the particular code channel of the particular time division channel is generated directly. The modulation accuracy for the particular time division channel is evaluated in accordance with the processed compensated actual waveform and the processed ideal waveform.
BRIEF DESCRIPTION OF THE DRAWINGS
The features, objects, and advantages of the present invention will become more apparent from the detailed description set forth below when taken in conjunction with the drawings in which like reference characters identify correspondingly throughout and wherein:
FIG. 1 illustrates an idealized waveform of a code division communication system;
FIG. 2 illustrates an idealized waveform of an HDR communication system; and
FIG. 3 illustrates a concept of an apparatus capable of implementing waveform quality measurement in accordance with the principles of this invention.
DETAILED DESCRIPTION
FIG. 3 illustrates a concept of an apparatus capable of implementing waveform quality measurement for waveforms channelized both in time domain and in code domain, such as the exemplary waveform 200 from FIG. 2 .
In one embodiment, actual signal x(t) (representing waveform 200 from FIG. 2 ) enters compensation block 302 . The compensation block 302 is also provided with estimates of offsets of the actual waveform x(t) with respect to an ideal waveform s(t) from an optimization block 304 . The compensation block 302 uses the offset estimates to provide a compensated waveform y(t). The compensated waveform y(t) is provided to a downconversion block 306 . The downconverted signal is then provided to an optional sampling block 308 . The sampled waveform zs[k] is provided to an optional baseband transformation block 310 . The output waveform z[k] from the optional baseband transformation block 310 is provided to a processing block 312 .
In one embodiment, the ideal waveform s(t) is generated by a signal generator 314 . The ideal waveform s(t) is provided to an optional sampling block 316 . The sampled waveform ss[k] is provided to an optional baseband transformation block 318 . The output waveform r[k] from the optional baseband transformation block 318 is provided to a processing block 312 . In another embodiment, the signal generator 314 generates the digital waveform r[k] directly. Therefore, in such an embodiment, the sampling block 316 and the optional baseband transformation block 318 are not needed.
The processing block 312 uses signals z[k] and r[k] to calculate waveform characteristics.
As discussed, the actual waveform x(t) will be offset from the ideal waveform s(t) in frequency, time and phase. The waveform quality measurement is determined for the best alignment between the actual waveform x(t) will be offset from the ideal waveform s(t). Consequently, the waveform quality measurement is evaluated for a plurality of combinations of frequency, time, and phase offsets, and the maximum of such evaluations is taken as a figure of merit. The function of optimization block 304 is to generate the plurality of combinations of frequency, time, and phase offsets.
The function of the compensation block 302 is to operate on the waveform x(t) to provide compensated waveform y(t), given by Equation 7:
y ( t )= x ( t−{circumflex over (τ)} 0 ) e j[Δ{circumflex over (ω)}·t+{circumflex over (θ)} 0 ] (8)
where:
Δ{circumflex over (ω)}—an estimate of radian frequency offset of the signal x(t) with respect to signal s(t);
{circumflex over (τ)} 0 —an estimate of time offset of the signal x(t) with respect to signal s(t);
{circumflex over (θ)} 0 —an estimate of phase offset of the signal x(t) with respect to signal s(t).
The Δ{circumflex over (ω)}, {circumflex over (τ)} 0 , {circumflex over (θ)} 0 , are provided to the compensation block 302 by the optimization block 304 .
As discussed, the waveform x(t) was upconverted on a carrier frequency, the purpose of the downconversion block 306 is to downconvert the compensated waveform y(t) to a baseband waveform z(t).
In one embodiment, the optional sampling block 308 creates discrete version z[k] of the waveform z(t) by sampling the waveform z(t) at the ideal sampling points t k :
z[k]=z ( t k ); ∀ k (9)
In another embodiment, the optional sampling block 308 is omitted and the sampling is performed by the processing block 312 after baseband transformation.
As discussed, the waveform 200 is baseband filtered before transmission. Consequently, the optional baseband transformation block 310 is utilized to remove inter-symbol interference (ISI) introduced by the transmitter filter. To accomplish this, the transfer function of the baseband transformation block 310 is an inverse complex conjugate of the transfer function of the ideal transmitter filter.
The processing block 312 operates on the signals z[k] and r[k] to provide the required waveform quality measurement as described in detail below. In one embodiment, when the optional sampling block 308 has been omitted, the processing block 312 creates a discrete z[k] version of the signal z(t) by sampling the signal z(t) at the ideal sampling points tk in accordance with Equation 9.
Considering the above-described apparatus, one of ordinary skills in the art will be able to modify the block schematics to different representation of the waveforms x(t) and s(t). For example, if the waveform x(t) is represented as a baseband signal in a digital domain, a downconversion block 306 and an optional sampling block 308 need not be present. Furthermore, if the waveform x(t) has not been filtered, an optional baseband transformation block 310 need not be present. Furthermore, one of ordinary skills in the art will be able to modify the block schematics according to a type of measurement to be performed. For example, if an effect of a baseband filter is to be ascertained, the baseband transformation blocks 310 and 318 would be omitted; thus, the processing block 312 would be provided with the ideal waveform and the ideal waveform from sampling blocks 308 and 316 .
Modulation Accuracy Measurement
Modulation accuracy is defined as a fraction of power in the actual waveform z[k] that correlates with the ideal waveform r[k], when the transmitter is modulated by at least one channel in the waveform.
An overall modulation accuracy is defined as a fraction of power in the actual waveform z[k] that correlates with the ideal waveform r[k] when the transmitter is modulated by all the channels in the waveform. In the exemplary embodiment of the HDR communication system, these channels comprise the Pilot Channel, the MAC Channel and the Forward Traffic or Control Channel. The first overall modulation accuracy is defined as follows:
ρ overall - 1 = N · ∑ j = 1 N ∑ k = 1 M Z j , k R j , k * 2 { ∑ j = 1 N ∑ k = 1 M R j , k 2 } · { ∑ j = 1 N ∑ k = 1 M Z j , k 2 } ( 10 )
where:
ρ overall−1 is the first overall modulation accuracy;
j is an index designating an elementary unit of a waveform;
N is a summation limit designating number of elementary units;
k is an index designating a sample in the elementary unit;
M is a summation limit designating number of samples in the elementary unit;
Z j,k =z[M(j−1)+k] is a k th sample in the j th elementary unit of the actual waveform; and
R j,k =r[M(j−1)+k] is a kth sample in the ith elementary unit of the ideal waveform.
An elementary unit is defined as a minimum waveform span defining a complete channel structure. The value of the summation limit N is chosen so that a noise variance of the measurement is below a required value.
Applying Equation 10 to the waveform 200 of a forward link of the HDR system, the elementary unit is a half-slot; consequently, the summation limit M=1024. The first sample, z(t1), occurs at the first chip of a half slot and the final sample, z(t1024N), occurs at the last chip of a half slot. The value of the summation limit N has been determined to be at least 2.
The first overall modulation accuracy fails to account for possible discontinuities of parameters of the waveform on the borders of the elementary units. Consequently, a second overall modulation accuracy is defined as follows:
ρ overall - 2 = N · ∑ j = 1 N ∑ k = M 2 + 1 M + M 2 + 1 Z j , k R j , k * 2 { ∑ j = 1 N ∑ k = M 2 + 1 M + M 2 + 1 R j , k 2 } · { ∑ j = 1 N ∑ k = M 2 + 1 M + M 2 + 1 Z j , k 2 } ( 11 )
where:
ρ overall−2 is the second overall modulation accuracy;
j is an index designating an elementary unit of a waveform;
N is a summation limit designating number of elementary units;
k is an index designating a sample in the elementary unit;
M is a summation limit designating number of samples in the elementary unit;
Z j , k = z [ ( M + M 2 + 1 ) · ( j - 1 ) + k ]
is a k th sample in the j th elementary unit of the actual waveform; and
R j , k = r [ ( M + M 2 + 1 ) · ( j - 1 ) + k ]
is a k th sample in the j th elementary unit of the ideal waveform.
Applying Equation 11 to the waveform 200 of a forward link of the HDR system, the elementary unit is a half-slot; consequently, the summation limit M=1024. The first sample, z(t 531 ), occurs at the 513th chip of a half slot and the final sample, z(t1536N), occurs at the 513th chip of the last half slot. The value of the summation limit N has been determined to be at least 2.
A time division channel (TD_channel) modulation accuracy is defined as a fraction of power in the actual waveform z[k] that correlates with the ideal waveform r[k] when the transmitter is modulated by the particular TD_channel in the waveform. In the exemplary embodiment of the HDR communication system, the channels comprise the Pilot Channel, the MAC Channel and the Forward Traffic or Control Channel. The TD_channel modulation accuracy is defined as follows:
ρ TD_channel = N · ∑ j = 1 N ∑ k = 1 M Z j , k R j , k * 2 { ∑ j = 1 N ∑ k = 1 M R j , k 2 } · { ∑ j = 1 N ∑ k = 1 M Z j , k 2 } ( 12 )
where:
ρ TD — channel is the modulation accuracy for the time division channel identified by an index TD_channel;
j is an index designating an elementary unit of a waveform;
N is a summation limit designating number of elementary units;
k is an index designating a sample in the elementary unit;
M is a summation limit designating number of samples in the elementary unit;
Z j,k =z[M(j−1)+k] is a k th sample in the j th elementary unit of the actual TD_channel; and
R j,k =r[M(j−1)+k] is a kth sample in the j th elementary unit of the ideal TD_channel.
The concept of processing the actual waveform z[k] and the ideal waveform r[k] to obtain a particular TD_channel is described next. A function g TD — channel is defined:
g TD_channel [ k ] = { 1 if { m 1 ≤ ( k mod L ) ≤ m 2 m 3 ≤ ( k mod L ) ≤ m 4 ⋮ m n - 1 ≤ ( k mod L ) ≤ m n 0 elsewhere ( 13 )
where:
m p ≦(k mod L≦m p+1 ) for p=1,2, . . . n, defines intervals where the waveform is nonzero for the particular TD_channel; and
L interval of an elementary unit of the signal z[k].
Then, the actual waveform z[k] and the ideal waveform r[k] are multiplied by the function g TD — channel [k], to yield the particular TD_channels:
z′[k]=z[k]·g TD — channel [k]
r′[k]=r[k]·g TD — channel [k] (14)
One of ordinary skills in the art will understand that the implementation of the concept can vary. In one embodiment, the processing is implemented as a multiplication of the waveform by a function with a value that is non-zero in intervals where the particular time division channel is defined and zero elsewhere. In another embodiment, the processing comprises assigning the waveform a value that is non-zero in intervals to where the particular time division channel and zero elsewhere. In yet another embodiment, the processing unit, implementing Equation (12) is configured to carry the internal summations as follows:
∑ k = 1 M = ∑ m 1 m 2 + ∑ m 3 m 4 + … + ∑ m n - 1 m n ( 15 )
where:
m p ≦(k mod L≦m p+1 ) for p=1,2, . . . n, defines interval where the waveform is nonzero for the particular TD_channel; and
L interval of an elementary unit of the signals z[k] and r[k].
Code Domain Measurement
Code domain power is defined as a fraction of power of the signal z(t k ) that correlates with each code channel R i (t k ) when the transmitter is modulated according to a known code symbol sequence. The concept of processing the waveform to obtain each code channel R i (t k ) is described next. First, a particular TD_channel containing each code channel R i (t k ) is obtained, utilizing any of the above-outlined methods. For example, Equation 13 is used to obtain function g TD — channel [k] for the particular TD_channel. The function g TD — channel [k] is then used to operate on the actual waveform z[k] and the i-th code channel R i [k] of the ideal signal r[k] to obtain waveforms:
z′[k]=z[k]·g TD — channel [k]
R i ′[k]=R i [k]·g TD — channel [k] (16)
The waveform quality code domain power coefficients ρTD_channel,i for the particular TD_channel are then defined for each code channel R i (t k ) as follows:
ρ TDM_channel , i = N · ∑ j = 1 N ∑ k = 1 M Z j , k R i , j , k ′ * 2 { ∑ j = 1 N ∑ k = 1 M R i , j , k ′ 2 } · { ∑ j = 1 N ∑ k = 1 M Z j , k 2 } , i = w 1 , … , w v ( 17 )
where:
ρ TDM — channel,i is the code domain coefficient for a time division channel identified by an index TD_channel and a code channel R i [k] identified by index i;
w 1 is a first code channel for the time division channel TDM_channel;
w v is a last code channel for time division channel TDM_channel;
j is an index designating an elementary unit of waveforms;
N is a summation limit designating a number of elementary units;
k is an index designating a sample in the elementary unit;
M is a summation limit designating number of samples in the elementary units;
Z j,k =Z[M(j−1)+k] is a kth sample in the jth elementary unit of the filtered signal; and
R′ i,j,k =R′ i [M(j−1)+k] is a kth sample in the jth elementary unit of the i-th code channel of the ideal signal.
For example, applying the above-described method to evaluate ρ MAC,i , of the waveform 200 of a forward link of the HDR system, the elementary unit is a half-slot; consequently, the summation limit M=1024. From Equation (13) and FIG. 2 :
g MAC [ k ] = { 1 if { 401 ≤ ( k mod 1024 ) ≤ 464 561 ≤ ( k mod 1024 ) ≤ 624 0 elsewhere ( 18 )
where (k mod 1024)=1 occurs at the first chip of every half slot. Then, Equation (16) yields:
z′[k]=z[k]·g MAC [k] R i ′[k]=R i [k]·g MAC [k] (19)
The following code domain power coefficients ρ MAC,i are defined for the MAC Channel by Equation (17):
ρ
MAC
,
i
=
N
·
∑
j
=
1
N
∑
k
=
1
1024
Z
j
,
k
″
R
i
,
j
,
k
″
*
2
{
∑
j
=
1
N
∑
k
=
1
1024
R
i
,
j
,
k
″
2
}
·
{
∑
j
=
1
N
∑
k
=
1
1024
Z
j
,
k
″
2
}
,
i
=
2
,
…
,
63
(
20
)
The value of N for the measurement of ρ MAC,i for i≠4 has been determined to be at least 16. The first sample, z(t 1 ), occurs at the first chip of a half slot and the final sample, z(t 1024N ), occurs at the last chip of a half slot.
Those of skill in the art would understand that the various illustrative logical blocks, modules, circuits, and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, computer software, or combinations of both. The various illustrative components, blocks, modules, circuits, and steps have been described generally in terms of their functionality. Whether the functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system. Skilled artisans recognize the interchangeability of hardware and software under these circumstances, and how best to implement the described functionality for each particular application.
As examples, the various illustrative logical blocks, modules, circuits, and algorithm steps described in connection with the embodiments disclosed herein may be implemented or performed with 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, such as, e.g., registers and FIFO, a processor executing a set of firmware instructions, any conventional programmable software module and a processor, or any combination thereof. The processor may advantageously be a microprocessor, but in the alternative, the processor may be any conventional processor, controller, microcontroller, or state machine. The software module could reside in RAM memory, flash memory, ROM memory, registers, hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art. Those of skill would further appreciate that the data, instructions, commands, signals, bits, symbols, and chips that may be referenced throughout the above description are advantageously represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.
The previous description of the preferred embodiments, using communication systems to exemplify measurement of waveform quality, is provided to enable any person skilled in the art to make or use the present invention. The various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without the use of the inventive faculty. Specifically, one of ordinary skills in the art will understand that the generic principles disclosed apply equally to any like waveform regardless of the equipment that generated the waveform. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
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A method and an apparatus for waveform quality measurement are disclosed. An actual signal, representing a waveform channelized both in time and in code is generated by, e.g., an exemplary HDR communication system. Test equipment generates an ideal waveform corresponding to the actual waveform. The test equipment then generates an estimate of offsets between parameters of the actual waveform and the ideal waveform, and the offsets are used to compensate the actual waveform. The test equipment then evaluates various waveform quality measurements utilizing the compensated actual waveform and the corresponding ideal waveform. Definitions of the various waveform quality measurements as well as conceptual and practical examples of processing of the actual waveform and the corresponding ideal waveform by the test equipment are disclosed. The disclosed method and apparatus may be extended to any waveform channelized both in time and in code regardless of the equipment that generated the waveform.
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COPYRIGHT NOTICE
©2007 Electro Scientific Industries, Inc. A portion of the disclosure of this patent document contains material that is subject to copyright protection. The copyright owner has no objection to the facsimile reproduction by anyone of the patent document or the patent disclosure, as it appears in the Patent and Trademark Office patent file or records, but otherwise reserves all copyright rights whatsoever. 37 CFR § 1.71(d).
TECHNICAL FIELD
The present disclosure relates to specimen processing systems and, in particular, to stage architecture for control of two- or three-dimensional positioning of a processing device relative to a target specimen.
BACKGROUND INFORMATION
Wafer transport systems configured for use in semiconductor wafer-level processing typically include a stage having a chuck that secures the wafer for processing. Sometimes the stage is stationary, and sometimes it is moveable. Some applications require that the stage move linearly in one, two, or three Cartesian dimensions, with or without rotation. The speed of the stage motion can dictate the throughput of the entire wafer processing platform if a significant amount of the total process time is spent aligning and transporting the wafer.
For applications including optical processing, a moveable optics assembly can be mounted above the wafer surface, thereby minimizing the wafer transport distances required. The primary direction of stage motion is referred to as the “major axis,” and the direction of stage motion perpendicular to the primary direction is referred to as the “minor axis.” The chuck holding the wafer, or specimen, to be processed may be mounted to a major axis stage for movement along the major axis, a minor axis stage for movement along the minor axis, or in stationary position below the major and minor axes. The major axis stage may support the minor axis stage, or they may be independent of each other.
Stage design of such optical systems is becoming more critical as electrical circuit dimensions shrink. One stage design consideration is the impact of process quality stemming from vibrational and thermal stability of the wafer chuck and optics assembly. In the case in which the laser beam position is continually adjusted, state-of-the-art structures supporting the laser assembly are too flexible to maintain the required level of precision. Moreover, as circuit dimensions shrink, particle contamination becomes of greater concern.
SUMMARY OF THE DISCLOSURE
A “split axis stage” architecture is implemented as a multiple stage positioning system that, in a preferred embodiment, supports a laser optics assembly and a workpiece having a surface on which a laser beam is incident for laser processing. The multiple stage positioning system is capable of vibrationally and thermally stable material transport at high speed and rates of acceleration. A “split axis” design decouples driven stage motion along two perpendicular axes lying in separate, parallel planes. In a preferred embodiment, motion in the horizontal plane is split between a specimen (major axis or lower) stage and a scan optics assembly (minor axis or upper) stage that move orthogonally relative to each other.
A dimensionally stable substrate in the form of a granite, or other stone slab, or a slab of ceramic material, cast iron, or polymer composite material such as Anocast™, is used as the base for the lower and upper stages. The slab and the stages are preferably fabricated from materials with similar coefficients of thermal expansion to cause the system to advantageously react to temperature changes in a coherent fashion. The substrate is precisely cut (“lapped”) such that portions of its upper and lower stage surfaces are flat and parallel to each other. In a preferred embodiment, a lower guide track assembly that guides a lower stage carrying a specimen-holding chuck is coupled to a lower surface of the substrate. An upper guide track assembly that guides an upper stage carrying a laser beam focal region control subsystem is coupled to an upper surface of the substrate. Linear motors positioned along adjacent rails of the guide track assemblies control the movements of the lower and upper stages.
The massive and structurally stiff substrate isolates and stabilizes the motions of the laser optics assembly and the specimen, absorbs vibrations, and allows for smoother acceleration and deceleration because the supporting structure is inherently rigid. The stiffness of the substrate and close separation of the stage motion axes result in higher frequency resonances, and less error in motion along all three axes. The substrate also provides thermal stability by acting as a heat sink. Moreover, because it is designed in a compact configuration, the system is composed of less material and is, therefore, less susceptible to expansion when it undergoes heating. An oval slot cut out of the middle of the substrate exposes the specimen below to the laser beam and allows for vertical motion of the laser optics assembly through the substrate. Otherwise, the specimen is shielded by the substrate from particles generated by overhead motion, except for the localized region undergoing laser processing.
A laser beam focal region control subsystem is supported above the lower stage and includes a vertically adjustable optics assembly positioned within a rigid air bearing sleeve mounted to the upper stage by a support structure. The rigidity of the support structure allows for faster and more accurate vertical motion along the beam axis. The inner surface of the sleeve acts as an outer race, and the outer surface of the lens acts as an inner race, thus forming an air bearing guiding the vertical motion of the focal region of the laser beam. Vertical motion is initiated by a lens forcer residing at the top end of the sleeve, which imparts a motive force to the optics assembly to adjust its height relative to the workpiece on the lower chuck, and in so doing, adjusts the focal region of the laser relative to the work surface. An isolation flexure device, rigid along the beam axis and compliant in the horizontal plane, buffers excess motion of the lens forcer from the optics assembly.
The split axis stage design is applicable to many platforms used in semiconductor processing including dicing, component trim, fuse processing, inking, printed wire board (PWB) via drilling, routing, inspection, and metrology. The advantages afforded by such a design are also of benefit to a whole class of mechanical machining tools.
Additional aspects and advantages will be apparent from the following detailed description of preferred embodiments, which proceeds with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an isometric view of a decoupled, multiple stage positioning system.
FIG. 2 is a partly exploded isometric view of the positioning system of FIG. 1 , showing upper and lower stages that, when the system is assembled, are mounted to a dimensionally stable substrate such as a stone slab.
FIG. 3 is an isometric view of the positioning system of FIG. 1 , showing the upper stage supporting a scan lens and upper stage drive components.
FIG. 4 is an isometric view of the positioning system of FIG. 1 , showing the lower stage supporting a specimen-holding chuck and lower stage drive components.
FIGS. 5A , 5 B, and 5 C are diagrams showing alternative guide track assembly configurations for moving one or both of the upper and lower stages of the positioning system of FIGS. 1-4 .
FIG. 6 is an exploded view of a preferred embodiment of a laser beam focal region control subsystem that includes an air bearing sleeve assembly housing a scan lens and guiding its vertical (Z-axis) motion.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
FIGS. 1 and 2 show a decoupled, multiple stage positioning system 10 , which, in a preferred embodiment, supports components of a laser processing system through which a laser beam propagates for incidence on a target specimen. Positioning system 10 includes a dimensionally stable substrate 12 made of a stone slab, preferably formed of granite, or a slab of ceramic material, cast iron, or polymer composite material such as Anocast™. Substrate 12 has a first or upper flat major surface 14 and a second or lower flat major surface 16 that has a stepped recess 18 . Major surfaces 14 and 16 include surface portions that are plane parallel to each other and conditioned to exhibit flatness and parallelism within about a ten micron tolerance.
A surface portion of upper major surface 14 and a first guide track assembly 20 are coupled to guide movement of a laser optics assembly stage 22 along a first axis, and a surface portion of lower major surface 16 and a second guide track assembly 24 are coupled to guide movement of a specimen stage 26 along a second axis that is transverse to the first axis. Optics assembly stage 22 supports a laser beam focal region control subsystem 28 , which includes a scan lens 30 that depends downwardly below lower major surface 16 of substrate 12 . Specimen stage 26 supports a specimen-holding chuck 32 . The guided motions of stages 22 and 26 move scan lens 30 relative to laser beam processing locations on a surface of a specimen (not shown) held by chuck 32 .
In a preferred implementation, substrate 12 is set in place so that major surfaces 14 and 16 define spaced-apart horizontal planes and guide track assemblies 20 and 24 are positioned so that the first and second axes are perpendicular to each other and thereby define respective Y- and X-axes. This split axis architecture decouples motion along the X- and Y-axes, simplifying control of positioning the laser beam and chuck 32 , with fewer degrees of freedom allowed.
FIG. 3 shows in detail optics assembly stage 22 , which operates with first guide track assembly 20 shown in FIG. 2 . First guide track assembly 20 includes two spaced-apart guide rails 40 secured to support portions of upper major surface 14 and two U-shaped guide blocks 42 supported on a bottom surface 44 of optics assembly stage 22 . Each one of guide blocks 42 fits over and slides along a corresponding one of rails 40 in response to an applied motive force. A motor drive for optics assembly stage 22 includes a linear motor 46 that is mounted on upper major surface 14 and along the length of each guide rail 40 . Linear motor 46 imparts the motive force to propel its corresponding guide block 42 for sliding movement along its corresponding guide rail 40 . Each linear motor 46 includes a U-channel magnet track 48 that holds spaced-apart linear arrays of multiple magnets 50 arranged along the length of guide rail 40 . A forcer coil assembly 52 positioned between the linear arrays of magnets 50 is connected to bottom surface 44 of optics assembly stage 22 and constitutes the movable member of linear motor 46 that moves optics assembly stage 22 . A suitable linear motor 46 is a Model MTH480, available from Aerotech, Inc., Pittsburgh, Pa.
Each rail guide 40 -guide block 42 pair of first guide track assembly 20 shown in FIG. 2 is a rolling element bearing assembly. Alternatives for guide track assembly 20 include a flat air bearing or a vacuum preloaded air bearing. Use of either type of air bearing entails removal of each guide rail 40 , exposing the surface portions of upper surface 14 to form guide surfaces, and substitution for each guide block 42 the guide surface or bearing face of the bearing, which is attached to bottom surface 44 of laser optics assembly stage 22 . Vacuum preloaded air bearings, which have a pressure port and a vacuum port, hold themselves down and lift themselves off the guide surface at the same time. Use of vacuum preloaded air bearings needs only one flat guide surface; whereas use of opposed bearing preloading needs two flat, parallel guide surfaces. Suitable air bearings are available from New Way Machine Components, Inc., Aston, Pa. Thus, depending on the type of guide track assembly used, surface portions of upper major surface 14 may represent a guide rail mounting contact surface or a bearing face noncontacting guide surface.
A pair of encoder heads 60 secured to bottom surface 44 of optics assembly stage 22 and positioned adjacent different ones of guide blocks 42 includes position sensors that measure yaw angle and distance traveled of optics assembly stage 22 . Placement of the position sensors in proximity to guide rails 40 , guide blocks 42 , and linear motors 46 driving each of stages 22 and 26 ensures efficient, closed-loop feedback control with minimal resonance effects. A pair of stop members 62 limits the travel distance of guide blocks 42 in response to limit switches included in encoder heads 60 that are tripped by a magnet (not shown) attached to substrate 12 . A pair of dashpots 64 dampen and stop the motion of optics assembly stage 22 to prevent it from overtravel movement off of guide rails 40 .
An oval slot 66 formed in substrate 12 between and along the lengths of guide rails 40 provides an opening within which scan lens 30 can travel as optics assembly stage 22 moves along guide rails 40 . A pair of through holes 68 formed in the region of stepped recess 18 in substrate 12 provides operator service access from upper surface 14 to encoder heads 60 to maintain their alignment.
FIG. 4 shows in detail specimen stage 26 in operative association with second guide track assembly 24 of FIG. 2 . Second guide track assembly 24 includes guide rails, U-shaped guide blocks, linear motors, U-channel magnet tracks, magnets, forcer coil assemblies, and encoder heads that correspond to and are identified by the same reference numerals as those described above in connection with first guide track assembly 20 . Linear motors 46 and the components of and components supported by second guide track assembly 24 are mounted on a surface 70 of a specimen stage bed 72 .
The mechanical arrangement of stages 22 and 26 and motors 46 results in reduced pitch and roll of stages 22 and 26 , and enhances accuracy of high velocity motion. Symmetric placement of motors 46 on opposite sides of stages 22 and 26 improves control of yaw. The placement of motors 46 along the sides of stages 22 and 26 , as opposed to underneath them, minimizes thermal disturbance of critical components and position sensors.
Second guide track assembly 24 and specimen stage 26 supporting chuck 32 fits into and is secured within stepped recess 18 . Surface 70 of specimen stage bed 72 is secured against a surface portion 74 of lower major surface 16 adjacent the wider, lower portion of stepped recess 18 , and chuck 32 is positioned below the innermost portion of stepped recess 18 of lower major surface 16 and moves beneath it in response to the motive force imparted by linear motors 46 moving specimen stage 26 along second guide track assembly 24 . A pair of stop members 76 limits the travel distance of guide blocks 42 in response to limit switches included in encoder heads 60 that are tripped by a magnet (not shown) attached to substrate 12 . A pair of dashpots 78 dampen and stop the motion of specimen stage 26 to prevent it from overtravel movement off of guide rails 40 .
A first alternative to guide track assembly 24 is a magnetic preloaded air bearing using specimen stage bed 72 as a bearing land or guideway. Use of a magnetic preloaded air bearing entails removal of each guide rail 40 , exposing the surface portions of specimen stage bed 72 , and the removal of each guide block 42 , providing on the bottom surface of specimen stage 26 space for mounting the air bearing with its (porous) bearing face positioned opposite the exposed surface portion.
FIG. 5A is a schematic diagram showing the placement of two magnetic preloaded air bearings 100 in the this first alternative arrangement. A steel plate, or steel laminate structure 102 , is fixed on surface 70 in the space between and along the lengths of forcer coil assemblies 52 . Two spaced-apart flat air bearings 100 are fixed to corresponding surface portions 104 of a bottom surface 106 of specimen stage 26 and run along the lengths of linear motors 46 . A suitable air bearing is a silicon carbide porous media flat bearing series Part No. S1xxxxx, available from New Way Machine Components, Inc., Aston, Pa. A sheet magnet 108 is positioned in the space between air bearings 100 on bottom surface 106 of specimen stage 26 and spatially aligned with steel plate 102 so that the exposed surfaces of magnet 108 and steel plate 102 confront each other. The magnetic force of attraction urges sheet magnet 108 downwardly toward steel plate or steel laminate 102 as indicated by the downward pointing arrow in FIG. 5A , and the net force of air bearings 100 urges specimen stage 26 upwardly away from surface 70 from specimen stage bed 72 , as indicated by two parallel upward pointing arrows in FIG. 5A . The simultaneous application of opposed magnetic force and pressurized air creates a thin film of air in spaces 110 between (porous) bearing faces 112 of air bearings 100 and bearing guideways 114 on surface 70 . The lift force of air bearings 100 equals twice the sum of the weight of specimen stage 26 and the magnetic force of magnet 108 . Linear motors 46 impart the motive force that results in nearly zero friction motion of specimen stage 26 along the lengths of bearing guideways 114 .
A second alternative to guide track assembly 24 is a vacuum preloaded air bearing using specimen stage bed 72 as a bearing land or guideway. Similar to the above-described first alternative to guide track assembly 20 , use of a vacuum preloaded air bearing entails removal of each guide rail 40 , exposing surface portion 114 of specimen stage bed 72 , and the removal of each guide block 42 , providing on bottom surface 106 of specimen stage 26 space for mounting the vacuum loaded air bearing, with its pressure land positioned opposite exposed surface portion 114 .
FIG. 5B is a schematic diagram showing the placement of two vacuum preloaded air bearings 120 in the second alternative arrangement. Two spaced-apart vacuum preloaded air bearings 120 are fixed to corresponding surface portions 104 of bottom surface 106 of specimen stage 26 and run along the lengths of linear motors 46 . A suitable air bearing is a vacuum preloaded air bearing series Part No. S20xxxx, available from New Way Machine Components, Inc., Aston, Pa. Vacuum preloaded bearings 120 simultaneously hold themselves down and lift themselves off bearing guideways 114 on surface 70 . Each vacuum preloaded bearing 120 has a pressure land that is divided into spaced-apart land portions 122 a and 122 b . A vacuum area 124 is located between land portions 122 a and 122 b . The simultaneous application and distribution of air pressure and vacuum pressure creates a thin film of air in spaces 126 between pressure land portions 122 a and 122 b of vacuum preloaded air bearings 120 and bearing guideways 114 on surface 70 . Linear motors 46 impart the motive force that results in nearly zero friction motion of specimen stage 26 along the lengths of the bearing guideways 114 .
A third alternative to guide track assembly 24 entails the use of either a magnetic preloaded air bearing of the first alternative, or a vacuum preloaded air bearing of the second alternative in the absence of specimen stage bed 72 , as well as each guide rail 40 and each guide block 42 .
FIG. 5C is a schematic diagram showing specimen stage 26 riding on magnetic preloaded air bearings or vacuum preloaded air bearings 140 along bottom surface 142 of substrate 12 . When substrate 12 is in a horizontal disposition, magnetic preloaded or vacuum preloaded air bearings 140 develop sufficient force to overcome the gravitational force on specimen stage 26 as it rides along bottom surface 142 . Skilled persons will appreciate that laser optics assembly stage 22 can similarly be adapted to ride on magnetic preloaded air bearings or vacuum preloaded air bearings along upper major surface 14 of substrate 12 . The stage configuration can use mechanical linear guides in place of the air bearings described above. Other devices for measuring position, such as interferometers, can be implemented in this positioning system design.
The mass of substrate 12 is sufficient to decouple the mass of optics assembly stage 22 and the mass of specimen stage 26 , including the specimen mounted on it, so that the guided motion of one of stages 22 and 26 contributes a negligible motive force to the other one of them. The masses of stages 22 and 26 moving along the X- and Y-axes are low, and thereby allow high acceleration and high velocity processing and limit heat generation in linear motors 46 . Because the center of mass of the laser beam focal region control subsystem 28 is aligned with the center of mass of optics assembly stage 22 , perturbations in the motion of optics assembly stage 22 are minimized.
Laser optics assembly stage 22 has an opening 200 that receives control subsystem 28 , which includes an air bearing assembly 202 containing scan lens 30 . Control subsystem 28 controls the axial position of a laser beam focal region formed by scan lens 30 as the laser beam propagates generally along a beam axis 206 , which is the optic axis of scan lens 30 , and through scan lens 30 for incidence on a work surface of a target specimen supported on specimen stage 26 .
FIG. 6 shows in greater detail the components of control subsystem 28 and its mounting on laser optics assembly stage 22 . With reference to FIG. 6 , control subsystem 28 includes a lens forcer assembly 210 that is coupled by a yoke assembly 212 to scan lens 30 contained in the interior of an air bushing 214 of air bearing assembly 202 . A suitable air bushing is Part No. S307501, available from New Way Machine Components, Inc., Aston, Pa. Lens forcer assembly 210 , which is preferably a voice coil actuator, imparts by way of yoke assembly 212 a motive force that moves scan lens 30 and thereby the focal region of the laser beam to selected positions along beam axis 206 .
Voice coil actuator 210 includes a generally cylindrical housing 230 and an annular coil 232 formed of a magnetic core around which copper wire is wound. Cylindrical housing 230 and annular coil 232 are coaxially aligned, and annular coil 232 moves axially in and out of housing 230 in response to control signals (not shown) applied to voice coil actuator 210 . A preferred voice coil device 210 is an Actuator No. LA 28-22-006 Z, available from BEI Kimco Magnetics, Vista, Calif.
Annular coil 232 extends through a generally circular opening 234 in a voice coil bridge 236 having opposite side members 238 that rest on uprights 240 ( FIG. 1 ) mounted on laser optics assembly stage 22 to provide support for laser beam focal region control subsystem 28 . Voice coil bridge 236 includes in each of two opposite side projections 242 a hole 244 containing a tubular housing 250 through which passes a rod 252 extending from an upper surface 254 of a guiding mount 256 . Each rod 252 has a free end 258 . Guiding mount 256 has on its upper surface 254 an annular pedestal 260 on which annular coil 232 rests. Two stacked, axially aligned linear ball bushings 264 fit in tubular housing 250 contained in each hole 244 of side projections 242 of voice coil bridge 236 . Free ends 258 of rods 252 passing through ball bushings 264 are capped by rod clamps 266 to provide a hard stop of lower travel limit of annular coil 232 along beam axis 206 .
Housing 230 has a circular opening 270 that is positioned in coaxial alignment with the center of annular coil 232 , opening 234 of voice coil bridge 236 , and the center of annular pedestal 260 of guiding mount 256 . A hollow steel shaft 272 extends through opening 270 of housing 230 , and a hexagonal nut 274 connects in axial alignment hollow steel shaft 272 and a flexible tubular steel member 276 , which is coupled to yoke assembly 212 as further described below. Hexagonal nut 274 is positioned in contact with a lower surface 278 of annular coil 232 to drive flexible steel member 276 along a drive or Z-axis 280 in response to the in-and-out axial movement of annular coil 232 . Hollow steel shaft 272 passes through the center and along the axis of a coil spring 282 , which is confined between a top surface 284 of housing 230 and a cylindrical spring retainer 286 fixed at a free end 290 of hollow steel shaft 272 . Coil spring 282 biases annular coil 232 to a mid-point of its stroke along Z-axis 280 in the absence of a control signal applied to voice coil actuator 210 .
Yoke assembly 212 includes opposed yoke side plates 300 (only one shown) secured at one end 302 to a surface 304 of a yoke ring 306 and at the other end 308 to a multilevel rectangular yoke mount 310 . Scan lens 30 formed with a cylindrical periphery 312 and having an annular top flange 314 fits in yoke assembly 212 so that top flange 314 rests on surface 304 of yoke ring 306 . Scan lens 30 contained in the interior of air bushing 214 forms the inner race of air bearing assembly 202 , and an inner surface 316 of air bushing 214 forms the outer race of air bearing assembly 202 . The implementation of air bearing assembly 202 increases the rigidity of scan lens 30 in the X-Y plane but allows scan lens 30 to move along the Z-axis in a very smooth, controlled manner.
Flexible steel member 276 has a free end 320 that fits in a recess 322 in an upper surface 324 of yoke mount 310 to move it along Z-axis 280 and thereby move scan lens 30 along beam axis 206 . An encoder head mount 326 holding an encoder 328 and attached to voice coil bridge 236 cooperates with an encoder body mount 330 holding an encoder scale and attached to guiding mount 256 to measure, using light diffraction principles, the displacement of guiding mount 256 relative to voice coil bridge 236 in response to the movement of annular coil 232 . Because flexible tubular steel member 276 is attached to annular coil 232 , the displacement measured represents the position of scan lens 30 along beam axis 206 .
A quarter-waveplate 340 secured in place on a mounting ring 342 is positioned between a lower surface 344 of rectangular yoke mount 310 and top flange 314 of scan lens 30 . A beam deflection device 346 , such as a piezoelectric fast steering mirror, attached to optics assembly stage 22 ( FIG. 3 ) is positioned between rectangular yoke mount 310 and quarter-waveplate 340 . Fast steering mirror 346 receives an incoming laser beam 348 propagating along beam axis 206 and directs laser beam 348 through quarter-waveplate 340 and scan lens 30 . Quarter-waveplate 340 imparts circular polarization to the incoming linearly polarized laser beam, and fast steering mirror 346 directs the circularly polarized laser beam for incidence on selected locations of the work surface of a target specimen supported on specimen stage 26 . When fast steering mirror 346 is in its neutral position, Z-axis 280 , beam axis 206 , and the propagation path of laser beam 348 are collinear. When fast steering mirror 346 is in operation, the propagation path of laser beam 348 is generally aligned with beam axis 206 .
Flexible steel member 276 is rigid in the Z-axis direction but is compliant in the X-Y plane. These properties of flexible steel member 276 enable it to function as a buffer, isolating the guiding action of air bearing assembly 202 containing scan lens 30 from the guiding action of lens forcer assembly 210 that moves scan lens 30 .
Lens forcer assembly 210 and air bearing assembly 202 have centers of gravity and are positioned along the Z-axis. Voice coil bridge 236 of lens forcer assembly 210 has two depressions 350 , the depths and cross sectional areas of which can be sized to achieve the axial alignment of the two centers of gravity. Such center of gravity alignment eliminates moment arms in control system 28 and thereby helps reduce propensity of low resonant frequency vibrations present in prior art cantilever beam designs.
Several examples of possible types of laser processing systems in which positioning system 10 can be installed include semiconductor wafer or other specimen micromachining, dicing, and fuse processing systems. In a wafer dicing system, laser beam 348 moves along scribe locations on the wafer surface. In a wafer fuse processing system, a pulsed laser beam 348 moves relative to wafer surface locations of fuses to irradiate them such that the laser pulses either partly or completely remove fuse material.
It will be obvious to those having skill in the art that many changes may be made to the details of the above-described embodiments without departing from the underlying principles of the invention. The scope of the present invention should, therefore, be determined only by the following claims.
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A rigid support structure allows for faster and more accurate positioning of axially adjustable optical components in a laser processing system. Vibrational and thermal stability is improved when an optics assembly is housed in a rigid air bearing sleeve that is mounted to a support structure above a specimen stage.
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BACKGROUND OF THE INVENTION
This invention relates to thin-metal-wire conjugated yarn which is excellent in suitability for clothing, for example, feeling, appearance, color effect, etc. and has an electromagnetic interference (referred to as "EMI", hereinafter) shielding function.
Cloths for the purpose of EMI shielding include, for example, cloth obtained by plating the surface of cloth with metals such as nickel, copper, etc.; clothing for EMI shielding obtained by forming a metal plating layer on the surface of cloth which is disclosed, for example, in Japanese Utility Model Registration Unexamined Publication No. 61-64115; cloth made of spun yarn with metal short fiber blended; and cloth obtained by using gold thread or silver thread produced by winding gold leaf or silver leaf round carbon fiber as core thread which has been proposed i Japanese Utility Model Registration Unexamined Publication No. 61-2407.
However, the metal-plated cloth is limited in color to a single color characteristic of the metal used, is poor in feeding and appearance as clothing, is expensive, and is greatly lowered in EMI shielding effect with an increase of the frequency of use or washing.
In the case of the cloth obtained by using spun yarn with metal short fiber blended, the end of metal fiber juts out from the surface, so that unpleasant feeling is caused at the time of wearing. Furthermore, the tinsel such as gold and silver threads obtained by winding metallic leaf is disadvantageous in that it has a rough and hard feeling and is poor in suitability for clothing because the metallic leaf is produced by evaporating a metal on film-like substance, and hence the use of the tinsel is limited.
SUMMARY OF THE INVENTION
This invention is intended to solve these problems and provides yarn which is excellent particularly in suitability for clothing, for example in, feeling, appearance, color effect, durability, etc. and has EMI shielding effect.
This invention provides thin-metal-wire conjugated yarn comprising a core composed of a thin metal wire having a diameter of 50 μ or less and a chemical or synthetic fiber or natural fiber yarn, and another synthetic or chemical fiber or natural fiber yarn as a sheath wound round and covering said core, which is characterized in that the covering percentage is 70% or more based on the surface area of the conjugated yarn.
BRIEF DESCRIPTION OF THE DRAWINGS
The attached drawings are briefly explained below.
FIG. 1 is an exterior view of thin-metal-wire conjugated yarn of this invention obtained by means of a hollow-spindle type twister.
FIG. 2 is an exterior view of thin-metal-wire conjugated yarn of this invention obtained according to the example.
FIG. 3 is a model-like enlarged top plan view of one example of this invention.
The numbers in the drawings show the following materials:
1: thin metal wire in core portion
2: chemical or synthetic fiber or natural fiber yarn in core portion
3 and 3': chemical or synthetic fiber or natural fiber yarn in sheath portion
4: thin-metal-wire conjugated yarn as warp
5: thin-metal-wire conjugated yarn as weft
DESCRIPTION OF THE PREFERRED EMBODIMENT
This invention is explained below in detail with reference to the above drawings.
As the thin metal wire (1) shown in FIG. 1, a thin wire of electrically conductive metal such as stainless steel, copper or the like is used, though good results can be obtained when there is used a thin wire made preferably of copper excellent in flexibility on the surface of which a layer has been baked in order to improve the rust-preventive effect. As a result of experiments, the diameter of the wire should be 50 μ or less, preferably about 20 to about 30 μ. When it exceeds 50 μ, no sufficient suitability for clothing can be attained, for example, the resulting conjugated yarn is poor in flexibility and hence difficult to process, and moreover cloth made of the conjugated yarn is rough and hard and is insufficient in recovery from deformation and draping properties.
On the other hand, a thin metal wire having a diameter of 50 μ or less should be reinforced with chemical or synthetic fiber or natural fiber yarn (2) because it involves, for example, the following problems: its strength is very low; when it is used alone as the core portion, the processability is unstable; and even when it can be made into conjugated yarn, it breaks in a process of processing into cloth.
As the thin metal wire, there is used one which has such an elongation of 15% or less as permits practical use of the wire. Such a thin metal wire is disadvantageous in that it is low in recovery from elongation, and therefore when there is required a step in which the conjugated yarn is subjected to excessive elongation, the thin metal wire in the core portion does not recover from the elongation and tends to jut out from the surface of the conjugated yarn.
Such a trouble can be prevented by using chemical or synthetic fiber or natural fiber yarn having an elongation of 10% or less, preferably 5% or less for forming the conjugated yarn.
The thin metal wire has a boiling water shrinkage percentage of substantially zero, and therefore when the boiling water shrinkage percentage of the chemical or synthetic fiber or natural fiber yarn forming the conjugated yarn is high, the thin metal wire tends to jut out from the surface layer of yarn in the sheath portion owing to heat treatment in a dyeing step or the like and injures the feeling and appearance of cloth made of the conjugated yarn. These defects can be prevented by using chemical or synthetic fiber or natural fiber yarn having a boiling water shrinkage percentage of 5% or less, preferably 3% or less.
Furthermore, the thin metal wire (1) and the chemical or synthetic fiber or natural fiber yarn (2) both constituting the core portion may be in doubled state, though when they are twisted together as shown in FIG. 2, conjugated yarn more stable to the problems described above can be obtained.
The percentage of covering with the chemical or synthetic fiber or natural fiber yarn (3) forming the sheath portion is adjusted to 70% or more, preferably 90% or more based on the surface area of the conjugated yarn, whereby it becomes possible to obtain a usual, sufficient dyeing effect and the conjugated yarn permits, as yarn for clothing, free selection of its color tone and can have a feeling suitable for clothing.
FIG. 3 is a model-like enlarged top plan view of one example of fabric of this invention. In FIG. 3, both the warp (4) and the weft (5) are metal-thin-wire conjugated yarn, and a plain weave fabric produced therefrom is shown.
Cloth having a good EMI shielding function can be obtained by weaving the conjugated yarn in the lengthwise and crosswise directions at a density of 40 or more per inch, preferably 60 or more per inch.
That is to say, in the case of the mesh structure of, for example, fabric, higher the density at which the thin-metal-wire conjugated yarn is woven in the lengthwise and crosswise directions, the more effective EMI shielding function, and therefore the smaller diameter of the thin metal wire in the core portion is more advantageous.
Although the textile weave is not critical, a more desirable result can be obtained when the textile weave is one which has a denser and more uniform mesh structure and more nodes, such as plain weave, twill weave, satin weave, or the like.
The results of rating the effect obtained by employing various textile weaves and densities are shown in the following table.
______________________________________ Attenuation RatingTextile Density 1000 MHZ ofweave Warp Weft (warp × weft) (dB) effect______________________________________Plain A A 80/inch × 80/inch 45 ⊚weave A A 60 × 60 36 ⊚ A A 40 × 40 30 ○ A A 30 × 30 20 Δ B B 80 × 80 30 ○ C A 80 × 80 3 xTwill A A 80 × 80 38 ⊚weaveSatin A A 80 × 80 36 ⊚weave______________________________________ A . . . conjugated yarn of this invention produced according to the example described below. B . . . the conjugated yarn and polyester filament 150D/48F which were arranged in the manner of 1 × 1. C . . . polyester filament 150D/48F.
Next, as to a process for producing the thin-metal-wire conjugated yarn of this invention, the conjugated yarn can be produced by means of a ring twister having an overfeeding mechanism or a hollow-spindle type twister. The number of the yarns used for producing the conjugated yarn is not limited to one but may be two or more depending on purposes.
It is possible to obtain cloth by means of a conventional weaving machine such as fly shuttle loom, rapier loom, or the like by using the conjugated yarn.
EXAMPLE
A thin copper wire having a diameter of 24 μ and a piece of polyester filament yarn 30d/24f were doubled, and using them as core portion and two pieces of polyester filament false-twisted yarn 75d/36f as sheath portion, covering twisting was conducted under the conditions described below to obtain thin-metal-wire conjugated yarn having a covering percentage of about 90% and a sufficient flexibility. Further, the conjugated yarn was made into plain weave having warp and weft densities of 80/inch each, whereby there could be obtained cloth which was good in processability and dyeability, had sufficient feeling and appearance for clothing, and was excellent in EMI shielding function.
Twister: a ring twister
Rotation rate: 7,200 r.p.m.
Number of twist: 400 t/m
Tension of yarn in the core portion: 35 g
Overfeeding percentage of yarn in the sheath portion: 4%
EFFECT OF THE INVENTION
This invention, by virtue of its constitution described above, provides yarn and cloth which have both EMI shielding function and suitability for use in clothing such as desirable color, appearance, feeling, durability, etc., and can be used in various ways in which sufficient fashionability is added to clothes such as working clothes, uniforms, white robes and the like, curtains, wall materials, etc. all for preventing EMI. Thus, this invention has great industrial effects.
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Thin-metal-wire conjugated yarn excellent in suitability for clothing and having EMI shielding which comprises a core composed of a thin metal wire having a diameter of 50μ or less and a chemical or synthetic fiber or natural fiber yarn, and another chemical or synthetic fiber or natural fiber yarn as sheath wound round and coated on said core, characterized in that the coating percentage is 70% or more based on the surface area of the conjugated yarn.
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BACKGROUND OF THE INVENTION
In the 1950's it was discovered that enzootic abortion in ewes (EAE) was carried by infection of the animals with a virus strain of the Psittacosis-Lymphogranuloma group [Young et al, J.A.V.M.A., Vol. 133 (Oct. 1, 1958) p. 374] was classified as Chlamydia sp. [Becerra et al, Zbl. Bakt., I. Abt. Orig. Vol. 214, pp. 250-258 (1970)].
Earlier in the same decade, workers in the field found that the inoculation of ewes at or near breeding time with a vaccine prepared from (1) virus infected yolk sacs or (2) virus infected ovine foetal membranes was effective in reducing the incidence of EAE. The chlamydia elementary bodies were concentrated from infected chicken embroys or foetal membranes, inactivated and used to prepare the vaccine. McEwen et al, Vet. Rec., Vol. 63, p. 197 (3/17/51); McEwen et al. Vet. Rec., Vol. 66, p. 393 (7/10/54); McEwen et al. Vet. Rec., Vol. 67, p. 393 (5/21/55); McEwen et al, Vet. Rec., Vol. 68, p. 686 (10/6/56); McEwen et al, Vet. Rec. Vol. 68, p. 690 (10/6/56); Hulet et al, Am. J. Vet. Res. Vol. 26, p. 1464 (1965); Frank et al, Am. J. Vet. Res., Vol. 29, p. 1441 (1968); Meinershagen et al, Am. J. Vet. Res., Vol. 32, p. 51 (1971).
Serial passage of a virulent microorganism outside the natural host is an accepted method for selecting variants (attenuated strains) with decreased virulence. Wilson, G. S., and Miles, A. Topley and Wilson's Principles of Bacteriology, Virology, and Immunity, Williams & Wilkins, 6th edition 1975 Vol. 1, p. 412-416.
There have also been reports of successful immunizations of ewes against chlamydial abortion with chlamydial organisms attenuated by serial passage in chicken embroys. See Mitscherlich, E., The Control of Virus Abortion of Sheep, Berl-Munch. Tierarztl, Wschr. 78, Heft 5: 81-100 (1965); Nejvestic, A. and Forsek, Z., Active Immunization in the Prophylaxis of Enzootic Abortion in Ewes--I. Vet. Glasnik, 23, 6: 423-427 (1969); Schoop, G., Wachendorfer, G., Kruger-Hansen-Schoop, U., and Berger, J., Studies on a Live Vaccine for the Control of Miyagawanella Abortion in Sheep, Zbl. Vet. Med., Reihe B., 15, Heft 2: 209-223 (1968); Yilmaz, S., and Mitscherlich, E., Experiences in the Control of Ovine Enzootic Abortion with a Live Vaccine made from an Attenuated Strain of Chlamydia ovis, strain "P", Berl. Munch., Tierarztl., Wschr. 86, Heft 19: 361-366 (1973). Other reports, however, indicate that the virulence of chlamydial organisms was not diminished by serial passage in cell culture or in chicken embryos. See Becerra, V. M., Ata, F. A., and Storz, J., Studies on the Response of Ewes to Live Chlamydia Adapted to Chicken Embryos or Tissue Culture, Canad., J. Compar. Med. 40: 46-52 (1976); Becerra, V. M., and Storz, J., Tissue Culture Adaptation and Pathogenic Properties of an Ovine Chlamydial Abortion Strain, Zentbl, Vet. Med 21: 288-299 (1974); and McKercher, D. G., Robinson, E. A., Wade, E. M., Saito, J. K. and Franti, C. E., Vaccination of Cattle against Epizootic Bovine Abortion, Cornell Vet. 59: 211-226 (1969).
The cost of producing a vaccine utilizing infected yolk sac and/or ovine foetal membrane, however, is prohibitive. Moreover, the vaccine produced according to the published methods is difficult to standardize. The yolk sac and foetal membrane techniques are not only expensive but are time-consuming and inefficient. As a result, there is no commercially attractive EAE vaccine available in the United States at the present time. It is believed that immunizations against EAE are presently carried out only in Idaho utilizing locally batch-produced yolk sac or foetal membrane based vaccines. The difficulty of standardization of these vaccines, however, has led to mixed and unpredictable results.
Inasmuch as enzootic abortion in ewes (EAE) is a serious problem in the sheep-breeding industry and responsible for abortion losses in susceptible flocks as high as 30%, there is an urgent need for an economically viable vaccine and method for the active immunization of ewes against EAE.
It is an object of the present invention to provide a vaccine for the active immunization of ewes against enzootic abortion.
It is a further object of the present invention to provide a method for immunizing ewes against EAE.
It is a further object of the present invention to provide a relatively simple, efficient and economically attractive method for the preparation of a vaccine against EAE.
It is a still further object of the present invention to provide an easily standardized intermediate composition especially adapted for preparing a vaccine against EAE.
SUMMARY OF THE INVENTION
The invention is predicated on the discovery that an economically feasible and commercially attractive vaccine for the active immunization of ewes against enzootic abortion (EAE) can be prepared from Chlamydia sp. elementary bodies propagated on and isolated from cell culture. It has been found that cell culture grown Chlamydia sp. elementary bodies are more economically and efficiently produced than chicken embryo and foetal membrane derived strains. Moreover, the cell culture produced composition is more readily standardized than those produced heretofore.
DETAILED DESCRIPTION OF THE INVENTION
The invention relates to an aqueous suspension of inactivated chlamydial elementary bodies propagated on and isolated from a cell culture from which a vaccine against EAE can be formulated by dilution with a parenterally administrable carrier.
Following is a non-limiting example of a method for the preparation of the aqueous suspension:
A single strain of Chlamydia sp. isolated from an infected ovine fetus is used to prepare the suspension. The organism is propagated on cultures of mouse fibroblast L-cells (NCTC 929) either in standing monolayers, roller bottles, or suspended microcarrier cultures using 10% Eagle's Minimum Essentials Medium supplemented with 5% bovine fetal serum. A confluent monolayer (or its equivalent in a roller bottle or suspended culture) is inoculated with 1 ml of chlamydia suspension containing 1×10 8 embryo lethal doses (ELD 50 )/0.5 ml. The cultures are incubated at 37° C. in a CO 2 incubator.
Smears are prepared daily from the infected L-cells and stained by the Gimenez method. (Clark et al, Staining Procedures Used by the Biological Stain Commission, 3rd Ed. Williams & Wilkins Co., Balt. Md. 1973, p. 291). When an estimated 80-90% of the L-cells are infected, the tissue culture medium from the infected L-cells and the infected L-cells which have been detached from the growth surface with a versene-trypsin solution are combined to use as inoculum for fresh L-cell cultures. One standing monolayer (or its equivalent) is used as "seed" for 5 fresh monolayers (or equivalent) of equal size and volume. The progress of the chlamydia infection is again monitored as above.
The culture fluid and infected L-cells from standing culture flasks (or equivalents) are harvested when 80-90% of the cells are infected. The infected fluids and detached cells are pooled and centrifuged at 16,300×g for 30 minutes. The supernatent fluid is discarded and the pellet resuspended in Bovarnicks' sucrose-phosphate buffer (Bovarnicks et al, J. Bact. 1950, Vol. 59, pp. 509-22) to give a final volume equal to 1/100 of the amount harvested. A 2 ml portion of this suspension is removed for infectivity titration in 7-day-old chicken embryo. Sufficient formalin is added to the remainder to give a final concentration of 0.4% formalin. The formalin-treated suspension is stored at 37° C. for 1 week and then tested for sterility.
The suspension is again separated by centrifugation, the supernatant fluid discarded, and the pellet resuspended in phosphate buffered physiological saline containing 0.2% formalin. The final volume is adjusted (using the results of the infectivity titration) to give a concentration of chlamydial elementary bodies equivalent to 10 8 .3 ELD 50 /0.25 ml.
It will be understood that the chlamydial strain may be obtained from any convenient source and propagated on any suitable cell culture, e.g., chicken fibroblasts, yolk sac, McCoy (human synovium), lamb fetal kidney, lamb fetal lung, lamb fetal spleen, FAM (human amnion), HEP-2 (human laryngeal tumor, lamb testicle, He La, Sirc (rabbit cornea), green lizard liver, etc., cells.
It will also be apparent that any suitable killing agent can be utilized for the purpose of inactivating the chlamydia organisms, e.g., formalin, ultraviolet irradiation, thermal (56° C. for 5 or more minutes), phenol, repeated freezing and thawing, beta-propiolactone, acetone, ether, acetone-ether mixtures, etc.
The propagation may be continued until there is present in the final suspension an amount of chlamydial elementary bodies in the range of from 10 6 to 10 9 ELD 50 /0.25 ml.
A vaccine in unit dosage form suitable for immunization against EAE may be formulated by diluting the above aqueous suspension with an equal volume of a physiologically acceptable and parenterally administrable carrier. For example, an equal volume of oil adjuvant (4 parts light mineral oil and 1 part lanolin) may be added to the suspension prepared above in a mechanical blender operated at low speed. When the addition of the adjuvant is complete, the resulting mixture is homogenized, bottled, and stored for use.
The vaccine is administered by subcutaneous injection of a single 1 ml dose at or near breeding time, it being understood that a suitable dose is one containing from about 2×10 6 to about 2×10 9 ELD 50 /ml.
The resulting vaccine is much less expensive to prepare, is more readily standardized and yields a more enhanced degree of immunization against EAE than the previously proposed vaccines derived from chicken embryos (yolk sac) and ovine foetal membranes.
In order to demonstrate the value and effectiveness of the vaccine of the present invention, an attempt was made to attenuate a chlamydial strain by serial passage in chicken embryos and prepare a vaccine therefrom. The procedure employed was as follows:
A single strain of Chlamydia psittaci (Ark 2) was used in the experiment. The test organism was isolated from an aborted lamb and was cultured by serial passages in seven-day-old CE. The chlamydia for inoculation of ewes in Lot 2 were passed in CE 7 times at 37 C and 10 times at 40 C. For Lots 1 and 3, the inoculums were prepared from chlamydia cultured in CE at 37 C for the number of passages indicated (Table 1). Lot 3 served as a control in which the ewes were inoculated with a virulent strain of chlamydia. Lot 4 was not inoculated and served as a normal control. Preparation of inoculums for sheep and their CE infectivity determinations were performed according to the methods described in Reed, L. J. and Muench, H., A Simple Method of Estimating Fifty Percent Endpoints, Am. J. Hyg. 26: 493-497 (1938); Storz, J., Chlamydia and Chlamydia-Induced Diseases, Chas. C. Thomas, 1971, p. 154; and Waldhalm, D. G., Frank, F. W., Meinershagen, W. A., Philip, R. N., and Thomas, L. A., Lamb Performance of Ewes Inoculated with Chlamydia sp. Before and After Breeding, Am. J. Vet. Rest., 32: 809-811 (1971). The inoculums given ewes in Lots 1 and 2 contained 10 8 .48 and 10 3 .46 50% embryo lethal endpoint units (ELD 50 ), respectively. Primiparous ewes were inoculated intramuscularly with 1 ml of chlamydia suspension at approximately the 100 th day of gestation.
Liver and stomach contents from aborted fetuses and lambs which died in less than 24 hours after birth were cultured for Campylobacter (Vibrio) fetus and other pathogenic bacteria. Stained [Stamp, J. T., McEwen, A. D., Watt, J. A. A., and Nisbet, D. L., Enzootic Abortion in Ewes, I, Transmission of the Disease, Vet. Rec. 62: 251 (1950)] impression smears from placentas, vaginal discharges, and the skin surfaces of aborted fetuses were examined for the presence of chlamydia.
The results were summarized (Table I). No pathogenic bacteria were isolated from aborted fetuses or from weak lambs. The ewes in Lot 3 had the highest percentage of abortion (67%), but there was no statistically significant difference between any two of the lots (P>0.5).
The results of the present study indicate that serial passage of Chlamydia psittaci strain (Ark 2) in CE including passages at high incubation temperature did not affect the pathogenicity of the organism for pregnant ewes. The results are in agreement with reports of other attempts to modify the virulence of chlamydia, and do not substantiate the reports of successful immunization of ewes with live chlamydia that had been subjected to serial passage in CE.
TABLE I__________________________________________________________________________Pathogenicity of Chlamydia psittaci (strain Ark 2) in Pregnant Ewes. Ewes Ewes with Number Inoculum with Weak Lambs.sup.+ of Ewes withLot No. of Inoculum Infectivity Live or Placentas InfectedNo. Ewes Treatment (ELD.sub.50) Lambs Abortion Examined Placentas__________________________________________________________________________1 12 110 CE passages* 10.sup.8.48 5 7 6 62 13 7 CE passages 10.sup.8.46 9 4 11 8 at 37 C. plus 10 CE passages at 40 C.3 12 8 CE passages ND** 4 8 11 104 14 None (Normal -- 14 0 2 0 control)__________________________________________________________________________ .sup.+ Born alive but died within 24 hours. *Embryos were incubated at 37 C. except as noted. **Not determined.
A test was conducted wherein cell culture propagated vaccine was compared with chicken embryo propagated vaccine. The two vaccines contained equal amounts of inactivated chlamydia organisms and were similar in all respects except for the mode of propagation.
Eighty-three yearling ewes were selected from a commercial herd on the basis of low antibody levels against chlamydia antigen. The antibody levels were determined by enzyme-linked immunosorbent assay (ELISA). The ewes were ear tagged for identification and kept in a single group until the time of challenge inoculation.
Two days before breeding was begun, 50 randomly selected ewes were vaccinated: 25 received cell culture origin vaccine and 25 received chicken embryo origin vaccine. Vaccines were administered in 1 ml doses subcutaneously. The remaining ewes were not vaccinated.
Blood samples for serology were collected at the time of vaccination and on post vaccination days 14, 28, 100, 107 and 114. Antibody concentrations were determined by ELISA.
On post vaccination day 100 the ewes were divided into separate groups as shown in Table 2. Each ewe in the vaccinated groups and 25 nonvaccinated ewes were inoculated orally with 5 ml of a suspension of live, virulent Chlamydia psittaci containing 10 8 .3 ELD 50 /05 ml in sucrose phosphate buffer.
TABLE 2______________________________________Comparison of vaccine prepared from Chlamydiagrown either in chicken embryos of L-cell monolayers No. ofGroup Ewes Treatment Challenge Inoculum______________________________________1 25 cell culture origin virulent Chlamydia psittaci vaccine2 25 chicken embryo virulent Chlamydia psittaci origin vaccine3 25 none virulent Chlamydia psittaci (infected control)4 25 none none (normal control)______________________________________
Aborted fetuses and associated membranes were examined microscopically and by bacteriologic culture to ascertain the cause of abortion. In all cases Chlamydia psittaci was determined to be the cause.
The relative efficacies of the two vaccines can be judged from the lambing performances of the various groups (Table 3) and from the antibody responses (in terms of absorbencies) elicited by the two preparations (Table 4).
TABLE 3______________________________________Lambing performance No. of No. of Infected Preg- No. of Ewes Placentas/ nant with Abortions No. Ex-Group Treatment Ewes or Weak Lambs* amined______________________________________1 cell culture 22 1.sup.a 0/12.sup.a vaccine2 chick embryo 25 2.sup.a 0/13.sup.a vaccine3 nonvaccinated 23 8.sup.b 6/12.sup.b challenged4 normal control 8 0.sup.a 0/7.sup.a______________________________________ *Weak Lamb = died in 48 hours or less .sup.a,b Values between treatments with different superscripts differ (P 0.03) significantly.
TABLE 4__________________________________________________________________________Mean ELISA Absorbencies (X-- ± S.D.) Days Post Vaccination:Group Treatment 0 14 28 100* 107 114__________________________________________________________________________1 cell culture vaccine 0.15 ± .11 0.28 ± .15 0.50 ± .24 0.48 ± .17 0.44 ± .21 0.55 ± .182 chick embryo vaccine 0.16 ± .14 0.31 ± .24 0.43 ± .19 0.34 ± .17 0.33 ± .14 0.40 ± .133 nonvaccinated challenged 0.14 ± .09 0.16 ± .12 0.16 ± .12 0.14 ± .10 0.15 ± .09 0.44 ± .194 normal control 0.17 ± .14 0.17 ± .10 0.20 ± .11 0.14 ± .09 0.14 ± .10 0.13 ± .10__________________________________________________________________________ *Day of challenge
Both vaccines gave significant protection against abortion and weak lambs and both elicited an antibody response measurably greater than the controls. These results show further, in terms both of protection against lamb mortality and of measured antibody response, that the cell culture grown vaccine elicited a better response than the chicken embryo propagated product. This is especially evident in the greater average absorbencies shown in Group 1 from the 28th post vaccination day until the end of the study at day 114.
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A vaccine composition and method for the immunization of ewes against EAE (enzootic abortion in ewes) based upon inactivated Chlamydia sp. propagated in cell culture. The invention also relates to a method for the preparation of said vaccine and an intermediate therefor.
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BACKGROUND
In my previous U.S. Pat. No. 4,730,797 entitled "Inflatable Core Orbital Construction Method and Space Station" filed Aug. 12, 1985, I disclosed an automated method and operating system for constructing large continuous-walled structures in orbit by robotics. In that method, a lightweight, non-elastic, inflatable surface with thin flexible walls is transported to orbit and inflated like a balloon to form a semi-rigid surface. The surface is then used as a guide for constructing the wall of the structure by wrapping the inflated surface with long sheets of flexible high-strength material until the desired wall thickness is obtained. The wrapping process is accomplished automatically by a wrapping machine.
Unfortunately, that method of orbital construction had a number of operational problems. For example, the diameter could not be very large because the inflation pressure would generate stress that could easily exceed the stress limitations of the inflated surface. Since the pressure had to be relatively low, it did not serve very well as a firm guide surface for the wrapping material and could be deformed during the wrapping process. The inflated surface was also subject to accidental deflation before it could be completely wrapped and made rigid. It was also limited to finite dimensions. But the most serious defect inherent in that method of orbital construction was the fact that the wrapping machine had to move around the inflated surface along a precise predetermined path while it wrapped the material around it. This was a technically difficult and tedious process since the machine had to move over the surface many times to build up the wall thickness by wrapping it with many layers of wrapping material. Consequently, the machine required considerable time to construct the structure and it required considerable monitoring to make sure it was moving along the required path.
Although the present system is also based on the use of wrapping material for wall building, it represents an entirely new system and operating method because it does not require any preinflated guide surface and does not require the machine to travel anywhere during the construction process.
BRIEF SUMMARY OF THE INVENTION
Thus, in the practice of this invention according to a presently preferred embodiment, there is provided a high-speed economical method and operating system for automatically constructing large tubular structures in orbit with essentially unlimited dimensions. The system comprises a relatively short tubular conveyor with an inner and outer endless flexible thin conveying medium moving in a longitudinal direction around a smooth cylindrical guide tube, and a plurality of wrapping wheels containing long thin sheets of high-strength wrapping material moving in transverse directions around the outside of the conveyor.
The tubular conveyor comprises a fixed rigid smooth-surfaced cylindrical guide tube with any desired radius. The endless flexible conveying medium moves around the inner guide tube in sliding contacting motion. Rollers are mounted at each end of the guide tube to enable the conveying medium to move smoothly around each end of the guide tube with very little friction. Since the inner guide tube is completely enclosed and sealed inside the flexible conveying medium moving around it, it can be permanently lubricated such that the sliding friction is almost zero.
Since the thin-walled moving conveying medium moves in sliding contact with the inner guide tube, its outer surface has a cylindrical shape identical to the shape of the inner guide tube. Thus, the surface is essentially equal to the surface of the inner guide tube except that it is moving in the longitudinal direction parallel to the central longitudinal axis of the guide tube. That portion of the medium adjacent to the outer surface of the guide tube moves in one direction and that portion adjacent to the inner surface of the guide tube moves in the opposite direction.
By moving the conveyor and simultaneously moving the wrapping wheels around the conveyor, sheets of wrapping material are wrapped firmly onto the moving outer conveying surface of the tubular conveyor thereby forming a rigid continuous-walled multi-layer tubular structure with an inside diameter equal to the outside diameter of the conveyor. The wrapping material is mounted in cartridges that can be easily replaced with full cartridges when the wrapping material is exhausted. Thus, the resulting tubular structure can have any desired length. The layers of wrapping material are bonded to each other as they are laid by liquid resin thus creating a super-strong laminated wall with any desired thickness. The wall thickness is determined by the ratio of rotational speed of the wrapping wheels to the longitudinal speed of the tubular conveyor. A large ratio will generate a thick-walled structure with many layers of wrapping material, and a low ratio will generate a thin-walled structure with relatively few layers.
The wrapping process is accomplished automatically by electric motors. Straight cylindrical structures are obtained by using a straight guide tube, and curved toroidal structures are obtained by using a slightly curving guide tube.
Since the sheets of wrapping material are rolled into spools with very high packing density, it is possible to construct structures with very large dimensions with relatively few trips into orbit to deliver the wrapping material. For example, straight continuous cylindrical beams a few centimeters in diameter but several kilometers long will be easy to construct, as well as the hull of huge torodial space stations with any desired diameter.
DRAWINGS
These and other advantages and features of the invention will be apparent from the disclosure, which includes the specification with the foregoing and ongoing description, the claims, and the accompanying drawings wherein:
FIG. 1 is a schematic longitudinal cross-section illustrating the basic operating principles of a tubular conveyor;
FIG. 2 is a schematic transverse cross-section of FIG. 1;
FIG. 3 is a schematic longitudinal cross-section illustrating the design and construction of the automatic construction machine;
FIG. 4 is a schematic longitudinal cross-section of a pair of wrapping machines;
FIG. 5 is a schematic transverse cross-section of FIG. 4;
FIG. 6 illustrates the invention in the process of manufacturing a long cylindrical structure; and
FIG. 7 illustrates the invention in the process of manufacturing a large toroidal hull for a space station.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In comparison with the previously mentioned automatic orbital construction machine (U.S. Pat. No. 4,730,797), the major design innovation of the present machine is the utilization of a tubular conveyor as a firm wrapping surface instead of an inflatable surface. Since this substitution results in a vastly improved machine and operating method, it is important to understand the unique operating principles and features of tubular conveyors.
The tubular conveyor was invented in 1984 (U.S. Pat. No. 4,601,389) and is essentially a rigid tube or pipe (straight or curved) with flexible moving walls. It provides a means for transporting non-fluid bulk material through an enclosed duct in any direction. FIGS. 1 and 2 are schematic longitudinal and transverse cross-sections, respectively, of a tubular conveyor illustrating the basic design and operating principles.
Referring to FIGS. 1 and 2, the basic design of a tubular conveyor comprises a fixed cylindrical guide tube 10 with smooth inner 12 and outer 14 surfaces. A plurality of rollers 16 are mounted around each end of the guide tube 10. The guide tube 10 is completely enclosed within an endless thin-walled flexible conveying medium 18 that moves longitudinally in sliding contact continuously around the guide tube 10 over the rollers 16. The conveying medium 18 is constructed with elastic material to enable it to move around the guide tube 10 over the rollers 16 hugging its walls without tearing. The moving duct-like conveying surface 20 is represented by the inner surface 22 of the conveying medium 18, and the carrying run 24 is represented by the outer surface 26 moving in the opposite direction. Unlike ordinary belt conveyors, the material moving through a tubular conveyor is completely enclosed by the conveying surface which forms the duct.
The moving surface 18 follows the rigid inner guide tube 10 by a plurality of relatively small sliders 28 that are attached to and protrude a small distance from the inside portion of the moving surface 18. These sliders 28 ride snugly inside a plurality of relatively narrow parallel guide slots 30 that extend longitudinally around both sides of the inner guide tube 10. The sliders moving in the guide slots also constrain the moving surface 18 to moving in a strictly longitudinal direction around the inner guide tube 10.
Since the inside region 32 of the moving surface 18 is separated from the outside environment, the inside components can be hermetically sealed and permanently lubricated with lubricating fluid that never needs to be replaced. Thus, the sliding friction between the guide tube 10 and the inside walls of the moving surface 18 will always remain very low. Although tubular conveyors are used for transporting bulk material from one point to another on the inside duct-like conveying surface 22, it is the moving outside cylindrical surface 24 (the carrying run) that will be utilized in the present invention. FIG. 3 is a schematic longitudinal cross-section of the automatic construction machine 34. Basically, the machine 34 comprises three subsystems: (1) a relatively short cylindrical tubular conveyor 36 with an endless flexible conveying surface 38 moving longitudinally around a fixed double-walled cylindrical guide tube 40; (2) a plurality of wrapping machines 42 mounted in pairs on a stationary outer support structure 44 that rotate transversely around the tubular conveyor 36 wrapping long thin flexible sheets of high-strength wrapping material 46 onto the moving outer surface 48 of the tubular conveyor 36; and (3) an inner central support structure 50 extending along the inner duct 52 of the tubular conveyor 36 attached to the outer support structure 44 that holds the moving tubular conveyor 36 in a fixed position while the moving surface 38 moves longitudinally around the inner guide tube 40.
The tubular conveyor 36 is held in a fixed position between the outer support structure 44 and inner support structure 50 by a plurality of wheels 54 mounted on each end of the central support structure 50 that hold each end of the tubular conveyor 36 by rolling over the moving surface 38 and exerting an inward force. A plurality of inner rollers 56, mounted at each end of the central guide tube 40, force the moving surface 38 outward against the outward supporting wheels 54 that are pushing inward. The path 58 of the flexible moving surface 38 between the wheels 54 and rollers 56 is concave around the larger guide wheels 54, thereby enabling the guide wheels 54 to hold the tubular conveyor 36 in a fixed position by pushing inward from both ends of the conveyor 36 while the flexible surface 38 continuously moves around the inner guide tube 40. (The concave engagement between the outside guide wheels 54 and the inside rollers 56 prevent the conveyor from moving up and down or laterally between the inner support structure 50 and outer support structure 44.)
The inner central support structure 50 is connected to the outer support structure 44 by a plurality of connecting beams 60 mounted on one side of the tubular conveyor. Since the machine 34 continuously manufactures the tubular structure 62 that comes out of one end 64 of the machine 34 (the end of the machine), the connection between the inner structure 50 and the outer structure 44 via the connecting beams 60 can only be accomplished from one end 66 of the machine 34 (the beginning of the machine). Thus, a guide tube (10) and conveying medium (18) form a rigid mandrel on which the wrapping machine (42) wraps material (46) to form a rigid sleeve or tube (62).
The endless moving surface 38 of the tubular conveyor 36 is moved longitudinally around the guide tube 40 by a plurality of electrically driven traction wheels 68 mounted on the outer support structure 44. These wheels 68 are driven by electric motors 70 energized by a large bank of electric batteries 72 mounted on the inner support structure 50 via electric cables 74. The motors 70 are variable speed motors controlled by a central computer 76 that enables the conveyor 36 to move at a predetermined speed. Since the wheels 68 are mounted 360° completely around the conveyor 36, they are designed to exert a significant inward force on the moving outer conveying surface 48 thereby making possible considerable tractive force.
FIGS. 4 and 5 are schematic longitudinal and transverse cross-sections of a pair of wrapping machines 78, each comprising four individual wrapping wheels 80. The wrapping machines are mounted on the outer supporting structure 44 and rotate around the outer moving surface 48 of the tubular conveyor 36 in opposite directions so that the net torque exerted on the moving surface 48 is zero. The machine shown in FIG. 3 has three pairs of wrapping machines 78 containing a total of 24 wrapping wheels.
Referring to FIGS. 4 and 5, the wrapping wheels 80 are mounted on each wrapping machine 78 between two parallel, spaced-apart rings 82. A plurality of relatively small longitudinal support beams 84 connect the rings 82 together and maintain them in a spaced-apart configuration.
The wrapping machines 78 are rotated around the conveyor surface 48 by a system of rotating drive shafts 86 that engage sprockets 88 mounted on circular flanges 90 attached to adjacent rings 82. The drive shafts 86 are rotated by a plurality of variable-speed motors 92 energized by the bank of batteries 72 mounted on the inner support structure 50 via electric cables 94. The speed of rotation of the wrapping machines 78 is controlled by the central control computer 76.
In addition to the large bank of batteries 72, the central support structure 50 also contains a plurality of reaction wheel gyros (RWG's) 96 for maintaining the machine with a certain attitude while it is manufacturing the tubular structure 62. Various accelerometers 98, back-up computers 100, and radio transmitter-receiving control systems 102 are also mounted on the central structure 50.
Each wrapping machine 78 (FIGS. 4,5) is equipped with four receptacles 104 mounted around the circumferential periphery at 90° intervals between the two supporting rings 82. A spool 106 containing a thin continuous sheet of high-strength wrapping material 108 having a certain width (that could range from a centimeter for tubular beams to over a meter for toroidal space stations) is mounted in the form of a plug-in cartridge 110 and is loaded into each receptacle 104. The spool 106, cartridge 110 and receptacle 104, comprise important components of the wrapping wheel 80. Four other replaceable cartridges 112, containing a high-strength bonding agent 114 (such as liquid resin) is loaded into four automatic bonding dispensing systems 116, located adjacent each spool cartridge 110. The bonding fluid is automatically applied as a thin film on the upper side of each sheet of wrapping material when the wrapping machine 78 rotates around the outer moving surface 48. Thus, as each wrapping machine 78 rotates around the outer moving conveying surface 48, four continuous sheets of high-strength wrapping material 108 are automatically wrapped around, and bonded to each other. No bonding material is applied to the moving surface 48. The wrapping material is simply wrapped around the surface 48 in the form of a tight, multi-layer sleeve that is continuously constructed by the wrapping wheels and continuously moved longitudinally away from the machine by the moving conveying surface 48. The tension in each sheet 108 is adjusted by automatic computer controlled tension adjusting systems 120 such that the net torque generated on the conveyor surface 48 by each pair of machines 78 is zero. (Since the wrapping machines in each pair rotate in opposite directions, the torque generated on the surface by tension in the wrapping material cancel each other.)
For the embodiment shown in FIG. 3, the rotating wrapping machines will automatically construct a super-strong laminated cylindrical wall with 24 separate spools of wrapping material unrolling on the moving surface 48 simultaneously. The final wall thickness of the structure 62 coming out of the machine will depend upon the thickness of each sheet and the ratio of the rotational speed of the wrapping machines to the translational speed of the tubular conveyor. For example, if a thick-walled structure is desired, the machine will be operated with a high rotational speed relative to the conveyor speed so that the wall will be many layers thick. If a thin wall structure is desired, some of the wrapping machines can be turned off, and the rotational speed of the operating units will be slow relative to the conveyor speed.
The inside diameter of the structure will be equal to the outer diameter of the conveying surface 48 (which could range from a few centimeters for tubular beams to several meters for space stations). If the guide tube 40 is straight, the resulting structure will be straight and could have any length desired. As soon as the cartridges of wrapping material and bonding material are exhausted, they are simply removed by astronauts and replaced by full cartridges transported to orbit by launch vehicles. The process of replacing the various cartridges with full cartridges will be relatively easy because they are designed to slip out of, and into the corresponding receptacles without requiring any careful prealignment or other tedious procedures.
An important operating design feature of the present orbital construction machine that distinguishes it from the above mentioned prior design (U.S. Pat. No. 4,730,797) is the fact that the moving outer surface 48 being wrapped cannot be depressed inward (deformed from a perfect cylindrical cross-section) by the driving wheels 68 or by tension in the wrapping material 108 because the surface 48 is backed up by the very strong cylindrical guide tube 40 of the tubular conveyor 36. Moreover, this machine is much easier to operate because it does not have to move over any predetermined path around a gas filled surface. Aside from :its orbital velocity, the machine remains stationary. The desired wall thickness of the structure 62 is simply fed into the central control computer 76 as input data which computes the required speed ratio to generate the desired wall thickness. The computer automatically controls the speed of the motors 70, 92 to automatically produce the required ratio so that the structure 62 coming out of the machine has the precise thickness desired. The attitude control moment gyros keep the machine fixed in space relative to a near-by manned support vehicle.
FIG. 6 illustrates the orbital construction machine 34 in the process of manufacturing a straight continuous cylindrical structure 122 with any desired length. FIG. 7 illustrates the construction machine 34 in the process of manufacturing a very large toroidal structure 124 for a space station. As described above, in the case of toroidal structures, the guide tube 40 of the tubular conveyor 36 has a radius of curvature equal to the major radius of the toroidal structure.
Referring to FIG. 3, the connecting beams 60 between the inner structure 50 and the outer structure 44 of the construction machine 34 are designed to be detachable. Consequently, when a torodial structure 124 is almost finished as is shown in FIG. 7, the inner structure 50 can be disconnected, and the beginning of the toroidal structure 126 can be fed back into the wrapping machines and thereby joined to the end of the structure making the completed structure an endless super-strong torus. A system of back-up batteries, control computers, attitude control moment gyros, etc., are provided on the outer structure 44 to operate the wrapping wheels without the inner structure 50.
When the machine 34 is used to construct long cylindrical beams, all of the wrapping wheels could be loaded with the same material. For example, suppose that a 1,000 m long cylindrical beam with an inside diameter of 1.0 m and a wall thickness of 0.5 cm made of aluminum alloy with a density of 2.7 gm/cm 3 is required. The total mass of the beam would be 42,412 kg. If the machine illustrated in FIG. 3 is used for the construction, each of the 24 wrapping wheels would be loaded with a 1,767 kg continuous aluminum sheet. If the conveyor speed is set for 1.0 m/sec, the machine would construct the beam in 1,000 sec or 16.67 minutes.
When the machine is used to construct toroidal space stations (see U.S. Pat. No. 4,730,797) the wrapping wheels could contain sheets of various material. For example, some wheels could be loaded with sheets of KEVLAR, others loaded with sheets of aluminum alloy, others with sheets of boron (for radiation shielding) and others with sheets of carbon composite material. The resulting structure will be composed of all these sheets bonded together to form a super-strong laminated-wall structure that could have any desired thickness and size. After the machine is assembled and loaded with the wrapping material, it could proceed to automatically construct the hull of the structure without any human assistance and, it will construct the structure rapidly with a degree of precision far beyond anything that could be achieved by astronauts assembling the structure one section at a time by conventional construction methods in an orbiting construction center.
Many different embodiments of the invention are possible. For example, the moving surface 38 could be composed of a plurality of endless belts instead of a single elongated toroidal surface, The guide tube 40 could have an elliptical cross-section instead of a circular cross-section. It could also have a square or triangular cross-section. Since the transverse cross-section of the resulting structure is equal to the external transverse cross-section of the guide tube 40, the machine will be capable of making tubular structures with circular, square, triangular, and many other cross-sections. Equilateral triangular cross-sections would be very useful in the construction of long beams.
In another embodiment, the outer structure 44 is not physically connected to the inner structure 50 that supports the conveyor, It could simply operate around the conveyor keeping the conveyor centered inside (via the traction wheels 68) by a plurality of sensors.
Still other embodiments of the invention could replace the inner cylindrical guide tube 40 with a plurality of rollers.
In another embodiment, the wrapping wheels 80 do not have to rotate around the conveyor 36. The conveyor can itself be rotated along its longitudinal axis while the conveying surface 38 is moving simultaneously. In this design, the wrapping wheels can remain in fixed positions relative to the supporting structure 44, while the flexible wrapping material unwinds on the rotating conveyor surface 48 thereby forming a continuous tubular structure.
The invention could also be used to construct structures on the surface of celestial bodies and is not limited to orbital construction. It could also be used for manufacturing relatively small ultra high-pressure tubular conduits or high-pressure cylindrical vessels for industry. Another application would be in the manufacture of cylindrical pipes or conduits for general construction or large civil engineering projects. It could also be used for constructing large cylindrical sections of aircraft fuselage or other vehicles. Still other applications would be in the construction of toroidal or cylindrical shaped homes or buildings on earth or on other celestial bodies.
As various other changes and modifications can be made in the above automatic construction method and operating system without departing from the spirit or scope of the invention, it is intended that all subject matter contained in the above description or shown in the accompanying drawings should be interpreted as illustrative and not in a limiting sense.
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A high-speed automated method and operating system is disclosed for constructing continuous-walled tubular structures in space having unlimited dimensions. The system comprises a relatively short tubular conveyor with a flexible endless conveying surface sliding in a longitudinal direction around a smooth cylindrical inner guide tube, and a plurality of wrapping wheels containing wrapping material moving in transverse directions. By moving the conveyor and simultaneously moving the wrapping wheels around the conveyor, sheets of material are wrapped around the outer conveying surface made firm by the inner guide tube to continuously manufacture a rigid multi-layered laminated walled cylindrical structure with an inside diameter equal to the outside diameter of the tubular conveyor. By varying the conveyor speed-to-wrapping wheel speed ratio, any wall thickness is obtained. The wrapping material is rolled into spools, mounted inside cartridges, and loaded into the wrapping wheels for easy insertion and replacement. Thus, the manufacturing process can be continued indefinitely to obtain a tubular structure having any dimensions desired. Since the sheets of wrapping material are transported to orbit in rolls with very high packing density, the machine can construct huge structures in orbit with relatively few trips.
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CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application, pursuant to 35 U.S.C. §119, claims priority to U.S. Provisional Application No. 61/675,074, filed on Jul. 24, 2012, which is incorporated herein by reference in its entirety.
BACKGROUND
[0002] In oil and gas exploration and development operations, it is often desirable to remove casing which has previously been set in the wellbore. Casing removal requires that the casing string first be severed, and the free end then pulled to the surface, to remove the severed portion.
[0003] Conventional apparatus and techniques for extraction of well casing typically involve the use of multiple trips to move cutting and extracting equipment downhole. Thus, in removal operations a cutting device is first lowered into the wellbore to cut the casing at a desired depth after which time the cutting device is returned to the surface. A spearing device is then lowered inside the well and engaged to the free end of the casing. Once the free end of the casing is engaged, an attempt is then made to recover the casing by pulling, or, in the case where jars are used, by a combination of pulling and jarring. If these attempts to remove the casing are unsuccessful, the spear assembly is removed from the wellbore and the cutting device reattached to the tool string to sever the casing at a point above the original cut. The pulling/jarring process is then repeated until the casing is recovered.
[0004] Such prior art apparatuses and techniques for retrieving well casing are time consuming and costly. This time and expense is a result of the utilization of separate cutting and extraction tools, which are typically run downhole independently. Even when casing is retrieved without the need to complete a second cut of the casing, at least two trips are necessary for a complete cutting and retrieval operation. When a significant length of casing is extracted, considerable rig time must be used to move the tools downhole to the site of the cut. Time and expense are therefore increased when multiple cuts are necessary to retrieve the casing.
[0005] In certain operations, casing cutting may be required when performing slot recovery operations. During slot recovery, the object is to construct a new well with new barriers from a previously used slot while shutting off all communication with an old reservoir. Cutting and pulling casing may be restricted due to cement behind production casing or barite settling from drilling fluid in the production casing annulus. Such slot recovery operations may thus require the cutting and removal of multiple sections of casing from a wellbore. Because slot recovery operations often involve cutting a casing segment in a first trip and pulling the cut casing in a second trip, such operations are often time consuming and expensive.
SUMMARY OF THE CLAIMED EMBODIMENTS
[0006] In one aspect, embodiments disclosed herein relate to a spearing device for use in removing casing from a wellbore. The spearing device may include: a top sub; a bottom sub; a mandrel coupled to the top sub and bottom sub and having an outer surface, at least a portion of which is corrugated. The spearing device also includes: a grapple including one or more grapple members having a correspondingly corrugated inner surface and at least a portion of an outer surface of the grapple members including wickers for engaging an interior surface of the casing, wherein the grapple is configured to (i) axially and rotationally move along the corrugated outer surface of the mandrel and (ii) expand and collapse the grapple members responsive to axial movement relative to the mandrel; a piston slidably disposed within the mandrel and operatively connected to the grapple; and a spring operative with the piston and biasing the grapple toward a collapsed position. Responsive to an increase in hydraulic pressure, the piston compresses the spring and axially moves the grapple, expanding the grapple members. Responsive to a subsequent decrease in hydraulic pressure, the spring decompresses and axially moves the grapple, collapsing the grapple members.
[0007] In another aspect, embodiments disclosed herein relate to a downhole tool for cutting and removing casing from a wellbore. The tool may include: a cutting device disposed on a tool string and configured to make at least one casing cut; and, a spearing device disposed on the tool string and configured to engage and remove casing cut by the at least one cutting device from the wellbore. The spearing device may include: a top sub; a bottom sub; a mandrel coupled to the top sub and bottom sub and having an outer surface, at least a portion of which is corrugated; a grapple including one or more grapple members having a correspondingly corrugated inner surface and at least a portion of an outer surface of the grapple members including wickers for engaging an interior surface of the casing, wherein the grapple is configured to (i) axially and rotationally move along the corrugated outer surface of the mandrel and (ii) expand and collapse the grapple members responsive to axial movement relative to the mandrel; a piston slidably disposed within the mandrel and operatively coupled to the grapple; and a spring operative with the piston and biasing the grapple toward a collapsed position. Responsive to an increase in hydraulic pressure, the piston compresses the spring and axially moves the grapple, expanding the grapple members. Responsive to a subsequent decrease in hydraulic pressure, the spring decompresses and axially moves the grapple, collapsing the grapple members.
[0008] In another aspect, embodiments disclosed herein relate to a method of removing casing from a wellbore. The method may include: disposing a downhole tool assembly in a wellbore, the downhole tool assembly including a first cutting device and a first spearing device. The spearing device may include: a top sub; a bottom sub; a mandrel coupled to the top sub and bottom sub and having an outer surface, at least a portion of which is corrugated; a grapple including one or more grapple members having a correspondingly corrugated inner surface and at least a portion of an outer surface of the grapple members including wickers for engaging an interior surface of the casing, wherein the grapple is configured to (i) axially and rotationally move along the corrugated outer surface of the mandrel and (ii) expand and collapse the grapple members responsive to axial movement relative to the mandrel; a piston slidably disposed within the mandrel and operatively coupled to the grapple; and a spring operative with the piston and biasing the grapple toward a collapsed position. Responsive to an increase in hydraulic pressure, the piston compresses the spring and axially moves the grapple, expanding the grapple members. Responsive to a subsequent decrease in hydraulic pressure, the spring decompresses and axially moves the grapple, collapsing the grapple members. The method may also include: activating the first cutting device; cutting a first casing segment; deactivating the first cutting device; activating the first spearing device; engaging the first spearing device with the first casing segment; removing the first casing segment from the wellbore.
[0009] This summary is provided to introduce a selection of concepts that are further described below in the detailed description. This summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used as an aid in limiting the scope of the claimed subject matter.
BRIEF DESCRIPTION OF DRAWINGS
[0010] FIG. 1 is a schematic representation of a downhole tool assembly according to embodiments of the present disclosure.
[0011] FIGS. 2-13 are various views of spearing devices according to embodiments of the present disclosure.
[0012] FIGS. 14-16 are schematic representations of downhole tool assemblies according to embodiments of the present disclosure.
DETAILED DESCRIPTION
[0013] In one aspect, embodiments disclosed herein relate to methods and apparatuses for cutting and retrieving easing from a wellbore. More specifically, methods and apparatuses disclosed herein relate to removing casing from a wellbore by making multiple casing cuts, and retrieving the casing joints in a well slot recovery operation. More specifically still, methods and apparatuses disclosed herein relate to making multiple casing cuts and retrieving multiple cut casing joints from a wellbore in a single trip.
[0014] The methods and apparatus disclosed herein include downhole tool assembly designs that may be used in the cutting and removing of casing segments from a wellbore. In accordance with embodiments disclosed herein, such operations, often referred to by those of ordinary skill in the art as slot recovery applications, include the use of a downhole tool capable of cutting casing segments, engaging the cut segments, freeing the segments, and then removing the segments from the wellbore in a single trip. Because multiple casing cuts may increase the efficiency of the operations, methods for activating and/or deactivating multiple downhole tools will be discussed below in detail.
[0015] Referring to FIG. 1 , a schematic representation of a fishing tool assembly 100 according to embodiments of the present disclosure is shown. Fishing tool assembly 100 includes a cutting device 101 , a spearing device 102 , and a jarring device 103 . Generally, cutting device 101 may be any type of cutting device capable of cutting cemented/uncemented casing known in the art. Spearing device 102 will be described in detail below. Jarring device 103 may include various types of jarring devices known in the art. Fishing tool assembly 100 may also include one or more additional components that may facilitate the slot recovery operation. The other components illustrated in FIG. 1 include a jarring device 104 , a packer 105 , and a stabilizer 106 . Those of ordinary skill in the art will appreciate that, depending on the requirements of the slot recovery operation, multiple cutting devices 101 , spearing devices 102 , packers 105 , stabilizers 106 , and other components, such as jar accelerators (not shown), may be used. Such alternative configurations of downhole tool assembly 100 will be discussed in detail below.
[0016] Generally, as noted above, cutting device 101 may include any type of cutting device capable of cutting casing known in the art. Such cutting devices typically include a plurality of arms 107 that may be actuated to extend from the body of the cutting device to engage casing. Typically, cutting devices include a plurality of cutting elements, teeth, or inserts disposed on the arms, such that upon actuation, the cutting elements contact the casing. Examples of cutting device actuation may include, spring loaded knives, expandable arms and/or blades with cuttings elements disposed thereon, and other cuttings devices known to those of ordinary skill in the art. As the tool string rotates, including rotation of the cutting device 101 , the cutting elements on arms 107 contact the casing and cut the casing to a depth defined by the extension of arms 107 and/or cutting elements. Thus, those of ordinary skill in the art will appreciate that a depth of cut into the casing may be controlled by limiting the extension of the arms and/or the protrusion from the arms of associated cutting elements. Depending on the thickness of the casing being cut, it may be beneficial to limit the depth of cut into the casing to, for example, 0 . 25 inches more than the casing thickness. In still other operations, it may be beneficial to decrease the depth of cut to an alternate depth, such as, for example, the thickness of the casing or a specified depth for the specific operation. Such depth of cut limits may find application in operations where sequentially smaller casing segments are disposed within the same region. Because the depth of cut may be limited, an engineer may elect to cut into a first casing segment (i.e., an inner casing segment) without cutting a second casing segment (i.e., an outer casing segment). U.S. Pat. No. 7,762,330, incorporated herein by reference to the extent not contradictory to embodiments herein, discloses examples of a cutting device 101 , a packer 105 , and a stabilizer 106 that may be used according to embodiments disclosed herein.
[0017] Referring to FIGS. 2 and 3 , a spearing device according to embodiments herein is illustrated. Spearing device 200 may include a top sub 201 and a bottom sub 202 . A mandrel 207 may be coupled to the top sub 201 and the bottom sub 202 , stationary with respect to the top and bottom subs 201 , 202 during operation of the spearing device 200 . In some embodiments, the mandrel 207 may be threadedly connected to the top sub 201 and the bottom sub 202 , stationary with respect to the top and bottom subs 201 , 202 during operation of the spearing device 200 .
[0018] Disposed circumferentially about the mandrel 207 is a grapple 206 . Grapple 206 may include one or more axial slots 208 defining grapple members 210 . At least a portion of the exterior surface of grapple members 210 includes wickers 212 , 216 ( FIG. 3 ) for engagement of the casing when the grapple members 210 are expanded. In some embodiments, grapple members 210 include wickers 212 biased in an upward direction to aid in lifting the casing from the wellbore. Grapple members 210 may also include wickers biased in a downward direction, minimizing slippage of the grapple relative to the casing during a jarring operation and aiding with re-cock of the jar, for example. This wicker design, when the grapple members 210 are engaged with the casing, allows application of axial force in both directions, as may be required by casing pulling, jarring operations, and jar re-cocking.
