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This is a divisional application of U.S. patent application Ser. No. 860,052, filed May 6, 1986, by Kraul et al., entitled "Message Buffer With Improved Escape Sequence and Automatic Document Marking" now abandoned.
TECHNICAL FIELD
This invention relates to digital data equipment and more particularly to message buffers for transferring data between digital data devices.
BACKGROUND OF THE INVENTION
Some digital data devices, such as printers, are considered to be slow speed devices because their limited memory size and the time required to print a character result in a low average data transfer rate. Other digital data devices, such as computers, are considered to be high speed devices because they can send, receive, and process data at a high average rate.
When a high speed device, such as a computer, is connected directly to a low speed device, such as a printer, the computer cannot send a document to the printer as one prolonged data stream at high speed but must send the document as numerous short bursts of data. This prevents the computer from using the part of its memory in which the document resides and also prevents the computer from spending full time on another processing task.
In order to speed up the document transfer and free the computer and its memory to perform other tasks, message buffers, sometimes called "spoolers", were developed. Spoolers generally have a high speed input-only port connected to the computer and a low-speed output-only port connected to the printer, a memory for temporarily storing the document, and a control unit which receives the document at high speed from the computer and writes the document into the memory, and also reads the document from the memory and sends the document at low speed to the printer. This allows the computer to quickly send the entire document and turn to other tasks while the printer prints the document at its more leisurely rate.
However, most spoolers view the entire contents of their memory as long documents. If the user sends two or more documents to the spooler, and then activates the replay feature, all of the documents in the memory will be printed again, even if the user only desired for a reprint of one document.
Some spoolers have a switch or switches so that the user can normally mark the beginning and end of a document. If this is properly done, then activating the replay feature will generally replay only the last document. However, if the user forgets to mark the beginning and end of the document the spooler memory is open and successive documents will be collected in memory as one long document. If the user then activates the replay feature, the entire set of documents will be printed.
There is therefore a need for a message buffer which automatically marks the beginning and end of a document, thereby separating successive documents so that activating the replay feature will cause printing of only the last document.
Also, most spoolers continually reuse the memory so that, at some point, a new document will be written over an older document. However, on occasions, the user may have a document which he wishes to be saved so that he can replay the document at a later time. There is therefore a need for a message buffer which has a provision for saving a document by preventing the memory in which the document is stored from being overwritten by a later document.
In some message buffers, the input and output parameters, such as baud rate, parity, etc., are determined by switches. However, the switches are usually small, generally located on the back of the device or in another inconvenient place, or require a manual to determined the meaning of the switch settings.
There is therefore a need for a message buffer which has command and on-line, or transparent, modes of operation so that the input and output parameters can be controlled by programming signals via an input port. Those skilled in the art will be familiar with command driven modems having both command and on-line modes of operation, such as those shown in U.S. Pat. No. 4,549,302 to Heatherington and U.S. Pat. No. 4,387,440 to Eaton.
Also, there is a need for a message buffer, having a command mode and an on-line mode, to be responsive to a command, through an input port, to change from the on-line mode to the command mode. This command is often called an escape sequence.
However, if the data in a document forms the escape sequence the message buffer will abruptly and unexpectedly switch from the data transfer mode to the command mode. The message buffer will then consider any other information in the document to be a series of valid or invalid commands. At best, the data transfer will be stopped; at worst, the entire contents of the memory will be erased, destroying any documents there, and the operating parameters will be inadvertently changed.
If the input and output parameters of the message buffer are thus inadvertently changed, the data terminal and the message buffer will be attempting to communicate at different speeds, parity, etc. The user will then have to resort to a frustrating trial and error approach of changing the input and output parameters of the data terminal until they match the new, unknown input and output parameters of the message buffer.
There is therefore a need for a message buffer which will automatically change its input and output parameters to a known set of parameters upon receipt of a unique escape command, thereby allowing the data terminal tO easily establish or re-establish communication with the message buffer.
Additionally, a message buffer of the type described in this specification is one species of a multispeed asynchronous data communications device. More particularly, the present invention includes at least one port which normally operates as a port for data communications equipment (DCE) as described in EIA Revised Standard RS-232-C. This port is normally configured to be connected to a data terminal equipment (DTE) output port from a computer or terminal.
The preferred embodiment of the present invention is one for which the DCE port may be operated at a plurality of different data speeds. Since the preferred embodiment is designed to have a command mode and a data transmission (transparent) mode of operation for communications into the above referenced DCE port, it is important that the present invention be configured so that it may be forced into its command mode by the data terminal equipment to which it is attached, irrespective of the data speed at which the data terminal equipment is operating. In the prior art, such an arrangement was not possible unless there was a pre-agreed upon data speed for both the data communications equipment and the data terminal equipment, and both devices were forced to their initial states.
However, the present invention is one in which several functions from the data terminal equipment (normally a computer) will be routed to the DCE input port of the present invention. As the computer changes its mode of operation to route different data to the input port of the present invention, the software controlling the output port of the computer may force this port to operate at different data speeds. Therefore, there is a need to establish a method, and to provide apparatus for executing the method, of operating the DCE input port of a multispeed asynchronous device so that the data terminal equipment to which it is attached can force the DCE into its command mode irrespective of the data speed at which the DTE is operating.
In the prior art, it has been known to use a break sequence provided to data communications equipment to force the equipment into a change of operating state. As will be known to those skilled in the art, a break sequence is executed by establishing a particular logic condition on a data transmission line, for at least a predetermined period of time, when the logic condition differs from the logic condition on the data transmission line when the data terminal equipment is idle (not sending any data).
However, the present invention is one in which the prior art approach is inapplicable. First, as will be apparent from the description of the preferred embodiment to follow, the present invention is one which includes modes of operation for which the device must be transparent to a break condition. In other words, if a break condition is received at the input DCE port, it is necessary under some circumstances to transmit the break condition to an output port of the present invention. The particular example which comes to mind is when the preferred embodiment is in a mode of operation connecting its DCE input port to an output port which is in turn connected to a modem. It is often necessary to send a break sequence on to the modem for transmitting an equivalent modulated sequence to the device with which the modem is communicating.
Secondly, if the user of the computer to which the DCE input port of the present invention is connected has called another program which will communicate with the present invention, the newly called program does not have any way of knowing the data speed of the most recent mode of operation of the input port of the present invention. Thus, there is a need to provide the computer with a dependable scheme for forcing a multispeed data communications device into its command mode of operation, irrespective of its current operational state, particularly with respect to data transmission speed.
SUMMARY OF THE INVENTION
The present invention provides such a message buffer.
Broadly stated, the present invention provides a message buffer which automatically marks the beginning and end of a document and allows the user to save a document for transmittal at a later time.
Also broadly stated, the present invention provides a message buffer which automatically reverts to a predetermined input and output parameter setting upon receipt of a predetermined sequence.
In its preferred form, the present invention automatically defines a document as being the input data between two predetermined periods of no input data.
In its preferred form, the present invention allows the user to designate, after the document has been sent from the computer that the document is to be saved in a replay buffer and not overwritten.
In its preferred form, the present invention allows other documents to be sent to or from the computer and to be sent to the printer even when there is a document stored and saved in the replay buffer.
In its preferred form the present invention also provides for selectably appending additional information to a document which has been stored and saved in the replay buffer.
In its preferred form the present invention has a command mode and an on-line mode so that its operating parameters may be changed by commands via an input port.
In its preferred form the present invention also changes from a data transfer mode to a command mode and reverts to a predetermined set of input/output parameters for a particular port when the break signal into that port from the computer is present for a predetermined period of time and is followed by a predetermined character in accordance with a predetermined set of parameters.
Generally speaking, this aspect of the present invention is usable in any multispeed asynchronous data communications device having both a command mode and a transparent (or data transmission) mode of operation. As stated above in the Background of the Invention section, the fundamental problem is to provide apparatus in the data communications equipment which will always respond to a particular signal sequence as an escape sequence, irrespective of the most recent data speed at which the data communications equipment has been operating. By implementing escape sequence apparatus in the data communications equipment, it is then possible to allow the data terminal equipment to always force the data communications equipment into its command mode of operation irrespective of the previous data speed at which the DCE was operating.
Generally stated, this aspect of the present invention is met by defining the escape sequence of the data communications equipment as provision of a particular non-idle signal condition for a predetermined period of time followed by the provision of a particular character at a predetermined one of the possible data speeds at which the data communications equipment can be operated.
It is preferred that the first condition be met by provision of well known break sequence for a predetermined period of time.
In the preferred embodiment, the escape sequence is further defined by this break sequence being followed by a particular character being transmitted at the highest data speed at which the data terminal equipment can be operated. When these two signals occur contiguously in time, the present invention will be forced into its command mode of operation.
Therefore, any time data terminal equipment, or computer, to which the input port of the present invention is connected needs to force the present invention into its command mode, it need only provide a long break sequence of a predetermined length followed by a provision of a predetermined character at the highest speed of operations (9600 bits per second in the preferred embodiment) and the preferred embodiment will be forced to its command mode.
Naturally, in the preferred embodiment a predetermined data speed for the command mode is initially selected so that the data terminal equipment to which it is attached can provide recognizable commands.
This aspect of the present invention allows the preferred embodiment to be transparent to a break sequence under conditions for which it is needed. It also allows the data terminal equipment to which the present invention is attached to dependably and immediately force data communications equipment embodying the present invention into its command mode without letting the data terminal equipment provide unrecognizable characters resulting in bogus transmission of data to an output port of the present invention.
It is therefore an object of the present invention to provide a message buffer which is responsive to breaks in the data stream for defining the beginning and end of a document.
It is another object of the present invention to provide a message buffer which allows a selected document to be saved and, if desired, appended.
It is another object of the present invention to provide a message buffer which allows a later document to be transferred and printed while an earlier document is still stored and saved.
It is a further object of the present invention to provide a message buffer which is responsive to an escape sequence comprising a break signal in the data input stream followed by a predetermined character.
That the present invention meets these and other objects of the present invention will be apparent from the detailed description below.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a block diagram of the preferred embodiment of the present invention.
FIG. 2A is the first part of a flow chart of the automatic document marking and escape sequences.
FIG. 2B is the second part of a flow chart of the automatic document marking and escape sequences.
DETAILED DESCRIPTION OF THE INVENTION
Turning now to the drawings, in which like numerals reference like components throughout the several figures, the preferred embodiment of the present invention will be described.
FIG. 1 is a block diagram of the preferred embodiment of the present invention. Control unit 10 comprises a microprocessor, multiplexers, clock oscillator, bus logic circuits, and control and decoding circuits. The particular microprocessor used in control unit 10 is not critical but must be fast enough to accommodate the combined data rates of the three ports, A, B, and C.
Read only memory (ROM) 11 comprises a standard ROM and may also comprise an electrically erasable programmable read only memory (EEPROM). The standard ROM section contains the operating instructions for control unit 10 and default settings for the various programmable parameters. The EEPROM section contains user-selected settings for certain of the various programmable parameters. However, in the preferred embodiment, the EEPROM section is separate from the standard ROM and is addressed via PIA 16, discussed below. Methods of programming and operation of ROM 11 are well known to those skilled in the art.
Random access memory (RAM) 12 may be a static or a dynamic RAM. In the preferred embodiment, RAM 12 is a dynamic RAM. RAM 12 must be large enough to accommodate storage of any desired document. In the preferred embodiment, RAM 12 is 128K-by-8 bits and is expandable to 512K-by-8 bits.
DART 13 is a dual universal asynchronous receiver transmitter which, it will be appreciated by one skilled in the art, comprises two universal asynchronous receiver transmitters (UARTs) in a single package sharing common control, address, interrupt and data terminals. One skilled in the art will be familiar with the operation of a dual UART such as DART 13. In the preferred embodiment, DART 13 is a Z8530 serial communications controller (SCC), manufactured by Zilog, Inc., of Campbell, CA. Detailed information on the Z8530 is available from the manufacturer upon request. DART 13 is used to transfer data to and from the two serial input/output ports, B and C.
PIA 16 is a peripheral interface adapter. In the preferred embodiment, PIA 16 is an R6522 manufactured by Rockwell International of Newport Beach, CA. Detailed information on the R6522 device is available from the manufacturer upon request. PIA 16 can be configured to have two eight-bit bidirectional input/output ports PA and PB, an eight-bit bidirectional data port, a serial data port, programmable control and status registers, and two 16-bit programmable timers/counters. PIA 16 is used to transfer data to the output port, A, and is also used to interface with control switches 36, display indicators 37, the real time clock 20, and the EEPROM 41.
Interface circuit 14 comprises line drivers, a multiplexer, and input and output decoupling networks. Interface circuit 14 accepts signals from port C, buffers them, and sends them to the A section of DART 13. Interface circuit 14 also accepts signals from the A section of DART 13, buffers them, and sends them to port C.
Interface circuit 15 performs a similar function as interface circuit 14 but with respect to the B section of DART 13 and port B. Methods of construction of interface circuits 14 and 15 are well known to those skilled in the art.
Switches 36 comprises a set of push-button switches which, for convenience, are called SELECT, MARK, and REPLAY. The SELECT switch 36 allows the user to select one of a set of predetermined data paths, e.g.--port A to port C, port B to port C, port B to ports A and C, etc. Means of programming control unit 10 to sense the SELECT switch 37 and route the data accordingly are well known to those skilled in the art.
Display indicator 37 comprises a set of light emitting diodes, one of which, for convenience, is called the MARK indicator. Display indicator 37 displays the status and may include other indicator 37 such as "POWER", "READY", "PATH SELECTOR", etc. Means of programming control unit 10 to display the status by indicator 37 are well known to those skilled in the art.
Real time clock 20 is a clock timer and, once set, keeps track of the time and the date. In the preferred embodiment, real time clock 20 is an MSM5832RS manufactured by OKI Semiconductor of Sunnyvale, CA. Detailed information on the MSM5832RS is available from the manufacturer upon request. In the preferred embodiment real time clock 20 has a battery backup power supply (not shown) so that the correct time will be maintained even when normal operating power is not available.
In the preferred embodiment, real time clock 20 is read by control unit 10 upon a power up reset, or reset. After that, control unit 10 periodically updates a time of day (TOD) clock register in RAM 12 instead of periodically reading the real time clock 20. This method was chosen simply to save processing time for control unit 10.
Interface circuit 17 comprises a bidirectional eight bit data buffer, input and output buffers, multiplexers, latches, and address and decoding logic. Interface circuit 17 accepts and buffer signals from PIA 16 to port A and from port A to PIA 16. Interface circuit 17 also accepts signals from the switches 36 and provides them to PIA 16. Interface circuit 17 also accepts signals from PIA 16 and control unit 10 and provides latched output signals to the display indicator 37. Interface circuit 17 also routes control signals from PIA 16 and control unit 10 to real time clock 20 and time signals from real time clock 20 to PIA 16. Interface circuit 17 also routes control signals from PIA 16 and control unit 10 to EEPROM 41 and data signals from EEPROM 41 to PIA 16. It will be appreciated that PIA 16 and interface buffer 17, in addition to handling signals to and from port A, provide a means for routing signals to the real time clock 20, EEPROM 41, and the display indicator 37, and signal from the real time clock 20, EEPROM 41, and the switches 36. Means of construction of interface circuit 17 are well known to those skilled in the art.
Port A is a fifteen conductor parallel/serial output port. If port A is connected to a parallel input printer, eight conductors are used for the parallel eight-bit data byte output, one conductor is the negated strobe signal output, one conductor is the negated acknowledge signal input, one conductor is the busy signal input, one conductor is the PE signal input, one conductor is the negated INIT signal output, one conductor is the negated error signal input, and one conductor is the system ground.
If port A is connected to a serial input printer, only six conductors are used. The negated strobe signal conductor is now used for the serial transmit data output. The busy signal input conductor is now used for the data set ready signal input.
Further more, in order to indicate to control unit 10 that the printer connected to port A is a serial printer, the plug (not shown) connecting port A to the printer has two jumpers. One jumper is from the system ground conductor to a first predetermined one of the parallel eight-bit data output conductors. Another jumper is from the negated INIT signal output conductor to a second predetermined one of the parallel eight-bit data output conductor. Control unit 10 places a predetermined data signal on the negated INIT conductor and looks at the signal present on the first one and then second one of the parallel eight-bit output conductors. If the signal on the first one of the parallel eight-bit data output conductors is system ground, and the signal on the second one of the parallel eight-bit data output conductors in the same as the predetermined data signal on the negated INIT conductor, then control unit 10 determines that the printer connected to port A is a serial printer and configures port A accordingly.
The predetermined data signal may be a series of alternating logic 1's and 0's, or any other convenient series. In the preferred embodiment, the first predetermined conductor is the D3 conductor and the second predetermined conductor is the D4 conductor, where D0 is the least significant bit of the parallel eight-bit data output.
Port C is a nine conductor serial input/output port. The nine conductors are: chassis ground, system ground, data carrier detect input, data terminal ready output, data set ready input, transmit data plus and transmit data minus outputs, and receive data plus and receive data minus inputs. The transmit data plus and transmit data minus outputs form a transmit data differential output pair. Likewise, the receive data plus and receive data minus inputs form a receive data differential input pair.
These two differential pairs allow port C in the preferred embodiment to be used with devices which require these differential input and output connections. If the device connected to port C does not require a differential input and output connection, then the receive data plus input is connected to system ground at port C and the transmit data plus input is not used.
Port B is also a nine conductor serial input/output port. The nine conductors are: system ground, data carrier detect input, receive data input, transmit data input, data terminal ready output, data set ready output, ready to send output, clear to send input, and ring indicator input.
In the preferred environment of the preferred embodiment of the present invention, port C is connected to the serial input/output port of a computer and port B is connected to the serial input/output port of a modem.
Control unit 10 is connected by control bus 21, data bus 22, and address bus 23 to ROM 11, RAM 12, DART 13, and PIA 16. Control unit 10 is also connected by control bus 21 and address bus 23 to interface circuit 17. The negated interrupt request outputs of DART 13 and PIA 16 are connected by conductor 24 to the negated interrupt request input of control unit 10. The section A inputs and outputs of DART 13 are connected by a plurality of conductors 25 to the outputs and inputs, respectively, of interface circuit 14. The serial inputs and outputs of interface circuit 14 are connected to serial input/output port C by a plurality of conductors 27. The section B inputs and outputs of DART 13 are connected by a plurality of conductors 26 to the outputs and inputs, respectively, of interface circuit 15. The serial inputs and outputs of interface circuit 15 are connected to said input/output port B by a plurality of conductors 30.
The port A (PA), port B (PB), control A (CA), and control B (CB) inputs and outputs of PIA 16 are connected by a plurality of conductors 31 to the outputs and inputs, respectively, of interface circuit 17. The parallel/serial inputs and outputs of interface circuit 17 are connected to parallel/serial output port A by a plurality of conductors 32. The switch inputs of interface circuit 17 are connected by a plurality of conductors 35 to the outputs of the switches 36. The display outputs of interface circuit 17 are connected by a plurality of conductors 34 to the inputs of the display indicators 37. The clock control and data inputs and outputs of interface circuit 17 are connected by a plurality of conductors 33 to the control and data outputs and inputs, respectively, of real time clock 20. The EEPROM control and data inputs and outputs of interface circuit 17 are connected by a plurality of conductor 40 to the control and data outputs and inputs, respectively, of EEPROM 41.
The operation of the preferred embodiment of the present invention will now be described. The preferred embodiment is configured as a polled system. The polling rate is conveniently chosen as 1200 times per second. PIA 16 is programmed by control unit 10 to generate an interrupt every 1/1200 second. On every interrupt, control unit 10 updates the TOD clock register in RAM 12, refreshes a part of RAM 12, reads any incoming data in DART 13, updates the outgoing handshake signals for ports A, B and C, and, if port A is configured for a serial output, updates, if the printer is ready, the data going to port A. On every other interrupt control unit 10 refreshes the display indicators 37, updates, if permitted, the data going to ports B and C, checks the incoming handshake signals on ports A, B and C, and, if port A is configured for parallel output, updates, if the printer is ready, the data going to port A. Control unit 10 checks the status of switches 36 every sixteen interrupts. Although the negated interrupt request output of DART 13 is connected to control unit 10, this negated interrupt request output is disabled so that PIA 16 is the only source of interrupts for control unit 10. Methods of programming control unit 10 and PIA 16 to accomplish polling at 1200 times per second are well known to those skilled in the art.
Control unit 10 divides RAM 12 into several parts. The two parts of interest are called the replay buffer and the immediate buffer. The particular areas of RAM 12 which are used by these two buffers vary dynamically in size and location depending upon the document or documents stored in RAM 12.
A document stored in the replay buffer may be replayed and may be protected. However, a document in the immediate buffer may neither be replayed nor protected.
The preferred embodiment has two modes: command mode, and on-line mode. However, control unit 10 may be in the command mode with respect to one port, for example, port H, and be in the on-line mode with respect to the other port, port C. It will be recalled that port A is an output-only port and so control unit 10 is always on-line with respect to port A.
When control unit 10 is in the command mode the user may define data transfer paths, e.g., port B to port A, port B to ports A and C, etc., configure the input/output parameter settings, e.g., baud rate, number of bits, parity, etc., and define other desired operating parameters. The use of a command mode and an on-line mode in modems is well known to those skilled in the art and is applicable to the present invention.
Assume now that a computer (not shown) is connected to port B, a printer (not shown) is connected to port A, and that ports A and B are properly configured to operate with the printer and computer, respectively. Also assume that control unit 10 is in the on-line mode with respect to port B.
When the user sends a document from port B, control unit 10 will read the data from DART 13, store the data in RAM 12, and increment the replay buffer input pointer. Control unit 10 will also read the stored data from RAM 12, send it to PIA 16, and increment the replay buffer output pointer. PIA 16 sends the data to the printer via port A. It will be appreciated that data from port B may be read and stored in RAM 12 at different intervals than the data is read from RAM 12 and sent to port A. Means of programming control unit 10 to perform this type of input/output function are well known to those skilled in the art.
If the user presses the REPLAY button 36, control unit 10 will reset the replay buffer output pointer and begin reading from the replay buffer in RAM 12 and sending to the printer via port A another copy of the document.
If the user begins sending a second document within a predetermined period of time, called, for convenience, the spacing time, control unit 10 will consider the second document to be part of the first document, will append it to the end of the first document, and also store the second document in the replay buffer of RAM 12 as part of the first document.
However, assume that the user desires that the second document retain a distinct identity and not be part of the first document. In this case the user will, after the first document has been sent, wait for a period longer than the spacing time before beginning sending the second document. Control unit 10 will consider the longer period to be an indication that the first document has been completed. Control unit 10 will then mark, in RAM 12, the end of the first document and also the beginning of the second document.
As soon as the first document has been printed, control unit 10 will clear any pointers to the first document. Since there are no pointers to the first document it is nOw inaccessible. The first document may therefore be considered to have been erased from RAM 12. The replay buffer will then contain only the second document.
If the user now presses the REPLAY button 36, control unit 10 will reset the replay buffer output pointer to the beginning of the second document and begin reading from the replay buffer in RAM 12 and sending to the printer via port A another copy of the second document.
This happens because the longer period between the first document and the second document causes control unit 10 to distinguish between the two documents and erase the first document from the replay buffer. Therefore, when the user pressed the REPLAY button 36, the only document in the replay buffer in RAM 12 is the second document. This is advantageous over prior art message buffers where pressing the REPLAY button caused the entire contents of the memory to be printed, i.e., every document sent since the last manual erase.
The above description therefore provides a method of using a spacing timer for automatically marking the end of a document, and therefore the beginning of a successor document so that pressing the REPLAY button will normally only cause the last document, rather than all documents, to be printed.
However, assume now that the user had begun sending the first document and was interrupted for some reason for a period longer than the spacing time. Control unit 10 has now automatically marked the end of the first document so if the user begins sending more data control unit 10 will treat the new data as a second document instead of more of the first document.
In the preferred embodiment, in order to remove the mark at the end of the first document the user will press and hold MARK button 36 until MARK indicator 37 begins to blink, and then release MARK button 36. By holding MARK button 36 for this period of time, the user instructs control unit 10 to protect the first document in the replay buffer in RAM 12. Control unit 10 acknowledges the instruction by causing MARK indicator 36 to blink. By this action the user has protected the first document in the replay buffer in RAM 12. Therefore, at this time, no other data can be entered into the replay buffer. The blinking of MARK indicator 37 is merely an acknowledgment of the instruction to the user. It will be appreciated that other methods of acknowledgment may also be used. Means of programming control unit 10 to sense the status of MARK button 36 and cause MARK indicator 37 to blink are well known to those skilled in the art.
If the user now begins sending more data, control unit 10 views this as a separate document and, since the contents of the replay buffer are protected, will store this data in the immediate buffer in RAM 12 and also cause the data in the immediate buffer to be read and sent to the printer. Documents in the immediate buffer cannot be replayed or protected.
However, if, after pressing and holding the MARK button 36, the user again presses the MARK button 36 until the MARK indicator 37 is steadily on, and then releases MARK button 36, control unit 10 will unlock the replay buffer and remove the end mark. Now, any data from the user is appended to the first document and becomes part of the first document. At this point, however, the contents of the replay buffer may be appended, but are otherwise protected, and the spacing time automatic document marking feature is disabled.
It will be appreciated that control unit 10 marks the beginning and end of a document by reading and storing in RAM 12 the starting and final values of the replay buffer input pointer. Control unit 10 also prefixes each document with a header which specifies the port to which the document is to be routed. Means of programming control unit 10 to read and store pointer values are well known to those skilled in the art.
Assume now that, for some reason, the user has changed the input/output parameters of the computer, but not of port B, and desires to reestablish communication through port B.
In practice, this normally occurs as the user of a computer (not shown) attached to port B starts a new applications program which must communicate with the preferred embodiment. The new applications program has no way of knowing the present data speed and other parameter at which port B is operating.
The preferred embodiment also responds to the well known Hayes AT command set escape sequence described in U.S. Pat. No. 4,459,302 to Heatherington. However, for the AT command set escape sequence to operate, both the computer and port B must be operating at the same speed. Thus, unless the new applications program can correctly guess the data speed for port B, the AT command set escape sequence cannot be used. Then, in order to reestablish the command state so that the computer can communicate with control unit 10 the new program will: (1) set the input/output parameters of the computer to 9600 bits/second, 8 data bits/character, no parity bit, and one stop bit; (2) send a break signal for at least a first predetermined amount of time, called the minimum break time, (3) drop the break signal within a second predetermined time of the beginning of the first predetermined time period called the maximum break time, and (4) send a predetermined character within a third predetermined period of time, called the lapse time, of dropping the break signal. In the preferred embodiment, the minimum and maximum break times are conveniently chosen to be 800 and 1500 milliseconds, respectively, and the lapse time is conveniently chosen to be approximately 21 milliseconds.
In the preferred embodiment, the predetermined character is chosen to be the dollar ($) (ASCII 36) character. It will be appreciated that other characters, or combinations of characters, may also be used.
When control unit 10 detects a break signal for a period of about 800 milliseconds then, if the break signal is dropped within the next 700 milliseconds, control unit 10 reprograms the appropriate section of DART 13 for 9600 baud, 8 data bits per character, no parity bit, and one stop bit.
If, after sending the break signal for at least the minimum break time of 800 milliseconds, dropping the break signal before the maximum break time and within the lapse time, the first character sent by the computer is the $ character, at the parameters specified above, control unit 10 goes into the command mode. Thereafter, the user can communicate with control unit 10 at the parameters specified above and can, for example, command control unit 10 to change to another set of input/output parameters, execute other commands, or return to the on-line mode.
If, after the break signal is present for at least the minimum break time, the first character sent by the computer is not the $ character, or is a character sent at other than the 9600 baud, 8 data bits, no parity bit, one stop bit, parameters, then control unit 10 will reprogram section B of DART 13 back to the previous input/output parameters. In the preferred embodiment, no attempt is made to reconstruct the character so this first character will be lost. It will be appreciated that, if desired, control unit 10 can be programmed to reconstruct this first character. Also, if no character is sent within the lapse time, or by the end of the 1500 millisecond maximum break time, the break signal is not dropped, control unit 10 will reprogram section B of DART 13 back to the previous input/output parameters.
In an alternative embodiment of the present invention, the escape sequence will be recognized if the predetermined $ character is sent (at the predetermined speed, parity, etc.) as the first character after a break has been provided for at least the minimum break time, without timing the lapse time or the maximum break time.
It will now be appreciated that the above method is an improved escape sequence which allows a user to establish communication with the control unit 10 even when the user does not know the input/output parameters of the port to which the user is connected.
Turn now to FIGS. 2A and 2B, which are a flow chart of the automatic document marking and escape sequences. Upon entering 50 the on-line mode control unit 10 sets 51 a high speed (HS) bit to 0 and an end document (ED) bit to 1. Control unit 10 also reads 51 the current time (T) in the TOD clock register and stores the current time (T) in registers TR1, TR2 and TR3 in RAM 12. Control unit 10 also performs 51 other operations such as RAM 12 refresh, indicator 37 refresh, read switch 36, send data to port A, etc.
Upon the interrupt 51 from PIA 16, control unit 10 updates 53 register TOD and then reads DART 13 to determine 54 if a break signal is present. If so, control unit 10 stores 55 the current time (T) in register TR3 in RAM 12 and then looks 56 at the HS bit. If HS=1, then control unit 10 reads 57 the current time (T) in the TOD register and computes an elapsed time TD2, where TD2=T-TR2, where TR2 is the time stored in register TR2. Control unit 10 then compares 60 TD2 to the maximum break time of 1500 milliseconds. If TD2 is less than the maximum break time, control unit 10 performs 61 the other operations.
If TD2 is equal to or greater than the maximum break time control unit 10 sets the HS bit to 0, sets 62 the input/output parameters of DART 13 back to the original setting, and then performs 61 the other operations. It will be appreciated that this is the maximum break time time-out provision.
If HS=0, control unit 10 computes 63 an elapsed time, TD2, where TD2=T-TR2. Control unit 10 then compares 64 TD2 to the minimum break time. If TD2 is less than the minimum break time control unit 10 performs 61 the other operations. If TD2 is equal to or greater than the minimum break time control unit 10 sets 65 the HS bit to 1, and sets the input/output (I/O) parameters of DART 13 to 9600 baud, 8 data bits, no parity bit, 1 stop bit, and performs 61 the other operations. It will be appreciated from the above that control unit 10 is looking at the break signal to determine if an escape sequence is in process.
If a break signal is not present control unit 10 stores 66 T in RAM 12 at TR2. Control unit 10 then determines 67 if there is data in DART 13. If there is no data present in DART 13 then control unit examines 70 the HS bit to determine if the escape sequence is in process. If the HS bit=1, then control unit 10 computes another elapsed time, TD3, where TD3=T-TR3+21 milliseconds. If TD3 is greater than or equal to the lapse time, 21 milliseconds, then control unit 10 sets 62 the HS bit to 0, sets the I/O parameters of DART 13 back to the original setting, and then performs the other operations. It will be appreciated that this implements the provision that the $ character must be received within 21 milliseconds of the dropping of the break signal. If TD3 is less than the lapse time, then control unit 10 performs 61 the other operations.
If 72 the HS bit=0, then control unit 10 stores 73 T in TR3 and then determines 74 if 70 the end of a document must be marked. If the ED bit=1, then there is no document in the replay buffer, or the end of any document has already been marked, so control unit 10 performs 61 the other operations.
If the ED bit=0, then there is a document in the replay buffer for which the end has not been marked. Control unit 10 then determines whether the spacing time has elapsed since the last data in DART 13. Control unit 10 therefore computes 75 another elapsed time TD1, where TD1=T-TR1, and compares 76 TD1 with the spacing time. If TD1 is less than the spacing time, control unit 10 performs 61 the other operations. If, however, TD1 is equal to or greater than the spacing time, control unit 10 determines that the document has ended, sets 77 the ED bit to 1, marks the end of the document, and performs 61 the other operations.
It will be appreciated from the above that control unit 10 is measuring the time since the last data in DART 13 to determine if the end of the document is to be marked.
If 67 data is present in DART 13 then control unit 10 must determine whether the data is the character of the escape sequence. Control unit 10 therefore stores 80 T in register TR3 and reads the data from DART 13. If 81 the HS bit is a 1, then a long break has previously occurred. If 81 the data is the $ character then control unit 10 enters 83 the command mode. If the data is not the $ character, then control unit 10 determines that the previous long break was not intended to signify the beginning of the escape sequence. Accordingly, control unit 10 will set 62 the HS bit to 0, set 62 the I/O parameters of DART 13 back to the original setting, and then perform 61 the other operations.
If 81 the HS bit is a 0, then the data in DART 13 is data in a document, so control unit 10 stores 84 T in RAM 12 at TR1. If 85 the ED bit is a 1, then this data is the first data of a new document, so control unit 10 sets 86 the ED bit back to 0, marks 86 the beginning of the new document, stores 86 the data D in the replay buffer, and then performs 61 other operations. However, if the ED bit was a 0, then this data is more data in an existing document so control unit 10 simply stores 87 D in the replay buffer and performs 61 other operations.
It will be appreciated that a window of 700 milliseconds (1500-800 milliseconds) is allowed for the break signal to be dropped. However, it will also be appreciated that the 800 millisecond and 1500 millisecond times are not critical and may be chosen to be other values. In fact, the maximum break time can, if desired, be deleted so that the break signal drop window never closes.
It will also be appreciated that the 21 millisecond lapse time is not critical and may be another value, or deleted so that the $ character can occur at any time after the break signal is dropped.
In the preferred embodiment, the minimum and maximum break times, the lapse time, the spacing time, and the predetermined character are programmable by the user when control unit 10 is in the command mode.
Also, in many applications, it is necessary to be able to send the break signal on to a modem or other device connected to another port. If control unit 10 detects the break signal, and there is no other data to be sent to the other device, then control unit 10 will send an idle signal to the other device. If, however, at the end of the maximum break time, control unit 10 is still detecting the break signal then control unit 10 will begin sending the break signal to the other device.
It will also be appreciated that, instead of updating the TOD register in RAM 12, control unit 10 could read the current time value (T) in the real time clock 20.
It will be appreciated that the flow chart of FIGS. 2A and 2B represents one way of accomplishing the desired results: automatic document marking, and escape sequence detection. It will also be appreciated that control unit 10 may perform other operations before and after each step shown above. Since many other variations and embodiments of the present invention may suggest themselves to those skilled in the art based upon the foregoing disclosure, the present invention is to be limited only by the claims below. | A multi-port message buffer which is responsive to an escape sequence. A control unit controls whether the message buffer is in a transparent mode or a command mode with respect to a particular port. The control unit monitors a data port for the escape sequence and, if the escape sequence is detected, the control unit causes the message buffer to enter into the command mode with respect to that port. The escape sequence is a break sequence of a predetermined period, followed within a predetermined time by a predetermined character at a predetermined data transmission speed. The escape sequence can therefore be detected even if the currently programmed data transmission speed for that particular port is unknown. | 6 |
RELATED APPLICATION
[0001] A related, copending application is entitled “Method of Forming a Transistor with a Bottom Gate,” by Thuy Dao, application Ser. No. 10/871,402, Attorney Docket No. SC13338TP, assigned to Freescale Semiconductor, Inc., and was filed on Jun. 18, 2004.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] This invention relates in general to semiconductor devices and more specifically to a back-gated semiconductor device with a storage layer and methods for forming thereof.
[0004] 2. Description of the Related Art
[0005] Traditional single gate and double gate Fully Depleted Semiconductor-on-Insulator (FDSOI) transistors have advantages related to reduced short channel effects and reduced un-wanted parasitic capacitances. However, when used as a non-volatile memory these transistors require programming, such as hot carrier injection (HCI) programming. HCI programming results in generation of holes because of impact ionization. Because of the floating nature of the body in such FDSOI devices, however, holes generated due to impact ionization may accumulate in the body of such FDSOI devices. Accumulated holes may then generate enough potential to cause problems, such as snap-back of the FDSOI devices.
[0006] Thus, there is a need for improved FDSOI transistors and methods of forming thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] The present invention may be better understood, and its numerous objects, features, and advantages made apparent to those skilled in the art by referencing the accompanying drawings.
[0008] FIG. 1 is a side view of one embodiment of two wafers being bonded together to form a resultant wafer, consistent with one embodiment of the invention;
[0009] FIG. 2 shows a side view of one embodiment of a bonded wafer, consistent with one embodiment of the invention;
[0010] FIG. 3 shows a partial cross-sectional side view of one embodiment of a wafer during a stage in its manufacture, consistent with one embodiment of the invention;
[0011] FIG. 4 shows a partial cross-sectional side view of one embodiment of a wafer during another stage in its manufacture, consistent with one embodiment of the invention;
[0012] FIG. 5 shows a partial cross-sectional side view of one embodiment of a wafer during another stage in its manufacture, consistent with one embodiment of the invention;
[0013] FIG. 6 shows a partial cross-sectional side view of one embodiment of a wafer during another stage in its manufacture, consistent with one embodiment of the invention;
[0014] FIG. 7 shows a partial cross-sectional side view of one embodiment of a wafer during another stage in its manufacture, consistent with one embodiment of the invention;
[0015] FIG. 8 shows a partial cross-sectional side view of one embodiment of a wafer during another stage in its manufacture, consistent with one embodiment of the invention;
[0016] FIG. 9 shows a partial cross-sectional side view of one embodiment of a wafer during another stage in its manufacture, consistent with one embodiment of the invention;
[0017] FIG. 10 shows a partial cross-sectional side view of one embodiment of a wafer during another stage in its manufacture, consistent with one embodiment of the invention;
[0018] FIG. 11 shows a partial cross-sectional side view of one embodiment of a wafer during another stage in its manufacture, consistent with one embodiment of the invention;
[0019] FIG. 12 shows a partial cross-sectional side view of one embodiment of a wafer during another stage in its manufacture, consistent with one embodiment of the invention;
[0020] FIG. 13 shows a partial cross-sectional side view of one embodiment of a wafer during another stage in its manufacture, consistent with one embodiment of the invention;
[0021] FIG. 14 shows a partial cross-sectional side view of one embodiment of a wafer during another stage in its manufacture, consistent with one embodiment of the invention; and
[0022] FIG. 15 shows a partial cross-sectional side view of one embodiment of a wafer during another stage in its manufacture, consistent with one embodiment of the invention.
[0023] Skilled artisans appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help improve the understanding of the embodiments of the present invention.
DETAILED DESCRIPTION
[0024] The following sets forth a detailed description of a mode for carrying out the invention. The description is intended to be illustrative of the invention and should not be taken to be limiting.
[0025] A back-gated non-volatile memory (NVM) device with its channel available for contacting to overcome the typical problem of charge accumulation associated with NVMs in semiconductor on insulator (SOI) substrates is provided. A substrate supports the gate. A storage layer is formed on the gate, which may be nanocrystals encapsulated in an insulating layer, but could be of another type such as nitride. A channel is formed on the storage layer. A conductive region, which can be conveniently contacted, is formed on the channel. This results in an escape path for minority carriers that are generated during programming, thereby avoiding charge accumulation in or near the channel. This is achievable with a method that includes bonding two wafers, cleaving away most of one of the wafers, forming the conductive region after the cleaving, and epitaxially growing the source/drains laterally from the channel while the conductive region is isolated from this growth with a sidewall spacer.
[0026] FIG. 1 shows a side view of two wafers 101 and 103 that are to be bonded together to form a resultant wafer ( 201 of FIG. 2 ), from which non-volatile memory cells may be formed, for example. Wafer 101 includes a layer 109 of gate material, a storage layer 107 , and semiconductor substrate 105 . By way of example, substrate 105 is made of monocrystaline silicon, but in other embodiments, may be made of other types of semiconductor materials such as silicon carbon, silicon germanium, germanium, type III-V semiconductor materials, type II-VI semiconductor materials, and combinations thereof including multiple layers of different semiconductor materials. In some embodiments, semiconductor material of substrate 105 may be strained. Storage layer 107 may be a thin film storage layer or stack and may be made of any suitable material, such as nitrides or nanocrystals. Nanocrystals, such as metal nanocrystals, semiconductor (e.g., silicon, germanium, gallium arsenide) nanocrystals, or a combination thereof may be used. Storage layer 107 may be formed by a chemical vapor deposition process, a sputtering process, or another suitable deposition process.
[0027] Referring still to FIG. 1 , by way of example, layer 109 includes doped polysilicon, but may be made of other materials such as, amorphous silicon, tungsten, tungsten silicon, germanium, amorphous germanium, titanium, titanium nitride, titanium silicon, titanium silicon nitride, tantalum, tantalum silicon, tantalum silicon nitride, other silicide materials, other metals, or combinations thereof including multiple layers of different conductive materials. An insulator 111 may be formed (e.g., grown or deposited) on layer 109 . In one embodiment, insulator 111 includes silicon oxide, but may include other materials such as e.g. PSG, FSG, silicon nitride, and/or other types of dielectric including high thermal, conductive dielectric materials.
[0028] Wafer 103 may include a substrate 115 (e.g., silicon) with an insulator 113 formed on it. In one embodiment, the material of insulator 113 is the same as the material of insulator 111 . By way of example, wafer 103 includes a metal layer (not shown) at a location in the middle of insulator 113 . This metal layer may be utilized for noise reduction in analog devices built from resultant wafer 201 .
[0029] Wafer 101 is shown inverted so as to be bonded to wafer 103 in the orientation shown in FIG. 1 . In one embodiment, insulator 111 is bonded to insulator 113 with a bonding material. In other embodiments, wafer 101 may be bonded to wafer 103 using other bonding techniques. For example, in one embodiment, wafer 101 may be bonded to wafer 103 by electrostatic bonding followed by thermal bonding or pressure bonding.
[0030] In some embodiments, wafer 101 does not include insulator 111 where layer 109 is bonded to insulator 113 . In other embodiments, wafer 103 does not include insulator 113 where insulator 111 is bonded to substrate 115 .
[0031] Wafer 101 may include a stress layer 106 formed by implanting a dopant (e.g. H+) into substrate 105 . In some embodiments, the dopant is implanted prior to the formation of storage layer 107 , but in other embodiments, may be implanted at other times including after the formation of storage layer 107 and prior to the formation of layer 109 , after the formation of layer 109 and prior to the formation of insulator 111 , or after the formation of insulator 111 . In other embodiments, the dopant for forming stress layer 106 may be implanted after wafer 103 has been bonded to wafer 101 .
[0032] FIG. 2 shows a side view of resultant wafer 201 after wafer 103 and 101 have been bonded together. The view in FIG. 2 also shows wafer 201 after a top portion of substrate 105 has been removed, e.g., by cleaving. By way of example, cleaving is performed by dividing substrate 105 at stress layer 106 . Layer 203 is the remaining portion of substrate 105 after the cleaving. One advantage of forming the layer by cleaving is that it may allow for a channel region to be formed from a relatively pure and crystalline structure as opposed to a semiconductor layer that is grown or deposited on a dielectric.
[0033] FIG. 3 shows a partial side cross-sectional view of wafer 201 . Not shown in the view of FIG. 3 (or in subsequent Figures) are insulator 113 and substrate 115 . After substrate 105 is cleaved to form layer 203 , an oxide layer 303 is formed over layer 203 . Layer 303 may be thicker than layer 203 . Next, as shown in FIG. 4 , a layer of polysilicon, to form conductive region 401 , may be deposited over oxide layer 303 after a middle portion of oxide layer 303 is patterned and then etched away. Thus, polysilicon layer is deposited directly on the transistor channel. The polysilicon layer may be doped in-situ or doped by implantation. Appropriate doping materials may be used depending on the type of device being manufactured. Conductive region 401 may be used as a well contact. If necessary, an appropriate pre-clean may be performed to remove any interfacial oxide layer. Conductive region 401 may remove minority carriers, such as holes from the channel region 203 of a transistor formed from wafer 201 .
[0034] Next, as shown in FIG. 5 , polysilicon layer forming conductive region 401 may be planarized by chemical-mechanical polishing, for example. Furthermore, a portion from top part of polysilicon layer forming conductive region 401 may be etched and a nitride cap 501 may be formed on top of conductive region 401 . In one embodiment, nitride cap 501 should be at least as thick as layer 203 so that nitride cap 501 may serve as an implant mask during implantation described with respect to FIG. 7 . This would ensure the doping of layer 401 is unaltered during implantation. Referring now to FIG. 6 , a liner 601 , such as an oxide liner may be formed after oxide layer 303 is removed.
[0035] Next, as shown in FIG. 7 , two implants 701 may be performed. First, amorphization implants may be performed in portions 707 / 709 . By way of example, germanium may be used to perform amorphization implants. Second, source/drain implants may be performed in portions 703 / 705 to form source/drain extensions. Appropriate n-type or p-type dopants may be used as part of this step. The region ( 203 ) under conductive region 401 may serve as a channel region. Referring now to FIG. 8 , a spacer 801 may be formed on the sidewalls of conductive region 401 (lined by liner 601 ). Spacer 801 may be made of multiple layers of dielectric materials. Spacer 801 may protect certain portions of portions 703 / 705 during subsequent processing. Next, exposed portions of portions 703 / 705 may be etched away.
[0036] Next, as shown in FIG. 9 , a second spacer 901 may be formed to protect sidewalls of portions 703 / 705 . Furthermore, portions 707 / 709 implanted with amorphization implants may be etched away. Referring now to FIG. 10 , an oxide layer 1001 may be deposited on wafer 201 . Next, as shown in FIG. 11 , selected portions of oxide layer 1001 may be etched away. Etching of selected portions of oxide layer 1001 may result in partial etching of liner 601 , as well. FIG. 12 shows a partial cross-sectional side view of wafer 201 after structures 1201 and 1203 are epitaxially grown on the exposed sidewalls of channel region (including portion 203 ).
[0037] Referring to FIG. 13 now, an amorphous silicon layer 1301 / 1303 may be deposited. Amorphous silicon layer 1301 / 1303 may be subjected to chemical mechanical polishing and etched back. Next, as shown in FIG. 14 , a photoresist layer 1401 may be formed on top of a selected portion of wafer 201 and source/drain implants 1403 may be made forming doped source/drain regions 1405 and 1411 . Next, as shown in FIG. 15 , silicides 1501 , 1503 , and 1505 may be formed after nitride cap 501 is stripped. Gate silicide 1503 may be formed on top of conductive region 401 . By way of example, silicides may be formed using a silicide implantation (e.g., cobalt or nickel) followed by a heat treatment. Alternatively, silicides may be formed by depositing a layer of metal over the wafer and reacting the metal with the underlying material.
[0038] By way of example, the semiconductor device formed on wafer 201 may be used as a non-volatile memory. The non-volatile memory may include cells formed of the semiconductor device, which may be programmed using techniques such as, hot carrier injection. For example, using HCI, one bit per cell may be stored in storage layer 107 by applying a positive bias voltage to gate 109 , applying a positive voltage to drain region 1411 , grounding source region 1405 , and applying a negative voltage to conductive region 401 or grounding conductive region 401 . HCI programming may result in generation of minority carriers, such as holes because of impact ionization. Conductive region 401 may provide an escape path for holes thereby preventing accumulation of holes in channel region 203 .
[0039] In the foregoing specification, the invention has been described with reference to specific embodiments. However, one of ordinary skill in the art appreciates that various modifications and changes can be made without departing from the scope of the present invention as set forth in the claims below. Accordingly, the specification and figures are to be regarded in an illustrative rather than a restrictive sense, and all such modifications are intended to be included within the scope of present invention.
[0040] Benefits, other advantages, and solutions to problems have been described above with regard to specific embodiments. However, the benefits, advantages, solutions to problems, and any element(s) that may cause any benefit, advantage, or solution to occur or become more pronounced are not to be construed as a critical, required, or essential feature or element of any or all the claims. As used herein, the terms “comprises,” “comprising,” or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. | A method of making a semiconductor device includes providing a first wafer and providing a second wafer having a first side and a second side, the second wafer including a semiconductor substrate, a storage layer, and a layer of gate material. The storage layer may be located between the semiconductor structure and the layer of the gate material and the storage layer may be located closer to the first side of the second wafer than the semiconductor structure. The method further includes boding the first side of the second wafer to the first wafer. The method further includes removing a first portion of the semiconductor structure to leave a layer of the semiconductor structure after the bonding. The method further includes forming a transistor having a channel region, wherein at least a portion of the channel region is formed from the layer of the semiconductor structure. | 1 |
REFERENCE TO RELATED APPLICATIONS
This application is a national stage application under 35 USC 371 of International Application No. PCT/EP2011/050831, filed Jan. 21, 2011, which claims the priority of German Application No. 10 2010 005 286.8, filed Jan. 21, 2010, the entire contents of which are incorporated herein by reference.
FIELD OF THE INVENTION
The invention relates to a wind energy installation having a rotor for driving a generator, wherein the rotor has blades which are both adjustable in terms of pitch and heatable by blade heating.
BACKGROUND OF THE INVENTION
Wind energy installations are suitable as local generators of electrical energy, particularly also for use in thinly populated areas with favorable wind conditions. Many of these thinly populated areas are in zones with an adverse climate. These also include areas with a cold climate, in particular. In order to toughen up wind energy installations for operation under “cold climate” conditions, blade heating is usually necessary for the rotor blades. This is because it has been found that, without such heating, ice forms or collects on the rotor blades during operation, said ice having disadvantageous effects in multiple respects. Firstly, it alters the aerodynamic profile of the rotor blades, which usually results in significant impairment precisely when the rotor blades have a very advanced aerodynamic design. Furthermore, the formation of ice increases the weight of the rotor blade, which increases the forces to be absorbed by the suspension of the rotor blades; this applies particularly during operation at relatively high speeds and correspondingly growing centrifugal forces or when there are imbalances in the hub as a whole which are caused by different ice formation on the respective rotor blades. Finally, there is also a not inconsiderable risk to persons and objects in the vicinity of the wind energy installation as a result of ice being cast, i.e. as a result of pieces of ice becoming detached from rotor blades and being flung away. In general, the wind energy installation is shut down when there is ice formation on the rotor blades. In order to avoid these disadvantages, blade heating may be provided. On account of the size of the rotor blades and sometimes harsh climatic conditions, however, a relatively large amount of heating power is required for the blade heating. Providing said heating at the location at which it is needed, namely in the hub of the rotor, requires some additional complexity, resulting in additional cost.
In order to be able to still supply power to a large electrical load, such as a blade heater, without amplifying the power available in the hub, a design has become known in which the wind energy installation is shut down while the rotor blades are being heated (DE 103 23 785 A1). Although this has the disadvantage that no further electrical power is generated by the wind energy installation during the phases in which the rotor blades are being heated, this has the advantage that barely any power needs to be expended for the individual requirements of the wind energy installation during the shutdown, and hence all of the electrical power available in the hub can be used for heating the rotor blades. Usually, heating takes place over a period of up to 15 minutes, and after that the wind energy installation is started up again. Although heating using a stopping device of this type has proven itself in principle, this still has the disadvantage that no electrical energy is generated during the heating time, that is to say that the yield is reduced.
This is made even worse by the fact that restarting afterwards is extremely time consuming, which further reduces the production of energy by the wind energy installation. Above all, however, a serious disadvantage is that the ice formation per se is not prevented and hence a risk to the surroundings cannot be ruled out.
SUMMARY OF THE INVENTION
The invention is therefore based on the object of improving wind energy installations of the type cited at the outset such that large loads, such as a blade heating apparatus, can also be operated on the hub and at the same time complex amplification of the supply of power is avoided.
The solution according to the invention lies in the features as broadly described herein. Advantageous developments are the subject matter of the detailed embodiments described below.
In a wind energy installation comprising a rotor having blades and a generator, which is driven by the latter, for generating electrical energy, wherein the blades are adjustable in terms of pitch and a pitch system for adjusting the pitch angle of the blades is provided which is fed from a hub power source, the invention provides a pitch power controller which dynamically distributes the power provided by the hub power source between the pitch system and the supplementary electrical load and in addition acts on the pitch system such that the power draw by the latter is reduced in the high-load mode.
A few terms which are used will first of all be explained below:
A supplementary electrical load is understood to mean a device which is arranged on the rotor hub and provides additional functionality which is not required for basic operation of the wind energy installation. In particular, this includes large loads which each independently have a power draw which is at least one fifth, preferably half, of the electrical power available in the hub. Examples of such supplementary loads are blade heating devices for the rotor blades, particularly with resistance heating or fan heaters, air-conditioning appliances for dehumidifying the hub, cooling appliances for hot-climate versions, powerful warning and protective devices, such as high-intensity hazard lighting for the rotor blades, or particularly complex measured-value capture systems, such as LIDAR or phased-array radar systems for wind or turbulence recognition and determination.
A high-load mode is understood to mean that the wind energy installation is set up such that the supplementary electrical load is supplied with power as a matter of priority. The difference over the normal mode is thus that in the normal mode the priority is given to speed regulation for the wind energy installation, which allows optimum energy yield, and the supplementary electrical load is not operated or is operated only to a small extent.
Dynamically distributed is understood to mean that the power transmitted from the pitch power controller to the pitch system or the supplementary electrical load is variable during operation. In particular, dynamically distributed may also mean that the pitch power controller regulates the power requirement of the supplementary electrical load. Dynamic distribution can therefore also be effected by switching on or switching off or by setting the operating point of the electrical loads.
A hub power source is understood to mean a limited-capacity source for electrical energy which provides electrical power in the rotor assembly. Usually, this will be a power-limiting transmission system of the wind energy installation on which the rotor is arranged so as to be able to rotate. By way of example, this transmission system may be a slipring, and in this case the hub power source is limited by the maximum power which can be transmitted by the slipring. Alternatively, the hub power source can also generate the electrical power autonomously, for example using a storage battery and/or a shaft generator.
The invention is based on the idea of splitting the electrical power provided by the hub power source in the rotor differently in the high-load mode than in the normal mode, namely such that the electrical power drawn by the pitch system is reduced and hence kept within limits which are such that a large portion of the electrical power can be provided for operating the supplementary electrical load. The supplementary electrical load can thus be operated at full power without restrictions. In the case of a blade heater, this means the full heating effect, as has conventionally been able to be achieved only when the wind energy installation has been shut down. In essence, the invention thus provides for dynamically modified power branching, with the power draw by the pitch system being reduced in the high-load mode and hence additional power being provided for operating the supplementary electrical load. Amplification of the hub power source or substantial operating restrictions as in the prior art can thus be avoided. By virtue of the invention, the conventional hub power source which is already present is thus sufficient despite the substantial power requirement for the supplementary electrical load. No additional complexity for amplifying the hub power source is required.
Preferably, the pitch power controller is designed such that the power is limited not rigidly but rather adaptively. To this end, an adaptation device is expediently provided which monitors the pitch power controller and acts on it. The adaptation device may be of various design. Thus, in a first version, the adaptation device may have a current surveillance module. In this case, the power drawn by the pitch system is reduced when the hub power source is loaded to an adjustable maximum degree (for example 90%). This ensures that even with a high level of activity there is always sufficient power available for the supplementary electrical load. Preferably, this comprises a load sensor. This may be produced on the pitch drive, for example as a current sensor (direct measurement), or the power draw can be determined from signals for pitch adjustment rate and acceleration (indirect measurement); if it turns out that the pitch system is under a high load in this case, appropriate action is taken to reduce the power draw. Preferably, the current surveillance module is designed to act on parameters of the pitch system, for example to reduce the gain of a regulator or the maximum permissible pitch adjustment rate in the pitch controller.
In addition, provision may be made for the adaptation device to have a restrictor module. This determines an appropriate restricted operating point for the respective operating point of the wind energy installation, at which restricted operating point the speed and power generated by the generator are reduced. This increases the reserve up until the respective limit values (speed and power) have been reached, so that subsequently there is significantly less pitch activity required by utilizing this reserve.
Expediently, the restrictor module is also designed to reduce the regulatory quality of the pitch control system. This expands tolerance bands and consequently reduces the activity of the pitch system, as a result of which there is ultimately more power available for the supplementary electrical load from the hub power source.
For protection purposes, the adaptation device may also be provided with an interruption module. This is designed to output a suspend signal to the pitch power controller, and hence to disable the high-load mode, when predetermined states of the wind energy installation occur. Preferably, the interruption module is connected to a device for recognizing a voltage dip. Hence, in the event of a system disturbance during a voltage dip, the wind energy installation is able to interrupt the high-load mode, and hence to make all of its resources available for handling the voltage dip. Furthermore, a device for recognizing a system return may be provided. However, in the event of the system returning, startup of the wind energy installation and the alterations in the pitch which are required for this have priority, as a result of which the supplementary electrical load is expediently disconnected for this. The interruption module may have further signal inputs for particular high-load states of the pitch system, particularly for the reaching of maximum current in the pitch system or the implementation of emergency running.
The invention also extends to a method according to the independent claim. For more detailed explanation, reference is made to the description above.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is explained below using an exemplary embodiment with reference to the appended drawing, in which:
FIG. 1 : shows an overview illustration of a wind energy installation based on an exemplary embodiment of the invention;
FIG. 2 : shows a schematic illustration of the electrical components in the hub of the wind energy installation shown in FIG. 1 ; and
FIG. 3 : shows status graphs over time.
DETAILED DESCRIPTION OF THE INVENTION
A wind energy installation based on an exemplary embodiment of the invention comprises a gondola 11 arranged on a tower 10 so as to be able to pivot in azimuthal direction. The front of said gondola has a rotor 2 arranged on it so as to be able to rotate, which drives a generator 13 via a generator shaft 12 in order to generate electrical energy. In the exemplary embodiment shown, the generator 13 is in the form of a dual-fed asynchronous generator and is interconnected with a converter 14 . The electrical power provided by the generator 13 and the converter 14 is routed via a power cable 15 , running in the tower 10 , to the base of the tower, where it is connected to a machine transformer 16 for the purpose of outputting the generated electrical energy at a medium voltage level.
In addition, the gondola 11 contains an operating control system 17 . This is designed to actuate the individual systems of the wind energy installation, and it is furthermore connected for communication purposes, for example via a radio interface 18 , to superordinate control devices, such as a farm master on a wind farm and/or system control centers belonging to a power supply system operator.
The rotor 2 comprises a plurality of rotor blades 21 which are arranged so as to be adjustable in terms of their pitch angle θ on a hub 20 at the end of the generator shaft 12 . For the purpose of adjusting the pitch angle θ, a pitch system 4 is provided which comprises an annular gear 41 which is arranged at the blade root of the respective rotor blade 21 and with which a drive sprocket on a server motor 42 arranged firmly on the hub engages. For the purpose of actuating the pitch system 4 , a dedicated pitch control system 43 may be provided in the hub. The pitch control system 43 receives guidance signals from the operating control system 17 . In addition, the hub 20 contains a hub power source 40 for the pitch system 4 . The hub power source 40 may be a slipring, in particular, by means of which electrical power is routed from the gondola 11 into the hub 20 . However, it may alternatively or additionally also be a battery 40 ′ or a shaft generator 40 ″ running on the shaft 12 . The way in which the pitch system 4 works is such that a target value is prescribed for the pitch angle θ s by the operating control system 17 , and said target value is then adjusted by the pitch control system 43 , by operating the drive motor 42 which acts on the annular gear 41 of the rotor blades 21 , by rotating the rotor blades 21 until the correct pitch angle θ has been reached.
The rotor blades 21 are also provided with a blade heater 5 , which is preferably arranged at least in the region of a nose strip of the rotor blades 21 . In the exemplary embodiment shown, the blade heater 5 is in the form of an electric heating element. It is a supplementary electrical load in the hub 20 , which supplementary electrical load requires considerable electrical power in the heating mode (“high-load mode”). Energy is supplied by using said hub power source 40 , which also supplies power to the pitch system 4 . In order to split the power between the pitch system 4 on the one hand the blade heater 5 on the other, the invention provides a pitch power controller 6 . This has a control block 60 and a switching block 61 having a power input and two power outputs. The power input has the hub power source 40 connected to it. One of the two outputs has the pitch system 4 connected to it, and the other of the two outputs has the blade heater 5 connected to it. The pitch power controller may be designed for digital changeover, which involves only one of the two systems being supplied with power at a time; in the exemplary embodiment shown, however, it is meant to be a system which can split the power, so that both systems can also be supplied with power simultaneously (albeit not necessarily with power of the same magnitude).
The switching block 61 of the pitch power controller 6 is operated by a control block 60 . This is designed to reduce the power drawn by the pitch system 4 in a heating mode. To this end, the control block 60 is connected to the pitch control system 43 by means of a first signal line 62 . The effect achieved by this is that the power draw by the pitch system 4 is reduced, and there is thus always sufficient power available for the blade heater 5 for the heating mode.
The pitch power controller 6 has an adaptation device 8 interacting with it. This has a plurality of functional modules, namely a current surveillance module 81 , a restrictor module 82 and an interruption module 83 . The current surveillance module 81 is designed to monitor the operation of the pitch system 4 by means of a power sensor 44 in the heating mode. If the pitch system is operated such that a critical value for the power draw is reached (for example if, together with the blade heater, 90% of the power of the hub power source 40 were demanded), the hub power source 40 is protected from overload by influencing regulator parameters of the pitch system control system 43 . In particular, limitation of the adjustment rate and acceleration for the pitch drive 42 can be prompted by this means.
The restrictor module 82 is designed to operate the wind energy installation at relatively low load as a preventive measure. To this end, on the basis of the normal operating point which is obtained for the respective ambient conditions, particularly in relation to the parameter speed and power, offset values are formed which are deducted from the values for the normal operating point so as thereby to produce modified target values for the parameters at a modified operating point. To this end, an interface 84 is provided which applies the altered data for the operating point to the operating control system 17 .
Specifically, this means that, for example on the basis of an operating point with a speed n B of 20 revs/min, in a partial-load operating situation the target speed for the heating mode a modified operating point with a lowered speed n B ′ of 16 revs/min is determined, with the tolerance limits and the action threshold of the pitch system control system 43 not following accordingly, however. There is therefore a substantial buffer, which means that even in the event of incident winds which are suddenly stronger, it is not necessary for the pitch system 4 to be operated, as a result of which the power provided by the hub power source 40 can be used almost to the full extent for the blade heater 5 . A similar situation applies to the full-load operating situation. In this case, instead of the speed, the operating point for the power would be lowered accordingly, which results in an appropriate power reserve which in turn reduces the probability of the pitch system 4 being switched on accordingly.
The interruption module 83 has a plurality of signal inputs, which are each designed to detect particular states. Thus, a first signal input has a detector 85 for a voltage dip arranged at it. It should be noted that the detector 85 may be a standalone component or a connection to another device, which is already present anyway and performs voltage dip detection (for example in the operating control system 17 ). When the occurrence of a voltage dip is detected in this manner, the interruption module 83 acts on the pitch power controller 6 such that the power which the hub power source 40 provides for the blade heater 5 is severely reduced or even switched off completely. The effect achieved by this is that in such an extra ordinary operating situation the pitch system 4 is supplied with power to a sufficient degree to be able to make even large pitch changes at a high pitch adjustment rate and acceleration. Accordingly, a detector 86 for system return, a detector 87 for pitch emergency running and in addition a sensor 89 for recognizing when the maximum flow of current from the hub power source 40 has been reached are provided. In addition, an overspeed detector 88 is connected, so that when a limit speed is reached the suspend signal is output by the interruption module 83 . If this furthermore involves a limit value for a speed acceleration being exceeded, a rotor brake 22 is operated.
In addition, an enabling device 18 may be provided which is operated by the pitch system 4 . Said enabling device comprises two inputs, one connection for an enabling signal which is output by the pitch system 4 and one connection for a request signal for the supplementary electrical load, which is output by the operating control system 17 . An output of the enabling device 80 is connected to the pitch power controller. The enabling device 80 interacts with the pitch power controller 6 such that in the event of predetermined installation states of the supplementary electrical loads occurring the heating system 5 is switched on and changed to the heating mode. This can be brought about directly by the signal applied to the enabling device 80 by the pitch system 4 , as a result of which the pitch power controller 6 assigns the power to the heating system 5 . Alternatively, a two-stage enabling system may be provided, with the operating control system 17 applying a request signal for the heating mode to the enabling device 80 , which request signal is connected to the pitch power controller only if the enabling signal from the pitch control system 4 is also present. Examples of such operating states are, in particular, installation operation of partial load, when the pitch system 4 is in a kind of sleep mode, installation operation for regular wind with only minor pitch activities, or else installation shutdown.
An example of a mode of action is shown in FIG. 3 . FIG. 3 a shows various phases with or without heating mode switched on. In phase I, the heating mode has not yet been switched on, i.e. the wind energy installation is being operated in the normal mode. In the subsequent phase II, the heating mode is activated. FIG. 3 b shows the speed values which have been adjusted by the pitch system 4 . FIG. 3 c shows the activity of the pitch system 4 in the form of operation of the pitch actuating drive 42 for adjusting a pitch angle Θ, with which the speed prescribed by the operating point as shown in FIG. 3 b is achieved. It can be seen that compliance with the speed preset in phase I requires brisk activity by the pitch system. At the time t 1 , the restrictor module 82 determines a modified operating point with a relatively low speed n B′ . The pitch power controller 6 is activated and assigns a large portion of the power to the blade heater 5 . In addition, the current surveillance module 81 is operated. The effect can be seen in FIGS. 3 b and c , where the speed discrepancies are greater in phase II than in the preceding operating phase I without heating mode, but these discrepancies are noncritical on account of the preemptive speed lowering and do not exceed the speed n B of the previously set operating point; the mode is therefore safe. Since greater discrepancies can therefore be permitted, the activity of the pitch system 4 in phase II is reduced. This can easily be seen in FIG. 3 c . Since the actuating amplitudes and the rate and also acceleration are reduced, the current draw by the pitch system 4 is correspondingly lower, which means that there is sufficient power available for operation of the blade heater 5 .
This state continues until a short occurs in the system in phase IIb. This short is recognized by the detector 85 and is applied as a signal to the interruption module 83 . The interruption module then disables the heating mode by actuating the pitch power controller 6 such that the power is provided only for the pitch system 4 . The power for the blade heater 5 is therefore removed. Accordingly, the modified operating point and the restriction in respect of the activity of the pitch system are also removed, which means that the wind energy installation can react to this fault situation to the full extent. This phase IIb continues until the system return is recognized by means of the detector 86 . The return to the heating mode then occurs in phase IIc, said heating mode being executed in accordance with phase IIa.
It can also be assumed that an overspeed in the rotor 2 occurs (for example on account of an undervoltage in the system to which the transformer 16 is connected). The speed exceeds the upper speed limit n H at the time t 4 with a keenly rising tendency (i.e. large speed acceleration). This is recognized by the overspeed detector 88 , and the interruption module 83 operates the pitch power controller 6 such that the power is provided only for the pitch system 4 , as a result of which said pitch system can react to the overspeed with the full activity. In order to completely rule out a risk to the safety of the wind energy installation resulting from the high speed acceleration, the rotor brake 22 is additionally operated in order to stabilize the speed (phase IId). | A wind energy plant comprising a rotor having blades and a generator driven by said rotor for generating electric energy. The pitch of the blades can be adjusted and a pitch system for adjusting the pitch angle of the blades is provided, which is supplied by a hub power source. An additional electric load is provided on the hub. A pitch power control device is provided which dynamically distributes the power of the hub power source between the pitch system and the additional electric load and further acts on the pitch system such that its power consumption during high-load operation is reduced. Thus, the power consumption of the pitch system during high-load operation can be reduced and additional power provided for operating the additional load. Even large additional loads, such as a blade heater, can be operated in this way, without having to boost the hub power source. | 5 |
[0001] This application claims benefit of the previously filed Provisional Patent Application No. 60/598,316, filed Aug. 3, 2004, by Dharmesh Shah, the specification and attachments of which are incorporated herein by reference, and is entitled to that filing date for priority.
FIELD OF INVENTION
[0002] This invention relates to a system for the secure and protected processing of securities transactions.
BACKGROUND OF INVENTION
[0003] The SEC is considering whether or not to impose a “hard” 4:00 p.m. ET cutoff by which time funds and trading systems would need to have received transactions in order for those transactions to have that day's prices applied. Details on the SEC's position can be read in the proposed rule amendments published as “Amendments to Rules Governing Pricing of Mutual Fund Shares,” Release No. IC-26288, RIN 3235-AJ01, available on the Internet at: http://www.sec.gov/rules/proposed/ic-26288.htm, and which is incorporated herein by reference.
[0004] The 4:00 p.m. cutoff represents a substantial obstacle to entities such as mutual fund and retirement plan providers who require a substantial period of time to ensure after a transaction is initiated that a transaction complies with applicable restrictions or requirements. Such entities would be at a significant disadvantage in securities markets if they were, in effect, required to initiate a transaction significantly in advance of a 4:00 p.m. cutoff in order to complete the transaction by that time. In its proposed rule amendments, the SEC specifically cites a possible alternative to the 4:00 p.m. hard cutoff which would involve a number of steps including the “electronic or physical time-stamping stamping of orders in a manner that cannot be altered or discarded once the order is entered . . . ”.
[0005] The entities described above currently use a variety of recordkeeping systems and proprietary platforms, including but not limited to SunGard's OmniPlus system. OmniPlus primarily maintains data in its VTRAN file (which is one file that is part of the OmniPlus master files). VTRAN, like the other OmniPlus files, are kept in Microfocus format on PC and Unix platforms. OmniPlus keeps a set of “audit fields” on the VTRAN record, including timestamps for activities such as transaction creation, posting, editing, and updating. In addition to each timestamp, the UserID of the user conducting the activity is also tracked. However, data kept in the VTRAN file (including all audit field information) does not seem to be encrypted in any fashion. As such, sufficiently sophisticated users could modify VTRAN data using low-level tools. Such modifications would also bypass conventional means of detection.
[0006] The primary administration interface to OmniPlus is OmniStation, a Windows (16-bit) application. Users of OmniStation generally include administrators, account manager, relationship manager, and data-entry personnel, among others. Users of OmniStation must be authenticated via OmniSecurity, a subcomponent of OmniPlus that allows definition of users, scope of access, and functional privileges.
[0007] OmniConnect is an API (application programming interface) offered by SunGard to allow development of third-party applications that interact with OmniPlus. OmniConnect is a based on DDMS (Distributed Data Management System) a proprietary messaging protocol designed and developed by SunGard EBS. A variety of applications use either DDMS directly or OmniConnect. In either case, the data being passed between the client and server is identical. Each packet that is sent via DDMS (which includes all packets sent by OmniConnect) must include authentication credentials (UserID/Password). These credentials are used to validate the user (or application) against OmniSecurity. These are the same type of credentials provided to OmniStation users. The UserID that is transmitted on the DDMS packet is in clear text. The password is encoded (not encrypted) using a proprietary SunGard algorithm.
[0008] A variety of potential vulnerabilities that exist within many OmniPlus environments. Any of these vulnerabilities could be exploited to conduct unauthorized transaction activity and avoid the intent of the SEC's hard cutoff time. For example, after the specified cutoff time, users with sufficient security could add transactions to the appropriate transaction folder using OmniStation. These transactions would be processed along with the authorized transactions. In this case, the VTRAN record would maintain audit fields regarding the user that created the transaction and the date/time the transaction was added to the system. Similarly, after the cutoff time, transactions can be deleted from the current day's transaction folder using OmniStation. Such deletions would not have a permanent audit trail and the prior audit fields (regarding transaction creation) would be lost.
[0009] Another problem exists in that various front-office systems (e.g., voice, web, etc.) may use different code to determine the trade date for a transaction. Thus, it is possible for these systems to be out-of-synch and apply business rules in an inconsistent manner. Each of these systems provides its own mechanism for specifying the cutoff time, which then controls the trade date by means of specific transaction folder naming.
[0010] Accordingly, sufficiently savvy or knowledgeable users with knowledge of low-level data structures could bypass all traditional software systems (OmniPlus, OmniStation, etc.) and directly delete or modify transactions stored within that system. Such changes would completely bypass all current audit trail mechanisms in place.
[0011] Thus, what is needed is a system that would allow retirement plan providers and similarly-situated entities to specifically address this need to secure their internal systems and preserve a secure database of transaction data to prevent altering or deleting of trades in violation of the SEC rules.
SUMMARY OF THE INVENTION
[0012] The present invention provides for a system and method for providing for the secure and protected processing of transactions. In particular, the invention prevents altering or deleting of trades in violation of the SEC rules. An embodiment of the invention comprises a suite of software programs and components that, when implemented in concert, allow recordkeepers to address late-trading and other unauthorized transaction activity. The invention also can be implemented in conjunction with a variety of recordkeeping systems and proprietary platforms, including but not limited to SunGard's OmniPlus system, Relius, TrustMark WyStar and proprietary platforms.
[0013] The key element of the invention is a secure vault within which transactions are stored, protected and verified. As transactions are created during normal business processing, they are passed through a computer system, either using real-time or batch interfaces. All transactions stored in the vault are time-stamped, encrypted and tagged for later validation. By using sophisticated, industry-accepted methods for tagging and protecting the integrity of the data, the invention ensures the integrity of each transaction and that system rules (such as cutoff times) have been enforced and applied consistently.
[0014] By using a middleware approach, the present invention can be implemented within or in conjunction with existing recordkeeping environments. The unique approach to intercepting existing data flows allows the present invention to be implemented with no changes to the recordkeeping software or the front-end applications (e.g., voice response, web, call center, administration, etc.). This allows the core benefits of the invention to be achieved with minimal change and risk in the existing software.
[0015] Still other advantages of various embodiments will become apparent to those skilled in this art from the following description wherein there is shown and described exemplary embodiments of this invention simply for the purposes of illustration. As will be realized, the invention is capable of other different aspects and embodiments without departing from the scope of the invention. Accordingly, the advantages, drawings, and descriptions are illustrative in nature and not restrictive in nature.
DESCRIPTION OF THE DRAWINGS
[0016] FIG. 1 is a diagram of one embodiment the subject invention in relation to client applications and a recordkeeping system.
DETAILED DESCRIPTION OF THE INVENTION
[0017] The present invention relates to a computer-based secure system for providing for the secure and protected processing of securities transactions. Referring now to the numerous figures, wherein like references identify like elements of the invention, FIG. 1 illustrates an overview of a secure system 10 utilized according to a preferred form of the invention.
[0018] The secure system 10 acts as a secure “middleware” component that resides between client applications (e.g., voice, web, call center, etc.) 1 and the recordkeeping system 2 . As shown in FIG. 1 , one embodiment of the invention is designed to work with a SunGard OmniPlus system as the recordkeeping system 2 . Other embodiments of the invention, however, can be implemented in conjunction with a variety of other recordkeeping systems and proprietary platforms, including but not limited to Relius, TrustMark WyStar and proprietary platforms.
[0019] Input from client applications 1 is received by a secure gateway 11 . In an embodiment of the invention designed to work with a SunGard OmniPlus system as the recordkeeping system 2 , the secure gateway 11 is an OmniPlus port listener, which listens for OmniConnect and DDMS packets. This port listener 11 resides between all client applications 1 (e.g., OmniStation, OmniVoice 2000, Pyramid applications and OmniConnect) and processes each packet that is destined for the recordkeeping system 2 (e.g., OmniPlus).
[0020] The secure gateway 11 intercepts all transaction-related data packets (especially add/delete/update). These packets are processed and stored within the invention's relational database 13 , which acts as a secure vault, either in addition to or in place of the recordkeeping system's 2 own database (e.g., OmniPlus VTRAN). Each transaction processed through by the present invention goes through specialized handling code for encryption, hashing and other forms of protection.
[0021] The secure gateway 11 also may optionally log and track every packet that is passed through the gateway 11 . This logging includes detailed information about the packet, including but not limited to the UserID, Packet Name, date/time, PlanID, ParticipantID, and the like. Logging information is stored in the relational database 13 , thereby allowing for sophisticated reporting and querying.
[0022] The secure gateway 11 also allows creation of low-level “rules” to prevent certain types of activity based on the user, time of day, or type of activity. For example, a rule could be defined to prevent all transaction deletions from 4:00 p.m. to 10:00 p.m.
[0023] The secure gateway 11 further can override and centralize folder determinations by client applications 1 or recordkeeping systems 2 (e.g., OmniPlus VTRAN's folder determination). Instead of each client application 1 (e.g., OmniStation, OmniVoice 2000, Pyramid, etc.) making its own determination of the trade-date (and hence the transaction folder), the packet interceptor in the secure gateway 11 could detect that a transaction is being added, and compare the current time to the cutoff time and override the folder name. This would be transparent to the client application 1 .
[0024] The relational database 13 is used as a secure vault to store transactional data, the audit log, and other system information. Examples of such databases 13 include but are not limited to SQL Server, Oracle or DB2. Such databases 13 are a proven mechanism for storing and managing large volumes of information.
[0025] The secure transaction processor 12 ensures the integrity of transactional data, and employs sophisticated mechanisms to make the transactional data tamper-resistant. The secure transaction processor 12 ensures that all transactions that are created are properly logged in an encrypted form, and that the log itself is tamper-resistant. Once a transaction is created, all modifications to that transaction are securely logged. Based on non-modifiable cutoff times, transactions will be “frozen” preventing any further modifications of the transaction (including, but not limited to the trade-date, financial amounts, funds, etc.) Sophisticated tamper-resistance mechanisms will prevent low-level “hacks” of the transactional data. Any such hacks will render transactions invalid and will be logged to the system.
[0026] The secure transaction processor 12 also has the ability to prevent and detect unauthorized deletions of transactions after the cutoff time. Once a transaction has been committed to the system and the cutoff time is passed, the transaction is no longer capable of being deleted through any authorized application or system. Attempts to delete transactions using low-level data hacks (such as bypassing authorized systems) will be detected and prevented.
[0027] Interaction with the system is accomplished through a user interface 15 and an application programming interface (API) 14 . In one embodiment of the present invention, the API 14 is an XML/SOAP API. The API 14 provides access to all of the critical capability that is available in the present invention, including secured algorithms. The API 14 supports functions such as creating transactions (including Omni transactions), verifying the integrity of an existing transaction that has already passed downstream, researching a transaction by retrieving the secure audit trail of all activity on that transaction (e.g., add, change, delete, commit, etc.), and determining the folder name to use for a transaction.
[0028] A secure batch transfer module 16 works with the secure transaction processor 12 to migrate a set of transaction data from the secure system to a target system (such as OmniPlus or some other trading system). The secure batch transfer module has the capability to validate the integrity of all transactions in the secure database vault (i.e., ensures that the vault had not been tampered with using unauthorized means), select the valid pool of transactions that should be migrated, verify that each transaction in the migration pool is valid and has not been altered inappropriately, store within each transaction an irreproducible “secure token” that can be used to verify that the origin of the transaction was the secure system, and transmit the batch of transactions to the target system.
[0029] The present invention implements the above components to meet the expected regulatory requirements placed on recordkeepers by the SEC, and is specifically designed from the ground-up to focus on these requirements and keeping the solution as simple and deployable as possible.
[0030] One such requirement is time synchronization, i.e., a single, trusted source for determining the current date and time. Ideally, this source resides on a single system that self-updates using an externally available time source. An embodiment of the present invention meets this need by having all critical algorithms and logic reside on a single server (i.e., the “TransactionVault” server). This server uses the industry-accepted NTP (Network Time Protocol) to periodically synchronize the system time with a trusted source. In addition, the secure system keeps an audit trail of each synchronization event within its secure database.
[0031] All trades/transactions submitted to the secure system will be time-stamped using the trusted time as established by the synchronization system. Once a transaction has been time-stamped, the transaction cannot be modified in any way (as described below). The default configuration that is shipped with each secure system is to synchronize the time once every hour. Each synchronization event is logged in the secure audit log for later verification.
[0032] By default, the cutoff time for most trades will be 4:00 ET, or earlier (as defined by regulation). This time may be adjusted for specific dates (such as holidays). To accommodate this, the secure system has a calendar that takes into account the end of business for these pre-defined days. The business calendar is kept in the secure configuration, which cannot be modified by clients or anyone else other than authorized personnel.
[0033] A centralized algorithm within the secure system software uses a combination of the current trusted time (based on synchronization) and the business calendar to determine the trade date for the transaction (i.e., the date used for pricing).
[0034] Some users of an embodiment of the subject invention may need to configure the system in specific ways (such as defining over-rides for the cutoff time). To ensure the integrity of the system, each of these configurable settings is stored in a secured (encrypted) file that is supplied by provider of the secure system. As such, clients requiring variations from the default configuration need to contact the provider. With proper approvals and documentation, the provider can supply customized configurations that are specific to an individual client. By securing the configuration, the integrity of the system is ensured so that users can not tamper with system configuration so as to circumvent the security controls and rules.
[0035] Each transaction stored in the secure system vault is assigned a globally unique ID (“GUID”) using an industry-accepted algorithm. The GUID is guaranteed to be “globally unique” (across different servers, networks or organizations). This ID can be used to uniquely identify any transaction in the secure system vault.
[0036] Each transaction stored in the secure system vault is passed through a sophisticated set of trusted algorithms for calculating a secure hash token. This hash token, which incorporates all data elements of the transaction cannot be reproduced except by the secure system itself. Any unauthorized changes to the transaction data will result in an invalidated secure token which can be easily verified. Conversely, any transaction resident in the secure system vault that has a valid secure token (i.e., one which matches the transaction data) is guaranteed to not have been modified since the secure token was generated. In this way, the integrity of each individual transaction and its constituent data can be verified.
[0037] Since the secure transaction token (“STT”) can only be generated by the system itself, any transaction that is in the secure system vault and verified is guaranteed to be valid, including all of its constituent data. This includes the User ID of the creator of the transaction. This ensures that the User ID associated with the transaction is the User ID that submitted the transaction.
[0038] Should there be a need to cancel or modify an existing transaction in the secure system vault, this action is completed as a separate and discrete event (i.e. the original transaction will never be deleted, and is simply marked as being modified or cancelled). Any such modifications or cancellations must occur prior to the designated cutoff time in order to receive the current trade date (otherwise, the new transaction gets trade-dated for the next available business day).
[0039] Each transaction creation and deletion is logged securely. The audit trail itself is tamper-resistant using the same mechanism that protects transactions stored in the vault.
[0040] Thus, it should be understood that the embodiments and examples have been chosen and described in order to best illustrate the principals of the invention and its practical applications to thereby enable one of ordinary skill in the art to best utilize the invention in various embodiments and with various modifications as are suited for particular uses contemplated. Even though specific embodiments of this invention have been described, they are not to be taken as exhaustive. There are several variations that will be apparent to those skilled in the art. Accordingly, it is intended that the scope of the invention be defined by the claims appended hereto. | A system and method for providing for the secure and protected processing of securities transactions, particularly preventing the alteration or deletion of trades in violation of the SEC rules. A secure relational database stores, protects and verifies information regarding submitted securities transactions. As transactions are created during normal business processing, they are passed through a computer system, either using real-time or batch interfaces. All transactions stored in the vault are time-stamped, encrypted and tagged for later validation. By using sophisticated, industry-accepted methods for tagging and protecting the integrity of the data, the invention ensures the integrity of each transaction and that system rule have been enforced and applied consistently. The system can be implemented in conjunction with a variety of recordkeeping systems and proprietary platforms, including but not limited to SunGard's OmniPlus system, Relius, TrustMark WyStar and proprietary platforms. | 6 |
APPLICATION DATA
[0001] This application is a divisional application of U.S. application Ser. No. 11/284,836 filed Nov. 22, 2005 which claims priority to German application DE 10 2004 058 337 filed Dec. 2, 2004, both of which are incorporated herein in their entirety by reference.
[0002] The invention relates to a process for preparing fused piperazin-2-one derivatives of general formula (I)
wherein the groups R 1 to R 5 have the meanings given in the claims and specification, particularly a process for preparing 7,8-dihydro-5H-pteridin-6-one derivatives.
BACKGROUND TO THE INVENTION
[0003] Pteridinone derivatives are known from the prior art as active substances with an antiproliferative activity. WO 03/020722 describes the use of dihydropteridinone derivatives for the treatment of tumoral diseases and processes for preparing them.
[0004] 7,8-Dihydro-5H-pteridin-6-one derivatives of formula (I) are important intermediate products in the synthesis of these active substances. Up till now they have been prepared using methods involving reduction of nitro compounds of formula (II) below, which led to strongly coloured product mixtures and required laborious working up and purification processes.
[0005] WO 96/36597 describes the catalytic hydrogenation of nitro compounds using noble metal catalysts with the addition of a vanadium compound, while disclosing as end products free amines, but no lactams.
[0006] The aim of the present invention is to provide an improved process for preparing compounds of formula (I), particularly 7,8-dihydro-5H-pteridin-6-one derivatives.
DETAILED DESCRIPTION OF THE INVENTION
[0007] The present invention solves the problem outlined above by the method of synthesising compounds of formula (I) described hereinafter.
[0008] The invention thus relates to a process for preparing compounds of general formula I
wherein
R 1 denotes a group selected from the group consisting of chlorine, fluorine, bromine, methanesulphonyl, ethanesulphonyl, trifluoromethanesulphonyl, para-toluenesulphonyl, CH 3 S(═O)— and phenylS(═O)— R 2 denotes hydrogen or C 1 -C 3 -alkyl, R 3 denotes hydrogen or a group selected from the group consisting of optionally substituted C 1 -C 12 -alkyl, C 2 -C 12 -alkenyl, C 2 -C 12 -alkynyl and C 6 -C 14 -aryl, or a group selected from the group consisting of optionally substituted and/or bridged C 3 -C 12 -cycloalkyl, C 3 -C 12 -cycloalkenyl, C 7 -C 12 -polycycloalkyl, C 7 -C 12 -polycycloalkenyl, C 5 -C 12 -spirocycloalkyl and saturated or unsaturated C 3 -C 12 -heterocycloalkyl, which contains 1 to 2 heteroatoms, R 4 , R 5 which may be identical or different denote hydrogen or optionally substituted C 1 -C 6 -alkyl, or R 4 and R 5 together denote a 2- to 5-membered alkyl bridge which may contain 1 to 2 heteroatoms, or R 4 and R 3 or R 5 and R 3 together denote a saturated or unsaturated C 3 -C 4 -alkyl bridge, which may optionally contain 1 heteroatom, and A 1 and A 2 which may be identical or different represent —CH═ or —N═, preferably —N═,
in which a compound of formula II
wherein
R 1 -R 5 and A 1 , A 2 have the stated meaning and R 6 denotes C 1 -C 4 -alkyl, a) is hydrogenated with hydrogen in the presence of a hydrogenation catalyst and b) a copper, iron or vanadium compound is added,
in which steps a) and b) may take place simultaneously or successively.
[0020] In a preferred process, the hydrogenation of the compound of formula II is carried out directly in the presence of the hydrogenation catalyst and the copper, iron or vanadium compound to form the compound of formula I.
[0021] In a particularly preferred process, after the first hydrogenation step a), first of all the intermediate product of formula III is obtained, which may optionally be isolated,
and is then further reduced in the presence of a hydrogenation catalyst and a copper, iron or vanadium compound to form a compound of formula I
[0022] Also preferred is a process in which the hydrogenation catalyst is selected from the group consisting of rhodium, ruthenium, iridium, platinum, palladium and nickel, preferably platinum, palladium and Raney nickel. Platinum is particularly preferred. Platinum may be used in metallic form or oxidised form as platinum oxide on carriers such as e.g. activated charcoal, silicon dioxide, aluminium oxide, calcium carbonate, calcium phosphate, calcium sulphate, barium sulphate, titanium dioxide, magnesium oxide, iron oxide, lead oxide, lead sulphate or lead carbonate and optionally additionally doped with sulphur or lead. The preferred carrier material is activated charcoal, silicon dioxide or aluminium oxide.
[0023] Preferred copper compounds are compounds in which copper assumes oxidation states I or II, for example the halides of copper such as e.g. CuCl, CuCl 2 , CuBr, CuBr 2 , CuI or CuSO 4 . Preferred iron compounds are compounds wherein iron assumes oxidation states II or III, for example the halides of iron such as e.g. FeCl 2 , FeCl 3 , FeBr 2 , FeBr 3 , FeF 2 or other iron compounds such as e.g. FeSO 4 , FePO 4 or Fe(acac) 2 .
[0024] Preferred vanadium compounds are compounds wherein vanadium assumes the oxidation states 0, II, III, IV or V, for example inorganic or organic compounds or complexes such as e.g. V 2 O 3 , V 2 O 5 , V 2 O 4 , Na 4 VO 4 , NaVO 3 , NH 4 VO 3 , VOCl 2 , VOCl 3 , VOSO 4 , VCl 2 , VCl 3 , vanadium oxobis(1-phenyl-1,3-butanedionate), vanadium oxotriisopropoxide, vanadium(III)acetylacetonate [V(acac) 3 ] or vanadium(IV)oxyacetylacetonate [VO(acac) 2 ]. Vanadium(IV)oxyacetylacetonate [VO(acac) 2 ] is particularly preferred
[0025] The copper, iron or vanadium compound may be used either directly at the start of the hydrogenation or after the formation of the intermediate of formula (III), as preferred.
[0026] Also preferred is a process wherein the amount of added hydrogenation catalyst is between 0.1 and 10 wt.-% based on the compound of formula (II) used.
[0027] Also preferred is a process wherein the amount of copper, iron or vanadium compound used is between 0.01 and 10 wt.-% based on the compound of formula (II) used.
[0028] Also preferred is a process wherein the reaction is carried out in a solvent selected from the group consisting of dipolar, aprotic solvents, for example dimethylformamide, dimethylacetamide, N-methylpyrrolidinone, dimethylsulphoxide or sulpholane; alcohols, for example methanol, ethanol, 1-propanol, 2-propanol, the various isomeric alcohols of butane and pentane; ethers, for example diethyl ether, methyl-tert.-butylether, tetrahydrofuran, 2-methyltetrahydrofuran, dioxane or dimethoxyethane; esters, for example ethyl acetate, 2-propylacetate or 1-butylacetate; ketones, for example acetone, methylethylketone or methylisobutylketone; carboxylic acids, for example acetic acid; apolar solvents, for example toluene, xylene, cyclohexane or methylcyclohexane, as well as acetonitrile, methylene chloride and water. The solvents may also be used as mixtures.
[0029] Also preferred is a process wherein the reaction temperature is between 0° C. and 150° C., preferably between 20° C. and 100° C.
[0030] Also preferred is a process wherein the hydrogen pressure is 1 bar to 100 bar.
[0031] The invention further relates to a compound of formula (III)
wherein R 1 to R 5 may have the stated meaning.
[0032] Preferred compounds of formula (III) are those wherein A 1 and A 2 are identical and denote —N═.
[0033] The reactions are worked up by conventional methods e.g. by extractive purification steps or precipitation and crystallisation methods.
[0034] The compounds according to the invention may be present in the form of the individual optical isomers, mixtures of the individual enantiomers, diastereomers or racemates, in the form of the tautomers as well as in the form of the free bases or the corresponding acid addition salts with acids—such as for example acid addition salts with hydrohalic acids, for example hydrochloric or hydrobromic acid, or organic acids, such as for example oxalic, fumaric, diglycolic or methanesulphonic acid.
[0035] Examples of alkyl groups, including those which are part of other groups, are branched and unbranched alkyl groups with 1 to 12 carbon atoms, preferably 1-6, particularly preferably 1-4 carbon atoms, such as for example: methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl and dodecyl. Unless otherwise stated, the above-mentioned designations propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl and dodecyl include all the possible isomeric forms. For example the term propyl includes the two isomeric groups n-propyl and iso-propyl, the term butyl includes n-butyl, iso-butyl, sec. butyl and tert.-butyl, the term pentyl includes isopentyl, neopentyl etc.
[0036] In the above-mentioned alkyl groups one or more hydrogen atoms may optionally be replaced by other groups. For example these alkyl groups may be substituted by fluorine. It is also possible for all the hydrogen atoms of the alkyl group to be replaced.
[0037] Examples of alkyl bridges, unless otherwise stated, are branched and unbranched alkyl groups with 2 to 5 carbon atoms, for example ethylene, propylene, isopropylene, n-butylene, iso-butyl, sec. butyl and tert.-butyl etc. bridges. Particularly preferred are ethylene, propylene and butylene bridges. In the above-mentioned alkyl bridges 1 to 2 C atoms may optionally be replaced by one or more heteroatoms selected from among oxygen, nitrogen or sulphur.
[0038] Examples of alkenyl groups (including those which are part of other groups) are branched and unbranched alkylene groups with 2 to 12 carbon atoms, preferably 2-6 carbon atoms, particularly preferably 2-3 carbon atoms, provided that they have at least one double bond. The following are mentioned by way of example: ethenyl, propenyl, butenyl, pentenyl etc. Unless otherwise stated, the above-mentioned designations propenyl, butenyl etc. include all the possible isomeric forms. For example the term butenyl includes 1-butenyl, 2-butenyl, 3-butenyl, 1-methyl-1-propenyl, 1-methyl-2-propenyl, 2-methyl-1-propenyl, 2-methyl-2-propenyl and 1-ethyl-1-ethenyl.
[0039] In the above-mentioned alkenyl groups, unless otherwise described, one or more hydrogen atoms may optionally be replaced by other groups. For example these alkyl groups may be substituted by the halogen atom fluorine. It is also possible for all the hydrogen atoms of the alkenyl group to be replaced.
[0040] Examples of alkynyl groups (including those which are part of other groups) are branched and unbranched alkynyl groups with 2 to 12 carbon atoms, provided that they have at least one triple bond, for example ethynyl, propargyl, butynyl, pentynyl, hexynyl etc., preferably ethynyl or propynyl.
[0041] In the above-mentioned alkynyl groups, unless otherwise described, one or more hydrogen atoms may optionally be replaced by other groups. For example these alkyl groups may be fluorosubstituted. It is also possible for all the hydrogen atoms of the alkynyl group to be replaced.
[0042] The term aryl denotes an aromatic ring system with 6 to 14 carbon atoms, preferably 6 or 10 carbon atoms, preferably phenyl, which, unless otherwise described, may for example carry one or more of the following substituents: OH, NO 2 , CN, OMe, —OCHF 2 , —OCF 3 , halogen, preferably fluorine or chlorine, C 1 -C 10 -alkyl, preferably C 1 -C 5 -alkyl, preferably C 1 -C 3 -alkyl, particularly preferably methyl or ethyl, —O—C 1 -C 3 -alkyl, preferably —O-methyl or —O-ethyl, —COOH, —COO—C 1 -C 4 -alkyl, preferably —O-methyl or —O-ethyl, —CONH 2 .
[0043] Examples of cycloalkyl groups are cycloalkyl groups with 3-12 carbon atoms, for example cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl or cyclooctyl, preferably cyclopropyl, cyclopentyl or cyclohexyl, while each of the above-mentioned cycloalkyl groups may optionally also carry one or more substituents, for example: OH, NO 2 , CN, OMe, —OCHF 2 , —OCF 3 or halogen, preferably fluorine or chlorine, C 1 -C 10 -alkyl, preferably C 1 -C 5 -alkyl, preferably C 1 -C 3 -alkyl, particularly preferably methyl or ethyl, —O—C 1 -C 3 -alkyl, preferably —O-methyl or —O-ethyl, —COOH, —COO—C 1 -C 4 -alkyl, preferably —COO-methyl or —COO-ethyl or —CONH 2 . Particularly preferred substituents of the cycloalkyl groups are ═O, OH, methyl or F.
[0044] Examples of cycloalkenyl groups are cycloalkyl groups with 3-12 carbon atoms, which have at least one double bond, for example cyclopropenyl, cyclobutenyl, cyclopentenyl, cyclohexenyl or cycloheptenyl, preferably cyclopropenyl, cyclopentenyl or cyclohexenyl, while each of the above-mentioned cycloalkenyl groups may optionally also carry one or more substituents.
[0045] “═O” denotes an oxygen atom linked by a double bond.
[0046] Examples of heterocycloalkyl groups are, unless otherwise described in the definitions, 3- to 12-membered, preferably 5-, 6- or 7-membered, saturated or unsaturated heterocycles, which may contain nitrogen, oxygen or sulphur as heteroatoms, for example tetrahydrofuran, tetrahydrofuranone, γ-butyrolactone, α-pyran, γ-pyran, dioxolane, tetrahydropyran, dioxane, dihydrothiophene, thiolane, dithiolane, pyrroline, pyrrolidine, pyrazoline, pyrazolidine, imidazoline, imidazolidine, tetrazole, piperidine, pyridazine, pyrimidine, pyrazine, piperazine, triazine, tetrazine, morpholine, thiomorpholine, diazepan, oxazine, tetrahydro-oxazinyl, isothiazole and pyrazolidine, preferably morpholine, pyrrolidine, piperidine or piperazine, while the heterocycle may optionally carry substituents, for example C 1 -C 4 -alkyl, preferably methyl, ethyl or propyl.
[0047] Examples of polycycloalkyl groups are optionally substituted, bi-, tri-, tetra- or pentacyclic cycloalkyl groups, for example pinane, 2,2,2-octane, 2,2,1-heptane or adamantane. Examples of polycycloalkenyl groups are optionally bridged and/or substituted, 8-membered bi-, tri-, tetra- or pentacyclic cycloalkenyl groups, preferably bicycloalkenyl or tricycloalkenyl groups, if they contain at least one double bond, for example norbornene.
[0048] Examples of spiroalkyl groups are optionally substituted spirocyclic C 5 -C 12 alkyl groups.
[0049] Halogen generally denotes fluorine, chlorine, bromine or iodine, preferably fluorine, chlorine or bromine, particularly preferably chlorine.
[0050] The substituent R 1 may represent a group selected from the group consisting of chlorine, fluorine, bromine, methanesulphonyl, ethanesulphonyl, trifluoromethanesulphonyl and para-toluenesulphonyl, preferably chlorine.
[0051] The substituent R 2 may represent hydrogen or C 1 -C 3 -alkyl, preferably hydrogen.
[0052] The substituent R 3 may represent hydrogen,
or a group selected from the group consisting of optionally substituted C 1 -C 12 -alkyl, C 2 -C 12 -alkenyl, C 2 -C 12 -alkynyl, and C 6 -C 14 -aryl, preferably phenyl, or a group selected from the group consisting of optionally substituted and/or bridged C 3 -C 12 -cycloalkyl, preferably cyclopentyl, C 3 -C 12 -cycloalkenyl, C 7 -C 12 -polycycloalkyl, C 7 -C 12 -polycycloalkenyl, C 5 -C 12 -spirocycloalkyl and saturated or unsaturated C 3 -C 12 -heterocycloalkyl, which contains 1 to 2 heteroatoms.
[0054] The substituents R 4 , R 5 may be identical or different and may represent hydrogen,
or optionally substituted C 1 -C 6 -alkyl, or R 4 and R 5 together represent a 2- to 5-membered alkyl bridge which may contain 1 to 2 heteroatoms, or R 4 and R 3 or R 5 and R 3 together represent a saturated or unsaturated C 3 -C 4 -alkyl bridge, which may optionally contain 1 heteroatom.
[0058] A 1 and A 2 which may be identical or different represent —CH═ or —N═, preferably —N═.
[0059] R 6 may represent a C 1 -C 4 -alkyl, preferably methyl or ethyl.
[0060] The compound of formula (II) may be prepared according to methods known from the literature, for example analogously to the syntheses described in WO 03/020722.
[0061] The compounds of general formula (I) may be prepared inter alia analogously to the following examples of synthesis. These Examples are, however, intended only as examples of procedures to illustrate the invention, without restricting it to their content. The general synthesis is shown in Scheme (1).
Synthesis of (7R)-2-chloro-8-cyclopentyl-7-ethyl-5-hydroxy-7,8-dihydro-5H-pteridin-6-one
[0062]
[0063] 30 g (84.2 mmol) of 1 are dissolved in 300 ml of tetrahydrofuran and 3 g Pt/C (5%) are added. The reaction mixture is hydrogenated for 5 h at 35° C. and a hydrogen pressure of 4 bar. The catalyst is filtered off and washed with approx. 30 ml of tetrahydrofuran. The filtrate is concentrated by evaporation under reduced pressure. 25.6 g of product 2 are obtained as a yellow solid.
[0064] 1 H-NMR (400 MHZ) (DMSOd 6 ): δ 11.05 (bs 1H); 7.85 (s 1H); 4.47-4.45 (dd 1H); 4.16-4.08 (t 1H); 1.95-1.67 (m 10H); 0.80-0.73 (t 3H)
Synthesis of (7R)-2-chloro-8-cyclopentyl-7-ethyl-7,8-dihydro-5H-pteridin-6-one
[0065]
[0066] 5.22 g (17.6 mmol) of 2 are dissolved in 55 ml of tetrahydrofuran. 520 mg Pt—C (5%) and 250 mg vanadium(IV)oxyacetylacetonate are added. The reaction mixture is hydrogenated for 6 hours at 20° C. and a hydrogen pressure of 4 bar. The catalyst is filtered off and washed with approx. 15 ml of tetrahydrofuran. The filtrate is concentrated by evaporation under reduced pressure.
[0067] 5.0 g of product 3 are obtained as a yellow powder.
[0068] 1 H-NMR (400 MHz) (DMSOd 6 ): δ 11.82 (bs 1H); 7.57 (s 1H); 4.24-4.21 (dd 1H); 4.17-4.08 (m 1H); 1.97-1.48 (m 10H); 0.80-0.77 (t 3H).
Synthesis of: (7R)-2-chloro-8-cyclopentyl-7-ethyl-7,8-dihydro-5H-pteridin-6-one
[0069] 70 g Pt/C (5%) are added to a solution of 700 g (1.96 mol) of 1 in 700 ml of tetrahydrofuran. The reaction mixture is hydrogenated for 2.5 hours at 35° C. and a hydrogen pressure of 4 bar until the hydrogen uptake has stopped. The autoclave is opened and 35 g vanadium(IV)oxyacetylacetonate are added. The mixture is hydrogenated for a further 2.5 hours at 35° C. and a hydrogen pressure of 4 bar. It is filtered and the residue is washed with tetrahydrofuran. The filtrate is concentrated by evaporation under reduced pressure. The residue is dissolved in 2.75 L acetone and precipitated by the addition of an equal amount of demineralised water. The solid is suction filtered and washed with an acetone/water mixture (1:1), then with tert.-butylmethylether. After drying 551 g of product 3 are obtained.
Synthesis of: (7R)-2-chloro-8-cyclopentyl-7-ethyl-7,8-dihydro-5H-pteridin-6-one
[0070] 30 g (84 mmol) of 1 are dissolved in 300 ml of tetrahydrofuran. 3 g Pt/C (5%) and 1.5 g vanadium(IV)oxyacetylacetonate are added. The reaction mixture is hydrogenated for 24 hours at 35° C. and a hydrogen pressure of 4 bar until the reaction is complete. It is filtered, the residue is washed with tetrahydrofuran and the filtrate is concentrated by evaporation under reduced pressure. The residue is dissolved in 118 ml acetone and precipitated by the addition of an equal amount of demineralised water. The solid is suction filtered and washed with an acetone/water mixture (1:1) and then with tert.-butylmethylether. After drying 18 g of product 3 are obtained.
Synthesis of: (7R)-2-chloro-7-ethyl-8-isopropyl-7,8-dihydro-5H-pteridin-6-one
[0071]
[0072] 10 g (316 mmol) of 4 are dissolved in 800 ml of tetrahydrofuran and 200 ml isopropanol. 10 g Pt/C (5%) and 5 g vanadium(IV)oxyacetylacetonate are added. The reaction mixture is hydrogenated for 24 hours at 35° C. and a hydrogen pressure of 4 bar until the reaction is complete. It is filtered and the filtrate is evaporated down until crystallisation sets in. 150 ml isopropanol are added and the suspension is heated to 70-80° C. until fully dissolved. After the addition of 600 ml demineralised water the product is brought to crystallisation. It is suction filtered and washed with demineralised water. After drying 68 g of product 5 are obtained.
[0073] 1 H-NMR (400 MHz) (DMSOd 6 ): δ 10.81 (bs 1H); 7.56 (s 1H); 4.37-4.24 (m 2H); 1.89-1.65 (m 2H); 1.34-1.31 (m 6H); 0.80-0.73 (t 3H) | Disclosed are processes for the preparation of fused piperazin-2-one derivatives of general formula (I)
wherein the groups R 1 to R 5 , A 1 and A 2 have the meanings given in the claims and in the description, particularly the preparation of 7,8-dihydro-5H-pteridin-6-one derivatives and intermediates thereof. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a heat pump control and more particularly to a control system for coordinately regulating the defrost operation of a dual compressor heat pump system.
2. Description of the Prior Art
The utilization of a dual compressor heat pump is advantageous for being able to independently stage the compressors to control the energy input required for necessary cooling and heating operations. The term heat pump as used herein refers to a reversible refrigeration system capable of delivering on demand either heating or cooling to a region to be conditioned. In most smaller heat pump systems, a single compressor is employed. Control of these single compressor systems is relatively simple and presents few problems. However, in many larger heat pump systems two compressors are utilized with each compressor arranged to pump refrigerant through an associated closed loop circuit.
In heat pump systems using two compressors, it is the common practice to stage the operation of compressors when the heat pump is in the cooling mode of operation whereby the compressors are brought into operation in sequence as the cooling load of the system increases. However, both compressors are normally operated when the system is providing heating to the air conditioned region without regard to the heating demands placed on the system. The operation of both of the compressors in the heating mode is carried out primarily to prevent an inadvertent cycling load on the compressors when the system is undergoing a defrost cycle. As is well known in the art starting one of the compressors when the outdoor fan is off as is typical during defrost will force the system to operate under adverse conditions which could damage the system.
The continuous operation of both compressors to avoid the problems associated with defrosting, however, gives rise to other problems which, although not as dramatic, can also lead to needless wasting of energy and eventual failure of the system. In United States patent application, Ser. No. 739,398, now abandoned entitled, "Two Stage Compressor Heating" assigned to the assignee hereof and having the same inventors as herein, there is disclosed a heat pump control system for staging the operation of the dual compressor system in the heating mode of operation. Therein is shown an electrical circuit involving a defrost system wherein one compressor or two compressors may be operated to meet the heating load as sensed by a thermostat. Therein it is disclosed that when defrost is necessary both outdoor heat exchangers will be simultaneously defrosted. By averaging the refrigerant temperatures in each system the necessity of defrost is determined. If only one compressor is in operation, then the other compressor will be energized such that both operate in a cooling mode when defrost is required.
The present system concerns itself with the staged operation of a dual compressor system in the heating mode of operation as well as independent defrost of the separate outdoor heat exchangers. The electrical control circuit provided energizes the second compressor when the first compressor is in a defrost cycle such that heating is supplied to the region to be conditioned notwithstanding that the second compressor is operated in the cooling mode to defrost the outdoor heat exchanger. Furthermore, individual relay contacts are provided in each defrost system such that if either of the compressors is being operated in a defrost cycle, the other compressor may not commence its defrost cycle. Consequently, in the heating mode of operation one compressor is always supplying heat to the enclosure or region to be conditioned notwithstanding the mode of operation of the other compressor.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a heat pump control for a multiple compressor heat pump system.
It is a further object of the present invention to provide a control system such that the heat pumps may be independently staged in the heating mode of operation.
It is a further object of the present invention to provide a multiple compressor heat pump unit wherein the operation of each compressor is regulated such that only one compressor may be in the defrost mode of operation at any one time.
It is a yet further object of the present invention to reduce the amount of energy consumed by heat pump units employing multiple compressors.
It is a still further object of the present invention to provide a dual compressor heat pump system wherein the second compressor is activated to supply heating to the area to be conditioned notwithstanding the loading conditions when the first compressor is in a defrost mode of operation.
It is another object of the present invention to operate both compressors of a dual heat pump system upon an initial heating demand when the outdoor ambient temperature is below a predetermined level.
It is a yet further object of the present invention to provide a reliable, economical and durable control system for regulating a multiple compressor heat pump system.
These and other objects will be apparent from the description to follow and the appended claims.
The preceding objects are achieved according to the present invention by the provision of a heat pump system having first and second compressors, a first indoor heat exchanger and a second indoor heat exchanger, said heat exchanger being utilized to provide heating and cooling to a conditioned region. First and second outdoor heat exchangers are operatively connected to the appropriate compressor and indoor heat exchanger to form a closed fluid refrigeration circuit. First and second defrost means for removing accumulated ice from the outdoor heat exchangers, thermostat means for activating the compressors at the appropriate temperature levels and a first control circuit which when energized activates the first defrost means to initiate a defrost cycle for the first outdoor heat exchanger operatively connected to the first compressor and which overrides the thermostat to effect starting of the second compressor regardless of the temperature within the conditioned region; and a second defrost control circuit which when energized activates the second defrost means to initiate a defrost cycle for the second outdoor heat exchanger operatively connected to the second compressor are further provided. A first defrost relay set of normally closed contacts connected to the first defrost control circuit to prevent initiation of a defrost cycle when the second defrost control circuit is in a defrost cycle, and a second defrost relay set of contacts in a normally closed position connected to the second defrost control circuit to prevent the initiation of a defrost cycle when the first defrost circuit is in a defrost cycle are utilized. Relay circuits are further provided to de-energize the reversing valves and appropriate outdoor heat exchanger fans when the unit is operated in the defrost mode of operation. An outdoor thermostat connected to a heating relay is further provided such that when the ambient temperature level is below a predetermined point all compressors are operated simultaneously at the appropriate indoor temperature level. Supplementary heat is thereafter initiated upon a further change in indoor temperature level.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic representation of a heat pump unit employing two compressors, two indoor heat exchangers and two outdoor exchangers.
FIG. 2 is an electrical diagram of illustrating circuit means for regulating the operation of the compressors utilized in the heat pump system shown in FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The embodiment as described below is particularly adapted for use with a dual compressor heat pump system. It is within the spirit and scope of this invention that the description to follow would apply to all types of multiple compressor heat pumps utilizing independent defrost cycles for separate outdoor heat exchangers associated therewith. The size, load requirements and end use of individual heat pump systems will not affect the scope of the invention as hereinafter described.
Referring to the drawings it can be seen in FIG. 1 that compressor 19 is connected through reversing valve 21 to indoor heat exchanger 17 and outdoor heat exchanger 13. It can also be seen that compressor 20 is connected through reversing valve 23 to indoor heat exchanger 16 and outdoor heat exchanger 14. Expansion valves 28 and 29 are shown in the circuitry connecting the indoor and outdoor heat exchanger for each compressor.
In the cooling mode of operation the reversing valves provide for a flow of hot gaseous refrigerant to the outdoor heat exchanger wherein the gaseous refrigerant is condensed to a liquid. From the outdoor heat exchanger the condensed liquid flows is throttled through an expansion valve undergoing a decrease in pressure. The refrigerant then changes state to a vapor in the indoor heat exchanger absorbing heat from the air passing over the heat exchanger. The now gaseous refrigerant is then returned to the compressor to complete the cycle.
In the heating mode of operation the compressed gaseous refrigerant is conducted first to the indoor heat exchanger where it is condensed from a gas to a liquid giving up the heat of condensation to the region to be conditioned. From the indoor heat exchanger, the liquid refrigerant then passes through the expansion valve to the outdoor heat exchanger where it is evaporated absorbing heat from the outdoor air before it is conducted back to the compressor as a gas. Each heat pump circuit within the system operates in the same manner.
Referring now to FIG. 2, it can be seen that line voltage is supplied through L 1 and L 2 to the electrical circuit as shown. The compressor motors (usually 3 phase and being connected across three wires but shown with only one connection to keep the drawing legible) designated 1CM and 2CM are connected across the line voltage by relay contacts 1CR-1 and 2CR-1. Relay contacts 1CR-1 are connected to compressor motor 1CM, to normally closed first defrost relay contacts 1DFR-1, to normally open first defrost relay contacts 1DFR-2 and to normally closed second defrost relay contacts 2DFR-1. The 1DFR-1 relay contacts are connected to the first outdoor heat exchanger fan motor 1HFM, and to RVR-2, the normally open reversing valve relay contacts. The normally open reversing valve relay contacts are connected to 1RV, the first reversing valve. The 1DFR-2 contacts are connected to the normally open 1DT-1 and normally closed 1DT-2 defrost timer contacts. The 2DFR-1 normally closed contacts are connected to the 1DT-1 contacts and first defrost timer, 1DT. The normally closed 1DT-2 relay contacts are connected to 1DFT, the first defrost thermostat, which is connected to the first defrost relay, 1DFR.
The 2CR-1 relay contacts and the first defrost relay, 1DFR-3, contacts are both connected to the second compressor motor, 2CM, normally closed second defrost relay contacts 2DFR-2, the normally open second defrost relay contacts 2DFR-3 and the normally closed first defrost relay contacts 1DFR-4. The 2DFR-2 contacts are connected to the second outdoor heat exchanger fan motor 2HFM and to the normally open reversing valve relay, RVR-3, contacts. The RVR-3 contacts are connected to the second reversing valve, 2RV. The second defrost relay contacts 2DFR-3, are connected to the second defrost timer normally open contacts 2DT-1 and the second defrost timer normally closed contacts 2DT-2. The 1DFR-4 contacts are connected to the normally open 2DT-1 contacts and the second defrost timer, 2DT. The normally closed 2DT-2 contacts are connected to the second defrost thermostat, 2DFT, which is connected to the second defrost relay, 2DFR.
A transformer, T-1 supplies a control current to the control section of the circuit from the line section of the circuit. Within the control section of the circuit is a thermostat having a series of four switches SW-1 through SW-4. Thermostat switch SW-1 is connected to normally open reversing valve relay contacts RVR-1, normally open heating relay contacts HR-1 and first compressor relay 1CR. Normally open thermostat switch SW-2 is connected to normally open relay contacts HR-1, normally closed heating relay contacts HR-3 and second compressor relay 2CR. Normally open thermostat switch SW-4 is connected to normally closed heating relay contacts HR-3 and normally open heating relay contacts HR-2 which are connected to supplementary heat source SH, typically electric resistance heaters. Normally open thermostat switch SW-3 is connected to the reversing valve relay, RVR and the adjustable outdoor thermostat, ADT, which is connected to heating relay HR. The RVR-1 contacts are connected to the transformer T-1, normally open thermostat switch SW-1, the first compressor relay 1CR and normally open heating relay contacts HR-1.
During operation, the first thermostat switch SW-1 is closed upon sensing a cooling need and the first compressor relay 1CR is energized activating the first compressor motor, when an additional cooling need is sensed switch SW-2 is closed and relay 2CR is energized activating the second compressor motor. During cooling operation defrost is not necessary and consequently the remainder of the circuitry is not utilized.
In the heating mode of operation, switch SW-3 is closed upon a heating need being sensed which energizes reversing valve relay and closes the appropriate reversing valve relay contacts. RVR-1 contacts close energizing the first compressor relay which consequently energizes the first compressor motor. RVR-2 is also energized by the reversing valve relay such that the first reversing valve is energized and the first compressor system operates in the heating mode of operation. During operation, the first defrost timer is energized through the 2DFR-1 normally closed contacts. Upon a predetermined elapsed period the first defrost timer closes 1DT-1 contacts and allows the 1DT-2 contacts to remain closed for a selected defrost period such as 10 minutes. If the first defrost thermostat 1DFT senses a need for defrost, by ascertaining the refrigerant temperature or utilizing some other means to detect an ice accumulation on the outside coil, the first defrost thermostat will then close and consequently during the period when both 1DT-1 and 1DT-2 are closed the first defrost relay will be energized. Once the first defrost relay is energized the 1DFR-1 contacts open discontinuing operation of the first outdoor heat exchanger fan motor and de-energizing the first reversing valve such that the system will be operated in the cooling mode of operation supplying heat to the outdoor coil. The first defrost relay-2, contacts, 1DFR-2 will be closed such that a current path is provided to continually energize the first defrost relay until such time as the defrost thermostat senses a no ice condition and opens. At that time, the first defrost relay will be de-energized and the first defrost relay-2 contacts will open thereby terminating defrost operation until such time as the defrost timer initiates another sequence to ascertain if the defrost thermostat is closed. The 2DFR-1 normally closed relay contacts are provided such that the first defrost timer cannot be activated if the second defrost relay, the defrost relay in the second compressor circuit, is energized indicating that the second circuit is in the defrost cycle. Defrost will also be terminated upon the expiration of the delay period such that the defrost timer opens the 1DFT-2 contacts deenergizing the first defrost relay.
The operation of the second compressor circuit is similar to that of the first. Upon an additional heating need being sensed, SW-4 closes energizing through the closed HR-3 contacts the second compressor relay. Consequently, the 2CR-1 contacts are closed which energizes the second compressor motor. The second compressor motor may also be energized through the 1DFR-3 contacts. When the first compressor is being operated in the defrost mode of operation, the first defrost relay will operate to close the 1DFR-3 contacts and consequently the second compressor motor will be operated such that heating will be supplied to the indoor coil from the second compressor notwithstanding the operation of the first compressor motor in the cooling mode of operation for defrost purposes. When either the 2CR-1 or the 1DFR-3 contacts are energized, the second outdoor heat exchanger fan motor 2HFM will be energized through normally closed contacts 2DFR-2. The second reversing valve will be energized through the normally closed contacts 2DFR-2 and the closed reversing valve relay contacts RVR-3. The second defrost timer will be energized through normally closed first defrost relay-4 contacts such that upon the expiration of a predetermined period the 2DT-1 contacts will be closed for a predetermined period while the 2DT-2 contacts remain in a closed position. The 2DT-1 contacts will remain closed for approximately 10 seconds after the second defrost timer is tripped during which time if the second defrost thermostat is closed, the second defrost relay will be energized. When the second defrost relay is energized the 2DFR-2 contacts are opened thereby de-energizing the second reversing valve and the second outdoor heat exchanger fan motor. The 2DFR-3 contacts will be closed thereby providing a closed circuit through the 2DT-2 contacts and through the second defrost thermostat to continually energize the second defrost relay 2DFR. When the second defrost thermostat senses that there is no longer a need for defrost it will open thereby discontinuing operation of the second defrost relay. The 2DT-2 contacts will open after the expiration of a preset period such as 10 minutes to terminate defrost in any event. The 1DFR-4 contacts are so arranged that when the first compressor is in the defrost mode of operation, the 1DFR-4 contacts are open and consequently no current is provided to the second defrost timer such that it may not initiate a defrost cycle. These contacts serve the same purpose as the 2DFR-1 contacts in the first compressor circuit.
An adjustable outdoor thermostat AOT is provided such that system operation can be varied when the outdoor ambient temperature is below a predetermined level. When the outdoor thermostat is closed then heating relay HR is energized upon switch SW-3 being closed. Consequently the HR-1 and HR-2 contacts are closed and the HR-3 contacts opened. The now closed HR-1 contacts energize 2CR simultaneously with 1CR such that upon an initial heating demand both compressors are operated simultaneously to supply heat to the area to be conditioned. Upon a further drop in indoor temperature SW-4 is closed and the supplementary heaters, typically electric resistance heaters, are energized. The HR-3 contacts are open consequently the operation of the supplementary heat is independent of compressor operations. The net effect of the heating relay is to switch the heat pump system based on outdoor ambient temperature from staged compressor operation to staged operation between the compressors and the supplemental heaters.
An electrical control circuit has been disclosed which provides in the heating mode of operation for the staging of the compressor motors such that the first compressor may be operated alone when the heating load may be satisfied thereby and such that the second compressor may be operated when the load increases. It is further provided that the first compressor motor control circuit has means for energizing the second compressor motor when the first compressor motor is operated in defrost mode such that heat will be continually supplied to the region to be conditioned. Individual relay contacts are provided in each circuit such that the first defrost relay when energized will deactivate the second defrost relay and vice versa such that only one outdoor heat exchanger may be defrosted at any particular time.
The above invention has been disclosed with reference to a particular description herein. It is to be understood that variations and modifications can be made within the spirit and scope of the following claims. | A method and apparatus for controlling a multiple compressor heat pump system such that when the system is in the heating mode of operation the compressors are cycled individually depending upon the ambient temperature level and are individually co-ordinately operated in a defrost mode. The electrical control means disclosed provides for a second compressor being energized when the outdoor heat exchanger of a first compressor is being defrosted and the first and second contact means located within the individual defrost circuits for the first and second outdoor heat exchangers such that when the first outdoor heat exchanger is being defrosted the second outdoor heat exchanger may not commence a defrost cycle and when the second compressor is being operated in a defrost cycle a first compressor may not commence a defrost cycle. | 5 |
BACKGROUND OF THE INVENTION
This invention relates to special purpose hand tools for mobile equipment, and specifically to tools for use in the lubrication of automotive speedometer cables and the like.
Flexible cable assemblies are used in many applications in the automobile, aircraft, boating and farm equipment industries for controlling equipment or transferring power. One specific application is a speedometer cable which transfers rotational motion from a small shaft on a transmission to another shaft on a speedometer.
These cables are typically made of fine flexible rod reinforced with a wire winding and operate within an outer protective casing which performs the additional function of acting as a guide member. The cable rotates or otherwise moves within the casing and must be lubricated. If no lubrication is present, the friction created between the cable and the casing causes a binding or hopping operation of the cable and eventually the cable breaks.
The need to relubricate speedometer cables is quite common in the automotive industry, and especially with new cars produced on mass production lines with high-speed equipment and components supplied from independent suppliers which very often undergo long periods of storage before use. On many new cars the speedometer cables are very often installed with the lubrication insufficiently applied or partially dried out from a long period of storage. It is very often necessary to lubricate speedometer cables after only 10,000 miles of use.
With the modular design of automobiles and the compact assembly and sub-assembly of dashboards, engines and other portions of the automobile, it is very often quite difficult if not impossible for a mechanic to manipulate equipment under the dashboard or in the engine compartment to perform such duties as lubricating a speedometer cable. The dashboard end of a speedometer cable very often is difficult to access without substantially dismantling the dashboard and instrument package. This operation often takes more than one shop hour of labor time.
It is desirable to lubricate the speedometer cable from the transmission end thereby permitting the mechanic to break the cable loose from the transmission and force grease up the cable from that end. This process can eliminate more than one hour estimated shop time which it presently takes to dismantle the dashboard and instrument package. However, forcing grease into the transmission end of the speedometer cable does not do a sufficient lubrication job in itself as the grease is reluctant to walk up the cable and thereby the uper half of the cable is not lubricated. When excessive pressures are exerted on the grease the cable often bursts.
A number of cable lubricating tools have been provided in the prior art. These, however, have been devices which merely provide a sealed grease coupling to one end of the cable for forcing grease into that end of the cable. With such tools, the grease is able to travel only short distances along the cable.
Dannels, U.S. Pat. No. 3,268,032, provides a flexible cable lubrication tool comprising a coupling member 34 for joining a standard ball type grease fitting to the end of a flexible cable. A standard alemite grease fitting is then coupled to the ball type fitting for forcing grease into the end of the cable.
Self, U.S. Pat. No. 3,283,854, provides a cable lubricating tool which may become part of and may be permanently coupled to a cable. This lubricating tool includes a casing 21 which is fitted about a special tapered cable end structure 12. A tube 42 is fitted with a ball type grease fitting 46 for introducing grease into the casing 21 and thereby the cable from the side thereof and about the cable. The cable remains in its normal operational hook up. This lubricating tool is essentially a clamp-on device for introducing grease into a pocket through which the cable extends to provide a reservoir of grease to lubricate the cable at that point. No structure is provided by Self as part of high tool for mechanically operating the cable in any specific or intended way while applying grease.
Preszler, U.S. Pat. No. 2,515,611 provides a flexible shaft greasing fitting similar to that provided by Dannels. Preszler provides either a female or male cable end coupling housing 1 to which a ball type grease fitting 2 is attached. An alemite type grease fitting connects to the Preszler structure for forcing grease into the end of the cable casing. Preszler uses this structure for lubricating the speedometer cable at the speedometer end thereof, the upper end of the cable.
West, U.S. Pat. No. 2,178,058 provides a speedometer cable lubrication tool which lubricates the cable from the speedometer end thereof. This tool includes a housing 1 into which a speedometer cable end 27 is installed. A greasing block 12 is adjusted to clamp against the cable 27 via the screw 25 adjustment means and provide a pressure seal thereto. Greasing block 12 includes a channel 18 positioned to mate the end of the cable 27 casing. A ball type grease fitting 20 is screwed into the channel 18 which has been threaded on its end. Grease which enters the channel 18 through the fitting 20 is forced into the speedometer end of the cable 27, the upper end of the cable.
Sievenpiper, U.S. Pat. No. 2,681,711 teaches a lubricating device for lubricating the transmission end of a speedometer cable. The Sievenpiper device includes a housing which sealingly engages the transmission end of the speedometer cable by screwing onto the fitting on the transmission end of the speedometer cable. This housing is fitted at its end with a ball type grease fitting. Grease introduced through the ball type fitting travels along a narrow channel to the end of the speedometer cable and is forced into that end of the cable.
Steffen, U.S. Pat. No. 3,884,329 provides a speedometer cable lubricating device for lubricating the transmission end of a speedometer cable. This device operates similarly to the Sievenpiper device for introducing grease into that end of the cable. The Steffen apparatus includes coupling members for coupling to the transmission and of the speedometer cable and a grease fitting member connected to the coupling member.
These tools, while being able to introduce grease or lubrication into the end of a speedometer cable, and even certain ones of them being able to introduce grease into the transmission end of the speedometer cable, do not provide for an adequate lubrication of that cable as the grease is capable of being forced only a short way up the speedometer cable from its bottom end.
What is desired is a speedometer cable lubrication tool which will enable the grease to be carried up the length of the speedometer cable from its transmission end thereby greasing a substantially the entire length of the speedometer cable.
An object of the present invention is to provide a speedometer cable lubrication tool which will mate in sealing engagement with the transmission end of an automotive type speedometer cable.
A second object of the present invention is to provide this lubrication tool with a standard ball type grease fitting for introducing grease into that coupled end of the speedometer cable through the tool.
A further object of the present invention is to provide a means for rotating the speedometer cable with the tool.
A further object of the present invention is to provide this lubrication tool with the capability of rotating the end of the speedometer cable, in its normal direction of rotation, while interjecting grease under normal but not excessive pressures into the transmission end of the cable.
SUMMARY OF THE INVENTION
The objects of the present invention are realized in a speedometer cable lubrication tool. This tool attaches to the transmission end of an automatic-type speedometer cable by screwing onto the coupling at that end of the cable to provide a sealed attachment thereto.
A cylindrical housing is threaded on its outside diameter at one end for threading to the transmission coupling of the speedometer cable. This threaded end of the housing carries a tapered surface which protrudes beyond the threads and is intended to seat against the cable coupling to provide the sealing engagement.
A cylindrical bore or cavity extends the length of the housing from the threaded end on to which it opens. This cavity is accessed through the side wall of the housing by means of a ball type grease fitting. This cavity opens into the end of the cable to which the tool is coupled.
A drive shaft is positioned to ride within the cavity to protrude slightly beyond the end of the housing at the threaded end and significantly beyond the housing at the opposite end. This drive shaft is supported for rotation and carries on it sealing members. The end of the shaft at the threaded end of the housing is fitted with a coupling structure for engaging the end of the speedometer cable.
To lubricate a speedometer cable the tool is installed on the end of the speedometer cable so that a seal is created at the coupling and the shaft has engaged the speedometer cable. Following this operation an alemite grease fitting can engage the ball type grease fitting to introduce grease into the cavity. An electric motor or other rotation producing device is connected to the free end of the drive shaft, the one protruding significantly beyond the housing, and is operated to cause this shaft and the speedometer cable to rotate in the normal direction of operation of the speedometer cable. Grease introduced into the cavity of the tool under pressure fills the cavity and is forced into the speedometer cable. This grease is carried along the speedometer cable and up the cable housing by the helical configuration of the cable which is turned in its normal direction of operation causing the grease to travel along the cable and up the cable casing substantially the entire length of the cable.
DESCRIPTION OF THE DRAWINGS
The novel features and advantages of this invention will be readily understood from a reading of the following detailed description of the invention in conjunction with the attached drawings in which like numerals refer to like elements, and wherein:
FIG. 1 shows a longitudinal cross sectional view of the speedometer cable lubrication tool;
FIG. 2 shows a longitudinal cross section of the speedometer cable tool coupled to the end of a speedometer cable, this tool being another embodiment of the tool of FIG. 1; and
FIG. 3 is a longitudinal cross sectional view of another embodiment of the tool of FIG. 1.
FIG. 4 is a block representation of the lubrication tool and associated equipment connected to lubricate a speedometer cable.
FIG. 5 is an end view of the lubrication tool taken as shown in FIG. 1.
DETAILED DESCRIPTION OF THE INVENTION
A speedometer cable lubrication tool 10, FIG. 1, used in lubricating an automotive-type speedometer cable without removing the cable from its casing is provided. This device is intended to be screw attached to the transmission end of the speedometer cable in sealing engagement therewith. A hand grease gun with a standard alemite type fitting is used to inject grease or lubricant into the tool and into the end of the speedometer cable. By rotating a shaft in the tool equal to a speed of about 80 m.p.h. in a direction of normal operation of the speedometer cable, while injecting grease into the tool, grease is forced and carried up the length of the cable away from the tool by the helical configuration of the speedometer cable itself in a relatively short period of time.
The lubrication tool 10 includes a cylindrically shaped housing 11, FIG. 1, being threaded on its outside diameter at either end. The speedometer coupling end threads 13 of the housing 11 can have 18 threads per inch extending over about a distance of 5/16 of an inch. This thread pattern will enable coupling with General Motors type speedometer cables. Other threads may be used when coupling to other speedometer cables if needed.
Outboard from the coupling end threads 13 is a tapered shoulder 15 which provides sealing engagement with the speedometer cable when the tool 10 is coupled thereto and this tapered shoulder 15 which is truncated conically configured abuts the inside wall of a speedometer cable coupling.
A cylindrical cavity 17 or bore extends the entire length of the housing 11. This cavity 17 is concentric with the longitudinal center line of the housing 11 and extends entirely therethrough from the coupling end 13 on to which it opens to be circumferentially traversed by the tapered shoulder 15.
An annular shoulder 19 projects within the cylindrical cavity 17 at about mid-length, although the precise position of this shoulder 19 is not critical. This shoulder 19 provides opposed abutment faces on either side thereof which are normal to the center line of the cavity 17. The annular shoulder 19 is essentially a ring which is approximately 1/16 inch to 1/8 inch thick. The cavity 17 has a 17/32 inch inside diameter on the coupling 13 side of the shoulder 19 and a 1/2 inch on the other. Alternately, the cavity 17 can have a uniform diameter throughout its length.
The opposite end of the housing 11 from the coupling end 13 is the driving end 21 which is threaded a distance of about 1/2 inch with American standard thread at approximately 20 threads per inch. A threaded cap 23 mates with the driving end threads 21 and screws down to seal off the cavity 17 which opens onto that end 21.
A hole 25 is drilled and tapped through the wall of the cylindrical housing 11 at the coupling end 13 side of the annular shoulder 19. This hole 25 is fitted with a typical 1/8 inch ball-type grease fitting 27.
Positioned to operate within the cavity 17 and extending completely through the housing 11 is a drive shaft member 29, which is held in position by the end cap 23, and extends through a center hole in this cap 23.
Drive shaft member 29 is a 5/16 inch outside diameter shaft having an enlarged diameter section 31 at about its midlength. This enlarged diameter section 31 is slightly undersized to the inside diameter (about 1/2 inches) of the cylindrical cavity 17 but rides against the inside wall of that cavity 17 in operation. The enlarged diameter section 31 can have a uniform outside diameter or can be undercut slightly in the middle section thereof, leaving bearing surfaces at either end.
Drive shaft member 29 is inserted into the housing 11 from the drive end 21 to abut against the annular shoulder 19.
A first TEFLON washer 33 which has been fitted tightly on the coupling end of the shaft 29 to abut the enlarged diameter section 31 seats between the annular shoulder 19 on its drive side and the enlarged diameter section 31 to form a seal. Second and third TEFLON washers 35, 37 are mounted on the drive 21 end of the shaft member 29 to seat against the enlarged diameter section 31. A brass bushing 38 about 7/16 inch long seats within the cavity 17 and is held against the second and third TEFLON washers 35, 37 on the outside thereof by the end cap 23. This brass bushing 38 provides rotational support for the drive shaft member 29. The driving end 39 of the drive shaft member 29 having an outside diameter of 5/16" may be sized down or sized up for coupling to a suitable rotational drive member.
The coupling end 41 of the drive shaft member 29 has a square hole formed therein for coupling to or mating with the normally square end of a speedometer cable. This coupling end 41 is slightly chamfered and protrudes slightly beyond the tapered shoulder 15 of the housing 11. The end of a speedometer cable is fitted into this rectangular hole in the coupling end 41 of the drive shaft 29.
Lubrication tool 10, FIG. 1, may be manufactured from a number of materials each being quite suitable. It is important that the first, second and third washers 33, 35, 37 be of TEFLON or other materials suitable for sealing against grease or lubrication flow. The drive shaft member 29 with its enlarged diameter section 21, can be made of ordinary carbon steel. Cylinder housing 11, including its annular shoulder 19, can also be made of ordinary cotton steel, as can be the end cap 23. When these elements are made of steel, the bushing 38 is preferably of brass or bronze.
As an alternative, the housing 11, drive shaft member 29 with enlarged diameter section 31, and end cap 23 can be made of nylon, fiberglass or other similar material. Or they may be made of chrome steel or stainless steel. However, in mixing materials certain combinations of materials work better than others. In this regard, it is better to have steel riding against steel, or steel riding against fiberglass or nylon. It is immaterial, however, whether the housing 11 and end cap 23 are made of steel or nylon and the drive shaft 29 with its enlarged diameter 31 is made of the other material.
A second embodiment 20 of the lubrication tool is shown in FIG. 2 attached to the transmission end coupling 43 of the speedometer cable. In the fully coupled state the coupling end 41 of the drive shaft member 29 engages the actual speedometer cable 45. This second embodiment 20 differs from the first embodiment 10 only as to the driving end 21 of the structure. The driving end 21 threads and end cap 23 of FIG. 1 are eliminated and the bushing 38 is press fit into the housing 11. A set screw 36 can be used to guarantee securement of the bushing 36. It is the press fit of this bushing 38 with or without set screw 36 which holds the drive shaft member 29 and its carried first, second and third TEFLON washers 33, 35, 37 into position with the first TEFLON washer 33 sealing against the annular shoulder 29 and the second and third TEFLON washers 35, 37 sealing against the bushing 38.
A third embodiment 30 is shown in FIG. 3. Here, an essentially cylindrical housing 46 which may also be machined from steel, brass or bronze, or made of cast metal, is made of plastic, fiberglass or nylon material. The driving end 47 of this housing is formed as a continuous piece with the side walls to form a rounded end 47 to the housing 45. A cylindrical cavity 49 extends from the coupling end 51 of the housing 45 along its longitudinal center line. This cavity 49 has a uniform diameter of approximately 1/2 inch and terminates at the driving end 47 of the housing 45 in a squared-off shoulder. A small bore 53 approximately 5/16 inch in diameter extends through the domed driving end 47 of the housing along its longitudinal center line. A drive shaft member 29, similar to that of the embodiments of FIGS. 1 and 2, is positioned within the cavity 49 to have its driving end 39 extend through the small bore 53. This drive shaft member 29 includes a similar enlarged diameter section 31 which is seated against the closed end of the cavity 49 with a single fourth TEFLON washer 55 which has been positioned on the driving end of the drive shaft member 29 acting to seal the drive shaft member 29 and driving end 47 of the housing from grease seepage. Grease pressure within the cavity 49 seats the enlarged diameter section 31 and TEFLON washer 33 against the end shoulder of the cavity 49.
A 1/8 inch hole 25 has been drilled and tapped through the side wall of the housing 45 and a ball-type grease fitting 27 has been inserted therein. This hole 25 is positioned forward or toward the coupling end 51 of the housing from the enlarged diameter section 31 when this section 31 is fully seated with its TEFLON washer 55 against the dome driving end 47 of the housing 46.
The coupling end 51 of the housing 45 carries external threads 13 being American standard thread at 18 threads per inch, or other threads suitable for coupling to the proper speedometer cable coupling. A tapered shoulder 15 extends outwardly from the coupling end threads 13 as with the previous embodiments. This tapered shoulder 15 provides the sealing engagement with the mating speedometer coupling as previously discussed.
Also as previously discussed, a square hole has been formed in the coupling end 41 of the drive shaft member 29. This hole is of a size to receive a speedometer cycle 45 as in the embodiment in FIG. 2.
A helical groove spiraling in the same direction as the windings of the speedometer cable 45 seen in FIG. 3, extends along the outside of the coupling end of the drive shaft member 29. While this helical groove 57 can be eliminated, it tends to aid in feeding lubricant by causing a movement of the grease which has entered the cavity 49 (from the ball-type grease fitting 27) in the general direction of the coupling end 51 of the tool and in a helical flow pattern similar to what it undergoes once it has been introduced to the speedometer cable.
Any of the speedometer lubrication tool embodiments discussed hereinabove, as, for example, the tool 10, can be coupled to a speedometer cable 45 transmission end coupling 43 as shown in FIG. 4. A dual direction or reversing motor 59 is chucked or otherwise coupled via a coupling member 61 to the driving end of the shaft member 29. This motor has its direction switch 63 adjusted to drive the shaft 29, and thereby the speedometer cable, in its normal direction of rotation. With General Motors cars this is counter-clockwise. A speed control rheostat 65, inserted in the power line 67 to the motor 59, adjusts the voltage to the motor 59 to control the motor speeds to an equivalent of about 80 miles per hour on the vehicle speedometer. This speed control rheostat 65 may be adjusted and calibrated to actual speed seetings or the mechanical may look at the speedometer of the vehicle while the speedometer cable is being turned by the motor 59. With the speedometer cable turning at about 80 miles per hour, grease is injected into the tool 10 via the grease fitting 27 from a standard grease gun with alemite fitting 69. About 8 to 10 standard pumps on a hand-operated grease gun will provide a sufficient quantity of grease to the cable 45 and will, through the rotation of the cable 45, for about 30 seconds cause a traveling of this grease substantially up the entire length of the cable casing.
Many modifications can be made in the speedometer lubrication tool described above without deviating from the intent and scope thereof. Likewise, modifications can also be made in the system layout of FIG. 4 without deviating from the intent and scope thereof. It is intended, therefore, that the above description be taken as illustrative and not be interpreted in the limiting sense. | A tool for coupling to an end of an encased speedometer cable on an automobile or other motor vehicle in sealing engagement therewith for applying grease or other lubrication into that end of the speedometer cable under pressure while making rotational coupling with a drive member for rotating the cable from a protruding shaft portion of the tool for causing the lubrication to walk up the cable. | 5 |
BACKGROUND OF THE INVENTION
The present invention is generally directed to a mechanism for the retention and anchoring of electrical equipment to prevent damage to it during seismological events. More particularly, the present invention is directed to an anchoring and energy-absorbing mechanism for use with heavy electronic equipment such as mainframe computers. Even more particularly, the present invention is directed to a mechanism and method for convenient installation and removal of electrical equipment, especially mainframe computers.
Most seismological events are small and, therefore, do not have any significant influence on the operation of various kinds of electrical equipment. On the other hand, at the other end of the seismological spectrum, major damage to buildings and architectural structures including the collapse of these structures cannot be prevented nor are there reasonable approaches for protecting equipment therein when such buildings collapse. Nonetheless, there is an intermediate spectrum of seismological events wherein damage can be done to the frame and structures of relatively heavy computer equipment, especially to equipment weighing between approximately 1,000 and 2,000 pounds, or more. Such equipment typically includes relatively large server or mainframe computers.
Within this intermediate range of seismological events, it becomes possible to provide a degree of protection which serves to increase the probability that the equipment remains operational after the event. A significant step in this direction is providing a mechanism which ensures that the frame in which the electronic equipment is disposed is not bent or fractured. Damage to the frame and to the corresponding electrical connection supported by the frame becomes more likely in stronger seismological events. These seismological events can produce destructive accelerations. As a result of this acceleration and the relatively large mass associated with certain larger pieces of computer or electrical equipment, there is a correspondingly relatively high energy imparted to the equipment structure during earthquake activities. These energies must somehow be contained so as to reduce destructive relative motions of the heavy equipment assembly.
For most purposes and locations, seismological activity is not such a problem as to require anchoring or restraint mechanisms. However, in certain critical applications such as air traffic control, retention mechanisms become much more significant and highly desirable. Likewise, in locations where seismological activity is relatively high, protection of relatively expensive electrical equipment becomes more of a significant concern.
If one is attempting to restrain relatively light weight equipment, then it is possible to employ fixed or flexible restraints having multiple degrees of freedom. However, such designs do not work well for heavy equipment. The induced motion in a vertical or horizontal direction which is permitted in a multi-degree of freedom fixed restraint system can cause damage to the equipment, frame and structure. Furthermore, simple bolting mechanisms do not always work well because of the excessive load supplied to the single joint point of attachment. Similarly, mechanisms employing either free or locked casters or wheels are unacceptable in many mid-range seismological events of the magnitude considered herein. Additionally, other flexible restraint and/or fixed restraint systems have been found wanting in terms of high stress load and their inabilities to sufficiently absorb energies induced by various motions encountered during seismological events. These motions include movement in directions other than the vertical direction. It is particularly noted that during seismological events, various twisting and turning motions may be induced as a result of the motion of the underlying earth crustal plate structures and the motions of the buildings in which the equipment is deployed.
It is also important that any mechanism for anchoring or restraining relatively heavy equipment be designed so that it is convenient to use and can be installed with ease in any number of different locations. It is also highly desirable that the equipment can be easily placed, anchored and installed in the field.
SUMMARY OF THE INVENTION
In accordance with one embodiment of the present invention, heavy electrical equipment such as a mainframe computer is attached to an underlying fixed structure such as a floor by means of a sequence of eyebolts, threaded yokes and turnbuckles which connect the equipment to a fixed structure. In preferred embodiments of the present invention, the equipment is mounted in a frame structure, the bottom of which includes four triangular plates. Each of the plates has an eyebolt attached thereto by means of an arrangement of nuts and load-distributing washers. The eyebolt may also be welded to the plate. This eyebolt is disposed within the yoke portion of a threaded yoke which passes through a bushing inserted in a corresponding opening in a raised floor structure. The other end of the threaded yoke is disposed within a threaded opening of a turnbuckle. In preferred embodiments of the present invention, the other end of the turnbuckle also includes another threaded yoke which is attached thereto and has a yoke portion which receives a second eyebolt which is firmly attached to a fixed structure such as a floor, subfloor, column, girder or some other rigid portion of a building.
In one aspect of the present invention, a preferred embodiment includes a combination of the equipment and the seismological retention structure described herein. In another preferred embodiment, the present invention includes an assembly of parts, some which may be pre-assembled. Such a collection of parts may be shipped prior to computer installation. In yet another embodiment of the present invention, a method is provided for conveniently installing mainframe computer units. This method provides convenience and flexibility while retaining full anchoring, retention and energy absorption capabilities while still providing sufficient design flexibility to accommodate raised floors having different depths. It is furthermore noted that the structure of the present invention is designed in a manner in which it is possible to use as many off-the-shelf parts as possible. This makes construction and utilization of the present invention not only very easy, but also very economical.
Accordingly, it is an object of the present invention to provide a mechanism for anchoring and for restraining the movement of equipment during earthquakes and/or seismological events.
It is also an object of the present invention to provide a retention and anchoring arrangement for heavy electrical or electronic equipment including mainframe or server devices.
It is yet another object of the present invention to provide an anchoring and retention mechanism which can be installed and positioned prior to or even after initial installation of a computer system.
It is still another object of the present invention to provide a mechanism for computer installation in as rapid a time as possible while still providing a mechanism to prevent damage to computer equipment during seismological events.
It is yet another object of the present invention to provide a retention and anchoring mechanism against seismological motion.
It is a still further object of the present invention to provide an anchoring and retention mechanism which can be readily constructed from economical, off-the-shelf components.
It is also an object of the present invention to provide an anchoring and retention mechanism which is capable of absorbing relatively large amounts of seismically induced energies so as to prevent damage to the frame of the structure housing the equipment to be protected.
It is yet another object of the present invention to permit the use of wheels or casters on heavy electrical equipment without sacrificing the ability to include earthquake and/or motion retention mechanisms.
It is also an object of the present invention to provide an installation method which is flexible and convenient.
It is a still further object of the present invention to prevent damage to equipment-holding frame structures during earthquake events.
It is yet another object of the present invention to provide a field-installable mechanism for protection against seismological or other undesirable motions.
It is also an object of the present invention to provide an earthquake protection mechanism which is adaptable to different raised floor depths.
Lastly, but not limited hereto, it is an object of the present invention to prevent earthquake damage to heavy electrical or electronic equipment.
BRIEF DESCRIPTION OF THE DRAWINGS
The subject matter which is regarded as the invention is particularly pointed out and distinctly claimed in the concluding portion of the specification. The invention, however, both as to organization and method of practice, together with the further objects and advantages thereof, may best be understood by reference to the following description taken in connection with the accompanying drawings in which:
FIG. 1 is an isometric view of the underside of an equipment frame showing placement and connection for the retention and anchoring devices of the present invention;
FIG. 2 is an exploded view of an anchoring or retention apparatus in accordance with the present invention;
FIG. 3 is a detailed isometric view of the through-floor bushing employed in the present invention;
FIG. 4 is a detailed isometric view of a turnbuckle (short version) employed in the present invention to adjust the tension in the anchoring apparatus which holds the frame to a fixed structure;
FIG. 5 is a detailed isometric view of a plate which is disposed on the bottom of the frame;
FIG. 6 is a side elevation view illustrating one embodiment of the relationship between various portions of the anchoring or retention mechanism of the present invention and a subfloor and particularly illustrating the role and placement of the through-floor bushing shown in FIGS. 1, 2 and 3;
FIG. 7 is an exploded isometric view, of one embodiment of a retaining structure in accordance with the present invention, which particularly illustrates an inverted bushing and a long version of a turnbuckle;
FIG. 8 is an exploded isometric view, of one embodiment of a retaining structure in accordance with the present invention, which particularly illustrates the use of an alternate form of bushing;
FIG. 9 is an isometric view illustrating one embodiment of the present invention illustrating an alternate placement and orientation of a through-floor bushing and the use of a longer turnbuckle version;
FIG. 10 is a view similar to FIG. 7 except that it illustrates the inclusion of a shorter version of a turnbuckle;
FIG. 11 is a view similar to FIG. 8 except that it illustrates the inclusion of a shorter version of a turnbuckle; and
FIG. 12 is a view similar to FIG. 9 except that it illustrates the inclusion of a shorter version of a turnbuckle.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 illustrates the preferred placement and attachment of four devices 10 of the present invention on the bottom of frame 100 which is configured to hold various forms of electrical and/or electronic equipment. In particular, frame 100 shown in FIG. 1 is particular suited for the containment of computer systems weighing between approximately 1,000 and 2,000 pounds, or more. Retention devices 10 are attached to the bottom of frame 100 by means of plates 20 which are firmly bolted to the bottom of frame 100. Plate 20 may be provided in any convenient shape. However, in accordance with preferred embodiments of the present invention, plates 20 are triangular in shape and are preferably four in number disposed at the corners of the bottom of frame 100. In preferred embodiments of the present invention, the long edges of triangular plates 20 are affixed to the bottom of frame 100 so as to be directed towards the central area of the bottom of frame 100, as shown in FIG. 1.
One of the major advantages of the present invention is its convenience. In particular, casters 110 disposed on the bottom of frame 100 permit the apparatus to be rolled into place and quickly connected to pre-assembled portions of device 10 which extend upwards from a fixed floor through a raised floor structure. In particular, retention devices 10 are preferably put into position prior to the installation of a computer system. Once devices 10 are in place, it is a simple matter to roll frame 100 into position and to connect the frame to the floor retention assembly as shown simply by means of four pins through eyebolts as is more particularly described below in connection with FIG. 2.
FIG. 2 illustrates an earthquake retention assembly in accordance with the present invention. It is also noted that for purposes of illustration, FIG. 2 also includes plate 20. However, it is noted that reference numeral 10 does not in fact refer to an assembly which includes plate 20. Plate 20 does, nonetheless, include eyebolt 70 which is attached to a central aperture in plate 20 by means of nuts 61a and 61b. Eyebolt 70 possesses a threaded portion which extends firstly through nut 61b thence through washer 51b, plate 20, washer 51a and finally through nut 61a. Washers 51a and 51b better distribute the load applied by nuts 61b and 61a during tightening. Eyebolt 70 may also be welded to plate 20. In a typical assembly, plate 20 and attached eyebolt 70 are in position on the bottom of frame 100 prior to final computer installation. Before the final installation in which the computer is rolled into place and connected to the underlying structure via pin 90, the retention assembly of the present invention is typically already partially installed. In particular,. the present invention is installed through a subfloor (see FIGS. 6, 9 and 12) so as to ultimately attach computer equipment to a fixed structure of a building. This fixed structure (130 in FIGS. 9 and 12) is any convenient floor, beam or other rigid structure which is part of the building in which the equipment is to be installed.
In a typical installation process, eyebolt 80 is fastened to this rigid building structure by means of nuts 61c and 61d and washer 51c. Threaded eyebolt 80 also preferably includes nut 36 (or bushings 35' or 36' as shown in FIGS. 8 and 11) which is disposed within the eye of the threaded eyebolt to act as a bushing and energy-absorbing mechanism. In particular, the utilization of nuts 35 and 36 as eyebolt bushings herein serve to assist in the desire to be able to construct the apparatus of the present invention using readily available, off-the-shelf components. This not only increases availability but also decreases the economic costs of the device.
Threaded yoke 85 has a yoke portion which straddles the eye of eyebolt 80 and is affixed thereto by means of pin 95 which extends through holes in the yoke portion and also extends through the center of nut 36. Pin 95 is held in place by means of cotter pin 96 which extends through pin 95 to retain it in position and to thus hold threaded yoke 85 in position. The threaded portion of threaded yoke 85 is disposed within a threaded opening 42 of turnbuckle 40 (see FIG. 4). Turnbuckle 40 preferably includes a central opening for receipt of a lever device which may be employed to tighten the assembly and to more firmly anchor the equipment to the floor. For purposes of the present invention, a turnbuckle is any suitably sized device having oppositely disposed threaded openings which are threaded so that rotation of the turnbuckle moves threaded shafts disposed therein in opposite directions for purposes of tightening or loosening. Turnbuckles illustrated herein include short versions 40 (as shown in FIGS. 2, 4, 6, 10, 11 and 12) and long versions 40' (as shown in FIGS. 7, 8 and 9). Turnbuckles of any convenient length may also be provided. However, the two turnbuckle designs illustrated herein are sufficient to accommodate a very high percentage of raised-floor heights.
Turnbuckle 40 also includes a second threaded opening 41 at its opposite end for receipt of the threaded portion of threaded yoke 75. Threaded yoke 75 extends downwardly through a central opening in bushing 30 which preferably comprises any convenient elastomeric material. The upper surface of bushing 30 is meant to lie flush with the top of raised floor 120 as shown in FIG. 6. Thus, during a typical installation operation, threaded yoke 75 is inserted downwardly through bushing 30 which is already present in a raised floor structure. Threaded yoke 75 is then inserted by means of a threading operation into the upper threaded opening of turnbuckle 40 to a depth sufficient to place the yoke portion of threaded yoke 75 into alignment with the eye of eyebolt 70.
In preferred installation operations, as many of the anchoring mechanisms 10 as is desirable are inserted through openings in raised floor 120. As many retention devices 10 as is desired are employed. During final installation, frame 100 containing relatively heavy electrical or electronic equipment is rolled into position and aligned with the yoke portions of threaded yokes 75 which extend upwardly through raised floor 120. Final assembly is accomplished by means of insertion of pins 90 through openings in the yoke portion of threaded yoke 75 and through the center of nut 35 disposed within the eye of eyebolt 70. Cotter pin 91 is then disposed through an opening in pin 90 to hold the assembly together. At this point, turnbuckle 40 is turned so as to apply a desired level of tension to the assembly.
FIGS. 3, 4 and 5 provide more detailed views of bushing 30, turnbuckle 40 and plate 20. Likewise, FIG. 6 more particularly illustrates the disposition of threaded yoke 75 through bushing 30 disposed in raised floor 120. Also illustrated is the connection between threaded yokes 75 and 85 through turnbuckle 40.
The utilization of plate 20 in the present invention provides an important level of protection which is not provided if eyebolt 70 were to be connected directly to frame 100. If one were to perform this direct connection, it is more likely that frame 100 would be significantly damaged in an earthquake. However, by providing plate or plates 20, there results a mechanism in which energy imparted to the heavy equipment during an earthquake is absorbed by means of the bending and flexing of plate or plates 20. This provides a very high degree of energy absorption capability while at the same time maintaining the computer equipment in a relatively fixed position. Plates 20 also provide convenient positioning and placement for eyebolts 70 which are simultaneously placed into alignment with all of the desired yokes simply by rolling the cabinet and frame into place using casters 110. It is additionally noted that the structure and apparatus provided in the present invention does not simply comprise a single eyebolt such as eyebolt 80 extending upwardly from a fixed rigid subfloor. While such an arrangement is physically possible, such an arrangement would not provide the desired degree of energy absorption during a seismological (or other) event. Nor would such an apparatus provide the flexibility and alignment and height tolerances afforded by the inclusion of a device such as turnbuckle 40 which not only permits variations in initial height but also provides a mechanism for applying sufficient tension within the apparatus. Turnbuckle 40 also provides additional energy absorption capability. However, it is noted that in accordance with one variation of the present invention, threaded yoke 85 and eyebolt 80 could be replaced by a single threaded rod. However, this is not a preferred embodiment of the present invention since the inclusion of these elements adds extra energy absorption capabilities in terms of the cushioning effect of nut 36, potential bending of pin 95 and distortion of the yoke portion of threaded yoke 85. All of these structures provide some degree of energy absorption capability. Again, it is important to note that it is much preferred to have energy absorption occur in the earthquake retention device of the present invention than it is to have large amounts of energy absorbed within the frame structure. Energy transmitted in a sufficiently strong earthquake to a computer frame does have the capability of disrupting electrical connections within the frame, thus shutting down the computer system. However, as pointed out above, there are many times and many situations in which the continued operation of a computer system becomes of tantamount importance, such as in air traffic control situations or in defense systems. One wants to provide as much protection as is reasonably possible in such circumstances. However, it is well recognized that, at some level of seismological or other activity, no precaution is sufficient.
In a typical equipment installation operation, the lower eyebolts are attached to a fixed structure 130 below the raised floor which supports the equipment. A first threaded yoke is connected to the lower eyebolt and is in turn inserted into the turnbuckle. A second threaded yoke is inserted through a bushing in the subfloor into an upper threaded opening in the turnbuckle. The threaded yokes are connected to the eyebolt holes by means of devices such as clevis pins which are further retained in position by means of a conventional cotter pin or similar member disposed through a hole in the pin. The turnbuckle and upper threaded yoke are turned so as to position the upwardly extending yoke at a desired height relative to the raised floor. The yokes are then preferably aligned so as to receive the eyebolts which extend downwardly from plates 20 when the equipment is rolled into place. Final attachment pins are disposed through the upper yoke and the downwardly extending eyebolts and the turnbuckle is tightened to ensure minimal equipment motion during an earthquake or other disturbance including explosions, natural or otherwise, occurring within or around the building in which the equipment is housed. The present invention is therefore seen not to be limited to protection against purely seismological events.
Accordingly, from the above, it should be appreciated that the present invention satisfies all of the objects set forth herein. In particular, the earthquake retention apparatus of the present invention provides an economical and extremely convenient method for installing computer and/or other heavy electrical equipment in situations and locations in which there is a higher than normal risk of seismological or other activity. It is furthermore noted that the retention apparatus of the present invention provides a mechanism for providing a plurality of localized energy absorption points disposed between a computer frame which is meant to be protected and a firm anchoring point. It is further noted that the present invention satisfies the objects set forth herein in that installation can be accomplished in a convenient manner and in a similar fashion removal of the equipment is likewise readily accomplished simply by removing one or more pins.
In preferred embodiments of the present invention, it is seen that four triangular plates are employed. However, in other circumstances, particularly with smaller and/or somewhat lighter weight equipment (less than 2,000 pounds), a single square or rectangular plate centrally disposed on the bottom of the equipment frame is employable while still remaining within the scope and concept of the present invention.
While the invention has been described in detail herein in accordance with certain preferred embodiments thereof, many modifications and changes therein may be effected by those skilled in the art. Accordingly, it is intended by the appended claims to cover all such modifications and changes as fall within the true spirit and scope of the invention. | Relatively heavy electrical equipment, such as a computer mainframe or server unit, is provided with a mechanism which prevents and/or mitigates damage to the equipment caused by seismological or other activity. In particular, the mechanism comprises a turnbuckle having threaded yokes disposed at opposite ends of the turnbuckle together with eyebolts disposed within the yoke portions of the threaded yokes as a means for providing a retention device for anchoring relatively heavy computer and/or other equipment in position during seismological events. The electrical equipment is disposed within a frame which preferably includes a plurality of metal plates disposed at the bottom thereof. The frame is also provided with casters which permit the equipment to be rolled conveniently into place and then anchored firmly into position using a small number of pins which extend through the threaded yokes and eyebolts. There is provided an easily assemblable and economical apparatus which preferably includes a multiplicity of energy absorption points which help to prevent damage to the expensive computer frame and which further assists in maintaining computer operations at peak levels even during certain seismological activity. | 8 |
FIELD OF THE INVENTION
[0001] The present invention relates generally to the field of excavation and, more particularly, to a system and process for acquiring geological and positional data, and for controlling an excavator in response to the acquired data.
BACKGROUND OF THE INVENTION
[0002] Various types of excavators have been developed to excavate a predetermined site or route in accordance with a particular manner of excavation. One particular type of excavator, often referred to as a track trencher, is typically utilized when excavating long continuous trenches for purposes of installing and subsequently burying various types of pipelines and utility conduits. A land developer or contractor may wish to excavate several miles or even hundreds of miles of terrain having varying types of unknown subsurface geology.
[0003] Generally, such a contractor will perform a limited survey of a predetermined excavation site in order to assess the nature of the terrain, and the size or length of the terrain to be excavated. One or more core samples may be analyzed along a predetermined excavation route to better assess the type of soil to be excavated. Based on various types of qualitative and quantitative information, a contractor will generally prepare a cost budget that forecasts the financial resources needed to complete the excavation project. A fixed cost bid is often presented by such a contractor when bidding on an excavation contract.
[0004] It can be appreciated that insufficient, inaccurate, or misleading survey information can dramatically impact the accuracy of a budget or bid associated with a particular excavation project. An initial survey, for example, may suggest that the subsurface geology for all or most of a predetermined excavation route consists mostly of sand or loose gravel. The contractor's budget and bid will, accordingly, reflect the costs associated with excavating relatively soft subsurface soil. During excavation, however, it may instead be determined that a significant portion of the predetermined excavation route consists of relatively hard soil, such a granite, for example. The additional costs associated with excavating the undetected hard soil are typically borne by the contractor. It is generally appreciated in the excavation industry that such unforeseen costs can compromise the financial viability of a contractor's business.
[0005] Various methods have been developed to analyze subsurface geology in order to ascertain the type, nature, and structural attributes of the underlying terrain. Ground penetrating radar and infrared thermography are examples of two popular methods for detecting variations in subsurface geology. These and other non-destructive imaging analysis tools, however, suffer from a number of deficiencies that currently limit their usefulness when excavating long, continuous trenches, or when excavating relatively large sites. Further, conventional subsurface analysis tools typically only provide an image of the geology of a particular subsurface, and do not provide information regarding the structural or mechanical attributes of the underlying terrain which is critical when attempting to determine the characteristics of the soil to be excavated.
[0006] There is a need among developers and contractors who utilize excavation machinery to minimize the difficulty of determining the characteristics of subsurface geology at a predetermined excavation site. There exists a further need to increase the production efficiency of an excavator by accurately characterizing such subsurface geology. The present invention fulfills these and other needs.
SUMMARY OF THE INVENTION
[0007] The present invention is an excavator data acquisition and control system and process for characterizing the subsurface geology of an excavation site, and for utilizing the acquired data to optimize the production performance of an excavator. A geologic imaging system and a geographic positioning system are employed to initially survey a predetermined excavation site or route. A geologic characterization unit may also be employed to enhance the geologic imaging data. The acquired data are processed to provide detailed geologic and position data for the excavation site and utilized by a main control unit to optimize excavator production performance. In one embodiment, the main control unit accesses a geologic filter database, which includes geologic profile data for numerous types of geology, when analyzing unknown subsurface geology. Removing geological filter data content corresponding to known geology from the acquired geologic imaging data provides for immediate recognition of unknown and suspect subsurface objects. The geologic imaging system preferably includes a ground penetrating radar system having a plurality of antennas oriented in an orthogonal relationship to provide three-dimensional imaging of subsurface geology. Correlation software is employed to correlate acquired geologic image data to historical excavator production performance data to characterize the structural mechanics of subsurface geology. Accurate geographic mapping of an excavation site is provided by the geographic positioning system which preferably includes a mobile transponder mounted to an excavator and a plurality of ground-based transponders. In one embodiment, signals transmitted by one or more Global Positioning System (GPS) satellites are utilized together with reference signals produced by a plurality of ground-based transponders.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] [0008]FIG. 1 is a side view of one embodiment of an excavator, termed a track trencher, including a ditcher chain trenching attachment;
[0009] [0009]FIG. 2 is a generalized system block diagram of a track trencher embodiment of an excavator;
[0010] [0010]FIG. 3 is an illustration of a main user interface for controlling a track trencher excavator, for viewing acquired geological and position data, and for interfacing with various electronic and electromechanical components of the excavator;
[0011] [0011]FIG. 4 is a system block diagram of a main control unit (MCU) of a novel excavator data acquisition and control system;
[0012] [0012]FIG. 5 is a system block diagram of a geologic data acquisition unit (GDAU) of a novel excavator data acquisition and control system;
[0013] [0013]FIG. 6 is plot of reflected source electromagnetic signals received by a ground penetrating radar system using a conventional single-axis antenna system;
[0014] [0014]FIG. 7 is a system block diagram of a geographic positioning unit (GPU) of a novel excavator data acquisition and control system;
[0015] [0015]FIG. 8 is a system block diagram of an excavator control unit (ECU) of a novel excavator data acquisition and control system;
[0016] [0016]FIG. 9 is a block diagram of various databases and software accessed and processed by the main control unit (MCU);
[0017] [0017]FIG. 10 is an illustration of a predetermined excavation site having a heterogenous subsurface geology;
[0018] [0018]FIG. 11 is an illustration of a survey profile in chart form obtained for a predetermined excavation route using a novel geologic data acquisition unit (GDAU) and geologic positioning unit (GPU);
[0019] [0019]FIG. 12 is an illustration of an estimated excavation production profile in chart form corresponding to the survey profile chart of FIG. 11;
[0020] [0020]FIG. 13 is an illustration of a predetermined excavation site having a heterogenous subsurface geology and an unknown buried object;
[0021] [0021]FIG. 14 is an illustration of a conventional single-axis antenna system typically used with a ground penetrating radar system for providing two-dimensional subsurface geologic imaging;
[0022] [0022]FIG. 15 is an illustration of a novel antenna system including a plurality of antennas oriented in an orthogonal relationship for use with a ground penetrating radar system to provide three-dimensional subsurface geologic imaging;
[0023] [0023]FIG. 16 is an illustration of a partial grid of city streets and an excavator equipped with a novel excavator data acquisition and control system employed to accurately map a predetermined excavation site; and
[0024] FIGS. 17 - 20 illustrate in flow diagram form generalized method steps for effecting a novel excavator data acquisition and control process.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0025] The novel excavator data acquisition and control system and process provides for a substantial enhancement in excavation efficiency and project cost estimation by the acquisition and processing of geological, geophysical, and geographic position information for a particular excavation site. The operation of an excavator is preferably optimized by modifying excavator operating parameters based on acquired survey data and input commands received from an operator of the excavator. The accuracy of estimating the resources and costs associated with excavating a particular excavation site is significantly increased by providing a computational analysis of the acquired survey data prior to initiating excavation of the site, thereby substantially reducing a contractor's risk of misquoting the costs associated with a particular excavation project due to a lack of accurate and detailed information regarding the geology of the subject excavation site.
[0026] The advantages and features of a novel excavator data acquisition and control system and process will generally be discussed with reference to one particular type of excavator, termed a track trencher. It is to be understood, however, that a track trencher represents only one of many embodiments of an excavator that may be equipped with a novel excavator data acquisition and control system as disclosed hereinbelow. As such, the advantages and features of the disclosed novel system and process are not limited to application in connection with a track trencher.
[0027] Referring now to the figures and more particularly to FIG. 1, there is shown an illustration of one embodiment of an excavator well-suited for incorporating a novel data acquisition and control system. A track trencher excavator, shown in FIGS. 1 and 2, typically includes an engine 36 coupled to a right track drive 32 and a left track drive 34 which together comprise the tractor portion 45 of the track trencher 30 . An excavation attachment 46 , usually coupled to the front of the tractor portion 45 , typically performs a specific type of excavating operation.
[0028] A ditcher chain 50 , or other excavation attachment, is often employed to dig trenches of varying width and depth at an appreciable rate. The ditcher chain 50 generally remains above the ground in a transport configuration 56 when maneuvering the trencher 30 around an excavation site. During excavation, the ditcher chain 50 is lowered, penetrates the ground, and excavates a trench at the desired depth and speed while in a trenching configuration 58 . Another popular trenching attachment, termed a rock wheel in the art, may be controlled in a manner similar to that of the ditcher chain 50 . A track trencher 30 is well-suited for efficiently excavating a trench along a predetermined excavation route for the purpose of installing various types of pipelines and utility conduits.
[0029] In FIG. 3, there is illustrated a main user interface 101 of a track trencher 30 . Propulsion and steering of a track trencher 30 when operating in a transport mode is generally controlled by manipulating the left and right track levers 64 and 66 which respectively control actuation of the left and right track drives 34 and 32 . Moving the right track lever 66 forward, for example, generally causes the right track drive 32 to operate in a forward direction and, depending on the relative velocity of the left track drive 34 , steers the track trencher 30 to move in either a left or right direction. Reversing the right track drive 32 is generally accomplished by pulling the right track lever 66 backwards, thereby causing the right track drive 32 to operate in a reverse direction. Propulsion of the left track drive 34 is accomplished in substantially the same manner as that previously described with regard to the right track drive 32 . Thus, both propulsion and steering are generally controlled by the track levers 64 and 66 of a track trencher 30 . Alternatively, the main user interface 101 may be configured to provide for independent steering and propulsion of the left and right track drives 34 and 32 , respectively.
[0030] It is often desirable to maintain the engine 36 at a constant, optimum output level during excavation which, in turn, allows the attachment 46 to operate at an optimum excavating output level. A prior art control panel typically includes a plurality of controls and switches, including a speed range switch, RPM knob, steering trim knob, and propel trim knob, all of which must typically be adjusted during normal trenching operation to maintain the engine at the desired engine output level when encountering variable attachment 46 loading, and to steer the track trencher 30 in a desired direction. Additionally, a pair of right and left pump potentiometers typically require adjustment and readjustment to equilibrate the operational characteristics of the left and right pumps 38 and 40 .
[0031] A significant disadvantage of a conventional track trencher control panel concerns a requirement that the operator must generally react quickly to changes in engine 36 loading, typically by first determining the appropriate switch to adjust and then the degree of switch adjustment. Typically, minor propulsion modifications are made by adjusting the propel trim knob. Moderate changes to the propulsion level of the track trencher 30 are generally effected by adjusting the RPM knob. A major modification to the propulsion level of the track trencher 30 is typically accomplished by switching the speed range switch from a high setting to either a medium or low setting, and once again adjusting the propel trim knob and RPM knob in order to avoid stalling out the engine 36 .
[0032] The novel data acquisition and control system and process obviates the requirement of continuous manual adjustment and readjustment of a plurality of control switches, knobs, and levers. Instead, an intelligent excavation control unit (ECU) is employed to continuously monitor a network of sensors that transduce various excavator functions into electrical signals, and processes these and other electrical signals to optimize the steering and excavating performance of the excavator, with only minimal intervention by an excavator operator. An enhanced user-interface communicates pertinent excavator performance information, as well as geological and geographical position data, to an operator preferably over a display, such as a liquid crystal display or a cathode ray tube display, for example. A keyboard and other levers and switches are provided on the user-interface to communicate with the data acquisition and control system, and control the operation of the excavator.
[0033] Data Acquisition and Control System
[0034] Turning now to FIG. 4, there is illustrated a novel data acquisition and control system shown in system block diagram form. In broad and general terms, the system shown in FIG. 4 significantly enhances the operation of an excavator by the acquisition of geological, geophysical, and position information regarding a particular excavation site, and by employing this information to enhance excavation efficiency. The acquisition of such pertinent excavation site data substantially reduces the risk involved in estimating the cost and scheduling of a particular excavation project. Real-time acquisition of geographical position data provides for precision mapping of an excavated area to accurately identify the location and depth of, for example, buried pipelines and utility conduits installed at the excavation site. These and other significant advantages and features are provided by the novel excavator data acquisition and control system and process as discussed in greater detail hereinbelow.
[0035] Referring to FIG. 4 in greater detail, the primary processing component of the novel data acquisition and control system is a main control unit (MCU) 250 , which preferably includes a central processing unit (CPU) 264 , Random-Access-Memory (RAM) 266 , and non-volatile memory 286 , such as Electrically Erasable Programmable Read-Only-Memory (EEPROM). The MCU 250 preferably includes appropriate input and output ports to communicate with a number of other sub-systems that acquire various types of data, process such data, and interface with the control system of an excavator to moderate and optimize the excavation process. A main user interface (MUI) 101 is preferably situated in proximity to an operator seat mounted to the excavator, and provides a means for communicating with the main control unit 250 . An excavator control unit (ECU) 255 communicates with the main control unit 250 and is responsive to operator inputs received from the main user interface 101 to cooperatively control the operation of the excavator. A computer or programmable controller 182 is preferably incorporated as a component of the excavator control unit 255 to control and moderate excavator function.
[0036] The movement and direction of an excavator is preferably monitored and, if desired, moderated by a geographic positioning unit (GPU) 254 . The geographic positioning unit 254 preferably includes a mobile transponder mounted to the excavator and one or more reference transponders. Position reference signals produced by the reference transponders are processed by a CPU 270 of the geographic positioning unit 254 into geographic position data, such as latitude, longitude, and elevation data, and displacement data from one or more reference locations, for example.
[0037] An important component of the novel data acquisition and control system concerns a geophysical data acquisition unit (GDAU) 256 , which acquires various types of geological and geophysical data for a particular excavation site. In one embodiment, the geophysical data acquisition unit 256 may be decoupled from the main control unit 250 to provide for initial surveying of a predetermined excavation site. After performing the initial survey, the data acquired by the geophysical data acquisition unit 256 is preferably downloaded into the RAM 266 or EEPROM 268 of the main control unit 250 . Alternatively, the geophysical data acquisition unit 256 is preferably coupled to the excavator and directly to the main control unit 250 to provide real-time acquisition of geological, geophysical, and position data during excavation. In yet another embodiment, initial surveying of an excavation site provides for the acquisition of pertinent geological, geophysical, and position data which is downloaded to the main control unit 250 upon completion of the initial survey. An onboard geophysical data acquisition unit 256 , which preferably includes the components used in the initial survey, provides for real-time data acquisition which may be used in conjunction with the data acquired from the initial survey to optimize excavator production performance. The geophysical data acquisition unit 256 preferably includes a CPU 276 , RAM 278 , and EEPROM 280 .
[0038] Among the various types of data acquired by the geophysical data acquisition unit 256 , data pertaining to the specific geology at the excavation site, in addition to the physical characteristics of such geology, are of particular importance when optimizing the production performance of an excavator, and when estimating the cost and resource allocation of a particular excavation project. A geologic imaging unit (GIU) 258 is preferably coupled to the geophysical data acquisition unit 256 to provide information concerning the particular geology associated with an excavation site. Various geophysical characteristics associated with a particular geology at the excavation site are preferably determined by a geophysical characterization unit (GCU) 260 . An auxiliary user interface (AUI) 262 is preferably coupled to the geophysical data acquisition unit 256 to provide local viewing of acquired data and images, and to provide a means for an operator to communicate with the geophysical data acquisition unit 256 . The auxiliary user interface 262 is particularly useful in connection with an embodiment in which the geophysical data acquisition unit 256 is decoupled from the main control unit 250 to perform an initial survey of an excavation site. It is noted that RS-232 communication lines provide sufficient bandwidth for effecting communication between the electronic units and instruments of the novel data acquisition and control system.
[0039] Geophysical Data Acquisition Unit (GDAU)
[0040] As shown in FIG. 5, the geophysical data acquisition unit 256 preferably includes a geologic imaging unit 258 and a geophysical characterization unit 260 . The geophysical characterization unit 260 preferably includes a number of geophysical instruments which provide a physical characterization of the geology for a particular excavation site. A seismic mapping module 286 includes an electronic device consisting of multiple geophysical pressure sensors. A network of these sensors are arranged in a specific orientation with respect to the excavator, and are situated so as to make direct contact with the ground. The network of sensors measures ground pressure waves produced below the excavator and in the trench walls produced by the excavator. Analysis of ground pressure waves received by the network of sensors provides a basis for determining the physical characteristics of the subsurface at the excavation site. This data is preferably processed by the CPU 276 of the geophysical data acquisition unit 256 or, alternatively, by the CPU 264 of the main control unit 250 .
[0041] A point load tester 288 may be employed to determine the geophysical characteristics of the subsurface at the excavation site. The point load tester 288 preferably employs a plurality conical bits for the loading points which, in turn, are brought into contact with the ground to test the degree to which a particular subsurface can resist a calibrated level of loading. The data acquired by the point load tester 288 provides information corresponding to the geophysical mechanics of the soil under test. This data may also be transmitted to the geophysical data acquisition unit 256 for storage in the RAM 278 or EEPROM 280 .
[0042] The geophysical characterization unit 260 preferably includes a Schmidt hammer 290 , which is a geophysical instrument that measures the rebound hardness characteristics of a sampled subsurface geology. Other geophysical instruments may also be employed to measure the relative energy absorption characteristics of a rock mass, abrasivity, rock volume, rock quality, and other physical characteristics that together provide information regarding the relative difficulty associated with excavating a given geology. The data acquired by the Schmidt hammer 290 is also preferably stored in the RAM 278 or EEPROM 280 of the geophysical data acquisition unit 256 .
[0043] The geologic imaging unit 258 preferably includes a ground penetrating radar system (GPRadar) 282 and an antenna system 284 . The GPRadar system 282 cooperates with the antenna system 284 to transmit source electromagnetic signals into the subsurface of an excavation site. The source electromagnetic signals penetrate the subsurface and are reflected back to the antenna system 284 . The reflected source electromagnetic signals received by the antenna system 284 are amplified and conditioned by the GPRadar system 282 . In one embodiment, analog reflected source electromagnetic signals processed by the GPRadar system 282 are preferably digitized and quantized by a quantizer 281 . In another embodiment, a digitizing GPRadar system 282 performs analog-to-digital conversion of the reflected source electromagnetic signals. The digitized radar data acquired by the geologic imaging unit 258 is preferably stored in RAM 278 or non-volatile EEPROM 280 memory in the geophysical data acquisition unit 256 .
[0044] Referring now to FIG. 6, there is illustrated a visual illustration of typical geologic imaging data acquired from a GPRadar System 282 employing a conventional single-axis antenna system 284 . In FIG. 6, there is plotted GPRadar system 282 data acquired over a test site having five different man-made hazards buried at a depth of approximately 1.3 meters in sandy soil with a water table located at a depth of approximately four to five meters. It is noted that the data illustrated in FIG. 6 is representative of data typically obtainable by use of a PulseEKKO 1000 system manufactured by Sensors and Software, Inc. using conventional single-axis 450 MHz center frequency antennas. Other GPRAdar systems 282 which may be suitable for this application include SIR System-2 and System-10A manufactured by Geophysical Survey Systems, Inc. and model 1000B STEPPED-FM Ground Penetrating Radar manufactured by GeoRadar, Inc.
[0045] Each of the buried hazards illustrated in FIG. 6 has associated with it a characteristic hyperbolic time-position curve. The apex of the characteristic hyperbolic curve provides an indication of both the position and the depth of a buried hazard. It can be seen from the graph of FIG. 6 that each of the buried hazards is located approximately 1.3 meters below the ground surface, with each of the hazards being separated from adjacent hazards by a horizontal distance of approximately five meters. The GPRadar System 282 data illustrated in FIG. 6 represents geological imaging data acquired using a conventional single-axis antenna system and, as such, only provides a two-dimensional representation of the subsurface being surveyed. As will be discussed in greater detail hereinbelow, a novel antenna system 284 comprising multiple antennas arranged in an orthogonal orientation provides for an enhanced three-dimensional view of the subsurface geology associated with a particular excavation site.
[0046] Geographic Positing Unit (GPU)
[0047] Turning now to FIG. 7, there is illustrated in greater detail a geographic positioning unit 254 that provides geographic position information regarding the position, movement, and direction of an excavator over an excavation site. In one embodiment, the geographic positioning unit 254 communicates with one or more external reference signal sources to determine information regarding the position of an excavator relative to one or more known reference locations. The relative movement of an excavator over a specified excavation route is preferably determined by the CPU 270 of the geographic positioning unit 254 , and stored as position data in RAM 272 or EEPROM 274 .
[0048] In another embodiment, geographic position data for a predetermined excavation route is preferably acquired prior to excavating the route. This position data may be uploaded into a navigation controller 292 which cooperates with the main control unit 250 and the excavator control unit 255 to provide autopilot-like control and maneuvering of the excavator over the predetermined excavation route. In yet another embodiment, position data acquired by the geographic positioning unit 254 is preferably communicated to a route mapping database 294 which stores the position data for a given excavation site, such as a grid of city streets or a golf course under which various utility, communication, plumbing, and other conduits are buried. The data stored in the route mapping database 294 may be subsequently used to produce a survey map that accurately specifies the location and depth of various utility conduits buried in a specified excavation area.
[0049] In one embodiment, a global positioning system (GPS) 296 is employed to provide position data for the geographic positioning unit 254 . In accordance with a U.S. Government project to deploy twenty-four communication satellites in three sets of orbits, termed the Global Positioning System (GPS) or NAVSTAR, various signals transmitted from one or more GPS satellites may be used indirectly for purposes of determining positional displacement of an excavator relative to one or more known reference locations. It is generally understood that the U.S. Government GPS satellite system provides for a reserved or protected band and a civilian band. Generally, the protected band provides for high-precision positioning to an accuracy of approximately one to ten feet. The protected band, however, is generally reserved exclusively for military and governmental surveillance purposes, and is modulated in such a manner as to render it virtually useless for civilian applications. The civilian band is modulated so as to significantly decrease its usefulness in high-accuracy applications. In most applications, positional accuracies of approximately one hundred to three hundred feet are typical using the civilian band.
[0050] The civilian GPS band, however, can be used indirectly in relatively high-accuracy applications by using one or more civilian GPS signals in combination with one or more ground-based reference signal sources. By employing various known signal processing techniques, generally referred to as differential global positioning system (DGPS) signal processing techniques, positional accuracies on the order of one foot or less are achievable. As shown in FIG. 7, the global positioning system 296 utilizes a signal produced by at least one GPS satellite 302 in cooperation with signals produced by at least two base transponders 304 , although use of one base transponder 304 may be satisfactory in some applications. Various known methods for exploiting differential global positioning signals using one or more base transponders 304 , together with a GPS satellite signal 302 and a mobile GPS receiver 303 mounted to the excavator, may be employed to accurately resolve excavator movement relative to base transponder 304 reference locations using a GPS satellite signal source.
[0051] In another embodiment, a ground-based positioning system may be employed using a range radar system 298 . The range radar system 298 preferably includes a plurality of base radio frequency (RF) transponders 306 and a mobile transponder 308 mounted to the excavator. The base transponders 306 emit RF signals which are received by the mobile transponder 308 . The mobile transponder 308 preferably includes a computer that calculates the range of the mobile transponder 308 relative to each of the base transponders 306 through various known radar techniques, and then calculates its position relative to all base transponders 306 . The position data acquired by the range radar system 298 is preferably stored in the RAM 272 or EEPROM 274 of the geographic positioning unit 254 .
[0052] An ultra-sonic positioning system 300 , in another embodiment, may be employed together with base transponders 310 and a mobile transponder 3 l 2 mounted to the excavator. The base transponder 310 emits signals having a known clock timebase which are received by the mobile transponder 312 . The mobile transponder 312 preferably includes a computer which calculates the range of the mobile transponder 312 relative to each of the base transponders 310 by referencing the clock speed of the source ultrasonic waves. The computer of the mobile transponder 312 also calculates the position of the excavator relative to all of the base transponders 310 . It is to be understood that various other known ground-based and satellite-based positioning systems may be employed to accurately determine excavator movement along a predetermined excavation route.
[0053] Excavator Control Unit (ECU)
[0054] Referring now to FIG. 8, there is illustrated a system block diagram of an excavator control unit (ECU) 255 which communicates with the main control unit (MCU) 250 to coordinate the operation of an excavator. In accordance with an embodiment of the track trencher excavator 30 illustrated in FIGS. 1 and 2, the left track drive 34 typically comprises a left track pump 38 coupled to a left track motor 42 , and the right track drive 32 typically comprises a right track pump 40 coupled to a right track motor 44 . Left and right track motor sensors 198 and 192 are preferably coupled to the left and right track motors 42 and 44 , respectively. The left and right track pumps 38 and 40 , deriving power from the engine 36 , preferably regulate oil flow to the left and right track motors 42 and 44 which, in turn, provide propulsion for the left and right track drives 34 and 32 . The excavation attachment 46 preferably comprises an attachment motor 48 and an attachment control 98 , with the attachment 46 preferably deriving power from the engine 36 . A sensor 186 is preferably coupled to the attachment motor 46 . Actuation of the left track motor 42 , right track motor 44 , and attachment motor 48 is monitored by sensors 198 , 192 , and 186 respectively. The output signals produced by the sensors 198 , 192 , and 186 are communicated to the computer 182 .
[0055] In response to steering and propel control signals respectively produced by the steering control 92 and propel control 90 , the computer 182 communicates control signals, typically in the form of control current, to the left and right track pumps 38 and 40 which, in turn, regulate the speed at which the left and right track motors 42 and 44 operate. The left and right track motor sensors 198 and 192 communicate track motor sense signals to the computer 182 indicative of the actual speed of the left and right track motors 42 and 44 . Similarly, an engine sensor 208 , coupled to the engine 36 , provides an engine sense signal to the computer 182 , thus completing a closed loop control system for the tractor drive portion 45 of a track trencher 30 . Those skilled in the art will recognize that various known computer configurations will provide a suitable platform for effectuating propulsion and steering changes of a track trencher 30 in response to the propel and steering signals produced by the propel and steering controls 90 and 92 .
[0056] The excavation attachment 46 portion of a track trencher 30 includes an attachment motor 48 , attachment control 98 , and at least one attachment sensor 186 . The attachment motor 48 preferably responds to instructions communicated to the attachment control 98 from the computer 182 . The actual output of the attachment motor 48 is monitored by the attachment sensor 186 , which produces an attachment sense signal received by the computer 182 .
[0057] In one embodiment, the left and right track motor sensors 198 and 192 are of a type generally referred to in the art as magnetic pulse pickups, or PPUs. The PPUs 198 and 192 transduce track motor rotation into a continuous series of pulse signals, wherein the pulse train preferably represents the frequency of track motor rotation as measured in revolutions-per-minute. When a transport mode of travel is selected, the propel control 90 preferably produces a transport propel control signal which is representative of a target velocity for the left and right track motors 42 and 44 , typically measured in revolutions-per-minute. Conversion of the transport propel signal into a target track motor velocity may be accomplished by the propel control 90 itself or, preferably, by the computer 182 . The computer 182 typically compares the left and right track motor sense signals respectively produced by the left and right PPU sensors 198 and 192 to the target track motor propulsion level represented by the transport propel signal. The computer 182 communicates the appropriate pump control signals to the left and right track pumps 38 and 40 in response to the outcome of the comparison to compensate for any deviation between the actual and target track motor propulsion levels.
[0058] A display 73 is coupled to the computer 182 or, alternatively, to the main control unit 250 , and preferably communicates messages indicative of operating status, diagnostic, calibration, fault, safety, and other related information to an operator. The display 73 provides quick, accurate, and easy-to-understand information to an operator by virtue of the interpretive power of the computer 182 which acquires and processes data from a plurality of track trencher sensors, and various geological and geophysical instruments. Geologic imaging data and related geophysical information, for example, is visually displayed on the display 73 . Further, information regarding the position of the excavator as it traverses along a predetermined excavation route, as well as signal quality information received from the geographic positioning unit 254 , is displayed on the display 73 . A keyboard 75 is also provided on the main user interface 101 to permit an operator to communicate with the excavator control unit 255 and the main control unit 250 .
[0059] Main Control Unit (MCU)
[0060] Turning now to FIG. 9, there is illustrated a block diagram of various databases and software that are utilized by the main control unit (MCU) 250 when accessing and processing geological, geophysical, position, and operational data associated with surveying and excavating a selected excavation site. The data acquired by the geophysic data acquisition unit 256 , for example, is preferably stored in a database 326 , which includes a GPRadar database 328 , a geologic filter database 330 , and a geophysics database 332 . The GPRadar system 282 data, as previously discussed, is preferably digitized and stored in the GPRadar database 328 in a suitable digital format appropriate for correlation to data stored in other system databases. A geologic filter database 330 , as will be discussed in greater detail hereinbelow, includes filtering data produced by correlating GPRadar data to corresponding excavator production data stored in the excavation performance database 324 . Correlation and optimization software 320 performs the correlation of GPRadar data to actual excavator production data to develop an array of adjustable geologic digital filters that can be effectively overlaid with real-time acquired geologic image data to exclude or “filter out” verified geology data, thus leaving unverified images representative of one or more buried hazards. By way of further illustration, a particular type of soil produces a characteristic return radar image which can be correlated with excavator production data acquired by the excavator control unit 255 . Excavating through granite, for example, produces a characteristic return radar image that can be correlated to various excavator operation parameters, such as excavation attachment motor 48 speed, engine 36 loading, and left or right track motor 42 and 44 velocity changes.
[0061] An “excavation difficulty” parameter or set of parameters are preferably computed based on the excavator operating parameters. The “excavation difficulty” parameters are then associated with the characteristic reflected radar image data corresponding to a particular geology, such as granite, for example. An array of “excavation difficulty” filter parameters and associated reflected radar image data values are preferably developed for a wide range of soil and rock, and stored in the geologic filter database 330 .
[0062] An excavation statistics database 316 preferably receives data files from the correlation and optimization software 320 and compiles statistical data to reflect actual excavator production performance relative to specific geology, maintenance, and equipment variables. In one embodiment, GPRadar data and geophysical data is acquired by the geophysic data acquisition unit 256 during an initial survey of a predetermined excavation route. This data is preferably uploaded to the excavation statistics database 316 prior to excavating the predetermined route. The data stored in the excavation statistics database 316 can be viewed as a production estimate in the sample geology based on past excavator production performance.
[0063] The main control unit 250 also executes ECU control software 318 which receives data files from the correlation and optimization software 320 and input commands received from the main user interface 101 . The ECU control software 318 compiles a current operation standard for operating the excavator over the course of the predetermined excavation route. If input data received from the main user interface 101 causes a modification in the operation standard, the ECU control software 318 computes modified excavator operational instructions which are transmitted to the main control unit 250 and the excavator control unit 255 which, in turn, modifies the operation of the excavator in response to the modified operation standard.
[0064] A maintenance log memory 314 preferably includes non-volatile memory for storing various types of excavator maintenance information. An elapsed time indicator is preferably included in the maintenance log memory 314 which indicates the total elapsed operating time of the excavator. At predefined operating time values, which are preferably stored in the maintenance log memory 314 , the excavator operator is prompted by the main user interface 101 that scheduled service is required. Verification of scheduled service, the type of service, the date of service, and other related information is preferably input through the main user interface 101 for permanent storage in the maintenance log memory 314 . In one embodiment, the maintenance log memory 314 preferably includes a table of factory designated operational values and ranges of operational values associated with nominal excavator operation. Associated with each of the operational values and ranges of values is a status counter which is incremented upon each occurrence of excavator operation outside of the prescribed values or range of values. The status counter information is useful in assessing the degree to which an excavator has been operated outside factory specified operational ranges, which is particularly useful when determining the appropriateness of warranty repair work.
[0065] Geologic Surveying and Imaging
[0066] In general operation, as shown in FIG. 10, a predetermined excavation route is preferably initially surveyed using the geographic positioning unit 254 and the geophysic data acquisition unit 256 . In one embodiment, the geographic positioning unit 254 and geophysic data acquisition unit 256 are positioned in a transport cart 340 which is pulled along the predetermined excavation route by a vehicle 342 . In the illustrative example shown in FIG. 10, the excavation route is a county road under which a utility conduit is to be installed. As the transport cart 340 is pulled along the roadway 344 , data received from the geologic imaging unit 258 is acquired for the purpose of determining the soil properties of the subsurface below the roadway 344 . Concurrently, geographic position data is acquired by the geographic positioning unit 254 as the vehicle 342 and transport cart 340 traverse the roadway 344 . As such, specific geologic data obtained from the geologic imaging unit 258 may be correlated to specific geographic locations along the roadway 344 .
[0067] The geologic imaging unit 258 preferably includes a GPRadar system 282 which is typically calibrated to penetrate to a pre-established depth associated with a desired depth of excavation. Depending on the pre-determined excavation depth, various types of soil and rock may be encountered along the predetermined excavation route. As shown in FIG. 10, a layer of road fill 346 , which lies immediately below the roadway 344 , has associated with it a characteristic geologic profile GP 1 and a corresponding geologic filter profile GF 1 which, as previously discussed, represents a correlation between excavation production performance data to reflected radar image data for a particular soil type. As the transport cart 340 traverses the roadway 344 , various types of soil and subsurface structures are detected, such as a sand layer 354 , gravel 352 , bedrock 350 , and native soil 348 , each of which has a corresponding characteristic geologic profile and geologic filter profile.
[0068] Upon completion of the initial survey, the data acquired and stored in the geophysic data acquisition unit 256 and geographic positioning unit 254 is preferably downloaded to a separate personal computer (PC) 252 . The PC 252 preferably includes excavation statistics software and an associated database 316 to correlate the acquired survey data with historical excavator production performance data to produce an estimation as to expected excavator performance over the surveyed route. The performance estimates may further be used as a basis for computing the time and cost involved in excavating a particular area based on actual geological data and historical production performance data.
[0069] After completion of the initial survey, the geophysic data acquisition unit 256 is preferably coupled to the main control unit 250 on the excavator prior to initiating excavation along the surveyed route. During excavation, as previously discussed, the various databases containing geological, geophysical, position, and excavator operating performance data are processed by the main control unit 250 . The main control unit 250 , in cooperation with the excavator control unit 255 , adjusts the operation of the excavator as it traverses and excavates along the surveyed route to optimize excavation.
[0070] Referring now to FIG. 11, there is illustrated an example of a survey profile obtained by transporting the geophysic data acquisition unit 256 and geographic positioning unit 254 along a predetermined excavation route. It is noted that in this illustrative example, the length of the excavation route is defined as the distance between Location L 0 and Location L 5 . A corresponding estimated excavation production profile for the predetermined excavation route is shown in FIG. 12.
[0071] Referring to FIG. 11 in greater detail, distinct changes in subsurface geological characteristics can be observed at locations L 1 , L 2 , L 3 , and L 4 , which are associated with corresponding changes in the “excavation difficulty” parameter plotted along the Y-axis of the survey profile chart. Between locations L 0 and L 1 , for example, the geologic profile GP 1 362 of the subsurface has associated with it a corresponding excavation difficulty parameter of D 1 . The geologic imaging data at L 1 indicates a transition in the subsurface geology to soil having a geologic profile of GP 2 364 and a corresponding excavation difficulty parameter of D 2 , thus indicating a transition to relatively softer soil.
[0072] The estimated excavation production profile data shown in FIG. 12 indicates a corresponding transition from an initial production profile PP 1 372 to another production profile PP 2 374 at location L 1 . It is noted that the rate of excavation is plotted along the Y-axis of the excavation production profile chart. Based on the survey profile data for the subsurface geological characteristics between locations L 0 and L 2 , it can be seen that an initial excavation rate R 1 is estimated for the portion of the predetermined excavation route between locations L 0 and L 1 , and an increased excavation rate of R 2 between excavation route locations L 1 and L 2 due to the lower excavation difficulty parameter D 2 associated with geologic profile GP 2 364 . It can be seen that a similar relationship exists between a particular excavation difficulty parameter and its corresponding estimated excavation rate parameter.
[0073] In general, excavation difficulty parameters of increasing magnitude are associated with corresponding excavation rate parameters of decreasing magnitude. This generalized inverse relationship reflects the practical result that excavating relatively hard soil, such as granite, results in a relatively low excavation rate, while excavating relatively soft soil, such as sand, results in relatively high excavation rates. It is noted that associated with each particular geologic profile (GP X ) and production profile (PP X ), there exists a corresponding excavation time, such as excavation time T 1 associated with geologic profile GP 1 362 and production profile PP 1 372 . As such, a total estimated excavation time for a particular predetermined excavation route can be obtained by summing each of the individual excavation time parameters T 1 through T N .
[0074] The survey profile data of FIG. 11 associated with geologic profile GP 4 368 between excavation route locations L 3 and L 4 indicates a discontinuity at this location. The excavation production profile data of FIG. 12 corresponding to this portion of the predetermined excavation route indicates a corresponding discontinuity in the excavation rate estimation which is shown diverging toward zero. The data for this portion of the predetermined excavation route indicates the existence of extremely tough soil or, more likely, a man-made hazard, such as a concrete or steel pipeline, for example. Further investigation and surveying of the specific area may be warranted, which may require removal of the hazard or modification to the predetermined excavation route.
[0075] A more realistic geologic profile for a particular length of the predetermined excavation route is illustrated as geologic profile GP 5 370 shown between excavation route locations L 4 and L 5 . The excavation difficulty parameter for this geologic profile results in an averaged parameter of D 5 . Accordingly, an averaged excavation rate of R 5 may be appropriate when excavating this portion of the predetermined route. Alternatively, the excavation rate associated with the production profile PP 5 380 may be moderated by the excavator control unit 255 to optimize the excavation rate based on such fluctuations in excavation difficulty. It is understood that the ability of an excavator to respond to such fluctuations in excavation rate is generally limited by various mechanical and operational limitations.
[0076] Turning now to FIG. 13, there is illustrated a heterogeneous composition of differing soil types over a predetermined excavation route having a predefined distance of L S . The soil in region 1 , for example, has a geologic profile of GP 1 and a corresponding geologic filter profile of GF 1 . Each of the other soil types illustrated in FIG. 13 has a corresponding geologic profile and geologic filter profile value. It is assumed that the geologic filter database 330 contains geologic filter data for each of the regions 1 , 2 , 3 and 4 illustrated in FIG. 13. A significant advantage of the novel hazard detection process performed by the geophysic data acquisition unit 256 concerns the ability to quickly detect the existence of an unknown buried structure 401 . The correlation and optimization software 320 executed by the main control unit 250 preferably filters out known geology using a corresponding known geologic filter profile to exclude the known or verified geology data from data associated with a survey scan image. Filtering out or excluding the known or verified geology data results in imaging only unverified buried structures 401 . By excluding known geological data from geologic imaging survey scan data, unknown or suspect buried structures are clearly recognizable.
[0077] Referring now to FIG. 14, there is illustrated a conventional antenna configuration for use with a ground penetrating radar system. Generally, a single-axis antenna, such as the one illustrated as antenna-A 382 oriented along the Z-axis, is employed to perform multiple survey passes 384 when attempting to locate a potential buried hazard 386 . Generally, a ground penetrating radar system has a time measurement capability which allows measuring of the time for a signal to travel from the transmitter, bounce off a target, and return to the receiver. This time function can be calibrated to the velocity of a specific subsurface condition in order to measure distance to a subsurface object or horizon. Calculations can be used to convert this time value to a distance measurement that represents the depth of the target based upon field determined values for characteristic soil properties, such a dielectric and wave velocity through a particular soil type. A simplified technique that can be used when calibrating the depth measurement capabilities of a particular ground penetrating radar system involves coring a sample target, measuring its depth, and relating it to the number of nanoseconds it takes a wave to propagate.
[0078] After the time function capability of the ground penetrating radar system provides an operator with depth information, the radar system is moved laterally in a horizontal (X) direction, thus allowing for the construction of a two-dimensional profile of a subsurface. By performing multiple survey passes in a series of parallel lines 384 over a particular site, a buried hazard 386 may be located. It can be appreciated, however, that the two-dimensional imaging capability of a conventional antenna configuration 382 can result in missing a buried hazard 386 , particularly when the hazard 386 is parallel to the direction of a survey pass 384 .
[0079] A significant advantage of a novel geologic imaging antenna configuration 284 provides for three-dimensional imaging of a subsurface as shown in FIG. 15. A pair of antennas, antenna-A 388 and antenna-B 390 , are preferably employed in an orthogonal configuration to provide for three-dimensional imaging of a buried hazard 386 . It is noted that the characteristic hyperbolic time-position data distribution, as shown in two-dimensional form in FIG. 6 by use of a conventional single-axis antenna, may instead be plotted as a three-dimensional hyperbolic shape that provides width, length, and breadth dimensions of a detected buried hazard 386 . It is further noted that a buried hazard 386 , such as a drainage pipeline, which runs parallel to the survey path 392 will immediately be detected by the three-dimensional imaging GPRadar system 282 . Respective pairs of orthogonally oriented transmitting and receiving antennas are preferably employed in the antenna system 284 of the geological imaging unit 258 .
[0080] Excavation Site Mapping
[0081] Turning now to FIG. 16, there is illustrated an excavator 410 performing an excavation operation along a city street 420 of a city street grid 422 . An important advantage of the novel geographic positioning unit 254 of the excavator 410 concerns the ability to accurately navigate along a predetermined excavation route, such as a city street 420 , and to accurately map the excavation route in a route mapping database 294 coupled to the geographic positioning unit 254 . It may be desirable to initially survey a city street grid 422 for purposes of accurately establishing an excavation route for each of the applicable city streets 420 comprising the city street grid 422 , for example. This data is preferably loaded into the navigation controller 292 of the geographic positioning unit 254 .
[0082] As the excavator 410 progresses along the excavation route defined for each of the city streets 420 , actual position data is acquired by the geographic positioning unit 254 and stored in the route mapping database 294 . Any deviation from the predetermined excavation route stored in the navigation controller 292 is accurately recorded in the route mapping database 294 . Upon completion of an excavation effort, the data stored in the route mapping database 294 may be downloaded to a PC 252 to construct an “as built” excavation map of the city street grid 422 .
[0083] Accordingly, an accurate survey map of utility or other conduits installed along the excavation route mav be constructed from the route mapping data and subsequently referenced by workers desiring to gain access to, or avoid, the buried conduits. It is to be understood that excavating one or more city streets for the purpose of installing utility conduits as shown in FIG. 16 is provided for illustrative purposes, and does not represent a limitation on the application of the geographic positioning and route mapping capability of the novel excavator data acquisition and control system.
[0084] Still referring to FIG. 16, accurate navigation and mapping of a prescribed excavation route may be accomplished by a global positioning system 296 , range radar system 298 or ultrasonic positioning system 300 , as discussed previously with respect to FIG. 7. An excavator data acquisition and control system utilizing a GPS 296 configuration preferably includes first and second base transponders 404 and 408 together with one or more GPS signals received from a corresponding number of GPS satellites 302 . A mobile transponder 402 , preferably mounted to the excavator 410 , is provided for receiving the GPS satellite signal 412 and base transponder signals 414 and 418 respectively transmitted from the base transponders 404 and 408 . As previously discussed, a modified form of differential GPS positioning techniques may be employed to enhance positioning accuracy to one foot or less.
[0085] In another embodiment, a ground-base range radar system 298 includes three base transponders 404 , 408 , and 406 and a mobile transponder 402 mounted to the excavator 410 . It is noted that a third ground-based transponder 406 may be provided as a backup transponder for a system employing a GPS satellite signal 412 in cases where a GPS satellite signal 412 transmission is temporarily terminated. Position data is preferably processed and stored by the geographic positioning unit 254 using the three reference signals 414 , 416 , and 418 received from the three ground-based radar transponders 404 , 406 , and 408 . An embodiment employing an ultrasonic positioning system 300 would similarly employ three base transponders, 404 , 406 , and 408 together with a mobile transponder 402 mounted to the excavator 410 .
[0086] Eacavator Data Acquisition and Control Process
[0087] Turning now to FIGS. 17 - 20 , there is illustrated in flowchart form generalized process steps associated with the novel excavator data acquisition and control system and process. Initially, as shown in FIG. 17, a number of ground-based transponders are positioned at appropriate locations along a predetermined excavation route at step 500 . The geophysic data acquisition unit 256 and geographic positioning unit 254 are then situated at an initial location L 0 of the excavation route at step 502 . The geologic imaging unit 258 , geophysical characterization unit 260 , and geographic positioning unit 254 are then initialized or calibrated at step 504 . After initialization, the geophysic data acquisition unit 256 and geographic positioning unit 254 are transported along the excavation route, during which GPRadar, position, and geophysical data is acquired at steps 506 , 508 , and 510 . The data acquired by the GPRadar system 282 is preferably digitized and quantized at step 512 . Data acquisition continues at step 516 until the end of the excavation route is reached, as at step 518 . The acquired data is then preferably downloaded to a PC 252 or directly to the main control unit 250 .
[0088] At step 530 , shown in FIG. 18, excavation statistical software is preferably executed on the data acquired during the excavation route survey. At step 532 , historical excavator production data is transferred from the excavation statistics database 316 to the PC 252 . The data acquired during the survey is also loaded into the PC at step 534 . The excavation statistical software then performs a correlation between the acquired GPRadar data and the historical excavator production data step 536 .
[0089] In one embodiment, correlation between GPRadar data and historical production data is accomplished by use of various known matrix manipulation techniques. A historical production data matrix is preferably produced at step 538 by correlating geologic image data (ID X ) with corresponding excavator production data (PD X ). A correlation value (CV XX ) is produced corresponding to each pair of geologic image data and production data parameters. The correlation value CV 22 , for example, is a correlation value associated with a statistical correlation between geologic image data parameter ID 2 and excavator production data parameter PD 2 . Associated with each geologic image data parameter is an associated time parameter and location parameter, such as T 1 and L 1 associated with geologic image data parameter ID 1 . It can be seen that correlation values associated with a plurality of geologic image data and production data parameter pairs can be produced for time and position increments along a predetermined excavation route.
[0090] At step 540 , actual geologic image data is acquired over the excavation route and preferably processed as a matrix of discrete geologic image data for corresponding discrete time and location distance increments. At step 542 , the matrices produced at steps 538 and 540 are manipulated to produce a correlation matrix in which an estimated or projected production data parameter (PD XX ) is associated with a pair of corresponding actual geologic image data (ID X ) and correlation value (CV X ) parameter pairs. For example, an estimated production data parameter PD 3 is associated with actual geologic image data parameter ID 3 and correlation value parameter CV 3 . It is noted that each of the estimated production data parameters is associated with a corresponding time and distance location increment.
[0091] The estimated production performance parameters for a particular excavation route are computed at step 550 as shown in FIG. 19. The total estimated time (ET T ) to excavate the entire excavation route can be estimated by summing the discrete time increments T 1 through T N . The operational costs associated with excavating the predetermined excavation route can be determined by summing the operational costs associated with each of the discrete portions along the route. The estimated labor costs (LC T ) can be estimated by multiplying the total estimated excavation time (ET T ) by the total man hour cost per hour. An estimation of the grand total of costs (GT E ) can be determined by summing all of the production costs and labor costs associated with excavating the entire route.
[0092] At step 552 , the estimated excavator operation parameters are computed. For the portion of the excavation route defined between reference location L 0 and L 1 , for example, the estimated production data may indicate an optimal left track velocity (V L ) of 125 feet per minute (FPM) and a right track velocity (V R ) of 125 FPM. Further, the estimated production data may suggest an optimal excavation attachment speed of approximately 110 RPM and a target engine speed of 2.250 RPM. It is noted that the left and right track velocities V L and V R of 125 FPM, respectively, represents straight tracking by the excavator along the excavation route.
[0093] It can be seen that along the excavation route defined between location L 1 and L 2 , it is indicated that the excavator is steering in a right direction since the left track velocity V 1 of 230 FPM is greater than the right track velocity V R of 150 FPM. Also, it is indicated that the excavating attachment speed is increasing to 130 RPM, and that the target engine speed is increasing to 2.400 RPM, thus indicating the presence of relatively softer soil within the region defined between locations L 1 and L 2 . Along the excavation route defined between locations L 2 and L 3 , it is indicated that the excavator is again tracking in a straight direction and at a relatively slow velocity of 60 FPM, thus indicating the presence of relatively hard subsurface soil. A corresponding slower excavating attachment speed of 100 RPM and lower target engine speed of 2,100 RPM are indicated due to the slower excavator velocity.
[0094] At step 560 , as shown in FIG. 20, the estimated excavation operating parameters produced at step 552 are loaded into the main control unit 250 . Excavation is initiated beginning at reference location L 0 at step 562 . At step 564 , the main control unit 250 monitors the excavator operational parameters, and out-of-range conditions are recorded in the maintenance log memory 314 . Actual production performance parameters are acquired by the excavator control unit 255 , at step 568 , and transferred to the main control unit 250 . Any inputs received from the main user interface 101 are also transferred to the main control unit at step 570 . If the actual production performance parameters received from the excavator control unit 255 differ by a predetermined amount from the estimated excavation operation parameters, as tested at step 572 , the main control unit 250 optimizes the estimated parameters at step 574 , and transmits the optimized parameters to the excavator control unit 255 to effect the necessary changes to excavator operation at step 576 . Excavation continues at step 578 until the end location of the predetermined excavation route is reached at step 580 , after which the excavation operation is terminated as at step 582 .
[0095] It will, of course, be understood that various modifications and additions can be made to the preferred embodiments discussed hereinabove without departing from the scope or spirit of the present invention. Accordingly, the scope of the present invention should not be limited by the particular embodiments discussed above, but should be defined only by the claims set forth below and equivalents of the disclosed embodiments. | A portable structure supports a subsurface imaging system and is moveable over a given imaging site. At least a first antenna of a plurality of antennae is oriented in a manner differing from an orientation of a second antenna of the plurality of antennae, such as the first antenna being orientated substantially orthogonal to the second antenna. The antennae may operate in a bi-static mode. Transmitter and receiver circuitry, coupled to the antennae, respectively generates electromagnetic probe signals and receives electromagnetic return signals resulting from the probe signals. A processor processes the received electromagnetic return signals. A display may be provided as part of the subsurface imaging system and/or as part of a processing system separate from the subsurface imaging system which processes the received electromagnetic return signals. The processor can generate two-dimensional and/or three-dimensional detection data using the received electromagnetic return signals. | 4 |
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0001] Not Applicable
CROSS REFERENCE TO RELATED APPLICATIONS
[0002] Not Applicable
REFERENCE TO MICROFICHE APPENDIX
[0003] Not Applicable
BACKGROUND OF THE INVENTION
[0004] 1. This invention is directed to a system comprising a method and apparatus for separating oil and water. In particular, the system is directed to the separation of machining cutting coolant oils, die release agents, oily wash waters, and other emulsified oils from water.
[0005] 2. Metaphorically speaking, oil and water do not mix. But in practice, their separation is a major problem.
[0006] In addition to intentionally created oil/water emulsions such as cutting coolants, industry uses oil for lubrication and water for cooling, etc in a number of processes, and when the two fluids become mixed, they are both effectively contaminated.
[0007] It is thought that a reasonable estimate of such contaminated fluid would be 10 billion litres per year for North America.
[0008] Probably more than two thirds of this volume is trucked away to be treated off site at centralized treatment plants, the rest being treated on the site where it is generated.
[0009] When “coolant” is referred to, in terms of machining cutting coolant, this usually arrives at the machinist's shop in drums of oil concentrate, to be mixed with water to make a ‘working solution’. This may typically be 1% coolant oil concentrate, which forms sub micron oil droplets when mixed with water at 99% by volume.
[0010] The problem of dealing with spent cutting coolants and other oil contaminated waters is presently solved in many instances by shipping comparatively large quantities of contaminated water by truck to a distant processing plant. There is a considerable cost for the haulage as well as the subsequent treatment of the oily waters.
[0011] There is presently developing a global realization of the widespread nature of water contamination.
[0012] Consequent government regulations concerning the handling and disposal of oil-contaminated water also presents problems, both practical and managerial.
[0013] Existing known separation processes include: use of absorbent activated clay, to entrain the oily content; chemical emulsion break plants, for chemically breaking down oil/water emulsions; evaporation technologies relying on differences in boiling point to effect selective evaporation; use of adsorbent and absorbent materials, such as adsorbent carbons (including charcoals); as well as systems that use cross flow membrane technologies.
[0014] In the case of the absorbent clay, the systems are bulky, expensive, messy, and difficult to maintain to specification. These systems require the services of an attendant, and are considered impractical for waste water volumes below 4-million litres per year.
[0015] Chemical de-emulsification plants are very costly, requiring a large floor area, and the services of an operator. In addition to the supply of necessary chemicals, the process also requires considerable energy by way of heat if breaking a chemical emulsion such as machining coolant. Minimum volumes of about 3-4 million litres per annum are desirable, in order to achieve plant efficiency.
[0016] Evaporation technologies require the provision of evaporator tanks, and include heating the total volume of liquid to the vapor point of water, and require a large working area.
[0017] The surfactant present in cutting coolants, when heated in an evaporator, gives off a soapy smell. Also there is no water recovery unless the plant includes a condenser, at considerable capital cost.
[0018] The evaporator tank requires periodic cleaning, with consequent area contamination with oil and coagulants, in and about the work area.
[0019] Chemical polymeric treatments are practicable for certain classes of oily waters. However, in the case of cutting coolants, due to the high degree of chemical emulsification of the oil, the mixed fluid is not practically responsive to the chemistry of cationic polymer water treatment.
[0020] Cross flow membrane filters are effective, in that the two separated fluids are ultimately recovered.
[0021] However, the filter membranes suffer from fouling problems, in which the filtering efficiency is greatly diminished, while cleaning of the membrane is both time consuming and difficult,
[0022] The fouling aspect of filter membrane surfaces used for treating waste waters is possibly the single most reputation-damaging aspect of the technology.
[0023] In larger systems such modules frequently contain a nest of filter elements within a metal cylinder of significant fluid capacity, as much as 200 liters, thus making impractical the use of an in-situ back-wash chemical cleaning regime, in view of the large volume of cleaning chemicals required to fill such a vessel.
SUMMARY OF THE INVENTION
[0024] The present invention provides a practical, compact local system for separating emulsified oil from water, to the extent of enabling treated water to be drained to sewer on an on-going basis. The treated water usually meets regulatory guidelines and thus can be safely put down the drain in the case of water removed from most oily water emulsions.
[0025] The subject system is effective for either highly emulsified oil/water mixes or simpler mechanical emulsions.
[0026] The filter of the present invention uses a ceramic cross-flow membrane filter of membrane pore sizes in the range of 0.005 micron to 1.2 micron. Other pore sizes may be selected for other liquids.
[0027] Operating pressures may be in the range 25 to 150 psi (gauge).
[0028] The subject ceramic filter consists of a sintered ceramic tube composed of aluminum oxide that acts as the support matrix for the ceramic membrane coatings that do the actual “work” of separation. This aluminum oxide matrix is of relatively coarse structure when compared to the ceramic membrane coating that is fused to it internally.
[0029] Running the length of the ceramic element (tube) in arrays of rings concentric with its center, are lumens (open channels) through which the oily waste water flows at high velocity.
[0030] It is upon the walls of these lumens that the actual ceramic (filtering) membrane is bonded by a sintering process. These sintered membranes typically are composed of aluminum oxide, titanium oxide, or zirconium oxide.
[0031] The filter tube is mounted coaxially within a metal cylinder (filter housing), having a predetermined radial clearance from the metal cylinder to form an annular permeate collector space of limited volume about the filter tube.
[0032] The ceramic filter element (held by way of O-rings at either end) within its housing together constitute the filter “module”, which is inserted into the piping of the filter process system.
[0033] The thus formed filter module has end-fittings (unions, flanges, etc) to permit ready removal and replacement from the process circuit.
[0034] Oil contaminated water, which may include other families of contaminants such as metal particles, soap scum etc is referred to hereinafter as waste water.
[0035] For normal filtering operation the waste water is pumped axially through the filter tube at a predetermined minimum velocity of about six meters per second, and at elevated pressure, as a cross-flow in relation to the membrane surface, which enables radial permeation of water outwardly, at right angles to the cross flow, as a flow into and through the wall of the filter element.
[0036] The high cross-flow velocity serves to diminish the tendency of contaminants present in the waste water from adhering to or passing into the wall of the filter tube.
[0037] The thus separated water permeate fills the annular permeate collector space of the filter module, and is led off to drain, or for recycle use.
[0038] When shutting down the system, upon the termination of pumping of the waste water in the processing loop or processing ring an instantaneous back pressure is immediately applied to the permeate water, which pulses it back, radially inwardly through the filter wall, as a back-wash, in a direction reverse to its normal (outward) flow, so as to substantially prevent surface contamination of the filter from the core of slowing or stationary waste water of the processing loop.
[0039] In any “Power off” situation the pump ceases operation and terminates the high velocity cross-flow motion of the waste water across the surface of the ceramic membrane, which cross-flow normally keeps the membrane from fouling.
[0040] The immediate application of an instantaneous back pulse of permeate water into the permeate space of the module protects the membrane surfaces, located internally within the filter, against fouling.
[0041] This back pulse is achieved by the opening operation of a valve that connects the permeate space with a reservoir of clean or permeate water, stored under air pressure.
[0042] During normal system operation, this biassed-open solenoid valve is held in the closed condition by energizing it along with the rest of the operating equipment.
[0043] When de-energised at power-off, the valve snaps open to connect the reservoir of permeate water to the permeate space, into which the water is driven by pressurized air.
[0044] In some instances the reverse pulse of permeate water may even dislodge some infiltrated deliterious substances inwardly, from off the filter body.
[0045] For cleaning the filter of infiltrated corruption, which may include oil, soap scum and other particulate matter carried in the waste water, cleaning solutions may be applied in-situ, without removing the filter module from the circuit.
[0046] These cleaning solutions may include chemicals selected from: sulfuric acid, citric acid, nitric acid, alkaline metal cleaning detergents, hydrogen peroxide, and sodium hydroxide.
[0047] In a first cleaning procedure, with the system re-circulation pumps still running, a predetermined quantity of a cleaning chemical solution may be supplied under pressure to the permeate collector space, to form an interface with the permeate contents, and to displace substantially only the collector permeate contents to the waste tank, by way of coordinated operation of a permeate space dump valve.
[0048] The predetermined quantity of cleaning chemical is selected to just fill the collector space.
[0049] The temperature of the module may then be raised quite rapidly by the simple expedient of continuously recirculating the waste water in a limited closed circuit that includes passage through the filter tube. This action then raises the temperature of the chemical cleaning solution, thereby facilitating its operation in cleaning the pores of the filter.
[0050] The chemical cleaning solution may comprise mutually compatible chemicals that do not adversely affect the respective individual chemical activity of the solution's other chemical constituents.
[0051] Otherwise, non-compatible cleaning chemicals may be admitted individually to the filter module, and used in isolation.
[0052] The warmed cleaning fluid may be pulsed, to enhance its cleaning action and to promote its penetration through the wall of the filter element to eventually reach the innermost membrane surfaces. Such pulsing may be provided by bursts of compressed air driving the cleaning chemical solutions reversely, radially inwardly into the filter.
[0053] Tap water is used after a cleaning cycle is completed, to flush off cleaning chemicals from the module permeate space to the waste storage tank.
[0054] The permeate collector space and associated connected passages may then be, and preferably are, flushed clean with rinse water, which also is discarded to the waste storage tank.
[0055] The radial clearances provided between the ceramic filter element and the cylindrical module housing within which it is enclosed are kept to a minimum, such that the volume of the annular permeate collector space is minimized. This in turn minimizes the repective volumes of cleaning solution and rinse water required for a cleaning cycle, thus making it economically feasible to program frequent and regular cleaning cycles, so as to maintain a consistently high flux rate (the rate of filtering through the module).
[0056] Being carried out in-situ, the cleaning cycle or cycles, which may involve more than one cleaning solution, can be programmed into the system controller.
[0057] In order to maintain the integrity of the filter module against the applied pressure pulses associated with back-washing and with chemical cleaning cycles, a duplex seal arrangement is provided consisting of two O-ring seals at each end of the filter tube which seal the tube to the filter housing.
[0058] A contemplated second (and subsequent) cleaning procedure may consist of:
[0059] Terminating the pumping of waste water within the re-circulation loop;
[0060] Isolating the filter module from the waste water circuit;
[0061] Air-evacuating the processor re-circulation loop by draining waste water from the bottom of the loop, using an air blow-down from the top of the loop;
[0062] Filling the re-circulation loop with tap water, followed by air evacuation, as above, to flush out residual waste water and rinse water;
[0063] Evacuating the filter module permeate space by using tap water to dispell and flush out the previous cleaning chemical solution from the bottom of the loop;
[0064] Continuing a short duration to rinse the permeate space.
[0065] A succeeding cleaning cycle may then follow, the succeeding cleaning solution being similarly admitted into the permeate collector space, again displacing the rinse water to the waste tank. The processor re-circulation loop, being full of tap water, is isolated and run long enough to heat up its contents, such heat being transferred to the new chemical solution in the permeate space of the module.
[0066] Once heated, the cleaning solution is back-pulsed by applied air pressure, to continue the cleaning of the filter, followed by draining of the solution to the waste tank, with water rinsing of the filter module permeate space.
[0067] Before restarting the filtration process, after normal stoppage or after a cleaning cycle, the permeate space may first be filled with clean water, and the permeate collector space pressurized to cause backflow through the filter. This creates a thin film of water, or a reverse flow tendency, in protective relation over the radially inner surface of the filter element prior to resuming recirculation of waste water through the filter.
[0068] Once the processor main pumps re-start and re-circulation loop velocity is re-established, this back-pressure safety is no longer needed, and is terminated, as the waste water now has the requisite cross-flow velocity necessary to substantially obviate surface fouling.
[0069] The filter is operated in a fashion to maintain the requisite operating and flow conditions that promote self-cleaning, so as to minimize surface fouling of the filter, primarily by control of system pressure and the flow velocity through the filter module.
[0070] With the filter in operation it has been found that the increasing percentage of oil in the recirculating waste water or retentate should not exceed a predetermined percentage concentration, as operation with a recirculated retentate of higher oil content than about 40 percent can promote fouling of the filter radially inner, primary flow surface, along which the retentate flows.
[0071] Flux rates also drop off dramatically under a high oil ratio in the retentate.
[0072] It should be appreciated that concentration from a typical, initial 2% to a final 40% oil content is equivalent to the separation and reclamation (or disposal to drain) of 95% of the original water content.
[0073] When the system is operating in its normal mode, an incoming contaminated oil/water mixture is first screened for major foreign bodies, such as metal shavings, rust, dirt, and the like.
[0074] The filter may be operated as a continuous flow process, such that the incoming sides of the lumens in the filter element or elements are being substantially continuously flushed across its surface by recirculating oily water, which delays or prevents the surface becoming plugged with small oil droplets or other debris.
[0075] The products of the filter, namely filtered water and concentrated oily waste (retentate) pass to respective holding tanks for disposal, the permeate having exited through the walls of the filter element, and the concentrated oily retentate through a solenoid valve that drains the process loop on a predetermined schedule.
[0076] The concentrated oily waste, having a concentration of up to about 40% oil in emulsion, is removed for disposal or further treated on site to drop out the water from this emulsion to be returned to the process.
[0077] This quantity requiring disposal usually represents significantly less than 10% of the original raw feed liquid, even as little as 2-5% of the original feed quantity when after-processing emulsion breaking activities are carried on.
[0078] The system includes a multi-port manifold, the individual ports each having a solenoid valve for controlling the open or closed state for the port by way of a bang-bang (on/off) control.
[0079] The operation of the process is separated into discrete system functions, enabling it to be readily controlled by a central computerized control.
[0080] This controller can then control a number of such processing systems.
[0081] Individual filter modules of the multiple systems may filter different waste liquids, using respective processor loops. The different loops may all be controlled by the same logic controller and associated fluid manifold systems.
[0082] The subject processor's filter loop is very compact with an embodiment in a substantially planar arrangement. This enables the total system to be installed within a modest sized cabinet.
[0083] In one embodiment, the cabinet has a compact computerized control system which controls the system pumps as well as the manifold mounted solenoids, the manifold being mounted within the interior of the processor loop compartment.
[0084] The filter loop system is pivotally mounted, for rotational diplacement within the cabinet, to facilitate access and servicing of the system and its components, when rotated.
[0085] A second, parallel system that requires no additional space can be similarly mounted within the same cabinet compartment, to the same effect, the modules being arranged in back-to-back relation and being controlled by the same controller.
[0086] By mounting the two processing loops and modules on a vertical pivot, and with the provision of flexible connection hoses, either processing loop can be readily accessed from the front of the cabinet, for servicing purposes.
[0087] Despite the compactness of the system, a good rate of permeate flow can be achieved.
[0088] In a test plant having a module with a membrane surface area of 0.2 square meters a daily permeate flow rate of about 1200 liters per day was achieved consistently, operating with a program of three cleaning cycles per day The waste material being treated was a mixture of cutting coolants, floor wash, pressate fluids, and tumbler wastes with an average oil content of 2.5%. This processing output represents a flux rate of 6000 liters of permeate per day per square meter of membrane surface area.
[0089] For a module having a filtration element of 0.4 square meters, a daily permeate output well in excess of 2000 liters is anticipated.
[0090] While the present process is particularly directed to the separation of oil and water, it will be understood that it may well be applied to other liquid media separation.
BRIEF DESCRIPTION OF THE DRAWINGS
[0091] Certain embodiments of the invention are described by way of illustration, without limitation thereto other than as set forth in the accompanying claims, reference being made to the accompanying drawings, wherein:
[0092] [0092]FIG. 1 is a schematic diagram in frontal elevation of a system embodiment of the processing filter loop in accordance with the present invention;
[0093] [0093]FIG. 2 is a schematic diagram of the FIG. 1 embodiment, together with the associated service connections, illustrated as operating in a No Power phase of its cycle;
[0094] [0094]FIG. 3 is a plan view of a cabinet (top removed) enclosing two filtration systems in accordance with the present invention.
[0095] [0095]FIG. 4 is similar to FIG. 3, with the cabinet door in the open condition;
[0096] [0096]FIG. 5 is a diametrical cross-section of the end portion of a cross flow membrane filter module in accordance with the present invention.
[0097] [0097]FIGS. 6 through 11 are schematic process connections for operation of the FIG. 1 embodiment, under separation phase and cleaning phase operating conditions; and
[0098] FIGS. 12 - 16 are schematic process flow charts for the FIG. 1 embodiment.
DETAILED DESCRIPTION OF THE INVENTION
[0099] Referring to FIGS. 1 and 2, a separation system 10 in accordance with the present invention, representing only the processing filter loop (and excepting the programmable logic controller, solenoid manifold, chemical solution tanks, etc.) has a separation filter module 12 connected in series relation with two circulating pumps 14 , 14 , driven by electric motors 14 ′. The pumps 14 , 14 circulate the raw oil/water mix in a closed circuit by way of pipelines 17 .
[0100] A pair of unions 15 , 15 in the circulation pipelines 17 provide disconnection capability, to enable replacement of the filter module 12 , when required.
[0101] Permeate circuit connections 16 , 16 (FIG. 2) from the top and the bottom of the filter module 12 connect with a distribution manifold 18 . As well, top and bottom processor loop connections connect with manifold 18 .
[0102] Referring also to FIGS. 3 and 4, the system elements are mounted as planar assemblies each upon a planar vertical frame 20 . In FIGS. 3 and 4, two such systems 10 are mounted in back-to-back relation within a cabinet 30 . All the components of the two systems may be advantageously mounted within a single cabinet.
[0103] The two systems 10 are mounted upon a vertical-axis pivot 38 , such that one or other of the systems 10 can be exposed for ready access through the open door 32 of the cabinet 30 . The raw water and other connections are by way of flexible extended hoses (not shown), such that either of the systems 10 can be readily accessed.
[0104] In FIG. 4, the two systems are shown in course of being reversed, having been rotated 90 degrees clockwise.
[0105] Referring back to FIG. 2, a manifold 18 is delineated by way of phantom lines, including therewith the associated solenoid-controlled valves 42 through 64 , that serve the respective fluid connections.
[0106] The illustrated valve conditions are for a No Power condition, such as the switching off of the pumps 14 . Valve 44 and Valve 54 connect to a common air supply (not shown).
[0107] Three cleaning solution tanks 66 , 68 and 70 are shown. It will be understood that more or less tanks may be required, depending on the nature of the raw oily feed water.
[0108] The three cleaning solution (“Chem”) tanks 66 , 68 , and 70 are pressured up from the common air supply (not shown).
[0109] The fluid connections for the respective valves 42 through 64 are as follows: 42 —raw oily feed water supply, 44 —air for purging; 46 —purged air/water; 48 —purge cleaning solutions; 50 —common purge valve (i.e. for purge air, water, & chemical cleaning solutions, all purge lines leave the processor here); 52 —permeate out; 54 —normally open air safety valve; 56 —tap water; 58 —tap water for purging solutions; 60 , 62 , 64 —respective cleaning solutions, from tanks 66 , 68 , 70 . 60 ( 66 )=detergents; 62 ( 68 )=acids; 64 ( 70 )=spare, alternative chemicals. In operation:
[0110] Valve 42 : Introduces waste oily water to the system for processing.
[0111] Valve 44 : This valve is connected to a source of compressed air. When the processing loop needs to be evacuated of waste water this valve opens supplying air to the top of the loop which drives water out of the loop through the bottom and out through valve 50 and on to the waste holding tank.
[0112] Valve 46 : When the processing loop is empty of any water and is being filled with either tap water or waste water, air (and a small amount of water) escapes through valve 46 to the waste holding tank. Escaping air allows the process loop to fill.
[0113] Valve 48 : After each cleaning cycle, any cleaning solution that remains is removed from the module's permeate space by a flush of tap water introduced through valve 58 . Water from valve 58 travels through the permeate space of the filter module, entering at the bottom and exiting at the top before flowing through valve 48 and on to the waste holding tank.
[0114] The motion of this water can be used either to push cleaning solutions from the module after cleaning, or as a tap water flush of the module before the introduction of a succeeding cleaning chemical.
[0115] Valve 50 : Water from the bottom of the process loop leaves through valve 50 to the waste tank after valve 44 opens to introduce pressurized air to the top of the loop, which ultimately drives the water out of the loop through valve 50 and on to the waste holding tank.
[0116] Valve 56 : This valve introduces tap water to the process loop from the bottom. This is done to fill the loop with water before start up or alternately to fill the loop during a flushing sequence of a chemical cleaning cycle.
[0117] Valve 58 : This valve admits tap water into the bottom of the module to drive excess cleaning solution out the top of the module, to exit through valve 48 . The valve 58 also opens to flush the module's permeate space clean of left over chemistry after a cleaning cycle.
[0118] Valve 60 : This valve introduces cleaning chemical solution number 1 into the permeate space of the module. Tank 66 is air pressurized.
[0119] Valve 62 :_This valve introduces cleaning chemical solution number 2 into the permeate space of the module. Tank 68 is air pressurized.
[0120] Valve 64 : This valve introduces cleaning chemical solution number 3 into the permeate space of the module. Tank 70 is air pressurized.
[0121] Referring to FIG. 5, a lower portion of a filter module 12 has a cylindrical metal housing 74 with a cylindrical ceramic filter element 76 supported by way of a duplex O-ring seals 80 , 80 . The O-ring seals 80 , 80 are held in place by way of machined out shoulders 78 , 78 cut into flanges 82 , 83 . Flange 82 is welded to the cylindrical metal housing 74 . Flange 86 is a flat flange which pulls the whole assembly up when the bolts 85 , 85 (plus two more not shown) are tightened.
[0122] The annular permeate space 84 between the filter element 76 and the housing 74 receives the permeate water that has passed through the wall of filter element 76 .
[0123] An end connector 86 connects the filter module 12 to the waste water circulation pipeline 17 (FIG. 2); and a connector 88 welded to the wall of housing 74 connects the permeate space 84 with the manifold 18 (FIG. 2).
[0124] The permeate space 84 is kept to a minimum volume, to minimize the quantities of cleaning fluid required to fill it, as in a back-flushing cleaning operation.
[0125] Referring to FIG. 6, this shows the state of the system for a Power Off or a Power Failure condition, as exemplified by the respective open or closed condition of the flow control valves 42 through 64 , which connect with manifold 18 , shown schematically.
[0126] The manifold 18 is machined from suitable brass bar stock and acts as both the support for the solenoids as well as providing the appropriate routing connections between the various fluid lines that are controlled by the solenoids.
[0127] Basically, despite the complexity of the manifold, with lines coming in from outside the processor, or leaving the processor, only four lines actually connect the manifold to the process loop and module. Therefore only those four lines require the added length and flexibility to permit axial rotatation when the processor is in service or the “Back Processor” is rotated to the front of the cabinet for servicing.
[0128] In FIGS. 6 - 11 the boxed designations P 1 , P 2 , P 3 , and P 4 refer to these four points of external connection on the processor proper.
[0129] The control valves are all solenoid actuated, operating in bang-bang mode, i.e. being in either a fully open or a fully closed condition, as controlled by the computerized controller.
[0130] [0130]FIG. 7 shows the respective conditions of the manifold valves during normal processing.
[0131] [0131]FIG. 8 shows the respective valve settings during the discharge of a portion of the recirculating, concentrated oily water (retentate) from the process loop. The delineation of manifold 18 , shown in FIGS. 6 and 7, has been omitted from FIGS. 8 - 11 .
[0132] [0132]FIG. 9 shows the respective manifold valve settings for the admission of purge air to effect discharge of oily water from the process circulatory loop.
[0133] [0133]FIG. 10 shows the respective valve settings for effecting flushing of the process circulatory loop with tap water.
[0134] [0134]FIG. 11 shows the respective valve settings for effecting a tap water flush after a chemical back-flush cleaning cycle through the permeate collection circuit.
[0135] The subject system takes relatively little floor area.
[0136] In operation, the normal cycle commences with the admission of the raw feed typically by way of an air diaphragm pump (not shown), the raw feed being a mixture of water and oil emulsion, usually having a concentration of oil of about 1-2 percent. The raw feed is passed through a sieve, to remove coarse particles, including foreign objects such as rags. This sieve can be readily cleaned without interruption of the cycle of operations. The air diaphragm pump also moves water into the process loop, and applies static pressure on the system.
[0137] The oil/water retentate mixture, being concentrated in the process by the removal of up to 95 percent of the water, is then about a 40 percent oil/water mixture, which is well suited for haulage, storage and ultimate disposal, or for further concentration.
[0138] Concerning the filter element 76 , which has membrane pore sizes in the range 0.005-1.2 microns, the selection of pore size is based upon its appropriateness for the aqueous waste mix involved.
[0139] _Turning to FIGS. 6 through 11, FIG. 6 shows the state of the respective valves when power is switched off, or there is a power failure. The system is set up such that all valves except one will close in the absence of power, effectively shutting off all air or fluid movement to or from the processor. During a power off situation the only valve left in an open state is the air pressure safety valve. This is the only “Normally Open” valve in the system. When the processor is powered up, this valve closes and is held closed until there is an absence of power. With no power all other valves close, but this one now opens to receive compressed air, to drive processed permeate water backwards into the permeate space of the module. This pressurized water pushes through the filter element flowing through and protecting the membrane filter surface.
[0140] [0140]FIG. 7 shows the system component condition for normal processing.
[0141] [0141]FIG. 8 shows the system component condition when purging some of the concentrated retentate (oily waste water) from the processing loop, for subsequent disposal.
[0142] [0142]FIG. 9 shows the system component condition for admitting purging air, when purging the processing loop of retentate (oily water).
[0143] [0143]FIG. 10 shows the system component condition when flushing the process loop with tap water;
[0144] [0144]FIG. 11 shows the system condition when flushing with tap water after a chemical cleaning cycle; and,
[0145] [0145]FIGS. 12 through 16 show the operating modes for the subject process. | A practicable, compact local system is used to separate emulsified oil from water, enabling re-use or disposal to drain of most of the water. The treated water meets regulatory guidelines for safe disposal to drain. The system can separate highly emulsified oil/water mixes. It uses a ceramic cross-flow membrane filter with pore sizes in the range of 0.005 micron to 1.2 micron, operating at pressures in the range 25 to 150 psi (gauge). Removal of up to about 95% of the water can be achieved. High separation flux rates are achieved by computer controlled cleaning cycles, made practical by providing minimal permeate collection spaces downstream of the filter on the water discharge side. Two independently operable systems may share a modest cabinet. | 1 |
CROSS REFERENCE
[0001] This application claims the benefit of U.S. Patent Application No. 60/878,481, filed Jan. 3, 2007, which is incorporated herein by reference.
TECHNICAL FIELD
[0002] The technical filed relates generally to coatings to inhibit formation of deposits on surfaces which come into elevated temperature contact with hydrocarbons.
BACKGROUND
[0003] Hydrocarbon fluids which come into contact with metal or alloy surfaces at elevated temperatures tend to form deposits. These deposits are problematic for systems such as gas turbine engines which utilize fuels and lubricants including one or more hydrocarbon fluids such as hydrocarbon liquids, vapors, particles or combinations thereof. Hydrocarbon fluids may include sulfur and other heteroatom compounds such as oxygen and nitrogen. Hydrocarbon fluids may also include a number of additives such as antioxidants, metal deactivators, antifreeze, and/or anti-corrosion additives. During gas turbine engine operation, oxidative, thermal and catalytic degradation products of hydrocarbons and heteroatom compounds may produce undesired deposits. Oxidative degradation can lead to the formation of large polymers and gum/lacquer like deposits. Thermal degradation can lead to the formation of soot-like and pyrolytic deposits. Catalytic degradation can lead to the formation of filamentous and laminar graphite-like deposits. Deposits can be formed by metal-assisted decomposition of hydrocarbons, and condensation and polymerization of the hydrocarbon species can give rise to large polyaromatic hydrocarbons (PAHs), carbonaceous solids, and solid carbon. Solid deposits also include metal sulfides formed due to the interaction or reaction of metal and alloy surfaces with sulfur compounds present in hydrocarbon fluids. Deposits formed by the foregoing and other mechanisms create a variety of problems for metal and alloy surfaces which come into contact with hydrocarbon fluids at elevated temperatures. For example, fuel injectors, fuel lines and other components of fuel systems can experience valve malfunctions, injector plugging, injector wall fouling and other problems due to deposits. Lubrication systems may experience clogging of vent pipes and other components by deposits which can impede flow of oil through the system and prevent cool down of bearings and other hot surfaces. These and other problems are expensive and can result in inefficiency, malfunction, and even failure.
SUMMARY
[0004] Certain embodiments are unique coatings. Other embodiments include apparatuses, articles, and components including such coatings and, systems and methods for providing such coatings. Further embodiments, forms, objects, features, advantages, aspects, and benefits shall become apparent from the following description and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] FIG. 1 is a sectional view of a portion of a coated substrate.
[0006] FIG. 2 is a sectional view of a portion of a coated substrate.
[0007] FIG. 3 is a flow diagram of operations in a substrate coating method.
[0008] FIG. 4 is a schematic diagram of a system for performing a coating operation.
[0009] FIG. 5A is a field emission scanning electron microscopy image of an uncoated substrate surface.
[0010] FIG. 5B is a field emission scanning electron microscopy image of a coated substrate surface.
[0011] FIG. 6 is a graph illustrating temperature programmed oxidation profiles of deposits on coated and uncoated substrates.
DETAILED DESCRIPTION
[0012] For the purposes of promoting an understanding of the principles of the invention, reference will now be made to the embodiments illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the illustrated embodiments, and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates.
[0013] With reference to FIG. 1 , there is illustrated a portion of a substrate 110 having a surface 111 , a first metal oxide coating layer 120 , and a second metal oxide coating layer 130 which includes a number of stable carbon species 140 . Substrate 110 is preferably a metal or alloy material, for example, but not limited to, stainless steels, metals including Al, Co, Cr, Fe, Mo, Ni, Ti, W and alloys thereof, and other metals and alloys employed in gas turbine engines. First metal oxide coating layer 120 is preferably a layer of Cr 2 O 3 which has been formed on surface 111 by heating substrate 110 to oxidize chromium present in substrate 110 . It is also contemplated that first metal oxide coating layer 120 could include one or more other types of metal oxides including, for example, oxides of the metals and alloys described above and/or formed in other manners such as those described below in connection with FIG. 3 .
[0014] Second metal oxide coating layer 130 is preferably a layer of Al 2 O 3 which has been formed on first metal oxide coating layer 120 by a chemical deposition technique, preferably by a chemical vapor deposition technique, most preferably by a metal organic chemical vapor deposition technique. In additional embodiments, second metal oxide coating layer 130 could include a variety of other materials, for example, SiO 2 , TiO 2 , ZrO 2 , Cr 2 O 3 , Ta 2 O 5 , WO 2 , MoO 2 , a ternary oxide of Aluminum-Magnesium, a ternary oxide of Aluminum-Potassium, and combinations thereof with one another or with Al 2 O 3 . Further embodiments also contemplate that other chemical deposition techniques such as pulsed laser deposition, physical vapor deposition, electron beam physical vapor deposition, effusive chemical vapor deposition and others could be used.
[0015] Stable carbon species 140 are preferably present in second metal oxide coating layer 130 and are preferably formed through the partial decomposition of a metal organic precursor that leaves carbon associated with the metal oxide coating. Preferred stable carbon species include C—C, C—O, C═O, and/or COOR as constituents which may be present in a variety of forms and bonded with a variety of additional molecular constituents. A number of variations on the embodiment illustrated in FIG. 1 are contemplated. For example, first metal oxide coating layer 120 might be absent, first metal oxide coating layer 120 and/or second metal oxide coating layer 130 might have different compositions or be formed by different techniques from those described above, and stable carbon species might be present in differing quantities or might be absent.
[0016] With reference to FIG. 2 , there is illustrated a portion of a substrate 210 having a surface 211 , a first metal oxide coating layer 220 , and a second metal oxide coating layer 230 which includes a number of stable carbon species 240 , and platinum layer 250 . Substrate 210 is preferably a metal or alloy material, for example, but not limited to, stainless steels, metals including Al, Co, Cr, Fe, Mo, Ni, Ti, W and alloys thereof, and other metals and alloys employed in gas turbine engines. First metal oxide coating layer 220 is preferably a layer of Cr 2 O 3 which has been formed on surface 211 by heating substrate 210 to oxidize chromium present in substrate 210 . It is also contemplated that first metal oxide coating layer 220 could include one or more other types of metal oxides including, for example, oxides of the metals and alloys described above and/or formed in other manners such as those described below in connection with FIG. 3 .
[0017] Second metal oxide coating layer 230 is preferably a layer of Al 2 O 3 which has been formed on first metal oxide coating layer 220 by a chemical deposition technique, preferably by a chemical vapor deposition technique, most preferably by a metal organic chemical vapor deposition technique. In additional embodiments, second metal oxide coating layer could include a variety of other materials, for example, SiO 2 , TiO 2 , ZrO 2 , Cr 2 O 3 , Ta 2 O 5 , WO 2 , MoO 2 , a ternary oxide of Aluminum-Magnesium, a ternary oxide of Aluminum-Potassium, and combinations thereof with one another or with Al 2 O 3 . Further embodiments also contemplate that other chemical deposition techniques such as pulsed laser deposition, physical vapor deposition, electron beam physical vapor deposition, effusive chemical vapor deposition and others could be used.
[0018] Platinum coating layer 250 is preferably formed on second metal oxide coating layer 230 by a metal organic chemical vapor deposition technique, but could also be formed using other techniques such as the chemical deposition techniques described above. Stable carbon species 240 are preferably disposed in second metal oxide coating layer 230 through the partial decomposition of a metal organic precursor that leaves carbon associated with the metal oxide coating. Preferred stable carbon species include C—C, C—O, C═O, and/or COOR as constituents which may be present in a variety of forms and bonded with a variety of additional molecular constituents. A number of variations on the embodiment illustrated in FIG. 2 are contemplated. For example, first metal oxide coating layer 220 might be absent, first metal oxide coating layer 220 and/or second metal oxide coating layer 230 might have different compositions or be formed by different techniques from those described above, platinum coating layer might be of a different catalytic material or absent altogether, and stable carbon species might be present in differing quantities or distributions or might be absent.
[0019] The coated substrates described above in connection with FIGS. 1 and 2 are preferably used to inhibit or prevent the formation of deposits on surfaces which come into contact with hydrocarbons at high temperatures. In certain preferred embodiments, a coated substrate such as described above is provided in a fuel system for a gas turbine engine. In these embodiments, the surfaces of fuel pipes, fuel passageways and/or injector nozzles of gas turbine engine fuel systems which would otherwise be exposed to fuel or other hydrocarbon fluids at elevated temperatures are provided with coatings such as those described above. In other preferred embodiments, a coated substrate such as described above is provided in a lubrication system for a gas turbine engine. In these embodiments, the surfaces of gas turbine engine components that would otherwise be exposed to lubricants or other hydrocarbon fluids are provided with coatings such as those described above. In further embodiments, a variety of additional substrate surfaces which would otherwise come into contact with hydrocarbon fluids at elevated temperatures are provided with coatings such as those described above. The surfaces to be coated often have complex geometries, for example, the fuel passageways of gas turbine engine fuel pipes and fuel injectors. The coatings described above can be provided on complex geometries by methods and techniques such as the preferred methods and techniques described below.
[0020] With reference to FIG. 3 there is illustrated a flow diagram 300 of operations of a preferred method of coating a substrate. Flow diagram 300 begins at operation 310 where a substrate surface is provided. The substrate surface could be any metal or alloy surface, for example, stainless steels, metals including Al, Co, Cr, Fe, Mo, Ni, Ti, W and alloys thereof, and other metals and alloys employed in gas turbine engines. Flow diagram 300 then proceeds to operation 320 where heat treatment of the substrate surface occurs in an oxidative atmosphere. The heat treatment of a stainless steel substrate preferably occurs at temperatures between 300-500° C. The heat treatment is applied for a time and temperature sufficient to cause chromium in the stainless steel substrate to diffuse toward the substrate surface and form a protective chromium oxide rich layer. In the case of substrate materials not including chromium, an oxide rich layer can be formed by oxidation of other metal, for example, heat treatment of Ni-based superalloys at about 800° C. can produced oxide rich surface layers such as Al 2 O 3 , TiO 2 , Cr 2 O 3 , Fe 2 O 3 and NiO. The required time and temperature will depend upon the composition of the substrate, the nature of the oxidative atmosphere, and other factors. This layer may provide improved diffusion stability of the coating, enhance bonding of an alumina coating subsequently applied to the substrate, and prevent refractory transition elements such as molybdenum, vanadium and tungsten from diffusing into the coating layer. When combined with a subsequently applied coating layer, the multi-layer coatings may also provide better coverage of the surface compared to a single coating layer. Forming an oxide rich layer by heat treatment can also provide a multi-material and/or multi-layer coating without requiring two metal organic chemical vapor deposition operations. It should be appreciated, however, that not every embodiment need exhibit the foregoing characteristics, and that in certain embodiments the heat treating operation may be omitted or replaced with alternate processes.
[0021] At operation 330 , a metal oxide coating is applied to the substrate surface most preferably by using a metal organic chemical vapor deposition technique. In a preferred embodiment, aluminum 2,4 pentanedionate is used at the metal organic precursor to form an aluminum oxide coating layer. It should be appreciated, however, that a variety of other precursor materials can be used, and that a variety of other oxide coating layers can be provided from a variety of other metal organic precursors. Further details of a system for metal organic chemical vapor deposition are described below in connection with FIG. 4 . It should also be appreciated that the formation of an oxide layer can be accomplished using a variety of other techniques, such as pulsed laser deposition, physical vapor deposition, electron beam physical vapor deposition, effusive chemical vapor deposition and others.
[0022] At operation 340 a controlled decomposition or reaction of the metal organic precursor is performed to incorporate stable carbon species into the oxide layer being formed by metal organic chemical vapor deposition. In certain preferred embodiments oxygen is introduced and/or reacted with one or more organometallic compounds. By varying the temperature, pressure, carrier gas flow rate and duration of coating the nucleation and subsequent growth of thin films on the metal substrate can be controlled so as to obtain metal oxide coatings with varying thickness, phase properties and variant physical and chemical properties, including the incorporation of stable carbon species in the coating. The presence of these carbon species can stabilize acid sites on metal oxide surfaces and inhibit the diffusion of carbon containing species through the oxide, however, these characteristics need not be present in all embodiments.
[0023] At operation 350 , a thin layer of platinum is applied preferably by using a metal organic chemical vapor deposition system such as that described below in connection with FIG. 4 , or by one of the alternative techniques described above. In a preferred embodiment, platinum 2,4 pentanedionate is used at the metal organic precursor to form the platinum layer. The layer of platinum can serve as a barrier that prevents substrate metal migration, and can provide catalytic activity for the oxidation of carbonaceous deposits that might be formed on the coated substrate. In a preferred embodiment where a coating is formed in the fuel system of a gas turbine engine, any carbonaceous solids formed in one engine cycle can be removed upon engine shut down when the surface of the metal is still exposed to a high temperature and an oxidative environment but without any inflow of hydrocarbons. In this embodiment the coating exhibits a self-cleaning characteristic. It should be understood that these characteristics need not be present in all embodiments, and that certain embodiments may omit application of a layer of platinum. It should also be understood that a catalyst other than platinum can be used.
[0024] At operation 360 , oxygen and/or steam treatment of the coated substrate are performed. Treatment with oxygen and/or steam may cause further oxidation which may aid in passivation of any active sites present on the coated surface and may further improve the quality of the coating leading to substantial elimination or improved minimization of carbon deposits which would otherwise tend to form on the coated surfaces. It should be understood that these characteristics need not be present in all embodiments, and that certain embodiments may omit the oxygen and/or steam treatment.
[0025] With reference to FIG. 4 there is illustrated a metal organic chemical vapor deposition system 400 useful for applying coatings to a substrate. Gas input 410 provides a carrier gas such as argon to the system. Mass flow controllers 420 A, 420 B, 420 C, and 420 D control passage of the carrier gas through the system. Mass flow controllers 420 A, 420 B, and 420 C control gas flow to bubblers 420 A, 420 B, and 420 C, respectively. Output from the mass flow controllers can be regulated by valves (not numbered). Bubblers 420 A, 420 B, and 420 C heat liquid metal organic precursor materials to provide metal organic precursor vapors which are transported through the system by the carrier gas. In a preferred embodiment one bubbler provides aluminum 2,4 pentanedionate vapor for forming an aluminum oxide coating and another bubbler provides platinum 2,4 pentanedionate vapor for forming a platinum coating layer. Output from the bubblers is regulated by valves (not numbered). The output from bubblers passes through heated lines (not numbered). When the output from multiple bubblers is to be mixed, this operation can occur in mixing chamber 440 which can receive the output of each of the bubblers 430 A, 430 B, and 430 C. The output of mixing chamber 440 passes through needle valve 460 and to an environment including a substrate to be coated 472 , which is contained in furnace 470 which is controlled by temperature controller 471 and whose pressure can be monitored by pressure transducer 473 . Argon from mass flow controller 420 D and oxygen from mass flow controller 450 can also be introduced after mixing chamber 440 and before needle valve 440 . In furnace 470 the decomposition of the metal organic precursor is controlled by varying the coating temperature, pressure, time, carrier gas flow-rate and concentration of precursor vapors in the carrier gas. Furnace 470 outputs to a cleaning system 480 which includes an LN 2 trap, a molecular sieve, a throttle valve, a pump and a vent.
[0026] With reference to FIG. 5A there is illustrated a filed emission scanning electron microscopy image of an uncoated stainless steel SS316 substrate. With reference to FIG. 5B there is illustrated a filed emission scanning electron microscopy image of a stainless steel SS316 substrate with an aluminum oxide coating. Measurements of the coating thickness for two samples are shown in Table 1 below.
[0000] TABLE 1 Thickness of CVD Alumina Coatings Measured by Ellipsometry Thickness (nm) Sample name Min. Max. Al 2 O 3 coating on SS316-1 34 133.5 Al 2 O 3 coating on SS316-2 62 164.3 FIG. 5A shows the roughness of the uncoated SS316 substrate surface. FIG. 5B shows that the alumina coating applied to this surface is made of more or less uniform spherical structures and that the coating reproduces the surface finish of the underlying substrate to a large extent. These results shown above in Table 1 vary along the length of the substrate as well as between two samples coated under the same conditions. This variation can be explained by the surface roughness of the uncoated substrates which is also reflected in the coating. Since the accuracy of ellipsometry depends upon samples that are perfectly flat and fully reflective, and the samples used in his study do not have these properties, measurement error accounts for a large degree of the variation in coating thickness.
[0027] The results of an X-ray photoelectron spectroscopy (XPS) characterization are given below in Table 2.
[0000]
TABLE 2
XPS Determined Chemical Composition of Alumina Coated
Surfaces of Two SS316 Substrates Coated Under the
Same Conditions
Surface Chemical Composition (relative atomic %)
Sample name
Al
C
O
N
B
S
Na
Zn
F
Al 2 O 3 on SS316-1
20.2
30.7
46.6
0.4
0.6
0.3
0.2
0.0
1.0
Al 2 O 3 on SS316-2
26.7
18.1
53.1
0.3
0.2
0.7
0.6
0.2
0.1
[0028] In one embodiment the surface chemical composition determined by XPS characterization and expressed in relative atomic percent includes about 18% carbon. In another embodiment the surface chemical composition determined by XPS characterization and expressed in relative atomic percent includes about 30% carbon. In additional embodiments the surface chemical composition determined by XPS characterization and expressed in relative atomic percent includes about 10% or more carbon. In additional embodiments the surface chemical composition determined by XPS characterization and expressed in relative atomic percent includes about 15% or more carbon. In additional embodiments the surface chemical composition determined by XPS characterization and expressed in relative atomic percent includes about 18% or more carbon. The average Al:O ratio was 0.45. The decrease in ratio of alumina to oxygen compared to pure Al 2 O 3 is attributed to the presence of significant amounts of carbon species (from the precursor) and other minor impurities in the coating.
[0029] Curve fitting results of the C 1s spectra obtained from the XPS analysis of the alumina coatings gave preliminary information on the nature of the carbon species present in the coatings. These results are shown in Table 3.
[0000] TABLE 3 Nature and Relative Atomic Ratios of Carbon Species Present in the Coating Nature of Carbon Species (relative atomic %) Sample name C—C C—O C═O COOR Al 2 O 3 on SS316-1 59.0 12.2 15.0 12.2 Al 2 O 3 on SS316-2 63.8 15.6 4.1 15.0
The effectiveness of the coating was tested by comparing the nature and amount of carbonaceous solids formed on the coated surface with that of an uncoated SS316 surface. The solid deposits on the two surfaces were formed by stressing Jet A in a ¼-inch OD flow reactor at 470° C. and 500 psi for 5 hrs. The fuel flow rate was maintained at 4 ml/min. Temperature Programmed Oxidation (TPO) was used to characterize the carbonaceous solids on the basis of their structure and oxidation reactivity. For this purpose, the deposited samples were placed in a quartz boat and heated from 100 to 900° C. under a flowing stream of O 2 , the flow rate of which was maintained at 750 cc/min.
[0030] FIG. 6 illustrates the TPO profiles of the carbonaceous deposits formed on both bare SS316 and coated surfaces. The y-axis in the plot on FIG. 6 represents arbitrary units proportional to the amount of carbon dioxide evolution. From the comparison of the two profiles, it is evident that the alumina coating nearly eliminates solid formation. Inspection of the foils after thermal stressing also showed that the coating was intact at least up to 500° C. Similar coating were also found to be effective against the oxidative degradation of jet fuel as well as synthetic ester based lubricating oils.
[0031] Certain embodiments are coatings for a hydrocarbon fluid containment component including a first metal oxide layer on the component, and a second metal oxide layer on the first metal oxide layer, where the second metal oxide layer contains stable carbon species. Some embodiments further include a platinum layer on the second metal oxide layer. In some embodiments the stable carbon species include carbon constituents selected from the group consisting of C—C, C—O, C═O, and COOR. In some embodiments the second metal oxide layer includes at least one of Al 2 O 3 , SiO 2 , TiO 2 , ZrO 2 , Cr 2 O 3 , Ta 2 O 5 , WO 2 , MoO 2 , a ternary oxide of Aluminum-Magnesium, and a ternary oxide of Aluminum-Potassium. In some embodiments the component is a gas turbine engine fuel containment component. In some embodiments the second metal oxide layer consists essentially of stable carbon species and at least one of Al 2 O 3 , SiO 2 , TiO 2 , ZrO 2 , Cr 2 O 3 , Ta 2 O 5 , WO 2 , MoO 2 , a ternary oxide of Aluminum-Magnesium, a ternary oxide of Aluminum-Potassium, and a combination thereof with the balance being impurities. In some embodiments the stable carbon species are derived from partial decomposition of one or more organometallic compounds. In some embodiments the stable carbon species are derived from partial decomposition of aluminum 2,4-pentanedionate. In some embodiments the coating has a composition measured by XPS characterization and expressed in relative atomic percent of about 10% or more carbon. In some embodiments the coating has a composition measured by XPS characterization and expressed in relative atomic percent of about 18% or more carbon. In some embodiments the first metal oxide layer is formed by heating the component in an oxidative environment. In some embodiments the second metal oxide layer is formed by chemical vapor deposition. In some embodiments the carbon constituents of the stable carbon species consist essentially of C—C, C—O, C═O, COOR, or a combination thereof.
[0032] Certain embodiments are methods of coating a hydrocarbon fluid containment article including providing a hydrocarbon fluid containment article having a surface, providing a first metal oxide layer on the surface, and providing a second layer on the first metal oxide layer, the second layer including metal oxide and stable carbon species. Some embodiments further include providing a platinum layer on the second layer. In some embodiments the hydrocarbon fluid containment article is a gas turbine engine component. In some embodiments providing a first metal oxide layer includes oxidizing the surface of the containment article. In some embodiments providing a second layer includes performing a chemical vapor deposition. In some embodiments providing a second layer includes partial decomposition of an organometallic precursor effective to deposit metal oxide and stable carbon species on the first metal oxide layer. Some embodiments further include treating the article with steam, or oxygen, or both after the providing a second layer on the first metal oxide layer. Some embodiments further include treating the article with steam, or oxygen, or both after the providing a platinum layer on the second metal oxide layer. In some embodiments the metal oxide of the second layer is Al 2 O 3 , SiO 2 , TiO 2 , ZrO 2 , Cr 2 O 3 , Ta 2 O 5 , WO 2 , MoO 2 , a ternary oxide of Aluminum-Magnesium, a ternary oxide of Aluminum-Potassium, or a combination thereof.
[0033] Certain embodiments are coating systems for a substrate including a first coating on the substrate, the first coating including metal oxide, a second coating on the first coating, the second coating including metal oxide and stable carbon species, and a third coating on the second coating the third coating including a hydrocarbon catalyst. In some embodiments the first coating consists essentially of metal oxide. In some embodiments the first coating is formed by oxidizing a constituent of the substrate. In some embodiments the first coating consists essentially of Cr 2 O 3 . In some embodiments the second coating consists essentially of metal oxide and stable carbon species with the balance being impurities. In some embodiments the second coating is formed by partial decomposition of an organometallic precursor effective to provide metal oxide and stable carbon species. In some embodiments the partial decomposition of an organometallic precursor is includes reacting oxygen with the organometallic precursor. In some embodiments the stable carbon species are effective to stabilize acid sites in the coating system. In some embodiments the stable carbon species are effective to inhibit diffusion of other carbon containing species through the coating system. In some embodiments the hydrocarbon catalyst includes platinum or palladium. In some embodiments the hydrocarbon catalyst includes a transition metal. In some embodiments the hydrocarbon catalyst is platinum.
[0034] While the invention has been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character, it being understood that only the preferred embodiments have been shown and described and that all changes and modifications that come within the spirit of the inventions are desired to be protected. It should be understood that while the use of words such as preferable, preferably, preferred or more preferred utilized in the description above indicate that the feature so described may be more desirable, it nonetheless may not be necessary and embodiments lacking the same may be contemplated as within the scope of the invention, the scope being defined by the claims that follow. In reading the claims, it is intended that when words such as “a,” “an,” “at least one,” or “at least one portion” are used there is no intention to limit the claim to only one item unless specifically stated to the contrary in the claim. When the language “at least a portion” and/or “a portion” is used the item can include a portion and/or the entire item unless specifically stated to the contrary. | Certain embodiments are unique coatings. Other embodiments include apparatuses, articles, and components including such coatings and, systems and methods for providing such coatings. Further embodiments, forms, objects, features, advantages, aspects, and benefits shall become apparent from the following description and drawings. | 2 |
BACKGROUND OF THE INVENTION
The present invention relates to thin-film field-effect transistors and, more particularly, to a novel method for fabricating a self-aligned thin-film field-effect transistor (FET) on a transparent substrate, such as glass and the like.
A conventional thin-film field-effect transistor (FET) which is fabricated without using a self-alignment technique can result in a transistor structure with the source and drain electrodes misaligned relative to the gate electrode, i.e., the source electrode, the drain electrode or both can overlap the gate electrode either an excessive distance or too short a distance and cause adverse device performance. An overlap that is excessive causes a large source/drain-to-gate (S/D-G) capacitance and the larger S/D-G capacitance causes higher transistor noise and lag in imagertype devices using thin-film FETs as switching elements. Increased S/D-G capacitance may also contribute to offset-voltage errors in liquid crystal display (LCD) devices when individual picture elements (pixels) are switched between an operative and an inoperative state; the charge that remains in the S/D-G capacitance when the pixel is turned-off may have to be compensated to actually switch the pixel to the inoperative state. The compensating voltage required will be determined by the S/D-G capacitance and may vary from one pixel to another in a LCD device if the S/D-G capacitance varies.
Typically, the S/D-G overlap is designed to be larger than necessary to allow for photolithographic alignment errors and to ensure a sufficiently adequate overlap width to provide an acceptable contact or on-resistance. A S/D-G overlap width shorter than an optimum value may also cause the saturation drain current of the FET to fluctuate outside of acceptable limits. Thus, it is desirable to control the overlap between the S/D electrodes and the gate electrode to an optimum width that is neither too long nor too short.
It is accordingly a primary object of the present invention to provide a novel method for fabricating a self-aligned thin-film transistor which is not subject to the foregoing disadvantages.
It is another object of the present invention to provide a novel method for fabricating a self-aligned thin-film transistor which controls the overlap width of the gate electrode with each of the source and drain electrodes to an optimum distance.
These and other objects of the invention, together with features and advantages thereof, will become apparent from the following detailed specification when read with the accompanying drawings in which like reference numerals refer to like elements.
SUMMARY OF THE INVENTION
In accordance with the invention, a method for fabricating self-aligned thin-film transistors (TFTs) includes the steps of: forming an opaque gate electrode on a principal surface of a transparent substrate; depositing a first layer of insulation material (such as silicon nitride (SiN x ), silicon oxide (SiO x ) and the like) on the principal substrate surface and over the gate electrode; depositing a layer of semiconductor material on the first insulation layer; depositing a second layer of insulation material on the semiconductor layer; depositing a layer of photoresist on the second insulation layer; exposing a back-side substrate surface, opposite to the principal substrate surface, to ultra-violet (UV) light for a selected duration, to cause exposure of at least a portion of the photoresist, corresponding substantially to an area outside of the gate electrode shadow; removing at least the exposed photoresist to leave a remaining photoresist portion and to expose a segment of the second insulation layer which is not covered by the remaining photoresist portion; selectively etching the second insulation layer segment, to leave a remaining second insulation layer segment, under the remaining photoresist portion, and to expose a portion of the semiconductor layer not covered by the remaining second insulation segment, and with the remaining second insulation segment aligned with the gate electrode and narrower than the gate electrode by a selected overlap distance on each side thereof; removing the remaining photoresist portion; depositing a layer of doped semiconductor material on the exposed semiconductor portion and over the remaining second insulation segment; depositing a layer of conductive material on the doped semiconductor material; depositing a planarization layer of photoresist or the like on the conductive layer; non-selectively etching the planarization layer, to form a via opening therein and to expose at least a portion of a top surface of the conductive layer through the via opening; and selectively etching the exposed conductive layer portion and the doped semiconductor layer using the etched planarization layer as a mask, to form self-registered source and drain electrodes from the etched conductive layer, which each overlap the gate electrode the selected overlap distance.
The selected distance may be controlled by the following process variables, either individually or in any combination: the intensity and duration of the UV exposure of the photoresist during the back-side exposing step; overdevelopment of the photoresist when the exposed photoresist is removed to leave the remaining photoresist portion; and/or over-etching the second insulation layer segment, to undercut the remaining photoresist portion and to reduce the width of the remaining second insulation layer segment.
In an alternate embodiment, the exposed semiconductor portion may be patterned before depositing the doped semiconductor layer, or the doped semiconductor layer may be deposited, and then both the exposed semiconductor portion and doped semiconductor layer can be patterned in the same mask operation, to minimize the area of semiconductor material under the conductive layer and to provide additional area on the substrate for other components, such as pixel electrodes and the like.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1A-1G are cross-sectional, side elevation views of the steps employed in the thin-film transistor (TFT) fabrication method in accordance with one embodiment of the present invention.
FIGS. 2A-2C are cross-sectional, side elevation views of the steps employed in the TFT fabrication method in accordance with another embodiment of the present invention.
FIGS. 3A-3C are cross-sectional, side elevation views of the steps employed in the TFT fabrication method in accordance with a further embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring initially to FIG. 1A, a gate electrode 10 is formed on a principal surface 12 of a substrate 14, formed of an insulative transparent material, such as glass and the like. The gate electrode may be a single conductive layer of a metal, such as titanium (Ti), chromium (Cr), tungsten (W), aluminum (Al) and the like, or the gate electrode may be a multilayer structure, such as titanium over molybdenum (Ti/Mo), titanium over aluminum (Ti/Al), chromium over aluminum (Cr/Al), chromium over molybdenum (Cr/Mo) and the like, to provide good adhesion to substrate 14 and low electrical resistance. The side edges 10a and 10b of gate electrode 10 are preferably tapered by known wet or dry etching techniques to improve the step coverage, over the gate electrode edges, of subsequently deposited layers of material. Gate electrode 10 preferably has a thickness "t" between about 100 nm and about 500 nm.
A first layer 16 of insulation material having a thickness of about 200 nm to about 600 nm is deposited on principal substrate surface 12 and over gate electrode 10(FIG. 1B); a layer 18 of semiconductor material, such as intrinsic amorphous silicon (i-Si), amorphous germanium (aGe), polycrystalline semiconductor material or the like, is deposited on first insulation layer 16 to a thickness of about 50 nm by a known technique, such as plasma enhanced chemical vapor deposition (PECVD) and the like. A second insulation layer 20 having a thickness of about 200 nm to about 600 nm is deposited over semiconductor layer 18. The first and second insulation layer may be formed of one or more layers of a silicon nitride (SiN x ), a silicon oxide (SiO x ), a silicon nitrate (SiN x O y ) or other suitable dielectric material deposited by known techniques, such as PECVD and the like.
In accordance with the present invention, as seen in FIG. 1B, a layer of positive photoresist material 22 is deposited over second insulation layer 20. Ultra-violet (UV) radiation (indicated by arrows 24) is applied to the backside surface 25 of substrate 14, opposite to principal substrate surface 12, and passes through substrate 14 and layers 16,18 and 20 to expose a portion 22a of the photoresist corresponding substantially to an area (indicated by broken lines 26a and 26b in FIG. 1B) outside of the gate electrode edges. The photoresist portion 22b between broken lines 26a and 26b is effectively within the shadow of gate electrode 10 and does not receive much UV exposure, depending upon the exposure time. The back-side UV exposure occurs for a selected duration to cause overexposure of photoresist layer 22, so that photoresist portion 22b will be exposed a selected distance 28 within each of gate electrode edges 10a and 10b, bounded respectively by broken line pairs 26a and 30a, and 26b and 30b.
As seen in FIG. 1C, after UV exposure of photoresist layer 22, the exposed photoresist is developed and removed, to leave a remaining photoresist portion 32. The exposed photoresist may be overdeveloped, either in addition to the UV overexposure or alternatively thereto, to further reduce the width of the remaining photoresist portion 32 and to control selected overlap distance 28. Selected distance 28 is preferably about 1 micron to about 2 microns.
Referring now to FIG. 1D, those portions of second insulation layer 20 not masked by photoresist are removed by known etching techniques, after removing the exposed photoresist. If second insulation layer 20 is SiN x or SiO x , it may be etched, for example, by buffered hydrofluoric acid (BHF) or hydrofluoric acid (HF). Second insulation layer 20 may, in accordance with the present invention, be over-etched to undercut remaining photoresist portion 32 to reduce the width of remaining second insulation segment 34 and to further control selected overlap distance 28. Selected distance 28 may then be controlled by the above described process variables, namely, (1) overexposure of the resist, (2) overdevelopment of the resist and (3) over-etching second insulation layer 20; these three process variables may be applied either individually or in combination to control selected distance 28. Remaining photoresist portion 32 is removed after second insulation layer 20 is etched.
In some applications, such as x-ray, optical or charged particle imagers or liquid crystal display (LCD) devices, it is desirable to pattern semiconductor layer 18 before the source/drain (S/D) metallization layer is deposited, to minimize the semiconductor material area under the S/D metallization and to provide additional area on the substrate for other components, such as pixel electrodes and the like. Semiconductor layer 18 may be patterned at this point in the fabrication process or after a doped semiconductor layer 36 is deposited, in which case both layers 18 and 36 will be etched in the same masking step; both of these alternative embodiments of the present invention will be described in more detail hereinafter.
If it is not desirable or necessary to pattern semiconductor layer 18, a S/D metallization layer 38 is deposited over doped semiconductor layer 36 (FIG. 1E). Doped semiconductor layer 36 is preferably of n+ type conductivity, as provided by phosphorous doped amorphous silicon, and is deposited to a thickness between about 10 nm and about 50 nm. Layer 36 thus forms a contact between the S/D metallization layer 38 and underlying semiconductor layer 18. The S/D metallization may be a contact metal, such as molybdenum (Mo), chromium (Cr) and the like, deposited by sputtering or other known methods to a thickness between about 100 nm and about 500 nm.
As shown in FIG. 1F and in accordance with another aspect of the present invention, a layer 40 of planarization material, such as photoresist material and the like, is deposited substantially completely over the entire wafer. Planarization layer 40 is then non-selectively etched back using a planarization etch, such as a reactive ion etch (RIE) or the like. In a presently preferred embodiment, planarization layer 40 is dry etched to expose a top portion 41 of S/D metallization layer 38 (FIG. 1G); exposed S/D metallization layer 38 and doped semiconductor layer 36 may then be selectively etched, using the patterned planarization layer as a mask, until a top portion 42 of remaining second insulation segment 34 is exposed (FIG. 1H). The remainder of planarization layer 40 may then be stripped (FIG. 1I). Etched layers 36 and 38 form self-registered source and drain electrodes 38a and 38b, which each respectively overlap gate electrode 10 by selected distance 28 (FIG. 1I); selected distance 28 is chosen to provide minimum S/D-G capacitance and acceptable contact resistance. S/D metallization layer 38 may be further patterned (not shown) subsequent to the step shown in FIG. 1I, or alternatively, layer 38 may be patterned prior to the deposition of planarization layer 40 (FIG. 1F), as desired according to the application of the FET device.