[0019] A portion of the outer surface of mandrel 207 is corrugated. Similarly, a portion of the inner surface of grapple members 210 is correspondingly corrugated. The respective corrugated surfaces may include ramps (non-helical) or buttress threads (helical), for example; use of threads may advantageously provide for rotational jerking of the spearing device. The corrugated surfaces may provide for axial and rotational movement of the grapple 206 along the corrugated outer surface of the mandrel 207 . Axial movement of the grapple 206 relative to mandrel 207 results in expansion and contraction of the grapple members 210 due to the corrugated surfaces.
[0020] The design of grapple 206 may depend on the type of corrugated surfaces used. For example, helical buttress threads may provide for use of a one-piece grapple 206 , where, as illustrated in FIG. 3 , a lengthwise axial slot 230 may allow grapple 206 to flex when the grapple members are expanded. The buttress threads may also allow for ease in assembly. Where the corrugated surfaces are ramps, a multi-piece grapple 206 may be required (e.g., two half-ring sections).
[0021] A piston 214 is slidably disposed within mandrel 207 and/or bottom sub 202 . Piston 214 is operatively coupled to grapple 206 via activation dogs 215 , where the respective portions of the activation dogs may push or pull on shoulder 235 of grapple 206 . Movement of piston 214 in an axial direction thus provides for expansion and contraction of grapple members 210 . A spring 211 is also provided, operative with piston 214 and biasing the grapple 206 toward a contracted or collapsed position. As illustrated, spring 211 abuts a shoulder 220 of bottom sub 202 and a shoulder 222 of piston 214 , and is in a biased, uncompressed condition.
[0022] Expansion of the grapple members 210 may be provided by a hydraulic activation system. For example, fluid flow is provided to spearing device 200 via throughbore 225 . The fluid flow passes through top sub 201 and mandrel 207 and enters nozzle 260 , resulting in applied pressure to a top surface of piston 214 . The applied pressure pushes piston 214 downward, compressing spring 211 , pulling grapple 206 axially with respect to mandrel 207 via activation dogs 215 , and expanding the grapple members 210 to engage an inner surface of casing to be removed, where the engagement provides a firm grip for the tool with the casing to facilitate the retrieval of the cut casing segment from the wellbore. When the hydraulic pressure is reduced, spring 211 decompresses and moves the grapple 206 upward, retracting grapple members 210 and disengaging from the casing wall.
[0023] Alternatively, the spring 211 may be positioned above the piston and biased toward a compressed condition, where activation of the piston may pull on spring 211 and deactivation of the system may result in the spring compressing, pulling on the piston and collapsing the grapple members.
[0024] Spearing device 200 may also include an anti-rotation locking system 213 , which may include one or more shear dogs 217 and shear screws 218 , among other components. To avoid rotation of grapple 206 relative to mandrel 207 , a shear dog 217 may be bolted to the mandrel 207 and disposed within a longitudinal slot 230 in grapple 206 . In some embodiments, the shear dog 217 may be coupled to the mandrel 207 and disposed within a longitudinal slot 230 in grapple 206 . Shear dog 217 incorporates an intentionally weakened face which can be sheared by application of right-hand (or alternatively left-hand) rotation of mandrel 207 , such as in the event of a grapple 206 “freeze” that cannot be released by conventional application of downwards force. Anti-rotation locking system 213 , when engaged, may prevent the grapple 206 from rotating when fully engaged with the casing. In some instances, however, it may be desirable to rotate grapple 206 , such as to free the spearing device 200 from the casing or other instances as readily envisionable by one skilled in the art. Thus, when disengaged (i.e., sheared), anti-rotation locking system 213 may provide for rotation of the grapple 206 , with typically less than 360 degrees of permitted rotation. The ability to unlock the rotatability of the grapple 206 may thus provide significant advantages during casing removal operations.
[0025] Referring now to FIGS. 4-13 , a spearing device according to other embodiments herein are illustrated. Spearing device 400 may include a top sub 401 , bottom sub 402 , spring 411 , piston 414 , mandrel 407 , grapple 406 (including grapple members and wickers (not illustrated)), activation dogs 415 , throughbore 425 , and anti-rotation locking system 413 , each as described above with respect to FIGS. 2 and 3 .
[0026] Spearing device 400 further includes a nozzle assembly 460 , disposed on a proximal end of piston 414 and including a nozzle carrier 462 partially axially spaced above piston 414 , a Bellville stack 464 , and a nozzle 466 . Spearing device 400 also includes a ratchet locking assembly 470 , disposed in the central bore of the top sub 401 and coupled with the top sub 401 . In some embodiments, the ratchet locking assembly 470 is threadedly connected with the top sub 401 . Locking assembly 470 may include an outer sleeve 472 , an intermediate sleeve 474 , an inner sleeve 476 , an end cap 478 , and a ratchet mechanism 480 , among other components as will be described below.
[0027] An upper end portion 477 of inner sleeve 476 , or a portion thereof, may be disposed within the intermediate sleeve 474 and may include wickers (not illustrated) on an outer surface thereof. Inner sleeve 476 extends axially through mandrel 407 , the lower end portion 479 ( FIG. 4 ) of the inner sleeve being disposed proximate nozzle assembly 460 .
[0028] Ratchet mechanism 480 may be disposed between overlapping portions of the inner and intermediate sleeves 476 , 474 . Ratchet mechanism 480 engages the wickers of the inner sleeve 476 and allows downward axial movement of inner sleeve 476 but prevents upward axial movement of inner sleeve 476 . Ratchet mechanism 480 may include a split ring 490 that includes inner ratchet teeth 492 , such as illustrated in FIGS. 10A and 10B , retained by circumferential garter springs 491 , for engaging the corresponding wickers 493 on inner sleeve 476 ( FIG. 10C ). The wickers are lengths of thread-like members that are tapered in only one direction. Thus, engagement between ratchet rings 490 and the wickers of inner sleeve 476 allows inner sleeve 476 to move in only one direction with respect to mandrel 407 .
[0029] As illustrated in FIGS. 4-6 , the spearing device is in a non-activated state. When spearing device 400 is to be used to hold and retrieve a piece of casing, such as retrieval to the surface, it may be desired or necessary to engage the holding ratchet mechanism 480 . This is performed by bleeding pressure from the tool string and hence the bottom hole assembly, inserting a “drop ball” at surface and pumping this ball 482 through the tool string to spearing device 400 , as illustrated in FIGS. 7-9 . Once the ball has seated within the lower end portion of the inner sleeve 476 , fluid pressure is applied to the spearing device 400 , resulting in the ball 482 and hence the ratchet mandrel (inner sleeve 476 ) being forced downwards a distance D; this applied force results in the shearing of ratchet mandrel shear screws 484 ( FIGS. 6 and 9 ). Prior to the ball drop, the spearing device may be hydraulically activated and deactivated as described above with respect to FIGS. 2 and 3 ; shearing of shear screws 484 as a result of the ball drop activates the ratchet locking mechanism.
[0030] The downward movement of ball 482 and ratchet mandrel 476 continues through the unidirectional wicker profile of the ratchet mechanism 480 , which may include retaining blocks or ratchet rings 490 retained by circumferential garter springs 491 ( FIGS. 10A-10C ) that allow radial movement sufficient to allow the ratchet mandrel 476 and corresponding ratchet retaining rings 490 with wicker profiles 492 to pass over each other and then snap back into retention position after each wicker tooth length.
[0031] Once inner sleeve 476 has moved sufficiently to come into contact with the nozzle carrier 462 , this effectively blocks the nozzle 466 and thus restricts fluid flow through the tool. Continued application of static pressure pushes the ball 482 , inner sleeve 476 , and nozzle carrier 462 downwards, thereby loading the Bellville spring stack 464 , and, in turn directly mechanically pushing the piston 414 and activation dogs 415 into contact with lower lip 435 of grapple 406 and drawing it downwards along mandrel 407 , thereby radially expanding the grapple 406 into contact with the casing as per the “pressure only” activation process described earlier. In addition to this directly applied mechanical force, fluid ports 488 above the drop ball's position in the inner sleeve 476 allows fluid pressure to be applied to the upper face of the piston assembly (piston 414 , and nozzle carrier 462 ), thereby resulting in an effective activation force, matching and possibly exceeding that of the fluid set engagement described above with respect to FIGS. 2 and 3 .
[0032] The purpose of the Bellville stack 464 is to prevent mechanical lockup of ratchet mandrel 476 and nozzle carrier 462 relative to piston assembly (piston 414 , activation dogs 415 , etc.) and hence, through transmission, grapple 406 and in turn the casing. This is required in order for the ratchet release mechanism to function properly (described below).
[0033] Referring now to FIGS. 11-13 , when the spearing device 400 is to be released after “activation with ratchet” as described above (i.e., deactivated), a second, larger diameter drop ball 494 is to be “dropped” into the tool string and allowed to come into contact with the ratchet release sleeve (intermediate sleeve 474 ), as illustrated in FIG. 13 .
[0034] Upon pressurization of the tool string and in turn application of fluid pressure to second ball 494 , sufficient force is applied to the ratchet release sleeve 474 to shear the ratchet release shear screws 496 (see FIGS. 6 and 13 ) coupling outer sleeve 472 and intermediate sleeve 474 . Once this occurs, the ratchet release sleeve 474 moves downward, bringing a release wedge profile feature 497 (integral with ratchet release sleeve 474 ) into contact with the corresponding ratchet rings/retaining blocks 490 internal wedge profiles (not shown). Continued downward travel of the ratchet release sleeve 474 forces the ratchet rings 490 to move outwards radially against the circumferential retaining garter springs 491 a distance that allows clearance between the retaining rings 490 and ratchet mandrel 476 wicker profiles. The resultant de-meshing of the wicker profile features allows free upward movement of the inner sleeve 476 causing the spring, piston, and grapple to return to the relaxed position, thereby disengaging grapple 406 from the casing, and thus releasing the casing.
[0035] During casing recovery operations, varied configurations of bottom hole assemblies including the above-described components may be used. Referring back to FIG. 1 , the operation of downhole tool assembly 100 during casing recovery operations will be described in detail. Initially, downhole tool assembly 100 is disposed in a wellbore, wherein downhole tool assembly 100 includes at least a cutting device 101 , a spearing device 102 , and a jarring device 104 . As described above, downhole tool assembly 100 may also include various other components, such as stabilizers 106 , packers 105 , and/or jarring accelerators 103 .
[0036] In one embodiment, downhole tool assembly 100 is disposed in a wellbore, and lowered to a portion of the wellbore where a casing cut is desirable. When downhole tool assembly 100 reaches the preferred casing section, cutting device 101 is activated by, for example, radio frequency transmission, ball drop actuation, pressure actuation, pressure pulse from the surface to the tool, such as through measurement while drilling tools, or any other actuation method known to those of ordinary skill in the art. Activation of cutting device 101 allows for a first casing segment to be cut. After the first casing segment is cut, cutting device 101 is deactivated, and spearing device 102 is activated. Spearing device 102 is engaged with the cut casing segment, and jarring device 104 is activated, so as to free the first casing segment. Because spearing device 102 is engaged with the first casing segment, downhole tool assembly 100 may be pulled up, and the casing segment removed from the wellbore.
[0037] In other embodiments, after the first casing segment is cut and spearing device 102 is engaged with the cut casing segment, cutting device 101 may be re-activated, and a second casing cut may be made. In certain embodiments, two casing cuts may be required, such that upon jarring the casing segment, the casing segment is freed. To increase the precision of the casing cuts, stabilizers 106 may be disposed on downhole tool assembly 100 to centralize cutting device 101 within the wellbore. By centralizing cutting device 101 , the individual cutters of cutting device 101 may be controlled, such that a preferred depth of cut may be maintained. Additionally, centralizing cutting device 101 may decrease the wear on the individual cutters, thereby increasing the life of cutting device 101 .
[0038] Referring to FIG. 14 , a downhole tool assembly 600 according to an alternate embodiment of the present disclosure is shown. In this embodiment, downhole tool assembly includes multiple cutting devices 601 a, 601 b, 601 c, a spearing device 602 , and a jarring device 604 . As described with respect to FIG. 1 , fishing tool assembly 600 may also include additional components, such as jarring accelerators 603 , packers 605 , and/or stabilizer(s) 606 .
[0039] In this embodiment, fishing tool assembly 600 may be disposed in a wellbore and activated similar to the activation of downhole tool assembly 100 of FIG. 1 . However, after a first casing segment is cut, and cutting device 601 a is deactivated, fishing tool assembly 600 may either be raised or lowered into the wellbore to a different depth, and additional cuts may be made. For example, in one embodiment, cutting device 601 a may be activated and deactivated so as to make a number of cuts, such as 3 or more cuts. After a number of cuts, the cutters of cutting device 601 a may be worn such that additional cuts can not be made. However, rather than remove fishing tool assembly 600 from the wellbore so that the cutters and/or cutting device 601 a may be replaced, cutting device 601 a may be deactivated, and cutting device 601 b may be activated, such that additional cuts may be made. Those of ordinary skill in the art will appreciate that the process of deactivating one of cutting devices 601 a, 601 b, or 601 c and activating a different cutting device 601 a, 601 b, or 601 c may occur in any order. For example, in certain embodiments, the lowest cutting device 601 c may be activated first, while in other embodiments, cutting device 601 a or 601 b may be activated first. The order of activation of cutting devices 601 a, 601 b, and 601 c will depend on the requirements of the casing cutting operation, as well as the depth of the casing segments within the wellbore.
[0040] Multiple cutting devices 601 may allow for multiple casing cuts to be made in a single trip of the tool string. Cutters of cutting devices 601 often wear down after two to three cuts. As such, the tool string would have to be tripped after two to three cuts. However, downhole tool assembly 600 may be capable of making multiple cuts, such as twelve or more cuts, thereby decreasing the number of trips of the tool string required to cut casing segments from the wellbore. In other embodiments, multiple cutting devices 601 may serve as redundant cutting devices, such that if one of the cutting devices 601 loses functionality or if the cutters of a first cutting device wear down prematurely, a second cutting device may be used. Those of ordinary skill in the art will appreciate that depending on the requirements of the casing cutting operation, the number of cutting devices 601 may vary. As such, bottom hole assemblies having one, two, three, four, or more cutting devices are within the scope of the present disclosure.
[0041] Referring to FIG. 15 , a downhole tool assembly 700 according to one embodiment of the present disclosure is shown. In this embodiment, downhole tool assembly 700 includes multiple cutting devices 701 a, 701 b, and 701 c, a spearing device 702 , and a jarring device 704 . Downhole tool assembly 700 also includes various optional components, such as a jarring accelerator 703 , packer(s) 705 , and a plurality of stabilizers 706 .
[0042] In this embodiment, the configuration of stabilizers 706 may allow for near cutting device centralization during activation of any of cutting devices 701 a, 701 b, and/or 701 c. As illustrated, stabilizers 706 are located at least above each of cutting devices 701 . As such, as cutting devices 701 are activated, the tool string may be centralized in a location close to cutting device 701 . By increasing stabilization and thus centralization of the tool string close to the individual cutting devices, the precision of cuts made by each cutting device 701 may be increased. Those of ordinary skill in the art will appreciate that the spacing of the individual stabilizers 706 will vary based on the type and/or size of casing being cut and the parameters of the downhole tool assembly 700 . However, by decreasing the space between cuttings devices 701 and stabilizers 706 , the centralization of the individual cutting devices 701 may be increased. Additionally, in certain embodiments, it may be beneficial to have stabilizers 706 disposed along the tool string both above and below cutting devices 701 .
[0043] Referring to FIG. 16 , a downhole tool assembly 800 according to one embodiment of the present disclosure is shown. In this embodiment, downhole tool assembly 800 includes multiple cutting devices 801 a and 801 b, multiple spearing devices 802 a and 802 b, and a jarring device 804 . Downhole tool assembly 800 also includes various optional components, such as a jarring accelerator 803 , packer(s) 805 , and a plurality of stabilizers 806 .
[0044] Downhole tool assembly 800 includes multiple spearing devices 802 a and 802 b, thereby increasing the number of cut casing segments that may be removed from the wellbore in a single trip. Downhole tool assembly 800 may thus be used in a cutting operation wherein cutting device 801 a is activated, and a first casing segment is cut. Spearing device 802 a may then be activated, thereby engaging spearing device 802 a with the first casing segment, and jarring device 804 may be activated to free the cut casing segment from the wellbore. Subsequently, second cutting device 801 b may be activated, and a second casing segment may be cut. Spearing device 802 b may then be activated, so as to engage the cut casing segment. Jarring device 803 may then be reactivated, and the second casing segment may be freed from the wellbore. The above described method of cutting, spearing, and jarring may be repeated as many times as the cutters on individual cutting devices 801 allow. As such, multiple casing segments may be cut, speared, and removed from the wellbore in a single trip.
[0045] Those of ordinary skill in the art will appreciate that the order of operation of the individual components may be varied, without departing from the scope of the present disclosure. For example, in one embodiment, cutting device 801 a may be activated, and a first casing cut made. Cutting device 801 a may then be deactivated, and the tool string lowered axially within the wellbore. Cutting device 801 a may then be reactivated, and a second casing cut may be made. This process of making multiple casing cuts may be repeated for the life of the cutters on cutting device 801 a. After the desired number of casing cuts are made, spearing device 802 a may engage one or more of the cut casing segments, and jarring device 804 may be activated to help free the casing cuts.
[0046] In other embodiments, after the plurality of casing cuts by cutting device 801 a have been made, cutting device 801 b may be activated, and a plurality of additional casing cuts may be made. Similar to the function of cutting device 801 a, cutting device 801 b may be activated and deactivated until the desired number of casing cuts has been made. After all of the casing cuts have been made by both cutting devices 801 a and 801 b, one or more of spearing devices 802 a and 802 b may be activated to engage the cut casing segments. In one embodiment, both spearing devices 802 a and 802 b may be activated, while in other embodiments only one of spearing devices 802 a or 802 b may be required to allow for the removal of the cut casing segments from the wellbore. Those of ordinary skill in the art will appreciate that it may only be necessary to engage the lowest axial spearing device, in this embodiment 802 b, when removing the casing segments. Because the higher axial casing segments will be pulled up to the surface of the wellbore as the lowest axial casing segment is pulled upwardly, only one spearing device 802 b may be required to remove multiple casing segments. However, in certain embodiments, it may be beneficial to engage multiple spearing devices 802 with the cut casing segments so as to increase the contact area between the spearing device 802 and the casing being removed. By increasing the surface area of the contact between the spearing device 802 and the casing, more casing may be removed from the wellbore in a single trip.
[0047] Fishing tool assemblies as described above include a spearing device, or grapple, that is configured to engage drill pipe or casing. The spearing device may be internal to the cylindrical body of a cutting tool, or in other embodiments, may be a separate component of a fishing tool assembly. In such an embodiment where the spearing device is a separate component of a fishing tool assembly, the spearing device may be disposed axially upward of a cutting tool, and may engage the drill pipe or casing before, during, and/or after the cutting operation. Thus, drill pipe may be held in place during operation, and as the cutting tool assembly is removed from the wellbore, the cut section of the drill pipe may also be removed from the wellbore.
[0048] Any of the above described embodiments may allow for multiple casing segments to be removed from a wellbore in a single trip. The order of operation of specific embodiments of the present disclosure may vary according to the requirements of the cutting operation. For example, in certain embodiments, multiple casing cuts may be made, followed by a single spearing and jarring. In other embodiments, multiple casing cuts may be followed by multiple spearing and jarring. Accordingly, all of the casing cuts may be made initially, followed by spearing the lowest axial cut casing segment, jarring one or more of the segments, and then removing the freed casing segments from the wellbore. Those of ordinary skill in the art will appreciate that each cut casing segment may be jarred loose separately. In other embodiments, it may be beneficial to cut a desired number of casing segments, spear the segments, and then cut additional segments. In such an embodiment, multiple spearing devices may facilitate the cutting and removal of the cut casing segments from the wellbore.
[0049] Advantageously, embodiments of the present disclosure may allow for casing segments to be cut, speared, and removed from a wellbore in a single trip of the tool string. By providing multiple cutting devices that may be sequentially activated by the use of, for example, radio frequency transmission, sequentially sized ball drop actuation, pressure pulse actuation, and/or pressure thresholds, a plurality of casing segments may be cut, speared, and removed from the wellbore. Such activation may be remotely and selectively controlled from the rig floor. By removing multiple casing segments in a single trip, valuable time may be saved in slot recovery operations. Additionally, by decreasing the number of trips of the tool string to cut and recover casing segments, the cost of a slot recovery operation may be decreased.
[0050] The hydraulically actuated spears disclosed herein, such as illustrated in FIGS. 2 and 4 , may provide for a greater expansion of the grapple members, allowing an increased initial clearance, and facilitating insertion of the tool assembly within the casing. The greater expansion may also provide for use of an improved teeth (wickers) design, and for increased gripping forces, allowing a greater weight carrying capacity as compared to mechanically activated spearing devices, and facilitating removal of larger and/or more sections of casing in a single trip. For example, in the case of upward pulling, the force applied is directly transmitted from the casing to top sub 201 and in turn to mandrel 207 . This force pulls mandrel 207 upward relative to the now “stuck” grapple 206 , thereby increasing the radial expansion forces acting upon the grapple, and thus increasing the gripping force between the grapple wickers and the casing.
[0051] While the disclosure includes a limited number of embodiments, those skilled in the art, having benefit of this disclosure, will appreciate that other embodiments may be devised which do not depart from the scope of the present disclosure. Although only a few example embodiments have been described in detail above, those skilled in the art will readily appreciate that many modifications are possible in the example embodiments without materially departing from this invention. Accordingly, all such modifications are intended to be included within the scope of this disclosure. In the claims, means-plus-function clauses are intended to cover the structures described herein as performing the recited function and not only structural equivalents, but also equivalent structures. Thus, although a nail and a screw may not be structural equivalents in that a nail employs a cylindrical surface to secure wooden parts together, whereas a screw employs a helical surface, in the environment of fastening wooden parts, a nail and a screw may be equivalent structures. It is the express intention of the applicant not to invoke 35 U.S.C. §112, paragraph 6 for any limitations of any of the claims herein, except for those in which the claim expressly uses the words ‘means for’ together with an associated function.
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A spearing device for use in removing casing is disclosed. The spearing device includes: a top sub; a bottom sub; a mandrel, coupled to the top and bottom subs, having an outer corrugated surface; a grapple having a correspondingly corrugated inner surface and an outer surface including wickers for engaging an interior surface of the casing; a piston disposed within the mandrel and operatively coupled to the grapple; and a spring operative with the piston and biasing the grapple toward a collapsed position. The grapple: (i) axially and rotationally moves along the corrugated outer surface of the mandrel and (ii) expands and collapses responsive to axial movement relative to the mandrel. Responsive to increases in hydraulic pressure, the piston compresses the spring and axially moves and expands the grapple. Responsive to subsequent decreases in hydraulic pressure, the spring decompresses and axially moves and collapses the grapple.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention generally relates to a semiconductor memory device, and more specifically, to a semiconductor memory device compatible with various systems having different kinds of data input/output (I/O) bandwidths.
2. Description of the Prior Art
A conventional memory device has a fixed I/O bandwidth. A system using a memory device may have different bandwidths depending on manufacturing companies or its usage. Therefore, the conventional memory device requires an additional interfacing device to be used in a system having different data bandwidth from that of the conventional memory device.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide a memory device configured to control a bandwidth of I/O data.
According to an embodiment of the present invention there is provided a memory device, including: a plurality of data I/O buffers connected one by one to a plurality of I/O ports; a switch array including a plurality of switches for connecting the plurality of data I/O buffers to a plurality of sense amplifier arrays; and a switch controller for receiving an external control signal to control the data I/O buffers and the plurality of switches.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram illustrating a structure of a memory device according to a preferred embodiment of the present invention.
FIG. 2 is a structural diagram illustrating a main bitline pull-up controller, a cell array block, and a column selection controller of FIG. 1 .
FIG. 3 is a structural diagram illustrating the main bitline pull-up controller of FIG. 2 .
FIG. 4 is a structural diagram illustrating a main bitline load controller of FIG. 2 .
FIG. 5 is a structural diagram illustrating a column selection controller of FIG. 2 .
FIG. 6 is a detailed structural diagram illustrating a sub cell block of FIG. 2 .
FIGS. 7 a and 7 b are timing diagrams illustrating read/write operations of the sub cell block of FIG. 6 .
FIGS. 8 a through 8 d are structural diagrams illustrating a data I/O buffer and a data pad of FIG. 1 .
FIGS. 9 a through 9 b are structural diagrams illustrating a switch array, a data I/O buffer and a sense amplifier array of FIG. 1 .
FIG. 10 is a structural diagram illustrating the switch array of FIG. 9 .
FIG. 11 is a structural diagram illustrating the sense amplifier array and a column decoder of FIG. 1 .
FIGS. 12 a through 12 b are detailed structural diagrams of a switch controller of FIG. 1 .
FIGS. 13 a through 13 d are timing diagrams illustrating operations of the switch array, the sense amplifier array and the data I/O buffer of FIG. 1 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention will be described in more detail with reference to the accompanying drawings.
FIG. 1 is a block diagram illustrating a structure of a memory device which can control an I/O bandwidth according to a preferred embodiment of the present invention. The memory device of the present invention comprises a cell array block 100 , a main bitline pull-up controller 11 for pulling up a main bitline included in the cell array block 100 to a positive voltage, a column selection controller 12 for connecting the main bitline to a data bus 20 , a sense amplifier array 30 connected to the data bus 20 , a switch array 400 for controlling the sense amplifier array, and a data I/O buffer 500 for exchanging data with the sense amplifier array 30 . Additionally, the memory device of the present invention comprises a column decoder 200 for controlling the switch array 400 , and a switch controller 300 for controlling the switch array 400 and the data I/O buffer 500 . The memory device further comprises I/O ports or data pads 600 connected to the data I/O buffer 500 for inputting and outputting a plurality of data bits (data signals are referred to herein as “data bits”).
FIG. 2 is a structural diagram illustrating a cell array block 100 of FIG. 1 . The cell array block 100 comprises one or a plurality of main bitline load controllers 13 and a plurality of sub cell blocks 110 .
FIG. 3 is a structural diagram illustrating the main bitline pull-up controller 11 of FIG. 2 . The main bitline pull-up controller 11 comprises a PMOS transistor having a gate to receive a control signal MBPUC, a source connected to a power source VPP(VCC) and a drain connected to a main bitline MBL.
The main bitline pull-up controller 11 pulls up the main bitline MBL to a voltage VPP(VCC) in a precharge operation.
FIG. 4 is a structural diagram illustrating the main bitline load controller 13 of FIG. 2 . The main bitline load controller 13 comprises a PMOS transistor having a gate to receive a control signal MBLC, a source connected to a power source VPP(VCC) and a drain connected to the main bitline MBL.
The main bitline load controller 13 , as a resistant device connected between the power source VPP(VCC) and the main bitline MBL, determines a potential of the main bitline according to the amount of current flowing through the main bitline load controller 13 in data sensing action.
One or more of the main bitline load controllers 13 are connected to one main bitline MBL. When two or more main bitline load controllers 13 are connected to one main bitline, the same number of sub cell blocks 110 are assigned to a main bitline load controller 13 and the main bitline load controllers 13 are evenly placed apart from each other.
FIG. 5 is a structural diagram illustrating the column selection controller 12 of FIG. 2 . The column selection controller 12 is a switch for connecting the main bitline MBL to a data bus. On/off operations of the column selection controller 12 are controlled by control signals CSN and CSP.
FIG. 6 is a detailed structural diagram illustrating the sub cell block 110 of FIG. 2 .
The sub cell block 110 comprises a sub bitline SBL, and NMOS transistors N 1 , N 2 , N 3 , N 4 and N 5 . The sub bitline SBL is connected in common to a plurality of unit cells, each of which is connected to a wordline WL<m> and a plateline PL<m>. The NMOS transistor N 1 for regulating a current has a gate connected to a first terminal of the sub bitline SBL, and a drain connected to the main bitline MBL. The NMOS transistor N 2 has a gate connected to a control signal MBSW, a drain connected to a source of the NMOS transistor N 1 and a source connected to a ground. The NMOS transistor N 3 has a gate connected to a control signal SBPD, a drain connected to a second terminal of the sub bitline SBL and a source connected to a ground. The NMOS transistor N 4 has a gate connected to a control signal SBSW 2 , a source connected to the second terminal of the sub bitline SBL and a drain connected to a control signal SBPU. The NMOS transistor N 5 has a gate connected to a control signal SBSW 1 , a drain connected to the main bitline MBL and a source connected to the second terminal of the sub bitline SBL.
When a unit cell is to be accessed, only the sub bitline connecting the unit cell is connected to the main bitline. Here, the sub bitline SBL is connected to the main bitline MBL by the NMOS transistor N 5 . Accordingly, memory read/write operations can be performed even with a smaller amount of load corresponding to one sub bitline rather than a larger amount of load corresponding to the whole bitline.
A potential of the sub bitline SBL is grounded when the control signal SBPD is activated. The control signal SBPU regulates a voltage to be provided to the sub bitline SBL. The control signal SBSW 1 regulates the flow of a signal between the sub bitline SBL and the main bitline MBL. The control signal SBSW 2 regulates the flow of a signal between the control signal SBPU and the sub bitline SBL.
The sub bitline SBL connected to a gate of the NMOS transistor N 1 regulates a sensing voltage of the main bitline. The main bitline MBL is connected to the power source VPP(VCC) via the main bitline load controller 13 (see FIG. 4 ). When a control signal MBSW becomes “high”, current flows from the power source VPP(VCC), through the main bitline load controller 13 , the main bitline MBL and the NMOS transistors N 1 and N 2 , to a ground. Here, the amount of the current is determined by a voltage of the sub bitline SBL connected to the gate of the NMOS transistor N 1 . If data of a cell is “1”, the amount of the current becomes larger, thereby decreasing the voltage of the main bitline MBL. If data of a cell is “0”, the amount of the current becomes smaller, thereby increasing the voltage of the main bitline MBL. Here, the cell data can be detected by comparing the voltage of the main bitline MBL with a reference voltage. Detecting the cell data is performed in the sense amplifier array 30 .
FIG. 7 a is a timing diagram illustrating a write operation of the sub cell block of FIG. 6 .
If an address transits in t 1 , a chip starts a writing operation according to an address transition detection signal ATD.
In t 2 and t 3 , data of a cell is detected by activating a wordline WL and a plateline PL. When data of the cell is “high”, the voltage of the sub bitline rises, and current flowing through the NMOS transistor N 1 becomes larger. As a result, the voltage of the main bitline MBL becomes lower than a reference level. On the other hand, if data of the cell is “low”, the voltage of the sub bitline SBL falls, and current flowing through the NMOS transistor N 1 becomes smaller. As a result, the voltage of the main bitline MBL becomes higher than a reference level.
In t 4 , a self-boosting operation is prepared by setting the control signal SBSW 2 at a “high” level. In t 5 , “high” level data is written into the cell. If the control signal SBSW 2 is “high”, the control signal SBSW 2 , the wordline WL and the sub bitline SBL are driven to “high” levels when the control signal SBPU becomes “high”. Voltages of these signals rise higher than the voltage VPP by the self-boosting operation. In t 5 , since the wordline WL and the bitline SBL are high, and the plateline PL is low, data “1” is automatically written into the cell.
In t 6 , “low” level data is written. If the control signals SBPD and SBSW 2 are inactivated, and the control signal SBSW 1 is activated, data “0” provided from the main bitline MBL is supplied to the sub bitline SBL. Here, since the voltage of the plateline PL is “high”, data “0” is written into the cell. If a signal provided from the bitline is “1”, the voltage of the plateline is “high”, and the voltage of the sub bitline SBL is also “high”. As a result, data “1” written in t 5 is maintained without change.
In order to improve a sensing margin by stabilizing an initial state of a cell storage node, the wordline WL is activated earlier than the plateline. Then, the wordline WL is activated in t 2 , and then the plateline PL in t 3 . In t 2 , the control signal SBPD is maintained at the “high” level, the data of the cell is initialized as “0”. After initialization, the control signal SBPD is inactivated to the “low” state, and the plateline is activated to the “high” level. After the data “0” is written in t 6 , the wordline WL is inactivated earlier than the plateline PL by inactivating the wordline WL in t 7 , and then the plateline PL in t 8 (not shown).
FIG. 7 b is a timing diagram illustrating a read operation of the sub cell block of FIG. 6 .
The operations in the intervals t 2 through t 6 are as described in FIG. 7 a . The read operation is different in that data detected in a sense amplifier (not shown) is not externally outputted.
In t 5 and t 6 , a restore operation is performed. In the restore operation, the data detected in the sense amplifier (not shown) is temporarily stored, and then re-written into the cell. Since the data stored in the sense amplifier is provided to the cell through the bitline, the restore operation is similar to the write operation. In t 5 , the data “1” is automatically written in the same manner of the write operation. In t 6 , the data “1” written in the section t 5 is maintained if the data “1” is provided to the bitline, and the data “0” is written if the data “0” is provided to the bitline.
FIGS. 8 a through 8 d are structural diagrams illustrating a data I/O buffer and a data pad of FIG. 1 .
Referring to FIG. 8 a , data pads 610 and 620 comprise DQ_ 0 through DQ_ 15 . The data pads 610 and 620 are connected to a data I/O buffer 500 (see FIG. 1 ). The data I/O buffer 500 is divided into a lower byte region 510 and an upper byte region 520 . DQ_ 0 through DQ_ 7 are connected to the lower byte region 510 , and DQ 8 through DQ 15 are connected to the upper byte region 520 . DQ_ 15 in the upper byte is used as an A_LSB signal which is provided to the switch controller 300 (see FIG. 1 ). The A_LSB signal corresponds to an additional address signal. For example, when a system bus processes data by 1 byte, and a memory device processes data by 2 bytes, data of 2 bytes should be stored in a memory address for efficiency of the memory device. However, since the system processes data in 1 byte, 2 bytes should be differentiated and then processed by the memory device. Here, by using the control signal A_LSB, data inputted/outputted to and from the memory device can be processed by 1 byte.
FIG. 8 b has the same structure as FIG. 8 a . However, it is different in that the A_LSB signal is provided from one of the bits DQ_ 8 through DQ_ 14 included the upper byte except the most significant bit DQ_ 15 .
A preferred embodiment shown in FIG. 8 c comprises a plurality of upper byte regions unlike the preferred embodiments shown in FIGS. 8 a and 8 b . A control signal which is one of A 0 — LSB, . . . , A n — LSB, exists in each of the upper byte regions. These signals are outputted from the most significant bit in each upper byte region. The control signals A 0 — LSB through A n — LSB are used as additional address signals like the control signal A_LSB of FIG. 8 a.
FIG. 8 d has the same structure of FIG. 8 c . However, it is different in that the control signals A 0 — LSB through A n — LSB are provided from one of the bits included in each upper byte region except the most significant bits.
FIGS. 9 a through 9 b are structural diagrams illustrating the switch array 400 , the data I/O buffer 500 and the sense amplifier array 30 of FIG. 1 .
The data I/O buffer 500 is connected to an I/O bus. The I/O bus is divided into a lower byte bus LB_BUS and an upper byte bus UB_BUS. The lower byte bus LB_BUS comprises m bits, and the upper byte bus LB_BUS comprises n bits. The lower byte bus LB_BUS is connected to the lower byte region 510 of the data I/O buffer 500 . The upper byte bus UB_BUS is connected to the upper byte region 520 of the data I/O buffer. Each sense amplifier included in the sense amplifier array 30 is divided into a lower byte region 31 and an upper byte region 32 .
The switch array 400 comprises a first switch 410 , a second switch 420 and a third switch 430 . The first switch 410 connects the lower byte bus LB_BUS to the lower byte region 31 of the sense amplifier array 30 . The second switch 420 connects the lower byte bus LB_BUS to the upper byte region 32 of the sense amplifier array 30 . The third switch 430 connects the upper byte bus UB_BUS to the upper byte region 32 of the sense amplifier array 30 . The second switch 420 transmits n bits of sense amplifier bits to the lower byte bus LB_BUS.
FIG. 9 b additionally shows control signals in the switch array 400 and the data I/O buffer 500 of FIG. 9 a . The lower byte region 510 of the data I/O buffer 500 is controlled by ORing the control signals LB_EN and Byte_EN. The on/off operations of the first switch 410 are controlled by a control signal LB_SW_EN. The on/off operations of the second switch 420 are controlled by a control signal Byte_SW_EN. The on/off operations of the third switch 430 are controlled by a control signal UB_SW_EN.
FIG. 10 is a structural diagram illustrating the switch array 400 of FIG. 9 . According to a preferred embodiment of the present invention, the first switch 410 , the second switch 420 and the third switch 430 have the same structure. Each switch comprises a predetermined number of transmission gates arranged in parallel. A transmission gate included in the first switch 410 is controlled by the control signal LB_SW_EN. A transmission gate included in the second switch 420 is controlled by the control signal Byte_SW_EN. A transmission gate included in the third switch 430 is controlled by the control signal UB_SW_EN.
FIG. 11 is a structural diagram illustrating the sense amplifier array 30 and a column decoder 200 of FIG. 1 . As described above, each sense amplifier in the sense amplifier array 30 is included either in the lower byte region 31 or in the upper byte region 32 . The sense amplifier array is controlled by output signals Y<0>˜Y<n> of the column decoder 200 .
FIGS. 12 a through 12 b are detailed structural diagrams of the switch controller 300 of FIG. 1 . The switch controller 300 receives control signals A_LSB, /Byte, /LB, /UB, and output signals of the column decoder to provide control signals LB_SW_EN, UB_SW_EN, Byte_SW_EN, LB_EN and UB_EN.
Referring to FIG. 12 a , the circuit of FIG. 12 a generates control signals LB_EN and UB_EN provided to the data I/O buffer 500 and control signals Byte_EN, Byte_BUF, A_LSB_ 0 and A_LSB_ 1 used in the intermediate process.
The /Byte signal determines activation of the lower byte region. The Byte_BUF signal is generated by buffering the /Byte signal, and the Byte_EN signal is generated by inverting the Byte_BUF signal.
The /LB signal determines activation of lower bytes. The LB_EN signal is generated by performing an AND operation on (“ANDing”) the buffered /LB signal and the Byte_BUF signal and then by inverting the signal obtained from the AND operation. When the /Byte signal is “low”, the Byte_BUF signal is “low”. As a result, the LB_EN signal becomes “high” regardless of the level of the /LB signal. However, when the /Byte signal is “high”, the Byte_BUF signal is “high”. As a result, the level of the LB_EN signal is regulated by that of the /LB signal.
The /UB signal regulates activation of upper bytes. The UB_EN signal is generated by ANDing the Byte_BUF signal and a signal generated by buffering and then inverting the /UB signal. When the /Byte signal is “low”, the Byte_BUF signal is “low”. As a result, the UB_EN signal becomes “low” regardless of the level of the /LB signal. However, when the /Byte signal is “high”, the Byte_BUF signal is “high”. As a result, the level of the UB_EN signal is regulated by that of the /UB signal.
The A_LSB signal converts data of upper bytes into data of lower bytes. The A_LSB_ 1 signal is generated by ANDing the A_LSB signal and the Byte_EN signal. The A_LSB_ 0 signal is generated by ANDing the A_LSB signal and the Byte_EN signal and then inverting the signal obtained by the AND operation. When the /Byte signal is “low”, the Byte_EN signal is “high”, one of the A_LSB_ 1 or the A_LSB_ 0 signals becomes “high”, and the other signal becomes “low”. However, when the /Byte signal is “high”, the Byte_EN signal is “low”. As a result, the level of the A_LSB_ 0 signal becomes “high”, and the level of the A_LSB_ 1 signal becomes “low” regardless of the level of the A_LSB signal.
The circuit of FIG. 12 b outputs control signals LB_SW_EN, UB_SW_EN and Byte_SW_EN by using the signals A_LSB_ 0 , A_LSB_ 1 , UB_EN and Byte_EN of FIG. 12 a and the output Y<n> of the column decoder 200 .
The control signal LB_SW_EN for controlling the on/off operation of the first switch 410 FIG. 9 b is obtained by ANDing the A_LSB_ 0 signal and the output Y<n> of the column decoder 200 . The control signal Byte_SW_EN for controlling the on/off operations of the second switch 420 of FIG. 9 b is obtained by ANDing the signals A_LSB_ 1 and Byte_EN and the output Y<n> of the column decoder 200 . The control signal UB_SW_EN for controlling the on/off operations of the third switch 430 of FIG. 9 b is obtained by ANDing the inverted Byte_EN signal, the UB_EN signal and the output Y<n> of the column decoder 200 . The function of each signal is as follows.
FIGS. 13 a through 13 d are timing diagrams illustrating operations of the switch array 400 , the sense amplifier array 30 and the data I/O buffer 500 .
FIG. 13 a shows the timing diagram when the first switch 410 is activated, and data in the lower byte region 31 of the sense amplifier array 30 is provided to the lower byte region 510 of the data I/O buffer 500 . In this state, the /Byte signal is inactivated to the “high” level, the /LB signal is activated to the “low” level, and the /UB signal is inactivated to the “high” level. Here, the Byte_EN signal becomes “low”, the Byte_BUF signal becomes “high”, the LB_EN signal becomes “high”, the UB_EN signal becomes “low”, and the A_LSB_ 0 becomes “high”, and the A_LSB_ 1 becomes “low” (see FIG. 12 a ).
Since the A_LSB_ 0 signal is “high”, the LB_SW_EN signal becomes “high”. Since the UB_EN signal is “low”, the UB_SW_EN becomes “low” (see FIG. 12 b ). As a result, the upper byte region 520 of the data I/O buffer 500 is inactivated (see FIG. 9 b ). If the LB_EN signal becomes “high”, a signal obtained by performing an OR operation on (“ORing”) the signals LB_EN and Byte_EN becomes “high”. As a result, the lower byte region 510 of the data I/O buffer 500 is activated (see FIG. 9 b ). Here, data in the lower byte region 31 of the sense amplifier array 30 is outputted into the lower byte region 510 of the data I/O buffer 500 .
FIG. 13 b shows the timing diagram when the third switch 430 is activated, and data in the lower byte region 32 of the sense amplifier array 30 is provided to the lower byte region 520 of the data I/O buffer 500 . In this state, the /Byte signal is inactivated to the “high” level, the /LB signal is inactivated to the “high” level, and the /UB signal is activated to the “low” level. Here, the Byte_EN signal becomes “low”, the Byte_BUF signal becomes “high”, the LB_EN signal becomes “low”, the UB_EN signal becomes “high”, and the A_LSB_ 0 becomes “high”, and the A_LSB_ 1 becomes “low” (see FIG. 12 a ).
Since the A_LSB_ 0 signal is “high”, the LB_SW_EN signal becomes “high”. Since the UB_EN signal is “high”, the UB_SW_EN becomes “high” (see FIG. 12 b ). As a result, the upper byte region 520 of the data I/O buffer 500 is activated (see FIG. 9 b ). If the LB_EN signal becomes “low”, a signal obtained by ORing the signals LB_EN and Byte_EN becomes “low”. As a result, the lower byte region 510 of the data I/O buffer 500 is inactivated (see FIG. 9 b ). Here, data in the upper byte region 32 of the sense amplifier array 30 is outputted into the upper byte region 520 of the data I/O buffer 500 .
FIG. 13 c shows the timing diagram when the first switch 410 and the third switch 430 are activated, data in the lower byte region 31 of the sense amplifier array 30 is provided to the lower byte region 510 of the data I/O buffer 500 , and data in the upper byte region 32 of the sense amplifier array 30 is outputted into the upper byte region 520 of the data I/O buffer 500 . The detailed operation is omitted because it is similar to the above-described operation.
FIG. 13 d shows the timing diagram when the first switch 410 and the second switch 420 are activated in turn. In this state, the /Byte signal is inactivated to the “low” level, and the /LB signal and the /UB signal are inactivated to the “high” level. Here, the Byte_EN signal becomes “high”, the Byte_BUF signal becomes “low”, the LB_EN signal becomes “high”, the UB_EN signal becomes “low”, and the A_LSB_ 0 becomes a signal obtained by inverting the A_LSB signal, and the A_LSB_ 1 becomes the same value of the A_LSB signal (see FIG. 12 a ).
Since the output Y<n> of the column decoder 200 is activated, the Byte_EN signal is “high”, the UB_SW_EN signal is “low”, the LB_SW_EN is at the same level with the A_LSB_ 0 , and the Byte_SW_EN is at the same level with the A_LSB_ 1 . If the A_LSB signal is “high”, the LB_SW_EN becomes “low”, and the Byte_SW_EN becomes “high”. If the A_LSB signal is “low”, the LB_SW_EN signal becomes “high”, and the Byte_SW_EN signal becomes “low” (see FIG. 12 b ). As a result, the upper byte region 520 of the data I/O buffer 500 is inactivated, and the lower byte region 510 is activated (see FIG. 9 b ).
An example is described where data of a memory device is processed by 2 bytes, and data of a system bus is processed by 1 byte. Here, an address of a system bus is designated every 1 byte of data, and an address of a memory device is designated every 2 bytes of data. The number of address bits used in the system should be one more than that used in the memory device. The data bit A_LSB in the upper byte region is used as an address bit in order to compensate for the insufficient address bit (see FIGS. 8 a through 8 d ).
The process of storing data into a memory is as follows. An address of a system bus is designated every 1 byte of data, and the system bus is provided to the lower byte region 510 of the data I/O buffer 500 . Here, if the A_LSB_ 0 signal becomes “high”, the A_LSB_ 1 becomes “high”, the LB_SW_EN becomes “low”, and the Byte_SW_EN becomes “high”. As a result, the lower byte region 510 of the data I/O buffer 500 becomes connected to the lower byte region 31 of the sense amplifier array 30 via the first switch 410 (see FIGS. 9 b , 12 a and 12 b ). If the A_LSB signal becomes “low”, the A_LSB_ 0 signal becomes “high”, the LB_SW_EN becomes “high”, and the Byte_SW_EN signal becomes “low”. As a result, the lower byte region 510 of the data I/O buffer 500 becomes connected to the upper byte region 32 of the sense amplifier array 30 via the second switch 420 .
The process of reading data from the sense amplifier array 30 to the data I/O buffer 500 is performed as described above.
Accordingly, the semiconductor memory device of the present invention does not need extra interfacing devices by effectively changing the data I/O bandwidth of the memory device.
While the present invention is susceptible to various modifications and alternative forms, specific embodiments have been shown by way of example in the drawings and described in detail herein. However, it should be understood that the invention is not limited to the particular forms disclosed. Rather, the invention covers all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined in the appended claims.
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A semiconductor memory device with adjustable I/O bandwidth includes a plurality of data I/O buffers connected one by one to a plurality of I/O ports, a switch array including a plurality of switches for connecting the plurality of data I/O buffers to a plurality of sense amplifier arrays, and a switch control unit for receiving external control signals to control the data I/O buffer and the plurality of switches.
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BACKGROUND OF THE INVENTION
[0001] The invention relates to a starter for an internal combustion engine. By way of example, one such starter is described in the Kraftfahrtechnischen Taschenbuch (Motor vehicle manual) produced by Bosch, 25 th edition, page 986, in the form of a pre-engaged Bendix starter, which is operated via a so-called pull-in relay. This relay carries out the pulling-in functions, that is to say engaging the pinion of the starter motor in the toothed rim on an internal combustion engine, and switching the main current of the starter motor. In this case, a distinction can be drawn between two possible processes when the pinion engages in the toothed rim: in about 20%-30% of switching operations, one tooth of the pinion engages in a gap in the toothed rim, while, in approximately 70%-80% of the switching operations, one tooth of the pinion strikes a tooth on the toothed rim during engagement, and the engagement process must be assisted by an engagement spring. This known starter design admittedly requires only a single relay and can therefore be produced at relatively low cost, but on the other hand it results in very difficult working conditions for the switching process for the high motor current on the switching contact which connects the motor windings to the voltage source. Particularly in the case of partially discharged batteries and as the mechanical wear on the engagement parts increases, the dynamic response when switching on the main starter current can decrease to such an extent that the contacts are welded by arcs which occur during the switching process. On the other hand, if the pinion engages directly in the engine toothed rim, the dynamic response of the switching process and the contact wear resulting from it may possibly be high, depending on the design of the starter, when starting from an initial tooth-in-gap position.
[0002] In order to improve the switching-on process, particularly in the case of high-power starters, it is also known from the abovementioned reference for the motor current to be switched on in two stages in so-called pre-engaged starters wherein, in a first stage, the pinion of the starter is moved against the toothed rim of the engine, and the armature of the starter motor is at the same time fed with a reduced current, as a result of which the armature and, with it, the pinion, rotate during the engagement process, thus simplifying the engagement process. The engagement mechanism is in this case provided with a ratchet which closes a further switching contact of the relay and, via this, the main current circuit of the motor, only at the end of the engagement process of the pinion. This allows the engagement process and the switching of the main current of the motor to be carried out in two separate processes, but the design of the pull-in relay is more complex and more susceptible to defects, from the mechanical and electrical points of view.
SUMMARY OF THE INVENTION
[0003] The starter according to the invention, has the advantage that the processes for engagement of the pinion on the one hand and the switching of the motor current on the other hand are completely decoupled by the use of separate means for this purpose, in particular by the use of separate relays, in which case, the types of relay can be optimally matched to the respective process steps. However, it is also possible to use suitable semiconductor components, preferably transistors or GTO (Gate Turn Off) thyristors, for switching relatively high currents for all of the switching means, or for individual switching means. In particular, this makes it possible to completely separate the switching function for the high main motor current during starting of the internal combustion engine from the engagement process, thus avoiding reactions from the engagement dynamics on the contact system of the relay. The speed at which the contacts close is in this case independent of the engagement situation.
[0004] It is particularly advantageous for the switching relay in the main circuit of the starter motor to be activated by the engagement relay itself at the end or shortly before the end of the engagement movement, and in this case for the starter motor to be connected directly to the voltage source. With little additional complexity, this results in exact interaction between the engagement movement of the pinion and the process of switching on the main starter current at the end of the engagement movement. The engagement relay is for this purpose expediently equipped with a holding winding and a separate pull-in winding, which jointly operate a switching contact for activation of the switching relay. The holding winding and the engagement winding are preferably seated on the same relay core, and are in this case selectively switched in the same sense or in opposite senses. If they are switched in the same sense, the required total flux is achieved with a smaller number of turns and/or a lower excitation current while, if the fluxes are opposite, the winding with the lesser flux can be used to damp the switching process. The numbers of turns and the excitation currents for the holding winding and the pull-in winding are in this case expediently chosen such that the holding winding produces the switching process of the engagement relay with a large number of turns and an adequate excitation current, while the pull-in winding is equipped with considerably fewer turns, but carries a considerably higher excitation current, which is sufficient to easily rotate the armature during engagement.
[0005] One particularly simple and cost-effective circuit design is obtained by current being passed through the starter motor in a single stage, in which case the pull-in winding of the engagement relay is connected in series with a series winding of the starter motor, as a bias resistance, and both windings of the engagement relay jointly switch a make contact, via which current is passed to the winding of the switching relay, and the starter motor is supplied with the entire motor current at the end of the pull-in movement of the engagement relay. As is known, an arrangement such as this requires an engagement spring which, in conjunction with a steep-pitched thread, in particular when the pinion and the toothed rim are in a so-called tooth-on-tooth position, assists the engagement process, before suddenly switching on the main current for the motor.
[0006] A particularly protective engagement process is achieved by passing current through the starter motor in two stages in a manner which is known in principle, in which case, in a first switching stage, a limited rotation current for the starter armature flows via a normally-closed contact and the pull-in winding of the engagement relay. In a second stage, current is subsequently passed through the separate switching relay via a make contact of the engagement relay at or shortly before the end of the pulling-in movement of the relay armature, and the full motor current is supplied to the starter motor. In this case, the two separate relays can be optimally designed in accordance with the different requirements.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] Further details and advantageous refinements of the invention will become evident from the dependent claims and the description of the exemplary embodiments, which will be explained in more detail in the following description and are illustrated in the drawings, in which:
[0008] FIG. 1 shows an outline illustration of a pre-engaged Bendix starter with a series winding,
[0009] FIG. 2 shows a circuit diagram of a conventional embodiment of a starter through which current is passed in a single stage,
[0010] FIG. 3 shows a circuit diagram of an embodiment according to the invention of a starter through which current is passed in a single stage,
[0011] FIG. 4 shows a first circuit diagram of an embodiment according to the invention of a starter through which current is passed in two stages,
[0012] FIG. 5 shows a second circuit diagram of an embodiment according to the invention of a starter through which current is passed in two stages,
[0013] FIG. 6 shows an outline illustration of the spatial arrangement and connection of a starter according to the invention with an engagement relay and a switching relay, and
[0014] FIG. 7 shows an outline illustration of the spatial arrangement and connection of a starter as shown in FIG. 6 , with an additional pilot control relay for passing current through the engagement relay.
DETAILED DESCRIPTION
[0015] FIG. 1 schematically illustrates the mechanical design of the starter 10 according to the invention, in the form of a pre-engaged Bendix starter for an internal combustion engine. The starter 10 has a starter motor 12 whose output drive shaft 14 has a steep-pitched thread 16 which interacts with a corresponding female thread in a driver shaft 18 . Alternatively, the output drive shaft 14 is driven via an epicyclic gearbox, which is connected in between, but is not illustrated. The driver shaft 18 is firmly connected to the outer ring of a freewheeling ring 20 , whose inner ring is fitted with a pinion 22 . The pinion 22 and the freewheeling mechanism 20 are mounted on the output drive shaft 14 such that they can move axially as far as a stop 24 . The pinion 22 in this case engages in a toothed rim 26 of an internal combustion engine, which is not illustrated. The axial movement takes place with the aid of a relay arrangement 28 , which is illustrated in detail in the following figures and acts on the freewheeling mechanism 20 via a direction-changing lever 29 and an engagement spring 32 . A battery is used as the voltage source 34 for the arrangement; the negative pole 31 of the battery is connected to ground, and its positive pole 30 is connected on the one hand directly and on the other hand via an ignition/starter switch 36 to the relay arrangement 28 . A series winding 38 is fed via the relay arrangement and is connected to ground via brushes 40 , 42 and via the commutator 44 of the motor. The armature of the starter motor 12 is annotated 46 , and its stator is annotated 48 .
[0016] FIG. 2 shows a circuit diagram of a conventional embodiment of a starter through which current is passed in a single stage. In this case, the positive pole 30 of the voltage source is connected to an engagement relay 49 , on the one hand via the ignition/starter switch 36 and a connection 50 , and on the other hand directly. This engagement relay 49 contains a holding winding 52 and a pull-in winding 54 , which are wound in the same sense, are wound on the same core, and are both connected at one winding end to the connection 50 . The other winding end of the holding winding 52 is connected to the negative pole 31 and to ground, and the corresponding other winding end of the holding winding 54 is connected to the negative pole 31 and to ground via the series winding 38 and the armature 46 of the starter motor 12 . The holding winding and the pull-in winding jointly operate a make contact 56 in the engagement relay 49 , via which the starter motor 12 is connected directly to the positive pole 30 as soon as the relay armature has pulled in entirely or virtually entirely, and the pinion 22 has engaged in the toothed rim 26 .
[0017] The holding winding 52 and the pull-in winding 54 in this known arrangement together carry out the task of engagement of the pinion 22 in the toothed rim 26 on the internal combustion engine, and at the same time the function of switching the main current for the starter motor 12 . If, during this process, a tooth of the pinion 22 meets a gap in the toothed rim 26 , then only a small amount of force is required for engagement, and the dynamic response during switching of the contact 56 is relatively high. On the other hand, the dynamic response during switching of the contact 56 is very low when, during engagement, a tooth on the pinion 22 strikes a tooth on the toothed rim 26 , as a result of which the engagement spring 32 , as shown in FIG. 1 , must also be stressed during engagement, and only a small amount of energy is available for operation of the make contact 56 . In consequence, relatively long-lasting arcs and welding can occur, which adversely affect the operation of the starter, at least in the long term.
[0018] FIG. 3 shows the circuit diagram of an embodiment according to the invention of a starter through which current is passed in a single stage, and which overcomes the difficulties described above. In principle, with an engagement relay 57 and its connection to the DC voltage power supply system 30 , 31 , the design of the circuit arrangement corresponds to that in FIG. 2 , but in this arrangement the relay contact 56 does not carry out the switching function for the high motor current, but only for passing current through the winding 58 of a switching relay 60 , which then switches the motor current via its make contact 62 . In addition, this arrangement operates in only one stage, with the pinion 22 engaging in the toothed rim 26 in the same way as in the arrangement shown in FIG. 2 , and with the motor current being switched on completely at the end or shortly before the end of the engagement movement of the pinion 22 . In contrast to the arrangement shown in FIG. 2 , in addition to the engagement work for the pinion 22 , however, the engagement relay 57 only has to operate the lightly loaded contact 56 , and the actual process of switching on the motor current is carried out by the switching relay 60 , as a result of which the functions of engagement and switching are completely separate, and the engagement process does not cause any reaction on the contact system of the switching relay 60 .
[0019] FIG. 4 shows a circuit arrangement for passing current through a starter motor 12 in two stages. In this case, instead of the engagement relay 57 for passing current in a single stage, as shown in FIG. 3 , there is an engagement relay 64 with a normally-closed contact 66 and a make contact 68 . The fixed connections of the contacts 66 and 68 can in this case be connected in parallel via a pilot control relay 70 to the positive pole 30 , with one end of the relay winding being connected to the negative pole 31 and to ground, and the other end being connected via the connection 50 and the ignition/starter switch 36 to the positive pole 30 of the DC voltage power supply system. The holding winding 52 of the engagement relay 64 is likewise connected via the pilot control relay 70 to the positive pole 30 and to the negative pole 31 of the DC voltage power supply system.
[0020] In this embodiment, the two windings 52 and 54 of the engagement relay 64 are wound in opposite senses, with the holding winding 52 having a considerably greater number of turns than the pull-in winding 54 and being excited with a sufficiently high current in order to carry out the engagement process for the pinion 22 on its own, despite the flux in the opposite direction in the pull-in winding 54 . In this case, the pull-in winding 54 advantageously damps the dynamic response of the engagement movement, and at the same time supplies a sufficiently high excitation current to the series winding 38 of the starter motor in order to rotate this slightly, and to simplify the engagement process, or to allow the engagement process. In this arrangement, an engagement spring can additionally be used in order to assist the engagement process.
[0021] Once again, the current flow through the starter motor 12 is provided by the switching relay 60 , independently of the operation of the engagement relay 64 . For this purpose, current is passed through the winding 58 of the switching relay 60 at the end or close to the end of the switching movement of the engagement relay 64 , by closing its make contact 68 and opening the normally-closed contact 66 , such that the switching relay 60 is supplied with its predetermined operating current via its make contact 62 , without the engagement process adversely affecting the starter motor 12 . Because the normally-closed contact 66 has been opened, there is no current through the pull-in winding 54 of the engagement relay 64 , while its holding winding 52 remains excited until the ignition/starter switch 36 opens, and thus ensures that the starting process is continued.
[0022] The use of a pilot control relay 70 for the operation of the circuit arrangement as shown in FIG. 4 is not absolutely essential, and current can also be passed through the engagement relay 64 directly via the ignition/starter switch, analogously to the circuit arrangement shown in FIG. 3 . On the other hand, in the first current-flow phase, the motor current via the pull-in winding 54 is in the order of magnitude of up to 200 A, which means that it is expedient to use a pilot control relay to bypass the ignition/starter switch 36 in the first stage of the current flow, at least for high-power starting motors.
[0023] FIG. 5 shows a variant of the circuit arrangement from FIG. 4 , which differs from the previously described embodiment in that the excitation current for the winding 58 of the switching relay 60 does not flow via the pilot control relay 70 , but is tapped off directly from the supply line to the positive pole 30 of the voltage source. This admittedly has the disadvantage that an additional connection is required between the engagement relay 64 and the switching relay 60 , but on the other hand it reduces the magnitude of the current via the engagement relay 64 , and there is therefore no need for the pilot control relay 70 , at least for relatively small types of motor. All the other functions of the circuit arrangement shown in FIG. 5 correspond to those in FIG. 4 , and do not need to be explained again.
[0024] In order to explain illustrations in FIGS. 6 and 7 , FIGS. 3 to 5 show additional connection points with the reference symbols 50 i , 50 k , 50 m and 50 n . In this case, the connection point 50 i is connected to the fixed connection of the relay contact of the pilot control relay 70 , the connection point 50 k is connected to the winding connection of the switching relay 60 , the connection point 50 m is connected to one connection, and the connection point 50 n is connected to the other connection, of the make contact of the engagement relay 57 , or 64 . These reference symbols make it easier to interpret the illustrations in FIGS. 6 and 7 , in which case the switching contacts which are normally in practice in the form of double contacts or have a contact plate, are likewise illustrated schematically.
[0025] FIG. 6 shows the design configuration of a starter according to the invention with a single-stage current flow corresponding to FIG. 3 . In this case, the starter motor 12 , the engagement relay 57 and the switching relay 60 form one unit 72 , in which case either both relays 57 and 60 or one of them are or is integrated permanently in the housing of the starter motor 12 , or is or are detachably connected to it. The internal design of the engagement relay 57 , of the switching relay 60 and of the starter motor 12 are indicated symbolically by the respective connection points. For example, the engagement relay 57 receives its start signal via an external connection from the ignition/starter switch 36 , as a result of which the make contact 56 is closed, and the connection points 50 m and 50 n are connected to one another for excitation of the relay.
[0026] In the switching relay 60 , the positive pole 30 is connected via the make contact 62 to the connection point 45 on the relay, and this is externally connected to the starter motor 12 and, via its series winding 38 , to the negative pole 31 , and to ground.
[0027] FIG. 7 shows the spatial arrangement of a starter according to the invention through which current is passed in two stages, corresponding to FIG. 4 or 5 . In this case, the pilot control relay 70 , the engagement relay 64 , the switching relay 60 and the starter motor 12 form one unit 74 . Once again, the relays 70 , 64 and 60 are selectively integrated individually or jointly in the housing of the starter motor 12 , or are detachably connected to it. The illustration of the connection points and of the contacts corresponds to FIGS. 4 and 5 , which differ only in the current supply to the make contact 68 in the engagement relay 64 . The connection 50 n in the engagement relay 64 is in this case selectively connected either to the connection point 50 i on the pilot control relay 70 , or directly to the positive pole 30 of the voltage source.
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The invention relates to a starter ( 10 ) for an internal combustion engine, comprising a starter motor ( 12 ) which can be coupled to the internal combustion engine by means of a pinion ( 22 ), and a device for engaging the pinion ( 22 ) in a gear rim ( 26 ) of the internal combustion engine and connecting the starter motor ( 12 ) to a DC voltage supply system ( 30, 31 ). In order to disconnect the sequence of operations, the device has separate means, in particular separate relays ( 57, 64; 60 ), for engaging the pinion ( 22 ) on one hand and turning on the starter motor on the other when the internal combustion engine is started, thus preventing reactions of the engagement dynamics on the contact system when the motor current is switched.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention concerns a cassette acceptance device with the capability to recognize the state of the cover of the cassette opening or bay in a printing mail processing apparatus or a similar printing billing or mail processing apparatus.
2. Description of the Prior Art
Conventional thermotransfer franking machines of the type T1000 and Optimal commercially available from Francotyp Postalia & Co. KG do not have piracy protection for consumable material, i.e. an ink ribbon in a cassette. By means of an encoder, a microprocessor controller allows an ink ribbon conveyor to establish that an encoder disc is fastened on the same axle as a friction wheel, and the latter is likewise rotated. When the flap of the cassette bay is opened, a simple mechanism is activated and the friction wheel is raised from the ink ribbon of the cassette, which allows the cassette to be removed without causing damage. The operation of the machine is interrupted given a faulty ink ribbon transport.
The arrangement of a switch on the security housing of a franking machine is known from EP 1300807 A2; for different reasons, namely for protection for an operator so that if fingers of the operator are inserted into an opening of the franking machine, such as Ultimail®, also available from Francotyp Postalia & Co. KG, they are not crushed by the transverse movement of the printing carriage. This solution is only suitable for inkjet printing franking machines, particularly for exchange of ink cartridges via the opening that can be sealed by a flap. The flap is equipped with a stop that, upon opening of the flap, activates a switch inside the security housing, causing current supply to a motor of the transverse movement mechanism of the printing module to be interrupted. Adoption of this solution for thermotransfer franking machines with ink ribbon cassettes is not possible without difficulty since there no movement of the printing module nor an exchange of an ink cartridge. Moreover, recently mail carrier regulating authorities have begun to require a higher printing quality that is supported by piracy protection measures from the franking machine manufacturer (such as a chip applied on the consumable material).
DE 199 58 946 A1 discloses a thermotransfer franking machine with a microcomputer to which a contact or sensors is/are applied in order to indirectly establish the presence of exchanged consumable material based on a physical characteristic by means of an evaluation (implemented by the microprocessor) of measured sensor data and stored operating data. If a chip with identifying data is not arranged on the cassette, a chip card (provided for this purpose) must then be inserted into a slot of a chip card reader in order to read the identifying data. The exchange is thus permitted only some time later. Moreover, exactly where the sensors are arranged and which of these are used for evaluation is dependent on the franking machine type, because usually already-present sensors are used that do not specifically detect an exchange of consumable material.
A detector is known from DE 199 58 941 A1 that also reliably detects the removal or exchange of consumable material when the apparatus is deactivated and is not supplied with system voltage. For this purpose, the detector uses a typical lithium battery that supplies a memory with a memory-retention voltage. There is no discussion, however, as to exactly where the sensor is arranged relative to the cassette. According to one variant, piracy protection is possible for thermotransfer cassettes in the form of an electronically-programmable chip, but this presumes a precise alignment of the cassette with the chip relative to a reading unit (chip reader) and the application of a contact force on order to securely read the data. Given the use of a chip for the purpose of piracy protection, in operation an electrical voltage is applied across the chip. This document does not address preventing removal or circumvention of the cassette during the operating state, such that access to the activated reading unit is possible. Such an access would at least lead to operational interferences or to manipulation or even to destruction of the chip.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a cassette acceptance device for an ink ribbon cassette that is equipped with an electronically-programmable chip in order to provide a piracy protection, which can be used in a thermotransfer franking machine that is equipped to prevent the measures for piracy protection from being penetrated or attacked. A further object is to fashion a cassette bay in order to ensure the contacting of the chip during the operation. A correct alignment of the cassette relative to the chip reading unit and the application of a contact force on the chip contacts should ensue in an optimally simple and reliable manner. The shape of the cassette flap should contribute to the alignment of the cassette and state recognition of the flap position. It is a further object to design the protection against external access to the chip reading unit during the operating state in a manner that allows detection of the operating state in connection with the piracy protection.
The above object is achieved in accordance with the present invention by a cassette acceptance device for use with a printing mail processing apparatus having an apparatus housing with an exteriorly accessible cassette bay therein, closeable by a flap, the device including a sensor disposed to interact with a flap finger at an underside of the flap to detect, before exchange of a cassette with respect to the cassette bay, that flap position for which a cassette extraction is possible, and a microprocessor connected to the sensor that detects the position of the cassette flap dependent on the signal from the sensor. The microprocessor, given a closed cassette flap indicated by the sensor signal, causing voltage to be supplied to a chip reader unit mounted in the cassette bay and, given an open cassette flap indicated by the sensor signal, causing the voltage to be disconnected from the chip reader unit before each cassette exchange.
For a cassette bay that is sealed by a flap, in accordance with the invention the cassette acceptance mechanism has a sensor that can detect the flap position before the exchange in which a cassette removal is possible. After the exchange and closing of the flap, parameter, usage and operating data stored via the chip attached to the cassette are read in a known manner. A mechanism is provided in the area of the sensor carrier, this mechanism translating the opening of the cassette flap into a movement of a sensor activation element. A sensor carrier supports the sensor and is integrally molded on one of the sides of the shaped cassette bay part above this part. The mechanism is fastened on a chassis such that it can move opposite to an elastic force. A microprocessor is operationally connected with the sensor and detects the position of the cassette flap by means of the sensor and in cooperation with the mechanism. The microprocessor is programmed to enable voltage supply from the microprocessor to the chip reader unit only when the cassette flap is closed. Given a closed cassette flap, external access to the chip reader unit is not possible. By means of mechanical elements of the flap and/or the shape of the cassette bay part, the cassette is pressed into a position in which a locking element acts on an edge of the cassette by means of a pressure element so that a secure electrical contacting of the chip with the chip reader unit exists. By means of the arranged locking element, the cassette is brought into a precise position relative to the chip reader unit and a force sufficient for a secure electrical contacting is thereby applied. Moreover, mechanical guide elements for alignment of the cassette relative to the chip reader unit in connection with the application of a contact force are used in the cassette bay. On its underside, the cassette bay has at least one flap finger and at least one elevation that are disposed between both flap arms with support pins. The elevation is fashioned so that the cassette is forced into the closed flap position in the locking position. Upon opening of the cassette flap, external access to the chip reader unit is prevented until a sensor signal is switched via the activation element upon triggering of the sensor and the voltage supply of the chip reader unit is deactivated. Access to and extraction of the cassette are therefore possible only when the voltage supply of the chip reader unit has been deactivated.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a thermotransfer franking machine with the flap of the cassette bay in place in accordance with the invention.
FIG. 2 is a plan view of the thermotransfer franking machine of FIG. 1 without the cassette flap in place.
FIG. 3 is a view of the cassette flap from below.
FIG. 4 is a perspective view of a thermotransfer franking machine of FIG. 1 with the cassette flap opened.
FIG. 5 a is a perspective view of the shaped cassette bay part from the front and lower right in accordance with the invention.
FIG. 5 b is a rear view of the shaped cassette bay part in accordance with the invention.
FIG. 6 is a detail of the mechanism to the left, next to the cassette bay in accordance with the invention.
FIG. 7 shows sensor for detecting the cassette flap position or encoder position in accordance with the invention.
FIG. 8 a is a front view of the slider shown in FIG. 5 b.
FIG. 8 b is a side view of the slider shown in FIG. 5 b.
FIG. 9 is a thermotransfer ink ribbon cassette with a chip in a perspective view from the rear and above left, suitable for use in the inventive thermotransfer franking machine in accordance with the invention.
FIG. 10 is a perspective view of the feed table and chassis of the thermotransfer franking machine in accordance with the invention.
FIG. 11 is a perspective view of the encoder wheel mounting in accordance with the invention.
FIG. 12 is a side view of the feed table and chassis of the thermotransfer franking machine in accordance with the invention.
FIG. 13 is a front view of the feed table and chassis of the thermotransfer franking machine in accordance with the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows a perspective view of a thermotransfer franking machine 1 from the front and upper right. The thermotransfer franking machine 1 is equipped on its right side 7 and on its upper part 10 with a flap 5 for the cassette bay of the franking machine 1 , and on its left side with a weighing plate 2 of a scale component. All housing parts are manufactured, for example, from colored plastic. The transport of mail pieces to and from the franking machine 1 ensues on the feed table 4 of the franking machine on the front side of the franking machine 1 , from the left side and to the right side 7 .
FIG. 2 shows a plan view of a thermotransfer franking machine without the flap. The flap was removed on the front side of the upper part 10 . Parts that are covered in FIG. 1 are thereby visible, such as: the left external housing wall 3 near the cassette bay on the left side near the weighing plate 2 and the covering 30 for a left-side cassette acceptance mechanism; the thermotransfer ink ribbon cassette 8 with a locking element 11 for precise positioning of the cassette 8 in a locked position, and with a pressure element 12 for the cassette 8 for applying a contact force; the thermotransfer print head 9 ; the covering 60 for a right-side mechanism of the cassette acceptance and the right external housing wall 6 near the cassette bay on the right side 7 of the franking machine. The left-side covering 30 and the right-side covering 60 respectively have slit-shaped openings 31 and 61 for the left and for the right flap arms of the flap 5 (not shown), respectively. A damping element 59 for braking the flap opening speed of the cassette flap is mounted on the cover 30 for the left-side of the cassette acceptance mechanism. External access to the chip reader unit is thereby prevented for a sufficiently-long time and the voltage supply of the chip reader unit can be deactivated in this time period. The aforementioned parts—except for the locking element 11 and the pressure element 12 —are connected with the upper part 10 and belong to the upper housing shell. The feed table 4 belongs to the lower housing shell of the thermotransfer franking machine. Both the upper housing shell and the lower housing shell can be manufactured by injection molding.
FIG. 3 shows a view of the cassette flap 5 from below. In a depression 56 , the cassette flap 5 has a cavity 57 , corresponding to the size of the pressure element 12 , which exerts a pressure force on the chip (not visible). A flap finger 53 and projections 541 , 542 are arranged between the two flap arms 51 and 52 . The left flap arm 52 is fashioned as a gearwheel segment in order to interact with the gearwheel of the damping element (not shown). Bearing pins 511 , 521 for a connection (not shown, but rotatable on the axle 55 ) with the upper housing shell are respectively integrally molded on the flap arms 51 and 52 . A spring 58 that produces a resilient and elastic force counter to the closing of the flap 5 is arranged at one of the bearing pins 511 . The cassette flap 5 likewise can be manufactured by injection molding. In the event that the ink ribbon cassette 8 has not been correctly inserted by the operator, the projections 511 , 542 on the underside of the cassette flap 5 force the ink ribbon cassette 8 into the locked position, at the latest upon closing of the cassette flap 5 .
FIG. 4 shows a perspective view from the front and above right of a thermotransfer franking machine 1 with flap 5 opened. The flap 5 is shown opened in the direction toward the upper part 10 . The flap 5 has flap arms 51 , 52 arranged on both sides of its underside. The right external housing wall 6 on the cassette bay merges on the right side 7 into the right side wall of the upper shielding element of the franking machine, and into the right cover 60 . A first step 62 (aligned as above) is provided that corresponds to the flap shape on its underside. The left external housing wall 3 on the cassette bay merges into the upper shell of the franking machine and into the left cover 30 . A second step 32 (aligned as above) is provided that corresponds to the flap shape on its underside and accommodates the damping element 59 thereon. The damping element 59 is formed of a braking drum and a gearwheel that is engaged with the gearwheel segment of the left flap arm 52 . Upon closing of the flap, the arms 51 , 52 of the cassette flap 5 respectively dip into the corresponding slit-shaped openings 31 and 61 in the steps 32 and 62 of the left and right covers 30 and 60 . On its underside, the flap 5 has a flap finger 53 serving as an activation element for a mechanism that acts on a sensor (not visible) that detects the state of the flap 5 . A disconnection of the supply voltage already ensues upon lifting off the front flap edge by a few millimeters (approximately 10 to 20 mm travel), i.e. before an access to the chip reader unit or, respectively, the extraction of the cassette 8 is possible. A correctly-placed ink ribbon cassette 8 is precisely arranged by a locking element 11 resiliently mounted on the shaped cassette bay part 17 . The ink ribbon cassette 8 is held in a locking position by the pressure element 12 , the pressure element 12 being arranged at the tip of the locked element 11 (not visible) and a positive application of a sufficient contact force on the chip of the ink ribbon cassette 8 is effected.
A chip reader unit (covered) is arranged in an opening on the rear housing wall 173 of the cassette bay 17 . The cassette bay is laterally bordered on both sides by a right inner housing wall 171 and a left inner housing wall 172 . The left inner housing wall 172 has an opening 18 for the friction wheel 38 , which is raised from the ink ribbon cassette in the representation according to FIG. 4 , i.e. given an opened flap 5 .
FIG. 5 a is a perspective view of the shaped cassette bay part from the front lower right. Respective mechanisms located under the cover and steps of the upper housing shell rest (in a manner not shown) on the chassis between the left and right inner housing walls 172 and 171 and the left and right outer housing walls on the shaped cassette bay part 17 , while the associated sensors rest on respective integrally-molded sensor carriers 174 and 175 . The sensor 36 for detection of the cassette flap state/encoder position rests on the external sensor carrier 174 of the shaped cassette bay part 17 , the sensor carrier 174 being integrally-molded on the left inner housing wall 172 . The inner space (cassette bay) of the shaped cassette bay part 17 is bordered by the right inner housing wall 171 , the left inner housing wall 172 and the rear housing wall 173 . A molding 1731 on the edge between the left inner housing wall 172 and the inside of the rear housing wall 173 forms an outer wall of a channel 1734 for a slider 43 (shown in other figures), of which only its top slope 434 is visible in FIG. 5 b . A quadrilateral opening 1732 in the rear housing wall 173 accommodates the chip reader unit 14 . A circular opening 1733 in the rear housing wall 173 is provided for the winding mandrel of the cassette coil (not shown). The left inner housing wall 172 has an opening 18 and a lateral guide 1721 for correct positioning of the cassette upon insertion. The right inner housing wall 171 likewise has a lateral guide. An upper housing wall 176 likewise has guides 1761 , 1762 as positioning aids. The upper housing wall 176 laterally merges into the left and right inner housing wall and to the rear into the rear housing wall 173 and not only stabilizes the cassette bay but also carries integrally-molded fasteners (obscured in FIG. 5 b ) for the elastic locking element 11 , on the free ends of which the pressure element 12 is integrally molded. A frame 177 (protruding into the inner space of the cassette bay) for the print head is integrally-molded on the lower end of the rear housing wall 173 in the middle thereof. The space enclosed by the lateral integrally-molded sensor carriers 174 and 175 is sealed from below by base plates 178 , 179 , which are respectively integrally-molded on the rear housing wall 173 between the left and right inner housing walls 172 and 171 . For low-friction mail piece transport, it is advantageous for the base plate 178 to gently rise outwardly relative to the feed table 4 . Downstream in terms of mail flow, the base plate 178 terminates in a thickened edge 1781 before the frame 177 for the print head. For ejection of the mail pieces, it is advantageous for the base plate 179 to begin with a thickening 1791 after the frame 177 , the thickening 1791 accommodating non-actuated rollers 1792 and 1793 and supporting them such that they can rotate.
FIG. 5 b shows a rear view of the shaped cassette bay part with a channel-shaped molding 1734 on its outer wall 1730 . The channel 1734 centrally has a guide channel 1734 for the rail 432 and a catch or dog 4331 on the front side of the slider 43 . In the shown position, a force can be exerted by the pressure spring 44 on the mechanism (encoder wheel mounting, not shown) via the slider 43 . The mechanism can move across the slider 43 by virtues of a first force F 1 acting on the slider 43 . A pressure spring 44 is arranged on the slider 43 so that the pressure spring 44 relaxes and the first elastic force F 1 is effectively exerted on the mechanism when opening of the cassette flap 5 ensues. The slider 43 is movably arranged between the shaped cassette bay part 17 and the chassis in the channel 1734 of the shaped cassette bay part 17 and, in the representation according to FIG. 5 b , is shifted upwardly. Upon activation the top slope 434 proceeds counter to the dynamic effect (force action) of the pressure spring 44 . The slider 43 has an actuation slope 437 for the mechanism (located under the cover and steps of the upper housing shell) that is supported on the chassis. Operation thereof is initiated by a change of the cassette flap position (stable), detected by the sensor 36 that rests on the sensor carrier 174 of the shaped cassette bay part 17 . The sensor carrier 174 is externally integrally-molded on the left inner housing wall 172 and has a sensor activation lever 361 that is brought into engagement with the mechanism. The other sensor carrier 175 of the shaped cassette bay part 17 likewise can have a sensor in order to detect the ejection of mail pieces. The back side 1730 of the rear housing wall 173 of the shaped cassette bay part 17 has a fastener 1763 for the locking element 11 resiliently mounted on the upper housing wall 176 . The back side 1730 of the rear housing wall 173 of the shaped cassette bay part 17 shows the circular opening 1733 passing through it and a circuit board 13 , which enables the electrical connection and mechanical fastening of the chip reading unit. The shaped cassette bay part 17 can be manufactured by injection-molding.
FIG. 6 shows details of the mechanism that is arranged to the left, next to the cassette bay under the left cover 30 . The mechanism has an encoder wheel mounting that is fastened on the chassis such that it can rotate around a rotation axle 39 . The slider 43 is forcibly connected with the encoder wheel mounting, which can move counter to a second resilient force. Given an opened flap 5 , the slider 43 between the chassis (not shown) and outer channel wall 1731 thus serves for force transfer to the encoder wheel mounting, which has a rocker 333 mounted such that it can rotate on the axle 39 , the axle 39 being oriented transverse to the mail piece transport direction. Given a closed cassette flap (not shown), a force F is exerted on the top slope 434 of the slider 43 by the flap finger 53 . The slider 43 is therefore shifted downwardly (as shown in the representation according to FIG. 6 ) and thus can exert no force on the encoder wheel mounting. A tension spring 37 is fastened on the shaped cassette bay part 17 near the left outer housing wall and engages the encoder wheel mounting 33 so that the tension spring 37 is tensed when the cassette flap 5 is opened, so a second resilient force F 2 is effectively exerted on the mechanism. The sensor actuation element itself has a spring and, in this exemplary embodiment, is formed as a sensor actuation lever 361 mounted such that it can resiliently rotate. Due to the force effect of the tension spring 37 , a crank disk 3347 on the end of a fourth rocker 334 of the encoder wheel mounting is raised relative to the level of the feed table 4 , thereby activating the sensor actuation lever 361 . The sensor actuation lever 361 thereby performs a rotational movement around an axle 360 , and a vane 362 integrally-molded on another end of the sensor actuation lever 361 projects from the detection region of the sensor electronic of the sensor electronic housing 363 . At the same time, a friction wheel 38 is pushed through an opening 18 in the left inner housing wall 172 and through a lateral window opening of the ink ribbon cassette onto the ink ribbon. The friction wheel 38 is rigidly coupled with an encoder wheel (not shown) via a common bolt 34 supported in at least one rocker 333 . When the ink ribbon is advanced (due to a printing event), this leads to a rotation movement that is transferred to the encoder wheel and is detected by an encoder (not shown).
A sensor 36 for detection of the position of the cassette flap 5 (i.e., the encoder position) is shown in perspective view, from the front and upper right, in FIG. 7 . A spring 364 holds the sensor actuation lever 361 in the shown position when it is not activated. This is the case when the cassette flap 5 is opened. The spring 364 is designed, for example, as a torsion spring with one spring leg situated in a hole 3611 of the sensor actuation lever 361 and the other spring leg resting on a sensor electronics housing 363 . The sensor electronic 5 includes, for example, a light barrier that (in the shown position) is interrupted by the vane 362 integrally molded on the lever 361 . For example, a sensor of the type Photointerrupter LG-413L from the company Kodenshi Corp. can be used. Given suitable dimensions of the encoder wheel mounting 33 , the friction wheel 38 performs a sufficiently-large pivot movement that also actuates the sensor actuation lever 361 , due to its lever length between its axle 360 and its outermost end.
A front view of the slider 43 is shown in FIG. 8 a and a side view is shown in FIG. 8 b . The slider 43 enables the pivot motion and, given opening of the flap 5 , serves for force transfer to the encoder wheel mounting. A pressure spring 44 shifts the slider 43 upwardly with a predetermined force and thereby slides the axle 34 of the encoder wheel mounting 33 into an elongated (oblong or slotted) hole of the chassis 40 , causing the encoder position to change to such a degree that the friction wheel 38 is no longer in contact with the cassette ink ribbon. Given an opened cassette flap 5 , no force F is exerted on the top slope 434 of the slider planar body by the flap finger 53 . The slider planar body 431 has a flat, smooth back side and at least one rail 432 for guidance to its front side, which is integrally molded running in the movement direction. A second, narrow guide rail 4311 can be integrally molded on the front side of the slider planar body 431 . Its upper end is bordered by the top slope 434 and its lower end is bordered by a hollow cylinder that is integrally molded so as to curve forward. The wall 436 of the hollow cylinder has a fastening opening 438 for a pressure spring 44 . Given an opened cassette flap 5 , either a top 435 of the hollow cylinder or an actuation slope 437 of the slider planar body can come into engagement with at least one part of the mechanism located behind the left cover 30 of the upper housing shell. Between its middle and its lower end, the slider planar body 431 has a tuning fork-shaped opening 439 for a snap-in spring part 433 in the middle of the tuning fork-shaped opening 439 . The snap-in spring part 433 is directed with its nose 4331 in the guide groove 1735 and prevents removal of the slider 43 from the channel in the mounted state (as is shown in FIG. 5 b ).
A thermotransfer ink ribbon cassette with chip is shown in FIG. 9 in perspective view from the rear upper left. The thermotransfer ink ribbon is visible in a lower first opening 88 and in a second opening 85 of the left side wall 83 of the housing of the thermotransfer ink ribbon cassette. The chip 81 (for example a conventional type SEL 4442 from Siemens AG) is centrally mounted near the upper edge of upper cassette wall 82 and the rear cassette wall 84 . The latter has a height H=55 mm and a maximal length L=10.2 mm in the region of the lower first opening 88 up to the upper edge. A circular opening 86 is incorporated into the one half of the rear cassette wall 84 for a winding mandrel (not shown). The other half abuts the left side wall 83 of the housing.
A perspective view from the front left and above of the feed table and of the chassis of the franking machine is shown in FIG. 10 . The perspective view also shows the relative position of mechanical and electrical components for the feed table 4 and for the chassis 40 . These components (such as the locking element 11 with the pressure element 12 , the circuit board 13 with the chip reader unit 14 , the rollers 1792 and 1793 (participating in an un-actuated manner in the ejection), the sensor 36 and the slider 43 ) are all mounted on the shaped cassette bay part shown in FIGS. 5 a and 5 b . The position of the locking element 11 with the pressure element 12 relative to the thermotransfer print head 9 corresponds to the necessary separation resulting from the height H of the cassette 8 . The thermotransfer print head 9 is fastened on the chassis 40 and protrudes into the mail transport path.
The slider 43 is arranged between the chassis 40 and the shaped cassette bay part, upstream (in terms of the mail flow) from the thermotransfer print head 9 . A mechanism is arranged upstream (in terms of the mail flow) from the slider 43 and fastened on the chassis 40 such that it can rotate around a rotation axis 39 . The mechanism has an oblong guide opening 46 introduced into the chassis 40 for the axle 34 , for the encoder wheel 35 and the friction wheel 38 , an encoder wheel mounting 33 that has a nose 3336 for fastening one end of a tension spring (not shown) and a separation element 47 that has a neck 471 with head 472 for fastening to the other end of the tension spring (not shown). The force effect of the tension spring (not shown) effects the support (shown in FIG. 10 ) of the axle 34 on one end in the oblong guide opening 46 . The actuation slope 437 of the slider 43 abuts the axle 34 in order to be able to shift the bolt 34 into the oblong guide opening 46 when the cassette flap 5 is opened. The force effect of the pressure spring (not shown) of the slider is stronger than that of the tension spring and causes (in a manner not shown) the bolt 34 to be positioned at the other end in the oblong guide opening 46 . The pressure spring is tensed upon closing of the cassette flap 5 , in that its finger 53 presses on the top slope 434 (as has already been explained using FIG. 8 b ).
A circular opening 48 in the chassis 40 is provided for a winding mandrel (not shown) that is downstream (in terms of the mail flow) from the thermotransfer print head 9 . At the outlet of the mail path, the feed table 4 exhibits a quadrilateral opening 45 that is provide for an actuated ejection roller 15 that faces the un-actuated rollers 1792 , 1793 of the shaped cassette bay part, these un-actuated rollers 1792 , 1793 also participating in the ejection of the mail pieces.
FIG. 11 shows a perspective view of an encoder wheel mounting from the front and upper left. The first and third rockers 331 and 33 of the encoder wheel mounting 33 exhibit bearing openings 3315 and 3335 for the axle 34 (not shown), via which the encoder wheel 35 (not shown) and the friction wheel 38 (not shown) are rigidly connected with one another. The second and fourth rocker 332 and 334 of the encoder wheel mounting 33 exhibit bearing openings 3325 and 3345 for the rotation axle 39 (shown in a dash-dot manner). One end of the tension spring 37 is connected with an end 3336 of the third rocker 333 of the encoder wheel mounting 33 . A crank disk 3347 is arranged on the end 3346 of the third rocker 334 of the encoder wheel mounting 33 that is facing away from the rotation axle 39 . The first and second rockers 331 and 332 are separated from one another via a connection piece 335 . Connection pieces are likewise integrally molded between the other adjacent rockers. A nose 3317 is integrally molded on the first rocker 331 .
A side view of the feed table and chassis of the franking machine in the state of a closed (not shown) flap is shown in FIG. 12 and a front view is shown in FIG. 13 . The inventive mechanism includes the separation element 47 fastened on the chassis 40 , the oblong opening (not visible) introduced into the chassis 40 and the encoder wheel mounting 33 that can rotate around a rotation axle 39 fastened on the chassis 40 . This encoder wheel mounting 33 actuates a sensor 36 and supports the axle 34 for the encoder wheel 35 and the friction wheel 38 , whereby the position of the axle 34 is changed by the slider 43 due to the elastic force F 1 of a pressure spring 44 counter to the elastic force F 2 of a stressed tension spring 37 between the separation element 47 (fastened on the chassis 40 ) and the encoder wheel mounting 33 as soon as the flap is opened and the force effect F decreases. When a closing of the cassette flap 5 ensues, the pressure spring 44 is tensed since F 2 <F 1 <F. Via the opening 18 , the friction wheel 38 of the shaped cassette bay part then arrives (in the manner shown in FIG. 5 a ) at engagement in the inserted cassette with its thermotransfer ink ribbon.
The axle 34 , the rotation axle 39 , the separation element 47 and the chassis 40 preferably are produced from metal, and the locking element 11 , the tension spring 37 , the pressure spring 44 , the torsion spring 364 preferably are produced from spring steel. The torsion spring 364 exerts a third force effect F 3 on the crank disk 3347 of the spring-mounted encoder wheel mounting 33 via the sensor actuation lever 361 , with F 3 <F 2 .
The encoder wheel mounting 33 can be manufactured from plastic or metal by injection-molding, but the invention is not limited to the shown preferred embodiment.
Alternatively, the encoder wheel mounting 33 , the axle 34 and the axle 39 can exhibit a non-linear shape. For example, they can be curved from a wire segment like a paper clip. A hollow shaft attached on the wire segment instead of the axle 34 then bears the encoder wheel 35 and the friction wheel 38 . The arrangement of the tension and/or pressure springs can be modified or omitted. The sensor actuation element is described above as a spring-supported, rotatable sensor actuation lever 361 , but other embodiments are conceivable as long as they are able to detect a rotation movement. For example, a gearwheel engaged with a further gearwheel arranged on the rotation axle 39 can be arranged on the rotation axle 360 at the sensor 36 . The torsion spring 364 can then be omitted. A further slider can serve as the sensor actuation element in a further embodiment variant.
Although modifications and changes may be suggested by those skilled in the art, it is the intention of the inventor to embody within the patent warranted hereon all changes and modifications as reasonably and properly come within the scope of his contribution to the art.
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A printing mail processing apparatus has an apparatus housing with a cassette bay therein, for removably receiving an exchangeable cassette. The cassette bay is closed by a cassette flap that has a finger on an underside thereof that interacts with a sensor. The sensor can detect, before exchange of a cassette that flap position for which a cassette extraction is possible. A microprocessor is connected to the sensor and uses the signal from the sensor to detect the position of the cassette flap. Given a closed cassette flap, the microprocessor causes voltage to be supplied to a chip reader unit mounted in the cassette bay. Given an opened cassette flap, the microprocessor causes voltage to be disconnected from the chip reader unit before each cassette exchange.
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TECHNICAL FIELD
[0001] The present disclosure relates to engine exhaust aftertreatment systems and more particularly to a pump and tank unit used in providing a reductant to the exhaust aftertreatment systems.
BACKGROUND
[0002] A selective catalytic reduction (SCR) system may be included in an exhaust treatment or aftertreatment system for a power system to remove or reduce nitrous oxide (NOx or NO) emissions coming from the exhaust of an engine. SCR systems use reductants, such as urea, that are introduced into the exhaust stream to significantly reduce the amount of nitrous oxides (NOx) in the exhaust.
[0003] The construction and installation of the SCR system can be a considerable component of the overall power system cost. Packaging of the SCR system is of particular concern given that most applications for power systems have a limited space requirement. That is, there is only so much space available within a machine, boat, generator housing, etc., in which the power system is installed to accommodate the engine and any required emissions solutions systems, such as the SCR system.
[0004] U.S. Pat. No. 7,895,829 (the '829 patent) discloses an aftertreatment system including an SCR system. The SCR system includes a urea solution tank. A urea solution pump is provided within the urea solution tank.
SUMMARY
[0005] The present disclosure provides a fluid supply assembly including a tank configured for holding a fluid, and a pump configured to draw the fluid from the tank, wherein the tank includes a recess and the pump is mounted to the tank in the recess.
[0006] The present disclosure also provides an aftertreatment system that includes an exhaust conduit which transmits exhaust gases from an engine, a fluid supply assembly which introduces a fluid into the exhaust gases. The fluid supply assembly includes a tank configured for holding a fluid, a pump disposed in a recess and configured to draw the fluid from the tank, and an SCR catalyst which receives the exhaust and reductant. The tank includes a recess therein. The pump is supported on two separate sides by the recess and an SCR catalyst which receives the exhaust and reductant.
[0007] The present disclosure also provides a method of manufacturing a fluid supply assembly that includes providing a tank configured to hold the fluid, the tank having a recess, mounting a pump to the tank in the recess, and fluidly connecting the pump to an inside of the tank via a header.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is a diagrammatic view of a machine including a power system with an engine and an aftertreatment system.
[0009] FIG. 2 is a diagrammatic view of the aftertreatment system including a reductant supply system including a pump electronics and tank unit (PETU) according to the present disclosure.
[0010] FIG. 3 is a left-side elevation view of a PETU according to the present disclosure.
[0011] FIG. 4 is a right-side elevation view of a PETU according to the present disclosure.
[0012] FIG. 5 is a top elevation view of a PETU according to the present disclosure.
DETAILED DESCRIPTION
[0013] FIG. 1 is a diagrammatic view of a machine 1 including a cab 2 where an operator 3 sits and a power system 10 . The machine 1 might be a track type tractor (as illustrated), on-highway truck, car, vehicle, off-highway truck, earth moving equipment, material handler, logging machine, compactor, construction equipment, stationary power generator, pump, aerospace application, locomotive application, marine application, or any other device or application requiring a power system 10 .
[0014] The power system 10 includes an engine 12 and an aftertreatment system 14 to treat an exhaust stream 16 produced by the engine 12 . The engine 12 may include other features not shown, such as controllers, fuel systems, air systems, cooling systems, peripheries, drivetrain components, turbochargers, exhaust gas recirculation systems, etc. The engine 12 may be any type of engine (internal combustion, gas, diesel, gaseous fuel, natural gas, propane, etc.), may be of any size, with any number of cylinders, any type of combustion chamber (cylindrical, rotary spark ignition, compression ignition, 4-stroke and 2-stroke, etc.), and in any configuration (“V,” in-line, radial, etc.).
[0015] The aftertreatment system 14 includes an exhaust conduit 18 for delivering the exhaust stream 16 and a Selective Catalytic Reduction (SCR) system 20 . The SCR system 20 includes an SCR catalyst 22 , and a reductant supply assembly 24 .
[0016] In some embodiments, the aftertreatment system 14 may also include a diesel oxidation catalyst (DOC) 26 , a diesel particulate filter (DPF) 28 , and a clean-up catalyst 30 . The DOC 26 , DPF 28 , SCR catalyst 22 , and clean-up catalyst 30 may include the appropriate catalyst or other material, respective of their intended functions, disposed on a substrate. The substrate may consist of cordierite, silicon carbide, other ceramic, a metal structure or other configurations of similar materials. In one embodiment, the substrates may form a honeycomb structure with a plurality of longitudinal channels or cells for the exhaust stream 16 to pass through. The DOC 26 , DPF 28 , SCR catalyst 22 , and clean-up catalyst 30 substrates may be housed in canisters, as shown, or may be integrated into the exhaust conduit 18 . The DOC 26 and DPF 28 may be in the same canister, as shown, or may be separately disposed. Similarly, the SCR catalyst 22 and clean-up catalyst 30 may also be in the same canister, as shown, or may be separately disposed.
[0017] The aftertreatment system 14 is configured to remove, collect, or convert undesired constituents from the exhaust stream 16 . The DOC 26 oxidizes carbon monoxide (CO) and unburnt hydrocarbons (HC) into carbon dioxide (CO2) and water (H2O). The DPF 28 collects particulate matter or soot. The SCR catalyst 22 is configured to reduce an amount of nitrous oxides (NOx) in the exhaust stream 16 in the presence of a reductant.
[0018] The clean-up catalyst 30 may embody an ammonia oxidation catalyst (AMOX). The clean-up catalyst 30 is configured to capture, store, oxidize, reduce, and/or convert reductant that may slip past or breakthrough the SCR catalyst 22 . The clean-up catalyst 30 may also be configured to capture, store, oxidize, reduce, and/or convert other constituents present in the exhaust stream.
[0019] In the illustrated embodiment, the exhaust stream 16 is configured to exit the engine 12 , pass through the DOC 26 and DPF 28 , pass through the SCR catalyst 22 , and then pass through the clean-up catalyst 30 via the exhaust conduit 18 . In the illustrated exemplary embodiment, the SCR system 20 is downstream of the DPF 28 and the DOC 26 is upstream of the DPF 28 . In embodiments where it is included, the clean-up catalyst 30 is downstream of the SCR system 20 . In other embodiments, these devices may be arranged in a variety of orders and may be combined together. In one alternative embodiment, the SCR catalyst 22 may be combined with the DPF 28 with the catalyst material for the SCR deposited on the DPF 28 . Other exhaust treatment devices may also be located upstream, downstream, or within the SCR system 20 .
[0020] FIG. 2 is a diagrammatic view of the aftertreatment system 14 wherein the reductant supply assembly 24 is configured to introduce the reductant into the exhaust stream 16 upstream of the SCR catalyst 22 . The reductant supply assembly 24 may include a reductant supply system 32 , which may also be referred to hereinafter as a pump electronics and tank unit (PETU) 32 , a reductant line 34 , and an injector 36 . In the embodiment illustrated in FIGS. 1 and 2 , the PETU 32 generally includes a tank 110 , a header 120 , a pump 130 and associated electronics 140 . Embodiments of the PETU 32 will be described in more detail below.
[0021] As illustrated in FIGS. 2-5 , the tank 110 may include a cap and associated filling passage 111 to introduce reductant into the tank 110 . The tank 110 also includes a recess 112 . The recess 112 is configured such that the pump 130 is at least partially disposed within the recess 112 . Referring in particular to FIGS. 3-5 , in at least one embodiment, the tank 110 includes grooves 113 disposed along the tank 110 to provide structural strength thereto. The tank 110 may also be configured to include at least one drain 114 disposed along the bottom thereof in order to easily drain the tank 110 , e.g., to drain the tank 110 to remove sludge, to prevent freezing of the reductant within the tank, or to correct a misfilling event.
[0022] As illustrated in FIGS. 2-5 , the header 120 includes a plurality of ports disposed thereon. According to one exemplary embodiment, the header 120 includes a reductant outlet port 121 , a reductant return port 122 for returning reductant to the tank 110 during a purge event, a coolant inlet port 123 and a coolant outlet port 124 . In the illustrated embodiment, the header 120 also includes an electrical connection 125 which may be connected to a level sensor (not shown), a temperature sensor (not shown), or various other sensors for detecting conditions within the tank 110 . As illustrated in FIG. 2 , the header 120 may be connected to a coolant loop 126 . The function of the coolant will be described in more detail below. The header 120 may also be connected to a reductant pickup line 127 which extends in proximity to a bottom of the tank 110 . Alternative embodiments include configurations wherein one or more of the ports, lines, sensors and/or connections described above may be omitted or wherein additional ports, lines, sensors and/or connections may be added.
[0023] As illustrated in FIGS. 2-5 , the pump 130 may be connected to the various ports on the header 120 . For instance, a reductant supply line 151 may connect the reductant outlet port 121 to a reductant inlet 131 on the pump 130 . Similarly, a reductant return line 152 may connect the reductant return port 122 to a reductant outlet 132 on the pump 130 . The pump 130 may also include various connections for coolant. In the illustrated embodiment, the pump 130 includes a coolant inlet 134 connected to a coolant supply line 154 in fluid communication with the coolant outlet port 124 on the tank 110 . In such an embodiment, the pump 130 receives coolant that has already flowed through the tank 120 . The pump 130 may include an internal passage (not shown) in fluid communication with the pump coolant inlet, wherein the internal passage is in thermal communication with a chamber of the pump which contains reductant. Thus, the internal passage of the pump 130 may be heated such that any reductant contained in the pump 130 may be thawed by the coolant. In the illustrated embodiment, the pump 130 includes a coolant outlet 135 for flowing coolant back to the engine 12 . However, such a configuration is only one exemplary embodiment, and alternative configurations are within the scope of this disclosure.
[0024] As illustrated in FIGS. 2-5 , the pump 130 is disposed at least partially within the recess 112 of the tank 110 . That is, the pump 130 is mounted such that it is bounded on two sides, e.g., a horizontal and vertical side, by edges of the recess 112 . In one embodiment, the pump 130 is mounted to the tank 110 via at least one fastener assembly 136 . In one exemplary embodiment the fastener assembly 136 may include a boss and a means for securing the pump 130 to the boss. According to one exemplary embodiment, the fastener assembly 136 may be spun-welded to the tank 110 , thus reducing a number of through holes in the tank 110 . A support structure of the pump 130 then connects to the fastener assembly 136 . In the present exemplary embodiment, the pump 130 is illustrated as being directly connected to the at least one fastener assembly 136 , and thus the pump 130 is mounted directly to the tank 110 via the fastener assembly 136 . Alternative embodiments include configurations wherein the pump 130 may be disposed on a bracket (not shown) which is mounted to the fastener assembly 136 , and thus the bracket may be the support structure of the pump 130 .
[0025] The pump 130 may further include a filter 137 . The filter 137 may be disposed such that it may be easily removed from the pump 130 in a substantially downward direction parallel with a height of the tank 110 . According to various alternative embodiments, the filter 137 may be disposed separately from the pump in a separate housing; however, even in such an alternative embodiment, the filter 137 is in fluid communication with the pump 130 .
[0026] A coolant flow valve 138 may be connected to the pump 130 or, in an alternative embodiment, on a bracket (not shown) coupled to the tank 110 , e.g., the bracket (not shown) on which the pump 130 may alternatively be mounted. The coolant flow valve 138 may control a flow of coolant from the engine 12 to the tank 110 through a coolant inlet line 153 . In at least one embodiment, the coolant flow valve 138 includes an electronic control capability as discussed below.
[0027] As illustrated in FIGS. 2-5 , the electronics unit 140 may be disposed adjacent to the pump 130 . In one embodiment, the electronics unit 140 may be mounted directly to the pump 130 , although alternative embodiments include configurations wherein the electronics unit 140 is connected to the bracket (not shown) on which the pump 130 is mounted for connection to the tank 110 . According to one exemplary embodiment, the electronics unit 140 supplies control signals to the pump 130 , injector 36 and coolant flow valve 138 . In the present embodiment, the electronics unit 140 receives signals from a level sensor (not shown) and a temperature sensor (not shown) from the tank 110 and relays those signals to an independent electronics unit (not shown), such as an electronics control unit associated with the main power system 10 . The electronics unit 140 may also receive signals from at least one NOx sensor 160 and relay signals from that at least one NOx sensor 160 to the independent electronics unit. The electronics unit 140 , or the independent electronics unit, may use the NOx sensor 160 , or engine maps, or both to control the introduction of reductant from the reductant supply system 24 to achieve the desired level of NOx reduction while controlling reductant slip through the clean-up catalyst 30 .
[0028] Alternative embodiments include configurations wherein the electronics unit 140 is omitted from the PETU 32 and disposed in an alternative location, e.g., separate from the tank 110 , header 120 and pump 130 . According to one exemplary embodiment, the electronics unit 140 is omitted altogether; in such an alternative embodiment, electronic control signals may alternatively be sent from, and received by, the independent electronics unit. In such an alternative exemplary embodiment, signals from the level sensor (not shown), the temperature sensor (not shown), soot sensors (not shown) and NOx sensor 160 may be sent directly to the independent electronics unit. Combinations of the two configurations are also possible within the scope of this disclosure.
[0029] As shown in FIGS. 3 and 5 , the PETU 32 has a height h 1 , a length h 1 and a width w 1 . The tank 110 has a height h 2 , a length l 2 and a width w 2 . The pump 130 has a height h 3 , a length l 3 and a width w 3 . As particularly shown in FIG. 5 , the pump 130 is disposed such that a width of the header 120 , pump 130 and the electronics unit 140 is substantially equal to the width w 1 of the tank 110 . Also, as shown in FIGS. 3-5 , the height h 1 of the PETU 32 is less than a combined height of the tank 110 and the pump 130 (h 1 <h 2 +h 3 ); a length l 1 of the PETU is less than a combined length of the tank 110 and pump 130 (l 1 <l 2 +l 3 ). As shown in FIG. 3 , the height direction corresponds to a gravitation field direction, e.g., the height of the tank 110 is the direction in which fluid fills the tank 110 . Advantages of such a configuration are discussed in detail below.
[0030] The injector 36 injects reductant in a mixing section 40 of the exhaust conduit 18 where the reductant may be mixed with the exhaust stream 16 . A mixer (not shown) may also be included in the mixing section 40 to assist the mixing of reductant with the exhaust stream 16 . While other reductants are possible, urea is the most common reductant.
[0031] A heat source (not shown) may also be included to remove soot from the DPF 28 in a process referred to as regeneration. The heat source may also thermally manage the SCR catalyst 22 , DOC 26 , or clean-up catalyst 30 , to remove sulfur from the DOC 26 , DPF 28 , SCR catalyst 22 or clean-up catalyst 30 , or to remove deposits of reductant that may have formed in any of those components or along the exhaust conduit 18 . The heat source may embody a burner, hydrocarbon dosing system to create an exothermic reaction on the DOC 26 , electric heating element, microwave device, or other heat source. The heat could also be applied by operating the engine 12 under conditions to generate elevated exhaust stream 16 temperatures. A backpressure valve or another restriction in the exhaust conduit 18 could also be used to cause elevated exhaust stream 16 temperatures.
INDUSTRIAL APPLICABILITY
[0032] Prior art SCR systems utilize reductant supply systems that locate the tank separately a distance away from the pump. The pump and tank are then connected via relatively long lines for transporting the reductant from one to another. This leads to increased risk of line freezing due to failure to remove all reductant from the lines when the machine is shut down. Such a configuration also leads to difficulties with packaging as separate spaces must be found for the pump and tank. The tanks used in the prior art SCR systems also are typically of a size and shape such that even if a pump were to be mounted to the tank, such a combined unit would have at least one dimension that was equal to the sum of the extension of the pump in that dimension and the extension of the tank in that dimension, e.g., the combined height would be equal to the height of the pump plus the height of the tank. Such a configuration also leads to difficulties with packaging. The present disclosure is presented to alleviate such difficulties.
[0033] Referring again to FIGS. 1 and 2 , in operation, the power system 10 generates the exhaust stream 16 . The exhaust stream flows along the exhaust conduit 18 and is received by the DOC 26 , when included, and the DPF 28 . The DOC 26 and DPF 28 modify the exhaust stream 16 to remove particulate matter and oxidizes carbon monoxide (CO) and unburnt hydrocarbons (HC) into carbon dioxide (CO2) and water (H2O) as discussed above.
[0034] The modified exhaust stream 16 then flows downstream to be treated by the SCR system 20 . The injector 36 injects a reductant into the exhaust stream 18 upstream of the SCR catalyst 22 . While other reductants are possible, urea is the most common reductant. The urea reductant converts, decomposes, or hydrolyzes into ammonia (NH3) and is then adsorbed or otherwise stored in the SCR catalyst 22 . The NH3 is then consumed in the SCR catalyst 22 through a reduction of NOx into nitrogen gas (N2) and water (H2O).
[0035] The injector 36 receives the reductant from the pump 130 , which in turn draws the reductant from the header 120 and the tank 110 along the reductant pickup line 127 . The reductant may undergo filtering within the tank 110 , at the filter 137 and again at the injector 36 , among various other filtering locations. According to various alternative embodiments, the filter 137 may be easily removed from along an overhanging portion of the pump 130 rather than necessitating a removal of the pump 130 from its mounting position in order to access the filter 137 .
[0036] As illustrated in FIGS. 2-5 , the PETU 32 includes the tank 110 having sufficient capacity for supplying reductant to the exhaust stream 16 during operation of the power system 10 . That is, if the power system 10 typically undergoes a work period of 8 hours between shut-down events, the tank 110 may be sized to provide enough reductant for operation of the power system 10 under typical operating conditions during the 8 hour work period.
[0037] As briefly discussed above, the PETU 32 includes a thermal management system utilizing coolant from the engine 12 in order to thaw, or prevent freezing of, the reductant within the tank 110 , header 120 and pump 130 . In operation, a temperature reading sensed by the temperature sensor in the tank may be sent to the electronics unit 140 . A determination about the condition of the reductant contained in the tank 110 may then be made based on the temperature reading and appropriate actions may be taken based on the determination, e.g., if the temperature reading is below a predetermined threshold, the electronics unit 140 initiates a reductant thawing event.
[0038] One embodiment of the thawing event may include opening the coolant flow valve 138 to allow coolant from the engine, which has a relatively high temperature compared to the frozen reductant, to flow therethrough, into the header 120 and then through the coolant loop 126 of the tank 110 . After flowing through the radiative coolant loop, the coolant then flows back out through the header 120 and into the pump 130 . The coolant then transfers thermal energy to the pump 130 before flowing back to the engine 12 . Once the temperature reading from the tank 110 is above the predetermined threshold, the electronics unit 140 determines the reductant to be thawed and terminates the thawing event, e.g., by closing the coolant flow valve 138 .
[0039] According to various alternative embodiments, the reductant lines 34 may be heated by electrical heaters (not shown) or by water jackets (not shown) heated by engine coolant in order to thaw, or prevent freezing of, reductant contained therein.
[0040] While one embodiment of a method for thawing the tank 110 , header 120 and pump 130 has been described above, the present disclosure is not limited thereto and various other control schemes may alternatively be used to thermally manage the SCR system 20 .
[0041] By locating the tank 110 and pump 130 adjacent to one another with the pump 130 disposed within a recess 112 of the tank 110 , the coolant flow lines, i.e., the coolant inlet line 153 and coolant supply line 154 , from the coolant control valve 138 to the header 120 and from the header 120 to the pump 130 , may be shortened, thereby reducing the overall number of coolant connections as compared to a system where the pump and tank are separately supplied with coolant.
[0042] In contrast to prior art systems wherein the tank 110 and pump 130 are separately mounted, the disclosed system allows for easier packaging and assembly. That is, in the disclosed system, all of the connections related to the reductant supply system 24 are conveniently located in one assembly. The required connections between the tank 110 , header 120 , pump 130 and electronics unit 140 may be preassembled prior to insertion into a particular application, e.g., a machine.
[0043] The disposition of the pump 130 within the recess 112 provides mounting options for providing both vertical and lateral support to the pump 130 in relation to the tank 110 . Using two planes of support may be advantageous in a high-vibration environment, such as those produced in association with power system 10 . As illustrated in FIGS. 2-5 , having multiple planes of support may reduce movement of the pump 130 along a single plane and provides additional support in the event of a fastener assembly 136 failure. However, the recess 112 also provides easy mounting options if the pump 130 were to be mounted to only one side of the recess 112 , e.g., the pump 130 may be mounted only to the side of recess 112 or only to the bottom of recess 112 depending upon a desired assembly process.
[0044] In one embodiment, the fastener assemblies 136 may be spin-welded to the tank 110 , thereby supplying a quick and inexpensive method for providing the fastener assemblies 136 on the tank 110 . In addition, such a method reduces the number of orifices in the tank and thereby helps to prevent opportunities for leakage from the tank 110 . Such a method also may reduce the total number of parts used in the system, and thus reduces the number of potential failure modes.
[0045] Although the embodiments of this disclosure as described herein may be incorporated without departing from the scope of the following claims, it will be apparent to those skilled in the art that various modifications and variations can be made. Other embodiments will be apparent to those skilled in the art from consideration of the specification and practice of the disclosure. It is intended that the specification and examples be considered as exemplary only, with a true scope being indicated by the following claims and their equivalents.
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A fluid supply assembly includes a tank configured for holding a fluid and a pump configured to draw the fluid from the tank, wherein the tank includes a recess and the pump is mounted to the tank in the recess. The pump may be connected to the tank along either, or both of, a first and/or a second surface of the recess, wherein the first surface and the second surface may be orthogonal to one another. The fluid supply assembly may further include a header disposed on a horizontal surface of the tank, the header may include at least a portion thereof which extends into an interior of the tank, wherein the pump may draw the fluid from the tank via the header.
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BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] This invention relates generally to submersible tools and, more specifically, to a Spa and Pool Step Vacuum.
[0003] 2. Description of Related Art
[0004] Swimming pool and hot tubs (“spas”) need periodic cleaning to remove debris that either grows or falls into the pool or spa. When cleaning a pool, it is conventional to use a vacuum cleaning device that gets its suction from the pool's permanent filtration system. These “non-portable” vacuum cleaners will generally have a flexible hose that connects to one of the filter intake ports at the side of the pool. Items vacuumed up by the non-portable vacuum cleaners are taken out of the pool and into the main pool filter bank. The non-portable pool vacuum is very suitable for cleaning large, substantially flat and smooth expanses in the pool.
[0005] When smaller, more intricate areas, such as spas or pool steps, need cleaning, the non-portable pool vacuum is not very effective. In response, a variety of manual and electric “portable” pool vacuums have been introduced. Portable pool vacuums are typically smaller than the non-portable types, and they further do not require a long hose connected to the pool or spa's filtration system. One version of a portable pool vacuum is depicted below in FIG. 1 .
[0006] FIG. 1 is a side view of the prior art pool vacuum apparatus 10 of Goertzen, III et al., U.S. Pat. No. 3,755,843. The Goertzen portable pool vacuum 10 has an onboard pump 26 that sucks water through the head 14 and hose 24 , and then filters out any entrained debris in an encapsulated filtration unit 16 . The pump 26 obtains its electrical power from an external battery 30 , via a waterproof cable 32 .
[0007] While the Goertzen apparatus 10 appears to be more maneuverable than a non-portable vacuum, it still has more than one problem related to it. First, the head 14 includes a pair of fairly large wheels, and is therefore fairly unwieldy to move around. Next, the battery 30 power supply is not incorporated within the device 10 ; as a result, the user has to manage the cable 32 and the cell 30 . Further, the filter unit 16 is a specialized filter cartridge that is typically limited in availability and expensive. Finally, placing the pump 26 at the upper end of the apparatus 10 does not assist the user in forcing the vacuum against the bottom—placement at or near the bottom of the vacuum 10 (i.e. near the head 14 ) would be more advantageous. A portable pool vacuum is needed that solves at least these problems with the Goetzen vacuum 10 . FIG. 2 depicts another prior pool vacuum.
[0008] FIG. 2 is a side view of the prior art pool vacuum cleaner 1 of Schuman, U.S. Pat. No. 4,962,559. The Schuman vacuum cleaner 1 has a brush head 2 which is defined by an integrated hose/pipe through its center. The pipe/hose leads to a filter housing 25 for retaining a pleated filter element. After being filtered, incoming water flows out through a gap formed between the filter housing 25 and the adjacent motor housing 39 . Adjacent to the motor housing is the battery housing 53 , which transitions into the handle 57 that is held onto by the user.
[0009] The Schuman device also has deficiencies. First, the battery housing 53 is located in a submerged portion of the device 1 —this adds substantial weight to the device in a place that will interfere with easy movement around the pool, and will further make battery change-out more difficult the vacuum 1 in the vicinity of the battery housing 53 must be completely dry before, during and after any battery maintenance is done. Furthermore, like Goertzen device, the Schuman vacuum uses a filter housing having a filter cartridge. The large size of Schuman also prevents the convenient cleaning of intricate areas. What is needed is a portable pool vacuum that solves these problems.
SUMMARY OF THE INVENTION
[0010] In light of the aforementioned problems associated with the prior devices, it is an object of the present invention to provide a Spa and Pool Step Vacuum. The vacuum device should incorporate a submersible pump for maximum utility. The device should be lightweight and portable and not require a hardwired electrical supply. The device should further include a removable external filter sack or bag to provide maximum filtration capacity with the minimum of weight and drag. The vacuum should further provide a tapered nozzle having a roller to create the desired air gap between the tip of the nozzle and the surface being cleaned.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The objects and features of the present invention, which are believed to be novel, are set forth with particularity in the appended claims. The present invention, both as to its organization and manner of operation, together with further objects and advantages, may best be understood by reference to the following description, taken in connection with the accompanying drawings, of which:
[0012] FIG. 1 is a side view of the prior art pool vacuum apparatus of Goertzen;
[0013] FIG. 2 is a side view of the prior art pool vacuum cleaner of Schuman;
[0014] FIG. 3 is perspective view of the spa and pool step vacuum of the present invention;
[0015] FIG. 4 is a partially exploded perspective view of the vacuum of FIG. 3 ;
[0016] FIG. 5 is a partial cutaway side view of the vacuum of FIGS. 3 and 4 ; and
[0017] FIG. 6 is an exploded perspective view of the head assembly of the vacuum of FIGS. 3-5 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0018] The following description is provided to enable any person skilled in the art to make and use the invention and sets forth the best modes contemplated by the inventor of carrying out his invention. Various modifications, however, will remain readily apparent to those skilled in the art, since the generic principles of the present invention have been defined herein specifically to provide a Spa and Pool Step Vacuum.
[0019] The present invention can best be understood by initial consideration of FIG. 3 . FIG. 3 is perspective view of the spa and pool step vacuum 11 of the present invention. The vacuum 11 comprises an elongated handle assembly 13 , a head assembly 15 extending from the handle assembly 13 , and a filter bag 17 attached to the head assembly 15 . All of the submersible components are waterproof and suitable for submersing in water, and particularly in water having the chemical composition of a typical pool or hot tub/spa. If we now turn to FIG. 4 , we can examine the present invention in more detail.
[0020] FIG. 4 is a partially exploded perspective view of the vacuum 11 of FIG. 3 . The head assembly 15 comprises a motor/pump assembly 18 , from which extends a nozzle 20 and a socket member 22 . The socket member 22 is configured to accept an end of the handle assembly 13 therewithin, and more specifically, the extension member 25 element of the handle assembly 13 . The extension member 25 is accepted within a coupling 28 at its other end; the coupling 28 also forms one end of the battery compartment 27 . While the extension member 25 is detachable from the coupling 28 for storage, the coupling 28 is sealed to the battery compartment 27 . At the other end of the battery compartment 27 is attached the control module 30 . The control module 30 is sealed to the battery compartment 27 , and provides a switch 34 for turning the device on and off. The control module 30 also has a battery access cap 32 , which threadedly engages the head 30 to seal the interior of the compartment 27 against water intrusion. Still further, the head 30 has a power supply jack 36 for plugging in a DC power source for recharging the batteries within the battery compartment 27 . Proceeding to FIG. 5 , we can delve deeper into the features of this invention.
[0021] FIG. 5 is a partial cutaway side view of the vacuum 11 of FIGS. 3 and 4 . In this embodiment, the rechargeable or nonrechargable batteries 38 are retained within the otherwise hollow extension member 25 . The coupling 28 provides the interconnection between the battery compartment 27 and the extension member 25 . The coupling 28 further provides electrical connection between the batteries 38 and the extension member 25 (for use in the head assembly 15 ).
[0022] The extension member 25 is essentially hollow except for the electrical leads running down its length from the battery compartment 27 to the head assembly 15 . The head assembly 15 houses the battery-powered motor 49 which drives the pump impeller 46 to create water flow in through the mouth 42 and throat 40 of the head assembly 15 .
[0023] Of particular note in this design are two features: the mouth 42 is at an angle to the axis defined by the extension member 25 in order to make it easier to place the opening of the mouth 42 flat or nearly flat against the surface being vacuumed. Second, the mouth 42 has a roller 44 extending slightly out from the throat 40 through the mouth 42 . The roller 44 provides the user with a place to rest the device while vacuuming, while also creating slight standoff or gap between the mouth 42 and the surface being vacuumed so that larger items can be sucked into the mouth 42 even while resting or rolling on the roller 44 . The gap created by the roller 44 also provides supplemental water flow into the throat 40 to assist in carrying debris through the pump and out through the discharge stem 48 . The filter bag (see FIG. 3 ) is attachable to the discharge stem 48 to capture debris exiting the head assembly 15 . Allowing the filter bag (see FIG. 3 ) to be attached to the exterior of the device 11 reduces the weight of the device 11 , and also makes filter changes and cleanings very simple. Furthermore, bag material is inherently less expensive than a pleated filter cartridge.
[0024] In another non-depicted embodiment, the batteries 38 will be external to the device 11 . In this embodiment, the control module 30 will include a socket for accepting a conventional solid state battery pack, such as those now commonly used for power drills or saws. When recharging of the battery pack of this second type of vacuum is needed, it is a simple matter to release it from the end of the control module 30 , and then drop it into the charging base station (that came with the power tool). Finally turning to FIG. 6 , we can review the elements of the head assembly 14 .
[0025] FIG. 6 is an exploded perspective view of the head assembly 14 of the vacuum 11 of FIGS. 3-5 . The roller 44 has an elongate ovoid shape and is further defined by a pair of pegs 60 , one each extending from the two ends. The pegs 60 cooperate with a corresponding pair of apertures 61 adjacent to the sides of the mouth 42 . When the pegs 60 are snapped into place in the apertures 61 , the roller 44 will be held firmly, while still being free to rotate (roll) around the axis formed by the pegs 60 .
[0026] The nozzle 20 is defined by the mouth 42 at its leading end, and then transitions into the bell 56 . The bell 56 is formed with a plurality of tabs 58 extending outwardly therefrom to engage the collar 52 formed in the housing 50 , thereby by securely attaching the bell 56 to the housing 50 .
[0027] Within the housing 50 is further found the motor 49 (within a waterproof container), to which the pump impeller 46 is attached. When the motor 49 is supplied with electrical power, its shaft will rotate and will drive the pump impeller 46 also to rotate. Rotation of the pump impeller 46 will create a suction within the bell 56 , which will draw water and debris into the nozzle 20 and out through the discharge stem 48 . As gasket 54 is held between the housing 50 and the bell 56 in order to prevent water leaking in through the point of connection between the two. The housing 50 then attaches to the extension member (see previous figures) via the socket member 22 .
[0028] Those skilled in the art will appreciate that various adaptations and modifications of the just-described preferred embodiment can be configured without departing from the scope and spirit of the invention. Therefore, it is to be understood that, within the scope of the appended claims, the invention may be practiced other than as specifically described herein.
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A Spa and Pool Step Vacuum is disclosed. The vacuum device incorporates a submersible pump. The device is lightweight and portable and does not require a hardwired electrical supply. The device further includes a removable external filter sack or bag to provide maximum filtration capacity with the minimum of weight and drag. The vacuum further provides a tapered nozzle having a roller to create the desired air gap between the tip of the nozzle and the surface being cleaned.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an infeed station of a stack palletizing system, with a stack feeder, a first and second chamber, which can each receive stacks from the stack feeder, first conveying means assigned to the first chamber and second conveying means assigned to the second chamber, with which stacks are conveyed in the chambers and can be transferred to a stack gripper, and first centering means for centering the stacks in the first chamber and second centering means for centering the stacks in the second chamber.
2. Description of the Related Art
A prior-art infeed station of this type is disclosed by EP 1 801 047 A. In the cited document, the station is referred to as a transfer unit and has a displacement unit, on which a carriage is mounted in such a way that it can be displaced horizontally and transversely to the direction of conveyance. Two placement means are provided. They are arranged side by side and support one stack each. In the present case, these placement means are conveyor belts. Two stacks located on the two placement means of the infeed station (or transfer unit, as it is referred to in the cited document) are seized with a stack gripper and set down on a pallet. To process stacks that are relatively wide, the infeed station must be constructed correspondingly wide, but this is a disadvantage with respect to the amount of space that it requires and with respect to the manufacturing costs. Adaptation to different formats is thus possible only with a comparatively wide infeed station.
SUMMARY OF THE INVENTION
The object of the invention is to create an infeed station of the type described above, with which stacks of greatly varying width can be transferred to a stack gripper but which nevertheless can be constructed relatively narrow.
In accordance with the invention this problem is solved by the fact that third conveying means are arranged between the first and second conveying means and that the first and second centering means can be shifted relative to each other in such a way that the third conveying means are positioned in the first or second chamber, and the chamber with the third conveying means is much wider than the other chamber.
The infeed station of the invention provides the option of double infeed or single infeed of stacks. In the case of double infeed, two relatively narrow stacks are received parallel to each other and successively in time and are simultaneously transferred to the gripper. In the case of single infeed, only one relatively wide stack at a time is received and transferred to the gripper. Accordingly, the gripper then palletizes only this relatively wide stack. In the case of single infeed, the stacks are conveyed by the first or the second conveying means and the third conveying means. In the case of double infeed, the conveyance in the first chamber is preferably carried out with the first conveying means and in the second chamber with the second conveying means. The third conveying means is preferably not active here. The infeed station thus allows the processing of relatively narrow stacks as well as much wider stacks and thus has the advantage that it is highly versatile with respect to the stack formats it can handle.
In a further development of the invention, the first and second centering means have two centering members each, which are spaced some distance apart and are supported at an upper end or at a lower end in such a way that they can be shifted transversely to the direction of conveyance of the conveying means. By shifting these centering members, which are preferably designed as centering plates, chambers of highly variable width can be formed. In particular, an asymmetrical arrangement is possible. For double infeed, the two chambers can be adjusted, for example, by shifting the centering members, to a width on the order of, for example, 100-300 mm. For single infeed, a chamber with a width of, for example, 100-500 mm is possible. Preferably, the centering members or centering plates are shifted by a motor, for example, by means of a spindle.
In a further development of the invention, the two chambers and the conveying means and centering means are installed on a table that can be moved transversely to the direction of conveyance, so that the stacks are fed to the first and second chamber by the stack feeder. In the case of double infeed, for example, a first stack is thus fed to the first chamber, and then the table is moved, so that a second stack can be fed to the second chamber. In the case of single infeed, the table is moved in such a way that the correspondingly wide stack is fed to the chamber provided for it.
In a further development of the invention, the centering means can be adjusted independently of one another. This allows a very fast and simple changeover between single infeed and double infeed without the use of tools. The centering means preferably are each supported at an upper end in such a way that they can be displaced on horizontal guide rods.
In a further development of the invention, the conveying means each have rollers. The stacks can be conveyed and centered especially easily and reliably on these rollers. In this connection, it is preferably provided that each of the centering means has a contour at its lower end that is designed to correspond to the contour of the rollers. The centering means thus mesh with the spaces between the rollers and allow especially reliable centering of the stacks.
The invention also concerns a method for transferring stacks to a stack gripper with an infeed station.
The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of the disclosure. For a better understanding of the invention, its operating advantages, specific objects attained by its use, reference should be had to the drawing and descriptive matter in which there are illustrated and described preferred embodiments of the invention.
BRIEF DESCRIPTION OF THE DRAWING
In the Drawing:
FIG. 1 is a schematic perspective view of a stack palletizing system with an infeed station of the invention.
FIG. 2 is a perspective view of the infeed station.
FIG. 3 is another perspective view of the infeed station of the invention.
FIGS. 4 to 7 are top views of the infeed station of the invention, showing the infeed station in different phases of the changeover to a single infeed.
FIG. 8 is a perspective view of the infeed station of the invention, which is set for a single infeed.
FIG. 9 is a side view of a stack gripper.
FIG. 10 is a perspective view of a pallet with palletized stacks.
DETAILED DESCRIPTION OF THE INVENTION
Stacks 15 and 15 ′ can be palletized on a pallet 11 , as shown in FIG. 10 , with the palletizing system 1 shown in FIG. 1 . Cardboard separators 45 are arranged between the stacks 15 and 15 ′. The palletization itself is performed automatically and is controlled in such a way that the stacks 15 and 15 ′ are set down on the pallet 11 optimally and exactly. The cardboard separators 45 are also set down automatically. The stacks 15 and 15 ′ are any type of stacked products, preferably printed products, such as signatures, newspapers, books and the like. The stacks 15 and 15 ′ can be wrapped in sheets or bound in any other way, but this is not necessary. The stacks 15 and 15 ′ can also consist of individual printed products, for example, thick catalogues.
The palletizing system 1 consists of a machine frame 2 , in front of which a stack feeder 3 is arranged, as shown in FIG. 1 . The stack feeder 3 serves to feed the stacks 15 and 15 ′ to a stack infeed station 4 , which is installed inside the frame 2 . The stacks 15 and 15 ′ are conveyed one after another in a row, and for this purpose the stack feeder 3 is provided, for example, with a conveyor belt 3 a . In FIG. 1 , the arrow 46 shows the direction in which the stacks 15 and 15 ′ are fed to the stack infeed station 4 . The stack feeder 3 can be designed in basically any desired way.
The palletizing system 1 also has a stack gripper 5 , which is shown in detail in FIG. 9 . The stack gripper 5 removes stacks 15 from the stack infeed station 4 and sets them down on the pallet 11 . To grip at least one stack 15 , the stack gripper 5 has a finger 38 and a ram 39 as well as a stop element 40 , on which the stack 15 can be positioned. The finger 38 is mounted on an arm 41 , which can be moved by means of an actuating cylinder 44 . The stack 15 consists here of a plurality of printed products 37 . In addition, the stack gripper 5 has a cardboard separator gripper 43 with suction devices 6 . The cardboard separator gripper 43 removes cardboard separators 45 from a cardboard separator magazine 10 and sets them down on the pallet 11 . To control the individual movements, the stack gripper 5 has a suitable control unit 42 . The stack gripper 5 can be moved in all directions in space and along a vertical upright 7 . The upright 7 is supported on a bridge 8 , which can be moved on two horizontal crossbeams 9 spaced some distance apart ( FIG. 1 ).
Finally, the palletizing system 1 has a pallet dispenser 12 and a pallet magazine 14 . By means which in themselves are already well known, the pallets 11 can be removed from the pallet magazine 14 one at a time and dispensed for palletization of the product. After the stacks 15 and 15 ′ have been palletized on the pallets 11 , the pallets can be moved out by a runout conveyor 13 and, for example, loaded onto a vehicle. The pallet 11 can also be loaded only with stacks 15 or only with stacks 15 ′.
As shown in FIG. 2 , the stack infeed station 4 has a table 18 , which is mounted by means of rollers 19 on two parallel tracks 20 . As shown in FIG. 3 , first conveying means 31 , second conveying means 32 , and third conveying means 33 are installed on the table 18 . These conveying means 31 - 33 are, for example, endless conveyors, with, for example, a belt or a chain with drivers. The conveying means 31 - 33 can also each have more than one conveying member, for example, two or more than two endless belt conveyors or chain conveyors.
The table 18 and thus the stack infeed station 4 are arranged in such a way that they can be moved transversely to the direction of conveyance of the conveying means 31 - 33 . The table 18 is moved under automatic control by means of a drive (not shown). In this regard, the table 18 can be shifted in such a way that the stacks 15 can be optionally fed to a first chamber A or a second chamber B of the stack infeed station 4 . In FIG. 2 , the table 18 is positioned in such a way that the stacks 15 are fed to the second chamber B. If the table 18 in FIG. 2 is shifted to the left, a position can be reached in which the stacks 15 are fed to the first chamber A.
In addition, rollers 34 and 35 are arranged on the table 18 as supports. These rollers extend transversely to the direction of conveyance and allow very slip-free conveyance of the stacks 15 and 15 ′. In FIG. 3 , a stack 15 is present in the chamber B. As the drawing shows, the stack 15 is supported on the rollers 34 . The second conveying means 32 is in contact with the stack 15 and is thus able to convey it. A stack 15 that is the same or similar can be similarly conveyed in the chamber A. To assist the conveyance of the stacks, the rollers 34 and 35 can also be designed to be driven.
The first chamber A is laterally bounded by first centering means C, which comprise a first centering member 27 and a second centering member 28 . The second chamber B is laterally bounded by second centering means D, which comprise a third centering member 29 and a fourth centering member 30 . These centering members 27 - 30 extend vertically and parallel to one another. They are designed, for example, as plates. The centering members 27 - 30 are each displaceably supported at an upper end with beams 22 - 25 on guide rods or other suitable guide means. These guide rods 21 are mounted on a supporting frame 16 , which is mounted on the table 18 and extends upward. The purpose of the centering members 27 - 30 is to center the stacks 15 and 15 ′ during their conveyance in chambers A and B. To this end, the centering members 27 - 30 can be shifted relative to one other and transversely to the direction of conveyance. The shifting is preferably carried out automatically with a drive 17 and spindles 26 , which engage the beams 22 - 25 . Preferably, the centering members 27 - 30 can be shifted independently of one another. The shifting is carried out by a suitable control unit. The centering members 27 - 30 extend downward as far as the rollers 34 and 35 . They preferably have profiling 50 on their lower edges, which is designed to correspond to the rollers 34 and 35 in such a way that the centering members 27 - 30 can be moved over the rollers 34 and 35 with as little clearance as possible. This makes it possible to ensure that the stacks 15 and 15 ′ cannot get stuck between a centering member 27 - 30 and the rollers 34 and 35 .
The centering members 27 - 30 can be adjusted in such a way that stacks 15 and 15 ′ can be transferred to the stack gripper 5 in a double infeed mode or in a single infeed mode. This is explained in greater detail below with reference to FIGS. 4 to 8 .
In the arrangement according to FIG. 4 , the stack infeed station 4 is set up for double infeed. The two chambers A and B have essentially the same design. The table 18 is positioned in such a way that one stack 15 at a time can be fed by the stack feeder 3 to chamber B. If a stack 15 is located in chamber B, the table 18 in FIG. 4 is shifted to the left, so that another stack 15 can be fed to the first chamber A. The two stacks 15 can be conveyed with the first conveying means 31 and the second conveying means 32 and delivered to the stack gripper 5 .
FIGS. 5 to 7 show the changeover of the stack infeed station 4 for single infeed. The individual steps can be carried out under automatic control.
First, the two centering members 27 and 28 are shifted into the position shown in FIG. 5 . These shifts are indicated by the double arrow 36 . The distance between the first centering member 27 and the second centering member 28 is reduced by this shift. The third centering member 29 and the fourth centering member 30 in FIG. 5 are then shifted to the right into the positions shown in FIG. 6 . The third centering member 29 is thus located some distance from the third conveying means 33 , as shown in FIG. 6 . In a further step, the distance between the third centering member 29 and the fourth centering member 30 is further increased by suitable shifting of these two members into the positions shown in FIG. 7 . Finally, the table 18 is moved into the position shown in FIG. 7 , which results in the formation of a relatively wide, second chamber B′, which is centered with respect to the stack feeder 3 , as shown in the drawing. The two conveying means 32 and 33 are located within the chamber B′. A relatively wide stack 15 ′ can be conveyed in the chamber B′. In this regard, the stack 15 ′ is simultaneously conveyed by the second conveying means 32 and the third conveying means 33 and is laterally guided by the third centering member 29 and the fourth centering member 30 . The stack 15 ′ can be essentially about twice as wide as a stack 15 . The stack 15 ′ alone is seized by the stack gripper 5 and set down on the pallet 11 . Naturally, a plurality of stacks 15 ′ can be successively conveyed in the chamber B′ and delivered to the stack gripper 5 . During this process, the first conveying means 31 are preferably inactive, and the relatively narrow, first chamber A′ is not used ( FIG. 8 ).
If a double infeed is necessary, the centering members 27 - 30 are brought back to the positions shown in FIG. 4 by making suitable shifts. This changeover can also be automatically controlled.
While specific embodiments of the invention have been shown and described in detail to illustrate the inventive principles, it will be understood that the invention may be embodied otherwise without departing from such principles.
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An infeed station has a stack feeder and a first and second chamber, which can each receive stacks from the stack feeder. The stacks can be conveyed in the chambers and can be transferred to a stack gripper with the conveyors assigned to the first chamber and the second chamber. First centering units serve to center the stacks in the first chamber, and second centering units serve to center the stacks in the second chamber. Third conveyors are arranged between the first and second conveyors. The first and second centering units can be shifted relative to each other so that the third conveyors are positioned in the first or second chamber, and the chamber with the third conveyors is much wider than the other chamber. The infeed station can be changed between double infeed with parallel processing of two stacks and single infeed with processing of only one stack of relatively great width at a time.
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CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of application Ser. No. 13/541,166 filed Jul. 3, 2012, which is a continuation of application Ser. No. 13/371,842, filed Feb. 13, 2012, which is a continuation of application Ser. No. 12/805,437, filed Jul. 30, 2010, which is a continuation of application Ser. No. 09/902,707, filed Jul. 12, 2001, which is a continuation of application Ser. No. 08/817,528, filed Aug. 5, 1997, which claims priority to International Application No. PCT/FR94/01185, filed Oct. 12, 1994, and French Application No. 95/08391, filed Jul. 11, 1995, the entire contents of each of which are hereby incorporated by reference in this application.
This application is related to our co-pending commonly assigned applications:
USSN 08/817,690
(Corres. to PCT/FR94/01185
filed Oct. 12, 1994);
USSN 08/817,689
(Corres. to PCT/FR95/01333
filed Oct. 12, 1995);
USSN 08/817,968
(Corres. to PCT/FR95/01335
filed Oct. 12, 1995);
USSN 08/817,437
(Corres. to PCT/FR95/01336
filed Oct. 12, 1995)
USSN 08/817,426
(Corres. to PCT/FR95/01337
filed Oct. 12, 1995); and
USSN 08/817,438
(Corres. to PCT/FR95/01338
filed Oct. 12, 1995).
BACKGROUND OF THE INVENTION
Field of the Invention
The invention relates to a communications process for a payment-triggered audiovisual reproduction system.
These audiovisual reproduction systems are generally found in cafes or pubs. This type of system is composed of a sound reproduction machine usually called a jukebox linked to a monitor which displays video images or video clips. To do this the jukebox is equipped with a compact video disk player and a compact video disk library and includes selection buttons which locate the titles of pieces of music which are available. Payment of a proper fee followed by one or more selections authorizes activation of the system with automatic loading in the player of the disk on which the selected piece is found, the desired audiovisual reproduction then being able to start.
These systems, although allowing faithful and good quality reproduction, nevertheless have major defects. Thus, a first defect relates to the space necessary for storing the library; this consequently entails that the system will have large dimensions and will be bulky. Likewise these systems which call on mostly mechanical hardware using sophisticated techniques have high fault rates; this is another defect. Finally, it is very unusual for all the pieces on a disk to be regularly heard; some are almost never played, but still cannot be eliminated. Besides this defect, the additional problems are caused by the companies which manage and distribute these systems. More particularly, placing in the circuit a limited number of identical disks and imposing a certain rotation on their customers sometimes results in an unpleasant wait for the customers when a disk is not available.
In addition, patent application PCT/WO 93 18465 discloses computerized jukeboxes which allow reception via a telecommunications network and a modem connecting the jukeboxes to the network, digital data comprising remotely loaded songs or musical pieces in a mass storage of the jukeboxes. The communications systems is likewise used for remote loading of representative files of digitized graphics information, the songs and graphics files being compressed before they are sent over the network. The jukebox processor then uses these files by decompressing them and sending the graphics data to the video circuit and the song data to the audio circuit.
However, the processor also manages the man/machine interface, and management of these different elements is done by sequentially displaying the graphics images representative of the song, then by responding to the touch action of the user, then checking that the user has paid the prescribed amounts, and finally when the required amount has been accounted, placing the selection in a queue for its subsequent performance. This system can only operate by first displaying the graphics images and then starting performance of the song because the processor cannot, according to the flowcharts, execute two tasks at one time. Finally, the graphics representations are uniquely data digitized by a scanner table of the album cover of the song. In no case does this jukebox allow display of moving images during the broadcast of the song or music. Likewise, since the processor is used for digital data decompression and processing for conversion into audio signals, it cannot consider the new actions of a user making a new selection. This is apparent, notably on page 12 of the PCT application, lines 25 to 27. Selection of new songs can only be done when the jukebox is in the attraction mode, i.e., the mode in which it displays graphics representations of different songs stored in the jukebox in succession.
U.S. Pat. No. 4,956,768 discloses a broadband server for transmitting music or images formed by a main processor communicating by a DMA channel with a hard disk and output cards, each controlled by a supplementary local processor which manages an alternative mode of access to two buffer memories A and B. Memory A is used to deliver, for example, musical data to a user, while the other is filled. Each of the output cards is connected to a consultation station, which can be local and situated in the same vicinity as the server or, alternatively, at a distance and connected by an audio or video communications network. The server receives data block-by-block and ensures that the sample parities are correct and rejects a block including more than two successive wrong samples. Each of these blocks is of course designated by a number. Once a block has been accepted, it can be stored on the local hard disk by recording its ordinal number which has no relation to its physical address on the hard disk. The consultation stations have audio and video outputs such as loudspeakers or headphones and a television monitor which makes it possible to listen to music or display images in response to requests received from terminals included in the consultation stations. In this system, the consultation stations where the first communications processor exists must have specific software for management of selection requests for musical pieces or video. It is only when the request has been made and addressed to the broadband server processor that it can transfer, under the authority of the local processor, the data in the buffer memories, such that this local processor ensures that the data are sent to the consultation stations. Moreover, it is specified that the output cards and buffer memories are filled only after having received the authorization of the local processor of the card.
Consequently, this system can only function within the framework of a multiprocessor device and does not in any way suggest use of this server for a jukebox controlled by a single processor operating in an multitask environment. This system proposed by this U.S. patent thus implements a complex process which allows delivery of a service to several consultation stations; this complex process is thus costly and incompatible with a system of jukeboxes, of which the cost and price should be as low as possible.
Moreover the process of downloading by a central site of digitized audio and video files to the local servers is accomplished via a specialized line communicating unidirectionally with the V35 interfaces of the local server, and allowing passage of 64 kilobit frames. Thus a second parallel communication must be established via the switched telephone network by a serial interface to allow exchange of service data. It is specified that it is preferable to transmit new musical pieces to the broadband server at night to leave the system free for users during the day, and that transmission can be done continuously and simultaneously for all local servers, provided that they can register continuously, i.e., at night.
This device can only work to the extent that the central server is the master and the local servers are slaved. This thus entails availability of local servers at the instant of establishing communications; this is enabled by the local servers having a double processor which relieves the communication processor for a sufficient interval. In a single-processor architecture it is thus difficult to establish communications according to this protocol determined with a variable number of jukebox stations to allow remote operations such as downloading of music or video following a selection by the jukebox manager or sending statistics to the center, or recovering data concerning billing or security management of the units, or recovery for analysis and survey distribution.
The object of the invention is to eliminate the various aforementioned defects of the systems of the prior art, and to provide a system of communications between jukebox units allowing reproduction and display of audiovisual digital information and a central server which supports, among various functions, downloading of data.
This object is achieved by the communications process operating in a conference mode and it includes the following stages:
sending a heading before any transaction which includes the identity of the destination, identity of the sender, and the size of the packets;
sending a server response in the form of a packet of data, each packet sent by the server being encoded using the identification code of the jukebox software;
receiving a data packet by the decoding jukebox, wherein the packet at the same time checks the data received using the CRC method and sending a reception acknowledgment to the server indicating the accuracy of the received data to allow it to prepare and send a new packet to the unit destination.
According to another operating mode the server can send the data by stream, the stream including several packets, and the receiver unit will then perform decoding and storage, and after receiving the indicator of the last packet, will signal the defective packets received at the server.
According to another feature, each packet contains a first field allowing identification of the seller, a second field allowing indication of the identification of an application, this 32 bit field making it possible to specify whether it is a digital song, digital video, stationary image, software update, statistics, billing, or update of the unit database, a third field indicating the identification of a single type of application such as the identification number of the product, the type of billing, the difference between a midi song and a digital song, last block indication, finally a fourth field indicating the sequence number of the block in the transmission, a fifth block indicating the length of this block in octets, a sixth field composed of variable length data, a seventh field composed of cyclic redundancy verification data.
An object of the invention is to eliminate the various defects of the systems of the prior art by providing an intelligent digital audiovisual reproduction system which is practical to implement, compact, reliable, authorizes storage at the title level as well as easy deletion or insertion of titles not listened to or wanted, all this while maintaining performance and a high level of reproduction quality.
Another object of the invention is to provide a standard protocol which moreover allows the features mentioned above for remote updating of software.
The objects are achieved by the fact that the jukebox units contain software for interpretation of the second field of the communications packets which detect the code corresponding to remote updating of the software and after having verified that the software version number is greater than the version installed on the unit, initiates a system status verification procedure to ensure than there is no activity underway on the jukebox. If yes, the unit displays a wait message, during reception of the new software version on the screen, copies the back-up of the software version installed on the unit, modifies the system startup file for startup with the backup version, then begins execution of the new version of the software, verifies the state of system status after execution of this new version, reinitializes the system startup files for startup with the new version. In the case in which the status is not OK, the software reinitializes the system with the old version and signals a reception error to the central server.
According to another feature, each audiovisual reproduction system contains a multitask operating system which manages, using a primary microprocessor, the video task, the audio task, the telecommunications task, the input task (keyboard, screen, touch) and a status buffer is linked to each of the tasks to represent the activity or inactivity of this task.
BRIEF DESCRIPTION OF THE DRAWINGS
Other advantages and features of the invention follow from the following description, with reference to the attached drawings, given by way of a non-limiting example only, in which:
FIG. 1 shows a circuit diagram of the hardware comprising the invention;
FIG. 2 shows an organizational chart of the service modules specific to a task and managed via a multitask operating system, the set of modules being included in a library stored in the storage means;
FIG. 3 shows the organization of the multitask system which manages the set of hardware and software;
FIG. 4 shows a flowchart describing the operation of the multitask management system;
FIG. 5 shows a flowchart for verifying task activity;
FIG. 6 schematically shows the database structure;
FIG. 7 shows the structure of the packets used in the communications protocol;
FIG. 8 shows a method of updating the software which can be done using the invention protocol.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Preferably, but in a nonrestrictive manner, the audiovisual reproduction system uses the aforementioned listed components.
Microprocessor central unit 1 is a high performance PC-compatible system, the choice for the exemplary embodiment being an Intel 80486 DX/2 system which has storage means and the following characteristics:
compatibility with the local Vesa bus,
processor cache memory: 256 kO,
RAM of 32 MO
high performance parallel and serial ports,
SVGA microprocessor graphics adapter,
type SCSI/2 bus type controller,
battery backed-up static RAM
Any other central unit with similar, equivalent or superior performance can be used in accordance with the invention.
This central unit controls and manages audio control circuit ( 5 ), telecommunications control circuit ( 4 ), input control circuit ( 3 ), mass storage control circuit ( 2 ), and display means control circuit ( 6 ). The display means consist essentially of a 14 inch (35.56 cm) flat screen video monitor ( 62 ) without interleaving of the SVGA type, with high resolution and low radiation, which is used for video reproduction (for example, the covers of the albums of the musical selections), graphics or video clips.
Likewise comprising part of the storage means, storage modules ( 21 ) using hard disks of the high speed and high capacity SCSI type are connected to the storage means already present in the microprocessor device. These modules allow storage of audiovisual data.
High speed 28.8 kbps telecommunications modem adapter ( 41 ) is integrated to authorize the connection to the audiovisual data distribution network controlled by a central server.
To reproduce the audio data of the musical selections, the system includes loudspeakers ( 54 ) which receive the signal from tuner amplifier ( 53 ) connected to electronic circuit ( 5 ) of the music synthesizer type provided to support a large number of input sources, while providing an output with CD (compact disk) type quality, such as for example a microprocessor multimedia audio adapter of the “Sound Blaster” card type SBP32AWE from Creative Labs Inc. on which two buffer memories ( 56 , 57 ) are added for a purpose to be explained below.
Likewise the control circuit of the display means includes two buffer memories ( 66 , 67 ) for a purpose to be explained below.
A thermally controlled 240 watt ventilated power supply provides power to the system. This power supply is protected against surges and harmonics.
The audiovisual reproduction system manages via its input controller circuit ( 3 ) a 14 inch (35.56 cm) touch screen “Intelli Touch” ( 33 ) from Elo Touch Systems Inc. which includes a glass coated board using “advanced surface wave technology” and an AT type bus controller. This touch screen allows, after having displayed on video monitor ( 62 ) or television screen ( 61 ) various selection data used by the customers, management command and control information used by the system manager or owner. It is likewise used for maintenance purposes in combination with external keyboard ( 34 ) which can be connected to the system which has a keyboard connector for this purpose, controlled by a key lock ( 32 ) via interface circuit ( 3 ).
Input circuit ( 3 ) likewise interfaces with the system a remote control set ( 31 ) composed for example of:
an infrared remote control from Mind Path Technologies Inc., an emitter which has 15 control keys for the microprocessor system and 8 control keys for the projection device.
an infrared receiver with serial adapter from Mind Path Technologies Inc.
A fee payment device ( 35 ) from National Rejectors Inc. is likewise connected to input interface circuit ( 3 ). It is also possible to use any other device which allows receipt of any type of payment by coins, bills, tokens, magnetic chip cards or a combination of means of payment.
To house the system a chassis or frame of steel with external customizable fittings is also provided.
Besides these components, wireless microphone ( 55 ) is connected to audio controller ( 5 ); this allows transformation of the latter into a powerful public address system or possibly a karaoke machine. Likewise a wireless loudspeaker system can be used by the system.
Remote control set ( 31 ) allows the manager, for example from behind the bar, access to and control of various commands such as:
microphone start/stop command,
loudspeaker muting command,
audio volume control command;
command to cancel the musical selection being played.
The system operating software has been developed around a library of tools and services largely oriented to the audiovisual domain in a multimedia environment. This library advantageously includes an efficient multitask operating system which efficiently authorizes simultaneous execution of multiple fragments of code. This operating software thus allows concurrent execution, in an orderly manner and avoiding any conflict, of operations performed on the display means, audio reproduction means as well as management of the telecommunications lines via the distribution network. In addition, the software has high flexibility.
The digitized and compressed audiovisual data are stored in storage means ( 21 ).
Each selection is available according to two digitized formats: hi-fi and CD quality.
Prior to describing and reading this organization chart in FIG. 2 , it must be noted that while all these modules described separately seem to be used sequentially, in reality the specific tasks of these modules are executed simultaneously in an environment using the multitask operating system. Consequently the organizational chart indicates the specific operations which the module must perform and not a branch toward this module which would invalidate all the operations performed by the other modules.
The first module, labeled SSM, is the system startup module. This module does only one thing, consequently it is loaded automatically when the system is powered up. If the system is started with a correct registration number it then directly enters the “in service” mode of the module labeled RRM.
The REG module is the registration mode module which, when it is activated for the first time or when approval for a new registration is necessary, indicates its software serial number and requests that the user enter his coordinates, such as the name of the establishment, address and telephone number.
The RMM module is the module of the “in service” mode which is the mode of operation which the system enters when its registration number has been validated. In this mode the system is ready to handle any request which can be triggered by various predefined events such as:
customers touching the screen: when a customer or user touches the screen, the system transfers control of the foreground session to the customer browsing and selection mode CBSM module,
telecommunications network server call requests: when the system detects a loop on the phone line, it emits an asynchronous background procedure: the telecommunications services mode TSM module,
requests concerning key switch ( 32 ): when the manager turns the key switch the system hands over control of its foreground session to the management mode SMM module,
reception of a remote control signal: when a command is received, it is processed in a background session by the system command 5MM module while the foreground session remains available for other interventions,
appearance of end of timing, showing inactivity of the system: when one of the various timers is activated, control is temporarily handed over to the inactivity routines IPM module for processing.
The system remains in the “in service” mode until one of the above described events takes place.
The IRM module is the inactivity routines module. It contains the routines which perform predetermined functions such as album cover display, broadcast of parts of musical pieces present in the system, reproduction of complete selections for internal promotional proposes, audio reproductions for external promotional purposes, spoken promotional announcements of new musical selections, withdrawal to an auxiliary source which can be called when the system is inactive and when a predefined but adjustable time interval corresponding to a timer has expired.
The SMM module is the system commands module. This module allows execution of functions which command the system to accept a required input by an infrared remote control device, these functions being handled instantaneously without the process underway being stopped. A very large number of these functions are possible, only some are listed below, in a nonrestrictive manner:
audio volume control of the played selections,
audio volume control of the auxiliary played source,
microphone start/stop command,
microphone audio volume control,
balance control, left channel, right channel,
control of base frequency level,
control of treble frequency level,
command to cancel or skip a musical selection,
panoramic effects command, zoom forward, zoom back,
triggering of reset of the software program.
The MMM module is the management mode module. This module is triggered when the key switch is turned by the manager. The display of an ordinary screen is replaced by a display specific to system management. With this new display the manager can control all the settings which are possible with remote control. He can likewise take control of additional low level commands allowing for example definition of commands to be validated or invalidated on the remote control. He is also able to define a maximum of high and low levels for each system output source, these limits defining the range available on the remote control. Using this screen the manager can access the mode of new selection acquisitions by touching a button located on the touch screen. When the manager has succeeded in defining these commands as well as the system configuration, it is then enough to remove the key and the system returns automatically to the “in service” mode.
The NSAM module is the new selections acquisition mode module.
The CBSM module is the customer browsing and selection mode module. Access to this module is triggered from the “in service” when the customer touches the screen. The display allows the user to view a menu provided for powerful browsing assisted by digitized voice messages to guide the user in his choice of musical selections.
The TSM module is the telecommunications services mode module between the central server and the audiovisual reproduction system. This module allows management of all management services available on the distribution network. All the tasks specific to telecommunications are managed like the background tasks of the system. These tasks always use only the processing time remaining once the system has completed all its foreground tasks. Thus, when the system is busy with one of its higher priority tasks, the telecommunications tasks automatically will try to reduce the limitations on system resources and recover all the microprocessor processing time left available.
The SSC module is the system security control module. This module manages security, each system is linked to a local controller system according to a preestablished time pattern for acquisition of the approval signal in the form of the registration number authorizing it to operate. In addition, if cheating has been detected or the system cannot communicate via the network, said system automatically stops working.
The SPMM module allows management of musical selections, songs or video queued by the system for execution in the order of selection.
Finally, the SMM module allows remote management of system settings by the manager by remote control.
The multitask operating system comprises the essential component for allowing simultaneous execution of multiple code fragments and for managing priorities between the various tasks which arise.
This multitask operating system is organized as shown in FIG. 3 around a kernel comprising module ( 11 ) for resolving priorities between tasks, task supervisory module ( 12 ), module ( 13 ) for serialization of the hardware used, and process communications module ( 14 ). Each of the modules communicates with application programming interfaces ( 15 ) and database ( 16 ). There are as many programming interfaces as there are applications. Thus, module ( 15 ) includes first programming interface ( 151 ) for key switch ( 32 ), second programming interface ( 152 ) for remote control ( 31 ), third programming interface ( 153 ) for touch screen ( 33 ), fourth programming interface ( 154 ) for keyboard ( 34 ), fifth programming interface ( 155 ) for payment device ( 35 ), sixth programming interface ( 156 ) for audio control circuit ( 5 ), seventh programming interface ( 157 ) for video control circuit ( 6 ), and last interface ( 158 ) for telecommunications control circuit ( 4 ).
Five tasks with a decreasing order of priority are managed by the kernel of the operating system, the first ( 76 ) for the video inputs/outputs has the highest priority, the second ( 75 ) of level two relates to audio, the third ( 74 ) of level three to telecommunications, the fourth ( 73 ) of level four to interfaces and the fifth ( 70 ) of level five to management. These orders of priority will be considered by priority resolution module ( 11 ) as and when a task appears and disappears. Thus, as soon as a video task appears, the other tasks underway are suspended, priority is given to this task and all the system resources are assigned to the video task. At the output, video task ( 76 ) is designed to unload the video files of the mass memory ( 21 ) alternately to one of two buffers ( 66 , 67 ), while other buffer ( 67 or 66 ) is used by video controller circuit ( 6 ) to produce the display after data decompression. At the input, video task ( 76 ) is designed to transfer data received in telecommunications buffer ( 46 ) to mass storage ( 21 ). It is the same for audio task ( 75 ) on the one hand at the input between telecommunications buffer ( 46 ), and buffer ( 26 ) of mass memory ( 21 ), and on the other hand at the output between buffer ( 26 ) of mass memory ( 21 ) and one of two buffers ( 56 , 57 ) of audio controller circuit ( 5 ).
The task scheduler module will now be described in conjunction with FIG. 4 . In the order of priority this module performs first test ( 761 ) to determine if the video task is active. In the case of a negative response it passes to the following test which is second test ( 751 ) to determine if the audio task is still active. In the case of a negative response third test ( 741 ) determines if the communications task is active. After a positive response to one of the tests, at stage ( 131 ) it fills memory access request queue ( 13 ) and at stage ( 132 ) executes this storage request by reading or writing in the mass storage, then loops back to the first test. When the test on communications activity is affirmative, scheduler ( 12 ) performs a test to determine if it is a matter of reading or writing data in the memory. If yes, the read or write request is placed in a queue at stage ( 131 ). In the opposite case, the scheduler determines at stage ( 743 ) if it is transmission or reception and in the case of transmission sends by stage ( 744 ) a block of data to the central server. In the case of reception the scheduler verifies that the kernel buffers are free for access and in the affirmative sends a message to the central server to accept reception of a data block at stage ( 747 ). After receiving a block, error control ( 748 ) of the cyclic redundancy check type (CRC) is executed and the block is rejected at stage ( 740 ) in case of error, or accepted in the opposite case at stage ( 749 ) by sending a corresponding message to the central server indicating that the block bearing a specific number is rejected or accepted, then loops back to the start tests. When there is no higher level task active, at stage ( 731 or 701 ) the scheduler processes interface or management tasks.
Detection of an active task or ready task is done as shown in FIG. 5 by a test 721 to 761 respectively on each of the respective hardware or software buffers ( 26 ) of the hard disk, ( 36 ) of the interface, ( 46 ) of telecommunications, ( 56 and 57 ) of audio, ( 66 and 67 ) of video which are linked to each of respective controller circuits ( 2 , 3 , 4 , 5 , 6 ) of each of the hardware devices linked to central unit ( 1 ). Test ( 721 ) makes it possible to check if the data are present in the buffer of the disk input and output memory, test ( 731 ) makes it possible to check if the data are present in the buffers of the hardware or software memory buffers of the customer interface device, test ( 741 ) makes it possible to check if the data are present in the buffers of the hardware or software memory of the telecommunications device, test ( 751 ) makes it possible to check if the data are present in the buffer of the hardware or software memory for the direction, test ( 761 ) makes it possible to check if the data are present in the hardware or software memory buffers of the video device. If one or more of these buffers are filled with data, scheduler ( 12 ) positions the respective status buffer or buffers ( 821 ) for the hard disk, ( 831 ) for the interface, ( 841 ) for telecommunications, ( 851 ) for audio, ( 861 ) for video corresponding to the hardware at a logic state illustrative of the activity. In the opposite case the scheduler status buffers are returned at stage ( 800 ) to a value illustrative of inactivity.
Due, on the one hand, to the task management mode assigning highest priority to the video task, on the other hand, the presence of hardware or software buffers assigned to each of the tasks for temporary storage of data and the presence of status buffers relative to each task, it has been possible to have all these tasks managed by a single central unit with a multitask operating system which allows video display, i.e., moving images compared to a graphic representation in which the data to be processed are less complex. This use of video display can likewise be done without adversely affecting audio processing by the fact that audio controller circuit ( 5 ) includes buffers large enough to store a quantity of compressed data sufficient to allow transfer of video data to one of video buffers ( 66 , 67 ) during audio processing while waiting for the following transfer of audio data.
Moreover, the multitask operating system which includes a library containing a set of tools and services greatly facilitates operation by virtue of its integration in the storage means and the resulting high flexibility. In particular, for this reason it is possible to create a multimedia environment by simply and efficiently managing audio reproduction, video or graphics display and video animation. In addition, since the audiovisual data are digitized and stored in the storage means, much less space is used than for a traditional audiovisual reproduction system and consequently the congestion of the system according to the invention is clearly less.
Database ( 16 ) is composed, as shown in FIG. 6 , of several bases: first ( 161 ) with the titles of the audiovisual pieces, second ( 162 ) with the artists, third ( 163 ) with the labels, fourth ( 164 ) with albums, fifth ( 165 ) with royalties. First base ( 161 ) contains first item ( 1611 ) giving the title of the piece, second item ( 1612 ) giving the identification of the product, this identification being unique. Third item ( 1613 ) makes it possible to recognize the category, i.e., jazz, classical, popular, etc. Fourth item ( 1614 ) indicates the date of updating. Fifth item ( 1615 ) indicates the length in seconds for playing the piece.
Sixth item ( 1616 ) is a link to the royalties base. Seventh item ( 1617 ) is a link to the album. Eighth item ( 1618 ) is a link to the labels. Ninth item ( 1619 ) gives the purchase price for the jukebox manager;
Tenth item ( 1620 ) gives the cost of royalties for each performance of the piece;
Eleventh item ( 1610 ) is a link to the artist database. This link is composed of the identity of the artist. The artist database includes, besides the identity of the artist composed of item ( 1621 ), second item ( 1622 ) composed of the name of the artist or name of the group. The label database includes first item ( 1631 ) composed of the identity of the label, establishing the link to eighth item ( 1618 ) of the title database and second item ( 1632 ) composed of the name of the label. The album database contains first item which is the identity of the album ( 1641 ) which constitutes the link to seventh item ( 1617 ) of the title base. Second item ( 1642 ) comprises the title, third item ( 1643 ) is composed of the date of updating of the album, and fourth item ( 1644 ) composed of the label identity. The royalty base is composed of first item ( 1651 ) giving the identity of the royalty and corresponds to sixth item ( 1616 ) of the title base. Second item ( 1652 ) comprises the name of the individual receiving the royalties. Third item ( 1653 ) is composed of the destination address of the royalties. Fourth item ( 1654 ) is composed of the telephone and fifth item ( 1655 ) is composed of the number of a possible fax.
It is apparent that this database ( 16 ) thus makes it possible for the manager to keep up to date on costs, purchases of songs and royalties to be paid to each of the artists or groups of artists performing the songs or videos, this provided that a communications protocol allows loading of the songs and modification of the content of the database depending on the songs loaded and allows communications with the central server by uploading or downloading the corresponding information. This communication protocol is composed of a first stage during which the center requests communication with the unit to which the communication is addressed. The unit decodes the heading sent by the center and if it recognizes it, indicates to the center if it is available or not depending on the state of its system status determined as explained above. If it is not available the center will then send a new request. If it is available, the center begins to send a first data block and the following blocks in succession. Each of the blocks is composed of a plurality of fields as shown in FIG. 7 . First field ( 810 ) indicates the identification number of the seller; this allows multiple sellers to share a single communications link with the central site. Second field ( 811 ) indicates the application identity and makes it possible to distinguish between a digital song, a digital motion video, a stationary video or an stationary digital graphical image, allows updating of software, transmission of statistics, billing, updating of the database, transmission of surveys. Third field ( 812 ) makes it possible to identify a subtype of application such as the identity number of the product, type of billing, indication of a song in the MIDI standard or a digital song, or finally indication of whether it is the last block of a transmission. The following field ( 813 ) makes it possible to recognize the number of the block assigned sequentially to the block in this transmission. Fourth field ( 814 ) makes it possible to recognize the octet length of each transmission block. Fifth field ( 815 ) makes it possible to recognize variable length data of the transmission and sixth field ( 816 ) contains cyclic redundancy verification information which allows the jukebox to verify that there has not been any error in transmission by recomputing the values of this information from the received data. The data are coded with the identification number of the receiving station, i.e., the number of the jukebox; this prevents another station from receiving this information without having to pay royalties. This is another advantage of the invention because in the processes of the prior art it is not exactly known which stations have received messages and at the outside a cheat could indicate that the information has not been correctly received to avoid having to pay the royalties. Here this operation is impossible since the cheat does not have access to his identification number known solely by the computer and encoding done using this secret identification number makes it possible to prevent cheating and reception by other units not authorized to receive the information. Finally it can be understood that this protocol, by the information which the blocks contain, allows high flexibility of use, especially for transmitting video images or digitized songs, or again to allow updating of software as explained below according to the process in FIG. 8 . In the case of software updating, the central system sends at stage ( 821 ) a first start signal allowing the jukebox for which it is intended to be recognized by its identification number and to indicate to this jukebox the number of the software version. At this stage ( 821 ) the jukebox then performs an initial verification to ensure that the version number is higher than the number of the versions installed and then initiates the process of verification of the system status indicated by stage ( 801 ). This verification process has already been described with reference to FIG. 7 . In the case in which at stage ( 822 ) there is no system activity, at stage ( 823 ) the jukebox initiates display of a waiting message on the display device to prevent a user from interrupting the communication, and during this time receives the data composed of the new software to be installed. At stage ( 824 ) the unit backs up the current version and at stage ( 825 ) the unit modifies the startup file for startup with the backup version. After having completed this modification the unit at stage ( 826 ) applies the software received to the system software and restarts the system software at stage ( 827 ). After having restarted the system, the unit reverifies status ( 801 ) and at stage ( 828 ) determines if the system statuses are valid or not. In the case in which no errors are detected, at stage ( 829 ) the unit updates the startup files with the newly received version and returns to a waiting state. If an error is detected, the unit reinitializes the system at stage ( 830 ). Once installation is completed, the unit awaits occurrence of an event representative of a task in order to handle its tasks as illustrated above.
Due to the flexibility of the multitask system and its communications protocol, each unit of the jukebox can thus be selected independently of the units connected to the network and can update the databases or the version of the desired song or again the software version without disrupting the operation of the other units of the network and without having to wait specifically for all the units of a network to be available. This is independent of the modems used which can be of the high speed type for a standard telephone line or a specialized modem on a dedicated data link or a SDN modem for fiber optic transmission or again an IRD modem for satellite connection.
If one or more packets are not received correctly by the jukebox during transmission, it does not interrupt transmission since other jukeboxes can also be in communication. However when communication is stopped by the central server, each jukebox which has had a incident takes a line and signals the numbers of the packets not received to the center. This allows the center to resend them. If registration of one or more songs or videos or part of a song or video has not be done due to lack of enough space on the disk or storage means, the system of each jukebox signals to the manager by a display or audio message the packet number if it is part of a song or a video, or the numbers of the song or video which have not be registered for lack of space. This allows the manager, after having decided to erase certain songs or videos from the hard disk, to again request that the center send these songs or videos or the part not received.
Any modification by one skilled in the art is likewise part of the invention. Thus, regarding buffers, it should be remembered that they can be present either physically in the circuit to which they are assigned or implemented by software by reserving storage space in the system memory.
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Method for communication between a central server and a computerized juke-box which operates in a conference mode, including: sending a header before any transaction, which includes the identity of the destination together, the identity of the emitter, and the size of the packets; responding from the server in the form of a data packet, each packet sent by the server being encoded using the identification code of the juke-box software; and receiving a data packet by the juke-box, which decodes the packet, simultaneously performs a check on the data received by the CRC method and sends an acknowledgement of receipt to the server indicating the accuracy of the information received, to allow it to prepare and send another packet to the juke-box.
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RELATED APPLICATIONS
The present application is a divisional application of U.S. application Ser. No. 09/890,731, filed on Aug. 2, 2001, now U.S. Pat. No. 6,605,174 which is a U.S. national application of PCT Application No. PCT/IL00/00018, filed on Jan. 9, 2000.
FIELD OF THE INVENTION
The invention relates to foil printing and in particular to transferring foil color from a foil and adhering the color to portions of an image.
BACKGROUND OF THE INVENTION
In foil printing, a colored foil bonded to a backing, hereinafter referred to as a “foil backing” is transferred from the foil backing to a substrate to form an image or parts of an image on the substrate. Hereinafter, the colored foil and its foil backing are referred to as a “printing foil”. In foil printing on paper, generally, the paper is printed with a desired image using a conventional printing press and conventional printing inks. The image is then printed with an adhesive, hereinafter referred to as a “foiling adhesive”, in those areas of the image to which it is desired to transfer the foil. The foiling adhesive is usually a dry toner “printed” in a xerographic process, in which the toner is bonded to the paper by fusing. A printing foil having a desired color foil is then pressed to the paper and heated. The heating causes the printed toner to melt and become tacky. The printing inks on the other hand are substantially unaffected by the heat and pressure. The foil sticks to the tacky toner but not the printed inks. When the printing foil is removed, foil detaches from the foil backing and adheres to the foiling adhesive to cover the areas of the image that it is desired to foil print. Foils are generally metallic and are often used for special printing effects, such as for example, to print gold and purple metallic color details on feathers of an image of a peacock or to gild a name on a business card.
When foil printing an image, the transfer of a foil to only desired areas of the image requires that areas of the image that are not to be foil printed not stick to the foil when the printing foil bearing the foil is pressed to the image and heated. In many printing processes an image is printed on paper by depositing toners of appropriate colors on the paper and fusing the toners to the paper. Toners used to print an image are fused to paper similarly to the way that toner used as a foiling adhesive in a conventional foil printing process is bonded to a printed image. If a printing foil is pressed to an image printed with toners and heated, the toner melts and foil adheres to all printed areas of the image that contact the printing foil. When an image is printed with toners it is therefore not practical to foil print only parts of the image using conventional foil printing processes. It is certainly not practical to foil print only fine details of such an image, such as for example details of the feathers of the peacock image noted above.
SUMMARY OF THE INVENTION
An aspect of some preferred embodiments of the present invention relates to providing a method for foil printing selected areas of an image printed with toners.
An aspect of some preferred embodiments of the present invention relates to providing a foiling adhesive for foil printing the image that has a melting temperature that is less than the melting temperature of the toners used to print the image.
To foil print an image printed with the toners the foiling adhesive is printed on those areas of the image to which it is desired to apply a foil. A printing foil is pressed to the image and heated to a temperature that is above the melting temperature of the foiling adhesive and below the melting temperature of the toners. The foiling adhesive becomes tacky and sticks to the foil. The toners do not become tacky and do not stick to the foil because the temperature to which the printing foil is heated is below the melting temperature of the toners. When the printing foil is removed from the image, after cooling, foil is left only on those areas of the image printed with the foiling adhesive.
An aspect of some preferred embodiments of the present invention relates to providing a printing foil having its foil covered with a protective “non stick” layer that retards adhesion of the foil to the toners but not to the foiling adhesive when the printing foil is pressed to the image and heated.
In a preferred embodiment of the present invention, the foiling adhesive has a higher melting temperature than the toners used to print the image. When the printing foil is pressed to the image and heated to a temperature above the melting temperature of the adhesive its foil sticks to the adhesive but not to the toners. During heating of the printing foil, heat from the foil softens the toners. Preferably, the toners are highly viscous at the melting temperature of the adhesive so that the toners do not flow during the foil printing process.
There is therefore provided in accordance with a preferred embodiment of the present invention a method for producing a printed image having a region that is foil printed comprising: printing at least one region of the image with a toner; printing the region of the image to be foil printed with a foiling adhesive that sticks to a foil on a printing foil, which adhesive has a melting temperature lower than the melting temperature of the toner; and pressing the printing foil to the image and heating the printing foil to a temperature greater than the melting temperature of the foiling adhesive and less than the melting temperature of the toner.
Preferably, the toner comprises a material from the group of materials consisting of ethylene methacrylic acid copolymer and ionomers of ethylene methacrylic acid copolymer. In some preferred embodiments of the present invention the toner comprises ethylene methacrylic acid copolymer. In some preferred embodiments of the present invention the toner comprises an ionomer of ethylene methacrylic acid copolymer.
Alternatively or additionally the adhesive comprises a material chosen from the group of materials consisting of: ethylene acrylic ester maleic anhydride terpolymer; low molecular weight ethylene acrylic acid copolymer; ionomers of low molecular weight ethylene acrylic acid copolymer; and esters of ethylene acrylic acid copolymer.
In some preferred embodiments of the present invention the adhesive comprises ethylene acrylic ester maleic anhydride terpolymer. In some preferred embodiments of the present invention the adhesive comprises low molecular weight ethylene acrylic acid copolymer. In some preferred embodiments of the present invention the adhesive comprises an ionomer of low molecular weight ethylene acrylic acid copolymer. In some preferred embodiments of the present invention the adhesive comprises an ester of ethylene acrylic acid copolymer.
There is further provided in accordance with a preferred embodiment of the present invention a method for producing a printed image having a region that is foil printed comprising: printing at least one region of the image with a toner; printing the region of the image to be foil printed with a foiling adhesive; covering a foil side of a printing foil with a layer of material that sticks to melted foiling adhesive but not to the toner; and pressing the printing foil to the image and heating the printing foil to a temperature greater than a tacking temperature of the foiling adhesive.
Preferably the layer of material that doesn't stick to toner comprises a material chosen from the group of materials consisting of: methacrylic copolymer resin; polyester; polyvinyl chloride; and polycarbonate.
In some preferred embodiments of the present invention the non-stick layer comprises methacrylic copolymer resin. In some preferred embodiments of the present invention the non-stick layer comprises polyester. In some preferred embodiments of the present invention the non-stick layer comprises polyvinyl chloride. In some preferred embodiments of the present invention the non-stick layer comprises polycarbonate.
Additionally or alternatively the toner comprises a material chosen from the group of materials consisting of: ethylene methacrylic acid copolymer and ionomers of ethylene methacrylic acid copolymer; low molecular weight ethylene acrylic acid copolymer and ionomers of low molecular weight ethylene acrylic acid copolymer; esters of ethylene methacrylic acid; and esters of ethylene acrylic acid.
In some preferred embodiments of the present invention the toner comprises ethylene methacrylic acid copolymer. In some preferred embodiments of the present invention the toner comprises ionomer of ethylene methacrylic acid copolymer. In some preferred embodiments of the present invention the toner comprises low molecular weight ethylene acrylic acid copolymer. In some preferred embodiments of the present invention the toner comprises an ionomer of a low molecular weight ethylene acrylic acid copolymer. In some preferred embodiments of the present invention the toner comprises an ester of ethylene methacrylic acid. In some preferred embodiments of the present invention the toner comprises an ester of ethylene acrylic acid.
Additionally or alternatively, the adhesive comprises a material chosen from the group of materials consisting of styrene acrylic acid copolymer; polyamide; ethylene acrylic ester maleic anhydride terpolymer. In some preferred embodiments of the present invention the adhesive comprises styrene acrylic acid copolymer. In some preferred embodiments of the present invention the adhesive comprises polyamide. In some preferred embodiments of the present invention the adhesive comprises ethylene acrylic ester maleic anhydride terpolymer.
There is further provided in accordance with a preferred embodiment of the present invention a printing foil for foil printing a region of an image comprising: a substrate; a layer of foil bonded to the substrate; and a layer covering the foil formed from a material chosen from the group of materials consisting of methacrylic copolymer resin, polyester, polycarbonate and polyvinyl chloride.
In some preferred embodiments of the present invention the layer covering the foil comprises methacrylic copolymer resin. In some preferred embodiments of the present invention the layer covering the foil comprises a polyester. In some preferred embodiments of the present invention the layer covering the foil comprises polycarbonate. In some preferred embodiments of the present invention the layer covering the foil comprises polyvinyl chloride.
BRIEF DESCRIPTION OF FIGURES
The invention will be more clearly understood from the following description of preferred embodiments thereof read with reference to figures attached hereto. In the figures, identical structures, elements or parts that appear in more than one figure are generally labeled with the same numeral in all the figures in which they appear. Dimensions of components and features shown in the figures are chosen for convenience and clarity of presentation and are not necessarily shown to scale. The figures are listed below.
FIG. 1 shows a schematic image of a parrot printed using toners that is to have its wings and tail feathers foil printed with an iridescent green metallic color, in accordance with a preferred embodiment of the present invention;
FIG. 2 schematically shows the parrot shown in FIG. 1 after foil printing in accordance with a preferred embodiment of the present invention;
FIGS. 3A and 3B show schematically in cross section view foil printing the parrot shown in FIGS. 1 and 2 , in accordance with a preferred embodiment of the present invention; and
FIGS. 4A and 4B show schematically in cross section view foil printing the parrot shown in FIGS. 1 and 2 , in accordance with another preferred embodiment of the present invention.
DESCRIPTION OF PREFERRED EMBODIMENTS
FIG. 1 schematically shows an image of a parrot 20 printed on paper 22 with toners that is to be foil printed in accordance with a preferred embodiment of the present invention. The image of parrot 20 is partitioned into various bounded color regions 24 . A letter in a bounded color region 24 represents a particular color toner with which the region is printed. For example, the letters Y, R, B, O shown in FIG. 1 might represent bright yellow, red, blue and orange toner respectively. The toners have a melting temperature T 1 . A shoulder feather color region 26 and tail feather color regions 28 , are to be foil printed with an iridescent metallic green and are printed, in a preferred embodiment of the invention, with a foiling adhesive which is represented by the letters AD, having a melting temperature T 2 , which is less than T 1 .
In a preferred embodiment of the present invention toners are liquid toners such as those described in U.S. Pat. No. 5,407,771 to Landa et al. Preferably, the toners comprise ethylene methacrylic acid copolymer made by Du Pont and sold under the trade name Nucrel 699. Nucrel 699 has a melting temperature T 1 between about 110° C.–120° C. Preferably the toners are toners produced and sold by Indigo N. V. of the Netherlands under the trade names El-Mark 3.0 and EI-Mark 3.1 Other toners suitable for use with the present invention are based on: ethylene methacrylic acid low copolymers sold by Du Pont under the trade names NUCREL resins 599 and 925 and their ionomers, sold by Du Pont under the trade name SURLYN. Esters of these materials can also be used.
Preferably, a foiling adhesive used with these toners that has a melting temperature less than the toners comprises ethylene acrylic ester maleic anhydride terpolymer, manufactured by ELF Atochem and sold under the trade name Lotader 8200. Lotader 8200 has a melting temperature T 2 of about 100° C.
To prepare a quantity of the foiling adhesive, 1800 g of Isopar-L made by Exxon and 1200 g of Lotader 8200 is loaded into a four gallon size Ross double planetary mixer that is preheated to about 140° C. The stirring speed of the mixer is set to stirring speed 6 and the loaded materials are stirred for about 1.5 hours until the mixture reaches a temperature of about 118° C. When the mixture reaches about 118° C. the stirring speed is reduced to stirring speed 3 and the mixture is air fan cooled for about three hours until the mixture temperature reaches about 40° C. 1150 g of the mixture, 2.3 g of aluminum stearate (mfg. by Riedel de Haen) and 1147.7 g Isopar-L are then ground together at 250 rpm in a 1 S attritor (mfg. by Union Process) loaded with 3/16″ carbon steel balls for about 26 hours at 40° C. The ground mixture is dispersed in a non-polar liquid such as an Isopar-L with a ratio by weight of mixture to dispersant of about 4% to provide the foiling adhesive.
Foiling adhesive can also be prepared, in accordance with a preferred embodiment of the present invention, using a procedure similar to that described above in which Lotader 8200 is replaced with Lotader 5500 or Lotader 6200/5500. Adhesives suitable for use in the present invention can also be similarly produced using ethylene acrylic acid low molecular weight copolymers AC 540 and AC 5120 (Allied Signal) or their low molecular weight ionomers AC 293 or 295 (Allied Signal), ethylene methacrylic acid (ester); and esters of ethylene acrylic acid copolymers.
To foil print iridescent green on shoulder and tail feather regions 26 and 28 , a printing foil (not shown) having an iridescent green foil is pressed to the image of parrot 20 and heated to a temperature T 3 , which satisfies the relationship T 2 <T 3 <T 1 , using methods known in the art. At temperature T 3 , foiling adhesive AD printed in shoulder and tail feather regions 26 and 28 melts and sticks to the iridescent green color on the printing foil. Toners, which having a melting temperature T 1 >T 3 , do not melt and therefore do not stick to the iridescent green foil. When the printing foil is removed from the image of parrot 20 , the iridescent green color covers substantially only shoulder and tail feather regions 26 and 28 . FIG. 2 schematically shows the image of parrot 20 shown in FIG. 1 after foil printing, in accordance with a preferred embodiment of the present invention. The iridescent green is represented by shading and covers only shoulder and tail feather regions 26 and 28 .
FIG. 3A schematically shows a cross section 30 of a portion 32 of the image of parrot 20 being foil printed with iridescent green using a printing foil 34 , in accordance with preferred embodiment of the present invention. The cross section is taken along a bold line 36 shown in FIG. 2 . Printing foil 34 preferably comprises a thin substrate 38 on which a layer 40 of iridescent green foil is deposited using methods known in the art. A block arrow 44 schematically represents a pressure with which printing foil 34 is pressed to image portion 32 . Printing foil 34 is heated to a temperature T 3 shown in parentheses besides the numeral 34 .
Image portion 32 of parrot 20 comprises a region 46 of paper 20 on which parrot 20 is printed, which is printed with toner B, and a region 48 , which is printed with adhesive AD, in accordance with a preferred embodiment of the present invention. Toner B has a melting temperature T 1 (which is greater than T 3 ) shown in parentheses besides numeral 46 . Adhesive AD has a melting temperature T 2 (which is less than T 3 ) shown in parentheses besides numeral 48 . FIG. 3B schematically shows printing foil 34 partially removed from image portion 32 of parrot 20 following transfer of foil to image portion 32 . A portion 40 ′ of foil layer 40 that was pressed to foiling adhesive AD has separated from printing foil substrate 38 and is bonded to foiling adhesive AD. Substantially no foil is bonded to toner B, in accordance with a preferred embodiment of the present invention.
Parrot 20 can also be foil printed using a printing foil having its foil covered with a nonstick layer that prevents adhesion of the foil to the toners, in accordance with a preferred embodiment of the present invention, even if adhesive AD has a higher melting temperature than the toners. Preferably, the foiling adhesive AD is applied to shoulder feather color region 26 and tail feather color regions 28 in a dry xerography process. Preferably the adhesive is styrene acrylic acid copolymer, which has a melting temperature of about 160° C. This may be in the form of a powder toner or a liquid toner. When in powder form, preferably the powder is a colorless powder prepared by methods known in the art. Other adhesives suitable for use in the present invention can also be formed using a polyamide or Lotader 5500, 6200/5500 or 8200 as described above.
Preferably, a non-stick layer that adheres to the adhesive but retards adhesion of a foil to the toners in the image is formed from one of the family of methacrylic copolymer resins made by Du Pont that are sold under the trade names Elvacite 2014, 2016, 2043 and 2044. Non stick layers in accordance with preferred embodiments of the present invention can also be formed using polyesters, polycarbonate and polyvinyl chloride.
At a working temperature, preferably marginally greater than about 160° C. when for example styrene acrylic acid copolymer is used as an adhesive, to which a foil is heated to transfer foil to regions 26 and 28 , toners printed in color regions 24 melt. However, at the working temperature the toners are viscous and do not flow substantially during the time that foil is being transferred from the printing foil to shoulder feather region 26 and tail feather regions 28 . As a result, the heat and pressure to which the image of the parrot is subjected during the foil printing process do not substantially degrade the quality of the image.
Toners printed in color regions 24 that may be used with the non-stick layer, in accordance with a preferred embodiment of the present invention are toners based on Nucrel 699, such as Indigo N. V. toners EI-Mark 3.0 and EI-Mark 3.1 referenced above. Other toners suitable for use with the present invention are based on: ethylene methacrylic acid copolymers (sold by Du Pont under the trade names NUCREL resins 599 and 925 ) and their ionomers (sold by Du Pont under the trade name SURLYN); low molecular weight ethylene acrylic acid copolymers (trade names AC540 and AC 5120 by Allied Signal Inc.) and their ionomers (trade names ACRYN 293 and 295 by Allied Signal Inc); and esters of these materials.
FIGS. 4A and 4B schematically show a cross section view 50 of portion 32 , shown in FIGS. 3A and 3B , of the image of parrot 20 being foil printed with iridescent green using a printing foil 52 comprising a non-stick layer, in accordance with preferred embodiment of the present invention. In FIGS. 4A and 4B , unlike in FIGS. 3A and 3B , foiling adhesive AD, which covers region 48 of portion 32 , has a melting temperature T 2 that is greater than the melting temperature T 1 of toner B, which covers region 46 of portion 32 .
Printing foil 52 comprises a thin substrate 38 and a layer 40 of iridescent green foil. Foil layer 40 is covered with a layer 42 of non-stick material that does not stick to the toners used to print parrot 20 , in accordance with a preferred embodiment of the present invention. A block arrow 44 schematically represents a pressure with which printing foil 52 is pressed to image portion 32 . Printing foil is heated to a temperature T 3 that is greater, preferably marginally greater, than T 2 . Temperatures T 1 , T 2 and T 3 therefore satisfy the relationship T 1 <T 2 <T 3 . At temperature T 3 toner B softens and melts but does not stick to non-stick layer 42 . Furthermore, at temperature T 3 , the viscosity of toner B is sufficiently high so that during the foil printing process toner B does not flow substantially.
FIG. 4B schematically shows printing foil 52 partially removed from portion 32 of parrot 20 following transfer of foil to image portion 32 . A portion 42 ′ of nonstick layer 42 that was pressed to foiling adhesive AD is bonded to adhesive AD and has “carried with it” a portion 40 ′ of foil layer 40 , which has separated from printing foil substrate 38 . Substantially no portion of non-stick layer 42 and therefore of foil layer 40 is bonded to toner B, in accordance with a preferred embodiment of the present invention.
In the description and claims of the present application, each of the verbs, “comprise” “include” and “have”, and conjugates thereof, are used to indicate that the object or objects of the verb are not necessarily a complete listing of members, components, elements or parts of the subject or subjects of the verb.
The present invention has been described using detailed descriptions of preferred embodiments thereof that are provided by way of example and are not intended to limit the scope of the invention. The described preferred embodiments comprise different features, not all of which are required in all embodiments of the invention. Some embodiments of the present invention utilize only some of the features or possible combinations of the features. Variations of embodiments of the present invention that are described and embodiments of the present invention comprising different combinations of features noted in the described embodiments will occur to persons of the art. The scope of the invention is limited only by the following claims.
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A printing foil for foil printing a region of an image comprising:
a substrate; a layer of foil bonded to the substrate; and a layer covering the foil which layer is formed from a material chosen from the group of materials consisting of methacrylic copolymer resin, polyester, polycarbonate and polyvinyl chloride.
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BACKGROUND OF THE INVENTION
The present invention relates to a device for the stimulation of a body part and to a method for the stimulation of a body part with the aid of an external stimulation device.
The treatment of centrally induced paralyses is one of the central problem areas in medical research. Central paralyses may occur on account of brain damage or spinal cord injuries. They are frequently caused by stroke syndromes, congenital brain damage, brain tumours or external injuries. Central paralyses are often accompanied by painful spastic muscle cramps. At present, they cannot be adequately cured by either surgery or medication.
Central paralyses can currently only be treated by conventional physiotherapy or by activating nerves or muscles of the paralysed body part by electric stimuli. For this purpose, electrodes are attached on or under the skin of the paralysed body part, so that an electric field is generated in the region of the nerves or muscles to be activated of the paralysed body part. This can only lead to a restricted reactivation of the muscles. Permanent rehabilitation, and consequently curing of the paralysis, cannot be achieved in this way however. What is more, considerable pain often occurs in this treatment.
U.S. Pat. No. 5,620,463 discloses an electrophysiological conditioning system which has conditioning applicators which transmit electromagnetic conditioning signals suitable for bringing about basic physiological effects, such as relaxation of the nervous system, stimulation of the blood circulation and stimulation of normal cell repair and regeneration, and are suitable for enhancing the natural self-defence and healing mechanisms of man and animals. For this purpose, magnetizing coils, which generate a magnetic field when a current pulse is discharged through the coil, are used. Such a conditioning system is not suitable, however, for the treatment of central paralyses.
The object of the present invention is to provide a method and a device for the treatment of central paralyses in such a way that a permanent rehabilitation effect is brought about.
The invention provides a device and a method for the stimulation of a paralysed body part, with the aid of which a smooth and pain-free composite and coordinated movement of the body part concerned can be induced. The failure of the proprioceptive afferences (biosensors, for example neuromuscular spindles) caused by the paralysis is to be replaced as far as possible to stimulate the plastic capabilities of the central nervous system as early as possible by a neuromodulation.
The device according to the invention for the stimulation of a body part has at least the following elements: at least two coils S i with at least one power supply for the generation of magnetic fields at innervation zones of the body part, particularly preferably at end branches of motor nerve fibres and peripheral nerves, and a device for the open-loop or closed-loop control of the power supply (supplies) for the coils. In this case, the device for the open-loop or closed-loop control of the power supply (supplies) for the coils has at least a current pulse generator for the emission of current pulses I (S i ) at pulse frequencies f (I(S i )) and pulse durations d (I(S i )) through the power supply (supplies) to the coils S i , the emission of the current pulses taking place in such a way that the respective magnetic field pulses generate an electric field in the nerve paths, so that muscles of the body part are contracted or decontracted in a coordinated manner, so that a coordinated composite movement of the body part is obtained. This [lacuna] takes dependent factors into account, and an adaptation to neuronal erethisms takes place.
SUMMARY OF THE INVENTION
The device according to the invention consequently allows the generation of precisely defined movements of the centrally paralysed body part. These movements are often composed of a number of partial movements and simulate natural movements of the patient as faithfully as possible, for example grasping movements or walking movements. By a repetitive magnetic stimulation, primarily proprioceptive afferences are initiated both adequately by the induced movements and by direct activation of afferent nerve fibres. A regular repetition of induced movements can bring about a learning effect in the central nervous system, finally leading to the patient being able to perform the induced movements again independently (actively) with the paralysed body part. Starting from this partly rehabilitated state, the patient can then also re-learn other movements.
This method can basically be used for the treatment of any centrally paralysed body parts. It is not technically restricted to humans, but can also be used in the case of animals, for example racehorses, with local symptoms of paralysis.
The device according to the invention may have two or more coils S i . Preferably three, four or five coils are used for the stimulation of the paralysed body part. For simple movements, a single coil may also be used. These coils must be of such a type that they can be positioned over innervation zones of the paralysed body part in such a way that an electric field is produced there by induction when a current pulse I (S i ) passes through the coil S i .
Each coil S i preferably has a power supply, which generates the current pulses I (S i ) necessary for generating magnetic fields. However, a common power supply may also be used. These power supplies are controlled by a current pulse generator, which prescribes the point in time, frequency, duration and intensity of the current pulses I (S i ).
The current pulse generator generates the current pulses on the basis of prescribed patterns, which respectively correspond to certain composite sequences of movements, to be specific the physiological sequences of movements of the body part concerned. For this purpose, a multiplicity of patterns can be kept in a storage medium, which the current pulse generator can access at any time and which it can modify.
The intensity of the current pulses I (S i ) determines the field strength of the magnetic field respectively generated. The field strength of the magnetic field applied must exceed a certain threshold in order for a movement to be initiated. This threshold may vary with the body part concerned and with the patient.
The duration and frequency of the current pulses influence the performance of the induced movements, that is to say their roundness or angularity, to a considerable extent. However, the duration and frequency of the current pulses also have a great influence in the area of therapy. The pulse frequency f (I(S i )) preferably lies in a range from 10 Hz to 30 Hz, particularly preferably in a range from 15 Hz to 25 Hz. These frequencies lie in the physiological range for activating the muscles. A current pulse preferably corresponds here to a sinusoidal oscillation, on account of the optimization in terms of energy. The sinusoidal oscillation preferably has here, again with regard to its optimization in terms of energy, a period duration in a range from 1.9*10 −4 s to 3.77*10 −4 s, particularly preferably in a range from 1.19*10 −4 s to 2.15*10 −4 s. The segment extends preferably from 0 to a value in a range from 0 to 2π, particularly preferably to a value of k*π/4, where k is 1, 2, 3 or 4. In a further preferred embodiment, the sinusoidal oscillation is broken off at a value in the range from 0 to π/4, so that a high value for dI (S i )/dt is obtained, which brings with it an improved stimulation effect.