Since selected overlap distance 28 is preferably small to reduce S/D-to-gate capacitance, achieving a low contact resistance becomes a concern. An advantage of the method of the present invention is that semiconductor layer 18 can be made thin so that the voltage drop due to space charge limited current flow across semiconductor layer 18 is minimized; therefore, overlap distances less than about 1 micron should still provide low contact resistance and adequate FET performance.
In accordance with an alternate embodiment of the present invention, after etching second insulation layer 20 (FIG. 1D), semiconductor layer 18 may be patterned to make room on the substrate for the formation of other devices and components, such as pixel electrodes and the like. Referring to FIG. 2A, a second layer 44 of photoresist material is deposited over semiconductor layer 18 and remaining second insulation segment 34. Substrate 14 is again exposed to UV light 24 on back-side surface 25; the UV light passes through substrate 14 and layers 16 and 18 to expose second photoresist layer 44. Again, gate electrode 10 blocks some of the UV light so that only a portion of second photoresist layer 44 is exposed outside of an area corresponding substantially to gate electrode edges 10a and 10b. The exposed second photoresist layer portion is removed by developing the photoresist (FIG. 2B). The exposure time and development time of photoresist layer 44 is much less than the exposure and development time of photoresist layer 22 when second insulation layer 20 is patterned to form remaining photoresist portion 32 (FIG. 1C); the shorter exposure and development time produces a wider remaining photoresist portion 46 (FIG. 2B). Semiconductor layer 18 is then selectively etched, using remaining photoresist portion 46 as a mask, with a reactive ion etchant to minimize undercutting of the photoresist. Etching the semiconductor material not only provides additional area on the substrate surface, but also minimizes the semiconductor material or silicon under the S/D metallization which can trap carriers and increase lag and noise in devices such as imagers and the like.
Photoresist portion 46 is removed and doped amorphous semiconductor layer 36 is deposited over remaining second insulation layer segment 34, patterned semiconductor layer 18 and on first insulation layer 16 (FIG. 2C). The fabrication process will then continue as described with respect to FIGS. 1E-1G.
In a further embodiment of the present invention, as shown in FIG. 3A-3C, doped semiconductor layer 36 may be deposited over both remaining second insulation segment 34 and semiconductor layer 18, and both semiconductor layer 18 and layer 36 may be patterned (FIG. 3A). Second photoresist layer 44 is then deposited over doped semiconductor layer 36 and UV light 24 is directed on backside surface 25 of substrate 14 to expose portions of photoresist layer 44 that are not within the shadow of gate electrode 10. The UV exposure time and the development time of photoresist layer 44 should be less than the exposure and development time of photoresist layer 22 to provide a wider remaining resist portion 46 (FIG. 3B). Doped semiconductor layer 36 and amorphous semiconductor layer 18 are then etched to form an island structure 50 (FIG. 3C), which may be desirable for some applications to provide additional area on the substrate surface and to minimize the area of semiconductor material under conductive layer 38. The fabrication method would then proceed as discussed with respect to FIGS. 1E-1G.
Depositing doped semiconductor layer 36 after patterning amorphous semiconductor layer 18 (FIGS. 2A-2C) is presently preferred because formation of a metal-to-intrinsic-silicon contact near the channel region or active region of the FET could cause injection of minority carriers (holes) into the channel region and increased off current.
It will be readily understood by those skilled in the art that the present invention is not limited to the specific embodiment described and illustrated herein. Different embodiments and adaptations besides those shown herein and described, as well as many variations, modifications, and equivalent arrangements will now be apparent or will be reasonably suggested by the foregoing specification and drawings, without departing from the substance or scope of the invention. While the present invention has been described herein in detail in relation to its preferred embodiments, it is to be understood that this disclosure is only illustrative and exemplary of the present invention and is made merely for purposes of providing a full and enabling disclosure of the invention. Accordingly, it is intended that the invention be limited only by the spirit and scope of the claims appended hereto. | A method for fabricating self-aligned thin-film transistors (TFTs) includes the steps of: exposing a backside substrate surface, opposite to a principal substrate surface, to ultra-violet (UV) light to cause exposure of at least a photoresist layer portion which corresponds substantially to an area outside the shadow of a gate electrode formed on the principal substrate surface; developing the exposed photoresist portion to form a mask; etching a second insulation layer segment, using the mask, to form a remaining insulation layer segment, which is aligned with the gate electrode, and narrower than the gate electrode by a selected overlap distance, on each side thereof; and forming source and drain electrodes on a doped semiconductor layer which each overlap the gate electrode by the selected overlap distance. The overlap distance is a function of the UV exposure time, the photoresist development time and the etch time of the second insulation layer. | 8 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] The present application is a continuation of international application PCT/EP2005/011079, filed 14 Oct. 2005, and which designates the U.S. The disclosure of the referenced application is incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] The invention relates to a device for the steam treatment of a moving fiber strand. A device of this type has been disclosed in the U.S. Pat. No. 4,949,558. For the purpose of steam treatment of a moving fiber strand, the device known from the prior art comprises an elongated steam chamber, which comprises a feed roller pair at a feed end and an exit roller pair at an exit end for sealing the steam chamber. The feed roller pair is connected to the steam chamber in a pressure-tight manner by means of a feed chamber and the exit roller pair is likewise connected to the steam chamber in a pressure-tight manner by means of an exit chamber. The feed roller pair and the exit roller pair each comprise two sealing rollers, which form a nip between them for guiding the fiber strand. One of the sealing rollers is designed to be displaceable so as to adjust the nip in a manner that is adapted to the respective fiber type. During the operation, the sealing rollers are pressed against one another so as to enable the fiber strand, which is guided into the nip, to enter or leave the steam chamber tightly.
[0003] In principle, however, the shortcoming of devices of this type is that the displaceable sealing roller, which is held in a changed position, requires considerable sealing effort in order to prevent the steam from leaking on the circumferential surfaces of the sealing roller. In the device known from the prior art, the sealing rollers are completely integrated in the feed chamber or the exit chamber so as to form very largely dimensioned chambers for the steam treatment. In addition to the high requirement of steam for the steam treatment, it is further hardly possible to carry out a precise conditioning of the fiber strand in the oversized steam chamber. A sealing concept of this type has been disclosed, for example, in U.S. Pat. No. 5,074,130.
[0004] U.S. Pat. No. 5,074,130 describes a device, in which the sealing rollers are integrated inside the adjoining chamber. The circumferential surfaces of the sealing rollers are sealed from the adjoining chamber by means of sealing strips, which are assigned to each of the sealing rollers and which are held on that side of the sealing rollers, which is opposite the nip, against the circumference of the sealing rollers. The integration of the sealing rollers in the adjoining chamber leads to a treatment chamber that is oversized in relation to the fiber strand. Furthermore, the sealing forces acting on the sealing strips are parallel to the contact forces acting in the nip between the sealing rollers. Extreme signs of wear are thus unavoidable on the sealing strips.
[0005] The German Patent Specifications DE 28 29 323 (U.S. Pat. No. 4,184,346) and DE 30 25 978 (U.S. Pat. No. 4,261,586) each disclose a device for sealing a steam chamber, in which device the sealing rollers are disposed outside the adjoining chamber so as to be able to implement appropriately relatively small steam chambers for treating the fiber product. However, these devices known from the prior art comprise two fixed sealing rollers with the result that it is not possible to adjust the nip. The adjoining chambers are sealed from the circumferential surfaces of the sealing rollers by means of plates abutting against the circumference of the sealing rollers. Consequently, a change in the position of any of the sealing rollers would necessarily lead to leakages.
[0006] DE 25 25 833 (U.S. Pat. No. 4,020,657) discloses another device in which two sealing rollers are connected by means of a feed chamber or an exit chamber to a steam chamber. For sealing the exit chamber, two sealing lips are provided, which abut against the circumference of the sealing rollers. The sealing lips are made of a resilient material, wherein an internal pressure, which acts in the interior of the chamber, acts on the sealing lips in such a way that the latter are pressed against the circumference of the roller. Here also, the nip formed between the sealing rollers for guiding a fiber strand is not designed to be alterable. In addition, it must be taken into account that the free ends of the sealing lips are directed towards the circumferential direction of the sealing rollers in order to prevent the sealing rollers from grasping the sealing lips.
[0007] It is therefore an object of the invention to further improve a device for the steam treatment of a moving fiber strand of the type mentioned in the introduction in such a way that it is firstly possible to adjust the nip by means of a displaceably held sealing roller and secondly to implement a relatively small chamber, which is sealed laterally next to the sealing rollers. Another aim of the invention is to provide a device, which is particularly suitable for high steam pressures.
SUMMARY OF THE INVENTION
[0008] The above objectives and others are realized according to the invention by providing, in one embodiment, a device for the steam treatment of a moving fiber strand, comprising an elongated steam chamber, which comprises at least one steam inlet, a feed roller pair, which forms a nip and which is connected to one end of the steam chamber by means of a feed chamber in such a way that the nip constitutes a feed into the steam chamber, and a exit roller pair, which forms a second nip and which is connected to the other end of the steam chamber by means of an exit chamber in such a way that the second nip constitutes an exit from the steam chamber, the feed roller pair and the exit roller pair each being formed by a fixed sealing roller and a displaceable sealing roller, wherein at least one of the feed chamber or the exit chamber comprises a sealing surface lying opposite the roller circumference of the displaceable sealing roller, thus sealing the nip and a displaceable sealing strip, which is located within said sealing surface and is pre-stressed against the circumference of the sealing roller.
[0009] A special advantage of the invention is that a contact seal combined with a nip seal is used for sealing the chamber assigned to the sealing rollers from the roller circumference. For this purpose, the chamber comprises a displaceable sealing strip opposite the roller circumference of the displaceable sealing roller, which sealing strip is pre-stressed against the circumference of the sealing roller. For this purpose, the sealing strip is held within a sealing surface of the chamber, which sealing surface seals the nip opposite the roller circumference of the sealing roller. The contact seal formed between the chamber and the roller circumference is thus embedded within a nip seal and is shielded from the actual chamber. Furthermore, it is possible to guide the sealing strip irrespective of the rotational direction of the sealing rollers. The pre-stress acting on the sealing strip further enables relative movements of the sealing roller towards the chamber without any gap formation. The invention is thus particularly suitable for implementing the smallest treatment chambers irrespective of the roller geometry.
[0010] The refinement of the invention in which the sealing surface is designed on a top plate, which extends parallel to the sealing roller and in which the sealing strip is held in a guide groove of the top plate, which guide groove is connected by means of a pressure channel in the groove bottom to the interior of the chamber, is characterized in that the pre-stress of the sealing strip for its abutment against the circumferential surface of the sealing roller is determined by the internal pressure prevailing in the chamber. It is thus possible to adjust an advantageous leakproofness of the sealing roller, thus enabling a steam treatment at operating pressures exceeding 20 bar.
[0011] In order to ensure at the start of the process or even at lower operating pressures that the sealing strip abuts against the roller circumference of the sealing roller with contact thereto, at least one pressure spring is stressed between the sealing strip and the groove bottom of the guide groove, by means of which pressure spring the sealing strip is held with a minimum contact pressure against the surface of the sealing roller.
[0012] In order to achieve high efficiency of the nip seal in addition to the contact seal, the sealing surface for sealing the nip is designed with a shape, which is adapted firstly to the circumference of the sealing roller and secondly to an operationally permissible change in the position of the sealing roller according to a particularly advantageous refinement of the invention. It is thus possible to achieve pressure decay within the nip seal in any operating position of the displaceable roller. Furthermore, it is advantageously possible to ensure that the gap existing within the contact seal, between the sealing surface and the roller circumference remains substantially constant regardless of the respective operating position of the sealing rollers.
[0013] In order to achieve the most constant possible sealing conditions on the sealing rollers for sealing the feed chamber or the exit chamber, the seals between the chamber and the fixed sealing rollers are designed identically. Particularly, the contact pressure adjusted depending on the chamber pressure between the sealing strip and the circumference of the sealing roller has a wear-resistant effect since the sealing strips are constantly held against the sealing roller with the required contact pressure, which is adapted to the operating conditions in each case.
[0014] The refinement of the invention in which the sealing rollers comprise a steel jacket and in which the sealing strips consist of a metallic alloy, is particularly suitable for enabling a high-temperature treatment of the fiber strand. It is thus possible to set a steam atmosphere of up to 225° in the steam chamber.
[0015] That refinement of the invention has proved to be particularly wear-resistant and temperature-resistant, in which the sealing strips are manufactured from bronze.
[0016] However, it is also possible to use sealing rollers having a rubberized surface or combinations of a steel roller and a rubber roller. When using rubber rollers, the sealing strips are preferably provided with a suitable coating, for example, Teflon.
[0017] In addition to the displaceability of the sealing rollers for adjusting a definite nip, in order to simplify handling when placing a fiber strand, the displaceable sealing roller is held on the pivoting support according to a preferred refinement of the invention, in which the pivoting support can be guided by means of a controllable actuator about a pivot axis disposed on the side of the chamber. It is thus possible to achieve both relatively small movements and also a complete separation of the pairs of sealing rollers.
[0018] In addition to the displaceability of the sealing rollers, in order to be able to generate the necessary build-up of the contact forces between the sealing rollers during operation, the actuator is advantageously formed by means of a piston cylinder unit, using which it is possible to adjust a sealing force between the roller pair during the treatment of a fiber strand.
[0019] For additionally sealing the feed chamber or the exit chamber and the associated sealing rollers, it is suggested that the feed chamber or the exit chamber or alternatively both the chambers be delimited by means of side plates, which extend up to the front sides of the sealing rollers. For sealing the front sides of the roller pair, the side plates each comprise a pressure plate, which can be displaced relative to the sealing rollers. The pressure plates are pressed against the front sides of the sealing rollers with a holding force and are simultaneously set into a motion, preferably a rotary motion. For this purpose, the pressure plates are designed substantially circularly and are guided in the side plates.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] Having thus described the invention in general terms, reference will now be made to the accompanying drawings, which are not necessarily drawn to scale, and wherein:
[0021] FIG. 1 schematically shows a lateral view of a first exemplary embodiment of the inventive device;
[0022] FIG. 2 schematically shows a front view of the exemplary embodiment shown in FIG. 1 ;
[0023] FIG. 3 schematically shows a cross-section of a section in the region of the feed chamber of the exemplary embodiment shown in FIG. 1 ;
[0024] FIG. 4 schematically shows a cross-section of a section in the region of the seal on the circumference of a sealing roller according to the exemplary embodiment shown in FIG. 1 ;
[0025] FIG. 5 schematically shows a section of another exemplary embodiment of the inventive device; and
[0026] FIG. 6 schematically shows a section of a front view of the exemplary embodiment shown in FIG. 5 .
DETAILED DESCRIPTION OF THE INVENTION
[0027] The present invention now will be described more fully hereinafter with reference to the accompanying drawings, in which some, but not all embodiments of the invention are shown. Indeed, the present invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. Like numbers refer to like elements throughout.
[0028] FIGS. 1 and 2 show different views of a first exemplary embodiment of the device according to the invention. FIG. 1 schematically shows a lateral view of the exemplary embodiment while FIG. 2 shows a front view thereof. The following description refers to both the figures unless express reference is made to any one of the figures.
[0029] The exemplary embodiment comprises an elongated steam chamber 1 , which is substantially provided with a cylindrically hollow shape. The steam chamber 1 is connected by means of a steam inlet 2 to a steam source (not illustrated). For guiding a fiber strand through the steam chamber 1 , a feed roller pair 3 is disposed on the feed side of the steam chamber 1 and an exit roller pair 6 is disposed on the exit side. The feed roller pair 3 is connected to the steam chamber 1 in a pressure-tight manner by means of a feed chamber 5 . For this purpose, the feed chamber 5 is coupled to the steam chamber 1 by means of a flange connection 9 . 1 . On the opposing exit side, the exit roller pair 6 is connected to the steam chamber 1 in a pressure-tight manner by means of an exit chamber 8 . The connection between the steam chamber 1 and the exit chamber 8 is created by means of a flange connection 9 . 2 .
[0030] The structure of the feed roller pair 3 with the associated feed chamber 5 is identical to that of the exit roller pair 6 with the associated exit chamber 8 . Therefore, only the structure of the feed roller pair 3 with the associated feed chamber 5 is described in detail in the explanation below.
[0031] The components of the feed roller pair 3 and of the exit roller pair 6 with the associated chambers 5 and 8 have been provided with the same reference numerals for this purpose.
[0032] FIG. 1 schematically shows a cross-sectional view of the feed roller pair 3 and the feed chamber 5 and a lateral view of the exit roller pair 6 with the exit chamber 8 .
[0033] Two sealing rollers 4 . 1 and 4 . 2 , which can be driven, form the feed roller pair 3 . The lower sealing roller 4 . 1 is mounted rotatably in a bearing block 13 and is coupled to a drive (not illustrated).
[0034] The upper sealing roller 4 . 2 is mounted rotatably on a pivot support 11 and is likewise coupled to a drive (not illustrated). The pivot support 11 is L-shaped and is mounted on its side that is turned towards the steam chamber 1 by means of a pivot axis 12 on the bearing block 13 . An actuator designed as a cylinder piston unit 14 engages at the pivot support 11 .
[0035] The sealing rollers 4 . 1 and 4 . 2 are held in such a way in relation to one another that a predetermined nip 10 is formed between the circumference of the sealing rollers 4 . 1 and 4 . 2 . The nip 10 represents a feed cross-section for guiding a fiber strand into the feed chamber 5 .
[0036] On that side of the feed roller pair 3 , which is turned towards the steam chamber 1 , the feed chamber 5 is directly connected to the sealing rollers 4 . 1 and 4 . 2 . The feed chamber 5 is formed by means of a top plate 15 and a bottom plate 16 , each of which is connected tightly to the circumference of the sealing rollers 4 . 1 and 4 . 2 , and two side plates 17 . 1 and 17 . 2 . The formation of the seal between the sealing rollers 4 . 1 and 4 . 2 and the feed chamber 5 is explained in detail below.
[0037] On each of the front sides of the sealing rollers 4 . 1 and 4 . 2 , the side plates 17 . 1 and 17 . 2 are disposed, which are fixedly connected to the top plate 15 and the bottom plate 16 . The side plates 17 . 1 and 17 . 2 extend in such a way over the front sides of the sealing rollers 4 . 1 and 4 . 2 that the feed chamber 5 is sealed from the circumferential surfaces of the sealing rollers 4 . 1 and 4 . 2 and also from the front sides of the sealing rollers 4 . 1 and 4 . 2 .
[0038] One may refer to FIGS. 3 and 4 for the explanation of the seal between the sealing rollers 4 . 1 and 4 . 2 and the feed chamber 5 . FIG. 3 shows a cross-sectional view of the sealing rollers 4 . 1 and 4 . 2 with the adjoining feed chamber 5 and FIG. 4 shows an enlarged view of the seal between the sealing roller 4 . 2 and the top plate 15 . The following description applies to both the figures unless express reference is made to any one of the figures.
[0039] The front side of the top plate 15 , which front side is turned towards the sealing roller 4 . 2 , comprises a sealing surface 20 . 1 , which extends up to the front sides of the sealing roller 4 . 2 . A sealing gap 24 . 1 is formed between the sealing surface 20 . 1 and the circumferential surface of the sealing roller 4 . 2 . A guide groove 21 . 1 is embedded within the sealing surface 20 . 1 in the top plate 15 . The guide groove completely penetrates the top plate 15 up to the front sides thereof, the guide groove 21 being closed laterally by the side plates 17 . 1 and 17 . 2 . A sealing strip 19 . 1 is held in the guide groove 21 . 1 , the sealing strip 19 . 1 and the guide groove 21 . 1 each comprising an extension for forming a stop 26 . The sealing strip 19 . 1 is held in the guide groove 21 . 1 such that it can be displaced transversely to the sealing surface 20 . 1 . A pressure spring 23 . 1 is stressed between the sealing strip 19 . 1 and the groove bottom 27 of the guide groove 21 . 1 so as to press the sealing strip 19 . 1 under pre-stress against the circumferential surface of the sealing roller 4 . 1 . The guide groove 21 . 1 is coupled by means of a pressure channel 22 . 1 to the interior of the feed chamber 5 .
[0040] For a sealing action between the bottom plate 16 and the lower sealing roller 4 . 2 , a sealing surface 20 . 2 is likewise designed on the bottom plate 16 , which sealing surface forms a substantially constant sealing gap 24 . 2 up to the front sides of the sealing roller congruently to the roller surface of the sealing roller 4 . 1 . The guide groove 21 . 2 for guiding a sealing strip 19 . 2 is inserted in the sealing surface 20 . 2 of the bottom plate 16 . The design of the guide groove 21 . 2 and the sealing strip 19 . 2 is identical to that of the guide groove 21 . 1 and the sealing strip 19 . 1 . A pressure spring 23 . 2 is stressed between the sealing strip 19 . 2 and the groove bottom 27 of the guide groove 21 . 2 with the result that the sealing strip 19 . 2 abuts with a minimum contact pressure against the circumference of the sealing roller 4 . 1 . The guide groove 21 . 2 is connected by means of a pressure channel 22 . 2 to the interior of the feed chamber 5 .
[0041] In the operating state, the medium held in the interior of the feed chamber 5 arrives by means of the pressure channels 22 . 1 and 22 . 2 into the guide grooves 21 . 1 and 22 . 2 . The excess pressure prevailing in the interior of the feed chamber 5 acts on the lower sides of the sealing strips 19 . 1 and 19 . 2 so as to press the sealing strips 19 . 1 and 19 . 2 with their sealing ends against the circumferential surfaces of the sealing rollers 4 . 1 and 4 . 2 . A sealing force, which is determined depending on the excess pressure in the steam treatment is adjusted between the sealing strips 19 . 1 and 19 . 2 and the circumferential surfaces of the sealing rollers 4 . 1 and 4 . 2 . The sealing gaps 24 . 1 and 24 . 2 are dimensioned in such a way for supporting the contact seal that there results constant pressure decay. Here, the sealing gap can measure up to 0.1 mm.
[0042] If the displaceable sealing roller 4 . 2 is guided by means of the pivot support 11 into an operating position that increases the nip 10 , the sealing function of the contact seal is retained completely. For this purpose, FIG. 4 shows a situation in which the nip 10 for guiding a fiber strand has been increased. The sealing roller 4 . 2 is guided on a guideway about the pivot axis 12 relative to the top plate 15 . The pivot axis 12 and the contour of the sealing surface 20 . 1 on the top plate 15 are coordinated in such a way to one another that the circumference of the sealing roller 4 . 2 rolls off substantially over the sealing end of the sealing strip 19 . 1 . For forming the relative movement of the sealing roller 4 . 2 , the rounding radius of the sealing surface 20 . 1 on the top plate 15 in the upper region is such that a constant sealing gap 24 . 1 is retained when the position of the sealing roller 4 . 2 changes.
[0043] One may refer to the FIGS. 1 to 3 for the explanation below of the functioning of the device according to the invention. At the start of the process, the displaceable sealing rollers 4 . 1 of the feed roller pair 3 and the exit roller pair 6 are initially pivoted by each of the associated pivot supports 11 out of their operating position into a contact position (not illustrated here). Now a fiber strand is threaded into the steam chamber 1 by means of the feed chamber 5 and guided out by means of the exit chamber 8 . After the fiber strand has been threaded, the displaceable sealing rollers 4 . 2 of the feed roller pair 3 and of the exit roller pair 6 are set back into their operating position and a sealing force acting between the sealing rollers 4 . 1 and 4 . 2 is adjusted by means of the associated cylinder piston units 14 . The sealing rollers 4 . 1 and 4 . 2 of the feed roller pair and of the exit roller pair 6 are driven at constant circumferential speed so as to guide the fiber strand through the steam chamber 1 while maintaining a predetermined stress. A treatment medium, preferably steam, held under excess pressure, is introduced into the steam chamber 1 by means of the steam inlet. Excess pressure of up to 25 bar and temperatures of up to 225° C. can be set in the interior of the steam chamber 1 .
[0044] The feed side of the steam chamber 1 and the exit side of the steam chamber 1 are each sealed from the ambience on one side by means of nips 10 between the sealing rollers 4 . 1 and 4 . 2 and by the front-sided seal between the side plates 17 . 1 and 17 . 2 and the circumferential seals between the sealing rollers 4 . 1 and 4 . 2 and the associated chamber plates. Particularly the sealing strips 19 . 1 and 19 . 2 held in the top plates 15 and the bottom plates 16 are pressed against the respective circumferential surfaces of the sealing rollers 4 . 1 and 4 . 2 under the effect of the excess pressure within the steam chamber. For this purpose, the sealing strips 19 . 1 and 19 . 2 are formed out of a metallic alloy, preferably bronze, and they abut directly against the steel jacket of the sealing rollers 4 . 1 and 4 . 2 . This combination of materials has proved to be particularly wear-resistant, thus easily enabling temperature loads of more than 225° C.
[0045] FIGS. 5 and 6 show another exemplary embodiment of a device according to the invention, in which particularly a wear-resistant front-sided seal between the sealing rollers 4 . 1 and 4 . 2 and the associated chamber 5 is formed. In other respects, the exemplary embodiment shown in FIGS. 5 and 6 is identical to the one previously described. Hence only the differences have been explained here. As shown in FIG. 5 and 6 , two pressure plates 18 . 1 and 18 . 2 are each held in the side plates 17 . 1 and 17 . 2 on the front sides of the sealing rollers 4 . 1 and 4 . 2 .
[0046] The pressure plates 18 . 1 and 18 . 2 are each coupled to a spindle 25 . 1 and 25 . 2 . The spindles 25 . 1 and 25 . 2 firstly help transfer a compressive force onto the pressure plates 18 . 1 and 18 . 2 so as to press the pressure plates 18 . 1 and 18 . 2 directly on the front sides of the sealing rollers 4 . 1 and 4 . 2 . Secondly, the spindles 25 . 1 and 25 . 2 help introduce a rotary motion for forming an additional relative movement of the pressure plate 18 . 1 and 18 . 2 , thereby causing the pressure plates 18 . 1 and 18 . 2 to perform a rotary motion. For this purpose, the pressure plates 18 . 1 and 18 . 2 are preferably designed circularly.
[0047] As shown in FIG. 5 , the pressure plates 18 . 1 and 18 . 2 extend up to the sealing surface of the top plate 15 and of the bottom plate 16 so as to ensure that the feed chamber and the exit chamber are completely sealed from the ambience.
[0048] Due to the permissibility of high temperatures and high excess pressures, the device according to the invention is particularly suitable for a steam treatment in order to treat spinning cables in a staple fiber process. The necessary nip between the sealing rollers is adjusted easily depending on the cable thickness. Furthermore, it is possible to insert the spinning cable in a user-friendly manner since the displaceable sealing rollers can be folded away completely. The use of hard sealing rollers provided with a steel jacket additionally leads to a good guidability of the spinning cable without drawing off individual fibers from the fiber assembly due to their adhesion to the surface of the sealing rollers.
[0049] Many modifications and other embodiments of the invention set forth herein will come to mind to one skilled in the art to which this invention pertains having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. Therefore, it is to be understood that the invention is not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the appended claims. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation. | The invention relates to a device for the steam treatment of a moving fiber strand, comprising an elongated steam chamber. To seal the steam chamber, a pair of feed rollers is connected to and seals a feed chamber on a feed side in such a way that the nip constitutes the feed into the steam chamber. The opposing exit side is equipped with a pair of exit rollers, which forms a second nip and which is connected to and seals the other end of the steam chamber by means of an exit chamber, in such a way that the second nip constitutes the exit from the steam chamber. The feed roller pair and the exit roller pair are respectively formed by a fixed sealing roller and a displaceable sealing roller. The aim of the invention is to achieve a seal between the sealing roller and the associated sealing chamber, irrespective of the operating position of the displaceable roller. To achieve this, the feed chamber and/or exit chamber comprise(s) a sealing surface lying opposite the roller circumference of the displaceable sealing roller, thus sealing the nip, and a displaceable sealing strip, which is located in said sealing surface and is pre-stressed against the circumference of the sealing roller. | 3 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application claims benefit and priority under 35 U.S.C. §119(e) from U.S. Provisional Application 61/138,803 filed Dec. 18, 2008, entitled PRE-INSULATED STRUCTURAL BUILDING PANELS and also from U.S. Provisional Application 61/227,586 filed Jul. 22, 2009, entitled INSULATED STRUCTURAL WALL SYSTEM, the disclosures of which are incorporated by reference herein in their entirety.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention is directed generally to a method and apparatus for pre-insulted structural panels. More particularly, the invention is directed to pre-insulated structural building panels configured with vertical support members, acoustical aspects and wiring friendly features, among other aspects.
2. Related Art
Building construction often employs pre-manufactured components such as building panels that may be assembled in the field to create walls and perimeters of buildings of all sorts. Often the components may include expandable polystyrene foam (EPS), or similar material. The EPS material may provide thermal insulating properties to a degree related to the thickness of the EPS panel.
Moreover, the various types of building components currently available typically have limited features that assist in the installation of the components or finishing off of the building wall surfaces and/or related building functions. Moreover, the currently available products provide limited acoustical dampening aspects.
Furthermore, current building components are often of relatively small size and may require multiple components to create a vertical dimension in the height of a wall, which may require extra installation time and costs.
Accordingly, there is a need for a method and apparatus that provides a pre-insulated building panel with improved features to reduce installation costs and time, while providing improved structural integrity to the resulting wall.
SUMMARY OF THE INVENTION
The invention meets the foregoing need and provides a method and apparatus for constructing a pre-insulated structural panel that includes vertical c-channels or profiles spaced apart for imparting structural integrity to the panel and the c-channels embedded in EPS foam to create the panel. One side of the panel may be configured with a tongue shaped edge that runs along one side of the panel. On the other side of the panel a groove shaped edge may be formed to mate with the tongue shaped edge of another panel when two panels are arranged side-by-side to form a wall section. A fastening plate may be employed to fasten two panels together when placed side-by-side.
In one aspect, a horizontal chase may be provided from one side of the panel to the other side to permit running of wiring through the panel and in a resulting wall. The chase of one panel aligns with a respective chase in another panel when installed. Moreover, a vertical chase may be provided between mated panels proximate the tongue and groove mated surfaces for running wiring or for providing an additional a structural member for added structural strength.
In another aspect, an apparatus for a pre-insulated building component is provided that includes a plurality of vertical support channels embedded in an insulating material to produce a first panel and a second panel, a groove end configured in one side of each panel, and a tongue end configured in another side of each panel, wherein the tongue end of the first panel mates with the groove end of the second panel to form a wall section.
In another aspect, an apparatus for a pre-insulated building component is provided that includes means for constructing an expandable polystyrene (EPS) wall section, wherein the means for constructing includes a means for attaching finishing materials at spaced apart intervals and the means for attaching provides lateral force resistance to the EPS wall section, means for accepting electrical wiring laterally through the interior of the EPS wall section and means for securing the wall section at a bottom end and at a top end, wherein the means for securing at the bottom end and the top end are connected by a means for connecting that traverses an entire height of the wall section.
In another aspect, a method for providing a pre-insulated building component is provided that includes providing a plurality of vertical support channels embedded in an insulating material to produce a first panel and a second panel, providing a groove end configured in one side of each panel, and providing a tongue end configured in another side of each panel, wherein the tongue end of the first panel mates with the groove end of the second panel to form a wall section.
Additional features, advantages, and embodiments of the invention may be set forth or apparent from consideration of the following detailed description, drawings, and claims. Moreover, it is to be understood that both the foregoing summary of the invention and the following detailed description are exemplary and intended to provide further explanation without limiting the scope of the invention as claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are included to provide a further understanding of the invention, are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the detailed description serve to explain the principles of the invention. No attempt is made to show structural details of the invention in more detail than may be necessary for a fundamental understanding of the invention and the various ways in which it may be practiced. In the drawings:
FIG. 1A illustrates in perspective view a pre-insulated structural panel configured according to principles of the invention;
FIG. 1B illustrates a frontal view of the embodiment of FIG. 1A ;
FIG. 1C illustrates a first side-view of the embodiment of FIG. 1A , configured according to principles of the invention;
FIG. 1D illustrates a second side-view of the embodiment of FIG. 1A ;
FIG. 1E illustrates an end-view of the embodiment of FIG. 1A ;
FIG. 2A is a front-view of an embodiment of a plurality of pre-insulated structural panels of FIG. 1A configured to form a wall, according to principles of the invention;
FIG. 2B is a top view of the embodiment of FIG. 2A ;
FIG. 2C is a side view of the embodiment of FIG. 2A ;
FIG. 3A is an illustration showing an embodiment of a wall section comprising a plurality of pre-insulated structural building panels constructed according to principles of the invention;
FIG. 3B is a top view of a section of a base plate and/or a header plate with attaching mechanisms, constructed according to principles of the invention; and
FIG. 3C is an end-on view of the section of FIG. 3B .
DETAILED DESCRIPTION OF THE INVENTION
The embodiments of the invention and the various features and advantageous details thereof are explained more fully with reference to the non-limiting embodiments and examples that are described and/or illustrated in the accompanying drawings and detailed in the following description. It should be noted that the features illustrated in the drawings are not necessarily drawn to scale, and features of one embodiment may be employed with other embodiments as the skilled artisan would recognize, even if not explicitly stated herein. Descriptions of well-known components and processing techniques may be omitted so as to not unnecessarily obscure the embodiments of 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 of skill in the art to practice the embodiments of the invention. Accordingly, the examples and embodiments herein should not be construed as limiting the scope of the invention, which is defined solely by the appended claims and applicable law. Moreover, it is noted that like reference numerals represent similar parts throughout the several views of the drawings.
FIG. 1A is a perspective view of a pre-insulated structural building panel, constructed according to principles of the invention, generally denoted by reference numeral 100 . The pre-insulated structural building panel 100 includes a plurality of c-channels 105 that runs the extent of the length (L) of the panel 100 . The panel 100 is typically installed with the length (L) oriented vertically, as shown perhaps more clearly in relation to FIG. 2A . The plurality of c-channels 105 may comprise steel channels having lips 135 formed in the sides of the c-channels 105 to embed the c-channels 105 into the expandable polystyrene (EPS) 140 during fabrication of the panels 100 . The EPS provides substantial structural support in combination with the c-channels 105 . In some embodiments, the c-channels 105 may comprise any metal or plastic type material. During fabrication or molding, the EPS may be injected or molded between opposing c-channels 105 located on both sides of the panel 100 , and also continuously between the c-channels 105 , whereby the EPS may be substantially continuous along the entire length and height of the panel 100 including between the opposing c-channels. The EPS is fully bonded to the steel (i.e., c-channels 105 ) as this is part of the manufacturing process. A thermosetting adhesive is used to coat the steel prior to molding the panels 100 .
The panel 100 may be constructed to nearly any required dimension in thickness (t), width (w) and length (L). Common dimensions include about 4, about 8, about 10 or about 12 foot length, 4-6 inch thickness, and 4-6 feet width. But, nearly any dimensionality may be constructed, according to the application need or customer requirements.
The c-channels 105 may be placed at any spacing intervals, such as 4 foot centers, for example, and any spacing to imitate common (or traditional) spacing for “studs.” Two-foot center-to-center spacing is also quite common, as is 16 inch spacing. Nearly any spacing, including irregular spacing, may be provided. The c-channels 105 may comprise structural members to facilitate attaching finishing materials such as dry wall, panels, wood siding, vinyl siding, fiber-cement such as Hardiplank®, and the like. The surfaces of the panel 100 may be covered with stucco, gunite, resins, paints, or similar materials, as needed. The c-channels 105 laterally support the EPS and provide substantial weight bearing capability to support the building load generally and to provide attachment capability for siding materials.
A tongue side 110 and a groove side 120 may be formed along the length (L) of the panel 100 , and configured to form a tongue-in-groove assembly when two or more panels 100 are arranged side-by-side, to form a wall section 200 such as shown in relation to FIG. 2A , for example. The tongue side 110 is configured to mate with the groove side 120 of another panel. When so mated, a vertical chase 150 may be formed between the respective tongue and the groove edges as an interior chase along the length (L) of the mated panels 100 . The vertical chase 150 may be about one inch in width (i.e., between the lateral tongue edge and the lateral groove edge) to permit installation of wiring between the mated panels 100 . Alternatively, a structural strengthening member or stabilizer, such as a metal bar, perhaps having a length of about (L), may be inserted into the vertical chase 150 to provide added strength to the resulting wall, such as for added load bearing capacity, for example. An example of a structural strengthening member is described more fully in relation to FIG. 3 , below.
A horizontal chase 130 (as viewed when installed) may be formed (but not always necessary) during the molding fabrication process and configured to extend from the tongue side 110 to the groove side 120 , through the interior of the panel 100 . The horizontal chase 130 may be about 1½ inches in diameter, but any diameter suitable for a particular application may be constructed. This horizontal chase 130 may provide for accepting wiring runs such as electrical wiring (or perhaps even plumbing) so it may be inserted into or through the panel 100 at the building site to provide power and/or communications, for example. A chase 130 of one panel 100 may align with the chase of an adjacent panel 100 , so that wiring may run substantially unimpeded through multiple panels 100 . The horizontal chase 130 may be configured with a tapered opening 115 , as a lead-in for aiding in guiding inserted wires into the horizontal chase 130 , also assisting running of the wire from one panel 100 to an adjacent panel 100 .
The EPS portions 140 of the panels 100 may be molded to hold c-channels 105 in place relative to one another using molding techniques of various types. The EPS portions 140 provide substantial structural strength in combination with the c-channels 105 . The EPS portions 140 may be constructed with acoustical protrusions 125 on the outer surface of the EPS. The acoustical protrusions 125 may be about ⅛ inch in height, but may vary some. The acoustical protrusions 125 may provide a spacing factor or gap between the EPS outer surface and any applied siding or covering such as dry wall, for example. The extra spacing provided by the acoustical protrusions 125 significantly reduces acoustical noise from penetrating through a finished wall. The acoustical protrusions 125 may be spaced at regular (or perhaps irregular) intervals such as 2 inches, or so, from one another, but can vary, along an extent of a panel so that a sound barrier is also created in a vertical sense so that sound may be prevented, or at least reduced, in propagation ability in a vertical sense along the EPS surface. That is, the series of acoustical protrusions 125 may also inhibit sound propagation laterally along the EPS outer surface, in addition to creating a dampening effect by creation of the space factor or gap. Such a space factor or gap may be created between the EPS foam and any applied finishing materials such as dry wall sheet, siding, or finishing panels, for example, so that the protrusions 125 formed along the width of the EPS portions 140 thereby inhibit sound travel along the surface of the panel, especially, but not limited to, in a vertical sense.
FIG. 2A is a side view of a plurality of pre-insulated structural building panels 100 , configured to form a wall section 200 . The wall section 200 may be arranged so that a tongue side 110 is mated with a groove side 120 of another panel 100 . A fastening plate 160 may be used to fasten the plurality of panels 100 together.
FIG. 3A is an illustration of an embodiment of a wall section comprising a plurality of pre-insulated structural building panels constructed according to principles of the invention, the wall section generally denoted by reference numeral 300 . The pre-insulated structural building panels 305 , 310 comprising the wall section 300 are shown in two different lengths, for example 4 foot panels and 8 foot panels, arranged in a checkerboard fashion, with a longer size panel 310 layered on top of a shorter panel 305 (the pair shown in the left-hand side of FIG. 3A ), and then the pair coupled laterally by tongue-in-groove mating, as described previously, with a second pair of panels (the pair shown in the right-hand side in FIG. 3A ). The second pair of panels includes a shorter panel 305 layered on top of a longer panel 310 . The tongue-in-groove arrangement may be configured to form a vertical chase 150 for receiving a structural strengthening member 330 , such as a metal bar, that may extend the entire height of the layered panels (in this example, about 12 feet of extent). In this way, extra strengthening and/or extra stabilizing characteristics may be provided to enhance structural integrity of the side-by-side sets of panels. The checkerboard pattern itself also provides additional resistance to lateral movement of the panels 100 . The panels 305 , 310 may comprise any embodiments of panel 100 . Panels 305 and 310 are shown in FIG. 3A without any c-channels 105 (and several other features of FIGS. 1A-1C ) to permit enhancement of particular features being described in relation to FIG. 3A , but the c-channels 105 (and the other features of FIGS. 1A-1C ) may be interpreted as being included in the embodiment of FIG. 3A .
Further, an optional based plate 320 , mountable to a floor or other surface, may have lips 322 configured to receive the lower side of the respective lower panels 305 , 310 . The base plate 320 may serve at least in part to stabilize the wall section 300 to a floor, or similar surface, and may be of any length to match any number of side-by-side panels being installed for an application. The base plate 320 may be configured with one or more attaching mechanisms 335 (see the top view of the base plate/header plate as shown in FIG. 3B ), which may be holes, to secure the structural strengthening member 330 to the base plate 320 . Moreover, an optional header plate 325 may be employed at the top of the upper panels 305 , 310 to provide added structural integrity at the top of the wall section 300 . The header plate 325 may be configured similarly to the base plate 320 , as shown in relation to the end-on view of FIG. 3C . The header 325 may also have lips 322 and may also have attaching mechanism 335 to receive the structural strengthening member 330 . The header 325 may be secured to an appropriate structure for securing the wall section 300 at the top and may be of any length to match any number of side-by-side panels being installed for an application. The structural strengthening member 330 may be cut to length, as needed, which may be more than 12 feet in this example.
While the invention has been described in terms of exemplary embodiments, those skilled in the art will recognize that the invention can be practiced with modifications in the spirit and scope of the appended claims. These examples given above are merely illustrative and are not meant to be an exhaustive list of all possible designs, embodiments, applications or modifications of the invention. | An apparatus and method for constructing pre-insulated structural panels is disclosed that has a tongue and groove assembly arrangement. Each panel may include one or more c-channels or profiles embedded in expandable polystyrene (EPS) foam to provide structural integrity to the panels, and resulting wall. The panels may be covered with siding, stucco, or similar materials. A chase may be formed horizontally in the panels to provide a wiring conduit through the panel. The panel may also provide when assembled, a vertical chase formed between the mated panels along the length of the panel for wiring. Acoustical properties may be formed in the surface of the EPS portions to provided added acoustical damping measures. | 4 |
TECHNICAL FIELD
The present invention relates to a queue control system. Especially the present invention relates to a queue control system for guiding persons waiting for service by a plurality of service points, such as check-in desks at an airport.
BACKGROUND OF THE INVENTION
Queue control systems may be used in many places for guiding persons waiting for service by a plurality of service points, such as check-in desks at an airport, tellers at banks, etc in order to guide persons' queuing.
Queue control systems may thus used for example in commercial banks servicing a large number of customers. The customers may nowadays for example form a single queue which is serviced by a plurality of tellers, and as each customer reaches the beginning of the queue the customer proceeds to the first available teller. In such a system, the queue length will increase with an increase in the rate of customers joining the queue or with a decrease in the number of tellers servicing the queue, and will decrease with a decrease in the number of customers joining the queue or with an increase in the number of tellers servicing the queue. If the queue becomes too long, this increases the waiting time of the customers and breeds dissatisfaction; but if the queue disappears altogether, this results in one or more tellers being idle and thereby a wastage of labor. Such queues may be controlled by visual observation and personal judgement. However, such a system is very inefficient since it is not only imprecise, resulting in lines becoming too long or completely eliminated, but is also time-consuming since it requires continuous observation by management personnel.
U.S. Pat. No. 5,245,163 discloses a queue monitoring and control system for monitoring and controlling a queue of persons waiting for service by a plurality of clerks, comprising: a card dispenser for dispensing sequentially-numbered cards to persons as each joins the end of the queue; a plurality of card readers, one for each clerk, for reading the card number when received by the clerk from each person as each reaches a clerk at the beginning of the queue; a real time clock for indicating the queue joining time for each card dispensed by the dispenser to a person when joining the end of the queue, and the clerk reaching time for each card read by the card readers as each person reaches a clerk at the beginning of the queue; and a data processor including: means for inputting predetermined fixed data relating to permissible queue parameters; means for inputting the card numbers and queue joining times from the card dispenser and the real time clock, and the card numbers and clerk reaching times from the card readers and the real time clock; and programmed means for controlling the data processor to indicate any changes in the number of clerks required in order to comply with the permissible queue parameters of the inputted fixed data.
Also this kind of prior art queue control systems have certain problems: they are complex and ineffective especially as they require a complex control apparatus with card dispensers and further a plurality of card readers, one for each clerk, for reading the card number when received by the clerk from each person etc.
SUMMARY OF THE INVENTION
The object of the present invention is to eliminate the above-mentioned drawbacks of the prior art queue control systems.
The present invention thus provides a new queue control system for guiding persons waiting for service by a plurality of service points.
The present invention is based on the idea to utilize longitudinal light stripes or bands that arranged in front of the service points to control queuing of the persons and guiding them to choose a right queue from the plurality of queues.
In order to implement this the system is provided with light stripes provided with a plurality of point-like light sources, such as LEDs (Light Emitting Diode) that can be operated in various lighting schemes in order to guide the persons in the queue, and also persons entering or leaving the queue.
The stripe can be located either on or in the floor, on the ceiling or wall mounted or in existing queuing post and tape type systems where the tape was replaced by the stripe.
In a preferred embodiment the light stripe is a LED stripe disclosed in WO 98/23896 which can be controlled in various ways, e.g. with a light moving along the queue or on/off, and which may be provided with LEDs with different colours, typically red and green in this kind of embodiment.
According to a further embodiment of the present invention each queue may be provided with a light stripe arrangement that consists of a longitudinal light stripe, typically the length of which is 5 to 10 m and also a much shorter cross light stripe, so called stop line, arranged at the beginning of the longitudinal stripe perpendicular to it in order to indicate whether that queue can be entered or not.
Characteristic features of the system according to the present invention are in detail presented in the enclosed claims.
The system of the present invention is very reliable, especially when LED stripes provided with a plurality of LEDs are used, effective and simple.
BRIEF DESCRIPTION OF THE DRAWINGS
In the following, the invention will be described in more detail with reference to the appended drawings, in which:
FIG. 1 presents a simplified view of one implementation of the present invention;
FIG. 2 presents a view of FIG. 1 added with a block diagram of the queue control system; and
FIG. 3 presents a LED stripe that may be used in the present invention.
FIG. 4 presents a simplified view of an example implementation of a security control point according to the present invention.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 presents an implementation of the present invention utilizing a light or LED ‘stripe’, i.e. a longitudinal conducting element provided with LEDs, as defined e.g. in WO 98/23896 and further shown in FIG. 3 , to control queuing of people.
In the embodiment of FIG. 1 there are three service points Desk 1 to Desk 3 . In front of each desk there is a longitudinal LED stripe 101 to 103 that is typically 5 to 10 m long arranged as a stripe line in the direction of each queue.
The stripes 101 to 103 can be located either on or in the floor, on the ceiling or wall mounted or in existing queuing post and tape type systems where the tape was replaced by the stripe.
The service point may be a service desk, security control point, passport control point or other service point for services for different kind of applications. The applications may include:
Queuing of people awaiting service at service desks
Passport control queue control.
Security check areas
Check out tills at supermarkets and other retail establishments
Doctors waiting areas
Pharmacies
Banks
Car park payment booths
Toll booths
The system employs stripes consisting of red and/or green LEDs, which are remotely or automatically controlled with a control computer 104 connected to each desk and stripe. Other colours of LED are possible.
The stripe is based on printed circuit board techniques, according to which it is possible to achieve a conducting stripe, that operates in an on/off mode e.g. with alternatively varying colours, and when the stripe includes several longitudinal conductive films it may operated so that it provides a dynamical “moving” light effect which means that the stripes may include dynamic sequencing of the LEDs, that moves along the queuing direction, i.e. toward the desk. Also this moving effect can be implemented with different colours.
By setting up e.g. a floor mounted pattern, such as shown in FIG. 1 the system will enable controlling of people in and entering queues.
The sequences are set up to guide people, for example in FIG. 1 green cross bar 105 would mean you can enter the queue and red cross bars 106 , 107 would mean you cannot enter the queue. Red queue line 102 would mean no-one is allowed in the line and green queue lines 101 , 103 would mean that people can queue there.
The green queue stripes could be flashing in sequence to direct you to move forward and lit continuously if no movement is needed.
Further light or LED stripes could be added if needed, such as a cross bar in front of the desk to allow people to move forward to the desk or not, or multiple cross bars which would control individual queuers.
As an example the following operation might be programmed into the system:
If the queue is open, and people can join the queue then the green stripe would be on and static and the green stripe bar would be on and static. If the person at the desk finishes the interaction and leaves, the green stripe could briefly start dynamic sequencing indicating that members in the queue can move forwards. If the desk is going to close, the cross bar would be changed to red (therefore not allowing people to enter the queue) and the stripe would remain green until the queue had been exhausted and then would turn red. If the desk was opening, the stripe and cross bar could briefly flash green and then go solid green.
Additionally further stripe(s) could be added in dynamic set up to guide you to the correct queue. So where a number of queues were in place, anyone entering the area would be guided to the shortest or empty queuing place by moving sequences of LEDs within the stripe.
By this method the system can enable direction of people to the required queues, and would enable efficient management of people entering the queues and already in the queues.
The queue control system can be controlled either by a queue specific controlling device, such as a program stored on an EPROM, which would control just the components related to a single queue or each component in the whole system could be centrally controlled by a controlling device such as an EPROM or computer based software program. By this manner the state of the stripes and/or other devices would be controlled so that the system performs as required to guide people efficiently.
Connection between the stripes and the controller could be hard wired or by wireless technology.
Additionally the a further indication for queue availability could be attached to the system, either as a high level light which is on when the queue is open or off when queue is closed or closing.
Additionally a display or number of displays could be incorporated into the system which would give text, symbol or audible signs informing people what to do, open or closed or closing status of the queue etc. This display could also be used for advertising or public notices if so required.
In addition, the system could work completely automatically when attached to sensors or sensing equipment which can identify the number of people in a queue. Examples of these types of queue sensors are e.g. a sensor product for electric field sensing, as described e.g. in US2008238433A. The sensor includes a substrate, electrically conductive areas on the surface of the substrate, an output, and at least one conductor between the at least one electrically conductive area and the output. This sensor product can be arranged as a stripe 108 to 110 along each queue and can be used for identifying the presence or movement of persons in the queue. The sensor product can be hidden as a sensor mat into/onto/under/behind floors, walls or roofs. It is also possible to use cameras where the video is processed to show how many people are in a queue, or movement detectors, or trolley or basket mounted tags which are detected by sensors in the queue locations or proximity detectors, or RFID detectors. Sensors could also be directly integrated within the stripe arrangement.
The system could be operated by push buttons 111 to 113 located at the desks or linked to a number assignment system and used by the clerks or other persons working at the desks.
FIG. 3 shows a led stripe according to WO 98/23896 a led stripe, i.e. conducting element consists at least of an elongated and essentially flat electricity conductive conductor part 1 ; 1 ′, such as a band or a stripe in which several electric components 2 ; 2 ′, such as leds, resistors and/or the like bringing out the lighting operation according to the use of the conducting element, are being attached to one after another in the longitudinal direction, and of a casing part 3 . The conducting element is being manufactured by arranging the conductor part and the components existing therewith 1 ; 1 ′, 2 ; 2 ′ when viewed in a cross section totally surrounded by a casing material 3 ′ forming the said casing part 3 , by exploiting a continuous manufacturing process, such as extrusion or like. FIG. 3 illustrates casing part 3 having width W, thickness t, and thickness v under the conductor part 1 . The electric components 2 ′ of a conducting element, that enables preferably dynamic use as well, are being attached preferably by means of surface mounting technics to an electric conductor layer 1 ′ b , such as to a copper coating or like of a basic material 1 ′ a , that is made of plastics, such as polyamide, polyester, polyethylene napthalate or like, of the conductor part 1 ′, that is based on printed circuit board techniques, whereby the electric conductor layer 1 ′ b continues essentially uninterruptedly over the whole length of the conducting element, whereafter the entirety being brought out is being surrounded by a casing material 3 ′, that is based on plastics such as pvc, polyurethane, olefin and/or like. The whole structure is fully water-proof.
It is obvious to the person skilled in the art that different embodiments of the invention are not limited to the example described above, but that they may be varied within the scope of the enclosed claims. A longer transversal cross bar 114 having a length that corresponds to the width of all the desks may be arranger in front of all the stripes in order to guide queuing customers especially when there are many, e.g. twenty, desks.
In FIG. 4 a simplified view of an example implementation of a security control point according to the present invention is presented. The security control point may comprise different control points like baggage detector means 402 like x-ray machine for checking baggage, a waiting point for detector means 404 and detector means 408 . The detector means can be for example a metal detector. The waiting point 404 can use green light signal to indicate the person that he can proceed to the detector means 408 . If detector means is currently in use, a red light can indicate that a person has to wait at the waiting point 404 . After the person has walked through the detector means 408 , lighting means 410 , 414 or 412 can be used to guide the person to a correct point. If for example some metal items are detected, the lighting means 412 may guide the person to a security control person who will conduct a more thorough search for example at Desk 2 ′. If the detector means 408 detect no items, e.g. metal items, the person may be guided with lighting means 410 , 414 to collect his baggage from baggage detector means 402 at Desk 1 ′ or Desk 3 ′. In the example embodiment of the invention the color of the lighting means 410 , 414 is green and color of the lighting means 412 is red. The personnel operating the system can have remote controllers for controlling the status of the system, e.g. for controlling colors of the different indication lights.
Further embodiments of the invention may include:
The queue control system could also be extended to show people out of the area, once they have finished their interaction The queue control system could also be connected to automatic doors for allowing people to exit the area after their interaction has been completed The lighting stripe which is used to guide people to the correct queue could also be multi-colour, which would allow for one person being guided to one queue and another person being guided to another queue simply, and even at the same time. For example, when queuing for a security check an operator can control the stripe to show blue light sequence, and then inform the person to follow that the blue sequence up to the correct queue. A further person might be requested to follow the yellow sequence. The queue control system could also be connected to a public address system to generate audible messages to reinforce the guidance information. The queue control system could also be connected to a theft system, so that if the theft system detects a tagged product which sets off an alarm, then this would cause a red stripe to indicate that the person should stop and wait for assistance. The queue control system can further be fully monitored to indicate if there is a fault, or if light levels are reduced to certain performance levels The queue control system could also be linked to an assistance button, and staff could be guided to the position where assistance is needed.
Although exemplary embodiments of the present invention have been described with reference to the attached drawings, the present invention is not limited to these embodiments, and it should be appreciated to those skilled in the art that a variety of modifications and changes can be made without departing from the spirit and scope of the present invention. | A queue control system for guiding persons waiting for service by a plurality of service desks, such as check-in desks at an airport, the system comprising computer control means for controlling the system, wherein system further comprises: stripe-like or band-like lighting means arranged for each desk (Desk 1 -Desk 3 ) provided with point-like light sources, like LEDs, coupled to a circuit board, the circuit board being adapted to provide variable lighting operations, wherein each lighting means have at least a stripe-like or band-like part ( 101 - 103 ) arranged in the direction of the queue; and wherein the control computer means are adapted to variably control the lighting of the stripe-like or band-like lighting means in order to guide the persons in the queues and/or entering and/or leaving the queues. | 6 |
FIELD OF INVENTION
This invention relates to the determination of the concentration of a multi-component solid/liquid or liquid/liquid mixture. It can be applied to any situation where the density of such a mixture is known or can be determined. This invention provides a means for improving the control of a continuous process which handles such a mixture and is dependent on the mixture's concentration, and can thus assist manufacturers in effectively monitoring and operating their processes. Data generated by this invention can be used to: control a known process fluid to a targeted concentration, for instance in a paper coating process; verify on-line the accuracy of batchwise or continuous ratio blends in the manufacture of such products as food products (ketchup, mayonnaise, syrup), personal care products (skin cream, shampoo), pharmaceutical products, paints, petroleum blends, and the like; and eliminate the excessive empirical work necessary with density monitoring process control systems.
BACKGROUND OF THE INVENTION
The solute content of a solid/liquid or liquid/liquid mixture—commonly expressed as the mixture's concentration—can be determined from the mixture's true density utilizing a relationship that exists between the mixture's concentration and density. This relationship consists of a linear correlation between a mixture's concentration and density, which is unique to each mixture. Stated generally, a unique, linear relationship exists for any solute/solvent mixture (solution or slurry).
Defined hereinbelow is an improvement to the two inaccurate, traditional approaches relating concentration to density. The first, the Non-linear Model, assumes that the solute is completely insoluble in the solvent. The second, the Linear Model, is based on a soluble solute. The present improved relationship is referred to as the CONCENTRATION-DENSITY MODEL. This model allows for a theoretical determination of the concentration-density relationship for a multi-component solid/liquid or liquid/liquid mixture. Included in the Concentration-Density Model is a new concept referred to as ADDITIVE VOLUME COEFFICIENT (AVC). This concept compensates the Non-linear Model for the fact that the net volume of a mixture does not always equal the sum of the volumes of each component.
As described in detail herein, this improved Concentration-Density Model provides fluid-handling manufacturers with a method for accurately determining a mixture's concentration on-line with the aid of current density measurement instrumentation. The Concentration-Density Model of the present invention allows for accurate concentration determination in manufacturing scenarios where such measures were previously impractical. These concentration measurements can then be used to control the manufacturing process.
It is common for a solid/liquid mixture's concentration to be determined in a laboratory by measuring the weight of a sample both before and after evaporating the liquid phase of the mixture. This approach can be very accurate, but must occur off-line which results in a significant time delay between the time of sampling and the time of measurement. This time delay decreases the number of manufacturing applications where this measurement is useful.
Other methods, either off-line or on-line, determine concentration indirectly. A property of a solid/liquid or liquid/liquid mixture (e.g., density, gamma radiation absorption, and so on) is empirically correlated to a mixture's concentration. The mixture's concentration can then be calculated from a measurement of that property (on-line or off-line).
All of these methods, however, face certain challenges. For the sake of accuracy, each mixture to be measured requires the empirical determination of the relationship between the mixture's concentration and density. When many mixtures are involved, this can result in a great deal of upfront effort. To minimize this upfront effort, one of two models relating a mixture's concentration to its density is commonly used.
NON-LINEAR MODEL (Insoluble, Two-component System):
Modeling the case of a mixture (M) where the solute (S) is completely insoluble in the solvent (L), the volumes (V) are additive:
V M =V S +V L Eq.1
Therefore: m M ρ M = m M · x S ρ S + m M · ( 1 - x S ) ρ L Eq. 2-1
where: m=mass, and, ρ= density;
or, 1 ρ M = x S ρ S + 1 - x S ρ L Eq. 2-2
Solving Eq. 2-2 for the mixture's solute content, xs: x S = ρ S ( ρ M - ρ L ) ρ M ( ρ S - ρ L ) Eq. 3
Eq.3 can be rewritten as: x S = ρ S ( ρ S - ρ L ) - ρ S · ρ L ( ρ S - ρ L ) ( 1 ρ M ) Eq. 4
Therefore, on a plot comparing the mixture's concentration to the inverse of it's density: Slope = ρ S · ρ L ( ρ S - ρ L ) ; y - Intercept = ρ S ( ρ S - ρ L )
LINEAR MODEL (Soluble, Two-component System):
Modeling the case of a mixture (M) where the solute is considered soluble in the solvent, it is assumed that the density of the mixture varies linearly from the density of the pure solvent (L) to the density of the pure solute (S), based on the mass ratio of the two components.
This model is expressed as: x S = ρ M - ρ L ρ S - ρ L Eq. 5-1
which can be re-written as: x S = - ρ S ρ S - ρ L + ρ M ρ S - ρ L Eq. 5-2
Therefore, on a plot comparing the mixture's solids content to the it's density: Slope = 1 ρ S - ρ L ; y - Intercept = - ρ L ρ S - ρ L
In both of the above, the formula components are defined as follows:
V M =Total System Volume (Volume of Mixture)
V S =Volume of the Solute
V L =Volume of the Solvent
m M =Total System Mass (Mass of Mixture)
x S =Mass Fraction of the Solute
x L =Mass Fraction of the Solvent
ρ M =Density of Mixture
ρ S =Absolute Density (not Bulk Density) of Solute
ρ L =Density of Solvent
However, both of these common models used make erroneous assumptions. In the Non-Linear Model, it is assumed that the volumes of the components are completely additive, meaning that the components are completely insoluble in each other. This is very rarely the case. Most real world cases employ a solution of soluble or partially soluble solutes. In these cases, this model tends to overestimate the solution's concentration. In the Linear Model, the assumption fails because it does not compensate for the molecular interactions between the solute and the solvent. In either case, the assumptions often introduce enough error to render the results useless, as shown in Table 1.
TABLE 1
Examples of Model Inaccuracies.
NON-LINEAR
NON-LINEAR
MODEL
MODEL
LINEAR MODEL
LINEAR MODEL
SOLUTION
CONC.
CONCENTRATION
% ERROR
CONCENTRATION
% ERROR
sodium chloride
26.0%
30.3%
16.4%
16.7%
35.7%
barium chloride
26.0%
29.5%
13.4%
9.8%
62.4%
magnesium sulfate
26.0%
36.6%
40.8%
17.8%
31.4%
ferric sulfate
40.0%
45.7%
14.4%
21.4%
46.5%
calcium chloride
40.0%
62.5%
56.2%
47.6%
19.1%
sodium thiosulfate
40.0%
69.2%
72.9%
57.4%
43.4%
ferric chloride
50.0%
55.9%
11.7%
31.1%
37.8%
potassium carbonate
50.0%
62.3%
24.6%
41.9%
16.2%
sodium hydroxide
50.0%
64.9%
29.8%
46.5%
7.0%
SUMMARY OF THE INVENTION
The present invention provides a new method for predicting the concentration of a solid/liquid or liquid/liquid mixture by use of the mixture's true density. This method makes use of a model, referred to herein as the Concentration-Density Model, which is an improvement over current methods of relating a mixture's concentration and density. This model introduces a novel concept referred to as the Additive Volume Coefficient (AVC), which reflects the change in volume that occurs after dissolving or mixing a solute into a solvent. The AVC is an important concept and provides this method with advantages over current technology.
The present invention provides a more accurate measurement of concentration than current technologies, and applies to a wider range of applications. As a result, the present invention, when coupled with an on-line measurement of solution density, provides accurate, continuous, real time feedback of a process fluid's concentration. This measurement is valuable to various industries in that it can assist manufacturers in effectively monitoring and operating their processes. Specifically, this data can be used, based on the manufacturing process, to do such things as:
1) control a known process fluid to a targeted concentration, e.g. in a paper coating process,
2) verify on-line the accuracy of batchwise or continuous ratio blends such as food products (ketchup, mayonnaise, syrup), personal care products (skin cream, shampoo), paints, petroleum blends, etc., and
3) eliminate excessive empirical work necessary with density monitoring process control systems.
The present invention is an improvement in that it more accurately converts a measured mixture density (ρM) to concentration (m) through the formula: m = 1 ( 1 - ρ L ∑ i = 1 n k i x i ( ρ S ) i ) - ρ L ( 1 - ρ L ∑ i = 1 n k i x i ( ρ S ) i ) ( 1 ρ M )
wherein ρL is the (temperature-dependent) density of the solvent, k i is the Additive Volume Coefficient for each solute, x i is the weight-% dry for each solute, (ρ S ) i is the (temperature-dependent) density of each solute, and ρM is the (temperature-dependent) density of the mixture.
Advantages of the present invention will become more apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific Examples are given by way of illustration only. Various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will be more fully understood from the detailed description given hereinbelow and from the accompanying drawings. These drawings are provided by way of illustration only, and thus do not in any way limit the present invention.
FIG. 1 graphically depicts the concept of the Additive Volume Coefficient.
FIG. 2 is a schematic representation of an industrial coating line having an on-line measurement system in accordance with the present invention integrated into it.
FIG. 3 is a schematic representation of a fruit canning line having a Distributed Control System operating in accordance with this invention.
DETAILED DESCRIPTION OF THE INVENTION
The present invention provides a new method for predicting the concentration of a solid/liquid or liquid/liquid mixture by use of the mixture's true density. This method provides a more accurate concentration measurement to a wider range of applications than any one current method or technology. It consists of theoretically determining the linear relationship between a mixture's concentration and density with the aid of a model referred to herein as the Concentration-Density Model.
The Concentration-Density Model is founded on the basic and straightforward principle that the volume of a mixture (slurry or solution) is different from the combined original volumes of the mixture's components if any level of solvency exists between these components. This Model incorporates the novel concept referred to herein as the Additive Volume Coefficient (AVC), which quantifies the change in volume that occurs after dissolving or mixing a solute into a solvent. As will be seen below, this Model uses a measurement of the mixture's density and the composition of the solutes in the mixture to calculate the mixture's concentration. For ease of practice, it is assumed that an accurate measurement of mixture density is provided.
Concentration-Density Model Factors:
k i =Additive Volume Coefficient for i th solute component.
ƒ(conc., temp.)
x i =Solute mass fraction of total solute mixture.
(ρ S ) i =Density of it solute, which is temperature dependent.
ρ L =Density of solvent, which is temperature dependent.
ρ M =Density of mixture, which is temperature dependent.
m=Concentration (expressed as a fraction).
V M =Volume of mixture.
V S =Volume of solutes in mixture.
V L =Volume of solvent in mixture.
C i =Coefficient of Thermal Expansion for i th solute component.
C L =Coefficient of Thermal Expansion for water.
C M =Coefficient of Thermal Expansion for the mixture. ∑ i = 1 n Δ m i = Concentration correction caused by density variation due to a temperature difference between the production temperature and the density reference temperature .
CONCENTRATION-DENSITY MODEL (Multi-component Systems):
The basic principle of the model is simple and straightforward. The volume of a mixture (slurry or solution) is different than the original volumes of the mixture's components, if any level of solvency exists between these components. This can be expressed as:
V M =V S +V L Eq.6
For one unit of mixture mass, it can directly be obtained that the volumes of mixture and liquid are V M = 1 ρ M and V L = ( 1 - m ) ρ L ,
respectively. As for solutes, their volume, when in the mixture, is expressed by: V S = k 1 x 1 m ( ρ S ) 1 + k 2 x 2 m ( ρ S ) 2 + Λ + k n x n m ( ρ S ) n = m ∑ i = 1 n k i x i ( ρ S ) i Eq . 7
From Eq. 6 and Eq. 7 above, we have: 1 ρ M = m ∑ i = 1 n k i x i ( ρ S ) i + 1 - m ρ L Eq . 8
By solving Eq. 8 above, the concentration in the mixture can be derived as: m = ρ M - ρ L ρ M ( 1 - ρ L ∑ i = 1 n k i x i ( ρ S ) i ) Eq . 9
Eq. 9, above, can be rewritten as: m = 1 ( 1 - ρ L ∑ i = 1 n k i x i ( ρ S ) i ) - ρ L ( 1 - ρ L ∑ i = 1 n k i x i ( ρ S ) i ) ( 1 ρ M )
where: Slope = 1 ( 1 - ρ L ∑ i = 1 n k i x i ( ρ S ) i ) and
y - Intercept = ρ L ( 1 - ρ L ∑ i = 1 n k i x i ( ρ S ) i ) Eq . 10
Eq. 10, above, indicates that concentration is linearly proportional to the inverse of the mixture density. This relationship has a slope and y-intercept which is dependent on the Additive Volume Coefficient (AVC), the composition of the solutes, and the density of all mixture components.
Since the AVC is a function of concentration and temperature, and density is a function of temperature, compensations may be made to Eq. 10, if necessary, for changes in concentration or temperature. This would be done by differentiating Eq. 10 with respect to the variable(s) in question. For example, the effects of temperature on the density of the solution components can be compensated for by incorporating the relationship between density and temperature:
(ρ i )= C i (Δ T ) Eq.11
By differentiating Eq.10 with respect to ρ as a function of T, we can estimate it's influence on the mixture's concentration as: ∑ i = 1 n Δ m i = - ρ L ∑ i = 1 n k i x i c i ( ρ S ) i 2 ( 1 - ρ L ∑ i = 1 n k i x i ( ρ S ) i ) 2 ( Δ T ) + ( ρ L ) 2 ∑ i = 1 n k i x i c i ( ρ S ) i 2 ( 1 - ρ L ∑ i = 1 n k i x i ( ρ S ) i ) 2 ( 1 ρ M ) ( Δ T ) + c L ∑ i = 1 n k i x i ( ρ S ) i ( 1 - ρ L ∑ i = 1 n k i x i ( ρ S ) i ) 2 ( Δ T ) - c L ( 1 - ρ L ∑ i = 1 n k i x i ( ρ S ) i ) 2 ( 1 ρ M ) ( Δ T ) + ρ L ( 1 - ρ L ∑ i = 1 n k i x i ( ρ S ) i ) 2 ( c M ρ M 2 ) ( Δ T ) Eq . 12
Yet, even in it's most basic form (Eq. 10), ignoring the effects of concentration and temperature, this model requires inputs other than the measured density. These additional inputs consist of:
1) the density of the mixture's solvent,
2) the true density of each solute, liquid or solid, within the mixture,
3) the composition of the solute mixture, and,
4) the AVC for each solute within the mixture.
The density of the mixture components are constants, and are usually available from a variety of sources.
The composition of the solute mixture, on the other hand, requires some knowledge from manufacturing. In many manufacturing environments, the mixture being measured has been made internally, and therefore, the composition of each solute is known.
The AVC is introduced as a constant unique to a solute-solvent mixture at a constant concentration and temperature. As such, this AVC need only be determined once for each raw material in use. Over time, as AVC's are documented, obtaining these data would be no more difficult than obtaining component densities.
FIG. 1 graphically illustrates the concept of the Additive Volume Coefficient. Completely insoluble components have volumes which are completely additive. The example shows 1 unit volume of sand and 2 unit volumes of water equaling 3 unit volumes of mixture. And partially or completely soluble components have volumes which are less than additive. Shown is an example of CarboxyMethylCellulose (CMC) and water. CMC is partially soluble in water. The example shows 1 unit volume of CMC in 2 unit volumes of water resulting in less than 3 unit volumes of mixture.
Specific examples can be found in Table 2.
TABLE 2
Volume change and AVC examples.
SOLUTE
SOLVENT
(NON-LINEAR MODEL)
SOLUTE
SOLVENT
VOLUME
VOLUME
ADDED VOLUME
ACTUAL VOLUME
AVC
nickel sulfate
water
1.1
96.0
97.1
95.9
−0.110
sodium hydroxide
water
3.8
92.0
95.8
91.8
−0.043
magnesium sulfate
water
9.8
74.0
83.8
77.0
0.309
sodium thiosulfate
water
24.0
60.0
84.0
72.2
0.509
calcium chloride
water
21.9
60.0
81.9
71.5
0.528
potassium carbonate
water
21.8
50.0
71.8
64.8
0.679
sodium chloride
water
12.0
74.0
86.0
83.5
0.791
This AVC, and a method for determining this AVC, is defined below for a two component system. This method can also be applied to multi-component systems.
Additive Volume Coefficient Factors:
k=Additive Volume Coefficient for a solute component.
ƒ(conc., temp.)
m=The concentration of the mixture, measured via a lab method.
VT b =Total volume of the substance before mixing.
VT a =Total volume of the substance after mixing.
W S =Mass of solute.
W L =Mass of solvent.
ρ S =Density of solute. KNOWN
ρ L =Density of liquid (solvent). KNOWN
ρ M =Density of mixture.
V S =Volume of solute to be mixed.
V L =Volume of liquid (solvent) to be mixed.
METHOD of DETERMINING AVC
FOR A SINGLE-PHASE SOLUTE (Solid or Liquid):
Measure the mass of solvent (W L ).
Calculate the volume of solvent to be mixed: V L = W L ρ L Eq . 12
Measure the mass of solute (W S ).
Calculate the volume of solute to be mixed: V S = W S ρ S Eq . 13
Calculate the total volume of the substances before mixing (VT b ):
VT b =V L +V S Eq.14
Mix the solute and solvent.
Measure the density of the mixture to determine the total volume of the substances after mixing (VT a ): VT a = W L + W S ρ M Eq . 15
Calculate the additive volume coefficient (k): k = 1 - VT b - VT a V S Eq . 16
METHOD of DETERMINING AVC
FOR A DUAL-PHASE SOLUTE (Solute in a Slurry Form):
Measure the concentration of the slurry (m).
Calculate the volumes of solvent (V L ) and solute (V S ), based on one unit mass of slurry: V L = 1 - m ρ L Eq . 17
and V S = m ρ S Eq . 18
Determine the total volumes of the substances before (VT b ) and after (VT a ) mixing via: VT b = 1 - m ρ L + m ρ S Eq . 19
and VT a = 1 ρ M Eq . 20
Calculate the additive volume coefficient (k) as: k = 1 - VT b - VT a V S Eq . 21
Neglecting the effects of temperature on AVC, a relationship between the AVC of a solute-solvent pair and the concentration of the solute-solvent mixture can be developed by determining the AVC of the mixture at multiple concentrations and using regression analysis. Advancing this study to also include the effects of temperature would develop a relationship expressing AVC as a function of temperature and concentration. However, within a production environment these variables (temperature, concentration) likely operate within a narrow range. Therefore, the AVC can likely be simplified to be dependent on one or none of these variables for a specific application.
EXAMPLES
Example 1
% Solids Control in Coating Substrates
One application of this invention is the on-line determination of the % solids of a coating slurry applied to a substrate such as a paper web. This coating % solids data is then used to more efficiently control the application of the coating slurry onto the paper web. This benefit is realized due to the fact that % solids is often the primary coating property affecting the quantity of coating being applied to the paper web. As the accuracy of the measurement of coating slurry % solids is improved, the control of the quantity of this coating slurry is also improved.
Specifically, given a production environment in which the following production information is available to an on-line control system:
1) the dry coating component ratio,
2) the relationship between the Additive Volume Coefficient of each coating component and the concentration of the component in the mixture,
3) an on-line measurement of the density of the coating slurry, and,
4) the true density of each coating solid or solute; the following calculations are to occur within the control system to determine the coating slurry % solids:
A. Determine the Concentration-Density Relationship.
B. Estimate the coating slurry % solids.
C. Calculate the AVC for each component based on the estimated % solids.
D. Use an iteration process (e.g. Newton's Method) to determine the actual % solids of the coating slurry. (In manufacturing environments where the AVC can be accurately reduced to a constant, the use of Newton's Method is not necessary. This significantly reduces the calculations involved.)
Broadly speaking, this application of the present invention provides a method of monitoring a continuous coating of a substrate with solids delivered in a slurry of water. A first step in the present application comprises setting a target solids weight-% for the slurry. That is, in order to practice the present invention, one must determine what the solids weight-% in the coating slurry should be in order to provide a coated substrate having the desired properties. Having determined that target solids weight-%, one proceeds to provide a continuous industrial coating line with appropriate volumes of water and with appropriate amounts of the solid or solids with which it is desired to coat the substrate.
In order to implement the present invention, one may modify a conventional industrial coating line by inserting an on-line density measurement system into it. Referring to FIG. 2, industrial coating line 1 comprises coating run tank 4 , pump 5 , and coating slurry bath 14 . These elements are linked by piping 7 . A roll 8 is partially immersed in bath 14 , and substrate 9 travels around the roll through the bath where it contacts coating slurry 13 . On-line density measurements 6 , along with the composition of the coating slurry, are fed as inputs into distributed control system 10 .
In accordance with the present invention, the distributed control system 10 converts these inputs to the solids weight-% of the coating. This, in turn, is compared to the target coating solids weight-% for the slurry. If there is a difference, the distributed control system 10 adjusts coating inflows 2 and 3 with flow control valves 11 and 12 as appropriate to correct this difference.
This Example represents use in one particular coating process. However, those skilled in the art will realize that this invention can be applied similarly to virtually any current coating method.
Example 2
Minimized Empirical Efforts in Controlling Syrup Makedown
Another application of this invention is the on-line determination of the concentration of sugars dissolved in water, commonly referred to as °Brix. This measurement is used to control the process of making syrup such as that used with canned fruit. Such a control provides the food manufacturer with the ability to control the product's sugar content. This provides the customer with a consistent taste over time, and/or the knowledge of a sugar content maximum, which is important to those with certain health conditions.
Current methods of measuring °Brix involve converting the measurement of syrup density to °Brix. This can be done using long-standing conversion tables available in the public domain. When incorporated into a control system, these conversions can occur on-line, thus providing real-time °Brix measurement. However, these conversion tables were developed using a sugar solution which was likely different than that being processed. This introduces a certain amount of error during the conversion of density to °Brix.
To overcome this error, manufacturers can re-develop this conversion relationship for their specific products. However, this process can be very time-consuming. When many such relationships must be developed, the time requirements involved may be prohibitive.
When used in conjunction with an on-line control system as described in Example 1, this invention eliminates the time-consuming need for manually developing these conversion relationships while providing a method for accurately converting density to °Brix.
The first step in this application comprises setting a target °Brix for the dilute syrup. Next, the flows of concentrated syrup and dilution water are controlled to maintain the dilute syrup at the targeted °Brix.
Referring to FIG. 3, concentrated syrups 31 , 32 , and 33 are blended together as a concentrated mixture 4 in a ratio controlled by flow valves 43 . The concentrated mixture travels through pump 35 to mixing tee 36 where it is blended with water from supply header 40 . This dilute mixture travels through static mixer 38 to an on-line density meter 39 .
The distributed control system 41 then converts the inputs to °Brix in accordance with the present invention. This, in turn, is compared to the target °Brix. If a difference exists, the distributed control system adjusts the flow control valves 33 and 34 to correct the discrepancy.
The invention being thus described, it will be evident that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be apparent to one skilled in the art likewise constitute a part of the present invention. | The present invention provides an improvement to the two, inaccurate, traditional approaches relating concentration to density. The first of these assumes that the solute is completely insoluble in the solvent; the second is based on a soluble solute. The present improved relationship is referred to as the CONCENTRATION-DENSITY MODEL. This model allows for a theoretical determination of the concentration-density relationship for a multi-component solid/liquid or liquid/liquid mixture. Included in the Concentration-Density Model is a new concept referred to as ADDITIVE VOLUME COEFFICIENT (AVC). This concept compensates for the fact that the net volume of a mixture does not always equal the sum of the volumes of each component. This improved Concentration-Density Model provides fluid-handling manufacturers with a method for accurately determining a mixture's concentration on-line with the aid of current density measurement instrumentation. By allowing for accurate concentration determination in manufacturing scenarios where such measures were previously impractical, the present invention enables improved control of the manufacturing process. | 6 |
BACKGROUND OF THE INVENTION
This invention lies in the field of inks for recording devices wherein ink is ejected from a recording head towards a record member.
Techniques are known for recording information on recording carriers (or record members) by means of a controlled spraying of an ink liquid wherein the recording head is in spaced relationship to the recording carrier (or record member). In such a technique, the ink liquid is ejected droplet by droplet under pressure from one or more nozzles in a direction towards the record member. The art appreciates how to convey the ink liquid to the recorder head under low or high pressure, as desired, and also how to apply the ink liquid from a recorder head being maintained under a slight vacuum. The ink is ejected from a recorder head by means of an electrostatic field, or, by means of space alterations in the ink ejection chamber of the recorder head. The ink of the present invention, for example, can be utilized in an apparatus such as is provided in the German Offenlegungsschrift No. 2,543,451 (corresponding to U.S. application Ser. No. 727,038 filed Sept. 27, 1976) now abandoned.
A source of problems in the utilization of such ink-using recording devices is the prior art inks utilized. The ink used should form a nonfading deposit on the record member which is as rich in contrast as possible relative to record member background areas, yet the ink should not plug the record head nozzles even after long periods of apparatus disuse.
A number of inks are known for liquid recording wherein it is desired to have an ink viscosity below 10 centipoises, or even under 5 centipoises, at a surface tension of 40 through 50 dynes per centimeter. Great importance was allotted to the creation of inks having a viscosity below 10 centipoises. Moreover, apparatus also became known pointing to the need therefor, such as would enable, for example, the recording onto smooth surfaces and indeed thereby achieve a recorded surface etched with an aggressive ink component.
BRIEF SUMMARY OF THE INVENTION
More particularly, the present invention relates to ink compositions. Such compositions are useful in recording devices, particularly recording devices wherein the ink is ejected under pressure towards a record member from a recording head located in spaced relationship to the record member. The ejection chamber of the recording head has subatmospheric pressures maintainable therein. In such ink compositions of this invention, a dyestuff which is acidic is utilized in combination with a solubilizing agent which is alkaline in effect. Both such dyestuff and such solubilizing agent are dissolved in a solvent system having a large dipole moment and having a hygroscopic behavior which compensates for solvent evaporation.
It is a primary object of the present invention to provide an ink suitable for the recording of information onto normal writing paper and in which a plugging of the recording nozzles is substantially completely eliminated with highest possible reliability. A plugging of recording nozzles interrupts the recording process. In directly operated recording machines, a removal of any plugging of nozzles can be accomplished by operating personnel. However, even in such machines such an interference is very inconvenient, while in recording devices which are not continuously monitored, and which are not operated by operating personnel directly, such as, for example, in data or teletype machines, no allowances can be made for breakdowns of the recording device caused by a plugging of pringing nozzles. Monitoring the functioning efficiency at this point is extremely difficult, although possible. Because at least those teletype machines connected to a public teletype network always have to be ready for immediate operation, and because typically such machines are also in a non-monitored condition, the breakdown potential probability of the recorder heads therein must be reduced to a minimum.
In accordance with the present invention, an ink is provided, which, has improved non-plugging characteristics even with different normal surrounding influences, yet does not compromise the functioning efficiency of a recorder head. At the same time, such ink is capable of producing a stable recorded image which is rich in contrast on conventional record members.
Other and further aims, objects, purposes, advantages, uses, and the like for the present invention will be apparent to those skilled in the art from the present specification.
DETAILED DESCRIPTION
In ink compositions of this invention, the dyestuff acid and the alkaline acting dissolving (solubilizing) agent are both dissolved in a solvent system. The interrelationship between these materials is such that the dissolving agent at least compensates for the acidic effect of the dyestuff acid and thus dissociates the dyestuff acid in the solvent medium. The solvent medium is characterized by having a large dipole moment and by having a hygroscopic behavior compensating evaporation. The dyestuff acid employed in the ink composition is capable of supplying a stable recorded image which is rich in contrast on a conventional or normal record member. The combination of components in an ink composition is such that a plugging of recorder head nozzles, and also of any filters utilized, is substantially completely prevented with the greatest safety possible. By employing a solvent composition having a high dipole moment, a dissolution of the dyestuff acid in the solvent composition is achieved with greatest possible safety thereby minimizing the possibility of dyestuff particles being present which can lead to a nozzle plugging. By having a solvent composition with hygroscopic behavior as indicated, the evaporation loss inherently associated with a solvent system is compensated for so that a desired viscosity for an ink composition of this invention is maintained.
In accordance with a preferred embodiment of the present invention, an ink composition exhibits a viscosity of from about 15 to 100 centipoises (measured at a surface tension of about 40 to 50 dynes per centimeter at ambient pressures and temperatures.) A viscosity of about 20 centipoises, so measured, is particularly advantageous. Ink compositions of this invention with such viscosity values are particularly effective for use in recording devices wherein the ink is ejected from the recorder head by altering the space volume in the recorder head, as in such apparatus the droplet frequency of the ejected ink stream from the nozzle (or nozzles as the case may be) can be advantageously regulated by means of the inherent dampening action associated with such an ink composition of this invention.
In ink compositions of the invention, it is additionally desirable to employ a solvent system wherein the individual components of the solvent system have respective viscosities whose values lie close to the viscosity associated with a solvent system composition. By altering the individual solvent components, for example, by evaporation, or by temperature fluctuations, or similar influences, the ink composition viscosity desired is thus not substantially altered.
Various combinations of solvents can be employed. To obtain the desired combination of properties, one can employ a mixture of water and diethylene glycol. A more preferred solvent composition comprises diethylene glycol and dimethylsulfoxide. Like water, dimethylsulfoxide has a high dipole moment and is thus a good solvent agent for use in the present invention. Moreover, dimethylsulfoxide is hygroscopic and has a low evaporation rate. Also, it penetrates paper particularly rapidly, which is desirable from the standpoint of the present invention since many records members involve paper. Also, like water, dimethylsulfoxide approximately corresponds in viscosity to water and is miscible in all proportions with diethylene glycol.
The viscosity of a solvent composition comprised of diethylene glycol and dimethylsulfoxide is still so low at -20° C. that an ink composition of this invention using such a solvent composition can still be used for a recording operation. Even at temperatures of -70° C. such a solvent composition is not yet frozen but rather remains only viscous so that indeed while no recording operation is possible, as when such a solvent system is used in an ink composition of the present invention, nevertheless, no destruction of the recorder head need be feared. Such two solvents, diethylene glycol and dimethylsulfoxide, have relatively closely adjacent viscosity values, over the broad scale of possible viscosities, with the viscosity of dimethylsulfoxide being about two centipoises while the viscosity of diethylene glycol is about 38 centipoises, measured as above indicated. Furthermore, a composition of diethylene glycol and dimethylsulfoxide has an advantageous evaporation factor yet is also hygroscopic so that evaporation losses are compensated for during use of an ink composition of this invention in recording apparatus of the class indicated above.
Furthermore, the solvent compounds dimethylsulfoxide and diethylene glycol have in combination with one another a low solubility for gases, particularly air, and have a very low vapor pressure, as is desirable in the preferred practice of the present invention. Thus, a gas accumulation in an ink composition for use in recording devices of the class above indicated is detrimental to the operation thereof because gas tends to cause a cavitation effect within the recorder head when the interior volume thereof is increased during routine operation of the apparatus.
A preferred dissolving agent for use in the practice of the present invention is sodium carbonate. An alternative but also preferred dissolving agent is triethanolamine. Both of these agents have an alkaline effect whereby the dyestuff acid concentration in a solvent medium can be quantitatively regulated, as desired.
In general, an ink of this invention as characterized above typically comprises on a 100 weight percent total ink basis:
(A) From about 2.5 to 12 weight percent of a dyestuff acid, as characterized above,
(B) From about 1 to 20 weight percent of a dissolving agent such as characterized above, and
(C) From about 70 to 95 weight percent of such a solvent medium as characterized above.
Such a solvent medium has a dipole moment preferably of at least about 3.5 and an evaporation rate >1500.
Preferably a solvent medium comprises on a 100 weight percent total solvent medium basis:
(A) From about 25 to 40 weight percent of diethylene glycol, and
(B) From about 40 to 70 weight percent of dimethylsulfoxide.
For purposes of this invention, viscosity is measured about 20 [CP].
EMBODIMENTS
The present invention is further illustrated by reference to the following examples. Those skilled in the art will appreciate that other and further embodiments are obvious and within the spirit and scope of this invention from the teachings of these present examples taken with the accompanying specification.
EXAMPLE I
Dimethylsulfoxide is mixed with diethylene glycol to produce a solvent medium comprised of about 33.3 weight percent dimethylsulfoxide and 66.6 weight percent diethylene glycol on a 100 weight percent total solvent medium basis. This solvent medium has a dipole moment of about 3.5 Debye and an evaporation rate >1500.
Then, first about 1.2 weight percent of sodium carbonate, and thereafter about 2.8 weight percent dyestuff acid are dissolved in this solvent medium on a 100 weight percent total product composition basis. The dyestuff acid consists of A70-compounds. The product composition has a viscosity of about 20 centipoises.
EXAMPLE II
A solvent medium comprised of about 30 weight percent (3 volumes) diethylene glycol and about 50 weight percent (5 volumes) dimethylsulfoxide, on a 100 percent total solvent composition basis, is prepared by admixing one compound with the other. The resulting solvent medium has a dipole moment of about 3.5 Debye and an evaporation rate >1500.
Then, first about 10 weight percent of triethanolamine, and thereafter about 10 weight percent of dyestuff acid are dissolved in such solvent medium on a 100 weight percent total product composition basis. The dyestuff acid consists of A70-compounds. The product composition has a viscosity of about 20 centipoises. | An ink for a recording device, particularly for an ink recording device in which the ink is given off by means of pressure in a direction towards the recording carrier by a recorder head, which is spaced from the record member, and in which a vacuum is formed in the ejecting chamber. | 2 |
BACKGROUND OF THE INVENTION
The invention relates to a fuel injection pump having an adjusting lever for injection quantity and an adjustable stop for setting idle rpm. In a known fuel injection pump of this kind, an adjustable screw which can be locked by a nut acts as a stop for the minimum injection quantity, that is, a quantity such as is desired for idling. The provision of the larger injection quantities necessary during warmup is then effected by specialized means in the governor, which either does not permit an arbitrary variation of this minimum quantity or permits such a variation to be made only with substantial difficulty.
OBJECT AND SUMMARY OF THE INVENTION
It is an object of the invention to provide a fuel injection pump having the advantage over the prior art that the minimum-quantity adjustment is effected simply, inexpensively and in an arbitrarily controllable manner.
It is another object of the invention to provide a stop wherein a differently shaped face may be selected for different internal combustion engines and can be installed on a mass-produced pump in a modular manner.
It is a further object of the invention to provide an adjustment means whose installation is extremely simple and, as installed, is wear-resistant. This results because the forces are exerted in the axial direction so that no tilting moment results, and thus there is extremely little wear because the shaped surface area is so large.
It is still further object of the invention to provide that basic initial adjustment of the apparatus may be undertaken without thereby influencing the established governor characteristics of the pump governor.
It is yet another object of the invention that the minimum fuel injection quantity be determined by a stop which is variable in accordance with engine characteristics or with the characteristics of the environment within which the engine operates.
The invention will be better understood and further objects and advantages thereof will become more apparent from the ensuing detailed description of a preferred embodiment taken in conjunction with the drawing.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 shows an injection pump having the stop apparatus shown in sectional form; and
FIG. 2 is a view of the stop apparatus along the direction indicated by the arrow II, but rotated by 45° and showing schematically the bimetallic spiral element not otherwise visible.
DESCRIPTION OF THE PREFERRED EMBODIMENT
An adjusting lever 3 is disposed on a shaft 2 in a fuel injection pump 1. The rotary position of this adjusting lever 3 determines the fuel injection quantity and this quantity can be arbitrarily adjusted by the driver of the vehicle in which the internal combustion engine is provided and so equipped. An electric governor can be controlled by means of the shaft 2 or, as in the case of a mechanical governor, for instance, the initial tension of the governor spring can be varied. The rotary position of the adjusting lever 3 is defined by stops, with a first stop 4 in principle defining the minimum quantity and a second stop 5 defining the maximum quantity. A restoring spring 6 biases the lever 3 toward the position of stop 4 to provide the minimum supply quantity, which corresponds normally to that quantity which is desirable at idling.
To provide a minimum fuel quantity which can be varied by a stop means in accordance with engine operating parameters, an angled tongue 7 is provided on the lever 3 by securing elements 8, and a stop screw 10 which can be locked in position by a nut 9 extends therethrough. This stop screw 10 is arranged to cooperate with a stop apparatus 11, which is provided with a cam face 12 as a stop for the stop screw 10 on one extremity thereof and lying in opposed spaced relation to the stop screw 10. This cam face 12 is rotatable in a plane extending perpendicular to the pivotal plane of the lever 3. As best shown in FIG. 1, this cam face 12 is shown rotated by 45° for the sake of better visibility. In its actual installed position, the screw 10 would be abutting the cam face 12. The cam face 12 is provided as a surface of a collar cam disc element 13, which is mounted via a plastic disc 14 on the end face of a sleeve 15, which in turn is secured on the injection pump 1 by a mounting bracket 16. The collar element 13 is secured by a screw 17 on a shaft 18, which is supported in the end wall of the sleeve 15 and has a rotation lever 19. This rotation lever 19 is coupled via a pin 20 at one extremity thereof with a bimetallic spiral 21 and at the other extremity with a spiral spring 22. The spiral spring 22 is firmly connected at a zone 23 via its inner end with the sleeve 15. The inner end of the bimetallic spiral 21 is also firmly connected with the sleeve 15, being secured via a screw 24 to a cap 25 of the sleeve 15, the cap 25 being secured via screws 26 to the sleeve 15. A heating element 27 is disposed in this cap 25 and can heat the bimetallic spiral 21 through one surface and this heating element is provided with an electrical connection 28. FIG. 2 is a view of the stop apparatus 11 seen from the end face in the direction indicated by arrow II. Because the spiral elements disposed in the sleeve 15 are not normally visible from the outside, these elements are indicated by broken lines for the sake of clarity in explaining the function of the stop apparatus 11. The bimetallic spiral 21 and the spiral spring 22 engage the pin 20, which is firmly connected with the lever 19, from opposite directions; that is, spiral spring 22 engages the pin 20 in the manner of a right-handed screw, while the bimetallic spiral 21 engages the pin 20 in the manner of a left-handed screw, each direction being as seen in the drawing. In FIG. 2, two positions are shown for the pin 20. The angular difference between these positions results in a corresponding difference in height of the stop apparatus 11; this movement is translated to the adjusting lever 3 of the injection pump 1, so that the lever 3 moves a corresponding angular difference. To provide the desired stop value, the bimetallic spiral 21 can be heated to a greater or lesser extent, so that the pin 20 can assume any desired position between the two illustrated positions, especially when the ambient temperature is very low during engine starting.
Alternatively, the invention comprehends influencing the position of the pin 20 by providing the cam disc element 13 with various inclinations on the cam face 12. Because the fuel quantity adjustment is effected by means of heating, the occasions upon which heating occurs may be selected quite freely, for instance, during warmup of the engine, upon a change in ambient air pressure or during the operation of an air conditioner, it may be desirable for such heating to be performed. Depending upon the requirements placed upon the engine, the idling rpm thus can be increased or reduced, depending upon the particular inclination abutting the stop screw 10 provided by a change in the direction imparted to the cam disc 13.
The foregoing relates to a preferred exemplary embodiment of the invention, it being understood that other embodiments and variants thereof are possible within the spirit and scope of the invention, the latter being defined by the appended claims. | A fuel injection pump is disclosed in which the minimum injection quantity or idling rpm is determined by an arbitrarily adjustable stop. This stop is adjusted via a heatable bimetallic spiral, which acts counter to a spiral spring for the purpose of force compensation. | 5 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of, and claims the benefit under 35 U.S.C. §120 from, nonprovisional U.S. patent application Ser. No. 11/838,768, entitled “Video And Content Controlled Backlight,” filed on Aug. 14, 2007, the subject matter of which is incorporated herein by reference. U.S. patent application Ser. No. 11/838,768 claims the benefit under 35 U.S.C. §119 from U.S. provisional patent application Ser. No. 60/837,710, filed on Aug. 14, 2006, the subject matter of which is incorporated herein by reference.
TECHNICAL FIELD
[0002] The present invention relates to a display device and a backlight component thereof.
BACKGROUND INFORMATION
[0003] Liquid crystal displays (“LCDs”) contain a backlight, which is the source of light that enables the LCDs to display images and texts. The liquid crystal that is in the display acts as a shutter to let the light through or not based on the command that is delivered by a corresponding control chip. Most LCDs use a cold cathode fluorescent light (“CCFL”) tube as the light source. CCFL is on all the time when the LCD is turned on. The video signal, or the content, or the image that is shown on the LCD is created by the controlling the orientation of the liquid crystal elements in the display panel.
[0004] The special glass panel of the LCD creates the colors based on the light filtering mechanism of the films on the glass panel. The light that is generated by the CCFL is white light in most of the LCDs, which is provided behind the glass panel, where the front side is the side of the viewer.
[0005] CCFL is energy efficient. However due to the use of hazardous materials in CCFL, the industry is phasing out CCFL from the backlight application. Also the CCFL-based backlight is kept turned on continuously even if no image is displayed. Furthermore the light is slow to turn on or off, thus it is difficult to switch it on or off based on the image.
[0006] However, it would be desirable to turn the backlight off if no image is being displayed, or for dark scene, or for a dark image. This would save energy, which would especially beneficial for battery operated portable products. Furthermore the CCFL backlight lights the back of the whole display and has difficulty in providing zone backlighting, or fractional backlighting based on the image to be displayed. Namely if on one side of the display the image is a dark image, than that side does not need the backlight on. With CCFL technology it is difficult to only light the needed area or zone, and especially at video image rate (30 to 60 frames a second) sine CCFL cannot be turned on or off at fast rates.
[0007] Alternatively the industry has been embracing the use of white light emitting diodes, (“LEDs”) for backlights. Rather than having a CCFL light bulb, one uses a plurality of LEDs as the light source. However this solution is more costly than present CCFL backlights. The LED backlighting is also less energy efficient than the CCFL light source. Also the present so-called “white LEDs” do not emit pure white light, nor is it as white as the CCFL based backlight. Namely the white color is not truly optically white thus the resultant color quality of the image is poor. This LED solution might be adequate for LCDs for simple telephones, or instruments that do not need to display color pictures, or video, or television, (“TV”) programs. However for LCD for color TVs, video displays, and for color imagery, a better solution is needed.
[0008] With this need the industry has resorted to the use of RGB LED technology, namely LED's with the three distinct colors, red green and blue (similar to the RGB concept in the CRT color TVs). According to color physics, one can generate for the human eye, the colors of the spectrum with the combinations of RGB. For example, white is created by turning on the three colors at the desired intensity, the red green and blue, which then appears to the eye as white. These techniques are well known for persons trained in the art, from the early days of CRT based color TV and color art graphics.
SUMMARY
[0009] The present invention relates to display devices, e.g., LCDs, using light emitting diodes. Current LCD panels commonly use CCFL technology. Generally, such LCDs use three primary colors (red, green, and blue) per pixel with no precise control on the brightness. Only an overall brightness control is possible by adjusting the CCFL backlight intensity. However, among other features, the present invention teaches the use of LEDs in the display devices. This enablers the separation of image contrast from image color and brightness. Image contrast can be fully controlled by the LCD panel acting as a simple off-on light shutter. A single off-on LCD light shutter pixel can control three colors using the LEDBK. More specifically, a single LCD light shutter pixel, which happens to be located in an area lit up by an LED cluster can control red, green, blue, or any color simply by adjusting the IRed Ym, IGreen Ym, or IBlue Ym (see FIG. 5 ). LCD panel thus used in conjunction with the LEDBK increases the total number of pixels controlled by three. In addition, varying the individual LED current varies the brightness.
[0010] By using the LCD displays as simple off-on light shutters per pixel, and by using the LEDBK to provide the needed colors, the LEDBK of the present embodiment increases the resolution of LCD panels by a factor of three. By increasing the LEDBK light output in panel areas needing bright light, and by reducing the LED current or turning off the LEDs in areas needing low light or darkness, the contrast of the LCD is increased. By only turning on the LEDs in areas where light output is needed, energy efficiency is increased.
[0011] In one embodiment, a display device includes a display panel and a backlight panel provided below the display panel and defining a plurality of regions. A first array of light emitting diodes (LEDs) is provided along a first direction, each LED of the first array being coupled to a first line. A driver is coupled to the first line to drive the LEDs coupled to the first line. A second array of LEDs is provided along a second direction, each LEDs of the second array being coupled to a second line. A lighting condition of the regions defined by the backlight panel is controlled by turning on or off the LEDs. The plurality of regions defines a matrix of regions having an X number of rows and a Y number of columns. Each region has at least one LED. Each region has at least one LED cluster.
[0012] In another embodiment, an array of light emitting diodes (LEDs) includes a first array of light emitting diodes (LEDs) provided along a first direction in a backlight panel of a display device, each LED of the first array being coupled to a first line; a driver coupled to the first line to drive the LEDs coupled to the first line; and a second array of LEDs provided along a second direction, each LEDs of the second array being coupled to a second line, wherein the LEDs are grouped in a cluster of at least three LEDs.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIGS. 1 and 2 illustrate an LED based a backlighting panel and a liquid crystal panel according to one embodiment of the present invention.
[0014] FIG. 3 illustrates a portion of the LEDBK for simplicity of illustration.
[0015] FIG. 4 illustrates a LEDBK having a light guide panel according to one embodiment of the present invention.
[0016] FIG. 5 illustrates an array of 12 LED clusters (Xn−2,Ym−1) to (Xn+1,Ym+1) in a matrix configuration according to one embodiment of the present invention.
[0017] FIG. 6 illustrates a portion of the matrix configuration of FIG. 5 according to one embodiment of the present invention.
[0018] FIG. 7 illustrates waveforms associated with driving the 12 LED clusters in FIG. 5 according to one embodiment of the present invention.
[0019] FIG. 8 illustrates signals used to generate images on a display panel according to one embodiment of the present invention.
[0020] FIG. 9 shows a block diagram of a decoder circuit 300 that is used to create the signals shown in FIG. 6 .
DETAILED DESCRIPTION
[0021] The present invention relates to the use of LEDs in a display device, e.g., LCDs. In one embodiment, an array of LED modules or clusters is used as a backlight of the LCD. Each of these modules or clusters comprises a plurality of LEDs of RGB that is suitable for generating white light. In one implementation, the module or cluster comprises RGBB (an extra blue LED in the cluster), or RGBYC (which in addition to the red green and blue, has a yellow and cyan LED), or RGBXYZ, where X is an additional color LED, Y is an additional color LED and Z is an additional color LED in a cluster. Based on the specific application, or specific use of the display, either for TV, or still photography, or display of art, one can select any LED combination in a cluster. For simplicity of the explanation, without limiting it to the discussed example, the present invention is described in using RGB LED clusters.
[0022] FIGS. 1 and 2 illustrate an LED based backlighting panel 80 and a liquid crystal panel 90 according to one embodiment of the present invention. The LC panel 90 is divided into a plurality of regions, e.g., 9 by 5. Similarly, the LED backlight panel 80 (“LEDBK”) corresponding to the LC panel 90 is divided into a plurality of regions, e.g., 9 by 5. An RGB LED cluster 82 is provided in each region of the LEDBK 80 . In one implementation, a white LED may be used in place of an LED cluster for each region. In another implementation, an LED cluster is not placed at each region, but at selected locations.
[0023] Each region is designated by X-Y coordinates. A top left region 84 is designated by X-Y coordinates as A 1 . The region A 1 in the LEDBK corresponds to a region A 1 in the LC panel. Similarly, each region in the LEDBK is assigned the same coordinates as the corresponding region in the LC panel. A display panel is formed by putting the LC panel 90 on top of the LED backlight panel 80 , thereby forming one LCD.
[0024] In the present embodiment, the LEDBK 90 includes one RGB LED cluster per region. Each region of the LC panel, however, may include one or more pixels. Each LCD pixel element is driven by the corresponding LCD driver element. The driver elements are chips that couple with transistors that are part of the LC panel. Since one RGB LED cluster has three LEDs, these three LEDs need to be driven for each region.
[0025] The electronic circuitry is designed accordingly. The electronic circuitry includes drivers for the LCD and drivers for the LEDBK. The drivers for the LCD contain the picture information needed to create a desired image on the LC panel. The drivers of the LEDBK need a subset of the corresponding information to light up the corresponding LED in the region.
[0026] The display device of the present embodiment may be seen as an LCD TV where the LC panel 90 is a screen of the LCD TV and the LEDBK panel 80 is its corresponding backlight panel. If part of the TV picture, e.g., region A 1 , is blue sky, then the blue LED within the cluster for region A 1 is turned on. In the same scene, if the region B 3 needs to display a green field, then the green LED in the cluster for region B 3 is turned on. Yet in another region all three LEDs may be turned on to provide a white light to provide a more complicated image. Similarly, in a frame by frame of the TV image, the LEDs in the regions of the LEDBK panel 80 may be driven frame by frame.
[0027] If no image is in a frame, then the LEDBK LEDs are turned off. In the present embodiment, the backlight is selectively turned on or off at different regions as desired, thus saving energy when compared to prior art. Accordingly, the operating life of the LCD type may be increased and also reduce the temperature of the LCD TV.
[0028] For cell phones applications, if just telephone numbers are displayed, e.g., regions A 1 and A 2 , of the panel 90 , then the LEDs in those regions may be turned on while the LEDs in other regions are turned off.
[0029] For TV applications, where the frames are refreshed typically at 30 frames per second, the LEDs are turned off and on at the corresponding rate generally. However if part of the video of the image does not change in some frames, then the LEDs in those regions may be kept turned off or on, which results in further energy saving.
[0030] In an LCD TV application of 19″ TV, the display panel may be made using 192 regions, composed of 12 rows and 16 columns. This would require 192 RGB clusters in total, or 576 LEDs. In a large LCD TV 40″ in size, the display panel may be divided into 20000 regions, 100 rows and 200 columns. This panel would use 60000 LEDs in the present embodiment, which would result in a significant picture quality improvement when compared with state of the art 40″ LCD TV.
[0031] In one embodiment, the LED cluster may have a different configuration other than RGB, e.g., RGBB, with four LEDs in a cluster or RGBCY with five LEDs per cluster, (with additional Cyan and yellow LEDs). Any other combination of color LEDs can be arranged in a cluster to create the desired color effect for the human eye.
[0032] Although the backlighting panel can be constructed with the same LED cluster throughout (herein referred to as “uniform LEDBK”), the panel may have a non-uniform LEDBK, where clusters of different LED combinations can be placed in different regions of the LEDBK to create the desired color, resolution, contrast or brilliance effect. For example, the edges of the LCD where the human eye generally does not focus onto, especially when viewing a large screen TV, the LED clusters of the LEDBK can be composed only with single white LED in these edge regions. On the other hand, the RGB LED clusters may be provided at the regions in the central viewing area of the screen. Alternatively, the peripheral or edge regions of the LEDBK are provided with RGB LED clusters, and the central viewing area are provided with more colorful RGBB or RGBCY LED clusters. Other combination of LEDs may be used according to application.
[0033] FIG. 3 illustrates a portion 100 of the LEDBK 80 for simplicity of illustration. The portion 100 has 12 regions, 4 columns (1 to 4) and three rows (A to C). A light diffuser layer made of glass or polymer is placed on top of the LED array and is part of the LEDBK panel. In one implementation, each region had a single RGB LED cluster, thereby providing LEDs in a matrix format. As before the image is either a picture or video in a TV application, or data or telephone numbers, or a picture or video in a typical mobile phone or PDA application.
[0034] According to an embodiment of the present invention, one can also design a display with a mode where the image can be created by the LEDBK LEDs without the image creation of the LC panel. This is effective when there is no image to be presented by a video signal, or any image by the LC panel. Namely the LC panel is in a transparent mode, letting the backlight through. It can be used for text, instruction, or data presentation, where the LEDs of the LEDBK are creating the image. This tends to be a lower resolution image but quite bright.
[0035] In one embodiment, the LED configuration of one, two, three, or four arrays are used to reduce the number of LEDs in the LEDBK and save manufacturing cost. The array may be a vertical array or a horizontal array or a combination thereof. In a 3-by-4 matrix, 12 LED clusters would be needed in a matrix configuration. However in an array configuration of one type, a total of 7 LED clusters are used. Three LED clusters A L , B L , and C L are provided in a column left side array. Four LED clusters 1 L , 2 L , 3 L , and 4 L are provided as a top array. In one embodiment, a single LED may be used instead of an LED cluster.
[0036] The three LED clusters A L , B L , and C L illuminate along the general horizontal direction as shown by the arrows 123 , 124 , and 125 . The LED clusters 1 L , 2 L , 3 L , and 4 L illuminate vertically down as shown by arrows 126 , 127 , 128 , and 129 . The LEDs illuminate into a light guide or light diffuser 121 that is made from glass, or a transparent polymer, plastic etc.. The light guide distributes the light and spreads it over the panel. The placement of the LED clusters and their intensity may be modified to obtain more light uniformity in the panel. For example, an array of LED clusters D L , E L , and F L may be added at the right vertical side and/or an array of LED clusters 5 L , 6 L , 7 L , and 8 L may be added at the bottom horizontal side. To keep the light intensity at region A 1 and region B 2 generally equal, the drive to LEDs AL and LEDs 1 L may be modified LEDs B L , and LEDs 2 L accordingly.
[0037] FIG. 4 illustrates a LEDBK 150 having a light guide panel 130 according to one embodiment of the present invention. Edges of the light guide panel 130 are shaped like divergent lenses 140 and 141 to spread the light from the LEDs into the guide. If only 7 LED clusters are used, the lens light collecting and distribution shape are formed in the areas corresponding to the locations of the LED clusters. Coated mirrors 130 and 131 are provided at the opposite sides to the LEDs, so that the light would be reflected back into the light guide panel as shown by arrows 132 and 133 .
[0038] According to the teachings of the present embodiment, different light intensities and different colors can be controlled for the 12 regions of the LEDBK panel using 7 LEDs. In bigger displays, the advantage of using the LEDs in an array configuration would be more pronounced. For example, a display defining 10 rows and 15 columns will need 150 LED clusters under a matrix configuration. However, as little as 25 LED clusters may be used under an array configuration described above. If the LED clusters are added on the right and bottom sides, only 50 LED clusters would be needed, which is ⅓ of the LED clusters needed under the matrix configuration.
[0039] FIG. 5 illustrates an array of 12 LED clusters (Xn−2, Ym−1) to (Xn+1, Ym+1) in a matrix configuration according to one embodiment of the present invention. These 12 LED clusters are provided for the 12 regions defined on a LEDBK panel. Each region has RGB LEDs. Each LED connected to a column line and a row line corresponding to its coordinate.
[0040] FIG. 6 illustrates a portion 200 of the matrix configuration of FIG. 5 according to one embodiment of the present invention. A driver is provided for each line to provide current/voltage. For example, row drivers 202 , 204 , and 206 are provided for lines Xn−2, Xn−1, and Xn, respectively.
[0041] FIG. 7 illustrates waveforms associated with driving the 12 LED clusters in FIG. 5 according to one embodiment of the present invention. As shown, the LED cluster (Xn−2, Ym) is first powered, then followed by (Xn−2, Ym−1), then by (Xn−2, Ym), and then by (Xn−2, Ym+1) in sequence. The row driver 202 drives VMAX to all of the LED cluster anodes connected to the line Xn−2 to enabling all three colors. Once enabled, a current applied to IRed Ym, IBlue Ym, or IGreen Ym will turn on the respective LEDs in the clusters. The actual light output of the LED is proportional to the current sunk by the respective Ym.
[0042] FIG. 8 illustrates signals used to generate images on a display panel according to one embodiment of the present invention. In the present embodiment, the same composite video signal for the LCD panel is used to create the drive signals needed by the LEDBK. The LCD panel control circuitry may take advantage of the variable light output levels and colors of the LEDBK to improve observed contrast, color brightness, and still reduce overall backlight power consumption.
[0043] FIG. 9 shows a block diagram of a decoder circuit 300 that is used to create the signals shown in FIG. 6 . An Xn scan converter 302 creates the row timing signals that correspond to the image displayed on the LCD panel, so that the brightness and color information needed by the LCD is matched to the correct LED cluster. Red, Green, and Blue video-in signals are provided to the Xn scan converter 302 . The red video-in signal is provided to a processor 304 that outputs current to Red LEDs. The green video-in signal is provided to a processor 306 that outputs current to Green LEDs. The blue video-in signal is provided to a processor 308 that outputs current to Blue LEDs. The variable current outputs of the respective red, green, or blue LED columns provide not just the brightness but the color perceived by the viewer. In the simplest implementation, a one-to-one correspondence between the LED backlight to the LCD panel may exist. In a more cost effective solution, it can be shown that the number of LED clusters can be reduced for a given number of LCD pixels by as much as 10 by using the fact that the human eye has approximately 10 times more rods, which are sensitive to light, than cones, which are sensitive to color.
[0044] The present invention has been described in terms of specific embodiments. As will be understood by those skilled in the art, the embodiments described above may be modified or altered without departing from the scope of the present invention. | pa A display device includes a display panel; and a backlight panel provided below the display panel and defining a plurality of regions. A first array of light emitting diodes (LEDs) is provided along a first direction, each LED of the first array being coupled to a first line. A driver is coupled to the first line to drive the LEDs coupled to the first line. A second array of LEDs is provided along a second direction, each LEDs of the second array being coupled to a second line. A lighting condition of the regions defined by the backlight panel is controlled by turning on or off the LEDs. | 6 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] A building block can be made of a polymer and includes alinement ridges and channels for stack formation, sealant channels, for non-binding sealant, a cavity that can be reinforced, for studs or wood used as supports or spacers for insulation or supporting dry wall, and central passageways, for routing pipes, wires, etc., decorative surfaces, and easy grip ribs.
[0003] 2. Description of Related Art
[0004] The present application is a modification and/or improvement over your applicant's similar prior published U.S. patent application No. 2004/0221538 filed 28 Apr. 2003. J. Lee (U.S. Pat. No. 541,815, issued 25 Jun. 1895) and H. Palmer (U.S. Pat. No. 674,874, issued 28 May 1901) and J. Miller (U.S. Pat. No. 800,385, issued 26 Sep. 1905) and R. Wilkinson (U.S. Pat. No. 4,573,301, issued 4 Mar. 1986) are examples of building blocks having recesses or openings for reception of building elements. C. Cahill (U.S. Pat. No. 1,950,397, issued 13 Mar. 1934) and L. Baylor (U.S. Pat. No. 2,539,177, issued 23 Jan. 1951) are examples of building blocks provided with reinforcement. R. Dula (U.S. Pat. No. 1,411,005, issued 28 Mar. 1922) and J. Linn (U.S. Pat. No. 1,780,086, issued 28 Oct. 1930) and D. Loftus (U.S. Pat. No. 1,925,103, issued 5 Sep. 1933) and Ozawa et al (U.S. Pat. No. 2001/0023559 published 27 Sep. 2001) are examples of building blocks provided with facings. J. Linn and D. Jensen (U.S. Pat. No. 5,457,926 issued 17 Oct. 1995) and Barton Jr. et al (U.S. Pat. No. 5,826,394, issued 27 Oct. 1998) are examples of building blocks having tapered ribs. Jensen et al (U.S. Pat. No. 4,193,241, issued 18 Mar. 1980) teaches a masonry block filled with insulation having a cavity to expose the “central divider” so that the block can be gripped and picked up.
SUMMARY OF THE INVENTION
[0005] A waterproof building block is formed by molding a composite polymer concrete so as to have horizontal ridges or tongues and channels or grooves on the upper and lower surfaces. Internal vertical openings provide for passage of pipes, wires, HVAC tubes, etc. A central cavity is provided in one side of the block and extends into the block central rib or end walls. A vertical central rib can be provided with a protective metal or other material insert for reception of a removable stud or a wooden block that can be used to form a spacing for support insulation and/or dry wall attachment. A composite polymer concrete can be composed of a fiber reinforced polymer composite material using a resin binder, aggregate and possible fillers formed with easy grip ribs and decorative surfaces.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] FIG. 1 is a perspective view of a building block of the invention showing the top with a wood stud inserted.
[0007] FIG. 2 is a perspective view of a building block of the invention showing the bottom.
[0008] FIG. 3 is a perspective exploded view of the building block of FIG. 1 with a section broken away and optional insert.
[0009] FIG. 4 is a perspective view of a first modification of the building block shown in FIG. 1 .
[0010] FIG. 5 is a perspective view of a second modification of the building block shown in FIG. 1 .
[0011] FIG. 6 is a prospective view of a third modification of the building block shown in FIG. 1
[0012] FIG. 7 is a perspective view of a fourth modification of the building block shown in FIG. 1 .
[0013] FIG. 8 is a top view of the building block of FIGS. 1-3 .
[0014] FIG. 9 is a cross-sectional view of a central rib with a cavity as shown by the section line 9 - 9 of FIG. 9 .
[0015] FIG. 10 is a broken out section of one embodiment of a block front face
[0016] FIG. 11 is a broken out section of another embodiment of a block front face.
[0017] FIG. 12 is a perspective view of a wall section constructed with the building blocks of FIG. 1 .
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0018] An interlocking building block 1 , shown in FIGS. 1-3 , is provided that can be manufactured from standard construction materials such as cement, sand or other fine aggregate, and coarse aggregate of less than ¾″. The block 1 is composed of a finished front wall 11 , finished end walls 12 , and an unfinished back wall 13 , and a central rib 14 . The central rib 14 contains a central cavity 2 , into which a wooden 20 or other stud 24 can be inserted for fabricating a wooden support system.
[0019] The blocks can be colored and formed with decorative coverings on their front 11 and end walls 12 that resemble brick, stucco, siding, etc. The blocks are strong enough to be competitive with conventional concrete blocks. The blocks contain horizontal ridges 16 , on their upper surface 18 , which are designed to mate with formed channels 17 on the lower surfaces of adjoining blocks. The channels and ridges comprise a tongue-and-groove system, which serves two purposes: (1) to align one block's top surface with another block's bottom surface, and (2) to receive a non-binding sealant that will waterproof the joint of the block. Because the sealant is non-binding, the blocks can be easily disassembled and then recycled. The horizontal ridge 16 extends along the front and the ends of the upper surface 18 . The channels and ridges provide the means for both rapid assembly and disassembly. They also allow easy alignment of blocks over each other. The outer walls of the block 11 , 12 , 13 and the interior rib shown as a central rib 14 define vertical apertures or openings 19 . When the blocks are in alignment, communication is provided between the openings in the blocks that are then vertically aligned with each other. This vertical alignment of the openings 19 provides a passage for various utilities, such as electrical conduit, HVAC, or piping. A vertically elongated central recess, or central cavity 2 , is made through the unfinished back side 13 and into the wider central rib 14 . Obviously, the cavity is narrower than the central rib 14 , and extends into the central rib without communicating with the vertical openings, or open passages 19 . The inner surfaces of the cavity 2 are spaced appropriately from both the upper and lower surfaces in order to provide support and strength for wooden or other studs 20 , 24 that can be inserted into the cavity.
[0020] A metallic insert 21 can be inserted into the inner surfaces of the cavity 2 as shown in FIG. 3 . This metal insert is attached or bonded to the block material lining the cavity by a binder or interlocking spikes 22 . The metal insert 21 is designed to distribute forces imposed by studs 20 to the building block sides and central rib material so that wear and tear on that material, due to localized forces, is reduced. The interlocking spikes 22 are formed by punching them out from the metallic insert 21 . Also, there are removable stud mounting holes 23 formed in the insert. The metallic insert 21 , equipped with the spikes 22 and mounting holes 23 , receives wooden or other studs 20 . The wooden stud has an end surface into or onto which fasteners can be attached for the purpose of hanging drywall. A non-wooden stud 24 is a removable plastic or metal preformed stud insert. It is in the shape of a “U”, and possesses a base 26 with legs 25 extending out from the base 26 . Furthermore, the legs of the removable non-wooden stud are provided with protrusions 28 . The removable studs 24 are held in the metallic insert 21 by means of the protrusions 28 being inserted into the stud mounting holes 23 . A slightly different means is used to retain the wooden studs 20 in the metallic insert 21 . The wooden stud is glued to the insert with some sort of binder or it is impaled by the interlocking spikes 22 . The length of the wooden studs can be chosen so as to give the builder the choice of any desired spacing between the block and drywall, or any other finishing material attached to the outer ends of the wooden studs 20 or the outer ends of the removable stud inserts 24 and the blocks rear surfaces. The wooden studs 20 provide a space between the back side 13 of the studs and the unfinished block back side. This space can be used to position insulation between the blocks and a drywall attached to the stud ends.
[0021] The first modified block 40 shown in FIG. 4 is similar to that in FIG. 1 , except that the cavity 42 is in the wider end wall 46 as opposed to being located in an interior or central rib. The same front wall 11 , end walls 12 , horizontal ridges 16 and grooves 17 and open passages 19 are retained. The unfinished back wall 43 accommodates the cavity 42 with a thinner central rib 44 and easy grip 45 .
[0022] The further modified block 50 shown in FIG. 5 is similar to that shown in FIG. 4 , except that there are two cavities 51 , 52 placed in wide end walls 56 , 57 respectively . The cavities 51 , 52 are formed in the unfinished back wall 53 . The same front wall 11 , end walls 12 , horizontal ridges 16 and grooves 17 , and open passages 19 are retained. The unfinished back wall 53 accommodates the two end cavities 51 , 52 with a thin central rib 54 and easy grip 55 . The studs are housed within the cavities 51 , 52 .
[0023] In FIGS. 4 and 5 , the intermediate ribs 44 and 54 , respectively, are relatively thin as there is no need to accommodate an insertion of any type. In view of this, the easy grips 45 , 55 on the central rib tops are wider than that of the central rib upper areas but are much narrower than that shown in FIG. 1 , yet they still serve as easy grips for control of the blocks.
[0024] The block 60 shown in FIG. 6 is similar to that in FIG. 5 , except that it is provided with two wide internal ribs 64 , 65 , and three vertical open passages 19 . The wide central ribs each house cavities 61 , 62 formed in the unfinished back wall 63 . The block 60 has the same front wall 11 , end walls 12 , and horizontal ridges and grooves 16 , 17 . The wide internal ribs surround the cavities to secure the studs in place. The tops of the internal ribs are provided with easy grips 66 , 67 .
[0025] The block 70 shown in FIG. 7 has the same front wall 11 , end walls 12 , back wall 73 and horizontal ridges and grooves. The central rib section of the block 70 has a wide rib upper surface 74 with easy grip 75 . The rib can expand from the front to the back or can be provided with a wide section 71 having a horizontal elongated width for receiving a stud in a cavity 72 in the back wall 73 . The cavity 73 in the back wall can be made at any desired angle with the back wall into the wide section 71 .
[0026] FIG. 8 is a top view of the block of FIGS. 1 and 2 and FIG. 9 is a cross-sectional view of an intermediate rib along the section lines 9 - 9 of FIG. 8 . The central rib 14 grip 5 is formed with a wider central rib top 6 than central rib upper 3 so that a worker can easily grab and move the block. The central rib has a cavity 2 between the central rib upper 3 and the central rib base 4 that accommodates a wood stud 20 or other insert. A pin hole 27 extends between the cavity 2 and a vertical opening 19 so that a securing pin or screw can be inserted from the vertical opening 19 into the cavity 2 to secure a wooden stud, for example, into the cavity.
[0027] FIGS. 10 and 11 show sections of the front faces 11 of blocks. The face 11 in FIG. 9 is formed by molding into the block thin brick sections 91 that give the appearance of a brick wall. The face 11 of FIG. 10 is formed by molding into the block a coating of brick powder 92 in any preferred decorative form.
[0028] FIG. 12 displays building blocks assembled together to form a three-tiered wall. The bottom and top tiers show wooden studs 20 inserted into the central cavities 2 on the unfinished face 13 of the blocks 1 . In conjunction with the tongue-and-groove system 16 , 17 , there is also provided, for further securing of the wall in place, tie-down bolts 93 that passes through plates 94 and open passages 19 in the blocks.
[0029] It is believed that the construction, operation and advantages of this invention will be apparent to those skilled in the art. It is to be understood that the present disclosure is illustrative only and that changes, variations, substitutions, modifications and equivalents will be readily apparent to one skilled in the art and that such may be made without departing from the spirit of the invention as defined by the following claims. | Molded composite polymer construction blocks are made that are easily assembled, using tongues and grooves, with vertical passageways for pipes, wires, etc. Stud supporting cavities in one side of the block extend into the ribs or end walls. The cavities can be provided with protective inserts. Studs or wooden blocks can be inserted into the cavities. The wooden studs or wooden blocks of various lengths provide spacing for insulation and/or drywall installation. Internal ribs are provided with easy grip structure. One, two or three side walls of the block are provided with decorative surfaces. | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional Patent Application No. 61/084,344, filed Jul. 29, 2008. The entire disclosure of the above application is incorporated herein by reference.
GOVERNMENT INTEREST
[0002] This invention was made with government support under Grant No. EEC9986866 awarded by the National Science Foundation. The government has certain rights in the invention
FIELD
[0003] The present disclosure relates to microsystems and, more particularly, relates to methods for compact multilevel electrical integration of microsystems.
BACKGROUND
[0004] The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
[0005] Many applications in neuroscience and neural prosthetics would benefit from having three-dimensional arrays of electrodes to allow the simultaneous monitoring of interactions among networks of neurons spanning multiple layers of brain. However, creating practical three-dimensional arrays has remained a challenge. Typically, neural probes are batch fabricated using planar processing techniques, resulting in two-dimensional electrode configurations which have to be micro-assembled to form 3-D arrays. The existing assembly approaches are tedious and result in fragile and oversized devices. The present teachings present a novel approach to 3-D microelectrode array formation and wire overlay that enables easy high-yield assembly and pushes the limits of miniaturization.
[0006] Several approaches exist for electrically interfacing with neurons in a volume of tissue. The earliest, cheapest and most widely available method involves microwire arrays which are typically bundled together with tips staggered at different heights. A silicon-based alternative to the microwire solution was developed at the University of Utah. Although the physical structure of these arrays appears three-dimensional, neither can be considered true 3-D electrical interfaces because they lack multiple channels that simultaneously span the longitudinal, transverse and vertical dimensions. Two-dimensional arrays fabricated back-to-back that fold into 3-D arrays have also been demonstrated, but these are inherently limited to only two parallel sets of shanks.
[0007] True 3-D interfaces formed by assembling 2-D arrays in parallel have been demonstrated in the past. However, the assembly methods developed thus far are tedious, preventing the 3-D arrays from being supplied in quantity. The past approaches to assembling two-dimensional probes (passive or active) involve inserting the individual shanks 102 on each probe into corresponding holes formed in a thin silicon platform 104 and securing the multiple probes in parallel with orthogonally-fitted comb-like structures, called spacers, as shown in FIGS. 1( a )-( c ) and 2 ( a )-( b ). In this assembly process, the first step is to orthogonally bend the gold tabs on each probe wing such that they are parallel to the platform surface. In this state, the probe backend is held by a vacuum pick that is connected to a 3-way micromanipulator. Then the shanks are orthogonally aligned to the holes in the platform and dropped into the platform. This process is repeated for each probe making up the 3-D array. Next, the silicon spacer 106 is fitted and used to stabilize all probes, which otherwise would wobble due to the weight of the protruding backend 108 . Finally with the probes in place and stabilized on the platform, the gold tabs on each probe wing 110 are ultrasonically bonded to the platform. A picture of an assembled 3-D array using four parallel active probes orthogonally assembled on a silicon platform and stabilized by silicon spacers 106 is shown in FIGS. 2( a )-( c ).
[0008] This approach has a number of disadvantages. The 2-D arrays used for 3-D assembly are specifically designed with lateral wings that take significant space, not only from the device point of view but also on the mask. The thin silicon platform (˜15 μm), defined by a boron etch-stop process, must carry the assembled probes and perhaps other integrated circuit components, and while it is supported on a solid metal block during assembly, it is fragile and difficult to use for multiple implants. The idea of individual holes in the platform for each shank has merit for encapsulation around each shank as was demonstrated with a glass frit reflow process, but results in a tedious assembly procedure since each shank must be precisely aligned before the entire probe can be inserted. Once all probes are inserted into the platform, they must be manually held in parallel relation while the spacer is being aligned and fitted. This is yet another tedious and time consuming step. In bonding the lead tabs, the bond wedge (typically 100 μm at the tip, tapering at 15°) must be able to access tabs in between the wings, limiting the array spacing. The bond wedge must also access the inner-most tab on each wing without interfering with the backend, which results in “dead” space on the wing that places the inner-most tab a minimum distance away from the backend of the probe. A substantial vertical rise of the array above the platform cannot be avoided even with passive probes since vertical spacers are used for stabilization. This is a major limitation, especially with active probes, that complicates or even prohibits the post-implant procedure of replacing the dura over the device. Although a folding backend technology was developed, the vertical rise is still of concern since multiple backends are stacked on top of each other. Furthermore, the folding technique is not effortless. The successful assembly of just one 3-D array using the described approach can take an hour or more. Even then, these structures remain relatively large and fragile for fully implantable applications.
SUMMARY
[0009] According to the principles of the present disclosure, a microsystem is provided comprising a substrate having an aperture formed therethrough. The aperture includes a first cross-section and a second cross-section—the first cross-section being smaller than the second cross-section to define a ledge therebetween. A probe member is disposed within the aperture of the substrate, such that a backend of the probe member defines a cross-section that is greater than the first cross-section of the aperture and smaller than the second cross-section such that the probe member engages the ledge. A plurality of probe shanks extend from the probe member. Each of the probe shanks includes a plurality of leads disposed therealong, each of the leads extending from the probe shanks to an opposing side of the probe member.
[0010] Further areas of applicability will become apparent from the description provided herein. It should be understood that the description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.
DRAWINGS
[0011] The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way.
[0012] FIG. 1( a ) illustrates an active probe designed for 3D assembly includes lateral wings and spacer slots on the backend according to the prior art;
[0013] FIG. 1( b ) illustrates an etch-stop defined silicon platform designed for assembly having individual holes for shanks and routing lines;
[0014] FIG. 2 illustrates an assembled 3D array using four parallel active probes orthogonally assembled on a silicon platform and stabilized with silicon spacers;
[0015] FIG. 3( a ) illustrates a top view of a 3D array of neural microelectrodes according to the present disclosure;
[0016] FIG. 3( b ) illustrates a cross-sectional view of the 3D array of neural microelectrodes according to the present disclosure taken along lines 3 - 3 of FIG. 3( a );
[0017] FIG. 3( c ) illustrates a top perspective view of the 3D array of neural microelectrodes according to the present disclosure;
[0018] FIG. 3( d ) illustrates a bottom perspective view of the 3D array of neural microelectrodes according to the present disclosure;
[0019] FIG. 4 is a series of views illustrating various slot design configurations for zero rise 3D neural probe arrays;
[0020] FIG. 5 illustrates a cross-sectional view of the 3D array of neural microelectrodes according to the present disclosure;
[0021] FIG. 6( a ) illustrates a silicon neural probe design;
[0022] FIG. 6( b ) illustrates an enlarged view of the silicon neural probe design of FIG. 6( a );
[0023] FIG. 6( c ) illustrates a high-density silicon neural probe design;
[0024] FIG. 6( d ) illustrates an enlarged view of the high-density silicon neural probe design of FIG. 6( c );
[0025] FIG. 7( a ) illustrates a platform design for a compact 3D neural probe array;
[0026] FIG. 7( b ) illustrates an enlarged view of the compact 3D neural probe array of FIG. 7( a );
[0027] FIG. 7( c ) illustrates a high-density compact 3D neural probe array;
[0028] FIG. 7( d ) illustrates an enlarged view of the high-density compact 3D neural probe array of FIG. 7( c );
[0029] FIGS. 8( a ) and 8 ( b ) illustrate optical profilometer graphs showing the simultaneous etching of the slots and perimeter in the fabrication of the compact 3D array platform;
[0030] FIG. 9 illustrates an SEM picture showing the cross-sectional profile of slots etched 300 μm deep;
[0031] FIG. 10 illustrates an SEM picture showing the cross-section of DRIE etched slots in the case where the slot and perimeter openings are equal;
[0032] FIG. 11( a ) illustrates a silicon assembly carrier;
[0033] FIG. 11( b ) illustrates a metal support block for use with the silicon assembly carrier;
[0034] FIG. 11( c ) illustrates the assembly jig employing the silicon assembly carrier and meal support block;
[0035] FIG. 12( a ) is an SEM picture showing the fabricated probe used for the assembly of the zero-rise 3D array;
[0036] FIG. 12( b ) is an enlarged SEM picture from FIG. 12( a );
[0037] FIG. 13( a ) is an SEM picture showing the fabricated probe used for the characterization of high density tab bonding;
[0038] FIG. 13( b ) is an enlarged SEM picture from FIG. 13( a );
[0039] FIG. 14( a ) is an SEM picture showing the tip of the tab bonding tool having a 25 μm tip diameter;
[0040] FIG. 14( b ) is an SEM picture showing the tip of the tab bonding tool having a 55 μm tip diameter with raised plus;
[0041] FIG. 14( c ) is an SEM picture showing the tip of the tab bonding tool having a 60 μm square tip with raised plus;
[0042] FIG. 15( a ) is an SEM picture showing the assembled and bonded probe with 25 μm wide tab (40 μm pitch);
[0043] FIGS. 15( b )-( c ) are SEM pictures showing the assembled and bonded probe with 25 μm wide tab (40 μm pitch);
[0044] FIG. 16 is an SEM picture showing the assembled and bonded probe with 10 μm wide tab (15 μm pitch);
[0045] FIGS. 17 and 18( a )-( c ) illustrate the zero-rise 3D array on a US penny or human finger;
[0046] FIG. 19( a ) illustrates a cross-sectional view of traditional microsystems on a platform having components physically mounted on the platform with electrical wire bond connections,
[0047] FIG. 19( b ) illustrates a cross-sectional view of traditional microsystems on a platform having components recessed into a cavity with electrical wire bond connections
[0048] FIG. 19( c ) illustrates a cross-sectional view of traditional microsystems on a platform having components wherein the electrical connections use wire bonding from component pads to platform pads and routing lines patterned on the platform between components;
[0049] FIGS. 20( a )-( c ) illustrate a series of views of traditional 64-channel integrated wireless microsystem on a silicon platform called SPIDER (Subcutaneous Programmable Interface Device for Extracellular Recording) measuring 1.4 cm×1.54 cm;
[0050] FIG. 21 illustrates a fully-implantable neural prosthetic microsystem;
[0051] FIG. 22( a ) illustrates a cross-sectional view of the overlay cable according to the present disclosure;
[0052] FIG. 22( b ) illustrates a top view of the overlay cable according to the present disclosure;
[0053] FIG. 22( c ) illustrates a side view of the microsystem integration method using the overlay cable according to the present disclosure;
[0054] FIG. 22( d ) illustrates an enlarged top view of the tab portion of the overlay cable according to the present disclosure;
[0055] FIGS. 23( a )-( d ) is a series of views illustrating the microsystem integration using overlay cable approach, beginning with a platform with multiple components ( FIG. 23( a )) and an overlay cable design ( FIG. 23( b )), overlaying the cable overlay onto the platform and aligning and ultrasonically bonded to components on the platform ( FIG. 23( c )), with an enlarged view of the metal tab of the overlay cable bonded to the pad on the component ( FIG. 23( d ));
[0056] FIG. 24 illustrates an overlay cable that can be wrapped around the platform for the double-sided integration of components;
[0057] FIG. 25( a ) illustrates an SEM image of the parylene overlay cable;
[0058] FIG. 25( b ) illustrates an SEM image of the tab and interconnect regions of the overlay cable;
[0059] FIG. 25( c ) illustrates an SEM image of the tab and interconnect regions of the overlay cable;
[0060] FIG. 26( a ) illustrates an SEM image of the front side probe array tabs and cutout regions in the overlay cable;
[0061] FIG. 26( b ) illustrates an SEM image of the back side probe array tabs and cutout regions in the overlay cable;
[0062] FIG. 26( c ) illustrates an SEM image of the front side circuit bonding tabs and cutout regions in the overlay cable;
[0063] FIG. 26( d ) illustrates an SEM image of the back side circuit bonding tabs and cutout regions in the overlay cable;
[0064] FIGS. 27( a )-( b ) illustrate photographs of the cable designed to connect the 3D array with the front-end signal conditioning chip;
[0065] FIGS. 28( a )-( b ) illustrate photographs of the fabricated parylene overlay cable on a US penny;
[0066] FIG. 29 illustrates a neural recording microsystem front-end integrated using the compact 3D array and overlay cable approach of the present disclosure;
[0067] FIG. 30( a ) illustrates a top view of a cavity formed in a platform;
[0068] FIG. 30( b ) illustrates a cross-sectional view of the cavity of FIG. 30( a ) taken along Line 30 - 30 ;
[0069] FIG. 30( c ) illustrates a top view of a signal conditioning chip disposed in the cavity of the platform;
[0070] FIG. 31( a ) illustrates a diagrammatic view of a probe tab bonding to platform pads;
[0071] FIG. 31( b ) illustrates a diagrammatic view of a cable overlay with tab bonding to platform;
[0072] FIGS. 32( a )-( h ) illustrate a series of photographs of tab bonding employing the present disclosure having a probe array with 25 μm wide tabs, a chip with 100 μm wide tabs and patterned interconnect lines being 10 μm wide; and
[0073] FIG. 33 illustrates an integrated microsystem using the parylene overlay cable approach of the present disclosure.
DETAILED DESCRIPTION
[0074] The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses.
The Compact 3D Array: Concept and Design Considerations
[0075] A new high-yield compact approach to 3-D microelectrode array formation is described here along with its design considerations according to principles of the present teachings. In the present architecture, shown in at least FIGS. 3( a )-( c ), a microsystem 2 is provided wherein the 2-D probes 10 (passive or active) are designed to eliminate the undesirable wide-span lateral wings used in the past, resulting in a more generic design that also saves layout area on the mask. Extending off the backend 12 of this 2-D probe design are bendable electroplated gold tabs 14 for lead transfer. The platform design relies on a thicker silicon substrate 16 , rather than the thin boron diffused structure used in the past, to countersink the probe backend 12 into slots 18 formed in the silicon. As shown in FIG. 3 , the platform slot is used to countersink the backend 12 of the 2-D probe 10 and hold it on an internal ledge 20 while the shanks 22 penetrate through the silicon substrate 16 .
[0076] The present architecture allows for a high degree of flexibility and control of design parameters. For any given geometric configuration of recording sites (as required by an application), the appropriate 2-D probes can be designed and then the platform can be designed to fit the probes at the appropriate spacing. As a key advantage, this architecture allows to further push the limits of device compactness. Consider the length and width of a slot in the platform. A single slot actually consists of a top-side slot, which countersinks the backend and creates a supporting ledge, and a back-side slot, which creates a through hole 24 for the shanks 22 together with the top-side slot 18 (refer to FIG. 3( b )). In this platform design, a single slot is preferred rather than perforated holes for each shank to simplify fabrication and assembly.
[0077] Referring to FIG. 4 , the minimum back-side slot length, dimension A, is determined by the number of shanks, their width and pitch. For example, a 2-D array consisting of 4 shanks, each 50 μm wide separated by 150 μm, would span a total distance of 650 μm representative of a typical 2-D silicon neural recording array. Therefore, the minimum back-side slot length, dimension A in FIG. 4 , would be 650 μm, not including any assembly tolerances. The minimum top-side slot length and the length of the probe backend, dimension B in FIG. 4 , determine the overall size of the array and limited in minimum size by the span of the shanks. In this assembly approach, the backend of the probe must overhang the span of the shanks (dimension C in FIG. 4 ) to create wings that sit on a support ledge created in the platform. However, unlike the previous approach to wings which carried electrical leads and spanned hundreds of microns, here the wings are used purely for physical support, so this dimension is only on the order of tens of microns. It should be appreciated that the wings could be eliminated depending on the specific application and use.
[0078] The slot width is determined by the thickness of the probe. For passive probes, the thickness of the backend and shanks will differ only by a few microns where the difference is determined by the thickness of the gold electro-plated tabs. For active probes, the thickness of the backend is approximately 3 times larger (˜50 μm) compared to the shank thickness (˜12-15 μm). The typical backend and shank thicknesses for the University of Michigan passive and active silicon probes are detailed in Table 1. The minimum top-side slot width, dimension D in FIG. 4 , is determined by the total thickness of the backend of the probe, while the minimum back-side slot width, dimension E in FIG. 4 , is determined by the thickness of the shanks. Since the probe is countersunk into the platform from the top-side, a natural stabilization mechanism is created but due to finite assembly tolerances, this dimension also determines the tipping angle of the shanks. For example, a 5 μm assembly tolerance in the top-side slot would result in a 1° tipping angle of the shanks when the backend is placed in a 300 μm deep slot. The back-side slot primarily creates a through hole for the shanks and is not critical in stabilizing the probe. For passive probes it is acceptable for the top- and back-side slot widths to be equal but in practice (during fabrication) there will be a mismatch due to mask alignment tolerances on the order of 1 μm. Therefore, it is preferred that the back-side slot be wider than the top-side slot so that in the case of misalignment no obstruction is created in the through hole, making the assembly easier. In the case of 3-D arrays using active probes, slot width and alignment should be designed appropriately such that the back-side slot is offset from the top-side slot to achieve the best stabilization mechanism.
[0000]
TABLE 1
Shank and backend thicknesses for passive and active probes.
Passive Probe
Active Probe
A.
Silicon backend
12 μm
50 μm
B.
Silicon shank
12 μm
12 μm
C.
Lower dielectric stack
0.9 μm
0.9 μm
Pad oxide (thermal)
1500 {acute over (Å)}
LPCVD oxide
3000 {acute over (Å)}
LPCVD nitride
1500 {acute over (Å)}
LPCVD oxide
3000 {acute over (Å)}
D.
Polysilicon
0.6 μm
0.6 μm
E.
Upper dielectric stack
0.9 μm
0.9 μm
Pad oxide (thermal)
1500 {acute over (Å)}
LPCVD oxide
3000 {acute over (Å)}
LPCVD nitride
1500 {acute over (Å)}
LPCVD oxide
3000 {acute over (Å)}
F.
Site metallization
0.35 μm
0.35 μm
Titanium (Ti)
500 {acute over (Å)}
Iridium (Ir)
3000 {acute over (Å)}
G.
Bond pad metallization
0.55 μm
0.55 μm
Chromium (Cr)
500 {acute over (Å)}
Gold (Au)
5000 {acute over (Å)}
H.
LTO passivation
—
1 μm
I.
Gold shield
—
0.5 μm
J.
Gold plated beam lead tabs
5 μm
5 μm
Shank thickness:
B + C + D +
B + C + D +
E + F = 14.75 μm
E + F =
14.75 μm
Backend thickness:
A + C + D + E +
A + C + D +
G + J = 19.95 μm
E + G + H +
I + J =
59.45 μm
[0079] The spacing between slots, dimension F in FIG. 4 , is determined by the array pitch (dimension G). Typically, shanks are spaced 100-200 μm apart depending on the cell sizes in the specific region of interest to allow the array to record from virtually all neurons in a given area. This dimension determines the maximum length of the bond tabs on the probe while the thickness of the tabs is a fabrication process parameter (typically 3-5 μm thick) which determines the bending strength. The maximum tab length, dimension F in FIG. 4 , is the difference between the array pitch (dimension G) and the top-side slot width (dimension D). The maximum width and pitch of each tab on the probe is determined by the number of sites and the total length of the probe backend. Consider a 16 site 2-D array with 4 shanks spanning 650 μm. If the extension of the backend is 50 μm on each side resulting in a total span of 750 μm for the backend, the tab pitch would be approximately 45 μm. Since these tabs are intended to be ultrasonically bonded to pads on the platform and therefore do not have the same minimum size requirements as would wire-bonded tabs, the maximum width of each tab is determined by the minimum gap between two tabs which is only limited by the fabrication tolerance to avoid electrical shorting. In fact, tab bonding allows for much smaller and tighter tab designs compared to wire bonding, so it is not necessary to utilize the full span of the backend for the tab design. This allows the tab size and pitch to be optimized depending on bonding and/or interface requirements. A design with narrow closely-spaced tabs could facilitate the assembly process by allowing a single ultrasonic bond simultaneously across all tabs. Also, in this 3-D array formation, routing lines on the platform are not considered to be a limitation on the minimum spacing between slots (dimension F) because a planar array of bond tabs is created which opens several options for microsystem integration not previously possible. One such approach is to use flip-chip bonding technology, as is, in fact, being developed for the Utah microelectrode array. The approach taken in the present work uses an overlay film carrying the interconnect lines directly on top of the array and bond pads as will be discussed herein.
[0080] Consider now the thickness of the platform. A standard silicon wafer, which measures approximately 500 μm in thickness, is convenient for processing and results in a corresponding 500 μm of vertical rise above the cortical surface when the array is implanted. Thinner platforms could be considered for the design, to be determined from the trade-off between vertical rise and mechanical robustness. In the present work, the standard silicon wafer thickness was used for the platform design because it is not only strong enough to handle during bonding and implantation but is also compatible with countersinking integrated circuit chips, creating a robust package for a microsystem containing the 3-D array integrated with electronics. The top-side and back-side slot depths, dimensions H and I in FIG. 5 , are determined by the height of the backend of the probe such that it sits flush with the top surface of the platform when inserted. For passive probes, the minimum height of the backend is limited by the fan out of the leads connecting the sites to the tabs. In 3 μm technology, a passive probe having 16 sites would require a minimum H of approximately 50 μm for the lead fan out at the backend (eight 6 μm pitch lines). Adding some overlap of the tabs onto the backend, this passive probe could be realistically designed having a backend height of about 75 μm, which would also be the depth of the top-side slot (dimension H), leaving 425 μm for the backside slot depth (dimension I). Active probes with circuitry integrated on the backend typically have much taller backends, depending on the complexity of the circuitry. For example, a multiplexed (64:8) recording probe with 8 amplifiers measures approximately 2.5 mm tall when fabricated in the 3 μm active probe process. In some embodiments, the backend of active probes is limited to the thickness of the platform by including only the site selection circuitry, and that the remaining signal conditioning circuitry is designed as an ASIC that would be integrated into the platform as shown in FIG. 5 . Alternatively, a “hybrid” active probe could be created by designing a chip that makes use of the smaller-feature technologies available at foundries and mounting this chip to the backend of a passive probe, as in the case of the hybrid flip-chip bonded cochlear array. These “hybrid” active depth probes could then be assembled into a 3-D array with the appropriately designed platform.
[0081] In this work, two 16 channel (4 sites per shank) probe designs are considered. The difference is only in the bond tab design at the backend. The first design is a typical probe where the tab width is maximized to utilize the entire span of the backend. In the second design, a smaller tab with tighter pitch is investigated to explore bonding feasibility. The high-density tab design can provide useful information for future designs of probes that include more sites or channels (in the case of active probes requiring power and control lines) in a limited space. These two probe designs are shown in FIGS. 6( a )-( d ) along with the overall dimensions. In both designs, four shanks span 540 μm. Each shank is 60 μm wide (including boron diffusion), leaving a 100 μm gap between shanks. With a 50 μm ledge on each side, the total width of the backend is 650 μm. Note that as shown in the detail of FIG. 6 , this 650 μm width includes boron lateral diffusion (typically 55% of the diffusion depth for wide mask openings) and a dielectric overlap to prevent leads shorting to the platform. The probe with the larger tab design is shown in FIG. 6( a ) and has 16 tabs spaced at a 40 μm pitch, each tab being 25 μm in width. The probe with a high-density tab design also includes 16 tabs but has a 15 μm pitch with 10 μm wide tabs as shown in FIG. 6( c ). In fact, at this pitch, approximately 42 tabs can be accommodated given the span of the backend on this typical four shank probe although only 16 have been included here for testing the bonding feasibility. The corresponding platform designs for these probes are shown in FIG. 7 . The top-side slot width is designed to be 25 μm based on both the typical probe fabrication process given in Table 1 and includes assembly tolerances. The back-side slot width is made wider than the top side slot by an alignment tolerance of 1 μm resulting in a slot width of 27 μm. In designing the top side slot length, a 25 μm assembly tolerance was used on each side, so that the total top side slot length is 700 μm. The top-side slot depth and the height of the passive probe backend in this work was chosen to be 300 μm leaving about 200 μm for the back-side slot depth need to create a through hole for the shanks. Although the backend could have been designed much smaller, a taller backend was designed to demonstrate the feasibility of deep slots as would be required by active probes. The platform extends the slots by 150μm on all sides to facilitate assembly and handling, resulting in a 1 mm2 device. These platforms are designed to hold four probes spaced 200 μm apart, demonstrating a 64-channel array (4×4×4) to interface with neurons in a 1 mm3 volume of tissue.
Fabrication and Assembly
Platform Fabrication
[0082] The fabrication of the passive and active 2-D silicon arrays is a standard process, the details of which can be found elsewhere. The focus here is on the fabrication of the platform. The fabrication of the platform starts with a double-side-polished silicon wafer, approximately 500 μm thick. First, silicon dioxide is grown on the wafer using thermal oxidation at 1100° C. to obtain an oxide thickness of approximately 1.2 μm. Next, the front-side of the wafer is metalized with 200 Å of chromium (Cr) and 5000 Å of gold (Au) and patterned using liftoff to define bond pads on the platform. Continuing processing on the front-side of the wafer, slot openings and the perimeter of the platform are defined in a single lithography step using a thick photoresist (˜15 μm). Anisotropic deep reactive ion etching (DRIE), a combination of silicon etching and pasivation, is used to etch the patterned areas approximately 300 μm deep from the front-side of the wafer. Following this step, the process wafer is mounted to a glass carrier wafer using photoresist. Then the back side of the process wafer is aligned to the front side and patterned to define the back-side slot and perimeter regions. Again, anisotropic DRIE is used to etch the patterned regions to a depth of about 200 μm until the back side etch reaches the front-side etch, creating a through hole in the slot regions and releasing the platform from the bulk wafer in the perimeter. Finally, the process wafer is soaked in acetone to dissolve the photoresist and separate the individual platforms from the carrier wafer. An isopropyl alcohol (IPA) rinse is used to clean any remaining residue from the devices.
[0083] Simultaneous etching of the slots and perimeter, shown in FIG. 8 as captured by an optical profilometer (Zygo), simplifies the fabrication process into just three lithography steps; bond pad patterning, front-side slot/perimeter etch, and back-side slot/perimeter etch and release. The etch rate was characterized for the platform design shown in FIG. 7 using a high-aspect-ratio etch recipe with 130 sccm of SF6 for silicon etching and 85 sccm of C4F8 for the passivation step with a chamber pressure of 94 mT and a platen power of 100 W. It is well known in DRIE etching that the etch rate decreases for deeper structures so the average etch rate is given here. Using the above mentioned recipe, the characterized etch rate for a 300 μm deep slot/perimeter with an opening of 25 μm is approximately 1.6 μm/min. The etch rate is only slightly faster, 1.9 μm/min, for the 200 μm deep back side etch with approximately the same mask opening. In FIG. 9 the profile of slots etched 300 μm deep is shown in an SEM picture. The taper towards the bottom of the slot was calculated to be approximately 2° from measurements taken from this cross-section in the SEM. The key in this process is to ensure that a through hole is created in the slot region before the device is released along the perimeter. This can be achieved by designing the two openings to be equally wide. A cross-section of the etched slots, shown in the SEM picture of FIG. 10 , reveals a cusp that is formed at the point where the back-side slot meets the front-side slot. Although the opening at the meeting point is wide enough to insert the shanks, this cusp can hinder the insertion of shanks if the design tolerance is too tight. This can be overcome by designing the back-side perimeter opening to be slightly smaller (˜5 μm) in width compared to the slot opening. This allows the back-side slot area to be over etched before the perimeter is released, thus creating a smoother through hole in the shank penetration region.
Assembly
[0084] The released platforms, measuring 1 mm×1 mm×0.5 mm must be secured during the assembly procedure, which includes the insertion of 2-D probes into the platform followed by tab bonding to make electrical connections from the probe to the platform. To secure these platforms, an assembly wafer was micromachined using a two-mask DRIE process. In the first step, the outline of the platform is etched approximately 200 μm deep. Then a second DRIE etch from the backside of the wafer was used to produce a single through-hole overlapping all slot regions. The wafer was then diced into approximately 1 cm×1 cm dies of silicon (500 μm thick) containing multiple micro-machined mounting regions, referred here as the silicon assembly carrier. Since the assembly carrier is only 0.5 mm thick, a supporting metal block 5 mm tall was used to clear the shank length (4 mm in this work) during assembly. The silicon carrier is secured to the support block using a silicone elastomer around the edges, creating the assembly jig shown in FIGS. 11( a )-( c ). The 3-D array platform is placed in the carrier wafer and secured by applying a dissolvable lacquer such as nail polish or hand soap along the perimeter of the platform and allowing it to harden in place. Care must be taken to avoid drowning the entire platform in the lacquer and also to prevent the lacquer from encompassing the bond pads on the surface of the platform. Since the silicon carrier is micromachined, multiple platforms can be assembled simultaneously using this setup. Using this jig, a three-way micromanipulator mounted with a vacuum pick, and a stereo-microscope, individual 2-D probes are aligned to the slots in the platform and dropped into place. Following the insertion of all 2-D probes (four probes in this work), a glass micropipette or tweezers can be used to roll over the platform, simultaneously bending all tabs onto the bond pads on the platform. Each array should be positioned in the slot such that the probe sites face toward the bond pads on the platform. This ensures that the tabs, which have a chromium adhesion layer on the back side, are bent over with the gold side down onto the bond pads on the platform. The jig is then moved to a wire bonder to make electrical connections using ultrasonic tab bonding of the gold tabs to the gold bond pads. The entire assembly process from inserting four 2-D arrays to bonding 64 tabs, takes less then half and hour for a single device. In comparison, the previous approach used to assemble a similar-sized array, involving the alignment of individual shanks to corresponding holes and the insertion of spacers took more than 3 hours. Once bonding and electrical continuity tests have been completed, the loaded platform can be soaked in acetone or water, depending on which lacquer was used, for approximately 10 minutes and removed with tweezers from the jig.
[0085] The fabricated probe designs used for assembly in this work are shown in the SEM pictures of FIG. 12 and FIG. 13 along with a close up of the electroplated gold tabs. Custom tab bonding tools, shown in FIG. 16 , were ordered from Gaiser Tool Company with various tip configurations to investigate single- and multi-tab bonding feasibility. One of these has a flat tip with a 25 μm diameter while the other two are larger in size (55 μm and 60 μm) and have a cross ridge pattern at the tip. The patterned tips are thought to be more efficient in the transfer of ultrasonic energy, making a stronger better-quality bond. SEM images of an assembled and bonded probe with 25 μm and 10 μm wide tabs are shown in FIGS. 14 and 15 using the K & S model 4123 bonder with experimentally-determined parameter settings. The wider tabs were ultrasonically bonded using the 25 μm diameter flat tip ( FIG. 14( a )). The high-density tabs were bonded using the larger bonding tools with the square and round tips to demonstrate simultaneous multi-tab bonding. These tools were used to bond two 25 μm wide tabs and four high-density tabs with 15 μm pitch simultaneously, demonstrating the ability to speed up the assembly process. The bond quality depends on three main parameters of the ultrasonic bonder: the force exerted by the wedge, the power of the ultrasonic waves, and the duration of the process. Electrical continuity was verified between the bond pads on the platform and the sites on the probe by dipping the shanks into saline solution connected to an electrode and probing the bond pad on the platform. A photograph of the fully-assembled compact 3-D array with the platform measuring 1 mm×1 mm holding 4 mm-long shanks is shown on a U.S. penny in FIG. 17 . This array has 64 sites using four probes in parallel with each having 4 shanks and provides an electrical interface covering approximately 1 mm3 in tissue. Other highlight views of the array or shown in the photographs of FIG. 18 .
Discussion
[0086] A novel approach to the formation of 3-D arrays of neural electrodes was presented herein. The key advantages of this approach include (1) a low-profile nature that facilitates implantation, (2) alternative options of system integration including flip-chip bonding given the planar surface, (3) compactness, and (4) ease of assembly and robustness. However, the arrays by themselves are limited in use; bonding individual wire connections to the outside world is tedious and inconvenient. At the least, a micro-fabricated cable is necessary but due of the nature of the neural signals, buffering/amplification is critical up-front for transferring uncorrupted data out of the implant. Several options are available for electrically integrating this array with signal conditioning circuitry, including flip-chip bonding of an ASIC onto the array (vertical integration) as done with the Utah array. However this approach results in a stacked structure that ultimately defies the low-profile nature of this architecture. Previous Michigan 3-D arrays used lateral integration with circuit chips placed on the same platform as the 3-D array of probes. However the lateral routing of leads from the probes to the chips consumed significant area on the platform, and was partly a limitation on the minimum size of the array (the other limitation is due to the lead transfers from lateral wings). Even when active probes are used, routing of leads to an integrated silicon cable consumes significant lateral area on the platform. In this work, the footprint of the array is designed to be the minimum size possible (limited by the span of the shanks). With this constraint and taking advantage of the zero-rise, a lateral integration approach that uses a flexible overlay cable is presented herein.
Microsystem Integration
[0087] Neural probes are the fundamental components upon which implantable wireless neural recording/stimulating microsystems are built. In addition to the sensor, Microsystems integrated circuit chips and other hybrid parts such as a coil antenna are needed. The required components must be both physically and electrically integrated to produce a viable microsystem. Typically, a substrate such as a silicon platform is used because it can serve both purposes. Components, such as those referenced at components 130 and 132 ( FIGS. 19( a )-( c )), can be attached to or recessed into the silicon 134 while electrical routing 136 between components can be lithographically patterned on the surface 142 of the platform 134 as shown in FIG. 19( a ) and 19 ( b ). Wire bonding is used to make electrical connections between the pads 138 on the components 130 , 132 and pads 140 on the platform surface 134 , as shown in FIG. 19( c ). The drawbacks of this method include: (1) the surface area required to route the platform interconnections around the components becomes significant as the number of components or the channel-count of the microsystem increases, and (2) wire bonding adds vertical height to the system and requires a finite lateral spacing between two bonding pads (the pitch) and between the component bonding pad and platform bonding pad.
[0088] Consider the 64-channel neural recording microsystem developed prior to this work, which uses the conventional system integration method just described. SPIDER (Subcutaneous Programmable Interface Device for Extracellular Recording) is shown in FIGS. 20( a )-( c ). It includes two 132-channel silicon electrode arrays, four 16-channel front-end integrated circuit chips, two 32-channel signal processing chips, a wireless interface chip, a coil antenna and several surface mount (SMD) capacitors and inductors used for the wireless link. A silicon platform was designed and fabricated to physically assemble and electrically integrate the various components of this microsystem. First, photolithographically-patterned interconnects and bonding pads are defined using a single metal layer (Cr/Au, 200 Å/5000 Å) on an oxidized wafer. To achieve a low vertical profile, component recesses are formed using dry etching (˜300 μm deep) so that each component can be embedded to sit flush with the top surface of the platform. The platform is released from the wafer using two-sided dry etching of silicon along its perimeter. Smooth rounded corners can be formed using a perimeter etch rather than simply dicing the wafer into squares. The fully populated and bonded platform is shown in FIG. 20( a ). As shown in FIG. 20( a ), the neural recording probes are integrated on the platform using a long silicon cable that extends laterally from the platform. The numerous bonding wires can also be seen in FIG. 20( a ). This microsystem measures 1.4 cm×1.54 cm, and weighs 275 mg (populated).
[0089] This integration method is simple and straightforward but has many limitations. First, the probes are separated from the signal conditioning circuitry by long cables (1 cm-2 cm) that are monolithically integrated with the probe backend. In this application where microvolt signals are being transferred from tissue to the microsystem, noise corruption is of significant concern. The signal conditioning circuitry should be as close to the probes as possible. The cable, directly attached to the probe backend as in this method, exerts a tethering force on the probe and may cause it to be displaced from the target region of tissue and/or cause inflammation of the surrounding tissue due to micromotion of the brain in freely moving subjects. Second, for a complex high-channel count system such as this, the platform becomes relatively large due to the number of components, the routing lines, and bonding pads. For the 64-channel neural recording microsystem shown in FIGS. 20( a )-( c ), 48% of the total platform area is consumed by the routing lines, bonding pads, component-to-bonding pad separation and bonding pad pitch. Not only do the routing lines and bonding pads consume significant area on the platform, they also become challenging to place such that there is a one-to-one correspondence between bonding pads of different components. For a complex multi-component microsystem such as this, using a single-metal interconnect level requires wirebond crossovers to form the necessary electrical connections. Criss-crossing wirebonds can results in low yield. A multi-level interconnect process is an option for the platform fabrication but becomes complicated and does not necessarily overcome the problem of area consumption. Furthermore, wirebonds are fragile and have a finite loop height, from as low as 50 μm for the shortest wires to more than 400 μm for the longest wires, adding vertical rise to the microsystem. Third, in this particular application, it is preferred to separate the front-end, where microvolt level analog signals are sensed and processed, from the electromagnetic interference of the wireless link, a challenge not insignificant with the stacked flip-chip approach. Minimizing the size of the front-end also allows for full implantation while the rest of the electronics package can be placed under the skin rather than directly on top of the implantation site as shown in the conceptualization of such an implant in FIG. 21 .
[0090] Clearly, this microsystem, in particular, would benefit from a more compact and robust integration method that also allows for design flexibility. Three dimensional integration techniques using flip-chip bonding or through wafer interconnect technology are a possibility, but some applications especially the neural implants, require very low vertical rise to facilitate the post-surgical procedure of re-sealing the implant opening. This disclosure presents an alternative approach to microsystem integration that allows components to be closely spaced and eliminates the need for wire bonding.
A Compact Zero-Rise Integration Approach
[0091] In the present integration approach, a silicon platform is still used, but serves simply as a physical support for the various microsystem components. Although any rigid substrate can serve this purpose, silicon is still preferred so that lithographically-defined and dry-etched recesses can be easily formed to embed the components flush with the surface of the platform. The electrical connections between components are carried by a flexible overlay cable rather than routing on the platform. A conceptual picture of this integration method using a silicon platform and overlay cable is shown in FIGS. 22( a )-( d ). The cable 30 is in the form of lithographically-patterned lines of metal 32 sandwiched between two layers of any polymer 34 , 36 (ex. polyimide, parylene, SU8) which is compatible with semiconductor manufacturing techniques as conceptualized in FIG. 22( a ). For implantable applications the polymer should also be biocompatible. Each end 38 of the cable 30 has cutouts 40 in the top 34 and bottom 36 polymer layers such that the metal lines 32 terminate as floating tabs 42 as shown in FIGS. 22( b ) and 22 ( d ). The flexible nature of the overlay cable 30 allows it to conform to the surface topology on the component 44 itself or between components 44 , 46 as shown in FIG. 22( c ). The electrical integration of the microsystem is achieved by aligning the overlay cable 30 on top of the components 44 , 46 , which are supported by the platform 48 , and ultrasonically bonding, at 52 , the cable termination tabs 42 to the component bonding pad 50 as shown in FIGS. 23( a )-( d ).
[0092] The benefits of this integration approach are numerous. First, the choice of substrates for physical support of the components is flexible (ex. silicon, glass, ceramic, plastic) and depend on the application of the microsystem. Second, the area of the microsystem can be minimized by placing components within tens of micrometers from each other since electrical leads no longer need to be routed on the platform around the components. The area on top of components can be utilized for routing since the overlay cable is insulated on the top and bottom. This saves significant lateral space since the components can be placed much closer to each other and arranged more efficiently compared to the traditional method where electrical routing determines the lateral space and component arrangement (i.e., that needed for bonding from one component to the platform and from the platform to another component). Third, since wire is not involved in the bonding process, the tab pitch can be much smaller and multiple tabs can be bonded simultaneously, making assembly faster and more efficient. Furthermore, with the elimination of wire bonds, several cables can be stacked and oriented individually as needed. Stacked cable interconnects oriented independently offer design flexibility and simplicity in a small area with insignificant vertical cost since the thickness of the cable is only on the order of a few micrometers. It is worth noting that individually stacked cables are simpler to fabricate than a single cable with multiple metal layers due to planarization problems associated with lithography, especially beyond two or three layers. Fourth, the cable is not limited to the surface of the platform. It can be extended much longer to terminate in a connector or printed circuit board, for example. It can also be bent around the side of the platform to connect to components mounted on the other face as shown in FIG. 24 . In some cases, this circumvents the need for more complex through-wafer interconnect technology needed for compact microsystem integration.
Overlay Cable Fabrication
[0093] The overlay cable is a sheet of polymer carrying metal traces that are insulated above and below. Parylene-C was selected as the structural material for the fabrication of these cables due to its compatibility with low temperature deposition, lithographic patterning, mechanical flexibility and biocompatibility. Fabrication begins with a silicon wafer having a sacrificial layer on the processing side. In this work, three sacrificial layers were explored: PECVD oxide (5000 Å), evaporated titanium (300 Å) and native oxide on bare silicon. Next, the first layer of parylene is deposited at room temperature using a Specialty Coating System PDS 2010. The deposition of parylene occurs on both sides of the wafer at an average thickness of 0.45 μm per gram of dimer. Approximately 5 μm of parylene is deposited but the precise thickness of the film is not a critical parameter. At least a few microns should be deposited since it acts as a structural layer. This layer of parylene is patterned using thick photoresist and dry etched in an oxygen plasma (100 sccm, 100 mTorr, 105W) to define the outline of the cable and tab cutout regions. The etch rate of parylene under these conditions, determined experimentally, is approximately 1600 Å/min. Following the parylene patterning, the interconnect lithography and definition take place. For the interconnect metal, a chromium (300 Å), gold (3500 Å), chromium (300 Å) stack is used and defined using liftoff. A top layer of chromium is used since a second layer of parylene will be later deposited, which has better adhesion to chromium than to gold. The next step is to open the tab regions with lithography and sputter an electroplating seed layer: Cr (300 Å), Au (2000 Å). Due to the 5 μm step height between the wafer and top surface of the parylene, it is critical that sputter metallization, due to its conformal coverage, rather than evaporation is used to deposit an electrically continuous seed layer. For the same reason, the tab regions and the interconnect metallization are defined in two steps rather than one. A single-step metallization will result in poor lithography near the edge of the step. After the deposition of the seed layer, lithography is again used to open the tab regions for electroplating. Before electroplating, an oxygen plasma ash (250 mT, 250W, 1 min) is used to modify the resist surface so that it is hydrophilic to avoid wetting voids in the electroplating solution. The tab regions are then electroplated with gold at a current density of 3 mA/cm2 to a thickness of 4.5 μm to 5 μm. The electroplating resist is stripped in acetone along with the liftoff of the seed layer. The top parylene layer is deposited (˜5 μm), similar to the first layer, patterned and dry etched in the field and tab regions. The final step is to release the individual cables from the wafer. As mentioned, three different sacrificial layers were explored (PECVD oxide: 5000 Å, Ti: 300 Å, native oxide on silicon: 10 Å-20 Å) as well as parylene deposition with and without adhesion promoter (2.5 mi A-174 silane, 250 mi IPA, 250 mi DI H2O). These wafers were successfully released in 1:1 HF:DI H2O. The PECVD oxide sacrificial layer was not only the longest release method (overnight) but also caused the cables to stick to the wafer even after all oxide had been undercut in the HF solution, causing low yield. Using a thin titanium sacrificial layer or bare silicon provides the quickest release (˜30 min) and highest yield. Obviously, using adhesion promoter in the deposition of the first parylene layer makes it more difficult to release the cables, requiring significant agitation. In this fabrication sequence it was found that adhesion promoter is not critical since contact lithography was successful without significant peeling or bubbling of the parylene layer.
[0094] The details of a released parylene cable 30 are shown in the SEM images of FIG. 25 . The tabs 42 overlaying the IC are 75 μm wide and the parylene cutout region 40 is 100 μm on each side, leaving about a 12 μm gap on three sides of the tab. The back side of the cable 30 in the tab regions overlaying the 3-D probe array is shown in the SEM images of FIGS. 26( a )-( d ). As shown in FIG. 26( d ), there remains a thin chromium layer 54 (from the seed layer deposition) on the back side of all tabs 42 after cable release. Chromium cannot be ultrasonically bonded to gold pads, so the cable should be overlaid on the microsystem components with the gold electroplated side facing down. Mask design and fabrication should also account for this packaging requirement. Alternatively, each cable would need to be individually etched in a chromium etchant, which is tedious and not recommended. Photographs of a fabricated parylene cable highlighting the flexibility and scale of the structure are shown in FIGS. 27( a )-( b ) and 28 ( a )-( b ).
Neural Microsystem Assembly and Integration
[0095] The microsystem integration method described thus far using the overlay cable approach has been applied to integrate the front-end of a neural recording microsystem. As described in the present disclosure, the front-end of the neural recording microsystem includes the electrode array and the signal conditioning chip. Recall that it is critical for the signal conditioning circuitry to be as close to the recording sites as possible so that the microvolt signals are not corrupted by noise or leakage, while the rest of the system circuitry can be placed at a distance. To integrate this microsystem a silicon package and overlay cable were designed. This package can hold a 64-channel 3-D array of 4 neural probes using and a 16 channel signal conditioning chip. Although there are 64 available sites, the parylene overlay cable designed in this work is used to transfer only 16 of the 64 channels for demonstrating this integration approach. Active probes capable of site selection of 16 out of 64 channels could easily replace the passive probes. Alternatively, per-channel lead transfers using multiple overlay cables to the 64-channel chip are possible, although not preferable. This integration approach, along with the components involved, is shown in FIG. 29 . The package is made compact by placing the components as close to each other as possible, as shown in FIG. 29 , eliminating the routing lines from the platform. An etched cavity holds the chip such that no components protrude vertically. The cable is also kept compact by making use of the area on top of the chip to route all the leads. The other end of the cable would go to the rest of the microsystem circuitry, but in this case it is designed to be bonded to a PCB connector to transfer power to the chip and outputs from the chip.
[0096] The fabrication of the package starts with a standard silicon wafer approximately 500 μm thick. The first step is to lithographically pattern the front side of the wafer and deposit and liftoff chromium (300 Å) and gold (5000 Å) for the bonding pads between the slots of the 3-D array. Then, the chip cavity is patterned and DRIE etched from the front side to a depth of about 300 μm, which is the thickness of the chip coming from the MOSIS foundry. This cavity opening, measuring 2.2 mm×1.5 mm, includes a 150 μm tolerance all around to account for size differences from chip to chip and for positioning during assembly. Next, the wafer is patterned to define the front-side slot regions and perimeter openings. The challenge here is to conformally coat the photoresist around a 300 μm deep cavity. Since the cavity opening is relatively large, conformal coating was achieved using a non-standard resist spread/spinning technique. This technique involves using a very viscous photoresist (AZ 9260) with a slow and long spread time (500 rpm for 1 min), followed by a spin/dry step (500 rpm for 1 min). This technique was characterized to allow the edges of the cavity to remain protected with resist. The slots and perimeter of the package are then DRIE etched to a depth of 300 μm, which is the height of the probe backend. Since the front-side slot/perimeter depth and the chip cavity depth are the same in this design, a single-step lithography for the front-side etch (cavity and slots) was explored. However, due to the significant differences in the mask opening and aspect ratio, an optimal DRIE etch recipe was not achieved. The difficulty is that the chip cavity was found to etch at nearly twice the rate as the narrow slots, requiring a two step front-side etch. The simplest method for a two step front-side etch is to use the spin technique just described, but a more complicated method involving a shadow mask could also be explored for patterning a deep etched wafer. The final step is to pattern the back side of the wafer and DRIE etch the slots and perimeter (˜200 μm) until the platform is released from the wafer. The platforms are soaked in acetone to remove the photoresist and cleaned with IPA. The top and cross-sectional views of the chip cavity region of the platform are shown in FIGS. 30( a )-( b ), respectively, along with a top view of the populated cavity in FIG. 30( c ).
[0097] In the assembly of this front-end, the 16-channel passive silicon probes with gold plated tabs on the backend are used. First, the probes (4 in parallel) are assembled in the platform using a brass jig and ultrasonically bonded to the pads. These tabs are designed to cover only half of the bonding pad as shown in FIG. 31( a ); the other half is used to bond the tab from the overlay cable. Next, the chip is separately secured on a glass slide using a temporary adhesive and the overlay cable is aligned and tab bonded on one end to the bonding pads on the chip.
[0098] At this point, the chip/cable connections are tested for electrical continuity on a probe station. The measured interconnect resistance for this 1.5 cm cable with 10 μm wide lines is approximately 300 Ω. Following successful testing, the chip is removed from its temporary fixture and moved, along with the bonded cable, into its cavity on the silicon platform. The bottom of the cavity should have a very small amount of silastic that cures over a period of several hours to allow for adjustment during bonding but to eventually secure the chip in place. With the platform fully populated, the chip/cable assembly is adjusted in the cavity so that the front part of the cable is aligned to the probe tab array and ultrasonically tab bonded. The tabs from the cable are designed to fold down towards the probe tabs onto the other half of the platform bonding pad as shown in FIG. 31( b ). Vertically stacked tabs from the probe/cable could also be designed in future versions but would require the chromium (from the seed layer) to be etched from the backside of the tabs. Notice that the interconnect lines are routed to make maximum use of the spacing between probe slots as they run directly on top of slots and other bonding pads. Finally, the backend of the cable is mounted to an acute PCB and wire bonded for power and output leads. The completed platform is removed from the brass assembly jig, ready for testing. Details of the tab bonding of probes/cable onto the platform are shown in the pictures of FIG. 32 . The final integrated device is shown in its most compact form in the photograph of FIG. 33 .
[0099] In summary, the present disclosure presents a new integration method for fully-implantable Microsystems. This method eliminates the interconnect routing conventionally fabricated on the supporting platform allowing components to be arranged in the most compact configurations. The surface area (size) of the microsystem can be significantly reduced and is only limited by the number/size of the components themselves. The electrical lines are carried by a flexible polymer cable (Parylene-C in this work) that is placed directly on top of the components. The interconnect lines on the cable terminate in beam leads that are ultrasonically bonded to the component bondpads. This integration method was applied to the front-end of a neural recording microsystem. The ultrasonically bonded overlay cable approach was validated in-vivo by recording neural signals using passive probes connected the chip while the power and data transfer to and from the chip were carried by the parylene cable. This integrated front-end achieves the most compact low-profile fully-implantable microsystem with zero-rise above the surface of the platform.
[0100] It is anticipated that in other versions of the full microsystem, the remaining components can be integrated on a separate (satellite) platform using a similar approach. The overlay cable can be extended to accommodate the integration of the satellite platform and connected to the front-end platform. Multiple overlay cables can be stacked to aid in simplifying the design and bonding of high-channel count Microsystems with single/multiple components with a negligible cost in vertical rise. This allows not only compact lateral integration but also a physical separation, reducing the electromagnetic interference generated by the wireless components in the microsystem from the sensitive analog front-end. The entire package, except the electrodes, should finally be encapsulated with a biocompatible material such as parylene. | A microsystem comprising a substrate having an aperture formed therethrough. The aperture includes a first cross-section and a second cross-section—the first cross-section being smaller than the second cross-section to define a ledge therebetween. A probe member is disposed within the aperture of the substrate, such that a backend of the probe member defines a cross-section that is greater than the first cross-section of the aperture and smaller than the second cross-section such that the probe member engages the ledge. A plurality of probe shanks extend from the probe member. Each of the probe shanks includes a plurality of leads disposed there along. Each of the leads extending from the probe shanks to an opposing side of the probe member. | 0 |
FIELD OF THE INVENTION
This invention relates generally to radiation concentration methods and means, and more particularly provides an optical method for radiation amassment derived through intrinsic concentrated cyclical accretion of light by passing a parallel beam thereof to a compound double-faced conical optical prism cyclically via plural single faced 100% reflective right-triangular optical prisms in an arrangement defining an endless return path to and through said compound double-faced conical optical prism whereby to produce a controlled single intensified output beam of modified either or both of reduced width and/or length.
BACKGROUND OF THE INVENTION
Concentration of reflected radiation energy, particularly light energy, has encountered many problems in with efficiency, complexity and expense in systems employed in the past.
Prior art believed pertinent to the state of the art relating to the field of the invention include:
Patentee
Number
Date
Downs
4,858,090
August 15, 1989
Julin
1,535,314
April 18, 1925
Sauer
2,168,273
August 1, 1939
Chenausky et al
3,950,712
April 13, 1976
Dorschner
4,818,087
April 4, 1989
Pullen
5,016,995
May 21, 1991
McKeown et al.
5,078,473
January 7, 1992
Downs discloses an ellipsoidal reflector/concentrator for light energy in which light from a source enters an ellipsoidal housing in which the ellipse is rotated about a line passed perpendicularly through the ellipse major axis at the second focus ( 2 ) with the first focus ( 1 ), now a distributed focus ( 1 ), in the form of a circle while the other focus ( 2 ) remains a point focus with the laws of elliptical reflection remaining in effect. This was said to work well with ultrasonic and explosive energy that may be placed along a distributed focus ( 1 ). Such energy, leaving generally perpendicular to the second focus ( 2 ), will strike the surface of the ellipsoid in the proper attitude to be reflected to the second focus ( 2 ).
However, each point along the generator of such energy radiates its energy in all directions so as to introduce a large axial error for much of its energy when trying to use a filament or gas-discharge tube, for a source of light. Even if it were possible to concentrate all of the light energy from such a source of light, the temperature of an image of incoherent light is a laser, the temperature may reach high enough to bring about atomic fusion, according to Downs.
An ellipsoidal reflection system may be provided with the ellipsoidal reflector by passing the axis of rotation through one focus but missing the other with a distributed focus at one end and a point focus at the other end. Such an ellipsoidal reflective system will be conical as it approached the second focus. With multiple reflectors within an ellipse, a phenomenon results when a ray of energy passes through a focus, it will reflect from the inner surface of the ellipse and pass through the other focus. The internal reflective process will, theoretically, go on after each reflection, the ray path will be more nearly aligned with the major axis. A problem with multiple ellipsoidal reflection systems is that a source of energy located at one focus will be in the path of energy after the second reflection. If multiple ellipsoidal reflections are to be utilized, there must not be substance at either focus. The solution offered to this problem was to position the energy source to the side from the ellipsoidal axis running through both focus points with energy from the energy source injected to converge at one focus so that with no physical obstructions at this focus nor at the other focus multiple reflections may occur. According to Downs, many methods of energy ray concentration are feasible with the only requirement being that energy must converge on one focus.
Downs provided an ellipsoidal system wherein an energy source generates energy radiation focussed through a lens to an ellipsoidal point focus (focus 1 ) it is thereby confocal with the main ellipsoidal point focus (focus 1 ). Per Downs, the main ellipsoid was comprised of two ellipsoid reflective sections adjacent two point focus (focus 2 ) with both curved to match a portion of the common ellipsoid. Both sections are curved to match portions of a common ellipsoid. The internally reflected ellipsoid section is shown to encompass an end of the shape of the ellipsoid and has a small opening to permit passage of a narrow beam of energy outward from the ellipsoidal system, and also, opposite end reflective section that reflects energy beams back through point focus (focus 1 ) to pass through the small end opening. A cut out was provided in the ellipsoid reflective section to permit passage of focussed energy beams passed through the lens to pass to and through the point focus 1 .
One way reflector systems that reflect on the inside and pass radiated energy on through from the outside to the inside could be used in place of the aforementioned cutouts, and with it then possible to have energy directing devices directly opposite of each other rather than having to be spaced. Thus it would be possible to use an annular rotated secondary ellipsoidal reflector projecting radiated energy into a primary reflector through an entire 360 degree circle via a band of one way reflector material as a part of the primary reflector.
Downs asserts that it is not practical to make too many passes since energy is not passing through a system focus the first time has a tendency to go further afield with each pass. Further, if a ray of energy misses a focus on the first pass, it can never cross either focus no matter how many passes it makes.
Downs also suggests placing reflectors at the end exit reflector of the reflective system, so that energy rays reflected toward the point focus ( 2 ) are intercepted in front of the point focus ( 2 ) by a hyperboloid reflector and reflected back generally along the system primary axis with much of this reflected energy radiation passing out through the small exit opening in the form of a relatively narrow radiated energy beam. This beam as an output is neither coherent nor monochromatic.
Downs does disclose a reflector/concentrator for light energy where light is repeatedly reflected within an elliptical housing through a narrow opening. However, the reflective arrangement within the ellipsoidal reflector system is complex and depends upon the energy reaching specific focus points.
Sauer provides an optical system comprising a pair of prisms disposed removably or at lease variably spaced in front of a lens. The prisms have angular reflecting surfaces adapted to direct rays of light off the angular surfaces as the rays pass through the prism so as to converge directed to a point on the optical axis of a lens and a plane imagined at the point of intersection of these axes and standing at right angle to the optical axis of the lens in a plane of convergence. The purpose is to provide two pictures in proper stereoscopic relation to each other so that when viewed through suitable optical aids, will fuse into a single picture desired by a stereo optical device. Attention should be given to the angle of incidence of the rays of light upon the reflecting surfaces being angles other than 45 degrees so that the rays diverge to reach the lens.
Pullin provides a radiation focussing device using an annular ring and a central focussing body, the ring having an inwardly facing reflecting surface, the reflecting surface being a part of a surface of a cone with a half-angle of 45 degrees. The circularly focussing body has a peripheral reflecting surface whereupon radiation traveling in radial directions with respect to its axial symmetry (which is the cone axis of the reflecting surface) is directed to a focus and is surrounded by the ring and coaxial with said focus. The shape and effect of the said peripheral is derived from a parabola. The function of the ring is to convert parallel rays into radial rays which impinge upon the peripheral reflecting surface of the focussing body. The ring and the said peripheral surface function as an objective. It appears that the primary usage of the Pullin device is as an optical astronomical telescope for receiving radiant energy.
Julin discloses light dispersing annular prisms which are utilized as plural concentrically arranged groupings for therapeutic application to a human being and allows the light rays to pass through and disperses them into the several kinds of spectral rays suitable for varied therapeutic use. Selected rays are directed to a focus by a selected lens placed in their directed path.
Chenausky et al provide a resonator particularly useful in chemical laser applications, said resonator comprising a ring end mirror, a conical folding mirror and a circular end mirror combined to form an unstable resonator including a radial direction propagation having a gain medium region and a region of axial direction propagation. Chenausky et al provides an output beam which is said to be circular in diameter and has a diameter which is essentially equal to twice the extraction length characteristic of the working medium. The energy extracted by the radial propagating portion of the mode has an approximately uniform distribution in the output beam as a result of the reflective surface area of the conical folding mirror and the spatial variation of the gain of the flow direction of the working medium, the light intensity in the gain region decreases with an increase in the perpendicular distance from the plane at which the gain medium originates.
The maximum power handling capability of the unstable toroidal resonator provided by Chenausky et al is limited for all practical purposes by the power handling capabilities of the circular end mirror. The toroidal mirror has the largest surface area of any of the reflective surfaces and the power handling capability of which is said not to be a limiting factor since the large area experiences the lowest flux density of any of the reflective surfaces exposed to the laser radiation; however, the circular mirror has the incidence flux of highest density and this parameter controls the maximum power from the unstable resonator. The folding mirror experiences a flux density which is higher than that on the circular end mirror and lower than that on the circular end mirror. Problems can arise due to excessive heating in the vicinity of the apex of the folding mirror so that the apex preferably is rounded to avoid a sharp point.
Chenausky et al further discloses that in transferring rays between the radial and axial regions, the conical folding mirror made the radial profile symetrical with respect to both intensity and phase, and optically compensated for spatial gain variation in the flow direction. These functions are accomplished because the higher intensity portions of the radial propagating beam which occur on the upstream side of the beam are distributed along the base of the folding mirror cone, the base of said cone being coplanar with the base of the toroidal end mirror. The lower intensity portions of the radial propagating beam which occur on the downstream ride are distributed along the base of the conical folding mirror where the reflective surface is a minimum. As a result, the intensity profile of the beam is made more uniform in the axial region and in the near field.
The cross-sectional curvature of the toroidal end mirror is circular and has a geometrical axis of symmetry which must be made coincident with the downstream side of the resonant mode in the non-axial region of the resonator (the line passing from the upper portion of the concave reflective surface across the apex of the conical folding mirror). The circular contour collimates the beam from the circular end (toroidal) mirror which is divergent. Alternatively, Chenausky et al proposes that the toroidal mirror contour can be convex and combined with a circular end mirror which is concave or both the toroidal and circular end mirrors made with concave or even non-spherical reflective surfaces such as an off-axis paraboloid.
Dorschner provides an example of an optical storage ring where mirrors are used to produce a non-planar equilateral (skew rhombus) ring path, the mirrors being mounted on a supporting cube having passages cut in the path of a beam of light energy propagating therebetween. The mirrors are positioned on the surface of the cube and produce a non-planar equilateral ring path having path segments in two planes. Mirrors are positioned on the corners of the cube to define the vertices of a tetrahedron circumscribed by the cube. The sensitive axis of such arrangement is along one of the mutually orthogonal principal axes of the cube. The tetrahedral ring is equiangular as well as equilateral; thus all the incidence angles on the mirrors are the same. An orthohedral ring is provided with two mirrors placed on a first of adjacent comers of the cube and two mirrors are placed between the corners of two adjacent corner pairs to provide a path substantially on two of the faces of the cube. Mirrors provide the reflective surfaces of the embodiments disclosed by Dorschner.
McKeown discloses a pyramidal beam splitter for splitting a beam light into several beams at right angles to a reference beam, the beam parallel to the pyramid axis impinging on the apex of the pyramid at right angles to the reference beam, the beam being a laser beam.
The art has long sought means for capturing, concentrating and storing a charge from the input of any parallel radiation source, for example, a light energy source, the charge capable of being discharged in either a rapid or metered manner. Such means would have considerable value in high powered laser usage. Further, metered discharge would be beneficial in industrial applications, medical applications and communications.
Additionally, it would be beneficial to provide an optical system whereby a parallel radiation energy, e.g., light energy, can be rapidly increased in intensity, which can effect rapid amassment of radiation energy by minimum short duration passes through the system with storage of the amassed energy for such selective discharge.
The invention contemplates the use of at least one compound double-faced conical optical prism for receiving a parallel beam consisting of parallel rays of light energy directed from a light energy source to the reflective inner face of the compound double-faced conical optical glass prism, where the light is reflected to the reflective surface to the conical face of an inner centrally concentrically arranged coaxially located conical prism of the compound double-faced conical optical prism where it can be retained and selectively discharged as an multiplied amassed and concentrated intensified beam to a quadrivial prism by which it is split into individual beams and directed to a serial group of 100% reflective single-faced optical prisms disposed in their paths whereby to introduce said split beams back to the compound double-faced conical optical prism in a multiple recycling path repeatably through said compound double-faced conical optical prism, each recycled pass causing the beam to wrap around itself increasing the intensity of said input beam geometrically, said intensified beam capable of being retained within said conical double-faced conical prism, said retained intensified light beam being discharged rapidly by a 100% right-angle isosceles optical discharge prism intercepting the exit path of said intensified light beam.
Additionally, the compound double-faced conical optical prism can be formed as a single unitary optical prism. Alternatively, the system according to the invention can comprise an arrangement of a dual compound double-faced conical optical prism array including a pair of offset, partially superposed pair of compound double-faced conical optical prisms arranged one partially over the other with their axes offset one relative the other.
The invention also contemplates the combination of the conical double-faced prisms into a single body optical prism formed of optical glass and including all the necessary reflective surfaces of the right-angle isosceles prisms as a part thereof.
It is important that the incident light beam be parallel, that is, perpendicular to the entry face of the compound double-faced conical optical prisms. The output intensified emergent beam must exit in a path parallel to the incident beam and is further intensified with each pass through said compound double-faced conical prisms.
SUMMARY OF THE INVENTION
The invention provides an optical system for radiation amassment derived through intensification by cyclical accretion of energy radiation by passing a ninety degree parallel incident light energy beam perpendicular to a compound double-faced conical optical glass prism repetitively cyclically via plural single-faced 100% reflective right-angle isosceles optical prisms arranged in an endless recycled return path to and through said compound double-faced conical optical prism and plural single-faced 100% reflective right-angle isosceles optical prisms. The energy is amassed and concentrated during the continuous passage of the recycled light beam through the optical system and retained within said compound double-faced conical optical prism upon each pass through said system. A right-angle single-faced reflective isosceles optical glass prism can be inserted into the output (the emergent) intensified energy beam upon its exit from the compound double-faced conical optical energy beam to discharge the amassed energy rapidly to a selected receiving means offset from the optical system. The discharge prism can be inserted between any of the prismatic faces except for the conical prism where the energy beam is not parallel.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagrammatic flow representation of the optical system according to the invention;
FIG. 2 is a simplified diagrammatic flow representation of a modified optical system according to the invention shown partially in perspective;
FIG. 3 is a top plan view of the representation of the modified optical system shown in plan view of the modified optical system shown in FIG. 2;
FIG. 4 is a diagrammatic flow representation of an additionally modified optical system according to the invention shown in perspective;
FIG. 5 is a perspective view of an additionally modified embodiment of the optical system according to the invention;
FIG. 6A is a chart illustrating the change in cross-section of the incident light energy beam as it is recycled through the optical system of FIG. 1; and,.
FIG. 6B is a chart illustrating the change in cross-section of the incident light energy beam as it is recycled through the optical system of FIG. 4 .
DESCRIPTION OF PREFERRED EMBODIMENTS
The invention provides an optical system that captures, concentrates and retains a charge of radiation, here light energy, from the source of a parallel energy beam such as a laser, sunlight, etc. which can be retained and discharged in a rapid manner.
The applicant has utilized the behavior of rays of light incident entering normally on one of two perpendicular faces of an optical glass prism whose principal section is an isosceles right-triangle. The rays of light enter the optical glass prism without deviation and strike the hypotenuse face at an angle of 45 degrees, which is greater than the critical angle of glass, they will be totally reflected there and turned through a right angle so that they will emerge in a direction normal to the other of the two perpendicular faces of the prism. None of the light is lost by total reflection in the prism, particularly if the prism is made of good optical glass of high transparency. Then there is little loss of light by absorption in the prism or by reflection upon entering or leaving the prism. While the same optical effect can be produced by a simple plane mirror, a polished metallic surface, such as provided by a plane mirror, has been found to absorb the incident light to a considerable extent.
Applicant has discovered that a light beam, can be intensified by passing a parallel incident light beam perpendicularly through a 100% reflective compound double-faced conical optical glass prism so that the beam is reflected serially at an angle of 45 degrees from one reflective face to the other reflective face also at 45 degrees. The light beam then is reflected at 45 degrees from said other face of the compound double-faced conical optical glass prism directing the concentrated and amassed light beam in a direction parallel to the incident light beam to exit the compound double-faced conical optical glass prism as an amassed and concentrated emergent light beam. The emergent amassed and concentrated light beam is recycled toward the 100% reflective compound double-faced conical optical glass prism along a return path through a series of 100% reflective single-faced right-angle isosceles prisms returning to and through the 100% reflective compound double-faced conical optical glass prism in one or more series of passes. Each pass results in the further amassment and concentration of the incident beam by causing said incident light beam serially to wrap around itself, increasing its intensity exponentially with each full recycled pass-through without loss of any light energy. In one embodiment of the invention, recycling is effected by directing the emergent amassed energy beam to a quadrivial optical glass prism, which is a pyramidial optical glass prism splitting the emergent amassed energy beam into four beams and directing the split beams toward the respective plural 100% reflective right-angle single faced isosceles optical glass prisms. In addition, applicant can effectively retain the accumulated amassed energy within the compound double-faced conical glass prism and discharge the accumulated energy rapidly, even in a singular burst, by intercepting the emergent beam with an 100% reflective right-angle single faced isosceles optical glass prism which can be described as a discharge prism.
The discharge prism can be inserted between any of the prismatic faces except for the faces of the compound double-faced conical optical glass prism. Use of a single compound double-faced conical double-faced conical glass prism will condense the incident beam forming an emergent beam only vertically while use of two compound double-faced prisms in series, as will be hereinafter described, will produce an emergent beam condensed horizontally as well as vertically. Both concentration and amassment can be produced with the optical system of the invention.
Referring to FIG. 1 the optical radiation amassment system according to the invention is represented in diagrammatic flow representation, said system being generally indicated by reference character 10 and comprises a total of fifteen 100% reflective single faced isosceles (right-angle) glass optical prisms, at least one compound 100% reflective double-faced conical optical glass prism 12 , one quadrivial optical glass prism 14 and plural single-faced 100% reflective isosceles glass optical prisms ( 16 a , 16 b , 16 c , 16 d , 16 e , 16 f , 16 g , 16 h , 16 i , 16 j , 16 k 16 l and 16 m ), prisms 16 g , 16 h , 16 i , 16 j , 16 l and 16 m are not each visible but are represented by box 16 x as those prisms located along a path linearly rotated 90 degrees from the linear path within which the prisms 16 a - 16 f are disposed. The quadrivial prism 14 is a single solid rectangular optical glass body 18 including a four-sided optical glass pyramid 20 encapsulated within said rectangular body 18 , said optical glass pyramid 18 having a base 22 , an apex 24 and four right-angle 100% reflective faces 26 a , 26 b , 26 c and 26 d . ( 26 b and 26 c not visible in FIG. 1 ).
The compound 100% reflective double-faced conical glass prism 12 consists of an outer continuous circular ring 28 as a circular outer wall 30 . The circular outer wall 30 has a 100% reflective inner face 32 . The compound 100% double-faced optical glass prism has a top surface 34 , a base surface 36 parallel to said top surface 34 and a central conical recess 38 opening to said top surface 34 and having a 100% conical reflective face 38 and a bottom apex 37 touching the base surface 36 . Both the inner reflective face 32 and the conical reflective face 40 have a curvature of different radii sharing the same center formed to an exact tolerance.
As illustrated in FIG. 1, the incident light beam 42 is directed to the compound 100% reflective double-faced conical optical glass prism 12 from an overhead light source 44 . The incident light beam 42 enters the top surface 34 oriented perpendicular thereto and impacts the 100% reflective inner face 32 of the circular outer wall 30 at an angle of 45 degrees relative thereto and is reflected therefrom at a 45 degree angle toward the central conical recess 38 and the 100% reflective face 40 thereof The light beam 42 impacts the circular reflective face 40 of the central conical recess 38 also at a 45 degree angle and is reflected therefrom at a 45 degree angle, directing the light energy beam 42 in a direction perpendicular toward the base 36 of said compound double-faced conical optical glass prism 12 and exit from the compound double-faced conical glass prism 12 as an emergent light beam 46 directed parallel to the incident light beam 42 , each pass from one internal 100% reflective prism face to the other internal reflective face thereof effecting a three fold concentration increase.
The distance between the 100% reflective face 32 and the 100% reflective face 40 the conical recess 38 is selected to be three (3) inches (7.62 cms ). The incident light energy beam 42 can be in the form of sunlight or any other source of radiant energy, lasers, etc. In another example, if the outer diameter of the compound double-faced conical prism is four (4) inches (10.2 cms) and the diameter of the central conical formation at its base is two (2) inches (5.1 cms), the light energy beam traveling through will be concentrated exactly three (3) times, per each pass . . . that is, three squared (3×3)=9, 9×3=27, 27×3 or 81, etc . . . increased expotentially.
Upon its exit from the compound double-faced 100% reflective conical optical glass prism 12 , the concentrated and/or amassed emergent light beam 46 is directed to the quadrivial prism 14 where it is divided into four split beams, two split beams 48 , 50 being directed respectively along paths 52 , 54 leading to the single-faced 100% reflective right-angle isosceles optical prisms 16 a and 16 d . The other two split beams (not shown but being directed to the paths (not shown) leading to the 100% reflective right-angle isosceles optical prisms 16 g , 16 h , 16 i , 16 j , 16 k , 16 l (also not shown but represented as being within box 16 x .) The paths leading to said 100% reflective single-faced right-angle isosceles optical glass prisms being “rotated” 90 degrees from the paths of the optical prisms 16 a - 16 f The path taken by the split energy beams 48 , 50 in their return to and through and return in the system 10 is represented, in FIG. 1, by the broken lines with the arrows absent. Generally, the return paths normally retrace the paths taken by the incident light beam 42 through the respective 100% reflective single-faced right-angle isosceles optical glass prisms 16 a - 16 f.
Each of the single-faced right-angle isosceles optical glass prisms 16 a - 16 l are provided with their single 100% reflective surfaces 16 a - 16 l ′ along their hypotenuse. The 100% single-faced right-angle isosceles optical glass prisms 16 a - 16 l are arranged spaced at 45 degrees about the compound double-faced conical optical glass prism 12 , the group thereof in two rows, one row diametrically opposite the other row, said one row being illustrated in FIG. 1 while, as mentioned above, the other row is represented as disposed in square box 16 x shown in said FIG. 1 .
Upon exiting from the compound double-faced conical optical glass prism 12 , the amassed and/or concentrated emergent energy beam 46 impacts upon the reflective faces 14 a and 14 b thereof and is split into four (4) split light beams, two of which, 48 and 50 , are reflected at 45 degree angles in opposite directions toward the 100% reflective single-faced right-angle optical glass prisms which are represented as located in the box 16 x.
The split light beams 48 , 50 enter the vertical faces 56 , 58 of the single-reflective faced isosceles prisms 16 a and 16 d respectively, and pass through said prisms 16 a and 16 d to engage the 100% reflective hypotenuse faces 60 , 62 of said respective 100% reflective single-faced isosceles prisms 16 a and 16 d and are reflected toward the horizontal faces 64 , 66 of 100% single-faced right-angle isosceles prisms 16 b and 16 e respectively, entering same through the horizontal faces 68 , 70 thereof, passing through to hit the 100% reflective hypotenuse faces 72 , 74 of said 100% reflective single-faced right-angle optical glass prisms 16 b and 16 e and are reflected at 45 degree angles therefrom, and are directed through the vertical faces 76 , 78 of said 100% reflective single-faced right-angle optical glass prisms 16 b and 16 e , entering said 100% reflective right-angle isosceles prisms 16 c through the respective vertical faces thereof and impact respectively on the 100% reflective hypotenuse faces 80 , 82 of said prisms 16 c and 16 f from which they are reflected at an angle of 45 degrees respectively toward the horizontal faces 84 , 86 of said 100% reflective single-faced right- angle optical glass prisms 16 c and 16 f through which they pass and return to the respective top surface 34 of said compound double faced conical optical glass prism 12 again to enter same in a direction perpendicular to the top surface 34 thereof and begin the return pass, following the return paths 50 , 52 to and through the compound 100% reflective compound double-faced conical optical glass prism 12 reflected from the 100% reflective face 32 of inner wall 30 to the 100% reflective face 40 of the central conical recess 38 to be reflected therefrom so as to exit from the circular base 36 thereof as an additionally concentrated and amassed (thereby intensified) emergent light beam 46 . The resulting additionally concentrated and amassed (thereby intensified) emergent light beam exits to enter the quadrivial prism 14 and,again, follows the return path to and through the 100% single-faced right-angle isosceles prisms 16 a - 16 c and 16 e - 16 f returning to and through the 100% reflective compound double-faced conical optical glass prism 12 , exiting now as a further additionally concentrated and amassed (thereby intensified) emergent light beam 46 . However, the 100% reflective single-faced right-angle optical glass prism 16 m , initially offset from the paths 52 , 54 now functioning as a discharge prism, is mechanically inserted in the paths 52 , 54 , intercepting the further additionally concentrated and amassed (intensified) emergent fight beam 46 and directing same in a direction normal to paths 52 , 54 , effecting the discharge of the said further additionally concentrated and amassed (intensified) light energy which had been accumulated within the system 10 . The degree of the discharge is dependent upon the manipulation of the 100% reflective single-faced right-angle isosceles optical glass prism 16 m (the discharge prism). One can describe the relationship of the respective emergent forms of the amassed and concentrated light beams in their passage as being “wrapped serially within themselves and sharing a mutual core”, the cylindrical beam becoming in stages, succeeding successive oval beams effecting the formation of a linear beam with each pass, resulting in a line, as shown diagrammatically in FIG. 6 A.
Referring now to FIG. 2, a relatively simplified optical system according to the invention also is illustrated in diagrammatic flow representation and designated generally by reference character 100 . The system 100 comprises a 100% reflective compound double-faced conical optical glass prism 102 formed of a circular, dish-shaped configuration having a planar top surface 104 , a circular outer wall 106 , a central conical recess 108 , the apex 110 of which touches the top surface 104 , and a circular base 112 of lesser diameter than the circular outer wall 106 and parallel to said top surface 104 . The circular outer wall 106 has an inner 100% reflective inner face 114 . The central conical recess 108 has a 100% reflective face 109 .
A pair of 100% reflective single-faced right-angle isosceles optical glass prisms 116 , 118 are positioned spaced apart with their vertical faces 120 , 122 respectively equal in height and parallel. The horizontal faces 124 , 126 of said 100% reflective single-faced right-angle isosceles optical glass prisms 116 and 118 are coplanar. The hypotenuse faces 128 , 130 of said 100% reflective single-faced right-angle isosceles optical glass prisms 116 , 118 are 100% reflective. The pair of 100% reflective single-faced right-angle optical glass prisms 116 , 118 are located above the compound double-faced 100% reflective conical prism 102 . An additional 100% reflective single-faced, right-angle isosceles optical glass prism 132 is arranged above the pair of 100% reflective single-faced right-angle isosceles prisms 116 , 118 . The pair of 100 reflective single-faced right-angle optical glass isosceles prisms 116 , 118 are spaced apart to define a gap 134 between the vertical faces 122 , 124 thereof The additional 100% reflective single-faced right-angle optical glass isosceles prism 132 is mounted mechanically linked (as represented) so that it can be mechanically shifted to a position fully between the vertical faces 120 , 122 of the 100% reflective single-faced right-angle optical glass isosceles prisms 116 , 118 sufficiently to permit the additional 100% reflective single-faced right-angle reflective isosceles optical glass prism 132 to be introduced easily between the pair of 100% single-faced isosceles optical glass prisms 116 , 118 so as fully to fill the gap 134 between the said pair of 100% reflective single-faced right-angle optical glass isosceles prisms 116 , 118 when said 100% reflective single-faced right-angle optical glass prism 132 is mechanically shifted via link 140 . The horizontal faces 128 , 130 of the pair of 100 % reflective single-faced right-angle isosceles optical glass prisms 116 , 118 being coplanar, together bridge the horizontal distance between the apex 112 of the central coaxial conical formation 110 and the outer wall 108 of the compound double-faced conical prism 102 .
The additional 100% single-faced right-angle optical glass prism 132 is identical in configuration with the configuration of the 100% reflective single-faced right-angle isosceles 116 , 118 except that it is inverted, that is, the vertical face 136 of said additional single-faced right-angle isosceles optical glass prism 132 , when inserted between the pair of 100% reflective single-faced right-angle isosceles optical glass prisms, 116 , 118 is parallel to the vertical faces 120 , 122 of said prisms 116 and 118 . The 100% reflective single-faced right-angle isosceles optical glass prism 132 is mounted for selective mechanical movement via link 139 to a position (shown in broken line representation in FIG. 3) between the pair of 100% reflective single-faced right-angle isosceles optical glass prisms 116 , 118 , the said prism 132 entering the gap 134 between said 100% reflective single-faced right-angle isosceles prisms 116 , 118 .
In FIG. 2, a vertically directed incident light beam 140 travels along the path represented by the broken line (with arrows) from a light source 142 located above the 100% reflective compound double-faced conical optical glass prism 102 . The incident light beam 140 enters the top surface 104 of the compound double-faced conical optical glass prism in a direction perpendicular to the top surface 104 thereof and strikes the inner reflective face 114 of the outer wall 106 of said compound 100% reflective double-faced conical optical glass prism 102 at a 45 degree angle relative to said reflective face 114 and is reflected in a 45 degree direction relative said reflective face 114 direction inward to the 100% reflective surface 109 of the central conical recess while being amassed and concentrated further by a power of three. The light beam 140 hits the reflective face 109 then is reflected upward at a 45 degree angle relative from said reflective face 109 to enter into the 100% reflective single-faced right-angle isosceles prism 118 through the horizontal surface 126 thereof to strike the reflective inner hypotenuse face 130 of the fight-angle isosceles prism 126 . From the inner hypotenuse face 130 of the prism 118 the light beam 140 then passes through the vertical face 122 of the 100% reflective single-faced right-angle isosceles prism 118 , passes across the gap 134 and enters the right-angle isosceles prism 116 through the vertical face 120 thereof and travels to the hypotenuse face 128 thereof from whence the light beam 140 is reflected at a 45 degree angle toward the horizontal face 120 of the 100% reflective single-faced right angle optical glass prism 118 to return to and enter the compound double-faced conical optical glass prism 102 perpendicular to and through the top surface 104 to impact upon the 100% reflective face 114 , reflecting therefrom again to the 100% reflective single-faced right-angle isosceles optical glass prism 118 . As the light beam 140 , now as an amassed and concentrated light beam 144 approaches the vertical face 122 of the prism 118 , and is about to enter the gap 134 , the additional 100% reflective single-faced right-angle isosceles optical glass prism 132 is mechanically shifted into the gap 134 to intercept the amassed and concentrated light beam 144 and discharge the accumulated energy content of the amassed and concentrated (intensified) light beam 144 rapidly and/or depending upon the manipulation of said additional 100% reflective single-faced right-angle isosceles glass prism 132 . The recycling of the incident (and the intensified) light beam can be continued repeatedly with continuing amassment and concentration (intensification) of the subject light beam with continued recycling passes through the system 100 .
FIG. 3 illustrates in plan view, the compound double-faced conical prism 102 showing the reflective face 114 of the outer wall 106 thereof, with the central conical recess and the apex 112 thereof. The pair of 100% reflective single-faced right-angle isosceles prisms are shown with the light beam represented by reference character 140 and the cross-paths across the gap 134 between the pair of the 100% reflective single-faced right-angle isosceles prisms represented by reference character 134 and the pair of 100% 100% reflective single-faced right-angle prisms being represented by boxes 16 x.
Referring to FIG. 6A, the systems 10 and 100 are capable of concentrating an incident “input” light beam only in a vertical direction, that is gradually reducing the diameter of the cylindrical input light beam in reduced stages, narrowing same from a first reduced oval gradually to form still narrower “compressed oval” to a single line since the beam passes through only a single compound double-faced conical optical glass prism.
Thus, the simplified optical system 100 according to the invention, involves a parallel light beam from a source thereof, permitted to enter the compound double-faced conical prism perpendicular to the top surface thereof. The said light beam strikes the inner reflective face and is reflected inward toward the center conical formation while being amassed and concentrated (intensified) by a power of three (3). The intensified light beam then is reflected upward into the first single-faced right-angle isosceles optical glass prism. The said first single-faced right-angle isosceles optical glass prism reflects the light beam upward into the second single-faced right-angle isosceles prism which reflects the beam across the gap. The size of the unit 100 varies in accordance with the diameter of the incident light beam. For example, the system 100 involves a one (1) inch (2.2 cm) diameter incident light beam.
Directing attention to FIG. 4 in which a modified embodiment of the system according to the invention is illustrated and designated generally by reference character 200 , said system being a dual system consisting of an array formed of a pair of compound double-faced 100% reflective conical optical prisms 202 , 204 , each identical to the compound double-faced conical prism 102 of the system illustrated in FIG. 1 . The dual array system 200 functions in much the same manner as the single array system. The advantage of the dual array system is that the incident energy beam is concentrated in both vertical and horizontal dimensions, while the systems 10 and 100 narrows the light beam only compressing horizontally.
Referring to FIG. 6B, the dual configured system 200 is capable of concentrating an incident “input” light beam both vertically and horizontally, the vertical concentration taking the form of an elongate line while the horizontal concentration effects a decrease in the diameter of the light beam with reduced length eventually to take the form of a dot or point. As represented in FIG. 6B, the first amassment of the cylindrical incident light beam to assume a first amassed emergent light beam results in a compression to an oval cross-section; next, the first amassed emergent light beam has been compressed vertically toward an ever smaller core to form a second resulting emergent amassed light beam which has assumed a reduced diameter cylindrical cross-section; the third pass through results in the second emergent amassed light beam being compressed horizontally to a further amassed emergent light beam formed into a reduced cylindrical cross-section configuration; the fourth pass through results in compression of the reduced cylindrical cross-section configuration to a still further narrowed oval cross-section, a practically linear configuration; and, after the next pass, the further amassed emergent light energy beam; and, a further pass provides a still further amassed emergent light beam having a configuration of a dot or point.
As shown in FIG. 4, the system 200 comprises a pair of compound double-faced conical optical glass prisms 202 , 204 arranged with one compound double-faced conical optical glass prism 202 being vertically offset from and above the other compound double-faced optical glass prism 204 . The compound double-faced optical glass prism 202 has a circular outer wall 206 with an inner 100% reflective face 208 , a circular planar top surface 210 , a circular base 212 having a diameter less than the diameter of the top surface 210 and a central conical recess 214 opening to the top surface 210 of the prism 202 . The conical recess 214 has an apex 217 touching the base 212 . The inner face 208 of outer wall 206 is 100% reflective. The compound double-faced conical optical glass prism 204 has a circular outer wall 216 with an inner reflective face 218 , a circular planar top surface 220 , a circular base 224 having a diameter less than the diameter of the top surface 220 and a central conical recess 226 opening to the top surface 220 . The central conical recess has a 100% reflective surface and an apex 228 which is aligned with the peripheral edge of the base 212 of the compound double-faced optical glass prism 202 .
A pair of 100% reflective single-faced right-angle isosceles optical glass prisms 230 , 232 are arranged in proximity to the compound double-faced conical optical prism 202 with the vertical faces 234 , 236 respectively, parallel and spaced one from the other to define a gap 238 . The horizontal faces 240 and 242 of said prisms 230 and 232 respectively are coplanar. The pair of 100% reflective single-faced right-angle isosceles optical glass prisms 230 , 232 have 100% reflective hypotenuse faces 244 and 246 , respectively. The 100% reflective single-faced right-angle isosceles optical glass prisms 230 and 232 are arranged with their 100% reflective hypotenuse faces 244 and 246 oriented in opposite directions, as shown in FIG. 4 .
A third 100% reflective single-faced right-angle isosceles optical glass prism 248 is positioned spaced below the compound double-faced conical optical glass prism 204 . The 100% reflective single-faced right-angle isosceles optical glass prism 248 has a horizontal face 250 and a vertical face 252 . The horizontal face 250 of prism 248 is oriented facing and parallel to the circular base 224 of prism 204 . A fourth 100% reflective single-faced right-angle isosceles optical glass prism 254 is positioned below the 100% reflective single-faced right-angle isosceles optical glass prism 230 . The prism 254 has a horizontal face 256 and a vertical face 258 and is aligned with prisms 230 and 248 with the horizontal faces 250 and 256 respectively being parallel and the horizontal faces 250 and 256 also being parallel. The prism 254 is oriented so that the 100% hypotenuse reflective face of prism 254 faces upward toward the 100% reflective hypotenuse face 246 of the prism 230 .
An additional 100% reflective single-faced right-angle isosceles optical glass prism 260 is positioned below the compound double-faced conical optical glass prism 204 and is horizontally offset from and above the 100% reflective single-faced right-angle optical glass prism 248 and is mechanically linked for positioning selectively to be translated in a direction horizontally below the compound double-faced conical prism 204 , from its offset position from to a position above and aligned with the 100% reflective single-faced right-angle conical optical prism 254 and is arranged to be mechanically translated from its offset position shown in FIG. 4 (see arrow 254 ′) by broken line, so as to intercept the emergent amassed light energy beam 262 which is directed in a vertical path to the horizontal face 250 effectively to cause the emergent amassed light beam 262 to be discharged rapidly.
In FIG. 5, an additional embodiment of the radiation amassment and concentration optical system according to the invention is designated generally by reference character 300 . The unitary 100% reflective compound double-faced conical optical glass prism 302 is formed as a unitized single unit with all the 100% reflective single-faced right-angle isosceles optical glass prisms being incorporated in the unitary single unit, eliminating all the separate individual prisms but the separate 100% reflective single-faced isosceles conical optical glass discharge prism.
The 100% reflective compound double-faced conical optical glass prism 302 is formed with an outer circular wall 304 and a central conical recess 306 . The outer circular wall 304 has an inner 100% reflective face 305 while the central conical recess 306 carries a 100% reflective surface 307 . The paths traversed by the incident energy beam being within the radial arms 308 , 310 , 312 and 314 unitary with the single unit. A four-sided pyramidal recess 313 is formed at the intersection of said arms 308 , 310 , 312 and 314 at a location with the apex 309 thereof aligned with the bottom apex 311 of the central conical recess 306 formed in the compound double-faced conical optical prism 302 .
Each arm 308 , 310 , 312 and 314 has vertical legs, each formed of optical glass, 15 respectively, 316 , 318 , 320 and 322 . The vertical legs each continue in return-bent arms 324 , 326 , 328 and 330 , also formed of optical glass, each terminates in a 100% reflective hypotenuse angular face 332 , 334 , 336 and 338 . At the return bend of each leg, a 100% reflective hypotenuse angular face 340 , 342 , 344 and 346 , a 100% reflective hypotenuse face is provided.
An incident parallel light beam 345 from a light source 352 enters the top surface of the compound double-faced conical optical glass prism 302 and impacts upon the circular inner reflective face 305 of the outer wall 304 of the compound double-faced conical optical glass prism 302 and is reflected therefrom at a 45 degree angle toward the central conical recess 306 and hits the reflective face 307 of the central conical recess 306 . The light beam 350 then passes through the circular base 342 to impact upon the reflective faces of the pyramidal recess 313 and are split into four beams which pass through the respective arms 308 , 310 , 312 , 314 , vertical legs 316 , 318 , 120 , 322 , return-bent arms 324 , 326 , 328 , 330 to reach the respective hypotenuse faces 332 , 334 , 336 , 338 through the terminal portions of said arms and are directed in return paths toward the reflective surfaces 305 and 307 following the return paths through the said arms and four-sided pyramid and through said arms, said hypotenuse faces 346 , 348 , 344 , 350 in return paths back to the four-sided pyramid and including the arms, legs, return bent legs and terminal arms. A 100% reflective single-faced right-angle isosceles optical glass prism 348 is mounted outside the unitary glass prism 302 and is arranged for selective mechanical movement (see arrow 352 and broken line outline 349 of said prism 348 ) to enter between the conical recess 306 and the four-sided pyramidal recess 313 to intercept the emergent amassed concentrated light beams and discharge the amassed light energy thereof to a selected location.
The radiation amassment system according to the invention, in the rapid discharge mode, can be utilized for high-powered laser operations, while the metered discharge system can be employed in areas of industry, medicine and communications where vastly increased power can be of value.
Although the best modes contemplated for carrying out the present invention have been described, it will be apparent that modification and variation may be made without departing from the invention as defined in the appended claims. | There is disclosed an optical system for light beam amassment and concentration derived through intensification by cyclical accretion of light energy by passing a parallel light beam perpendicular to a 100% reflection double-faced conical optical glass prism repetitively cyclically via plural 100% reflective single-faced right-angle isosceles optical prisms arranged in a path surrounding said compound optical glass prism defining an endless recycled return path to and through said compound optical glass prism, the amassment occurring during the passage of said light beam through said compound conical prism to be reflected from the conical prism as an emergent amassed and concentrated light beam occasioned by each repeated pass to and from said conical portion of said compound prism and to and through a beam-splitting quadrivial prism to said return path to said compound prism and the conical prism portion thereof and emergence therefrom, an single-faced right-angle isosceles prism arranged to intercept said emergent light beam for discharge of the light energy therefrom. Single, double and unitary compound optical prisms are disclosed. | 6 |
This is a National Phase Application filed under 35 U.S.C. §371 as a national stage of PCT/IL2009/000964, filed on Oct. 11, 2009, an application claiming the benefit under 35 USC 119(e) of U.S. Provisional Application No. 61/103,054, filed on Oct. 6, 2008, and an application claiming the benefit under 35 USC 119(e) of U.S. Provisional Application No. 61/165,011, filed on Mar. 31, 2009, the content of each of which is hereby incorporated by reference in its entirety.
FIELD OF THE INVENTION
This invention relates to compositions comprising diastereomeric CB receptor agonists, uses thereof and methods of their preparation.
BACKGROUND OF THE INVENTION
The following publications are relevant for describing the state of the art in the field of the invention
1. L. Hanus, et al. Proc. Natl. Acad. Sci, U.S.A. 96:14228-14233, 1999. 2. O. Ofek, et al. Proc. Natl. Acad. Sci. U.S.A. 103:696-701, 2006. 3. I. Bab, et al. J. Neuroendocrinol. 20 Suppl 1:69-74, 2008. 4. L. Hanus, et al. Org. Biomol. Chem. 3:1116-1123, 2005. 5. W. A. Devane, et al. Science. 258:1946-1949, 1992. 6. S. Munro, et al. Nature. 365:61-65, 1993. 7. S. M. Miguel, et al. J. Biol. Chem. 280:37495-37502, 2005. 8. J. M. Alexander, et al. J. Bone Min. Res. 16:1665-1673, 2001. 9. I. Bab, et al. WO 2004/103,410 10. E. Fride et al. U.S. Pat. No. 6,864,291 11. R. Mechoulam et al. U.S. Pat. No. 5,434,295
In vertebrates, skeletal mass is determined by continuous remodeling consisting of the concerted and balanced action of osteoclasts, the bone resorbing cells, and osteoblasts, the bone forming cells.
Osteoporosis, the most prevalent degenerative disease in developed countries, results from the impairment of this balance, leading to bone loss and increased fracture risk. We have recently reported the expression of functional type 2 cannabinoid receptor (CB2) in bone cells.
The CB2 specific agonist HU-308 (WO 2004/103410; Hanu{hacek over (s)} et al, 1999), stimulates in vitro osteoblastogenesis and inhibits osteoclastogenesis. In mice, HU-308 stimulates bone formation and inhibits bone resorption, thus attenuating ovariectomy (OVX)-induced bone loss (Ofek et al, 2006). In another mouse model it rescues OVX-induced bone loss (Bab et al, 2008).
SUMMARY OF THE INVENTION
The compound of general formula (I):
comprises three stereogenic centers, namely: carbon atom in position 3, carbon atom in position 4 and carbon atom in position 6 (substituents R 1 , R 6 , R 7 and R 9 are defined herein below). Thus, compound of general formula (I) may exist in any one of the stereoisomeric forms, indicated in Table 1 below.
TABLE 1
CIP configuration of diastereomers
of compounds of general formula (I)
CIP
CIP
CIP
Stereoisomer
configuration
configuration
configuration
No.
of position 3
of position 4
of position 6
1 (HU-433)
R
R
R
2
S
R
R
3
R
S
S
4 (HU-308)
S
S
S
5
R
R
S
6
S
R
S
7
R
S
R
8
S
S
R
However, it is noted that since positions 4 and 6 are both located at the bridgeheads of the bicyclic ring system, their stereochemistry is interconnected and diastereomers (3R, 4R, 6S), (3S, 4R, 6S), (3R, 4S, 6R) and (3S, 4S, 6R) (corresponding to diastereomers 5, 6, 7 and 8 in above table) do not exist under typical processing and thermal conditions.
U.S. Pat. No. 6,864,291 disclosed a compound of general formula (I) having a configuration of (3S, 4S) (HU-308) being essentially free from its only enantiomer (having (3R, 4R) configuration), compositions and uses thereof.
The compound of general formula (I′):
comprises four stereogenic centers, namely: carbon atom in position 1, carbon atom in position 3, carbon atom in position 4 and carbon atom in position 6 (substituents R 1 , R 6 , R 7 and R 9 are defined herein below). Thus, compound of general formula (I′) may exist in any one of the stereoisomeric forms, indicated in Table 2 below.
TABLE 2
CIP configuration of diastereomers
of compounds of general formula (I′)
CIP
CIP
CIP
CIP
Stereoisomer
configuration
configuration
configuration
configuration
No.
of position 1
of position 3
of position 4
of position 6
1
R
R
R
R
2
S
R
R
R
3
R
S
R
R
4
S
S
R
R
5
R
R
S
S
6
S
R
S
S
7
R
S
S
S
8
S
S
S
S
9
R
R
R
S
10
S
R
R
S
11
R
S
R
S
12
S
S
R
S
13
R
R
S
R
14
S
R
S
R
15
R
S
S
R
16
S
S
S
R
However, it is noted that since positions 4 and 6 are both located at the bridgeheads of the bicyclic ring system, their stereochemistry is interconnected and diastereomers (1R, 3R, 4R, 6S), (1S, 3R, 4R, 6S), (1R, 3S, 4R, 6S), (1S, 3S, 4R, 6S), (1R, 3R, 4S, 6R), (1S, 3R, 4S, 6R), (1R, 3S, 4S, 6R) and (1S, 3S, 4S, 6R) (corresponding to stereoisomers 9, 10, 11, 12, 13, 14, 15, 16 in Table 2 above) do not exist under typical processing and thermal conditions.
The present invention provides a composition comprising the (3R, 4R, 6R)-diastereomer of a compound of general formula (II):
said composition having diastereomeric ratio of between about 50%:50% to about 100%:0%; wherein
is a single or double bond;
R 1 is independently selected from —R 2 OR 3 , —C(═O)R 4 , —OC(═O)R 5 ;
R 2 is a C 1 -C 5 straight or branched alkylene;
R 3 is selected from the group consisting of H, —C(═O)OH, straight or branched C 1 -C 5 alkyl, straight or branched C 1 -C 5 acyl, straight or branched C 1 -C 5 amide;
R 4 , and R 5 are independently selected from the group consisting of H, OH, straight or branched C 1 -C 5 alkyl, straight or branched C 1 -C 5 alkoxy, straight or branched C 1 -C 5 amine;
R 6 and R 7 are each independently selected from H, and —OR 8 wherein R 8 is a straight or branched C 1 -C 5 alkyl, provided that at least one of R 6 and R 7 is different than H (i.e. provided that at least one of R 6 and R 7 is —OR 8 ); and
R 9 is independently selected from an optionally substituted straight or branched C 6 -C 12 alkyl, an optionally substituted straight or branched C 5 -C 9 alkoxy, an optionally substituted straight or branched C 1 -C 7 ether.
In a further aspect, the invention provides a composition comprising the (3R, 4R, 6R)-diastereomer of a compound of general formula (II), said composition having diatereomeric excess of between about 0% to about 100%; wherein is a single or double bond; R 1 is independently selected from —R 2 OR 3 , —C(═O)R 4 , —OC(═O)R 5 ; R 2 is a C 1 -C 5 straight or branched alkylene; R 3 is selected from the group consisting of H, straight or branched C 1 -C 5 alkyl, straight or branched C 1 -C 5 acyl, straight or branched C 1 -C 5 amide; R 4 , and R 5 are independently selected from the group consisting of H, OH, straight or branched C 1 -C 5 alkyl, straight or branched C 1 -C 5 alkoxy, straight or branched C 1 -C 5 amine; R 6 and R 7 are each independently selected from H, and —OR 8 wherein R 8 is a straight or branched C 1 -C 5 alkyl, provided that at least one of R 6 and R 7 is different than H; and R 9 is independently selected from an optionally substituted straight or branched C 6 -C 12 alkyl, an optionally substituted straight or branched C 5 -C 9 alkoxy, an optionally substituted straight or branched C 1 -C 7 ether.
It is noted that in an embodiment where R 1 is —R 2 OR 3 , R 2 is a C 1 -C 5 straight or branched alkylene and R 3 is selected from the group consisting of H (i.e. leading to a substitution with an alcohol group), straight or branched C 1 -C 5 alkyl (i.e. leading to a substitution with an ether group), straight or branched C 1 -C 5 acyl (i.e. leading to a substitution with an ester group), —C(═O)OH (i.e. leading to a substitution with a —C 1 -C 5 alkyl-OC(═O)OH group) and a straight or branched C 1 -C 5 amide (i.e. leading to a substitution with an amide ester group).
In another embodiment where R 1 is —C(═O)R 4 , R 4 is selected from a group consisting of H (i.e. leading to a substitution with an aldehyde group); OH, (i.e. leading to a substitution with an acetic acid group), straight or branched C 1 -C 5 alkyl (i.e. leading to a substitution with a ketone group), straight or branched C 1 -C 5 alkoxy (i.e. leading to a substitution by a —C(═O)OR group) and a straight or branched C 1 -C 5 amine (i.e. leading to a substitution by a —C(═O)NHR or —C(═O)NR′R group).
In a further embodiment where R 1 is —OC(═O)R 5 , R 5 is selected from a group consisting of H (i.e. leading to a substitution with an aldehyde group); OH (i.e. leading to a substitution with an —OC(═O)OH group), straight or branched C 1 -C 5 alkyl (i.e. leading to a substitution with a —OC(═O)R group), straight or branched C 1 -C 5 alkoxy (i.e. leading to a substitution by a —OC(═O)OR group) and a straight or branched C 1 -C 5 amine (i.e. leading to a substitution by a —OC(═O)NHR or —OC(═O)NRR′ group).
In one embodiment of the present invention is a double bond. Thus, a compound of formula (II) is:
wherein R 1 , R 6 , R 7 , and R 9 are have the same meaning as defined hereinabove.
In another embodiment of the present invention is a single bond. Thus, a compound of formula (II) is:
wherein R 1 , R 6 , R 7 , and R 9 are have the same meaning as defined hereinabove.
The term “diastereomeric ratio” as used herein is meant to encompass the ratio of the percentage of one diastereoisomer in a mixture to that of another diastereoisomer of a compound of formula (I).
Thus, in one embodiment when indicates a double bond, said diastereomeric ratio indicates the percentage ratio between (3R, 4R, 6R)-diastereomer of a compound of general formula (I) (compound of formula (III)), and each of (3S, 4R, 6R)- or (3R, 4S, 6S)-diastereomers, all of which (together or individually) may be present in said composition of the invention.
When a composition of the invention has a diastereomeric ratio of 50%:50%, it should be understood that the ratio between the (3R, 4R, 6R)-diastereomer of a compound of general formula (I) (compound of formula (III)) and any one of the diastereomers (3S, 4R, 6R)- or (3R, 4S, 6S)-diastereomer, present in said composition is about 1:1. When a composition of the invention has a diastereomeric ratio of about 100%:0%, it should be understood that the composition comprises essentially only the (3R, 4R, 6R)-diastereomer of a compound of general formula (I), (compound of formula (III)). Thus, the composition of the present invention may comprise any mixture of (3R, 4R, 6R)-diastereomer of a compound of general formula (I) (compound of formula (III)) with one or more of its diastereomers ((1S; 4R, 6R)- or (3R, 4S, 6S)-diastereomers), such as for example a composition having a diatereomeric ratio of 50%:50%, 70%:30%, 80%:20%, 90%:10%, 95%:5%, 97%:3%, 99%:1% or 100%:0%. In some embodiments of the invention, said diastereomeric ratio is at least 97%:3%.
Thus, in another embodiment when indicates a single bond, said diastereomeric ratio indicates the percentage ratio between (1R, 3R, 4R, 6R)-diastereomer of a compound of general formula (I′) (compound of formula (IV)) and each of (1S, 3R, 4R, 6R)-, (1R, 3S, 4S, 6S), (1R, 3S, 4R, 6R)-, (1S, 3S, 4R, 6R)-, (1R, 3R, 4S, 6S)— or (1S, 3R, 4S, 6S)-diastereomers, all of which (together or individually) may be present in said composition of the invention.
When a composition of the invention has a diastereomeric ratio of 50%:50%, it should be understood that the ratio between the (1R, 3R, 4R, 6R)-diastereomer of a compound of general formula (I′) (compound of formula (IV)) and any one of the diastereomers (1S, 3R, 4R, 6R)-, (1R, 3S, 4S, 6S), (1R, 3S, 4R, 6R)-, (1S, 3S, 4R, 6R)-, (1R, 3R, 4S, 6S)— or (1S, 3R, 4S, 6S)-diastereomer, present in said composition is about 1:1. When a composition of the invention has a diastereomeric ratio of about 100%:0%, it should be understood that the composition comprises essentially only the (1R, 3R, 4R, 6R)-diastereomer of a compound of general formula (I′) (compound of formula (IV)). Thus, the composition of the present invention may comprise any mixture of (1R, 3R, 4R, 6R)-diastereomer of a compound of general formula (I′) (compound of formula (IV)) with one or more of its diastereomers ((1S, 3R, 4R, 6R)-, (1R, 3S, 4S, 6S), (1R, 3S, 4R, 6R)-, (1S, 3S, 4R, 6R)-, (1R, 3R, 4S, 6S)— or (1S, 3R, 4S, 6S)-diastereomers), such as for example a composition having a diatereomeric ratio of 50%:50%, 70%:30%, 80%:20%, 90%:10%, 95%:5%, 97%:3%, 99%:1% or 100%:0%. In some embodiments of the invention, said diastereomeric ratio is at least 97%:3%.
In yet a further embodiment when indicates a single bond, said diastereomeric ratio indicates the percentage ratio between (1S, 3R, 4R, 6R)-diastereomer of a compound of general formula (I′) (compound of formula (IV)) and each of (1R, 3R, 4R, 6R)-, (1S, 3S, 4S, 6S), (1R, 3S, 4R, 6R)-, (1S, 3S, 4R, 6R)-, (1R, 3R, 4S, 6S)- or (1S, 3R, 4S, 6S)-diastereomers, all of which (together or individually) may be present in said composition of the invention.
When a composition of the invention has a diastereomeric ratio of 50%:50%, it should be understood that the ratio between the (1S, 3R, 4R, 6R)-diastereomer of a compound of general formula (I′) (compound of formula (IV)) and any one of the diastereomers (1R, 3R, 4R, 6R)-, (1S, 3S, 4S, 6S), (1R, 3S, 4R, 6R)-, (1S, 3S, 4R, 6R)-, (1R, 3R, 4S, 6S)- or (1S, 3R, 4S, 6S)-diastereomer, present in said composition is about 1:1. When a composition of the invention has a diastereomeric ratio of about 100%:0%, it should be understood that the composition comprises essentially only the (1S, 3R, 4R, 6R)-diastereomer of a compound of general formula (I′) (compound of formula (IV)). Thus, the composition of the present invention may comprise any mixture of (1S, 3R, 4R, 6R)-diastereomer of a compound of general formula (I′) with one or more of its diastereomers ((1S, 3R, 4R, 6R)-, (1R, 3S, 4S, 6S), (1R, 3S, 4R, 6R)-, (1S, 3S, 4R, 6R)-, (1R, 3R, 4S, 6S)— or (1S, 3R, 4S, 6S)-diastereomers), such as for example a composition having a diatereomeric ratio of 50%:50%, 70%:30%, 80%:20%, 90%:10%, 95%:5%, 97%:3%, 99%:1% or 100%:0%. In some embodiments of the invention, said diastereomeric ratio is at least 97%:3%.
The term “diatereomeric excess” as used herein is meant to encompass the subtraction of the mole fraction of one diastereoisomer (D 1 ) from the mole fraction of another diastereoisomer (D 2 ) in a composition, i.e. D 1 -D 2 . This term may alternatively relate to the percent diastereoisomer excess as 100%*(D 1 -D 2 ).
Thus, in one embodiment when indicates a double bond, said diastereomeric excess indicates the excess in a composition of the invention of (3R, 4R, 6R)-diastereomer of a compound of general formula (I) with respect to each of (3S, 4R, 6R)-, or (3R, 4S, 6S)-, diastereomer of compound of general formula (I), all of which (together or individually) may be present in said composition of the invention.
When the diastereomeric excess of a composition of the invention is 0% the mole fraction of (3R, 4R, 6R)-diastereomer of a compound of general formula (I), is essentially equal to the mole fraction of any one of (3S, 4R, 6R)-, or (3R, 4S, 6S)-diastereomer of compound of general formula (I). When the diastereomeric excess of a composition of the invention is 100% the composition comprises substantially only the (3R, 4R, 6R)-diastereomer of a compound of general formula (I). Thus, the composition of the present invention may comprise any mixture of (3R, 4R, 6R)-diastereomer of a compound of general formula (I) with one or more of its diastereomers ((3S, 4R, 6R)-, or (3R, 4S, 6S)-diastereomers), such as for example a composition having a diastereomeric excess of 0%, 5%, 10%, 20%, 30%, 50%, 80%, 90%, 95%, 97%, 98%, 99%, or 100%. In some embodiments of the invention, said diastereomeric excess is at least 97%.
In another embodiment when indicates a single bond, said diastereomeric excess indicates the excess in a composition of the invention of (1R, 3R, 4R, 6R)-diastereomer of a compound of general formula (I′) (compound of formula (IV)) with respect to each of (1S, 3R, 4R, 6R)-, (1R, 3S, 4S, 6S), (1R, 3S, 4R, 6R)-, (1S, 3S, 4R, 6R)-, (1R, 3R, 4S, 6S)- or (1S, 3R, 4S, 6S)-diastereomers, all of which (together or individually) may be present in said composition of the invention.
When the diastereomeric excess of a composition of the invention is 0% the mole fraction of (1R, 3R, 4R, 6R)-diastereomer of a compound of general formula (I′) (compound of formula (IV)), is essentially equal to the mole fraction of any one of (1S, 3R, 4R, 6R)-, (1R, 3S, 4S, 6S), (1R, 3S, 4R, 6R)-, (1S, 3S, 4R, 6R)-, (1R, 3R, 4S, 6S)- or (1S, 3R, 4S, 6S)-diastereomers. When the diastereomeric excess of a composition of the invention is 100% the composition comprises substantially only the (1R, 3R, 4R, 6R)-diastereomer of a compound of general formula (I′) (compound of formula (IV)). Thus, the composition of the present invention may comprise any mixture of (1R, 3R, 4R, 6R)-diastereomer of a compound of general formula (I′) (compound of formula (IV)) with one or more of its diastereomers ((1S, 3R, 4R, 6R)-, (1R, 3S, 4S, 6S), (1R, 3S, 4R, 6R)-, (1S, 3S, 4R, 6R)-, (1R, 3R, 4S, 6S)- or (1S, 3R, 4S, 6S)-diastereomers), such as for example a composition having a diastereomeric excess of 0%, 5%, 10%, 20%, 30%, 50%, 80%, 90%, 95%, 97%, 98%, 99%, or 100%. In some embodiments of the invention, said diastereomeric excess is at least 97%.
In yet another embodiment when indicates a single bond, said diastereomeric excess indicates the excess in a composition of the invention of (1S, 3R, 4R, 6R)-diastereomer of a compound of general formula (I′) (compound of formula (IV)) with respect to each of (1R, 3R, 4R, 6R)-, (1S, 3S, 4S, 6S), (1R, 3S, 4R, 6R)-, (1S, 3S, 4R, 6R)-, (1R, 3R, 4S, 6S)- or (1S, 3R, 4S, 6S)-diastereomers, all of which (together or individually) may be present in said composition of the invention.
When the diastereomeric excess of a composition of the invention is 0% the mole fraction of (1S, 3R, 4R, 6R)-diastereomer of a compound of general formula (I′) (compound of formula (IV)), is essentially equal to the mole fraction of any one of (1R, 3R, 4R, 6R)-, (1S, 3S, 4S, 6S), (1R, 3S, 4R, 6R)-, (1S, 3S, 4R, 6R)-, (1R, 3R, 4S, 6S)- or (1S, 3R, 4S, 6S)-diastereomers. When the diastereomeric excess of a composition of the invention is 100% the composition comprises substantially only the (1S, 3R, 4R, 6R)-diastereomer of a compound of general formula (I′) (compound of formula (IV)). Thus, the composition of the present invention may comprise any mixture of (1S, 3R, 4R, 6R)-diastereomer of a compound of general formula (I′) (compound of formula (IV)) with one or more of its diastereomers ((1R, 3R, 4R, 6R)-, (1S, 3S, 4S, 6S), (1R, 3S, 4R, 6R)-, (1S, 3S, 4R, 6R)-, (1R, 3R, 4S, 6S)- or (1S, 3R, 4S, 6S)-diastereomers), such as for example a composition having a diastereomeric excess of 0%, 5%, 10%, 20%, 30%, 50%, 80%, 90%, 95%, 97%, 98%, 99%, or 100%. In some embodiments of the invention, said diastereomeric excess is at least 97%.
In another embodiment, a composition of the invention has an enantiomeric excess of between about 100% to more than about 0%.
The term “enantiomeric excess” (also denoted “ee”) is meant to encompass a percent excess of an enantiomer (E 1 or E 2 ) over the racemic mixture (1:1 mixture of E 1 and E 2 ), in accordance with eq. 1 below:
ee
=
E
1
-
E
2
E
1
+
E
2
*
100
=
%
E
1
-
%
E
2
(
eq
.
1
)
Thus, where referring to ee value of 100% of, for example, enantiomer E 1 it should be understood to encompass substantially only one enantiomer (E 1 ). When referring to ee value of more than about 0% of, for example, enantiomer E 1 it should be understood to encompass non racemic mixtures of E 1 and E 2 .
In one embodiment, when indicates a double bond, said ee indicates the percentage excess between the (3R, 4R, 6R) stereoisomer of a compound of general formula (I) or (III), and its enantiomer (3S, 4S, 6S).
In another embodiment, when indicates a single bond, said ee indicates the percentage excess between the (1R, 3R, 4R, 6R) stereoisomer of a compound of general formula (I′) or (IV), and its enantiomer (1S, 3S, 4S, 6S).
In yet a further embodiment, when indicates a single bond, said ee indicates the percentage excess between the (1S, 3R, 4R, 6R) stereoisomer of a compound of general formula (I′) or (IV), and its enantiomer (1R, 3S, 4S, 6S).
In some embodiments, R 1 is —R 2 OR 3 , wherein R 2 and R 3 are as defined hereinabove. In a further embodiment R 2 is —CH 2 —. In some other embodiments R 6 is H and R 7 is —OR 8 , wherein R 8 is a straight or branched C 1 -C 5 alkyl. In other embodiments R 7 is H and R 6 is —OR 8 , wherein R 8 is a straight or branched C 1 -C 5 alkyl. In some other embodiments, R 6 and R 7 are each independently —OR 8 , wherein R 8 is a straight or branched C 1 -C 5 alkyl. In some other embodiments R 9 is an optionally substituted branched C 6 -C 12 alkyl.
As used herein, the term “alkyl” refers to a straight or branched chain hydrocarbon having from one to five carbon atoms, or from one to seven carbon atoms, or from five to nine carbon atoms, or from six to twelve carbon atoms. Examples of “alkyl” as used herein include, but are not limited to, methyl, ethyl, propyl, n-butyl, n-pentyl, isobutyl, and isopropyl, tert-butyl, and the like.
As used herein the term “alkylene” refers to a saturated, divalent, branched or straight hydrocarbon group having from one to five carbon atoms. Non-limiting examples of C 1-5 -alkylene groups include, methylene, ethylene, 1,2-propylene, 1,3-propylene, butylene, isobutylidene, pentylene, hexylene and the like.
As used herein the term “ester” is meant to encompass an —COOR group wherein R is an alkyl as defined herein above.
A used herein the term “ether” refers to an —R′OR group, wherein R′ is a C 1 -C 7 straight or branched alkylene group and R is a C 1 -C 7 straight or branched alkyl group.
As used herein, the term “alkoxy” refers to an RO— group, where R is alkyl as defined above.
As used herein the term “C 1 -C 7 amide” refers to a monoalkyl amide (—CONHR) or dialkyl amide (—CONRR′), wherein R and R′ are independently a C 1 -C 7 straight or branched alkyl.
As used herein the term “C 1 -C 5 amine” refers to an —NHR or —NRR′ group wherein R and R′ are independently a C 1 -C 5 straight or branched alkyl.
As used herein the term “C 1 -C 5 alkoxy” refers to a —OR group wherein R is a C 1 -C 5 alkyl.
As used herein the term “C 1 -C 5 acyl” refers to a —C(═O)R group wherein R is a straight or branched C 1 -C 5 alkyl.
The term “optionally substituted” as used herein means that the groups in question are either unsubstituted or substituted with one or more of the substituents such as for example those specified above, phenyl, substituted phenyl, aryl, heteroaryl, cycloalkyl, heterocycloalkyl, halogen (—F, —Cl, —Br, —I). When the groups are substituted with more than one substituent the substituents may be the same or different and said substitution may occur at any position on the substituted group (i.e. at a terminal or any mid-chain position or both).
In an embodiment of the present invention, said compound of formula (II) is the following compound (HU-433):
In some embodiments of the invention said composition is a pharmaceutical composition. When referring to pharmaceutical compositions comprising a compound of the subject invention it should be understood to encompass admixtures of compounds of the invention, with pharmaceutically acceptable auxiliaries, and optionally other therapeutic agents. The auxiliaries must be “acceptable” in the sense of being compatible with the other ingredients of the composition and not deleterious to the recipients thereof.
Pharmaceutical compositions include those suitable for oral, rectal, nasal, topical (including transdermal, buccal and sublingual), vaginal or parenteral (including subcutaneous, intramuscular, intravenous and intradermal) administration or administration via an implant. The compositions may be prepared by any method well known in the art of pharmacy. Such methods include the step of bringing in association compounds used in the invention or combinations thereof with any auxiliary agent.
Auxiliary agent(s), also named accessory ingredient(s), include those conventional in the art, such as carriers, fillers, binders, diluents, disintegrants, lubricants, colorants, flavouring agents, anti-oxidants, and wetting agents.
Pharmaceutical compositions suitable for oral administration may be presented as discrete dosage units such as pills, tablets, dragées or capsules, or as a powder or granules, or as a solution or suspension. The active ingredient may also be presented as a bolus or paste. The compositions can further be processed into a suppository or enema for rectal administration.
The invention further includes a pharmaceutical composition, as hereinbefore described, in combination with packaging material, including instructions for the use of the composition for a use as hereinbefore described.
For parenteral administration, suitable compositions include aqueous and non-aqueous sterile injection. The compositions may be presented in unit-dose or multi-dose containers, for example sealed vials and ampoules, and may be stored in a freeze-dried (lyophilised) condition requiring only the addition of sterile liquid carrier, for example water, prior to use.
For transdermal administration, e.g. gels, patches or sprays can be contemplated. Compositions or formulations suitable for pulmonary administration e.g. by nasal inhalation include fine dusts or mists which may be generated by means of metered dose pressurized aerosols, nebulisers or insufflators.
The exact dose and regimen of administration of the composition will necessarily be dependent upon the therapeutic or nutritional effect to be achieved and may vary with the particular formula, the route of administration, and the age and condition of the individual subject to whom the composition is to be administered.
The inventors of the present application found that a composition comprising substantially HU-433, retained the CB2 specificity, with nearly 2-fold higher binding potency, and respective 1000- and 100-fold higher in vitro and in vivo skeletal activities, compared to HU-308. Thus, in some embodiments of the present invention there is provided a composition capable of binding to a CB receptor.
The term “CB receptor” is meant to encompass a cannabinoid G-protein coupled receptor, defined by their capability to bind to cannabinoids and/or endocannabinoids. In some embodiments said receptor is a CB1 (cannabinoid receptor Type 1) and/or CB2 receptor (cannabinoid receptor Type 2). In other embodiments said receptor is a CB2 receptor (cannabinoid receptor Type 2).
CB1 subtype receptor is mainly expressed in the brain, lungs, liver and kidneys. CB2 subtype receptor is mainly expressed in the immune system and in hematopoietic cells.
When referring to “binding” of a composition of the invention to a CB receptor it is meant to include any type of association between a composition of the invention and a CB receptor, which may activate said bound receptor.
In some embodiments said composition is capable of being bound to CB1 and CB2 receptors. When both receptors are capable of being bound by a composition of the invention, the extent of binding may be identical or different. In some embodiments a composition of the invention binds to CB2 receptor to a greater extent as compared with the binding to CB1 receptor. Thus resulting in an activation of CB2 receptor to a greater amount compared with activation of CB1 receptor. In some embodiments activation of the CB2 receptor by a composition of the invention is at least 10 times higher than the activation of the CB1 receptor. In other embodiments composition of the invention is capable of binding to CB2 receptor.
In other embodiments said binding of a CB receptor by a composition of the invention is associated with a beneficial therapeutic effect, such as the treatment of a disease or disorder. Examples of disease wherein a beneficial therapeutic effect is evident by activation of CB receptor (in some embodiments, with low or no activation of CB1 receptor) are: inflammation (Benito et al., Brit. J. Pharmacol. 153, 277-285, 2008), pain, allergies, neurological diseases—multiple sclerosis (Docagne et al., Expert Opin. Therapeutic Targets, 12, 185-185, 2008), Alzheimer's (Benito et al., ibid), amyotropic lateral sclerosis (Kim et al., Eur J Pharmacol, 542, 100-105, 2006), HIV-induced encephalitis (Benoto et al., J. Neurosci. 25, 2530-2536, 2005), neuropathic pain (Zhang et al., Eur, J. Neurosci, 17, 2750-2754, 2003); Huntington disease (Sagredo et al. Glia, 57, 1154-1167 2009); Parkinson (Papa, S M. Exp. Neurol. 211, 334-338, 2008); Schizophrenia (Agid et al. Expert Opin Emerg Drugs., 13, 479-95, 2008). in liver diseasesin particular fibrogenesis associated with chronic liver diseases, ischaemia/reperfusion (I/R)-induced liver injury (Lotersztein et al., Brit. J. Pharmacol. 153, 286-289, 2008) and hepatic encephalopathy-associated with acute liver failure (Magen et al. Current Pharmaceutical Design. 14, 2362-2369, 2008), cerebral ischemic-reperfusion injury (Zhang et al., Neurosci. 152, 753-760, 2008); in cancer especially of hematopoietic origin (lymphoma and acute lymphocytic leukaemia), retinal vascularization, endometritis; appetite related disorders, metabolic syndrome, diabetes, and obesity. In some embodiments said disease or disorder is selected from inflammation, pain, allergies, neurological and neurodegenerative diseases, liver diseases, cerebral ischemic-reperfusion injury, cancer, retinal vascularization, endometritis, appetite related disorders, metabolic syndrome, diabetes, atherosclerosis and disorders related to anti-fibrinogenic effects and emesis or any combinations thereof.
In other embodiments a composition of the invention is for use in the stimulation of bone growth, bone mass, bone repair or prevention of bone loss.
In some other embodiments a composition of the invention is for the treatment of a disease or a disorder selected from osteopenia, osteoporosis, bone fracture or deficiency, primary or secondary hyperparathyroidism, osteoarthritis, periodontal disease or defect, an osteolytic bone loss disease, post-plastic surgery, post-orthopedic surgery, post oral surgery, post-orthopedic implantation, and post-dental implantation, primary and metastatic bone cancer and osteomyelitis, or any combinations thereof. In some embodiments said disease or disorder is selected from osteopenia and osteoporosis.
In a further aspect, the present invention provides a use of a composition of the invention, for the manufacture of a medicament for activating a CB receptor.
In yet a further aspect, the invention provides a use a composition of the invention, for the manufacture of a medicament for stimulation of bone growth, bone mass, bone repair or prevention of bone loss.
In another aspect, the invention provides a use a composition of the invention, for the manufacture of a medicament for the treatment of a disease or a disorder selected from osteopenia, osteoporosis, bone fracture or deficiency, primary or secondary hyperparathyroidism, osteoarthritis, periodontal disease or defect, an osteolytic bone loss disease, post-plastic surgery, post-orthopedic surgery, post oral surgery, post-orthopedic implantation, and post-dental implantation, primary and metastatic bone cancer, osteomyelitis, or any combinations thereof.
In a further aspect, the invention provides a method for activating a CB receptor in a subject in need thereof, said method comprising administering to said subject a therapeutically effective amount of a composition of the invention.
In yet a further aspect the invention provides a method of stimulation of bone growth, bone mass, bone repair or prevention of bone loss, said method comprising administering to a subject in need thereof a therapeutically effective amount of a composition of the invention.
The term “treatment” as used herein refers to the administering of a therapeutic amount of the composition of the present invention which is effective to ameliorate undesired symptoms associated with a disease, to prevent the manifestation of such symptoms before they occur, to slow down the progression of the disease, slow down the deterioration of symptoms, to enhance the onset of remission period, slow down the irreversible damage caused in the progressive chronic stage of the disease, to delay the onset of said progressive stage, to lessen the severity or cure the disease, to improve survival rate or more rapid recovery, or to prevent the disease form occurring or a combination of two or more of the above.
As used herein, the term “effective amount” means that amount of a composition of the invention that will elicit the biological or medical response of a tissue, system, animal or human that is being sought, for instance, by a researcher or clinician. The effective amount for purposes disclosed herein is determined by such considerations as may be known in the art. The amount must be effective to achieve the desired therapeutic effect as described above, depending, inter alia, on the type and severity of the disease to be treated and the treatment regime. The effective amount is typically determined in appropriately designed clinical trials (dose range studies) and the person versed in the art will know how to properly conduct such trials in order to determine the effective amount. As generally known, an effective amount depends on a variety of factors including the affinity of the ligand to the receptor, its distribution profile within the body, a variety of pharmacological parameters such as half life in the body, on undesired side effects, if any, on factors such as age and gender, etc. Furthermore, the term “therapeutically effective amount” means any amount which, as compared to a corresponding subject who has not received such amount, results in improved treatment, healing, prevention, or amelioration of a disease, disorder, or side effect, or a decrease in the rate of advancement of a disease or disorder. The term also includes within its scope amounts effective to enhance normal physiological function.
The invention further provides a composition comprising compound (1), said composition having a melting point of 44-45° C. and optical rotation of [α] D =−115°.
In a further aspect of the invention there is provided a method for preparing a compound of formula (II), said method comprising:
esterification of a compound of formula (V) with an acyl chloride to obtain compound (VI):
wherein acyl chloride may be any alkyl chloride for example pivaloyl chloride;
oxidation of compound (VI) to obtain 4-oxo-substituted compound (VII):
reduction of 4-oxo-substituted compound (VII) to the 4-hydroxy-substituted compound (VIII):
it is noted that such a reduction may give raise to both equatorial and axial hydroxyl substitution on position 4 of the bicyclic ring, with possible preference to the less sterically hindered substitution, such as for example the equatorial substitution.
condensation of 4-hydroxy-substituted compound (VIII) with compound (IX) to obtain condensed compound (X):
without wishing to be bound by theory this condensation will occur preferably at the equatorial position which is less sterically hindered due to the position of the dimethyl bridge.
reduction of ester group of condensed compound (X) to obtain compound of formula (II):
Such a reduction may also be obtained by hydrogenation of the ester group with agents such as for example LiAlH 4 to obtain the corresponding hydroxyl group. It is noted that the substituents R 2 , R 3 , R 6 , R 7 , and R 9 are all as defined herein above.
The present invention further concerns a method for the synthesis of HU-433, the method comprising:
1) esterification of (−) myrtenol [α] D =−51° with pivaloyl chloride in dry pyridine, thereby obtaining myrtenyl pivalate;
2) oxidation of myrtenyl pivalate with CrO 3 and tBuOOH in CH 3 CN to obtain the 4-oxomyrtenyl pivalate having m.p. 35° C., [α] D =−162°;
3) reduction of 4-oxomyrtenyl pivalate with NaBH 4 in ethanol to obtain 4-hydroxymyrtenyl pivalate;
4) condensation of 4-hydroxymyrtenyl pivalate with 5-dimethylheptyl-resorcinol (5-DMH-resorcinol), in the presence of pTSA, to obtain 2-(3-myrtenyl pivalate)-5-dimethylheptyl resorcinol;
5) methylation of 2-(3-myrtenyl pivalate)-5-dimethylheptyl resorcinol with methyl iodide and potassium carbonate to give 2-(3-myrtenyl pivalate)-5-dimethylheptyl dimethylresorcinol (HU-433 pivalate);
6) reaction of 2-(3-myrtenyl pivalate)-dimethylheptyl dimethyl resorcinol (HU-433 pivalate) with LiAlH 4 to yield the desired (−)-2-(3-myrtenyl)-5-dimethylheptyl resorcinol (HU-433), (−) isomer with m.p. 44-45° C., [α] D =−115°.
The present invention further concerns compounds obtainable by the above method.
It must be noted that, as used in this specification and the appended claims, the singular forms “a”, “an” and “the” include plural referents unless the content clearly dictates otherwise.
Throughout this specification and the claims which follow, unless the context requires otherwise, the word “comprise”, and variations such as “comprises” and “comprising”, should be understood to imply the inclusion of a stated integer or step or group of integers or steps but not the exclusion of any integer or step or group of integers and steps.
BRIEF DESCRIPTION OF THE DRAWINGS
In order to understand the invention and to see how it may be carried out in practice, embodiments will now be described, by way of non-limiting example only, with reference to the accompanying drawings, in which:
FIGS. 1A-1B shows column diagram describing the stimulation of MC3T3 E1 osteoblastic cell number by a compound of the present invention (i.e. HU-433) ( FIG. 1A ) and HU-308 ( FIG. 1B ) (shown as [cell per well]×10 −4 as a function of compound concentration (M). Data is mean±S.E. obtained in 3 culture wells per condition). ND, not done.
FIGS. 2A-2B shows column diagram describing the rescue of ovariectomy (OVX)-induced loss of trabecular bone volume density (BV/TV) by a compound of the present invention (i.e. HU-433) and HU-308. Treatment commenced 6 weeks after OVX, to allow initial bone loss, and consisted of 6-week intraperitoneal administration of: 0.2 mg/Kg/day HU-433 ( FIG. 2A ); 20 mg/Kg/day HU-308 ( FIG. 2B ). μCT analysis. Data are mean±S.E. obtained in 6 mice per condition. (*) p<0.05.
DETAILED DESCRIPTION OF EMBODIMENTS
The following Examples are representative of techniques employed by the inventors in carrying out aspects of the present invention. It should be appreciated that while these techniques are exemplary of preferred embodiments for the practice of the invention, those of skill in the art, in light of the present disclosure, will recognize that numerous modifications can be made without departing from the spirit and intended scope of the invention.
Example 1
Synthesis of HU-433
1. Preparation of Myrtenyl Pivalate
Pivaloyl chloride (8 g, 67 mmol) was added slowly to a solution of myrtenol (commercial myrtenol; Aldrich CAS#19894-97-4), [α] D =−51° (5 g, 33 mmol) in dry pyridine (25 ml), with cooling in ice bath. The mixture was stirred overnight at room temperature. Then the mixture was diluted with ether (25 ml) and ice water was added, the organic layer collected and washed with 10% HCl several times, then with NaHCO 3 , dried over Na 2 SO 4 and evaporated to give 7.17 g (91%) colorless oil.
2. Preparation of 4-Oxomyrtenyl Pivalate:
For the preparation of 4-oxomyrtenyl pivalate, CrO3 (1.06 g, 10.6 mmol) was dissolved in CH 3 CN (35 ml) and stirred at 0° C. Then t-BuOOH (17.5 ml 70%/H 2 O, 126 mmol) was added followed by the immediate addition of a solution of myrtenyl pivalate (5 g, 20 mmol) in CH 3 CN (38 ml). The reaction mixture was brought to room temperature and was stirred for 1 h. The reaction mixture was diluted with ether, and 10% Na 2 SO 3 in water (130 ml) was added. The mixture was extracted several times with ether, dried and evaporated. The crude mixture was purified by silica gel column chromatography (0-10% ether in petroleum ether) to give an oil that crystallized from pentane to give 4-oxo-myrtenyl pivalate (0.9 g, 19%) m.p. 35° C., [α] D =−162°.
3. Preparation of 4-Hydroxymyrtenyl Pivalate:
4-Oxo-myrtenyl pivalate (1 g, 4 mmol) was dissolved in ethanol (15 ml). NaBH 4 (0.2 g, 5.3 mmol) was added slowly and the resulting suspension was stirred at room temperature for 15 min. The ethanol was evaporated, then ether and water were added. The organic layer was separated, dried and evaporated to give a colorless oil (0.92 g, 91%).
4. Condensation of 4-Hydroxymyrtenyl Pivalate with DMH-Resorcinol:
To a solution of dry pTSA (0.16 g, 0.96 mmol) and 1,1-DMH-resorcinol (0.86 g, 3.44 mmol) in dry dichloromethane (125 ml) and under argon atmosphere, was added slowly a solution of 4-hydroxy-myrtenyl pivalate (0.88 g, 3.49 mmol) in dry dichloromethane (30 ml). The mixture was stirred at room temperature for 1.5 h. A saturated NaHCO 3 solution was added and the organic layer was then washed twice with water, dried and evaporated. The residue was purified by column chromatography on silica gel in ether/pet.ether (5:95) to give 0.71 g (43%) 2-(3-myrtenyl pivalate)-5-dimethylheptyl-resorcinol, a colorless oil.
5. Methylation:
Methyl iodide (0.75 ml, 12 mmol) was added to a solution of 2-(3-myrtenyl pivalate)-5-dimethylheptyl resorcinol (0.71 g, 1.51 mmol) and K 2 CO 3 (1.6 g, 12 mmol) in dry DMF (5 ml). After stirring at room temperature for 24 h, the mixture was diluted with water (40 ml) and extracted with ether. The organic layer was washed with water, dried and evaporated. Purification by column chromatography on silica gel with etherpetroleum ether (5:95) gave 0.51 g (67%) 2-(3-myrtenyl pivalate)-5-dimethylheptyl resorcinol (HU-433, pivalate) a colorless oil
6. Preparation of HU-433
HU-433 pivalate (0.35 g, 0.7 mmol) in dry ether (20 ml) was added slowly, under argon to a suspension of LiAlH4 (64 mg, 1.68 mmol) an dry ether (5 ml). The mixture was refluxed for 2 h. The excess LiAlH 4 was destroyed with ethyl acetate followed by a saturated solution of MgSO 4 until a clear ether solution was obtained. The ether layer was decanted, dried and evaporated. The product precipitated out from pentane to give HU-433, m.p. 44-45° C., [α] D =−115°
HU-433 spectral data: 1 H-NMR (CDCl 3 ): 3.741 (s, 6H CH3O—), 3.998 (t, J=2.1 Hz, 1H allylic), 4.069 (d, J=5.7 Hz, 2H, —CH2OH), 5.704 (t, J=1.2, 1H, olefinic) 6.483 (s, 2H, aromatic). MS calc/found: m/z 414.37/437.27 (m+Na).
Example 2
Binding Affinity of HU-433 Vs. HU-308 to CB1 and CB2 Cannabinoid Receptors
Binding of HU-308 to the CB1 and CB2 cannabinoid receptors was assayed (see Hanus et al, 1999), showing K i value of 22.7 nM. Binding of HU-433 was found to be significantly more potent, having K i value of 12.2 nM.
For CB1 receptor binding, synaptosomal membranes were prepared from the brains of Sabra rats by homogenization and gradient centrifugation (Devane et al, 1992). For CB2 receptor binding assay, COS-7 cells were transfected with plasmids containing CB2 cDNA, and crude membranes were prepared (Munro et al, 1993).
The high affinity receptor probe, [ 3 H]HU-243 (Tocris Cookson Ltd., United Kingdom), with a dissociation constant of 45±7 pM for the CB1 receptor, was incubated with synaptosomal membranes (3-4 μg) for CB1 assay or transfected cells for the CB2 assay, for 90 min at 30° C. with different concentrations of the assayed ligands or with the vehicle alone (fatty acid-free bovine serum albumin at a final concentration of 0.5 mg/ml).
Bound and free radioligands were separated by centrifugation. The data were normalized to 100% of specific binding, which was determined with 50 nM unlabeled HU-243.
Hanus et al., showed that HU-308 did not bind to CB1 receptor however showed potent binding to CB2 receptor (Table 1). In the present example it was shown that HU-433 did not bind to CB1 receptor. The binding of HU-433 to CB2 receptor was nearly twice more potent compared to HU-308 (Table 3).
TABLE 3
Binding of HU-433 and HU-308 to CB1 and CB2 receptors
Ki
Receptor
Ligand
CB1
CB2
HU-433
>20 μM
12.2 nM
HU-308
>10 μM
22.7 nM
Example 3
Comparative Skeletal Activity of HU-433 and HU-308
Osteoblastic MC3T3 E1 cells were cultured as reported in Miguel et al, 2005. For the last 46 hours in culture the cell were incubated with HU-433 or HU-308 added as a DMSO solution. Control cultures were treated only with the DMSO solvent (Ofek et al, 2006). In these cells, HU-433 and HU-308 doubled cell number at respective ligand concentrations of 10 −11 M and 10 −8 M, indicating that in the assay of HU-433 was a 1000-fold more active compared to HU-308 ( FIGS. 1A and 1B ). Typical of this assay system, the dose-response curves are bell shaped (Miguel et al, 2005), with the peak stimulation of cell number followed by reversal of the effect to baseline levels.
Based on the in vitro screening, the in vivo skeletal activity of HU-433 and HU-308 was analyzed in an ovariectomy (removal of ovaries; OVX) mouse model, the most widely used animal model for osteoporosis. Using this experimental system for testing bone anabolic activity, OVXed mice are left untreated to allow for bone loss to occur, followed by a treatment period intended for reversal of the bone loss (Alexander et al, 2001).
A micro-computed tomographic (μCT) analysis of L3 vertebrae indicated that HU-433, at 0.2 mg/Kg/day for 6 weeks significantly rescued almost the entire OVX-induced trabecular bone loss, whereas HU-308 reversed only 50% of the bone loss, and only at 20 mg/Kg/day for 6 weeks ( FIGS. 2A and 2B ). Thus, in vivo, HU-433 is at least 100-fold more active than HU-308 (at a 100 fold increase it only caused 50% of the HU-433 effect). The effect of HU-433 in above in vivo test system is substantially greater than the reversal of bone volumetric density by parathyroid hormone (1-34), the only clinically approved bone anabolic agent (Alexander et al, 2001). | Provided are compositions including (3R, 4R, 6R)-stereoisomers of phenyl substituted pinenes having CB receptor agonist properties, methods of treating diseases or disorders with the pharmaceutical compositions, and processes for their preparation are also provided. | 2 |
This application is a continuation application of U.S. patent application Ser. No. 10/725,588, filed Dec. 3, 2003 now U.S. Pat. No. 7,052,116, which is a divisional application of and claims priority from patent application Ser. No. 10/169,114, filed on Jun. 27, 2002, now U.S. Pat. No. 6,719,913 of the same title; and applicant herewith claims the benefit of priority of PCT/IT00/00534 filed on Dec. 19, 2000, which was published Under PCT Article 21(2) in English, and of Application No. AO99A00002 filed in Italy on Dec. 27, 1999.
TECHNICAL FIELD
This invention relates to a printhead used in equipment for forming, through successive scanning operations, black and colour images on a print medium, usually though not exclusively a sheet of paper, by means of the thermal type ink jet technology, and in particular to the head actuating assembly and the associated manufacturing process.
BACKGROUND ART
Depicted in FIG. 1 is an ink jet colour printer on which the main parts are labelled as follows: a fixed structure 41 , a scanning carriage 42 , an encoder 44 and, by way of example, printheads 40 which may be either monochromatic or colour, and variable in number.
The printer may be a stand-alone product, or be part of a photocopier, of a “plotter”, of a facsimile machine, of a machine for the reproduction of photographs and the like. The printing is effected on a physical medium 46 , normally consisting of a sheet of paper, or a sheet of plastic, fabric or similar.
Also shown in FIG. 1 are the axes of reference:
x axis: horizontal, i.e. parallel to the scanning direction of the carriage 42 ; y axis: vertical, i.e. parallel to the direction of motion of the medium 46 during the line feed function; z axis: perpendicular to the x and y axes: i.e. substantially parallel to the direction of emission of the droplets of ink.
The composition and general mode of operation of a printhead according to the thermal type technology, and of the “top-shooter” type in particular, i.e. those that emit the ink droplets in a direction perpendicular to the actuating assembly, are already widely known in the sector art, and will not therefore be discussed in detail herein, this description instead dwelling more fully on some only of the features of the heads and the manufacturing process, of relevance for the purposes of understanding this invention.
The current technological trend in ink jet printheads is to produce a large number of nozzles per head (≧300), a definition of more than 600 dpi (dpi=“dots per inch”), a high working frequency (≧10 kHz) and smaller droplets (≦10 pl) than those produced in earlier technologies.
Requirements such as these are especially important in colour printhead manufacture and make it necessary to produce actuators and hydraulic circuits of increasingly smaller dimensions, greater levels of precision, narrow assembly tolerances. It is important in particular to ensure that the volume and speed of the droplets subsequently emitted are as constant as possible, and that no “satellite” droplets are formed as these, with a trajectory generally different from the main droplets, are distributed randomly near the edges of the graphic symbols, reducing their sharpness.
FIG. 2 shows an enlarged axonometric view of an actuating assembly 111 of an ink jet printhead according to the known art, made of a die 100 of semiconductor material (usually Silicon), on the upper face of which resistors 27 have been made for emission of the droplets of ink, driving circuits 62 for driving the resistors 27 , soldering pads 77 for connecting the head to an electronic controller not shown in the figure, and which bears a pass-through slot 102 through which the ink flows from a reservoir not shown in the figure. Around the upper edge of the slot 102 a basin 76 has been made, the characteristics and functions of which are as described in detail in Italian patent application TO 98A 000562. Affixed to the upper face of the die is a layer 105 of photopolymer having, usually though not exclusively, a thickness less than or equal to 25 μm in which, by means of known photolithographic techniques, a plurality of ducts 53 and a plurality of chambers 57 positioned locally to the resistors 27 having been made. Stuck on the photopolymer 105 is a nozzle plate 106 , generally made of a plate of gold-plated nickel or kapton, of thickness less than or equal to 50 μm, bearing a plurality of nozzles 56 , each nozzle 56 being in correspondence with a chamber 57 . In the current technology, the nozzles 56 have a diameter D of between 10 and 60 μm, while their centres are usually spaced apart by a pitch A of 1/300 th or 1/600 th of an inch (84.6 μm or 42.3 μm). Generally, though not always, the nozzles 56 are arranged in two rows parallel to the y axis, staggered one from the other by a distance B=A/2, in order to double the resolution of the image in the direction parallel to the y axis; the resolution thus becomes 1/600 th or 1/1200 th of an inch (42.3 μm or 21.2 μm). The x, y and z axes, already defined in FIG. 1 , are also shown in FIG. 2 .
FIG. 3 is an axonometric enlargement of two chambers 57 , adjacent and communicating with the slot 102 through the basin 76 and the ducts 53 made in the layer of photopolymer 105 . Normally the ducts 53 have a length l and a rectangular cross-section having a depth a and a width b. The chambers 57 have a depth d, substantially equal to the depth a of the ducts 53 .
A section of an ejector 55 can be seen in FIG. 4 , where the following are shown, in addition to the items already mentioned: a reservoir 103 containing ink 142 , a droplet 51 of ink, a vapour bubble 65 , a meniscus 54 in correspondence with the surface of separation between the ink and the air, an external edge 66 and arrows 52 which indicate the prevalent direction of motion of the ink.
To describe the operation of an ejector for a thermal type ink jet printhead, an electrical analogy is used, for which the following equivalences are established:
V=electrical voltage in volt equivalent to: pressure in N/M 2 ;
I=current in A equivalent to: flow rate in m 3 /s;
R=resistance in ohm equivalent to: hydraulic resistance in
N/m 2 /m 3 /s=N s/m 5 ;
L=Inductance in henry equivalent to the ratio between the mass of the column of liquid that fills the duct and the square of the section of the duct; this ratio is called “hydraulic inertance”, and is measured in kg/m 4 ;
C=capacitance in farad equivalent to: hydraulic compliance
in m 3 /N/m 2 =m 5 /N.
In the equivalent diagram of FIG. 5 the bubble is represented as a variable capacitance C b . There is a front leg 70 , equivalent to the whole formed by the chamber 57 , the nozzle 56 , the meniscus 54 and the droplet 51 , and a rear leg 71 , which represents the section of the hydraulic circuit between the chamber 57 and the reservoir 103 .
The front leg 70 comprises a fixed impedance L f , R f corresponding substantially to the chamber 57 , a variable impedance L u , R u corresponding substantially to the nozzle 56 , and a deviator T which, during the step in which the droplet 51 is formed, inserts a variable resistance R g substantially corresponding to the droplet, whereas, during the steps of withdrawal of the meniscus 54 , of filling of the nozzle, of subsequent oscillation and damping of the meniscus, inserts a capacitance C m substantially corresponding to the meniscus itself.
Ejection of the ink takes places in accordance with the following steps:
a) The electronic control circuit 62 supplies energy to the resistor 27 , so as to produce local boiling of the ink with formation of the bubble 65 of steam in expansion. During this step, in the equivalent electric circuit of FIG. 5 the variable resistance R g is inserted. The bubble 65 generates two opposing flows: I p (to the reservoir 103 ) and I a (to the nozzle 56 ).
b) The electronic circuit 62 terminates the delivery of energy to the resistor 27 , the vapour condenses, the bubble 65 collapses, the droplet 51 detaches itself, the meniscus 54 withdraws emptying the nozzle 56 . The two opposing flows I p and I a remain. In this step, in the equivalent circuit of FIG. 5 the capacitance C m corresponding to the meniscus 54 is inserted.
c) The bubble 65 has disappeared, the meniscus 54 demonstrates its capillarity and goes back towards the outer edge 66 of the nozzle 56 sucking new ink 142 into the nozzle 56 . Its return completed, the meniscus 54 remains attached to the outer edge 66 by oscillating and behaving like a vibrating membrane. In the equivalent electric circuit of FIG. 5 the capacitance C m is still inserted. During this step the equivalent circuit of the ejector 55 is simplified as sketched in FIG. 6 , where C m represents the capacitance of the meniscus, while R and L represent respectively the sum of all the resistances and of all the inductances present between the meniscus 54 and the reservoir 103 . In addition, the flows I p and I a converge into a single flow i.
To obtain an optimal operation of the ejector 55 , it is necessary for the meniscus 54 , at the end of the step c), to reach the idle state rapidly and without oscillating. In this way the ink 142 does not wet the outer surface of the nozzle plate 106 , thereby avoiding alterations of speed and volume of the following droplets.
For a given nozzle 56 the parameters L u , R u and C m , belonging to the front hydraulic part 70 of the ejector 55 , are set and therefore, to obtain the values of R and L according to the criteria set down below, it is possible to act only on the design of the rear hydraulic part 71 .
The expression in function of the time i, which represents the flow, is given by the known relation:
i = V m L * t * ⅇ - t 2 τ ( 1 )
where V m represents the pressure generated by the meniscus 54 , which is negative during the filling step, and τ is the time constant, measured in seconds, of the RLC circuit of FIG. 6 , equal to the ratio L/R.
For maximum speed in filling of the nozzle 56 , the flow i must be rendered maximal, and for this to happen L and τ must be rendered minimal.
Also, for the meniscus 54 to reach the idle state rapidly without oscillating, the equivalent circuit of FIG. 6 must be “critical damping” type, and must for this purpose satisfy the known relation:
R
=
2
*
L
C
m
(
2
)
For a duct 53 of length l, the section of which has sides a and b with a >>b, the following known relations apply:
R ≅ 12 * ρ * v * l b 3 * a ( 3 ) L ≅ ρ * l b * a ( 4 ) τ = L R = b 2 12 * v ( 5 )
where ρ is the density of the ink in kg/m 3 , v is the viscosity of the ink in m 2 /s, and all lengths are measured in meters.
The time constant τ is a function of the width b, while it is independent of both the depth a and the length l.
It is possible to determine a value of b which gives values R and L such as to produce the critical damping, according to the expression (2). However the same value of b, substituted in (5), provides a value of τ which limits the flow i, according to the relation (1), and accordingly limits the emission frequency of the droplets. Moreover, it is not possible to modify either depth a or length l at will, as these parameters are subject to other technological and functional constraints, not described as they are not essential for the understanding of this invention.
To increase the emission frequency of the droplets, it is necessary to make the time constant τ much shorter than that obtained in the known art, while at the same time satisfying the critical damping condition: this problem is solved in this invention by making a plurality of N ducts in parallel, as will be seen in detail in the description of the preferred embodiment.
Some further drawbacks with the chambers 57 according to the known art are now mentioned, which have three continuous lateral walls and a fourth wall interrupted by the duct 53 of non-negligible width. In this situation the bubble 65 collapses prevalently in the direction of the resistor 27 underneath, which is thus subjected to greater wear on account of the known phenomenon of cavitation. In addition, the collapse of the bubble is dissymmetrical as it is attracted to the wall opposite the duct 53 : this cause a dissymmetry in the motion of the meniscus 54 , with a resulting deviation of the terminal part of the droplet 51 and the formation of satellite droplets having a different direction from the droplet 51 .
In this invention the duct 53 is substituted by N ducts placed in parallel and communicating with the chamber through the lower or upper wall, and consequently the four lateral walls of the chamber are continuous and symmetrical.
In U.S. Pat. No. 5,666,143 a solution is described in which the ink is brought to the chamber along multiple ducts, but these do not suffice to solve the problems reported.
DISCLOSURE OF THE INVENTION
It is an aspect of this invention to render the emission frequency of the droplets of ink maximal by making the time constant τ of the ejector as short as possible, while at the same time satisfying the condition of critical damping of the meniscus.
It is an aspect of an embodiment of the invention to increase the degrees of freedom of the design of the ejector, by having the additional parameter consisting of the number N of elementary ducts in parallel.
It is an aspect of an embodiment of the invention to increase the life span of the resistor by making a chamber with four continuous walls, which promotes symmetrical collapse of the bubble in the direction of these walls and not towards resistor: this lowers the harmful effects of cavitation during collapse of the bubble.
It is an aspect of an embodiment of the invention to avoid the formation of satellite droplets by achieving a symmetrical movement of the meniscus made possible by the chamber with four continuous walls.
It is an aspect of an embodiment of the invention to filter the ink of any impurities that may be present.
These and other objects, characteristics and advantages of the invention will be apparent from the description that follows of a preferred embodiment, provided purely by way of an illustrative, non-restrictive example, with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 —is an axonometric view of an ink jet printer;
FIG. 2 —is an enlarged view of an actuating assembly made according to the known art;
FIG. 3 —represents two emission chambers, according to the known art;
FIG. 4 —represents a sectioned view of one ejector of the head, according to the known art;
FIG. 5 —represents an equivalent electrical diagram of the hydraulic circuit of an ejector of the head;
FIG. 6 —represents a simplified equivalent wiring diagram of the hydraulic circuit of an ejector of the head;
FIG. 7 —represents an axonometric view of a portion of the actuating assembly of the head, made according to this invention;
FIG. 8 —represents an axonometric view of the emission chamber, according to a different visual angle from that of FIG. 7 ;
FIG. 9 —represents a section according to the plane AA, shown in FIG. 7 ;
FIG. 10 —illustrates the flow of the process for manufacture of the actuating assembly of FIG. 7 ;
FIG. 11 —represents a section view of the actuating assembly, at the start of the manufacturing process;
FIGS. from 12 to 14 —represent the actuating assembly as it is during later steps of the manufacturing process;
FIG. 15 —illustrates the flow of the manufacturing process of an actuating assembly according to a second embodiment;
FIG. 16 —represents an enlarged view of an actuating assembly, according to a third embodiment;
FIG. 17 —represents a section view and a view of the lower face of the actuating assembly, according to the third embodiment;
FIG. 18 —represents section view and a view of the lower face of the actuating assembly, according to a fourth embodiment;
FIG. 19 —represents an enlarged view of the actuating assembly, according to a fifth embodiment;
FIG. 20 —represents a section view of the actuating assembly, according to the fifth embodiment.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 7 illustrates a portion of the actuator for printhead, monochromatic or colour, comprising an ejector 73 according to the invention. For simplicity's sake, the other parts of the head, being already known and not concerning the invention, are not depicted. The following are shown in the figure:
a portion of a die 61 ;
a substrate 140 of Silicon P belonging to the die 61 ;
a slot 102 cut into the substrate 140 ;
the basin 76 , having depth c;
a layer 107 of photopolymer, according to the invention;
a chamber 74 according to the invention, made in the layer 107 of photopolymer, having depth d;
a bottom 67 of the chamber 74 ;
lateral walls 68 of the chamber 74 ;
the resistor 27 on the bottom 67 of the chamber 74 ;
elementary ducts 72 according to the invention, which convey the ink 142 from the basin 76 to the chamber 74 , each having depth f width g and length l.
FIG. 8 illustrates the chamber 74 from a different visual angle, indicated by the reference axes, which shows the outlet of the elementary ducts 72 in the chamber 74 . The ducts 72 are located under the layer 107 of photopolymer, and are therefore at a lower level than the bottom 67 of the chamber 74 : in this way, a tank 63 is made which hydraulically connects the ducts 72 with the chamber 74 .
FIG. 9 shows the ejector 73 sectioned according to a plane AA, indicated in FIGS. 7 and 8 .
According to a construction variant of the preferred embodiment, the basin 76 is missing, and the ducts 72 face directly on to the slot 102 .
A method is now described for calculating the correct number N of elementary ducts 72 .
The time constant τ is a function of the width g of each single duct 72 , whereas it is independent of the number N of ducts in parallel, as indicated by the following relation, analogous to (5):
τ
=
L
R
=
g
2
12
*
v
(
6
)
It is therefore possible to obtain as short a time constant τ as possible by selecting the smallest value of g possible, compatibly with technological feasibility.
Conversely, if we assign τ a predetermined value, we obtain:
g =√{square root over (12 *v*τ )} (7)
In practice, the width g according to this invention is, though not exclusively, between 3 and 15 μm.
Having thus determined the geometrical dimensions of a single duct 72 , we obtain values R′ and L′ of resistance and inductance equivalent to each duct 72 by means of the following relations, similar to (3) and (4):
R
′
≅
12
*
ρ
*
v
*
l
g
3
*
f
(
8
)
L
′
≅
ρ
*
l
g
*
f
(
9
)
The total resistance R and total inductance L of the equivalent circuit with the plurality of ducts 72 in parallel are calculated using the known formula for impedances in parallel, and are:
R=R′/N (10)
L=L′/N (11)
It is now possible to obtain the value of N by substituting the expressions (10) and (11) in (2), which becomes:
R ′ N = 2 * L ′ N * C m ( 12 )
and which allows us to obtain
N
=
(
R
′
)
2
*
C
m
4
L
′
(
13
)
The value thus obtained for N is generally not an integer, and must be rounded to the nearest whole number: this causes a slight deviation from the condition of critical damping, which may be recovered with a slight variation of the length l of the elementary duct 72 .
The manufacturing process of an ejector 73 for a monochromatic or colour ink jet printhead 40 according to the invention is effected according to the steps indicated in the flow diagram of FIG. 10 . FIGS. 11 to 14 represent the ejector 73 in successive stages of the work.
In the step 201 , by means of a known process, a wafer is made available containing a plurality of dice completed solely in the control circuits 62 and in the resistors 27 . Visible in FIG. 11 is a section of a portion of a die 61 in which an ejector will be made. The following are indicated:
a portion of the die 61 ;
the substrate 140 of Silicon P belonging to the die 61 ;
a LOCOS insulating layer 35 of SiO 2 ;
a BPSG “interlayer” 33 ;
the resister 27 ;
a layer 30 of Si 3 N 4 and SiC for protection of the resistors;
a conducting layer 26 , made of a layer of Tantalum covered by a layer of Gold.
In the step 202 , a photoresist is laid over the entire surface of the wafer.
In the step 203 , development is effected of the photoresist, by means of a first mask not depicted in any of the figures, of the geometry of the elementary ducts 72 , of the basin 76 and of the tank 63 .
In the step 204 , dry etching (Tegol) is performed of the LOCOS+BPSG+Si 3 N 4 until the substrate 140 of Silicon is uncovered in the areas defined by the first mask in the previous step 203 .
In the step 205 , the elementary ducts 72 , the basin 76 and the tank 63 are etched into the Silicon using “dry” technology in the STS plant, with arrangements known to those acquainted with the sector art. Geometry of the etching is defined by the photoresist already developed in the step 203 according to the design of the first mask, reinforced by the layer of LOCOS+BPSG+Si 3 N 4 beneath. Referring back to FIG. 7 , depth f of the channels is less than depth c of the basin 76 due to the different etching speed resultant on the different width of the etching front. If, as a non-restricting example, we assume f=10 μm, g=5 μm and a basin width of 300 μm, we obtain a depth c of the basin equal to approximately 20 μm. In general, the depth f is prevalently but not exclusively between 10 and 100 μm. At this stage of the work, the ejector is as shown in FIG. 12 .
In the step 212 , the photoresist is removed and the wafer cleaned.
In the step 213 , the layer 107 , consisting of negative photopolymer, is laminated on the entire surface of the wafer.
In the step 214 , the layer 107 is developed according to the geometry of a second mask, non depicted in any of the figures, with the purpose of obtaining the chamber 74 , the plan of which includes the resistor 27 and the tank 63 , and uncovering the basin 76 , as illustrated in FIG. 13 , where the dashed area represents the remaining photopolymer.
In the step 215 , the areas of the resistors 27 and of the soldering pads 77 are protected using a material that may be removed with water.
In the step 216 , the pass-through slot 102 is made by way of, for example, a sand blasting process. At this stage of the work, the zone of the ejector is as shown in FIG. 14 .
In the step 217 , the usual completion and finishing operations are carried out, known to those acquainted with the sector art.
Second Embodiment
The principle of the invention is also applicable in cases where the basin 76 is made with a ratio between the depth c and the depth f of the elementary ducts 72 and of the tank 63 that is greater than what it would be naturally on account of the different etching speeds. As a non-restricting example, for the basin 76 a depth c of between 20 and 100 μm may be selected, and for the ducts 72 and the tank 63 a depth f of between 5 and 20 μm. The production process is modified according to the flow diagram of FIG. 15 , in which the following steps are inserted after the step 204 .
In the step 205 ′, elementary ducts 72 and the tank 63 are etched into the Silicon with “dry” technology on the STS plant. The depth f of the etching is prevalently but not exclusively limited to between 5 and 20 μm. In this stage, the basin 76 may or may not be etched, depending on the design of the first mask.
In the step 206 , the photoresist previously laid in the step 202 and developed in the 203 is removed.
In the step 207 , lamination is performed of a “dry film” type photoresist over the entire surface of the wafer, which in this way covers and protects the area occupied by the\ducts 72 and the tank 63 .
In the step 210 , development is effected of the second photoresist, by means of a third mask not depicted in any of the figures, so as to leave uncovered only the area of the basin 76 .
In the step 211 , a further etching is made in the Silicon, this time of the basin 76 , using “dry” technology in the STS plant. The depth of this etching is in this way greater than that which would be obtained by the step 205 ′ alone, and prevalently but not exclusively between 20 and 100 μm.
Once this step is completed, the process continues to step 212 , as already described for the preferred embodiment.
Third Embodiment
A variant in the known art consists in producing the nozzles directly on a “flat cable”, which in this way also performs the function of nozzle plate, and is represented in FIG. 16 by means of an enlarged view of an actuating assembly 112 . According to this embodiment, the nozzle plate 106 is replaced by a flat cable with nozzles 130 , which comprises the nozzles 56 ′. The following may be seen in the figure:
the die 100 , made according to the known art already illustrated in FIG. 2 ;
the layer of photopolymer 107 , made according to the preferred embodiment, which comprises the chambers 74 having the continuous lateral walls 68 ;
the flat cable with nozzles 130 , made for instance of Kapton;
an upper face 113 of the flat cable with nozzles 130 ;
a lower face 114 of the flat cable with nozzles 130 .
FIG. 17 presents a section of the flat cable with nozzles 130 and a view of its lower face 114 , limited to a single ejector. The elementary ducts 72 ′ are made directly on the lower face 114 of the flat cable with nozzles 130 , using for instance an excimer laser.
Fourth Embodiment
This embodiment is represented in FIG. 18 by way of a section of the flat cable with nozzles 130 and a view of the lower face 114 , limited to a single ejector. The elementary ducts 72 ′ are again made directly on the lower face 114 of the flat cable with nozzles 130 , together with a chamber 74 ′, using for instance an excimer laser, but the layer 107 is missing.
Fifth Embodiment
The principle of the invention is also applicable in cases where the feeding of the ink takes place on the two sides of the die, according to a variant of the known art disclosed in the U.S. Pat. No. 5,278,584. FIG. 19 represents a die 183 with lateral feeding of the ink and a flat cable with nozzles 180 associated therewith, having an upper face 115 and a lower face 116 , produced according to said patent.
FIG. 20 represents a section view of a die with lateral feeding 183 ″, of a photopolymer 107 ″ in which a plurality of chambers 74 ″ has been made, of a flat cable with nozzles 180 ″ which present an upper face 115 and a lower face 116 . A plurality of nozzles 56 ″ and elementary ducts 72 ″ are made in the lower face 116 of the flat cable with nozzles 180 ″, similarly to what was described in the third embodiment. The ink reaches the chamber 74 ″ from the sides of the dice 183 ″ through the elementary ducts 72 ″.
A variant of the fifth embodiment may be obtained by also etching the chambers directly in the lower face 116 of the flat cable with nozzles 180 ″ and eliminating the layer of photopolymer 107 ″, similarly to what was described for the fourth embodiment.
A further variant of the fifth embodiment may be obtained by etching the elementary ducts in the silicon of the dice 183 , on a plane below the layer 107 ″, similarly to what was described for the preferred embodiment. The elementary ducts face on to a depression produced by a “scribing” operation, known to those acquainted with the sector art: in this way, the cut with the diamond wheel, which separates the dice 183 , does not touch the ends of the elementary ducts directly, and thus avoids damaging them. | A thermal ink jet printhead ( 40 ) for the emission of droplets of ink on a print medium ( 46 ) comprises a reservoir ( 103 ) containing ink ( 142 ), a die ( 61 ), a slot ( 102 ) engraved in said die ( 61 ) and a plurality of ejectors ( 73 ), each of which in turn comprises a chamber ( 74 ), a resistor ( 27 ) and a nozzle ( 56 ), each of said chambers ( 74 ) being put in fluid communication with said slot ( 102 ) through a plurality of elementary ducts ( 72 ) lying on a different plane from the bottom ( 67 ) of said chamber ( 74 ). | 1 |
BACKGROUND OF THE INVENTION
This invention relates to flame-and smoke-retardant rigid polyurethane foam, and more particularly to 2-trichloromethyl-1, 3-oxazolidine, 2-trichloromethyl-1, 3-thiazolidine and derivatives thereof which are especially useful in retarding smoke and flames in rigid polyurethane foams.
Rigid polyurethane foams are becoming increasingly important as an insulation material in construction of new buildings to reduce energy losses. Building code regulations now require that these foams be not only flame retardant but also have low-smoke properties in order to make escape exits more easily observable by the occupants and to allow easy access by firemen. The prior art discloses the use of chlorinated compounds as flame retardants such as trichlorobutylene oxide for rigid polyurethane foam but these compounds have the disadvantage of generating too much smoke on combustion of the foam. (See U.S. Pat. No. 3,741,921). The flame and smoke retardants of this invention overcome the disadvantages of the prior art because they generate less smoke on combustion.
STATEMENT OF THE INVENTION
The present invention is directed to a rigid polyurethane foam prepared from a reaction mixture which comprises a smoke and flame retarding amount of a compound selected from the group consisting of ##STR1## where (a) X is O or S; and
(b) R is selected from the group consisting of H, ##STR2##
DETAILED DESCRIPTION OF THE INVENTION
A variety of rigid polyurethanes can be used in this invention. Some typical examples are described in E. N. Doyle "The Development and Use of Polyurethane Products." McGraw Hill Book Company, New York, 1971, and in W. C. Kuryla and A. J. Papa "Flame Retardancy of Polymers Materials" Volume 3, Marcel Dekker, Inc., New York, 1975; these references are hereby incorporated herein and should be considered as a part of this disclosure. In general, the flame-and smoke-retardant rigid polyurethanes are prepared by adding 1 to 30 parts by weight of the retardant to the reactants, i.e., polyols, surfactants, catalyst, water, blowing agents, and isocyanate, to produce the rigid polyurethane foam.
The preferred flame retardants for use in the instant invention are 2-trichloromethyl-1, 3-oxazolidine, 2-trichloromethyl-1, 3-thiazolidine, 3-(2-hydroxyethyl)-2-trichloromethyl-1, 3-thiazolidine, 3-(2-hydroxyethyl)-2-trichloromethyl-1, 3-oxazolidine, 3-(2-hydroxypropyl)-2-trichloromethyl-1, 3-oxazolidine, and 3-(2,3-dihydroxypropyl)-2-trichloromethyl-1, 3-oxazolidine.
In the following examples the foams are prepared by mixing the ingredients and adding the mix to a mold of the dimensions 8×8×5 inches. The foam is first aged for 7 days and then cut into 3×3×1-inch specimens that are burned in the NBS Smoke Chamber using the flaming mold in accordance with ASTM special technical publication 422 (1969) and NFPA 258-T "Smoke Generated by Solid Materials" May, 1974. Flame retardancy was measured by ASTM D-1692 test which involves burning a 2×5×1/2-inch sample horizontally in a draft-free hood with a propane flame. Samples burning the entire length are not considered flame-retarded. The values are reported in inches burned. The average of two or more values is reported.
The following examples merely illustrate the present invention but are not intended to limit the invention thereto.
EXAMPLE 1
2-Trichloromethyl-1, 3-oxazolidine
To a 2 liter 3-necked flask equipped with a stirrer, Dean-Stark trap, a condenser and dropping funnel were added 214 g (3.51 moles) ethanolamine and 450 g. toluene. Then 273 g (4.55 moles) of glacial acetic acid were added slowly to keep the temperature (cooling if necessary) at 30°-45° C. Then 568 g (3.85 moles) of chloral were added at 40°-50° C. The reaction mixture was refluxed to remove water and, when complete, the temperature increased to 115°-120° C. The reaction mixture was cooled in an ice bath and the product precipitated after standing for several hours to give 189.5 g (28.5%) m.p. 72°-74° C. The filtrate was washed with 5.0 moles of 20% sodium hydroxide and more product precipitated. Filtration and drying yielded 228.5 g (34.3%), m.p. 73°-75° C. The toluene layer was washed with water and evaporated to give a solid. Washing with water and filtration yielded upon drying 328 g. (49.2%), m.p. 62°-72° C. for a total yield of 556.0 g (83.5%). The analysis was consistent with the assigned structure.
The composition of Example 1 may be reacted with epichlorohydrin or other oxiranes (ethylene oxide, propylene oxide) to give the hydroxy containing derivatives of this invention which are useful as flame retardants.
EXAMPLE 2
3-(2-Hydroxyethyl)-2-Trichloromethyl-1, 3-Oxazolidine
One mole of the composition of Example 1 was reacted with 1.1 moles of ethylene oxide under pressure to give 3-(2-hydroxyethyl)-2-trichloromethyl-1, 3-oxazolidine which analyzed well for the assigned structure. The analogous thiazolidine compound is prepared in a similar manner.
______________________________________Examples 3-5Foam Formulation: Parts______________________________________Polyol (Poly G-71-530 Olin) 100.0Surfactant (DC-193-Dow Corning) 1.5Water 0.5Catalyst (Penncat 283-Pennwalt) 3.0Blowing Agent (Pennwalt's Isotron-11) 50.0Flame Retardant as shownPolyisocyanate (PAPI-UpJohn) as shown______________________________________ Ex. 3 Ex. 4 Ex. 5______________________________________Flame Retardant (php).sup.a none Thermolin RF230.sup.b Comp. (25) of Ex. 1 (22)PAPI (parts by wt.) 153 140 153NBS-MaximumSmoke Density (corrected) 138 166 127ASTM D-1692(inches of burn) 2.0 1.25 0.78______________________________________ .sup.a php = parts per hundred parts of polyol. .sup.b a trademark for trichlorobutylene oxide polyol marketed by Olin Corporation.
Examples 3-5 show in a comparison that when no flame retardant is used the foam strip burns completely (Example 3); when a prior art composition is used (Example 4), the inches of burning are only slightly less than the control; and when the composition of this invention is used (Example 5), the inches burned are substantially reduced. Furthermore, note that the maximum smoke density for Example 5 is also significantly less than in Examples 3 and 4.
EXAMPLE 6
To the formulation shown in Examples 3-5 was added 22.5 php of 3-phenylsulfonyl-2-trichloromethyl-1, 3-oxazolidine. The sample burned the entire length in the ASTM D 1692 test and the smoke density was similar to that of Example 5. This example demonstrates that not all oxazolidines give acceptable flame retardancy rating nor come within the scope of this invention.
EXAMPLE 7
To the formulation shown in Examples 3-5 was added 17 php of 3-formyl-2-trichloromethyl-1, 3-oxazolidine. The sample burned the entire length in the ASTM D 1692 test and the smoke density was similar to that of Example 5. This is another substituted oxazolidine not within the scope of this invention that does not produce acceptable flame retardancy rating.
EXAMPLE 8
To the formulation in Examples 3-5 was added 30 php of 3-(2-hydroxyethyl)-2-trichloromethyl-1, 3-oxazolidine (Example 2) followed later by 171 parts PAPI. The flame and smoke density results were equivalent to Example 5.
EXAMPLE 9
3-(2-Hydroxypropyl)-2-Trichloromethyl-1, 3-Oxazolidine
To a three-necked flask equipped with a mechanical stirrer, Dry Ice condenser, addition funnel and thermometer were charged 191 g (1.0 mole) of 2-trichloromethyloxazolidine, 400 g. toluene and 1 ml of triethylamine. Then 64 g (1.1 mole) of propylene oxide was added and the temperature raised to 55° C. The reaction was over when the propylene oxide stopped refluxing. The reaction mixture was then concentrated under reduced pressure to yield the product. The analysis was consistent with the assigned structure. The analogous thiazolidine is prepared in a similar manner.
EXAMPLE 10
To the formulation in Examples 3-5 was added 31 php of 3-(2-hydroxypropyl)-2-trichloromethyl-1, 3-oxazolidine (Example 9) followed later by 171 parts PAPI. The flame and smoke density results were equivalent to that of Example 5.
EXAMPLE 11
3-(2,3-Dihydroxypropyl)-2-Trichloromethyl-1,3-Oxazolidine
To a three-necked flask equipped with a mechanical stirrer, condenser, addition funnel and thermometer were charged 191 g (1.0 mole) of 2-trichloromethyloxazolidine, 101 g (1.0 mole) of triethylamine and 400 g of tetrahydrofuran. Then 93 g (1.0 mole) of epichlorohydrin was slowly added while heating the reaction mixture to 66° C. After the reaction was complete, the precipitate of triethylamine hydrochloride was filtered and the filtrate added to a flask containing 100 ml of 10% aqueous triethylamine solution. The reaction mixture was gently refluxed for 3 hours and the product isolated by removing the volatiles under reduced pressure. The analysis was consistent with the assigned structure. The analogous thiazolidine is prepared in a similar manner.
EXAMPLE 12
To the formulation in Examples 3-5 was added 35 php of 3-(2,3-dihydroxypropyl)-2-trichloromethyl-1, 3-oxazolidine (Example 11) followed later by 174 parts PAPI. The flame and smoke density results were equivalent to that of Example 5.
EXAMPLE 13
To the formulation in Examples 3-5 was added 24 php of 2-trichloromethyl-1, 3-thiazolidine followed later by 153 parts PAPI. The flame and smoke density results were equivalent to that of Example 5. | A rigid polyurethane foam is prepared from a reaction mixture incorporating therein a 2-trichloromethyloxazolidine or a thiazolidine derivative for imparting to the foam smoke and flame retardancy. | 2 |
FIELD OF THE INVENTION
This invention pertains to the reduction or elimination of undesirable shunt currents in electrochemical devices such as battery systems, and, more particularly, to an improved protective electrode in an electrochemical device for applying nulling voltages to reduce or eliminate the shunt currents.
BACKGROUND OF THE INVENTION
In electrochemical devices of all kinds, and, in particular, those battery systems having a plurality of cells immersed in a common electrolyte, shunt current losses are known to result from conductive current bypass paths which occur in the electrolyte surrounding the cells. Such shunt current losses are always present in these devices during charging, discharging and under open circuit conditions, and have undesirable side effects leading to the shortening of their useful life.
In a patent application assigned to a common assignee, by M. Zahn, P. G. Grimes, and R. J. Bellows, entitled, "SHUNT CURRENT ELIMINATION AND DEVICE", Ser. No. 939,325, filed Sept. 5, 1978, now U.S. Pat. No. 4,197,167, a method for eliminating shunt currents is described wherein a protective nulling current is applied through the common electrolyte disposed in a common manifold. The present invention is based upon the teachings set forth in the above-mentioned application, and is meant to incorporate these teachings herein by way of reference.
In the course of applying these protective currents, particularly in systems featuring circulating electrolyte, electrodes are required which would not block or impede the flow of electrolyte through the manifold system. One of the simplest and most effective electrode designs from a hydraulic point of view is a thin wire electrode disposed in the center of the flow stream. These electrodes prevent substantial pressure drops. This type of electrode applies the current at a point of focused source, and, therefore, provides a non-uniform current density profile in the manifold in the proximity of the electrode, which current density eventually spreads along the length of the manifold. Devices which show a point source or focused current electrode structure are to be seen in the patents to P. Durand, entitled "ELECTROCHEMICAL GENERATORS WITH AUXILIARY CATHODE", U.S. Pat. No. 4,136,232, issued Jan. 23, 1979, and J. Jacquelin, entitled "FORCED FLOW ELECTROCHEMICAL BATTERY", U.S. Pat. No. 4,081,585, issued Mar. 28, 1978.
The Jacquelin and Durand electrodes are constructed in this fashion in order to generate finite amounts of zinc metal, which are easily washed away in the electrolyte stream. The non-uniformity of the current density with the use of a point source electrode along the manifold will produce a voltage drop at each cell position which does not equal the shunt voltage. The shunt currents would, therefore, not be effectively reduced using these electrodes.
The invention first contemplated the use of a screen or mesh type electrode for allowing a generally unimpeded fluid flow, while also providing a substantially uniform current density to be applied throughout the manifold. While such an electrode structure would work well in some cases, it was impractical where the electrode would be required to supply reactants to the electrolyte solution, or remove certain undesirable products therefrom. For example, in an electrolysis cell, the need to remove oxygen build-up in the hydrogen production electrolyte is desirable to prevent the possibility of an explosion. Also, in certain situations, the pressure drop in the fluid caused by screens is undesirable.
After careful assessment of all the feasible electrode designs, the use of an annular-type of electrode was deemed to be the most practical. The annular electrode does not impede or block fluid flow in those systems or parts of systems using circulating electrolyte, and at the same time will allow for the application of a protective current about the manifold which provides a substantially uniform current density profile through the electrolyte along the manifold.
In addition, the annular electrode can be provided with means to inject or remove its reactants and/or its products from the electrolyte.
As a further advantage of applying a protective current about the manifold, which current has a uniform current density profile, there is a reduction of the power required to maintain the nulling current.
The reduction in power consumption with the use of an annular electrode structure is made possible by the fact that other electrode designs require that the electrodes be placed at a greater distance along the manifold from the individual current producing cells. This greater distance is necessary to allow the lines of current from the point source to radially spread-out into the manifold, so as to provide a proper nulling match with the shunt voltage at each cell position. Because the currents have to travel through a greater electrolyte distance with the use of a point source electrode, a greater voltage boost or power consumption is required for these point or focused electrode designs. Annular electrodes which put forth a substantially uniform pattern of current lines in the manifold can be placed closer to the cells, thus requiring less power.
In addition, since impressed electrode voltage is also a function of current density, the design of electrodes with a greater surface area, as available with annular electrode designs, is also desirable from a current density and power standpoint.
BRIEF DESCRIPTION OF THE INVENTION
The present invention is directed to an electrochemical device comprising at least one common manifold fluidically communicating with a plurality of series connected cells. The manifold carries the electrolyte which provides an electrical electrolytic conductive bypass path around the cells. This bypass path is capable of resulting in undesirable shunt currents.
At least one annular protective electrode which is supported by the manifold applies a protective current about the manifold which has a substantially uniform current density profile through the electrolyte along the manifold. This uniform current density profile will effectively reduce or eliminate shunt currents while minimizing the power consumed to do so.
With respect to the above description of the invention, it is meant by "annular electrode", all those electrode designs or structures having a generally surrounding radial cross-section with respect to the manifold, such as a circular, oval, or polygonal inner wall cross-section. In addition, the annular electrode may have an axial cross-sectional shape which is straight, curved, tapered, or irregular. The use of different design shapes befits the required need for contouring the flow of electrolyte and contouring the current density profile to suit the intended purpose. However, the circular radial cross-section, and the tapered axial cross-section is probably the preferred design.
As used above, the term "uniform current density profile" is meant to imply protective current lines which are substantially uniformly spread throughout the cross-section of the electrolyte fluid for substantially the entire length of the manifold, such that the voltage drop opposite each cell is substantially equal to the shunt voltage for that cell position.
As used above, the term electrochemical device may be one of the following: a photoelectrochemical device, a battery (primary or secondary), a fuel cell, a chlor-alkali cell, an electrowinning device, an electrorefining device, an electrolyzer, an electrochemical reactor, a monopolar or bipolar device, and a device having circulating or non-circulating electrolyte(s).
As used herein, the term "common electrolyte" shall mean an electrolyte which is employed in and distributed to two or more cells, the electrolyte comprising a physical continuum. In a circulating electrolyte system using one or more manifolds, the physical continuum includes the electrolyte contained within the manifolds, the branch channels and the cells. In a static electrolyte system, the physical continuum includes the electrolyte in the cells and the connecting areas of electrolyte, e.g., above or around the cells.
As used herein, the term "shared electrolyte" shall mean that portion of the electrolyte which is located in an area of commonality to the electrolyte contained in individual components. Thus, in a circulating electrolyte system using one or more manifolds, the electrolyte contained within manifold(s) is the shared electrolyte and electrolyte contained in branch channels, cells and other individual components is not shared electrolyte. In a static electrolyte system, the shared electrolyte is that electrolyte contained in the header space and/or common base areas of the device and not that electrolyte contained within each cell and within other individual components.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a schematic view of an electrochemical device having a series connected stack of eight monopolar cells and four common manifolds each having two annular electrodes of this invention;
FIG. 2 depicts a perspective cut-away view of a negative protective annular electrode of this invention disposed adjacent one of the common manifolds in FIG. 1;
FIGS. 3a through 3d show various (but not all) possible radial cross-sectional designs for the annular electrodes of FIG. 1; and
FIGS. 4a through 4c illustrate various (but not all) possible axial cross-sectional designs for the annular electrodes of FIG. 1.
DETAILED DESCRIPTION OF THE INVENTION
The present invention involves a device utilizing the application by an annular electrode of a protective current through an electrical electrolytic conductive bypass path in an operating electrochemical device. The device has a plurality of cells connected, at least in part, in series, and having an electrolyte which is a common electrolyte to at least two such cells and which includes shared electrolyte, whereby an electrical electrolytic conductive bypass path is created around these cells and through said shared electrolyte, resulting in undesirable shunt currents in the absence of said protective current.
Shunt current minimization via a protective current applied by annular electrodes can be employed with an electrochemical device having non-circulating electrolyte(s). The electrolyte can be static, or at least for some time is not being transported or circulated, and this electrolyte is common, i.e., is of a physical continum, to at least two of the cells in series whereby an electrical electrolytic conductive bypass path is created through the electrolyte around the cells having the common electrolyte, resulting in undesirable shunt currents. The conductive bypass path includes shared electrolyte and it may be located at an electrolyte level above the cells, or it may be located through an independent common structural entity such as a base, a fill well or a fill manifold. In any event, the means for applying the protective current constitutes annular electrodes placed at each end of the path in the electrolyte externally from the cells and within the shared electrolyte. The application of the protective current through the path will effectively minimize the shunt currents.
In a preferred embodiment of the present invention, such as illustrated in FIG. 1, the device involves a circulating electrolyte(s) whereby circulation through the device is achieved by one or more manifolds having a circulating common electrolyte, including shared electrolyte, through which the electrical electrolytic conductive bypass path is created, resulting in shunt currents. Annular electrodes are provided for the application of a protective current through one or more manifolds, i.e., through the shared electrolyte portion of the conductive bypass path, to minimize the shunt currents. The protective current provided by the annular electrodes has a substantially uniform density through the shared electrolyte in the manifold(s) and thus acts to minimize the production of shunt currents with a minimum of consumed power through the manifold(s) and through the branch channels connecting the cells to the manifold(s). There is, thus, a conversion from electronic current to electrolytic current. Oxidization/reduction reactions at these electrodes convert the electronic current to an ionic current. Thus, at least in principle, any redox reactions may be used. For example, they could be the same as the reactions at the electrodes of the electrochemical device. Alternatively, other reactions may be used which are compatible chemically and electrically with the electrochemical device.
For example, H 2 could be anodically oxidized at one end of the electrochemical device and H 2 could be evolved at the other end. The two reactions in acidic solution would be
H.sub.2 →2H.sup.+ +2e (anodic)
and
2H.sup.+ +2e→H.sub.2 (cathodic)
The H 2 gas produced could be piped back to the anodic electrode.
In another case, bromide could be oxidized at one electrode and bromine reduced at the other:
2Br.sup.- →Br.sub.2 +2e
2e+Br.sub.2 →2Br.sup.-
In another case, O 2 could be oxidized at the anode and reduced at the cathode:
O.sub.2 +4H.sup.+ +4e→2H.sub.2 O
2H.sub.2 O→O.sub.2 +4H.sup.+ +4e
The choice of the redox reactions is dependent on the particular system being protected and could follow standard electrochemistry, as a matter of choice.
It should be noted that the electrochemical device described herein is one in its simplest terms which has a plurality of cells connected, at least in part, in series. However, an electrochemical device of the present invention may be just that or may, on a larger scale, consist of two or more blocks of cells connected electrically in series and have common electrolyte(s) supplied to and removed from the blocks in parallel from major manifolds. Each block of cells may consist of two or more cells in series, with these cells being supplied with electrolyte in parallel from submanifolds in the block of cells. Such systems would have shunt currents within the blocks through the block manifolds and would have shunt currents between the blocks of cells through the main manifolds. These can be minimized with protective currents in the block manifolds an in the main manifolds, as desired.
The application of protective currents through manifolds in general requires the use of two electrodes, one positive and one negative, for electrochemical reactions to insert the current. Factors to be considered are:
Where the reactants are not available (in sufficient quantity) in the electrolyte disposed in the manifold, they must be supplied from an external source. Where the products of the reactions at the protective electrodes are undesirable with respect to the electrolyte, they must be removed.
The annular protective electrodes can be constructed with a liner as will be discussed hereinafter in more detail, which liner allows the ancillary supplying of needed reactants and/or the removal of undesirable products.
The annular protective electrodes illustrated in FIG. 1 as electrodes 52, 52', 54, 56, and 58 may be respectively of both types, as will be explained.
A protective current was employed in accordance with the present invention by means of annular electrodes in conjunction with a stack of series connected zinc-bromine monopolar cells, shown schematically in FIG. 1. In FIG. 1, protective electrodes 52, 56, 54', 58' are disposed within the main electrolyte flow of the system and are of annular construction. Protective electrodes 54, 58, 52', 56' could be planar, i.e., they are not involved in the hydraulics of the system. However, thermal and product considerations may dictate that a flow of electrolyte(s) through these protective electrodes would be desirable. In such a situation, an annular construction could also be used.
This battery device having a series connected stack of eight cells is illustrated generally as 10. Cell 12 is representative of the cells and contains anode electrode 14 and cathode electrode 16. Anolyte flows (arrow 11) into cell 12 at compartment 18 via channel 20, and catholyte flows (arrow 13) into cell 12 at compartment 22 via channel 24. Compartment 18 and compartment 22 are divided by ionically permeable membrane separator 26. Cell 12 is connected in series to the next adjacent cell 28 via electrical connection 30. End cells 12 and 12' contain end terminals 34 and 36, respectively. The anolyte flowing into compartment 18 via channel 20 does so via shared electrolyte manifold 38, which feeds anolyte to all of the cells. The anolyte exits (arrow 15) compartment 18 via channel 40, and through shared electrolyte manifold 42, through which all anolyte exits. The catholyte flowing into compartment 22 via channel 24 does so via shared electrolyte manifold 44, which feeds catholyte to all of the cells. The catholyte exits (arrow 17) compartment 22 via channel 46, and through shared electrolyte manifold 48, through which all catholyte exits.
Annular electrodes 52, 52', 54, 54', 56, 56', 58 and 58' for providing protective currents to this device 10 are typically located on each end of the four manifolds 38, 42, 44 and 48, respectively, and are in contact with the shared electrolyte. Anolyte manifolds 48 and 42 have protective current negative electrodes 52 and 52', respectively, and protective current positive electrodes 54 and 54', respectively. Catholyte manifolds 44 and 48 have protective current negative electrodes 56 and 56', respectively, and positive electrodes 58 and 58', respectively. By way of example, a protective current is applied between negative electrode 52 and positive electrode 54 to effect the protective current through the shared electrolyte across manifold 38, thereby nulling or minimizing shunt currents passing through the conductive bypass path, i.e., passing from the channels connected with manifold 38 and otherwise passing therethrough. Similarly, protective currents are applied across manifolds 42, 44 and 48 through the shared electrolyte.
Both the anolyte and the catholyte are circulated through their respective manifolds, channels and compartments during operation of the device and are recirculated from reservoirs (not shown). As illustrated, the monopolar cells in device 10 are connected electrically in series and hydraulically in parallel. Without application of the protective currents of the present invention, significant shunt currents arise in the channels and manifolds. In this zinc-bromine device, the shunting not only results in loss of capacity and consumption of components, but also causes the growth of zinc at various points on the electrode near where the anolyte leaves and enters zinc electrode compartments.
The positive protective annular electrodes 54, 54', 58 and 58' in the zinc-bromine system illustrated in FIG. 1 may each comprise a carbon and/or graphite annular sleeve. Electrolytes will flow (arrows 19 and 21) directly through annular electrode sleeves 54' and 58' in respective manifolds 42 and 48. The typical sleeve surface 58' is sufficiently corrosion resistant to oxidize Br - to Br 2 over long periods of time. Current collection can be achieved via a tantalum wire current collector 64. In other systems, the wire current collector 64 can be made from other materials such as platinum or carbon, which materials may be more compatible with the particular reaction of the device. Similarly, the positive protective electrode sleeve 58' may comprise other, more compatible materials in different electrochemical reaction devices. Such materials can be selected for a zinc-bromine battery system from a wide variety of materials such as carbon, graphite, metallized carbon and ruthenized titanium. The respective inner walls 50 and 51 of the positive protective electrode sleeves 62 and 64 can be sized to be flush with the inner walls of manifolds 42 and 48, respectively. Metallized Carbon Corporation M-14 and Airco Speer Grade 580 can be used as materials for the positive electrodes. Sleeves 54 and 58 in manifolds 38 and 40, respectively, have similar requirements.
The negative protective annular electrodes 52, 52', 56 and 56' in the zinc-bromine system illustrated in FIG. 1, may have a more complicated structure than their counterpart positive protective electrodes. Electrolytes will flow (arrows 23 and 25) directly through annular electrode sleeves 52 and 56 in respective manifolds 38 and 44. The structure of a typical annular electrode 56 is shown in more detail with respect to FIG. 2.
The annular negative protective electrode 56 is comprised of an outer sleeve 70 and an inner porous liner 72. The inner wall 74 of the liner can be made to be flush with the inner wall 76 of the manifold 44 to minimize hydraulic pressure drop losses. The sleeve 70 can be comprised of carbon and/or graphite materials such as Metallized Carbon Corporation M-14 or Carbon Technologies Grade 101. Same grades of ruthenized titanium will also work.
Sleeve 70 is fed (arrow 71) a bromine-rich electrolyte, such as via a tube 78, which derives the bromine-rich electrolyte from a reservoir (not shown). The bromine-rich electrolyte is returned (arrow 73) to the reservoir via tube 82. The flow of the bromine-rich electrolyte through the sleeve 70 is for the purpose of supplying the electrolyte flowing through the annular electrode 56 into manifold 44 with bromine ions (Br - ). The inner porous sleeve 72 is for the purpose of assuring that substantially only bromine ions (Br - ) pass into the electrolyte, and this liner, therefore, prevents or retards the passage of the bromine-rich electrolyte proper into the electrolyte. The liner 12 is designed to pass ionic currents at low resistance.
The liner 72 can be composed of sintered, microporous polypropylene. The pores of the liner 72 can be filled with ion exchange material.
The liner 72 may be made from other microporous and ion-selective plastics and ceramics depending upon the particular chemistry of the reaction system. For example, in an electrolysis system generating oxygen and hydrogen at respective anode 14 and cathode 16 surfaces, protective electrode reactions at electrodes 52, 56, 52' and 56' could generate hydrogen, and protective electrode reactions at 54, 58, 54' and 58' could generate oxygen. Reactions at protective electrodes 56 and 56' would then introduce hydrogen in the electrolyte containing the cell system product oxygen. In a similar manner, the reactions at protective electrodes 54 and 54' would then introduce oxygen into the hydrogen product stream. In some situations, these mixtures would be undesirable, i.e., explosive mixtures could be formed. The use of a liner 72 to separate and remove these undesirable products from the system would be useful. The protective electrode reactions at electrodes 52 and 52' produce hydrogen and at electrodes 58 and 58' produce oxygen. These reactions are compatible with the system, since hydrogen and oxygen are respectively added to the electrolytes where system hydrogen and oxygen production is occurring. In this situation, there is no need for a liner 72. The composition of the liner 72 in this situation will be compatible with the electrolysis reaction.
In the negative protective annular electrode 56 of FIG. 2, the graphite sleeve 70 is fed current via a tantalum wire 84, which current reduces Br 2 to Br - . Other wire materials are possible as aforementioned.
In supplying the sleeve 70 with bromine-rich electrolyte, the flow may be continuous or intermittent, but must meet or exceed the stoichiometry of the electrode current.
Referring to FIGS. 3a through 3d, various possible radial cross-sections for the inner wall of the annular electrodes are shown. FIG. 3a depicts the normally circular cross-section for the annular electrode. FIGS. 3b, 3c and 3d, respectively, illustrate oval, hexagonal and square geometries (not all shapes are shown here). The purpose of shaping the radial cross-section in this manner may be for several reason: (a) to be compatible with the manifold geometrics; (b) to provide for different electrolyte flow characteristics; (c) to provide for various current density profiles along the manifold so that each cell will have its respective shunt current voltage drop matched with the voltage potential at that cell's respective position in the manifold.
Similarly, the normally straight inner wall 74 (FIG. 2) of the annular electrodes may be designed to have a different axial cross-section as illustrated in FIGS. 4a, 4b, and 4c. FIG. 4a shows a tapered inner wall; FIG. 4b depicts a curved inner wall; and FIG. 4c illustrates an irregular-shaped inner wall. The reasons for designing the axial cross-section of the annular electrode this way are similar to, and compatible with, the aforementioned objectives.
From the above design variations, it is meant to convey the thought that the meaning of "annular electrode" is not necessarily that type of electrode which has a straight cylindrical shape.
The aforementioned materials suggested for the electrode parts, generally pertain, and are applicable, to a zinc-bromine system. The invention is not to be construed as being limited to either a zinc-bromine system or to the particular materials selected. It will be understood by the skilled practitioner that other systems or reactions will generally require different or similar materials. The scope and spirit of the invention are meant to encompass these obvious modifications.
Having described the invention, what is desired to be protected by Letters Patent is presented by the following appended claims. | Shunt currents can be eliminated in electrochemical devices by introducing nulling currents via auxiliary electrodes. In electrochemical devices including those having a circulating electrolyte, such electrodes are designed to have a generally annular shape in order to provide a substantially uniform current density profile along a common electrolyte carrying manifold. The uniform current density profile allows for the elimination of these harmful shunt currents with a minimum of power consumption. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] Not applicable.
FIELD OF THE INVENTION
[0002] This disclosed technology relates to a grid-connected energy storage system that can make more efficient use of intermittent renewal energy sources, as well as a method of balancing the load of the power grid.
BACKGROUND
[0003] The amount of power available from the grid is usually determined by the power generation capacity connected to the grid, which should at least meet peak demand. On the other hand, during off-peak hours, the energy demand may be very much smaller. Therefore, excess energy is available for storage. About 20% of the annual kilowatt hours (KWH) consumed in the US comes from peaking power plants, which costs substantially higher. Just store 3% electricity, and it would reduce 30% of the cost to generate peak electricity demand.
[0004] Electrical demand varies considerably and often rapidly with the time of day, day of week, and season. Baseload generating plants, e.g. coal fired and nuclear, cannot meet rapidly shifting demands, because their time response is beyond hours while seconds to minutes are often desired. Recently, greater interest has been placed in utilizing renewable energy sources. However, the sun doesn't shine at night, the wind doesn't always blow, and tides, waves and currents fluctuate. To maximize usage of the intermittent renewable energy as well as to meet the varying demands, many studies have been carried out on how to store the power generated by these sources so that it can be used when it's needed.
[0005] Pumped hydro is the most common and well-known technology but has siting restrictions and major environmental concerns for new construction. The total capacity is only 2% of grid electricity—and it's unlikely to get much larger. Also, the round trip energy efficiency is about 70%, so a substantial fraction of the input power is lost. The other energy storage options—flywheels, batteries, chemical energy storage, thermal, superconducting magnetic energy storage and mechanical lifting against gravity—fall into the categories of micro energy storage that is too limited in capacity, too expensive, or less energy efficient. The round trip energy efficiency, cost, scale up capability and quick response are among the major considerations of energy storage methods to be developed.
[0006] Rechargeable battery technology has been actively investigated in Sodium-sulfur (NaS), flow batteries, lead acid/lead carbon, lithium ion, aluminum-ion, NIMH and NiCad but are limited to storage capacity. Due to the resulting electrolyte size limitations, multiple cells are assembled into large array of cells that require over 20,000 cells per MW capacity. There are two unconventional electricity storage technologies, which are incorporated herein by references: liquid metal battery by Sadoway et al in US patent Application 2008/0044725, entitled “High-Amperage Energy Storage Device and Method”, and energy storage in aluminum metal by Woodall et al in U.S. Pat. No. 8,080,233, entitled “Power generation from solid aluminum”. Both approaches solved the storage capacity issue by building large single cell using technology similar to the aluminum smelter process; however, Sadoway process suffers from typical battery round-trip efficiency minus expected thermal energy losses at 700° C. operating temperature, while Woodall process results in compounding degradation of energy efficiency in electrolysis, aluminum-water reaction for hydrogen and electricity production from hydrogen fuel cell or internal combustion engine.
[0007] Energy storage is of primary importance in increasing the efficiency and scheduling of alternative sourced electrical power. While commercial utility power plants provide substantially continuous baseload energy during extended periods of weeks and months, most alternative energy systems that use solar or wind power are inherently intermittent because of variations in the input energy (night, clouds and wind speeds outside the operational window). At night, when energy requirements are relatively low, the produced but unused energy is effectively “wasted”. Although renewable energy sources are inherently intermittent and therefore somewhat inefficient, there is a vast market available for otherwise wasted energy, provided practical storage and conversion to electricity is available for use at alternative times. The present invention provides a means of taking advantage of this potential market and opening up opportunities for both suppliers and users of electrical energy. For suppliers, it provides a means for off-loading or decreasing demand during periods of normally high demand with the potential result of reducing the frequency to add or replace generating equipment. It also allows suppliers to sell more energy during traditionally low demand periods (night time) at competitive rates and allows for better balancing for the grid. For users, it provides a means of time-shifting the times they purchase electricity from the grid and saves a significant amount of money by purchasing at competitive rates during such low demand times, and then using the stored energy during times when rates and demand are highest. By combining the storage techniques of the present invention with auxiliary power sources, users can significantly reduce their electrical power costs.
SUMMARY OF THE INVENTION
[0008] High-density energy storage by battery seeks light elements in the Periodic Table with high electrochemical potential and multiple electron transfers. Because aluminum is trivalent, it can achieve 3-4 times the specific energy density of a lithium-ion battery. The element is abundant on Earth, and its various forms of compounds are environmentally benign comparing to other solutions. Processing various aluminum chemicals are already in large scale and the existing infrastructure can be maximum utilized. Electrolysis of aluminum oxide is the basic chemical reaction of aluminum smelter cell, the single largest electricity consumer that consumes about 4-6% of the entire grid energy. It's an electrochemical process that runs at high temperatures, and at a current of hundreds of thousands of amps over a sustained period of years. However, it is only half of a battery because the reaction is not reversible for electricity generation.
[0009] The present invention stores energy from an electrical grid by making aluminum metal intermittently whenever excess electricity is available from the grid, and releases the electric load back into the grid during peak demand by holding aluminum smelter cells idling. The new baseload with energy storage is effectively higher than the existing baseload, as shown in FIG. 1 , making aluminum smelter cells a “passive battery”.
[0010] The fact that energy represents a large part (some 25%) of the costs associated with primary aluminum production means that producers have always had a vested interest in minimizing electricity consumption. It is estimated that, as much a 0.7 quadrillion BTUs/year are consumed in the process of maintaining grid balance while none of that energy is delivered to the end user. Because of the multiple benefits, improved economics for both the industrial and utility sectors warrants significant benefits from this approach.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] A fully enabling disclosure of the present invention, including the best mode thereof to one of ordinary skill in the art, is set forth more particularly in the remainder of the specification, including reference to the accompanying drawings.
[0012] FIG. 1 illustrates baseload with and without storage (using example of BPA Balancing Authority Load & Total Wind Generation, at 5-minute intervals in 7 days between Apr. 5-11, 2012).
[0013] FIG. 2 shows design of an aluminum smelter cell with vacuum thermal insulation shell.
[0014] FIG. 3 shows design of an aluminum smelter cell with external heating and insulation to maintain internal temperature.
DETAILED DESCRIPTION OF THE INVENTION
[0015] Reference will now be made in detail to the embodiments of the invention, one or more examples of which are set forth below. Each example is provided by way of explanation of the invention, not the limitation of the invention. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope or spirit of the invention. For instance, features illustrated or described as part of one embodiment can be used on another embodiment to yield a still further embodiment. Thus, it is intended that the present invention covers such modifications and variations as comes within the scope of the appended claims and their equivalents. Other objects, features, and aspects of the present invention are disclosed in the following detailed description. It is to be understood by one of ordinary skill in the art that the present discussion is a description of exemplary embodiments only and is not intended as limiting the broader aspects of the present invention, which broader aspects are embodied in the exemplary constructions.
[0016] In describing the various figures herein, the same reference numbers are used throughout to describe the same material, apparatus, or process pathway. To avoid redundancy, detailed descriptions of much of the apparatus once described in relation to a figure is not repeated in the descriptions of subsequent figures, although such apparatus or process is labeled with the same reference numbers.
[0017] In accordance with one or more embodiments, a solution for utility scale grid storage is disclosed herein that can provide power reliability to renewable energy sources that are inherently unreliable in nature, such as solar, thermal, photovoltaic (PV), wind, hydro, biomass and tidal. Existing aluminum smelter cells are incorporated in grid scale storage of low cost power and allow the load back to grid at high rates on demand by idling the cells. In this way, renewable utility operators can be provided with a grid storage solution that allows for 24-hour a day continuous power production without interruption when integrated in conjunction with conventional thermal power generation process (coal, nuclear, gas, oil), which also provides a storage component, whereby a portion of the energy can be stored and be available at any time on demand. Indeed, thermal power generation processes can respond to load changes within hours. The energy storage of only 4-6% grid energy by rapid altering aluminum production should be adequate to balance the entire grid in both renewable and nonrenewable power generation because load shifting beyond this storage capacity is at a slow pace that can be responded by thermal power plants.
[0018] By many measures, aluminum remains one of the most energy-intensive materials to produce. Aluminum production is the largest consumer of energy on a per-weight basis and is the largest electric energy consumer of all manufactured products. Process heating accounts for 27 percent of the total energy consumed in U.S. manufacturing of aluminum. Process heating is required for holding, melting, purifying, alloying, and heat treating.
[0019] Aluminum reduction cells are used to produce aluminum by electrolysis of aluminum oxide, a process known as the Hall-Héroult process.
[0000] 2Al 2 O 3 +3C→4Al+2CO 2
[0020] Aluminum is formed at about 900° C., but once formed has a melting point of only 660° C. The smelting process required to produce aluminum from alumina is continuous; the potline is usually kept in production for 24 hours a day year around. A smelter cannot be easily stopped and restarted. If production is interrupted by a power supply failure of more than 3 hours, the metal in the pots will solidify, often requiring an expensive rebuilding process. Continuous bulk power supply is critical to the current design of aluminum smelters.
[0021] This issue is solved by redesigning the smelter cell with much better thermal insulation. The best thermal insulation technology cuts off heat transfers, i.e., conduction, convection and radiation entirely. Refractory materials and vacuum jacketed insulation are combined in this application. As shown in FIG. 2 , a typical aluminum smelter cell is modified with vacuum jacketed insulation at the wall, bottom and top. Alternatively, external heating and insulation can be applied in such a way that the heater's internal temperature matches the outer surface of smelter, e.g., bottom of Steel Supporting Cradle. As shown in FIG. 3 , a typical aluminum smelter cell is added with an external heater and insulation at the wall, bottom and top. The heater is controlled to match the skin temperature of the smelter and therefore no heat transfer occurs. The heater can be electric, gas, oil, or any conventional heaters. The cell only loses heat in liquid aluminum product and gas scrubber during production, which is offset by joule heating and chemical reaction effects. If excess heat is generated, the smelter top can be partially opened to release heat. During idling, the gas scrubber and liquid aluminum flow are essentially stopped, therefore no significant heat losses are expected. A single aluminum smelter cell can be as large as 100 m 3 and can hold multiple tons of molten metal and electrolyte. The huge mass with a relatively small surface area allows molten temperature for days until cheap excess electricity is available to resume the production, however, intermittent production and idling at a frequency in seconds is also acceptable.
[0022] The Hall-Héroult process has been improved from 23.3 to about 13 kWh/kg since World War II, owing in part to the computerization of smelting cells. The computer takes into account the various current operating variables, so that the voltage in the pot is always the best for prevailing conditions. By reprogramming the control, the energy storage and load shedding can be instantaneous within milliseconds.
[0023] Diffusion of gas molecules into vacuum jacketed insulation increases significantly as the result of the high temperature operation (700-1000° C.) of aluminum smelter cells, therefore shortening the cycle length of the insulation effectiveness from typically 20 years in ambient and cryogenic application to weeks and months in aluminum smelters. The vacuum jacketed insulation has to be evacuated periodically and a getter material is re-applied/regenerated to extend the service cycle length. The getter material is a deposit of reactive material that is placed inside vacuum jacketed insulation, for the purpose of completing and maintaining the vacuum. When gas molecules strike the getter material, they combine with it chemically or by adsorption. Thus the getter removes trace amounts of gas from the evacuated space.
[0024] The method can be used to store energy during periods when excess supply is available on the electrical grid, and then release the load during times of higher demand. Thus, the method can be utilized by a utility to reduce excess capacity requirements, and therefore reduce costs. Furthermore, the method can be utilized to supply high quality power by grid rebalancing and power problem correction as well as other ancillary services. The round trip efficiency is close to 100% since there is no discharge loss in the cell and all “would be” electricity load is available for the grid.
Example 1
[0025] Example of an erratic electricity load at 5-minute intervals in 7 days is shown in FIG. 1 . Wind power varies even more. Data was taken from the BPA Balancing Authority Load & Total Wind Generation during Apr. 5-11, 2012 for illustration purposes. Aluminum production consumes about 5-6% grid power globally (4% in the US). By intermittent aluminum production, excess electricity can be stored as chemical energy in aluminum metal production. During high electricity demand from the grid, aluminum smelters can be set at idle, effectively increasing baseload by the amount that the aluminum smelter plant would consume. The aluminum smelter plant can work as a “passive battery” for energy storage and can return its load to the grid when it is needed. Both storage and load release can be instantaneous, and round trip efficiency can be just slightly lower than 100% only for heat loss during the idling of an aluminum smelter. Double capacity of an aluminum smelter plant will be needed for the same productivity in about 50% of production time.
Example 2
[0026] FIG. 2 shows the new design of an aluminum smelter cell with vacuum thermal insulation at the cradle and top cover. The current aluminum smelter cell does not operate intermittently as required in Example 1 because the molten metal and electrolyte in the smelter would solidify after prolonged idling. By changing the design to FIG. 2 , heat transfer by conduction, convection and radiation are reduced to minimum; therefore, the smelter cell can be left idling anytime as needed. This capability is important to enable its electricity load back to the grid.
Example 3
[0027] FIG. 3 shows another design of an aluminum smelter cell with external heating and insulation to maintain the internal temperature of the smelter cell. Heat only transfers from high temperature to low temperature. When external heaters are set to match the skin temperature of cradle and top cover, temperature gradient becomes zero and heat transfer essentially stops. The smelter cell itself is therefore adiabatic. | Grid energy storage is very challenging due to its large scale, required quick response, versatility, round trip efficiency, and new system infrastructure. However, the benefit is also huge because it would enable utilisation of intermittent renewable energy, leverage load, and allow energy management in hours/diurnal to seconds/minutes. A new invention is described to store up to 4-6% the entire grid energy by aluminum production, while returning its baseload back to the grid by idling aluminum smelter cells. The round trip efficiency will be close to 100%; switching between storage and load release can be instantaneous. | 2 |
CROSS-REFERENCE TO RELATED APPLICATION
The disclosure of Japanese Patent Application No. 2003-324601 filed Sep. 17, 2003 including specifications, drawings and claims is incorporated herein by references in their entireties.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a method and a device for separating submicron particles mixed into liquid. The present invention particularly relates to a method and a device for separating particles, the method and the device being appropriately applied to a micro total analysis system (Micro-TAS), a micro electro mechanical system (MEMS), and the like, in which analytical chemistry and micro chemistry technologies are integrated into a palm-size chip in thermal fluid mechanics, electrochemistry, and analytical chemistry on a micro/nano scale by use of a micromachine technology.
2. Description of the Related Art
The research and development of Lab-on-a-chip and Micro-TAS which are conceived to become large industry in a few years, that is, a palm-size device into which an experiment, analysis and the like at a conventional laboratory level are integrated is rapidly conducted. Many micro channels, the width of which is from several tens μm to several hundreds μm, are disposed in this device, and it is desired that the analysis of a little liquid sample, the reactive synthesis of a chemical agent and the like be effectively and rapidly carried out. A device to make a blood test, a DNA judgment operation, or the like possible has already been on the market in actuality. It is expected, on the other hand, to make the device further multifunctional, and especially it is deeply desired to establish technology for selectively separating particular particles and a particular material existing in a liquid sample.
Until now, the separation operation of the submicron particles existing in the analyzed liquid sample (in a buffer solution, in general) is generally carried out with the use of a large-scale centrifugal separator. In this method, it is possible to precisely separate and extract the particular particles by use of a filter which is smaller than the diameter of the objective particle. Thus, this method has been positively used in the field of analytical chemistry and the like. It is difficult, however, to add a centrifugal separation function to the device for the purpose of rapidly carrying out a series of chemical reaction operations in the device, so that there is a problem that the device is complicated.
Therefore, focusing attention on the viewpoint of thermal fluid mechanics, separation technologies using rheological properties in the device are developed in recent years. An H-filter (Paul Yager et al., MicroTAS 1998 proceedings, 202-212), being one of the separation technologies, which separates the particles or the material existing in the buffer solution by use of difference in a diffusion coefficient of the particles or the material, has an advantage that external mechanical driving force is not necessary.
The development of a cell sorter are also carried out (Anne Y. F. et al., Nature 1999, Vol. 17, 1109-1111). In this technology, the particles to be separated are impregnated with a fluorescent material, and are monitored with a sensor and separated by rheological switching control, and the like.
Furthermore, Japanese Patent Laid-Open Publication No. 2002-233792 proposes a method in which a solution including the particles flows through a channel and a voltage is applied at the midpoint of the channel so as to generate an electric field in the direction of crossing the channel. The particles are attracted by the generated electric field and captured on this side in the channel.
The H-filter, however, cannot completely separate the particles and the material by a single operation due to its principle. The addition of a particle separation function such as, for example, the centrifugal separation function makes the structure of the device complicated. The cell sorter, on the other hand, is hard to use for the particle separation operation in a field with high concentration such as an actual rheological field. Furthermore, the method disclosed in Japanese Patent Laid-Open Publication No. 2002-233792 has a problem that the method cannot separate the particles with enough efficiency.
SUMMARY OF THE INVENTION
In view of the foregoing problems, various exemplary embodiments of the present invention provide a device with simple structure for completely separating particular particles by a single operation, and a method thereof.
Various exemplary embodiments of the present invention provide a method for separating submicron particles mixed in liquid. The method comprises the steps of: providing a micro channel which has channels disposed in the shape of any one of the letter T, the letter Y, and a cross, and is structured so that the liquid flows into a single channel from a plurality of intake channels, and flowing a plurality of types of liquid having different electrical conductivity into the respective intake channels of the micro channel; and applying an electric field to the micro channel to attract objective submicron particles to one side of an outlet channel by an electrokinetic driving flow in the micro channel. Thereby, the abovementioned object can be achieved.
The micro channel may be a two-liquid mixing type of T-shaped micro channel.
Various exemplary embodiments of the present invention provide a particle separation device for separating submicron particles mixed in liquid. The particle separation device comprises: a micro channel having channels disposed in the shape of any one of the letter T, the letter Y, or a cross, and is structured so that the liquid flows into a single channel from a plurality of intake channels; means for flowing a plurality of types of liquid having different electrical conductivity into the micro channel; and means for applying an electric field to the micro channel to attract objective submicron particles to one side of an outlet channel by an electrokinetic driving flow in the micro channel.
According to various exemplary embodiments of the present invention, in, for example, the two-liquid mixing type of T-shaped micro channel having extremely simple structure, it is possible to completely separate the submicron particles in a single operation from, for example, the liquid with low electrical conductivity to the liquid with high electrical conductivity by use of the plurality of types of liquid having largely different conductivity. Also, various exemplary embodiments of the present invention are applicable to the particle concentration of every type of liquid, and never needs special machining of the channels and the like, so that it is possible to immediately apply various exemplary embodiments of the present invention to an actual device. Furthermore, it is possible to selectively separate and extract the submicron particles by difference in electric charge of the particles, and locally vary the particle concentration by varying the strength of the electric field. Therefore, various exemplary embodiments of the present invention contributes to making the device more multifunctional and further enhancing the performance of the device as elemental technology.
BRIEF DESCRIPTION OF THE DRAWINGS
The above object, features and advantages of the present invention, as well as other objects and advantages thereof, will become more apparent from the description of the invention which follows, taken in conjunction with the accompanying drawings, wherein like reference characters designate the same or similar parts and wherein:
FIG. 1A is a perspective view showing the structure of a first exemplary embodiment of the present invention, FIG. 1B is an explanatory view of a channel and FIG. 1C is a sectional view of a micro channel;
FIG. 2 is a perspective view showing the structure of a measurement device according to the first exemplary embodiment of the present invention;
FIG. 3 is a diagram showing instantaneous images of a rheological field in a junction section of a T-shaped micro channel to explain the operation of one exemplary embodiment of the present invention;
FIG. 4 is a diagram showing velocity distribution vectors and streamlines of submicron particles according to the same;
FIG. 5 is a diagram showing velocity components of the submicron particles in the x-direction in a downstream area of the junction section according to the same;
FIGS. 6A to 6C are diagrams showing streamlines of the synthesis of a static driving flow and an electroosmotic flow according to the same;
FIG. 7 is a diagram showing instantaneous images of the rheological field in the downstream area of the micro channel according to the same;
FIG. 8 is an explanatory view of a channel according to the first exemplary embodiment of the present invention;
FIG. 9 is an explanatory view of a channel according to a second exemplary embodiment of the present invention;
FIG. 10 is an explanatory view of a channel according to a third exemplary embodiment of the present invention; and
FIG. 11 is an explanatory view of a channel according to a fourth exemplary embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Exemplary embodiments of the present invention will be hereinafter described in detail with reference to the accompanying drawings.
In a first exemplary embodiment of the present invention, a microchip 10 having a simple two-liquid mixing type of T-shaped micro channel 12 as shown in a perspective view of FIG. 1A , an explanatory view of FIG. 1B and a sectional view of FIG. 1C is used. As shown in FIG. 1C , this micro channel 12 made of PDMS (polydimethylsiloxanc) 14 by use of a soft lithography method was cemented to a cover glass 16 (diameter of 50 mm and thickness of 170 μm) for a microscope. The width of channels is 200 μm and 400 μm, and the depth thereof is 50 μm.
An HEPES buffer solution of 5 mM was used as a working fluid. Two types of a solution A and a solution B, the electrical conductivity of which was at a ratio of one to ten as shown in table 1, were prepared by adding potassium chloride (KCl)
TABLE 1
5 mM HEPES
Solution A
Solution B
pH
7.2
7.2
Electrical
270
2650
conductivity (μS/cm)
Polyethylene submicron particles (excitation wavelength of 540 nm/light emission wavelength of 560 nm), which were kneaded with a fluorescent material and had a diameter of 1.0 μm, were mixed into each solution at a volume ratio of 0.2%. Since carboxyl was added to the surface of the submicron particle used in this method, the surface of the particle was negatively charged in the buffer solution. Thus, the particles were dispersed in the solution by Coulomb force.
The solution A was injected into a channel end 1 shown in FIG. 1B , and the solution B was injected into a channel end 2 . The solutions A and B were conveyed by a static driving flow due to difference in a fluid level with a channel end 3 .
Then, platinum electrodes 21 , 22 and 23 were inserted into each of the channel ends 1 to 3 , respectively. A high voltage power source 30 applied a direct-current high voltage of 300 to 700V to the channel ends 1 and 2 , and the channel end 3 was grounded. In other words, the working fluid is driven by the synthesis of the static driving flow and an electroosmotic flow, which is generated by the application of an electric field.
A measurement device 40 which used a fluorescent microscope shown in a lower portion of FIG. 2 was used as a device for taking an image and measuring a flow inside the micro channel. An Nd:YAG laser (λ=532 nm) 42 being continuous light was used as a light source of the measurement device 40 . Light from the Nd:YAG laser 42 was applied to the inside of the channel by use of a light transmitting fiber 44 , a dichroic mirror 46 and an objective lens 48 , and only a fluorescent light emission wavelength (λ=560 nm) from the submicron particles which were kneaded with the fluorescent material was extracted by use of various optical filters 50 . A cooled CCD camera 52 with 494 pixels×656 pixels×12 bits took images.
The foregoing objective lens 48 at a magnifying power of 40 times has the effect of restraining the distortion of the image caused by the refraction of light. An oil-immersed objective lens (40×, NA=1.30) with a shallow measurement depth was used as the objective lens 48 . According to an expression for a measurement depth which is defined by Meinhart et al. (Meinhart et al., Meas. Sci. Technol., Vol. 11, 809-814, 2000), the measurement depth of this measurement device is 3.7 μm when the diameter of the particle is 1.0 μm.
The velocity of the submicron particles was measured from the images taken by the measurement device 40 with the use of a high spatial resolution micro particular image current meter (micro PIV), to verify the physical mechanism of particular separation. FIG. 3 shows time series instantaneous images in a junction section 12 A (refer to FIG. 1B ) of the T-shaped micro channel 12 , when electric field application start time is defined as t=0. At t=0, the solutions A and B sent from the channel ends 1 and 2 at a regular flow rate flowed in a downstream direction (the y-direction) by the static driving flow, and the submicron particles evenly dispersed in each solution followed the static driving flow. After the start of the application of the electric field, the submicron particles existing in the solution A with low electrical conductivity moved to the solution B with high electrical conductivity. At t=3.6 sec, an uneven particle concentration field was observed.
To grasp a movement phenomenon of the submicron particles in detail, FIG. 4 shows velocity vectors of the submicron particles in the junction section 12 A (depth direction z=25 μm) measured by use of the micro PIV at a steady state after the application of the electric field. When velocity is calculated, velocity vectors at one hundred times are averaged by time in order to remove the effect of the Brownian movement of the submicron particles on velocity detection. It was quantitatively confirmed from FIG. 4 that the x-direction velocity of the submicron particles existing in the solution A was increased.
In the same manner, the x-direction velocity components u of the submicron particles in downstream areas 12 B and 12 C (depth direction z=5 μm and 25 μm) of the junction section shown in FIG. 1B are calculated and shown in FIG. 5 . In all of the four areas in which measurement was carried out, it was found out that the submicron particles were moved in the x-direction, and were in movement velocity distribution, the peak value of which was in the vicinity of the center of the channel (mixture area of the solutions A and B by molecular diffusion) in which the gradient of electrical conductivity was especially large.
The movement of the submicron particles in the x-direction like this is not observed when two types of solutions with equal electrical conductivity flow. The ratio of electrical conductivity between the two types of solutions is an important parameter. When the ratio of electrical conductivity between the two types of solutions was 1:5 or 1:25, a similar phenomenon was confirmed in the present method. Namely, it is conceivable that an electric field in the x-direction occurs during the application of the electric field due to the effect of the gradient of electrical conductivity, which is formed in a case that two types of liquid with largely different electrical conductivity flow. The submicron particles negatively charged in the liquid are not only driven by convection (the sum of the static driving flow and the electroosmotic flow), but also driven in the x-direction by electrophoresis.
To elucidate the movement mechanism of the submicron particles by the application of the electric field when the gradient of electrical conductivity exists, a numerical simulation analysis was carried out. FIG. 6A shows streamlines of the synthesis of the static driving flow being a flow of the fluid itself and the electroosmotic flow. Both of the solutions A and B flow approximately symmetrically with respect to the center of the channel. Electric lines of force, however, are formed so as to cross from the solution B with high electrical conductivity to the solution A with low electrical conductivity as shown in FIG. 6B , so that the negatively charged particles are driven by the electrophoresis. Ultimately, as shown in FIG. 6C , the particles are separated from the solution A with low electrical conductivity to the solution B with high electrical conductivity.
Ultimately, as shown in instantaneous images of a rheological field of FIGS. 7A to 7C , all of the evenly dispersed particles are moved into the solution B with high electrical conductivity in the downstream area 12 C of the junction section (depth direction z=25 μm) after the application of the electric field. Therefore, it is possible to separate the particles. FIG. 7A is the instantaneous image before the start of the application of an electric field, and FIG. 7B is the instantaneous image after the application of an electric field of 500V. FIG. 7C is the instantaneous image after the application of an electric field of 750V.
In an actual application, as shown in FIG. 8 , the selective separation and extraction of submicron particles 8 due to difference in electric charge of the particles 8 are possible by use of the asymmetrical distribution of electric potential formed by the gradient of electrical conductivity. It is possible to locally vary particle concentration by varying electric field intensity. Since such an operation is carried out with the use of the simple T-shaped micro channel and the electrodes, it is possible to easily apply this method to an actual Micro-TAS device.
According to this exemplary embodiment, the liquids with different electrical conductivity are made by adding potassium chloride KCl to the buffer solution. This is preferable because the diffusion coefficient of potassium K is almost equal to that of chlorine Cl. A material for varying the electrical conductivity may be sodium chloride NaCl other than potassium chloride KCl, for example.
In the foregoing exemplary embodiment, the HEPES buffer solution is used as the working fluid, but the type of the working fluid may be any other liquid as long as the liquid can be kept at a constant pH.
In the foregoing exemplary embodiment, the same particles are mixed into both of the solution A and the solution B. In a second exemplary embodiment shown in FIG. 9 , the present invention is applicable to a case where, for example, particles 8 mixed into a solution A are moved into a solution B. In a third exemplary embodiment as shown in FIG. 10 , the present invention is applicable to a case where three types or more particles (“+,” “−,” and “3−” in the drawing) mixed in a solution are separated into three groups in accordance with respective electric charges. In a fourth exemplary embodiment shown in FIG. 11 , the present invention is applicable to a case where a plurality of different particles 8 A, 8 B, 8 C, and 8 D injected from both ends are separated.
The shape of the micro channel may be the letter Y or a cross in addition to the letter T.
Although only a limited number of the embodiments of the present invention have been described, it should be understood that the present invention is not limited thereto, and various modifications and variations can be made without departing from the spirit and scope of the invention defined in the accompanying claims. | A plurality of types of liquid with different electrical conductivity flow through a micro channel having a plurality of channels. When an electric field is applied thereto, an electrokinetic driving flow generated in the micro channel attracts objective submicron particles to one side. Therefore, the particles are completely separated in a single operation by use of the micro channel having extremely simple structure, without the necessity of special machining of the channels and the like. | 1 |
FIELD OF THE INVENTION
[0001] The present invention relates to an unbleached paper product and the preparation method thereof. More specifically, the invention relates to the application of unbleached cereal straw pulp to preparation of an unbleached paper product as a main raw material and the unbleached paper product prepared by the same.
BACKGROUND OF THE INVENTION
[0002] Household paper is a common consumable product, but due to psychological demand for whiteness and requirement for some physical indexes, paper is usually mainly prepared from bleached wood pulp, and the prior art gives some technical schemes for preparing the household paper, for example:
[0003] CN94105089 relates to complete wheat straw high-efficiency pharmaceutical and healthcare toilet paper, and a process for the complete wheat straw high-efficiency pharmaceutical and healthcare toilet paper of the invention comprises paper manufacturing.
[0004] CN200410026132 discloses a method for preparing household paper by compounding collagen fiber and plant fiber, and specifically the method comprises mixing bleached softwood (hardwood) pulp with wheat straw pulp to attain 1-4% mass concentration of the pulp, mixing the bleached softwood (hardwood) pulp and the wheat straw pulp with collagen fiber pulp, and adding a softening agent to a machine chest; then feeding resulting pulp to a paper machine wire after mixing; and pressing, drying, reeling and processing wet paper to obtain a finished product.
[0005] Pollution from paper and pulp making industry mainly lies in two steps of treating and discharging black liquor after cooking and bleaching pulp, in which pollution from the pulp bleaching step is particularly obvious. With respect to discharge of conventional chloric bleaching wastewater, wastewater contains common aquatic environment pollution factors such as COD and BOD and other special pollutants. For example, in the case of chlorine bleaching and hypochlorite bleaching, wastewater discharged from bleaching every 1 t of bagasse pulp contains 150-250 g of chloroform produced in hypochlorite bleaching, and wastewater discharged from bleaching every 1 t of wood pulp contains 700 g of chloroform. In addition to chloroform produced in the chlorine bleaching, the wastewater also contains more than 40 organic chlorides in which chlorophenols are the most, such as dichlorophenol and trichlorophenol, and contains dioxins and chlorinated furans, a majority of which are highly toxic. AOX has teratogenetic, cancerogenic and mutagenic hazards.
[0006] Developed countries and regions such as Western Europe, Hong Kong, Taiwan, Japan and Korea provide addition of harmful substances to office paper production processes, providing that neither chloric bleacher nor fluorescer can be used, and give mandatory requirement for content of harmful substances in the production process, and Japan controls whiteness (<70%) to avoid excessive use of fluorescers. The standards are that contents of COD and AOX in the wastewater are not more than 20 Kg/t paper and not more than 0.3 Kg/t paper respectively. In order to solve water pollution problem, all enterprises and the society pay a high price.
[0007] Toilet paper or household paper is prepared from wheat straw or plant fiber as the raw material in the above reference documents, as pulping method in the prior art is relatively lagged, grass material is always cooked to low hardness during preparing pulp from grass plant as the raw material, for example, the grass materials are cooked to hardness with 11-14 potassium permanganate number. In order to achieve such low hardness, amount of cooking liquor and time of heating and insulation are necessarily much, while high-temperature cooking and insulation in high-concentration chemical liquor certainly causes degradation and damage of cellulose and hemicellulose in the grass material, and inherent length of fiber can not be kept well, thus prepared straw pulp has low strength, and then resulting toilet paper and household paper have low quality. In addition, the bleaching step is necessary in the preparation method of the toilet paper and the household paper in the prior art, produces great pollution to environment and products, and produces dioxins, adsorbable organic halide and other carcinogenic substances, which produces great damages to users; moreover, even though wood pulp is used for preparing a variety of paper in the preparation method of the prior art, the fluorescers and other substances harmful for human health are also added and remained in products more or less, which can cause damages to health of users.
[0008] Therefore, the prior art does not describe how to prepare higher-performance pulp suitable for preparing various high-quality paper products with respect to the grass material, for disadvantages of the prior art, in more detail, and for the reason, the invention is proposed.
SUMMARY OF THE INVENTION
[0009] A primary objective of the invention is to provide a grass type unbleached paper product which comprises unbleached toilet paper, unbleached towel paper, unbleached wiping paper, unbleached duplicating paper, unbleached lunch box, unbleached food wrap paper and unbleached printing paper. The paper product has high strength, and neither dioxins nor adsorbable organic halide is detected in the harmful substance detection test.
[0010] In order to achieve the objective mentioned above, the invention uses the following technical scheme:
[0011] An unbleached paper product prepared from cereal straw pulp as a raw material has a whiteness of 25-60% ISO, preferably 35-45% ISO, and the cereal straw pulp is unbleached.
[0012] The unbleached straw pulp of the invention has a breaking length of 5.0-7.5 km, tear strength of 230-280 mN, folding number of 40-90, whiteness of 25-45% ISO and beating degree of 32-38° SR and preferably has a breaking length of 6.5-7.5 km, tear strength of 250-280 mN, folding number of 65-90, beating degree of 32-36° SR and whiteness of 35-45% ISO.
[0013] The unbleached paper product of the invention comprises unbleached toilet paper, unbleached towel paper, unbleached wiping paper, unbleached duplicating paper, unbleached lunch box, unbleached food wrap paper and unbleached printing paper.
[0014] The unbleached paper product of the invention is unbleached toilet paper, pulp used for the unbleached toilet paper comprises 70-100% of unbleached straw pulp and 0-30% of unbleached wood pulp, and transverse suction range of a finished layer thereof is 30-100 mm/100 s, preferably 40-100 mm/100 s and more preferably 50-80 mm/100 s.
[0015] The unbleached toilet paper of the invention has a tensile index of 4-12 N.m/g, preferably 8-12 N.m/g; the unbleached toilet paper has a softness of 120-180 mN, preferably 120-150 mN; the unbleached toilet paper has an basis weight of 10.0-18.0 g/m 2 , preferably 11.0-13.0 g/m 2 .
[0016] The unbleached paper product of the invention is unbleached towel paper, pulp used for the unbleached towel paper comprises 70-100% of unbleached straw pulp and 0-30% of unbleached wood pulp, and longitudinal wet tensile strength of the unbleached towel paper is 22-55 N/m, preferably 30-45 N/m.
[0017] The transverse suction range of a finished layer of the unbleached towel paper of the invention is 30-100 min/100 s, preferably 40-100 mm/100 s, more preferably 50-80 mm/100 s.
[0018] The unbleached towel paper of the invention has a softness of 120-180 mN, preferably 120-150 mN, and the unbleached towel paper has an basis weight of 23.0-45.0 g/m 2 , preferably 30.0-40.0 g/m 2 .
[0019] The unbleached paper product of the invention is unbleached lunch box which is prepared from 70-100% unbleached straw pulp and 0-30% unbleached wood pulp and has performance parameter meeting requirements for Grade A product in GB 18006.1-1999.
[0020] The unbleached paper product of the invention is unbleached duplicating paper, pulp used for the unbleached duplicating paper comprises 50-80% of unbleached straw pulp and 20-50% of unbleached wood pulp, mean longitudinal and transverse breaking length of the unbleached duplicating paper is 3.2-7.5 km, preferably 4.5-7.5 km and more preferably 6.0-7.5 km.
[0021] Transverse folding number of the unbleached duplicating paper of the invention is 60-200 and preferably 80-185.
[0022] Basis weight of the unbleached duplicating paper of the invention is 60.0-75.0 g/m 2 , preferably 65.0-72.0 g/m 2 and more preferably 69.0-72.0 g/m 2 , and opacity thereof is 82.0-98.0% and preferably 90-98%.
[0023] The unbleached paper product of the invention is unbleached food wrap paper, pulp used for the unbleached food wrap paper comprises 50-70% of unbleached straw pulp and 30-50% of unbleached wood pulp, and breaking length of the unbleached food wrap paper is 3.2-7.61 cm and preferably 4.5-7.61 cm.
[0024] Basis weight of the unbleached food wrap paper of the invention is 45-65 g/m 2 and preferably 50-60 g/m 2 , and transverse folding number of the same is 90-200 and preferably 120-200.
[0025] Transverse tear strength of the unbleached food wrap paper of the invention is 300-600 mN and preferably 400-600 mN.
[0026] The unbleached offset printing paper of the invention has a whiteness of 30-60% ISO and is prepared from 65-85% of unbleached straw pulp and 15-35% of unbleached wood pulp.
[0027] Breaking length of the unbleached offset printing paper of the invention is 2.5-5.5 km and preferably 3.5-5.5 km.
[0028] Opacity of the unbleached offset printing paper of the invention is 82-98%, preferably 85-98% and more preferably 92-98%.
[0029] Folding number of the unbleached offset printing paper of the invention is 10-35 and preferably 15-35.
[0030] The unbleached paper product of the invention is unbleached wiping paper, pulp used for the unbleached wiping paper comprises 70-100% of unbleached straw pulp and 0-30% of unbleached wood pulp, and longitudinal wet tensile strength of the unbleached wiping paper is 22-55 N/m and preferably 30-45 N/m.
[0031] Transverse suction range of the unbleached wiping paper is 30-100 mm/100 s, preferably 40-100 mm/100 s, and more preferably 50-80 min/100 s.
[0032] The unbleached wiping paper has a softness of 120-200 mN, preferably 120-180 mN; and the unbleached wiping paper has an basis weight of 14.0-36.0 g/m 2 , preferably 18-28 g/m 2 .
[0033] Preparation of the unbleached straw pulp of the invention comprises cooking and washing steps, and the cooking step comprises obtaining high-hardness pulp with a potassium permanganate number of 16-28 and beating degree of 10-24° SR after cooking grass plants as the raw material; preferably the unbleached straw pulp is high-hardness pulp with a potassium permanganate number of 16-23 and beating degree of 10-24° SR after cooking grass plants as the raw material.
[0034] Preparation of the unbleached straw pulp of the invention comprises cooking and oxygen delignification steps, and the oxygen delignification comprises: pumping high-hardness pulp with the potassium permanganate number of 16-28 which is obtained after cooking to an oxygen delignification reaction tower and adding sodium hydroxide and oxygen; and allowing delignification reaction of the high-hardness pulp in the oxygen delignification reaction tower to obtain pulp with hardness being potassium permanganate number of 10-14.
[0035] Preferably, the oxygen delignification is single stage and executed in the oxygen delignification reaction tower; the high-hardness pulp is at 95-100° C. and 0.9-1.2 MPa at an inlet of the reaction tower and at 100-105° C. and 0.2-0.6 MPa at an outlet; alkali used in the oxygen delignification treatment is 2-4% of bone dry pulp based on sodium hydroxide, and oxygen added is 20-40 kg for every ton of bone dry pulp; and the high-hardness pulp reacts in the reaction tower for 60-90 min.
[0036] The straw pulp of the invention is prepared from grass plants as the raw material by cooking, washing, oxygen delignification steps, etc., and the grass material comprises one or a combination of a plurality of rice straw, wheat straw, cotton stalk, bagasse, reed or giant reed.
[0037] The unbleached paper product of the invention is prepared by beating the straw pulp as the main raw material in combination with a certain amount of unbleached wood pulp or other papermaking pulp if necessary, and then manufacturing paper with the pulp. As the straw pulp is high-quality unbleached straw pulp and has excellent performances such as high strength and high folding number, and the paper product is unbleached, strength of fiber is increased by 30%-50%, yield of fiber is increased by 10%, and strength of the paper product such as breaking length is greatly improved. The unbleached paper product can also greatly reduce pollution to environment, avoid generation of harmful substances and avoid damages to human health.
[0038] The paper product has no dioxins and adsorbable organic halide detected in a harmful substance detection test.
[0039] Another objective of the invention is to provide a preparation method of an unbleached paper product.
[0040] In order to achieve the objective mentioned above, the invention uses the following technical scheme:
[0041] A method for preparing the unbleached paper product, the method comprising:
(1 ) cooking the grass material, pressing, washing, disintegration and then performing oxygen delignification treatment to obtain the unbleached straw pulp; (2 ) beating the unbleached straw pulp and the unbleached wood pulp respectively to obtain beaten pulp; (3 ) mixing the unbleached straw pulp and the unbleached wood pulp or other papermaking pulp in step (2 ) based on parts by weight as required by the paper product, and blending the pulp even; and (4 ) manufacturing with the beaten pulp to obtain the unbleached paper product.
[0046] In the preparation method of the unbleached paper product of the invention, the step (3 ) also comprises adding other adjuvants required by paper product preparation except fluorescers during or before the mixing process. The preparation method is a conventional preparation method of various paper products in the prior art.
[0047] In the step (1 ) of the invention, the grass material is cooked to obtain high-hardness pulp with hardness of 16-28 and degree of beating of 10-24° SR.
[0048] The cooking of the invention comprises one of ammonium sulfite, anthraquinone-sodium hydroxide, sulfate or basic sodium sulfite cooking methods:
in the ammonium sulfite cooking method, ammonium sulfite used is 9-13% of the bone dry raw material; in the anthraquinone-sodium hydroxide cooking method, alkali used is 9-15% of the bone dry raw material based on sodium hydroxide; in the sulfate cooking method, alkali used is 8-11% of the bone dry raw material based on sodium hydroxide; and in the basic sodium sulfite cooking method, sodium hydroxide used is 11-15% of the bone dry raw material and sodium sulfite used is 2-6% of the bone dry raw material.
[0053] The cooking of the invention comprises one of ammonium sulfite, anthraquinone-sodium hydroxide, sulfate or basic sodium sulfite cooking methods:
[0000] 1 ) If the Grass Material is Cooked in a Spherical Batch Cooker or a Continuous Cooker: the ammonium sulfite cooking method comprises:
(1 ) adding cooking liquor to the grass material, in which ammonium sulfite used is 9-13% of the bone dry raw material, and liquor ratio is 1:2-4; and (2 ) feeding steam and heating to 165-173° C., in which time for the whole process of heating, relieving and insulating is 160-210 min;
the anthraquinone-sodium hydroxide cooking method comprises:
(1 ) adding cooking liquor to the grass material, in which alkali used is 9-15% of the bone dry raw material based on sodium hydroxide, liquor ratio is 1:2-4, and anthraquinone added is 0.5-0.8% of the bone dry raw material; and (2 ) feeding steam and heating to 160-165° C., in which time for the whole process of heating, relieving and insulating is 140-190 min;
[0059] The sulfate cooking method comprises:
(1 ) adding cooking liquor to the grass material, in which alkali used is 8-11% of the bone dry raw material based on sodium hydroxide, liquor ratio is 1:2-4, and sulfidity is 5-8%; and (2 ) feeding steam and heating to 165-173° C., in which time for the whole process of heating, relieving and insulating is 150-200 min;
[0062] The basic sodium sulfite cooking method comprises:
(1 ) adding cooking liquor to the grass material, in which sodium hydroxide used is 11-15% of the bone dry raw material by weight, sodium sulfite used is 2-6% of the bone dry raw material by weight, anthraquinone used is 0.02-0.08% of the bone dry raw material by weight and cooking liquor ratio is 1:3-4; and (2 ) feeding steam and heating to 160-165° C., in which time for the whole process of heating, relieving and insulating is 140-190 min
2 ) If the Grass Material is Cooked in a Vertical Cooker:
[0065] The ammonium sulfite cooking method comprises:
(1 ) adding cooking liquor to the grass material, in which ammonium sulfite used is 9-15% of the bone dry raw material, and liquor ratio is 1:6-10; and (2 ) filling the grass material in hot black liquor in the cooker by a filler, closing a cooker cover after the cooker is full, supplementing the cooking liquor at 130-145° C. while discharging air from the cooker and boosting to 0.6-0.75 MPa, and heating the cooking liquor to 156-173° C., in which time for heating, insulating and exchanging is 220 min; and finally pumping pulp to a blow tank;
[0068] the anthraquinone-sodium hydroxide cooking method comprises:
(1 ) adding cooking liquor to the grass material, in which alkali used is 9-17% of the bone dry raw material based on sodium hydroxide, liquor ratio is 1:6-9, and anthraquinone added is 0.5-0.8% of the bone dry raw material; and; (2 ) filling the grass material in hot black liquor in the cooker by a charger, closing a cooker cover after the cooker is full, supplementing the cooking liquor at 130-145° C. while discharging air from the cooker and boosting to 0.4-0.6 MPa, and heating the cooking liquor to 147-165° C., in which time for heating, insulating and exchanging is 170-200 min; and finally pumping pulp to a blow tank;
[0071] the sulfate cooking method comprises:
(1 ) adding cooking liquor to the grass material, in which alkali used is 8-13% of the bone dry raw material based on sodium hydroxide, liquor ratio is 1:6-10, and sulfidity is 5-9%; and (2 ) filling the grass material plant in hot black liquor in the cooker by a charger, closing a cooker cover after the cooker is full, supplementing the cooking liquor at 130-145° C. while discharging air from the cooker and boosting to 0.5-0.65 MPa, and heating the cooking liquor to 155-168° C., in which time for heating, insulating and exchanging is 180-220 min; and finally pumping pulp to a blow tank;
[0074] the basic sodium sulfite cooking method comprises:
(1 ) adding cooking liquor to the grass material, in which sodium hydroxide is 9-17% of the bone dry raw material by weight, sodium sulfite used is 4-8%, anthraquinone is 0.04-0.08% and cooking liquor ratio is 1:6-10; and (2 ) filling the grass material in hot black liquor in the cooker by a charger, closing a cooker cover after the cooker is full, supplementing the cooking liquor at 145° C. while discharging air from the cooker and boosting to 0.45-0.6 MPa, and heating the cooking liquor to 152-165° C., in which time for heating, insulating and exchanging is 180-220 min; and finally pumping pulp to a blow tank.
[0077] The oxygen delignification of the invention comprises:
(1 ) pumping the high-hardness pulp with hardness of 16-28 potassium permanganate number which is obtained after cooking to an oxygen delignification reaction tower, and adding sodium hydroxide and oxygen; and (2 ) allowing oxygen delignification reaction of the high-hardness pulp in the oxygen delignification reaction tower to obtain pulp with hardness of 10-14 potassium permanganate number;
[0080] Preferably, the oxygen delignification is single stage and executed in one oxygen delignification reaction tower; the high-hardness pulp is at 90-100° C. and 0.9-1.2 MPa at an inlet of the reaction tower and at 95-105° C. and 0.2-0.4 MPa at an outlet; alkali used in the oxygen delignification treatment is 2-4% of bone dry pulp based on sodium hydroxide, and oxygen added is 20-40 kg for every ton of bone dry pulp; and the high-hardness pulp reacts in the reaction tower for 60-90 min.
[0081] A use of unbleached straw pulp in preparation of the unbleached paper product according to any one of claims 1 - 3 .
[0082] The unbleached straw pulp has a breaking length of 5.0-7.5 km, tear strength of 230-280 mN, whiteness of 25-45% ISO, folding number of 40-90 and beating degree of 32-38° SR, and preferably has a breaking length of 6.5-7.5 km, tear strength of 250-280 mN, folding number of 65-90, beating degree of 32-36° SR and whiteness of 35-45% ISO.
[0083] A preparation method of the unbleached straw pulp comprises cooking, washing and oxygen delignification steps, and the cooking comprises obtaining high-hardness pulp with potassium permanganate number of 16-28 and beating degree of 10-24° SR after cooking grass plants as the raw material; preferably, the unbleached straw pulp is the high-hardness pulp with potassium permanganate number of 16-23 and beating degree of 10-24° SR after cooking grass plants as the raw material.
[0084] Preparation of the unbleached straw pulp comprises cooking, washing and oxygen delignification steps, and the oxygen delignification step comprises: pumping high-hardness pulp with the potassium permanganate number of 16-28 which is obtained after cooking to an oxygen delignification reaction tower and adding sodium hydroxide and oxygen; and allowing delignification reaction of the high-hardness pulp in the oxygen delignification reaction tower to obtain pulp with hardness being potassium permanganate number of 10-14.
[0085] Preferably, the oxygen delignification is single stage and executed in the oxygen delignification reaction tower; the high-hardness pulp is at 95-100° C. and 0.9-1.2 MPa at an inlet of the reaction tower and at 100-105° C. and 0.2-0.6 MPa at an outlet; alkali used in the oxygen delignification treatment is 2-4% of bone dry pulp based on sodium hydroxide, and oxygen added is 20-40 kg for every ton of bone dry pulp; and the high-hardness pulp reacts in the reaction tower for 60-90 min.
[0086] The cooking comprises one of ammonium sulfite, anthraquinone-sodium hydroxide, sulfate or basic sodium sulfite methods:
in the ammonium sulfite cooking method, ammonium sulfite used is 9-13% of the bone dry raw material; in the anthraquinone-sodium hydroxide cooking method, alkali used is 9-15% of the bone dry raw material based on sodium hydroxide; and in the sulfate cooking method, alkali used is 8-11% of the bone dry raw material based on sodium hydroxide; and in the basic sodium sulfite cooking method, sodium hydroxide used is 11-15% of the bone dry raw material and sodium sulfite used is 2-6% of the bone dry raw material.
[0091] The washing step comprises:
(1 ) feeding the high-hardness pulp with concentration of 8-15% from an inlet of a press master, and pressing black liquor under the action of pressing force to obtain pressed pulp with concentration of 18-25%; in which the press master is preferably a single screw press master, a double screw press master or a double roll press master; and (2 ) washing the pressed pulp with one or both of black liquor with concentration of 3-6.2° Be′, pH at 8-8.3 at 70-80° C. and clean water at 70-80° C. in a vacuum pulp washer, a pressure pulp washer or a horizontal belt pulp washer.
[0094] In order to describe summary and technical schemes of the invention clearly, terms used in the invention are defined as follows, and in the case of inconsistency between definitions of any other literatures and the invention, definitions in the invention prevail as follows:
[0095] The unbleached straw pulp of the invention refers to straw pulp obtained from one or more combined raw materials of annual plants comprising, but not limited to, wheat straw, rice straw, cotton stalk, bagasse, giant reed and reed without any bleaching completely or straw pulp prepared from grass plants through oxygen delignification without other bleaching.
[0096] The unbleached paper product of the invention refers to the paper product mainly prepared by a conventional method from straw pulp which is prepared from grass plants as the raw material without any bleaching completely or the paper product mainly prepared by a conventional method from straw pulp which is prepared from grass plants as the raw material through oxygen delignification without other bleaching.
[0097] In the preparation method of the unbleached straw pulp of the invention, the prior art can be used for preparing for the grass material at first, that is, a conventional dry/wet method is used for preparing for the material to remove leaf, spike, grain, pith, kernel and other impurities, thus relieving load of the subsequent process and increasing mass of wheat straw pulp. The dry and wet material preparation can be performed by existing conventional equipment such as straw cutter, screening machine, dusting machined, wet washing and rubbing machine and oblique spiral dewaterer. The prepared and dewatered grass material can also be fine material and is bone dry grass without water in grass material, and the length of chopped straw is usually 15-30 mm, and the material preparation process is well known among those skilled in the art.
[0098] In the material preparation course of the invention, a hammer crusher can be used for dry material preparation, and the preparation course comprises:
(1 ) cutting and rubbing the grass material with the hammer crusher to obtain the cut and rubbed material;
[0100] The grass material is fed to the hammer crusher in the step, and the hammer crusher comprises a conveying and feeding segment, a crushing and rubbing segment and a scattering and discharging segment. The grass material is subject to extrusion effect, thus the grass material with round cross section is flattened to separate leaf, arista, kernel, grain, pith and other impurities from straw and then the grass material is discharged from an outlet of the hammer crusher. The discharged grass material is 20-50 mm long.
[0101] The hammer crusher of the invention is a hammer mill for existing material preparation. Speed of the hammer crusher is 500-800 rpm, the grass materials is fed to the hammer crusher at the speed of 0.5-1.3 m/s, and too low or too high feeding speed can cause a quantity of grass material not to be rubbed completely, thus affecting subsequent infiltration of the cooking liquor and further affecting quality of the straw pulp.
[0102] The grass material has a waxy layer on an outer layer and a pith layer inside stalk thereof; in a general material preparation method, when the outer layer is macerated in the cooking liquor, wax is removed rapidly, but the cooking liquor is difficult to infiltrate into the inner layer due to air existing in the inner layer of the stalk. The grass material is cut and rubbed by the hammer crusher, which benefits adequate maceration of the grass material, and high-quality straw pulp is easily obtained after the cooking.
(2 ) dedusting the cut and crushed material;
[0104] the cut and crushed material is dedusted for the reason that cut chopped straw contains dust, sandstone, grass blade, grass spike and other impurities, and most impurities are removed by dedusting treatment, thus chemical consumption for cooking can be reduced and cooking time can also be correspondingly reduced in the cooking process after the material preparation.
[0105] The dusting machine used in the dedusting treatment of the invention can be the dusting machine used for preparing for the grass material in the prior art, including roll dusting machine, double cone dusting machine and cyclone dusting machine, and the dusting machine is preferably the cyclone dusting machine. Air rate is 30000-38000 m 3 /h and air pressure is 210 mm water cylinder during dedusting by the cyclone dusting machine. Dust contained in the grass material can be largely removed under such condition, thus relieving load of subsequent cooking.
(3 ) Screening the dedusted material.
[0107] The dedusted grass material tends to carry impurities such as large chopped straw and powder, part of which are difficult to be infiltrated by the cooking liquor during cooking so as to produce undigested substances; although part of powder reacts with the cooking liquor, viscosity of the black liquor is increased, which affects cycle of the cooking liquor, causes uneven cooking and difficulty in operation and affects amount of the black liquor extracted from the paper pulp and washing quality of the pulp, thus the screening step is very important in the dry material preparation of the grass material.
[0108] The cylindrical sieve of the invention is that used for the dry material preparation of the grass materials in the prior art. The cylindrical sieve has a speed of 18-29 rpm and an inclination angle of 6-12° and is a double layer cylindrical sieve, side length of rectangular sieve pores of an internal sieve plate of the cylindrical sieve is 30-40 mm, and diameter of sieve pores of an external sieve plate is 4-6 mm; large chopped straw and other small impurities such as mud, sand and dust are screened in the screening process, thus ensuring clean paper pulp.
[0109] Removal rate of impurities of the grass material exceeds 90% after the dry material preparation method of the invention, but removal rate of impurities is 70% for a general dry material preparation method, which can reduce dust in the pulp, prepare clean pulp, achieve high yield 3-6% higher than that of the general method and lower production cost by 2-5% by the method of the invention.
[0110] The raw material can be macerated by the method of the invention before the cooking, the wheat straw material is macerated with maceration extract to attain liquor ratio of 1:2-4, insulated and mixed in a spiral macerator at 85° C. and normal pressure for more than 10 min, in which time for insulating and mixing at 85-95° C. is preferably 10-40 min. Therefore, the maceration extract is in full contact with the wheat straw material and the wheat straw material is macerated evenly and fully.
[0111] The maceration extract can be alkali solution with certain concentration, for example alkali solution containing alkali being 4% of the bone dry raw material by weight based on sodium hydroxide, and can also be mixture of the alkali solution and the black liquor which has a concentration of 11-14° Be′ (20° C.). The raw material is macerated to recycle heat and remaining alkali in the black liquor and reduce energy and resource consumption; maceration pretreatment of the raw material causes the black liquor which is extracted during heating and mainly contains parenchyma cells, hemicellulose and lignin to be separated and discharged for getting ready for the next cooking step. Maceration of the raw material belongs to a pretreatment process with the main purpose of facilitating the delignification reaction in a subsequent cooking process.
[0112] Grass pulping refers to properly removing lignin from the grass material by the action of the cooking liquor and retaining cellulose and hemicellulose as much as possible for facilitating papermaking. Actually, the lignin, cellulose, hemicellulose and other components in the raw material are subject to certain chemical changes, degradation and damage at different degrees under the action of high temperature in the cooking process, thus a change rule of the raw material in the cooking process must be studied to establish suitable cooking condition. In the pulping method of the invention, cooking is performed under a condition with cellulose and hemicellulose damage reduced as much as possible through systematic study on consumption and concentration of the cooking liquor, cooking and insulating time and cooking temperature, thus achieving the purposes of reducing production cost, saving energy source and improving pulping yield.
[0113] In the method of the invention, high-hardness pulp is obtained after cooking and has hardness being 16-28 potassium permanganate number equivalent to 24-50 Kappa number and beating degree of 10-24° SR; preferably, the high-hardness pulp has hardness being 18-27 potassium permanganate number equivalent to 29-48 Kappa number; most preferably, the high-hardness pulp has hardness being 20-25 potassium permanganate number equivalent to 34-42 Kappa number.
[0114] The high-hardness pulp prepared by the cooking in the invention is used as the raw material for preparing unbleached pulp. The preparation method by cooking in the prior art has problems of long cooking and insulating time, high cooking temperature and a large amount of cooking liquor used and long insulating time. But in the preparation method of the invention, the cooking liquor used is less and the cooking and insulating time is greatly shortened. In the cooking method of the invention, the cooking is performed under a condition with cellulose and hemicellulose damage reduced as much as possible through systematic study on consumption and concentration of the cooking liquor, cooking and insulating time and cooking temperature, thus achieving purposes of reducing production cost, saving energy source and improving pulping yield. Yield of the high-hardness pulp obtained by the cooking method is 58-68%.
[0115] In the preparation method of the invention, the obtained high-hardness pulp is kept at certain pressure which is 0.75 MPa and then blown to a blow tank after ending cooking. Diluent can be the black liquor used for the maceration above. At the moment, the high-hardness pulp in the blow tank has concentration of 8-15% and hardness being 16-28 potassium permanganate number equivalent to 26-50 Kappa number; the blow tank and the spiral press master are connected via a conveying pump, the conveying pump conveys the high-hardness pulp from the blow tank to the inlet of the spiral press master, the high-hardness pulp is fed from the inlet of the spiral press master and discharged from the outlet of the press master after being pressed, and concentration of the pulp discharged increases from 8-15% to 20-28%, and the pulp becomes high-concentration and high-hardness pulp at 70-80° C. Most black liquor is pressed out and stored in a black liquor tank while pressing the pulp. The press master used is the spiral press master for extracting the black liquor in the prior art, preferably a single spiral press master or a double spiral press master and a double roll press master with variable diameter and pitch.
[0116] As great pressing force is generated and temperature rises rapidly in the pulp pressing process while pressing pulp by the press master, fiber is forced to be separated, devillicated, fibrillated and bruised, a primary wall is damaged, the fiber absorbs enough energy and generates great stress inside and reaction performance of the high-hardness pulp is greatly improved. Meanwhile, the fiber is subject to fibrillation, epidermal organic substances and impurities in the fiber are dissolved in the black liquor and discharged from a liquor discharge tank, and fiber purity is greatly improved. Ash and impurities in the black liquor are also discharged along with the black liquor for getting fully ready for the next step. Most preferably, the press master of the invention is the spiral press master with variable diameter, and compressed pulp layers of the pulp within a slowly reducing space are unitedly dewatered internally and externally by the press master with variable diameter. After the selected single spiral press master with variable diameter of the invention presses the high-hardness pulp, beating degree of the high-hardness pulp does not change largely.
[0117] The double roll press master can also be used while pressing pulp, and double roll press master can be used in the same manner as the single spiral press master to minimize damages to the fiber, and as the double roll press master has a high black liquor extraction rate, water consumption in the subsequent washing process is greatly reduced and much less than that of the single spiral press master, and concentration of the high-hardness pulp exceeds 20% and reaches 25% at most after pressing.
[0118] In the preparation method of the invention, the high-hardness pulp obtained after the cooking or the high-concentration and high-hardness pulp obtained after the pressing is first diluted to 2.5-3.5% with the black liquor with concentration of 11-14° Be′ (20° C.) and then screened by a screening method in the prior art, for example hop screening method with a loss of 0.2-0.5% before washing the high-hardness pulp. Then, washing is performed by the vacuum pulp washer or the pressure pulp washer in the prior art. An objective of washing by the vacuum pulp washer is to easily form pressure difference between inside and outside of fibrocyte being cleaned, which is further beneficial to reach high clean degree in the washing process. In order to reach higher clean degree, washing can be performed once, twice or three times.
[0119] In the preparation method of the invention, pulp concentration is 9-11% after the washing, the pulp can be conveyed to a disintegrator by a spiral conveyer for disintegration, and the disintegrated pulp has beating degree of 26-28° SR and wet weight of 1.5-1.7 g at 65-70 ° C. The disintegrator is existing disintegration equipment such as deflaker, disc refiner or defibering machine. The disintegration can separate the fiber by rubbing and expose lignin between fiber and fiber, which benefits the following oxygen delignification step.
[0120] The high-hardness pulp obtained by the cooking or the pulp obtained after the disintegration or the pulp obtained after the washing is subject to oxygen delignification which refers to bleaching under the condition that alkali used is 2-4% of the bone dry pulp based on sodium hydroxide and oxygen added is 20-40 kg for every ton of pulp for 60-90 min. At the moment, hardness k value (potassium permanganate number) of the pulp falls to 11-13 equivalent to 12.5-17 Kappa number and beating degree is 32-36° SR. The oxygen delignification of the invention is preferably single stage and performed in an oxygen delignification reaction tower, and the high-hardness pulp is at 90-100° C. and 0.9-1.2 MPa at the inlet of the reaction tower and at 95-105° C. and 0.2-0.4 MPa at the outlet of the reaction tower. The main purpose of the single-stage oxygen delignification is to further ensure strength of the paper pulp, and the single-stage oxygen delignification has less degradation effect on cellulose relative to multistage oxygen delignification. In general, process parameters of the preferred single-stage oxygen delignification in the invention comprises low temperature and relatively long time with the purpose of more moderately performing the delignification reaction and avoiding the degradation of the cellulose as much as possible. Concentration of the high-hardness pulp is preferably 8-18% before the oxygen delignification treatment. The oxygen delignification is performed at medium concentration. The medium-concentration oxygen delignification has the main advantages of less investment, much more easy treatment of the pulp than high-concentration pulp due to successful medium and high concentration pulp mixing and pumping techniques, less equipment corrosion resulting from lower pulp concentration and no risk of burning in oxygen.
[0121] The unbleached pulp obtained from the steps has a breaking length of 5.0-7.5 km, tear strength of 230-280 mN, whiteness of 25-45% ISO, folding number of 40-90 and beating degree of 32-38° SR.
[0122] The invention has the following benefits:
(1 ) The unbleached pulp can avoid damage of chemicals used in the bleaching process to human, and the prepared unbleached paper product can not contain dioxins, adsorbable organic halide and other carcinogenic substances, thus producing no damage to human. (2 ) The unbleached straw pulp can reduce effects of the bleaching process on breaking length, tear strength and folding number, and different preparation methods generate very excellent performances of the prepared pulp, which can greatly improve quality of the unbleached paper product. (3 ) The unbleached paper product is prepared from the straw pulp as the raw material without any fluorescer, thus the prepared paper product can not be subject to secondary pollution of the substances, original properties of the paper product can be kept and no damage is produced to human. (4 ) As the preparation method of the unbleached straw pulp is improved, strength and other properties of the prepared straw pulp are greatly improved, the straw pulp can be mixed with a small amount of wood pulp or other papermaking pulp for preparing paper products and even can be directly manufactured into high-quality paper products.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Example 1
[0127] Wheat straw material is prepared by a hammer crusher and then put into a spherical digester, cooking liquor is added to the spherical digester, ammonium sulfite added is 9% of the bone dry raw material, liquor ratio is 1:3, and the mixture is heated to 110° C. for the first time, insulated at the temperature for 30 min, then relieved for 25 min, heated to 168° C. for 60 min for the second time and insulated for 90 min. The high-hardness pulp obtained after cooking has hardness of 22 equivalent to 35.5 Kappa number and beating degree of 11.6° SR and is diluted to 2.5% with diluted black liquor and then screened by a screening method in the prior art, for example hop screening method, with loss of 0.5%. The high-hardness pulp is washed by a vacuum pulp washer in the prior art. The high-hardness pulp with concentration of 10% obtained after washing is conveyed to a medium-concentration pulp pipe. The high-hardness pulp is conveyed to an oxygen delignification reaction tower via a medium-concentration pulp pump. The pulp is mixed with added oxygen of 20 kg for 1 t pulp and alkali solution with alkali content being 4% of the bone dry raw material based on sodium hydroxide in the pipe and heated by feeding steam to the pipe before being fed into the reaction tower. Then, the pulp is fully mixed in a mixer and then fed into the oxygen delignification reaction tower, magnesium sulfate is used as a protectant, magnesium sulfate added is 1% of the bone dry raw material, the inlet temperature is 95° C., the inlet pressure is 0.9 Mpa, the condition is kept 75 min to allow the pulp to receive sufficient delignification reaction, temperature is 100° C. and pressure is kept at 0.3 MPa at the top of the tower. The pulp is blown to a pulp chest and diluted to obtain the unbleached pulp after finishing treatment. The unbleached straw pulp has a breaking length of 5.0 km, folding number of 40, tear strength of 220 mN, whiteness of 40% ISO and beating degree of 34° SR. The unbleached straw pulp is beaten to a degree of 33° SR with wet weight of 2.1 g, and additionally prepared unbleached wood pulp is beaten to a degree of 20° SR with wet weight of 12 g.
[0128] Up to 65% of the beaten unbleached straw pulp and 35% of beaten unbleached wood pulp by weight are mixed evenly and manufactured to obtain the unbleached offset printing paper. The unbleached offset printing paper has an basis weight of 69.0 g/m 2 , opacity of 85%, breaking length of 3.9 km, whiteness of 49% ISO, transverse folding number of 19, and tear strength of 258 mN.
Example 2
[0129] Rice straw material is prepared by a hammer crusher and then put into a spherical batch cooker, cooking liquor is added to the spherical batch cooker, ammonium sulfite added is 13% of the bone dry raw material, liquor ratio is 1:4, and the mixture is heated to 120° C. for the first time, insulated at the temperature for 40 min, then relieved for 25 min, heated to 168° C. for 60 min for the second time and insulated for 90 min. The high-hardness pulp obtained after cooking has hardness of 16 equivalent to 23 Kappa number and beating degree of 23.4° SR and is diluted to 2.5% with diluted black liquor and then screened by a screening method in the prior art, for example, hop screening method, with loss of 0.2%. The high-hardness pulp is washed by a vacuum pulp washer in the prior art. The high-hardness pulp with concentration of 10% obtained after washing is heated to 70° C. and conveyed to a medium-concentration pulp pipe by a spiral conveyer. The pulp is subject to thermal refining in the medium-concentration pulp pipe to eliminate air and to be fluidized and then conveyed to an oxygen delignification reaction tower by a centrifugal medium-concentration pulp pump. The pulp is mixed with added oxygen of 20 kg for 1 t pulp and alkali solution with alkali content being 3.5% of the bone dry raw material based on sodium hydroxide in the pipe and heated by feeding steam to the pipe before being fed into the reaction tower. Then, the pulp is fully mixed in a mixer and then fed into the oxygen delignification reaction tower, magnesium sulfate is used as a protectant, magnesium sulfate added is 1% of the bone dry raw material, the inlet temperature is 95° C., the inlet pressure is 0.9 Mpa, the condition is kept 75 min to allow the pulp to receive sufficient delignification reaction, temperature is 100° C. and pressure is kept at 0.4 MPa at the top of the tower. The pulp is blown to a pulp chest and diluted to obtain the unbleached pulp after finishing treatment. The unbleached straw pulp has a breaking length of 6.8 km, folding number of 50, tear strength of 250 mN, whiteness of 41% ISO and beating degree of 36° SR.
[0130] Up to 70% of the unbleached straw pulp and 30% of unbleached wood pulp by weight are beaten at the beating concentration of 3.0% and 4.5% respectively in a double disc refiner, and quality standards for finished pulp obtained after beating are as follows: beating degree of 34° SR and wet weight of 1.8 g for the straw pulp and beating degree of 22° SR and wet weight of 10 g for the wood pulp. The unbleached wood pulp is that of the prior art and has a breaking length of 6.5 km, tear strength of 1000 mN, whiteness of 18% ISO and folding number of 1000.
[0131] The beaten pulp is mixed evenly and manufactured to obtain the unbleached offset printing paper. The manufacturing comprises manufacturing the finished pulp obtained after the beating and is performed in a multi-cylinder and long-wire paper machine.
[0132] The unbleached offset printing paper has an basis weight of 70.0 g/m 2 , opacity of 84%, breaking length of 4.9 km, whiteness of 52% ISO, transverse folding number of 22, and tear strength of 229 mN.
Example 3
[0133] Bagasse material is prepared conventionally by a dry method, has pith removed and then is put into a spherical digester, cooking liquor is added to the spherical digester, ammonium sulfite added is 11% of the bone dry raw material, liquor ratio is 1:2.5, and the mixture is heated to 130° C. for the first time, insulated at the temperature for 20 min, then relieved for 20 min, heated to 165° C. for 50 min for the second time and insulated for 70 min. High-hardness pulp obtained by cooking has hardness of 21 equivalent to 32 Kappa number and beating degree of 14.2° SR and is conveyed to a double spiral press master for extracting the black liquor in the prior art for pressing, the high-hardness pulp with concentration of 25% obtained after pressing is diluted to 2.5% with black liquor and then conveyed to the vacuum pulp washer for washing, and the obtained pulp is heated to 70° C. by a spiral conveyor and conveyed to a medium-concentration pulp pipe after concentration of the pulp reaches 10-13%. The pulp is subject to thermal refining in the medium-concentration pulp pipe to eliminate air and to be fluidized and then conveyed to an oxygen delignification reaction tower by a centrifugal medium-concentration pulp pump. The pulp is mixed with added oxygen of 30 kg for 1 t pulp and alkali solution with alkali content being 3% of the bone dry raw material based on sodium hydroxide in the pipe and heated by feeding steam to the pipe before being fed into the reaction tower. Then, the pulp is fully mixed in a mixer and then fed into the oxygen delignification reaction tower, magnesium sulfate is used as a protectant, magnesium sulfate added is 0.8% of the bone dry raw material, the inlet temperature is 98° C., the inlet pressure is 1.05 Mpa, the condition is kept 85 min to allow the pulp to receive sufficient delignification reaction, temperature is 102° C. and pressure is kept at 0.4 MPa at the top of the tower. The pulp is blown to a pulp chest and diluted to obtain the unbleached pulp after finishing treatment. The unbleached straw pulp has a breaking length of 6.0 km, folding number of 70, tear strength of 230 mN, whiteness of 40% ISO and beating degree of 35° SR.
[0134] Up to 85% of the unbleached straw pulp and 15% of unbleached wood pulp by weight are beaten at the beating concentration of 3.2% and 4.0% respectively in a double cylinder refiner, and quality standards for finished pulp obtained after beating are as follows: concentration of 3.2%, beating degree of 33° SR and wet weight of 2.0 g for straw pulp and concentration of 4.0%, beating degree of 18° SR and wet weight of 11 g for wood pulp. The beaten pulp is mixed evenly and manufactured to obtain the unbleached offset printing paper. The manufacturing is performed in multi-cylinder and short and long-wire paper machines.
[0135] The unbleached offset printing paper has an basis weight of 65.0 g/m 2 , opacity of 85%, breaking length of 5.5 km, whiteness of 48% ISO, transverse folding number of 28, and tear strength of 230 mN.
Example 4
[0136] Giant reed is prepared by a hammer crusher and then put into a spherical digester, cooking liquor is added to the spherical digester, ammonium sulfite added is 11% of the bone dry raw material, liquor ratio is 1:3, and the mixture is heated to 140° C. for the first time, insulated at the temperature for 40 min, then relieved for 20 min, heated to 175° C. for 60 min for the second time and insulated for 90 min. High-hardness pulp obtained after cooking has hardness of 19 equivalent to 28.5 Kappa number and beating degree of 15.6° SR and is conveyed to a single spiral press master with variable diameter for extracting the black liquor in the prior art for pressing, the high-hardness pulp with concentration of 26% is obtained after pressing, the pulp from the press master is diluted to 2.5-3.0% with diluted black liquor and then conveyed to a hop sieve for coarse pulp screening with hop sieve loss of 0.2%, the pulp is cleared off impurities by a high-concentration deslagging machine with loss of 0.1%, the pulp obtained after deslagging is fed into a horizontal belt pulp washer for washing, pulp concentration is 2.0% while washing, the pulp from the pulp washer has concentration of 9%, temperature is kept at 70° C. during the washing process, the pulp is conveyed to a disintegrator for disintegration, beating degree of the giant reed is 24° SR and 27° SR before and after the disintegration, and the pulp is heated to 70° C. by a spiral conveyor and conveyed to a medium-concentration pulp pipe after concentration of the pulp is adjusted to 10%. The pulp is subject to thermal refining in the medium-concentration pulp pipe to eliminate air and to be fluidized and then conveyed to an oxygen delignification reaction tower by a centrifugal medium-concentration pulp pump. The pulp is mixed with added oxygen of 30 kg for 1 t pulp and alkali solution with alkali content being 4% of the bone dry raw material based on sodium hydroxide in the pipe before being fed into the reaction tower and heated by feeding steam to the pipe. Then, the pulp is fully mixed in a mixer and then fed into the oxygen delignification reaction tower, magnesium sulfate is used as a protectant, magnesium sulfate added is 1% of the bone dry raw material, the inlet temperature is 102° C., the inlet pressure is 1.2 Mpa, the condition is kept 90 min to allow the pulp to receive sufficient delignification reaction, temperature is 105° C. and pressure is kept at 0.5 MPa at the top of the tower. The pulp is blown to a pulp chest and diluted to obtain the unbleached pulp after finishing treatment. The unbleached straw pulp has a breaking length of 7.5 km, folding number of 80, tear strength of 280 mN, whiteness of 37% ISO and beating degree of 33° SR.
[0137] Up to 50% of the unbleached straw pulp and 50% of unbleached wood pulp by weight are beaten in a cylindrical refiner at beating concentration of 3.8%, beating pressure of 0.20 MPa and beating current of 62 A respectively, and then beaten in a double disc refiner, beating concentration is 3.4%, beating degree is 35° SR and wet weight is 2.2 g for the straw pulp, and beating concentration is 4.5%, beating degree is 19° SR and wet weight is 12 g for the wood pulp. The unbleached wood pulp is that of the prior art.
[0138] The beaten pulp is manufactured to obtain the unbleached food wrap paper. The manufacturing comprises manufacturing the finished pulp obtained after beating and is performed in a single round wire, single drying cylinder and single felt toilet paper machine, and the unbleached food wrap paper is obtained after the manufacturing. The unbleached food wrap paper has an basis weight of 60.0 g/m 2 , thickness of 79.0 μm, smoothness of 47 S for the front side and 39 S for the reverse side, whiteness of 20% ISO, opacity of 97.6%, breaking length of 6.8 km, transverse folding number of 150, transverse tear strength of 600 mN and water content of 5.2%.
Example 5
[0139] Giant reed and reed are prepared by a hammer crusher at a mass ratio of 1:4 and then filled in hot black liquor at 135° C. into a cooker by a filler at liquor ratio of 1:7, the cooker cover is closed after the cooker is full, cooking liquor at 145° C. is added to the cooker, alkali used is 13% of the bone dry raw material based on sodium hydroxide, anthraquinone added is 0.5% of the bone dry raw material, the black liquor and air in the filler are discharged, pressure is increased to 0.6 MPa, a cooking liquor circulating pump and a tubular heater of the cooker are started to heat the cooking liquor to 155° C., and heating and insulating last 160 min. The hot black liquor is exchanged by diluted black liquor and conveyed to a hot black liquor tank, high-hardness pulp obtained after cooking has hardness of 20 equivalent to 30 Kappa number and beating degree of 15° SR and concentration adjusted to 18% and is conveyed to a disc refiner for disintegration, washed by a conventional washing method, then heated to 70° C. and conveyed to a medium-concentration pulp pipe by a spiral conveyer. The pulp is subject to thermal refining in the medium-concentration pulp pipe to eliminate air and to be fluidized and then conveyed to an oxygen delignification reaction tower by a centrifugal medium-concentration pulp pump. The pulp is mixed with added oxygen of 35 kg for 1 t pulp and alkali solution with alkali content being 2.5% of the bone dry raw material based on sodium hydroxide in the pipe and heated by feeding steam to the pipe before being fed into the reaction tower. Then, the pulp is fully mixed in a mixer and then fed into the oxygen delignification reaction tower, magnesium sulfate is used as a protectant, magnesium sulfate added is 1% of the bone dry raw material, the inlet temperature is 100° C., the inlet pressure is 1.2 Mpa, the condition is kept 80 min to allow the pulp to receive sufficient delignification reaction, temperature is 105° C. and pressure is kept at 0.4 MPa at the top of the tower. The pulp is blown to a pulp chest and diluted to obtain the unbleached pulp after finishing treatment. The unbleached straw pulp has a breaking length of 7.0 km, folding number of 60, tear strength of 240 mN, whiteness of 37% ISO and beating degree of 37° SR.
[0140] Up to 60% of the unbleached straw pulp and 40% of unbleached wood pulp by weight are prepared and respectively beaten in a cylindrical refiner at beating concentration of 3.8%, beating pressure of 0.20 MPa and beating current of 65 A, and then beaten in a double disc refiner at beating concentration of 3.3%, beating pressure of 0.15 MPa and beating current of 45 A, and the quality standards for finished pulp obtained after beating are as follows: beating degree is 48° SR and wet weight is 2.8 g. The unbleached wood pulp is that of the prior art and has a breaking length of 7 km, tear strength of 1000 mN, whiteness of 20% ISO and folding number above 1000. The unbleached straw pulp has beating degree of 36° SR and wet weight of 2.3 g, and the unbleached wood pulp has beating degree of 20° SR and wet weight of 12 g.
[0141] The beaten pulp is mixed evenly and manufactured to obtain the unbleached food wrap paper. The unbleached food wrap paper has an basis weight of 45 g/m 2 , thickness of 79.0 m, smoothness of 45 S for the front side and 36 S for the reverse side, whiteness of 45% ISO, opacity of 97.6%, breaking length of 5.8 km, transverse folding number of 170, transverse tear strength of 550 mN and water content of 5.3%.
Example 6
[0142] Giant reed is prepared by a hammer crusher and then put into a spherical digester, cooking liquor is added to the spherical digester, ammonium sulfite added is 9% of the bone dry raw material, anthraquinone added is 0.8%, liquor ratio is 1:4, and the mixture is heated to 110° C. for the first time, insulated at the temperature for 40 min, then relieved for 30 min, heated to 173° C. for 50 min for the second time and insulated for 60 min. High-hardness pulp obtained after cooking has hardness of 20 equivalent to 30.7 Kappa number and beating degree of 12.5° SR and is conveyed to a single spiral press master with variable diameter for extracting the black liquor in the prior art for pressing, and the high-hardness pulp with concentration of 20% obtained after pressing is washed by a conventional washing method, e.g. a pressure washer, then conveyed to a disc disintegrator for disintegration, heated to 70° C. and conveyed to a medium-concentration pulp pipe by a spiral conveyor. The pulp is subject to thermal refining in the medium-concentration pulp pipe to eliminate air and to be fluidized and then conveyed to an oxygen delignification reaction tower by a centrifugal medium-concentration pulp pump. The pulp is mixed with added oxygen of 20 kg for 1 t pulp and alkali solution with alkali content being 4% of the bone dry raw material based on sodium hydroxide in the pipe and heated by feeding steam to the pipe before being fed into the reaction tower. Then, the pulp is fully mixed in a mixer and then fed into the oxygen delignification reaction tower, magnesium sulfate is used as a protectant, magnesium sulfate added is 1% of the bone dry raw material, the inlet temperature is 95° C., the inlet pressure is 0.9 Mpa, the condition is kept 70 min to allow the pulp to receive sufficient delignification reaction, temperature is 100° C. and pressure is kept at 0.3 MPa at the top of the tower. The pulp is blown to a pulp chest and diluted to obtain the unbleached pulp after finishing treatment. The unbleached straw pulp has a breaking length of 5.8 km, folding number of 55, tear strength of 260 mN, whiteness of 40% ISO and beating degree of 38° SR.
[0143] Up to 55% of the unbleached straw pulp and 45% of unbleached wood pulp by weight are respectively beaten in a double disc refiner, the beating degree of the reed pulp is 3.5% and that of the wood pulp is 4.5%, and quality standards for finished pulp obtained after beating are as follows: beating degree of 35° SR and wet weight of 2.0 g for the reed pulp and beating degree of 20° SR and wet weight of 12 g for the wood pulp. The unbleached wood pulp is unbleached sulfate softwood pulp of the prior art and has a breaking length of 5.0 km, tear strength of 1 100 mN, whiteness of 18% ISO, folding number above 1000 and beating degree of 39° SR.
[0144] The beaten pulp is manufactured to obtain the unbleached food wrap paper. The unbleached food wrap paper has an basis weight of 51.5 g/m 2 , thickness of 75.0 pm, smoothness of 48 S for the front side and 36 S for the reverse side, whiteness of 40% ISO, opacity of 96.8%, breaking length of 3.2 km, transverse folding number of 140, transverse tear strength of 380 mN and water content of 5.8%.
Example 7
[0145] Cotton stalk is prepared by a hammer crusher and then put into a spherical digester, cooking liquor is added to the spherical digester, alkali used is 8% of the bone dry raw material based on sodium hydroxide, sulfidity is 8%, liquor ratio is 1:2, and the mixture is heated to 110° C. for the first time, insulated at the temperature for 40 min, then relieved for 25 min, heated to 166° C. for 45 min for the second time and insulated for 75 min. High-hardness pulp obtained by cooking has hardness of 22 equivalent to 35 Kappa number and beating degree of 11.6° SR and is conveyed to a deflaker for disintegration and then to a double roll press master for extracting the black liquor in the prior art for pressing, the high-hardness pulp with concentration of 32% obtained after pressing is diluted to 2.5% with black liquor and washed by a conventional washing method after deslagging, concentration of pulp after washing is adjusted to 15%, and then the pulp is heated to 70° C. and conveyed to a medium-concentration pulp pipe by a spiral conveyor. The pulp is subject to thermal refining in the medium-concentration pulp pipe to eliminate air and to be fluidized and then conveyed to an oxygen delignification reaction tower by a centrifugal medium-concentration pulp pump. The pulp is mixed with added oxygen of 20 kg for 1 t pulp and alkali solution with alkali content being 3% of the bone dry raw material based on sodium hydroxide in the pipe and heated by feeding steam to the pipe before being fed into the reaction tower. Then, the pulp is fully mixed in a mixer and then fed into the oxygen delignification reaction tower, magnesium sulfate is used as a protectant, magnesium sulfate added is 1% of the bone dry raw material, the inlet temperature is 95° C., the inlet pressure is 0.9 Mpa, the condition is kept 90 min to allow the pulp to receive sufficient delignification reaction, temperature is 100° C. and pressure is kept at 0.4 MPa at the top of the tower. The pulp is blown to a pulp chest and diluted to obtain the unbleached pulp after finishing treatment. The unbleached straw pulp has a breaking length of 4.3 km, folding number of 70, tear strength of 275 mN, whiteness of 42% ISO and beating degree of 34° SR.
[0146] Up to 80% of the unbleached straw pulp and 20% of unbleached wood pulp by weight are respectively beaten in a double disc refiner, the beating degree of the cotton stalk is 3.5% and that of the wood pulp is 4.5%, and quality standards for finished pulp obtained after beating are as follows: beating degree of 55° SR and wet weight of 2.0 g for the reed pulp and beating degree of 48° SR and wet weight of 2.6 g for the wood pulp. The unbleached wood pulp is unbleached sulfate softwood pulp of the prior art and has a breaking length of 5.0 km, tear strength of 1100 mN, whiteness of 18% ISO, folding number above 1000 and beating degree of 39° SR.
[0147] The beaten pulp is manufactured to obtain the unbleached duplicating paper. The unbleached duplicating paper has an basis weight of 60.0 g/m 2 , transverse and longitudinal mean breaking length of 4.51 mm, longitudinal stiffness of 112 mN, transverse stiffness of 72 mN and whiteness of 44.7% ISO.
Example 8
[0148] Rice straw and wheat straw are prepared by a dry method using a hammer crusher at a mass ratio of 1:3 and then put into a spherical digester, cooking liquor is added to the spherical digester, alkali used is 11% of the bone dry raw material based on sodium hydroxide, sulfidity is 5%, liquor ratio is 1:4, and the mixture is heated to 110° C. for the first time, insulated at the temperature for 20 min, then relieved for 30 min, heated to 168° C. for 40 min for the second time and insulated for 90 min
[0149] High-hardness pulp obtained after cooking has hardness of 19 equivalent to 29 Kappa number and beating degree of 14.3° SR and is conveyed to a conventional single spiral press master with variable diameter for extracting the black liquor for pressing, the pulp from the press master is diluted to 3.0% with diluted black liquor, then conveyed to a hop sieve for coarse pulp screening with hop sieve loss of 0.2% and delagged by a high-concentration slag separator with loss of 0.1%, the pulp obtained after deslagging is fed into a horizontal belt pulp washer for washing, pulp concentration is 3.0% while washing, the pulp from the pulp washer has concentration of 9%, temperature is kept at 70° C. during the washing process, and the pulp is conveyed to a deflaker for disintegration, the pulp is subject to thermal refining in a medium-concentration pulp pipe to eliminate air and to be fluidized and then conveyed to an oxygen delignification reaction tower by a centrifugal medium-concentration pulp pump. The pulp is mixed with added oxygen of 20 kg for 1 t pulp and alkali solution with alkali content being 4% of the bone dry raw material based on sodium hydroxide in the pipe and heated by feeding steam to the pipe before being fed into the reaction tower. Then, the pulp is fully mixed in a mixer and then fed into the oxygen delignification reaction tower, magnesium sulfate is used as a protectant, magnesium sulfate added is 1% of the bone dry raw material, the inlet temperature is 95° C., the inlet pressure is 0.9 Mpa, the condition is kept 75 min to allow the pulp to receive sufficient delignification reaction, temperature is 100° C. and pressure is kept at 0.3 MPa at the top of the tower. The pulp is blown to a pulp chest and diluted to obtain the unbleached pulp after finishing treatment. The unbleached straw pulp has a breaking length of 7.2 km, folding number of 45, tear strength of 250 mN, whiteness of 42% ISO and beating degree of 33° SR.
[0150] Up to 50% of the unbleached straw pulp and 50% of unbleached wood pulp by weight are respectively beaten in a cylindrical refiner at beating concentration of 3.8%, beating pressure of 0.20 MPa and beating current of 62 A, and then beaten in a double disc refiner at beating concentration of 3.4%, beating pressure of 0.20 MPa and beating current of 60 A, and quality standards for the finished pulp after beating are as follows: beating degree of 48° SR and wet weight of 3.2 g. The unbleached wood pulp is that of the prior art, comprises unbleached sulfate softwood pulp, unbleached sulfite softwood pulp, etc. and has a breaking length of 6.5 km, tear strength of 1000 mN, whiteness of 20% ISO, folding number above 1000 and beating degree of 38° SR.
[0151] The beaten pulp is manufactured to obtain the unbleached duplicating paper. The unbleached duplicating paper has an basis weight of 65.0 g/m 2 , transverse and longitudinal mean breaking length of 7.5 km, longitudinal stiffness of 82 mN, transverse stiffness of 55 mN and whiteness of 41.8% ISO.
Example 9
[0152] Rice straw is prepared by a dry method using a hammer crusher and then put into a spherical digester, cooking liquor is added to the spherical digester, alkali used is 15% of the bone dry raw material based on sodium hydroxide, liquor ratio is 1:3, anthraquinone added is 0.6% of the bone dry raw material, and the mixture is heated to 120° C. for the first time, insulated at the temperature for 20 min, then relieved for 20-30 min, heated to 168° C. for 40 min for the second time and insulated for 90 min. High-hardness pulp obtained after cooking has hardness of 18 equivalent to 27 Kappa number and beating degree of 17° SR and is conveyed to a conventional single spiral press master with variable diameter for extracting the black liquor for pressing, the pulp from the press master is diluted to 2.5% with diluted black liquor, then conveyed to a hop sieve for coarse pulp screening with hop sieve loss of 0.2% and delagged by a high-concentration slag separator with loss of 0.1%, the pulp obtained after deslagging is fed into a horizontal belt pulp washer for washing, pulp concentration is 3.0% while washing, the pulp from the pulp washer has concentration of 9%, temperature is kept at 68-70° C. during the washing process, and the pulp is conveyed to a deflaker for disintegration, heated to 70° C. and conveyed to a medium-concentration pulp pipe by a spiral conveyor after adjusting concentration. The pulp is subject to thermal refining in the medium-concentration pulp pipe to eliminate air and to be fluidized and then conveyed to an oxygen delignification reaction tower by a centrifugal medium-concentration pulp pump. The pulp is mixed with added oxygen of 20 kg for 1 t pulp and alkali solution with alkali content being 4% of the bone dry raw material based on sodium hydroxide in the pipe and heated by feeding steam to the pipe before being fed into the reaction tower. Then, the pulp is fully mixed in a mixer and then fed into the oxygen delignification reaction tower, magnesium sulfate is used as a protectant, magnesium sulfate added is 1% of the bone dry raw material, the inlet temperature is 102° C., the inlet pressure is 1.12 Mpa, the condition is kept 70 min to allow the pulp to receive sufficient delignification reaction, temperature is 104° C. and pressure is kept at 0.5 MPa at the top of the tower. The pulp is blown to a pulp chest and diluted to obtain the unbleached pulp after finishing treatment. The unbleached straw pulp has a breaking length of 4.4 km, folding number of 65, tear strength of 245 mN, whiteness of 37% ISO and beating degree of 34° SR.
[0153] Up to 70% of the unbleached straw pulp and 30% of unbleached wood pulp by weight are respectively beaten in a double disc refiner, the beating concentration of the straw pulp is 3.2% and that of the wood pulp is 4.5%, and quality standards for finished pulp obtained after beating are as follows: beating degree of 55° SR and wet weight of 2.0 g for the straw pulp and beating degree of 48 ° SR and wet weight of 2.0 g for the wood pulp. The unbleached wood pulp is unbleached sulfate hardwood pulp of the prior art.
[0154] The beaten pulp is manufactured to obtain the unbleached duplicating paper.
[0155] The unbleached duplicating paper has an basis weight of 72.0 g/m 2 , transverse and longitudinal mean breaking length of 6.2 km, longitudinal stiffness of 90 mN, transverse stiffness of 56 mN and whiteness of 35.0% ISO.
Example 10
[0156] Rice straw and wheat straw are prepared by a dry method using a hammer crusher at a mass ratio of 1:3 and then put into a spherical digester, cooking liquor is added to the spherical digester, alkali used is 11% of the bone dry raw material based on sodium hydroxide, sulfidity is 5%, liquor ratio is 1:4, and the mixture is heated to 110° C. for the first time, insulated at the temperature for 20 min, then relieved for 30 min, heated to 168° C. for 40 min for the second time and insulated for 90 min.
[0157] High-hardness pulp obtained after cooking has hardness of 19 equivalent to 29 Kappa number and beating degree of 14.3° SR and is conveyed to a conventional single spiral press master with variable diameter for extracting the black liquor for pressing, the pulp from the press master is diluted to 3.0% with diluted black liquor, then conveyed to a hop sieve for coarse pulp screening with hop sieve loss of 0.2% and delagged by a high-concentration slag separator with loss of 0.1%, the pulp obtained after deslagging is fed into a horizontal belt pulp washer for washing, pulp concentration is 3.0% while washing, the pulp from the pulp washer has concentration of 9%, temperature is kept at 70° C. during the washing process, and the pulp is conveyed to a deflaker for disintegration, the pulp is subject to thermal refining in a medium-concentration pulp pipe to eliminate air and to be fluidized and then conveyed to an oxygen delignification reaction tower by a centrifugal medium-concentration pulp pump. The pulp is mixed with added oxygen of 20 kg for 1 t pulp and alkali solution with alkali content being 4% of the bone dry raw material based on sodium hydroxide in the pipe and heated by feeding steam to the pipe before being fed into the reaction tower. Then, the pulp is fully mixed in a mixer and then fed into the oxygen delignification reaction tower, magnesium sulfate is used as a protectant, magnesium sulfate added is 1% of the bone dry raw material, the inlet temperature is 95° C., the inlet pressure is 0.9 Mpa, the condition is kept 75 min to allow the pulp to receive sufficient delignification reaction, temperature is 100° C. and pressure is kept at 0.3 MPa at the top of the tower. The pulp is blown to a pulp chest and diluted to obtain the unbleached pulp after finishing treatment. The unbleached straw pulp has a breaking length of 7.2 km, folding number of 45, tear strength of 250 mN, whiteness of 42% ISO and beating degree of 33° SR.
[0158] The unbleached straw pulp is beaten at the beating degree of 30° SR with wet weight of 2.3 g.
[0159] The beaten pulp is mixed evenly and the subject to post-treatment to obtain the unbleached lunch box. The post-treatment comprises adding 1.1% of an oil proofing agent, 3.3% of a water repellent and 0.15% of a catcher and drying at 0.055 MP and 180° C. for 75 s. The obtained unbleached lunch box completely meets requirements for Grade A products in GB 18006.1-1999.
Example 11
[0160] Rice straw is prepared by a dry method using a hammer crusher and then put into a spherical digester, cooking liquor is added to the spherical digester, alkali used is 15% of the bone dry raw material based on sodium hydroxide, liquor ratio is 1:3, anthraquinone added is 0.6% of the bone dry raw material, and the mixture is heated to 120° C. for the first time, insulated at the temperature for 20 min, then relieved for 20-30 min, heated to 168° C. for 40 min for the second time and insulated for 90 min. High-hardness pulp obtained after cooking has hardness of 18 equivalent to 27 Kappa number and beating degree of 17° SR and is conveyed to a conventional single spiral press master with variable diameter for extracting the black liquor for pressing, the pulp from the press master is diluted to 2.5% with diluted black liquor, then conveyed to a hop sieve for coarse pulp screening with hop sieve loss of 0.2% and delagged by a high-concentration slag separator with loss of 0.1%, the pulp obtained after deslagging is fed into a horizontal belt pulp washer for washing, pulp concentration is 3.0% while washing, the pulp from the pulp washer has concentration of 9%, temperature is kept at 68-70° C. during the washing process, and the pulp is conveyed to a deflaker for disintegration, heated to 70° C. and conveyed to a medium-concentration pulp pipe by a spiral conveyor after adjusting concentration. The pulp is subject to thermal refining in a medium-concentration pulp pipe to eliminate air and to be fluidized and then conveyed to an oxygen delignification reaction tower by a centrifugal medium-concentration pulp pump. The pulp is mixed with added oxygen of 20 kg for 1 t pulp and alkali solution with alkali content being 4% of the bone dry raw material based on sodium hydroxide in the pipe and heated by feeding steam to the pipe before being fed into the reaction tower. Then, the pulp is fully mixed in a mixer and then fed into the oxygen delignification reaction tower, magnesium sulfate is used as a protectant, magnesium sulfate added is 1% of the bone dry raw material, the inlet temperature is 102° C., the inlet pressure is 1.12 Mpa, the condition is kept 70 min to allow the pulp to receive sufficient delignification reaction, temperature is 104° C. and pressure is kept at 0.5 MPa at the top of the tower. The pulp is blown to a pulp chest and diluted to obtain the unbleached pulp after finishing treatment. The unbleached pulp has a breaking length of 4.4 km, folding number of 65, tear strength of 245 mN, whiteness of 37% ISO and beating degree of 34° SR.
[0161] Up to 70% of the unbleached straw pulp and 30% of unbleached wood pulp are respectively beaten, the beating degree is 31° SR and wet weight is 2.2 g for the unbleached straw pulp, and the beating degree is 20° SR and wet weight is 10 g for the unbleached wood pulp.
[0162] The beaten pulp is mixed evenly and subject to post-treatment to obtain the unbleached lunch box. The post-treatment comprises adding 1.1% of an oil proofing agent, 3.3% of a water repellent and 0.15% of a catcher and drying at 0.05 MP and 178° C. for 78 s. The obtained unbleached lunch box completely meets requirements for Grade A products in GB 18006.1-1999.
Example 12
[0163] Giant reed is prepared by a conventional dry method using a hammer crusher and then put into a spherical digester, cooking liquor is added to the spherical digester, alkali used is 11% of the bone dry raw material based on sodium hydroxide, anthraquinone added is 0.8%, liquor ratio is 1:4, and the mixture is heated to 130° C. for the first time, insulated at the temperature for 40 min, then relieved for 30 min, heated to 173° C. for 60 min for the second time and insulated for 60 min. High=hardness pulp obtained after cooking has hardness of 25 equivalent to 45 Kappa number and beating degree of 12° SR and is conveyed to a single spiral press master with variable diameter for extracting the black liquor in the prior art for pressing, the high-hardness pulp with concentration of 20% obtained after pressing is conveyed to a hop sieve for coarse pulp screening with hop sieve loss of 0.2% and delagged by a high-concentration slag separator with loss of 0.1%, the pulp obtained after deslagging is fed into a horizontal belt pulp washer for washing, pulp concentration is 2.0% while washing, the pulp from the pulp washer has concentration of 9%, temperature is kept at 68-70° C. during the washing process, and the pulp is heated to 70° C. and conveyed to a medium-concentration pulp pipe by a spiral conveyor after adjusting concentration. The pulp is subject to thermal refining in a medium-concentration pulp pipe to eliminate air and to be fluidized and then conveyed to an oxygen delignification reaction tower by a centrifugal medium-concentration pulp pump. The pulp is mixed with added oxygen of 20 kg for it pulp and alkali solution with alkali content being 4% of the bone dry raw material based on sodium hydroxide in the pipe and heated by feeding steam to the pipe before being fed into the reaction tower. Then, the pulp is fully mixed in a mixer and then fed into an oxygen delignification reaction tower, magnesium sulfate is used as a protectant, magnesium sulfate added is 1% of the bone dry raw material, the inlet temperature is 102° C., the inlet pressure is 1.12 Mpa, the condition is kept 75 min to allow the pulp to receive sufficient delignification reaction, temperature is 104° C. and pressure is kept at 0.5 MPa at the top of the tower. The pulp is blown to a pulp chest and diluted to obtain the unbleached pulp after finishing treatment. The unbleached straw pulp has a breaking length of 5.0 km, folding number of 69, tear strength of 255 mN, whiteness of 42% ISO and beating degree of 33° SR.
[0164] Up to 70% of the unbleached straw pulp and 30% of unbleached wood pulp are respectively beaten, the beating degree is 32° SR and wet weight is 2.3 g for the unbleached straw pulp, and the beating degree is 20° SR and wet weight is 12 g for the unbleached wood pulp.
[0165] The beaten pulp is mixed evenly and subject to post-treatment to obtain the unbleached lunch box. The post-treatment comprises adding 1.2% of an oil proofing agent, 3% of a water repellent and 0.15% of a catcher and drying at 0.055 MP and 175° C. for 80 s.
[0166] The obtained unbleached lunch box completely meet requirements for Grade A products in GB 18006.1-1999.
Example 13
[0167] Wheat straw material is prepared by a hammer crusher and then put into a spherical digester, cooking liquor is added to the spherical digester, ammonium sulfite added is 9% of the bone dry raw material, liquor ratio is 1:3, and the mixture is heated to 110° C. for the first time, insulated at the temperature for 30 min, then relieved for 25 min, heated to 168° C. for 60 min for the second time and insulated for 90 min. The high-hardness pulp obtained after cooking has hardness of 22 equivalent to 35.5 Kappa number and beating degree of 11.6° SR and is diluted to 2.5% with diluted black liquor and then screened by a screening method in the prior art, for example, hop screening method with loss of 0.5%.The high-hardness pulp is washed by a vacuum pulp washer in the prior art. The high-hardness pulp with concentration of 10% obtained after washing is conveyed to a medium-concentration pulp pipe. The high-hardness pulp is conveyed to an oxygen delignification reaction tower via a medium-concentration pulp pump. The pulp is mixed with added oxygen of 20 kg for 1 t pulp and alkali solution with alkali content being 4% of the bone dry raw material based on sodium hydroxide in the pipe and heated by feeding steam to the pipe before being fed into the reaction tower. Then, the pulp is fully mixed in a mixer and then fed into the oxygen delignification reaction tower, magnesium sulfate is used as a protectant, magnesium sulfate added is 1% of the bone dry raw material, the inlet temperature is 95° C., the inlet pressure is 0.9 Mpa, the condition is kept 75 min to allow the pulp to receive sufficient delignification reaction, temperature is 100° C. and pressure is kept at 0.3 MPa at the top of the tower. The pulp is blown to a pulp chest and diluted to obtain the unbleached pulp after finishing treatment. The unbleached straw pulp has a breaking length of 5.0 km, folding number of 40, tear strength of 220 mN, whiteness of 40% ISO and beating degree of 34° SR. The unbleached straw pulp is beaten, and quality standards for the finished pulp obtained after beating are as follows: beating degree of 45° SR and wet weight of 2.8 g.
[0168] The beaten pulp is manufactured to obtain the unbleached towel paper. The manufacturing is performed in a single cylinder and long wire paper machine.
[0169] The unbleached towel paper has an basis weight of 23.0 g/m 2 , transverse suction range of 66 mm/100 s, longitudinal wet tensile strength of 36 N/m and whiteness of 41.5% ISO.
Example 14
[0170] Rice straw material is prepared by a dry method using a hammer crusher and then put into a spherical batch cooker, cooking liquor is added to the spherical batch cooker, ammonium sulfite added is 13% of the bone dry raw material, liquor ratio is 1:4, and the mixture is heated to 120° C. for the first time, insulated at the temperature for 40 min, then relieved for 25 min, heated to 168° C. for 60 min for the second time and insulated for 90 min. The high-hardness pulp obtained after cooking has hardness of 16 equivalent to 23 Kappa number and beating degree of 23.4° SR and is diluted to 2.5% with diluted black liquor and then screened by a screening method in the prior art, for example, hop screening method with loss of 0.2%. The high-hardness pulp is washed by a vacuum pulp washer in the prior art. The high-hardness pulp with concentration of 10% obtained after washing is heated to 70° C. and conveyed to a medium-concentration pulp pipe by a spiral conveyer. The pulp is subject to thermal refining in a medium-concentration pulp pipe to eliminate air and to be fluidized and then conveyed to an oxygen delignification reaction tower by a centrifugal medium-concentration pulp pump. The pulp is mixed with added oxygen of 20 kg for 1 t pulp and alkali solution with alkali content being 3.5% of the bone dry raw material based on sodium hydroxide in the pipe and heated by feeding steam to the pipe before being fed into the reaction tower. Then, the pulp is fully mixed in a mixer and then fed into the oxygen delignification reaction tower, magnesium sulfate is used as a protectant, magnesium sulfate added is 1% of the bone dry raw material, the inlet temperature is 95° C., the inlet pressure is 0.9 Mpa, the condition is kept 75 min to allow the pulp to receive sufficient delignification reaction, temperature is 100° C. and pressure is kept at 0.4 MPa at the top of the tower. The pulp is blown to a pulp chest and diluted to obtain the unbleached pulp after finishing treatment. The unbleached straw pulp has a breaking length of 6.8 km, folding number of 50, tear strength of 250 mN, whiteness of 45% ISO and beating degree of 36° SR.
[0171] Up to 70% of the unbleached straw pulp and 30% of unbleached wood pulp by weight are beaten at the beating concentration of 3.0% and 4.5% respectively in a double disc refiner, and quality standards for finished pulp obtained after beating are as follows: beating degree of 50° SR and wet weight of 1.8 g for the straw pulp and beating degree of 46° SR and wet weight of 1.2 g for the wood pulp. The unbleached hardwood pulp has a breaking length of 6.5 km, tear strength of 1000 mN, whiteness of 18% ISO, folding number of 1000 and beating degree of 38° SR.
[0172] The beaten pulp is mixed evenly and manufactured to obtain the unbleached towel paper. The manufacturing is performed in a double cylinder and long wire paper machine The unbleached towel paper has an basis weight of 38.2 g/m 2 , transverse suction range of 60 mm/100 s, longitudinal wet tensile strength of 30 N/m and whiteness of 38% ISO.
Example 15
[0173] Bagasse material is prepared conventionally by a dry method, has pith removed and then is put into a spherical digester, cooking liquor is added to the spherical digester, ammonium sulfite added is 11% of the bone dry raw material, liquor ratio is 1:2.5, and the mixture is heated to 130° C. for the first time, insulated at the temperature for 20 min, then relieved for 20 min, heated to 165° C. for 50 min for the second time and insulated for 70 min. High-hardness pulp obtained by cooking has hardness of 21 equivalent to 32 Kappa number and beating degree of 14.2° SR and is conveyed to a double spiral press master for extracting the black liquor in the prior art for pressing, the high-hardness pulp with concentration of 25% obtained after pressing is diluted to 2.5% with black liquor and then conveyed to a vacuum pulp washer for washing, and the obtained pulp is heated to 70° C. and conveyed to a medium-concentration pulp pipe by a spiral conveyor after concentration of the pulp reaches 10-13%. The pulp is subject to thermal refining in a medium-concentration pulp pipe to eliminate air and to be fluidized and then conveyed to an oxygen delignification reaction tower by a centrifugal medium-concentration pulp pump. The pulp is mixed with added oxygen of 30 kg for it pulp and alkali solution with alkali content being 3% of the bone dry raw material based on sodium hydroxide in the pipe and heated by feeding steam to the pipe before being fed into the reaction tower. Then, the pulp is fully mixed in a mixer and then fed into the oxygen delignification reaction tower, magnesium sulfate is used as a protectant, magnesium sulfate added is 0.8% of the bone dry raw material, the inlet temperature is 98° C., the inlet pressure is 1.05 Mpa, the condition is kept 85 min to allow the pulp to receive sufficient delignification reaction, temperature is 102° C. and pressure is kept at 0.4 MPa at the top of the tower. The pulp is blown to a pulp chest and diluted to obtain the unbleached pulp after finishing treatment. The unbleached straw pulp has a breaking length of 6.0 km, folding number of 70, tear strength of 230 mN, whiteness of 40% ISO and beating degree of 35° SR.
[0174] Up to 80% of the unbleached straw pulp and 20% of unbleached wood pulp by weight are beaten at the beating concentration of 3.2% and 4.0% respectively in a double cylinder refiner and then in a double disc refiner, and quality standards for finished pulp obtained after beating are as follows: beating degree of 50° SR and wet weight of 1.8 g for the straw pulp and beating degree of 41° SR and wet weight of 1.5 g for the hardwood pulp. The unbleached wood pulp is that of the prior art, comprises unbleached sulfate softwood pulp, unbleached sulfite softwood pulp, etc. and has a breaking length of 4.5 km, tear strength of 500 mN, whiteness of 18% ISO, folding number of 1000 and beating degree of 38° SR.
[0175] The beaten pulp is mixed evenly and manufactured to obtain the unbleached towel paper. The manufacturing is performed in a single cylinder and inclined wire paper machine. The unbleached towel paper has an basis weight of 45.0 g/m 2 , transverse suction range of 55 mm/100 s, longitudinal wet tensile strength of 28 N/m and whiteness of 41% ISO.
Example 16
[0176] Rice straw is prepared by a dry method using a hammer crusher and then put into a spherical digester, cooking liquor is added to the spherical digester, alkali used is 15% of the bone dry raw material based on sodium hydroxide, liquor ratio is 1:3, anthraquinone added is 0.6% of the bone dry raw material, and the mixture is heated to 120° C. for the first time, insulated at the temperature for 20 min, then relieved for 20-30 min, heated to 168° C. for 40 min for the second time and insulated for 90 min. High-hardness pulp obtained after cooking has hardness of 18 equivalent to 27 Kappa number and beating degree of 17° SR and is conveyed to a conventional single spiral press master with variable diameter for extracting the black liquor for pressing, the pulp from the press master is diluted to 2.5% with diluted black liquor, then conveyed to a hop sieve for coarse pulp screening with hop sieve loss of 0.2% and delagged by a high-concentration slag separator with loss of 0.1%, the pulp obtained after deslagging is fed into a horizontal belt pulp washer for washing, pulp concentration is 3.0% while washing, the pulp from the pulp washer has concentration of 9%, temperature is kept at 68-70° C. during the washing process, and the pulp is conveyed to a deflaker for disintegration, heated to 70° C. and conveyed to a medium-concentration pulp pipe by a spiral conveyor after adjusting concentration. The pulp is subject to thermal refining in a medium-concentration pulp pipe to eliminate air and to be fluidized and then conveyed to an oxygen delignification reaction tower by a centrifugal medium-concentration pulp pump. The pulp is mixed with added oxygen of 20 kg for 1 t pulp and alkali solution with alkali content being 4% of the bone dry raw material based on sodium hydroxide in the pipe in the pipe and heated by feeding steam to the pipe before being fed into the reaction tower. Then, the pulp is fully mixed in a mixer and then fed into the oxygen delignification reaction tower, magnesium sulfate is used as a protectant, magnesium sulfate added is 1% of the bone dry raw material, the inlet temperature is 102° C., the inlet pressure is 1.12 Mpa, the condition is kept 70 min to allow the pulp to receive sufficient delignification reaction, temperature is 104° C. and pressure is kept at 0.5 MPa at the top of the tower.
[0177] The pulp is blown to a pulp chest and diluted to obtain the unbleached pulp after finishing treatment. The unbleached straw pulp has a breaking length of 4.4 km, folding number of 65, tear strength of 245 mN, whiteness of 37% ISO and beating degree of 34° SR.
[0178] Up to 95% of the unbleached straw pulp and 5% of unbleached wood pulp by weight are respectively beaten in a double disc refiner, the beating concentration of the straw pulp is 3.2% and that of the wood pulp is 4.5%, and quality standards for finished pulp obtained after beating are as follows: beating degree of 55° SR and wet weight of 2.0 g for the straw pulp and beating degree of 48° SR and wet weight of 2.0 g for the wood pulp. The unbleached wood pulp is unbleached sulfate hardwood pulp of the prior art.
[0179] The beaten pulp is mixed evenly and manufactured to obtain the unbleached toilet paper.
[0180] The unbleached towel paper has an basis weight of 18.0 g/m 2 , transverse suction range of 60 mm/100 s, tensile index of 7.0 N.m/g, softness of 130 mN and whiteness of 50% ISO.
Example 17
[0181] Giant reed is prepared by a conventional dry method and then put into a spherical digester, cooking liquor is added to the spherical digester, alkali used is 11% of the bone dry raw material based on sodium hydroxide, anthraquinone added is 0.8%, liquor ratio is 1:4, the mixture is heated to 130° C. for the first time, insulated at the temperature for 40 min, then relieved for 30 min, heated to 173° C. for 60 min for the second time and insulated for 60 min. High-hardness pulp obtained after cooking has hardness of 25 equivalent to 45 Kappa number and beating degree of 12° SR and is conveyed to a single spiral press master with variable diameter for extracting the black liquor in the prior art for pressing, the high-hardness pulp with concentration of 20% obtained after pressing is conveyed to a hop sieve for coarse pulp screening with hop sieve loss of 0.2% and delagged by a high-concentration slag separator with loss of 0.1%, the pulp obtained after deslagging is fed into a horizontal belt pulp washer for washing, pulp concentration is 2.0% while washing, the pulp from the pulp washer has concentration of 9%, temperature is kept at 68-70° C. during the washing process, and the pulp is heated to 70° C. and conveyed to a medium-concentration pulp pipe by a spiral conveyor after adjusting concentration. The pulp is subject to thermal refining in a medium-concentration pulp pipe to eliminate air and to be fluidized and then conveyed to an oxygen delignification reaction tower by a centrifugal medium-concentration pulp pump. The pulp is mixed with added oxygen of 20 kg for 1 t pulp and aqueous alkali with alkali content being 4% of the bone dry raw material based on sodium hydroxide in the pipe and heated by feeding steam to the pipe before being fed into the reaction tower. Then, the pulp is fully mixed in a mixer and then fed into the oxygen delignification reaction tower, magnesium sulfate is used as a protectant, magnesium sulfate added is 1% of the bone dry raw material, the inlet temperature is 102° C., the inlet pressure is 1.12 Mpa, the condition is kept 75 min to allow the pulp to receive sufficient delignification reaction, temperature is 104° C. and pressure is kept at 0.5 MPa at the top of the tower. The pulp is blown to a pulp chest and diluted to obtain the unbleached pulp after finishing treatment. The unbleached straw pulp has a breaking length of 5.0 km, folding number of 69, tear strength of 255 mN, whiteness of 42% ISO and beating degree of 33° SR.
[0182] Up to 70% of the unbleached straw pulp and 30% of unbleached wood pulp by weight are respectively beaten in a cylindrical refiner at beating concentration of 3.8%, beating pressure of 0.15-0.20 MPa and beating current of 65 A, and then beaten in a double disc refiner at beating concentration of 3.3%, beating pressure of 0.20 MPa and beating current of 60 A, and quality standards for the finished pulp after beating are as follows: beating degree of 48° SR and wet weight of 2.8 g. The unbleached wood pulp is that of the prior art, comprises unbleached sulfate softwood pulp, unbleached sulfite softwood pulp, etc. and has a breaking length of 6 km, tear strength of 1000 mN, whiteness of 18% ISO, folding number above 1000 and beating degree of 40° SR.
[0183] The beaten pulp is manufactured to obtain the unbleached toilet paper.
[0184] The unbleached toilet paper has an basis weight of 11.0 g/m 2 , transverse suction range of 80 mm/100 s, tensile index of 10.0 N.m/g, softness of 120 mN and whiteness of 38% ISO.
Example 18
[0185] Rice straw, wheat straw and reed are prepared by a dry method using a hammer crusher at a mass ratio of 1:3:1 and then filled in hot black liquor at 135° C. into a cooker by a filler at liquor ratio of 1:8, the cooker cover is closed after the cooker is full, cooking liquor at 145° C. is added to the cooker, alkali used is 11% of the bone dry raw material based on sodium hydroxide, anthraquinone added is 0.8% of the bone dry raw material, the black liquor and air in the filler is discharged, pressure is increased to 0.6 MPa, a cooking liquor circulating pump and a tubular heater of the cooker are started to heat the cooking liquor to 160° C., and heating and insulating last 180 min. The hot black liquor is exchanged by diluted black liquor and conveyed to a hot black liquor tank, high-hardness pulp obtained after cooking has hardness of 19 equivalent to 29 Kappa number and beating degree of 16° SR and is conveyed to a conventional single spiral press master with variable diameter for extracting the black liquor for pressing, the pulp from the press master is diluted to 3.0% with diluted black liquor, then conveyed to a hop sieve for coarse pulp screening with hop sieve loss of 0.2% and delagged by a high-concentration slag separator with loss of 0.1%, the pulp obtained after deslagging is fed into a horizontal belt pulp washer for washing, pulp concentration is 3.0% while washing, the pulp from the pulp washer has concentration of 9%, temperature is kept at 70° C. during the washing process, the pulp is conveyed to a deflaker for disintegration, and the pulp is subject to thermal refining in a medium-concentration pulp pipe to eliminate air and to be fluidized and then conveyed to an oxygen delignification reaction tower by a centrifugal medium-concentration pulp pump. The pulp is mixed with added oxygen of 20 kg for 1 t pulp and aqueous alkali with alkali content being 4% of the bone dry raw material based on sodium hydroxide in the pipe and heated by feeding steam to the pipe before being fed into the reaction tower. Then, the pulp is fully mixed in a mixer and then fed into the oxygen delignification reaction tower, magnesium sulfate is used as a protectant, magnesium sulfate added is 1% of the bone dry raw material, the inlet temperature is 95° C., the inlet pressure is 0.9 Mpa, the condition is kept 75 min to allow the pulp to receive sufficient delignification reaction, temperature is 100° C. and pressure is kept at 0.4 MPa at the top of the tower. The pulp is blown to a pulp chest and diluted to obtain the unbleached pulp after finishing treatment. The unbleached straw pulp has a breaking length of 6.5 km, folding number of 45, tear strength of 250 mN, whiteness of 42% ISO and beating degree of 33° SR.
[0186] Up to 95% of the unbleached straw pulp and 5% of unbleached wood pulp by weight are respectively beaten in a double disc refiner at the beating concentration of 3.4%, and quality standards for finished pulp obtained after beating are as follows: beating degree of 48° SR and wet weight of 2.9 g. The unbleached wood pulp is that of the prior art, comprises unbleached sulfate softwood pulp, unbleached sulfite softwood pulp, etc. and has a breaking length of 6 km, tear strength of 1000 mN, whiteness of 20% ISO, folding number above 1000 and beating degree of 38° SR.
[0187] The beaten pulp is manufactured to obtain the unbleached toilet paper.
[0188] The unbleached towel paper has an basis weight of 13.0 g/m 2 , transverse suction range of 30 mm/100 s, longitudinal wet tensile strength of 22 N/m, softness of 140 mN and whiteness of 50% ISO.
Example 19
[0189] Wheat straw is prepared by a hammer crusher and then put into a spherical digester, cooking liquor is added to the spherical digester, ammonium sulfite added is 9% of the bone dry raw material, liquor ratio is 1:3, the wheat straw material is heated to 110° C. for the first time, insulated at the temperature for 30 min, then relieved for 25 min, heated to 168° C. for 60 min for the second time and insulated for 90 min. The high-hardness pulp obtained after cooking has hardness of 22 equivalent to 35.5 Kappa number and beating degree of 11.6° SR and is diluted to 2.5% with diluted black liquor and then screened by a screening method in the prior art, for example, hop screening method with loss of 0.5%. The high-hardness pulp is washed by a vacuum pulp washer in the prior art. The high-hardness pulp with concentration of 10% obtained after washing is conveyed to a medium-concentration pulp pipe. The high-hardness pulp is conveyed to an oxygen delignification reaction tower via a medium-concentration pulp pump. The pulp is mixed with added oxygen of 20 kg for 1 t pulp and aqueous alkali with alkali content being 4% of the bone dry raw material based on sodium hydroxide in the pipe and heated by feeding steam to the pipe before being fed into the reaction tower. Then, the pulp is fully mixed in a mixer and then fed into the oxygen delignification reaction tower, magnesium sulfate is used as a protectant, magnesium sulfate added is 1% of the bone dry raw material, the inlet temperature is 95° C., the inlet pressure is 0.9 Mpa, the condition is kept 75 min to allow the pulp to receive sufficient delignification reaction, temperature is 100° C. and pressure is kept at 0.3 MPa at the top of the tower. The pulp is blown to a pulp chest and diluted to obtain the unbleached pulp after finishing treatment. The unbleached straw pulp has a breaking length of 5.0 km, folding number of 40, tear strength of 220 mN, whiteness of 40% ISO and beating degree of 34° SR. The unbleached straw pulp is beaten, and quality standards for the finished pulp obtained after beating are as follows: beating degree of 45° SR and wet weight of 2.8 g.
[0190] The beaten pulp is manufactured to obtain the unbleached wiping paper. The manufacturing is performed in a single cylinder and long wire paper machine
[0191] The unbleached wiping paper has an basis weight of 14.0 g/m 2 , transverse suction range of 100 mm/100 s, longitudinal wet tensile strength of 55 N/m and whiteness of 45% ISO.
Example 20
[0192] Wheat straw is prepared by a dry method using a hammer crusher and then put into a spherical batch cooker, cooking liquor is added to the spherical batch cooker, ammonium sulfite added is 13% of the bone dry raw material, liquor ratio is 1:4, the mixture is heated to 120° C. for the first time, insulated at the temperature for 40 min, then relieved for 25 min, heated to 168° C. for 60 min for the second time and insulated for 90 min. The high-hardness pulp obtained after cooking has hardness of 16 equivalent to 23 Kappa number and beating degree of 23.4° SR and is diluted to 2.5% with diluted black liquor and then screened by a screening method in the prior art, for example, hop screening method with loss of 0.2%. The high-hardness pulp is washed by a vacuum pulp washer in the prior art. The high-hardness pulp with concentration of 10% obtained after washing is heated to 70° C. and conveyed to a medium-concentration pulp pipe by a spiral conveyer.
[0193] The pulp is subject to thermal refining in a medium-concentration pulp pipe to eliminate air and to be fluidized and then conveyed to an oxygen delignification reaction tower by a centrifugal medium-concentration pulp pump. The pulp is mixed with added oxygen of 20 kg for 1 t pulp and aqueous alkali with alkali content being 3.5% of the bone dry raw material based on sodium hydroxide in the pipe and heated by feeding steam to the pipe before being fed into the reaction tower. Then, the pulp is fully mixed in a mixer and then fed into the oxygen delignification reaction tower, magnesium sulfate is used as a protectant, magnesium sulfate added is 1% of the bone dry raw material, the inlet temperature is 95° C., the inlet pressure is 0.9 Mpa, the condition is kept 75 min to allow the pulp to receive sufficient delignification reaction, temperature is 100° C. and pressure is kept at 0.4 MPa at the top of the tower. The pulp is blown to a pulp chest and diluted to obtain the unbleached pulp after finishing treatment. The unbleached pulp has a breaking length of 6.81 cm, folding number of 50, tear strength of 250 mN, whiteness of 45% ISO and beating degree of 36° SR.
[0194] Up to 70% of the unbleached straw pulp and 30% of unbleached wood pulp by weight are beaten in a double disc refiner at the beating concentration of 3.0% and 4.5% respectively, and quality standards for finished pulp obtained after beating are as follows: beating degree of 50° SR and wet weight of 1.8 g for the straw pulp and beating degree of 46° SR and wet weight of 1.2 g for the wood pulp. The unbleached hardwood pulp has a breaking length of 6.5 km, tear strength of 1000 mN, whiteness of 18% ISO, folding number of 1000 and beating degree of 38° SR.
[0195] The beaten pulp is mixed evenly and manufactured to obtain the unbleached wiping paper. The manufacturing is performed in a double cylinder and long wire paper machine. The unbleached wiping paper has an basis weight of 36.0 g/m 2 , transverse suction range of 60 mm/100 s, longitudinal wet tensile strength of 40 N/m and whiteness of 45% ISO. | Provided is an unbleached paper product made from grass type pulp, the unbleached paper product has a brightness of 35-60% ISO, the grass type pulp is unbleached. The unbleached paper product includes an unbleached toilet paper, an unbleached hand towel, an unbleached wiping paper, an unbleached duplicating paper, an unbleached meal container, an unbleached food wrapping paper and an unbleached printing paper. The paper products have a high intensity and have no detection of dioxin and absorbable organic halides in the harmful substance detection test. | 3 |
RELATED APPLICATIONS
[0001] This Application claims rights under 35 USC §119(e) from U.S. application Ser. No. 61/154,638 filed Feb. 23, 2009, the contents of which are incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to a computerized evaluation system for program or system performance and more particularly to methods for integrating various capabilities in a web-based performance management and optimization suite.
BACKGROUND OF THE INVENTION
[0003] Many companies are involved in processes which are in need of evaluation and redesign in order to effectuate better performance and savings. While in the past methodologies have existed for providing robust business cases and business plans, when a manager is faced with an underperforming process or system, the prior approach to obtaining better yields or acceptability has been to assess mission performance but usually in a haphazard and disconnected manner. The result is that improvements in various sub-processes do not necessarily result in overall better performance or savings due to unintended consequences and information that while available, has not been brought to the fore in making management decisions.
[0004] Thus, mission performance is to be improved that results in a lower total ownership cost and a methodology is clearly required to take into account all of the factors in a complete process in order to develop a systematic approach in order to assure complete flow of information and to be able to design a solution that guarantees that system needs are met. What is in short required is a total data capture and a complete cause and effect analysis so that one can take existing infrastructure and processes and implement changes to the infrastructure or processes to assure a beneficial result that can increase performance and reduce overall operating costs.
[0005] One of the processes for which improvement is desired is a fleet management process which is addressed in one application by U.S. patent application Ser. No. ______ (docket number BAEP-1159), entitled Telenostics, filed on even date, assigned to the assignee hereof and incorporated herein by reference. Here a method known as Telenostics develops realtime data regarding remote and mobile assets, and formulates maintenance plans and procedures used to improve fleet operations. The Telenostics operation while providing fleet managers with realtime data and information permits the fleet mangers to provide additional or refined maintenance tasks. However the Telenostics system with its diagnostic and prognostic algorithms is nonetheless in need of a methodology that assures taking into account all of the information available and providing specific suggestions for improvement of the process based on a rigorous and complete analysis of the process itself.
[0006] By way of further background, the telenostics method addresses remote and mobile assets as well as fleet operations. This method enhances mission performance at a lower total ownership cost. The operational principles guide movement to the point of performance those actions that achieve mission performance with a minimum of infrastructure. It is not just about getting a current snapshot of operations.
[0007] Note, Telenostic systems are described in the following U.S. patent applications, filed on even date herewith, assigned to the assignee hereof and incorporated herein by reference: Ser. No. ______ (docket number BAEP 1140) Diagnostic Connector Assembly (DCA) Interface Unit (DIU), Ser. No. ______ (docket number BAEP 1141) In Service Support Center and Method of Operation, Ser. No. ______ (docket number BAEP 1159) Telenostics, Ser. No. ______ (docket number BAEP 1160) Portable Performance Support Device and Method for Use, and Ser. No. ______ (docket number BAEP 1161) Telenostics Performance Logic.
[0008] A need, however, still exists to improve the telenostics method.
SUMMARY OF INVENTION
[0009] What is provided by the subject system is a computer-assisted evaluation and recommendation system based on templates that are used to prompt individuals to answer questions that assure completeness of the evaluation as well as completeness of the suggested response and the assurance of follow-ups. The methodology involves templates which by prompting force capture of information, the evaluation of this information, compilation of a redesign tasks, generation of targeting task, task implementation and a follow-up proceeding which is turn followed by justifications for the proposed changes to a process.
[0010] By applying the computerized methodology and templates, one arrives at performance-based solutions for optimizing performance in which business intelligence can be improved by providing timely information, adapted to provide only the relevant knowledge that most affects performance outcomes and then takes advantage of multitudes of databases and information to assure completeness and effectiveness of the evaluation and recommendation process.
[0011] The subject system takes a business model for an industry and takes advantage of the factors, metrics and knowledge which most influences the desirable performance of the system to be evaluated. The result is a targeted solution tailored towards newer modified performance needs.
[0012] In one embodiment, subject methodology involves a capture phase intended to document the concurrent or as-is processes involved because it is important to understand the starting condition in order to assess the potential benefits of a redesign effort and compare “before and after” performance. Being able to document the as-is condition also results in the development of a transition strategy and ability to assess the resources associated with the transition activity required in a redesign. Thus, the capture phase establishes the foundation for an evaluation phase to identify targets of opportunity that warrant special attention in a redesign effort.
[0013] In the evaluation stage the objective of the evaluation activity is to reach a common understanding of the problems involved and the process to be evaluated. The evaluation results in identifying key performance drivers that must be addressed in any redesign effort.
[0014] It is noted that redesign involves sewing the seeds of imagination, meaning a creative approach to establishing a new process.
[0015] There are many appropriate principals to guide the redesign effort and in particular, in one embodiment the subject approach to redesign is a two-step approach.
[0016] The first step is to prompt creative re-think process steps to eliminate and reduce identified issues.
[0017] The second step is to apply realtime methodologies to achieve the desired end results.
[0018] In summary, what is provided is a computer-aided prompting system involving the use of templates for forcing the evaluation into a c-capture, e-evaluation, r-redesign, t-target, i-implementation and an f-follow up process, so that upon using the templates, complete analysis of an entire process is assured. Targeted redesign implementation which is the result of the evaluation thus entails in-depth and complete solutions to identified system problems.
[0019] According to one embodiment of the present invention, users are provided with performance based solutions for optimizing the performance metrics that are most important to their industry desires. Business intelligence can be improved by accessing information that is timely, adapted to provide only the relevant knowledge that most affects performance outcomes, and can take advantage of multitudes of databases and information that can be brought to bear without the internal investment requiring IT or development personnel. As the business model changes, and the factors/metrics/knowledge which most influence desirable performance objectives change, the result is that the performance logic model can change as well as the required level of information needs. This reduces or increases subscription costs, but ultimately increases revenue by the operating/total life cycle savings, with the ability to target a solution tailored toward new or modified performance needs.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] These and other features of the subject invention will be better understood in connection with the Detailed Description, in conjunction with the Drawings, of which:
[0021] FIG. 1 is a diagrammatic illustration of the subject prompting system in which prompts relating to capture, evaluation, redesign, target, implementation, follow-up and yield are generated by a processor driving a display or printer in which templates are utilized to prompt an individual to enter data which assist in the evaluation of a particular system and result in a suggested course of action;
[0022] FIG. 2 is a chart illustrating the types of templates utilized in the capture, evaluation, redesign, targeting, implementation and follow-up portions of the subject CERTIFY system;
[0023] FIG. 3 is a capture worksheet checklist template for use in the subject prompting system;
[0024] FIG. 4 is a an evaluation worksheet checklist template for use in the subject system;
[0025] FIG. 5 is a redesign worksheet checklist template for use in the subject system;
[0026] FIG. 6 is a target worksheet checklist template for use in the subject system;
[0027] FIG. 7 is a diagrammatic illustration of an implementation checklist template for use in the subject system;
[0028] FIG. 8 is a diagrammatic illustration of a follow-up worksheet checklist template for use in the subject system; and,
[0029] FIG. 9-56 are templates presented by the subject system which may be provided in the form of dialog boxes for the entry of information by a user in order to satisfy the requirements of the subject CERTIFY system.
DETAILED DESCRIPTION
[0030] The subject CERTIFY system is a computer-assisted system to be able to prompt individuals to take into account all of the processes of a particular system to evaluate the processes, to redesign the processes, to provide targeted assessment of the results of the capture, evaluate and redesign stages, to prompt the steps for the implementation of the targeted redesign and to prompt follow-up processes, whereby the CERTIFY system assures completeness and provides a targeted redesign for any system under analysis.
[0031] By way of example only, a telenostics system is discussed in terms of the specific prompting templates; it being understood that other systems other than a telenostics system primarily used for fleet management may take advantage of the CERTIFY system, thus to be able to provide better system performance, whatever the system is, and to provide concomitant cost savings.
[0032] The letters of the CERTIFY system correspond to prompts in particular areas which when a template is then filled out, the result is an exceedingly complete approach to solving problems in existing systems.
[0033] Referring now to FIG. 1 , the CERTIFY system uploads templates to a processor 10 , in which the templates relate to C-capture 12 , E-evaluation 14 , R-redesign 16 , T-target 18 , I-implement 20 , F-follow up 22 , and the Y-yield or justification 24 .
[0034] These templates are loaded into processor 10 and are filled out by a user 26 , in one embodiment through a keyboard 28 to a template completion module 30 and then to processor 12 .
[0035] The templates are displayed on a display or printer 32 , with the filled out templates resulting in a complete evaluation and a thoroughly considered suggested course of action in order to improve a particular system, here shown at 34 .
[0036] Referring now to FIG. 2 , the templates utilized in the CERTIFY system include as shown the capture templates, the evaluate templates, the redesign templates, the target templates, the implementation templates and the follow-up templates as well as a template to prompt a determination of the yield of the newly designed system or the results.
[0037] As mentioned above, the “capture” prompts are intended to document the current or “as-is” processes. The subject system assists in the assessing of the potential benefits of a redesign effort, the ability to compare before and after performance, the ability to develop a strategy which will result in a transition between the before and after performance, while at the same time assessing the resources associated with the transition activity. The capture prompts are used to establish the foundation for the evaluation phase to identify targets of opportunity that warrants special attention in a redesign effort.
[0038] As to the “evaluation” prompts as mentioned before, the objective of the evaluation is to reach an understanding of the particular problems involved in the system as well as to be able to embark on a redesign effort.
[0039] As mentioned above the “redesign” effort centers around templates that result in the prompting of creative thinking to eliminate or reduce identified issues and to apply various technologies to enable the desired end results.
[0040] The “targeting” prompts have a goal to jointly assess the results of the capture, evaluate and redesign stages and to permit individuals to agree on the next steps to be taken. Once there is agreement, the targeted project is articulated. Also needed, in terms of joint concurrence before proceeding, is a project delivery approach. There are business models including CAPEX (capital expense), OPEX (operating expense) and P4P (pay for performance) that focus the project delivery approach. The final step of the targeting prompts is to prompt individuals to detail the aspects of the anticipated project into a concise proposal that conveys the essence of the agreed upon target.
[0041] In the “implementation” prompts one must take very seriously the management of the implementation phase of any project. In order to do so, one is prompted to look at the detail, design and development required, the system delivery required, and the project management control of the undertaking.
[0042] Project management control covers a communications plan, a work breakdown structure, roles and responsibilities, a resource plan, a procurement plan, a quality plan, a project schedule, a project budget, a change management plan and an implementation checklist.
[0043] It is noted that meticulous project planning is instrumental to the success of the CERTIFY effort. Of particular importance is system delivery. System installation and delivery is more than simply installing the enabling technology. It also involves a careful migration strategy to minimize disruption to operations. It involves hardware and software installation and verification of the planned functionality, including final system level testing. It also includes delivery of system documentation, completing the customer training, establishing feedback systems and maintenance procedures. Note, it is imperative to prompt individuals to document a basis for process improvement and current assessment, so that the process improvement and assessment are institutionalized at this time.
[0044] Follow-up prompts are also extremely important. The commitment to improving a system does not stop with project installation. At defined intervals, individuals are prompted to meet and assess the results, the successes, the challenges and the plans for the future. Sustainment and maintenance are quite often the biggest point of failure for a project. Follow-up prompts are intended to not only sustain but to institutionalize a continuous improvement system that takes advantage of all the capabilities of a high performance organization.
[0045] Finally, the yield of the entire process is to be ascertained in terms of documenting the results, both in terms of measurable improvements and in terms of cost savings.
[0046] As will be described in the following Figures involving templates, the capture prompts include process description, a stakeholder summary, the asset environment, process map diagrams, organizational structures, constraint summaries, decision capture charts, a so-called COCO listing, meaning a listing of the chain of custody operations, current metrics, data capture mechanisms, IT structure, information flow, wireless structure, PST or performance support technologies, process personnel, competitor understanding, opportunity listings and interview documentation. By having prompts to generate these inputs, the capture portion of the CERTIFY system is completely achieved.
[0047] With respect to the evaluation prompts, values stream and waste analysis prompts are called for, as well as metric analysis, issue and error analysis, financial impact in the form of a worksheet, benchmarking, and PopTech Gap analysis where PopTech Gap refers to the point of performance technical assessment for technology gaps. Also, TOOL or target of opportunity listings are important in the evaluation portion, in which the TOOL summary incorporates the targets of opportunity listings.
[0048] With respect to the redesign prompts, there is a design principal analysis prompt, a POPTECH assessment prompt, an analytics prompt, a realtime data plan prompt, a redesign storyboard prompt, a preliminary cost and benefit prompt, a decision and action summary prompt, and a KPM analysis prompt, in which KPM refers to key performance metrics. Moreover, there is a risk summary prompt and a technology evaluation prompt.
[0049] With respect to the target prompts, a redesign prompt includes prompting for storyboarding and summaries, and a target prompt includes prompts for performance, metrics, and business return. The target prompts also include business relationships, capital expense or CAPEX analysis, an OPEX or operating expense analysis and/or a prompt for a P4P or pay for performance analysis. Also in the target prompts are scope prompts, phasing prompts and schedule prompts, as well as executive summary prompts and proposal and contract prompts.
[0050] With respect to the implement prompts, there are prompts for a work approach including design, point of performance, on, at and off prompts, a collection prompt, a point of performance prompt, and architecture prompts including communications prompts and backend prompts. Moreover in the implement prompt section there are development prompts, integrate prompts, deploy prompts and project management prompts, as well as project integration prompts, project scope prompts, project time prompts, project cost prompts, project quality prompts, project human resources prompts, project communications prompts, project risk prompts and project performance prompts.
[0051] Finally, with respect to follow-up prompts, there are performance prompts involving metric prompts and validation and benefits audit performance prompts, along with prompts for system maintenance, including prompts for corrective adaptive and perfective maintenance strategies, a technology sustainment prompt, a lessons learned prompt and a prompt to engage in a Kaizen plan which is a Japanese quality management program and technique.
[0052] Referring to FIG. 3 , the capture worksheet checklist prompts are as listed and is also summarized in FIG. 2 .
[0053] Referring to FIG. 4 , as to the evaluate worksheet checklist prompts, these prompts are also as listed in FIG. 2 .
[0054] Referring to FIG. 5 the redesign worksheet checklist prompts are as described in FIG. 2 . Referring to FIG. 6 the target worksheet checklist prompts are also described in connection with FIG. 2 .
[0055] Referring to FIG. 7 , the implement worksheet checklist prompts are as described in FIG. 2 and finally in FIG. 8 the follow-up worksheet checklist prompts are also described in FIG. 2 .
[0056] It will be appreciated that the prompts are provided by templates which prompt an individual to fill in the data required in the templates by thinking about what the individual is prompted to consider.
[0057] Referring to FIGS. 9-56 , what is described are the templates used in a telenostics system, which are applicable across the board to many different types of businesses. These templates detail prompts that are required for completeness of a capture of a system, its evaluation, its redesign and targeted tasks that result in an implementation for improving the system as a whole.
[0058] What will be seen is that the completeness and thoroughness of the evaluation of any system requires the CERTIFY components at least in some detail for any system to be evaluated. The general prompts of capture, evaluate, redesign, target, implement, follow-up and yield are the core prompts required for the above purposes.
[0059] More particularly and especially for a fleet management system, in practicing the present invention a vehicle site fleet is visited and a business target is defined. The following steps are then carried out.
[0060] The “capture” phase is intended to document the current or “as-is” processes. Even though the redesign will most likely be a dramatic departure from the “as-is” procedure, it is important to understand the starting condition in order to: assess the potential benefits of the redesign effort; compare the “before” and “after” performance; develop the transition strategy, and assess the resources associated with the transition activity; establish the foundation for the “evaluation” phase to identify targets of opportunity that warrant special attention in the redesign effort; and to utilize flowcharting, flow measurement, and a structural analysis to aid in establishing the “as-is” picture.
[0061] The objective of the evaluation activity is to reach a common understanding of present problems. There are many diverse approaches for evaluating the captured information. Industrial engineering and operations research approaches are examples of classic approaches. They may not lead to radical process improvements. However, they are extremely useful in identifying the key performance drivers that must be addressed in the redesign effort. Cycle time reduction is a good example using measurements such as response ratios to evaluate time-based competition. A response ratio measures the elapsed time it takes to complete a customer transaction divided by the actual time spent performing the transaction. For instance, if the elapsed time for processing a credit application is 4 hours, and the actual time spent processing the application is 12 minutes, the response ratio is 20. Obviously, high response ratios indicate potential targets of opportunity for redesign. Evaluation does not stop at the metric analysis stage. “Walking the workflow” and benchmarking can also provide valuable process insight.
[0062] There are no real cookbook recipes for the actual redesign activity. Redesign involves “sowing the seeds of imagination” through system prompts to establish a creative approach to establishing a new process. It means challenging the old assumptions and the old way of doing business. It also means departing from the comforts and security of the status quo. Not everyone is well suited for this kind of activity. Many feel threatened by change rather than energized by the opportunity. Although there is no simple algorithm for stepping through a redesign effort, there are many appropriate principles established through system prompts from the templates to help guide the effort. In one embodiment the redesign is a two step approach:
[0063] The first step is to prompt a creative rethink process steps to eliminate/reduce identified issues. The second step is to apply real-time telenostics method to enable the desired end results of the stakeholders.
[0064] Those skilled in the art will appreciate that by means of the present invention, fleet management will be provided with performance based solutions for optimizing the performance metrics that are most important to their fleet/industry/financial desires. Business intelligence can be improved by affording them information that is timely, adapted to provide only the relevant knowledge that most effects performance outcomes for them, and can take advantage of multitudes of databases and information that can be “brokered” to them without the internal investment by their own IT or development organizations. As their business model, industry, or fleet changes, and the factors/metrics/knowledge which most influence their desirable performance objectives change, they can request that their performance logic model changes and/or their required level of information needs, reducing or increasing their subscription costs, but ultimately increasing their revenue by the operating/total life cycle savings with the ability to target a solution tailored toward their new or modified performance needs.
[0065] While the present invention has been described in connection with the preferred embodiments of the various figures, it is to be understood that other similar embodiments may be used or modifications or additions may be made to the described embodiment for performing the same function of the present invention without deviating therefrom. Therefore, the present invention should not be limited to any single embodiment, but rather construed in breadth and scope in accordance with the recitation of the appended claims. | A method for managing a commercial process comprising the steps of capturing and understanding current as-is processes; comparing before and after performance; developing a transition strategy; evaluating performance using flow charts; redesigning using creative thinking; obtaining real-time data about the process; performing predictive performance actions based on remaining useful life; and performing aggregation, analysis and information fusion to enable process and users to optimize the commercial process. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. application Ser. No. 10/667,817, filed Sep. 22, 2003, the disclosure of which is hereby incorporated by reference herein in its entirety and all commonly owned.
FIELD OF THE INVENTION
[0002] The subject invention pertains to an apparatus for automatically opening a door and for more specifically for the hands-free opening of a restroom door.
BACKGROUND OF THE INVENTION
[0003] Bathroom door handles can be a hot bed for germs due to the poor hygiene practices of others. In an effort to avoid contact with the door handle, restroom patrons will often utilize any means available to open a restroom door and exist common necessary to avoid contact with the door handle. Quite often people use their feet to pry the door open, a paper towel to insulate their hands from the door handle, grasp the door in a location other than the handle, or even wait for another patron to enter, in an effort to avoid contact with the door altogether.
[0004] Automatic door openers are well-known in the art. They are generally operated by motion detectors and have bidirectional motors that both open and close the doors as a patron approaches the door. Essentially, the patron enters a zone in which a proximity detector detects the presence of the patron and automatically opens the door. There are certain drawbacks of these automatic door openers especially in the close quarters of a public restroom. For example, due to the small size of many public restrooms, proximity detectors can activate from almost any movement in the restroom. This results in the constant opening and closing of the restroom door due to the movement of the patron inside the restroom. In addition, patrons entering the restroom from the outside will often trigger the door to swing inward where another patron may be standing.
[0005] Attempts to remedy these drawbacks have been made by way of motors or opening mechanisms which stop progress when obstructed. While these improvements resolve a portion of the problems in that the patron in the path of the door is not injured, it is still inconvenient for all involved. Keeping convenience in mind, it is desirable to have a restroom door that can be opened both manually or automatically upon the affirmative action of a patron on the inside of the restroom. This allows the patron on the inside of the restroom to have a choice of automatically or manually opening the restroom door, as well as making the patron aware of the doors automatic opening so that any impedance thereof may be avoided.
SUMMARY OF THE INVENTION
[0006] Accordingly, it is an object to the present invention to provide an automatic restroom door opener initiated upon the affirmative action or command of a restroom patron. The automatic door opener comprises an actuator; a control unit and a power assisted drive mechanism. The drive mechanism comprises a limit unit which is in communication with a conventional door closer which allows the door to be opened manually from the inside or outside or automatically from the inside upon the affirmative action of a restroom patron. The affirmative action of the restroom patron required to open the automatic door, for example, can comprise a hand waving or oral command wherein the patron is provided instruction through iconic symbols triggered by the proximity of the patron to the actuator.
[0007] The actuator can be mounted in any area near the restroom door. For example, between the sink and door at a height sufficient to accommodate nearly any restroom patron. The actuator comprises at least one proximity sensor for detecting the proximity of a patron within at least one specific proximity zone. Each proximity zone corresponds to a specific distance from the activator.
[0008] For example, the proximity detector detects the presence of a patron in a first zone. The actuator then provides an iconic instruction and/or an audible signal to instruct the patron to wave hi or her hand close to the actuator. When the patron's hand is waved in front of the actuator, it enters a second proximity zone. The proximity sensor, or a second proximity sensor, then detects the proximity of the patron's hand to the actuator, provides an audible signal of detection and begins the door-opening process. At any time the door may be opened manually from inside or out.
[0009] The actuator alerts to the patron in each of the various zones and provides a corresponding iconic symbol on the face of the interface will light thereby instructing the patron on the process for opening the door. For example, as patron approaches the restroom door to exit the restroom, the proximity detector detects the presence of the patron as the patron enters a first proximity zone. Detecting the presence of the patron I the actuator flashes a first signal which alerts the patron I to the presence of the actuator and provides a “wave hand” iconic symbol instructing the patron I to wave his or her hand in front of the actuator. As the patron approaches the actuator and waves his or her hand in front of it, the patron's hand enters a second proximity zone and the actuator can illuminate a second iconic symbol or color which alerts the patron to the automatic opening of the door.
[0010] For example, the first and second proximity zones can be variably set to meet the needs of the specific restroom installation. The affirmative action for example can be a movement such as a hand wave or oral command in front of the actuator which then initiates the opening of the door. Upon completion of the affirmative action of the patron, a second audible signal can be provided alerting the patron to the opening of the door. This informs the patron that the inward swinging door will be opening immediately.
[0011] When initiated, the control unit sends a signal to the power-assisted drive mechanism attached to a conventional door closer. The conventional door closer can be a preexisting door closer or a door closing apparatus integrated into the system. Conventional door closers generally comprise an external gear on the top and bottom of the closer that rotates with the opening and closing of the door to which it is attached. When the external gear of the door closer is rotated in the appropriate direction, the door closer can be reversed and can operate to open the door.
[0012] The power-assisted drive mechanism comprises a motor, a gear box and a limit unit. The motor may be an AC or a DC motor, unidirectional or bi-directional. The gear box may comprise a variety of gears to translate the torque of the motor to the limiting unit which is attached to an external gear on the door closer. For example, the gear box may comprise a series of reduction gears in further communication with the limit unit. The limit unit provides for the positive opening of the door by the power-assisted drive mechanism. While there is a variety of methods in which to accomplish this task, the preferred method disclosed herein allows for power-assisted door opening as well as unobstructed manual door opening.
[0013] As the apparatus opens a swinging door, the control unit senses the maximum angle θ and adjusts the motor function accordingly. For example, when the door opens to the maximum angle θ, the control unit can eliminate all power to the motor thereby allowing the limit unit to reset the motor as the door comes to a closed position or in the alternative the control unit can reset the motor under power. In addition to detecting the maximum angle of the door θ, the control unit can also detect any fluctuation in current (i.e., voltage) caused by an impedance in the opening door and thereby initiate a failsafe program that operates to stop the opening of the door. Accordingly, should somebody step in the way of the door as it is opening as the door comes in contact with an obstruction such as a person, the control unit will detect an increase in motor power and initiate the failsafe program.
[0014] When the opening process is completed, the power to the motor can be eliminated or reversed by the control unit and the normal function of the door closer can take over and close the door in its usual fashion. Such a feature is highly desirable for a number of reasons. First, such a system allows for the bathroom door to open both automatically and manually. Second, the apparatus is easily adaptable to existing conventional door closers. Third, by utilizing an existing door closer time and money are saved by way of installation costs and materials. Further objects and advantages of the present invention will become apparent by reference to the following detailed description of the preferred embodiment and appended drawings wherein like reference numbers refer to the same feature, component, or element.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] For a fuller understanding of the invention, reference is made to the following detailed description, taken in connection with the accompanying drawings illustrating various embodiments of the present invention, in which:
[0016] FIG. 1 is a perspective view of an inward swing door comprising the apparatus according to the present invention.
[0017] FIG. 2 is a plan view of the actuator device according to the present invention.
[0018] FIG. 3 is a perspective view of the power-assisted drive mechanism according to the present invention.
[0019] FIG. 4 is a plan view of the power-assisted drive mechanism according to the present invention.
[0020] FIG. 5 is an alternative embodiment of the power-assisted drive mechanism according to the present invention.
[0021] FIG. 6 is an alternative embodiment of the power-assisted drive mechanism according to the present invention.
[0022] FIG. 7 is an illustration of the proximity zones according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0023] The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which preferred embodiments in the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be complete, and will fully convey and disclose the invention to those skilled on the art. Like numbers refer to like elements throughout, and the prime notation indicates similar elements in the alternate embodiments.
[0024] Referring now to FIG. 1 , an apparatus according to the present invention is illustrated and generally designated by the reference numeral 10 .
[0025] The door opening apparatus 10 illustratively includes an actuator 20 a control unit 22 and a power-assisted drive mechanism 24 . The power-assisted drive mechanism 24 illustratively is attached to a conventional door closer 26 . The conventional door closer 26 may comprise a preexisting door closer or a door closer integrated into the apparatus 10 . The apparatus provides for the egress from a restroom without requiring the manual contact with the door 28 .
[0026] The actuator 20 comprises a proximity sensor 40 , audible signals (not shown), a plurality of visual signals corresponding to the working status of the actuator. The control unit 22 is in electronic communication with the actuator 20 and the power-assisted drive mechanism 26 and functions to control both the actuator 20 and the power-assisted drive mechanism 24 . The power-assisted drive mechanism comprises a motor 60 a gear box 62 and a limit unit 64 . The door closer 26 may comprise an existing door closer or a door closer integrated with the apparatus 10 .
[0027] It will be appreciated by those skilled in the art that the control unit 22 communicates to the actuator 20 and the power-assisted drive mechanism 24 through wires, fiber optics, electro magnetic signals, or a combination thereof. It will also be appreciated by those skilled in the art that the electro magnetic signals can include infra-red, RF, or any other electro magnetic signal known in the art.
[0028] The actuator 20 comprises at least one proximity sensor 40 and a plurality of visual signals. The plurality of visual signals may comprise an attention signal 42 , an affirmative action signal 44 and a door opening signal 46 . By way of example, as a patron I approaches an inward swinging restroom door 28 to exit the restroom, the patron I enters a first proximity zone 80 and the proximity sensor 40 , in the actuator 20 , detects the presence of the patron I. The proximity sensor 40 sends an electronic signal to the control unit 22 which sends an electronic signal from the control unit 22 to the actuator 20 that instructs the actuator 20 to provide an alert signal to the patron I.
[0029] For example, the alert signal to the patron I may comprise an attention signal 42 , an audio signal (not shown) or a combination thereof. The attention signal 42 may comprise an illuminated iconic signal 42 which illuminates steadily or flashes to alert the patron I to the existence of the actuator 20 . The attention signal 42 may further comprise an audible signal.
[0030] As the patron I moves closer to the restroom door 28 the proximity sensor 40 detects that the patron I is within a certain zone (for example a distance from the actuator up to 18 inches) and sends an electronic signal to the control unit 22 which in turns sends an electronic signal back to the actuator 20 to indicate a change in operation status, for example flashing the affirmative action icon 44 on the actuator 20 . By way of example, the affirmative action visual signal 44 can instruct the patron I to wave their hand in front of the actuator 20 to initiate the opening of the door 28 .
[0031] In an alternative embodiment, the actuator 20 constantly flashes to get the attention of the patron I. In such an embodiment, a single proximity zone 82 can be used. The actuator 20 does not require a first proximity zone 80 to detect the presence of the patron I. Instead the actuator 20 flashes continuously in an “always on” mode. When the patron I desires to exit the restroom, the iconic instruction 44 is already illuminated and the patron I need only to take the affirmative action necessary to initiate the hands free door opener 10 .
[0032] As the patron I complies with the iconic instruction requiring the affirmative action, the proximity sensor 40 interprets the affirmative action and sends an electronic signal to the control unit 22 which, first, sends a signal back to the actuator to illuminate the door opening signal 46 and, second, initiates the door opening sequence.
[0033] To initiate the door opening sequence, the control unit 22 sends a signal to the power-assisted drive mechanism 24 . The power-assisted drive mechanism 24 comprises a motor 60 , gear box 62 , and a limit unit 64 . As will be appreciated by those skilled in the art, the motor 60 may be unidirectional or bi-directional AC or DC. The gear box 62 may comprise a variety of gears which operate to translate torque from the motor 60 to the limit unit 64 . By way of example, the preferred gears of the present invention comprise a series of reduction gears (not shown) that allow the torque of the motor 60 to be translated substantially perpendicular to the plane of the motor 60 , thus allowing a more compact power-assisted drive mechanism 24 . The limit unit 64 receives torque from the gear box 62 and functions to open the restroom door 28 to a fixed angle θ. It will be appreciated by those skilled in the art that the limit unit 64 may operate to allow the door 28 to be opened mechanically or manually.
[0034] As the motor 60 receives the signal from the control unit 22 under normal conditions, it will provide torque to the gear box 62 which then provides torque to the limit unit 64 which is in further communication with a door closer 26 .
[0035] The door closer 26 comprises an conventional door closing mechanism as is known in the art. For example, the door closer is mounted to the top of the door 28 and further comprises a double arm arrangement 68 that is attached to the header 70 above the door. Such a double arm arrangement 68 can operate to either push or pull the door 28 open depending on the configuration of the door closer 26 .
[0036] Conventional door closers generally comprise an external gear 66 on the top and/or bottom of the closer 26 that rotates with the opening and closing of the door 28 to which it is attached. The external gear 26 is generally connected to an internal piston (Not shown) located in the door closer 26 such that the opening of the double arm arrangement 68 causes the internal piston to compress an oil damping spring (not shown). Upon release of the door 28 , the oil dampening spring causes the door 28 to close and the dampening system regulates the speed at which the door 28 closes. When the external gear 66 of the door closer 26 is rotated in the appropriate direction (i.e., reverse), the door closer 26 operates to open the door 28 .
[0037] When the door 28 opens to the preset angle θ, the control unit 22 detects the angle of the door 28 and sends a signal to the motor 60 to stop further progress. At this point, alternative events can occur. For example, all power to the motor 60 may be ceased and the motor may be returned to starting position as the door closer 26 functions in its normal capacity to close the door 28 thereby providing reverse torque on the limit unit 64 which is translated back through the gear box 62 to the motor 60 . In another embodiment, the motor 60 may be bidirectional and as such, the control unit 22 can instruct the motor 60 to return to its starting position under its own power.
[0038] As the door opening sequence begins, should the door physically encounter any impedance (i.e., obstruction) the result will be a fluctuation in current (i.e., voltage) supplied to the motor 60 . The control unit 22 may be programmed to detect any increase in motor voltage fluctuation and can then send a signal to the motor 60 to cease further operation. In the case of a uni-directional motor, the cease in function signal can operate simply to cut-off the electrical supply to the motor 60 . In the case of a bidirectional motor, the cease and function instruction from the control unit 22 can operate to stop the progress of the motor 60 and return it to its starting position under its own power.
[0039] The control unit 22 , can be programmed to operate, auxiliary electrical devices in a restroom such as lights, exhaust fans, aroma therapy dispensers, or other electronic apparatus that can be enjoyed by an patron I in a restroom. The control unit 22 receives electric power from an external source such as an electrical box or a junction box, a battery, or any other means from which electricity is produced. It will all be appreciated by those skilled in the art that the control unit may be programmed to operate a plurality of automatic door opening devices.
[0040] Many modifications and other embodiments of the invention will come to the mind of one skilled in the art having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. Therefore, it is understood that the invention is not to be limited to the specific embodiments disclosed, and that modifications and embodiments are intended to be included within the scope of the appended claims. | An apparatus for automatically opening a swinging restroom door is provided. The apparatus comprises an actuator, a control unit, and a power assisted drive mechanism that can be connected to an existing door closing mechanism. The actuator comprises a proximity sensor and further comprises a series of iconic symbols corresponding to predetermined proximity zones. The control unit is in electronic communication with the actuator with which signals are exchanged. The power assisted drive mechanism is in electronic communication with the control unit and can be connected to an existing door closing mechanism wherein the actions of the door closing mechanism are reversed and the door is opened. | 4 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a U.S. national stage filing of PCT/US09/30023 filed Jan. 2, 2009, which claims the benefit of U.S. Ser. No. 61/018,565 filed Jan. 2, 2008, all of which are incorporated herein in their entireties.
BACKGROUND
Cardiopulmonary resuscitation (CPR) is a well known and valuable method of first aid. CPR is used to resuscitate people who have suffered from cardiac arrest after heart attack, electric shock, chest injury and many other causes. During cardiac arrest, the heart stops pumping blood, and a person suffering cardiac arrest will soon suffer brain damage from lack of blood supply to the brain. Thus, CPR requires repetitive chest compression to squeeze the heart and the thoracic cavity to pump blood through the body. Very often, the victim is not breathing, and mouth to mouth artificial respiration or a bag valve mask is used to supply air to the lungs while the chest compression pumps blood through the body. The methods of providing oxygenated airflow to the lungs and getting rid of Co2 are referred to as oxygenation and ventilation respectively.
It has been widely noted that CPR and chest compression can save cardiac arrest victims, especially when applied immediately after cardiac arrest. Chest compression requires that the person providing chest compression repetitively push down on the sternum of the victim at 100 compressions per minute. CPR and closed chest compression can be used anywhere, wherever the cardiac arrest victim is stricken. In the field, away from the hospital, CPR may be accomplished by ill-trained by-standers or highly trained paramedics and ambulance personnel. The conventional thinking is that The victim's chest is compressed by the rescuer, ideally at a rate and depth of compression in accordance with medical guidelines, e.g., the American Heart Association (AHA) guidelines.
Traditional CPR is performed by active compression of the chest by direct application of an external pressure to the chest. This phase of CPR is typically referred to as the compression phase. After active compression, the chest is allowed to expand by its natural elasticity which causes expansion of the patient's chest wall. This phase is often referred to as the relaxation or decompression phase. Such expansion of the chest allows some blood to enter the cardiac chambers of the heart. The procedure as described, however, is inefficient to oxygenate the body. Consequently, conventional CPR also requires periodic ventilation of the patient. This is commonly accomplished by a mouth to-mouth technique or by using positive pressure devices, such as a self-inflating bag which delivers air through a mask, an endotracheal tube, or other artificial airway.
In order to increase cardiopulmonary circulation induced by chest compression, a technique referred to as active compression-decompression (ACD) has been developed. According to ACD techniques, the active compression phase of traditional CPR is enhanced by pressing an applicator body against the patient's chest to compress the chest. Such an applicator body is able to distribute an applied force substantially evenly over a portion of the patient's chest. More importantly, however, the applicator body is sealed against the patient's chest so that it may be lifted up to 10% beyond the neutral position to actively expand the patient's chest during the relaxation or decompression phase. The resultant negative intrathoracic pressure induces venous blood to flow into the heart from the peripheral venous vasculature of the patient resulting in better cardiac out put in subsequent compression. Devices and methods for performing ACD to the patient are described in U.S. Pat. Nos. 5,454, 779 and 5,645,552, the complete disclosures of which are herein incorporated by reference.
CPR is often administered in conjunction with other procedures which, taken together, are referred to as advanced cardiac life support (ACLS) for adults and pediatric advance life support (PALS) for children. Most commonly, CPR is administered while the patient undergoes both electrocardiographic monitoring (ECM) and electrical defibrillation. Both ECM and defibrillation require the attachment of electrodes to the patient's chest. The inventors have recognized that the need to attach electrodes can interfere with the ability to administer CPR, particularly the ability to administer manual CPR and give shock to the patient at the same time.
SUMMARY
While devices are available to perform ACD are available, the inventors have recognized certain problems and shortcomings of current devices. The subject invention is based on the inventors' work toward improving ACD devices. Current ACD devices such as that describe in U.S. Pat. No. 5,645,522 and European Patent Pub. 0623334 are hard rigid devices that incorporate a metal suction cup. The suction cup is pressed against a patient's chest and engages to the chest via a vacuum. However, the inventors have realized that such conventional ACD devices apply an inordinate amount of pressure around the periphery of the suction cup. This often leads to undesired tissue damage and lacerations to the chest. Further, due to the rigidity of the device and the pressure applied during CPR, application of such device can and often does fracture the patient's ribs. In one embodiment of the subject invention, the invention pertains to an apparel device such as a glove or mitten designed to be worn on the hands of a medical assistance provider. The apparel device is made of a flexible, soft material and includes a pad located adjacent to the palm area. The pad is engaged to a patient's chest via an adhering material. The adhering material may be an adhesive such as a suitable glue that is preapplied to the pad and covered. Before use, the cover is removed and the pad is pressed upon the patient's chest. Alternatively, adhering material is applied to the pad immediately prior to application of the pad to the patient's chest. In a specific embodiment, the pad may comprise a cover layer, an adhesive layer subjacent to the cover layer, a first a hook and loop layer (e.g. Velcro) subjacent to the adhesive layer, second hook and loop layer subjacent to the first hook and loop layer. The pad is secured to an apparel device body made up of a flexible material. The pad may be secured to the body via an adhesive, sewing, melding, etc. The apparel device will allow a medical assistance provider to easily put on their hand and properly position on a patient's chest and apply ACD while minimizing undesired tissue damage to the patient. Furthermore the implementation of an apparel device for administering ACD is much easier as compared to conventional devices. Utilizing embodiments of the invention leads to significantly longer endurance for sustaining CPR, as well as sustaining highly effective CPR.
The inventors have recognized that current ACD devices are not tailored for administering CPR to infants and small children. In one embodiment, the invention pertains to a device designed for placement on a user's thumbs. The device comprises a first and second body portion that surrounds the thumbs with a pad disposed on each. The pad is designed to adhere to the chest of an infant patient. This embodiment will assist with applying not only CPR on an infant but, more importantly, to apply infant ACD. The user will apply pressure to the patient's chest with their thumbs and pull back with their thumbs. As the user pulls back, the device will pull up and decompress the patient's chest.
As discussed above, CPR is often administered in conjunction with other procedures such as electrocardiographic monitoring (ECM) and electrical defibrillation. Both ECM and defibrillation require the attachment of electrodes to the patient's chest. The inventors have recognized a shortcoming with conventional ACLS strategies and devices in that they require suspension of CPR during a defibrillation event. Defibrillation involves the application and a high voltage electric shock to the thoracic cavity of the patient in an attempt to reset the heart and normalize heart rate. Consequently, medical assistance personnel must suspend the CPR while defibrillation occurs so as to avoid electric shock. This results in a stoppage of CPR for several seconds in a setting where any pause in CPR dramatically decreases the chances of a successful outcome. Accordingly, another embodiment of the invention pertains to an apparel device that includes a pad for adhering to a patient's chest and an electrically insulating layer that allows a medical assistance provider to maintain wear of the apparel device engaged to the patient even upon application of electric shock to patient.
According to another embodiment, the apparel device is adapted as an AED pad or to co-function as an AED pad with the defibrillation machine. The embodiment includes an apparel body for fitting over the user's hand which is connected to or integrated with a pad that includes an electrode. An insulating layer is included between the electrode and the apparel device so as to prevent electric shock to the medical assistance provider.
In another embodiment, the invention pertains to a defibrillation harness such as that shown in FIG. 11 which has an apparel device described herein attached to the center bridge portion. The harness is situated on the patient and the medical assistance provider positions their hand in the apparel device. CPR and defibrillation can be administered to the patient in an efficient and minimally damaging manner. Further, the bridge can be insulated or otherwise avoid the delivery of shock thereby allowing the administration of CPR with minimal interruption.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a side-view image of an ACD device embodiment designed for infants and small children.
FIG. 2 shows a side-view image of the embodiment shown in FIG. 1 on its opposite side.
FIG. 3 shows a side-view image of another embodiment designed for ACD administration to infants and small children.
FIG. 4 shows a side view image of an ACD device embodiment designed for administration of ACD to adults.
FIG. 5 shows a side view image of the embodiment shown in FIG. 4 on its opposite side.
FIG. 6 shows a side view image of an ACD device embodiment designed for administration of ACD to adults.
FIG. 7 shows a side view image of the embodiment shown in FIG. 6 .
FIG. 8 shows a side view perspective image of the embodiment shown in FIG. 3 with a user's thumbs placed therein.
FIG. 9 shows a side perspective image of the embodiment shown FIGS. 4 and 5 with a users hand positioned therein.
FIG. 10 shows an image of a convention AED harness.
FIG. 11 shows a cross-section of a portion of an ACD apparel device embodiment.
FIG. 12 shows a cross-section of a portion of an embodiment of an apparel device.
DETAILED DESCRIPTION
Turning to FIG. 1-2 , what is shown is first and second a side-view images of an ACD apparel device embodiment 100 of the present invention. The apparel device 100 is specifically tailored for administration of ACD to infants and small children. The device 100 includes a first and second thumb holder 102 , 104 connected together and an adhering pad 106 . The user inserts their thumbs into openings 112 and 114 . The device 100 is adhered to a patient's chest via the adhering pad 106 . ACD is applied by applying pressure to the patients chest and pulling back on the chest using the medical assistance provider's thumbs.
An alternative apparel device embodiment 140 is shown in FIG. 3 . This embodiment 140 includes a strap 149 that surround thumbholder lobes 142 , 144 to provide additional support. Both embodiments 100 and 140 are made of a soft flexible material, such as a woven or non-woven fabric, leather, vinyl, flexible plastic, rubber, and the like, or combinations thereof. FIG. 8 shows a user's thumbs positioned with the embodiment 140 .
FIG. 4 shows another apparel device embodiment 120 designed for administering ACD to adults. The embodiment 120 is made of a fabric and is configured as a mitten body 121 . The embodiment 120 comprises an aperture 124 and an aperture 126 for extending a user's fingers and thumb, respectively, through the apparel device 120 . The fingers could be enclosed, but the apertures facilitate interlocking of the user's hands. FIG. 9 shows a users hand positioned with the glove embodiment 120 . The embodiment 120 also includes an adhering pad 124 that adheres to a patient's chest. The embodiment 120 also comprises an adjustable strap that support's the embodiment at the top portion of the user's inserted hand.
FIG. 6 shows an alternative apparel device embodiment 130 configured as an open-ended glove 131 . A user inserts their hand through opening 136 and extends their fingers through openings 135 . Similar to the glove type embodiment, the fingers can be covered, but allowing exposure of the fingers assists in the optimal interlocking of the user's hands. The opening for the thumb is hidden. FIG. 7 shows the palm side 137 of the embodiment 130 . Connected to or integrated with the palm side 137 is an adhering pad 134 . The adhering pad 134 is adhered to a patient's chest prior to administration of ACD.
Though a pad layer of the above described embodiments provides a surface area for adhering the embodiment to the patient's chest, the inventors note that an adhering material could be applied directly on the fabric of the apparel body or thumbholder.
FIG. 10 shows a commercially available defibrillating harness comprising pads 1020 and bridge portion 1021 . The bridge portion 1021 can be adapted to include an apparel device for ACD. The bridge 1021 may be insulated to allow application of electrical current to the pads 1020 without shocking the medical assistance provider.
FIG. 11 shows a cross section of a portion of an insulated apparel device embodiment. According to this embodiment, the apparel device comprises an adhesive pad 1012 with an electrode 1018 embedded therein for monitoring or applying electric shock. An apparel material layer 1016 and an insulating layer 1014 . Alternatively the insulating layer is inside the apparel material layer. FIG. 12 shows a cross section of a portion of an embodiment of an apparel device designed for administering ACD to adults shown, wherein the apparel material layer 1016 is shown, and a cover layer 1015 is provided. An adhesive layer 1012 is subjacent to the cover layer 1015 , a first hook and loop layer 1011 subjacent to the adhesive layer 1012 and a second hook and loop layer 1013 subjacent to the first hook and loop layer 1011 .
EXAMPLE 1
Introduction: AHA 2005 guidelines emphasize complete relaxation during CPR since incomplete chest wall recoil during the decompression phase impedes venous return and decreases mean arterial, coronary and cerebral perfusion pressures. In animals ACD-CPR improves hemodynamics compared with standard CPR (S-CPR). We used a novel, simple and inexpensive Adhesive Glove Device to perform ACD-CPR in a manikin model.
Hypothesis: We hypothesized that ACD-CPR using an Adhesive Glove Device provides better chest decompression compare to S-CPR.
Methods: Laerdal™ Resusci Anne (Adolescent) manikin was modified to digitally record compression pressure(CP), compression depth(CD) and decompression depth (DD). Adhesive Glove Device consisted of an oven mitt modified to expose the fingers and thumb allowing interlocking of the fingers and an adjustable strap for proper fit. A wide Velcro patch was sewn to the palmer aspect of the glove and the counter Velcro patch was glued to an adhesive pad applied to the manikin chest wall. BLS or PALS-certified healthcare providers were prospectively randomized to perform either standard CPR or AGD-ACD-CPR for 5 minutes with 30:2 compression: ventilation ratio using crossover design. During AGD-ACD-CPR subjects were asked to actively pull up during decompression. Subjects were blinded to data recordings. Data (mean±SEM) was analyzed using 2 sided paired t-test; alpha ≦0.05 was considered significant.
Results: None of the 16 subjects using S-CPR achieved complete decompression to baseline. Chest decompression was greater with AGD-ACD-CPR; the mean decompression difference was 0.07±0.02 inches, p=0.003. Despite instructions to pull up, only 50% of AGD group decompressed to or beyond baseline. There was no difference between techniques in CD or CP.
Conclusions: Most rescuers don't achieve complete chest recoil during standard CPR, which may be achieved with use of our simple, inexpensive device.
EXAMPLE 2
Rescuer fatigue during Adhesive Glove Device-Active Compression Decompression-CPR (AGD-CPR).
Introduction: ACD-CPR improves homodynamic compared with standard CPR(S-CPR) in animals, but requires more work. In one study most participants felt that the ACD device was very difficult to use.
Hypothesis: ACD-CPR using our Adhesive Glove device in a manikin model results in more rescuer fatigue.
Methods: Laerdal™ Adolescent manikin was used. Adhesive glove device was a modified oven mitt exposing the fingers and thumb to allow interlocking of fingers and an adjustable strap for proper fit. A wide Velcro patch was sewn on the glove's palmer aspect and a counter Velcro patch was fixed to an adhesive pad applied to chest wall. Health care providers were randomized to perform either S-CPR or AGD-CPR for 5 minutes with 30:2 compression: ventilation ratio using crossover design. AGD-CPR subjects were told to actively pull during decompression. Rescuer heart rate(HR) and respiratory rate(RR) were recorded continuously along with recovery time(RT) for HR/RR to return to baseline and actual compressions delivered per minute. Rescuers reported subjective fatigue using a Likert Scale. Subjects were blinded to data recordings. Data(mean±SD) was analyzed using t-test; p≦0.05 was considered significant.
Results: In 16 subjects, HR at 5 minutes was 134±27 versus 131±23 (S-CPR v AGD-CPR; p=0.21). Similarly, RR at 5 minutes was 28±9 versus 28±6, p=0.34 & RT was 248 ±131 sec versus 316±165 sec with AGD-CPR, p=0.23. Compressions per minute were 90±20 versus 82±22 with AGD-CPR, p=0.02. There was no change in decompression depth over time in either group and no significant difference in subjective estimate of time when it became very difficult to continue CPR because of fatigue.
Conclusions: This study suggests that ACD-CPR using our simple inexpensive device does not result in excessive rescuer fatigue. Fewer actual compressions were given during ACD-CPR, probably because it takes longer to perform decompression. The clinical significance of 8 less compressions per minute needs to be determined.
EXAMPLE 3
Improved Chest Recoil Using a Novel Device for Active Chest Decompressions in Child Manikin CPR.
Introduction: Current CPR guidelines emphasize complete chest recoil. Incomplete chest recoil impedes venous return and thus cardiac output. In animals active compression-decompression CPR (ACD-CPR) improves hemodynamics compared with standard CPR (S-CPR). We developed a novel, simple, inexpensive Adhesive Glove Device (AGD) to perform ACD-CPR.
Hypothesis: It was hypothesized that ACD-CPR using an AGD provides better chest decompression compared to S-CPR in a child manikin without increased rescuer fatigue.
Methods: Laerdal™ Resusci Junior manikin was modified to digitally record compression pressure(CP), compression depth(CD) and decompression depth(DD). AGD consisted of a modified oven mitt exposing the fingers and thumb allowing interlocking. A wide Velcro patch was sewn to the palmer aspect and the counter Velcro patch was glued to the manikin chest wall. Certified healthcare providers (16/group) were prospectively randomized to perform either S-CPR or AGD-ACD-CPR for 5 minutes with 30:2 C:V ratio using crossover design with both one hand(OH) and two hand(TH) techniques. AGD subjects were asked to actively pull up during decompression. Subjects were blinded to data recordings. Rescuer heart rate(HR), respiratory rate(RR), recovery time(RT) and actual compressions delivered per minute were recorded. Data (mean±SEM) was analyzed using 2 sided paired t-test; p-value ≦0.05 was considered significant.
Results: Chest decompression was greater with AGD-ACD-CPR; the mean decompression difference was 0.098±0.02 inches, p=<0.001 in OH and 0.099±0.02 inches, p=<0.001 in TH. Compressions delivered per minute were 85±22 (S-CPR) vs.74±23 (AGD-CPR), p=0.02 in OH group and 92±23 vs. 79±22, p=0.003 in TH. Among AGD-ACD-CPR groups, 56% of subjects in OH and 38% in TH decompressed to or beyond baseline. In S-CPR group, only 12% of subjects in OH and 18% in TH achieved complete chest recoil. No significant difference was observed in CD, CP, HR, RR and RT between the groups.
Conclusions: Use of the easy to use and inexpensive AGD resulted in improved chest decompression with out excessive rescuer fatigue. Most rescuers did not achieve complete chest recoil during standard CPR.
EXAMPLE 4
Active Compression Decompression-CPR in an Infant Manikin Model Using a Novel Adhesive Glove Device.
Introduction: In animals Active Compression-Decompression(ACD)-CPR improves hemodynamics compared with standard CPR (S-CPR). We evaluated the feasibility of achieving ACD-CPR with a novel, simple and inexpensive Adhesive Glove Device(AGD) in an infant manikin model using two thumb(TT) chest compression.
Hypothesis: AGD-ACD CPR provides better chest decompression compared to S-CPR in an infant manikin model without excessive rescuer fatigue.
Methods: Laerdal™ Baby ALS Trainer manikin was modified to digitally record compression pressure(CP), compression depth(CD) and decompression depth(DD). The thumb portion of two oven mitts were sewn together and a Velcro adhesive patch was stitched on the underside with an encircling adjustable strap for proper fit to create the AGD. An interlocking Velcro patch was glued to the manikin chest wall. Sixteen BLS or PALS certified healthcare providers were prospectively randomized to perform either two-thumb S-CPR or AGD-ACD-CPR for 5 minutes with a 30:2 compression:ventilation ratio using a crossover design. During AGD-ACD-CPR subjects were asked to pull up during chest decompression. Rescuer heart rate (HR), respiratory rate (RR), recovery time (RT) for HR/RR to return to baseline and actual compressions delivered per minute were recorded. Subjects were blinded to data recordings. Data (mean±SEM) was analyzed using 2 sided paired t-test; p-value ≦0.05 was considered significant
Results: Chest decompression was greater with AGD-ACD-CPR; the mean DD difference was 0.11±0.02 inches, p=<0.001. Compressions given per minute were 102±21 in S-CPR group vs. 96±16 in AGD-ACD-CPR group, p=0.04. In AGD-CPR 75% and in S-CPR only 12% of subjects achieved complete recoil to or beyond baseline. There was no significant difference in CD, CP, HR, RR and RT between the groups.
Conclusions: Active decompression and improved recoil was achievable with the use of our simple, inexpensive AGD in this infant CPR model. Use of our device did not result in excessive rescuer fatigue compared to S-CPR. The clinical significance of 6 less compressions/minute in the AGD-CPR group needs to be determined.
The disclosures of all cited patent documents, publications and references are incorporated herein in their entirety to the extent not inconsistent with the teachings herein. It should be understood that the examples and embodiments described herein are for illustrative purposes only and that various modifications or changes in light thereof will be suggested to persons skilled in the art and are to be included within the spirit and purview of this application and the scope of the appended claims. | Embodiments provided herein include CPR assisting devices. Certain embodiments pertain to a device that may be adhered to patient's chest to aid in active compression/decompression CPR. The device may be incorporated with the AED pad for implementation in conjunction with defibrillator machine. | 0 |
FIELD OF THE INVENTION
This invention relates to an adduct of a hydrogenated nitrile rubber and a sulfenyl chloride, which adduct is characterized by having a surprisingly low level of insoluble gel.
BACKGROUND OF THE INVENTION
In general, hydrogenated nitrile rubber is produced by the catalytic hydrogenation of the carbon-carbon double bonds contained in nitrile rubber. Vulcanizates of hydrogenated nitrile rubber are known to have excellent resistance to ageing in hot air or hot oil.
It is known to chemically modify hydrogenated nitrile rubber so as to produce a material having characteristics which are particularly well suited for a particular application. For example, U.S. Application Ser. No. 291,964 (filed 30 Dec. 1988, now U.S. Pat. No. 4,879,352) teaches the preparation of hydrogenated nitrile rubber having oxazoline functionality and U.S. Application Ser. No. 239,783 (filed 16 Sept.1988, now U.S. Pat. No. 4,868,881) teaches the preparation of an adduct of hydrogenated nitrile rubber and a halogen.
The modification of hydrogenated nitrile rubber often leads to a polymer which has a high gel content (i.e. as measured by the amount of polymer which is insoluble in methyl ethyl ketone). Polymers having high gel content are normally considered undesirable because they do not mix well with compounding ingredients and because they are difficult to vulcanize.
It is an object of the present invention to prepare an adduct of a hydrogenated nitrile rubber and a sulfenyl chloride, which adduct is characterized by having a gel content of less than 15 per cent.
SUMMARY OF THE INVENTION
The present invention provides an adduct of a sulfenyl chloride and a hydrogenated nitrile rubber, wherein said adduct is characterized by having a gel content of less than 15 weight per cent as determined by the present adduct insoluble in methyl ethyl ketone after 16 hours at 30° C.
DETAILED DESCRIPTION
Nitrile rubber is a well known article of commerce which is typically prepared by the free radical initiated, emulsion polymerization of a C 3 to 5 α,β-unsaturated nitrile and a C 4 to 6 conjugated diene. Nitrile rubber has carbon-carbon double bond unsaturation resulting from the incorporation of the conjugated diene units. Acrylonitrile-butadiene rubber is a commercially available example of nitrile rubber.
As used herein, the term "hydrogenated nitrile rubber" refers to the product which is obtained by hydrogenating the carbon-carbon unsaturation of nitrile rubber until the remaining level of double bond unsaturation is less than 10 mole per cent. Preferred hydrogenated nitrile rubber has less than 5 mole per cent double bond unsaturation and is most preferably prepared by hydrogenating an acrylonitrile-butadiene rubber. In particular, the preferred acrylonitrile-butadiene rubber contains (prior to hydrogenation) 18 to 50 weight per cent acrylonitrile units (especially from 25 to 45 weight per cent acrylonitrile units) with the balance to 100 weight per cent consisting of butadiene units.
Hydrogenated nitrile rubber may be produced by the catalytic hydrogenation of a solution of nitrile rubber. Hydrido tetrakis (triphenylphosphine) rhodium (I), for example, is a suitable hydrogenation catalyst for nitrile rubber. Detailed descriptions of nitrile rubber hydrogenation processes are provided in U.S. Pat. Nos. 4,464,515 and 4,631,315, the disclosures of which are incorporated herein by reference.
Hydrogenated nitrile rubber is commercially available under the trademarks THERBAN® (from Bayer, of Leverkusen, West Germany), ZETPOL® (from Nippon Zeon, Japan) and (produced by Polysar, in Orange, Tex., U.S.A.).
The present invention relates to certain adducts of a hydrogenated nitrile rubber and a sulfenyl chloride.
The term "sulfenyl chloride" is meant to refer to its conventional meaning, namely a compound represented by the formula
RSCl
where S is sulfur, Cl is chlorine and R is an organic moiety.
It is preferred to utilize a sulfenyl chloride in which the organic moiety R contains from 8 to 30 carbon atoms, because a sulfenyl chloride having a lower molecular weight tends to provide a foul smelling adduct and a sulfenyl chloride having a higher molecular weight is difficult to utilize. The organic moiety R may suitably be fluoro substituted.
The structure of the organic moiety R is also of some significance. It is especially preferred to utilize a sulfenyl chloride in which the sulfur atom is chemically bonded to a primary carbon atom, because this structure has been observed to generally provide adducts having a low gel content.
Highly preferred sulfenyl halides for use in the present invention are alkyl sulfenyl halides and perfluoro-alkyl sulfenyl halides.
While not wishing to be bound by any theory, it is believed that the sulfenyl chloride reacts with residual carbon-carbon double bond unsaturation in hydrogenated nitrile rubber as follows: ##STR1##
Formula (I) suggests that an analogous sulfenyl bromide (i.e. RSBr) should provide a similar result. However, sulfenyl bromides are not suitable for use in the present invention because, for reasons which are not understood, it was not found possible to prepare an adduct of hydrogenated nitrile rubber and a sulfenyl bromide which had a low gel content.
Formula (I)also indicates that the preparation of the adducts of the present invention eliminates some of the residual double-bond unsaturation contained in the hydrogenated nitrile rubber. However, it is highly desirable that the present adducts contain some residual double-bond unsaturation to provide sites which facilitate vulcanization. Accordingly, the adducts of the present invention should contain from 0.05 to 0.9 moles of sulfenyl chloride per mole of double bond unsaturation which was originally contained in the hydrogenated nitrile rubber.
Sulfenyl chlorides may be readily and conveniently prepared according to methods which are widely reported in the literature. The chlorination of thiols and the cleavage of disulfides with chlorine are two well known methods to prepare sulfenyl chlorides.
The adducts of the present invention may be conveniently prepared by mixing a suitable sulfenyl chloride with a solution of hydrogenated nitrile rubber. The adducts may be mixed with conventional rubber compounding ingredients and vulcanized. It is especially preferred to utilize adducts having less than 5 weight % gel to facilitate the compounding and vulcanization processes.
Further details of the invention are given in the following examples, in which all references to parts and percentages are by weight, unless otherwise indicated.
EXAMPLE 1
Sulfenyl chlorides were prepared by reacting chlorine with a thiol or disulfide of the type indicated in Table 1.
The procedure used to prepare the sulfenyl chlorides is described below.
A solution of chlorine in carbon tetrachloride (solution concentration=3.5 g Cl 2 /100 ml CCl 4 ) was added under a nitrogen atmosphere to a 3 necked, 500 ml flask in the quantity indicated in Table 1.
A solution of thiol or disulfide in CCl 4 was then added dropwise to the 500 ml flask. The contents of the flask were then stirred under a nitrogen atmosphere at room temperature for 30 minutes.
The thiol (or disulfide) solution contained 50 ml of CCl 4 and the quantity of thiol or disulfide indicated in Table 1. The contents of the flask were then stirred under a nitrogen atmosphere at room temperature for 30 minutes. Excess chlorine was removed from the system by exposing the flask contents to a vacuum (10-15 mm Hg). The resulting sulfenyl chloride was then used in the preparation of hydrogenated nitrile rubber adducts, as described in Example 2.
TABLE 1______________________________________ Quantity of Quantity of Thiol or Thiol or Cl.sub.2 /CCl.sub.4Experiment Disulfide Disulfide (g) solution (ml).sup.a______________________________________E-35 C.sub.18 H.sub.37 SH 10.5 100E-45 (HO.sub.2 CCH.sub.2 CH.sub.2 S).sub.2 4.4 75E-65 MeOC.sub.6 H.sub.4 CH.sub.2 SH 5.7 100E-72 C.sub.6 F.sub.13 C.sub.2 H.sub.4 SH 13.9 100E-81 (MeO).sub.3 Si(CH.sub.2).sub.3 SH 7.2 100E-102 C.sub.6 H.sub.4 (NOC)SH 5.8 100E-122 (HO.sub.2 CCH.sub.2 CH.sub.2 S).sub.2 2.4 50______________________________________ Notes: .sup.a solution concentration = 3.5 g Cl.sub.2 /100 ml CCl.sub.4
EXAMPLE 2
This example illustrates the preparation of adducts of hydrogenated nitrile rubber and sulfenyl chloride.
Two types of hydrogenated nitrile rubber were used in the experiments of this example. The hydrogenated nitrile rubber noted as A in Table 2 was prepared from an acrylonitrile/butadiene rubber (38% acrylonitrile/62% butadiene) and was hydrogenated to the extent that it contained only 9 mole % carbon-carbon double bond unsaturation. The hydrogenated nitrile rubber noted as B in Table 2 was also prepared from a similar starting acrylonitrile/butadiene rubber (35%/62%) but was hydrogenated to a greater extent (such that it only contained b 4 mole % carbon-carbon unsaturation).
Adducts of HNBR and sulfenyl chloride were then prepared according to the following procedure.
A rubber solution containing 10 grams of hydrogenated nitrile rubber and 140 grams of monochlorobenzene was prepared and added to a 500 ml flask. While stirring the rubber solution at approximately 500 revolutions/minute, a solution of sulfenyl chloride in CCl 4 (as described in Table 2) was added to the flask. Solutions which were not visibly gelled were worked up by coagulation with methanol and drying under vacuum.
The gel content of an adduct was indirectly determined by measuring the solubility of the adduct in methyl ethyl ketone ("MEK"), as indicated by the formula: ##EQU1## Table 2 shows that the adducts of Experiments 4, 5, 6, 9, 10, 11, 12, 13 and 14 contain more than 15 weight % gel and hence are outside the scope of the present invention. Conversely, the adducts of Experiments 1, 2, 3, 7, 8 and 15 have surprisingly low gel levels.
The amount of carbon-carbon unsaturation remaining in the adducts, as determined by infra-red spectroscopy, is also shown in Table 2.
The amount of chlorine, sulfur and fluorine (where applicable) of some of the adducts was determined by elemental analysis. The adduct of Experiment 7 was found to contain 5.2% Cl, 2.4S and 14.6% F. The adduct of Experiment 8 was found to contain 1.4% Cl, 1.7% S and 5.8% F.
TABLE 2__________________________________________________________________________ Rubber Thiol.sup.1 or Quantity of Thiol or Unsats GelExperiment Type Disulfide Disulfide (moles) (mole %) (wt. %)__________________________________________________________________________ 1 A C.sub.18 H.sub.37 SH 0.0198.sup.2 0.3 <1 2 A " 0.0086.sup.2 2.4 <1 3 B " 0.0086.sup.2 0.4 <1 4-c A (HO.sub.2 C(CH.sub.2).sub.2 S).sub.2 0.0231.sup.2 2.4 gel 5-c B " 0.0139.sup.2 0.5 gel 6-c A MeOC.sub.6 H.sub.4 CH.sub.2 SH 0.0113.sup.2 n.m. gel 7 A C.sub.6 F.sub.13 C.sub.2 H.sub.4 SH 0.0169.sup.3 0.2 3.2 8 B " 0.0100.sup.3 0.2 3.6 9-c A (MeO).sub.3 Si(CH.sub.2).sub.3 SH 0.0148.sup.2 n.m. gel10-c B " 0.0148.sup.2 n.m. gel11-c B " 0.0185.sup.2 n.m. gel12-c B C.sub.6 H.sub.4 (NOC)SH 0.0025.sup.2 n.m. gel13-c B " 0.0013.sup.2 2.4 72.714-c B " 0.0013.sup.2 n.m. 66.715 B (HO.sub.2 C(CH.sub.2)S).sub.2 0.0040.sup.2 2.1 3.4__________________________________________________________________________ Notes: c = comparative .sup.1 used to prepare the sulfenyl halide .sup.2 added as a solution in 50 ml CCl.sub.4 .sup.3 added as a solution in 100 ml CC.sub.4 "n.m." not measured "gel" grossly gelled "<1" less than 1 weight % | The present invention provides an adduct of a hydrogenated nitrile rubber and a sulfenyl chloride.
The adducts are characterized by having a surprisingly low level of gel, as determined by the amount of adduct which is insoluble in methyl ethyl ketone after 16 hours at 30° C.
The adducts may be vulcanized and used to prepare seals, gaskets or mechanical goods. | 2 |
BACKGROUND OF THE INVENTION
The present invention is directed to electrolytic cells and more particularly to electrolytic cells containing a bipolar type electrode wherein the electrical current is transferred from the anolyte element to the cathode element within the cell in a fluid-tight manner. Although the present invention is particularly directed to bipolar cells, it is also useful in other types of electrolytic cell as will be apparent to those skilled in the art.
This invention is particularly well-suited for use in joining components of an electrolytic cell, e.g., anode and cathode plates, in a fluid-tight cell. The electrolysis of ionizable chemical salts, e.g., alkali metal halides, to yield useful basic staple chemical products, e.g., alkali metal hydroxides, halogen and hydrogen has long been practiced commercially. For example, such electrolysis has been carried out in diaphragm cells wherein there are two compartments separated by a porous diaphragm. One compartment contains the cathode and the other contains the anode with the electrolyte flowing from the anode compartment through the porous diaphragm into the cathode compartment completing the electrical circuit. A variation of such a two compartment cell, called a filter press arrangement, is one wherein a large number of cells are connected in series in a common housing. According to such a variation, the anode of one cell is connected electrically with a cathode of an adjacent cell with these cells being separated by a barrier serving to prevent the passage of electrolyte between the adjacent cells. Such a configuration is termed a bipolar electrode, and the series of cells is called a bipolar type filter press cell.
The provision of efficient electrode connections between the anode and cathode elements are components of adjacent cell units is important. However, obtaining efficient electrical contacts which are both compact, liquid and gas tight and capable of ready removal for maintenance of the other components of the cell can be a troublsome and elusive goal, particularly where there is a high density current flow within the electrolytic cell. There have been many patents directed to provision of various fluid-tight electrical contacts and connections for electrolytic cells. U.S. Pat. No. 3,429,799 to R. W. McWhorter is directed to a fluid-tight electrical connector for connecting anode and cathode electrodes 20 and 42. The electrical connector comprises a flanged cylindar 32 with an axial bore 24 therein and the bore contains a soft metal filler material which can be integrally joined to electrode 20 as by welding.
U.S. Pat. No. 3,788,966 issued to C. W. Stephenson III et al discribes an electrical connection for metal electrodes formed by coating each connector part with a layer of softer but compatible, nonoxidizing metal and joining the connector parts together by exersion of a shearing stress as the male and female bolt connector parts are joined together during the bolting procedure.
U.S. Pat. No. 3,824,173 to P. Bouy et al shows a ring 5 which electrically connects an anode plate 6 and cathode 8. Ring 5 carries resilient plate members (not numbered) on its inner and outer surfaces, and these plates electrically interconnect parts 1 and 2. Parts 1 and 2 in turn are electrically connected to the anode and cathode plates. The annular surface of the ring makes the electrical contact as opposed to the end surfaces (edges) of the substantially concentric spirals or rings of the electrical contact device of this invention.
U.S. Pat. No. 3,859,197 to P. Bouy et al is directed to bipolar electrodes wherein the two electrically active parts are apertured, and the electrical connection between is made through the electrical contact formed within a plurality of bonded, e.g., welded members produced by plating a metal which can be used cathodically with a film-forming metal, and then using the bonded members as part of a sealing partition separating the two electrically parts.
U.S. Pat. No. 3,915,833 to S. A. Michalek et al discribes an electrical contact made between the mating surfaces of the anode and cathode bosses by coating a valve metal anode boss with platinum and the ferrous metal or a nickel cathode boss surface with a soft metal such as copper. A soft metal gasket is placed between the bolt head and the pressure receiving shoulder of the boss through which the bolt passes.
U.S. Pat. No. 3,950,239 issued to W. E. Figueras shows a bipolar plate having an electrical connector which comprises a rod 9 which extends between an anode plate 1 and cathode plate 3. This rod is threadibly secured within cylindar 5 and is electrically connected to caps 5 and 10 which, in turn, are electrically connected with the anode and cathode plates.
U.S. Pat. No. 4,022,952 issued to D. H. Fritts utilizes a porous metal matrix 21 to electrically interconnect metal grids 22 and 23 and therefore electrically connect cathode 24 with anode 25. The porous metal matrix is filled with a heat sink material.
U.S. Pat. No. 4,026,782 to P. Bouy et al utilizes an elastically deformable sealing member resting against a diaphragm and arranged in the recess of an adjacent frame. The elastically deformable member is arranged in a housing made in the recess and has a shape, e.g., toroidal, retangular, etc., which is adapted to the configuration of the sealing member.
U.S. Pat. No. 4,085,027 issued to K. A. Pousch describes a fastener assembly 16 comprising a bolt member 74 and nut member 80 which are electrically conductive thereby providing an electrical connection between an anode plate 12 and cathode 14.
U.S. Pat. No. 4,105,529 issued to Gerald R. Pohto (inventor herein) illustrates a helicoil electrical connector aligned between conductive bars so that the longitudinal axis of the connector is parallel to the bars. No filler seal material is employed.
U.S. Pat. No. 4,108,752 issued to G. R. Pohto illustrates the use of a variety of electrical connectors for electrically connecting bipolar plates. The electrical connector (C) can be of a variety of configurations, e.g., in the form of a conductive strip having louvers extending outwardly of the planar faces of the strip (C) in alternating pairs outwardly of one face (louvers 50) or the other (louvers 52) of the conductor strip. As can be seen from FIG. 6, louvers 52 establish contact between parallel surfaces abutting thereto. FIG. 7 illustrates an undulate configuration for conductor strip (C) whereas FIG. 8 shows an askew helix-shaped electrical connector which is aligned between the plates so that its longitudinal axis is parallel to the face of the plates. This is in contrast to the contact device of the present invention wherein the longitudinal axis of the spiral (and the edges thereof) are perpendicular to the face of the electrode plate.
U.S. Pat. No. 4,116,805 issued to Ichisaka et al illustrates bipolar plates 2 and 3 electrically connected by a pin 19.
Also there is currently available on the market a gasket which applicant has utilized in the present invention to form an electrical contact. This gasket is marketed under the trade designation "SPIROTALLIC" and "FLEXITALLIC" and is of the spiral-wound type having a variety of filler materials, such as asbestos, PTFE (polytetrafluoroethylene) of both the solid and nonsintered variety. The "FLEXITALLIC" and "SPIROTALLIC" gaskets are advocated for use as a gasketing material in aircraft, diesel, gas and rocket engines; boiler feed, centrifugal, condensate, reciprocating and vacuum pumps; gauge and sight glasses; centrifugal and reciprocating compressors; high pressure and soot blowers; hydraulic and molding presses; gas and steam turbines; heat exchangers; high voltage power transformers; and all types of valves. In general, these gaskets are described as suitable for use in nonstandard joints and piping systems and pressure vessels.
Applicant has surprisingly discovered that these gasket materials of the spiral-wound spring variety are highly useful as fluid and air tight, electrical contact devices for conductively joining electrolytic cell anode and cathode plates particularly wherein there is a high current density electrolysis being conducted in such cells.
BRIEF SUMMARY OF THE INVENTION
The present invention is directed to fluid-tight, high current density-stable electrical contacts for conductively joining components of an electrolytic cell, e.g., anode and cathode plates, comprising a spring-like spiral or coil of electroconductive metal or metal alloy having an electrically conductive or nonconductive oxidation-resistant filler (seal) between the spiral rings and wherein said spiral rings are positioned so that their edges and common longitudinal axis are substantially perpendicular to the faces of the cell components. It has been determined that the aforementioned electrical contact provides extremely low voltage loss during operation and adjustment for flatness tolerances due to its acting as a spring contact between two plates such as are employed in a bipolar cell. Additionally the present invention provides a contact junction which does not degrade due to overheating and oxidation, such as does occur utilizing aluminum busbars. The present invention provides an improved junction for aluminum surfaces which normally tend to degrade due to formation of aluminum oxide. Moreover, the contact device of this invention provides a high load (amperage) junction which can be easily disassembled for anode recoating or other maintenance. The present invention has the ability to carry higher current densities than traditional flat plate junctions or lighter spring contacts and offers economy of space and material in addition to being a contact device which is comparatively simple to fabricate. It has also been observed that the contact device of this invention is self-protecting from corrosion in as much as its sharp, knife edges offer intimate contact with the electrode sheets thus preventing oxidation while at the same time transmitting electrical contact with continuous electrical transfer. It should be observed that the contact devices of this invention can be fabricated to any desired spring constant, current load and deflection range which is desired by modifying the gauge of the coil or spiral, the number of coils present, the height, the spiral diameter, the bend, the material, or the heat treatment employed as well as many other parameters to suit the connection size desired. Additionally, the present invention offers a junction device which can be used in place of bimetal plates (explosion bonded) in as much as the latter are exposed to atomic hydrogen and frequently separate because of molecular hydrogen build-up at the interface.
DETAILED DESCRIPTION OF THE INVENTION
The invention will be illustrated further in conjunction with the accompanying drawings in which
FIG. 1 is a cross-sectional view showing the contact device of this invention in place serving as an electroconductive contact in an electrolytic cell, and
FIG. 2 is a cross-sectional view illustrating the contact device used in a boss-to-boss contact in a bipolar membrane cell.
According to FIG. 1, electrolytic cell 10 is comprised of major components being an anode 13 located in anode compartment 11 and cathode 14 located in corresponding cathode compartment 12. The electrical contact device of this invention is comprised of a spring-like spiral or coil comprised of spirals 15 having a nonconductive, oxidation-resistant filler or seal material 16 positioned between the respective spirals or coils 15. The upper edges U and lower edges L of the respective spirals 15 contact the lower portion of the anode plate 13 and the upper portion of the cathode plate 14, respectively. Bolt or screw 17 can be employed by inserting it through the appropriate opening in both the anode and cathode plates and serves to press the anode and cathode plates inner surfaces against the upper and lower edge surfaces of the contact device of this invention. Washers 20 can be used in conjunction with nut 19 to effect this pressure which can assist bringing the aforementioned upper and lower edges, U and L, of the contact device in contact with the lower surfaces of the anode 13 and the upper edge surfaces of the cathode plates 14 respectively. Hydrogen vents 21 can be provided.
In accordance with FIG. 2, the spiral contact device of this invention 39 is used for establishing boss-to-boss electrical contact assembly in a bipolar membrane cell. Boss-to-boss contact assembly 30 is located between adjacent cell membranes 31, e.g., made of "NAFION" marketed by DuPont. Flat stand-off bars 32 are welded to the anode e.g., titanium, boss 37 and the cathode, e.g., stainless steel, boss 38 at weldments 41. Similar weldments 41 respectively join the anode boss 37 to anode compartment wall sections 33 and the cathode boss 38 to cathode compartment wall sections 34. Assembly 30 is thus positioned partially in and between anolyte compartment 35 and catholyte compartment 36. The spiral contact device of this invention 39 is securely held between and in contact with the anode boss 37 and cathode boss 38 by high strength, caustic resistant stainless steel or nickel bolt 40. O-ring 42 which can be made of rubber, e.g., "BUNA-N" or elastomer material, e.g., "EPDM" (a polymer of ethylene-propylene diene monomer) completes the assembly.
The copper spiral 15 employed in accordance with this invention can be fabricated from a variety of electrically-conductive materials. Suitable materials for this purpose include, but are not necessarily limited to: copper and copper alloys, such as, beryllium-copper; copper-nickel-tin, e.g., "spinodal 770" (77 Cu-15Ni-88SNn); phosphor-bronze; brass; aluminum alloys; monel; copper-plated spring steel; copper and other metal laminates; roll-bonded layers, and other equivalent materials.
The filler or seal material 16 which is employed between the various spirals of the contact device of this invention can be made of any nonconductive or conductive, oxidation-resistant material. Suitable nonconductive, oxidation resistant filler (seal) materials which can be used include, but are not necessarily limited to, the following: polytetrafluoroethylene in powder form or with or without chopped glass fibers as in a powder/glass fiber matrix; polytetrafluoroethylene in fibrous form (fibrillated or unfibrillated); chopped asbestos; aramide polymers, e.g., the aromatic polyamid polymer marketed by the duPont de Nemours & Company under the trade designation "Kevlar," either in fibrous or nonfibrous form and whether fibrillated or not, e.g., in the form of powder or fibrous matrices containing such aramide polymer material; polyvinyl chloride polymers; fiberglass; etc. In some circumstances, it may be desirable to utilize filler (seal) material which is partially or comparatively fully electroconductive. For this purpose, carbon fibers can be utilized, e.g., graphite fibers. In general, fibers and/or fibrous-containing composites can be used, e.g., "Grafoil"; silver-plated copper strands; nickel fibers; stainless steel fiber wool; etc.
It has been recognized for many years that successful mechanical junction of two electrical components requires the ability to maintain a continuous and high contact pressure and not necessarily over a large area of contact. Various types of springs have been used to maintain this pressure. For example, a standard coil compression spring is often used to press two flat contacts together. Similarly a cantilever spring is used to both carry the current and create the pressure at its tip.
The merit to the spiral spring utilized according to this invention is its ability to maintain unusually high loads with a very small deflection range. Also as the deflection changes (as to adjust itself for temperature expansion), the magnitude of the load does not vary significantly. In other words, it has a flat curve plotting load (pounds) versus deflection. It is the maintenance of this edge load on the spring in accordance with this invention that prevents oxidation, and therefore prevents a voltage build-up due to increase in ohmic resistance of the joint.
In accordance with this invention, the filler material is used to both support the parallel (or concentric) coils of the spiral and to exclude any corrosion materials as well as air (oxygen). It is clear that advanced oxidation cannot occur if oxygen is excluded from the contact.
The filler material employed herein must have good hydraulic compression characteristics such as possessed by elastomers, rubber, etc., e.g., EPDM (ethylene-propylene diene rubber), neoprene, BUNA-N, etc. It must not, however, break down under a high compression load because the oil or gas given off, due to breaking down, might react with the copper. It also must have reasonable temperature resistance. For some contact devices, a filler (seal) containing or comprised of a material selected from the group consisting of rubber, elastomers and polytetrafluoroethylene is preferred. Other suitable filler materials include, but are not necessarily limited to, the following: blue-dyed Canadian asbestos paper; white-dyed Canadian asbestos paper; white-dyed Canadian asbestos paper with an inorganic binder or a rubber, e.g., "BUNA-N" PTFE (polytetrafluoroethylene); or Neoprene binder; glass-filled PTFE; "Grafoil", viz., a commercially available compressed graphite matrix paper marketed by the Union Carbide Corporation, etc. | The present invention is directed to fluid-tight, high current density-stable electrical contacts for conductively joining components of an electrolytic cell, e.g., anode and cathode plates, comprising a spring-like spiral or coil of electroconductive metal or metal alloy having an electrically conductive or nonconductive oxidation-resistant filler (seal) between the spiral rings and wherein said spiral rings are positioned so that their edges and common longitudinal axis are substantially perpendicular to the faces of the cell components. | 2 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] The current application claim benefit and priority of U.S. Provisional Patent Application No. 61/502407, filed on Jun. 29, 2011, the entire content of which is incorporated herein by reference in its entirety.
BACKGROUND
[0002] The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
[0003] Material that has accumulated in a wellbore before or during completion is often called wellbore fill; it may be sand, proppant, cement chunks, or other materials. Such materials hinder or prevent operations. Sand accumulated in production tubing in a wellbore at the start of or during production can greatly hinder production. Coiled tubing has been widely used as a means to clean out the wellbore or production tubing in these situations and to remove wellbore fill. Such cleanout operations utilize fluids pumped down the wellbore through the coiled tubing to pick up solid particles and then to transport the particles back to the surface.
SUMMARY
[0004] 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.
[0005] In some embodiments, there is a method of treating a wellbore or a subterranean formation penetrated by a wellbore including the steps of preparing a gelled oil at the surface, performing a first cycle including a series of steps including injecting the gelled oil into a well, recovering the gelled oil at the surface, reducing the viscosity of the gelled oil by adding a first pH-adjusting agent, treating the gelled oil having reduced viscosity, increasing the viscosity of the gelled oil by adding a second pH-adjusting agent, and starting a second cycle by re-injecting the gelled oil into the well. In various embodiments, the injection is through coiled tubing; the gelled oil is made with a hydrocarbon mixture, a gelling agent, and a crosslinking agent; the treatment is wellbore cleanout; the treatment is drilling; the step of treating the gelled oil having reduced viscosity is a method of removing solids from the gelled oil having reduced viscosity; the first pH-adjusting agent is a base or mixture of bases; the second pH-adjusting agent is an acid or mixture of acids; the gelled oil is made with (a) diesel, (b) a phosphate ester and (c) a ferrous compound, a ferric compound or an aluminum carboxylate; and the step of increasing the viscosity of the gelled oil includes adding a gelling agent, a crosslinking agent, or both.
[0006] In some embodiments, there is a method of cleaning out a wellbore penetrating a subterranean formation comprising injecting a gelled oil into the wellbore, entraining a solid from the wellbore, recovering the gelled oil at the surface, removing the solid from the gelled oil by adding a first pH-adjusting agent to reduce the viscosity of the gelled oil, increasing the viscosity of the gelled oil by adding a second pH-adjusting agent, and re-injecting the gelled oil into the well. In various embodiments, the injection is through coiled tubing; the gelled oil is made with a hydrocarbon mixture, a gelling agent, and a crosslinking agent; the treating the gelled oil having reduced viscosity is a method of removing solids from the gelled oil having reduced viscosity; the first pH-adjusting agent is a base or mixture of bases; the second pH-adjusting agent is an acid or mixture of acids; the gelled oil is made with (a) diesel, (b) a phosphate ester and (c) a ferrous compound, a ferric compound or an aluminum carboxylate; and the step of increasing the viscosity of the gelled oil includes adding a gelling agent, a crosslinking agent, or both.
[0007] In some embodiments, there is a wellbore cleanout fluid comprising a gelled oil with variable viscosity depending on pH. In various embodiments, the gelled oil may comprise a hydrocarbon mixture, a gelling agent, and a crosslinking agent; the wellbore cleanout fluid may comprise (a) diesel, (b) a phosphate ester and (c) a ferrous compound, a ferric compound or an aluminum compound.
DETAILED DESCRIPTION
[0008] It should be noted that in the development of any actual embodiments, numerous implementation-specific decisions may be made to achieve the developer's specific goals, for example compliance with system- and business-related constraints, which can vary from one implementation to another. Moreover, it will be appreciated that such a development effort might be complex and time consuming but would nevertheless be a routine undertaking for those of ordinary skill in the art having the benefit of this disclosure.
[0009] The description and examples are presented solely for the purpose of illustrating embodiments and should not be construed as a limitation to the scope and applicability. Embodiments may be described in terms of treatment of vertical wells, but are equally applicable to wells of any orientation. Embodiments may be described for hydrocarbon production wells, but it is to be understood that embodiments may be used for wells for production of other fluids, such as water or carbon dioxide, or, for example, for injection or storage wells. It should also be understood that throughout this specification, when a concentration or amount range is described as being useful, or suitable, or the like, it is intended that any and every concentration or amount within the range, including the end points, is to be considered as having been stated. Furthermore, each numerical value should be read once as modified by the term “about” (unless already expressly so modified) and then read again as not to be so modified unless otherwise stated in context. For example, “a range of from 1 to 10” is to be read as indicating each and every possible number along the continuum between about 1 and about 10. In other words, when a certain range is expressed, even if only a few specific data points are explicitly identified or referred to within the range, or even when no data points are referred to within the range, it is to be understood that the inventor appreciates and understand that any and all data points within the range are to be considered to have been specified, and that the inventor has possession of the entire range and all points within the range.
[0010] The statements made in this paragraph merely provide information related to the present disclosure and may not constitute prior art, and may describe some embodiments illustrating the claimed subject matter. Water-based treatment fluids can damage some wellbores and formations; embodiments described relate to oil-based fluids having recyclable viscosity and their use in oilfield treatments. More particularly, they relate to compositions and methods for cleaning debris from wellbores and wellbore tubing. Even more particularly, they relate to methods and compositions for recycling a gelled hydrocarbon fluid used in such coiled tubing cleanout operations. The recyclable gelled oil fluid is particularly suitable for coiled tubing cleanout applications because the gelled oil is still quite clean when it flows back. The recyclable gelled oil is suitable for other applications too such as frac jobs. To be effective at entraining and carrying solid particles, fluids used in cleanout operations are often viscosified. Most typically, however, these viscosified fluids are discarded after a single trip through the well because removal of the entrained solids from the fluid either requires a long settling time or the addition of a chemical breaker to reduce the fluid viscosity. Additional requirements for fluids used for wellbore fill removal, more particularly coiled tubing cleanout, include low friction pressure and good particle carrying capability. Some crosslinked polymer gels are not used as viscosifiers for cleanout fluids because they do not have appropriate viscoelastic properties for suspending the particles so that they can be transported.
[0011] Gelled oil can be used for wellbore or production tubing cleanout with coiled tubing, the viscosity of the baseline gelled oil can then be reduced to a nearly water-like value (from about 1 cP to about 10 cP is suitable) to drop out the entrained solids by sufficiently increasing the pH (the amount of base and the necessary pH depend upon many factors, including the nature of the components, their concentrations, the mixing energy, the size, shape, concentration and density of the suspended solids, the extent to which the solids must be removed, and the temperature), and the gelled oil can then regain most of the original viscosity if the pH is then decreased to close to its original value. Suitable bases that may be used to increase the pH include, but are not limited to, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, ammonium hydroxide, and others; non-limiting examples of suitable acids for regenerating the lost viscosity include hydrochloric acid (HCl), sulfuric acid, formic acid, acetic acid, lactic acid, citric acid, and others. Note that for simplicity I may describe adding an acid or base to a hydrocarbon mixture as changing the pH, even though the mixture, and optionally the acid and/or base, may initially contain no water. Dilution, especially by water, may reduce the viscosity of gelled oils, so changes in pH may be brought about by solid or concentrated acids or bases as much as possible to increase the number of cycles in which a given batch of gelled oil may be used. For water-sensitive gelled oils, non-aqueous pH-adjusters, for example alkali metal alkoxylate in the corresponding alcohols may be used.
[0012] The gelled oil, as described here, can be used as the carrier fluid for coiled tubing cleanout jobs, for example before or after completion or cementing, or for removal of particulates (such as proppant or formation sand) after stimulation or during production. To pick up and carry wellbore fill, the gelled oil needs to be sufficiently viscous. The necessary viscosity depends upon the gelled oil flow rate (pumping rates) or concentration of sand/proppant/gravel; lower flow rates or higher fill concentration and/or densities require greater viscosity. Once the fill is transported to the surface, for optimal efficiency the fill should be separated quickly from the carrier fluid. If the gelled oil still has high viscosity, it will be difficult to separate the fill from the gelled oil. When the pH is adjusted, the gelled oil is quickly broken into a low-viscosity water-like or close to water-like liquid, and the fill quickly precipitates to the bottom of the broken gelled oil due to gravity, and can be easily collected and removed. Once the fill is separated and removed, an acid, for example HCl, is added, and the broken gelled oil changes back into a viscous gelled oil, and can be recycled and used in the cleanout job again. This way, there is provided a recyclable or reusable carrier fluid.
[0013] The base gelled oil fluids are substantially or entirely hydrocarbons. In some embodiments, the base fluid is diesel, which is typically a mixture of aromatics and saturated and unsaturated aliphatics, and which may contain trace amounts of compounds containing oxygen, sulfur, and nitrogen. Other suitable base fluids include, for example, kerosene, paraffinic oil, ether, crude oil, condensate, toluene, xylene, and mineral oil, biodiesel, limonene and mixtures thereof. Compared with aqueous crosslinked polymers, gelled oil systems use fewer additives, usually are expected to be insensitive to pH, and cause less damage to formations because they contain no polymers. The hydrocarbon is gelled with a gelling agent (for example an organic carboxylate, a phosphate ester, for example an alkyl phosphate ester) and a crosslinking agent (sometimes called an activator), such as certain aluminum or ferric or ferrous compounds (for example a metal carboxylate, for example an aluminum carboxylate, or a ferric ammonium citrate or ferric alkylamine citrate). Optionally, the oil may be gelled with an aluminum salt of a phosphate ester; or a polyvalent metal salt of an organophosphonic acid ester or a polyvalent metal salt of an organophosphinic acid; or a polyvalent metal salt of an organophosphonic acid ester or a polyvalent metal salt of an organophosphonic acid. Gelled oils, gelling agents and crosslinkers or activators, and batch and continuous methods of preparing suitable gelled oils, are well known to those of skill in the art of subterranean reservoir treatment.
[0014] A fiber component may be included in the gelled oil fluids used in the current disclosure to achieve a variety of properties including improving particle suspension, and particle transport capabilities, and gas phase stability. Fibers used may be hydrophilic or hydrophobic in nature. Fibers can be any fibrous material, such as, but not necessarily limited to, natural organic fibers, comminuted plant materials, synthetic polymer fibers (by non-limiting example polyester, polyaramide, polyamide, novoloid or a novoloid-type polymer), fibrillated synthetic organic fibers, ceramic fibers, inorganic fibers, metal fibers, metal filaments, carbon fibers, glass fibers, ceramic fibers, natural polymer fibers, and any mixtures of these. Other examples of useful fibers include, but are not limited to, polylactic acid polyester fibers, polyglycolic acid polyester fibers, polyvinyl alcohol fibers, and the like. Fibers will attach to proppants or particles and drop out with them, aiding their removal; fresh fibers are added in each cycle.
[0015] The gelled oil fluids may additionally contain a viscoelastic surfactant (VES), for example as described in U.S. Pat. No. 7,521,400 to provide an increase in viscosity or an enhancement in other fluid properties, for example mitigating the water damage to aluminum-crosslinked gelled oils, which are known to be sensitive to water contamination. The VES may be selected from the group consisting of cationic, anionic, zwitterionic, amphoteric, and nonionic surfactants and combinations of these.
[0016] In embodiments, gelled oils may include other additives and chemicals that are known by those skilled in the art to be commonly used in oilfield applications. These include, but are not necessarily limited to, materials in addition to those mentioned above, such as oxygen scavengers, alcohols, surfactants, co-surfactants, scale inhibitors, corrosion inhibitors, fluid-loss additives, bactericides, organic solvents, and the like. Gelled oils used may be energized or foamed; fluorocarbon surfactants are generally used when foaming of gelled hydrocarbons is required.
[0017] In addition to wellbore cleanout, gelled oils are used as the treatment fluid in hydraulic fracturing, and in sand control treatments such as gravel packing and frac packing They are used as diverters, for example in acid fracturing, where they are pumped in stages alternating with acids or retarded acids such as emulsified acids. They are used as fluid loss control fluids, kill fluids, and lost circulation fluids with or without added solids, including fibers. They are used as oil based drilling fluids and are compatible with fibers, CaCO3, barite, hematite and other weighting agents. They are used over a broad temperature range. They are used to make stable slurries of solid additives. After the use of any fluids, but especially gelled oils, in many of these applications, including remedial treatments, in cases in which solids are left in the wellbore (or in surface or subsurface equipment or lines), it may be appropriate to use a recyclable gelled oil system to remove the solids from the wellbore or elsewhere. Gelled oils are also used outside of wellbores, for example as slugs, or “pigs” for cleaning out coiled tubing, or surface or seafloor pipelines or conduits. Gelled oils are also used outside the oilfield (for example in pharmaceuticals, in cosmetics, for protection of electrical devices and optical cables), and in some applications (for example cleaning equipment after manufacture) recyclable gelled oils may be useful.
[0018] A typical conservative coiled tubing (CT) cleanout with recyclable gelled oil is conducted as follows. The well, for example approximately 1850 m (approximately 6070 feet) deep, is completed with perforated 7.30 cm (2⅞ inch) tubing, and 67 m (220 feet) of solids must be cleaned out. 3.8 Cm (1½) CT is used. The CT is filled with diesel and run in hole without circulating. The well is then opened to flow at about 0.69 MPa (100 psig) above the trunkline pressure; washing the fill is started while advancing the CT and circulating diesel to a depth about 15.2 m (50 feet) below the top of the fill; the tubing is pulled to about 6.1 m (20 feet) above the perforations; and diesel circulation is stopped and the well is shut in for about 30 minutes. The CT is run in without circulating to about 3.05 meters (about 10 feet) above the fill; the well is opened, and about 5675 liters (about 1500 gallons) gelled oil, optionally with the last third foamed, is circulated while moving the CT up and down about every 7.6 m (25 feet) to prevent sand settling and allowing the CT to become stuck. The gelled oil, and optionally foamed gelled oil, steps are repeated until no sand is being recovered over the interval to be cleaned; then diesel, optionally containing pH-raising breaker, is circulated; then the CT is pulled out of the hole while circulating diesel. In a less conservative method, the CT is not reciprocated. In an even more aggressive method, only foamed gelled oil is used. The simplest method is gelled oil only.
[0019] Regarding drilling fluids: conventional oil-based muds (OBM's) give better gauged holes (with less washout) and undergo less reaction with formations and so create less formation damage than water-based muds. Among the limitations of OBM's however are that they require several additives; they undergo settling at high temperatures; they are expensive; and they have handling issues. On the other hand, recyclable gelled oil drilling fluids require fewer additives; are more predictable; are less expensive; have better suspension characteristics; suffer less loss to formations (which is very important) because of their high low-shear viscosities; are compatible with CaCO 3 , barite and hematite and can be weighted as much as required; are compatible with fibers; are compatible with fluid loss additives; and give no solids settling and thus it is easy to achieve heavy (high density) systems.
[0020] Recyclable gelled oils may be used for organic or inorganic scale removal, as perforation fluids, and as gel pigs. Recyclable gelled oil fluid systems can be used to dissolve and remove organic and inorganic deposits, particularly in wellbores, although also in pipelines, tools, and in many other places. They may be used in an analogous manner in industrial cleaning. In this use they may contain various additives such as paraffin or asphaltene inhibitors, and paraffin or asphaltene dispersing agents, and the base oil may advantageously be kerosene, xylene or toluene. The most common targets in the oilfield are asphaltene and paraffin (wax) deposits. Such deposits may also be mixed with inorganic deposits (scales) and in that case the gelled oil dissolver and remover may contain a suitable chelating agent or other scale dissolvers. The viscosity of the systems helps to keep the loose scales in suspension. Because of the high viscosity of the systems they behave like slugs. They will therefore also sweep any debris from a wellbore or pipeline when used to dissolve and remove deposits; or they may be used to sweep out debris even in the absence of organic or organic/inorganic deposits. This system is also used to swap water and other liquid and/or semi solid materials from horizontal or deviated wells and pipelines. Recyclable gelled oil may also be used as a perforation fluid, i.e. the fluid within the casing during perforation. In all these cases, recyclable gelled oils may be returned to the surface, the solids may be removed, and the fluids may be re-gelled and then returned for re-use.
[0021] Fresh (unused) gelled oils may be mixed in the field, for example using batch mixing. In many cases, a fresh gelled oil is pre-made with, for example, diesel, a gelling agent, and a crosslinker at an off-site location, and then shipped to the location for coiled tubing cleanout or other jobs. Continuous mixing on-site or off-site may also be used. When a gelled oil flows back with “fill” in it, base may be added to the gelled oil while blending (or mixing, or agitating) the gelled oil in a pond, or in a container, for example a tank. When the gelled oil breaks, it thins to nearly the viscosity of water, and fill drops to the bottom. The fluid optionally may be allowed to stand for a period of time while the fill settles out. Most of the broken gelled oil (except for the bottom-most portion that contains the fill) is then transferred to a tank or mixer, and acid is added to re-viscosify the gelled oil (both batch and continuous mixing may be used for this step). Optionally, after the viscosity-reduction step, solids may be removed with a shale shaker or similar equipment. In order to maximize the number of cycles that may be performed, if desired, the amount of water added in the pH raising and lowering steps may be minimized by using concentrated or solid pH-adjusting agents, and the viscosity may optionally be measured, and optionally, in any repeat cycles, additional gelling agent or crosslinker (activator) or both, (that may be the same as or different from the initial gelling agent and crosslinker (activator) and if both are added may be added in the same relative concentration as initially used or a different relative concentration than initially used) may be added. This may be particularly important if aluminum-crosslinked phosphate ester gelled oils are contaminated with water during use (for example, if they are contaminated downhole by formation water or by water injected in previous treatments) it may not be worthwhile to reuse it.
[0022] Embodiments can be further understood from the following examples.