In a preferred embodiment, the device for the open-loop or closed-loop control of the power supply (supplies) for the coils S i has at least one sensor for sensing the momentary position of the body part, in order in this way to be able to control or regulate the power supply (supplies) for the coils correspondingly. Preferably, one or more, possibly also a combination, of the following sensors is used here: a position switch, preferably a 3-point switch, an angle potentiometer, an ultrasonic measuring system or an infrared camera. If angle-measuring potentiometers are used, an arrangement of three potentiometers, the angle signals of which are summated, is preferably chosen. As a result, the individual potentiometers do not have to be adapted exactly to the axis of the joint. In the case of an ultrasonic measuring system, ultrasonic transmitters are fastened at suitable points of the body part concerned. The signals of these transmitters are sensed by a fixed receiver with regard to their position. If infrared cameras are used, the position is calculated back from the image of two cameras by means of infrared LEDs fastened at suitable points of the corresponding body part.
In another preferred embodiment of the device, the device is specifically adapted to a particular patient, so that the device can also be used in a “feed-forward” mode without any sensors.
The device for the open-loop and closed-loop control of he power supply (supplies) for the coils preferably includes a closed-loop control unit which responds to a signal which represents at least one state parameter for at least one muscle of the body part. The state of a muscle comprises the mechanical expansion (elastic and damping factors) and the innervational, contractile muscle activation. This signal is preferably obtained from an electromyogram, which is measured at least one muscle of the body part. Electromyography represents a method of registering muscle action potentials. An electromyogram can consequently provide information on induced or voluntary, intended action potentials, by which the stimulated movement of the muscle concerned is supported. Consequently, not only the degree of paralysis and the rehabilitation already achieved but also the fatigue of the muscle can be determined. The influence of the support of the induced movements by the patient as a result of the patient's own willpower can also be quantitatively or qualitatively assessed with the aid of this method. This information makes it possible to adapt the current pulses I (S i ), that is to say their intensity, frequency and duration, to the specific treatment situation of the patient. In this way, the rehabilitation can be individualized and intensified.
The closed-loop control of the treatment can in principle take place at any time intervals, for example after every few seconds, which would mean constant monitoring of the situation, or else after every few days or weeks, which would be equivalent to keeping a general watchful eye on the rehabilitation steps.
In a further preferred embodiment of the invention, the device for the open-loop or closed-loop control of the power supply (supplies) for the coils S i has at least one sensor for sensing forces acting on the corresponding body part, to make it possible in this way for the power supply (supplies) for the coils to be controlled or regulated in an adapted manner. This sensor is preferably a pressure-dependent resistor. For this purpose, a piezoelectric capacitance measurement is carried out, for example, or strain gauges are used.
Preferably, a learning ;algorithm is integrated in the device for the open-loop or closed-loop control of the power supply (supplies) for the coils. During a stimulation, the stimulation result and effect are observed, analysed and recorded in a memory unit. This allows the stimulation effect to be optimized patient-specifically in successive cycles. As an alternative to this, the procedure may also be such that the movement is initially performed under open-loop control, after completion of the movement the actual position of the body part is compared with its desired position and then the control parameters are changed in such a way that the aim is achieved even better when the next stimulation is carried out. This type of “feed-forward” control corresponds more closely to the physiological situation. This control can be realized for example by several neuro-controllers (neuronal networks) or by an adaptive control device. In a further possible way of using the learning algorithm, the stimulation pattern is adapted to the physiological generation of signals.
Further advantages, features and application possibilities for the invention emerge from the following description of an exemplary embodiment in conjunction with the drawing, in which:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a functional diagram of a device according to the invention, the body part to be stimulated being a human arm.
FIG. 2 shows a flow diagram of the stimulation according to the invention of a muscle and body reactions induced as a result.
FIG. 3 shows a diagram of the variation over time of the force exerted by a muscle stimulated according to the invention, taking the secondary systems into account.
FIG. 4 shows a diagram of the variation over time of the force exerted by a muscle stimulated according to the invention, on the basis of the stimulation.
FIG. 5 shows a diagram of the variation over time of the force exerted by the antagonist.
FIG. 6 shows a functional diagram of a device according to the invention with peripheral devices.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 represents a functional diagram of a device according to the invention. The device represented here serves for the stimulation or neurostimulation of a human arm. Five coils 1 are arranged on the arm in such a way that, in the state in which current is flowing through, they can generate magnetic fields at innervation zones of a corresponding muscle or a corresponding group of muscles of the arm. The five power supplies 2 for the five coils 1 are activated by means of a current pulse generator 3 . The current pulse generator 3 is responsible for the generation of a corresponding current pulse pattern, which is necessary to achieve a stimulation of individual muscles or groups of muscles, which ultimately leads step by step to a certain selected movement of the arm, for example to bending of the arm. The stimulation of the muscles or groups of muscles must take place in this case in such a way that the muscles or groups of muscles are contracted or decontracted in a coordinated manner. Two coils 1 are in this case often not to be “operated”, i.e. supplied with current, simultaneously, in order to prevent an unfavourable interaction of the corresponding magnetic fields, in particular to avoid a positive superimposing of the magnetic fields and accompanying enormous fields strengths.
Before a pulse pattern can be generated in the current pulse generator 3 , a certain command is fed to the system by means of a closed-loop control unit 5 . This may either be an external command for carrying out a specific movement or a voluntary activation (intention) of the patient concerned for a certain movement. The latter is measured by an electromyogram 6 of corresponding muscles. Once a command is received, this command is converted in a first step into system-intelligible individual commands by the closed-loop control unit 5 . In a. further downstream closed-loop control unit 9 , these individual commands are converted into movement segments with an associated movement- and force-tracing trajectory for the movement of the arm and the hand. A movement- and force-tracing trajectory comprises a plurality of transition points, each transition point comprising presettings for the angle of the joint and force on the fingers for the arm and hand. In the current pulse generator 3 , a comparison between the desired position and the actual position is used as a basis for generating the current pulse patterns which respectively have to be emitted by the power supplies 2 for the coils 1 to the latter in order to stimulate the corresponding muscles or groups of muscles. For generating the pulse pattern, the current pulse generator 3 accesses a memory unit 10 which is integrated in the device and in which information specific to the body part or the patient is stored. With the aid of this information, consequently the current pulse pattern can be individually adapted and optimized. During a stimulation, the stimulation result and effect are observed and analysed by means of a learning algorithm 8 , in order then to be optimized for the subsequent cycle.
The joint-angle positions and forces on the thumb and index finger are sensed and fed back by means of sensors 4 , 7 and 11 , for example angle potentiometers with pressure sensing via pressure-dependent resistors. The feedback serves for controlling the current pulses necessary for the subsequent movement step, which are to be emitted by the power supplies 2 to the coils 1 . By measuring the forces on the thumb and index finger, a controlled grasping of objects or a force-controlled closing of the thumb and index finger for precision gripping is made possible.
This cycle is to be repeated until the prescribed movement has been completed, which is likewise established and reported by the sensors 4 and 7 .
The magnetic stimulation of a muscle as a result of a current pulse and its result on the stimulated muscle and the rest of the organism are illustrated on the basis of FIG. 2 . The stimulation and its results can be subdivided into three systems A, B and C.
In the main system A, a pulse is emitted by the current pulse generator 3 (cf. also FIG. 1 ), via the power supply 2 concerned, to the coil 1 concerned for the stimulation of a muscle 12 of the limb, on the basis of the desired coordinates and the actual coordinates of the limb. This stimulation acts on the muscle 12 to be stimulated and thereby causes a movement of the limb. The new coordinates of the limbs after the movement are measured and passed to the current pulse generator 3 as new actual coordinates. The force exerted by the stimulated muscle 12 , in the static case on a force-measuring instrument, for instance a pressure-dependent resistor, and in the dynamic case on an acceleration-measuring instrument, is denoted by F M1 (t)
Apart from this main system A, the movement of the limb is also influenced, however, by two secondary systems B and C. In the antagonistic secondary systems B, a movement of the antagonist 13 , that is of the muscle opposing the stimulated muscle 12 , is initiated by the movement of the stimulated muscle 12 . When the stimulated muscle 12 contracts, the antagonist 13 expands and thereby retards or, more correctly, balances the movement of the simulated muscle 12 . This takes place by an activation of the neuromuscular spindle 15 of the antagonist 13 , this activation leading via the spinal cord 14 , under the control of the central nervous system 18 , by reflex action to a contraction of the antagonist 13 . The force exerted by the antagonist 13 is denoted by F M2 (t)
The second secondary system C concerns the reflex coupling of the stimulated muscle 12 itself. By the movement of the stimulated muscle 12 , the stimulation of this muscle 12 is directly influenced via its neuromuscular spindle 16 and via the spinal cord 17 , under the control of the central nervous system 18 . This coupling of the stimulated muscle 12 is contained in the force F M1 (t). However, the coupling only contributes after a time delay to the contraction of the stimulated muscle 12 , so that its influence on the variation of the force F M1 (t) is not constant. While in healthy people these secondary systems are of minor significance, in patients with cerebral paralyses these secondary systems constitute very adverse factors for the force development of the stimulated muscle, due to the loss of inhibition of the reflexes.
The two secondary systems must be taken into account along with the main system in the stimulation of the muscle. This is because the movement of the limb follows the overall force F G (t), which represents the sum of the individual forces F M1 (t) and F M2 (t) To be able to control the effect of the stimulation, the result of a change in the stimulation on the movement of the limb must be determined. This requires the effects of the stimulation to be separated from the effects of the activation of the antagonist and the coupling. For this purpose, individual pulses are emitted by the current pulse generator at intervals of more than 5 seconds with increasing amplitude. This corresponds to weighted Dirac pulses. As a result, the system response of the main system of the muscle can be determined under the prescribed conditions.
FIG. 4 shows an example of the variation over time of the force F M1 (t). This variation can be described by the exponential function A*(exp(−t/T 1 )−exp(−t/T 2 )). In the ideal case, this variation of force is equal to the overall force F G (t). The actual variation of the overall force represented in FIG. 3 differs, however, from the ideal variation by having a sharper drop after the maximum. This difference is relatively small in healthy people, but of great significance in patients with cerebral paralyses. This variation of the overall force F G (t) can be approximated by the exponential function described above. The variation of force F M1 (t) is determined by this method. As can be seen in FIG. 2, the variation of the overall force F G (t) is obtained by a superimposing of the forces F M1 (t) and F M2 (t). It follows from this that the difference from the variation of the overall force F G (t) and the approximation by the exponential function F M1 (t) represents the variation of the force of the second muscle F M2 (t) on the basis of the antagonistic secondary system. The variation approximated by the exponential function is represented in FIG. 5 . In this way, the influence of the antagonist on the simulated contraction can be determined, while the coupling of the stimulated muscle cannot be separated.
On the basis of the simulation system now determined, the starting values for the stimulation can be determined. Consequently, the response of the stimulated muscle when repetitive pulses are applied can be predicted and the effect of the stimulation can be assessed on this basis. During the stimulation, however, the response of the antagonist diminishes significantly. To achieve a slow, damped and monitored movement of the stimulated limb, the influence of the antagonist is therefore also determined and taken into account iteratively or adaptively in the closed loop during the stimulation.
The device according to the invention and the method according to the invention preferably comprise a safety system. This safety system prevents the stimulation from taking place in an unintended way. FIG. 6 shows that this safety system has, inter alia, two pushbuttons. The patient keeps the first pushbutton pressed down during the stimulation. This makes it possible for the patient to end the stimulation as quickly as possible. The second pushbutton is a foot-operated pushbutton, with which the presence of a supervisor is ensured.
Either when the patient or the supervisor interrupts the pressing down of the pushbutton, no stimulation can take place in this time.
It can also be seen in FIG. 6 that the open-loop control unit of the stimulator preferably communicates with the stimulator via a non-conducting connection, in this case an infrared connection. Consequently, an electrical connection between the operator, the patient and the stimulation unit is prevented. This is particularly advantageous if an electrical connection between the patient and earth is to be prevented, which is advisable with regard to the currents possibly induced by the magnetic fields of the coils in the patient or the patient's direct surroundings, for instance the treatment chair. This is important in particular in the case of a defectively functioning coil.
In addition to these safety devices, a number of monitoring mechanisms also ensure stimulation of the patient as planned. For example, a timer function, which is in connection with the individual stimulators, prevents more than one stimulator ever being in operation at the same time. This can prevent the mutual effect of coils on one another, which could lead to unwanted transmissions of force to the patient and consequently to the patient being physically harmed.
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The invention relates to a relates to a device for stimulating a body part. According to the invention, the device comprises at least two coils S i having at least one power supply for generating the magnetic fields at innervation zones of the body part, especially at end branchings of motor nerve fibers or peripheral nerves. The invention also relates to a device for controlling or regulating the at least one power supply provided for the coils S i . The device for controlling or regulating the at least one power supply provided for the coils S i comprises at least one current pulse generator for emitting current pulses I(S i ) with pulse frequencies f(I(S i )) and pulse durations d(I(S i )) by the at least one power supply provided for the coils S i . The emission of the current pulses I(S i ) causes the muscles of the body part to contract or relax in a coordinated manner so that a coordinated composed movement of the body part ensues.
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BACKGROUND OF THE INVENTION
This invention relates generally to the art of clasps for climbing ropes, particularly to a carabiner for use by mountain climbers.
A carabiner is an oblong clasp usually used to connect a piston or link to a climbing rope in a way that allows relative sliding movement between the two. Carabiners may also be used to interconnect various pieces of climbing hardware.
The standard carabiner is an eliptical or D-shaped device formed from round aluminum or steel stock and having on one side a gate that can pivot inwardly, that is, toward the other side of the carabiner to admit a rope or strap. The standard carabiner lies substantially within a single plane, which requires that the bights or loops joined by the carabiner also be substantially coplanar.
In some instances coplanarity is not desired and in fact undesirable twisting of certain members could be avoided were opposite ends of the carabiner to be in approximately perpendicular planes rather than parallel ones. A particular instance is where the carabiner is connected between a piton attached to a wall, and a pulley. Current practice in such situations is to use two standard carabiners in series.
Accordingly, it is an object of this invention to provide climbers with a simple and inexpensive carabiner whose opposite ends lie in different planes.
An additional object of the invention is to provide such a carabiner with a gate whose orientation avoids interference between the gate and the opposite side of the carabiner, while nevertheless being properly oriented to prevent inadvertant disengagement of a rope from the carabiner. A related object is to enable the climber to install the clasp and then invert it while clipping into the devices so as to place the gate in a safe position against his body, thus preventing inadvertent gate opening.
SUMMARY OF THE INVENTION
A carabiner comprising a unitary body including a substantially straight back portion having a longitudinal axis, a pair of curved end portions extending from opposite ends of the back portion, each of said end portions comprising a proximal segment lying in a respective plane, the planes of the opposite proximal segments being substantially perpendicular to one another, and a distal segment bent out of the plane of its adjacent proximal segment and terminating at a tip substantially aligned with the tip of the opposite end portion along an axis that is skewed relative to the axis of the back portion, and further comprising a gate hinged to a first one of said tips, so as to be movable between open and closesd positions, and having means for engaging the second of said tips, to form a closed loop.
BRIEF DESCRIPTION OF THE DRAWINGS
In the accompanying drawings:
FIG. 1 is a front elevation of a carabiner embodying the invention, taken along a line perpendicular to the plane of the lower end section thereof;
FIG. 2 is a left side elevation thereof;
FIG. 3 is a plan view thereof; and
FIG. 4 is an enlarged sectional view taken along the plane 4--4 in FIG. 2.
DESCRIPTION OF THE PREFERRED EMBODIMENT
With reference to FIGS. 1 and 2, the invention is embodied in a carabiner comprising a high-strength rigid body 10 formed from round metal stock. The body includes a substantially straight back portion 12 extending between arcuate upper and lower end portions 14 and 16 each comprising a proximal segment 18 adjacent the straight portion and a distal segment 20 more remote therefrom. Each proximal segment 18 follows a simple curve lying in a plane substantially perpendicular to the plane of the opposite proximal segment. This relationship is best seen in FIG. 3, where the planes of the proximal segments of the upper and lower ends are labelled A--A and B--B respectively. Each distal segment 20 is bent out of the plane of the adjacent proximal segment toward the opposite distal segment in such a way that their two tips 22, 22' are substantially aligned with one another along an axis C--C that is skewed with respect to the axis D--D of the back portion.
Each tip 22, 22' has lateral flats 24 on opposite sides thereof, as shown in FIG. 2.
A generally cylindrical gate 26 is pivotally supported on the tip 22 by a hinge pin 28, whose ends pass through aligned holes 30 in one end of the gate, the pin being pressed through a hole 32 in the tip 22. The gate is movable between a closed position shown in FIG. 1, and an open position, shown in phantom. The gate is biased toward either of these positions (away from a half-open position) by an over-center linkage comprising a pawl or spade 34 confined within a blind bore 36 that extends along the axis of the gate. A compression coil spring 38 biases the pawl outwardly, and its free end engages within a notch 40 cut out of the tip 22. The free end of the gate has a central slot 42 similar to the slot at the opposite end; a pin 44 is pressed through holes 46 at the end of the gate.
The lower tip 22', generally similar in shape to the head tip 22, has a slot 48 that open laterally toward the open position of the gate, in a position corresponding to that of the pin 44. The pin bottoms in the slot 48 when the gate is closed.
The carabiner may be used to interconnect various ropes, straps (e.g., seat harnesses), descenders (e.g., figure eights, stitch plates, etc.) or protection devices (e.g. pitons, anchor bolts, etc.). Referring to such items generically as "devices", the preferred method of use is as follows.
With his right hand, the climber grasps the carabiner, oriented, as the climber sees it, as in FIG. 1. With the back portion 12 in his palm, he opens the gate by moving it to the right with his thumb, then hooks the upper end 14 into the upper device. Now he closes the gate, and rotates the carabiner counterclockwise, as he sees it, until the end 14 is at the bottom. Now, reopening the gate, he hooks into the lower device. If the lower device is a seat harness, the gate remains near the climber's body, insuring that the gate will not be snagged or otherwise opened accidentally. If the upper device is a piton affixed to a rock wall, the gate remains on the side away from the wall, so that the gate is accessible. The carabiner tends to orient the loops of the devices to which it is attached at right angles, obviating the need to use a pair of carabiners.
It should be noted that the carabiner described above is adapted for right-hand use, and that mirror-image carabiners will be produced for left-handers.
Inasmuch as the invention is subject to various modifications it is intended that the foregoing description and accompanying drawings shall be interpreted as only illustrative of the invention, whose full scope is to be measured by the following claims.
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A twisted carabiner comprises substantially straight back section with arcuate ends lying in substantially perpendicular planes and a gate extending between the ends so as to enable one to interconnect devices lying in different planes.
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BACKGROUND OF THE INVENTION
This present invention relates to formwork elements for building purposes and in particular relates to improved interlocking formwork elements of hollow block configuration produced from a hard foam resin material, and adapted to be filled with concrete to provide a rigid wall or the like having high insulating properties.
Elements of this general type are known for forming a hollow wall permanent formwork adapted to be filled with concrete. With these known elements the transverse walls of the blocks are of equal height to the side walls and cross binding of the filled concrete between adjacent blocks is not possible, resulting in a considerable weakening of the concrete wall. In addition the use of horizontal steel reinforcement is not possible and if the transverse members are located inwardly of the ends of the blocks to allow for cross binding of the concrete, special elements are required to enable a corner connection to be made.
SUMMARY OF THE INVENTION
It has been discovered, according to the present invention, that a vastly improved building formwork element is achieved through the use of lightweight insulating material comprising a hollow block member having side walls and end walls with mating grooves and tongues along the upper and lower edges of the side walls for interlocking purposes, said end walls having upper and lower cut-out portions receiving removable inserts to close off said end walls at corner, wall end and T-connections.
The inserts are preferably of tongue and groove form for interlocking purposes with mating tongues and grooves in said cut-out portions.
It has further been discovered, according to the present invention, that the building formwork element is further improved if there is provided transverse cross pieces in the block between the end walls, said transverse cross pieces also having upper and lower cut-out portions adapted to receive removable inserts.
It has additionally been discovered, according to the present invention, that the improved building formwork element is enhanced if it is manufactured from a hard foamed resin material such as polystyrol or the like.
It is therefore an object of the present invention to provide an improved formwork block for construction purposes having end transverse walls allowing strong cross binding of the concrete, and eliminating the requirement for special elements for the interlocking of corner connections, T-connections, wall connections and wall end closures.
It is a further object of the present invention to provide an improved formwork block for construction purposes wherein the block further contains transverse cross pieces between the end walls of the block for the dual purposes of strengthening the block and enabling a worker to cut the block into shorter fewer cavity blocks.
It is an additional object of the present invention to provide an improved formwork block which eliminates the necessity of using a number of different size and shape blocks for building formwork and permits a single size and shape building formwork block to be used for providing all wall connections, T-connections, corner connections and wall end closures, and further allowing the installation of vertical and horizontal steel reinforcement in the construction of a buliding.
Further novel features and other objects of the present invention will become apparent from the following detailed description, discussion and the appended claims, taken in conjunction with the drawings.
DRAWING SUMMARY
Referring particularly to the drawings for the purposes of illustration only and not limitation there is illustrated:
FIG. 1 is a perspective view of one embodiment of the Improved Building Formwork Block of the present invention.
FIG. 2 is a perspective view of an insert for the upper part of an end wall of the present invention.
FIG. 3 is a perspective view of an insert for the lower part of an end wall of the present invention.
FIG. 4 is a perspective view of a corner connection in a formwork wall illustrating the use of the Improved Building Formwork Block, and the inserts in the upper and lower part of the end wall.
FIG. 5 is a perspective view of a second embodiment of the Improved Building Formwork Block of the present invention.
FIG. 6 is a top plan view of the embodiment of the Improved Building Formwork Block illustrated in FIG. 5.
FIG. 7 is a cross-sectional view of the Improved Building Formwork Block taken along line 7--7 of FIG. 6.
FIG. 8 is a cross-sectional view of the Improved Building Formwork Block taken along line 8--8 of FIG. 6.
FIG. 9 is a perspective view from one side of an insert for the upper part of an end wall for the embodiment of the Improved Building Formwork Block illustrated in FIG. 5 and 6.
FIG. 10 is a perspective view from the opposite side of the insert for the upper part of an end wall for the embodiment of the Improved Building Formwork Block illustrated in FIG. 5 and 6.
FIG. 11 is a perspective view from one side of an insert for the lower part of an end wall for the embodiment of the Improved Building Formwork Block illustrated in FIGS. 5 and 6.
FIG. 12 is a perspective view from the opposite side of the insert for the lower part of an end wall for the embodiment of the Improved Building Formwork Block illustrated in FIG. 5 and 6.
FIG. 13 is a top plan view of a curved corner element or block for use in the Improved Building Formwork Block illustrated in FIG. 5 and 6.
FIG. 14 is a top plan view of a lintel element or block for use with the Improved Building Formwork Block illustrated in FIG. 5 and 6.
FIG. 15 is an end view of a lintel element or block for use with the Improved Building Formwork Block illustrated in FIG. 5 and 6.
FIG. 16 is a top plan view of a ceiling edge element or block for use with the Improved Building Formwork Block illustrated in FIG. 5 and 6.
FIG. 17 is an end view of a ceiling edge element or block for use with the Improved Building Formwork Block illustrated in FIG. 5 and 6.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
With reference to the drawings of the invention in detail and more particularly to FIG. 1, there is illustrated one embodiment of the Improved Building Formwork Block of the present invention. The form element or block of FIG. 1 comprises side walls 1 and 2, each provided at the top thereof with longitudinal ridge bearers 5 and 6, corresponding cross ridge bearers 18, 19, 20 and 21 matching longitudinal mortised key seats 7 and 8, and corresponding cross mortises 10, 11, 12, 23, 24, 25 and 26.
Side walls 1 and 2 are joined at their ends by connecting members 13 provided at their upper edge with an upstanding ridge member 14 a tongue and groove at said upper edge which corresponds with the tongue and groove 15, 17 of an insert illustrated in FIG. 2 which when inserted into the butt end of the block provides a continuous and interlocking corner and end connection with cross ridge bearers 18, 19, 20 and 21 at the top.
The other insert illustrated in FIG. 3 is provided with a groove 22, which on insertion into the butt end of the form element, provides a continuous and interlocking corner and end connection with cross mortises 23, 24, 25 and 26 at the bottom.
The inner and outer surfaces of side walls 1 and 2 and provided with vertical grooves 27 which allow for accurate cutting of the block into quarter pieces.
There is shown in FIG. 4 a perspective view of a corner connection in a formwork wall illustrating the use of the Improved Building Formwork Block of FIG. 1 and the inserts in the upper and lower parts of the end wall illustrated in FIGS. 2 and 3 respectively as part of the structure of a building.
With reference to the drawings of the invention in detail and more particularly to FIG. 5, there is illustrated a second embodiment 101 of the Improved Building Formwork Block of the present invention. The form element 101 illustrated is a multi-cavity element having side walls 102 and 103, end walls 104 and 105 and transverse walls 106 located between the end walls. End walls 104 and 105 have cut-out portions 107 and 108 and include insert members 109 and 110 removably located in said cut-out portions. Transverse walls 106 are thicker than end walls 104 and 105 and take the form of two end walls moulded back to back for reasons and for the purpose hereinafter described.
Referring to FIGS. 5 and 7, in order that elements 101 can be assembled in interlocking form, top and bottom, the side walls 102 and 103 are provided at their upper end with continuous longitudinal ridge 111 which mates with continuous longitudinal slot 112 on the underside of the walls and slots 113, 114 and 115 on the upper end mate with tongues 116, 117 and 118.
Referring to FIGS. 5 through 8, in order that elements 101 can be assembled in interlocking form, top and bottom, the side walls 102 and 103 are provided at their upper end with continuous longitudinal ridge 111 which mates with continuous longitudinal slot 112 on the underside of the walls and slots 113, 114 and 115 on the upper end mate with tongues 116, 117 and 118.
Referring to FIGS. 5 through 8, in order to locate and match the elements 101 in end to end relationship, end wall 104 is provided with vertical grooves 119 and vertical ribs 120 mating with corresponding grooves and ribs in wall 105. For end to side location of the elements, ribs 120 mate with grooves 121 in side walls 102 and 103.
The upper end wall insert 122 illustrated in FIGS. 9 and 10 is provided with vertical slots 123 and transverse slot 124 mating with vertical ribs 125 and horizontal transverse rib 126 respectively in the end walls 104 and 105.
The lower end wall insert 127 illustrated in FIGS. 11 and 12 is provided with vertical slots 128 and transverse rib 129 mating with vertical ribs 130 and groove 131 respectively in the end walls 104 and 105.
Both inserts 122 and 127 are provided with ribs and grooves to line up with the ribs 120 and grooves 119 on the end walls. Upper insert 122 is provided with a transverse rib 132 and longitudinal ribs 133 for interlocking with transverse grooves 134 and longitudinal grooves 135 in lower insert 127 when the elements are interlocked in top and bottom fashion.
For cross or T-connections with one element above another, transverse grooves 136 extending across the bottom edge of side walls are adapted to engage over ridges 111 and rib 132 of insert 122. Slots 112 and grooves 135 are adapted to engage over projections 137 at the upper edge of side walls 102 and 103.
As will be seen from FIGS. 5 and 8, the transverse walls 106 are provided, in duplicate, with similar ribs and grooves as in the end walls for receiving the upper and lower inserts.
By providing the transverse walls 106 in the configuration shown, if for example a three cavity element is required, the element can be cut or sawn through the middle of a transverse wall and the half of the cut transverse wall left on the three cavity element constitutes an end wall similar to end walls 104 and 105. Similarly with the single cavity element left after cutting. Grooves 138 are provided in the side walls 102 and 103 as a guide for cutting the elements. Grooves 139 are also provided on the side walls as a guide if the element is to be cut to provide an open ended half cavity at one end thereof.
In use, in the construction of a building, the elements or blocks of the invention are set out on a concrete slab foundation preferably to 3 course or row height will all elements interlocking or abutting to delineate rooms, doors, windows, vents and the like. Concrete is then poured into the elements or blocks and allowed to set and further elements are added and filled until total room height has been reached. It is preferable to insert vertical reinforcing rods into the concrete slab so as to extend through the cavities of the elements and horizontal reinfrocing rods can be conveniently located in grooves 140 in the end and transverse walls and tied to the vertical reinforcing rods.
In order to allow for a good crossbinding of the concrete fill along the walls, the inserts 122 and 127 are removed and this also allows use of extended lengths of horizontal reinforcement. The inserts 122 and 127 must be used at corners or wall ends or in some cases at butt joints, to provide a full wall surface and of course to prevent the concrete running out. Preferably a filling rail should be located over the top of the elements on each side to prevent the concrete entering the grooves and slots on the top of the elements. This will make the placing of subsequent elements much easier.
Large diameter pipes for plumbing and carrying electrical cables may be located in the elements before filling, and being fully embedded in the concrete a soundproofing effect is obtained. Small diameter pipes can be set into the sides of the elements by cutting a groove therein such as by using a soldering gun hot wire bent to U-shape. This is most advantageous with hot water pipes in view of the excellent insulation properties of the material of the elements.
The outside surfaces of the walls formed can be faced with bricks, cement rendering or plaster reinforced with fibre glass. Bricks can be laid directly on to the elements as the non-capilliary and high insulation properties of the elements obviates the requirement of a cavity between brick and wall. Brick ties can be pushed into the elements just after filling.
The inside surfaces may be faced with plaster board, tiles, timber panelling and the like.
By providing walls of the material of the elements, most effective insulation properties are obtained. Equally there is exceptional soundproofing. The preferred material, polystyrol, is a non-combustable and self extinguishing material.
Referring to FIG. 13 there is illustrated an element or block for use on curved corners or doorways of buildings. The element or block of this embodiment has similar constructional and interlocking features as the element or block of FIGS. 5 to 12. The curved outer surface of this element or block is provided with a number cutting guide grooves so that a curved part having less than 90° can be obtained.
FIGS. 14 and 15 illustrate another embodiment of the invention wherein the element or block comprises a lintel member having the upper and side parts of the side members similar in form to the element or block of FIGS. 5 to 12, but including a closed bottom 141 and dovetail shaped ribs 142, to enhance locking of the concrete therein, and no transverse walls. In use this lintel member is set across a door opening on top of existing wall elements and supported while being filled with concrete. The lintel element is dimensioned so that further courses or levels of the basic formwork elements can be added thereto and interlocked by reason of the mating configuration of the upper edge of the lintel side member.
FIGS. 16 and 17 illustrate a ceiling edge element or block 143 which is used at room height level to support a concrete plate or plates forming a ceiling. The side wall 144 is of similar configuration to the element or block of FIGS. 5 to 12 as is the top edge of side wall 144, the lower part 145, and the bottom part 146 has grooves and ribs to allow interlocking with a basic element. The bottom part 146 has cavities 147 and 148 which are filled with concrete. In use this ceiling edge element or block is interlocked on the walls constituted by the basic elements of FIGS. 5 to 12 and after the concrete filling has set, the ceiling plate or plates is or are placed in position resting on the ledge afforded by element 143. Support members are located throughout the area of the ceiling plates and a further concrete fill is made up to the top of side wall 144. Reinforcement members can be inserted in the concrete fill.
After the concrete fill has set, further floors of the building can be developed in like manner to the first floor and the basic formwork elements can be interlocked and be built up from the side wall 144 of the ceiling edge member and the concrete fill therein.
As shown in FIG. 16 grooves 149 are formed in the element as a guide to cutting, the diagonal grooves allowing for accurate cutting of mitred ends of the element.
The elements or blocks as defined in FIGS. 1 through 16 are used to build structures such as a commercial or residential building.
Of course, the present invention is not intended to be restricted to any particular form or arrangement, or any specific embodiment disclosed herein, or any specific use, since the same may be modified in various particulars or relations without departing from the spirit or scope of the claimed invention hereinabove shown and described of which the apparatus shown in intended only for illustration and for disclosure of an operative embodiment, and not to show all of the various forms of modification in which the invention might be embodied.
The invention has been described in considerable detail in order to comply with the patent laws by providing a full public disclosure of at least one of its forms. However, such detailed description is not intended in any way to limit the broad features or principles of the invention, or the scope of patent monopoly to be granted.
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Improved formwork elements for building purposes. The present invention relates in particular to improved interlocking formwork elements of hollow block configuration produced from a hard foam resin material, and adapted to be filled with concrete to provide a rigid wall or the like having high insulating properties.
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RELATED APPLICATIONS
This application is a Continuation of application Ser. No. 11/433,584, filed May 15, 2006, which is a Divisional of application Ser. No. 10/342,236, filed Jan. 15, 2003, now U.S. Pat. No. 7,070,588 B2, which is a Divisional of application Ser. No. 09/758,129, filed Jan. 12, 2001, now U.S. Pat. No. 6,530,912 B2, both of which are incorporated herein in their entirety by reference thereto.
FIELD OF THE INVENTION
The present invention relates to the transport of perishable therapeutics from a storage reservoir to a target site. More specifically the present invention relates to method and apparatus for effectively connecting a reservoir of perishable therapeutic to a lumen that is lined with a material compatible with the perishable therapeutic.
BACKGROUND OF THE INVENTION
The delivery of therapeutics to a target site in the body of a patient is a task that finds innumerable applications in the practice of modern medicine. In some applications the therapeutic may be delivered through a needle and syringe while in others the therapeutic may be delivered though a pump and catheter system. In either of these configurations, as with the many other plausible configurations, the objective is to deliver active therapeutic to a target site such that the therapeutic may cure the infirmities resident at the target site. For some perishable, sensitive or volatile therapeutics, such as certain viruses employed today, a compatibility issue can arise between the therapeutic and the channel or vessel that will transport the therapeutic from its storage vessel to its target site. When compatibility issues do arise between the therapeutic and its surroundings, the therapeutic may lose some or all of its effectiveness and may, upon its arrival at the target site, be partially or completely inert. In certain applications, the therapeutic may lose its effectiveness moments before it is delivered as it passes down and through the delivery lumen of the delivery device simply because the therapeutic has come in contact with a non-compatible material.
Therefore, the environment in which the therapeutic is stored as well as the environment in which the therapeutic must travel can and does affect the potency and effectiveness of certain perishable therapeutics. In order to avoid the risk of deterioration of the potency of perishable therapeutics it is, consequently, advantageous to minimize or eliminate the contact between non-compatible materials and the therapeutic during the delivery of the therapeutic to the target site.
SUMMARY OF THE INVENTION
The present invention includes the proper handling of perishable therapeutic. In one embodiment a system for connecting a reservoir of perishable therapeutic with a lumen is provided. This embodiment has a hollow hub having a first end and a second end. The first end of the hollow hub, which contains a bond port, is in fluid communication with the second end of the hollow hub. The second end of the hollow hub in this embodiment may contain a docking groove that is sized to couple a reservoir to it. This embodiment also includes an inner hypo-tube having a proximal tip and an inner lumen. The inner lumen may be lined with a perishable therapeutic compatible lining and may be in fluid communication with the second end of the hub through the proximal tip of the inner hypo-tube. The inner lining and the proximal tip may be configured to shield perishable therapeutic, ejected from the reservoir and present within the second end, from materials that are non-compatible with the therapeutic.
In a second embodiment a method for coupling a reservoir of perishable therapeutic to a lumen lined with a therapeutic compatible lining is provided. This method includes inserting the proximal end of a manifold hypo-tube into a first end of a hub, the hub also having a second end; placing the proximal end of an inner hypo-tube within the proximal end of the manifold hypo-tube and urging the proximal end of the inner hypo-tube through the proximal end of the manifold hypo-tube until the proximal end of the inner hypo-tube comes in contact with a stopping point in the hub. In this second embodiment the tip of the proximal end of the inner hypo-tube may be covered in a therapeutic compatible material and the inner surface of the inner hypo-tube may be covered with a therapeutic compatible lining.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side sectional view of the proximal end of a concentric hypo-tube assembly employed in an embodiment of the present invention.
FIG. 2 is a cross-sectional view taken along line 2 - 2 of FIG. 1 .
FIG. 3 is a cross-sectional view taken along line 3 - 3 of FIG. 1 .
FIG. 4 is a side sectional view of the proximal end of a concentric hypo-tube assembly in accordance with an alternative embodiment of the present invention.
FIG. 5 is a side sectional view of the proximal end of a concentric hypo-tube assembly in accordance with another alternative embodiment of the present invention.
FIG. 6 is an enlarged sectional view of the proximal end of the concentric hypo-tube assembly as employed in the embodiment illustrated in FIG. 5 .
DETAILED DESCRIPTION
As described and used herein a “perishable therapeutic” includes a therapeutic whose efficiency can be diminished through the contact with specific non-compatible compounds or materials. These perishable therapeutics include adenoviral vectors; adeno-associated vectors; certain proteins including basic fibroblast growth factors; certain nucleic acids such as DNA plasmid; and, certain cells such as myoblasts, fibroblasts, and stem cells. Thus, regarding these examples, when these perishable therapeutics come in contact with stainless steel, for example, they lose some or all of their effectiveness as a therapeutic. This list of perishable therapeutics is not exhaustive but, instead, is meant to be exemplary of therapeutics that may lose some or all of their healing effectiveness once placed in proximity to a specific non-compatible material.
As described and used herein a “perishable therapeutic compatible lining” includes a lining that does not substantially retard the effectiveness of an otherwise perishable therapeutic. It may include a specific coating applied to a material as well as a separate material that is later adhered or placed adjacent to the underlying material that it lines. One primary purpose of this lining is to retard the degradation of therapeutic that comes in contact with it. While the lining may modify the effectiveness of the therapeutic it does so at a lesser rate than that of the material that it covers and would otherwise come in contact with the therapeutic.
As described and used herein “non-compatible” is an adjective used to describe materials that more than insubstantially affect the potency or effectiveness of a therapeutic. When quantified this may include materials that reduce a therapeutic's efficiency by approximately 10% through and including an entire 100% reduction in its effectiveness, thereby making the use of the therapeutic, after coming in contact with the non-compatible material, an inconsequential event.
FIG. 1 is a side sectional view of a concentric hypo-tube assembly 150 and hub 10 in accordance with one embodiment of the present invention. In FIG. 1 the hub 10 and the proximal end of the concentric hypo-tube assembly 150 are clearly evident. As can be seen the hub 10 may be shaped in the form of an hour-glass with a longer end 130 connected to a female luer connection 110 through a channel 145 having a stopping point 120 . The hub 10 in FIG. 1 contains a hub wall 11 which may be manufactured from a single material such as a polypropylene, a polycarbonate or any other material that is rigid and compatible with the perishable therapeutics that may be delivered by the hypo-tube assembly 150 . Alternatively, should this material not be compatible with the therapeutic it may be lined with a material that is.
As can be seen, the female luer connection 110 contains threads or grooves 12 , which are illustrated in FIG. 1 as angled dashed lines encircling the interior surface of the female luer connection 110 . These grooves 12 and the female luer connection 110 may be dimensioned so as to accept and secure a removable reservoir (which is not shown) containing perishable therapeutic. This perishable therapeutic may be injected down through the concentric hypo-tube assembly 150 to a target site within the body by depressing a syringe (not shown) integrated with the removable reservoir. As can be seen, a threaded reservoir containing the therapeutic may be readily attached to the female luer connection 110 by aligning and screwing the reservoir into the connection 110 .
As is evident the proximal end of a manifold hypo-tube 17 and the proximal end of an inner hypo-tube 18 are located within the longer end 130 of the hub 10 . The manifold hypo-tube 17 and the inner hypo-tube 18 may be designed for numerous medical applications. They may be designed to be part of an injection catheter used to inject perishable therapeutic into the heart or other dense tissue area of a patient. They may also be designed to be implanted in the body and used for long-term delivery of a therapeutic. When used for puncturing applications the hypo-tubes may be made from stainless steel or other suitably rigid materials. Conversely, when used in less stress-intensive applications the hypo-tubes may be made from less rigid materials such as plastic.
In this particular embodiment the manifold hypo-tube 17 is made from stainless steel and is attached to a spring mechanism of an injection catheter (not shown) which is used to inject a needle into the heart or cardiopulmonary sac of a patient. Once the needle is injected into the heart or cardiopulmonary sac the inner hypo-tube 18 , also stainless steel, would be used to carry therapeutic to the targeted site of the body.
In this embodiment the inner hypo-tube 18 contains a liner 104 , which may be made from polyether block-amide (one example of which is Pebax™ 5533) or any other material that is compatible with a perishable therapeutic that may contact the liner 104 . The proximal end of the inner hypo-tube 18 in this embodiment has a collar 19 adjacent to it. This collar 19 may be made from the same material as the liner or it may be made from another material as long as the second material is also compatible with the perishable therapeutic that may come in contact with it. The collar 19 , made from a therapeutically compatible material, may be sized to compressibly secure or press-fit itself to the stopping point 120 located within the channel 145 of the hub 10 . In this embodiment the liner 104 extends out of the inner hypo-tube and through the collar 19 to line the interior lumen of the collar. Therefore, when the inner hypo-tube is being manufactured the liner 104 may be protruding from the proximal end of the hypo-tube and may be covered by or threaded through the collar such that the liner 104 lines the interior lumen of the collar.
In this embodiment the inside diameter of the lumen in the inner hypo-tube 18 may be about 0.0130 inches and the outside diameter of the inner hypo-tube 18 may be about 0.0250 inches. The inside diameter of the liner 104 may be 0.0075 inches. Other sizes and dimensions are also possible.
The stopping point 120 of the hub 10 in this embodiment is sized such that it may snugly secure the collar 19 to the hub 10 after the collar 19 has been pushed or urged toward the stopping point 120 . In other words, the use of friction and the proper sizing of the dimensions between the stopping point 120 and the collar 19 create a mechanical adhesion or press-fit that couples the collar 19 to the hub 10 at the stopping point 120 and prevents over-wicking of adhesive 102 .
The hub wall 11 also contains a plurality of bond ports. In this figure a first bond port 14 is shown in the channel 145 of the hub 10 while a second bond port 15 is shown on the longer end 130 of the hub 10 . These bond ports may have a funnel-like configuration and may provide an access via from outside the hub to inside the hub to allow adhesive or other material to be injected from outside the hub 10 at different points along the hub 10 .
In FIG. 1 an adhesive 102 is shown after being injected into the hub 10 through the first bond port 14 and the second bond port 15 to secure the inner hypo-tube 18 and the manifold hypo-tube 17 to each other and to the hub 10 . As is evident the adhesive 102 surrounds the proximal end of the inner hypo-tube 18 as well as the proximal end of the manifold hypo-tube 17 but has not wicked past the stopping point 120 between the collar 19 and the hub 10 . In practice it is preferred that the amount of adhesive injected into the hub is controlled such that no adhesive wicks past the stopping point 120 and, consequently, risks coming in contact with therapeutic that may be injected down the lumen of the inner hypo-tube. The adhesive employed in this embodiment may be H.B. Fuller adhesive no. 3507 and Tra-con FDA2.
Other features of the hub 10 illustrated in FIG. 1 are the reinforcing nub 16 and the wing 13 . These two components extend from the tubular hourglass-designed hub 10 and allow the hub 10 to be grasped and rotated as required. For example, when a threaded reservoir of therapeutic needs to be screwed or coupled into the female luer connection 110 of the hub 10 , the wings 13 can be grasped by an operator and used to rotate the hub 10 to couple the hub 10 to the therapeutic reservoir (not shown).
In manufacturing the device illustrated in FIG. 1 , a manufacturer may first gather the components to be assembled. These components would include the inner hypo-tube 18 , the manifold hypo-tube 17 , and the hub 10 . As a first step the manufacturer may insert the proximal or near end of the manifold hypo-tube 17 into the longer end 130 of the hub 10 . The proximal end of the manifold hypo-tube 17 may be completely inserted into the longer end 130 of the hub 10 until it touches an interior hub 10 wall or, alternatively, until it is located near an interior hub 10 wall. Whether or not the proximal end of the manifold hypo-tube touches an interior wall may be determined by the placement of the bond ports because adhesive injected through the bond ports may be obstructed from reaching the interior surfaces of the manifold hypo-tube if the placement of the manifold hypo-tube 17 , within the hub 10 , obstructs the bond ports. While the distance that the proximal end of the manifold hypo-tube 17 may be inserted into the hub 10 can vary, it is preferred that the proximal end of the manifold hypo-tube 17 does not touch an interior hub wall 11 so that adhesive injected into the second bond port 15 may flow both inside and outside of the manifold hypo-tube 17 . Should the manifold hypo-tube 17 come in contact with the hub wall, adhesive injected through the second bond port 15 may be deterred from traveling completely in and around the proximal end of the manifold hypo-tube 17 . Once the proximal end of the manifold hypo-tube 17 is inserted into the hub 10 , the proximal or near end of the inner hypo-tube 18 , may be placed within the manifold hypo-tube 17 and into the hub 10 .
As can be seen in FIG. 1 the proximal end of the inner hypo-tube has a collar 19 adjacent to its tip. This collar may be manufactured from the same material as the liner or any other material compatible with the perishable therapeutic that may be delivered by the device. The collar may be manufactured by extending the lining material, which lines the inner lumen of the inner hypo-tube 18 , 0.500 inches past the tip of the inner hypo-tube 18 and, then, by building or wrapping the collar material around the protruding lining material such that, upon completion, the collar is connected to the lumen material and contains an inner lumen of lining material seamlessly connected to the inner hypo-tube. Care should be taken when manufacturing the collar to avoid collapsing the lumen within the liner. Once the collar is manufactured, it should preferably be allowed to cure for 12 hours before it is trimmed. Care should also be taken here, as with the other portions of the assembly process, not to kink, force or otherwise twist the various components. In addition, an assembler should continually verify that no adhesive has entered or has otherwise come in contact with the lumen 101 of the liner 104 .
The inner hypo-tube 18 along with collar 19 may then be completely inserted into the hub 10 until the collar 19 comes in contact with the stopping point 120 located within the channel 145 of the hub 10 . Once the collar 19 reaches the stopping point 120 , an additional axial force may be placed on the inner hypo-tube 18 to further urge or press-fit the collar 19 into the stopping point 120 . The collar 19 , which may be made from Pebax™ 5533, may be soft and compressible so that it readily deforms under the additional axial load and securely contacts the stopping point 120 to provide a holding force to retain the collar 19 against the stopping point 120 .
After the hypo-tubes have been inserted and properly positioned within the longer end 130 of the hub 10 adhesive may be injected into the bond ports. Adhesive may first be injected into the first bond port 14 such that it surrounds the proximal end of the inner hypo-tube 18 and the collar 19 and the adhesive may then be injected into the second bond port to surround the proximal end of the manifold hypo-tube 17 . The adhesive injected in the first bond port may cement and lock the inner hypo-tube 18 to the hub 10 and the collar 19 to the tip of the inner hypo-tube 18 . It may also provide a bulwark for preventing the unwanted seepage of therapeutic past the collar 19 and down into the larger end 130 of the hub 10 . The adhesive may be manufactured by mixing the components by hand for a minimum of 2 minutes to ensure that there is a consistent color in the adhesive. It may then be delivered by placing it in a syringe for injection through the bond ports into the hub.
After adhesive is injected into the first bond port 14 it may be injected into the second bond port 15 to further secure the hypo-tubes to themselves and to the surrounding hub. Excessive adhesive should be removed from the surface of the hub. After the adhesive is allowed to cure, for preferably 12 hours, a 30× microscope may be used to verify a 1 mm bond length between the inner hypo-tube 18 and the hub 10 and between the outer hypo-tube 17 and the hub 10 .
FIG. 2 is a cross-sectional view taken along line 2 - 2 of FIG. 1 that illustrates the liner 104 , the hub wall 11 , the liner lumen 101 , the manifold hypo-tube 17 , and the inner hypo-tube 18 . As can be seen, FIG. 2 illustrates that the longer end 130 of the hub 10 as well as the various lumens and hypo-tubes each have a circular cross-section and that they may be concentrically located about one another. While concentric circular cross-sections are shown in this embodiment other configurations and cross-sections may also be employed. For example, these cross-sections may also be hexagonal, square, and any other cross-section required by the specific application. Moreover, they may not be equally spaced about the same axis but may, instead, be located at different distances from a reference longitudinal axis.
In FIG. 2 the liner 104 is shown as not being in contact with the inner hypo-tube 18 , it is preferred, however, that the liner 104 should be in contact with the inner hypo-tube 18 so that the liner 104 may receive structural support from the inside surface of the inner hypo-tube 18 and so that the lumen may have the largest cross-sectional area possible.
FIG. 3 is a sectional view of a cross-section taken along line 3 - 3 of FIG. 1 . As can be seen, the wings 13 protrude outwardly from the hub wall 11 and are aligned 180 degrees from one another. As can also be seen, the collar 19 is in direct contact with the inner surface of the hub wall 11 as well as with the liner 104 . It is through this direct contact with the inner surface of the hub that adhesive injected into the hub at bond ports 14 and 15 is prevented from wicking past and into the female luer connection 110 side of the hub 10 . Liner lumen 101 is also evident in FIG. 3 .
FIG. 4 illustrates a sectional view of an alternative embodiment of the present invention. In FIG. 4 a hub 40 and hypo-tube assembly 420 are shown. The hub 40 has a female luer connection 400 having grooves 42 as well as reinforcing nubs 46 , wings 43 , a first bond port 44 , a second bond port 45 , a hub wall 41 , and a stopping point 410 . The hypo-tube assembly 420 includes a manifold hypo-tube 47 , an inner hypo-tube 48 , a liner 404 , a liner lumen 401 , and a collar 49 adjacent to the inner hypo-tube 48 . The collar 49 has a heat shrink material 405 placed at its end. This heat shrink material 405 may be made from Teflon™ while the collar may be made from a material that is compatible with a perishable therapeutic, and the hypo-tubes may be made from stainless steel. The hub wall 41 may be homogeneously manufactured from a plastic or other sufficiently rigid material.
As is evident, the proximal end of the inner hypo-tube 48 in this embodiment has been inserted into the hub 40 . However, rather than having a silo-shaped collar, as described in the first embodiment, the collar 49 in this embodiment has been covered or otherwise treated with a Teflon™ heat shrink which acts to constrict the outer diameter of the collar and provide a flush and snug fit between the collar 49 and the stopping point 410 of the hub 40 .
In order to secure the collar 49 to the hub 40 , heat should first be applied to the tip of the collar 49 , which contains the Teflon™ heat shrink. The tip of the collar 49 containing the heat shrink will then shrink or constrict under the forces of the heat shrink to a size that closely matches the dimensions of the stopping point 410 of the hub 40 . A close dimensional alignment between the tip of the collar 49 and the stopping point 410 will provide a good sealing engagement between the collar and the hub. A benefit of a good sealing engagement is that therapeutic threaded into the female luer connection 400 and injected into the liner lumen 401 will be prevented from passing the interface point between the collar 49 and the stopping point 410 and contacting materials that are not compatible with the therapeutic. To further secure the inner hypo-tube 48 to the stopping point 410 , and the other hypo-tube assembly 420 components to the interior of the hub 40 , an adhesive should be injected into the first bond port 44 and the second bond port 45 in this embodiment.
FIG. 5 illustrates a side sectional view of another alternative embodiment of the present invention. Rather than using the collars 19 and 49 described above, the embodiment illustrated in FIG. 5 uses a flared funnel-shaped liner end 506 to facilitate the clean contact and communication between therapeutic placed in the female luer connection 500 and the lumen 501 located within the inner hypo-tube 58 .
In FIG. 5 a hub 50 and hypo-tube assembly 530 are illustrated. This hub 50 along with the hypo-tube assembly 530 are shown in sectional view consistent with the illustrations provided in FIGS. 1 and 4 above. This hub 50 contains a hub wall 51 , the hub wall 51 having a first bond port 54 , a second bond port 55 , and a third bond port 59 wherein each bond port is conically shaped and provides a passage from the exterior of the hub 50 to the interior of the hub 50 . These bond ports provide access for adhesive to be injected into the hub during the assembly of the device.
Similar to the embodiments described above, the hub wall 51 contains reinforcing nubs 56 and wings 53 . These reinforcing nubs 56 and the wings 53 are used to help grasp and secure components to the female luer connection 500 of the hub 50 . This female luer connection 500 located at one end of the hub 50 is used to connect other components to the hub 50 . This female luer connection 500 contains grooves 52 resident within the inside walls of the female luer connection 500 .
Also evident in FIG. 5 are a liner 504 , a liner lumen 501 , an inner hypo-tube 58 , and a manifold hypo-tube 57 . In this embodiment, rather than having the collar touch the stopping point of the hub 50 as in the above embodiments, the proximal end of the inner hypo-tube 58 comes in contact with the stopping point 508 of the hub 50 and the liner 501 extends past the end of the inner hypo-tube 58 into the female luer connection 500 of the hub 50 . The liner 504 extending into the female luer connection 500 in this embodiment has a liner flared end 506 located at its most proximal end and a liner rim 507 . The liner flared end 506 and liner rim 507 extend into the female luer connection 500 and rest up against the hub wall 51 . In order to secure this distended liner section to a hub wall 11 adhesive 502 may be injected behind the liner 504 through the third bond port 59 to secure the liner in place. However, when adhesive is injected into the connection it is preferred that the amount of adhesive is limited such that the adhesive does not wick past the liner rim 507 of the liner 504 and be placed at risk of contacting therapeutic that may be injected into the lumen 501 .
In use, when a source of therapeutic is secured or threaded into the female luer connection 500 , as the therapeutic is forced down into the lined lumen, the liner flared end 506 and the liner rim 507 may be pressed against the hub wall 51 , thereby contributing to a secure and tight contact point between the liner and the hub wall.
FIG. 6 is an enlarged view of the stopping point 508 of the hub 50 from FIG. 5 . As is clearly evident in this embodiment adhesive 502 has been injected and is securing the inner hypo-tube rim 508 , the liner 504 and the liner flared end 506 . As can also be seen, the adhesive 502 , while resident in, around, and between the inner hypo-tube, the hub, and the liner 504 , does not extend past the liner rim 507 . As mentioned above, it is preferable that the adhesive 502 does not extend past the liner rim 507 such that the potential contact between therapeutic and non-compatible materials such as the adhesive 502 may be minimized if not eliminated.
Target sites that may be treated by the various embodiments of the present invention include any mammalian tissue or organ, whether injected in vivo or ex vivo. Non-limiting examples include heart, lung, brain, liver, skeletal muscle, smooth muscle, kidney, bladder, intestines, stomach, pancreas, ovary, prostate, eye, tumors, cartilage and bone.
Therapeutics that may be employed in the various embodiments of the present invention include: adenoviral vectors; adeno-associated vectors; certain proteins including basic fibroblast growth factors; certain nucleic acids such as DNA plasmid; and, certain cells such as myoblasts, fibroblasts, and stems cells.
As will be understood by one of skill in the art, while various embodiments of the present invention have been presented, numerous other embodiments are also plausible. For example, rather than having the flared end of the liner protruding into the female luer connection of the hub the liner may instead wrap around and cover the inner hypo-tube rim which is then press-fit into the stopping point of the hub to form a fluid tight connection. Consequently, the disclosed embodiments are illustrative of the various ways in which the present invention may be practiced and other embodiments may be implemented by those skilled in the art without departing from the spirit and scope of the present invention.
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A system for connecting a compatibility liner with a source of perishable therapeutic is provided. In one exemplary system for connecting a reservoir of perishable therapeutic with a lumen, a hollow hub having a first end and a second end is provided. The first end of the hollow hub, which contains a bond port, is in fluid communication with the second end. The second end of the hollow hub may contain a docking groove that is sized to couple a reservoir to it. The system also includes an inner hypo-tube having a proximal tip and an inner lumen. This inner lumen is lined with a therapeutic compatible lining and is in fluid communication with the second end of the hub through the proximal tip of the inner hypo-tube. The inner lining and the proximal tip in this system are configured to shield therapeutic ejected from the reservoir from contacting materials that can diminish the integrity of the therapeutic.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to a method and an apparatus for controlling communication between a terminal and a number of chip cards.
2. Description of the Related Art
German Patent 196 35 311 A1 discloses a method for controlling communication between a terminal and a number of chip cards, in which communication is maintained within a communication range between the terminal on the one hand and the chip cards of different manufacturers or different types on the other. After the signals emitted by the terminal have been decoded in the chip card and compared with characteristic information stored in the chip card, it can be determined whether the chip card corresponds to a certain signal frequency. Thus, groups of different type chip cards can be formed whose communication with the terminal can take place without interference from cards of another type.
With the prior art, however, communication with individual cards is not addressed. The invention is addressed to the problem of devising a method of and an apparatus for controlling communication between a terminal and a number of chip cards such that secure and rapid communication is assured between the terminal and the individual chip cards.
SUMMARY OF THE INVENTION
For the solution of this problem, a method according to the invention comprises the steps of: emitting electromagnetic waves by a terminal to form a communication zone for communication between the terminal and at least one of a plurality of chip cards; transmitting an answer-to-reset by one of the plurality of chip cards; generating an identifier by the terminal corresponding to the one chip card; and storing the identifier in the terminal.
In one embodiment, the identifier may be transmitted to the one chip card and stored therein. The identifier may be transmitted in an initial part of a communication between the terminal and the one chip card. The identifier may be deleted in an end part of a communication between the terminal and the one chip card with an end command emitted by the terminal.
An apparatus according to the invention comprises a terminal generating an electromagnetic field to form a communication zone and a plurality of chip cards arranged in the communication zone of the terminal. An identifier is generated and is stored in at least one of the terminal and one chip card from the plurality of chip cards, for identification of the one chip card.
The identifier may be in the form of a terminal-specific identification word. The identifier may be stored in a RAM memory of the chip card.
A different identifier may be assigned to each of a plurality of chip cards entering the communication zone. The different identifiers are generated according to the order of entry of a chip card into the communication zone.
Identifiers for a plurality of chip cards may be stored in an identification file of a memory of the terminal. A sequence of the identifiers is in the form of a dynamic order of identification, such that a storage location of an identifier corresponding to a particular chip card is overwritten in the memory of the terminal after communication between the terminal and the chip card.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic drawing of the communication of chip cards introduced into an electromagnetic field of a terminal.
FIG. 2 is a chart of the identification procedure at the beginning of a communication between the terminal and a chip card.
FIG. 3 is a block diagram of the file structure of a chip card.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The invention has also been disclosed in related German patent application No. 198 30 526.5, filed Jul. 8, 1998, which is hereby incorporated by reference.
The advantage of the invention is to be seen especially in the fact that in the terminal an identifier is produced which in a simple manner identifies the corresponding chip card, so that communication between the terminal and the corresponding chip card can take place rapidly and securely.
The basic idea of the invention is to utilize the already existing identification of the chip card and convert it in the terminal to a communication-specific identification. In this way a kind of identification of the chip card attuned to the particular terminal can be made possible which will control the further conduct of the communication. Specific chip cards in the communication zone can be addressed and operated contactlessly while the transfer times during the progress of the communication are reduced, because when any communication sequence is transmitted between the terminal and the chip card in question, the identification is transferred with it, so that, with the increasing number of communication sequences, the saving of time in the transmission thereof is increased by the identification according to the invention.
An embodiment of the invention is further explained below with reference to the drawings.
FIG. 1 shows a terminal 1 which is configured as a card reading apparatus for wireless communication with one or more chip cards 2 . The terminal has a transmitting and receiving unit 3 which radiates electromagnetic waves to form a communication zone 4 . In the communication zone 4 the intensity of the electromagnetic waves is such that communication between the terminal 1 and a chip card 2 can begin with the emission of a reset sequence by the transmitting and receiving unit 3 . Usually the communication is started by bringing the chip card 2 into the communication zone 4 and by powering the chip card connected therewith by a power-on-reset signal from the terminal 1 .
As it can be seen in FIG. 2, an identification procedure 5 takes place immediately at the beginning of the communication. A reset sequence 6 of the terminal 1 is received by means of an antenna 7 integrated in the chip card 2 and is processed in a chip, not shown, of chip card 2 . As a response to this reset signal 6 the chip card 2 sends an answer-to-reset (ATR) 8 with an identifying serial number or the like, which has a length of several bytes. In the next step 9 the generation of the identifier takes place in the terminal, and it is preferably a code word 10 that is stored in the terminal 1 . Preferably, the code word 10 is stored in a given identification file in the memory of the terminal 1 .
The data length of the code word 10 may depend upon a number of chip cards 2 assumed to be simultaneously in the communication zone 4 ; it is preferably 1 byte long, but can be longer or shorter depending on the protocol, so that several chip cards can be provided with different code words 10 .
Then, in a step 15 , this code word 10 along with the chip card's identifying serial number is transmitted to the chip card 2 identifiable thereby, so that in a further step 16 , the code word can be stored in a RAM or EEPROM of the chip card. The transmission of the first communication sequence 17 from the terminal to the chip card 2 lastly takes place using the code word, now stored in memory in the chip card 2 . The rest of the communication sequences of the communication procedure now take place using the code word 10 assigned to the chip card 2 . If another chip card in the communication zone 4 of the terminal 1 sends a reset sequence 6 to the terminal 1 during a communication with the first chip card, then this communication with the first chip is temporarily interrupted so that the terminal 1 can send this second chip card an identifying code word 10 . The communication between the first chip card and the terminal 1 is then resumed.
The communication between the transmitter/receiver unit 3 and the chip card 2 can be continued in order, for example, to charge a predetermined amount of money for the use of a parking lot. For this purpose the transmitter/receiver unit 3 transmits a charge command 17 as part of a communication sequence which subtracts a given amount from the sum of money stored in the chip card. In a further step 18 this command is executed in the chip card and the corresponding amount is subtracted in the EEPROM of the chip card.
Next the chip card 2 transmits, in a step 19 , an answer sequence which contains the booking data concerning this payment procedure.
Optionally, provision can be made at the end of the communication procedure S for the transmitter/receiver unit 3 to emit an end command 20 with the command “delete identification word 10 ” which after being received by the chip card 2 produces in a further step 21 the deletion of the code word 10 . This prevents any unwanted repeated addressing of the chip card 2 in case another chip card coming into the communication zone 4 has received the same identification word 10 . Thus, double charging can be prevented. Alternatively, the terminal 1 , by means of a time-delay circuit or by giving out the identification words in a given sequence, can prevent any so-called collision between several chip cards.
Preferably the identification word 10 is deposited in a RAM 12 of the chip card 2 and is called up by way of a predefined memory address. Alternatively the code word 10 can also be stored in an EEPROM of the chip card 2 .
It is important in the invention that, by way of the identification word 10 , one of a plurality of chip cards 2 can be associated unmistakably with the terminal 1 and is identifiable by it, so that a secure and quick communication can be performed between the terminal 1 and the chip card 2 . After the communication is ended and the chip card 2 departs from the communication zone 4 , the code word 10 can be given to another chip card. The terminal 1 assigns to the particular chip cards an established identification sequence as dynamic identification words according to the number and order of the entry of the chip cards into the communication zone 4 .
The identifier 10 may be generated in the terminal 1 after receipt of the first sequence of each chip card 2 and temporarily stored in the terminal, and stored for as long as the communication between the terminal 1 on the one hand and the chip cards 2 on the other hand is not discontinued. Thereafter, the same identifier 10 can be used for identification during communication with other consecutively following chip cards.
After it has been generated, the identifier 10 may be transferred directly to the corresponding chip card 2 , where it is stored. This results in a considerable saving of time, since the identifier 10 is a code word that can be substantially shorter than the original serial number deposited in each chip card 2 for its identification.
The identifier 10 is preferably a code word which, in view of the small number of chip cards 2 simultaneously within the communication zone 4 , can be of short length, so that the transmission time can be substantially reduced.
At the same time, however, there must be the assurance that, after the end of the communication between the terminal 1 and a first chip card 2 , and as long as the first chip card 2 is still in the communication zone 4 , any new issuance of the same identification to another chip card 2 is prevented. Otherwise the first chip card 2 would also be addressed. This can be prevented preferably by having the terminal 1 send an end signal with a command that produces the deletion of the identifier 10 in the first card.
The identification word 10 may be stored only in a RAM memory in the chip card 2 , so that after the chip card 2 has been removed from the communication zone 4 , the identification word is automatically erased. This memory area can then be used for other purposes such as, for example, an operation of the chip card requiring contact.
The foregoing description of a preferred embodiment 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 modifications and variations are possible in light of the above teachings or may be acquired from practice of the invention. The embodiment was chosen and described in order to explain the principles of the invention and its practical application to enable one skilled in the art to utilize the invention in various embodiments and with various modification as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the claims appended hereto, and their equivalents.
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The invention relates to a method and an apparatus for controlling communication between a terminal and a number of chip cards. Electromagnetic waves are continuously emitted by the terminal to form a communication zone within which communication between the terminal and the chip cards is initiated and sustained. After the sequence emitted by a first chip card, an identifier is generated in the terminal identifying the same chip card and is stored in the terminal.
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CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of U.S. patent application Ser. No. 09/146,702 filed Sep. 3, 1998 and issued as U.S. Pat. No. 6,029,329, which is a divisional of U.S. patent application Ser. No. 08/598,148 filed Feb. 7, 1996 and issued as U.S. Pat. No. 5,907,902.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to the continuous handling of material for processing. More particularly, the present invention relates to a belt feed machine for trimming and forming leads on semiconductor electrical components.
2. Description of the Invention Background
Solid state electrical devices are typically connected to other devices, as well as common substrates, such as printed circuit boards, through the use of electrical connectors, or leads, that are attached to input and output contacts on the device. The quality of the electrical connections between the devices depends upon the proper formation and positioning of the leads and the proper placement of the device.
The individual electrical devices are typically mass produced on common semiconductor substrate, or wafer, which is subsequently cut up to separate the individual dies. Electrical leads are attached to the dies as part of a preformed lead frame in which the leads are flat members extending from a common paddle that is attached to the face of the die. The leads are subsequently trimmed from the lead frame and formed to the desired shave after attachment to the die. Lead frames are often produced as a series of individual frames, each containing electrical leads for attachment to a die. The formation of multiple devices in a single lead frame or strip provides for easier handling of the lead frame during processing. In addition, the lead frames typically contain indexing holes for use in handling and alignment of the lead frame during subsequent processing. After the leads are attached, the devices are typically encapsulated in a molding compound to protect the device from moisture and other deleterious environmental conditions. The lead frames also contain dambars that are attached perpendicularly to the leads to provide structural support to the leads during processing and to prevent molding compound that extrudes from the mold during the encapsulation, known as flashing, and accumulates between the leads from flowing onto the portion of the leads to be attached to another component or onto adjacent devices.
After the plastic encapsulation of the device, the flashing and the dambars must be removed from between the leads. In addition, the electrical leads must be disconnected from the lead frames, trimmed and formed to a desired shape. Finally, the individual devices must be separated from the lead frame to yield the finished product. Each of these processes is generally performed through the use of die and punch tooling.
In the prior art, specially dedicated machines were used to perform each of the die and punch operations. The strips of lead frames would be processed in one machine for a given step and then transported to another machine to further processing. However, the transporting of the strips between machines and the required overhead with loading and feeding strips to the machines greatly increased the processing time and lowered the yield of the devices due to higher incidence of damage. Many of the problems with the use of the individual machines were overcome with development of integrated machines that can be used to perform a series of tooling operations on the framed device in one machine. In those machines, the die and punch tooling operations are linearly arranged in tooling stages and the frames are moved serially through each tooling operation.
The integrated machines use a “walking beam” method to advance the frames through the various stages. In a walking beam method, the lead frame or strip is fed into a track a the inlet of the machine with the lead frame and the faces of the devices in a horizontal orientation. The track supports the edges of the frame while leaving both faces of the device exposed and provides a guide for the strip through the machine as the strip is advanced by fingers extending from the walking beam. When the indexing holes on the lead frame reach the initial position of the first finger of the walking beam, a first set of pins extending from the first finger engage the indexing holes in the lead frame. Actuation of the beam causes the finger to move the lead frame to the first tooling stage. In the tooling stages, the punch tooling is reciprocated to contact and push the lead frame from above so as to disengage the lead frame from the pins on the walking beam finger and to push the lead frame onto the alignment pins attached to the stationary die. Once the lead frame is seated with the alignment pins in the indexing holes, the punch tooling stroke is continued to perform the tooling operation on the device. After the punch tooling disengages the lead frame from the walking beam finger pins, the finger is reciprocated back to its initial position where the pins on the finger engage the next pair of indexing holes in the lead frame, while during the punch operation is occurring. After the punch operation is completed, the punch tooling is reciprocated away from the stationary die and the track and lead frame lift off of the alignment pins on the stationary die. The walking beam finger is then actuated to advance the next frame into the tooling stage, which advances the preceding frame into the next tooling stage. In the final step, the devices are removed, or singulated, from the frames and the frames are discarded. While the use of the walking beam has provided a significant improvement over the prior art, the overall throughput of the machines is limited by the number of times that the strip must be engaged and disengaged by the walking beam pins, which is one of the most time consuming operation during processing. Also, the necessary reciprocal motion of the actuator results in a significant amount of unnecessary machine operations that can affect the long term reliability of the machine. Additionally in the walking beam method, the punch tooling is reciprocated not only to bring the punch into contact with the device, but to align and drive the device into the die tooling. This procedure significantly increases the stroke length of the punch, thereby increasing the possibility of damaging the devices, in addition to potentially causing tooling alignment difficulties due to bending of the frames and/or track.
Some of the problems associated with the unnecessary machine motion and potential overstroke of the punching tooling are resolved with the development of the pinch roller advance machines. The pinch roller machine advances the strip in a vertically oriented position through the use of a series of pinch rollers that contact the edges of the lead frame. The only advancement operation performed by the pinch roller machine operation is the rotation of the pinch rollers to advance the strip, thereby eliminating the unnecessary reciprocal operations associated with the walking beam method. Additionally, the pinch roller machine provides for reciprocal movement of both the punch and die tooling so as to reduce or eliminate many of the problems associated with the movement of only the punch tooling in the walking beam method. However, a limitation the pinch roller method is that the rollers must still be disengaged to some extent in each tooling stage to allow the alignment of the lead frame on the alignment pins of the die tooling prior to performing the tooling operation. Unlike the walking beam method, the disengagement of the strip by the rollers and the alignment of the frame on the die are not inherently interrelated operations, and therefore, must be synchronized to operate correctly, such as through the use of computer controller. The same is true after the completion of the tooling operation and the reengagement of the strip by the pinch rollers. As is the case with the walking beam method, these operations are a critical path operation and tend to limit the throughput of the machines. In addition, the performance of the pinch rollers must be closely monitored to ensure that the rollers do not apply excessive compressive forces on the lead frame during movement of the strip that may tend to damage frame, but that sufficient force is applied to prevent the strip from slipping during rotation of the roller that will cause a misalignment condition.
The present invention is directed to continuous belt feed design which overcomes, among others, the above-discussed problems so as to allow machines that commonly use walking beam transfer arrangements to provide for increased throughput capacities by eliminating the unproductive and time consuming machine operations that are required to reciprocate the walking beam apparatus back into position prior to handling subsequent devices.
SUMMARY OF THE INVENTION
The above objects and others are accomplished by a belt feed apparatus in accordance with the present invention. The apparatus includes at least two rotatable pulleys, an endless belt capable of retaining devices to be processed is disposed around the pulleys such that rotation of the pulleys will cause said belt to travel around said pulleys, and a plurality of paired tooling members, each of said paired tooling members having first and second tooling members disposed on opposing sides of the belt and directly opposing so as to cooperate and perform a tooling operation on the leads when reciprocated toward each other along a common axis. In a preferred embodiment, two horizontally aligned pulleys with vertical axes of rotation are used to rotate the belt in a horizontal plane. The electrical devices are contained in a lead frame which is retained by pins on the belt which pass through indexing holes in the lead frame and the faces of the electrical devices are vertically oriented. The first and second tooling member are horizontally reciprocated by a common cam to perform the tooling operations on the electrical devices and the rotation of the belt is synchronized with the reciprocation of the tooling members. Alternatively, the first and second members can be driven by different cam drives that are synchronized in conjunction with the rotation of the pulleys and the relative orientation of the pulleys, the belt, and the electrical devices can be varied to accommodate specific tooling or spacing requirements.
Accordingly, the present invention provides significant increase in the efficiency of handling devices during sequential operations. These and other details, objects, and advantages of the invention will become apparent as the following detailed description of the present preferred embodiment thereof proceeds.
BRIEF DESCRIPTION OF THE DRAWINGS
Preferred embodiments of the present invention will be described in greater detail with reference to the accompanying drawings, wherein like members bear like reference numerals and wherein:
FIG. 1 is a top view of the apparatus showing three pairs of tooling members;
FIG. 2 is a front view of the apparatus along line 2 — 2 showing three pairs of tooling members;
FIG. 3 is a side view of the apparatus along line 3 — 3 showing a device in position between the tooling members with a top driven pulley and a bottom driven cam;
FIG. 4 is a side view of the apparatus comparable to FIG. 3 showing an alternative cam embodiments without the pulleys and belt; and,
FIG. 5 is a front view showing a 20-lead device in a frame attached to the device side of the belt.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The operation of the apparatus 10 will be described generally with reference to the drawings for the purpose of illustrating present preferred embodiments of the invention only and not for purposes of limiting the same. In accordance with the present invention, an endless belt 30 is disposed around the periphery of at least two horizontally aligned pulleys 20 having vertical axes of rotation. A series of directly opposed first and second tooling members, 40 and 50 , respectively are disposed on opposite sides of the belt 30 . Lead frames 98 containing electrical devices 90 having leads 92 are attached to the endless belt 30 in a vertical orientation and the pulleys 20 are rotated causing the endless belt 30 travel around the pulleys 20 until the lead frames 98 are positioned between the first and second tooling members, 40 and 50 , respectively. The first and second tooling members, 40 and 50 , respectively are then horizontally reciprocated so as to cooperate and perform a tooling operation on the device 90 . The pulleys 20 are then rotated to advance the device 90 to the subsequent pairs of tooling members. After the final share of the device 90 is attained the device 90 is separated from the frame 98 and the frame 98 is discarded.
In a preferred embodiment, two pulleys 20 are mounted on a horizontal bench top 12 with the rotation of the pulleys 20 occurring about the vertical axis 24 , either from below or above as shown in FIGS. 2 and 3, respectively. Two pulleys 20 are preferred to minimize the area occupied by the machine (“the footprint”) and to provide for linear movement of the devices through the tooling equipment. However, any number of pulleys 20 can be used with the present invention to achieve a desired result, for example, different sized and shaped tooling members can be accommodated by adding pulleys to change the shape of the belt. Preferably, the pulleys 20 are constructed from aluminum and the bench top 12 constructed from steel. Other materials of comparable physical characteristics can be used for the pulleys 20 and bench top 12 of the present invention. The actual dimensions and materials of construction can be varied depending upon the size of the devices to be processed.
Preferably, the pulleys 20 are provided with a series of protrusions 22 that are spaced around the perimeters of the pulleys 20 and are capable of engaging holes in the belt 30 and preventing the belt 30 from slipping when the pulleys 20 are rotated. The protrusions 22 are preferably centered and positioned in 45° intervals around the circumference of the pulleys 20 and constructed of a hard tool steel grade to insure accuracy and long life; however, the design, location, and materials of construction of the protrusions can be varied by the skilled practitioner to achieve a desired result.
The endless belt 30 is preferably constructed of stainless steel or other suitable material and has a circumferential length of a size suitable to fit securely around the pulleys 20 . The belt 30 has opposing faces, a pulley face 32 that contacts the periphery of the pulleys 20 and a device face 34 that contacts the devices 90 . The belt has holes 38 through the opposing faces that are preferably centered, sized and spaced to mate with the protrusions 22 on the pulleys 20 as the belt 30 travels around the pulleys. Pins 36 are provided on the device face 34 of the belt to engage the indexing holes 96 and retain the lead frames 98 . Alternatively, the pulleys 20 can be oriented with a horizontal axis of rotation or any angle between the horizontal and the vertical and the belt faces 32 and 34 can be aligned parallel to any given plane depending on the relative elevational alignment of the pulleys. Also, the electrical devices can be oriented at an angle other than vertical to accommodate variations in the tooling layout. Preferably, a track 48 is provided for additional alignment and support for the bottom portion of the frame 98 when the frame 98 is attached to the belt 30 . Preferably, a high torque stepper servomotor is used to rotate the pulleys 20 and to provide precise stop and start control of the belt 30 . A pulley housing 26 can also be incorporated to protect the pulleys 20 and the belt 30 from accidental disruption during operation.
A plurality of paired first and second tooling members, 40 and 50 , respectively, are disposed on opposing sides, 32 and 34 , respectively of the belt 30 . In a preferred embodiment, each pair of tooling members are reciprocally attached to the horizontal bench top 12 in a directly opposed configuration on a monorail barrel roller assembly 58 , which is preferably provided for increased alignment accuracy and loading capability. The first and second tooling members, 40 and 50 , respectively, have opposing tooling faces 42 and 52 , respectively, which are designed to cooperate to perform a desired tooling operation on the devices 90 , when the faces are placed in close proximity by reciprocating the first tooling member 40 and the second tooling member 50 toward one another. In a preferred embodiment, the first tooling members 40 and second tooling members 50 are die and punch tooling, respectively. The actual number of paired tooling members, or stages, and the design of the tooling faces 42 and 52 , respectively, is dependent on the final design of the leads 92 as well as the shape of the leads 92 when fed into the apparatus 10 . FIGS. 1 and 2 show one possible arrangement of three paired tooling members. Additional discussion on the number of stages and the tooling is provided below by way of example.
In a preferred embodiment, each of the paired tooling members 40 and 50 , respectively, are reciprocated in opposite directions along the common rail 58 by a single cam 60 having first and second cam faces, 62 and 64 , respectively. The cams 60 for each tooling stage are driven by a common cam shaft 68 , which provides for synchronization of the devices 90 in each tooling stage. A trough 66 is provided in each of the cam faces, 62 and 64 , respectively, for conversion of the rotational motion of the cam 60 into reciprocal motion of the tooling members, 40 and 50 , respectively. A lever arm 70 connects the cam 60 and the tooling members 40 and 50 , respectively. The lever arm 70 has a cam end 72 that rides in the trough 66 of the cam 60 . The lever arm 70 is mounted on the bench top 12 using a sturdy bearing assembly that creates an axes about which the arm could pivot such that when the cam end 72 moves within the trough 66 the lever arm 70 and the tooling members, 40 and 50 , respectively, reciprocate a fixed distance relative to the amount of the displacement of the cam end 72 . Substantially simultaneous reciprocation of the tooling members 40 and 50 is achieved through the use of complimentary troughs 66 in the first and second cam faces. 62 and 64 . The attachment of a first lever arm 70 between the first cam face 62 and the first tooling member 40 and the attachment of a second lever arm 70 between the second cam face 64 and the second tooling member 50 allow the motion of the tooling members, 40 and 50 , to be commonly controlled. Preferably, the tooling members, 40 and 50 , are spaced equidistant from the location of the devices 90 and the troughs 66 are complimentary so as to provide for minimal translation of the tooling members, 40 and 50 . However, it will be appreciated that the relative translation of each tooling member, 40 and 50 , respectively, and the timing of the movements can be varied by changing the design of the trough 66 in each of the cam faces 62 and 64 , respectively. Also, the cams 60 and the cam shaft 68 are preferably positioned below the horizontal bench top 12 in a cam housing 14 and the lever arms 70 pass through the bench top 12 in order to provide a more compact arrangement of the components. Alternatively, the cams 60 and cam shaft 68 can be mounted on the bench top 12 in a linear arrangement Preferably, a three phase servomotor with a gear reducer and a clutch/brake device is used to provide precise start and stop control over the turning of the cam shaft 68 ; however, other methods of precisely controlling the turning of the cam shaft 68 may be used in the present invention.
In an alternative cam embodiment, as shorn in FIG. 4 the first tooling member 40 and the second tooling member 50 are driven by separate cam shafts, 68 and 69 , respectively. The relative movement of the first and second tooling members, 40 and 50 , respectively, can be synchronized by the use of a common servomotor in conjunction with 90° gears connecting cam shaft 68 with cam shaft 69 or through the use of separate servomotors that are synchronized in some manner such as with a computer.
Also in a preferred embodiment, a computer is used to provide synchronized control over both the pulley servomotor and the cam servomotors. In addition, alignment sensors can be positioned on the respective tooling members, 40 and 50 , to be used in conjunction with the holes 38 in the belt 30 and tied into the computer to ensure the proper alignment of the device 90 in the tooling stage prior to movement of the tooling members, 40 and 50 , respectively. The anticipated speed of processing devices 90 is approximately 3 to 4 strokes/second as compared to a speed of approximately 1 is stroke/second using the prior art methods.
An example of the use of the apparatus of the present invention will be described with respect to the trimming and forming of a 20-lead device as shown in FIG. 5 . In a preferred embodiment for processing the 20-lead device to have J-shaped leads, the pulleys 20 are preferably 5.5 inches in diameter having an axial length of 1.0 inch and constructed from aluminum and spaced apart with approximately 15.0 inches between the axes of rotation. The belt 30 is constructed of ¾ inch wide by 10 mil thick stainless steel. Seven paired tooling members are positioned on opposing sides of the belt 30 and spaced in ¾ inch intervals to perform the tooling operations on the devices. Lead frames 98 containing the devices 90 are feed to the apparatus be conventional methods and are attached to the pins 36 on the belt 30 through the 30 ovular shaped indexing holes 96 in the top portion of the lead frames 98 . The bottom portion of the lead frame 98 is engaged in the track 48 . The pulleys 20 are rotated to cause the belt 30 to travel bringing the lead frame 98 to the first tooling stage in which the die and punch tooling has been designed to remove the flashing from between the leads 92 . The die and punch tooling is reciprocated toward the device and the alignment pins on the die tooling engage the circular indexing holes 95 in the bottom portion of the lead frame 98 . The precise alignment of the lead frame 98 in the die is accommodated without disengaging the lead frame 98 by incremental slide of the ovular shaped indexing holes 96 on the pins 36 . The pulleys 20 are again rotated to move the belt 30 and the lead frame 98 to a second tooling stage where the dambars 97 which are used to provide additional structural support to the lead frame 98 and to prevent the flow of molding compound onto other devices are punched out of the lead frame 98 . The lead frame 98 is when advanced to the next tooling stage where the leads 92 are trimmed to the proper length. The lead frames 98 are then advanced through a series of four forming operations in which the free end of the leads are first bent approximately 90° with respect to the end of the lead attached to the device 90 toward the bottom side of the device 90 . The leads 92 are then bent near the attached end approximately 90° toward the bottom side of the device 90 after which the free end of the leads 92 are again bent so that the free end faces the bottom surface of the device 90 . Finally, the leads 92 is bent toward he bottom surface of the device 90 until the free end of the device 90 is in a close proximate relation with the bottom surface of the device 90 . After this final forming step, the device is singulated from the lead frame 98 by punching the device 90 out of the lead frame 98 . The lead frame 98 can then be discarded.
Those of ordinary skill in the art will appreciate that the present invention provides tremendous advantages over the current state of the art for efficient handling of material through staged processing. In particular, the present invention provides for a continuous feed of lead frames containing electrical devices to a trim and form machine. Also, the present invention allows for short stroke lengths of the punch and die tooling. Thus, the present invention provides a effective method of increasing the capacity of machines used to perform material handling applications. While the subject invention provides these and other advantages over the prior art, it will be understood, however, that various changes in the details, materials and arrangements of parts which have been herein described and illustrated in order to explain the nature of the invention may be made by those skilled in the art within the principle and scope of the invention as expressed in the appended claims.
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A method for moving a workpiece having a first plurality of alignment features and a second plurality of alignment features. The method comprises attaching the workpiece to a workpiece advancer using at least a portion of the first alignment features such that the workpiece can move incrementally relative to the workpiece advancer. The method also includes shifting the workpiece using the workpiece advancer.
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FIELD OF THE INVENTION
The present invention relates to a cemented carbide body, preferably a cylindrical body consisting of at least two grades with individually different compositions, microstructures and properties, especially a body aimed at acting as a blank for a drilling, endmilling or deburring tool.
BACKGROUND
In drilling tools the demands on the periphery and on the center are different with respect to wear resistance and toughness. In drill bits for rock drilling the demands differ between the surface (wear resistance) and the inner part (toughness) as discussed in U.S. Pat. No. 5,541,006, in which is emphasized the use of two grades in a rock drilling bit. The grades are both straight grades with tungsten carbide and Co. Much attention is given to the ability to control the Co migration for which, in this case, an abrupt or discrete change of composition at the interface between the regions is preferred. This problem is also solved by Fischer with the technique known as Dual-Phase or DP-technique, U.S. Pat. No. 4,743,515. Tools as wear parts, rolling rings and slitter/trimming knifes can be manufactured with a method described in U.S. Pat. No. 5,543,235.
These patents, though, deal with combinations of grades containing only WC--Co or WC--Ni. They also refer to applications where just one of the grades is in contact with the work piece material, and the other serves as an `equalizer` or carrier` of pressure or impact.
One patent dealing with cemented carbide drills containing cubic carbides is U.S. Pat. No. 4,971,485, but in that case the WC--Co grade is used in the shaft to avoid damage due to vibrations emanating from the machine.
The present invention relates to a compound cemented carbide body consisting of a core of a tough grade and a surrounding tube of a more wear resistant grade that are both in active contact with the work piece material. The problem when making such a compound body is to avoid the formation of cracks in the outer part or voids and significant porosity at the interface between the two parts due to differences in shrinkage during sintering. In addition, too high stresses in the interface make further manufacturing, e.g., slitting and grinding, impossible. Another problem can be the migration of the binder phase during sintering which results in a leveling of the binder phase content in the two parts. The combination of grades has to fulfil the demands on toughness and wear resistance in the center as well as in the periphery. The grades also have to be compatible with respect to pressing conditions and sintering conditions.
SUMMARY OF THE INVENTION
It is an object of the invention to overcome shortcomings of the prior art.
According to the invention it has been found possible that by a proper choice of composition and microstructure of the two grades the above mentioned problems can be avoided. More particularly, the invention relates to a drill blank with a core of a WC--Co-grade surrounded by a tube of a grade containing also carbides and/or carbonitrides of the elements in group 4-6, preferably Ti, Ta and Nb.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows in 6× magnification a cross section of a drill blank according to the invention wherein A shows the core and B shows the tube; and
FIG. 2 shows in 200× magnification the diffuse interface between the two grades.
DETAILED DESCRIPTION OF THE INVENTION
Drill blanks according to the invention consist of a core and a surrounding tube. The core contains after sintering a Co content of <30, preferably 5-20, most preferably 10-15 wt-% Co, balance WC. In addition to WC, the tube grade has >5 wt-% Co and 5-25, preferably 8-20 wt-%, most preferably 10-15 wt-% of one or more of the carbides and/or carbonitrides of the elements in Groups 4-6 of the Periodic Table, preferably Ti, Ta and Nb. The difference in Co content between core and tube is 1-10 wt-% units, preferably 2-4 wt-% units. There is a 300-500 μm wide transition zone measured as a change in Co-content by microprobe analysis. The core may optionally contain 0.5-2 wt-% cubic carbides.
The grain size of the core grade is <10 μm, preferably 0.5-5 μm, most preferably 0.5-3 μm. The tube grade has a grain size of <10 μm, preferably 0.5-3 μm, most preferably 0.5-1.5 μm.
Blanks according to the invention are made by powder metallurgical methods including compacting in two steps. As an example, a rod with length around 300 mm and diameter 5-15 mm consisting of 10-30 wt-% Co and balance WC with grain size <10 μm is pressed. Preferably, this rod has a grooved form which provides a keying action between it and the surrounding tube. Then a tube of a desired diameter is pressed around the outside of the rod to final green density. The size of the core is preferably 40-60% of the total diameter of the blank. If desired the drill blank can be provided with coolant holes by methods known to those skilled in the art. It has been found that if the difference in Co-content between the tube grade and the core grade is 0-15 wt-% units, preferably 5-10 wt-% units and the tube contains cubic carbides as mentioned above, the blank can be sintered without formation of cracks or voids between the core and the tube.
The pressing and sintering properties of the original grade powders are of utmost importance to get a good result. Pressing conditions are determined by thermal expansion coefficient, shrinkage and required pressing pressure for the grades used. It is within the purview of the skilled artisan to determine these conditions by experiments. Sintering is preferably performed at 1350-1450° C.
After sintering, the rods are usually cut into drill blanks of 50-150 mm, preferably 80-120 mm length. The most useful diameter range is 5-35 mm, preferably 5-20 mm.
The flute is ground with for example a diamond wheel at 18-20 m/sec with a feed of 60-80 mm/min.
In an alternative embodiment, a drill top of length/diameter ratio of 0.5-5.0 is used which is brazed to a shaft.
After finish grinding, drills of the above mentioned kind are suitable for coating by vapor deposition such as PVD with carbide, nitride, carbonitride or oxide or combinations thereof, e.g., TiN, TiAlN, Ti(C,N).
Drills of this invention are particularly useful for machining of stainless steel and normal steel.
EXAMPLE 1
Drills according to the invention were produced by pressing in two stages. First, a cylindrical rod having a length of 300 mm and diameter of 11 mm with a composition of 20 wt-% Co and 80 wt-% WC and grain size 2 μm was pressed. Then, a powder with original composition of 11 wt-% Co, 6.1 wt-% TaC, 1.9 wt-% NbC, 4 wt-% TiC and balance WC and grain size 2.5 μm was pressed around the outside of the rod to final green density. Some of the drills were provided with coolant holes according to a technique well known in the art. After sintering, the Co content of the core grade had decreased from 20 to 14 wt-% and the Co content in the tube grade had increased to 12 wt-%. In addition, significant amounts of the cubic carbides could be detected in the center of the core.
After sintering, the rods were cut into drill blanks of 105 mm length and 14 mm in diameter. The flute and top and bottom of the blanks were ground to final appearance.
EXAMPLE 2
PVD TiN coated drills from Example 1 were tested by drilling in stainless steel AISI 316. Single grade drills of the two original grades used in the drills from Example 1 and one fine grained 1 μm WC-- 10 wt-% Co grade normally used in these cutting conditions were used as references.
The following three test conditions were used with external cooling:
a) v=50 m/min, f=0.14 mm/rev
b) v=82 m/min, f=0.12 mm/rev
c) v=32 m/min, f=0.22 mm/rev
In test a) the drill according to the invention lasted 357 holes, while the single grade drills were worn out after 207 holes (single grade fine grained WC--Co), 149 holes (single grade 11 wt-% Co, 12 wt-% Ta, Nb, Ti carbides, rest WC) and 55 holes (single grade 20 wt-% Co).
At higher speed and lower feed in test b) the drill according to the invention and the fine grained grade made 192 holes while the other single grades made 126 holes (single grade 9 wt-% Co) and 22 holes (single grade 20 wt-% Co).
At lower speed with higher feed in test c) the result was 179 holes for the drill according to the invention while the fine grained grade made 128 holes and the 20 wt-% Co grade made 41 holes before they were stopped because of cracks or wear.
EXAMPLE 3
Drills from Example 1 provided with internal coolant supply holes were tested by drilling in stainless steel. In this test an ordinary P40 drill was used as a reference.
At increased speed (100 m/min, f=0.16 mm/rev) the drill according to the invention drilled 550 holes while the P40 reference drill was totally broken down after only 3 holes.
At normal speed but a higher feed (50 m/min, f=0.25 mm/rev) the P40 drill suffered from chipping after 660 holes and the drill according to the invention was still working after 1100 holes.
At ordinary cutting speed and feed (50 m/min, f=0.16 mm/rev) the two drills were equal in performance and the test was interrupted after 1100 holes.
EXAMPLE 4
Drills from Example 1 provided with internal coolant supply holes were tested on austenitic stainless steel, AISI 304. In this test ordinary P40 and sub-micron K20 drills were used as references.
At normal speed (50 m/min, f=0.16 mm/rev) the drill according to the invention was still working after 2668 holes while the P40 and sub-micron K20 drills were worn out after 2011 and 242 holes, respectively.
At increased feed but normal speed (50 m/min, f=0.30 mm/rev) the drill according to the invention completed 520 holes while the P40 and sub-micron K20 drills completed 110 and 22 holes, respectively.
At increased speed (100 m/min, f=0. 16 mm/rev) the drill according to the invention achieved 198 holes, while the P40 and K20 drills broke down after 1 or 2 holes.
EXAMPLE 5
Drills from Example 1 with internal coolant supply holes, but in 10 mm diameter and coated with Ti(C,N) and TiN were tested by drilling AISI 316 (SS2353), 30 mm through hole drilling. In this test an ordinary fine grained PVD coated drill was used as a reference. Several cutting data combinations were used, and from the results shown below, the drill according to the invention has a much broader working range compared to a conventional drill.
The table below shows the number of holes achieved with the drills used in the test. The test was stopped after 1300 holes even though the drills were not worn out.
______________________________________Cutting Data Speed (m/min) 40 40 40 60 60 60 Feed (mm/rev) 0.13 0.20 0.25 0.13 0.20 0.22______________________________________Ordinary drill 600 100 -- 100 3 -- Drill according to the >1300 400 500 >1300 >1300 500 invention______________________________________
The foregoing has described the principles, preferred embodiments and modes of operation of the present invention. However, the invention should not be construed as being limited to the particular embodiments discussed. Thus, the above-described embodiments should be regarded as illustrative rather than restrictive, and it should be appreciated that variations may be made in those embodiments by workers skilled in the art without departing from the scope of the present invention as defined by the following claims.
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A cemented carbide drill/endmill blank and method of manufacture thereof wherein the drill/endmill includes a core and a surrounding tube with improved technological properties. The difference in Co-content between the core and tube is 1-10 wt-% units and the cubic carbide content is 8-20 wt-% in the tube and 0.5-2 wt-% in the core.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a cover assembly for an electronic device, specifically including a laptop computer, having a base removably mounted in an operative, protective position on the electronic device and movable therewith between open and closed positions. A retaining assembly is disposed at least partially on the interior of the electronic device and is structured to facilitate selective and complete closure thereof. The base is structured to provide access to the connecting ports and other operative components of the electronic device, whether it is in the open or closed positions.
2. Description of the Related Art
Various electronic devices, including laptop or notebook computers are currently being used in commercial, domestic and educational environments. In particular, the younger generation has made ubiquitous use of small, lightweight portable computers in a school or educational environment, wherein such portable computers are carried from class to class. The portability of the laptop computer also lends itself to being carried or utilized during travel on both private and commercial modes of transportation including airlines, automobiles and the like.
Therefore, laptop computers are designed for substantial portability thereby facilitating an individual's access in almost an unlimited number of locations. As such, one problem commonly associated with the transport and use of a portable computer is the requirement for at least some minimal protection against situations where the computer may be dropped or otherwise be subjected to other traumatic forces. In order to overcome such potential problems, there have been developed a variety of different “carrying case” structures. These known structures are similar to luggage type products, inclusive of shoulder straps, handles, etc.
These known carrying cases are available in a wide variety of styles and sizes and are used not only to protect the computer against damage but also to facilitate the transport of the computer in a convenient and comfortable manner. Also, many of the known carrying case devices are structured to protect the portable computer against adverse weather conditions, as well as damage from being dropped, etc. However, many of the known structures of this type are bulky, somewhat heavy and commonly involve relatively complicated enclosure or locking assemblies. As such, known devices of this type mandate that the computer be removed from the interior of the device, placed on an appropriate support structure then disposed in an open orientation for use.
Accordingly, there is a long existing need in the area of cover assemblies for portable computers, which provide protection from both adverse weather conditions as well as traumatic impact. Such a proposed cover assembly should be lightweight, easily mounted in an operative, protective position on the laptop computer in an efficient manner. Further, such a proposed cover assembly should be capable of maintaining the preferred operative position in protective, covering relation to the portable computer or other electronic device during its use, storage or transport. More specifically, the operative position of the proposed cover assembly is maintained when the computer, etc. is in an open position, such as when it is being used, as well as a closed position, such as when the computer is being stored or carried. The ability to maintain the proposed cover assembly in its operative position thereby eliminates the necessity of removing it in order to use the portable computer as is common place with most protective, carrying case type of structures, now available.