EXAMPLE 1
Gelled Oil Crosslinked with the Ferrous (Fe2+) Compound
[0023] The baseline gelled oil (described in U.S. Patent Application Publication No. 20110030953) was prepared with #2 diesel oil, 8 gpt of an alkyl phosphate ester (1 gpt (gallons per thousand gallons)=0.1 vol % (volume percent)) gelling agent, and 16 gpt of a ferrous crosslinker solution. The phosphate ester was a mixture of PO(OR)(OR′)(OR″), PO(OR)(OR′)(OH), and PO(OR)(OH) 2 , where the R, R′, or R″ group was derived from an alcohol and was a hydrocarbon group having from about 1 to about 30 carbon atoms that, for example, was a linear or branched alkyl, alkenyl, aryl, alkylaryl, arylalkyl, cycloalkyl, alkyl ether, aryl ether, alkyl aryl ether, or a mixture of these. The gelled liquid hydrocarbon treatment fluid had a concentration of more than about 250 mg/liter of the alkyl phosphate esters that had a molecular weight of less than about 350. The mixture was gelled in a 1 L Waring blender. The viscosity at room temperature (RT) (about 18 to about 24° C. (about 65 to about 75 ° F.)) was measured with a Fann 35 viscometer (using R1/B1/F1 setting, measured within 10 minutes of the vortex closure in the blender) to be:
[0000] 171 cP at 170/s shear; 70 cP at 511/s shear.
[0024] Then 4 gpt of a 30 wt % NaOH solution was added to the baseline gelled oil while blending. The gelled oil quickly lost its viscosity in the blender, and changed from a gel to a thin liquid. The viscosity of the thin liquid at RT was measured with a Fann 35 to be:
[0000] 15 cP at 170/s shear; 15 cP at 511/s shear (suggesting that it was a Newtonian liquid).
[0025] Then 10.5 gpt HCl (15 wt %) was added to the broken gelled oil (the baseline oil plus the NaOH solution) while blending. The fluid appeared more and more viscous in the blender, and the vortex closed within minutes. The fluid gradually turned into a more viscous gel as the mixing continued, the gel viscosity eventually reaching the maximum (or near maximum) for the composition, which was measured at RT with a Fann 35 to be:
[0000] 162 cP at 170/s shear; 66 cP at 511/s shear.
[0026] The time it would take to recover to at least near maximum viscosity in the field depends at least upon the nature of the components, their concentrations, the mixing energy, and the temperature. Considering that the addition of the NaOH solution and the HCl solution to the baseline gelled oil diluted the baseline gelled oil, the recovery of the fluid viscosity was considered to be nearly 100%.
EXAMPLE 2
Gelled Oil Crosslinked with the Ferric (Fe3+) Compound
[0027] The baseline gelled oil was prepared with #2 diesel, 5 gpt of an alkyl phosphate ester, and 5 gpt of a ferric crosslinker solution, in which the ferric ion is believed to be chelated. The phosphate ester is believed to have been made by contacting phosphorus pentoxide with an alkyl phosphate in the presence of an alcohol, where the alkyl groups are the same or different and have at least four carbon atoms, generally from about 4 to about 16 carbon atoms or mixtures or combinations thereof, where one or more of the carbon atoms can be replaced with a hetero atom selected from oxygen and nitrogen. The phosphate ester product is believed to be a mixture of PO(OR) 3 , PO(OR) 2 (OH) and PO(OR)(OH) 2 , with little or no PO(OR) 3 , where the R group is derived from either the trialkyl phosphate or from the alcohol. The viscosity of the gel at RT was measured with a Fann 35 viscometer to be:
[0000] 105 cP at 170/s shear; 51 cP at 511/s shear.
[0028] Then 4 gpt of a 30 wt % NaOH solution was added to the baseline gelled oil while blending. The gelled oil quickly lost its viscosity in the blender, and changed from a gel to a thin liquid. The viscosity of the thin liquid at RT was measured with a Fann 35 to be:
[0000] 12 cP at 170/s shear; 12 cP at 511/s shear (suggesting that it was a Newtonian liquid).
[0029] Then 10.5 gpt 15 wt % HCl was added to the gelled oil (the baseline gelled oil plus the NaOH solution) while blending. The fluid appeared more and more viscous in the blender, and the vortex closed within minutes. The fluid gradually turned into a more viscous gel as the mixing continued, the gel viscosity eventually reaching the maximum (or near maximum) for the composition, which was measured at RT with a Fann 35 to be:
[0000] 93 cP at 170/s shear; 46 cP at 511/s shear.
[0030] Considering that the addition of the NaOH solution and the HCl solution to the baseline gelled oil diluted the baseline gelled oil, the recovery of the fluid viscosity was considered to be nearly 100%.
EXAMPLE 3
Gelled Oil Crosslinked with the Aluminum Compound
[0031] The baseline gelled oil was prepared with #2 diesel, 6 gpt of a phosphate ester solution, and 1.8 gpt of an aluminum crosslinker solution. The phosphate ester solution was a mixture of 80% of a mixture of ethyl, octyl and decyl esters of phosphoric acid and 20% of an aromatic hydrocarbon solvent. The aluminum crosslinker solution was a mixture of about 24% 2-ethylhexan-1-ol and 59% aluminum triisopropanolate and 17% diesel oil. All amounts given are for as-received materials. The viscosity of the gel at RT was measured with a Fann 35 viscometer to be:
[0000] 174 cP at 170/s shear; 86 cP at 511/s shear.
[0032] Then 4 gpt of 30 wt % NaOH solution was added to the baseline gelled oil while blending. The gelled oil quickly lost its viscosity in the blender, and changed from a thick gel to a thin liquid. 10.5 gpt 15 wt % HCl was then added to the gelled oil (the baseline gelled oil plus the NaOH solution) while blending. The fluid gradually turned into a more viscous gel as the mixing continued, the gel viscosity eventually reaching the maximum (or near maximum) for the composition, which was measured at RT with a Fann 35 to be:
[0000] 78 cP at 170/s shear; 42 cP at 511/s shear.
[0033] Gelled oils crosslinked with aluminum compounds are often sensitive to water contamination, which might be the reason why the gelled oil in this example lost a large percentage of its viscosity. However, this gelled oil may still be reusable as it does retain significant portion of its initial viscosity. If more concentrated or solid NaOH and more concentrated HCl had been used, the impact of the water would have been reduced, and the viscosity of the recycled gelled oil would have been higher.
[0034] Any element in the examples may be replaced by any one of numerous equivalent alternatives, only some of which are disclosed in the specification. 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 the concepts described herein. Accordingly, all such modifications are intended to be included within the scope of this disclosure as defined in the following claims. 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. | A method for treating a wellbore or a subterranean formation penetrated by a wellbore includes preparing a gelled oil at the surface, introducing the gelled oil into the wellbore, recovering the gelled oil at the surface, adding a base to the gelled oil to reduce the viscosity, allowing entrained solids to settle out, adding an acid to increase the viscosity, and re-injecting the gelled oil. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to an expansion joint for modular flooring. More particularly, the invention relates to the use of a slidable member which is interspersed between tiles of plastic modular flooring, which is adapted to permit relative movement of subsections of the modular flooring during installation.
2. Description of the Prior Art
Modular flooring of various designs has been utilized for a significant period of time to provide a temporary walking or other rigid surface in areas where permanent flooring is either not necessary or prohibitively expensive. More particularly, modular flooring is primarily utilized in commercial settings where a floor is temporarily needed, such as on a grass or artificial turf surface as well as in industrial or construction areas. With respect to industrial or construction areas, temporary flooring may be utilized to provide walkways, driveways, parking areas or other rigid surfaces for the transport of materials, vehicles, storage or mounting of equipment, or simply as a walking or standing surface for people. The modular nature of such flooring is utilized to adapt the flooring to the particular topographic or geographic needs of the particular site and to also allow for the efficient storage and transport of the modular flooring. In addition, the use of relatively small modular floor tiles permits repairs and disposal of broken floor sections with relative ease.
In operation, the selection of the particular floor tile and its characteristics are primarily based upon the amount of load expected to be exerted on the modular flooring system, as well as the relative support characteristics of the underlying substrate be it concrete, artificial turf, grass, dirt, or the like. Once the particular floor tile is selected, a number of modular tiles typically having some type of interlock mechanism are applied to the surface and are generally laid in a sequential pattern, permitting the selective interlock of the various tiles and the placement of those tiles in a preplanned topographic design intended to permit the movement of materials, people, vehicles or the storage of the same in appropriate locations. The modular floor tiles are themselves typically constructed of plastic or other polymeric materials which permit relatively high-strength sections having relatively low weight, providing ease of storage and portability. One particular shortcoming of plastic and polymeric materials is the coefficient of thermal expansion, which is relatively high in practice. Changes in temperature of the underlying substrate material, as well as the ambient air proximate to the modular floor system cause relatively significant changes in dimensionality of the floor tiles. While the dimensional changes in each individual tile are relatively small, over a large area with hundreds, perhaps thousands, of interlocked tiles, the cumulative expansion or contraction of the entire flooring system causes significant problems with respect to maintenance of the floor, as well as the safety of the users.
In practice, this expansion of the modular flooring system causes buckling, shifting and cracking of the floor tiles, as well as providing a tripping hazard for persons walking on the floor and potentially causing dangerous conditions which could cause vehicles to be diverted from their intended course over the surface of the modular floor.
Other limitations of the modular flooring system include the requirement that the floor be laid sequentially in order to ensure the appropriate alignment and interlocking of the modular tiles. In practice, this means that a tile floor must be laid from one location and expanding outwardly from that location on an interlocking basis and cannot be laid in discontinuance sections. Furthermore, the alignment and location of each tile is very important because small deviations from the preplanned alignment of the tiles over the course of longer distances will result in a floor being significantly displaced from its preplanned location. This results in significant delays and costs associated with picking up and relaying the various floor tiles once the misalignment has been discovery after a significant number of tiles have been laid.
There remains a need, therefore, in the art of modular flooring, for an adjustable or displaceable tile which may be inserted at various locations in a modular floor system to absorb the expansion of the floor tiles in atmospheric conditions which cause expansion and contraction of the modular floor or subsections thereof. Additionally, there remains a need in the art for an adjustable tile which may be inserted in order to maintain the alignment and appropriate location of sections for the entirety of the modular floor over its length.
SUMMARY OF THE INVENTION
A modular floor expansion joint is disclosed which provides both a means for absorbing the expansion of adjoining floor tiles and permitting the various expanding or contracting sections of the modular floor to remain flat on the substrate, as well as to permit a minimal amount of misalignment in the application of the floor tiles to a substrate by providing an adjustment means for subsections of the floor. In practice, this permits the insertion of the expansion joint tiles at locations where a misalignment has occurred and been discovered. Once a significant portion of the modular floor has been laid, the adjustability of the modular floor tile expansion joint permits the realignment of neighboring sections of adjoined modular floor tiles to the preplanned topographic location. The expansion joint also prevents the floor to be laid in discontinuous sections which may be moderately misaligned and joined by the adjustable expansion tile.
The expansion joint floor tile is provided as a generally slidably, adjustable multi-section tile and is equipped with appropriately sized and shaped interlocking devices such that it may be mounted within a floor tile matrix as any location, replacing one or a series of modular floor tiles without disrupting the alignment pattern of such a modular floor tile system. The slidable multi-part tile is generally adapted to expand or contract in one dimension, but may be laid in an aligned pattern, such that the axes of expansion are aligned linearly or in a parallel fashion, or may be laid in a parquet style to permit multi-dimensional expansion or contraction of the floor as well.
The multi-section expansion joint is generally provided in the preferred embodiment with two interlocking sections, one of which slides and is located within a locating sleeve of the other. An indented or undercut portion of a first member is adapted to be inserted and be slidably displaceable within the sleeve provided in the second member. The two members are adapted to be either temporarily or permanently joined through any particular means well-known to those skilled in the art in the preferred embodiments. A protrusion is provided on one member to be interfaced with a slot on the second member, such that the protrusion may be inserted into the slot and then laterally displaced along the longitudinal axis of the slot. A variety of locating means may be utilized to both use the insertion of the members together, as well as to maintain the geometric alignment of the two members during the sliding process in an axial fashion.
In order to maintain the compressive strength of the floor tile system, a series of support webs, or other reinforcing means may be applied to the expansion joint, such that it matches the adjoining floor tiles in height and other critical dimensions, as well as its ability to support the intended load. Lastly, for both cosmetic and functional reasons, the exterior surface of the floor tile may be provided with both decorative embellishments, as well as various ventilation or other functional surface features to permit or prevent the passage of moisture facilitating the passage of persons and vehicles thereover. This is utilized to increase the frictional characteristics of the top surface so that a slippery condition is not provided on the top surface when mounted within the modular flooring system.
These and other advantages of the expansion joint provided herein will be more fully understood with reference to the appended drawings and the description of the preferred embodiments herein.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a top plan view of a first embodiment of a modular flooring system, including both prior art floor tiles and a first embodiment of the expansion joint tile.
FIG. 2 is a top plan view of a second embodiment of a modular flooring system, including both prior art floor tiles and a second embodiment of the expansion joint tile.
FIG. 3 is a top plan view of the embodiment illustrated in FIG. 1 with the expansion joint in an extended orientation.
FIG. 4 is a top plan view of the embodiment illustrated in FIG. 2 with the expansion joint in an extended orientation.
FIG. 5 is an isometric exploded view of a first embodiment of the expansion joint as seen from the top.
FIG. 6 is an isometric exploded view of a first embodiment of the expansion joint as seen from the bottom.
FIG. 7 is an isometric view of the top of the second embodiment of the expansion joint in the closed position.
FIG. 8 is an isometric view of the second embodiment of expansion joint as viewed from the bottom in the open position.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG. 1 , a matrix of modular floor tiles is illustrated having a number of component parts. A first embodiment is depicted in FIG. 1 while a second embodiment is depicted in FIG. 2 . Referring now to FIGS. 1 and 2 , modular floor tiles of the prior art are identified as floor tiles 1 . The first embodiment being identified as embodiment 1 a and the second embodiment being 1 b . References herein to elements common to both embodiments will identify those same elements by reference numeral where the embodiments differ. The further identifiers, a and b will be used respectively, modular floor tiles 1 are provided in an interlocking matrix 10 which extends in two dimensions in accordance with a preset topographic plan. As discussed previously, the topographic plan is typically directed towards the conveyance or support of equipment, vehicles, personnel and the like and is adapted to conform to the topographic or geographic features of the substrate surface, such as grass, dirt, artificial turf or the like, modular floor tiles 1 are typically constructed of plastic material and are preferably polypropylene, polyethylene, polystyrene, acrylonitrile butadiene styrene, and polyvinylchloride. Differences between the first and second embodiments, as well as other embodiments not illustrated herein, but within the scope of knowledge of one skilled in the art, would include changes in dimensionality, including height, width and length, as well as surface features. Although not specifically illustrated, the invention contemplates the use of three-dimensional surface features to reduce slippage as well as ventilation holes 25 illustrated in FIG. 1 of the first embodiment. Other applications may include three-dimensional surface features for the conveyance of moisture, as well as for decorative purposes. One significant feature of modular floor tile 1 when assembled into a matrix 10 is the desire to reduce any misalignment or unintentional three-dimensional surface changes in the top surface 27 of the floor tiles. Any height misalignment or departure of the floor tile from uniform engagement with the substrate may result in an unsafe condition presented by improper interlocking of modular floor tiles 1 or buckling of the entirety or portions of the matrix 10 surface causing an uneven walking or vehicular traffic surface.
In application, modular floor tiles 1 are typically provided with a series of locking tabs 15 , which extend outwardly from the perimeter of each tile. In accordance with the specific design features of each embodiment, the locking tabs may be of any size or shape appropriate to support the weight and load requirements of the tile. Furthermore, the number of distribution of the locking tabs 15 are determined by the physical conditions of the likely substrate, as well as the load requirements mentioned previously. Locking receptacles 20 are also located on the perimeter of each of the modular floor tiles 1 for receiving and restraining locking tabs 15 and are disposed geometrically in accordance with the corresponding location of locking tabs 15 on adjacent floor tiles 1 . It will thus be appreciated that the sequential application of modular floor tiles 1 will include the serial interlocking of adjacent floor tiles in a matter to extend matrix 10 in two dimensions. In accordance with the preferred embodiments herein, an expansion tile 30 is provided, which may be interspersed at various frequencies within matrix 10 as a substitute for modular floor tiles 1 . Expansion tiles 30 may be aligned linearly on an axial geometry or as illustrated in FIGS. 1 and 2 . The linear geometry in which the adjacent expansion tiles 30 are adapted and aligned, such that the direction of their expandability is similarly aligned to provide an extended section of expandability within matrix 10 , as will be more fully understood with references to FIGS. 3 and 4 . As illustrated in FIGS. 1 and 2 , expansion tiles 30 are shown in a closed position, which is one of three likely positions provided for expansion tiles 30 being fully closed, fully open and then intermediate position. The mounting and insertion of expansion tiles 30 is dependent upon the anticipated changes in weather conditions, as well as changes in substrate and the likely need for adapting matrix 10 during the installation period of modular floor tiles 1 . It will be appreciated by those skilled in the art that to the extent that the likely temperature change of the ambient air and adjacent surface or substrate is likely to increase then the expansion tile 30 would be laid in an open position or an intermediate position whereas, if it is likely that the temperature will substantially decrease, then the expansion tile 30 would be laid in the closed position, or an intermediate position, as it is well-known to those skilled in the art that the plastic material expands with increasing temperature. The insertion of expansion tiles 30 are specifically intended to permit the relative movement of sections of matrix 10 relative to each other during the expansion and contraction of modular floor tiles 1 within matrix 10 , without creating any surface irregularities or misalignments of modular floor tiles 1 within matrix 10 . Furthermore, it is intended that the adjustability of expansion tiles 30 will reduce damage to modular floor tiles 1 , which might occur as a consequence of the relative rigidity of modular floor tiles 1 within respect to the increasing or decreasing lateral forces on the tile within the matrix because of changing temperatures.
Referring now to FIGS. 3 and 4 , expansion tile 30 is shown in an extended orientation or open orientation which pen-nits the exposure of the interior of expansion tile 30 . Expansion tile 30 is provided with a top surface 35 and the expansion joint itself is provided with expansion joint top surface 40 , as will be more fully illustrated with respect to FIGS. 5 , 6 , 7 and 8 . The design of expansion tile 30 is specifically intended to provide a relatively flat surface within the tolerances necessary to reduce any hazard of tripping or other negative consequences of an uneven floor surface. Even in the extended or open mode identified in FIGS. 3 and 4 , expansion tile 30 provides a relatively flat surface over the extent of matrix 10 with significant minimization of surface irregularities or discontinuous portions.
Referring now to FIGS. 5 and 6 , the specific features unique to the first embodiment will be illustrated. However, unless specifically identified as a separate features, corresponding parts having identical reference numerals between the first and second embodiments illustrated in FIGS. 5 and 6 , and 7 and 8 , respectively, shall be considered applicable to both embodiments. Referring now particularly to FIGS. 5 and 6 , expansion tile 30 a is provided with an expansion tile upper surface 35 a , locking tabs 15 are provided in a generally “T” shaped orientation, having a roughly cylindrical members extending outwardly therefrom for the rotational insert in corresponding locking receptacles 20 , where locking tab 15 may be tipped in at an angle to the substrate surface and inserted within locking receptacle 20 and rotated angularly about locking tab 15 to permit the secure interconnection between adjacent expansion tiles 30 or separate ones of expansion tiles 30 and modular floor tiles 1 .
Expansion tile 30 a is generally provided with two separable subsections, being the support section 53 and the sleeve section 54 . In general operations, support section 53 is inserted into and slidably engages sleeve section 54 . Support section 53 is provided with an expansion joint support 50 in the general format of an extending armature which is partially defined by undercut track 70 and expansion joint top surface 40 a . The combination of these two elements form expansion joint support 50 , which is an adaption for slidable engagement and insertion into sleeve section 54 . Expansion joint support 50 is provided with expansion slots 45 on expansion joint top surface thereof, which are adapted to receive and slidably restrain locking pins 85 , as will be further discussed with respect to FIG. 6 . A flexible spring 65 is provided at the distal end of expansion joint support 50 for engagement with an inner surface of sleeve section 54 and which biases expansion tile 30 a from a closed position to an intermediate open position.
Sleeve section 54 is provided with expansion joint sleeve 55 , which is defined as an overhanging section of sleeve section 54 , adapted to receive expansion joint support 50 within expansion joint receiver 60 , defining an open space into which expansion joint support 50 is inserted and received. Essentially, expansion joint receiver 60 is formed by an overhanging section of expansion tile top surface 35 a and the side walls of sleeve section 54 . Referring now to FIG. 6 , the undersurface of expansion tile 30 a is illustrated, having a series of support web members 80 which may be arranged and disposed in any particular pattern, which provides dimensional and load support for top surface 35 a . The bottom surface 75 of expansion tile 30 a is formed as the underside of the plastic sheeting material forming top surface 35 a and ventilation holes 25 extend therethrough to provide fluid and/or air communication between expansion joint bottom surface 75 and top surface 35 a . Expansion joint sleeve bottom surface 76 is provided with at least one, and preferably a series of locking pins 85 , which are typically extending outwardly from expansion joint sleeve bottom surface 76 and are provided with any type of restraining geometry known to those skilled in the art and most preferably at least one hook interface to be inserted within slots 45 of support section 53 for a semi-permanent engagement. It is specifically intended that having been inserted in slots 45 , locking pins 85 are either not removable or removable only with intent and some degree of difficulty. As assembled, expansion tile 35 a permits the slidable engagement of support section 53 and sleeve section 54 through the displacement of locking pins 85 within slots 45 and the extremes of such travel are defined by the length of slot 45 and the number and location of locking pins 85 .
Referring flow to FIGS. 7 and 8 , the second embodiment is illustrative of expansion tile 30 b having a top surface 35 b and an insert section 57 and receiver section 56 . While not functionally identical to support section 53 and sleeve section 54 , insert section 57 and receiver section 56 perform roughly analogous functions. As with the first embodiment, expansion joint bottom surface 75 is provided with at least one or a series of support webs 80 , which provides structural support for top surface 35 b . Insert section 57 is generally provided with an expansion joint 50 , which is formed primarily by undercut track 70 and is adapted to be inserted in slidably received by expansion joint receiver 60 within receiver section 56 . A series of expansion slots 45 are provided for receiving and restraining locking pins 85 , which are affixed to the bottom surface 75 of receiver section 56 . As with the first embodiment, these locking pins may be provided with any particular arrangement of protrusions to permit the engagement and restraint of locking pins 85 within slots 45 . The second embodiment, however, provides an insertion hole 62 within expansion slot 45 for the easy insertion and removal of locking pins 85 within expansion slot 45 . As with the first embodiment, the locking pins 85 define the length and extent of travel of the slidable engagement between receiver section 56 and insert section 57 . Additional lateral support for the sliding engagement of receiver section 56 and insert section 57 is provided by locating slots 90 provided in insert section 57 and locating tabs 95 provided on the bottom surface 75 of receiver section 56 . Locating tabs 95 are arranged perpendicularly to bottom surface 75 and are adapted for the slidable insertion within locating slots 90 .
Finally, one preferred embodiment of the invention has been described hereinabove and those of ordinary skill in the art will recognize that this embodiment may be modified and altered without departing from the central spirit and scope of the invention. Thus, the embodiment described hereinabove is to be considered in all respects as illustrative and not restrictive. The scope of the invention being indicated by the appended claims rather than the foregoing descriptions and all changes which come within the meaning and range of equivalency of the claims are intended to be embraced herein. | An expansion joint for a modular flooring system in disclosed, which includes the slidable engagement of two subsections of the expansion joint. The expansion joint is sized such that it is equivalent in overall dimension to the intended adjacent modular floor tiles of which it will form a part within a matrix of such interlocked modular floor tiles. The expansion joint is provided with at least one slot on one module, corresponding to at least one locking pin on the other module. The slot receives and restrains the locking pin and permits the slidable engagement along the longitudinal axes thereof. | 4 |
BACKGROUND OF THE INVENTION
[0001] The present invention relates to a process for the preparation of a 4,5-diamino shikimic acid derivative of formula
and pharmaceutically acceptable addition salts thereof
wherein
R 1 , R 1′ are independent of each other H or alkyl, R 2 is an alkyl and R 3 , R 4 are independent of each other H or an alkanoyl, with the proviso that not both R 3 and R 4 are H.
[0005] 4,5-diamino shikimic acid derivatives of formula I, especially the (3R,4R,5S)-5-amino-4-acetylamino-3-(1-ethyl-propoxy)-cyclohex-1-ene-carboxylic acid ethyl ester and its pharmaceutically acceptable additional salts are potent inhibitors of viral neuramimidase (J. C. Rohloffet al., J. Org. Chem. 63, 1998, 4545-4550; WO 98/07685).
[0006] The problem at the root of the present invention is to provide a new process for preparing 4,5-diamino shikimic acid derivatives in good quality and yield from a easily obtainable starting material, 5-amino-shikimic acid. 5-amino-shikimic acid can be easily obtained from biotech processes, e.g. genetic engineering, fermentation (Jiantao Guo and J. W. Frost, Organic Letters, Vol. 6, No. 10, 2004, 1585-1588).
SUMMARY OF THE INVENTION
[0007] The problem is solved, according to the present invention, by a process for preparing the compounds of formula I as show in scheme 1:
[0008] This new process has the advantage that it comprises less steps to reach 4,5-diamino shikimic acid derivatives of formula I comparing with the process known from the art (J. C. Rohloffet al., J. Org. Chem. 63, 1998, 4545-4550; WO 98/07685).
DETAILED DESCRIPTION OF THE INVENTION
[0009] The novel process of the present invention comprises
[0000] in step a):
[0000]
esterifying 5-amino shikimic acid of formula
with R 2 OH to form a compound of formula
in step b):
reacting compound of formula III with an alkanone to form a ketal of formula
wherein R 1 , R 1′ and R 2 are as defined above,
in step c):
effecting reductive ketal opening to form a compound of formula
wherein R 1 , R 1′ and R 2 are as defined above,
in step d):
transforming the aminoalcohol of formula V into a diamino compound of formula
wherein R 1 , R 1′ and R 2 are as defined above, R 5 and R 6 , independently of each other, are H or an amino protecting group, with the proviso that not both R 5 and R 6 are H,
in step e):
acylating the free amino function of compound of formula VI to form an acylated compound of formula
wherein R 1 , R 1 ′, R 2 , R 3 , R 4 , R 5 and R 6 are as defined above,
and in step f):
reducing the compound of formula VII to compound of formula I and, if desired, forming a pharmaceutically acceptable addition salt.
[0016] The term alkyl has the meaning of a straight chained or branched alkyl group of 1 to 20 C-atoms, expediently of 1 to 12 C-atoms. Examples of such alkyl groups are methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, tert. butyl, pentyl and its isomers, hexyl and its isomers, heptyl and its isomers, octyl and its isomers, nonyl and its isomers, decyl and its isomers, undecyl and its isomers and dodecyl and its isomers.
[0017] This alkyl group can be substituted with one or more substituents as defined in e.g. WO 98/07685. Suitable substituents are C 1-6 -alkyl (as defined above), C 1-6 -alkenyl, C 3-6 -cycloalkyl, hydroxy, C 1-6 -alkoxy, C 1-6 -alkoxycarbonyl, F, Cl, Br and I.
[0018] The term alkyl in R 1 , R 1′ has the meaning of a straight chained or branched alkyl group of 1 to 20 C-atoms, expediently of 1 to 12 C-atoms.
[0019] Preferred meaning for R 1 is ethyl, for R 1′ is ethyl.
[0020] R 2 is a straight chained or branched alkyl group of 1 to 12 C-atoms, expediently of 1 to 6 C-atoms as exemplified above.
[0021] Preferred meaning for R 2 is ethyl.
[0022] R 3 and R 4 have the meaning of alkanoyl groups, more preferably C 1-6 -alkanoyl such as hexanoyl, pentanoyl, butanoyl (butyryl), propanoyl (propionyl), ethanoyl (acetyl) and methanoyl (formyl).
[0023] Preferred meaning for R 3 is acetyl and for R 4 is H.
[0024] The term amino protecting group refers to any protecting group conventionally used and known in the art. They are described e.g. in “Protective Groups in Organic Chemistry”, Theodora W. Greene et al., John Wiley & Sons Inc., New York, 1991, p. 315-385. Suitable amino protecting groups are also given in e.g. the WO 98/07685.
[0025] Preferred amino protecting groups for R 5 and R 6 are straight chained or branched alkenyl of 2 to 6 C-atoms, optionally substituted benzyl or tri-substituted silyl methyl or heterocyclyl methyl.
[0026] Straight chained or branched alkenyl of 2 to 6 C-atoms preferably is allyl or an analog thereof such as allyl or an allyl group which is substituted on the α-, β- or γ-carbon by one lower alkyl, lower alkenyl, lower alkynyl or aryl group. Suitable examples are e.g. 2-methylallyl, 3,3-dimethylallyl, 2-phenylallyl, or 3-methylallyl.
[0027] Preferred meaning for R 5 and R 6 are straight chained or branched alkenyl of 1 to 6 C-atoms group. Suitable examples are e.g. allyl, diallyl or 2-methylallyl.
[0028] Most preferred meaning for R 5 is allyl, for R 6 is H.
[0029] The term “pharmaceutically acceptable acid addition salts” embraces salts with inorganic and organic acids, such as hydrochloric acid, hydrobromic acid, nitric acid, sulfuric acid, phosphoric acid, citric acid, formic acid, fumaric acid, maleic acid, acetic acid, succinic acid, tartaric acid, methanesulfonic acid, p-toluenesulfonic acid, benzenesulfonic acid and the like.
[0030] The salt formation is effected with methods which are known per se and which are familiar to any person skilled in the art. Not only salts with inorganic acids, but also salts with organic acids come into consideration. Hydrochlorides, hydrobromides, sulfates, nitrates, citrates, acetates, maleates, succinates, methan-sulfonates, p-toluenesulfonates and the like are examples of such salts.
[0031] Preferred pharmaceutically acceptable acid addition salt is the 1:1 salt with phosphoric acid which can be formed preferably in ethanolic solution at a temperature of −20° C. to 60° C.
[0000] Step a)
[0032] Step a) comprises esterifying (3R,4S,5R)-5-amino-3,4-dihydroxy-cyclohex-1-enecarboxylic acid of formula II with an alcohol of formula R 2 OH.
[0033] Typically, the reaction is performed in an alcohol, preferably ethanol in the presence of a strong acid, such as hydrogen chloride in ethanol, hydrochloric acid, hydrobromic acid, sulfuric acid, phosphoric acid, methanesulfonic acid, p-toluenesulfonic acid, benzensulfonic acid and the like, preferably hydrogen chloride in ethanol or methanesulfonic acid.
[0034] The reaction temperature mainly depends on the alcohol used, as a rule lies in the range of 60° C. to 150° C., preferably 70° C. to 100° C.
[0035] The reaction is as a rule finished after 1 to 10 hours, preferably 3 to 7 hours.
[0000] Step b)
[0036] Step b) comprises reacting compound of formula III with an alkanone.
[0037] Typically the reaction is performed in a suspension of compound of formula III, an alkanone, such as a C 1 -C 12 -alkanone, preferably 3-pentanon, and a strong acid, such as hydrochloric acid, hydrobromic acid, sulfuric acid, phosphoric acid, benzenesulfonic acid, methanesulfonic acid, p-toluenesulfonic acid and the like, preferably methanesulfonic acid.
[0038] The reaction temperature is typically in the range of 50° C. to 150° C., preferably 80° C. to 120° C.
[0039] The reaction time is as a rule 1 to 5 hours, preferably 1.5 to 2.5 hours.
[0040] Thereafter work up of the reaction mixture can happen by applying methods known to those skilled in the art. Expediently, the reaction mixture is diluted with an aprotic solvent, such as tetrahydrofuran, diisopropylether, tert.-butyl methyl ether, acetonitrile, toluene, ethyl acetate or a mixture thereof, preferably ethyl acetate and extracted with an aqueous basic solution, such as aqueous ammonium hydroxide solution, aqueous sodium carbonate solution, aqueous sodium hydrogen carbonate solution, aqueous potassium hydrogenphosphate, aqueous sodium hydrogenphosphate or aqueous amine solution, e.g. aqueous methylamine solution or aqueous ethylamine solution, preferably aqueous sodium hydrogen carbonate solution.
[0000] Step c)
[0041] The reaction of step c) is typically performed in an inert organic solvent, such as trichloromethane or dichloromethane.
[0042] A ketal opening reagent, such as borane-methyl sulfide complex/trimethylsilyltrifluoromethanesulfonate or triethylsilane/titanium tetrachloride is added to the reaction mixture at a temperature range of −70° C. to −20° C.
[0043] The reaction temperature is typically at a temperature range of −70° C. to −20° C., preferably −25° C. to −20° C.
[0044] The reaction is as a rule finished after 10 to 30 hours, preferably 24 hours.
[0045] Thereafter work up of the reaction mixture can happen by applying methods known to those skilled in the art. Expediently, the reaction mixture is washed with an aqueous basic solution, such as aqueous ammonium hydroxide solution, aqueous sodium carbonate solution, aqueous sodium hydrogen carbonate solution aqueous potassium hydrogenphosphate, aqueous sodium hydrogenphosphate or an aqueous amine solution, e.g. aqueous methylamine solution or aqueous ethylamine solution, preferably an aqueous ammonium hydroxide solution and extracted with organic solvent, such as tetrahydrofuran, diisopropylether, tert.-butyl methyl ether, acetonitrile, toluene, ethyl acetate or a mixture thereof, preferably ethyl acetate.
[0000] Step d)
[0046] step d) comprises the steps,
d1) introducing an amino group substituent into the 2-aminoalcohol of formula V obtained in step c), d2) transforming the hydroxy group into a leaving group, and d3) splitting off the substituent of the amino group and transforming the reaction product using an amine of formula R 5 NHR 6 , wherein R 5 and R 6 are as above into a 1,2-diamino compound of formula VI.
Step d1)
[0050] Particularly interesting is the conversion of the amino group with a carbonyl group containing compound to form an imine, a so called “Schiff base”.
[0051] Formation of a Schiff base is the preferred method for the conversion of the free amino group into the substituted amino group of the 2-aminoalcohol of formula V.
[0052] Carbonyl compounds suitable to form a Schiff base are either aldehydes or ketones. Both the aldehydes and the ketones can be aliphatic, alicyclic or aromatic, preferably aromatic.
[0053] Examples of suitable aliphatic aldehydes are propionaldehyde, 2-methylpentenal, 2-ethylbutyraldehyde, pivaldehyde, ethyl glyoxylate and chloral. An example of an alicyclic aldehyde is cyclopropan carbaldehyde. Examples of suitable aromatic aldehydes are furfural, 2-pyridinecarboxylaldehyde, 4-methoxybenzaldehyde, 3-nitrobenzaldehyde, a benzaldehyde sulfonate, a furfural sulfonate, and benzaldehyde. A particularly interesting aromatic aldehyde is benzaldehyde.
[0054] Examples of suitable aliphatic ketones are 1,1-dimethoxyacetone and 1,1-diethoxyacetone. Examples of suitable alicyclic ketones are cyclopentanone, cyclohexanone, cycloheptanone, 2-ethyl cyclohexanone and 2-methyl-cyclopentanone. An example of an aromatic ketone is acetophenone.
[0055] Preferred carbonyl containing compound is benzaldehyde.
[0056] The carbonyl containing compound is expediently used in an amount of 1.0 to 1.50, preferably 1.10 to 1.40 equivalents relating to the 2-aminoalcohol of formula IV.
[0057] Formation of the Schiff base is advantageously performed in a protic or aprotic solvent, preferably in an aprotic solvent.
[0058] Suitable aprotic solvents are for example tetrahydrofuran, dioxane, tert.-butyl methyl ether, diisopropylether, isopropylacetate, ethylacetate, methylacetate, acetonitrile, benzene, toluene, pyridine, methylene chloride, dimethylformamide, N-methylformamide and dimethylsulfoxide.
[0059] A preferred aprotic solvent is tert.-butyl methyl ether.
[0060] The water formed is usually removed by azeotropic distillation.
[0061] Formation of the Schiff base is advantageously carried out at temperatures between 30° C. and 180° C., preferably between 60° C. and 140° C.
[0000] Step d2)
[0062] Step d2) comprises transforming the hydroxy group into a leaving group, thereby forming an O-substituted 2-aminoalcohol.
[0063] Compounds and methods for effecting this transformation are well known in the art and described e.g. in “Advanced Organic Chemistry”, ed. March J., John Wiley & Sons, New York, 1992, 353-357.
[0064] It was found that the hydroxy group is preferably transformed into a sulfonic acid ester.
[0065] Agents commonly used for producing sulfonic acid esters e.g. are the halogenides or the anhydrides of the following sulfonic acids: methane sulfonic acid, p-toluenesulfonic acid, benzensulfonic acid, p-nitrobenzenesulfonic acid, p-bromobenzenesulfonic acid or trifluoromethanesulfonic acid.
[0066] Preferred sulfonylating agent is a halogenide or the anhydride of methane sulfonic acid such as methane sulfonylchloride.
[0067] The sulfonylating agent is expediently added in an amount of 1.0 to 2.0 equivalents relating to one equivalent of the 2-aminoalcohol of formula V.
[0068] Usually the reaction in step d2) takes place in an inert solvent, preferably in the same solvent which has been used in the previous step d1) and at a reaction temperature of −20° C. to 100° C.
[0000] Step d3)
[0069] Step d3) comprises splitting off the substituent of the amino group and transforming the reaction product using an amine of formula R 5 NHR 6 , wherein R 5 and R 6 are as above into 1,2-diamino compound of formula V.
[0070] The course of the reaction in step d3) and the respective reaction conditions mainly depend on the kind of protection of the amino group in step d2).
[0071] Having a Schiff base the transformation is directly effected with the amine of formula R 5 NHR 6 , whereby having an acyl group, prior to the transformation with the amine of formula R 5 NHR 6 a deacylation treatment has to take place first.
[0072] The term “acyl” means alkanoyl, preferably lower alkanoyl, alkoxy-carbonyl, preferably lower alkoxy-carbonyl, aryloxy-carbonyl or aroyl such as benzoyl.
[0073] In case of a Schiff base, the amine of formula R 5 NHR 6 is used in an amount of at least two equivalents, preferably of 2.0 to 5.0, more preferably of 2.5 to 4.0 equivalents relating to one equivalent of the 2-aminoalcohol of formula V.
[0074] The solvent used in this reaction step d3) is as a rule the same as of the previous step d2). Accordingly protic or aprotic solvents, preferably aprotic solvents, such as for example tetrahydrofuran, dioxane, tert.-butyl methyl ether, diisopropylether, isopropylacetate, ethylacetate, methylacetate, acetonitrile, benzene, toluene, pyridine, methylene chloride, dimethylformamide, N-methylformamide and dimethylsulfoxide can be used. A preferred solvent is tert.-butyl methyl ether.
[0075] In case of a Schiff base the conversion is advantageously carried out at a temperature of 60° C. to 170° C., preferably of 90° C. to 130° C. and applying normal pressure to 10 bars.
[0076] In case the substituted amino group is acyl, prior to the treatment with the amine of formula R 5 NHR 6 deacylation has to take place as mentioned above.
[0077] Deacylation can easily be effected under acidic conditions e.g. using sulfuric acid, methanesulfonic acid or p-toluenesulfonic acid in an alcohol, such as methanol, ethanol or isopropanol, preferably ethanol.
[0078] Thereby the respective sulfonate or sulfate salt of the O-substituted 2-aminoalcohol is formed.
[0079] The amine of formula R 5 NHR 6 used in this step is allylamine, diallylamine, benzylamine, dibenzylamine or trimethylsilylamine.
[0080] The amine of the formula R 5 NHR 6 is then suitably used in an amount of 1.0 to 5.0 equivalents, preferably of 2.0 to 4.0 equivalents relating to one equivalent of the 2-aminoalcohol of formula V.
[0081] The choice of solvents is about the same as for the conversion of the Schiff base, preferably ethyl acetate or tert.-butyl methyl ether.
[0082] The reaction temperature is chosen between 60° C. and 170° C., preferably between 90° C. and 130° C. and the pressure is selected between normal pressure and 10 bar.
[0083] When operating with a Schiff base step d) thus can efficiently be performed in a one pot synthesis without isolating the intermediates.
[0000] Step e)
[0084] Step e) comprises the acylation of the free amino function in position 1 to form an acylated 1,2-diamino compound of formula VII.
[0085] Acylation can be effected under strong acidic conditions by using acylating agents known to the skilled in the art. Acylating agent can be an aliphatic or aromatic carboxylic acid, or an activated derivative thereof, such as an acyl halide, a carboxylic acid ester or a carboxylic acid anhydride. Suitable acylating agent preferably is an acetylating agent such as acetylchloride, trifluoracteylchloride or acetic anhydride. Suitable aromatic acylating agent is benzoylchloride. Strong acids suitably used e.g. are mixtures of methane sulfonic acid and acetic acid or sulfuric acid and acetic acid.
[0086] Acylation however can also take place under non acidic conditions using e.g. N-acetyl imidazole or N-acetyl-N-methoxy acetamide.
[0087] Preferably however the acylation takes place under acidic conditions using a mixture of 0.5 to 2.0 equivalents of acetic anhydride, 0 to 15.0 equivalents of acetic acid and 0 to 2.0 equivalents of methanesulfonic acid in ethyl acetate.
[0088] An inert solvent such as tert.-butyl methyl ether may be added, it is however also possible to run the reaction without addition of any solvent.
[0089] The temperature is as a rule chosen in the range of −20° C. to 100° C.
[0000] Step f)
[0090] Step f) comprises releasing the amino group and, if necessary, further transforming the resulting 1,2-diamino compound of formula I into a pharmaceutically acceptable addition salt.
[0091] Isomerization/hydrolysis of step f) takes place in the presence of a suitable metal catalyst, expediently a precious metal catalyst such as Pt, Pd or Rh either applied on an inert support such as charcoal or alumina, or in complexed form. Preferred catalyst is 5 to 10% palladium on carbon (Pd/C).
[0092] The catalyst is suitably used in an amount of 2 to 30 wt. %, preferably, 5 to 20 wt. % relating to the 2-aminoalcohol of formula V.
[0093] The isomerization/hydrolysis is advantageously carried out in an aqueous solvent. The solvent itself can be protic or aprotic. Suitable protic solvents are e.g. alcohols such as methanol, ethanol or isopropanol. Suitable aprotic solvent is e.g. acetonitrile or dioxane.
[0094] The reaction temperature is preferably chosen in the range of 20° C. and 150° C.
[0095] It was found that isomerization/hydrolysis is preferably effected in the presence of a primary amine.
[0096] Primary amines suitably used are ethylenediamine, ethanolamine, or suitable derivatives of these primary amines mentioned hereinbefore. A particularly interesting primary amine is ethanolamine.
[0097] The primary amine is suitably used in an amount of 1.0 to 1.25 equivalents, preferably of 1.05 to 1.15 equivalents relating to the 2-aminoalcohol of formula V.
[0098] As a rule the 1,2-diamino compound of formula I can be isolated e.g. by evaporation and crystallization, but it is preferably kept in e.g. an ethanolic solution and then further transformed into a pharmaceutically acceptable addition salt following the methods described in J. C. Rohloff et al., J. Org. Chem., 1998, 63, 4545-4550; WO 98/07685).
[0099] Preferred pharmaceutically acceptable acid addition salt is the 1:1 salt with phosphoric acid which can be formed preferably in ethanolic solution at a temperature of 50° C. to −20° C.
[0100] The following examples shall illustrate the invention in more detail without limiting it.
EXAMPLE 1
Preparation of (3R,4R,5S)-5-amino-4-acetylamino-3-(1-ethyl-propoxy)-cyclohex-1-ene-carboxylic acid ethyl ester from (3R,4S,5R)-5-amino-3,4-dihydroxy-cyclohex-1-enecarboxylic acid
(a). Preparation of (3R,4S,5R)-5-amino-3,4-dihydroxy-cyclohex-1-enecarboxylic acid ethyl ester Preparation of (3R,4S,5R)-5-amino-3,4-dihydroxy-cyclohex-1-enecarboxylic acid ethyl ester methanesulfonic acid
[0101] In a 500 ml round bottom flask equipped with a reflux condenser, a magnetic stirrer and an inert gas supply, 13.7 g (70.0 mmol) (3R,4S,5R)-5-amino-3,4-dihydroxy-cyclohex-1-enecarboxylic acid was suspended with 120 ml ethanol and treated with 4.50 ml (70.0 mmol) methanesulfonic acid, the mixture was heated to reflux for 1 hour, the reaction mixture was cooled to about 30° C. and evaporated in a rotary evaporator at 40° C./60 mbar. The resulting residue was treated again with 120 ml ethanol, heated to reflux for 1 hour and evaporated. This operation was repeated 6 times. The residue was dried at 50° C./10 mbar to yield as the crude intermediate 20.8 g (3R,4S,5R)-5-amino-3,4-dihydroxy-cyclohex-1-enecarboxylic acid ethyl ester methanesulfonate as a brown residue.
[0102] IR (film) 3350, 2982, 1715, 1252, 1097 cm-1; MS (electron impact) 201 M
Preparation of (3R,4S,5R)-5-amino-3,4-dihydroxy-cyclohex-1-enecarboxylic acid ethyl ester hydrochloride
[0103] In a 50 ml round bottom flask equipped with a reflux condenser, a magnetic stirrer and an inert gas supply, 1.91 g (10.0 mmol) (3R,4S,5R)-5-amino-3,4-dihydroxy-cyclohex-1-enecarboxylic acid mono hydrate was suspended with 19 ml ethanol and cooled to 0-5° C., treated slowly (3 min) with 0.80 ml (11.0 mmol) thionyl chloride, then 1.28 ml (10.0 mmol) diethyl sulfite was added, the mixture was heated to reflux for 3 hours (a gas mixture was evolved), the black reaction mixture was cooled to 20-25° C., to the black suspension, 19 ml ethyl acetate was added dropwise in the course of 30 min, then the mixture was cooled to 0-5° C. and stirred for 1 hour at 0-5° C. The black suspension was filtered, the filter cake was washed portion wise with a mixture of 6.5 ml ethanol and 6.5 ml ethylacetate. The light grey crystals were dried at 40° C./10 mbar/1 h, to obtain 1.57 g (3R,4S,5R)-5-amino-3,4-dihydroxy-cyclohex-1-enecarboxylic acid ethyl ester hydrochloride, as light grey crystals.
[0104] IR (film) 3559, 2918, 1711, 1250, 1095 cm-1; MS (ion spray): 202.3 (M+H), 224.3 (M+Na) m/z mp: dec. 215° C.
(b). Preparation of (3aR,7R,7aS)-7-Amino-2,2-diethyl-3a,6,7,7a-tetrahydro-benzo [1,3]dioxole-5-carboxylic acid ethyl ester
[0105] In a 25 ml two necked round bottom flask equipped with a dean stark separator, a reflux condenser, a thermometer, a magnetic stirrer and an inert gas supply, 0.90 g (4.47 mmol) (3R,4S,5R)-5-amino-3,4-dihydroxy-cyclohex-1-enecarboxylic acid ethyl ester was suspended in 9.0 ml 3-pentanon, 0.32 ml (4.92 mmol) methanesulfonic acid was added, the mixture was heated to reflux, with a dean stark separator for 2 hours. The reaction mixture was cooled to r.t., diluted with 9.0 ml ethyl acetate and the mixture was extracted with 9.0 ml 1M aqueous sodium hydrogen carbonate solution. The organic layer was dried over about 1 g sodium sulfate and filtered. The filter cake was washed with about 9 ml of ethyl acetate and the combined filtrates were evaporated in a rotary evaporator at 40° C./10 mbar to yield as the crude intermediate 1.05 g (3aR,7R,7aS)-7-amino-2,2-diethyl-3a,6,7,7a-tetrahydro-benzo[1,3] dioxole-5-carboxylic acid ethyl ester.
[0106] MS (ion spray): 270.3 M+H, 184.2 m/z
(c). Preparation of (3R,4S,5R)-5-amino-3-(1-ethyl-propoxy)-4-hydroxy-cyclohex-1-enecarboxylic acid ethyl ester
[0107] In a 250 ml two necked round bottom flask equipped with a thermometer, magnetic stirrer and an inert gas supply, 10.80 g (40.1 mmol) (3aR,7R,7aS)-7-amino-2,2-diethyl-3a,6,7,7a-tetrahydro-benzo[1,3]dioxole-5-carboxylic acid ethyl ester was dissolved in 110 ml dichloromethane, cooled to −70° C., 7.0 ml (44.1 mmol) triethylsilane was added at −70° C., 4.85 ml (44.1 mmol) titanium tetrachloride was added slowly to the reaction mixture at −70° C. The reaction mixture was stirred 18 h at −20° C. to −25° C., then 1.05 ml (6.6 mmol) triethylsilane was added at −20° C. to −25° C. and stirred for another 6 h at −20° C. to −25° C. The reaction mixture was added slowly to an aqueous 1M ammonium hydroxide solution. 100 ml ethyl acetate were added, the mixture was filtered and washed with 200 ml ethyl acetate. The organic layer was separated and the aqueous layer was extracted with 100 ml ethyl acetate. The combined organic layers were dried over 300 g sodium sulfate, filtered, washed with 200 ml ethyl acetate and evaporated in a rotary evaporator at 40° C./600-10 mbar to yield as the crude 12.08 g of a beige oil. Purification of the crude product was obtained via a silica column chromatography using ethyl acetate with 1% of conc. aqueous ammonia as eluent. The combined fractions were evaporated and dried on a rotary evaporator to obtain 5.1 g of (3R,4S,5R)-5-amino-3-(1-ethyl-propoxy)-4-hydroxy-cyclohex-1-enecarboxylic acid ethyl ester as a yellowish oil.
[0108] MS (ion spray): 272.3 (M+H), 294.4 (M+Na) m/z
(d). Preparation of (3R,4R,5S)-5-allylamino-4-amino-3-(1-ethyl-propoxy)-cyclohex-1-enecarboxylic acid ethyl ester
[0109] In a 414-necked round bottom flask equipped with Dean-Stark trap, a thermometer, a mechanical stirrer and an inert gas supply 271.4 g of (3R,4S,5R)-5-amino-3-(1-ethyl-propoxy)-4-hydroxy-cyclohex-1-enecarboxylic acid ethyl ester obtained according to (c) were dissolved at room temperature and stirring under argon in 2710 ml of tert.-butyl methyl ether. The red solution was treated with 102.1 ml of benzaldehyde (d=1.05, 1.01 mol) and heated at reflux for 2 h during which time about 9 ml of water separated. In the course of 30 min 1350 ml of tert.-butyl methyl ether were distilled. The red solution containing the intermediate was cooled to 0° C.-5° C. and treated with 167.3 ml of triethylamine (d=0.726, 1.18 mol). Then 77.7 ml of methanesulfonyl chloride (d=1.452, 0.99 mol) were added dropwise keeping the temperature in the range of 0° C. to 5° C. in the course of 85 min during which time an orange precipitate formed. After stirring for 45 min without cooling HPLC analysis showed about 15% of the intermediate (3R, 4R, 5S)-5-(benzylidene-amino)-4-hydroxy-cyclohex-1-enecarboxylic acid ethyl ester. After dropwise addition of 7.8 ml of methanesulfonyl chloride (d=1.452, 0.09 mol) at room temperature and stirring for 10 min HPLC analysis showed about 8% of the above intermediate. After dropwise addition at room temperature of 7.8 ml of methanesulfonyl chloride (d=1.452, 0.09 mol) and stirring for 15 min HPLC analysis showed less than 1% of that intermediate. The orange suspension was filtered and the yellow-orange filter cake was washed with 300 ml of tert.-butyl methyl ether. The combined filtrates (1291 g) containing the intermediate (3R, 4R, 5S)-5-(benzylidene-amino)-4-mesyloxy-cyclohex-1-ene carboxylic acid ethyl ester were treated with 300.5 ml of allylamine (d=0.76, 4.0 mol) and the clear red solution was heated in a 31 autoclave under 1 bar of argon with stirring to 110° C.-111° C. in the course of 45 min, then stirred at this temperature and at a pressure of 3.5 to 4.5 bar for 15 h, cooled to less than 45° C. during 1 h. The red solution was evaporated in a rotary evaporator at 48° C./600 to 10 mbar and the remaining red gel (566 g) was dissolved with intensive stirring in a two phase mixture of 1000 ml of 2N hydrochloric acid and 1000 ml of ethyl acetate. The organic phase was extracted with 1000 ml of 2N hydrochloric acid, the combined aqueous phases were washed with 500 ml of ethyl acetate, cooled to 10° C. and treated with stirring with about 256 ml of 50% aqueous potassium hydroxide until pH=10.1 was reached keeping the temperature in the range of 101C to 20° C. The organic phase was separated and the aqueous phase was extracted first with 1000 ml, then with 500 ml, in total with 1500 ml of tert.-butyl methyl ether and the combined extracts were evaporated in a rotary evaporator at 48° C./340 to 10 mbar to yield crude (3R,4R,5S)-5-allylamino-4-amino-3-(1-ethyl-propoxy)-cyclohex-1-enecarboxylic acid ethyl ester (277.9 g) as a red-brown oil.
[0110] IR (film): 2966, 1715, 1463, 1244, 1090 cm −1 ; MS (EI, 70 eV): 310 (M), 222, 136, 98 m/z.
(e). Preparation of (3R,4R,5S)-4-acetylamino-5-allylamino-3-(1-ethyl-propoxy)-cyclohex-1-enecarboxylic acid ethyl ester
[0111] In a 414-necked round bottom flask equipped with a thermometer, a mechanical stirrer, a Claisen condenser and an inert gas supply 278.0 g of (3R,4R,5S)-5-allylamino-4-amino-3-(1-ethyl-propoxy)-cyclohex-1-enecarboxylic acid ethyl ester obtained according to (d) were dissolved at room temperature with stirring under argon in 2800 ml of tert.-butyl methyl ether. From the red solution 1400 ml of tert.-butyl methyl ether were distilled. Again 1400 ml of tert.-butyl methyl ether were added and distilled off. The red solution was cooled to 0-5° C. and treated with 512 ml of acetic acid (9.0 mol) whereby the temperature rose to about 23° C. After cooling to 0° C.-5° C. 58.1 ml of methanesulfonic acid (d=1.482, 0.90 mol) were added dropwise in the course of 27 min followed by 84.7 ml of acetic anhydride (d=1.08, 0.90 mol) added dropwise in the course of 40 min keeping the temperature in the range of 0° C. to 5C. The brown reaction mixture was stirred without cooling for 14 h then treated with vigorous stirring with 1400 ml of water (deionized) for 30 min and the brown organic phase was extracted with 450 ml of 1M aqueous methanesulfonic acid. The combined aqueous phases (pH=1.6) were treated with stirring with about 694 ml of 50% aqueous potassium hydroxide until pH=10.0 was reached, keeping the temperature in the range of 10 to 25° C. The brown, turbid mixture was extracted first with 1000 ml then with 400 ml, in total with 1400 ml of tert.-butyl methyl ether, the combined organic extracts were stirred over 32 g of charcoal and filtered. The filter cake was washed with about 200 ml tert.-butyl methyl ether and the combined filtrates were evaporated in a rotary evaporator at 47° C./380 to 10 mbar to yield 285.4 g of brown-red, amorphous crystals which were dissolved with stirring in a mixture of 570 ml of tert.-butyl methyl ether and 285 ml of n-hexane at 50° C. The brown solution was cooled in 45 min with stirring to −20° C. to −25° C. and stirred for 5 h whereby brown crystals precipitated. The suspension was filtered over a pre-cooled (−20° C.) glass filter funnel and the filter cake was washed with a pre-cooled (−20° C.) mixture of 285 ml of tert.-butyl methyl ether and 143 ml of n-hexane and dried in a rotary evaporator at 48° C.<10 mbar to yield 200.33 g (83%) of (3R,4R,5S)-4-acetylamino-5-allylamino-3-(1-ethyl-propoxy)-cyclohex-1-enecarboxylic acid ethyl ester; m.p. 100.2° C.-104.2° C.
(f). Preparation of (3R,4R,5S)-4-acetylamino-5-amino-3-(1-ethyl-propoxy)-cyclohex-1-enecarboxylic acid ethyl ester
[0112] In a 114-necked round bottom flask equipped with a thermometer, a mechanical stirrer, a reflux condenser and an inert gas supply 176.2 g of (3R,4R,5S)-4-acetylamino-5-allylamino-3-(1-ethyl-propoxy)-cyclohex-1-enecarboxylic acid ethyl ester obtained according to (d) and 30.0 ml of ethanolamine (d=1.015, 0.54 mol) were dissolved at room temperature in 880 ml of ethanol and treated with 17.6 g of 10% palladium on charcoal. The black suspension was heated to reflux for 3 h, cooled to room temperature and filtered. The filter cake was washed with 100 ml of ethanol and the combined filtrates were evaporated in a rotary evaporator at 50° C./<20 mbar. The brown, oily residue (207.3 g) was treated with 600 ml of 2N hydrochloric acid and the brown solution was distilled in a rotary evaporator at 50° C./75 mbar for 5 min. The solution was cooled to room temperature, washed with 600 ml of tert.-butyl methyl ether and treated with stirring and cooling with about 110 ml of 25% aqueous ammonia keeping the temperature below room temperature until pH=9-10 was reached and a brown emulsion formed. The emulsion was extracted three times with 600 ml, in total with 1800 ml of ethyl acetate. The combined extracts were dried over about 200 g of sodium sulfate and filtered. The filter cake was washed with about 200 ml of ethyl acetate and the combined filtrates were evaporated in a rotary evaporator at 50° C./<20 mbar to yield 158.6 g of a brown oil which was dissolved in 650 ml ethanol. The brown solution was added in the course of 1 min with stirring to a hot solution (50° C.) of 57.60 g of 85% ortho-phosphoric acid (d=1.71, 0.50 mol) in 2500 ml of ethanol. The resulting solution was cooled in the course of 1 h to 22° C. At 40° C. seed crystals of (3R,4R,5S)-4-acetylamino-5-amino-3-(1-ethyl-propoxy)-cyclohex-1-enecarboxylic acid ethyl ester (about 10 mg) were added whereby crystallization started. The beige suspension was cooled in the course of 2 h to −20° C. to −25° C. and stirred at this temperature for 5 h. The suspension was filtered over a pre-cooled (−20° C.) glass filter funnel for 2 h. The filter cake was first washed with 200 ml of ethanol pre-cooled to −25° C., then twice with 850 ml, in total with 1700 ml acetone, then twice with 1000 ml, in total with 2000 ml of n-hexane, then dried at 50° C./20 mbar for 3 h to yield 124.9 g (70%) of (3R,4R,5S)-4-acetylamino-5-amino-3-(1-ethyl-propoxy)-cyclohex-1-ene carboxylic acid ethyl ester as white crystals; m.p. 205-207° C., decomposition.
EXAMPLE 2
Preparation of (3R,4R,5S)-5-amino-4-acetylamino-3-(1-ethyl-propoxy)-cyclohex-1-ene-carboxylic acid ethyl ester from (3R,4S,5R)-5-amino-3,4-dihydroxy-cyclohex-1-enecarboxylic acid
[0113] Steps (a), (b), (c), (e) and (f) were performed as described above in Example 1.
[0114] Step (d), preparation of (3R,4R,5S)-5-allylamino-4-amino-3-(1-ethyl-propoxy)-cyclohex-1-enecarboxylic acid ethyl ester from (3R,4S,5R)-5-amino-3-(1-ethyl-propoxy)-4-hydroxy-cyclohex-1-enecarboxylic acid ethyl ester, was carried out as set out below.
[0115] An autoclave with a 500 ml metal reactor equipped with a thermometer, a mechanical stirrer and an inert gas supply was charged under argon with 40.70 g of (3R,4S,5R)-5-amino-3-(1-ethyl-propoxy)-4-hydroxy-cyclohex-1-enecarboxylic acid ethyl ester (0.12 mol) obtained according to (b) and 200.0 ml of ethyl formate and the solution was heated with stirring to 100° C. at 4 to 5 bar in the course of 35 min, kept at this temperature for 6 h, then cooled to room temperature. The red solution was treated and evaporated twice with 150 ml, in total with 300 ml of toluene and evaporated at 45° C./300-15 mbar to yield as the crude intermediate 46.24 g of (3R,4R,5R)-5-formylamino-4-hydroxy-3-(1-ethyl-propoxy)-cyclohex-1-enecarboxylic acid ethyl ester as a red oil.
[0116] IR (film): 2967, 1715, 1385, 1247, 1100 cm −1 ; MS (electron spray): 300 (M+H + ), 270 (M − COH), 253, 212, 138 m/z.
[0117] In a 114-necked round bottom flask equipped with a reflux condenser, a thermometer, a mechanical stirrer and an inert gas supply 46.24 g of the above crude intermediate (0.15 mol) were dissolved in 460 ml of ethyl acetate and 23.7 ml triethylamine (d=0.726, 0.17 mol). The orange solution was cooled to 0° C. to 5° C. and treated dropwise in the course of 30 min with 13.2 ml of methanesulfonyl chloride (d=1.452, 0.17 mol) during which time a white precipitate formed. After stirring for 60 min without cooling the suspension reached room temperature. After 45 min at room temperature the white suspension was filtered and the filter cake was washed with 45 ml of ethyl acetate. The combined filtrates were washed with 116 ml of 1M aqueous sodium bicarbonate solution, dried over 130 g of sodium sulfate, filtered and evaporated in a rotary evaporator at 45° C./180 to >10 mbar to yield as the crude intermediate 58.39 g of (3R,4R,5R)-5-formylamino-4-methanesulfonyloxy-3-(1-ethyl-propoxy)-cyclohex-1-enecarboxylic acid ethyl ester as an orange-red oil.
[0118] IR (film): 2967, 1715, 1358, 1177, 968 cm −1 ; MS(EI, 70 eV): 377(M), 290, 244, 148, 96 m/z.
[0119] In a 114-necked round bottom flask equipped with a reflux condenser, a thermometer, a mechanical and an inert gas supply 58.39 g of the above crude intermediate were dissolved in 290 ml of ethanol. The orange solution was treated with 10.7 ml of methanesulfonic acid (d=1.482, 0.17 mol) and heated to reflux for 160 min. The red-brown reaction was evaporated in a rotary evaporator at 45° C./190 to 30 mbar and the remaining red-brown oil was treated with 260 ml of deionized water and washed with 260 ml of tert.-butyl methyl ether. The organic phase was extracted with 52 ml of deionized water and the combined aqueous phases (pH=1.3) were cooled to 0° C. to 5° C. and treated with 13.7 ml of 50% aqueous potassium hydroxide keeping the temperature below 10° C. until pH=9.4 was reached whereby a beige emulsion formed. At a pH of 6.6 260 ml of ethyl acetate was added. The aqueous phase was extracted with 70 ml of ethyl acetate and the combined organic extracts were dried over 160 g of sodium sulfate, filtered and evaporated in a rotary evaporator at 45° C./190 to 20 mbar to yield as the crude intermediate 45.66 g of (3R,4R,5R)-5-amino-4-methansulfonyloxy-3-(1-ethyl-propoxy)-cyclohex-1-ene carboxylic acid ethyl ester as a red oil.
[0120] IR (film): 1720, 1362, 1250, 1170, 1070; MS(electronspray): 350, 3(M + H + ), 290.3, 262.1, 202.2, 184.3 m/z.
[0121] An autoclave with a 500 ml glass reactor equipped with a thermometer, a mechanical stirrer and an inert gas supply was charged under argon with a red solution of 45.66 g (0.13 mol) of the crude intermediate above and 29.5 ml of allylamine (d=0.76, 0.39 mol) and 250 ml of ethyl acetate. The mixture was heated under 1 bar of argon with stirring to 111° C. to 112° C. in the course of 45 min, kept at this temperature at about 3.5 bar for 6 h, then cooled to room temperature in the course of 50 min. The orange suspension was vigorously stirred for 20 min with 230 ml of 1M aqueous sodium bicarbonate solution. The red brown organic phase was dried over 100 g of sodium sulfate and filtered. The filter cake was washed with about 50 ml of ethyl acetate and the combined filtrates were evaporated in a rotary evaporator at 45° C./160 to 10 mbar to yield as the crude intermediate 41.80 g of (3R,4R,5S)-5-allylamino-4-amino-3-(1-ethyl-propoxy)-cyclohex-1-ene carboxylic acid ethyl ester as a red oil.
[0122] IR (film): 3441, 1707, 1462, 1262, 1063 cm −1 ; MS (electronspray): 311.2(M + ,H + ), 297.2, 266.3, 245.8, 223.2 m/z. | The present invention relates to a process for the preparation of a 4,5-diamino shikimic acid derivative of formula
and pharmaceutically acceptable addition salts thereof wherein
R 1 , R 1′ are independent of each other H or alkyl, R 2 is an alkyl and R 3 , R 4 are independent of each other H or an alkanoyl, with the proviso that not both R 3 and R 4 are H. 4,5-diamino shikimic acid derivatives of formula I, especially the (3R,4R,5S)-5-amino-4-acetylamino-3-(1-ethyl-propoxy)-cyclohex-1-ene-carboxylic acid ethyl ester and its pharmaceutically acceptable additional salts are potent inhibitors of viral neuraminidase. | 2 |
BACKGROUND OF THE INVENTION
This invention relates to a sliver coiler including a support arrangement for positioning the running sliver as it is delivered by a carding machine, a rotary head assembly including an orbiting sliver trumpet through which the sliver passes as it runs from the support arrangement; and calender rollers arranged underneath the sliver trumpet and orbiting therewith. After the sliver passes through the calender rollers, it is deposited in continuous coils into a rotating coiler can disposed underneath the rotary head assembly.
In a known apparatus the sliver supporting arrangement includes a sliver deflecting roller which is situated above the rotary head assembly and which rotates about an approximately horizontal axis. The distance between the sliver deflecting roller and the rotary head assembly is greater than the radius of the rotary head assembly, and the angle of the connecting line between the trumpet and the roller to the (generally horizontal) plane in which the head asssembly rotates is approximately 70°. In such an arrangement, at high sliver speeds of, for example, more than 300 m/min, the risks are high that the unsupported sliver significantly bulges outwardly under the effect of centrifugal forces and may rupture.
SUMMARY OF THE INVENTION
It is an object of the invention to provide an improved apparatus of the above-outlined type from which the discussed disadvantage is eliminated and which thus may operate at high speeds without the risks of disturbances, such as sliver rupture.
This object and others to become apparent as the specification progresses, are accomplished by the invention, according to which, briefly stated, the angle of a line connecting a sliver supporting arrangement above the rotary head assembly and the sliver trumpet mounted in the rotary head assembly, forms a maximum angle of 45° with the plane in which the rotary head assembly rotates.
It is a significant characteristic of the apparatus according to the invention that the sliver running from the deflecting (sliver supporting) arrangement above the rotary head assembly to the sliver trumpet forms a small (flat) angle with the generally horizontal plane in which the rotary head assembly revolves. In this manner the magnitude of the centrifugal force component which causes an outward bulging of the free length portion of the sliver between the supporting (deflecting) arrangement and the sliver trumpet is significantly reduced. As a result, significantly higher operational speeds are possible (in excess of 300 m/min) without rupture of the sliver. Also, a higher output of the sliver coiler is ensured.
According to a further feature of the invention, the distance between the sliver supporting arrangement and the rotary head assembly is equal to or is smaller than the radius of the rotary head assembly. Such an arrangement ensures that the angle α will have the small value according to the invention.
According to a further feature of the invention, the sliver supporting arrangement is constituted by a trumpet-like guide element which functions as a predensifier. As the sliver passes through the trumpet-like guide element, air is pressed out of the sliver, thus reducing the diameter of the sliver and rendering it more stable and less prone to rupture.
According to a further feature of the invention, the guide element has, in its wall, at least one recess through which air flowing in the reverse direction due to the precompression in the trumpet-like guide element is removed.
In accordance with a further feature of the invention, upstream of the guide element - as viewed in the direction of sliver run - there is provided at least one further sliver support which is preferably constituted by a trough in which the sliver is guided to the deflecting support arrangement while shielding the sliver from interfering lateral air streams.
According to still another feature of the invention, the second sliver support is a backup plate which has at least a zonewise shingle-like (stepped) configuration. Such a construction causes the sliver to glide on an air cushion as it travels on the backup plate.
According to another feature of the invention, a hood is provided which extends over one part of the sliver coiler, whereby the sliver is screened from interfering air streams. Expediently, the guide element is situated underneath the hood, whereby interfering air streams are screened from the zones of the sliver upstream of the guide element as well as between the guide element and the sliver trumpet.
In accordance with a further feature of the invention, a suction device is connected with the hood to remove dust and other released waste.
According to still another feature of the invention, the upper part of the hood is pivotal to provide for an easy manual access underneath the hood, particularly for the purpose of facilitating the start-up, by introducing the sliver manually into the sliver trumpet.
According to another advantageous feature of the invention, inside the hood, about the rotary head assembly, there is provided a circularly bent shielding element which prevents dust and similar waste from accumulating in the edge zones of the hood. The space which is surrounded by the shielding element is expediently exposed to vacuum. Further, by virtue of the cylindrical shape of the shielding element, the flow-dynamic characteristics of the air current generated by the rapidly rotating coiler head assembly are improved and rendered more uniform.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a schematic sectional side elevational view of a preferred embodiment of the invention.
FIG. 2a is a schematic axial side elevational view of another preferred embodiment of the invention, shown in a closed position.
FIG. 2b is a view similar to FIG. 2a, illustrating the structure in an open position.
FIG. 3 is an axial sectional view of a further preferred embodiment of a component according to the invention.
FIG. 4 is a schematic side elevational view of a preferred embodiment of a further component forming part of the invention.
FIG. 5 is a schematic perspective view of another preferred embodiment of a component of the invention.
FIG. 6 is a top plan view of the structure shown in FIG. 2a, illustrating a preferred embodiment of a further component of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Turning to FIG. 1, there is illustrated therein a sliver coiler arranged at the output end of a carding machine (not shown) which delivers a fiber sliver 6. The sliver coiler has a stationary head support plate assembly 1 in which a rotary head assembly 2 is mounted. The latter carries a trumpet 3, supply rollers (calender rollers) 4 and a pressing plate 5 whose underside is substantially coplanar with that of the head supporting plate assembly 1.
During normal operation, the calender rollers 4 are driven such that the sliver 6 which is admitted to the rotary head assembly 2 by passing through the trumpet 3, is deposited in a coiler can 7 which is arranged underneath the head support plate assembly 1 and the rotary head assembly 2. The coiler can 7 rotates as the sliver 6 is deposited by the rotary head assembly 2. The sliver coils deposited in the coiler can 7 project upwardly beyond the upper edge of the coiler can 7 and thus engage the planar undersides of the head support plate assembly 2 and the pressing plate 5 during the major part of the can filling operation and after the completion thereof.
Also referring to FIG. 3, generally centrally above the rotary head assembly 2 there is provided a trumpet-like guide element 8 which has the shape of two back-to-back arranged funnels and which is fixedly mounted on a holding element 9. Upstream of the guide element 8 - as viewed in the direction of sliver run - there is provided a further sliver support element 10 which may be, for example, a sheet metal tray. The sliver, delivered by the carding machine, runs on the slightly bent, substantially horizontally oriented sliver support 10 to the guide element 8 where it enters its funnel-like opening 8a, passes through the constriction 8b and exits the guide element 8 through the outwardly flaring funnel-like outlet opening 8c in the downward direction and is deflected towards the sliver trumpet 3. The angle formed by a straight line connecting the center of the outlet 8c of the guide element 8 with the center of the inlet of the trumpet 3, with the generally horizontal plane in which the rotary head assembly 2 rotates is approximately 30°. This geometrical arrangement ensures that the sliver 6 is guided at a small (flat) angle from the guide element 8 to the trumpet 3 relative to the plane in which the rotary head assembly 2 revolves, whereby the centrifugal forces generated by the rotation of the head assembly 2 have a significantly reduced effect on the sliver 6.
As the sliver passes through the constriction 8b of the guide element 8 air is expelled by compression from the sliver 6 whereby the latter is precompressed and thus made more stable and less prone to rupture.
Turning now to the embodiment illustrated in FIGS. 2a and 2b, above the head support plate assembly 1 there is provided a hood or box 11 which has an upper lid or ceiling wall 11a. In a lateral wall of the hood 11 there is provided an aperture 11b through which the sliver 6, as it is guided on a roller 12, is introduced in the inner space of the hood 11. In addition, as indicated by the arrow A, air is entrained into the inner space of the hood 11. In the lateral zone of the hood 11 there is further provided an aperture 11c to which there is connected a suction device (not shown) for removing air as indicated by the arrow B. In the inside of the hood 11 the guide element 8 is arranged above the rotary head assembly 2. The lid 11a of the hood 11 is upwardly pivotal about a hinge 11d as illustrated by the arrow D in FIG. 2b. In the upwardly pivoted position of the lid 11a an easy manual access is provided, particularly for the purpose of facilitating the manual insertion of the sliver 6 into the guide element 8 and the trumpet 3 for the start-up operation.
Reverting to FIG. 3, in the guide element wall defining the inlet portion 8a of the guide element 8 there is provided a recess 8d through which air is removed as it flows in the upstream direction after being expelled from the sliver as it passes through the constriction 8b. The constriction 8b may be of slighter greater diameter than the inlet of the sliver trumpet 3 whereby a pre-densification of the sliver 6 is effected by the guide element 8.
According to the embodiment illustrated in FIG. 4, upstream of the trumpet-like guide element 8 a sliver supporting plate 10' is arranged which has a shingle-like (stepped) surface 10a. By virtue of this arrangement, the sliver running on the plate 10' towards the guide element 8 rides on an air cushion.
According to the embodiment of FIG. 5, the sliver support situated upstream of the guide element 8 is constituted by a trough 10" which has a bottom face 10b and two lateral guide walls 10c.
Turning now to FIG. 6, the rotary head assembly 2-whose rotary direction is indicated by the arrow C-is mounted in an angular hood or box 11'. About the rotary head assembly 2 in the inner space of the box 11' there is provided a stationary, circularly bent shielding element 13 which may be of sheet metal and which is in an upright, edgewise standing position on the head support plate assembly 1. The shield 13 is provided with a suction nipple 13a for removing dust or other waste.
It will be understood that the above description of the present invention is susceptible to various modifications, changes and adaptations, and the same are intended to be comprehended within the meaning and range of equivalents of the appended claims. | A sliver coiler includes a rotary head assembly, a sliver trumpet eccentrically mounted in the rotary head assembly and a sliver guide element situated generally centrally above the rotary head assembly at a distance therefrom, whereby the sliver has an unsupported running portion from the sliver guide element to the sliver trumpet. The angle formed between the plane of rotation of the rotary head assembly and a line connecting the sliver guide element with the sliver trumpet is 30° at the most. | 3 |
BACKGROUND
This application claims the benefit of U.S. Provisional Patent Application 60/978,913, filed Oct. 10, 2007, the entirety of which is incorporated by reference.
BACKGROUND
The invention relates to the processing of light weight, bulky cellulosic material, such as straw and other non-wood cellulosic material, to pulp. The invention particularly relates to chemical processing of such material.
Straw and other light weight, bulky cellulosic material are converted to pulp for use in paper, building materials and other pulp based products. These materials are processed by chemical and mechanical processing treatments. The chemical treatment of these materials typically involves caustic chemicals and short processing times.
Chemical treatment vessels that treat straw and other light weight, bulky cellulosic materials accommodate the severe chemical conditions and short retention times involved in the chemical processing, e.g., hydrolysis, of these materials. A conventional chemical treatment vessel includes a series of horizontal tubes arranged side-by-side and is referred to as a Pandia digester. Conduits connect the tubes and provide a flow path for material flowing from the discharge of one tube to the inlet to the next tube. The arrangement of tubes requires a relatively complex mechanical assembly to support the Pandia digester. Material undergoing treatment flows from one tube to the next.
In the tubes, the material is maintained at temperatures of 200° C. and pressures of 20 bar (about 290 pounds per square inch (psi)) with retention times of less than 30 minutes. Screws internal to each tube move the material through each tube. The screws are prone to becoming clogged with the material and require maintenance.
The multiple tubes make the Pandia digester a mechanically complex device having a large number of moving components, e.g., screws. There is a long felt need for treatment vessels having few moving components, at least as compared to the multiple screw conveyors in a Pandia digester. There is also a long felt need for chemical treatment vessel capable of processing large volumes of material, such as 400 tons per day with a four minute retention time in the vessel. Accordingly, there is a long felt need for a chemical treatment vessel having a relatively simple structure and capable of processing large volumes of straw and other light weight bulky cellulosic materials.
SUMMARY OF THE INVENTION
A single vessel has been developed for chemical treatment of light weight, bulky cellulosic material, such as straw and other non-wood cellulosic material. The vessel is preferably predominantly a cylinder having an interior treatment chamber with a sealed top and bottom to allow for pressures of at least 20 bar and preferably 40 bar and temperatures of at least 100° C. and preferably 200° C. The treatment chamber is substantially vertical, e.g., within 10 degrees of vertical, and may have a diameter of 1.5 to 4 meters and a height of 0.5 to 20 meters, depending on the desired volumetric flow rate and retention time of material in the chamber.
The material may be introduced through an upper inlet port to the vessel. Treatment liquids (if needed these liquids are preferably acidic chemicals to support hydrolysis, although treatments with ammonia are also suitable) and water may be added to promote treatment of the material in the chamber and to transport the material through a lower discharge. Anti-compression rings may be arranged in the upper elevations of the chamber and agitators may be included proximate to the anti-compression rings. The bottom discharge of the chamber may include devices to facilitate discharge of the material, such as one-dimensional sidewall transitions of the chamber to promote material flow, rotation devices to move material to the discharge, and baffles to allow for the injection of fluid in the bottom of the chamber that increases the fluid to material ratio as the material is discharged from the chamber or combinations thereof.
A method has been developed to chemically treat light weight, bulky cellulosic material including: introducing the material to an upper inlet of a substantially vertical treatment vessel; maintaining the material in the vessel at a pressure of at least 20 bar and at a temperature of at least 200° C.; treating the material with a cooking liquor in the vessel; moving the material past at least one anti-compression ring on an inside surface of the vessel, as the material moves downward through the vessel; agitating the material in the vessel, and discharging the treated material from a lower discharge port of the vessel.
A treatment vessel has been developed for chemically treating light weight, bulky cellulosic material, the vessel comprising: a generally vertical vessel having a sealed top and bottom and a sidewall extending from the top to the bottom, wherein the vessel is operated at a pressure of at least 20 bar and at a temperature of at least 200° C.; a material inlet port in an upper section of the vessel, wherein the inlet port receives the cellulosic material; a cooking liquor inlet port in the vessel or in a material feed system coupled to the material inlet port; at least one anti-compression ring on an inside surface of the sidewall; an agitator proximate to the anti-compression ring and agitating the material in the vessel, and a discharge outlet in a lower portion of the vessel.
SUMMARY OF THE DRAWINGS
A preferred embodiment and best mode of the invention is illustrated in the attached drawings that are described as follows:
FIG. 1 is a schematic diagram of a treatment vessel for chemical treatment, e.g., digesting, of light weight, bulky cellulosic material to produce, for example, pulp.
FIG. 2 is a cross-sectional diagram of an exemplary anti-compression ring for the vessel shown in FIG. 1 .
FIG. 3 is a side view of a discharge section of the vessel shown in FIG. 1 .
DETAILED DESCRIPTION
FIG. 1 schematically illustrates a chemical treatment vessel 10 that has been developed to treat light weight, bulky cellulosic materials, such as straw (“collectively referred to as light weight cellulosic material”). By way of example, light weight cellulosic material has a density of 50 to 120 kg/m3 (kilograms per meter cubed) which is less dense than conventional wood chips. In the example disclosed herein, the vessel 10 is a vertical reactor capable of processing 400 tons per day of the light weight cellulosic material and having a volumetric capacity of 14 cubic meters. The vessel 10 may be a closed vessel having a cylindrical body having a constant diameter circular cross-section and the body has sealed upper and lower ends.
In one embodiment, the cylindrical vessel 10 has a diameter of 1.5 meters and a height of 8 meters. In other embodiments, the vessel may have a diameter in a range of 1 meter to 10 meters, or a narrower range of 3 to 4 meters. The height of the vessel may be in a range of 0.5 meters to 40 meters. The diameter and height of the vessel may be selected depending on the desired volumetric rate of material to flow through the vessel and the retention time of material in the vessel.
The shape of the vessel may differ from the exemplary cylindrical vessel embodiment disclosed herein. The vessel may have a non-circular cross-sectional shape and dimensions different that are not constant, such as a conical body, a rectangular or elliptical body, and a body that has a shape more complex than a simple cylindrical, rectangular or elliptical (in cross-section) shape. A preferred characteristic of the vessel is that it be a single vessel, in contrast to the multiple tubes of prior art treatment vessels.
The vessel should be capable of operating at least at 20 bar pressure and 200° C. of temperature, and preferably at 40 bar pressure (approximately 580 psi) and 300° C. of temperature. These temperature and pressure conditions are suitable for processing light weight cellulosic material by treatments such as hydrolysis. Any liquid to be added to the vessel, such as liquor and cooling liquid to facilitate transport of the material through the discharge of the vessel, should preferably be added as water or be acidic. Organic treatment fluids may also be used, such as acetic acid, formic acid, ethanol and methanol. In one example, the vessel 10 may be used, for example, to treat non-wood lightweight cellulosic material, e.g., straw, by hydrolysis under acidic treatment conditions. In one embodiment, the retention time of the material in the vessel is preferably between 10 minutes and 120 minutes, where longer retention times may be more advantageous.
The operation of the vessel 10 may include conventional devices for controlling the flow of cellulosic material in a chemical treatment vessel, such as material level control. The control system may monitor a solids level in the vessel using, for example, a gamma gauge, and provide a feedback signal used to control the rate of material entering the vessel from the material feed system 12 and the discharge rate of pulp from the bottom discharge 20 . In addition, force sensors, e.g., strain gauges, may be included in the vessel to monitor pressures and forces in the vessel. Further, sensors may monitor the rotating speed of moving components in the system, such as a screw conveyor in the feed system 12 and the movement of the agitators.
The retention time and temperature of the cellulosic material in the vessel is preferably controlled and maintained at uniform levels. Control of the retention time and temperature assists in achieving the desired yield of products from the chemical reactions of the material and liquor in the vessel. Further, control of the retention time and temperature is needed to avoid side reactions in the vessel that may result in the loss of the desired reactions products.
The vessel 10 includes a feed system 12 for the light weight cellulosic material. The feed system may be a conventional system, such as a chip bin, chip screw conveyor with inlets for steam and liquor to facilitate transport of the material to and through the vessel. The vessel has an inlet port 14 at a top or upper section of the vessel. The feed system 12 may be used to transport the cellulosic material from a chip bin operating at atmospheric pressure to the vessel inlet 14 which is at a pressurized conditions, such as a temperature of 200° C. and a pressure of 20 bar, at which the vessel operates.
The vessel 10 is a pressurized vessel that is capable of maintaining uniform flow of the cellulosic material through the vessel. Preferably, the amount of liquor, e.g., liquids with chemicals to digest the cellulosic material to pulp, introduced to vessel is minimized to efficiently heat and maintain the temperature of the material being treated in the vessel. Heat energy 16 may be added to the vessel, such as steam, hot gases or other such hot medium.
The vessel 10 may have an inside chamber 18 having a vertical sidewall in which material flows downward to a material discharge 20 at a bottom of the vessel. Within the chamber at various locations along the sidewall, anti-compression rings 22 or other suitable rings to reduce compression of the material in the vessel. These rings facilitate movement of the cellulosic material through the vessel. The rings are arranged at various elevations in the chamber, and preferably at upper elevations of the chamber such in the upper half of the chamber.
FIG. 2 shows an exemplary anti-compression ring 22 which may be an annular ring having a generally right-sided triangular cross-sectional shape. The top 24 of the ring is attached to the inside wall 26 of the vessel and a first vertical cylindrical leg 28 attached to the inside wall 26 . The anti-compression ring may includes a sloped side wall 30 that is inclined inward to the vessel. The anti-compression ring promotes uniform compression of the flow of material throughout the height of the vessel. The rings apply a slight compression of the material moving downward along the sloped sidewall 30 of the rings. The compression applied by the rings provides support for the material in the upper elevations of the vessel and reduces the force applied to material in the lower elevations due to material in the upper elevations. As the material flows past the ring, there is a quick release of the compression force as the material flows past the bottom edge of the sidewall 30 and expands to the larger diameter of the vessel inside wall 26 . Suitable anti-compression rings are described in U.S. Pat. Nos. 6,280,569 and 5,454,490.
Agitators 32 may be included in the chamber 18 to assist the movement of material through the vessel and, particularly, past the anti-compression rings. The agitators may be positioned near and, possibly, connected to the anti-compression rings 22 . The agitator 32 may be bar or shaft connected to a surface of the vessel, e.g., sloped sidewall 30 , that applies an agitation movement, e.g., shaking, reciprocal movement and vibration. The agitation movement is applied to the cellulosic material to promote movement of the material through the vessel.
A motive force 34 is applied to agitator to impart the agitation movement. The agitator may be a conventional agitation device used to assist in the movement of the cellulosic material through a vessel. Combining the anti-compression rings and the agitators, such as applying a shaking arm(s) to the sloped sidewall 30 , may reduce the components and especially moving components in the vessel. Further, combining the agitator and anti-compression ring reduces the mechanical components in contact with the material and thus reduces the components that might disrupt the flow of material through the vessel.
FIG. 3 shows an exemplary discharge device 36 formed in a lower portion of the vessel in which the sidewall transitions from a cylindrical wall to a wall having a one dimensional convergence and side relief, such that a diamond shaped indention is formed on opposite sides of the discharge device. The discharge device 36 may comprise horizontal feed screws 38 mounted adjacent the bottom of the discharge device. A discharge device 36 in a bottom section of the vessel may be a flow promotion device such as described in U.S. Pat. Nos. 5,500,083; 5,628,873; and 5,617,975.
As an alternative to a horizontal feed screw, a rotating scraper 40 (that may be of conventional design) may be arranged in a lower section of the vessel. The scraper may push the cellulosic material to a central discharge point 42 at the bottom on the vessel.
A baffle 44 may be arranged at lower portion of the vessel which is just upstream of the discharge point 42 . The baffle sweeps material into the discharge point. Further, a dilution liquid may be introduced through conduit 44 to the baffle area. The dilution liquid flows from the baffle area to the material moving towards the discharge point. The dilution liquid increases the liquid to material ratio so as to assist in the movement of material to the discharge point.
The invention has been described in connection with the best mode now known to the applicant inventors. The invention is not to be limited to the disclosed embodiment. Rather, the invention covers all of various modifications and equivalent arrangements included within the spirit and scope of the appended claims. | A method to chemically treat light weight, bulky cellulosic material including: introducing the material to an upper inlet of a substantially vertical treatment vessel; maintaining the material in the vessel at a pressure of at least 20 bar and at a temperature of at least 200° C.; treating the material with a cooking liquor in the vessel; moving the material past at least one anti-compression ring on an inside surface of the vessel, as the material moves downward through the vessel; agitating the material in the vessel, and discharging the treated material from a lower discharge port of the vessel. | 3 |
RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional Application No. 60/281,207 filed Apr. 2, 2001 and U.S. Non Provisional application Ser. No. 09/963,779, the entire contents of which are herein incorporated by reference.
FIELD OF THE INVENTION
[0002] The present invention generally relates to a media delivery network. More particularly, the present invention relates to a software conditional access system for a media delivery network.
BACKGROUND OF INVENTION
[0003] More than ever before, residential consumers are being provided with a wealth of media resources. While cable television, the Internet, and on-demand media have been available for years, recently developed high-speed broadband technologies are enhancing the delivery of these media services. These technologies have made it possible to increase the variety of available media services and to enhance the ability of the user to interact with the media delivery system to tailor media delivery to the user's preferences. Satellite communications, asymmetric digital subscriber lines (ADSL), and broadband cable are providing new high-throughput connections to media delivery services. Media services consumers are commonly establishing wireless connections to satellites, telephony-based connections to ADSL, and broadband cable connections to the media service providers. Typically, these connections are processed by a Media Distribution Device that processes media content and data and routes the media and/or data to media presentation devices, such as a television or personal computer. A conventional Set-top Box (STB) is an example of a Media Distribution Device.
[0004] A Conditional Access System (CAS) may be used to restrict the delivery or viewing of media services. For example, a CAS may be used to prohibit a cable television (CATV) or satellite television viewer from viewing a certain pay-per-view event unless the viewer has paid to view the event. Traditionally, the CAS has required hardware smartcard technology. One such CAS has an access-enabling card (a smartcard) that is inserted into a Media Distribution Device and is able to decrypt data to view an event when the user has paid to view the event. The smartcard also includes account and billing information that is periodically uploaded via a phone line to the media service provider. For example, when a user purchases a pay-per-view event, a flash memory of the smartcard may be updated to reflect that the user purchased the event. The smartcard may provide decryption of the pay-per-view event and allow the user to view the purchased event. At a later time, such as during the early morning, the Media Distribution Device may connect via a phoneline to a billing system to update the billing system with the billing information from the smartcard. This type of CAS may be referred to as a hardware CAS because it includes a piece of hardware (smartcard) at the Media Distribution Device that is used to provide conditional access.
[0005] Although a hardware CAS works fairly well, it does have some problems. One problem is that a hardware CAS costs a great deal of money to implement, maintain and update. For example, a smartcard may cost around ten dollars. Periodically, updated smartcards need to be provided to all customers. A CATV or satellite service provider may have millions of customers. Thus, the costs of providing updated smartcards are great, Moreover, customer support must be provided to help users who have difficulty installing their new smartcards. Also, some customers may become frustrated and cancel their service, resulting in lost revenues. Moreover, the cost of smartcard readers, smartcard media and the administration process for managing smartcard distribution is high on a per device basis. Thus, a hardware CAS is expensive to implement and maintain.
[0006] Another problem with a hardware CAS is fraud. Smartcards may be cloned, hacked, stolen, duplicated, moved, etc. and these cards may be used to receive media services without paying the proper revenue to the media service providers. Even if a smartcard is not tampered with, the billing system is only periodically updated by a user's Media Distribution Device. Thus, a clever and devious user may view a pay-per-view event, but then disconnect the telephone line from their Media Distribution Device before the Media Distribution Device dials the service provider. Thus, a user may be able to delay or circumvent payment for media services due to deficiencies in the hardware CAS technology.
SUMMARY OF THE INVENTION
[0007] According to an embodiment of the present invention, a method for purchasing a media service from a media delivery service provider is provided. The method includes sending a request, by an application executing on a computer processor of a media distribution device, to the media delivery service provider requesting the media service. The method also includes authenticating, by the application, the media distribution device by comparing a permanent virtual circuit established between the media distribution device and the media delivery service provider with a predetermined permanent virtual circuit defined and programmed by the media delivery service provider. Upon determining the media distribution device is successfully authenticated, the method includes downloading a software key from the media delivery service provider to the media distribution device and automatically deleting the software key after a predetermined amount of time. Upon determining the media distribution device is not successfully authenticated, the method includes downloading displayable data to the media distribution device from the media delivery service provider.
[0008] According to another embodiment of the present invention, a computer program product for purchasing a media service from a media delivery service provider is provided. The computer program product includes a non-transitory storage medium containing instructions that when executed by a processing circuit perform a method. The method includes sending a request to the media delivery service provider for the media service and authenticating a media distribution device by comparing a permanent virtual circuit established between the media distribution device and the media delivery service provider with a predetermined permanent virtual circuit defined and programmed by the media delivery service provider. Upon determining the media distribution device is successfully authenticated, the method includes downloading a software key from the media delivery service provider to the media distribution device and automatically deleting the software key after a predetermined amount of time. Upon determining the media distribution device is not successfully authenticated, the method includes downloading displayable data to the media distribution device from the media delivery service provider.
[0009] The various aspects of the present invention may be more clearly understood and appreciated from a review of the following detailed description of the disclosed embodiments and by reference to the drawings and claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 is a block diagram of an exemplary operating environment in which embodiments of the present invention may be implemented.
[0011] FIG. 2 is a block diagram depicting some of the primary components of an exemplary Media Distribution Device.
[0012] FIG. 3 is a block diagram depicting a media delivery system with a software conditional access system (CAS) in accordance with an exemplary embodiment of the present invention.
[0013] FIG. 4 is a flow chart depicting an exemplary method for purchasing media services using a software conditional access system (CAS) in accordance with an embodiment of the present invention,
DETAILED DESCRIPTION
[0014] In one embodiment, the invention is a software conditional access system (CAS) for media services provided to a Media Distribution Device, such as a set top box (STB). The STB may be connected to a Media Delivery Service Provider via a broadband connection. Over the broadband connection, a CAS application may be downloaded to the STB, maintained and dynamically updated. Because the CAS is implemented by software on the STB, it is inexpensive to install, maintain and update.
[0015] When a user desires to purchase media services through the STB, a request is sent to the Media Delivery Service Provider via the broadband connection, A part of the request may be identifying information of the STB. For example, the MAC address of the STB or the hardware serial number of the STB may be sent with the request. The service provider then cross-references the identifying information with a user's account to determine whether to allow the user to view the media service requested. If the service provider determines to allow the user to view the media service, the user's account (typically maintained by the service provider) is charged and a key is downloaded via the broadband connection to the STB. Thus, there is no lag time between a user purchasing the media service and the user being charged for the media service.
[0016] The key allows the user to view the requested media service. For example, the key may be software that is programmed to decrypt the requested media service for viewing. After the requested media service ends, after a predetermined amount of time, etc., the CAS application may delete the key.
[0017] In one embodiment, the invention is a software conditional access system (CAS) for media services provided to a Media Distribution Device, such as a set top box (STB). The STB may be connected to a Media Delivery Service Provider via a broadband connection. Over the broadband connection, a CAS application may be downloaded to the STB, maintained and dynamically updated. Because the CAS is implemented by software on the STB, it is inexpensive to install, maintain and update.
[0018] When a user desires to purchase media services through the STB, a request is sent to the Media Delivery Service Provider via the broadband connection. A part of the request may be identifying information of the STB. For example, the MAC address of the STB or the hardware serial number of the STB may be sent with the request. The service provider then cross-references the identifying information with a user's account to determine whether to allow the user to view the media service requested. If the service provider determines to allow the user to view the media service, the user's account (typically maintained by the service provider) is charged and a key is downloaded via the broadband connection to the STB. Thus, there is no lag time between a user purchasing the media service and the user being charged for the media service.
[0019] The key allows the user to view the requested media service. For example, the key may be software that is programmed to decrypt the requested media service for viewing. After the requested media service ends, after a predetermined amount of time, etc., the CAS application may delete the key.
[0020] Having briefly described embodiments of the present invention above, a block diagram of an exemplary operating environment will be described below in reference to FIG. 1 .
[0021] FIG. 1 is a block diagram of an exemplary operating environment in which embodiments of the present invention may be implemented. Media content is typically delivered to a customer by means of a Media Distribution Device 100 . The most common Media Distribution Devices are conventional Set-Top Boxes (STBs). The Media Distribution Device (MDD) 100 can provide media content and/or data to a media presentation device 101 over a communication link 102 . The most common example of a media presentation device 101 is a conventional television, although a stereo or home theater system would also represent a media presentation device if audio content is to be purchased and played via an implementation of the invention. Typically, the MDD 100 will deliver media content only to media presentation device 101 . However, newer-generation media presentation devices 101 have the ability to process data received from the Media Distribution Device 100 . Such data may include information pertaining to the presentation of the media content on the media presentation device 101 .
[0022] Another example of a media presentation device 101 is a conventional personal computer. The personal computer can receive media content, such as Internet content from the Media Distribution Device 180 and present it to a customer/user. As is well known, a personal computer can also process data received from the Media Distribution Device 100 to format the presentation of the delivered media content. The MDD 100 can receive media content and data from one or more sources. In the example of FIG. 1 , the MDD 100 is depicted receiving media and data from a Media Delivery Service Provider 103 . Examples of a Media Delivery Service Provider are a cable T.V. provider, a satellite T.V. provider, an Internet service provider, and a telephone service provider. Notably, the media content and data may be delivered over a single communication link or may be delivered over separate communication links.
[0023] In the example of FIG. 1 , the Media Delivery Service Provider 103 can provide media content and data to the MDD 100 via an Asymmetric Digital Subscriber Line (ADSL) modem 106 . The Media Delivery Service Provider 103 may also provide media content and data to the MDD 100 via a satellite 104 . The satellite can deliver media content and data directly to the MDD 100 over a communications link 122 . Such a direct link usually involves the use of a small satellite dish in conjunction with the MDD 100 , The satellite 104 can also deliver the media content and data to the Media Delivery Service Provider 103 via another communication link 120 . This media content and data may be rerouted to the MDD 100 from the Media Delivery Service Provider 103 over a separate communication link.
[0024] The MDD 100 may also have a direct communication link 108 with the Media Delivery Service Provider 103 . Such a link might be a conventional 2400-baud modem connection to the Media Delivery Service Provider 103 . This communication link 108 may also be a direct hardwire connection or a network connection, such as an Ethernet connection.
[0025] In any event, the MDD 100 receives media content and data from a Media Delivery Service Provider 103 and delivers the media content and/or data to the media presentation device 101 for presentation to the customer. Typically, the MDD 100 can communicate in two-directions over the communication links 108 and 124 . That is, the MDD 100 can respond to queries and/or commands received from the Media Delivery Service Provider 103 and return data and for messages, in response to the receipt of a query or command. The Simple Network Management Protocol (SNMP) is a standard that has been developed to standardize such two-way communication between the MDD 100 and the Media Delivery Service Provider 103 . Typically, an SNMP agent will be installed in the MDD 100 and will coordinate all SNMP communications between the WD 100 and the Media Delivery Service Provider 103 . Applications operating on either servers within the Media Delivery Service Provider 103 , or within the Media Distribution Device 100 , may also communicate directly via TCP/IP or other proprietary protocol as appropriate for the applications needs. The specific protocol of communication is not material to the implementation of the invention. Notably, such two-way communications are not currently available over communications link 122 with the satellite 104 .
[0026] The Media Delivery Service Provider 103 may also use an exemplary embodiment of the present invention to upload software, media content, and/or data to the Media Distribution Device 100 or the media presentation device 101 . This upload can be automatic or in response to a customer request.
[0027] FIG. 2 is a block diagram depicting some of the primary components of an exemplary Media Distribution Device. The conventional Media Distribution Device 200 includes a processing unit 221 , a system memory 222 , and a system bus 223 that couples the system memory to the processing unit. The system memory 222 includes read-only memory (ROM) 224 , flash memory (not shown) and random access memory (RAM) 225 . A basic input/output system 226 (BIOS) contains rudimentary code to execute basic functions, such as system start-up. The BIOS 226 is stored in the ROM 224 . Various program modules may be stored in the RAM 225 . Such program modules might include an operating system 235 , a conditional access system software module 236 including a key 250 , and data and media content 238 .
[0028] Although not depicted in FIG. 2 , the MDD 200 could also include a hard drive, flash memory or other non-volatile memory for long-term storage of program modules such as billing information, the operating system 235 , the conditional access system 236 , and the data and media content 238 . The hard drive may be connected to the MDD 200 via a hard drive interface. Similarly, other peripheral devices could be connected to the MDD with other interfaces not depicted in FIG. 2 . Moreover, the MDD could also be equipped with an input device, such as keyboard and/or mouse.
[0029] The MDD 200 can also include a video adapter 248 or other adapter for delivery of media content and/or data to a media presentation device 247 . The MDD 200 also includes a Media In Adapter 246 and a Data In Adapter 253 . These adapters permit connection of the MDD 200 to a communication link for one-way and/or two-way communication with a Media Delivery Service Provider. The Media In Adapter 246 and the Data In Adapter 253 may incorporate a modem and/or other communication device.
[0030] The MDD 200 receives media content and data and makes the media content and data available to other internal components by way of internal interfaces such as the system bus 223 . The processing unit 221 can route the media content and/or data in accordance with the instructions of the operating system 235 and/or other applications executed in the RAM. 225 . In addition, the processing unit 221 may store the media content and data in the RAM 225 for subsequent use. The processing unit 221 may also direct the media content and/or data to the media presentation device 247 via the presentation device adapter 248 .
[0031] The conditional access system 236 may be executed by the processing unit 221 in response to a command received from the Media Delivery Service Provider or any other source. The command may be formatted in accordance with the SNMP protocol. The conditional access system 236 may also be executed in response to a command received from user input, such as a user selecting to view a pay-per-view event, for example.
[0032] FIG. 3 is a block diagram depicting a Media Delivery System with a software conditional access system that is an exemplary embodiment of the present invention. As described above in connection with FIG. 2 , the MDD 300 has a resident conditional access system 312 .
[0033] The Media Delivery Service Provider 302 is operative to communicate with the MDD 300 via the satellite 304 , a direct link 308 , and/or a DSL modem 306 . A broadband connection between the Media Delivery Service Provider 302 and the MDD 300 is preferable, because it permits the Media Delivery Service Provider 310 to communicate with the MDD 300 in real-time and can support an “always-on” connection. Thus, the Media Delivery Service Provider can query for and obtain information related to the MDD 300 within a very short time frame. Because a broadband connection can maintain an always-on status, the Media Delivery Service Provider can autonomously query the MDD 300 during off-peak hours of operation, thereby reducing the impact on system resources.
[0034] Although the broadband connection depicted in FIG. 3 is supported by means of an ADSL modem 306 , virtually any broadband technology can be used to implement an exemplary embodiment of the present invention. For example, a conventional broadband cable-T.V. connection between the Media Delivery Service Provider 302 and the MDD 300 can be used. Unfortunately, current broadband cable-
[0035] T.V. protocols are not as secure as an ADSL broadband communication link. Broadband cable-T.V. signals can be intercepted and deciphered, while the communication link between the ADSL modem 306 and the Media Delivery Service Provider 302 can be implemented as a Private Virtual Network that is not shared by other users. Thus, an ADSL broadband connection between the MDD 300 and the Media Delivery Service Provider 302 is preferred to other available broadband connections.
[0036] In different embodiments of the invention, the broadband connection 324 may be an xDSL connection, a Data Over Cable Service Interface Specifications (DOCSIS) cable modem connection, a residential gateway connected to an Ethernet port, an IEEE 802.11b (wireless) connection, a Bluetooth connection, or another well-known broadband connection,
[0037] In a preferred embodiment, the broadband connection 324 is an ADSL connection and the Media Distribution Device 300 and Media Delivery Service Provider 302 are connected via a permanent virtual circuit (PVC). Asymmetric Digital Subscriber Line (ADSL) is a high speed transmission technology originally developed by Bellcore and standardized by ANSI as T 1.413. ADSL typically uses existing unshielded twisted pair (UTP) copper wires from the telephone central office to the user's premises. ADSL modems may be used at the central office and the user's premises to transmit and receive information. A permanent virtual circuit (PVC), or Private Virtual Network (PVN), is a permanent association between two pieces of data equipment established by configuration. A PVC uses a fixed logical channel to maintain a permanent association between two pieces of equipment. Once defined and programmed by the carrier into the network routing logic, all data transmitted between any two points across the network follows a predetermined physical path, making use of a virtual circuit.
[0038] One of the advantages of using a PVC is that the Media Distribution Device may be identified based on the PVC. Thus, if the Media Distribution Device is moved to another location, then the service provider will know that it has been moved or cloned and will be able to take appropriate action, such as disconnecting service to prevent fraud.
[0039] In another embodiment of the invention, the Media Distribution Device is connected to a broadband infrastructure using a technology such as XDSL at the transport layer. Using a PVC managed by a device such as a Service Gateway, a secured connection is established over a private network to authenticate and authorize Media Distribution Device transactions. Applications may be loaded on the Media Distribution Device as an OSGi bundle. OSGi is the Open Services Gateway Initiative which is an independent, non-profit corporation working to define specifications for the delivery of multiple services over wide-area networks to local networks and devices. An OSGi specification defines an open framework that enables multiple software services to be loaded and run on a services gateway such as a Media Distribution Device, cable modem, DSL modem, PC or dedicated residential gateway. Media Distribution Devices can be authorized in a consumer network by a Residential Gateway (RG). The RG in this implementation becomes a physical layer security device.
[0040] In a CATV environment, an IPsec connection may be used rather than a PVC connection. IPsec is a secure version of the Internet Protocol (IP) that provides authentication and encryption at the packet level.
[0041] In one embodiment of the invention, the CAS 312 may be used as an access system to determine the media content that may be viewed. For example, a user who has purchased premium movie channels may have a CAS 312 downloaded to their Media Distribution Device. The CAS 312 may include one or more keys 326 that provide decryption for the premium channels, The keys 326 may also be downloaded to provide access to pay-per-view events and the like, The CAS 312 and keys 326 may be updated at any time by the Media Delivery Service Provider via the broadband connection 324 . The Media Distribution Device may also upload billing information to the Media Delivery Service Provider in real-time to prevent fraud.
[0042] Thus, as should be understood from the foregoing description, the present invention is a software-driven application that eliminates the cost of the hardware CAS and forces immediate billing of all services requested by a consumer on a broadband connected Media Distribution Device.
[0043] It should be understood from the foregoing description that the present invention provides greater security than the prior art because it is less likely to be able to hack the software as it was for the smartcards. Also, fixes and updates may be downloaded to the software CAS of the present invention. The present invention eliminates the smartcard required by the prior art, and the replacement of the smart card if conditional access is compromised.
[0044] FIG. 4 is a flow chart depicting an exemplary method for purchasing media services using a software conditional access system (CAS) in accordance with an embodiment of the present invention. It will be appreciated that the method of FIG. 4 is simply one embodiment of the present invention. Those skilled in the art will appreciate that the method may be used for other communication systems and may be modified to accommodate the various policies of communication system providers.
[0045] At step 400 , the method begins and a request for media services is sent to the Media Delivery Service Provider via a broadband connection at step 402 . For example, the request may be a request to view a pay-per-view event sent from a user's Media Distribution Device via a broadband connection after the user has selected to view the event using the Media Distribution Device or a remote control connected to the Media Distribution Device. A part of the request may be identifying information of the Media Distribution Device. For example, the MAC address of the Media Distribution Device or the hardware serial number of the Media Distribution Device may be sent with the request.
[0046] At step 404 , the Media Delivery Service Provider cross-references the identifying information with a user's account to determine whether to allow the user to 15 view the media service requested,
[0047] At step 406 , it is determined whether the identifying information matches a valid customer account and whether to allow the customer to view the requested program. If the Media Delivery Service Provider determines to allow the user to view the requested media service, the user's account (typically maintained by the service provider) is charged and a key is uploaded via the broadband connection to the Media Distribution Device at step 410 , Thus, there is no lag time between a user purchasing the media service and the user being charged for the media service. The key may be a software application that allows the user to view the requested media service. For example, the key may be software that is programmed to decrypt the requested media service for viewing. After the requested media service ends, after a predetermined amount of time, etc., the conditional access system of the Media Distribution Device may delete the key. For example, at step 412 , it is determined whether the time limit for the media service has expired and if so then the method proceeds to step 414 where the key is deleted and the method ends.
[0048] Referring back to step 406 , if the identifying information is rejected by the Media Delivery Service Provider, then a request for the customer to call a service representative is uploaded to the Media Distribution Device and displayed to the user at step 408 . The method then ends at step 499 .
[0049] Although the present invention has been described in connection with various exemplary embodiments, those of ordinary skill in the art will understand that many modifications can be made thereto within the scope of the claims that follow. Accordingly, it is not intended that the scope of the invention in any way be limited by the above description, but instead be determined entirely by reference to the claims that follow. | A method for purchasing a media service from a media delivery service provider includes sending a request to the media delivery service provider requesting the media service and authenticating a media distribution device by comparing a permanent virtual circuit established between the media distribution device and the media delivery service provider with a predetermined permanent virtual circuit defined and programmed by the media delivery service provider. Upon determining the media distribution device is successfully authenticated, the method includes downloading a software key from the media delivery service provider to the media distribution device and automatically deleting the software key after a predetermined amount of time. Upon determining the media distribution device is not successfully authenticated, the method includes downloading displayable data to the media distribution device from the media delivery service provider. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional Application No. 60/868,204, filed Dec. 1, 2006.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a print processing system, a printer, and a recording medium that can use plural print settings in one operation.
[0004] 2. Description of the Related Art
[0005] A printer driver, which is a program for causing a printing apparatus to operate, is provided in a computer. This printer driver has a function capable of not only converting data created by application software into a format for printing but also designating a printing method in the printing apparatus.
[0006] When a document created by the application software of the computer is printed in various different forms, it is necessary to change a print setting in the application software or the printer driver every time the printing is performed. In order to solve such complicated operation, techniques capable of using plural print setting are disclosed.
[0007] In a technique disclosed in JP-A-2002-14797, a presentation mode is prepared in print settings. When this mode is selected, it is possible to operate, at a time, printing for presentation of plural copies and printing with a layout changed for distribution of the plural copies.
[0008] Since the object of this technique is application to presentation, the technique is applicable to only a combination of a layout set during printing and a standard layout for presentation.
[0009] In a technique disclosed in JP-A-2004-70661, it is possible to check previews of plural print settings at a time. When plural previewed images are selected, results of the selection of the images are simultaneously printed.
[0010] In this technique, although it is possible to simultaneously perform printing according to the plural print settings, only one copy can be printed in each of the print settings.
BRIEF SUMMARY OF THE INVENTION
[0011] A recording medium according to a first aspect of the invention is a recording medium having recorded therein a print processing program for an information processing apparatus that exchanges information with a printing apparatus through a communication line and causes the printing apparatus to execute printing, the print processing program causing the information processing apparatus to execute: a first print-setting generating and storing step of generating and storing at least one first print setting via an input device connected to the information processing apparatus; a second print-setting acquiring step of acquiring at least one second print setting from the printing apparatus through the communication line; a third print-setting selecting step of urging a user to select at least one third print setting out of the stored first print setting and the acquired second print setting; a print-data converting step of converting a print command group issued by application software into respective print data in accordance with the selected respective third print settings; and a print-data transmitting step of transmitting the respective print data to the printing apparatus and causing the printing apparatus to print the print data.
[0012] A printing apparatus according to a second aspect of the present invention is a printing apparatus that exchanges information with an information processing apparatus through a communication line and executes a print operation, the printing apparatus comprising: a print-setting generating and storing unit that generates and stores at least one print setting; a print-setting transmitting unit that transmits the stored print setting to the information processing apparatus through the communication line according to a request from the information processing apparatus; and a printing unit that executes printing on the basis of print data transmitted from the information processing apparatus through the communication line.
[0013] A print processing system according to a third aspect of the present invention is a print processing system comprising: a printing apparatus; and an information processing apparatus that exchanges information with the printing apparatus and causes the printing apparatus to execute printing, the printing apparatus and the information processing apparatus being connected to each other through a communication line, wherein the information processing apparatus includes: a first print-setting generating and storing unit that generates and stores at least one first print setting via an input device connected to the information processing apparatus; a second print-setting acquiring unit that acquires at least one second print setting from the printing apparatus through the communication line; a third print-setting selecting unit that urges a user to select at least one third print setting out of the stored first print setting and the acquired second print setting; a print-data converting unit that converts a print command group issued by application software into respective print data in accordance with the selected respective third print settings; and a print-data transmitting unit that transmits the respective print data to the printing apparatus and causes the printing apparatus to print the print data, and the printing apparatus includes: a print-setting generating and storing unit that generates and stores at least one print setting; a print-setting transmitting unit that transmits the stored print setting to the information processing apparatus through the communication line according to a request from the information processing apparatus; and a printing unit that executes printing on the basis of the print data transmitted from the information processing apparatus through the communication line.
[0014] Additional objects and advantages of the invention will be set forth 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 obtained by means of the instrumentalities and combinations particularly pointed out hereinafter.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
[0015] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention, and together with the general description given above and the detailed description of the embodiments given below, serve to explain the principles of the invention.
[0016] FIG. 1 is a diagram schematically showing a structure of a print processing system according to an embodiment of the invention;
[0017] FIG. 2 is a flowchart showing a print setting procedure in which an administrator of a user inputs print setting data to an MFP;
[0018] FIG. 3 is a flowchart showing a print setting procedure in which a user of a PC performs print setting in the MFP;
[0019] FIG. 4 is a flowchart showing a procedure concerning print processing among the user, the PC, and the MFP;
[0020] FIG. 5 is a diagram showing a print screen;
[0021] FIG. 6 is a diagram showing a detailed display screen for individual setting;
[0022] FIG. 7 is a diagram showing the detailed display screen for individual setting;
[0023] FIG. 8 is a diagram showing a detailed display screen for uniform setting;
[0024] FIG. 9 is a flowchart showing a procedure concerning print processing among the user, PC, and the MFP;
[0025] FIG. 10 is a diagram showing a default setting screen; and
[0026] FIG. 11 is a flowchart showing a procedure concerning print processing among the user, the PC, and the MFP.
DETAILED DESCRIPTION OF THE INVENTION
[0027] FIG. 1 is a diagram schematically showing a structure of a print processing system according to an embodiment of the present invention. This print processing system includes personal computers (PCs) 1 and a multi function peripheral (MFP) 2 connected to each other through a communication line 3 .
[0028] In a form of this print processing system shown in the figure, for example, plural PCs 1 provided in an office share one MFP 2 . As the communication line 3 , a network such as a LAN can be used.
[0029] Each of the PCs 1 includes a PC main body 10 and an input and output device 11 . In the PC main body 10 , an input and output control unit 12 , application software 13 , a printer driver 14 , an individual setting file DB 15 , a uniform setting file DB 16 , and a program DB 17 are provided.
[0030] The input and output device 11 displays information transmitted from the PC main body 10 and inputs various instructions to the PC main body 10 . The input and output control unit 12 is an interface for carrying out exchange of various kinds of information between the MFP 2 connected to the communication line 3 and the input and output device 11 . The application software 13 and the printer driver 14 are programs that run under the management of an OS (not shown) of the PC 1 and realize a print processing method according to this embodiment.
[0031] In the individual setting file DB 15 , print setting data created by the PC 1 is stored. In the uniform setting file DB 16 , print setting data created by the MFP 2 is stored. In the program DB 17 , various programs running on the PC 1 is stored.
[0032] The MFP 2 includes an MFP main body 20 and a control panel 21 . In the MFP main body 20 , an input and output control unit 22 , a CPU 23 , a RAM 24 , and a ROM 25 are provided.
[0033] The control panel 21 displays information transmitted from the MFP main body 20 and inputs various instructions to the MFP main body 20 . The input and output control unit 22 is an interface for carrying out exchange of various kinds of information between the PC 1 connected to the communication line 3 and the control panel 21 . The CPU 23 collectively controls operations of the MFP 2 . In the RAM 24 , print setting data for the MFP 2 is stored. In the ROM 25 , various programs running on the MFP 2 are stored.
[0034] A print setting method is explained.
[0035] FIG. 2 is a flowchart showing a print setting procedure in which an administrator of a user inputs print setting data to the MFP 2 . Data set in this print setting is uniformly (commonly) used when the respective PCs 1 use the MFP 2 . Therefore, this setting is referred to as uniform setting.
[0036] In step S 01 , the administrator designates a uniform setting number and inputs print setting data from the control panel 21 . In step S 02 , the CPU 23 judges setting content.
[0037] When the setting content is designation of “color or monochrome”, in step S 03 , the CPU 23 executes color or monochrome setting processing. An original is printed in color or monochrome in accordance with this setting. When the setting content is “simplex or duplex”, in step S 04 , the CPU 23 executes simplex or duplex setting processing. Printing on one side of an original and printing on both sides of the original are controlled in accordance with this setting. When the setting content is designation of “N in 1”, in step S 05 , the CPU 23 executes N in 1 setting processing. N pieces of data are printed for one original in accordance with this setting. When the setting content is designation of a “company name”, in step S 06 , the CPU 23 executes company name setting processing. An inputted company name is printed in a predetermined position of an original in accordance with this setting. When the setting content is designation of an “identification name”, in step S 07 , the CPU 23 executes identification name setting processing. An inputted identification name is associated with the uniform setting number in accordance with this setting.
[0038] When “setting end” is inputted, in step S 08 , the CPU 23 stores the uniform setting number and the print setting data in the PAM 24 in association with each other. Items as objects of the uniform setting are not limited to the examples described above. For example, various functions of the MFP 2 can be adopted as setting object items.
[0039] FIG. 3 is a flowchart showing a print setting procedure in which a user of the PC 1 performs print setting in the MFP 2 . Data set in this print setting is individually used when the respective PCs 1 use this MFP 2 . Therefore, this setting is referred to as individual setting.
[0040] In step S 11 , the user designates an individual setting number and inputs print setting data from the input and output device 11 . In step S 12 , the application software 13 that executes setting processing judges setting content.
[0041] When the setting content is designation of “color or monochrome”, in step S 13 , the application software 13 executes color or monochrome setting processing. An original is printed in color or monochrome in accordance with this setting. When the setting content is designation of a “print quality”, in step S 14 , the application software 13 executes print quality setting processing. High definition printing and normal definition printing on the original are controlled according to this setting. When the setting content is designation of “N in 1”, in step S 15 , the application software 13 executes N in 1 setting processing. N pieces of data are printed on one original.
[0042] When “setting end” is inputted, in step S 18 , the application software 13 stores the individual setting number and the print setting data in the individual setting file DB 15 in association with each other. As a result, individual setting data corresponding to the individual setting number is stored in the individual setting file DB 15 . Items as objects of the individual setting are not limited to the examples described above. For example, the uniform setting data can be adopted as a setting item and various functions of the MFP 2 can be adopted as setting object items.
[0043] In order to cope with a case in which the individual setting is not performed, default setting data set in advance is stored in the individual setting file DB 15 .
[0044] FIG. 4 is a flowchart showing a procedure concerning print processing among the user, the PC, and the MFP. In the PC 1 , the printer driver 14 handles the print processing according to this embodiment.
[0045] In step S 31 , for example, the user designates an image file and instructs printing of the image file from the input and output device 11 . In step S 32 , the printer driver 14 that has received the print instruction transmits a signal for requesting uniform setting data to the MFP 2 .
[0046] In step S 33 , the CPU 23 searches through the RAM 24 to check whether the uniform setting data is stored therein. When the uniform setting data is stored, the CPU 23 transmits the uniform setting data to the PC 1 .
[0047] In step S 34 , the printer driver 14 stores the transmitted uniform setting data in the uniform setting file DB 16 in the PC and searches through the individual setting file DB 15 to check whether individual setting data is stored. In step S 35 , the printer driver 14 generates a setting screen. In step S 36 , the printer driver 14 displays the setting screen on the input and output device 11 as a print screen.
[0048] FIG. 5 is a diagram showing a print screen 30 . In the print screen 30 , together with display of a name for each print setting, number-of-print-copies input sections 30 a , setting-value display buttons 30 b , a print start button 30 c , and a cancel button 30 d are provided. In an example shown in FIG. 5 , two individual setting files, two uniform setting files, and one default setting file are displayed.
[0049] The number of copies for each print setting is set in each of the number-of-print-copies input sections 30 a . When 0 is set in this section, printing based on the print setting is not performed. When the user operates one of the setting-value display buttons 30 b , detailed data of the print setting can be displayed. The user can change this detailed data. When the user operates the print start button 30 c , a print operation is executed in accordance with content of the print screen 30 . When the user operates the cancel button 30 d , the print processing is finished.
[0050] FIG. 6 is a diagram showing a detailed display screen 31 for individual setting 1. In the detailed display screen 31 , setting-value operation buttons 31 a , setting-value display buttons 31 b , a print start button 31 c , and a cancel button 31 d are provided.
[0051] In each of the setting-value operation buttons 31 a , a value set for each setting item is displayed. Contents displayed in the buttons in a dark color are values presently set. When the user operates the buttons of a light color, the color of the operated button changes to a dark color. This indicates that the setting is changed to a value displayed on the button.
[0052] When the user operates one of the setting-value display buttons 31 b , more detailed content of the print item is displayed. The user can further change the displayed content.
[0053] For example, when the user operates the setting-value display button 31 b corresponding to a print setting item “duplex”, plural forms with different directions of printing on both sides of a sheet are displayed. The user can select a desired form out of the forms.
[0054] When the user operates the setting-value display button 31 b corresponding to a print setting item “staple”, plural forms with different positions where a staple is provided are displayed. The user can select a desired form out of the forms. In the setting-value operation button 31 a corresponding to “staple” in FIG. 6 , “No” is selected. Therefore, the setting-value display button 31 b corresponding to “staple” is displayed in a light color. This indicates that the setting-value display button 31 b cannot be operated.
[0055] When the user inputs characters in the setting-value operation button 31 a corresponding to a print setting item “header setting”, the inputted characters can be printed in a header. When the user operates the setting-value display button 31 b corresponding to the print setting item “header setting”, a position of the characters printed in the header can be designated.
[0056] When the user operates the print start button 31 c , a print operation is executed in accordance with displays on the print screen 30 and the detail display screen 31 . When the user operates the cancel button 30 d , the print processing is finished.
[0057] In FIG. 6 , a print setting in printing an in-house document for employees is shown. Therefore, 2 in 1 in duplex monochrome printing is set to reduce cost as much as possible.
[0058] FIG. 7 is a diagram showing a detailed display screen 32 for individual setting 2. The structure of this detailed display screen 32 is the same as that of the detailed display screen 31 shown in FIG. 5 . Thus, detailed explanation of the structure of the detailed display screen 32 is omitted. In FIG. 7 , a print setting in printing an in-house document for executives is shown. Therefore, although 2 in 1 in duplex printing is set to reduce cost as much as possible, color printing is set to make the material legible.
[0059] FIG. 8 is a diagram showing a detailed display screen 33 for uniform setting 2. The structure of the detailed display screen 33 is the same as that of the detailed display screen 31 shown in FIG. 5 . Thus, detailed explanation of the structure of the detailed display screen 33 is omitted. In FIG. 8 , a print setting in printing a document submitted to a customer is shown. Therefore, simplex printing and color printing are set to make the entire document legible. Moreover, an indication that the document is a material for a customer is printed on a header.
[0060] In a detailed screen concerning uniform setting, print items that can be changed are limited. This is for the purpose of preventing a value set by the administrator of the MFP 2 from being arbitrarily changed on the PC side. Therefore, setting items, a change of which is limited, are only displayed and cannot be changed. For example, processing such as gray-out is applied to the setting items.
[0061] Referring back to FIG. 4 , in step S 37 , the user sets the number of copies of a document, which the user desires to print from the print screen 30 , in one of the number-of-pint-copies input sections 30 a . In step S 38 , the user depresses the print start button 30 c . Then, in step S 39 , the printer driver 14 converts a print processing command from the application software 13 into print data on the basis of setting content on the print screen 30 .
[0062] In this conversion, uniform setting data and individual setting data corresponding to a selected print setting are referred to. Even when the user changes and uses the uniform setting data, the changed uniform setting data is effective only in the print processing. Therefore, when other image files are printed or when the other PCs perform printing, the change of the data does not affect the printing.
[0063] In step S 40 , the printer driver 14 transmits the generated print data to the MFP 2 . In step S 41 , the printer driver 14 displays an indication that the print processing is finished on the input and output device 11 .
[0064] In step S 42 , the MFP 2 performs preparation for controlling a print operation on the basis of the transmitted print data. In step S 43 , the MFP 2 executes printing. In step S 44 , the user can acquire a print generated in this way.
[0065] [First Variation]
[0066] Print processing at the time when uniform setting and individual setting are not performed is explained.
[0067] FIG. 9 is a flowchart showing a procedure concerning print processing among the user, the PC, and the MFP. In the PC 1 , the printer driver 14 handles the print processing according to this embodiment.
[0068] In step S 51 , the user designates an image file and instructs printing of the image file from the input and output device 11 . In step S 52 , the printer driver 14 that has received the print instruction transmits a signal for requesting uniform setting data to the MFP 2 .
[0069] In step S 53 , the CPU 23 searches through the RAM 24 to check whether the uniform setting data is stored therein. When the uniform setting data is not stored, in step S 53 , the CPU 23 transmits an indication that the uniform setting data is not present to the PC 1 .
[0070] In step S 54 , the printer driver 14 searches through the individual setting file DB 15 to check whether individual setting data is stored therein. When only default setting data is stored, in step S 55 , the printer driver 14 generates a default setting screen. In step S 56 , the printer driver 14 displays the default setting screen on the input and output device 11 . This default setting screen is displayed instead of the print screen shown in FIG. 5 .
[0071] FIG. 10 is a diagram showing a default setting screen 34 . The default setting screen 34 has the structure same as that of the detailed display screen 31 shown in FIG. 6 except that a number-of-print-copies input section 34 a for setting the number of print copies is provided. Therefore, detailed explanation of the default setting screen 34 is omitted.
[0072] A procedure in steps S 57 to S 64 for executing printing on the basis of the default setting screen 34 is the same as the procedure in steps S 37 to S 44 shown in FIG. 4 . Thus, detailed explanation of the procedure is omitted.
[0073] [Second Variation]
[0074] In the embodiments described above, uniform setting can be performed only on the MFP 2 side. However, in a form of a second variation, uniform setting can be performed in the PC 1 .
[0075] FIG. 11 is a flowchart showing a procedure concerning print processing among the user, the PC, and the MFP. In the PC 1 , the printer driver 14 handles print processing according to this embodiment.
[0076] In step S 71 , the user inputs an instruction for executing uniform setting from the input and output device 11 . In step S 72 , the printer driver 14 that has received the uniform setting instruction transmits a signal for requesting a template for the uniform setting to the MFP 2 .
[0077] In step S 73 , the CPU 23 transmits the template for uniform setting to the PC 1 . Setting items that the PC 1 may be allowed to set are described in the template to be transmitted. In other words, items that are judged as inappropriate to allow the user to set are not described in the template to be transmitted. Alternatively, it is also possible that items are described in the template but cannot be operated.
[0078] In step S 74 , the printer driver 14 generates a setting screen on the basis of the transmitted template and displays the setting screen on the input and output device 11 . The user inputs a setting value from the input and output device 11 using this setting screen. When the user decides the setting input, in step S 76 , the printer driver 14 updates the template on the basis of the inputted set value. In step S 77 , the printer driver 14 transmits setting data to the MFP 2 .
[0079] The MFP 2 creates a uniform setting file on the basis of the setting data transmitted by the CPU 23 and stores the uniform setting file in the RAM 24 .
[0080] [Third Variation]
[0081] In the embodiments described above, the operations of the print processing system including the plural PCs and the one MFP are explained. In a form of a third variation, a print processing system includes plural PCs and plural MFPs.
[0082] With such a structure, in signal transmission and reception operations between the PCs and MFPs, a cooperative operation of the MFPs can be realized in addition to the operations described above. In other words, efficient print processing can be performed by allocating, with one of the plural MFPs set as a core machine, jobs to the other MFPs.
[0083] For example, it is also possible to transfer print data to specific MFPs to cause the MFPs to handle color printing and duplex printing, respectively. It is also possible to transfer, when one MFP has broken down, print data to the other MFPs such that the other MFPs can succeed and execute jobs.
[0084] According to the embodiments explained above, the effects described below can be realized.
[0000] 1. The “individual setting” function is provided and the mechanism that can store and use a setting is introduced. Consequently, the user can prepare plural settings in advance.
2. The “uniform setting” function is provided and the mechanism that can perform the uniform setting from the MFP and store the setting in the MFP is introduced. Consequently, common printing can be performed among people who use the MFP. The user can use the uniform setting without performing special setting.
3. The “uniform setting” function can be set from the outside of the MFP.
[0085] 4. The “individual setting” function and the “uniform setting” function can be used with a part of the functions changed. Therefore, a setting value can be flexibly used.
5. The “individual setting” function and the “uniform setting” function can be selected with simple operation. Therefore, simultaneous printing employing plural settings can be realized with simple operation.
[0086] The functions explained in the embodiments can be realized not only by using hardware but also by causing, using software, a computer to read a program that describes the functions. One of the software and the hardware may be appropriately selected to realize the functions.
[0087] Moreover, it is possible to realize the functions by causing the computer to read a program stored in a not-shown storage medium. The storage medium according to the embodiments may take any storage form as long as the storage medium can store the program and is a computer readable storage medium.
[0088] Additional advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details and representative embodiments shown and described herein. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents. | A recording medium having recorded therein a program for an information processing apparatus that exchanges information with a printing apparatus and causes the printing apparatus to execute printing, the program causes the information processing apparatus to execute a first print-setting generating and storing step of generating and storing at least one first print setting, a second print-setting acquiring step of acquiring at least one second print setting from the printing apparatus, a third print-setting selecting step of urging a user to select at least one third print setting out of the first print setting and the second print setting, a print-data converting step of converting a print command group issued by application software into respective print data in accordance with the respective third print settings, and a print-data transmitting step of transmitting the respective print data to the printing apparatus and causing the printing apparatus to print the print data. | 6 |
BACKGROUND OF THE INVENTION
This invention relates generally to
(a) a method for heating a hydrocarbon-containing subterranean formation to develop a zone containing carbonized material in the pore spaces and
(b) the mineral formation containing carbonized material in the pore spaces resulting from the heating process.
More particularly, the invention relates to a method for creating a carbonaceous current-carrying deposit in a formation surrounding a borehole, and to the enlarged-radius electrode thus formed from the deposit. A borehole that is completed as a well and having appropriate electrical features so that it can function as an electrode in contact with the adjacent formation is known as an electrode well. The utility of the invention lies in the heating, by electrical means, of a subterranean formation, between two or more boreholes, as the step following the formation of the carbonaceous electrode.
Broadly, when an electrical current is used in a subterranean formation to heat the formation, it is desirable to have an electrode of substantial size. If small electrodes are used, a high current density develops, which leads to a high temperature in the vicinity of the electrode. This high temperature vaporizes or flashes the connate brine or water, with said flashing effectively removing some of the electrolyte present, thus reducing the conductivity and even leading to an interruption of the process. The flash temperature depends on the depth of the electrode and, broadly, can vary from about 220° to about 600° F. (104°-315° C.). In an effort to overcome the problem of flashing, and thus the reduction in electrical conductivity, previous schemes have suggested injecting metal or graphite particles into the formation to keep the current path open and reduce the current density, thus delaying the onset of the flashing phenomenon. U.S. Pat. No. 3,848,671 (Kern) concerns a method of producing bitumen in which injection and production wells are completed, and the formation is heated by passing electricity between electrodes positioned in each well. As mentioned above, the Kern process has the limitation that during heating, the temperature immediately adjacent the wells must not be so high as to cause evaporation of the water envelopes, at the pressure found in the formation. U.S. Pat. No. 3,958,636 (Perkins) produces bitumen from a tar sand formation while heating the formation by electrical conduction between a plurality of wells. A high back pressure is maintained on the wells and an immiscible fluid is injected into the formation through one of the wells. However, like the above Kern patent, Perkins discloses that during heating, the temperature in the regions of highest current densities, that is, in the regions immediately about and adjoining the wells, should not be so high as to cause evaporation of the water envelopes at the pressure that is sustainable by the overburden. This means that the electrical current should be maintained low enough to prevent drying of the tar sand formation around the wells. U.S. Pat. No. 3,931,856 (Barnes) increases the "size" of the electrode used in heating by providing a larger area of high electrical conductivity. This is done by having an electrode well adjacent a satellite well. Preliminary heating of the formation between these wells mobilizes the viscous oil, and it is removed. Then, water containing an electrolyte is circulated between the electrode and satellite wells, effectively increasing the "size". U.S. Pat. No. 3,874,450 (Kern) enlarges an electrode by having an upper section of conductive casing in a vertical wellbore with a lower section of nonconductive casing. The bottom of the wellbore has a deviated section extending laterally from the vertical axis of the bore in a predetermined direction. This deviated section contains an electrode and is filled with electrolyte. When electricity is applied to the wellbore, current flows between the upper section and the deviated section, thus heating the formation over a larger volume than is possible by prior methods. This deviation operation necessitates additional drilling variables and complicates the wellbore completion, resulting in additional expense. The Kern '671 and Perkins methods are careful to point out that, during formation heating, the temperatures adjacent the electrode wells must not be so high as to cause evaporation of the water envelopes.
SUMMARY OF THE INVENTION
My invention concerns a method for creating an electrode of enlarged effective radius, for further use in a process involving the use of electric currents to heat a subterranean, hydrocarbon-bearing formation. Heating of the formation improves the recovery of hydrocarbons through mechanisms such as viscosity reduction or hydrate decomposition.
My invention comprises a process for creating an effective electrode of enlarged radius, said electrode being a carbonaceous, current-carrying deposit, in a subterranean, hydrocarbon-bearing formation surrounding the electrode, having the serial steps of:
(a) forming a borehole in the hydrocarbon-bearing formation,
(b) placing a heating device in said borehole,
(c) energizing the device to heat the surrounding formation to a temperature high enough to produce coking of at least a portion of the hydrocarbon-bearing formation, and
(d) maintaining the temperature of step (c) for a length of time to obtain the current-carrying electrode of desired radius.
The invention also comprises the electrode of enlarged effective radius resulting from the above-described process.
During the coking step of the process, any water present is vaporized. Similarly, the light ends of the hydrocarbonaceous formation are vaporized. After the vaporized water and light ends are removed, heating is continued until extensive thermal cracking of the hydrocarbon portion of the formation occurs, with the resultant production of coke or coke-like material. As a result, the formation surrounding the borehole becomes more permeable. This permeability can be utilized later when an electrolyte solution is injected into the electrode. The enlarged effective electrode resulting from the above-mentioned steps is now appreciably larger than the original borehole and can be energized to heat the surrounding formation. If desired, concentrated electrolyte, such as brine, can be injected into the permeable deposit to assist in the later operation of the current-carrying electrode. When this process, involving the formation of a borehole and the creation of a carbonaceous, current-carrying electrode, is repeated in a second borehole spaced apart from the first borehole, it is possible to enlarge the effective radii or diameters of the respective borehole electrodes so that, when current is passed through such a formation between the two electrodes, the mid-point temperature of the formation (which is the minimum temperature between the electrodes) is increased to where the hydrocarbon portion of the formation becomes mobile. This mobile material can then be displaced from the formation by injecting a drive fluid.
DESCRIPTION OF THE DRAWINGS
FIG. I shows a cross-section view of a borehole at the initiation of the coking process.
FIG.II shows a cross-section view of the borehole at the end of the coke-producing process.
FIG. III shows an embodiment of the completed invention, a cross-section view of two electrode wells, each having an enlarged effective radius.
FIGS. IV (a, b, c, d) show the temperature in the tar sand formation at varying distances from the outer edge of the borehole after the heater is activated, assuming a diameter of two feet for the borehole and associated heater. FIG. IVa shows how the formation is heated, at varying distances and over varying times, when the electric heater maintains a temperature of 800° F. (426° C.) FIGS. IVb, c, and d are similar graphs showing formation temperature when the heating device maintains temperatures of 1000°, 1200°, and 1500° F. (538°, 649°, 815° C.), respectively.
The drawings are not in proportion.
DETAILED DESCRIPTION OF THE INVENTION
The process of creating an electrode of enlarged radius can be carried out in a number of underground formations. Since the process involves coking of a hydrocarbon-bearing formation, it is evident that the formation must contain material that can be transformed into coke or a coke-like material. This coke-like material is carbonaceous in substance and typically has a permeability greater than that of the original formation. Underground formations that are amenable to the purpose of this invention are those comprising tar sand, oil shale, and heavy oil deposits, such as those found in Canada and in the Orinoco Basin.
One embodiment of the invention is noted in FIG. I, which shows the borehole at the initiation of the coking process. For this embodiment, a tar sand formation 1 is shown as the underground formation. Borehole 2 is drilled from surface 3 through overburden 4 and through the tar sand formation 1 at least partially into the underlying formation 5. The details of drilling a borehole are well-known and need not be discussed here. After the borehole has been drilled, suitable casing 6 is set in the overburden and cemented 7 in place, leaving the open borehole 8 in tar sand formation 1 uncased, since the invention is directed toward the formation of an electrode of a large effective radius in a hydrocarbon-bearing formation. Then, as is well known in the petroleum industry, a downhole heating device, exemplified by an electric heater 9, is placed in the open borehole 8 of tar sand formation 1. Heating device 9 is connected to and suspended from surface 3 by tool cable 10. Heating device 9 is also connected to a source of power (not shown on surface 3) by an electrical cable 11, comprising power supply wires, temperature control wires, and other necessary electrical fittings.
The heating device used in the process can be any of a variety of such devices. Although an electric heater is shown in FIG. 1, a down-hole combustion device, such as a propane burner, can be used to heat the surrounding formation. Other possible heating devices include those using the thermite process or a nuclear device. The size, shape, and type of device used is not critical, as long as a sufficient and controlled supply of heat energy can be applied to the formation surrounding the borehole. The heating device is placed in that portion of the formation where the ultimately-formed electrode is desired. Since these devices are subject to high temperatures, with resultant stress and corrosion, the devices are usually used for forming one electrode and are then discarded.
In prior methods using electrical heating of an underground formation, the presence of connate water in the formation has been noted. These prior processes are controlled so that the connate water is not heated to a temperature which will cause disappearance of the water, such as vaporization. The loss of such water in the formation renders the formation appreciably non-conductive, thereby reducing the utility of the resistance heating process.
On the other hand, in the present process, a heating device is controlled at a temperature such that thermal cracking occurs in at least a portion of the hydrocarbon-bearing formation surrounding the heating device. As a consequence of this cracking temperature, nearby formation water is vaporized, and products of thermal cracking, such as light ends, are produced. These vapors and gases can be removed, if necessary, through the borehole. Particles of coke, or thermocracked carbonaceous material, are produced by these high temperatures, typically greater than 500° F. (260° C.) Porosity is developed in the coke, so that the particles allow the inflow of brine. Thus the coked portion, containing brine, has improved characteristics as an electrode. This carbonaceous, current-carrying electrode is formed in place and retains many of the chemical and physical properties of the original formation.
FIG. II represents the formation surrounding heating device 9 at the end of the coke-producing process. The coked zone 12 is substantially cylindrical in shape, generally following the shape of the heating device. This coked zone 12 can be considered the raw material for, or the precursor of, the effective electrode of enlarged radius which is used in a subsequent operation for electrically heating a larger portion of the formation.
There are many variables that enter into the process of the invention, such as the geology of the hydrocarbon-bearing formation, the thickness of the formation, the temperature and time necessary for cracking the hydrocarbon-bearing portion, and the ultimate effective radius of the electrode to be formed. The radius of the original borehole, and thus the radius of the heating device, can vary from about 2 inches (5 cm) to about 2 feet (61 cm). The radius of the electrode produced as a result of the process can vary from about 2 feet (61 cm) to about 10 feet (305 cm). The temperature of the heating device should be at least about 800° F. (426° C.), preferably in the range of 1,000°-1,500° F. (538°-815°), and the time necessary to produce an electrode of the desired radius can vary from about 1 to about 12 months.
These time-temperature-radius factors are related as shown in FIG. IV. These graphs show how effectively the heater in the borehole, at a given temperature, transmits heat to the surrounding formation over varying periods of time. The graphs are based on data for heat transference through an idealized formation, assuming a borehole (and heater) of 2 feet diameter. Therefore the graphs are meant to show approximate parameters. For example, from FIG. IVa, if the borehole heater is maintained at 800° F. (426° C.), after 100 days, the formation temperature 5 feet from the center of the borehole (or 4 feet from the outside of the heater) is about 300° F. (149° C.). If it is assumed that substantial coking of the formation takes place above about 500° F. (260° C.), FIG. IVa indicates that this temperature is reached at a distance of about 2.5 feet from the center of the borehole after about 1 year of heating. On the other hand, if the heater is at 1000° F. (538° C.) (FIG. IVb) for about 1 year, this coked zone (temperature of about 500° F. (260° C.)) radius is about 4 feet. From FIG. a zone radius of about 4 feet is reached after about 100-120 days when the heater is about 1200° F. (649° C.). And a heater temperature of about 1500° F. (815° C.) (FIG. IVd) maintained for about 1 year results in a formation temperature of about 500° F. (260° C.) about 7.6-7.8 feet from the center of the borehole.
These graphs are used as guides for the formation of electrodes of varying sizes.
FIG. III shows a cross-section of two completed wells, wherein sufficient work has been done on the boreholes to carry out a subsequent heating operation. Tubing strings 13, connected to a proper power source (not shown), are inserted into the boreholes and separated by packing devices from casings 6 and the formation 1. Further, electrical insulating sections 15 are used to insulate the lower metallic portion of each borehole fitting from each casing 6.
Sand screens 16 are inserted, by means well known in the petroleum industry, in the lower portion of each borehole to provide ingress and egress of liquids and vapors between formation 1 and the borehole. Insulating oil 17 is added to the upper portion of each borehole to insulate the charged tubing string 13 from casing 6 and surrounding overburden 4. To provide good electrical contact with formation 1 and to act as a coolant, an electrolyte 18 such as brine, can be forced down each inner tubing string and returned to the surface through each outer tubing string. Some electrolyte flows through the openings of sand screens 16 and enters coked zones 12. Then, during a subsequent process, when electric energy is applied to the lower portion of each borehole, each coked zone 12 becomes an effective electrode of enlarged radius.
Coked zone 12 has a degree of porosity and permeability related to the original formation. Coke particles (or carbonaceous particles) formed by the in-situ heating of the tar sand are distributed in the pores of the formation, and these particles partially fill the pores. Generally, the pores are connected so that there is a continuous path for the conduction of electricity. | The electrode of an electrode well is formed by inserting a heating device into the borehole and heating the surrounding formation to a temperature at which the hydrocarbon-containing material undergoes thermal cracking, resulting in a coke-like residue surrounding the heater. This conductive and permeable carbonized material serves as an electrode of enlarged radius for further electroheating of the formation. | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation-in-part of U.S. application Ser. No. 12/103,808 filed Apr. 16, 2008, said application is a non-provisional application claiming the benefit of provisional Patent Application Ser. No. 60/912,221 filed Apr. 17, 2007 the disclosures of aforesaid applications are incorporated by reference in their entirety herein.
BACKGROUND OF INVENTION
[0002] 1. Field of Invention
[0003] This invention relates generally to methods of providing on-line retail experiences and, more particularly, to on-line interfaces, which provide follow on on-line retail experiences related to the original purchase.
[0004] 2. Background Art
[0005] There are various on-line retail experiences available to consumers on wide area networks (WAN) such as for example on the internet. Many consumers perform various retail transactions via the internet. For example, consumers have the ability to visit via the internet the web site or URL of a retailer. A consumer, while browsing the web site, can place an order purchasing various items made available. Often the items purchased can be ordered with various options. For example, if a consumer is ordering a personal computer on-line, the consumer may be prompted to select from various optional features to semi-customize the computer to the customers specifications within certain optional constraints. For example, a consumer may select a random access memory (RAM) capacity option of 1 gigabyte or 2 gigabytes. The same may apply for purchasing clothing apparel having various optional colors, sizes and features. The same may apply for toys and other items.
[0006] In addition, on-line retail experiences may allow consumers to modify or cancel an order or view the fulfillment status of an existing order. On-line experiences may also allow you to revisit the web site where the item was purchased and purchase additional accessory items to add to the originally purchased item. For example, if a computer is purchased without a DVD formatted disc drive then a consumer can revisit the site to purchase a DVD drive for which the consumer can install or have installed.
[0007] Toys are also available for purchase via an on-line retail experience. For example, various categories of dolls can be purchased on-line and the on-line experience may allow the user to select from among various options for each category of doll including skin color, eye color and hair color. Also, the on-line experience may allow the consumer to purchase various accessories for the doll. As an alternative, a consumer may visit the physical retail store and purchase one of various categories of dolls and later visit the web site of the retail store or the actual physical retail store and purchase additional accessory items that are compatible with the original purchase.
[0008] Once a consumer has visited a web site and purchased one or more items, it is typical for the on-line interface to prompt the user to register for a billing account and/or register to receive various electronic mail notices relating to promotions, general information and special offers. Registration may also allow for identification with previous purchases.
[0009] There are various on-line retail experiences and various physical in-store retail experiences that allow a consumer to semi-customize a purchase item, for example a toy, and revisit later either on-line or at the physical store to purchase accessory items for the previous purchase or purchase a new item from a different category. However, there isn't a continuation of or a direct correlation to the original purchase experience. There is no direct correlation between the identity of each individual consumer, their original purchase experience, the specification of the originally purchased item; and the later on-line or physical retail experience. The customized toy purchased is not provided with an identifier specifically identifying its features and the customer/purchaser, such that the consumer experience with the newly purchased customized toy can be continued. The original purchase experience is not memorialized in a way that the experience can be continued and revisited. Therefore, a better on-line experience is needed that addresses the above short comings.
BRIEF SUMMARY OF INVENTION
[0010] The invention is a method for continuing the purchase experience of a personalized semi-custom toy in a follow-up on-line interface experience or in a physical retail experience. The method includes the steps of a consumer assembling a semi-custom toy configuration by selecting from among multiple major component styles and assembling the major component styles selected and selecting additional optional accessories to add to the major components resulting in a semi-custom toy configuration; the consumer inputting identifiers for the selected major component styles and accessories so that an over all toy identifier can be assigned, which is associated with and correlates to the resulting configuration; the consumer selecting a personalized name, or nickname to be assigned to the resulting toy configuration; memorializing the information electronically into a consumer/toy-configuration profile stored in a database having electronic memory for future retrieval and manipulation; and recalling the consumer/toy-configuration profile to continue the original purchase experience. The toy identifier can be an alphanumeric data string having encoded therein as part of the string—body chassis styles, date purchased, member number and etc. . . .
[0011] For example this method could be implemented for a modular custom toy vehicle. When a consumer enters a retail space, the consumer, if desirous of purchasing a custom vehicle can be directed by way of retail space layout and/or a customer service representative to a toy vehicle body selection station including a display rack having segregated display channels for displaying vehicle body styles contained in packaging, which can be on major component. At this station the consumer can view the various body styles and select a body style.
[0012] The consumer can transport the selected body style to a template sampling station. The sampling station can include a template toy vehicle chassis that has outer dimensions substantially the same as an actual mating toy vehicle chassis for test fitting a selected body. The consumer can place their selected body style over the template in order to get a better visualization of the appearance of the final product. Multiple chassis template styles can be provided that correspond to the various actual chassis styles. For example, there can be a street chassis design (gives the appearance of a standard car chassis) and an off-road chassis design (gives the appearance of an off-road vehicle or raised truck chassis). The chassis can be the second major component.
[0013] The consumer can go to a sound module station. The sound module station can include electronically integrated sub systems including a built in speaker system, an electronic storage and playback system for storing and playing back sound clips. The station can also include a selection interface for receiving consumer selections to sample sound clips and corresponding drawers containing sound modules. The selection interface can comprise multiple selection mechanisms, such as for example, buttons that are electronically actuated when depressed. The buttons can be numbered to correspond to stored sound clips. When a button is depressed, the playback system can audibly playback the sound clip through the built in speaker system. The consumer can retrieve a selected sound module from the drawer containing the modules.
[0014] The sound module can have a programmable electronic storage medium and controller function. The controller function can be operable to control receipt and storage of sound data and other electronic data for initiation of electronic animation. The data can be stored to the electronic storage medium and a controller can control transmission of data from the module to other peripheral systems. Receipt of the sound data can be through a first connector interfaceable with a personal computing system and where transmission of sound data can be through a second connector interfaceable with said sound module receptacle of the toy vehicle or there can be a single connector for both functions. This feature can allow the purchaser to later continue their purchase experience by purchasing different sound modules containing different control data or sound data so that the sound playback or the animations can be varied.
[0015] The toy assembly can be such that the electrical housing portion, which can be adapted to receive the sound module and can be part of a chassis of toy vehicle and/or can be housed with an externally mounted or connected or otherwise associated accessory, such as for example, a toy trailer. The accessory can have a receptacle connector for the sound module similar to that of the chassis of the toy vehicle. The accessory can also have its own power source and speaker system. The accessory can include multiple receptacles for multiple types of sound modules and connectors. The accessory can also have an audio output, such as for example, for a headphone jack. The accessory can also have other interfaces and/or connections for other types of audio electronic systems. The accessory can also have an interface to a personal computing device as well as an interface to the toy assembly. These interfaces can allow the user to access on-line games and other activities to while interfacing with the toy assembly real time to thereby initiate certain toy assembly animations responsive to the on-line game or activity being conducted.
[0016] The accessory can have a controller function that is operable to control receipt and storage of sound data and can be operable to interface with the personal computing system to download audio sound clips stored on the personal computing. The data stored on the module can include data other than audio sound data, such as for example other electronic animation control data such as data to control flashing of lights.
[0017] The process can include the steps using a personal computing device, such as for example, a personal computer (PC), personal data assistant (PDA) or other like computing device to connect to a local or wide area network (LAN or WAN), such as for example, the internet, to access remotely stored audio sound files and/or data files and to download the files to the personal computing device. Alternatively, a game or activity can be played using the Avatar of the toy assembly. For example, a provider of audio sound clips and/or data files particular designed to function with a given toy design can provide a web site that can be accessed by the toy owner. The web site can provide a functional interface that allows the owner to navigate to, sample, and select files for download. Once selected, the owner can download the file to their personal computing device. Once downloaded the process can include the step of communicably connecting the sound module to the personal computing device by way of a standard interface connector, such as for example, a USB connector.
[0018] The sound module can have a controller function, implemented in circuitry and/or firmware, that can communicate with the personal computing device for the purpose of uploading the previously downloaded file to the sound module. The control function can also control the transmission of the data file from the sound module through the connector. The sound module containing an electronically stored audio sound and/or other category of data file can be communicably connected to the toy receptacle. The toy can then access the file on demand. Optionally the owner of the toy can also purchased multiple preprogrammed sound modules that are read only or reprogrammable. The owner can also purchase blank sound modules with upload capability.
[0019] Once installed in the receptacle of the toy, the toy can access one or more data files stored on the sound module. The data files can be merely audio files that are stored on the sound module and the toy has a control function to access the data and play back the audio sound clip. Alternatively the data files can include audio files as well as other corresponding control data that the toy controller can access for controlling other toy functions, such as for example, toy lighting and/or movement.
[0020] One embodiment of the present invention can include a toy assembly having a data module receptacle with an external facing access port and connector where said data module receptacle connector is communicable with an on-board controller and sound playback system and/or other animation systems. The data module can also include a programmable electronic storage medium, where the on-board controller function is operable to communicate with the data module through the connector when the data module is connected to the data module receptacle connector. The controller function can be operable to control receipt and storage of sound data and other electronic data for initiation of electronic animation. The controller function can retrieve data from the data module and control on-board operations based on the data retrieved. For example, the controller function can retrieve sound clip data and transmit the sound clip data to a play back system for audio playback.
[0021] This embodiment can also include an accessory module also having an accessory receptacle with an accessory connector communicable with an on-board accessory controller. The accessory controller can also be communicable with an external computer interface connector, such as for example a standard USB connector, where the accessory controller can be operable to receive information from a personal computing system by way of the computer interface connector. The personal computing system can obtain the information by reading and retrieving the information from a CD ROM or other media or the personal computing can be utilized to access a local or wide area network to retrieve information to be uploaded to the data module. The accessory controller can be operable to upload the received information to the data module. The data module, now containing the uploaded information, can be plugged into the data module receptacle connector, through which the on-board controller can now communicate with and retrieve data from the data module now containing the information uploaded to the data module from the computer
[0022] The removable sound module purchased initially or subsequently can allow the purchaser to continue their purchase experience through the use of the sound module function.
[0023] After purchasing an initial sound module, the consumer can transport the selected body and selected sound module to a component collection station having a storage area for chassis styles for consumer pickup. The component collection station can be constructed to appear like an auto body parts shop. The consumer can at this point obtain the selected chassis style. The chassis styles can include motorized standard car chassis, non-motorized standard car chassis, motorized raised truck chassis and non-motorized raised truck chassis. The consumer can transport all of the selected items to an assembly station having custom tooling adapted to interface and drive an attachment member, which is adapted to attach the vehicle chassis to the vehicle body. The assembly station can also include a timer function that can start and stop a timer in order to time how long it takes the consumer to complete the assembly process.
[0024] An accessory station including a display having a display board for displaying accessory items and a work bench for in-store sampling and installing accessories can be positioned proximate the assembly station. The consumer can take the assembled vehicle to the accessory station and try out various accessories in order to make purchase selections. This station can be visited by consumers who have already purchased vehicles during a previous visit to the retail store or are visiting the store just to browse or desire to further customize a vehicle being purchased during a current visit.
[0025] The retail store space can also include a personalization station having computer work stations and integral toy garages sized for insertion of the toy vehicle and having a reader operable to scan and interpret an encoded identifier. Each body and/or chassis can include a bar code, radio frequency identifier (RFID), or other encoded identifier that has encoded therein identifying information relating to various features including the selected body style, the color, and the selected chassis type. An encoded identifier can be attached to the vehicle body and/or vehicle chassis. One reason for possibly having an encoded identifier on both the body and the chassis is to separately identify the body and chassis type and features. The encoded identifier can be read and interpreted by the reader and the reader can be further operable for transferring the vehicle body style information obtained from the encoded identifier to the computerized work stations where said work stations can be operable to create an electronic record or profile in memory containing body style information, other vehicle information including accessories and consumer information.
[0026] The computerized work station can be designed to receive other vehicle related information input by the consumer including information relating to accessories installed and add the information into the record. The record or profile can be assigned an identifier, such as for example, an alphanumeric designator or RIN (ride identification number), that is directly correlated to the profile and the associated resulting toy vehicle configuration. The RIN can be formatted to have embedded therein a member number, vehicle body and chassis identifier and etc. . . . Also, a graphical caricature or image of the resulting configuration (which can generally be referred to as an Avatar) can be generated and stored in the profile for recalling and viewing in the future.
[0027] Once the consumer has completed the original purchase experience, the consumer can electronically visit via an on-line experience a web site the provides the consumer the ability to continue the purchase experience by recalling the profile, viewing the image, modifying the configuration with different accessories and dynamically modifying the image being viewed, electronically communicating an image of the configuration to others, printing the image or ordering professionally printed posters containing the image with selected or original text, purchasing a wholly new configuration or modify the original configuration with other accessories, and previewing and purchasing new sound/data modules.
[0028] For example, a modular toy vehicle assembly can be capable of sound playback and various other electronic animations. The invention can include a sound module having a programmable electronic storage medium and controller function operable to control receipt and storage of sound data and other electronic data for initiation of electronic animation to the electronic storage medium and control transmission of sound data.
[0029] The toy assembly can be such that the electrical housing portion of the chassis can be adapted to receive the sound module and/or can be housed with an externally mounted or connected or otherwise associated accessory, such as for example, a trailer. The accessory can also have an auxiliary audio output in addition to a speaker output, such as for example, for a headphone jack. The accessory can also have other interfaces and/or connections for other types of audio electronic systems. The controller function that is operable to control receipt and storage of sound data can be operable to interface with the personal computing system to download audio sound clips stored on the personal computing system where said first connector can be a standard data interface connector for personal computing systems, such as for example, a USB type connector. The toy assembly as described above having first and second connectors can alternatively have the first and second connectors combined functionally and physically into one connector, such as for example, a USB type connector. The data stored on the module can include data other than audio sound data, such as for example other electronic animation control data such as data to control flashing of lights.
[0030] The process can include the steps using a personal computing device, such as for example, a personal computer (PC), personal data assistant (PDA) or other like computing device to connect to a local or wide area network (LAN or WAN), such as for example, the internet, to access remotely stored audio sound files and/or data files and to download the files to the personal computing device. For example, a provider of audio sound clips and/or data files particular designed to function with a given toy design can provide a web site that can be accessed by the toy owner.
[0031] The system can be designed such that when a previous purchaser navigates to a web site having a user interface log in page where the purchaser can enter the RIN number, which will recall the profile such that the appropriate sound modules can be identified for future purchases. The web site can provide a functional interface that allows the owner to navigate to, sample, and select files for download. The data file to be selected can merely be a music data file, for example an MP3 music file of a song by a popular musical artist. Once selected, the owner can download the file to their personal computing device. Once downloaded the process can include the step of communicably connecting the sound module to the personal computing device by way of a standard interface connector, such as for example, a USB connector. This on line option can also include a custom sound mixing and animation function. The interface can provide a means for a consumer to develop their own mixture of sounds and animation that can be downloaded as a data file once the mix is complete. The custom mix can be uploaded to a sound card, which can be plugged into the toy assembly.
[0032] The sound module can have a control function, implemented in circuitry and/or firmware, that can communicate with the personal computing device for the purpose of uploading the previously downloaded file to the sound module. The control function can also control the transmission of the data file from the sound module through the connector. The sound module containing an electronically stored audio sound and/or data file can be communicably connected to the toy receptacle. The toy can then access the file on demand. Optionally the owner of the toy can also purchased multiple preprogrammed sound modules that are read only or reprogrammable. The owner can also purchase blank sound modules with upload capability.
[0033] Once installed in the receptacle of the toy, the toy can access one or more data files stored on the sound module. The data files can be merely audio files that are stored on the sound module and the toy has a control function to access the data and play back the audio sound clip. Alternatively the data files can include audio files as well as other corresponding control data that the toy controller can access for controlling other toy functions, such as for example, toy lighting and/or movement.
[0034] Another on-line example of a continuation of the purchase experience can be the participation in an on-line game or activity utilizing an Avatar of the purchaser's toy assembly where the purchase can utilize their personal Avatar to compete or participate in games or activities individually or with/against other known purchasers and their respective Avatar. A purchaser can access via the internet a secured network by navigating to a web site having a log in user interface. The purchaser can log in by entering an appropriate user identification (for example the RIN) and password.
[0035] Once the purchaser has logged in, the purchaser and navigate to various user interface functions. For example the purchaser can view information relating to their type of toy assembly generally, or information relating to a purchaser's member account or status of a placed order. The purchaser can also view information specifically related to the purchaser's RIN number, for example the latest version of their toy assembly Avatar. The purchaser can also navigate to games and activities where the purchaser can enter the Avatar of their toy assembly in the various games and activities. The purchaser can also set up activities and games to compete against another known purchaser and their respective Avatar. This can be performed real time with both purchasers and their respective Avatars participating. The accessory module option of the toy assembly can act as a HUB and enhance this experience by communicably linking the toy assembly to the respective personal computing systems being utilized for the game or activity. The accessory module can communicably link the toy assembly to the respective personal computing system by way of a hard wired or wireless link. This connectivity can allow the on-line game or activity to initiate, by way of the personal computing system, a sound play back or animation of the toy assembly in real time responsive to an event in a game or activity.
[0036] As a further option of this expansion of the on line experience, the RIN of a purchaser can be placed on a sound module along with other firmware that allows the purchaser to connect the sound module to an accessory module, which is in turn connected to a personal computing system, and automatically access the purchaser RIN account without having to key in information manually by way of a log in user interface.
[0037] These and other advantageous features of the present invention will be in part apparent and in part pointed out herein below.
BRIEF DESCRIPTION OF THE DRAWINGS
[0038] For a better understanding of the present invention, reference may be made to the accompanying drawings in which:
[0039] FIG. 1 is a process flow of the original purchase business;
[0040] FIGS. 2 , 2 A, 2 B are illustration of retail flows;
[0041] FIG. 3 is a functional flow diagram showing the process of downloading to a sound module and installing a sound module is shown;
[0042] FIG. 4 is a functional block diagram of the sound module is shown;
[0043] FIG. 5 is an illustration of a toy assembly with sound module installed; and
[0044] FIG. 6 is an illustration of a accessory module with a sound module installed.
[0045] While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail. It should be understood, however, that the drawings and detailed description presented herein are not intended to limit the invention to the particular embodiment disclosed, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present invention as defined by the appended claims.
DETAILED DESCRIPTION OF INVENTION
[0046] According to the embodiment(s) of the present invention, various views are illustrated in FIGS. 1-6 and like reference numerals are being used consistently throughout to refer to like and corresponding parts of the invention for all of the various views and figures of the drawing. Also, please note that the first digit(s) of the reference number for a given item or part of the invention should correspond to the Fig. number in which the item or part is first identified.
[0047] One embodiment of the present invention comprising a method for continuing a retail purchasing experience teaches a novel method for continuing the purchase experience for a consumer's purchase of a semi-custom toy assembled and customized by the consumer. The method includes creating an individualized profile or record memorializing the purchase, customization and personalization experience when assembling, customizing and purchasing a semi-custom toy. A unique identification number can be assigned to the profile for future recall of the record. The purchasing or customizing experience can continue on-line or in a physical retail store by recalling the profile.
[0048] The details of the invention and various embodiments can be better understood by referring to the figures of the drawing. Referring to FIG. 1 , a process flow of the original purchase business model 100 is shown. The process flow shows various stages of the purchase experience as a consumer smoothly transitions between the stages of customizing, assembling, accessorizing and personalizing a modular toy vehicle designed based on their selections. The original purchase experience can be accomplished in a physical retail store or by navigating among on-line user interface pages or virtually via an on-line experience by visiting a web site. For the on-line experience, graphical user interface technology well known to those skilled in the art can be utilized to simulate a physical in-store retail purchase experience. As an alternative the on-line virtual in-store experience can be a 3D experience. The consumer's transition between the stages or stations can be directed by the retail space floor plan and/or a customer service representative or by the graphical user interface in an on-line environment. The physical retail space is described herein, but as indicated above the same can be accomplished on-line using a graphical user interface that allows the consumer to select each stage by navigating among user interface pages and view and select the options made available at each stage. Also, as mention, a virtual tour can be utilized. The assembled custom vehicle can be graphically presented automatically based on selections and viewed or there can be some manual interactions utilizing various computer interface control devices such as for example the mouse for selection and moving graphically presented items.
[0049] The Introduction/Greeting step is reflected by functional block 102 . Upon entering the retail space, or by navigating to the greeting page on-line, customers can be familiarized with the purchase experience and can be started in the process. Customers can be directed to pass through a simulated “Shop” door (garage like, auto-body/mechanic shop door) and into the toy vehicle body selection station.
[0050] The toy vehicle body selection stage is indicated by functional step 104 , where a wide selection of vehicle body styles can displayed, in various colors and degrees of paint finish. For example, each vehicle can be offered in a certain number of color options including solid colors and “custom” paint finishes. Bodies with extensive painting and detailing can carry a higher retail price than the more basic solid colored vehicle bodies. The stock configuration of a toy vehicle can comprise of the vehicle body on a car or “street” chassis, four stock tires, four stock rims and a fifteen to thirty second sound chip or sound module which plays a mix of car sound effects and music. The various body styles can have uniform chassis interface mating designs such that all body designs can mate with the same chassis design.
[0051] Once customers select their vehicle body, they can proceed to a chassis template sampling station 209 . Here customers can see how their selected vehicle body will appear on various chassis styles, for example, both a “street” chassis and a “monster”/off-road or raised truck chassis. The “street” chassis can be considered a stock item and therefore included in the base price of the vehicle. The “monster” chassis can carry an additional charge.
[0052] The customer can proceed to a sound module selection station 106 , where customers can have the option of listening to and selecting additional sound modules for their vehicle in addition to a standard stock sound module, which can be provided as part of the standard purchase. For example, in addition to the sound module that is included with a standard purchase, there can be a plurality of additional sound choices, and each can be for example 30 seconds in length, which can be purchased separately. The sound module selection station can be designed, for example, like a kiosk that resembles a speaker display similar to those typically seen in car audio departments or stores. By selecting buttons on a display, customers can hear the full 30 second playback from each chip. However, the file can be more than a 30 second playback, for example the file can contain a full MP3 format version of a popular song.
[0053] The customer can select the actual chassis to be purchased at the component collection station step 108 . The customer can then proceed to the assembly step 110 , performed at the assembly station. In the physical retail experience they can also be introduced to the timed assembly Pit Challenge—a timed competition where a consumer can take part in an assembly process time competition.
[0054] The consumer can start and stop a timer made available at the station, that can allow the assembly time of each consumer to be timed. A display can be provided which shows the elapsed time. A display can also be provided listing the names of the consumers with the fastest assembly times. The timed assembly competition can be referred to as the RZ Pit Challenge where a timed competition is conducted in which customers compete against the clock to see how quickly they can assemble their vehicle. In order to assemble the vehicle, consumers can use a powered screwdriver or powered wrench with a special bit to drive the attachment member, such as for example as a threaded bolt, to quickly and easily assemble their vehicle. The wheel assembly is a simple snap-on process that requires no tools. Immediately prior to assembly, customers will press a button to activate a stopwatch that is built into the assembly table . . . and will again hit the button to stop the timer when they have finished assembling their car. Their time/score is recorded onto a card by the Pit Challenge Crew Member, service representative, and handed to the customer. Alternatively the Pit Challenge can be automated to provide print out of timed scores. The Pit Challenge would not be available for an on-line purchase experience.
[0055] At another station in the process, the personalize station, the customer can be prompted to enter their time in the computer in order to receive their RZ Pit Challenge score and pit ranking to be saved as part of the profile. With their time card and assembled toy vehicle back in their basket, the customer can be directed to the customize accessory station to view the various customizing accessories and decorating options.
[0056] A step in the process can be the accessorizing step 112 where customers can move through an accessory station, including a display having a display board for displaying accessory items. Several displays of aftermarket accessories to customize and decorate their modular toy vehicle, such as for example—Rims, Tires, Exterior Accessories and Decals. Instructional displays can be provided to inform customers of the locations of the universal accessory mounts and to provide visual and written instructions on how to install the accessories at those locations on the vehicle.
[0057] Customers can decorate and detail their cars with a wide selection of decals. The accessories can be designed to fit all vehicles purchased in the store and can be interchangeable between vehicles. Accessories can be attach to the front, sides and rear of the vehicles via a tab-slot system and to the roof and hood of the via hidden magnets. For example, the accessories can include hood ornamentations (for example hood scoops), roof ornamentations (for example emergency vehicle lights), rear trunk ornamentations (spoilers), tail pipes, side pipes and various other items.
[0058] A step in the process can be the personalize step 114 where a customer is directed to move through a personalization station having computerized work stations and integral toy garages sized for insertion of the toy vehicle and said garages having a reader operable to read and/or scan and interpret an encoded identifier where said readers are communicably linked to the computerized work station. The readers can be for example optical readers for scanning and interpreting bar codes or RFID readers. Each vehicle chassis and body type can have an encoded identifier attached that provides specification of that type body and chassis. The customer can also be prompted to input additional information for saving in a profile that can later be retrieved. Packaging for accessories purchased can also have encoded identifiers on one of the exterior surfaces. Packaging for purchased accessories can also be scanned and/or read by the reader and the accessory information can be added to the profile. It is at this stage that an Avatar of the toy assembly can be generated, displayed and stored for future access. These profiles created can periodically be uploaded from the local personalize station to a centralized.
[0059] The toy garages can have an integral reader for reading the encoded information. The personalize station can consist of several computer workstations where customers register their vehicle. Customers can enter information about themselves (including names, nicknames, Email Address, Street Address, date of birth, and etc. . . . ) and about their vehicle to create a vehicle Title with its own unique R.I.N. (Ride Identification Number) and personalized License Plates for their vehicle. For example, if the customer has added accessories at the accessorizing station, the customer can enter the accessory information at this point. Entry of accessory information can be performed by scanning identifiers on the packaging of the accessory. The computing system can also be equipped to display a visual depiction of the customized vehicle. A color printout or wall size poster can also be provided. The customer can view now and later on-line an Avatar and forward the image via Email to others. This R.I.N. number can later to used to access information about that specific vehicle online at web site and to gain special access to online activities and games. The consumer can also have the option to give the vehicle a name. For example, the consumer can select a name for a personalized license plate. Embedded within the RIN number format can be the body style number, chassis style number, point of sale identifier (retail store ID), date of purchase, transaction number and date of birth, in order to create a unique RIN number.
[0060] The personalize station can comprise several computer workstations where customers register their toy vehicle. For the physical retail experience, customers can be prompted to “park” their vehicle in their toy garage, or “carport” that is attached to the left or right side of the workstation. The garage can house an internal laser scanner that scans the barcode sticker that is affixed to the body of each vehicle. Other encoded tags and readers can be utilized. The barcode identifies the model and color of the vehicle. Additionally customers are asked to identify the type of chassis they selected and which rim design they chose to put on their vehicle. As this data is captured, the computer can be operable to build an image of the customer's vehicle on the screen; body, color, chassis, rims. This same process is used to create the vehicle's unique RIN (Ride Identification Number). Customers can then be prompted to enter information about themselves in order to complete the creation of a vehicle Title and personalized License Plates. This registration process and RIN number can later to used to access information about that specific toy vehicle online at a designated web site and to gain special access to online activities and games. During an online experience, the various selections made by the consumer can be captured and stored as part of the profile.
[0061] Referring to FIGS. 2 , 2 A and 2 B, optional retail space flows are provided. Referring to FIG. 2 , an overhead plan view of the retail floor layout 200 is shown. Various stations can be strategically placed within the floor plan in order to provide a smooth process flow as well as providing an enhanced customer experience. Various fixtures and displays can be placed throughout the retail space to give the retail space the look and feel of an auto mechanic's shop or garage. The primary stations can be placed along the perimeter of the retail space in order to control customer traffic moving throughout the retail space. The retail space floor plan, display construction and arrangement can be designed to create a customer flow path that directs the customer along a path adjacent the various stations in a manner conducive to the selection, assembly, customization and personalization/registration of the vehicle for purchase. A customer can enter through an entrance 202 and proceed to a greeting station that can be proximately located with respect to the entrance. At the greeting station 204 , a customer service representative can provide instructions to the customer as well as directing them to the appropriate station. The positioning of the greeting station and the entrance 206 within the retail space floor plan tends to channel the customer to the vehicle body selection station.
[0062] The customer service representative can direct a customer through an entrance 206 to the entrance of the customization experience. The toy vehicle body station 208 is shown against a side wall of the retail space proximate the entrance to the retail space and the greeting station. Included in the selection station 208 is a template sampling station 209 provided to allow the customer to decide on a chassis style. Adjacent the selection station is a sound module station 210 where the customer can decide on a sound module selection. The sound module station is also positioned against one of the side walls of the retail space. Adjacent the sound module station against a side wall is the component collection station 212 where a customer can receive the selected chassis. This portion of the retail space floor plan labeled in FIG. 2 as the CHOOZE, SONICIZE and MOTORIZE areas for illustrative purposes is arranged and designed to create a customer flow path that directs the customer along a path adjacent the various stations in a manner conducive to the selection and assembly process.
[0063] The assembly station 214 is shown at a location proximate the component collection station 212 toward a central area of the retail space. The customer can assemble the modular vehicle at the assembly station. The accessory station 216 is shown positioned against a rear wall of the retail space. The accessory station can provide various accessories to further customize the modular toy vehicle. In addition, the accessory station can provide full size rims on display 215 for the customers' viewing. The customers can select from these rim designs on display. The play sized version of these full sized rims can be available for purchase. The accessory station 216 can provide a workbench 217 for installation and sampling of the various accessories. The Accessory stations 215 and 216 can be arrange in a more parallel arrangement to create a channel directed toward or about the Assembly station 214 . The areas labeled MOBILIZE and CUSTOMIZE can be designed to be more integral or sequential.
[0064] The personalized station 218 can be arranged against a side wall of the retail space. The personalized station can include multiple computer work stations having integral toy garages sized for insertion of the toy vehicle where the toy garage has a reader operable to scan and interpret an encoded identifier attached to the vehicle. The checkout station 220 can be positioned against a side wall proximate the entrance of the retail space.
[0065] FIGS. 2A and 2B , provide illustrations of alternative floor plan flows. Primarily the only change in flow plan flow is the combining of the Motorize Station and the Mobilize station.
[0066] Once the consumer has completed the personalized station process, a profile can be completed and stored for subsequent recall to continue the original purchase experience on-line or in a physical retail store. Once a profile has been created, it can be recalled for subsequent purchases, including sound modules. The sound module function can be a useful tool for continuously updated the toy assembly sounds and animations. Referring to FIG. 3 , a functional flow diagram showing the process of downloading to a sound module and installing a sound module is shown. The functional flow diagram 300 includes a first functional block 301 representing the personal computing system download function. This functional step is representative of a user utilizing their personal computing system, such as for example a personal computer to access via a wide area network or local area network a remote database containing data files for download. The user can access for example a website via the internet. Once the user accesses the website, a user interface can be provided that allows the user to navigate to a data file and download the data file to their personal computing system. Various type data files can be made available by category based on compatibility with certain toy functional capabilities. For example, certain data files may contain control data for flashing lights of the toy in a certain sequence, however, this function may only be compatible with certain toys.
[0067] Once the data file has been properly downloaded and stored on the personal computing system, then the user can begin the upload process. The functional block 302 is representative of the upload to sound module function where the user accesses the data file now residing on the personal computing device and then uploading the data file to the sound module. The user interface on the personal computing system can provide the appropriate prompts for selecting and uploading the desired data files. In order to perform the upload function, the user can communicably connect the sound module to the personal computing system by way of interface connection. The sound module can be equipped with a standard interface connector for communicating with a personal computing device such as a personal computer. The standardized connector can be a standard USB connector that can be connected to a personal computer through which a data file can be uploaded to the sound module.
[0068] The data file can include sound clips as well as other data formatted in a fashion to be utilized as control data by a target toy device. Once the data file has been uploaded to the sound module, the sound module can be disconnected from the personal computer and utilized in the target toy device. A functional block 304 is representative of communicably connecting the sound module to an external receptacle of the toy device. The owner can take the sound module and plug it into an external receptacle located on the toy device. The external location of the receptacle should be readily accessible by the user and provides for easy insertion of sound module to provide a communicable connection. Once the sound module has been inserted into the receptacle, the toy can now access the data file contained on the sound module. As an alternative to uploading a data file by way of a personal computing device, the owner can purchase pre-programmed sound modules for insertion into the sound module external receptacle of the toy. In order to access or activate the data files contained on the sound module, the owner must provide the appropriate input which could include depressing a button or switching a switch that is located on the toy device or remotely selecting a function. The activation of the data file contained on the sound module is represented by a functional block 306 .
[0069] Referring to FIG. 4 , a functional block diagram of the sound module is shown. The sound module 400 can include various functional components. Primarily, the sound module should include a storage media or electronic storage media for storing a data file containing for example audio sound clips or other control data files. The electronic storage media 402 can be configured to be readily accessible by the control function 404 of the sound module. The controller function can be implemented by way of firmware and/or electronic circuitry. The controller function can be operable to control the receipt of control signals and data by way of I/O connector 406 as well as transmit data and control signals by way of the same connector. Optionally, the control module can have a second optional I/O connector 408 such that there is a dedicated I/O connector for receipt of data files and for control signals relating to the storage of information and a separate connector related to the transmission of data files from the sound module and the related control signals.
[0070] When the sound module is connected to a personal computing device, the sound module and the personal computing device can communicate through an I/O connector to upload data files to the sound module. When the sound module is communicably inserted into the receptacle of the toy, the control function of the toy can access the data files on the sound module. The consumer's vehicle profile once created can be retrieved at a later time to continue the experience.
[0071] Referring to FIG. 5 , a toy assembly 500 is shown. FIG. 5 illustrates the toy assembly as a toy vehicle chassis 502 having a recessed area 506 wherein a sound module 507 is installed such that it is recessed below the surface 504 . FIG. 5 also illustrates an accessory module 508 , which can provide connectivity to a personal computing system 510 having access to a wide area network 512 such as for example the internet. The accessory module can act as a HUB for the toy assembly providing connectivity to a computing device. The sound module is shown plugged into the toy assembly, however, optionally the sound module could be plugged into the accessory module having a sound module port. This HUB configuration and allow the computing system to access information contained on the sound module, such as for example the RIN number. A purchaser can access the internet via a computing system and navigate to a web site, which provides a login user interface. Once the RIN has been accessed either automatically by way of the HUB interface or by manual entry, the purchaser can access the profile correlating to the RIN. The purchaser can view and modify the toy assembly design thereby creating a revised Avatar that can be stored for future access. The purchaser can also access various games and activities that relate to the toy assembly. For example, in the case of a toy vehicle, an interactive car racing game can be accessed by the purchaser. The purchaser can enter their personal Avatar based on their RIN profile into the racing game to compete against other generic Avatar's randomly selected by the gaming engine. Alternatively the purchaser can arrange for a racing game scenario where the purchaser and purchaser's Avatar can compete against the Avatar's of other known purchaser's, for example friends. Multiple purchasers and their respective Avatars can compete real time in an on-line environment where each of the purchasers are remotely located with respect to each other.
[0072] Referring to FIG. 6 , an illustration of an accessory module or HUB 508 is shown. The accessory module can have a port adapted to receive a connector 602 of a sound module 600 operable to communicably connect the sound module to the accessory module. The accessory module can optional have multiple ports for receiving and communicating to multiple sound modules. This configuration can allow the computing system to access multiple RIN numbers simultaneously, which can be utilized when multiple purchasers are accessing on-line games or activities through one computing system. Therefore, multiple purchasers can congregate at one location where there is a HUB having multiple ports and a computing system 614 having access to the internet. The accessory module 508 can have a main chassis 604 having a recessed area 605 where the portal can be located, such that the sound module is recessed below an exterior surface 607 of the main chassis.
[0073] The accessory module 508 can have an on-board Processor and RAM 606 for controlling operation. The accessory module can also have one or more wireless ports to a toy assembly and one or more wireless ports to the personal computer. Information can be retrieved from the sound module and uploaded to a sound module as described above. The on-line system of the present invention for continuing the initial purchasing experience by retrieving profile information can be implemented utilizing known software and hardware techniques. The accessory module can have wireless connectivity to a personal computing device 614 and to a toy assembly 612 by way of wireless ports 608 and 610 respectively. The accessory module can also have multiple wireless ports for multiple computing system connectivity and multiple wireless ports for multiple toy assembly connectivity.
[0074] The HUB configuration and the connectivity between a toy assembly and the computing system can allow the on-line gaming activity to initiate animation functions of the toy assembly, such as for example playback of music or flashing lights, by sending real time signals from the gaming engine corresponding with a real time gaming event to the toy assembly by way of the computing system and the HUB. The toy assembly can perform various animations and movements responsive to a gaming event. The wireless connectivity of the HUB can be Bluetooth, IR or some other wireless format. The connectivity can also be hard wired.
[0075] The various examples shown above illustrate a novel method for providing a consumer profile for a custom vehicle. A user of the present invention may choose any of the above methods, or an equivalent thereof, depending upon the desired application. In this regard, it is recognized that various forms of the subject method could be utilized without departing from the spirit and scope of the present invention.
[0076] As is evident from the foregoing description, certain aspects of the present invention are not limited by the particular details of the examples illustrated herein, and it is therefore contemplated that other modifications and applications, or equivalents thereof, will occur to those skilled in the art. It is accordingly intended that the claims shall cover all such modifications and applications that do not depart from the spirit and scope of the present invention.
[0077] Other aspects, objects and advantages of the present invention can be obtained from a study of the drawings, the disclosure and the appended claims. | A method for continuing the purchase experience of a personalized semi-custom toy in a follow-up on-line interface experience or in a physical retail experience. The method includes the steps of a consumer assembling a semi-custom toy configuration by selecting from among multiple major component styles and assembling the major component styles selected and selecting additional optional accessories to add to the major components resulting in a semi-custom toy configuration; the consumer inputting identifiers for the selected major component styles and accessories so that an over all toy identifier can be assigned, which is associated with and correlates to the resulting configuration; memorializing the information electronically into a consumer/toy-configuration profile stored in a database having electronic memory for future retrieval and manipulation. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates in general to a security guard for a valve on a storage tank and more specifically concerns high strength valve guards that serve as a deterrent to the theft of toxic or hazardous materials.
2. Description of the Prior Art
Various types of valve security guards are known in the art for placement over valves and other regulating type devices used on storage containers to prevent any unlawful operation thereof. Examples of these prior art devices are disclosed in U.S. Pat. Nos. 4,380,247; 4,513,773; 4,254,888 and 4,899,781. Although the guards disclosed in such patents are useful for their designed purpose, none of them are structured to prevent unauthorized use of a dispensing valve for an anhydrous ammonia storage tank.
SUMMARY OF THE INVENTION
The present invention provides a valve security guard for a storage tank having a valve for dispensing material from the tank, which valve includes a valve casing, a valve stem that extends outwardly from the casing and an operating handle at the outer end of the stem. The security guard is primarily formed from a cover with a closed end and an interior with an open end for enclosing the valve handle and means for securing the cover on said handle. The securing means is formed of apertures in said cover and an elongated shaft member that extends through said apertures and is lockable in a fixed position located behind the handle to secure the cover thereon.
The cover interior has inner and outer chambers formed in a tiered configuration so that the outer chamber has a diameter greater than the inner chamber to define a circular interior ledge and the handle is received in the inner chamber. Preferably, a slip ring that is sized to be received within the inner chamber of said cover is located intermediate the valve handle and the periphery of the inner chamber. Further, the guard includes a shield means with a central opening through which the valve stem can be positioned. The shield means is of a size for being positioned within said outer chamber of the cover interior to seat against the interior ledge for substantially closing off the inner chamber to increase the security of the guard.
The foregoing and other advantages of the present invention will appear from the following description. In the description, reference is made to the accompanying drawings, which form a part hereof, and in which there is shown by illustration, and not of limitation, a specific form in which the invention may be embodied. Such embodiment does not represent the full scope of the invention, but rather the invention may be employed in a variety of embodiments, and reference is made to the claims herein for interpreting the breadth of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an exploded perspective view of a preferred embodiment of the valve security guard of the present invention;
FIG. 2 is an exploded side view of the security guard of FIG. 1 shown together with a valve assembly;
FIG. 3 is a cross-sectional view of the security guard of FIG. 1 assembled in position on the valve assembly of FIG. 2;
FIG. 4 is a side view of the security guard of FIG. 1 positioned on the valve assembly of FIG. 2;
FIG. 5 is a cross-sectional view of a cover and a shaft member forming part of the security guard FIG. 1;
FIG. 6 is a cross-section similar to that shown in FIG. 5 but with the shaft member viewed from opposite side; and
FIG. 7 is a partially exploded plan view of the cover, shaft member and locking bar for the shaft member.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention is designed to provide a valve security guard shown generally at 10 in FIG. 1 for a storage tank. The security guard 10 is particularly appropriate for use with storage tanks holding toxic or other dangerous materials as the structure of the guard is made of high strength and tamper resistant materials in order to provide a highly effective securement device.
The security guard 10 principally includes a cover 11 and an elongated U-shaped shaft member 12 designed to coact together to retain the cover in a fixed position on the handle. In addition to the cover 11 and shaft member 12 , the security guard 10 preferably includes a slip ring 13 , a disk shaped shield means 14 and a shield ring 15 in addition to spacing washer 16 as needed, all for the purposes as described below.
With reference now to FIGS. 1, 2 and 3 , the cover 11 is generally of a sleeve shape and has a closed outer end 18 and an interior cavity 19 having an open end 20 . The interior cavity 19 is in a tiered configuration with a circular shaped inner chamber 21 and an outer circularly shaped chamber 22 having a diameter larger than that of the inner chamber 21 to form an interior ledge 23 . As is best shown in FIG. 1, the sidewall 17 of the cover 11 is formed with two pairs of opposed aperture 25 through which the shaft member 12 is disposed, as can clearly be seen from FIGS. 1 and 5 - 7 .
The shaft member 12 is of an elongated U-shaped configuration having a rounded end 27 and opposite free ends 28 and 29 that are designed to coact with a locking bar 30 to secure the shaft member 12 in place. The shaft member 12 and locking bar 30 are manufactured by Kryptonite Corp. and are of a construction well-known in the art.
Referring again to FIGS. 1, 2 and 3 , the interior cavity 19 of the cover 11 is designed to serve as a housing for an operating handle 34 of a valve assembly 35 that further includes a valve body 36 , a valve stem 37 and locking mounting nuts 38 and 39 for securing the stem 37 with the body 36 . As can be seen from FIG. 3, the valve assembly operating handle 34 is received within the inner chamber 21 of the cavity 19 . Also enclosed within the inner chamber 21 is the slip ring 13 that is sized for seating in the chamber 21 in such fashion that it is free to rotate relative to the cover 11 . The use of the slip ring 13 , although not essential to the present invention, is highly desirable as without the slip ring 13 , it may be possible to tilt the cover 11 against the handle 34 to obtain unauthorized actuation of such handle. Obviously, the slip ring 13 prevents such unauthorized action by permitting the cover 11 to rotate without actuation of the valve assembly 35 .
In like fashion, the shield 14 is also not essential to the present invention but is highly helpful in preventing tampering with the valve assembly 35 by means of the open end 20 of the interior cavity 19 . The shield 14 includes a center hole 40 so that the shield can be positioned on the valve stem 37 intermediate the handle 34 and the locking nuts 38 and 39 . As can best be seen in FIG. 3, the shield 14 has a diameter approximately equal to the inner diameter of the outer chamber 22 of the cavity 19 and seats against the cover interior ledge 23 to seal off the cavity inner chamber 21 .
The integrity of the security guard 10 is further enhanced through the use of the shield ring 15 that is designed to fit over the locking nuts 38 and 39 and prevent access thereto by unauthorized personnel. The washers 16 serve simply as spacers between the shield 14 and operating handle 34 to maintain the shield 14 in proper position for completely sealing off the inner chamber 21 . Accordingly, the security guard of the present invention provides a highly secure means for preventing unauthorized operation of the valve assembly 35 , as indicated by FIG. 4 .
Although the invention has been described with respect to a preferred embodiment thereof, it is to be understood that it is not to be so limited, since changes and modifications can be made therein which are within the full intended scope of this invention as defined by the appended claims. | A valve security guard is provided for a storage tank having a valve for dispensing material from the tank and includes a cover with a closed end and an interior with an open end for enclosing a valve handle, and a shaft member that extends through apertures in the cover that is lockable in a fixed position located behind the valve handle to secure the cover thereon. | 5 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims priority from co-pending provisional application Ser. No. 60/760,072, filed Jan. 19, 2006.
TECHNICAL FIELD
[0002] The invention relates generally to optical members having resistively heatable coatings and more particularly to patterning such coatings.
BACKGROUND ART
[0003] Single layer or multi layer coatings are often used to achieve desirable optical characteristics for windows used in vehicles, homes and buildings. For example, Southwall Technologies, Inc. sells a film under the federally registered trademark XIR. The XIR film is incorporated into a glass lamination to significantly reduce solar heat gain through the glass lamination. The control of solar heating is significant to some applications, such as automobile windshields.
[0004] U.S. Pat. No. 6,204,480 to Woodard et al., which is assigned to the assignee of the present invention, describes the use of an optical coating on a vehicle window to heat the window for purposes of providing de-icing or defogging. The coating is a thin film stack that is electrically conductive, but is sufficiently thin to be substantially transparent. The term “transparent” is defined herein as the ability to transmit at least 30% of radiation within the visible range of the light spectrum. Electrical connections to the thin film conductive coating are provided by bus bars. The bus bars may be patterned to achieve desired current distribution or to focus heating into certain regions of the window. The patent is herein incorporated by reference.
[0005] U.S. Pat. No. 6,703,586 to Kast is also assigned to the assignee of the present invention and is incorporated by reference. Kast teaches that localized heating of a window, such as a vehicle windshield or sidelight, can be provided by dividing an electrically conductive optical coating into high and low heating zones.
[0006] It is well known that heat energy may be delivered to “glazing assemblies” by incorporating resistive heating elements either on or within the glazing assembly. Then, a voltage may be applied across the resistive heating elements to cause localized heating of the elements, resulting in heat transfer to the surface of the assembly. The purpose of the localized heating may be one or more of demisting, defrosting, de-icing, or improving human comfort. The resistive heating elements may be designed with a roughly sinusoidal two-dimensional pattern in the plane of the glazing and may comprise an array of electrically parallel opaque conductors with individual widths typically narrower than 75 microns. The waveform of the conductive elements may consist in part of repeating patterns which are substantially linear and substantially parallel to one another.
[0007] A concern with prior art approaches is that the incorporation of resistive heating elements on or within the glazing assembly may adversely affect the optical performance of the assembly. For example, when applied to a window of an automobile, visibility may be affected, particularly during nighttime driving.
SUMMARY OF THE INVENTION
[0008] In accordance with the present invention, a pattern of conductive traces is designed to avoid occurrences of adjacent trace segments that are linear and parallel. It has been determined that multiple linear elements or sub-elements with predominantly parallel angular orientations are a basic cause of some optical distortions. Although spaced apart from one another, linear, parallel sub-elements of a conductive pattern may cause additive diffraction-like visual effects which can be annoying and distracting. The visual effects are easily noticed in transmissive viewing conditions in which a distant point source of light is viewed through a glazing that is close to the viewer, as would be the case with nighttime driving or riding in a vehicle with oncoming traffic or adjacent street and safety lighting. For example, occupants of a vehicle may notice two opposed rays emanating from an image of an external point source of light, with brighter sources creating more intense sets of rays. The ray-like disturbances are oriented at right angles to the predominant axes of the linear, parallel sub-elements of the heating elements.
[0009] In one embodiment, the pattern of electrically conductive traces is defined by a large angular distribution with respect to intersections among the traces. That is, the traces intersect at irregular angles, but combine to form electrical paths for the flow of current. Power connections, such as busbars, are provided to induce the current flow when a power source is connected. The pattern may be quasi random, as would be the case when the pattern includes randomization within a sub-pattern, but the sub-pattern repeats across the surface of a transparent member, such as a windshield. Individual traces may be linear, but the randomization avoids the occurrences of adjacent trace segments that are parallel.
[0010] Alternatively, the traces may be curved.
[0011] In another embodiment of the invention, the pattern is a continuous series of sub-elements that are preferably exclusively curved in the plane of the surface on which the sub-elements are formed. As one possibility, each conductive trace may be a resistive element in the form of a continuous series of semicircular trace segments. Alternatively, a resistive element may be a continuous series of quarter-arc trace segments or partial elliptical trace segments.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a schematic view of an indoor testing method used in determining the cause of the “star filter” effect and means for reducing or eliminating the effect.
[0013] FIG. 2 is a photograph of the “star filter” effect.
[0014] FIG. 3 is a schematic view of prior art straight traces connected to a bus bar for use with an automobile window or other optical member.
[0015] FIG. 4 is schematic view of prior art “wavy” traces as an alternative to the straight traces of FIG. 3 .
[0016] FIGS. 5-9 are photographs taken through windows in order to show optical distortions as a result of heating elements.
[0017] FIG. 10 is a schematic view of an array of heating traces in accordance with one embodiment of the invention.
[0018] FIG. 11 is a schematic view of an array of heating traces in accordance with a second embodiment of the invention.
[0019] FIG. 12 is one period of a trace as shown in FIG. 10 .
[0020] FIG. 13 is a comparison of optical effects of conventional microwires, the pattern of FIG. 10 , and the pattern of FIG. 11 .
[0021] FIGS. 14-17 show various alternative embodiments to the present invention.
[0022] FIG. 18 is another embodiment of the invention, wherein the pattern is formed of linear elements having irregular orientations.
[0023] FIG. 19 is a side view of metal traces on a glass plate.
[0024] FIG. 20 is an illustration of an example of a grating structure.
[0025] FIG. 21 is a schematic illustration of the principle of optical structure of a front headlight of a vehicle.
[0026] FIG. 22 is a schematic illustration of the area of directional lighting.
[0027] FIG. 23 is a schematic illustration of an experimental setup which may be used in evaluating samples.
[0028] FIG. 24 is a simulated image of illumination through a circular aperture.
DETAILED DESCRIPTION
[0029] While the invention will be described primarily with respect to automobile windshields, other applications are contemplated. For example, the invention may be utilized with windows of homes or buildings or with reflective surfaces, such as rearview mirrors. In attempting to augment or supersede known films, such as XIR-type films sold by Southwall Technologies, prior art conductive patterns of elements and sub-elements were evaluated. Under certain likely viewing conditions, a negative viewing effect of the known heating elements was observed. The presence of conventional elements caused a pair of angularly crossed ray-like bright lines to be seen emanating from distinct point sources viewed at nighttime through the glass. A similar problem is reported with a microwire-heated backlight (rear window) in a vehicle when a driver views headlights of a following car reflected by the internal rearview mirror.
A. Experimental Process
[0030] The problem of a “star filter” effect was identified with simulated microwire patterns (quarter-arcs+straight segments in modified sinusoidal pattern). A sample was taped to a car windshield. Observations and photographs showed the “star filter” effect during nighttime transmissive viewing conditions. The problem was confirmed using a second set of tests with a stationary car (headlines on and facing the viewing station) located approximately 80 feet from a conventional heatable windshield sample and two models with straight traces and simulated conventional traces. A modified set of continuous curvilinear lines containing no intentionally linear segments (i.e., made only of curved sub-elements) exhibited far superior performance in the nighttime point-source transmission situation. The ray-like bright lines were much reduced in intensity. Subsequently, further sets of various patterns, again made only with curved elements, exhibited virtually no ray-like bright lights.
[0031] For purposes of the experimentation, samples were all made with opaque ink or metal deposited on glass or film in various patterns and linewidths. The film samples were laminated in glass to reduce the effect of surface haze. The baseline heatable microwave windshield sample was not modified.
[0032] There were two test methods, namely the outdoor test method and the indoor test method. For outdoor testing, the sample was placed at a desired orientation (vertical or tilted) and the observer was situated such that the viewing zone of the glass (line of sight to the target) was approximately 45-50 cm from the eyes. The observer looked directly at one or a pair of vehicle headlights at a distance of 25 meters. The test was performed at nighttime in a low-light situation. General street lighting did not affect the test. The observations could also be made when viewing passing traffic while the vehicle was parked parallel to one side of a straight road. The observer viewed the subject patterned glazing sample and an unpatterned glazing sample of otherwise similar construction and noted the intensity and orientation of any ray-like patterns. A camera could be set to focus on the distant light sources in order to record the image.
[0033] The indoor test is represented in FIG. 1 . For the indoor test method, the sample 10 was placed at the desired orientation (vertical or tilted) and the observer (human or optical, such as a digital camera 12 ) was situated such that the viewing zone of the glass (line of sight to the target) was approximately 45-50 cm from the eyes, with the observer looking directly at a point source of light 14 at a distance of 5 meters. The test was performed in a darkened room, preferably with a dark background 16 behind the light source. The light source was adjusted by the choice of optics or an aperture plate to have a diameter within the range of 3 mm to 7 mm. A fiberoptic illuminator or indoor fifteen watt halogen lamp with a reflector could also be used. The observer viewed the subject patterned glazing sample and the unpatterned glazing sample of otherwise similar construction and noted the intensity and orientation of any ray-like patterns. Again, a camera could be set to focus on the distant light source in order to record the image.
[0034] In determining the results of the experimentation, it was noted that both the outdoor and the indoor tests showed that the conventional microwire heating glazing and the simulation of a similar pattern resulted in a double pair of objectionable diffraction-like rays seen to emanate from the light source. If the sample was rotated about the viewing axis slightly during the observation, the rays rotated exactly with the sample orientation. When the sample was tilted about the horizontal axis, the angles diminished, becoming closer to the horizontal plane. Other results were as follows:
(1) If a sample with a vertical straight-line pattern was observed, there was a single pair of rays emanating from the source, oriented at an angle normal to the lines in the pattern, in the same manner as a conventional diffraction grating; (2) Measurements of the angles of the linear sub-segments in the simulated and the conventional microwire windshield showed that they were normal to the angles of the emanating ray pairs and that they were not the same angle in both samples. The effect seen with the straight-line samples showed that the straightness of the elements contributed to the problem. The orientation dependency of the paired rays on the angle of the straight sub-segments showed that the predominant orientation of even small sub-segments in a regular pattern is an important factor; (3) The tilting of the sample affects the subtended angle of the linear elements and this explains the “flattening” effect viewed with the rays when the samples were tilted about the horizontal axis, further bolstering the theory of the elements as the root cause of the “star filter” effect; (4) New patterns were developed. One pattern of stacked quarter-arcs used the same linewidth, curve radius and element spacing as the simulated microwave pattern. This pattern was used with no intentionally linear joining segments. The image resulting from this pattern had dramatically lower intensity rays. A pattern with semicircular elements had no diffraction-like rays. Yet another pattern made of elongated arcs had no diffraction-ray incidence. Moreover, another pattern made of stacked quarter-elliptical elements showed no diffraction-ray incidence; (5) Further tests showed that varying the linewidths between 10 microns and 30 microns made no difference in the effect. The effect was strongly related to the presence and predominant angular orientation of linear sub-elements within the resistance heating pattern; and (6) The predominance of the data showed the root cause of the effect and that the efficacy of many types of solutions were based on the understanding of root cause.
B. Illustrated Experimental Results
[0041] FIG. 2 illustrates the “star filter” effect that was referenced above. The photograph was acquired through a microwave heatable windshield sample from a Volkswagen vehicle design. As represented in the accompanying drawing, the microwires were arranged in parallel and were connected to a pair of bus wires that addressed the microwires with a controlled voltage. The effect is a negative factor with regard to marked penetration of heatable windshields. Through experimentation, it has been determined that the effect is primarily caused by the geometry of the repeating pattern. The width of the microwires was determined to be relatively unimportant, as was the color of the microwires.
[0042] The “star filter” effect is exhibited when a headlight or other bright point source is viewed in transmission in a darkened, night-like environment. In such a situation, the observer views a pair of extended rays emanating from the bright spot of the image.
[0043] In experimentation, copper-on-glass patterns were photolithographically formed. Two prior art patterns are shown in FIGS. 3 and 4 . In FIG. 3 , copper traces are arranged in parallel and are shown as being connected to one of the bus bars 20 . The copper traces may have a width of 10 or 20 microns and may have a spacing of 2.5 mm. In the pattern of FIG. 4 , the copper traces 22 are “wavy.” Each trace alternates between a constant radius arcuate sub-segment and a straight sub-segment. As in FIG. 3 , only one of the bus bars 24 is shown.
[0044] FIGS. 5-8 show photographs taken through windshields having a 45 degree tilt. In each case, the camera was approximately 18 inches from the windshield and was focused at infinity. The photographed vehicle was approximately 80 feet away.
[0045] In FIG. 5 , the photograph was taken through a “clear” region of the windshield. As can be seen, no “star filter” effect is evident. In comparison, FIG. 6 is a photograph through an array of straight traces, such as shown in FIG. 3 . With the straight-line pattern, a single pair of rays are predominant in emanating from the point source, oriented at an angle generally normal to the lines in the pattern. This is typical of a conventional diffraction grating.
[0046] In FIG. 7 , the photograph was taken through an array of “wavy” traces, such as the traces 22 shown in FIG. 4 . The “star filter” effect is similar to that of FIG. 8 , which was taken through “wavy” microwires which also included straight segments such as shown in FIG. 4 . Measurements of the angles of the linear segments in the simulated traces and the conventional microwire windshield show that these angles are normal to the angles of the emanating ray pairs and they are not the same. Comparing FIGS. 6, 7 and 8 , the effect seen with straight-line samples evidences the straightness of the elements contributes to the problem. The orientation dependency of the pair of rays on the angle of the straight segments in the “wavy” samples show that the predominant orientation of even small linear segments in a regular pattern is an important factor.
[0047] As a final illustration of the effect, FIG. 9 shows a photograph taken at the edge of the array of microwires, so that a portion of the image light is outside the array. As can be seen, the “star filter” effect is only predominant in the portion of the windshield that includes the microwires.
[0048] Thus, the problem was to design a heatable trace pattern with “parallel” resistance elements that reduce or eliminate the objectionable rays or “star filter” line image when viewed in nighttime point-source transmissive viewing conditions. The current invention addresses this problem by means of an improved design that eliminates or reduces the occurrence of angularly repeating linear elements or subelements within a field of resistive glazing heating elements, while maintaining the desired spatial density of the elements and the desired heating performance. The improved design uses predominantly curvilinear elements arrayed in a fashion so as to increase the angular dispersion of the subelements within the plane of the glazing, while still maintaining the desired element spatial density and heating performance.
[0049] FIGS. 10 and 11 illustrate two embodiments of the invention. In FIG. 11 , a serpentine quarter-arc pattern 26 of traces is shown. No portion of a trace is linear, since each trace is formed of a succession of quarter arcs. Similarly, there are no linear segments within the traces in the pattern 28 shown in FIG. 10 . FIG. 12 shows one period of a trace from the pattern of FIG. 10 . The trace 30 shown in FIG. 12 is a quarter-ellipse pattern. For purposes of explanation, a centerline 32 is shown in FIG. 12 . The distance from the centerline to each apex of the trace may be 1.0 mm, but this is not critical.
[0050] FIG. 13 shows a comparison of point source imaging through a conventional microwire (top image), through the serpentine quarter-arc pattern of FIG. 11 (lower left image), and through the quarter-elliptical pattern of FIG. 10 (lower right image). Using the patterns shown in FIGS. 10 and 11 , the “star filter” effect is significantly reduced or eliminated. By designing the trace pattern to reduce or eliminate a predominance of similarly oriented linear features, it is possible to develop a conductively heatable array with a much-reduced or zero instance of diffraction ray patterns.
[0051] While not limiting, other contemplated patterns are shown in FIGS. 14, 15 , 16 and 17 . The serpentine trace 34 in FIG. 14 is formed by attached semicircles. Thus, adjacent semicircles are on opposite sides of a centerline. In comparison, the trace 36 in FIG. 15 is one in which the semicircles are “stacked.” That is, each semicircle is on the same side of a baseline. In FIG. 15 , the trace 38 is formed of a succession of semi-arcs that have an angle of less than 90 degrees. A trace may also be formed of different non-linear elements. As one example, the trace 40 in FIG. 16 has a period formed of a semiarcuate segment, a semicircular segment, a semielliptical segment, and a quarter-arc segment.
[0052] There are also possibilities for forming traces that are defined by short, randomized linear elements. Because the orientation of the linear elements is non regular, the pattern is less susceptible to observation of the “star filter” effect. One embodiment is shown in FIG. 18 . In this illustrated embodiment, there are repeating patterns of randomly angular elements, so that the element orientations are not strictly random.
C. Quantitative Analysis
[0053] The microwire windshield prototype sample was analyzed visually and by spectrophotometer. The diffraction pattern can be described by considering grating theory. The basic equation of this theory is presented below.
sin θ m = sin θ i + m λ d
Here, the angles θ i and θ m are represented in FIG. 19 , m is an integer number, d is the period, and λ is wavelength. It is easy to see that diffraction angle θ m depends on wavelength λ. It explains the coloration of the image. Moreover, in the particular case, the ratio between wavelength and the period is very small,
λ d ~ 10 - 4
That is why it is difficult to see the separate diffraction spots. We instead see a line.
[0054] Simple observation based on the above grating theory and super-position principle for lamellar gratings yield to a structure which may have a halo round headlights in the imaging plane. For example, when a glass plate with water droplets was tested visually, only halo was observed. The randomness in position as well as the circular nature of the droplets contributes to a more uniform halo instead of diffraction in a particular direction.
[0055] Candidates for a wire structure, which should have halo round headlights in the imaging plane include those shown in FIGS. 10 and 11 , which were described above.
1. Quantitative Analysis of Diffraction Pattern of Conductive Metal Traces
[0056] Simplified problem. First we will use the superposition principle and will reduce the problem to the case of lamellar grating shown at FIG. 19 . Then, we assume that there are three major areas with respect to FIG. 19 : upper half space, y>a, with refractive index n 1 , lower half space, y<0, with refractive index n 2 , and modulated region, 0<y<a, with refractive index n(x, y). For each y, the function n(x, y) is a periodic function with respect to x, such that
k 2 ( x , y ) ≡ ( ω c n ( x , y ) ) 2 = ∑ j = - ∞ ∞ g j ( y ) exp ( ⅈ 2 π j d x ) ,
where d>0 is the period. For example, in the case of silver lamellar structure shown in FIG. 19 with refractive index nl=0.05−i*2.87 at wavelength 500 nm, we have
n ( x , y ) = { n 1 , m d + h / 2 < x < ( m + 1 ) d - h / 2 , n l , m d - h / 2 < x < m d + h / 2.
Here h is the wire width and m is an integer number. In this particular example, the refractive index of modulated area does not depend on y. Further, we assumed a monochromatic light source with incident angle θ 1 close to zero. Procedure of monochromatic light summation with photopic response curve will yield to a case of broadband light source.
[0057] Algorithm of Solution. We will use a standard solution of Maxwell equations for upper half space and for lower half space. The Maxwell equations for modulated area can be reduced to:
Δ E z +k 2 ( x,y ) E z ( x,y )=0
[0058] for TE polarization and
∂ H Z ∂ y = k 2 ( x , y ) E ~ x = 0 , ∂ E ~ x ∂ y = - H z - ∂ ∂ x ( 1 k 2 ∂ H z ∂ x ) = 0
for TM polarization. These equations can be further reduced to the ordinary differential equations if we use periodicity of the electric and magnetic fields with respect to variable x. Both TE and TM polarizations are important for the evaluation of the light transmittance in the considering problem because λ/d<<1.
[0059] Boundary conditions are the continuity conditions for tangential components of electric and magnetic field at the boundary y=0 and y=a. Finite difference method together with the conditions of continuity leads to an algebraic system of equations with respect to Fourier coefficients of electric (TE polarization) and magnetic (TM polarization) fields.
[0060] Relative intensity of the transmitted light in the diffraction pattern and its color distribution will result from this simulation of electric and magnetic fields.
2. Statement of the Mathematical Problem
[0061] Let us assume that the grating structure (see the example of the grating structure of FIG. 20 ) has d x period with respect to the x direction and d z period with respect to z direction; y-direction is a wave propagation direction. We consider a diffraction pattern produced by a plane wave with incident wavevector k 2 having the components
α 0 =0, β 0 =−k 0 , γ 0 =0,
and the polarization vector A orthogonal to the wavevector having components (see FIG. 19 )
A x =−sin δ, A y =0 , A z =cos δ
[0062] The incident electric field is chosen such that | A |=1V/m. Moreover, in the particular case the ratio between wavelength and the period is very small,
λ d x ~ λ d y ~ 10 - 4 .
Due to the x and z periodicity, the electric field in front of the glass with metal traces can be expressed by the sum of the incident electric wave and reflected waves
E _ ( x , y , z ) = E _ ( i ) + ∑ n = - ∞ + ∞ ∑ m = - ∞ + ∞ B _ n , m ( 2 ) exp [ ⅈ ( α n x + β n , m ( 2 ) y + γ m z ) ] ,
where
α n = 2 π n d x , γ m = 2 π m d z , β n , m ( 2 ) = k 0 2 - α n 2 - γ m 2 .
The transmitted electric field can be represented by the expression
E _ ( x , y , z ) ∑ n = - ∞ + ∞ ∑ m = - ∞ + ∞ B _ n , m ( 1 ) exp [ ⅈ ( α n x - β n , m ( 2 ) y + γ m z ) ] .
[0063] The similar equations apply to magnetic fields in front and behind the window with metal traces. Inside the modulated area (glass with metal traces) we have Maxwell equations [1, 2] with a periodic permittivity
ɛ ( x , y , z ) ∑ n = - ∞ + ∞ ∑ m = - ∞ + ∞ ɛ n , m exp [ ⅈ ( 2 π n d x x + 2 π m d z z ) ] .
[0064] Typical values for refractive indices of the aluminum and silver traces are shown in the Table 1.
TABLE 1 The refractive indices of aluminum and silver traces. Material 400 nm 500 nm 600 nm 700 nm 800 nm Aluminum 0.4 − I*4.45 0.667 − I*5.573 1.043 − I*6.568 1.55 − I*7.0 1.99 − I*7.05 Silver 0.075 − I*1.93 0.05 − I*2.87 0.06 − I*3.75 0.075 − I*4.62 0.09 − I*5.45
Based on this approach we can develop an algorithm for the diffraction pattern | E (x, y, z,)| 2 evaluation.
3. Experimental Setup
[0065] A simplified optical structure of an automotive headlight is shown at FIG. 21 . The typical testing distance from the headlight to the registration plane is about 25 meters. Required shape of directional lighting at the registration plane is presented in FIG. 22 .
[0066] A possible experimental setup for the testing of the glass/plastic plate with metal traces is shown at FIG. 23 .
[0067] It is important to differentiate the diffraction pattern from aperture and a pattern produced by the diffused light. For example, at FIG. 24 we have a “halo”, which is the result of the Fraunhofer diffraction only without any additional scattering effect. The standard requirements to automotive headlight limiting this type of diffraction “halo” should be adopted when determining the experimental setup. | In accordance with one approach to the invention, elements and sub-elements of a conductive pattern on or in an optical member are designed and arranged to be predominantly or exclusively curved, so as to control the appearance of ray-like disturbances during nighttime point-source viewing situations. In another approach, the sub-elements of the conductive pattern are designed and arranged so as to be a large number of short, linear or curved elements oriented with a large angular distribution. | 7 |
BACKGROUND OF THE INVENTION
The present invention relates to closure caps for sealing glass or plastic containers and more particularly to an improved composite closure cap having a metal cover and molded plastic container engaging ring. The metal cover and the plastic ring have tapered and engaging surfaces for a controlled closure cap removal torque.
Composite closure caps are well known and are widely used. They include a disc-like cover portion inserted into a circular molded plastic ring with the ring providing threaded or other means for attaching the composite cap to the container. A sealing gasket is provided on the metal cover and tamper indicating means are sometimes provided in the form of a vacuum indicator button on the cover with or without an additional tamper indicating band provided as a portion of the molded plastic ring.
While such composite closures have found acceptance in various packaging uses, including the vacuum packaging of food, prior composite closures have proven unsatisfactory for certain food packages where heat is applied during the sealing operations in retorting and otherwise. A serious drawback to certain of these prior closures has been a significant reduction in torque during the package handling and/or shelf life. The removal torque for the closure cap can become significantly reduced resulting in potential problems with consumer confidence and reduced resistance to abuse. Even where attempts have been made to increase this torque by the application of excess rotational force to the cap during application, the result has been creepage of portions of the plastic ring and container causing a loss of removal torque between the ring and threads and between the ring and the separate closure cover.
An object of this invention is to minimize this drop in removal torque by reducing the force in the plastic threads which cause it.
Other and further objects of the present invention will become apparent upon an understanding of the illustraive embodiments about to be described, or will be indicated in the appended claims, and various advantages not referred to herein will occur to one skilled in the art upon employment of the invention in practice.
BRIEF DESCRIPTION OF THE DRAWINGS
A preferred embodiment of the invention has been chosen for purposes of illustration and description and is shown in the accompanying drawings, forming a part of the specification, wherein:
FIG. 1 is a perspective view of a sealed container in accordance with the invention.
FIG. 2 is a perspective view illustrating an opened package.
FIG. 3 is an enlarged vertical sectional view of the package of FIG. 1.
FIG. 4 is an enlarged vertical sectional view of the closure cap and container before sealing.
FIGS. 5 and 6 are enlarged sectional views of the package top illustrating the cover in two differing sealing positions.
FIG. 7 is an enlarged perspective view illustrating the tapered portions of the cooperating plastic ring and cover.
FIG. 8 is a perspective view partially in section illustrating an embodiment of the closure including roughened and tapered torque control surfaces.
FIGS. 9 through 11 are fragmentary enlarged sectional views illustrating the sealing action at the top of the plastic ring and the outer edge of the cover.
Composite closures, as noted above, are in wide use particularly for sealing food packages. The following United States patents, for example, have been issued to the assignee of the present invention and these illustrate prior composite caps with a plastic sealing ring mounting a metal or plastic disc-like cover, i.e. U.S. Pat. No. 3,930,589 of Jan. 6, 1976; U.S. Pat. Nos. 3,913,772 and 3,913,771 both of Oct. 21, 1975.
DESCRIPTION OF THE PREFERRED EMBODIMENT
A preferred embodiment of the improved closure and package will now be described with particular references to the figures.
The closure 1 is applied to and seals a glass or plastic container 2. As illustrated in FIGS. 3 and 4, the molded plastic ring 4 is formed with a skirt portion 5 including inwardly directed threads 6 for engaging cooperating threads 7 at the container mouth. A radially inwardly directed flange 8 is formed at the top of the plastic ring 4. Together with the skirt portion 5 it forms a cover engaging corner with the inner edge 9 engaging and forcing the cover 10 into sealing engagement with the container rim 11. A tamper indicating band may form the lower portion of the plastic ring 4 and it is attached to the skirt portion 5 of the plastic ring 4 at a line of weakness as described in the above noted patents.
As illustrated at 12 in the figures, there is an inwardly and upwardly tapered surface near the top of the plastic band. Upon assembly of the closure 1, the cover 10 is inserted at the top of the ring 4 and the preferred embodiment of the cover 10 includes a downwardly facing gasket receiving channel 13 having a tapered radial outermost surface 14 shaped to conform to the ring taper for engagement therewith. The engaged surfaces 12 and 14 form a torque control means. The frictional engagement between these surfaces 12 and 14 upon closure cap application provides for a removal torque adjustment as will be described further below. Either the plastic surface 12 or the metal cover surface 14 or both may be roughened or scored as illustrated in FIG. 8 to increase the frictional engagement therebetween.
These engaged frictional surfaces 12 and 14 provide an adjustable amount of ring 4 retention torque which is set by controlling the sealing torque force during container sealing. The relative flared or "inclined plane" engagement between the cover and the plastic ring increases as the cap and the container threads draw the closure cap into sealing relation with the advantage resulting from the taper reducing the stress on the ring 4 threads 6. This is advantageous because the reduced thread and ring stresses permit them to remain in their original molded position without creepage during package storage and cause the removal torque as determined by the frictional engagement between the tapered surfaces to remain substantially constant and at the level obtained during the sealing.
FIGS. 6 and 7 illustrate a closure cap 1 including the ring 4 and the cover 10 in sealing positions. FIG. 5 illustrates a seal made to provide a low degree of closure removal torque so that the cover and the ring are not screwed fully down on the container and are relatively higher on the sealed package. Nevertheless, the relatively thick channel 13 with the sealing gasket 20 are fully engaged with the rim 11 to form an effective top and side seal. The downward force generated at the ring threads 6 has been transferred to the upper portion of the ring 4 including the ring edge 9 and the flared ring and cover torque control surfaces 12 and 14.
FIG. 6 illustrates a seal where the ring 4 has been turned further down on the container rim resulting in an increase in the amount of removal torque created between the taper surfaces 12 and 14. In this case the ring inner edge 9 flexes upwardly to accommodate the change in ring position and an excellent top and side seal results between the gasket 20 and the container rim 11.
FIG. 7 is an enlarged perspective view showing the rotation of the ring 4 on the container threads 7 and showing the ring inner edge 9 forcing the cover 10 into sealing position as an additional sealing and torque controlling force is generated between the engaged tapered ring and cover torque control surfaces 12 and 14.
FIG. 9 is an enlarged sectional view showing the engaged and roughened tapered portions 12 and 14 in the embodiment of FIG. 8 and illustrating the generation of the significant and controllable torque removal force between the two engaged and roughened surfaces 12 and 14. One or the other of these surfaces may be left smooth where a satisfactory friction force is generated by a single roughened surface.
Enlarged sectional views 10 and 11 illustrate differing angular positions of the tapered surfaces with respect to the container axis. FIG. 10 illustrates a relatively small angle A in a situation where a relatively low degree of stress is placed on the ring threads 6 when drawing the cover 10 into its sealed position as illustrated. This sharper angular relationship maximizes the more radially directed component of force between the plastic ring 4 and the cover 10 to provide a relatively high closure retention and removal torque while the low stress on the plastic threads minimizes plastic creep and unintentional closure loosening.
FIG. 11 illustrates a wider angle B providing for a minimized radially directed component of the force between the ring and the cover providing a still effective removal torque control without a significantly increased stress on the ring threads.
It will be seen that an improved composite closure is provided which provides a package with minimized creep in the plastic ring of the closure and with a predetermined torque control.
As various changes may be made in the form, construction and arrangement of the parts herein without departing from the spirit and scope of the invention and without sacrificing any of its advantages, it is to be understood that all matter herein is to be interpreted as illustrative and not in a limiting sense. | A composite closure cap is described comprising a molded plastic ring and a separate disc-like cover. The cover includes a gasket for sealing. Tapered friction surfaces on the plastic ring and on the cover interact to provide for the control of the closure cap removal torque. | 1 |
BACKGROUND OF THE INVENTION
This invention concerns the introduction of fluids into a system without microcontaminants entering the fluid flow. More particularly, the invention relates to a fluid dispensing and metering unit which can be combined with other similar units to create a flow control manifold. The flow control manifold provides for the addition of a variety of different fluids into a single, clean continuous duct.
In the course of manufacturing wafers for integrated circuits, the wafers are rinsed with various chemicals and deionized water for coating, etching and cleaning processes. It is of the utmost importance that these fluids are applied to the wafers in a very clean state, absent contaminants that may reside in the fluid conducting system. Possible contaminants include residual fluids that previously passed through the system and microscopic particles of grease, dust and metallic particles generated from individual pieces of the fluid conducting system rubbing against each other. If such contaminants are inadvertently sprayed onto the wafers, the potential utilization of the wafer for the construction of an integrated circuit may be significantly decreased. For example, the presence of residual fluids could chemically effect subsequent processing steps of the wafer.
To prevent even microscopic particles from entering the fluid flow, thorough rinsing of the fluid delivery system must be performed between processing steps. The optimum means for conducting such a thorough rinsing would have a minimum surface area and would eliminate areas in which particle accumulation is likely. For example, previous fluid delivery systems have included threaded connection surfaces. The hollow between each individual thread can hold minute amounts of contaminants. Complete rinsing of each hollow is a very difficult task. Other prior assemblies have used numerous strands of tubing to deliver each particular fluid into the delivery system. Such a system generally has more joints and surfaces for contaminants to reside, making flushing of the system less thorough and more time consuming.
SUMMARY OF THE INVENTION
We have now developed a device having a generally small surface area for rinsing which supplies a very clean fluid flow for the manufacture of wafers. At the same time, the unit both precisely meters and dispenses the various fluids.
Briefly, the invention first consists of a single fluid dispensing and metering unit. This unit is generally a block having a proximal and distal face. A fluid conducting duct runs through the block from the proximal to the distal face. Located generally above this duct is the dispensing portion of the invention. An aperture in the fluid conducting duct communicates with this dispensing portion.
A very flexible bellows is mounted on the block to create a fluid tight cavity between the block and the bellows. The bellows has a tip which lies in the aperture and extends into the fluid conducting duct. The chosen fluid travels through a fluid port into this fluid-tight cavity. A housing having a hollow cavity is mounted above the bellows to form a chamber between the housing and the bellows. A passageway exists between the hollow cavity and the bellows chamber. Springably mounted in the hollow cavity is a piston. The piston extends through the housing passageway into the bellows chamber where it threadably engages the bellows.
When the piston is retracted, the bellows is drawn toward the housing, removing the bellows tip from the aperture. Withdrawal of the bellows tip allows fluids residing in the fluid cavity to pass into the fluid conducting duct. Piston retraction can be affected by air pressure working on the spring holding the piston. Controlling the timing and amount of air pressure is a means to meter the amount of fluid dispensed.
A second feature of the invention involves aligning a plurality of these fluid dispensing units so that a single continuous fluid duct is obtained. In this way, various fluids for processing the wafers can be dispensed into a single duct. Utilization of a single fluid duct minimizes the surface area of the fluid delivery system to be rinsed. The particular structure of this invention also maximizes the thoroughness of the rinsing process to ensure a cleaner fluid flow. Other advantages of the invention will become apparent to those skilled in the art from the following detailed description of the preferred embodiment when considered in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a sectional side elevation of the fluid dispensing and metering unit of the present invention in the closed position;
FIG. 2 is a the view of FIG. 1 in the open position;
FIG. 3 is a top plan view of the individual units of the invention aligned to form a single continuous duct shown shortened on the longitudinal axis; and
FIG. 4 is a front elevational view of the unit taken along line 4--4 in FIG. 1.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings, FIG. 1 shows a sectional side elevation of a single fluid dispensing and metering unit, referred to generally as 10. The unit generally consists of a block 12 having a proximal face 14 and a distal face 16. A fluid conducting duct 18 extends from the proximal face 14 to the distal face 16 communicating with the area external to the block at both faces. Suitable materials for the block composition include synthetic resins that are heat, chemical and pressure resistant. The block is preferably constructed of PTFE. Alternatively, PVDF and PFA may be used. PTFE is a common and well known acronym for polytetrafluorethylene. PVDF is a common and well known acronym for polyvinylidenefluoride. PFA is a common and well known acronym for penfluoroalkoxy. To dispense the desired fluid into the duct 18, a dispensing means, generally shown as 20, is connected to the block 12. The dispensing means 20 extends into the fluid conducting duct 18 and is located generally intermediate to the proximal block face 14 and the distal block face 16.
In the preferred embodiment the dispensing means 20 has a flexible bellows 22 mounted on the block 12 to create a fluid-tight cavity 24. An 0-ring 68 lying between the bellows 22 and the block 12 is used to enhance the fluid-tight seal. The bellows 22 is preferably constructed of PTFE for flexibility. Other suitable materials include PFA. The created fluid-tight cavity has an aperture 26 leading into the fluid conducting duct 18. When the unit of the present invention is in the closed position as shown in FIG. 1, a tip portion 28 of the bellows 22 sealingly engages the aperture 26 as it extends into the fluid conducting duct 18. The fluid to be dispensed enters the fluid-tight cavity 24 through a fluid port 30. The fluid port externally engages a fluid source. When the bellows tip portion 28 engages the aperture 26, the fluid entering the fluid-tight cavity 24 cannot enter the fluid conducting duct 18.
Mounted above the bellows 22 is a housing 32. This configuration creates a sealed chamber 34 between the housing 32 and the bellows 22. The housing 32 has a hollow cavity 36 with a proximal cavity end 38, a distal cavity end 40 and interior walls 86. Preferably, the distal end 40 includes a housing cap 82 having a vent 84 that threadably engages the body of the housing 32. A passageway 42 exists between the hollow cavity 36 and the bellows chamber 34. Springably mounted on the distal end 40 of the hollow cavity 36, by a rate spring 46, is a piston 44. The piston 44 has a longitudinal shaft 48 held in a fluid-tight relation within the housing passageway 42 and partially extending into the bellows chamber 34 to threadably engage the bellows 22. A larger diameter portion 50 of the piston 44 abuts the interior walls 86 of the hollow cavity 36, dividing the hollow cavity 36 into an upper 52 and lower 54 hollow cavity portion. A fluid-tight seal exists where the larger diameter piston portion 50 engages the hollow cavity 36 of the housing 32. Preferably, the piston is made of PVC.
The unit is also provided with a modulating means, generally referred to as 56. This modulating means precisely meters the amount of fluid that is dispensed into the fluid conducting duct 18. In the preferred embodiment the modulating means 56 includes a metering passageway 58 having a proximal 60a and a distal 60b end. The metering passageway 58 extends from outside the housing 32 to the lower hollow cavity portion 54. The proximal end 60a is adapted for receiving a fluid flow source, such as an end of tubing. Preferred fittings include nozzles and barbs. FIG. 1 shows a barb 70 as a preferred adaption.
FIG. 2 depicts the fluid dispensing unit of the present invention in the open position. This position is obtained by forcing a fluid through the metering passageway 58 of the modulating means 56. The preferred fluid is air, but other fluids such as water are also possible. The fluid enters into the lower portion 54 of the hollow cavity 36 from the metering passageway 58 to force the piston 44 toward the distal end 40 of the hollow cavity 36. Retraction of the piston 44 in this manner, draws the bellows 22 toward the housing 30 removing the bellows tip portion 28 from the aperture 26. Fluid 72 can now pass from the previously fluid-tight cavity 24 into the fluid conducting duct 18.
Reversing the pressure on the metering passageway 58 withdraws the fluid from the lower portion 54 of the hollow cavity 36. In response, the piston 44 moves toward the proximal cavity end 38. The bellows 22 returns to a relaxed position with the bellows tip portion 28 again engaging the aperture 26. This is the closed position of FIG. 1 preventing the flow of fluids into the fluid conducting duct. By controlling the amount of pressurized fluid entering the metering passageway and the length of time the piston is retracted, one can regulate the amount of fluid to dispense into the fluid conducting duct.
FIG. 3 illustrates the flow control manifold of the present invention, generally referred to as 74. The flow control manifold 74 consists of a plurality of fluid dispensing units 10 aligned so that the individual fluid conducting ducts 18 of each fluid dispensing unit 10 forms a single continuous duct 62. The units 10 are in sealing engagement with the distal face 16 of each unit 10 engaging the proximal face 14 of the neighboring unit 10. As shown in FIG. 3, the units are joined by two tie bolts 76 which penetrate the series of blocks. These bolts are protected from any corrosive action of the dispensed fluids by means of 0-rings 78 and protective end caps 80.
FIG. 3 also shows that a fluid-tight seal preferably exists where the individual fluid conducting ducts 18 meet to form the single duct 62. Referring back to FIG. 1, in the preferred embodiment the seal is created by a recess 64 in the distal block face 16 of a larger diameter than and coaxial with the fluid conducting duct 18. An 0-ring 66 sits in this recess 64. When the distal block face 16 of the first unit engages the proximal block face of a second unit, this construction creates a fluid-tight seal around the connection between the fluid conducting ducts 18.
FIG. 4 shows the flow control manifold of FIG. 1 through line 4-4. Of particular interest is the intrusive nature of the 0-ring 66 and the bellows tip portion 28 into the fluid conducting duct 18. Such an intrusion is desirable because positive features are easier to rinse of contaminants than negative features.
While a specific embodiment of the invention has been shown and described in detail to illustrate the application of the inventive principles, it will be understood to those skilled in the art that the invention may be embodied otherwise without departing from such principles. | A fluid dispensing and metering unit is described for dispensing fluids into a system without the introduction of microcontaminants into the fluid flow. This unit includes a block with a fluid conducting duct axially extending from the block's proximal face to the block's distal face. In communication with the fluid conducting duct is a combined dispensing and modulating means for regulating the amount of fluid entering the fluid conducting duct. A plurality of these units can be assembled to construct a flow control manifold, creating a single continuous duct for carrying all dispensed fluids. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates generally to a soil sampling tool, and particularly to a hand operated soil sample core extraction tool such as used by farmers to take samples of soil in order to determine the composition of the soil.
2. Description of the Prior Art
Many serious back injuries have resulted from "pulling" a soil probe. With a conventional probe handle and rod combination the handle becomes closer to the ground with each successive section of the core that is pulled. The force required to pull the core can be more than 300 pounds, with the average being about 80 to 90 pounds. Man can most safely produce the greatest lifting force in the final 15° of leg extension.
A soil sampling tube fitted with a conventional rod and handle is forced into the ground by pushing downward on the handle. Shoulder, wrist, and arm injuries can result particularly when working with hard ground conditions.
U.S. Pat. No. 2,891,812, issued June 23, 1959 to L. W. Gourley, sets forth a soil sampling device provided with a section of pipe having affixed thereto a handle, a probe, and a footstep disposed for facilitating insertion of the probe into soil being sampled. A second pipe is slidably disposed on the first pipe and is provided with a lower section which facilitates removal of a sample from the probe. Insertion of the lower section is carried out by use of a second footstep attached to the second pipe. The device disclosed in U.S. Pat. No. 2,891,812, however, is directed to the problems of driving a sampling probe a short distance into hard ground and obtaining accurate core samples, and fails to approach the problem of eliminating the long arm and leg extensions encountered when "pulling" a conventional soil probe.
I am aware of the following patents that may be pertinent to the invention:
______________________________________684,010 A. Thalheimer Oct. 8, 19011,548,865 G. F. Bull Aug. 11, 19252,531,297 J. J. Rose Nov. 21, 19502,957,722 D. Ferraro Oct. 25, 1960______________________________________
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a soil sample core extraction tool which eliminates bending over to "pull" the core out of the ground.
It is another object of the present invention to provide a footoperated soil probe wherein the distance from the handgrip of the probe to the footstep thereof is constant and is such that full body weight can be safely applied to the footstep.
It is yet another object of the present invention to provide a soil sample core extraction tool provided with a special cleaning device which facilitates extraction of a sample from the tool and subsequent washing and lubricating of the probe in order to facilitate reinsertion of the tool into soil to be sampled.
These and other objects are achieved according to the present invention by providing a soil sample core extraction tool having: a handle member; a soil probe member movably mounted on the handle member; and a clutch disposed for selectively preventing movement of the soil probe member with respect to the handle member and realize, by sequential actuation and release of the clutch, movement of the handle member relative to the probe member in order to permit the operator of the tool to manipulate the handle member from a convenient position during the entire sampling operation.
The clutch is preferably mounted on the handle member and includes a pressure element mounted for rocking movement relative to the shaft of the soil probe member and provided with a through hole receiving the shaft. According to an advantageous feature of the present invention, the diameter of the hole provided in the pressure element decreases from opposed surfaces of the pressure element to a throat substantially midway between the surfaces in order to form a pair of oppositely directed, substantially coaxial frustoconical shaft-engaging surfaces joining at a transition zone and grippingly engaging the shaft whenever the pressure element is rocked to soil probe push-and-pull modes wherein a portion of each shaft-engaging surface contacts the shaft. Accordingly, the clutch is in neutral mode whenever the shaft-engaging surfaces of the pressure element contact the shaft substantially only at the transition zone joining the shaft-engaging surfaces to one another.
An extension is advantageously provided on the pressure element so as to form a footstep facilitating positioning of the pressure element during neutral and push modes. Further, a resilient element can be disposed between the handle member and the pressure element for biasing the pressure element toward its pull mode.
The soil probe member is generally provided with a sampling tube for obtaining the soil sample being sought. A cleaner according to the present invention is removably mounted on the handle member, and includes a handle and a cleaning head connected to the handle, with the cleaning head comprising a first disc-shaped part arranged for being pulled along the length of a sample receiving trough provided in the sampling tube, a second disc-shaped part for removing the end core form an end bore of the sampling tube, and a U-shaped part provided with absorbent material for applying a thin film of lubricant to the trough with a leg of the U-shaped part and to the outside of the sampling tube with the bight portion of the U-shaped part of the cleaning head. In this manner, the core sample can be efficiently extracted from the sampling tube, and the tube quickly cleaned and lubricated even in the field, for further sample taking.
These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view showing a soil sample core extraction tool according to the present invention.
FIG. 2 is an enlarged, fragmentary, vertical longitudinal sectional view showing details of the tool of FIG. 1.
FIG. 3 is a sectional view taken generally along the line 3--3 of FIG. 2.
FIGS. 4 through 9 are schematic diagrams showing the various steps in obtaining core samples with an extraction tool according to the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now more particularly to FIG. 1 of the drawings, a soil sample core extraction tool 10 according to the present invention comprises a handle member 12 and a soil probe member 14 movably mounted on handle member 12. More specifically, soil probe member 14 includes a shaft 16 slidably disposed in a longitudinal socket provided in handle member 12. Also illustrated as mounted on handle member 12 is a clutch 18 arranged for selectively engaging and releasing shaft 16 of member 14 and preventing movement of member 14 with respect to the handle member 12. Removably attached in a conventional manner, as by the illustrated screw threads (FIG. 2), to the lower end of shaft 16 is a substantially cylindrical sampling tube of one configuration which may be employed with a tool according to the present invention.
Removably mounted on handle member 12 is a sampling tube cleaner 22 which includes a handle 24 and a cleaning head 26 connected to handle 24. Head 26 comprises a first disc-shaped part 28 arranged for being pulled along the length of a trough 30 formed in sampling tube 20 by a hollow, cylindrical interior 32 and a longitudinally extending opening 34 communicating with the interior 32. A second disc-shaped part 36 is also provided in head 26 for removing the end core of the sample taken from the open end 38 of tube 20, while a U-shaped part 40 provided with absorbent material such as a sponge rubber or gauze padding, facilitates the application thereto of a thin film of lubricant. More specifically, the lubricant is provided to trough 30 as by a leg 42 of part 40, while the outside of tube 20 receives lubricant from the bight 44 of part 40.
A substantially C-shaped clip 46 is affixed to handle member 12 and provided with forked leg portions in order to receive the handle 24 of cleaner 22 and removably mount cleaner 22 on member 12 for storage and caring purposes when cleaner 22 is not being used.
Handle member 12 includes a longitudinal element 48 having affixed thereto at one end thereof a crossbar 50 forming a T-shaped handle member. The clutch 18 can be seen from FIG. 1 to be mounted at the other of the ends of longitudinal element 48.
Referring now to FIGS. 2 and 3 of the drawings, longitudinal element 48 can be seen to be provided with a longitudinal socket 52 in which is disposed the shaft 16 of soil probe member 14 for sliding movement with respect to longitudinal element 48.
Clutch 18 includes a pressure element 54 having opposed generally planar surfaces 56 and 58 and mounted for rocking movement relative to shaft 16. Provided in element 54 is a through hole 60 receiving shaft 16 and having a diameter which decreases from surfaces 56 and 58 to a throat 62 substantially midway between the surfaces 56, 58. In this manner, hole 60 forms a pair of oppositely directed substantially coaxial frusto-conical shaft-engaging surfaces 64 and 66 joining at a transition zone. These surfaces 64, 66 cooperate to engage shaft 16 whenever the pressure element 54 is rocked to soil probe push-and-pull modes wherein a portion of each shaft-engaging surface contacts shaft 16. Further, surfaces 64, 66 release shaft 16 in a neutral mode of clutch 18 whenever surfaces 64, 66 contact the shaft substantially only at the transition zone joining surfaces 64 and 66. The "pull" mode is illustrated in FIG. 2 of the drawings, while it will be appreciated that the "push" mode would be the extreme opposite position of pressure element 54 and the neutral model will be in-between these two extreme positions.
Clutch 18 further includes a bracket 68 of substantial "U" configuration and provided with a cantilever. Bracket 68 is affixed on the other of the ends of the longitudinal element 48, and pressure element 54 is retained in bracket 68 by cantilever 70, with cantilever 70 forming a fulcrum for a rocking movement of pressure element 54 relative to shaft 16. In other words, the coaction of pressure element 54 with shaft 16 and cantilever 70 will limit movement of pressure element 54 relative to longitudinal element 48.
An extension 72 is provided on pressure element 54 for forming a footstep facilitating positioning of pressure element 54 during the neutral and push modes of clutch 18. As will be appreciated, only a slight foot pressure need be exerted on the extension 72 in order to hold pressure element 54 in the neutral position against the bias of a, for example, compression spring 74 disposed between longitudinal element 48 and pressure element 54 for biasing pressure element 54 toward the pull mode.
Preferably, bushings 76 and 78 are fitted within socket 52 for guidingly receiving shaft 16, and the one end of spring 74 is disposed abutting the lower bushing 78 in order to exert the desired bias against pressure element 54.
The operation of tool 10 will now be discussed in conjunction with FIGS. 4 through 9 of the drawings.
Tool 10 is first steadied in a nearly vertical position by grasping crossbar 50 with both hands, not shown. Sampling tube 20 is now forced into the soil S to be sampled by stepping firmly on the extension 72 as shown by the arrow in FIG. 4. Sampling tube 20 will be pushed into the soil to the depth indicated in broken lines in FIG. 4, and subsequently removed from the ground by pulling upward on crossbar 50. Sampling tube 20 is now emptied and cleaned and reinserted into the soil as shown in FIG. 5 until extension 72 is within, for example, an inch or two of surface S. Now, while maintaining a slight pressure on extension 72, pull upward on cross bar 50 until extension 72 has been elevated to, for example, six to eight inches above surface S. Continue to maintain a slight upward pressure on crossbar 50 and step downward on extension 72. The latter now grips shaft 16 and the sampling tube 20 can be pushed into the soil until extension 72 is within, for example, one or two inches of surface S. See FIG. 6.
The steps set forth above as shown in FIGS.5 and 6 of the drawings are repeated, as shown in FIGS 7 and 8, until sampling tube 20 is full of soil being sampled. The depth of penetration of sampling tube 20 can be determined by the position of the end of shaft 16 which can be seen through the viewing holes 80 (FIG. 1) provided in the side of longitudinal element 48, which can be of the illustrated square cross secion. It is important not to push sampling tube 20 into the soil to a depth that exceeds its holding capacity as this jams the sample and can make removal from the ground extremely difficult.
Now remove the full sampling tube 20 by lifting upward on crossbar 50 as shown in FIG. 7. After the sampling tube has been elevated six to eight inches, for example, push downward on crossbar 50 returning extension 72 to within one or two inches of the surface S.
Sampling tube 20 can now be emptied and cleaned, and the abovedescribed steps as set forth in FIGS. 5 through 9 can be repeated until a desired depth of sample is reached.
Proper cleaning of sampling tube 20 ensures two things: (1) greatly reduced lifting pressures; and (2) a better soil core.
When cleaning sample tube 20, first clear trough 30 by inserting part 28 into the exposed sample and pulling part 28 along the length of trough 30. Second, remove the end plug from the sampling tube by placing part 36 over the end of the plug and pulling on the handle 24 of cleaner 22 in order to push the core from end 38 of tube 20.
Third, after sampling tube 20 is clear of soil, use part 40 as follows: apply a thin film of vegetable oil to the inside of the sampling tube 20 using a leg 42 of part 40, and use bight 44 of part 40 to apply a thin film to the outside of tube 20. Work a film of oil into the tip using one's fingers. The sponge, and the like, which is advantageously covered with a nylon or similar mesh, should be filled with vegetable oil each day. Vegetable oil is recommended because it is harmless to the skin and washes off easily with soap and water. Once every week or two, the sponge should be washed thoroughly using a liquid detergent.
As can be readily understood from the above description and from the drawings, a core extraction tool according to the present invention provides a simple yet efficient and safe mechanism for quickly and easily extracting accurate core samples.
The foregoing is considered as illustrative only of the principles of the invention. Further, 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, and accordingly all suitable modifications and equivalents may be resorted to, falling within the scope of the invention. | A sampling tube cleaning device adapted for removable mounting on a soil sample core extraction tool, the tube cleaning device including a handle portion and a cleaning head connected to the handle portion, the cleaning head further comprising a first cleaning member arranged for being pulled along the length of the trough of a sampling tube, and a second cleaning member arranged for removing the end core from a sampling tube and in a preferred emobodiment the cleaning head also has a U-shaped part provided with absorbent material for applying a thin film of lubricant to the trough of the sampling tube as well as the outside of the sampling tube to provide both a lubricant and cleaning function to the sampling tube to facilitate ease of operation in subsequent uses. | 4 |
TECHNICAL FIELD
The present application relates to lighting and plumbing fixtures, such as faucets and lamps.
BACKGROUND
Nightlights are sometimes used in bedrooms or bathrooms to faintly illuminate the rooms at night. Often such lights are not built into a house, however, because of the limited space for light fixtures, and are instead provided by plugging a lamp into a power outlet.
The beauty of light playing with water is well known, as are lighted fountains and showers. Toward this end, U.S. Pat. No. 6,126,290 to Veigel discloses a water draining fixture having a centrally disposed light distributor that is surrounded by water jets, so that the light shines through the water for a pleasing effect. Veigel states that an advantage of this configuration is that a light distributor can be removed and cleaned of calcium deposits, as opposed to a prior patent (WO 95/29300) that veigel states has light fed through a transparent window into the water flowing through the fixture head.
While these patents offer fixtures that illuminate flowing water, neither is optimized for providing lighting or decoration whether the water is flowing or not.
SUMMARY
In one embodiment a plumbing fixture for supplying water to a basin is disclosed that has a spout containing a water conduit, and a handle connected to a valve to control water flow through the water conduit, wherein at least one of the handle and the spout has a base region to hold the fixture adjacent to the basin, the base region containing a lamp, the lamp emitting visible light. For example, the plumbing fixture may be a faucet that is attached to a sink or countertop at a base that also serves as a source of visible light, providing a pleasing aesthetic effect. Separate bases for faucet handles and a faucet spout can be illuminated individually or as a group. A faucet spout and/or handle trim can be made of translucent or transparent material (e.g., acrylic, glass, crystal, etc.) that captures and redirects light from the base. The faucet light or lights can also serve as a nightlight for a bathroom, kitchen, laundry or bar, saving the space that a separate nightlight would require. In another embodiment a light is provided in a faucet spout, which can illuminate a sink for a pleasing effect, and can also serve as a nightlight. The spout can be translucent, carrying light as well as water from its base.
DESCRIPTION OF THE FIGURES
FIG. 1 is a perspective view of a sink with a faucet spout and handles attached at a base that includes a lamp.
FIG. 2 is an exploded perspective view of one of the handles of FIG. 1 .
FIG. 3 is a perspective view of a faucet handle having a metal ring disposed at the base, with light emitted from an upper surface of a lamp.
FIG. 4 is a perspective view of a faucet handle having a metal ring disposed at the base, with light emitted from an outer surface of a lamp.
FIG. 5 is a perspective view of a faucet handle having a metal ring disposed at the base, with light emitted from an outer surface of a lamp that fits within the ring.
FIG. 6 is a perspective view of a lamp that fits near a base of a faucet spout, the lamp including a plurality of light sources embedded in a translucent block.
FIG. 7 is a perspective view of a lamp including a plurality of light sources attached to a substrate encircled by a translucent block.
FIG. 8 is a perspective view of a lamp including a plurality of light sources attached to a substrate that fits beneath a translucent block near a base of a faucet spout.
FIG. 9 is a perspective view of a faucet having a substantially unitary body with a lamp disposed near an aerator of a spout.
FIG. 10 is a cross-sectional view of the spout of FIG. 9 with the lamp and aerator attached.
FIG. 11 is a cross-sectional view of the lamp and aerator of FIG. 10 .
FIG. 12 is a perspective view of a translucent faucet spout with a lamp disposed near the base to illuminate the spout.
FIG. 13 is a perspective view of a faucet spout with a translucent shroud disposed near the base to provide illumination.
FIG. 14 is a perspective view of a faucet spout with a shroud disposed near the base to illuminate the base.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 shows a plumbing fixture such as a faucet 20 for supplying water to a basin such as a sink 25 , the faucet attached to a countertop 22 and the sink. The faucet includes a spout 27 , a right handle 30 and a left handle 33 . The spout 27 has a base 35 that is attached to the countertop 22 , and the handles 30 and 33 each have a base 31 and 32 that are attached to the countertop. The handles 30 and 33 also each have a shroud or body 38 and 39 that is disposed adjacent to the respective bases 31 and 32 . A stop 40 is positioned at the bottom of the sink 25 to control water flow out of the sink. Although difficult to represent in this drawing, bases 31 , 32 and 35 are each illuminated, providing a pleasing aesthetic effect.
FIG. 2 is an exploded view of the left handle 33 as it is being attached to the countertop 22 or sink 25 through an aperture 42 . The handle is 33 may be shaped in many different styles, only one of which is shown. A light source such as a lamp 44 includes a plurality of light-emitting diodes (LEDs) 46 that are affixed to an annular substrate such as a circuit board. A lead wire 45 provides electricity for the LEDs 46 through a plurality of wires that are attached to the substrate 44 . The base 32 in this embodiment is made of a translucent material such as acrylic, plastic, glass, crystal, etc., and may act as a lamp shade, lens or surface. As with other embodiments, the translucent material may be transparent, frosted, colored, patterned, etc. Also, the base may have opaque as well as translucent areas, and may be perforated, filigreed, laser etched or otherwise patterned.
A hot water inlet conduit 48 and a hot water outlet conduit 50 protrude through the lamp 44 and aperture 42 , with fluid communication between the conduits 48 and 50 controlled by a valve that is connected to the handle 33 within the body 39 , as is conventional. A threaded fitting 52 provides an attachment for a nut, not shown, to clamp the body 39 to the countertop 22 , thereby fastening the plumbing fixture 20 to the sink area. The base 32 may be pressed directly against the countertop with sealant such as silicone rubber in this embodiment, although a waterproof gasket may also be interposed between the base 32 and the countertop or the substrate may also serve as such a gasket. Instead of mounting on a countertop or sink, the fixture can be mounted on a basin, tub, shower, etc.
In FIG. 3 a metal ring 55 is clamped between the translucent ring 32 and the countertop 22 , with the light emitting from an upper surface of the translucent ring 32 . Instead of the ring 55 being made of metal, the ring 55 may be made of other materials such glass, acrylic, plastic, etc.
FIG. 4 shows an example in which the metal ring 55 is clamped between the translucent ring 32 and the countertop 22 , with light emitting from a side surface of the translucent ring 32 . Instead of the ring 55 being made of metal, the ring 55 may be made of other materials such glass, acrylic, plastic, etc.
In FIG. 5 the translucent ring 32 fits within and protrudes above the metal ring 55 . The metal ring 55 is clamped between the translucent ring 32 and the countertop 22 , with the light emitting from a side surface of the translucent ring 32 . Instead of the ring 55 being made of metal, the ring 55 may be made of other materials such glass, acrylic, plastic, etc.
Although depicted in FIG. 1 – FIG. 5 as having a smooth surface to facilitate illustration, the translucent ring 32 can have an etched, grooved, corrugated or otherwise uneven surface that refracts light in various patterns. Such an uneven surface can also be formed on an inner surface of the translucent ring 32 , for example as a pattern of V-shaped grooves. Such grooves can act as a prism that separates white light into different colors. Also possible is a translucent ring that has metal strips, flakes or other patterns spaced about its periphery.
FIG. 6 shows a lamp 100 including a translucent substrate 101 that includes at least one light source embedded in the substrate, the substrate 101 designed to fit near a base for a faucet spout. The lamp 100 is turned upside-down from its normal operating orientation to display the integration of the light source into the substrate 101 . The substrate 101 is generally ring-shaped and has a pear-shaped aperture 103 near its center to allow a water conduit and rod for a sink stop to pass through, neither of which is shown in this figure. Other shapes for the substrate 101 and aperture are alternatively possible. An insulated electrical lead 105 , a cutaway portion of which is shown, connects the light source with a power source, not shown. A plurality of LEDs 110 are disposed in holes in the substrate 101 and are connected to the lead 105 with wires fitting in grooves 112 in the substrate. Light is emitted from the lamp 100 along outer and bottom surfaces of the substrate 101 (in operation from outer and upper surfaces), depending upon which of those surfaces are exposed.
The LEDs 110 may be white or colored, and typically the electricity supplied by the lead 105 is both low voltage and low current, for low power consumption and low risk of shock. For example, the lead 105 may provide direct current of 0.05 to 0.15 amperes at a voltage of between about 2 and 5 volts. A transformer may be provided, not shown, that converts alternating household current of 120 volts to that needed for the LEDs 110 . The transformer may be connected to a ground fault circuit interrupter (GFCI) outlet to further reduce risks.
In FIG. 7 a lamp 120 is shown including a translucent ring 121 that surrounds a substrate 122 holding at least one light source, the ring and substrate fitting near a base for a faucet spout or handle. The substrate 122 has an aperture to allow a water conduit and rod for a sink stop to pass through, or to allow a pair of water conduits to pass through. An insulated electrical lead 125 , a cutaway portion of which is shown, connects the light source with a power source, not shown. A plurality of LEDs 130 are affixed to the substrate 122 and are connected to the lead 125 with wires attached to the substrate. Light is emitted from the lamp 120 along outer and upper surfaces of the ring 121 , depending upon which of those surfaces are exposed. For example, FIG. 5 illustrates a situation in which primarily the outer surface of translucent ring 32 emits light.
FIG. 8 shows a faucet lamp 150 in which a translucent block 151 is disposed adjacent a substrate 155 holding a plurality of light sources 152 , the block and substrate designed to fit near a base for a faucet spout or handle. The lamp 150 is turned upside-down from its normal operating orientation to display the light sources 152 and substrate 155 that shine light up through the block during operation. The block 151 has a pear-shaped aperture 153 near its center to allow a water conduit and rod for a sink stop to pass through, neither of which is shown in this figure. An insulated electrical lead 152 , a cutaway portion of which is shown, and a plurality of wires 158 connect the light sources 152 with a power source, not shown. The light sources 152 may be LEDs, the base of which is shown, with the wires depicted in exaggerated fashion to facilitate illustration. Light is emitted from the lamp 150 along outer and upper surfaces of the block 151 , depending upon which of those surfaces are exposed. For example, FIG. 2 illustrates a situation in which primarily the upper surface of translucent ring 32 emits light that is visible outside the faucet. Note also that each of the embodiments discussed so far is generally removed from contact with water so that calcium deposits or other water stains are not a problem.
FIG. 9 shows a faucet 200 having a substantially unitary body 201 that includes a spout as well as handles 205 , one of which is hidden from view. A lift rod 208 for a sink stop is also partly hidden from view by the spout 202 . An aerator 211 is attached to the spout 202 with a light-emitting block 212 fitted around the aerator and within the spout 202 . A base 220 for the faucet 200 may also act as a lamp, much as described before.
As shown in FIG. 10 , block 212 is a translucent ring that is seated atop light source 215 . Referring also to FIG. 11 , translucent ring 212 is attached to the aerator 211 , which has a threaded portion 215 for attachment to spout 202 . The spout 202 is formed of an exterior wall 218 , and has a water conduit 228 into which the threaded portion 215 is screwed. Alternatively, the block 212 may be affixed or threaded to the faucet and the aerator 211 screwed or attached to the block. In another embodiment, the block 212 and/or aerator 211 may be affixed to the faucet by a twist and lock mechanism that may be employed sometimes for commercial applications. Light source 215 may be a ring-shaped substrate holding at least one LED as described above, with an electrical lead 225 providing power to the light source 215 . The light-emitting block 212 provides illumination to a sink or other basin that the block faces, accentuating the basin, which can appear to glow. Although a unitary faucet is shown, a separate spout can also hold a light source near the aerator. Note also that this embodiment may contact water, but the light-emitting block 212 can be easily removed for cleaning.
FIG. 12 shows a faucet spout 300 including a body 303 that is made entirely of translucent material, such as acrylic, plastic, glass, crystal, etc., which may be clear, frosted or colored. The body 303 encircles a water conduit 305 that provides fluid communication between a base 308 of the spout and an aerator 310 . The base 308 is attached to a threaded portion 311 that fits through a hole in a sink top or countertop, not shown in this figure. A light source 313 fits around the threaded portion 311 and beneath the base 308 to illuminate the spout 300 . The light source includes a substrate 315 that holds a number of LEDs 320 , each of which is connected to an electrical lead 318 .
The body 303 has an index of refraction that is greater than that of the air, and so some of the light from the light source 313 flows through the gently curving body to exit near the aerator 310 . Stated differently, the body 303 forms a conduit for both water and light. When water flows through the water conduit 305 light may also flow through the water to exit at the aerator 310 , which may also be translucent, as an illuminated stream of water. An outer surface of the body may be frosted or may include patterns that reflect or transmit the light. For example, the outer surface may include a plurality of ridges that spiral in helical fashion between the base and the aerator, the ridges transmitting relatively more light so that the helical pattern is accentuated. Alternatively, the outer surface can be encased in metal, plastic or any other hygienically approved material so that the light exits the spout in a ring around the aerator, and also from the aerator for the situation in which the aerator is translucent.
The plumbing light fixtures discussed above can be controlled in various ways. LEDs use little power and can be left on all the time, with the light sources providing beauty and interest to a sink, shower or bathtub area at all times, and also providing a night light for the bathroom for safety and convenience. Alternatively, a faucet lamp can be connected to a switch that is controlled by a light sensor, so that the lamp turns on automatically at night when other bathroom lights are off. As another example, a manually operated switch can be provided, and the switch can be located near other light switches for the room containing the faucet. The plumbing light fixtures can be provided with new construction or remodeling, and can also retrofit existing basins, fixtures and/or faucetry.
The LEDs can emit specific colors or essentially white light. For example, lights for faucet handles can be red for the hot water handle and blue for the cold water handle. Alternatively, the lights can be selected to match or contrast other colors in a room. Translucent blocks through which the light passes are helpful in dispersing light from an individual LED to avoid glare. Such blocks can be transparent or frosted, and can be colored separately from the light sources. Refractive and diffractive effects can also be employed to split multicolored or white light into various colors. The LEDs can be waterproof, and are also disposed within a sealed compartment such as a faucet base or spout.
FIG. 13 shows a faucet spout 400 with a translucent shroud 410 disposed near a base 412 of the spout for illumination. The shroud 410 , which may sometimes be called a bell or escutcheon, may be made of crystal, glass, acrylic or other materials. The shroud 410 is located in the base region of the spout because it is closer to the base 412 than to a tip 404 of the spout. A light source such as a plurality of LEDs disposed on a ring 414 shines light on an inner surface of the shroud 410 , which transmits the light through its outer surface. Such a light emitting shroud may also or alternatively be located on faucet handle, not shown.
FIG. 14 shows a faucet spout 500 with an opaque shroud 510 disposed near a base 512 of the spout. The shroud 510 has a skirt 515 that transmits light downward onto the base 515 to illuminate the base.
Although the present disclosure has focused on teaching the preferred embodiments, other embodiments and modifications of this invention may be apparent to persons of ordinary skill in the art in view of these teachings. For example, although LEDs are used in a preferred embodiment other light sources can alternatively be employed, such as fluorescent, incandescent, fiber optic, etc. Also, instead of or in addition to plumbing fixtures, light sources such as those discussed above can be included in trim for related accessories such as towel bars, towel rings, robe hooks, tissue holders, soap holders, etc. Therefore, this invention is to be limited only by the following claims, which include all such embodiments and modifications when viewed in conjunction with the above specification and accompanying drawings. | A plumbing fixture mounted to a sink or other basin has a base region that also serves as a source of visible light, providing a pleasing aesthetic effect. Separate bases for faucet handles and a faucet spout can be illuminated individually or as a group. A faucet spout, trim and/or handle can be made of translucent or transparent material (e.g., acrylic, plastic, glass, crystal, etc.) that captures and redirects light from the base, and may have opaque areas that provide other interesting patterns. The faucet light or lights can also serve as a nightlight for a bathroom or kitchen, saving the space that a separate nightlight would require. In another embodiment a light is provided in a faucet spout, which can illuminate a sink for a pleasing effect, and can also serve as a nightlight. The spout can be translucent, carrying light as well as water from its base. | 5 |
FIELD OF DISCLOSURE AND PRIORITY CLAIM
The present disclosure of invention relates generally to treatment of wounds to the integumentary system of a living creature and more specifically to ongoing treatment of wounds to the skin system of a human being or a like skinned other mammal. The disclosure relates yet more specifically to methods of adaptively controlling the environment of a wound as conditions in and around the wound site change, where the adaptive control is for promoting optimal healing of the wound even as conditions in the wound site change.
This application claims priority from U.S. Provisional Application No. 61/463,732, filed Feb. 22, 2011 by Oleg Siniaguine and Elena Kachiguina, entitled WOUND DRESSING FOR MOIST WOUND HEALING, the entire contents of which application are hereby incorporated by reference.
2a. Cross Reference to Co-Owned Applications
The following U.S. provisional patent application is owned by the owner of the present application, and its disclosure is incorporated herein by reference:
(A) U.S. Provisional Application No. 61/463,732, filed Feb. 22, 2011.
2b. Cross Reference to Issued Patents and Early Published Applications
The disclosures of the following U.S. patents and early publications are incorporated herein by reference:
(A) U.S. Pat. No. 7,910,789, issued Mar. 22, 2011 to Sinyagin; Dmitriy et al. and entitled “Method for treating wound, dressing for use therewith and apparatus and system for fabricating dressing”; (B) U.S. Pub. No. 20110162193 published Jul. 7, 2011 for Sinyagin; Dmitriy and entitled “Method for Treating Wound, Dressing for Use Therewith and Apparatus and System for Fabricating Dressing”; and (C) U.S. Pub. No. 20100241447 published Sep. 23, 2010 for Siniaguine; Oleg; et al. and entitled “Customization of Wound Dressing Using Rule-Based Algorithm”.
3. Description of Related Technology
The present disclosure of invention relates to treatment of wounds to the integumentary system of a living creature and more specifically to wound dressings of the type which can adaptively control the environment or micro-environments within and around a wound site by for example preventing certain parts of a healing wound site from prematurely drying out or getting excessively wet as treatment progresses, while also preventing certain other parts from becoming too dry, whereby such adaptive control of the wound site environment(s) tends to facilitate moist wound healing.
When a wound to the integumentary system of a living mammal (e.g., human being) occurs, the body tends to react differently over time by first, for example, producing relatively large amounts of liquids in and/or around the wound site, where the produced liquids tend to accumulate in the wound and which accumulated liquids are commonly referred to as “wound exudates”. Wound exudates may comprise a mixture of different substances including for example, blood, water, salts, proteins, and bacteria. Various studies of the wound healing process have demonstrated that, if kept appropriately physiologically moist in appropriate subregions thereof, a wound tends to heal substantially faster than if it is allowed to become too dry or too wet, especially in the final stages of healing. Such a form of controlled-moisture healing is referred to herein as “controlled moist wound healing”.
Tradition al wound dressings such as cotton gauze pads and the like operate to deter the escape from the wound site of moisture (water) in a liquid form, but the moisture tends to nonetheless escape in a vapor form (to evaporate into the ambient air) at an uncontrolled and often too rapid rate, which then causes the wound to dry out too rapidly, thus preventing optimal moist wound healing to occur when treated with a conventional cotton gauze pad or the like. Therefore, more advanced wound dressings have been proposed in the art for better controlling the escape rate of vapors from the wound site as well as the escape rate of liquids. However, dressings that are fixed in their design to minimize vapor escape are generally not well suited for appropriately treating wounds with medium to high exudate production rates, where for the latter types of wounds, a faster removal rate of exudate-sourced liquids and/or vapors may be more desirable. At the same time, such fixed design dressings are generally not well suited for appropriately managing the healthy and/or semi-healthy skin that surrounds the open wound site (the peri-wound skin) because exposure to excessive moisture can damage the peri-wound skin and thereby inhibit rather than promote wound healing.
Heretofore, wound treatment specialists have tried to implement controlled moist wound healing protocols by storing on hand, a relatively large inventory of different dressings with respective different sizes and respective different degrees of moisture absorbency, moisture storage capacity and/or vapor permeability. Under this paradigm, the health care providing specialists (specialists in wound care technology) are expected to be frequently checking up on the wound and its healing stage and frequently replacing old dressings with newer and more wound-appropriate newer dressings that address the ever evolving state of the healing (or not-healing) wound. In other words, the wound treatment specialists would attempt on a repeated basis to categorize each individually encountered wound at the time of encounter (e.g., when following up on wound healing progress and changing dressings) and to pick out from their then on-hand inventory of many different kinds of dressings, the dressing that best suites the then identified wound category. There are several drawbacks to this approach. First, the health care providing person who applies the first and subsequent wound dressings needs to be a well trained specialist in wound assessment and treatment. This can be costly. Second, the dressings may need to be changed frequently, which can significantly add to the cost of wound treatment. Additionally, because the human factor is involved, errors may occur in picking out the correct dressing kind each time the dressing is changed. Finally, a large inventory of different kinds of dressings has to be maintained and, if a needed type of fixed-design dressing is depleted from the on-hand inventory, the patient who then needs application of such a specific and fixed design dressing is out of luck.
In general and heretofore, wound treatment dressings were of fixed design relative to spatial and chronological evolution of the individual wound under treatment. Wounds change over time even during one dressing wear. The faster the wound heals, the faster the conditions within the wound site (e.g., exudate production levels, shapes and sizes of various tissue type micro-zones within the wound site, etc.) change under the same dressing. Typically, a wound includes at least three distinct spatial zones or areas whose shapes and sizes tend to change over time. These three major zones are sometimes referred to as the wound bed or wound core, the wound edge and the peri-wound skin which surrounds the wound edge. Healthy skin surrounds the wound edge, and although technically not part of the wound itself, the healthy skin can convert into being part of the wound if the healthy skin is maltreated during treatment of the wound site and its surrounds. The wound bed portion of the wound site is frequently subdivided and categorized into micro-zones or sub-zones, including a heavily exuding sub-zone which exhibits a relatively high intensity of exudate production, a granulating sub-zone horizontal a substantially lower or minimal rate of exudate production, and an epithelializing sub-zone having no appreciable amounts of exudates being produced thereat. Ideally, every such differently categorized tissue sub-zone should be treated with a specifically matched set of treatment parameters (including moisture level parameters). Consequently, for each differently categorized tissue sub-zone, there should be a corresponding wound dressing part that provides the desired treatment parameters for thereby implementing an optimal local micro-environment for the respective tissue sub-zone. More specifically, each heavily exudating part of the wound site should be overlapped by a wound dressing region which provides relatively high levels of liquid absorption and relatively high rates of vapor release (evaporation) into the ambient air. The high rate of vapor release is desired in order to avoid accumulation of excessive amounts of liquid in the heavily exuding part of the wound, where such accumulation tends to be detrimental to optimal healing. On the other hand, each low or non-exuding wound part needs to be kept moist but never (or hardly ever) too wet. Excessive drying out (undue desiccation) should be avoided, for example by designing the corresponding wound dressing region to prevent or minimize water vapor loss in the slow and/or not-exuding zones. These exemplary design requirements demonstrate how the needs of one sub-zone of a wound site can contradict those of another and yet the different sub-zones and their opposed needs typically coexist simultaneously in and around a single wound site.
As time goes by and the wound progressively heals (or as it progressively gets worse if for example appropriate antibiotics have not been applied or if it is unexpectedly re-injured) the zonal geographies and/or rates of exudate production and/or degrees of epithelialization of the wound site can dynamically change and, ideally, the dressing should be reconfigured to address these changes in timely fashion. However, heretofore, the state of the art in wound dressings did not provide an economical and practical means for addressing the divergent zonal treatment requirements typically found in and around a typical wound and it did not provide an economical and practical means for addressing the over-time, and sometimes rapid state changes that may occur in different sub-zones of the wound site. One example of an unexpected rapid state change in a wound is if the patient accidently bumps the wound site (with old dressing on it) into a sharp object and thereby re-injures the wound site.
The unexpected extreme injury to the wound site is but one example of how a dressing with fixed design may cease to provide appropriate healing-promoting micro-environments for respective micro-zones of an unexpectedly variable wound site. When a clinician inspects an encountered wound site for the purpose of formulating a treatment-appropriate dressing design for the wound, the clinician is merely seeing an out-of-the-field snapshot of the wound and of the patient to whom the wound belongs. At the time of clinical observation, the patient may be unusually anxious and this anxiety may lead to the wound exhibiting more than normal levels of exudate production. Once the patient leaves the clinic, he or she may calm down and the level of exudate production may then decrease as a result. However, what that generally means is that the clinician was induced by the distorted snapshot and in-clinic observation of the wound to provide a wound dressing that provides too fast of a drying action for the wound once the latter gets back into the field and the wound therefore heals at less than optimum rate or not at all because micro-zones therein are too dry.
On the other hand, it equally possible that the patient is less anxious or less agitated while in the clinic and wound exudates less than usual during the clinical preparation of the dressing. Once the patient gets out into his or her more normal world (the out-of-clinic normal routines), the patient may become more anxious or agitated due to work stresses for example or exercise routines and then the wound begins to exude at faster rates than were observed in the clinic. What this generally means is that the clinician was induced by the distorted snapshot and in-clinic observation of the wound to provide a wound dressing that provides too slow of a drying action for the wound once the latter gets back into the field. Therefore, once again, the dressing design that was fixedly set in the clinical environment provides a non-optimal treatment for the in-field wound. Other examples where the states of various micro-zones within the wound site may change can include ones where the patient consumes alcohol and/or various prescription drugs or other substances after leaving the clinic and these consumptions alter the state of the wound. Another example of where exudation rates can change is if the patient's blood pressure substantially rises for any of a number of reasons or instead falls below the levels present during the clinical visit. Yet another example of where exudation rates can change is if the patient's wound unknowingly got infected while at the clinic and the consequence of the infection does become apparent until long after the patient has left the clinic. At that point, because no one sees what is going on under the dressing, the changed conditions of the wound go undetected and untreated.
Given the above, it appears that wound treatment could be made much more economical and practical if a self-adaptive wound dressing could be developed which, not only at the time of initial application, appropriately and respectively absorbs exudates or hydrates at respective different rates at respective wound sub-zones (micro-zones) that need the respective rates of liquid absorption and vapor release into the ambient, but also that later on, automatically and adaptively self-adjusts to match changing wound conditions at respective sub-zones of the wound site and/or self-adjusts to match changing dimensions of such sub-zones while providing appropriate micro-environments for optimal promotion of healing for the respective sub-zones having the various wound tissue types, including for the wound edge subregions, and the peri-wound skin sub-zones. Additionally, wound treatment could be made much more economical and practical if the dressing is designed to assure that healthy skin surrounding the wound site is not damaged by the dressing. One advantage of an automatically self-adjusting adaptive wound dressing is that the persons applying the dressing to the wound (e.g., health care practitioners) would not have to be sophisticated experts in the art of selecting appropriate wound dressing materials (having appropriate treatment characteristics) and appropriately shaping and dimensioning them, and appropriately aligning them to respective portions of the wound site. Instead, they would simply apply the blank-slate wise, initially pre-configured dressing to the wound site without worrying about specific alignment and then the self-adaptive dressing would automatically and in concert with the encountered wound site conditions, automatically configure itself by appropriately altering material characteristics within the dressing to match the therapeutic needs of the then encountered underlying micro-zones within the wound site in such a way that the re-configured material zones automatically align with the underlying micro-zones. Moreover, because the self-adjusting adaptive wound dressing continues to re-adjust itself to ever changing conditions within the wound site, the person(s) who apply the dressing would not have to change dressings as often; and also they would not have to keep as large an inventory of different dressings as they now have to keep on hand because an automatically self-adjusting adaptive wound dressing would custom-tailor itself to the unique needs of each encountered and unique wound (and its unique interior subregions) without calling for subjective human judgment. The self-adjusting adaptive wound dressing would automatically follow along with and self-adapt to the unpredictable changes in the wound site during the duration of application of the dressing. As mentioned above, one example of an unpredictable change in the wound site during the duration of a dressing wear is if the patient accidently bumps the wound site (with old dressing on it) into a sharp object and thereby re-injures the wound site whereby one or more wound site subregions that were previously non-exuding ones suddenly become heavily exuding ones due to the new injury inflicted on the otherwise healing wound site. A conventional dressing that is not self-adaptive could not automatically and relatively immediately respond to such suddenly changed conditions.
It is to be understood that this background of the related technology section is intended to provide useful background for understanding the here disclosed technology and as such, the technology background section may and probably does include ideas, concepts or recognitions that were not part of what was known or appreciated by those skilled in the pertinent art prior to corresponding invention dates of subject matter disclosed herein.
SUMMARY
In accordance with one aspect of the present disclosure of invention, an automatically self-adjusting variable permeability providing (AVPP) layer is provided over and in operative interactive coupling relation with a wound site containing a wound to the integumentary system of a living creature such as the skin of a human patient. The AVPP layer has the capability of automatically changing in respective fluid permeability characteristics provided by respective subregions of the AVPP layer where the changes are in reaction to extant or changed conditions in corresponding micro-zones of the wound site. The automatic self-adjusting behaviors of the respective subregions of the AVPP layer can include providing a faster rate of vapor removal for micro-zones of the wound site that are too wet and providing a slower rate of vapor removal or essentially no vapor removal for micro-zones of the wound site that are too dry. The automatically self-adjusting variable permeability providing (AVPP) layer may form part of a wound treatment dressing applied to an underlying wound site. The dressing may additionally include a liquid-impermeable but vapor breathing (LIVB) layer disposed above the AVPP layer and a liquid absorbing layer or pad disposed under the AVPP layer. In operation, the liquid absorbing layer transmits to respective subregions of the AVPP layer, fluids that, if present, are indicative of tissue states of the micro-zones of the underlying wound site and the AVPP layer automatically and self-adjusting wise provides corresponding fluid permeability characteristics for appropriately keeping the respective micro-zones as not too wet and not to dry for sake of promoting healing of the wound.
BRIEF DESCRIPTION OF THE DRAWINGS
The below detailed description section makes reference to the accompanying drawings, in which:
FIG. 1 is a schematic cross sectional view of an automatically adaptive (and optionally manually further adaptable) wound dressing according to one aspect of the present disclosure of invention;
FIG. 2 is a schematic cross sectional view of another embodiment having first and second vapor permeable layers where at least one of the vapor permeable layers exhibits an adaptively programmable MVTR profile;
FIG. 3 is a schematic cross sectional view of another embodiment having a first vapor permeable layer spaced inwardly from the outer perimeter of a second and overlying vapor permeable layer;
FIG. 4 is a schematic cross sectional view of another embodiment having a second vapor permeable layer attached to the absorbing core;
FIG. 5 is a schematic cross sectional view of another embodiment having a spacer disposed between the first and second vapor permeable layers;
FIG. 6 is a schematic cross sectional view of another embodiment having a third vapor permeable layer;
FIG. 7 is a schematic cross sectional view of a further embodiment having a second absorbing layer disposed above the automatically-variable permeability providing (AVPP) layer; and
FIG. 8 is a schematic cross sectional view of yet a further embodiment having a fluids lateralizing layer disposed above the second absorbing layer.
DETAILED DESCRIPTION
With regard to the figures, it is to be appreciated that these are not to scale and the illustrated thicknesses are generally exaggerated relative to the illustrated lateral widths of the dressings. The terms, upper and lower will be used herein as relative terms that are applicable to the case where the dressing is positioned as shown in the drawings with one layer being disposed above a next and so forth. Flipping the dressing upside down or otherwise (e.g., at other angles) does not alter the relative, upper versus lower; or above versus below designation given herein to the various layers. Similarly when various fluids are stated herein to be drawn “up” for example or spread out “laterally” (horizontally) for example, those designations are also to be understood as relative terms. Flipping the dressing upside down or otherwise (e.g., at other angles) does not alter the relative, up versus down; or lateral versus vertical designations given herein to the various fluid flow directions.
Referring to FIG. 1 , a first example of an automatically adaptive wound dressing 1 in accordance with the present disclosure is depicted therein by an exemplary cross sectional view. The from-the-above top plan view (not shown) may take on many different shapes, dimensions or configurations that generally comport with the illustrated and exemplary cross sectional view of FIG. 1 , where the latter cross sectional view may be taken along a desired sectioning line or sectioning curve drawn on the top plan view (not shown). More specifically, in FIG. 1 the dressing 1 is shown to comprise a liquid(s) adsorbing pad 2 , a first vapor permeable layer 3 and a second vapor permeable layer 4 stacked over one another in the recited order. Of importance, in the various embodiments the first and second vapor permeable layers 3 and 4 are not of identical function. The first vapor permeable layer 3 may be made permeable to liquids (e.g., liquid water) as well as being permeable to vapors (e.g., water vapor) while the second vapor permeable layer 4 is not permeable to liquids. Both of the first and second vapor permeable layers, 3 and 4 may be made impermeable to molecules and/or to particles substantially larger than H2O molecules, for example to bacterial cells or cell fragments. Although the first and second layers, 3 and 4 , are frequently referred to herein as vapor permeable layers, from time to time the second layer 4 will also be referred to as a “liquid-impermeable but vapor breathing” (LIVB) layer 4 . On the other hand, the first mentioned layer 3 will also be referred to herein as an “automatically-variable permeability providing” (AVPP) layer 3 for reasons that will shortly become apparent.
The absorbent pad 2 is permanently (nondetachably) attached to at least one of the first and second vapor permeable layers, 3 and 4 , and in the illustrated case of FIG. 1 it ( 2 ) is shown to be so attached to a lower first side 5 of the first vapor permeable layer 3 . The second vapor permeable layer 4 (a.k.a. the liquid-impermeable but vapor breathing (LIVB) layer 4 ) is bonded to an upper second side 6 of the first vapor permeable layer 3 . In one embodiment, parts (e.g., removable strips or dots) of the upper or second vapor-permeable/liquid-impermeable layer 4 (LIVB) are detachably bonded to the underlying layers or films and may be manually and/or by machine-means, selectively removed (e.g., by scratch or peel-off removal) so as to thereby alter local fluid (vapor) exhaust rates there-at.
In the same or another embodiment, parts (e.g., micro-zones) of the first vapor permeable layer 3 (a.k.a. the automatically-variable permeability providing (AVPP) layer 3 ) are time-release wise and/or concentration of exposure-wise changed by having been exposed to a change-triggering concentration or amount of moisture (e.g., a vapor and/or liquid that triggers chemical change in AVPP layer 3 ) whereby, at first; before they are exposed to a sufficient amount of moisture, the respective micro-zones will exhibit a comparatively low rate of vapor transmission (a low MVTR, as shall be defined below) but after having been exposed over time to a sufficient amount of moisture (e.g., a sufficient concentration of a particular type of liquid for a sufficient length of time), they will exhibit a comparatively higher rate of vapor transmission (higher MVTR) so to thereby automatically increase a moisture-removal rate provided for the wound site tissue below them. And then later, after local moisture concentration drops below a predetermined level, the variable parts (micro-zones) of the first vapor permeable layer 3 (the AVPP layer) will revert to exhibiting a comparatively lower rate of vapor transmission (lower MVTR) so to thereby automatically prevent excessive drying out of the wound site sub-zones below them after a desired amount of local moisture-removal has occurred. This low, high, and then low-again vapor transmission rate behavior is particularly useful for proper treatment of the peri-wound skin and epithelializing parts of the wound site. The latter two parts should be progressively growing inward towards the center of the wound site while the respective moisture levels in those respective sub-zones are kept optimal for those zones to keep growing inwardly and thus continue the healing process. More specifically, the outer periphery of the peri-wound skin zone generally calls for a drier but not arid micro-environment while the zones inward of the peri-wound skin zone typically call for a wetter micro-environment. During healing, the boundary between the two zones advances (travels) inwardly as the wound heals and thus the optimal but different micro-climates for the two zones should spatially advance inwardly with their respective wound site zones.
The liquid absorbing pad 2 operates to draw excessive exudate away from the wound site and to store components (e.g., drawn up bacterial cells) of the removed exudate apart from the underlying wound site. The liquid absorbing pad 2 may include one or more of hydrophilic fibrous or foam materials which can readily absorb (bind to them) substantial quantities of water or aqueous solutions and store drying out components of the absorbed and drawn up liquids. The pad 2 preferably comprises a non-woven fabric such as an air-layered or meltspun or electrospun rayon or polyester, or polyvinyl alcohol (PVA) and/or its ethylene copolymers, or other hydrophilic synthetic or natural polymers and materials useful for adsorption and absorption of substantial quantities of water or aqueous solutions. The absorbent pad 2 may contain embedded gelling fibers or particles (globules) of super-absorbent polymers (e.g., polyacrylamide or polyacrylate such as those marketed by Emerging Technologies, Inc., Greensboro, N.C.) or other known hydropolymers that bind water (e.g., alginates, reprocessed cellulose, crosslinked or high molecular weight polyethylene oxide, polyvinylpyrrolidone). The absorbency of the pad material is preferably at or higher than 10 grams-of-absorbed liquid per gram of absorbent (≧10 g(L)/g(A)) for, for example, a 0.9% sodium chloride and calcium chloride solution that is considered to be close to the composition of typical wound exudate. Absorption Capacity may be measured according to the DIN EN 13726-1 standard. In one embodiment, the absorbency of the pad material progressively increases as one moves upwardly (e.g., in the +Z direction) in the cross-sectional view of FIG. 1 whereby the effect is that initially encountered exudates are rapidly drawn up and away from the wound site for storage in, and for drying out within the upper parts of the liquid absorbing pad 2 while later encountered exudates (e.g., those with fewer amounts of bacteria and/or dirt) are more slowly drawn up into the lower sections of the pad 2 . One of the reasons that slower absorption rates may be desirable after initial absorption of exudates is so that the micro-environment of the underlying wound zone does not become too dry after the initially large amount of exudate has been taken up. In one embodiment, the absorbent pad 2 exhibits a directional absorption preference that favors drawing liquids more so in the upward direction (e.g., in FIG. 1 ) rather than laterally so that liquids drawn up from a first sub-zone of the wound site tend to not flow laterally through the absorbent pad 2 and thereby appear to higher layers (e.g., 3 and 4 ) of the dressing as if the liquids had instead been drawn up from a laterally spaced apart, other sub-zone of the wound site.
The absorbent pad 2 material may include antimicrobial additives, like broadly used silver and silver salts, polyaminopropyl biguanide (PAPB), polyhexamethylene biguanide (PHMB), polyhexamethylene guanide or polyhexanide, or other known in the art antimicrobials, antiseptics and/or preservatives in known and recommended for use concentrations that are non-cytotoxic, typically 0.01-0.5% by weight.
The absorbent pad 2 may include embedded hygroscopic liquids for providing a desired degree of fiber and/or particle softening so that the dressing can easily flex when applied to the wound site. Preferably, the embedded hygroscopic liquid is polypropylene glycol or glycerin. The amount of hygroscopic liquid is preferably 0.001-0.05 g/cm 2 , and more preferably 0.005-0.03 g/cm 2 .
The absorbent pad 2 may initially be pre-charged with an embedded quantity of sterile water (or saline solution) for irrigating and moisturizing the wound site at an initial stage of wound treatment. The amount of water in the absorbent pad 2 may be about 50-80 weight %. Preservatives like benzyl alcohol 0.9% or 0.085% chlorhexidine gluconate or 0.02% bronopol may be added to the water pre-charge. In one embodiment, the pre-charged irrigation liquid(s) is/are stored in pressure frangible beads which break open when sufficient pressure is applied to them. More specifically, the user may be instructed to knead the packaging that holds the dressing before taking out the dressing and applying it to the wound site. (See for example US Pub 2007/0020320 “Wound dressing and methods of making and using the same”, David et al which is incorporate herein by reference.)
The absorbent pad 2 may initially be pre-charged with an embedded mixture of water and hygroscopic liquid. The percent of hygroscopic liquid in the water-glycerin mixture may be about 5-75% w (by weight), and more preferably 10-30% w. The amount of water-hygroscopic liquid mixture initially provided within the absorbent pad 2 may depend on the percentage of hygroscopic liquid in the mixture, and may be such that the resulting amount of water in the absorbent pad 2 is 10-80 weight %. The resulting amount of water or aqueous solution initially provided within the absorbent pad 2 may be less than the maximum absorption capacity of the absorbent pad 2 . One function of such an initially provided pre-charge of water or aqueous solution may be to irrigate the wound site with sterile liquid prior to or at the same time as beginning to absorb exudate. As indicated above, the initial irrigating liquid(s) may be stored in frangible beads or the equivalent embedded within the absorbent pad 2 and released when the pad is kneaded by hand or by appropriate machine means.
The absorbent pad's vertical thickness and lateral length and width dimensions may vary depending upon the intended use for the dressing. The thickness of the absorbent pad 2 may be between 1 and 3 mm or thicker, preferably 1.5-2 mm. The dressing is typically made in a range of sizes: 5×5 cm, 10×10 cm, 15×15 cm, 20×20 cm as measured in the lateral directions. Therefore the lateral dimensions are substantially larger than the vertical thickness. The shape of the absorbent pad (as seen in the top plan view) may be rectangular or oval or another shape specifically applicable to a particular part of a human body where the dressing is to be applied to. In use, the lower major surface of the absorbent pad 2 engages directly or indirectly with the wound site while the second vapor permeable layer 4 (the liquid-impermeable but vapor breathing (LIVB) layer) interfaces with the exterior air. The serial combination of the first and second vapor permeable layers, 3 and 4 , controls the rate of vapor exhaust from the interior of the dressing and into the ambient air. The upper vapor permeable layer 4 may optionally have parts that can be selectively detachably removed from the lower vapor permeable layer 3 (or from lower film layers of the second vapor permeable layer 4 itself) in the form of rectangular strips or circular ones of concentric rings or otherwise so that, for example, quick detach removal or scratching away of more central and upper film parts of the upper vapor permeable layer 4 (e.g., those at or closer to the central surface area of the dressing) will result in a dressing that has higher rates of vapor exhaust nearer to the central and more heavily exudating core of the wound site while initial non-removal of the more peripheral strips or rings of the upper vapor permeable layer 4 result in a dressing that has lower rates of vapor exhaust at or near the peripheral areas of the wound site (e.g., above the peri-wound skin and surrounding healthy skin). As time progresses, the outer removal rings (of layer 4 ) may be progressively removed to promote further drying around the outer periphery of the peri-wound area as the latter advances (grows) inwardly during the course of typical wound healing. In one embodiment, a scratch-resistant, but fluid passing mesh (not shown) is interposed between a top and optionally detachable film of the vapor-permeable/liquid-impermeable layer 4 and a lower but not detachable film of the same layer 4 (films not separately shown). The optional, scratch-resistant mesh (not shown) protects the lower film from being removed even as the upper one is scratched or peeled away. In this way, the general liquid-impermeable but vapor breathing (LIVB) properties of the second vapor permeable layer 4 are substantially preserved.
In another embodiment ( FIG. 2 ), the wound-facing bottom side 60 of the absorbent pad 2 is covered with a wound-contacting layer 61 , where the wound-contacting layer 61 rather than the absorbent pad 2 defines a directly wound-contacting face of the dressing. The wound-contacting layer 61 is permanently (e.g., nondetachably) attached to the absorbent pad 2 . The wound-contacting layer 61 may be made of a pre-sterilized liquid permeable mesh or perforated film or liquid permeable non-woven fabric. The wound-contacting layer 61 should be made of a material that is biocompatible with the wound site and may be made of a synthetic or biologic or bioabsorbable polymer or their combinations. Examples of such polymers include nylon, polyethylene, polyvinyl alcohol (PVA), ethylene vinyl acetate and/or ethylene vinyl alcohol copolymers, which are typically non-adherent to the wound tissue. The wound-contacting layer 61 should be perforated or porous to allow for the passage therethrough of wound moisturizing liquid and/or exudate liquid and/or wound moisturizing vapor. The thickness of the wound contact layer 61 may be in the range of about 5-500 microns and the pore size may be in the range of 0.1-1000 micron. The wound contact layer 61 material may include antimicrobial additives, like broadly used silver and silver salts, polyaminopropyl biguanide (PAPB), polyhexamethylene biguanide (PHMB), polyhexamethylene guanide or polyhexanide, or other known in the art in concentrations that are non-cytotoxic, typically 0.01-0.5% w.
In one embodiment, the whole of the automatically-variable permeability providing (AVPP) layer 3 is at least partially or completely soluble in water and/or in specific other liquids such that if respective sub-portions of layer 3 are exposed to wet exudate for example, the respective sub-portions will partially (e.g., proportionally) or fully dissolve into the surrounding liquid and thereby automatically create corresponding areas of increased vapor permeability (faster vapor escape rates) in the dressing. In an alternate embodiment, first vapor permeable layer 3 (e.g., that of FIGS. 1 and 2 ) instead includes spatially distributed material spots 10 that are at least partially or completely soluble in water and/or in specific aqueous liquids such that if they are exposed to wet exudate for example, they will partially (e.g., proportionally) or fully dissolve into the surrounding liquid and thereby automatically create corresponding areas of increased vapor permeability (faster vapor escape rates) in the dressing. Other portions ( 11 ) of the automatically-variable permeability providing (AVPP) layer 3 are not dissolvable or substantially less easily dissolvable. The dissolving of the spots 10 and/or respective sub-portions of the automatically-variable permeability layer 3 need not create a through hole at the spot (e.g., 10 ) where the dissolving occurs but rather such dissolving may instead create a region of reduced film thickness. Such reduced film thickness correlates with a higher MVTR. Additionally, the dissolving of the spots 10 and/or respective sub-portions of layer 3 to the point where through holes are created may cause the lower or first vapor permeable layer 3 to become permeable to liquids as well as to water vapor. This occurs if the amount of dissolution at spots 10 (or other dissolvable sub-portions of layer 3 ) is large enough to create through holes. In other words, liquid permeability is induced when the local concentration of a hydrolyzing liquid (e.g., exudate) is sufficiently high and is present for a sufficiently long time (and optionally also has a required level of acidity or other chemical attribute) to completely eat through a significant portion of hydrolyzable polymer bonds present at that spot 10 (or other alike sub-portion). Examples of materials which can be tailored to have such characteristics include polyvinyl alcohol (PVA), poly ethylene oxide, poly vinyl pyrrolidone and other known polymers and/or their blends or co-polymers with various degrees or cross-linkage breakability or hydrolyzation-ability being integrated into the characteristics of the picked polymer. As used herein, the “degree” of cross-linkage breakability or hydrolyzation-ability measures the proportion of locally present polymer bonds that can be broken by a corresponding hydrolyzation process. (As understood in the chemical arts, hydrolyzation is a chemical process resulting in bond decomposition, where the process involves the splitting of the bond and the addition to, or substitution at the location of the broken bond of a hydrogen cation and a hydroxide anion in place of the bond; where the H + and OH − substitutes may be obtained from surrounding water molecules for example.)
The first vapor permeable layer 3 may be made in the form of a non-porous film (a solid film through which gases may diffuse but liquids cannot flow) having alternating spots 10 of hydrolysable (soluble) material and surrounding mesh areas 11 of non-hydrolyzable (non-soluble) material each with a thickness of about 25-300 microns. In embodiments where upper film strips of upper layer 4 are additionally, optionally detachable, the detachable upper portions preferably overlap only the non-dissolvable mesh portions 11 of the lower, first vapor permeable layer 3 so that open holes (for bacteria to get in) will not be created by combined complete dissolution of the hydrolyzable material spots 10 of the first vapor permeable layer 3 and optional detachment of the detachable portions of the upper, second vapor permeable layer 4 .
The first vapor permeable layer 3 (the automatically-variable permeability providing (AVPP) layer 3 ) may be made of the above-mentioned materials which initially have relatively low Moisture Vapor Transmission Rates (MVTR) such as <1000 g/m2/24 Hour, preferably <500 g/m2/24 H, when the material is dry (it has not yet been exposed to a hydrolyzing liquid), and it has a substantially increased MVTR, for example >1000 g/m2/24 Hour when the material has been exposed to a hydrolyzing solution (e.g., exudate) for a sufficiently long time duration. Therefore subregions of the dressing that are exposed at layer 3 to exudate absorbed thereto from a corresponding subregion of the wound site and for long enough of an exposure period will adaptively and automatically convert to dressing subregions of relatively higher vapor transmission (e.g., MVTR>1000 g/m2/24 Hour) while subregions of the dressing that are not exposed at layer 3 to large concentrations of exudate absorbed thereto from a corresponding subregion of the wound site and/or for not long enough of an exposure time will remain substantially in their initial and relatively low MVTR state (e.g., MVTR<500 g/m2/24 H). In other words, the dressing automatically and adaptively self-adjusts according to the degree of exudate absorbed from each respective micro-zone of the wound site and transmitted to a corresponding hydrolyzable material spot (e.g., spot 10 ) of the first vapor permeable layer 3 . In one embodiment, the lower, first vapor permeable layer 3 also automatically becomes increasingly more permeable to small-sized liquid molecules (e.g., H2O) when exposed over time to sufficient concentrations of a hydrolyzing solution (e.g., exudate). The advantage of this aspect will be discussed when the spacer-including embodiments of FIGS. 5 and 6 are discussed later below.
MVTR (Moisture Vapor Transmission Rate) may be measured according to the DIN EN 13726-2 standard. (DIN is a German abbreviation which in English means the German Institute for Standardization.)
In one embodiment, the dissolvable spots 10 of the first vapor permeable layer 3 include temperature-dependent spots 10 which are made of one or more materials that are soluble only in above-room-temperature water or aqueous solution with a temperature for example that is >25° C. More specifically, the hydrolyzing solution (e.g., exudate) may be heated to above normal room-temperature by the patient's body heat (and/or by another heat providing means—e.g., an electric heating element). An example of such a temperature-sensitive material may be polyvinyl alcohol (PVA) with 60-80% degree of hydrolyzation, where here, the percent of hydrolyzation indicates what proportion of available polymer bonds are broken by prolonged exposure at temperature to the hydrolyzing solution.
The upper or second vapor permeable layer 4 may be made of a nonporous film or non-woven fabric with a relatively low moisture vapor transmission rate (MVTR) or it may be made of multilayer combinations of non-woven fabric and nonporous film materials permanently and/or detachably bonded together to provide a desired MVTR for that second vapor-permeable/liquid-impermeable layer 4 . The thickness of the second vapor permeable layer 4 may be in the range of about 10-150 microns, or more preferably 50-100 microns. The material of the second vapor permeable layer 4 may include polyethylene, polypropylene, polyester and/or poly vinyl acetate.
Of importance, the upper or second vapor permeable layer 4 should be made of a liquid impermeable and microorganism impermeable material that nonetheless transmits vapor with an MVTR >1000 g/m2/24 H. By contrast, the lower or first vapor permeable layer 3 may be composed of one or more materials that, when converted by hydrolyzation; do permit small sized liquid molecules (e.g., H2O) to permeate through them but preferably still block larger sized particles (e.g., microorganisms) from permeating through.
Laminations of thin polyurethane films may be used to meet the above preferred characteristics for the second vapor permeable, but liquid impermeable layer 4 . The films of layer 4 may each have a thickness of about 10-50 microns and may provide MVTR's up to 3000 g/m 2 /24 hours depending on composition and thickness. Preferably, the film or films for second layer 4 is/are chosen to exhibit an MVTR greater than 2000 g/m 2 /24 hrs while still being impermeable to liquids. In one embodiment, if multiple films are used for forming the second vapor permeable layer 4 , they are provided with respective different colors, for example red and blue with the blue covering the red (and a scratch resistant mesh being optionally interposed between). A user may scratch off or otherwise selectively remove the upper and first colored film to thereby expose the lower and differently colored film of the liquid impermeable layer 4 (optionally through a see-through scratch resistant mesh). By this means, the user (e.g., health care provider) can readily see what pattern of selective increase of MVTR for water vapor is being provided by the manually programmed (or machine-wise automatically programmed) selective removal of part of the top of layer 4 . In one embodiment, an exposed red color is understood to mean a higher MVTR while blue indicates a lower rate.
Hydrophobic non-woven fabrics and micro-porous membranes (e.g., those marketed by the 3M™ Company) with pore sizes of 0.1 micron or less are also micro-organism impermeable and resistant to passing water and water based liquids but provide relatively high MVTR due to their open micro-pore structures. Polypropylene or other hydrophobic polymers may be the material of choice for non-woven layer or micro-porous membrane. Typical thickness of the non-woven film for layer 4 or a membrane thereof is 50-500 microns.
The second vapor permeable but liquid impermeable layer 4 may be made as a multi-layer stack of films and non-woven fabrics permanently or detachably bonded together (not shown in Figs). Such stacks may help minimize the inconvenience of thin film handling but still preserve the desired high MVTR rating for the second layer 4 .
The first vapor permeable layer 3 is preferably bonded to the absorbing pad 2 with a porous adhesive (not shown on the Figs.) where the porous adhesive has open cell pores after curing and thus allows for passage of liquid therethrough. The pore size of the cured adhesive may be 0.1-200 microns. The more preferred pore size is 0.1-10 microns. (An example of such an open pore adhesive is a porous adhesive marketed by Adhesive Research, Inc., Glen Rock, Pa.).
It will be appreciated that the vapor permeable layers 3 , 4 , the absorbent pad 2 and wound contact layer 61 could be manufactured and/or later cut to have any suitable shape and dimensions such as 3×5 inch rectangular, circular, oval, triangular or other specific to a particular part of a human or animal body and the shape and size of the wound site.
Other adaptive dressings in accordance with present disclosure of invention may comprise one or more additional vapor permeable layers placed on top of and/or below the second vapor permeable layer 4 . The additional layers may have the same or similar features as said second vapor permeable layer 4 , including optional, non-automatic (e.g., manual) programming of the MVTR in different areas of the dressing's upper surface.
The respective outer perimeters of the absorbent pad 2 and the first and second vapor permeable layers 3 and 4 may be laterally coextensive with one another, i.e., vertically superimposed (see FIGS. 1-2 ), so that the entire upper surface area of the absorbent pad 2 is covered in the lateral directions by the first and second vapor permeable layer 3 and 4 . In a variation, the peripheries of one or both of the first and second vapor permeable layers 3 and 4 may extend beyond the lateral periphery of the absorbent pad 2 so that sidewalls of the absorbent pad 2 are covered by at least one of layers 3 and 4 .
The permanent attachment of the absorbent pad 2 to the first vapor permeable layer 3 can be made by lamination, or by extruding the film material of layer 3 directly onto the absorbent pad 2 material, or by electrospinning of fibrous material of the absorbent pad 2 directly on the material of the first vapor permeable layer 3 . If lamination is employed, the lower, first side 5 of the first vapor permeable layer 3 may be coated with a pressure sensitive (pressure activated) adhesive (not shown in the Figs.). This attachment adhesive should have an MVTR that is not less than the MVTR of the first vapor permeable layer 3 . That may be achieved by using a patterned adhesive with >50% of the open area. (An example is a patterned pressure sensitive adhesive, marketed by SCAPA, Inc. of Inglewood, Calif.)
As mentioned above, some segments or spots 11 of the first vapor permeable layer 3 may be made non-soluble ( FIG. 2 ) to water or aqueous solutions. This may be achieved by patterned localized crosslinking of the polymers by known thermal, chemical, ultraviolet and/or irradiation methods. Localized crosslinking of a polymer film may be achieved by masking of the to-be-left-as soluble film areas 10 prior to and during chemical, thermal or irradiation exposure. The non-soluble areas 11 are distributed, preferably, uniformly laterally and as a structurally integrated mesh along at least the top surface area of the first vapor permeable layer 3 with area sizes 0.01-20 mm, and coverage of 10-90% of total combined area of the top surface area of the first vapor permeable layer 3 .
The first vapor permeable layer 3 may be made by coextrusion of a water soluble polymer as mentioned above and of a water resistant (nonsoluble) polymer (polypropylene, polyethylene, poly vinyl acetate, etc). In this case, the areas 11 of water resistant polymer are distributed, preferably, uniformly laterally along the first vapor permeable layer 3 with area sizes 0.01-20 mm, and 10-90% of total combined area.
In another embodiment, the periphery of the first vapor permeable layer 3 is spaced inwardly (as shown in FIG. 3 ) for 1-30 mm, preferably, 20 mm from the lateral outer perimeter of the second vapor permeable layer 4 . The second vapor permeable layer 4 is directly bonded to the absorbing pad 2 near the periphery of the absorbing pad 2 . In this case, since the periphery of the dressing is not covered by all of layers 3 and 4 , but rather by a fewer number (e.g., one) of vapor permeable layers, the periphery of the dressing exhibits a higher MVTR and thus allows the periphery of the wound site to be drier than the core.
In another embodiment, the first vapor permeable layer 3 is provided with through openings 7 ( FIG. 4 ). The openings 7 in layer 3 may have a lateral size (e.g., diameter of) 0.4-5 mm, and may be of various shapes, and may be uniformly distributed over the total lateral surface area consumed by the first vapor permeable layer 3 . The combined area of the through openings 7 should be less than 20%, and more preferably less that 5%, of the consumed surface area of first vapor permeable layer 3 . The second vapor permeable layer 4 is directly bonded to the absorbing pad 2 through the openings 7 . The bonding adhesive used in openings 7 may be a porous one or a non-porous one depending on whether the dressing is designed to intentionally let vapors escape through the bonding openings 7 (and then through vapor permeable layer 4 ) or not.
Referring to FIG. 5 , in another embodiment, an open cells, porous or perforated spacer layer 12 may be interposed between the first vapor permeable layer 3 and the second vapor permeable layer 4 . Preferably, the spacer layer thickness is about 10-250 microns, the pore size 13 is 1-100 microns with 5-90% of open void area. The open cell pores or openings 13 may provide lateral liquid communication between each other. The spacer layer 12 may be made for example of a porous adhesive marketed by Adhesive Research, Inc. of Glen Rock, Pa.). The spacer layer 12 may be made by dots of an adhesive material that bonds with the first vapor permeable layer 3 and bonds with the second vapor permeable layer 4 (an example is MacTac™ glue dots marketed by MacTac, Inc. of Stow, Ohio). Although not specifically shown, the automatically-variable permeability layer 3 includes hydrolyzable material whereby its permeability at local spots to vapors and/or liquids changes when exposed for sufficiently long time to a hydrolyzing liquid (e.g., exudates). When a large concentration of exudates is present at a given sub-zone for a long time, the hydrolyzable layer 3 automatically breaks down at that location and then the exudate escapes through the broken down area to spread laterally into the pores of the porous or perforated spacer layer 12 . This increases the lateral surface area by way of which vapors from the laterally spread liquid can permeate through vapor-permeable/liquid-impermeable layer 4 and out into the ambient. The rate of evaporation is thus automatically increased.
Referring to FIG. 6 , in another embodiment, the function of the first automatically-variable permeability providing (AVPP) layer 3 may be provided by two or more spaced apart layers such as 15 and 16 separated from each other by an open cells porous or perforated spacer layer such as 17 . Preferably, each layer 15 and 16 has a thickness of 10-250 microns, the pore size 20 is 1-100 microns with 5-90% of open void area. The respective MVTR variability characteristics of the spaced apart layers 15 and 16 need not be the same. The open cell pores or openings 20 of spacer layer 17 may provide lateral liquid communication between each other. The spacer layer 17 may be made of porous adhesive marketed by Adhesive Research, Inc., USA. The spacer layer 17 may be made by dots of an adhesive material that bonds well with each of layers 15 and 16 (an example is MacTac™ glue dots marketed by MacTac, Inc. USA). In the embodiment of FIG. 6 , the spacer layer 12 between automatically-variable permeability layer 16 and vapor-permeable/liquid-impermeable layer 4 is also present.
In one embodiment, prior to employment at a wound site, the dressing 1 is packaged in a moisture and micro-organism impermeable pouch, sealed and pre and/or post sterilized by any of known in the art methods like gas sterilization or gamma or electron beam irradiation. The dressing packaging may include indicia identifying the dimensions, shapes MVTR ranges and liquid storage capacities of the enclosed dressing.
To apply the dressing to a wound, the user (e.g., health care provider) opens the sterile pouch, orients it so that the wound contact layer 60 faces the wound, and positions the lower surface 61 of the wound contact layer against the wound so that the wound center approximately coincides with the dressing center. The upper surface of the dressing may include centering indicia such as crosshair lines that may be lined up with crosshair line extensions drawn on healthy areas of the patient's skin outside of the per-wound areas.
In the case of FIGS. 3-6 where the second vapor permeable layer 4 extends peripherally beyond the first vapor permeable layer 3 so that a higher MVTR is provided in the peripheral areas of the wound site, the moisture (e.g., water vapor) output from the peri-wound skin area is rapidly exhausted through the areas covered only by the first vapor permeable layer 3 so that the healthy skin area surrounding the wound site remains relatively dry. An occasional droplet of perspiration generated at the peri-wound skin or healthy skin area may be is absorbed by the co-extent absorbent pad 2 and thereafter evaporated through the immediately overlying second vapor permeable layer 4 of the peripheral zone. As a result, the mini-environment over the peri-wound and healthy skin areas remain appropriately dry without accumulation of skin-damaging liquid thereat. This helps prevent skin maceration.
If an encountered wound is identified as low exuding or has no exudates (low drainage), the limited moisture (exudate, secretion, water vapor) from the wound bed is absorbed by the absorbent pad 2 but moisture vapor evacuation (exhaust) from over the wound bed and out to the ambient air is constrained by the presence of the non-hydrolyzed first vapor permeable layer 3 which initially has a relatively low MVTR and stays in that state if not hydrolyzed by absorbed and upwardly drawn exudates. As a result, when the encountered wound zone conditions are that of there being no or relatively low levels of exudates, the initially low MVTR of the automatically-variable permeability layer 3 remains low, the micro-environment over the wound bed is therefore kept moist and of a relatively high-humidity where the latter prevents desiccation of the surface of the wound bed and this facilitates optimal conditions for inward cell growth proliferation (from the surrounding peri-wound areas) and thus rapid wound healing. The presence of the low MVTR, first vapor permeable layer 3 over the peri-wound areas also supports a relatively high or medium humidity environment over the wound edge and this helps to prevent wound edge desiccation and/or damage to newly epithelialized skin.
If, on the other hand, a given part of a wound site is highly exuding (high liquid production rates), the exudates are absorbed by the absorbent pad 2 over that part of the wound site and drawn up into contact with the automatically-variable permeability layer 3 . The vapor evacuation (exhaust to the outside) is initially slow in this region because of the vapor flow restricting, serial combination of the first and second moisture vapor permeable layers 3 and 4 , where the serial combination exhibits a low combined MVTR. As absorption begins, the water portion of the exudates mixture is initially bound to the superabsorbent or hydropolymer particles of fibers in the absorbing core of pad 2 so that initially there are no free flowing water particles in the pores between the superabsorbent particles and fibers.
If and when the amount of liquid absorbed by the pad 2 becomes sufficiently large after some time (e.g., after the dressing is worn by the patient for a predetermined number of hours), the absorbed liquid saturates the water binding capacity of the water-binding material and subsequently, free-flowing (unbound) water will appear in the spaces between the water-binding particles and/or fibers of the absorbent pad 2 . Eventually this unbound liquid rises to and reaches the first vapor permeable layer 3 . In the case where the first vapor permeable layer 3 includes the hydrolyzable material spots 10 , exposure of these spots 10 to the free flowing liquid (e.g., water, exudates) in growing amounts triggers disintegration (dissolving) of the hydrolyzable parts of the first vapor permeable layer 3 , where this disintegration adaptively occurs generally over only the heavily exuding parts of the wound site and not over the non-exuding or lightly exuding parts. In one variation, the absorbent pad 2 is provided with an anisotropic absorbency profile, for example at least partly up in the upper heights of the absorbent pad 2 so that the liquids from the heavily exuding parts of the wound site are inhibited from cross flowing laterally through the absorbent pad 2 to cause unintended disintegration of the hydrolyzable material spots 10 that are disposed over the drier micro-zones of the wound site. As a result, the drier micro-zones are prevented from becoming too dry due to excessive vapor exhaust (into the ambient) over their respective areas while the heavily exudating micro-zones of the wound site are prevented from becoming too wet thanks to the automatically increased vapor exhaust rates (into the ambient) caused by selective disintegration of the hydrolyzable material spots 10 that are disposed over the wetter micro-zones. In one embodiment, the hydrolyzable material spots 10 are not homogenous over each micro-zone but rather distributed as faster dissolving (more readily disintegrating) and more slowly dissolving spots 10 so that the automatically induced increase of MVTR will be automatically proportional to the length of time that the spots 10 of different hydrolyzing rates are exposed to hydrolyzing liquid and or to the concentration levels and/or chemistries (e.g., alkalinity) of the locally present hydrolyzing liquids. In other words, once the vapor exhaust rate of a given micro-zone increases to match the liquid production rate of its underlying portion of the wound site, the liquid concentration levels in that subregion drop so as to no longer expose the remaining spots 10 (those with slower hydrolyzing rates) to a hydrolyzing concentration of the liquid and the automatic process of progressively disintegrating more and more of the harder-to-hydrolyze material spots 10 automatically comes to a substantial stop. Thus each micro-zone of the wound site is automatically kept from becoming either too wet or too dry.
In the case of the spacer-including structures of FIGS. 5-6 , even if a given micro-zone in the wound site is both small in area and high in exudation rate, when the excess liquid crosses through the first vapor permeable and also converted-into-being a liquid permeable layer 3 , the permeating-through liquid spreads out to cover a larger lateral surface area by passing through the open cell pores of the spacer layer(s) 12 and/or 17 so that the spread out liquid is provided with a larger upper surface area from which its vapors may evaporate into the ambient by way of the liquid impermeable but vapor permeable layer 4 . In other words, since the second vapor permeable layer 4 is liquid impermeable, when the liquid gets into the natural capillaries or gaps, formed by spacer 12 between the first and second vapor permeable layers 3 and 4 , the liquid spreads out laterally. Then, however, the liquid impermeable layer 4 blocks the liquid from leaking out to the outside of the dressing. However, because of the MVTR of the second vapor permeable layer 4 is high, the evaporation rate of water vapor through the upper, second vapor permeable layer 4 sharply increases due to the expanded lateral surface area provided for such evaporation and as a consequence, this reduces the accumulation rate of liquids in portions of the absorbing core 2 that overlie heavily exudating micro-zones of the wound site even if those heavily exudating micro-zones, on their own, have relatively small surface areas.
By providing the first vapor permeable layer 3 of FIG. 6 as being made of a combination of two or more spaced apart soluble films 15 and 16 with porous spacers in between, a more gradual increase of the rate of water vapor evaporation from the dressing may be provided for. More specifically, the rising liquid spreads out laterally in area by a first proportional amount when it reaches the lower spacer layer 17 and then the reduced concentration of liquid controls the subsequent disintegration of the hydrolyzable material spots 10 (not shown) of permeable layer 16 . Yet more specifically, a time delay function may be provided wherein; if the wound exuding intensity was high for a short time immediately after the wound was created and then it later becomes much reduced, then only one layer 15 is dissolved by immediate exposure to the high concentrations of exudating liquid, and due to time delay in the liquids advancing to the next successive layer 16 , its respective hydrolyzable material spots 10 ′ (not shown) will remain more intact and thus prevent too high of a water evaporation rate from developing where such a too-high of an evaporation rate can lead to undesired wound part over-desiccation.
The material of the first vapor permeable layer 3 may form a viscous liquid when it is fully disintegrated by the hydrolyzing liquid(s) of sufficient concentration. After the hydrolyzing liquid(s) recede (due to evaporation of their water component for example), the left-behind viscous liquid formed by the fully dissolved hydrolyzable material spots 10 (not shown) is confined to remaining between, and drying out between the absorbing pad 2 and the second vapor permeable, but liquid impermeable layer 4 . If the intensity of wound exudates discharge rate next becomes reduced, the dried out remnants of the viscous liquid will, upon completion of their drying out process, automatically form a nonporous film that works to reduce further water vapor loss from the absorbing pad 2 at that spot and ultimately reduce moisture loss from the less-exuding wound bed thus automatically providing for a moist environment for the underlying wound site subregions even if beforehand, those subregion were heavily exuding ones and now they are less exuding ones. Small pores of the spacers 12 , 17 and the bonding layer between the absorbing pad 2 and the first vapor permeable layer 3 help to distribute the high viscous liquid more uniformly by locking the liquid in the pores. That results in forming more uniform, vapor blocking films as drying of the viscous liquid pools occurs.
When the lateral spacer layers (e.g., 12 and/or 17 ) are present, even if the first vapor permeable layer 3 is dissolved as a small spot only over a small, but heavily exuding part of the wound site, the rising column of exudate liquid will be driven up by capillary forces through the one small spot so as to be is quickly spread out laterally into a much larger lateral area between the first and second vapor layers 3 and 4 by action of the one or more spacer layers. This process significantly increases the area of evaporation through the second vapor permeable layer 4 . In other words, the relatively high MVTR of the second vapor permeable but liquid impermeable layer 4 combined with the larger evaporation surface area provided to the laterally spreading out portions of the rising column of liquid exudate provides a relatively high water evaporation rate, that then automatically reduces liquid accumulation in the absorbing core 2 and increases the useful wear time of the dressing 1 . As a consequence, dressings in accordance with the present disclosure need not be changed as often as the non-adaptive traditional dressings and costs of providing health care services may be significantly reduced.
By spacing the edge of the first vapor permeable layer 3 laterally inward relative to the dressing 1 edge (e.g., FIG. 3 ), the healthy skin around the wound site is preserved and the wear time of the dressing may therefore be increased. One of reason for frequent dressing changes may be that undesired leakage of exudates from the dressing periphery (edge) tends to damage the surrounding healthy skin. However, in the embodiments where the first vapor permeable layer 3 is spaced inward from the dressing edge, lateral spreading of exudate liquid between the layers 3 and 4 is blocked from occurring at the dressing edge. This prevents undesirable leakage of a potentially corrosive and infectious liquid (e.g., bacteria containing exudate) from the dressing edge where such leakage may then require more frequent wound cleanings and more frequent change of the dressing even before the absorbing core 2 reaches the limits of its absorbing capacity. In other words, the full exudate absorbing capacity of the absorbent pad 2 may be exploited due to a combination of advantageous operations of the here disclosed, automatically-adaptive wound dressing 1 . Excess moisture is quickly evaporated away as needed so that the absorbent pad 2 does not become prematurely saturated with water and damaging leakage of exudate to the healthy skin surrounding the wound site is prevented so that the frequency of dressing changes may be reduced. In the mean time, the absorbent pad 2 collects and stores the non-water components of the wound site exudates to basically the full exudate absorbing capacity of the absorbent pad material. Hence, the absorbing capacity is efficiently utilized to its full extent.
It is possible for the laterally spreading liquid between the first and second vapor permeable layers 3 and 4 to fully disintegrate the first vapor permeable layer 3 if the latter layer is fully hydrolyzable. That may result in undesirable delamination of dressing layers and loss of dressing integrity. Therefore in at least some of the illustrated embodiments (e.g., FIG. 2 ), the non-hydrolyzable (e.g., water resistant) segments 11 are provided so as to define an integrity maintaining mesh that keeps the first vapor permeable layer 3 well bonded to the underlying absorbing pad 2 and keeps the second vapor permeable layer 4 also bonded to the structure, thus preventing loss of dressing integrity. Although not shown in the other figures, it is to be understood that the concept of the integrity maintaining mesh 11 is equally applicable in those other embodiments. Alternatively or additionally the illustrated bonding in FIG. 4 of the second vapor permeable layer 4 directly to the absorbing pad 2 through the provided bonding openings 7 provides another means of maintaining dressing integrity. One or both of these integrity maintaining techniques may be used in the others of the illustrated embodiments.
If the first vapor permeable layer 3 is made of a material that is soluble only in warm water (temperature >25° C.), then the triggering of dissolution of the first vapor permeable layer is the results of the simultaneous effects of two factors: presence of free flowing liquid between the superabsorbent particles and fibers, and the temperature >25° C. (preferably 28-32° C.) of the first vapor permeable layer 3 .
A wound bed tissue temperature is close to the normal human body temperature of 36.6° C. Moreover, the fibrous or foam structure of the absorbing pad 2 defines is a relatively good thermal insulator. As a result, a significant temperature gradient tends to develop between the wound bed tissue and the first vapor permeable layer 3 ; for example with temperature dropping from 36.6° C. (or higher if the patient has a fever) to ambient room temperature as vertical distancing away from the wound bed tissue and closer to the vapor-permeable/liquid-impermeable layer 4 progresses for rising droplets of exudate liquid. As a result, if no warm exudate rapidly rises through the absorbent pad 2 , the temperature of the first vapor permeable layer 3 remains close to the ambient temperature (usually room temperature 18-22° C.) and the automatically-variable permeability layer 3 is not converted into it high MVTR mode. On the other hand, if the wound site is heavily exuding warm liquid and that warm (above room temperature) liquid rapidly reaches the first vapor permeable layer 3 , the latter layer 3 quickly disintegrates at that spot and allows for high rates of vapor release.
When all the absorbed liquid is bounded to superabsorbent particles and fibers and no free flowing water has yet formed, there are still a lot of air in the empty cells between fibers and particles of the absorbing pad 2 , the thermal insulation characteristics of the pad 2 are preserved and a significant difference in temperature continues to exist between the wound bed and the first vapor permeable layer 3 temperature. This maintained thermal insulation helps to assure that a correspondingly lower temperature is maintained at least for a while for parts of the first vapor permeable layer 3 that are disposed over non-exuding or low-exuding zones of the wound site. Accordingly, even if a column of warm exudate breaks through one part of layer 3 and spreads laterally between the first and second layers, 3 and 4 , and over the non-exuding or lesser exuding parts of the wound site, a cooling of the upwelling warm and spreading out exudate occurs due to water evaporation and heat conductivity to the ambient air through the liquid-impermeable but vapor breathing (LIVB) layer 4 and also due to thermal inertia whereby the laterally spaced apart areas of layer 3 are initially kept cool helps to prevent undesired disintegration of the first vapor permeable layer 3 over the these non- or less-exuding parts in spite of the presence of laterally spreading out liquid between the first and second layers, 3 and 4 , and over these parts of the wound dressing. In other words, the temperature-dependent disintegrating characteristics of the automatically-variable permeability layer 3 help to provide for the following: a) to continue providing a controlled moist air environment over the non-exuding parts of the wound due to the still intact first vapor permeable layer 3 above them; b) to reduce the probability of over-wetting of non-exuding wound parts and/or peri-wound skin and/or surrounding healthy skin due to the blocking of undesired leakage of the excessive liquid from the heavily exuding wound part and into contact with the drier parts; d) to reduce or minimize the probability of infection or re-infection of the non-exuding (e.g., more healed) wound parts and peri-wound skin due to bacteria being transferred together with the spread out exudate liquid from the exuding wound part.
Referring to FIG. 7 , shown here is another embodiment, similar to that of FIG. 5 except that in FIG. 7 , a second liquid absorbing layer 22 is disposed above and in contact with the automatically-variable permeability providing (AVPP) layer 3 . The second liquid absorbing layer 22 may be made of same or similar materials as that the first liquid absorbing layer 2 (a.k.a. absorbent pad 2 ) and/or of different materials. The second liquid absorbing layer 22 may be of a homogeneous composition laterally thereacross and/or vertically therethrough or it may vary in composition and/or absorbency characteristics either laterally thereacross, or vertically therethrough or in both senses. The thickness and/or absorbency capacity of the second liquid absorbing layer 22 need not be the same as that of the first liquid absorbing layer 2 (a.k.a. absorbent pad 2 ) and at least in one embodiment, the second liquid absorbing layer 22 is thinner and has a lower absorbency capacity.
One possible function for the second liquid absorbing layer 22 is to draw fluids (e.g., permeability altering liquids and/or vapors) away from the top side of the automatically-variable permeability providing (AVPP) layer 3 such that the permeability of AVPP layer 3 is controlled essentially by the concentration, amounts and/or chemistries of the fluids (e.g., permeability altering liquids and/or vapors) transmitted to its lower side by the first liquid absorbing layer 2 (a.k.a. absorbent pad 2 ) and not substantially by fluids that appear near the upper side of the AVPP layer 3 . With that said, it is nonetheless within the present contemplation of the disclosure that in an alternate embodiment, fluid concentrations at the upper side of the first AVPP layer 3 (e.g., those representative of humidity in the ambient air) do alter the permeability of the first AVPP layer 3 (or alternatively of a second AVPP layer such as layer 16 of FIG. 6 ). In the case where the function of the second liquid absorbing layer 22 is to draw fluids vertically away from the upper surface of the first AVPP layer 3 of FIG. 7 , the absorbency of the material in the second liquid absorbing layer 22 may increase as one progresses vertically up through that layer 22 as shown in FIG. 7 . Capillary action may quickly pull permeability-affecting fluids away from the top side of the first AVPP layer 3 and towards proximity with the liquid-impermeable but vapor breathing (LIVB) layer 4 above it so that vapors from the vertically drawn up fluids exhaust into the ambient air by way of LIVB layer 4 . As in the case of FIG. 6 , it is within the contemplation of the present disclosure to have two or more spaced apart automatically-variable permeability providing (AVPP) layers (e.g., like 15 and 16 of FIG. 6 ), where in the case of FIG. 7 (or that of next described FIG. 8 ) the second AVPP layer (not shown in FIGS. 7-8 ) is disposed above the second liquid absorbing layer 22 (and/or above the lateral fluids dispersing layer 17 of FIG. 8 ). That second AVPP layer (not shown in FIGS. 7-8 ) would respond variably to the concentration, amounts and/or chemistries of the fluids (e.g., permeability altering liquids and/or vapors) transmitted to its lower side by the second liquid absorbing layer 22 (and/or the lateral fluids dispersing layer 17 of FIG. 8 ).
Referring to FIG. 8 , shown here is a further embodiment, similar to that of FIG. 7 except that in FIG. 8 , a lateral fluids dispersing layer 17 (e.g., similar to 17 or 12 of FIG. 6 ) is provided above the second liquid absorbing layer 22 . Once absorbing layer 22 has drawn fluids vertically up and away from the first AVPP layer 3 , the lateral fluids dispersing layer 17 distributes those vertically transmitted fluids (e.g., liquids and/or vapors) laterally over a wider surface area so that vapors of these may more quickly be exhausted into the ambient air by way of liquid-impermeable but vapor breathing (LIVB) layer 4 .
It is to be appreciated that the above are merely illustrative examples and that those skilled in the art, after having appreciated the present disclosure, will be enabled into seeing many additional variations. In general, one of the aspects taught herein is that one or more automatically-variable permeability providing (AVPP) layers like 3 and/or 15 - 16 may be provided above a wound site having respective micro-zones that exhibit different tissue types (e.g., heavily exuding, lightly exuding, epithelializing, etc.); that fluids representative of the current states of those respective micro-zones may be vertically transmitted up to corresponding sub-portions of at least the first AVPP layer 3 where the first AVPP layer 3 is structured to variably alter its permeability in the corresponding sub-portions according to the concentration, amounts and/or chemistries of the fluids (e.g., permeability altering liquids and/or vapors) transmitted at least to its lower side, and as a result; a wound site treatment mechanism is provided that variably responds to the tissue-type representing fluidic signals sent to it from the respective micro-zones of the wound site below.
WORKING EXAMPLES
Example 1
A wound dressing in accordance with the disclosure was made by laminating of the following layers: 1) a wound contact layer 61 made of cross-linked polyvinyl alcohol fibers, the polymer was blended with antimicrobial additive polyhexamethylene biguanide (PHMB) 0.3 w %, the layer thickness was 150 microns, the layer density was 0.1 g/cm3, the fiber diameter range was 0.5-2 micron; 2) the absorbent pad 2 was made of polyester fibers with super-absorbent polymer particles (material being designated as WoundFelt™ marketed by National Nonwoven, Inc, Easthampton, Mass.), the layer thickness was 1.2 mm; 3) the first vapor permeable layer 3 was made of polyvinylpyrrolidone (marketed by Scientific Polymers, Inc, USA), had a thickness of 150 microns, an initial MVTR of 400 g/m2/24 hours when dry; 4) the second vapor permeable layer 4 was made of polyurethane high MVTR film (Bioflex™, marketed by SCAPA corporation, USA), had a film thickness of 25 microns, an MVTR of 2500 g/m2/24 hours). The layers 61 , 2 , 3 and 4 were permanently bonded to each other by patterned pressure sensitive adhesive (Rx560U™, marketed by SCAPA corporation, USA). The size of the so-fabricated dressing was 100×100 mm, the shape was a square with rounded corners having a radius of 15 mm.
Example 2
The wound dressing per Example 1 and further modified such that the absorbent pad 2 contained a pre-charge of sterile water at a density of 0.15 g/cm2 and glycerin at 0.03 g/cm2.
Example 3
The wound dressing per Example 2 further modified such that the first vapor permeable layer 3 was made of two polyvinylpyrrolidone films (marketed by Scientific Polymers, Inc, USA) each having a thickness of 150 microns, and an MVTR of 400 g/m2/24 hours when dry. The films were bonded to each other by a porous adhesive (marketed by Adhesive Research, Inc., Glen Rock, Pa.) having a thickness of 50 microns, a pore size of 20-250 microns, and an open area percentage equal to about 40%.
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, use of equivalent functional couplings for couplings described herein, and/or use of equivalent functional steps for steps described herein. Such insubstantial variations are to be considered within the scope of what is contemplated here. Moreover, if plural examples are given for specific means, or steps, and extrapolation between and/or beyond such given examples is obvious in view of the present disclosure, then the disclosure is to be deemed as effectively disclosing and thus covering at least such extrapolations.
Reservation of Extra-Patent Rights, Resolution of Conflicts, and Interpretation of Terms
After this disclosure is lawfully published, the owner of the present patent application has no objection to the reproduction by others of textual and graphic materials contained herein provided such reproduction is for the limited purpose of understanding the present disclosure of invention and of thereby promoting the useful arts and sciences. The owner does not however disclaim any other rights that may be lawfully associated with the disclosed materials, including but not limited to, copyrights in any computer program listings or art works or other works provided herein, and to trademark or trade dress rights that may be associated with coined terms or art works provided herein and to other otherwise-protectable subject matter included herein or otherwise derivable herefrom.
If any disclosures are incorporated herein by reference and such incorporated disclosures conflict in part or whole with the present disclosure, then to the extent of conflict, and/or broader disclosure, and/or broader definition of terms, the present disclosure controls. If such incorporated disclosures conflict in part or whole with one another, then to the extent of conflict, the later-dated disclosure controls.
Unless expressly stated otherwise herein, ordinary terms have their corresponding ordinary meanings within the respective contexts of their presentations, and ordinary terms of art have their corresponding regular meanings within the relevant technical arts and within the respective contexts of their presentations herein. Descriptions above regarding related technologies are not admissions that the technologies or possible relations between them were appreciated by artisans of ordinary skill in the areas of endeavor to which the present disclosure most closely pertains.
Given the above disclosure of general concepts and specific embodiments, the scope of protection sought is to be defined by the claims appended hereto. The issued 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. | An automatically self-adjusting variable permeability providing (AVPP) layer is provided over and in operative interaction with a wound site containing a wound to the integumentary system of a living creature such as the skin of a human patient. The AVPP layer has the capability of automatically changing in respective fluid permeability characteristics provided by respective subregions of the AVPP layer where the changes are in reaction to extant or changed conditions in corresponding micro-zones of the wound site. The automatic self-adjusting behaviors of the respective subregions of the AVPP layer can include providing a faster rate of vapor removal for micro-zones of the wound site that are too wet and providing a slower rate of vapor removal or essentially no vapor removal for micro-zones of the wound site that are too dry. | 0 |
CROSS REFERENCE TO OTHER APPLICATIONS
[0001] This application is a continuation of co-pending U.S. patent application Ser. No. 11/999,505 (Attorney Docket No. LINKP019), entitled STORAGE MEDIA DEFECT DETECTION filed Dec. 5, 2007 which is incorporated herein by reference for all purposes.
BACKGROUND OF THE INVENTION
[0002] Storage media, including magnetic media such as hard disk drives, include defects that result from manufacturing (e.g., present in a brand new or virgin disk drive) and/or from the environment or usage over time. At a defect location, data cannot be reliably written to the media. For example, when reading data at a defect location, an overly strong signal (e.g., that saturates a circuit), a weak signal, or no signal at all may be read. Defect scanners are used to create a map of defect locations so that these locations are not written to or read from. Typically, a defect scan is performed on a new disk drive and a map is obtained in this way.
[0003] Current defect scanning techniques are inefficient. Typical defect maps have limited resolution and can only indicate defect locations down to the sector level. In other words, typical defect scanners are only able to determine in which sector a defect is located. Even though a defect region may be much smaller than a sector, the entire sector is unused, which is inefficient. In addition, typical defect scanners require peak samples (e.g., a local maximum) as input. This means that the signal timing must first be acquired (i.e., so that the location of the peaks is known), which requires a timing loop and takes additional time. In addition, defects that occur before the timing is acquired (e.g., in a preamble or beginning portion) are not detected. As such, improved defect detection techniques would be useful.
BRIEF DESCRIPTION OF THE DRAWINGS
[0004] Various embodiments of the invention are disclosed in the following detailed description and the accompanying drawings.
[0005] FIG. 1 is a block diagram illustrating an embodiment of a system for detecting media defects.
[0006] FIG. 2A is a diagram illustrating an example of a read-back waveform and peak samples.
[0007] FIG. 2B is a diagram illustrating an example of a read-back waveform and samples with an arbitrary phase offset.
[0008] FIG. 3 is a flow chart illustrating an embodiment of a process for detecting a defect associated with amplitude.
[0009] FIG. 4 is a flow chart illustrating an embodiment of a process for detecting a defect associated with a DC component.
[0010] FIG. 5 is a flow chart illustrating an embodiment of a process for detecting a defect associated with phase.
[0011] FIG. 6 is an example of a plot of accumulated phase versus phase chunks.
[0012] FIG. 7 is a flow chart illustrating an embodiment of a process for fine tuning N for a defect detection system.
DETAILED DESCRIPTION
[0013] The invention can be implemented in numerous ways, including as a process, an apparatus, a system, a composition of matter, a computer readable medium such as a computer readable storage medium or a computer network wherein program instructions are sent over optical or communication links. In this specification, these implementations, or any other form that the invention may take, may be referred to as techniques. A component such as a processor or a memory described as being configured to perform a task includes both a general component that is temporarily configured to perform the task at a given time or a specific component that is manufactured to perform the task. In general, the order of the steps of disclosed processes may be altered within the scope of the invention.
[0014] A detailed description of one or more embodiments of the invention is provided below along with accompanying figures that illustrate the principles of the invention. The invention is described in connection with such embodiments, but the invention is not limited to any embodiment. The scope of the invention is limited only by the claims and the invention encompasses numerous alternatives, modifications and equivalents. Numerous specific details are set forth in the following description in order to provide a thorough understanding of the invention. These details are provided for the purpose of example and the invention may be practiced according to the claims without some or all of these specific details. For the purpose of clarity, technical material that is known in the technical fields related to the invention has not been described in detail so that the invention is not unnecessarily obscured.
[0015] FIG. 1 is a block diagram illustrating an embodiment of a system for detecting media defects. Examples of media include storage media, such as magnetic media and hard disk drives. There are a number of different types of defects, including the following:
[0016] (1) Drop in/drop out defects are associated with an amplitude boost or loss defects of greater than approximately 5% or more compared to a normal or ideal signal.
[0017] (2) Shallow defects are associated with an amplitude boost or loss of approximately 5% or less compared to a normal or ideal signal.
[0018] (3) Thermal asperity (TA) defects are associated with a sudden DC (direct current) jump or offset.
[0019] (4) Timing defects are associated with a sudden phase jump in a signal. This includes changes in frequency, such as a pulse becoming narrower or wider.
[0020] In the example shown, system 100 is shown to include computation block 102 , accumulators 104 , and detector 106 . ADC (analog to digital converter) samples are read from a storage device and provided as input to computation block 102 . Computation block 102 computes an amplitude, a DC component, and/or a phase using the ADC samples. In various embodiments, the same or a different number of samples are used to compute the amplitude, the DC component, and/or the phase. In some embodiments, 4 samples are used to compute the amplitude, the DC component, and the phase. The amplitude, the DC component, and/or the phase are output from computation block 102 and provided as input to accumulators 104 .
[0021] Accumulators 104 (which may include one or more accumulators) are used to compute a moving average of the amplitude, the DC component, and the phase over N A , N D , and N P samples, respectively. (N A , N D , and N P are the “N's” referred to in FIG. 1 .) In this example, accumulators 104 output an accumulated amplitude, an accumulated DC component, and an accumulated phase, which are provided as input to detector 106 . Detector 106 uses the accumulated amplitude, the accumulated DC component, and the accumulated phase and thresholds T A , T D , and T P , respectively, to detect the various types of defects. Accumulators 104 are optional and in some embodiments, one of more of the amplitude, the DC component and the phase are not averaged.
[0022] In some embodiments, detector 106 compares a defect value with a threshold to determine whether a defect is present. In some embodiments, the defect values and/or thresholds are different for different defect types. For example, for a thermal asperity defect, the defect value is the accumulated DC component |D acc | and the threshold is T D . If |D acc |>T D , then a thermal asperity defect is detected. More detailed examples are described below.
[0023] The outputs of detector 106 are defect flags corresponding to the locations of the defects. In some embodiments, the defect flags are stored in a defect map that is used by the hard disk controller (HDC) so it knows not to read or write to the defect locations.
[0024] Using the techniques described herein, defects associated with any of the defect types can be detected all in one shot, or simultaneously (i.e., in parallel) as opposed to sequentially (i.e., one at a time). Simultaneous detection is faster than sequential detection. In addition, the thresholds and/or defect scan resolutions (associated with N) for each defect type are programmable inputs. In some embodiment, system 100 is implemented entirely in digital circuitry and analog circuitry is not used.
[0025] FIG. 2A is a diagram illustrating an example of a read-back waveform and peak samples. A read-back waveform is a signal read-back from a storage device, such as a hard disk drive. In the example shown, diagram 200 shows read-back waveform 202 , circled peak ADC samples at x 2 , x 4 , x 6 , etc, and circled zero-crossing samples at x 1 , x 3 , x 5 , etc. A pattern of “1100” is repeatedly written to a hard disk in order to obtain read-back waveform 202 . In some embodiments, some other (e.g., repeated) pattern is used. The ideal amplitude of read-back waveform 202 is 16, as indicated in FIG. 2A . An example of a drop in/drop out defect is shown between x 9 and x 17 . In this case, the amplitude loss is 50% (a drop in amplitude from 16 to 8).
[0026] In some other defect scanners, the samples used to detect the defect area shown are required to be peak samples as shown at x 2 , x 4 , x 6 , etc. As used herein, “peak samples” are samples that coincide with the peaks of the signal. Peak sampling corresponds to a sampling phase offset equal to zero. This means that before a defect can even be detected, timing acquisition (which uses a timing loop) needs to be performed in order to determine the location of the peaks and be able to sample at the peaks. Defects that occur or coincide with the portions of a read back waveform used to perform timing acquisition are not detected. For example, timing acquisition may be performed between x 1 and x 12 , in which case the portion of the defect area between x 9 and x 12 would not be detected. Also, by using peak samples x 2 , x 4 , x 6 , etc. only, and skipping zero-crossing samples such as x 1 , x 3 , x 5 , etc., the detection is more vulnerable to noise than fully using all samples x 1 , x 2 , x 3 , x 4 , etc. Thus, it would be desirable to have a defect detection technique that does not require timing acquisition to first be performed and/or does not require use of a timing loop for defect detection. Such techniques are disclosed herein.
[0027] FIG. 2B is a diagram illustrating an example of a read-back waveform and samples with an arbitrary phase offset. Sampling with an arbitrary phase offset means that the sampling starts at an arbitrary time, and not necessarily at zero phase offset, which corresponds to peak sampling. Any appropriate phase offset may be used in various embodiments. In the example shown, diagram 204 shows read-back waveform 202 and circled ADC samples at y 1 , y 2 , y 3 , y 4 , y 5 , y 6 , etc. A pattern of “1100” is repeatedly written to a hard disk in order to obtain read-back waveform 202 . A drop in/drop out defect area is shown between y 8 and y 17 . Using the defect detection techniques described herein, sampling may start at an arbitrary time and samples y 1 , y 2 , y 3 , y 4 , y 5 , y 6 , etc. are not required to be peak samples. This means that a defect can be detected starting with the first sample y 1 . In other words, a defect can be detected immediately after the start of sampling. The defect detection techniques described herein do not require timing acquisition to first be performed nor do they require use of a timing loop.
[0028] FIG. 3 is a flow chart illustrating an embodiment of a process for detecting a defect associated with amplitude. Examples of defects associated with amplitude include drop in/drop out defects and shallow defects.
[0029] The process may be implemented by system 100 . At 302 , ADC samples are received. For example, computation block 102 receives ADC samples. If a pattern of “1100” is written to the hard disk drive (i.e., so that the read-back waveform is a sine wave), and y 1 -y 4 are four ADC samples of the read-back waveform, then:
[0000] y 1 =A sin(θ)
[0000] y 2 =A cos(θ)
[0000] y 3 =−A sin(θ)
[0000] y 4 =−A cos(θ)
[0030] where A is the amplitude.
[0031] At 303 , an amplitude is computed. For example, computation block 102 computes an amplitude. If the sampled signal is a sine wave, the amplitude may be computed as follows:
[0000] A =(( y 1- y 3) 2 +( y 2- y 4) 2 ) 1/2
[0032] where A is the amplitude. In some embodiments, a look up table is used for this computation. In various embodiments, various equations may be used to compute the amplitude.
[0033] At 304 , amplitudes A i are accumulated or averaged to remove white noise or AWGN (additive white Gaussian noise) effects. For example, accumulators 104 may accumulate the amplitudes. In some embodiments, amplitudes are accumulated as follows:
[0000] A acc =(Σ A i )/(¼ N A )
[0034] where:
[0035] A acc is the accumulated amplitude
[0036] Σ is a summation from i=1 to ¼ N A
[0037] A i is the i th amplitude
[0038] N A is the number of samples over which to average
[0039] If A is computed using 4 samples y 1 -y 4 , then A i can be computed in a variety of ways. For example:
[0000] A 1 =(( y 1- y 3) 2 +( y 2- y 4) 2 ) 1/2
[0000] A 2 =(( y 5- y 6) 2 +( y 7- y 8) 2 ) 1/2
[0000] A 3 =(( y 9- y 10) 2 +( y 11- y 12) 2 ) 1/2
[0040] etc.
[0041] In this example, every 4 samples, one amplitude A i is computed. Therefore, in this example, Σ is a summation from i=1 to ¼ N A .
[0042] Any similar or equivalent technique for removing white noise or AWGN effects may be used. For example, just ΣA i may be taken and N A accounted for later.
[0043] At 306 , it is determined whether the accumulated amplitude is above or below the ideal amplitude by more than a threshold. In other words, it is determined whether:
[0000]
A
acc
>A
ideal
+T
A
[0000] or
[0000]
A
acc
<A
idea
−T
A
[0044] where
[0045] A ideal is the ideal amplitude
[0046] T A is a threshold
[0047] There are two types of amplitude defects:
[0048] (1) Drop in/drop out defects are associated with an amplitude boost or loss defects of greater than approximately 5% compared to a normal or ideal signal.
[0049] (2) Shallow defects are associated with an amplitude boost or loss of approximately 5% or less compared to a normal or ideal signal.
[0050] For drop in/drop out defects, T A =5% of A ideal In various embodiments, other percentages besides 5% may be used to compute the amplitude. For example, to detect amplitude defects of 20%, T A =20% of A ideal may be used.
[0051] In some cases, multiple thresholds can be set during amplitude defect detection. In such cases, the output of detector 106 indicates the range of percentages associated with the amplitude defect at a fine amplitude resolution (different from the defect location resolution), where the fine amplitude resolution is associated with N A . For example: T A1 =5% of A ideal , T A2 =10% Of A ideal , T A3 =15% of A ideal , etc. If A acc >A ideal +T A1 but A acc <A ideal +T A2 , the output of detector 106 indicates that the amplitude defect is between 5% to 10%.
[0052] For shallow defects, T A =P shallow % Of A ideal
[0053] where P shallow <5%
[0054] In some embodiments, N A is different for the two types of amplitude defects. N A for shallow defects may be larger because more white noise needs to be removed in order to detect smaller amplitude defects.
[0055] If at 306 , it is determined that the accumulated amplitude is above or below the ideal amplitude by more than a threshold, then a defect is detected at 308 . For example, defect detector 106 may perform this determination. The defect location is associated with the samples used to compute the accumulated amplitude. Therefore, the defect resolution (i.e., the resolution of the defect location) is N A . In some embodiments, information about the defect, such as the location of the defect in media, is recorded or written (e.g., to a defect map).
[0056] The process returns to 302 and the next set of ADC samples is analyzed.
[0057] As previously described with respect to FIG. 1 , a defect value is compared with a threshold to determine whether there is a defect. In this example, the defect value is the accumulated amplitude A acc and the threshold is T A .
[0058] FIG. 4 is a flow chart illustrating an embodiment of a process for detecting a defect associated with a DC component. Examples of defects associated with a DC component include thermal asperity (TA) defects.
[0059] The process may be implemented by system 100 . At 402 , ADC samples are received. For example, computation block 102 receives ADC samples. For example, y 1 -y 4 are four ADC samples of the read-back waveform when a pattern of “1100” is written to the hard disk drive (i.e., so that the read-back waveform is a sine wave), as previously described.
[0060] At 403 , a DC component is computed. For example, computation block 102 computes a DC component. If the sampled signal is a sine wave, the DC component may be computed as follows:
[0000] D=y 1 +y 2 +y 3 +y 4
[0061] where D is the DC component. In various embodiments, various equations may be used to compute the DC component.
[0062] At 404 , DC components D i are accumulated or averaged to remove white noise or AWGN effects. For example, accumulators 104 may accumulate the DC components. In some embodiments, DC components are accumulated as follows:
[0000] D acc =(Σ D i )/(¼ N D )
[0063] where:
[0064] D acc is the accumulated DC component
[0065] Σ is a summation from i=1 to ¼ N D
[0066] D i is the i th DC component
[0067] N D is the number of samples over which to average
[0068] Any similar or equivalent technique for removing white noise or AWGN effects may be used, some examples of which were described above.
[0069] At 406 , it is determined whether the magnitude of the accumulated DC component is above a threshold. In other words, it is determined whether:
[0070] |D acc |>T D
[0071] where T D is a threshold
[0072] If at 406 , it is determined that the accumulated DC component is above a threshold, then a defect is detected at 408 . For example, defect detector 106 may perform this determination. The defect location is associated with the samples used to compute the accumulated DC component. Therefore, the defect resolution is N D . In some embodiments, the location of the defect or other information associated with the defect is written or stored.
[0073] The process returns to 402 and the next set of ADC samples is analyzed.
[0074] As previously described with respect to FIG. 1 , a defect value is compared with a threshold to determine whether there is a defect. In this example, the defect value is the magnitude of the accumulated DC component |D acc | and the threshold is T D .
[0075] FIG. 5 is a flow chart illustrating an embodiment of a process for detecting a defect associated with phase. Examples of defects associated with phase include timing defects.
[0076] The process may be implemented by system 100 . At 502 , ADC samples are received. For example, computation block 102 receives ADC samples. For example, y 1 -y 4 are four ADC samples of the read-back waveform when a pattern of “1100” is written to the hard disk drive (i.e., so that the read-back waveform is a sine wave), as previously described.
[0077] At 503 , a phase is computed. For example, computation block 102 computes a phase. If the sampled signal is a sine wave, the phase component may be computed as follows:
[0000] P =arc tan(( y 1- y 3)/( y 2- y 4))
[0078] where P is the phase. In various embodiments, various equations may be used to compute the phase.
[0079] In some embodiments, a look up table is used for this computation. In some embodiments, if there is a frequency offset, the phase is unwrapped to maintain a linear plot of phase versus sample number, as describe more fully below.
[0080] At 504 , phases P i are accumulated or averaged to remove white noise or AWGN effects. For example, accumulators 104 may accumulate the phases. In some embodiments, phases are accumulated as follows:
[0000] P acc =(ρ P i )/(¼ N P )
[0081] where:
[0082] P acc is the accumulated phase
[0083] Σ is a summation from i=1 to ¼ N P
[0084] P i is the i th phase
[0085] N P is the number of samples over which to average
[0086] Any similar or equivalent technique for removing white noise or AWGN effects may be used, some examples of which were described above.
[0087] At 505 , a current accumulated phase is set equal to the accumulated phase. In other words:
[0000] P curr — acc =P acc
[0088] where P curr — acc is the current accumulated phase
[0089] At 506 , it is determined whether the difference between the current accumulated phase and the previous accumulated phase is above a threshold. In other words, it is determined whether:
[0000] ΔP acc >T P
[0000] where
[0000] Δ P acc =|P curr — acc −P prev — acc |
[0090] T P is a threshold
[0091] If 506 is being performed for the first time (i.e., this is the first iteration), then the comparison of ΔP acc >T P is skipped and the process proceeds to 507 , which is described below.
[0092] If at 506 , it is determined that the difference is above a threshold, then a defect is detected at 508 . For example, defect detector 106 may perform this determination. The defect location is associated with the samples used to compute the difference. Therefore, the defect resolution is N P .
[0093] At 507 , the previous accumulated phase is set equal to the current accumulated phase. In other words:
[0000] P prev — acc ←P curr — acc
[0094] where P prev — acc is the previous accumulated phase
[0095] The process returns to 502 and the next set of ADC samples is analyzed.
[0096] As previously described with respect to FIG. 1 , a defect value is compared with a threshold to determine whether there is a defect. In this example, the defect value is the difference between the current and previous accumulated phases ΔP acc and the threshold is T P .
[0097] FIG. 6 is an example of a plot of accumulated phase versus phase chunks. In this example, plot 600 shows unwrapped phase on the y-axis and chunk number on the x-axis. Each point is an accumulated phase over N P samples. Each chunk is N P samples. In other words, ΔP acc =|P curr — acc −P prev — acc | is the vertical between two consecutive points in plot 600 . As shown, the difference between any two consecutive points suddenly drops at or about chunk 602 and suddenly jumps at or about chunk 604 . The drop and jump are greater than the threshold T P and therefore a timing defect is detected between and/or at chunks 602 and 604 .
[0098] Each chunk corresponds to N P samples, where N P =40 in this example. (T is the period between samples.) The slope of the line is the frequency offset. If there is no frequency offset, the slope would be 0 (i.e., the line would be horizontal). In some embodiments, if there is a frequency offset, a phase unwrap circuit is used to unwrap the phase to make the plot linear.
[0099] FIG. 7 is a flow chart illustrating an embodiment of a process for fine tuning N for a defect detection system, such as system 100 . N is the number of samples over which an average is performed. This process may be used to fine tune N A , N D , or N P , for example. In this example, the goal is to obtain the minimum N that is required in order to detect a certain percentage (e.g., 100%) of the defects. The larger N, the greater the number of samples, and the more accurate the detection. The smaller N, the fewer the number of samples, and the higher the resolution of the location of the defects. If 4 samples are used to compute a defect value, then N is a multiple of 4.
[0100] At 702 , an initial N is selected. In some embodiments, the initial N is 1, which corresponds to no accumulation or averaging. At 703 , a signal with known defects is received and sampled. In some embodiments, an artificial signal is constructed by starting with an ideal signal and adding defects and AWGN. For example, to determine N A for detecting drop in/drop out defects, artificial (known) amplitude boosts and/or losses of 5% or more are added to the signal. In some embodiments, the artificial signal is pre-sampled and the artificial samples are received.
[0101] At 704 , defects are detected according to the process of FIG. 3 , 4 , or 5 , depending on which of N A , N D , or N P , respectively, is being fine tuned. For example, in system 100 , the artificial samples are provided as input to computation block 102 and detected defects are obtained at the output of detector 106 .
[0102] At 706 , it is determined whether all known defects were detected. For example, the output of detector 106 is compared with the known defects. If all defects were not detected, N is adjusted at 708 . For example, N is incremented by 1 . The process returns to 704 . If all defects were detected, then that N is output at 710 . The N that is output is the minimum N such that all defects are detected.
[0103] In some embodiments, it is acceptable to have some percentage other than 100% of defects detected, e.g., 99.999%. In such embodiments, at 706 , it is determined whether that percentage (e.g., 99.999%) of the known defects were detected.
[0104] In some embodiments, the process of FIG. 7 is performed for a variety of defect types and thresholds and tables of the minimum N to obtain 100% defect detection for different combinations of defect types and thresholds can be constructed.
[0105] Although the foregoing embodiments have been described in some detail for purposes of clarity of understanding, the invention is not limited to the details provided. There are many alternative ways of implementing the invention. The disclosed embodiments are illustrative and not restrictive. | Detecting a defect on a storage device is disclosed. Detecting includes receiving a signal read from a storage device, sampling the signal to obtain a set of signal samples, wherein the sampling starts at an arbitrary time, computing a defect value for a defect type using the set of signal samples, comparing the defect value with a threshold associated with the defect type, determining whether there is a defect of the defect type based at least in part on the comparison, and in the event that a defect is detected, outputting an indication associated with the defect. | 6 |
This invention relates to a bead release device for tire removal machines in general.
BACKGROUND OF THE INVENTION
For removing and mounting tires from and onto their respective wheel rims it is known to use suitable the removal machines which will not be described in detail herein.
To remove the tire the tire beads have to be previously separated from the respective bead-holding edges of the wheel rim.
Modern tire removal machines are provided with a bead release device for effecting this separation.
Bead release devices are known comprising an arm positioned to the side of the base of the respective tire removal machine and hinged to said base on a rear vertical axis.
Said arm is provided at its front with a bead release tool, commonly known as a blade, with which there is associated a locator positioned to the side of said base and arranged to act as a support for the wheel rim during the tire bead release.
Finally, between said arm and base there is a pneumatic cylinder-piston unit which is coupled to the arm with unilateral engagement.
Specifically, said coupling is achieved by a vertical pin which is rotatably mounted on said arm and is provided with a diametrical hole into which the rod of said cylinder-piston unit is slidingly inserted, said rod being provided with a terminal head for drawing said arm towards said locator.
The procedure for effecting bead release with said known devices is as follows.
At the commencement of a bead release operation the rod of the cylinder-piston unit is completely extended and the arm has rotated into its rest position, in which it is spaced apart from said locator.
The wheel (rim plus tire) is then placed upright resting against said locator, and the arm is made to approach the locator, with the bead release tool brought into contact with the tire bead a short distance from the bead-holding edge of the wheel rim.
During this approach the cylinder-piston unit remains in the preceding configuration, with the arm sliding along the (extended) rod of the cylinder-piston unit, so withdrawing from the terminal head of the rod.
After this approach the cylinder-piston unit is made to contract, its rod then dragging the arm and hence the bead release tool towards the wheel only after the rod head has made up the distance which separates it from the hinge pin between the rod and arm.
Basically, the actual bead release action begins only after the rod has undergone a certain idle travel, this idle travel resulting in the following drawbacks.
Firstly, said idle travel results in relatively long bead release times, which increase as the width of the wheel to undergo bead release increases.
Secondly, this idle travel results in wastage of compressed air. It will be apparent that such problems increase considerably if in order to separate a tire bead the bead release tool has to be positioned in different circumferential regions of the bead, this being necessary if the bead is tightly attached to the respective bead-holding edge and/or to the corresponding ridge.
SUMMARY OF THE PRESENT INVENTION
The main object of the present invention is to obviate the aforesaid problems within the context of a simple and rational construction.
To attain said object the invention provides a plurality of aligned equidistant identical notches in the end portion of the rod of the cylinder-piston unit, and a coupling member which is associated with the arm carrying the bead release tool and is arranged to engage said notches.
Said plurality of notches preferably consists of a saw-tooth rack, said coupling member consisting of a pawl of conjugate shape.
The coupling and release positions of said pawl are determined by suitable means, for example controlled by the operator, said coupling and release positions being preferably governed, according to an advantageous characteristic of the invention, by the contraction and elongation of the cylinder-piston unit.
All the objects of the invention are achieved by virtue of the aforesaid means, in that the idle travel of the rod of the cylinder-piston unit is eliminated whatever the width of the wheel to be subjected to bead release.
In this respect, when the arm has been rotated (manually) towards the base of the tire removal machine and the bead release tool has been rested against the tire bead, contracting the cylinder-piston unit results in instantaneous engagement between the pawl and the rack, with the result that the arm (and the bead release tool) is immediately pulled towards the tire removal machine (and towards the wheel to be subjected to bead release). The charcteristics and constructional merits of the invention will be apparent from the detailed description of a preferred embodiment thereof given hereinafter by way of non-limiting example with reference to the accompanying drawings.
Other objects and further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. It should be understood, however, that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus, are not limitative of the present invention, and wherein:
FIG. 1 is a top view of the invention associated with a tire removal machine and shown in the starting position for bead release of a relatively wide tire.
FIG. 2 is a view similar to the preceding, the invention being shown in the starting position for bead release of a relatively narrow tire.
FIG. 3 is a sectional plan view to a greater scale showing the mutual coupling means interposed between the rotating arm and the respective operating rod.
FIG. 4 is a section on the line IV--IV of FIG. 3 to a greater scale.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Said figures, and in particular FIGS. 1 and 2, show a tire removal machine, indicated by 100, which comprises basically a frame or base 1 from which there upwardly extends a column 2, at the top end of which there is a longitudinally slidable horizontal bar 3. Said bar 3 supports a height-adjustable vertical rod 4 which is provided lowerly with a tool (not shown) for removing and mounting tyres from and onto their respective wheel rims. Said tool lies above a rotatable horizontal plate 5 which in the case under examination comprises four angularly equidistant heads 55 which slide radially for gripping the wheel rims.
As is usual, said heads 55 are of the double action type, ie they grip the rims both from the inside and from the outside.
As can be seen, on one side wall of the base 1, namely that to the right in FIGS. 1 and 2, there is provided a horizontally extending elongate box member 77, at the opposing ends of which there are provided a front locator 8 and a rear vertical pin 6.
Said locator 8 acts as a support for the rim of a wheel 99 (upright) from which the bead is to be released, an arm 60 being hinged on said pin 6.
A bead release tool 66, commonly known as a blade and provided with a projecting lever 44, is hinged on a horizontal transverse axis to the front end of the arm 60.
The body of a single-acting cylinder-piston unit (not shown because it is of usual type) housed within the base is hinged to said box member 77 on a vertical axis 70.
The rod 9 of said cylinder-piston unit extends towards the central region of the arm 60 where the means according to the invention are provided for the mutual coupling of said rod 9 and arm 60 during bead release.
Said means are described hereinafter with reference to FIGS. 3 and 4.
As can be seen, said rod 9 terminates with a threaded portion 10 on which a coaxial prismatic bar 11 is screwed.
With the inner end of said bar 11 there is associated a locking nut 12 which is screwed onto said threaded portion 10, between said nut 12 and the box member 77 there being provided a cover 13, mounted to the box member 77. The cover 13 is cylindrical in shape having an aperture through which the rod 9 is slidably received.
Between said rod 9 and cover 13 there is interposed a sleeve 14 of elastic material such as rubber, the ends of which extend beyond those of the cover 13 (see FIG. 3). The purpose of said cover 13 is to mask the aperture (not shown) provided in the box member 77 for passage of the rod 9, the purpose of said sleeve 14 being to prevent noisy contact between the cover 13 and said nut 12 and box member 77.
The bar 11 is inserted, with an exact nut freely slidable fit, into a conjugate prismatic seat 110 provided in a block 15.
Said block 15 is housed within the arm 60, which is of channel cross-section with its mouth facing the base 1 (see FIG. 3).
The block 15 is hinged to the arm 60 on a vertical axis, which is indicated by 7 in all the accompanying figures and intersects the longitudinal axis of the bar 11. Specifically, said axis 7 is defined by two centrally holed coaxial discs 16 partly received in two conjugate recesses provided in the lower and upper faces of the block 15.
The projecting parts of said two discs 16 are received in respective holes 160 provided in the flanges of the arm 60, said discs 16 extending beyond the outer faces of said flanges.
Respective greater-diameter washers 161 rest against the outer ends of said discs 16, these latter and the washers 161 being torsionally fixed to the block 15 by at least two split pins 163 (FIG. 4).
Finally, the discs 16 and the washers 161 are axially locked by two through screws 162 screwed into the block 15.
As can be seen in FIG. 3, the bar 11 extends beyond the block 15, where it comprises a cap 17 the purpose of which is to prevent the block 15 withdrawing from the bar 11. Said cap 17 is provided with a damper ring 170, for example of rubber, the purpose of which is to prevent noisy contact between said block 15 and cap 17 when the arm 60 is rotated into its position of maximum opening. This latter is shown schematically in FIGS. 1 and 2 by dashed and dotted lines.
With reference to FIG. 3 it can be seen that a rack portion 111 is provided on that side of the bar 11 facing the pin 6 on which the arm 60 is hinged.
Said rack 11 is of the saw-tooth type, the teeth being inclined towards the base 1. In front of said rack 111 there is a pawl 18 consisting of an elongate flat profiled body virtually parallel to the bar 11 (FIG. 3). Said pawl 18 is received, practically as an exact fit, in a seat 180 (see FIG. 4) forming a lateral extension of the seat 110 within which the bar 11 slides.
The pawl 18 is pivoted to the block 15 on a transverse axis 19 parallel to the axis 7, and lies between the bar 11 and an opposing profiled support 20 fixed to the block 15 by screws 21. On that side of the pawl 18 facing the bar 21 there are provided, at that end closer to the cap 17, three saw-teeth 112 having the same shape and dimensions as those of the toothing of the rack 111.
It should be noted that the pawl 18 and rack 111 are formed of very hard material by microfusion.
In the illustrated example, the rack 111 is formed in one piece with the bar 11, however said rack 111 can be formed separately and then fixed to the bar 11 or rod 9.
As can be seen in FIG. 3, a compression spring 22 and a push rod 23 are provided on the opposite face of the pawl 18 on one and the other side of its pivot 19.
Said spring 22 is partly received in a recess in said pawl 18, its outer end resting against the support 20. The purpose of the spring is to urge the pawl 18 into its release position.
Said push rod 23 rests against a piston 24 which is slidingly received in a sealed manner within a hollow cylinder 25 which is fixed to the support 20. The purpose of the piston 24 is to urge the pawl 18 into its coupled position against the spring 22, there being provided between said piston 24 and cylinder 25 for this purpose a service chamber 26 into which a duct 260 opens.
This latter is connected to a compressed air source via suitable valve means.
In particular, according to an advantageous characteristic of the invention, the duct 260 is connected to the valve unit associated with that pedal of the tire removal machine 100 which controls the elongation/contraction of the cylinder-piston unit which operates the arm 60.
The pawl 18 can be coupled and released by equivalent means. What is important is that this coupling and release of the pawl is done in association with the contraction and elongation of said cylinder-piston unit.
The invention operates as follows.
On commencing a bead release operation, the rod 9 is completely extended and the arm 60 is rotated into its position of maximum opening (shown by dashed and dotted lines in FIGS. 1 and 2).
At the same time the chamber 26 is connected to discharge, the spring 22 maintaining the pawl 18 in its released position.
The wheel 99 to undergo bead release, which can be wide or narrow as shown in FIGS. 1 and 2 respectively, is rested against the locator 8 and the arm 60 is rotated towards this latter so that the tool is in contact with the bead of said wheel 99.
At this point the rod 9 is made to retract, resulting in instantaneous coupling of the pawl 18 to the rack 111 by virtue of the advancement of the piston 24, and in simultaneous pulling of the arm 60 and hence of the bead release tool 66.
On termination of bead release the rod 9 is made to extend, resulting in instantaneous connection of the chamber 26 to discharge and the simultaneous release of the pawl 18 by the effect of the spring 22.
After this the described cycle is repeated identically for the next bead release operation.
The merits and advantages of the invention are apparent from the aforegoing and from an examination of the accompanying figures.
Lastly, it should be noted that when the pawl 18 is in its released position (FIG. 3) the respective teeth 112 are at a short distance from the toothing of the rack 111, and have their points lying in a plane which is slightly inclined to the plane in which the pointed ends of the rack 111 lie.
Specifically, said two planes define an acute angle with its opening facing the cap 17.
This arrangement virtually completely eliminates any jamming or mutual slippage between the two toothings 111 and 112, which are perfectly aligned and copenetrating when the pawl 18 is coupled.
It should also be noted that the length of the rack 111 is such as to prevent excessive and inconvenient approach of the tool 66 to the locator 8 when the pawl 18 engages that end of the rack 111 close to the locator 8. Beyond said end the corresponding face of the bar 11 is perfectly smooth to enable the teeth 112 to slide along the bar when the wheel 99 undergoing bead release is fairly narrow.
The invention is not limited to that illustrated and described, but comprises all technical equivalents to the stated means and their combination, if effected within the context of the following claims. | A bead release device for tire removal machines comprises an arm (60) which at one end is intended to be hinged on a vertical axis (6) to the base (1) of a tire removal machine (100), while at its other end it supports a positionable bead release tool (66), the arm being coupled with unilateral engagement to the rod (9) of a pneumatic cylinder-piston unit which is associated with the base, the unilateral engagement being achieved by a plurality of aligned equidistant identical notches (111) provided in the end longitudinal portion of the rod and by a coupling member (18) which is provided on the arm (60) and is arranged to occupy a rest position in which it allows the arm (60) and the rod (9) to slide freely relative to each other, and a working position in which it maintains the arm and rod coupled together. | 1 |
BACKGROUND
The present invention relates to techniques for computer-based classification, which can be used to identify members of groups of interest within datasets.
Classification and pattern recognition techniques have wide-reaching applications. For example, a number of life science applications use classification techniques to identify members of groups of interest within clinical datasets. In particular, one important application involves distinguishing the protein signatures of patients with certain type of cancer from the protein signatures of patients who do not. This problem stems from the need in clinical trials to test the efficacy of a drug in curing cancer while the cancer is at an early stage. In order to do so, one needs to be able to identify patients who have cancer at an early stage.
Conventional diagnostic techniques are not sufficient for this application. A popular technique (from an area that has become known as “proteomics”) is to analyze mass spectra, which are produced by a mass spectrometer from serum samples of patients. Depending on the type of cancer, the mass spectra of serum samples can show distinct signatures, which are not immediately visible to the naked eye. Several existing data mining techniques are presently used to distinguish the cancer spectra from the normal ones, such as Naïve Bayes, Decision Trees, Principle-Components-Analysis based techniques, Neural Networks, etc.
However, these existing techniques are characterized by false-alarm and missed-alarm probabilities that are not sufficiently small. This is a problem because false alarms can cause patients to experience anxiety, and can cause them submit to unnecessary biopsies or other procedures, while missed alarms can result in progression of an undetected disease.
Support Vector Machines (SVMs) provide a new approach to pattern classification problems. SVM-based techniques are particularly attractive for the cancer classification problem because SVM-based techniques operate robustly for high-dimensional feature data, unlike other techniques which have resource requirements that are closely coupled with feature dimensions.
However, the application of SVM's in areas involving huge datasets, such as in proteomics, is constrained by extremely high computation cost, in terms of both the compute cycles needed as well as enormous physical memory requirements.
For example, a quadratic optimization problem arises during the training phase of the SVM's for large datasets, which are common in most life sciences problems. Such a quadratic optimization problem typically requires the memory to accommodate an N×N matrix, where N is the number of data vectors. This creates huge challenges for conventional high-end enterprise computer servers when the input datasets contain thousands or tens of thousands of data vectors. In addition, the training time for the algorithm grows in a manner that is polynomial in N. Current state-of-the-art research papers propose using heuristic, data-level decomposition approaches; but often these heuristic approaches are designed with little or no quantitative justification and suboptimal results.
SUMMARY
One embodiment of the present invention provides a system that performs parallel grouping decomposition to facilitate expedited training of a support vector machine (SVM). During operation, the system receives a training dataset comprised of data vectors. The system then determines whether any data vector in the dataset violates conditions associated with a current SVM. Next, the system divides the violating data vectors into a number of subsets, thereby allowing parallel SVM training for each subset. The system subsequently builds an independent SVM for each subset in parallel based on the current SVM. The system then constructs a new SVM to replace the current SVM based on the SVMs built for each subset of violating data vectors.
In a variation of this embodiment, if any data vector in the dataset violates conditions associated with the new SVM, the system iteratively performs the following operations until no data vector violates conditions associated with the SVM. The system first determines whether any data vector violates conditions associated with the current SVM. The system then divides the violating data vectors into subsets. Next, the system builds an independent SVM for each subset in parallel based on the current SVM. The system subsequently constructs a new SVM to replace the current SVM based on the SVMs built for each subset.
In a variation of this embodiment, the initial SVM contains either no support vectors, or a set of existing support vectors obtained based on prior knowledge of the dataset.
In a variation of this embodiment, building the independent SVM for each subset involves adding the support vectors for the current SVM to the subset, so that each subset contains violating data vectors and all the support vectors for the current SVM.
In a variation of this embodiment, building the independent SVM for each subset in parallel involves solving quadratic optimization problems for each subset in parallel, thereby reducing the total processing time.
In a variation of this embodiment, constructing the new SVM involves collecting support vectors for each SVM built for the subsets, removing duplicates from the collected support vectors, and forming the new SVM based on the collected support vectors.
In a variation of this embodiment, determining whether any vector in the dataset violates conditions associated with the SVM involves evaluating whether each data vector violates a set of Karush-Kuhn-Tucker (KKT) conditions for the current SVM.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 illustrates a multiprocessor system in accordance with an embodiment of the present invention.
FIG. 2 illustrates the process of dividing violating data vectors into subsets in accordance with an embodiment of the present invention.
FIG. 3 illustrates presents a flow chart illustrating the process of parallel grouping decomposition in accordance with an embodiment of the present invention.
FIG. 4 illustrates a set of exemplary data vectors and a separating hyperplane in accordance with an embodiment of the present invention.
DETAILED DESCRIPTION
The following description is presented to enable any person skilled in the art to make and use the invention, and is provided in the context of a particular application and its requirements. Various modifications to the disclosed embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments and applications without departing from the spirit and scope of the present invention. Thus, the present invention is not limited to the embodiments shown, but is to be accorded the widest scope consistent with the principles and features disclosed herein.
The data structure and code described in this detailed description are typically stored on a computer readable storage medium, which may be any device of medium that can store code and/or data for use by a computer system. This includes, but is not limited to, magnetic and optical storage devices, such as disk drives, magnetic tape, CDs (compact discs) and DVDs (digital versatile discs or digital video discs).
Multiprocessor System
FIG. 1 illustrates an exemplary multiprocessor system 100 in accordance with an embodiment of the present invention. Multiprocessor system 100 is a shared-memory multiprocessor system, which includes a number of processors 151 - 154 coupled to level one (L1) caches 161 - 164 which share a level two (L2) cache 180 and a memory 183 . Memory 183 contains SVM code that performs parallel grouping decomposition for fast training of large scale SVMs. This parallel grouping decomposition process is described in more detail below.
During operation, if a processor 151 accesses a data item that is not present in local L1 cache 161 , the system attempts to retrieve the data item from L2 cache 180 . If the data item is not present in L2 cache 180 , the system first retrieves the data item from memory 183 into L2 cache 180 , and then from L2 cache 180 into L1 cache 161 .
Multiprocessor system 100 also supports a coherency protocol that operates across bus 170 . This coherency protocol ensures that if one copy of a data item is modified in L1 cache 161 , other copies of the same data item in L1 caches 162 - 164 , in L2 cache 180 and in memory 183 are updated or invalidated to reflect the modification.
Although the present invention is described in the context of the shared-memory multiprocessor system 100 , the present invention is not meant to be limited to such a system. In general, the present invention can operate in any computer system or distributed system which contains multiple processors. For example, the present invention can operate in a distributed computing system in which separate computing systems are coupled together through a network. Hence, the term “multiprocessor system,” as used in this specification and the appended claims, refers to any computer system or distributed system containing multiple processors which can work together on a given computational task.
Support Vector Machine
One embodiment of the present invention provides unique advantages which enable training of large scale SVMs in reasonable time using limited resources and. This procedure reformulates the SVM training problem into a quadratic optimization problem (QP) with specific constraints on the variables. In this way, standard numerical solvers can be used to solve SVM training problems. The rest of this section explains the process of formulating an SVM training problem into a quadratic problem.
First, let X i denote an m-dimensional vector, i.e., X i εR m . Vector X i represents a data point in a data set, such as a snapshot of the physical telemetry signals of a computer server or a protein mass spectrum obtained from a mass spectrometer. In addition, let D denote a data set of n such data points:
D={X i ,Y i }, i=1, . . . , n
where Y i ε{−1,+1} represents the presence (+1) or absence (−1) of the property or feature of interest for point X i . Data set D is generally called a training data set, because it is used to build an SVM.
For example, X i can be a sample of a blood mass spectrum. Each element of a vector data point represents an amplitude at a certain m/z value. A nonzero amplitude means that there is a peptide or a peptide fragment with such mass in the blood sample. Y i represents the absence (−1) or presence (+1) of cancer in the patient. The goal is to build a classifier that uses X as an input and then correctly classifies the patient as having cancer or not having cancer.
To build an SVM for classification, the training data set D ideally includes examples from patients with and without cancer. Then, the classifier learns a differentiating feature in the data set which separates data points associated with cancer patients from those associated with non-cancer patients.
Given a training set D, an SVM is built by solving the following prime quadratic problem (QP 0 ):
(QP 0 ): min ∥W∥ 2 , subject to the following constraints:
{ ( Φ ( X i ) · W ) + b ) ≥ 1 - ξ i for Y i = + 1 ( Φ ( X i ) · W ) + b ) ≤ - 1 + ξ i for Y i = - 1 ξ i ≥ 0 , ∀ i
where Φ is a mapping function from R m space to some Euclidean space H called feature space:
Φ: R m →H.
Wherein WεH is a vector normal to the hyperplane that separates the points representing the two classes, b is an unknown scalar, and ξ i is a set of positive slack variables representing the penalty of incorrect classification. The solution to the problem above defines an optimal separating hyperplane.
It is more convenient to solve a Lagrangian formulation of this problem:
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{ 0 ≤ a i ≤ C , i = 1 , … , n ∑ i a i Y i = 0
where a i is a set of Lagrange multipliers corresponding to the inequality constraints in the prime problem QP 0 . Constant C represents the amount of penalty for incorrect classification, and K(·,·) is a kernel function. Examples of kernel functions include K(x,y)=x·y, K(x,y)=(x·y+1) p , K(x,y)=tan h(kx·y−δ).
The optimal solution of problem QP 1 , denoted as a i *, ideally satisfies the following conditions, namely the Karush-Kuhn-Tucker (KKT) conditions, of the prime problem QP 0 :
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Data points X i for which there is a corresponding 0<a i <C are called support vectors and are denoted as S X i . Only support vectors are used for computing the separating hyperplane or for making a classification decision. All other data points can be removed from the training data set with no impact on the classification results.
The dimension of QP 1 is n, which is the number of data points in the training set. When n is large (e.g., n=1,000 or more), the classical sequential QP solvers become very slow and sometimes cannot find a solution at all. To overcome this problem, one embodiment of the present invention provides an approach for parallel processing of the quadratic problem QP 1 , the solution of which produces the desired SVM.
Parallel Grouping Decomposition
One embodiment of the present invention uses a new technique called parallel grouping decomposition to perform SVM training in parallel. This approach allows solving arbitrarily large SVM problems using parallel processing. During operation, the system iteratively performs parallel grouping decomposition until a correct SVM is obtained. At the beginning of an iteration, the system first forms an initial support vector pool, S={ S X i , S Y i , i=1, . . . , S n}, based on prior knowledge about the problem, or based on the results from previous training procedures. (For example, the initial pool can be an empty set for a new problem.) Note that this pool serves as a starting point for adjusting the SVM to incorporate new information. When the training process is complete, this pool ideally contains the correct support vectors for the problem and the system accordingly exits the iteration.
Next, the system checks the KKT conditions for the prime quadratic problem QP 0 to determine if the current support vector pool S is the solution for the problem. If the KKT conditions are satisfied for each a i , then the original QP 0 has been solved and the current pool S contains the correct support vectors for the solution SVM. Otherwise, the system finds all a i 's which violate the KKT conditions and forms a separate data set V D of violating vectors:
V D ={ V X i , V Y i },i=1, . . . , V N
where V N is the total number of violators.
Note that the check of KKT conditions ideally is performed for all data vectors, because some of the vectors that violate the KKT conditions during a previous iteration may not be violators during the current iteration. Similarly, some of the data vectors that do not violate the KKT conditions during a previous iteration may violate the KKT conditions during the current iteration.
The system then divides the data set V D into G groups (subsets) denoted as V D g , where g=1, . . . , G. The system may do so randomly, so that there can be approximately equal proportions of positive and negative examples in each group. The number of groups, G, can be specified as an adjustable parameter. Alternatively, the size of each group can be specified and G is computed as G=[ V N/Group_Size].
The system subsequently adds to each subset V D g the current support vectors, so that each subset contains a portion of KKT-violating data vectors and all of the support vectors contained in S:
V D g ={ V X i g , V Y i g , S X j , S Y j } i=1, . . . , V N g , j=1, . . . , S n.
The system then builds G independent SVMs for each subset in parallel. The system may use any available quadratic solver to solve these smaller quadratic problems. Because these quadratic problems are independent, all the necessary computations can be performed in parallel very efficiently.
After obtaining G SVMs for the G subsets, the system collects the support vectors from each of these SVMs and forms a new support vector pool S using these support vectors. Furthermore, the system removes any duplicate support vectors from the support vector pool S. The system then goes back to the beginning of the iteration to determine whether the SVM based on the current S is the correct solution. If so, the system exits. Otherwise, the system repeats the parallel-grouping decomposition again.
Typically, the number of data vector that violate the KKT conditions decreases with each iteration, although this may not always be the case. For practical purposes, the number of violators drops significantly with each iteration and only a few iterations are required to reach the final solution of the original problem. In essence, the parallel grouping decomposition approach divides large data sets into smaller, manageable subsets and finds the exact solution of the original QP problem iteratively while processing all subsets in parallel.
FIG. 2 illustrates the process of dividing violating data vectors into subsets in accordance with an embodiment of the present invention. In this example, a set of violating data vectors 201 is divided into two subsets, namely subset 204 and subset 206 . Each subset contains approximately equal number of positive and negative examples (represented by grey squares and blank squares, respectively). The system then adds to each subset the current support vector pool. The current support vectors are represented in grey circles (positive examples) and blank circles (negative examples).
The system then builds an SVM for each subset, and collects the support vectors corresponding to each subset to form a new support vector pool. Next, the systembuilds a new SVM 208 based on the new support vectors. The system subsequently determines whether all the data vectors satisfy the KKT conditions for the problem. If so, the SVM training is complete and the system exits. Otherwise, the system repeats the parallel grouping decomposition process until it finds a correct SVM.
FIG. 3 illustrates presents a flow chart illustrating the process of parallel grouping decomposition in accordance with an embodiment of the present invention. During operation, the system starts by receiving a data set (step 302 ). The system then determines whether all data vectors satisfy KKT conditions for the current SVM (step 304 ). If so, the problem is solved and the system exits. Otherwise, the system divides the violating data vectors into a number of subsets (step 306 ). In addition, the system adds to each subset the current pool of support vectors (step 308 ).
Next, the system builds an independent SVM for each subset in parallel (step 310 ). After obtaining SVMs for the subsets, the system collects the support vectors from each subset and removes the duplicates (step 312 ). The system subsequently constructs a new SVM using the collected support vectors (step 314 ). The system then determines again whether all the data vectors satisfy the KKT conditions for the current SVM (step 304 ).
FIG. 4 illustrates a set of exemplary data vectors and a separating hyperplane in accordance with an embodiment of the present invention. In this example, the objective is to find an optimal separation of one set of observations (represented by dark squares) from another set of observations (represented by grey circles). As can be observed in FIG. 4 , this is a challenging problem because there is a “double horseshoe” relationship between the two sets of observations. It is obvious that naïve approaches which produce a linear line or linear plane to separate these two classes will result in numerous misidentifications.
Using the present parallel grouping decomposition approach, a system can easily solve this problem. In one exemplary experiment, the original data set is partitioned into 24 groups during the first iteration. After the first iteration, only a few vectors violate the KKT conditions. Therefore, the second iteration includes only one grup of violators combined with the support vectors obtained during the first iteration. After the second iteration, all the data vectors satisfy the KKT conditions and the original problem is solved in a total of 0.13 time units. By contrast, the same problem is solved by a state-of-art conventional SVM training system in a total of 0.51 time units.
The foregoing descriptions of embodiments of the present invention have been presented only for purposes of illustration and description. They are not intended to be exhaustive or to limit the present invention to the forms disclosed. Accordingly, many modifications and variations will be apparent to practitioners skilled in the art. Additionally, the above disclosure is not intended to limit the present invention. The scope of the present invention is defined by the appended claims. | One embodiment of the present invention provides a system that performs parallel grouping decomposition to facilitate expedited training of a support vector machine (SVM). During operation, the system receives a training dataset comprised of data vectors. The system then determines whether any data vector in the dataset violates conditions associated with a current SVM. Next, the system divides the violating data vectors into a number of subsets, thereby allowing parallel SVM training for each subset. The system subsequently builds an independent SVM for each subset in parallel based on the current SVM. The system then constructs a new SVM to replace the current SVM based on the SVMs built for each subset of violating data vectors. | 8 |
This is a continuation of application Ser. No. 08/558,381, filed on Nov. 16, 1995 now abandoned, which was abandoned upon the filing hereof which is a continuation of 08/216,843 filed on Mar. 24, 1994 now abandoned, which is a divisional of 08/051,396 filed Apr. 23, 1993 now abandoned.
FIELD OF THE INVENTION
This invention relates to a process and apparatus for treating cellulosic material such as wood chips for pulp making and, more specifically, for reducing or eliminating the use of environmentally undesireable chemicals in such a process.
BACKGROUND OF THE INVENTION
The environmental authorities are placing ever more stringent demands on the pulp industry to decrease the use of chemicals which can be damaging to the environment, such as, for example, chlorine. Thus, permitted discharges of organic chlorine compounds in the waste water from bleaching plants, following on from the cooking process, have been decreased progressively and are now at such a low level that pulp factories have in many cases stopped using organic chlorine compounds as bleaching agents. In addition, market forces are tending progressively to increase the demand for paper products which are not bleached with chlorine.
The pulp industry is therefore searching for methods which allow bleaching of pulp without using these chemicals. The lignox method (see SE-A 8902058), in which, inter alia, bleaching is carried out with hydrogen peroxide, may be mentioned as an example of such a method. Ozone is another interesting bleaching chemical which is also gaining increased application. It is thus possible, using bleaching chemicals of this nature, to achieve those brightnesses which are required for marketable pulp, i.e. 89 ISO and greater, without using chlorine-containing bleaching agents.
There is, however, a problem in using presently known bleaching procedures with these bleaching chemicals which do not contain chlorine, namely that they have a relatively large effect in diminishing the quality of the pulp fibres.
SUMMARY OF THE INVENTION
By means of experiments which have been conducted under the auspices of Kamyr AB, it has been found, surprisingly, that extremely good results, with regard to delignification and strength properties, can be obtained if the pulp is cooked at the same temperature level in substantially the whole of the digester, i.e., if essentially the same temperature is maintained in all cooking zones, and if a certain quantity of alkali is also supplied to the lowest zone in the digester, which zone is normally used for counter-current washing. Owing to the fact that essentially the same temperature level is maintained in virtually the whole of the digester, very extensive delignification can be achieved at a relatively lower temperature than used previously. In addition, it has been found that the strength properties are affected in a particularly favourable manner, that a higher yield of the crude fibre product is obtained and that the quantity of reject material decreases.
The invention relates to an advantageous arrangement of screens in the digester and feed conduits for achieving a cooking according to the new process, in particular with regard to digesters built according to an older principle and consisting of an upper concurrent cooking zone and a lower counter-current washing zone. Such an arrangement is necessary since certain practical problems arise as a consequence of an isothermal cooking process. The first such problem is the difficulty of efficiently reaching and maintaining the temperature in the lower part of the digester, i.e. that part which is normally employed for washing.
This problem is solved by creating a more efficient circulation and thus temperature distribution in the lower part (the high-heat or washing zone) of the digester. In this context it has been found to be advantageous to use digester screening arrangements consisting of circular screens, in particular so-called , man hole screens where a relatively large circular opening in the digester wall is provided with a circular screen plate that is typically sealed and bolted to the periphery of the opening. With an appropritate distribution of such screen holes, the process is advantageous especially in connection with converting existing digesters, both of the modified type and the older type, for operation according to the new process.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A, 1B and 1C a comparison is made in the three diagrams between isothermal cooking and so-called modified conventional cooking (MCC).
FIG. 2 shows a diagram which describes degree of delignification and viscosity (the viscosity is normally regarded as indicating the strength properties of the pulp).
FIG. 3 shows how, in a preferred manner, an existing digester can be converted, using manhole screens, to be operated according to the novel process and
FIG. 4 shows a specific type of man hole screens with a portion broken away to reveal a portion of a screen.
DETAILED DESCRIPTION
The advantages of the present invention are most clearly apparent from the diagrams shown in the FIG. 1A, 1B and 1C which show comparative values between pulp (softwood) which has been cooked using a conventional, modified cooking technique and pulp which has been cooked using the process according to the invention, (in a similar digester, i.e. with a concurrent upper cooking zone, a central counter-current cooking zone and a bottom counter-current washing zone) in which a constant temperature level of about +155° C. has been maintained in the whole digester.
The three diagrams of FIG. 1A, 1B and 1C compare different results obtained with isothermal cooking and modified conventional cooking (MCC). These surprisingly positive results show, according to FIG. 1A, that, with a given amount of added alkali, substantially lower kappa numbers are obtained using isothermal cooking. Furthermore, the second FIG. 1B shows that manifestly improved strength properties are obtained when cooking down to the same kappa number. In addition, the third FIG. 1C shows that there is also the advantage that the quantity or reject wood (shives) decreases. If the fact is also taken into account that overall substantial energy savings are made when the temperature level is kept constant as well as lower than previous temperatures, it is evident that the results may be regarded as being surprisingly positive. FIG. 2 additionally demonstrates that, using the method according to the invention, very low kappa numbers are reached while at the same time retaining good pulp strength (viscosity of about 1000) after oxygen delignification. Thus, when employing the method according to the invention, so-called environmentally friendly bleaching chemicals, such as peroxide and ozone, can be employed in subsequent bleaching stages without risking too low a strength for bleaching up to the level of brightness, and therewith also the level of purity, which the market demands.
FIG. 3 shows the lower part of a digester 1, which is 4 intended to represent an existing digester shell, such as disclosed in commonly owned U.S. Pat. No. 3,802,956 (the disclosure of which is incorporated herein by reference) on which has been arranged a new digester screening arrangement 2 in order to be able to raise the temperature in the counter-current zone. The digester is of the type which may have an upper impregnation zone (not shown) and next has an upper concurrent part and a lower counter-current part. In the past, in such a digester, full cooking temperature is normally maintained in the a concurrent zone (i.e. about 162° C. for hardwood and about 168° C. for softwood) while in the countercurrent part, which in the main is a washing zone, the temperature is about 135° C. on a level pith the lower screen.
According to the present Invention, the counter-current zone of the digester which has been fitted with a further screening arrangement will be referred to as a cooking zone, even if it is to be considered as a washing zone according to conventional operation.
The new digester screening arrangement 2 consists of a number of so-called manhole screens 2A for withdrawal 3 of cooking liquid in the lower part of the digester and is arranged immediately above the lower screening arrangement 1B of conventional structure, preferably at most 1.5 meters above and more preferably at most 1 meter above, measured from the upper edge of the lower digester screening arrangement 1B to the lower edge of the newly fitted digester screening arrangement 2A. Wash liquor is supplied to the lower part of the digester through an inflow conduit arrangement 4 attached in the vicinity of the bottom 1A of the digester and cooking liquid (with alkali addition) through the central pipes 5A, 5B. The cooked pulp is taken out from the bottom of the digester via a conduit 1E. Valves 8 and 9, respectively, control introduction of white digesting liquor through pipes 1F and 1G into the circuits for pipes 5B and SA upstream of the respective heat exchangers 6A and 6B to assist in maintaining the necessary control of the heat content of the liquors introduced as described.
One of these central pipes, 5A, which belongs to the original system of the digester, penetrates down to the lower screening arrangement 1B of the digester, after which a portion of the liquid is drawn off through screen 1B and passed to the heat exchanger 6A. After heating via the first heat exchanger 6A, the liquid is passed back through pipe 5A on a level with the digester screening arrangement 1B to maintain the desired isothermal temperature condition at this zone of the digester. Subsequently, a part of the liquid flows in a countercurrent direction upwards towards the newly fitted digester screening arrangement 2 comprising the screens 2A. The liquid withdrawn from this system of screens 2A passes through the conduit arrangement 3 and is heated via a heat exchanger 6B to the desired temperature before it discharges, via a second, central pipe 5B, provided according to the present invention, immediately above the newly fitted digester screening arrangement 2, as shown. A part of the cooking liquid supplied in this manner through pipe SB, which liquid has thus achieved the desired temperature, chemical strength and distribution over the whole of the cross-section of the digester, continues to flow upwards in the digester toward the originally installed screen arrangement 1D. In the central digester screening arrangement 1D, the spent cooking liquid, together with undissolved wood material, is drawn off for further treatment. Above the screen arrangement 1D, may be provided a level control device such as a strainer 1H of conventional construction.
The surface of each screening element 2A is made relatively small, preferably less than 0.3 m 2 . An advantage of screening elements of small area is that efficient back flushing can be achieved, which is often of great importance if the circulation flow is to function efficiently. The new screening arrangement 2 is preferably fitted with ring duct or pipes 2C from which an individual conduit goes to each and every one of the screening elements 2A. Using such a construction, and a valve arrangement in the associated conduits for each element 2A, a limited number (for example 4) of screening units 2A can be efficiently backflushed at a time. In FIG. 4, two adjacent screen elements are shown. A plurality of these will be evenly spaced about the circumference of the vessel 1 and each has an outer wall 20 which serves as the screen plug means. In screen element 22, the wall 20 is broken away to show the underlying screen 24 itself. A valve 26 is placed in the conduit 28 connected through the outer wall 22. Owing to the relatively small total screening surface which is back-flushed under these circumstances (for example 1 m 2 ), a very efficient backflushing which cleans the screens is obtained, thereby ensuring that the circulation is highly efficient.
It will be apparent that very close control of the temperature of contents of the digester in the counter current zone and the extended phase zone beneath the new screen arrangement 2 can be achieved by the provided apparatus to assure substantially isothermal conditions in the concurrent, counter-current and extended phase, formerly washing, zones.
The invention is not limited by that which has been described above, but can be varied within the scope of the subsequent patent claims. Thus, an existing digester of the modified continous cooking type can also be arranged in accordance with the invention, where, therefore, the digester has an upper concurrent part, a central, mainly countercurrent part and a lower counter-current part, where addition of a part of the cocking liquid takes place in the said lower counter-current part, the so-called high heat zone. A digester of the so-called hydraulic type, with a lower temperature in the upper part (the impregnation zone), may also advantageously be fitted with a digester screening arrangement according to the invention for cooking according to the invention, that is, isothermally. Additionally the method may be used in connection with all types of cooking liquid, even if the method is principally intended for producing sulphate pulp. In addition, it is obvious to the person skilled in the art that the invention is not limited to the abovementioned exemplifying temperature levels. In this connection, however, it is important that the average temperature level in the digester preferably exceeds +150° C. but is lower than +165° C., and preferably is between 150-155° C. for hardwood and between 160-165° C. for softwood, and furthermore that the average temperature in the cooking zone/zones is preferably about +151° C.±1° C., when the wood is hardwood, and that the average temperature in a digester is +159° C.±1° C., when the wood is softwood. In addition, it is understood that screens deviating from a purely circular form, for example oval screens, may also be used, whereby, for technical reasons related to the construction, the smallest radius of curvature should not fall below 0.2 m. Finally, it is pointed out that new digesters can readily also be fitted with screening arrangements, and be operated, according to the invention. | The present invention relates to a digester for continuous cooking under raised pressure and temperature of fibre material in a vertical digester (1), where input of fibre material and cooking liquid takes place at the top of the digester, withdrawal of spent cooking liquor is carried out from at least one digester screening arrangement (1D) between the top and the bottom of the digester, and fibre material is fed out from the bottom (1C) of the digester, wherein the digester (1) is fitted with an additional digester screening arrangement (2) above the lowest screening arrangement (1B) of the digester so that the temperature in all the participatory cooking zones in the digester can be kept at essentially the same temperature level. | 3 |
FIELD OF THE INVENTION
[0001] The present invention relates to apparatus and methods for the operation of passive light emitting diode (LED) lighting equipment, and in particular to such apparatus and methods as may avoid the need to use electrolytic capacitors.
BACKGROUND OF THE INVENTION
[0002] LED technology has been promoted as a promising lighting technology to replace energy-inefficient incandescent lamps and mercury-based linear and compact fluorescent lamps. It is often claimed by LED manufacturers that the LED devices have a long lifetime that could be higher than 5 years. However, the electrolytic capacitors used in the power circuit and the electronic controls for LED systems have a limited lifetime, typically 15000 hours (or 1.7 years) at an operating temperature of 105° C. The lifetime of an electrolytic capacitor is highly sensitive to the operating temperature. The lifetime is doubled if the operating temperature is decreased by 10° C. and halved if increased by 10° C. Therefore, the short lifetime of electronic control circuits (sometimes known as ballasts) for LEDs remains one major bottleneck in the utilization of LED technology.
[0003] In general, electrolytic capacitors are used in power inverter circuits and electronic control circuits for lighting systems because they provide the necessary large capacitance of the order of hundreds and even thousands of micro-Farads, while other more long-lasting capacitors such as ceramic, polypropylene and metallized plastic film capacitors have relatively less capacitance of several tens of micro-Farads or less. The large capacitance of electrolytic capacitors is usually needed to provide a stable DC link voltage for the ballast circuit to provide stable power (with reduced power variation) for the load; a stable DC power supply in the electronic control for the power inverter circuit.
[0004] FIG. 1 shows the schematic of a typical off-line lighting system. An off-line system here means a system that can be powered by the ac mains. The power conversion circuit can adopt a two-stage approach in which an AC-DC power stage with power factor correction is used as the first power stage, which is followed by a second DC-DC power conversion stage for controlling the current for LED load. An alternative to the two-stage approach is to employ a single-stage approach which combines the two power stages into one and such a technique has been reported in many off-line power supply designs. In both approaches, electrolytic capacitors are used to provide the energy storage and buffer so that the difference between the input power and the output power consumed by the load can be stored or delivered by the capacitors.
[0005] Regardless of whether a single-stage or a two-stage approach is used, a large capacitance (requiring the use of electrolytic capacitors) is needed as energy-storage to cater for the difference between the input power from the ac mains and the almost constant power of the LED load. The input power of an off-line lighting system is typically a periodically pulsating function as shown in FIG. 1 . For example, if power factor is close to one, the input voltage and current are in phase and thus the input power follows a pulsating waveform (similar to a rectified sinusoidal waveform). If the lighting load is of constant power, then the capacitors are needed to absorb or deliver the difference in power between the ac mains and the lighting load as shown in FIG. 1 .
[0006] An electronic ballast circuit without the use of electrolytic capacitors has been proposed. But the requirement for active power switches in such proposal means that an electronic control board that provides the switching signals for the active power switches is needed and this electronic control board needs a power supply that requires the use of electrolytic capacitors. In general, electrolytic capacitors are needed in a DC power supply for providing the hold-up time (i.e. to keep the DC voltage for a short period of time when the input power source fails.) Power electronic circuits that use active switches usually need a DC power supply for the gate drive circuits that provide switching signals for the active electronic switches. Therefore, it would be useful if a passive electronic ballast circuit can be developed for providing a stable current source for the LED load. A passive ballast circuit without active switches, electronic control board and electrolytic capacitors would be a highly robust and reliable solution that enhances the lifetime of the entire LED system. The remaining challenge is to determine how to provide a stable current source for the LED load based on a totally passive circuit.
SUMMARY OF THE INVENTION
[0007] According to the present invention there is provided an LED lighting system comprising: (a) a rectification circuit for rectifying an AC input power and generating a rectified DC power, (b) a first circuit electrically coupled to the rectification circuit for reducing the voltage ripple of said rectified DC power, (c) a second circuit electrically coupled to the first circuit for generating a current source from the voltage ripple reduced rectified DC power, and (d) at least one LED electrically coupled to the second circuit and receiving said current source as an input.
[0008] Preferably the first circuit is a valley-fill circuit located between the rectification circuit and the second circuit. The valley-fill circuit may include a voltage-doubler.
[0009] Preferably the second circuit comprises an inductor. The second circuit may further function as a current ripple reduction circuit. Such a current ripple reduction circuit may comprise a coupled inductor with a capacitor.
[0010] In preferred embodiments of the invention the power supplied to the at least one LED is permitted to vary, and at least one operating and/or design parameter of the at least one LED is chosen such that a variation in luminous flux resulting from the varying power is not observable to the human eye.
[0011] Viewed from another broad aspect the present invention provides a method of operating a LED lighting system comprising: (a) rectifying an AC input voltage to generate a rectified DC power, (b) reducing a voltage ripple of the rectified DC power, (c) generating a current source from the voltage ripple reduced rectified DC power, and (d) providing the current source as an input to at least one LED, wherein the power supplied to the at least one LED is permitted to vary, and wherein at least one operating and/or design parameter of the at least one LED is chosen such that a variation in luminous flux resulting from the varying power is not observable to the human eye.
[0012] Preferably a thermal characteristic of the at least one LED may be chosen such that the variation in luminous flux resulting from the varying power is not observable to the human eye. Such a thermal characteristic may comprise a design of a heatsink for the at least one LED and/or the provision of forced cooling or natural cooling.
[0013] Preferably a valley-fill circuit is used to reduce the voltage ripple of the rectified DC power. The valley-fill circuit may comprise a voltage-doubler.
[0014] In preferred embodiments of the invention the method further comprises reducing the current ripple of the current source. A coupled inductor with a capacitor may be used to reduce the current ripple.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] Some embodiments of the invention will now be described by way of example and with reference to the accompanying drawings, in which:
[0016] FIG. 1 shows a schematic and power profiles of a typical off-line LED lighting system according to the prior art;
[0017] FIG. 2 shows a schematic and “modified” power profiles of an off-line LED lighting system according to an embodiment of the invention;
[0018] FIGS. 3( a )-( c ) show the variation of LED power and luminous flux in an embodiment of the present invention;
[0019] FIGS. 4( a ), ( b ) and ( c ) show ( a ) a schematic diagram of a passive off-line circuit design for an LED system using an inductor for current ripple reduction, and ( b ) and ( c ) using a coupled inductor for current ripple reduction;
[0020] FIG. 5 shows a schematic of an example of one possible hardware implementation of the proposed passive circuit for an off-line LED system using a standard valley-fill circuit;
[0021] FIG. 6 shows a model used for simulation of the circuit in FIG. 5 ;
[0022] FIG. 7 shows an example of a proposed passive circuit with a standard valley-fill circuit for multiple loads;
[0023] FIG. 8 shows an example of a proposed passive circuit using a valley-fill circuit with a voltage doubler for multiple loads;
[0024] FIG. 9 shows an LED system according to an embodiment of the invention under a simulation evaluation (L=1H);
[0025] FIGS. 10( a ) and ( b ) show ( a ) simulated input voltage and current of the system of FIG. 9 , and ( b ) simulated input power of the system of FIG. 9 ;
[0026] FIGS. 11( a )-( d ) show ( a ) simulated voltage and current of the LED module for the circuit of FIG. 9 , ( b ) simulated total power for the LED module and for individual LEDs in the module for the system in FIGS. 9 , ( c ) and ( d ) two examples of the relationship between a variation of LED power and luminous flux fluctuation for a LED system using 3 W LED devices;
[0027] FIG. 12 shows an LED system according to an embodiment of the invention under a simulation evaluation (L=2H);
[0028] FIGS. 13( a )-( d ) show ( a ) simulated input voltage and current of the system of FIG. 12 , ( b ) simulated input power of the system of FIGS. 12 , ( c ) and ( d ) two examples of the relationship between a variation of LED power and luminous flux fluctuation for a LED system using 3 W LED devices;
[0029] FIG. 14 shows an embodiment of a LED system with “coupled inductor” of L=2H under simulation evaluation (L=2H);
[0030] FIGS. 15( a )-( d ) show ( a ) simulated input voltage and current of the system of FIG. 14 , ( b ) simulated input power of the system of FIGS. 14 , ( c ) and ( d ) two examples of the relationship between a variation of LED power and luminous flux fluctuation for a LED system using 3 W LED devices;
[0031] FIG. 16 shows a diode-clamp that may be added to each LED string in embodiments of the invention; and
[0032] FIGS. 17( a ) and ( b ) illustrate the use of the valley-fill circuit in reducing the voltage ripple.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0033] One important aspect of this invention at least in its preferred forms is to provide a way to reduce the size of the capacitors that is needed so that capacitors other than the electrolytic type can be used. With electrolytic capacitors eliminated in the lighting system, the whole system can be more reliable and last longer.
[0034] FIG. 2 is a modified version of FIG. 1 and is used to illustrate this aspect of the invention. If the LED load power is allowed to fluctuate to some extent, the amount of energy buffer required in the energy-storage element of the system becomes less and therefore the size of the capacitance can be reduced to a level that other non-electrolytic capacitors can be used to replace the electrolytic capacitor. Furthermore as the circuit contains only passive components rather than active components complicated control circuitry (which may also require electrolytic capacitors) can be avoided.
[0035] In addition to the elimination of electrolytic capacitors, the design is also concerned with the input power factor because there is an international standard IEC-61000 governing the input power factor. Passive power correction circuits such as valley-fill circuits and their variants (K. Kit Sum, “Improved Valley-Fill Passive Current Shaper,” Power System World 1997, p. 1-8; Lam, J.; Praveen, K.; “A New Passive Valley Fill Dimming Electronic Ballast with Extended Line Current Conduction Angle,” INTELEC '06. 28th Annual International Telecommunications Energy Conference, 2006. 10-14 Sep. 2006 Page(s): 1-7), incorporated herein by reference, can be used in the passive ballast circuit in embodiments of this invention.
[0036] Valley-fill circuits allow the input current to be smoothed so that the current distortion factor and thus the input power factor can be improved. The choice of the capacitors used in the valley-fill circuit can be made so that non-electrolytic capacitors can be used. Unlike previous applications, the valley-fill circuit is used in embodiments of this invention to reduce the output voltage ripple which in turn will reduce the current ripple in the later power stage. This aspect of the valley-fill circuit application has not been reported previously because in the prior art valley-fill circuits were primarily used for voltage source applications and were used as a means for input power factor correction with their outputs are nominally connected directly to another power converter or a load. For example, in the National Semiconductor Note: LM3445 Triac Dimmable Offline LED Driver March 2009, incorporated herein by reference, the two capacitors C7 and C9 in the valley-fill circuit are electrolytic capacitors and the valley-fill circuit provides a “voltage source” to a buck converter which in turn controls the power of the LED load. Such example of valley-fill circuit application highlights the traditional use of “electrolytic capacitor” in absorbing large power variation and the voltage source nature of prior art.
[0037] In contrast in embodiments of the present invention valley-fill circuits are used to reduce the input voltage ripple. As shown in FIG. 17( a ), the output voltage of the diode rectifier has high voltage ripple. However, the output voltage of the valley-fill circuit is significantly reduced as shown in FIG. 17( b ). In embodiments of this invention, the valley-fill circuit is not connected directly to the load or another power converter as in prior art, but is connected directly to an inductor or a coupled-inductor based current ripple cancellation circuit for providing a smooth current to the LED load.
[0038] In embodiments of the invention an inductor ( FIG. 4( a )) or a coupled inductor with ripple cancellation ( FIG. 4( b )) may be used to limit the output current ripple and hence the power variation for the LED load.
[0039] FIG. 4( a ) and FIG. 4( b ) show schematic diagrams of passive circuits according to embodiments of the invention that can provide high reliability, long lifetime and low cost. Each system consists of a diode rectifier, a valley-fill circuit for improving the input power factor, an inductor for turning the voltage source into a current source with reduced current ripple ( FIG. 4( a )) and the LED load. An alternative embodiment as shown in FIG. 4( b ) is to replace the inductor in FIG. 4( a ) with a coupled inductor and a capacitor so that these components form a coupled inductor with current ripple cancellation function. It will be shown that such current ripple cancellation which is commonly used in high-frequency (0.20 kHz) switching power supplies can also be effective in low-frequency operation. The LED load could be an LED array or multiple arrays in modular forms. Various valley-fill circuits or their improved versions can be used to improve the input power factor. In embodiments of this invention, non-electrolytic capacitors are used in the valley-fill circuit and current-ripple cancellation circuit. Either a standard valley-fill circuit or a valley-fill circuit with voltage doubler can be used in this invention.
[0040] Considering firstly FIG. 4( a ), let the output voltage of the valley-fill circuit be V out and the overall voltage of the LED module (with LED devices connected in series) be V LED . The inductance of the inductor can be designed to limit the current through the LED module because the current ripple ΔI LED can be expressed as:
[0000]
Δ
I
LED
=
(
V
out
-
V
LED
)
Δ
t
L
[0000] where Δt is the time period during the current change.
[0041] From the above equation, it can be seen that the size of the inductor L can be used to reduce the current ripple, which in turn can limit the change of total LED power because
[0000] ΔP LED =V LED ΔI LED .
[0042] An alternative shown in FIG. 4( b ) is to use a coupled inductor with current ripple cancellation as described in the following (Hamill, D. C.; Krein, P. T.; “A ‘zero’ ripple technique applicable to any DC converter,” 30th Annual IEEE Power Electronics Specialists Conference, 1999. PESC 99. Volume 2, 27 Jun.-1 Jul. 1999 Page(s):1165-1171; Schutten, M. J.; Steigerwald, R. L.; Sabate, J. A.; “Ripple current cancellation circuit” Eighteenth Annual IEEE Applied Power Electronics Conference and Exposition, 2003. APEC '03. Volume 1, 9-13 Feb. 2003 Page(s):464-470; Cheng, D. K. W.; Liu, X. C.; Lee, Y. S.; “A new improved boost converter with ripple free input current using coupled inductors,” Seventh International Conference on Power Electronics and Variable Speed Drives, 1998. (Conf. Publ. No. 456) 21-23 Sep. 1998 Page(s):592-599), incorporated herein by reference. The primary winding of the coupled inductor is used as the DC inductor just as in the embodiment of FIG. 4( a ). The secondary winding is coupled to the primary winding and provides the ac current to reduce the ripple in the load. When the primary current in the first inductor is increasing into the dotted terminal of the primary winding (i.e. changing positively), ac flux caused by the increasing primary current is coupled to the secondary ac winding. The transformer action causes a current to flow out of the dotted terminal of the secondary winding into a capacitor in order to cancel the ac flux. Thus, the overall current ripple in the output of the coupled inductor (including both primary and secondary windings) and the load is reduced. Similarly, when the primary current flowing into the dotted terminal of the primary winding is decreasing (i.e. changing negatively), the ac flux coupled to the secondary winding will cause a current to flow into the dotted terminal of the secondary winding and hence reduce the overall current ripple of the couple inductor. The effect of the coupled inductor on reducing the current ripple is illustrated in FIG. 4( c ).
[0043] In embodiments of the present invention there will be fluctuation of the LED load power, but it is possible to obtain luminous output from the LED system with minimum luminous flux fluctuation even though the LED load power will fluctuate. This can be seen by considering the relationship between the luminous flux φ v and LED power P d as shown in FIGS. 3( a )-( c ). Let us label the maximum power and minimum power of the LED load as Pmax and Pmin, respectively in FIG. 3( a ). It has been shown that the relationship of the luminous flux and the power of a LED system follows an asymmetric parabolic curve as shown in FIG. 3( b ) (Hui S. Y. R. and Qin Y. X., “General photo-electro-thermal theory for light-emitting diodes (LED) systems,” IEEE Applied Power Electronics Conference, February 2009, Washington D.C., USA, paper 16.2; U.S. Ser. No. 12/370,101 the contents of which are incorporated herein by reference). If the LED system is designed such that Pmax and Pmin enclose the peak region of the luminous flux—LED power curve where the slope of the curve is minimum as shown in FIG. 3( b ), a significant variation of LED power (ΔP LED ) will only lead to a relatively small variation in the luminous flux (Δφ v ). An alternative is to design the LED thermal design so that P max and P min fall within a region of the luminous flux—LED power curve where the slope of the curve is relatively small (i.e. near the peak value) as shown in FIG. 3( c ).
[0044] In this way, the control circuit can use non-electrolytic capacitors without causing a large variation in the light output of the LED system. This concept can be implemented in existing electronic ballasts by replacing the electrolytic capacitors with other capacitors of lower values and re-designing the LED system so that the LED power variation falls within the peak luminous flux region in the luminous flux—LED power curve.
[0045] Another aspect of the present invention involves the use of novel passive power circuits that can achieve the advantages proposed above without using active electronic switches. Without using active electronics switches, the proposed circuits do not need an electronic control circuit for the switches and can be much more reliable, long-lasting and have lower costs than their active electronic counterparts.
[0046] FIG. 5 shows a circuit diagram based on a standard valley-fill circuit. In the actual simulation as shown in FIG. 6 , a small number of LED devices are represented by individual diodes and a large number of the LED devices are represented by an equivalent resistor that has the same voltage drop and consumes the same power of that group of LED devices when the rated current flow through these series connected devices. A valley-fill circuit with a voltage doubler as shown in FIG. 7 can also be used if desired. If multiple LED modules are used as shown in FIG. 8 , current-balancing devices can be added to ensure that each LED array module shares the same current.
[0047] In order to illustrate this aspect of the present invention, the passive circuit of FIG. 9 is used to drive a series of 3 W LEDs. In the simulation, three diodes are used while the rest of the diodes are represented as an equivalent resistor as explained previously. FIG. 10( a ) shows the simulated input voltage and current of the entire system. It can be seen that the input current waveform is not a sharp pulse (as would be expected from a diode bridge with an output capacitor) and the power factor has therefore been improved. FIG. 10( b ) shows the input power of the system. FIG. 11( a ) shows the simulated voltage and current of the LED module. The inductor is designed so that the LED rated current of 1A (for the 3 W LED devices) is not exceeded in this example. Despite the pulsating input power, the reduction of the voltage fluctuation due to the use of the valley-fill circuit and the filtering effect of the inductor have smoothed the load current considerably. FIG. 11( b ) shows the total LED power and individual LED power. It can be seen that the power variation is within 1.2 W to 3 W (i.e. 60%) in this example. This simulation study confirms that a passive circuit without electrolytic capacitors and active switches can be designed to provide a current source with controlled current ripple for a LED system with input power factor correction.
[0048] This per-unit result of LED power in FIG. 11 can be interpreted with typical LED systems with different thermal designs. For example, it has been shown that the luminous flux—LED power curves depend on the thermal resistance of the heatsinks. FIG. 11( c ) and FIG. 11( d ) show typical curves for LED systems using two different heatsinks for eight 3 W LEDs. The heatsink used for FIG. 11( c ) is smaller than that for FIG. 11( d ). For the example in FIG. 11( c ), a 60% variation from 1.2 W to 3 W for each device will lead to about 24% of light variation. For the example of FIG. 11( d ), a 60% variation of LED power leads to 30% of light variation.
[0049] However, it is important to note that the choice of inductance of the inductor can control the current ripple and therefore the LED power variation. If the inductance L is increased from 1H to 2H ( FIG. 12 ), the simulated LED voltage and current waveforms are plotted in FIG. 13( a ). The corresponding total LED power and individual LED power are included in FIG. 13( b ).
[0050] It can be seen that, with L increased to 2H, the power variation (from 1.6 W to 2.5 W) is 36%. If the same power variation is applied to the two examples in reference Hui et al (Hui S. Y. R. and Qin Y. X., “General photo-electro-thermal theory for light-emitting diodes (LED) systems,” IEEE Applied Power Electronics Conference, February 2009, Washington D.C., USA, paper 16.2), incorporated herein by reference, FIG. 13( c ) and FIG. 13( d ) show that the variation in the luminous flux is approximately 7% and 12%, respectively. It is envisaged that human eyes are not sensitive to such small changes of luminous flux variation.
[0051] It can be seen that a large inductance can reduce the current ripple and LED power variation. The choice of L depends also on the core loss and copper loss in the inductor. The overall design therefore relies on the thermal design as explained in Hui et al and the choice of L so that the operating range can be restricted to the region of the luminous flux—LED power curve where the slope of the curve is small.
[0052] An effective method to further reduce the current ripple and thus LED power variation and light variation is to replace the inductor in FIG. 9 and FIG. 12 with a current-ripple cancellation means in the form of a coupled inductor and a capacitor as shown in FIG. 14 . FIG. 15( a ) and FIG. 15( b ) show the electrical measurements of the system. It can be seen the variations in the LED current ripple and power have been greatly reduced. The power variation is only within 0.2 W (from 1.9 W to 2.1 W). This 9% power variation will lead to less than 4% of light variation in the two examples as shown in FIG. 15( c ) and FIG. 15( d ).
[0053] It should also be noted that it may be desirable to provide a diode-capacitor clamp that can be added to each LED string to provide a current path for the inductor current in case some of the LED devices fail. An example of such a possibility is shown in FIG. 16 .
[0054] From the above it will be seen that in preferred embodiments of the present invention there is proposed the use of a passive power correction circuit such as the valley-fill circuit to reduce the voltage ripple feeding the inductor (or coupled inductor with a capacitor in the form of current ripple cancellation circuit) and the LED modules in order to (i) reduce the current ripple and thus the power variation in the LEDs and (ii) to improve the input power factor. The allowance of some current and power variation in the LEDs within the region of the luminous flux—LED power curve where the slope of the curve is small will lead to only a small variation of the luminous flux from the LED system. The use of the inductance of the inductor or coupled inductor in the form of a current ripple cancellation circuit to further limit the power variation of the LED system.
[0055] By using a suitable thermal design the power variation range of the LED load can be designed to fall within the region of the luminous flux—LED power curve where the slope is small and the luminous flux is maximum or near maximum.
[0056] As a consequence of the requirement of only small capacitance in the proposed system, electrolytic capacitors can be eliminated from this design. Since the entire circuit consists of passive and robust components (such as power diodes, non-electrolytic capacitors and inductors) only and does not need extra control electronics, it features low-cost, high robustness and reliability.
[0057] While several aspects of the present invention have been described and depicted herein, alternative aspects may be effected by those skilled in the art to accomplish the same objectives. Accordingly, it is intended by the appended claims to cover all such alternative aspects as fall within the true spirit and scope of the invention. | This invention is concerned with the control and design of a LED lighting system that does not need electrolytic capacitors in the entire system and can generate light output with reduced luminous flux fluctuation. The proposal is particularly suitable, but not restricted to, off-line applications in which the lighting system is powered by the ac mains. By eliminating electrolytic capacitors which have a limited lifetime of typically 15000 hours, the proposed system can be developed with passive and robust electrical components such as inductor and diode circuits, and it features long lifetime, low maintenance cost, robustness against extreme temperature variations and good power factor. No extra electronic control board is needed for the proposed passive circuits, which can become dimmable systems if the ac input voltage can be adjusted by external means. | 8 |
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] This application claims priority to U.S. Provisional Application No. 61/321,831, filed Apr. 7, 2010. The contents of this priority document and all other references disclosed herein are incorporated in their entirety for all purposes.
BACKGROUND OF THE INVENTION
[0002] Wetting properties of materials have interested researchers for decades, due to their relevance to numerous applications. The wetting properties of a material are dictated by its surface chemistry (Emsley, J., Chemical Society reviews, 9(1):91-124 (1980); Wenzel, R. N., Industrial & Engineering Chemistry, 28(8):988-994 (1936)) and its topographic structure (Bhushan, B. et al., Philosophical transactions—Royal Society. Mathematical, Physical and engineering sciences, 367(1894):1631-1672 (2009); Gao, L. and McCarthy, T. Langmuir, 23(18):9125-9127 (2007); Gao, L. and McCarthy, T., Journal of the American Chemical Society, 128(28):9052-9053 (2006); Krupenkin, T. et al., Langmuir, 20(10):3824-3827 (2004)).
[0003] Many investigations have been conducted to understand the surface properties of superhydrophobic materials. A superhydrophobic surface is extremely difficult to wet; it typically has a static contact angle higher than 150° and a contact angle hysteresis less than 10°. Wang, S, and Jiang, L., Advanced materials, 19(21):3423-3424 (2007); Men, X. et al., Applied physics. A, Materials science & processing, 98(2):275-280 (2010); Bhushan, B. et al., Philosophical transactions—Royal Society. Mathematical, Physical and engineering sciences, 367(1894):1631-1672 (2009).
[0004] Superhydrophobic materials can be utilized as a protective coating for creating a self-cleaning, nonstick surface (e.g., for solar panels) and for preventing biofouling. Scardino, A. J. et al., Biofouling: The Journal of Bioadhesion and Biofilm Research, 25(8):757-767 (2009). They can be used as electrodes to store charge energy in a non-aqueous supercapacitor. They can also be employed to reduce hydrodynamic skin friction drag in laminar and turbulent flow. Rothstein, J., Annual Review of Fluid Mechanics, 42(1):89-109 (2010). Without intending to be bound by theory, the existence of a thin layer of trapped air at the liquid-solid interface is believed to allow a slip velocity at the wall of superhydrophobic material, reducing shear stress or momentum transfer from the flow to the wall. Ou, J. et al. Physics of Fluids, 16:4635-4643 (2004); Min, T.; Kim, J. Physics of Fluids 16:L55-L58 (2004); Daniello, R. J. et al. Physics of Fluids 21, online publ. no. 085103 (2009). This effect can produce advantages at macro- or micro-scale. For example, superhydrophobic materials could reduce fuel consumption of marine vessels and the efficiency of liquid pipelines. They also could be used in drug delivery devices to protect the device or drug from contact with blood, and they could be used to alter the mechanical response of cells.
[0005] In recent years, production of synthetic materials that exhibit superhydrophobic behavior has been reported. Among these materials, vertically aligned, multi-walled carbon nanotube arrays have gained enormous attention, due to their simple fabrication process and inherent two-length scale topographic structure. Efforts have been made to modify the surface chemistry of the carbon nanotube arrays so that their wetting properties can be tuned precisely. The carbon nanotube arrays can be made hydrophilic by functionalizing their surfaces with oxygenated surface functional groups that allow hydrogen bonds with water molecules to form or hydrophobic by removing those oxygenated surface functional groups from their surfaces.
[0006] Various oxidation processes can be used to functionalize the surface of carbon nanotube arrays, such as high-temperature annealing in air, UV/ozone treatment, oxygen plasma treatment, and acid treatment. Processes like high-temperature annealing in air and oxygen plasma treatment would be very costly to implement in large scale, not to mention highly probable to over-oxidize the carbon nanotube if an incorrect recipe were used. The acid treatment is generally hazardous, making it inconvenient to work with. On the other hand, the UV/ozone treatment is a simple, safe, and cost-efficient method of producing more hydrophilic carbon nanotubes.
[0007] However, no analogous simple, safe, cost-efficient process has yet been identified for producing superhydrophobic carbon nanotubes. Previously reported studies suggest that complicated processes are always involved in producing superhydrophobic carbon nanotube arrays. In order to make these arrays superhydrophobic, they have to be coated with non-wetting chemicals such as poly(tetrafluoroethylene) (PTFE), zinc (II) oxide, and fluoroalkylsilane, (Huang, L. et al., The journal of physical chemistry, B, 109(16):7746-7748 (2005); Lau, K. et al., Nano Lett., 3(12):1701-1705 (2003); Feng, L. et al., Advanced materials, 14(24):1857-1860 (2002)) or be modified by plasma treatments, such as CF4, CH4, and NF3. (Hong, Y. and Uhm, H., Applied physics letters, 88(24):244101 (2006); Cho, S. et al., Journal of materials chemistry, 17(3):232-237 (2007)); Balu, B. et al. Langmuir, 24:4785-4790 (2008). However, no prior art has reported a method for producing a superhydrophobic CNT array surface from pure CNTs grown by a simple self-assembly process.
[0008] In view of the foregoing, there is a need for a simple, safe, cost-efficient process for producing superhydrophobic carbon nanotubes. Such a process could help to speed the investigation and the commercial application of superhydrophobic carbon nanotubes. The present invention satisfies these and other needs.
BRIEF SUMMARY OF THE INVENTION
[0009] In one embodiment, the present invention presents a method for producing a hydrophobic carbon nanotube (CNT) array, the method comprising:
[0010] providing a vertically aligned CNT array; and
[0011] performing vacuum-pyrolysis on the CNT array to produce the hydrophobic nanotube array. Preferably, the hydrophobic nanotube CNT array is superhydrophobic (i.e., a superhydrophobic CNT array).
[0012] Preferably, the vacuum-pyrolysis step is performed under reduced pressure of about 0.5 torr to about 10 torr. More preferably, the vacuum-pyrolysis step is performed under reduced pressure of about 1 torr to about 5 torr.
[0013] Preferably, the vacuum-pyrolysis step is performed at a reaction temperature of about 100° C. to about 500° C. More preferably, the vacuum-pyrolysis step is performed at a reaction temperature of about 125° C. to about 300° C.
[0014] Preferably, the vacuum-pyrolysis step has a duration of about one hour to about five hours.
[0015] Preferably, the vertically aligned CNT is anchored on a surface. Preferably, the vertically aligned CNT array is a member selected from a single-wall CNT array, a multiwall CNT array, and a mixture of a single-wall CNT array and a multiwall CNT array.
[0016] Preferably, the vertically aligned CNT array is synthesized using a synthesis technique that is selected from chemical vapor deposition (CVD), laser ablation, and arc discharge. Preferably, the vertically aligned CNT is provided by a CVD process. In one aspect of the invention, the CVD process is continuous with the vacuum-pyrolysis step.
[0017] Preferably, the method for producing a hydrophobic CNT array further comprises an oxidation step before the vacuum pyrolysis step to remove amorphous carbon.
[0018] Preferably, the method for producing a hydrophobic CNT array further comprises removing contamination using the vacuum-pyrolysis step.
[0019] Preferably, an outer surface of the superhydrophobic CNT array is at least 85% free from oxygen-containing impurities. More preferably, the outer surface is at least 95% free from oxygen-containing impurities.
[0020] Preferably, the CNT array's static water droplet contact angle increases between about 5% to 45% after the vacuum-pyrolysis step. Preferably, the water droplet roll-off angle decreases by at least twofold. Preferably, more than one method is used to assess the array's superhydrophobicity (e.g., static water droplet contact angle and water droplet roll-off angle). Preferably, the static water droplet contact angle is between about 160° to 180°. Preferably, the water droplet roll-off angle is from about 1° to 5°, which means that a water droplet would not maintain a stable position on the surface of the array when the surface is tilted more than the roll-off angle.
[0021] Preferably, an outer surface of the superhydrophobic CNT array is at least 85% free from oxygen-containing impurities. More preferably, the outer surface is at least 95% free from oxygen-containing impurities. Still more preferably, the outer surface is at least 97% free from oxygen-containing impurities.
[0022] In another embodiment, the present invention presents a hydrophobic CNT array, wherein the hydrophobic CNT array is produced by any of the methods claimed herein. Preferably, the hydrophobic CNT array is superhydrophobic.
[0023] These and other aspects, objects and embodiments will become more apparent when read with the detailed description and drawings that follow.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] FIG. 1 . ( a ) Low-magnification scanning electron mircroscope (SEM) image of vertically aligned carbon nanotube array. ( b ) High-magnification SEM image of the same array showing the presence of some entanglements on the array's top surface.
[0025] FIG. 2 . ( a ) Water droplet on a superhydrophobic carbon nanotube array exhibiting an almost spherical shape with a 170° (±2°) static contact angle. ( b ) Time-lapse image of a water droplet bouncing off the surface of a superhydrophobic carbon nanotube array that was tilted 2.5°. Each frame was taken with a 17 ms interval.
[0026] FIG. 3 . Dispersion of carbon nanotubes with various wetting properties in industrial deionized (DI) water. The degree of CNT hydrophobicity is decreasing from left to right. The four tubes from left to right are: the dispersion of superhydrophobic CNTs (contact angle about 170°); hydrophobic CNTs (contact angle about 143°); hydrophilic CNTs (contact angle about 75°); and strongly hydrophilic CNTs (contact angle about 30°).
[0027] FIG. 4 . A typical Fourier-transform infrared (FTIR) spectra from superhydrophobic and hydrophilic carbon nanotube arrays showing strong peaks at 810-1320 cm −1 , 1340-1600 cm −1 , 1650-1740 cm −1 , and 2800-3000 cm −1 , which indicate the presence of C—O, C═C, C═O, and C—H x stretching modes respectively.
[0028] FIG. 5 . Electrochemical impedance modulus and phase-angle spectra of carbon nanotube arrays with various wetting properties in 1 M NaCl aqueous solution. Superhydrophobic and hydrophilic arrays are indicated by triangle and square markers respectively.
[0029] FIG. 6 . A process diagram for one embodiment of the present method for making superhydrophobic carbon nanotubes.
DETAILED DESCRIPTION OF THE INVENTION
I. Definition of Terms
[0030] The terms “a,” “an,” or “the” as used herein not only includes aspects with one member, but also includes aspects with more than one member. For example, an embodiment including “a vertically aligned CNT array” should be understood to present certain aspects with at least a second vertically aligned CNT array.
[0031] The term “about” as used herein to modify a numerical value indicates a defined range around that value. If “X” were the value, “about X” would generally indicate a value from 0.95X to 1.05X. Any reference to “about X” specifically indicates at least the values X, 0.95X, 0.96X, 0.97X, 0.98X, 0.99X, 1.01X, 1.02X, 1.03X, 1.04X, and 1.05X. Thus, “about X” is intended to teach and provide written description support for a claim limitation of, e.g., “0.98X.” When the quantity “X” only includes whole-integer values (e.g., “X carbons”), “about X” indicates from (X−1) to (X+1). In this case, “about X” as used herein specifically indicates at least the values X, X−1, and X+1.
[0032] When “about” is applied to the beginning of a numerical range, it applies to both ends of the range. Thus, “from about 5 to 45%” is equivalent to “from about 5% to about 45%.” When “about” is applied to the first value of a set of values, it applies to all values in that set. Thus, “about 7, 9, or 11%” is equivalent to “about 7%, about 9%, or about 11%.”
[0033] A “hydrophobic” surface indicates a surface that is difficult to wet because of its chemical composition or geometric microstructure. A hydrophobic surface has a static contact angle greater than 90°.
[0034] The term “or” as used herein should in general be construed non-exclusively. For example, an embodiment of “a composition comprising A or B” would typically present an aspect with a composition comprising both A and B. “Or” should, however, be construed to exclude those aspects presented that cannot be combined without contradiction.
[0035] The term “outer surface of the carbon nanotube array” as used herein includes a side or face of an array that is not directly affixed to its support. Typically, the outer surface would be more likely to contact the surrounding environment. For example, typical tests for roll-off angles would place the drop of liquid in contact with the outer surface of the array, not the inner surface, which would be the side of the array affixed to the support.
[0036] A “superhydrophobic” surface indicates a surface that is extremely difficult to wet because of its chemical composition or geometric microstructure. A superhydrophobic surface has at least one of the following characteristics: a static contact angle greater than 150°, a contact angle hysteresis less than 10°, or a roll-off angle less than 5°. Preferably, a superhydrophobic surface has two of these characteristics; more preferably, all three characteristics.
II. Embodiments
[0037] In one embodiment, the present invention presents a method for producing a hydrophobic carbon nanotube (CNT) array, the method comprising:
[0038] providing a vertically aligned CNT array; and
[0039] performing vacuum pyrolysis on the vertically aligned CNT array to produce the hydrophobic nanotube array. Preferably, the product CNT array is a superhydrophobic CNT array.
[0040] In one aspect, the present invention provides a vacuum pyrolysis process to render carbon nanotube arrays superhydrophobic. Without being bound by theory, such processes are believed to reverse the effects of oxidation by removing the oxygenated functional groups from the surface of the carbon nanotube, while maintaining the macroscopic structures and packing density of the arrays. Therefore, no deposition of any non-wetting foreign material (e.g., polyfluorocarbons such as poly(tetrafluoroethylene); metal salts, such as zinc (II) oxide) on the array is needed to make them superhydrophobic.
[0041] The temperature, pressure, and duration of the vacuum pyrolysis can affect the process's efficiency. Typically, a vacuum pyrolysis process that is performed at a moderate vacuum of 2.5 Torr and a temperature of 250° C. for three hours is sufficient to completely deoxidize the array.
[0042] Preferably, the vacuum-pyrolysis step is performed under reduced pressure of about 0.5 torr to about 10 torr, such as 0.5, 0.6, 0.7, 0.8, 0.9, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 torr. More preferably, the vacuum-pyrolysis step is performed under reduced pressure of about 1 torr to 5 torr or about 1 torr to 3 torr. Alternatively, the vacuum-pyrolysis step is performed under reduced pressure of about 1 torr to 3 torr. In general, lower pressure is preferable. Without intending to be bound by theory, a lower pressure during the reaction favors the oxygen-containing impurities' dissociation from the surface. Higher pressures disfavor the reaction, prolonging reaction times or even preventing production of superhydrophobic CNT arrays.
[0043] At sufficiently low pressure, however, further decrease in pressure produces only minor improvement in the reaction. For example, reaction pressures of 1 torr and 0.5 torr produces similar results in the vacuum pyrolysis (e.g., the process produced a similar superhydrophilic surface after approximately the same total reaction time).
[0044] When oxygen is present in the ambient gas, however, it can oxidize the surface of the starting CNT array, especially during pyrolysis at high temperatures and relatively high pressures (e.g., >10 torr). Preferably, the pyrolysis is free from oxygen. Alternatively and more preferably, the pyrolysis is substantially free of oxygen, thereby avoiding oxidation of the superhydrophobic CNT surface.
[0045] Preferably, the vacuum-pyrolysis step is performed at a reaction temperature of about 100° C. to about 500° C. such as 100° C., 150° C., 200° C., 250° C., 300° C., 350° C., 400° C., 450° C., or 500° C. More preferably, the vacuum-pyrolysis step is performed at a reaction temperature of about 125° C. to 300° C. (e.g., about 250° C.). Low temperatures (e.g., <100° C., <75° C., or <50° C.) are disfavored because they may not provide sufficient energy for the reaction to proceed efficiently. At high temperatures (e.g., >500° C., >575° C., >625° C., >700° C., >800° C., or >900° C.), the nanotubes or their support (especially if the support is an organic polymer) may partially or completely decompose. Generally, higher temperatures produce a higher chance of decomposition and a faster rate of decomposition.
[0046] Preferably, the vacuum-pyrolysis step has a duration of about one hour to about five hours. In general, higher temperature and lower pressures during the pyrolysis step tend to decrease the time required to produce a superhydrophobic CNT array. In some aspects, the vacuum pyrolysis can be continuous. In some aspects, the vacuum pyrolysis includes one or more periods of heating (e.g., two, three, or four heating cycles). In certain aspects, the results of the procedure are dependent on the total heating time rather than the number of heating cycles. In one preferred aspect, the present invention provides an iterative process in which the array is subjected to vacuum pyrolysis, assayed for superhydrophobicity, and re-exposed to the vacuum-pyrolysis conditions if the array were not found to be superhydrophobic.
[0047] CNT arrays are characterized by the orientation of the individual nanotubes composing the array. In a vertically aligned array, the axis running through the central point of a carbon nanotube's inner diameter is perpendicular to the array's base (i.e., if the nanotubes were pulled straight our from their bases, they would be oriented like the teeth of a comb or the hair on a head). This is in contrast to a horizontal array (e.g., like beads on a string) or a disordered array. Preferably, the CNT arrays of the present invention are vertically aligned arrays. Without intending to be bound by theory, this vertical alignment minimizes each CNT's contact area with water, reducing possible van der Waals forces.
[0048] Preferably, the CNT array is anchored on a surface. Non-anchored tubes can be scraped off, which makes it harder for them to maintain their superhydrophobic properties. Preferably, the CNT array is anchored to a silicon wafer base. Alternatively, the CNT array is anchored to a polymeric base (e.g., silicone). Sansom, E.; Rinderknect, D.; Gharib, M. Nanotech., 19, online publ. no. 035302 (2008). Procedures for making anchored, aligned nanotubes and nanotube devices are known to the skilled artisan (e.g., U.S. Patent Application 2009/0130370; U.S. Pat. No. 7,491,628; U.S. Patent Application 2008/0145616; U.S. Patent Application 2010/0196446; Han, Z. J. et al. Appl. Phys. Lett. 94, online publ. no. 223106 (2009); Men, X.-H. et al. Appl. Phys. A , DOI 10.1007/s00339-009-5425-6 (2009); Li, S. et al. J. Phys. Chem. B. 106, 9274-9276 (2002); and Zhang, L. et al. Langmuir 25:4792-4798 (2009), which are incorporated by reference in their entirety).
[0049] Individual carbon nanotubes within the array can be single-wall or multiwall. Single-wall nanotubes include one layer of carbon separating the inside and outside of the nanotube. The layer may include different patterns of carbon-carbon bonds depending on its two-dimensional bond geometry. Multiwall nanotubes include more than one layer of carbon separating the inside and outside. The multiple layers may be from a sheet wrapping over itself or from separate, concentric nanotubes. Preferably, the vertically aligned CNT array is a member selected from a single-wall CNT array, a multiwall CNT array, and a mixture of a single-wall CNT array and a multiwall CNT array.
[0050] A CNT array is also characterized by the packing density of the individual nanotubes composing the array. The packing density is the number of carbon nanotubes in an area; it is determined by the average distance between the different nanotubes in the array. In certain aspects of the present invention, a typical packing density is about 10 6 CNT/mm 2 . At this packing density, the distance between nanotubes at this density is about three to four times the diameter of the nanotube. A higher packing density is generally preferred because more closely associated nanotubes should make the array's surface more hydrophobic.
[0051] In certain preferred aspects, a major advantage of the present invention is its ability to make even very short superhydrophobic CNT arrays. Previous studies have suggested that short CNT arrays cannot become superhydrophobic. Lau, K. K. S. et al. Nano Lett. 3:1701-1705 (2009); Liu, H. et al. Soft Matter, 2:811-821 (2006). However, by using vacuum-pyrolysis methods, CNT arrays can be made superhydrophobic regardless of length. For example, a CNT array as short as 10 μm can be converted into a superhydrophobic array.
[0052] Preferably, the vertically aligned CNT array is synthesized using a synthesis technique that is selected from chemical vapor deposition (CVD), laser ablation, and arc discharge, using procedures commonly known to the skilled artisan. Preferably, the vertically aligned CNT is provided by a CVD process (e.g., Seo, J. W. et al. New J. Physics, 5, 120.1-120.22 (2003)).
[0053] Carbon nanotube arrays can also be prepared using other procedures known to the skilled artisan, such as those set forth in U.S. Pat. No. 7,491,628; U.S. Patent Application No. 2008/0145616; U.S. Patent Application No. 2003/0180472; and U.S. Patent Application 2010/0247777.
[0054] In some aspects, the CVD process is continuous with (or at least partially continuous with) the vacuum-pyrolysis step. For example, if the CVD process is continuous with the vacuum-pyrolysis step, the vacuum-pyrolysis process can be merged with the CNT growth process to form a continuous process (e.g., if there is no need to anchor the CNT array). During the cool-down from CVD synthesis of nanotubes, a vacuum is applied rather than a flowing inert gas. In some aspects, this modification eliminates a need for inert gas purging.
[0055] Some CNT arrays can contain residual catalyst particles or amorphous carbon, e.g., from the CNT synthesis. These impurities may create defects in the array. In certain aspects, the process set forth in the present invention further comprises an oxidation step before the vacuum-pyrolysis step to remove amorphous carbon. Preferably, if analytical techniques indicated a significant amount of catalyst particle leftovers or amorphous carbon in the CNT array, the array could be treated with ozone to oxidize the impurities before the vacuum pyrolysis (e.g., by exposure to 185 nm UV radiation in air for 1 hr).
[0056] Various other oxidation processes can be used to remove catalyst particles leftovers or amorphous carbon other than the ozone treatment. These other processes include hot air annealing, oxygen plasma treatment, and acid (usually a mixture of nitric acid and hydrochloric acid) treatment (e.g., Tohji, K. et al. Nature, 383:679 (1996)). While hot air annealing, oxygen plasma treatment, and acid treatment are each more effective in removing the catalyst particles leftovers and amorphous carbon than the ozone treatment, these processes are harsher so that the chance to over-oxidize the CNT array is high.
[0057] The easiest way to find catalyst particle leftovers and amorphous carbon is by performing electron microscopy analysis on the CNT samples; preferably, by using transmission electron microscopy (TEM) on the CNT samples. If the catalyst particles are only found inside the CNTs and if the thickness of amorphous carbon is much less than the diameter of the CNTs, the preliminary oxidation is unnecessary.
[0058] In one aspect, a preliminary oxidation is performed if (i) there is any sign of more than one catalyst particle on the average (e.g., preferably, the mean) found on the outer surface of each CNT or (ii) the thickness of amorphous carbon is more than the diameter of the CNT. For example, if TEM indicated 76 surface catalyst particles in a sample comprising 75 nanotubes, the array would be oxidized, but if TEM indicated only 75 or fewer particles in the sample, the array would not be oxidized. Alternatively, if the average number of outer surface catalyst particles is at least one, the array is oxidized to remove them. In some preferred aspects, about 25 to 250, about 50 to 200, or about 60 to 200 CNTs are examined by TEM to make this determination.
[0059] Some CNT arrays can contain other impurities or contaminants that may adversely affect the array's properties. These impurities may be volatile or may decompose into volatile products under vacuum-pyrolysis conditions. In certain aspects, the process set forth in the present invention further comprises removing contamination using the vacuum-pyrolysis step.
[0060] Preferably, the vacuum-pyrolysis step removes oxygen-bearing impurities from an outer surface of the CNT array. More preferably, the oxygen-bearing impurities are organic (i.e., carbon-containing) Oxygen-bearing, organic impurities can include organic compounds containing hydroxyl, carbonyl (e.g., aldehyde or ketone), or carboxyl (e.g., carboxylic acid) groups. Alternatively, the impurities can be organic, oxygen-bearing groups chemically bonded to the surface of the CNT array (e.g., a carboxy group with a covalent, carbon-carbon bond attaching it to a carbon nanotube).
[0061] Preferably, the water droplet roll-off angle decreases at least two-fold; preferably, the angle decreases from two- to twenty-fold. This is the general assay for superhydrophobicity, but others can be used. Preferably, more than one method is used (e.g., static water droplet contact angle and water droplet roll-off angle). Preferably, the static water droplet contact angle increases between about 5% to about 45%, such as 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, or 45% after the vacuum-pyrolysis step.
[0062] Preferably, the static water droplet contact angle is between about 160° to 180° (alternatively, the static water droplet contact angle is at least 150°; preferably, at least 160°; and more preferably, at least 170°). Surfaces with static water droplet contact angles of at least 160° are extremely hydrophobic, making them particularly useful (i.e., they are not subject to the “petal effect” allowing water to be pinned to the surface). Preferably, the water droplet roll-off angle is from about 1° to 5°, such as about 1°, 2°, 3°, 4°, or 5°; more preferably, the roll-off angle is from about 1° to 3° (e.g., about 1°). Preferably, the contact angle hysteresis is at most 10°, such as between about 1° to 10° (e.g., about 1°, 2°, 3°, 4°, 5°, 6°, 7°, 8°, 9°, or 10°); more preferably, the contact angle hysteresis is at most 5°.
[0063] The outer surface of the CNT array can also be monitored for oxygen-bearing bonds as a way to identify the method's progress. Such monitoring can be carried out with conventional methods (e.g., quantitative FTIR). Preferably, an outer surface of the superhydrophobic CNT array is at least 85% free from oxygen-containing impurities. More preferably, the outer surface is at least 95% free from oxygen-containing impurities. Still more preferably, the outer surface is at least 97% free from oxygen-containing impurities. Alternatively, the outer surface can be free from oxygen-containing impurities to the instrument's effective limit of detection.
[0064] In another embodiment, the present invention presents a superhydrophobic CNT array, wherein the hydrophobic CNT array is produced by any of the methods claimed herein. Preferably, the hydrophobic CNT array is superhydrophobic.
[0065] In certain preferred aspects, a major advantage of the present invention is the use of a simple, high-yielding procedure (vacuum pyrolysis) to produce superhydrophobic CNT arrays. Known methods of generating superhydrophobic CNT arrays are generally low-yielding, may involve corrosive reagents (e.g., the corrosive gases used in plasma treatment), and may change other properties of the CNT array's surface (e.g., treatment with metal oxide, which makes a continuous metal oxide surface). The present invention presents an alternative method for generating superhydrophobic arrays that is simpler and more efficient. In addition, it better preserves the microstructure of the CNT array.
[0066] In certain preferred aspects, another advantage of the present invention is the effects of the removal of oxygen-containing impurities from the CNT array's outer surface to produce superhydrophobic CNT arrays. Known methods of generating superhydrophobic CNT arrays are generally low-yielding, may involve corrosive reagents (e.g., the corrosive gases used in plasma treatment), and may change other properties of the CNT array's surface (e.g., treatment with metal oxide, which makes a continuous metal oxide surface). The present invention's removal of oxygen-containing impurities is a simpler and more efficient method of producing superhydrophobic arrays. In addition, it better preserves the microstructure of the CNT array.
III. Examples
[0067] It is understood that the examples and embodiments described herein are for illustrative purposes only. Various modifications or changes thereof will be suggested to persons skilled in the art, and they are to be included within the purview of this application and the scope of the appended claims. In addition, each reference provided herein is incorporated by reference in its entirety to the same extent as if each reference was individually incorporated by reference.
Example 1
Preparation of Superhydrophobic CNT Arrays
[0068] Carbon nanotube arrays used in this study were grown by the standard chemical vapor deposition (CVD) technique on a silicon substrate, using hydrogen and ethylene as the precursor gas. Sansom, E. et al., Nanotechnology, 19(3):035302 (2008). The average length of all the arrays was chosen to be about 14±4 μm ( FIG. 1 a ), which was about the minimum length that can be made using CVD techniques while preserving the overall vertical alignment and high packing density of the arrays ( FIG. 1 b ). The main reason this length was chosen is for the difficulties in producing a superhydrophobic surface out of short carbon nanotube arrays reported in the previously reported studies. Lau, K. et al., Nano letters, 3(12):1701-1705 (2003).
[0069] The CNT arrays were subjected to vacuum pyrolysis, typically at a vacuum of 2.5 Ton and a temperature of 250° C. for three hours. After the pyrolysis, the array's static contact angle was tested by conventional methods to determine its hydrophobicity. If conventional analytical methods indicated that the array was not superhydrophobic (e.g., if the static contact angle were less than 160°), the array was re-subjected to vacuum pyrolysis for another three hours (or longer if re-analysis after the second pyrolysis indicated that the array was still not superhydrophobic).
[0070] After being subjected to the vacuum-pyrolysis process, the carbon nanotube arrays exhibited extreme water repellency. Their superhydrophobicity was demonstrated by their ultra-high static contact angle of 170°(±2°) ( FIG. 2 a ) and very low contact angle hysteresis of 3°(±1°). These arrays also exhibit a very low roll-off angle of 1° (cf. FIG. 2 b , though FIG. 2 b shows a roll-off angle of 2.5°). The static contact angle, contact angle hysteresis, and roll-off angles were measured using standard techniques known by the skilled artisan (e.g., contact angles were measured with a contact angle goniometer).
Example 2
Comparison of Post-Vacuum-Pyrolysis CNTs with Control CNTs
[0071] Comparison of water-based dispersions of the pre- and post-vacuum pyrolysis carbon nanotubes provides further evidence of the vacuum pyrolysis products' superhydrophobicity. Superhydrophobic CNT arrays were prepared by the method of Example 1. These were compared with non-superhydrophobic control arrays prepared by the same initial procedure, but not subjected to vacuum pyrolysis (contact angle about 143°) as well as hydrophilic CNTs (contact angle about 75°); and strongly hydrophilic CNTs (contact angle about 30°). The water-based dispersions are obtained by scraping the nanotube arrays from their growth substrates and ultrasonically dispersing them in standard industrial deionized water for at least two hours.
[0072] The experiment demonstrated that nanotubes that have been subjected to vacuum-pyrolysis were not dispersed in water even after being sonicated for more than two hours ( FIG. 3 ). In contrast, the more hydrophilic nanotubes can be dispersed easily in water. From this finding, one can conclude that the vacuum-pyrolysis treatment is capable of completely deoxidizing individual nanotubes within the array.
Example 3
FTIR and Electrochemical Characterization of Superhydrophobic CNT Surface Chemistry
[0073] To study the effect of the vacuum-pyrolysis process on the surface chemistry of the hydrophilic CNTs, FTIR spectrometry analysis was conducted on array samples using standard methods for the skilled artisan. The superhydrophobic samples were compared with hydrophilic samples (contact angle 30°, as per Example 2's strongly hydrophilic CNTs). A small portion of the CNT array (<1 mm 2 ) was scraped from the growth substrate, dispersed in 50 ml deuterated dichloromethane, drop-cast onto a KBr window, and then dried overnight under mild vacuum (>5 torr) and without heating to remove the solvent. The FTIR spectrometry analysis was subsequently performed on the sample using an infrared laser with a wavelength of 2500-12500 nm.
[0074] Four strong bands were detected on the hydrophilic arrays at 810-1320 cm −1 , 1340-1600 cm −1 , 1650-1740 cm −1 , and 2800-3000 cm −1 , which indicate the presence of C—O, C═C, C═O and C—H x stretching modes respectively ( FIG. 4 ). The peaks at 970, 1028, 1154 and 1201 cm −1 correspond to C—O stretching modes (Kuznetsova, A. et al., Chemical Physics Letters, 321(3-4):292-296 (2000)), and the broad shoulder band at 810-1320 cm −1 suggests the existence of C—O—C bonds from ester functional groups. Sham, M. and Kim, J., Carbon, 44(4):768-777 (2006); Socrates, G., Infrared and Raman characteristic group frequencies: tables and charts, 3rd ed. ed., Wiley: Chichester (2001); Mawhinney, D. et al., Journal of the American Chemical Society, 122(10):2383-2384 (2000); Kim, U. et al., Physical Review Letters, 95(15):157402 (2005). The peaks at 1378, 1462, 1541 and 1574 cm −1 indicate the presence of C═C stretching vibration modes of the carbon nanotube walls. Kuznetsova, A. et al., Chemical Physics Letters, 321(3-4):292-296 (2000); Sham, M. and Kim, J., Carbon, 44(4):768-777 (2006); Socrates, G., Infrared and Raman characteristic group frequencies: tables and charts, 3rd ed. ed., Wiley: Chichester (2001); Mawhinney, D. et al., Journal of the American Chemical Society, 122(10):2383-2384 (2000). The narrow band at a peak of 1703 cm −1 corresponds to C═O stretching modes of either quinone or carboxylic acid ester groups. Kuznetsova, A. et al., Chemical Physics Letters, 321(3-4):292-296 (2000); Sham, M. and Kim, J., Carbon, 44(4):768-777 (2006); Mawhinney, D. et al., Journal of the American Chemical Society, 122(10):2383-2384 (2000); Kim, U. et al., Physical Review Letters, 95(15):157402 (2005).
[0075] These FTIR spectra show that the strength of all peaks associated with the C—O and C═O stretching modes of the superhydrophobic array is significantly lower than that of the hydrophilic one, suggesting that the oxygen desorption process does take place during vacuum-pyrolysis treatment. The strength of the C═C stretching modes also seems to decrease slightly, implying that the graphitic structures of the carbon nanotubes were still intact after the vacuum-pyrolysis treatment. The triplet with peaks at 2848, 2915 and 2956 cm −1 indicate C—H x bonds from the hydrocarbon functional group. Kim, U. et al., Physical Review Letters, 95(15):157402 (2005). This hydrocarbon triplet peaks seems to be unaffected by vacuum-pyrolysis process, implying that these peaks may be associated with contaminations in the FTIR instrument (Kim, U. et al., Physical Review Letters, 95(15):157402 (2005)) and have nothing to do with the wetting properties of the arrays.
[0076] Just like their wetting properties, the electrochemical properties of carbon nanotube arrays are dictated by their surface chemistry. As shown by the measured impedance modulus and phase angle spectra, carbon nanotube arrays with different wetting properties exhibit different electrochemical properties ( FIG. 5 ). For the superhydrophobic array, the frequency of constant impedance spans for three decades from 1 kHz to 1 MHz. On the other hand, the frequency of constant impedance for the hydrophilic arrays spans for six decades from 1 Hz to 1 MHz. At a low frequency of 10 mHz, the impedance modulus of the superhydrophobic array is about two orders of magnitude higher than that of the hydrophilic one. The impedance of the hydrophilic and the superhydrophilic CNT arrays were found to be about 650Ω and 162 kΩ respectively at frequency of 12 mHz in 1 M NaCl solution. This finding implies that the specific capacitance for hydrophilic and the superhydrophilic CNT array is about 3.3 F/g and 9.1 mF/g respectively.
[0077] Without being bound by theory, these findings are the result of a thin film of air on the interface between the surface of the superhydrophobic array and the aqueous electrolyte. This air film inhibits electrons transfer from the arrays and obstructs protons in the electrolyte to approach the surface of the array. On the other hand, the hydrophilic array is completely wetted by the aqueous electrolyte such that there is no air film that may inhibit electron transfer from the arrays. Because of the air film's presence film, the impedance of the superhydrophobic array was measured to be two orders of magnitude higher than that of the hydrophilic one.
Example 4
Flow-Diagram of One Embodiment of the Present Invention
[0078] This example illustrates a flow diagram of one embodiment of the present invention ( FIG. 6 ). The embodiment provides a vacuum pyrolysis process ( 100 ) to render carbon nanotube arrays superhydrophobic. In this instance, beginning with a vertically aligned CNT array ( 110 ), the array is analyzed for any catalyst particles or amorphous carbon contamination ( 117 ). If either or both of these are present, an oxidation process is performed to remove the contamination ( 121 ). Next, a vacuum-pyrolysis step is performed at a reaction temperature and duration as indicated herein (e.g., a temperature selected from about 100° C. to about 500° C. and a duration selected from about one hour to five hours) ( 125 ). After the vacuum-pyrolysis step is performed, the static contact angle is determined. In certain embodiments, if the static contact angle is within specification ( 136 ), the roll-off angle is determined. In one aspect, if the roll-off angle is within specification ( 147 ), the superhydrophobic CNT array is produced ( 163 ). If either of the static angle or the roll-off angle are not within specification, the vacuum-pyrolysis step ( 125 ) may be performed iteratively to produce the superhydrophobic CNT array ( 163 ).
CONCLUSIONS
[0079] In conclusion, the discoveries reported herein show that the wetting properties of carbon nanotube arrays can be altered by controlling the amount of oxygenated functional groups that are bonded to their surface. The CNT arrays can be made hydrophilic by oxidizing with, e.g., hot air, strong acids, UV/ozone, or oxygen plasma. The CNT arrays can be made superhydrophobic by deoxidizing with vacuum-pyrolysis treatment at moderate vacuum and temperature. Such vacuum-pyrolysis treatment is capable of removing the oxygenated functional groups that are attached to the CNTs' surfaces.
[0080] All publications and patent applications cited in this specification are herein incorporated by reference as if each individual publication or patent application were specifically and individually indicated to be incorporated by reference. Although the foregoing invention has been described in some detail by way of illustration and example for purposes of clarity of understanding, it will be readily apparent to those of ordinary skill in the art in light of the teachings of this invention that certain changes and modifications may be made thereto without departing from the spirit or scope of the appended claims. | The present invention provides efficient methods for producing a superhydrophobic carbon nanotube (CNT) array. The methods comprise providing a vertically aligned CNT array and performing vacuum pyrolysis on the CNT array to produce a superhydrophobic CNT array. These methods have several advantages over the prior art, such as operational simplicity and efficiency. The invention also relates to superhydrophobic CNT arrays. | 2 |
FIELD OF THE INVENTION
[0001] The present invention is generally directed to cryptography, and in particular to compressed RSA moduli.
BACKGROUND OF THE INVENTION
[0002] This section is intended to introduce the reader to various aspects of art, which may be related to various aspects of the present invention that are described and/or claimed below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present invention. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art.
[0003] To generate so-called Rivest-Shamir-Adleman (RSA) moduli for use in public cryptography one may proceed as follows.
[0004] Let N=pq be the product of two large primes. Let e and d denote a pair of public and private exponents, satisfying
[0000] ed≡ 1(mod λ( N )),
[0000] with gcd(e, λ(N))=1 and λ being Carmichael's function. As N=pq, we have λ(N)=1 cm(p−1, q−1). Given x<N, the public operation (e.g., message encryption or signature verification) consists in raising x to the e-th power modulo N, i.e., in computing y=x e mod N. Then, given y, the corresponding private operation (e.g., decryption of a ciphertext or signature generation) consists in computing y d mod N. From the definition of e and d, we obviously have that y d ≡x (mod N). The private operation can be carried out at higher speed through Chinese remaindering (CRT mode). Computations are independently performed modulo p and q and then recombined. In this case, private parameters are {p, q, d p , d q , i q } with
[0000] d p =d mod( p− 1),
[0000] d q =d mod( q− 1), and
[0000] i q =q −1 mod p.
[0005] We then obtain y d mod N as
[0000] CRT( x p , x q )= x q +q[i q ( x p −x q )mod p]
[0000] where x p =y dp mod p and x q =y dq mod q.
[0006] In summary, a RSA modulus N=pq is the product of two large prime numbers p and q, satisfying gcd(λ(N), e)=1. If n denotes the bit-size of N then, for some 1<n 0 <n, p must lie in the range [2 n−n 0 −1/2 , 2 n−n 0 −1] and q in the range [2 n 0 −1/2 , 2 n 0 −1] so that 2 n−1 <N=pq<2 n . For security reasons, so-called balanced moduli, with n=2n 0 , are generally preferred.
[0007] Typical present-day RSA moduli range in length from 1024 to 4096 bits, and it has become customary for applications to require moduli of at least 2048 bits. However, there are still programs and/or devices running the RSA-enabled applications that are designed to support only 1024-bit moduli.
[0008] It will be appreciated a solution that enables the compression moduli so that they can fit in shorter buffers or bandwidths would be greatly beneficial. Rather than storing/sending the whole RSA moduli, a lossless compressed representation is used. This also solves compatibility problems between different releases of programs and/or devices. In addition, such techniques can be used for improved efficiency: savings in memory and/or bandwidth.
[0009] One such solution is described by Vanstone and Zuccherato in “Short RSA Keys and Their Generation”, Journal of Cryptology, New York, N.Y., US, vol. 8, no. 8, 1995, pages 101-114, XP000853671. The solution enables specification of up to N/2 leading bits, but it is rather complicated, requiring e.g. factorization of the number given by the specified bits. In addition, the resulting moduli are relatively easy to factor.
[0010] Another such solution is described by Lenstra, Arjen K. in “Generating RSA moduli with a predetermined portion”; Advances in Cryptology—ASIACRYPT '98, volume 1514 of Lecture Notes in Computer Science, pp. 1-10; Springer 1998. This solution is an improvement upon the solution by Vanstone and Zuccherato as it is less complicated and as the resulting moduli are more difficult to factor.
[0011] However, neither of the prior art methods allow the predetermination of more than half of the bits of an RSA modulus.
[0012] The present invention, however, improves on Lenstra's generation method in that it for example allows greater compression.
SUMMARY OF THE INVENTION
[0013] In a first aspect, the invention is directed to a method for generating factors of a RSA modulus comprising a predetermined portion that can be larger than one half of the RSA modulus, the RSA modulus comprising at least two factors. First a value of a predetermined portion that the RSA modulus is to share is received. At least two candidate factors whose product shares at least a first part of the predetermined portion are generated. The at least two candidate factors are modified using Euclidean type computations until the resulting factors are prime and a product of the resulting factors fully shares the predetermined portion by using an extension of the Extended Euclidean Algorithm to evaluate a correcting value for each of the at least two factors; and adding respectively the correcting values to the at least two candidate factors to obtain at least two resulting factors; wherein the product of the resulting factors comprises the first shared part and shares the second part of the predetermined portion. Finally, the resulting factors are output in order to allow cryptographic operations using the resulting factors.
[0014] In a first preferred embodiment, the RSA modulus is a three-prime RSA modulus.
[0015] In a second preferred embodiment, the RSA modulus is of the form N=p r q.
[0016] In a third preferred embodiment, the generating step comprises the steps of: choosing a first candidate factor; and calculating a second candidate factor as the integer result of a division of a value and the first candidate factor, so that the product of the candidate factors shares at least the first part of the predetermined portion, the value having as many bits as the RSA modulus and sharing the predetermined portion.
[0017] In a fourth preferred embodiment, the extension of the Extended Euclidean Algorithm uses a sequence {u i , v i , d i } obtained by the Extended Euclidean Algorithm satisfying a u i +b v i =d i with a=q 0 and b=p 0 to derive two companion sequences {x i } and {y i } given by
[0000]
{
x
0
=
0
;
x
i
=
x
i
-
1
+
⌊
z
i
-
1
d
i
⌋
u
i
}
and
{
y
0
=
0
;
y
i
=
y
i
-
1
+
⌊
z
i
-
1
d
i
⌋
v
i
}
[0018] wherein z 0 =c and z i =z i−1 mod d i with c=2 l−1 +(N H 2 l mod p 0 ).
[0019] In a second aspect, the invention is directed to an apparatus for calculating factors of a RSA modulus comprising a predetermined portion that can be larger than one half of the RSA modulus, the RSA modulus comprising at least two factors. The apparatus comprises a processor adapted to: receive a value of a predetermined portion that the RSA modulus is to share; generate at least two candidate factors whose product shares at least a first part of the predetermined portion; modify the at least two candidate factors using Euclidean type computations until the resulting factors are prime and a product of the resulting factors fully shares the predetermined portion by: using an extension of the Extended Euclidean Algorithm to evaluate a correcting value for each of the at least two factors; and adding respectively the correcting values to the at least two candidate factors to obtain at least two resulting factors; wherein the product of the resulting factors comprises the first shared part and shares the second part of the predetermined portion. The processor is further adapted to output the resulting factors in order to allow cryptographic operations using the resulting factors.
[0020] In a third aspect, the invention is directed to a computer program product comprising program code instructions for the execution of the steps of the method according to the first aspect when said program is executed in a processor.
[0021] “Sharing” is to be interpreted as having the same value for the part that is shared, e.g. hexadecimal 1234567890abcdef and 123456789abcdef0 share 123456789 in the leading part of the numbers.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] Preferred features of the present invention will now be described, by way of example, with reference to the accompanying drawings, in which:
[0023] FIG. 1 illustrates an exemplary RSA modulus 10 according to the present invention;
[0024] FIG. 2 illustrates en example of the method of the present invention applied the RSA-2048 challenge; and
[0025] FIG. 3 illustrates an apparatus; for calculating compressed RSA moduli.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0026] The main inventive concept of the present invention is a method of providing a n-bit RSA modulus N for use in generating a key in an RSA-type cryptographic scheme where up to about two thirds of the n bits of N are predetermined.
[0027] FIG. 1 illustrates an exemplary RSA modulus 10 according to the present invention. l denotes the bit-length of N l . Hence n=n 0 +k′+l.
[0028] Let N=pq be the product of two large primes where p is (n−n 0 )-bit integer and q is a n 0 -bit integer so that N is an n-bit RSA modulus.
[0029] First, we compute p 0 and q 0 as follows.
[0000] 1. Using a pseudo-random number generator, produce a (n 0 +k′)-bit integer N H from a random seed s 0 :
[0000] N H :=N h ∥N m =2 n 0 +k′−1 PRNG( s 0 )ε[2 n 0 −1 ,2 n 0 −1]∥[0,2 k′ −1].
[0000] The skilled person will appreciate that it is naturally also possible to choose this value.
2. Randomly choose an integer p 0 ε[┌2 n−n 0 −1/2 ┐2 n−n 0 1].
3. Define
[0030]
q
0
=
⌊
N
H
2
1
p
0
⌋
.
[0000] The skilled person will appreciate that this choice for p 0 and q 0 implies that N H 2 l −p 0 q 0 =N H 2 l mod p 0 .
[0031] Next, we write p=p 0 +x and q=q 0 +y, and z=xy+2 l−1 −N l . Hence, we obtain
[0000] N=N H 2 l +N l =p 0 q 0 +( p 0 y+q 0 x )+ xy
[0000] q 0 x+p 0 y+xy−N l =N H 2 l −p 0 q 0 .
[0000] q 0 x+p 0 y+z= 2 l−1 +( N H 2 l mod p 0 )
[0032] We now have to find integer solutions (x, y, z) to the latter equation that fulfil |xy−z|=N l −2 l−1 |<2 l−1 . For this, we consider the sequence {u i , v i , d i } obtained by the Extended Euclidean Algorithm satisfying
[0000] a u i +b v i =d i with a=q 0 and b=p 0 .
[0033] The Extended Euclidean Algorithm produces three sequences: {u i }, {v i }, and {d i }. Below is an extension of the Extended Euclidean Algorithm that produces at least one different sequence implicitly or explicitly based on at least one of the sequences of the Extended Euclidean Algorithm.
[0034] Then we define z 0 =c and z i =z i−1 mod d i with c=2 l−1 +(N H 2 l mod p 0 ) and the two companion sequences {x i } and {y i } given by
[0000]
{
x
0
=
0
;
x
i
=
x
i
-
1
+
⌊
z
i
-
1
d
i
⌋
u
i
}
and
{
y
0
=
0
;
y
i
=
y
i
-
1
+
⌊
z
i
-
1
d
i
⌋
v
i
}
[0035] We have
[0000]
ax
i
+
by
i
=
ax
i
-
1
+
by
i
-
1
+
⌊
z
i
-
1
d
i
⌋
(
a
u
i
+
bv
i
)
=
ax
i
-
1
+
by
i
-
1
+
⌊
z
i
-
1
d
i
⌋
d
i
=
ax
i
-
1
+
by
i
-
1
+
z
i
-
1
-
(
z
i
-
1
mod
d
i
)
=
ax
i
-
1
+
by
i
-
1
+
z
i
-
1
-
z
i
=
ax
0
+
by
0
+
z
0
-
z
i
=
c
-
z
i
[0000] as requested, and there is a solution in the required range.
[0036] FIG. 2 illustrates en example of the method of the present invention applied the RSA-2048 challenge. As can be seen, the primes p and q generated by the method of the invention are such that the corresponding RSA modulus N=pq matches the RSA-2048 challenge on its upper two thirds (indicated by the underlined hexadecimal figures).
[0037] FIG. 3 illustrates an apparatus adapted to calculate RSA moduli. The apparatus 30 comprises a processor 31 , which may be a single processor or a combination of several processors, a memory 32 , a communication interface 33 that may be adapted to receive program code for executing the method from a storage medium 35 storing such program code, and a user interface 34 .
[0038] The processor 31 is adapted to generate RSA moduli, preferably according to the preferred method of the invention, the memory 32 is adapted to store data, and the communication interface 33 is adapted to communicate with other devices.
[0039] The apparatus 30 is adapted to receive, via either the communication interface 33 or the user interface 34 , a predetermined portion N H as input for calculating one or more RSA modulus that share the predetermined portion N H . When the modulus has been calculated, the device outputs the modulus through the user interface or, preferably, to another device for use in RSA cryptography.
[0040] It will be appreciated that, while the method according to the preferred embodiment of the invention fixes the leading bits of the modulus, it is also possible to fix the trailing bits of modulus N. More generally, it is possible to fix some leading bits and some trailing bits of N, or a number of bits scattered throughout N.
[0041] The method of the invention can be adapted to accommodate RSA moduli that are made of more than 2 factors, for example, 3-prime RSA moduli or RSA moduli of the form N=p r q.
[0042] The method according to the invention also applies when the common part of RSA modulus N, say N H , is shared among users or is common to all users for a given application. In such a case, there is no need to transmit it or the data needed to reconstruct the common part.
[0043] The skilled person will appreciate that RSA moduli generated using the present invention allow communicating parties in data communication system-to-exchange only about one third of the bits of N together with the data necessary to recover the said predetermined portion (a seed in the preferred embodiment).
[0044] Furthermore, the party generating the key in the said RSA-type cryptographic scheme may also only store about one third of the bits of N together with the data necessary to recover the said predetermined portion (a seed in the preferred embodiment).
[0045] Our new method considerably reduces the transmission and/or the storage requirements in the key generation for use in an RSA-type cryptographic scheme.
[0046] The skilled person will appreciate that the invention for example allows generation of compressed RSA moduli.
[0047] It will be understood that the present invention has been described purely by way of example. Each feature disclosed in the description and (where appropriate) the claims and drawings may be provided independently or in any appropriate combination. Features described as being implemented in hardware may also be implemented in software, and vice versa.
[0048] Reference numerals appearing in the claims are by way of illustration only and shall have no limiting effect on the scope of the claims. | A method for generating a compressed RSA modulus, allowing up to two thirds of the bits of a modulus N to be fixed. N has a predetermined portion N H , which comprises two parts N h and N m . A candidate RSA modulus that shares the N h part is generated, and the candidate is then modified using Euclidian-type computations until it shares both N h and N m . Also provided is an apparatus for calculating compressed RSA moduli according to the method and a computer program product. | 7 |
RELATED APPLICATION
[0001] This is a continuation of application Ser. No. 12/859,258 filed on Aug. 18, 2010 currently pending.
BACKGROUND OF THE INVENTION
[0002] This invention relates generally to earth anchors designed to be particularly useful as earth excavating tools. More particularly, it relates to a device that may be used as a shovel and as an anchor to secure a device in the ground. The application further relates to such a device integrated into an outdoor umbrella assembly.
[0003] Items typically inserted into the ground such as outdoor umbrellas, posts, and signs are often not adequately supported and at times are difficult to position as desired. These objects are particularly difficult to insert into ground hard enough to adequately support them in an upright position. Ground that is soft enough for easy insertion, however, generally provides little support. Attachments exist to aid the user in inserting such objects into the ground. Common attachments include spikes, screws and flat spades. Spike attachments aid the user by decreasing the force needed to pierce though the soil. Spikes lack the ability, however, to adequately support the object in softer soil. Screw anchors allow the user to secure the object by twisting it into the ground. Screw shaped anchor attachments can be difficult to work into hard ground, and may pullout of soft sand too easily. If of sufficient size to provide adequate purchase, screw attachments will often be large, heavy and cumbersome. Spade type attachments provide a relatively easy method of inserting the object into the ground, provide increased surface area to secure the object in sandy soil and, may double as a shovel-like digging tool to excavate a hole to provide additional purchase. Absent complicated folding mechanisms, these shovel like tools often lack the cross-sectional area needed to resist pullout.
[0004] A need exists for an anchorage device which provides a means to easily insert an object, such as a beach umbrella, into the ground while providing additional stability and resistance to pullout. Such an item would desirably be capable of creating a hole in the ground, be relatively simple to use and carry, and provide adequate pull-out resistance when placed in the ground.
[0005] One particularly useful application of the present invention is in the area of beach umbrellas. People enjoying outdoor activities commonly find it desirable to rest from the direct sun in a shady area. Such shade offers protection from the sun's heat and skin damaging radiation. Not all locations possess an adequate amount of shaded areas to relax, especially beaches, where beach dwellers often desire to experience the sensations of relaxing on a sandy beach while not succumbing to blistering sun.
[0006] Erecting a temporary sun shade, such as a beach umbrella, requires one to secure the umbrella shaft or pole to the ground to prevent movement. Such umbrellas are desirably lightweight for portability and possess a sufficiently large surface so as to adequately shade an individual. Such design criteria means that the slightest breeze can shift, lift and otherwise move the umbrella from its desired location. Fixing the umbrella to the ground generally requires tools or equipment to partially burry the umbrella shaft in soil that may vary from sand to dirt, clay or rock.
[0007] Heavy screw devices, complicated folding shovel like attachments, and spiked tips all have been used with limited success to anchor umbrellas into various soil conditions. Each has certain disadvantages. For instance, the screw devices can be awkward to transport and work well only in limited soil conditions, while complicated folding shovel like attachments are prone to breaking and can add unnecessary expense to their own construction, while simple spike attachments may be wholly inadequate in sandy soil conditions often found at the beach.
[0008] There remains a need for an attachment that provides a firm anchor in a variety of soil conditions, resists pull-out, lightweight, compact, self contained and preferably attached to the umbrella shaft itself. The attachment should also be relatively easy to manufacture and use no moving parts to assemble, manipulate, wear out or break.
BRIEF SUMMARY OF THE INVENTION
[0009] The disclosed anchoring device attaches to an umbrella shaft or pole and provides three general modes of use. Pressed into firm ground the wedge shape provides stability to the attached umbrella. Used as a shovel, the large flat blade allows the user to create a hole in the ground. A curved tip enables the user to easily break firm ground, while the bent shoulder step plates enable the user to comfortably exert the necessary pressure to pierce the soil. The device may then be used as a buried anchor, the device is placed in the hole and the removed soil is replaced, covering the device and enabling it to provide additional anchorage for the umbrella. A wedge shaped protrusion provides additional pull-out resistance and lateral stability.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] The invention is illustrated by the accompanying drawings, in which:
[0011] FIG. 1 is a side perspective view of the invention attached to an umbrella pole showing the invention employed as an anchor buried below the surface of the earth.
[0012] FIG. 2 is a front perspective view of the invention showing the invention employed as a digging apparatus.
[0013] FIG. 3 is a front perspective view of the invention showing a user pressing the invention into the ground with the user's foot.
[0014] FIG. 4 is a front perspective view of the invention.
[0015] FIG. 5 is a front view of the invention.
[0016] FIG. 6A is a top view of the invention with a blade having a slight curvature.
[0017] FIG. 6B is a top view of the invention with a planar blade.
[0018] FIG. 7A is a right side view of the invention shown in FIG. 6A .
[0019] FIG. 7B is a right side view of the invention shown in FIG. 6B .
[0020] FIG. 8 is a perspective view of another embodiment of the invention having opposing thumbscrews.
[0021] FIG. 9 is a side view of the embodiment having opposing thumbscrews.
[0022] FIG. 10 is a front view of an embodiment having a front face lacking a pronounced concave depression corresponding to the wedge shaped protrusion.
[0023] FIG. 11 is a side view of the invention shown in FIG. 10 .
[0024] FIG. 12 is a cross-section of the invention taken on line 12 - 12 of FIG. 10 showing the non-uniform thickness of the wedge shaped feature.
[0025] FIG. 13 is a front view of another embodiment of the invention formed from stamped sheet metal.
[0026] FIG. 14 is a side view of the embodiment shown in FIG. 13 .
[0027] FIG. 15 is a rear view of the embodiment shown in FIG. 13 .
[0028] FIG. 16 is a perspective top view of the embodiment shown in FIG. 13 .
[0029] FIG. 17 is a cross-section of the invention taken on line 17 - 17 of FIG. 13 .
DETAILED DESCRIPTION OF THE INVENTION
[0030] The drawings illustrate an invention that enables an individual to secure an object such as a beach umbrella in the ground.
[0031] FIG. 1 shows the preferred embodiment of the present invention 1 employed as an anchor below the surface 10 of the ground 5 , anchoring a device 13 , such as the shown beach umbrella 13 , in a desired orientation. The invention enables a user 3 to secure the umbrella 13 from movement and enjoy shade and wind protection in an otherwise unprotected area such as a beach 6 beside an ocean 7 . The device 13 to which the invention 1 is attached, may be secured in a non-releasable manner, including but not limited to: welding, bonding, gluing, riveting, press fitting, crimping or any combination thereof. The device may be secured to the invention 1 in a releasable manner including such means, including but not limited to: clamping, screwing, threading, bolting, clipping or any combination thereof. In this embodiment, the invention 1 is releasably secured at the neck or socket portion 110 . Here, the umbrella shaft 15 is inserted into the socket portion 110 of the invention 1 and releasably secured with thumb screw clamps 105 .
[0032] The invention's blade portion 120 increases the surface area upon which pressure exerted by the soil 5 , including sand, dirt, gravel, rock, clay, and mixtures thereof, can act upon the umbrella shaft 15 to maintain the desired position of the umbrella 13 . A wedge shaped feature 140 extends outward from the rear surface of the blade 120 . The wedge shaped feature 140 of the blade 120 provides additional surfaces 145 , 150 and 152 against which the soil 5 can act upon. The triangular shaped left lateral wedge surface 150 and corresponding right lateral wedge surface 152 , increase the lateral surface area and increase the blades resistance to side to side movement. The upper surface 145 of the wedge feature 140 increases the horizontal surface area thereby increasing the invention's resistance to being pulled vertically out of the ground 5 . While these surfaces 145 , 150 and 152 are shown in the present embodiment as planar, it should be understood that such surfaces may be curved and blended to form a protrusion in the general shape of a wedge having curved edges and non-planar surfaces.
[0033] FIG. 2 shows the user 3 employing the invention 1 as a digging apparatus. The blade portion 120 enables the user to remove soil 5 forming a hole 30 . Once the user 3 digs the hole 20 to an adequate depth, the user can place the invention 1 and attached device to be anchored 13 , in the hole 30 . After placement, the user 3 refills the hole with the previously removed soil 35 securing the device in the desired orientation.
[0034] The rounded tip 125 aids the user in breaking though firm soil. The wedge shaped feature 140 on the rear surface 123 of the blade portion 120 provides additional strength. The present embodiment shows the wedge shaped feature 140 having a corresponding concave depression 143 on the front 121 surface of the blade portion 120 . The depression 143 further aids in removal of the dirt by enabling the invention to hold a larger volume of soil 5 that it could without the depression 143 . Alternatively, the invention may possess a wedge feature 140 , but lack the concave wedge shaped depression 143 . In such an embodiment, the blade 120 would have a generally flat front surface 121 . Furthermore, regardless whether the invention possesses a wedge shaped depression 143 , the invention may have a planar blade 120 , or as shown in the present embodiment the blade 120 may have a slight curvature where the right lateral edge 126 and the left lateral edge 128 are slightly curved upward toward the front face 121 of the invention 1 .
[0035] FIG. 3 shows the user 3 pressing the invention 1 into the soil 5 . The shoulder 127 of the blade 120 provides a surface for the user 3 to step. In the preferred embodiment, the shoulder 127 protrudes rearward and is connected to the top edge 122 of the blade 120 . The shoulder 127 also provides additional strength to the blade 120 and improved pullout resistance when the blade 120 is buried.
[0036] FIG. 4 shows the invention 1 from a front perspective view. The front surface 121 of the blade 120 possesses a concave wedge shaped indention 143 corresponding to the wedge shaped feature 140 . This wedge shaped indention 143 possesses a right lateral surfaces 147 and a left lateral surface 149 that aid in resisting side-to-side movement of the invention 1 when buried in soil 5 . Lateral surfaces 147 and 149 also provide additional strength to the blade 120 . The neck or socket portion 110 possesses a bore 113 adapted for receipt of the shaft 15 of the object to be secured 13 . One or more thumb screws 105 secure the shaft 15 inside the bore 113 of the socket 110 .
[0037] FIG. 5 shows a front view of the invention 1 . The blade portion 120 is generally rectangular in shape, but may possess a rounded tip 125 to aid the user in piercing harder soil 5 .
[0038] The blade rear surface 123 , surrounds the wedge shaped feature 140 on the sides and top, while the tip portion 125 of the blade rear surface 123 , is located below the wedge shaped feature surrounds the wedge 140 on the bottom side. The wedge 140 , is thus encircled by the rear surface of the blade on the left, right, top and bottom sides of the wedge 140 . The rear surface 123 provides a non-parallel surface to the rear wedge surface, against which the soil may act. The blade and wedge surfaces form a simply connected surface, having no holes in them through which soil could pass, reducing the effectiveness of the device as an anchor.
[0039] FIG. 6A shows a top view of the invention 1 . The blade portion 120 possesses a curvature for increased strength and to help contain soil when the device is used as a digging apparatus. Thumbscrews 105 are threaded into the rear portion of the socket 110 . From this perspective, the top portion of each shoulder 127 of the blade 120 can be seen. The shoulder 120 provides increased surface area to allow the user to press the invention 1 into the soil with increased comfort. The shoulder 127 also helps to increase the overall strength of the blade 120 .
[0040] FIG. 6B shows a top view of an alternative embodiment of the invention 1 where the blade 120 lacks a curvature. In this embodiment, the blade surface is planar, with or without the wedge shaped depression 143 . The planar blade 120 increases resistance for increased stability when anchored in soil 5 .
[0041] FIG. 7A shows a left side view of the invention 1 . The wedge shaped feature 140 can be seen protruding rearward from the blade 120 of the invention forming a horizontal surface area 145 for increased vertical pullout resistance. The socket portion 110 is shown at a slight angle from the blade 120 to aid in removal of soil when used as a digging apparatus. The socket portion 110 possesses a capped end portion 112 to prevent ingress of sand or other soil into the hollow tubular portion of the socket 110 and prevent egress of the secured shaft 15 past the lower end of the socket 110 .
[0042] FIG. 7B shows a left side view of the alternative embodiment of the invention 1 shown in FIG. 6B where the blade 120 surface is planar, with or without the wedge shaped depression 143 .
[0043] FIG. 8 shows a front prospective view of an alternative embodiment of the invention 1 having opposing thumb screws 105 on the left and right sides of the tubular neck portion 110 . A pointed tip 225 provides easier penetration into hard soils. The wedge shaped feature 140 provides additional pull out stability while a shoulder 127 provides a comfortable step along the top edge of the blade 120 for pressing the wedge shaped feature below the surface of the soil.
[0044] FIG. 9 shows a side view of the alternative embodiment having opposing thumb screws 105 . The inventions wedge shaped feature possesses an upper surface 145 positioned below the top edge 127 of the blade 120 .
[0045] FIG. 10 shows a front view of another alternative embodiment of the invention 1 where the front face 121 of the blade 120 lacks a pronounced concave depression corresponding to the wedge shaped feature. The front face 121 is generally planar where the blade 120 is planar, or following the contour of the shape of the blade 120 . In this particular embodiment, the front face 121 follows the slight curvature of the blade 120 , the blade 120 being slightly curved about a vertical axis.
[0046] FIG. 11 shows a side view of the alternative embodiment of the invention 1 lacking a pronounced concave depression corresponding to the wedge shaped feature. The wedge shaped feature 140 protrudes from the rear face 123 of the blade portion 120 of the invention 1 . The top surface 145 of the wedge 140 is positioned below the top edge 127 of the blade 120 .
[0047] FIG. 12 shows a cross-section of the invention 1 taken on line 12 - 12 in FIG. 10 . The wedge shaped feature 140 possesses a non-uniform thickness of the wedge portion as measured from the front face 121 of the blade portion 120 to the rear wedge surface 151 . In this embodiment one can observe the narrowing of the thickness of the wedge from the top of the wedge 140 to the bottom of the wedge 140 . The neck portion 110 possesses a bore 113 . The bore 113 forms an inner bore surface 115 . As with other embodiments of the invention 1 , the top surface 145 of the wedge 140 is positioned below the top edge 122 of the blade 120 . When the user steps upon the shoulder 127 of the blade 120 , pushing the blade 120 such that the top edge 122 is level with the top surface of the soil, the top surface 145 of the wedge 140 will be below the soil surface, providing additional pull-out resistance of the invention.
[0048] FIG. 13 shows a front view of yet another embodiment of the invention 1 where the invention 1 is formed from a sheet of material such as being stamped from sheet metal. The elongated neck portion 110 possesses a thumb screw 105 for securing the end of an umbrella shaft in the interior bore 113 of the neck portion 110 . The blade 120 has a slightly wider shape toward the top of the blade, and narrows toward the middle and bottom portion s of the blade when viewed from the front. The neck portion 110 is formed from the folding or wrapping of a portion of the sheet to form a cylindrical socket or bore for receiving the end of the umbrella shaft. The blade portion 120 is formed from another portion of the sheet being bent into the desired shape. The wedge shaped feature 140 may also be bent from this portion of the sheet. This construction saves assembly steps by forming the socket, blade and wedge from the same sheet material, while allowing the use of curves to strengthen the structure of the invention.
[0049] FIG. 14 shows a side view of the embodiment of the invention. In the current embodiment, the blade 120 and lower portion of the elongated neck 110 possess a curved shape. The protruding wedge 140 is and lower tip portion of the blade 120 are angled from the axis of the neck portion 110 . This angle provides additional vertical pull out resistance, while the top surface 145 of the wedge 140 provides additional pull out resistance.
[0050] FIG. 15 shows a rear view of the current embodiment of the invention. In this embodiment, the elongated neck portion 110 is formed from the wrapping of the sheet metal in a cylindrical shape. The cylindrical shape forms a bore 113 in which the end of a shaft of an umbrella may be secured. In this particular embodiment, the walls of the elongated neck portion 110 do not completely encircle the bore 113 , leaving a vertical opening 117 along the rear surface of the neck portion 110 .
[0051] FIG. 16 shows a top perspective view of the current embodiment of the invention 1 . The neck portion 110 possesses a generally cylindrical inner bore 113 . The bore 113 forms an inner bore surface 115 . The thumbscrew 105 passes from the outer circumferential surface of the neck portion and through the inner bore surface 115 . In this particular embodiment, the wall of the neck portion 110 do not completely encircle the bore 113 , leaving a small gap 117 .
[0052] FIG. 17 is a partial cross-section side view of the lower portion and tip 125 of the blade portion 120 of the current embodiment of the invention 1 taken on line 17 - 17 of FIG. 13 . The interior of the wedge may possess an optional fillet plate 153 , or otherwise possess a filled section, in the upper corner of the wedge. The fillet plate 153 may be welded, riveted, glued, or otherwise secured to the blade portion 120 of the invention 1 . The fillet plate 153 or filled section allows for easier penetration of the blade 120 into the soil. | A combination earth anchor and shovel capable of being used as an earth excavating tool and anchoring device having a particular application to secure an outdoor umbrella in soil. | 4 |
RELATED APPLICATIONS
[0001] This application claims benefit of U.S. Provisional Patent Application Ser. No. 61/668,973, filed Jul. 6, 2012, entitled “Video Door Monitor Using SmartTV with Voice Wakeup,” which is hereby incorporated by reference for all purposes, as if set forth herein in its entirety.
TECHNICAL FIELD
[0002] The present disclosure relates to video door monitors, and more specifically to a video door monitor that can be used in conjunction with a television, such as a “smart” television having an internal processor and firmware, and that can utilize a voice/audio trigger and wakeup system to monitor for a door chime and to allow a viewer to converse with a person at a door of a building or residence.
BACKGROUND OF THE INVENTION
[0003] Door monitors typically include a camera that is connected by a wireless or wire line connection to a dedicated monitor. While such systems allow a person, such as an occupant of a building, to see who is at a door to the building, they are dedicated systems that do not provide any alternate functionality.
SUMMARY OF THE INVENTION
[0004] A system for monitoring an entrance to a building or residence is provided that can work in conjunction with an existing connected television set. The system includes a door camera system, such as a wireless door camera system, for generating image data of a person at a predetermined location, such as at a door to a building. A television system displays the image of the person in coordination with a program, such as by generating a picture-in-picture display of the person at the door.
[0005] Other systems, methods, features, and advantages of the present disclosure will be or become apparent to one with skill in the art upon examination of the following drawings and detailed description. It is intended that all such additional systems, methods, features, and advantages be included within this description, be within the scope of the present disclosure, and be protected by the accompanying claims.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0006] Aspects of the disclosure can be better understood with reference to the following drawings. The components in the drawings are not necessarily to scale, emphasis instead being placed upon clearly illustrating the principles of the present disclosure. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views, and in which:
[0007] FIG. 1 is a diagram of a system for providing a wireless door monitor in accordance with an exemplary embodiment of the present disclosure;
[0008] FIG. 2 is a diagram of a system for providing door monitor functionality at a television set in accordance with an exemplary embodiment of the present invention;
[0009] FIG. 3 is a diagram of a system for providing a door camera system in accordance with an exemplary embodiment of the present disclosure; and
[0010] FIG. 4 is a diagram of an algorithm for controlling the operation of a door monitoring system, in accordance with an exemplary embodiment of the present disclosure.
DETAILED DESCRIPTION OF THE INVENTION
[0011] In the description that follows, like parts are marked throughout the specification and drawings with the same reference numerals. The drawing figures might not be to scale and certain components can be shown in generalized or schematic form and identified by commercial designations in the interest of clarity and conciseness.
[0012] Existing wireless door monitors that allow a user to see and talk with persons at a doorway to a building require the use of dedicated display units that significantly add to the total cost of the monitor system. While televisions with wireless networking capabilities are available, a number of problems exist with the simple integration of such wireless door monitors to televisions through a wireless network. As a preliminary matter, the television is not always on, and using the wireless connection to continuously monitor signals received from the door monitor would continuously consume power even when the television is off, thus causing the television to fail to meet Energy Star® requirements for standby mode operation. As such, a person in the building would need to go turn on the television after hearing a door chime.
[0013] In addition, when the television is on and the door monitor camera is activated, a number of problems are presented. First, it would normally be necessary to reduce the volume of the television in order to enable a conversation with the person at the door. In addition, the ambient sound from the television will make it difficult or impossible for the person at the door to understand the person in the building.
[0014] The present disclosure allows a remote wireless door camera and wireless television to be connected to a home wireless network. When the television is on and the doorbell chime is activated, the television will display the video from the remote door camera in a small picture in picture window. Far field voice processing and acoustic echo cancellation on the audio input processor in the television is also used to enable two-way audio communication, without requiring the user to lower the volume on the television. In addition, the person at the door will only hear the person speaking and will not hear the audio from program playing on the television. In one exemplary embodiment, the television can implement facial recognition processing using a camera in the television to detect whether the user is watching the television, so as to allow the door bell chime to be disabled if the user is watching television.
[0015] When the television is off, television status data can be transmitted to the remote door camera, so when someone is at the door and presses the doorbell, the doorbell can be configured to generate a unique audio signal that can be detected by the microphone of the television in a standby mode of operation. In standby mode, the voice and audio trigger enabled television waits for a predetermined voice command, such that the audio input processor in the television can also be configured to recognize a predetermined doorbell audio signal that will cause it to wake up and display the image from the door camera.
[0016] In another exemplary embodiment, a control system, such as a remote control or voice recognition and control system of the television, in conjunction with the television door monitor system can be used to remotely unlock or open the door. In this exemplary embodiment, the door lock will include a controllable lock/unlock mechanism.
[0017] The present disclosure lowers the cost required to provide a video door monitor system because a dedicated display is not required, although a dedicated display can also or alternatively be used. The present disclosure also allows the television to be operated in a low power standby condition by detecting the door bell chime, using DSP processing to isolate and uniquely identify the door bell chime and to not falsely wake up from other sounds in the room. The present disclosure does not add any additional hardware costs to a television that has voice control, camera, facial recognition and a standby mode with voice command activated wake up. The present disclosure also improves the audio performance and audio quality of a video door monitor by using acoustic echo cancellation and far field pickup, for both inside and outside communications.
[0018] FIG. 1 is a diagram of a system 100 for providing a wireless door monitor in accordance with an exemplary embodiment of the present disclosure. System 100 includes television system 102 , door camera system 104 , wireless network 106 and door lock system 116 , each of which can be implemented in hardware or a suitable combination of hardware and software.
[0019] As used herein, “hardware” can include a combination of discrete components, an integrated circuit, an application-specific integrated circuit, a field programmable gate array, or other suitable hardware. As used herein, “software” can include one or more objects, agents, threads, lines of code, subroutines, separate software applications, two or more lines of code or other suitable software structures operating in two or more software applications or on two or more processors, or other suitable software structures. In one exemplary embodiment, software can include one or more lines of code or other suitable software structures operating in a general purpose software application, such as an operating system, and one or more lines of code or other suitable software structures operating in a specific purpose software application. As used herein, the term “couple” and its cognate terms, such as “couples” and “coupled,” can include a physical connection (such as a copper conductor), a virtual connection (such as through randomly assigned memory locations of a data memory device), a logical connection (such as through logical gates of a semiconducting device), other suitable connections, or a suitable combination of such connections.
[0020] Television system 102 includes acoustic echo canceller 108 , door monitor system 110 , camera and microphone system 112 and network interface 114 . Acoustic echo canceller 108 performs acoustic echo cancellation, far field voice processing and other suitable audio signal processing on audio signals generated by camera and microphone system 112 . In one exemplary embodiment, acoustic echo canceller 108 can subtract an audio signal generated by programming (such as programming provided from a digital cable media, a satellite media, an auxiliary device such as an optical, magnetic disk or memory device storage and playback media), such as from a signal that is being displayed on television system 102 , from vocal audio signals, such as to allow a television viewer to converse with a person at the door of a building that is being monitored by door camera system 104 . In this exemplary embodiment, the television viewer can continue to watch the programming while engaging in a conversation with the person at the door of the building. In another exemplary embodiment, door monitor system 110 can freeze the current programming to allow the viewer to converse with the person at the door without interrupting the current programming. Door monitor system 110 can also receive voice commands to either allow the current programming to continue or to freeze the current programming, can be programmed to either continue with programming or to freeze programming, or can perform other suitable functions. Door monitor system 110 can interface with door camera system 104 and door lock system 116 through wireless network 106 or in other suitable manners.
[0021] Door camera system 104 is disposed at a doorway, gate or other suitable location and can include one or more cameras, one or more microphones, one or more door chime buttons, motion sensors or other suitable systems and components to allow a person at a door of a building or in another suitable location to be detected and to allow video and audio data to be transmitted to television system 102 , and to allow audio data to be transmitted to door camera system 104 from television system 102 . Although one door camera system 104 is shown, a plurality of door camera systems 104 can also or alternatively be used.
[0022] Wireless network 106 can be implemented as a home wireless network, a cellular wireless network or other suitable wireless networks. Likewise, wireless network 106 can be replaced with a wire line network, can be implemented in conjunction with a wire line network or in other suitable manners so as to provide connectivity between the components of system 100 .
[0023] Door monitor system 110 allows a door camera system 104 and door lock system 116 to be controlled from television system 102 , such as by using voice commands, remote control commands, hand motions or in other suitable manners. In one exemplary embodiment, door monitor system 110 can include security systems for controlling access to door camera system 104 and door lock system 116 , such as by transmitting and receiving communications from door camera system 104 and door lock system 116 using encrypted tokens or other suitable encryption, by responding to authentication requests or in other suitable manners. For example, encryption and authentication processes can be used that would not otherwise be implemented, such as using encryption keys based on user commands, user images or other suitable data, to prevent an external adversary from gaining control of door lock system 116 or other suitable systems. For example, a user can set a verbal password for door monitor system 110 , which is then encrypted and stored by door lock system 116 and provided when a user wants to remotely open door lock system 116 . The encrypted verbal password can then be decrypted and compared to a user-entered verbal password, so as to prevent an external adversary from being able to activate door lock system 116 from outside of the dwelling. Door monitor system 110 can generate picture-in-picture or full screen displays showing the person at the door, and can interface with other property monitor systems. Door monitor system 110 can also be configured to process speech signals to extract voice commands to select one of a plurality of cameras, to change the camera view (zoom in, zoom out, pan) and to perform other suitable functions.
[0024] Door lock system 116 can be implemented using a relay, an electronic or magnetic latching mechanism or in other suitable manners, so as to allow a lock on a door to be remotely controlled. In one exemplary embodiment, door lock system 116 can include encryption or other suitable security mechanisms to prevent door lock system 116 from being hacked or otherwise operated by unauthorized personnel. Although one door lock system 116 is shown, a plurality of door lock systems 116 can also or alternatively be used.
[0025] In operation, system 100 allows a television viewer to see a person at a door of a building or in other suitable locations, to interact with the person and to remotely unlock one or more doors. System 100 can use existing hardware solutions for wireless doorway monitoring and wireless lock control, and allows a viewer of a television to access the wireless doorway monitoring and wireless lock control systems without interrupting programming.
[0026] FIG. 2 is a diagram of a system 200 for providing door monitor functionality at a television set in accordance with an exemplary embodiment of the present invention. System 200 includes door monitor system 110 and door audio processor 202 , facial recognition system 204 , television status system 206 , chime monitor system 208 and door lock release 210 , each of which can be implemented in hardware or a suitable combination of hardware and software, and which can be one or more software systems operating on a television control processor.
[0027] Door audio processor 202 receives audio signals from a door camera system and generates audio signals from a viewer or other suitable persons to be transmitted to the door camera system. In one exemplary embodiment, door audio processor 202 can interface with a television audio system such as acoustic echo canceller 108 and can receive a program audio signal from the television audio system that is also being provided to the television speakers. Door audio processor 202 can also receive an audio signal from one or more microphones of the television system or television audio source, such as camera and microphone 112 , and can perform acoustic echo cancellation, far field voice processing and other suitable processing on the microphone signals to subtract the program audio signal from the microphone signal, to perform acoustic echo cancellation and to otherwise process the microphone signal for transmission to the door camera system, so as to allow the viewer to converse with the person at the door camera system. Door audio processor 202 can also interface with the television audio system to control the volume of the audio signal from the door camera system, so as to prevent the need for the user to adjust a volume control and to accommodate for audio signals from the door camera system that are louder or softer than usual, such as when the person at the door camera system is standing near to or far from a microphone associated with the door camera system, is talking loudly or softly, or in other suitable situations. Door audio processor 202 can also perform automated speech processing to detect command words in speech signals, so as to allow a user to control system operation through spoken commands.
[0028] Facial recognition system 204 uses a camera associated with the television system to determine whether a viewer is present, such as to determine whether to generate an on screen display of a person at the door monitor system, to generate a chime, or to otherwise generate an indication that there is a person present at the door monitor system. In one exemplary embodiment, a television system may be on but there might not be a viewer present, such that an audible chime or other audible alert is generated to notify an occupant that there is a person present at a door of the building. Likewise, facial recognition system 204 can disable the audible chime or signal if it is determined that a viewer is present, can generate control data to cause an on-screen display to be generated, or can perform other suitable functions.
[0029] Television status system 206 generates television status data for use by a door camera system or other suitable systems. In one exemplary embodiment, when the television system is off or in standby mode, the door camera system, door chime system or other suitable systems can be enabled to generate an audible chime or other suitable signals to alert an occupant that there is a person at a door of the building or in other suitable locations.
[0030] Chime monitor system 208 provides audio monitoring functionality to detect a door chime or other suitable signals. In one exemplary embodiment, an existing doorbell or other suitable systems may be present to allow a person at a door of a building to indicate that they are present. Likewise, chime monitor system 208 can be configured to detect a knock at a door or other suitable sounds, such as by processing audio data with a digital signal processor that has stored knock audio profile data or by using a training procedure, can be configured to cause the television system to go from an off or standby mode to an active mode, so as to generate a video image from the door camera system, or can be configured to perform other suitable systems.
[0031] Door lock release 210 allows a user to generate a door unlock control to unlock a door. In one exemplary embodiment, the door can have a lock with an associated door lock system that has a relay, an electric or magnetic lock or other suitable locking or unlocking devices, where the door remains locked until a door unlock control is received, or until the lock is manually operated. In another exemplary embodiment, door lock release 210 can also be used to lock a door, such as where an entrance to a building includes a space accessed by a first unlocked door and a second locked door, such as to allow an intruder to be locked into the space and to be detained until police or other security personnel arrive.
[0032] In operation, system 200 allows a television to be used to interface with a door camera system, a door lock system and other suitable systems, to allow a viewer to see who is at a door without interrupting programming, to notify an occupant that a person is at the door when the television is off, and to perform other suitable functions.
[0033] FIG. 3 is a diagram of a system 300 for providing door camera system in accordance with an exemplary embodiment of the present disclosure. System 300 includes door camera system 104 and television status interface 302 , chime disable system 304 , network interface 306 and presence detection system 308 , each of which can be implemented in hardware or a suitable combination of hardware and software and which can be one or more software systems operating on a processor.
[0034] Television status interface 302 receives television status data, such as to allow system 300 to determine whether a television is on or not. In one exemplary embodiment, when television status data indicates that the television is on, a door chime can be disabled, such as when a viewer is also present and watching the television. In another exemplary embodiment, television status data can indicate that there is no viewer present even when a television is on, such that the chime remains enabled.
[0035] Chime disable system 304 controls a door chime, such as to disable the door chime when a viewer is watching television and receives an on-screen notification that a person is present at system 300 .
[0036] Network interface 306 allows system 300 to interface with a wireless network, a wire line network or other suitable networks. In one exemplary embodiment, network interface 306 can interface with a home wireless network, such as an 802.xx wireless network, a cellular wireless network, an Ethernet wire line network, a power line data network, or other suitable wireless or wire line networks.
[0037] Presence detection system 308 can detect when a person is present at system 300 . In one exemplary embodiment, presence detection system 308 can use facial recognition (either locally or remotely, such as at a television system), infrared detectors, video motion detectors, weight detectors or other suitable mechanisms to detect when a person is at a door to a building or in other suitable locations, and to generate a suitable signal, such as a digital or analog electrical signal, a digital or analog wireless signal or other suitable signals that can be received and processed by door monitor system 110 or other suitable systems.
[0038] In operation, system 300 allows a door camera system to interface with a television system, to allow the door camera system to transmit audio and video data to the television system and to allow system 300 to generate audio signals received from the television system on one or more speakers. Door camera system can also include one or more microphones, one or more cameras and other suitable components.
[0039] FIG. 4 is a diagram of an algorithm 400 for controlling the operation of a door monitoring system, in accordance with an exemplary embodiment of the present disclosure. Algorithm 400 can be implemented in hardware or a suitable combination of hardware and software, such as one or more software systems operating on one or more processors.
[0040] Algorithm 400 begins at 402 , where a person is detected at a door. In one exemplary embodiment, facial recognition algorithms (either locally at a door monitor system or remotely, such as at a television system), infrared detector monitoring algorithms, motion detector algorithms, weight detector monitor algorithms or other suitable algorithms can generate data that indicates that a person has been detected, such as one or more bits of data having a predetermined format. The detection data can be transmitted to a detection system operating on a processor at a television or to other suitable systems. The algorithm then proceeds to 404 .
[0041] At 404 , it is determined whether a television system is on. In one exemplary embodiment, television status data stored in a data register can be checked to determine whether the status data indicates that the television system is off or in standby mode, whether the status data indicates that the television system is on but where no viewer is present, or other suitable status data can be checked, such as by sending a request to a television system and determining whether a response has been received. If it is determined that the television system is on, the algorithm proceeds to 406 , otherwise, the algorithm proceeds to 414 .
[0042] At 406 , it is determined whether a viewer is present, if the determination has not been previously performed, such as by processing image data from a camera system of the television system with a facial recognition algorithm or in other suitable manners. If it is determined that a viewer is present, the algorithm proceeds to 408 and an audible chime is disabled, such as to prevent the chime from sounding and interrupting programming on the television. The algorithm then proceeds to 412 . Otherwise, the algorithm proceeds to 410 where an audible chime is generated, such as to alert an occupant that a person is at a door of the building, so the occupant can use the television system to view the person at the door. The algorithm then proceeds to 412 .
[0043] If it is determined at 404 that the television is not on, the algorithm proceeds to 414 , where a chime is generated. In one exemplary embodiment, the chime can be generated by the door monitor system. Alternatively, the chime can be generated by activation of a doorbell control by the person at the door or in other suitable manners. The algorithm then proceeds to 416 , where the chime is detected. In one exemplary embodiment, a standby audio processor system of the television system can monitor audio signals for voice commands, for predetermined chime audio signals, or for other suitable audio data. The algorithm then proceeds to 418 , where the television system is turned on, is transitioned from a standby mode to an active mode, or other suitable processes can be performed. The algorithm then proceeds to 412 .
[0044] At 412 , an on screen display is generated at the television system. In one exemplary embodiment, the on screen display can be a picture-in-picture display where the current programming continues without interruption. In another exemplary embodiment, the current programming can be stopped and the on screen display can be a full screen display. In another exemplary embodiment, programming, voice commands, remote control commands or other suitable controls can be used to change from a picture-in-picture display to a full screen display, to allow the camera image to zoom in to the face of the person at the door or to zoom out to a selected field of view, other cameras can also or alternatively be viewed (such as perimeter, interior or exterior cameras), or other suitable controls can be provided. The algorithm then proceeds to 412 .
[0045] At 412 , it is determined whether an answer should be transmitted to the door camera system. In one exemplary embodiment, voice commands, remote control commands or other suitable commands can be received and processed, a default setting can be used or other suitable commands or programming can be used to determine whether an answer should be transmitted. If it is determined that an answer should not be transmitted, the algorithm proceeds to 422 and terminates, such as by discontinuing the generation of the audio and video data being received from the camera system, by playing a recorded message that informs the person at the door camera system that the occupants do not want to be disturbed, or in other suitable manners. Otherwise, the algorithm proceeds to 424 , where audio communication with the door camera system is enabled and acoustic echo cancellation, far field voice processing and other suitable audio processing is performed. In one exemplary embodiment, the audio processing can be used to cancel out audio signals from programming on the television set, to adjust the audio signal from the door camera system (such as to amplify or reduce the audio signal), or to perform other suitable functions. The algorithm then proceeds to 426 .
[0046] At 426 , it is determined whether an unlock control should be generated. In one exemplary embodiment, voice commands, remote control commands or other suitable controls can be used to generate control data for a door lock mechanism, including encryption, authentication or other suitable security processes that are used to prevent the door lock mechanism from being activated or deactivated by unauthorized personnel. In another exemplary embodiment, a determination to activate a second door lock can be made, as previously described, or other suitable determinations can be made at 426 . If it is determined that the door should not be unlocked or that no other actions should be taken, the algorithm proceeds to 428 and terminates. Otherwise, the algorithm proceeds to 430 , where the unlock control data or other suitable control data is generated and transmitted.
[0047] In operation, algorithm 400 allows a door monitor system to alert an occupant or other suitable persons such as monitoring personnel at a remote site that a person is at a door of a building, and further allows the occupant, viewer or other suitable personnel to communicate with the person at the door. In this manner, a door camera system can be accessed by a television viewer without interrupting programming or other suitable processes can be performed.
[0048] Although the exemplary embodiments described above include a television system, a dedicated door monitor can also or alternatively be used.
[0049] It should be emphasized that the above-described embodiments are merely examples of possible implementations. Many variations and modifications may be made to the above-described embodiments without departing from the principles of the present disclosure. All such modifications and variations are intended to be included herein within the scope of this disclosure and protected by the following claims. | A system for monitoring an entrance to a building comprising a door camera system for generating image data of a person at a predetermined location and a television system for displaying the image data, wherein the television system is configured to display the image data in coordination with a program. | 7 |
BACKGROUND OF THE INVENTION
The present invention relates to a loading device for sequential feeding of bars into a lathe, e.g. the numerical control type.
In the field of automatic lathes the problem of sequentially feeding the bars to be machined is well known. Indeed, it is usually necessary to respect relatively short loading and unloading times while at the same time avoiding bar positioning errors and jamming of the machine. This is particularly problematical when the bars to be supplied are relatively heavy because of the inertia of the settling movements that the bars make. For example, in known loaders the bars are often made to run on a moving inclined plane at the end of which is an axial sliding guide for the bar toward the machine tool. The bar running on the inclined plane thus falls into the guide. Especially in the case of relatively heavy bars the lateral velocity of the bar in falling on the guide is such as to make likely jumping over the guide and consequently jamming of the loader. It is also likely that a relatively heavy bar in falling into the guide would cause vibrations and shocks which could damage the structure.
SUMMARY OF THE INVENTION
The general purpose of the present invention is to supply a loader for machine tools such as lathes which would feed with high speed and accuracy even heavy bars while avoiding possible jamming situations.
In view of said purpose it was sought to provide in accordance with the present invention a loading device for loading of bars into a machine tool comprising in combination:
inclined plane chutes for arrival of a bar against stops in a withdrawal position,
an axial sliding guide for a bar with said guide being arranged beyond said stops and aligned with an axial insertion position for a bar in the machine tool,
raising elements arranged substantially between the withdrawal position and the guide and having the upper surface inclined downward in the direction of said guide and terminating with a raised stop part arranged substantially vertically to the guide and the raising elements being mobile between a first nonoperating position below the chutes and the guides and a second operating position above the stops and the guides in which the raising elements raise the bar placed in the withdrawal position up to a height greater than the stops to cause sliding on the upper inclined surface toward the guide to a stop position against the stop and upon return of the raising elements into the nonoperating position the bar slides into the stop position being placed on the underlying guides,
pushing and gripping means moving coaxially to the guide to move axially the bar placed on them along the guide to introduce the bar into the machine tool add subsequently withdraw at least a remnant thereof from the machine tool along the guide, and
disengagement means for the bar remnant from the pushing meads for its falling to an unloading position.
BRIEF DESCRIPTION OF THE DRAWINGS
To clarify the explanation of the innovative principles of the present invention and its advantages compared with the known art there is described below with the aid of the annexed drawings a possible embodiment by way of nonlimiting example applying said principles. In the drawings:
FIG. 1 shows a schematic plan view of a feeding and unloading device in accordance with the present invention,
FIGS. 2 and 3 show perspective, schematic and partial views of a first and second part respectively of the device of FIG. 1,
FIG. 4 shows a schematic and partial view of a cross section of the device of FIG. 1,
FIG. 5 shows a side view of a third part of the device of FIG. 1,
FIG. 6 shows a perspective, schematic and partial view of a fourth part of the device of FIG. 1, and,
FIG. 7 shows an enlarged view of a detail of the device of FIG. 1.
DETAILED DESCRIPTION OF THE INVENTION
With reference to the figures FIG. 1 shows schematically a loading device indicated generically by reference number 10 comprising a first part 11 and a second part 12 of a guide for a bar 13 to be fed by axial insertion into a machine tool, e.g. a spindle 14 belonging to a lathe of the known art and therefore not further illustrated. Laterally and parallel to the first and second parts 11, 12 is placed a chute 16 made up e.g. of several parallel cross pieces 16 for supply of bars 15 (shown in broken lines in FIG. 1) to be taken sequentially. As seen also in FIGS. 2 and 4, at the end of the inclined plane are placed stops 17 against which butts the first bar of the sequence 15 supplied on the chute.
As seen in FIG. 1 the first and second parts of the guide comprise a guide made up of an aligned sequence of guide supports in the shape of the letter U 20', 20 respectively.
Said supports can be e.g. supported by arms 21 appropriately anchored in a slightly elastic manner for absorption of vibrations during operation of the machine.
As seen better in FIG. 2, aligned below between the first bar to be withdrawn butted against the stops 17 and the guide 20, 20' are arranged raising elements consisting of raising or withdrawal blades 22. As is clear also from FIG. 4, the blades 22 have the upper surface formed generally like the letter V with a first part 23 inclined downward away from the stops 17 and terminating with a second part or stop rise 24, e.g. consisting of a surface oppositely inclined upward after passing a stop point 26 vertically beneath the guides. The two surfaces 23, 24 identify a V-shaped seat for reception of a bar as described below.
The blades 22 are supported by means of a vertical movement to move simultaneously on command between first lower nonoperating positions shown in solid lines in FIG. 4 and upper operating or withdrawal positions shown in broken lines in the same Figure.
In this manner, when the blades move to the operating position they raise the first bar arranged against the stops 17 until they cause it to jump over the stops. The bar indicated by reference number 13' in FIG. 4 slides on the plane 23 until it is received at the stop point 26 (bar 13" in FIG. 4 ). The stop rise 24 inclined upward blocks the movement of the bar which is positioned accurately thanks to the advantageous V shape given by the meeting of the inclined planes 23 and 24. At this point the blades 22 are again lowered into the nonoperating position and the transferred bar is thus rested in the guides 20, 20' (bar 13 in FIG. 4) Transfer of the bar between the chute 16 to which the bars can be fed manually or by an automatic magazine and the axial insertion guide in the machine is in this manner fast and safe, the bar being accurately stopped vertically to the guide before being deposited with a simple vertical movement.
FIG. 3 shows schematically add partially a possible embodiment of a vertical movement mechanism for the blades. As seen in said Figure the blades 22 are all supported by a beam 25 longitudinal to the machine 10 and moving vertically thanks to carriages or roller 27 placed at its two ends and sliding along vertical guides 29. The beam 25 is connected through two crank mechanisms 31 to the ends of a control rod 32 which translates horizontally by means of a piston operated linear actuator 33. FIG. 3 shows a single end of the beam and single crank mechanism.
The other end and the other crank mechanism are equivalent. As seen in the figures the crank mechanism consists of a bell crank 34 pivoted centrally at 35 to a fixed support 36. One end of the bell crank 34 is pivoted to the control rod 32 while the other end is pivoted to a tierod 52 which is in turn pivoted to the beam 25, in this manner it is clear that when the actuator 33 moves the rod 32 horizontally the crank mechanisms push the beam 25 to slide with its ends along the guides 29 causing said vertical movement of the plurality of blades.
When a bar 13 is housed in the guides 20, 20' aligned with the loading input of the machine tool a pushing unit pushes axially the bar to introduce it in the machine and then withdraw from the machine the residual bar length of the machining.
To limit the length of the device the solution described below has been found advantageous.
The guide supports 20 belonging to the guide part 12 closer to the machine to be fed are stably aligned with the bar inlet in the machine tool 14. The guide part 11 comprises a carriage 18 on which is supported the first row 20' of supports in the shape of the letter U and a second row 30 of supports parallel to the first. The carriage 18 is mobile transversely to the extension of the guides to bring into alignment with the fixed guide 12 alternately the guide supports 20' or 30 of the part 11. The transverse movement of the carriage 18 can be e.g. obtained by its running along tracks 28 by means of a compressed air piston 19.
As seen again in FIG. 1, aligned with the guides 20' and 30 are placed two pushers 37, 38 mobile axially to the respective guides to slide in the channel formed thereby. The pusher 37 is mobile with its free end between a retracted position or rear stop shown in solid lines in the figures and a front stop position beyond the guides 20' shown in broken lines and indicated generally by reference number 37'. The pusher 38 is mobile with its free end between a retracted or rear stop position in which as seen again in FIG. 1 it is received with its free end just beyond the guides 30 and a front stop position in which its free end is near the machine 14.
For example, in FIG. 6 is shown a possible device for movement for the pusher 37 and the one for the pusher 38 could be equivalent. As seen in said Fig. the end of the pusher opposite the guides is supported by a carriage 39 running along a track 40 parallel to the guides by means of a powered chain 41.
As seen again in FIG. 1 the pusher 38 has on its pushing end a known elastic pincer engagement element 42 for a tail end of the bar to be fed. Facing the pincer 42 are placed means of insertion add extraction comprising an inserter & extractor device 43 for the bar in said pincer. With reference to FIG. 5 the inserter & extractor 43 comprises a pair of jaws 44 facing each other transversely to the extension of the bar to be gripped and commanded to close by means of an actuator 45, e.g. a compressed air or oil piston, with gear and rack movements. The inserter & extractor is also mobile longitudinally to the bar to draw near or away from the engagement end 42 of the pusher 38. To obtain the longitudinal movement of the inserter & extractor the carriage 18 comprises a first upper plate 46 bearing the inserter & extractor and the guides 20', 30. Said first-plate 46 slides with its own lower rollers 47 along longitudinal tracks 48 by means of a piston 49. The tracks 48 and piston 49 are supported in turn on a second plate 50 below the first and in turn running with its own rollers 51 along the guides 28 by means of the piston 19 to allow the above mentioned transverse alignment movement of the guides 20' or 30 with the guides 20.
During use, operation of the loading device along a feed cycle is as follows.
As described above, when it is necessary to load a new bar in the machine tool 14 the piston 33 is operated so that the blades 22 rise toward their upper operating position while withdrawing the bar waiting against the stops 17. Upon reaching the top of the stops 17 the bar slides along the upper inclined surface of the blades 22 until it stops in position 26 and is then laid on the aligned guides 20, 20' by means of the lowering of the blades toward their lower nonoperating position.
At this point the pusher 37 is operated toward the bar tail to push the bar with its head toward and inside of the spindle 14 of the machine tool. The bar thus begins to rotate, being entrained by the rotation of the machine tool spindle. The guides 20, 20' are mounted as mentioned in a dampened manner and dampen the vibrations caused by the high speed rotation of the bar. As known in the field, the guides 20 can have upper counterguides which close like jaws once the bar 13 has been fed between them. For clarity of the drawings said counter guides are not shown but can be equivalent to the guides and are readily imaginable by a person skilled in the art.
Once the first pusher 37 has reached with its pushing end the position 37' which is slightly greater than the position of the head of the second pusher 38, the first pusher is backed off to its starting position and the piston 19 is operated to align the guides 20, 30 for sliding of the second pusher 38.
The inserter & extractor is then commanded to tighten its jaws on the tail end of the bar 13 as shown in FIG. 7 and the piston 49 is commanded to cause the inserter & extractor 43 to complete a rearward travel toward the head 42 of the pusher. In this manner the bar on the guides is engaged with its tail end in the engagement element 42. The element 42 is supported on the pusher in a freely rotating manner around the axis (in accordance with the known art easily imaginable by a person skilled in art) so that the bar is free to rotate even if engaged therein. Once the jaws 44 have reopened, the bar engaged and supported by the pusher 38 can thus be pushed thereby further inside the machine tool for the desired machining. After completion of the machining cycle the pusher 38 returns to its rest position as shown in FIG. 1, withdrawing from the machine tool the residual bar length still engaged with the element 42. The extractor 43 is commanded to grip the length and the carriage 18 completes its forward travel from the position shown in broken lines to the position shown in solid lines in FIG. 7 so as to withdraw the length from the engagement element 42. The jaws 44 then open and the length falls into a collection area (not shown). The loader is thus ready for a new cycle, withdrawing the next bar from the inclined plane 16 and feeding it to the machine tool.
At this point it is clear that the pre-set purposes of having a reliable and fast loader have been achieved. Naturally the above description of an embodiment applying the innovative principles of the present invention is given merely by way of example and therefore is not to be taken as a limitation of the patent right claimed here. For example, the exact form and proportions of the various parts and the length of the loader and the number of guide elements 20, 20', 30 can vary depending on the peculiar requirements of use and dimensions of the bar to be handled. | A loading device for sequential loading of bars in machine tools comprises chutes (16) for arrival of a bar against stops (17) for stopping in a withdrawal position. Beyond the stops (17) there is a guide (20,20') for axial sliding of a bar in a direction aligned with the inlet of a machine tool (14). Raising elements (22) have their upper surface (23) inclined and terminating with a stop part (24) arranged substantially vertically to the guide (20,20'). Said raising elements (22) are mobile between a first position below the chutes (16) and the guides (20,20') and a second position above the stops (17) and the guides (20,20') in which they raise the bar placed in the withdrawal position to cause sliding onto the upper inclined surface (23) toward the guide ( 20,20') to a stop position (26). Upon return of the raising elements to the first position the bar in the stop position (26) is placed on the underlying guides (20,20') to be pushed by (pushers) (37,38) into the machine tool. | 1 |
RELATED APPLICATION
[0001] This application is a continuation of U.S. patent application Ser. No. 11/757,304, filed Jun. 1, 2007, which is hereby incorporated herein by referenced in its entirety.
BACKGROUND
[0002] 1. Field of the Invention
[0003] The present invention relates to a method and apparatus for controlling a lifting magnet of a materials handling machine for which the source of DC electrical power is a DC generator. It finds particular application in conjunction with lifting magnets used on crawlers in the scrap metal industries.
[0004] 2. Prior Art
[0005] Lifting magnets are commonly attached to crawler booms to load, unload, and otherwise move scrap steel and other ferrous metals.
[0006] While lifting magnets have been in common use for many years, the systems used to control these lifting magnets remain relatively primitive. During the “Lift”, a DC current energizes the lifting magnet in order to attract and retain the magnetic materials to be displaced. At the end of the “Lift”, when the materials need to be separated from the lifting magnet, most of the controllers automatically apply a reversed voltage across the lifting magnet for a short period of time to allow the consequently reversed current to reach a fraction of the “Lift” current. This phase is known as the “Drop” phase, during which a magnetic field in the lifting magnet of the same magnitude but in an opposite direction of the residual magnetic field is produced that the two fields cancel each other. When the lifting magnet is free of residual magnetic field, all scrap metal detaches freely from the lifting magnet. This is known as a “Clean Drop”.
[0007] Some known control systems operate to selectively open and close contacts that, when closed, complete a “Lift” or “Drop” circuit between the DC generator and the lifting magnet. At the end of the “Lift”, which is called the “discharge” and at the end of the “Drop”, which is called the “secondary discharge”, these systems generally use either a resistor or a varistor to discharge the lifting magnet's energy. The higher the resistor's resistance value or varistor breakdown voltage, the faster the lifting magnet discharges, but also the higher the voltage spike across the lifting magnet. High voltage spikes cause arcing between the contacts. In addition, fast rising voltage spikes also eventually wear out the DC generator collector and its winding insulation, the lifting magnet insulation, and the insulation of the cables connected to the lifting magnet and the generator. To withstand these voltage spikes, generally in the magnitude of 750 V DC with systems using DC generators rated 240 V DC, the lifting magnet, cables, and the control system contacts and other components must be constructed of more expensive materials, and must also be made larger in size. These systems waste lifting magnet's energy. Lifting magnet's energy is transformed into heat, dissipated through a voltage suppressor or resistor bank. This results in poor system efficiency and oversized components to dissipate the heat.
[0008] To avoid these issues, some other known control systems connect directly to DC generator excitation shunt field. They eliminate arcing across contacts and minimize voltage spikes in the lifting magnet circuit but at the expense of a slower response time, caused by the induced DC generator time constant.
SUMMARY
[0009] A new and improved method and apparatus for controlling a lifting magnet is provided.
[0010] In one embodiment, the lifting magnet energy produced during the “Lift” phase is returned to the DC generator which in turn converts it back into mechanical energy.
[0011] In one embodiment, a Transient Voltage Suppressor (TVS) is provided to control DC generator maximum voltage when current is reversed in the DC generator.
[0012] In one embodiment, a circuit is provided to protect the TVS against overload. TVS overload can occur, for example, by accidental disconnection between the controller and the DC generator such that energy stored in the lifting magnet cannot be returned to the DC generator.
[0013] In one embodiment, at least a portion of the energy stored in the lifting magnet is returned to the source rather than being dissipated in resistor, varistor, or other lossy elements.
[0014] In one embodiment, switching of current for the magnet is provided by solid-state devices.
[0015] In one embodiment, the control system is configured to reduce voltage spikes in the lifting magnet circuit.
[0016] In one embodiment, the control system is configured to increase the useful life of the lifting magnet, the generator supplying power to the lifting magnet, and/or the associated circuitry.
[0017] In one embodiment, the control system is configured to reduce the “Drop” time. Shorter “Drops” helps to increase production by reducing lifting magnet cycle times. Some existing systems are using a resistor, which causes voltage to decay with the current leading to a longer discharge time. This invention uses a constant voltage source provided by the DC generator to discharge the lifting magnet energy, allowing a faster discharge.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] FIG. 1 schematically illustrates a lifting magnet controller circuit.
[0019] FIG. 2 graphically shows a voltage and current signals as the lifting magnet is operated through “Lift” and “Drop” cycle.
[0020] FIG. 3 shows the circuit of FIG. 1 during the “Lift” mode.
[0021] FIG. 4 shows the circuit of FIG. 1 during the “Lift” off mode.
[0022] FIG. 5 shows the circuit of FIG. 1 during the Discharge mode.
[0023] FIG. 6 shows the circuit of FIG. 1 during the “Drop” mode.
[0024] FIG. 7 shows the circuit of FIG. 1 during the “Drop” off mode.
[0025] FIG. 8 shows the circuit of FIG. 1 during the secondary discharge mode.
[0026] FIG. 9 shows the circuit of FIG. 1 during an open circuit in the “Lift” mode.
[0027] FIG. 10 shows the circuit of FIG. 1 during the Freewheel TVS protection mode after the “Lift” mode.
[0028] FIG. 11 shows the circuit of FIG. 1 during an Open circuit in the “Drop” mode.
[0029] FIG. 12 shows the circuit of FIG. 1 during the Freewheel TVS protection mode after the “Drop” mode.
[0030] FIG. 13 , consisting of FIGS. 13A-13K , is a schematic diagram of one embodiment of the logic controller.
DETAILED DESCRIPTION
[0031] FIG. 1 schematically illustrates a lifting magnet controller circuit that includes a logic controller 108 . Outputs from the logic controller 108 are provided to respective switches 101 , 102 , 103 and 104 . One of ordinary skill in the art will recognize that logic controller 108 can be a Printed Circuit Board, Programmable Logic Controller, etc. The switches 101 - 104 are configured in an “H” bridge arrangement to provide current to a magnet 150 . The switches 101 - 104 can be any type of mechanical or solid-state switch device so long as the devices are capable of switching at a desired speed and can withstand the desired current and voltage. For convenience, and not by way of limitation, FIG. 1 shows the switches 101 - 104 as insulated gate bipolar transistors. One of ordinary skill in the art will recognize that the switches 101 - 104 can be bipolar transistors, insulated gate bipolar transistors, field-effect transistors, MOSFETs, etc.
[0032] In FIG. 1 , a first output from the logic controller 108 is provided to a gate of the switch 101 , a second output from the logic controller 108 is provided to a gate of the switch 102 , a third output from the logic controller 108 is provided to a gate of the switch 103 , a fourth output from the logic controller 108 is provided to a gate of the switch 104 . An emitter from the switch 101 is provided to a first terminal of the magnet 150 and to a collector of the switch 102 . An emitter from the switch 103 is provided to a second terminal of the magnet 150 and to a collector of the switch 104 . Flyback diodes 111 - 114 are provided to respective collectors and emitters of the switches 101 - 104 .
[0033] A positive output from a DC generator 101 is provided through a fuse 130 to a first terminal of a current sensor 121 . A second terminal of the current sensor 121 is provided to a first terminal of a transient voltage suppressor (TVS) 123 , and to the collectors of the switches 101 and 103 . A negative output from the DC generator 101 is provided through a current sensor 122 to a first terminal of a resistor 124 and to the emitters of the switches 102 and 104 . A second terminal of the resistor 124 is provided to a second terminal of the TVS 123 .
[0034] The transistors, 103 and 102 form the “Lift” circuit, and transistors 101 and 104 form the “Drop” circuit. One of ordinary skill in the art will recognize that when any of the diodes 111 - 114 are forward biased, the switch 101 - 104 can be closed to provide a current path in parallel with the diode (e.g., to protect the diode, to provide a lower impedance path for current, etc.) Thus, for example, during discharge and/or drop, the switches 104 and 101 can be closed to provide current through the switches, or open to allow current to flow through the respective diodes. The current sensors 121 , 122 can be configured as Hall Effects sensors, current shunts, resistors, current transformers, etc. The current sensors 121 , 122 monitor current and detect “Drop current threshold” current, short-circuits, and ground faults. The system 100 (shown in FIGS. 1 and 3 - 12 as the system 100 with the addition of the generator 101 , the fuse 130 and the magnet 150 ). controls the maximum voltage when current reverses direction in the generator. The resistor 124 is provided to monitor energy dissipated in the TVS 123 .
[0035] FIG. 2 shows voltage and current during the lift mode. When the operator activates “Lift” at time “L”, the logic controller 108 closes the switches 103 and 102 . Current flows from the generator 101 to the magnet 150 . Current from the DC generator 101 is applied to the lifting magnet through the switches 103 and 102 as shown in FIG. 3 , and the current ramps to the lifting magnet rated current value. The operator ends “Lift” at time “D 1 ”, whereupon the circuit is configured shown in FIG. 4 , the voltage rises to the TVS breakdown value, and the current in the lifting magnet decays. When the current direction reverses in the DC generator (at time D 2 ), the circuit is as shown in FIG. 5 where the lifting magnet energy discharges into the DC generator. When the lifting magnet energy is released (at time D 3 ), current in the lifting magnet reaches zero and then starts to ramp in the reverse direction as shown in FIG. 6 . When the current value becomes equal to the “Drop current threshold” (at time D 4 ), the circuit is in the configuration shown in FIG. 7 , the voltage steps to TVS breakdown value, and the current in the lifting magnet decays. When the current direction reverses in the DC generator (at time D 5 ), the circuit is as shown in FIG. 8 , the lifting magnet energy discharges into the DC generator, and the current decays until substantially all lifting magnet energy is released (at time D 6 ).
[0036] FIG. 3 shows current in the system 100 during the “Lift” mode. During lift, the logic controller 108 keeps the switches 101 and 104 open (e.g., off), and closes (e.g., turns on) the switches 103 and 102 . Current flows from the positive terminal of the DC generator 101 through the switch 103 , through the lifting magnet 150 , through the switch 102 and back to the generator 101 . Rated current establishes in the lifting magnet 150 after a few seconds, based on the time constant of the circuit, which is primarily due to the inductance to resistance ratio (L/R) of the lifting magnet 150 .
[0037] FIG. 4 shows current in the system 100 during the “Lift” off mode. When operator needs to release the material being lifted by the magnet, the operator instructs the logic controller 108 to start the drop process. The drop process includes lift off ( FIG. 4 ), discharge ( FIG. 5 ), drop ( FIG. 6 ), drop off ( FIG. 7 ) and secondary discharge ( FIG. 8 ). During lift off, switches 103 and 102 are turned off and a few milliseconds later switches 101 and 104 are turned on. Due to the inductance of the generator, the generator current is still flowing in the same direction as it was flowing during “Lift”. Because the switches 103 and 102 are off, the generator current flows through the TVS 123 . Due to the inductance of the lifting magnet, the lifting magnet current is still flowing in the same direction as it was flowing during “Lift”. So, if for example, during “Lift”, a current of 100 Amps was flowing through the DC generator 101 and the lifting magnet 150 , at the time 103 and 102 turn off, a current of 200 amperes flows through the TVS 123 , with the DC generator 101 contributing for 100 amperes, and the lifting magnet 150 contributing for 100 amperes.
[0038] FIG. 5 shows current in the system 100 during the discharge mode. The lifting magnet 150 has a longer time constant than the DC generator 101 , so the direction of current will reverse in the DC generator 101 before it can reverse in the lifting magnet 150 . When the DC generator 101 allows current to reverse its direction, the lifting magnet current flows back into the DC generator 101 . The difference of potential V M2 -V M1 across the lifting magnet is positive. Therefore, the lifting magnet 150 acts as a source of energy, and energy from the lifting magnet is transferred from the lifting magnet 150 to the DC generator 101 .
[0039] FIG. 6 shows current in the system 100 during the “Drop” mode. During drop mode, switches 101 and 104 are closed. When there is insufficient energy left in the lifting magnet 150 to maintain the reverse current flow into the DC generator 101 , the DC generator 101 generates a “reverse” current in the lifting magnet 150 . Based on the time constant of the circuit, the reverse current gradually increases.
[0040] In one embodiment, the switches 101 and 104 are closed during the lift-off phase. Since the flyback diodes 114 and 111 are forward biased during the lift-off phase, the switches 101 , 104 need not to be forward biased (in other words, the switches 101 , 104 can be closed by the logic controller 108 but nevertheless not conducting current because they are reversed biased). Once the magnet 150 is discharged, the current through the magnet will reverse during the drop phase and thus the switches 101 , 104 will become forward biased.
[0041] FIG. 7 shows current in the system 100 during the “Drop” off mode. When the current measured by the current sensor 121 (and/or the current sensor 122 ) matches the “Drop current threshold”, the logic controller turns the switches 101 and 104 off. Due to the inductance of the generator 101 , the generator current is still flowing in the same direction as it was flowing during “Drop”. Because all of the switches 101 - 104 are off, generator current flows through the TVS 123 . Due to the inductance of the lifting magnet 150 , the lifting magnet current is still flowing in the same direction as it was flowing during “Drop”. If for example, during the “Drop” a “reverse” current of 20 Amps was flowing through the DC generator and the lifting magnet, at the time the switches 101 and 104 turn off, 40 amperes would flow in the TVS 123 , with the DC generator 101 contributing for 20 amperes, and the lifting magnet 150 contributing for 20 amperes.
[0042] FIG. 8 shows current in the system 100 during secondary discharge. The lifting magnet 150 has a longer time constant than the DC generator 101 , so the direction of current will reverse in the DC generator 101 before it can reverse in the lifting magnet 150 . When the DC generator 101 allows current to reverse its direction, the lifting magnet current flows back into the DC generator 101 . The difference of potential V M1 -V M2 across the lifting magnet is positive. Therefore the lifting magnet 150 acts as a source of energy, and energy is transferred from the lifting magnet 150 to the DC generator 101 . Then the “reverse” current into the generator 101 gradually decays to zero when all the energy left in the lifting magnet 150 is dissipated.
[0043] FIG. 9 shows current in the system 100 during an open circuit in the “Lift” mode. If during “Lift”, the DC generator 101 is accidentally disconnected, such as in the case of a loose connection or if the fuse 130 opens, the path for the lifting magnet current is through the circuit formed by the diodes 111 , 114 and the TVS 123 . In one embodiment, the TVS is not sized to absorb all the lifting magnet energy. The logic controller 108 measures the current in the TVS 123 by sensing a voltage across the resistor 124 . If excess current in the TVS 123 is detected, then the circuit switches into “Freewheel TVS protection” mode to protect the TVS 123 against overload.
[0044] FIG. 10 shows current in the system 100 during the “Freewheel TVS protection” mode after an open circuit in the “Lift” mode. In the “Freewheel TVS protection” mode, the switch 103 is closed and the diode 111 is forward biased, thus providing a loop for the current circulating in the lifting magnet 150 to maintain the same direction that it had during “Lift”.
[0045] FIG. 11 shows current in the system 100 during an open circuit in the “Drop” mode. If during “Drop”, the generator 101 is accidentally disconnected such as in the case of a loose connection or if the fuse 130 opens, the path for the lifting magnet current is through the circuit formed by the diodes 113 , 112 and the TVS 123 . In one embodiment, the TVS 123 is not sized to absorb all the lifting magnet energy. The logic controller 108 measures the current in the TVS 123 by sensing a voltage across the resistor 124 . If excessive current in the TVS 123 is detected, then the circuit switches into “Freewheel TVS protection” mode to protect the TVS 123 against overload.
[0046] FIG. 12 shows current in the system 100 during the Freewheel TVS protection mode after an open circuit in the “Drop” mode. In “Freewheel TVS protection” mode, the switch 101 is closed and the diode 113 is forward biased, thus providing a loop for the current circulating in the lifting magnet 150 to maintain the same direction that it had during “Drop”.
[0047] reewheel TVS protection mode is not polarity sensitive. When a TVS overload is detected, Freewheel TVS protection mode is activated by closing switches 101 and 103 to divert the current from the TVS. As described above, the switch 101 can be closed to form a loop with diode 113 , and the switch 103 can be closed to form a loop with diode 111 .
[0048] Logic controller 108 monitors currents passing through sensors 121 and 122 . If an unbalance occurs, then the logic controller 108 signals a ground fault alarm. In one embodiment, the logic controller 108 will turn off the switches 101 - 104 if an overload condition is detected.
[0049] FIG. 13 , consisting of FIGS. 13A-13E , is a schematic diagram of one example circuit embodiment for the logic controller. In FIG. 13 , a LIFT INPUT is received from a “Lift” user control (e.g., a such as, for example, a lift push button provided to the circuit of FIG. 13 via an opto-isolator). The “Lift” control initiates the “Lift” operation. After the “Lift” push button is released, circuit stays in “Lift”. A thermostat that senses the temperature of the one or more of the switches 101 - 104 (or a heat-sink for the switches 101 - 104 ) can be provided to a THERMOSTAT input shown in FIG. 13 . If the switches get too hot, the thermostat sends a signal to the THERMOSTAT input that prevents initiation of the next Lift operation, however, a lift currently in progress is not terminated (for safety reasons). A “cycle” control (e.g., push button and associated electronics) can be provided to a CYCLE INPUT. The “Cycle” control can be used to replace (or supplement) the lift and drop controls. Activating the cycle control (e.g., pressing the cycle button) causes the status of the Magnet Controller to cycle through “Lift”, then “Drop” and automatically to “OFF”, and then again to “Lift” etc. Basically U 301 A with its complemented output fed in its data input acts as a divider by 2. A POWER UP RESET line is temporary held ON when control power is applied (or after power has been cycled to reset a fault) to set the status of D Type Flip-Flop (latches) in the circuit. A DROP INPUT receives signals from a “Drop” control (e.g., a “Drop” push button and associated opto-isolator and electronics). The “Drop” push button terminates the “Lift” and initiates the “Drop”. After the “Drop” push button is released, the circuit finishes “Lift” and then automatically goes to “Off”. A NO CONTROL POWER input is configured to receive a signal indicating that the 24V DC power supply has fallen below 18V. A typical 24V to 15V voltage regulator needs at least 18V on its input to guarantee 15V output. So if control power supply is too low, to protect against unexpected behavior, the switches 101 - 104 are turned off when the NO CONTROL POWER signal is received. The “Drop” current can be adjusted by an optional potentiometer P 201 . An HE POS input receives current sensor signals from the current sensor 121 . An HE NEG input receives current sensor signals from the current sensor 122 . A SHORT CIRCUIT input is provided to receive a signal if an overload or short condition is detected. A connector CN 521 provides inputs from the TVS current sensor 124 . The circuit of FIG. 13 is configured to use a 0.1 ohm resistor as the TVS current sensor. If a TVS overload signal is received at the TVS input, the switches 101 and 103 are then turned on to protect 123 .
[0050] FIG. 13B shows “LIFT” and “DROP” outputs. The “LIFT” output is provided to drivers that control the switches 102 and 103 . The “DROP” output is provided to drivers that control the switches 101 and 104 . The “LIFT” output is activated to produce the lift function. The “DROP” output is activated to control the drop function.
[0051] It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrated embodiments and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributed thereof; furthermore, various omissions, substitutions and changes may be made without departing from the spirit of the inventions. The foregoing description of the embodiments is, therefore, to be considered in all respects as illustrative and not restrictive, with the scope of the invention being delineated by the appended claims and their equivalents. | A magnet controller supplied by a DC generator controls a lifting magnet. Four transistors, forming an H bridge, allow DC current to flow in both directions in the lifting magnet. During “Lift”, full voltage is applied to the lifting magnet. During “Drop”, reverse voltage is applied briefly to demagnetize the lifting magnet. At the end of the “Lift” and the “Drop”, most of the lifting magnet energy is returned to the DC generator. A transient voltage suppressor protects against voltage spike generated when current reverses in the generator. | 1 |
FIELD OF THE INVENTION
The present invention relates to a storage rack and to a system for loading and unloading said storage rack with pallets carrying articles to be stored and retrieved from said rack. More particularly, the invention concerns the rack of a concrete block curing kiln and associated loading and unloading equipment.
BACKGROUND OF THE INVENTION
In Applicants' co-pending patent application 08/354,258 filed Dec. 12, 1994 and entitled STORAGE RACK LOADING AND UNLOADING SYSTEM, now abandoned, the storage rack is composed of several bays disposed side by side and opening at the front face of the rack, each bay formed of a series of stacked tiers, each provided with a pair of horizontally arranged tracks extending from the front to the back of the rack and supported by posts or columns. The articles carrying pallets are accumulated in front of the rack with the pallets in end-to-end alignment normal to the face of the rack and in a number to have a combined length equal to approximately the depth of the bays; a pusher/puller system is suspended from a travelling crane to pick up the assembled and aligned pallets by means of Z-shaped pallet holding beams and to push the assembly of the Z beams and aligned article blocks carrying pallets into a selected tier of a selected bay with the pallets suspended from the tracks by the Z-beams. To unload, the assembly is pulled completely out of the rack outwardly of its front face. While this system is thought to be an important improvement over previously known systems, it is now believed that additional important improvements can be obtained by providing a storage rack which can be loaded and unloaded from the top by mechanical means without requiring direct human intervention contrary to the known top loaded and unloaded rack described in A. A. PAULY's U.S. Pat. No. 1,009,557 dated Nov. 21, 1911 entitled APPARATUS FOR CURING CEMENTITIOUS MATERIAL.
OBJECTS OF THE INVENTION
It is the general object of the present invention to provide a storage rack with an overhead loading and unloading system resulting in more flexibility in storing articles of variable standard height while reducing the dead space to a minimum.
Another object of the present invention is to provide a storage rack to be loaded and unloaded from the top and including a minimum of framework, the tracks, in accordance with the above defined storage rack, being completely eliminated.
Another object of the present invention resides in the provision of a loading and unloading system in which the pusher and puller system of the above noted co-pending Patent application is completely eliminated.
Another object of the present invention resides in the provision of a method for curing concrete blocks using a curing kiln in which said storage rack is used only for partial curing of the blocks, final curing being achieved in the kiln with the units formed by the blocks and their pallets directly stacked on top of one another after the blocks have achieved a compressive strength sufficient to support, for instance a stack of ten such units, thus the kiln's effective curing capacity can be maintained while reducing the amount of framework required to handle the concrete blocks.
Another object of the invention resides in the provision of a system of the character described in which the size of the building for housing the storage rack and the loading and unloading system can be considerably decreased with respect to the system of the above noted U.S. patent application.
SUMMARY OF THE INVENTION
The present invention is directed to the combination of a storage rack and of a loading and unloading system for pallet carrying articles to be stored and retrieved from said storage rack, said rack including vertical elongated wells arranged side by side in parallel rows and delimited by parallel rows of spaced columns, each well being of uniform width along its length and fully opened at the top, said system including crane means including a travelling bridge and a hoisting block and movable over and across said storage rack, said hoisting block operable to hoist or lower an article carrying pallet from and onto a support surface outside of said storage rack, move said pallet over said storage room in vertical register with any selected well and then lower or hoist said article carrying pallet down or up said well to or from a selected level and further including means carried by said hoisting block and actuated from said travelling bridge to lock and unlock said pallet within said well at said level.
The present invention is preferably directed to the combination of a storage rack and of a loading and unloading system for articles carrying pallets to be stored within and retrieved from said storage rack, said storage rack comprising a plurality of spaced columns arranged therein in parallel rows to form several open top elongated storage wells disposed side by side, the columns on each side of anyone well having a series of vertically spaced upwardly facing steps equally protruding from said columns towards the centre of said well, said steps forming sets of steps which are at the same level; said loading and unloading system comprising a pallet holder to carry a series of said pallets in end-to-end relation, said pallet holder consisting of a pair of Z beams disposable along opposite sides of said series of pallets, each Z beam of Z-shaped cross-section defining a lower inturned flange to extend under and support said series of pallets and an upper outturned flange, a crane including a hoisting block, motorized means to move said hoisting block over and across said wells and to stop said hoisting block above a selected well, means to lower and hoist said hoisting block between said columns of said selected well, a pair of hooks pivotally carried by and depending from said hoisting block, actuating means to pivot said hooks towards and away from each other between an opened and a closed position relative to said hoisting block, the upper outturned flange of said Z beams engageable by said hooks whereby said article carrying pallets can be suspended by said hooks through said Z beams, the assembly of said article carrying pallets, said Z beams, said hooks and said hoisting block clearing said steps when said hooks are in closed position so that said article carrying pallets can be hoisted or lowered through said well up from or down to a selected level, opening of said hooks from said closed position causing spreading apart of said outturned flanges of said pair of Z beams and allowing their transfer into engagement with a corresponding set of steps at said selected level.
Preferably, said lower inturned flange of said Z beams has a size to extend only under a side marginal portion of said pallets, and said hooks can pivot to a more opened position to cause said lower inturned flange to clear said side marginal portions of said pallets when the latter are supported on a support surface leaving said marginal portions exposed.
Preferably, said storage wells are of equal width and length and said series of steps are equally spaced along said columns, said Z beams having a length substantially equal to the length of said storage wells and each well is subdivided into equal size sub-wells of quadrangular cross-section and delimited by said columns located at the four corners of said sub-wells, are equally spaced longitudinally of said storage wells and form pairs of transversely aligned columns for each storage well, said hoisting block being subdivided into sub-blocks interconnected in end-to-end relationship, any one sub-block of a width and length to be hoisted and lowered between and guided by the columns delimiting a sub-well.
Preferably, the columns have an H-shaped cross-section defining a web and right angle flanges, said hoisting block carrying guiding wheels engageable with said flanges of said columns to guide said hoisting block during its hoisting and lowering movement within anyone storage well.
Preferably, the steps are formed by stamped, outwardly inclined portions of the column flange.
Preferably, the motorized means includes a travelling bridge movable over and across said wells, and further including first and second cable means extending between said hoisting block and said travelling bridge, said hoisting block including an outer frame and an inner frame guided for vertical movement with respect to each other, said outer and inner frames respectively carrying first and second cable engaging pulleys, said first and second cable means trained on said first and second cable engaging pulleys respectively, the upper end of each said hook pivoted to said outer and inner frames by pivots transversely spaced relative to both frames whereby selective hoisting movement of said outer and inner frames by first and second pulleys will cause pivoting of said hooks between said closed position and said opened position.
Preferably, a cam member extends along each hook and its upper end is pivoted to said hook, each cam member having a lower portion protruding downwardly from the lower end of said hook and engageable with the outside of a Z beam suspended from several said hooks, each cam member having a cam edge, and a cam follower carried by one of said frames and following said cam edge during pivoting movement of said hooks, whereby upon opening movement of said hooks and consequently of the outturned flanges of said Z beams, said inturned flanges of said Z beams are positively maintained by said lower portions of said cam members in supporting engagement with said series of pallets, and upon closing movement of said hooks said lower portions of said cam members positively push said Z beams inwardly towards said pallets causing said inturned lower flanges to come in supporting engagement with said series of pallets.
Preferably, each Z beam has a web formed of an upper section and of a lower section, both sections making an obtuse angle with respect to each other, said upper section terminated by said outturned flange and of a width sufficient to abut against two adjacent vertically spaced sets of steps when said outturned flange is hooked onto the upper one of said two sets of steps, to therefore maintain said lower section at a downwardly inwardly inclined position so that said pallets can be made of a size to clear said steps with a sufficient gap during their hoisting and lowering movement through said well and yet be positively maintained in stored position by the lower inturned flanges of said Z beams.
Preferably, a pair of rails are horizontally disposed at the top of said storage rack perpendicularly to the respective ends of said storage wells, said rails extending across and beyond one end of said storage rack, said travelling bridge rollable on and guided by said rails, said first and second cable means trained on pulleys carried by said travelling bridge, first power operated cable shortening means to shorten one of said first and second cable means relative to the other, cable pay-out and retrieving power operated means operating said first and second cable means to lower and hoist said hoisting block relative to said travelling bridge, third cable means and third power operated winch means to selectively move said travelling bridge across said wells to positions above any selected well and an outer position laterally of said one end of said storage rack, said cable shortening means, cable pay-out and retrieving means and winch means being located laterally outwardly of said one end of said storage rack.
Preferably, the travelling bridge has an inverted U-shape and said hoisting block has a size and shape such that, in its uppermost hoisted position, it completely nests within said travelling bridge to clear the top of said wells.
Preferably, vertical, elongated guiding members are carried by said travelling bridge and in vertical alignment with the columns of said selected well above which said hoisting block is stopped, and guide wheels carried by said hoisting block, engage only said guiding members when said hoisting block completely nests within said travelling bridge, engage both said guiding members and the columns of said selected well when said hoisting block is partially nested within said travelling bridge and engage only the columns of said selected well when said hoisting block is completely located within said selected well.
Preferably, there are further provided a vertically movable locking pin carried by said travelling bridge at each end thereof, a pulley attached to each locking pin, fourth cable means extending along both rails trained on each pulley and anchored to a fixed point at one end and fourth cable tightening means attached to the other end of said fourth cable means to selectively tighten said fourth cable means with the consequent raising of said locking pin or release of said fourth cable means with the consequent lowering of said locking pin, and abutment means at each well and along each rail to engage said locking pins only when the latter are lowered and to consequently positively position said travelling bridge in vertical alignment with said selected well.
Preferably, the third cable means include a cable loop associated with and attached to each end of said travelling ridge, said winch means including a winch for each cable loop, each cable loop including a pay-out run and a return run extending between said winch and said travelling bridge and means to align said travelling bridge with said wells including cable shortening powered means for at least one cable loop to alternately shorten and lengthen said pay-out run and simultaneously alternately lengthen and shorten said return run in equal amount.
Preferably, each winch includes a drive shaft of polygonal cross-section, a winch drum non-rotatably mounted and axially shiftable on said drive shaft, said drum having a helicoidal groove receiving a few turns of the loop cable driven by said drum and the two drive shafts are driven by a common motor.
Preferably, each well is subdivided into equal size sub-wells of rectangular cross-section and delimited by said columns being located at the four corners of said sub-wells, said hoisting block being subdivided into as many sub-blocks as there are sub-wells, said sub-blocks interconnected in end-to-end relationship, any one sub-block being rectangular and of a width and length to be hoisted and lowered between and guided by the columns delimiting a sub-well, said first and second cable means including, for each sub-block, a looped cable anchored to a stationary station at the opposite end of said rack relative to said one end of said rack and a counter weight suspended by said looped cables and biasing said interconnected sub-blocks to an uppermost position clearing the top of said wells when said sub-blocks are not loaded with article carrying pallets.
Preferably, levelling means serve to level the assembly of interconnected sub-blocks.