Therefore, a proposed cover assembly of the present invention should be formed of a lightweight material having capabilities which facilitate the protection of the computer from adverse weather conditions, as well traumatic force or impact. Moreover, the various structural and operative features of such a proposed cover assembly should enable the portable computer or like device to be used in an intended, conventional manner. Such conventional use would include it being opened and fully closed, while certain retaining structures associated with the proposed cover assembly remain in place. Thereby the proposed cover assembly would be securely but removably disposed in its intended operative position without interfering with the orientation or use of the portable computer or other electronic device.
SUMMARY OF THE INVENTION
The present invention is directed to a cover assembly dimensioned and configured to facilitate its use on an electronic device specifically, but not exclusively, a laptop, notebook or similar type portable computer. Moreover, the cover assembly comprises a base formed from a protective, lightweight, weather resistant, cushioning material such as, but not limited to, Neoprene™. Further, the overall dimension of the cover assembly is such as to overlie, cover and therefore protect at least a majority of the outer surfaces of the top, bottom and rear portions of the portable computer or other electronic device. More specifically, the top, bottom and intermediate segments of the base may move with the top, bottom and rear portions of the electronic device to which they are attached.
In order to securely, but removably maintain the cover assembly in its intended operative position, a retainer assembly is secured thereto. The retainer assembly includes a plurality of retaining elements each fixedly connected to appropriate portions of the cover assembly necessary to maintain it in the aforementioned protective, operative position on the electronic device. Moreover, the disposition, structure and configuration of the plurality of retaining structures are such that they are disposed at least partially on an interior of the electronic device in a manner which facilitates disposition of the electronic device in a completely closed position.
By way of example, as commonly structured and utilized, a conventional laptop computer includes a top portion comprising the display screen of the computer and a bottom portion including operative circuitry and wiring and a keyboard. The top portion is pivotally connected to the bottom portion such that the laptop computer may assume a completely open position for utilization or a completely closed position. In the closed position, the top portion releasably interlocks with the bottom portion. As such, the plurality of retainer assemblies are capable of being removably connected to appropriate and correspondingly disposed parts of the computer or other electronic device such that they are disposed at least partially on the interior of the laptop device when in a closed position. Accordingly, there is a cooperative disposition and structuring of the plurality of retainer structures such that they may be disclosed in substantially overlapping or confronting relation to one another. Alternatively, other embodiments of the cover assembly include an offset but substantially adjacent positioning of the retaining structures relative to one another on the interior of the electronic device or laptop computer when it is in the aforementioned closed position.
Other structural features of the cover assembly of the present invention include an access structure which comprises at least one opening or window formed in the base. In one preferred embodiment the intermediate segment of the base contains the at least one opening or window extending there through. This at least one opening is disposed in aligned relation to connecting ports and other operative components of the electronic device or portable computer so as to facilitate access thereto when it is in either the open or closed position. Similarly, the access structure may additionally include one or more open peripheral sides such as, but not limited to, the opposite peripheral sides of the base as well as the open front side thereof.
By virtue of the dimensions, positions and configurations of the open peripheral sides, access is provided to the connecting ports and/or DVD/ROM, speakers, vent portions, etc. which may typically be disposed about the peripheral sides of the computer or electronic device. The front peripheral side, which is also included in the access structure is sufficiently disposed, configured and dimensioned to provide clear access to the locking/unlocking feature serving to removably interconnect the top portion to the bottom portion of the electronic device, when in a closed position.
Yet additional structural features of the cover assembly of the present invention also include a vent assembly comprising an apertured construction or a plurality of substantially adjacent, spaced apart apertures formed in a preferred location on the base and extending therethrough. This apertured construction would therefore be disposed in overlying or direct fluid communication with the vent facilities, including air intake and/or air passage vents formed on the electronic device or laptop computer to facilitate the cooling thereof during operation. It is noted that the aforementioned vent assembly, including the apertured construction, may be disposed at various locations and/or a plurality of appropriate locations on the base in order to provide fluid communication between one or more vents on the electronic device and the exterior of the cover assembly.
These and other objects, features and advantages of the present invention will become clearer when the drawings as well as the detailed description are taken into consideration.
BRIEF DESCRIPTION OF THE DRAWINGS
For a fuller understanding of the nature of the present invention, reference should be had to the following detailed description taken in connection with the accompanying drawings in which:
FIG. 1 is a front perspective view of one preferred embodiment of the cover assembly of the present invention mounted on an electronic device, such as a portable, laptop computer in an operative position.
FIG. 2 is a perspective side view of the embodiment of FIG. 1 , wherein the electronic device is in a closed position.
FIG. 3 is a rear perspective view of the embodiment of FIGS. 1 and 2 .
FIG. 4 is a perspective front view of the embodiment of FIGS. 1 through 3 .
FIG. 5 is a bottom view representing a vent assembly formed in the cover assembly of the embodiments of FIGS. 1 through 3 such as, but not limited to, being formed in a bottom segment of the cover assembly.
Like reference numerals refer to like parts throughout the several views of the drawings.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
As shown in the accompanying drawings, the present invention is directed to a cover assembly, generally indicated as 10 , structured to cover and protect an electronic device, especially, but not limited to, a portable, laptop or like computer generally indicated as 12 . It is emphasized that while the cover assembly 10 is particularly structured, dimensioned and configured to be utilized with a variety of portable computers, it may also be used with a variety of other electronic devices specifically of the type including a top portion 14 , a bottom portion 15 and a back portion 16 .
As such, the cover assembly 10 comprises a base 11 having a top segment 18 , a bottom segment 19 and an intermediate segment 20 . The intermediate segment 20 may be integrally or otherwise fixedly connected to the other segments 18 and 19 and serves to movably interconnect these top and bottom segments 18 and 19 . Also, the base 11 of the cover assembly 10 , specifically including the top, bottom and intermediate segments 18 through 20 , are respectively dimensioned and configured to overlie a significant or major portion of the outer surface of each of the top, bottom and rear portions 14 through 16 of the portable computer or other electronic device 12 .
As with most conventional portable computers 12 , the top portion and the bottom portions 14 and 15 are pivotally connected to one another and are selectively disposable between an open position as represented in FIG. 1 and a closed position as represented in FIGS. 2 through 4 . The versatility of the cover assembly 10 is such that each of the top, bottom and rear segments 18 through 20 are individually dimensioned and configured to overlie and substantially correspond to the dimension and configuration of the respective portions 14 , 15 and 16 with which they are correspondingly disposed.
Also, the base 11 of the cover assembly 10 , including each of the top, bottom and rear segments 18 through 20 , is formed of a relatively soft, at least partially flexible and resilient, cushioning material such as, but not limited to Neoprene™. Therefore, the cushioning material of which the base 11 is formed provides significant protection of the structure of the portable computer or electronic device 12 , specifically including the outer surface portions thereof, against traumatic forces.
It should be apparent that the specific dimensions and configurations of the base 11 may vary so as to be readily usable on different models, styles or brands of electronic devices or laptop computers 12 . However, the variation in such overall configuration and dimension does not derogatorily affect the uniqueness of the cover assembly 10 but rather adds to its versatility.
As also represented in FIGS. 1 through 4 , the cover assembly 10 comprises a retainer assembly preferably including a plurality of retainer structures 24 , securely but movably connected to the base 11 preferably adjacent to the four corners thereof, as clearly represented in FIG. 1 . Each of the retainer structures 24 have the opposite ends thereof fixedly secured preferably to the inner surfaces of the top and bottom segments 18 and 19 adjacent the outer corners thereof. In addition, each of the retainer structures 24 may at least partially surround the corner portions 14 ′ and 15 ′ of the top and bottom portions 14 and 15 of the electronic device or laptop computer 12 . Therefore, the base 11 is removably but securely disposed in its operative position on the electronic device 12 . Such operative position is further defined by the top, bottom and intermediate segments 18 through 20 disposed in overlying, at least partially covering relation to the corresponding top, bottom and rear portions 14 through 16 , as set forth above, of the electronic device 12 . Further, due to the fact that the base 11 is formed of a flexible material, the various top, bottom and intermediate segments 18 through 20 are movable with the corresponding top, bottom and rear portions 14 through 16 , respectively, of the electronic device 12 , such as when the electronic device is disposed between the open position and the closed position as represented in FIGS. 1 through 4 .
Additional features of the retaining assembly specifically including the preferably four retaining structures 24 , include their disposition and structure facilitating the selective positioning of the top and bottom portions 14 and 15 in a fully closed position as clearly represented in FIGS. 2-4 . As such, the correspondingly disposed retaining structures 24 , when the electronic device 12 is in the closed position, may be disposed in a side by side, offset but substantially adjacent relation to one another when the electronic device or portable computer 12 is in the closed position. However, with reference to FIG. 4 , another embodiment of the retainer assembly, including the preferably four retaining structures 24 , is their disposition in overlapping, substantially confronting relation to one another. In the embodiment of FIG. 4 , the retaining structures 24 are disposed and structured to be at least minimally compressed when in overlapping, confronting relation to one another. This confronting relation to one another further facilitates the complete closure of the top and bottom portions 14 and 15 of the laptop computer or electronic device 12 .
With primary reference to FIGS. 1 and 2 , another feature of the cover assembly 10 of the present invention is the provision of an access structure 30 , at least partially formed in the base 11 . More specifically, the embodiment of FIG. 3 , the access structure 30 comprises at least one opening or window 32 formed in the rear segment 20 of the base 11 and extending therethrough. The one opening 32 is dimensioned and configured to be disposed in substantially aligned relation with connecting ports or other facilities or operative components located in the rear portion 16 of the computer 12 . Such connecting ports and other input facilities and operative features are collectively and generally indicated as 34 and may include one or more USB ports, serial ports, etc. As such, the at least one opening 32 is disposed in aligned relation to the connecting ports, etc. 34 and thereby facilitates clear and easy access thereto through the one opening 32 of the base 11 , when the electronic device or laptop computer 12 is either in the open or closed position. In addition, the access structure 30 may also include one or a plurality of open peripheral sides of the base 11 including opposite lateral peripheral sides 36 and an open front side 38 .
With primary reference to FIG. 4 , the open peripheral sides 36 extend along opposite sides of the base 11 and are more prominent when the base 11 is in its operative position and the laptop computer 12 is in its closed position. As such, the open peripheral sides 36 and/or 38 are disposed so as to provide clear access to the various input facilities, including a DVD/ROM as at 40 and one or more input or output vents as at 42 , as well as a variety of other connecting ports and other operative facilities as is common with portable laptop computers and other electronic devices.
With primary reference to FIG. 5 , an additional preferred embodiment of the present invention also includes a vent assembly generally indicated as 50 . The vent assembly preferably includes a grouping, array or overall apertured construction generally and collectedly indicated as 52 . The plurality of apertures defining the apertured construction 52 may be collectively arranged in a variety of different configurations and may be disposed on and through the top, bottom and/or intermediate segments 18 through 20 of the base 11 . As such, the vent assembly 50 , including the apertured construction 52 is disposed in overlying or fluid communication with one or more vent structures formed in the electronic device or portable computer 12 . Therefore, the vent assembly 50 is not intended to be limited to any one of the plurality of top, bottom and intermediate segments 18 through 20 of the base 11 , but may be positioned at various locations in order to correspond to the disposition of one or more vents of the electronic device or laptop computer 12 .
Yet additional features associated with the cover assembly 10 may also include a display area or display field 56 disposed on or being a part of the exterior surface of one or more segments 18 through 20 of the base 11 . The display field or area 56 is such as to accommodate the disposition of any type of indicia, logo, advertisement, informative data, etc. thereon. Therefore, such indicia, etc. mounted or otherwise disposed on the displayed field or area 56 is readily viewable from an exterior of the base 11 whether it is in its open or closed position in accordance with the position or orientation of the electronic device or laptop computer 12 .
Since many modifications, variations and changes in detail can be made to the described preferred embodiment of the invention, it is intended that all matters in the foregoing description and shown in the accompanying drawings be interpreted as illustrative and not in a limiting sense. Thus, the scope of the invention should be determined by the appended claims and their legal equivalents.
Now that the invention has been described,
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A cover assembly for an electronic device including a laptop or like portable computer, wherein the base is formed of an at least partially protective material and corresponds in dimension and configuration to an outer surface configuration of the electronic device. A retainer assembly comprises a plurality of retaining structures disposed within interior portions of the electronic computer and removably connected thereto so as to maintain the cover assembly in an operative position relative thereto. The retaining structures are disposed and dimensioned to facilitate a complete closure of the electronic device, while remaining at least partially, on the interior of the electronic device. An access structure includes at least one opening formed therein in aligned relation with connecting ports of the electronic device so as to facilitate access to the connecting ports through the at least one opening.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to long life instrumentation magnetic transducers and, more particularly, to a method of manufacturing an instrumentation magnetic transducer so as to substantially extend the operating life thereof.
2. Description of the Prior Art
One of the singular most important parts of a magnetic tape recording and playback system is the transducer which converts electrical signals to magnetic signals and back to electrical signals. While the magnetic transducer was often a highly limiting factor in wideband instrumentation recorder/reproducers, this technology has, throughout the years, improved tremendously. As a consequence, today's high performance magnetic tape recorders can be equipped with transducers that exhibit longer life, higher frequency response, and better signal-to-noise ratios. New modern equipment, combined with years of practical experience, has enabled head manufacturing firms to produce products that are quite superior, both electrically and mechanically, to those available a few short years ago.
For example, about a decade ago, 14 signal tracks was the maximum number allowed for one-inch magnetic tape. As to frequency response, 100 kHz was about the maximum at a tape speed of 60 inches per second (ips). Today, one can obtain 42 signal tracks on one-inch wide tape with a bandwidth of up to 2 MHz at 120 ips. During the 1980's, the recorder/reproducer user will, without a doubt, be offered extended bandwidth capabilities; i.e. three to four Mhz at 120 ips.
There are a number of different types of magnetic transducers that have been developed for wideband magnetic tape recording. One highly desirable type will be referred to herein as the hard-tipped magnetic head and this type of magnetic transducer is described in U.S. Pat. Nos. 3,614,339 and 3,663,765. A hard-tipped magnetic transducer is assembled in two half-bracket pieces which are bolted and/or epoxied together prior to final contouring of the head surface. These half brackets are slotted for receipt of ferrite cores which are wound with the proper number of turns and size of wire. The cores in each half bracket have edge faces which all lie substantially in a common plane which is common with a first surface of each of the brackets. A pair of tip plates are slotted to accomodate shields and grooved in the bottom surfaces thereof for receipt of pole tips made from a very hard, wear resistant material. The tip plates containing the pole tips are then secured to the half brackets having the cores therein, with the bottom surfaces of the tip plates secured to the respective first surfaces of the half brackets. The pole tips engage the edge faces of the cores with a coupling gap between the pole tips so as to define a plurality of signal channels. When viewing the tip plates from the top surfaces thereof after they are attached to the half brackets, the pole tips cannot initially be seen.
Laminated shields are then inserted into the slotted half brackets and the matching half brackets are bonded together. Various epoxies and a minimum of two bolts are used to assure a lasting bond. After the half brackets are attached to form a head stack, contouring and lapping of the top surfaces of the tip plates is performed. This exposes the pole tips and their magnetic circuits to the magnetic tape path.
The surface of the head which is exposed to the magnetic tape includes the pole tips, the laminated shields, and the body of the tip plates between these two elements. Because of the friction generated by the tape moving across this surface, wear to the various elements results. Since the pole tips are made from an extremely hard material, they tend to wear relatively slowly. On the other hand, between the active signal channels of the head, the surfaces of the tip plates provide an area of relatively softer material which typically wears at a faster rate. Since this area wears faster, track edge rounding occurs which ultimately results in head failure due to wear.
Several approaches have been suggested for the solution of this problem. One approach has been the addition of low wear materials to the surface of the heads between the active channels. This has alleviated the problem somewhat, but not in a significant manner. Other solutions include an entirely different head design including ferrite and ceramic materials for the tip plates. These are very expensive solutions and solutions which are often electrically undesirable because of noise problems. In other words, the solutions proposed heretofore have come with their own disadvantages, which have often been equally or more undesirable. If a hard wearing surface could be provided between the active channels without excessive cost and without undesirable electrical characteristics, head life could be extended. However, this has been unachievable heretofore.
SUMMARY OF THE INVENTION
According to the present invention, there is provided a method of manufacturing a magnetic transducer of the above type which indeed provides a hard wearing surface between the active channels. This substantially alleviates the problem of track edge rounding and prevents premature head failure. Furthermore, this is achieved using a metal head without changing the head's electronic characteristics. The result has been an ability to increase the life of a hard-tipped head from approximately 1,000 hours to a time in excess of 3,000 hours.
Briefly, in the manufacture of a composite magnetic transducer of the type including a pair of opposed support brackets having magnetic pole pieces therein, the pole pieces in each bracket having edge faces all lying substantially in a common plane which is common with a first surface of each of the support brackets, and a pair of tip plates, each having grooves in the bottom surface thereof for receipt of pole tips, the bottom surfaces of the tip plates being adapted to be secured to respective first surfaces of the support brackets with the pole tips engaging the edge faces of the pole pieces and with a coupling gap between the pole tips to define active signal channels for cooperation with a magnetic record medium, there is disclosed a method comprising the steps of hard anodizing the bottom surface of the tip plates prior to assembly thereof with the pole tips or the support brackets and subsequently machining the top surfaces of the tip plates to a depth close to the hard anodized areas thereof. The result is that a hard wearing surface is established between the active channels, significantly extending head life.
OBJECTS, FEATURES AND ADVANTAGES
It is therefore an object of the present invention to solve the problem of premature head failure in hard-tipped magnetic transducer heads. It is a feature of the present invention to solve this problem by providing a hard wearing surface between the heads active channels without changing the heads electronic characteristics. An advantage to be derived is that track edge rounding is postponed. A further advantage is that head life is extended. A still further advantage is that metal heads with superb dynamic properties may be used. Another advantage is that the above is achieved at a significant reduction in cost.
Still other objects, features, and attendant advantages of the present invention will become apparent to those skilled in the art from a reading of the following detailed description of the preferred embodiment constructed in accordance therewith, taken in conjunction with the accompanying drawings wherein like numerals designate like parts in the several figures and wherein:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a hard-tipped magnetic transducer;
FIG. 2 is an exploded perspective view of some of the major components of half of the transducer of FIG. 1;
FIG. 3 is an enlarged perspective view of a portion of one of the tip plates of the transducer of FIG. 1;
FIGS. 4-7 are a series of enlarged sectional views of the tip plate of FIG. 3 showing the method of the present invention;
FIG. 8 is an enlarged, partial, transverse sectional view taken along the line 8--8 in FIG. 1;
FIG. 9 is an enlarged sectional view of the signal track area of the transducer of FIG. 1 showing the problem of track edge rounding; and
FIG. 10 is a flow diagram of the principle steps of manufacturing the transducer of FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings and, more particularly, to FIGS. 1 and 2 thereof, there is shown a hard-tipped magnetic transducer (head), generally designated 10, of the type suitable for wideband instrumentation applications. Since the manufacture of magnetic heads is indeed a unique and exacting art, no attempt will be made to discuss all of the sciences involved in the design and manufacture of today's state-of-the-art wideband magnetic heads Only basic concepts and the technology necessary for an understanding of the present invention will be presented. For this purpose, FIGS. 1 and 2 show a seven-track, hard-tipped, wideband magnetic head and the component parts that are used in its construction. It should be generally recognized, however, that the number of channels or tracks may vary in number from one or two for use with tape as narrow as one-eighth inch to one hundred for one-inch wide tape.
Before discussing the method of manufacture of head 10, the major component parts thereof will be described. More specifically, magnetic heads manufactured for instrumentation applications, such as head 10, are assembled in two pieces which are bolted/epoxied together prior to final lapping and contouring of the head surface. Thus, head 10 includes a pair of identical, slotted support brackets 11 which are normally machined from rectangular blocks of brass or aluminum, which materials are typically utilized since their wear characteristics are most similar to the other component parts of the head assembly that interface with the magnetic tape. The material must be non-magnetic to keep the magnetic lines of flux for a given signal track from interfering with adjacent tracks. As a great deal of precision machine work is necessary, the material chosen should be easy to work with. Special aluminum alloys are generally preferred to brass as brass is heavier, harder to work with, and not as temperature stable as aluminum. The material must also be non-corrosive and fungus resistant.
As shown most clearly in FIG. 2, each support bracket 11 has a first series of slots 12 which alternate with a second series of slots 13. Slots 12 receive magnetic pole pieces 14 whereas slots 13 receive shield assemblies 27. These will be described more fully hereinafter.
Magnetic pole pieces, generally designated 14, are loaded into slots 12 in each support bracket 11 so that for each pole piece 14 in each support bracket 11 there is an opposed pole pole piece 14 in the other support bracket 11 (see FIG. 8). Each pole piece 14 includes a ferrite core 15 wound with a number of turns of fine conductive wire 16. In the manufacture of cores 15, a powdered, porous material which is basically iron, magnesium, nickel, and zinc is pressed and fired in a hot oven. The result is a ferrite. The ferrite must have a high permeability or ability to conduct magnetic lines of flux, and a low resistivity Hot-pressed ferrites are made of the same elements as normal ferrites but are pressed during the firing process. They are less porous but of similar magnetic characteristics. Glass bonded hot-pressed ferrites are generally used in video recorder/reproducer magnetic head applications.
Regardless of which process is used, ferrite cores 15 are machined and cut to the proper size and shape for use in pole pieces 14. The individual matching pairs of ferrite cores 15 are wound with the proper number of turns and size of wire 16 and bonded into slots 12 in support brackets 11. Terminal boards or connector plates 41 are inserted in or attached to brackets 11 and the individual wires of windings 16 are connected to terminals 42 by means of a solder process.
It should be noted from an inspection of FIGS. 2 and 8 that each core 15 has an edge face 17. In each half of the assembly, when positioned within slots 12 in brackets 11, the edge faces 17 of all of cores 15 lie substantially in a common plane, which plane is common with the top surface 18 of bracket 11. The reason for this will become more apparent hereinafter.
Transducer 10 includes a pair of tip plates 20, shown clearly in FIGS. 2 and 3, which are slotted, as shown at 21, to accommodate magnetic shields 27, and grooved, at 22, in bottom surface 23 thereof, for receipt of pole tips 25. The number of grooves 22 corresponds to the number of tracks or active channels head 10 is to contain. There is a slot 21 between each groove 22 and on the outside of the first and last grooves 22. Tip plates 20 are typically approximately 0.062 inches thick, slots 21 are typically 0.020 inches wide, and grooves 22 are typically 0.050 inches wide and 0.015 inches deep.
The primary function of tip plates 20 is to hold the pole tips 25 in contact with ferrite cores 15. As was the case with support brackets 11, tip plates 20 must be non-magnetic and have the same properties as brackets 11. Tip plates 20 are preferably made from the same aluminum alloy as brackets 11. It will be seen from an inspection of FIGS. 2 and 8 that the bottom surface 23 of each tip plate 20 is ultimately secured to the top surface 18 of its associated support bracket 11.
A material known as havar, which is much harder than aluminum, may be used for tip plates 20. However, second harmonic distortion problems are associated with the use of havar as it is easily magnetized. Thus, the preferred embodiment does not use havar for tip plates 20.
Inserted into each groove 22 in each tip plate 20 is a pole tip 25 having cross-sectional dimensions which are approximately the same as those of grooves 22. A Japanese-developed alloy called Sendust was originally used for video head designs. The most common American-made hard tip material is known as Alfesil. Alfesil is a combination of aluminum, iron, and silicon. Duroperm is similar to Alfesil in nature and is a trademark of Hamilton Watch Company. Mu-metal, which is 80% nickel and 20% iron, is also a semi-hard material and is used to some degree in head manufacture. While Mu-metal heads are less expensive and easier to manufacture, they have a shorter wear life.
Some magnetic head manufacturers in the United States use laminated pole tips. This procedure is utilized to provide better transfer of the magnetic lines of flux into the ferrite cores 15. Advantages of laminated versus solid designs are greater tip depth (longer wear characteristics) and better signal-to-noise capabilities for a given output response.
As will be explained more fully hereinafter, pole tips 25 are bonded into grooves 22 in each of tip plates 20. Tip plates 20, containing pole tips 25, are then affixed to brackets 11 by bonding surface 23 of the former to surface 18 of the latter. This will bring each of pole tips 25 into contact with the edge face 17 of one of cores 15. It is quite important that each pole tip 25 come into intimate contact with the edge face 17 of its associated core 15. It should also be noted that when viewing tip plates 20 from the top surface 24 thereof, after they have been attached to brackets 11, the pole tips 25 cannot be seen until a subsequent contouring of tip plates 20 is performed.
The final element of transducer 10 is a series of magnetic shields 27 which are spaced equidistantly between each record or reproduce track and at each end of the head stack. Shields 27 extend through the aligned slots 21 in tip plates 20 and slots 13 in support brackets 11. Shields 27 are constructed of thin sheets (laminations) of copper sandwiched between layers of Mu-metal. The particular design of a given head type dictates the number of laminations used. The primary function of shields 27 is to minimize interference between adjacent active channels.
The components of head 10 described above are well-known to those skilled in the art. Furthermore, the process of manufacturing the parts to form a complete transducer is also generally well known. The completed transducer shown in FIG. 1 has the top surfaces 24 of tip plates 20 exposed and machined, as will be described more fully hereinafter, to also expose all of pole tips 25 and all of shields 27. The pole tips 25 are arranged in pairs to define active channels or signal tracks. These tracks are separated by shields 27.
The problem encountered in a conventional head may be seen in FIG. 9. FIG. 9 shows the surface 24 of a conventional head after approximately 1000 hours. It is seen that because the material of tip plates 20 and shields 27 is much softer than the material of pole tips 25, track edge rounding results which ultimately causes head failure. By following the teachings of the present invention, a hard wearing surface is maintained between the active channels, thereby substantially extending head life.
With reference to the drawings and, more particularly, to FIGS. 4-8 and 10 thereof, head 10 is manufactured as follows. Initially, support brackets 11, tip plates 20 and pole tips 25 are carefully machined and pole pieces 14 and shields 27 are assembled. Pole pieces 14 are then loaded into support brackets 11 with edge faces 17 coplanar with each other and with surface 18 of each bracket 11. These steps are generally known in the prior art.
According to the present invention, the manufacturing process next includes an application of a hard sulfuric anodize to the bottom surface 23 of each of tip plates 20. This hard anodizing also covers the inside surfaces of slots 21 and grooves 22. A cross-section of one of tip plates 20 before anodization is shown in FIG. 4. The same cross-section after anodization is shown in FIG. 5. Two areas of anodization 31 and 32 are shown. That is, the process of anodization causes an area 31 of hard surface within the surface which previously existed before the anodization and a second area 32 of hard surface which forms outside of the surface previously in existence. While shown as separate surfaces 31 and 32, the completed result is a single area of hard anodize, hereinafter generally referred to as 33, which has a depth typically of approximately 3 mils.
The anodizing process results in a thick, dense, hard area 33 along surface 23 of tip plates 20. Anodization is applied by an electrolytic oxidation treatment in which the aluminum tip plate 20 is made the anode in a suitable electrolyte. The process controlled by current density. For a thorough discussion of the methods for forming hard anodic coatings on aluminum alloys, reference should be had to military specification No. 8625, revision C, type III, class 1.
After the application of a hard anodize to surface 23 of tip plates 20, which anodizing also covers the inside of shield slots 21 and pole tip grooves 22, the manufacture of transducer 10 proceeds in a generally conventional manner. That is, surfaces 23 of tip plates 20 are lapped and polished to insure flatness. As shown in FIG. 6, pole tips 25 are then cemented in place in grooves 22, preferably using Shell Epon 820/A epoxy.
As will be explained more fully hereinafter, many of the steps of manufacture of transducer 10 require temperature cycling. These cycles vary in time and temperature depending upon the desired function, such as the hardening of epoxies or conditioning of the types of material. These cycles are generally well known to those skilled in the art but will be described briefly. Specifically, at this point, the assembly of tip plates 20 with pole tips 25 cemented therein is cured at 135° C. for approximately six hours.
The next step is to lap surfaces 23 of tip plates 20 to provide uniform flatness across the total bottom surfaces 23 of tip plates 20 and the bottom surfaces of pole tips 25 in the same flat plane. At the completion of this step, tip plates 20 and pole tips 25 have the appearance shown in FIG. 7.
Tip plates 20 are then secured to support brackets 11 by bringing surfaces 23 of the former into contact with surfaces 18 of the latter. Securement is done using a metal-to-metal epoxy, such as Shell Epon 830/A, and suitable pressure hold-down fixtures. The individual support brackets 11 with the tip plates 20 attached thereto are then cured at 121° C. for approximately six hours.
At this point, the two half assemblies are ready to be mated. First, the mating faces of the two assemblies are lapped in the vertical plane to a flatness of five-millionths of an inch across that vertical surface. A gapping material which ultimately forms the recording or reproducing gap 37 is applied, as shown at 34 in FIG. 8, and the two half assemblies are mated, bolted and clamped together. At this time, the individual shields 27 are inserted into the slots 21 in support brackets 11. It should be noted that each shield 27 extends across the entire gap, it not being necessary to provide shields in half pieces as was the case with the remaining components. In any event, after shields 27 are inserted into slots 21, a suitable epoxy material, such as Emerson/Cummings Stycast 2651 mm, is floated inside the spaces between the two half assemblies, such as in the space 35 shown in FIG. 8, which epoxy seals the two half assemblies together. At this point, the entire assembly is again cured at 60° C. for approximately twelve hours.
As shown in phantom in FIG. 8, the completed assembly is such that from the top thereof, the anodized areas 33 in the bottom surfaces of tip plates 20 are not exposed nor are the pole tips 24 in grooves 22. Therefore, the next several operations are designed to contour the top surfaces 24 of tip plates 20 to the final configuration, shown at 36. This is done in several steps. First of all, excess epoxy and excess material are machined off the top surfaces 24 of tip plates 20. This is done by milling whereby a portion of surfaces 24 of tip plates 20 are removed. Next, additional material is removed to expose the material of pole tips 25. Since pole tips 25 typically have a Rockwell hardness of C50, minimum, the process is carefully done by lapping. Head 10 is mounted in a fixture which is placed on a lapping machine.
The greater the depth of tips 25 which remains when transducer 10 is placed into operation, the greater its expected life. In actual present-day manufacture of hard-tipped wideband magnetic heads, this depth can be expected to be as much as three mils. A thicker (deeper) tip would have a longer life, at the expense of a lower output during high frequency operation.
Most importantly, it will be noted that during this contouring step, the top surfaces 24 of tip plates 20 are machined so that the remaining depth of tip plate 20 adjacent the recording gap is just slightly greater than the depth of hard anodized area 33. accordingly, when head 10 is placed into use, and the exposed surfaces of tip plates 20 are exposed to the friction of the magnetic recording material, the resultant wear shortly exposes hard anodized area 33. At this time, the hardness of area 33 is approximately the same as the hardness of pole tips 25, so that wear across gap 37 now proceeds at a substantially uniform rate to significantly slow down the process of track edge rounding. By postponing track edge rounding, head life is substantially extended.
It can therefore be seen that according to the present invention, there is provided a method of manufacturing a magnetic transducer which indeed provides a hard wearing surface between the active channels. This substantially alleviates the problem of track edge rounding and prevents premature head failure. Furthermore, this is achieved using a metal head without changing the heads electronic characteristics. The result has been an ability to increase the life of a hard-tipped head from approximately 1000 hours to a time in excess of 3000 hours.
While the invention has been described with respect to the preferred embodiment constructed in accordance therewith, it will be apparent to those skilled in the art that various modifications and improvements may be made without departing from the scope and spirit of the invention. Accordingly, it is to be understood that the invention is not to be limited by the specific illustrative embodiment, but only by the scope of the appended claims.
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The present disclosure relates to the manufacture of instrumentation magnetic transducers of the type including a pair of opposed support brackets having opposed magnetic pole pieces therein, the pole pieces in each bracket having edge faces all lying substantially in a common plane which is common with a first surface of each of the support brackets, and a pair of tip plates, each having slots in the bottom surfaces of the tip plates being adapted to be secured to respective first surfaces of the support brackets with the pole tips engaging the edge faces of the pole pieces and with a coupling gap between the pole tips to define signal channels for cooperation with a magnetic record medium. According to the present invention, the bottom surfaces of the tip plates are hard anodized prior to assembly thereof with the pole tips or the support brackets and the top surfaces of the tip plates are subsequently machined to a depth to expose the pole tips and to come close to the hard anodized area of the tip plates between the pole tips.
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TECHNICAL FIELD
[0001] This invention relates to a manufacturing method and a structure of conducting lines for a liquid crystal panel, and more particularly to a manufacturing method and a structure of Cu lines formed with Cu tape for a liquid crystal panel.
BACKGROUND
[0002] The amount of transistors in a liquid crystal display (LCD) is approximate over millions. An arrangement of a liquid crystal is controlled through a corresponding transistor and so brightness of each pixel corresponding the transistor is simultaneously determined to display an image. Each transistor connects two conducting lines of a gate line and a data line. The gate line controls a switch of the transistor to make the transistor turn on at a certain time for receiving the image data. At the certain time, the data line delivers data to the transistor. These electrical features of the conducting line and the related line effect a resolution and a response time of the LCD.
[0003] Recently, the developing tendency of the LCD tends to become faster in the response time and larger in the size. In general, a large-size (e.g.: larger than 20 inches for TFT-LCD) LCD employs aluminum (Al) as the base material of the conducting line due to the cost of Al is low and the electrical conductivity of Al is good. Mainly, the conducting line of the LCD is made of a single layer of Al, a double layers of Al and another metal, or Al alloy and another metal.
[0004] The electrical conductivity of the Al conducting line can't break through the bottleneck of the electrical conductivity in those conventional arts regarding the demand for a larger size LCD with higher resolution and faster response time (especially for LCD-TV). It must find new material to satisfy the demand for higher resolution and faster response time.
[0005] Recently, in the semiconductor industry, the Al conducting line is replaced with copper (Cu) having better electrical conductivity for solving the problem of the electrical conductivity. However, no appropriate etching solution for Cu and so to form Cu line is very hard. The damascene process is illustrated as below. First, a hole 20 is formed on a substrate 10 and then a thin and continuous copper seed layer 30 is formed on a surface of the substrate 10 , as shown in FIG. 2A . The copper seed layer 30 can raise an adhesive force between the Cu line and the substrate, and benefit a growth of the Cu line in the successive electroplating process. The copper seed layer 30 must simultaneously cover with a surface of the hole 20 and so the copper seed layer 30 can grow along the surface of the hole 20 during the electroplating process. Furthermore, the copper seed layer 30 must be thin, even, and continuous for avoiding to generate some hollows. However, if there is a doubt about a current leakage resulted from the Cu dispersing to other layers, a barrier layer 40 is added for preventing the Cu from diffusing into other layers, as shown in FIG. 2B . The barrier layer also can avoid the Cu reacting with silicon simultaneously. Hence, the barrier layer 40 is formed before the copper seed layer 30 when there is the aforementioned doubt.
[0006] The electroplating process is then performed to electroplate a Cu electroplating layer 50 on the copper seed layer 30 for making the Cu electroplating layer 50 cover with the copper seed layer 30 continuously, smoothly and fine. The hole 20 will be filled with the Cu electroplating layer 50 and no hollow is produced, as shown in FIG. 3 (the barrier layer not being shown). Finally, a chemical mechanical polishing (CMP) is performed to polish the copper seed layer 30 until the surface of the substrate 10 and only the portion of the copper seed layer 30 inside of the hole 20 is remained, as shown in FIG. 4 . Hence, the forming of the Cu conducting line is finished.
[0007] However, the aforementioned process of the Cu conducting line can not be apply to the TFT-LCD. The main reason is that the area of the liquid crystal panel is quite large compared with the 12 inches wafer in semiconductor industry. Therefore, for the forming of the copper seed layer 30 , the thickness of the copper seed layer 30 is hard to control within a certain range and so some hollows are easily produced therein. Furthermore, the electroplating rate of the Cu electroplating layer must be controlled more accurately for the electroplating rate being almost equal in every position. But, the difficulties of these problems will increase with the size of the LCD. Hence, for a large-size liquid crystal panel, the problems is hard to overcome.
SUMMARY
[0008] In those conventional arts, the process of the Cu conducting line is hard to implement in a large area. One of the objectives of the present invention is to provide a novel process of the Cu conducting line for avoiding forming an uneven Cu seed layer in a large area.
[0009] Another objective of present invention is to employ the manufacturing method of Cu line for forming even Cu lines on a large area.
[0010] Another objective of present invention is to employ a Cu tape to directly stick on a substrate to replace the process of Cu line in the conventional arts for reducing the processes and cost.
[0011] Another objective of present invention is to efficiently avoid forming hollows and defects in Cu lines by employing a Cu tape, and to form even Cu lines.
[0012] Another objective of present invention is to replace Al lines with Cu lines for reducing the RC delay time in the LCD.
[0013] As aforementioned, the present invention provides a structure of Cu line in a liquid crystal panel. The structure has a substrate and a plurality Cu lines, wherein the substrate has a plurality trenches on a surface of the substrate and the plurality Cu lines is formed by sticking a Cu tape on the surface of the substrate and a chemical mechanical polishing is performed to entirely remove a portion of the Cu tape outside of the plurality of trenches.
[0014] Moreover, the present invention provides a manufacturing method of Cu line in a liquid crystal panel. The manufacturing method comprises: forming a plurality trenches on a substrate; sticking a Cu tape on the substrate and the plurality of trenches; and performing a chemical mechanical polishing to remove a portion of the Cu tape outside of the plurality of trenches.
[0015] Due to the difference thickness' of the Cu tape in different parts being slight and hollows and defects in the Cu lines being easily controlled to avoid compared with the conventional arts, the present invention can avoid the problems of unevenness, hollows, etc. Moreover, the steps of process of the present invention is less than of the conventional arts and so both the process time and the cost thereof are reduced efficiently. A different structure or layer also can formed between the substrate and the Cu tape for enhancing a adhesive force of Cu and avoiding a Cu diffusion. Furthermore, to replace Al line with Cu line can reduce the RC delay time in LCD and not limit a resolution and a response time of a large-size LCD resulted from a bottleneck of a electrical conductivity of the Al.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] FIG. 1 is a diagram of forming a hole on a substrate in those conventional arts;
[0017] FIG. 2A is a diagram of forming a copper seed layer on the substrate and the hole in those conventional arts;
[0018] FIG. 2B is a diagram of forming a barrier layer and a copper seed layer on the substrate and the hole in those conventional arts;
[0019] FIG. 3 is a diagram of filling the hole and forming on the surface of the substrate with Cu by electroplating in those conventional arts;
[0020] FIG. 4 is a diagram of performing CMP to remove a portion of Cu tape outside of the hole for forming Cu line in those conventional arts;
[0021] FIG. 5 is a diagram of forming trenches on a substrate in one preferred embodiment of the present invention;
[0022] FIG. 6 is a diagram of sticking a Cu tape on the substrate and the trenches in one preferred embodiment of the present invention;
[0023] FIG. 7 is a diagram of performing CMP to remove a portion of Cu tape outside of the trenches for forming Cu line in one preferred embodiment of the present invention;
[0024] FIG. 8 is a diagram of forming a SiN x layer on the substrate and then forming trenches on the SiN x layer in another preferred embodiment of the present invention;
[0025] FIG. 9 is a diagram of sticking a Cu tape on the substrate and the trenches in another preferred embodiment of the present invention; and
[0026] FIG. 10 is a diagram of performing CMP to remove a portion of Cu tape outside of the trenches for forming Cu lines in another preferred embodiment of the present invention.
DETAILED DESCRIPTION
[0027] Some sample embodiments of the invention will now be described in greater detail. Nevertheless, it should be recognized that present invention can be practiced in a wide range of other embodiments besides those explicitly described, and the scope of the present invention is expressly not limited expect as specified in the accompanying claims.
[0028] Then, the components of the different elements are not shown to scale. Some dimensions of the related components are exaggerated and meaningless portions are not drawn to provide a more clear description and comprehension of the present invention.
[0029] FIG. 5 is a diagram of forming a trench on a substrate in one preferred embodiment of the present invention. First, a plurality of trenches 120 are formed on a substrate 110 . The forming steps of trenches 120 comprise: spin coating a photoresist layer on the substrate 110 ; exposing the photoresist layer with a mask; developing the photoresist layer for removing a portion of the photoresist layer above the areas of trenches 120 ; the substrate 110 is etched with the photoresist layer as a mask for forming the trenches 120 ; and removing the phototresist. In general, the substrate 110 is etched with the wet etching. The solution of etchant is preferably NaOH, HF, or the mixing solution of HF and NH 4 F.
[0030] Referring to FIG. 6 , a Cu tape (or a Cu slice) is struck on the trenches 120 and fill the trenches 120 without hollows and defects. For ensuring that the Cu tape can entirely and easily fill the trench 120 and closely spread on the substrate 110 , the Cu tape 160 is struck with high temperature, high pressure, or high temperature and high pressure to enhance an adhesive force between the Cu tape 160 and the trenches 120 .
[0031] Finally, the Cu tape is polished with chemical mechanical polishing until a surface of the substrate 110 for removing the portion of Cu tape outside of the trenches 120 . As shown in FIG. 7 , the portion of the Cu tape filling with the trenches 120 is the Cu lines.
[0032] A substrate made of any material is suitable for the present invention, especially a large-size LCD. Moreover, the Cu lines also can formed on another structure, not be limited to the glass substrate of the LCD. For example, the Cu line is also formed on a SiN x layer. The SiN x has a feature of lower melting point and so is suitable for the LCD employed glass as a substrate.
[0033] Another embodiment of the present invention is as shown in FIG. 8 . First, a SiN x layer 170 is formed on a substrate 110 and then a plurality of trenches 120 are formed on the SiNx layer 170 . The forming steps of trenches 120 comprise: spin coating a photoresist layer on the substrate 110 ; exposing the photoresist layer with a mask; developing the photoresist layer for removing a portion of the photoresist layer above the area of trenches 120 ; the SiNx layer 170 is etched with the photoresist layer as a mask for forming the trenches 120 ; and removing the photoresist layer. In general, the SiNx layer 170 is etched with wet etching.
[0034] Referring to FIG. 9 , a Cu tape is struck on the trenches 120 and fill the trenches 120 without hollows and defects. For ensuring that the Cu tape can entirely and easily fill the trench 120 and closely spread on the SiN x layer 170 , the Cu tape 160 is struck with high temperature, high pressure, or high temperature and high pressure to enhance an adhesive force between the Cu tape 160 and the trenches 120 .
[0035] Finally, the Cu tape is polished with chemical mechanical polishing until a surface of the SiN x layer 170 for removing the portion of Cu tape outside of the trenches 120 . As shown in FIG. 10 , the portion of the Cu tape filling with the trenches 120 is the Cu lines.
[0036] If an adhesive force between the Cu tape 160 is not good enough or the Cu through diffusive action enters into other structures and results in some problems such as a current leakage, a buffer layer must be formed between the Cu tape 160 and the substrate 110 for enhancing the adhesive force or avoiding the diffusive action of the Cu. The method of adding the buffer layer is: first, forming a buffer layer on the trenches and the substrate, and then sticking the Cu tape on the buffer layer. Therefore, for any embodiments, it can add a buffer layer with the aforementioned method. The demand for a feature of the buffer layer must be that adhesive force between the buffer layer, the substrate 110 , and the Cu tape 160 is good enough. For blocking the diffusive action of the Cu, another feature of the buffer layer must be further request that the capability of blocking Cu is good enough.
[0037] The manufacturing method and the structure of Cu lines for a liquid crystal panel is suitable for the Cu line in a nondisplay region of an edge of the liquid crystal panel in order to avoid shadowing or reflecting a light from a light module of the LCD. The present invention is also suitable for a LCD with chip on glass (COG). The conducting lines of the array in a display region, through an appropriate handling (e.g. a anti-reflective layer is formed on the edge of the conducting lines), also can be formed by employing the present invention.
[0038] In accordance with the present invention, the present invention discloses a manufacturing method and a structure of Cu lines for a liquid crystal panel. The present invention employs a method of sticking Cu tape to replace the method of forming a copper seed layer and electroplating in the conventional arts. Due to the thickness of the Cu tape is very even and the problems of hollows and defects are seldom compared with that in the conventional arts, the problems of unevenness, hollow, etc. can be avoided. Moreover, the forming method of the Cu lines in the present invention can decrease the complexity and the cost. Another structure or layer according to different demand for consideration is also easily formed on (or in) the structure of the present invention. To replace Al lines with Cu lines can reduce the RC delay time of the LCD and not limit the resolution and the response time of a large-size LCD resulted from the bottleneck of the electrical conductivity of the Al.
[0039] Although specific embodiments have been illustrated and described, it will be obvious to those skilled in the art that various modifications may be made without departing from what is intended to be limited solely by the appended claims.
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In those conventional arts, for large-size LCD, the process of copper damascene interconnect has some problems of forming a uneven copper seed layer and forming hollows during electrical plating due to the electrical plating area being too large to electroplate uniformly. In this invention, it employs a Cu tape to directly stick on a substrate to replace forming a copper seed layer and electroplating. Hence, the invention avoids the problem of unevenness and hollows in those conventional arts and so the Cu lines can be applied to the large-size LCD.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention pertains generally to the art of reloading rifle and gun cartridges, and more particular relates to the art of trimming the length of cartridge cases to prepare them for the reloading operation.
2. Description of the Related Art
When a bullet is fired from a cartridge or resized during reloading, the cartridge case expands radially and longitudinally. Thus, during subsequent reloading of a cartridge case it is necessary to resize it so that a bullet may be properly seated and so that the reloaded cartridge will freely and fully enter the chamber of a rifle or gun. Special dies and jigs are used for resizing the radial dimensions of the case. Case trimmers are used to trim cartridge cases to their proper length.
Prior art case trimmers generally provide a collet for grabbing a rim, or head, of the cartridge case. Typically, the collet is tightened onto the case by a threaded hand crank which pulls the collet into a reducing diameter chamber, thus closing the collet onto the case. Prior art case trimmers also have a cutting blade mounted on a shaft that is slidable through a fixed collar. With the case and blade shaft aligned along a longitudinal direction, the blade is set against a mouth of the case and rotated by a hand crank to precisely and evenly trim the case to a predetermined length. An adjustable collar may be used as a jig so that it is only necessary for the operator to turn the blade against the case in a rotating manner until the adjustable collar abuts against a stop thereby preventing further cutting of the blade against the case when the proper length is achieved.
Prior art case trimmers require several turns of the collet adjustment screw to lock a case in position and require many rotations of the blade to properly trim the case to length. Often, bullet reloaders will reload hundreds of cartridges in one session which can make the repetitive task of tightening the collet onto the case and cranking the blade against the mouth of the case very time consuming and tedious. Thus, there is a need in the industry to provide a case trimmer in which the case is easily loaded into the case trimmer and the cutting operation is simplified without loss of precision or adjustability.
SUMMARY OF THE INVENTION
The above-identified problems are solved by the present invention by providing a case trimmer that can receive cases by simply actuating a lever, sliding a case into the holder and then releasing the lever. In addition, the present invention provides for a motorized cutting blade that is directly coupled to a motor that is mounted on a pair of rails for simplified adjustability and quick setup without any loss of precision in the trimming operation.
The present invention replaces the collet used in the prior art with a case holder having a spring-loaded receptacle for receiving the head of a cartridge case. The receptacle is moveable by a lever which moves the receptacle outward away from an abutment so that the head of the case can slide into the receptacle. By releasing the lever, springs urge the receptacle back against the abutment thereby holding the case.
The trimming operation is accomplished by a trimming blade that is rotated by a motor. The motor and blade are slidable along a longitudinal direction so that in one instance the motor and blade are pressing against a mouth of the case for trimming and in another instance the motor and cutting blade are locked in a location away from the case so that cases may be easily removed and inserted into the case holder without interference from the blade.
The motor is preferably mounted on a pair of rails wherein springs urge the motor along the longitudinal direction towards the case holder. An operating handle is used to push the motor against the springs and away from the case holder. The trimming blade and the motor are connected by a rod that passes through a fixed collar which is fixedly mounted to a base thereby supporting the blade for accurate cutting. The rod slides longitudinally and rotates freely in the fixed collar.
The foregoing and additional features and advantages of the present invention will be more readily apparent from the following detailed description, which proceeds with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevational view of a preferred embodiment of a case trimmer of the present invention.
FIG. 2 is a top plan view of the preferred embodiment of the case trimmer shown in FIG. 1.
FIG. 3 is a partial, enlarged cross-sectional view taken along lines 3--3 in FIG. 1 showing a preferred embodiment of a case holder of the present invention wherein a receptacle is arranged to receive a cartridge case.
FIG. 4 is a partial, enlarged cross-sectional view taken along lines 4--4 in FIG. 2 showing a preferred embodiment of a case holder of the present invention wherein a receptacle is arranged to receive a cartridge case.
FIG. 5 is a partial, enlarged cross-sectional view taken along lines 3--3 in FIG. 1 of a preferred embodiment of a case holder of the present invention wherein a cartridge case is held in a receptacle.
FIG. 6 is a partial, enlarged cross-sectional view taken along line 4--4 in FIG. 2 of a preferred embodiment of the case holder of the present invention wherein a cartridge case is held in a receptacle.
FIG. 7 is a partial, enlarged cross-sectional plan view taken along line 7--7 of FIG. 1 showing a preferred embodiment of the present invention.
FIG. 8 is a partial, enlarged cross-sectional view taken along line 8--8 in FIG. 7.
FIG. 9 is a partial, elevational detail view of a preferred embodiment of the present invention as viewed along line 9--9 in FIG. 7.
FIG. 10 is a partial cross-sectional view taken along lines 7--7 in FIG. 1 wherein a motor support is in a retracted and locked position.
FIG. 11 is a partial elevational detail view of the motor support of FIG. 10 as viewed along line 11--11.
FIG. 12 is a front view of a cartridge receptacle taken along the line 12--12 in FIG. 4.
FIG. 13 is partial, enlarged cross-sectional plan view of an alternative embodiment of a case holder of the present invention.
FIG. 14 is partial, enlarged cross-sectional elevation view of the alternative embodiment of FIG. 13.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
In FIGS. 1 and 2 there is shown a preferred embodiment of a case trimmer 10 of the present invention. The case trimmer 10 has a case holder 12, a cutting blade 14 and a motor 16 covered by motor housing 18. The case holder 12 and blade 14 are mounted on a base 20 which in turn is mounted on a platform 22. The motor and housing are attached to depending feet 24 which ride on a pair of parallel rails 26 thus allowing the motor to be moved back and forth along a longitudinal direction 27.
The case holder 12 has a padded lever 28 that is pivotally mounted to a lever support 30 which is bolted to the base 20 by a bolt 32. A lever pin 34 provides the pivotal connection between the lever 28 and the lever support 30.
Various cross-sectional views of the case holder 12 are shown in FIGS. 3-6. In FIGS. 4 and 6 it can be seen that the lever 28 has a beveled surface 36, a portion of which can press against, and move, a compression head 38. A pair of activating rods 40 are fixedly attached to the compression head 38 for movement therewith. In addition, the compression head has a compression shaft 42 that rides within a recess 44 formed in a spring holder block 46. The block 46 is held stationary by bolt 32 which secures it to base 20. A plurality of spring washers 48 are located within the recess 44 which engage the compression shaft 42 thereby urging it and compression head 38 to the left as viewed in FIGS. 3-6.
As mentioned, one set of ends of the actuating rods 40 are attached to the compression head 38. At their distal ends, the actuating rods are provided with heads 50 for attachment to a receptacle 52. Receptacle 52 is provided with a groove 54 for receiving a head 56 of a cartridge case 58. The groove 54 of the shell holder 52 provides a U-shaped opening having its open-end up so that the case 58 can be located at the top of the opening and slid downward to nest within the groove 54 as is diagrammatically illustrated in FIG. 4. The spring holder block 46 is further provided with a tenon 60 which is received in a bore 62 in receptacle 52 and is long enough to partially extend into the area defined by the groove 54.
With respect to FIGS. 3-6 the operation of the case holder 12 will now be explained. Beginning with an empty case holder 12, lever 28 is pressed downward rotating about lever pin 34 so that its beveled edge 36 presses against the compression head 38 thereby moving the compression head against the biasing force of the spring washers 48 and compressing the washers within the recess 44. The movement of the compression head moves the elongate actuating rods 40 in the longitudinal direction 27 thereby moving the receptacle 52 likewise in the longitudinal direction so that the receptacle moves away from the spring holder block 46. In this configuration, shown in FIGS. 3 and 4, the tenon 60 only partially fills the bore 62. The case 58 may now be positioned at the top of the U-shaped opening defined by groove 54 and slid downward into place where it will be aligned with the tenon 60.
After the case 58 has been inserted in the groove 54, the lever 28 can be released so it is no longer pushing against the compression head 38. With the lever pressure relieved, the spring washers 48 urge the compression head 38 to the left as viewed in FIGS. 3-6 which pulls the activating rods 40 through the spring holder block 46 thereby pulling the receptacle 52 towards the spring holder block 46. This movement of the receptacle causes the tenon 60 to fill the bore 62 until it contacts the end of the cartridge head 56. Continued pressure by the spring washers 48 provides a pressure on the tenon 60 against the end of the case 58 thereby holding it firmly in position.
The receptacle 52 may be easily changed to provide a different receptacle 52 having alternatively configured grooves 54 for different configurations of cases 58. As shown in FIG. 12, the receptacle 52 is provided with keyhole openings 64 for receiving the heads 50 of the actuating rods 40. Narrow portions 64a of the openings 64 engage the shaft of the rods 40 thereby holding the receptacle in place.
A preferred embodiment of the case holder 12 is shown in FIGS. 13 and 14 as case holder 12'. In this embodiment, lever 110 is hingedly connected to a housing 112 by lever pin 114. The lever acts upon a compression block 116 having a recess 118 that receives spring washers 120 which are retained in the recess by a spring retention block 122. The block 122 has a raised retainer 124 that is received in the recess 118 so that it rides against the spring washers 120. The block 122 is fixed to the base 20 by a screw 126. Another screw 128 fastens the housing 112 to the block 122.
A pair of actuating rods 130 are threaded into the compression block 116. The rods 130 extend outward from the compression block 116 and pass through the spring retention block 122 and each terminates with a head 132. A receptacle 134 mounts onto the rods 130 and is held in place by the heads 132. Grooves 136 are provided in the receptacle for receiving the head 56 of the cartridge case 58.
The spring washers 120 urge the compression block to the left, as viewed in FIGS. 13 and 14, which likewise urges the rods 130 to the left. Thus, the receptacle 134 is urged against the spring retention block 122. Operationally, this alternative embodiment is functionally equivalent to the embodiment described above.
The mouth 65 of the case 58 (FIG. 10) is trimmed by the blade 14 which is mounted on, and rotates with, a rod 66. The rod 66 slides longitudinally and rotatably within a collar 68 that is fixedly mounted to the base 20. Rod 66 further supports an adjustable collar 70 that is used as a jig to set the depth of cut of the blade 14 into the mouth 65 of the case 58. A trimmer pilot 71 (FIG. 10) is centrally located on the blade 14 and slides into the mouth of the shell 58 during the trimming operation. A different pilot must be used for each different caliber of cartridge case.
The rod 66 is coupled to a drive shaft 72 of the motor 16 by a coupler 74.
As stated, the motor 16 and motor cover 18 are attached to a plurality of feet 24 which ride on a pair of rails 26. Springs 92 are located on the rails and are arranged to urge the motor toward the case holder 12 by pushing against shoulder pins 94. The rails are connected together by a frame 76 that is provided with bolt holes 78, as illustrated in FIG. 8. Locking bolts 80 extend through the bolt holes 78 and have threaded ends 82 that terminate within slots 84 formed in the platform 22. Nuts 86 screw onto the bolts 80 for securing the frame 76 and rails 26 to the platform 22. When the locking bolts 80 are loosened, the rails 26 and frame 76 are free to move longitudinally along the platform within the slots 84 so that the motor and blade may be adjustable longitudinally so that the case trimmer 10 can accept and trim cases 58 of different lengths.
Additionally, the amount of force of the blade 14 against the cartridge case 58 can be adjusted by moving the frame 76, together with the motor 16 and rails 26, along the slots 84. When the frame 76 and rails 26 are located furthest from the case holder 12, then the springs 92 will be nearly extended when the blade 14 engages the cartridge case and the cutting force of the blade on the case will be a minimum. Conversely, when the frame and rails are located closest to the case holder 12 then the springs 92 will be nearly fully compressed when the blade engages the case and therefore the blade will exert a maximum amount of force on the case for maximum cutting per revolution of the blade.
Also located on the frame 76 is a handle 88 that is hingedly connected to the frame 76 by pivot 90. (See FIGS. 7 and 10.) Springs 92 are located on, and circumscribe, rails 26. A shoulder pin 94 is located on each rail 26 for maintaining the location of the springs 92 and for providing a fixed surface for the springs to press upon when they are compressed. The purpose of the springs 92 and motor handle 88 will be described below with respect to the movement of the motor 16 along the rails 26.
To an underside of the motor housing 18, there is secured a depending pin 96 and a handle lock 98 which move with the motor housing 18. A microswitch 99 is also provided and positioned so that when the handle 88 is engaged in the handle lock, the microswitch is depressed.
It is obvious that before a case 58 can be mounted in the case holder 12, the blade 14 must be retracted so that it is out of the way and does not interfere with the case as it is moved into position. This is accomplished by moving the motor 16 and housing 18 along the rails 26 with the handle 88. As can best be seen in FIGS. 1 and 7-11, handle 88 presses against the pin 96 such that when the handle is moved to the right as viewed in FIGS. 1 and 7-11, it pushes against the pin 96 and causes the motor 16 to ride along the rails 26 to the right, away from the case holder 12. Also, as the handle 88 moves to the right, it contacts and rides along a beveled surface 101 of the handle lock 98 until it reaches a distal end 100. Continued movement of handle 88 will cause it to slip past the distal end 100 where the handle 88 can come to rest in a recess 102. In this position, the motor is locked into position at a right-hand end of the rails 26 and the blade 14 is retracted away from the case holder 12 permitting room to load a case 58. Also, when the handle 88 is in the recess 102, it depresses the microswitch 99 opening an electrical circuit between a power source (not shown) and the motor thereby shutting the motor off.
After the case 58 has been inserted in the case holder 12, the handle 88 can be released from the handle lock 98 by moving it slightly to the right and downward so that it clears the distal end 100. When the handle leaves the recess 102 the microswitch 99 closes the motor circuit thereby turning the motor on. The springs 92 then urge the motor 16 to the left by pressing against a pair of the feet 24 as shown in the figures. The springs 92 thus move the motor 16 to the left until the blade 14 comes into contact with the mouth 65 of the case 58. During trimming, the blade 14 and motor 16 continue moving to the left under the urging of the springs 92 until the adjustable collar 70 comes into contact with the fixed collar 68 which prevents further motion to the left of the blade 14 and motor 16, at which time the trimming operation is complete and the motor and blade can be moved to the right by the motor handle 88. The case 58 can be removed from the case holder 12 by operation of lever 28 which again shifts receptacle 52 to the right to relieve the holding force on the case. The case trimmer 10 is then ready to accept another case for trimming.
In view of these and the wide variety of other embodiments to which the principals of the invention can be applied, the illustrated embodiments should be considered exemplary only and not as limiting the scope of the invention.
I claim as the invention all such modifications as may come within the scope and spirit of the following claims and equivalents thereto.
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A motorized case trimmer is disclosed having a lever operated case holder and a motor driven trimming blade. The motor and blade are slidably mounted upon rails for quick and easy movement to provide sufficient clearance for loading a case into the case holder. A motor handle further simplifies the movement of the blade and motor whereby a simple one-step motion of the handle moves the blade and motor and locks them into a retracted position. Releasing the motor handle, permits the motor and blade to slide freely along the rails under urging by a pair of springs. The components of the case trimmer are mounted upon an elongate platform that permits adjustability of the position of the components for accommodating various size cases and for adjusting the cutting force of the blade against the cartridge case.
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FIELD OF THE INVENTION
This invention relates generally to a variable optical attenuator integrated into a small form factor module including a short double clad fiber to suppress cladding modes and reduce polarization dependent loss (PDL) and wavelength dependent loss (WDL).
BACKGROUND OF THE INVENTION
Variable Optical Attenuators (VOAs) are common components used in optical communication networks. One common VOA technology is based on an Electro-Static (ES) Micro-Electro-Mechanical (MEMS) chip. The ES-VOA component has an input optical fiber, a lens, a MEMS tilting minor and an output optical fiber. The lens focuses the input light onto the MEMS tilting mirror, and the reflected light is directed towards the output fiber. A voltage is applied to the MEMS chip, the voltage amplitude controls the mirror tilt angle. By varying the voltage and minor tilt angle, the position of the reflected spot on the output fiber is varied. With the output spot aligned to the center of output fiber core, the attenuation is minimum and limited only by the insertion loss (typically ˜0.5 dB). As the output spot of the beam of reflected light is misaligned relative to the output fiber core, the amount of light launched into the output fiber core is reduced (attenuated), and correspondingly more light is launched into the fiber cladding, and a higher level of attenuation is achieved. The maximum attenuation can be 30 dB and higher, mainly limited by the tilt range of the mirror.
There exist multiple other VOA technologies, each have advantages and disadvantages. Examples include motor-controlled vane attenuator, thermal MEMS-controlled attenuator, Mach-Zehnder attenuators, Electro-Absorption attenuators, liquid-crystal attenuators. The main advantages of the ES-VOA is rapid switching time (<2 ms), compact size (5.56 mm diameter package), low cost, low power dissipation, and high dynamic range (>30 dB). These advantages have made the ES-VOA the most common VOA solution in optical fiber networks applications.
When using VOAs in Dense Wavelength Division Multiplexing (DWDM) optical networks, there are two critical performance parameters that must be minimized: wavelength-dependent loss (WDL) and the polarization-dependent loss (PDL). The WDL refers to the variation in attenuation loss over the specified wavelength range. The PDL refers to the variation in attenuation loss over all states of input polarization. In a VOA, WDL and PDL can vary as a function of the attenuation level. WDL and PDL are undesirable because they contribute to increasing differences in optical power between wavelength channels, which in turn increases the need for channel power equalization and increases the cost and complexity of optical networks. Various design approaches have been proposed to reduce WDL in ES-VOA, see for example U.S. Pat. No. 7,295,748.
In a further development the ES-VOA component is packaged inside a Small Form factor Pluggable (SFP) housing. This product is referred to as SFP VOA. The SFP VOA offers several advantages compared to the stand-alone pigtailed ES-VOA component described above: (1) the SFP VOA is pluggable, the customer can gradually populate SFP VOA slots on the host system board as the system capacity is increased, (2) the SFP VOA pluggability allows for easy replacement, (3) no fiber management is required since the SFP VOA is connectorized, (4) the interface is digital and the attenuation level is set by a firmware instruction from the host board, the customer does not need to design control and drive hardware and does not need to know the specific characteristics of the ES-VOA component.
However, compared to the stand-alone pigtailed ES-VOA, the SFP VOA suffers from higher WDL and higher PDL. The inventors have investigated the possibility that this may be caused by modal interference between the fundamental mode and co-propagating cladding modes launched in the output fiber.
U.S. Pat. No. No. 6,498,888 issued Dec. 24, 2002 to the Institut National D'Optique, discloses a high attenuation fiber with cladding mode suppression. The attenuation mechanism in this disclosure is a cobalt doped core. A double clad fiber absorption attenuator is used to suppress cladding modes. Because the fiber is short, it can support light propagation in high order modes over its short length. When the short fiber attenuator is coupled (spliced) to a fiber, most of the light (e.g. 99%) is launched into the lowest order mode of the short fiber, but because of misalignment some light will be launched in some higher order modes. When the fiber is spliced again through misalignment these high order modes can be coupled back into the core where they would interfere with the lowest order mode. The misalignment in the splice joints is small, and therefore very little light is coupled into a cladding mode. This small amount of cladding modes is suppressed by the double clad fiber.
In a SFP VOA operating at high attenuation, the majority of the light (>99%) will be propagating in the cladding modes, whereas in the application described in U.S. Pat. No. 6,498,888 the majority of the light (>99%) is propagating in the fiber fundamental mode. It is not clear from the teaching of the prior art that a double clad fiber will work to eliminate modal noise where the attenuation is achieved by coupling large amounts of light in the fiber cladding by the ES-VOA. This large amount of light propagating in the cladding mode can couple back into the core of the single mode output fiber and interfere with light that propagated in the fiber lowest order mode resulting in modal noise.
Furthermore, the absorptive attenuation means of the 4,498,888 patent is polarization independent. This offers no teaching for mitigating the PDL degradation experienced by the SFP VOA. There are two factors that contribute to PDL degradation in the SFP VOA. The first factor relates to the variations in polarization states of the cladding modes. As the attenuation is increased, there is increasing optical power in the cladding modes, and since the propagation of cladding modes is not guided, this results in the cladding modes having a variety of polarization states. Accordingly, the amplitude of the modal interference at the core-to-core (between low-order mode in the core and high-order cladding modes) will vary as a function of the cladding modes polarization states, thereby increasing PDL. At high attenuation, given that most of the optical power is in the cladding modes, this effect leads to significant PDL degradation. A second factor is related to the polarization-dependent coupling of the light reflected from the minor coupling into the core. As the attenuation is increased, the beam offset increases, and it would be expected that the coupling of the light into the core would be different depending on whether the input polarization is parallel to the offset plane versus perpendicular to the offset plane. This difference in coupling would also contribute to PDL degradation.
Given the advantages of the SFP-VOA it is highly desirable to mitigate the PDL and WDL in a SFP-VOA device.
SUMMARY OF THE INVENTION
The present invention has found that by suppressing cladding modes using a cladding mode suppressing fiber for the output fiber of a SFP VOA, a negligible degradation in WDL and PDL can be achieved within a short fiber length.
Accordingly, the present invention comprises a variable optical attenuator comprising:
a mirror supported to assume a variable range of positions; a lens; an input optical fiber for transmitting light comprising an optical signal through the lens to the mirror; an output optical fiber for receiving light reflected from the minor and focused through the lens comprising a cladding mode suppressing fiber; an electro-static actuator for controlling a position of the minor such that a selected portion of light from the minor is focused through the lens into a core of the output optical fiber, while a remaining portion of the light reflected from the mirror is coupled into the inner cladding of the output optical fiber, in dependence on the position of the mirror.
The invention is further defined wherein the output optical fiber is less than 100 cm and greater than 15 mm, or wherein the output optical fiber is 15-60 mm.
The invention is further defined wherein the output optical fiber comprises a double clad fiber having a core, an inner cladding and an outer cladding, the core having a higher index of refraction than the inner cladding, and the outer cladding having a higher index of refraction than the inner cladding.
In a further preferred embodiment the invention includes an input optical fiber comprising a cladding mode suppressing fiber.
In a preferred embodiment the invention provides that the variable optical attenuator is housed in a small form factor module.
In a further embodiment of the invention the input optical fiber comprises a double clad fiber having a core, an inner cladding and an outer cladding, the core having a higher index of refraction than the inner cladding, and the outer cladding having a higher index of refraction than the inner cladding.
The invention is further defined wherein the minor comprises a semiconductor micro-electro-mechanical device.
The invention is further defined wherein the variable optical attenuator can provide an attenuation range between 0-30 dB.
BRIEF DESCRIPTION OF THE DRAWINGS
Exemplary embodiments of the invention will now be described in accordance with the drawings, in which:
FIG. 1A is a schematic cross-section of a prior art electrostatic variable optical attenuator;
FIG. 1B is a schematic illustration of an output fiber end with a spot representing the beam of light focused on the fiber core;
FIG. 1C is a schematic illustration of an output fiber end with a spot representing the beam of light focused at an offset position relative to the fiber core to achieve high attenuation;
FIG. 2 is a top view of a prior art small form factor pluggable variable optical attenuator;
FIG. 3 is a schematic cross-section of a fiber to fiber interface at the output port of the SFP VOA of FIG. 2 ;
FIG. 4 is a graph of the wavelength dependent loss due to modal interference effect;
FIG. 5 is a graph of refractive indices for the core, inner cladding and outer cladding of a double clad optical fiber comprising a cladding mode suppressing fiber for use in the present invention;
FIG. 6 is a table showing PDL data measured on SFP VOA prototypes constructed with standard SMF28 fibers; and
FIG. 7 is a table showing PDL data measured on a SFP VOA prototypes constructed with double clad fibers; and
FIG. 8 is a graph of measured PDL as a function of wavelength for one SFP VOA prototype in accordance with the present invention compared to a prior art SFP VOA constructed with SMF28 fiber;
FIG. 9A is a schematic cross-section of an electrostatic variable optical attenuator in accordance with the present invention; and
FIG. 9B is a top view of a small form factor pluggable variable optical attenuator in accordance with the present invention.
DETAILED DESCRIPTION
A prior art VOA technology based on a Electro-Static (ES) Micro-Electro-Mechanical (MEMS) chip, is illustrated in FIG. 1A . The ES-VOA component 10 has an input optical fiber 12 , a lens 14 , a MEMS tilting minor 16 and an output optical fiber 18 . The lens 14 focuses the input light onto the MEMS tilting minor 16 , the reflected light is directed towards the output fiber 18 . Input optical fiber 12 and output optical fiber 18 are supported in ferrule 13 . A voltage is applied to the MEMS chip, and the voltage amplitude controls the mirror tilt angle. By varying the voltage and minor tilt angle, the position of the reflected spot on the output fiber is varied. With the output spot aligned to the center of output fiber core, shown in FIG. 1B , the attenuation is minimum and limited only by the insertion loss (typically ˜0.5 dB). As the output spot 1 , of the beam of reflected light, is misaligned relative to the output fiber core 20 , as seen in FIG. 1C , the amount of light launched into the output fiber core 20 is reduced (attenuated), and correspondingly more light is launched into the fiber cladding 22 , and a higher level of attenuation is achieved. The maximum attenuation can be 30 dB and higher, mainly limited by the tilt range of the mirror 16 .
In a typical application, the ES-VOA 10 will use standard singlemode fiber (e.g. Corning SMF28) for both input and output fibers. The length of the fiber pigtails are typically around 1 meter. Under high attenuation state (>20 dB), most of the light (>99%) will be launched in the fiber cladding where it will propagate in various higher order optical modes referred to as cladding modes. Over the lm length of the fiber pigtail, the cladding modes will diffuse away from the core and cladding light is eventually absorbed by the fiber outer layer. This means that at the fiber splice location at the end of the pigtail, there is negligible cladding mode that can couple back into the fiber core and therefore negligible modal interference effects that would degrade WDL and PDL.
FIG. 2 below illustrates a prior art application where the ES-VOA component 10 is packaged inside a Small Form factor Pluggable (SFP) housing 30 . This product is referred to as SFP VOA. The SFP housing 30 integrates a Printed-Circuit-Board Assembly (PCBA, not shown in FIG. 2 ) with electronic circuits to drive the ES-VOA MEMS chip and includes a microcontroller to store calibration information and allow for a digital communication interface with the host system. The PCBA plugs into an electrical edge connector on the host board. The SFP housing 30 has input 32 and output 34 optical ports, where a LC duplex fiber connector can be inserted into fiber receptacles 32 and 34 to make optical connections with the ES-VOA 10 . The ES-VOA input fiber 12 an output fiber 18 are terminated with a fiber stub inside the fiber receptacles 32 and 34 . As stated above the SFP VOA offers several advantages compared to the stand-alone ES-VOA component.
A typical industry specification for WDL on a stand-alone pigtailed ES-VOA component is 0.2 dB MAX at zero attenuation (insertion loss) and 0.8 dB MAX at 20 dB attenuation. A typical industry specification for PDL on a stand-alone pigtailed ES-VOA component is 0.15 dB MAX over 0˜10 dB attenuation range and 0.30 dB MAX over 20˜30 dB attenuation range. In a SFP VOA application, it is desirable that the WDL and PDL performance of the ES-VOA are similar or not substantially degraded compared to the stand-alone pigtailed ES-VOA component.
Since the fiber length in SFP VOA is approximately 30 mm and not long enough to suppress the cladding modes in a standard singlemode fiber, and the principle of ES VOA attenuation is shifting light to cladding, we considered that it may be the wavelength-dependent and polarization-dependent modal interference effects between cladding mode (coupling back into the fiber core at the fiber-to-fiber interface inside the fiber receptacle) and fundamental mode co-propagating in the fiber core, that is contributing to the PDL and WDL problems.
Given the physical constraints of the SFP housing, and depending on the exact position of the ES-VOA component inside the SFP housing, the length of the input fiber 12 and output fiber 18 is typically in the range of 15˜30 mm which is much shorter than the typical lm long pigtail of a stand-alone ES-VOA component. For the purpose of this description, we assume the fiber length to be ˜20 mm as shown in FIG. 2 .
Due to assembly tolerances, there will be a small core-to-core misalignment (typically <1 um) between the external fiber core 20 ′ and the fiber stub core 20 at the SFP optical port 34 . This misalignment causes a discontinuity along the fiber core waveguide between the output fiber stub core 20 and the external fiber core 20 ′ at the output port 34 of the SFP device, as shown in FIG. 3 . Because of the short fiber length of the output fiber 18 in the SFP VOA configuration, there will remain a significant amount of cladding modes propagating next to the core 20 at the location of the fiber discontinuity, and some of the cladding modes will couple into the output fiber core 20 ′ of the external fiber 34 ′ at output port 34 .
As the light propagates along the output fiber 18 , a phase difference develops due to the differential propagation constants of the fundamental mode propagating in the fiber core 20 and the cladding modes propagating in the cladding region 22 . At the discontinuity location, modal interference is introduced into the core 20 ′ and is transmitted in the output fiber 34 ′. The phase difference will be a function of the wavelength and therefore the modal interference translates into a degradation in Wavelength Dependent Loss (WDL), as seen in FIG. 4 . The amount of modal interference will also depend on the relative polarization state of the interfering modes, therefore this also translates into Polarization Dependent Loss (PDL) degradation. For example, when constructing SFP VOA prototypes using standard SMF28 fibers, we measured PDL levels above 1 dB at 20 dB attenuation. A summary of this data is provided in FIG. 6 . The PDL performance measured on these prototypes are significantly worse than what is typically measured on a stand-alone pigtailed ES-VOA (which would be expected to be 0.3 dB maximum at 20 dB attenuation). Particularly at high attenuation a proportionally larger optical power exists in the cladding modes, which increases modal interference effects and translates into higher levels of PDL.
With reference to FIGS. 9A and 9B , a cladding mode suppressing fiber was used for both the input optical fiber 92 and the output optical fiber 98 of an ES-VOA component 90 in accordance with the present invention, in an effort to suppress the cladding modes in the short output optical fiber 98 and thereby improve the PDL and WDL performance of the ES-VOA component 90 packaged in a SFP housing 30 . For the prototype a double clad fiber was used for both the input optical fiber and the output optical fiber. Though the optical power in the cladding of the input fiber is significantly less than in the output fiber, the input fiber is also a possible contributing source of modal interference. Hence using a cladding mode suppressing fiber for both input and output optical fibers is preferred. An example of the refractive index profile of a double clad fiber is shown in FIG. 5 . In a double clad fiber, there are two cladding regions; the inner cladding 23 with lower refractive index than the fiber core 20 , and the outer cladding 24 with a higher refractive index than the inner cladding 23 . This refractive index profile increases the leakage of cladding modes towards the outer cladding region. This fiber design significantly reduces the modal interference problem described above. The refractive profile shown in FIG. 5 is shown as an example, the present invention is not restricted to a specific double clad fiber design. Double-clad fiber design may vary in terms of their index profile, relative index between regions and physical dimension of the core and inner clad region. The present invention will be effective with any type of fiber design that can sufficiently suppress cladding modes over the fiber length used in the application.
Cladding mode suppression fibers include fibers for which there is suppression of coupling between the fundamental low-order mode propagating in the fiber core region and the higher-order cladding modes propagating in the cladding region. In addition to double clad fiber, or multiple clad fibers, other examples of cladding mode suppression fiber include, but are not limited to: the StockerYale CMS series of low loss cladding suppression fibers; the Nufern CMF cladding mode free and CMS cladding mode suppressed series fibers; hole-assisted fiber designs disclosed in “Cladding mode coupling suppression in hole-assisted fiber BRAGG gratings”, Young-Geun Han, Young Jun Lee, Gil Hwan Kim, Hung Su Cho, Ju Han Lee, Sang Bae Lee, Microwave and Optical Technology Letters, Volume 49, Issue 1, pages 74-76, January 2007; or aircore microstructure fibers such as described in “Suppression of higher-order modes in aircore microstructure fiber designs”, Fini, J. M., Lasers and Electro-Optics, 2006 and 2006 Quantum Electronics and Laser Science Conference. CLEO/QELS 2006, pages 1-2, 21-26 May 2006.
PDL data from two SFP VOA prototypes constructed with a commercially-available double clad fiber HAF-CMS, manufactured by CorActive in accordance with the present invention is shown in FIG. 7 . A significant improvement is demonstrated compared to a configuration using standard SMF28 fibers, verifying the assumption of modal interference as the primary contributor of PDL degradation. Furthermore, FIG. 8 shows PDL data at 20 dB attenuation level as a function of wavelength, showing PDL and WDL in the same plot, and comparing a SFP VOA prototype constructed with standard SMF28 fibers to a prototype constructed with double clad fiber in accordance with this invention. As seen in the plot of graph in FIG. 8 , both PDL and WDL at 20 dB attenuation is reduced from a peak of over 0.7 dB, to a peak of 0.2 dB.
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The invention relates to an electro-static variable optical attenuator suitable for use in a small form factor pluggable module. A short cladding suppressing fiber, such as a double clad optical fiber, dissipates attenuated light coupled to the cladding to reduce modal interference in the output light, while also reducing PDL and WDL introduced by the off set attenuation mechanism.
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The present application relates to U.S. Provisional Patent Application Ser. No. 61/517,613 filed on Apr. 21, 2011 and claims priority therefrom.
The present application was not subject to federal research and/or development funding.
TECHNICAL FIELD
Generally, the invention relates to a method and machine for dewatering paper webs. More specifically, the invention is a process and machine which produces paper having more uniform fiber orientation, sheet structure and improved paper strength characteristics. The improved method and machine includes devices that are arranged in the forming or wet section of a Fourdrinier machine, hereinafter referred to as “Fourdrinier.” The devices are adjusted manually or through a computer and associated drive mechanisms.
An improved method of forming paper using a Fourdrinier is composed of a plurality of foil and vacuum assisted drainage elements that are equipped with on-the-run adjustable angle and/or height dewatering foil blades starting from a paper dryness of 0.1% and extending all the way to 5% dryness within the forming section of a Fourdrinier. The foil blade angle, height, and vacuum level are adjusted as applicable along the entire length of the Fourdrinier dewatering table until a paper dryness of 5% is achieved. These adjustments allow for control of the dewatering rate and turbulence (shear) produced from a paper dryness of 0.1% to 5% on the Fourdrinier dewatering table. Controlling drainage and shear along this entire range of dryness has a direct influence on paper fiber orientation. This has a significant influence on paper strength.
The claimed invention works in unison with the paper machine headbox shear forces to promote maximum fiber orientation in either the cross-machine or machine direction orientation of the paper. The headbox controls fiber orientation through a speed difference between its stock jet speed and the dewatering fabric speed. Once the stock jet lands on the dewatering fabric, it is operated at an overspeed compared to the dewatering fabric “rush” or the same speed “square” or an underspeed “drag” to control the orientation of the fibers during the sheet forming process. Operating the headbox in a rush or drag mode will align fibers in the machine direction which is beneficial for machine direction related strength properties in the finished paper product. Operating in a square mode will produce a maximum cross-machine direction fiber orientation of the fibers in the finished paper product which is beneficial for paper strength properties in the cross-machine direction.
The claimed invention provides control of drainage and turbulence anisoptropic shear after the headbox stock jet lands on the dewatering fabric. After the stock lands, the claimed invention is adjusted to preserve or amplify the fiber orientation characteristics produced by the headbox. In this manner, a higher quality of paper is produced with the instant process and machine. Moreover, existing machines may be retrofitted with various devices and operated in the manner disclosed herein to achieve a superior quality of paper stock.
For example, if machine direction fiber orientation is desired, the headbox jet speed is operated in a rush or drag mode to promote an initial strong machine direction alignment of the paper fibers. From here, the foil blade angles and height, along with the vacuum levels on the vacuum assisted dewatering units are adjusted to produce a high early drainage rate in the initial sheet dewatering zone (0.1% to 2% paper dryness) to immediately freeze the machine direction fiber orientation produced by the headbox. In addition to this, the foil blade angles, heights and vacuum levels are also adjusted to produce a high amount of turbulence in this paper dryness zone (0.1% to 2%). This keeps the fibers mobile and prevents entanglement allowing the headbox shear to become more effective in orientating fibers in the machine direction. After 2% paper dryness, the angle and height and vacuum levels are adjusted to gradually achieve a paper dryness of 5%. However, the foil angle and height are adjusted to achieve only moderate turbulence levels to prevent disruption of the machine direction fiber orientation achieved earlier in the sheet dewatering and forming process.
For cross-machine direction fiber alignment, the process is completely reversed. The headbox stock jet is adjusted to produce a speed difference close to zero (square mode) to promote the highest possible cross-machine direction fiber orientation. However, due to contraction created within the headbox nozzle, a certain unavoidable degree of machine direction fiber alignment is still always present in the fiber slurry when it lands on the dewatering fabric that cannot be reversed through normal Fourdrinier dewatering equipment. To break this natural machine direction fiber orientation up and produce the most random fiber orientation and highest amount of cross-machine direction fiber orientation, the claimed invention is operated as follows. First, the foil blade angles and heights along with the vacuum levels of the vacuum assisted dewatering elements are adjusted to significantly retard drainage in the early sheet forming zone (0.1% to 2% dryness). This is completely opposite of the previously described process for machine direction fiber orientation. In addition to this, the angle and height of the foil blades are adjusted to produce a very high degree of turbulence to prevent fiber entanglement and generate the most random fiber orientation possible for the highest level of cross-machine direction fiber alignment. After a dryness of 2% is achieved, the foil angle and height is adjusted to maintain this high level of turbulence all the way until a paper dryness of 5% is achieved. A very gentle early drainage along with high turbulence all the way until a dryness of 5% will create the most random fiber network resulting in the highest amount of cross-machine direction fiber alignment.
The ability of the claimed process and machine improvement to be adjusted in conjunction with shear significantly increases paper sheet strength properties such as Mullen, Burst, Bending Stiffness, or Concora (machine direction strength properties) and Ring Crush, S.T.F.I, SCT (cross machine direction strength properties) and all other strength properties associated with paper manufacturing.
In addition to this, the claimed invention and sheet forming process also improves other paper properties such as formation, smoothness, uniformity, printability, ply bond strength, and the like.
BACKGROUND OF THE INVENTION
The forming or wet section of a Fourdriner consists mainly of the head box and forming wire. Its main purpose is to generate consistent slurry, or paper pulp, for the forming wire. Several foil, suction boxes, a couch roll, and a breast roll commonly make up the rest of the forming section. The press section and dryer section follow the forming section to further remove water from the stock.
Historically, the main tools used to control paper strength have been fiber species and fiber refining energy along with the orientating shear generated by the speed difference between the headbox jet speed and the dewatering (forming) fabric speed. The first method of continuous sheet forming and dewatering was the Fourdrinier dewatering table which is still the dominant tool used for paper manufacturing today. Since the time of its invention, its impact on sheet strength has been misunderstood or vaguely understood. Also, the ability to directly influence sheet strength through changing the drainage or shear rates produced during the Fourdrinier dewatering and forming process have also been misunderstood. Past technologies such as the VID, Deltaflo or Vibrefoil have been able to adjust drainage and turbulence on the Fourdrinier table. However, these technologies have been used prior to a sheet consistency on the Fourdrinier table of 1.5% or less. The impetus behind their design was simply to generate turbulence in a very short area in an effort to improve paper uniformity (formation) which was claimed to influence sheet strength.
It has been discovered through the use of the claimed improved Fourdrinier papermaking process that controlling drainage and turbulence from a paper dryness of 0.1% to 5% on a dewatering table has a far more significant impact of fiber orientation and paper strength. In addition, the previously described methods of adjusting the headbox shear in conjunction with adjusting drainage and turbulence in this zone to control fiber orientation and paper strength up to this point been has been unknown to anyone other than the inventors of the claimed improved process.
BRIEF SUMMARY OF THE INVENTION
An improved process of Fourdrinier papermaking is used for dewatering and paper quality control and achieved in the forming end of the Fourdrinier. The process uses a plurality of gravity and vacuum assisted drainage elements that are equipped with on-the-run adjustable angle and height dewatering foil blades starting from a paper dryness of 0.1% and extending all the way to 5% dryness. The foil blade angles and heights along with vacuum level are adjusted manually or automatically along the entire length of the Fourdrinier dewatering table until paper dryness of 5% is achieved.
The claimed invention uses a series of gravity assisted drainage elements in the beginning of the Fourdrinier dewatering table. These units are the forming board and hydrofoil section that are equipped with a combination of static and adjustable angle foil blades, as well as foil blades which are height adjustable depending on the paper grade being produced. A low-vacuum section is arranged on the dewatering table after the hydrofoil section. The low-vacuum section includes vacuum assisted drainage elements which are equipped with vacuum control valves, fixed angle and angle adjustable foil blades, as well as foil blades which are height adjustable depending on the paper grade being produced. A high-vacuum section is arranged between the low-vacuum section and a couch roll.
Adjusting the angle and height of the dewatering foil blades along with the vacuum level allows for control of the dewatering rate and turbulence (shear) produced from a paper dryness of 0.1% to 5% on the Fourdrinier dewatering table. Controlling drainage and shear along this entire range of dryness in conjunction with fiber orientation shear produced by the headbox has a direct influence on paper fiber orientation. This has a significant influence on paper strength.
Adjustable dewatering technologies are typically used on the Fourdrinier table in an area directly after the forming board or within a short distance of the forming board and dry the stock to a dryness content of 3.5%. Previously, the design and operation of a Fourdrinier has been focused on fiber orientation control to improve sheet strength.
Other technologies such as the dandy roll or top dewatering machines have been used at a dryness content of 1.5% or greater. However, their purpose has simply been water removal or paper formation improvement, not fiber orientation control liked the claimed invention. Moreover, none of the existing technologies are directed towards precisely controlling fiber orientation as in the disclosed manner.
It is an object of the invention to disclose an improved process for controlling the fiber orientation of paper stock to achieve a better quality paper than is currently produced on a Fourdrinier.
It is a further object of the invention to teach a Fourdrinier having adjustable on-the-run mechanisms for adjusting the height and angle of foils or blades to easily switch over operation of the Fourdrinier to produce paper of higher quality through controlling the orientation of the fibers.
Additional objects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned from practicing the invention. The objects and advantages of the invention will be obtained by means of instrumentalities in combinations particularly pointed out in the appended claims.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
Other objects and purposes of this invention will be apparent to person acquainted with apparatus of this general type upon reading the following specification and inspecting the accompanying drawings, in which:
FIG. 1 illustrates a Fourdrinier papermaking machine incorporating the present invention therein.
FIG. 2 is an enlarged view showing a formline element with stationary and adjustable height foil blades and which forms part of the forming board section of the Fourdrinier.
FIG. 3 shows a Hydroline element with adjustable angle and height foil blades and which forms part of the hydrofoil section of the Fourdrinier.
FIG. 4 shows a Varioline element with stationary and adjustable height foil units and being part of the low-vacuum section.
FIG. 5 shows a Vaculine element with stationary and angle adjustable foil blades and being part of the low-vacuum section.
FIG. 6A shows a detailed view of an adjustable angle foil blade mounted on a C-channel and with the leading edge of the angle adjustable blade raised to +1°. FIG. 6B shows the blade of FIG. 6A having a −3° separation from an underside of the forming fabric. FIG. 6C shows a detailed view of an adjustable height foil blade mounted on a T-bar and with the leading edge of the angle adjustable blade raised to +1°. FIG. 6D shows the blade of FIG. 6C having a −3° separation from an underside of the forming fabric.
FIG. 7A shows a detailed view of an adjustable height activity blade mounted on a C-channel and with the height being at 0 mm where it is in contact with the underside of the forming fabric. FIG. 7B shows the blade of FIG. 7A at a −5 mm height below the forming fabric. FIG. 7C shows a detailed view of an adjustable height blade mounted on a T-bar and with the height being at 0 mm where it is in contact with the underside of the forming fabric. FIG. 7D shows the blade of FIG. 7C at a −5 mm height below the forming fabric.
FIG. 8A shows a control subassembly for an angle adjustable blade taken from an end of the Fourdrinier. FIG. 8B shows a cutaway view of the drive that is actuated to adjust the angle of a respective blade.
FIG. 9A shows a control subassembly for the height adjustable blade taken from an end of the Fourdrinier. FIG. 9B shows a cutaway view of the drive that is actuated to adjust the height of a respective blade.
DETAILED DESCRIPTION OF THE INVENTION
The embodiments of the invention and the various features and advantageous details thereof are more fully explained with reference to the non-limiting embodiments and examples that are described and/or illustrated in the accompanying drawings and set forth in the following description. It should be noted that the features illustrated in the drawings are not necessarily drawn to scale, and the features of one embodiment may be employed with the other embodiments as the skilled artisan recognizes, even if not explicitly stated herein. Descriptions of well-known components and techniques may be omitted to avoid obscuring the invention. The examples used herein are intended merely to facilitate an understanding of ways in which the invention may be practiced and to further enable those skilled in the art to practice the invention. Accordingly, the examples and embodiments set forth herein should not be construed as limiting the scope of the invention, which is defined by the appended claims. Moreover, it is noted that like reference numerals represent similar parts throughout the several views of the drawings.
For illustrative purposes only, the invention will be described in conjunction with a Fourdrinier papermaking machine although the invention and concept could also be applied to hybrid and gap formers. The invention is implemented in the wet section of the Fourdrinier and includes a farming board section 10 , a hydrofoil section 20 , and a low-vacuum section 30 . High-vacuum section 40 does not include automatically adjustable height blades or automatically angle adjustable blades. It should be noted that a headbox is known and is therefore not shown in FIG. 1 . Referring now to FIG. 1 , a Fourdrinier comprises a forming fabric 105 , a breast roll 106 and couch roll 107 . The forming fabric is continuous and travels between the breast and couch rolls 106 , 107 . The stock which comprises pulp fibers is deposited from the headbox to the top surface of the forming fabric 105 at a paper dryness ranging from 0.1% to 1%. Immediately following the headbox, the forming fabric passes over a forming board section 10 which comprises a formline element 11 .
As shown in FIGS. 1 and 2 , the forming board section 10 includes formline element 11 which includes a fixed ceramic lead blade 12 and a plurality of trailing blades 13 , 14 . The blades 13 , 14 are arranged beneath the forming fabric or wire and are fixed atop either stationary or adjustable C-bar or T-bar which extend from one side of the Fourdriner to the other. The support bars preferably comprise fiber reinforced composite. The stationary bars are fixed. In the preferred embodiment, the formline element 11 includes three adjustable trailing blades 13 which may be raised and lowered or the angle adjusted as shown in the respective figures with the use of respective drive 17 A. The drives are arranged at opposite ends of a support bar and fixed. The drives arranged at opposite ends of the support bar operate in concert to lower or raise a respective blade. It should be noted that the air, hydraulic and electrical lines for actuating the drives are not shown for ease in understanding the drawings. It should be understood that it is contemplated that various other drives, pistons or motors including electric and hydraulic ones and their associated supply lines may be employed to practice the invention. The adjustable blades 13 are raised or lowered to cause them to intersect the underside of the forming fabric 105 at a predetermined height to influence the alignment of the fibers within the paper web. Two fixed trailing blades 14 are arranged between the height adjustable blades 13 , as shown. In a preferred embodiment, the height of the adjustable blades may be changed to ensure that the paper fibers are aligned in a desired direction. The forming board lead blade 12 is arranged near the breast roll and is stationary. A plurality of forming board trailing blades is arranged in an alternating sequence of adjustable height blades 13 and stationary blades 14 . The forming board trailing blades preferably comprise ceramic.
During this stage, some water is drained from the stock and a very thin wet sheet is carried over to various other dewatering devices such as foil blades in hydrofoil section 20 , until a sheet paper dryness of around 1% to 1.5% is achieved. Following this, the paper dryness is increased by the foil blades in the Varioline and Vaculine in the low vacuum section 20 to a dryness level of 5%. Next, a paper dryness of 8% to 10% is achieved in the elements of the low-vacuum section 30 and the sheet is transferred to the high-vacuum section 40 to achieve a paper dryness of 18% or greater. Finally, the sheet is transferred over the couch roll where additional dryness level is achieved.
A Fourdrinier composed of the previously described equipment is fitted with a plurality of adjustable angle and height foil blades starting from the forming board section 10 and partially through the low-vacuum section 30 . As the stock travels with the forming fabric 105 , it encounters the adjustable angle and height foil blades at various points along the dewatering table to manipulate the paper web and orient more fibers in a desired direction. On the forming board section 10 and the hydrofoil or gravity section 20 , the adjustable angle foil blades generate a vacuum pulse that dewaters the stock slurry. The amount of drainage produced along each adjustable angle foil blade is determined by the angle setting of the foil blade which can be typically varied between +2 and −4 degrees. A higher angle will produce more drainage.
Also within the forming board section and hydrofoil or gravity section of the papermaking process, the stock encounters adjustable height foil blades. These blades also drain water from the stock slurry. The amount of water drained by the adjustable height foil blades is determined by their height setting in relation to the forming fabric. At a setting of −5 mm, they do not touch the fabric and do not drain any water. At a setting of 0 mm, they are in the same plane as the forming fabric and will drain water. As the adjustable height foil blades are lowered from the fabric, the amount of drainage increases up until a point at which the static and dynamic vacuum forces generated by the adjustable height foil blade are overcome by the tension forces of the forming fabric. When this occurs, the fabric breaks its seal with the adjustable height foil blade and no dewatering occurs. The setting at which this occurs ill vary based on the drainage characteristics of the stock, the stock consistency, and the speed of the forming fabric. As can be understood, changing the height settings will directly influence the fiber orientation.
The wet slurry will leave the hydrofoil section 20 at a consistency of around 1.5% depending on the paper grade and speed. From here, it travels to the initial vacuum assisted foil units in the low-vacuum section 30 which are referred to as the Varioline elements. In addition to natural gravity drainage, these Varioline elements also use a dynamic and an external vacuum source to create a vacuum which is drawn onto the lower side of the forming fabric 105 . This further increases drainage within these units. The Varioline elements are equipped with a plurality of stationary and adjustable height foil blades. Similar to the previous section, as the foil blades are lowered from the forming fabric, the drainage rate increases as discussed above.
Following the Varioline table elements, another set of vacuum assisted units is encountered by the underside of the forming fabric 105 . These table elements are the Vaculine elements which are equipped with adjustable angle foil blades. Again, as the angle of the foil blades is increased, the drainage rate will increase until a consistency of 5% is achieved.
In addition to controlling drainage, the adjustable angle and height foil blades in the previously described drainage units also control turbulence within the wet slurry. This is accomplished through deflection of the forming fabric from its original plane as it travels along the top surface of the adjustable angle foil blades and adjustable height foil blades. This deflection creates a series of accelerations within the stock slurry that results in turbulence and shear within the stock slurry. This turbulence keeps the fibers fluidized and mobile within the wet slurry so that they can be orientated in the cross-machine or machine direction, depending on what the finish paper property strength requirements are.
For example, if machine direction fiber orientation is desired, the headbox jet speed is operated in a rush or drag mode to promote an initial strong machine direction alignment of the paper fibers. From here, the foil blade angles and height, along with the vacuum levels on the vacuum assisted dewatering units are adjusted to produce a high early drainage rate in the initial sheet dewatering zone (0.1% to 2% paper dryness) to immediately freeze the machine direction fiber orientation produced by the headbox.