In a specific application of the present invention, the storage rack is located in an enclosure having walls, a roof and heating means to form a concrete block curing kiln, said roof spaced above said walls, one of said walls having an opening to access the top of said rack, a door for said opening, said articles being green concrete blocks to be cured in said kiln with the blocks and pallets carrying the same stored in said wells with the green blocks on one set of aligned pallets spaced below an adjacent set of aligned green block carrying pallets.
There may be provided a storage floor area within said kiln, said motorized means capable of moving said hoisting block over said floor area as well as over and across said wells, said crane capable of successively loading said wells of said kiln with green blocks carrying pallets and, after partial curing of said blocks within said rack, of successively unloading the partially cured blocks together with their supporting pallets from a selected well and directly stacking said blocks and their pallets onto said floor area and retrieving said Z beams to form stacks of blocks with intervening pallets, the block of these stacks being left to fully cure in the kiln.
The present invention is also directed to a method for curing concrete blocks comprising the steps of:
a) positioning green blocks on a predetermined number of separate pallets, aligning said pallets and fitting a pair of support beams to opposite sides of said aligned pallets to form a first assembly of a given length;
b) hoisting said first assembly to a level higher than the top of a rack located in a concrete block curing kiln and forming vertical elongated wells of a length and width slightly greater than the length and width of said assembly, said wells accessible from the top end and disposed side by side, each well delimited by parallel rows of columns carrying vertically spaced steps protruding from said column towards the centre of said wells, the steps forming sets of steps at the same level;
c) horizontally moving said first assembly to a position above a selected well and in longitudinal register therewith;
d) lowering said first assembly through said selected well and hooking the support beams of said first assembly to a lower set of steps in a stored position;
e) repeating steps a) to c) with a second assembly substantially identical to said first assembly;
f) lowering said second assembly through said selected well and hooking the support beams of said second assembly to a higher set of steps, the two assemblies being vertically spaced from each other; and
g) allowing the green blocks to cure in said kiln.
Preferably, after partial curing of said green blocks in said second assembly is hoisted out of said well and lowered directly onto a support surface inside of said kiln, said support beams of said second assembly are retrieved, said first assembly is hoisted out of said well and lowered onto the second assembly until the pallets of said first assembly rest directly on the partially cured concrete blocks of said second assembly to form a stack, the support beams of said first assembly are retrieved from the pallets of said first assembly and the stack of concrete blocks are left to fully cure in said kiln.
It has been found that a stack of ten such assemblies of partially cured concrete blocks can be formed without block damage.
BRIEF DESCRIPTION OF THE DRAWINGS
In the annexed drawings, FIG. 1 is a top plan view of the general arrangement of the system in accordance with the invention, the kiln shown without its roof;
FIG. 2 is a diagrammatic elevation of the kiln, the storage rack within the kiln and schematic cross-section of the green block and dry block conveyors and of the Z beam accumulator;
FIG. 3 is a partial top plan view of the hoisting block shown in engagement with the columns of the well, the columns shown in cross-section;
FIG. 4 is a cross-section of the hoisting block showing one embodiment of the hooks, in the process of transferring the Z beams to the steps of the columns of the well, this Figure also showing how the Z beam can support pallets carrying blocks of different heights;
FIGS. 5 and 6 are partial sections taken along line 5--5 of FIG. 3, showing two different pivoted positions of a second preferred embodiment of the hooks;
FIG. 7 is a cross-section of one end of the travelling bridge and of one rail supporting the same;
FIG. 8 is an end view of the travelling bridge taken along line 8--8 of FIG. 7;
FIG. 9 is a cross-section of the travelling bridge showing the hoisting block in the process of being guided from within the travelling bridge to within a well of the storage rack;.
FIG. 10 is a perspective view of half of the actuating arrangement for controlling the travelling bridge, the hoisting block and its hooks, the other half being similar;
FIG. 11 is a top plan view of half of the travelling bridge with its cable and pulley arrangement and of the actuating arrangement located on the outside of the kiln;
FIG. 12 is an elevation of one half of the actuating arrangement; and
FIG. 13 is a side elevation of the Z beam transferring mechanism which is part of the Z beam accumulator.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIGS. 1 and 2, there is shown a concrete block curing kiln 2 which is delimited by walls 4, a floor 6, a roof 8. One end wall 4a has a door opening 10 adjacent the roof 8 which is closable by a vertically movable door 12 which is moved between a closed, raised position shown in dotted line and an open, lowered position shown in full line. The door is counter-balanced to closed fail safe, position by a counter-weight arrangement (not shown).
FIGS. 1 and 2 also show a green block conveyor 14 coming from a concrete block moulding machine (not shown), a dry block conveyor 18 for receiving the blocks which have been cured in the kiln and a Z beam accumulator 20 mounted underneath the dry block conveyor 18.
A storage rack is located within kiln 2. This rack simply consists of a series of columns 24 arranged in parallel rows and right angle cross rows, each column having a foot plate 26 which is fixed to the floor 6 by means of a bolt and nut arrangement 28 (see also FIG. 4) which enables levelling and inclining of each column. Each column has an H shape being preferably made of two oppositely directed channels (see FIG. 3) secured together and defining a web 30 and flanges 32. A series of ears 34 are stamped out of flanges 32 on opposite sides of the column, these ears 34 form equally vertically spaced upwardly directed steps.
Referring to FIGS. 1, 2 and 4, freshly moulded concrete blocks C coming from the concrete block moulding machine are carried on the conventional pallets P, which normally consist of a thin steel plate, these green blocks must be stored within the storage rack 22 for curing kiln 2. For this purpose, the blocks carrying pallets P are accumulated in contiguous relation on the portion 14a of the green block conveyor 14, this portion being parallel to and adjacent the door opening 10 as seen in FIG. 1. A pair of Z beams 36 are used to engage in the group of accumulated pallets P and to carry the same into the kiln and to suspend the pallets and blocks on the steps 34 of the selected rows of columns and at a selected level to be cured. Z beams are also used to remove the pallets with the cured blocks C and transfer them to the conveyor section 18a of dry block conveyor 18.
As more particularly shown in FIG. 4, each Z beam 36 has a length about equal to that of conveyor section 14a and such as to extend across the entire length of a well 37 which extends across the kiln parallel to the conveyor sections 14a and 18a therebeing several wells disposed side by side, each delimited by two parallel rows of columns with, for the intermediate wells, one row being common to two adjacent wells. Each well 37 is in turn divided into, for instance, four sub-wells (as shown in FIG. 1), each sub-well 37a being of rectangular shape and delimited by four columns 24 (as shown in FIG. 3). For the intermediate wells, columns 24 are common to two adjacent sub-wells.
Each Z beam 36 defines a web with an upper outturned flange 40 and a lower inturned flange 42 (see FIGS. 4 and 13). Moreover, the upper section 44 of the web makes an obtuse angle with respect to the lower section 46 of the web. Upper web section 44 has a width slightly greater than the distance between two consecutive steps 34 of one column so that in pallets suspending position (shown in FIG. 4) with outturned flange 40 engaging a series of steps at the same level, the web upper section 44 is maintained substantially vertical since it abuts against the steps at the next lower level. In this manner, the lower inturned flanges 42 of the Z beams 36 which engage under the sides of the pallets P are maintained sufficiently away from steps 34. It follows that the spacing between the columns can be selected so as to obtain a good clearance between the sides of the pallets P and the columns, and consequently of the Z beams when the assembly of the Z beams, pallets and concrete blocks are being lowered or hoisted within a selected well 37.
A pair of parallel rails 48 extends within the kiln to and outside of the same at the level of the top of the columns 24 and perpendicularly to wells 37 and to the conveyor sections 14a and 18a. Rails 48 are interrupted at the door opening 10 for the passage of the door. However, this door has rail sections 50 on the top thereof to bridge the interruption in the rails 48 when the door is in lowered position, giving access to the kiln. A crane is used to transport the assembly of the Z beams 36 with the concrete block carrying pallets P from the green block conveyor 14 into the storage rack 22 and after curing from the kiln onto the dry block conveyor 18. The crane comprises a travelling bridge 52 and a hoisting block 54 suspended from the travelling bridge. Block 54 has a length to extend through an entire well 37, across nearly the entire distance between rails 48.
As shown in FIGS. 7 to 9, travelling bridge 52 is of generally inverted U shape and is provided at its ends with wheels 56 which rolls on rails 48. Travelling bridge is guided on the rails 48 by side shoes 58 slidably engaging beams 60 supporting the rails 48. Stops 62 are fixed to beam 60 at predetermined positions along the rails 48 to be engaged by a pair of locking pins 64 vertically movable and guided by the frame work of the travelling bridge 52 to take a lowered position as shown in full line in FIG. 8 abutting the stops 62 to positively lock the travelling bridge 52 in vertical alignment with a selected well 37. The locking pins 64 carry pulleys 66 at their upper ends on which a cable 68 is trained. Upon tightening cable 68, pulleys 66 raise the associated locking pin 64 to clear the stops 62 to enable movement of the travelling bridge. The latter can move along rails 48 to be positioned above any selected well 37 and to positions outside kiln above conveyors 14 and 18. The travelling bridge can also move within the kiln to positions above secondary wells 70 (as shown in FIG. 2) which will be described later on.
As shown in FIG. 10, both ends of the travelling bridge 52 can be positively stopped at any one of the selected positions by the locking pins 64 and stops 62. The cable 68 at each end of the travelling bridge is anchored to a fixed point at 72 at the remote end of the kiln while its other end is attached to the piston of a hydraulic cylinder 74 which serves to tighten cable 68 and thus raise pulleys 66 and locking pins 64. Pulleys 66 together with the pulleys 76 carried by the travelling bridge and on which cable 68 is trained, allow the movement of the travelling bridge along rails 48.
Hoisting block 54 consists of several sub-hoisting blocks 54a rigidly maintained in alignment by links 78 (as shown in FIG. 3). Each sub-block 54a is of a generally rectangular shape and of a size to fit within a sub-well 37a as delimited by four columns 24 arranged at the four corners of the sub-well. Each sub-block 54a includes an outer frame 80 and an inner frame 82, the latter mounted within the former. Links 78 interconnect the four outer frames 80. Outer and inner frames 80 and 82 can move vertically, one relative to the other. The outer frame 80 has, at its four corners, downwardly depending guiding members 84 reinforced by horizontal braces 84a and provided at their upper and lower ends with guiding wheels 86. These guiding wheels 86 engage the flanges 32 of the columns 24 when the hoisting block is being raised or lowered within a sub-well delimited by said columns.
Also, the guiding wheels 86 come in guiding engagement with vertical guiding members 88 carried by the travelling bridge 52. Each sub-block 54a is therefore retained in bridge 52 when completely nested therein and is continuously guided while being transferred from the travelling bridge to the columns, and vice versa, since guiding members 88 form upward extensions of the columns.
Inner frame 82 carries an inner pulley 90 while outer frame 80 carries a pair of outer pulleys 92, pulleys 90 and 92 being disposed across the middle of the sub-block 54a (see FIGS. 3 and 4). Inner cable 94 and outer cable 96, trained respectively on inner pulley 90 and the two outer pulleys 92, serve to selectively raise the inner frame with respect to the outer frame and vice versa. These two cables also suspend each sub-block 54a from the travelling bridge and serve to raise or lower hoisting block 54 as will be described later on. Referring to FIG. 3, it is seen that the inner frame 82, when raised relative to outer frame 80, attains a top limit position in which it stops against an adjustable abutment member 81, secured to outer frame 80 and which is preferably adjustable. The two frames are guided for relative vertical movement. Abutments (not shown) limit the downward movement of inner frame 82 to a lower limit position. Each sub-block 54a carries, at its two ends, a pair of transversely disposed and inwardly facing hooks 98 which clear the transversely aligned columns 14 inwardly thereof. A preferred embodiment of the hooks is shown at 98a in FIGS. 5 and 6.
Each hook 98 or 98a is of generally triangular shape carrying, at its lower end, a hooking plate 100 to engage the outturned upper flange 40 of the Z beam 36; referring to FIG. 4, the upper portion of each hook 98 is pivoted at 102 to outer frame 80 and at 104 to inner frame 82. Pivots 102, 104 are transversely aligned with respect to the sub-block 54a. Pivot 104 has a sliding fit on inner frame 82. Lengthening of the inner cable 94 with respect to the outer cable 96 causes lowering of the inner frame 82 with respect to the outer frame 80 and consequently closing movement of the facing hooks of a given pair to a closed position shown at 106 in FIG. 4 in which the hooks and consequently the Z beams hooked onto the same and the assembly of the pallets P and blocks C can clear the steps 34 protruding inwardly within the sub-wells 37a. It follows that the hoisting block 54 consisting of several, for instance four interconnected sub-blocks 54a, can raise and lower the assembly of the Z beams, pallets and concrete blocks within a selected well. The load is thus mainly supported by two outer pulleys 92 when the hoist is loaded with blocks C.
Upon shortening of the inner cable 94, the load on the sub-block is sufficiently transferred on the inner pulley 90 to cause raising movement of the outer frame 80 relative to the inner frame 82. As a consequence, the hooks 98 can take an intermediate opened position bringing the outturned upper flange 40 of the Z beams 36 in vertical alignment with the steps 34 so as to enable transfer of these Z beams onto the steps (position 108, FIG. 4) upon lowering movement of the hoisting block. Upon further opening of the hooks 98 to clear Z beam upper flanges 40, the hoisting block can be raised and retreived from well 37.
Hooks 98, when fully opened, can suspend Z beams 36 with their lower inturned flanges 32 clearing the sides of the pallets P, to permit pallet pick up from the green block conveyor section 14a and pallet release on dry block conveyor section 18a.
When picking up pallets or discharging the same onto rest surface, it should be noted that the rest surface must so support the pallets as to leave exposed the sides of the pallets that the Z beams can engage under these sides.
Each hook 98 is provided with a cam member 110 which serves to positively maintain the Z beams in engagement with the pallets P when the upper flange of the Z beams are being transferred onto the inwardly facing steps 34 of the columns 24 of a selected well. Each cam member is elongated and its upper end is pivoted to the respective hook 106 at 112 at a position below the pivots 102, 104. Cam member 110 has a lower end provided with a guide wheel 114 which is disposed below the lower end of the hook, namely below the hooking plate 100 so as to engage the central portion of the Z beam. Cam member 110 has an external cam edge 116 downwardly terminated by cavity 118. A cam follower 120 carried by the outer frame 80 engages cam edge 116 and causes the cam member 110 to positively maintain the lower inturned flange 42 into engagement with the underside of the pallet P during opening of the hooks 98 and transfer of the Z beams to the position 108 in FIG. 4. This Figure also shows that blocks C of different heights can be stored in the same well 37, to be cured.
FIGS. 5 and 6 show the preferred embodiment of the arrangement of the hooks and cam members identified by a hook 98a, a cam member 110a pivoted at 112a to hook 98a and a cam follower 120a carried by outer frame 80. In these Figures, the position of the pivots 102a and 104a and of cam follower 120a are as in the embodiment of FIG. 4, since pivots 102a and 104a are shown carried by the outer frame 80a and inner frame 82a respectively. Cam edge 116a of the cam member 110a now faces inwardly towards the centre of the well instead of outwardly as in FIG. 4. Cam follower 120a is carried by the inner frame instead of the outer frame. The hook 98a and cam member 110a shown in FIGS. 5 and 6 are preferred but outer pivot 102a and cam follower should be carried by inner frame 82 and inner pivot 104a should be carried by outer frame 80 as in FIG. 4 and for the same reason that is to support the load of blocks by the two outer pulleys, the hooks being then in closed position.
FIG. 5 shows the hook and cam in an intermediate open position similar to position 108 for transfer of the Z beam onto or from steps 34 while FIG. 6 shows the position of the hook, cam and Z beam assembly in a fully open limit position clearing the side edge of the pallets to pick up or discharge the same from or onto a rest surface as above noted.
FIGS. 10, 11 and 12 show the cables and the actuating system for moving the travelling bridge 52 along the rails 48, for locking the same above any well 37 or 70 and conveyors 14a or 18a and for raising and lowering the assembly of the sub-blocks 54a including the above noted cable means for opening and closing the hooks 98 or 98a. Due to the fact that the crane must enter the kiln which has a humid and hot atmosphere, the above noted movements are in accordance with an important feature of the invention controlled from the outside of the kiln through cable means and through driving means located and carried by a frame work 122 fixedly mounted on the floor of the plant on the outside of the conveyors 14 and 18 as shown in FIG. 1.
Travelling bridge 52 is moved along rails 48 by a cable and drive arrangement for each end of the travelling bridge. A cable 124 is attached at its ends 126 to the travelling bridge, is trained on pulleys 128 anchored at the remote end of the kiln, is trained on a pair of top pulleys 129 and on two pairs of pulleys 130 carried by the frame work 122 and is wound several turns on a winch drum 132 rotatably driven by a driving shaft 134 of polygonal cross-section on which the drum is axially movable. single electric motor 136 actuates through a gear box 138, the two drive shafts 134, one for each end of the travelling bridge, through the transmission shafts 140.
There are further provided means to align the travelling bridge with the wells 37, the two runs of the cable loop formed by the cable 124 are trained on the opposite sides of a pair of pulleys 142 mounted between pulleys 130 on a common frame 144, the horizontal position of which can be adjusted by a double acting hydraulic cylinder 146. Operation of cylinder 146 causes shortening of the pay-out run of cable 124 and simultaneous corresponding lengthening of the return run of said cable. Such a system can be provided at one end only of the travelling bridge.
As previously noted, the cables 94, 96 which are trained on the pulleys 90, 92 carried by the respective hoisting sub-blocks 54a serve to open and close the hooks and also to lower and raise the hoisting block. Cables 94, 96 are trained on pulleys 148 carried by the travelling bridge, and are anchored at 150 to the remote end of the kiln. Their other sections are trained on pulleys 152 carried by frame work 122, then on pulleys 154 carried by a beam 136 on which is mounted a counter-weight 158. The two cables are trained on a double pulley 160 horizontally movable and adjustable by a hydraulic cylinder 162. In the example shown, there are four sub-blocks 54a and it is seen that the same cables 94, 96 are common to two sub-blocks. The same system is repeated for the remaining two sub-blocks. It will be understood that by adjusting the position of the double pulley 160 at each pair of sub-blocks 54a, the hoisting block 54 can be levelled so that the hooks 98 or 98a over the entire length of the hoisting block will be at the appropriate level with respect to the same level steps along the length of the wells.
Adjusting of the position of the double pulley 160 at each end can be required depending on the uneven loading of the hoisting block and consequently of the uneven elongation of the cables 94, 96. Cable elongation is measured by load cells 164 mounted on each cable 94, 96 and the measurement made by the load cell serves to adjust the position of the hydraulic cylinders 162.
The hooks 98 or 98a can be open or closed by shifting the longitudinal position of inner cable 94 with respect to outer cable 96. This is done by training cable 94 on a vertically movable pulley 166 actuated by hydraulic cylinder 168 carried by frame work 132. Pulley 166 is disposed between a pair pulleys 170 carried by frame work 122. The counter-weight 158 is made heavier than the hoisting block 54 and its load so as to automatically raise the same to their upper limit position entirely nested within the travelling bridge 52. To lower the hoisting block and its load, an electric motor 172 drives a shaft 174 through a speed reducer 176. Shaft 174 drives vertically mounted sprocket chains 178 attached to the counter-weight carrying beam 156.
The Z beam accumulator 20 is shown in FIG. 2 and in FIG. 13. The Z beams 36 are stacked between two spaced, vertical guide rails 180 in vertical register with the respective sides of the pallets P deposited on the dry block conveyor section 18a. As shown in FIG. 13, the edge of the outturned upper flange 40 of each Z beam 36 is exposed between the guide rails; therefore the head 182 of the piston of an inclined ram 184 can engage the edge of the upper flange 40 and push it and retain it against a holder 186 carried by a bracket 188 on which ram 184 is mounted. Bracket 188 is pivoted about a horizontal axis 190 on a frame work 192 vertically movable alongside the guide rails 80 by means not shown. Frame 192 carries a ram 194 which serves to rotate bracket 188 above pivot 190. Adjustment of the bolt and nut 196 serves to adjust the position of Z beam 36 away from or towards the pallet P. Inward pivoting of the brackets 188 positively releases the Z beams from engagement with the hooks 98 or 98a carried by the hoisting block. After the hoisting block has moved away, the brackets 188 are pivoted to the upright position shown in FIG. 13 and the Z beams still retained by the inclined rams 184 within holders 186 can be positively lowered between the guide rails 180 and brought to a stacked position. The reverse operation is shown in FIG. 13, wherein the topmost Z beam is raised and its inturned flange caused to positively engage the underside of the pallets P in a position to be picked up by hooks 98 of the hoisting block.
Referring to FIG. 2, additional wells 70 may be provided alongside wells 37, wells 70 defined by columns 198 similar to columns 24 but without any steps 34. The travelling bridge 52 can be stopped in register with any well 70 and the hoisting block caused to lower a set of concrete blocks carrying pallets P by means of the Z beams 36, the hoisting block being guided by the columns 198. In this manner, pallets P carrying concrete blocks C which are not fully cured can be directly stacked onto another group of uncured blocks C to complete the curing of the concrete blocks.
The system of the invention operates as follows: at the start of the operation, no pallets P are on the dry block conveyor section 18a. Therefore a pair of Z beams 36 can be elevated to the level of the conveyor section 18a by the rams 84 and holders 86 to be picked up by the hooks 98 or 98a of the hoisting block 54. Travelling bridge 52 is moved over the green block conveyor and the hoisting block 54 together with the Z beams are lowered and the hooks 98 cause the Z beams to engage under the series of green block carrying pallets assembled at said station. The hoisting block together with the assembly of the two Z beams and green blocks carrying pallets is raised and nested within the travelling bridge. Door 12 is opened and the travelling bridge is moved on rails 48 and stopped over a selected well 37 (as shown in FIG. 2); the hoisting block with its load is lowered being guided by columns 24. During the lowering movement, the hooks are fully closed so that the Z beams clear the column steps 34. The hoisting block is stopped at a precise selected level so that the upper flanges 40 of the Z beams are just above the selected steps where the Z beams are to be suspended. The hooks 98 or 98a are opened to their intermediate position and then hoisting block 54 is slightly lowered to cause transfer of the Z beams from the hooks to the steps 34. The hoisting block is then lowered, the hooks are fully open to clear the upper flanges 40 of the beam 36 and the hoisting block is moved to its uppermost position, fully nested within the travelling bridge 52 which can then repeat the cycle by first picking up another pair of Z beams from the Z beam accumulator 20. Each well 37 is loaded starting from the lowermost level as shown in FIG. 2.
Preferably, after partial curing of the concrete blocks, they are transferred to stacked position between columns 198 to complete their curing. After full curing, the blocks are removed from the kiln and transferred onto dry block conveyor section 18a while the Z beams are stacked into the Z beam accumulator. The conveyor 18 moves the dry blocks to a shipping station. | A storage rack is loaded and unloaded from the top with pallets carrying articles to be stored in and retrieved from the rack. The rack consists of a series of spaced columns arranged in parallel rows defining wells accessible from the top; the columns have vertically spaced, upwardly facing sets of steps protruding to an equal extent towards the centre of the wells. A crane is horizontally movable over the rack and stoppable above a selected well; it has a hoisting block which can be lowered between and guided by the columns of the selected well; a pair of hooks are pivoted to the hoisting block for movement towards and away from each other between opened and closed position; a pair of Z-shaped pallet holding beams adapted to carry a series of pallets aligned in end to end relation are suspended from the hooks and clear the steps when in closed position. When the desired set of steps is reached, the hooks are opened causing spreading apart of the top portion of the Z beams to allow their hooking unto these steps. The reverse operation is effected for unloading. The hooks can handle the Z beams to pick up the aligned pallets from and deposit them onto a supporting surface. The system is particularly designed for loading green concrete blocks into and unloading cured concrete blocks from a curing kiln housing the rack. Preferably, the green blocks are left in the stored position between the columns of the kiln just to attain sufficient compressive strength; they are then unloaded and directly stacked on the floor beside the rack within the kiln with the intermediary only of the pallets for completion of the curing process in the kiln; thus the number of columns and Z beams can be decreased without reducing the effective curing capacity of the kiln. Also, the provision of a Z beams accumulating device is no longer required. | 5 |
RELATED APPLICATIONS
[0001] This application claims priority to U.S. Patent Application Ser. No. 62/186,787, filed Jun. 30, 2015, the entirety of which is included in this application by this reference.
BACKGROUND OF THE INVENTION
[0002] The present invention relates generally to animal feed supplements and, more specifically, to active ingredients, including metal butyric acid salts, micro-encapsulated in a three-dimensional matrix of modified fat to form a granule or beadlet that provides for controlled and sustained release of the metal butyric acid salts upon ingestion by an animal.
[0003] The efficacy and adsorption of a bioactive molecule in the digestive system is dependent on many different factors and properties of the molecule. To obtain the highest level of efficacy from the least amount of active ingredient in a formulation it is important to deliver the active molecules to the desired location in the digestive system over a specified period of time so as to provide the active ingredient through a timed and controlled release mechanism. As an energy source, butyric acid can be taken up by the cells lining the gastrointestinal tract and used directly for energy. When butyric acid is used as a feed additive for production animals, it is quickly adsorbed and metabolized by the epithelial cells in the upper part of the digestive system, including the esophagus and stomach, and very little makes it to the small intestine and none of it can be utilized by the hind gut. Encapsulation can aid in the delivery of metal butyric acid salts to the small intestine where it has the most benefit to the animal. One common way of encapsulating metal butyric acid salts and other feed ingredients for sustained release is to embed the active ingredient in a solid fat matrix. The release rate of the active ingredient from the encapsulating material can vary, depending on the ingredient being encapsulated, the properties of the fat that is being used for the encapsulation, the 3D structure of the final encapsulated matrix, and the encapsulation processing conditions.
[0004] Zinc is an essential trace mineral that is necessary for the normal growth and performance of animals and human beings. Zinc has been shown to either increase the catalytic activity or contribute to structural stability, for more than 300 enzymes. Zinc is essential for calcification of the bone and for normal functioning of many hormones including thyroid and insulin. In simple terms, zinc seems to affect most of the biological functions either directly or indirectly. Apart from these basic functions recent studies indicate that zinc has the potential to influence immune function and also has beneficial effects towards intestinal health. Zinc is usually supplemented as zinc sulfate in animal diets but other forms of zinc is also available including zinc propionate, zinc oxide and zinc-amino acid combinations. Beneficial effects of these alternative combinations of zinc are inconclusive.
SUMMARY OF THE INVENTION
[0005] The present invention includes the encapsulation or coating of metal butyric acid salts, namely zinc, sodium, potassium, calcium, magnesium, iron, copper, chromium, manganese, or any other minerals in a modified fat matrix to create a spherical granule (approximately 0.1 to 2.0 mm in diameter and more optimally 0.5 to 1.2 mm in diameter). The granules have an internal three-dimensional (3D) structure consisting of channels originating from the interior of the granules and terminating at the granule surface which allows for a controlled and sustained release of the active ingredient through the dissolution of the porous structure. The active ingredient present in the granules may be at 1 to 70 wt %.
[0006] The present invention is directed to the use of a group of compounds/reagents for controlling the release of feed additive, nutritional, and/or pharmaceutical ingredients from hydrogenated vegetable oil (HVO), including preferably hydrogenated palm oil (HPO), or other high melting fat or wax micro bead encapsulations generated with spray freeze technology or other similar technologies. Due to the chemical property of the active ingredients and unique characteristics of gut physiology for humans and other animals, targeted delivery and controlled release of the active ingredients is required for optimal efficacy. In poultry for example, the retention time of feed in the gut is relatively short and there is a need for rapid or faster release of the active ingredient to the gut from the encapsulation. In a bovine (ruminant), on the other hand, a slower release is required to allow for the targeted delivery of the active ingredient in the hindgut. In addition, due to the high acid level in the stomach, active ingredients may have to be protected from degradation to be released in the small intestine. Active ingredients have to be released at the right time and at the right location to be efficacious. There have been reports and practices of using HPO or high melting fat for encapsulation of active ingredients, but there have been no reports of methodologies to modify the characteristics of the fat matrix to control the release of actives with this encapsulation system. In the current invention propylene glycol, tween-20, polyethylene glycol, water, aqueous salt solutions, aqueous potassium hydroxide solution, and other polar compounds that are liquid under ambient temperatures and polar powder compounds, such as amino acids, salts and the like, that do not mix well with fat, were used at different concentrations to either increase or decrease the release of active ingredients from encapsulation. When these compounds were included one at a time or in combination, the release of active ingredients from the encapsulation beads was modified. The more modifiers included, the faster the release. The lower the amount of modifiers included, the slower the release. This was demonstrated with ZBA (the zinc salt of butyric acid in a molar ratio of 1:2) as the encapsulated active ingredient but would apply to other feed additives, nutritional and pharmaceutical active ingredients as well.
[0007] In a preferred embodiment, the active ingredient is ZBA containing zinc and butyric acid, a short chain fatty acid with many biological functions in the gastrointestinal tract of animals. The present invention improves the release of ZBA in animals, as shown in the improved growth of animals and the improved bioavailability of the butyric acid in the small intestine.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is a chart of the effect of propylene glycol concentration on dissolution as indicated by butyric acid released.
[0009] FIGS. 2A and 2B are photographs showing a cross section of granules from micro-channel test; panel A shows an unmodified granule in red dye solution overnight before cut open, panel B shows a modified, PG-treated granule in red dye solution overnight before cut open.
[0010] FIG. 3 is a chart of feed conversion at 28 days for the treatments with different formulations of ZBA encapsulation granules.
[0011] FIG. 4 is a chart of the butyric acid levels in the ileal contents of birds grown to 28 days.
[0012] FIG. 5 is a chart of the butyric acid levels in the excreta of birds grown to 28 days.
DESCRIPTION OF THE INVENTION
[0013] The present invention includes a method of forming a granule having an internal three-dimensional framework of channels to control the rate of release of an active ingredient from the granule. The method includes melting a vegetable oil, mixing into the melted vegetable oil a selected amount of at least one modifier and a selected amount of at least one active ingredient to form a melt composition, forming droplets of the melt composition and cooling the droplets to form a granule having an internal three-dimensional framework of channels. The modifiers are selected from compositions including but not limited to glycerine, Tween 20, Tween 80, propylene glycol, sodium stearate, lecithin, ionic and non-ionic surfactants, potash, aqueous potash and polyethylene glycol.
[0014] In preferred embodiments of the present invention, the selected amount of total modifiers is between 0.1 wt % and 20 wt % and all values between such limits, including, for example, without limitation or exception, the selected amount of total modifiers may be 0.2 wt %, 0.69 wt %, 3.47 wt %, 12.4 wt % and 19.99% . Stated another way, in preferred embodiments of the invention, the modifiers can take any value “ab.cd” wt % wherein a is selected from the numerals 0,1 and 2, and b, c and d are each individually selected from the numerals 0, 1, 2, 3, 4, 5, 6, 7, 8 and 9, with the exception that c cannot be less than 1 if a, b and d are all 0 and b, c and d are all 0 if a is 2.
[0015] In preferred embodiments of the present invention, the selected amount of total active ingredients is between 1 wt % and 70 wt % and all values between such limits, including, for example, without limitation or exception, the selected amount of total modifiers may be 2 wt %, 13.45 wt %, 55.5 wt %, 62.11 wt % and 69.9% . Stated another way, in preferred embodiments of the invention, the modifiers can take any value “ab.cd” wt % wherein a is selected from the numerals 0, 1, 2, 3, 4, 5, 6 and 7, and b, c and d are each individually selected from the numerals 0, 1, 2, 3, 4, 5, 6, 7, 8 and 9, with the exception that c cannot be less than 1 if a, b and d are all 0 and b, c and d are all 0 if a is 7.
EXAMPLE 1
[0016] Modifier screening. Compounds that were tested as potential modifiers of a fat matrix to obtain a self-supporting 3D-structure suitable for the controlled release of ZBA are listed in Table 1. These compounds were individually formulated at specific level with the hydrogenated vegetable oil and ZBA to generate encapsulated prototypes. The granules were formed by heating and stirring the composition until it melted and then applying the composition onto a spinning disc assembly. The spinning disc generates the droplets within a chamber flooded with a cloud of liquid nitrogen, resulting in a solidified droplet that was collected at the bottom of the chamber. Granules ranged from 0.1 mm to 2 mm diameter were collected. Prototypes with different formulations were then tested for butyric acid release in a shaker bath dissolution assay. Based on dissolution, the modifier that allowed for the formation of granules having suitable size, integrity, and shelf life while also provided for controlled and sustained release was propylene glycol, at a concentrations ranging from 1% to 20% in the final formula.
[0000]
TABLE 1
Formulations designed to screen for modifiers.
Modifier
Concen-
4 Hours
Granule
Test
ZBA 1
HPO 2
tration
Dissolution
Size
#
Sample
Modifier
(%)
(%)
(%)
(%)
Micro
3
Control
—
40
60
0
9.84
(5 μL)
3
3A
Glycerin
40
55
5
**
3
3B
Lecithin
40
55
5
1.52
3
3C
Tween20
40
55
5
**
3
3D
Tween80
40
55
5
34.84
4
Control
—
40
60
0
10.27
4
4A
Glycerin
40
57.5
2.5
**
4
4B
1% Glycerin +
40
58
2
2.87
1% Lecithin
Mini
5
Control
—
50
50
0
5.85
(25 μL)
5
5A
Propylene Glycol
50
47.5
2.5
12.31
5
5B
Propylene Glycol
40
54.7
5.3
23.44
5
5C
Sodium Stearate
50
47.5
2.5
4.56
6
6A
Propylene Glycol
40
50
10
18.75
6
6B
Propylene Glycol*
40
50
10
32.08
6
6C
Polyethylene
40
50
10
34.11
Glycol
6
6D
Polyethylene
40
50
10
36.79
Glycol*
7
Control
—
40
60
0
3.92
7
7A
Propylene Glycol
40
59
1
5.43
7
7B
Propylene Glycol
40
58
2
15.10
7
7C
Propylene Glycol
40
57
3
19.28
7
7D
Propylene Glycol
40
56
4
23.87
7
7E
Propylene Glycol
40
55
5
22.08
8
Control
—
40
60
0
4.82
8
8A
Propylene Glycol
40
50
10
37.97
8
8B
Propylene Glycol
40
45
15
47.50
9
Control
Propylene Glycol
40
57.5
2.5
16.54
9
9A
Propylene Glycol +
40
57
3
19.37
0.5% NaHCO 3
Mega
1
Control
—
40
60
0
2.78
(50 μL)
1
Sugar
49.20% sucrose in
40
56
4
1.44
water
2
2A
Glycerin
40
57.5
2.5
2.66
2
2B
Glycerin
40
57.5
2.5
2.51
2
2C
Glycerin
40
57.5
2.5
2.77
2
Control
—
40
60
0
2.44
*Mixed with ZBA first then with hydrogenated palm oil
** Mixture was too viscous to make granules.
1 ZBA = The salt of zinc and butyric acid in a ratio of 1:2.
2 HPO = Hydrogenated palm oil.
[0017] Dissolution testing. Dissolution was conducted with a mechanical shaking water bath that was loaded with individual flask for each sample. 0.5 grams of granules was weighed into a 125 mL Erlenmeyer flask containing 70 mL deionized water at 37° C. The flask was agitated in a 37±2° C. shaking bath for 4 hours. A 0.5 mL aliquot of solution was collected at 0.5, 1, 2, and 4 hours interval for gas chromatography analysis to determine the amount of butyric acid released at each time point. Dissolution percentage at each time point was determined by dividing the amount of butyric acid in solution at that specific time point with the amount of total butyric acid in the granule.
[0018] Particle size analysis. 20-30 g of pearls was analyzed on a Malvern Mastersizer 2000. Particle size distribution was determined with laser diffraction technique by measuring the intensity of light scattering as a laser beam passes through a dispersed particulate sample.
[0019] Gas chromatography (GC) analysis. 0.5 mL aliquot of dissolution solution was loaded into a GC vial containing 1 mL of 500 ppm valeric acid in 1N HCl. The total of 1.5 mL solution in the GC vial was mixed and analyzed on a gas chromatograph.
[0020] Effect of propylene glycol (PG) on dissolution. Four different encapsulated prototypes were produced to make a product of encapsulated ZBA (EZBA) with HPO. For the control mixture, only ZBA and HPO were in the mixture. To test the effect of propylene glycol on dissolution, 2.5%, 5.0% and 10.0% of propylene glycol was included for making the encapsulates S1, S2, and S3 respectively. Gram quantities of encapsulated prototypes were then made for the initial production utilizing spray-freeze tower/technology. The dissolution results for these encapsulated prototypes are listed in Table 3. As the concentration of propylene glycol (PG) is increased, the dissolution rate increased, allowing for PG dose dependent control of dissolution rate. Sample S1 with 2.5% of propylene glycol had dissolution of 38.63%, and sample S3 with 10% propylene glycol had dissolution rate of 83%, representing the percent of total butyric acid released within 4 hours ( FIG. 1 ).
[0000]
TABLE 3
Dissolution of granules with different
concentration of propylene glycol.
Hydrogenated
Propylene
Dissolution Time
ZBA
Vegetable Oil
glycol
0.5 h
1 h
2 h
4 h
Sample
(%)
(%)
(%)
(%)
(%)
(%)
(%)
Control
40
60.0
0
6.67
7.46
8.53
10.43
S1
40
57.5
2.5
17.10
22.86
29.51
38.63
S2
40
55.0
5.0
23.60
33.53
44.94
55.79
S3
40
50.0
10.0
41.47
57.33
75.67
83.12
[0021] To determine the effect of propylene glycol on the structure of the encapsulation granules, tests were conducted to examine the penetration of a red dye into the interior of the encapsulated granules. Formulations of both control and fast release granules were soaked in a red dye solution for 16 hours. The granules were then broken open to expose the cores. FIG. 2 shows that the propylene glycol in the formulation produces micro-channels that allow the dye to penetrate and for the encapsulated active to dissolve. The control granule did not take up any of the dye and therefore does not have the micro-porous structure.
EXAMPLE 2
Performance Trial in Broiler Chickens
[0022] A chicken, broiler performance trial was completed to understand if granules with different in-vitro dissolution rates would perform differently in an animal model. In a typical, broiler the passage rate is 2-6 hours through the gut and a fast release mechanism is needed such that the majority of the active ingredient is released in the hind gut. Therefore two different granules were made, one with a fast dissolution, and one with a slow dissolution. The controls did not contain any active ingredients, while the other treatment groups included the ZBA powder treatment, ZBA slow release granules treatment, and ZBA fast release granule treatment. The experiment used 72 cages of 10 male Cobb×Cobb 500 broiler chickens. The treatments were replicated in eighteen blocks where the four treatments were randomized within each block.
[0023] Encapsulated ZBA formulations used in the animal trial:
Slow Release Formula
[0000]
40% ZBA
60% HPO
Fast Release Formula
[0000]
40% ZBA
57.5% HPO
2.5% Propylene Glycol
[0000]
TABLE 4
Treatments used in the performance trial.
Amount of
Amount
supplement
Amount of
of butyric
Treatment
added in
supplemental
acid
Treatments
Details
Treatment
zinc added
added
1. Negative
Basal Diet +
0.69 kg/MT
153 ppm
—
Control
ZnSO 4
2. ZBA Powder
Basal Diet +
0.56 kg/MT
153 ppm
407 ppm
Zinc and
Butyric Acid
Salt Powder
3. Slow
Basal Diet +
1.4 kg/MT
153 ppm
407 ppm
Release ZBA
Slow Release
Granule
Granule
4. Fast Release
Basal Diet +
1.4 kg/MT
153 ppm
407 ppm
ZBA Granule
Fast Release
Granule
[0029] All the treatments contained equal amount of zinc and treatments B, C and D had same amount of butyric acid. The diet given in Tables 5 and 6 was supplemented with the treatments in Table 4. The starter diet was fed day 0 to 14 and the grower diet was fed day 14 to 28. All diets were fed as non-pelleted mash feed.
[0000]
TABLE 5
Diet formulation for starter and grower phases.
Starter
Grower
(0 to 14 d)
(14-28 d)
Ingredient Name
% inclusion
% inclusion
Corn, yellow, grain
63.73
67.59
Soybean meal dehulled, solvent
26.28
22.6
De-oiled DDGS (poet)
4
4
Fat, vegetable
1.8
1.8
Dicalcium phosphate.
1.49
1.33
Calcium carbonate
1.02
1
Salt, plain (NaCl)
0.42
0.42
Methionine MHA
0.41
0.38
L-Lysine
0.52
0.53
L-Threonine 98.5
0.17
0.18
Trace Mineral
0.08
0.08
Vitamin premix
0.07
0.07
TiO2 marker
0.4
0.4
Ronozyme p-(ct)
0.02
0.02
[0000]
TABLE 6
Diet formulation for starter and grower phases.
Starter
Grower
(0 to 14 d)
(14-28 d)
Nutrient Name
% inclusion
% inclusion
Dry matter
87.96
87.90
Protein, crude
19.72
18.26
Fat, crude
4.46
4.56
Fiber, crude
2.29
2.25
Calcium
0.90
0.85
Phos. Total
0.64
0.6
Phos., available
0.45
0.42
M.e. Poultry
3,000
3,040
Methionine
0.68
0.63
Lysine
1.4
1.32
Tryptophan
0.26
0.22
Threonine
0.94
0.88
Sodium
0.2
0.2
Potassium
0.73
0.67
Chloride
0.29
0.29
dig methionine
0.64
0.6
dig cysteine
0.27
0.25
dig lysine
1.28
1.2
dig tryptophan
0.23
0.21
dig threonine
0.82
0.77
dig isoleucine
0.83
0.75
dig histidine
0.48
0.44
dig valine
0.93
0.85
dig leucine
1.63
1.54
dig arginine
1.16
1.05
dig phenylalanine
0.95
0.87
dig TSAA
0.91
0.85
[0030] Bird weights and feed consumption by cage were recorded on Days 0, 14, 21, 28. On days 14 and 28, after weighing, 4 birds per cage were harvested. From each of the harvested birds, a 1 inch section from the beginning of the ileum was cut off and flash frozen. The remaining intestinal tract was cut into 3 sections (upper, middle and cecal), the intestinal contents for each section were pooled by cage, and frozen in liquid nitrogen. A sample of excreta was collected by cage and frozen.
[0031] The samples of the feed and intestinal contents were analyzed for butyric acid by gas chromatography.
Results
[0032] The performance results from the trial are shown in Table 7. Feeding the fast release granule to the birds resulted in better growth performance, as shown by the improvement in feed conversion ( FIG. 3 ) and the improvement in weight gain after 28 days.
[0000]
TABLE 7
Performance results after 28 days.
Treatment
Feed Intake
Feed Conversion
Avg. Wt. (kg)
1. Zinc Sulfate Powder
10.93
1.620
1.010
2. ZBA Powder
11.06
1.589
1.043
3. Slow Release
11.04
1.601
0.995
Control Granule
4. Fast Release
11.33
1.570
1.046
Granule
[0033] From the intestinal contents collected at day 28, for the birds fed the control diet, or the ZBA in powder form, there was no detectible butyric acid in the ileal contents ( FIG. 4 ). Indicating, the butyric acid is absorbed in the bird before it reaches the small intestine, and is not available in the small intestine, where it can enhance intestinal barrier function. The ileal contents of the birds fed the slow release granules or fast release granules have detectable levels of butyric acid. The birds fed the slow release granule diet had a higher amount of butyric acid in their intestinal contents as compared to the birds fed the fast release granules ( FIG. 4 ). This is consistent with butyric acid still being inside the slow release granule and is therefore not providing the optimal benefits to the birds.
[0034] The butyric acid levels in the day 28 excreta of the birds fed the diets containing the fast release granules are similar to that in the control treatment with no added butyric acid and the ZBA treatment, in which no butyric acid was detected in the jejunum. This illustrates that most of the butyric acid supplemented as fast release granules was released in the gut of the birds. The overall higher levels of butyric acid detected in the excreta are likely due to the fermentation by bacteria in the ceca and excreta of the birds. This means that the majority of the butyric acid being detected in the excreta is not the butyric acid that was added to the diet ( FIG. 5 ).
Discussion
[0035] It is clear from the 28 day performance data that the best growth performance is obtained from the treatment that contains the fast release formulation of ZBA (Table 7). The fast release formulation allows for sustained release throughout the gastrointestinal tract of the animal ( FIG. 4 ) and the excreta of the bird fed the fast release formulation does not contain more butyric acid than the excreta from the birds fed the control diet that does not have ZBA supplementation.
EXAMPLE 3
Release of Histidine
[0036] Histidine encapsulation granules were prepared with a pilot encapsulation system as described generally in Example 1 to contain no propylene glycol and 50% histidine or 2% propylene glycol and 50% histidine. A United States pharmacopeia (USP) dissolution test was conducted to determine the release of histidine from the encapsulation granules. Briefly, 5 grams of granules was weighed into a Distek dissolution bowl containing 700 mL deionized water at 37° C. The mixture was stirred with a flat agitator blade at 100 rpm for 8 hours, with samples collected after 2, 4, 6, and 24 hours. The results indicated that propylene glycol significantly increased the release of histidine from its encapsulation granules from 20% to over 80% after 24 hours of dissolution, thus supporting the use of propylene glycol to modify the release of histidine from encapsulation.
EXAMPLE 4
Release of CBA
[0037] CBA (the salt of copper and butyric acid in a 1:2 molar ratio) encapsulation granules were prepared with a pilot encapsulation system as described generally in Example 1 and formulated to contain 50% CBA and 0 to 4% of propylene glycol with a pilot encapsulation system. The granules generated were tested for release of a salt of copper and butyric acid in a United States pharmacopeia (USP) dissolution assay. Briefly, 5 grams of granules was weighed into a Distek dissolution bowl containing 700 mL deionized water at 37° C. The mixture was stirred with a flat agitator blade at 100 rpm with samples collected after 1, 2, 4, and 8 hours. The results indicated that propylene glycol increased the release of the salt of copper and butyric acid in a dose dependent manner. The release was increased from 11% in the control granules to 35% in the granules with 4% propylene glycol after 8 hours of dissolution. It can be concluded that propylene glycol can be used to modify the release of ZBA from encapsulate.
EXAMPLE 5
Release of CBA
[0038] CBA encapsulation granules as described generally in Example 1 were formulated to contain from 0 to 2% of propylene glycol and CBA, which has a distinct blue color. The granules were placed in a dissolution apparatus for about 8 hours. By visual examination, propylene glycol formulated material had a shallower blue color and therefore increased the release of CBA in a dose dependent manner from encapsulate.
EXAMPLE 6
Release of ZBA
[0039] ZBA encapsulation granules as described generally in Example 1 were prepared in the laboratory. The granules were cut open and examined with scanning electronic microscopy (SEM). The analysis established that the granules contained propylene glycol were more porous than that without propylene glycol. Propylene glycol present in the granulation process helps form a unique three dimensional structure within the granules to facilitate the release of actives from encapsulates as evidenced by the microscopic observation of the gradual release of ZBA from the granules.
[0040] The foregoing description and drawings comprise illustrative embodiments of the present inventions. The foregoing embodiments and the methods described herein may vary based on the ability, experience, and preference of those skilled in the art. Merely listing the steps of the method in a certain order does not constitute any limitation on the order of the steps of the method. The foregoing description and drawings merely explain and illustrate the invention, and the invention is not limited thereto, except insofar as the claims are so limited. Those skilled in the art that have the disclosure before them will be able to make modifications and variations therein without departing from the scope of the invention. | A method of forming a granule having an internal three-dimensional framework of channels to control and sustain the release of an active ingredient for enteric delivery of the active ingredient in an animal fed the granule. In the composition of the granules hydrogenated vegetable oil, HVO for example, is combined with a modifier to create a granule with channels through which the active ingredient is released. The active ingredients, including but not limited to metal salts of butyric acid, can be released in the lower gut of the animal where it will best benefit the animal. By adjusting the amount of the modifier, the release rate of the active can be adjusted to suit the passage rate of the species of animal being fed. | 0 |
RELATED APPLICATIONS
This application is a continuation of U.S. application Ser. No. 10/661,721 entitled “System and Methods for Sharing Configuration Information with Multiple Processes Via Shared Memory” filed Sep. 12, 2003 now U.S. Pat. No. 7,139,894, which is incorporated herein by reference.
TECHNICAL FIELD
The present invention relates, generally, to shared memory systems and methods, and, more particularly, to shared memory systems and methods for storing configuration information for server-side services.
BACKGROUND OF THE INVENTION
In computing systems, computer processes and services commonly require configuration values and connection strings for operation. Computer services are often dispersed in various configuration files, registry values, web pages, or data source name (DSN) entries. Computer processes and services commonly require configuration files to store process and service settings. When processes and services are installed onto a computer, a configuration file is created to define values of certain parameters necessary for the process and service to function correctly. During execution, the process or service accesses the configuration file to retrieve the appropriate parameters. Such configuration files commonly include initialization files, management information format files, and the registry. The registry, for example, is a central database that stores information in a hierarchy in order to allow the system to accommodate one or more users, processes, or hardware devices. Processes and services constantly access the registry to reference, for example, user profiles, a list of processes installed on the system and the document types each process can utilize, property sheet settings, a list of hardware connected to the system, and a list of accessible ports.
While storing configuration values and connection strings in registry values, data files, web pages, and data source name entries satisfies the needs for such information, computer systems typically depend on configuration files that are designed specifically for processes or services and that may reside on remote systems. The specifically designed configuration files do not allow for real-time updates thereof without service interruption, do not allow immediate access to configuration values, and do not enable uniformity between different services. Computing systems, particularly server systems, require immediate access to configuration values and connection strings in order to provide acceptable response times to client side requests.
Computer systems that share memory between multiple processes or services require a mechanism to protect the integrity of the shared resources. Computer systems often lock files being accessed or updated to ensure mutually exclusive access to the files. The locking of files prevents two services from modifying a file at the same time which might lead to corrupted data in the files. A downside of locking files is that when another service needs to access the file, the service may have to wait until the file has been unlocked by the first service. Additionally, multiple users on the same computer system present security problems with shared memory and the data stored therein. The shared memory must not allow unauthorized users to access sensitive data.
Accordingly, there is a need in the art for a unified system and method for storing server-side configuration data for multiple computer services.
There is also a need in the art for a unified system and method for updating server-side configuration data for multiple computer services while ensuring that data updates do not interrupt services accessing the configuration data.
Additionally, there is a need in the art for a system and method to manage non-locked shared memory to store settings for multiple processes.
Further, there is a need in the art for a system and method for controlling access to portions of shared memory data to particular computer accounts.
SUMMARY OF THE INVENTION
Broadly described, the present invention comprises a system for facilitating configuration information sharing with a plurality of processes or services via non-locked shared memory. More particularly, the present invention comprises a system for creating, accessing, updating, securing, and managing non-locked shared memory and methods which: (1) allocate a region of computer memory for storing configuration information potentially accessible to a plurality of processes or services; (2) receive and store initial configuration information in the allocated memory; (3) insert or update configuration information without impeding access to the configuration information by the plurality of processes or services; (4) provide configuration information to the plurality of processes or services; and (5) secure the allocated memory so that only certain processes or services have access to certain configuration information.
Advantageously, the present system provides secure shared memory because the system architecture allows access to shared memory only by processes or services actually running on the computer system where the shared memory resides. Generally, configuration information persists on a database protected from outside systems via a secured communication link and firewall. Only the operator may update or add information to the database which is then propagated to the shared memory on the target computer systems. Additionally, the system provides read-only application processing interfaces, thus protecting the integrity of configuration information in shared memory. The present invention further protects configuration information by creating memory sections that are accessible only by certain processes or applications identified in an access control list.
The present invention also provides real-time updating of shared memory without interrupting or impeding access to the shared memory by processes and services. During the real-time updating, processes and services use original configuration information until the updated configuration information is identified as being usable. Thereafter, processes and services access the updated configuration information from shared memory. Using a “bottom-up” approach, shared memory may be modified in real-time while providing a seamless transition between the original configuration information and the updated configuration information.
The configuration information accessible in shared memory generally includes runtime information utilized by processes or services during operation, including but not limited to, data communication connection information between the computer system in which the shared memory is present (i.e., the local computer system) and other computing resources (i.e., port and wire information), and numeric or character string information specific to a particular service or process (i.e., genre and record information). Therefore, the present invention eliminates the scattering of configuration information for services and processes throughout various registry values, data files, web pages, or DSN entries.
Other features and advantages of the present invention will become apparent upon reading and understanding the present specification when taken in conjunction with the appended drawings.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 displays a block diagram representation of a network environment on which the invention is implemented in accordance with an exemplary embodiment of the present invention.
FIG. 2 displays a block diagram representation of a system environment on which the invention is implemented in accordance with an exemplary embodiment of the present invention.
FIG. 3 displays a block diagram representation illustrating ports and wires modeling of the communication links between multiple resources in accordance with an exemplary embodiment of the present invention.
FIG. 4 displays an example genre structure in accordance with an exemplary embodiment of the present invention.
FIG. 5 displays a block diagram representation illustrating a system for accessing configuration data in shared memory in accordance with an exemplary embodiment of the present invention.
FIG. 6 displays a block diagram representation illustrating memory tables present in shared memory in accordance with an exemplary embodiment of the present invention.
FIG. 7 displays a flowchart representation of a method of initializing shared memory in accordance with an exemplary embodiment of the present invention.
FIG. 8 displays a pseudo-code representation for writing or updating configuration data in shared memory in accordance with an exemplary embodiment of the present invention.
FIGS. 9A-9B display a flowchart representation of a method of updating or adding configuration data in shared memory in accordance with an exemplary embodiment of the present invention.
FIGS. 10A-10C display a flowchart representation of a method of accessing data from shared memory in accordance with an exemplary embodiment of the present invention.
FIG. 11 displays a flowchart representation of a method of accessing port-handle information in accordance with an exemplary embodiment of the present invention.
FIG. 12 displays a flowchart representation of a method of accessing genre-handle information in accordance with an exemplary embodiment of the present invention.
FIG. 13 displays a flowchart representation of a method of accessing port information in accordance with an exemplary embodiment of the present invention.
FIG. 14 displays a flowchart representation of a method of accessing wire information in accordance with an exemplary embodiment of the present invention.
FIG. 15 displays a flowchart representation of a method of accessing genre information in accordance with an exemplary embodiment of the present invention.
FIG. 16 displays a flowchart representation of a method of accessing record information in accordance with an exemplary embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the drawings, in which like numerals represent like components or steps throughout the several views, FIG. 1 displays a block diagram representation of a network environment 100 on which the invention is implemented in accordance with an exemplary embodiment of the present invention. The network environment 100 comprises an operator system 134 residing at a first location. The operator system 134 is configured with hardware and software (see FIG. 2 ) appropriate to perform tasks and provide capabilities and functionality as described herein. The operator system 134 comprises a configuration data communication generator 128 , a configuration data user interface 131 , and an operation controller 146 .
The configuration data user interface 131 provides an operator or administrator with a user interface to add or modify data, such as configuration data, which is stored in a database 137 , described below. In the exemplary embodiment of the present invention, the configuration data user interface 131 comprises program modules or machine instructions that perform the above-described tasks when executed on the operator system's 134 central processing unit (CPU).
The configuration data user interface 131 connects communicatively to the configuration data communication generator 128 . The configuration data communication generator 128 is adapted to receive data, such as configuration data, from the configuration data user interface 131 . In the exemplary embodiment of the present invention, the configuration data communication generator 128 comprises program modules or machine instructions that perform certain tasks when executed by the CPU. Additionally, the configuration data communication generator 128 creates executable machine instructions or code which incorporates the configuration data received from the configuration data user interface 131 . The generated code is then sent to target systems 104 a , 104 z , described below, for configuration data updates. The configuration data communication generator 128 connects communicatively to target systems 104 a , 104 z . Preferably, the configuration data communication generator 128 connects to the target systems 104 a , 104 z via a secure communication link and through a firewall 125 a , 125 b , described below. Such connection is generally established via a typical network protocol. For example, and not limitation, the configuration data communication generator 128 connects to the target systems 104 a , 104 z using the simple object access protocol (SOAP) to exchange structured and type information via the network environment 100 . In the exemplary embodiment of the present invention, the executable machine instructions or code generated by the configuration data communication generator 128 , described above, is implemented in extensible markup language (XML).
The operation controller 146 connects communicatively to the database 137 and the configuration data communication generator 128 . The operation controller 146 is adapted to receive data from the database 137 and provide data to the configuration data communication generator 128 . In the exemplary embodiment of the present invention, the operation controller 146 comprises program modules or machine instructions that perform certain tasks when executed by the CPU. For example, and not limitation, the operation controller 146 determines whether a target system's 104 a , 104 z shared memory 113 a , 113 z , described below, is empty (i.e., because the target system just entered the network after reboot or because the target system is a newly added system). If such a determination is made, the operation controller 146 retrieves data from the database 137 to provide to the configuration data communication generator 128 , which in turn provides the data to the appropriate target system 104 a , 104 z . The method of determining whether a target system 104 a , 104 z is empty and then providing appropriate data accordingly is described below with reference to FIG. 7 .
The operator system 134 connects communicatively to a database 137 which stores data. The database 137 is a memory device capable of storing and retrieving data including, but not limited to, random access memory (RAM), flash memory, magnetic memory devices, optical memory devices, hard disk drives, removable volatile or non-volatile memory devices, optical storage mediums, magnetic storage mediums, or RAM memory cards. Alternatively, the database 137 may be a remote storage facility accessible through a wired and/or wireless network system. Additionally, the database 137 may be a memory system comprising a multi-stage system of primary and secondary memory devices, as described above. The primary memory device and secondary memory device may operate as a cache for the other or the second memory device may serve as a backup to the primary memory device. In yet another example, the database 137 may be a memory device configured as a simple database file. The database 137 is preferably implemented as a searchable, relational database using a structured-query-language (SQL). Typically, the database 137 stores the persisted configuration data and connection strings for the services 119 a , 119 b , 140 a , 140 z located on the target system 104 a , 104 z.
In the exemplary embodiment of the present invention, the network environment 100 comprises a plurality of target systems 104 a , 104 z residing at multiple locations. The target systems 104 a , 104 z are configured with hardware and software (see FIG. 2 ) appropriate to perform tasks and provide capabilities and functionality as described herein. Each target system 104 a , 104 z comprises a web server, such as Internet Information Server (IIS) 107 a , 107 z ; shared memory 113 a , 113 z ; a shared memory manager 116 a , 116 z ; a configuration data interface agent 110 a , 110 z ; and a plurality of services 119 a , 119 z , 140 a , 140 z . The ellipsis between target system “A” 104 a and target system “Z” 104 z illustrates that a plurality of target systems may exist in the network environment 100 and, therefore, the network environment 100 is not limited to two target systems as shown in FIG. 1 .
The IIS 107 a , 107 z connects communicatively to a remote network such as, but not limited to, the Internet 101 or a local area network (LAN). One skilled in the art will recognize that the IIS 107 a , 107 z is a web server designed to deliver web documents to remote clients that request such web documents. IIS 107 a , 107 z is a web server designed to run on “WINDOWS NT®” platforms available from Microsoft Corporation of Redmond, Wash. Additionally, the IIS 107 a , 107 z connects communicatively to the shared memory 113 a , 113 z.
The shared memory manager 116 a , 116 z connects communicatively to the shared memory 113 a , 113 z which contains data, such as configuration data. The shared memory manager 116 a , 116 z comprises program modules or machine instructions that perform certain tasks when executed by the CPU. In the exemplary embodiment of the present invention, the shared memory manager 116 a , 116 z handles all requests for data residing in shared memory 113 a , 113 z . Additionally, the shared memory manager 116 a , 116 z updates and adds data to the shared memory 113 a , 113 z . In the exemplary embodiment of the present invention, the shared memory manager 116 a , 1116 z only updates and adds data to the shared memory 113 a , 113 z if requested by the configuration data interface agent 110 a , 110 z , described below, otherwise the shared memory manager 116 a , 116 z only provides read access to the shared memory 113 a , 113 z.
The shared memory 113 a , 113 z stores data and provides data to the shared memory manager 116 a , 116 z . In the exemplary embodiment of the present invention, the shared memory 113 a , 113 z is a volatile memory device (often called main memory) capable of storing and retrieving data including, but not limited to, random access memory (RAM), or any other memory device that provides rapid storing and retrieving of data. The data residing in shared memory 113 a , 113 z includes, but is not limited to, configuration data, ports, wires, genres, records, or permission schemas. Additionally, the shared memory 113 a , 113 z maintains configuration data, ports, and wires relevant to the local target system 104 a , 104 z . Therefore, the content of shared memory 113 a , 113 z across the network environment 100 differs for each target system 104 a , 104 z.
The plurality of services 119 a , 119 z , 140 a , 140 z include, but are not limited to, program modules, applications, machine instructions, software code, or any combination thereof. Generally, services 119 a , 119 z , 140 a , 140 z perform tasks and provide desirable capabilities in order to reach a specific result. Services 119 a , 119 z , 140 a , 140 z typically require system resources and configuration data to perform properly. In addition, services 119 a , 119 z , 140 a , 140 z may require access to back-end functionality provided on various server systems (also called resources) 122 a , 122 z , 143 a , 143 z . The services 119 a , 119 z , 140 a , 140 z connect communicatively to the shared memory 113 a , 113 z . For example, and not limitation, if a service needs configuration data or a connection to a server system, the service 119 a , 119 z , 140 a , 140 z sends a request to the shared memory 113 a , 113 z for such data. The target system 104 a , 104 z may contain a plurality of services 119 a , 119 z , 140 a , 140 z and, therefore, should not be limited to the number of services shown in FIG. 1 .
Server systems 122 a , 122 z , 143 a , 143 z may be configured with hardware and software (see FIG. 2 ) appropriate to perform tasks and provide capabilities and functionality as described herein. Server systems 122 a , 122 z , 143 a , 143 z typically provide back-end support to the services 119 a , 119 z , 140 a , 140 z running on the target systems 104 a , 104 z . Each server system 122 a , 122 z , 143 a , 143 z may contain differing support program modules, applications, software, or hardware. For example, one server system may contain billing software, while another server system contains authentication software. In the exemplary embodiment of the present invention, services 119 a , 119 z , 140 a , 140 z connect to server systems 122 a , 122 z , 143 a , 143 z for support and functionality.
The configuration data interface agent 110 a , 110 z connects communicatively to the shared memory manager 116 a , 116 z . The configuration data interface agent 110 a , 110 z provides data, such as configuration data, to the shared memory manager 116 a , 116 z , which then updates shared memory 113 a , 113 z . Additionally, the configuration data interface agent 110 a , 110 z connects communicatively to the operator system 134 via a secured communication link. A secure communication link can be established by encrypting any communication through the secure communication link using secure sockets layer (SSL). In the exemplary embodiment of the present invention, the operator system 134 provides a communication, comprising configuration data from the database 137 , to the configuration data interface agent 110 a , 110 z which then interprets the communication and provides the configuration data to the shared memory manager 116 a , 116 z for storing into shared memory 113 a , 113 z . Generally, only the configuration data interface agent 110 a , 110 z has access to the write-enabled APIs used to write data to shared memory 113 a , 113 z.
The target system 104 a , 104 z and the operator system 134 are separated by a firewall 125 a , 125 b . Typically, a firewall 125 a , 125 b is a system designed to prevent unauthorized access to a computer system or network and may be implemented by hardware, software, or a combination thereof. A firewall 125 a , 125 b assists in making a connection between two systems secure.
One skilled in the art will recognize that connecting communicatively may include any appropriate type of connection including, but not limited to, analog, digital, wireless and wired communication channels. Such communication channels include, but are not limited to, copper wire, optical fiber, radio frequency, infrared, satellite, or other media.
In an alternative embodiment of the present invention, the target systems 104 a , 104 z may not be in communication with an operator system 134 . In such a configuration, the configuration data interface agent 110 a , 110 z does not receive configuration data from the database 137 via the configuration data communication generator 128 . Instead, configuration data is retrieved from the local registry of the target system 104 a , 104 z . To change data in the shared memory 113 a , 113 z , the values in the registry of the target system 104 a , 104 z may be modified by an operator.
FIG. 2 illustrates an example of a suitable computing system environment 200 on which the invention is implemented. The computing system environment 200 is only one example of a suitable computing environment and is not intended to suggest any limitation as to the scope of use or functionality of the invention. Neither should the computing environment 200 be interpreted as having any dependency or requirement relating to any one or combination of components illustrated in the exemplary operating environment 200 .
The invention is operational with numerous other general purpose or special purpose computing system environments or configurations. Examples of well known computing systems, environments, and/or configurations that may be suitable for use with the invention include, but are not limited to, personal computers, server computers, hand-held or laptop devices, multiprocessor systems, microprocessor-based systems, set top boxes, programmable consumer electronics, network PCs, minicomputers, mainframe computers, distributed computing environments that include any of the above systems or devices, and the like.
The invention may be described in the general context of computer-executable instructions, such as program modules, being executed by a computer. Generally, program modules include routines, programs, objects, components, or data structures that perform particular tasks or implement particular abstract data types. The invention may also be practiced in distributed computing environments where tasks are performed by remote processing devices that are linked through a communications network. In a distributed computing environment, program modules may be located in both local and remote computer storage media including memory storage devices.
With reference to FIG. 2 , an exemplary system for implementing the invention includes a general purpose computing device in the form of a computer 210 . Components of computer 210 may include, but are not limited to, a processing unit 220 , a system memory 230 , and a system bus 221 that couples various system components including the system memory 230 to the processing unit 220 . The system bus 221 may be any of several types of bus structures including a memory bus or memory controller, a peripheral bus, and a local bus using any of a variety of bus architectures. By way of example, and not limitation, such architectures include Industry Standard Architecture (ISA) bus, Micro Channel Architecture (MCA) bus, Enhanced ISA (EISA) bus, Video Electronics Standards Association (VESA) local bus, and Peripheral Component Interconnect (PCI) bus also known as Mezzanine bus.
Computer 210 typically includes a variety of computer readable media. Computer readable media can be any available media that can be accessed by computer 210 and includes both volatile and nonvolatile, removable and non-removable media. By way of example, and not limitation, computer readable media may comprise computer storage media and communication media. Computer storage media includes both volatile and nonvolatile, removable and non-removable media implemented in any method or technology for storage of information such as computer readable instructions, data structures, program modules or other data. Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, digital versatile disks (DVD) or other optical disk storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other medium which can be used to store the desired information and which can be accessed by computer 210 . Communication media typically embodies computer readable instructions, data structures, program modules or other data in a modulated data signal such as a carrier wave or other transport mechanism and includes any information delivery media. The term “modulated data signal” means a signal that has one or more of its characteristics set or changed in such a manner as to encode information in the signal. By way of example, and not limitation, communication media includes wired media such as a wired network or direct-wired connection, and wireless media such as acoustic, RF, infrared and other wireless media. Combinations of any of the above should also be included within the scope of computer readable media.
The system memory 230 includes computer storage media in the form of volatile and/or nonvolatile memory such as read only memory (ROM) 231 and random access memory (RAM) 232 . A basic input/output system 233 (BIOS), containing the basic routines that help to transfer information between elements within computer 210 , such as during start-up, is typically stored in ROM 231 . RAM 232 typically contains data and/or program modules that are immediately accessible to and/or presently being operated on by processing unit 220 . By way of example, and not limitation, FIG. 2 illustrates operating system 234 , application programs 235 , other program modules 236 , and program data 237 .
The computer 210 may also include other removable/non-removable, volatile/nonvolatile computer storage media. By way of example only, FIG. 2 illustrates a hard disk drive 241 that reads from or writes to non-removable, nonvolatile magnetic media, a magnetic disk drive 251 that reads from or writes to a removable, nonvolatile magnetic disk 252 , and an optical disk drive 255 that reads from or writes to a removable, nonvolatile optical disk 256 such as a CD ROM or other optical media. Other removable/non-removable, volatile/nonvolatile computer storage media that can be used in the exemplary operating environment include, but are not limited to, magnetic tape cassettes, flash memory cards, digital versatile disks, digital video tape, solid state RAM, solid state ROM, and the like. The hard disk drive 241 is typically connected to the system bus 221 through a non-removable memory interface such as interface 240 , and magnetic disk drive 251 and optical disk drive 255 are typically connected to the system bus 221 by a removable memory interface, such as interface 250 .
The drives and their associated computer storage media discussed above and illustrated in FIG. 2 , provide storage of computer readable instructions, data structures, program modules and other data for the computer 210 . In FIG. 2 , for example, hard disk drive 241 is illustrated as storing operating system 244 , application programs 245 , other program modules 246 , and program data 247 . Note that these components can either be the same as or different from operating system 234 , application programs 235 , other program modules 236 , and program data 237 . Operating system 244 , application programs 245 , other program modules 246 , and program data 247 are given different numbers here to illustrate that, at a minimum, they are different copies. A user may enter commands and information into the computer 210 through input devices such as a keyboard 262 and pointing device 261 , commonly referred to as a mouse, trackball or touch pad. Other input devices (not shown) may include a microphone, joystick, game pad, satellite dish, scanner, or the like. These and other input devices are often connected to the processing unit 220 through a user input interface 260 that is coupled to the system bus 221 , but may be connected by other interface and bus structures, such as a parallel port, game port or a universal serial bus (USB). A monitor 291 or other type of display device is also connected to the system bus 221 via an interface, such as a video interface 290 . In addition to the monitor, computers may also include other peripheral output devices such as speakers 297 and printer 296 , which may be connected through an output peripheral interface 295 .
The computer 210 may operate in a networked environment using logical connections to one or more remote computers, such as a remote computer 280 . The remote computer 280 may be a personal computer, a server, a router, a network PC, a peer device or other common network node, and typically includes many or all of the elements described above relative to the computer 210 , although only a memory storage device 281 has been illustrated in FIG. 2 . The logical connections depicted in FIG. 2 include a local area network (LAN) 271 and a wide area network (WAN) 273 , but may also include other networks. Such networking environments are commonplace in offices, enterprise-wide computer networks, intranets and the Internet.
When used in a LAN networking environment, the computer 210 is connected to the LAN 271 through a network interface or adapter 270 . When used in a WAN networking environment, the computer 210 typically includes a modem 272 or other means for establishing communications over the WAN 273 , such as the Internet. The modem 272 , which may be internal or external, may be connected to the system bus 221 via the user input interface 260 , or other appropriate mechanism. In a networked environment, program modules depicted relative to the computer 210 , or portions thereof, may be stored in the remote memory storage device. By way of example, and not limitation, FIG. 2 illustrates remote application programs 285 as residing on memory device 281 . It will be appreciated that the network connections shown are exemplary and other means of establishing a communications link between the computers may be used.
FIG. 3 displays a block diagram representation illustrating ports and wires modeling of the communication links between multiple resources in accordance with an exemplary embodiment of the present invention. As discussed above with regard to FIG. 1 , a target system 104 a , 104 z comprises an IIS 107 a , 107 b that assists in facilitating communications to remote networks. Such remote networks may include connections to server systems 122 a , 122 z , 143 a , 143 z as described above. FIG. 3 illustrates, by way of example, the connection (“ports” and “wires”) between the target systems 104 a , 104 z and the server systems (also called resources) 122 a , 122 z , 143 a , 143 z.
In the exemplary embodiment of the present invention, the target system 104 a , 104 z , illustrated by IIS 107 a , 107 b , 107 z in FIG. 3 , comprise at least one port 304 a - 304 e . The ports 304 a - 304 e comprise at least one wire 316 a - 316 f that facilitates a connection to an outside resource, such as a server system 122 a , 122 z , 143 a , 143 z . A single port 304 a - 304 e can comprise multiple wires 316 a - 316 f . As illustrated in FIG. 3 , the server systems 122 a , 122 z , 143 a , 143 z may be systems comprising SQL systems 310 a , 310 z . The SQL systems 310 a , 310 z comprise databases 313 a , 313 z providing access to various data. Like the target systems 104 a , 104 z , the server systems 122 a , 122 z , 143 a , 143 z , illustrated by SQL systems 310 a , 310 z in FIG. 3 , comprise at least one port 304 f , 304 g . The IIS ports 304 a - 304 e connect to the SQL ports 304 f , 304 g via a connection string or wire 316 a - 316 f . For example, if IIS “A” 107 a wishes to retrieve data in database “Z” 313 z then IIS “A” 107 a must create a wire between IIS port 304 b and SQL port 304 g . A wire is created by utilizing the correct connection string. Boxes 307 a , 307 z in FIG. 3 provide a description of the connection strings associated with the wires 316 a - 316 f . In the previous example, wire 316 b must use the connection string for database “Z” 313 z , as described in box 307 z , to create a connection between IIS “A” 107 a and SQL “Z” 310 z.
Generally, “ports” and “wires” store connection information between available resources within the network environment 100 . Ports 304 a - 304 g are abstract concepts of connection ports between two systems and are stored in shared memory 113 a , 113 z . Through a virtual topology, ports 304 a - 304 g provide a conceptual model for storing relevant information between systems. A port 304 a - 304 g may comprise of a plurality of wires 316 a - 316 f that are used with an appropriate protocol to make a connection to another port. Ports 304 a - 304 g allow global or local wire updates. Global wire updates affect all systems within the network environment 100 that use the updated port 304 a - 304 g . Local wire updates allow a particular port 304 a - 304 g on one system to be updated, while not updating other systems using the same port. For example, it may be necessary for a new target system 104 a to use a test server system 122 a for debugging. Accordingly, a local wire update can be used to change the port configuration of the new target system 104 a without affecting the similar port used by other systems. As described above, ports 304 a - 304 g are stored in shared memory 113 a , 113 z , therefore, ports can only be added or updated via the configuration data interface agent 110 a , 110 z.
Ports 304 a - 304 g contain various data elements including, but not limited to, port name, appropriate protocol, state, port type, and revision number. In the exemplary embodiment of the present invention, port names have a character limit, such as thirty-one characters, for increasing lookup speeds. Generally, there are two types of ports: client and server. Client ports belong to any system that acts as a client with regard to the resource wire to be connected. Likewise, server ports belong to any system that acts as a server (or is the destination) with regard to a resource wire to be connected. Client ports comprise wires 316 a - 316 f that the client system can use to connect. Server ports comprise wires 316 a - 316 f that the server system permits to connect. Preferably, the services 119 a , 119 z , 140 a , 140 z residing on the target systems 104 a , 104 z request resources on other systems and, therefore, utilize client ports. The state (or hint) of a port 304 a - 304 g include, but are not limited to, read, write, and dead. Read ports indicate that the associated wires are read-only. Write ports indicate that the associated wires are write-enabled. Dead ports indicate that all associated wires do not respond and cannot be used to create a successful connection. The appropriate protocol of a port 304 a - 304 g designates the type of protocol used by the port to make a connection. Appropriate protocols include, but are not limited to, hypertext transfer protocol (HTTP), tabular data stream protocol (TDS), server message block protocol (SMB), and remote procedure call protocol (RPC). Each port has only one port type and generally uses one appropriate protocol. The revision number changes when a wire within a port is added or updated. The revision number provides an immediate determination whether the port has been changed.
Wires 316 a - 316 f connect two ports together. The wires 316 a - 316 f contain allowable connection strings used by the ports 304 a - 304 g . Wires 316 a - 316 f contain various data elements including, but not limited to, wire id, wire value, and wire state. Generally, the wire id is an indexed integer value and the wire value is a string. Wire ids are only unique within a particular port 304 a - 304 g and, therefore, are not unique within the network environment 100 . The states of a wire 316 a - 316 f include, but are not limited to, read, write, and dead. Read wires indicate that the target resource is read-only. Write wires indicate that the target resource is write-enabled. Dead wires indicate that the wire does not respond and cannot be used to create a successful connection. Wires 316 a - 316 f are designated as dead when services 119 a , 119 z , 140 a , 140 z cannot connect to a server system 122 a , 122 z , 143 a , 143 z via the connection string. For example, the operator of the operator system 134 may designate a wire 316 a - 316 f as dead in the database 137 , which then propagates to the target systems 104 a , 104 z , the method described below.
In an alternative embodiment of the present invention, the target systems 104 a , 104 z further comprise a local service that periodically checks all of the local ports and tests all of the wires. Then, the local service may update the port and wire types automatically through the configuration data interface agent 110 a , 110 z . In yet another embodiment, the operator system 134 further comprises of a service that remotely checks all of the ports and tests all of the wires associated with the target systems 104 a , 104 z and server systems 122 a , 122 z , 143 a , 143 z . Accordingly, the service may then update the port and wire types in the database 137 , while the information propagates to the target systems 104 a , 104 z and server systems 122 a , 122 z , 143 a , 143 z.
FIG. 4 displays an example genre structure 400 in accordance with an exemplary embodiment of the present invention. In addition to storing ports and wires, the shared memory 113 a , 113 z stores and provides genre and record information for services 119 a , 119 b , 140 a , 140 z . In the exemplary embodiment of the present invention, genres represent runtime settings for services 119 a , 119 b , 140 a , 140 z and are not associated with connection ports, wires, or protocols. Accordingly, genres do not have states, protocols, or types. For example, and not limitation, a genre structure 400 may contain configuration data representing a unique identifier that allows a service 119 a , 119 b , 140 a , 140 z to determine whether the service is properly registered. Genre structures 400 include, but are not limited to, genre name and records. The genre name 401 is a string that labels and distinguishes genre structures 400 . In the exemplary embodiment of the present invention, genre names have a character limit, such as thirty-one characters. The character limit ensures that a fixed sized record can be used to represent the genre name and, thus, assists in increasing lookup speeds. The genre records 409 a - 409 e are indexed within the genre structure 400 by integer value ids 403 a - 403 e and include record values 406 a - 406 e . Generally, integer value ids 403 a - 403 e are only unique within the particular genre structure 400 . Unlike ports 304 a - 304 g and wires 316 a - 316 f , record values 406 a - 406 e may contain integer and/or string values. Additionally, genre structures 400 and ports 304 a - 304 g are stored in separate memory spaces within shared memory 113 a , 113 z.
FIG. 5 displays a block diagram representation illustrating a system for accessing configuration data in shared memory in accordance with an exemplary embodiment of the present invention. As described above with regard to FIG. 1 , services 119 a , 119 b , 119 c connect communicatively with the shared memory manager 116 a within a target system 104 a . In the exemplary embodiment of the present invention, the shared memory manager 116 a provides a plurality of read-only application programming interfaces (APIs) 501 , 504 , 507 , 510 , 513 , 515 for the services 119 a , 119 b , 119 c to access shared memory 113 a . The APIs 501 , 504 , 507 , 510 , 513 , 515 are generally housed in a dynamic link library (DLL) as part of the shared memory manager 116 a . The APIs 501 , 504 , 507 , 510 , 513 , 515 include, but are not limited to, getporthandle 501 , getport 504 , getwire 507 , getgenrehandle 510 , getgenre 513 , and getrecord 515 . In the exemplary embodiment of the present invention, the APIs are only accessible to services running on the local target system 104 a . The APIs 501 , 504 , 507 , 510 , 513 , 515 are more fully described below with regard to FIGS. 11-16 .
In the exemplary embodiment of the present invention, the shared memory 113 a includes, but is not limited to, an access control list 518 , service memory maps 521 a - 521 c, control memory 524 , and memory tables 527 a - 527 c . The access control list 518 includes, but is not limited to, service identifier information which verifies whether the service 119 a , 119 b , 119 c requesting information has permission to receive the requested data. For each service 119 a , 119 b , 119 c with access to the shared memory 113 a , there exists a service memory map 521 a , 521 b , 521 c . The service memory maps 521 a , 521 b , 521 c include, but are not limited to, a list of memory tables 527 a , 527 b , 527 c accessible to the requesting service 119 a , 119 b , 119 c . The control memory 524 includes, but is not limited, the physical location in memory that the memory tables 527 a , 527 b , 527 c reside. The memory tables 527 a , 527 b , 527 c include, but are not limited to, configuration data, ports, wires, genres, and records. The access control list 518 is connected communicatively with the service memory maps 521 a , 521 b , 521 c . The service memory maps 521 a , 521 b , 521 c include the memory tables 527 a , 527 b , 527 c in a contiguous memory space. Additionally, the control memory 524 is connected communicatively with the service memory maps 521 a , 521 b , 521 c and memory tables 527 a , 527 b , 527 c and is only used when the memory section is marked “dirty” and a service needs to find its updated memory section. In the exemplary embodiment of the present invention the memory tables 527 a , 527 b , 527 c are broken into sections, where each section can be controlled by the access control list 518 separately.
For example, and not limitation, service “A” 119 a may request port information for the printer 296 . Using the getport API 504 available through the shared memory manager 116 a via the DLL, service “A” 119 a sends a request to the shared memory 113 a . Generally, the shared memory manager 116 a ensures that the access control list 518 is associated with the correct memory sections. The operating system associated with the shared memory manager 116 a checks the identifier for service “A” 119 a and compares the identifier with a list of identifiers within the access control list 518 . Once a match has been determined, the operating system via the access control list 518 permits access to the shared memory manager 116 a which creates or accesses the service “A” memory map 521 a . If service “A” memory map 521 a does not list access to the requested port information, the shared memory manager 116 a refuses connection and returns a permission denied message. Otherwise, service “A” memory map 521 a accesses the appropriate memory table “C” 527 c for the requested port information. Finally, the shared memory 113 a returns the requested information retrieved from memory table “C” 527 c . If the memory section has been marked “dirty”, then a request from service “A” 119 a will access the control memory 524 which provides the location of the newly updated memory section.
FIG. 6 displays a block diagram representation illustrating memory tables 527 present in shared memory in accordance with an exemplary embodiment of the present invention. As discussed above, memory tables 527 provide appropriate data to services requesting such data. Memory table data includes, but is not limited to, port name, appropriate protocol, state, port type, revision number, wire id, wire value, wire state, genre name, integer value id, and record value. The control memory 524 lists all of the memory tables 527 available in a certain memory allocation. The memory table 527 comprises an invalid bit 601 a , 601 z , memory table control memory 604 a , 604 z , offset table 607 a , 607 z , key table 610 a , 610 z , value table 613 a , 613 z , and string pool 616 a , 616 z . The invalid bit 601 a , 601 z is used by the shared memory manager 116 a , 116 z , to mark old memory locations as invalid when new memory has been allocated and the original data has been moved to the new memory location. If the invalid bit 601 a , 601 z comprises any value other than zero, then the memory location is considered old and invalid. When a service 119 a , 119 z , 140 a , 140 z accesses a memory table 527 , the service 119 a , 119 z , 140 a , 140 z checks the invalid bit 601 a , 601 z to determine whether the data is still valid. If the invalid bit 601 a , 601 z indicates that the memory location is old, the service 119 a , 119 z , 140 a , 140 z can request the new memory location from the shared memory manager 116 a , 116 z . The memory table control memory 604 a , 604 z , provides general information concerning the memory table 527 . The ellipsis between memory table “A” 527 a and memory table “Z” 527 z illustrates that a plurality of memory tables may exist in the shared memory 113 a , 113 z and, therefore, the shared memory 113 a , 113 z is not limited to two memory tables as shown in FIG. 6 .
The memory table control memory 604 a , 604 z comprises multiple data elements including, but not limited to, keys, maxkeys, values, maxvalues, stringpool, and revision number. The offset table 607 a , 607 z provides offset data for relative memory addressing. Generally, the offset data provides a number that determines the starting point in memory of a particular element. Preferably, the offset table 607 a , 607 z assists in determining the appropriate starting address of certain keys in the key table 610 z , 610 z . The key table 610 z , 610 z comprises keys used as identifiers for a value or group of values. The keys are associated with particular values present in the value table 613 a , 613 z . The value table 613 a , 613 z comprises data type values or pointers to appropriate strings in the string pool 616 a , 616 z . Generally, pointers comprise the memory location of certain data instead of the actual data. The string pool 616 a , 616 z comprises a contiguous sequence of strings (such as alpha-numeric characters) with a pointer to the beginning of the string pool 616 a , 616 z and a pointer at the end of the string pool 616 a , 616 z . The accessing of data in the memory table 527 is described below with regard to FIG. 10 .
FIG. 7 displays a flowchart representation of a method of initializing shared memory 700 in accordance with an exemplary embodiment of the present invention. During initialization of a target system 104 a , 104 z the shared memory 1113 a , 113 z must be populated with appropriate data for the services 119 a , 119 z , 140 a , 140 z residing on the target system 104 a , 104 z . Such a population of data would be necessary after a reboot of a target system 104 a , 104 z . In the exemplary embodiment of the present invention, the operation controller 146 systematically checks target systems 104 a , 104 z for empty shared memory 113 a , 113 z.
After starting at step 701 , the method proceeds to step 704 where the operation controller 146 determines if the shared memory 113 a , 113 z of each target system 104 a , 104 z is populated with data. At step 707 the operation controller 146 verifies whether the particular shared memory 113 a , 113 z is populated. If so, the method ends at step 710 for the currently accessed shared memory 113 a , 113 z . The operation controller 146 then repeats the method of initializing shared memory 700 for the shared memory 113 a , 113 z of the next target system 104 a , 104 z . If the operation controller 146 determines at step 707 that the shared memory 113 a , 113 z is not populated, the method continues to step 713 . At step 713 , the operation controller 146 retrieves all appropriate data for the services 119 a , 119 z , 140 a , 140 z residing on the current target system 104 a , 104 z from the database 137 . Next, at step 716 , the operation controller 146 provides the retrieved data to the configuration data communication generator 128 . Then, at step 719 , the configuration data communication generator 128 converts the data into an appropriate communication for transfer to the target system 104 a , 104 z . Preferably, the configuration data communication generator 128 converts the data into appropriate XML code. Next, at step 722 , the configuration data communication generator 128 provides the communication to the configuration data interface agent 110 a , 110 z . The communication is sent by the configuration data communication generator 128 to the configuration data interface agent 110 a , 110 z via a secure communication link protected by a firewall 125 a , 125 b . A secure communication link can be established by encrypting any communication through the secure communication link using secure sockets layer (SSL). Using the communication provided by the configuration data communication generator 128 , the configuration data interface agent 110 a , 110 z , at step 725 , interprets the communication and updates the shared memory 113 a , 113 z via the shared memory manager 116 a , 116 z . The configuration data interface agent 110 a , 110 z provides the received data to the shared memory manager 116 a , 116 z which then updates the shared memory 113 a , 113 z , accordingly. Once the shared memory 113 a , 113 z has been initialized with data from the database 137 , the method ends at step 728 . The shared memory initialization method 700 may then be repeated until all of the target systems 104 a , 104 z have populated shared memory 113 a , 113 z.
FIG. 8 displays a pseudo-code representation 800 for writing or updating configuration data in shared memory in accordance with an exemplary embodiment of the present invention. As discussed above, the configuration data communication generator 128 generates a communication containing data from the database 137 to send to the configuration data interface agent 110 a , 110 z via a secured connection. In the exemplary embodiment of the present invention, the communication generated by the configuration data communication generator 128 is XML code. XML provides customizable tags that permit the definition, validation, transmission, and interpretation of data between a plurality of systems. Generally, tags 801 - 825 , 804 b - 825 b are commands used within a document or code that indicates how the portion of a document or code should be formatted or interpreted. One skilled in the art will recognize that XML is derived from standard generalized markup language (SGML) and provides a widely-accepted code format for communication between systems.
The XML tag 801 indicates the beginning of XML code. Generally, tags 801 - 825 are paired and include a beginning tag and an ending tag. The beginning tag is often represented by a tag name between a less than (“<”) and greater than (“>”) symbol. The ending tag is usually identical to the beginning tag except that after the less than symbol (“<”) there is a forward slash (“/”). For example, and not limitation, the beginning envelope tag 804 is represented in FIG. 8 as “<Envelope>”. The corresponding ending envelope tag 804 b is represented in FIG. 8 as “</Envelope>”. Everything in between the beginning envelope tag 804 and the ending envelope tag 804 b is interpreted as part of the envelope element. Likewise, all characters between the beginning body tag 807 and the ending body tag 807 b represent the body of the envelope. The jukebox tags 810 , 810 b indicate that the information between the beginningjukebox tag 810 and the endingjukebox tag 810 b is data to be used to update shared memory 113 a , 113 z . Accordingly, the genre tags 813 , 813 b provide genre data, the record tags 816 , 819 , 816 b , 819 b provide record data in string and integer formats, the port tags 822 , 822 b provide port data, and the wire tags 825 , 825 b provide wire data. The configuration data interface agent 110 a , 110 z parses the XML code sent by the configuration data communication generator 128 to extract genre, record, port, and wire data to update the shared memory 113 a , 113 z via the shared memory manager 116 a , 116 z.
FIGS. 9A-9B display a flowchart representation of a method of updating or adding configuration data in shared memory 900 in accordance with an exemplary embodiment of the present invention. As discussed above, when the configuration data interface agent 110 a , 110 z receives a communication to update or add data to the shared memory 113 a , 113 z from the configuration communication generator 128 , the configuration data interface agent 110 a , 110 z provides the shared memory manager 116 a , 116 z with data to be added or updated in shared memory 113 a , 113 z . To make such an update or addition, the shared memory manager 116 a , 116 z must determine if the current memory space is large enough to include the new additions and updates.
After starting at step 901 , the shared memory manager 116 a , 116 z , at step 904 , checks the current memory allocation for the shared memory 113 a , 113 z and determines whether additional memory space is needed. If so, at step 910 , the shared memory manager 116 a , 116 z allocates the appropriately-sized memory space in shared memory 113 a , 113 z . In the exemplary embodiment of the present invention, the shared memory manager 116 a , 116 z creates a log entry when additional memory is allocated (not shown). The shared memory manager 116 a , 116 z copies all of the memory tables 527 from the old memory space to the new memory space in a “bottom-up” approach. The “bottom-up” approach entails copying the lowest level of the memory table 527 first before moving on to the higher levels. This approach assists in memory management by allowing updates and additions without having to lock the original memory table 527 . Therefore, services 119 a , 119 z , 140 a , 140 z will not be waiting for updates during runtime. Next, at step 913 , the shared memory manager 1116 a , 116 z copies data from the string pool 616 a , 616 z in the old memory space to the newly allocated memory space, if necessary. Additionally, at step 913 , the shared memory manager 116 a , 116 z may add or update the string pool 616 a , 616 z with new data received from the configuration data interface agent 110 a , 110 z . Then, at step 916 , the shared memory manager 116 a , 116 z copies data from the value table 613 a , 613 z in the old memory space to the newly allocated memory space, if necessary. Also, at step 916 , the shared memory manager 116 a , 116 z may add or update the value table 613 a , 613 z with new data received from the configuration data interface agent 110 a , 110 z or may add or update pointers to the string pool 616 a , 616 z . Next, at step 919 , the shared memory manager 116 a , 116 z copies data from the key table 610 a , 610 z in the old memory space to the newly allocated memory space, if necessary. Additionally, at step 919 , the shared memory manager 116 a , 116 z may add or update the key table 610 a , 610 z with new data received from the configuration data interface agent 110 a , 110 z . Then, at step 922 , the shared memory manager 116 a , 116 z copies data from the offset table 607 a , 607 z in the old memory space to the newly allocated memory space, if necessary. Also, at step 922 , the shared memory manager 116 a , 116 z may add or update the offset table 607 a , 607 z with new data received from the configuration data interface agent 110 a , 110 z . Next, at step 925 , the shared memory manager 116 a , 116 z copies data from the memory table control memory 604 a , 604 z in the old memory space to the newly allocated memory space, if necessary. Additionally, at step 925 , the shared memory manager 116 a , 116 z may add or update the memory table control memory 604 a , 604 z with new data received from the configuration data interface agent 110 a , 110 z . At step 928 , the revision number for the memory table 527 in the new allocation space is incremented. Incrementing the revision number of a memory table 527 , notifies services 119 a , 119 z , 140 a , 140 z that use the memory table 527 that a change has occurred and it will be necessary to re-cache the memory table 527 into the service's memory space. Once the memory table 527 has been copied to the newly allocated memory, at step 931 , the invalid bit 601 a , 601 z of the memory table 527 in the old memory space is marked. Marking the invalid bit 601 a , 601 z in the old memory space notifies services 119 a , 119 z , 140 a , 140 z that the data at the old memory location has moved to a new memory allocation. Therefore, the services 119 a , 119 z , 140 a , 140 z will need to access the data from the new memory space. Steps 913 , 916 , 919 , 922 , 925 , 928 , 931 may be repeated by the shared memory manager 116 a , 116 z as necessary to copy all of the memory tables 527 into the new memory allocation. After the shared memory manager 116 a , 116 z copies all of the appropriate memory tables 527 into the new memory space the method ends at step 934 .
If at step 904 additional memory space is not needed, then the method 900 continues to step 907 where the shared memory manager 116 a , 116 z determines the position in memory to update or add the data. As noted above, the shared memory manager 116 a , 116 z updates and adds data to the memory table 527 in a “bottom-up” approach. At step 937 , the shared memory manager 116 a , 116 z updates or adds data received from the configuration data interface agent 110 a , 110 z in the string pool 616 a , 616 z , if necessary. As mentioned above, the string pool 616 a , 616 z is a collection of strings containing pointers at the beginning and end of the string pool 616 a , 616 z . Therefore, at step 940 , the shared memory manager 116 a , 116 z may update the string pointers, if necessary, to facilitate an addition to the string pool 616 a , 616 z . Next, at step 943 , the shared memory manager 116 a , 116 z updates or adds data received from the configuration data interface agent 110 a , 110 z in the value table 613 a , 613 b , if necessary. Then, at step 946 , the shared memory manager 116 a , 116 z updates or adds data received from the configuration data interface agent 110 a , 110 z in the key table 610 a , 610 z , if necessary. The method 900 then moves to step 949 , where the shared memory manager 116 a , 116 z updates or adds data received from the configuration data interface agent 110 a , 110 z in the offset table 607 a , 607 z , if necessary. Next, at step 952 , the shared memory manager 116 a , 116 z updates or adds data received from the configuration data interface agent 110 a , 110 z in the memory table control memory 604 a , 604 z , if necessary. Finally, at step 955 , the revision number of the memory table 527 is incremented by the shared memory manager 116 a , 116 z to alert services 119 a , 119 z , 140 a , 140 z that the memory table 527 has changed contents. The method 900 ends at step 934 . If the shared memory manager 116 a , 116 z adds a new memory table 527 , instead of adding or updating data in a memory table 527 , then the shared memory manager 116 a , 116 z may update the control memory 524 in the memory space to indicate a new memory table 527 has been created (not shown). Using the “bottom-up” approach, the control memory 524 in the memory space would be updated after the new memory table 527 had been created.
FIGS. 10A-10C display a flowchart representation of a method of accessing data from shared memory 1000 in accordance with an exemplary embodiment of the present invention. Recall that when accessing the shared memory 113 a , 113 z , the shared memory manager 116 a , 116 z via the access control list 518 determines whether the service 119 a , 119 z , 140 a , 140 z has permission to access the requested data. After starting the method of accessing data in shared memory 1000 , at step 1001 , the shared memory manager 116 a , 116 z , at step 1004 , receives a request from a service 119 a , 119 z , 140 a , 140 z and the identifier associated with the service 119 a , 119 z , 140 a , 140 z . At step 1007 , the operating system associated with the shared memory manager 116 a , 116 z compares the received identifier with the permitted identifiers listed in the access control list 518 . Next, at step 1010 , the operating system determines if the service 119 a , 119 z , 140 a , 140 z has permission to access the requested data. Generally, the operating system determines whether the service 119 a , 119 z , 140 a , 140 z has permission to access the port 304 a - 304 g or genre 400 that contains the requested data. If the operating system matches the service identifier in the access control list 518 and the memory table 527 containing the requested data is found in the appropriate service memory map 521 a , 521 b , 521 c , then the service 119 a , 119 z , 140 a , 140 z has permission to access the data. Otherwise, the service 119 a , 119 z , 140 a , 140 z does not have access to the data and the method 1000 continues to step 1013 . At step 1013 , the shared memory manager 116 a , 116 z returns a permission denied message to the service 119 a , 119 z , 140 a , 140 z that requested access to the data. Once the permission denied message has been sent, the method 1000 ends at step 1016 .
If, however, at step 1010 , the operating system determines that the service does have access to the requested data, then the shared memory manager 116 a , 116 z determines whether the requested port 304 a - 304 g or genre 400 exists, at step 1019 . If no memory table 527 exists for the requested port 304 a - 304 g or genre 400 , then, at step 1022 , the shared memory manager 116 a , 116 z sends a message to the error log that the requested port 304 a - 304 g or genre 400 was not found. Next, at step 1067 , the shared memory manager 116 a , 116 z returns an error message to the service 119 a , 119 z , 140 a , 140 z requesting the data. The method 1000 would then end, at step 1073 .
If, at step 1019 , the shared memory manager 116 a , 116 z determines that the port 304 a - 304 g or genre 400 exists, then the method 1000 continues to step 1025 . At step 1025 , the service 119 a , 119 z , 140 a , 140 z determines whether it is caching the wire 316 a - 316 f and record 409 a - 409 e data. The service 119 a , 119 z , 140 a , 140 z comprises information including, but not limited to, the request data (such as the port, genre, wire, or record), the service identifier, caching status, and cached revision number. The caching status identifies whether the requesting service 119 a , 119 z , 140 a , 140 z is caching wires 316 a - 316 f or records 409 a - 409 e.
If, at step 1025 , the service 119 a , 119 z , 140 a , 140 z determines that it is not caching the wire 316 a - 316 f and record 409 a - 409 e data, then the service 119 a , 119 z , 140 a , 140 z , at step 1031 , attempts to read the requested data from shared memory 113 a , 113 z . The method 1000 then continues to step 1040 , discussed below.
Otherwise, if at step 1025 the service 119 a , 119 z , 140 a , 140 z determines that it is caching the wire 316 a - 316 f and record 409 a - 409 e data, then the service 119 a , 119 z , 140 a , 140 z , at step 1028 , compares its cached revision number with the appropriate revision number in shared memory 113 a , 113 z . As discussed above, the revision number in shared memory 113 a , 113 z is stored in the port 304 a - 304 g or genre 400 memory table 527 . Next, at step 1034 , the service 119 a , 119 z , 140 a , 140 z determines whether the appropriate revision number read from shared memory 113 a , 113 z is greater than its cached revision number. If so, at step 1037 , the service 119 a , 119 z attempts to retrieve the requested data from shared memory 113 a , 113 z and, if successful, the service 119 a , 119 z , 140 a , 140 z refreshes its cache. Next, the method 1000 continues to step 1040 , discussed below.
If, however, at step 1034 , the service 119 a , 119 z , 140 a , 140 z determines that the appropriate revision number is not greater than its cached revision number, then the method 1000 continues to step 1049 , discussed below.
When the method 1000 reaches step 1040 , the service 119 a , 119 z , 140 a , 140 z determines whether the requested wire 316 a - 316 f or record 409 a - 409 e is dead. Records 409 a - 409 e do not typically have a status and thus would never be dead. Therefore, if the service 119 a , 119 z , 140 a , 140 z was requesting record 409 a - 409 e data, the method 1000 would continue to step 1049 . As discussed above, wires 316 a - 316 f contain a wire status that can be read, write, or dead. If the service 119 a , 119 z , 140 a , 140 z determines that the wire 316 a - 316 f status is dead, the method 1000 continues to step 1043 . At step 1043 , the service 119 a , 119 z , 140 a , 140 z errors out without waiting for a time-out from the requested resource. The method 1000 then ends at step 1046 . If, however, at step 1040 , the service 119 a , 119 z , 140 a , 140 z determines that the wire 316 a - 316 f is not dead, the method continues to step 1049 .
When the method 1000 reaches step 1049 , the service 119 a , 119 z , 140 a , 140 z determines whether the requested data is wire data or record data. If the requested data is not wire data, then the service retrieves the record data from the service cache. The method 1000 then ends at step 1076 . Otherwise, if, at step 1049 , the service 119 a , 119 z , 140 a , 140 z determines that the requested data is wire data, then the service 119 a , 119 b , 140 a , 140 z connects using the cached wire data, at step 1052 .
Next, at step 1055 , the service 119 a , 119 b , 140 a , 140 z will either make a successful connection or the connection will fail. If the connection fails, the method 1000 continues to step 1061 where the service 119 a , 119 z , 140 a , 140 z logs the connection error and logs the wire 316 a - 316 f as dead in the error log. Then, at step 1067 , the service 119 a , 119 z , 140 a , 140 z returns an error message to the client making the service request. The method 1000 then ends at step 1073 . If, however, at step 1055 the connection is successful, then a connection is established, at step 1064 , for the service 119 a , 119 z , 140 a , 140 z . Then, at step 1070 , the service 119 a , 119 z , 140 a , 140 z returns a connection success message to the client making the service request. The method 1000 then ends at step 1073 .
FIGS. 11-16 display flowchart representation of methods representing the APIs in an exemplary embodiment of the present invention as discussed above with reference to FIG. 5 . Specifically, FIG. 11 displays a flowchart representation of a method of accessing port-handle information 1100 in accordance with an exemplary embodiment of the present invention. After starting at step 1101 , the method 1100 proceeds to step 1104 where the shared memory manager 116 a , 116 z receives a getporthandle request from a service 119 a , 119 z , 140 a , 140 z . At step 1107 , the shared memory manager 116 a , 116 z accesses the offset table 607 a , 607 z of the appropriate memory table 257 containing the requested port 304 a - 304 g . Using a hash table, the shared memory manager 116 a , 116 z can use a getporthandle parameter (such as the port name) to access the appropriate offset table 607 a , 607 z . Next, at step 1110 , the shared memory manager 116 a , 116 z accesses the appropriate key table 610 a , 610 z via the offset data. As discussed above, the offset data assists in determining the appropriate starting address of appropriate keys in the key table 610 z , 610 z . Then, at step 1113 , the shared memory manager 116 a , 116 z determines the appropriate key or keys in the key table 610 a , 610 z . Typically, the key is used to create a handle so that data can be accessed directly from the memory table 527 without having to access the hash algorithm or offset table 607 a , 607 z . Next, at step 1116 , the shared memory manager 116 a , 116 z returns the porthandle pointer generated from the key table 610 a , 610 z to the requesting service 119 a , 119 z , 140 a , 140 z . The method 1100 then ends at step 1119 .
FIG. 12 displays a flowchart representation of a method of accessing genre-handle information 1200 in accordance with an exemplary embodiment of the present invention. After starting at step 1201 , the method 1200 proceeds to step 1204 where the shared memory manager 116 a , 116 z receives a getgenrehandle request from a service 119 a , 119 z , 140 a , 140 z . At step 1207 , the shared memory manager 116 a , 116 z accesses the offset table 607 a , 607 z of the appropriate memory table 257 containing the requested genre 400 . Using a hash table, the shared memory manager 116 a , 116 z can use a getgenrehandle parameter (such as the genre name) to access the appropriate offset table 607 a , 607 z . Next, at step 1210 , the shared memory manager 116 a , 116 z accesses the appropriate key table 610 a , 610 z via the offset data. Then, at step 1213 , the shared memory manager 116 a , 116 z determines the appropriate key or keys in the key table 610 a , 610 z . As discussed above, the key is used to create a handle so that data can be accessed directly from the memory table 527 without having to access the hash algorithm or offset table 607 a , 607 z . Next, at step 1216 , the shared memory manager 116 a , 116 z returns the genrehandle pointer generated from the key table 610 a , 610 z to the requesting service 119 a , 119 z , 140 a , 140 z . The method 1200 then ends at step 1219 .
FIG. 13 displays a flowchart representation of a method of accessing port information 1300 in accordance with an exemplary embodiment of the present invention. After starting at step 1301 , the method 1300 proceeds to step 1304 where the shared memory manager 116 a , 116 z receives a getport request from a service 119 a , 119 z , 140 a , 140 z . Next, at step 1307 , the shared memory manager 116 a , 116 z accesses the offset table 607 a , 607 z by using a hash algorithm. The shared memory manager 116 a , 116 z may use a getport parameter (such as the port name) to access the appropriate offset table 607 a , 607 z via the hash algorithm. Then, at step 1310 , the shared memory manager 116 a , 116 z accesses the key table 610 a , 610 z via the offset data retrieved from the offset table 607 a , 607 z . The method 1300 then proceeds to step 1313 where the shared memory manager 116 a , 116 z determines the appropriate keys in the key table 610 a , 610 z . Next, at step 1316 , the shared memory manager 116 a , 116 z accesses the corresponding values in the value table 613 a , 613 z based on the keys retrieved in the key table 610 a , 610 z . If the values in the value table 613 a , 613 z comprise of pointers that point to the string pool 616 a , 616 z , then the method 1300 proceeds to step 1319 where the shared memory manager 116 a , 116 z retrieves the appropriate data from the string pool 616 a , 616 z via the values retrieved from the value table 613 a , 613 z . Next, at step 1322 , the shared memory manager 116 a , 116 z returns appropriate port data from the string pool 616 a , 616 z to the requesting service 119 a , 1119 z , 140 a , 140 z . The method 1300 then ends at step 1325 . In another embodiment of the present invention, if the getport request uses a porthandle, then steps 1307 and 1310 may be omitted.
FIG. 14 displays a flowchart representation of a method of accessing wire information 1400 in accordance with an exemplary embodiment of the present invention. After starting at step 1401 , the method 1400 proceeds to step 1404 where the shared memory manager 116 a , 116 z receives a getwire request from a service 119 a , 119 z , 140 a , 140 z . Next, at step 1407 , the shared memory manager 116 a , 116 z accesses the offset table 607 a , 607 z by using a hash algorithm. The shared memory manager 116 a , 116 z may use a getwire parameter (such as the port name) to access the appropriate offset table 607 a , 607 z via the hash algorithm. Then, at step 1410 , the shared memory manager 116 a , 116 z accesses the key table 610 a , 610 z via the offset data retrieved from the offset table 607 a , 607 z . The method 1400 then proceeds to step 1413 where the shared memory manager 116 a , 116 z determines the appropriate keys in the key table 610 a , 610 z . Next, at step 1416 , the shared memory manager 116 a , 116 z accesses the corresponding values in the value table 613 a , 613 z based on the keys retrieved in the key table 610 a , 610 z . If the values in the value table 613 a , 613 z comprise of pointers that point to the string pool 616 a , 616 z , then the method 1400 proceeds to step 1419 where the shared memory manager 116 a , 116 z retrieves the appropriate data from the string pool 616 a , 616 z via the values retrieved from the value table 613 a , 613 z . Next, at step 1422 , the shared memory manager 116 a , 116 z returns the appropriate wire data from the string pool 616 a , 616 z to the requesting service 119 a , 119 z , 140 a , 140 z . The method 1400 then ends at step 1425 . In another embodiment of the present invention, if the getwire request uses a porthandle, then steps 1407 and 1410 may be omitted.
FIG. 15 displays a flowchart representation of a method of accessing genre information 1500 in accordance with an exemplary embodiment of the present invention. After starting at step 1501 , the method 1500 proceeds to step 1504 where the shared memory manager 116 a , 116 z receives a getgenre request from a service 119 a , 119 z , 140 a , 140 z . Next, at step 1507 , the shared memory manager 116 a , 116 z accesses the offset table 607 a , 607 z by using a hash algorithm. The shared memory manager 116 a , 116 z may use a getgenre parameter (such as the genre name) to access the appropriate offset table 607 a , 607 z via the hash algorithm. Then, at step 1510 , the shared memory manager 116 a , 116 z accesses the key table 610 a , 610 z via the offset data retrieved from the offset table 607 a , 607 z . The method 1500 then proceeds to step 1513 where the shared memory manager 116 a , 116 z determines the appropriate keys in the key table 610 a , 610 z . Next, at step 1516 , the shared memory manager 116 a , 116 z accesses the corresponding values in the value table 613 a , 613 z based on the keys retrieved in the key table 610 a , 610 z . If the values in the value table 613 a , 613 z comprise of pointers that point to the string pool 616 a , 616 z , then the method 1500 proceeds to step 1519 where the shared memory manager 116 a , 116 z retrieves the appropriate data from the string pool 616 a , 616 z via the values retrieved from the value table 613 a , 613 z . Next, at step 1522 , the shared memory manager 116 a , 116 z returns the appropriate genre data from the string pool 616 a , 616 z to the requesting service 119 a , 119 z , 140 a , 140 z . The method 1500 then ends at step 1525 . In another embodiment of the present invention, if the getgenre request uses a genrehandle, then steps 1507 and 1510 may be omitted.
FIG. 16 displays a flowchart representation of a method of accessing record information 1600 in accordance with an exemplary embodiment of the present invention. After starting at step 1601 , the method 1600 proceeds to step 1604 where the shared memory manager 116 a , 116 z receives a getrecord request from a service 119 a , 119 z , 140 a , 140 z . Next, at step 1607 , the shared memory manager 116 a , 116 z accesses the offset table 607 a , 607 z by using a hash algorithm. The shared memory manager 116 a , 116 z may use a getrecord parameter (such as the genre name) to access the appropriate offset table 607 a , 607 z via the hash algorithm. Then, at step 1610 , the shared memory manager 116 a , 116 z accesses the key table 610 a , 610 z via the offset data retrieved from the offset table 607 a , 607 z . The method 1600 then proceeds to step 1613 where the shared memory manager 1116 a , 116 z determines the appropriate keys in the key table 610 a , 610 z . Next, at step 1616 , the shared memory manager 116 a , 116 z accesses the corresponding values in the value table 613 a , 613 z based on the keys retrieved in the key table 610 a , 610 z . If the values in the value table 613 a , 613 z comprise of pointers that point to the string pool 616 a , 616 z , then the method 1600 proceeds to step 1619 where the shared memory manager 116 a , 116 z retrieves the appropriate data from the string pool 616 a , 616 z via the values retrieved from the value table 613 a , 613 z . Next, at step 1622 , the shared memory manager 116 a , 116 z returns the appropriate record data from the string pool 616 a , 616 z to the requesting service 119 a , 119 z , 140 a , 140 z . The method 1600 then ends at step 1625 . In another embodiment of the present invention, if the getrecord request uses a genrehandle, then steps 1607 and 1610 may be omitted.
Whereas the present invention has been described in detail it is understood that variations and modifications can be effected within the spirit and scope of the invention, as described herein before and as defined in the appended claims. The corresponding structures, materials, acts, and equivalents of all means plus function elements, if any, in the claims below are intended to include any structure, material, or acts for performing the functions in combination with other claimed elements as specifically claimed. | A system and methods for sharing configuration information with multiple services, or processes, via shared memory. The configuration information, typically, comprises runtime information utilized by processes during operation, including without limitation, information describing data communication connections between the local computer and other computing resources (i.e., port and wire information), and information defining numeric values or character string values (i.e., genre and record information). The system architecture includes a plurality of APIs which: reside at the local computer; populate, manage, and control access to a shared memory containing the configuration information; and, are executable only by processes executing at the local computer, thereby limiting access to the shared memory. Access to the configuration information is further limited to only those processes identified as having appropriate permission. The methods enable the configuration information of the shared memory to be modified during local computer operation and without impeding access to the configuration information. | 8 |
BACKGROUND OF THE INVENTION
[0001] This invention relates to semiconductor wafer processing, and more particularly to a semiconductor wafer susceptor which can be used in batch processing of semiconductor substrates.
[0002] For common semiconductor films such as silicon nitride, polysilicon, and thermal oxides, substrate processing usually proceeds by elevating the substrate to some process temperature, conducting the process, and finally cooling the substrate. Generally, most processes are conducted in a 200 mm batch furnace where substrates (hereafter referred to as wafers) are placed in a vertically stacked arrangement. Because of process and throughput requirements, the wafer stack often undergoes rapid heating and cooling at the beginning and end of the process. However, some thermal ramping limits exist at higher processing temperatures. It is now known that for 300 mm wafer, serious limitations exist on wafer heating/cooling rates and maximum process temperatures, well below the operational limits of the processing equipment.
[0003] The gravitational force and elevated process temperature (typically above 850° C.) cause considerable stress on the silica on wafer, leading to situations where slip and plastic deformation may occur. Fast thermal ramping can further degrade the situation because within-wafer (WinW) thermal gradients from uneven heating of wafers in a vertical stacked arrangement may cause slip to occur even before the process temperature is reached. Of course, fast thermal ramping is employed to increase productivity by decreasing the overall cycle time or reduce thermal budget by decreasing the ramping cycles. Therefore, a serious situation arises for high temperature processing of 300 mm substrate, especially in batch processing environments. Additionally, even if slip does not occur, the induced thermal gradient on the wafer may be of sufficient magnitude as to cause significant differences in the thermal histories of the die spread across the wafer. This will result in an unexpected die performance variation between the wafer center and edge locations.
[0004] Two approaches can be taken to solve this slip problem. One approach is to improve the wafer's chemical and mechanical characteristics, such as decreasing the oxygen precipitate concentration within the silicon wafer. This approach is an area of responsibility for the wafer manufacturers. The other approach is to improve the substrate support design.
[0005] The current industry standard for vertical batch wafer processing is the ladder boat and its variations (FIG. 1). This is the simplest design for vertical batch processing. However, it does not provide the most optimum mechanical support possible with respect to gravitational forces. Also, the standard ladder boat provides little reduction in thermal gradients. The ladder boat's greatest advantages are its low cost and compatibility with standard automation.
[0006] Two previously developed innovations have addressed the WinW wafer thermal issue for batch processing. The first wafer support method, shown in FIG. 2, was developed and patented by Tokyo Electron Ltd. (TEL). This “ring” support method uses a ring of material (typically quartz) designed to come into physical contact with the edge of the wafer. The addition of mass near or at the wafer's edge reduces the WinW thermal gradient because of the increase in heat capacity and change in radiation view factors. The method also provides a larger area of mechanical support than a ladder boat. The method gives good performance on 200 mm wafers, as thermal WinW gradients are controlled to under 10° C. for fast thermal ramps (above 75° C./min). However, this support method is complex and such designs are more expensive to manufacture and purchase. Additionally, this method requires more complex automation to load and unload wafers from the support appliance, leading to added cost for the associated support automation.
[0007] Another approach found in the prior art (previously patented by SVG, Thermco Systems) is the “band” method as shown in FIG. 3. Here, a thin band of material, typically quartz, is placed around the edge of the wafer, but not in intimate contact. The quartz material is either opaque or mechanically modified to be translucent. This method, like the ring support, reduces or screens incident radiation onto the wafer's edge, while permitting radiation through the unblocked areas and onto the wafer's center. Although not as effective as the ring support method shown in FIG. 2, the “band” method does reduce WinW thermal gradients and can be manufactured at a lower cost.
[0008] Other approaches to wafer support methodologies have been previously explored by others and are well known within the industry. In FIG. 4A, the best theoretical point contact support at a single radius value is shown. This method places point supports at 70% of the radial distance from the center to the wafer's edge, to balance the weight of the wafer on either side of the support and reduce gravitational stress effects. This approach when implemented in a ladder boat configuration will provide better support, but the cost will be greater due to the additional manufacturing complexity of very long support tabs. Also, this method does not address the WinW thermal gradient problem. A corresponding analogy exists for the ring support (point contact) where the location for a single ring would be also at 70% of the radial distance from the center to the wafer's edge. In this case, the ring support's axial symmetry greatly improves the control of the gravitational stress magnitude and symmetry compared to the ladder boat method. FIG. 4C shows the absolute best theoretical support design possible, as all pints on the wafer are mechanically supported. Clean, simple, and efficient mechanical wafer loading and unloading for this design becomes a serious problem, if not impossible, with current automation technology.
[0009] The vast majority of single wafer processing equipment currently use supports shown in FIGS. 4B and 4C. Here either a ring of material or a flat plate or susceptor composed of quartz, SiC or similar material supports the wafer. These design are preferred for reasons of simplicity or reduction of thermal mass to permit rapid wafer heating and cooing (up to 100° C./sec). The supports in FIGS. 4B and 4C are not necessarily employed for thermal WinW control in single wafer processing equipment because they rely on heating element design to accomplish WinW thermal uniformity. In some cases, there~may be some benefit based on material selection with reducing thermal non-uniformity. As an added benefit, gravitational forces are reduced and in the case of FIG. 4C, are completely eliminated if the right support material is used. However, these designs do add complexity to the method of wafer handling and are best suited for single wafer environments where the automation comprises a larger percentage of the overall equipment set and cost.
[0010] WinW Thermal Gradients
[0011] The primary issue with batch processing and rapid heating of large substrates is the resultant thermal gradients, as demonstrated in FIG. 5. During the heating phase of the process cycle (see FIG. 5A), the edges of the wafer receive the majority of the incident radiation and as a result heat up at a faster rate. Heating of the interior regions of the wafer is chiefly accomplished by thermal conduction through the substrate itself. As a result, a “bowl”-shaped thermal profile forms across the wafer. This thermal gradient can add to the gravitational stress and—if large enough—cause warping, bowing, plastic deformation, and slip to occur. A solution to this problem would be to increase the pitch of the wafer stack, thereby increasing the radiation view factor for the wafer center.
[0012] As in the case for heating, rapid cooling of the wafer (see FIG. 5B) can also have negative effects. Efficient radiative cooling of the wafer's edge occurs because of a large exposed area (large angular exposure to the heater walls) at the wafer's edge. The interior regions of the wafer have smaller exposed angular area to the outside and thus cool inefficiently through radiation. The central region of the wafer mainly cools through thermal conduction from the wafer center to the edge where then energy is more effectively radiated away. As a result, a “dome”-like thermal gradient is formed across the wafer. This thermal gradient can add to the gravitational stress and—if large enough—cause warping, bowing, plastic deformation, and slip to occur. Like heating, a solution would be to increase the radiation view factor for the wafer center.
[0013] Given a particular support design, the magnitude of this WinW thermal gradient coupled with the process temperature determines whether slip conditions exist. FIG. 6 shows the difference in slip curves between a ladder-type and a ring boat. For a given WinW thermal gradient and process temperature, the wafer will tend to exhibit slip if the process condition lies on the right-hand side of the slip curve. FIG. 6 shows that the maximum allowable delta T decreases rapidly with increasing wafer edge temperature.
[0014] As seen in FIG. 7, the ladder boat (3point support) would not be sufficient for processes requiring temperatures above 850° C., as slip and possible plastic deformation would occur. Increasing the number of point supports for a ladder boat or decreasing the oxygen precipitate concentration would help. Increasing the number of point supports and relocating them to the optimum locations would shift the slip curve to the right and permit a larger allowable WinW thermal gradient the processing temperature. The disk and ring supports lie near the limit for such improvements. The ring boat (ring support) would be adequate for the high temperature processes, but the complexity of wafer automation would be a disadvantage.
SUMMARY OF THE INVENTION
[0015] The present invention relates to a semiconductor wafer susceptor that is used in supporting substrates in batch processing. In FIG. 8, the approach suggested is to provide a susceptor design that is generally flat and makes contact with the majority of the wafer as to eliminate the gravitational stress component. The new susceptor design is thin in cross section, on the order of the wafer thickness itself (˜750 microns) and thus adds minimal mass to the thermal load. The susceptor is composed of a material or composite with a higher thermal conductivity than Si, such as SiC. It mostly resembles a flattened “top hat” in shape, extends beyond the edge 11 of the wafer 12 , and has two planes, a primary plane 13 and a secondary plane 15 , or primary flat surfaces, thus the name extended bi-planar susceptor.
[0016] Another feature of the bi-planar shape is that the edge 14 of the susceptor 10 is not in intimate contact with the edge 11 of the wafer 12 . Also, the edge of the susceptor extends beyond that of the wafer. This design feature is best explained as follows, refer to FIGS. 9 and 10 for graphical illustrations of discussion below.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] The various advantages of the present invention will become apparent to one skilled in the art by reading the following specification and subjoined claims and by referencing the following drawings in which:
[0018] [0018]FIG. 1 is an industry standard for wafer support, the three rail vertical ladder boat, (A) cross-section showing the effect of gravity, (B) top view, and (C) vertical stack arrangement;
[0019] [0019]FIG. 2 is a ring boat: a ring supports the wafer along and near the wafer's edge, (A) cross-section, (B) top view, and (C) vertical stack arrangement;
[0020] [0020]FIG. 3 is a band support design which places an opaque quartz band near the wafer's edge, (A) cross section, (B) top view, and (C) vertical stack arrangement;
[0021] [0021]FIG. 4 is an optimal support design, (A) best support method, (B) support ring used on some single wafer systems, (C) flat susceptor design used on some single wafer systems;
[0022] [0022]FIG. 5 is an illustration of the within-wafer thermal gradients during heating and cooling of the substrates;
[0023] [0023]FIG. 6 illustrates slip curves for ladder-type boat (3 point support) and ring boat (point contact support);
[0024] [0024]FIG. 7 is a slip performance by support method chart;
[0025] [0025]FIG. 8 is a wafer support design of the claimed invention;
[0026] [0026]FIG. 9 illustrates expected improvement in within-wafer thermal gradient;
[0027] [0027]FIG. 10, key regions of heat transfer for the claimed invention;
[0028] [0028]FIG. 11 illustrates calculated view angles for radial positions using the design of the claimed invention; and
[0029] [0029]FIG. 12, an alternative embodiment of the claimed invention.
DETAILED DESCRIPTION OF THE INVENTION
[0030] In FIG. 8, a semiconductor wafer susceptor 10 is shown with a substrate wafer 12 placed on top. The design is such that an edge 14 of the susceptor 10 is not in contact with the wafer 12 . This permits the susceptor 10 to collect 50% (or more) of the radiation incident at the wafer's edge 11 without transmitting the energy directly to the wafer's edge 11 . Instead the energy collected in Region I and II which includes a plurality of flat annular extensions 17 in secondary plane 19 , is carried away from the wafers edge 11 and transferred through conduction into Region III, a flat circular central region 18 situated in primary plane 15 . There, this additional thermal energy is distributed through improved thermal conduction of the susceptor material across the central region 18 of the wafer 12 . The amount of collection is strongly modulated by the length of Region I beyond the wafer's edge 11 . The point at which the collected thermal energy is first injected in the wafer 12 is determined by the Region II/III interface.
[0031] The susceptor 10 contact the majority of the wafer 12 at central region 18 , a distribution plate. This region 18 provides the best mechanical support possible for the majority of the wafer 12 (a generally flat plate), thus eliminating virtually all effects from gravitational stress. Also, since the susceptor material is of a higher thermal conductivity than Si, the heat distribution in Region III (central region 18 ) which is mainly controlled by conduction, proceeds more uniformly further reducing thermal gradients across the wafer. As can be seen by examination of FIG. 11, the view angle to the heating device along the radial direction varies over one order of magnitude. At a point of about 60 mm from the edge 11 of the substrate 12 (for a 300 mm wafer), the view angle is approximately one-fifth of that near the edge, implying that at least one-fifth of the integrated radiation will be incident at a point 60 mm away from the edge 11 as compared at the wafer's edge 11 .
[0032] Cooling Considerations for Regions I, II and III
[0033] Cooling progresses much in the same way as heating only in reverse. Energy is primarily carried away from central region 18 (Region III) (mainly by conduction) to Regions I and II where it radiates into space from the plurality of flat annular extensions 17 . Since the means exists to transfer energy out from Region III more efficiently than in the ladder boat case, the thermal gradient will be reduced.
[0034] Advantages of this susceptor design are:
[0035] Compatible with current automation designs
[0036] Reduces thermal gradients through better heat energy conduction (wafer center) and screening of radiation (wafer edge)
[0037] Provides almost ideal mechanical support, eliminates gravitational stresses from acting on the substrate
[0038] Can be arranged in a stacked configuration using a modified ladder boat design
[0039] Results in a total mass increase of the thermal load of about double that of the silicon wafer load by itself
[0040] May be possible to use for low-pressure chemical vapor deposition (LPCVD) processing without any dummy wafer requirement to replace absent silicon wafers
[0041] Possible to easily manufacture using low-pressure chemical vapor deposition (LPCVD) SiC technology
[0042] Additional Considerations
[0043] Optimal performance of the susceptor 10 may depend on additional modifications to the basic design. These are illustrated in FIG. 12. The basic design is shown for reference in FIG. 8A. Modification of the main central region 18 by building a concave surface 20 (convex not shown) may be beneficial for certain processing condition and substrate types. Some conditions where this may be needed are processes that will result in some bowing of the wafer 12 due to film stress from the deposition process or from a pre-existing film on the substrate. By incorporating a slightly concave (or convex) surface into the susceptor 10 design, it may permit better physical contact between the substrate and the susceptor support under actual processing conditions.
[0044] Additionally, loading of the substrate may lead to undesired effects if a compressed air layer is allowed to form in the narrow gap between the substrate and the susceptor during the drop off step. If this condition were to occur, the substrate may drift from the desired placement position while floating on a thin blanket of air. Similarly, during the pick up step of the unloading operation, resistance to lifting is possible if good intimate contact exists between the substrate and the susceptor support. In this case, difficulty in lifting the substrate will occur as a partial vacuum will exist between the substrate and the susceptor. To reduce these air pressure effects, it is possible to incorporate a series of small perforations (holes) 24 throughout the central region 18 that will permit air to flow in and out of the region between the substrate 12 and the susceptor 10 with less resistance.
[0045] One particular variation of the claimed invention is the top hat design with the central region 18 of the susceptor 10 removed. That is, a significant central portion of Region III in the wafer support is removed. In this case, some diameter less than the full diameter of the upper wafer support is removed so that the wafer 12 is supported mainly along the outer edge of the wafer support top. Doing so creates an advantageous situation where the mass at the center of such assembly is roughly half of that in a top hat design. This translates to a faster thermal ramping and cooling due to the lower mass amount. Some degree of mechanical support is lost due to the removal of the wafer support at the center, however, depending on the amount of support removed.
[0046] The invention has been described with reference to an exemplary embodiment. This description is for the sake of example only, and the scope and spirit of the invention ought to be construed by appropriate interpretation of the appended claims. | A semiconductor wafer susceptor for batch substrate processing. The susceptor includes a central region in a primary plane and a plurality of flat annular extensions extending below the central region in a secondary plane. The primary and secondary planes are parallel to each other. An edge of the substrate overhangs the central region allowing no contact of the susceptor with the substrate edge. | 8 |
FIELD OF THE INVENTION
[0001] This invention relates to the field of electronic panel filters. In particular, it relates to features which facilitate the manufacture of such a filter and permitted it to operate with higher field potentials.
BACKGROUND TO THE INVENTION
[0002] In the previous art, electronic air filters of the charge media type, a filter medium is positioned between metal screens and polarized by applying high voltage between these screens. In many cases, the high voltage supply is an integral part of the filter. Examples are my U.S. Pat. No. 4,549,887 and U.S. Pat. No. 4,828,586. These inventions effectively describe filters which have two outside grounded screens and an inside screen which is charged with high voltage. Between the screens there are pads of dielectric fibrous trapping material which becomes polarized by the electric field between the screens.
[0003] These filters are usually one or two inches thick and they get their power from a low voltage supply such as 24 volts which is usually available for the air-handling units. These filters use very little power, about 1½ watts to 2 watts. Their electronic system converts a low voltage input to high voltage, eg, approximately 7 KV to 12 KV. The high voltage creates an electrostatic field inside the filter and polarizes the fibrous media which then better attracts the dust from the air flow. The method of attaching the power supply electronics to the filter itself is one object of this invention.
[0004] The amount of voltage which can be applied between these screens is limited by the space between the screens. Typically for a one-inch thick filter, the applied voltage is approximately 7 kilovolts. If the voltage is increased beyond this, avalanche arcing has in the past occurred between the inside screen and the outside grounded screens. This produces a loud sparking noise. Avalanche discharge occurs when a small leakage starts which ionizes the air and generates a conductive path between the screens at one spot. This causes the charge on the inside screen to dissipate abruptly thus making the loud noise. The effect is intense because the inside screen and the outside screens form a capacitor with the dielectric media being the dielectric.
[0005] U.S. Pat. No. 5,573,577, by the same inventor, describes a similar filter where conductive strings are used in place of the inside screen. The purpose of using the strings is to provide internal ionization via the loose ends of the fibers. These strings feature loose fiber ends and they are rendered conductive by some means. In this case, avalanche discharge is very minimal because the strings, by their small total surface have very small capacitance. In practice, they are about 1¼ inches apart. The actual area covered by the strings is much smaller as compared to the area covered by an equivalent screen. This is why the strings have very small capacitance.
[0006] Another object of my invention is therefore to provide a method of allowing a higher voltage to be employed without the presence of severe avalanche discharge.
[0007] By reducing avalanche discharge in these filters and enabling application of higher voltage between the screens, a higher efficiency of the filter is provided.
[0008] The invention in its general form will first be described, and then its implementation in terms of specific embodiments will be detailed with reference to the drawings following hereafter. These embodiments are intended to demonstrate the principle of the invention, and the manner of its implementation. The invention in its broadest and more specific forms will then be further described, and defined, in each of the individual claims which conclude this Specification.
SUMMARY OF THE INVENTION
[0009] The invention herein is based on providing a charged screen in charged media type filters wherein the screen is made of a resistive material, such as a plastic mesh, which is made to have high resistance to current flow. Thus the charged middle screen of a composite filter assembly as described above is made of resistive material and it is charged by high voltage of the order of 7 to 12 KV with respect to the grounded outer screens. The high resistance nature of the middle screen limits large amounts of current from flowing in cases where leakage gives rise to the formation of an arc. By using a highly resistive screen, the area covered by the screen can be the same as with a metal screen but because of the screen's high resistivity, avalanche discharge is reduced eliminated. In this way, we get good polarization, because of the large area covered with little or no avalanche discharge.
[0010] It has been found that if a charged screen has high resistivity then, upon the commencement of the formation of an arc, a small leakage current passing between the charged screen and the outside grounded screens causes the voltage at the point of the arc to decrease. A voltage drop occurs when current flows through the resistance. (V=IR). The presence of resistance prevents a large discharge from being sustained because the voltage across the arc immediately drops.
[0011] Another feature arising from the use of a high resistivity screen is that the resistance prevents the innate capacitance of the rest of the screen from providing high current to flow to the discharge site, consequently, by using resistive charged screens, the applied voltage can be increased thus improving the efficiency of the filter. By using a highly resistive screen, the area covered by the screen is the same as with a metal screen but because of the screen's high resistivity, avalanche discharge is eliminated. In this way, we get good polarization, because of the large area covered with no avalanche discharge.
[0012] According to a further feature of the invention, the electronics box that contains the high voltage power supply is made to interfit with and act as part of the channel formed along one side of the filter. The channel/box combination collectively acts as an extension to the filter and ensures that the filter unit has the shape of a completed rectangle so that, when it is installed in an air handling unit, it will seal properly directing air to pass only through the filter medium.
[0013] The foregoing summarizes the principle features of the invention. The invention may be further understood by the description of the preferred embodiments and drawings which now follow.
BRIEF DESCRIPTION OF THE FIGURES
[0014] FIG. 1 is an exploded perspective view of the air filtration elements of a typical prior art charged media type filter before a resistive screen according to the invention is installed, including a central conductive charged screen.
[0015] FIG. 2 is an exploded perspective view of only an external screen and the central charged screen of FIG. 1 , incorporating a resistive screen according to the invention and depicting a leakage current at the corner of the filter.
[0016] FIG. 3 is a graph positioned above the resistive, central screen, showing the voltage distribution across the resistive screen when leakage current occurs.
[0017] FIG. 4 is a graph showing the improvement in efficiency of a filter using resistive screen as compare to one using metal screen due to the permitted operation of the improved screen at 8.25 kilovolts as opposed to 6.25 kilovolts using the metal screen.
[0018] FIGS. 5 a , 5 b and 5 c , are perspective assembly views the showing respectively the filter in its frame, FIG. 5 a , a channel FIG. 5 b , and the electronics box, FIG. 5 c , positioned to indicate how the high voltage electronics box is assembled by being fitted into the channel, according to prior art procedures to provide an assembled filter module.
[0019] FIGS. 6 a , 6 b , and 6 c are perspective assembly view showing how the high voltage electronic box, FIG. 6 c , according to the invention, is fitted into a shortened channel, FIG. 6 b , present along the side of a filter, shown assembled as FIG. 6 a.
[0020] FIGS. 6 b and 6 c depict the shortened channel and modified electronics box respectively.
[0021] FIG. 6 d is a cross-sectional view taken through the channel member.
[0022] FIG. 6 e is a cross-sectional view taken through the outer casing of the high voltage electronics box.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0023] FIG. 1 shows a typical arrangement and assembly order of the past designs for trapping media and electrical screens in a charged media type electronic air filter. Outside screens 1 and 2 are electrically grounded. A central screen 3 is charged to high voltage from power supply 6 . The high voltage applied between the screens 1 and 2 , and between screens 2 and 3 , generates an electrostatic field which polarizes the dielectric filter trapping media 4 and 5 . The polarization of the trapping media forms positive and negative surface charges on the media fibers, which in turn attract dust.
[0024] In the pre-existing charged media filters, the inside screen is made of metal, which acts as a capacitor between the outside screens 1 and 2 . If by some reason the media 4 and 5 or the surrounding air becomes leaky and a small amount of current flows between the screens 1 , 2 , 3 , this leakage ionizes the surrounding air which then becomes conducting. As a result, the charge on the central screen 3 starts to flow through the initial path. As more and more current flows, this produces further ionization of the air, contributing to more conduction. Finally, a cascade effect develops and the whole charge on the central screen 3 discharges with a spark. This is what is called “avalanche discharge”. It produces an annoying sound, ozone, and momentarily, the electronic features of the air filter ceased to operate.
[0025] As a consequence of this phenomenon, the voltage that can be applied to the central screen of a traditional filter is limited to about 7 kV in the case of a one-inch filter. To eliminate the avalanche effect and be able to apply higher voltage to the central screen 3 , the central screen can be made of a high resistivity material such as plastic. FIG. 2 shows a central screen 3 a which is made of plastic or the like that has high resistivity with a specific resistance of, on the order of, 20 Megohm-centimeters.
[0026] To illustrate the effect of this arrangement, FIG. 2 shows the power supply 6 connected to one end of the high resistivity screen 3 a via conductive, edge-mounted electrode 11 . Electrode 11 continues to distribute high voltage over other portions of the central screen 3 a when a portion of the resistive central screen 3 a is subject to leakage current.
[0027] FIG. 2 also shows a current leakage 8 occurring between the central screen 3 a and the external screen 2 of a filter assembly according to the invention. In this case, the moment some leakage occurs, the voltage on the central screen 3 a around the leakage will drop. Because of the resistance of the central screen 3 a , the leakage will be minimized. No avalanche discharge can occur because the resistance of the central screen 3 a limits the flow of current to the leakage point. When, eventually, leakage current ceases to flow, as when a current-supporting chain of dust particles has been disrupted, the central screen 3 a will re-acquire the full voltage of the power supply 6 across its entire surface.
[0028] FIG. 3 is a graph of the voltage distribution along a diagonal line extending across the central screen 3 a of FIG. 2 between the point where the power supply 6 is connected and the leakage point 8 . If there is no leakage, the voltage profile will be constant, that of the power supply 6 . This is depicted as curve 9 . If a leakage occurs, then the voltage profile will be that of curve 10 . Notice that there is a small voltage drop from the supply voltage even at the point of power supply connection. This is the IR drop in the power supply internal resistance 7 . At the leakage point 8 , the voltage drops much more due to the high resistivity of the central screen 3 a.
[0029] Accordingly, by making the central screen 3 a with a high resistivity material, we can apply higher charging voltage to the assembly of screens which produces higher degree of polarization which, in turn, increases the filter's efficiency. FIG. 4 shows the increased efficiency that arises by boosting the voltage between screens from 6.25 kilovolts to 8.25 kilovolts.
[0030] The graph of FIG. 4 shows results of tests made on otherwise identical filters, one with an inside screen made completely conducting metal mesh and one with a resistive plastic mesh. The metal mesh could accommodate only 6.25 KV before avalanche sparking occurred. The resistive screen could accommodate 8.25 KV. A higher voltage than that would cause excessive discharge but no avalanche sparking occurred. As it can be seen from the test results, the resistive screen has a better overall efficiency due to the higher voltage applied as compared to the filter with the metal screen.
[0031] Turning to the assembly of the electronic high voltage power supply on the filter, FIGS. 5 a , 5 b and 5 c depict the previous art. FIG. 5 a shows a complete filter 12 having a channel 13 extending along one whole side of the filter 12 . Channel 13 is riveted or fastened onto the side frame of filter 12 . An electronic box 14 which contains the high voltage electronics is is located and fastened by fasteners 15 inside the channel 13 as shown in FIG. 5 a . As can be seen, box 14 has to be narrower than the channel 13 in order to fit inside the channel 13 . The channel width is also limited by the width of the filter. Notice also that there is a duplication of walls between the channel and the box around the box area.
[0032] The further improvement of the present invention is shown in FIGS. 6 a , 6 b , 6 c , 6 d and 6 e . In FIG. 6 a , filter 12 has a partial channel 16 mounted along one side, but now covering only part of the filter side. The revised electronics box 17 , which is made, preferably of non-conductive plastic material, has a rear portion 18 which is dimensioned to slidingly fit inside the inner volume 19 of channel 16 . FIG. 6 d shows in cross-sectional view the inner volume 19 of channel 16 . FIG. 6 e shows in cross-sectional view protruding portion 18 extending from box 17 .
[0033] In final assembled format, as shown in FIG. 6 a , channel 16 first is fastened permanently onto the filter 12 . Electronics box 17 is then inserted into the channel by its part 18 engaging within the inner volume 19 , trapped by flanges 16 a . The electronic box is then retained in place by being fastened to the filter only by a single fastener 20 . In this way, electronic box 17 can have the same width as the filter, allowing for more space for electronics. Further, it can be installed or removed by undoing only one fastener 20 . Additionally, there is no duplication of walls around the box area.
CONCLUSION
[0034] The foregoing has constituted a description of specific embodiments showing how the invention may be allied and put in use. These embodiments are only exemplary. The invention in its broadest, and more specific aspects, is further described and define in the claims which now follow.
[0035] These claims, and the language used herein, are to be understood in terms of the variants of the invention, which have been described. They are not to be restricted to such variants, but are to be read as covering the full scope of the invention as is implicit with the invention and the disclosure that has been provided herein. | A polarized media electronic air filter assembly has an electronics box mounted along one side by a slid-in fit into an open, receiving channel. Arcing between screens is reduced by using a relatively resistive material for at least one of the screens exposed to arcing. | 1 |
TECHNICAL FIELD
This application relates to coated abrasive sheet or disc material having loops projecting from its side opposite the abrasive by which the material may be attached to and driven by hooks projecting from a support surface of a pad adapted to be manually or machine driven.
BACKGROUND OF THE INVENTION
Coated abrasive sheet or disc materials are known that can be attached to a pad by releasable engagement of loops on the side of the material opposite the abrasive with hooks projecting from the support surface of the pad. Such an attachment system is much easier and simpler to use than mechanical clamps. Also it provides advantages over the use of pressure sensitive adhesive as an attachment means in that its ability to be attached to a pad is not adversely affected by the presence of loose abrasive or dirt or by environmental conditions such as abnormal moisture, heat or cold so that the abrasive sheet materials with loops can reliably be attached, removed and then reused a number of times.
While these advantages are provided by known coated abrasive sheet material with projecting attachment loops, heretofore it has been expensive to make since the backing layer that provides and anchors the loops has been entirely prepared from yarns intertwined only by weaving or knitting machines that operate at very low speeds.
DISCLOSURE OF THE INVENTION
The present invention provides a novel coated abrasive sheet or disc material with loops projecting from its side opposite the abrasive that comprises a backing layer that provides and anchors the loops including a carrier web which may be formed by much less expensive methods than weaving or knitting, and yarns stitched into the carrier web to form the loops. Such a backing layer can be produced at a high rate of speed compared to weaving or knitting so that the abrasive sheet material according to the present invention is significantly less expensive to make than coated abrasive sheet material with projecting attachment loops prepared by the prior art methods described above.
The carrier web may be of woven or nonwoven construction, with nonwoven carrier webs being preferred because of their generally lower cost. Acceptable nonwoven carrier webs may be formed by conventional techniques such as continuous filament spin bonding or wet laying, with suitable carrier webs of the former type including those sold under the trade designations Typar™ and Reemay™ by DuPont and Cerex™ by Monsanto, and suitable carrier webs of the latter type including those sold under the trade designation Confil™ by International Paper, and Manniweb™ by Manning Paper Co.
The main functions of the carrier web are to provide body and durability for the backing and to be sufficiently tough so that it can be stitched into without ripping or tearing. Preferably the carrier web is also relatively stiff and has a sufficient density to firmly anchor the stitches and provide support for the loops so that they will project outwardly from the surface of the carrier web where they can easily be engaged by the hooks on the pad. Carrier webs having a density generally in the range of 1/2 to 3 ounces per square yard have been found to provide these functions.
The stitches that provide the loops should be made with strong yarn, and preferably of textured, multifilament yard that forms many more potential anchoring loops than a monofilament yarn. 100 Or 150 denier 36 filament textured polyester yarns have been found very suitable for this use.
At present, the only known machine that is capable of placing the stitches in the carrier web at commercially acceptable rates is the Malimo™ type Malipol Stitch-Knitting Machine manufactured by Textima in East Germany and distributed in the United States by Chima, Inc. of Reading, Pa. It is believed, however, that new stitch knitting machines are presently under development that will also provide the needed stitching capability. Such Malipol Stitch-Knitting machines are available that can apply the stitches to carrier webs over 140 inches wide, and can apply up to 1500 stitches per minute while applying about 12 stitches per inch (which is usable for forming abrasive coated material according to the present invention), thereby producing a web speed of about 625 feet per hour which is about 5 to 10 times greater than the web speed produced by known weaving or knitting machines.
The loop height (i.e., the average height that the centers of the loops project above the carrier web) has been varied in the range of 1 to 5 millimeters on the Malipol machine and has been found to produce acceptable engagement of the loops with the hooks on the backing pad throughout that range.
Preferably the loops are formed by making 14 to 18 rows of stitches per inch measured in the cross web direction and making 10 to 40 stitches per inch along the length of the web in each row. It has been found that increasing the stitch density not only increases the number of anchoring sites for the stitches, but also causes the loops that are formed to stand more erect.
Also, the Malipol Stitching Machine can be operated in either a single guide bar mode or in a double guide bar mode. When the double guide bar mode is used, two separate threads are used for each stitch, one to form the loop and the other to lock the stitch more securely in the backing layer. The loops that are formed in the double guide bar mode have been found to stand more erect than loops formed in the single bar guide mode.
To produce abrasive sheet material that will withstand a large number of disengagements from and reengagements with the hooks on a support pad it is necessary to apply an adhesive coating (e.g., thickened or foamed latex, extruded polymer film, or hot melt adhesive) to the side of the carrier web opposite the loops. The adhesive coating will adhere the yarn to itself and to the fibers of the carrier web to restrict the loops from enlarging when they are disengaged from the hooks by tightening the stitches in the backing layer, and will provide additional adhesion between the fibers in the carrier web to restrict tearing of the carrier web when the loops are disengaged from the hooks. Such a coating should not be allowed to pass through to the side of the carrier web from which the loops project, however, or it can reduce the flexibility and erectness of the loops and thereby their ability to engage hooks on the support surface of the pad.
The carrier web with the loops stitched into it may be incorporated into coated abrasive sheet material by using the adhesive coating to bond the side of the carrier web opposite the loops to the side of the backing layer opposite the abrasive granules on conventionally made coated abrasive sheet material. Preferably, however, the abrasive is coated directly onto the adhesive coating over the surface of the carrier web opposite the loops after the adhesive coating has dried so that the adhesive coating prevents the abrasive bonding resin from penetrating the carrier web and affecting the proper presentation of the loops for engagement by hooks on a backing pad.
BRIEF DESCRIPTION OF THE DRAWING
The present invention will be further described with reference to the accompanying drawing wherein like reference numerals refer to like parts in the several views, and wherein:
FIG. 1 is a fragmentary enlarged plan view of the back surface of a first embodiment of sheet material according to the present invention;
FIG. 2 is a sectional view taken approximately along line 2--2 of FIG. 1;
FIG. 3 is a sectional view of a second alternate embodiment of sheet material according to the present invention; and
FIG. 4 is a schematic view of a production line practicing a method according to the present invention for making the coated abrasive sheet material of FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawing there is shown in FIGS. 1 and 2 coated abrasive sheet material generally designated by the reference numeral 10.
The coated abrasive sheet material 10 comprises a nonwoven carrier web 12 having a multiplicity of multifilament threads 13 stitched into it with portions of the threads forming loops 14 projecting from a back surface 15 of the carrier web 12, and a layer of abrasive grains 16 adhered by a bonding resin 18 to a front surface of the carrier web 12 which is sealed by a coating 20 of adhesive. The coating 20 of adhesive both (1) prevents the bonding resin 18 from passing through the carrier web 12 and affecting the loops 14, and (2) locks the threads 13 forming the stitches to themselves and to the fibers of the carrier web 12 to restrict enlarging of the loops 14 by tightening of the stitches in the carrier web 12, and to restrict tearing of the stitched carrier web 12 when the loops 14 on the sheet material 10 are pulled away from hooks on a support pad with which they have been engaged.
The stitches illustrated have been made by the Malipol Stitching Machine described above operated in its single guide bar mode. As can best be seen in FIG. 1, the stitches are made in parallel rows spaced at uniform predetermined distances 22 in a cross direction on the carrier web 12 and having uniform predetermined stitch lengths 24 in the longitudinal direction of the carrier web 12, with the loops 14 being formed in alternating diagonal directions between two of the adjacent rows of stitches to form corresponding zig zag patterns of loops 14 longitudinally along the carrier web 12. Alternatively the stitches could have been made on the same machine using its "double guide bar mode" which provides additional threads to lock the threads forming the loops in the carrier web.
FIG. 3 shows an alternate, less preferred form of coated abrasive sheet material 32 according to the present invention which also comprises a nonwoven carrier web 34 having a multiplicity of multifilament threads 36 stitched into it with portions of the threads forming loops 38 projecting from a back surface 39 of the carrier web 34. A surface of the carrier web 34 opposite its back surface 39 is adhered by a layer of adhesive 40 to a back surface of a backing 42 on a conventional commercially available piece 44 of coated abrasive sheet or disc material (e.g., Tri-M-ite Freecut Paper Open Coat abrasive sheet material available from Minnesota Mining and Manufacturing Company, St. Paul, Minn.) which includes a layer of abrasive grains 48 adhered by a bonding layer 50 on the surface of its backing 42 opposite the carrier web 34. In addition to adhering the carrier web 34 and backing 42 together, the layer of adhesive 40 also locks the threads 36 forming the stitches to themselves and to the fibers of the carrier web 12 to restrict enlarging of the loops 38 by tightening of the stitches in the carrier web 34, and to restrict tearing of the stitched carrier web 34 when the loops on the sheet material 10 are pulled away from the hooks on a support pad with which they have been engaged.
FIG. 4 schematically illustrates a method for forming the coated abrasive sheet material 10 of FIGS. 1 and 2 in which a length of the nonwoven carrier web 12 is fed through a machine 60 (e.g., a Malimo™ type Malipol Stitch-Knitting machine manufactured by Textima in East Germany) supplied with a multiplicity of multifilament threads 62 from a source 64. The machine 60 stitches into the carrier web 12 parallel rows of stitches which are spaced, have stitch lengths along the rows, and produce loops 14 in the pattern shown and described with reference to FIG. 1. The stitched carrier web 12 is then coated on its side opposite the loops 14 by an extender 66 to form the layer of adhesive 20 and provide a backing structure 68. Subsequently, after the backing structure 68 has been dried and slit to a desired width (which steps have not been shown, but which are schematically allowed for by the break lines 70), the backing structure 68 is coated at station 72 with make resin, electrostatically coated with abrasive grains 16 at station 73, and then further coated with size resin to complete the layer of bonding material 18 and dried at station 74 to form the finished coated abrasive material 10.
EXAMPLE
As a specific non-limiting example of the sheet material 10 of FIGS. 1 and 2, a white Confil™ wetlaid nonwoven fabric comprising a blend of cellulose and polyester fibers bonded with a polymer believed to be an acrylate adhesive, purchased as Style 1213033 White Confil wetlaid fabric from International Paper Company, was used as the carrier web 12. That carrier web 12 was stitched on a 14 gauge Malimo™ type Malipol Stitch-knitting Machine operated in its single bar mode with 3 millimeter pile sinkers to produce 14 evenly spaced rows of stitches per inch in a cross web direction and to form 12 stitches per inch along each row, and to form loops 14 projecting from the carrier web by about 1 to 2 millimeters. The thread 13 used to form the stitches was a commercial grade 150 denier, 36 filament textured polyester thread commercially purchased from O'Mara Incorporated, Devon, Pa.
The stitched carrier web was then coated on its surface opposite the loops with a 5 to 8 mil layer of the ethylene/vinyl acetate terpolymer adhesive commercially designated Elvax II 5650T by Dupont applied through a slot die extruder having a die temperature of about 400° F. to form the coating 20 of adhesive.
The adhesive coated stitched carrier web was then dried, slit to a desired width, and electrostatically coated with grade 36 abrasive granules 16 over the coating 20 of adhesive using a phenolic resin size coating and a urea formaldehyde make resin to form the bonding resin 18.
The dried abrasive coated sheet material 10 made in this test exhibited excellent adhesion between the bonding resin 18, the abrasive granules 16 and the coating 20 of adhesive and between the coating 20 of adhesive and the carrier web 12, and no internal delamination of the coated sheet material 10 was noted when discs were cut from it and used to abrade a substrate. | A coated abrasive sheet or disc material having a multiplicity of loops projecting from its side opposite the abrasive, which coated abrasive material is adapted to be held on the support surface of a pad from which project a multiplicity of hooks by releasable engagement between the loops and the hooks while the material is driven by the pad to abrade a workpiece. The backing of the coated abrasive material comprises a carrier web with a multiplicity of multifilament yarns stitched into it with portions of the yarns providing the loops. | 3 |
The present application is a US National Stage of International Application No. PCT/CN2012/084497, filed 13 Nov. 2012, designating the United States, and claiming priority to Chinese Patent Application No. 201110360160.3, filed with the Chinese Patent Office on Nov. 14, 2011 and entitled “Method and apparatus for determining communication parameter and for communication in WLAN”, which is hereby incorporated by reference in its entirety.
FIELD OF THE INVENTION
The present invention relates to the field of Wireless Local Area Network (WLAN) technologies in the field of wireless communication technologies and particularly to a method and apparatus for determining a communication parameter and for communication in a WLAN.
BACKGROUND OF THE INVENTION
At present, WLAN operates in a license-exempt frequency band of 2.4G and has been considered as important means of offloading cellular network services due to its low device cost, easiness to deploy, high data rate and other advantages. A burden on a cellular network can be effectively lowered by using the WLAN to offload webpage browsing, QQ, MSN and other low-value services among the cellular network services or by using the WLAN to offload the cellular network services when congestion occurs in the cellular network, and the WLAN can improve indoor coverage and provide an access at a high speed, to provide subscribers with better wireless network services.
However, after a mobile terminal originally served in the cellular network is handed over to the WLAN, an Access Point (AP) in the WLAN accessed by the mobile terminal may currently be heavily loaded, thus resulting in a poor network quality condition and even a congestion status of the network, and then the mobile terminal communicating in the WLAN through the AP cannot be provided with a high quality of service, so that the mobile terminal may have to be handed over back to the cellular network, thus bringing a higher burden to the cellular network and influencing an experience of the subscriber.
SUMMARY OF THE INVENTION
In view of this, embodiments of the invention provide a method and apparatus for determining a communication parameter and for communication in a WLAN, so as to address the problem in the prior art of a low quality of service while a mobile terminal handed over from a cellular network to the WLAN communicates in the WLAN.
The embodiments of the invention are implemented in the following technical solutions:
An embodiment of the invention provides a method for determining a communication parameter used by a mobile terminal, including:
a base station determining a first communication parameter used by a first mobile terminal in communication in a WLAN, wherein the first mobile terminal is a mobile terminal to be handed over from a cellular network to the WLAN, and the first communication parameter indicates a first wait length of time of the first mobile terminal in the WLAN between determination of an idle channel and communication, and the first wait length of time is shorter than a second wait length of time of a second mobile terminal in the WLAN between determination of an idle channel and communication, and the second mobile terminal is a mobile terminal in the WLAN, which is not handed over from the cellular network to the WLAN; and
sending the determined first communication parameter to the first mobile terminal.
An embodiment of the invention further provides a method for communication by a mobile terminal in a WLAN, including:
a first mobile terminal to be handed over from a cellular network to the WLAN receiving a first communication parameter sent by a base station, wherein the first communication parameter indicates a first wait length of time of the first mobile terminal in the WLAN between determination of an idle channel and communication, and the first wait length of time is shorter than a second wait length of time of a second mobile terminal in the WLAN between determination of an idle channel and communication, and the second mobile terminal is a mobile terminal in the WLAN, which is not handed over from the cellular network to the WLAN; and
communicating in the WLAN using the first communication parameter after accessing the WLAN.
An embodiment of the invention further provides a base station including:
a parameter determination component configured to determine a first communication parameter used by a first mobile terminal in communication in a WLAN, wherein the first mobile terminal is a mobile terminal to be handed over from a cellular network to the WLAN, and the first communication parameter indicates a first wait length of time of the first mobile terminal in the WLAN between determination of an idle channel and communication, and the first wait length of time is shorter than a second wait length of time of a second mobile terminal in the WLAN between determination of an idle channel and communication, and the second mobile terminal is a mobile terminal in the WLAN, which is not handed over from the cellular network to the WLAN; and
a sending component configured to send the determined first communication parameter to the first mobile terminal.
An embodiment of the invention further provides a mobile terminal including:
a reception component configured to receive a first communication parameter sent by a base station, wherein the first communication parameter indicates a first wait length of time of the mobile terminal in a WLAN between determination of an idle channel and communication, and the first wait length of time is shorter than a second wait length of time of a second mobile terminal in the WLAN between determination of an idle channel and communication, and the second mobile terminal is a mobile terminal in the WLAN, which is not handed over from a cellular network to the WLAN; and
a communication component configured to communicate in the WLAN using the first communication parameter after the mobile terminal is handed over from the cellular network to the WLAN.
An embodiment of the invention further provides a method for accessing by a mobile terminal a WLAN, including:
a first mobile terminal to be handed over from a cellular network to a WLAN generating an identity notification message used to notify an AP that the first mobile terminal is a mobile terminal to be handed over from the cellular network to the WLAN; and
sending the identity notification message to the AP in the course of accessing the WLAN through information interaction with the AP.
An embodiment of the invention further provides a method for determining a communication parameter used by a mobile terminal, including:
an AP receiving an identity notification message sent by a first mobile terminal;
determining based upon the received identity notification message that the first mobile terminal is a mobile terminal to be handed over from a cellular network to a WLAN;
determining a first communication parameter used by the first mobile terminal in communication in the WLAN through the AP, wherein the first communication parameter indicates a first wait length of time of the first mobile terminal in the WLAN between determination of an idle channel and communication, and the first wait length of time is shorter than a second wait length of time of a second mobile terminal in the WLAN between determination of an idle channel and communication, and the second mobile terminal is a mobile terminal in the WLAN, which is not handed over from the cellular network to the WLAN; and
sending the determined first communication parameter to the first mobile terminal.
An embodiment of the invention further provides a method for determining a communication parameter used by a mobile terminal, including:
an AP receiving an identity notification message sent by a first mobile terminal;
determining based upon the received identity notification message that the first mobile terminal is a mobile terminal to be handed over from a cellular network to a WLAN;
determining an updated NAV value based upon a currently valid largest one of NAV values configured by other mobile terminals in the WLAN, wherein the updated NAV value is the sum of a remaining length of time and an predicted length of time, and the remaining length of time is a remaining length of time, of a length of time indicated by the largest NAV value, from the current moment, and the predicted length of time is a length of time predicted to be required for the current communication by the first mobile terminal; and
sending an indication message carrying the updated NAV value to the other mobile terminals.
An embodiment of the invention further provides a mobile terminal including:
a message generation component configured to generate an identity notification message used to notify an AP that the mobile terminal is a mobile terminal to be handed over from a cellular network to a WLAN; and
a sending component configured to send the identity notification message to the AP in the course of accessing the WLAN through information interaction with the AP.
An embodiment of the invention further provides an AP, including:
a reception component configured to receive an identity notification message sent by a first mobile terminal;
a terminal determination component configured to determine based upon the received identity notification message that the first mobile terminal is a mobile terminal to be handed over from a cellular network to a WLAN;
a parameter determination component configured to determine a first communication parameter used by the first mobile terminal in communication in the WLAN through the AP, wherein the first communication parameter indicates a first wait length of time of the first mobile terminal in the WLAN between determination of an idle channel and communication, and the first wait length of time is shorter than a second wait length of time of a second mobile terminal in the WLAN between determination of an idle channel and communication, and the second mobile terminal is a mobile terminal in the WLAN, which is not handed over from the cellular network to the WLAN; and
a sending component configured to send the determined first communication parameter to the first mobile terminal.
An embodiment of the invention further provides an AP, including:
a reception component configured to receive an identity notification message sent by a first mobile terminal;
a terminal determination component configured to determine based upon the received identity notification message that the first mobile terminal is a mobile terminal to be handed over from a cellular network to a WLAN;
an NAV determination component configured to determine an updated NAV value based upon a currently valid largest one of NAV values configured by other mobile terminals in the WLAN, wherein the updated NAV value is the sum of a remaining length of time and an predicted length of time, and the remaining length of time is a remaining length of time, of a length of time indicated by the largest NAV value, from the current moment, and the predicted length of time is a length of time predicted to be required for the current communication by the first mobile terminal; and
a sending component configured to send an indication message carrying the updated NAV value to the other mobile terminals.
Advantageous effects of the invention are as follows.
In a method according to an embodiment of the invention, for a first mobile terminal to be handed over from a cellular network to a WLAN, a base station determines a first communication parameter used by the first mobile terminal in communication in the WLAN and sends the determined first communication parameter to the first mobile terminal. Correspondingly, the first mobile terminal receives the first communication parameter sent by the base station and then communicates in the WLAN using the first communication parameter after accessing the WLAN. Since a first wait length of time, used by the first mobile terminal in the WLAN, indicated by the first communication parameter is shorter than a second wait length of time used by the second mobile terminal in the WLAN, which is not handed over from the cellular network to the WLAN, the first mobile terminal can occupy an idle channel for communication at a priority higher than the second mobile terminal, to improve a quality of service while the mobile terminal handed over from the cellular network to the WLAN communicates in the WLAN.
In a method according to an embodiment of the invention, a first mobile terminal to be handed over from a cellular network to a WLAN sends an identity notification message to an AP in the course of accessing the WLAN through information interaction with the AP, to notify the AP that the first mobile terminal is a mobile terminal to be handed over from the cellular network to the WLAN. Correspondingly, the AP determines based upon the received identity notification message that the first mobile terminal is a mobile terminal to be handed over from the cellular network to the WLAN and then determines an updated Network Allocation Vector (NAV) value based upon a currently valid largest one of NAV values configured by other mobile terminals in the WLAN and sends an indication message carrying the updated NAV value to the other mobile terminals, so that the other mobile terminals will not try to occupy a channel in the WLAN for a length of time indicated by the updated NAV value, and thus the first mobile terminal can occupy an idle channel for communication at a priority for a predicted length of time in the length of time indicated by the updated NAV value, to improve the quality of service while the mobile terminal handed over from the cellular network to the WLAN communicates in the WLAN.
Other features and advantages of the invention will be set forth in the following description, and partially become apparent from the description or be learned upon practice of the invention. The objects and other advantages of the invention can be attained and achieved by structures particularly pointed out in the written description, the claims and the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a flow chart of communication by a mobile terminal in a WLAN in the prior art;
FIG. 2 is a schematic diagram of communication by a mobile terminal in a WLAN in the prior art;
FIG. 3 is a first flow chart of a method for determining a communication parameter used by a mobile terminal according to an embodiment of the invention;
FIG. 4 is a first flow chart of a method for communication by a mobile terminal in a WLAN according to an embodiment of the invention;
FIG. 5 is a flow chart of a mobile terminal being handed over from a cellular network to a WLAN and communicating according to a first embodiment of the invention;
FIG. 6 is a flow chart of a method for accessing by a mobile terminal a WLAN according to an embodiment of the invention;
FIG. 7 is a second flow chart of a method for determining a communication parameter used by a mobile terminal according to an embodiment of the invention;
FIG. 8 is a flow chart of a mobile terminal being handed over from a cellular network to a WLAN and communicating according to a second embodiment of the invention;
FIG. 9 is a third flow chart of a method for determining a communication parameter used by a mobile terminal according to an embodiment of the invention;
FIG. 10 is a flow chart of a mobile terminal being handed over from a cellular network to a WLAN and communicating according to a third embodiment of the invention;
FIG. 11 is a schematic structural diagram of a base station according to a fourth embodiment of the invention;
FIG. 12 is a schematic structural diagram of a mobile terminal according to a fifth embodiment of the invention;
FIG. 13 is a schematic structural diagram of a mobile terminal according to a sixth embodiment of the invention;
FIG. 14 is a schematic structural diagram of an access point according to a seventh embodiment of the invention; and
FIG. 15 is a schematic structural diagram of an access point according to an eighth embodiment of the invention.
DETAILED DESCRIPTION OF THE EMBODIMENTS
In order to provide solutions to improve a quality of service while a mobile terminal handed over from a cellular network to a WLAN communicates in the WLAN, embodiments of the invention provide a method and apparatus for determining a communication parameter and for communication in a WLAN, and preferred embodiments of the invention will be described below with reference to the drawings. It shall be appreciated that the preferred embodiments described here are merely intended to illustrate and explain the invention but not to limit the invention. The embodiments of the invention and features in the embodiments can be combined with each other unless there is confliction.
In order to facilitate understanding of the solutions according to the embodiments of the invention, in the following description, firstly a flow for a mobile terminal to communicate in a Carrier Sense Multiple Access network with Collision Avoidance (CSMA/CA) scheme in a WLAN in the prior art is described, and as illustrated in FIG. 1 , the flow includes the following steps:
Step 101 . A mobile terminal A determines whether a channel is idle through carrier sense before transmitting data to a target mobile terminal B.
Step 102 . The mobile terminal A starts to communicate by firstly sending a Request to Send (RTS) message to the mobile terminal B after a wait length of time elapses after determining that the channel is idle, as illustrated in FIG. 2 .
The wait length of time includes a Distributed Inter Frame Space (DIPS) and a random wait length of time, and since the random wait length of time is generated randomly in a preset random algorithm, generally a different random wait length of time is used by a different mobile terminal, to alleviate confliction of a channel occupied by different mobile terminals in communication.
Step 103 . The mobile terminal B returns a Clear To Send (CTS) message to the mobile terminal A after a length of time indicated by a Short Inter Frame Space (SIFS) elapses after receiving the RTS message sent by the mobile terminal A.
Step 104 . The mobile terminal A transmits data to the mobile terminal B after the length of time indicated by the SIFS elapses after receiving the CTS message returned by the mobile terminal B.
Step 105 . The mobile terminal B returns an Acknowledgement (ACK) to the mobile terminal A after the length of time indicated by the SIFS after receiving the data which needs to be sent by the mobile terminal A.
So far the current data communication between the mobile terminal A and the mobile terminal B ends and the channel is changed from the occupied status to the idle status.
In the data communication process as illustrated in FIG. 1 , the mobile terminal A carries a Network Allocation Vector (NAV) value, configured by the mobile terminal A, in the RTS message to indicate that the channel will be occupied in a next length of time indicated by the NAV value, and the mobile terminal B carries an NAV value, configured by the mobile terminal B, in the CTS message to indicate that the channel will be occupied in a next length of time indicated by the NAV value. As illustrated in FIG. 2 , the RTS message and the CTS message may also be received by other mobile terminals in the WLAN, which thus can determine from the NAV values carried therein the length of time in which the channel will be occupied and will not try to occupy the channel for data transmission.
An embodiment of the invention provides a method for determining a communication parameter used by a mobile terminal, and as illustrated in FIG. 3 , the method includes the following steps:
Step S 301 . A base station determines a first communication parameter used by a first mobile terminal in communication in a WLAN, where the first mobile terminal is a mobile terminal to be handed over from a cellular network to the WLAN, and the first communication parameter indicates a first wait length of time of the first mobile terminal in the WLAN between determination of an idle channel and communication, and the first wait length of time is shorter than a second wait length of time of a second mobile terminal in the WLAN between determination of an idle channel and communication, and the second mobile terminal is a mobile terminal in the WLAN, which is not handed over from the cellular network to the WLAN.
Step S 302 . The base station sends the determined first communication parameter to the first mobile terminal.
Correspondingly, an embodiment of the invention further provides a method for communication by a mobile terminal in a WLAN, and as illustrated in FIG. 4 , the method includes the following steps:
Step S 401 . A first mobile terminal to be handed over from a cellular network to a WLAN receives a first communication parameter sent by a base station.
Step S 402 . The first mobile terminal communicates in the WLAN using the first communication parameter after accessing the WLAN.
The method according to the embodiment of the invention will be described below in detail by way of a first embodiment with reference to the drawings.
First Embodiment
FIG. 5 is a flow chart of a mobile terminal being handed over from a cellular network to a WLAN and communicating according to the first embodiment of the invention, which includes the following steps.
Step S 501 . A mobile terminal initiates a service in a cellular network, and a base station serving the mobile terminal determines to hand over the mobile terminal to a WLAN, which provides the mobile terminal with the service initiated by the mobile terminal. The base station may determine to hand over the mobile terminal to the WLAN based upon the type of the service initiated by the mobile terminal, for example, the base station may hand over the mobile terminal, which initiates some specified type of service, to the WLAN; or the base station may determine to hand over the mobile terminal to the WLAN based upon a network quality condition of the base station, for example, the base station may determine to hand over the mobile terminal to the WLAN when the base station currently is heavily loaded.
In order for a convenient description and to facilitate distinguishing, hereinafter a mobile terminal to be handed over from a cellular network to a WLAN is referred to as a first mobile terminal, and a mobile terminal in the WLAN, which is not handed over from the cellular network to the WLAN, is referred to as a second mobile terminal, for example, a mobile terminal accessing the WLAN directly.
Step S 502 . The base station interacts with an AP in the WLAN for information and may particularly interact with a specified AP near to the first mobile terminal for information.
A second communication parameter determined by the specified AP in the WLAN and used by a second mobile terminal in communication in the WLAN through the specified AP can be obtained through information interaction with the specified AP, where the second communication parameter indicates a second wait length of time of the second mobile terminal in the WLAN between determination of an idle channel and communication, and the second wait length of time may include a DIFS and/or a random wait length of time, so the second communication parameter includes a parameter for determination of the DIFS used by the second mobile terminal and/or a parameter for determination of the random wait length of time used by the second mobile terminal.
The current network quality condition of the specified AP in the WLAN, e.g., a load condition, an average delay of a data packet, a congestion condition, etc., can be further obtained through information interaction with the specified AP.
Step S 503 . The base station determines a first communication parameter used by the first mobile terminal in communication in the WLAN, where the first communication parameter indicates a first wait length of time of the first mobile terminal in the WLAN between determination of an idle channel and communication, and the first wait length of time may include a DIFS and/or a random wait length of time, so the first communication parameter includes a parameter for determination of the DIFS used by the first mobile terminal and/or a parameter for determination of the random wait length of time used by the first mobile terminal.
In this step, the first communication parameter may be determined particularly in the following schemes:
In a first scheme, the base station does not need to communication with the specified AP in the step S 502 before determining the first communication parameter, and particularly the following two scenarios may be involved:
In a first scenario, when the second wait length of time used by the second mobile terminal in the WLAN is kept unchanged after being preset, for example, the DIFS is a fixed value, the random wait length of time is determined in a fixed random algorithm, and the range of values of the random wait length of time is also fixed, then the base station can know the second wait length of time in advance and thus can determine the first communication parameter based upon the second wait length of time, where the first wait length of time indicated by the first communication parameter is shorter than the second wait length of time, for example, the first communication parameter includes the value of the DIFS in the first wait length of time, and/or a parameter for determining a random wait length of time, where the range of values of the random wait length of time determined by using the parameter is shorter than the range of values of the random wait length of time in the second wait length of time. Since the second wait length of time in this step is kept unchanged after being preset, the first communication parameter can be determined in this scheme without requiring the base station to communicate with the specified AP in the step S 502 .
In a second scenario, the second wait length of time used by the second mobile terminal in the WLAN is determined by the AP according to the network condition or the type of the service initiated by the terminal, and the second mobile terminal is notified of the determined parameter indicating the second wait length of time, and in this case the base station can know the second wait length of time in advance and thus can determine the first communication parameter based upon the second wait length of time, where the first wait length of time indicated by the first communication parameter is shorter than the second wait length of time, and the first communication parameter may be a parameter for determining the first wait length of time based upon the second wait length of time, for example, the first communication parameter is the difference of the second wait length of time minus the first wait length of time, so that the first mobile terminal can know the difference from the base station and determine the first wait length of time for use based upon the second wait length of time known from the specified AP.
In a second scheme, the second wait length of time used by the second mobile terminal in the WLAN is determined by the AP according to the network condition or the type of the service initiated by the terminal, and the second mobile terminal is notified of the determined parameter indicating the second wait length of time, and in this case the base station determines the second wait length of time indicated by the second communication parameter based upon the second communication parameter obtained from the specified AP in the step S 502 and then determines the first communication parameter based upon the second wait length of time, and reference can be made to the first scenario in the first scheme for details thereof, so a repeated description thereof will be omitted here.
In a third scheme, the base station determines the first communication parameter used by the first mobile terminal based upon the current network quality condition of the specified AP obtained in the step S 502 , where the poorer the current network quality condition is, the shorter the first wait length of time indicated by the determined first communication parameter is; and
In the third scheme, preferably, the first mobile terminal is disabled from accessing the WLAN through the specified AP when the current network quality condition of the specified AP obtained in the step S 502 is poorer than a preset network quality condition.
In a fourth scheme, the base station determines a quality requirement for the service currently requested by the first mobile terminal and determines the first communication parameter used by the first mobile terminal based upon the determined quality requirement, where the higher the quality requirement is, the shorter the first wait length of time indicated by the first communication parameter is.
Preferably, in this first embodiment, the first communication parameter may be determined in any combination of the four determination schemes described above, and a repeated description thereof will be omitted here.
Step S 504 . The base station sends the determined first communication parameter to the first mobile terminal after determining the first communication parameter and may particularly send the first communication parameter, corresponding to the specified AP in the WLAN, to the first mobile terminal.
Step S 505 . The first mobile terminal is handed over from the cellular network to the WLAN after receiving the first communication parameter sent by the base station and may particularly access the WLAN through the specified AP, and a particular access scheme may be any of numerous schemes in the prior art, so a repeated description thereof will be omitted here.
Step S 506 . The first mobile terminal communicates in the WLAN using the first communication parameter after accessing the WLAN, that is, the first mobile terminal communicates in the WLAN using the first wait length of time indicated by the first communication parameter. Reference can be made to the flows illustrated in FIG. 1 and FIG. 2 above for use of the first wait length of time in communication in the WLAN, so a repeated description thereof will be omitted here.
Particularly communication can be performed in the WLAN using the first communication parameter through the specified AP subsequent to an access to the WLAN through the specified AP.
With the solution according to the first embodiment described above, since the first wait length of time, used by the first mobile terminal in the WLAN, indicated by the first communication parameter is shorter than the second wait length of time used by the second mobile terminal in the WLAN, the first mobile terminal can occupy the idle channel for communication at a priority higher than the second mobile terminal, to improve the quality of service while the mobile terminal handed over from the cellular network to the WLAN communicates in the WLAN.
As can be apparent from the foregoing description of the solution illustrated in FIG. 5 , when the first wait length of time includes the DIFS and the random wait length of time, the random wait length of time is determined in the random algorithm, and the range of values of the random wait length of time determined by using the parameter, in the first communication parameter, for determining the random wait length of time is shorter than the range of values of the random wait length of time in the second wait length of time, but there may still some probability that the random wait length of time in the first wait length of time is not shorter than the random wait length of time in the second wait length of time in determination of the random wait length of times, so that the first wait length of time may not shorter than the second wait length of time. However, generally, since the DIFS in the first wait length of time is shorter than the DIFS in the second wait length of time, and the range of values of the random wait length of time in the first wait length of time is shorter than the range of values of the random wait length of time in the second wait length of time, so there is a higher probability that the first wait length of time is shorter than the second wait length of time, and thus it will still be possible to improve the quality of service while the mobile terminal handed over from the cellular network to the WLAN communicates in the WLAN.
Moreover, it is impossible that the first wait length of time is not shorter than the second wait length of time when the first communication parameter is the difference of the second wait length of time minus the first wait length of time.
An embodiment of the invention further provides a method for accessing by a mobile terminal a WLAN, and as illustrated in FIG. 6 , the method includes the following steps:
Step S 601 . A first mobile terminal to be handed over from a cellular network to a WLAN generates an identity notification message.
Step S 602 . The first mobile terminal sends the identity notification message to an AP in the course of accessing the WLAN through information interaction with the AP, where the identity notification message is used to notify the AP that the first mobile terminal is a mobile terminal to be handed over from the cellular network to the WLAN.
Correspondingly, an embodiment of the invention further provides a method for determining a communication parameter used by a mobile terminal, and as illustrated in FIG. 7 , the method includes the following steps:
Step S 701 . An AP receives an identity notification message sent by a first mobile terminal.
Step S 702 . The AP determines based upon the received identity notification message that the first mobile terminal is a mobile terminal to be handed over from a cellular network to a WLAN.
Step S 703 . The AP determines an updated NAV value based upon a currently valid largest one of NAV values configured by other mobile terminals in the WLAN, where the updated NAV value is the sum of a remaining length of time and a predicted length of time, and the remaining length of time is a remaining length of time, of the largest NAV value, from the current moment, and the predicted length of time is a length of time predicted to be required for the current communication by the first mobile terminal.
Step S 704 . The AP sends an indication message carrying the updated NAV value to the other mobile terminals.
The method according to the embodiment of the invention will be described below in detail by way of a second embodiment with reference to the drawings.
Second Embodiment
FIG. 8 is a flow chart of a mobile terminal being handed over from a cellular network to a WLAN and communicating according to the second embodiment of the invention, which includes the following steps:
Step S 801 . A first mobile terminal to be handed over from a cellular network to a WLAN generates an identity notification message carrying information indicating that the first mobile terminal is a mobile terminal to be handed over from the cellular network to the WLAN.
For example, 1-bit information may be added into an existing Probe Request frame sent by a mobile terminal when accessing an AP, or 1-bit information may be added into an Association Request frame, and the Probe Request frame or the Association Request frame with the 1-bit information added may be used as the identity notification message, where the added 1-bit information is the information indicating that the first mobile terminal is a mobile terminal to be handed over from the cellular network to the WLAN.
Step S 802 . The first mobile terminal sends the identity notification message to an AP in the course of accessing the WLAN through information interaction with the AP, where the identity notification message is used to notify the AP that the first mobile terminal is a mobile terminal to be handed over from the cellular network to the WLAN.
Step S 803 . After receiving the identity notification message sent by the first mobile terminal, the AP determines based upon the received identity notification message that the first mobile terminal is a mobile terminal to be handed over from the cellular network to the WLAN.
Step S 804 . The AP determines an updated NAV value based upon a currently valid largest one of NAV values configured by other mobile terminals in the WLAN, where the updated NAV value is the sum of a remaining length of time and a predicted length of time, and the remaining length of time is a remaining length of time, of a length of time indicated by the largest NAV value, from the current moment, and the predicted length of time is a length of time predicted to be required for the current communication by the first mobile terminal.
This step may be performed particularly as follows:
The AP receives RTS messages and CTS messages sent by the other mobile terminals and obtains carried NAV values from the RTS messages and the CTS messages, where the obtained NAV values are NAV values configured by the other mobile terminals; and after obtaining an NAV value, the AP maintains a validity status of the NAV value based upon a moment when the NAV value is received and a length of time indicated by the NAV value, where the NAV value is valid for the length of time indicated by the NAV value from the moment when the NAV value is received, and the NAV value is invalid after the length of time indicated by the NAV value from the moment when the NAV value is received; and the AP determines a currently valid largest NAV value by maintaining the validity statuses of the NAV values configured by the other mobile terminals;
With reference to the current moment, the AP determines a remaining length of time, of the length of time indicated by the largest NAV value, from the current moment, that is, the length of time indicated by the NAV value minus a length of time from the moment when the NAV value is received to the current moment;
The AP predicts a length of time required for the current communication by the first mobile terminal, which is referred to as the predicted length of time, possibly particularly as follows: the AP determines the predicted length of time corresponding to the type of the current service, reported by the first mobile terminal, based upon the type of the service; or determines the predicted length of time based upon the amount of data to be transmitted of the current service, reported by the first mobile terminal; or determines the predicted length of time is a preset default predicted length of time, where the first mobile terminal may report the type of the current service or the amount of data to be transmitted of the current service to the AP in the course of accessing the WLAN; and the default predicted length of time may be determined according to a real network condition and real characteristics of current various types of services;
The AP determines the updated NAV value is the sum of the remaining length of time and the predicted length of time.
Step S 805 . The AP sends an indication message carrying the updated NAV value to the other mobile terminals.
The indication message may be sent to the other mobile terminals based upon a scheme to transmit an RTS message and a CTS message in the prior art, and the format of the indication message may be the same as the format of the RTS message or the CTS message, and the update NAV value may be carried in a field, for carrying an NAV value, in the RTS message and the CTS message, so that the indication message can be received and recognized by the other mobile terminals without any modification to the other mobile terminals. In this case, since the indication message can also be received by the first mobile terminal, in order to avoid the first mobile terminal from communication using the updated NAV value carried in the indication message upon reception of the indication message, invalid flag information, for example, identification information of the first mobile terminal, may be carried in the indication message, so that the first mobile terminal may determine that the updated NAV value carried in the indication message is invalid thereto after recognizing the invalid flag information corresponding thereto from the indication message.
Step S 806 . After receiving the indication message, the other mobile terminals obtain the carried updated NAV value therefrom and control their communication processes in the WLAN based upon the length of time indicated by the updated NAV value, and reference can be made to the flows illustrated in FIG. 1 and FIG. 2 above for the function of the NAV value, so a repeated description thereof will be omitted here.
With the solution according to the second embodiment of the invention, the other mobile terminals will not try to occupy a channel in the WLAN for the length of time indicated by the updated NAV value, so that the first mobile terminal can occupy an idle channel for communication at a priority for the predicted length of time in the length of time indicated by the updated NAV value, to improve the quality of service while the mobile terminal handed over from the cellular network to the WLAN communicates in the WLAN.
Based upon the method for accessing by a mobile terminal a WLAN as illustrated in FIG. 6 above, correspondingly, an embodiment of the invention further provides a method for determining a communication parameter used by a mobile terminal, and as illustrated in FIG. 9 , the method includes the following steps:
Step S 901 . An AP receives an identity notification message sent by a first mobile terminal.
Step S 902 . The AP determines based upon the received identity notification message that the first mobile terminal is a mobile terminal to be handed over from a cellular network to a WLAN.
Step S 903 . The AP determines a first communication parameter used by the first mobile terminal in communication in the WLAN through the AP, where the first communication parameter indicates a first wait length of time of the first mobile terminal in the WLAN between determination of an idle channel and communication, and the first wait length of time is shorter than a second wait length of time of a second mobile terminal in the WLAN between determination of an idle channel and communication, and the second mobile terminal is a mobile terminal in the WLAN, which is not handed over from the cellular network to the WLAN.
Step S 904 . The AP sends the determined first communication parameter to the first mobile terminal.
The method according to the embodiment of the invention will be described below in detail by way of a third embodiment with reference to the drawings.
Third Embodiment
FIG. 10 is a flow chart of a mobile terminal being handed over from a cellular network to a WLAN and communicating according to the third embodiment of the invention, which includes the following steps:
Step S 1001 . A first mobile terminal to be handed over from a cellular network to a WLAN generates an identity notification message carrying information indicating that the first mobile terminal is a mobile terminal to be handed over from the cellular network to the WLAN.
For example, 1-bit information may be added into an existing Probe Request frame sent by a mobile terminal accessing an AP, or 1-bit information may be added into an Association Request frame, and the Probe Request frame or the Association Request frame with the 1-bit information added may be used as the identity notification message, where the added 1-bit information is the information indicating that the first mobile terminal is a mobile terminal to be handed over from the cellular network to the WLAN.
Step S 1002 . The first mobile terminal sends the identity notification message to an AP in the course of accessing the WLAN through information interaction with the AP, where the identity notification message is used to notify the AP that the first mobile terminal is a mobile terminal to be handed over from the cellular network to the WLAN.
Step S 1003 . After receiving the identity notification message sent by the first mobile terminal, the AP determines based upon the received identity notification message that the first mobile terminal is a mobile terminal to be handed over from the cellular network to the WLAN.
Step S 1004 . The AP determines a first communication parameter used by the first mobile terminal in communication in the WLAN through the AP, where the first communication parameter indicates a first wait length of time of the first mobile terminal in the WLAN between determination of an idle channel and communication, and the first wait length of time is shorter than a second wait length of time of a second mobile terminal in the WLAN between determination of an idle channel and communication, and the second mobile terminal is a mobile terminal in the WLAN, which is not handed over from the cellular network to the WLAN.
In this step, the first communication parameter may be determined in a scheme in the step S 503 in FIG. 5 above, except that it is determined by the base station in the step S 503 and determined by the AP in this step, so a repeated description of a particular process will be omitted here.
Step S 1005 . The AP sends the determined first communication parameter to the first mobile terminal after determining the first communication parameter.
Step S 1006 . The first mobile terminal communicates in the WLAN using the first communication parameter sent by the AP, that is, the first mobile terminal communicates in the WLAN using the first wait length of time indicated by the first communication parameter, after receiving the first communication parameter. Reference can be made to the flows illustrated in FIG. 1 and FIG. 2 above for use of the first wait length of time in the course of communication in the WLAN, so a repeated description thereof will be omitted here.
With the solution according to the third embodiment described above, since the first wait length of time, used by the first mobile terminal in the WLAN, indicated by the first communication parameter is shorter than the second wait length of time used by the second mobile terminal in the WLAN, the first mobile terminal can occupy an idle channel for communication at a priority higher than the second mobile terminal, to improve the quality of service while the mobile terminal handed over from the cellular network to the WLAN communicates in the WLAN.
Fourth Embodiment
Based upon the same inventive idea, following the method for determining a communication parameter used by a mobile terminal according to the embodiment of the invention above, correspondingly, the fourth embodiment of the invention further provides a base station, and FIG. 11 illustrates a schematic structural diagram of the base station including:
a parameter determination component 1101 configured to determine a first communication parameter used by a first mobile terminal in communication in a WLAN, where the first mobile terminal is a mobile terminal to be handed over from a cellular network to the WLAN, and the first communication parameter indicates a first wait length of time of the first mobile terminal in the WLAN between determination of an idle channel and communication, and the first wait length of time is shorter than a second wait length of time of a second mobile terminal in the WLAN between determination of an idle channel and communication, and the second mobile terminal is a mobile terminal in the WLAN, which is not handed over from the cellular network to the WLAN; and
a sending component 1102 configured to send the determined first communication parameter to the first mobile terminal.
Preferably, the base station further includes:
an interaction and obtainment component 1103 configured to obtain a second communication parameter, determined by a specified AP in the WLAN, used by the second mobile terminal in communication in the WLAN through the specified AP, through information interaction with the specified AP, before the parameter determination component 1101 determines the first communication parameter used by the first mobile terminal in communication in the WLAN, where the second communication parameter indicates the second wait length of time; and
the parameter determination component 1101 is further configured to determine the first communication parameter used by the first mobile terminal in communication in the WLAN through the specified AP based upon the second wait length of time indicated by the second communication parameter.
Preferably, the base station further includes:
an interaction and obtainment component 1103 configured to obtain the current network quality condition of the specified AP in the WLAN through information interaction with the specified AP before the parameter determination component 1101 determines the first communication parameter used by the first mobile terminal in communication in the WLAN; and
the parameter determination component 1101 is further configured to determine the first communication parameter used by the first mobile terminal in communication in the WLAN through the specified AP based upon the obtained current network quality condition of the specified AP, where the poorer the current network quality condition is, the shorter the first wait length of time is.
Preferably, the base station further includes:
a quality requirement determination component 1104 configured to determine a quality requirement of a service currently requested by the first mobile terminal before the parameter determination component determines the first communication parameter used by the first mobile terminal in communication in the WLAN; and
the parameter determination component 1101 is further configured to determine the first communication parameter used by the first mobile terminal in communication in the WLAN based upon the determined quality requirement, where the higher the quality requirement is, the shorter the first wait length of time is.
Fifth Embodiment
Based upon the same inventive idea, following the method for communication by a mobile terminal in a WLAN according to the embodiment of the invention above, correspondingly, the fifth embodiment of the invention further provides a mobile terminal which is a mobile terminal to be handed over from a cellular network to a WLAN, and FIG. 12 illustrates a schematic structural diagram of the mobile terminal including:
a reception component 1201 configured to receive a first communication parameter sent by a base station, where the first communication parameter indicates a first wait length of time of the mobile terminal in the WLAN between determination of an idle channel and communication, and the first wait length of time is shorter than a second wait length of time of a second mobile terminal in the WLAN between determination of an idle channel and communication, and the second mobile terminal is a mobile terminal in the WLAN, which is not handed over from the cellular network to the WLAN; and
a communication component 1202 configured to communicate in the WLAN using the first communication parameter after accessing the WLAN.
Sixth Embodiment
Based upon the same inventive idea, following the method for accessing by a mobile terminal a WLAN according to the embodiment of the invention above, correspondingly, the sixth embodiment of the invention further provides a mobile terminal which is a mobile terminal to be handed over from a cellular network to a WLAN, and FIG. 13 illustrates a schematic structural diagram of the mobile terminal including:
a message generation component 1301 configured to generate an identity notification message carrying information used to notify an AP that the mobile terminal is a mobile terminal to be handed over from a cellular network to a WLAN; and
a sending component 1302 configured to send the identity notification message to the AP in the course of accessing the WLAN through information interaction with the AP.
Preferably, the mobile terminal further includes:
a reception component 1303 configured to receive a first communication parameter sent by the AP, where the first communication parameter indicates a first wait length of time of the mobile terminal in the WLAN between determination of an idle channel and communication, and the first wait length of time is shorter than a second wait length of time of a second mobile terminal in the WLAN between determination of an idle channel and communication, and the second mobile terminal is a mobile terminal in the WLAN, which is not handed over from the cellular network to the WLAN; and
a communication component 1304 configured to communicate in the WLAN using the first communication parameter after accessing the WLAN.
Seventh Embodiment
Based upon the same inventive, following the method for determining a communication parameter used by a mobile terminal according to the embodiment of the invention above, correspondingly, the seventh embodiment of the invention further provides an AP, and FIG. 14 illustrates a schematic structural diagram of the AP including:
a reception component 1401 configured to receive an identity notification message sent by a first mobile terminal;
a terminal determination component 1402 configured to determine based upon the received identity notification message that the first mobile terminal is a mobile terminal to be handed over from a cellular network to a WLAN;
a parameter determination component 1403 configured to determine a first communication parameter used by the first mobile terminal in communication in the WLAN through the AP, where the first communication parameter indicates a first wait length of time of the first mobile terminal in the WLAN between determination of an idle channel and communication, and the first wait length of time is shorter than a second wait length of time of a second mobile terminal in the WLAN between determination of an idle channel and communication, and the second mobile terminal is a mobile terminal in the WLAN, which is not handed over from the cellular network to the WLAN; and
a sending component 1404 configured to send the determined first communication parameter to the first mobile terminal.
Eighth Embodiment
Based upon the same inventive idea, following the method for determining a communication parameter used by a mobile terminal according to the embodiment above, correspondingly, the eighth embodiment of the invention further provides an AP, and FIG. 15 illustrates a schematic structural diagram of the AP including:
a reception component 1501 configured to receive an identity notification message sent by a first mobile terminal;
a terminal determination component 1502 configured to determine based upon the received identity notification message that the first mobile terminal is a mobile terminal to be handed over from a cellular network to a WLAN;
an NAV determination component 1503 configured to determine an updated NAV value based upon a currently valid largest one of NAV values configured by other mobile terminals in the WLAN, where the updated NAV value is the sum of a remaining length of time and a predicted length of time, and the remaining length of time is a remaining length of time, of a length of time indicated by the largest NAV value, from the current moment, and the predicted length of time is a length of time predicted to be required for the current communication by the first mobile terminal; and
a sending component 1504 configured to send an indication message carrying the updated NAV value to the other mobile terminals.
Preferably, the NAV determination component 1503 is further configured to determine the predicted length of time as follows:
to determine the predicted length of time corresponding to the type of the current service, reported by the first mobile terminal, based upon the type of the service; or
to determine the predicted length of time based upon the amount of data to be transmitted of the current service, reported by the first mobile terminal; or
to determine the predicted length of time is a preset default predicted length of time.
In summary, in the solution according to the embodiments of the invention, a base station determines a first communication parameter used by a first mobile terminal in communication in a WLAN, where the first mobile terminal is a mobile terminal to be handed over from a cellular network to the WLAN, and the first communication parameter indicates a first wait length of time of the first mobile terminal in the WLAN between determination of an idle channel and communication, and the first wait length of time is shorter than a second wait length of time of a second mobile terminal in the WLAN between determination of an idle channel and communication, and the second mobile terminal is a mobile terminal in the WLAN which is not handed over from the cellular network to the WLAN; and the base station sends the determined first communication parameter to the first mobile terminal. Correspondingly, the first mobile terminal to be handed over from the cellular network to the WLAN receives the first communication parameter sent by the base station and communicates in the WLAN using the first communication parameter after accessing the WLAN. With the solutions according to the embodiments of the invention, a quality of service while the mobile terminal handed over from the cellular network to the WLAN communicates in the WLAN is improved.
Those skilled in the art shall appreciate that the embodiments of the invention can be embodied as a method, a system or a computer program product. Therefore the invention can be embodied in the form of an all-hardware embodiment, an all-software embodiment or an embodiment of software and hardware in combination. Furthermore the invention can be embodied in the form of a computer program product embodied in one or more computer useable storage mediums (including but not limited to a disk memory, a CD-ROM, an optical memory, etc.) in which computer useable program codes are contained.
The invention has been described in a flow chart and/or a block diagram of the method, the device (system) and the computer program product according to the embodiments of the invention. It shall be appreciated that respective flows and/or blocks in the flow chart and/or the block diagram and combinations of the flows and/or the blocks in the flow chart and/or the block diagram can be embodied in computer program instructions. These computer program instructions can be loaded onto a general-purpose computer, a specific-purpose computer, an embedded processor or a processor of another programmable data processing device to produce a machine so that the instructions executed on the computer or the processor of the other programmable data processing device create means for performing the functions specified in the flow(s) of the flow chart and/or the block(s) of the block diagram.
These computer program instructions can also be stored into a computer readable memory capable of directing the computer or the other programmable data processing device to operate in a specific manner so that the instructions stored in the computer readable memory create an article of manufacture including instruction means which perform the functions specified in the flow(s) of the flow chart and/or the block(s) of the block diagram.
These computer program instructions can also be loaded onto the computer or the other programmable data processing device so that a series of operational steps are performed on the computer or the other programmable data processing device to create a computer implemented process so that the instructions executed on the computer or the other programmable data processing device provide steps for performing the functions specified in the flow(s) of the flow chart and/or the block(s) of the block diagram.
Although the preferred embodiments of the invention have been described, those skilled in the art benefiting from the underlying inventive concept can make additional modifications and variations to these embodiments. Therefore the appended claims are intended to be construed as encompassing the preferred embodiments and all the modifications and variations coming into the scope of the invention.
Evidently, those skilled in the art can make various modifications and variations to the invention without departing from the spirit and scope of the invention. Thus the invention is also intended to encompass these modifications and variations thereto so long as the modifications and variations come into the scope of the claims appended to the invention and their equivalents. | A communication parameter determination method, and a WLAN communication method and device, comprising: a base station determines a first communication parameter used by a first mobile terminal for communication in a WLAN, the first communication parameter representing a first waiting time of the first mobile terminal in the WLAN from the time of determining that the channel is idle to the time of starting to communicate, and the first waiting time being less than a second waiting time of a second mobile terminal in the WLAN from the time of determining that the channel is idle to the time of starting to communicate; the base station transmits the determined first communication parameter to the first mobile terminal. Accordingly, the first mobile terminal about to switch from a cellular network to the WLAN receives the first communication parameter transmitted by the base station; and after accessing the WLAN, the first mobile terminal uses the first communication parameter to communicate in the WLAN. The solution provided in an embodiment of the present invention improves the WLAN communication quality for a mobile terminal that has switched from a cellular network to a WLAN. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the invention
This invention relates to a microwave integrated circuit mixer (MIC mixer) using a strip line or a microstrip line, etc. for outputting an IF signal with a frequency equal to the difference between the frequencies of the input radio frequency signal and a local oscillation signal (LO signal).
2. Description of a Prior Art
FIG. 1 shows a typical example of a prior art MIC mixer configuration. In the FIG. 1 circuit, a radio frequency signal (hereinafter RF signal) fed through an RF input terminal 1 propagates on a main line 2 and is supplied to a mixer diode 3, i.e., a frequency mixing element. A local oscillation signal (hereinafter LO signal) generated in a microwave oscillator 4 is given to the mixer diode 3 after passing through a band-pass filter (BPF) 5 for the LO signal which is coupled to the main line 2 at the respective high frequencies and passes only the LO signal selectively. Then the output of the mixer diode 3 is supplied to an IF signal output terminal 7 through a low-pass filter 6 which passes only the IF signal, and an end A of the mixer diode 3 is short-circuited for the RF signal and for the LO signal by a high frequency short-circuiting technique where a 1/4 wavelength transmission line is used. In the conventional apparatus of FIG. 1, the input terminal 1 is connected to the main line 2 through an IF interruption circuit 8 which has a passing characteristic for the input RF signal, but works as an open circuit impedance for the IF signal and is provided on the main line 2 at a distance of 1/4 wavelength of the IF signal (≃1/4λ if ) from the mixer diode 3. Accordingly, the input side terminal "B" of the mixer diode 3 becomes short-circuited to a ground in the IF signal frequency. In the microwave oscillator 4, a high frequency use FET 21 is provided in a manner that drain terminal 22 thereof is connected to a strip line 23 which has 1/4 wavelength of the oscillation frequency, and the strip line 23 is open ended. The gate terminal 24 of the FET 21 is connected to one end of a strip line 25, and the other end of the strip line 25 is ground through a dummy resistor 26. A dielectric resonator 27 is disposed so as to be coupled with the strip line 25. The source terminal 28 of FET 21 is connected to one end of a strip line 29, the other end of which is grounded through a dummy resistor 19, so that the output of the oscillator which oscillates at a resonance frequency of the dielectric resonator 27 is taken out from the strip line 29 and fed to the mixer diode 3 through a filter circuit 29+5 and the main line 2. A low-pass filter 30 for feeding a bias current consists of a high impedance line part and a low impedance line part. The low impedance line part of the low-pass filter 30 is connected through a resistor 31 to a capacitor 32, and a bias power source is fed through a connection point between the resistor 31 and the capacitor 32. As the IF interruption circuit 8, a band-pass filter which has a small insertion loss for RF signals and a wide pass-band, and in actual practice may be an inter-digital type direct-current block where two open-ended strip lines are parallel-coupled over a length nearly equal to 1/4 wavelength (λs/4) of the RF signal from the open end as shown in FIG. 2, can be used. The capacitance due to a gap between the two open-ended strip-lines parallel-coupled is, for example, several 0.01 pF when the frequency of a RF signal is 12 GHz, and accordingly, the impedance of the gap capacitance becomes several kΩ when the IF frequency is 1 GHz, and the impedance can be ragarded as almost an open-circuit impedance. However, if a resonance circuit having a resonance characteristic in a frequency range of the IF signal is constituted in a circuit to be connected to the RF input terminal 1, then the gap capacitance of the IF interruption circuit 8 will work as a coupling capacitance, and accordingly, an impedance seen from the terminal "B" of the mixer diode 3 towards the IF interruption circuit 8 begin to have resonance characteristics, and the terminal "B" of the mixer diode 3 is not short-circuited to a ground around the resonance frequency.
Accordingly, the output impedance for the IF frequency at the output terminal 7 is greatly influenced around the resonance frequency, and the condition of the output matching at the IF signal is greatly influenced. As a summary, the frequency spectral characteristic of the mixer circuit begins to display a steep defect phenomenon, which is a fatal defect of the mixer circuit.
Furthermore, in a microwave oscillator 4, the gain of the transistor increases generally as the frequency becomes lower, and accordingly, a spurious oscillation is likely to be produced. In generally, in FIG. 1, provided that a reflection coefficient seen from the gate 24 of FET 21 towards FET 21 is S 11 and a reflection coefficient seen from the gate terminal 24 towards the dummy resistor 26 is Γ R , then the oscillation is carried out when the following condition is fulfilled:
S.sub.11 ×Γ.sub.R =1 (1).
Accordingly, when the resonance circuit is set in a manner that the reflection coefficient Γ R is |Γ R |≃1 only for the frequency around the resonance frequency of the dielectric resonator 27, and |Γ R |≃0 for the frequency other than the resonance frequency, then the microwave oscillator 4 of FIG. 1 stably oscillates at a resonance frequency of the dielectric resonator 27. Hereupon, though the resistor 26 is constituted to have the reflection coefficient |Γ|≃0 in a frequency band of the used frequency, it is not always so for the frequency lower than or higher than the resonance frequency. For instance, when a dummy resistor comprising a 50Ω resistor and a 1/4 wavelength opened-ended strip line are used, the above-mentioned dummy resistor shows a characteristic of |Γ|≃0 for the frequency range of lower than 1 GHz or 7-14 GHz when the LO frequency is 11 GHz, but is shows a characteristic of |Γ|≃1 for the frequency range of 2-6 GHz. On the other hand, the FET 21 has a tendency to increase its gain as the frequency becomes lower, accordingly the reflection coefficient |S' 11 | for a small signal seen from the gate terminal 24 towards FET 21 begins to display a negative characteristic to a low frequency, and accordingly |S 11 '|>1. Accordingly, even for the frequency range of |Γ|≃1 except for the LO frequency, the oscillation condition of S 11 ×Γ R =1 can be satisfied, and this becomes the cause of a spurious oscillation, which is likely to be induced in a frequency range of 3-5 GHz.
SUMMARY OF THE INVENTION
A purpose of the present invention is to provide a mixer circuit wherein fatal defects of frequency characteristics in the IF range are prevented by providing meons which prevent the IF interruption circuit from working as a coupling capacitance, and a spurious oscillation at a frequency lower than the LO signal frequency is prevented by minimizing the reflection coefficient |S 11 '| seen from the gate terminal or base terminal of an oscillation transistor towards the oscillation transistor thereby to eliminate or minimize negative resistance in the LO circuit, thereby a desired normal LO signal is given to a mixer diode. Further, in the present invention, by connecting a resistor-ended low-pass filter to a main line at a point which is on a side of the RF input terminal with respect to and IF interruption circuit and of a high impedance for intermediate frequency, the occurrence of resonance of an impedance seen from the IF interruption circuit towards the RF signal input terminal within the IF range will be prevented. In a microwave oscillator of a mixer circuit, by using a strip line having a length equal to 1/4 wavelength of a spurious oscillation frequency and having one end open and having the other end connected to one end of a resistor which is connected by its other end to a low-pass filter for a bias feeding circuit constituted by a high impedance line and a low impedance line, an impedance seen from a bias connection terminal of an oscillation transistor towards the low-pass filter is adjusted to have a matching condition fulfilled, thereby to eliminate or drastically decrease negative resistance in the local oscillator to prevent spurious oscillation.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is the pattern diagram of the conventional example of a prior art mixer circuit.
FIG. 2 is the pattern diagram of a 1/4 wavelength line coupling type inter-digital direct current block according to the prior art.
FIG. 3 is a pattern diagram of a first example embodying the present invention.
FIG. 4 is a frequency spectral diagram of a reflection coefficient |Γd| of an impedance seen from the drain terminal of an FET of a microwave oscillator part towards a drain bias circuit side in FIG. 3.
FIG. 5 is a pattern diagram of another example embodying the present invention.
FIG. 6 is a pattern diagram of another example embodying the present invention.
FIG. 7 is a pattern diagram of another example embodying the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Hereinafter, the present invention will be made more apparent from the following detailed description taken in conjunction with the drawings FIG. 3 to FIG. 7, wherein the same numerals are put on the same parts and components as those shown in FIG. 1 and FIG. 2.
The mixer circuit comprises a local oscillator 4', a band-pass filter 5 for passing only a LO signal, a strip line 29 ended with a dummy resistor 19 and coupled to the band-pass filter 5 to feed the LO signal thereto, a main line 2 coupled to the band-pass filter 5 to receive the LO signal, an IF interruption circuit 8 connected between the RF input terminal 1 and the input side of the main line 2, a mixer diode 3 connected at an output side of the main line 2 and a low-pass filter 6 connected between the output terminal of the mixer diode 3 and an output terminal 7. The low-pass filter 6 is for passing only IF signal to the output terminal 7 and short-circuits the output end A of the mixer diode 3 to a ground in the RF frequency and the LO frequency. The IF output is issued at and taken out from the output terminal 7. The IF interruption circuit 8 is a capacitor which passes input RF signal from the input terminal 1, but works as open impedance against IF signal and is disposed at a point of 1/4 wavelength of the IF signal (≃1/4λ if ) from the output end B on the main line 2. One end of another low-pass filter 10 is connected at a point which is between the RF input terminal 1 and the IF interruption circuit 8 and is a high impedance point for the IF signal. And the other end of the low-pass filter 10 is ended with an ending circuit 11 which comprises a resistor 15 and a bypass capacitance 16.
In the microwave local oscillator 4', an oscillation transistor such as FET 21 is connected by its drain terminal to one end of a strip line 23 of about 1/4 wavelength of the oscillation frequency with its other end open ended, by its source terminal to the strip line 29, and by its gate terminal to one end of a strip line 25 which is terminated at its other end with a dummy resistor 6. The strip line 25 is coupled with a dielectric resonator 27. The other end of the strip line 29 is ended with a dummy resistor 19. A low-pass filter 30 for connection to a bias source circuit and consisting of a high impedance line part and a low impedance line part is connected to the strip line 23 with its high impedance line part, and the other end of the low-pass filter 30 is connected through a resistor 31 to the bias feeding source. A strip line 33 having about 1/4 wavelength of a spurious oscillation frequency with one end open-ended is connected at the other end to the junction point J of the resistor 31 at the bias source circuit. A capacitor 32 for direct current blocking and high frequency bypassing is connected to the junction point J.
An input side point C of the main line 2 is of a high impedance for IF signals, and a low-pass filter 10 ended with a resistor 15 and a capacitor 16 is connected to the point C. Accordingly, even when a resonance circuit is formed at the point of the RF signal input terminal 1, such a resonance circuit is damped by the resistor of the ending circuit 11. Therefore, the impedance seen from the input side end B of the mixer diode toward the IF interruption circuit 8 does not have undesirable resonance characteristic in impedance, and the input end B is certainly short-circuited to a ground for IF signals, thereby the fatal defect of prior art mixer circuits can be prevented.
In the microwave local oscillator 4', the reflection coefficient |Γd| seen from the drain terminal 22 towards the low-pass filter 30 becomes small for the spurious oscillation frequency. This is because, by means of the open-ended strip line 33 being about 1/4 of the wavelength of the spurious oscillation frequency, the junction point J is short-circuited to a ground in the spurious oscillation frequency regardless of the state of impedance seen from the junction point J toward the ground point 34, and therefore the resistor 31 works as a damping resistor. Accordingly, a reflection coefficient S 11 ' seen from the gate terminal 24 of the FET 21 towards the FET 21 decreases or loses characteristics of negative resistance for the spurious oscillation signal, and thereby, the spurious oscillation is prvented.
FIG. 4 shows a spectral characteristic of the reflection coefficient |Γd| seen from the drain terminal 22 of the FET 21 towards the low-pass filter 30 of the embodiment of the present invention in solid curve in comparison with the conventional example shown by broken curve. By selecting the resistance of the resistor 31 and the length of the strip line 33 appropriately, the spurious oscillation can be prevented. For instance, by constituting an oscillator of the oscillation frequency of 11 GHz as shown in FIG. 1, a spurious oscillation was produced at about 4 GHz, but by adopting the constitution of FIG. 3, and selecting the resistance of the resistor 31 to be several Ω to 60 Ω the spurious oscillation of the about 4 GHz was eliminated.
In the example of FIG. 3, only by adding the strip line 33 in the total oscillator 4', can the spurious oscillation be effectively eliminated. For a change of the spurious oscillation frequency, the line length of the strip line 33 can be easily changed, and therefore the present invention is effective against spurious oscillation for a wide range of frequencies. Furthermore, since the resistance of the resistor 31 can be changed in a wide range from several Ω to about 60Ω, the value of the resistor can be selected corresponding to the voltage of the bias source, and this is another great advantage.
FIG. 5 is another example embodying the present invention wherein the local oscillator 4' is substantially the same as that of FIG. 3, but another low-pass filter 12 of open end type is connected to the main line 2 at a point close to the IF interruption circuit 8 on the side of the mixer diode 3 with respect to the IF interruption circuit 8, and a length from the open end of the low-pass filter 12 to the end B of the main line 2, connected to the mixer diode 3, is selected to be 1/4 wavelength of the IF signal (≃1/4λ if ). Other parts are substantially the same as the circuit of FIG. 3.
In this example of FIG. 5, since the low-pass filter 10 is connected to the main line 2 at the high impedance point C for the IF signal, even when an undesirable resonance circuit is coupled to the RF input terminal 1, such a resonance circuit is damped by the ending circuit 11 containing the resistor 15. Furthermore, by providing the open ended low-pass filter 12, the transmission loss of the main line 2 for the RF signal can be reduced to a minimum value even under a condition that the frequency of the IF signal is low, without making the line length of the main line 2 longer, but only making the line length of the low-pass filter 12 longer.
FIG. 6 is still another embodiment of the present invention. The local oscillator 4' is substantially the same as that of FIG. 3, and a FET 13 comprising an amplifier is connected by its gate G to the RF signal input terminal 1, by its drain D to an end of the main line 2 and by its source S to ground. Other parts and components are constituted in the same manner as those of the circuit of FIG. 3, but the drain bias of the FET 13 is supplied from a terminal 17 which is connected between a capacitor 16 and a resistor 15 of an ending circuit 11.
In the example of FIG. 6, the resistor ended low-pass filter 10 is connected to the main line at the latter's point C of high impedance for the IF signal, and accordingly, even when an undesirable resonance circuit is formed in the side of the FET amplifier 4, the resonance circuit is damped by the resistance 15 of the ending circuit 11. As a result, the impedance seen from the input side end B of the mixer diode 3 toward the IF interruption circuit 8 will have no resonance characteristics, and the point B is certainly short-circuited to ground for the IF signal, and the fatal defect produced in the prior art mixer circuit can be prevented. Furthermore, since the low-pass filter 10, the resistor 15 and the bypass capacitor 16 also form the drain bias circuit for the FET amplifier 14, there is no need of providing an individual bias circuit for the FET amplifier 14, apart from the resonance prevention circuit for the mixer circuit, and therefore the circuit can be made small and concise. And furthermore, since the resistor ended low-pass filter 10 is connected to the main line 2 at the high impedance point C, it is effective to prevent undesirable spurious oscillation which is liable to occur in the bias circuit 11.
FIG. 7 shows a still another embodiment, wherein the microwave local oscillator 4" is modified. In this example, a penetration type capacitor 35 is employed in place of the ordinary capacitor 32 of FIG. 3, and other parts and components are substantially the same as those of FIG. 3. Accordingly, the technical advantage and merits in preventing spurious oscillation by the strip line 33 and the resistor 31 are the same as that of FIG. 3. However, in this example, as a result of the employment of the penetration type capacitor 35 in a direct current locking and a high frequency bypass use, possible variations of local oscillation frequency induced by a spatial shift of the lead wire connecting the junction point J and the bias source can be prevented.
In every one of the above-mentioned embodiments, the oscillation element is not necessarily limited to the FET but a bipolar transistor may be used, and in such case the drain in the above-mentioned elucidation should be changed to the collector and the gate to the base and the source to the emitter, respectively. As has been elucidated in detail, according to the present invention, a steep defect in spectral characteristics in the intermediate frequency range of the mixer circuit can be prevented, and a microwave mixer circuit with splended characteristics is obtainable. Besides, in its microwave oscillator, undesirable spurious oscillations can be prevented for a wide frequency range only by adding an open-ended strip line of 1/4 wavelength of a spurious oscillation frequency. Furthermore, as the damping resistor to prevent the spurious oscillation, a resistor of a wide range such as from several Ω to about 60Ω can be used, thereby enabling a wide range selection of drain or collector bias resistors for various values of voltage of the bias voltage source. | A mixer circuit in which resonance characteristics of a resonance circuit coupled to the RF input terminal are prevented from entering the mixer circuit, and in which negative resistance characteristics in the local oscillator circuit are prevented from causing spurious oscillations in the mixer circuit. The mixer circuit comprises a main strip line connecting an RF input terminal to an output terminal through a frequency mixing diode and a low pass filter. The IF signal is short circuited where the mixer diode is connected to the main strip line, by a high frequency short-circuiting technique. An IF interrupt circuit is provided in the main strip line near the RF input. A resistor ended low pass filter is connected between the RF terminal and the IF interruption circuit. The local oscillator includes a strip line having a length equal to one quarter of the wavelength of the spurious oscillation which is to be prevented. | 7 |
This application is a continuation of Ser. No. 06/031,166 filed Mar. 26, 1987 now abandoned which is a continuation of 06/851,319 filed Apr. 9, 1986 now abandoned which is a continuation of application Ser. No. 755,541 filed July 15, 1985, now abandoned, which is a continuation of application Ser. No. 585,025 filed Mar. 5, 1984, now abandoned, which is a continuation of application Ser. No. 330,065 filed Dec. 15, 1981, now abandoned.
BACKGROUND OF THE INVENTION
A. Field of the Invention
This invention relates to the field of art of level indicator control systems using capacitive probes for indication and control of a substance in a tank.
B. Background Art
It is well known that the level of a substance, i.e. a fluid or granular solid, in an open or closed tank or vessel can be measured and controlled by many, fundamentally similar, methods. Measurement and control is usually based on the concept that the change in fluid level in the tank is equivalent to displacing the top surface of the fluid.
In an earlier method of measurement and control, floats were used to detect and regulate the fluid level in a container. The method employs direct-actuated types of liquid level detectors and is applicable to open tanks or vessels which are subject to atmospheric pressure. However, when using closed tanks, water level is detected in a system under pressure. An arrangement used for this purpose includes one valve positioned at the lowest fluid level point in the tank. Periodic opening of these valves will establish the presence of either steam or water at each valve permitting an inference to be drawn concerning the actual water level in the tank.
Later detectors measured the fluid level in a tank by sensing the hydrostatic head of the fluid and converting this pressure measurement to actual fluid level height or fluid volume. For open tanks, a pressure-gauge-type instrument may be used. A connection is made to the pressure gauge at the minimum or zero fluid level. The full scale range of the gauge is made equal to the head of the fluid in the tank. There are numerous variations of this method including adaptations to tanks where the pressure gauge cannot be located at the zero level and where the medium to be measured is a solid.
A pressure gauge is not practical for measuring fluid level in a pressurized tank, since the actual level to be measured represents only a very small equivalent percentage of the static pressure of the fluid in the tank. Also, an added difficulty is that unless the tank pressure is held constant, the pressure gauge reading is of no value since the change in pressure alters the initial zero level reading. To overcome these problems, differential pressure measuring devices were used to measure the fluid level in pressurized tanks. Connections are made at both high and low fluid levels, one to each side of the differential pressure device, i.e. a Bellows-type meter. The separate connection to each side of the differential pressure device provides for a balancing of the effect of static pressure since it exerts the same force on both the high-pressure and low-pressure side of the tank. Therefore, the pressure head which actuates the detector is the difference between the constant reference and variable fluid level in the tank.
Other devices, improvements and adaptations of float-operated level sensors were developed based on the principles previously discussed. For example, a float may be connected to an electrical switch for providing an alarm, operating a solenoid valve or indicating when a discrete amount of fluid has been poured in or removed from the tank. Floats may be used to operate control valves directly to prevent further fluid flow to the tank, and displacement-type float units may be used to operate control units and remote transmitters.
Another method for detecting fluid levels in tanks utilizes the concept that certain fluids will conduct electricity, while air in a relative sense does not, so that the fluid level may be established through the physical contact of the probe and the conductive fluid. Since the change in fluid level is equivalent to displacing the top surface of the fluid, the usually linear displacement may be measured by resistive, capacitive, magnetic, or photoelectric transducers. Further methods of level detection include temperature-sensing transducers, multi-turn potentiometers operated by a float actuated cable and ultrasonic and gamma-ray adsorption.
A computer-based control system uses well known signal acquisition input instrumentation to obtain analog signals from sensors and transducers, such as capacitance probes, in the tank and transmits them to the computer. To close the fluid level control loop, D/A converters and digital output channels may be used to transmit the signals used to drive on-off fluid level controllers and actuators. Devices such as relays or stepper motors for opening and closing pneumatic fluid valves are also provided control signals from the computer along digital output channels for controlling the fluid flow into and out of the tank. The processor may, for example, compare the input signals from the fluid level transducers with upper and lower set point limits in order to control, in on-off, proportional, integral or differential modes, the fluid flow to the tank to maintain the desired liquid level within a predetermined range. Alarm monitoring and faulty transducer detection can also be performed by the computer.
Analog controllers may be used without a computer processor for controlling the level of fluid in a tank. The analog controller may either use its own set point reference voltage to control fluid input to the tank or it may accept fluid level set point limits from a central processor for the same purpose.
Output devices such as strip chart recorders using properly scaled paper, calibrated meters with d'Arsonval movement and digital displays have all been used to show the amount and the height of fluid in tanks.
SUMMARY OF THE INVENTION
An on-line level indicator control system is used for automatically calibrating high and low set point levels of substances such as fluids or solids in shaped containers. A transmitter produces a present level signal that is proportional to the capacitance between a probe positioned within a container and the container. Logic means produces a time interval signal that is a function of the duration of the present level signal and represents the present level of the substance in the container. Calibration switches provide the memory with calibrated set points representing the percent of fullness of the container at predetermined low and high fluid or solid levels as a function of the time interval signal. An extrapolator receives the high and low set points and the present level signal for providing an indication of the present level within a calibrated range of fluid or solid levels for the container as measured from the bottom to the top of the container. A fail-safe mode controls the filling or draining of the container when a short or open is detected.
Therefore, it is an object of this invention to provide on-line substantially automatic calibration of high and low fluid level set points as a function of probe capacitance each corresponding to a percentage of the tank that contains fluid at any two identified high and low levels substantially within the range from the bottom to the top of the tank.
It is another object of this invention to use the arbitrarily selected high and low fluid level set points to produce a scale that includes substantially all of the possible levels of fluid that could be in the tank in terms of percent of tank filled as the actual fluid height is monitored through the operation of the level indicator control system.
It is a further object of this invention to provide, simultaneously, the actual level and amount(volume) of fluid in the tank during the course of operation of the level indicator control system.
It is an additional object of this invention to avoid recalibration of the high/low set point levels during level control operation using the same tank.
It is another object of this invention to eliminate adjustments to the probe transmitter while in operation in the field.
Still another object of this invention is to provide a fail-safe mode when the line between the probe transmitter and the control system opens or shorts.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a circuit diagram of the on-line level indicator control system of the invention;
FIG. 2 shows the output waveform of the multivibrator illustrated in FIG. 1.
FIG. 3 shows the output pulses of the crystal coupled oscillator illustrated in FIG. 1.
FIG. 4 shows the output signals of the AND gate illustrated in FIG. 1.
FIGS. 5A-B illustrates a flow chart of the computer program that detects when the system shown in FIG. 1 is in a fail-safe mode.
DESCRIPTION OF THE PREFERRED EMBODIMENT
As shown in FIG. 1 level indicator control system 10 includes capacitance probe 12, transmitter 15, crystal coupled oscillator 16, AND gate 34, counter 18, a control system comprising microprocessor 20, manual data input and set point calibration switches 44 and flow control circuit 22.
Probe 12 is positioned within a shaped container such as tank 24. The probe, which may be substantially in the shape of a cylinder or plate, forms a capacitor with tank wall 26. As the substance 28, i.e., fluid or granular solid, fills tank 24, the capacitance between probe 12 and wall 26 changes since the varying amount of substance alters the dielectric properties of the space between one capacitor element, the probe, and the second capacitor element, the tank wall. Over time, the amount of substance that is initially in the tank will not remain constant and, therefore, the capacitance between the probe and the wall, the probe capacitance, will vary as the level of substance in the tank varies. Probe 12 produces an input signal along line 30 to transmitter 15 which is a function of the change in probe capacitance. Probe capacitance is a function of the amount of probe submerged by the substance or the distance between a plate type probe and the surface of the substance below it. Transmitter 15 includes multivibrator 14 which changes its output frequency as a function of the change in probe capacitance provided along line 30. The transmitter may be mounted in the head of the probe.
Referring now to FIG. 2, the signal transmitted from probe 12 to multivibrator 14 controls the width of multivibrator output signal 54 along line 36. Specifically, the width of waveform 50 of signal 54 is a function of the probe capacitance. As the capacitance increases the output of multivibrator 14 produces waveform 52 which is wider than waveform 50 as shown in FIG. 2. Output signal 54 of multivibrator 14 is applied to logical AND gate 34 along line 36. Crystal coupled oscillator 16 provides a continuous series of pulses 56 as shown in FIG. 3 to AND gate 34 along line 39. The output of AND gate 34 is provided along line 38 to counter 18 where only those oscillator pulses, 57a, 57b, that occurred within the width of waveform 50 and 52 respectively, are counted to provide a time interval signal representing each of the widths of the waveforms of multivibrator output signal 54. The number of oscillator pulses, 57a, 57b, counted within the width of each multivibrator output waveform 50 and 52, as shown in FIG. 4, is a function of the probe capacitance that substantially produced each waveform. This capacitance of probe 12 is a function of the change in dielectric properties of the substance 28 between probe and tank wall which is also a function of the amount of substance in the tank or the level of the substance in the tank. The oscillator, AND gate and counter form a logic means for providing a time interval signal to memory 42 in microprocessor 20.
In this embodiment, the time interval signal, which is a function of the duration or width of each output waveform of the multivibrator, is calibrated to represent the percentage of the tank that contains fluid. Specifically, an output signal waveform has a time interval, τ 1 , that is proportional to the probe capacitance and represents, for this example, that 35% of the tank is filled with the fluid or granular solid. Another, longer waveform time interval, τ 2 , may indicate that the tank is 45% filled. Furthermore, since each time interval signal represents the percentage of the tank that contains fluid and since the contents of the tank will be filling and emptying due to the conditions imposed on its use, it becomes important to know, in certain situations, how high the fluid level is at any given moment in terms of the percentage of the tank that contains fluid as well as whether the fluid has exceeded a particular level or not. To accomplish this task, two known time interval signals are provided, one that represents the point at which the tank is substantially filled with fluid, a high set point limit, and one that represents the point at which the tank is substantially empty of fluid, a low set point limit. A scale of percentages about these two limits is produced where the scale is calibrated to represent the percent fullness of the tank at any given time about the limits set by the two high and low set points. Each scale has elements that represent the fullness of the container as measured from the bottom of the container to a point on the container identified by a scale element. The method and device for measuring the unknown level of fluid in a tank, for controlling the amount of fluid in the tank and for providing a scale that is calibrated in terms of percent of tank filled and where each value of the scale is a function of the probe capacitance is as follows.
Probe 12 may be installed in an angular position suitable for the size and shape of any tank. Probes installed from the side of the tank should be angled downward to allow the fluid or granular solid to drain or slide off the probe. An adjustable time delay may be included to eliminate spurious operation of system 10 due to splashing or agitation of the fluid in the tank. In FIG. 1, probe 12 is positioned vertically in cylindrically shaped tank 24. Changing the level condition of substance 28 of tank 24 will change the capacitance between the probe and the tank wall. Since this capacitance is transmitted to multivibrator 14 by way of a signal along line 30 and since the frequency with which the multivibrator jumps between positive and negative voltage states is controlled by the capacitance signal transmitted to it, the shape of output signal 54 from multivibrator 14 will vary as a function of the probe capacitance.
Crystal coupled oscillator 16 provides clock pulses along line 39 to gate 34. The multivibrator output signal waveforms are also provided as input to gate 34 along line 36. Gate 34 produces, by logical conjunction of the clock pulses with the multivibrator output waveforms, gated output signals along line 38 which are provided to counter 18. Counter 18 produces signals that substantially represent the width of each of the waveforms produced by the multivibrator. The digital signals produced by the counter are provided to a predetermined location in microprocessor memory 42 along line 40. The counter output may represent a desired low or high fluid or substance level set point signal, representing the percentage of the tank that contains fluid at substantially that moment, which is to remain in memory indefinitely. Manual data input and set point calibration switches 44 are provided for the purpose of entering relative input parameters and storing the low and high fluid or substance level signals in memory 42 of microprocessor 20. The calibration switches provide for fluid level signals to be stored in memory that represent the operation measurement of substantially any liquid level in the tank in terms of percent of fullness of the tank on a scale of from 0% to 100%. Non-linear conversion of the level signals to units of volume or flow rate in open channel flow systems may be obtained through suitable, well-known microprocessor based linearizing means regardless of the shape of the tank. The low fluid or substance level set point signal may not necessarily represent the fluid level in the tank when it is completely empty and the high fluid level signal may not necessarily represent the fluid or substance level in the tank when it is completely full. The set points are automatically calibrated in terms of the percent of fluid in tank 28. The high and low set points in memory 42 are provided to extrapolator 46 along data lines 48a. Extrapolator 46 uses both the high level set point, which may represent the tank fluid level other than at 100% full, and low level set point, which may represent the tank fluid level at a point other than when the tank is empty. Extrapolator 46 will then establish the proper range of percentages of fullness of the tank in the range between empty (0%) and full (100%) after operating on the two low and high set points obtained from memory 42. In this example of a fluid tank with a high set point other than 100% and a low set point other than 0%, control means 20 accomplishes extrapolation to produce the percent fullness in the range between 0% and the low set point, in the range between the high set point and 100%, as well as the range between the set points.
Extrapolator 46 in microprocessor 20 not only produces a scale having the range of fluid levels in the tank in terms of the percentage of fullness of the tank but may also use the instantaneous digital signals provided by the counter 18 as stored in the memory 42 and the counter values and the corresponding manually entered percentages for the respective high and low set points to provide the volume of fluid in the tank at virtually any moment during its use. The method of determining the present substance level, Z, is given by the equation (1).
Z=X+[(Y-X)*((C-A)/CB-A))] (1)
Where the "*" indicates the multiplication operator and the values represented by the variables A,B,C,X and Y are given in the following table.
TABLE______________________________________ Time Substance Levels Interval Signals (in terms of percent of fullness)______________________________________Low Set Point A XHigh Set Point B YPresent Level C Z______________________________________
Fluid flow rate may also be determined in open channel systems. Extrapolator 46 may, by way of a table look-up feature, determine fluid levels in oddly shaped containers and compensate for non-linearities of probe configurations due to tanks of different geometries.
System 10 provides a level control mode of operation by comparing in logic and controller section 48 the actual fluid level or volume in the tank with either the higher or lower set point values provided to the section along line 51 from memory 42. For example, if overfilling of a tank is to be avoided and the actual fluid level exceeds the high limit set point in memory 42, then a signal is provided from controller 48 along line 50 to proportional control valve 22, which may also include a stepper motor or a similarly functioning device, to stop the flow of fluid through line 29 into tank 28. Control relays may also be used to control fluid flow into and out of the tank. If, on the other hand, an empty condition cannot be tolerated and the actual fluid level is below low limit set point in memory 42, a signal is provided along line 50 to proportional control valve 22 to allow more fluid to flow into tank.
System 10 also provides a fail-safe mode of operation which provides a desired output, on display 60 for example, in the event of a system failure such as a power or equipment failure. In this case, the fail-safe mode becomes operable when the circuit shorts or opens along line 36. In a high fail-safe mode a high level (unsafe) condition will be simulated for the system. In the low fail-safe mode, the situation is reversed. In the case of a short or open circuit, the low fail-safe mode is implemented. If overfilling of the tank is to be avoided, the high fail-safe mode will be used. If an empty condition cannot be tolerated, a low fail-safe mode is required. As a result, filling and draining of the tank will be controlled in either mode. A computer program in microprocessor 20 is used to detect when system 10 is in a fail-safe mode and responds accordingly.
The functions of the program are basically shown in flow chart 100 of FIGS. 5A-B. Flow chart 100 describes the sequence of events that occur during the execution of the program a copy of which is enclosed and made a part hereof written in machine language for the 1802 microprocessor. The program first initialized memory locations by defining them and providing them with initial values. This is performed at the program initialization step 102. The program must first determine what mode it is operating in and this is examined at decision diamond 104.
There are a number of mode selections that can be made in the on/off mode but the outcome is fundamentally the same for all possible selections. Decision diamond 106 first requires a determination as to whether calibration must be performed. If calibration is not required, then the new input value will be compared to the prior set point values for determining whether system 10 should be on or off. This occurs at block 108. In block 110 the program will determine the high and low set point values depending upon the mode selection made. The level status of the present input valve will be made with relation to those high and low set point values. At block 112 the fail-safe switches are examined to determine the proper settings for each switch. The program then returns to the program initialization block 102. If one of the possible selections was made that brings the program into the continuous mode at decision diamond 104, then another sequence of events will occur.
In decision diamond 114 a determination of whether or not to calibrate will be made. If calibration is not required, then block 120 shows that the span between the high and low levels will be determined. In block 120a there is a determination of the display value from the current count and span. Then block 122 display value will be displayed after using a lookup table to obtain the scale. The analog representation of the display value is provided in block 124. The high and low set point values can now be switched into computer memory 42 for further continuous mode operation. Switching the low and high set point values in the computer memory takes place at block 126. Branching now occurs from this point in the program back to the first step of the sequence provided in block 108.
If calibration is required in either the on/off mode or the continuous mode, the sequence of events are essentially identical. First, a decision is made at decision diamonds 128a and 128b to determine if calibration can continue. If calibration continues then a time interval signal will be produced that is proportional to the capacitance between probe 12 and container 26. The time interval signal which is a function of the total number of oscillator pulses within the duration of the signals provided by multivibrator 14, is obtained by the program 20 as indicated by blocks 130a and 130b. With this data the program continues to perform either on/off calibration routines or continuous calibration routines at blocks 132a and 132b respectively. These calibration routines are continued until branching occurs to other portions of the program.
A test mode may also be selected that allows the program to test display 60 and other analog outputs and sensors as shown in block 134. As shown in block 136, if a sensor fails, for example display 60 shows a zero which suggests an empty container and analog outputs are provided at 4 milliamps which is the lowest value of a 4-20 milliamp range. Display 60 shows the same information when calibration fails to occur but a light is also provided for this condition. This is performed in the program as shown in block 136 of the flow chart.
Display device 60 may be used to accept a digital signal along line 59 within a range of from 0 to 100%, for example, to show the analog representation of the fullness of the tank in terms of percent fullness based on the range of the scale provided in extrapolator 46.
Once the probe and transmitter are installed in a tank and the two high/low set points stored in computer memory, the level control system will operate without further probe adjustment. This is especially important when the probe and transmitter are used in explosion proof installations. The probe/transmitter is, itself, explosion proof due, primarily, to its low energy use. Calibrations are required as the system is moved from one shaped tank to a different shaped tank although not when reusing the same tank. ##SPC1## | A level indicator control system including a microprocessor that controls the height and, therefore, the amount of the substance, such as fluid or granular solid, to be contained in a closed or open tank or vessel. The system provides calibrated digital or analog output that shows the extent to which the tank is filled with substance at substantially any level. A scale, in percent, each value representing the percentage of fullness of the tank, is produced after low and high limits, representing any low and high substance levels respectively, are provided to the microprocessor. The scale values are a function of the changes in capacitance between the stationary probe and the tank wall as the level of substance approaches or submerges the probe. The system finds its probe capacitance and sets its own high and low control set point limits automatically. Thereafter, the system uses the instantaneous probe capacitance and the capacitance values representing the high and low substance levels to provide the calibrated digital or analog output. For example, when the substance in the tank exceeds the high limit set point value, the control system prevents more fluid or granula solid from entering the tank. | 6 |
CROSS-REFERENCE TO RELATED APPLICATION
This application is a division of U.S. patent application Ser. No. 07/094,875, filed Sept. 10, 1987 now U.S. Pat. No. 4,926,863 issued May 22, 1990.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to implantable cardiac pacemakers; and more particularly to an activity-based pacemaker which automatically adjusts pacing rate according to a determination, from samples of detected movements of the patient indicative of exercise in successive equal intervals of time, whether the exercise is more vigorous or less vigorous than that which occurred during prior time intervals.
2. Relevant Background
Since the advent of the artificial implantable cardiac pacemaker, the aims of cardiac pacing have changed from the initial goal of simply providing a lower rate limit to prevent life-threatening asystoly, to the present-day broad objective of improving the overall quality of life of the pacemaker patient. Quality of life, in this context, pertains to the performance of the heart under widely varying metabolic and hemodynamic conditions. Patients with conventional single chamber pacemakers often lack adequate heart rate and cardiac output to sustain more than slight physical exertion, and consequently suffer severe limitations on activity and fitness. For patients with complete AV block sinoatrial node activity, the dual-chamber pacemaker can restore adequate adaptation of heart rate to exercise; but that solution serves only a relatively small portion of the pacemaker patient population, and such pacemakers are susceptible to disturbances.
As a result, numerous studies have been conducted over the years seeking to uncover parameters which act internal or external to the body for possible use in controlling pacemaker stimulation rate. The goal is to control the heart rate of a pacemaker patient in a manner similar to the intrinsic heart rate of a healthy person with a normal functioning heart, under various conditions of rest and exercise; which is to say, in a physiologically appropriate manner. Parameters for controlling the pacing rate heretofore studied and proposed in the patent and scientific literature include the QT time interval, which varies with the electrical depolarization and repolarization occurring during exercise (e.g., U.S. Pat. Nos. 4,201,219 and 4,228,803); respiration rate, and thoracic impedance changes arising from increased respiration with exercise, using external adhesive electrodes and an external pacemaker (e.g., U.S. Pat. No. 3,593,718 and European patent No. EP-A2-0135911); the blood pH balance (e.g., U.S. Pat. No. 4,009,721); the central venous oxygen saturation (e.g., U.S. Pat. Nos. 4,202,339 and 4,399,820); stroke volume (e.g., U.S. Pat. No. 4,535,774); nerve activity (e.g., German patent No. DE 28 09 091 and U.S. Pat. No. 4,201,219); and the central venous blood temperature (e.g., German patent No. DE OS 26 09 365).
Applicant's German Patent No. DE 34 19 439 and related U.S. application Ser. No. 747,111 ("the '111 application") discloses techniques for rate responsive pacing which utilize both absolute temperature values and relative temperature changes of the central venous blood of the patient under various physiological conditions, and which utilize separate algorithms defining heart rate as a function of blood temperature for states of rest and exercise, respectively, together with the decision rule for selecting which of the algorithms is appropriate at any given time.
Techniques for converting mechanical forces, accelerations and pressures into electrical energy and/or signals have also been proposed in the literature for use in biomedical technology. These techniques include the generation of electrical energy to power implanted devices from piezoelectric crystals and other mechanoelectrical converters responsive to movement of the individual (e.g., U.S. Pat. Nos. 3,659,615 and 3,456,134); the use of a piezoelectric crystal embedded in silicone rubber and implanted in the pleural space between lung and ribs, to detect the respiratory rate for controlling the pacing rate (see Funke's publication in Journal Biomedizinische Technik 20, pp. 225-228 (1975)); the use of a piezoelectric sensor for measuring cardiac activity (U.S. Pat. No. 4,428,380); detecting patient activity with an implanted weighted cantilever arm piezoelectric crystal, and converting the output signal of the crystal into a drive signal for controlling the rate of a cardiac pacemaker (U.S. Pat. No. 4,140,132); and using the amplitude of a band-passed signal whose high frequency content increases with patient movement in an activity-responsive cardiac pacemaker (e.g., U.S. Pat. No. 4,428,378).
The aforementioned prior art parameters and techniques suffer various disadvantages when used in an effort to control pacemaker stimulation rate. For example, control according to the QT principle cannot distinguish emotional influences on QT interval changes from exercise-induced influences, which leads to sometimes unwanted and more pronounced emotionally-induced increases in the patient's heart rate. The change of respiratory rate with exercise varies widely between individuals, although less so with minute ventilation. Also, a person may voluntarily alter his or her respiratory rate without exercise and thereby adversely affect pacing rate. The pH level of the blood is not truly representative of patient metabolism because the significant changes toward acidity occur only at the higher levels of exercise. Similarly, changes of the central venous oxygen saturation are not a satisfactory indicator because a considerably greater decrease occurs at the beginning of exercise, even low work-load exercise, especially in those patients with limited cardiac output or tendency toward congestive heart failure, while continuing exercise may produce only slight further decreases. The stroke volume exhibits variations based on the position of the body, that is, according to whether the patient is sitting, lying or standing, which are independent of the level of exercise. The detection of patient activity by means of a neurodetector for the carotid nerve, for example, has serious limitations because of the nature of the surgery and the level of patient discomfort from this type of implant.
The detection of the activity- or motion-induced forces within or on the body by means of a piezoelectric crystal, a microphone or other mechanoelectrical transducer exhibits the desirable characteristic of a fast response to the onset of exercise, but has certain serious disadvantages including the deleterious effect of noise disturbances external to the body, such as from nearby operating machinery, or emanating within the body, such as from coughing, sneezing, laughing, or the like. Accordingly, disturbances unrelated to exercise can affect the heart rate, when accelerometer-type detection is utilized for control of the pacemaker stimulation rate.
It has been assumed in the prior art that the maximum acceleration values detected by an activity-controlled cardiac pacemaker in a patient undergoing exercise occur in the range of the resonant frequency of the major body compartments such as the thorax and the abdomen, i.e. approximately 10 Hz (e.g., see Proceedings of the European Symposium on Cardiac Pacing, editorial Grouz, pp. 786 to 790, Madrid, 1985). Thus, the prior art teaches that the maximum sensitivity should be in the range above 10 Hz (e.g., see also, Biomedizinische Technik, 4, pp. 79 to 84, 1986, and the aforementioned U.S. Pat. No. 4,428,378).
SUMMARY OF THE INVENTION
The present invention pertains to an aspect of the cardiac pacemaker disclosed in the aforementioned application Ser. No. 07/094,875, which reliably generates stimuli at rates adapted to the overall metabolic state of the patient. According to the present invention, the stimulation rate of the pacemaker is responsive to the level of physical exertion of the patient, closely corresponding to the heart rate of a normal healthy person under the same conditions of physical exertion. The pacemaker preferably employs an accelerometer (activity or motion sensor) in the form of a miniaturized mechanoelectrical converter or transducer of suitably low power consumption, which is adapted either by virtue of its construction or by use of associated filter circuitry to pass signals in a frequency band which is preselected to avoid increased rates of stimulation in response to false indications of exercise.
The preferred embodiment of the pacer in which the present invention is implemented also advantageously employs a second sensor for detecting a parameter complementary to acceleration, for dual sensor confirmation of metabolic state and selective contribution to stimulation rate. As used herein, the terminology "complementary parameter" is intended to mean any physiological or other detectable parameter of the body or acting outside the body, whose characteristics of sensitivity and specificity to physical exercise contrast with and enhance the corresponding characteristics of the activity sensor.
Known activity sensing pacers have the advantage of providing a fast response to the onset of exercise, but the disadvantage of a substantial inability to respond to the instantaneous metabolic level of exercise. In contrast, a parameter such as the central venous blood temperature, for example, responds less quickly to the onset of exercise, but is highly specific with respect to the metabolic level of exercise. Thus, the two parameters may be used in combination in a rate adaptive cardiac pacing system to complement each other by mutually supplying what the other lacks.
Based on considerable data obtained from healthy subject test volunteers and, as well, from testing of cardiac pacemaker patients, the applicant has found, using a primarily linear frequency sensor, that contrary to the teachings of the prior art the maximum forces occurring with physical activity are in the range of the frequency of the individual's steps in walking. The maximum amplitude is observed with the individual walking, whether on a level surface or up and down stairs, and with running, in the range of 1 to 4 Hz depending on the speed of the walking or running. The amplitude of these motion signals far exceeds signals from respiration and heart beat.
Further, the amplitude of these signals in the range of the response curve (the walking frequency), measured using a mechanoelectrical transducer which is configured for or used together with circuitry selective in this frequency range, has a direct and largely linear relation to the work performed. When the amplitudes of these low frequency signals (up to about 4 Hz) increase there is also an observable increase in the amplitudes of higher-frequency signals in the range above 4 Hz, but the latter are considerably smaller than those of the low-frequency range signals arising from physical activity.
Applicant's investigations indicate that the maximum amplitude activity-sensed signals occurring with exercise such as walking, climbing stairs, running and bicycling, take place with rhythmical motions of the body and are found in the low-frequency range below 4 Hz. Housework such as cleaning, vacuuming and the like also exhibits a maximum amplitude in the low-frequency range. In contrast, amplitude maxima in the higher-frequency range are the result of sudden spasmodic movements which do not represent true metabolic exercise, and the indicia of those movements are readily excluded by limiting detection to only the low-frequency content, which correlates well with the metabolic demand of the body in true exercise.
Noise detected from outside the body such as when the patient is in close proximity to operating machinery, or arising from within the body such as when the patient coughs, laughs, sneezes or strains, displays amplitudes in the higher-frequency range up to about tenfold the amplitudes of signals in the same range attributable to true physiological exercise. Thus, the noise signals tend to swamp the activity-induced signals at the higher frequencies. Light knocks upon, bumps against or touching of the pacemaker are picked up by the internally mounted activity sensor and present impulse characteristics detected in the higher-frequency range, but are detected, if at all, with very low amplitudes in the low-frequency range up to 4 Hz. Also, because the duration of the pulse wave deriving from the propagation of the pulse with every heart beat is in the range of about 70 to 120 ms, it has an impulse characteristic with maximum amplitude in the higher-frequency range at about 10 Hz, despite the fact that the heart rate itself is in the range from 60 to 180 beats per minute (bpm) corresponding to a frequency of 1 to 3 Hz.
According to the applicant's measurements, riding in a car or on a bicycle on an uneven road surface produces some noise in the low-frequency range, but considerably below amplitude maxima detected within the higher-frequency range. In general, the ratio of activity-induced signal to disturbance-created noise in the low-frequency range is considerably better than in the higher-frequency range, and the low-frequency noise is readily discriminated from those signals representative of physical activity of the patient.
The present invention utilizes the low-frequency spectrum in performing reliable detection of signal amplitude maxima and minima with a relatively low sampling rate, versus the higher rate which would be required for the high-frequency range, with attendant considerable energy savings. This is important because of the limited energy capacity of implantable pacers.
A further important aspect of the applicant's findings is that rate control may be achieved with an activity sensing pacemaker using relative changes of amplitude of the processed activity-induced signal, rather than the absolute signal values, for adjusting the stimulation rate. This is quite different from the teachings of the prior art, which invariably relies on the absolute values. Use of relative changes avoids false triggerings caused by ambient noise since a rate increase is dictated only when the value calculated from the signal exceeds a predetermined activity baseline. The rate increase is a function not only of whether the predetermined baseline value is exceeded, but also of the rate at the time this criterion is met. Thus, the relative extent of the increase will be less with increasing pacing rate, i.e., the specific amount of the increase will be smaller at the higher rates. Still, both the absolute amplitude and the relative change of amplitude of the activity signal may be evaluated to determine a stimulation rate increase, in part because of the relatively slower response of the second complementary parameter.
An embodiment of a rate responsive cardiac pacemaker in which the stimulation rate is controlled by detecting a second complementary parameter as well as by use of an activity sensor allows the control to be optimized to avoid prolonged false triggerings which might be encountered using the activity sensor along. In a Fall 1985 presentation before the German, Austrian and Swiss Cardiological Society in Vienna, applicant discussed the possible use of a temperature sensor with an activity sensor of the type taught by the aforementioned U.S. Pat. No. 4,428,378 (see Zeitschrift fur Kardiologie, vol. 75, Abstract 69, 1985). An attendee of that presentation and his colleagues subsequently investigated whether the central venous blood temperature is a suitable measurable variable for use in combination with the specific activity control according to the latter patent (see Herzschrittmacher 6: 64 to 67, 1986).
The preferred embodiment in which the present invention is implemented goes considerably beyond the mere use of plural parameters in a pacemaker. Rather, in one of its aspects, the complementary parameter is used to limit a noise-related false triggering of a rate increase by a relative change in the signal level of the mechanoelectrical transducer, and the output signal of the transducer is used to determine whether an increase in the stimulation rate attributable to the value of the complementary parameter is appropriate. For example, if venous blood temperature is the complementary parameter, fever may be detected (or confirmed) in the absence of an activity (motion) signal from the transducer, and the stimulation rate increase held to an appropriate lower value. That is, the new rate may be based on the signal representative of the measured complementary parameter when the absolute signal level of the activity transducer is below a predetermined minimum. Absence of motion dictates not only an absolute rate, but a minimum rate determined by the state of the complementary parameter.
After physical exercise, the stimulation rate of the preferred embodiment is decreased to a quiscent base rate (resting rate) according to a fall-back program (i.e., a rate reduction routine) as a function of the drops of the signals from both sensors. However, a decrease in stimulation rate to this base rate may be inhibited so long as the processed absolute signal amplitude of the activity sensor exceeds a predetermined level indicative of body activity. Thus, rate control is provided using the low frequency band and the relative change of the transducer signal amplitude in that band; and the absolute signal amplitude of the low-frequency processed transducer output allows detecting absence of motion for rate control according to a baseline characteristic relating heart rate to the second parameter, or detecting the presence of motion for suppression of a rate fall-back program. The mechanoelectrical transducer may thereby provide fast response for rate control at the onset of exercise and change of the workload, a shift to a resting baseline control by the complementary parameter in the absence of an activity-induced signal, and prevent or limit rate reduction in the presence of an activity-induced signal characteristic of exercise.
A feature of the preferred embodiment is that a new baseline or threshold level for activity is established according to the specific inertia criteria or characteristics of the complementary parameter, which may be one of the exemplary parameters mentioned above or the natural sinus node activity in a dual chamber pacemaker. After a certain time interval (e.g., a few minutes) with no confirmation of the transducer signal by the complementary parameter sensor signal, the then-current activity signal amplitude is assumed to be the new baseline, zero or quiescent value of activity. Thereby, a prolonged improper rate increase from false triggering of the activity sensor is avoided even in a noisy environment.
If the transducer output signal is zero or less than a predetermined minimum absolute amplitude, and the detected value of the complementary parameter is increasing, the preferred pacer embodiment will initiate a fall-back program to return the stimulation rate toward a predetermined base or resting rate. Such circumstances indicate that the patient is not undergoing physical exertion, and that it is appropriate at this point to reduce the stimulation rate to the base rate. This feature may be utilized to discriminate and halt reentry tachycardias in atrial P-wave triggered DDD pacemakers.
Protection is provided against prolonged improper rate increases from false triggerings of the activity transducer, and against prolonged rate increases attributable solely to the sensed value of the complementary parameter. Furthermore, the extent of rate control accorded to that complementary second parameter can differ according to the nature of the signal (or lack thereof) deriving from the activity transducer.
The mechanoelectrical transducer may be a piezoelectric, piezoresistive or piezocapacitive sensor of the semiconductor type, which can even be integrated with signal processing circuitry in a silicon chip. Such integrated circuits are manufactured using conventional semi-conductor process technology. By fabricating the sensor with appropriate geometrical configuration, the sensor itself can provide the desired frequency bandpass characteristics to capture the proper signal. For example, the transducer may comprise a vibratory cantilever arm of material and length selected to provide it with the desired resonant frequency.
According to the invention, an implantable variable rate activity-based pacemaker detects movements of the patient, discriminates between detected movements indicative of physical exercise and of non-exercise, samples the detected movements indicative of exercise in successive equal intervals of time to determine whether the exercise is more vigorous or less vigorous than that which occurred during prior time intervals, and adjusts the pacing rate accordingly.
In a process according to the invention, the patient's mechanical movements are detected and converted to a signal whose frequency and amplitude vary with rapidity and intensity of the detected movements, the signal is selectively limited to appreciable amplitude values in the frequency range below 4 Hz, maximum and minimum signal amplitude values are detected in each time interval, and the differentials thereof are stored, averaged over a predetermined number of consecutive time intervals and compared with the average over a corresponding number of immediately preceding consecutive time intervals.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other objects, aspects, features and advantages of the present invention will become more apparent from a consideration of the ensuing detailed description of a presently preferred embodiment thereof, taken in conjunction with the accompanying drawings, in which:
FIG. 1 is a block diagram of a cardiac pacemaker according to the invention;
FIG. 2a is a schematic diagram of a frequency spectrum of the low-pass (band-pass) signals of a mechanoelectrical transducer (activity sensor) used in the pacemaker of FIG. 1;
FIG. 2b shows a Fourier analysis with respect to the frequency and amplitude of the signals from the mechano-electrical transducer for the activity of slow walking;
FIGS. 2c through 2f each show frequency and amplitude spectra for different types of activity and disturbances;
FIGS. 3 to 7 and 10 are diagrams of signals developed in the pacemaker of FIG. 1 for indicated types of activity;
FIG. 8 is a flow chart of the functioning of the cardiac pacemaker of FIG. 1; and
FIGS. 9a and 9b are respectively a front view and a cross-sectional view of one example of a mechanoelectrical transducer which could possibly be used in the pacemaker of FIG. 1.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to FIG. 1, a cardiac pacemaker 1 includes a case 2 in which the various components are housed, including evaluation circuitry 10a and activity sensor (mechanoelectrical transducer) 3. The circuitry within case 2 is connected via a conventional connector 4 to a pacing lead 5 with a stimulating electrode tip 6. The pacing lead(s), for example, is of the endocardial catheter type for insertion intravenously to position the stimulating electrode(s) relative to excitable myocardial tissue in the appropriate chamber(s) of the right side of the patient's heart. The pacemaker may be arranged in conventional fashion for unipolar or bipolar stimulation, and may include known sensing electrode(s) and processing circuitry therefor as well.
A second sensor 7, electrically connected to the pacemaker circuitry via a suitable connector 4a, for example, is provided for detecting a second complementary physiological parameter, such as the natural atrial rate, the QT interval, the pH value of the blood, the blood oxygen saturation, the respiration, the central venous blood temperature, or other recognized parameter of or acting on the body, whose value is related to heart rate. In the preferred embodiment, the central venous blood temperature is chosen as the complementary second parameter and will be referred to in that respect throughout the ensuing description, but the invention is not limited to the use of blood temperature. By using blood temperature as the complementary parameter all of the teachings of the '111 application are readily and advantageously employed. Sensor 7 in this embodiment, therefore, may be a thermistor or other suitable temperature sensing element located in the pacing lead 5, in the manner described in the '111 application, for sensing the blood temperature in the atrium or ventricle of the right side of the patient's heart.
The implanted pacemaker case 2 further houses a battery 8; a pulse generator 9, whose pulse rate is controllably variable, for generating the stimulating pulses to be delivered to pacing electrode 6 for stimulating the patient's heart; evaluation circuits 10a, 10b for processing and evaluating the signals deriving from activity sensor 3 and temperature sensor 7, respectively; a memory 11 for storing data, such as programmed values in conjunction with a conventional external programmer and other data of the type to be described, including a baseline curve and exercise curves (algorithms) representing heart rate as a function of blood temperature, as set forth in the '111 application; and a logic circuit 12 for controlling the sampling of signals from the sensors and the rate of the pulse generator.
Activity sensor 3 is a small mechanoelectrical transducer, preferably of a type mentioned above, which is either fabricated in a conventional manner to provide an inherent frequency band characteristic selected according to the teachings of the present invention, or is coupled to a filter circuit to pass signals in that selected band. The frequency spectrum of the band-passed signals from activity sensor 3 is represented in FIG. 2a, with low pass filtering producing a rapid drop-off at frequencies exceeding 4 Hz, and with high pass filtering to eliminate DC and frequencies below the 0.3 Hz level.
In FIGS. 2b to 2f, the output signals of sensor 3 are analyzed for several different types of activity. FIG. 2b is a Fourier analysis of the processed signals of the activity sensor showing frequency measured in Hz and amplitude measured in dB, detected in a slowly walking test subject. FIG. 2c charts the amplitude relative to time of the low-pass signal (i.e., in the band from about 0.3 Hz to 4 Hz) processed from the activity sensor for successive intervals of rest, walking, running, walking and return to rest by the subject. FIG. 2d illustrates, in three separate charts, the unfiltered complete output signal of the activity sensor (upper chart), the high-pass portion (i.e., above the selected band) of the signal (middle chart), and the low-pass portion of the signal (lower chart), detected from a walking subject in which successive intervals of noise are encountered by touching of the pacemaker, coughing and laughing by the subject.
As will be observed from FIG. 2b, the frequency spectrum for movement of the subject by foot indicates a clear maximum amplitude at a frequency of approximately 2 Hz; and significantly declining signal amplitudes in the range exceeding 4 Hz. FIG. 2c shows an increase in the amplitude of the low-pass activity signal with increasing exercise as the subject goes from walking to running, and an amplitude decrease as the subject returns to walking and ultimately to a state of rest. FIG. 2d clearly demonstrates that the low-pass activity signal is virtually unencumbered by the noise generated from impact on the pulse generator case, coughing, laughing or the like, the signal indicative of walking being cleanly detected. In contrast, the higher frequency range is significantly affected by that noise, so much so that the signal representative of the walking is buried in the noise.
FIGS. 2e and 2f show the signal amplitudes over time for the entire frequency spectrum (upper chart), the high-pass portion (middle chart), and the low-pass portion (lower chart), when the subject is riding in a car and bicycling on an uneven road, respectively. Here again, it is abundantly clear from the test results that the frequency range below 4 Hz provides an indication of true activity, virtually uninfluenced by any noise peaks. In FIG. 2e, the higher frequency range is replete with noise including spikes at the resonance of the moving car. In FIG. 2f, the noise is also pronounced at the higher frequencies, with a more homogeneous noise distribution attributable to the uneven road surface traversed by the bicycle. In both cases the true activity signal is masked. It will thus be apparent, contrary to the teachings of the prior art, that processing only the lower frequency band of the activity sensor output provides a considerably more accurate indication of true exercise while avoiding the many false triggerings of rate increases by the pacemaker which can result from noise detected in the higher frequency band.
FIG. 3 shows the behavior of the cardiac pacemaker of the present invention when subjected to a false triggering attributable to noise, encountered while the patient is riding in a car for example. Part (f) of FIG. 3 and also of similarly formatted FIGS. 4 to 7 indicates the nature of the exercise workload. In each of these FIGS. the time scale is partly compressed and does not correspond to actual time. For example, the interval between times t1 and t2 is typically only two or three seconds in duration, whereas at least some of the subsequent time intervals may be of several minutes duration each.
In the example of FIG. 3, the "exercise" is fictitious, with the signal detection resulting strictly from noise. Part (a) shows the processed output of activity sensor 3 for the aforesaid low frequency band. Up to time t1 the pacemaker patient is merely sitting in the stationary car; hence, no signal or only small signal variations (attributable to slight movement of the patient in the idling vehicle, for example) are detected. At t1, the car starts moving and a higher signal level is detected. It is important to observe that the signal amplitude is exaggerated for the sake of explaining this example; as was observed in FIG. 2e, the low frequency band is quite effective to filter disturbances arising from the moving car.
Processing of the signal after filtering may be accomplished in different ways. For example, the evaluation circuit 10a may be adapted to operate on the band-passed signal over successive blocks of time of, say, three seconds each. The difference between the maximum and minimum signal amplitudes is calculated for samples taken at predetermined intervals of, say, 300 milliseconds each. The calculated amplitude difference is then added to the calculation for the previous sample for all X samples of Block 1 (i.e., the first three second period, in this example), and the value obtained is then averaged for Block 1 by dividing that value by the number of samples taken. If the difference between that average and the average for Block 2 (i.e., the next three second period) exceeds a predetermined activity baseline related to units of gravity, and if this is confirmed over the next few blocks of time, it is indicative of activity or of a significant increase of activity (additional activity). This is the post-filtered signal processing technique employed in the preferred embodiment of the invention, although various other suitable techniques will be apparent to the skilled artisan. In this manner, random or spasmodic movements which might otherwise be regarded as exercise can be disregarded.
Referring again to part (a) of FIG. 3, the jump in the filtered activity signal occurs at time t1 (or an instant later depending on the response time of the activity sensor). The processed data is compared with predetermined baseline or threshold values of activity A1, A2, and so forth, each of which may be freely programmable and stored in the memory 11 (which, incidentally, was also used to store sampled values for the aforementioned data processing). The initial activity thresholds may be selected according to the particular patient and the type of accelerometer (activity sensor) employed for the pacemaker. By way of example, 0.15 g (unit of gravity) was deemed an acceptable level indicative of patient activity for one test subject, using an embodiment of an activity sensor for which that level of movement produced a signal level of about 60 millivolts.
If the previously described processing calculation exceeds the first threshold A1, the logic circuit 12 controllably initiates an increase in the rate at which stimulating pulses are generated by the pulse generator 9 by an amount of, say, 15 pulses per minute (ppm, equivalent to bpm). If the second threshold A2 were exceeded at t1, the pulse rate would be increased by a greater amount, say, 25 ppm. This rate increase is accomplished as follows. Logic circuit 12 responds to threshold A1 having been exceeded at t1, by initiating at t2 a preset timing function of a rate controller 21 to which it is connected within housing 2, to increase the pacing rate of the pulse generator 9 by 15 bpm. This timing function produces a predetermined transition to the higher pacing rate, as represented in part (b) of FIG. 3. If there is no further significant change in the processed signal calculations as described above, this increased stimulation rate will continue in effect. At the same time that the rate increase is initiated, the exceeded activity threshold A1 is designated as the new activity baseline, and a higher activity threshold A1' (and A2', etc.) is set from which to determine additional activity, as will be further explained presently.
At any time that the absolute amplitude of the activity signal drops to 25% of the activity threshold which was exceeded to cause the rate increase, the logic circuit initiates a fall-back program through another timing function of rate controller 21 to gradually reduce the stimulation rate of the pulse generator back to a preprogrammed base rate. As shown in FIG. 3(f), the car comes to a stop at t5. The absolute level of the detected activity signal drops to 25% of activity threshold A1 an instant thereafter (FIG. 3(a)), and the pacing rate is decreased commencing at that time (FIG. 3(b)).
However, the present invention also serves to avoid prolonged rate increases from false triggerings of the pacemaker as a result of high levels of noise in the filtered output of the activity sensor, even in those instances where the noise is present in the low frequency band and is not rejected by the aforementioned signal processing calculations. To that end, the logic circuit 12 actuates a timer 22 at t2, coincident with the triggering of the rate increase via rate controller 21, to commence timing a predetermined period (FIG. 3(b)) whose duration is preset according to the response time of the selected second complementary parameter to the onset of exercise or to abrupt changes in level of exercise. In the presently preferred embodiment, where blood temperature is the complementary parameter, the period of timer 22 may be set, for example, at two to three minutes. In general, sensors of the physiological parameters mentioned earlier herein are less sensitive to the onset of exercise than an activity sensor, but as previously noted herein, each of these other parameters is a suitable complementary parameter to acceleration because of their greater specificity in indicating the varying level of ongoing exercise. If one of these other parameters were used in place of blood temperature, the timer 22 period would be set accordingly. The duration of the timer period is important because if, during that period, the stimulation rate dictated by the second complementary parameter exceeds the rate dictated by the activity signal, the latter relinquishes and the former assumes control of the stimulation rate. On the other hand, if the second complementary parameter fails to assume such control, this constitutes a lack of confirmation of the activity signal and an indication of no true activity or of insufficient activity to warrant the rate increase. Accordingly, in the latter circumstance the logic circuit 12 actuates the rate controller 21 to initiate a rate reduction routine (fallback program) at the end of the period of timer 22.
The blood temperature measured by thermistor 7 over the timer period is represented in FIG. 3(c). The stimulation rate is calculated from the measured blood temperature as described in the '111 application, and is represented in FIG. 3(d). Of course, in this example the "exercise" is fictitious, and consequently the temporal increase, if any, in the blood temperature would be insufficient to produce a stimulation rate other than is commensurate with the baseline resting curve. In fact, there is no substantial change in the blood temperature according to FIG. 3(c), and therefore virtually no change in the rate determined from the blood temperature as shown in FIG. 3(d). Hence, at time t3, when the timer period expires, logic circuit 12 initiates the rate fallback program of rate controller 21 to gradually reduce the stimulation rate of pulse generator 9 to the programmed base rate at t4. This assures that the patient will not be subjected to improper rate increases as a result of false triggerings for more than the relatively short duration of the timer period, rather than experiencing a prolonged rate increase, for example, over a four hour car ride.
If the evaluation of the filtered activity sensor output indicates a reduction in the averaged maxima and minima of the signal by 75% or more to a value of 25% or less of the activity threshold which has just been exceeded, it is assumed that exercise has ceased. At that point, the logic circuit will initiate the fallback program of rate controller 21 to return the pulse rate of pulse generator 9 to the base rate. The various threshold values and the criterion of reduction of below last-exceeded activity threshold may be selected (programmed) according to the individual patient.
The arrangement of the diagrams in FIG. 3 is repeated in FIGS. 4 to 7, inclusive. In each FIG.: part (a) represents the filtered low-frequency band output signal of activity sensor 3; part (b) illustrates the stimulation rate (heart rate) attributable to the signal of part (a); part (c) shows the value or the signal representative thereof for the second complementary parameter--in the presently preferred embodiment, the blood temperature detected by sensor 7; part (d) represents the stimulation rate determined according to the value shown in part (c); part (e) shows the effective stimulation rate derived from both parameters (activity and blood temperature); and part (f) schematically represents the exercise level or workload.
FIG. 4 is a diagram representing the behavior of the pacemaker for a patient who commences walking for a period of time and then returns to a state of rest. Part (f) indicates that the exercise starts at time t1, and is thereupon detected by the activity sensor (part (a)). The filtered signal amplitude is processed by the evaluation circuit 10a and, after a brief interval, the calculated value is found to exceed activity threshold A1. Accordingly, pulse generator 9 is adjusted via rate controller 21, under the control of logic circuit 12, to increase the pacing rate by 15 bpm commencing at time t2, as shown in FIG. 4(b). At time t4, the exercise ceases and this is recognized at time t5, when the calculated value of the processed activity signal has dropped to 25% of the activity threshold A1. In those circumstances, if the rate control were based strictly on the output of the activity sensor the stimulation rate would be reduced gradually toward the programmed base rate under the rate reduction routine of rate controller 21, as was described in connection with FIG. 3.
Here, however, the blood temperature increases with the exercise, after the characteristic dip at the onset thereof, and continues to increase until it reaches a steady state value FIG. 4(c). At time t3, before the timer 22 period has expired, the stimulation rate determined according to blood temperature exceeds the rate determined from the activity signal (FIG. 4(d)). Thereupon, the detected blood temperature becomes the rate-determining parameter and the stimulation rate is increased according to the blood temperature (FIG. 4(e)), under the control of the logic circuit and the rate controller. This situation continues, with rate determined by blood temperature, until the exercise ends at t4. The blood temperature begins dropping off rapidly (FIG. 4(c)), and, with it, the stimulation rate begins to decline (FIG. 4(d) and (e)). At time t5, the value calculation from the processed activity signal drops to 25% of activity threshold A1, instituting the fallback program according to that parameter as well, and the combined stimulation continues its decline to the base rate (FIG. 4(e)).
FIG. 5 illustrates the behavior of a pacemaker according to the invention when the patient undergoes gradual increases of exercise, in the stepped manner shown in part (f). Initially, with the patient at rest, the pacing rate is maintained at the base rate. At t1, the patient begins walking, and, in response to detection of the rhythmical movement, the activity sensor generates a signal which is filtered in the frequency band of interest as shown in part (a). The signal is then processed to calculate the average difference between amplitude maxima and minima for a sequence of samples over the selected time interval, as described earlier. At time t2, the evaluation circuit determines that the calculated average exceeds activity threshold A1, and, in response, logic circuit 12 increases the stimulation rate by 15 bpm via rate controller 21, and also actuates timer 22 (FIG. 5(b)). The exceeded threshold A1 is thereupon stored in the memory 11 as the new baseline for activity, and a new higher activity threshold A1' is established (FIG. 5(a)). The latter is also stored in the memory, along with all other data to be utilized or operated on including base stimulation rate and the current increased rate. As a consequence of the establishment of the new activity baseline A1 and new activity threshold A1', no additional activity will be deemed to have occurred (and thus, no activity signal-induced rate increase will be initiated) until threshold A1' is exceeded by the average peak-to-peak value of the processed activity signal.
At time t5, the patient goes from walking to running (or from walking at a slow pace to walking at a faster pace, as another example). At time t6, it is determined that the calculated value of the processed activity signal exceeds current activity threshold A1', thereby initiating another increase in the pacing rate, e.g., by 10 bpm (FIG. 5(b)), the establishment of the now exceeded threshold A1' as the new activity baseline and of a higher level of activity as the new activity threshold A1" (FIG. 5(a)), and the restart of timer 22 (FIG. 5(b)). A similar set of events occurs each time the then-current activity threshold is exceeded. In this way, the patient is spared the possibility of prolonged rate increases resulting from false triggerings, but will be subjected to the appropriately higher stimulation rates when actual exercise or a change in exercise level is detected. Put another way, the patient will not experience repeated increases in stimulation rate as the signal level hovers about the same activity threshold, but instead a new higher threshold will be applied upon each rate increase.
At time t9, the patient stops running and again assumes a resting state (FIG. 5(f)). The cessation of activity is sensed and, at time t10, the calculated value of the processed activity signal has dropped to 25% of the last exceeded threshold A1' (FIG. 5(a)) which led to the previous double rate increase (initially 15 bpm and then another 10 bpm). In response, the fallback program is initiated for gradual reduction of the stimulation rate toward the base rate (FIG. 5(b)).
The foregoing discussion of FIG. 5 assumes rate control by the activity signal only. However, as shown in FIG. 5(c), the blood temperature responds to the onset of exercise at time t1 by dropping slightly and then rising until, at t3, it is at a value determinative of a pacing rate exceeding that of the activity signal-induced rate (FIG. 5(d)). Since t3 is within the timer period, the stimulation rate control is thenceforth dictated by the sensed blood temperature, commencing from the previously initiated rate increase of 15 bpm above the base rate (FIG. 5(e)). The blood temperature rises to a steady state value during the first stage of exercise, which is reflected in the combined stimulation rate until time t6, when the aforementioned second activity signal-induced rate increase of 10 bpm occurs. That new stimulation rate is maintained until t8, when the blood temperature-induced rate surpasses this activity signal-induced increased rate within the restarted timer period (FIG. 5(d)). The sensed blood temperature again assumes control of the pacing rate as the temperature continues to rise to a new steady state value during the second stage of exercise.
After the patient stops running at time t9, and this is recognized from the processed activity signal at t10, the combined stimulation rate begins a gradual drop under the control of the fallback program (FIG. 5(e)), as previously described. At that time, the blood temperature has begun to drop from its relatively high level, and at t11 the temperature commences to drop at a faster pace with a concomitant stimulation rate, but still somewhat slower than the rate according to the fallback program. The sensed blood temperature then again assumes control of the rate reduction toward the base rate. In this manner, it is assured that the pacing rate reduction meets the physiological requirements of the patient to the usual after-effects of heavy exercise, including the body's demand for replenishment of depleted oxygen, which are better accommodated by rate control under the more gradual decrease of the blood temperature. If the patient had stopped exercising before the detected value of the blood temperature had assumed or reassumed control of pacing rate from the activity signal, the stimulation rate would have returned to the base rate strictly according to the fallback program instituted in response to the drop in calclated value of the processed activity signal. However, that would be compatible with the physiological needs of the patient because, in those circumstances, the exercise session would not have extended beyond the relatively short period set by the timer 22.
FIG. 6 provides another example of exercise with increasing workloads, and also with decreasing workloads, as shown in part (f). From the descriptions of FIGS. 3, 4 and 5, it will be apparent that an activity signal-induced rate increase takes place at time t2 (FIG. 6(e)) in response to commencement of patient exercise at time t1 which exceeds the initial activity threshold. The blood temperature-dictated stimulation rate takes control at time t3 and continues to t5, when the output of the activity sensor is recognized as indicative of additional exercise (because the new activity threshold was exceeded at t4), and the rate is increased. At t6, the rate determined from the blood temperature again assumes control.
At time t7, the level of exercise abruptly decreases, and is detected by the activity sensor, but exercise does not cease entirely and the calculated value of the processed activity signal remains higher than 25% of the last-exceeded activity threshold. Accordingly, the fallback program would not reduce the stimulation rate to the base rate, but only by an amount proportional to the decrease of the activity signal. That is, the reduction in heart rate (-HR) is a function of the decrease in activity (-activity), based on the activity level observed after the decrease. If, for example, the cumulative activity-induced rate increase up to time t6 was 25 bpm, and the activity at t8 is 40% of that at t6, the rate at t8 would be reduced by 15 bpm (i.e., 60% of 25 bpm) and would still remain 10 bpm above the base rate (FIG. 6(b)). In terms of the stimulation rate resulting from both the activity signal and the blood temperature value, the rate reduction begins at t8 under the fallback program until the point at which the blood temperature-induced rate takes over, followed by the impact of the next fallback program at t10, when the calculated value of the activity signal has dropped to 25% of the last-exceeded activity threshold (FIG. 6(e)).
FIG. 7 reflects a situation in which the activity sensor detects exercise at t1 and a cessation of exercise at t4, corresponding to that of FIG. 4. Here, however, the sensed value of the blood temperature (or other slower reacting second complementary parameter) remains at a relatively high value (FIG. 7(c)), for example, because the patient has become feverish or because of defective measurement. At time t5, the timer 22 is started, commencing the running of the preset period, and the fallback program is initiated (FIG. 7(b)), as previously described. The stimulation rate is gradually reduced toward the base rate (FIG. 7(e)), but does not fully return to the base rate because of the contribution of the blood temperature-induced rate. However, for purposes of a rate decrease, both the absolute amplitude of the activity signal and the relative changes in amplitude thereof are determined and assessed with respect to the value of the second complementary parameter. From this, it is seen that at time t7 the absolute amplitude of the activity signal is less than a preselected minimum level, and therefore fails to confirm rate indicated by the blood temperature level. Accordingly, when the timer period expires, the fallback program resumes to reduce the rate to the predetermined base rate. As previously noted, the timer period is set according to the selection of the second complementary parameter and the sensitivity of that parameter to exercise. Thus, the use of two parameters in this manner permits control of stimulation rate without improper tachycardia despite a slow response, false triggering or an erroneous reading.
FIG. 8 is a flow chart of the operation of a pacemaker according to the invention. If no activity is detected, the stimulation rate is held at the base rate, which may be influenced by the complementary parameter. If activity is detected, the maximum and minimum amplitudes of the filtered activity signal are evaluated, and if the current activity threshold is exceeded the stimulation rate is increased accordingly and is held at the increased rate. The timer is started at the instant of the increase, and the detected value of the complementary parameter is monitored to determine whether it will influence this rate. At the same time, the exceeded threshold becomes the new activity baseline and a higher activity threshold is established that must be exceeded for additional activity to be detected.
If the calculation of average maximum and minimum amplitudes of the activity signal from several samples taken over successive predetermined time intervals exceeds the new higher activity threshold, the stimulation rate is again increased and held, and the timer is restarted to establish the period within which the influence of the complementary parameter is assessed once again. This process continues with each determination that additional activity has occurred. The increase in stimulation rate is effected in steps which decrease in size with the higher instantaneous rates.
If the logic determines that there is no additional activity, the activity sensor output continues to be evaluated to assess whether there is ongoing exercise, and if there is none, the fallback program is commenced to reduce the rate toward the base rate, which again may be influenced by the second complementary parameter. If there is ongoing exercise without decreasing level, the rate is held until additional activity or a decrease in the exercise level is detected. If a decrease, the stimulation rate is decreased accordingly. If the calculation of the processed activity signal amplitude drops to 25% of the previously exceeded activity threshold, the stimulation rate is reduced to the base rate, but if the drop is less than 75% the reduction in rate is a function of the delta (i.e., the amount of the drop).
The cycle repeats itself with each detection of patient exercise (including any false triggerings as described earlier herein). After each new occurrence (e.g., onset of exercise, increase in exercise, decrease in exercise, cessation of exercise) the timer is restarted to establish a new period during which to assess the influence of the complementary parameter on rate control.
FIGS. 9a and 9b illustrate an exemplary embodiment of a mechanoelectrical transducer which might be used in the pacemaker of the invention, but is to be emphasized that any transducer having the characteristics described earlier herein may be employed satisfactorily as an activity sensor. Transducer 31 has an integrated signal filter circuit 32, to provide the proper frequency pass band. The unit 31 comprises a silicon monocrystalline substrate 33 with a 1-0-0 orientation of the crystal planes. A p+ epitaxial conductive layer is formed on the surface of the substrate, followed by a polycrystalline silicon layer 34 sandwiched between passivating layers 35 of silicon dioxide. By anisotropic etching, a cavity 36 is formed in the substrate 33, and portions of layers 34, 35 are removed to form a rectangular plate 37 connected by four arms 38 to the corners of cavity 36. The rectangular plate 37 with arms 38 forms the element responsive to acceleration. A further layer 39 is deposited on the structure, with an opening extending contiguous with the perimeter of cavity 36, to permit axial movement of the rectangular plate on the arms. Finally, a protective layer 40, e.g., a glass plate, is placed over the structure. The integrated circuit 32 for processing the signal generated by movement of the rectangular plate 37 via arms 38 may be fabricated in the silicon layers by conventional semiconductor integrated circuit process technology.
FIGS. 10a to 10d illustrate test results using a cardiac pacemaker according to the invention, in which central venous blood temperature of the patient was selected as the second complementary parameter. The tests were performed on a healthy person connected to (but not paced by) an external pacemaker otherwise conforming to the principles of the present invention. The natural (intrinsic) heart rate HR int of the subject while undergoing exercise was recorded on a strip chart and compared to the similarly recorded stimulation rate HR stim generated by the pacemaker pulse generator as controlled by the control system of the present invention. The "paced heart rate" was detected at the lead connections of the pulse generator.
The upper three diagrams of each FIG. were recorded as a function of time in minutes. The lowermost diagram of each FIG. (i.e., below the upper three diagrams) is indicative of the exercise regimen performed by the subject, for which the other diagrams of the respective FIG. were obtained. The uppermost of the three diagrams of each FIG. indicates the measured output of the mechanoelectrical transducer stated in digitized representations from a computer in units g related to gravity (curve g) and the measured values from a blood temperature probe in °C. (curve T). The middle diagram of each FIG. shows the heart rate HR g calculated from and according to the curve g, and HR T calculated from and according to the curve T, both heart rates being in units of bpm, as calculated independently of each other by the circuitry of the control system. The lower of those three diagrams of each FIG. shows a curve of the intrinsic heart rate of the subject (curve HR int ), and the stimulation rate (curve HR stim ) as calculated by the control system of the present invention by combining the heart rates HR g and HR T according to the principles described above.
In FIG. 10a, the subject underwent a treadmill test in which he was subjected to different speeds and different inclines (grades) by the treadmill. It will be observed that the stimulation rate curve closely matches the natural heart rate curve virtually throughout the test regimen.
In FIG. 10b, the test subject underwent increasing and decreasing exercise on an exercise bicycle. It is interesting to note the increase in curve g in the interval from 16 to 20 minutes despite the decrease in the level of exercise, which is also apparent from the blood temperature curve T. This clearly shows that the test subject was tiring, and moved more on the bicycle notwithstanding that the metabolic expenditure was decreasing. Nevertheless, the curve of stimulation rate constituting a combination of the rates dictated by the activity signals and the sensed blood temperature values in the manner earlier mentioned herein, again closely corresponds to the curve of the subject's natural heart rate over time.
In FIG. 10c, the test subject walked continuously at a speed of 4.2 kilometers per hour on a treadmill with an upward grade of 6%, for a period of extended duration. At about 25 minutes, the heart rate derived from the detected central venous blood temperature values fell somewhat below the rate derived from the activity values, but the combination of these rates resulted in a stimulation rate curve which again closely approximated the subject's natural heart rate curve with time.
Finally, FIG. 10d shows the test results in which the subject underwent a treadmill test at increasing speeds and grades (constantly increasing workload), with a sudden cessation of exercise at the greatest speed and grade. As in FIG. 10b, the HR T curve was noticeably different from the HR g curve. In this test, the activity threshold values were exceeded twice. The determination of rate according to the activity signal is clearly observed at the onset, and the combined stimulation rate curve again closely duplicated the subject's natural heart rate curve over the test period.
While a preferred embodiment of the invention has been described, it will be apparent to those skilled in the art from consideration of the disclosure herein that various modifications may be implemented without departing from the inventive principles. Again, by way of example of modifications falling within the scope of the invention, the second parameter may be respiration, minute ventilation, stroke volume, blood oxygen saturation, blood pH balance, Q-T interval, or any of other known or contemplated parameter, or the time rate of change of any such parameter. Accordingly, it is intended that the invention be limited only by the appended claims. | An activity-based variable rate pacemaker senses motion in a preselected low frequency range to detect physical activity of the patient and produce an electrical signal having amplitude maxima and minima representative of the speed and intensity of the physical activity. The electrical signal is selectively limited to appreciable amplitude values for detected physical activity which is related to true physical exercise by the patient, in contrast to detected physical activity which is related to internal and external disturbances on the patient. The amplitude maxima and minima of the selectively limited signal are detected in successive equal intervals of time, the results obtained for consecutive blocks of time each containing the same number of successive equal intervals of time are compared to determine whether the physical exercise is more vigorous or less vigorous than that determined for a predetermined number of immediately preceding blocks, and the pacing rate is adjusted accordingly. The amplitude maxima and minima are sampled at a relatively low rate to conserve energy, and the time intervals are about 300 milliseconds each. | 0 |
BACKGROUND OF THE INVENTION
The device of this invention is designed for use in a bar tacking sewing machine. Bar tacking is the term used to describe the sewing of small stitch patterns which are generally used for reinforcing joints in shoes and other garments. These patterns are generally limited to a specific number of stitches in the range of from 10 to 100 stitches per pattern and cover only a small area of the workpiece. The operation is performed by moving the workpiece under the needle and this motion is achieved automatically by means of a work clamp which is mounted for movement along two axes relative to the needle. Work clamp movement is controlled by a style or feed cam which is operatively linked to the clamp. The style cam is generally driven by means of a shaft connected to the main needle bar drive shaft through a gear train. Thread cutting is controlled by a second cam connected to the same shaft but mounted opposite to the style cam.
Generally, the work clamp of this type of machine consists of a mechanically operated spring biased device which squeezes the workpiece between upper and lower clamping elements. The lower element is usually fixed in position with the upper element being forced downward by a spring which may be released by a lever associated with the thread cutting operation. The clamping elements have openings or windows which allow access to the workpiece by the sewing head. The pattern which is to be sewn is stitched within this opening. The upper clamping element may be split into a pair of separately releasable members to facilitate the clamping and registration of a workpiece which consists of multiple parts.
By operating the clamping mechanism in association with the thread cutter through a cam, a very rigid sequence of events are forced into the sewing operation, namely, the workpiece will be unclamped immediately after the thread is cut without exception. This partially defeats the flexibility which is desired on automatically controlled machines where workpiece movement and collateral operations are under electronic control. In addition, where a dual element clamp is used, only a limited amount of separate movement can be achieved.
Specifically, in those instances where it is desired to sew several distinct designs in one pattern, it is possible that the thread will be cut repeatedly after each design. Unclamping the workpiece after each design would result in a loss of registration of the parts and this would require costly operator involvement and loss of time.
The clamp of this invention, therefore, releases the mechanism from the control of the knife actuating lever and provides separate pneumatic actuators which may be controlled automatically. For further ease of use quick change fittings are provided on the upper and lower clamping elements to allow fast removal and replacement when different patterns are to be sewn.
BRIEF SUMMARY OF THE INVENTION
The clamping device of this invention is designed to be actuatable independently from the other collateral functions of a bar tacking sewing machine such as thread cutting. To accomplish this, pneumatic cylinders are operatively connected to the dual clamping feet through bell crank levers to provide the release motion of the clamp. The bell crank levers engage the biasing springs of the clamp which are connected to the clamping feet. This motion may be triggered automatically through the control system of the machine or manually through a treadle switch. To increase the flexibility of the clamp operation quick disconnect fittings are used to connect the clamping feet and the feed plate to the clamp.
DESCRIPTION OF THE DRAWING
This invention is more fully described in conjunction with the appended drawing and in said drawing:
FIG. 1 is a perspective view of a bar tacking sewing machine showing the workpiece clamp of the prior art;
FIG. 2 is a side view of a bar tacking sewing machine showing the clamp of the subject invention;
FIG. 3 is a perspective exploded view of the clamp assembly of this invention;
FIG. 4 is a partial side view of the clamp showing the unclamped position;
FIG. 5 is a partial side view of the clamp showing the clamped position;
FIG. 6 is a partial section view of the clamp feet showing the quick disconnect fittings; and
FIG. 7 is a block diagram of a control system for this sewing machine utilizing this invention.
DETAILED DESCRIPTION OF THE INVENTION
Prior Art
The function of bar tacking is generally performed on a standard type sewing machine which is adapted to the purpose by the addition of a work clamp for holding and moving the workpiece through the tack pattern. This movement is accomplished automatically by means of a style cam operatively connected to the work clamp and the needle drive. The patterns which are sewn are predominantly for reinforcing purposes and cover only a small surface area of the workpiece. The overall movement and the number of stitches required is, therefore, limited.
With reference to FIG. 1 the bar tacker sewing machine of the prior art is provided with a housing 1 mounted on a base 2. The housing 1 encloses a drive shaft, a cam shaft, a gear train connecting the drive and cam shafts as well as the needle bar drive linkages. Extending outward from base 2 under housing 1 is cylinder bed 3 which contains the feed mechanism for moving the workpiece clamp 4. The feed mechanism is linked to the two armed lever assembly 5.
In the prior art machine the principal motions for the complete bar tack operation are derived from two cams, which are mounted on either side of the housing on a transverse cam shaft geared to the needle drive shaft. The feed movement is along the axis X and Y as shown in FIG. 1 and this motion originates in the feed or style cam 7. The cam 7 has inside and outside tracks 8 and 9 of which track 8 controls lengthwise motion Y and track 9 controls transverse motion X through vertical two armed levers 10 and 11 respectively.
In order to insure continuous engagement between thread and needle, style cam 7 is also provided with means to actuate a nipper lever 6 which in turn operates a nipper which holds the thread tightly against the needle bar, and prevents thread pullout during start up and thread cutting. The knife cam of the prior art (not shown in FIG. 1) is located on the cam shaft on the opposite side of housing 1 from style cam 7 and provides the timing and movement for two functions, namely thread cutting and workpiece release.
The prior art machine is controlled by two foot actuated treadles mechanically connected to the sewing machine. One treadle starts and stops machine operation while the second treadle operates the thread cutting stroke and sequentially the workpiece release motion. All other movements are provided by either the style cam or the knife cam both of which rotate in timed relation with needle reciprocation.
The work clamp of the prior art consists of bottom clamp element 12 which is attached to support arm 13. Upper clamp elements 14 and 15 are mounted on support arm 13 for vertical sliding movement away from bottom element 12. Springs 16 and 17 are fixed to support arm 13 and engage the upper clamp elements 14 and 15 respectively to urge said elements downward into firm engagement with bottom clamp element 12. In order to overcome the clamping force of springs 16 and 17 and release a workpiece held thereby, a lever 18 is provided which engages the protruding ends of the springs 16 and 17. The lever 18 is lifted vertically by the action of a knife actuating lever (not shown) which in turn is actuated by a knife cam. This system requires that the clamp be released with each cutting stroke of the knife. In addition, it can be seen that it would be difficult to operate the dual upper clamp elements 14 and 15 individually.
THE PREFERRED EMBODIMENT
The automatically controlled bar tacker sewing machine associated with this invention employs the standard mechanism and is best shown in FIG. 2. In order to provide motion for the work clamp 20, the operation levers 25 and 26 are connected through linkage 23 to the clamp 20 and have gear sectors 32 and 33 fixed to the upper end of the lever arms. The gear sectors 32 and 33 mesh with pattern drive gears 34 and 35. The gears 34 and 35 are driven by stepping motors 36 and 37 as shown in FIG. 2. Each of the stepping motors is constructed to respond with a specific degree of rotary motion for each drive pulse it receives. As shown in FIG. 7, in order to generate the drive signal, a digital control 38 is provided which may be programmed to generate the pulses necessary to cause movement of the workpiece through a predetermined tack pattern. The programmed instruction may be in the form of a PROM (Programmable Read Only Memory) which may be inserted into circuitry of control 38 to cause generation of the pulses necessary for the desired pattern. To obtain different patterns, all that is needed is to change to a different PROM. A bar tacking sewing machine of this type is described in U.S. Pat. application Serial No. 530,048.
The work clamp assembly 20 of this invention is shown in FIG. 2 in association with an automatically controlled bar tacking sewing machine as described above. As best shown in FIG. 3, the assembly 20 consists of a lower clamping element 21, a support arm 22 fixed to lower element 21 and an upper clamping element 24. The upper clamping element 24 is slidably mounted on arm 22 for vertical movement into clamping position. Spring bars 27 are fixed to support arm 22 and engage upper clamp element 24 to resiliently bias this element downward into engagement with the lower clamping element 21.
Lower clamping element 21 is an assembly of carrying arm 28 and feed plate 29. The feed plate 29 being connected to carrying arm 28 by means of a quick disconnect fitting 30. The composite element 21 forms the base for the clamp assembly 20 and is attached to the sewing machine for movement in the x and y coordinates shown in FIG. 1. The support arm 22 is fixed to the carrying arm 28.
The upper clamping element 24 consists of a pair of mated clamp feet 39 and 40 which are each separately mounted on slides 41 and 42. The slides 41 and 42 are in turn mounted for vertical sliding motion in grooves 43 and 44 and are held in place by plate 45. Each of the clamping elements is constructed with a window to allow access to the workpiece. The shape of this window must be varied depending upon the pattern to be sewn. In order to facilitate removal of the feet 39 and 40 to change the size or shape of the window, they are secured to the slides 41 and 42 by means of quick disconnect fittings 46. The fittings 46 may consist of screw 47, split collar 48 and wedge collars 49 and 50. In this manner the feet 39 and 40 may be removed quickly without complete removal of the screw 47.
In order to force the clamp feet 39 and 40 into engagement with the feed plate 29, spring bars 27 are mounted on either side of arm 22 and are connected to slides 41 and 42 through slots 31. The biasing force of spring 27 is set downward and may be adjusted by tension bolts 51.
The unclamping force is supplied by pneumatic piston and cylinder assemblies 52 which are mounted on support arm 22 through bracket 53. The pistons of the assembly 52 are connected to bell crank levers 54 by pins 60. The bell crank levers are pivotally mounted on both sides of the support arm 22 through pivot brackets 55 and pins 56. Cams 61 are mounted on one end of the bell crank levers 54 by adjustment bolts 62 and engage the spring bars 27 to move the spring bars 27 and, therefore, the slides 41 and 42 upward upon actuation of piston and cylinder assemblies 52. This action will release the workpiece from the clamp.
As shown in FIG. 7, the pressure source 57 to the piston and cylinder assemblies 52 is controlled by electrical valve switch 58 which may be actuated by a signal from automatic control system 38 or manually through treadle 59. In this manner selective independent release of the clamp assembly feet 39 and 40 can be achieved without dependence on any other function of the sewing machine. This will result in a faster, more flexible and accurate sewing operation. It is observed that piston and cylinder assemblies 52 could be replaced by electric solenoids without detracting from the operation of the invention. | This invention relates to a device for selectively actuating the workpiece clamp of an automatically controlled bar tacker sewing machine utilizing electrically operated pneumatic cylinders operatively connected to the upper clamping element to cause release of the workpiece. The clamp feet are releasably independent of other sewing operations. The upper clamping plate and the feed plate are secured to the clamp assembly by quick change fittings. | 3 |
CROSS-REFERENCE TO RELATED APPLICATION
This application claims the benefit of U.S. Provisional Patent Application Ser. No. 60/789,975, filed Apr. 6, 2006, the entire disclosure of which is hereby incorporated by reference.
BACKGROUND
1. Technical Field
The present invention relates generally to the field of anesthesiology and to patient ventilating and anesthetizing and, more particularly, to a combination laryngeal mask airway with dual blocking and fluid removal features and method to ventilate a patient while isolating the trachea and the esophagus from each other.
2. Description of the Related Art
Airway devices are widely used in hospital surgical environments to provide respiratory assistance and to ventilate patents during medical procedures. Reference to ventilating includes providing breathable air or oxygen, for example, and removing gas, etc., e.g., exhalant exhaled by a patient, and providing anesthesia and/or other materials to and/or from the lungs of a patient. Ventilating also has the usual meaning as used in the field of medicine. The various gases, e.g., oxygen, air, anesthesia, etc., alone or in combination sometimes are referred to below collectively as gas mix.
While there are a multitude of airway devices currently on the market, one popular airway device is an endotracheal tube and another is a laryngeal mask airway (sometimes referred to in abbreviation as LMA). While the use of these devices is widespread, there are disadvantages associated with each of these devices.
As one example, endotracheal tubes are used to ventilate patients requiring anesthesia and/or respiratory assistance. An example of a conventional endotracheal tube is a plastic tube, which is inserted into a patient's mouth, is passed down the trachea through the vocal cords and is lodged in the trachea proximal (or above) to the lungs. The endotracheal tube may have a cuff or balloon portion surrounding the circumference of the endotracheal tube near the distal end that rests in the patient's trachea. After the endotracheal tube has been inserted properly, the cuff may be inflated to seal against walls of the trachea. Once sealed, positive pressure ventilation may be used to provide respiratory assistance and, if desired, anesthesia or other gas, gas mix, etc., to the patient though the endotracheal tube via a ventilator. The cuff provides a seal that tends to block liquids and solids from passing along the outside of the endotracheal tube between the tube and trachea walls and entering the patient's lungs.
While endotracheal tubes are ubiquitous in modern medicine, there are problems associated with the insertion of endotracheal tubes in patients. For example, there may be difficulty inserting the endotracheal tube into the proper position within the patient's trachea. A physician inserting the endotracheal tube may have difficulty viewing the trachea and there exists a possibility of inserting the endotracheal tube into the patient's esophagus, which leads to the patient's stomach rather than to the patient's lungs. If the tube is misdirected to the stomach, the lungs may not receive the proper air/oxygen mix. Additionally, the stomach may become filled with air possibly causing the patient to regurgitate, and the regurgitated material from the stomach may back flow and get into the patient's lungs. Another disadvantage of using an endotracheal tube is the invasive nature of intubation.
A laryngeal mask airway (LMA) overcomes many disadvantages associated with endotracheal tubes. An example of an LMA is disclosed in U.S. Pat. No. 6,634,354, issued Oct. 21, 2003 to Christopher, which is incorporated in its entirety by this reference. That LMA includes a hollow tube (sometimes referred to as a tubular guide, tube or guide) and a laryngeal mask. The laryngeal mask of the LMA is intended to fit in the mouth of a patient and to cover the two openings leading, respectively, to the esophagus and to the trachea, on the one hand, blocking the fluid path to and from the esophagus and stomach and, on the other hand, providing a fluid path to the trachea and lungs for ventilating the patient. The laryngeal mask may be positioned without requiring the physician to view the airway directly. The laryngeal mask has an inflatable cuff or rim area. Once the laryngeal mask is placed into the patient's mouth, the cuff can be inflated to seal against the walls of the inside of the mouth and, if positioned properly, to block flow to and from the esophagus. A rubber, plastic or like flexible, somewhat membranous support material extends from the cuff to form a recessed area, e.g., a space or volume, into which gas mix can be pumped through the tube or other instrumentality of the LMA to provide the requisite air and/or anesthesia to the patient. The tube is of relatively large diameter, as compared to the usually relatively narrower diameter passage of a conventional endotracheal tube, and such relatively large diameter facilitates gas mix and exhalant flow with relatively minimal interference, pressure drop, etc. The support material supports the cuff from the tube. Thus, the LMA can be used to supply gas mix to the recessed area and from there to the trachea. An advantage of an LMA is that the patient ordinarily does not have to be intubated with an endotracheal tube. If the LMA is not fully blocking flow to and from the esophagus, the gas mix primarily will flow to the lungs via the trachea because the trachea-lungs flow path generally has less resistance than the flow path from the esophagus to the stomach, and provided the pressure is not too great, the vast majority of the gas mix will flow into the lungs, and the stomach will not fill with the gas mix.
A drawback with the LMA is that the device cannot be used on all patients. For example, the device cannot be used on patients that are at risk for vomiting because if the laryngeal mask is not in the proper position, it does not fully isolate the airway to the trachea from the passageway to the esophagus. Thus, if the patient vomits during a medical procedure in which the LMA is used, the expelled fluid or solids could potentially flow from the esophagus to the trachea and enter the patient's lungs. An LMA ordinarily would not be used for patients that have eaten in the six hours prior to surgery, pregnant women, and trauma victims.
Thus, there is a need in the art to address the above mentioned and possibly other deficiencies and inadequacies of the prior art.
SUMMARY OF THE INVENTION
The present invention relates to a laryngeal mask airway and method for isolating a patient's trachea and esophagus during a medical procedure in which a laryngeal mask is used to supply ventilation or respiratory assistance to the patient.
An aspect of the invention relates to a laryngeal mask airway wherein the esophagus may be intubated for isolation from the trachea, drainage maybe provided for fluids from the esophagus, and a relatively unimpeded or broad path is provided for air, anesthesia, etc. to the trachea of a patient.
One aspect of the present invention relates to a laryngeal mask airway device including: a tubular guide including a distal portion and a proximal portion; a laryngeal mask attached to the distal portion of the tubular guide, wherein the laryngeal mask includes a recessed proximal portion and a distal portion; a first passageway extending from the proximal portion of the tubular guide to the recessed proximal portion of the laryngeal mask; and a second passageway extending through a distal portion of the laryngeal mask.
Another aspect of the present invention relates to a laryngeal mask airway device including: a tubular guide including a distal portion and a proximal portion; a laryngeal mask attached to the distal portion of the tubular guide, wherein the laryngeal mask further includes a support member; a first passageway extending from the proximal portion of the tubular guide to a position within the laryngeal mask located above the support member; and a second passageway extending generally along the tubular guide and extending through a distal portion of the laryngeal mask.
Another aspect of the present invention relates to a method for using a laryngeal mask airway device, the method including: inserting a portion of a laryngeal mask airway device including a laryngeal mask and a portion of a tubular guide into an associated patient's mouth; inflating the laryngeal mask; supplying air to the patient after insertion of the laryngeal mask airway device; inserting a first instrumentality through a first passageway of the laryngeal mask airway device into the patient's esophagus; inflating a cuff associated with the first instrumentality to effectively block the patient's esophagus; and providing a gas to the associated patient through a second passageway of the laryngeal mask airway device into the patient's trachea.
Another aspect of the present invention relates to a method for using a laryngeal mask airway device, the method including: inserting a portion of a laryngeal mask airway device including a laryngeal mask and a portion of a tubular guide into an associated patient's mouth; inflating the laryngeal mask; supplying air to the patient after insertion of the laryngeal mask airway device; inserting a first instrumentality through a first passageway of the laryngeal mask airway device into the patient's trachea; inflating a cuff associated with the first instrumentality to effectively seal the patient's trachea; providing a gas to the patient through the first instrumentality; inserting a second instrumentality through a second passageway of the laryngeal mask into the laryngeal mask; and removing at least one of fluids or particles released from the patient's stomach into the laryngeal mask through the second instrumentality.
These and other systems, methods, features, and advantages of the present invention will be or become apparent to one with ordinary skill in the art upon examination of the following drawings and detailed description. It is intended that all such additional systems, methods, features, and advantages be included within this description, be within the scope of the present invention, and be protected by the accompanying claims.
In the description and drawings, particular embodiments of the invention have been disclosed in detail as being indicative of some of the ways in which the principles of the invention may be employed, but it is understood that the invention is not limited correspondingly in scope. Rather, the invention includes all changes, modifications and equivalents coming within the spirit and terms of the claims appended hereto.
Features that are described and/or illustrated with respect to one embodiment may be used in the same way or in a similar way in one or more other embodiments and/or in combination with or instead of the features of the other embodiments.
It should be emphasized that the term “comprise/comprising” when used in this specification is taken to specify the presence of stated features, integers, steps or components but does not preclude the presence or addition of one or more other features, integers, steps, components or groups thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
Many aspects of the invention can be better understood with reference to the following drawings. The components in the drawings are not necessarily to scale, emphasis instead being placed upon clearly illustrating the principles of the present invention. Likewise, elements and features depicted in one drawing may be combined with elements and features depicted in additional drawings. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views, and primed reference numerals represent parts that are similar to those parts designated by the same unprimed reference numeral.
FIG. 1A is a front perspective view of an exemplary prior art laryngeal mask airway;
FIG. 1B is a cross-sectional view of the distal portion of the exemplary laryngeal mask airway of FIG. 1A ;
FIG. 2 is a cross-sectional view of the exemplary prior art laryngeal mask airway of FIGS. 1A and 1B and the patient's airway after the laryngeal mask has been inserted and inflated;
FIG. 3A is a side elevation view partly in section and perspective of a laryngeal mask airway in accordance with an embodiment of the present invention with the laryngeal mask inflated and a passageway extending through part of the laryngeal mask for placement and holding of an endotracheal tube or the like;
FIG. 3B is a top plan view partly in section of the distal portion of the laryngeal mask airway of FIG. 3A .
FIG. 3C is an enlarged side elevation view partly in section of part of the laryngeal mask and passageway shown in FIGS. 3A and 3B ;
FIGS. 4A and 4 b are schematic side elevation views showing respective embodiments of laryngeal mask airways as embodiments of the invention in use in the oral cavity of a patient;
FIGS. 5A and 5B are front and rear perspective views of a laryngeal mask airway in accordance with an embodiment of the present invention including a passageway extending outside and held to the tube of the laryngeal mask;
FIGS. 6A and 6B are front and rear perspective views of a laryngeal mask airway in accordance with an embodiment of the present invention including a passageway extending through a support portion of the laryngeal mask;
FIGS. 7A-7C are schematic front views of the laryngeal mask in accordance with respective embodiments of the present invention with the passageway through the inflatable member, outside the laryngeal mask, and through the support member, respectively;
FIG. 8 is a cross-sectional view of a laryngeal mask airway in accordance with an embodiment of the present invention in a patient's airway after the laryngeal mask has been positioned and the endotracheal tube has been inserted in the esophagus;
FIGS. 9 and 10 are schematic side elevation views showing a laryngeal mask airway in various orientations in the oral cavity of a patient.
BRIEF DESCRIPTION OF PRIOR ART
FIGS. 1 A, 1 B, and 2
The following description is exemplary in nature and is not way intended to limit the scope of the invention as defined by the claims appended hereto. An exemplary laryngeal mask is described in U.S. Pat. No. 6,634,354 to Christopher, which is incorporated by reference as if fully rewritten herein.
In FIGS. 1A. 1B and 2 of the drawings, for example, a patient 1 is shown schematically with the mouth 2 in cross section and open and leading to the back of the throat 3 (sometimes the mouth and/or throat are referred to as the oral cavity of the patient) and from there (i) to the trachea 4 via the laryngeal inlet 5 , which provides an airway 6 that leads to the lungs, and (ii) to the esophagus 7 , which leads to the stomach; and exemplary laryngeal mask airway (LMA) 10 of the type generally described in the Christopher patent is in the patient. The LMA 10 includes a tubular guide 12 , e.g., a hollow tube, sometimes referred to below as a tube or guide, and a laryngeal mask 14 surrounding the distal end 12 d of the tubular guide 12 . When in use, the proximal end 16 of the tubular guide 12 remains outside of the patient's mouth and, therefore, is accessible to the healthcare provider, e.g., physician, nurse or other individual. The proximal end 16 of the tubular guide 12 may be conveniently of size and shape to secure a variety of attachments to the tubular guide 12 (e.g., a syringe, an endoscope probe, an endotracheal tube, a gas mix supply connection to receive a gas mix for ventilating, anesthetizing, etc., a patient, a drainage tube, etc.). The laryngeal mask airway 10 further includes an inflation tube 18 and an air valve 20 for inflating and deflating an inflatable member 22 , e.g., a cuff, of the laryngeal mask 14 . In addition, the laryngeal mask airway 10 , includes a central support member 24 , e.g., a flexible and possibly somewhat elastic or yielding membranous material, as was mentioned above, which generally provides support for the laryngeal mask 14 including the cuff 22 and support member 24 from the tube 12 .
Typically, the size and shape of the tubular guide 12 are selected so that the distal portion 12 d can be readily inserted into a patient's mouth and upper airway with the laryngeal mask 14 substantially sealing the laryngeal inlet 5 of the patient 1 . The tubular guide 12 is generally a J-shape to follow the profile of a typical patient's airway through the mouth, over the tongue, and into the laryngopharynx region of the patient just above the opening 5 a to the larynx. The guide 12 is shaped to prevent the patient's tongue and collapsible pharynx from obstructing access to the trachea. The guide 12 further defines a passageway or channel 12 a for ventilating a patient, e.g., to direct relatively unimpeded flow of gas mix to the lungs and exhalant from the lungs. The size of the passageway 12 a may be suitable for possible later insertion of a tube or other suitable instrumentality. (e.g., endotracheal tube, endoscope, drainage tube, etc.) while still providing space for ventilating the patient. Placing additional tubes or other instrumentalities in the passageway 12 a of the tubular guide 12 , though, may impede flow for ventilating purpose.
The guide 12 may be made, for example, of plastic with sufficient strength and rigidity to keep the patient's teeth apart and to prevent the patient from biting down and collapsing the guide 12 . The guide 12 may be made of other suitable material. The guide 12 is sized to accommodate a wide range of patient sizes and conditions. The distal opening 12 e of the guide 12 is beveled to substantially match the angle of the patient's laryngeal inlet after insertion of the laryngeal mask airway 10 into the patient's airway.
Referring to FIG. 1B , a top view of the laryngeal mask 14 of the LMA 10 is illustrated. The laryngeal mask 14 includes an upper portion 26 , a lower portion 28 and the central support member 24 . The central support member 24 extends outward from the guide 12 to the inflatable member 22 (cuff). The laryngeal mask 14 may be made, for example, of a soft, flexible material (e.g., a polymer or rubber) to enable the laryngeal mask 14 to be advanced into position without injury to the patient and to create, when the cuff is inflated, a substantially air-tight seal about the patient's laryngeal inlet, as is shown in FIG. 2 . The degree of inflation of the laryngeal mask 14 member 22 can be adjusted via the inflation tube 18 and air valve 20 .
In the ideal use, the laryngeal mask 14 and its support member 22 are positioned in the patient so that the lower portion 28 of the laryngeal mask 14 substantially blocks the esophagus 7 to minimize the risk of regurgitation of stomach contents and the passage of air into the stomach. The upper portion 26 of the laryngeal mask 14 guides the distal end 12 d of the guide 12 into alignment using the laryngeal inlet 5 of the patient 1 as a guide to insert along the patient's airway, which is partially represented by the arrow 6 .
As is shown in FIGS. 1A and 2 , the laryngeal mask 14 may be boot-shape when inflated. The lower portion 28 of the laryngeal mask 14 forms the toe of the boot, which is designed to block the esophagus. The lower portion 28 of the laryngeal mask 14 also helps to align the distal opening 12 e of the guide 12 with the patient's laryngeal inlet 5 . Once inserted, the inflatable member 22 (cuff) of the laryngeal mask 14 is inflated through the inflation tube 18 so that the upper portion 26 of the laryngeal mask 14 substantially fills the patient's laryngopharynx 5 b at the level of the laryngeal inlet 5 , as is shown in FIG. 2 . The upper portion 26 of the laryngeal mask 14 surrounds the laryngeal inlet 5 so that the distal opening 12 e of the guide 12 is substantially sealed in fluid communication with the laryngeal inlet, e.g., pressing against walls of the oral cavity portions of the patient. Thus, substantially all of the gas inhaled or exhaled by the patient is intended to pass through the guide 12 .
While the conventional laryngeal mask 14 of the LMA 10 is designed to substantially block the esophagus and to minimize the risk of regurgitation of stomach contents into the patient's lungs, the laryngeal mask 14 may not completely isolate the esophagus from the trachea, especially if the LMA 10 is not properly positioned in the patient, and the problems discussed above limit the number and types of procedures in which the conventional laryngeal airway 10 may be used.
DESCRIPTION OF THE INVENTION
Referring to FIGS. 3-9 , a laryngeal mask airway 50 (LMA) in accordance with embodiments of the present invention is illustrated. The LMA 50 includes two fluid conducting portions 51 and 52 , which may be cooperative as is described below and which also may provide independent flow paths, passageways or the like, as also is described below. In a sense the two fluid conducting portions 51 , 52 of the LMA 50 complement each other; the portion 51 is similar to the LMA 10 (described above) and the portion 52 is similar to an endotracheal tube. The portion 52 may be an endotracheal tube 53 a , as is shown in FIG. 4A . Alternatively, the portion 52 may be a tube or sleeve 53 b through which an endotracheal tube 53 a may be inserted, e.g., as is illustrated in FIG. 4B , the sleeve facilitating such insertion. It will be appreciated that some other instrumentality may be the same as or similar to tubes 53 a , 53 b in form and function.
As is illustrated schematically in FIGS. 4A and 4B , in using the LMA 50 it is preferred that the endotracheal tube portion 52 would have its distal end 52 d inserted into the esophagus 7 of a patient 1 ; and it is preferred that the fluid conducting portion 51 would fit the patient such that the distal end 28 of the laryngeal mask 14 thereof would block fluid to and from the esophagus 7 of the patient. At least in part, the complementary relation of the portions 51 , 52 , as is described below, in a sense is as respective backups or supplements for each other. For example, the endotracheal tube 53 a can be positioned in the esophagus to block fluid flow to and from the esophagus except for flow through the tube 53 a ; and the laryngeal mask 14 of the portion 51 could be positioned also to block fluid flow to and from the esophagus, e.g., generally as is illustrated in FIGS. 2 , 4 A and 4 B. In such case ventilating of the patient can be carried out via the relatively large tube 12 of the portion 51 and laryngeal mask 14 and, if necessary, fluid or other waste can be withdrawn from the stomach and esophagus via the endotracheal tube 53 a . Positioning of the endotracheal tube in expanded relation of its sealing balloon 54 in the esophagus and the further positioning of a portion of the laryngeal mask 14 in the entrance to the esophagus provide added protection against fluid or other waste from the esophagus and stomach from reaching the trachea and lungs. Also, such use of the parts of the LMA 50 avoids the need for intubation of the patient, i.e., inserting of the endotracheal tube 53 a into the trachea.
Turning to FIGS. 3A , 3 B, 3 C, 4 A and 4 B, the LMA 50 includes the first fluid conducting portion 51 , which includes a tube 12 and a laryngeal mask 14 . The LMA 50 also includes the second fluid conducting portion 52 , which includes an elongate hollow endotracheal tube 53 a that has an expandable sealing balloon 54 at the distal end 53 d , e.g., as are similar to a conventional endotracheal tube, for example. As is shown in FIG. 4B , the fluid conducting portion 52 includes a tube 53 b , and the endotracheal tube 53 a is inserted in the through tube 53 b . The tube 53 b is adequately long to extend beyond the laryngeal mask 14 toward the esophagus when in place in a patient and to extend out through the patient's mouth for easy access to insert the tube 53 a or some other device therein to extend down to the patient's esophagus.
The endotracheal tube 53 a and tube 53 b may be made of plastic or of such other materials as endotracheal tubes typically are made or of some other suitable material. An inflation line 55 and air valve 56 may be used to expand the sealing balloon 54 to provide a seal with the wall of the esophagus 7 to prevent fluid flow along the outside of the tube 53 a , although fluid may flow through the tube 53 a . Applying air or other fluid to the sealing balloon 54 via the inflation line 55 and valve 56 after the endotracheal tube 52 has been inserted into the patient expands the balloon to form a seal; allowing that fluid to be withdrawn through the inflation line and air valve 56 allows the sealing balloon 54 to collapse to allow for relatively easy withdrawal of the endotracheal tube 52 . Alternatively, the sealing balloon 54 may be another type of seal that does not require selective inflating and deflating, e.g., a resilient, deformable sealing balloon or other device that is suitably large to provide sealing function and still is sufficiently flexible and/or deformable to allow it to be inserted and withdrawn from the patient, e.g., esophagus.
The laryngeal mask 14 has a guide hole opening 57 through it to allow a portion 58 of the endotracheal tube 53 a to extend therethrough. The guide hole opening 57 is so located in the laryngeal mask 14 as to position to the endotracheal tube 53 a in position relative to the laryngeal mask such that the distal end 53 d of the tube 53 a would tend relatively easily to be guided for insertion into the esophagus 7 of a patient when the LMA 50 is properly inserted through the oral cavity (mouth) of the patient.
The opening 57 may be formed in a reinforced material portion of the inflatable member (cuff) 22 of the laryngeal mask 14 or the central support member 24 thereof. The opening 57 may be formed in a small tube-like member 57 a that is mounted in the inflatable member 22 and/or in the central support member 24 . The tube 53 a may slide freely in the opening 57 or it may be fixed in that opening. In an exemplary embodiment, the tube 53 a may slide relatively freely in the opening 57 when the inflatable member 22 of the laryngeal mask is uninflated, thereby to facilitate placing the distal end 53 d of the tube 53 a and the sealing balloon 54 in the esophagus 4 . However, with the inflatable member 22 being inflated, it may tend to expand so as to cause the material at the opening 57 to engage the tube 53 a relatively securely to retain it in position relative to the laryngeal mask 14 . The inflatable member 22 may be inflated after it has been positioned in the oral cavity 3 of the patient so that the inflated walls of the inflatable member engage walls of the oral cavity to hold the laryngeal mask 14 in position in the oral cavity while also tending to hold the tube 53 a in position. Thus, the portions 51 , 52 of the LMA 50 would be held in relatively fixed position relative to the oral cavity and to the esophagus 7 and trachea 4 .
As is illustrated in FIG. 4B , the tube 53 b may be positioned relative to the fluid conducting portion 51 and the laryngeal mask 14 thereof in a manner similar to the manner described above for the endotracheal tube 53 a . In this case the endotracheal tube 53 a may be inserted through the tube 53 b to the illustrated location in the esophagus to provide the functions described herein for the endotracheal tube.
Briefly referring to FIGS. 5A and 5B , another embodiment of LMA 50 ′ is illustrated. The parts of the LMA 50 ′ are similar to those described above with respect to FIGS. 3A , 3 B, 3 C, 4 A and 4 B, except that the endotracheal tube 53 a of the fluid conducting portion 52 is attached to the exterior of the fluid conducting portion 51 . As is seen in the drawings, the portion of the tube 53 a that is parallel to and substantially coextensive with the tube 12 is attached, e.g., by adhesive material or by some other fastening mechanism, such as, for example, a band 12 b , or a clamp, rivet or other device (not shown), to the exterior surface 12 f of the tube 12 . In the area where the tube 53 a passes adjacent the inflatable member 22 and support portion 24 of the laryngeal mask 14 rather than through either one of them, the tube 53 a may be attached to the laryngeal mask material or may have sufficient rigidity to follow the J-shape configuration of the tube 12 just upstream of and at the area of the laryngeal mask. In FIGS. 5A and 5B the endotracheal tube 53 a does not have a separate inflation line for the sealing balloon 54 ; rather the sealing balloon may be somewhat normally expanded and adequately flexible to slide into position in the esophagus (or in the trachea) of a patient while making sealing engagement with the adjacent wall of the esophagus or trachea.
In FIGS. 6A and 6B , which are similar to FIGS. 4A and 4B , another LMA 50 ′ is shown. An opening 57 b is in the support portion 24 rather than in the inflatable member 22 ; and the tube 53 a passes through such opening 57 b . Although not shown in the drawing, if desired suitable reinforcement material, e.g., a separate tube section or thickened material that forms the support portion 24 , may be provided at the area of the opening 57 a to provide a suitable seal with the tube 53 a and to avoid tearing of the support portion material on account of movement of the tube 53 a relative to the support member.
FIGS. 7A , 7 B and 7 C are schematic front plan views looking onto the laryngeal mask 14 to show exemplary locations at which the tube 53 a extends outward therefrom, respectively, through the inflatable member 22 ( FIG. 6A ), outside the laryngeal mask and beneath (as illustrated) the inflatable member ( FIG. 6B ), and through the support member 24 ( FIG. 6C ).
The tubes 53 a , 53 b (sometimes referred to as passageways) may pass through the laryngeal mask 14 without interfering with the inflation or deflation of the laryngeal mask. One of ordinary skill in the art will readily appreciate that the tubes 53 a , 53 b may be secured above or below the central support member 12 and further that the tubes 53 a , 53 b may exit above or below the central support member 12 . The location of the distal opening 60 , 61 of the tubes 53 a , 53 b is positioned to provide a convenient pathway to the patient's esophagus.
The tube 53 b may be made of a similar material as the tube 53 a (e.g., plastic with sufficient strength and rigidity to keep the patient's teeth apart and prevent the patient from biting down and altering or damaging the tube). The tube 53 b may also be made of a material more compliant or elastic than the material that the tube 12 is made (e.g., rubber, relatively soft or flexible plastic, etc.) so that the material will not interfere with insertion of the laryngeal mask airway 50 .
Referring to FIG. 8 as well as to the other drawing figures, methods for using the laryngeal mask airway 50 of embodiments of the present invention will now be described. The curved distal portion of the tubular guide 12 is first inserted into the patient's mouth and laryngopharynx with the laryngeal mask 14 deflated. After the distal portion of the tubular guide 12 and the laryngeal mask 14 are appropriately positioned relative to the patient's laryngeal inlet 5 , the laryngeal mask 14 is inflated via the inflation tube 18 and the air valve 20 to establish a seal around the patient's laryngeal inlet, as illustrated in FIG. 8 . The lower portion 28 of the inflated laryngeal mask 14 substantially blocks the patient's esophagus. The upper portion 26 of the inflated laryngeal mask 14 substantially fills the patient's laryngopharynx adjacent to the laryngeal inlet 5 . The laryngeal mask 14 thereby seals the distal opening of the tubular guide 12 in fluid communication with the patient's laryngeal inlet. The side portions of the laryngeal mask may pinch the sides of the patient's epiglottis, which also tends to lift the epiglottis from the laryngeal inlet, thereby clearing an airway to the patient's trachea 4 . After the laryngeal mask 14 is properly positioned and inflated in the mouth of the patient, an instrumentality (e.g., an endotracheal tube 53 a , an endoscope, a drainage tube, etc.) can be inserted into the esophagus 7 through passageway (tube) 53 b ( FIG. 4B , for example).
Alternatively, the tube 53 b may be inserted through the guide hole 57 after the laryngeal mask 14 is in place in a patient; and thereafter another instrumentality can be inserted into the esophagus 7 through tube 53 b.
As another alternative, the instrumentality, e.g., an endotracheal tube 53 a , may be inserted through the guide hole after the laryngeal mask 14 has been placed in the patient; this may be difficult if the inflatable member 22 already has been inflated, but if it is not inflated it may be difficult to insert the instrumentality through the guide hole 57 due to the inflatable member 22 being somewhat flaccid.
Even another alternative is to have the instrumentality, e.g., endotracheal tube 53 a , in position in the guide hole and extending generally in the manner illustrated in FIG. 8 and the other figures hereof, prior to placing the laryngeal mask 14 in the patient; and in this case the placing of the laryngeal mask 14 in the patient also would include guiding the distal end of such endotracheal tube 53 a (or other instrumentality that is positioned by the guide hole 57 ) to the esophagus 7 . The inflatable member 22 may be inflated after positioning the laryngeal mask 14 properly in the patient as described above.
After the instrumentality, e.g., endotracheal tube 53 a , has been inserted into the esophagus a suitable distance, e.g., approximately three to four inches, so as to place the sealing balloon or cuff 54 in relation to the esophagus so that it can form a seal therewith, the sealing balloon is inflated via inflation tube 55 and air valve 56 from a suitable inflation source, e.g., an air pump or source of compressed air. In the present example, the cuff 54 is shaped to conform to the contours of the patient's esophagus.
Upon inflation of the sealing balloon or cuff 54 , the patient's esophagus 7 is isolated from the inlet 5 to the trachea 4 . The physician may then use the hollow tubular guide 12 and/or another instrumentality (e.g., an endotracheal tube, an endoscope, a drainage tube, etc.) (not shown) to provide air/oxygen to the patient via a ventilator/respirator (not shown) or perform other desired functions with the instrumentality.
By inserting the instrumentality 53 a , for example, through the tube or passageway 53 b and into the esophagus 7 and inflating the sealing balloon or cuff 54 , any fluid regurgitated from the stomach may flow up through the instrumentality 53 a and be removed outside the mouth of the patient through the instrumentality 53 a . Therefore, any regurgitated material and/or fluid may be prevented from entering the lungs of the patient. Thus, the isolation of the stomach and esophagus is accomplished by both the instrumentality 53 a and cuff 54 and by the inflated laryngeal mask 14 , both of which block flow from the esophagus to the trachea. Meanwhile the patient may be ventilated via the tubular guide 12 without any interference with the passageway leading to the trachea for respiration and/or ventilation assistance.
Alternatively, as is illustrated schematically in FIGS. 9 and 10 if instrumentality 53 a , e.g., endotracheal tube, were inserted through the tube 53 b into the trachea (instead of the esophagus), the cuff 54 may be inflated within the patient's trachea to block the flow of fluids and particulates into the lungs. An air and/or anesthesia mix can be directed through the instrumentality 53 a to the lungs in this instance. As shown in FIG. 9 the laryngeal mask 14 may be positioned so that it does not seal the trachea 4 from the esophagus 7 , but it is open to at least the esophagus to provide a path to the passageway 12 a of the tubular guide 12 . If the patient were to regurgitate, the fluid and particulates could be removed via the recessed area in the support portion 24 of the laryngeal mask 14 and withdrawn through the tubular guide 12 or another instrumentality that is in the tubular guide, e.g. a drainage tube in this particular instance. The proximal end of the drainage tube may in such case be connected to a suction device (not shown) to remove any undesirable fluids and particulates. As shown in FIG. 10 the laryngeal mask 14 may be positioned to block the trachea 4 but not the esophagus 7 , while the instrumentality 53 a , e.g., endotracheal tube, and cuff 54 are in the trachea. In such case the laryngeal mask 14 still may have part exposed to the esophagus 7 to provide a fluid path for regurgitant or the like to be suctioned out via the passageway 12 a of tubular guide 12 or if need another suction tube may be inserted to remove regurgitant, etc.
By effectively isolating the patient's esophagus from the trachea, the laryngeal mask airway 50 overcomes many drawbacks of the conventional laryngeal mask airway and may be used in many situations to provide a patient with an air/anesthesia mix and avoids the possibility of regurgitation or other material from entering the patient's lungs.
It should be appreciated that the above described device and method provides for a laryngeal mask that can be used in many more instances than a conventional laryngeal mask. Although the invention has been shown and described with respect to certain preferred embodiments, it is obvious that equivalents and modifications will occur to others skilled in the art upon the reading and understanding of the specification. The present invention includes all such equivalents and modifications, and is limited only by the scope of the following claims. | The present invention relates generally to the field of laryngeal mask airway devices. The invention provides for dual passageways in a laryngeal mask which permits a physician to effectively isolate the trachea from the esophagus. In one embodiment, the physician separately inserts an instrumentality (e.g., an endotracheal tube) into a patient's esophagus in order to isolate the stomach from the lungs, respectively. In another embodiment, the physician inserts an instrumentality (e.g., an endotracheal tube) into the trachea and inserts another instrumentality (e.g., a drainage tube) in the second passageway within the laryngeal mask in order to remove particles or fluids contained in the laryngeal mask that may cause problems if allowed to flow through the patient's trachea to the lungs. | 0 |
BACKGROUND OF THE INVENTION
The present invention relates to automatic clothes washing machines and more particularly to an improved structure in such machines for effecting the washing of relatively small loads of clothing and especially heavily soiled clothing in a high detergent concentration.
Automatic clothes washing machines customarily provide, in a clothes basket adapted to hold several pounds of clothes, a sequence of operations in order to wash, rinse and extract water from the clothes in the basket. The sequence ordinarily includes a water fill followed by a washing operation which, in a vertical axis type machine, is provided by an agitator movably arranged to oscillate within the basket; a first centrifugal extraction operation in which the wash water is removed from the clothes by spinning the basket; another water fill followed by a rinsing operation in which the clothes are rinsed in clean water while the agitator is oscillated; and a final centrifugal liquid extraction operation in which the basket is spun to remove rinse water from the clothes. Machines having this type of cycle, or a variation thereof, generally produce highly satisfactory results in that the clothes come out properly cleaned and with a substantial part of the liquid removed.
In the case where clothes are extremely dirty or soiled with difficult to remove spots, they will emerge from the cycle of operations with at least some of those spots still visible. Generally, these exceptionally dirty clothes are a minority relative to a full wash. Thus, it would not be economical to add extra detergent to the full load of clothes just for the sake of cleaning an isolated heavily soiled item.
These types of clothes should be washed by themselves so that special treatment may be given to each item. One disadvantage which presents itself when very small loads are washed in the basket of a washing machine is that the amount of water required for washing a few items may be comparable to the amount of water used for washing several pounds of clothing. This, of course, represents an inefficient use of water with a resulting high cost of water and energy in heating the water in consideration of the results being obtained. Also, there is a correlary that the greater the quantity of water used, the greater the quantity of detergent needed in order to effect a proper detergent concentration in the water. This is even more critical in the instance of heavily soiled clothes which would require greater amounts of detergent. Considerations such as these have quite often led the owners of domestic clothes washing machines to do the washing of heavily soiled clothes by hand despite the availability of the machine.
One solution to this problem is the use of a small basket placed on the agitator inside the larger regular wash clothes basket. The motion of the agitator carries with it the small basket and provides a motion of the liquid in the basket which causes a suitable type washing action. This type of washing machine is described in U.S. Pat. No. 3,014,358 and is assigned to the assignee of the present invention. In the use of a small wash basket as described in U.S. Pat. No. 3,014,358 the clothes within the small basket are subjected to the same operational cycles as when the machine is used with a "normal" operation. The disadvantage in such a clothes washing cycle is that the water is continuously recirculated through the small basket. Accordingly, while the smaller basket has a relatively small volume the water level in the smaller basket is maintained by circulating all of the water in the machine machine through the smaller basket during the washing operation. This causes the detergent that is placed in the small basket to be diluted into the recirculating water in the machine.
By the present invention means are provided whereby during the washing cycle of operation only a predetermined volume of the fill water is circulated into the smaller basket during a timed recirculation cycle prior to the wash cycle. This relatively small volume of water is retained therein during the entire washing cycle of operation. This ability to confine a limited water volume allows for the attainment of a very high detergent concentration with the usage of reasonable and acceptable amount of detergent. Following this initial wash in a high detergent concentration the machine reverts to its "normal" cycle of operation; wherein all of the fill water in the machine is recirculated through the small basket during the ensuing spin, rinse, and extraction cycles of operation.
SUMMARY OF THE INVENTION
By the present invention there is provided a vertical axis clothes washing machine comprising a liquid and clothes containing means including a relatively large substantially imperforate outer receptacle, and a relatively large perforated clothes receptacle positioned within the receptacle. A removably mounted agitator extendes upwardly into the clothes receptacle. A drive system is provided for rotating the clothes receptacle and the agitator at a relatively high speed, including means for effecting a washing motion of the agitator. A water inlet means provides fresh water to the liquid and clothes containing means. A control terminates the flow of water from the inlet means and a washing motion of the agitator is initiated. Positioned on the agitator and movable therewith is a relatively small substantially imperforate basket which has overflow openings adjacent the top thereof. A recirculation pump including a conduit connected between an inlet in the outer receptacle and an outlet positioned for supplying liquid to the small imperforate basket are arranged to pump liquid from the outer receptacle through the outlet means. The control means is settable to provide a relatively high predetermined level of liquid when the clothes are to be washed in the clothes receptacle and settable to a relatively low liquid level when the clothes are to be washed in the small imperforate basket. Further, the control means includes valve means in the conduit for allowing a predetermined amount of liquid to flow through the outlet means whereby clothes contained in the small imperforate basket are washed in the predetermined amount of liquid independently of liquid in the outer receptacle.
DESCRIPTION OF DRAWINGS
FIG. 1 is a front elevational view of a clothes washing machine incorporating the present invention, the view being partially broken away and partially in section to illustrate details;
FIG. 2 is a schematic diagram of an electrical control circuit suitable for use with the machine of FIG. 1; and
FIG. 3 is a schematic view of the cam surfaces used in the recirculation water control timer operated switches of FIG. 2.
DESCRIPTION OF THE INVENTION
Referring now to the drawings there is shown an agitator type clothes washing machine 10 having a conventional basket or clothes receiving receptacle 11 perforated over its side and bottom walls with perforations 12 and disposed within an outer imperforated tub 13. Tub 13 is mounted within an appearance cabinet 14 which includes a cover 15 hingedly mounted in the top portion 16 of the cabinet for providing access through an opening 18 to the basket 11. At the center of the basket 11 there is positioned a vertical axis agitator 20 which includes a center post 21 and a plurality of water circulating vanes joined at their lower ends by an outwardly flared skirt 22.
Both the clothes basket 11 and the agitator 20 are rotatably mounted. The basket 11 is mounted on a flange of a rotatable hub 24 and the agitator is mounted on a shaft 25 which extends upwardly through the hub and through the center post 21 and is secured to the agitator so as to drive it. During the cycle of operation of the machine the agitator 20 is first oscillated back and forth on its axis, that is, in a horizontal plane within the basket 11 to wash the clothes therein. Then after a predetermined period of this washing action the basket 11 is rotated at a high speed to extract centrifugally the washing liquid from the clothes and discharge it to drain as will be explained. Following this extraction operation a supply of clean water is introduced into the basket for rinsing the clothes and the agitator is again oscillated. Finally, the basket is once more rotated in high speed to extract the rinse water.
The basket 11 and agitator 20 may be driven by any suitable means as the drive means forms no part of the present invention. However, by way of example they are shown driven from a reversible motor 26. The motor 26 drives the basket 11 and the agitator 20 through a drive including a clutch 27 which is mounted on the motor shaft. The clutch 27 allows the motor 26 to start within a load and then to accept the load as it comes up to speed. A suitable belt 28 transmits power to a transmission assembly 30 through a pulley 31. Thus, depending upon direction of motor rotation the pulley 31 of the transmission is driven in opposite directions. Preferably, as will be more fully explained below, transmission clutch 27 is also a two-speed clutch. Specifically, in the illustrated machine the clutch 27 provides a direct drive between the motor 26 and the pulley 31 and a reduced speed drive to the pulley 31. The transmission 30 is so arranged that it supports and drives both the agitator drive shaft 25 and the basket mounting hub 24. When the motor 26 is rotated in one direction the transmission causes the agitator 20 to oscillate in a substantially horizontal plane within the basket 11. Conversely, when the motor 26 is driven in the opposite direction the transmission 30 rotates the wash basket 11 and agitator 20 together at high speed for centrifugal extraction. In order to introduce fresh water to the machine a suitable conduit 34 is provided having an outlet opening into the tub 13 so that suitable washing and rinsing liquid may be introduced in the desired quantities into the tub 13 and basket 11. It will at this point be noted that in the preferred construction shown the perforations 12 of the basket 11 cause the interior of the basket 11 to be in full communication with part of the tub 13 which is exterior to the basket 11 so that the liquid level in both the basket 11 and the tub 13 is the same. Thus, as the water rises in one it will also rinse in the other. With this type of structure suitable means may thus be provided in the tub 13 to determine when the appropriate water level in the basket 11 has been reached. In the present case this structure is provided in a conventional manner by means of a tube 36 which extends from an opening 37 adjacent the bottom of the tub 13 up to a pressure sensitive water level control 38 which may be of the conventional type.
In effect, in this type of water level control an electric switch is included in the device 38 and the switch is operated in response to an increase of the air pressure within the conduit 36. The increase in air pressure coming as a result of compression of air by a rise in the level of water in the tub 13. A further conventional embodiment of level control is the provision of means for varying the point at which the switch is closed by the air pressure so that any one of several different air pressures may be selected for the closing of the switch. In this manner different levels within the tub may be selected by movement of dial 39 to different positions. The water level content may be of the type wherein the water levels selected may be infinite or of the type wherein the selection is restricted to predetermined levels. In the present embodiment a 4-position control is employed. One position provides a level which substantially fills the basket 11, a second setting provides about two-thirds of a basket, a third setting shuts off the incoming water when it reaches about half the height of the basket, and the fourth lowest level which will be more fully discussed in connection with the present invention shuts off the incoming water when it reaches a very low level in the tub which may well not even rise to the bottom of the basket 11.
In the direction of rotation which is provided for the washing operations the motor 26 drives a pump 40 through a flexible coupling 41 in the appropriate direction to discharge liquid from the bottom of the tub 13 into a conduit 42 which leads to a nozzle 43. The nozzle 43 is positioned relative to a filtering member 44 secured on the top of the agitator 20 so as to be movable therewith so that liquid is recirculated by pump 40 hooked up through the conduit 42 and out of the nozzle 43 into the oscillating filter pan 44. It will be observed that the filter pan 44 has a substantial number of small openings 45 formed therein so that the water coming from the nozzle 43 passes down through the openings 45. The filter pan 44 with its many small openings and its upstanding side walls causes the lint, which is separated from the clothes during the washing operation, to be filtered out of the water and thus prevents it from being redeposited on the clothes.
Hot and cold water may be supplied to the machine through conduits 46 and 47 which are adapted to be connected respectively to sources of hot and cold water (not shown). Conduits 46 and 47 extend into a valve structure having solenoids 48 and 49 and being connected to a hose 51.
Also secured on the agitator so as to move therewith is a clothes containing basket 50 which is small relative to the basket 11 and the tub 13. The basket 50, except for overflow openings 52 adjacent the top thereof, is imperforate. The lower inner portion of the annular basket 50 may be formed to accommodate the tops of the vanes 54 of the agitator 20, in addition providing small washing vanes within the basket 50 itself. This positions the basket 50 securely on the agitator 20 so that there will not be any relative rotation of the two. The basket 50 is positioned below the filter pan 44 so that water which is poured into the filter pan from the nozzle 43 passes through the openings 45 in the filter pan 44 down into the basket 11. Thus, in effect the filter pan affects a filtering action of the water prior to its entry into the basket 11.
The filter pan 44 and basket 50 are preferably removably positioned on the agitator 20 so that they may be removed when so desired, for instance, for inserting clothes into the basket 11 and readily replaced on the agitator 20 secured thereto as to move therewith. It should be noted that the filter pan does not form a part of the present invention and its use is optional.
Completing the description of the structure, when enough washing has been provided and is intended to remove the washing liquid from the clothes the direction of rotation of the motor is reversed. As described above, this causes the basket 11 and agitator 20 to rotate together at a relatively high speed so as to centrifuge the washing liquid out through the openings 12. The washing liquid thus removed is caused by the pump 40 rotating in the reverse direction to the previous rotation thereof to discharge into a conduit 56. The conduit 56 is adapted for discharge to a drain line 58 so that the pump 40 is effective to drain the tub 13.
As mentioned herein above, the control member 38 may be used to provide four different water levels in the tub 13, three of them being operative to provide water within the basket 11 and one of them being at such a low level within the tub 13 that there is insufficient water in the basket 11 to provide any washing action. This last low water level is provided when generally it is desired to use the small basket 50 to wash a very small load which generally occurs when delicate or heavily soiled garments of the type which constitute a small minority of all clothes worn must be washed and there is insufficient quantity to justify the use of the large basket 11.
In accordance with the present invention the small basket 50 is adapted to be used, as will be explained fully hereinafter, to wash a small quantity of clothes in a very high detergent concentration relative to the amount of water in the basket 50. In this instance the use of the small basket and a high concentration of detergent enhances the stain removal capability of the washing machine.
Use of the basket 50 and its cycle of operation in washing a normal small quantity of clothes will now be described. When such a load is to be washed the small basket 50 is placed on the agitator mechanism as shown and the filter pan 44 is then placed over the small basket 50.
When the lowest liquid level selected is reached in the basket and outer tub as described the motor 26 starts operation in the direction suitable for moving the agitator mechanism. As described this also causes the pump 40 to operate in the direction to pump water up through the conduit 42 and out from the nozzle 43 into the filter pan 44. This water then passes through the openings 45 in the filter pan 44 down into the basket 50 containing a small quantity of clothes. Because the basket 50 is substantially imperforate the water quickly rises in the basket regardless of the fact that the basket 11 does not have any water or virtually no water in it. The water continues to rise in the basket 50 until it reaches substantially to the level of the overflow outlets 52.
As mentioned above, in accordance with the present invention provision is made to employ the small basket 50 to wash a small quantity of clothes having a heavy soil concentration in a relatively small volume of water. This enables the user to establish a high concentration of detergent while using a relatively small volume of water and detergent. To this end, circulation of liquid to the basket 50 is terminted once the liquid level reaches the overflow apertures 52. At this point in time, because of the relatively small volume of water in the basket 50 the clothes can readily be washed in a high concentration of detergent during a heavy soil removal cycle of operation while using reasonable amounts of detergent. To this end, a pinch valve 59 is provided which is operated by a solenoid 60 arranged in conduit 42. The solenoid 60 is energized to cut recirculation flow to the basket 50 after a predetermined amount of time. In carrying out the present invention as will be explained hereinafter the solenoid is activated to cut of the flow of water to basket 50 after 30 seconds which time was found appropriate to transfer a volume of water from tub 13 sufficient to fill the basket 50.
In the lowest water level selection the water volume in the outer tub and basket is greater than needed to fill the small basket 50. While it might result in using less water by filling the small basket directly, controlling the temperature of the wash water would be difficult if not impossible. This is especially true in selecting a hot water wash since the initial flow would normally be cold until the lines are purged. Because of the relatively small volume of water required to fill the small basket it will, in most instances, fill with cold water before the supply line is purged and the hot water reaches the basket 50.
Accordingly, in the present instance this problem is eliminated by first filling the outer tub and basket in the normal manner. This volume of water even at the lowest water setting is sufficient to purge the hot water supply line of cold water and still provide adequate hot water for the wash cycle.
Completing now the description of the electrical control system for machine of FIG. 1, reference is made to FIG. 2. A sequence control assembly 85 (FIG. 1) includes a timer motor 87 which drives a plurality of cams 88, 89, 90 and 91. These cams during their rotation by the timer motor actuate various switches (as will be described), causing the machine to pass through the cycle of operation which includes washing, spinning, rinsing and spinning.
The electric circuit as shown in FIG. 2 is energized from a power supply (not shown) through a pair of conductors 92 and 93. Cam 88 controls a switch 94 which includes contacts 95, 96 and 97. When the cam has assumed the position where all three contacts are separated as shown, washer 10 is disconnected from the power source and is inoperative. When operation of washer 10 is to be initiated, as will be explained below switch 94 is controlled by cam 88 so that contacts 95 and 96 are energized. When a main switch 98 is closed (by any suitable manual control not shown), power is then provided to the control circuit of the machine from the conductor 92 through contacts 95 and 96. From contact 96 the circuit is completed from conductor 99 through switch 101 controlled by cam 89 and a manually operated switch 100. In the "up" position the switch 101 completes a circuit for the cold water solenoid 45 independently of switch 100; in the "down" position shown, the switch 101 completes a circuit for the hot water solenoid 46. Thus, when the switch 100 is open energization of solenoids 48 and 49 is under control of switch 101, but when switch 100 is closed the cold water solenoid may be energized independently of the position of switch 101.
From the hot and cold water solenids, the energizing circuit then extends through a conductor 102 and then to a coil 103 of a relay 104, the main or run windings 105 of motor 26, a conventional motor protector 106, a switch 107 controlled by cam 91, and the conductor 93.
Motor 27 is of the conventional induction type which is provided with a start winding 108 which assists the main winding 105. Current through relay 103 causes switch 109 to close, thereby energizing the start winding in parallel with the main winding through a conduit 110 of switch generally indicated at 111 and which is controlled by cam 90, contact arm 112, the relay contact 109, the start winding 108, a contact arm 113, and the contact 114 of switch 111.
A circuit is also completed in parallel with motor 27 through the timer motor 87. Relay 104 is designed to close contact 109 when a relatively high current is passing through it. When the main winding 105 of motor 27 is in series with valve solenoids 45 and 46, as described, a much lower impedance is presented in the circuit by the motor 27 than is presented by the valve solenoids. As a result, the greater portion of the supply voltage is taken up across the solenoids. This causes whichever of the solenoids is connected in the circuit to be energized sufficiently to open its associated water valve. This action continues with the circuits thus arranged, so that water is admitted to the basket 11 and tub 13. Because of the perforations in basket 11 the water rises in both basket 11 and tub 13 at the same rate.
Water level control switch 77 of water level control 38 is connected across conductors 99 and 102 as shown, so that when switch 77 closes, it excludes the solenoids 48 and 49 from the effective circuit by short circuiting them. As a result, the solenoids become de-energized and a high potential drop is provided across winding 105 of motor 27. This causes the relay 104 to close switch 109 to start the motor 27 while at the same time, timing motor 87 starts so as to initiate the sequence of operations. The switch 107 is in series with the main motor 27 but not in series with the timer motor 87. Thus, by the opening of switch 107, the energization of motor 27 may be stopped. The timer motor will continue to operate though, as a result of the fact that timer motor 27 is deliberately provided with an impedance much greater than the valve solenoids so that it will take up most of the supplied voltage and the solenoids therefore do not operate their respective valves.
A further point of the circuit of FIG. 2 is that when switch arms 112 and 113 are moved by cam 90 to engage contact 114 and a contact 115 respectively, the polarity of the start winding is reversed. The circuit from conductor 102 then proceeds through contact 115, contact arm 112 to start winding 108, relay contact 109, contact arm 113 and contact 114 to the protective device 106 and conductor 93. Thus, provided motor 27 is stopped or slowed down so that relay contact 109 is closed, the reversal of switch 111 is effective to cause the motor 27 to rotate in the opposite direction when the motor is started up again.
In order to energize motor 27 independently of the water level switch 77 and the valve solenoid, so that a spin operation may be provided without regard to the absence of the predetermined water valve, the cam 88 is formed so that it may close all three contacts 95, 96 and 97 of switch 94 during centrifugal water extraction. When this occurs, it causes the power to be supplied from conductor 92 directly through contact 97 to conductor 102 and the motor 27 rather than through the water level switch or the valve solenoids.
In the machine thus far described the small basket 50 provides means for isolating and confining a limited water volume in the range from 1.0 to 2.5 gallons during the activation or wash cycle of operation. This ability to confine a limited water volume in the wash cycle of operation allows for the attainment of very high detergent concentrations in the range from 0.8 to 3.3 weight percent based on the usage of reasonable and acceptable amount of detergent in the range from 75 to 125 grams. The high concentration of detergent achieved together with the agitation provided during the wash cycle of operation have been found to enhance washing performance significally. By way of comparison, these detergent concentrations were 8 to 33 times that commonly achieved in washing clothes in the larger clothes basket.
In carry out the wash cycle of operation in the small basket 50 in accordance with the present invention, a low water wash cycle control assembly 120 is provided. The control includes a manually settable dial 121. The dial 121 is used to initiate operation of a timer motor 119 which drives cams 122 and 123. These cams 122 and 123 during their rotation by the timer motor actuate switches 124 and 125 respectively. To initiate the controlled water level wash system in the small basket 50 the water level control 38 is set at the lowest water level position. The sequence control 85 is set in the normal manner to initiate a wash cycle, and the dial 121 is set so that switch contact 126 of switch 124 is closed.
At this point in time the solenoid 48 and 49 are energized and water fills into the tub to the lowest water level. As water level switch 77 closes shorting out the fill solenoids, power is made available to the motor 27 in the manner described above, and at the same time timer motor 119 is energized through line 102 and contact 126 of switch 124. The timer cam 122 is designed to maintain the operation of timer motor 119 through switch contact 126 for approximately 30 seconds, after which time the contact 126 opens to deenergize timer motor 119. During operation of the timer motor 119 the water in the tub 13 is recirculated in the normal manner to fill the small basket 50 as described above. At the time cam 122 opens the circuit to timer 119 cam 123 closes switch 125 to energize solenoid 60 of pinch valve 59. This prevents further recirculation of water from the tub 13 to the small basket 50 thereby insuring that clothes placed in basket 50 will in fact be washed in the limited or preselected volume of water. In carrying out the present invention it has been determined that the appropriate amount of water is transferred from the tub 13 to the basket 50 in the range of between 20 and 40 seconds. At the completion of the wash and the ensuing centrifugal extraction operation removes the water from basket 50 through openings 52. In the following rinse cycle water is once again introduced into the tub 13. When water level switch closes once again after this second fill, the switch 77 will close establishing a circuit to motor 27 to rinse the clothes in basket 50. At this time a circuit to the timer 119 is completed through cam switch 112, relay switch 109 and, the second contact 128 of switch 124. Once energized through contact 128 the timer motor 119 due to design of cam 126 will in effect run itself out, as indicated in the cam chart illustrated in FIG. 3. The opening of the circuit to timer 119 insures that the following cycles of operation including the rinse portion of the washing cycle will take place with the recirculation system operating. In effect during the remaining cycles of operation all of the fill water will be circulated through the clothes in basket 50. This insures that detergent even in the concentrated proportion will be rinsed or purged from the clothes during the remaining cycle of operations.
It should be apparent to those skilled in the art that the embodiment described heretofore is considered to be the presently preferred form of this invention. In accordance with the Patent Statues, changes may be made in the disclosed apparatus and the manner in which it is used without actually departing from the true spirit and scope of this invention. | This invention relates to automatic clothes washing machines, and more particularly to an improved structure in such machines for affecting the washing of very small loads of clothing in a high detergent concentration. The clothes washing machine has wash, rinse and spin extraction operations including an outer imperforate tub, an agitator, a first basket within the tub, a second smaller basket disposed within the first basket and positioned on the agitator for movement therewith. There is also a water supply for feeding water into the machine, drive system for operating the agitator to effect washing of clothes and for rotating the basket to centrifugally extract water from the clothes. Water is allowed to flow from the basket to the tub and may be recirculated from the tub into the baskets. The improvement is a controlled recirculation system wherein only a predetermined volume of water is transferred from the outer tub to the small basket by the recirculation system. This allows clothes placed in the small basket to be washed in a high detergent concentration relative to the predetermined volume of water in the small basket and independent of the amount of water in the tub and to then be rinsed during continuous recirculation of water from the outer tub. | 3 |
CROSS REFERENCES
[0001] This application is a continuation-in-part of co-pending U.S. application Ser. No. 10/411,535 filed Apr. 10, 2003.
TECHNICAL FIELD OF THE INVENTION
[0002] The present invention relates generally to door frames and, more particularly, to a modular sill assembly which may be vertically adjusted and adapted for a variety of doorway configurations.
BACKGROUND OF THE INVENTION
[0003] In a standard threshold assembly, a sloping sill is attached to a base. The sill is oriented on the exterior of the door frame. A trim piece or nosing is generally attached to the opposite side of the base facing the interior of the door frame. Between the sill and trim piece, a riser or threshold cap is attached to the top of the base. The riser is positioned to underlie the door when it is in a closed position and form a seal with the bottom of the door.
[0004] Several methods of attaching the riser to the base exist in the prior art. In particular, a number of these prior art designs provide for adjustment in the height of the riser relative to the base. These prior art designs tend to incorporate mechanisms, for example, corresponding nut and screw assemblies, that are fixed in position relative to the length of the base.
[0005] The manufacture of the individual pieces comprising a sill assembly and the method of attaching the riser to the base have presented numerous design issues to the millwork industry. One particularly troublesome issue is the fact that, doorways, come in a large variety of configurations. For instance, a door frame may accommodate a door and a non-moving sidelight or a pair of opposing (“french”) doors and an astragal, which may or may not be attached to one of the opposing doors. Current sill designs can be used in a limited number of configurations and provide little flexibility in the available configurations. While manufacturers have attempted to design threshold assemblies that are adaptive in some aspects, none have produced a design that provides sufficient adaptability. As mentioned above, the prior art designs generally utilize attachment mechanisms that are fixed in position relative to the length of the base.
[0006] Furthermore, these prior art designs utilize a large amount of custom hardware, particularly in their attachment mechanisms, such as specialized shoulder screws and push nuts. This custom hardware increases the cost of the sill assembly and requires that manufacturers stock a large amount of custom pieces for which they have no other use.
[0007] An improved sill assembly would preferably have a modular design that is capable of ready adaptation to various doorway configurations, while requiring a minimal amount of custom hardware for assembly.
[0008] The present invention is directed to overcoming one or more of the problems set forth above.
SUMMARY OF THE INVENTION
[0009] An aspect of the present invention is to provide a modular sill assembly that is easily adapted to a variety of different doorway configurations.
[0010] Another aspect of the present invention is to provide a modular sill assembly that utilizes a means of connecting a riser to a substrate that is easily adaptable to whatever length and arrangement is required by a particular doorway design.
[0011] Yet another aspect of the present invention is to provide a modular sill assembly that utilizes a minimal number of custom parts for assembly, thereby enhancing interchangability of parts in the system.
[0012] Another aspect of the present invention is to provide a modular sill assembly with a height-adjustable riser that can be adjusted without the need for a visible adjustment mechanism.
[0013] In accordance with the above aspects of the invention, there is provided an adjustable threshold assembly that includes an elongated substrate base composed of a molded composite material; a sill plate connected with the substrate base; a riser having a top and two downwardly-extending legs defining an interior of the riser, said interior of the riser having a first flange and a second flange angling downward and toward one another; and means for supporting the riser on the substrate base including an adjusting screw and a corresponding T-nut, said adjusting screw having a head adjacent the substrate base and said T-nut slideably supported by the first and second flanges and wherein the riser is supported by the substrate base by threading the adjusting screw into the T-nut.
[0014] In another embodiment, the adjusting screw is provided with an extended head that extends beyond the legs of the riser, thereby enabling adjustment of the screw by direct engagement and turning of the extended screw head.
[0015] These aspects are merely illustrative of the innumerable aspects associated with the present invention and should not be deemed as limiting in any manner. These and other aspects, features and advantages of the present invention will become apparent from the following detailed description when taken in conjunction with the referenced drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] Reference is now made to the drawings which illustrate the best known mode of carrying out the invention and wherein the same reference numerals indicate the same or similar parts throughout the several views.
[0017] [0017]FIG. 1 is a perspective view of a doorway incorporating a sill assembly according to an embodiment of the present invention.
[0018] [0018]FIG. 2 is a cross-sectional view of the sill assembly of FIG. 1 taken along line Z-Z.
[0019] [0019]FIG. 3 is a partial section perspective view of an embodiment of a sill assembly illustrating a T-nut/screw fastening assembly.
[0020] [0020]FIG. 4 is a cutaway view of an embodiment of a sill assembly
[0021] [0021]FIG. 5 is a perspective view of an embodiment of a sill assembly for a doorway including an active door and sidelight or non-active door.
[0022] [0022]FIG. 6 is a cross-sectional view of another embodiment of a sill assembly incorporating an alternate riser support arrangement.
[0023] [0023]FIG. 7 is a cross-sectional view of yet another embodiment of a sill assembly incorporating a second alternate riser support arrangement.
[0024] [0024]FIG. 8 is a cross-sectional view of an alternate embodiment of a sill assembly incorporating the riser support arrangement of FIG. 6.
[0025] [0025]FIG. 9 is a cross-sectional view of yet another embodiment of a sill assembly incorporating the riser support arrangement of FIG. 6.
DETAILED DESCRIPTION
[0026] [0026]FIGS. 1-4 illustrate a sill assembly shown generally at 10 including a substrate 12 , a sill 14 , a riser 16 , and a trim piece 18 . FIG. 1 illustrates a sill assembly 10 of this design installed in a door frame 20 between the door jambs.
[0027] The substrate 12 shown in FIGS. 1-4 is generally rectangular in shape with a number of grooves formed therein. In the embodiment shown, the top surface 26 of the substrate 12 includes a first sill groove 28 . The bottom surface 30 of the substrate 12 includes a second sill groove 32 . The first and second sill grooves 28 , 32 aid in securing the sill 14 to the substrate 12 . The substrate 12 is also provided with a first trim groove 34 in the top surface 26 and a second trim groove 36 in the bottom surface 30 . These grooves aid in securing the trim piece 18 to the substrate 12 . The top surface 26 of the substrate 12 also includes a T-shaped slot 38 that extends along the entire length of the substrate 12 and opens to the top surface 26 . In a preferred embodiment, the substrate 12 is manufactured from a composite material that is processed to form the desired cross-section for the substrate.
[0028] The riser 16 includes a top surface 40 and first 42 and second 44 legs extending generally downward from the top surface. The top surface 40 , first leg 42 and second leg 44 define an interior 46 of the riser 16 . A first flange 48 and a second flange 50 are located within the interior 46 of the riser 16 . In the embodiment shown, the first flange 48 emanates from the first leg 42 and the second flange 50 is supported by the top surface 40 of the riser. However, the flanges 48 , 50 may be supported by the first and second legs, respectively, the top surface 40 , or the top surface 40 and second leg 44 , respectively. Advantageously, the first and second flanges 48 , 50 angle downward and toward one another forming a generally V-shaped structure with an opening 60 at the vertex of the flanges. An extension 52 , 54 is located at the end of each flange 48 , 50 . Preferably, the extensions 52 , 54 are made of a softer durometer material than the rest of the riser 16 , such as a plastic material. The riser 16 itself is preferably made of an extruded plastic material, although a number of extrudable materials are suitable. In a preferred embodiment, the extensions 52 , 54 are co-extruded with the rest of the riser. The riser 16 also includes a sealing leg 56 extending out and downward from the top surface 40 of the riser 16 . The sealing leg includes a sealing extension 58 that extends into the space between the sealing leg 56 and first leg 42 . The sealing leg 56 and extension 58 engage the sill in manner described below in order to form a weather seal for the sill assembly.
[0029] During installation, the riser 16 is positioned on top of the substrate 12 with the opening 60 at the vertex of the flanges located generally above the T-shaped slot 38 . A T-nut 62 having a flange 64 is inserted into the T-shaped slot 38 with first and second lateral extensions 66 , 68 of the slot accommodating the flange 64 . A corresponding screw 70 is inserted between the flanges 48 , 50 , with the flanges supporting the head of the screw 70 and the threaded portion of the screw extending through the opening 60 between the flanges. The extensions 52 , 54 of the flanges engage the screw 70 to restrict both vertical and lateral movement of the screw, thereby eliminating any need for a push nut or similar structure to secure the screw. This, in turn, eliminates the need to use special fasteners, for example, screws having shoulders designed to accommodate push nuts. Any standard screw of suitable length may be used instead. In order to secure the riser 16 to the substrate 12 , the screw 70 is inserted into the T-nut 62 , and the screw 70 is tightened. The height of the riser 16 relative to the substrate 12 is adjustable by varying the extent to which the screw 70 is tightened into the T-nut 62 . The riser 16 is preferably provided with a number of access holes 72 in the top surface 40 through which a screwdriver may be inserted in order to tighten the screw 70 . Caps 73 are provided to cover the access holes 72 and present a finished appearance. At least two T-nuts with corresponding screws are generally necessary to securely fasten the riser to the substrate in a level manner. In a preferred embodiment, a T-nut with a corresponding screw is positioned approximately every ten inches along the sill assembly.
[0030] The slot 38 allows the T-nut 62 to be positioned anywhere along the length of the substrate 12 . Similarly, the flanges 48 , 50 permit lateral movement of the screw 70 along the length of the riser 16 , although such movement does require some force due to the restriction of the extensions 52 , 54 , to allow the screw 70 to be positioned anywhere along the length of the riser. This feature allows the position of the T-nut and screw fastening assemblies to be varied along the length of the riser/substrate subassembly. This arrangement enhances the modularity of the sill assembly by permitting greater interchangeability of parts.
[0031] The sill 14 features a sloping top surface 74 having a number of ridges designed to enhance traction. On the underside of the sill 14 are located a front support 76 and a rear support 78 . Each of the supports 76 , 78 is provided with a lateral extension 80 , 82 . The front extension 80 is arranged to engage the second sill groove 32 in the substrate, while the rear extension 82 engages the first sill groove 28 to connect the sill 14 with the substrate 12 . The sill 14 also includes a sealing lip 84 which engages with the sealing leg 56 and extension 58 to form a weather seal. The remaining features of the sill 14 are generally known in the art and, therefore, will not be described in more detail.
[0032] The trim piece 18 is preferably made from a material similar to that used for the riser 16 . Furthermore, both the riser 16 and trim piece 18 are provided with an identical finish in order to provide the sill assembly with aesthetically pleasing visible surfaces. The trim piece includes first and second connecting extensions 86 , 88 which engage with the first and second trim grooves 34 , 36 in the substrate, respectively, to secure the trim piece to the substrate.
[0033] It is envisioned that each of the primary pieces of the sill assembly, the substrate, riser, sill and trim piece, will form a modular system in which these pieces may be interchanged. The easy adaptability of the system will decrease manufacturing costs and the amount of inventory a manufacturer must carry. Furthermore, because the screws used in the assemblies are standard, the amount of custom hardware necessary to assemble the product is minimized.
[0034] [0034]FIG. 5 illustrates an embodiment of the sill assembly in a doorway having a door and a sidelight. The sill assembly 10 lies in a door frame (not shown in detail). A mullion 90 is positioned in the door frame between a door (not shown) and a sidelight 94 . A riser 16 attached to a substrate (not shown), as described above, extends under the door between one outer jamb and the mullion 90 . Between the mullion 90 and the other outer jamb, a sidelight adapter 96 , or fixed sill, is attached to the substrate to provide a level surface for installing the sidelight 94 . Like the other pieces of the system, the sidelight adapter 96 is intended to be extruded in a few standard lengths and cut to length at the installation site. A mullion adapter 98 is attached to the substrate between the riser 16 and the sidelight adapter 96 and provides a level surface for mounting the mullion 90 . This eliminates the need to cut the profile of the sill assembly into the mullion 90 .
[0035] The above components are also suitable for use in patio or french doors. These doorways usually include dual opposing doors separated by an astragal. One of the opposing doors is generally kept fixed most of the time and is referred to as the non-active door. The astragal may be attached to one of the opposing doors but is usually attached to the non-active door. In this arrangement, a fixed sill can be attached to the substrate underneath the non-active door and the astragal, while a riser 16 can be positioned underneath the operating door. The modular design of the sill assembly allows the riser 16 and fixed sill to be easily configured whether the non-active door is on the right or left side of the doorway.
[0036] [0036]FIG. 6 illustrates an alternate arrangement for supporting a riser 116 in a modular sill assembly. In the embodiment shown in FIG. 6, the remaining elements of the modular sill assembly are largely identical to the first embodiment shown in FIGS. 1-4. The sill includes a substrate 112 , a sill 114 , and a trim piece 118 . However, in the embodiment illustrated in FIG. 6, an adjusting screw 170 used to support the riser 116 is inverted relative to the arrangement shown in FIGS. 1-4. This allows the head of the adjusting screw 170 to serve as a pedestal that rests on the top surface of the substrate 112 . Alternately, the head 171 of the adjusting screw 170 may be inserted into the T-slot 138 of the substrate 112 . A T-nut 162 is secured between first 148 and second 150 flanges of the riser 116 . First 152 and second 154 extensions on the riser flanges engage the T-nut 162 to restrict both vertical and lateral movement of the nut. The first and second flanges 148 , 150 and first and second extensions 152 , 154 are spaced slightly wider than their counterparts in the embodiment shown in FIGS. 1-4 to accommodate the slightly wider diameter of the T-nut 162 . The T-nut 162 is threaded onto the adjusting screw 170 . A pair of tracks 155 , which extend along the length of the underside of the riser 116 , engages the flange 164 of the T-nut 162 and hold it a slight distance from the underside of the riser 116 . By moving the T-nut 162 slightly away from the underside of the riser 116 , the available room for raising the adjustment screw 170 is increased, thereby increasing the adjustment range of the system. In a preferred version of the embodiment, the adjusting screw 170 is provided with a slot (not shown) at the end opposite the head 171 and which faces upward. The slot allows easy adjustment of the riser height by turning the adjustment screw 170 and thereby moving the T-nut 162 upwards or downwards relative to the screw. Access holes (not shown) in the top of the riser 116 provide access to the adjusting screw 170 .
[0037] [0037]FIG. 7 illustrates a slightly different version of the embodiment of FIG. 6. While the riser support arrangement is identical to that shown in FIG. 6, the substrate 212 of this embodiment is not provided with a T-slot. The T-slot is not required for the alternate riser support arrangement, and elimination of the slot reduces the overall cost of producing the substrate.
[0038] The embodiments illustrated in FIGS. 6 and 7 include a sill sealing lip 184 provided with a ridge 185 running along the entire length of the sealing lip. The ridge 185 engages the sealing leg 156 and sealing extension 158 of the riser 116 to create an improved seal between the two pieces. A series of secondary ridges 187 are utilized on both sides of the sealing lip 184 to help secure the engagement of the sealing lip 184 and the sealing leg 156 regardless of the adjusted height of the riser 116 .
[0039] In yet another alternate embodiment as shown in FIG. 8, the substrate 312 is provided with a hole 313 extending perpendicularly therethrough. The axis of the hole 313 is coextensive with the center of and communicates with T-slot 338 . The remainder of the embodiment is similar to that illustrated in FIG. 6. The hole provides access to the head of the adjusting screw 170 from the underside of the substrate 312 . This arrangement allows adjustment of the riser height without the need for access holes in the top surface of the riser when the threshold assembly is installed into a door frame prior to the frame being installed at the construction site, for example, in the case of pre-hung door frames that are assembled at a factory prior to shipment to a distributor or directly to a construction site. Elimination of access holes in the top surface of the riser provides a more aesthetic assembly and also eliminates a possible entry point for moisture into the interior of the assembly. As with the embodiments shown in FIGS. 6 and 7, this arrangement can also be provided without the T-slot 338 .
[0040] [0040]FIG. 9 illustrates an alternate embodiment of the riser. In FIG. 9, adjusting screw 470 is provided with an oversized head 471 . The oversized head 471 extends beyond the second leg 444 of the riser 416 . In order to accommodate the oversized head 471 , the first 442 and second 444 legs of the riser 416 are slightly shorter than those of the risers in the above-described embodiments. The legs of the riser 416 do not extend entirely to the top surface of the substrate, thereby leaving a gap between the bottom of the legs and the top of the riser. This gap accommodates the oversized head 471 of the adjusting screw 470 and allows the screw to extend beyond the legs. Alternatively, a slot is provided in the second leg 444 of the riser 416 to accommodate the oversized head 471 . Depending on the configuration of the riser 416 , a corresponding slot in the first leg 442 of the riser 416 may also be necessary to fully accommodate the oversized head 471 . These arrangements allow direct manipulation of the oversized head 471 of the adjustment screw 470 and, consequently, adjustment of the riser height. The trim piece 418 is removed in order to gain access to the adjustment screw 470 . The trim piece 418 may also be made from a flexible plastic material that will allow it to be partially pulled away from the riser to expose the oversized head 471 of the adjusting screw 470 without the need to remove the trim piece from the assembly. In this embodiment, access holes in the top surface of the riser are not necessary. This provides a smooth and unblemished top surface for the riser, which provides improved aesthetics for the assembly.
[0041] Other objects, features and advantages of the present invention will be apparent to those skilled in the art. While preferred embodiments of the present invention have been illustrated and described, this has been by way of illustration and the invention should not be limited except as required by the scope of the appended claims and their equivalents. | An adjustable sill assembly includes a substrate base; a sill plate connected with the substrate base; a riser having a top and two downwardly-extending legs defining an interior of the riser, said interior of the riser having a first flange and a second flange angling downward and toward one another; and means for supporting the riser on the substrate base including an adjusting screw and a corresponding T-nut, said adjusting screw having a head adjacent the substrate base and said T-nut slideably supported by the first and second flanges and wherein the riser is supported by the substrate base by threading the adjusting screw into the T-nut. In another embodiment, the adjusting screw is provided with a head that extends beyond at least one of the downwardly-extending legs of the riser to allow engagement and turning of the adjusting screw from the side of the riser. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates in general to a sewing machine, and more particularly to a material feeder of the sewing machine, which feeds the sewing machine with a narrow and long material which is to be sewed.
2. Description of the Prior Art
In order to sew a narrow and long material with a sewing machine, there has been proposed a material feeder which comprises a rotatable bobbin on which the material is wound. Upon requirement of sewing, a leading end of the material is drawn from the bobbin and brought to a work portion of the sewing machine where a stitching needle and a material conveyor are positioned. During sewing operation, the material conveyor draws the material intermittently from the bobbin in response to the reciprocating movement of the needle. However, this intermittent material drawing by the conveyor causes application of considerable tension to the material due to an inevitable resistance of the bobbin against the drawing, viz., against the turning of itself. The tension tends to produce unsightly creases on the stitched material when the same is released from the sewing machine.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide an improved material feeder, for a sewing machine, which is free of the above-mentioned drawback.
According to the present invention, there is provided a material feeder from which a narrow and long material to be stitched is fed intermittently to the sewing machine without appliying a tension to the material.
According to the present invention, there is provided, in a sewing machine for sewing a narrow and long material which is drawn from a bottin, a material feeder which comprises first means for drawing a predetermined length of the material from the bobbin when actuated, and second means for actuating the first means when the length of the material drawn from the bobbin is reduced to a predetermined degree.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects and advantages of the present invention will be apparent from the following description when taken in conjunction with the accompanying drawings, in which:
FIG. 1 is a schematic side view of a material feeder for a sewing machine, according to the present invention;
FIG. 2 is a sectional view taken along the line II--II of FIG. 1;
FIG. 3 is a view taken from the direction of the arrow III of FIG. 1;
FIG. 4 is a view taken from the direction of the arrow IV of FIG. 1; and
FIGS. 5A and 5B are views taken from the direction of the arrow V of FIG. 4, showing different conditions.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIG. 1, there is shown a material feeder 10 of the present invention, which is incorporated with a known sewing machine 100. The sewing machine 100 illustrated is disposed on a table 102 mounted on a carrier 104 in which, as will be described hereinafter, the material feeder 10 is installed. Designated by numeral 106 is an eye-pointed needle of the sewing machine 100, which stitches a narrow and long material M which is drawn thereto from the material feeder 10. A known material conveyor 108 is arranged below the needle 106 to intermittently convey the material M forward during sewing operation of the sewing machine 100.
As is seen from FIG. 1, the carrier 104 is of a skeleton construction which comprises a pair of upper beams 104a and a pair of lower beams 104b which are supported horizontally by a rollaway frame 104c.
The material feeder 10 comprises a plurality of bobbins 12a, 12b, 12c, 12d, 12e and 12f (six in the disclosed embodiment) which are divided into two, viz., upper and lower groups each including the bobbins 12a to 12c or 12d to 12f, as is seen from FIG. 2. The bobbins 12a to 12c of the upper group are rotatably supported through an upper common shaft 14 by the upper beams 104a, while the bobbins 12d to 12f of the lower group are rotatably supported through a lower common shaft 16 by the lower beams 104b. Each bobbin has a narrow and long material M wound thereon, which material is to be stitched by the needle 106. As is best seen from FIG. 2, six guide pipes 18a, 18d, 18b, 18e, 18c and 18f are arranged abreast forward in the carrier 104a at the position between the upper and lower beams 104a and 104b but downstream of the bobbins 12a to 12f with respect to the flow of the narrow and long material M. Each guide pipe is located in the way of a material M drawn from the corresponding bobbin, as is understood from FIG. 2. Although not shown in the drawings, a suitable beam is arranged in the carrier 104 to support the guide pipes 18a to 18f. As is seen from FIG. 1, each guide pipe has a funnel-shaped opening 18a' for facilitating insertion of the material M thereinto. As will be described hereinafter, usually, all of the materials M are passed through the respective guide pipes 18a to 18f and upon sewing operation, one of them M is intermittently pulled toward the sewing machine 100 to be stitched.
Behind the guide pipes 18a to 18f, there is arranged a material drawing mechanism 20 which functions to intermittently draw selected one of the materials M from the corresponding bobbin in response to sewing operation of the sewing machine 100. The mechanism 20 comprises a roller bar 22 which is positioned behind the guide pipes 18a to 18f and extends along the row of the guide pipes, as is seen from FIG. 3. Preferably, the roller bar 22 has an elastomeric outer layer. As may be understood from FIG. 1, the roller bar 22 is rotatably supported by spaced parts of the vertically extending portion of the carrier 104. As is seen from FIG. 3, the roller bar 22 is driven in the direction of the arrow "α" (see FIG. 1) by an electric motor 24 which is, in turn, controlled by a control unit 26 with a timer 28. As will be described hereinafter, due to the work of the timer 28, the rotation of the roller bar 22 is made periodically.
As is seen from FIGS. 1 and 3, below the roller bar 22, there are arranged a plurality (six in the embodiment) of pressing followers 30a, 30d, 30b, 30e, 30c and 30f, each being capable of pressing the corresponding material M against the roller bar 22 when assuming a lifted position. For this, each pressing follower is located in the way of the corresponding material M, as is seen from FIG. 3, and comprises a holder 32 fixed to a piston rod 34 of an air cylinder 36, and a roller 38 rotatably connected to the holder 32. Preferably, each roller 38 has an elastomeric outer layer. As may be understood from FIG. 1, the air cylinders 36 are fixed to the vertically extending portion of the carrier 104.
Referring back to FIG. 3, each pressing follower 30a, 30d, 30b, 30e, 30c or 30f can assume two positions, viz., a rest or down position wherein, as is shown in the drawing, the roller 38 is separated from the roller bar 22 and an upper or up position where the roller 38 is pressed against the roller bar 22. That is, as is seen from FIG. 1, upon application of compressed air to a cylinder 36, the corresponding piston rod 34 is lifted to move the corresponding roller 38 to the operative position illustrative by a broken line wherein the corresponding material M is compressed between the roller bar 22 and the roller 38. Thus, in this condition, rotation of the roller bar 22 in the direction of the arrow "α" forces the material M to move downstreamly, that is, toward the sewing machine 100.
At a downstream portion of the material drawing mechanism 20, there is pivotally arranged an antenna 40 which has a sufficient length to extend across the ways of the materials M which come from the material drawing mechanism 20. The antenna 40 is pivotal between the lower position illustrated by a solid line and an upper position illustrated by a broken line. Although not shown in the drawing, a suitable biasing means, such as spring or the like, is associated with the antenna 40 to bias the same downward, that is, toward the lower position, and suitable stoppers are arranged to suppress extreme movement of the antenna 40. A limit switch 42 connected to the control unit 26 for the motor 24 is located adjacent the antenna 40 to associate therewith. That is, when the antenna 40 assumes the upper position illustrated by the broken line, the switch 42 assumes its ON position and thus energizes the motor 24 for a given period of time.
Beneath the table 102 of the sewing machine 100, there is mounted a holder 44 which functions to hold leading ends of the materials M when the latter are not subjected to sewing by the sewing machine 100. As is seen from FIG. 4, the holder 44 comprises a box, and six identical catch devices 46a, 46d, 46b, 46e, 46c and 46f which are arranged in the body, side by side. As is shown in FIG. 5A, each device comprises a switch 48 with an antenna 50, and a curved pivotal lever 52 the free end of which is in contact with the antenna 50 of the switch 48. Each switch is connected to an electromagnetic valve (not shown) by which air-feeding to the corresponding air cylinder 36 is controlled. The switch assumes its ON position when the antenna 50 is lifted as shown in FIG. 5A, and its OFF position when the antenna 50 is lowered as shown in FIG. 5B. The switch 48 is equipped with a suitable biasing means, such as a spring or the like, for biasing the antenna 50 toward the lifted, viz,. ON position of FIG. 5A. Thus, when the switches 48 are in their ON positions as shown in FIG. 5A, the corresponding electromagnetic valves open the air passages to the corresponding air cylinders 36 thereby lifting the corresponding pressing followers to their operative positions. When, as is seen from FIG. 5B, a leading end of the corresponding material M is pushed into the corresponding catch device and put between the lever 52 and the upper wall of the box 45 to be held, the antenna 50 is forced to pivot to the OFF position. That is, when the materials M are held by the holder 44, the pressing followers associated with these materials M assume their rest positions as shown in FIG. 3. However, when the materials M are pulled out from the holder 44, the associated pressing followers are lifted to the operative positions.
Prior to carrying out sewing of the material M with the sewing machine 100, the following preparations is made.
That is, the leading ends of the materials M are drawn from the bobbins and passed through the corresponding guide pipes 18a to 18f, a clearance between the roller bar 22 and the pressing followers and under the antenna 40 and brought upward to the folder 44 and thrusted into the corresponding catch devices 46a, 46d, 46b, 46e, 46c and 46f of the holder 44 to be held by the same. It is to be noted that upon completion of these steps, each material M is slackened to assume a dangled position as shown by a solid line in FIG. 1. Thus, in this condition, the switches in the holder 44 assume OFF positions as shown in FIG. 5B and thus the pressing followers 30a to 30f assume their inoperative positions as shown in FIG. 3. Furthermore, due to the slackened condition of the materials M, the switch 42 (see FIG. 1) assumes its OFF position and thus the motor 24 for the roller bar 22 is deenergized.
When, for carrying out sewing, one of the materials M is pulled out from the corresponding catch device of the holder 44, the switch of the corresponding catch device is turned to its ON position and thus, the corresponding pressing follower is lifted to its operative position. The leading end of the selected material M is then brought to the work position of the sewing machine 100 and held to the position by a known holder (not shown) of the sewing machine 100. In this condition, the material M takes such a position as illustrated by a dot-dot-dash line in FIG. 1, having no effect on the antenna. That is, the material M hangs loosely or dangles. Then, the sewing machine 100 is operated to allow the needle 106 to stitch the selected material M which is moved toward the work position due to the work of the material conveyor 108. Thus, during this sewing operation, the dangling portion of the material M is gradually raised and brought into contact with the antenna 40 and finally lifts the antenna 40 up to the upper position as illustrated by a dot-dash line in FIG. 1. With this, the switch 42 is turned ON thereby energizing the motor 24 for a given period of time and thus turning the roller bar 22 by given times. Thus, the material M is newly drawn from the material drawing mechanism 20 turning the corresponding bobbin, and the material M thus becomes to take the dangling position as illustrated by the dot-dot-dash line. Of course, this drawing speed is determined very higher than a speed at which the material M is pulled by the conveyor of the sewing machine. During the sewing operation, the above-mentioned motions are repeated. Thus, no tension is applied to the selected material M during the sewing operation, and thus the product, viz., the stitched material M is prevented from suffering the undesirable creases, unlike in case of the afore-mentioned conventional sewing machine.
When the selected material M is out, another material M is pulled out from the corresponding catch device of the holder 44 and brought to the work position of the sewing machine 100 for its sewing. During this sewing, the same operation as that mentioned hereinabove is carried out in the material feeder 10. | Herein disclosed is a material feeder of a sewing machine, which comprises a first mechanism which draws a predetermined length of a narrow and long material from a bobbin when actuated, and a second mechanism which actuates the first mechanism when the length of the material drawn from the bobbin is reduced to a predetermined degree. | 3 |
This application is the national stage of PCT/EP2005/013085 filed on Dec. 7, 2005 and also claims Paris Convention priority of DE 10 2004 058 811.2 filed Dec. 7, 2004.
BACKGROUND OF THE INVENTION
The invention relates to a process for the production of polyalcohols in the form of sugar alcohols from the group of sorbitol and/or mannitol and optionally further C 6 and/or C4 and/or C 3 and/or C 2 polyols.
Sugar alcohols have numerous industrial uses. Thus, e.g. sorbitol is in particular used as a sugar substitute with a sweetening character, e.g. for dietetic foods, in the cosmetic and pharmaceutical industries and also technically in the paper and textile industries. Mannitol is e.g. also used as a sugar substitute, as a filler in the pharmaceutical industry, in the production of synthetic resins, etc. In addition, polyols with up to six carbon atoms, such as propanediols, propanetriols (glycerin) and butanediols are of great technical significance and are e.g. used in the petrochemical industry as a base substance for the production of plastics. At present such polyols are obtained from fossil fuels, particularly petroleum and after fractionation are used for plastic synthesis, such as in the production of polyurethanes. In this connection the term “polyols” also covers organic alcohols with at least two hydroxy groups.
For the production of sugar alcohols biochemical processes are known, in which sugar alcohols are produced by enzymatic treatment of the corresponding monosaccharides, but this requires very long reaction times lasting several hours or days in order to obtain a high sugar alcohol yield.
Thus, sugar alcohols are generally produced by the catalytic hydrogenation of saccharides or other carbonyl compounds with hydrogen under elevated pressure and temperature. Apart from discontinuous or batchwise performed processes in which the reaction mixture is generally stirred over several hours, continuous processes are known in which the reaction mixture is contacted in tubular reactors with the hydrogenating catalyst.
DE 1 002 304 A describes a process for the continuous hydrogenation of reducible sugars, where a fine particular nickel catalyst is suspended, mixed with an aqueous educt solution and then the mixture is continuously contacted under elevated pressure and temperature with a hydrogen flow. The educts used are in particular glucose, inverted cane sugar or lactose, which have been reacted in the aforementioned manner to sorbitol and mannitol (from glucose or inverted cane sugar) or lactosite (from lactose). However, the long reaction times necessary for a satisfactory conversion yield and the relatively limited selectivity for the production of the specific sugar alcohols are disadvantageous.
DE 960 352 B discloses a process for the production of a mixture of the sugar alcohols sorbitol and mannitol, in that an aqueous saccharose solution is hydrolyzed under elevated pressure and temperature in the presence of a nickel catalyst. However, it is disadvantageous that there is a long reaction time of 45 minutes up to several hours necessary in order to achieve a satisfactory hydrolysis reaction yield, the latter being broken off when it is completed in a range between 95% and 99%. Furthermore the selectivity with respect to specific representatives of sugar alcohols is relatively limited.
DE 199 29 368 A1 describes a process for the production of the sugar alcohol mannitol from fructose, the fructose being continuously hydrogenated in the presence of a Raney nickel catalyst at a temperature between 50° and 180° C. and a pressure between 50 and 300 bar. Fructose is used in aqueous solution and hydrogen is used as the hydrogenating agent. No information is given on the reaction time necessary for a satisfactory educt reaction, but here again the selectivity is relatively limited and in particular exclusively mannitol and sorbitol mixtures can be produced.
DE 100 65 029 A1 relates to a similar process for the production of alcohols, particularly sugar alcohols, by reacting carbonyl compounds, particularly sugars, such as sorbitol from dextrose, sorbitol and mannitol from fructose, xylite from xylose, maltite from maltose, isomaltite from isomaltose, dulcite from galactose and lactite from lactose. The educts are continuously reacted with hydrogen in the presence of a Raney catalyst based on nickel, cobalt, copper, iron, platinum, platinum, palladium or ruthenium in aqueous solution. A pressure between 30 and 450 bar and a temperature of max. 150° C. are set, in order in the case of the use of sugars as educts to ensure that the latter do not caramelize. With regards to the production of sugar alcohols, no details are given on the reaction time or selectivity and as a result of the indicated caramelization risk at temperatures above 150° C. and a multistage hydrogenation relatively long reaction times must be assumed.
DE 1 931 112 A1 describes a process for the production of mannitol and sorbitol from saccharose, in that a saccharose solution is hydrogenated with hydrogen in the presence of a hydrogenating catalyst at a temperature of approximately 160° to 190° C. and a pressure of approximately 35 to 211 bar, the process being continuously performable. Metal catalysts based on nickel are referred to as hydrogenating catalysts. The residence time is 15 minutes to 2.5 hours.
EP 773 063 A1 discloses another process for hydrogenating pure sugar alcohols using a hydrogenating catalyst in the form of Raney nickel. The process parameters indicated are e.g. temperatures of 110° to 150° C. and pressures of 40 to 200 bar. According to an embodiment crystalline glucose is hydrogenated at 130° C. and 150 bar in a continuous Raney nickel flow through a reactor, the sorbitol yield obtained being 99.3%. The use of a catalyst based on ruthenium/ruthenium oxide is not mentioned, because when performing the process in accordance with EP 773 063 A1 this allegedly leads to isomerization, decomposition and polymerization during hydrolysis.
The problem of the invention is to further develop a process for the production of polyalcohols of the aforementioned type in such a way that in the case of a high selectivity for the desired sugar alcohols, particularly sorbitol and/or mannitol, as well as optionally for further C 2 to C 6 polyols, it is economic and effective and in particular permits a simple control of the selectivity with respect to the in each case desired products.
SUMMARY OF THE INVENTION
In the case of a process of the aforementioned type, the invention solves this problem in that at least one mono-, di-, oligo- and/or polysaccharide containing a glucose and/or at least one fructose unit is continuously reacted in the presence of a hydrogenating catalyst based on ruthenium (Ru) and/or ruthenium oxide in aqueous phase, at elevated temperature and elevated pressure, with hydrogen and accompanied by the obtaining of the indicated polyalcohols, a temperature of at least 100° C., a pressure of at least 150 bar and a residence time of the reactants during catalytic hydrogenation of max. 600 s being set.
It has surprisingly been found that with such a very short residence time, i.e. in the case of a very short contact time of the indicated educts in the aqueous phase with the hydrogen in the presence of the hydrogenating catalyst based on ruthenium/ruthenium oxide of max. 600 s, preferably max. 500 s, more particularly max. 400 s, it is possible to obtain a substantially complete conversion of the educts, without any caramelization or other deterioration thereof even at a temperature in the range of or above approximately 150° C. In particularly preferred manner, the residence time is between approximately 5 s and approximately 360 s, e.g. in the range approximately 180 to approximately 240 s.
According to the invention and as a function of the desired product range, the educt used is at least one mono-, di-, oligo- and/or polysaccharide containing at least one glucose and/or fructose unit, e.g. preferably glucose and/or fructose. It is also possible to use e.g. di-, oligo- and/or polysaccharides containing at least one glucose and/or fructose unit. With the latter alternative it can be advantageous to use a di-, oligo- and/or polysaccharide containing at least one glucose unit and also at least one fructose unit, more particularly saccharose (glucose-fructose) and/or raffinose (glucose-fructose-galactose).
As will be explained hereinafter, if such an educt (e.g. glucose) is used, in the case of an appropriate control of the process parameters it is possible to obtain a selectivity of the product (e.g. sorbitol) of almost 100% and in particular through varying the temperature, pressure, short residence time and/or hydrogen/educt concentration, the selectivity for other possible products (e.g. mannitol or shorter-chain polyalcohols) can be controlled in a planned manner.
With the inventively used catalysts based on ruthenium (Ru) and/or ruthenium oxide, with the indicated, short residence times it is possible to obtain an almost complete conversion of a glucose and/or fructose-containing educt with a (as a function of the temperature and/or pressure, short residence time and/or hydrogen/educt concentration) very high selectivity of sorbitol and/or mannitol and/or shorter-chain polyols. Said catalysts based on ruthenium (Ru) and/or ruthenium oxide with regards to a complete educt conversion and an extremely high selectivity with respect to the indicated products, have proved surprisingly superior to other known hydrogenating catalysts. Mixed catalysts have proved advantageous, which contain both ruthenium and ruthenium oxide and which are preferably immobilized on at least one carrier, such as aluminium oxide (Al 2 O 3 ). A further advantage of such catalysts based on ruthenium or ruthenium oxide, e.g. compared with catalysts based on Raney nickel widely used for the production of sugar alcohols, is that their activity is maintained over a very long time period, they are not toxic and consequently can be easily handled.
With regards to the pressure during the continuous hydrogenation reaction, a pressure of at least 200 bar and preferably at least 220 bar has proved advantageous. Particular preference is given to values between approximately 220 and approximately 280 bar, particularly between approximately 230 and approximately 270 bar, e.g. around 250 bar.
Preferably a temperature between 100° and 300° C., especially between 120° and 280° C. is set and, e.g. in the case of the production of sorbitol from glucose or sorbitol and mannitol from fructose the temperature is preferably set in the range between approximately 120° and approximately 180° C., particularly between approximately 130° and approximately 170° C., e.g. around 150° C. Particularly when using an educt in the form of glucose, it is possible to obtain a selectivity for sorbitol of almost 100° C. with a virtually complete educt conversion. However, if interest is attached to obtaining a higher proportion of mannitol from glucose, the temperature is preferably increased to approximately 280° C., particularly up to approximately 250° C., e.g. up to approximately 225° C., in order to increase the selectivity for mannitol compared with that for sorbitol. When using di-, oligo- and/or polysaccharides, such as e.g. a disaccharide from a glucose unit and a fructose unit (saccharose) or a trisaccharide from a glucose, a fructose and a galactose unit (raffinose), then the preferred temperature range is approximately 175° to 225° C., preferably approximately 200° C., in order to initially completely split the educt used. On increasing the temperature to approximately 225° C. or higher, the selectivity of the inventive process can be shifted towards the C 2 , C 3 , C 4 and/or C 6 polyols, such as in particular 1,3-propanediol, glycerin (1,2,3-propanetriol), 2,3-butanediol, 1,4-butanediol, 1,2-ethanediol and optionally further partially hydrogenated sugar alcohols in smaller quantities.
BRIEF DESCRIPTION OF THE DRAWING
The sole drawing shows a preferred embodiment in accordance with the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Thus, as has already been stated, the inventive process offers the possibility to adjust the product proportions of the sugar alcohols sorbitol and mannitol or the indicated polyalcohols by varying at least one of the parameters temperature, particularly in a range between 120° and 280° C. or the aforementioned, preferred temperature ranges, pressure, residence time and/or hydrogen or educt concentration. Thus, in this way the selectivity can be controlled with a substantially complete educt conversion between approximately 100% for sorbitol, via a preponderant mannitol proportion up to shorter-chain polyalcohols, such as e.g. 1,3-propanediol, propanetriol (glycerin), 2,3-butanediol, 1,4-butanediol and ethanediol. With regards to the latter polyalcohols, it has been surprisingly found that through the inventive process product ranges for such alcohols can be obtained, which in the production of polyurethanes directly from the mixture obtained can give better results than when producing, in accordance with the prior art of polyurethanes from the corresponding product range obtained from petroleum. Thus, the graph shown in the attached drawing, reveals that the compressive stress (“comp stress” in [kPa]) in polyurethanes (curve A), produced directly by polymerization from polyols produced using the process of the invention (experiment E9 in example 3 hereinafter), as a function of the pressure (“compression” in [%]) is lower than in polyurethanes (curve B), which have been produced directly by polymerization of a commercial petroleum product containing the corresponding polyols.
Particularly for the production of sorbitol and/or mannitol, an educt concentration e.g. for the educt glucose, of between 5 and 50 mass %, particularly between 10 and 40 mass %, based on the total flow, i.e. educt including the solvent water, has proved advantageous. However, a different educt concentration can be chosen, e.g. particularly lower than 5 mass %, mainly if the other polyalcohols are to be produced.
Hereinafter the inventive process is further explained relative to embodiments, in which (tables 2, 4, 6, 8, 10, 12 and 14) the following meanings are used:
( 1 TOC: Total Organic Carbon ( 2 Yield: In each case for an educt conversion (here glucose
or fructose or saccharose) of 100%, i.e. the yield corresponds to the selectivity—all the yields are mass-specific taking account of the higher molecular weight of the hydrogenated product compared with the educt.
Example 1
Continuous production of the sugar alcohols sorbitol and/or mannitol and optionally further polyalcohols by hydrogenating glucose in aqueous solution with gaseous hydrogen in the presence of a ruthenium/ruthenium oxide mixed catalyst on aluminium oxide in the form of a fixed bed introduced into the reactor.
The monosaccharide glucose as the educt is continuously reacted in aqueous solution with gaseous hydrogen in a high quality steel tubular reactor with a length of twice 163 cm (connected in parallel) and an internal diameter of 9 mm. There is a fixed bed of a ruthenium/ruthenium oxide mixed catalyst on particles of aluminium oxide as the carrier in the tubular reactor. The experiment is performed four times, i.e. in each case twice at 150° C. and twice at 200° C., the parameters given in the following table 1 being set.
TABLE 1
Experiment
E1
E2
E3
E4
Glucose concentration of solution
30
30
30
30
used (mass % glucose in aqueous
solution)
Glucose concentration in reactor
5
5
20
20
(mass % glucose in total reactor
mass flow)
Hydrogen concentration used
100
100
25
25
(mole H 2 per mole of
glucose used)
Residence time in reactor
300
300
300
300
(seconds, s)
Temperature in reactor (° C.]
200
200
150
150
Pressure in reactor (bar)
250
250
250
250
Mass flows in reactor:
a) total mass flow [kg/h]
0.946
0.946
0.998
0.998
b) water mass flow [ml/min]
12.612
12.612
5.074
5.074
c) 30% glucose mass flow
2.368
2.368
9.996
9.996
[ml/min]
d) hydrogen mass flow [ml/min]
29.166
29.166
30.786
30.786
pH-Value
6
6
6
6
For performing experiments E1 to E4 the reactor with the hydrogenating catalyst contained therein in the form of a fixed bed is initially started up, in that the reactor is subject to a clean water flow at the reaction pressure of 250 bar and reaction temperature of 150° or 200° C. On reaching a constant water flow under the indicated pressure and temperature conditions, a hydrogen flow is supplied to the reactor in order to reduce and therefore activate the hydrogenating catalyst. On setting a constant water flow and constant hydrogen flow with the value given in table 1, the 30% glucose solution is added and the glucose mass flow indicated in table 1 is set. In the present embodiment the glucose concentration in the reactor is so set by means of dosing pumps that there is a value of 5 (experiments E1 and E2) or 20 mass % (experiments E3 and E4), based on the total mass flow added to the reactor. The residence time of 300 s or 5 min can also be set by corresponding control of the associated dosing pump, whilst taking account of the density of the medium under the conditions prevailing in the reactor and the given volume flow.
The following table 2 gives the results obtained in the experiments based on the conversion of the glucose used as the educt and the yields of the sugar alcohols sorbitol, mannitol and further polyalcohols obtained as products.
TABLE 2
Experiment
E1
E2
E3
E4
Carbon recovery rate
89
83
96
97
(TOC products 1) /TOC educts 1) in [%])
Glucose conversion [%]
100
100
100
100
Sorbitol yield 2) [%]
45
62
98
98
Mannitol yield 2) [%]
21
13
<1.5
<1.5
C 6 -alcohol yield [%]
13
8
<0.5
<0.5
C 3 -/C 4 -alcohol yield [%]
13
8
0
0
Experiments E1 to E4 show that with a residence time of 300 s, a pressure of 250 bar and a temperature of 150° C. it is possible to bring about a complete glucose conversion of 100% during the continuous catalytic hydrogenation of glucose with hydrogen in the presence of ruthenium/ruthenium oxide on aluminium oxide. There is an extremely high yield/selectivity of the sugar alcohol sorbitol of 98%, whereas for the sugar alcohol mannitol there is a low yield/selectivity of max. 1.5%. As further reaction products it was only possible to detect other C 6 alcohols in extremely small proportions of max. 0.5%.
As can also be seen, the yield of the sugar alcohol mannitol and further polyols, particularly C 3 and C 4 polyalcohols, compared with sorbitol can be increased in that the temperature is raised to a value higher than about 150° C., here 200° C. There is a sorbitol to mannitol product ratio between approximately 1:2 and approximately 1:3, without any caramelization of the glucose used due to the inventively very short residence time in the reactor. With such a temperature rise to 200° C., further C 3 , C 4 and C 6 alcohols with a total proportion of approximately 20% are obtained. The proportion of C 3 and C 4 polyalcohols is approximately 10%, based on the total product quantity and consists almost exclusively of the C 3 polyalcohol 1,3-propanediol and the C 4 -polyalcohols 2,3-butanediol and 1,4-butanediol. There is also a complete conversion of the glucose used of 100% at this temperature.
As is apparent from the following example 2, the yield of shorter-chain alcohols increases with rising temperature due to thermal decomposition and on producing sorbitol from glucose optimum process parameters are a pressure of approximately 250 bar, a temperature of approximately 150° C. and a residence time of approximately 300 s. An advantageous hydrogen concentration is between 10 and 200 mole hydrogen/mole of glucose used, preferably between approximately 20 and 150 mole hydrogen/mole of glucose used.
Example 2
Continuous production of the sugar alcohols sorbitol and mannitol, as well as further polyalcohols by hydrogenating glucose in aqueous solution with gaseous hydrogen in the presence of a ruthenium/ruthenium oxide mixed catalyst on aluminium oxide in the form of a fixed bed introduced into the reactor.
The monosaccharide glucose as the educt is continuously reacted in aqueous solution with gaseous hydrogen in a high quality steel tubular reactor with a length of twice 163 cm (connected in parallel) having an internal diameter of 9 mm in accordance with example 1. The tubular reactor contains a fixed bed of a ruthenium/ruthenium oxide mixed catalyst on particles of aluminium oxide as the carrier. The experiment is performed at higher temperatures than in example 1, namely once at 225° C. and once at 250° C., the parameters given in table 3 being set.
TABLE 3
Experiment
E5
E6
Glucose concentration of solution used
30
30
[mass.-% glucose in aqueous solution)
Glucose concentration in reactor
5
5
[mass.-% glucose in total reactor mass flow]
Hydrogen concentration used
100
100
[mole H 2 per mole of glucose used]
Residence time in reactor [seconds, s]
300
300
Temperature in reactor [° C.]
225
250
Reactor in reactor [bar]
250
250
Mass flows in reactor:
a) total mass flow [kg/h]
0.912
0.880
b) water mass flow [ml/min]
12.180
11.748
c) 30% glucose mass flow [ml/min]
2.286
2.206
d) hydrogen mass flow [ml/min]
28.166
27.168
pH-Value
6
6
As in example 1 and for performing experiments E5 and E6, the reactor containing the hydrogenating catalyst in the form of the fixed bed is started up by being supplied with a clean water flow at the reaction pressure of 250 bar and the reaction temperature of 225° or 250° C. On reaching a constant water flow under the indicated pressure and temperature conditions, a hydrogen flow is supplied to the reactor in order to reduce and therefore activate the hydrogenating catalyst. On setting a constant water flow and constant hydrogen flow with the value given in table 3, the 30% glucose solution is added and the mass glucose flow indicated in table 3 is set. In the present embodiment the glucose concentration in the reactor is set using dosing pumps in such a way that a value of 5 mass %, based on the total mass flow added to the reactor is obtained. By a corresponding control of the associated dosing pump it is possible to set the residence time of 300 or 5 min, whilst taking account of the density of the medium under the conditions prevailing in the reactor and the given volume flow.
The following table 4 summarizes the results obtained from the experiments on the basis of the conversion of the glucose used as the educt and with the yields of the sugar alcohols sorbitol, mannitol and further polyalcohols obtained as products.
TABLE 4
Experiment
E5
E6
Carbon recovery rate
76
59
(TOC products 1) /TOC educts 1) in [%])
Glucose conversion [%]
100
100
Sorbitol yield 2) [%]
35
11
Mannitol yield 2) [%]
18
12
C 6 -alcohol yield [%]
<9
<3
C 3 -/C 4 -alcohol yield [%]
<25
<34
As is apparent from table 4, the yield of further polyols, particularly C 3 and C 4 polyalcohols, compared with the sorbitol can be increased by raising the temperature to a value of approximately 225° or 250° C. Whereas at 225° C. (E5) there is a sorbitol to mannitol product ratio of approximately 1:2, without any caramelization of the glucose used due to the inventively very short residence time in the reactor, there is an increase in the proportion of C 3 and C 4 polyalcohols, which substantially completely comprise C 3 polyalcohols 1,3-propanediol and propanetriol (glycerin) and C 4 polyalcohols 2,3-butanediol and 1,4-butanediol, to approximately 25%, based on the total product quantity. The proportion of other polyalcohols, differing from sorbitol and mannitol, is below 10%.
In the case of a reaction temperature of 250° C. (E6), the sorbitol to mannitol product ratio is approximately 1:1 and in particular the sorbitol proportion decreases with increasing temperature. There is an increased C 3 and C 4 polyalcohol yield to approximately one third of the total product quantity and once again virtually exclusively 1,3-propanediol and propanetriol (glycerin), as well as 2,3-butanediol and 1,4-butanediol are obtained. The proportion of other C 6 alcohols, differing from sorbitol and mannitol, drops to approximately 3%.
Also at temperatures of 225° and 250° C., there is a complete conversion of the glucose used of 100%. An advantageous hydrogen concentration is once again approximately 10 to 200 mole hydrogen per mole of glucose used and preferably between approximately 20 and 150 mole hydrogen per mole of glucose used.
Example 3
Continuous production of the sugar alcohols sorbitol and mannitol and further polyalcohols by hydrogenating glucose in aqueous solution with gaseous hydrogen in the presence of a ruthenium/ruthenium oxide mixed catalyst on aluminium oxide in the form of a fixed bed introduced into the reactor.
The monosaccharide glucose as the educt in aqueous solution with gaseous hydrogen is continuously reacted in the high quality steel tubular reactor having a length of twice 163 cm (connected in parallel) and an internal diameter of 9 mm according to examples 1 and 2. The tubular reactor contains a fixed bed of a ruthenium/ruthenium oxide mixed catalyst on particles of aluminium oxide as the carrier. The experiment is performed at a temperature of 200° C. and a residence time of 300 s, but with different hydrogen and glucose concentrations, the parameters summarized in the following table 5 being set.
TABLE 5
Experiment
E7
E8
E9
E10
Glucose concentration in reactor
5
2
1
2
(glucose mass-% in total reactor mass flow]
Hydrogen concentration used
100
500
1000
1000
(mole H 2 /mole glucose used]
Residence time in reactor [seconds, s]
300
300
300
300
Temperature in reactor [° C.]
200
200
200
200
Pressure in reactor [bar]
250
250
250
250
According to examples 1 and 2, for performing experiments E7 to E10, the reactor is started up with the hydrogenating catalyst in the form of a fixed bed contained therein, by supplying the reactor with a flow of clean water at the reaction pressure of 250 bar and reaction temperature of 200° C. On reaching a constant water flow under the indicated pressure and temperature conditions, a hydrogen flow is supplied to the reactor in order to reduce and therefore activate the hydrogenating catalyst. On setting a constant water flow and a constant hydrogen flow with the value given in table 5 in each case, the glucose solution is added and the mass glucose flow indicated in table 5 is set. The glucose concentration in the reactor in the present embodiment is so set by using dosing pumps that there is a value between 1 and 5 mass %, based on the total mass flow added to the reactor. The residence time of 300 s or 5 min can also be set by corresponding control of the associated dosing pump, whilst taking account of the density of the medium under the conditions prevailing in the reactor and the given volume flow.
Table 6 gives the results obtained in the experiments on the basis of the yield of the glucose used as the educt and with the aid of the yields of the sugar alcohols sorbitol, mannitol and further polyalcohols obtained as products.
TABLE 6
Experiment
E7
E8
E9
E10
Carbon recovery rate
93
68
99
80
(TOC products 1) /TOC educts 1) in [%])
Glucose conversion [%]
100
100
100
100
Sorbitol yield 2) [%]
11.1
17.4
16.9
9.4
Mannitol yield 2) [%]
12.6
8.5
6.9
6.8
C 6 -alcohol yield [%]
6.4
—
—
—
C 3 -/C 4 -alcohol yield [%]
27
36
49
33
The C 3 /C 4 alcohols obtained with a yield of 49% in experiment E9 are investigated for the specific representatives thereof and the following composition was obtained (in each case expressed as the yield 2 ) of the given polyalcohol):
propanetriol (glycerin):
9.2%
1,3-propanediol:
10.6%
2,3-butanediol:
19.6%
1,4-butanediol:
9.4%.
As can be seen in table 6, as a function of the concentration of the glucose or hydrogen used in the reactor, under the indicated process parameters sorbitol and mannitol yields of up to approximately 24%, based on the total product quantity, and yields of polyols from the group propanetriol (glycerin), 1,3-propanediol, 2,3-butanediol, 1,4-butanediol and, in the case of experiment E7, further C 6 polyols (not further defined) of in all up to approximately 50%, based on the total product quantity can be obtained, by setting a hydrogen concentration higher than in example 2, here between 100 and 1000 mole/H 2 mole of glucose used. Once again there is a complete conversion of the glucose used in all experiments.
The product range of the polyalcohols according to experiment E9 was used for producing polyurethane testpieces by polymerization and the aforementioned results given in the attached drawing (curve A) were obtained.
Example 4
Continuous production of the sugar alcohols sorbitol and mannitol and further polyalcohols by hydrogenating glucose in aqueous solution with gaseous hydrogen in the presence of a ruthenium/ruthenium oxide mixed catalyst on aluminium oxide in the form of a fixed bed introduced into the reactor.
The monosaccharide glucose as the educt in aqueous solution with gaseous hydrogen is continuously reacted in the high quality steel tubular reactor with a length of twice 163 cm (connected in parallel) and with an internal diameter of 9 mm in accordance with examples 1 to 3. The tubular reactor contains a fixed bed of a ruthenium/ruthenium oxide mixed catalyst on particles of aluminium oxide as the carrier. The experiment is performed under a constant temperature of 220° C. and a constant hydrogen or glucose concentration, but with different residence times of 150 s (experiment E11) and 300 s (experiment E12), the parameters summarized in the following table 7 being set.
TABLE 7
Experiment
E11
E12
Glucose concentration in reactor
5
5
(glucose mass-% in total reactor mass flow)
Hydrogen concentration used
100
100
(mole H 2 /mole glucose used)
Residence time in reactor (seconds, s)
150
300
Temperature in reactor [° C.]
220
220
Pressure in reactor [bar]
250
250
Experiments E11 and E12 are performed in accordance with examples 1 to 3, whilst taking account of the aforementioned process parameters.
The results obtained in experiments E11 and E12 are summarized in the following table 8 with the aid of the conversion of the glucose used as the educt and the yields of the sugar alcohols sorbitol, mannitol and further polyalcohols obtained as products.
TABLE 8
Experiment
E11
E12
Carbon recovery rate
82
65
(TOC products 1) /TOC educts 1) in [%])
Glucose conversion [%]
100
100
Sorbitol yield 2) [%]
12.4
3.0
Mannitol yield 2) [%]
13.2
7.0
C 6 -alcohol yield [%]
6.3
2.8
C 3 -/C 4 -alcohol yield [%]
26
10
As can be gathered from table 8, with a reactor temperature of 220° C. the yields of further polyols, particularly the presently measured C 3 /C 4 polyols propanetriol (glycerin), 1,3-propanediol, 2,3-butanediol and 1,4-butanediol and also the not further defined C 6 polyols are not increased by lengthening the residence time under otherwise constant process parameters, but instead a doubling of the residence time from 150 to 300 s under the indicated process parameters leads to a reduction by more than half of the yields of said polyols. There is also a reduction by approximately half of the yield of the sugar alcohols sorbitol and mannitol under a substantially constant ratio of approximately 2:1 to 2.5:1. In both cases a complete conversion of the glucose used is obtained.
Example 5
Continuous production of the sugar alcohols sorbitol and mannitol, as well as further polyalcohols by hydrogenating glucose in aqueous solution with gaseous hydrogen in the presence of a ruthenium/ruthenium oxide mixed catalyst on aluminium oxide in the form of a fixed bed introduced into the reactor.
The monosaccharide glucose as the educt in aqueous solution with gaseous hydrogen is continuously reacted in the high quality steel tubular reactor with a length of twice 163 cm (connected in parallel) and an internal diameter of 9 mm in accordance with examples 1 to 4. The tubular reactor contains a fixed bed of a ruthenium/ruthenium oxide mixed catalyst on particles of aluminium oxide as the carrier. The experiment is performed four times with a residence time of 5 s and at 250°, 300°, 350° and 400° C. with a glucose concentration of 5 mass % and a hydrogen concentration of 100 mole H 2 /mole of glucose used in the reactor. The following table 9 lists the set parameters.
TABLE 9
Experiment
E13
E14
E15
E16
Glucose concentration in reactor
5
5
5
5
(Glucose mass % in total reactor mass flow)
Hydrogen concentration used
100
100
100
100
(mole H 2 mole glucose used)
Residence time in reactor [seconds, s]
5
5
5
5
Temperature in reactor [° C.]
250
300
350
400
Pressure in reactor [bar]
250
250
250
250
Experiments E13 to E16 are performed in accordance with examples 1 to 4, whilst taking account of the aforementioned process parameters.
Table 10 gives the results obtained during the experiments on the basis of the conversion of the glucose used as the educt and the yields of the sugar alcohols sorbitol, mannitol and further polyalcohols obtained as products.
TABLE 10
Experiment
E13
E14
E15
E16
Carbon recovery rate
83
80
54
20
(TOC products 1) /TOC educts 1) in [%])
Glucose conversion [%]
84
80
54
20
Sorbitol yield 2) [%]
41.8
11.0
1.0
0.1
Mannitol yield 2) [%]
6
4.2
0
0
C 2 -alcohol yield [%]
—
17.2
4.9
2.0
C 3 -/C 4 -alcohol yield [%]
13
29.5
13
6.5
Note: As the C 2 alcohol ethanediol with the yields given in table 10 was determined. As C 3 /C 4 alcohols were determined the sums of the yields given in table 10 for propanetriol (glycerin), 1,3-propanediol, 2,3-butanediol and 1,4-butanediol.
It is clear from experiments E13 to E16 that an increase in the reaction temperature to above 300° C. does not lead to a rise in the yield of shorter-chain polyols, but instead the yield thereof decreases, accompanied by a decreasing conversion of the glucose used. Despite the very short residence time of 5 s, at 250° C. (E13) there is still a sorbitol yield of approximately 42% and a mannitol yield of 6%, whilst approximately 13% polyols from the group propanetriol (glycerin), 1,3-propanediol, 2,3-butanediol and 1,4-butanediol were obtained. At 300° C. (E14) there is a sorbitol/mannitol yield of only 11 or approximately 4%, whereas the yield of the indicated polyols increases to approximately 30%. There is also a maximum ethanediol yield of approximately 17%. With higher temperatures of 350° and 400° C. (E15 and E16), there is a drastic decrease in the yields of all the desired products.
Example 6
Continuous production of the sugar alcohols sorbitol and mannitol and optionally further polyalcohols by hydrogenating fructose in aqueous solution with gaseous hydrogen in the presence of a ruthenium/ruthenium oxide mixed catalyst an aluminium oxide in the form of a fixed bed introduced into the reactor.
The monosaccharide fructose as the educt in aqueous solution with gaseous hydrogen is continuously reacted in the high quality steel tubular reactor with a length of twice 163 cm (connected in parallel), with an internal diameter of 9 mm in accordance with examples 1 to 5. The tubular reactor contains a fixed bed of a ruthenium/ruthenium oxide mixed catalyst on particles of aluminium oxide as the carrier. The experiment is performed three times in each case at 150° C. and in each case twice a fructose concentration of 20 mass % (experiments E17 and E18) and once a fructose concentration of 1 mass % (experiment E19), in each case based on the total mass flow in the reactor is set. The set parameters are listed in the following table 11.
TABLE 11
Experiment
E17
E18
E19
Fructose concentration in reactor
20
20
1
(fructose mass % in total reactor mass flow)
Hydrogen concentratioin used
25
25
100
(mole H 2 /mole fructose used)
Residence time in reactor [seconds, s]
300
300
300
Temperature in reactor [° C.]
150
150
150
Pressure in reactor [bar]
250
250
250
For performing experiments E17 to E19 the reactor with the hydrogenating catalyst contained therein in the form of a fixed bed is firstly started up by supplying the reactor with a clean water flow under the reaction pressure of 250 bar and reaction temperature of 150° C. On attaining a constant water flow under the indicated pressure and temperature conditions, a hydrogen flow is supplied to the reactor in order to reduce and therefore activate the hydrogenating catalyst. On setting a constant water flow and a constant hydrogen flow with the particular value given in table 11, the fructose solution is added and in each case the fructose mass flow indicated in table 5 is set. The fructose concentration in the reactor is so adjusted by using dosing pumps that there is a value of 20 (experiments E17 and E18) or 1 mass % (experiment E19), based on the total mass flow added to the reactor. The residence time of 300 s or 5 min can also be set by a corresponding control of the associated dosing pump, whilst taking account of the density of the medium under the conditions prevailing in the reactor and the given volume flow.
The following table 12 gives the results obtained in the experiments on the basis of the conversion of the fructose used as the educt and the yields of the sugar alcohols sorbitol, mannitol and further polyalcohols obtained as products.
TABLE 12
Experiment
E17
E18
E19
Carbon recovery rate
98
100
86.8
(TOC products 1) /TOC educts 1) in [%])
Fructose conversion [%]
100
100
100
Sorbitol yield 2) [%]
48.3
44.8
34.9
Mannitol yield 2) [%]
61.6
59.3
36.9
C 6 -alcohol yield [%]
<1
<1
<1
C 3 -/C 4 -alcohol yield [%]
<1
<1
<1
Experiments E17 to E19 show that with a residence time of 300 s, a pressure of 250 bar and a temperature of 150° C. it is possible to obtain a complete fructose conversion of 100% in the case of continuous catalytic hydrogenation of the fructose with hydrogen in the presence of ruthenium/ruthenium oxide on aluminium oxide. There are approximately constant yields or selectivities of the sugar alcohols sorbitol and mannitol in a ratio of approximately 2:3, which also remains substantially constant on raising the temperature, unlike when using glucose as the educt (cf. examples 1 ff), whereas the proportion of the further reaction products, such as C 3 , C 4 and C 6 alcohols, then rises.
With a set fructose concentration in the reactor of 1 mass % (experiment E19), there are slightly inferior mannitol and sorbitol yields compared with a fructose concentration in the reactor of 20 mass % (E17 and E18). An ideal range can be established between approximately 5 and approximately 40 mass % fructose, based on the total mass flow in the reactor.
Example 7
Continuous production of the sugar alcohols sorbitol and mannitol and optionally further polyalcohols by hydrogenating saccharose (disaccharide with a glucose unit and a fructose unit) in aqueous solution with gaseous hydrogen in the presence of a ruthenium/ruthenium oxide mixed catalyst on aluminium oxide in the form of a fixed bed introduced into the reactor.
The disaccharide saccharose as the educt in aqueous solution with gaseous hydrogen is continuously reacted in the high quality steel tubular reactor with a length of twice 163 cm (connected in parallel) and an internal diameter of 9 mm according to examples 1 to 6. The tubular reactor contains a fixed bed of a ruthenium/ruthenium oxide mixed catalyst on particles of aluminium oxide as the carrier. The experiment is performed in all three times, i.e. once at 150° C. (E20), once at 200° C. (E21) and once at 250° C. (E22), the set test parameters being summarized in the following table 13.
TABLE 13
Experiment
E20
E21
E22
Saccharose concentration in reactor
1
5
5
(Saccharose mass-% in total reactor mass flow)
Hydrogen concentration used
300
300
300
(mole H 2 /mole saccharose used)
Residence time in reactor [seconds, s]
300
300
300
Temperature in reactor [° C.]
150
200
250
Pressure in reactor [bar]
250
250
250
For performing experiments E20 to E22 the reactor with the hydrogenating catalyst contained therein in the form of a fixed bed is firstly started up by supplying a clean water flow to the reactor under the reaction pressure of 250 bar and reaction temperature of 150°, 200° or 250° C. On attaining a constant water flow under the indicated pressure and temperature conditions, a hydrogen flow is also supplied to the reactor in order to reduce and therefore activate the hydrogenating catalyst. On setting a constant water flow and constant hydrogen flow with the values given in table 13, the saccharose solution is added and the saccharose mass flow indicated in table 13 is set. The saccharose concentration in the reactor is so adjusted by dosing pumps that there is a value of 5 (E21 and E22) and 1 mass % (E20), based on the total mass flow added to the reactor. The residence time of 300 s or 5 min can also be set by a corresponding control of the associated dosing pump, whilst taking account of the density of the medium under the conditions prevailing in the reactor and the given volume flow.
The following table 14 gives the results obtained in the experiments on the basis of the conversion of the saccharose used as the educt and the yields of the sugar alcohols sorbitol and mannitol obtained as products.
TABLE 14
Experiment
E20
E21
E22
Carbon recovery rate
88
93
30
(TOC products 1) /TOC educts 1) in [%])
Saccharose conversion [%]
59
98
100
Sorbitol yield 2) [%]
49
64.5
5.1
Mannitol yield 2) [%]
18
35.5
6.2
Experiments E20 to E22 show that with a residence time of 300 s, a pressure of 250 bar and a temperature of 200° and 250° C. (E21 and E22) it is possible to obtain a substantially complete saccharose conversion of 100% accompanied by continuous catalytic hydrogenation of the saccharose with hydrogen in the presence of ruthenium/ruthenium oxide on aluminium oxide. At a temperature of 150° C. and in the case of the disaccharide used in the form of saccharose, when compared with a temperature of 200° C. there are inferior sorbitol and mannitol yields and a conversion of only roughly 60%, which is probably due to the fact that at this temperature the saccharose had not completely split into glucose and fructose. This applies both for a saccharose concentration i the reactor of 1 mass %, as in experiment E20, and for a saccharose concentration of 5 mass % in the reactor according to experiments E21 and E22 (not reproduced in detail, but in each case based on the total mass flow). An optimum parameter range for the temperature in the case of a desired product in the form of sorbitol and mannitol is between approximately 175° C. and approximately 225° C., particularly approximately 200° C. (E21).
In the indicated temperature range there are yields of the sugar alcohols sorbitol and mannitol, here in a ratio between approximately 3:1 and 2:1, the product ratio being displaced in the direction of mannitol with rising temperature. On raising the temperature to 250° C. (E22), the proportion of the here not reproduced, further reaction products, such as C 3 , C 4 and C 6 alcohols, mainly 1,3-propanediol and propanetriol (glycerin) and 2,3-butanediol and 1,4-butanediol rises significantly. The sorbitol/mannitol yields are approximately only 5.1 and 6.2%.
SUMMARY
The process according to the invention makes it possible to effectively produce the sugar alcohols sorbitol and mannitol by means of an easily handleable catalyst active over very long time periods, in the case of very short reaction times and a complete conversion of the educts, whilst ensuring easy settability and adjustability of the desired product range mannitol and sorbitol, whilst also permitting an effective production of further polyols, particularly from the group propanetriol (glycerin), 1,3-propanediol, 2,3-butanediol and 1,4-butanediol, as well as ethanediol from regrowing raw materials. Compared with polyurethanes produced from corresponding polyols obtained from petroleum/natural gas, the polyurethanes produced can have improved material characteristics. | Disclosed is a method for producing polyalcohols in the form of sugar alcohols from the group comprising sorbitol and mannitol and other optional C 2 to C 6 polyols. According to said method, a monosaccharide, disaccharide, oligosaccharide, or polysaccharide containing at least one glucose unit and/or at least one fructose unit is continuously reacted with hydrogen at an elevated temperature and at a great pressure in an aqueous phase in the presence of a hydrogenating catalyst based on ruthenium or ruthenium oxide so as to obtain the inventive polyalcohols. The minimum temperature is set at 100° C. while the minimum pressure is set at 150 bar and the maximum dwell time of the reactants during catalytic hydrogenation is set at 600 s. The inventive method is particularly suitable for producing the sugar alcohols sorbitol and/or mannitol or C 2 to C 6 polyols from glucose, fructose, or disaccharides, oligosaccharides, or polysaccharides containing glucose units or fructose units, especially saccharose, practically all the used saccharides being reacted without turning into caramel. Furthermore, the yield of said sugar alcohols or C 2 to C 6 polyols is exceptionally high while the selectivity for the desired products can be varied in a simple manner within broad boundaries. | 8 |
BACKGROUND OF THE INVENTION
It is well known to defat soybeans by extraction with solvents such as hexane and to use the defatted protein containing residue in the preparation of various food products. Soybeans defatted commercially by the presently accepted art generally contain 1 to 5 percent total lipid and a residue of bound fat, principally phospholipid, amounting to about 1 percent or more. However, it is this residual bound fat that is responsible for much of the residual off-flavor or beaniness and instability in the product. While certain of the prior art extraction procedures have been partially successful in eliminating the characteristic bitter soybean taste, the defatted residue still contains an undesirable mouth-coating factor (or substance), also described as a lard-like taste which sticks in the throat.
It additionally was discovered and disclosed in U.S. Pat. No. 3,721,569, to Steinkraus, which is hereby incorporated by reference, that the residual bound fat including the mouth-coating factor along with remaining bitterness could be removed by extraction with ethyl alcohol together with or followed by extraction with chloroform.
It is the object of the present invention to provide an improved process for producing soybean flakes which are defatted and debittered, which also removes the undesirable mouth-coating factor and produces a product with improved aqueous solubility substantially free of phospholipid.
These and other objects and advantages of the present invention will become apparent on consideration of the extractive methods more fully described in the discussion and examples which follow.
SUMMARY OF THE INVENTION
This process produces a debittered soybean product which contains a minimal fat content and which has increased water solubility utilizing a first extraction of bitter principles from soybeans with ethanol or an equivalent polar solvent followed by a succession of hexane or equivalent non-polar solvent extraction rinses to remove substantially all of the fat content of the soybeans.
DESCRIPTION OF THE INVENTION
The present invention is a method for the preparation of a defatted organoleptically bland soybean meal which unlike prior art processes, produces a product which is suitable for the preparation of aqueous extracts such as milk substitutes. In the present invention dehulled, flaked raw soybeans are extracted with ethyl alcohol (95%) or equivalent polar solvent in order to release the phospholipids and other undesirable flavor-bearing lipids. The ethanol treated soybean flakes are then extracted with a succession or plurality of hexane rinses until substantially all of the fat has been removed. The defatted soybean flakes are desolventized to remove the solvent by applying mild external heat initially at 40° to 60° C. under vacuum producing a final product at a temperature of about 40° C. The defatted soybean flakes are then pulverized to produce a product having improved aqueous solubility being substantially free of phospholipids.
The instant process in its preferred embodiments employs the following treatment steps.
Soybeans are cleaned, size-graded, exposed to circulating hot air (about 99° to 104° C.) for approximately three minutes in order to remove a small amount of moisture from the soybeans causing the cotyledons to shrivel thus facilitating removal of the hulls by passing the soybeans through a properly spaced burr mill. The hulls are subsequently removed by passing the beans through an aspirator. The soybean cotyledons are then flaked by passing the beans through a properly adjusted roller mill.
The soybean flakes are then extracted with undiluted ethanol (95%) or its equivalent. The ethanol can be applied in a stirred vat or by spraying onto the soybean flakes. A succession of 95% ethanol sprays can be used to extract substantially all of the ethanol extractable materials if so desired. The ethanol is then drained from the mixture thereby removing the ethanol soluble materials. If desired, residual ethanol can be recovered from the flakes by vacuum evaporation applying external heat at about 40° C.-60° C. (initial) with a condenser in the line. The final soybean product temperature at recovery is about 40° C.
The soybean flakes with or without residual ethanol are then extracted with a succession of extraction steps utilizing hexane or its equivalent non-polar solvent as the extraction solvent until substantially all of the fat contained in the soybeans is removed. Substantially all of the fat is herein defined as less than 0.4 percent fat (lipid) level per weight of the soybean protein; preferably less than 0.2 percent fat (lipid), most preferably less than 0.1 percent fat.
A succession or plurality of hexane extractions are utilized to increasingly reduce the fat level of the soybean flakes at each extraction step. The hexane utilized in each extraction step can be recycled from the previous extraction step. However, the final hexane rinses must be essentially fat free as initially applied in order to remove the final one percent or less of fat from the soybean flakes. The final hexane extraction liquor can then be recycled as the initial hexane extraction rinse on following batches. The hexane extraction sprays or stirred-vat treatments prior to the final hexane rinse can contain minimal amounts of fat therein consistent with commercial practice. Standard techniques for removal of fat from the hexane after each extraction step can be utilized prior to recycling if too much fat accumulates in the extraction solvent.
The removal of the final one percent of fat from the soybean flakes is dependent upon the initial application of ethanol. Although the 95% ethanol begins to exert its effect as soon as it penetrates the flaked soybeans, it is desirable that the ethanol be applied for at least 15 minutes and preferably for up to one or two hours.
To facilitate removal of residual hexane, the defatted soybean flakes can be rinsed with pure 95% ethanol after the last hexane extraction step and prior to desolventizing under vacuum.
Prior to drying, a substantial portion, such as 80 to 95 percent of the non-polar extraction solvent and extractants are removed from the solvent-protein mixture by conventional methods such as draining or centrifugal separation.
Present commercial drying processes remove retained solvent from defatted soybean products by toasting, steam-stripping or other heat treatments which decrease the water solubility of the soybean product. A soybean product having further improved water solubility is obtained in the present process by desolventizing the final defatted soybean flakes by applying mild external heat at about 40° to 60° C. (initial)-40° C. (final) under vacuum to produce a soybean product having a temperature of about 40° C. A condenser in the line enables recovery of the solvent. The resultant defatted soybean flakes are then pulverized to any desired mesh size.
Suitable polar solvents for use in the present invention in the initial extraction step include but are not limited to: lower alkanols such as methanol, ethanol, propanol, butanol or mixtures thereof. The preferred polar solvent for use in the present invention is 95% ethanol.
Suitable non-polar solvents for use in the second extraction steps for removal of residual fat include but are not limited to: medium alkane solvents such as hexane, pentane, heptane and mixtures thereof. The preferred non-polar solvent for use in the present invention is hexane.
The following example illustrates preparation of the low fat containing soybean products produced by the process of the present invention.
EXAMPLE 1
Unheated, flaked soybeans are extracted for 1 or 2 hours in a stirred vat with 95% ethanol. The ethanol and ethanol soluble products are then drained from the mixture.
The partially defatted flaked soybeans are then rinsed successively with n-hexane or an equivalent solvent containing less than one percent fat and preferably no fat. The hexane rinse is then separated, recovered and recycled to the next hexane extraction step for fat removal from the soybean flakes. These extraction steps are repeated until the fat level of the soybean flakes reaches one percent or less. A final fat-free hexane rinse is then utilized on the soybean flakes to remove substantially all of the final residual fat in the soybeans. The solvent is drained and the resultant soybean flakes can be rinsed with ethanol to facilitate removal of hexane (if desired) and the soybean flakes are vacuum dried by applying external heat at 40° -60° C. (initial)-40° C. (final product temperature). The recovered soybean flakes contain less than 0.1 percent fat and can then be pulverized to the desired mesh size and agglomerated if so desired.
The soybean protein powder recovered by the procedure of Example 1 is more than twice as soluble in hot (80° C.) water and nearly three times as soluble in hot (80° C.) dipotassium phosphate (1%) buffer compared with soxhlet extracted soybean. The product of the instant invention is especially useful as a skim milk substitute or as a base for fluid milk substitutes. | This process produces a debittered soybean product which contains a minimal fat content and which has increased water solubility utilizing a first extraction of bitter principles from soybeans with 95% ethanol or equivalent polar solvent followed by a succession of hexane or equivalent non-polar extraction rinses to remove essentially all of the fat content of the soybeans. | 0 |
BACKGROUND OF THE INVENTION
1. Field to Which Invention Relates
This invention relates to a chain of square ended valve bags, the method of making and filling the square ended valve bags and to a square ended valve bag included in the chain of square ended valve bags and removable therefrom by separating each successive bag from the chain of bags. More specifically, the invention is directed to a square ended valve bag wherein a patch or overlapped portion on the top end are partially sealed together from each seal side of the bag towards the opposite side of the bag, thereby defining valve means through which the bag may be filled from the top.
2. Description of the Prior Art
In prior bags of the square end type, the mouth of the bag has extended from one side wall to the other side wall. Other square ended bags which are also considered to be valve bags made from a film tube are Elwin David Jones, U.S. Pat. No. 3,548,722; E. D. Jones, U.S. Pat. No. 3,482,762; and John Warndell, U.S. Pat. No. 3,646,856. Jones U.S. Pat. No. 3,548,722 teaches a valve insert and a valve formed with the overlapping edges of film forming the top end of a bag. Jones U.S. Pat. No. 3,482,762 teaches the forming of a valve by constructing one of the gussetted end panels in two portions sealed together with their extremities such that they form a valve. Warndell U.S. Pat. No. 3,646,856 teaches the forming of a valve in the gussetted end by means of a valve patch secured around three sides of a slit in the gusset.
STATEMENT OF THE INVENTION
The present invention relates to a chain of square ended valve bags constructed from one or more elongated bands of sealable flexible film, and to the method of making and filling each individual square ended valve bag as well as to the construction of each individual square ended valve bag.
One of the objects of the invention is to provide a square ended valve bag which is constructed from a sealable flexible film with the corners of the bag and the perimeter of the valve sufficiently strong to withstand tearing of the seal or weld during filling, sealing and using of the bag.
Another object of the present invention is to provide a chain of square ended valve bags constructed from an elongated band of sealable flexible film, wherein each bag has a patch or overlapped portion on the top end and sealed to the top end from each seal side of the bag towards the opposite seal side thereof, and thereby defining a valve means through which the bag may be filled from the top.
A further object of the invention is to provide a chain of square ended valve bags interconnected by an elongated longitudinal portion of the band located along the back walls and top ends of all of the bags and with the seal side of each bag breakably joined to the closest seal side of the next adjacent bag in the chain.
A still further object of the invention is to construct from a single elongated band of sealable flexible film, a chain of square ended valve bags which are resistant to tear during filling thereof with a product, and with each bag in the chain successively being able to assume its square ended form during filling with a product either before or after it is separated from the next adjacent bag in the chain.
Other objects and advantages may be observed from the following description of the invention in conjunction with the several drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plan view of a chain of square ended valve bags;
FIG. 2 is a sectional view along the line 2--2 of FIG. 1;
FIG. 3 is a sectional view along the line 3--3 of FIG. 1;
FIG. 4 is a fragmentary perspective view of the top end of the bag;
FIG. 5 is a fragmentary perspective view generally along the line 5--5 of FIG. 1 and with the patch partly lifted to illustrate the valve;
FIG. 6 is a perspective view of a square ended valve bag filled with a product;
FIG. 7 is a plan view of a chain of square ended bags of modified construction;
FIG. 8 is a sectional view along the line 8--8 of FIG. 7; and
FIG. 9 is a view of a bag from the chain of bags of FIG. 7 after it has been filled.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 is a plan view showing a chain 35 of square ended valve bags 10, each having a front wall 11, a back wall 12, a top end 13, a bottom end 14, a fore seal side 15, and an aft seal side 16. The fore seal side 15 and aft seal side 16 are substantially identical to each other. As illustrated in FIG. 6, the aft seal side 16 consists of a front wall portion 17, a back wall portion 18, a top end portion 19, and a bottom end portion 20 welded or sealed together by a side seal 21.
As best illustrated in FIGS. 1 and 6, the side seal 21 includes: a center side seal leg 22 interconnecting front wall portion 17 and back wall portion 18 and extending in a plane parallel with the planes of the front wall 11 and back wall 12; a first side seal leg 23 interconnecting back wall portion 18 and top end portion 19 and extending from the terminus of center side seal leg 22 nearest to top end portion 19 to the corner intersection of top end 13 and back wall 12; a second side seal leg 24 interconnecting top end portion 19 and front wall portion 17 and extending from the terminus of center side seal leg 22 at top end portion 19 to the corner intersection of top end 13 and front wall 11; a third side seal leg 25 interconnecting front wall portion 17 and bottom end portion 20 and extending from the terminus of center side seal leg 22 at the bottom end portion 20 the corner intersection of front wall 11 and bottom end 14; and a fourth side seal leg 26 interconnecting back wall portion 18 and bottom end portion 20 and extending from the terminus of center side seal leg 22 at bottom end portion 20 to the corner intersection of bottom end 14 and back wall 12. Because the side seal on the fore seal side 15 is substantially identical to the side seal on the aft seal side 16, the specific legs thereof, and the portions being sealed together are not separately numbered in the drawings. Back wall 12 and top end 13 are sealed together along their juncture by a closing seal 27 generally in a single line in the two planes of back wall 12 and top end 13. In this instance a patch 28 is affixed around its perimeter to the top end 13. The patch 28 has an outer valve opening 29 and top end 13 has an inner valve opening 30 spaced from valve opening 29 as illustrated in FIGS. 4 and 5. The patch 28 also extends onto the top end portions 19 to reinforce the top corners at the ends of the bag. Also this puts a bend in the valve when the bag has been filled so that the valve opening 29 is on the side of the bag and valve opening 30 is on the top of the bag after it has been filled.
Bag 10 is preferably constructed from a single elongated band such as an elongated flexible film of polyethylene, nylon, polypropylene, or other polymerics which can be heat sealed or welded, adhered, cohered or otherwise secured to itself, like materials, or other film materials along the preselected lines by heat sealing, welding, gluing or other adhering means which provide structures having mechanical and property equivalents to each other so as to make side seal 21 and closing seal 27 capable of keeping a product filled square ended valve bag 10 intact during shipment and usage. The band is preferaby in the form of a flattened tube of film, but in some instances may be in the form of a relatively long film folded longitudinally upon itself in flattened tube-like fashion. The band can also be made from multi-ply or laminated films and from films containing fibrous materials such as paper, cloth, and the like which can be secured to itself along seals by hot melt gluing or other adhesives means commonly known in the industry. In addition, the exact dimensions, including thickness of film from which the walls, ends, and sides of a bag are manufactured and the dimensions of the completed bag may be preselected for the specific product and desires of the manufacturer or user of the bag, without departing from the spirit and scope of the invention.
Having thus described a completed, product filled, square ended valve bag as illustrated in FIG. 6, additional details of the method of making a chain 35 of successive bags will now be described. In FIG. 1 there is illustrated a chain 35 of bags, comprising a plurality of bags 10 interconnected by an elongatged longitudinal strip portion 36. FIG. 1 further illustrates schematically the steps in the method of making a plurality of bags 10 from a single elongated band or tube of sealable flexible film 37. Schematically the tube 37 enters FIG. 1 from the left side thereof and finished bags 10 exit from the right. In making the chain of bags, the tube 37 is first provided with a top gusset 38 and a bottom gusset 39. Top end 13 of bag 10 emanates from top gusset 38 and bottom end 14 of bag 10 emanates from bottom gusset 39. Elongated longitudinal strip portion 36 is defined by having the back half 40 of top gusset 38 extend above the front half 41 of top gusset 38. In addition, first side seal leg 23 and second side seal leg 24 may be prevented from merging and sealing or welding together and third seal leg 25 and fourth seal leg 26 may be prevented from sealing together by providing the outer surface of top gusset 38 and bottom gussst 39 with a coating or spacing means which permits welding two adjacent layers of film and prevents all four layers of film in the gusset from welding together. The preventing of the welding of first side seal leg 23 to second side seal leg 24 and third side seal leg 25 to fourth side seal leg 26 while welding side seal legs 23, 24, 25, and 26 is commonly known in the industry and not a part of this invention.
During the making of the bag 10 from tube 37 aft seal side 16 of one bag 10 is breakably connected by a perforated connection 42 to fore seal side 15 of the next adjacent or tailing bag 10, while elongated longitudinal strip portion 36 interconnects the back half 40 of gusset 38 of the two next adjacent bags 10 in the chain 35 of bags. In addition to and extending from perforated connections 42 is a notch 43 cut through bottom gusset 39 and a cut 44 extending through the back half 40 of gusset 38 and also through front half 41 of gusset 38. All cuts 44 and perforations 42 are positioned such that they will be on the outside of each finished bag 10 and so that they will not provide holes in the walls, top ends, or seal sides of bag 10.
In the chain of bags, each bag 10 has its top end 13 and bottom end 14 provided respectively with its top and bottom gusset 38 and 39, and the front wall 11 and back wall 12 are collapsed against each other.
Next, the front half of the top gusset is turned down and the front half of the bottom gusset is turned up, as seen in FIGS. 2 and 3. Inner valve opening 30 is cut in top end 13 in the top gusset and patch 28 with outer valve opening 29 therein is affixed to the top gusset with openings 29 and 30 separated from each other as illustrated in FIGS. 5 and 6. This permits easy insertion of a fill spout 49 to fill product 50 into the bag 10, as shown in FIG. 6. Also, the misalignment of the two valve openings 29 and 30 minimizes leakage of the product from the bag. If desired, the patch 28 may be formed from longitudinal strip portion 36 by cutting this strip portion 36 immediately above the closing seal 27 and affixing same around its perimeter to the top end 13 or from a separate strip of material. When the band 37 is a closed tube, then strip portion 36 becomes a tunnel, interconnecting the chain of bags. A patch 28 may optionally be added to the bottom end 14 of the bag, without a valve, to reinforce the bottom and bottom edges, as shown in FIG. 1.
In modification of FIGS. 7, 8, and 9, a bag 110 is shown, wherein side seal 121 welds all four sides of the top gusset 138 together and all four sides of the bottom gusset 139 together. This forms a unique bag 110 which has v-shaped pockets, one at each end of each side of the bag when the bag has been product filled and sealed. Thus a single side seal 121 has a top gusset welding leg 123 which welds the back wall 112 to the back half of the top end 113 to the front half of the top end 113 to the front wall 111, a bottom gusset welding leg 125 which welds the back wall 112 to the back half of the bottom end 114 to the front half of the bottom end to the front wall, and a center side seal leg 122 which welds only the back wall to the front wall. The center side seal leg 122 thus welds two plies of film while the top and bottom side seal legs 123 and 125 weld four plies of film. The patch 128 covers the v-shaped pockets and thus reinforces the bag corners. In this instance, the outer 129 and inner 130 valve openings are positioned between the side walls of the bag. Other reference numerals shown in FIGS. 7-9 are one hundred units larger than numerals for similar parts in FIGS. 1-6. As in the preferred embodiment the patch may be made from the top longitudinal strip portion 136, or from a separate sheet of material.
Although this invention has been described in preferred form with a certain degree of particularity, it is understood that the present disclosure of the preferred form has been made only by way of example and that numerous changes in the details of construction and the combination and arrangement of parts may be resorted to without departing from the spirit and scope of the invention as hereinafter claimed. | Square ended valve bags are formed from a tube-like band and in a chain with the back wall and top end of each bag partially sealed together to provide bags between the seals. Patches are placed on the top end of the bag and the patches and top ends are provided with displaced openings to provide a valve. Each bag in turn may be filled through the valve located in the top end, the bag expanding forwardly from the back wall by expanding gussets in the top and bottom ends. | 8 |
FIELD OF THE INVENTION
[0001] The present invention relates to a block LED (Light Emitting Diode) light, especially for the one that is able to assemble multiple block LED lights together as any shape; furthermore, the power connection port is able to be adopted with the LED light module, making end users be able to select different electrical power types of block LED lights by different demand purposes.
BACKGROUND OF THE INVENTION
[0002] The traditional LED (Light Emitting Diode) light is implemented by case, LED light module, and lampshade. The LED light module is implemented in the case, and the lampshade is connected with the case and covers the LED light module. Because high power LED light would generate lots of heat and thermal during operating, which would increase the temperature and this high temperature would also affect the life time of LED light, therefore, such type of LED light also contains extra thermal module in the architecture, and this thermal module connects with the LED light to increase the thermal performance.
[0003] The shape of traditional LED light is decided by the case and lampshade, the shapes of case and lampshade are fixed and the sizes can not be changed. Some LED lights use external thermal modules, and these thermal modules are integrated by different shapes of heat sinks, which shapes are also fixed and can not be changed by user's demand. Therefore, a user needs to survey and choose the most suitable LED light from different shaped and different sized LED lights by actual environment and demand, this survey process always takes lots of time and even can not discover the most suitable LED light that can meat user's demand.
[0004] Further more, the electrical power of traditional LED light is also fixed without any modification, so the LED light that is able to commit shape and size requirements could be not able to meet the demand of electrical power, which increases the difficulty of purchasing suitable LED light. One more thing, once the layout design is changed, the original LED light might be not able to meet current requirement and need to survey and purchase a new LED light again.
[0005] On the other hand, no matter using a general LED light or high power LED light, these types of traditional LED lights all use single case architecture, and the LED light module and electrical power are both integrated in the same case, for example, in the mobile LED light case, it contains both the LED light module and containing space of batteries, to provide electrical power to LED light module by batteries; for fixed LED light, it integrates LED light module and electrical power connecting port in the same case, in which the electrical power connecting port connects with the LED light module, and also connects with the electrical power socket, to electrical connect LED light module with electrical power source via this electrical power line.
[0006] In the traditional LED light, it integrates the LED light module with electrical power portion in one single case, so the LED light module and electrical power portion are not able to be separated, users are not able to choose and swap different types of electrical power by different demands, for example, in some accident conditions such as electrical power off, users are not able to take off the fixed lamps which electrical connect with electrical power source to connect with batteries directly as emergency fluorescent lights, so users have to prepare several different types of lamps to meet different demands of purposes. Although some of the traditional LED lights also be able to provide dual types of electrical power sources to choose battery source or electrical power supply, but the space of battery container in the LED light case is not able to be removed when the power supplied by electrical power source; on the other hand, the power connection port or power cord that connects with electrical power source can not be removed when the power supplied by batteries, therefore the size of traditional LED light is little bit larger.
[0007] There are several disadvantages in the technologies of traditional technology:
[0000] 1. For the traditional LED light, the shape of LED light is decided by case and lampshade, the shapes and sizes of case and lampshade can not be changed by users' demands.
2. For the traditional LED light, the power of LED light is also fixed, can not be changed by users' demands.
3. For the traditional LED light, the model spec of LED light is fixed, not easy to survey the most suitable LED light that is able to meet all demands completely.
4. For the traditional LED light, users are not able to change different types of electrical power sources by their requirements or demands;
5. For the traditional LED light, LED light just is suitable to use in one single environment, so end users have to prepare multiple lamps for different types to meet the demands of different requirements and purposes;
6. For the traditional LED light, although some of the LED lights are able to choose their power supply coming from battery or electrical power source, the battery containing space can not be removed during electrical power supplying; on the other hand, the electrical power cord or electrical power connection port can not be removed during battery supplying, therefore the space of LED light will be little larger.
[0008] Therefore, the way how to improve above disadvantages of traditional solutions to change the shape and electrical power of the LED light by user's requirement and demand, and to be able to connect with different types of electrical power sources is the major topic of the present invention.
SUMMARY OF THE INVENTION
[0009] An objective of the present invention is to provide a new and advanced block LED light, which designs two corresponding connecting portions on the surfaces of case, for example, an embedded pillar and an embedded trough, a pair of magnetic, or a magnetic and corresponding components such as a piece of metal plate, to make a block LED light be able to integrate with another block LED light with same architecture via their corresponding connection portions, to meet user's requirement and demand for assembling any quantity and any total electrical power of block LED lights together as any shape or model as user's like. On the other hand, LED light module and electrical power portion are able to be designed in two different cases, these two different cases support corresponding connection portions on their surfaces to make the LED light module be able to electricalic connect to the power source after integrating these two cases; by this way, user is able to integrate LED lights with suitable electrical power source together by their real requirement and demand.
BRIEF DESCRIPTION OF THE INVENTION
[0010] According to the present invention, the present invention provides a new and advanced block LED light, which contains the following components:
[0011] A first case;
[0012] A LED light module, which is designed in the first case;
[0013] A first connection portion, which is designed on the surface of the first case;
[0014] Ane second connection portion, which is designed on another surface of the first case;
[0015] In which, the first connection portion is corresponding to the second connection portion, making another second block LED light with the same architecture be able to connect with the second connection portion of the first block LED light by its first connection portion; and another third block LED light with the same architecture be able to connect with the second portion of the second block LED light by its first connection portion; this way would be able to assemble multiple block LED lights together.
[0016] In accordance with the block LED light, in which first connection portion contains at least one embedded pillar, and the second connection portion contains at least on embedded trough; the architecture of this embedded pillar has to be corresponding to this embedded trough; this block LED light connects with another block LED light's embedded trough (or embedded pillar) by its corresponding embedded pillar (or embedded trough).
[0017] In accordance with the block LED light, in which there is a first magnetic on the first connection portion, and there is a second magnetic on the second connection portion; this block LED light uses its first magnetic to connect with another block LED light's second magnetic, to integrate with this second block LED light.
[0018] In accordance with the block LED light, in which the electrical power port of the LED light module will extend to the first connection portion and the second connection portion, to make multiple block LED lights be able to electrical connect together by series or parallel after these multiple block LED lights integrating together.
[0019] In accordance with the block LED light, in which further contains one first conductive component, one second case, one electrical connection portion, one second conductive component, and one third connection portion; this first conductive component is designed on the surface of the first case, and electrical connects with the LED light modules; this electrical power connection portion is designed in the second case, and is designed to electrical connect with one electrical power source; this second conductive component and this third connection portion are designed on the surface of the second case, and this second conductive component is electrical connecting with the electrical power connection portion; the third connection portion on the second case and the first connection portion on the first case are corresponding, to make this first case and this second case be able to integrate together by the first connection portion of the first case and the third connection portion of the second case, and when the first connection portion of the first case integrates with the third connection portion of the second case, the first conductive component of the first case will electrical connect with the second conductive component of the second case, to make the LED light module electrical connect with power source.
[0020] In accordance with the block LED light, in which the first conductive component and the second conductive component are conductive plates.
[0021] In accordance with the block LED light, in which the electrical power source connection portion is an electrical power connection port; and the electrical power source is a grid.
[0022] In accordance with the block LED light, in which the second case contains one containing space, and the electrical power source is battery, which is contained in this contain space.
[0023] In accordance with the block LED light, in which the first connection portion of the first case contains at least one embedded pillar, and the third connection portion of the second case contains at least one embedded trough; this embedded pillar is corresponding to the embedded trough, and this first connection portion of the first case integrates with the third connection portion of the second case via embedding these embedded pillar and embedded trough.
[0024] In accordance with the block LED light, in which the first connection portion of the first case contains one first magnetic, and the third connection portion of the second case contains one second magnetic; this first connection portion of the first case integrates with the third connection portion of the second case via attracting this first magnetic and this second magnetic.
[0025] In accordance with the block LED light, in which the first connection portion of the first case contains one magnetic, and the third connection portion of the second case contains a piece of metal plate; this first connection portion of the first case integrates with the third connection portion of the second case via attracting this magnetic and this metal plate.
[0026] In accordance with the block LED light, in which the first connection portion of the first case contains one pieces of metal plate, and the third connection portion of the second case contains a magnetic; this first connection portion of the first case integrates with the third connection portion of the second case via attracting this magnetic and this metal plate.
[0027] The present invention may best be understood through the following description with reference to the accompanying drawings, in which:
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] FIG. 1 shows the system architecture diagram of the executing embodiment to the present invention of the block LED light using one single case.
[0029] FIG. 2 shows the system's bottom architecture diagram of the executing embodiment to the present invention of the block LED light using one single case.
[0030] FIG. 3 shows the assembling architecture diagram of the executing embodiment to the present invention of multiple block LED lights using one single case.
[0031] FIG. 4 shows the architecture diagram of the executing embodiment to the present invention of block LED light using grid power source.
[0032] FIG. 5 shows the architecture diagram of the executing embodiment to the present invention of block LED light using battery power source.
[0033] FIG. 6 shows the architecture diagram of the executing embodiment to the present invention of block LED light using chargeable battery power source.
[0034] FIG. 7 shows the architecture diagram of the executing embodiment to the present invention of assembling multiple LED lights.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0035] FIG. 1 shows the system architecture diagram of the executing embodiment to the present invention of the block LED light using one single case, in which contains lamp shade 11 , block LED light 12 , case 13 , embedded pillar 14 , and embedded trough 15 . The block LED light 12 of the present invention is mainly implemented by lamp shade 11 , LED light module, and case 13 . This LED light module is designed in the case 13 , lamp shade 11 connects with case 13 , and covers LED light module in the space created by the connection of lamp shade 11 and case 13 . Lamp shade 11 is produced by transparent material, therefore the light emitted by LED light module is able to transmit out through lamp shade 11 . There is a pair of corresponding connection portions on the surface of case 13 , these two corresponding connection portions can be implemented by at least one pair of corresponding embedded pillar 14 and embedded trough 15 . Therefore, the embedded trough 14 (embedded pillar 15 ) of the block LED light 12 is able to integrate with another block LED light's embedded pillar (embedded trough) which is implemented with the same architecture, to connect these two block LED lights together. Based on the architecture design of embedded pillar 14 and embedded trough 15 , multiple block LED lights 12 with the same architecture could be able to integrate together such as integrating blocks. Of course, corresponding connection portions on the surface of case 13 can also be implemented by two corresponding magnetic, or one magnetic and one piece of metal plate. So, users are able to integrate any quantities of block LED lights 12 by their requirements and demands freely, and change the total electrical power consumption, shape, and size by modifying the quantities of block LED lights 12 , to get the most suitable LED lights for real demands very easily. Furthermore, once the interior decoration is changed, these integrated LED lights can be disassembled directly in a very easy way. Even partial block LED lights 12 can be disassembled as temporarily light sources, and be assembled back after using them.
[0036] FIG. 2 shows the system's bottom architecture diagram of the executing embodiment to the present invention of the block LED light using one single case, in which contains one block LED light 12 , case 13 , embedded trough 14 , embedded pillar 15 , switch 21 , and electrical power connection port 22 . This block LED light 12 is able to use internal battery power supply, in which the batteries are implemented inside the case 13 . At the bottom of case 13 containing an electrical power connection port 22 , which is able to charge the batteries inside the case 13 via connecting the electrical power connection port 22 with electrical power source. At the bottom of case 13 also contains a switch 21 , controlling the power of LED light module is on or off.
[0037] FIG. 3 shows the assembling architecture diagram of the executing embodiment to the present invention of multiple block LED lights using one single case, in which contains block LED light 12 , embedded trough 31 , 32 , and embedded pillar 33 , 34 . Multiple block LED lights 12 are able to assemble together by integrating embedded trough 31 , 32 with embedded pillar 33 , 34 . Every electrical plug of LED light module insides every block LED light 12 is able to extend to embedded trough 31 , 32 and embedded pillar 33 , 34 , to make these above LED light modules have electrical series or parallel structure after assembling these multiple block LED lights 12 , for example, extending all positive ports of LED light modules to the embedded trough 32 and embedded pillar 34 at the upper side, and extending all negative ports of LED light modules to the embedded trough 31 and embedded pillar 33 at the bottom side, then this will be an electrical parallel structure; extending all positive ports of LED light modules to the embedded trough 31 (or 32 ), and extending all negative ports of LED light modules to the embedded pillar 33 (or 34 ), then this will be an electrical series structure.
[0038] FIG. 4 shows the architecture diagram of the executing embodiment to the present invention of block LED light using grid power source, in which contains case 41 , 42 , LED light module 411 , lamp shade 412 , connection portion 413 , 421 , conductive component 414 , 422 , and power connection port 423 . The electrical power portion of the LED light according to the present invention is also able to assemble together as block style. There is a containing space inside case 41 , and the LED light module 411 is implemented in this containing space inside case 41 . Lamp shade 412 is covered on the containing space of case 41 , and also covers LED light module 411 . There is an electrical power connection port 423 designed on the surface of case 32 , to electrical connect with grid power source via one power cord.
[0000] There is at least one surface of case 41 containing connection portion 413 and conductive component 414 , and the LED light module 411 is electrical connecting all conductive components 414 on the surface of case 41 . There is at least one surface of case 42 containing corresponding connection portion 421 and conductive component 422 , and the power connection port 423 is electrical connecting all conductive components 422 on the surface of case 42 . Based on this design of connection portions 413 , 421 and conductive components 414 , 422 , case 41 could be able to integrate with case 42 via the corresponding connection portions on the surface of case 41 's bottom and on the surface of case 42 's upper (this diagram does not figure out the connection portions on the surface of case 41 's bottom and on the surface of case 42 's upper). When the connection portions of case 41 and case 42 connect together, the conductive components of case 41 's bottom will electrical connect with the conductive components of case 42 's upper at the same time (this diagram does not figure out the conductive components on the surface of case 41 's bottom the on the surface of case 42 's upper), to make LED light module 411 be able to electrical connect with grid power source and be supplied by grid power.
[0039] FIG. 5 shows the architecture diagram of the executing embodiment to the present invention of block LED light using battery power source, in which contains case 31 , 32 , LED light module 411 , lamp shade 412 , connection portion 413 , 431 , and conductive component 414 . The present invention claims not only above LED light model which power supplies by grid power source, but also can be power supplied by other types of electrical power. Based on FIG. 5 of the present invention as an example of showing battery power supply model, there is designed an electrical power connection portion inside case 32 , and designs a containing space to contain batteries, and electrical connects with the power connection portion inside the case 43 . The upper surface of case 43 contains connection portion and conductive component that corresponds to the bottom surface of case 41 (this diagram does not figure out the corresponding connection portions and conductive components of case 41 's bottom and case 43 's upper), and the conductive component of case 43 's upper surface electrical connects with internal electrical power connection portion, to electrical connect with the batteries inside case 43 . Therefore, once case 41 connects with case 43 via the corresponding connection portions of case 41 ′ bottom and case 43 's upper, the conductive component of case 41 's bottom will be electrical connected with the conductive component of case 43 ′ upper, would make the LED light module 411 that implemented inside case 41 electrical connect with the batteries inside case 43 , to supply electrical power to LED light module 411 by batteries.
[0040] FIG. 6 shows the architecture diagram of the executing embodiment to the present invention of block LED light using chargeable battery power source, in which contains case 41 , 42 , 43 , LED light module 411 , lamp shade 412 , connection portion 413 , 421 , 431 , conductive component 414 , 422 , and electrical connection port 423 . Case 42 can also be connected with the bottom of case 43 , to make the batteries designed inside case 43 is able to electrical connect with the conductive component of case 42 's upper side via the conductive component of case 43 's bottom side, then electrical connects to grid power source through the electrical connection port 423 , and to charge the batteries inside case 43 .
[0041] In accordance with the executing embodiment to the present invention of block LED light, the conductive components 414 , 422 designed on the surfaces of case 41 , 42 , 43 could be metal conductive plates. The connection portions 413 , 42 , 431 designed on the surfaces of case 41 , 42 , 43 could be corresponding embedded pillars and embedded troughs, to assemble these cases via this embedded mechanism. The connection portions on every single surface of case 41 , 42 , 43 could be all are embedded pillars, all are embedded troughs, or both, for example, the connection portion on the surface of case 42 's upper side could be all are embedded pillars, and the connection portion on the surface of bottom side could be all are embedded troughs. Of course, connection portions 413 , 421 , 431 designed on the surfaces of case 41 , 42 , 43 can all are corresponding magnetic or combinations of magnetic and metal plates, and assembling these cases via magnetic attractive mechanism.
[0042] Therefore, in accordance with the executing embodiment to the present invention of block LED light, when users are at in-house environments, they can connect case 41 of LED light module 411 with case 42 which contains power connection port shown as FIG. 4 , supplying power to LED light module 411 by grid electrical power source; when users are at out-door environments, the same case 41 of LED light module 411 could be connected with case 43 which contains batteries shown as FIG. 5 , supplying power to LED light module 411 by batteries; once these above batteries need to be charged, users could connect to grid power source to supply electrical power to LED light module 411 and change batteries in parallel shown as FIG. 6 .
[0043] FIG. 7 shows the architecture diagram of the executing embodiment to the present invention of assembling multiple LED lights, which contains block LED light 71 , 72 , 73 . The LED light 71 according to the present invention could be able to connect with other block LED lights 72 , 73 with the same architecture via the connection portion designed on the surface of case, and after assembling these multiple block LED lights 71 , 72 , 73 , these above block LED lights will be also electrical connected together because the conductive components on the surface or every case have electrical connected already, for example, as series structure or parallel structure, and can be power supplied by single one or multiple electrical power sources.
[0044] There are several advantages of the present invention:
[0045] 1. In accordance with the executing embodiment to the present invention of block LED light, users are able to change the assembled shape and size by changing the assembled quantities and shape of block LED lights;
[0046] 2. In accordance with the executing embodiment to the present invention of block LED light, users are able to get the most suitable LED lights by tuning the assembled quantities and total power consumption of block LED lights;
[0047] 3. In accordance with the executing embodiment to the present invention of block LED light, block LED lights cab be disassembled and reassembled due to the modification of decoration; and partial block LED lights can be disassembled temporally for urgent light source requirement, which will be very convenient;
[0048] 4. In accordance with the executing embodiment to the present invention of block LED light, users are able to use different electrical power types by their requirement demands;
[0049] 5. In accordance with the executing embodiment to the present invention of block LED light, which is able to be used in every different environment, and even one single block LED light could meet different demands of usage purposes.
[0050] To sum up, in accordance with the executing embodiment to the present invention of block LED light, it is very easy and efficient to change the assembling quantities, shape, size, total power consumption, and electrical power types, is a very advance and useful solution. Even modifying the design that is described as the present invention, such as using different types of corresponding connection portions, using different shapes of cases on different types of LED light modules, or using other types of conductive components, once there is at least one pair of corresponding connection portions architecture designed on the case of LED light, and multiple of these above LED lights can be assembled as blocks, are all the claimed types that present invention covered.
[0051] Although particular embodiments of the present invention have been described in detail for purposes of illustration, various modifications and enhancements may be made without departing from the spirit and scope of the present invention. Accordingly, the present invention is not to be limited except as by the appended claims. | A block LED light comprises one first block case; one LED light module which is contained in the first block case; one first connecting portion which is designed at the surface of the first block case; one second connecting portion which is designed at another surface of the fist block case; in which the first connecting portion is corresponding to the second connecting portion, to make a second block LED light with the same architecture be able to assemble with the second connecting portion of the first block LED light by its first connecting portion. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a vacuum chuck apparatus for chucking an article like a plate, box or the like, and more particularly to a vacuum chuck apparatus which has a plurality of suction cups and in which the number of the suction cups to be actually operated is changed according the size of the article to be handled.
2. Description of the Prior Art
There has been known a vacuum chuck apparatus for chucking an article like a plate, box or the like such as a glass plate, a corrugated box or the like. The vacuum chuck apparatus has a plurality of suction cups fixed to a base member such as a chuck frame. The suction cups are pressed against a predetermined surface of the article to be chucked and the air in the suction cups is evacuated to make the pressure in the space surrounded by each suction cup and the predetermined surface of the article, whereby the article is chucked by the vacuum chuck apparatus by suction.
When such a vacuum chuck apparatus is used for transferring articles, the vacuum chuck apparatus should agree with the size of the article. However when separate vacuum chuck apparatuses are prepared for the articles of different sizes, operating cost rises and a large space is required.
Accordingly, it is preferred that a single vacuum chuck apparatus can be used for chucking articles of different sizes. An example of such a "free-size" vacuum chuck apparatus is disclosed in Japanese Utility Model Publication No. 47(1972)-12624. In the free-size vacuum chuck apparatus, a plurality of suction cups are mounted in an array on a chuck frame. The suction cups positioned in the middle of the array are fixed to the chuck frame and are constantly operated irrespective of the size of the article to be chucked, while the suction cups positioned in end portions of the array are mounted on the chuck frame to be movable between an operative position where they can chuck the article by suction together with the fixed suction cups and a retracted position above the operative position. When the size of the article to be chucked is small, the suction cups in the end portions are manually moved to the retracted position and held there by means of engagement members. When the size of the article to be chucked becomes larger, the suction cups in the retracted position are moved to the operative position by manually disengaging the engagement members. Thus, the free-size vacuum chuck apparatus can chuck articles of various sizes.
In a free-size vacuum chuck apparatus disclosed in Japanese Utility Model Publication No. 47(1972)-12625, the suction cups in the end portions of a suction cup array are mounted on the chuck frame to be movable between the operative position and the retracted position above the operative position and at the same time held by arms to be rotatable in a horizontal plane. The movable suction cups are manually swung in the horizontal plane when the size of the article to be chucked changes.
Further, in a free size vacuum chuck apparatus disclosed in Japanese Unexamined Patent Publication No. 4(1992)-41342, each suction cup is supported by a shaft and a pinion is formed on an upper part of the shaft. The pinion is in mesh with a pair of opposed rack members extending in a horizontal direction. The position of the suction cup can be manually changed by pushing up the shaft to disengage the pinion from the rack members, moving the shaft along the rack members and then engaging pinion with the rack members again. By selecting the positions of the respective suction cups according to the size of the article to be chucked, the vacuum chuck apparatus can handle articles of various sizes.
In any of the conventional free-size vacuum chuck apparatus, the suction cups are manually moved when changing the size of the articles to be chucked by the vacuum chuck apparatus, and accordingly, in a line where articles of various sizes are transferred mixed together, the line must be stopped to change the positions of the suction cups every time the size of the article changes, which greatly deteriorates the operating efficiency of the line and makes it impossible to use the vacuum chuck apparatus for an unmanned automated system.
SUMMARY OF THE INVENTION
In view of the foregoing observations and description, the primary object of the present invention is to provide a free-size vacuum chuck apparatus in which the number of the suction cups to be actually operated can be automatically changed according to the size of the article to be chucked.
In accordance with the present invention, a plurality of suction cups are arranged in an array and are supported to be movable up and down independently from each other between an operative position where each of the suction cups can attract the article by suction and a retracted position above the operative position. In one embodiment of the present invention, all the suction cups are first positioned in the operative position and some of the suction cups are automatically moved to the retracted position according to a size signal representing the size of the article to be chucked so that only the suction cups necessary for chucking the article of the size represented by the size signal remain in the operative position. In another embodiment of the present invention, all the suction cups are first positioned in the retracted position and some of the suction cups are automatically moved to the operative position according to a size signal representing the size of the article to be chucked so that only the suction cups necessary for chucking the article of the size represented by the size signal are positioned in the operative position.
That is, in accordance with the present invention, there is provided a vacuum chuck apparatus for chucking an article comprising a plurality of movable suction cups mounted on a support member to be movable up and down relative to the support member between an operative position where each of the movable suction cups can attract the article by suction and a retracted position above the operative position, drive means which move the respective movable suction cups up and down relative to the support member independently from each other between the operative position and the retracted position, an article size designating means which outputs a size signal representing the size of the article to be chucked, and a control means which controls the drive means according to the size signal from the article size designating means so that a part of the movable suction cups which are not necessary for chucking the article of the size represented by the size signal are held in the retracted position and the other suction cups are held in the operative position.
The article size designating means may be a means which detects the size of the article and outputs a size signal representing the detected size of the article, or a means which outputs a size signal representing the size of the article which is given by an operator or an external article size detecting means.
The vacuum chuck apparatus of this embodiment may have one or more fixed suction cups which are constantly held in the operative position. Such fixed suction cups are generally disposed in the middle of the array of the suction cups.
The movable suction cups may be normally held in said operative position and selectively moved to the retracted position according to the size of the article to be chucked, or may be normally held in said retracted position and selectively moved to the operative position according to the size of the article to be chucked.
The drive means may comprise a plurality of air cylinders. For example, a single acting retracting air cylinder or a double acting air cylinder may be used. When a double acting air cylinder is used, the pressure at which the suction cup is pressed against the article can be finely adjusted by controlling the pressure of air to be supplied to the air cylinder, which is particularly advantageous when the article to be chucked is fragile, apt to be scratched or soft.
In the vacuum chuck apparatus in accordance with the present invention, the movable suction cups are selectively positioned in the operative position or the retracted position automatically according to the size signal representing the size of the article. Accordingly, the vacuum chuck apparatus can be automatically adapted to various sizes, and the time and labor required for adapting the apparatus to the size of the article to be chucked can be greatly reduced, which results in great reduction of cost and great improvement of the operating efficiency.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a vacuum chuck apparatus in accordance with an embodiment of the present invention,
FIG. 2 is a side view of the vacuum chuck apparatus as seen in the direction of arrow Y in FIG. 1, and
FIG. 3 is a plan view showing the arrangement of the suction cups of the vacuum chuck apparatus shown in FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In FIGS. 1 and 2, a vacuum chuck apparatus in accordance with an embodiment of the present invention includes a support structure comprising a chuck frame 1 which is moved up and down by a lift means (not shown) and a sub frame 2 which is fixed to the chuck frame 1 to be opposed to the lower surface of the chuck frame 1 at a predetermined distance therefrom. Four suction cups 11 are fixed to the sub frame 2 by way of suction cup holders 14, and four suction cups 12 and four suction cups 13 are mounted on the chuck frame 1 to surround the four suction cups 11. The suction cups 12 and 13 are mounted on the chuck frame 1 to be movable up and down and the suction cups 12 are positioned nearer to the center of the chuck frame 1 than the suction cups 13. The suction cups 12 will be referred to as "the inner movable suction cups 12" and the suction cups 13 will be referred to as "the outer movable suction cups 13" while the suction cups 11 will be referred to as "the fixed suction cups 11", hereinbelow.
Each of the fixed suction cups 11 is fixed to the sub frame 2 with its attracting surface faced downward and connected to a vacuum pump 40 through vacuum hoses 35 and 36 and an electromagnetic valve 37. The vacuum hoses 35 for a pair of fixed suction cups 11 which are diagonally opposed to each other (See FIG. 3) are connected to one vacuum hose 36. The electromagnetic valve 37 is opened and closed by a predetermined control signal.
The movable suction cups 12 and 13 are mounted on the chuck frame 1 by way of single acting retracting air cylinders 22 and 21 with their attracting surface faced downward. The movable suction cups 12 and 13 are normally held in the operative position shown by the solid line in FIG. 2, and are lifted to the retracted position shown by the dotted line when the size of the article 100 to be chucked is small and they need not be operated. The air cylinders 22 and 21 lift the movable suction cups 12 and 13 to the retracted position under the pressure of air supplied from an air pump 60.
The air cylinders 22 for the inner movable suction cups 12 and the air cylinders 21 for the outer movable suction cups 13 are connected to the air pump 60 through separate air lines. That is, each of the air cylinders 22 for the inner movable suction cups 12 is connected to a common air pipe 53a through a discrete air hose 52a, and the common air pipe 53a is connected to the air pump 60 through air hoses 54a and 56a. An electromagnetic valve 55a is provided between the air hoses 54a and 56a. Each of the air cylinders 21 for the outer movable suction cups 13 is connected to a common air pipe 53b through a discrete air hose 52b, and the common air pipe 53b is connected to the air pump 60 through air hoses 54b and 56b. An electromagnetic valve 55b is provided between the air hoses 54b and 56b. The electromagnetic valves 55a and 55b are separately opened and closed by a control signal.
Each of the inner movable suction cups 12 is connected to the vacuum pump 40 through a discrete vacuum hose 32a, a common air pipe 33a and a vacuum hose 34a and an electromagnetic valve 39a is provided between the vacuum hose 34a and the vacuum pump 40. Each of the outer movable suction cups 13 is connected to the vacuum pump 40 through a discrete vacuum hose 32b, a common air pipe 33b and a vacuum hose 34b and an electromagnetic valve 39b is provided between the vacuum hose 34b and the vacuum pump 40. The electromagnetic valves 39a and 39b are separately opened and closed by a control signal.
The vacuum chuck apparatus is further provided with an article size designating means 80 which outputs a size signal S representing the size of the article 100 to be chucked and a controller 70 which outputs the control signals for selectively opening and closing the electromagnetic valves 55a, 55b, 37, 39a and 39b according to the size signal S.
The article size designating means 80 may be a means which detects the size of the article 100 and outputs a size signal S representing the detected size of the article 100, or a means which outputs a size signal S representing the size of the article 100 which is given by an operator or an external article size detecting means.
Basically the vacuum chuck apparatus of this embodiment operates in the following manner.
That is, the chuck frame 1 is moved downward until the suction cups in the operative position (11; 11, 12 and 13; 11 and 12; or 11 and 13) are brought into abutment against the upper surface of the article 100 and then further moved downward by about 10 mm (buffer stroke) to press the suction cups against the upper surface of the article 100.
In this state, the electromagnetic valves for supplying suction to the suction cups in the operative position are opened and suction is supplied to the suction cups, whereby the article 100 is attracted by the suction cups by suction. When the chuck frame 1 is lifted in this state, the article 100 is also lifted.
When the article 100 is to be put on a place, the chuck frame 1 is moved downward to position the article 100 on the place and the electromagnetic valves for supplying suction to the suction cups in the operative position are closed to stop supply of suction to the suction cups. Thereafter air is introduced into the suction cups through vent holes (not shown) and the article 100 is released from the suction cups.
Since the fixed suction cups 11 are constantly held in the operative position, they are normally operated irrespective of the size of the article 100.
According to the size of the article 100, the vacuum chuck apparatus of this embodiment is controlled in the following manner.
When the size of the article 100 is as indicated at d in FIG. 3, the article size designating means 80 outputs a size signal S d representing the size d and the size signal S d is input into the controller 70. When the size signal S d is input into the controller 70, the controller 70 causes all the suction cups 11, 12 and 13 to operate. That is, the controller 70 outputs the control signals to close the electromagnetic valves 55a and 55b so that the air cylinders 22 and 21 for the inner movable suction cups 12 and the outer movable suction cups 13 are not supplied with air from the air pump 60, whereby the air cylinders 22 and 21 are all kept stretched and the suction cups 12 and 13 are all held in the operative position. In the operative position, all the suction cups 11 to 13 are positioned in a horizontal plane.
In this state, the chuck frame 1 is moved downward and the suction cups 11 to 13 are all pressed against the upper surface of the article 100, and then the controller 70 outputs the control signals to open the electromagnetic valves 37, 39a and 39b so that all the suction cups 11 to 13 are supplied with suction from the vacuum pump 40, whereby the article 100 is attracted by the suction cups 11 to 13 by suction. When the article 100 is to be released, the controller 70 causes the electromagnetic valves 37, 39a and 39b to close so that supply of suction to the suction cups 11 to 13 is cut.
When the size of the article 100 is as indicated at c in FIG. 3, the article size designating means 80 outputs a size signal S c representing the size c and the size signal S c is input into the controller 70. When the size signal S c is input into the controller 70, the controller 70 causes the inner movable suction cups 12 which are not necessary for chucking the article 100 of the size c to move to the retracted position. That is, the controller 70 outputs the control signal to open the electromagnetic valve 55a so that the air cylinders 22 for the inner movable suction cups 12 are supplied with air from the air pump 60 with the electromagnetic valve 55b kept closed, whereby the air cylinders 22 for the inner movable suction cups 12 are caused to contract and the inner movable suction cups 12 are lifted to the retracted position while the air cylinders 21 for the outer movable suction cups 13 are kept stretched and the outer movable suction cups 13 are kept in the operative position.
In this state, the chuck frame 1 is moved downward and the suction cups 11 and 13 are pressed against the upper surface of the article 100, and then the controller 70 outputs the control signals to open the electromagnetic valves 37 and 39b and to keep the electromagnetic valve 39a closed so that the suction cups 11 and 13 are supplied with suction from the vacuum pump 40, whereby the article 100 is attracted by the suction cups 11 and 13 by suction. When the article 100 is to be released, the controller 70 causes the electromagnetic valves 37 and 39b to close so that supply of suction to the suction cups 11 and 13 is cut.
When the size of the article 100 is as indicated at b in FIG. 3, the article size designating means 80 outputs a size signal S b representing the size b and the size signal S b is input into the controller 70. When the size signal S b is input into the controller 70, the controller 70 causes the outer movable suction cups 13 which are not necessary for chucking the article 100 of the size b to move to the retracted position. That is, the controller 70 outputs the control signal to open the electromagnetic valve 55b so that the air cylinders 21 for the outer movable suction cups 13 are supplied with air from the air pump 60 with the electromagnetic valve 55a kept closed, whereby the air cylinders 21 for the outer movable suction cups 13 are caused to contract and the outer movable suction cups 13 are lifted to the retracted position while the air cylinders 22 for the inner movable suction cups 12 are kept stretched and the inner movable suction cups 12 are kept in the operative position.
In this state, the chuck frame 1 is moved downward and the suction cups 11 and 12 are pressed against the upper surface of the article 100, and then the controller 70 outputs the control signals to open the electromagnetic valves 37 and 39a and to keep the electromagnetic valve 39b closed so that the suction cups 11 and 12 are supplied with suction from the vacuum pump 40, whereby the article 100 is attracted by the suction cups 11 and 12 by suction. When the article 100 is to be released, the controller 70 causes the electromagnetic valves 37 and 39a to close so that supply of suction to the suction cups 11 and 12 is cut.
When the size of the article 100 is as indicated at a in FIG. 3, the article size designating means 80 outputs a size signal S a representing the size a and the size signal S a is input into the controller 70. When the size signal S a is input into the controller 70, the controller 70 causes the inner and outer movable suction cups 12 and 13 which are not necessary for chucking the article 100 of the size b to move to the retracted position. That is, the controller 70 outputs the control signals to open the electromagnetic valve 55a and 55b so that the air cylinders 22 and 21 for the inner and outer movable suction cups 12 and 13 are supplied with air from the air pump 60, whereby the air cylinders 22 and 21 for the inner and outer movable suction cups 12 and 13 are caused to contract and the inner and outer movable suction cups 13 are lifted to the retracted position.
In this state, the chuck frame 1 is moved downward and only the fixed suction cups 11 are pressed against the upper surface of the article 100, and then the controller 70 outputs the control signals to open the electromagnetic valves 37 and to keep the electromagnetic valves 39a and 39b closed so that the fixed suction cups 11 are supplied with suction from the vacuum pump 40, whereby the article 100 is attracted by the fixed suction cups 11 by suction. When the article 100 is to be released, the controller 70 causes the electromagnetic valves 37 to close so that supply of suction to the fixed suction cups 11 is cut.
EXAMPLE
A vacuum chuck apparatus shown in FIG. 1 was made in the following specifications. That is, the fixed suction cups 11 were of urethane rubber and 80 mm in diameter. The inner and outer suction cups 12 and 13 were of urethane rubber and 50 mm in diameter. The air cylinders 21 and 22 were 20 mm in diameter and 25 mm in stroke. The vacuum chuck apparatus was housed in a casing of 500 mm×450 mm×150 mm made by welding thin iron plates and was about 35 kg in weight.
Using the vacuum chuck apparatus, corrugated boxes containing therein photosensitive materials were handled. The sizes and the weights of the corrugated boxes were as follows.
(a) 100 mm×150 mm×150 mm, 8 kg
(b) 210 mm×270 mm×170 mm, 10 kg
(c) 300 mm×440 mm×300 mm, 15 kg
(d) 500 mm×600 mm×200 mm, 20 kg
An AC power source of the commercial power frequency was used and an air compressor which could output 5 kg/cm 2 air pressure was used. The size switching was effected within 1 second. The attracting force obtained solely by the fixed suction cups 11 was 40 kg (vacuum pressure), that obtained by the fixed suction cups 11 and the inner movable suction cups 12 was 52 kg and that obtained by the fixed suction cups 11 and the inner and outer movable suction cups 12 and 13 was 64 kg.
The maximum load of the vacuum chuck apparatus was 60 kg, the maximum lifting speed was 1000 mm/sec, and the maximum rotational speed about the vertical axis and the horizontal axis was 2.44 rad/sec (140° C./sec). The article positioning accuracy of the apparatus was within plus or minus 1 mm.
As can be understood from the description above, in the vacuum chuck apparatus of this embodiment, the movable suction cups 12 and 13 are selectively positioned in the operative position or the retracted position automatically according to the size signal representing the size of the article. Accordingly the vacuum chuck apparatus can be automatically adapted to various sizes, and the time and labor required for adapting the apparatus to the size of the article to be chucked can be greatly reduced, which results in great reduction of cost and great improvement of the operating efficiency.
Though, in the embodiment described above, a single acting retracting air cylinder is used as the drive means for moving the movable suction cup between the operative position and the retracted position, other various drive means may be used. For example, a double acting air cylinder may be used and hydraulic or mechanical drive means may be used. When a double acting air cylinder is used, the pressure at which the suction cup is pressed against the article can be finely adjusted by controlling the pressure of air to be supplied to the air cylinder, which is particularly advantageous when the article to be chucked is fragile, apt to be scratched or soft. | In a vacuum chuck apparatus for chucking an article, a plurality of movable suction cups are mounted on a support member to be movable up and down relative to the support member between an operative position where each of the movable suction cups can attract the article by suction and a retracted position above the operative position. A plurality of air cylinders move the respective suction cups independently from each other between the operative position and the retracted position. An article size designating circuit outputs a size signal representing the size of the article to be chucked, and a controller controls the air cylinders according to the size signal so that a part of the movable suction cups which are not necessary for chucking the article of the size represented by the size signal are held in the retracted position and the other suction cups are held in the operative position. | 1 |
TECHNICAL FIELD
The present invention relates to process for producing high pressure hydrogen gas.
BACKGROUND
Hydrogen is very important feedstock for many chemical and petrochemical processes. It is commonly produced using Steam Methane Reforming, Partial Oxidation, Auto thermal Reforming, and Gasification etc. Carbonaceous feedstock like natural gas, coal, biomass etc. along with oxidizing agent like steam or oxygen undergoes reforming reaction to produce synthesis gas (syngas). Syngas is a mixture of hydrogen, carbon monoxide, carbon dioxide, water and un-reacted methane. Reforming reaction is highly endothermic occurring at very high temperatures of 800-1300 C and high pressures of 20-80 bar. The reforming reaction can be catalytic or non-catalytic process. Excess steam is produced in the process of cooling down syngas and flue gas. The heat required for the highly endothermic reforming reaction is provided by combustion of the carbonaceous feedstock and carbon containing off-gas. The combustion process is associated with generating greenhouse gas, carbon dioxide (CO 2 ) emissions. Syngas from reformer is further sent to water gas shift reactor to produce additional hydrogen from carbon monoxide. Water gas shift reaction produce additional carbon dioxide during the reaction. Syngas rich in hydrogen from water gas shift is further purified in a Pressure Swing Adsorption (PSA) process to produce pure hydrogen and PSA off-gas which is further used as fuel. Hydrogen production is associated with large amounts of carbon dioxide emissions. With current advancement in greenhouse gas regulations, research is underway to capture carbon dioxide from conventional hydrogen plants or reduce emissions from hydrogen plants.
Methane can be converted to hydrogen using conventional hydrogen production methods at equilibrium conditions. However, very high temperatures >900° C. and low pressures <30 bar are needed in order to achieve high methane conversions >85%. In order to provide high temperatures required for the reaction the amount of fuel consumed is very high emitting large amounts of carbon dioxide. The use of membrane reactor includes reaction and separation in the same unit allowing methane conversion higher than equilibrium conversion rate at much lower temperatures.
Membrane reactors have been used beneficially to produce hydrogen with higher methane conversion at low temperatures and simultaneously produce carbon dioxide rich stream on the retentate side with ease of CO 2 capture. Membranes addition inside the reactor enables the reforming and water gas shift reaction to proceed at rates higher than equilibrium. However, one of the main disadvantages of using membrane reactors is hydrogen production at low pressure <3 bar. The cost associated with compressing hydrogen product is very high and increases the overall cost of membrane reactor.
SUMMARY
This process includes separating hydrogen from a hydrogen containing stream in at least two sequential palladium membrane purification zones, wherein each purification zone has a permeate side, wherein the permeate side pressure of purification zones are not the same.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 is a schematic representation of one embodiment of the present invention.
FIG. 2 is a schematic representation of one embodiment of the present invention.
DESCRIPTION OF PREFERRED EMBODIMENTS
Illustrative embodiments of the invention are described below. While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof have been shown by way of example in the drawings and are herein described in detail. It should be understood, however, that the description herein of specific embodiments is not intended to limit the invention to the particular forms disclosed, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims.
It will of course be appreciated that in the development of any such actual embodiment, numerous implementation-specific decisions must be made to achieve the developer's specific goals, such as compliance with system-related and business-related constraints, which will vary from one implementation to another. Moreover, it will be appreciated that such a development effort might be complex and time-consuming, but would nevertheless be a routine undertaking for those of ordinary skill in the art having the benefit of this disclosure.
The present invention deals with using the hydrogen selective membrane in stages on syngas or hydrogen containing gas downstream of a steam methane reformer, pre-reformer, gasifier or any other unit where hydrogen mixture is produced. The flux of hydrogen across the membrane depends on its partial pressure on shell side and permeates side. Hydrogen can permeate through the membrane as long as the partial pressure of hydrogen on shell side is higher than the permeate side. There will be no additional hydrogen permeation with increase in membrane surface area if the partial pressure of hydrogen is same on shell side and permeate side. The concept of staged palladium membrane is to produce hydrogen at high pressure followed by medium and low pressure. This will allow to recover a portion of hydrogen at high pressure as opposed to entire hydrogen stream at low pressure <3 bar. The goal is reduce the compression cost of hydrogen product. The stages of hydrogen selective membrane can be without catalyst in order to avoid methanation reaction or with water gas shift catalyst in order to complete the CO conversion to hydrogen. The last stage with low pressure hydrogen production can be with catalyst in order to complete methane conversion and recover remaining hydrogen. The catalytic reaction stage can be added in between the stages in order to increase the partial pressure of hydrogen in syngas and produce additional hydrogen at high pressure. Sweep gas such as steam can be used in order to increase the pressure of hydrogen from stages. Steam can also be added on the process gas side where water gas shift reaction is desired with WGS catalyst.
Hydrogen selective membrane reactors have been used to undergo reforming or water gas shift reaction along with simultaneous hydrogen separation. Palladium or its alloys are permeable to H2 but not to other gases. When H 2 contacts the Pd membrane, the hydrogen molecule is adsorbed on the surface where it dissociates and hydrogen atoms diffuse into the membrane Thus H 2 can selectively pass from one surrounding atmosphere through the palladium membrane. The selectively separated hydrogen atoms then re-combine into H 2 gas on the opposite side of the membrane. The difference in hydrogen partial pressure drives the permeation of hydrogen through the membrane. At a specific point on the membrane, the hydrogen flow rate is equal to the permeance multiplied by the membrane surface area multiplied by the difference of the square root of the H 2 feed partial pressure and the square root of the H2 permeate partial pressure, as shown by the following formula:
Q=P·S· ( P H2,feed 1/2 −P H2,permeate 1/2 )
Where Q is the hydrogen molar flow rate, P, the permeance, S the membrane surface area, P H2,feed the hydrogen partial pressure in the feed, and P H2,permeate the hydrogen partial pressure in the permeate. Permeance increases with increasing operating temperature.
Palladium membrane can be manufactured using several different techniques. US 20100132546 and US2009277331A describe the composite gas separation module including the porous metal substrate, intermediate layer and a dense gas selective metallic membrane. The intermediate layer is used to prevent porous metal support diffusion into the dense metallic membranes at operating conditions. U.S. Pat. No. 5,366,712A describes the use of porous ceramic material support for hydrogen selective membrane.
Hydrogen selective membrane can be manufactured from various different alloys including but not limited to palladium, silver, gold, platinum, yttrium, ruthenium, copper etc. The thickness of hydrogen selective dense metal layer can vary from 3 microns to 20 microns preferably from 5 micron to 10 micron. The operating temperature of hydrogen selective membrane can vary from 300° C. to 700° C. preferably from 450° C. to 550° C. The operating pressure of hydrogen selective membrane can vary from 10 bar to 90 bar.
Membrane reactors have the advantage of driving the reaction rates beyond chemical equilibrium at lower temperatures and enable gas separation in the same unit. In conventional SMR, the reaction takes place in Steam Methane Reformer (SMR) followed by Water Gas Shift (WGS) reactor and the hydrogen purification occurs in Pressure Swing Adsorption (PSA) unit. Membrane reformers can replace the SMR, WGS and PSA in a single unit. However, the hydrogen purity from membrane reformers is still questionable and a small Thermal Swing Adsorption (TSA) unit or a small PSA unit may still be needed to achieve very high hydrogen purity required by customers.
With current regulations on carbon dioxide emissions it is important to capture CO 2 from the hydrogen plants. In a conventional SMR unit carbon dioxide can be captured from syngas or PSA off-gas. The CO 2 content in PSA off-gas is less than 50% and is available at low pressure (<2 bar). The CO 2 content in syngas is less than 25% and is available at syngas pressure 20-30 bar. In the case of a membrane reformer the shell-side gas is rich in CO 2 with more than 80% concentration on dry basis and is available at high pressure (feed pressure) 30-40 bar. It is advantageous to capture CO 2 from membrane reformer as it is available at higher content and high pressure making the capture process much simpler than the capture process from conventional SMR. However, the hydrogen product on the permeate side is at low pressure <10 bar mostly <3 bar. Hydrogen product cannot be produced at high pressure in the catalytic membrane reactor because the hydrogen partial pressure always remain low on the shell side and it permeates on the permeate side as soon as it is formed. Hydrogen product is mostly needed at high pressure >20-40 bar for most of the chemical processes. The cost of hydrogen product compression from 1-10 bar to 20-40 bar requires multiple compression stages and increases the overall cost of hydrogen production making the use of membrane reformers uneconomical. Another disadvantage of membrane reformers with catalyst and membrane together is that the reaction kinetics and hydrogen permeability rate is very crucial. If the reaction kinetics is too fast catalyst will act intermittently with surges waiting for the hydrogen to permeate through the membrane underutilizing the catalyst area. If the hydrogen permeation is too fast the flux of hydrogen will be low as the hydrogen partial pressure on the shell side will be low underutilizing the membrane area. The material compatibility of catalyst with membrane can also be an issue. In few cases catalyst are known to scratch the membrane surface causing defects on the membrane. In order to better utilize the catalyst or membrane area and avoid compatibility issues staged process has been proposed in the past. The concept of staged membrane process has been described in patent application US2008/0311013A1 where the catalytic reactor is separated from membranes in order to better utilize the catalyst and membrane area. However the proposed solutions produce hydrogen at low pressure on the permeate side. All the permeate streams are mixed from the stages to deliver hydrogen at low pressure.
The current invention deals with the use of staged membrane process with hydrogen product withdrawal at different pressures in order to reduce cost of hydrogen product compression. The staged membrane process can be used on a mixture of gases with hydrogen from refinery or any other chemical processes. The proposed solution can be used on syngas obtained from Steam Methane Reformer. The SMR can operate at 650-950° C. and 20-45 bar pressure in order to produce hydrogen at partial pressure from 7 bar to 22 bar. The proposed solution can be used on syngas produced from pre-reformer at 500-700 C at 30-45 bar in order to produce hydrogen at 3 to 13 bar partial pressure.
Gasifiers using coal, biomass or other carbon containing feed stock can also be used at 900-1400 C and 20-80 bar in order to produce hydrogen at 8 to 30 bar partial pressure. The high partial pressure of hydrogen is favorable to produce hydrogen at high pressure. Syngas with high hydrogen partial pressure can also be produced using high pressure partial oxidation or auto thermal reforming. The staged membrane process can be used to produce hydrogen at different pressures in order to reduce the hydrogen product compression cost. The number of stages can vary from 2 to 6. Each staged membrane process unit can be with or without catalyst. Water gas shift catalyst may be used in order to complete the CO conversion to hydrogen and increase the partial pressure of hydrogen in syngas. Reforming or pre-reforming catalyst may not be used in the first stage because of potential reverse methanation reaction. Reforming or pre-reforming catalyst can be added in a stage where hydrogen partial pressure is low and methanation reaction is not favorable in order to complete the methane conversion and produce additional hydrogen. Hydrogen product from different stages with same pressure can be mixed and directed to a compression stage.
For example, the staged membrane process can be used as shown in FIG. 1 in order to produce hydrogen at high pressure followed by medium and low pressure. This allows reducing the compression energy of hydrogen product and overall compression cost of hydrogen. The hydrogen permeate from first stage can be produced at 5 bar to 30 bar. The hydrogen permeate from second stage can be produced at 3 bar to 20 bar. The hydrogen permeate from third stage can be produced from 1 bar to 10 bar. Multi-stage reforming, pre-reforming or gasification can also be used by recycling the hydrogen depleted syngas to the second stage of reforming to increase partial pressure of hydrogen.
Turning to FIG. 1 , syngas 101 generated from a pre-reformer, reformer or gasifier (not shown) enters first stage 102 Pd membrane. This generates high pressure hydrogen permeate stream 103 , and retentate stream 104 . Retentate stream 104 then enters second stage 105 Pd membrane. This generates medium pressure hydrogen permeate stream 106 , and retentate stream 107 . Retentate stream 107 then enters third stage 108 Pd membrane. This generates low pressure hydrogen permeate stream 109 , and carbon dioxide rich retentate stream 110 .
Low pressure hydrogen permeate stream 109 may be sent to first compressor 111 .
This produces a second medium pressure hydrogen stream 112 , the pressure of which is approximately the same as that of medium pressure hydrogen permeate stream 106 . Medium pressure hydrogen permeate stream 106 and medium pressure hydrogen stream 112 may be combined and then may be sent to second compressor 113 . This produces a second high pressure hydrogen stream 114 , the pressure of which is approximately the same as that of high pressure permeate stream 103 . High pressure hydrogen permeate stream 103 and high pressure hydrogen stream 114 may be combined and then may be sent to booster 115 to further increase the pressure of the stream. Boosted hydrogen stream 116 may then be used in subsequent processes (not shown).
This hydrogen rich syngas can be sent to staged membrane process in order to recover additional hydrogen at high pressure as shown in FIG. 2 . Sweep gas 123 such as steam can be used in the stages in order to increase the permeate pressure of the hydrogen. The permeate gas which is a mixture of hydrogen and steam can be further cooled down and condensed in order to separate hydrogen from steam.
In order to minimize ambiguity, the numbering convention is maintained for all figures. Turning to FIG. 2 , syngas 101 generated from a pre-reformer, reformer or gasifier 117 enters first stage 102 Pd membrane. This generates high pressure hydrogen permeate stream 103 , and retentate stream 104 . Retentate stream 104 then enters second stage 105 Pd membrane. This generates medium pressure hydrogen permeate stream 106 , and retentate stream 107 . Retentate stream 107 is returned to a second stage 119 of pre-reformer, reformer or gasifier 117 . Second syngas stream 120 then enters third stage 108 Pd membrane. This generates second high pressure hydrogen permeate stream 122 , and retentate stream 121 . Retentate stream 121 then enters fourth stage 110 Pd membrane. This generates low pressure hydrogen permeate stream 109 , and carbon dioxide rich retentate stream 118 .
Low pressure hydrogen permeate stream 109 may be sent to first compressor 111 . This produces a second medium pressure hydrogen stream 112 , the pressure of which is approximately the same as that of medium pressure hydrogen permeate stream 106 . Medium pressure hydrogen permeate stream 106 and medium pressure hydrogen stream 112 may be combined and then may be sent to second compressor 113 . This produces a third high pressure hydrogen stream 114 , the pressure of which is approximately the same as that of high pressure permeate stream 103 and second high pressure hydrogen permeate stream 122 . High pressure hydrogen permeate stream 103 , second high pressure permeate steam 122 , and high pressure hydrogen stream 114 may be combined and then may be sent to booster 115 to further increase the pressure of the stream. Boosted hydrogen stream 116 may then be used in subsequent processes (not shown). The palladium membrane may also be catalytic. Typically, the last stage is catalytic in order to increase the methane conversion ( 108 in FIGS. 1 and 110 in FIG. 2 ).
The TSA system can be used to completely dry hydrogen gas. TSA or PSA unit can be used on hydrogen product gas in order to remove any trace impurities like carbon monoxide, carbon dioxide, methane or water and produce high purity hydrogen. The carbon dioxide rich stream from the shell side of membrane can be further purified using cryogenic process or any other purification process. The pure carbon dioxide can be captured and used for enhanced oil recovery or sent for geological sequestration, deep saline aquifer etc. | A hydrogen purification process is provided. This process includes separating hydrogen from a hydrogen containing stream in at least two sequential palladium membrane purification zones, wherein each purification zone has a permeate side, wherein the permeate side pressure of purification zones are not the same. | 8 |
BACKGROUND OF THE INVENTION
This invention relates to a single-reel type tape cartridge for use with magnetic recording-reproducing apparatus and, more particularly, to improvements in the tape leader of a tape cartridge of this type.
Single-reel type tape cartridges are extensively used in computer backup and other data storage applications for safekeeping. With a tape cartridge of this type, a leader tape or leader member attached to the outer end of a magnetic tape is drawn out by drawing-out means provided in a magnetic recording-reproducing apparatus (hereinafter referred to as a “recorder”) or drive, the tape is led through passages in the recorder, and the tape end is fixed to the hub of another reel normally held within the recorder. On conclusion of recording or playback operation the tape is driven backward and withdrawn into the cartridge, until the leader tape is reset in the original position in the cartridge.
Typical of leader members for conventional single-reel type tape cartridges is one (disclosed, e.g., in Japanese Patent Application Kokai No. 58-169380) which comprises a pin, block, etc. secured to a tape end to be caught by a tape drawing-out member of a recorder. Another type uses a leader tape of relatively tough, elastic material which is connected to a magnetic tape end and has a hole at its own outer end adapted to be engaged with a corresponding hook of a drawing-out member of a recorder which too is formed of a relatively tough, elastic material (Japanese Patent Application Kokai No. 10-188520). When the cartridge incorporating the latter is not in use, the leader tape is held within the cartridge housing and the engaging hole of the leader tape is engaged with a hook inside the housing.
FIG. 10 is an exploded view of a conventional single-reel type cartridge 103 described in the specification of the above-mentioned Patent Application Kokai No. 10-188520. A housing of the cartridge including an upper casing 101 and a lower casing 102 is shown containing a single tape reel 107 which has an upper flange 104 and a lower flange 105 , the tape reel 107 being normally biased toward the lower door lock member 102 by a compression spring 108 . A leader tape 109 is spliced to the outer end of a length of magnetic tape 106 wound round a hub (not shown) of the upper flange 104 of the tape reel 107 . The tape reel 107 has a bearing (not shown) on a ring which is press fitted in an annular recess (not shown) formed in the center of the upper flange 104 . With a reel shaft (not shown) fitted in the bearing, the reel can revolve around the shaft. The upper flange 104 of the tape reel 107 has a serration 114 formed along its circumference. On the other hand, a pair of brake members 112 , 113 are provided on the inner surface 101 a of the upper casing 101 and are normally biased toward the serration 114 by torsion coil springs 110 , 111 , with cogs 115 , 116 , respectively, of the brake members 112 , 112 adapted to be in mesh with the serration to keep the tape reel from revolution when the cartridge is not in use. When the cartridge is on standby the magnetic tape 106 is wound up on the tape reel 107 , and an engaging hole formed at the end of the leader tape 109 is engaged with a hook 117 located close to a side wall of the cartridge housing 103 . An opening through which the magnetic tape 106 is drawn out from the cartridge housing 103 is normally closed by a lid 118 which is openable with respect to the cartridge housing.
For use, the cartridge is loaded into a recorder, and the brake members 112 , 113 are automatically set free and the tape reel 107 is lifted against the urging of the compression spring 108 to a position free to turn. At the same time, the lid 118 is opened by means provided for that purpose in the recorder.
The tape drawing-out member on the part of the recorder then enters the housing through the opening to be engaged with the hole of the leader tape 109 and draws out the magnetic tape together with the leader tape 109 in the manner described above, so that the tape is threaded in the route within the recorder. When the cartridge is not in use, the magnetic tape is housed within the cartridge and the leader tape is wound up too, with its engaging hole engaged with the hook 117 .
The leader tape 109 is made using a thick spring sheet of tough synthetic resin such as polyethylene terephthalate (PET). As FIGS. 11 ( a ) to 11 ( c ) indicate, a hole 128 is formed at the end of the tape so as to be engaged with a tab 121 (serving as a hook) formed at the end of a tape drawing-out member 122 of the recorder. The hole 128 has an angular cutout 123 to ensure positive engagement with the tab 121 , with a neck of the drawing-out member that supports the tab 121 fitted in the cutout. FIGS. 11 ( a ) to 11 ( c ) show a sequence of the stages in which the drawing-out member 122 is progressively engaged with the leader tape 109 as the drawing-out member enters the cartridge.
The tape drawing-out mechanism of the prior art causes the following problem. The tape drawing-out member 122 of the recorder, as shown in FIGS. 11 ( a ) to 11 ( c ), is in the form of a tape connected to a reel provided in the recorder, with the tape end having the tab 121 adapted to be engaged with the hole 128 of the leader tape in the tape cartridge. Since the end portions of the leader tape and the drawing-out member 122 of the recorder are both tape-shaped, they are susceptible to curling. When they both curl, it becomes sometimes impossible for the tape drawing-out member 122 of the recorder to engage the leader tape 109 of the cartridge loaded in the recorder.
On the other hand, direct coupling of the end of a magnetic tape to a tough leader member without the aid of a leader tape would stabilize the actions of drawing out and drawing in of the magnetic tape. Such a leader member, as illustrated in FIG. 1, comprises a center pin member 91 in the form of a pin on which a tape end is wound and secured in place by clamping, and a pair of engaging members 92 , 92 fixed at one ends to the upper and lower end of the pin member 91 . On the sides of the engaging members 92 , 92 facing each other, there are formed engaging recesses 92 - 1 , 92 - 2 in mirror symmetry (see FIG. 9) adapted to engage a pin or casing of a recorder. The center pin member 91 is made of metal and the engaging members 92 , 92 are made of plastic.
Users generally desire to enjoy recording and playback with both tape cartridges using a leader tape and a leader member on one and the same drive device. On the other hand, tape cartridge manufacturers commonly desire to minimize the investment in equipment to manufacture the two types of tape cassettes.
BRIEF SUMMARY OF THE INVENTION
The tape cartridge according to the present invention is one including a single tape reel around which a length of magnetic tape is wound and which is turnably held within a housing in such a manner that the beginning of the tape is drawn out through an opening formed in the housing by a tape drawing-out member of a recorder, said drawing-out member having an engaging means at the outer end, characterized in that the housing has both a cell in which a hook member to catch an engaging end of a leader tape, when the leader tape holding the beginning of the magnetic tape is used, is detachably fitted and a cell in which a leader member to hold the beginning of the magnetic tape, when the leader member is used, is contained.
In another aspect the tape cartridge according to the invention includes a single tape reel around which a length of magnetic tape is wound and which is turnably held within a housing in such a manner that the beginning of the tape is drawn out through an opening formed in the housing by a tape drawing-out member of a recorder, said drawing-out member having an engaging means at the outer end, said housing having a cell in which a hook member to catch an engaging end of a leader tape holding the beginning of the magnetic tape is detachably fitted, characterized in that the housing is made using a mold equipped with either a first replaceable mold part for forming a cell in which a leader member holding the beginning of the magnetic tape is contained or a second replaceable mold part that can replace the first mold part but does not form the cell to contain the leader member.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
FIG. 1 is an exploded view of a tape cartridge embodying the present invention;
FIG. 2 is a plan view of a combined-type upper casing according to the invention;
FIG. 3 is a plan view of a combined-type upper casing of the invention, with a hook member fitted in place;
FIG. 4 shows, in perspective, a combined-type upper casing of the invention with a hook member, 4 ( a ) as an exploded view and 4 ( b ) as an assembled view;
FIG. 5 is a plan view of a combined-type upper casing of the invention, accommodating a leader member;
FIG. 6 shows, in perspective, a combined-type upper casing of the invention with a leader member, 6 ( a ) as an exploded view and 6 ( b ) as an assembled view;
FIG. 7 is a perspective view of an upper casing made by a mold including a first replaceable mold part according to the invention;
FIG. 8 is a perspective view of an upper casing made by a mold including a second replaceable mold part according to the invention;
FIG. 9 shows, in perspective, relations between a tape drawing-out member of a recorder of combined type to which the present invention is applicable and the leader tape and the leader member of two different tape cassettes, 9 ( 1 ) showing the relation of the drawing-out member to the leader tape and 9 ( b ) the relation to the leader member;
FIG. 10 is an exploded view of a conventional tape cartridge; and
FIGS. 11 ( a ) to 11 ( c ) show ordinary relations between a conventional leader tape and drawing-out member of a recorder, FIGS. 11 ( a ) to 11 ( c ) showing a sequence of movements of the two members into mutual engagement.
DETAILED DESCRIPTION OF THE INVENTION
The present invention will be described in detail below in conjunction with some preferred embodiments thereof.
FIG. 1 is an exploded view of an embodiment of the invention.
Referring to FIG. 1, a tape cartridge according to the invention is shown upside down. It illustrates how the parts look in actual assembled operation. A complete cartridge is loaded, in the regular unreversed posture, in a recorder. The cartridge is similar in construction to the cartridge shown in FIG. 4 excepting the leader member and associated parts.
An upper casing 1 and a lower casing 2 are joined close to their comers using setscrews 23 to form a cartridge housing. A reel 3 on which a length of magnetic tape is wound is accommodated in the space inside the housing composed of the upper and lower casings.
The reel 3 consists of an upper flange 31 , a hub 33 formed in one piece with the upper flange, and a lower flange 32 . The underside of the hub 33 inward of the core on which the tape is wound is closed and is provided with an annular toothed part 34 . The upper side of the hub 33 constitutes an open recess which contains a rotational reel support 5 composed of a bearing 4 that smoothens the rotation of the reel, a ball 51 in contact with the center of the bearing 4 , and a support member 52 recessed at top to receive the ball. The upper end of the support member 52 is received by a blind hole in the upper casing 1 , and a coiled compression spring 6 loosely fitted around the support member normally urges the bearing 4 and the rotational reel support 5 toward the reel.
An irregular surface 35 is formed along the circumference of the upper flange 31 , and there are provided two brake mechanisms each composed of one of a pair of pins 13 , 14 held upright on two diagonal comers inside the housing, a coiled torsion spring 72 , and a brake member 71 with a bore, the spring and brake member being fitted on the pin. When the cartridge is not in use, the two brake mechanisms co-act to engage the brake members 71 with the irregular surface 35 on the circumference of the upper flange 31 so as to keep the reel from unwanted rotation.
The outer end of the tape is fixed to a leader member 9 . The leader member 9 is made up of a center pin 91 , a pair of engaging members 92 fixed at one end to the upper and lower ends of the pin member, and a clamp 93 for clamping the tape end to the pin 91 . The tape end is wound round the center pin 91 and is secured in place with the clamp 93 fitted onto it. The leader member 9 is housed in a recess 11 formed near the inner surface of an opening formed on one side of the housing.
On the outer side of the leader member is fitted a turnable door member 81 . The door member 81 is pivotally supported by a pin 15 of the upper casing 1 and is normally biased to a closing position by a torsion coil spring 84 fitted around the pin 15 . When the cartridge is not in use, it is locked by a door lock member 82 under downward urging by a compression spring 83 . A record defeat member 12 is held in a part of one side of the housing, slidably along that side.
For a better understanding of the present invention, the description of the cartridge housing according to the invention will be preceded by an explanation of a leader tape type and a leader member type with reference to FIG. 9 . In the illustrated example a tape drawing-out member 122 of a recorder, as shown in FIG. 9 ( a ), has a tab 121 adapted to engage a hole 128 of a leader tape 109 . It also has a pin 125 , as in FIG. 9 ( b ), which has flanges 124 at both ends adapted to fit in engaging recesses 92 - 1 , 92 - 2 of engaging members 92 of a leader member 9 . The recorder sometimes may use only one of the two leader types.
FIG. 9 ( a ) shows the relation between a tape cartridge of the leader tape type and a drawing-out member. The leader tape 109 has a hole 128 formed at its outer end for engagement purposes, and while it is withdrawn in the tape cartridge, the hole 128 receives a hook member 17 (FIGS. 3 and 4) that comes in the passage for the leader tape 109 (as well as the magnetic tape ). When the drawing-out member 122 of the recorder gains entrance into the cartridge to draw out the magnetic tape, the tab 121 formed at the end of the drawing-out member 122 as shown engages the hole 128 of the leader tape 109 to draw out the leader tape 109 .
FIG. 9 ( b ) shows the relation between a tape cartridge of the leader member type and a drawing-out member. Here no leader tape is used, and the outer end of the magnetic tape is wound round the center pin member 91 of the leader member 9 and is clamped ( 93 in FIG. 1) securely. While the tape is withdrawn in the tape cartridge, the leader member 9 is housed in the recess 11 provided for that purpose as indicated in FIGS. 5 and 6. When the drawing-out member 122 enters the cartridge to draw out the magnetic tape, the flanges 124 of the pin 125 provided at the end of the drawing-out member as shown engage the recesses 92 - 1 , 92 - 2 of engaging members 92 of the leader member type, whereby the leader member 9 is pulled out.
Now, in connection with FIGS. 2 to 6 , a housing of a tape cartridge embodying the invention will be explained.
Referring to FIG. 2, an upper casing 1 is shown with a guide wall 19 formed close to one side wall to draw out a magnetic tape. A hook cell 16 to hold a hook member 17 is formed opposite to the guide wall. A leader member-containing cell 11 into which one of the engaging members 92 of the leader member 9 fits is formed contiguous to an end of the guide wall. The hook member 17 and the leader member-containing cell 11 are alternatively used, depending on the structure of the member of the recorder that draws out the tape from the cartridge. The combined system thus far described in conjunction with FIG. 9 is applicable to tape cartridges using either the leader tape type or leader member type. The tape cartridge itself has an indication of which type it is designed for.
The hook cell 16 comprises a continuous surrounding wall forming a generally triangular space in which the hook member 17 fits snugly. When the housing is to be assembled as a leader tape type, as illustrated in FIGS. 3 and 4, the hook member 17 is fitted securely in the cell. A hook 17 - 1 at the end of the hook member 17 projects toward the guide wall 19 , exposing itself partly in the path of the leader tape.
On the other hand, the leader member-containing cell 11 is formed contiguous to the guide wall 19 . It is formed away from the path in which the tape travels, lest the cell interfere with the running of the magnetic tape and the movement of the tape drawing-out member of a recorder. The adjoining end of the guide wall 19 extends over a part of the leader member-containing cell 11 to constitute a part of the wall of the cell. When the housing is to be built as one of the leader member type, as shown in FIGS. 5 and 6, one of the engaging members 92 of the leader member 9 that clamps an end of the magnetic tape on its center pin member 91 is fitted in the cell 11 .
According to the present invention, as described above, both the cells for the hook member and the leader member are arranged along the path in which the tape travels. Thus one and the same housing serves the combined purpose of the leader member type and the leader tape type. This adds to the economy of cartridge manufacture, since a single mold can be utilized in making cartridges of the two types.
Next, referring to FIGS. 7 and 8, another embodiment of the invention will be described. In these figures the identical parts, excepting the portions surrounded by broken lines 200 , 201 , are the parts of two upper casings molded of plastic by mold parts common to both.
In FIG. 7, the portion surrounded by the broken line 201 is a portion formed using a first replaceable mold part. This means that the upper casing 1 shown was made by a mold combining a common mold part and the first replaceable mold part. The first replaceable mold part has a mold cavity contour for forming a leader member-containing cell 11 . In this manner a tape cartridge that can incorporate both the leader tape type and leader member type is provided.
Referring to FIG. 8, the portion surrounded by the broken line 200 is a portion formed using a second replaceable mold part. In other words the upper casing 1 shown was made by a mold combining a common mold part and the second replaceable mold part. The second replaceable mold part does not have a mold cavity contour for forming a leader member-containing cell; it simply forms a side wall as an uninterrupted extension of the guide wall. In this manner the upper casing permits the manufacture of a tape cartridge of the leader tape type.
Although the construction of the mold is not illustrated, the cavity surface of the mold has a shape complimentary to that of the molded product, and therefore the mold construction should be obvious to those skilled in the art from the foregoing description as well as from the illustrations.
As has been described, the present invention renders it possible to manufacture tape cassettes at lower cost than heretofore because it advantageously permits the production of cartridge housings with alternate tape drawing-out types, (1) housings combining the leader tape type and the leader member type and (2) housings that selectively use the leader tape type alone or combine the leader tape and leader member types. | A tape cartridge includes a single tape reel around which a length of magnetic tape is wound and which is turnably held within a housing. The beginning of the tape is drawn out through an opening formed in the housing by a tape drawing-out member of a recorder. The drawing-out member has an engaging member at the outer end. The housing has a cell in which a hook member to catch an engaging end of a leader tape, when the leader tape holding the beginning of the magnetic tape is used, is detachably fitted and a cell in which a leader member to hold the beginning of the magnetic tape, when the leader member is used, is contained. The housing is made using a mold which forms a cell having a leader member holding the beginning of the magnetic tape or which forms the cell without the leader member. | 6 |
This application is a CIP of PCT/IB2005/054213 filed on Dec. 13, 2005.
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention concerns a security system, and in particular a security system for securing a set of keys to, in order to enable the ease of location thereof in the case of an emergency, such as a house fire or the like, in addition to providing a straightforward security system for preventing the theft of house or vehicle keys or the like.
[0003] 2. Related Background Art
[0004] With the introduction of more anti-theft devices in vehicles, it is becoming more common for burglaries to be committed simply to obtain a set of keys such as vehicle keys. In many cases the owner of the vehicle is unaware that the keys have been taken until they see that the car is no longer parked outside the premises. It is therefore becoming more and more common, particularly at night when occupants are asleep, not to leave keys within easy reach of possible burglars.
[0005] However, placing keys out of reach can often have fatal consequences. Many house fires lead to injury or death when the occupants cannot exit the house because the doors thereto are locked. In the panic that ensues during a fire, the people affected may not be able to locate the keys because of the shock experienced, or due to heavy smoke which leads to additional confusion, especially when the keys are not immediately to hand. House fires normally incapacitate some but not all people within the household. Children often lose their lives or are seriously injured in searching for parents to unlock doors and offer assistance in exiting the premises, while the parents themselves are often unaware as to the exact location of the keys, and thus valuable time is wasted.
[0006] It is therefore an aim of the present invention to provide a security system adapted to secure a set of keys thereto, in order to prevent the unauthorised removal thereof. In addition the invention seeks to provide a fixed location at which the keys may be found and also a warning system if for example a fire breaks out in a home.
SUMMARY OF THE INVENTION
[0007] According to the present invention, as seen from a first aspect, there is provided a security system comprising a housing having an aperture for receiving a security tag which is to be attached to one or more keys, the aperture being associated with a locking mechanism operable to secure the security tag in or release the tag from the aperture, a sensor to monitor the presence of the security tag in the aperture, and alarm means for generating a warning signal if the security tag is removed from the housing without operation of the locking means.
[0008] In use, a security tag can be fitted to a bunch of keys and the keys can be securely stored by inserting the tag into the aperture of the system.
[0009] The system will not release the tag until the locking mechanism has been de-activated, thereby preventing the theft of the keys. A warning signal will be generated if the keys are removed without de-activating the system.
[0010] The locking mechanism may be arranged to releasably engage the tag, so that the keys can be removed from the system in an emergency, thereby triggering the alarm to alert other persons of the emergency. It is envisaged that the system may be able to optionally releasably engage the tag, so that the removal of car keys can be prevented, whilst the removal of house keys is permitted.
[0011] Preferably, means are provided for monitoring one or more environmental conditions in proximity to the housing and for actuating the alarm means if predetermined parameters for the monitored environmental conditions are not met.
[0012] In a preferred arrangement, said monitoring means is arranged to monitor for one or more environmental conditions selected from one or more of noise, smoke, heat or carbon-dioxide levels.
[0013] It is preferred that the locking mechanism is operated by a keypad which receives an input to lock or disengage the security tag in or from the aperture.
[0014] In a preferred arrangement, the security tag includes a microchip that can be read by a detector in the housing in order to verify the authenticity of the tag.
[0015] It is envisaged that the housing includes a memory, whereby different inputs can be allocated to different key holders.
[0016] It is further envisaged that the memory can be programmed to store varying data relating to the security level required for each key associated with a security tag. For example, if a security tag is attached to keys such as a front door key or a car key where only certain persons are meant to use the key, a memory for the security system can be programmed so that a more complicated or different code input would have to be input via the keypad to release the key from the housing than for say an internal door.
[0017] It is envisaged that the alarm means can generate an audible warning signal.
[0018] Further, the alarm means is operable to generate a visible warning signal. However, it is envisaged that if required, both and audible and a visible warning signal can be generated.
[0019] In a preferred arrangement, the housing also includes one or more lights which are operable to illuminate the security device when the warning signal is generated. This inclusion of lights has the benefit that the housing and keys can be more easily found in a smoke filled environment which improves the chances of householders being able to escape in an emergency situation. The lights can also be used to illuminate an exit for people to escape from a smoke filled room.
[0020] Preferably the lights are arranged to illuminate a keypad of the system.
[0021] Preferably, the housing also includes an override that is operable to turn off the alarm means. The override is in the form of an on/off switch for a power supply to the security device. This feature is useful in case there is inadvertent operation of the device, for example if a child rather than an intruder tries to remove the key without permission.
[0022] In a preferred arrangement, the security system includes switch means so that the system can be switched between sensing the presence of a security tag and environmental conditions or only monitoring the presence of a security tag or environmental conditions. By having the facility to switch between different levels of functions, this provides for maximum adaptability of the device. It may be that at certain times, for example during the day, the only need is to monitor for unauthorised removal of a key, while at night there is also the need to detect whether a fire has started so that house occupants can be alerted to escape as quickly as possible.
[0023] It is envisaged that the invention is also directed to a kit of parts comprising a housing as previously described, together with one or more security tags as herein mentioned.
[0024] In a preferred arrangement, the security tag is arranged for attachment to the key by a wire cable, preferably a twisted wire cable passing through an aperture in the key.
[0025] Preferably, the wire cable is secured to the fob by lockable securing members, such as nuts, which can be released to change keys for the tag or put more keys on the wire cable for a security tag.
[0026] Preferably, the securing means is in proximity to the security tag such that when the tag is placed in the aperture of the housing, the securing means are not accessible so that the securing means cannot be released to release the key from the security tag.
[0027] In an alternative arrangement, the security tag is secured to the body of the key, with the key being inserted in the aperture in the housing and locked in position.
[0028] It is envisaged that the security tag is provided as a plastic key which is attachable by a cable to a domestic key. However, the security tag can be a device which is clipped to the key itself.
[0029] Further, the invention is also directed to security tags as mentioned, which can be supplied separately for householders to attach to existing keys so that these existing keys can be secured by the security system.
[0030] Also, according to the present invention, as seen from a second aspect, there is provided a security system comprising a housing having an aperture for receiving a key, the aperture being associated with a locking mechanism operable to secure the key in or release the key from the aperture, a sensor to monitor the presence of the key in the aperture, and a signal generator that is operable to actuate a warning signal if the security key is removed from the housing without operation of the locking means.
BRIEF DESCRIPTION OF THE DRAWINGS
[0031] The present invention will now be described by way of examples only with reference to the accompanying drawings, in which:
[0032] FIG. 1 illustrates a front elevation of an embodiment of security system according to the present invention and a key and fob for releasable engagement with a housing of the system; and
[0033] FIG. 2 illustrates a front elevation of an embodiment of security system according to the present invention with a key inserted in a housing of the system.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0034] Referring now to FIG. 1 of the accompanying drawings, there is illustrated an embodiment of security system, generally indicated as 10 , which serves to both locate and secure a key 28 or set of keys such as house or car keys, at a given location, for both safety and security reasons.
[0035] The security system 10 consists of a housing 12 which may be formed from any suitable material, for example plastic, preferably a thermosetting plastic or other heat resistant material. The choice of a heat resistant material for the housing 12 is important as the security system 10 , as will be described hereinafter, is intended to serve as a beacon or guide during emergencies such as house fires, where significant heat may be experienced, under which conditions the security system 10 must continue to operate. The housing 12 defines a chamber in the form of a slot 14 on the underside of the housing, which is shaped and dimensioned to receive a security tag 26 which may be in the form of a fob or a key.
[0036] In use, security tag 26 is securely connected to the key 28 or set of keys (not shown), by way of a shackle which is secured by nut 31 on either side of a mounting plate 32 which is attached to an end of the security tag 26 closest to the key. The key 28 may then be secured to the security system 10 via the security tag 26 . It should however be appreciated that the slot 14 could be adapted to directly receive the key 28 , although the use of the security tag 26 lends greater versatility to the security system 10 , allowing same to be used with keys (not shown) of varying shape and size.
[0037] The security system 10 is provided with a keypad 16 which, once the security tag 26 has been inserted into the slot 14 , may be used to lock the security tag 26 within the slot 14 . The keypad 16 may be configured to accept a single or multi-digit code which, when entered, locks the security tag within the slot 14 , by any conventional means. The slot 14 is configured to position the tag 26 in such a position that the nuts 31 securing the shackle 30 are inaccessible, such that when the tag 26 is locked in-situ, it is impossible to undo the nuts 31 to release the key 28 . The keypad 16 is preferably backlit, or otherwise rendered highly visible in darkness or low visibility (for example in the presence of smoke), in order to ensure that the keypad 16 may be actuated, without delay, during an emergency. The security system is also configured to effect release of the security tag 26 , and thus the key 28 , from the slot 14 upon a code being entered on the keypad 16 . Different lock and release codes may be utilised, however it will be appreciated that using the same code for both operations simplifies the use of the security device 10 , which is an important consideration given the intended function thereof.
[0038] Once the security tag 26 has been inserted into the slot 14 , and the keypad 16 utilised to lock same, the security system 10 is alarmed, and will emit an alarm signal if any attempt is made to remove the security tag 26 without first entering the correct release code. In order to generate an alarm signal, the security system 10 is provided with a plurality of lights 18 disposed about the housing 12 to provide a visible warning. In addition a speaker 20 can provide an audible alarm and the speaker is actuated by internal control circuitry (not shown) preferably of conventional electronic form. The control circuitry may be configured and adapted to trigger either a visual or audible alarm signal, or both, in response to a large number of external events.
[0039] One such way in which the alarm may be triggered is when an incorrect code is entered on the keypad 16 , although the device 10 may be configured to permit one incorrect entry of the release code, before triggering the alarm.
[0040] The security system 10 is also preferably provided with a sound detector 22 of any suitable form, which is operable to trigger the alarm in response to smoke or a certain frequency/pitch/volume, in particular to the audio alarm emitted by household smoke alarms (not shown). Thus, in the event of a fire, in addition to the sound of a smoke alarm, the security system 10 itself will issue a further audible/visual alarm. The visual alarm effected by the plurality of lights 18 is of particular benefit, in the event of a fire, as the lights 18 will serve to guide a person directly to the system 10 , and so the key 26 located and secured therein, even in the presence of smoke.
[0041] As an alternative, the security system 10 could be provided with an on board smoke/heat/carbon monoxide detector (not shown), which would be configured to trigger the alarm of the security system 10 directly. In addition, the security system 10 is preferably provided with internal vibration detectors (not shown), for example a conventional piezo-electric accelerometer based detector or the like. These detectors (not shown) are operable to detect any tampering with the security system 10 , and trigger the alarm in response thereto.
[0042] Thus, in use, the security system 10 is secured at a desired location, via a pair of fixing screws 24 , or indeed any other suitable means. The security system 10 is preferably secured close to an exit, such as a front door (not shown), in order to act as a guide to direct any occupants to both the exit and the keys necessary to unlock same. Once the security system 10 is fixed in position, and an occupant is present on the premises, the key 28 to the premises, or indeed the occupants vehicle, is secured to the security system 10 as hereinbefore described. The security system 10 will then serve two purposes. If as detailed above, the premises are broken into to obtain the keys to the occupant's vehicle, the keys cannot be removed from the security system 10 without triggering the alarm, thereby alerting the occupant to the attempted robbery. In addition the security system 10 serves as a fixed location at which the occupant's keys are located, avoiding the possibility of misplacing the keys.
[0043] The second function of the security system 10 is to serve as an emergency indicator, preferably pinpointing the location of an exit (not shown), in addition to the keys for same. Thus, in the event of a fire, the lights 18 will be activated as hereinbefore described, guiding the occupants to the security system 10 , and therefore the key 28 . The occupant then disarms the security system 10 by keying in the release code on the keypad 16 , and removes the key 28 to unlock the door. Any further occupants will then be guided to the opened door by the lights 18 , guiding the further occupants to safety.
[0044] The security system 10 may be configured to automatically disarm in the event of a fire, preventing the need to key in the release code, thereby reducing the time taken for the occupant to open a given door to exit the premises.
[0045] Alternatively, the keypad 16 may be entirely omitted, and possibly replaced with a simple on/off switch (not shown), such that the security system 10 still serves to guide an occupant to the key 28 , which can then be quickly and easily removed to enable the door to the premises to be unlocked.
[0046] Referring now to FIG. 2 of the accompanying drawings, there is illustrated an alternative embodiment of security system which is similar to the system of FIG. 1 and like parts are given reference numerals. In this embodiment the key 28 is received directly in the slot 14 .
[0047] While the preferred embodiments of the invention have been shown and described, it will be understood by those skilled in the art that changes of modifications may be made thereto without departing from the true spirit and scope of the invention. | A security system for securing a set of keys comprises a housing having an external aperture for receiving a security tag which is attached to the keys, the aperture being associated with a locking mechanism which is operable by a keypad to secure the security tag in or release the tag from the aperture. A sensor monitors the presence of the security tag in the aperture, and an alarm is activated if the security tag is removed from the housing without releasing the locking mechanism. The security system eases the location of the keys in an emergency and also provides a straightforward security system for preventing the theft of house or vehicle keys or the like. | 4 |
BACKGROUND OF THE INVENTION
The invention concerns a process for manufacturing and/or treating an endless tubular felt or similar tubular structure. A material, for instance, a fiber web, a coating, longitudinal threads or the like, are deposited continuously across the width. An at least partially prepared tubular felt revolves circumferentially with the deposition being in that direction. The tubular felt may be treated across a width which has been singed or needled and with the width being less than the width of the tubular felt. The deposition or the treatment takes place, respectively, by a relative motion of, or toward, the tubular felt in a helical manner transversely to its direction of advance and possibly with partial overlap. The invention further relates to an apparatus to implement this process and comprises at least two mutually spaced conveyor rollers for the already-prepared part of the tubular felt. A feed system for depositing the material on the already-prepared part of the tubular felt and/or with a treatment system for said part is disclosed. A displacement device for the relative motion between the tubular felt and the feed system or the treatment system is provided in the axial direction of the conveyor rollers.
Such a process and pertinent equipment is disclosed in the German Pat. No. 16 60 765. To that end, the equipment includes two mutually adjustable conveyor rollers on which the already-prepared part of the tubular felt moves. A fiber-web is continuously supplied in the direction of rotation of the tubular felt in such a manner that this length of fiber web partly overlaps the already-prepared tubular felt by one edge. After the fiber web is deposited, it is needled to the tubular felt. Grooves are fashioned into the conveyor rollers parallel to their longitudinal axes and are adapted to receive moving conveyor chains which support needles for penetrating the felt. These conveyor chains slowly displace the tubular felt transversely to its direction of advance, whereby the tubular felt is gradually built-up over its entire width. It has been found in practice that the transverse motion of the tubular felt does not coincide with the motion of the conveyor chains. This was noted when the computed tube width was not obtained after a computed number of tube revolutions. The reasons for this discrepancy have not been reliably ascertained. As a consequence, the specific weight per area and hence the thickness of the particular tubular felt varies greatly and, consequently, the dehydration properties and also the service life of the tubular felt are degraded when used in a paper-making machine.
The equipment disclosed in the German Auslegeschrift No. 23 24 985 operates in the kinematic reverse order. In this equipment, the tubular felt is not displaced transversely but rather the feed system for the fiber web is. However, the tubular felt is similarly formed by the length of fiber web being opposed helically with partial overlap.
In this instance, too, the lengths of fiber web must be so deposited that there will be no changes in specific weight per area or thickness. These changes may be caused, for instance, by an uncontrolled drift of the tube on the conveyor rollers or by fluctuations in the transverse motion of the feed system.
Similar problems are incurred if in lieu of a length of fiber web, coatings or chemicals are deposited in helical manner. Again, the spacings of the "pitches" on the tubular felt must always be of a predetermined value in order to have uniform deposition.
Similar considerations apply to treatments and procedures such as singeing, needling, brushing or the like. One may move a corresponding device of lesser width across the width of the circumferentially rotating tubular felt or, vice-versa, the tubular felt can be moved transversely underneath the stationary device. Similar kinematic relations apply when treating tubular felts or corresponding tubular structures in roll calenders.
Lastly, threads forming longitudinal dehydration channels which are mutually spaced apart can also be deposited to form a tubular felt by placing one or more threads next to each other in the gaps of a reed on the surface of the tubular felt. By transversely moving either the tubular felt or the feed system for the threads, these threads may be arrayed helically on the tubular felt. Uniformly spaced filaments are also essential in this instance.
OBJECTS AND SUMMARY OF THE INVENTION
It is the object of the invention to so improve the initially cited process that there results a uniform material deposition or a uniform treatment of the tubular felt.
Another object is to provide an apparatus to carry out this process.
The first stated object is solved by the invention in that at least one marking line, in contrast with the tubular felt, is continuously deposited on said felt in its circumferential direction of advance. The position of said marking line, or its spacing from a neighboring one toward the rear, as shown from the direction of advance, is sensed in a contact-free manner as the actual value. The relative motion is always set so that the sensed actual value deviates as little as possible from a specific reference value. In a manner of speaking, the marking line acts as an indicator of the actual relative motion between the tubular felt and the deposition or the treatment. The transverse displacement of the marking line from the place where it was deposited is sensed in a contact-free manner and this actual value is then compared to a reference value. The actual value can be balanced against the reference value by a fine-control for the transverse motion drive and thereby a most uniform transverse motion is achieved. This uniform transverse motion assures, for instance, in the case of the deposition of a fiber web, that the continuous build-up of the tubular felt takes place in optimal manner with the thickness being substantially the same across the whole width.
The sensing of the marking line can be performed at various sites. It was found advantageous to sense the position of the making line before the tubular felt with the marking line has carried out a full revolution. In this range, the transverse motion is especially clear and hence easily sensed, although suffering from the drawback that this sensing occurs shortly before a full revolution is completed.
Alternatively to sensing the position of the marking thread upon completing a specified path, one can also sense the spacing between the revolution(s) of a marking line. In that event, the marking line forms a helical line on the already-prepared tubular felt, the spacing between the adjacent parts of the line being a measure of the particular transverse motion.
Such a measurement of the spacing also can be carried out when a first marking line and a second marking line behind said first, as seen in the direction of advance and at a spacing from it, are deposited, with the sensing of the spacing between the two marking lines then being carried out. This procedure offers the advantage of not having to wait for a full revolution of the marking line before sensing the spacing.
Just because the marking line is continuously deposited does not mean that it must be uninterrupted. It also suffices if the marking line consists of dashes or dots. An ink or color which can be rinsed out, for example, is suitable material for the marking line. It was found especially appropriate to use marking threads having a strong color contrast compared to the color of the tubular felt as the marking line. Appropriate marking threads are yarns which are as smooth as possible, in particular when, in an especially advantageous manner, the marking filament is deposited before a length of fiber web is fastened to the already-prepared part of the tubular felt. In that case the marking thread is so needled to the tubular felt that it will not change its position thereafter. Despite this needling operation, the thread can be removed without problems after the sensing and without damaging the tubular felt.
Where the marking line contrasts optically with the tubular felt, optical procedures are especially applicable as the sensing methods.
An apparatus to implement this process is disclosed in the invention and includes at least one deposition system continuously depositing the marking line on the tubular felt along its circumferential direction. A sensing system operating in contact-free manner detects the position of the marking line or its spacing from a neighboring marking line which, as seen in the direction of advance, is located behind the deposition system(s). The deposition system(s) and the sensing system are fixed in position and with respect to each other when the tubular felt is moved transversely and are coupled to the displacement device when the feed system or the treatment system is moved transversely. The sensing system is connected to an electronic analyzer which ascertains the difference between the actual value of the position or the spacing between the marking line(s) on one hand and on the other the reference value provided for that purpose. The analyzing unit is connected to a regulator adapted for ascertaining the setting value and for adjusting the drive of the displacement device for minimizing the difference. The apparatus of the invention is therefore provided with a regulator for implementing the process of the invention. The actual value of the transverse displacement fed to the regulator is obtained from the position of the marking line or from the spacing between two neighboring marking lines. The regulator so acts on the displacement device that the actual transverse displacement of the tubular felt corresponds as uniformly as possible to a pre-determined reference value.
In the embodiment of the invention, the deposition system(s) is (are) mounted in front of a fastening device. This is especially advantageous if the marking line is in the form of a marking thread because the latter is then fixed by the fastening device onto the tubular felt.
When the spacing between two marking lines is used as the actual value in controlling the transverse motion, a second deposition system can be mounted behind the first as seen in the direction of advance. The magnitude of the spacing between the marking lines deposited by the two deposition systems in this case corresponds to the actual transverse motion of the tubular felt.
Alternatively, the sensor means can be mounted between adjacent parts of the marking line after more than one revolution. The sensor can be designed to detect the spacing between the two adjacent parts of this marking line. In that case, however, while the spacing is also sensed as the actual value, only one marking line need be deposited.
A further feature of the invention provides that the sensor is mounted in the vicinity of the marking line shortly before the completion of one revolution and that the sensor is designed to detect the position of the marking line. In practice, this sensor was found useful in spite of the relatively large distance between the depositing and sensing of the marking line because the change in position is especially noticeable in this vicinity when there is a change in the transverse motion.
The invention further provides that the marking line(s) optically contrasts with the tubular felt and that the sensor is an electronic-optical type. This provides the simplest method for depositing a marking line and sensing it. This sensing may include a light detector of the known type of scanners or light-interruption detectors.
However, another alternative found to be problem-free was to provide the sensor with an imaging device. This can be implemented, for instance, with a semiconductor imaging sensor of the CCD techniques. These detectors are still relatively expensive and accordingly, at the present, the imaging device more likely will be a video camera, especially one with a vidicon tube.
The video camera is arranged such that the marking line(s) run parallel to the camera's scanning lines in order to obtain a video signal of constant signal amplitude between two line sweep pulses. Additionally and preferably, the video camera and the marking line(s) are adjusted with respect to each other so so that the marking line(s) require(s) at least six scanning lines. The purpose is to obtain a clear video signal regardless of any spurious pulses.
Appropriately, the analyzer includes a detector circuit to detect the marking line(s) and a counter circuit to count the scanning lines from the beginning of the image to the video signal of the marking line(s) and/or between two such video signals. The count is the actual value to be used by the regulator. The detector circuit may be designed to include a shift register which is synchronized by the line sweep pulses of the video camera and which is reset each time by the sweep pulses of the video camera for the purpose of transmitting line sweep pulses. The video signal controls an input port so that only the line sweep pulses enter the shift register in the presence of the video signal from the marking line(s). The shift register should be followed by an AND circuit emitting a signal only when three consecutive line sweep pulses are present. In this manner, signal transmission is extensively assured against any spurious pulses.
The counter circuit, in a further feature of the invention, consists of a line sweep pulse counter, a line sweep pulse memory connected to said counter and also a counter fed by a multivibrator. This latter counter is controlled by every second sweep pulse in such a manner that the line sweep pulse memory receives a transfer pulse to accept the count in the line sweep pulse counter and then the line sweep pulse counter receives a reset-pulse before the next line sweep pulse arrives. By means of this circuit, the line sweep pulses of two half images are recorded in the line sweep pulse counter and are fed into a memory. The line sweep pulse counter is reset into its initial state and it can again record the line sweep pulses of two half images.
A gate may be provided in front of the input to the line sweep pulse counter. The gate is controlled by the detector circuit through the use of a counting flip-flop and it will be blocking in the presence of a signal from the detector circuit and transmitting in the presence of an image sweep pulse. In this manner, only the line sweep pulses which were obtained from the beginning of the half image to the complete detection of the marking line are fed into the line sweep pulse counter.
In order that the spacing between the two marking lines will be detectable, a data flip-flop is provided in parallel with the counter flip-flop and can be switched to the gate in lieu of said counter flip-flop. The data flip-flop is controlled by the counter flip-flop and the detector circuit and in the presence of a first signal from the detector circuit the gate will be made transmitting and in the presence of a second signal it will again be blocking.
The regulator appropriately is a PI control. Such a regulator was found adequate and therefore a PID control is not necessary.
It was found to be especially advantageous to control the regulator by using a microprocessor because in that case a very flexible control is possible by the use of corresponding software.
Appropriately, the reference value input and the setting value output are implemented by an optical coupler so that the microprocessor is electrically isolated from the input and output.
The invention further provides that the deposit system(s) comprise(s) a spool holding the marking thread. A storage supply preferably is mounted between the spool and the tubular felt so that the marking thread can be taken off the spool in a problem-free manner. A guide plate is provided with a guide groove and, preferably, moves the marking thread onto the tubular felt.
Moreover, a take-off means preferably is provided for the marking thread and consists of a motor-driven spool. Appropriately, switches are provided to control the spool drive as a function of the take-off angle of the marking thread so that precise synchronization with the rotation of the tubular felt will not be necessary.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic sideview,
FIG. 2 is a top view of an apparatus for manufacturing a tubular felt,
FIG. 3 schematically shows the build-up of the tubular felt when the transverse motion is correct,
FIG. 4 schematically shows the build-up of the tubular felt when the transverse motion is excessive,
FIG. 5 schematically shows the build-up of the tubular felt when the transverse motion is insufficient,
FIG. 6 schematically shows in sideview the feed of a marking thread,
FIG. 7 schematically shows the take-off means for the marking thread,
FIG. 8 is a block circuit diagram of a detector circuit for a video camera signal analyzer,
FIG. 9 is a block circuit diagram of the analyzer with the detector circuit of FIG. 8, and,
FIG. 10 is a block circuit diagram of a regulator controlled by the analyzer of FIG. 9.
DESCRIPTION OF THE INVENTION
The apparatus, as best shown in FIGS. 1 and 2, essentially consists of two mutually spaced and axially parallel conveyor rollers 1,2 around which an already partly built-up tubular felt is guided. The conveyor rollers are provided with grooves 4,5, parallel to their axes and distributed across their circumferences, inside which grooves are guided conveyor chains 6,7. These conveyor chains hold needle segments 8,9 for penetrating the tubular felt 3.
The conveyor rollers 1,2 rotate the tubular felt 3 in the direction of the arrow A. Simultaneously, the tubular felt 3 is displaced transversely by the conveyor chains 6,7 and needle segments 8,9 in the direction of the arrows B,C.
A length of fiber web 10 is deposited on the upper edge of the tubular felt 3 of FIG. 2. This fiber web is supplied from a card and moves in the direction of the arrow D. The fiber web 10, in this procedure, overlaps by two-thirds of its width the already built-up tubular felt 3. It is fastened by a needling machine 11 located behind the first conveyor roller 1 and is fixed to the tubular felt 3. FIG. 1 shows dual needling machine 11 which fix the tubular felt 3 both at the upper and the lower sides of the felt 3. So far, this apparatus coincides generally with the equipment disclosed in the German Pat. No. 16 60 765.
As indicated merely in schematic manner in FIGS. 1 and 2, but in further detail in FIG. 6, a marking thread 13 is taken from cone 12 and is deposited by means of devices further described below at a given site on the tubular felt 3. This occurs in front of the needling machine 11 so that the marking thread 13 is needled to the tubular felt 3. The marking thread 13 then moves together with the tubular felt 3 along the helical line shown in FIG. 2. Near the conveyor roller 1, this thread is removed by a winding means 14 from the surface of the tubular felt 3 and is wound on said means. Before that, however, the position it assumed on account of the transverse motion was recorded by a video camera 15 having a vidicon tube.
The marking thread 13 and the location of the video camera 15 are mutually arranged so that the marking thread 13 will be parallel to the scanning lines of the video camera 15 in the recorded video image and that the video camera 15 records the marking thread 13 by at least 6 scan lines, i.e. at least 3 scan lines per half image. Illuminating means may be mounted beside the video camera 15 so that the marking thread 13 contrasts as much as possible with the surface of the tubular felt 3. Furthermore, maximum color contrast between the said thread and the color of the tubular felt 3 is preferred. This can be achieved as a rule by using a deep black thread while the tubular felt 3 typically is very light.
The most desirable marking thread 13 is a thread which is as smooth as possible but which has a fiber structure to permit it to be needled and fixed into the surface of the tubular felt 3. Obviously, the marking line 13 can also be replaced by one deposited using crayons or the like, also fluorescent inks. Additionally, metal threads may be deposited, provided the sensor means are appropriate.
FIGS. 3 through 5 show the stepwise build up caused by superimposed portions of the tubular felt. First, a length of fiber web a, here shown in cross-section, is provided. Another length of fiber web b is deposited on the first one in such a manner that two thirds of its width will rest on the length of fiber web a and one third of the width projects at the left edge. Another length of fiber web c is next deposited on the length of fiber web b so as to overlap it by two thirds and then a length d on the length c. The subsequent lengths of fiber web in turn are deposited in the same manner on the particular preceding lengths of fiber web as is the length d. It can be seen that the tubular felt built-up in this manner results in three plies of fiber webs which are mutually needled. In the example of FIG. 3, the transverse displacement is optimal and therefore the specific weight per area is uniform.
In principle, FIG. 4 shows the same build up of a tubular felt except that in this case the transverse displacement in the direction of the arrow E is excessive. In this case, the overlap of the fiber web b' with the fiber web a' is less than two thirds its width. This continues, of course, with the fiber web c' and the fiber web d'. A gap occurs between the particular upper parts of the fiber webs c' and d'. Theoretically, the thickness is only double that of a single length of fiber web in lieu of the desired triple amount. Such a discontinuity in thickness degrades the properties of the tubular felt but frequently took place with the equipment of the German Pat. No. 16 60 765.
Similar conditions apply when, as shown in FIG. 5, the transverse motion in the direction of the arrow E is too slow. It can be seen that then the overlap between the length of fiber web b" and the length of fiber web a" is more than two thirds of the width of the length of fiber web b". This continues with the fiber webs c" and d" and upon depositing the fiber web d", the theoretical thickness of the tubular felt in a segment is four-fold that of one fiber-web ply. This becomes even clearer in the latter case when depositing a further length of fiber web e". A tubular felt now has been made with a theoretical thickness of four fiber web plies, the periodically occurring gaps causing large differences in thickness and hence in specific weights per unit area. To prevent the conditions shown in FIGS. 4 and 5, a regulator is provided which is described further below.
FIG. 6 shows in further detail the deposition system for the marking thread 13. FIG. 6 is a side view and the arrow A denotes the direction of motion of the tubular felt 3. Initially, the marking thread 13 is stored on a cone 12 which is provided with a takeoff net 16. The marking thread is taken off the cone 12 at its head and passes through the guide eyes 17, 18, 19 to arrive at a supply spool 20, as is known in knitting. This supply spool 20 periodically replenishes its yarn supply and ensures constant yarn takeoff tension.
The marking thread 13 is taken off the supply spool 20 by the motion of the tubular felt 3 and is deposited by guide plate 21, having guide grooves, onto the tubular felt 3 and directly thereafter is fastened by the needling machine 11. This arrangement assures that the marking thread 13 always is deposited at the same place and with the most uniform possible takeoff tension on the tubular felt 3.
The takeoff device 14, shown in FIG. 7, includes a base plate 22 rotatably supporting a takeoff spool 23 driven by a drive motor 24. The marking thread 13 passes from the (omitted) tubular felt 3 into the takeoff device 14, through slotted eye 25, fixed eye 26 and eye 28 which is guided in displaceable manner in the transverse direction on a rail 27, and finally arrives at the takeoff spool 23. The eye 28 is displaced from time to time so that the marking thread 13 is wound uniformly across the width of the take-off spool 23.
The drive motor 24 is set in such a manner that more marking thread 13 will be taken off by the takeoff spool 23 than is required. Due to the tension exerted, the marking thread 13 moves into the position 13a shown in dashed lines. When in that position, a switch 30 is actuated by sensor 29 which turns off drive motor 24 whereby the marking thread 13 no longer is wound onto the takeoff spool 23. Soon the marking thread 13 assumes the position 13b shown in solid lines wherein it actuates the actuator 31 of switch 32. This switch 32 turns on the drive motor 24 whereby the marking thread 13 is rewound. In this manner, the marking thread 13 is removed in a problem-free manner from the tubular felt 3.
The block circuit diagram shown in FIG. 8 discloses a detector circuit 33 for an analyzer, shown in further detail in FIG. 9, and which is connected to the video camera 15 of FIG. 1. The image projected on the vidicon tube is resolved conventionally into 625 scanning lines, with every second line being scanned sequentially. Therefore, one image is resolved into two half-images and transmitted.
The video camera 15 emits a video signal, the voltage of which is proportional to the image part that was just scanned. As already described above, the video camera in this instance is arranged in such a manner that the marking thread 13 runs parallel to the scan lines, whereby the marking thread is scanned by the vidicon tube as darkened lines thereby generating a corresponding video signal. Additionally, the video camera 15 provides pulses which, on one hand, indicate the beginning of the scanning of a half image, the so-called image sweep pulses, and, on the other hand, signals the beginning of the scanning of a line, namely the so-called line sweep pulses.
The detector circuit 33 includes a shift register 34, the input of which is fed with line sweep pulses F. By means of a parallel conductor 35, the line sweep pulses simultaneously synchronize the shift register 34. The image sweep pulses G are fed into another input of the shift register 34. These image sweep pulses 34 reset the shift register into a defined initial state when a half image is being scanned. The video signal H first arrives at an amplifier 36 and then at a threshold-value switch 37. This switch causes gate 38 to be conducting the moment a video signal H is received that has scanned a dark line originating from the marking thread 13. Once the gate is conducting, a line sweep pulse F arrives in the shift register 34. If the next scanned line also is dark, the next line sweep pulse F also is fed into the shift register. Again, the same operation takes place if the third scanned line also is dark.
An AND gate 39 connected to the shift register 34 only transmits a signal when at least three consecutive line sweep pulses F have been moved through the shift register 34. The output signal then means "marking thread recognized". After the first half image has moved through, the shift register 34 is reset by the image sweep pulse G and now is ready to receive line sweep pulses F from the second half image. Accordingly, the gate 38 is made conducting again for the line sweep pulses F the moment a video signal H from the scanning of dark lines is present. Therefore, one output signal is generated for each half image behind the AND gate 39.
FIG. 9 is the block circuit diagram of the entire analyzer, with the detector circuit 33, however, being indicated in this figure only as a single block. The line sweep pulses F pass through a conductor 40 into a gate 41 and from there into a line sweep pulse counter 42 where they will be counted, provided the gate 41 is conducting. The gate 41 is controlled by a multi-position switch 43. For the shown position of the multi-position switch 43, the gate 41 is permanently conducting. In this manner, all the line sweep pulses F arrive at the line sweep pulse counter 42.
If the multi-position switch 43 is moved to the right by one position, the gate 41 will be controlled by a counter flip-flop 44. This counter flip-flop 44, on one hand, receives through the conductor 45 the image sweep pulses G. These pulses G control the counter flip-flop 44 and make the gate 41 conducting. Accordingly, at the beginning of every half image the line sweep pulses F can arrive at the line sweep pulse counter 42.
The gate 41 remains conducting until the detector circuit 33 emits a control pulse to reverse the counter flip-flop 44. As more closely discussed in the description of FIG. 8, this takes place every time three dark lines have been scanned and the associated line sweep pulses F have been moved through the shift register 34. After the counter flip-flop 44 has been reversed, the gate 41 will be blocking and therefore no more line sweep pulses F are received by the line sweep pulse counter 42. The moment a first half image has been scanned, the counter flip-flop 44 is reversed again by the image sweep pulse G and thereby the gate 41 is made conducting again. Presently, the line sweep pulse counter 42 receives a number of line sweep pulses F until the detector circuit 33 once more displays "marking thread recognized" and generates a corresponding signal to reverse the counter flip-flop 44. Presently, the line sweep pulse counter 42 receives the line sweep pulses F from both half images generated from the beginning of each half image to the scanning of each three dark lines. The sum of these two series of line sweep pulses F then is a measure of the position instantaneously assumed by the marking thread 13, that is, whether it has been moved too much or too little in the transverse direction.
A data flip-flop 46 is connected in parallel with the counter flip-flop 44. This data flip-flop 46 is connected by the multi-position switch 43 to the gate 41 when the spacing between two marking threads must be detected. For that purpose, the data flip-flop 46 is moved by the image sweep pulse G through the conductor 45, by the counter flip-flop 44 and the conductor 47 into a defined position at the beginning of each half image, the gate 41 being blocked in this position. The line sweep pulse counter 42, therefore, first receives no line sweep pulses F. The data flip-flop 46 is reset only by an output pulse from the detector circuit 33 which then makes the gate 41 conducting. As described above, this takes place when three dark lines have been scanned, that is, when a first marking thread has been detected. When the image recorded by the video camera is further scanned, the second and adjacent marking thread will next be detected by again scanning three dark lines, whereupon a corresponding output signal to reset the date flip-flop 46 will be generated in the detector circuit 33. This resetting causes the gate 41 to be blocking again. The line sweep pulse counter 42 thereupon has counted only those line sweep pulses F which occurred between the two adjacent marking threads recorded by the video camera. It must be added for the sake of accuracy that the first three line sweep pulses F generated upon detecting the second marking thread are included in the count. In this case too, the line sweep pulses F from both half images are summed in the line sweep pulse counter 42.
The line sweep pulse counter 43 is connected to a line sweep pulse memory 48 which receives the count from the line sweep pulse counter 42 after two half images have been scanned. This is implemented by means of another counter 49 receiving the output from a high-frequency multivibrator 50. The image sweep pulses G pass through a conductor 51 into the counter 49, with a 2:1 divider 52 being inserted. The divider 52 assures that only every second image sweep pulse G arrives at the counter 49.
When an image sweep pulse G is present, the outputs of the counter 49 are so controlled by the count of the pulses of the astable multivibrator 50 so that a transfer pulse is fed through the conductor 53 to the line sweep pulse memory 48. The count from the line sweep pulse counter 42 then passes into the other. Thereupon, a reset pulse passes through the conductor 54 into the line sweep pulse counter 42 which thereby is reset to zero. Thereupon, the counter 49 blocks itself from further counting. The high frequency of the multivibrator 50 causes this to occur so rapidly that the transfer of the count magnitude and the resetting of the line sweep pulse counter 42 is terminated before the first line sweep pulse F following the image sweep pulse G is received.
The line sweep pulse memory 48 is connected to three outputs, the first of which leads to a digital display 55 of the count magnitude in the line sweep pulse memory 48. The second output forms the binary output for the subsequent regulator 56 while the third output leads to a digital-analogue converter 57 which controls, for instance, a plotter.
A conductor 58 is connected to the conductor 53 in order to feed synchronizing pulses to the computer shown in FIG. 10.