In addition to this, the foil blade angles, heights and vacuum levels are adjusted to produce a high amount of turbulence in this paper dryness zone (0.1% to 2%). This keeps the fibers from entangling with each other and allows the headbox shear to become more effective in orientating fibers in the machine direction. After 2% paper dryness, the angle and height and vacuum levels are adjusted to gradually achieve a paper dryness of 5%. However, the foil angle and height are adjusted to achieve only moderate turbulence levels to prevent disruption of the machine direction fiber orientation achieved earlier in the sheet dewatering and forming process.
For cross-machine direction fiber alignment, the process is completely reversed. The headbox stock jet is adjusted to produce a speed difference close to zero (square mode) to promote the highest possible cross-machine direction fiber orientation. However, due to friction created within the headbox nozzle, a certain unavoidable degree of machine direction fiber alignment is still always present in the fiber slurry when it lands on the dewatering fabric that cannot be reversed through normal fourdrinier dewatering equipment.
To break this natural machine direction fiber orientation up and produce the most random fiber orientation and highest amount of cross-machine direction fiber orientation, the claimed invention is operated as follows. First, the foil blade angles and heights along with the vacuum levels of the vacuum assisted dewatering elements are adjusted to significantly retard drainage in the early sheet forming zone (0.1% to 2% dryness). This is completely opposite of the previously described process. In addition to this, the angle height of the foil blades are adjusted to produce a very high degree of turbulence to prevent fiber entanglement and generate the most random fiber orientation possible for the highest level of cross-machine direction fiber alignment. After a dryness of 2% is achieved, the foil angle and height is adjusted to maintain this high level of turbulence all the way until a paper dryness of 5% is achieved. A very gentle early drainage along with high turbulence all the way until a dryness of 5% is achieved will create the most random fiber network resulting in the highest amount of cross-machine direction fiber alignment.
After passing through the forming board section, the paper stock is moved along to pass through a hydrofoil or gravity section 20 equipped with Hydroline elements 21 . Each Hydroline element 21 comprises height adjustable blades 13 and angle adjustable blades 22 which are alternately arranged as shown in FIG. 3 . Depending on the paper grade, Hydrolines may also be fixed with all height or angle adjustable blades. The angle adjustable blades are controlled through an angle adjustment mechanism 25 , 27 as shown in FIG. 8A . Height adjustable blades are controlled through a height adjustment mechanism 18 , 21 as shown in FIG. 9B .
FIG. 4 depicts a vacuum assisted unit or Varioline table element 51 with stationary or angle adjustable foil blades and adjustable height blades and being part of the low-vacuum section. The Varioline element 51 comprises a dewatering blade 32 followed by height adjustable blades 13 . A deckle is arranged blades and may comprise a poly material. A drop leg 34 extends down from the Varioline for draining purposes.
FIG. 5 shows a Vaculine element 41 that is part of the low-vacuum section 30 . Vaculine elements 41 are arranged downstream from the last Varioline element 51 . Each Vaculine element includes a fixed blade 14 arranged on stationary T-bar 55 at the front and back ends as shown. Adjustable angle blades 22 are arranged in the Vaculine element. Adjustable deckles are interposed between the fixed blades 14 and the adjustable angle blades 22 as shown. A drop leg 34 extends downward for draining purposes.
FIGS. 6A , 6 B show a detailed view of an adjustable angle blade mounted on a C-channel. Blade 22 comprises a ceramic top 22 A having a yoke 22 B formed of fiberglass reinforced composite and having an offset front side as shown. The yoke 22 B is fitted atop an adjusting mechanism 25 . An underside of the angle adjusting mechanism 25 is secured within C-channel 76 via clamping bar 77 . Protective shield 79 is provided on the blade 22 to prevent items from being caught when the adjustment mechanism 25 is actuated. The C-channel is preferably formed from stainless steel and rests atop the frame of the Fourdrinier.
FIGS. 6C , 6 D show a detailed view of an adjustable angle blade mounted on a T-bar. In this instance, the mounting means is a T-bar 55 instead of the C-channel and clamping bar of FIGS. 6A , 6 B. The adjustment mechanism and remaining parts are the same and operate in similar fashion. The respective angles and their range are also the same.
FIGS. 7A , 7 B show a detailed view of an adjustable height blade mounted on a C-channel. Height adjustable blade 13 includes an upper end having a leading and trailing edge of ceramic 13 A which is fixed in a yoke 13 B preferably formed of fiberglass reinforced composite. A height adjustment mechanism 18 is arranged within the yoke 138 . An underside of the height adjusting mechanism 18 is secured within C-channel 76 via clamping bar 77 . Protective shield 79 is provided on the blade 13 to prevent items from being caught when the height adjustment mechanism 18 is actuated. The C-channel is preferably formed from stainless steel and rests atop the frame of the Fourdrinier. The height adjustment mechanism 18 includes an adjustable T-bar 21 which extends across the Fourdrinier frame and onto which the blade 13 is attached as shown FIG. 9A . In this manner, the drive 17 A raises and lowers the T-bar 21 to adjust the height of the blade 13 in relation to an underside of the forming fabric 105 .
FIGS. 7C , 7 D shows a detailed view of an adjustable height foil blade mounted on a T-bar. In this instance, the mounting means is a T-bar instead of the C-channel and clamping bar of FIGS. 7A , 7 B. The adjustment mechanism is the same and operates in similar fashion. The respective heights and their range are also the same.
FIGS. 8A , 88 shows an angle adjustment mechanism 25 which is a control subassembly for an angle adjustable blade 22 . A rotating T-bar 27 is formed from fiber reinforced composite and is the same length as a substructure upon which it is mounted. The angle adjustment mechanism 25 is secured atop a C-channel. The drive 17 B is indexed to rotate blade 22 over the range of angles shown in FIGS. 6A-D . The blade 22 is attached to the top side of T-bar 27 which is arranged to rotate in a clockwise or counter clockwise direction. In this manner, the angle of the blade 22 relative to the underside of the forming fabric is controlled.
FIGS. 9A , 9 B shows a height adjustment mechanism 78 which is a control subassembly for the height adjustable blade 13 . Blade 13 rests atop a T-bar having a drive 17 A that automatically raises and lowers the blade 13 to a desired height.
Tables 1 and 2 show blade angle and height settings for a paper grade with machine direction fiber alignment and a grade with cross-machine direction fiber alignment. The tables show a variety of angle adjustable and height adjustable blades which may be utilized in the respective regions of the wet end of the Fourdrinier to achieve synergistic results. It should be noted that in this instance seven blades are shown in each section with the abbreviations “H” or “A” indicating that the blade is either height or angle adjustable respectively. Moreover, the gravity units 1-3 correspond to the hydrofoil sections and are three Hydroline elements. Low vacuum units 1-3 correspond to Varioline elements. Low vacuum units 4, 5 correspond to Vaculine elements.
TABLE 1
Machine Direction Fiber Alignment
Low
Vac-
Low
Low
Low
Low
uum
Forming
Gravity
Gravity
Gravity
Vacuum
Vacuum
Vacuum
Vacuum
Unit
Blade
Board
Unit 1
Unit 2
Unit 3
Unit 1
Unit 2
Unit 3
Unit 4
5
1
H
−0.25 mm
A
−1.5°
H
−0.5 mm
A
−1.5°
H
−0.5 mm
H
−0.5 mm
H
−0.5 mm
A
−0.75°
A
−0.0°
2
A
−0.25°
H
−0.5 mm
A
−1.5°
H
−0.5 mm
H
−0.5 mm
H
−0.5 mm
H
−0.5 mm
A
−0.75°
A
−0.0°
3
H
−0.25 mm
A
−1.5°
H
−0.5 mm
A
−1.5°
H
−0.5 mm
H
−0.5 mm
H
−0.5 mm
A
−0.75°
A
−0.0°
4
A
−0.25°
H
−0.5 mm
A
−1.5°
H
−0.5 mm
H
−0.5 mm
H
−0.5 mm
H
−0.5 mm
A
−0.75°
A
−0.0°
5
H
−0.25 mm
A
−1.5°
H
−0.5 mm
A
−1.5°
H
−0.5 mm
H
−0.5 mm
H
−0.5 mm
A
−0.75°
A
−0.0°
6
A
−0.25°
H
−0.5 mm
A
−1.5°
H
−0.5 mm
H
−0.5 mm
H
−0.5 mm
H
−0.5 mm
A
−0.75°
A
−0.0°
7
H
−0.25 mm
A
−1.5°
H
−0.5 mm
A
−1.5°
H
−0.5 mm
H
−0.5 mm
H
−0.5 mm
A
−0.75°
A
−0.0°
TABLE 2
Cross-machine Direction Fiber Alignment
Low
Vac-
Low
Low
Low
Low
uum
Forming
Gravity
Gravity
Gravity
Vacuum
Vacuum
Vacuum
Vacuum
Unit
Blade
Board
Unit 1
Unit 2
Unit 3
Unit 1
Unit 2
Unit 3
Unit 4
5
1
H
−0.0 mm
A
−0.0°
H
−0.0 mm
A
−0.5°
H
−1.0 mm
H
−1.25 mm
H
−1.5 mm
A
−1.5°
A
−2.0°
2
A
−0.0°
H
−0.0 mm
A
−0.25°
H
−0.0 mm
H
−1.0 mm
H
−1.25 mm
H
−1.5 mm
A
−1.5°
A
−2.0°
3
H
−0.0 mm
A
−0.0°
H
−0.0 mm
A
−0.5°
H
−1.0 mm
H
−1.25 mm
H
−1.5 mm
A
−1.5°
A
−2.0°
4
A
−0.0°
H
−0.0 mm
A
−0.25°
H
−0.0 mm
H
−1.0 mm
H
−1.25 mm
H
−1.5 mm
A
−1.5°
A
−2.0°
5
H
−0.0 mm
A
−0.0°
H
−0.0 mm
A
−0.5°
H
−1.0 mm
H
−1.25 mm
H
−1.5 mm
A
−1.5°
A
−2.0°
6
A
−0.0°
H
−0.0 mm
A
−0.25°
H
−0.0 mm
H
−1.0 mm
H
−1.25 mm
H
−1.5 mm
A
−1.5°
A
−2.0°
7
H
−0.0 mm
A
−0.0°
H
−0.0 mm
A
−0.5°
H
−1.0 mm
H
−1.25 mm
H
−1.5 mm
A
−1.5°
A
−2.0°
It is to be understood that the invention is not limited to the exact construction illustrated and described above, but that various changes and modifications may be made without departing from the spirit and the scope of the invention as defined in the following claims. While the invention has been described with respect to preferred embodiments, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in limiting sense. From the above disclosure of the general principles of the present invention and the preceding detailed description, those skilled in the art will readily comprehend the various modifications to which the present invention is susceptible. Therefore, the scope of the invention should be limited only by the following claims and equivalents thereof.
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An improved method for producing paper from pulp includes a plurality of subassemblies arranged in the forming or wet section of a Fourdrinier. The Fourdrinier includes a dewatering table having a plurality of blades that are static and on-the run adjustable in height and/or angle to control orientation of paper fibers in the stack to create a superior quality of paper and improved paper strength characteristics. Gravity and vacuum assisted drainage elements are equipped with on-the-run adjustable angle and height dewatering foil blades starting from a paper dryness of 0.1% and extending all the way to 5% dryness. The result of this process and machine is to improve the paper quality, save fibers and chemicals and fulfill the required paper properties.
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RELATED APPLICATIONS
[0001] This application claims the benefit of priority from U.S. Non-Prov. patent application Ser. No. 14/866,850 filed Sep. 26, 2015 which is entirely incorporated by reference herein.
FIELD
[0002] Related fields include audio speakers, and more particularly miniature audio speakers built into a parent device such as a portable computer, telephone, earpiece, or hearing aid.
BRIEF DESCRIPTION OF DRAWINGS
[0003] FIGS. 1A-1D illustrate a few examples of miniature speakers.
[0004] FIGS. 2A-2E illustrate various speakers with double-walled and single-walled enclosures.
[0005] FIGS. 3A-3E are perspective views of single-walled enclosures incorporating the parent-device wall.
[0006] FIGS. 4A-4B illustrate aspects of sealed signal lines.
[0007] FIG. 5 illustrates an example of retrofitting uncased audio speakers in an existing chassis designed for cased speakers.
[0008] FIGS. 6A-6D illustrate conventional glue-in speakers.
[0009] FIGS. 7A-7H illustrate examples of seals for the fronts of audio speakers that do not necessarily include adhesive.
[0010] FIGS. 8A-8B illustrate a top view and a cross-sectional view of a speaker with an integral, “flangeless” front seal.
[0011] FIGS. 9A-9D illustrate an attachment of a speaker to a speaker-aperture wall with overlapping-tab pairs.
[0012] FIGS. 10A-G illustrate more views and examples of sliding-tab sealing assemblies.
[0013] FIGS. 11A-11D are perspective views of examples of tabbed speaker parts and assemblies.
DETAILED DESCRIPTION
[0014] Dynamic audio speakers may be described as a series of transducers. An electrical input signal is converted by an electromagnet to a varying magnetic field. Variations in the magnetic field cause mechanical motion in a voice coil. The motion of the voice coil vibrates a cone, creating standing waves in a diaphragm stretched across the front of the cone. The vibrating diaphragm interacts with the surrounding medium (usually air) to create an acoustic output.
[0015] The back of the cone experiences mechanical perturbations 180° out of phase with those affecting the front. If the medium surrounding the cone is equally compressible in all directions, the front and back vibrations would tend to cancel each other out. Surrounding the back of the cone with a sealed cabinet, while leaving the air in front of the cone free to move, makes the air less compressible behind the speaker than in front of it. The less-compressible air inside the sealed cabinet (the “back volume”) acts like a restoring spring opposing back vibration.
[0016] Additionally, if the cone were to be placed on a solid surface, the audible rattle or buzz resulting from the cone vibrating against the solid surface might compete with the sound resulting from the electrical input. To prevent this, cones may be mounted to a front wall or baffle to keep the back largely suspended and unable to vibrate against other solid surfaces. Preferably, the baffle is constructed to avoid resonance with the speaker.
[0017] Low frequencies are particularly affected by the out-of-phase vibration of the back of the speaker. These are also the frequencies that may benefit the most from a larger speaker diameter. Design of a dynamic speaker often involves a trade-off between user-perceptible variables such as output frequency range, output level, size and weight, and power handling.
[0018] Compared to sealed speakers where the back volume is ideally airtight, ported or vented speakers have openings, or ports in the back volume, Port parameters are selected to tune the speakers to particular frequencies. The port results in output from the back volume as well as the front. Near the selected frequency, the back output may exceed the front output: Leakage of air from the port weakens the restoring force of the back volume and reduces the diaphragm excursion, preventing the distortion associated with excessive excursion. Ported speakers are sensitive to dimensional errors and their transient responses are inferior to those of sealed speakers. They may be used in conjunction with sealed speakers to boost attenuated bass frequencies, or they may be adjusted to get the highest sound level out of small speaker for limited-frequency applications such as alarms and audible status signals.
[0019] Premium sound quality at venues and in vehicles was historically associated with large, multi-cone speakers built into commensurately large cabinets. The back volume of a sealed or ported speaker functions as an acoustic resonant chamber. Airtight sealing improves the mechanical Q, factor, a dimensionless value associated with underdamping and the suppression of frequency spreading. A definition of mechanical Q based on a single damped mass-spring system is:
[0000]
Q
=
Mk
D
,
[0020] where M is the mass, k is the spring constant, and D is the damping coefficient proportional to the damping force and inversely proportional to the velocity of the oscillating mass.
[0021] FIGS. 1A -ID illustrate a few examples of miniature speakers. In FIG. 1A , an example of a cut-away side view of a speaker omits the basket that may cover the back components, showing permanent magnet 101 , cut ends 102 of the voice coil, diaphragm 103 . 1 , and edge frame 104 . 1 .
[0022] FIG. 1B is a side cut-away view of an example of a cased speaker showing diaphragm 103 . 2 , edge frame 104 . 2 , and vents 106 that connect the air-space 105 just behind diaphragm 103 . 2 to the air-space 115 created by the casing 114 to create a single, unified back volume.
[0023] FIG. 1C is a back perspective view and FIG. 1D is a front perspective view of an example of miniature rectangular speaker. Visible are the frame 104 . 3 , a single front diaphragm 103 . 3 , and dual baskets 107 . 1 and 107 . 2 . Each basket 107 . 1 or 107 . 2 covers a permanent magnet and moving voice coil. Accordingly, FIG. 1C and FIG. 1D illustrate a monolithic speaker with dual voice coils. Some rectangular speakers may alternatively have single voice coils like their circular counterparts.
[0024] FIGS. 2A-2E illustrate various speakers with double-walled and single-walled enclosures.
[0025] In FIG. 2A , a conventional speaker is sealed in a case 201 with signal lines 203 coming out of case 201 to connect to a signal source (not shown). Case 201 may have a placement 204 on or in a parent-device wall 202 . Placement 204 may be a cavity, channel, or niche as illustrated. Alternatively, placement 204 may be a designated area on a planar surface of parent-device wall 202 , optionally with features that locate, orient, or fasten case 201 . Parent-device wall 202 may be structural, such as a chassis, or non-structural, such as a skin or cowling.
[0026] FIG. 2B is an illustration representing a sectional view of the double-walled speaker enclosure through section A-A in FIG. 2A . Dotted outline 224 delineates the boundary of the placement. Speaker 206 has a back volume 205 determined by the interior dimensions of case 201 , which is sealed around speaker 206 and its emerging signal lines 203 . Case 201 may fit within the placement boundary 224 , leaving a surrounding empty space or gap 244 for vibration-damping material, represented in the illustration by springs 209 . For example, vibration damping 209 may include an elastomer sheet or distributed elastomer standoffs, an elastically deformable foam, or an adhesive such as RTV that remains elastically compliant after curing. Without vibration damping, case 201 and parent-device wall 202 might rattle or buzz at resonant frequencies. Holes 207 in parent-device wall 202 form a grill for the speaker.
[0027] In this example, the size of speaker 206 and its back volume 205 is limited by requiring case 201 and vibration damping 209 inside placement boundary 224 . Even if the wall thickness of case 201 and the vibration-damping gap 244 are on the order of a few millimeters or several tenths of a millimeter, these thicknesses may become more and more significant as overall speaker size decreases.
[0028] FIG. 2C is an illustration representing a sectional view, comparable to FIG. 2B , of an uncased audio speaker in a single-walled speaker enclosure. Parent-device wall 202 outside placement boundary 224 forms part of the single enclosure wall which allows the use of an uncased audio speaker 216 having a greater diameter than cased speaker 206 in FIG. 2B . Similarly, the back volume 215 , sealed by speaker cover 211 , includes most of the space inside placement boundary 224 . This volume is significantly larger than back volume 205 in FIG. 2B .
[0029] In some embodiments, speaker 216 is sealed by speaker seal 251 to parent-device wall 202 near integrated grill 207 , and signal-line seal 255 seals around speaker signal lines 213 where they exit back volume 215 . In some embodiments, wall seal 253 may form an airtight seal between speaker cover 211 and parent-device wall 202 . If speaker 216 is to be ported, the port may be placed in one of the seals 251 , 253 , or 255 ; in a part of the parent-device wall; or in speaker cover 211 . In some embodiments, one or more of the seals 251 , 253 , and 255 is elastically resilient to tension, compression, or both. The seal material may be, e.g., an elastomer gasket or O-ring, or a polymer or epoxy applied in liquid form and allowed to cure. Because there is only one wall around the speaker, vibration damping may not be needed.
[0030] FIG. 2D is an example of a digital speaker in the speaker placement of a parent-device wall. Dual-coil rectangular digital speaker 216 . 1 is larger than the largest double-walled speaker, such as 206 in FIG. 2B , that could fit in placement 204 . 1 of parent-device wall 202 . 1 . Digital-signal lines 213 . 1 connect speaker 216 . 1 to a signal source. Existing features such as locating/fastening feature 212 . 1 may be used to locate or attach a speaker cover (not shown in this view).
[0031] FIG. 2E is an example of an analog speaker in the speaker placement of a parent-device wall. Dual-coil rectangular analog speaker 216 . 2 is larger than the largest double-walled speaker, such as 206 in FIG. 2B , that could fit in placement 204 . 2 of parent-device wall 202 . 2 . Analog-signal lines 213 . 2 connect speaker 216 . 2 to an analog signal source. Existing locating/fastening features such as 212 . 2 may be used to locate or attach a speaker cover (not shown in this view).
[0032] FIGS. 3A-3E are perspective views of single-walled enclosures incorporating the parent-device wall.
[0033] In FIG. 3A , speaker placement 304 . 1 in parent-device wall 302 . 1 is simply a grill 307 . 1 with a raised lip 312 . 1 as a locating or fastening feature. For example, raised lip 312 . 1 may include a groove around the outer or inner perimeter for an O-ring, a seat for a gasket, a groove around the top perimeter for adhesive, or a snap-locking latch. Miniature speaker 316 may have a complementary feature on its frame 314 . 1 configured to mate with a feature on raised lip 312 . 1 .
[0034] In FIG. 3B , speaker placement 304 . 2 in parent-device wall 302 . 2 is flat, but recessed. Locating/fastening features 312 . 2 may be for locating pins, fasteners, an injectable adhesive, or the like.
[0035] FIG. 3C is a multi-sided speaker cover for use when the parent-device wall contributes less than 5 sides of the single-walled enclosure. Speaker cover 311 . 1 includes grill 317 . 1 , and in various embodiments, the grill may be part of the speaker cover, part of the parent-device wall, both, or neither. Locating or fastening features 321 . 1 may be complementary to a feature pattern similar to 312 . 2 in FIG. 3B .
[0036] FIG. 3D is another multi-sided speaker cover 311 . 2 including a grill 317 . 2 , structural ribbing 331 , and locating/fastening features 321 . 2 .
[0037] In FIG. 3E , placement 304 . 3 in parent-device wall 302 . 3 contributes three sides to the single-walled enclosure, leaving the other 3 sides to be provided by the speaker cover. In an N-sided single-walled enclosure, the parent-device wall may constitute between 1 and N−1 sides. For example, a 6-sided single-walled enclosure may use 1 to 5 surfaces of the parent-device wall, with the speaker making up the rest. Shared sides, where a side of the single-walled enclosure is partly parent-device wall and partly a section of speaker-cover wall that continues the same plane or contour, are also contemplated.
[0038] For a sealed back volume, or one with precisely controlled porting, the speaker perimeter may not be the only place to use an airtight seal. Signal lines passing from the single-walled enclosure to a signal source outside the enclosure may need to be sealed where they exit the enclosure.
[0039] FIGS. 4A-4B illustrate aspects of sealed signal lines.
[0040] FIG. 4A is a perspective view of an exemplary bracket for sealing signal lines. Bracket 408 includes a notch 418 in one edge.
[0041] FIG. 4B is a perspective view of an exemplary bracket with signal lines sealed in. Signal lines 426 of speaker 416 are held in seal 457 , which is inserted in notch 418 of bracket 408 . Seal 457 may be an elastomer or other elastically compressible material. As illustrated, signal lines 426 terminate outside bracket 408 at signal connector 436 . Sufficient length of signal lines 426 may be reserved inside bracket 408 for frame 414 of speaker 416 to easily reach its placement on the parent-device wall or speaker cover (not shown in this view).
[0042] FIG. 5 illustrates an example of retrofitting uncased audio speakers in an existing chassis designed for cased speakers. Existing chassis 502 has various ribs and placements for various components. Other parent-device walls may include vents, heat-sinks, latches, hinges, and other features. A complex custom parent-device wall may be expensive to retool when an interior component of the parent device is changed. However, speaker placements 504 . 1 and 504 . 2 designed for cased speakers readily accommodate uncased speakers 516 . 1 and 516 . 2 without needing modification.
[0043] Speaker covers and seals to provide the remaining sides of a single-walled enclosure would be significantly smaller and simpler to have made than a customized chassis. On the other hand, a future version of chassis 502 could be designed with smaller placements 514 . 1 and 514 . 2 and accordingly sized speaker covers (not shown in this view) specifically tailored for uncased speakers, potentially simplifying the speaker placement and speaker cover (rectangular rather than L-shaped) and freeing up space for other interior components.
[0044] FIGS. 6A-6D illustrate conventional glue-in speakers.
[0045] FIG. 6A is a top view of wall 602 near the speaker aperture. Adhesive 603 is applied around the perimeter of the speaker aperture in wall 602 . Adhesive 603 may be applied as a liquid or as a double-sided adhesive strip.
[0046] FIG. 6B is a view of the front face of speaker 606 that will be sealed to the speaker aperture. Adhesive 603 is applied around the perimeter of the front of speaker 606 . This is an alternative to the adhesive placement of FIG. 6A that might be used, for example, if the speaker aperture were difficult to reach or close to other components that might be harmed by stray drops of adhesive.
[0047] FIG. 6C is a top view of a speaker 606 pushed against aperture wall 602 through adhesive 603 . Speaker 606 is placed face-down over the aperture in wall 602 with the adhesive 603 dispersed between them. Apparent coverage gap 605 . 1 might be filled in under speaker 606 so that it does not actually affect the seal. On the other hand, the air gap may persist all the way through the line of adhesive 603 , in which case the speaker sound will be degraded. A visual inspection from this angle is inconclusive. There is both a risk of wasting more effort on a faulty speaker assembly and a risk of rejecting a speaker that would have been satisfactory.
[0048] FIG. 6D is a side view of the assembly from FIG. 6C . Looking at the seal from the side, gap 605 . 2 is evident. This gap will probably leak air from the back volume out into the surrounding environment, reducing the mechanical Q of the speaker assembly and negatively affecting its sound. Depending on the design of the part that includes wall 602 , a side view like this may be challenging to obtain.
[0049] Besides consistency and repeatability challenges, the use of adhesives may increase inventory overhead because of the need to use it before it expires. Some adhesives give off toxic fumes and vapors as they cure, requiring safety precautions. Finally, adhesive application and curing is often done as a batch process; this may slow down manufacturing if the rest of the processes are continuous processes.
[0050] FIGS. 7A-7H illustrate examples of seals for the fronts of audio speakers that do not necessarily include adhesive.
[0051] FIG. 7A represents a gasket 751 . 1 and FIG. 7B represents an O-ring 751 . 2 . When made of material that is mechanically resilient to compression, and compressed by surrounding structures, gasket 751 . 1 and O-ring 751 . 2 may serve as resilient layers providing the desired air-tight seal.
[0052] FIGS. 7C-7E represent examples of different configurations of O-rings or other resilient layers for use in speaker assemblies.
[0053] In FIG. 7C , resilient layer 751 seals the front rim of the frame of speaker 716 . 1 . Speaker aperture 762 , the parent device's output for speaker sound 730 , is surrounded by a shoulder 722 wide enough for resilient layer 751 to contact the frame edge without interfering with the diaphragm motion of speaker 716 . 1 .
[0054] In FIG. 7D , resilient layer 751 seals the side of the frame of speaker 716 . 2 to the inside wall of a counterbore in wall 712 . 2 surrounding speaker aperture 762 , the parent device's output for audio signals 730 . Optionally, the speaker frame rim, the counterbore, or both may have features, such as grooves, to hold resilient layer 751 in position.
[0055] In FIG. 7E , resilient layer 751 seals a flange 726 extending out around the front rim of the frame of speaker 716 . 3 to a raised ridge in wall 712 . 3 surrounding speaker aperture 762 , the parent device's output 1 for audio signals 730 .
[0056] FIGS. 7F-7H represent examples of different configurations of gaskets or other resilient layers in speaker assemblies.
[0057] Resilient layer 751 . 1 or 751 . 2 in wall 712 may have an aperture 762 approximately matching the speaker aperture to expose the diaphragm or other front speaker surface, as in FIGS. 7F and 7G . Resilient layer 751 . 1 in FIG. 7F may cover the entire shoulder around speaker aperture 762 . By contrast, resilient layer 751 . 2 in FIG. 7G may cover only part of the shoulder around speaker aperture 762 . Alternatively, as illustrated in FIG. 7H , resilient layer 751 . 3 may cover the aperture 762 , with the center region forming a grill, e.g., by perforations 751 . 3 .
[0058] FIGS. 8A-8B illustrate a top view and a cross-sectional view of a speaker with an integral, “flangeless” front seal. The front of the speaker includes an integrated resilient section on the front of the speaker near the rim of the frame, alleviating the need for a gasket, O-ring, or other extra part to make the front seal. When the speaker is assembled into an enclosure, part of the enclosure is intended to compress the integral seal, and the integral seal is intended to provide a restoring force that maintains a substantially air-tight seal and, optionally, may also cushion the speaker from external shock or vibration.
[0059] FIG. 8A is a top view of a speaker with an integral seal. Although the example relates to a round speaker, any other suitable shape may be substituted (e.g., rectangular). Frame 804 around the perimeter, integral seal 809 , and the outer lobe of diaphragm 803 are referenced.
[0060] FIG. 8B is a cross-section through A-A of FIG. 8A . Frame 804 has a bead 814 around the rim 804 that may optionally be used as part of a snap-lock. Integral seal 809 extends beyond the level where rim 804 and a mating part in the speaker enclosure (not shown in this view) meet or overlap. Integral seal 809 , like the O-rings and gaskets it replaces, may be compressible and may exert a restoring force against the compression.
[0061] As illustrated, integral seal 809 is an annular bump with a rounded cross-section, but any suitable shape may be used. Space 819 inside or under integral seal 809 may be hollow, filled with the same material as integral seal 809 , filled with the same material as diaphragm 803 (if diaphragm 803 is made of a different material than integral seal 809 ), or filled with any other suitable material to produce the desired gasket-like properties. Similarly, integral seal 809 may be made of the same material as frame 804 , or the same material as diaphragm 803 (if diaphragm 803 is made of a different material than frame 804 ), or any other suitable material to produce the desired gasket-like properties. Optionally, frame 804 , integral seal 809 , and diaphragm 803 may be fabricated as a single piece.
[0062] FIGS. 9A-9D illustrate an attachment of a speaker to a speaker-aperture wall with overlapping-tab pairs. The speaker has a first set of tabs, the speaker-aperture vicinity of the wall has a second set of tabs, and the attachment is based on sliding one set over or under the other until they at least partially overlap. Snap-fit, stiction, or any other suitable method may be used to keep the tabs in place, thus keeping the parts joined. A material that is elastically resilient to compression (e.g., certain elastomers) forms a seal between the parts and prevents rattling. For a sealed speaker, the resilient material may preferably be nonporous. For a ported speaker, the resilient material may be porous enough to pass the amount of air prescribed for the port.
[0063] FIG. 9A is an exploded cross-sectional view of wall 912 near, but not intersecting, the speaker aperture (see section A-A in FIG. 10A ) showing a wall tab 922 raised above the top of wall 912 by wall tab standoff 932 ; speaker 916 (face-down in this view) and speaker tab 926 ; and resilient layer 951 between the two. In some embodiments, resilient layer 951 may be built onto the perimeter or front of speaker 916 at the time of speaker manufacture.
[0064] FIG. 9B is a top view of the speaker, resilient layer, and wall preliminary to assembly. Although a round-shaped speaker is illustrated, the sliding-tab approach may also be adapted for rectangular and other geometries. Wall 912 has wall tabs 922 raised above an aperture shoulder and spaced at intervals. The intervals between wall tabs 922 are large enough to accommodate speaker tabs 926 extending out from speaker 916 . Resilient layer 951 covers at least the part of the aperture shoulder that contacts the front perimeter of speaker 916 .
[0065] FIG. 9C is a cutaway side view of the assembly shown in FIG. 9B . With the parts simply laid over one another and resilient layer 951 uncompressed, wall tab 922 does not appear to have sufficient clearance for speaker tab 926 extending from speaker 916 .
[0066] FIG. 9D is the same assembly with the tabs engaged. The speaker was moved (in the case of the illustrated round speaker, rotated) in direction 910 relative to wall 912 . To make room for speaker tab 926 under wall tab 922 , resilient layer 951 is compressed. The compression enables resilient layer 951 to provide (1) a tight seal to confine air in the back volume and (2) a restoring force to stabilize the joint. As illustrated, speaker tab 926 and wall tab 922 have a plane contact, held together by the restoring force of compressed resilient layer 951 and by stiction between the two contacting surfaces. Stiction can be enhanced by roughening the contacting surfaces to, e.g., an rms roughness of 0.05-0.3 mm.
[0067] The restoring force from compressed resilient layer 951 pushes speaker 916 upward, Wall tab 922 exerts a downward counterforce on the underlying portion of speaker tab 926 . As a result, speaker tabs 926 may be subject to shear stress at the inner edge of the overlap where the downward counterforce ends, as well as compressive stress within the overlap zone. In some embodiments, speaker tabs 926 are as resistant to damage by shear and compression, at least within an order of magnitude, as the outer frame or basket of speaker 916 .
[0068] FIGS. 10A-G illustrate more views and examples of sliding-tab sealing assemblies.
[0069] FIG. 10A is a top view of sliding-tab seal parts for a circular audio speaker. Wall 1012 A includes wall tabs 1022 A. Between wall tabs 1022 A are cutouts to accommodate speaker tabs 1026 A, which extend out from speaker 1016 A. Between speaker 1016 A and wall 1012 A is resilient layer 1051 A. Resilient layer 1051 A and speaker 1016 A rest on a ring-shaped shoulder recessed into wall 1012 A and surrounding speaker aperture 1062 A by which the sound from the speaker exits the parent device. In this view, the hidden line defines the edge of speaker aperture 1062 A. To seal speaker 1016 A to wall 1012 A, speaker 1016 A is rotated in one of motion directions 1010 A to slide (and optionally lock) speaker tabs 1026 A under wall tabs 1022 A. Section A-A roughly corresponds to the views in FIGS. 9A , C, and D: along a roughly tangential line that does not intersect speaker aperture 1062 A. Section B-B roughly corresponds to the view in FIG. 10C : along a roughly radial line that does intersect speaker aperture 1062 A.
[0070] FIG. 10B is a top view of sliding-tab seal parts for a rectangular audio speaker. Wall 1012 B includes wall tabs 1022 B. Between wall tabs 1022 B are spaces to accommodate speaker tabs 1026 B, which extend out from speaker 1016 B. Between speaker 1016 B and wall 1012 B is resilient layer 1051 B. Resilient layer 1051 B and speaker 1016 B rest on a rectangular shoulder recessed into wall 1012 B and surrounding speaker aperture 1062 B by which the sound from the speaker exits the parent device. In this view, some of speaker aperture 1062 B is visible because speaker 1016 B has not yet been slid into place/To seal speaker 1016 B to wall 1012 B, speaker 1016 B is pushed or pulled in motion direction 1010 B to slide (and optionally lock) speaker tabs 1026 B under wall tabs 1022 B.
[0071] FIGS. 10C-10E are cross-sections through either A-A or B-B of FIG. 10A , illustrating different snap-locking designs. The snap-lock added to the sliding tabs holds the tabs in place, allowing looser tolerances than a friction fit, and provides an audible or tactile “click,” which may be sensed by human or some robotic assemblers, when the tabs are overlapped and locked correctly.
[0072] In FIG. 10C , wall tab 1022 . 1 has an approximately conical bump 1042 . 1 . Speaker tab 1026 . 1 has a complementary recess 1046 . 1 into which conical bump 1042 . 1 clicks. The same cross-section also represents an embodiment in which 1042.1 is a V-shaped ridge extending in and out of the page and 1046 . 1 is a corresponding parallel groove.
[0073] In FIG. 10D , wall tab 1022 . 2 has a downward-extending latch 1042 . 2 . Speaker tab 1026 . 2 has a complementary upward-extending latch 1046 . 2 into which downward-extending latch 1042 . 2 clicks.
[0074] In FIG. 10E , wall tab 1022 . 3 has a spherical bump 1042 . 3 . As illustrated, spherical bump 1042 . 3 is spring-loaded, but the spring may be omitted if the resiliency of the resilient layer (not shown in this view) is high enough to make the spring unnecessary. Speaker tab 1026 . 3 has a complementary hole 1046 . 3 into which spherical bump 1042 . 3 clicks.
[0075] FIG. 10F is a sectional view through section B-B of FIG. 10A illustrating another way to arrange the wall tabs. In FIGS. 9A-D , the leading edge of speaker tab 926 slides toward wall tab standoff 932 when the speaker is rotated or translated in the locking direction. In FIG. 10F , the leading edge of speaker tab 926 slides past wall tab standoff 1032 when the speaker is rotated or translated in the locking direction. As illustrated, speaker 1016 is rotated relative to wall 1012 to slide speaker tab 1026 under wall tab 1022 . Speaker aperture 1062 and wall shoulder 1072 are visible in this view.
[0076] FIG. 10G is an illustration of an embodiment of the ball-and-hole latch of FIG. 10E through section A-A of FIG. 10A . Top surface S of speaker tab 1026 . 4 may be tapered in one or more places that may become leading edge(s) for the sliding tabs, to make it smoother and easier to slide speaker tab 1026 . 4 under the latch portion of wall tab 1022 . 4 . Although the illustration shows a ball-and-hole latch, the technique may also be used with other latch designs.
[0077] FIGS. 11A-11D are perspective views of examples of tabbed speaker parts and assemblies.
[0078] FIG. 11A is a perspective view of a tabbed integrated front piece of a round speaker. The single piece includes diaphragm 1103 , speaker tab 1126 . 1 , and ridge 1136 that may be used to position the opening of a gasket or O-ring.
[0079] FIG. 11B is a perspective view of the back of a tabbed round speaker. Around the edges of basket 1107 . 1 are speaker cog teeth 1124 . Installation tool 1110 has complementary tool cog teeth 1120 . The tabbed speaker can be installed from the back, either manually or automatically, by meshing tool cog teeth 1120 with speaker cog teeth 1124 , pushing down to compress the gasket, O-ring, or other resilient layer (not shown in this view), and twisting to move speaker tabs 1126 . 2 under the corresponding wall tabs (not shown in this view).
[0080] As illustrated, the speaker has the same number of cog teeth 1124 as speaker tab 1126 . 2 , and cog teeth 1124 are aligned to speaker tab 1126 . 2 . Neither of these is necessary for the general approach to function; the numbers may be different, and the alignment is arbitrary.
[0081] FIG. 11C is a perspective view of the back of a tabbed rectangular speaker. Speaker tabs 1126 . 3 extending out from frame 1114 have notches N for a clicking feedback when speaker tab 1126 . 3 are slid under the corresponding wall tabs (not shown in this view) to the desired position. Front tab F (for the explanation of this figure, “front” is temporarily redefined as “the direction in which the speaker slides into place”) is optional for some embodiments.
[0082] Alternatively, the speaker could be positioned by a click-notch in front tab F, with the side tabs having a smooth top surface. That notch may be oriented in the same absolute direction as notches N, which would make it a lengthwise notch in tab F, compared to crosswise notches N in the side tabs.
[0083] A tool analogous to tool 1110 in FIG. 11B could be used to install the speaker of FIG. 11C by meshing with the corner cutouts of baskets 1107 . 2 and 1107 . 3 , pushing down to compress the resilient layer (not shown in this view), and sliding the speaker in a straight line rather than rotating it.
[0084] FIG. 11D is a perspective view of the back of an installed rectangular speaker on a parent-device wall 1102 . The speaker in this example has a single basket 1107 . 4 . Clamp tabs 1122 extend from raised lip 1112 to grasp and hold the edges of frame 1114 .
[0085] Materials for speaker covers, frames, and baskets include hard, rigid plastics and lightweight metals such as aluminum and magnesium. Materials for resilient layers include elastomers and other elastically compressible materials.
[0086] The preceding Description and accompanying Drawings describe examples of embodiments in some detail to aid understanding. However, the scope of protection may also include equivalents, permutations, and combinations that are not explicitly described herein. Only the appended claims (along with those of parent, child, or divisional patents, if any) define the limits of the protected intellectual-property rights.
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Small-scale audio speakers of various shapes are installed in parent devices. Inner casings, and the surrounding vibration-damping zone often required between such casings and the surrounding parent-device walls, are omitted from the assembly. During integration with the parent device, each un-encased speaker and its signal lines are sealed into a single-walled enclosure that incorporates a parent-device wall as at least one side. The entire interior of the single-walled enclosure becomes a back volume for the speaker. The single-walled enclosure may incorporate seals at the speaker's audio-output aperture, at the pass-through for the signal lines, and at the interface between the parent-device wall(s) and the added side(s) constituting the single-walled enclosure. Optional adhesive-free sealing options include sliding tabs held by a snap-lock latch.
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This application is a continuation of application Ser. No. 08/515,216, filed Aug. 15, 1995, now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an image forming apparatus provided with a detachable process unit.
2. Description of the Related Art
In an image forming apparatus such as a copying apparatus, it has been considered to attach a memory on an interchangeable process unit such as a drum unit and to judge the service life thereof from the content stored in the memory, such as the number of copies. However, if the process unit which is judged to have reached the end of the service life is merely replaced by a new process unit, the image forming conditions may be varied and the image may not be obtained in the optimum condition.
It is therefore conceivable to store, in the memory of the process unit, process conditions specific to the process unit and, when the process unit is mounted on the image forming apparatus, to automatically feed the process conditions into a memory of the apparatus itself or to execute a mode for measuring the image forming conditions, thereby determining the process conditions.
It is however cumbersome and time consuming to execute such measurement mode for the image forming conditions at each replacement of the process unit, and the appropriate image cannot be obtained without the execution of such mode.
Also in case of storing the number of copies in the memory of the process unit at every copying operation, it is necessary to confirm whether the copy count has been stored, but such confirmation, if conducted after the completion of the copying operation, cannot be made in case the power supply is turned off immediately after the copying operation.
It is also necessary to consider the countermeasure against improper tampering of the data stored in the memory of the process unit.
SUMMARY OF THE INVENTION
In consideration of the foregoing, an object of the present invention is to provide an image forming apparatus that overcomes the above-mentioned drawbacks.
Another object of the present invention is to provide an image forming apparatus for which the user or the service personnel is not required, at each replacement of the process unit, to cause the apparatus to read the process conditions specific to the process unit or to execute the measurement mode for determining the image forming conditions.
Still another object of the present invention is to provide an image forming apparatus capable of inhibiting the image forming operation based on improperly tampered with data of the data stored in the memory of the process unit.
Still another object of the present invention is to provide an image forming apparatus that allows it to easily be judged whether the deterioration in the image quality is caused by the process unit or by the image forming apparatus itself.
Still another object of the present invention is to provide an image forming apparatus wherein the timing of replacement of the process unit is allowed to be known.
Still other objects of the present invention, and the features thereof, will become fully apparent from the following description to be taken in conjunction with the attached drawings, and from the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross-sectional view of an image forming apparatus;
FIG. 2 is a block diagram of a control unit of the image forming apparatus;
FIG. 3 is a schematic view of data stored in a non-volatile memory 104;
FIG. 4 is a table showing operation codes of the non-volatile memory 104;
FIGS. 5A, 5B and 5C are timing charts of three modes (data read-out, data write-in and data erasure);
FIG. 6 is a flow chart showing a copying routine;
FIG. 7 is a flow chart showing a data reading subroutine of the non-volatile memory;
FIG. 8 is a flow chart showing a process cartridge setting subroutine; and
FIG. 9 is a flow chart of a measurment made subroutine.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Now the image forming apparatus of the present invention will be clarified in detail by an embodiment thereof, applied to a copying apparatus, of which a cross-sectional view is shown in FIG. 1.
There are shown a main body 1 of the copying apparatus; an original pressure plate 2; an original supporting glass plate 3; an exposure lamp 4; mirrors 5-7 and 9-11; a lens 8; a sheet feeding roller 17; transport rollers 18, 19; a transport unit 20; a fixing unit 21; sheet discharge rollers 22; and a sheet discharge tray 49.
The driving system consists of a main driving system for driving a sheet feeding unit, a sheet transporting unit, a photosensitive member and a fixing unit, and an optical driving system for driving an optical system constituting a load. The main driving system employs a DC brushless motor 25, while the optical system employs a stepping motor 26. In the optical driving system, phase energization signals are generated for supply to the different phases of the stepping motor 26. In the present embodiment, the stepping motor 26 is switched between the 2-phase driving method and the 1-2 phase driving method according to the velocity information set on the load.
The sheet feeding can be made either from a cassette 23 or from a multiple hand-feed tray unit In case of sheet feeding from the cassette 23, the sheet feeding state is controlled by a switch for detecting the presence or absence of the cassette 23, a switch group 31 for detecting the size of the cassette 23 and a switch 37 for detecting the presence or absence of sheet in the cassette 23, and, in case an abnormality is detected by these switches, a corresponding message is displayed on a display unit.
In case of multiple hand-feed sheet feeding, the sheet feeding state is controlled by a switch for detecting the state of the hand-feed unit 24, and, upon detection of an abnormality, a corresponding message is displayed on the display unit.
A photosensitive member 12 rotates clockwise in the drawing. It is charged by a primary charger 13 and then exposed in an exposure position to form a latent image, which is developed with toner by a developing unit 15, and the obtained toner image is transferred, in a transfer unit 14, onto a recording sheet supplied from the sheet feeding unit. After the toner image transfer, the photosensitive member 12 is subjected to the removal of remaining toner by a cleaning unit 38, then the elimination of retentive potential by a pre-exposure lamp 16, and is used again in the image forming process. The recording sheet, bearing the transferred toner image, is transported to a fixing unit 21 by a conveyor belt of a transport unit 20. A process cartridge 39, including the photosensitive member 12, the primary charger 13 and the cleaning unit 38, is detachably mounted on the copying apparatus 1.
The fixing unit 21 is provided with a drive roller 35, a tension roller 45 and a pressure roller 44.
A heater 43 of the fixing unit 21 is formed by printing a resistance member on a ceramic substrate, and has terminals at an end. The heater 43 is supported by a heat-resistant plastic supporter 42, on which a metal stay is mounted. An endless film 47 is provided around the drive roller 35, the tension roller 45 and the heater 43.
A temperature detecting element (thermistor) 41 is mounted on the metal stay and is in direct contact with the rear face of the heater 43. Another temperature detecting element 48 is similarly mounted on the rear face of the heater 43. This temperature detecting element 48 is positioned at an end of the heater 43 and is used for detecting the temperature of a sheet-free portion in case small-sized sheets are passed and expanding the gap between the sheets, because the temperature in such sheet-free portion becomes higher in case of such small-sized sheets.
The heater unit consisting of the heater 43, the plastic supporter 42 and the metal stay, and the endless film 47 are pressurized by the pressure roller 44.
FIG. 2 is a block diagram showing the configuration of a control unit of the copying apparatus constituting the image forming apparatus, wherein shown are a controller 101 for receiving signals from various sensors provided in the copying apparatus and controlling the functions of various loads such as the DC brushless motor and the stepping motor; a SRAM 102 for storing process conditions required for image formation, recovery information in case of sheet jamming, back-up information in case of a machine error, etc.; an operation unit 103 for setting the copy mode; and a non-volatile memory (EEPROM) 104 incorporated in the process cartridge 39 (including the photosensitive member 12, the primary charger 13 and the cleaner 38).
When the process cartridge 39 is mounted on the main body, the non-volatile memory 104 incorporated therein is automatically connected, by a drawer connector, to the controller 101. FIG. 3 illustrates the data stored in the non-volatile memory 104, wherein data of 16 bits are stored for each address as shown in the following:
______________________________________Addresses 0-1 serial numbers 00XXXXXXHAddress 2 counter value XXXXHAddress 3 process condition 1 XXXXHAddress 4 process condition 2 XXXXHAddresses 5-63 vacant FFFFH______________________________________
The process conditions 1 and 2 are used for varying the high voltage condition at the image formation, according to the fluctuation in the sensitivity of the photosensitive drum 12 in the process cartridge 39. The serial number is given to each process cartridge 39 and consists of 2 words (4 bytes), with uppermost bits always starting with "00". Each of the empty addresses 5-63 stores "FFFFH". The counter value is increased by one at each copying operation.
The read-out and write-in operations of the non-volatile memory (EEPROM) 104 are conducted in the following manner. FIG. 4 shows the operation codes of the non-volatile memory 104, and FIGS. 5A to 5C show the timing charts for three modes (data read-out, data write-in and data erasure). A symbol CS stands for chip select; SK for clock; DI for operation code and address input; and DO for data output.
A DI port fetches the operation code and the address supplied in synchronization with the upshift of a clock signal. A DO port releases data in synchronization with the upshift of a clock signal. Seven modes are realized by the combinations of the operation codes and the addresses.
As the photosensitive drum 12 in the process cartridge 39 shows fluctuation in sensitivity, the correction value for the sensitivity is measured for each process cartridge 39, and the measured correction value is stored as the process conditions 1 and 2 in the non-volatile memory 104. Also 0 is written as the counter value of the address 2, at a timing shown in FIG. 5B. Thus, the content of the non-volatile memory 104 is set in the following manner, at the initial shipment from the factory:
______________________________________Addresses 0-1 serial number serially numbered from 1Address 2 counter value 0Address 3 process condition 1 -10 to 10Address 4 process condition 2 -63 to 63______________________________________
In the following there will be explained the function at the copying operation, with reference to a flow chart shown in FIG. 6. When the process cartridge 39 is newly mounted on the image forming apparatus and the power supply is turned on, the controller 101 of the image forming apparatus reads the content of the non-volatile memory 104 of the process cartridge 39 (step S200).
FIG. 5A is a timing chart of a read-out mode for reading the data stored in the memory of the process cartridge 39. At first the controller 101 sends, to the DI port, data "110" (first bit 1 being a dummy code, second and third bits constituting an operation code) indicating the read-out mode, followed immediately by an address (A0-A5) to be read. Then data (D15-D0) of the designated address are read from the memory and transferred, through the D0 port, to the controller 101.
FIG. 5B is a timing chart of a data write-in mode for storing the process condition or the count value into the memory of the process cartridge 39. In case of storing a copy count, the controller 101 sends, to the DI port, data "101" indicating the data write-in mode, immediately followed by a write-in address (A0-A5) and data (D0-D15) to be written.
FIG. 5C is a timing chart of a data erasure mode for erasing the data stored in the memory of the process cartridge 39. At first the controller 101 releases data "111" indicating the data erasure mode, immediately followed by an address (A0-A5) to be erased, whereby the data of the designated address are erased.
FIG. 7 is a flow chart showing a data reading subroutine of the non-volatile memory.
In this subroutine, there is discriminated whether the uppermost bit of the serial number in the addresses 0-1 is equal to "0" (step S221), and, if equal, there is further discriminated whether the content of the unused addresses 5-63 is "FFH" (step S222). If it is "FFH", the process conditions 1 and 2 of the non-volatile memory 104 are stored in the SRAM 102 of the main body (step S223) and the sequence returns to the main routine.
On the other hand, if the uppermost bit of the serial number is not "0" or if the content of the unused addresses is not "FFH". The copying operation is inhibited (step S224). In such situation, the content of the non-volatile memory is identified as improperly tampered with and altered.
After the data reading from the non-volatile memory 104, a count stored in advance in the SRAM 102 of the main body is compared with the count stored in the non-volatile memory 104 (said count being called drum counter) (steps S201, S202), and, if these counts are mutually equal and are not zero, a measurement mode is executed (step S203). FIG. 9 is a flow chart of a measurement mode subroutine. In the measurement mode, the primary output voltage of the process cartridge 39 is determined by charging the drum 12 with a predetermined primary voltage from the primary charger 13 and measuring the current from the drum 12. The primary output voltage thus determined is memorized in the SRAM 102 of the image forming apparatus. The SRAM 102 stores the primary output voltages determined in the past three measurement mode cycles, and an appropriate primary output voltage is determined as the average of the four primary output voltages (steps S241-S246). Thereafter the controller enters a waiting state for the actuation of the copy key (step S205). If the two counts do not mutually coincide or if they are both zero, the sequence proceeds to a process cartridge setting mode (step S204).
FIG. 8 is a flow chart showing a process cartridge setting mode subroutine. In this mode, an appropriate primary output voltage in the process cartridge 39 is determined by charging the drum 12 with a predetermined primary voltage from the primary charger 13 and by measuring the current from the drum 12 (steps S235-S239). The primary output voltage is determined by repeating the measurement four times and taking the average. Then the count in the main body is set equal to the count of the drum counter (step S240), and the present subroutine is terminated.
When the copy key is actuated, the sheet feeding is executed (step S206), then the count of the drum counter is read (step S207) and compared with the count in the main body (step S208). This comparison is conducted in order to confirm whether the count of the drum counter has been properly renewed at the preceding copying operation. If both counts mutually coincide, a copying operation is executed (step S209), then the counts of the main body and of the drum counter are respectively increased by one (step S210) and the sequence returns to the step S205.
If the counts do not mutually coincide, a write-in error in the process cartridge 39 is identified and the copying operation is therefore inhibited (step S211).
It is also possible to store the appropriate primary output voltage, determined in the process cartridge setting mode, in the SRAM 102, and, in case the discrimination of the step S202 is negative, to adopt the appropriate primary output voltage stored in the SRAM 102 without execution of the measurement mode.
The present invention is not limited to the foregoing embodiment but is subjected to various modifications within the scope and spirit of the appended claims.
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An image forming apparatus such as a copier with a detachable process cartridge is provided with a first memory for storing the number of copying operations; a count renewing unit for increasing the count of the first memory and a second memory in the process cartridge, at each copying operation, a comparator for comparing the counts in the first and second memories, and a controller for determining a process condition specific to the process cartridge in case the counts do not mutually coincide. The service life of the process cartridge can be more precisely judged, and the process condition can be more appropriately determined for each process cartridge.
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CROSS-REFERENCE TO RELATED APPLICATION
This application claims the benefit of U.S. provisional application Serial No. 60/349,310, filed Jan. 15, 2002, which is incorporated herein by reference.
FIELD OF THE INVENTION
This invention relates to a novel crystalline solid of carvedilol or a solvate thereof, to processes for its preparation, to compositions containing it and to its use in medicine. This invention further relates to a novel process for preparing crystalline carvedilol Form II.
BACKGROUND OF THE INVENTION
Carvedilol, (±)-1-(Carbazol-4-yloxy)-3-[[2-(o-methoxyphenoxy) ethyl]amino]-2-propanol, is a nonselective β-adrenergic blocker with α 1 -blocking activity. Carvedilol is a racemic mixture having the following structural formula:
Carvedilol is the active ingredient of COREG®, which is indicated for the treatment of congestive heart failure and for the management of hypertension. Since carvedilol is a multiple-action drug, its beta-blocking activity affects the response to certain nerve impulses in parts of the body. As a result, beta-blockers decrease the heart's need for blood and oxygen by reducing its workload. Carvedilol is also known to be a vasodilator resulting primarily from alpha-adrenoceptor blockade. The multiple actions of carvedilol are responsible for the antihypertensive efficacy of the drug and for its effectiveness in managing congestive heart failure.
International application No. WO 99/05105 (the '105 application) discloses that carvedilol can be isolated in two polymorphic forms, depending on the method of preparation. The two polymorphic forms, designated Form I and Form II, are reported to be monotropic and are distinguishable by their infrared, Raman and powder X-ray diffraction (PXRD) spectra. No evidence is found in the literature about the existence of solvate forms of carvedilol.
In Example 1 of the '105 application, Form I was generated by dissolving crude carvedilol in methanol, heating the solution, cooling the solution, and stirring the solution for a time sufficient to produce Form I. Form II was generated by recrystallizing Form I in 2-propanol.
The present invention relates to the solid state physical properties of carvedilol. These properties can be influenced by controlling the conditions under which carvedilol is obtained in solid form. Solid state physical properties include, for example, the flowability of the milled solid. Flowability affects the ease with which the material is handled during processing into a pharmaceutical product. When particles of the powdered compound do not flow past each other easily, a formulation specialist must take that fact into account in developing a tablet or capsule formulation, which may necessitate the use of glidants such as colloidal silicon dioxide, talc, starch or tribasic calcium phosphate.
Another important solid state property of a pharmaceutical compound is its rate of dissolution in aqueous fluid. The rate of dissolution of an active ingredient in a patient's stomach fluid can have therapeutic consequences since it imposes an upper limit on the rate at which an orally-administered active ingredient can reach the patient's bloodstream. The rate of dissolution is also a consideration in formulating syrups, elixirs and other liquid medicaments. The solid state form of a compound may also affect its behavior on compaction and its storage stability.
These practical physical characteristics are influenced by the conformation and orientation of molecules in the unit cell, which defines a particular polymorphic form of a substance. The polymorphic form may give rise to thermal behavior different from that of the amorphous material or another polymorphic form. Thermal behavior is measured in the laboratory by such techniques as capillary melting point, thermogravimetric analysis (TGA) and differential scanning calorimetric (DSC) and can be used to distinguish some polymorphic forms from others. A particular polymorphic form may also give rise to distinct spectroscopic properties that may be detectable by powder X-ray crystallography, solid state 13 C NMR spectrometry and infrared spectrometry.
The present invention also relates to solvates of carvedilol. When a substance crystallizes out of solution, it may trap molecules of solvent at regular intervals in the crystal lattice. Solvation also affects utilitarian physical properties of the solid state like flowability and dissolution rate.
One of the most important physical properties of a pharmaceutical compound, which can form polymorphs or solvates, is its solubility in aqueous solution, particularly the solubility in gastric juices of a patient. Other important properties relate to the ease of processing the form into pharmaceutical dosages, such as the tendency of a powdered or granulated form to flow and the surface properties that determine whether crystals of the form will adhere to each other when compacted into a tablet.
The discovery of new polymorphic forms and solvates of a pharmaceutically useful compound provides a new opportunity to improve the performance characteristics of a pharmaceutical product. It enlarges the repertoire of materials that a formulation scientist has available for designing, for example, a pharmaceutical dosage form of a drug with a targeted release profile or other desired characteristic. A new polymorphic form and solvate of carvedilol has been discovered.
SUMMARY OF THE INVENTION
In one aspect, the present invention provides a crystalline solid of carvedilol or a solvate thereof characterized by data selected from the group consisting of a PXRD pattern with peaks at about 6.5, 7.3, 16.0, and 30.5±0.2 degrees two-theta, a PXRD pattern with peaks at about 5.8, 10.7, 11.1, 11.5, 13.1, 13.7, 16.8, 17.7, 18.5, and 23.0±0.2 degrees two-theta, a DSC thermogram with endothermic peaks at about 74° C. and 112° C., and a FTIR spectrum with peaks at about 613, 740, 994, 1125, 1228, 1257, 1441, 1508, 1737, 2840, 3281, 3389, and 3470 cm −1 . Said solid crystalline form denotes Form VI.
In another aspect, the present invention provides a process for preparing a crystalline solid of carvedilol or a solvate thereof having at least one characteristic of Form VI (such as the PXRD peaks and/or FTIR peaks, and/or DSC peaks disclosed herein). In accordance with the process, carvedilol is contacted with ethyl acetate to form a solution. The solution is cooled and optionally seeded with carvedilol Form II. The solution can be stirred under high velocity agitation to form a suspension, which then can be cooled under high velocity agitation.
In yet another aspect, the present invention provides a process for preparing a crystalline solid of carvedilol Form II, including the steps of heating crystalline carvedilol having at least one characteristic of Form VI until the crystalline carvedilol is dry, mixing carvedilol Form II with the dry crystalline carvedilol, and storing the mixture for a holding time sufficient to transform the dry crystalline carvedilol into Form II.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 is a PXRD pattern for carvedilol Form VI.
FIG. 2 is a FTIR spectrum for carvedilol Form VI.
FIG. 3 is a DSC thermogram for carvedilol Form VI.
FIG. 4 is a DTG thermogram for carvedilol Form VI.
DETAILED DESCRIPTION OF THE INVENTION
In one aspect, the present invention provides a novel crystalline solid of carvedilol or a solvate thereof, designated Form VI. Carvedilol solvate Form VI is characterized by a PXRD pattern (FIG. 1) with peaks at about 6.5, 7.3, 16.0, and 30.5±0.2 degrees two-theta. Further PXRD peaks were observed at about 5.8, 10.7, 11.1, 11.5, 13.1, 13.7, 16.8, 17.7, 18.5, and 23.0±0.2 degrees two-theta.
Carvedilol solvate Form VI produces a FTIR spectrum (FIG. 2) with characteristic absorption bands at about 613, 740, 994, 1125, 1228, 1257, 1441, 1508, 1737, 2840, 3281, 3389, and 3470 cm −1 . Further FTIR peaks were observed at about 720, 1100, 1286, 1454, 1589, 2911, and 2935 cm −1 .
Carvedilol solvate Form VI produces a DSC thermogram (FIG. 3) showing two endothermic peaks: the main endothermic peak was observed at about 74° C. and a minor endotherm (dH=0.7J/g) was observed at 112° C.
Carvedilol solvate Form VI produces a Differential Thermal Gravimetry (DTG) thermogram (FIG. 4) showing a weight loss step in the temperature range of 35-104° C. of about 13%. This value is equal to the expected value corresponding to two molecules of ethyl acetate per three molecules of carvedilol.
The water content of carvedilol solvate Form VI was tested by Karl-Fisher titration, which showed it to be free of water.
In another aspect, the present invention provides a novel process for preparing a crystalline solid of carvedilol or a solvate thereof, involving the steps of contacting carvedilol with ethyl acetate to form a solution, cooling the solution optionally under agitation. Preferably, the starting carvedilol is dry. The solution can optionally be seeded with carvedilol Form II. The solution can be stirred under high velocity agitation to form a suspension, which then can be cooled under high velocity agitation. The product obtained by this process has at least one characteristic of Form VI, and can be separated from the ethyl acetate by conventional means such as filtration. The product can also be dried.
Preferably, the mixture of ethyl acetate and dry carvedilol is heated to a temperature in the range of about 65° to about 80° C., most preferably in the range of about 70° to about 77° C. to form a solution. Thereafter, preferably, the temperature of the solution is reduced to between about 40° to about 55° C., most preferably between about 46° to about 50° C.
When the solution is seeded with carvedilol Form II, the seeded solution is stirred at a temperature in the range of about 46° C. to about 50° C. for a holding time sufficient to precipitate Form VI. A holding time of about 30 minutes under high velocity agitation (at least 260 rpm) is typically sufficient. Thereafter, the temperature of the suspension is preferably cooled to about 10° C. for a holding time, preferably about 3 hours under high velocity agitation. The cooled suspension should be stirred for about 30 minutes.
In another aspect, the present invention provides a process for preparing a crystalline solid of carvedilol Form II, including the steps of heating crystalline carvedilol having at least one characteristic of Form VI until the crystalline carvedilol is dry, mixing carvedilol Form II with the dry crystalline carvedilol, and storing the mixture for a holding time sufficient to transform the dry crystalline carvedilol into Form II.
Preferably, crystalline carvedilol having at least one characteristic of Form VI is heated to a temperate in the range of about 50° to about 60° C., and most preferably to about 55° C. The heating step can be preformed at atmospheric pressure or under reduced pressure. Preferably, the pressure is about 60 mm Hg, and more preferably about 30 mm Hg. Crystalline carvedilol having at least one characteristic of Form VI is typically dry after about 16 hours of heating.
Dry crystalline carvedilol having at least one characteristic of Form VI is mixed with carvedilol Form II and stored for a holding time sufficient to transform the dry crystalline carvedilol into Form II. A holding time of from about 1 week to about 2 weeks is typically sufficient. Carvedilol Form I can also be present.
Carvedilol Form VI can be milled into a powder and used in a pharmaceutical product or physically modified such as by granulation to produce larger granules of carvedilol Form VI. Carvedilol Form VI can also be used to prepare a liquid pharmaceutical product by dissolving or dispersing it in a liquid medium such as water, glycerin, vegetable oil and the like as discussed in greater detail below.
Carvedilol Form VI is useful for treating patients with congestive heart failure and hypertension and for producing a hypotensive effect in mammals, including human patients. Carvedilol Form VI can be formulated into a variety of compositions for administration to humans and mammals.
Pharmaceutical compositions of the present invention contain carvedilol Form VI, optionally in mixture with other crystalline forms and/or other active ingredients such as hydrochlorothiazide. In addition to the active ingredient(s), the pharmaceutical compositions of the present invention can contain one or more excipients. Excipients arc added to the composition for a variety of purposes.
Diluents increase the bulk of a solid pharmaceutical composition and can make a pharmaceutical dosage form containing the composition easier for the patient and caregiver to handle. Diluents for solid compositions include, for example, microcrystalline cellulose (e.g. Avicel®), microfine cellulose, lactose, starch, pregelatinized starch, calcium carbonate, calcium sulfate, sugar, dextrates, dextrin, dextrose, dibasic calcium phosphate dihydrate, tribasic calcium phosphate, kaolin, magnesium carbonate, magnesium oxide, maltodextrin, mannitol, polymethacrylates (e.g. Eudragit®), potassium chloride, powdered cellulose, sodium chloride, sorbitol and talc.
Solid pharmaceutical compositions that are compacted into a dosage form like a tablet can include excipients whose functions include helping to bind the active ingredient and other excipients together after compression. Binders for solid pharmaceutical compositions include acacia, alginic acid, carbomer (e.g. carbopol), carboxymethylcellulose sodium, dextrin, ethyl cellulose, gelatin, guar gum, hydrogenated vegetable oil, hydroxyethyl cellulose, hydroxypropyl cellulose (e.g. Klucel®), hydroxypropyl methyl cellulose (e.g. Methocel®), liquid glucose, magnesium aluminum silicate, maltodextrin, methylcellulose, polymethacrylates, povidone (e.g. Kollidon®, Plasdone®), pregelatinized starch, sodium alginate and starch.
The dissolution rate of a compacted solid pharmaceutical composition in the patient's stomach can be increased by the addition of a disintegrant to the composition. Disintegrants include alginic acid, carboxymethylcellulose calcium, carboxymethylcellulose sodium (e.g. Ac-Di-Sol®, Primellose®), colloidal silicon dioxide, croscarmellose sodium, crospovidone (e.g. Kollidon®, Polyplasdone®), guar gum, magnesium aluminum silicate, methyl cellulose, microcrystalline cellulose, polacrilin potassium, powdered cellulose, pregelatinized starch, sodium alginate, sodium starch glycolate (e.g. Explotab®) and starch.
Glidants can be added to improve the flow properties of non-compacted solid composition and improve the accuracy of dosing. Excipients that can function as glidants include colloidal silicon dioxide, magnesium trisilicate, powdered cellulose, starch, talc and tribasic calcium phosphate.
When a dosage form such as a tablet is made by compaction of a powdered composition, the composition is subjected to pressure from a punch and dye. Some excipients and active ingredients have a tendency to adhere to the surfaces of the punch and dye, which can cause the product to have pitting and other surface irregularities. A lubricant can be added to the composition to reduce adhesion and ease release of the product form the dye. Lubricants include magnesium stearate, calcium stearate, glyceryl monostearate, glyceryl palmitostearate, hydrogenated castor oil, hydrogenated vegetable oil, mineral oil, polyethylene glycol, sodium benzoate, sodium lauryl sulfate, sodium stearyl fumarate, stearic acid, talc and zinc stearate.
Flavoring agents and flavor enhancers make the dosage form more palatable to the patient. Common flavoring agents and flavor enhancers for pharmaceutical products that can be included in the composition of the present invention include maltol, vanillin, ethyl vanillin, menthol, citric acid, fumaric acid, ethyl maltol, and tartaric acid.
Solid and liquid compositions can also be dyed using any pharmaceutically acceptable colorant to improve their appearance and/or facilitate patient identification of the product and unit dosage level.
In liquid pharmaceutical compositions of the present invention, carvedilol Form VI and any other solid excipients are dissolved or suspended in a liquid carrier such as water, vegetable oil, alcohol, polyethylene glycol, propylene glycol or glycerin.
Liquid pharmaceutical compositions can contain emulsifying agents to disperse uniformly throughout the composition an active ingredient or other excipient that is not soluble in the liquid carrier. Emulsifying agents that can be useful in liquid compositions of the present invention include, for example, gelatin, egg yolk, casein, cholesterol, acacia, tragacanth, chondrus, pectin, methyl cellulose, carbomer, cetostearyl alcohol and cetyl alcohol.
Liquid pharmaceutical compositions of the present invention can also contain a viscosity-enhancing agent to improve the mouth-feel of the product and/or coat the lining of the gastrointestinal tract. Such agents include acacia, alginic acid bentonite, carbomer, carboxymethylcellulose calcium or sodium, cetostearyl alcohol, methyl cellulose, ethylcellulose, gelatin guar gum, hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxypropyl methyl cellulose, maltodextrin, polyvinyl alcohol, povidone, propylene carbonate, propylene glycol alginate, sodium alginate, sodium starch glycolate, starch tragacanth and xanthan gum.
Sweetening agents such as sorbitol, saccharin, sodium saccharin, sucrose, aspartame, fructose, mannitol and invert sugar can be added to improve the taste.
Preservatives and chelating agents such as alcohol, sodium benzoate, butylated hydroxy toluene, butylated hydroxyanisole and ethylenediamine tetraacetic acid can be added at levels safe for ingestion to improve storage stability.
A liquid composition according to the present invention can also contain a buffer such as guconic acid, lactic acid, citric acid or acetic acid, sodium guconate, sodium lactate, sodium citrate or sodium acetate.
Selection of excipients and the amounts to use can be readily determined by the formulation scientist based upon experience and consideration of standard procedures and reference works in the field.
The solid compositions of the present invention include powders, granulates, aggregates and compacted compositions.
Carvedilol Form VI can be administered for treatment of congestive heart failure and hypertension by any means that delivers the active ingredient(s) to the site of the body where beta-blocking activity exerts a therapeutic effect on the patient. For example, administration can be oral, buccal, parenteral (including subcutaneous, intramuscular, and intravenous) rectal, inhalant and ophthalmic. Although the most suitable route in any given case will depend on the nature and severity of the condition being treated, the most preferred route of the present invention is oral. Carvedilol Form VI can be conveniently administered to a patient in oral unit dosage form and prepared by any of the methods well-known in the pharmaceutical arts. Dosage forms include solid dosage forms like tablets, powders, capsules, sachets, troches and lozenges as well as liquid syrups, suspensions and elixirs.
The active ingredient(s) and excipients can be formulated into compositions and dosage forms according to methods known in the art.
A composition for tableting or capsule filing can be prepared by wet granulation. In wet granulation some or all of the active ingredients and excipients in powder form are blended and then further mixed in the presence of a liquid, typically water, that causes the powders to clump up into granules. The granulate is screened and/or milled, dried and then screened and/or milled to the desired particle size. The granulate can then be tableted or other excipients can be added prior to tableting such as a glidant and or lubricant.
A tableting composition can be prepared conventionally by dry blending. For instance, the blended composition of the actives and excipients can be compacted into a slug or a sheet and then comminuted into compacted granules. The compacted granules can be compressed subsequently into a tablet.
As an alternative to dry granulation, a blended composition can be compressed directly into a compacted dosage form using direct compression techniques. Direct compression produces a more uniform tablet without granules. Excipients that are particularly well suited to direct compression tableting include microcrystalline cellulose, spray dried lactose, dicalcium phosphate dihydrate and colloidal silica. The proper use of these and other excipients in direct compression tableting is known to those in the art with experience and skill in particular formulation challenges of direct compression tableting.
A capsule filling of the present invention can comprise any of the aforementioned blends and granulates that were described with reference to tableting, only they are not subjected to a final tableting step.
Yet more particularly, a tablet can, for example, be formulated by blending and directly compressing the composition in a tablet machine.
A capsule can, for example, be prepared by filling half of a gelatin capsule with the above tablet composition and capping it with the other half of the gelatin capsule.
A simple parenteral solution for injection can, for example, be prepared by combining carvedilol Form VI, sterile propylene glycol, and sterile water and sealing the composition in a sterile vial under sterile conditions.
Capsules, tablets and lozenges and other unit dosage forms preferably contain a dosage level of about 1 mg to about 100 mg of carvedilol Form VI.
The following examples are given for the purpose of illustrating the present invention and shall not be construed as limiting the scope or spirit of the invention.
EXAMPLES
General
The powder X-ray diffraction patterns were obtained by methods known in the art using a SCINTAG powder X-ray diffractometer model X′TRA, variable goniometer, equipped with a solid-state detector. Copper radiation of λ=1.5418 Å was used. The scanning parameters included: measurement range: 2-40 degrees two-theta; continuous scan; rate: 3 degrees/minute.
The thermogravimetric curves were obtained by methods known in the art using a Mettler Toledo DSC821 e . The weight of the samples was about 3-5 mg. The temperature range was from about 30° C. to at least 250° C., at the rate of 10° C./minute.
The thermogravimetric curves were also obtained by methods known in the art using a Shimadzu DTG-50. The temperature range was from about 30° C. to at least 250° C., at the rate of 10° C./minute. Samples were purged with nitrogen gas at a flow rate of 20 ml/min.
The FTIR spectra were obtained by methods known in the art, such as diffuse reflectance, using a Perkin-Elmer, Spectrum One FTIR Spectrometer. The scanning parameters were as follows: range: 4000-400 cm −1 , 16 scans, resolution: 4.0 cm −1 .
Example 1
Carvedilol Form VI
Dry carvedilol (7 Kg) was added to ethyl acetate (70 L) and heated to about 70-77° C. under agitation. After complete dissolution, the solution was cooled to about 46-50° C. under agitation. The solution was then seeded with carvedilol Form II and stirred at a temperature of about 46-50° C. for about 30 minutes under high velocity agitation (at least 260 rpm). The resulting suspension was cooled to a temperature of about 10° C. over a period of 3 hours under high velocity agitation. The suspension was stirred for an addition 30 minutes and then filtered to obtain carvedilol Form VI.
Example 2
Carvedilol Form II
Three trays containing carvedilol Form VI (1 Kg per tray) were inserted into a vacuum oven, heated to about 55° C. under vacuum of 30 mm Hg and dried for about 16 hours. Immediately after drying, the polymorphic content of the dried sample was a mixture of Form VI and Form II. After storage at room temperature for about 4 weeks, a mixture of Form I, Form II and Form VI were found.
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This invention relates to a novel crystalline solid of carvedilol or a solvate thereof, to processes for its preparation, to compositions containing it and to its use in medicine. This invention further relates to a novel process for preparing a crystalline solid of carvedilol Form II.
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BACKGROUND OF THE INVENTION
It is known from European Application EP 0 785 605 A1 to provide ignition voltage for a spark plug in an internal combustion engine by use of a high voltage step-up transformer mounted directly above the spark plug. The high voltage transformer utilizes a magnetic core having a pencil-shape, and thus has become commonly known as a "pencil core".
FIGS. 1A, 1B, and 1C show an illustration of such a known prior art pencil core. As generally illustrated at 10 in the cross-sectional view of FIG. 1A, a plurality of thin magnetic metal laminations 11 of varying width, but having a substantially constant thickness and a same length are stacked so that a resulting substantially circular profile shown in FIG. 1B results.
In order to maintain the stack as a unified body, it is known to provide a plurality of rectangular embossments such as 12A, 12B, and 12C in each lamination 11 so that as shown in FIG. 1A or 1B, the embossment of the upper lamination fits into the inside of the embossment of the following lamination and so on until the last lamination at the bottom of the stack such as 13, where apertures 14A, B, C are provided in lieu of the embossments so that the next to the last lamination embossments fit within the apertures 14A, B, C, in the bottom lamination so that there is no projection beyond the bottom surface of the bottom lamination.
FIG. 1C shows a plan view clearly illustrating what the prior art pencil core looks like from the top viewing down upon the top most lamination. In FIG. 1C and also FIG. 1B it can be readily seen that the central two laminations of a total of twenty laminations 11, for example, have the same width, whereas laminations above and below the two central laminations have decreasing width.
It is known that such pencil core laminations, instead of rectangular embossments, can be held together such as by welding.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a method for high volume, cost effective manufacture of a pencil core generally of the type illustrated in FIGS. 1A, 1B, and 1C.
According to the present invention, a pencil core manufacturing die according to the present invention performs the following manufacturing steps in order to cost effectively manufacture pencil cores at high volume.
First, the magnetic steel raw material in the shape of a strip known as feed stock is fed into the progressive stamping die. At a pilot hole punch station, one or more pilot holes are punched into the strip for later use in registration. Thereafter, at a first pilot registration station a pilot member is registered with the one or more pilot holes. Thereafter, in a first scrap removal station two substantially parallel scrap regions are blanked out from the feed stock strip using cam activated engagement punches. These two regions are at a given spacing from one another. Thereafter, in a second pilot registration station a pilot registration member is registered with the one or more pilot holes and thereafter a second scrap region blanking station blanks out two more spaced apart and parallel scrap regions from the strip at a different spacing than the first scrap region blanking station using cam activated engagement punch. Thereafter, the pattern repeats with pilot registration stations and scrap region blanking stations with cam activated engagement punches for as many laminations are required to reach the middle of the pencil core. For the manufacture of the two central laminations of equal width, no scrap region blanking stations are required. Moreover, for the second half of the pencil core the same pilot registration and scrap region blanking stations are employed since the pattern of changing width repeats.
Preferably the spacing of the blanked out scrap regions and the subsequent scrap region blanking stations have a constant width but increasing spacing from one another relative to a central reference line.
At some point preferably near the end of the row of scrap region blanking and pilot registration stations a piercing station is provided for piercing through holes in only the last lamination of the core.
After the last scrap region blanking station, an embossing station is provided for creating a embossment or projection which is preferably round (but could be rectangular) in each of the laminations except for the last lamination of the pencil core for interlocking the laminations. The last lamination is not embossed since that lamination has through holes from the piercing station. Therefore, the next to the last lamination projections will fit into the holes in the last lamination.
Finally, a blanking and stacking station is provided in which the laminations are cut free from the strip and pushed against one another so that the projections interlock. A choke aperture in the blanking and stacking station holds the pencil cores by the central two widest laminations. The completed stacked pencil cores then are pushed downwardly through the choking bushing until they are clear of the choking bushing and are thus delivered to an outlet of the die for completed pencil cores.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A is a side cross-sectional view of a prior art pencil core taken along line 1A--1A of FIG. 1C;
FIG. 1B is a cross-sectional view taken along the line 1B--1B of FIG. 1C of the prior art pencil core;
FIG. 1C is a top view of the prior art pencil core;
FIGS. 2A and 2B are a top view and a cross-section side view of a pencil core modified in accordance with the present invention for use in the method of the invention for manufacturing a pencil core;
FIG. 3 is a side view taken along section line III--III of FIG. 4 showing a die used in the manufacture of pencil cores according to the present invention;
FIG. 4 is a top view taken along section line IV--IV of FIG. 3;
FIG. 5 is a view taken along section line V--V of FIG. 4;
FIG. 6 is a sectional view taken along line VI--VI of FIG. 4;
FIG. 7 is a sectional view taken along line VII--VII of FIG. 4;
FIG. 8 is an end view of the pencil core showing correlation of layer level and the stations enumerated in FIG. 4 for each of understanding; and
FIG. 9 is a top view of the strip as blanked at three of the scrap area blanking stations showing changing spacing of blanked scrap regions.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The pencil core of the prior art is modified according to the present invention for use in the manufacturing method according to the present invention. As shown in the top view in FIGS. 2A and 2B, the uppermost lamination 15 of the pencil core 16, has three circular embossments or projections 18A, 18B and 18E rather than a rectangular projection of the prior art. Such circular projections are shown interlocking with one another in FIG. 2B. The circular projections are provided in the laminations 17 except for the last lamination 19 where a corresponding hole 19A, 19B, 19C is provided. The circular projection has substantial advantages for this pencil core compared to the prior art rectangular embossments based on ease of production since the punches which make these circular projections are easier to maintain and thus simpler to design in combination with their corresponding die bushings.
Additionally as shown in FIG. 2A and in FIG. 2B, transport holes 20A and 20B may be provided in the uppermost lamination 15 and all of the remaining laminations 17 and the bottom lamination 19 which are all in alignment with one another. Advantageously, when the pencil core exits from the die according to the present invention, the pencil cores can be grouped together by a wire passing through these transport holes from pencil core to pencil core. This simplifies transport to an annealing oven, for example.
In the partial cross-sectional view of FIG. 3, the die according to the present invention utilized to manufacture the pencil cores is generally illustrated at 21. Die 21 is formed of punch holder 22 and die shoe 23. The magnetic material strip 24 shown moving from right to left by arrow 25 is positioned between the punch holder 22 and die shoe 23.
As shown in FIG. 4 a plurality of substantially identical die guide post bushings 26 lying at both sides of the strip 24 are provided in the die shoe 23. These die guide post bushings 26 receive corresponding mating guide pins in known prior art fashion projecting from the punch holder 22 but not otherwise shown in FIGS. 3 and 4 for clarity. Four mounting bolt holes 27 are provided at corners of the die shoe 23. Corresponding recesses 28 partially surround the mounting holes 27.
Stop blocks 29 stopping downward movement of the punch holder 22 are provided adjacent the recesses 28 at the four corners of the die shoe 23.
The strip 24 is aligned along a die block area 100.
At an end clamp 30 is provided at the outlet end of the die and a corresponding scrap cutter 31 is provided above the end clamp 30 to trim off remaining scrap portions of the strip 24 at the outlet of the die.
A plurality of stations designated 1 through 22 are illustrated in FIG. 4. The stations will be described in greater detail hereafter. To distinguish these station numbers 1 through 22 from reference numerals in the drawings, circles have been provided around the station numbers.
The construction of station 1 can be most readily seen in FIG. 3. This station 1 is a pilot perforator station which provides perforation or pilot holes 32 aligned to one side of a reference center line 33 and holes 34 lying on the opposite side of reference center line 33 (see FIG. 4). These holes are engaged by pilot members at the various pilot stations described hereafter. These pilot holes 32 and 34 are provided by corresponding punches 35A, B received in corresponding die bushings 36A, B. A slug scrap escapement 37A, B is provided beneath each of the two die bushings 36A, B.
Station 2 is exemplary of the plurality of pilot stations 2, 4, 6, 8, 10, 12, 14, 16, 18 and 20. The pilot stations each have a pair of pilot members 72A, B received in corresponding guide bushings 38A, B of the stripper. An air clearance hole 39A, B is located beneath each guide bushing 38A, B in the die block and die shoe. A pilot spring 40A, B is provided for biasing each of the pilot members 72A, B. These pilot members ensure registration of the strip as it proceeds along the die in the die block area 100.
If desired, additional pilot members 72A, B with associated pilot springs 40A, B guide bushings 38A, B, and air clearance holes 39A, B can be provided at the scrap region blanking stations as shown by the pilot holes 32 and 34 lying at both sides of the blank scrap regions at stations 3, 5, 7, 9, 11, 13, 15, 17 and 19.
The precise location of pilot stations and corresponding pilot members can be varied and the total number of such pilot stations can also be varied.
Preferably, however, a pilot station precedes each scrap region blanking station.
Station 3 is exemplary of a scrap region blanking station, and is substantially identical to additional scrap region blanking stations 5, 7, 9, 11, 13, 15, 17 and 19 except for an increasing spacing of scrap regions as shown in FIG. 9 hereafter.
In each scrap region blanking station, a pair of trim punches of rectangular configuration corresponding in shape and area to the corresponding space blanking region 42A and 42B shown in FIG. 4 but more clearly shown in FIG. 9. The trim punches 41A, B are received in respective rectangular die sections 43A, B which lie above respective scrap slug escapements 44A, B which can either be a corresponding escapement below each rectangular die section or a unified escapement for receiving scrap from both rectangular die sections.
Preferably the trim punches 41A, B in each of the scrap region blanking stations 3, 5, 7, 9, 11, 13, 15, 17 and 19 a re cam activated for selective activation in row order along the strip or in arbitrary sequences as described hereafter.
Preferably between scrap region blanking stations 17 and 19 a piercing station may be provided at the pilot member station 18 which is slide cam activated so as to provide the holes 19A, 19B, 19C only in the last lamination 19 shown in FIG. 2B. This piercing station, which provides the hole for allowing stack separation, has a punch 45 passing through a guide bushing 46 into a die bushing 47. The die bushing 47 is arranged above a s crap or slug escapement 48.
Between scrap region blanking station 19 and pilot station 20 an embossing station is provided for creating the circular embossments 18A, 18B and 18C shown in FIG. 2A. This embossing station has an embossing punch 49 received in a guide bushing 50 positioned above a die bushing 51. A shedder pin 52 biased by a spring 53 is provided. Thus, the shedder pin 52 is biased against the bottom surface of the lamination where the embossing punch 49 is creating the circular embossment 18A, 18B and 18C.
The through holes 20A and 20B shown in FIG. 2A can be added to all of the laminations at a station not shown in FIG. 3 or 4.
Finally, the station 21 is a blanking and stacking station which performs both of the blanking and stacking functions at a single station. A punch 54 is received within a die section 55 so as to blank each lamination free from the strip 24. A rectangular choking section 56 inserted into the collar section 56 having an inner dimension adapted for a tight fit with the widest two central laminations 8 and 9 as shown in FIG. 8 is provided.
FIG. 5 shows a cross-sectional end view of station 3 which is the first scrap region blanking station. Identical punches 41A, B are substantially simultaneously activated by a slide 57 having substantially identical notches 57A and 57B with cammed entry surfaces. The slide 57 is driven by an air cylinder 58 via an intermediate coupling member 59 activated via a PLC or computer. The stripper plate 60 is also shown with identical stripper guides 61 A, B. The rectangular die sections 43A, B are also shown together with corresponding scrap slug escapements 44A and 44B. The strip 24 is positioned in a strip channel 62 of the stripper plate 60.
FIG. 6 is a cross-sectional view taken along line VI--VI and shows the piercing station for the last lamination of each pencil core. This piercing station provides all three of t he apertures 19A, 19B shown in FIG. 2B. Thus for the last lamination, the punch 45 is actuated three times by a slide 63 and a cut out 63A. The slide is driven by a coupling member 64 driven by an air cylinder 65 activated via a PLC or computer. The punch 45 is received in the stripper guide bushing 46 and blanking occurs with the die bushing 47 position ed above the slug clearance 48.
FIG. 7 shows the section view along line VII--VII for the blanking and stacking station. As shown in FIG. 7, the blanking and stacking station punch 54 passes through stripper plate 60 to strike the strip 24 in the stripper channel 62. As the laminations are blanked free from the strip they are forced together such that the embossments previously described hold the individual laminations together to form unitary pencil cores 16. The last laminae 19 in each pencil core 16 does not have an embossment, but rather a hole, and therefore it is not mechanically held to the adjacent pencil core 16 lying below.
The assembled pencil cores 16 pass down through the die section 55 into the pinch or choke section 56. Finally they are released into an aperture 68 in a bolster plate 67, and they freely slide down such as to a curved chute 69 or onto a conveyor.
FIG. 8 shows correspondence in a preferred embodiment between the pencil core layer level 1 through 20 for the twenty different laminations at the left side and at the right side station numbers are provided so that it can be seen where the corresponding scrap region blanking stations 3 through 19 correspond and wherein the station 21 (which is the blanking station), which cuts free the central laminations 10 and 11. It may be appreciated that after formation of layers 1 through 10, that layers 11 through 20 which are subsequently deposited utilizing the same scrap region blanking stations. That is to say, the layers 1 through 9 requiring the different spacings for the scrap regions utilize those same scrap region blanking stations for formation of layers 12 through 20 of varying width. As previously indicated the central two laminations 10 and 11 having the same width, which is the widest width, do not require for their formation scrap region blanking since in the case of these central laminations 10 and 11 (designated with reference numerals 9 and 8), they are simply cut free from the strip at the final blanking and stacking station 21.
FIG. 9 shows more clearly the progressively wider spacing of the scrap regions for consecutive stations 3, 5 and 7, for example. It can be seen from this drawing that the width and length of the scrap regions 42A; 42B; 70A; 70B; and 71A, 71B are constant, but that the spacing D1 is smaller than spacing D2, which in turn is smaller than spacing D3. Thus when the respective laminae represented by these scrap regions are blanked out at the blanking and stacking station 21, the different widths for respective laminaes 1, 2 and 3 shown in FIG. 8 result. Of course, alternatively the station 3, 5 and 7 are utilized in the formation of the laminations 20, 19, and 18 in the second half of the pencil core, as shown in FIG. 8.
It should be understood that although twenty layer levels were shown for the pencil core in FIG. 8, that differing numbers of layer levels may be employed. It should also be understood that the slide cam actuating of the various scrap region blanking stations can be sequenced in varying ways.
Also, it should be understood that this die can have multiple rows.
Although various minor modifications might be suggested by those skilled in the art, it should be understood that I wish to embody within the scope of the patent warranted hereon all such modifications as reasonably and properly come with the scope of my contribution to the art.
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In a method of making a pencil core having a plurality of substantially flat laminations wherein at least one lamination at the center of the core is wider than the other laminations, a flat strip of core steel is fed into a progressive die, and a plurality of scrap region blanking stations is provided each of which blank out two spaced parallel regions from the strip, but with each of the scrap region blanking stations blanking out the regions at a different spacing. At an embossing station, at least one embossment is provided in at least each of the laminations preceding the last lamination. After all of the scrap region blanking stations, a blanking and stacking station first blanks laminations free from the strip at and corresponding to the parallel scrap regions of different spacing, and as each lamination is blanked free from the strip, that lamination is stacked onto the previously blanked laminations to form completed cores, the completed cores being held in a choking section of the blanking and stacking station. This die can also have multiple rows.
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GOVERNMENT SUPPORT
This invention was made with government support under contract No. CA-29995 by the U.S. National Institutes of Health. The government has certain rights in the invention.
This is a continuation of application Ser. No. 07/646,291, filed Jan. 25, 1991, now abandoned.
BACKGROUND OF THE INVENTION
The adhesion of mammalian cells to the extracellular matrix is of fundamental importance in regulating growth, adhesion, motility and the development of the proper cellular phenotype. This has implications for normal cell growth and development, wound healing, chronic inflammatory diseases, diabetes, and tumor metastasis. Evidence accumulated over the last several years suggests that the molecular basis for the adhesion of both normal and transformed or malignant cells is complex and probably involves several distinct cell surface molecules. Extracellular matrices consist of three types of macromolecules: collagenous glycoproteins, proteoglycans and noncollagenous glycoproteins.
One noncollagenous adhesive glycoprotein of interest is laminin. Laminin likely is one of a multigene family of related molecules [Ohno et al., Conn. Tiss. Res., 15, 199-207 (1986); Hunter et al., Nature, 338, 229-234 (1989); Sanes et al., J. Cell Biol., 111, 1685-1699 (1990)]. Laminin is a high molecular weight (approximately 850,000; from the mouse Engelbreth-Holm-Swarm tumor) extracellular matrix glycoprotein found almost exclusively in basement membranes. [Timpl et al., J. Biol. Chem., 254, 9933-9937 (1979)]. Basement membranes are an ubiquitous, specialized type of extracellular matrix separating organ parenchymal cells from interstitial collagenous stroma. Interaction of cells with this matrix is an important aspect of both normal and neoplastic cellular processes. Normal cells appear to require an extracellular matrix for survival, proliferation, and differentiation, while migratory cells, both normal and neoplastic, must traverse the basement membrane in moving from one tissue to another.
Laminin isolated from the Engelbreth-Holm-Swarm murine tumor consists of three different polypeptide chains: B1 with 215,000 MW, B2 with 205,000 MW and A with 400,000 MW [Timpl and Dziadek, Intern. Rev. Exp. Path., 29, 1-112 (1986)]. When examined at the electron microscopic level with the technique of rotary shadowing, it appears as an asymmetric cross, with three short arms 37 nm long (the lateral short arms having two globular domains and the upper short arm having three globular domains [Sasaki et al., J. Biol. Chem., 263, 16536-16544 (1988)]}, and one long arm 77 nm long, exhibiting a large terminal globular domain [Engel et al., J. Mol. Biol., 150, 97-120 (1981)]. The three chains are associated via disulfide and other chemical bonds. Structural data shows that laminin is a very complex and multidomain protein with unique functions present in specific domains.
Laminin is a major component of basement membranes and is involved in many functions. Laminin has the ability to bind to other basement membrane macromolecules and therefore contributes to the structural and perhaps functional characteristics of basement membranes.
Laminin promotes the adhesion and spreading of a multitude of cells and binds a variety of proteoglycans [Timpl and Dziadek, supra (1986)]. Studies utilizing enzymatic digests of laminin or monoclonal antibodies raised against laminin have defined some of the biologically active regions of the 400 kD A chain of laminin. The amino terminal globular domain at the top of the molecule is involved in laminin-laminin self assembly [Yurchenco et al., J. Biol. Chem., 260, 7636-7644 (1985)] and the adhesion of hepatocytes [Timpl et al., J. Biol. Chem., 255, 8922-8927 (1983)]. In addition, its large carboxy-terminal globular domain binds heparin [Ott et al., Eur. J. Biochem., 123, 63-72 (1982); Skubitz et al., J. Biol. Chem., 263, 4861-4868 (1988)], while neurite cell outgrowth and cell adhesion is localized to the region directly above this globule [Edgar et al., EMBO J., 3, 1463-1468 (1984); Engvall et al., J. Cell Biol., 103, 2457-2465 (1986); Goodman et al., J. Cell Biol., 105, 589-598 (1987)].
Another important feature of laminin is its ability to associate with cell surface molecular receptors and consequently modify cellular phenotype in various ways. Receptors for laminin ranging in molecular size from 55 to 180 kD have been isolated from a variety of normal and malignant cell lines [Rao et al., Biochem. Biophys. Res. Commun., 111, 804-808 (1983); Lesot et al., EMBO J., 2, 861-865 (1983); Malinoff and Wicha, J. Cell Biol., 96, 1475-1479 (1983); Terranova et al., Proc. Natl. Acad. Sci. U.S.A., 80, 444-448 (1983); Barsky et al., Breast Cancer Res. Treat., 4, 181-188 (1984); von der Mark and Kuhl, Biochim. Biophys. Acta., 823, 147-160 (1985); Wewer et al., Proc. Natl. Acad. Sci. U.S.A., 83, 7137-7141 (1986); Hinek et al., J. Cell Biol., 105, 138a (1987); Yoon et al., J. Immunol., 138, 259-265 (1987); Smalheiser and Schwartz, Proc. Natl. Acad. Sci. U.S.A., 84, 6457-6461 (1987); Yannariello-Brown et al., J. Cell Biol., 106, 1773-1786 (1988); Mercurio and Shaw, J. Cell Biol., 107, 1873-1880 (1988); Kleinman et al., Proc. Natl. Acad. Sci. U.S.A., 85, 1282-1286 (1988); Hall et al., J. Cell Biol., 107, 687-697 (1988); Clegg et al., J. Cell Biol., 107, 699-705 (1988)]. In the case of human glioblastoma cells [Gehlsen et al., Science, 241, 1228-1229 (1988)], several chicken cell types [Horwitz et al., J. Cell Biol., 101, 2134-2144 (1985)], platelets [Sonnenberg et al., Nature, 336, 487-489 (1988)], and neuronal cell line PC12 [Tomaselli et al., J. Cell Biol., 105, 2347-2358 (1987); and J. Cell Biol., 107, 1241-1252 (1988)], the laminin receptor was determined to be an integrin. To date, however, the exact sequence of amino acid residues of laminin to which most of these receptors bind is unknown.
Recently, the amino acid sequences of the B1, B2, and A chains of laminin have been determined [Barlow et al., EMBO J., 3, 2355-2362 (1984); Sasaki et al., Proc. Natl. Acad. Sci. U.S.A., 84, 935-939 (1987); Sasaki et al., J. Biol. Chem., 263, 16536-16544 (1988); Sasaki and Yamada, J. Biol. Chem., 262, 17111-17117 (1987); Pikkarainen et al., J. Biol. Chem., 262, 10454-10462 (1987); Pikkarainen et al., J. Biol. Chem., 263, 6751-6758 (1988); Hartl et al., Eur. J. Biochem., 173, 629-635 (1988)], allowing peptides to be synthesized from domains of laminin with reported functional activity. Three peptides have been synthesized from the B1 chain of laminin which promote cell adhesion. The first peptide, cys-asp-pro-gly-tyr-iso-gly-ser-arg (SEQ ID NO: 6), located near the intersection of the cross, promotes the adhesion of a variety of cells [Graf et al., Cell, 48, 989-996 (1987a); Biochemistry, 26, 6896-6900 (1987b)] and is thought to bind a 67 kD protein laminin receptor [Graf et al., supra (1987b); Wewer et al., supra (1986)]. The second, peptide F-9 (arg-tyr-val-val-leu-pro-arg-pro-val-cys-phe-glu-lys-gly-met-asn-tyr-thr-val-arg) (SEQ. ID. NO: 7), also promotes the adhesion of a variety of cells and binds heparin (U.S. Pat. No. 4,870,160) Charonis et al. J. Cell Biol., 107, 1253-1260 (1988). A third peptide from the B1 chain of laminin, termed AC15 {arg-ile-gln-asn-leu-leu-lys-ile-thr-asn-leu-arg-ile-lys-phe-val-lys (SEQ. ID. NO: 8) [Kobuzi-Koliakos et al., J. Biol. Chem., 264, 17971-17978 (1989)]} also binds heparin, and is derived from the outer globule of a lateral short arm. AC15 promotes the adhesion of murine melanoma and bovine aortic endothelial cells [Koliakos et al., J. Cell Biol., 109, 200a (1989)].
Since the A chain was the last chain of laminin for which the entire amino acid sequence was determined, only a few peptides have been described with functional activity. Synthetic peptide PA 21 (residues #1115-1129; cys-gln-ala-gly-thr-phe-ala-leu-arg-gly-asp-asn-pro-gln-gly) (SEQ. ID. NO: 9), which contains the active sequence RGD, induces the attachment of human endothelial cells through an integrin receptor [Grant et al., Cell, 58, 933-943 (1989)]. Peptide PA22-2 (residues #2091-2108; ser-arg-ala-arg-lys-gln-ala-ala-ser-ile-lys-val-ala-val-ser-ala-asp-arg), (SEQ. ID. NO: 10), contains the active sequence ile-lys-val-ala-val (SEQ. ID. NO: 11) [Tashiro et al., J. Biol. Chem., 264, 16174-16182 (1989)] and has a number of biological functions such as promoting neuronal process extension [Tashiro et al., supra (1989); Sephel et al., Biochem. Biophys. Res. Commun., 162, 821-829 (1989)]. Recently the biological activity of this peptide has come into question.
The functions that have been described above make laminin an important component of many diverse and clinically important processes such as cell migration, cell adhesion, cell growth, cell differentiation, wound healing, angiogenesis in general, nerve regeneration, tumor cell invasion and metastasis [Liotta, Am. J. Path., 117, 339-348 (1984); McCarthy et al., Cancer Met. Rev., 4, 125-152 (1985)], diabetic microangiopathy, and vascular hypertrophy due to hypertension, atherosclerosis and coronary artery disease, and vessel wall healing after angioplasty. Laminin could also be used in various devices and materials used in humans. In order to better understand the pathophysiology of these processes at the molecular level, it is important to try to assign each of the biological activities that laminin exhibits to a specific subdomain or oligopeptide of laminin. If this can be achieved, potentially important pharmaceuticals based on small peptides or compounds that bind to the receptors producing specific functions of the native, intact molecule, can be synthesized.
Therefore, a need exists to isolate and characterize peptides which are responsible for the wide range of biological activities associated with laminin. Such lower molecular weight oligopeptides would be expected to be more readily obtainable and to exhibit a narrower profile of biological activity than laminin itself, thus increasing their potential usefulness as therapeutic or diagnostic agents.
BRIEF DESCRIPTION OF THE INVENTION
The present invention provides polypeptides which represent fragments of the amino terminal globular domain [domain VI as denoted by Sasaki et al., supra (1988)] of the A chain of laminin. These polypeptides are at least 5 amino acids in length and can be prepared by conventional solid phase peptide synthesis. The formulas of preferred peptides are: ##STR1## Polypeptide R17 formally represents isolated laminin residues 34-50 from the A chain of laminin; polypeptide R18 formally represents isolated laminin residues 42-63 from the A chain of laminin; polypeptide R19 formally represents isolated laminin residues 145-158; polypeptide R20 formally represents isolated laminin residues 204-217; and polypeptide R32 formally represents isolated laminin residues 226-245 from the deduced sequence of the EHS laminin A chain. The single letter amino acid codes for these polypeptides are KLVEHVPGRPVRHAQCR (SEQ. ID. NO: 1), RPVRHAQCRVCDGNSTNPRERH (SEQ. ID. NO: 2), RYKITPRRGPPTYR (SEQ. ID. NO: 3), ARYIRLRLQRIRTL (SEQ. ID. NO: 4), and HRDLRDLDPIVTRRYYYSIK (SEQ. ID. NO: 1), respectively.
These synthetic polypeptides were assayed for bioactivity and found to be potent promoters of cell adhesion to synthetic substrates. In particular, peptide R18 promoted the adhesion of a variety of cells including: (a) melanoma cells, (b) fibrosarcoma cells, (c) human colon cells, (d) human renal cells, and (e) human keratinocytes. Therefore, it is believed that these polypeptides, among many other things, may be useful to: (a) assist in nerve regeneration, (b) promote wound healing and implant acceptance, (c) promote cellular attachment and growth on culture substrata, and (d) inhibit the metastasis of malignant cells. Due to the difference in the spectra of biological activities exhibited by the polypeptides described herein, mixtures of these peptides are within the scope of the invention.
Furthermore, since it is expected that further digestion/hydrolysis of polypeptides from domain VI of the A chain of laminin in vitro or in vivo will yield fragments of substantially equivalent bioactivity, such lower molecular weight polypeptides are considered to be within the scope of the present invention. For example, while preferred domain VI polypeptides of the A chain of laminin described herein have sequences of at least 14 amino acids, it is to be understood that polypeptides having shorter sequences of amino acids and with functionally active sequences are within the scope of the invention. For example, polypeptides having sequences of fewer than 10 amino acids with functionally active sequences are within the scope of the invention. Further, it is believed that polypeptides having sequences of at least about 5 amino acids with functionally active sequences are within the scope of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagrammatic depiction of laminin, indicating the relative location of the A, B1 and B2 chains including globular regions located on each chain.
FIG. 2 is a diagrammatic depiction of the A chain of laminin, including domain VI. The location of certain synthetic peptides is shown.
FIG. 3 shows adhesion of HT-1080 human fibrosarcoma cells to laminin A chain peptides. FIG. 3 reports results in microtiter wells adsorbed with increasing concentrations of HPLC-purified peptides R17 (∘) R18 (□), or R19 (Δ), R20 ( ), R32 ( ), laminin ( ), or ovalbumin ( ) and radiolabeled HT-1080 human fibrosarcoma cells that were allowed to adhere for 2 hours after being released from flasks with EDTA/trypsin. Each value represents the mean of four separate determinations, and the SEM was less than 10% in each case.
FIG. 4 shows human HT-1080 fibrosarcoma cell spreading on a plastic surface coated with laminin.
FIG. 5 shows human HT-1080 fibrosarcoma cell spreading on a plastic surface coated with synthetic peptide R17 derived from the A chain of laminin.
FIG. 6 shows human HT-1080 fibrosarcoma cell spreading on a plastic surface coated with synthetic peptide R18 derived from the A chain of laminin.
FIG. 7 shows human HT-1080 fibrosarcoma cell spreading on a plastic surface coated with synthetic peptide R19 derived from the A chain of laminin.
FIG. 8 shows human HT-1080 fibrosarcoma cell spreading on a plastic surface coated with synthetic peptide R20 derived from the A chain of laminin.
FIG. 9 shows human HT-1080 fibrosarcoma cell spreading on a plastic surface coated with synthetic peptide R32 derived from the A chain of laminin.
FIG. 10 shows human HT-1080 fibrosarcoma cell spreading on a plastic surface coated with ovalbumin (negative control protein).
FIG. 11 shows inhibition of laminin-mediated HT-1080 human fibrosarcoma cell adhesion by laminin A chain peptide R11. FIG. 11 reports results in microtiter wells absorbed with 0.7 μg of laminin to which cells pre-incubated for 30 minutes in increasing concentrations of HPLC-purified peptide R17 (∘) were added and incubated for 30 minutes. Each value represents the mean of four separate determinations and the SEM was less than 10% in each case.
DETAILED DESCRIPTION OF THE INVENTION
Structure of Laminin and the A Chain
Referring to FIG. 1, when examined by the electron microscope utilizing rotary shadowing techniques, the structure of laminin derived from the mouse EHS tumor appears as an asymmetric cross. The three short arms each have multiple globular domains and are 37 nm in length. The long arm exhibits one large terminal globular domain and is 77 nm in length [Engel et al., supra (1981)]. Laminin likely is one of a multigene family of related molecules [(Ohno et al., supra (1986); Hunter et al., supra (1989); Sanes et al., supra (1990)]. As seen in FIG. 1, the three chains are associated via disulfide bonds and other chemical bonds. The amino acid sequences of all three polypeptide chains of laminin have now been deduced by sequencing isolated clones having specific laminin genes [Sasaki et al., supra (1988); Sasaki and Yamada, supra (1987); Sasaki et al., J. Biol. Chem., supra (1988)]. Taken together, the three chains are composed of a total of 6,456 amino acids. A diagrammatic model of the A chain is shown in FIG. 2.
In an earlier study, hepatocytes were shown to adhere to a proteolytic resistant fragment of laminin comprised of domain VI (Timpl et al., supra (1983)]. However, the exact amino acid sequence responsible for promoting hepatocyte adhesion is not known and therefore no related oligopeptide has been identified.
Domain VI of laminin does not seem to bind glycosaminoglycans or proteoglycans, as evident by studies which localized heparin binding activity to other sites of laminin (Ott et al., supra (1982); Skubitz et al., supra (1988)]. Therefore, it is likely that cell surface receptors for domain VI of laminin, as well as for these synthetic peptides, are not proteoglycans or glycosaminoglycans. In fact, 3 H-heparin does not adhere to peptides R17, R18, R19, R20, or R32 in solid-phase binding assays. Perhaps integrins or other cell surface proteins serve as receptors for these peptides. A variety of integrins that bind laminin have been isolated from cells, including α 1 β 1 , α 2 β 1 , α 3 β 1 , α 6 β 1 , and α v β 3 , [Kirchhofer et al., J. Biol. Chem., 265, 615-618 (1990); Kramer et al., J. Cell Biol., 111, 1233-1243 (1990); Gehlsen et al., J. Biol. Chem., 264, 19034-19038 (1989)]. A few of these integrins have been shown to bind to specific regions of laminin. For example, the α 6 β 1 integrin appears to bind to the lower part of the long arm laminin [Sonnenberg et al., J. Cell Biol., 110, 2145-2155 (1990)] whereas β 1 and β 3 integrin subunits [Sonnenberg et al., supra (1990)] and the α 1 β 1 integrin from human JAR choriocarcinoma cells bind near the cross region of laminin [Hall et al., J. Cell Biol., 110, 2175-2184 (1990)]. The α 3 β 1 integrin from human MG-63 osteosarcoma cells has been reported to bind near the carboxy terminus of the B 1 chain of laminin [Gehlsen et al., supra (1989)]. However, the exact amino acid sequence of laminin to which any of these integrin subunits binds is not known and therefore no related oligopeptide has been identified.
Domain VI of laminin is also important for the self-assembly of laminin into aggregates. Laminin molecules polymerize into large complexes using the globular domains at the ends of the arms [Yurchenco et al., supra (1985)]. The two-step process is temperature-dependent and divalent cation-dependent [Yurchenco et al., supra (1985)]. In particular, the short arms of laminin, including domain VI, are crucial for self-assembly [Schittny and Yurchenco, J. Cell Biol., 110, 825-832 (1990)] and require calcium for self-assembly [Brunch et al., Eur. J. Biochem., 185, 271-279 (1989)]. Laminin self-assembly may be important in maintaining the structure of the basement membrane; perhaps by forming large aggregates, the pore size of a basement membrane can be reduced in order to restrict macromolecular permeation. Furthermore, this process may be important for basement membrane assembly during development and organogenesis [Ekblom, J. Cell Biol., 91, 1-10 (1981)].
According to the present invention, we have investigated domain VI of the A chain of laminin and synthesized a number of peptide fragments with cell attachment promoting activity. We synthesized 5 peptides, each of .sup.˜ 17 amino acid residues in length, from the published amino acid sequence of the amino terminal globular domain of the A chain of laminin [Sasaki et al., supra (1988)]. The polypeptides synthesized and their properties are set forth in Tables I and II, respectively. Peptides R17 and R18 are preferred embodiments of the present invention. Peptides R19, R20, and R32 also have biological activity.
TABLE I__________________________________________________________________________Peptides from the Amino Terminus of Laminin A Chain Sequence Net HydropathyPeptide Sequence* Numbers* Charge+ Index §__________________________________________________________________________R17 KLVEHVPGR 34-50 +5 -7.8 PVRHAQCR (SEQ ID NO:1)R18 RPVRHAQCRV 42-63 +5 -31.0 CDGNSTNPRERH (SEQ ID NO:2)R19 RYKITPRRGPPTYR (SEQ ID NO:3) 145-158 +5 -20.6R20 ARYIRLRLQRIRTL (SEQ ID NO:4) 204-217 +5 -7.4R32 HRDLRDLDPIVT 226-245 +3 -17.0 RRYYYSIK (SEQ ID NO:5)__________________________________________________________________________ *Based on Sasaki et al. 1988. [G = Glycine; A = Alanine' V = Valine; L = Leucine; I = Isoleucine; F = Phenylalanine; Y = Tyrosine; W = Tryptophan; M = Methionine; C = Cysteine; S = Serine; T = Threonine; H = Histidine; K = Lysine; R = Arginine; D = Aspartate; E = Glutamate; N = Asparagine; Q = Glutamine; P = Proline. +Calculated by assuming a +1 net charge for lysine (K) and arginine (R) residues and a -1 net charge for glutamic acid (E) and aspartic acid (D) at neutral pH. Histidine is assumed to be uncharged at this pH. §Calculated by the method of Kyte and Doolittle (1982). According to this method, more hydrophobic peptides correspond to the more positive numerical values. We constructed hydropathy plots for the entire A chain of laminin using a Sun Computer and an IntelliGenetics (Mountain View, CA program with a span setting of 6-7 amino acids.
Synthesis of the Polypeptides
The peptides listed in Table I (designated R-series), were derived from the amino terminal globular domain VI (residues #1-251; M r =26,695) of the A chain of EHS laminin. They were synthesized, then HPLC-purified as previously described by Charonis et al., J. Cell Biol., 107, 1253-1260 (1988). Purity was checked by HPLC and amino acid analysis. Specifically, the polypeptides of the invention were synthesized using the Merrifield solid phase method. This is the method most commonly used for peptide synthesis, and it is extensively described by J. M. Stewart and J. D. Young in Solid Phase Peptide Synthesis, Pierce Chemical Company, pub., Rockford, Ill. (2d ed., 1984), the disclosure of which is incorporated by reference herein.
The Merrifield system of peptide synthesis uses a 1% crosslinked polystyrene resin functionalized with benzyl chloride groups. The halogens, when reacted with the salt of a protected amino acid will form an ester, linking it covalently to the resin. The benzyloxy-carbonyl (BOC) group is used to protect the free amino group of the amino acid. This protecting group is removed with 25% trifluoroacetic acid (TFA) in dichloromethane (DCM). The newly exposed amino group is converted to the free base by 10% triethylamine (TEA) in DCM. The next BOC-protected amino acid is then coupled to the free amino of the previous amino acid by the use of dicyclohexylcarbodiimide (DCC). Side chain functional groups of the amino acids are protected during synthesis by TFA stable benzyl derivatives. All of these repetitive reactions can be automated, and the peptides of the present invention were synthesized by hand or at the University of Minnesota Microchemical facility by the use of a Beckman System 990 Peptide synthesizer.
Following synthesis of a blocked polypeptide on the resin, the polypeptide resin is treated with anhydrous hydrofluoric acid (HF) to cleave the benzyl ester linkage to the resin and thus to release the free polypeptide. The benzyl-derived side chain protecting groups are also removed by the HF treatment. The polypeptide is then extracted from the resin, using 1.0M acetic acid, followed by lyophilization of the extract. Lyophilized crude polypeptides are purified by preparative high performance liquid chromatography (HPLC) by reverse phase technique on a C-18 column. A typical elution gradient is 0% to 60% acetonitrile with 0.1% TFA in H 2 O. Absorbance of the eluant is monitored at 220 nm, and fractions are collected and lyophilized.
Characterization of the purified polypeptide is by amino acid analysis. The polypeptides are first hydrolyzed anaerobically for 24 hours at 110° C. in 6M HCl (constant boiling) or in 4N methanesulfonic acid, when cysteine or tryptophan are present. The hydrolyzed amino acids are separated by ion exchange chromatography using a Beckman System 6300 amino acid analyzer, using citrate buffers supplied by Beckman. Quantitation is by absorbance at 440 and 570 nm, and comparison with standard curves. The polypeptides may be further characterized by amino acid sequence determination. This approach is especially useful for longer polypeptides, where amino acid composition data are inherently less informative. Sequence determination is carried out by sequential Edman degradation from the amino terminus, automated on a Model 470A gas-phase sequenator (Applied Biosystems, Inc.), by the methodology of R. M. Hewick et al., J. Biol. Chem., 256, 7990 (1981).
Protein Isolation
Laminin was isolated from the EHS tumor as described by Palm and Furcht, J. Cell Biol., 96, 1218-1226 (1983) with minor modifications. Specifically, tumor tissue was homogenized in 3.4M NaCl, 0.01M phosphate buffer, pH 7.4, with 50 μg/ml of the protease inhibitors PMSF (Sigma Chemical Co., St. Louis, Mo.) and p-hydroxymercuribenzoate (Sigma Chemical Co.), washed twice with the same buffer, then extracted overnight with 0.5M NaCl, 0.01M phosphate, pH 7.4, and 50 μg/ml of the protease inhibitors. The salt concentration was raised to 1.7M followed by stirring overnight at 4° C., then spun at 15,000 rpm for 15 minutes. Laminin was precipitated from the supernatant overnight at 4° C. with 30% saturation ammonium sulfate. The precipitate was resuspended in 0.5M NaCl, 0.01M phosphate, pH 7.4, and dialyzed against the same buffer. Aggregates were removed by ultracentrifugation at 40,000 g for 1 hour at 4° C. Laminin was isolated from the supernatant by gel filtration chromatography on Sephacryl S-300 (Pharmacia Fine Chemicals, Piscataway, N.J.) (2.6×100 cm column) in the 0.5M NaCl buffer, where it eluted just after the void volume. The laminin solution was concentrated by evaporation while in a dialysis bag, dialyzed against PBS and stored at -70° C. The purity of laminin was verified by SDS-PAGE and ELISA. BSA (grade V, fatty acid free) was purchased from Sigma Chemical Co.
The invention will be further described by reference to the following detailed examples.
EXAMPLE 1
Cell Adhesion Assays
Cells
The human fibrosarcoma HT-1080 cell line was obtained from the ATCC. The murine melanoma K-1735-C10 (low metastatic) and K-1735-M4 (high metastatic) cell lines, murine UV-2237-MM fibrosarcoma cell line, human renal carcinoma SN12 PM-6 (high metastatic) cell line, and human colon carcinoma KM12 C (low metastatic) and KM12 SM (high metastatic) cell lines were originally provided by Dr. I. J. Fidler (M.D., Anderson Hospital, University of Texas Health Sciences Center, Houston, Tex.). The MM fibrosarcoma cell line was maintained in DME (GIBCO Laboratories, Grand Island, N.Y.) containing 10% FBS, the murine melanomas were maintained in DMEM containing 10% calf serum, the human fibrosarcoma cells were maintained in EMEM containing 10% heat inactivated FBS, and the human renal and colon carcinoma cells were grown in EMEM containing 10% FBS, vitamins, and 1 mM sodium pyruvate. Cells were passaged for 4 to 5 weeks and then replaced from frozen stocks of early passage cells to minimize phenotypic drift. Cells were maintained at 37° C. in a humidified incubator containing 5% CO 2 .
Assay Procedure and Results
The direct adhesion of cells to protein or peptide coated surfaces was performed as described in Skubitz et al., Exp. Cell Res., 173, 349-360 (1987) and Charonis et al., supra (1988). Briefly, radiolabeled cells were added to 96-well microtiter plates coated with various concentrations of synthetic peptides, laminin, or BSA (0.02 μg/well-50 μg/well from 50 μl solutions) for various lengths of time. After the incubation period, loosely or nonadherent cells were removed by washing the wells three times. Adherent cells were solubilized and quantitated in a scintillation counter. More specifically, cultures of cells which were 60-80% confluent were metabolically labeled for 24 hours with the addition of 3 μCi/ml of 3 H-td (tritiated thymidine). On the day of the assay, the cells were harvested by trypsinization, the trypsin was inhibited by the addition of serum, and the cells were washed free of this mixture and resuspended in DMEM buffered with HEPES at pH 7.2. The adhesion medium also contained 2 mg/ml BSA. The cells were adjusted to a concentration of 3-4×10 4 /ml, and 100 μl of this cell suspension was added to the wells. The assay mixture was then incubated at 37° C. for 120 minutes. At the end of the incubation, the wells were washed with warm DMEM/Hepes containing 2 mg/ml BSA, and the adherent population was solubilized with 0.5N NaOH contained 1% SDS. The solubilized cells were then quantitated using a liquid scintillation counter.
A representative example of the adhesion of cells to synthetic peptides is shown in FIG. 3. In this case, increasing concentrations of the five synthetic peptides were adsorbed to microtiter wells. Radiolabeled HT-1080 human fibrosarcoma cells were incubated in the wells for 120 minutes and the adhesion of cells was quantitated. Cells adhered to all 5 peptides in a concentration-dependent, saturable manner with maximal cell adhesion of approximately 40% of the total added cells occurring when wells were adsorbed with 3 μg of peptides R17, R18, R20, and R32. Similar patterns of concentration dependence and saturability were observed for peptide R19, however lower levels of cell adhesion were observed. In contrast, no cell adhesion was observed in wells adsorbed with ovalbumin even at concentrations as high as 5 μg/well.
Since peptide R18 promoted the highest levels of HT-1080 fibrosanoma cell adhesion, we decided to focus our studies on this peptide. Microtiter wells were adsorbed with peptide R18, laminin, or BSA and a variety of tumor cell lines were tested for the ability to adhere to the ligands. The six different tumor cell lines selected for this study were of murine or human origin and, in most cases, of either high or low metastatic capacity. As reported in Table II, peptide R18 was also capable of promoting the adhesion of all six cell lines.
TABLE II______________________________________Direct Cell Adhesion to Surfaces Coated withLaminin Synthetic Peptide R18 Cell Adhesion (%)* to Coated SurfacesCell Line Peptide R18 Laminin BSA______________________________________murine melanoma (M4) 15 50 3murine melanoma (C10) 37 80 1murine fibrosarcoma (MM) 44 43 1human colon carcinoma 56 36 2(K12SM)human colon carcinoma 35 25 3(K12C)human renal carcinoma 88 40 1(SN12 PM6)______________________________________ *Microtiter wells were coated with 5 μg of the peptide or proteins and radiolabeled cells were allowed to adhere for 2 hours. Cell adhesion is expressed as a percentage of the total number of cells added to the wells
EXAMPLE 2
Inhibition of Cell Adhesion to Surfaces Coated with Laminin
Inhibition of cell adhesion with synthetic peptides was performed using assays similar to those described by Skubitz et al., supra (1987). Briefly, radiolabeled cells at 5×10 4 /ml were incubated for 30 minutes with various concentrations of synthetic peptides (0.05 μg/ml-10 μg/ml) in DME/Hepes containing 2 mg/ml BSA. One hundred microliters of the cell suspension was then added to wells precoated with 0.7 μg of laminin. The cells were incubated for 30 minutes at 37° C., then the wells were washed and adherent cells were quantitated as previously described [Skubitz et al., supra (1987)]. Cell viability after a one hour incubation in the presence of the "inhibitors" was assessed by trypan blue dye exclusion. In all cases, the cells were >95% viable, and no toxicity of the peptides was observed at the indicated concentrations tested. Inhibition of cell adhesion by peptide R17 is reported in FIG. 11.
EXAMPLE 3
Cell Spreading Assay
Spreading of the adherent cells was evaluated by performing adhesion assays similar to those described above. Twenty-four well tissue culture plates (Becton Dickinson and Co., Lincoln Park, N.J.) were coated with 300 μl of laminin, synthetic peptides, or BSA at 100 μg/ml, then blocked with 2 mg/ml BSA in PBS. Three hundred microliters of a cell suspension at 5×10 4 cells/ml was added to each well, and after a 21/2 hour incubation, nonadherent cells were aspirated out of the wells. Adherent cells were fixed with 2% glutaraldehyde in PBS at 23° C. for one hour. The glutaraldehyde was then removed and the cells were stained by two different techniques. For photographic purposes, the cells were stained with Diff-Quik Solution I (American Scientific Products, McGaw Park, Ill.) for 10 minutes at 23° C. Solution I was removed, then Diff-Quik Solution II was added and the cells were stained for another 10 minutes at 23° C. Wells were washed with PBS, then representative cells were photographed with a Nikon DIAPHOT inverted phase microscope using Panatomic X Film ASA32 (Eastman Kodak, Rochester, N.Y.). Adherent cells to be quantitated for spreading were stained overnight at 23° C. with 500 μl of a solution containing 0.12% (w/v) Coomassie Brilliant Blue R (Sigma Chemical Co.), 5% (v/v) acetic acid, and 50% (v/v) ethanol. Wells were washed three times with 500 μl of PBS and cell spreading was then quantitated by measuring the average surface area occupied by a cell using an Opti-Max Image Analyzer. Thirty cells were measured per well; each experiment was done in quadruplicate and repeated three times. The quantitation of spreading for human HT-1080 fibrosarcoma cells is shown in Table III. Cells spread the best on peptides R17 and R18 and occupy an area of ˜30% of that seen for cells on laminin-coated surfaces. On surfaces coated with peptides R19, R20, and R32, less cell spreading was observed; cells occupied an area ˜20% of that seen on intact laminin. Cell spreading on ovalbumin (negative control) was less than 10% of that seen on laminin but the cells were barely adherent under these last conditions.
Human HT-1080 fibrosarcoma cell spreading on laminin synthetic peptides from the A chain is shown in FIGS. 4-10. The peptides of most interest to us are those which promoted the most cell spreading (i.e., peptides R17 and R18).
TABLE III______________________________________Quantitation of HT-1080 Human Fibrosarcoma CellSpreading on Surfaces Coated with Laminin A Chain Peptides Surface AreaLaminin A Occupied by CellsChain Peptide a Cell (μm.sup.2) Spread (%)______________________________________R17 235 ± 58 10R18 199 ± 59 5R19 129 ± 45 5R20 101 ± 34 0R32 122 ± 41 5Laminin 611 ± 79 95Ovalbumin 71 ± 41 0______________________________________
FIGS. 4 and 10 provided control comparisons for HT-1080 cell spreading evaluation.
EXAMPLE 4
Heparin Does Not Bind to Plastic Plates Coated with Peptides
The binding of 3 H-heparin to laminin A chain peptides was measured in a direct solid phase binding assay as described below, whereby various amounts of the peptides were adsorbed to plates and 3 H-heparin was added to each well. More specifically, the binding of 3 H-heparin (0.3 mCi/mg; Du Pont - New England Nuclear Research Products, Wilmington, Del.) to laminin, synthetic peptides, and bovine serum albumin (BSA) (fatty acid free, fraction V, ICN Immunobiologicals) was quantitated by a solid-phase RLBA in 96-well polystyrene Immulon 1 plates (Dynatech Laboratories, Inc., Alexandria, Va.) as described by Skubitz et al., supra (1988). Specifically, 50 microliters of the various proteins at various concentrations (0.2 μg/well-5.0 μg/well) in PBS containing 0.02% NaN 3 was added to each well and dried overnight at 29° C. The next day, 200 μl of 2 mg/ml BSA in PBS was added to each well, followed by a 2 hour incubation at 37° C. After removal of this buffer, 50 μl of 3 H-heparin (200,000 dpm) was added in RLBA buffer (20 mM Tris, pH 6.8 containing 50 mM NaCl and 2 mg/ml ovalbumin) and the wells were incubated at 37° C. for 2 hours. Unbound 3 H-heparin was removed by washing three times with wash buffer (RLBA buffer containing 0.1% CHAPS). Tritiated heparin was solubilized by incubation with 200 μl of 0.05N NaOH and 1% SDS for 30 minutes at 60° C. and quantitated in a Beckman LS-3801 scintillation counter. The results indicated that none of the peptides were capable of binding 3 H-heparin (not shown).
A number of practical applications for the polypeptides of the present invention can be envisioned. Such applications include the promotion of the healing of wounds and modulating the body's response to the placement of synthetic substrata within the body. Such synthetic substrata can include artificial vessels, intraocular contact lenses, hip replacement implants and the like, where modulating cell adhesion is an important factor in the acceptance of the synthetic implant by normal host tissue.
As described in U.S. Pat. No. 4,578,079, medical devices can be designed making use of these polypeptides to attract cells to the surface in vivo or even to promote the growing of a desired cell type on a particular surface prior to grafting. An example of such an approach is the induction of endothelial cell growth on a prosthetic device such as a blood vessel, heart valve or vascular graft, which is generally woven or knitted from nitrocellulose or polyester fiber, particularly Dacron™ (polyethylene terephthalate) fiber. Most types of cells are attracted to laminin and to the present polypeptides. The latter point indicates the potential usefulness of these defined polypeptides in coating a patch graft or the like for aiding wound closure and healing following an accident or surgery. The coating and implantation of synthetic polymers may also assist in the regeneration of nerves following crush trauma (e.g., spinal cord injuries) or after angioplasty.
In such cases, it may be advantageous to couple the peptide to another biological molecule, such as collagen, a glycosaminoglycan or a proteoglycan. It is also indicative of their value in coating or cross linking to surfaces of a prosthetic device which is intended to serve as a temporary or semipermanent entry into the body, e.g., into a blood vessel or into the peritoneal cavity, sometimes referred to as a percutaneous device. Such devices include controlled drug delivery reservoirs, catheters or infusion pumps.
Laminin can effectively promote the growth and differentiation of diverse cell types. Also, the polypeptides of the present invention can be used to promote cell adhesion of various cell types to naturally occurring or artificial substrata intended for use in vitro. For example, a culture surface such as the wells of a microtiter plate or the medium contacting surface of microporous fibers or beads, can be coated with the cell-attachment polypeptides.
As one example of commercial use of cell attachment surfaces, Cytodex 3® microcarriers, manufactured by Pharmacia, are dextran-based microspheres coated with denatured collagen, making it possible to grow the same number of adherent cells in a much smaller volume of medium than would be possible in dishes. The activity of these beads is generally dependent upon the use of coating protein in the growth medium and the present polypeptides are expected to provide an improved, chemically-defined coating for such purposes. Other surfaces or materials may be coated to enhance attachment, such as glass, agarose, synthetic resins or long-chain polysaccharides.
In the past, selected laminin domains have been studied for ability to decrease the metastatic potential of invasive cell lines [McCarthy et al., J. Natl. Cancer Inst., 80, 108-116 (1988)]. This effect is mediated via the saturation and therefore neutralization of cell surface receptors for laminin. In accordance with the present invention, the data presented herein suggest that receptors for the polypeptides derived from domain VI of the A chain of laminin should exist on cell surfaces of malignant cells. Consequently, these and related polypeptides could be used to block laminin receptors of metastatic cells and therefore reduce their metastatic potential or spreading.
The invention has been described with reference to various specific and preferred embodiments and techniques. However, it should be understood that many variations and modifications may be made while remaining within the spirit and scope of the invention.
__________________________________________________________________________SEQUENCE LISTING(1) GENERAL INFORMATION:(iii) NUMBER OF SEQUENCES: 11(2) INFORMATION FOR SEQ ID NO:1:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 17 amino acids(B) TYPE: amino acid(D) TOPOLOGY: linear(ii) MOLECULE TYPE: peptide(v) FRAGMENT TYPE: internal(vi) ORIGINAL SOURCE:(A) ORGANISM: Synthetically derived(xi) SEQUENCE DESCRIPTION: SEQ ID NO:1:LysLeuValGluHisValProGlyArgProValArgHisAlaGlnCys151015Arg(2) INFORMATION FOR SEQ ID NO:2:(i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 22 amino acids(B) TYPE: amino acid(D) TOPOLOGY: linear(ii) MOLECULE TYPE: peptide(v) FRAGMENT TYPE: internal(vi) ORIGINAL SOURCE:(A) ORGANISM: Synthetically Derived(xi) SEQUENCE DESCRIPTION: SEQ ID NO:2:ArgProValArgHisAlaGlnCysArgValCysAspGlyAsnSerThr1 51015AsnProArgGluArgHis20(2) INFORMATION FOR SEQ ID NO:3:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 14 amino acids(B) TYPE: amino acid(D) TOPOLOGY: linear(ii) MOLECULE TYPE: peptide(v) FRAGMENT TYPE: internal(vi) ORIGINAL SOURCE:(A) ORGANISM: Synthetically derived(xi) SEQUENCE DESCRIPTION: SEQ ID NO:3:ArgTyrLysIleThrProArgArgGlyProProThrTyrArg1510(2) INFORMATION FOR SEQ ID NO:4:(i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 14 amino acids(B) TYPE: amino acid(D) TOPOLOGY: linear(ii) MOLECULE TYPE: peptide(v) FRAGMENT TYPE: internal(vi) ORIGINAL SOURCE:(A) ORGANISM: Synthetically derived(xi) SEQUENCE DESCRIPTION: SEQ ID NO:4:AlaArgTyrIleArgLeuArgLeuGlnArgIleArgThrLeu1 510(2) INFORMATION FOR SEQ ID NO:5:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 20 amino acids(B) TYPE: amino acid(D) TOPOLOGY: linear(ii) MOLECULE TYPE: peptide(v) FRAGMENT TYPE: internal(vi) ORIGINAL SOURCE:(A) ORGANISM: Synthetically derived(xi) SEQUENCE DESCRIPTION: SEQ ID NO:5:HisArg AspLeuArgAspLeuAspProIleValThrArgArgTyrTyr151015TyrSerIleLys20(2) INFORMATION FOR SEQ ID NO:6:(i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 9 amino acids(B) TYPE: amino acid(D) TOPOLOGY: linear(ii) MOLECULE TYPE: peptide(vi) ORIGINAL SOURCE:(A) ORGANISM: Synthetically derived(xi) SEQUENCE DESCRIPTION: SEQ ID NO:6:CysAspProGlyTyrIleGlySerArg15(2) INFORMATION FOR SEQ ID NO:7:(i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 20 amino acids(B) TYPE: amino acid(D) TOPOLOGY: linear(ii) MOLECULE TYPE: peptide(v) FRAGMENT TYPE: internal(vi) ORIGINAL SOURCE:(A) ORGANISM: Synthetically derived(xi) SEQUENCE DESCRIPTION: SEQ ID NO:7:ArgTyrValValLeuProArgProValCysPheGluLysGlyMetAsn 151015TyrThrValArg20(2) INFORMATION FOR SEQ ID NO:8:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 17 amino acids(B) TYPE: amino acid(D) TOPOLOGY: linear(ii) MOLECULE TYPE: peptide (v) FRAGMENT TYPE: internal(vi) ORIGINAL SOURCE:(A) ORGANISM: Synthetically derived(xi) SEQUENCE DESCRIPTION: SEQ ID NO:8:ArgIleGlnAsnLeuLeuLysIleThrAsnLeuArgIleLysPheVal151015 Lys(2) INFORMATION FOR SEQ ID NO:9:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 15 amino acids(B) TYPE: amino acid(D) TOPOLOGY: linear(ii) MOLECULE TYPE: peptide(v) FRAGMENT TYPE: internal(vi) ORIGINAL SOURCE:(A) ORGANISM: Synthetically derived(xi) SEQUENCE DESCRIPTION: SEQ ID NO:9:CysGlnAlaGlyThrPheAlaLeu ArgGlyAspAsnProGlnGly151015(2) INFORMATION FOR SEQ ID NO:10:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 18 amino acids(B) TYPE: amino acid(D) TOPOLOGY: linear(ii) MOLECULE TYPE: peptide(v) FRAGMENT TYPE: internal(vi) ORIGINAL SOURCE:(A) ORGANISM: Synthetically derived(xi) SEQUENCE DESCRIPTION: SEQ ID NO:10:SerArgAlaArgLysGlnAlaAlaSerIleLysValAlaValSerAla151015AspArg (2) INFORMATION FOR SEQ ID NO:11:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 5 amino acids(B) TYPE: amino acid(D) TOPOLOGY: linear(ii) MOLECULE TYPE: peptide(v) FRAGMENT TYPE: internal(vi) ORIGINAL SOURCE:(A) ORGANISM: Synthetically derived(xi) SEQUENCE DESCRIPTION: SEQ ID NO:11:IleLysValAlaVal1 5
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Polypeptides derived from domain VI of the amino terminal globule of the A chain of laminin and having sequences of at least about 5 amino acids, and which exhibit cell adhesion and cell spreading capacity are described.
Medical devices such as prosthetic implants, percutaneous devices and cell culture substrates coated w
GOVERNMENT SUPPORT
This invention was made with government support under contract No. CA-29995 by the U.S. National Institutes of Health. The government has certain rights in the invention.
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CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority from U.S. patent application Ser. No. 08/813,363 filed Mar. 7, 1997, entitled “Fishing Surveillance Device”, which claims priority from U.S. Provisional Patent Application Ser. No. 60/013,125, filed Mar. 11, 1996.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] This invention relates to fishing and, more particularly, to an apparatus for viewing fish during fishing and a method for using the apparatus.
[0004] 2. Description of the Prior Art
[0005] In recent years, fishermen have taken advantage of technological advances to improve their performance. These advances include, for example, satellite services that provide up-to-the-minute ocean currents and water temperatures to better locate fish. Utilizing this information, modified radar systems are utilized to detect exact locations on the water and modified sonar is utilized to detect the exact location of fish in the water. Fishing poles are made out of space age materials for strength and sensitivity and computer designed lures imitate the exact motions of the prey they are modeled after.
[0006] In spite of these advances, fishermen still lack specific real time information regarding the fishing environment and the actions of any fish that are present. More specifically, there is no provision for detecting the presence and/or desirability of fish, the attractiveness of bait or lure to the fish, whether the rig is configured properly, whether the fish are striking the bait or merely taking investigatory nibbles, the proper time of applying a hooking yank, whether the fish is hooked and how aggressively the fish should be reeled in.
[0007] Heretofore, prior art solutions have been utilized to locate fish. However, these prior art devices do not enable a fisherman to obtain accurate information about the foregoing real time variables.
[0008] It is, therefore, an object of the present invention to provide a submersible camera that is utilized with a fishing line to detect the presence and desirability of fish, the attractiveness of bait or lure to the fish, whether the rig is configured properly, whether the fish is striking the bait or lure or merely taking investigatory nibbles, the proper time to apply a hooking yank, whether the fish is hooked and how aggressively the fish should be reeled in. It is an object of the present invention to provide a submersible camera that is easily attachable to a fishing line and is easy and entertaining to use. It is an object of the present invention to provide a fishing apparatus that enables a visual record of a fishing catch to be recorded. Still other objects will become apparent to those of ordinary skill in the art upon reading and understanding the following detailed description.
SUMMARY OF THE INVENTION
[0009] Accordingly, I have invented an underwater surveillance apparatus comprising a watertight housing having a transparent part and a video tube received in the watertight housing. The video tube has a light receiving end positioned to view through the transparent part of the watertight housing. A video cable extends from the video tube to a video monitor disposed above the surface of the water. The watertight housing is configured such that the transparent part of the watertight housing is urged in a direction downstream when the watertight housing is submerged in a body of fluid moving relative to the watertight housing.
[0010] An optical lens can be attached to the light receiving end of the video tube and the transparent part of the watertight housing can be disposed at an end thereof.
[0011] A positioning means can be used for positioning the watertight housing in the body of fluid moving relative to the watertight housing. Preferably, the positioning means includes one or more fins attached to the watertight housing for orienting the watertight housing in a body of fluid moving relative to the watertight housing.
[0012] I have also invented a submersible camera for use in viewing fish in a body of water. The camera includes a watertight housing having a transparent end and a video tube received in the watertight housing. The video tube has a light receiving end positioned to view through the transparent end of the watertight housing. A video cable extends from the video tube to a video monitor disposed above a surface of the water. The camera is configured such that, in response to relative movement between the water of the body of water and the watertight housing, the light receiving end of the video tube orients to view in a direction downstream of the watertight housing.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] [0013]FIG. 1 is a side sectional view of a submersible camera;
[0014] [0014]FIGS. 2 a - 2 c are side sectional views of the submersible camera of FIG. 1 attached to a video cable and an adjustment cable for adjusting the angle of the submersible camera;
[0015] [0015]FIG. 3 is an illustration of the submersible camera of FIG. 1 attached to a fishing line and suspended in a body of water behind a moving boat; and
[0016] [0016]FIG. 4 is an illustration of the submersible camera of FIG. 1 attached to a fishing line and suspended in a body of moving water behind a stationary boat.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0017] A submersible camera 2 is connected to a video monitor 4 via a video cable 6 . A video recorder 8 is optionally attached to the video monitor 4 for recording visual images displayed thereon. A microphone (not shown) is optionally attached to video recorder 8 to record narration of a human operator.
[0018] The submersible camera 2 includes a torpedo-shaped housing 9 having a support eyelet 10 attached adjacent one end thereof for attaching the housing 9 to the video cable 6 . A fin 12 is attached to the end of the housing 9 opposite the support eyelet 10 . The fin 12 extends radially outward from the housing 9 . Attached to an edge of the fin 12 positioned away from the housing 9 is a swivel eyelet 14 .
[0019] The side of the fin 12 adjacent the end of the housing 9 includes a slot 15 adapted to receive a light source 16 therein. The light source 16 is a submersible lightbulb or a lightbulb contained in a transparent housing (not shown).
[0020] A video tube or camera 18 is positioned inside the housing 9 with the longitudinal axis of the video tube 18 parallel with the longitudinal axis of the housing 9 . Housing 9 is adapted to be watertight so that fluid, and in particular water, does not enter the housing 9 and come into contact with the video tube 18 . The video tube 18 contains processing electronics (not shown) to convert video images received thereby to electronic signals. The electronic signals from the video tube 18 are transmitted to the video monitor 4 via the video cable 6 . The video cable 6 is also utilized to provide power to the video tube 18 from a power supply 19 positioned remote from the housing 9 . Alternatively, a power supply 19 ′ is positioned in the housing 9 to provide power to the video tube 18 . The power supply 19 or 19 ′ can also provide power to the light source 16 and other gauges or devices carried by housing 9 .
[0021] The end of the video tube 18 adjacent the fin 12 has a lens assembly 20 positioned thereon. The lens assembly 20 may include a fixed or replaceable lens for focusing the light received thereby onto a receiving array and/or an adjustable iris for controlling the amount of light received by the receiving array. The lens, adjustable iris and receiving array are omitted from FIG. 1 for simplicity. The end of the housing adjacent the lens assembly 20 is transparent so that light can pass therethrough from outside the housing 9 for receipt by the lens assembly 20 .
[0022] With reference to FIGS. 2 a - 2 c , an adjustment cable 22 is attached between a position on the video cable 6 between the support eyelet 10 and the video monitor 4 and the swivel eyelet 14 . The length of the adjustment cable 22 and the attachment of the adjustment cable 22 to the video cable 6 may be fixed. Alternatively, the adjustment cable 22 can be extended between the swivel eyelet 14 and an adjustment position above the surface of the water via a cable eyelet 24 attached to the video cable 6 between the support eyelet 10 and the video monitor 4 . In this embodiment, the angle of the camera 2 to view the bait receiving end of the fishing line 30 (shown in FIGS. 3 and 4) can be adjusted by adjusting the length of the adjustment cable 22 between the cable eyelet 24 and the swivel eyelet 14 .
[0023] With reference to FIG. 3, the submersible camera 2 is suspended in a body of water via the video cable 6 attached to a downrigger 28 which is attached to a boat B. Also suspended in the water is a fishing line 30 having a lure or bait 31 received at a bait receiving end thereof. Attached between swivel eyelet 14 and the fishing line 30 is a release clip 34 . The release clip 34 releasably secures the submersible camera 2 to the fishing line 30 so that the submersible camera 2 can observe the bait receiving end of the fishing line 30 when the camera 2 and the bait receiving end of the fishing line 30 are submerged. The release clip 34 enables the submersible camera 2 and fishing line 30 to be separated. More specifically, the release clip 34 separates the fishing line 30 from the submersible camera 2 in response to the application of a hooking yank to the fishing line 30 . In this manner, once a fish is hooked to the bait receiving end of the fishing line 30 , the submersible camera 2 can be disengaged from the fishing line 30 to avoid potential damage to the submersible camera 2 or entanglement with the video cable 6 by the fish F trying to free itself from the fishing line 30 .
[0024] By observing the video monitor 4 , the fisherman can determine the appropriate moment to apply a hooking yank. Moreover, by observing the bait 31 , the fisherman can assess the desirability of the lure or live bait 31 to the fish F. As shown in FIG. 3, the housing 9 of the submersible camera 2 may include additional fins 12 ′ which enable the angle of the camera 2 to be controlled. These extra fins 12 ′ may be fixed in position on the housing 9 or may be adjustable on the housing 9 to enable the angle of the housing 9 to be adjusted to suit a desired fishing environment, trolling speed or water current speed.
[0025] With reference to FIG. 4, boat B is held stationary on the surface of the water via anchor A. The submersible camera 2 is suspended in the body of water via the video cable 6 attached to the downrigger 28 . A sinker S attached to support eyelet 10 is utilized to help maintain the position of the submersible camera 2 in the body of water. The fishing line 30 is also suspended in the body of water. The fishing line 30 has a lure or bait 31 attached to a bait receiving end thereof and is connected to a fishing pole 32 at an end opposite the bait receiving end. In this embodiment, the adjustment cable 22 is connected between the swivel eyelet 14 and a position on the boat B via cable eyelet 24 . The release clip 34 is releasably attached between the submersible camera 2 and the fishing line 30 . A release line 40 is attached between the release clip 34 and a position above the surface of the water and, preferably, on the boat B. Applying tension of a sufficient extent to the release line 40 causes the release clip 34 to release the fishing line 30 from the submersible camera 2 . In the absence of tension of sufficient extent on the release line 40 , the submersible camera 2 and the fishing line 30 remain connected via the release clip 34 . In this manner, when a fish F is hooked on the bait receiving end of the fishing line 30 , the struggle of the fish F against the fishing line 30 can be observed and/or recorded as desired.
[0026] In use, the fishing line 30 is releasably connected to the submersible camera 2 . The camera 2 and the fishing line 30 are submerged so that the submerged camera 2 orients under the influence of water current C to view the bait receiving end of fishing line 30 and, more specifically, the lure or bait 31 attached to the bait receiving end of the fishing line 30 . The submersible camera 2 transmits visual pictures of the bait receiving end of the fishing line 30 to the video monitor 4 for observation by a fisherman. At an appropriate time, a hooking yank is applied to the fishing line 30 to hook a fish thereon and the fishing line 30 is released from the submersible camera 2 . The fishing line 30 is released from the submersible camera 2 by the application of the hooking yank to the fishing line 30 or by a fish F striking the lure or live bait 31 received on the bait receiving end of the fishing line 30 . Alternatively, the fishing line 30 is released from the submersible camera 2 by applying tension to a release line 40 connected to the release clip 34 attached between the submersible camera 2 and the fishing line 30 . Visual images displayed on the video monitor 4 can be recorded by a video recorder 8 . Moreover, the angle of the submersible camera 2 relative to the bait receiving end of the fishing line 30 can be adjusted via the adjustment cable 22 .
[0027] As can be seen from the foregoing, the present invention provides a visual indication of the presence and desirability of fish F, the attractiveness of the lure or bait 31 to the fish F, whether the fish F is striking the lure or bait 31 or merely taking investigatory nibbles, the proper time to apply the hooking yank, whether the fish F is hooked, and how aggressively the fish F should be reeled in.
[0028] The above invention has been described with reference to the preferred embodiments. Obvious modifications, combinations and alterations will occur to others upon reading and understanding the preceding detailed description. For example, the housing 9 can be permanently attached to the fishing line 30 . Moreover, the present invention can be utilized to fish from freestanding structures such as a pier or bridge. Moreover, if an undesirable fish F approaches the lure or bait 31 , the fisherman can move the lure or bait 31 in an undesirable manner to scare the undesirable fish F away. It is intended that the invention be construed as including all such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof.
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An underwater surveillance apparatus includes a watertight housing having a transparent part and a video tube received in the watertight housing. The video tube has a light receiving end positioned to view through the transparent part of the watertight housing. A video cable extends from the video tube to a video monitor disposed above a surface of the body of water. The watertight housing is configured such that the transparent part of the watertight housing is urged in a direction downstream when the watertight housing is submerged in a body of fluid moving relative to the watertight housing.
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This is a continuation of application Ser. No. 322,366, filed Jan. 10, 1973, and now abandoned.
BACKGROUND OF THE INVENTION
The catalytic activity of tertiary amines in epoxy/anhydride compositions has been previously taught in U.S. Pat. No. 3,052,650. A particular object of the invention described therein is the formation of liquid epoxy resin compositions having extended pot life at normal room temperatures, which compositions may then be cured to a hard and tough state by heating for 1 or 2 hours at elevated temperatures on the order of 250° F.
The soluble tertiary amines in the epoxy/anhydride compositions serve to catalyze the curing of the overall blend to a hard and tough condition during the application of elevated temperature. There is a desirability, for example in connection with "in the field" application, for a system that will cure at ambient temperatures to a hardened state. It would also be desirable, particularly in such field applications, to move to substances that present reduced hazards in the field, and commensurately provide products involving minimum toxicity characteristics.
SUMMARY OF THE INVENTION
It has now been found that certain high-functional polymercaptan resins can be readily blended along with or in the epoxy resin and the anhydride to form blends adapted for ambient temperature curing. Such compositions can be easily and quickly mixed and applied in "on site" conditions; they further have the added advantage of reducing the toxicity problem associated with tertiary amines during such blending and application. Other desirable characteristics include cure hardness achieved at ambient temperature that is comparable to cure hardness for competitive systems which is arrived at under elevated temperature condition. Further characteristics include the option of obtaining lighter colored products as well as desirable properties for electrical applications for the cured products.
Broadly then, the present invention is directed to an epoxy resin composition adapted for room-temperature, accelerated and autogenous curing; such composition has a continuous liquid phase and comprises, among other components, a substance selected from the group consisting of polyglycidyl ether of a polyhydric phenol having a ratio of the hydroxyl groups to the 1,2-epoxy groups of not above about 2.5:2, cycloaliphatic epoxides, polyglycidyl ethers of novolac resins, and mixtures thereof. The composition components further include polycarboxylic acid anhydride in an amount sufficient to provide about 0.5-2 anhydride groups per 1,2-epoxy groups, which amount of anhydride is uniformly dispersed in the continuous liquid phase.
The last key component of the composition is liquid polymercaptan resin having an average SH functionality of greater than 2.5 and an average molecular weight between about 300-5,000; additionally, the resin is present in uniform dispersion in the liquid phase and in a catalytic amount within the range of from above about 3 to about 150 weight parts per 100 weight parts of the component named first hereinabove. The polymercaptan resin, moreover, has hydroxyl functionality in addition to the SH functionality. The three key components produce blends that are homogeneous, and cure autogenously, at ambient temperature.
In one aspect, the invention is further directed to the method of preparing a cured, epoxy resin composition, which cured composition is arrived at through accelerated, autogenous curing of the hereinabove described blend.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The epoxy resin component for the composition is contributed by one or more substances containing the 1,2-epoxy linkage. Such components can be supplied completely by substances that are epoxy ethers produced by the interreaction of an epihalohydrin with polyhydroxy compounds, and especially such reaction with polyhydroxy phenols. These particular epoxy resins therefore further refer to polyglycidyl ethers of polyhydric phenols. Such polyglycidyl ethers of polyhydric phenols must have, for purposes of this invention, a ratio of the hydroxyl groups to the 1,2-epoxy groups of not above about 2.5:2. A useful substance representative of these particular epoxy resins is 2,2-bis [4-(2',3'-epoxy propoxy) phenyl] propane.
The epoxy resin component can further be supplied by cycloaliphatic epoxides. These are typically alicyclic diepoxides produced by the reaction of a peracid, such as peracetic acid, and an alicyclic carboxylate. The carboxylate in turn can be prepared by condensation of an aldehyde; for example, a suitable carboxylate for subsequent reaction with a peracid is prepared by the Tischenko condensation of tetrahydrobenzaldehyde.
An additional useful epoxy resin component for the composition can be contributed by polyglycidyl ethers of novolac resins. The novolac resins are produced by reaction of formaldehyde with a phenol, for example alkyl phenols or aryl phenols or polyhydroxy phenols. The resulting polyglycidyl ethers are then prepared by the reaction of an epihalohydrin, most usually epichlorohydrin. It is further contemplated to use mixtures of these epoxy resin substances to supply the epoxy resin component for the autogenously curing composition.
These epoxy resins to be most useful are liquid at ambient temperature and can be readily blended with additional ingredients to form hardened compositions. The known class of agents for this purpose that are useful in this invention are the polycarboxylic acid anhydrides, i.e., other than the monocarboxylic acid anhydrides. However, the use of such an anhydride should be accompanied with a further catalytic agent, in this case the high functional polymercaptan resins.
It is known with the epoxy/anhydride systems that if the polyglycidyl ethers of polyhydric phenol epoxy resins have a ratio of the hydroxyl groups to the 1,2-epoxy groups of above about 2.5:2, such resins will be solid at ambient temperature and undesirably intractable at initiating a reasonably satisfactory epoxy-anhydride reaction even with varying amounts of catalyst. If the polycarboxylic acid anhydride is diabasic, about 0.5-2 mols of anhydride per equivalent of epoxide will be useful. But it is recognized that with a dianhydride such as pyromellitic dianhydride, lesser amounts may be useful.
For enhancing the curing of the component blend, the anhydride is advantageously one that is liquid at ambient temperature and may be readily and easily dispersed in the epoxy resin to quickly form a homogenous blend. Such blends for best accelerated autogenous curing are those obtained by dissolving the anhydride in the epoxy resin. Hence, preferably, the anhydride is one which can be readily dissolved in such epoxy resin at ambient temperature.
As many of the useful anhydrides are solids at normal temperatures and therefore difficult to blend with a liquid epoxy resin, a known technique that may be employed in the practice of this invention is the pre-blending of anhydrides to form liquid eutectic mixtures. Thus, with an anhydride such as maleic anhydride which is normally a solid, i.e., melting under normal conditions at about 52° C., such can be employed in a eutectic mixture. For example, 25 weight parts of such anhydride with 75 weight parts of methyl endomethylene tetrahydrophthalic anhydride will form a liquid eutectic mixture at ambient temperatures.
Another technique for handling a solid anhydride substance and that can be useful in forming a component blend having a continuous liquid phase, as well as one which will cure at ambient temperature, is to first heat the solid anhydride and thereby liquify it at elevated temperature. At such temperature the resulting liquified substance can be blended with epoxy resin, or may be blended with the liquid polymercaptan resin, or both. Such technique is highly serviceable so long as a homogenous dispersion of ingredients results, and provides a dispersion having a continuous liquid phase when the blend of components is permitted to cool down to normal temperatures. In this technique, so long as the above mentioned criteria are established, the liquified anhydride could be, for example, blended at elevated temperature with liquid epoxy, the blend cooled to ambient temperature and then the polymercaptan resin subsequently admixed with the blend.
In general, the anhydrides that may be used and have been used in the practice of the invention include such anhydrides that are in liquid condition under normal conditions as well as such anhydrides that are solid under these conditions but may be useful in eutectic mixtures. As some commercially available mixtures are proprietary, it is not ostensibly feasible to provide an exhaustive list of all useful substances. However, without attempting to be complete, useful anhydrides include phthalic anhydride, hexahydrophthalic anhydride, methyl endomethylene tetrahydrophthalic anhydride, tetrahydrophthalic anhydride, maleic anhydride, tetramethylene maleic anhydride, dodecenylsuccinic anhydride, pyromellitic dianhydride, hexachloroendomethylene tetrahydrophthalic anhydride, trimellitic anhydride, and mixtures thereof.
The polymercaptan resin component is supplied by liquid polymeric materials having an average SH functionality of greater than 2.5. Preferably, for enhancing the autogenous cure at ambient temperature, such resin has SH functionality of about 3 or more, for example 6 or more, although typically such is below about 6 for economy. Also, such resins have hydroxyl functionality; for cure enhancement, this hydroxyl functionality is preferably on the carbons that are in the position alpha to the carbon atoms bearing the SH functionality. Further, the polymers preferably have 2 or more hydroxyl groups per molecule, e.g., 2-5 such groups per molecule.
Exemplary polymercaptan resins have been shown, for example, in U.S. Pat. Nos. 3,361,723 as well as 3,472,913. Moreover, as has been described in some detail in the last mentioned U.S. patent, exemplary polymercaptan resins can also be prepared in accordance with the teachings of U.S. Pat. Nos. 3,258,495 and 3,278,496, and ostensibly under certain steps disclosed in U.S. Pat. No. 2,581,464. As will be seen from a review of this exemplary U.S. Patent art, the molecular precursor to the polymercaptan resin typically contains three or more groups of the following structure --CH(OH)CH 2 Cl. From this type of structure, mercaptan termination is derived by replacing the chloride with sulfhydrate, as for example reaction with an alkali metal sulfhydrate such as sodium sulfhydrate. This reaction does not seem to disturb the hydroxyl constituency on the carbon atom that is in the alpha position to the carbon atom on which the replacement reaction takes place. These polymercaptan resins, in liquid condition, have molecular weight of between about 300-5,000, and most typically between about 500-3,000. Such resins are virtually, to completely, free from polysulfide linkages.
For economy, a particularly preferred polymercaptan is one prepared from polyepoxides such as polyepoxy-containing polymeric reaction products prepared from a halogen-containing epoxide reacted with an aliphatic polyhydric alcohol. The polymercaptan resin is typically present in the blend of components in amounts from above about 3 to about 150 weight parts, basis 100 weight parts of the epoxy resin component. Less than about 3 weight part polymercaptan resin is generally insufficient to achieve a desirably cured composition, while greater than 150 weight parts of the polymercaptan resin can be uneconomical. Typically, the polymercaptan resin is present in an amount between about 5-50 weight parts, and preferably in an amount of at least 10-35 weight parts, basis 100 weight parts epoxy resin. In addition to the above discussed materials, the resinous blend may most usually contain other resinous materials as well as substances exemplified by pigments, fillers, brighteners, plasticizers, diluents, dyes, as well as other additives or components which may be formulated into such compositions.
When the blend of components is prepared, such blends even in fresh condition are ready for immediate and desirable autogenous curing at ambient temperatures. Such compositions thus exhibit particular utility for on site application and will achieve rapid curing, i.e., within only several days time, even at temperatures below 40° C. However, as has been more particularly taught hereinafter in the examples, ambient temperatures on the order of only 20°-30° C. are needed for autogenous curing of prepared blends. Such blends further have a continuous liquid phase that provides ease of application after on-site preparation. All three key ingredients may contribute to such liquid phase, e.g., the anhydride can be one that dissolves in the epoxy resin component and this resulting solution is then intimately mixed with liquid polymercaptan resin. Or the components that are not directly contributing to the liquid of the continuous phase can be dispersed therein and such phase is contributed to or supplied by the other components.
The following examples show ways in which the invention has been practiced but should not be construed as limiting the invention.
EXAMPLE 1
The polymercaptan resin employed is a mercaptan terminated liquid polymer having a viscosity of about 11,400-11,800 centipoises as measured at 25°C. with a Brookfield Viscometer Model RVT using a No. 6 spindle at 20 r.p.m. This resin further has a mercaptan equivalent, expressed as milliequivalents of SH functionality per gram of resin, of about 3.58 as measured by iodimetric titration, a specific gravity of 1.15, and an average of about 3 --OH groups per molecule. The resin is prepared in accordance with the teachings of U.S. Pat. No. 3,278,496 by reacting a hydroxy terminated liquid polyoxyalkylene glycol polymer having a molecular weight of about 400 with a halogenated epi-compound and then subsequently with a sulfur-contained reactant. The resin contains about three SH groups per molecule and has OH groups on the carbons that are in the position alpha to the carbon atoms having the SH functionality.
The liquid epoxy resin used is a light straw-colored, medium viscosity, unmodified epoxy resin that is capable of being cured by anhydrides. The liquid epoxy resin has a viscosity of 12,000-16,000 centipoises at 25°C, an epoxy value of 0.51-0.54 equivalent per hundred grams, and a weight per gallon of 9.6-9.8 lbs. For comparative testing, the curing agent employed, as a replacement for the polymercaptan resin, is 2,4,6-tris(dimethylaminomethyl) phenol (Amine catalyst).
For each blend of materials, and the ingredients for each blend are more particularly shown in the table below, the anhydride employed is methyl endomethylene tetrahydrophthalic anhydride (META anhydride) which is a liquid material at ambient temperature. In the table below the various blends of ingredients shown are prepared by simply mixing the ingredients together with vigorous agitation in suitable containers; the blends of ingredients are thereafter permitted to cure under the conditions shown. Representative comparative samples from each of the cured blends, including samples from blends cured under varying conditions, all as shown on table below, are then subjected to a durometer hardness test.
For this test a Type D instrument is used, which is manufactured by Shore Instrument and Manufacturing Co. Inc., and which instrument has been shown an ASTM D2240-68, 1972 edition, part 27, page 658-661. For convenience, the hardness data received from such an instrument is referred to herein as the "Shore D" hardness.
Also, as shown in the table below, representative, comparative samples of each cured blend are immersed for varying lengths of time in water. This is distilled water that is maintained at 75°F with no agitation. Following immersion of samples in water, the samples are removed, dried to remove surface water, then weighted and thereafter subjected to the Shore D hardness test. The results of such testing have been reported in the table.
TABLE 1______________________________________Ingredients, BlendsWeight Parts 1 2 3 4 5______________________________________Epoxy Resin 100 100 100 100 100Polymercaptan Resin0-0- 15 20 25META Anhydride 85 85 76 74 71Amine Catalyst0- 30-0-0- Shore D Hardness7-Day Cure at 75°F. no cure 84 82 86 86After Water Immersion: For: 1 month -- 88 85 87 88 3 months -- 86 88 88 87 6 months -- 85 88 87 872-Hours Cure at 285°F. no cure 89 80 86 87After Water Immersion: for: 1 month -- 89 85 87 86 3 months -- 88 82 85 86 6 months -- 88 82 85 867-Day, 75°CureAfter Water Immersion: Percent Change in Weight______________________________________ For: 1 month -- +1.7 +0.4 +0.5 +0.53 months -- +4.5 +0.8 +0.8 +0.9 6 months -- +9.2 +1.1 +1.2 +1.22-Hour, 285°F. CureAfter Water Immersion:______________________________________ For: 1 month -- +0.4 +0.4 +0.5 +0.5 3 months -- +0.6 +0.9 +0.9 +0.8 6 months -- +0.8 +1.2 +1.2 +1.1______________________________________
As can be seen from the results recorded in the table above the anhydride alone, i.e., the META anhydride in Blend 1, is incapable of curing the epoxy resin either under the conditions of room temperature or at the elevated 285°F. However, the amine catalyst used in recommended manner, and the polymercaptan resin are each capable of providing curing of the epoxy resin.
The subsequent water submersion tests disclose that the blend cured at room temperature with the amine catalyst will provide for an undesirable rapid absorption of water in the only three months of submersion testing. On the other hand, the polymercaptan resin accelerator, and even for the room temperature cured compositions, i.e. cured at 75°F., provides for more desirable, minimal water absorption. Such water absorption is equated to the amine catalyzed composition absorption, but only when such amine composition is cured at augmented temperature, i.e., at the elevated 285°F.
EXAMPLE 2
By using the polymercaptan resin of Example 1 and the epoxy resin of Example 1 in the manner of Example 1, additional blends are prepared as shown in the table below. For these blends, however, the anhydride employed is dodecenyl succinic anhydride (DDS anhydride). Also, as shown on the table below, a comparative blend is prepared that contains the amine catalyst in recommended amount. Also reported in the table below are the results for the Shore D hardness testing and for the water submersion testing, both conducted in the manner discussed in Example 1.
TABLE 2______________________________________Ingredients, BlendsWeight Parts 1 2Expoxy Resin 100 100Polymercaptan Resin0- 50DDS Anhydride 140 93Amine Catalyst 30- Shore D Hardness7-Day Cure at 75°F. 76 78After Water Immersion______________________________________ For: one month 83 79 three months 84 81 six months 83 812-Hour Cure at 250°F. 83 81After Water Immersion______________________________________ For: one month 81 80 three months 82 82 six months 82 827-Day, 75°F. Cure Percent Change In Weight______________________________________ Plus: one month in water +0.6 +0.6 three months in water +0.9 +1.0 six months in water +1.2 +1.12-Hour, 250°F. Cure______________________________________ Plus: one month in water +0.3 +0.5 three months in water +0.5 +0.7 six months in water +0.5 +1.0______________________________________
The tabulated results show that results obtained through use in a comparative blend of commercial amine catalyst, and for elevated temperature curing, are essentially consistently duplicated, even at low temperature curing for compositions which are free from amine catalyst but which contain the greatly extended amount of the polymercaptan resin.
EXAMPLE 3
By using 100 parts-by-weight of the epoxy resin of Example 1 and 85 parts-by-weight of the anhydride of Example 1, a composition ("Control") is prepared for testing. Further, by blending 25 weight parts of the polymercaptan resin of Example 1 with an additional batch of the Control, there is then prepared a new composition ("High Functional Polymercaptan") for testing. In addition to the Control blend, another comparative blend is formulated for testing with polymercaptan resin that is not contemplated for use in compositions of the present invention.
This comparative polymercaptan resin is a water-white liquid having a pH of 5.8, a molecular weight of about 6,000 and a mercaptan equivalent, expressed as milliequivalents of SH functionality per gram of resin of 0.35. However, this comparative polymercaptan resin has an average SH functionality per molecule of only about 2.3. Along with 100 weight parts of the Example 1 epoxy resin and 75 weight parts of the Example 1 anhydride, there is used 25 weight parts of this comparative polymercaptan resin to form a composition ("Comparative Polymercaptan") for testing.
A further composition not illustrative of the present invention is prepared by blending with 100 weight parts of the Example 1 epoxy and 85 weight parts of the Example 1 anhydride, 25 weight parts of a polysulfide liquid polymer. The resulting comparative composition ("Comparative Polysulfide") contains 25 weight parts of a commercially available polysulfide liquid polymer manufactured by Thiokol Chemical Corporation and designated as their LP-3. Such liquid polymer contains disulfide linkages and therefore does not prepare compositions contemplated in the present invention. Further, this polymer has an average molecular weight of about 1,000, a viscosity in poises at 25°C of 10, and a specific gravity (20°/20°) of 1.27.
Cures of selected samples of all these resulting blends, including the High Functional Polymercaptan blend which is the only composition that is representative of the present invention, as shown in the table below, are attempted. On some samples such attempted cure is at room temperature condition. Additionally, where more than a liquid is obtained during attempted cure, Shore D hardness testing is conducted on the test blends in the manner discussed in Example 1. Results for this hardness testing are also shown in Table 3 below.
TABLE 3__________________________________________________________________________ Cure Condition & Hardness Cure Condition & Hardness Room Temp.Blend 6 Hrs. at 270°F Shore D One Week Shore D__________________________________________________________________________Control liquid N.M. liquid N.M.Comparative viscous N.M. liquid N.M.Polymercaptan liquidComparative cured 75 skinned N.M.Polysulfide liquidHigh Functional cured 85 cured 65Polymercaptan__________________________________________________________________________ N.M. = Not measurable owing to liquid condition.
The tabulated results with the Control clearly indicate that some catalyst needs to be present to provide for curing of the epoxy/anhydride blends even under elevated temperature conditions for an extended period. The results further show that although elevated temperature conditions may provide for cured products among comparative blends, only the blended composition representative of the present invention will achieve ambient temperature cure within the 1 week test period. It is further noteworthy that the Comparative Polymercaptan does not provide for a cured blend either at ambient temperature for 1 week or at elevated temperature in 6 hours.
EXAMPLE 4
A test blend is prepared from 88 weight parts of the anhydride of Example 1 with the 100 weight parts of an epoxy novolac resin. This resin is an amber-colored, polyfunctional thermosetting resin having an epoxide functionality per molecule of about 2.0. It has a viscosity of 14-20 poises at 52°C., a density of 1.21 grams per milliliter at 20°C., and a weight per epoxide of 172-179 grams. The resulting composition (Control,) of epoxy and anhydride without more, is used for control purposes.
An additional blend containing 100 weight parts of the just-described epoxy novolac resin and 88 weight parts of the Example 1 anhydride is further prepared to also contain 1.5 weight parts of benzyl dimethyl amine catalyst. This blend ("Amine Catalyst") is used for comparative purposes as representative of formulations catalyzed with amine.
A composition illustrative of the present invention ("First High Functional") is prepared by using 25 weight parts of the polymercaptan resin of Example 1 with 100 weight parts of the epoxy novolac resin and 88 weight parts of the Example 1 anhydride. An additional formulation of the present invention ("Second High Functional") is prepared with 25 weight parts of the polymercaptan resin of Example 1 and 100 weight parts of the epoxy novolac resin. But this composition contains only 73 weight parts of the Example 1 anhydride.
As shown in Table 4 below, elevated temperature cures for 6 hours are attempted on samples from all these compositions. Also, as shown in the table below, Shore D hardness testing results are obtained for compositions cured under such conditions. Further, selected samples of these blends are also chosen for attempted curing in 1 week at room temperature. Results of such attempts to cure are also shown in Table 4 below, along with the Shore D hardness testing results where such results are obtainable.
TABLE 4__________________________________________________________________________ Cure Condition & Hardness Cure Condition & Hardness 6 Hours One WeekBlend at 270°F. Shore D Room Temp. Shore D__________________________________________________________________________Control liquid N.M. liquid N.M.Amine Catalyst cured 87 soft gel N.M.First High cured 87 cured 50FunctionalSecond High cured 87 cured 60Functional__________________________________________________________________________ N.M. = Not measurable owing to liquid condition.
The above tabulated results with the Control demonstrate the necessity for catalyzing the epoxy/anhydride system and further that such catalyzing with a representative amine catalyst at recommended amount can be effective under elevated temperature cure condition. However, such amine catalyst, as reported in the table, is not readily effective at ambient temperature. But the blends containing high functional polymercaptan resin, thus representative of the present invention, are cured within one week at ambient temperature.
Further ambient temperature cures are obtained for compositions containing 25-50 weight parts of the polymercaptan resin of Example 1 with 75 weight parts of the anhydride of Example 1 but employing 100 weight parts of epoxy resin that is representative of a cycloaliphatic epoxy resin. Such ambient temperature curing, although not achieved as rapidly as with the above described epoxy novolac resin, is nevertheless obtained at room temperature where the representative cycloaliphatic epoxy resin is an alicyclic diepoxy adipate resin. This particular resin has a viscosity in centipoises at 25°C of 900, a weight per epoxide of 213 grams, and an epoxy value of 0.47 equivalents per 100 grams. Such compositions containing high functional polymercaptan resin plus anhydride and with the cycloaliphatic epoxy resin are also cured, as with conventionally catalyzed epoxy/anhydride systems, at elevated temperature.
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Liquid, high-functional polymercaptan resins employed typically in sealants and adhesives, show excellent catalytic activity for preparing cured epoxy resin compositions from epoxy/anhydride systems. Blends of the epoxy resin with anhydrides and the high functional polymercaptan resins are adapted for room temperature curing into hard resinous compositions. Such compositions cured at ambient temperature show desirable hardness and achieve other characteristics such as reduced water absorption.
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This application is a continuation-in-part of Ser. No. 10/712,667, filed Nov. 13, 2003, now abandoned.
FIELD OF THE INVENTION
The present invention relates to method of applying a silicone caulking compound.
BACKGROUND OF THE INVENTION
The very properties which make silicone caulking compounds effective for caulking, make them difficult to apply with an attractive desired result. As silicone caulking compounds are tacky, they tend to stick to a surface. This property helps make an effective moisture seal. However, this same property tends to result in the silicone caulking compound being smeared over the seam or the sealing surface leaving a cosmetically unattractive finish.
SUMMARY OF THE INVENTION
What is required is a simpler method of applying silicone caulking compound to obtain a cosmetically attractive finish.
According to the present invention there is provided a method of applying a silicone caulking compound. A first step involves applying a bead of silicone caulking compound to a surface. A second step involves spraying a surfactant solution on the bead of silicone caulking compound. A third step involves wiping excess silicone caulking compound from the surface. The surfactant applied to the surface “lubricates” the surface to prevent adhesion of the silicone caulking compound to the undesired surface areas when excess material is wiped away, thereby preventing smearing.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other features of the invention will become more apparent from the following description in which reference is made to the appended drawings, the drawings are for the purpose of illustration only and are not intended to in any way limit the scope of the invention to the particular embodiment or embodiments shown, wherein:
FIG. 1 is a perspective view of a method applying silicone caulking compound to a surface according to the teachings of the preferred method;
FIG. 2 is a perspective view of the method illustrated in FIG. 1 , wherein a surfactant is sprayed on silicone caulking compound; and
FIG. 3 is a perspective view of the method illustrated in FIG. 1 , wherein excess silicone caulking compound is wiped from a surface.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The preferred method will now be described with reference to FIGS. 1 through 3 . Referring to FIG. 1 , there is illustrated a method of applying a silicone caulking compound 10 which includes applying a bead of silicone caulking compound 12 to a surface 14 . Surface 14 to which silicone caulking compound 12 is to be applied should be smooth, dry, and free of all debris, including any previous caulking prior before the application of silicone caulking compound 12 . In the illustrated method 10 , a caulking tube 16 with an application tip 18 is used for applying bead of silicone caulking compound 12 , however it will be appreciated that a caulking gun could also be used.
Referring to FIG. 2 , a surfactant 20 is sprayed on bead of silicone caulking compound 12 before bead of silicone caulking compound 12 begins to set. Referring to FIG. 3 , after silicone caulking compound 12 has been sprayed with surfactant 20 , excess silicone caulking compound 12 is wiped from surface 14 . In illustrated method, a cloth 22 is used to wipe excess silicone caulking compound 12 , however it will be appreciated that one could use a finger or other means could be used. It will also be appreciated that if silicone caulking compound is to be applied to a seam between two or more surfaces 14 , then bead of silicone caulking compound 12 must come into contact with all of surfaces 14 . No further silicone caulking compound 12 may be added after the spraying of surfactant 20 . Silicone caulking compound 12 is then allowed to set for a period of 4 to 10 hours.
Use
The use of the method of applying a silicone caulking will now be described with reference to FIGS. 1 through 3 . Referring to FIG. 2 , with the method described above, surfactant 20 that is applied to surface 14 “lubricates” surface 14 to prevent adhesion of silicone caulking compound 12 to surface 14 . Referring to FIG. 3 , excess silicone caulking compound 12 may then be wiped away. Spreading out or smearing is prevented as silicone caulking compound 12 cannot adhere to surface 14 after it has been sprayed with surfactant 20 . It will be appreciated that a finger or other wiping device could also be used to wipe excess silicone caulking compound 12 . The excess silicone that is removed is not sticky or tacky and can be readily transferred, without mess, to a rag or paper towel for disposal.
Test Results
Surfactants are present in soaps and detergents. Often the word detergent is used interchangeably with surfactant. Surfactants are classified depending upon their charge. Anionic surfactants carry a negative charge. Cationic surfactants carry a positive charge. Nonionic surfactants are neutral, without either a positive or negative charge. In original formulations cationic surfactants were used with beneficial results. It was speculated that the positive charge of the cationic surfactants made them better suited for this particular application. The objective of this study was to evaluate anionic, cationic and nonionic surfactants at different concentrations for their beneficial effect in this application.
Silicone Caulking Material
The silicone caulking material used in this study was a standard white interior grade intended for bathroom applications. The product was manufactured by General Electric Co. and was used as received.
Ceramic Tile
The performance of the various surfactants as an aid in the application of silicon caulking was evaluated on three prepared surfaces. The surfaces were prepared by mounting a single row of ceramic tiles (˜3″ squares) near the edge of a wooden support. Two wooden supports were then attached so as to form a right angle between the ceramic tiles and to bring the ceramic tiles into close proximity. The length of the right angle space between the ceramic tiles was about 75 cm.
Three different surfaces were employed for the evaluation of the materials: tiles with a smooth ceramic surface, tiles with a smooth ceramic surface where the right angle corner between them had been covered with a layer of masking tape, and tiles which had a rough textured surface. The silicone caulking was then applied to the right angle space between the tiles using a manual applicator standard to the industry.
Before each experiment, the surface of the ceramic tiles was thoroughly cleaned with water followed by acetone. Fresh masking tape was used for each experimental surface involving masking tape.
Evaluation Procedure
Preliminary Observations—No Surfactant Applied
The silicone caulking was pumped, using the manual applicator, into the right angle area between the ceramic tiles. In this way a bead some 1/4 ″ in diameter or so was formed in the right angle space between the tiles. When the finger was used in an effort to smooth the silicone caulking, and thus remove excess silicone caulking, it was found that the silicone caulking stuck to the finger and was difficult to remove. In addition, the silicone caulking smeared onto the area of the ceramic adjacent to the right angle space where the silicone caulking had been applied and it was found to be difficult to remove the silicone caulking from this area. Finally, the surface of the resulting silicone caulking bead had a rough appearance. In summary, the procedure resulted in a final bead of unattractive appearance and it was difficult to remove excess caulking from tooling and the ceramic tile.
Observations—Surfactant Applied
In order to evaluate the beneficial effect of the various surfactant solutions on the application of the silicone caulking, the silicone caulking was applied to the surfaces as described above. The surfactant solution was then sprayed onto the area where the silicone caulking had been applied using a mist applicator of the type commonly used in the application of a window cleaner. This application covered the silicone caulking with surfactant solution along with adjacent areas of the ceramic tile. Typically excess surfactant solution was applied. Finally, the finger was used to smooth out the applied silicone caulking and the result noted.
Characteristics evaluated were as follows:
Ease of removal of excess silicone caulking from the finger Smoothness of surface and uniformity of the resulting silicone caulking bead Ease of removal of excess silicone caulking from areas of the ceramic tile surface near the final bead.
Surfactant Solutions
In order to evaluate various surfactants for their beneficial or otherwise effect on applying silicone caulking materials, aqueous solutions of a number of different types of surfactants were prepared in de-ionized water. The surfactants used in this study are listed in Table 1 below along with the suppliers of the surfactants. Table 2 summarizes the surfactant concentrations evaluated, and the observations of the beneficial or otherwise effect of the surfactant solution on the removal of excess silicon caulking material from the ceramic tile and fingers, and the final appearance of the silicone bead.
TABLE 1
Surfactants used in this investigation
Designation
Surfactant Description
of Surfactant
from Supplier
Supplier
Cationic
BTC 824
Stepan Co.
Myristalkonium chloride
Alkyl (60% C 14 , 30% C 16 ,
5% C 12 , 5% C 18 ) dimethyl
benzylammonium chloride
50% Active Liquid
Anionic
Sodium dodecyl sulfate
Fisher Chemical Co.
Non-Ionic
Igepal CO-630, a
Stepan Co.
nonylphenol ethoxylate
Results of Evaluation
Surfactant solutions of 0.1%, 0.3% and 1.0% by weight of as received surfactant in de-ionized water were prepared. Three different surfactants, as outlined in Table 1, were used. The resulting nine solutions were evaluated for their beneficial effect on the application of silicone caulking on the three different surfaces described above. The results of these examinations are summarized Table 2 below.
TABLE 2
Results of Evaluation of Beneficial Effect of Surfactants on
the Application of Silicone Caulking to a Ceramic Surface
Concen-
Surfactant
tration
Observations
Non-ionic
0.1%
Good performance but not the best. On tape
there was some ‘feathering’ and residue of the
silicone caulking. On the finger, some
difficulty was experience in the removal of
excess silicone caulking.
Non-ionic
0.3%
Very good performance on all three surfaces.
Comes off the finger easily. Excess silicone
caulking is easily removed from the tile
surface.
Non-ionic
1.0%
Excellent performance on all three surfaces:
tape, smooth ceramic and rough ceramic.
Excess silicone caulking was easily removed
from the finger and from the surface of tile
using a paper towel. The resulting silicone
caulking bead was judged to have a uniform
appearance with an excellent cosmetic
appearance.
It was agreed by all that the performance of
this surfactant mixture left little if anything to
be desired. Very smooth application.
Cationic
0.1%
Silicone ends to smear on the tile surface.
Poor performance compared to other
mixtures.
Cationic
0.3%
May be better than the 1% cationic solution
below. Not optimum however.
Cationic
1.0%
Tendency to smear. Doesn't re-work as easily
as some of the others. Not optimum.
Anionic
0.1%
Some feathering on the tile surface. Comes off
finger well. On re-tooling or re-working the
silicone caulking bead, there is a tendency to
smear.
Anionic
0.3%
Works very well but not quite as good as the
1% non-ionic. Seems to stick to the finger
more.
Anionic
1.0%
Excellent performance on all surfaces. Very
similar in performance to the 1% non-ionic
mixture.
SUMMARY AND CONCLUSIONS
Both the non-ionic surfactant and the anionic surfactant were found to have a beneficial effect on the application of the silicone caulking to all three surfaces. The cationic surfactant was found to have the least beneficial effect for the application of silicone caulking of all three surfactants at the concentration range investigated. What this means for a tradesman is that all three types of surfactant will work. The tradesman can mix any commercially available soap or detergent containing a surfactant with water and obtain the benefits of the above described method without worrying as to the particular “type” of surfactant to be used. If purchasing a surfactant from a chemical store, it would appear that a non-ionic or anionic surfactant is to be preferred.
In summation, it is to be understood that virtually any currently available household cleaner, detergent or soap would be suitable for use as the surfactant in accordance with the inventive method discussed above. The surfactant found in the following currently available household cleaners, such as WINDEX™, MR. CLEAN™, LYSOL™, FANTASTIK™, FORMULA 409™, for example, would be suitable for practice of the inventive method. It is to be appreciated that the important aspect of the surfactant is that it be in a flowable or spreadable state, e.g., liquid, gel, paste or some other non-solid form, so that it can be sprayed, dispensed, roller, brushed or otherwise applied to the desired surface, after application of the bead of caulk, and prevent the bead of caulk from adhering to undesired portion(s) of the surface when the excess caulk is wiped from the surface.
While any amount of surfactant has beneficial effects, the optimum concentration for beneficial effects of the non-ionic and anionic surfactants appears to be ˜1% in water. There is only a minor improvement in beneficial effect in going from 0.3% to 1.0% for the non-ionic and anionic surfactant, but a substantial difference in beneficial performance was noted from the corresponding 0.1% solutions. Increasing the amount of surfactant beyond 1% is not believed to sufficiently improve performance to warrant the increase cost.
In this patent document, the word “comprising” is used in its non-limiting sense to mean that items following the word are included, but items not specifically mentioned are not excluded. A reference to an element by the indefinite article “a” does not exclude the possibility that more than one of the element is present, unless the context clearly requires that there be one and only one of the elements.
It will be apparent to one skilled in the art that modifications may be made to the illustrated embodiment without departing from the spirit and scope of the invention as hereinafter defined in the Claims.
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A method of applying a silicone caulking compound. A first step involves applying a bead of silicone caulking compound to a seam or surface. A second step involves spraying a surfactant on the bead of silicone caulking compound. A third step involves wiping excess silicone caulking compound from the surface. The surfactant applied to the surface “lubricates” the surface to prevent adhesion of the silicone caulking compound to the surface when excess material is wiped away, thereby preventing smearing.
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CROSS REFERENCE TO RELATED APPLICATIONS
This application is a divisional application of U.S. patent application Ser. No. 13/205,215, filed on Aug. 8, 2011, which claims the priority to U.S. Provisional Application No. 61/503,863, filed on Jul. 1, 2011. All applications are incorporated herein by reference in their entireties.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to body kit panels or accent panels for automotive vehicles. More particularly, the present invention relates to a body hanger bracket for aligning and attaching a body kit panel or accent panel to an automotive vehicle body panel.
2. Description of Related Art
By way of background, body hanger brackets are commonly used for attaching accent panels; such as front, side, and rear ground effect panels, to the front, side, and rear body panels of a vehicle. Typically, the body hanger bracket includes a pair of fingers for vertically aligning the hanger bracket relative to an upper edge of the vehicle body panel while the hanger bracket is fastened to the vehicle body by rivets, bolts, or the like. The hanger bracket includes an elongated lip spaced laterally from the vehicle body for receiving and supporting an upper edge of the accent panel. The upper edge of the accent panel is supported by the hanger bracket and the lower edge of the accent panel is riveted or bolted to an underside of the vehicle body. Current body hanger brackets, however, do not provide both vertical and horizontal alignment of the hanger bracket along the vehicle body panel for accurate alignment and attachment of the accent panel to the vehicle.
It is desirable, therefore, to provide a body hanger bracket that provides both vertical and horizontal alignment of the hanger bracket along a vehicle body panel for alignment and attachment of an accent panel to a vehicle.
SUMMARY
According to one embodiment of the invention, a body hanger bracket is provided for aligning and attaching an accent panel to a vehicle body panel. The hanger bracket includes selectively detachable first and second alignment tabs. The first alignment tab engages a horizontal indexing feature on the vehicle body panel for aligning the hanger bracket horizontally and the second alignment tab engages a vertical indexing feature on the vehicle body panel for aligning the hanger bracket vertically.
According to another embodiment of the invention, a method of installing a body hanger bracket for an accent panel on a vehicle body panel includes the steps of: locating the body hanger bracket in a horizontal direction by engaging a first alignment tab on the hanger bracket with a horizontal indexing feature on the vehicle body panel; locating the hanger bracket in a vertical direction by engaging a second alignment tab on the hanger bracket with a vertical indexing feature on the vehicle body panel; permanently attaching the hanger bracket to the vehicle body panel; and supporting the accent panel on the hanger bracket.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein:
FIG. 1 is a perspective view of a body hanger bracket on a vehicle body panel according to one embodiment of the invention;
FIG. 2 is a cross-sectional view of the body hanger bracket taken through lines 2 - 2 in FIG. 1 ;
FIG. 3 is a cross-sectional view of the body hanger bracket supporting an accent panel;
FIG. 4 is a fragmentary perspective view of the body hanger bracket illustrating a first alignment tab of the body hanger bracket; and
FIG. 5 is a fragmentary perspective view of the body hanger bracket illustrating a second alignment tab of the body hanger bracket.
DETAILED DESCRIPTION OF THE EMBODIMENTS
Referring to FIG. 1 , a vehicle body panel on a vehicle is generally shown at 10 including a front panel 12 , a lateral edge 14 , and a bottom edge 16 . A body hanger bracket, shown at 20 , provides for vertical and horizontal alignment and attachment of the hanger bracket 20 along the front panel 12 of the body panel 10 relative to the lateral edge 14 and the bottom edge 16 . Specifically, the body hanger bracket 20 includes an elongated support plate 22 extending longitudinally between a first alignment tab 24 and an opposite distal end 26 . A plurality of second alignment tabs 28 is spaced apart and extends transversely from the support plate 22 to a hooked distal end 30 . An elongated support lip 32 extends upwardly from a top edge of the support plate 22 and is arranged to be spaced laterally from the front panel 12 defining a channel 33 therebetween. The support lip 32 is adapted for supporting an accent panel 40 as is described below in more detail. In the embodiment shown, the second alignment tabs 28 extend downwardly from a bottom edge of the support plate 22 , however, it is appreciated that the tabs 28 may extend upwardly from a top edge of the support plate 22 without varying from the scope of the invention.
The body hanger bracket 20 is aligned along the vehicle body panel 10 by engaging the first alignment tab 24 with the lateral edge 14 and the second alignment tabs 28 with the bottom edge 16 . It is appreciated that the first and second alignment tabs 24 , 28 may also be aligned with any suitable horizontal and vertical indexing feature on the vehicle body panel 10 , such as vehicle body panel joint lines, sill plates, etc., without varying from the scope of the invention. Once the first and second alignment tabs 24 , 28 are aligned with the respective lateral and bottom edges 14 , 16 , the support plate 22 is temporarily secured to the front panel 12 of the body panel 10 by strips of double-sided adhesive tape 34 , as shown in FIG. 2 . An installer may then drill holes in the body panel 10 through existing holes 35 in the support plate 22 . The body hanger bracket 20 is permanently attached to the body panel 10 by securing the support plate 22 to the body panel 10 with rivets, screws, or the like extending through the existing holes 35 into the holes drilled in the body panel 10 .
The first alignment tab 24 is attached to the support plate 22 by a V-shaped notched membrane 36 to allow the tab 24 to be removed from the support plate 22 after permanent attachment of the body hanger bracket 20 to the body panel 10 . The first alignment tab 24 is removed by bending the tab 24 away from the front panel 12 until the notched membrane 36 breaks. Similarly, the second alignment tabs 28 are attached to the support plate 22 by the V-shaped notched membrane 36 to allow the tabs 28 to be removed from the support plate 22 after permanent attachment of the body hanger bracket 20 to the body panel 10 . The second alignment tabs 28 are removed by bending the tabs 28 away from the front panel 12 until the notched membrane 36 breaks. Additional body hanger brackets may be aligned and attached to the body panel 10 along the length of the vehicle depending on the length and contour of the body panel 10 and associated accent panel 40 .
After the body hanger bracket 20 is aligned and attached to the body panel 10 , and the first and second alignment tabs 24 , 28 are removed; the accent panel 40 is aligned and attached to the body panel 10 . More specifically, referring to FIG. 3 , the accent panel 40 includes an upper hooked portion 42 having longitudinally spaced apart openings 44 in a distal edge thereof. The upper hooked portion 42 is hooked about the support lip 32 on the body hanger bracket 20 to support the accent panel 40 . The support lip 32 includes a plurality of longitudinally spaced apart locking tabs 38 received in the respective openings 44 to secure the accent panel 40 to the body hanger bracket 20 . An opposite lower portion 46 of the accent panel 40 extends adjacent the bottom edge 16 of the vehicle body panel 10 . The accent panel 40 is permanently attached to the bottom edge 16 by securing the lower portion 46 to the bottom edge 16 with rivets, screws, or the like 47 extending through existing holes 48 in the accent panel 40 into holes drilled in the body panel 10 . It is appreciated that the body hanger bracket 20 provides a simple and accurate method of aligning and attaching the accent panel 40 on the body panel 10 within specified tolerances and without expensive tooling or fixtures.
In another embodiment of the invention, one or more of the second alignment tabs 28 includes a drill-hole template 50 extending from the hooked distal end 30 of the respective tab 28 , as shown in FIG. 5 . In the embodiment shown, the drill-hole template 50 includes a semi-circular relief 52 , which is provided as a location guide for an installer to drill a hole in the bottom edge 16 of the vehicle body panel 10 . Thus, when the second alignment tabs 28 are removed and the accent panel 40 is supported on the body hanger bracket 20 , the existing hole 48 in the lower portion 46 of the accent panel 40 will align with the hole drilled in the bottom edge 16 of the body panel 10 for receiving the rivet or screw 47 therethrough. Similarly, the first alignment tab 24 may also include a drill-hole template 54 extending from a distal end thereof, as shown in FIG. 4 . The drill-hole template 54 includes a semi-circular relief 56 , which is provided as a location guide for an installer to drill a hole in the lateral edge 14 of the vehicle body panel 10 . Thus, when the first alignment tab 24 is removed and the accent panel 40 is supported on the body hanger bracket 20 , an existing hole in the accent panel 40 will align with the hole drilled in the lateral edge 14 of the body panel 10 for receiving a rivet or screw therethrough. It is appreciated that the drill-hole templates 50 , 54 may also be a circular hole, slot or other feature that is suitable for use as a location guide without varying from the scope of the invention.
In still another embodiment, a second body hanger bracket, shown at 58 in FIG. 1 , is disposed adjacent to the body hanger bracket 20 . It is appreciated that one end of the second body hanger bracket 58 may abut directly against the distal end 26 of the body hanger bracket 20 to help locate the second body hanger bracket 58 on the vehicle. Alternatively, the second body hanger bracket 58 may be disposed between the body hanger bracket 20 and a remote body hanger bracket, not shown in the Figures. In this case, the second body hanger bracket 58 is centered between the body hanger bracket 20 and the remote body hanger bracket ensuring an even gap between both. The second body hanger bracket 58 may include a removal tab 60 at one or both ends that can be broken off along a notched membrane 62 if additional space is required to center the second body hanger bracket 58 between the body hanger bracket 20 and the remote body hanger bracket.
The invention has been described in an illustrative manner, and it is to be understood that the terminology, which has been used, is intended to be in the nature of words of description rather than of limitation. Many modifications and variations of the present invention are possible in light of the above teachings. It is, therefore, to be understood that within the scope of the appended claims, the invention may be practiced other than as specifically described.
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A body hanger bracket aligns and attaches an accent panel to a vehicle body panel. The hanger bracket includes selectively detachable first and second alignment tabs. The first alignment tab engages a horizontal indexing feature on the vehicle body panel for aligning the hanger bracket horizontally and the second alignment tab engages a vertical indexing feature on the vehicle body panel for aligning the hanger bracket vertically. After the hanger bracket is aligned and attached to the body panel, the first and second alignment tabs are detached. The accent panel is then attached to the hanger bracket.
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CROSS-REFERENCE TO RELATED APPLICATIONS
This application filed Nov. 23, 1999 claims benefit to provisional applications 60/121,730, filed Feb. 26, 1999, and 60/146,564, filed Jul. 30, 1999; and is a Continuation-In-Part from nonprovisional application 09/391,260, filed Sep. 7, 1999 which is a Divisional from nonprovisional application 09/975,573, filed Nov. 21, 1997 now U.S. Pat. No. 6,265,387 issued Nov. 21, 1997, which is a Continuation from 08/571,536, filed Dec. 13, 1995, abandoned.
FIELD OF THE INVENTION
The invention relates to compounds and methods for use in biologic systems. More particularly, processes that transfer nucleic acids into cells are provided. Nucleic acids in the form of naked DNA or a nucleic acid combined with another compound are delivered to cells.
BACKGROUND
Biotechnology includes the delivery of a genetic information to a cell to express an exogenous nucleotide sequence, to inhibit, eliminate, augment, or alter expression of an endogenous nucleotide sequence, or to express a specific physiological characteristic not naturally associated with the cell. Polynucleotides may be coded to express a whole or partial protein, or may be anti-sense.
A basic challenge for biotechnology and thus its subpart, gene therapy, is to develop approaches for delivering genetic information to cells of a patient in a way that is efficient and safe. This problem of “drug delivery,” where the genetic material is a drug, is particularly challenging. If genetic material are appropriately delivered they can potentially enhance a patient's health and, in some instances, lead to a cure. Therefore, a primary focus of gene therapy is based on strategies for delivering genetic material in the form of nucleic acids. After delivery strategies are developed they may be sold commercially since they are then useful for developing drugs.
Delivery of a nucleic acid means to transfer a nucleic acid from a container outside a mammal to near or within the outer cell membrane of a cell in the mammal. The term transfection is used herein, in general, as a substitute for the term delivery, or, more specifically, the transfer of a nucleic acid from directly outside a cell membrane to within the cell membrane. The transferred (or transfected) nucleic acid may contain an expression cassette. If the nucleic acid is a primary RNA transcript that is processed into messenger RNA, a ribosome translates the messenger RNA to produce a protein within the cytoplasm. If the nucleic acid is a DNA, it enters the nucleus where it is transcribed into a messenger RNA that is transported into the cytoplasm where it is translated into a protein. Therefore if a nucleic acid expresses its cognate protein, then it must have entered a cell. A protein may subsequently be degraded into peptides, which may be presented to the immune system.
It was first observed that the in vivo injection of plasmid DNA into muscle enabled the expression of foreign genes in the muscle (Wolff, J A, Malone, R W, Williams, P, et al. Direct gene transfer into mouse muscle in vivo. Science 1990;247:1465-1468.). Since that report, several other studies have reported the ability for foreign gene expression following the direct injection of DNA into the parenchyma of other tissues. Naked DNA was expressed following its injection into cardiac muscle (Acsadi, G., Jiao, S., Jani, A., Duke, D., Williams, P., Chong, W., Wolff, J. A. Direct gene transfer and expression into rat heart in vivo. The New Biologist 3(1), 71-81, 1991.).
SUMMARY
In one preferred embodiment, a process is described for delivering a polynucleotide into a parenchymal cell of a mammal, comprising making a polynucleotide such as a nucleic acid. Then, inserting the polynucleotide into a mammalian vessel, such as a blood vessel and increasing the permeability of the vessel. Finally, delivering the polynucleotide to the parenchymal cell thereby altering endogenous properties of the cell. Increasing the permeability of the vessel consists of increasing pressure against vessel walls. Increasing the pressure consists of increasing a volume of fluid within the vessel. Increasing the volume consists of inserting the polynucleotide in a solution into the vessel wherein the solution contains a compound which complexes with the polynucleotide. A specific volume of the solution is inserted within a specific time period. Increased pressure is controlled by altering the specific volume of the solution in relation to the specific time period of insertion. The vessel may consist of a tail vein. The parenchymal cell is a cell selected from the group consisting of liver cells, spleen cells, heart cells, kidney cells and lung cells.
In another embodiment, a process is described for delivering a polynucleotide complexed with a compound into a parenchymal cell of a mammal, comprising making the polynucleotide-compound complex wherein the compound is selected from the group consisting of amphipathic compounds, polymers and non-viral vectors. Inserting the polynucleotide into a mammalian vessel and increasing the permeability of the vessel. Then, delivering the polynucleotide to the parenchymal cell thereby altering endogenous properties of the cell.
In yet another embodiment, a process is described for transfecting genetic material into a mammalian cell, comprising designing the genetic material for transfection. Inserting the genetic material into a mammalian blood vessel. Increasing permeability of the blood vessel and delivering the genetic material to the parenchymal cell for the purpose of altering endogenous properties of the cell.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates high level luciferase expression in liver following tail vein injections.
FIG. 2 indicates high level luciferase expression in spleen, lung, heart and kidney following tail vein injections.
FIG. 3 illustrates Tail vein injection of pCILuc/polycation complexes in 2.5 ml ringers solution into 25 gram mice.
DETAILED DESCRIPTION
We have found that an intravascular route of administration allows a polynucleotide to be delivered to a parenchymal cell in a more even distribution than direct parenchymal injections. The efficiency of polynucleotide delivery and expression is increased by increasing the permeability of the tissue's blood vessel. Permeability is increased by increasing the intravascular hydrostatic (physical) pressure, delivering the injection fluid rapidly (injecting the injection fluid rapidly), using a large injection volume, and increasing permeability of the vessel wall. Expression of a foreign DNA is obtained in large number of mammalian organs including; liver, spleen, lung, kidney and heart by injecting the naked polynucleotide. Increased expression occurs when polynucleotide is mixed with another compound.
In a first embodiment the compound consists of an amphipathic compound. Amphipathic compounds have both hydrophilic (water-soluble) and hydrophobic (water-insoluble) parts. The amphipathic compound can be cationic or incorporated into a liposome that is positively-charged (cationic) or non-cationic which means neutral, or negatively-charged (anionic). In another embodiment the compound consists of a polymer. In yet another embodiment the compound consists of a non-viral vector. In one embodiment, the compound does not aid the transfection process in vitro of cells in culture but does aid the delivery process in vivo in the whole organism. We also show that foreign gene expression can be achieved in hepatocytes following the rapid injection of naked plasmid DNA in a large volume of physiologic solutions.
The term intravascular refers to an intravascular route of administration that enables a polymer, oligonucleotide, or polynucleotide to be delivered to cells more evenly distributed than direct injections. Intravascular herein means within an internal tubular structure called a vessel that is connected to a tissue or organ within the body of an animal, including mammals. Within the cavity of the tubular structure, a bodily fluid flows to or from the body part. Examples of bodily fluid include blood, lymphatic fluid, or bile. Examples of vessels include arteries, arterioles, capillaries, venules, sinusoids, veins, lymphatics, and bile ducts. The intravascular route includes delivery through the blood vessels such as an artery or a vein.
Afferent blood vessels of organs are defined as vessels in which blood flows toward the organ or tissue under normal physiologic conditions. Efferent blood vessels are defined as vessels in which blood flows away from the organ or tissue under normal physiologic conditions. In the heart, afferent vessels are known as coronary arteries, while efferent vessels are referred to as coronary veins.
The term naked nucleic acids indicates that the nucleic acids are not associated with a transfection reagent or other delivery vehicle that is required for the nucleic acid to be delivered to a target cell. A transfection reagent is a compound or compounds used in the prior art that mediates nucleic acids entry into cells.
Parenchymal Cells
Parenchymal cells are the distinguishing cells of a gland or organ contained in and supported by the connective tissue framework. The parenchymal cells typically perform a function that is unique to the particular organ. The term “parenchymal” often excludes cells that are common to many organs and tissues such as fibroblasts and endothelial cells within blood vessels.
In a liver organ, the parenchymal cells include hepatocytes, Kupffer cells and the epithelial cells that line the biliary tract and bile ductules. The major constituent of the liver parenchyma are polyhedral hepatocytes (also known as hepatic cells) that presents at least one side to an hepatic sinusoid and opposed sides to a bile canaliculus. Liver cells that are not parenchymal cells include cells within the blood vessels such as the endothelial cells or fibroblast cells. In one preferred embodiment hepatocytes are targeted by injecting the polynucleotide within the tail vein of a rodent such as a mouse.
In striated muscle, the parenchymal cells include myoblasts, satellite cells, myotubules, and myofibers. In cardiac muscle, the parenchymal cells include the myocardium also known as cardiac muscle fibers or cardiac muscle cells and the cells of the impulse connecting system such as those that constitute the sinoatrial node, atrioventricular node, and atrioventricular bundle. In one preferred embodiment striated muscle such as skeletal muscle or cardiac muscle is targeted by injecting the polynucleotide into the blood vessel supplying the tissue. In skeletal muscle an artery is the delivery vessel; in cardiac muscle, an artery or vein is used.
Polymers
A polymer is a molecule built up by repetitive bonding together of smaller units called monomers. In this application the term polymer includes both oligomers which have two to about 80 monomers and polymers having more than 80 monomers. The polymer can be linear, branched network, star, comb, or ladder types of polymer. The polymer can be a homopolymer in which a single monomer is used or can be copolymer in which two or more monomers are used. Types of copolymers include alternating, random, block and graft.
One of our several methods of nucleic acid delivery to cells is the use of nucleic acid-polycations complexes. It was shown that cationic proteins like histones and protamines or synthetic polymers like polylysine, polyarginine, polyomithine, DEAE dextran, polybrene, and polyethylenimine are effective intracellular delivery agents while small polycations like spermine are ineffective.
A polycation is a polymer containing a net positive charge, for example poly-L-lysine hydrobromide. The polycation can contain monomer units that are charge positive, charge neutral, or charge negative, however, the net charge of the polymer must be positive. A polycation also can mean a non-polymeric molecule that contains two or more positive charges. A polyanion is a polymer containing a net negative charge, for example polyglutamic acid. The polyanion can contain monomer units that are charge negative, charge neutral, or charge positive, however, the net charge on the polymer must be negative. A polyanion can also mean a non-polymeric molecule that contains two or more negative charges. The term polyion includes polycation, polyanion, zwitterionic polymers, and neutral polymers. The term zwitterionic refers to the product (salt) of the reaction between an acidic group and a basic group that are part of the same molecule. Salts are ionic compounds that dissociate into cations and anions when dissolved in solution. Salts increase the ionic strength of a solution, and consequently decrease interactions between nucleic acids with other cations.
In one embodiment, polycations are mixed with polynucleotides for intravascular delivery to a cell. Polycations provide the advantage of allowing attachment of DNA to the target cell surface. The polymer forms a cross-bridge between the polyanionic nucleic acids and the polyanionic surfaces of the cells. As a result the main mechanism of DNA translocation to the intracellular space might be non-specific adsorptive endocytosis which may be more effective then liquid endocytosis or receptor-mediated endocytosis. Furthermore, polycations are a very convenient linker for attaching specific receptors to DNA and as result, DNA-polycation complexes can be targeted to specific cell types.
Additionally, polycations protect DNA in complexes against nuclease degradation. This is important for both extra-and intracellular preservation of DNA. The endocytic step in the intracellular uptake of DNA-polycation complexes is suggested by results in which DNA expression is only obtained by incorporating a mild hypertonic lysis step (either glycerol or DMSO). Gene expression is also enabled or increased by preventing endosome acidification with NH 4 CI or chloroquine. Polyethylenimine which facilitates gene expression without additional treatments probably disrupts endosomal function itself. Disruption of endosomal function has also been accomplished by linking the polycation to endosomal-disruptive agents such as fusion peptides or adenoviruses.
Polycations also cause DNA condensation. The volume which one DNA molecule occupies in complex with polycations is drastically lower than the volume of a free DNA molecule. The size of DNA/polymer complex may be important for gene delivery in vivo. In terms of intravenous injection, DNA needs to cross the endothelial barrier and reach the parenchymal cells of interest.
The average diameter of liver fenestrae (holes in the endothelial barrier) is about 100 nm, increases in pressure and/or permeability can increase the size of the fenestrae. The fenestrae size in other organs is usually less. The size of the DNA complexes is also important for the cellular uptake process. DNA complexes should be smaller than 200 nm in at least one dimension. After binding to the target cells the DNA-polycation complex is expected to be taken up by endocytosis.
Polymers may incorporate compounds that increase their utility. These groups can be incorporated into monomers prior to polymer formation or attached to the polymer after its formation. The gene transfer enhancing signal (Signal) is defined in this specification as a molecule that modifies the nucleic acid complex and can direct it to a cell location (such as tissue cells) or location in a cell (such as the nucleus) either in culture or in a whole organism. By modifying the cellular or tissue location of the foreign gene, the expression of the foreign gene can be enhanced.
The gene transfer enhancing signal can be a protein, peptide, lipid, steroid, sugar, carbohydrate, nucleic acid or synthetic compound. The gene transfer enhancing signals enhance cellular binding to receptors, cytoplasmic transport to the nucleus and nuclear entry or release from endosomes or other intracellular vesicles.
Nuclear localizing signals enhance the targeting of the gene into proximity of the nucleus and/or its entry into the nucleus. Such nuclear transport signals can be a protein or a peptide such as the SV40 large T ag NLS or the nucleoplasmin NLS. These nuclear localizing signals interact with a variety of nuclear transport factors such as the NLS receptor (karyopherin alpha) which then interacts with karyopherin beta. The nuclear transport proteins themselves could also function as NLS's since they are targeted to the nuclear pore and nucleus.
Signals that enhance release from intracellular compartments (releasing signals) can cause DNA release from intracellular compartments such as endosomes (early and late), lysosomes, phagosomes, vesicle, endoplasmic reticulum, golgi apparatus, trans golgi network (TGN), and sarcoplasmic reticulum. Release includes movement out of an intracellular compartment into cytoplasm or into an organelle such as the nucleus. Releasing signals include chemicals such as chloroquine, bafilomycin or Brefeldin A1and the ER-retaining signal (KDEL sequence), viral components such as influenza virus hemagglutinin subunit HA-2 peptides and other types of amphipathic peptides.
Cellular receptor signals are any signal that enhances the association of the gene with a cell. This can be accomplished by either increasing the binding of the gene to the cell surface and/or its association with an intracellular compartment, for example: ligands that enhance endocytosis by enhancing binding the cell surface. This includes agents that target to the asialoglycoprotein receptor by using asialoglycoproteins or galactose residues. Other proteins such as insulin, EGF, or transferrin can be used for targeting. Peptides that include the RGD sequence can be used to target many cells. Chemical groups that react with sulfhydryl or disulfide groups on cells can also be used to target many types of cells. Folate and other vitamins can also be used for targeting. Other targeting groups include molecules that interact with membranes such as lipids fatty acids, cholesterol, dansyl compounds, and amphotericin derivatives. In addition viral proteins could be used to bind cells.
Polynucleotides
The term nucleic acid is a term of art that refers to a string of at least two base-sugar-phosphate combinations. (A polynucleotide is distinguished from an oligonucleotide by containing more than 120 monomeric units.) Nucleotides are the monomeric units of nucleic acid polymers. The term includes deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) in the form of an oligonucleotide messenger RNA, anti-sense, plasmid DNA, parts of a plasmid DNA or genetic material derived from a virus. Anti-sense is a polynucleotide that interferes with the function of DNA and/or RNA. The term nucleic acids-refers to a string of at least two base-sugar-phosphate combinations. Natural nucleic acids have a phosphate backbone, artificial nucleic acids may contain other types of backbones, but contain the same bases. Nucleotides are the monomeric units of nucleic acid polymers. The term includes deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). RNA may be in the form of an tRNA (transfer RNA), snRNA (small nuclear RNA), rRNA (ribosomal RNA), mRNA (messenger RNA), anti-sense RNA, and ribozymes. DNA may be in form plasmid DNA, viral DNA, linear DNA, or chromosomal DNA or derivatives of these groups. In addition these forms of DNA and RNA may be single, double, triple, or quadruple stranded. The term also includes PNAs (peptide nucleic acids), phosphorothioates, and other variants of the phosphate backbone of native nucleic acids.
A polynucleotide can be delivered to a cell to express an exogenous nucleotide sequence, to inhibit, eliminate, augment, or alter expression of an endogenous nucleotide sequence, or to express a specific physiological characteristic not naturally associated with the cell. Polynucleotides may be coded to express a whole or partial protein, or may be anti-sense.
A delivered polynucleotide can stay within the cytoplasm or nucleus apart from the endogenous genetic material. Alternatively, the polymer could recombine (become a part of) the endogenous genetic material. For example, DNA can insert into chromosomal DNA by either homologous or non-homologous recombination.
Vectors are polynucleic molecules originating from a virus, a plasmid, or the cell of a higher organism into which another nucleic fragment of appropriate size can be integrated without loss of the vectors capacity for self-replication; vectors typically introduce foreign DNA into host cells, where it can be reproduced. Examples are plasmids, cosmids, and yeast artificial chromosomes; vectors are often recombinant molecules containing DNA sequences from several sources. A vector includes a viral vector: for example, adenovirus; DNA; adenoassociated viral vectors (AAV) which are derived from adenoassociated viruses and are smaller than adenoviruses; and retrovirus (any virus in the family Retroviridae that has RNA as its nucleic acid and uses the enzyme reverse transcriptase to copy its genome into the DNA of the host cell's chromosome; examples include VSV G and retroviruses that contain components of lentivirus including HIV type viruses).
A non-viral vector is defined as a vector that is not assembled-within an eukaryotic cell.
Permeability
In another preferred embodiment, the permeability of the vessel is increased. Efficiency of polynucleotide delivery and expression was increased by increasing the permeability of a blood vessel within the target tissue. Permeability is defined here as the propensity for macromolecules such as polynucleotides to move through vessel walls and enter the extravascular space. One measure of permeability is the rate at which macromolecules move through the vessel wall and out of the vessel. Another measure of permeability is the lack of force that resists the movement of polynucleotides being delivered to leave the intravascular space.
To obstruct, in this specification, is to block or inhibit inflow or outflow of blood in a vessel. Rapid injection may be combined with obstructing the outflow to increase permeability. For example, an afferent vessel supplying an organ is rapidly injected and the efferent vessel draining the tissue is ligated transiently. The efferent vessel (also called the venous outflow or tract) draining outflow from the tissue is also partially or totally clamped for a period of time sufficient to allow delivery of a polynucleotide. In the reverse, an efferent is injected and an afferent vessel is occluded.
In another preferred embodiment, the intravascular pressure of a blood vessel is increased by increasing the osmotic pressure within the blood vessel. Typically, hypertonic solutions containing salts such as NaCl, sugars or polyols such as mannitol are used. Hypertonic means that the osmolarity of the injection solution is greater than physiologic osmolarity. Isotonic means that the osmolarity of the injection solution is the same as the physiological osmolarity (the tonicity or osmotic pressure of the solution is similar to that of blood). Hypertonic solutions have increased tonicity and osmotic pressure similar to the osmotic pressure of blood and cause cells to shrink.
In another preferred embodiment, the permeability of the blood vessel can also be increased by a biologically-active molecule. A biologically-active molecule is a protein or a simple chemical such as papaverine or histamine that increases the permeability of the vessel by causing a change in function, activity, or shape of cells within the vessel wall such as the endothelial or smooth muscle cells. Typically, biologically-active molecules interact with a specific receptor or enzyme or protein within the vascular cell to change the vessel's permeability. Biologically-active molecules include vascular permeability factor (VPF) which is also known as vascular endothelial growth factor (VEGF). Another type of biologically-active molecule can also increase permeability by changing the extracellular connective material. For example, an enzyme could digest the extracellular material and increase the number and size of the holes of the connective material.
In another embodiment a non-viral vector along with a polynucleotide is intravascularly injected in a large injection volume. The injection volume is dependent on the size of the animal to be injected and can be from 1.0 to 3.0 ml or greater for small animals (i.e. tail vein injections into mice). The injection volume for rats can be from 6 to 35 ml or greater. The injection volume for primates can be 70 to 200 ml or greater. The injection volumes in terms of ml/body weight can be 0.03 ml/g to 0.1 ml/g or greater.
The injection volume can also be related to the target tissue. For example, delivery of a non-viral vector with a polynucleotide to a limb can be aided by injecting a volume greater than 5 ml per rat limb or greater than 70 ml for a primate. The injection volumes in terms of ml/limb muscle are usually within the range of 0.6 to 1.8 ml/g of muscle but can be greater. In another example, delivery of a polynucleotide to liver in mice can be aided by injecting the non-viral vector—polynucleotide in an injection volume from 0.6 to 1.8 ml/g of liver or greater. In another preferred embodiment, delivering a polynucleotide—non-viral vector to a limb of a primate (rhesus monkey), the complex can be in an injection volume from 0.6 to 1.8 ml/g of limb muscle or anywhere within this range.
In another embodiment the injection fluid is injected into a vessel rapidly. The speed of the injection is partially dependent on the volume to be injected, the size of the vessel to be injected into, and the size of the animal. In one embodiment the total injection volume (1-3 mls) can be injected from 15 to 5 seconds into the vascular system of mice. In another embodiment the total injection volume (6-35 mls) can be injected into the vascular system of rats from 20 to 7 seconds. In another embodiment the total injection volume (80-200 mls) can be injected into the vascular system of monkeys from 120 seconds or less.
In another embodiment a large injection volume is used and the rate of injection is varied. Injection rates of less than 0.012 ml per gram (animal weight) per second are used in this embodiment. In another embodiment injection rates of less than ml per gram (target tissue weight) per second are used for gene delivery to target organs. In another embodiment injection rates of less than 0.06 ml per gram (target tissue weight) per second are used for gene delivery into limb muscle and other muscles of primates.
Reporter Molecules
There are three types of reporter (marker) gene products that are expressed from reporter genes. The reporter gene/protein systems include:
a) Intracellular gene products such as luciferase, β-galactosidase, or chloramphenicol acetyl transferase. Typically, they are enzymes whose enzymatic activity can be easily measured.
b) Intracellular gene products such as β-galactosidase or green fluorescent protein which identify cells expressing the reporter gene. On the basis of the intensity of cellular staining, these reporter gene products also yield qualitative information concerning the amount of foreign protein produced per cell.
c) Secreted gene products such as growth hormone, factor IX, or alpha1-antitrypsin are useful for determining the amount of a secreted protein that a gene transfer procedure can produce. The reporter gene product can be assayed in a small amount of blood.
We have disclosed gene expression achieved from reporter genes in parenchymal cells. The terms “delivery,” “delivering genetic information,” “therapeutic” and “therapeutic results” are defined in this application as representing levels of genetic products, including reporter (marker) gene products, which indicate a reasonable expectation of genetic expression using similar compounds (nucleic acids), at levels considered sufficient by a person having ordinary skill in the art of delivery and gene therapy. For example: Hemophilia A and B are caused by deficiencies of the X-linked clotting factors VIII and IX, respectively. Their clinical course is greatly influenced by the percentage of normal serum levels of factor VIII or IX:<2%, severe; 2-5%, moderate; and 5-30% mild. This indicates that in severe patients only 2% of the normal level can be considered therapeutic. Levels greater than 6% prevent spontaneous bleeds but not those secondary to surgery or injury. A person having ordinary skill in the art of gene therapy would reasonably anticipate therapeutic levels of expression of a gene specific for a disease based upon sufficient levels of marker gene results. In the Hemophilia example, if marker genes were expressed to yield a protein at a level comparable in volume to 2% of the normal level of factor VIII, it can be reasonably expected that the gene coding for factor VIII would also be expressed at similar levels.
EXAMPLES
Enhanced Delivery of Naked DNA
Enhancement of in vivo Gene Expression by M-methyl-L-arginine (L-NMMA) Following Intravascular Delivery of Naked DNA
Intravascular delivery of pCILuc via the iliac artery of rat following a short pre-treatment with L-NMMA delivery enhancer. A 4 cm long abdominal midline excision was performed in 150-200 g, adult Sprague-Dawley rats anesthesized with 80 mg/mg ketamine and 40 mg/kg xylazine. Microvessel clips were placed on external iliac, caudal epigastric, internal iliac and deferent duct arteries and veins to block both outflow and inflow of the blood to the leg. 3 ml of normal saline with 0.66 mM L-NMMA were injected into the external iliac artery. After 2 min 27 g butterfly needle was inserted into the external iliac artery and 10 ml of DNA solution (50 ug/ml pCILuc) in normal saline was injected within 8-9 sec. Luciferase assays was performed 2 days after injection on limb muscle samples (quadriceps femoris).
Organ Treatment Total Luciferase (Nanograms)
Muscle (quadriceps)+papaverine 9,999
Muscle (quadriceps)+0.66 mM L-NMMA 15,398
Muscle (quadriceps)+papaverine, +0.66 mM L-NMMA 24,829
2) Enhancement of in vivo gene expression by aurintricarboxylic Acid (ATA) delivery enhancer following intravascular delivery of naked DNA.
Intravascular delivery of pCILuc in the absence or presence of aurintricarboxylic acid via tail vein injection into mice. 10 micrograms of pCILuc was diluted to 2.5 ml with Ringers solution and aurintricarboxylic acid was added to a final concentration of 0.1 mg/ml. The DNA solution was injected into the tail vein of 25 g ICR mice with an injection time of ˜7 seconds. Mice were sacrificed 24 hours after injection and various organs were assayed for luciferase expression.
Organ Treatment Total Relative Light Units per Organ
Liver none 55,300,000,000
Liver+ATA 109,000,000,000
Spleen none 63,200,000
Spleen+ATA 220,000,000
Lung none 100,000,000
Lung+ATA 128,000,000
Heart none 36,700,000
Heart+ATA 32,500,000
Kidney none 15,800,000
Kidney+ATA 82,400,000
DNA/Polymer Delivery
Rapid injection of pDNA/cationic polymer complexes (containing 10 μg of pCILuc; a luciferase expression vector utilizing the human CMV promoter) in 2.5 ml of Ringers solution (147 mM NaCl, 4 mM KCl, 1.13 mM CaCl2) into the tail vein of ICR mice facilitated expression levels higher than comparable injections using naked plasmid DNA (pCILuc). Maximal luciferase expression using the tail vein approach was achieved when the DNA solution was injected within 7 seconds. Luciferase expression was also critically dependent on the total injection volume and high level gene expression in mice was obtained following tail vein injection of polynucleotide/polymer complexes of 1, 1.5, 2, 2.5, and 3 ml total volume. There is a positive correlation between injection volume and gene expression for total injection volumes over 1 ml. For the highest expression efficiencies an injection delivery rate of greater than 0.003 ml per gram (animal weight) per second is likely required. Injection rates of 0.004, 0.006, 0.009, 0.012 ml per gram (animal weight) per second yield successively greater gene expression levels.
FIG. 1 illustrates high level luciferase expression in liver following tail vein injections of naked plasmid DNA and plasmid DNA complexed with labile disulfide containing polycations L-cystine—1,4-bis(3-aminopropyl)piperazine copolymer (M66) and 5,5′-Dithiobis(2-nitrobenzoic acid)-Pentaethylenehexamine Copolymer (M72). The labile polycations were complexed with DNA at a 3:1 wt:wt ratio resulting in a positively charged complex. Complexes were injected into 25 gram ICR mice in a total volume of 2.5 ml of ringers solution.
FIG. 2 indicates high level luciferase expression in spleen, lung, heart and kidney following tail vein injections of naked plasmid DNA and plasmid DNA complexed with labile disulfide containing polycations M66 and M72. The labile polycations were complexed with DNA at a 3:1 wt:wt ratio resulting in a positively charged complex. Complexes were injected into 25 gram ICR mice in a total volume of 2.5 ml of ringers solution.
Luciferase Expression in a Variety of Tissues Following a Single Tail Vein Injection of pCILuc/66 Complexes:
DNA and polymer 66 were mixed at a 1:1.7 wt:wt ratio in water and diluted to 2.5 ml with Ringers solution as described. Complexes were injected into tail vein of 25 g ICR mice within 7 seconds. Mice were sacrificed 24 hours after injection and various organs were assayed for luciferase expression.
Organ Total Relative Light Units
Prostate 637,000
Skin (abdominal wall) 194,000
Testis 589,000
Skeletal Muscle (quadriceps) 35,000
fat (peritoneal cavity) 44,700
bladder 17,000
brain 247,000
pancreas 2,520,000
Directed Intravascular Injection of pCILuc/66 Polymer Complexes Into Dorsal Vein of Penis Results in High Level Gene Expression in the Prostate and Other Localized Tissues:
Complexes were formed as described for example above and injected rapidly into the dorsal vein of the penis (within 7 seconds). For directed delivery to the prostate with increased hydrostatic pressure, clamps were applied to the inferior vena cava and the anastomotic veins just prior to the injection and removed just after the injection (within 5-10 seconds). Mice were sacrificed 24 hours after injection and various organs were assayed for luciferase expression.
Organ Total Relative Light Units Per Organ
Prostate 129,982,450
Testis 4,229,000
fat (around bladder) 730,300
bladder 618,000
Intravascular Tail Vein Injection Into Rat Results in High Level Gene Expression in a Variety of Organs:
100 micrograms of pCILuc was diluted into 30 mls Ringers solution and injected into the tail vein of 480 gram Harlan Sprague Dawley rat. The entire volume was delivered within 15 seconds. 24 hours after injection various organs were harvested and assayed for luciferase expression.
Organ Total Relative Light Units Per Organ
Liver 30,200,000,000
Spleen 14,800,000
Lung 23,600,000
Heart 5,540,000
Kidney 19,700,000
Prostate 3,490,000
Skeletal Muscle (quadriceps) 7,670,000
Cleavable Polymers
A prerequisite for gene expression is that once DNA/cationic polymer complexes have entered a cell the polynucleotide must be able to dissociate from the cationic polymer. This may occur within cytoplasmic vesicles (i.e. endosomes), in the cytoplasm, or the nucleus. We have developed bulk polymers prepared from disulfide bond containing co-monomers and cationic co-monomers to better facilitate this process. These polymers have been shown to condense polynucleotides, and to release the nucleotides after reduction of the disulfide bond. These polymers can be used to effectively complex with DNA and can also protect DNA from DNases during intravascular delivery to the liver and other organs. After internalization into the cells the polymers are reduced to monomers, effectively releasing the DNA, as a result of the stronger reducing conditions (glutathione) found in the cell. Negatively charged polymers can be fashioned in a similar manner, allowing the condensed nucleic acid particle (DNA+polycation) to be “recharged” with a cleavable anionic polymer resulting in a particle with a net negative charge that after reduction of disulfide bonds will release the polynucleic acid. The reduction potential of the disulfide bond in the reducible co-monomer can be adjusted by chemically altering the disulfide bonds environment. This will allow the construction of particles whose release characteristics can be tailored so that the polynucleic acid is released at the proper point in the delivery process.
Cleavable Cationic Polymers
Cationic cleavable polymers are designed such that the reducibility of disulfide bonds, the charge density of polymer, and the functionalization of the final polymer can all be controlled. The disulfide co-monomer can have reactive ends chosen from, but not limited to the following: the disulfide compounds contain reactive groups that can undergo acylation or alkylation reactions. Such reactive groups include isothiocyanate, isocyanate, acyl azide, N-hydroxysuccinimide esters, succinimide esters, sulfonyl chloride, aldehyde, epoxide, carbonate, imidoester, carboxylate, alkylphosphate, arylhalides (e.g. difluoro-dinitrobenzene) or succinic anhydride.
If functional group A (cationic co-monomer) is an amine then B (disulfide containing comonomer) can be (but not restricted to) an isothiocyanate, isocyanate, acyl azide, N-hydroxysuccinimide, sulfonyl chloride, aldehyde (including formaldehyde and glutaraldehyde), epoxide, carbonate, imidoester, carboxylate, or alkylphosphate, arylhalides (difluoro-dinitrobenzene) or succinic anhyride. In other terms when function A is an amine then function B can be acylating or alkylating agent.
If functional group A is a sulfhydryl then functional group B can be (but not restricted to) an iodoacetyl derivative, maleimide, vinyl sulfone, aziridine derivative, acryloyl derivative, fluorobenzene derivatives, or disulfide derivative (such as a pyridyl disulfide or 5-thio-2-nitrobenzoic acid{TNB} derivatives).
If functional group A is carboxylate then functional group B can be (but not restricted to) a diazoacetate or an amine, alcohol, or sulfhydryl in which carbonyldiimidazole or carbodiimide is used.
If functional group A is an hydroxyl then functional group B can be (but not restricted to) an epoxide, oxirane, or an carboxyl group in which carbonyldiimidazole or carbodiimide or N, N′-disuccinimidyl carbonate, or N-hydroxysuccinimidyl chloroformate is used.
If functional group A is an aldehyde or ketone then function B can be (but not restricted to) an hydrazine, hydrazide derivative, amine (to form a Schiff Base that may or may not be reduced by reducing agents such as NaCNBH3).
The polymer is formed by simply mixing the cationic, and disulfide-containing co-monomers under appropriate conditions for reaction. The resulting polymer may be purified by dialysis or size-exclusion chromatography.
The reduction potential of the disulfide bond can be controlled in two ways. Either by altering the reduction potential of the disulfide bond in the disulfide-containing co-monomer, or by altering the chemical environment of the disulfide bond in the bulk polymer through choice the of cationic co-monomer.
The reduction potential of the disulfide bond in the co-monomer can be controlled by synthesizing new cross-linking reagents. Dimethyl 3,3′-dithiobispropionimidate (DTBP) is a commercially available disulfide containing crosslinker from Pierce Chemical Co. This disulfide bond is reduced by dithiothreitol (DTT), but is only slowly reduced, if at all by biological reducing agents such as glutathione. More readily reducible crosslinkers have been synthesized by Mirus. These crosslinking reagents are based on aromatic disulfides such as 5,5′-dithiobis(2-nitrobenzoic acid) and 2,2′-dithiosalicylic acid. The aromatic rings activate the disulfide bond towards reduction through delocalization of the transient negative charge on the sulfur atom during reduction. The nitro groups further activate the compound to reduction through electron withdrawal which also stabilizes the resulting negative charge (FIG. 2 ).
Cleavable disulfide containing co-monomers:
The reduction potential can also be altered by proper choice of cationic co-monomer. For example when DTBP is polymerized along with diaminobutane the disulfide bond is reduced by DTT, but not glutathione. When ethylenediamine is polymerized with DTBP the disulfide bond is now reduced by glutathione. This is apparently due to the proximity of the disulfide bond to the amidine functionality in the bulk polymer.
The charge density of the bulk polymer can be controlled through choice of cationic monomer, or by incorporating positive charge into the disulfide co-monomer. For example spermine a molecule containing 4 amino groups spaced by 3-4-3 methylene groups could be used for the cationic monomer. Because of the spacing of the amino groups they would all bear positive charges in the bulk polymer with the exception of the end primary amino groups that would be derivitized during the polymerization. Another monomer that could be used is N,N′-bis(2-aminoethyl)-1,3-propediamine (AEPD) a molecule containing 4 amino groups spaced by 2-3-2 methylene groups. In this molecule the spacing of the amines would lead to less positive charge at physiological pH, however the molecule would exhibit pH sensitivity, that is bear different net positive charge, at different pH's. A molecule such as tetraethylenepentamine could also be used as the cationic monomer, this molecule consists of 5 amino groups each spaced by two methylene units. This molecule would give the bulk polymer pH sensitivity, due to the spacing of the amino groups as well as charge density, due to the number and spacing of the amino groups. The charge density can also be affected by incorporating positive charge into the disulfide containing monomer, or by using imidate groups as the reactive portions of the disulfide containing monomer as imidates are transformed into amidines upon reaction with amine which retain the positive charge.
The bulk polymer can be designed to allow further functionalization of the polymer by incorporating monomers with protected primary amino groups. These protected primary amines can then be deprotected and used to attach other functionalities such as nuclear localizing signals, endosome disrupting peptides, cell-specific ligands, fluorescent marker molecules, as a site of attachment for further crosslinking of the polymer to itself once it has been complexed with a polynucleic acid, or as a site of attachment for a second anionic layer when a cleavable polymer/polynucleic acid particle is being recharged to an anionic particle. An example of such a molecule is 3,3′-(N′, N″-tert-butoxycarbonyl)-N-(3′-trifluoroacetamidylpropane)-N-methyldipropylammonium bromide (see experimental), this molecule would be incorporated by removing the two BOC protecting groups, incorporating the deprotected monomer into the bulk polymer, followed by deprotection of the trifluoroacetamide protecting group.
Cleavable Anionic Polymers
Cleavable anionic polymers can be designed in much the same manner as the cationic polymers. Short, multi-valent oligopeptides of glutamic or aspartic acid can be synthesized with the carboxy terminus capped with ethylene diamine. This oligo can the be incorporated into a bulk polymer as a co-monomer with any of the amine reactive disulfide containing crosslinkers mentioned previously. A preferred crosslinker would make use of NHS esters as the reactive group to avoid retention of positive charge as occurs with imidates. The cleavable anionic polymers can be used to recharge positively charged particles of condensed polynucleic acids.
Examples of cleavable polymers:
The cleavable anionic polymers can have co-monomers incorporated to allow attachment of cell-specific ligands, endosome disrupting peptides, fluorescent marker molecules, as a site of attachment for further crosslinking of the polymer to itself once it has been complexed with a polynucleic acid, or as a site of attachment for to the initial cationic layer. For example the carboxyl groups on a portion of the anionic co-monomer could be coupled to an aminoalcohol such as 4-hydroxybutylamine. The resulting alcohol containing comonomer can be incorporated into the bulk polymer at any ratio. The alcohol functionalities can then be oxidized to aldehydes, which can be coupled to amine containing ligands etc. in the presence of sodium cyanoborohydride via reductive amination.
Synthesis of Activated Disulfide Containing Co-monomers
Synthesis of 5,5′-dithiobis(2-nitrobenzoate)propionitrile: 5,5′-dithiobis(2-nitrobenzoic acid) [Ellman's reagent] (500 mg,1.26 mmol) was dissolved in 4.0 ml dioxane. Dicylohexylcarbodiimide (540 mg, 2.6 mmol) and 3-hydroxypropionitrile (240 μL, 188 mg, 2.60 mmol) were added. The reaction mixture was stirred overnight at room temperature. The urea precipitate was removed by centrifugation. The dioxane was removed on rotary evaporator. The residue was washed with saturated bicarbonate, water, and brine; and dried over magnesium sulfate. Solvent removal yielded 696 mg yellow/orange foam. The residue was purified using normal phase HPLC (Alltech econosil, 250×22 nm), flow rate=9.0 ml/min, mobile phase=1% ethanol in chloroform, retention time=13 min. Removal of solvent afforded 233 mg (36.8%) product as a yellow oil. TLC (silica: 5% methanol in chloroform; rf=0.51). H 1 NMR ∂ 8.05 (d, 4H), 7.75 (m, 4H), 4.55 (t, 4H), 2.85 (t, 4H).
Synthesis of 5,5′-dithiobis(2-nitrobenzoic acid)dimethyl propionimidate [DTNBP]: (113.5 mg, 0.226 mmol) was dissolved in 500 μL anhydrous chloroform along with anhydrous methanol (20.0 μL, 0.494 mmol). The flask was stoppered with a rubber septum, chilled to 0° C. on an ice bath, and HCl gas produced by mixing sulfuric acid and ammonium chloride was bubbled through the solution for a period of 10 minutes. The flask was then tightly sealed with parafilm and placed in a −20° C. freezer for a period of 48 hours. During this time a yellow oil formed. The oil was washed thoroughly with chloroform and dried under vacuum to yield 137 mg (95.8%) product as a yellow foam.
3,3′-(N′,N″-tert-butoxycarbonyl)-N-methyldipropylamine (1). 3,3′-Diamino-N-methyldipropylamine (0.800 ml, 0.721 g, 5.0 mmol) was dissolved in 5.0 ml 2.2 N sodium hydroxide (11 mmol). To the solution was added Boc anhydride (2.50 ml, 2.38 g, 10.9 mmol) with magnetic stirring. The reaction mixture was allowed to stir at room temperature overnight (approximately 18 hours). The reaction mixture was made basic by adding additional 2.2 N NaOH until all t-butyl carboxylic acid was in solution. The solution was then extracted into chloroform (2×20 ml). The combined chloroform extracts were washed 2×10 ml water and dried over magnesium sulfate. Solvent removal yielded 1.01 g (61.7%) product as a white solid: 1 H-NMR (CDCl 3 ) δ5.35 (bs, 2H), 3.17 (dt, 4H), 2.37 (t, 4H), 2.15 (s, 3H), 1.65 (tt, 4H), 1.45 (s, 18H).
3,3′-(N ,N″-tert-butoxycarbonyl)-N-(3′-trifluoroacetamidylpropane)-N-methyldipropylammonium bromide (13). Compound 1 (100.6 mg, 0.291 mmol) and compound 4 (76.8 mg, 0.328 mmol) were dissolved in 0.150 ml dimethylformamide. The reaction mixture was incubated at 50° C. for 3 days. TLC (reverse phase; acetonitrile: 50 mM ammonium acetate pH 4.0; 3:1) showed 1 major and 2 minor spots none of which corresponded to starting material. Recrystalization attempts were unsuccessful so product was precipitated from ethanol with ether yielding 165.5 mg (98.2%) product and minor impurities as a clear oil: 1 H-NMR (CDCl 3 ) 6 9.12 (bs, 1H), 5.65 (bs, 2H), 3.50 (m, 8H), 3.20 (m, 4H), 3.15 (s, 3H), 2.20 (m, 2H), 200 (m, 4H), 1.45 (s, 18H).
Intravascular Injections of DNA/Polymer Complexes
Synthesis of N,N′-Bis(t-BOC)-L-cystine:
To a solution of L-cystine (1 gm,4.2 mmol, Aldrich Chemical Company) in acetone (10 ml) and water (10 ml) was added 2-(tert-butoxycarbonyloxyimino)-2-phenylacetonitrile (2.5 gm, 10 mmol, Aldrich Chemical Company) and triethylamine (1.4 ml, 10 mmol, Aldrich Chemical Company). The reaction was allowed to stir overnight at room temperature. The water and acetone was then by rotary evaporation resulting in a yellow solid. The diBOC compound was then isolated by flash chromatography on silica gel eluting with ethyl acetate 0.1% acetic acid.
Synthesis of L-cystine—1,4-bis(3-Aminopropyl)piperazine copolymer (M66):
To a solution of N,N′-Bis(t-BOC)-L-cystine (85 mg, 0.15 mmol) in ethyl acetate (20 ml) was added N,N′-dicyclohexylcarbodiimide (108 mg, 0.5 mmol) and N-hyroxysuccinimide (60 mg, 0.5 mmol). After 2 hr, the solution was filtered through a cotton plug and 1,4-bis(3-aminopropyl)piperazine (54 μL, 0.25 mmol) was added. The reaction was allowed to stir at room temperature for 16 h. The ethyl acetate was then removed by rotary evaporation and the resulting solid was dissolved in trifluoroacetic acid (9.5 ml), water (0.5 ml) and triisopropylsilane (0.5 ml). After 2 h, the trifluoroacetic acid was removed by rotary evaporation and the aqueous solution was dialyzed in a 15,000 MW cutoff tubing against water (2×2 l) for 24 h. The solution was then removed from dialysis tubing, filtered through 5 μM nylon syringe filter and then dried by lyophilization to yield 30 mg of polymer.
Injection of plasmid DNA (pCILuc)/L-cystine—1,4-bis(3-aminopropyl)piperazine copolymer (M66) complexes into the iliac artery of rats.
Complex formation—500 ug pDNA (500 ul) was mixed with M66 copolymer at a 1:3 wt:wt ratio in 500 ul saline. Complexes were then diluted in Ringers solution to total volume of 10 mls.
Injections—total volume of 10 mls was injected into the iliac artery of Sprague-Dawley rats (Harlan, Indianapolis, Ind.) in approximately 10 seconds.
Expression—Animals were sacrificed after 1 week and individual muscle groups were removed and assayed for luciferase expression.
Rat hind limb muscle groups.
1) upper leg posterior−6.46×10 8 total Relative Light Units (32 ng luciferase)
2) upper leg anterior−3.58×10 9 total Relative Light Units (183 ng luciferase)
3) upper leg middle−2.63×10 9 total Relative Light Units (134 ng luciferase)
4) lower leg anterior−3.19×10 9 total Relative Light Units (163 ng luciferase)
5) lower leg anterior−1.97×10 9 total Relative Light Units (101 ng luciferase)
These results indicate that high level gene expression in all muscle groups of the leg was facilitated by intravascular delivery of pCILuc/M66 complexes into rat iliac artery.
Synthesis of 5,5′-Dithiobis[succinimidyl(2-nitrobenzoate):
5,5′-dithiobis(2-nitrobenzoic acid) (50.0 mg, 0.126 mmol, Aldrich Chemical Company) and N-hyroxysuccinimide (29.0 mg, 0.252 mmol, Aldrich Chemical Company) were taken up in 1.0 ml dichloromethane. Dicylohexylcarbodiimide (52.0 mg, 0.252 mmol) was added and the reaction mixture was stirred overnight at room temperature. After 16 hr, the reaction mixture was partitioned in EtOAc/H 2 O. The organic layer was washed 2×H 2 O, 1×brine, dried (MgSO 4 ) and concentrated under reduced pressure. The residue was taken up in CH 2 Cl 2 , filtered, and purified by flash column chromatography on silica gel (130×30 mm, EtOAc:CH 2 Cl 2 1:9 eluent) to afford 42 mg (56%) 5,5′-dithiobis[succinimidyl(2-nitrobenzoate)] as a white solid. H 1 NMR (DMSO) a 7.81-7.77 (d, 2H), 7.57-7.26 (m, 4H), 3.69 (s, 8H).
Synthesis of 5,5′-Dithiobis(2-nitrobenzoic acid)-Pentaethylenehexamine Copolymer (M72):
Pentaethylenehexamine (4.2 μL, 0.017 mmol, Aldrich Chemical Company) was taken up in 1.0 ml dichloromethane and HCl (1 ml, 1 M in Et 2 O, Aldrich Chemical Company) was added Et 2 O was added and the resulting HCl salt was collected by filtration. The salt was taken up in 1 ml DMF and 5,5′-dithiobis[succinimidyl(2-nitrobenzoate)] (10 mg, 0.017 mmol) was added. The resulting solution was heated to 80° C. and diisopropylethylamine (12 μL, 0.068 mmol, Aldrich Chemical Company) was added dropwise. After 16 hr, the solution was cooled, diluted with 3 ml H 2 O, and dialyzed in 12,000-14,000 MW cutoff tubing against water (2×2 L) for 24 hr. The solution was then removed from dialysis tubing and dried by lyophilization to yield 5.9 mg (58%) of 5,5′-dithiobis(2-nitrobenzoic acid)-pentaethylenehexamine Copolymer.
Synthesis of 5,5′-Dithiobis(2-Nitrobenzoic Acid)-Tetraethylenepentamine Copolymer (#M57):
Tetraethylenepentamine (3.2 μL, 0.017 mmol, Aldrich Chemical Company) was taken up in 1.0 ml dichloromethane and HCl (1 ml, 1 M in Et 2 O, Aldrich Chemical Company) was added Et 2 O was added and the resulting HCl salt was collected by filtration. The salt was taken up in 1 ml DMF and 5,5′-dithiobis[succinimidyl (2-nitrobenzoate)] (10 mg, 0.017 mmol) was added. The resulting solution was heated to 80° C. and diisopropylethylamine (15 μL, 0.085 mmol, Aldrich Chemical Company) was added dropwise. After 16 hr, the solution was cooled, diluted with 3 ml H 2 O, and dialyzed in 12,000-14,000 MW cutoff tubing against water (2×2 L) for 24 h. The solution was then removed from dialysis tubing and dried by lyophilization to yield 5.8 mg (62%) of 5,5′-dithiobis(2-nitrobenzoic acid)-tetraethylenepentamine copolymer.
Mouse Tail Vein Injections of pDNA (pCI Luc)/5.5′-Dithiobis(2-nitrobenzoic Acid)-Tetraethylenepentamine Copolymer Complexes:
Complexes were prepared as follows:
Complex I: pDNA (pCI Luc, 200 μg) was added to 300 μL DMSO then 2.5 ml Ringers was added.
Complex II: pDNA (pCI Luc, 200 μg) was added to 300 μL DMSO then 5,5′-Dithiobis(2-nitrobenzoic acid)-Tetraethylenepentamine Copolymer (336 μg) was added followed by 2.5 ml Ringers.
High pressure (2.5 ml) tail vein injections of the complex were performed as previously described (Zhang, G., Budker, V., Wolff, J. “High Levels of Foreign Gene Expression in Hepatocytes from Tail Vein Injections of Naked Plasmid DNA”, Human Gene Therapy, July, 1999). Results reported are for liver expression, and are the average of two mice. Luciferase expression was determined as previously reported (Wolff, J. A., Malone, R. W., Williams, P., Chong, W., Acsadi, G., Jani, A., and Felgner, P. L., 1990 “Direct gene transfer into mouse muscle in vivo,” Science 247, 1465-8.) A Lumat LB 9507 (EG&G Berthold, Bad-Wildbad, Germany) luminometer was used.
Results: High pressure injections
Complex I: 25,200,000 Relative Light Units
Complex II: 21,000,000 Relative Light Units
Results indicate that pDNA (pCI Luc)/5,5′-Dithiobis(2-nitrobenzoic acid)-tetraethylenepentamine copolymer complexes are nearly equivalent to pCI Luc DNA itself in high pressure injections. This indicates that the pDNA is being released from the complex and is accessible for transcription.
Synthesis of 5,5′-Dithiobis(2-nitrobenzoic acid)-Tetraethylenepentamine-Tris(2-aminoethyl)amine Copolymer (#M58):
Tetraethylenepentamine (2.3 μL, 0.012 mmol, Aldrich Chemical Company) and tris(2-aminoethyl)amine (0.51 μL, 0.0034 mmol, Aldrich Chemical Company) were taken up in 0.5 ml methanol and HCl (1 ml, 1 M in Et 2 O, Aldrich Chemical Company) was added. Et 2 O was added and the resulting HCl salt was collected by filtration. The salt was taken up in 1 ml DMF and 5,5′-dithiobis[succinimidyl (2-nitrobenzoate)] (10 mg, 0.017 mmol) was added. The resulting solution was heated to 80° C. and diisopropylethylamine (15 μL, 0.085 mmol, Aldrich Chemical Company) was added dropwise. After 16 hr, the solution was cooled, diluted with 3 ml H 2 O, and dialyzed in 12,000-14,000 MW cutoff tubing against water (2×2 L) for 24 h. The solution was then removed from dialysis tubing and dried by lyophilization to yield 6.9 mg (77%) of 5,5′-dithiobis(2-nitrobenzoic acid)-tetraethylenepentamine-tris(2-aminoethyl)amine copolymer.
Mouse Tail Vein Injections of pDNA (pCI Luc)/5,5′-Dithiobis(2-nitrobenzoic acid)-Tetraethylenepentamine-Tris(2-aminoethyl)amine Copolymer Complexes:
Complexes were prepared as follows:
Complex I: pDNA (pCI Luc, 200 μg) was added to 300 μL DMSO then 2.5 ml Ringers was added.
Complex II: pDNA (pCI Luc, 200 μg) was added to 300 μL DMSO then 5,5′-Dithiobis(2-nitrobenzoic acid)-Tetraethylenepentamine-Tris(2-aminoethyl)amine Copolymer (324 μg) was added followed by 2.5 ml Ringers.
High pressure (2.5 ml) tail vein injections of the complex were performed as previously described. Results reported are for liver expression, and are the average of two mice. Luciferase expression was determined a previously shown.
Results: High pressure Injections
Complex I: 25,200,000 Relative Light Units
Complex II: 37,200,000 Relative Light Units
Results indicate that pDNA (pCI Luc)/5,5′-Dithiobis(2-nitrobenzoic acid)-tetraethylenepentamine-Tris(2-aminoethyl)amine Copolymer Complexes are more effective than pCI Luc DNA in high pressure injections. This indicates that the pDNA is being released from the complex and is accessible for transcription.
Synthesis of 5,5′-Dithiobis(2-nitrobenzoic Acid)—N,N′-Bis(2-aminoethyl)-1,3-propanediamine Copolymer (#M59):
N,N′-Bis(2-aminoethyl)-1,3-propanediamine (2.8 μL, 0.017 mmol, Aldrich Chemical Company) was taken up in 1.0 ml dichloromethane and HCl (1 ml, 1 M in Et 2 O, Aldrich Chemical Company) was added. Et 2 O was added and the resulting HCl salt was collected by filtration. The salt was taken up in 1 ml DMF and 5,5′-dithiobis[succinimidyl(2-nitrobenzoate)] (10 mg, 0.017 mmol) was added. The resulting solution was heated to 80° C. and diisopropylethylamine (12 μL, 0.068 mmol, Aldrich Chemical Company) was added dropwise. After 16 hr, the solution was cooled, diluted with 3 ml H 2 O, and dialyzed in 12,000-14,000 MW cutoff tubing against water (2×2 L) for 24 hr. The solution was then removed from dialysis tubing and dried by lyophilization to yield 5.9 mg (66%) of 5,5′-dithiobis(2-nitrobenzoic acid)-N,N′-bis(2-aminoethyl)-1,3-propanediamine Copolymer.
Mouse Tail Vein Injections of pDNA (pCI Luc)/5,5′-Dithiobis(2-nitrobenzoic acid)—N,N′-Bis(2-aminoethyl)-1,3-propanediamine Copolymer Complexes:
Complexes were prepared as follows:
Complex I: pDNA (pCI Luc, 200 μg) was added to 300 μL DMSO then 2.5 ml Ringers was added.
Complex II: pDNA (pCI Luc, 200 μg) was added to 300 μL DMSO then 5,5′-Dithiobis(2-nitrobenzoic acid)-N,N′-Bis(2-aminoethyl)-1,3-propanediamine Copolymer (474 μg) was added followed by 2.5 ml Ringers.
High pressure tail vein injections of 2.5 ml of the complex were performed as previously described. Results reported are for liver expression, and are the average of two mice. Luciferase expression was determined as previously shown.
Results: High pressure injections
Complex I: 25,200,000 Relative Light Units
Complex II: 341,000 Relative Light Units
Results indicate that pDNA (pCI Luc)/5,5′-Dithiobis(2-nitrobenzoic acid)-tetraethylenepentamine Copolymer Complexes are less effective than pCI Luc DNA in high pressure injections. Although the complex was less effective, the luciferase expression indicates that the pDNA is being released from the complex and is accessible for transcription.
Synthesis of 5,5′-Dithiobis(2-nitrobenzoic acid)—N,N′-Bis(2-aminoethyl)-1,3-propanediamine-Tris(2-aminoethyl)amine Copolymer (#M60):
N,N′-Bis(2-aminoethyl)-1,3-propanediamine (2.0 μL, 0.012 mmol, Aldrich Chemical Company) and tris(2-aminoethyl)amine (0.51 μL, 0.0034 mmol, Aldrich Chemical Company) were taken up in 0.5 ml methanol and HCl (1 ml, 1 M in Et 2 O, Aldrich Chemical Company) was added. Et 2 O was added and the resulting HCl salt was collected by filtration. The salt was taken up in 1 ml DMF and 5,5′-dithiobis[succinimidyl(2-nitrobenzoate)] (10 mg, 0.017 mmol) was added. The resulting solution was heated to 80° C. and diisopropylethylamine (12 μL, 0.068 mmol, Aldrich Chemical Company) was added dropwise. After 16 hr, the solution was cooled, diluted with 3 ml H 2 O, and dialyzed in 12,000-14,000 MW cutoff tubing against water (2×2 L) for 24 hr. The solution was then removed from dialysis tubing and dried by lyophilization to yield 6.0 mg (70%) of 5,5′-dithiobis(2-nitrobenzoic acid)-N,N′-bis(2-aminoethyl)-1,3-propanediamine-tris(2-aminoethyl)amine copolymer.
Mouse Tail Vein Injections of pDNA (pCI Luc)/5,5′-Dithiobis(2-nitrobenzoic acid)-N,N′-Bis(2-aminoethyl)-1,3-propanediamine-Tris(2-aminoethyl)amine Copolymer Complexes:
Complexes were prepared as follows:
Complex I: pDNA (pCI Luc, 200 μg) was added to 300 μL DMSO then 2.5 ml Ringers was added.
Complex II: pDNA (pCI Luc, 200 μg) was added to 300 μL DMSO then 5,5′-Dithiobis(2-nitrobenzoic acid)-N,N′-Bis(2-aminoethyl)-1,3-propanediamine-Tris(2-aminoethyl)amine Copolymer (474 μg) was added followed by 2.5 ml Ringers.
High pressure tail vein injections of 2.5 ml of the complex were preformed as previously described. Results reported are for liver expression, and are the average of two mice. Luciferase expression was determined as previously shown.
Results: High Pressure Injections
Complex I: 25,200,000 Relative Light Units
Complex II: 1,440,000 Relative Light Units
Results indicate that pDNA (pCI Luc)/5,5′-Dithiobis(2-nitrobenzoic acid)-N,N′-Bis(2-aminoethyl)-1,3-propanediamine-Tris(2-aminoethyl)amine Copolymer Complexes are less effective than pCI Luc DNA in high pressure injections. Although the complex was less effective, the luciferase expression indicates that the pDNA is being released from the complex and is accessible for transcription.
Synthesis of Guanidino-L-cystine, 1,4-bis(3-aminopropyl)piperazine Copolymer (#M67):
To a solution of cystine (1 gm, 4.2 mmol) in ammonium hydroxide (10 ml) in a screw-capped vial was added O-methylisourea hydrogen sulfate (1.8 gm, 10 mmol). The vial was sealed and heated to 60° C. for 16 h. The solution was then cooled and the ammonium hydroxide was removed by rotary evaporation. The solid was then dissolved in water (20 ml), filtered through a cotton plug. The product was then isolated by ion exchange chromatography using Bio-Rex 70 resin and eluting with hydrochloric acid (100 mM).
Synthesis of Guanidino-L-cystine 1,4-bis(3-aminopropyl)piperazine Copolymer:
To a solution of guanidino-L-cystine (64 mg, 0.2 mmol) in water (10 ml) was slowly added N,N′-dicyclohexylcarbodiimide (82 mg, 0.4 mmol) and N-hyroxysuccinimide (46 mg, 0.4 mmol) in dioxane (5 ml). After 16 hr, the solution was filtered through a cotton plug and 1,4-bis(3-aminopropyl)piperazine (40 μL, 0.2 mmol) was added. The reaction was allowed to stir at room temperature for 16 h and then the aqueous solution was dialyzed in a 15,000 MW cutoff tubing against water (2×2 l) for 24 h. The solution was then removed from dialysis tubing, filtered through 5 μM nylon syringe filter and then dried by lyophilization to yield 5 mg of polymer.
Particle Size of pDNA-L-cystine—1,4-bis(3-aminopropyl)piperazine Copolymer and DNA-guanidino-L-cystine 1,4-bis(3-aminopropyl)piperazine Copolymer Complexes:
To a solution of pDNA (10 μg/ml) in 0.5 ml 25 mM HEPES buffer pH 7.5 was added 10 μg/ml L-cystine—1,4-bis(3-aminopropyl)piperazine copolymer or guanidino-L-cystine 1,4-bis(3-aminopropyl)piperazine copolymer. The size of the complexes between DNA and the polymers were measured. For both polymers, the size of the particles were approximately 60 nm.
Condensation of DNA With L-cystine—1.4-bis(3-aminopropyl)piperazine Copolymer and Decondensation of DNA Upon Addition of Glutathione:
Fluorescein labeled DNA was used for the determination of DNA condensation in complexes with L-cystine—1,4-bis(3-aminopropyl)piperazine copolymer. pDNA was modified to a level of 1 fluorescein per 100 bases using Mirus' LabelIT Fluorescein kit. The fluorescence was determined using a fluorescence spectrophotometer (Shimadzu RF-1501 spectrofluorometer) at an excitation wavelength of 495 nm and an emission wavelength of 530 nm (Trubetskoy, V. S., Slattum, P. M., Hagstrom, J. E., Wolff, J. A., and Budker, V. G., “Quantitative assessment of DNA condensation,” Anal Biochem 267, 309-13 (1999), incorporated herein by reference).
The intensity of the fluorescence of the fluorescein-labeled DNA (10 μg/ml) in 0.5 ml of 25 mM HEPES buffer pH 7.5 was 300 units. Upon addition of 10 μg/ml of L-cystine—1,4-bis(3-aminopropyl)piperazine copolymer, the intensity decreased to 100 units. To this DNA-polycation sample was added 1 mM glutathione and the intensity of the fluorescence was measured. An increase in intensity was measured to the level observed for the DNA sample alone. The half life of this increase in fluorescence was 8 minutes.
The experiment indicates that DNA complexes with physiologically-labile disulfide-containing polymers are cleavable in the presence of the biological reductant glutathione.
Mouse Tail Vein Injection of DNA-L-cystine—1,4-bis(3-aminopropyl)piperazine Copolymer and DNA-guanidino-L-cystine 1,4-bis(3-aminopropyl)piperazine Copolymer Complexes:
Plasmid delivery in the tail vein of ICR mice was performed as previously described. To pCILuc DNA (50 μg) in 2.5 ml H 2 O was added either L-cystine—1,4-bis(3-aminopropyl)piperazine copolymer, guanidino-L-cystine 1,4-bis(3-aminopropyl)piperazine copolymer, or poly-L-lysine (34,000 MW, Sigma Chemical Company) (50 μg). The samples were then injected into the tail vein of mice using a 30 gauge, 0.5 inch needle. One day after injection, the animal was sacrificed, and a luciferase assay was conducted.
Polycation
ng/liver
poly-L-lysine
6.2
L-cystine- 1,4-bis(3-aminopropyl)piperazine copolymer
439
guanidino-L-cystine 1,4-bis(3-aminopropyl)piperazine
487
copolymer
The experiment indicates that DNA complexes with the physiologically-labile disulfide-containing polymers are capable of being broken, thereby allowing the luciferase gene to be expressed.
Synthesis of 5.5′-Dithiobis(2-nitrobenzoic Acid)-Pentaethylenehexamine Copolymer (#M69):
Pentaethylenehexamine (4.2 μL, 0.017 mmol, Aldrich Chemical Company) was taken up in 1.0 ml dichloromethane and HCl (1 ml, 1 M in Et 2 O, Aldrich Chemical Company) was added Et 2 O was added and the resulting HCl salt was collected by filtration. The salt was taken up in 1 ml DMF and 5,5′-dithiobis[succinimidyl(2-nitrobenzoate)] (10 mg, 0.017 mmol) was added. The resulting solution was heated to 80° C. and diisopropylethylamine (12 μL, 0.068 mmol, Aldrich Chemical Company) was added dropwise. After 16 hr, the solution was cooled, diluted with 3 ml H 2 O, and dialyzed in 12,000-14,000 MW cutoff tubing against water (2×2 L) for 24 hr. The solution was then removed from dialysis tubing and dried by lyophilization to yield 5.9 mg (58%) of 5,5′-dithiobis(2-nitrobenzoic acid)-pentaethylenehexamine Copolymer.
Synthesis of 5,5′-Dithiobis(2-nitrobenzoic acid)-Pentaethylenehexamine-Tris(2-aminoethyl)amine Copolymer (#M70):
Pentaethylenehexamine (2.9 μL, 0.012 mmol, Aldrich Chemical Company) and tris(2-aminoethyl)amine (0.51 μL, 0.0034 mmol, Aldrich Chemical Company) were taken up in 0.5 ml methanol and HCl (1 ml, 1 M in Et 2 O, Aldrich Chemical Company) was added. Et 2 O was added and the resulting HCl salt was collected by filtration. The salt was taken up in 1 ml DMF and 5,5′-dithiobis[succinimidyl(2-nitrobenzoate)] (10 mg, 0.017mmol) was added. The resulting solution was heated to 80° C. and diisopropylethylamine (12 μL, 0.068 mmol, Aldrich Chemical Company) was added dropwise. After 16 hr, the solution was cooled, diluted with 3 ml H 2 O, and dialyzed in 12,000-14,000 MW cutoff tubing against water (2×2 L) for 24 h. The solution was then removed from dialysis tubing and dried by lyophilization to yield. 6.0 mg (64%) of 5,5′-dithiobis(2-nitrobenzoic acid)—pentaethylenehexamine-tris(2-aminoethyl)amine copolymer.
pH Cleavable Polymers for Intracellular Compartment Release
A cellular transport step that has importance for gene transfer and drug delivery is that of release from intracellular compartments such as endosomes (early and late), lysosomes, phagosomes, vesicle, endoplasmic reticulum, golgi apparatus, trans golgi network (TGN), and sarcoplasmic reticulum. Release includes movement out of an intracellular compartment into cytoplasm or into an organelle such as the nucleus. Chemicals such as chloroquine, bafilomycin or Brefeldin A1. Chloroquine decreases the acidification of the endosomal and lysosomal compartments but also affects other cellular functions. Brefeldin A, an isoprenoid fungal metabolite, collapses reversibly the Golgi apparatus into the endoplasmic reticulum and the early endosomal compartment into the trans-Golgi network (TGN) to form tubules. Bafilomycin A 1 , a macrolide antibiotic is a more specific inhibitor of endosomal acidification and vacuolar type H + -ATPase than chloroquine. The ER-retaining signal (KDEL sequence) has been proposed to enhance delivery to the endoplasmic reticulum and prevent delivery to lysosomes.
To increase the stability of DNA particles in serum, we have added to positively-charged DNA-polycation particles polyanions that form a third layer in the DNA complex and make the particle negatively charged. To assist in the disruption of the DNA complexes, we have synthesized polymers that are cleaved in the acid conditions found in the endosome, pH 5-7. We also have reason to believe that cleavage of polymers in the DNA complexes in the endosome assists in endosome disruption and release of DNA into the cytoplasm.
There are two ways to cleave a polyion: cleavage of the polymer backbone resulting in smaller polyions or cleavage of the link between the polymer backbone and the ion resulting in an ion and an polymer. In either case, the interaction between the polyion and DNA is broken and the number of molecules in the endosome increases. This causes an osomotic shock to the endosomes and disrupts the endosomes. In the second case, if the polymer backbone is hydrophobic it may interact with the membrane of the endosome. Either effect may disrupt the endosome and thereby assist in release of DNA.
To construct cleavable polymers, one may attach the ions or polyions together with bonds that are inherently labile such as disulfide bonds, diols, diazo bonds, ester bonds, sulfone bonds, acetals, ketals, enol ethers, enol esters, imines, imminiums, and enamines. Another approach is construct the polymer in such a way as to put reactive groups, i.e. electrophiles and nucleophiles, in close proximity so that reaction between the function groups is rapid. Examples include having carboxylic acid derivatives (acids, esters, amides) and alcohols, thiols, carboxylic acids or amines in the same molecule reacting together to make esters, thiol esters, acid anhydrides or amides.
In one embodiment, ester acids and amide acids that are labile in acidic environments (pH less than 7, greater than 4) to form an alcohol and amine and an anhydride are use in a variety of molecules and polymers that include peptides, lipids, and liposomes.
In one embodiment, ketals that are labile in acidic environments (pH less than 7, greater than 4) to form a diol and a ketone are use in a variety of molecules and polymers that include peptides, lipids, and liposomes.
In one embodiment, acetals that are labile in acidic environments (pH less than 7, greater than 4) to form a diol and an aldehyde are use in a variety of molecules and polymers that include peptides, lipids, and liposomes.
In one embodiment, enols that are labile in acidic environments (pH less than 7, greater than 4) to form a ketone and an alcohol are use in a variety of molecules and polymers that include peptides, lipids, and liposomes.
In one embodiment, iminiums that are labile in acidic environments (pH less than 7, greater than 4) to form an amine and an aldehyde or a ketone are use in a variety of molecules and polymers that include peptides, lipids, and liposomes.
pH-Sensitive Cleavage of Peptides and Polypeptides
In one embodiment, peptides and polypeptides (both referred to as peptides) are modified by an anhydride. The amine (lysine), alcohol (serine, threonine, tyrosine), and thiol (cysteine) groups of the peptides are modified by the an anhydride to produce an amide, ester or thioester acid. In the acidic environment of the internal vesicles (pH less than 6.5, greater than 4.5) (early endosomes, late endosomes, or lysosome) the amide, ester, or thioester is cleaved displaying the original amine, alcohol, or thiol group and the anhydride.
A variety of endosomolytic and amphipathic peptides can be used in this embodiment. A positively-charged amphipathic/endosomolytic peptide is converted to a negatively-charged peptide by reaction with the anhydrides to form the amide acids and this compound is then complexed with a polycation-condensed nucleic acid. After entry into the endosomes, the amide acid is cleaved and the peptide becomes positively charged and is no longer complexed with the polycation-condensed nucleic acid and becomes amphipathic and endosomolytic. In one embodiment the peptides contains tyrosines and lysines. In yet another embodiment, the hydrophobic part of the peptide (after cleavage of the ester acid) is at one end of the peptide and the hydrophilic part (e.g. negatively charged after cleavage) is at another end. The hydrophobic part could be modified with a dimethylmaleic anhydride and the hydrophilic part could be modified with a citranconyl anhydride. Since the dimethylmaleyl group is cleaved more rapidly than the citrconyl group, the hydrophobic part forms first. In another embodiment the hydrophilic part forms alpha helixes or coil-coil structures.
pH-Sensitive Cleavage of Lipids and Liposomes
In another embodiment, the ester, amide or thioester acid is complexed with lipids and liposomes so that in acidic environments the lipids are modified and the liposome becomes disrupted, fusogenic or endosomolytic. The lipid diacylglycerol is reacted with an anhydride to form an ester acid. After acidification in an intracellular vesicle the diacylglycerol reforms and is very lipid bilayer disruptive and fusogenic.
Synthesis of Citraconylpolyvinylphenol
Polyvinylphenol (10 mg 30,000 MW Aldrich Chemical ) was dissolved in 1 ml anhydrous pyridine. To this solution was added citraconic anhydride (100 μL, 1 mmol) and the solution was allowed to react for 16 hr. The solution was then dissolved in 5 ml of aqueous potassium carbonate (100 mM) and dialyzed three times against 2 L water that was at pH8 with addition of potassium carbonate. The solution was then concentrated by lyophilization to 10 mg/ml of citraconylpolyvinylphenol.
Synthesis of Citraconylpoly-L-tyrosine
Poly-L-tyrosine (10 mg, 40,000 MW Sigma Chemical ) was dissolved in 1 ml anhydrous pyridine. To this solution was added citraconic anhydride (100 μL, 1 mmol) and the solution was allowed to react for 16 hr. The solution was then dissolved in 5 ml of aqueous potassium carbonate (100 mM) and dialyzed against 3×2 L water that was at pH8 with addition of potassium carbonate. The solution was then concentrated by lyophilization to 10 mg/ml of citraconylpoly-L-tyrosine.
Synthesis of Citraconylpoly-L-lysine
Poly-L-lysine (10 mg 34,000 MW Sigma Chemical ) was dissolved in 1 ml of aqueous potassium carbonate (100 mM). To this solution was added citraconic anhydride (100 μL, 1 mmol) and the solution was allowed to react for 2 hr. The solution was then dissolved in 5 ml of aqueous potassium carbonate (100 mM) and dialyzed against 3×2 L water that was at pH8 with addition of potassium carbonate. The solution was then concentrated by lyophilization to 10 mg/ml of citraconylpoly-L-lysine.
Synthesis of Dimethylmaleylpoly-L-lysine
Poly-L-lysine (10 mg 34,000 MW Sigma Chemical ) was dissolved in 1 ml of aqueous potassium carbonate (100 mM). To this solution was added 2,3-dimethylmaleic anhydride (100 mg, 1 mmol) and the solution was allowed to react for 2 hr. The solution was then dissolved in 5 ml of aqueous potassium carbonate (100 mM) and dialyzed against 3×2 L water that was at pH8 with addition of potassium carbonate. The solution was then concentrated by lyophilization to 10 mg/ml of dimethylmaleylpoly-L-lysine.
Characterization of Particles Formed With Citraconylated and Dimethylmaleylated Polymers
To a complex of DNA (20 μg/ml) and poly-L-lysine (40 μg/ml) in 1.5 ml was added the various citraconylpolyvinylphenol and citraconylpoly-L-lysine (150 μg/ml). The sizes of the particles formed were measured to be 90-120 nm and the zeta potentials of the particles were measured to be −10 to −30 mV (Brookhaven ZetaPlus Particle Sizer).
To each sample was added acetic acid to make the pH 5. The size of the particles was measured as a function of time. Both citraconylpolyvinylphenol and citraconylpoly-L-lysine DNA complexes were unstable under acid pH. The citraconylpolyvinylphenol sample had particles>1 μm in 5 minutes and citraconylpoly-L-lysine sample had particles>1 μm in 30 minutes.
Synthesis of Glutaric Dialdehyde-Poly-Glutamic Acid (8mer) Copolymer
H 2 N-EEEEEEEE-NHCH 2 CH 2 NH 2 (5.5 mg, 0.0057 mmol, Genosys) was taken up in 0.4 ml H 2 O. Glutaric dialdehyde (0.52 μL, 0.0057 mmol, Aldrich Chemical Company) was added and the mixture was stirred at room temperature. After 10 min the solution was heated to 70° C. After 15 hrs, the solution was cooled to room temperature and dialyzed against H 2 O (2×2L, 3500 MWCO). Lyophilization afforded 4.3 mg (73%) glutaric dialdehyde-poly-glutamic acid (8mer) copolymer.
Synthesis of Ketal from Polyvinylphenyl Ketone and Glycerol
Polyvinyl phenyl ketone (500 mg, 3.78 mmol, Aldrich Chemical Company) was taken up in 20 ml dichloromethane. Glycerol (304 μL, 4.16 mmol, Acros Chemical Company) was added followed by p-toluenesulfonic acid monohydrate (108 mg, 0.57 mmol, Aldrich Chemical Company). Dioxane (10 ml) was added and the solution was stirred at room temperature overnight. After 16 hrs, TLC indicated the presence of ketone. The solution was concentrated under reduced pressure, and the residue redissolved in DMF (7 ml). The solution was heated to 60° C. for 16 hrs. Dialysis against H 2 O (1×3L, 3500 MWCO), followed by Lyophilization resulted in 606 mg (78%) of the ketal.
Synthesis of Ketal Acid of Polyvinylphenyl Ketone and Glycerol Ketal
The ketal from polyvinylphenyl ketone and glycerol (220 mg, 1.07 mmol) was taken up in dichloromethane (5 ml). Succinic anhydride (161 mg, 1.6 mmol, Sigma Chemical Company) was added followed by diisopropylethyl amine (0.37 ml, 2.1 mmol, Aldrich Chemical Company) and the solution was heated at reflux. After 16 hrs, the solution was concentrated, dialyzed against H 2 O (1×3L, 3500 MWCO), and lyophilized to afford 250 mg (75%) of the ketal acid.
Particle Sizing and Acid Lability of Poly-L-Lysine/Ketal Acid of Polyvinylphenyl Ketone and Glycerol Ketal Complexes
Particle sizing (Brookhaven Instruments Corporation, ZetaPlus Particle Sizer, 190, 532 nm) indicated an effective diameter of 172 nm (40 μg) for the ketal acid Addition of acetic acid to a pH of 5 followed by particle sizing indicated a increase in particle size to 84000.
A poly-L-lysine/ketal acid (40 μg, 1:3 charge ratio) sample indicated a particle size of 142 nm. Addition of acetic acid (5 μL, 6 N) followed by mixing and particle sizing indicated an effective diameter of 1970 nm. This solution was heated at 40° C. particle sizing indicated a effective diameter of 74000 and a decrease in particle counts.
Results:
The particle sizer data indicates the loss of particles upon the addition of acetic acid to the mixture.
Synthesis of Ketal from Polyvinyl Alcohol and 4-Acetylbutyric Acid
Polyvinylalcohol (200 mg, 4.54 mmol, 30,000-60,000 MW, Aldrich Chemical Company) was taken up in dioxane (10 ml). 4-acetylbutyric acid (271 μL, 2.27 mmol, Aldrich Chemical Company) was added followed by p-toluenesulfonic acid monohydrate (86 mg, 0.45 mmol, Aldrich Chemical Company). After 16 hrs, TLC indicated the presence of ketone. The solution was concentrated under reduced pressure, and the residue redissolved in DMF (7 ml). The solution was heated to 60° C for 16 hrs. Dialysis against H 2 O (1×4L, 3500 MWCO), followed by lyophilization resulted in 145 mg (32%) of the ketal.
Particle Sizing and Acid Lability of Poly-L-Lysine/Ketal from Polyvinyl Alcohol and 4-Acetylbutyric Acid Complexes
Particle sizing (Brookhaven Instruments Corporation, ZetaPlus Particle Sizer, I90, 532 nm) indicated an effective diameter of 280 nm (743 kcps) for poly-L-lysine/ketal from polyvinyl alcohol and 4-acetylbutyric acid complexes (1:3 charge ratio). A poly-L-lysine sample indicated no particle formation. Similarly, a ketal from polyvinyl alcohol and 4-acetylbutyric acid sample indicated no particle formation. Acetic acid was added to the poly-L-lysine/ketal from polyvinyl alcohol and 4-acetylbutyric acid complexes to a pH of 4.5. Particle sizing indicated particles of 100 nm, but at a minimal count rate (9.2kcps)
Results:
The particle sizer data indicates the loss of particles upon the addition of acetic acid to the mixture.
Synthesis of 1,4-Bis(3-aminopropyl)piperazine Glutaric Dialdehyde Copolymer
1,4-Bis(3-aminopropyl)piperazine (206 μL, 0.998 mmol, Aldrich Chemical Company) was taken up in 5.0 ml H 2 O. Glutaric dialdehyde was (206 μL, 0.998 mmol, Aldrich Chemical Company) was added and the solution was stirred at room temperature. After 30 min, an additional portion of H 2 O was added (20 ml), and the mixture neutralized with 6 N HCl to pH 7, resulting in a red solution. Dialysis against H 2 O (3×3L, 12,000-14,000 MW cutoff tubing) and lyophilization afforded 38 mg (14%) of the copolymer
Particle Sizing and Acid Lability of pDNA (pCI Luc)/1,4-Bis(3-aminopropyl)piperazine Glutaric Dialdehyde Copolymer Complexes (#M140)
To 50 μg pDNA in 2 ml HEPES (25 mM, pH 7.8) was added 135 μg 1,4-bis(3-aminopropyl)piperazine glutaric dialdehyde copolymer. Particle sizing (Brookhaven Instruments Corporation, ZetaPlus Particle Sizer, 190, 532 nm) indicated an effective diameter of 110 nm for the complex. A 50 μg pDNA in 2 ml HEPES (25 mM, pH 7.8) sample indicated no particle formation. Similarly, a 135 μg 1,4-bis(3-aminopropyl)piperazine glutaric dialdehyde copolymer in 2 ml HEPES (25 mM, pH 7.8) sample indicated no particle formation.
Acetic acid was added to the pDNA (pCI Luc)/1,4-bis(3-aminopropyl)piperazine glutaric dialdehyde copolymer complexes to a pH of 4.5. Particle sizing indicated particles of 2888 nm, and aggregation was observed.
Results:
1,4-Bis(3-aminopropyl)piperazine-glutaric dialdehyde copolymer condenses pDNA, forming small particles. Upon acidification, the particle size increases, and aggregation occurs, indicating cleavage of the polymeric immine.
Mouse Tail Vein Injections of pDNA (pCILuc)/1,4-Bis(3-aminopropyl)piperazine Glutaric Dialdehyde Copolymer Complexes
Four complexes were prepared as follows:
Complex I: pDNA (pCI Luc, 50 μg) in 12.5 ml Ringers.
Complex II: pDNA (pCI Luc, 50 μg) was mixed with 1,4-bis(3-aminopropyl)piperazine glutaric dialdehyde copolymer (50 μg) in 1.25 ml HEPES 25 mM, pH 8. This solution was then added to 11.25 ml Ringers.
Complex III: pDNA (pCI Luc, 50 μg) was mixed with poly-L-lysine (94.5 μg, MW 42,000, Sigma Chemical Company) in 12.5 ml Ringers.
2.5 ml tail vein injections of 2.5 ml of the complex were preformed as previously described. Luciferase expression was determined as previously indicated.
Results: 2.5 ml injections
Complex I: 3,692,000 Relative Light Units
Complex II: 1,047,000 Relative Light Units
Complex III: 4,379 Relative Light Units
Results indicate an increased level of pCI Luc DNA expression in pDNA/1,4-bis(3-aminopropyl)piperazine glutaric dialdehyde copolymer complexes over pCI Luc DNA/poly-L-lysine complexes. These results also indicate that the pDNA is being released from the pDNA/1,4-Bis(3-aminopropyl)piperazine-glutaric dialdehyde copolymer complexes, and is accessible for transcription.
Non-cleavable Polymers
Many cationic polymers such as histone (H1, H2a, H2b, H3, H4, H5), HMG proteins, poly-L-lysine, polyethylenimine, protamine, and poly-histidine are used to compact polynucleic acids to help facilitate gene delivery in vitro and in vivo. A key for efficient gene delivery using prior art methods is that the non-cleavable cationic polymers (both in vitro and in vivo) must be present in a charge excess over the DNA so that the overall net charge of the DNA/polycation complex is positive. Conversely, using our tail vein injection process having non-cleavable cationic polymer/DNA complexes we found that gene expression is most efficient when the overall net charge of the complexes are negative (DNA negative charge>polycation positive charge). Tail vein injections using cationic polymers commonly used for DNA condensation and in vitro gene delivery revealed that high gene expression occurred when the net charge of the complexes were negative.
FIG. 3 illustrates tail vein injections of pCILuc/polycation complexes in 2.5 ml ringers solution into 25 gram mice as previously described (Zhang et al. Hum Gen Ther 10: 1735, 1999). The low ratio of each polycation corresponds to wt:wt ratio of 0.5 polycation: 1 DNA (net negative complex). The high ratio of each polycation corresponds to wt:wt ratio of 5 polycation: 1 DNA (net positive complex).
High Efficiency Gene Expression Following Tail Vein Delivery of pDNA/Cationic Peptide Complexes
Plasmid DNA (pCILuc) was mixed with an amphipathic cationic peptide at a 1:2 ratio (charge ratio) and diluted into 2.5 ml of Ringers solution per mouse. Complexes were injected into the tail vein of a 25 g ICR mouse (Harlan Sprague Dawley, Indianapolis, Ind.) in 7 seconds. Animals were sacrificed after 24 hours and livers were removed and assayed for luciferase expression.
Complex Preparation (per mouse)
Complex I: pDNA (pCI Luc, 10 μg) in 2.5 ml Ringers.
Complex II: pDNA (pCI Luc, 10 μg) was mixed with cationic peptide (18 mer KLLKKLLKLWKKLLKKLK) at a 1:2 ratio. Complexes were diluted to 2.5 ml with Ringers solution.
Tail vein injections of 2.5 ml of the complex were preformed as previously described. Luciferase expression was determined as previously shown.
Results: 2.5 ml injections
Complex I: 1.63×10 10 Relative Light Units per liver
Complex II: 2.05×10 10 Relative Light Units per liver
The foregoing is considered as illustrative only of the principles of the invention. Furthermore, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described. Therefore, all suitable modifications and equivalents fall within the scope of the invention.
1
1
18
PRT
Artificial Sequence
Description of Artificial Sequence 18-mer
positive charge
1
Lys Leu Leu Lys Lys Leu Leu Lys Leu Trp Lys Lys Leu Leu Lys Lys
1 5 10 15
Leu Lys
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Disclosed is a process for transfecting genetic material into a mammalian cell to alter endogenous properties of the cell. The process comprises designing a polynucleotide for transfection. Then the polynucleotide is inserted into a mammalian vessel such as a tail vein or artery. Prior to insertion, subsequent to insertion, or concurrent with insertion the permeability of the vessel is increased thereby the genetic material is delivered to the parenchymal cell altering endogenous properties of the cell.
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CROSS-REFERENCE TO RELATED APPLICATIONS
None.
BACKGROUND OF THE INVENTION
This invention relates to lighting systems, and more specifically to systems intended to illuminate motion picture sets and sets of video productions.
The problem of finding the proper illumination for images goes back to the beginning of the visual arts. Long before the advent of photography artists were concerned, even obsessed, with the effect of light on the subjects of their artistic endeavors. Artists traveled over long distances to view the effects of natural light during different times of day, under different cloud conditions, in different latitudes.
During the early days of photography the low sensitivity of early photographic films required a fairly high lighting intensity. In the mid 19th century, OSCAR GUSTAVE REJLANDER, a Swedish painter turned photographer, is said to have used a cat as a primitive exposure meter by placing the cat next to his subject. By looking at the cat's eyes he could tell whether the lighting conditions were proper for photographing his subject.
The first use of artificial light in photography is attributed to L. Ibbetson, who, in 1839, used oxy-hydrogen light when photographing microscopic subjects.
Later photographers used magnesium powder as a source of illumination (flash powder). Magnesium ribbon later replaced powder, and was electrically ignited in flash bulbs. See, for instance, U.S. Pat. No. 3,319,058.
Professional still photography as well as motion picture photography have managed the intensity problem by simply adding more lights to illuminate the subject. Although modern technology has produced light-generating systems with adjustable luminous intensity, the method of adding lights still remains a popular method of controlling both the light intensity, and of illuminating separate parts of the subject differently.
Lighting in connection with photographic images soon became a matter of both intensity and hue. Colors filters became common to further control the appearance of the subject. An example of a motion picture camera with a built-in color conversion filter appears in U.S. Pat. No. 4,033,346.
The present invention incorporates a number of technological improvements into the art of lighting for motion picture and video production. The invention is in the form of an array of lighting modules, electrically interconnected by a wireless network, allowing, at a single location, the adjustment of the light intensity and hue of each module.
The present invention utilizes a single light engine, which contains multiple LEDs in an extremely compact form. This embodiment is much cheaper and easier to manufacture and use than the alternative, that is, the mounting of many individual LEDs.
Furthermore, this invention includes a vastly simplified form of wireless networking: Other lighting systems in the prior art have been networked, but these prior art systems usually involved cables, as well as the requirement for separate addressing of the other systems, and requiring complex protocols, such as DMX®. Other prior art lighting systems have been found which utilize wireless control. However, these prior art systems can be controlled one light at a time, and further require a dedicated remote to control each such light.
Finally, the rotary color adjustment of the present invention brings a new level of convenience and simplicity of operation to the technology. The prior art control systems have all required the management of multiple buttons, in a complex sequence, to attempt to control the lighting hue. Each module has the capability of adjusting both luminous intensity and hue. Despite their technological complexity, the modules are user-friendly, having analog-like concentric control knobs and push button switches.
BRIEF SUMMARY OF THE INVENTION
It is an object of the present invention to provide an array of lighting modules for use in connection with motion picture and video production.
It is a further object of the invention to provide such an array in which each module has a high-intensity light source, with control of luminous intensity and hue.
It is a still further object of the invention to provide such an array which is wirelessly interconnected, so that control of the array may be exercised at a single location.
In accordance with a first aspect of the invention an illumination system suitable for lighting in connection with the production of film or video includes one or more lighting modules, each module having an array of lighting elements as its light source.
In accordance with a second aspect of the invention, the array of lighting elements is embodied as a high-luminous-intensity light engine.
In accordance with a third aspect of the invention the light source is mounted directly to a heat sink.
In accordance with a fourth aspect of the invention a control system capable of adjusting the intensity of light engine is electrically connected to the light source by means of one or more rotary concentric control knobs.
In accordance with a fifth aspect of the invention the control system is further capable of adjusting the hue of the light source that is electrically connected to control circuitry by means of one or more rotary concentric control knobs.
In accordance with a sixth aspect of the invention the control system of each module is interconnected with that of all the other modules by a wireless data network.
In accordance with a seventh aspect of the invention all of the modules are controlled by using the rotary control unit on any individual module.
In accordance with an eighth aspect of the invention the interconnected modules make up a group wherein an additional module may be added to the group by depressing a single pushbutton for a connection period, and then releasing the pushbutton.
In accordance with a ninth aspect of the invention all of the modules of the group are controlled by using the control system of any individual module.
In accordance with a tenth aspect of the invention means are also provided for adjusting the hue of the light produced by the light source.
In accordance with an eleventh aspect of the invention the control system of each module further contain one or more pushbuttons preset to hue parameters of the module.
In accordance with a twelfth aspect of the invention each module provides both a white mode and a color mode.
In accordance with a thirteenth aspect of the invention, when a module is in color mode, a rotary control will allow a user to select every visible combination of red, green, and blue by continually rotating the control in the same direction.
In accordance with a fourteenth aspect of the invention the control system allows the addition of various intensities of white to a selected combination of red, green and blue, thus producing pastel colors.
In accordance with a fifteenth aspect of the invention means are provided to detect the temperature of the light engine, and means are further provided to adjust the light engine's output based on this temperature.
In accordance with a sixteenth aspect of the invention the hue parameters of each pushbutton have a first value when the module is in a white mode, and a second value when the mode is set to color mode.
In accordance with a seventeenth aspect of the invention the control system is separated from the heat sink by a distance of at least 2 cm, to facilitate adequate thermal isolation.
In accordance with an eighteenth aspect of the invention the light engine is approximately 26.7 mm in width by 31.8 mm in height, and the heat sink is approximately 5 cm in width by 5 cm in height.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
These, and further features of the invention, may be better understood with reference to the accompanying specification and drawings depicting the preferred embodiment, in which:
FIG. 1 depicts a front elevation view of the module.
FIG. 2 depicts a perspective view of the module viewed from the front/side.
FIG. 3 depicts a perspective view of the module viewed from the rear/side.
FIG. 4 depicts a cross-sectional view of the module.
FIG. 5 depicts an exploded view of the module, showing the individual components thereof.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
The module which is the basis of the system of the present invention may be understood by first referring to FIGS. 2 and 3 . These figures show a perspective view of the light module from the front and rear corners, respectively. FIG. 2 shows the light engine 3 , mounted on the heat sink 1 by means screws. A light engine connector board 16 , which contains a cutout through which the light engine is seen, is electrically connected to the light engine by solder connections.
The light engine chosen for the preferred embodiment is model BL-3000 manufactured by Lamina Ceramics, Inc., of Westhampton, N.J. The light engine is configured with 39 cavities, shown in the figure as circles. Each of these cavities is populated with multiple LEDs. Light distribution is a 125 degree Lambertian radiation pattern. This unit will deliver 570 lumens in 5500° K white light. The unit chosen for the preferred embodiment is a RGB unit, which provides a full spectrum of different colors.
This light engine is 26.7 mm in width by 31.8 mm in height, and is 2.3 mm thick. The heat sink 3 in which the light engine is mounted is approximately 5 cm square, as viewed from the front, as in FIG. 1 . The thermal interface, having about the same width and height as the light engine 3 , provides for good thermal conductivity between the light engine and the heat sink. The light engine connector board 16 attached to the light engine by solder connections.
The length of the module is about 13 cm, as measured between the face of the small knob 11 to the front of the heat sink 1 . These dimensions demonstrate the compactness of the module, which is of great benefit in ease of handling. It is believed that the prior art does not disclose any modules with the capability of the present invention, while still maintaining the compactness of the present module. The design objectives used in the design of this module established these dimensions within plus or minus ten percent.
The heat sink 1 is seen to consist of a number of fins affixed to a central core 20 . The heat sink is the main structural unit of the module, and it supports the rest of the module. The other components of the module are attached to the rear of the heat sink, and can be best described while viewing FIG. 5 in addition to the previously referenced figures.
With reference to this figure, the control circuitry, for the module, in the form of a control board 7 , is located in an electronic enclosure which is formed from a top enclosure 8 and a bottom enclosure 6 which fit together to enclose the control board. The bottom enclosure 6 has two standoffs integrally formed beneath, which maintains a spacing of approximately 2 cm between the electronics enclosure and the heat sink, and thus thermally isolates the control board from the heat sink. It is believed that a minimum of 2 cm is required to prevent the heat from the light engine from damaging the control circuitry in the after part of the module.
A pair of conduits 5 passes from the electronics enclosure bottom 6 , through the standoffs, and through the heat sink 1 . Electrical connections between the light engine 3 and the control board 7 are made by means of this conduit. In the preferred embodiment, printed circuit boards or printed cables provide the electrical connections between the control board and the light engine.
Still referring to FIG. 5 , it is seen that the shaft of the control board 7 passes through the electronics enclosure top 8 and thus through the intensity control knob 10 and the color control knob 11 . This shaft has two concentric sleeves, one of which mates with each of the knobs. An indicator window 9 allows an indicator light, located on the control board, to be visible through the electronics enclosure top 8 .
Referring next to FIG. 4 , a side cross-sectional view of the module is shown. The different diameters of the shaft of the control board are apparent as the shaft passes through the color control knob 11 and the intensity control knob 10 . The color control knob also acts as a push button control, being spring loaded to return to its normal (out) position when released. This knob acts as a bi-stable control to command the hue to white when other hues were previously in effect.
The distance between the standoffs of the electronics enclosure bottom 6 and the heat sink 1 are clearly visible in this figure.
Several other controls of the module may be seen by referring again to FIG. 2 . Pushbuttons 12 (P 1 ), 13 , and 14 (P 2 ) are seen in this figure, located at the periphery of the electronics enclosure.
Operation of the Controls
As previously stated, the present invention has the capability of adjusting both light intensity and hue, and does so in an extremely user-friendly way.
Intensity is controlled by the larger rotary knob 10 which is rotated clockwise to increase intensity, and is rotated in the anti-clockwise direction to decrease intensity.
Pushing small knob 11 in and holding it there for about one second switches modes between color and white mode. The indicator 9 will glow white when white mode is selected and blue when color mode is selected. Rotating the smaller knob 11 changes the hue continuously as the small knob is rotated while in color mode.
The light engine used in the present invention is the RGB variety. That is, six individual LEDs are located in each of the 39 cavities of the light engine, two of each color. Each color is individually controllable on the light engine. Thus, by controlling the intensity of the Red LED separately from the Blue LED and separately from the Green LED in a particular cavity, each cavity can produce any color desired, at any intensity, within the limits of the LEDs.
The continuous hue control with continuous rotation of the small knob is effected by first having one of the basic colors (Blue, for example) at maximum intensity, and increasing the intensity of the next basic color (Red, for example) while maintaining Blue intensity. In the following example, the small knob is always rotated in the same (clockwise, e.g.) direction.
In this example, as the small knob is first rotated, Red continuously increases, while Blue remains at its maximum intensity. During this step the resulting colors are shades of violet.
After the intensity of Red has reached its maximum, the intensity of Blue begins to decrease until it reaches zero, while the intensity of Red remains constant. Thus, additional shades of violet are produced. After reaching zero, Blue remains at zero until the next cycle. When Blue reaches zero, the light engine is entirely Red. Thereafter, additional rotation of the small knob will result in an increasing intensity of Green from zero while maintaining the intensity of the Red, producing still different shades, etc. When Green reaches maximum intensity, Red is then decreased until reaching zero, while maintaining Green intensity. When Red reaches zero, the light engine is entirely Green.
The process proceeds for an entire cycle, at which time Blue is again introduced, starting at zero intensity, and increases proportionally to the relative rotation of the small knob. Thus, by this implementation, the user may rotate the small knob until the desired color is attained, since all the colors of the spectrum are available as combinations of blue and red, red and green, and green and blue.
Once a desired hue is attained, the user may increase or decrease the intensity without changing the hue by rotating the large knob 10 without moving the small knob 11 .
After selecting the White mode by depressing the small knob 11 , the user may select one of two preset variations of the color white by use of the two pushbuttons 12 and 14 , as may be seen by referring again to FIG. 2 . Pushbutton 12 is preset to 3200° K white, while pushbutton 14 is preset to 5600° K white.
These pushbuttons also function as different presets when in color mode. Setting these pushbuttons to particular hues is a procedure similar to that of setting a preset key to a particular radio station in a car radio. The user first sets the module to the hue desired by using the rotary knobs as previously described, and then presses and holds the desired preset key for over one second. Thereafter, depressing that preset key while in preset mode returns to the hue selected before setting that hue as a preset.
Each module of the present invention contains provisions for wirelessly communicating with other such modules. These modules use a peer-to-peer, master-less network protocol to communicate. This type of network is particularly appropriate for this application because of the simplicity of its architecture and operation. Existing wireless networking components for networks such as ZigBee® are used so that the wireless capability can be easily incorporated in the controller board used herein.
Any number of modules of the present invention may be networked with other of these modules. A network of such modules is called a “group”. A group consists of two or more of these modules.
To establish a two module group, two modules must be in the “on” state. The “on-off” pushbutton 13 also serves as the “link” pushbutton, which adds the present module to other modules in the group.
With a first module in the “on” state, the user pushes the “link” pushbutton 13 on a second module and keeps it depressed for about 3 seconds. The two modules then form a group to which additional modules can be added in the same way as the second module was networked with the first module, as described above.
When a new module is added to the group, the existing modules' output will change to match the color of new module's output, to indicate that the group has been augmented.
When a group of modules has been established, every module in the group will respond to the controls of any module in the group. That is, every module in the group will have the same hue and intensity as every other module.
Referring again to FIG. 2 , a group may be turned off by quickly depressing the “on-off” button. Removing a module from the group is accomplished by disconnecting power from the module. When powered back up again, the module will be independent of the group. A module thus removed from the group may be used independent of the group. Any number of independent modules may be used concurrently with an operating group of modules.
By use of the features just described, it is seen that the modules of the present invention provide flexibility, scalability, ease of use, and a range of intensities and hues not heretofore available. The modules are compact and provide ease of transportation, handling and storage as well.
Examples of additional embodiments of the present invention include, inter alia: using one conduit instead of two to provide electrical connections from light engine to control circuitry; integrating a battery pack within the electronics enclosure; the addition of push buttons for more color and white presets; connecting the light engine to the light engine connector board with plug-in connectors instead of soldering; integration of active or passive heat-tolerant circuitry on light engine connector board; addition of multiple-group capability, while retaining a master-less, peer-to-peer architecture within each group; and integration of optical-feedback circuitry to optically measure and adjust output in addition to temperature feedback.
The use of temperature feedback from the light engine is particularly useful, in that it can be used to maintain the relative intensities of the red, green, and blue lighting elements when the intensity controls are varied. The relative intensities of these colors are referred to herein as “ratiometric” parameters. Thus, the maintaining of these relative intensities are referred to herein as “maintaining ratiometric levels” of the red, green, and blue lighting elements. 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.
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An illumination system suitable for lighting in connection with the production of film or video includes one or more lighting modules, wherein each module contains a light engine, a heat sink to which the light engine is affixed, and a control system electrically connected to the light engine, the control system capable of adjusting both the color and intensity of light engine by means of one or more rotary concentric control knobs and pushbuttons affixed to the control system, and wherein the control systems of each module are interconnected by a wireless data network, so that all of the modules may be controlled by using the rotary control unit on any individual module.
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