FIG. 10 discloses the circuit-diagram in block form of the regulator for the PI control which controls the drive of the conveyor chains 5,7, as best shown in FIG. 2. The drive can be controlled so that the actual transverse motion of the tubular felt 3 corresponds in as constant a manner as possible to a specific reference value. Due to the high time-constants of the controlled system, a microprocessor-based computer is inserted in the controlled system. Appropriate software controls this microprocessor 59.
The reference value for the transverse motion of the tubular felt 3 is pre-set by means of a switch 60. Switch 60 is connected to relay 61. Relay 61 at the time is in a position connecting the switch 60 directly with a current rectifier 62 for the drive motor of the conveyor chains 6,7. This drive motor, not shown in further detail herein, therefore is not controlled at this very instant, rather it receives only the prestored reference value. This prestored value is fed to the current rectifier 62, particularly when the microprocessor 59 is turned off or when spurious effects have taken place.
The position of the switch 60, and hence the reference value, is then read into the microprocessor 59 through an optical coupler 63, an input multiplexer 64 and an input port 65. After the setting value has been computed, it is fed through the output port 66, the output multiplexer 67, the optical coupler 63 and the relay 61 to the current rectifier 62. Before that, however, the relay 61 must be moved into the automatic position, and, this is performed by using control circuit 68.
The control circuit 68, on one hand, is controlled by another detector circuit 69 which signals to the control circuit 68 whether the needling machine 11 is operating or not. In the latter case, the control circuit 68 causes the microprocessor 59 to cease computing any new setting value. Furthermore, the control circuit 68 is also controlled by an operating means 70. This operating means 70 can be used to manually reverse the relay 61, for instance to interrupt the operation of the microprocessor 59. Furthermore, the operating means 70 is used to transfer the regulation factors for the P and I parts to the micro-processor 59. They must be matched to the time constant of the controlled system determined by the length of the tubular felt and its circumferential speed. A selection circuit 71 is provided to read-in the regulation factors and is connected through an input port 72 and output port 73 to the microprocessor 59. The operating means 70 is further connected through an input port 74 to the microprocessor 59 so that a start pulse can be fed to the microprocessor 59 to set it into a specific initial position. Another switch causes the control circuit 68 to switch the relay 61 into the automatic position.
The analyzer 75, shown in further detail in FIGS. 8 and 9 in this instance, is represented merely by a block. The binary output 56, shown in FIG. 9, passes from this analyzer 75 into a buffer stage 76 transmitting the count of the line sweep pulses F through the input port 77 to the microprocessor 59. Each newly ascertained value triggers an interrupt 78 whereby the microprocessor 59 is notified that the count magnitude is present for a given time interval and in stable manner at the input port 77.
Each second the microprocessor 59 reads-in one value, having previously awaited the synchronizing pulse from the counter 49 of FIG. 9, specific checks can be carried out using corresponding software before the microprocessor 59 does compute a setting value. This includes, in particular, checking whether in fact a marking thread is present within the camera range. If this is not the case, an operational discontinuity takes place in an alarm loop having a corresponding display and ensuing programming termination. If the checks show that the microprocessor 59 must compute a setting value, then the count magnitudes of the line sweep pulses fed to the microprocessor 59 first are compared with the corresponding predetermined reference value and the difference is formed. Then the proportional and integral values are obtained and thereafter the setting value is computed. This is followed by a conversion of the binary value initially present in binary form into a BCD value which then appears on the output. Lastly, reset takes place and the wait for the second synchronizing pulse. | A method and apparatus for producing an endless tubular felt includes superposing layers of tubular felt one upon the other and binding of the superposed layers together. A marking line is applied to the top surface of the superposed layers in continuous manner as the felt is trained about the driven rolls. The rolls include needle segments which move the felt axially of the roll. A scanner scans the position of the marking line shortly before the completion of one revolution. A controller compares the position of the marking line with a reference and causes the needle means to be adjusted to that the marking line corresponds with the reference. | 3 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a national stage application and claims the benefit of the priority filing date in PCT/RU2010/000449 referenced in WIPO Publication WO/2011/019303. The earliest priority date claimed is Aug. 13, 2009.
FEDERALLY SPONSORED RESEARCH
[0002] None
SEQUENCE LISTING OR PROGRAM
[0003] None
STATEMENT REGARDING COPYRIGHTED MATERIAL
[0004] Portions of the disclosure of this patent document contain 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 file or records, but otherwise reserves all copyright rights whatsoever.
BACKGROUND
[0005] 1. Sphere of Invention
[0006] This invention relates to X-ray engineering and medical diagnostics which deal with techniques of imaging and visual representation of X-ray radiation in the energy range of 5 keV to 200 keV. In particular, this invention may be useful in medicine for the control and monitoring of pathological changes in a living body. This field of medicine, known as radiology, dates back to the beginning of the XX century when German physicist C. Rontgen discovered penetrating radiation named after him.
[0007] This invention can also be practicable for dynamic stream preventive examination of patients where the main task is to reveal major pathologies. The invention may also be used in dentistry which requires X-ray examination of the dentofacial area. Another important role the invention may play is in the field of mammalogy for the examination of mammary glands in women.
[0008] In addition to medicine, the invention may be useful in defectoscopy and in non-destructive examination systems in various areas of mechanics, such as weld examination in pipelines. The invention is of particular importance for the quality control of fully armed munitions where the technique is possibly the only way of stream quality control.
[0009] The invention may be used in the customs control of dimensional cargo in railroad, air and sea transportation.
[0010] Such wide area of possible usage of the invention may be explained partly by the need for non-destructive quality control and diagnostics and is an unusual combination of state-of-art materials comprised of scintillators with matrix-type semi-conductor systems for information reading, computer processing and archiving. Undoubtedly, the invention involves advanced technologies.
[0011] 2. Current State of Technology
[0012] The first X-ray apparatuses were made in the 1920s and comprised an X-ray emitting source and a radiation receiver. Since then, no major changes were implemented in X-ray emitting sources: a vacuum device's high-energy accelerated electron beams bombards a metallic anticathode made of tungsten (W) molybdenum (Mo), or sometimes, of copper (Cu). Emerging impact X-ray radiation is filtered to make it monochromatic and then escapes the device through special materials which are penetrable by radiation type (such as beryllium foil). The resulting X-ray beam has a diameter of several millimeters to ten centimeters. Impenetrable structures or bodies requiring examination are placed into this beam.
[0013] For a long time, the only way of visually imaging a change in X-ray quantum density in a beam was by a photoemulsion detector based on silver halides. But due to the relatively low density (2-3 g/cm 3 ) of detecting layers and the low sensitivity of silver halides to X-ray radiation, this method required high exposure to X-ray radiation, thus limiting medical usage.
[0014] The first technical solution aimed at significantly lowering the exposure dose for X-ray examined patients were X-ray intensifying screens. These screens allowed for a physical shift of quantum energy. A screen was basically a thin layer of a substance—X-ray luminescent material—which radiated when exposed to X-rays. A screen was usually made in the form of a cassette comprising front and rear screens and a photo-sensitive film. The front screen had a thinner layer of X-ray luminescent material and the rear screen was aimed at stopping X-ray radiation almost completely.
[0015] For a long time, the main material of X-ray luminescent materials in the intensifying screens was calcium tungstate (CaWO 40 which features a high gravitational density and a medium energy conversion efficiency (6.0-8.0%). These parameters were used as a reference for optimal, compounds of X-ray luminescent material. The basic requirements to these compounds were as follows:
[0016] average atomic number N in excess of 40 atomic units;
[0017] gravitational density in excess of 4.5 g/cm 3 ;
[0018] energy efficiency of X-ray luminescent material emission>6%;
[0019] back-glow less than 1*10 −3 sec;
[0020] spectral maximum of radiation λ>400 nm.
[0021] Radiology based on direct interaction between X-ray radiation and living tissues (in medical X-ray diagnostics) or between X-ray radiation and parts of complex systems and structures (in X-ray defectoscopy) allowed for the following imaging characteristics in photo-sensitive film or translucent screens:
[0022] resolution 1-0.6 mm per pair of lines;
[0023] contrast with a ratio between dark or light fields and background below 30%;
[0024] imaging of tiny details of 650-800 μm in size;
[0025] after-glow period around 1·10 −3 sec.
[0026] It should be noted that the radiation stress of a patient was excessive even for the state-of-art techniques at the time (1.0 to 10.0 Roentgen units per examination of gastrointestinal tract) [1].
[0027] The low characteristics of X-ray diagnostics in 40-70-s necessitated the development of new methods of diagnostics based on other physical principles; thus, in 1964 [2] the first X-ray electron-optical image converting systems (EOIC) were proposed, which managed, the primary conversion (transduction) of X-ray radiation to visible light with further multiple intensification and transformation of the light signal into small picture frame television images [2]. Transducers of the first EOICs were based on halogenide luminescent materials, such as water-soluble cesium iodide, which made the production technology of equipment significantly complex.
[0028] At the same time, a method of rapid X-ray photoroentgenography was developed which involved the projection of an image formed on a large translucent luminescent screen onto photographic film by means of a large aperture lens system. This method became convenient for applications where many patients required examination in a short period of time. Photoroentgenography resulted in the discovery of large niduses only.
[0029] Beginning in the mid-70-s, the era of rear-earth X-ray luminescent materials began [4], first with primary oxysulfides (Y 2 O 2 S:Tb, Gd 2 O 2 S:Tb), and then with oxybromide (LaOBr). The main achievements and challenges of this period of material and screen development are summarized below [5].
[0030] This period of rapid development of materials for radiography brought important scientific results, in particular, the requirements adjustment to the chemical bonding of an X-ray luminescent matrix, as well as the achievement of good experimental results with visual light energy output efficiency under X-ray or gamma-radiation (e.g. 22% for Y 2 O 2 S:Tb which paved the way to a new level of knowledge.
[0031] Comparison, in the La 2 O 3 —La 2 O 2 S—LaOBr:Tb row shows a significant impact in covalent-type bonding in luminescent matrices, which previously had mostly ionic bonding. Research results and certain generalizations [6] may be summarized in the following table of optimum parameters for X-ray luminescent materials.
[0000]
TABLE 1
Wavelength
Maximum
Atomic
Energy
of spectral
range of
After-
number,
Density,
efficiency,
maximum,
radiation
glow,
Composition
N
g/cm 3
%
nm
hardness keV
ms
CaWO 4
61.8
6.1
6-9
420
80-100
1-1.5
ZnCdS:Ag
38
4.8
14-18
560
80-90
1-2
CsJ:Tl
41
4.2
12-18
550
80
0.001
Y 2 O 2 S:Tb
36
4.95
21-22
383.478
60-70
1-3
Gd 2 O 5 :Tb
59.9
6.00
20-24
545
100-120
1-3
LaOBr:Tb
49.3
5.7
18-20
543
80-110
1-2
[0032] Most notably, this period of radiology development resulted in a 3-4 time decrease of radiation stress on patients, especially in children. Along with this, a significantly higher ratio of X-ray absorption from new X-ray-sensitive materials results in the rejection of traditionally used X-ray screen coarse-grain materials and the utilization of medium-grain materials which increase the resolution of intensifying screens by 20-40%. This was enough to allow the naked eye to see calcified focuses in the mammas of women. This was the beginning of mammography as a preventive field of practical radiography.
[0033] At the same time, PHILLIPS proposed using new column X-ray-sensitive coatings (CsJ:Tl) in the screens of EOICs, which had the advantage of not dispersing light due to the light-conducting properties of column microcrystalls of the cesium iodide. The image quality of these apparatuses was as high as in succeeding serial apparatuses which had screens with gadolinium oxysulfide. EOICs allowed for the observation of interaction between soft tissues with X-ray contrast substances, such as barium sulfate or tantalic gadolinium (GdTaO 4 ) ( FIG. 1 ) to reveal ulcerous focuses or other pathologies in a patient's body. The brightness of screens in X-ray devices was improved and reached a threshold of direct registration (brightness level 2-3 cd/m 2 ) by means of an optical image transfer and/or intensifier also based on CCD-matrix [6].
[0034] At the same time, it allowed for a decrease in, the energy limit of registration for soft X-ray radiation featuring an energy of E=100-1000 eV. This technology was later used in deep-space apparatuses [6].
[0035] The production of highly sensible CCD-matrixes with 10 −2 lux of light threshold started the development of advanced digital X-ray-sensitive devices [7] which form images with a brief delay during patient examination.
[0036] This new stage of real-time radiography development lasts until today. This stage involves:
[0037] improvement of dispersiveness of the most effective material based on Gd 2 O 2 S:Tb [8];
[0038] selection of compositions based on this luminescent material [9];
[0039] creation of X-ray microdetectors [10];
[0040] improvement of silicon matrices [11];
[0041] creation of the first types of digital X-ray detectors [12];
[0042] digital X-ray detector [13];
[0043] utilization of white reflecting coatings based on Ta 2 O 5 in [14];
[0044] utilization of optically transparent ceramics based on Lu 2 O 3 Eu in the new detector [15].
[0045] The most recent publication on this topic is an article by Korean scientists [16] who proposed the construction and production technology of a multi-element X-ray sensitive layer of Gd 2 O 2 S:Tb in polyethylene press-work having elements coated with reflecting film made of Cr—Al (6000 Å thick). The authors noted a 1.5-2 time decrease in the X-ray luminescent material radiation compared to the solid layer of luminescent material. Yet, the modulation transfer function in the image formed on the structured X-ray sensitive screen is somewhat higher with several extrema of the frequencies close to the geometrical dimensions of screen elements.
[0046] Despite some advantages in the detector described in [16] such as a decrease in overall X-ray radiation which falls into a pixelled (multi-element) scintillator only, this construction has several major disadvantages:
[0047] reduction of radiation intensity of multi-element screens made of Gd 2 O 2 S:Tb;
[0048] shallow thickness of X-ray luminescent material allowing for X-ray radiation to reach photodiodes directly causing their degradation;
[0049] complex production of microscopic multi-element detectors due to the utilization of the photolithographic process; thus, the original article cites only a small sample of the screen 2 by 3 cm in size;
[0050] low contrast of the image on a scintillator; to enlarge the image, the scintillator is additionally covered with a blackening graphite grid;
[0051] the shallow thickness of Gd 2 O 2 S:Tb luminescent material allows for the use of low accelerating voltages in the X-ray tube only, e.g. 45 keV, which is suitable for limited application only, for example, in dentofacial examination.
[0052] These disadvantages were considered in the publication [17] which we used as a prototype for our invention in which the authors suggest a return to radiation sources made of CsJ:Tl with columns of 4-7 μm thick. Elements up to 16 mm high comprised of such structures were used to create a complete scintillator. The authors claimed that such a detector had a modulation transfer function MTF=40% at a resolution of 4 pairs of lines per mm and a MTF=10-20% at a resolution of up to 8 pairs of lines per mm along with an image contrast decrease.
[0053] Despite some advantages presented by high quantum detectivity DQL=0.28, the authors suggested that use of CsJ:Tl is not necessarily effective due to defects in microcrystals. With all this, as the authors insist, the intensification of patient radiation stress may be only partly justified by the high definition of the detector.
[0054] Despite the various advantages of the prototype detector, such as high quantum detectivity which is singularly prominent at low energies, the prototype had many significant deficiencies. First of all, it has a narrow range of exciting energy of X-ray radiation from 35 keV to 60 keV which is insufficient for a complete medical examination. The second issue is that the radiation load may reach high values of ten roentgens, especially if complex pathologies are to be examined, or if X-ray contrast substance is used. Third, due to the small size of each of the structural elements of the detector (16 mm), the resulting image would be fogged because of the discontinuity of each element.
[0055] Fourth, the hidrophylic behavior and temperature-sensitive character of cesium iodide CsJ:Tl requires a comprehensive sealing of detector elements and protection from moisture, which poses a complex problem in view of the elements' tiny size.
[0056] Fifth, it should be noted that the production of column structures of CsJ along with interaction with extremely toxic thallium Tl is a very complex and environmentally-prone problem that may be solved by the use of advanced-technology rooms with closed-circuit atmosphere and induced air.
[0057] Thus, the series of disadvantages of the existing X-ray detector design, such as the narrow energy operating range, the discontinuity of the imaging field, the low hydrolytic stability and the durability, creates a need for the proposed X-ray detector.
OBJECT OF INVENTION
[0058] The main object of the invention is to create a multi-element X-ray detector featuring a high contrast of integral images and information reading by means of a matrix system of silicone photodiodes. Another object of the invention is to create a wide range of X-ray energy devices capable of operating under various voltages in an X-ray emitter (tube). One of the main objects of the invention is to create a set of multi-element detectors with different resolutions but with equal contrast and contrast transfer parameters.
[0059] A very important challenge in developing the invention is the evolution of a single process cycle of production for the multi-element detector independent of its geometrical dimensions.
[0060] Another challenge in developing the invention is to explore the possibility of manufacturing a universal multi-element detector for several types of penetrating radiation, such as low-energy X-ray radiation (below 10-15 keV), gamma-radiation (energy value 150-250 keV) and slow neutron beams (energy value E=0.1 eV to 1-2 eV).
SUMMARY
[0061] To reach the above-mentioned objectives and challenges we suggest a novel construction of a matrix X-ray detector which consists of a flat multi-element scintillator necessary to transform X-ray radiation reaching the external surface of the scintillator into visual light, and a photodetector matrix which transforms the luminescent radiation of the inner surface of the scintillator into an electrical signal. This detector differs from others with a luminiscent scintillator construction, in that it is made as a discrete set of hetero-phase luminescent elements arranged in cells of a grid made of X-ray-absorbing and visual light reflecting metal. The spacing, cross-section and interconnection dimensions of the aforesaid grid are equal with the dimensions of each particular luminescent element and coincide with the actions of the photodetector matrix, while the rear surface of the grid has a reflecting layer and the front surface is covered with a multi-element photosensitive semiconductor matrix. Each element of this semiconductor matrix is optically in contact with elements of the luminescent detector, and they are simultaneously excited by the X-ray radiation in the energy range of 30 to 140 keV.
FIGURES
[0062] FIG. 1 shows the intensity dependence of X-ray luminescence for various compositions which comprise Gd, O, S, Ta, Lu ions. The energy peaks on the inner K-orbits of the substances' electrons are apparent.
[0063] FIG. 2 shows the construction arrangement of the proposed device which shows that the device comprises a multi-element scintillator 1 consisting of an orthogonal metal grid made of interlaced wires 2, and the grid's cells 3 contain hetero-phase elements 4 bearing luminescent glowing materials seen under X-ray radiation (X-ray luminescent material). The inset in FIG. 2 shows the structure of one grid cell. There is a hetero-phase scintillator element 4 in the cell; this element is made of polymer 5 transparent to light with grains of X-ray luminescent material 6 spread all over its surface. The matrix 7 of semiconductor photodiode elements is connected to the inner surface of the scintillator; this matrix bears silicon photodiodes 8 and a system of control electrodes impregnated into the baseplate 9. The external surface of the scintillator has a double-layer reflective coating 10 which is transparent to X-ray radiation and is 0.6 mm thick. The cover glass 12 is used as a bearing structure which fixes all operational layers of the detector with polymer coating 11.
[0064] FIG. 3 shows cast film coatings for the X-ray scintillator.
[0065] FIG. 4 shows the microphotography of a single grain of X-ray luminescent material used.
[0066] FIG. 5 shows a photo of the screen of the proposed detector.
DETAILED DESCRIPTION
[0067] We shall now further briefly describe the physical features of the proposed matrix detector, which is based upon a metal grid filled with X-ray luminescent material. As we have established in prior optical testing, the metal grid divides the solid layer of luminescent material into a mosaic multi-element pattern and significantly increases the contrast of detector imaging (1.5-2 times).
[0068] The stated difference is achieved by an X-ray detector with an X-ray-sensitive layer having a mosaic pattern shaped in an X-ray luminescent material layer by a grid made of metal having atomic numbers 24 to 74.
[0069] Let us consider the physical processes of the device. A full-wide beam of X-ray radiation reaches its front surface. This beam is emitted by a vacuum X-ray tube with an alternating anode voltage U=60 keV to 125 keV and a working anticathode made of Mo. X-ray radiation emitted as a result of electron beam deceleration escapes the tube through a vacuum-tight window shielded with beryllium foil. High-energy X-ray radiation penetrates a reflecting layer of the detector's surface and reaches the X-ray luminescent material grains.
[0070] This original X-ray radiation causes primary K-electrons in the luminescent material grains and then collective energy oscillation—plasmons which further disintegrate into electron-hole pairs (e+p) to directly interact with ions of activators and sensitizers of the X-ray luminescent material grain. The distance which the primary X-ray quantum travels in the scintillating target is 20 to 200 μm depending on the initial energy E x-ray and density of the X-ray luminescent material used. It is known that luminescent material made of Gd 2 O 2 S:Tb with density of ρ=6.6 g/cm 3 (the quantum with energy E=60 keV) penetrates to the depth ε=0.1p×d av =0.1×6.6×10=40 mg/cm 2 . If the initial energy of a quantum is E=120 keV, then the penetration depth is 160 mg/cm 2 .
[0071] As we will show later, the technical solution is a reduction of the fully required penetration depth of up to 100 mg/cm 3 for the working values of X-ray quantum energy.
[0072] Excited active ions (activator) in the bulk of the X-ray luminescent material usually gets ionized under the effect of the electron-hole pair i.e. changes its oxidation degree. Thus, active ion Eu +3 absorbs an electron:
[0000] Eu +3 +e →Eu +2* +p →Eu +3 *→Eu +3 (5D J .7FJ)
[0000] with emissions of red quantum with wavelength λ=626 nm to λ=710 nm. The possible number of quanta emitted by the X-ray luminescent material is N=Ep/hωpr, where Ep-initial is the energy of a quantum, hωpr-energy of plasmon.
[0073] As we have shown before, a more exact quantity of quanta allows for the value of a linear-cluster plasmon hωpl and not for the value of a bulk plasmon hωpr. According to our adjustment, the more the atomic mass of the elements of a cluster, the less energy is required to excite such cluster. Thus, the X-ray luminescent material Gd 2 O 2 S:Tb is the value hωpr=16-20 eV, while in the proposed material (Gd,Lu) 2 O(Br,N)S, the value of a linear cluster decreases down to hωpl=14.8 eV, indicating a significant increase in effectiveness of the novel luminescent materials proposed in the patent claim.
[0074] A quantum of visual light generated in the X-ray luminescent material has an energy value hν=2.1 eV to hν=1.85 eV. Each X-ray luminophore emits a quantum uniformly, filling 4π space. To increase the degree of light channeled to the photosensitive elements of the detector, the invention assumes coating the external surface of the detector with reflecting Al film 0.1 to 0.6 mm thick, which enhances the glowing brightness of the detector elements by 40-0.60%
[0075] The aforesaid advantage is realized in a multi-element detector which features a rear side coated with a double-layer reflecting metal film 2000 Å to 6000 Å thick, with a detector covered with metal silver up to 1000 Å thick with an overlaying aluminum coating up to 5000 Å.
[0076] As we revealed during the development of the invention, the albedo of the proposed double-layer film is 88-92% against 82% of a single-layer Al coating which is conveniently used in electron tube devices.
[0077] Moreover, to enhance light concentration in the detector, we propose coating wires, which are the base of the detector grid structure, with Al (vacuum process) or Ag (electrodeposition or vacuum process). As we have practically proved, this produces up to 10-15% of light in excess compared to the unstructured layer of a photodetector.
[0078] This advantage is realized in the proposed design of a detector with grid turns coated with a reflecting metal layer of silver up to 2000 Å thick formed by electrodeposition or under vacuum deposition process.
[0079] Characteristics of Grids Used in the X-Ray Detectors.
[0080] Furthermore, we provide the basic parameters of the metal grid. First, a grid is a structure element made of intercontacting metal wires located perpendicular to each other. Through the manufacturing process, the grids may be woven, which are produced in a weaving loom; thus having basic wire and weft perpendicular to it. A grid is designated by number which shows the quantity of base wires per 1 centimeter of the grid. Along with this value, the rated diameter of the wire used is usually expressed in millimeter fractions. Another important parameter of a grid is the grid size “in the light,” i.e. the linear space which is not filled with the wire turns. If the area of such space is considered, then this parameter is called “live cross-section in %”.
[0081] As an example, let us examine parameters of a woven grid N20. This grid utilizes one base wire and one weft wire with an equally rated diameter 0.10 mm. The grid size in the light for this wire is 0.400 mm in the base. The “live cross-section” of a square cell is estimated as 64%, which means that this grid lets 64 percent of light or penetrating radiation pass and fall on its surface.
[0082] It should be noted that such a high value of the “live cross-section” is an extremely important feature of the proposed design for a multi-element detector. Basically, the “live cross-section” values of the metal grids are around 25% to 50%. In rare occasions, for example, in a grid N1 made of 1 mm wire, such grid has a cell size in light of 9 mm and a “live cross-section” of 81.90%. But as explained below, such coarse grids are difficult to utilize in the proposed invention due to the deterioration of the detector's resolution ability.
[0083] A grid is usually delivered in reels, rolled in a cylinder. After the reel is unwound, the grid is to be mechanically flattened and the required pieces are cut out. The type of X-ray control for which the detector is intended determines the properties of these pieces. In our tests, we picked out grid sheets with 64*64 elements, 128*128 elements, 256*256 elements, 512*512 elements and 1024*1024 elements in the light. Accordingly, the linear dimensions of the elements with N20 grid were 25.6*25.6 millimeters, with an area of live cross-section of S=25.6*25.6*0.64=419.43 mm 2 . The cell dimensions and the “live cross-section” areas for the rest of the testing elements may be calculated similarly.
[0084] In the course of developing the invention, we determined that the main criteria of the utilized grid parameter improvements are the following two:
[0085] the maximum area of the live cross-section, expressed in percents;
[0086] the optimum number of base lines per 1 running mm of the grid length.
[0087] If these parameters are in place, the resolution ability of the detector may reach above 3 pair of lines per millimeter.
[0088] This is another significant advantage of the proposed detector with a detector's X-ray sensitive layer having a cellular multi-element structure based on a woven, coiled or electrodeposited grid with a “live cross-section” area above 48%, typically above 61%, and the number of wires per length unit of base above 3 per millimeter.
[0089] A review of industrial catalogues of metal grids showed; that the maximum area of a “live cross-section” is 60-64% with 2 to 4 wires per mm. During the invention's development, we proposed a metering circuit for determining the information and brightness parameters of the multi-elemental detector. This circuit comprised an X-ray source, test-objects (sheets of metal grid made of different diameter wires), and elements of the detector coated with luminescent material. The X-ray radiation energy used in the test was 45 keV. The quantitative characteristics were arranged in a selection matrix which included the measurement results of the glowing brightness of a scintillator's inner surface and the linear size of the black-to-white border in the image.
[0090] The following relationships were determined for the proposed scintillator:
[0091] if the wire's diameters are equal, then the glowing brightness is proportional to the “live cross-section” of the metal wire;
[0092] if the wire's diameters are equal, the brightness intensity decreases proportionally to the number of metal grid turns per 1 millimeter;
[0093] an increase in the number of metal grid turns results in an increase in intensity of background light noises in the working field of the detector.
[0094] Thus, we suggested the following types of metal grids should be used in a multi-element detector:
[0095] woven grids made of various metals, starting with stainless steel, yet with the main element of alloy is iron Fe with an atomic number 24 and then brass, bronze or tombac alloys based upon copper with an atomic number 29;
[0096] electrodeposited grids with the main element of material nickel Ni with an atomic number 28;
[0097] coiled grids made of extremely thin tungsten wire; the main element is tungsten with an atomic number 74.
[0098] Mechanical and optical properties of the grids are presented in the Table 2 below.
[0000]
TABLE 2
Grid Size
‘Live cross-
Atomic
(turns per
section’,
Hardness,
Grid Type
Material
Number
mm)
%
%
Woven
Stainl. steel
26
2-4
Up to 64%
100
Bronze
29
Electrode-
Nickel
28
20-40
Up to 80%
50
posited
Coiled
Tungsten
74
40-60
Up to 85%
200
[0099] As we revealed in developing the invention, any of the metallic grid sheets results in improving imaging contrast 1.5-2 times, while coiled tungsten grids enhance this parameter 2.5-3 times.
[0100] The stated advantages of significantly enhancing imaging contrast are realized in a detector featuring woven metallic grid sheets made of stainless steel, nickel or bronze with a “live cross-section” of up to 64%, as well as coiled tungsten grids with a “live cross-section” of up to 85%.
[0101] X-Ray Sensitive Luminescent Materials for the Detector.
[0102] Single-phase luminescent coatings such as column screens made of CsJ:Tl under vacuum technology are usually used in the cited literature detectors. This technology implies thermal evaporation of process material such as cesium salt CsJ doped with 5% of thallium Tl on a substrate. In this case, luminous transmission, which is the preferred distribution of visual light, provides significantly different refraction indices of cesium iodide (n≈2) and medium—typically, atmosphere air (n≈1). Such double difference of refraction indices allows for luminous transmission in elements as little as 40-50 μm. The only drawback of such column structure is the appearance of gas bubbles and microscopic inclusions during coating.
[0103] We propose another structure of a detector which provides for no optical interaction between its X-ray-sensitive layer elements by means of placing each of the laywer elements into a casing composed of metal grid coils. In this case, we propose filling the space between the luminescent grains with a polymer transparent to light; this space amounts to up to 60% of the total volume of the detector. As we discovered, the hetero-phase nature of the layers ensures the minimum influence of the luminous transmission, which is a consequence of the difference in refraction indices of the X-ray luminescent grains and the polymer binder. We have also shown that the ratio between the refraction indices of luminescent material and the proposed X-ray-sensitive detector's polymer must be within the range of 1.2<n luminescent /n polymer ≦1.6.
[0104] If the refraction index of the proposed luminescent material's grains (composed of gadolinium-lutetium-europium) is n=2.2, then the upper limit of this inequality is determined by the optical properties of the polymers used, which typically have low refraction indices. Thus, methylmethacrylate has a refraction index n=1.45. Well-known organosilicon polymers have n=1.45-1.55. Optical epoxy polymers have n=1.56. We suggest using an X-ray-resistant polycarbonate in the invention with a refraction index n=1.59-1.60 and optical transparency of, about 91-92% in the visual spectrum. In this case, the light propagation in the hetero-phase medium comprised of polycarbonate polymer and X-ray luminescent material increases 2.3 times or, if luminescent material is taken in optimum concentration, 2.8 times.
[0105] This significant advantage of the X-ray sensitive layer is realized in a detector featuring a disperse medium composed of a polycarbonate with a refraction index n=1.59-1.60, which encapsulates a disperse medium of rear-earth X-ray luminescent material with a refraction index n=2.2.
[0106] As we have also discovered in our work, an increase in the polymer volume concentration of the detector's hetero-phase material results in additional luminous transmission or luminescent material radiation channeling, while an excessive increase in the volume concentration of the polymer in the hetero-phase medium above 75-80% has an adverse effect. This is the result of a decrease in the detector element's X-ray radiation intensity along with an increase in the volume concentration of polymer in the hetero-phase detector. Table 3 shows data on the dependence between the detector's radiation intensity and the volume concentration of translucent polymer, which implies that the optimum concentration for producing an X-ray sensitive layer is the ratio of 2- to 60%
[0000]
TABLE 3
Detector
Polymer Volume Concentration, %
Characteristics
10
20
30
40
50
60
70
80
Radiation
200
180
160
140
120
100
80
60
Intensity %
Possible
40
60
80
100
120
140
160
200
Optical
Distance, mm
[0107] Manufacturing Process of the Detecting Layer.
[0108] There are several manufacturing processes of multi-element X-ray detector production in the cited literature.
[0109] First, it's extrusion, method implies the preparation of superconcentrates from a mixture of high-density polyethylene (HDP) and luminescent material grains. These superconcentrates contain up to 20% mass of luminescent material. Then, these granules are extruded into a thin polyethylene film in a single-worm extruder. Then, this film is molded under a temperature of T=130-160° C. onto the comb structures of the detector, forming cavities required to provide a discrete layer nature.
[0110] Regardless of industrial practice of this procedure, it has significant deficiencies. Double heating of the luminescent material in the molten polyethylene is attributed to this procedure, which results in surface oxidation of the X-ray luminescent material forming an oxysulfate film of Gd 2 O 2 SO 4 . This causes non-radiating recombinations and a decrease in effectiveness of the X-ray radiation's transformation to light. To eliminate this deficiency of a widely-used process, we developed a cast process of detector formation. The following are the main features of the cast process:
[0111] use of a specially composed suspension made of a molecular dispersion of polycarbonate and luminescent material grains;
[0112] utilization of separation die hole for the starved feeding of the luminescent material suspension applied onto the grid of the detector;
[0113] utilization of a moving continuous belt with a prefixed grid sheet;
[0114] a hetero-phase polymer layer drying in infrared light which fully penetrates the layer.
[0000] The resulting detecting layer features precision thickness e.g. 40 to 120 μm.
[0115] A significant advantage is realized in the X-ray-sensitive coating of a detector featuring cast process production, which implies the distribution of a liquid-phase X-ray luminescent material suspension through a solution of polymer binder where the polymer is a polycarbonate with a molecular mass of M=10000-15000 carbon units dissolved in a low-boiling solvent, such as methylenechloride containing a powder X-ray luminescent material in suspension of about 20 to 40% of polymer mass.
[0116] We suggest using a special X-ray-stable polycarbonate as a polymer binder. This polycarbonate contains functional groups (C—O—C—O) with a polymerization number of n=150-250 and, a molecular mass M=10000-15000 carbon units. Grains of this polymer are dissolved in an organic chloride-containing solvent of methylenechloride type CH 2 Cl 2 featuring a boiling point of T biol =40.1° C. The primary suspension used for cast is prepared in a special mixer in a ratio 1:1 (methylenechloride to polycarbonate) resulting in a solution with a required viscosity of 10 to 25 centipoise. Further, a powder luminescent material is added to the solution amounting to up to 20 to 65% by mass of initial polycarbonate used.
[0117] Thus, to produce test casts we used 50 grams of pelletized polycarbonate, 50 grams of CH 2 Cl 2 and 20 grams of luminescent material grains. The suspension had a viscosity of 18-20 centipoise and was poured into a taper die made of stainless steel. The die volume was 150 cm 3 . The die was able to apply suspension to the grid sheet at the required rate controlled by microscrews. The applied layer of thickness was determined by the rate of application suspension and the speed of a moving continuous belt carrying a metal grid sheet. We determined that in a single trip of the moving belt, it was possible to make a cast coating of 20% μm (approximately 20% of the diameter of the grid wire used) to 100 μm. If a thicker coating was required, the process had to be performed twice. Before the second application, the primary coating was polymerized under the temperature of T=110-120° C. for 30 minutes.
[0118] An important feature of the suggested cast method of luminescent coating formation directly in the grid sheet bulk is a preservation of the flexibility of the overall detector structure comprised of the grid sheet with the detector's X-ray-sensitive elements inside each grid cell.
[0119] FIG. 3 shows different test elements of the detector elements. We succeeded in producing detecting layers on the grid sheets made of 100 μm wire, 120 μm wire and 150 to 200 μm wire.
[0120] The thickness of the luminescent multi-element coating of the grid sheet varied from δ=40 μm to δ=120 μm.
[0121] The full load of luminescent material in the detecting layer in this case varied from m=20 mg/cm 2 to m=80 mg/cm 2 , which is enough for absorption of the X-ray radiation of E=20 keV to E=85-90 keV. The multi-element detecting layer amounted to 80% of the grid sheet thickness (full filling) to 30% of the full thickness, and the inner surface had cavities while the external surface adjacent to the layer of silicon photodiodes remained virtually smooth without any grooving.
[0122] Novel Composition of the X-Ray Luminescent Material for the Detector.
[0123] Another field of the developed invention was the creation of a novel composition of X-ray luminescent material for the detector. According to the data on K-jumps on the inner orbitals of atoms provided in FIG. 1 , the material must contain a substance with electrons on the inner K-orbits featuring a binding energy of E K =40 keV to E K =70 keV. For this reason, we tried to use as a matrix (substrate) of luminescent material elements such as gadolinium Gd with a K-jump energy of E=56 keV and lutetium. Lu with a K-jump energy of E=61 keV. Elements europium Eu with a K-jump energy of E=54 keV and samarium with a K-enegy of E=57 keV occupy the medium position. As the supplementary absorbing element, we suggest including into the luminescent matrix element bismuth Bi with an atomic number N=83, which features a high gravitational density of ρ=8.9 g/cm 3 if presented as an oxide, allowing for an enhancement of the energy parameters under a high electron beam energy of E=120 keV. As an energy modifier of the luminescent material, we assume the addition of small quantities of rhenium oxides Re 2 O 7 with a density of ρ=8.2 g/cm 3 .
[0124] Oxygen 0 with an energy of K-jump of E=12 keV is proposed as the base ion of the anionic sublattice. As we have shown in our work, ions of fluorine, chlorine, bromine Br (N=35, K-jump energy=37 keV) and iodine I (N=53, K-jump energy=46 keV) may also be used as energy modifiers (additives promoting energy efficiency).
[0125] Thus, we propose the following composition of X-ray-sensitive luminescent material in the range of oxides Gd 2 O 3 , Lu 2 O 3 , Eu 2 O 3 , Dy 2 O 3 , Bi 2 O 3 , Re 2 O 7 for the cationic sublattice and of ions in the range O −2 , S −2 , Se −2 , F, Cl, Br −1 , J −1 for the anionic sublattice.
[0126] The most allied in the proposed composition of crystal-chemical properties are monoligand oxysulfide selenides with additionally the inserted ion-ligands of F −1 , Cl −1 , Br −1 , J −1 , N −3 group. The proposed composition of X-ray luminescent material provides energy efficiency of up to 24% (absolute) in the case of the initial energy of the X-ray beam 80 keV, while the thickness of the layer is reduced. Because the radiation spectrum of the proposed luminescent material is mainly in the red area of the visual spectrum and optimally correlates with the silicon photodetector's sensitivity, the latter generates 1.8-2 times the intensity of the current signal.
[0127] This significant advantage is realized in a detector based on an X-ray luminescent material featuring the following stoichiometric formula
[0000] (ΣMe) 2 O 2−x (ΣHal) x/2 N −3 x/2 ,S 1+y
[0128] where ΣMe=Gd and/or Lu and/or Eu and/or Dy and/or Bi and/or Re
[0129] ΣHal=F −1 and/or Cl −1 and/or Br −1 and/or J −1 ,
[0130] while stoichiometric indices are within the range:
[0131] 0.001<x≦50.08, 0.001≦y≦0.01.
[0132] The average value of the atomic number of the proposed X-ray luminescent material comprised of gadolinium (up to 50% atomic units), lutetium (up to 42 atomic units), europium (up to 6% atomic units) and a mixture of dysprosium, bismuth and rhenium (up to 2% atomic units) is N=69 units with an experimentally determined effective density value of ρ=8.3-8.5 g/cm 3 .
[0133] X-Ray Luminescent Material Processing.
[0134] If a material comprises more than 10 elements, then a technology for the production of this material must be proposed eliminating the possibility of inhomogeneity of the product in terms of the elements' concentration, while providing for a scheduled synthesis of the compound subject to any requirements of the chemical strength and stability.
[0135] It should be noted that the luminescent materials in a similarly claimed invention proposes processing either mainly by vacuum evaporation of the column whisker crystals of CsJ:Tl type or by chemical one-stage molt processing of gadolinium oxysulfide Gd 2 O 2 S:Tb.
[0136] As the closest counterpart, we suggest molt processing of the proposed X-ray luminescent material composed of rear-earth ions and d-shell ions (Bi, Re, Br −1 and J −1 ), in a two-stage process synthesis. The first stage generates oxyhalides of the cationic group elements by means of interacting initially codeposited oxides of rear-earth elements, Bi and Re with ammonium halides under the temperature of T=400° C. to T=700° C. for 1-4 hours with subsequent secondary heat treatment in the alkali chalcogenides with a molecular ratio of 1:1 or 1:3 under the temperature of T=800° C. to T=1200° C. for 0.2 to 8 hours, with subsequent leaching of the final product with water and mineral acids solutions.
[0137] Thus, the main feature of the proposed generation of rear-earth X-ray luminescent material is of a chronological and temperature multi-stage nature along with use of various chemical reagents at each stage of the integrated process.
[0138] Several possible compositions of the X-ray luminescent material proposed in the patent claim are shown in the Table 4.
[0000]
TABLE 4
After-
Radiation
Energy
glow
Cationic Sublattice
Anionic
Λ max,
Efficiency,
Period,
Composition
Sublattice
Nm
%
Ms
d 50
Gd 0.4 Lu 0.5 Eu 0.1
O, S
626,707
20
3
8-9
Gd 0.3 Lu 0.55 Bi 0.05 Eu 0.1
O, Br, S
626,708
21.5
2.6
6-10
Gd 0.3 Lu 0.55 Re 0.05 Eu 0.08 Sm 0.2
O, J, S
626,708
22
3.2
8-12
Gd 0.5 Lu 0.35 Bi 0.05 Eu 0.09 Sm 0.01
O, J, S, Se, Br
628,710
24.8
3.4
8-12
Gd 2 O 2 S: Tb
S
545
14-18
3
6
[0139] Another feature of the proposed synthesis process is the development of textured grains of rear-earth X-ray luminescent material. One of such grains is shown in the FIG. 4 , which implies high uniformity of generated grains along with their high optical transparency and uniaxiality.
[0140] To enhance the exterior resistance of the X-ray luminescent material grains, their surface is covered with a thin translucent coating based on zinc silicate. ZnO.SiO 2 , 40 nm to 100 nm thick. This coating is solid and provides grain protection from H 2 O and active gases. Furthermore, this zinc silicate film provides good flowability and prevents agglomeration of the luminescent material grains.
[0141] We tried a special technique to determinate the possible inclusion of agglomerated grains in the bulk product. The technique involves a volumetric measurement of a particular mass of luminescent material grains. To enhance repeatability, the batch weight of the luminescent material is vibrated in a calibrated cylinder under 5 Hz frequency for 5 minutes. The resulting volume of the X-ray luminescent material powder is a function of the chemical composition, the grain shape and the presence of agglomerates. In accordance with the proposed technique, the specific volume value for the X-ray luminescent material (Gd 0.3 Lu 0.55 Bi 0.05 Eu 0.01 ) 1.9 O 1.9 (B,J) 0.1 (S,Se) 1 amounted to ρ=4.8-4.9 g/cm 3 . This appears to be a very significant value taking into consideration the estimated theoretical density of the luminescent substance about Σ=8.3-8.5 g/cm 3 . This advantage of high bulk density is realized in the proposed detector which features a very high filling density of hetero-phase layers, approximately 40 to 120 mg/cm 2 .
[0142] Thus, the resulting high values of bulk density of the X-ray luminescent material allows for enhancement of the integral light intensity value for the multi-element X-ray imaging detector. Our measurements of the integral light intensity value for the X-ray beam energy 80 keV exceeded 4 cd/m 2 .
[0143] Photodiode Matrix.
[0144] The next design element of the novel device are photodiodes, arranged in a matrix with n-lines and m-rows. The values “n” and “m” depend on the size of the examined object. Thus, as we have seen in previous research, n=64 and m=64 are well enough for dentofacial X-ray examination. The matrix of 256*256 elements fully meets the requirements for dentofacial application. The matrix of 256*256 to 512*512 elements are suitable for mammalogy, and 1.024*1024 are sufficient for larger objects. Such matrices are suitable for most X-ray examination of child, patients 10 years old and younger. The largest matrices of 3072*3072 (square) and 2048*4096 (oblong) elements are required in adult patient examinations. These wide-screen matrices provides for a 440*440 mm field of view, which is more than any field provided in the X-ray EOICs (200*200 mm).
[0145] In reviewing the invention, we mentioned that photosensitive elements may be manufactured as a matrix utilizing various chemical elements. The first constructions of digital matrix X-ray detectors used matrices with elementary selenium Se. This material is easily vacuum evaporated (T evp ≈600° C.), allowing for the processing of different structures by means of a template deposit evaporation of up to 2000 elements on a single side, preserving high precision. But despite the proven technology, selenium matrices had apparent deficiencies—the integral photosensitivity value was about ones lux per 1 cm 2 which required a lot of light emission by the X-ray luminescent material. The low sensitivity of the selenium layer in turn required a high working current in the X-ray tubes (radiation sources), resulting in significant radiation exposure to patients.
[0146] An important step forward was made when multi-elemental detectors began to utilize elementary silicon. Initially, while the design implied an optical transfer of image, CCD-matrices were required which featured sensitivity of up to 10 −4 lux per element. Yet, these high values of sensitivity were attainable in monocrystalline silicon elements, making construction economically unsound and technically inappropriate if a large detector was needed.
[0147] The development of active matrix liquid crystal displays provided for polycrystalline and even noncrystalline film silicone coatings. Processing and properties of the coatings were different, and these issues are particularly discussed below.
[0148] First, we describe the technology of manufacturing the proposed silicon matrix detector using materials of Scint-x (Scintillator technology) company. The process flow comprises six stages:
[0149] Stage one—surface oxidation of the primary polycrystalline coating. Oxidation is performed in an oxygen atmosphere and required initiation by gas-discharge oxygen plasma under pressure p=10 mm Hg. SiO 2 film generated on the polycrystalline silicone surface is δ=250 nm to δ=1.5 μm.
[0150] Stage two—photolithography over polycrystalline silicon. The primary layer of the photoresist is applied over silicon by a centrifuge process. The photoresist obtains photosensitivity during polymerization due to special ingredients.
[0151] Applied heating of the photoresist layer makes it thinner. Then, the photoresist layer is exposed to hard ultra-violet and blue radiation through a chromed negative. The areas of the photoresist layer exposed to UV-light are polymerized with the formation of an insoluble coating. The rest of the photoresist is removed from the polycrystalline silicon substrate which bears polymerized areas of photoresist.
[0152] The next stage is the opening of the silicon dioxide layer. Usually, this process takes place in an HF atmosphere of under-fluorinated hydrogen halide plasma in special apparatuses.
[0153] Gaseous SiF 4 generated during the etching of the silicon dioxide is removed, and are opened in the silicon dioxide channels, providing for further direct etching of the silicon.
[0154] The next stage is silicon layer etching. It is done either by electrochemical etching or by a deep reactive ion etching (DRIE) method. The surface lattice of the silicon dioxide prevents direct etching of the polycrystalline silicone layer. Thus, the etched channels and the relief areas of the polycrystalline silicone form the required texture of the scintillator detector's photodetectors.
[0155] According to Scint-x Company, the next stage is the coating of the formed multi-element silicon matrix with a film of scintillating substance. One of variants of our invention suggests covering the detector matrix directly with a metal grid sheet, fix it over the photodetector matrix, and then cast the multi-element scintillating layer in place. For this technique, we selected the optimum polymer composition for a detector providing for X-ray resistance. The polymer we proposed stands while heating up to T=400° C. without destruction. Another important property of the polymer is its high resistance to different types of penetrating radiation, including X-ray.
[0156] The final stage, according to Scint-x Company, is the photosensitive matrix passivation by coating it with a transparent to scintillator radiation layer.
[0157] If the image resolution is of prime importance for the device along with a high contrast, then the workflow must be strictly adhered to: initially, the silicon matrix substrate must be produced for optical signal reading, and then, the multi-element layer of the radiation detector must be formed over this substrate. For proper aligning of the silicon photodetectors' centers with the centers of the scintillating X-ray-sensitive detector, a diagonal three-point aligning system is used which implies the positioning of three protruding reference marks on the silicon matrix, which centers are used to position the grid plate of the scintillating detector. The external surface of the grid sheet is coated with a thin translucent film which allows for the fixation and alignment of the photodiode matrix sheet and the matrix scintillating detector sheet. Furthermore, the arranged set is placed onto the cast machine's moving plate, which casts polycarbonate X-ray luminescent material suspension into the grid cells. Thus, the detector obtains the required characteristics of high X-ray sensitivity and image brightness.
[0158] The differences are realized in a multi-element detector, which X-ray sensitive layer is formed directly on the silicon photosensitive cells with the grid sheet fixed above so that the optical centers of the photosensitive cells are aligned with the centers of the “live cross-section” of each of the grid cells.
[0159] As we have discovered, in high-energy systems, the scintillator (full-depth hetero-phase X-ray luminescent layer detector) is more practical for casting in two or three stages with an intermediate polymerization of each of the casted hetero-phase layer. The suggested polymerization temperature of T=130-140° C. does not affect the consistency of the silicon photodetector matrix. The mass load of a single layer by the X-ray luminescent material is m=20-25 mg/cm 2 which is equivalent to the complete absorption of X-ray radiation with an initial energy of E=40 keV. The second cast hetero-phase scintillating layer with a mass load of m=20-25 mg/cm 2 results in coating capable of absorbing radiation with an initial energy of E=80 keV. In the third cast layer, the coating thickness is enough for absorption of E=120 keV, which is suitable for major medical and diagnostic applications.
[0160] Thus resulting multi-layer silicon and polymer scintillating structure is prepared for testing. This requires cleaning the commutation wiring of the photodiode matrix and collecting them into terminals of many contact wires. The terminals are fixed in the peripheral receptacles.
[0161] Initial testing of the device is performed in a Siemens or similar X-ray apparatus under testing radiation energy of E=80 keV. A round template with cells of different sizes is used as a reference.
[0162] FIG. 5 shows a photo of the multi-element detector display with a center circle diameter of 120 mm. As it appears from the photo, the resolution power of the construction is far above 4 pairs of lines per 1 millimeter.
[0163] The full contrast range is above 50% while improvement of the luminescent material composition, luminescent material thickness, and characteristics of the woven grid sheet results in a virtually complete balancing and reduction of background glowing. This advantage is realized in the proposed multi-element detector featuring imaging contrast in excess of 50% along with resolution power above 4 pairs of lines per 1 millimeter. We have not seen a similar description of imaging quality without ghost glowing in the cited literature.
[0164] The development and industrial processing of the proposed detector is a complex, advanced production process which requires high-quality workflow implementation. A production launch of the detectors is planned for 2010.
CITED LITERATURE
[0000]
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18. Metallic grids. GOST 6613-86, 2002. | The invention relates to X-ray technology and medical diagnostics, and can be used for carrying out gamma flaw detection on various articles and piping systems. The technical result is an increase in contrast of the integrated image that is produced. A multi-element X-ray radiation detector consists of a flat multi-element scintillator in the form of a discrete set of hetero-phase luminescent elements which are arranged in the cells of a mesh made from a metal which absorbs X-ray radiation and reflects light, the increment size of which mesh corresponds to the increment size of the photo receiver matrix. The metallic mesh that forms the multi-element luminescent scintillator is made from elements having an atomic number from N=26 (iron) to N=74 (tungsten), has silver-plated coils, and separates the scintillator elements optically from one another. The coils of the mesh have a diameter from 0.06 mm to 0.16 mm, and the area of the effective cross section of the mesh is between 45% to 82%. The scintillator consists of an X-ray luminophore based on a multi-ligand oxysulphide of gadolinium-lutetium-europium with the addition of bismuth and rhenium, and also fluorine, chlorine, bromine and iodine. The process of synthesis is carried out in two stages. In the first stage, oxyhalides of the elements making up a cationic subgroup are formed by reacting the initial coprecipitated oxides of rare earth elements, Bi and Re, with ammonium halides. The resulting product is then subjected to repeated thermal treatment in an alkali chalcogenide melt. | 2 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is based upon and claims the benefit of priority of Japanese Patent Application No. 2004-164857, filed on Jun. 2, 2004, the entire contents of which are herein incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention generally relates to a semiconductor device, and more particularly relates to a semiconductor device which has the power supply wiring to supply power to a circuit part of a semiconductor chip via a power-supply line of the semiconductor chip.
[0004] 2. Description of the Related Art
[0005] Conventionally, in the semiconductor device in which the semiconductor chip is mounted using the wire bonding method, the electrode at the peripheral part of the semiconductor chip carried on the substrate and the bonding lead on the substrate are electrically connected together by a wire etc.
[0006] At the time of operation, the power supply current is supplied from the electrode of the peripheral part of the semiconductor chip to the circuit part in the center of the semiconductor chip through the power-supply line.
[0007] FIG. 1 shows the composition of the conventional semiconductor device 10 . The semiconductor chip 1 , such as LSI, is carried on the interposer used as the substrate indicated by the dotted line in FIG. 1 . The semiconductor chip 1 comprises the core part 5 which forms the circuit part, the plurality of electrode pads 2 disposed at the peripheral part of the core part 5 , and the power-supply line 4 .
[0008] The electrode pad 2 disposed for the power supply, among the plurality of electrode pads 2 , is connected by the circuit part and the power-supply line 4 of the semiconductor chip 1 . The electrode pad 2 disposed for the grounding, among the plurality of electrode pads 2 , is connected by the circuit part and the power-supply line 4 of the semiconductor chip 1 .
[0009] The power supply current from the power supply (not illustrated) is supplied at the time of operation to the circuit of the core part 5 in the center of the semiconductor chip 1 through the power-supply line 4 from the periphery of the semiconductor chip 1 .
[0010] On the substrate of the semiconductor device 1 , the plurality of bonding leads 7 are disposed in the region encircling the semiconductor chip 1 . Among the plurality of bonding leads 7 , the bonding lead 7 for the power supply is connected to the power supply (not illustrated), and the bonding lead 7 for the grounding among the plurality of bonding leads 7 is grounded. All the bonding leads 7 provided on the substrate are electrically bonded to the electrode pads 2 at the periphery of the semiconductor chip 1 by the wires 8 .
[0011] As the known method concerning the power supply wiring of the semiconductor device, Japanese Laid-Open Patent Application No. 03-008360 discloses the power supply wiring provided in the semiconductor device having the plurality of wiring layers. This semiconductor device has the wiring structure in which the plurality of semiconductor chips and the power supply wiring are connected via the through holes.
[0012] Moreover, Japanese Laid-Open Patent Application No. 64-089447 discloses the semiconductor integrated circuit device having the multilayer interconnection structure. In order to avoid the influence from the electric field and the magnetic field on the exterior of the integrated circuit, the semiconductor circuit device is configured to have the wiring structure in which at least one conductor layer among the plurality of conductor layers is connected to the power supply or the ground so as to cover entirely the periphery of the element (transistor) on the substrate.
[0013] In the conventional semiconductor device 10 of FIG. 1 , the power supply current is supplied to the core part 5 of the semiconductor chip 1 via the power-supply line 4 at the time of operation. However, there is a tendency that the supply voltage in the center of the core part 5 falls to be lower than the supply voltage at the peripheral part of the core part 5 .
[0014] Especially, at the time of high-speed operation, the power supply current is consumed with the passive component parts, such as resistors and inductors, and the supply voltage in the center of the core part 5 will be lower than the supply voltage in the peripheral part of the core part 5 . There may arise the problem in which the predetermined operation cannot be performed by the circuit part of the semiconductor chip 1 due to the supply voltage drop. Therefore, in the case of the conventional semiconductor device 10 , the supply voltage drop becomes the cause of the operational fault of the semiconductor chip 1 .
SUMMARY OF THE INVENTION
[0015] An object of the present invention is to provide an improved semiconductor device in which the above-mentioned problems are eliminated.
[0016] Another object of the present invention is to provide a simple and low-cost semiconductor device in which the structure of the power-supply line is improved and the operation of the semiconductor chip can be stabilized effectively.
[0017] In order to achieve the above-mentioned objects, the present invention provides a semiconductor device in which the openings are respectively formed on the power-supply line in the center of the circuit part of the semiconductor chip and the power-supply line at the peripheral part of the circuit part of the semiconductor chip. And the power-supply line on the opening of the center of the circuit part and the power-supply line on the opening of the peripheral part of the circuit part are mutually connected by the conductor layer formed from the silver paste etc. It is possible to make the power supply current supplied in the center of the circuit part during the operation increase. Therefore, it is possible for the present invention to prevent that the supply voltage in the center of the circuit part falls during the operation, and the operation of the semiconductor chip can be stabilized effectively.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] Other objects, features and advantages of the present invention will be apparent from the following detailed description when read in conjunction with the accompanying drawings.
[0019] FIG. 1 is a diagram showing the composition of the conventional semiconductor device.
[0020] FIG. 2A is a diagram for explaining the conductor layer formed on the power-supply line of the circuit part of the semiconductor chip in the preferred embodiment of the present invention.
[0021] FIG. 2B is a diagram for explaining the conductor layer formed on the power-supply line of the circuit part of the semiconductor chip in the preferred embodiment of the present invention.
[0022] FIG. 3 is a cross-sectional view showing the connection between the power-supply line and the conductor layer in the semiconductor chip of FIG. 2B .
[0023] FIG. 4 is a diagram showing the composition of the semiconductor device in one embodiment of the present invention.
[0024] FIG. 5 is a diagram showing the composition of the semiconductor device in another embodiment of the present invention.
[0025] FIG. 6 is a cross-sectional view showing the connection between the substrate, the semiconductor chip and the conductor layer in the semiconductor device of FIG. 5 .
[0026] FIG. 7 is a diagram showing the composition of the semiconductor device in another embodiment of the present invention.
[0027] FIG. 8 is a cross-sectional view showing the connection between the TAB tape, the semiconductor chip and the conductor layer in the semiconductor device of FIG. 7 .
[0028] FIG. 9 is a cross-sectional view showing the cross-sectional structure of the semiconductor chip of FIG. 2B .
[0029] FIG. 10 is a side view showing the connection between the wiring board, the semiconductor chip and the conductor layer in the semiconductor device of FIG. 4 .
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0030] A description will now be given of the preferred embodiments of the present invention with reference to the accompanying drawings.
[0031] FIG. 4 shows the composition of the semiconductor device in one preferred embodiment of the present invention. FIG. 10 shows the connection between the wiring board, the semiconductor chip and the conductor layer in the semiconductor device of FIG. 4 .
[0032] The semiconductor device 20 of FIG. 4 comprises the semiconductor chip 11 carried on the wiring board 21 , such as LSI. The wiring board 21 is used as the interposer, for example. The semiconductor chip 11 contains the circuit part (core part) formed in the center, the plurality of electrode pads 12 disposed at the peripheral part of the circuit part, and the power-supply line 14 .
[0033] As shown in FIG. 10 , the semiconductor chip 11 is mounted on the wiring board 21 via the die material 21 a with its circuit part formed on the front surface being placed up side and its back surface being placed down side. The electrode pad 12 disposed for the power supply among the plurality of electrode pads 12 is connected with the circuit part and the power-supply line 14 of the semiconductor chip 11 .
[0034] The electrode pad 12 disposed for the grounding among the plurality of electrode pads 12 is connected with the circuit part and the power-supply line 14 of the semiconductor chip 11 . The power supply current from the power supply (not illustrated) is supplied at the time of operation from the peripheral part of the semiconductor chip 11 to the circuit part in the center of the semiconductor chip through the power-supply line 14 .
[0035] On the wiring board 21 of the semiconductor device 20 , the plurality of bonding leads 17 are disposed in the region encircling the semiconductor chip 11 . Among the plurality of bonding leads 17 , the bonding lead 17 for the power supply is connected with the power supply (not illustrated), and the bonding lead 17 for the grounding among the plurality of bonding leads 17 is grounded.
[0036] Each electrode pad 12 at the periphery of the semiconductor chip 11 is electrically connected to one of the plurality of bonding leads 17 by a wire 18 , respectively.
[0037] In order to solve the problem in which the supply voltage supplied in the center of the circuit part of the semiconductor chip falls at the time of operation of the conventional semiconductor device mentioned above, the semiconductor device 20 of FIG. 4 is configured as in the following. The opening 13 is formed on each of the power-supply lines 14 in the center and at the peripheral part of the circuit part of the semiconductor chip 11 , respectively. The conductor layer 16 is formed on these openings 13 to cover the whole surface of the circuit part of the semiconductor chip 11 , and the power-supply line 14 on the opening 13 of the center of the circuit part and the power-supply line 14 on the opening 13 of the peripheral part of the circuit part are mutually connected by the conductor layer 16 .
[0038] This conductor layer 16 can be formed by applying the conductive material, such as a silver paste, to the semiconductor chip 11 . The bonding leads 17 for the conductor layer, among the plurality of bonding leads 17 on the wiring board 21 of the semiconductor device 20 , are electrically connected to the conductor layer 16 by the wires 18 . These bonding leads 17 for the conductor layer (in the example of FIG. 4 , eight pieces) include the bonding lead connected to the power supply (not illustrated), and the bonding lead connected to the ground.
[0039] Therefore, at the time of operation, the power supply current from the power supply (not illustrated) is directly supplied to the conductor layer 16 through the bonding leads 17 for the conductor layer and the wires 18 . By forming this conductor layer 16 in the semiconductor device of the present invention, it is possible to increase the amount of the power supply current supplied to the circuit part in the center of the semiconductor chip 11 at the time of operation.
[0040] Therefore, in the time of operation, it is possible to prevent the falling of the supply voltage in the center of the circuit part of the semiconductor chip 11 , and the operation of the semiconductor ship 11 can be stabilized effectively.
[0041] FIG. 2A and FIG. 2B are diagrams for explaining the conductor layer 16 formed on the power-supply line 14 of the circuit part of the semiconductor chip 11 of FIG. 4 .
[0042] Before forming the conductor layer 16 , the plurality of openings 13 are formed on the power-supply line 14 of the semiconductor chip 11 as shown in FIG. 2A . The positions where the plurality of openings 13 are formed are distributed equally for the positions on the power-supply line 14 near the peripheral part of the circuit part of the semiconductor chip 11 , and the positions on the power-supply line 14 near the center of the circuit part of the semiconductor chip 11 in which the voltage drop tends to arise.
[0043] In each of the plurality of openings 13 , the opening is formed such that other wiring layers, insulating layers, etc. may not close a part of the power-supply line 14 of the semiconductor chip 11 . These openings 13 can be formed additionally within the manufacturing processes of the semiconductor chip 11 . Alternatively, these openings 13 may be formed after the manufacture of the semiconductor chip 11 .
[0044] As shown in FIG. 2B , after the plurality of openings 13 are formed, the conductor layer 16 is formed thereon. By applying or printing the conductive substance, such as a silver paste, the conductor layer 16 is formed to cover all the plurality of openings 13 on the semiconductor chip 11 , and the conductor layer 16 and the power-supply line 14 are connected together at each opening 13 .
[0045] FIG. 9 shows the cross-sectional structure of the semiconductor chip 11 of FIG. 2B .
[0046] As shown in FIG. 9 , the semiconductor chip 11 comprises the substrate 19 , such as silicon, the wiring layer 15 formed on the substrate 19 , the conductor layer 16 formed on the wiring layer 15 , and the electrode pads 12 . The wiring layer 15 includes the insulating layer 15 a , the power-supply line 14 , and other wiring layers.
[0047] The opening 13 is formed by removing the insulating layer 15 a of the wiring layer 15 , so that the power-supply line 14 is exposed. The conductor layer 16 is formed by applying or printing the silver paste or the like, so that all the openings 13 on the semiconductor chip 11 are covered by the conductor layer 16 .
[0048] In this embodiment, the silver (Ag) content of the silver paste used is 60% or more, the silver paste is heated and hardened, and the silver content of the hardened material is 99% or more. It is a matter of course that the metal, such as gold (Au) or copper (Cu), and other conductive substances, other than silver (Ag), may be used as the material for forming the conductor layer 16 .
[0049] FIG. 3 shows the connection between the power-supply line 14 and the conductor layer 16 in the opening 13 of the semiconductor chip 11 of FIG. 2B .
[0050] The wiring of the semiconductor chip 11 of FIG. 2B is formed with aluminum (Al) or copper (Cu) and the wiring width of the power-supply line 14 is comparatively small (about ten micrometers). For this reason, before the silver paste is applied, the non-electrolytic plating is performed so that the plating of nickel (Ni) and gold (Au) is formed on the power-supply line 14 at the position of the opening 13 , in order to avoid the disconnection of the wiring by the thermal stress at the time of hardening of the silver paste.
[0051] As shown in FIG. 3 , in the opening 13 disposed in the circuit part of the semiconductor chip 11 , the nickel plating layer 17 a and the Au plating layer 17 b are formed on the power-supply line 14 , and the conductor layer 16 is further formed on the plating layers 17 a and 17 b by applying and hardening of the silver paste, so that the conductive layer 16 covers almost the whole surface of the circuit part of the semiconductor chip 11 including the center and the peripheral part thereof.
[0052] In the semiconductor device 20 having the above-described structure, the opening 13 disposed in the center of the circuit part of the semiconductor chip 11 and the openings 13 disposed at the peripheral part of the circuit part of the semiconductor chip 11 are connected with each other by the conductor layer 16 , and the conductor layer 16 is electrically connected with the power-supply line 14 at each of these openings 13 .
[0053] As explained above, in the semiconductor device 20 of FIG. 4 , by forming the openings 13 and the conductor layer 16 in the circuit part of the semiconductor chip 11 , it is possible to increase the power supply current supplied to the circuit part in the center of the semiconductor chip 11 at the time of operation. Therefore, it is possible to prevent the falling of the supply voltage in the center of the circuit part of the semiconductor chip 11 at the time of operation, and the operation of the semiconductor chip 11 can be stabilized effectively.
[0054] In addition, the openings 13 and the conductor layer 16 in this embodiment can be easily formed on the semiconductor chip 11 by using the known wiring method, and it is possible for the present invention to provide a simple and low-cost semiconductor device.
[0055] Next, the semiconductor device in another embodiment of the present invention will be explained using FIG. 5 and FIG. 6 .
[0056] As for the chip mounting technology which mounts the IC or LSI chip, the wire bonding method, the flip-chip bonding method, the TAB (Tape Automated Bonding) method, etc. are known. And these methods are properly used depending on the device or product field concerned.
[0057] The above-described semiconductor device 20 of FIG. 4 is one embodiment of the invention in which the mounting of the semiconductor chip is performed by using the wire bonding method.
[0058] In contrast, the semiconductor device 30 shown in FIG. 5 and FIG. 6 is one embodiment of the invention in which the mounting of the semiconductor chip is performed by using the flip-chip bonding method.
[0059] FIG. 5 shows the composition of the circuit formation surface (back surface) of the semiconductor chip 11 a in this embodiment. FIG. 6 shows the connection between the substrate 22 , the semiconductor chip 11 a , and the conductor layer 16 in the semiconductor device 30 of this embodiment.
[0060] The semiconductor device 30 of this embodiment comprises the semiconductor chip 11 a carried on the substrate 22 , such as LSI. Unlike the semiconductor chip 11 of FIG. 2B in which the plurality of electrode pads 12 are disposed, the plurality of bumps 12 a are disposed at the peripheral part of the semiconductor chip 11 a in this embodiment, instead of the plurality of electrode pads 12 , as shown in FIG. 5 .
[0061] As shown in FIG. 5 , the semiconductor chip 11 a comprises the circuit part (core part) formed in the center, the plurality of bumps 12 a disposed at the peripheral part of the circuit part, the power-supply line 14 , the plurality of openings 13 , and the conductor layer 16 . The bump 12 a disposed for the power supply, among the plurality of bumps 12 a , is connected with the circuit part and the power-supply line 14 of the semiconductor chip 11 a . The bump 12 a disposed for the grounding, among the plurality of bumps 12 a , is connected with the circuit part and the power-supply line 14 of the semiconductor chip 11 a.
[0062] The power supply current from the power supply (not illustrated) is supplied at the time of operation from the peripheral part of the semiconductor chip 11 a to the circuit part in the center of the semiconductor chip 11 a through the power-supply line 14 .
[0063] The openings 13 are formed respectively on the power-supply line 14 disposed in the center of the circuit part of the semiconductor chip 11 a and on the power-supply line 14 at the peripheral part of the circuit part of the semiconductor chip 11 a . The conductor layer 16 is formed on these openings 13 to cover the whole surface of the circuit part of the semiconductor chip 11 a , and the power-supply line 14 on the opening 13 of the center of the circuit part and the power-supply line 14 on the opening 13 of the peripheral part of the circuit part are connected with each other by the conductor layer 16 .
[0064] Similar to the formation method mentioned above using FIG. 2B , the conductor layer 16 can be formed by applying and hardening the conductive material, such as a silver paste, to the semiconductor chip 11 a . In the following, the overlapping explanation will be omitted.
[0065] As shown in FIG. 6 , the terminal 24 is disposed on the substrate 22 of the semiconductor device 30 in the region confronting the circuit part of the semiconductor chip 11 a , and the plurality of terminals 23 are disposed on the substrate 22 in the region confronting the plurality of bumps 12 a of the semiconductor chip 11 a.
[0066] Among the plurality of terminals 23 , the terminal 23 for the power supply is connected with the power supply (not illustrated), and the terminal 23 for the grounding among the plurality of terminals 23 is grounded.
[0067] In the semiconductor device 30 of FIG. 6 , each of the plurality of bumps 12 a at the periphery of the semiconductor chip 11 a is electrically connected to one of the plurality of terminals 23 disposed on the substrate 22 , respectively. The conductor layer 16 in the center of the semiconductor chip 11 a is also electrically connected to the terminal 24 disposed on the substrate 22 .
[0068] Similar to the previous embodiment of FIG. 4 , in the semiconductor device 30 of this embodiment, by forming the openings 13 and the conductor layer 16 in the circuit part of the semiconductor chip 11 a , it is possible to increase the power supply current supplied to the circuit part in the center of the semiconductor chip 11 a at the time of operation. Therefore, it is possible to prevent the falling of the supply voltage in the center of the circuit part of the semiconductor chip 11 a at the time of operation, and the operation of the semiconductor chip 11 a can be stabilized effectively.
[0069] Since the openings 13 and the conductor layer 16 in this embodiment can also be easily formed on the semiconductor chip 11 a by using the known wiring method, it is possible for the present invention to provide a simple and low-cost semiconductor device.
[0070] Next, the semiconductor device in another embodiment of the present invention will be explained using FIG. 7 and FIG. 8 .
[0071] As mentioned above, the semiconductor device 20 of FIG. 4 is one embodiment of the invention in which the mounting of the semiconductor chip is performed by using the wire bonding method. In contrast, the semiconductor device 40 shown in FIG. 7 and FIG. 8 is one embodiment of the invention in which the mounting of the semiconductor chip is performed by using the TAB method.
[0072] FIG. 7 shows the composition of the circuit formation surface (front surface) of the semiconductor chip 11 b of this embodiment and the TAB tape 28 . FIG. 8 shows the connection between the TAB tape 28 , the semiconductor chip 11 b and the conductor layer 16 in the semiconductor device 40 of this embodiment.
[0073] The semiconductor device 40 of this embodiment comprises the semiconductor chip 11 b carried on the TAB tape 28 . Unlike the example of FIG. 2B , the plurality of bumps 12 b are disposed at the peripheral part of the semiconductor chip 11 b as shown in FIG. 7 , instead of the plurality of electrode pads 12 .
[0074] As shown in FIG. 7 , the semiconductor chip 11 b comprises the circuit part (core part) formed in the center, the plurality of bumps 12 b disposed at the peripheral part of the circuit part, the power-supply line 14 , the plurality of openings 13 , and the conductor layer 16 .
[0075] The bump 12 b disposed for the power supply, among the plurality of bumps 12 b , is connected with the circuit part and the power-supply line 14 of the semiconductor chip 11 b . The bump 12 b disposed for the grounding, among the plurality of bumps 12 b , is connected with the circuit part and the power-supply line 14 of the semiconductor chip 11 b.
[0076] The power supply current from the power supply (not illustrated) is supplied, at the time of operation, from the peripheral part of the semiconductor chip 11 b to the central circuit part through the power-supply line 14 .
[0077] The openings 13 are formed respectively on the power-supply line 14 disposed in the center of the circuit part of the semiconductor chip 11 a and on the power-supply line disposed at the peripheral part of the circuit part of the semiconductor chip 11 b . The conductor layer 16 is formed on these openings 13 to cover the whole surface of the circuit part of the semiconductor chip 11 b , and the power-supply line 14 on the opening 13 of the center of the circuit part and the power-supply line 14 on the opening 13 of the peripheral part of the circuit part are connected with each other by the conductor layer 16 .
[0078] Similar to the formation method mentioned above using FIG. 2B , the conductor layer 16 can be formed by applying and hardening the conductive material, such as a silver paste, to the semiconductor chip 11 b . In the following, the overlapping explanation will be omitted.
[0079] In the TAB tape 28 , the plurality of leads 27 are disposed at the positions confronting the plurality of bumps 12 b of the semiconductor chip 11 b respectively. The lead 27 for the power supply, among the plurality of leads 27 , is connected with the power supply (not illustrated), and the lead 27 for the grounding among the plurality of leads 27 is grounded. Furthermore, a pair of leads 29 for the power supply which are arranged in the X-shaped formation are disposed in the opening of the TAB tape 28 at the position confronting the circuit part of the semiconductor chip 11 b.
[0080] As shown in FIG. 8 , in semiconductor device 40 of this embodiment, each of the plurality of bumps 12 b at the periphery of the semiconductor chip 11 b is electrically connected to one of the plurality of leads 27 disposed on the TAB tape 28 , respectively. And the conductor layer 16 in the center of the semiconductor chip 11 b is also electrically connected to the lead 29 for the power supply formed on the TAB tape 28 .
[0081] Similar to the previous embodiment of FIG. 4 , in the semiconductor device 40 of this embodiment, by forming the openings 13 and the conductor layer 16 in the circuit part of the semiconductor chip 11 b , it is possible to increase the power supply current supplied to the center of the circuit part of the semiconductor chip 11 b at the time of operation. Therefore, it is possible to prevent the falling of the supply voltage in the center of the circuit part of the semiconductor chip 11 b during the operation, and the operation of the semiconductor chip 11 b can be stabilized effectively. Since the openings 13 and the conductor layer 16 in this embodiment can also be easily formed on the semiconductor chip 11 b by using the known wiring method, it is possible for the present invention to provide a simple and low-cost semiconductor device.
[0082] The present invention is not limited to the above-described embodiments, and variations and modifications may be made without departing from the scope of the present invention. | A semiconductor device comprises a semiconductor chip in which a circuit part provided in a center of the semiconductor chip is connected with power-supply lines and power-supply electrodes to supply power from an external power source to the circuit part. A substrate is provided for carrying the semiconductor chip thereon and provided so that first terminals in a region encircling the semiconductor chip are electrically connected to the power-supply electrodes. A first opening is formed on the power-supply line in a center of the circuit part. A second opening is formed on the power-supply line at a peripheral part of the circuit part. A conductor layer is electrically connected to second terminals in the region encircling the semiconductor chip on the substrate, and provided so that the power-supply line in the first opening and the power-supply line in the second opening are connected together. | 7 |
FIELD OF THE INVENTION
[0001] The present invention relates to drilling subsea wells, and typically from a floating drilling rig. More particularly, this invention relates to a subsea riser disconnect equipment and techniques for sealingly connecting a lower riser extending downward into and fixed within a subsea well bore with an upper riser extending downward from the floating drilling rig, such that the upper riser may be disconnected from the fixed lower riser during adverse weather or other rig move-off conditions.
BACKGROUND OF THE INVENTION
[0002] Subsea wells are increasingly important to hydrocarbon recovery operations. Numerous land-based wells have been drilled, but the percentage of hydrocarbons recovered from land-based wells is steadily decreasing in some parts of the world. Jack-up rigs have been used offshore for decades to drill wells subsea to recover oil, but jack-up rigs are practically limited to drilling operations in relative shallow water of several hundred feet. As water depth increases other drilling rig options may be required to facilitate drilling and well completion operations. In addition to an increase in the number of off-shore wells being drilled, in more recent years an increasing number of wells are being drilled in deeper water and at increasing costs. Accordingly, drilling from offshore rigs, e.g., drilling ships, semi-submersibles, jack-ups, drilling barges or submersible rigs has significantly increased in recent years. The economics associated with drilling offshore remains, however, a primary reason why more wells are not drilled offshore. Particularly, in drilling exploratory wells where financial risk and commercial hydrocarbon uncertainty may severely impact the economics for drilling such wells, costs and may be more critical in determining whether any wells are drilled at all, and how many may be drilled.
[0003] The majority of offshore or marine drilling rigs utilize riser sections as the outermost tubular between the rig and the seafloor, with the riser sections typically being bolted, clamped, mechanically fixed by dog-type latch mechanisms or otherwise connected. Riser sections conventionally include hydraulic lines spaced outwardly of the assembled riser pipe for operating the blow out preventer (BOP) and subsea ram stack located above the mud line. During an emergency or in anticipation of adverse weather conditions, the subsea BOP may be closed and the rams hydraulically activated to seal off the well bore. Prior to closing the rams, the drill pipe may be threadably disconnected above or below the BOP stack utilizing a back off tool or back off method, or the drill pipe may be sheared by the shear ram assembly. In some applications, acoustically or electrically activated subsea accumulators have been used to replace the hydraulic lines which commonly are run along side the riser pipe. The subsea BOP stack assembly used during deep water drilling operations may contribute significantly to the cost of drilling a well and a substantial amount of expensive rig time may be expended running in and removing the riser pipe sections and related well control equipment.
[0004] The above disadvantages associated with drilling from floating drilling rigs have long been known. Accordingly, some drilling or operating companies may recommend “riser-less drilling” for certain deep water applications. A subsea pump may be provided to return the drilling fluid to the surface in a separate flow line. Riser-less drilling still has to contend with the high cost of the BOP stack and hydraulic operation of this equipment. Several wells have been successfully drilled from a floating drilling rig, while using a riser, wherein the BOP is placed on the drilling rig rather than subsea. To date, however, these wells practically are limited to geographic areas where and/or seasons when there is a reduced likelihood of adverse weather conditions which would require the floating drilling rig to relatively quickly disengage a portion of the riser, e.g., an upper riser from the lower riser. In these applications, however, elimination of the subsea BOP stack may result in significant cost savings when drilling a well. Further savings may be realized by using conventional threaded casing for a riser rather than flange-type riser pipe sections. Less area on the drilling vessel is required to store casing having the same nominal diameter as the riser pipe sections since conventional riser pipe sections include both flanges and hydraulic lines which are eliminated when using casing as the riser.
[0005] Typically, subsea BOP stacks are installed on the riser string. The BOP stack may be required to provide a subsea method of isolating a lower portion of the riser and well bore from the riser above the BOP stack. Stress in the riser typically includes the weight of the riser and the weight of the subsea BOP. Subsea BOP stacks may weigh in excess of 400,000 pounds. The weight of the BOP stack plus the weight of a riser sufficiently strong enough to deploy such stack and meet operational requirements necessitates that risers are inherently heavy pieces of equipment which may exert high levels of stress and strain on the drilling and on the riser sections. These effects may be even more pronounced in deep water applications. In deep water installations, installation of a typical riser system may require calm weather and well in excess of a week to install, and in excess of a week to retract. In addition to the subsea riser and BOP stack, electrical and hydraulic umbilical lines are typically deployed concurrently, to control and operate the BOP stack, choke and kill line valves, and hydraulic disconnects if present. Deployment and recovery of this equipment and the rig time involved all contribute significantly to well costs, as daily rental rates for semi-submersible drilling rigs may exceed $240,00 per day. Premature disconnection of a portion of the riser can likewise be expensive and time consuming, such as may be necessary in advance of hostile weather conditions, broken mooring chain or slipping mooring anchor.
[0006] If drill pipe is in a well bore and it becomes necessary to seal the interior of the well bore, pipe rams or shear rams in the BOP stack may be closed on the drill string to confine pressure and fluid within the well bore. In the event it becomes necessary to disconnect an upper portion of the drill pipe from a lower portion of the drill pipe, the drill pipe may be unthreaded at a tool joint, or cut with a chemical cutter or explosive charge. If pipe is stuck, the free point may be estimated by a free point calculation technique. Each of these disconnect methods requires time to determine free points, deploy appropriate tools on wire line, such as a “string shot,” a free-point tool, a chemical cutter or jet-shot explosive charge. Multiple attempts and re-calculations may be required. The process can be time consuming and frustrating and may still result disconnecting at an undesirable disconnect point. Reconnecting after disconnecting can be even more exasperating, time consuming and expensive, and even impossible.
[0007] Disadvantages of the prior art are overcome by the present invention. An improved method of drilling from a floating drilling rig is hereinafter disclosed. A subsea riser disconnect is provided for connecting and disconnecting a lower riser from an upper riser.
SUMMARY OF THE INVENTION
[0008] This invention provides means and equipment for relatively quickly, physically disconnecting a floating drilling rig from a subsea well in a manner that may be operationally and economically more efficient than prior art equipment and techniques. In the event hostile weather conditions, rig conditions or well conditions threaten the safety or operating capabilities of an offshore drilling rig or work over vessel, the rig or vessel may be disconnected and moved out of harms way. The rig may later return to the well location and reconnect to the disconnected members. This invention provides means and equipment for installing a riser system and well control system which may provide for a more cost effective offshore drilling and/or work over operations than is available under prior art. Such improvements may reduce the costs to find, develop and produce hydrocarbons.
[0009] In one embodiment, this invention generally includes three primary components: a) a maritime or subsea riser disconnect for disconnecting and reconnecting an upper portion of the riser with a lower portion of the riser, b) a subsea riser valve for sealing off an interior of a well bore below the riser valve, and c) a drill pipe disconnect for disconnecting and reconnecting an upper portion of the drill pipe with a lower portion of the drill pipe.
[0010] Subsea Riser Disconnect
[0011] A preferred embodiment of a subsea riser disconnect includes an apparatus and means which disconnects an upper portion of the subsea riser from a lower portion of the riser, through axial movement of the upper riser relative to the lower riser. The upper riser and the lower riser may be collectively referred to as a riser system. The subsea riser disconnect may be positioned at substantially any point within the riser system, e.g., between the drilling rig and the mud line. The subsea riser is preferably accessible to either a remotely operated vehicle (ROV) or a diver, in order that a riser disconnect lockout device may be operated if needed. The subsea riser disconnect may facilitate placing the blow out preventer and well control stack (BOP) either on the rig or suspended from but relatively near the rig.
[0012] A preferred embodiment of a riser disconnect may include a male disconnect member secured to the lower end of the upper riser, and a female disconnect member secured to the upper end of the lower riser. The male disconnect member may include a seal mandrel and seal elements for providing a hydraulic seal between the male disconnect member and female disconnect member. The male disconnect member may also include a collet mechanism to facilitate latching and unlatching the male and female disconnect members. A lockout device may be included to prevent inadvertent actuation of the subsea riser disconnect, such as during initial installation of the riser disconnect and riser system. Manipulation of the lockout may be externally performed, such as by ROV, diver or otherwise.
[0013] The female riser disconnect member may include a seal bore receptacle for sealingly receiving the seal mandrel within the seal bore receptacle, and a circumferential collet groove may be included in an inner surface of the female riser disconnect for engaging collet dogs. A conical shaped entry guide may be included on an upper end of the lower riser disconnect member to guide the male disconnect member into the female disconnect member during subsea connection of the male and female disconnect member.
[0014] Manipulation of the riser disconnect latch may be performed by axial motion or reciprocation of the upper riser relative to the lower riser. (The terms “axial reciprocation, reciprocation, axial motion, axial, or similar variations of these terms, as used herein may be defined to be substantially synonymous, and include linear displacement of a first component relative to a second component, substantially along a common linear axis, in a first direction and/or second direction, but not necessarily consecutively in both directions during a single manipulation period.) The latching collet mechanism of the riser disconnect may be manipulated between the collet latch position and the collet unlatch position by alternately applying tension and releasing tension in the riser disconnect by the drilling rig.
[0015] In an initial installation, the riser latch mechanism, including the collet mechanism, may be positioned in the collet latch position. After the riser system is installed and cemented in position within the well bore, tension may be applied to the riser system at the riser disconnect to securely retain the latched engagement between the male and female disconnect members.
[0016] To disconnect the male and female disconnect members, such as in advance of an approaching storm, tension in the riser disconnect may be relaxed allowing the male disconnect member to move axially downward relative to the female disconnect member, thereby unlatching the collet mechanism. The upper riser may be subsequently raised, separated from and suspended above the lower riser. The rig may then be moved and/or the upper riser recovered to the rig.
[0017] To reconnect the riser disconnect, the male disconnect member may be guided by the entry guide into engagement with the female disconnect member and the collet mechanism re-latched. Tension may be applied and maintained in the riser system to retain the latched configuration during operations until it is desirable to again disconnect the riser disconnect system. Upon completion of well work operations, the female disconnect member with the male disconnect member (plus a subsea riser valve, if run) may be typically recovered together by normally cutting the riser below the mud line with either an explosive charge, a chemical cutter or a mechanical cutter.
[0018] If desired, the riser disconnect and lower riser may be drilled into position in the sea bed while the well bore for the lower riser is being drilled. This may be accomplished by a number of means, for example preferably by positioning the lower riser on the sea bed with a riser disconnect and portions of an upper riser attached or to be attached substantially during drilling operations, and running a string of drill pipe, a drill bit and/or an under reamer bit through the deployed riser assembly and rotating the riser string with the bit while drilling the lower riser into the seabed. Alternatively, the drill string may substantially swivel or rotate within the riser while the riser may not rotate or may rotate independently from the drill string, while drilling the lower riser into the sea bed for cementing and permanent placement of the lower riser. The drill bit and drill string may then be retrieved back to the rig. Those skilled in the art of well drilling operations will appreciate that there are a number of other means for drilling in the lower riser. An alternative embodiment for the riser disconnect provides non-rotational engagement grooves in order to rotate the riser with the drill string.
[0019] In an another alternative embodiment, the upper riser may include the female disconnect member and related components, while the lower riser provides the male disconnect member and related components. An alternative embodiment may also provide the seal members within the female member while the male seal member provides a substantially smooth sealing surface on a mandrel.
[0020] It is an object of the present embodiment to improve the economics of drilling, completion and work over operations from an offshore rig by providing a more economical method of equipment optimization and use. An embodiment provides apparatus and means for placing the wellhead and BOP system substantially on the rig. In a preferred installation, a riser system may be utilized which employs riser joint connections secured by means and apparatus other than by flanges and bolting, such as a threaded riser consisting of joints of well casing, or a groove locked connection. Such equipment usage and arrangement may also save a considerable amount of time in retracting and deploying the upper riser. In addition, a flex joint may be provided either above or below the riser disconnect to accommodate riser angular displacement.
[0021] It is also an object of this embodiment to provide apparatus and means to relatively quickly disconnect an upper riser from a lower riser to facilitate moving the rig out of harms way. This embodiment provides a riser disconnect system which may be actuated by merely reciprocating the upper riser relative to the lower riser.
[0022] It is further an objective of this embodiment to provide a riser disconnect apparatus which may be easily and reliably manipulated from the rig. Manipulation of the riser disconnect between the riser latch position and the riser unlatch position may be performed by simple axial reciprocation of the riser disconnect from the rig. Moving the BOP stack near the rig may also assist in economic riser deployment and recovery.
[0023] It is a feature of this preferred embodiment to provide a riser disconnect system which may be reconnected after disconnecting the male and female disconnect members. The riser disconnect system of this embodiment may be repeatedly connected and disconnected.
[0024] It is another feature of this embodiment that the riser disconnect may be manipulated between the connected and disconnected positions without subsurface hydraulic and/or electrical umbilical lines. Although such lines may optionally be employed for other purposes, the riser disconnect does not require them.
[0025] It is also a feature of this embodiment that the riser disconnect system may be locked in the riser latch or unlocked from the riser latch position. The riser system, including the riser disconnect may be installed while the riser disconnect is locked in the latched position, and after installation the riser disconnect may preferably remain unlocked, while riser tension maintains the disconnect in a latched configuration.
[0026] These advantages may enhance deep water operations by facilitating employment of an improved, more cost effective riser and drilling system which may save considerable time and costs. The subsea riser disconnect may provide for placing the BOP stack on or suspended just below the rig or drill ship, thereby effectively eliminating placing the BOP stack on the ocean floor. By minimizing the number of subsurface hydraulic and electric umbilical lines, connectors, and kill and choke lines, several days of rig time may be saved. The preferred drilling equipment configuration and alternative embodiments thereof, as disclosed herein, may be particularly applicable for drilling and completing exploratory or other wells where well costs are a key consideration and where the well may not be intended for production after well testing.
[0027] It is also a feature of this embodiment that the riser disconnect system may be employed with re-entry risers as well as drilling and completion risers. Although the preferred embodiment is illustrated generally in terms of use with a drilling riser installation, the concepts and apparatus for riser disconnect manipulation by axial reciprocation methods may be applied equally well to risers used in completion and re-entry operations following well completion.
[0028] Subsea Riser Valve
[0029] A preferred embodiment of a subsurface riser valve includes an apparatus and methods for sealing the interior of a well bore, below the riser valve, through axial movement of the riser above the riser valve (generally, the upper riser) relative to the riser below the riser valve (generally, the lower riser). The subsea riser valve may be positioned at substantially any point along a riser system, preferably below the riser disconnect such that the riser valve may be closed in conjunction with or prior to disconnection of a riser disconnect. The subsea riser valve may also provide a subsea method of well control, such that the BOP stack may be positioned on the rig.
[0030] A preferred embodiment of the subsurface riser valve provides for the riser valve as a distinct, stand-alone piece of equipment which may be employed separately or in combination with riser and/or drill pipe disconnect apparatus. The riser valve is preferably used in combination with the riser disconnect, such that the riser valve is positioned below the riser disconnect in order that the interior of a lower riser and well bore below the riser valve may be hydraulically isolated and confined. The lower end of a riser valve may be sealingly connected to the upper end of a lower riser, a well casing, a well head or other subsea component. The upper end of the subsea riser valve may be directly or indirectly secured to the lower end of the subsea riser disconnect.
[0031] The subsea riser valve includes a valve housing enclosing a valve sealing member, and a valve actuation mandrel telescopically extending from the upper portion of the riser valve. A linkage or connector may moveably connect the valve sealing member and the valve actuation mandrel. The riser valve may be biased closed and may be opened in response to axial tension in the riser system. A lockout device similar to the lockout device described on the riser disconnect above, may be included with the riser valve apparatus, to lock the riser valve in either the valve opened or valve closed positions.
[0032] The riser valve may be locked in the opened position during installation of the riser system to allow the riser to fill with fluid and to allow circulation of fluids or slurries through the string prior to applying tension in the valve system. When the riser valve and riser system are properly positioned, installed and cemented, tension may be exerted on the riser valve to maintain the valve sealing member in the valve opened position. Prior to closing the valve sealing member, components within the through bore of the riser valve may be removed from within the through bore of the riser valve, such that the valve sealing member may freely move between the valve closed and valve opened positions.
[0033] It is an objective of this embodiment to provide an apparatus and means for sealing the interior of a riser and well bore below the riser in response to axial motion of the upper riser string. To close an opened valve sealing member, axial tension in the riser system may be relaxed such that the weight of the riser and the resulting closing biasing force may close the riser valve, effectively sealing the well bore below the riser valve. To open the riser valve, axial tension may be applied to the upper riser and valve actuation mandrel sufficient to overcome the riser weight and closing bias force. The riser valve may be opened and closed repeatedly as needed during well operations.
[0034] It is an object of this embodiment that the riser valve may be used in conjunction with the riser disconnect to provide a mechanically actuated riser disconnect and well control system for connecting a drilling rig to a subsea well bore. Such mechanically actuated system may assist in facilitating placing the BOP stack and related well control equipment on or near the drilling rig. Such arrangement may significantly decrease well costs by eliminating hydraulic and/or electrical umbilical lines between subsea equipment and the rig. Concurrent and subsequent axial movement of the riser may also unlatch and disconnect the upper riser from the lower riser. The rig and upper riser may thereafter be removed from the situs of the well, while the subsea well control valve remains to contains well pressure and fluids within the well bore.
[0035] It is also an object of this embodiment to provide a subsea riser valve which may be manipulated between the opened and closed positions without hydraulic or electrical lines. Mechanical movement within the valve mechanism is provided by axial movement of the riser system, thereby effectively eliminating the need for hydraulic or electrical actuation of the valve sealing member.
[0036] It is a feature of this embodiment that the riser valve provide a full bore opening through bore. The preferred riser valve, including the valve sealing member may provide an ID that is not less than the minimum ID of either or both of the upper riser and lower riser.
[0037] It is another feature of this embodiment that the preferred riser valve may be provided as a separate, stand alone device, such that the riser valve may be used alone in a riser system, or a riser disconnect may be combined with a stand-alone riser valve and/or other separate devices. Alternatively, the riser valve may be integrated into a common housing with a riser disconnect apparatus. Both apparatus may be compatible for use as an integrated tool combining both the riser valve and the riser disconnect in a common housing or body, as both may be compatibly manipulated by axial tension applied at the drilling rig.
[0038] It is also a feature of this embodiment that the riser valve may be installed inverted from the preferred orientation described above, such that the valve actuation mandrel is connected to the lower riser, casing or well head. In either the preferred or an inverted embodiment, the riser valve may be manipulated with tension in the upper riser.
[0039] An additional feature of other embodiments of this invention is that the riser valve components may be varied such that the valve sealing member may be of a type other than a ball type sealing member, such as plug type rotational cylinder members, or gate type sealing members, or flapper type sealing members. Alternative embodiments for a riser valve may be configured for manipulating each of these types of sealing members from axial movement of the upper riser relative to the lower riser.
[0040] Drill Pipe Disconnect
[0041] Apparatus and method are disclosed for connecting and disconnecting an upper portion of a drill pipe string above a drill pipe disconnect apparatus from a lower portion of a drill pipe string below the disconnect apparatus. The drill pipe disconnect may be positioned at substantially any point along the drill string wherein it may be convenient or desirable to disconnect a portion of the drill pipe string from the remainder of the string. Such disconnection may be required in conjunction with disconnecting a subsea riser disconnect, and/or in conjunction with closing a subsea riser valve, such as may be desirable in advance of relocating the rig due to approaching threatening weather.
[0042] The drill pipe disconnect is preferably used in conjunction with the subsea riser disconnect and/or the subsea riser valve. Prior to closing a riser valve and/or disconnecting a riser disconnect, rather than pull the entire string of drill pipe above the riser valve, it may be prudent to temporarily abandon the portion of the drill pipe string which is below the riser valve and the drill pipe disconnect. In such event, the drill pipe disconnect may be disconnected at a point below the riser valve, and the upper disconnected portion of drill pipe pulled up to above the riser valve, such that the riser valve may be closed and the riser disconnect subsequently disconnected.
[0043] The drill pipe disconnect may be selectively operable to mechanically disconnect or connect the upper and lower portions of a drill pipe string, in response to movement of a latch mechanism, while also providing axial and rotational strength commensurate with the strength of the drill pipe in use. Non-rotational engagement components may be included within the drill pipe disconnect to carry rotational stresses in the drill string.
[0044] A preferred embodiment of a drill pipe disconnect apparatus may generally include a male drill pipe disconnect member and a female drill pipe disconnect member. The male disconnect member may include a collet mechanism to latch and unlatch the male and female disconnect members. A latch sleeve may be included, which is movable between a collet latch position and a collet unlatch position. When the latch sleeve is in the collet unlatch position, the male drill pipe disconnect member may be released from engagement with the female drill pipe disconnect member.
[0045] The male and female disconnect members of the drill pipe disconnect may be secured within a drill pipe string by connections provided on each end of the drill pipe disconnect. In a preferable embodiment, the upper end of the male disconnect may include a threaded box type tool joint, while the lower end of the female disconnect may include a threaded pin type tool joint.
[0046] A preferred method of operation for the drill pipe disconnect generally includes providing and operating a first assembly and a second assembly, which is a modification of the first assembly. The first assembly may typically be employed for an initial drill pipe disconnect installation. Thereafter, subsequent to disconnecting the drill pipe assembly and recovering the male drill pipe disconnect member to the rig, the second assembly may be installed. The second assembly is provided by substituting a male reconnect member for the male disconnect member, to reconnect the male reconnect member with the female disconnect member. Thereafter, if desired the male reconnect member and the female disconnect member may be re-unlatched from one another.
[0047] The first assembly for the drill pipe disconnect may be installed in a drill pipe string, such that the collet mechanism and latch sleeve are in the collet latch position. A shear pin may secure the position of the latch sleeve within a male disconnect housing, in the collet latched position. The string of drill pipe including the drill pipe disconnect may be repeatedly inserted into and withdrawn from a well bore as needed, such as when “tripping pipe,” with the drill pipe disconnect apparatus threadably secured within the drill string.
[0048] In the event it becomes desirable to disconnect the drill pipe disconnect and temporarily or permanently abandon a lower portion of drill pipe within the well bore, an unlatching ball or other closure device may be dropped through the upper portion of drill pipe, from the rig floor. The unlatching ball may sealingly seat on the unlatching seat such that hydraulic pressure may be applied to the drill string from the rig to cause the latch sleeve to shear the shear pin and move downward to a position where the collet dogs may unlatch from engagement with the female disconnect member. The male drill pipe disconnect member may then be telescopically withdrawn from the female disconnect member, and the male disconnect member and upper portion of drill pipe withdrawn to the rig.
[0049] To reconnect the male disconnect member with the female disconnect member, the male second assembly of the male disconnect member may be provided with a positionable latch sleeve that includes two unlatch grooves, shear pins that provide for two shearing actions, a latching seat and an extension tube on the latch sleeve. The male disconnect member may subsequently be engaged with the female disconnect member in the well bore. A latching ball may then be dropped through the drill pipe string for sealingly seating on a latching seat in the latch sleeve. The latching seat may be secured within the latch sleeve by shear pins. Hydraulic pressure may be applied within the drill string, sufficient to shear the double shear pins at a first shear point. The latch sleeve may then move downward from a collet unlatch position to a collet latch position, such that the male and female disconnect members are again securely latched together.
[0050] Hydraulic pressure within the drill string may be further increased to until the shear pins which secure the latch seat within the latch sleeve are sheared, allowing the latch seat and latching ball to be ejected downward from within the latch sleeve. The extension tube on the latch sleeve may receive or catch the ejected latch seat and latching ball. The extension tube may provide a plurality of ports to hydraulically interconnect the upper and lower portions of the interior of the drill pipe. A hydraulic conduit is thereby provided through the drill pipe through bore such that fluid may be circulated through the upper and lower portions of the drill pipe string. The latch seat and latching ball may remain within the extension tube. As an alternative, instead of shearing the latch seat pins and ejecting the latch seat and latching ball and receiving the latch seat and latching ball within the extension tube, the latch ball may be recovered to the surface. Fluid may be circulated down the drill pipe/casing annulus and back up through the drill bit and drill pipe to reverse flow the latching ball back to the surface of the rig.
[0051] In the preferred embodiment, to re-unlatch the male drill pipe disconnect from the female drill pipe disconnect, a re-unlatching ball may be dropped for sealingly seating on a re-unlatching seat. Hydraulic pressure applied within the drill pipe through bore may shear the double shear pins at a second point and allow the latch sleeve to move downward to a re-unlatch position, wherein the male disconnect member may be withdrawn from the female disconnect member and recovered to the rig. For subsequent re-engagement, the male disconnect member may be again re-dressed as described above for reconnection.
[0052] The drill pipe disconnect apparatus and/or method may be utilized in either an off-shore installation or a land based installation. In a land based installation, the drill pipe disconnect may provide for a disconnect point in the drill pipe string, such as may be desirable to provide above a geologic trouble spot or near a casing seat above an open hole section. It may be desirable to provide a convenient disconnect device at a point in the drill string where backing off or disconnecting otherwise may be difficult or impossible to achieve, particularly in deep wells or along long horizontal well bore sections.
[0053] It is an object of this embodiment to provide a method of operation and an apparatus for disconnecting an upper portion of a drill pipe string from a lower portion of the drill pipe string in a quick, reliable manner. The preferred disconnect method and apparatus disclosed herein facilitates providing a relatively simple and reliable disconnection point within a drill pipe string. Some of the components and mechanisms relied upon for operation of this embodiment are recognized as generally reliable mechanisms, such as a collet mechanism, shear pinned components, and ball and seat type hydraulic seals.
[0054] It is also an object of this embodiment to provide a drill pipe disconnect apparatus and method which may be manipulated without relying upon back-off tools, back-off methods, external manipulation devices or destruction of drill pipe to disconnect. This embodiment provides method and apparatus for disconnecting an upper section of a drill pipe string from a lower section of the drill pipe string by dropping a ball and applying hydraulic pressure to unlatch a latch mechanism. The drill pipe disconnect can also be actuated with a portion of the drill string off the bottom of the well bore. To disconnect the drill pipe disconnect mechanism with the drill string off bottom of the well bore, disconnection may only require that a higher pressure be applied to the interior of the drill pipe string above the dropped ball.
[0055] It is a feature of this embodiment that an apparatus and method are provided for reconnecting the upper and the lower drill pipe sections after they have been disconnected. In this embodiment the upper and lower drill pipe sections may be re-engaged and then re-latched by dropping a ball and applying hydraulic pressure to securely re-latch the upper and lower drill pipe sections.
[0056] It is also a feature of this embodiment that the re-latched drill pipe sections may subsequently be unlatched again, thereby facilitating repeated disconnects and reconnects as desired. The drill pipe reconnect and disconnect apparatus and methods are simple and reliable to operate and may save time and costs in disconnecting a drill pipe string at a pre-determined location.
[0057] It is yet another feature of this embodiment that the drill pipe disconnect may provide an apparatus and method for rotating the drill string. Non-rotational engagement members are provided which may provide rotational strength within the disconnect apparatus which is substantially equivalent to the strength of the drill pipe.
BRIEF DESCRIPTION OF THE DRAWINGS
[0058] [0058]FIG. 1 is a simplified pictorial representation of a drilling rig, a riser assembly, a riser disconnect, a riser valve, a string of drill pipe, and a drill pipe disconnect in a drilling installation.
[0059] [0059]FIG. 1A is a pictorial illustration of a riser male disconnect member disconnected from a female riser disconnect member, with an upper portion of drill pipe disconnected from a lower portion of drill pipe.
[0060] [0060]FIG. 2 is a cross-sectional view of an upper portion of a riser disconnect assembly illustrated in cross-section.
[0061] [0061]FIG. 2A is a side view of a riser disconnect lockout as shown in FIG. 2, in a locked orientation.
[0062] [0062]FIG. 3 is a cross-sectional view of lower portion of the riser disconnect assembly illustrated in FIG. 2.
[0063] [0063]FIG. 3A is an enlarged view of a collet mechanism illustrating a collet mechanism in a latched position.
[0064] [0064]FIG. 4 is an enlarged half-section illustration of the riser disconnect collet mechanism generally illustrated in FIG. 3.
[0065] [0065]FIG. 5 is a cross-sectional view of a riser disconnect lockout wherein the left half of FIG. 5 illustrates the lockout mechanism in the locked orientation and the right half of FIG. 5 illustrates the lockout mechanism in the unlocked orientation.
[0066] [0066]FIG. 5A is a side view of the riser disconnect lockout shown in FIG. 2, in cross-section through the lockout pin illustrating retainers, grooves and stop dimples.
[0067] [0067]FIG. 6 is a cross-sectional top view of a riser valve assembly, illustrating a ball pivot and the ball linkage adapter.
[0068] [0068]FIG. 6A is a side view of a ball type sealing member shown in FIG. 6, illustrating an engagement groove and engagement pin arrangement.
[0069] [0069]FIG. 7 is a cross-sectional view of a subsea riser valve assembly, with a valve ball in the opened position.
[0070] [0070]FIG. 8 is a cross-sectional top view of a subsea riser valve assembly illustrating a riser valve lockout device and a valve mandrel guide.
[0071] [0071]FIG. 9 is an enlarged half-sectional view of a subsea riser valve with a valve ball in a closed position.
[0072] [0072]FIG. 10 is a cross-sectional view of a drill pipe disconnect in the collet latched position initially installed, including an unlatching ball.
[0073] [0073]FIG. 11 is a cross-sectional view of the drill pipe disconnect illustrated in FIG. 10, with the latch sleeve moved downward to the collet unlatch position.
[0074] [0074]FIG. 12 illustrates a lower end of a second assembly, a male reconnect member separated from the upper end of a female disconnect member, with the female disconnect member illustrating non-rotational engagement grooves.
[0075] [0075]FIG. 13 is a cross-sectional view of a drill pipe disconnect with the second assembly, a male reconnect member engaged with the female disconnect member, in the collet unlatch position with a latching ball seated.
[0076] [0076]FIG. 14 is an enlarged illustration of the disconnect shown in FIG. 13, with the latch sleeve displaced downward in the collet latch position.
[0077] [0077]FIG. 15 is an enlarged illustration of a portion of the disconnect shown in FIG. 13, with the latch ball and latch seat ejected into the latch sleeve extension.
[0078] [0078]FIG. 16 is a cross-sectional illustration of a drill pipe disconnect with a re-unlatching ball seated and the latch sleeve moved downward to the collet re-unlatch position.
[0079] [0079]FIG. 17 is a cross-sectional view of a drill pipe disconnect collet mechanism illustrating collet dogs engaged with a female disconnect member and illustrating the fingers connecting the latch mandrel with the collet engagement ring.
[0080] [0080]FIG. 18. is a cross-sectional view of a riser disconnect embodiment including a non-rotational key engagement head which is engaged with a non-rotational key.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0081] [0081]FIG. 1 illustrates a generalized, suitable application for a subsea riser disconnect, a subsea riser valve and a drill pipe disconnect according to the present invention. In one embodiment, this invention includes three principle assemblies, namely: 1) a subsea riser disconnect assembly 10 , 2) a subsea riser valve assembly 20 , and 3) a subsea drill pipe disconnect assembly 30 . Each of these three principle assemblies may be provided in a drilling installation, separate and apart from or in combination with any or both of the other principle assemblies, or primary components. As disclosed subsequently, safety mechanisms may be included within each principle assembly to prevent inadvertent operation of that assembly.
[0082] Each of these three primary components 10 , 20 , 30 may be employed individually or in conjunction with one or both of the other primary components. And each of these three components generally include a through bore extending through the component along a central axis 15 . The central axis 15 may substantially be common to each and all components. (It is understood and assumed throughout this disclosure, that all seals may be both hydraulic seals and pneumatic seals, notwithstanding the fact that a particular seal may be simply designated as a hydraulic seal or otherwise. It is also understood and assumed that all connections, secured components, attachments or otherwise joining of two or more components may effect a seal, unless designated otherwise. It is further understood and assumed that the terms drilling rig, rig, work over rig, and drill ship, semi-submersible and related terms may be used interchangeably and not in limitation.)
[0083] One or more portions of a preferred embodiment of a sub-sea riser disconnect assembly 10 are illustrated in FIGS. 1, 1A, 2 and 3 , for sealingly connecting a lower riser 28 extending downward from above the mud line ML through a seabed SB and into a subsea well bore WB with an upper riser 35 extending downward from a drilling rig DR to the lower subsea riser 28 . The drilling rig DR may include floating types of drilling rigs DR such as a drill ship and a semi-submersible rig. The position of the drilling rig DR is not fixed with respect to the location of the wellbore WB. The lower subsea riser 28 may be secured within the wellbore WB, e.g., by a cementing operation, such that the riser disconnect assembly 10 may be selectively activated to disengage and/or reengage a lower end 37 of the upper riser 35 from an upper end 19 of the lower riser 28 .
[0084] The subsea riser disconnect assembly 10 , the subsea valve assembly 20 , the drill pipe 36 , the drill pipe disconnect 30 and the wellbore WB may each include a through bore and a central axis 15 . Both the through bore and the central axis 15 may be substantially aligned along a common central axis 15 .
[0085] The riser disconnect assembly 10 includes a male disconnect member 12 , which may be secured to the lower end 37 of the upper riser 35 , and has a central axis aligned along the axis 15 . The riser disconnect assembly 10 also includes a female disconnect member 18 for axially receiving the male disconnect member 12 therein. The female disconnect member 18 may be secured to upper end 19 of the lower riser 28 . The riser disconnect assembly 10 may provide a full bore opening, such that the minimum ID of the through bore of the riser disconnect assembly 10 is equal to or greater than the ID of at least one of the upper 35 and lower 28 riser sections. Those skilled in the art will appreciate that a riser may generally be comprised of tubular components having a common through bore for providing a conduit that connects a drilling rig DR with a downhole DH portion of a well bore WB that typically extends below the lower end of the riser, where a portion of the lower end of the riser is secured within the seabed, below the mud line ML.
[0086] Riser Disconnect Male Member
[0087] As illustrated in FIGS. 1, 2 and 3 , a seal assembly 14 may provide a pneumatic seal in the connection between the outer surface of the male disconnect member 12 and a mating inner surface of the female disconnect member 18 . The male component of the seal assembly 14 includes an upper seal mandrel 42 , which may be connected to a lower end 19 of the upper riser 35 by a riser connector collar 41 . A lower end of the upper seal mandrel 42 may be connected to an upper end of a lower seal mandrel 56 . The lower end of the lower seal mandrel 56 in turn may be connected to a seal retainer 61 , which may be connected to latch mandrel 62 . The upper end of the latch mandrel 62 may be connected to the lower end of the seal retainer 61 , while the lower end of the latch mandrel 62 may generally include the lower end of the male disconnect member 12 . A commonly known latch J-slot groove 63 , as shown in FIG. 3, may be included in the outer surface of the latch mandrel 62 , and may circumferentially surround the latch mandrel 62 , in either the pattern shown or another desired pattern.
[0088] One or more seal elements 54 , also commonly known as packing elements, may be positioned axially along the outer surface of the lower seal mandrel 56 , between the upper seal mandrel 42 and the seal retainer 61 . The seal elements 54 may circumferentially encompass the outer surface of the lower seal mandrel 56 and may include an alternating arrangement of a variety of seal materials in alternative embodiments. The seal elements 54 need not be axially continuous along the lower seal mandrel 56 , and may be positioned in sets, at axial intervals along the male component and female component. The female component of the seal assembly 14 may include a seal bore receptacle 58 for engaging the seal elements 54 . The female disconnect member 18 is discussed in detail below.
[0089] A riser interconnection device 40 may be included for releasably securing the male disconnect member 12 with the female disconnect member 18 . The riser interconnection device 40 may be actuatable in response to axial reciprocating movement of the upper riser 35 relative to the lower riser 28 from a connect position to a release position or from a release position to a connect position. This reciprocating movement may be effected by movement of the upper riser 35 at the drilling rig DR. In the release position, the male disconnect member 12 and the female disconnect member 18 may be uncoupled, thereby permitting mechanical separation of the upper riser 35 from the lower riser 28 , as discussed below.
[0090] Referring to FIGS. 1 ,3 and 4 , the riser interconnection device 40 may include a collet mechanism 60 for releasably interconnecting the male disconnect member 12 with the female disconnect member 18 . Components of the collet mechanism 60 included in the male disconnect member 12 may include a collet latch sleeve 72 , a latch pin 74 and the collet locking sleeve 80 . The collet latch sleeve 72 may include a plurality of collet arms 76 , and each collet arm 76 may include a collet dog 78 for engaging a collet groove 82 . The collet groove 82 may be provided in the inner surface of a latch housing sleeve 84 of the female disconnect member 18 . The collet latch sleeve 72 , a plurality of collet arms 76 and corresponding plurality of latch dogs 78 may be circumferentially spaced about the external surface of the latch mandrel 62 for selectively interconnecting the plurality of collet dogs 78 with the collet groove 82 . The collet latch sleeve 72 , the plurality of collet arms 76 and the latch dogs 78 may be axially and rotationally moveable about the common central axis 15 , with respect to the latch mandrel 62 .
[0091] One or more latch pins 74 may be secured in the collet latch sleeve 72 . The latch pins 74 may protrude radially inward from the inner surface of the collet latch sleeve 72 toward the central axis 15 for a distance sufficient for the latch pins 74 to engage the latch J-slot groove 63 , in the outer surface of the latch mandrel 62 . The intrusion of latch pins 74 into the J-slot groove 63 may not exceed the depth of the latch J-slot groove 63 . The plurality of collet arms 76 and collet dogs 78 are preferably made integrally part of the collet latch sleeve 72 . The plurality of collet arms 76 and collet dogs 78 extend downward from the collet latch sleeve 72 . The collet locking sleeve 80 may be immovably secured to the lower end of the latch mandrel 62 , below the collet latch sleeve 72 .
[0092] A portion of the collet locking sleeve 80 may extend axially upward along the outer surface of the latch mandrel 62 for a sufficient distance such that, with the riser disconnect assembly 10 in the latched position, a tapered portion 81 of the collet locking sleeve 80 may be circumferentially positioned between an inner surface of the collet dogs 78 and an outer surface of the latch mandrel 62 . The tapered portion 81 of the collet locking sleeve 80 , which is between the inner surface of the collet dogs 78 and the outer surface of the latch mandrel 62 , may also be referred to as the collet engaging ring 81 . An outer surface of the collet engaging ring 81 includes the tapered surface which may taper upward to a circumferential upper edge. A load bearing shoulder at bottom of the collet dog 78 may be supported on load bearing shoulder at lower end of collet engaging ring 81 of collet locking sleeve 80 when the riser disconnect assembly 10 is in the latched position. A load bearing shoulder at top of the collet dog 78 may be supported on load bearing shoulder at upper end of a collet engagement groove 82 when riser disconnect assembly 10 is in the latched position.
[0093] Riser Disconnect Female Member
[0094] Referring to FIGS. 1, 2, 3 and 4 , the lower riser 28 extends upward from the mud line ML, generally toward the drilling rig DR. The lower end of the lower riser 28 may be connected to a well casing 32 which extends through a seabed and into a subsea wellbore WB. The female disconnect member 18 may include the latch housing sleeve 84 , a seal bore receptacle 58 , and an entry guide 34 . The latch housing sleeve 84 may also include the female portion of the collet mechanism 60 , e.g., the collet groove 82 for coupling with the companion male components of the collet mechanism 60 . A casing end of the latch housing sleeve 84 may be attached to the upper end of a well casing 32 or other component. A latch end of the latch housing sleeve 84 may include a collet groove 82 circumferentially within the inner surface of the latch housing sleeve 84 for releasably receiving and securing the collet dogs 78 of the male disconnect member 12 .
[0095] The latch end of the latch housing sleeve 84 may be attached to the lower end of the seal bore receptacle 58 . An entry guide 34 may be secured to an upper end of the seal bore receptacle 58 , and may assist in aligning the male disconnect member 12 with the female disconnect member 18 during reconnection of the male disconnect member 12 and female disconnect member 18 . An entry guide retainer 52 may be used to secure the entry guide 34 to the seal bore receptacle 58 . The entry guide 34 may extend upward toward the water surface from the point of attachment to the female disconnect member 18 , with a frustoconically expanding circumference, thereby forming a generally cone shaped receptacle defined by surface 38 .
[0096] Riser Disconnect Lockout Mechanism
[0097] In addition to the latch mechanism and seal components, the riser disconnect assembly 10 may include a riser disconnect lockout 50 to prevent inadvertent or unintentional disengagement of the male disconnect member 12 from the female disconnect member 18 . The riser disconnect lockout 50 may typically be used in the locked configuration only during the initial connection, installation and cementing of the upper and lower riser assembly, when compressive forces may be experienced due to running, installing and cementing the casing 32 and/or the riser disconnect assembly 10 . The riser disconnect lockout 50 may otherwise normally remain in the unlocked position since the applied axial tensile forces in the upper riser 35 prevent disconnection of the male disconnect member and the female disconnect member. Referring to FIGS. 2, 2A, the riser disconnect lockout 50 may preferably be comprised of a shouldered pin and groove assembly. The riser disconnect lockout 50 preferably may be provided on the male disconnect member 12 , axially between the riser connector collar 41 and the lower seal mandrel 56 .
[0098] Referring to FIGS. 1, 2, 2 A, 3 , 3 A, 4 , 5 , 5 A one or more lockout grooves 43 may be circumferentially provided on the outer surface of the upper seal mandrel 42 , each lockout groove to accommodate a lockout pin 46 . The one or more grooves 43 may each have a long axis which is aligned axially up and down along the upper riser 35 , substantially parallel with the central axis 15 . Each groove 43 includes a circular portion, at the lower end of the groove 43 , the circular portion having a diameter that is larger than the width of the groove 43 , as shown in FIGS. 2A and 5. A riser disconnect lockout housing 48 may be circumferentially positioned on the external surface of the upper seal mandrel 42 , the riser disconnect lockout housing 48 being axially moveable along the central axis 15 , on the outer surface of the upper seal mandrel 42 .
[0099] A riser disconnect lockout pin 46 may be provided for each lockout groove 43 . Referring to FIGS. 2A, 5, and 5 A, the riser disconnect lockout pin 46 may include a round shaped upset providing lockout upset shoulders 45 and having two opposing flat sides where opposing portions of the round shaped upset are removed to provide the flat sides, on an inner end of the riser disconnect lockout pin 46 , the rounded portion provided along a major axis between the rounded ends and having a length that is larger than the diameter of the pin 46 , and a minor axis between the two flat sides which is substantially equal to the diameter of the pin 46 . Each lockout pin 46 may extend from inside of the riser disconnect lockout housing 48 , through a pin port 51 and may be furnished with a square socket for engagement with an ROV operating wrench (not shown). The round shaped portion of the riser disconnect lockout pin 46 remains inside of the riser disconnect lockout housing 48 in the respective lockout groove 43 .
[0100] As illustrated in FIGS. 5, 5A, spring loaded and/or threaded or otherwise secured retainer pins 49 may be positioned within the riser disconnect lockout housing 48 to engage a retainer groove 53 in each lockout pin 46 to provide resistance to the pin 46 . Such configuration may thereby prevent inadvertent rotation of the pin 46 . In addition, the retainer groove 53 may only be provided circumferentially around a portion of the outer surface of the lockout pin 46 , such as ninety degrees, in order to provide rotational stop positions to ensure proper rotational orientation of the lockout pin 46 . Stop dimples 88 , as shown in FIG. 5A, may be provided on a portion of the lockout pin 46 to ensure proper respective locked and unlocked lockout pin 46 orientation.
[0101] A lockout sleeve 44 may be concentrically disposed around a portion of the upper seal mandrel 42 . An upper end of the lockout sleeve 44 may engage the riser disconnect lockout housing 48 , and a lower end of the lockout sleeve 44 may engage the upper end of the seal bore receptacle 58 . The lockout sleeve 44 is axially moveable with respect to the upper seal mandrel 42 when lockout 50 is in the unlocked position.
[0102] An alternative embodiment for a riser disconnect may include an apparatus to facilitate rotating an upper riser, a riser disconnect and a lower riser, substantially in unison to drill the lower riser into position in the sea bed. A bit 39 or under reamer bit may be positioned near the lower end of the lower riser 28 . Referring to FIG. 18, a tubular, generally female, non-rotational key engagement head 340 may be secured to a female riser disconnect member to receive and engage a non-rotational key member 346 . The non-rotational key member 346 may be secured to an outer surface of a mandrel, such as a lockout sleeve 344 , which may be concentrically disposed around an upper seal mandrel 342 . The female non-rotational key engagement head 340 may include a tapered upper surface, which may be referred to as an upper key guide surface 345 , to guide insertion of the male member into non-rotational engagement with the female disconnect member. An extension mandrel 359 may support the female non-rotational key engagement head 340 and may support an entry guide 334 . An upper end of a seal bore receptacle 358 may connect with the lower end of the extension mandrel 359 . An extension mandrel adapter ring 360 may connect the seal bore receptacle 358 and the extension mandrel 359 . Such embodiment may facilitate rotating a lower riser with an upper riser which may be connected by a riser disconnect 10 . The non-rotational key engagement head 340 and non-rotational key member 346 components, or variations thereof such components, may be employed for purposes other than drilling in the lower riser 28 , such as rotating the lower riser in preparation for and/or during cementing operations, or to rotationally manipulate the lower riser 28 and/or upper riser 35 .
[0103] Riser Disconnect, General Operation
[0104] Referring to FIGS. 1, 2, 2 A, 3 , 3 A, 4 , 5 and 5 A, the riser disconnect assembly 10 , is generally operable by axial motion of the attached upper riser 35 relative to the lower riser 28 , using the drilling rig DR to effect axial motion or reciprocation. The male disconnect member 12 is latched into engagement with the female disconnect member prior to riser installation. When the riser disconnect assembly 10 is installed on a well as part of a riser assembly and in the connected and latched position, the upper riser 35 and lower riser 28 are normally under a tensile load, typically around one-hundred thousand pounds of force, between the drilling rig DR and the well casing 32 that extends into the wellbore WB and is cemented therein. The tapered portion or collet engaging ring 81 is circumferentially spaced between the inside of the plurality of collet dogs 78 and the outer surface of the latch mandrel 62 , causing the collet dogs to be engaged in the collet groove 82 . The tensile load on the male disconnect member 12 is carried through the collet locking sleeve 80 into the collet dogs 78 as a compressive load, through engagement of the collet locking sleeve 80 with the collet dogs 78 . The compressive load in the collet dogs 78 is transferred to the female disconnect member 18 through the engagement of the collet dogs 78 with the collet groove 82 , the collet groove 82 being a component of the female disconnect member 18 . In such riser tensile load configuration, the latch pin 74 is in a latched position 66 within the latch J-slot groove 63 . A load bearing shoulder at bottom of the collet dog 78 may be supported on load bearing shoulder at lower end of collet engaging ring 81 of collet locking sleeve 80 when the riser disconnect assembly 10 is in the latched position. A load bearing shoulder at top of the collet dog 78 may be supported on load bearing shoulder at upper end of a collet engagement groove 82 when riser disconnect assembly 10 is in the latched position.
[0105] The load bearing lockout shoulders 45 of each riser disconnect lockout pin 46 are preferably normally positioned within the circular, lower portion of the respective lockout groove 43 and in a rotational orientation such that a long axis between the rounded end portions 47 of the lockout pin 46 may be axially aligned parallel to a long axis of the lockout groove 43 . In such orientation, the male disconnect member 12 may be unlatched from the female disconnect member 18 . Tensile load in the upper riser 35 may not act directly upon the riser disconnect lockout pin 46 . When in the locked orientation, the lockout pin 46 may prevent any compressive forces in the riser from inadvertently unlocking the riser disconnect assembly 10 , in that the load bearing shoulders 45 are not aligned to move along the lockout grooves 43 , as is otherwise required to disconnect the riser disconnect assembly 10 . The locked orientation may normally be used only in initial installation of the casing 32 , riser disconnect assembly 10 . Otherwise the lockout pin 46 will typically remain in the unlocked orientation.
[0106] When the riser disconnect lockout 50 is in the locked position, as illustrated in the left half of FIG. 5, compressive forces in the upper riser 35 prohibit an unlocking axial movement of the upper riser 35 relative to the lower riser 18 . Compressive forces tending to axially move the upper riser 35 relative to the lower riser 28 , such as may be experienced during riser installation, will transfer from the upper seal mandrel 42 to the load bearing lockout shoulders 45 of the lockout pin 46 , and from the lockout pin 46 to the riser disconnect lockout housing 48 . When applying compressive forces substantially at the riser disconnect assembly 10 , the riser disconnect lockout housing 48 will compressingly engage an upper portion of the lockout sleeve 44 , which in turn will compressingly engage an upper portion of the seal bore receptacle 54 . The seal bore receptacle 54 is an immovable component of the lower riser 28 . If the lockout pin is in the unlocked orientation, axial movement of the upper riser 35 relative to the lower riser 28 will result, thereby permitting disconnecting the riser disconnect assembly 10 . If the lockout pin 46 is in the locked orientation, substantially no axial movement of the upper riser 35 relative to the lower riser 28 will result, thereby preventing inadvertent disconnecting of the riser disconnect assembly 10 . The lockout pin 46 is preferably in the locked orientation during running and installation of the casing 32 , the lower riser 28 and upper riser 35 . After cementing operations are complete and tension is applied to the riser disconnect assembly 10 , a remotely operated vehicle (ROV), diver or other means may be employed to orient the disconnect lockout pin 46 to the unlocked orientation. Well operations may normally be carried on with the riser disconnect lockout 50 in the unlocked orientation.
[0107] Riser Disconnect, Unlatching and Disconnecting Operation
[0108] In the embodiment illustrated in FIGS. 1, 2, 2 A, 3 , 3 A, 4 , 5 and 5 A, to unlatch and disconnect the upper riser 35 from the lower riser 28 , the tensile load in the riser assembly may be relaxed and converted to a compressive load at the riser interconnection device 40 . If the lockout pin 46 is oriented in the locked position the riser disconnect lockout 50 must be unlocked, such as by ROV or diver, before the riser disconnect operation may be performed. The load bearing shoulders 45 of each riser disconnect lockout pin 46 , which are positioned within the circular, lower portion of the respective lockout groove 43 , may be rotated 90 degrees to a rotational orientation where the long axis portion of the lockout pin 46 providing the load bearing shoulders 47 , is aligned parallel to the long axis of each respective lockout groove 43 . When the riser disconnect lockout pin 46 is oriented in the unlocked position, axial downward displacement of the upper seal mandrel 42 relative to the lockout sleeve 44 is permitted, such that each lockout groove 43 in the upper seal mandrel 42 may axially move along the respective lockout pin 46 during the axial disconnect movement of the upper riser 35 .
[0109] As the upper riser 35 is axially moved downward, the male disconnect member 12 moves downward within the female disconnect member 18 . Such displacement results in relative movement of the latch J-slot groove downward along the latch pins 74 . As downward movement continues, the latch pins 74 move from the latched position 66 in the latch J-slot groove 63 to the collet disengage position 64 , and the collet latch sleeve 72 , the latch pin 74 , the plurality of collet arms 76 and the collet dogs 78 move axially and rotationally to the collet disengage position 64 . As the latch mandrel 62 and connected collet locking sleeve 80 move downward, the tapered portion or collet engaging ring 81 of the collet locking sleeve 80 is moved downward and out from between the collet dogs 78 and latch mandrel 62 . The collet dogs 78 may thereby move radially inward toward the latch mandrel 62 and out of engagement with the collet groove 82 . At that point, the male disconnect member 12 is unlatched from the female disconnect member 18 , but is not disconnected.
[0110] To disconnect the male disconnect member 12 from the female disconnect member 18 , an axial tensile force is applied by the drilling rig DR or other means, to the upper riser 35 . As the upper riser 35 moves upward relative to the lower riser 28 , the J-slot groove 63 in the latch mandrel 62 moves upward relative to latch pins 74 , from the collet disengage position 64 to the latch disconnect position 68 . Because the latch disconnect position 68 is relatively higher than the latch connect position 66 , the collet latch sleeve 72 and collet dogs 78 are prohibited from moving downward along the outer surface of the latch mandrel 62 sufficiently to permit the collet dogs 78 to engage the collet locking sleeve 80 . Thereby, during disconnection of the upper riser 35 from the lower riser, the collet dogs remain disengaged in the annulus between the outer surface of the latch mandrel 62 and the inner surface of the seal bore receptacle 58 . The components of the male disconnect member 12 , including the riser disconnect lockout 50 , the upper and lower seal mandrels 42 , 56 , the seal elements 54 , the riser interconnection device 40 and the collet mechanism 60 may be extracted from the seal bore receptacle 58 . The upper riser may be suspended from or removed to the drilling rig DR, leaving the lower riser in place on the well casing 32 .
[0111] Riser Disconnect, Re-Connecting and Latching Operation
[0112] In the embodiment illustrated in FIGS. 1, 2, 2 A, 3 , 3 A, 4 , 5 and 5 A, to reconnect and latch the upper riser 35 to the lower riser 28 , the upper riser 35 may be lowered from the drilling rig DR toward the lower riser 28 . The male disconnect member 12 should be guided into and through the entry guide 34 , to compressively set in the female disconnect member 18 .
[0113] As the unlocked male disconnect member 12 is axially moved downward through the female disconnect member 18 , such displacement results in relative movement of the latch J-slot groove downward from the unlatched or disconnect position 68 , along the latch pins 74 . As downward movement continues, the latch pins 74 move from the unlatched or disconnect position 68 in the latch J-slot groove 63 to a top position 67 , resulting in the collet latch sleeve 72 , the latch pins 74 , the plurality of collet arms 76 and the collet dogs 78 moving axially and rotationally on the latch mandrel. As the latch mandrel 62 and connected collet locking sleeve 80 move downward, the collet dogs 78 will engage the collet groove 82 . The male disconnect member 12 may bottom out on an upset surface 87 in the latch housing sleeve 84 .
[0114] To re-latch the riser interconnection device 40 , tension may be applied to the upper riser 35 from the drilling rig DR, such that the upper riser 35 may begin to move upward relative to the lower riser 28 . As the latch mandrel 62 begins moving upward, the latch pins 74 remain alternatively axially immobile, due to the collet dogs 78 engaged within the collet groove 82 . The latch J-slot groove 63 will move upward relative to the latch pins 74 , repositioning the latch pins 74 from the top position 67 to one of the latch engaged positions 66 . As the latch pins 74 approach the latch engaged position 66 , the collet locking ring 81 may circumferentially slide between the inside of the collet dogs 78 and the outside of the latch mandrel 62 . The collet dogs 78 may thereby move radially outward toward the latch housing sleeve 84 , forcing the collet dogs 78 to fully engage the locking groove 82 . At that point, the male disconnect member 12 is securely reconnected and latched into the female disconnect member 18 . Tension is preferably sustained within the upper riser 35 from the drilling rig DR in order to maintain the riser interconnection properly in the latched position.
[0115] The riser disconnect lockout 50 typically remains in the unlocked orientation during drilling operations. In the event it is alternatively desired to lock the riser disconnect lock 50 , a remotely operated actuator, diver or other means are used to reorient the riser disconnect lockout pin 46 to a locked position. From the typically unlocked position, the load bearing shoulders 45 of each riser disconnect lockout pin 46 , which, (with the riser in tension) are normally positioned within the circular, lower portion of the respective lockout groove 43 , may be preferably rotated 90 degrees to a rotational orientation where the long axis of the round portion 47 of the lockout pin 46 which includes the load bearing shoulders 45 , is aligned perpendicular to the long axis of each respective lockout groove 43 . Such locked orientation of the lockout pins 46 prohibits axial downward displacement of the upper seal mandrel 42 relative to the lockout sleeve 44 , thereby locking the riser disconnect in a latched position.
[0116] Alternatively, the riser disconnect assembly 10 and lower riser 28 may be drilled into position in the sea bed while the well bore WB which is to accommodate insertion of the lower riser therein is being drilled. This may be accomplished by a number of means known within the industry. The lower riser 28 , upper riser 35 and the riser disconnect assembly 10 may be rotated substantially in unison, from the drilling rig DR. Additionally, rotating the lower riser 28 may be desirable in the event a ledge is encountered while installing the lower riser, wherein it may be desired to rotate the lower riser in order to assist insertion of the lower riser in a hole or well bore. An alternative embodiment of a riser disconnect assembly 10 for accomplishing such objectives is illustrated in FIG. 18, and disclosed above.
[0117] Alternatively, depending upon water depth, the riser disconnect 10 , the lower riser 28 and/or the upper riser 35 , or a portion thereof as determined by water depth, may be positioned on the seabed. A string of drill pipe 36 , a drill bit 39 and/or an under reamer bit may be deployed through the positioned riser assembly and the drill string 36 may rotate the riser string along with the bit 39 while drilling the lower riser 28 into the seabed. Those skilled in the art of well drilling operations will appreciate that there are a number of other means for drilling in the lower riser 28 .
[0118] In another alternative embodiment of the riser disconnect assembly 10 , the seal elements 54 may be positioned within one or more grooves in the inner wall of the seal bore receptacle 58 , as opposed to being carried upon the generally male component, the lower seal mandrel 56 . In such alternative configuration, the lower seal mandrel may then provide a generally smooth outer surface for insertion and sealing with the seal elements 54 .
[0119] Another alternative embodiment may include a riser flex joint (not shown) connected to the male or female component of the riser disconnect assembly 10 . The flex joint may be connected in the riser string between one of the riser connector collar 41 and one of the upper riser 35 and the lower riser 28 , or between the latch housing sleeve 84 and the other of the upper riser 35 and lower riser 28 , depending upon orientation of the riser disconnect assembly 10 .
[0120] As an alternative to use with floating drilling rigs DR, such as semi-submersibles and drill ships, the subsea riser disconnect may be used with other types of drilling rigs, such as submersibles, drilling barges or jack-up type drilling rigs. In the event the riser disconnect point is sufficiently far above the mud line, when the riser disconnect is disconnected, buoyancy cans (not shown) may be attached to the lower riser below the riser disconnect and above the mud line ML. Other alternative embodiments may provide for employing an embodiment of the riser disconnect assembly on production wells, development wells and wells other than exploratory or test wells.
[0121] Riser Valve Assembly
[0122] [0122]FIGS. 1, 6, 6 A, 7 , 8 and 9 illustrate a suitable embodiment for a subsea riser valve assembly 20 according to the present embodiment. The subsea riser valve assembly 20 may be used as a stand alone device in a subsea riser installation or may be used in conjunction with the subsea riser disconnect assembly 10 . In an installation where the subsea riser valve assembly 20 is employed in conjunction with the subsea riser disconnect assembly 10 , the two components may be configured as a common component assembly, as generally illustrated in FIG. 1, or preferably as two separate component assemblies, as generally illustrated in FIGS. 2, 3, 7 and 9 . The riser valve assembly 20 may provide a full bore opening when the valve seal element is in the opened position, such that the minimum ID of the through bore of the riser valve assembly 20 is equal to or greater than the ID of one or both of the upper 35 and lower 28 riser. The riser valve assembly 20 may provide a method for isolating the lower riser 28 prior to disconnecting and removing the upper riser 35 from the lower riser 28 , and thereby closing in the well bore WB below the riser valve assembly 20 .
[0123] Those skilled in the are will appreciate that a riser valve 20 is generally a part of a riser system that includes an upper 35 and lower riser 28 , and that the riser valve may thereby include components generally having tubular properties, such as a through bore. Additionally, it may be appreciated that the riser valve 20 may include components which may be similar to components found in valves.
[0124] In an application wherein the riser valve assembly 20 is a distinctly separate component from the riser disconnect assembly 10 , the subsea riser valve assembly 20 may be preferably installed in an upper portion of the lower riser 28 . The lower riser 28 may be comprised of well casing 28 , which extends downward through a seabed and into the subsea wellbore WB where the lower riser is secured by cementing the lower riser 28 within the wellbore WB. The lower riser 28 may include or may be partially comprised of threaded well casing pipe 32 .
[0125] The subsea riser valve assembly 20 may include components for selectively closing off the through bore in the lower riser, thereby hydraulically isolating and enclosing the interior of the lower riser 28 and the wellbore WB below the lower riser 28 . FIG. 7 illustrates a cross-sectional view of a preferred embodiment for a subsea riser valve assembly 20 , with the riser valve assembly 20 in the opened position. FIG. 9 illustrates an enlarged half-section view of the riser valve, with the riser valve assembly 20 in the closed position. A preferred embodiment includes valve housing components 110 , 112 , 114 , and 134 , a valve sealing member 120 , a valve actuating mandrel 118 , and components 128 and 130 which connect the valve actuating mandrel 118 and the valve sealing member 120 . The subsea riser valve assembly 20 may be actuated between the valve opened position and the valve closed position by axial movement of the upper riser 35 relative to the lower riser 28 , by the drilling rig DR or by other means. The riser valve assembly 20 preferably is designed to fail closed such that tension on the riser assembly and the subsea riser valve assembly 20 is required to maintain the subsea riser valve in an opened position. Thus, under normal operating conditions, the subsea riser valve requires tensile force between the upper and lower ends of the riser valve assembly 20 . Releasing the tension or compressing the riser string at the riser valve assembly 20 may preferably result in closure of the riser valve assembly 20 .
[0126] Referring to FIGS. 1, 6, 6 A, 7 , 8 and 9 , a preferred orientation for the subsea riser valve provides for installing the subsea riser valve assembly 20 with the valve actuating mandrel 118 connected to the upper riser 35 and with a lower valve housing 110 connected to the casing 32 extending below the mud line ML, with the casing 32 comprising a portion of the lower riser 28 . In such orientation, a lower end of a lower valve housing 110 may be secured, such as by threaded connection, to an upper end of a well bore casing 32 . A lower end of a central valve housing 112 may be secured, such as by threaded connection, to an upper end of the lower valve housing 110 . An upper valve housing 114 may be secured to an upper end of the central valve housing 112 , while a lower end of a valve mandrel housing 116 may be secured to an upper end of the upper valve housing 114 . A lower end of the valve actuating mandrel 118 may telescopically penetrate the upper end of the valve mandrel housing 116 and into an upper end of the upper valve housing 114 . An upper end of the valve actuating mandrel 118 may be secured to the lower end of the upper riser 35 .
[0127] The riser valve assembly 20 includes a valve sealing member 120 that may be actuated in response to movement of the valve actuating mandrel 118 . In a preferred embodiment, the valve sealing member 120 is a ball type sealing member, being rotatable about a ball axis 121 . Ball pivots 126 may extend along the ball axis 121 , from the generally spherically shaped valve sealing member 120 to maintain orientation during rotation of the sealing member 120 between a valve opened position and a valve closed position. The ball type sealing member 120 includes a through bore that provides a generally continuous through bore through the riser assembly and the riser valve assembly 20 , when the riser valve is in the valve opened position.
[0128] The valve sealing member 120 is generally positioned between the upper 114 and lower 110 valve housings, and within the central valve housing 112 . The valve sealing member may move rotationally on the ball pivots 126 , which in turn may be mounted within one or more ball mounts for supporting the ball pivots 126 during valve manipulation. The upper portion of the lower valve housing 110 may include a lower valve seat 122 to provide a hydraulic seal between the lower valve housing 110 and the valve sealing member 120 . An upper valve seat 124 may be included to provide a hydraulic seal between the upper valve housing 114 and the valve sealing member 120 . One or more seat engagement springs 141 may be provided to enhance the hydraulic seal between the valve sealing member 120 and the lower seat 122 . Wafer type corrugated springs, or other types of seal enhancement mechanism may be employed to effect seal enhancement.
[0129] The valve actuating member 118 may be connected with the valve sealing member 120 with a valve link pin 130 and a link pin adapter 128 . The valve actuating mandrel 118 may include an annular support ring 134 with a plurality of valve link sockets 137 , preferably two valve link sockets 137 , providing one on each side of the actuating member 118 . The each respective annular support ring 134 may move axially within one a respective mandrel guide groove 132 , within the inner surface of the valve mandrel housing 116 . The annular support rings 134 may be connected to an upper end of a valve link pin 130 . A retainer 136 may be provided on the upper end of each valve link pin 130 to secure the valve link pin 130 within the its respective valve link socket 137 . The valve link pin 130 may extend downward from the annular support ring 134 and penetrate the upper valve housing 114 through an upper valve housing passageway 117 , and extend below the upper valve housing 114 to connect with a link pin adapter 128 . The link pin adapter 128 may be moveably disposed within the central valve housing 112 to axially reciprocate along a link pin adapter passage 119 . The link pin adapter 128 may include a link pin adapter projection 131 to engage the valve seal member 120 in a seal member engagement groove 133 , as illustrated in FIG. 6A.
[0130] To prevent rotation of the valve actuating mandrel 118 relative to the mandrel housing 116 , one or more mandrel guides 146 may be positioned within corresponding grooves provided in both the outer surface of the valve actuating mandrel 118 and the inside surface of the valve mandrel housing 116 , as illustrated in FIGS. 7 and 8. The mandrel guides may be secured to the mandrel housing 116 with mandrel guide retainers 140 for each respective mandrel guide 146 . The valve actuation mandrel 118 may axially reciprocate along the one or more relatively immovable mandrel guides 146 . A preferred embodiment provides two mandrel guides 146 and two mandrel guide retainers 140 .
[0131] In a preferred embodiment, the riser valve assembly 20 is designed to remain closed until sufficient tension may be applied to the riser valve assembly 20 to actuate the valve sealing member 120 to the opened position. During installation of the riser valve assembly 20 , the lack of sufficient tension may prevent the valve sealing member 120 from remaining in the valve opened position. To retain the riser valve in a valve opened position during riser installation, and at any time subsequent to installation, a riser valve lockout assembly 150 may be included. The riser valve lockout assembly 150 may be provided within the valve mandrel housing 116 to act upon the valve actuating mandrel 118 to prevent axial displacement of the valve actuating mandrel 118 relative to the mandrel housing 116 . The riser valve assembly 20 may be locked or may remain unlocked, when the valve sealing member 120 is in either the valve opened position or the valve closed position.
[0132] Referring to FIGS. 1, 7, 8 and 9 , one or more valve lockout grooves 151 may be circumferentially provided on the outer surface of the mandrel housing 116 , each lockout groove 151 to accommodate a respective lockout device 153 . The combination of a lockout groove 151 plus a lockout device 153 may constitute a lockout assembly 150 . The one or more valve lockout grooves 151 may each have a long axis which is aligned axially up and down along the valve actuating mandrel 118 , substantially parallel with the central axis 15 . Each groove 151 includes a circular portion at the lower end of the groove 151 and at the upper end of the groove 151 , each circular portion having a diameter that is larger than the width of the groove 151 . The riser valve lockout device 153 is axially moveable along the central axis 15 , on the outer surface of the valve actuating mandrel 118 .
[0133] The riser lockout device 153 may include a lockout pin 148 , a lockout pin adapter 154 and a lockout pin connector bolt 152 connecting the lockout pin 148 and the lockout pin adapter 154 . The riser lockout pin 148 may be substantially round shaped with a pair of opposing flat sides, such that the round shoulders may provide a pair of upset shoulders 147 on the riser valve lockout pin 148 . The round ends of the lockout pin 148 may be axially located along a major linear axis through the lockout pin, the long axis having a length that is longer than the length of a minor axis which extends between the flat sides of the lockout pin 148 . The length of the minor axis may be substantially equal to the diameter of the lockout pin adapter 154 . Each valve lockout device 153 may extend from inside of a lockout groove 151 , outward through a pin port 157 in the valve mandrel housing 116 . The rounded end portion 147 of the riser valve lockout device 153 may remain inside of the groove 151 on the outer surface of the riser valve actuating mandrel 118 . In an unlocked orientation, the lockout pin adapter 154 may slide in lockout groove 151 , along a grooved but non-recessed portion 138 of the valve mandrel housing 116 .
[0134] As illustrated in FIG. 8, and generally referring to the illustration depicted in FIG. 5A, spring loaded retainer pins 159 may be positioned within the riser valve mandrel housing 116 to engage a retainer groove 167 and/or stop dimple 88 on an outer surface of each lockout pin adapter 154 and may thereby prevent inadvertent rotation of the lockout device 153 and may assist the ROV, diver or other actuator in properly aligning the upset shoulders 147 on the lockout pin 148 with respect to the lockout groove 151 . The retainer groove 167 and/or stop dimple 88 may only be provided circumferentially around a portion of the outer surface of the lockout pin adapter 154 , such as substantially ninety degree portions of the lockout pin adapter 154 .
[0135] The riser valve lockout assembly 150 functions similar to the riser disconnect lockout disclosed above. As lockout pin 148 is rotated, such as by ROV or diver, within one of the upper or lower circular portions of the lockout groove 151 to the valve locked orientation, the upset shoulders 147 are oriented so as not to be axially moveable through the narrow portion of the lockout groove 151 . The resulting inability of the lockout device 153 to move axially along the lockout groove 151 provides the capability to lock the valve 20 in either a valve opened or valve closed position, depending upon whether the lockout device 153 is engaged in the upper or lower circular portion, respectively, of the lockout groove 151 . This assembly may provide the ability to install the riser valve assembly 20 in either a valve opened or a valve closed position.
[0136] In an alternative embodiment, a valve sealing member may be generally positioned within a valve housing which includes component variations from a valve housing discussed above that includes the upper 114 and lower 110 valve housings, and the central valve housing 112 . In an alternative embodiment, a central valve housing may be included as an integral portion of a lower valve housing or an upper valve housing.
[0137] Riser Valve Operation
[0138] The subsea riser valve assembly 20 is preferably an independent, stand-alone device which may be inter-connected with numerous other devices or related riser components, such as the riser disconnect, a riser flex joint, or other subsea equipment. The riser valve assembly 20 is preferably installed in tandem with the riser disconnect assembly 10 , such that the riser disconnect is positioned axially above the riser valve assembly 20 . Both assemblies, 10 , 20 , are generally inter-connnectably and operationally compatible, as both may be actuated through application and/or reduction of axial tensile force. FIG. 1 generally illustrates a preferred embodiment for a riser valve assembly 20 installation.
[0139] A subsea riser valve assembly 20 as illustrated in FIGS. 1, 6, 7 , 8 and 9 , may be actuated through riser axial reciprocation at the drilling rig DR. The lower valve housing 110 of the riser valve assembly 20 may be connected to the upper end of a lower riser 28 . The lower riser 28 may be comprised of one or more joints of well casing pipe 32 of sufficient length that the lower riser 32 may be positioned within a well bore WB such that an upper portion of the lower riser 28 and the riser valve assembly 20 remain externally accessible above the mud line ML to an ROV, actuator or diver, e.g., to lock or unlock the valve lockout assembly 150 . The upper end of the valve actuating mandrel 118 may be directly or indirectly secured to the upper riser 35 , which extends substantially from the riser valve assembly 20 to the drilling rig DR.
[0140] The riser valve assembly 20 is preferably actuated to mechanically fail closed and to remain in the valve closed position, in the absence of a tensile force applied to the riser valve assembly 20 to maintain the riser valve assembly 20 in the opened position. During installation, the riser valve assembly 20 may be positioned in the valve opened orientation and the lockout device 153 rotated to the locked position, within the lower circular portion of the lockout groove 151 , to allow fluid to fill the upper 35 and lower 28 risers and to facilitate circulation of fluids, slurrys and/or cement through the upper and lower riser.
[0141] The lower riser 28 may be anchored within the well bore WB by placing cement in the annulus between the well bore WB and the outer surface of the well casing 32 . After the cement hardens, tension may be applied by the drilling rig DR, to the upper riser 35 , the riser disconnect assembly 10 , the riser valve assembly 20 and the portion of the lower riser 28 that is not cemented in the well bore WB. When tension is applied to the subsea riser valve assembly 20 , the valve lockout device may be rotated to the valve unlocked position. The riser lockout device 153 preferably remains rotationally oriented in the unlocked position during drilling and well work operations, such that the riser valve assembly 20 may be closed within a relatively short period of time by releasing tension in the upper riser 35 .
[0142] Referring to FIGS. 6, 6A, 7 , 8 and 9 , during riser valve assembly 20 closing operations, as tension is released in the upper riser 35 the weight of the upper riser 35 may provide an axially downward force acting upon an upper portion of the valve actuation mandrel 118 . The downward compressive forces acting upon the valve actuation mandrel 118 may cause the valve actuation mandrel 118 to telescopically move downward within the valve mandrel housing 116 and the upper valve housing 114 . Downward movement of the actuation mandrel 118 may be limited by interference between the top of the valve lockout groove 158 and the valve lockout device 153 .
[0143] The link pin adapter projection 131 on the link pin adapter 128 , which is secured to the lower end of the valve link pin 130 , is moveably engaged with the valve sealing member 120 . As the valve link pin 130 moves downward, the link pin adapter projection 131 may act generally tangentially upon the valve sealing member 120 to effect rotation of the valve sealing member 120 from an opened position to a closed position. The mere weight of components above the riser valve assembly 20 , in the absence of tension in the upper riser 35 , may provide a “fail closed” biasing effect to the sealing member 120 . In an alternative embodiment of a riser valve assembly 20 , a separate and/or additional biasing force may be provided, such as a spring, which may also contribute to closing the riser valve assembly 20 . The biasing effect in either the preferred or an alternative embodiment may serve to close the riser valve sealing member 120 on demand or in the event of loss of tensile force, and to maintain the riser valve assembly 20 in a closed position, such as when the upper riser 35 may be separated and removed from the riser valve assembly 20 .
[0144] To open a preferred embodiment of the riser valve assembly 20 , tensile force may be applied to the valve actuation mandrel 118 . As the valve actuation mandrel 118 is telescopically extended from within the upper valve housing 114 and the valve mandrel housing 116 , the link pin 130 and link pin adapter 128 , which connect the valve actuation mandrel 118 and the valve sealing member 120 , engage the valve sealing member 120 to cause the valve sealing member 120 to rotate from the valve closed position to the valve opened position. A lower valve seat 122 may form a hydraulic seal between the moveable valve sealing member 120 and the lower valve housing 110 . An upper valve seat 124 may form a hydraulic seal between the moveable valve sealing member 120 and the upper valve housing 114 . On O-ring seal 115 may provide a hydraulic seal between the lower end of valve actuation mandrel 118 and the upper valve housing 114 .
[0145] In an alternative embodiment of a riser valve assembly, the valve sealing member may be of a type other than a ball type sealing member, such as a gate type sealing member, a plug or cylinder type sealing member or a flapper type sealing member. These alternative type of sealing members may require variations and modifications on the linkage apparatuses required to effect valve manipulation between the valve opened position and the valve closed position, by axial motion or reciprocation of the valve actuation mandrel 118 .
[0146] In other alternative embodiments, the riser valve assembly 20 may be inverted from the preferred embodiment, such that the valve actuation mandrel 118 is secured to the well casing 32 and a valve body, such as the lower valve housing 110 , is secured to the upper riser 35 . Axial reciprocation of the upper riser 35 would nevertheless effect movement of the valve body relative to the valve actuation mandrel 118 , thereby effecting manipulation of the valve sealing member 120 between the valve opened position and the valve closed position.
[0147] An alternative embodiment for the subsea riser valve assembly 20 may integrate the subsea riser valve and subsea riser disconnect assembly 10 into a substantially single assembly which includes both components 10 , 20 . In such assembly, both the subsea riser disconnect assembly 10 and subsea riser valve assembly 20 may share common housing components.
[0148] As an alternative to positioning a subsea riser valve assembly 20 substantially adjacent and below a subsea riser disconnect assembly 10 , the subsea riser valve may be installed at any point in a riser assembly, including the lower riser 28 and the upper riser 35 , where it may be desirable to provide a valve for closing off an interior portion of a riser through bore.
[0149] Drill Pipe Disconnect
[0150] [0150]FIGS. 1, and 10 through 17 illustrate suitable embodiment for a drill pipe disconnect 30 according to the present invention. The drill pipe disconnect 30 may be used offshore and onshore, along a string of drill pipe 36 used in drilling a subterranean well. In an offshore installation, the drill pipe disconnect may be employed in a drilling installation which also employs a riser disconnect assembly 10 and a subsea riser valve assembly 20 . In general, the drill pipe disconnect 30 provides a means for selectively disconnecting an upper portion of a drill pipe string 36 from a lower portion of the drill pipe string 36 , while leaving the lower portion of the drill pipe string 36 , e.g., within the well bore WB being drilled. The drill pipe disconnect 30 also generally includes an interconnection means which provides for rotating the drill pipe string 36 and for axially transmitting tension and compression in the drill pipe string 36 , through the drill pipe disconnect 30 .
[0151] The drill pipe disconnect 30 may be hydraulically or otherwise actuated between latched and unlatched positions. After disconnection of the drill pipe disconnect 30 , the drill pipe disconnect 30 may be reconnected, e.g., by hydraulic actuation of the latch mechanism.
[0152] In a preferred embodiment, a drill pipe disconnect 30 may be employed in a subsea installation and in conjunction with a subsea riser disconnect assembly 10 and a subsea riser valve assembly 20 . The drill pipe disconnect 30 may be secured within the drill pipe string 36 such that when a drill bit 39 or lower end of the drill pipe string 36 is on or near the bottom of the well bore WB, the drill pipe disconnect 30 may be positioned below the subsea riser valve assembly 20 and the riser disconnect assembly 10 . In such configuration, the drill pipe string 36 may be disconnected at the drill pipe disconnect 30 , and the upper portion of the drill pipe string 36 may be pulled above the subsea riser valve assembly 20 in order that the subsea riser valve assembly 20 may be closed, thereby sealingly isolating the well bore WB and the lower portion of the drill pipe string 36 within the well bore WB.
[0153] A preferred embodiment of the drill pipe disconnect 30 , as illustrated in FIGS. 10 through 17, provides for male and female interconnection components. In addition, the preferred embodiment provides for a non-rotational engagement mechanism to facilitate rotational strength in the drill pipe disconnect 30 , and a collet mechanism for providing axial engagement and disengagement of the male and female interconnection components. The male interconnection component may generally be referred to as the male disconnect member 205 , while the female interconnection component may generally be referred to as the female disconnect member 215 . Each of the male disconnect member and female disconnect may include a through bore and a central axis 215 which may be a common to the disconnect members when the drill pipe disconnect 30 is connected.
[0154] The male disconnect member 205 may be secured to the lower end of an upper portion of drill pipe 236 . An upper end of an upper latch sleeve housing 210 may be secured to the lower end of the upper portion of drill pipe 236 . The lower end of the upper latch sleeve housing 210 may be secured to the upper end of a male drill pipe disconnect housing 212 . A lower end of the male drill pipe disconnect housing 212 may be secured to the upper end of a latch mandrel 222 . The lower end of the latch mandrel 222 may include a latch mandrel collet engaging ring 237 . (Referring to FIGS. 10 and 17, the latch mandrel collet engagement ring 237 is preferably an integral portion of the latch mandrel 222 , which is distinguished with a separate component number ( 237 ) and name to assist in clarifying this disclosure.) A latch sleeve 216 may be moveably positioned within the through bore of the male disconnect member 205 . The outer surface of the latch sleeve may be moveably engaged with the inner surfaces of each of the upper latch sleeve housing 210 , the male drill pipe disconnect housing 212 , the latch mandrel 222 and the latch mandrel collet engaging ring 237 . The lower end of the latch sleeve 222 may axially extend below the lower end of the latch mandrel collet engaging ring 237 , such that the lower end of the latch sleeve 216 defines the lower end of the male disconnect member 205 .
[0155] A collet mechanism 230 may be included on the male disconnect member 205 for selectively securing and unsecuring the male disconnect member 205 with the female disconnect member 215 . The collet mechanism 230 includes a collet ring secured to and circumferentially encompassing a portion of the outer surface of the latch mandrel 222 . A plurality of collet fingers 231 may be spaced circumferentially around the latch mandrel 222 , with an upper end of each respective collet finger 231 secured to the collet ring 229 , and a lower end of each respective collet finger 231 secured to a respective collet dog 232 . The plurality of collet dogs 232 may be positioned near the lower end of the latch mandrel 222 , and extend inwardly through square windows 237 positioned in latch mandrel 222 to contact outer surface of latch sleeve 216 such that, in a latched position, the collet dogs 232 may engage the female disconnect member 215 in a collet engagement groove 239 .
[0156] A shear pin retainer ring 218 may be provided radially between the outer surface of the latch sleeve 216 and the inner surface of the male drill pipe disconnect housing 212 , and axially below the upper latch sleeve housing 210 and axially above the latch mandrel 222 . The shear pin retainer ring 218 may house one or more shear pins 220 which engage both the shear pin retainer ring 218 and the latch sleeve 216 for prohibiting the latch sleeve 216 from axial movement until the shear pins 220 are selectively sheared.
[0157] A collet unlatch groove 224 may circumferentially encompass the outer surface of the latch sleeve 216 , such that alignment of the collet unlatch groove 224 with the plurality of collet dogs 232 may provide for radially receiving the collet dogs 232 within the unlatch groove to provide for disconnection of the male disconnect member 205 and the female disconnect member 215 . An axial position of the latch sleeve 216 wherein the collet unlatch groove 224 on the latch sleeve 216 is aligned with the plurality of collet dogs 232 may generally be referred to as a collet unlatch position. When the collet unlatch groove 224 is not aligned with the collet dogs 232 , such that the collet dogs 232 are caused to engage the collet engagement groove 239 of the female disconnect member 215 by an the latch sleeve 216 , such axial position of the latch sleeve 216 may generally be referred to as a collet latch position.
[0158] When the male disconnect member 205 is engaged with the female disconnect member 215 , a male frustoconical surface 244 substantially on the lower end of the latch mandrel collet engaging ring 237 engages a companion female frustoconical surface 234 in the female disconnect member 215 . Engagement of the frustoconical surfaces 234 , 244 provides compressive load bearing shoulders between the male disconnect member 205 and the female disconnect member 215 . Downward axial movement thereafter of the latch sleeve 216 relative to the latch mandrel 222 effects manipulation of the drill pipe disconnect 30 between the collet latch position and the collet unlatch position. During movement of the latch sleeve 216 , the latch sleeve may telescopically and sealingly penetrate a lower portion of the through bore of the female drill pipe disconnect housing 228 axially below the female frustoconical surface 234 . The inner surface 245 of the lower portion of the through bore of the female drill pipe disconnect housing 228 which receives the latch sleeve 216 , in combination with seal 246 may provide a moveable hydraulic seal between the female disconnect housing 228 and the latch sleeve 216 .
[0159] An upper surface of the latch sleeve 216 may include an unlatching seat for sealing engagement with an unlatching ball 208 . Pressurized engagement of the unlatching ball 208 on the unlatching seat may permit shearing of the shear pins 220 and axial downward of movement of the latch sleeve 216 relative to the latch mandrel 222 .
[0160] The outer surface of the latch sleeve 216 may include a circumferential first shear pin retainer ring groove 260 having a first shear pin retainer upper stop surface 264 . The first shear pin retainer ring groove 260 may circumferentially accommodate the shear pin retainer ring 218 . The shear pin retainer ring 218 includes an upper retainer ring stop surface 262 . After shearing the shear pins 220 , axial downward movement of the latch sleeve 216 relative to the latch mandrel 222 , from the collet latch position to the collet unlatch position, is halted by interference between the upper retainer ring stop surface 262 and first shear pin retainer ring groove upper stop surface 264 . Such interference position of the latch sleeve 216 relative to the latch mandrel 222 may properly align the collet unlatch groove 224 with the collet dogs 232 , in the unlatch position, to permit disconnecting the male disconnect member 205 and the female disconnect member 215 .
[0161] The female disconnect member 215 may include a receptacle bore 241 for receiving the male disconnect member 205 . The collet engagement groove 239 may be positioned circumferentially in an inner wall of the receptacle bore 241 . A female non-rotational engagement member 227 , as illustrated in FIGS. 10 and 12, may be included with the female disconnect member 215 for engaging a companion male non-rotational engagement member 226 , the male non-rotational engagement member 226 being a component secured to the male disconnect member 205 . The lower end of the female disconnect member 215 may be engaged with an upper end of the lower portion of drill pipe 240 .
[0162] Seals 246 , 247 , packing or other sealing devices may be included to provide hydraulic seals between the male disconnect member 205 , male reconnect member 225 and female disconnect member 215 , and between the latch sleeve 216 , 266 and the upper latch sleeve housing 210 . It will be apparent to one skilled in the art that a wide variety of seals and component variations are conceivable and may be applied to apparatus and embodiments of this invention. Consequently, not all seals may be illustrated and/or discussed in this disclosure.
[0163] Drill Pipe Disconnect Assembly Configured for Re-Connection and Re-Unlatching
[0164] In a preferred embodiment for the drill pipe disconnect 30 , when the drill pipe disconnect 30 has been disconnected and the male disconnect member 205 recovered to the drilling rig DR, before reconnecting the male disconnect member 205 with the female disconnect member 215 , the male disconnect member 205 may be replaced with a male reconnect member 225 . FIGS. 13, 14, 15 and 16 illustrate a preferred embodiment for the redressed male reconnect member 225 . The redressed male reconnect member 225 generally includes similar components as the original male disconnect member 205 with the following modifications.
[0165] The male drill pipe disconnect housing 212 may be replaced with a male drill pipe disconnect housing 261 which provides ports for insertion of one or more shear pins which may be sheared at two positions on each shear pin (discussed below) or with two separate sets of shear pins. The original latch sleeve 216 is replaced with a latch sleeve 266 that provides an additional collet unlatching groove, referred to as a collet re-unlatching groove 274 , circumferentially on the outer surface of the latch sleeve 266 and axially above the original collet unlatch groove 224 . The radially raised circumferential surface between the collet unlatch groove 224 and the collet re-unlatch groove 274 may be referred to as the collet latch surface 263 . The latch sleeve 266 includes an additional groove 275 substantially adjacent the first shear pin retainer groove 260 , the additional groove being referred to as the second shear pin retainer groove 275 . The second shear pin retainer groove 275 may be located on the outer surface of the latch sleeve 266 , axially between a bottom surface of the shear pin retainer ring 268 and a latch mandrel upper stop surface 270 , and may circumferentially encompass the outer surface of the latch sleeve 266 . The second shear pin retainer groove 275 may permit movement of the latch sleeve 266 between a collet latch position and a collet re-unlatch position. The shear pin retainer ring 268 may include a port for providing two separate sets of shear pins or a set of double position shear pins 269 . The double position shear pin 269 may extend from a series of aligned ports, from the male drill pipe disconnect housing 261 through the shear pin retainer ring 268 , and into an annular groove in the outer surface of the latch sleeve 266 .
[0166] As illustrated in FIG. 13, a latching seat 285 for sealingly seating a latching ball 286 thereon may be included near the lower end of the latching sleeve 266 , with the latching seat 285 secured to an inner surface of the latch sleeve 266 in the latch sleeve through bore, with the latching seat 285 secured by one or more latching seat shear pins 287 . When latching the male disconnect member 205 with the female disconnect member 215 , the latching ball 286 may sealing engage the latching seat 285 in order that the latch sleeve, may axially move from a collet unlatch position to a collet latch position after shearing the first set or the portion of the double shear pin 269 extending through shear pin retainer 268 into the annular groove in the outer surface of the latch sleeve 266 . Shearing the one or more latching seat shear pins 287 may provide means for ejection of the latching seat 285 and latching ball 286 from within the latch sleeve 266 after movement of the latch sleeve 266 from the collet unlatch position to the collet latch position.
[0167] The upper end of a latch sleeve extension tube 280 may be secured to the lower end of the latch sleeve 266 to receive and retain the latching seat 285 and latching ball 286 after the latching seat 285 and latching ball 286 are sheared and ejected from within the latch sleeve 266 . A plurality of slots or ports 282 may be provided in the latch sleeve extension mandrel 280 to allow circulation of fluid within the through bore of the drill pipe string 36 . A ball and seat catcher 284 may be provided near the lower end of the latch sleeve extension tube 280 to catch and retain the ejected latching seat 285 and latching ball 286 within the latch sleeve extension tube 280 , as illustrated in FIG. 16.
[0168] Alternatively, the latch sleeve 266 may be furnished with an integral non-shearing latching seat 266 and with no latch sleeve extension mandrel 280 . When employing this version of a latch sleeve, the latching ball 286 may be flowed to the surface by reverse circulating fluid after shifting the latching sleeve from the unlatch position to the re-latch position.
[0169] Drill Pipe Disconnect and Reconnect Operation
[0170] Referring to FIGS. 1 and 10 through 16 , in the preferred first embodiment for initial installation of the drill pipe disconnect 30 , the male disconnect member 205 and female disconnect member 215 may be connected as illustrated in FIG. 10, excluding the unlatching ball 208 , and installed in a drill pipe string 36 . The latch sleeve 216 may be axially positioned such that the collet dogs 232 are engaged in the collet engagement groove 239 , thereby securing the male drill pipe disconnect member 205 with the female drill pipe disconnect member 215 . The axial position of the latch sleeve is secured by one or more shear pins 220 . The drill pipe disconnect 30 may be positioned at an axial point in the drill string from which it may be desirable to disconnect, such as below a subsurface riser disconnect assembly 10 , below a subsurface riser valve assembly 20 , or above a trouble spot in a wellbore where it may be desirable to disconnect an upper portion of the drill pipe 236 from a lower portion of the drill pipe 240 .
[0171] To disconnect the male disconnect member 205 from the female disconnect member 215 , the collet mechanism unlatches. Fluid may be circulated through the wellbore WB sufficiently to remove cuttings and other debris. The drill pipe disconnect may be manipulated with the drill pipe set off on bottom, or suspended off bottom in the wellbore by the upper portion of the drill string, thereby allowing the lower disconnected portion of drill pipe to fall subsequent to disconnection. In a preferred embodiment, an unlatching ball 208 may be dropped from the drilling rig DR, through the through bore of the upper portion of drill pipe 236 to sealingly seat on the unlatching seat 209 , on a substantially top surface of the latch sleeve 216 . Pressure may be applied by the drilling rig DR to the through bore of the upper portion of drill pipe 236 to a first release pressure which creates sufficient axial force upon the latch sleeve 216 to shear pins 220 between male drill pipe disconnect housing 212 and latch sleeve 216 to axially move the latch sleeve downward from a collet latch position to a collet unlatch position. In the collet unlatch position, the plurality of collet dogs 232 may move radially inward within the circumferential collet unlatch groove 224 , thereby allowing the male disconnect member 205 to be telescopically removed from the female disconnect member 215 .
[0172] The upper portion of drill pipe 236 may then be recovered to the drilling rig while leaving the lower portion of drill pipe 240 within the well bore WB. To avoid pulling a “wet string,” a drain groove 213 may be provided in the upper portion of the upper latch sleeve housing 210 and one or more drain ports 211 may be provided in the upper portion of the latch sleeve 216 to allow fluid in the upper portion of drill pipe 236 to drain while the upper portion of drill pipe 236 is being removed to the drilling rig DR.
[0173] In a subsea installation, a subsea riser valve may be closed above the female disconnect member 215 in order to confine pressure and fluid with the wellbore WB. In addition, a subsea riser disconnect assembly 10 may be disconnected such that the upper riser 35 may be recovered to the drilling rig DR or the rig may be moved with the upper riser suspended below the drilling rig DR.
[0174] To reconnect the upper portion of drill pipe 236 with the lower portion of drill pipe 240 , the male disconnect member 205 may be replaced or redressed with male reconnect member 225 as described previously. The replaced male reconnect member 225 may be telescopically inserted into the female disconnect member 215 , as illustrated in FIG. 13, excluding the latching ball 286 . During such insertion, the collet dogs 232 may be recessed into the collet unlatch groove 224 on an outer surface of the latch sleeve 266 . The latch sleeve 216 in the male reconnect member 225 may be properly, axially positioned in the unlatch configuration by engagement of upper surface 273 on the outer surface of the latch sleeve 216 and a lower surface of the shear pin retainer 268 . During the telescopic insertion of the male reconnect member 225 into the female disconnect member 215 , the male non-rotational engagement member 226 may telescopically engage the female non-rotational engagement member 227 to facilitate unitary rotation of the drill pipe string 236 , 240 .
[0175] To latch the male reconnect member 225 with the female disconnect member 215 , a latching ball 286 or other closure device, may be dropped or otherwise deployed from the drilling rig DR, through the through bore of the upper portion of drill pipe 236 to sealingly seat on the latching seat 285 . Pressure may be applied to the fluid in the through bore of the upper portion of drill pipe 236 , upon the latching ball 286 and latching seat 285 , to a latching pressure. The latching pressure is sufficient to shear a first shear position on the double position shear pin 269 or first set of separate shear pins, between the latch sleeve and shear pin retainer ring 268 . When the first shear position on the double shear position shear pin 269 shears, or the first set of separate shear pins shears, the latch sleeve 266 may axially move downward from the collet unlatch position to the collet latch position. Downward movement of the latch sleeve 266 may be arrested when the first shear pin retainer groove upper stop surface 264 interferes with or engages the upper retainer ring stop surface 262 .
[0176] At such axial position of the latch sleeve, the collet latch surface 263 on the outer surface of the latch sleeve 266 may engage an inward portion of each collet dog 232 , causing each collet dog 232 to remain positioned radially outward and engage the collet unlatch groove 224 . The collet dog stop surface 233 engages the collet dogs 232 to prohibit axial separation of the male reconnect member 225 and the female disconnect member 215 , and the load bearing shoulder at the bottom of collet dogs 232 may engage a load bearing upper side of the collet engagement ring 237 portion of the latch mandrel 222 , thereby securing the male reconnect member 225 with the female disconnect member 215 .
[0177] After latching the collet mechanism 230 , pressure in the upper drill pipe 236 through bore may be further increased from the latching pressure to a ball and seat ejection pressure. The ball and seat ejection pressure may be sufficient to cause the axial downward force upon the latching ball 286 and latching seat 285 to shear the latching seat shear pin 287 . When the latching seat shear pin 287 is sheared, the latching seat 285 and latching ball 286 may move axially downward through the through bore in the lower portion of the latch sleeve 266 , out of the lower end of the latch sleeve 266 , through an upper portion of the latch sleeve extension tube 280 and into a lower portion of the latch sleeve extension tube 280 . The ejected latching ball 286 and latching seat 285 may be caught within the lower portion of the latch sleeve extension tube 280 and retained therein by the ball and seat catcher 284 . One or more ports 282 through the latch sleeve extension tube 280 may permit transmission of fluid through the drill pipe 36 and drill pipe disconnect 30 through bore, to a bit or other tool on the lower end of the drill pipe 36 . As an alternative to shearing the latching seat 285 and latching ball 286 and ejecting the same into latch sleeve extension tube 280 , the ball 286 may be recovered to the surface by other means, such as reverse circulating fluid or with tools, prior to shearing the seat 285 .
[0178] Such configuration thereby represents the normal operating configuration for a preferred embodiment of the drill pipe disconnect 30 , after reconnection of the male reconnect member 225 with the female disconnect member 215 .
[0179] To disconnect the drill pipe disconnect 30 a second time, as illustrated in FIG. 16, a reunlatching ball may be dropped through the through bore in the upper portion of drill pipe 236 for sealingly seating on the re-unlatching seat 259 , the re-unlatching seat positioned substantially on an upper surface of the latch sleeve 266 . Pressure may be applied in the through bore of the upper portion of drill pipe 236 to a re-unlatching pressure. The re-unlatching pressure may be sufficient to cause the axial downward force on the re-unlatching seat 259 and re-unlatching ball 258 to shear the second set of separate shear pins or the double shear position shear pin at the second shear position. When the second separate set of shear pins or the double shear position shear pin 269 is sheared at the second shear position, the latch sleeve may move axially downward from a collet latch position to a collet re-unlatch position. In the collet re-unlatch position, the collet dogs 232 may be aligned with the collet re-unlatch groove 274 such that the collet dogs may move radially inward toward the latch sleeve 266 and partially recess in the collet re-unlatch groove 224 . Downward movement of the latch sleeve may be arrested by engagement of the lower retainer ring stop surface 271 with the latch mandrel upper stop surface 270 . The male reconnect member 225 may be telescopically withdrawn from the female disconnect member by axial tensile force at the drilling rig DR, permitting recovery of the upper portion of drill pipe 236 to the drilling rig DR.
[0180] Alternative embodiments for the drill pipe disconnect may provide components and means for manipulating components similar to the latch sleeve 216 or 266 other than balls and seats, and hydraulic pressure, such as by mandrel or bars on wire line, or other wireline conveyed tools. Recovery of balls or other manipulating devices may be employed to avoid leaving a ball in the drill pipe disconnect during well drilling or operations, or when pulling the upper portion of drill pipe 236 after disconnecting, to avoid recovering a “wet string.” An alternative embodiment functions by dropping a retrievable device to seal on one or more of the seats for manipulation of the latch sleeve 216 , 266 , which may thereafter be retrieved on wireline to avoid leaving a latching ball in the drill pipe disconnect 30 . A dart or standing valve may alternatively be dropped in lieu of a ball. An embodiment may include means for recovering the latching ball after manipulation of the latch sleeve 266 , such as with a magnet or by reversing fluid flow to retrieve the ball in a catcher or basket for ball retrieval.
[0181] The drill pipe disconnect 30 may be manipulated between latched and unlatched positions, with the drill pipe string 36 set off on bottom of the well bore WB. Also, the drill pipe disconnect 30 may be manipulated between latched and unlatched positions with the drill pipe suspended off of bottom of the well bore WB, in the well bore WB. The weight of the drill pipe suspended below the disconnect may merely require additional hydraulic pressure to disconnect when the drill pipe is suspended off bottom of the well bore WB.
[0182] In alternative embodiments for the drill pipe disconnect 30 , the collet mechanism may be replaced with a different mechanical or hydraulic latch mechanism, such as a grapple type mechanism. Also, the male disconnect member 205 , 225 and female disconnect member 215 may be inverted such that the male disconnect 205 , 225 may be secured to the lower portion of drill pipe 240 and the female disconnect member 215 may be secured to the upper portion of drill pipe 236 . Alternative embodiments may also be assembled with components which interconnect by means other than generally male and female interconnecting components.
[0183] The drill pipe disconnect 30 is generally applicable to drilling wells both onshore and offshore. In addition, although the drill pipe disconnect device is generally referred to herein as a drill pipe disconnect, this device may also be employed with drill pipe used in work over operations, with a “work string” that is generally tubular. The drill pipe disconnect may be positioned below a BOP stack to facilitate disconnecting the drill pipe at a location in the drill string which may be relatively close to the rig, such that subsequently, blind rams may be closed, thereby sealing the interior of the well bore below the BOP stack. Such time saving option may be desirable in a well control situation. Such action may also minimize the amount of pipe that must be tripped out of the well to the rig floor.
[0184] The drill pipe disconnect device may be alternatively adapted for use in setting liners or other downhole tubular members wherein it may be desirable to reliably disconnect an upper portion of tubulars from a lower portion of tubulars to leave the lower portion of tubulars within the wellbore.
[0185] The disconnect device as disclosed herein may also be usefully employed as a safety device for drilling in high risk environments where the risk of sticking pipe, collapsing a well bore, key-seating the drill pipe in the well bore or other drilling hazard risks losing a lower portion of the pipe in the hole. In such instances, this device may be positioned within the tubular string such that the disconnect device may remain above the hazard point to provide a quick and reliable disconnect point uphole from the hazardous well bore region.
[0186] Non-rotational engagement may be alternatively provided by components other than male and female engaging components, such as interlocking keys, dogs or otherwise. Where male and female non-rotational components engaged, the male component may be secured to either the upper portion of drill pipe or to the lower portion of drill pipe, with the female non-rotational engagement component secured to the other of the upper and lower portion of drill pipe.
[0187] The drill pipe disconnect may provide the ability to further extend an “extended reach” well bore beyond the point at which all of a drill pipe string may be recovered to the rig by tensional force. In such instance where an open-hole completion may be economically feasible, a lower portion of the drill pipe string may be abandoned within a lower section of the well bore, and the upper portion of the drill string recovered.
[0188] An alternative embodiment of the drill pipe disconnect may provide for manipulating a latch sleeve by a mechanism other than hydraulically with balls and seats. A latch sleeve may be manipulated by a standing valve, dart or rod that may sealingly engage a seat for hydraulic manipulation of the latch sleeve. Such standing valve, dart or rod may be recoverable on wireline or otherwise, such as reverse pumping the component out of the drill pipe string. A weight bar or rod may engage a load bearing shoulder with sufficient mass weight force to manipulate the latch sleeve. Alternative embodiments may eliminate the latch sleeve altogether and provide for a collet or other latch and unlatch mechanism which does not require a latch sleeve component to effect engagement of the upper and lower disconnect members.
[0189] An embodiment of a drill pipe disconnect may be provided which eliminates the latch seat, latch ball and extension tube, thereby providing an open through bore, through the disconnect tool. Such open through bore may provide access for tools, instruments and materials which would not other wise pass through the ports in the extension tube, to pass through the disconnect device to the lower portion of drill pipe.
[0190] Shear pins may be eliminated in favor of other retainer and release components. The drill pipe disconnect may be configured for manipulation between latch and unlatch positions by a combination of axial, rotational and hydraulic forces. Alternative embodiments may also be configured which provide for replacement of each double shear pin with two separate shear pins.
[0191] The embodiments described herein and other embodiments of this invention are disclosed in an absence of hydraulic lines between these embodiments and a drilling rig. It is a significant benefit of this invention that hydraulic lines between the rig and downhole assemblies may be omitted. It may be appreciated by one skilled in the art that hydraulic lines may alternatively be provided for various uses or applications, including the disclosed assemblies or embodiments, or with other components or assemblies employed in conjunction with these embodiments. For example, an application for concurrently employing hydraulic lines in conjunction with employment of one or more of the disclosed assemblies may be elected in a shallow water installation, or to provide additional manipulating force to a riser valve sealing member to shear drill pipe. Hydraulic lines are not intended for preclusion from use, however, the disclosed embodiments may provide a more attractive alternative which permits excluding hydraulic lines.
[0192] It may be appreciated that various changes to the details of the illustrated embodiments, methods and systems disclosed herein may be made without departing from the spirit of the invention. While preferred embodiments of the present invention have been described and illustrated in detail, it is apparent that still further modifications and adaptations of the preferred and alternative embodiments will occur to those skilled in the art. However, it is to be expressly understood that such modifications and adaptations are within the spirit and scope of the present invention, which is set forth in the following claims. | A subsea riser disconnect assembly 10 may be actuated from a drilling rig DR by axial movement of an upper riser 35 relative to a lower riser 28 , for disconnecting the upper riser 35 from the lower riser 28 . A subsea riser valve assembly 20 may be actuated from the drilling rig DR by axial movement of the upper riser 35 relative to the lower riser 28 , for sealing an interior portion of the lower riser 28 and well bore WB below the subsea riser valve assembly 20 . A drill pipe disconnect 30 may be actuated from a drilling rig DR, either onshore or offshore, for disconnecting an upper portion of drill pipe 236 from a lower portion of drill pipe 240 . The drill pipe disconnect 30 may be actuatable by hydraulic and/or mechanical forces applied to the drill pipe disconnect 30 from the drilling rig DR. The drill pipe disconnect 30 may be compatible for use with or without the subsea riser disconnect assembly 10 and/or the subsea riser valve assembly 20 . The component assemblies of this invention may improve the efficiency and lower the cost of recovering hydrocarbons by reducing drilling costs and time requirements. Also, the ability to relatively quickly disconnect a floating rig from a well may enhance the safety of persons and equipment facing hostile weather conditions or other emergency situations. | 4 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The invention relates to a wrist watch having a glass rim.
[0003] 2. Description of the Prior Art
[0004] With conventional wrist watches, it has been general in wrist watches, in which a movement is inserted or taken out on a side of a glass rim, to fix the glass rim by means of machine screws.
[0005] [0005]FIG. 3 is a view illustrating a construction of a conventional wrist watch, in which a glass rim is fixed by means of machine screws. In the construction of a conventional wrist watch, a female thread portion 21 a is provided on an outer periphery of a water-proof packing 40 interposed between a glass rim 21 and a barrel 31 . Accordingly, a configurational dimension from a dial-plate parting diameter D 1 an outward form of to the glass rim 21 is the sum of a dial plate bearing surface width A, a width D of a wall, to which the water-proof packing 40 is mounted, a width B of a box for the water-proof packing 40 , a wall thickness C of the box, a dimension E of the female thread portion, and a width F of bearing surfaces of the glass rim 21 and the barrel 31 , that is, (A+D+B+C+E).
[0006] [0006]FIG. 6 is a cross sectional view showing a construction for fixation of a chamfer-type glass rim in a conventional wrist watch. A glass rim 22 has a chamfer portion 22 a with an interference between it and a barrel 32 , and is fixed to the barrel 32 by the interference. Accordingly, stress at the time of mounting is applied to fixed portions of the glass rim 22 and a glass 70 to make the same susceptible of deformation, so that the adhesive structure of the glass 70 to the glass rim 22 cannot be used due to deterioration in adhesive quality and so the glass 70 is fixed to the glass rim 22 through a plastic packing 70 a having a chamfer. Also, since the glass rim 22 and the barrel 32 are fixed to each other by means of the chamfer portion 22 a , they are restricted to a round configuration in plan, and are used under such design restrictions that in view of maintenance of the quality of fixing of the glass rim 22 , the glass rim 22 is formed from a material except a precious metal or increased as a whole in wall thickness.
[0007] Conventional wrist watches causes a problem that since machine screws are arranged on an outer periphery of a water-proof packing in order to maintain water-proofness for a barrel of a watch casing and a glass rim, a width from an external shape of a glass portion of the glass rim to an external shape of the glass rim is enlarged, and so it is difficult to make the glass rim thin. Therefore, although a design quality is demanded, it has been difficult under considerable design restrictions to seek after a design.
[0008] Also, wrist watches, in which a glass rim is fixed by mounting a portion of the glass rim directly to a barrel of a watch casing with a chamfer, cause a problem that in order to maintain the quality of opening and closing the glass rim, the glass rim is required to have a width and thickness for ensuring the strength of a glass rim material. Further, with wristwatches intended for accessories and ornaments, a precious metal material is frequently used to make a glass rim but a usable material is limited due to the material strength and dimensional restrictions, thus causing a problem that a material is restricted. Therefore, for preservation of strength, the glass rim must be made considerable in thickness and width, so that it is not possible to make the glass rim thin and to make a thin-type wrist watch, which is wanted by users, and development of design quality is sought after with difficulty.
[0009] Under these circumstances, with a chamfer-type glass rim, stress at the time of mounting possibly leads to coming-off of an adhesive portion in quality in the case where a glass is fixed to the glass rim by an adhesive, so that such way of fixation is less implemented and is made little use of. Also, at the time of maintenance of a movement with hands and a dial plate, opening and closing of the glass rim entails degradation in quality of mounting, and so the way of fixation is not accepted in the market.
SUMMARY OF THE INVENTION
[0010] Thereupon, the invention has been devised in view of the above, and has its object to provide a wrist watch, in which a glass rim is reduced in width and in thickness, restrictions on materials for the glass rim are relaxed, and a glass rim of a high design quality having a demand in the market is fixed.
[0011] The invention provides a wrist watch comprising a glass rim for fixation of a glass; a barrel, which contacts with an underside of the glass rim to contain therein a movement; a first packing provided between the glass rim and the barrel to ensure water-proofness between the glass rim and the barrel; and screws disposed inside of the packing to fix the barrel and the glass rim together.
[0012] The screws are disposed inside of the first packing-whereby it is possible to provide a glass rim of a small diameter while ensuring water-proofness.
[0013] Also, according to the invention, the screws have a second packing in an optional position on an external shape thereof.
[0014] The second packing is provided on the screws to enable providing a glass rim of a small diameter.
[0015] Also, with the wrist watch according to the invention, the barrel has screw recesses, into which the screws are inserted, and the second packings and the screw recesses engage with each other.
[0016] The screw hole and the second packing engage with each other to thereby enable ensuring water-proofness on the screw hole.
[0017] Further, with the wrist watch, the glass rim comprises a dial-plate bearing surface, which bears a dial-plate, a female thread portion adapted to engage with the screws, a packing box, which bears the first packing, and a bearing surface, which bears the barrel.
[0018] Thereby, it is possible to reduce a width of the glass rim.
[0019] Also, in the construction composed of a glass rim, a barrel and a back cover, the screws not only latch the glass rim but also may be used for fixation of the back cover as well as latching of the glass rim.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0020] A preferred form of the present invention is illustrated in the accompanying drawings in which:
[0021] [0021]FIG. 1 is a cross sectional view showing a wrist watch according to an embodiment of the invention;
[0022] [0022]FIG. 2 is a side view showing a machine screw for fixation of a glass rim in a wrist watch according to an embodiment of the invention;
[0023] [0023]FIG. 3 is a view illustrating a conventional construction for mounting of a glass rim;
[0024] [0024]FIG. 4 is a view illustrating the construction for mounting of a glass rim according to an embodiment of the invention;
[0025] [0025]FIG. 5 is a cross sectional view showing another example of a construction, in which a glass rim is mounted, according to an embodiment of the invention; and
[0026] [0026]FIG. 6 is a cross sectional view showing another example of a construction for mounting of a glass rim in a conventional configuration.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0027] The invention will be described below in detail with reference to the drawings. In addition, the invention is not limited to embodiments.
[0028] [0028]FIG. 1 is a cross sectional view showing a wrist watch as assembled according to an embodiment of the invention. A movement 10 with hands and a dial plate is assembled into a barrel 30 from a side of a glass rim 20 with a movement holding member such as an inner frame 15 , and a packing 40 intended for water-proofness between the glass rim 20 and the barrel 30 is wound around a wall of an outer periphery of a female thread portion 21 a provided on the glass rim 20 to engage with a packing box of the barrel 30 and machine screws 50 cause the packing 40 to be engaged by the female thread portion 21 a , which is provided on the glass rim 20 , from a back side of the barrel 30 with the barrel 30 therebetween to be fixed.
[0029] [0029]FIG. 2 is a side view showing a machine screw 50 for fixation of the glass rim 20 . The male screw 50 has a packing 50 a adapted to engage in an optional position between a male screw recess 30 a provided in the barrel 30 and the male screw, the packing having an interference for water-proofness.
[0030] Hereafter, the construction of fixing the glass rim 20 in such a wrist watch will be described in order.
[0031] [0031]FIG. 4 is a view illustrating the construction of a wrist watch according to the invention. The view is a cross sectional view representing the constitution from a dial-plate parting diameter D 1 to an external shape of the glass rim 20 . A configurational dimension from a dial-plate parting diameter D 1 to the glass rim 20 is (A+E+B+F), wherein a dial-plate bearing surface width is A, a dimension of the female thread portion is E, a width of a box for the water-proof packing 40 is B, and a width of bearing surfaces of the glass rim 20 and the barrel 30 .
[0032] Accordingly, unlike a conventional wrist watch, the sum of a width D of a wall, to which the water-proof packing 40 is mounted, and a thickness C of a wall constituting a configuration of the box, that is, (D+C) is not necessary, so that it is possible to reduce an edge width of the glass rim 20 by (D+C). Generally, the width D of a wall, to which the water-proof packing 40 is mounted, can be reduced by from around 0.5 mm to 0.6 mm, and the thickness C of a wall constituting a configuration of the box can be reduced by from around 0.3 mm to 0.6 mm. Accordingly, (D+C) is decreased by from around 0.8 mm to 1.1 mm on one side. The entire external shape can be decreased by 1.6 mm to 2.2 mm, a value, which is twice the above value, on both sides.
[0033] [0033]FIG. 5 is a cross sectional view showing another example 1 of a construction, in which a glass rim is mounted, according to an embodiment of the invention. A glass rim 20 of a wrist watch according to the another example 1 is fixed by fixing a movement 10 with hands and a dial plate into a barrel 30 through an inner frame 15 from a direction, in which the glass rim 20 is assembled into the barrel 30 , assembling the glass rim in a state, in which a water-proof packing 40 is wound around an outer wall of a female thread portion 21 a of the glass rim 20 , and turning machine screws 50 provided with a packing 50 a and intended for maintaining water-proofness between the screw and a male screw recess 30 a , through a back cover 60 provided for easiness of maintenance and an increase in variations of external appearance and arranged on a back surface side of the barrel 30 .
[0034] Also, water-proofness between the barrel 30 and the back cover 60 is maintained by a water-proof packing disposed inside of the machine screws 50 provided with the packing and assembled on a side of the barrel 30 .
[0035] As described above, since it is possible in a wrist watch of the invention to readily reduce a width of a glass rim as compared with a conventional construction, it is possible to enlarge a display portion of a dial plate by such reduction and to improve visibility of the display portion. Also, since the glass rim is fixed by machine screws, it is possible to use a material of relatively low strength such as precious metals for the glass rim. Since there is no configurational restriction in terms of construction as exemplified by circular and varied configurations in plan, there can be obtained an effect that wrist watches of different designs suited to a user's taste can be readily presented by gathering designs for the glass rim in abundance. | To provide a wrist watch having a small rim width while ensuring the strength of a glass rim. A movement with hands and a dial plate is assembled into a barrel from a side of a glass rim. A water-proof packing is arranged between a glass rim and the barrel. Machine screws are mounted inside the water-proof packing to fix the barrel and the glass rim together. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is the United States national phase under 35 U.S.C. §371 of PCT International Patent Application No. PCT/EP2009/007707, filed on Oct. 27, 2009, and claiming priority to European Application No. 08018760.2 filed on Oct. 27, 2008, and German Application No. 10 2008 053 409.9, filed on Oct. 27, 2008.
BACKGROUND OF THE INVENTION
1. Field of the Invention
Embodiments of the invention relate to a method for making security mechanisms available in wireless mesh networks.
2. Background of the Related Art
A wireless network is a network in which data are transmitted according to the Wireless Local Area Network (WLAN) standard. Equally valid access points are used in the IEEE 802.11 WLAN standard family. Depending on the network configuration, some of them allow a transfer to a backbone network. One access point and the stations to which it transmits form a wireless cell. Most WLAN installations are operated in infrastructure mode, wherein the stations in a wireless cell can communicate with other stations, or with devices reachable through the backbone network, only through the access point. The individual wireless cells are linked to each other by the backbone network, creating an overlapping WLAN. Until now, backbone networks have primarily been cabled networks, typically an Ethernet LAN.
The upcoming IEEE 802.11s standard is an expansion, with which wireless cells will no longer need the backbone network in the cable network. The result of this is a mesh WLAN, in which the connection between access points is now also wireless and fully transparent for the stations. The mesh network operates as a self-organizing network, building itself dynamically from the participating nodes. Each participating node also functions as a router, using the routing protocol, and forwards the data traffic on to other nodes. Unlike the single-hop communication used by IEEE 802.11 WLANs, IEEE 802.11s mesh WLANs use routing mechanisms on the MAC layer to permit multi-hop communication.
When WLANs are used in businesses, these networks must be secured by encryption measures. In addition to authentication, security against eavesdropping and invasion is an important requirement. In the IEEE Standards for Information Technology—Telecommunications and Information Exchange Between Systems—Local and Metropolitan Area Networks—Specific Requirements—Part 11: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) Specifications: Amendment 6: Medium Access Control (MAC) Security Enhancements, 2004 it is stated that the IEEE 802.11i standard defines some new WLAN Security Mechanisms and introduces the Robust Secure Network (RSN) protocol for establishing a secure connection with an Access Point. RSN is used for resistance against external attacks such as eavesdropping, data alteration, and data insertion, and provides effective access control as well as cryptographic data protection.
The use of group keys in IEEE 802.11i, with which data traffic between nodes is secured against eavesdropping by encrypting it, wherein a group key is used for communication with multiple other nodes, cannot guarantee sufficient protection against data alteration or interception by other subscribers on the network, i.e., internal attackers, because of the multi-hop data forwarding. If we also consider possible attacks at the routing level, such as intentional disruption of data traffic or retargeting of routing paths by other subscribers on the mesh network, it is clear that even using different keys in pairs is not enough, and the existing mechanisms are either too complex, extremely expensive, or inadequate for the protection needed in mesh networks.
A suggestion for implementing a currency system in order to promote cooperation, especially for forwarding foreign data packets, is included in Levente Buttyán, Jean-Pierre Hubaux. Nuglets: a Virtual Currency to Stimulate Cooperation in Self-Organized Mobile Ad Hoc Networks, 2001, and is intended to prevent network subscribers from behaving selfishly, i.e., intentionally intercepting packets that are supposed to be forwarded onward and thereby disrupting or even completely preventing communication between other subscribers. It rewards correct forwarding of foreign traffic by then allowing one's own traffic to be sent over the network. However, such a solution is difficult to implement in mesh networks, due to the varying availability of nodes, and requires an extremely high expense when a fair cost model is calculated.
An older method for protecting networks against external attacks is Wired Equivalent Privacy (WEP). However, WEP has a lot of security gaps and is therefore no longer used. In 802.11i and previously, these problems are not even mentioned, since attacks by selectively disrupting packets to be forwarded, as well as the use of multi-hop environments, had not yet been considered.
Security mechanisms at management level, described in Draft Standard for Information Technology—Telecommunications and Information Exchange Between Systems—Local and Metropolitan Area Networks—Specific Requirements—Part 11: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) Specifications: Amendment: Protected Management Frames, D1.0, 2006, and also at routing level, such as Secure OLSR, described in Thomas Clausen, Emmanuel Baccelli, Securing OLSR Problem Statement, LIX, Ecole Polytechnique, 2005, or SAODV, described in Manel Guerrero Zapata, Secure Ad hoc On-Demand Distance Vector (SAODV) Routing, Technical University of Catalonia (UPC), 2005, for protection of routing protocols, assume an existing key distribution and administration system and also cannot prevent other manipulations and attacks by legitimate network subscribers.
BRIEF SUMMARY OF THE INVENTION
We provide the methods and arrangements for making security mechanisms available in wireless mesh networks that provide increased security in wireless mesh networks in keeping with the current state of the art.
To increase security in wireless mesh networks, embodiments use differentiated confidence levels defined by a Type of Protection or ToP. Embodiments may encompass both the mechanism by which data packets are marked with a ToP value and the fact that the ToP value is transported in the mesh network such that each participating node in the mesh network receives at least one assigned ToP value. In the mesh network nodes, for each incoming data packet, it is then determined whether the ToP values of the node match the ToP value of the data packet. The node also tests to see whether the target or recipient address of the MAC layer (L2) corresponds to its own address. The routing mechanisms are therefore enhanced by the use of ToP values. If this ToP value combination is allowed in the node, the data packet can be processed by that node and forwarded on to another node with a corresponding ToP value. If this ToP value combination is not allowed in the node, then the data packet cannot be processed by that node and cannot be forwarded on to another node with a corresponding ToP value. Data traffic routing is controlled by means of this differentiation, and the incidence of attacks such as selective forwarding is thereby reduced.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 shows mesh nodes with different confidence levels and an authentication server,
FIG. 2 shows the format of a mesh data packet according to the IEEE 802.11s standard,
FIG. 3 shows the format of the expanded mesh header with ToP field,
FIG. 4 shows the fully classified confidence levels in a residential environment,
FIG. 5 shows the partially classified confidence levels in a business environment,
FIG. 6 shows the unclassified confidence levels in a business environment, and
FIG. 7 shows multi-hop authentication in a mesh network.
LIST OF REFERENCE NUMBERS
A-G Nodes
H Authentication server
N 1 Nodes with the Visitor ToP
N 2 Nodes with the Employee ToP
N 3 Nodes with the Employee ToP and additionally the Visitor ToP
T 1 Authentication
T 2 Data traffic with the Visitor ToP
T 3 Data traffic with the Employee ToP
DETAILED DESCRIPTION OF THE INVENTION
Confidence level differentiation cannot prevent malicious internal nodes within those same confidence levels from carrying out successful attacks, but by differentiating between confidence levels, the number of possible malicious internal nodes is reduced to a minimum, and internal nodes are prevented from carrying out successful attacks outside of their confidence level.
The Mesh Flags field in the mesh header of a data packet, available per standard IEEE 802.11s, is used according to the invention to define an additional ToP flag. This ToP flag indicates that the Mesh ToP field, with a size of one octet, follows the Mesh Address Extension field. This Mesh ToP field is introduced according to the invention and is used to store the ToP value of the data packet. Anchoring the ToP value in the mesh header for transport in the IEEE 802.11s mesh network makes it possible for the ToP value of the data packet to be read by all nodes in between so that the correct forwarding decisions can be made.
In another solution, the ToP value can be transported in an additional header inserted above or below the MAC header.
With the multi-hop communication on the MAC layer, the 4-address frame format is used for the mesh frame, wherein the ToDS and FromDS flags are set at a value of 1 in the Frame Control field. This guarantees that only mesh-enabled nodes will process the additional mesh header at the beginning of the body frame with user data located in it. Legacy nodes according to the IEEE 802.11 standard, which do not possess the necessary capabilities for mesh networks and the expansions, simply recognize an invalid ToDS/FromDS combination and reject the data packet.
The ToP value can be set depending on information from the application layer of the subscriber or the network layer in the node. One solution consists of using ToP values such as VLAN tags and assigning different ToP confidence levels to different IP address areas. The ToP is inserted in the data packet by a routing function in the originating node, for example, and is transparent for the application. In another solution, the application for a subscriber it itself capable of selecting the corresponding ToP value and inserting it in the data packet. In a further solution, the value of the IP Type of Service field can be considered by means of a network function in the originating node.
In each node, a forwarding table is inserted for each associated ToP value and lists the ToP values of the nodes that can be trusted. This reveals the confidence relationships between nodes and allows for the corresponding routing.
For data packet routing in the mesh network, a Path Selection Protocol is defined that uses the ToP values from the forwarding tables and their confidence relationships.
An authentication server, which can be reached from the network and is approved for initial authentication of the network-compatible nodes, assigns one or more confidence levels to each participating node, which are represented by one or more ToP values stored in the forwarding tables. For the various ToP values of the nodes, various traffic classes are defined in the network at the same time and used to separate the data traffic by means of the Path Selection Protocol.
The ToP value transported in a data packet on the mesh network is read by the participating nodes and forwarded to a node with an associated ToP value that corresponds to that of the first node. This allocation of data packet ToPs to participating nodes makes separation of data traffic and routing to various confidence levels possible and prevents selective forwarding of data packets.
Introducing confidence level differentiation in mesh networks also requires an appropriate metric. Very fine-grained splitting into different ToPs makes the network fragile, i.e., the data packets are forwarded only via nodes with the same ToPs, which makes the number of possible routes very small or partitions the network. The invention therefore proposes the use of hierarchical ToP mapping. With hierarchical arrangement of the confidence levels, a load comparison can be made and partitioning of the network can be avoided.
In a ToP mapping system with fully classified confidence levels, packets with a low confidence level can be processed by every node in the mesh network, because the nodes with a higher confidence level also include the lower confidence levels.
In a ToP mapping system with partially classified confidence levels, partial confidence level areas for the nodes are fully classified, so that the packets in these areas are processed as described above. However, packets with the corresponding confidence level cannot be exchanged between different areas with the same confidence level values.
In a ToP mapping system with unclassified confidence levels, packets with the corresponding confidence level can be exchanged between two nodes with the same confidence level values, but packets with a lower confidence level cannot.
In addition to the ToPs, after authentication each node receives the associated IEEE 802.11i group key from the authentication server. This key is transmitted by means of a Pairwise Master Key (PMK) that is sent from the authentication server to the authenticating node. The PMK is generated during authentication. Then the node is ready to participate in the MAC Layer Routing Protocol.
For transporting the ToP field, the invention provides for at least one type of integrity protection for the ToP field, for increased security. If the integrity of the ToP field is not secured, new attacks can occur. For example, an attacker can lower the confidence level of a packet so that nodes with another confidence level can read, change, or reject the packet. In addition, such a classification attack can be used to carry out Denial-of-Service attacks on specific nodes or parts of the mesh network. If, for example, a certain ToP value supports only one path through the mesh network and all data traffic is set to this ToP value, that path would quickly be overloaded. This would mean that no further communication on that path, and therefore for that ToP value, would be possible.
Integrity is achieved by using the appropriate ToP group key. This guarantees that nodes which do not have this ToP group key cannot modify the ToP field without damaging the integrity of the packet.
Because some mesh header fields are modified during forwarding, so that their signatures are not valid for integrity protection, variable fields must not be used for generating signatures. Integrity protection for these fields is not provided in that case, or the receiver tries to predict the value of the variable fields, which is often easy to do.
Preferably, the invention provides for the trusted data traffic also to be encrypted using the group key, because due to the characteristics of the wireless transport medium, every node is capable of intercepting the data traffic or inserting its own data traffic. Distribution of the group key per ToP and the use of encryption guarantee that only nodes that have the correct group key can read the packet contents. Interception of trusted data is therefore prevented, which is very important in business environments where visitors can use the WLAN mesh like employees.
In the IEEE Computer Society, IEEE Standard for Local and Metropolitan Area Networks, Specific Requirements, Part 11: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) Specifications, June 2007, the Robust Secure Network (RSN) protocol is described, which is used for secure communication in an IEEE 802.11 network. RSN normally protects only frames that are exchanged between the station and the access point, but the multi-hop case is not described in the IEEE 802.11 standard.
The invention proposes to expand the RSN concept to multi-hop mesh networks. This involves a change to the mechanism for key distribution as well as authentication, which in particular guarantees protection of point-to-point communication. In this way, a supplicant, which is a newly added node, in order to access the network resources, must be authenticated on the network. Authentication is done by the authenticator, typically an access point in infrastructure mode, which tests the supplicant's authenticity using an authentication server and grants or refuses access to the services requested through the authenticator. A ToP value is assigned at this point.
Authentication between the supplicant and the authentication server can be based on a group key or can be per IEEE 802.1x, as stated in IEEE Computer Society, IEEE Standard for Local and Metropolitan Area Networks, Port-Based Network Access Control, December 2004, and in the Extensible Authentication Protocol (EAP), as described in B. Aboba, L Blunk, J. Vollbrecht, J. Carlson, and H. Levkowetz, Extensible Authentication Protocol (EAP), IETF, RFC 3748, June 2004. Communication between the authenticator and the authentication server is then possible using a Backend Protocol such as RADIUS, described in C. Rigney, S. Willens, A. Rubens, and W. Simpson, Remote Authentication Dial In User Service (RADIUS), IETF, RFC 2865, June 2000, and secured using a group key between the authenticator and the authentication server. It is mandatory that the supplicant and the authenticator, as well as the authenticator and the authentication server, must not be connected directly to each other, but they can communicate with each other via multiple hops using the mesh network.
Preferably, a new mesh node can be authenticated on an existing mesh network, in which a special node, such as the mesh portal point, is chosen as the authenticator.
FIG. 1 shows an arrangement of 7 mesh nodes A, B, . . . G and an authentication server H such as would be found in a small business environment. Node A is a mesh access point that offers a connection to the authentication server or to other networks, e.g., to other mesh networks or directly to the Internet. The other nodes are mesh points or mesh access points. All mesh nodes participate in the MAC layer routing protocol that is used in this particular mesh network. WLAN stations, which are connected to a mesh access point and integrated transparently into the mesh network, are not represented in this figure.
Three confidence levels are defined in this figure and shown as Visitor ToP N 1 and Employee ToP N 2 or the combination of both N 3 . Nodes B and F with Visitor ToP N 1 are allowed to participate on the mesh network only temporarily and do not belong to the business, so they are assigned a different ToP from that of node G with Employee ToP N 2 . If each node can be assigned only one ToP, then the network is split up into multiple networks with different confidence levels. This leads to network coverage difficulties and nodes that are likely to be unreachable. Therefore, the assignment of multiple ToPs to one node is permitted, and it allows data packets to be forwarded to nodes with a different ToP. FIG. 1 includes nodes A, C, D, and E with the combined ToP N 3 for Employee ToP and also Visitor ToP. This guarantees that these nodes A, C, D, and E can forward all of the data traffic on the mesh network.
The process of authenticating a participating node with authentication server H is indicated by the reference designation T 1 , wherein after authentication, each node receives its ToP value and the associated group key. Data traffic with the confidence level of a visitor, which contains the Visitor ToP value in the ToP field of the mesh header, is indicated by the reference designation T 2 . Data traffic with the confidence level of an employee, which contains the Employee ToP value in the ToP field of the mesh header, is indicated by the reference designation T 3 . Data packets with both confidence levels, Visitor ToP and Employee ToP, are forwarded between nodes A, C, D, and E.
Mesh nodes for which a lower power consumption is desired can preferably reduce their wireless operation by forwarding only data packets with their own confidence level, as illustrated for node G in FIG. 1 .
FIG. 2 shows the format of a mesh data packet in mesh networks corresponding to standard IEEE 802.11s. Data can either be sent exclusively within a mesh network or can go beyond the limits of the mesh network. The IEEE 802.11 MAC header of a mesh data packet allows for 4 addresses and one additional mesh header, in order to direct the packet through multiple hops to its destination. The mesh header contains the Mesh Sequence Number field, which contains a point-to-point sequence number in order to recognize duplicate and out-of-order frames. If the mesh network interacts with nodes that do not belong to the mesh, it is possible to attach additional addresses in the Mesh Address Extension field by setting the Address Extension Flag in the Mesh Flags field.
FIG. 3 shows the format of the expanded mesh header. According to the invention, the mesh header described in the IEEE 802.11s standard is expanded to include the Mesh ToP field, which is inserted after the Mesh Address Extension field. An additional ToP flag is defined in the Mesh Flag field and indicates whether or not this Mesh ToP field is contained in the mesh header.
FIG. 4 shows an example of two fully classified confidence levels in a residential environment. The data traffic designated as ToP Resident is only forwarded to nodes with the Resident confidence level. If security is ensured by encrypting, then this traffic cannot be read by a node with the Visitor ToP. Packets secured with the Visitor ToP can be forwarded and read by every node in the mesh network, because due to the complete classification of the confidence level hierarchy, every node with the Resident ToP also receives the Visitor ToP. This makes resident nodes more trusted than visitor nodes.
FIG. 5 shows an example of multiple partially classified confidence levels, as they could be used in large business mesh networks for a company. The nodes with the Visitor ToP are the least trusted. The nodes with the Employee ToP are divided into various departments of the company. Departments 1 and 2 are fully classified; Department 3 has no connection to the others. In this figure, the company's internal traffic must be protected with at least the Employee ToP. If security is required for the traffic in Department 1 , then its ToP must be used; otherwise the employees in Department 3 would also be able to read traffic transmitted with the Employee ToP. Data traffic designated with the Visitor ToP can be forwarded by every node that is participating on the mesh network. However, nodes with the Visitor ToP are able to read and forward only traffic that is protected with the Visitor ToP.
FIG. 6 shows an example of unclassified confidence levels in a business environment. Here traffic with the Department 1 ToP can be forwarded by nodes with the Department 2 confidence level and vice versa. However, packets with the Visitor ToP designation are forwarded only by nodes with the Visitor ToP and nodes with the Department 2 ToP. Such an arrangement can be necessary, for example, in order to protect the resources of nodes with the Department 1 ToP.
FIG. 7 shows multi-hop authentication in a mesh network. For authentication of supplicants, a secure connection is made with the authenticator, which tests the supplicant's authenticity with the authentication server. Authentication between the supplicant and the authentication server takes place in a secure tunnel based on a group key or through IEEE 802.1x and the EAP protocol. Communication between the authenticator and the authentication server is accomplished via a Backend protocol such as the RADIUS protocol and secured by a group key between authenticator and authentication server. Communication can thus involve multiple hops in the mesh network. | A method for making safety mechanisms available in wireless mesh networks which have a plurality of nodes that are interconnected by multi-hop communication in a wireless network meshed by mesh routing in the MAC layer, every node being active as a router to forward the data traffic of the other nodes. At least two differentiated levels of confidence are defined by a type of protection (ToP) the value of which represents a specific level of confidence for the nodes and data packets, the data packets being labeled with a ToP value in the mesh header, and at least one ToP value being allocated to the participating nodes, the nodes forwarding the data packet in the mesh network using the ToP values of the node and of the data packet if this ToP value combination is admissible in the node. | 7 |
BACKGROUND OF THE INVENTION
The present invention relates generally to roadway construction and more particularly to techniques for avoiding crumbling or deterioration of the structural edges of a roadway joint assembly. More specifically, the invention is especially adaptable for use in roadway structures wherein joint assemblies having resilient characteristics are utilized.
As is generally known, one of the most troublesome problems related to concrete structures upon which vehicular traffic must pass is the wear and deterioration that occurs to the edges of pavement or similar material, particularly at joints which must be formed between two adjacent concrete walls or slabs which form the roadway structure.
In order to overcome problems of this type, many attempts have been made to provide protective devices for different parts of the roadway. Such protective devices may involve, for example, angular iron members, steel ribs and the like.
However, all of the metallic protectors which are in use today give rise to great inconvenience for several reasons. First of all, it is relatively difficult to achieve a good metal-to-concrete connection primarily due to the rather difficult conditions created by different thermal expansion coefficients. As a result, the attachment of such metallic protectors will generally be accomplished by the utilization of anchorage devices which must be imbedded into the concrete and which must be welded to metallic protective members.
As will be evident, significant stresses will arise in roadway structures whereby different parts of the roadway will move relative to other parts because of the different stresses and because of varying thermal characteristics. The stresses which occur because of traffic load will usually be concentrated at the metallic anchorage devices thereby causing them to become loosened after a relatively short period of time. This and other problems which arise in structures of this type will require frequent road maintenance procedures.
The present invention is directed toward providing an improved protective system for roadbed joints of the type described above. The advantage of the present invention resides in the fact that continuous structural protection may be built-in at the edge of the concrete slab of the roadway without requiring utilization of metallic anchorages. Protection of the type afforded by the present invention enables high performance anti-abrasive edge structures to be provided which may be totally bonded to the concrete of the roadway slab and which will present a thermal expansion coefficient equivalent to the thermal expansion coefficient of the concrete itself.
Of particular importance is the fact that the arrangement of the present invention permits the utilization of flexible joints, especially a joint of a particular type which gives rise to significant advantage.
The significant advantages of the invention involve the fact that the roadway joints utilizing the invention may be built at any time after the pouring of the concrete without depending upon accurate positioning of metallic protectors or anchors. The joint may be totally or partially repaired without destroying the nearby concrete and it will provide a continuous non-skid surface. The arrangement of the invention provides a joint which is totally capable of resisting oxidation, water penetration and which is also resistant to most solvents and chemicals. The invention permits the equal distribution of load of traffic over the joint system while avoiding stress concentration.
SUMMARY OF THE INVENTION
Briefly, the present invention may be described as an improvement in a roadway structure formed of concrete slabs interconnected by a joint formed between a pair of opposed walls of said slabs, said walls defining therebetween a gap which is bridged by said joint, the improvement of the invention particularly comprising shoulder portions defining at least the upper adjacent edges of said opposed walls of said slabs, said shoulder portions consisting essentially of cured silica-epoxy mortar built into the walls of the slabs by compacting the silica-epoxy mortar into previously prepared sockets formed in the walls to provide structurally bonded reinforcement at the shoulder portion. A resilient joint interposed between the opposed walls may extend in adhesive bonding engagement at least along the portions of the walls defined by the shoulder portions of the present invention.
In the preparation of the joint of the invention, at the time that concrete is poured, a socket may be provided at the edges of the slabs which form the walls to be connected by the joint, the socket being formed by sawing the already existing concrete structure. The socket may then receive the silica-epoxy mortar which is compacted by means of a compacter device to the level of the pavement. Thereafter, the silica-epoxy mortar may be allowed to harden which will occur in a few hours thereby enabling the structure to be ready for use.
If necessary, the socket which is formed in the concrete shoulders of the slabs may be previously primed with an appropriate adhesive to improve the bonding qualities between the mortar and the concrete.
The device of the present invention is particularly suitable for use with a sealing system wherein a resilient joint is formed between the opposed walls of the slabs. The joint with which the present invention is used may particularly comprise a sealing element consisting essentially of resilient material and formed to define cavity means internally thereof. An adhesive material is applied between the sealing element and each of the opposed walls of the slabs in order to effect an adhesive bond therebetween, the adhesive material being capable of setting after application thereof in order to effect the adhesive bond. A filler material is then introduced into the cavity means of the sealing element under pressure and the filler material is rendered rigid after introduction into the cavity means. The sealing element is capable of undergoing flexure as the result of introduction into the cavity means of the pressurized filler material thereby to maintain the adhesive bond pressed between the sealing element and the opposed walls during setting of the adhesive material. The filler material and the adhesive material are selected such that the adhesive material sets to form the adhesive bond in the joint prior to hardening of the filler material within the cavity means.
By combining a joint system of this type with the silicon-epoxy mortar shoulder portions of the invention, a particularly long lasting, durable and effective joint system may be formed between slabs of a roadway structure.
The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its use, reference should be had to the accompanying drawings and descriptive matter in which there is illustrated and described a preferred embodiment of the invention.
DESCRIPTION OF THE DRAWINGS
In the drawings:
FIGS. 1-4 are, respectively, cross sectional views showing the structure of the present invention in different stages of formation thereof; and
FIG. 5 is a perspective view showing a finished joint system utilizing the shoulder structure of the invention and a resilient joint system.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring first to FIG. 1, there is shown an example of a site where a seal or joinder must be formed between a pair of opposed walls. In FIG. 1, there are shown walls 10 and 12 which may represent the terminations of two sections 14 and 16 of a pair of slabs of a roadway, which slabs are to be joined together. Since roadways of the type to which the present invention relates are not normally formed in continuous, unbroken concrete sections, gaps such as that between the walls 10 and 12 will exist between sections of the roadway. Accordingly, it becomes necessary to seal or otherwise join together the walls 10 and 12 so that there will be formed a unitary structure which will, nevertheless, be capable of absorbing relative movements between the walls 10 and 12 which may occur during stressing or loading of the roadway.
A seal of the type contemplated for use with the present invention is shown in FIG. 5 wherein the structure in accordance with the invention is depicted in its finished form. As will be noted from FIG. 5, a sealing element 20 which essentially comprises a longitudinal member of resilient material is interposed between the walls 10 and 12. The present invention is particularly concerned with the shoulder portions 100 and 120 which are formed adjacent the resilient joint formed by the sealing member 20.
As will be noted from FIG. 5, the basic slabs 14, 16 which form the roadway are made from concrete. If the portions occupied by the shoulders 100 and 120 are permitted to be composed of concrete material, then severe problems could develop because of chipping, breakage or wear of the portions adjacent the resilient joint. Since the slabs forming the roadway will be particularly susceptible to damage at these areas, it is important that these areas be reinforced so that the joint system which is formed will be long-lasting and durable.
By the present invention, the portions of the concrete slabs which occupy the edges of the slabs adjacent the resilient joint, are removed by sawing or by some similar procedure, thereby to form sockets 11 at the upper edge portions of the walls 10 and 12 of the concrete slabs 14 and 16. After the sockets 11 have been formed, a sizing board 15 having a width equivalent to a gap 13 existing between the walls 10 and 12 is placed in position between the walls 10 and 12, the sizing board 15 extending upwardly beyond the upper terminations of the slabs 14 and 16. Subsequently, silica-epoxy mortar material 41 is introduced into each of the sockets 11 on either side of the sizing board 15.
After the mortar 41 has been placed in position, a compacter 6 is applied to the mortar material 41, as best seen in FIG. 3. The mortar material 41 is compacted down to the upper level of the slabs 14 and 16 in order to form the shoulder portions 100, 120, as seen in FIG. 4, wherein the finished shoulder portions are depicted prior to introduction of the sealing joint. The sizing board 15 may then be removed and a smooth gap will exist between the walls 10 and 12 within which a resilient sealing member may be provided. Furthermore, the shoulder portions 100, 120 will be smooth and continuous with the upper surface of the slabs 14, 16.
After the silica-epoxy mortar material 41 has been compacted and formed into the proper shape, it may be permitted to cure whereby the protective shoulders 100, 120 will be formed. Of course, an appropriate curing time should be permitted to elapse whereupon the seal between the walls 10 and 12 may be formed.
As best seen in FIG. 5, the seal of the present invention will comprise the sealing element 20 which has a longitudinal cavity formed therein within which filler material 34 may be introduced under pressure. Prior to introduction into the sealing element 20 of the filler material 34, an adhesive material 32 is applied between the sealing element 20 and the walls 10 and 12. Subsequently, the filler material 34 is introduced under pressure and the sealing element 20 is caused to flex in order to adapt its shape to the sides or walls 10 and 12 of a joint which is to be formed. It is of particular advantage if the adhesive material 32 which is selected is of the type which will set before elapse of a sufficient period of time to allow the filler material 34 to become hardened or rigid. Thus, during the period of time that the adhesive material 32 is setting, the filler material 34 remains in a relatively liquid state and under pressure within the sealing element 20 thereby maintaining the adhesive 32 under pressure until it sets.
With the finished joint arranged as shown in FIG. 5, the resilient member 20 will provide a sturdy connection between the walls 10 and 12 while allowing the walls to move relative to each other to a given degree in order thereby to permit displacements which may occur due to thermal expansion or the like without injuring or rupturing the joint. The shoulder portions 100 and 120 since they are formed of a silica-epoxy mortar which has undergone curing, will provide very sturdy and durable shoulder portions adjacent the sealing element 20 thereby greatly reducing the susceptibility to damage of the joint system and the necessity for frequent maintenance procedures.
Of course, it should be understood that, prior to filling of the sockets 11 with the silica-epoxy mortar material 41, the sockets may be previously primed with a proper adhesive to improve bonding between the mortar and the concrete.
As will be seen from the foregoing, the improvement of the present invention will provide for the edges of a concrete structure a longitudinal and transverse reinforcement which will consist of a protective shoulder which is structurally bonded to the concrete by compacting of the silica-epoxy mortar into the preformed sockets thereby achieving, after curing, a resistent edge which distributes the load of traffic and which protects the concrete edges from wear which may be caused by such traffic.
While a specific embodiment of the invention has been shown and described in detail to illustrate the application of the inventive principles, it will be understood that the invention may be embodied otherwise without departing from such principles. | A roadway joint wherein a gap between two generally parallel concrete walls of the roadway structure is bridged by a joint assembly having resilient characteristics is reinforced by a protective shoulder structure which will avoid abrasion, wear and destruction due to traffic of the concrete shoulders of the walls forming the joint by forming the adjacent edges of the shoulders from silica-epoxy mortar which is cured into suitable sockets formed in the concrete shoulders of the adjacent walls. | 4 |
The present application is a continuation-in-part of prior U.S. patent application Ser. No. 08/310,760, filed Sep. 27, 1994 now U.S. Pat. No. 5,554,418.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a method of forming a passivation film or a protection film and, in particular, to a method of forming a passivation film of SiO 2 (silicic acid anhydride) on a substrate made of a resinous material or a plastic material.
2. Description of Related Art
As a surface protection film (i.e., a passivation film) to be formed on a resinous material or a plastic material, attention has recently been paid to SiO 2 and its applications are being expanded. In addition, a passivation film of silicic acid anhydride of superior quality is desired.
As a method of forming a passivation film of SiO 2 on a substrate of a resinous material or a plastic material, there has hitherto been used a vapor deposition process, a sputtering process, or the like. However, this kind of conventional method has a disadvantage in that, when the surface of the substrate of the resinous material or the plastic material has irregularities in the form of projections and recesses, or curved surface, the adhesion of the SiO 2 film to the surface of the substrate or, in other words, the characteristics of adhesion of the SiO 2 film onto the irregularly shaped portions or step coverage is poor.
As a solution to this disadvantage, there has been used a plasma CVD (Chemical Vapor Deposition) process as a method of improving the adhesion of the SiO 2 film to the surface of the substrate or step coverage and of forming an SiO 2 film of superior quality.
In order to form the SiO 2 film on the surface of the substrate by the plasma CVD process, it is necessary to use an oxidizing gas such as O 2 , N 2 O or the like. This plasma CVD process has however the following problem. Namely, the substrate that is made of a resinous material or a plastic material is subjected to ashing by the radicals of the oxidizing gas. As a result, the surface of the substrate is roughened into a rough surface. In case the surface of the substrate has irregularities in the form of projections and recesses or is curved, its shape is remarkably or largely deformed, with the result that the SiO 2 passivation film of uniform thickness in conformity to the shape of the surface of the substrate cannot be formed.
Therefore, it has long been desired to establish a method of forming an SiO 2 passivation film of good quality on a substrate without subjecting the substrate to ashing.
SUMMARY OF THE INVENTION
In order to attain the above-described object, the present invention is a method of forming an SiO 2 passivation film on a surface of a substrate by plasma chemical vapor deposition (CVD) process in which organic oxysilane is used as a raw gas. The method comprises using, at a temperature not greater than one thermally deforming the substrate instead of a reactive gas having an ashing effect, a gas selected from the group consisting of Ar, He and NH 3 as a reactive gas which serves as an auxiliary for decomposing the raw gas, whereby ashing of the substrate by oxygen or hydrogen radicals is prevented.
The temperature not greater than one thermally deforming the substrate is about 250° C. or lower, preferably about 150° C. or lower.
The reactive gas may be added thereto one of fluorine group gases of CF 4 and NF 3 .
Namely, according to the present invention, in the plasma CVD process using organic oxysilane such as TEOS (tetraethoxysilane or tetraethyl orthosilicate: Si(OC 2 H 5 ) 4 ), a gas such as Ar, He or NH 3 is used instead of a reactive gas having an ashing effect such as an oxidizing gas of O 2 , N 2 O or the like or H 2 gas at an initial stage of film formation. By this arrangement, an SiO 2 film can be formed with good adhesion or good step coverage without ashing the surface of the resin material or plastic material which serves as the substrate.
Further, if there is added a fluorine group gas such as CF 4 , NF 3 or the like which accelerates the decomposition reaction of --CH radicals, --OH radicals or the like from the organic oxysilane to be used as the raw gas, the speed of film formation can be increased, without the surface of the substrate being subjected to ashing.
When a passivation film of SiO 2 is formed on the surface of the substrate of a resinous material or a plastic material by plasma CVD process by using organic oxysilane, if an oxidizing gas such as O 2 , N 2 O or the like is used, the film formation is carried out by decomposing the organic oxysilane mainly by oxygen radicals and further compensating the oxygen atoms which come short at the time of decomposition.
In this case, there will be present a large amount of oxygen radicals in the gaseous phase, with the result that the surface of the resinous material or the plastic material as the substrate is subjected to ashing.
The substrate is also subjected to ashing by hydrogen radicals when H 2 is used.
If one of the gases of Ar, He and NH 3 is used instead of an oxidizing gas such as O 2 , N 2 O or the like, or a reactive gas such as H 2 , a more effective decomposition of --CH radicals, --OH radicals or the like from the organic oxysilane is carried out by the radicals, ions, or the like of such a gas. As a result, the generation of O 2 radicals and H 2 radicals, both having an ashing effect, can largely be decreased, thereby preventing the ashing of the substrate.
Further, if a fluorine group gas such as CF 4 , NF 3 or the like is added, --CH radicals, --OH radicals, --H radicals or the like of organic oxysilane as the raw gas are selectively decomposed. In this manner, the speed of film formation can be increased while preventing the ashing of the substrate.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other objects and the attendant advantages of the present invention will become readily apparent by reference to the following detailed description when considered in conjunction with the accompanying drawings wherein:
FIGS. 1A and 1B are schematic views showing a process of film formation of a passivation film on the surface of a substrate according to a first example of the present invention;
FIGS. 2A, 2B and 2C are schematic views showing a process of film formation of a passivation film on the surface of a substrate according to another example of the present invention; and
FIGS. 3A and 3B are schematic views showing a process of film formation of a passivation film on the surface of a substrate according to a conventional method.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
As a substrate on which a passivation film of SiO 2 is formed, there can be listed a plastic material such as an epoxy resin, polycarbonate resin, ABS resin, acrylic resin or the like.
As an apparatus to be used in carrying out a plasma CVD process for forming the SiO 2 film on the surface of a substrate, there can be listed a capacity coupling type apparatus and an inductive coupling type apparatus.
As an organic oxysilane to be used as a raw gas, there can be listed TMOS (tetramethoxysilane or tetramethyl orthosilicate: Si(OCH 3 ) 4 ), siloxane aside from TEOS (tetraethoxysilane or tetraethyl orthosilicate: Si(OC 2 H 5 ) 4 ).
As a fluorine group gas to be added to a reactive gas of Ar, He or NH 3 , there can be listed CF 4 , NF 3 or the like. The amount of addition of the fluorine group gas may be from 0% to about 20% by volume from the viewpoint of manufacturing cost.
The temperature at which an SiO 2 passivation film is formed on the surface of the substrate may be selected within such a range that the substrate made of a plastic material such as an epoxy resin, polycarbonate resin, ABS resin, acrylic resin or the like is not thermally deformed.
Specific embodying examples of the present invention will now be explained together with a comparative example.
EXAMPLE 1
This is an example for forming a passivation film by plasma CVD process in the presence of TEOS (tetraethoxysilane or tetraethyl orthosilicate: Si(OC 2 H 5 ) 4 ) and Ar gas.
As a substrate there was used an epoxy resin which has on its surface projections which are square in cross section, each projection being 0.3 mm wide and 0.3 mm high with a distance of 0.6 mm therebetween. As an organic oxysilane for a raw gas, there was used TEOS. Ar gas was used as a reactive gas which serves as an auxiliary for decomposing the raw gas. A parallel plate type apparatus was used as the plasma CVD apparatus. A passivation film of SiO 2 was formed on the substrate by introducing the raw gas under the conditions in which the internal pressure of the apparatus was 100 Pa, the partial pressure of Argon was 90 Pa, and 1000 V was applied as a high-frequency power source. The speed of forming the film was 40 nm/min. The temperature for forming the passivation film was 150° C.
Upon checking the surface of the substrate after the film formation, an SiO 2 film was found to have been formed uniformly on the surface of the substrate to a thickness of 2 μm without the surface of the substrate being subjected to ashing.
The process of forming the passivation film of SiO 2 on the surface of the substrate is shown in FIGS. 1(A) and 1(B).
First, as shown in FIG. 1(A), radicals 2 (shown by arrows) that were generated in the presence of TEOS and Ar reached the surface of the substrate 1. Formation of the passivation film 3 consisting essentially of SiO 2 immediately started on the surface of the substrate 1 by means of the radicals 2.
When the film forming step was continued for a predetermined period of time, there was attained a condition as shown in FIG. 1(B) in which the passivation film 3 of SiO 2 was formed smoothly to a uniform thickness on the surface of the substrate 1.
EXAMPLE 2
This is an example for forming an initial or preliminary passivation film by plasma CVD process in the presence of TEOS and Ar gas and then a passivation film by plasma CVD process in the presence of TEOS and O 2 gas.
As a substrate there was used an epoxy resin which has on its surface square projections which are square in cross section, each projection being 0.3 mm wide and 0.3 mm high with a distance of 0.6 mm therebetween. As an organic oxysilane for the raw gas, there was used TEOS. Argon gas was used as a reactive gas which serves as an auxiliary for decomposing the raw gas. A parallel plate type apparatus was used as the plasma CVD apparatus. An initial passivation film of SiO 2 of 200 nm thick was formed on the surface of the substrate by introducing the raw gas under the conditions in which the internal pressure of the apparatus was 100 Pa, the partial pressure of Ar gas was 90 Pa, and 1000 V was applied as a high-frequency power source.
Subsequently, a latter or remaining passivation film was formed on top of the initial passivation film by plasma CVD process under conditions of introducing O 2 gas, in place of Ar gas, at a partial pressure of 90 Pa. The speed of forming the initial passivation film was 40 nm/min and the speed of forming the latter passivation film was 40 nm/min. The temperature for forming the passivation films was 150° C.
Upon checking the surface of the substrate after the film formation, a passivation film of SiO 2 was found to have been formed on the surface of the substrate to a thickness of 2 μm without the surface of the substrate being subjected to ashing.
The process of forming the passivation film of SiO 2 on the surface of the substrate is shown in FIGS. 2(A) through 2(C).
As shown in FIG. 2(A), radicals 2 (shown by arrows) that were generated in the presence of TEOS and Ar gas first reached the surface of the substrate 1, and the formation of the initial passivation film 4 consisting essentially of SiO 2 on the surface of the substrate 1 immediately started by means of the radicals 2.
When the film forming was performed for a predetermined period of time, there was attained a condition, as shown in FIG. 2(B), in which the initial passivation film 4 of SiO 2 was smoothly formed on the surface of the substrate 1 to a uniform thickness.
Subsequently, when O 2 gas as a reactive gas was introduced in place of Ar gas, radicals 5 (shown by arrows) generated in the presence of TEOS and O 2 gas reached the surface of the initial passivation film 4 and the formation, on top thereof, of the passivation film 6 consisting essentially of SiO 2 immediately started by means of the radicals 5.
When the film formation was performed for a predetermined period of time, a condition was attained, as shown in FIG. 2(C), in which the passivation film 6 of SiO 2 in the presence of TEOS and O 2 gas was smoothly formed to a uniform thickness on top of the initial passivation film 4 (in the presence of TEOS and Ar gas) on the surface of the substrate 1.
In the above-described Example 2, an example was given of forming an initial or preliminary passivation film by plasma CVD process in the presence of TEOS and Ar gas and then a passivation film by plasma CVD process in the presence of TEOS and O 2 gas. The passivation film may also be formed by plasma CVD process in the presence of TEOS and O 3 gas.
Comparative Example 1
This is a comparative example for forming a passivation film by a conventional plasma CVD process in the presence of TEOS and O 2 gas.
As a substrate there was used an epoxy resin which has on its surface projections which are square in cross section, each projection being 0.3 mm wide and 0.3 mm high with a distance of 0.6 mm therebetween. As an organic oxysilane for the raw gas, there was used TEOS. O 2 gas was used as a reactive gas which serves as an auxiliary for decomposing the raw gas. A parallel plate type apparatus was used as the plasma CVD apparatus. A passivation film of SiO 2 was formed on the surface of the substrate by introducing the raw gas under conditions in which the internal pressure of the apparatus was 100 Pa, the partial pressure of O 2 was 90 Pa, and 1000 V was applied as a high-frequency power source. The speed of forming the film was 40 nm/min.
Upon checking the surface of the substrate after the film formation, the surface of the substrate was found to have been subjected to ashing into a rough surface with projections and depressions. The projections remained projected as if they were subjected to landslide. In addition, the thickness of the passivation film that was formed on the surface of the substrate was not uniform.
The process of forming the passivation film of SiO 2 on the surface of the substrate is shown in FIGS. 3(A) and 3(B).
As shown in FIG. 3(A), when the radicals 8 (shown by arrows) that were generated in the presence of TEOS and O 2 gas reached the surface (shown by an imaginary line) of the substrate 7, the surface of the substrate 7 was deformed through ashing by the oxygen radicals. Also there started the formation of the passivation film consisting essentially of SiO 2 on the deformed surface of the substrate 7 by the radicals 8 that were generated in the presence of TEOS and O 2 gas.
When the film formation was performed for a predetermined period of time, the surface of the substrate 7 was largely ashed as shown in FIG. 3(B) and became a condition in which the passivation film 9 of SiO 2 was slightly formed on the ashed surface of the substrate 7.
As can be clearly seen from the results of the Examples 1 and 2 and Comparative Example 1, it has been confirmed in the Examples of the present invention that a passivation film of SiO 2 of good quality can be smoothly formed to a uniform thickness in conformity with the shape of the substrate. It follows that the method of the present invention is superior in step coverage or characteristics or properties in coating irregularly shaped or stepped portions.
EXAMPLE 3
This is an example for forming a passivation film by plasma CVD process in the presence of TEOS and He gas.
The passivation film of SiO 2 was formed on the surface of the substrate in the same manner as in the Example 1 except for the fact that He gas was used as the reactive gas and that the partial pressure of He was made to be 90 Pa.
Upon checking the surface of the substrate after the film formation, an SiO 2 film was found to have been formed uniformly on the surface of the substrate to a thickness of 2 μm without the surface of the substrate being subjected to ashing. The speed of forming the film was 38 nm/min.
EXAMPLE 4
This is an example for forming a passivation film by plasma CVD process in the presence of TEOS and NH 3 gas.
The passivation film of SiO 2 was formed on the surface of the substrate in the same manner as in the Example 1 except for the fact that NH 3 gas was used as the reactive gas and that the partial pressure of NH 3 was made to be 90 Pa.
Upon checking the surface of the substrate after the film formation, an SiO 2 film was found to have been formed uniformly on the surface of the substrate to a thickness of 2 μm without the surface of the substrate being subjected to ashing. The speed of film formation was 38 nm/min.
EXAMPLE 5
This is an example for forming a passivation film by plasma CVD process in the presence of TEOS, Ar and CF 4 gas.
The passivation film of SiO 2 was formed on the surface of the substrate in the same manner as in the Example 1 except for the fact that a mixture gas obtained by adding 5% by volume of CF 4 gas to Ar gas was used as the reactive gas and that the partial pressure of the mixture gas was made to be 90 Pa.
Upon checking the surface of the substrate after the film formation, an SiO 2 film was found to have been formed uniformly on the surface of the substrate to a thickness of 2 μm without the surface of the substrate being subjected to ashing. The speed of film formation was 50 nm/min.
By adding CF 4 gas to the reactive gas (Ar) as in the present Example, the speed of film formation (50 nm/min) can be increased as compared with the film formation speed (40 nm/min) in an example (Example 1) in which only Ar gas was used as the reactive gas.
EXAMPLE 6
This is an example for forming a passivation film by plasma CVD process in the presence of TEOS, He gas and NF 3 gas.
The passivation film of SiO 2 was formed on the surface of the substrate in the same manner as in the Example 1 except for the fact that a mixture gas obtained by adding 5% by volume of NF 3 gas to He gas was used as the reactive gas and that the partial pressure of the mixture gas was made to be 90 Pa.
Upon checking the surface of the substrate after the film formation, an SiO 2 film was found to have been formed uniformly on the surface of the substrate to a thickness of 2 μm without the surface of the substrate being subjected to ashing. The speed of film formation was 50 nm/min.
EXAMPLE 7
This is an example for forming an initial passivation film by plasma CVD process in the presence of TEOS and Ar gas and then forming thereon a passivation film by plasma CVD process in the presence of TEOS and N 2 O gas.
The latter passivation film of SiO 2 was formed on the surface of the initial passivation film which was on the surface of the substrate in the same manner as in the Example 2 except for the fact that N 2 O gas was used as the reactive gas and that the partial pressure of the N 2 O gas was made to be 90 Pa.
Upon checking the surface of the substrate after the film formation, an SiO 2 film was found to have been formed uniformly on the surface of the substrate to a thickness of 2 μm without the surface of the substrate being subjected to ashing. The speed of film formation of the initial passivation film was 40 nm/min and that of the latter passivation film was 40 nm/min.
EXAMPLE 8
This is an example for forming first an initial passivation film by plasma CVD process in the presence of TEOS and He gas and then forming thereon a passivation film by plasma CVD process in the presence of TEOS and H 2 gas.
After having formed the initial passivation film of SiO 2 on the surface of the substrate, the latter passivation film of SiO 2 was formed on the surface of the initial passivation film in the same manner as in the above-described Example 2 except for the fact that He gas was used as the reactive gas for forming the initial passivation film, that the partial pressure of the He gas was made to be 90 Pa, that H 2 gas was used as the reactive gas for forming the latter passivation film, and that the partial pressure of the H 2 gas was made to be 90 Pa.
Upon checking the surface of the substrate after the film formation, an SiO 2 film was found to have been formed uniformly on the surface of the substrate to a thickness of 2 μm without the surface of the substrate being subjected to ashing. The speed of film formation of the initial protection film was 40 nm/min and that of the latter protection film was 40 nm/min.
EXAMPLE 9
This is an example for forming first an initial passivation film by plasma CVD process in the presence of TEOS, NH 3 gas and CF 4 gas and then forming thereon a passivation film by plasma CVD process in the presence of TEOS and O 2 gas.
After having formed the initial passivation film of SiO 2 on the surface of the substrate, the latter passivation film of SiO 2 was formed on the surface of the initial passivation film in the same manner as in the above-described Example 2 except for the fact that a mixture gas obtained by adding 5% by volume of CF 4 gas to NH 3 gas was used as the reactive gas for forming the initial passivation film, that the partial pressure of the mixture gas was made to be 90 Pa, that O 2 gas was used as the reactive gas for forming the latter passivation film, and that the partial pressure of the O 2 gas was made to be 90 Pa.
Upon checking the surface of the substrate after the film formation, an SiO 2 film was found to have been formed uniformly on the surface of the substrate to a thickness of 2 μm without the surface of the substrate being subjected to ashing. The speed of film formation of the initial protection film was 50 nm/min and that of the latter protection film was 40 nm/min.
EXAMPLE 10
This is an example for forming first an initial passivation film by plasma CVD process in the presence of TEOS, He gas and NF 3 gas and then forming thereon a passivation film by plasma CVD process in the presence of TEOS and H 2 gas.
After having formed the initial passivation film of SiO 2 on the surface of the substrate, the latter passivation film of SiO 2 was formed on the surface of the initial passivation film in the same manner as in the above-described Example 2 except for the fact that a mixture gas obtained by adding 5% by volume of NF 3 gas to He gas was used as the reactive gas for forming the initial passivation film, that the partial pressure of the mixture gas was made to be 90 Pa, that H 2 gas was used as the reactive gas for forming the latter passivation film, and that the partial pressure of the H 2 gas was made to be 90 Pa.
Upon checking the surface of the substrate after the film formation, an SiO 2 film was found to have been formed uniformly on the surface of the substrate to a thickness of 2 μm without the surface of the substrate being subjected to ashing. The speed of film formation of the initial protection film was 50 nm/min and that of the latter protection film was 40 nm/min.
EXAMPLE 11
This is an example for forming first an initial passivation film by plasma CVD process in the presence of TEOS, Ar gas and CF 4 gas and then forming thereon a passivation film by plasma CVD process in the presence of TEOS and N 2 O gas.
After having formed the initial passivation film of SiO 2 on the surface of the substrate, the latter passivation film of SiO 2 was formed on the surface of the initial passivation film in the same manner as in the above-described Example 2 except for the fact that a mixture gas obtained by adding 5% by volume of CF 4 gas to Ar gas was used as the reactive gas for forming the initial passivation film, that the partial pressure of the mixture gas was made to be 90 Pa, that N 2 O gas was used as the reactive gas for forming the latter passivation film, and that the partial pressure of the N 2 O gas was made to be 90 Pa.
Upon checking the surface of the substrate after the film formation, an SiO 2 film was found to have been formed uniformly on the surface of the substrate to a thickness of 2 μm without the surface of the substrate being subjected to ashing. The speed of film formation of the initial protection film was 50 nm/min and that of the latter protection film was 40 nm/min.
EXAMPLE 12
This is an example for forming a passivation film by plasma CVD process in the presence of TEOS and Ar gas.
A passivation film of SiO 2 was formed on the surface of the substrate in the same manner as in the above-described Example 1 except for the fact that an acrylic resin was used as the resin material for the substrate.
Upon checking the surface of the substrate after the film formation, an SiO 2 film was found to have been formed uniformly on the surface of the substrate to a thickness of 2 μm without the surface of the substrate being ashed. The speed of film formation was 40 nm/min.
EXAMPLE 13
This is an example for forming a passivation film on a polycarbonate (plastic) substrate by plasma CVD process in the presence of TEOS and He gas.
A passivation film of SiO 2 was formed on the surface of the substrate in the same manner as in the above-described Example 1 except for the fact that a polycarbonate (plastic) was used as the plastic material for the substrate, that He gas was used as the reactive gas, and that the partial pressure of the He gas was made to be 90 Pa.
Upon checking the surface of the substrate after the film formation, an SiO 2 film was found to have been formed uniformly on the surface of the substrate to a thickness of 2 μm without the surface of the substrate being subjected to ashing. The speed of film formation was 40 nm/min.
EXAMPLE 14
This is an example for forming a passivation film on an epoxy-based resin (substrate) by plasma CVD process using TMOS (tetramethyl orthosilicate: Si(OCH 3 ) 4 ) as a raw gas in the presence of TMOS and NH 3 gas.
A passivation film of SiO 2 was formed on the surface of the substrate in the same manner as in the above-described Example 1 except for the fact that TMOS was used as the raw gas, that NH 3 was used as the reactive gas, and that the partial pressure of NH 3 was made to be 90 Pa.
Upon checking the surface of the substrate after the film formation, an SiO 2 film was found to have been formed uniformly on the surface of the substrate to a thickness of 2 μm without the surface of the substrate being subjected to ashing. The speed of film formation was 40 nm/min.
As described hereinabove, according to the present invention, when the passivation film of SiO 2 is formed by plasma CVD process on the surface of the substrate by decomposing the raw gas, one of Ar, He and NH 3 gases was used as the reactive gas which serves as an auxiliary for decomposing the raw gas. Therefore, a good passivation film of SiO 2 of uniform thickness can be formed in conformity with the shape of the surface of the substrate, without the surface of the substrate being subjected to ashing.
Further, the speed of film formation can be increased by adding a fluorine group gas such as CF 4 and NF 3 to the reactive gas.
In case an initial passivation film of SiO 2 is first formed by plasma CVD process by decomposing the raw gas by using one of Ar, He and NH 3 as a reactive gas to serve as an auxiliary in decomposing the raw gas, and then a latter passivation film of SiO 2 is formed on top of the initial passivation film by plasma CVD process by decomposing the raw gas by using an oxidizing gas, such as O 2 , N 2 O or O 3 , or H 2 gas as the reactive gas, the surface of the substrate is not subjected to ashing and a passivation film which is equal to the conventionally obtained passivation film of SiO 2 can be obtained, without causing ashing to take place on the surface of the substrate.
It is readily apparent that the above-described method of forming a passivation film meets all of the objects mentioned above and also has the advantage of wide commercial utility. It should be understood that the specific form of the invention hereinabove described is intended to be representative only, as certain modifications within the scope of these teachings will be apparent to those skilled in the art.
Accordingly, reference should be made to the following claims in determining the full scope of the invention. | An SiO 2 passivation film is formed on a surface of a substrate made of a plastic material by plasma chemical vapor deposition (CVD) process in which organic oxysilane is used as a raw gas. Instead of a reactive gas having an ashing effect, Ar, He or NH 3 is used as a reactive gas which serves as an auxiliary for decomposing the raw gas at a temperature not greater than a temperature at which the substrate is thermally deformed (i.e., about 250° C.). The ashing of the substrate by oxygen or hydrogen radicals is thus prevented. | 2 |
CROSS REFERENCE TO RELATED APPLICATIONS
The present application is a 35 U.S.C. §371 National Phase conversion of PCT/JP2007/071511, filed Nov. 6, 2007, which claims benefit of Japanese Application No. 2006-304225, filed Nov. 9, 2006 and Japanese Application No. 2006-304226, filed Nov. 9, 2006, the disclosures of which are incorporated herein by reference. The PCT International Application was published in the Japanese language.
BACKGROUND OF THE INVENTION
The present invention relates to a desk top panel on the upper surface of a top board of a desk to block visibility of a person and a desk with the desk top panel.
Such a desk top panel is a perfectly-partitioned type as disclosed in JP2004-313471A. There is also a desk top panel where only upper part is partitioned and lower part comprises only posts for supporting the upper part to create openings between the posts.
JP2006-6771A discloses a wire storage space under a desk top panel.
Furthermore, JP3-98634U, JP2000-287758A and JP2006-149554A disclose an opening in a top board of a desk, wires for lighting instruments on the top board and electronic equipment being introduced to a wire duct through the opening, the opening being closed by a wire cover.
In JP2004-313471A, privacy of face-to-face persons who sit in front of the desk or table can be protected with the partitioning desk top panel, but one has to walk around the corner of the desk or table when one need talk to the other or give documents.
The lower-part open type provides advantage contrary to the above, but it is possible to see through the lower space, so that one's privacy is invaded.
In JP2006-6771A, a wire storage space is formed beside the desk top panel in the top board, so that an effective working area on the top board is reduced.
In JP3-98634U, JP2000-287758A and JP2006-149554A, when the desk top panel is mounted, the wire cover may be obstructed from opening/closing and taking on/off, and wiring will become more difficult.
When the wire opening is along the desk top panel, a working space is reduced, so that the top board will be less effective in use.
SUMMARY OF THE INVENTION
In view of the disadvantages, it is an object of the invention to provide a desk top panel and a desk with the desk top panel, the desk being normally partitioned by a desk top panel to protect privacy, lower part of the desk top panel being opened, if necessary, to enable face-to-face persons to talk with each other and to give/receive documents, a wire cover being easily removed or opened.
It is another object of the invention to provide a desk top panel having a wire storage space under a desk top panel without reducing effective working area on a top board of the desk.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view showing a desk with the first embodiment of a desk top panel according to the present invention.
FIG. 2 is an exploded perspective view showing an intermediate part of the desk top panel.
FIG. 3 is an enlarged vertical sectional side view thereof.
FIG. 4 is an enlarged vertical sectional side view showing a desk with the second embodiment of a desk top panel according to the present invention.
FIGS. 5A-5C are enlarged sectional views of the part V in FIG. 4 .
FIGS. 6A and 6B are perspective views showing the steps for assembling a closing member.
FIG. 7 is an exploded perspective view of the main part in the third embodiment of the present invention.
FIGS. 8A-8C are views showing a motion thereof.
FIGS. 9A-9C are views showing a motion in the fourth embodiment.
FIG. 10 is a vertical sectional side view of the fifth embodiment of the present invention.
FIG. 11 is an exploded perspective view of the sixth embodiment of a desk top panel according to the present invention.
FIG. 12 is a vertical sectional side view thereof.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
FIGS. 1-3 show the first embodiment of the invention.
In FIG. 1 , a desk 1 comprises four top boards 2 in which the two boards face each other, while the two boards are arranged side by side. The top boards 2 are supported by a top support A comprising a pair of side panels 3 , 3 ; intermediate legs 4 therebetween; and a beam (not shown) for connecting the intermediate legs 4 . The desk 1 is a face-to-face type.
Between the top boards 2 and 2 , there is provided a desk top panel 5 for blocking front visibility of sitting persons on a chair 6 , shown by two-dot-dash lines in front of each of the top boards 2 .
Under each of the top boards 2 , there is a side wagon 7 as shown by two-dot-dash lines beside the chair 6 . On the upper surface of the top board 2 , there are a notebook computer 8 in two-dot-dash lines and other electric appliance (not shown). A power source code and a connecting cable pass through an elongate opening 9 between the top boards 2 and 2 under the desk top panel 5 and is stored in a wire duct 10 in FIG. 3 .
In FIG. 3 , the wire duct 10 comprises a long U-shape and the side edge thereof is fixed on the lower surface of the facing top boards 2 , 2 with a plurality of support plates 11 with a screw 12 .
The opening 9 is closed with a detachable wire cover 13 .
The wire cover 13 is formed by bending the edges of a horizontal steel plate into a U-shape and located on the middle of the support plate 11 while a gap 14 through which a wire passes still remains, such that the middle of the opening 9 is coplanar with the upper surface of the top board 2 .
In the middle of the support plate 11 , a pair of upward projections 11 a . 11 a is provided to place the wire cover 13 in the middle.
In FIGS. 2 and 3 , the desk top panel 5 comprises a pair of vertical frames 16 , 16 having a mounting base 15 at the lower end; an upper horizontal frame 9 connecting the upper ends of the vertical frames 16 , 16 ; a lower horizontal frame 18 connecting parts close to the lower ends of the vertical frame 18 ; a pair of rectangular decoration panels 19 , 19 surrounded by the frames 16 , 17 , 18 ; and a closing member 21 the upper end of which is pivotally mounted to the vertical frames 16 , 16 on a shaft 20 under the lower horizontal frame 18 .
A body 5 A of the desk top panel 5 comprises the vertical frames 16 , 16 higher than the lower horizontal frame 18 ; the lower horizontal frame 18 ; and the decoration panels 19 , 19 . A pair of mounting portions 5 B comprises the vertical frames 16 , 16 lower than the lower horizontal frame 18 ; and the mounting bases 15 , 15 . The mounting portion 5 B which suspends from the lower end of the body 5 A is mounted at the lower end to the top board 2 or top board support A.
In this embodiment, the shaft 20 passes through the upper part of the closing member 21 and projects at the end which rotatably fits in a bearing hole 22 in the inner surfaces of the vertical frame 16 , 16 .
The mounting bases 15 , 15 of the mounting portion 5 B is disposed on the upper surface of the bottom of the wire duct 10 through the opening 9 and mounted with a bolt 23 and a nut 24 . Thus, the desk top panel 5 is firmly fixed to the top board support A.
The mounting bases 15 , 15 may be directly fixed to the side panel 3 , intermediate leg 4 or other member of the top board support A. Particularly, in a desk comprising a single top board, mounting bases 15 , 15 may be fixed to the upper surface of the top board.
The closing member 21 may be made in proper size to close a space S between the lower end of the body 5 A and the upper surface of the top board 2 of the desk 1 when the desk top panel 5 is mounted to the top board support A as above.
As shown by sold lines in FIG. 3 , the closing member 21 is normally positioned in a close position by its own weight and closes the space S almost perfectly. The front visibility of the person sitting on the chair 6 is blocked almost perfectly, so that privacy can be protected.
From this position, the person pushes the closing member with a finger forward or backward. As shown by two-dot-dash lines in FIG. 3 , the closing member 21 turns to an open position around the shaft 20 to produce the space S to allow one at one side to look at the other at the other side of the desk top panel 5 . The space S also enables one to give a document to the other.
The wire cover 13 can be removed from a opening-closing position while the closing member 21 is held in an open position.
The wire cover 13 is removed from the opening 9 to make the opening 9 greater, allowing wires to be stored or removed more easily.
FIGS. 4-6 show the second embodiment of the invention. The same numerals are allotted to the same members as the foregoing embodiment, and detailed description thereof is omitted.
In FIG. 4 , an engagement groove 26 is formed at the lower part of a lower horizontal frame 25 . In FIG. 6 , a plurality of shaft-support blocks 27 engage in the engagement groove 26 at regular intervals. The shaft-support block 27 has a lower semicircular section. In the lower part and sides of the outer circumference of the semicircular section, positioning elastic engagement projections 28 are provided, and a shaft 30 projects from the sides of the shaft-support block 27 at the center of the semicircular section, and the closing member 29 turns with the shaft 30 . The shaft 30 may be integrally formed with the shaft-support block 27 .
A closing member 29 is molded of synthetic resin and has a pair of arc-like elastically deformable shaft-holding portions 29 a , 29 a at the upper end. In the middle of the upper end of the closing member 29 , there is formed a groove 31 for improving elastic flexibility of the shaft-holding portions 29 a , 29 a . An elastic engagement projection of the shaft-support block 27 fits in the groove 31 .
To the shaft support blocks 27 mounted to the lower end of the lower horizontal frame 25 in FIG. 6A , the closing member 29 is pressed up in FIGS. 6A and 5A . In FIGS. 5B and 6B , the shaft 30 is held by the shaft-holding portions 29 a at the ends projecting from the shaft-support block 27 . The elastic engagement projection 28 at the lower end of the shaft-support block 27 fits in the groove 31 .
The closing member 29 is stably held in a closed position by engagement of the elastic engagement projection 28 in the groove 31 .
Then, the closing member 29 turns forward or backward around the shaft 30 . For example, in FIG. 5C , in the backward open position, the groove 31 engages with the elastic engagement projection 28 at the rear surface of the shaft-support block 27 to allow the closing member 29 to be held stably in the open position.
The wires can be taken in and out of the opening 9 easily.
In this embodiment, the closing member 29 is stably held in the closed and open positions by holding means comprising the groove 31 and the three elastic engagement projections 28 . Accordingly, the closing member 29 need not to be held with a hand in the open position and does not swing to the closed position.
The third embodiment of the invention is shown in FIGS. 7 and 8 .
In the embodiment, a pair of shaft support blocks 33 is fixed to the sides of the lower end of a lower horizontal frame 32 , and each end of a shaft 35 around which the closing member 34 turns is pressed and fitted in the shaft support block 33 . An upper flat surface 35 a is formed on the shaft 35 and is corresponding in shape to an engagement hole 36 in the shaft-support block 31 .
The closing member 34 comprises a pair of elastically deformable shaft-holding portions 34 a , 34 a similar to the second embodiment. The distance between the shaft-holding portions 34 a and 34 a is smaller than an external diameter of the shaft 35 . In FIG. 8A , when the closing member 34 is in the closed position, the shaft-holding portions 34 a , 34 a expands at largest, and the side edge of the flat surface 35 a of the shaft 35 is held by the shaft-holding portions 34 a , 34 a stably in the closed position. In FIG. 8C from FIG. 8B , when the closing member 34 turns to the open position, the shaft 35 is held while one of the shaft-support portions 34 a is placed on the flat portion of the shaft 35 , so that the closing member 34 is stably held.
In the third embodiment, similar function and advantages to the second embodiment can be achieved.
FIG. 9 shows the fourth embodiment of the invention. In FIG. 9A , a shaft-support block 39 engages in an engagement groove 38 and has a rectangular-sectioned shaft 40 therefrom.
At the upper end of the closing member 41 , an axial hole 42 which fits the shaft 40 is formed and a gap 43 communicates with the axial hole 42 .
In FIG. 9A , when the closing member 41 is in the closed position, the inner surface of the axial hole 42 in the closing member 41 tightly contacts the outer circumference of the shaft 40 , so that the closing member 41 is stably held.
The closing member 41 is pressed rearward and turned around the shaft 40 . In FIG. 9B , at a turning angle for 45 degrees from the closed position, the axial hole 42 and its outer circumference at the upper end of the closing member 41 are elastically deformed to expand at largest. Besides the angle, elastic deformation of the axial hole 42 and its circumference gradually decreases. When the closing member 41 reaches an open position in FIG. 9C , the inner surface of the axial hole 42 tightly contacts the outer circumferential surface of the shaft 40 , so that the closing member 41 is stably held.
The fourth embodiment achieves function and advantages similar to the second and third embodiments. The closing member 41 can be forced so as to reverse a turning direction at the intermediate position between the closed position and open position.
The shaft 40 and axial hole 42 may be provided in the closing member 41 and shaft-support block 39 respectively.
The shaft 40 and axial hole 42 may be like a polygon such as a hexagon to allow the closing member 41 to be held stably.
FIG. 10 shows the fifth embodiment of the invention.
In the embodiment, similar to the first embodiment, the upper end of a closing member 21 is pivotally mounted to vertical frames 16 , 16 on a shaft 20 . The closing member 21 is pivotally mounted to the vertical frames 16 , 16 on a shaft 20 . The closing member 21 is thinner than a lower horizontal frame 18 . The closing member 21 is disposed in the middle of the lower horizontal frame 18 . When the closing member 21 is in a closed position, there are recesses 44 , 44 in front of and behind the closing member 21 under a body 5 A of a desk top panel 5 . Swaying wire cover 45 , 45 for an opening 9 turns upward to allow the wire cover 45 to be stored into the recesses 44 when the opening 9 is open.
A plurality of cover supports 47 is arranged at regular intervals and has mounting portion 47 a at the lower end fixed with a bolt and a nut 46 to the bottom of the wire duct 10 . The wire covers 45 , 45 are pivotally mounted to the upper end of the cover supports 47 on pivot shafts 48 , 48 and turns with the pivot shaft 48 between a horizontal closed position coplanar with a top board 2 as shown by solid lines in FIG. 10 and an open position as shown by two-dot-dash lines.
On the lower side of the wire cover 45 , there is provided an engagement projection 45 a which elastically engages with an engagement portion 47 b extending from the upper end of the cover support 47 . When the wire cover 45 turns from the open position to the closed position, the engagement projection 45 a elastically engages with the engagement portion 47 b to allow the wire cover 45 to be elastically held in the closed position.
The wire cover 45 turns upward to the open position. When the opening 9 is open, each of the wire covers 45 is stored in the recess 44 , allowing the opening 9 to open larger to facilitate wires to be taken in and out of the wire duct 10 .
The opening 9 can be provided close to the desk top panel 5 , thereby providing broader working space on the top board 2 .
The sixth embodiment is shown in FIGS. 11 and 12 .
In the embodiment, wire covers 45 , 45 have the same structure as those in the fifth embodiment. There is provided a suspension 49 thinner than the lower horizontal frame 18 at the lower end of a body 5 A of a desk top panel 5 or in the middle of the lower surface of a lower horizontal frame 18 . There are grooves 50 , 50 on the lower end of the desk top panel 5 , When the wire covers 45 , 45 turns upward to open an opening 9 , the wire covers 45 are stored in the grooves 50 , 50 .
Each of the wire covers 45 turns to an open position to make the opening 9 broader, allowing wires to be taken in and out of a wire duct 10 easily. The opening 9 can become close to the desk top panel 5 , making working space on a top board broader.
The present invention is not limited to the foregoing embodiments, but variations may be made without departing from the scope of claims.
For example, in the foregoing embodiments, the desk 1 comprises face-to-face connected desks, but the present invention can apply to a single top board desk.
In this case, the desk top panel 5 may be mounted not only to the top board support A but also to the top board 2 directly. The opening 2 may comprise an elongate hole at the rear part of the top board 2 or may be cut away forward from the rear end of the top board 2 . | Provided is a desk top panel, which normally protects privacy in a complete shielding form, permits facing persons to converse and documents and the like to be passed and received by opening a lower space of the desk top panel as needed, and permits a wiring cover to be easily attached/removed or opened/closed. A desk having such desk top panel attached thereon is also provided. A desk top panel is attached to the rear portion of a top board of a desk to stand, for blocking the visual fields of sitting persons. The desk top panel is provided with a panel-like main body; a pair of right and left attaching sections, which vertically extend downward from the both lower end portions of the main body by having the lower end sections attached to the top board or a top board supporting body of the desk; and a closing plate, attached to the lower end of the main body to be opened/closed, so that a space formed between the main body and the upper surface of the top board of the desk can be opened/closed when both the attaching sections are attached to the desk. | 0 |
[0001] This application is a continuation-in-part of U.S. application Ser. No. 11/448,851 filed on Jun. 8, 2006 and a continuation-in-part of U.S. patent application Ser. No. 11/433,445 filed on May 15, 2006 which is a divisional of U.S. patent application Ser. No. 09/740,965 filed on Dec. 21, 2000, which is a divisional of application Ser. No. 09/035,152 filed on Mar. 5, 1998, now U.S. Pat. No. 6,209,610, which is a continuation-in-part of application Ser. No. 08/962,263 filed Oct. 31, 1997, now U.S. Pat. No. 6,446,696, which is a continuation-in-part of application Ser. No. 08/362,995 filed Dec. 23, 1994, now U.S. Pat. No. 5,687,506, which is a continuation-in-part of application Ser. No. 08/281,620 filed Jul. 28, 1994, now U.S. Pat. No. 5,682,710, from which priority is claimed.
FIELD OF INVENTION
[0002] This invention relates to improvements to roller assemblies and specifically embodied on a roller cassette to be used with closure assemblies. In one example the frame of a window assembly includes both a bug screen and a blind material provided with a replaceable roller cassette disposed within opposite jamb sections of a window assembly.
BACKGROUND OF THE INVENTION
[0003] It is well known to provide roller blinds for windows. Typically these roller blinds are included on a roller assembly that is mounted above a typically window. The roller blind is pulled down over the window and blocks the sunlight. Normally, the roller blind is mounted on brackets that are positioned above the frame of the window or alternatively maybe installed on the frame of the window.
[0004] Such an installation is inconvenient, clumsy, and unattractive. The roller blind assembly is visible at all times and may disrupt the appearance of the window and detract from decorating scheme of a particular room.
[0005] Roll out screen assemblies are well known and may be provided as a supplementary assembly to be installed on a jamb of a window assembly such as those manufactured and sold by the Phantom® or screens are alternatively as sold by Preferred Engineering Ltd. including bug screen mesh installed on a roller assembly which is hidden within the hollow of a jamb of a window assembly as disclosed in the U.S. Pat. No. 6,209,610 owned by the assignee of this application. The disclosure of that application is incorporated by reference in its entirety with respect to the teachings of roll out mesh screen assemblies, from which this application claims priority and specifically from U.S. patent application Ser. No. 11/433,445 filed on May 15, 2006 a divisional of the granted U.S. Pat. No. 6,209,xxx.
[0006] In the prior patent literature of Preferred Engineering there is also taught that the mesh screen material on the roll out screen assembly may alternatively be other screen like materials, for example solar screens and blind material. So, one may substitute therefore blind material for the bug mesh provided in the teachings of the U.S. Pat. No. 6,209,610. Prior filed co-pending application U.S. application Ser. No. 11/448,851 filed on Jun. 8, 2006 presently co-pending and from which this application claims CIP status, teaches in for example claim 12 that the roll out screen assembly provided in the supporting frame may include French door type assemblies wherein the screens extend from either vertical frame section and engage proximate the center of the assembly. It is further discussed that in this French door alternative one side may be blind material and the other side may include bug screen material. Applicant has discovered that this scenario would also be operative in various windows and doors assembly structures which include Applicants roller assemblies hidden within a pocket of a frame section. Applicant therefore has found that that installation would be extremely advantageous to the house holder by enabling a roll out screen assembly and a roll out solar screen assembly and a roll out blind assembly to be hidden within the pocket of window structures.
[0007] Is therefore a primary object of this invention to provide a roll out cassette assembly including solar blind, bug screen and blind materials which are disposed within frame elements of closure assemblies incorporating a pocket or, alternatively a housing proximate each side of a closure assembly.
[0008] It is a further object of the invention to provide a roller assembly for blind material which extends from one jamb section of the closure assembly and which also provides a bug screen roller assembly extending from the opposite jamb section of the closure assembly.
[0009] It is a further object of this invention to provide the above mentioned assemblies to improve; the aesthetics of the closure assembly, and the appearance to the home owner.
[0010] It is yet a further object of the invention to provide said roll out assembly which incorporates the aspect of being hidden until such time as it is desired to cover an opening in a building.
[0011] Further and other objects of the invention will become apparent to those skilled in the art when considering the following summary of the invention and the more detailed description of the preferred embodiments illustrated herein.
SUMMARY OF THE INVENTION
[0012] According to a primary aspect of the invention there is provided a closure assembly to be installed in an opening for a building, said closure assembly comprising a frame for supporting a moveable closure member therewithin, said frame including top, bottom and side members, one of the members including a hollow pocket within the interior of said member and for receiving a spring biased roller assembly upon which a flexible material is accumulated, said flexible material being selected from a blind, a bug screen, a solar screen, or the like, the flexible material being movable between a fully retracted first position whereat the material is contained within the pocket to a fully extended second position whereat the material covers some or all of the opening of the building.
[0013] Preferably flexible material extends from the hollow pocket of at least two opposing members of the frame.
[0014] In one embodiment one of the materials is solar screening and the second material is bug screening.
[0015] The closure assemblies may be selected from patio doors, double hung windows, single hung windows, tilt and slide windows with single movable and double movable sashes, casement windows, double casement windows, awning windows, exit doors and screen doors.
[0016] Preferably said members further comprise a header, sill, and two jambs.
[0017] Preferably in another embodiment two of the members include a hollow pocket.
[0018] In another embodiment said pocket is integrately formed with said member.
[0019] Preferably said spring biased roller assembly is fully contained in the pocket.
[0020] In another embodiment the other frame members, for example the header and the sill when the pocket is provided in opposing jambs, include track portions for guiding a leading edge of the flexible material to and from the first and second positions as the flexible material moves across the building opening.
[0021] Preferably a draw bar is connected to the leading edge of said flexible material which includes guides which ride in said track portions. In another embodiment said guides include retractable pins which are retracted by the operation of a preferred central locking mechanism provided with said draw bar.
[0022] More preferably said tracks include multiple locking detents for engagement with said retractable pins at a number of predefined positions along said track to enable positioning of the flexible material at those positions, such as for example in the case when the flexible material is a blind, these positions may further comprise fully extended, half extended and fully retracted positions.
[0023] In another embodiment said flexible material is bug screening extending from the pocket of one member, and blind material extending from the pocket of a second member.
[0024] In another embodiment when the closure assembly is a double casement window assembly and blind material or solar screening is disposed in the pocket of one of the frame members, the blind or solar screen is fully extendable across both casement windows, and also extends in a second manner across only one casement window, wherein the pocket of the opposing frame member may contain bug screening operating in the same manner. Preferably when bug screening extends from both pockets, and the draw bars thereof engage the track at predetermined positions, both screens combining to fully cover the full extent of the opening of the building.
[0025] According to yet another aspect of the invention there is provided a closure assembly comprising two ends and two sides and having disposed at each end, or alternatively each side, a housing containing a spring biased roller assembly upon which a flexible material is accumulated, the flexible material being moveable, from a fully retracted position in said housing to a fully extended position, within a track disposed with each side or alternatively at each end of the assembly, said track including a multiplicity of detent positions for retaining a leading edge of the flexible material extending from each spring biased roller assembly and for engaging said leading edge with said track at each of said positions, adjacent the leading edge of said flexible material, said leading edge including a draw bar with corresponding operative detents for engagement at said multiplicity of positions of each track, said flexible material being selected from solar screening, bug screening and blinds or the like, wherein when needed the applicable material may be moved between the fully retracted and fully extended positions for example a blind, or a solar screen.
[0026] According to still yet another aspect of the invention there is provided a screen assembly comprising two ends and two sides and having disposed at each end, or alternatively each side, a housing containing a spring biased roller assembly upon which a flexible material is accumulated, the flexible material being moveable, from a fully retracted position in said housing to a fully extended position, within a track disposed with each side or alternatively at each end of the assembly, said track including a multiplicity of detent positions for retaining a leading edge of the flexible material extending from each spring biased roller assembly and for engaging said leading edge with said track at each of said positions, adjacent the leading edge of said flexible material, said leading edge including a draw bar with corresponding operative detents for engagement at said multiplicity of positions of each track, said flexible material being selected from solar screening, bug screening and blinds or the like, wherein when needed the applicable material may be moved between the fully retracted and fully extended positions for example a blind, or a solar screen.
[0027] Preferably the screen assembly may further comprise an add on replacement screen assembly for a patio door or entry door.
[0028] Preferably said patio door may further comprise a French door assembly. In another embodiment of said screen assembly at least three housings are provided, each carrying flexible material on a roller cassette.
[0029] It is preferred that the flexible material for each cassette be unique but the flexible material for each cassette may also not be unique.
[0030] According to another aspect of the invention there is provided a system for readily interchanging the material covering an opening of a closure assembly including a spring biased roller cassette to be inserted in the pocket of a frame member of the closure assembly:
(a) providing a standard design for the cassette; (b) making available various materials extending between a draw bar and a roller for each cassette; (c) providing a standard pocket design to receive each cassette in such a manner that the cassette may be readily placed into and removed from the pocket; and (d) replacing the cassette as desired in the appropriate conditions;
wherein a homeowner may easily replace the material covering the opening of the closure assembly by interchanging the cassettes as desired. In one embodiment the system further comprises a roller assembly upon which the flexible material (as described above) is accumulated.
[0035] Preferably the system for interchanging the screen cassettes of abovementioned consists of at least two steps:
removal of a first cassette containing a first material from the pocket of the frame member, followed by the insertion of second cassette carrying a second material into the pocket of the frame member.
BRIEF DESCRIPTION OF THE DRAWINGS
[0038] FIG. 1 is a schematic perspective view of a double casement window with the blind S′ partially extended from the left jamb and the bug screen S partially extended from the right jamb, illustrated in a preferred embodiment of the invention.
[0039] FIG. 2 is a front view of the window of the FIG. 1 .
[0040] FIGS. 3, 4 , 5 , 6 and 7 are schematic perspective views of various operational modes of the double casement window of FIG. 1 .
[0041] FIG. 8 is a schematic side view of the operating positions for the detents with retractable pins of the window of FIG. 1 .
[0042] FIGS. 9 and 10 are schematic perspective views of operational modes of a single casement window containing two roll out assemblies illustrated in a preferred embodiment of the invention.
[0043] FIGS. 11 and 12 are schematic perspective views of operational modes of a single slider window with two roll out assemblies and illustrated in a preferred embodiment of the invention.
[0044] FIGS. 13 and 14 are schematic perspective views of operational modes of a double slider window with two roll out assemblies and illustrated in a preferred embodiment of the invention.
[0045] FIGS. 15, 16 and 17 are schematic perspective views of operational modes of a single hung window with two roll out assemblies and illustrated in a preferred embodiment of the invention.
[0046] FIGS. 18 and 19 are schematic perspective views of operational modes of a double hung window with two roll out assemblies and illustrated in a preferred embodiment of the invention.
[0047] FIGS. 20 and 21 are schematic perspective views of operational modes of an awning window with two vertically operating roll out assemblies and illustrated in a preferred embodiment of the invention.
[0048] FIGS. 22 and 23 are schematic perspective views of operational modes of a second awning window with two horizontally operating roll out assemblies and illustrated in a preferred embodiment of the invention.
[0049] FIGS. 24, 25 , 26 and 27 are schematic perspective views of operational modes of a replacement screen frame with roll out assemblies positions on each siding and illustrated in a preferred embodiment of the invention.
[0050] FIGS. 28, 29 and 30 are schematic perspective views of a French door assembly with the screen frame of FIG. 24 shown in various operational modes, and illustrated in a preferred embodiment of the invention.
[0051] FIGS. 31 and 32 are schematic perspective views of an entry door assembly with a screen frame similar to FIG. 24 .
[0052] FIG. 33 is a schematic perspective isolated view of the sill of the assembly of FIG. 31 illustrating detents locations which act as stop position for the draw bar of a roller assembly, and illustrated in one embodiment of the invention.
[0053] FIGS. 34 and 35 are schematic perspective views of a patio door assembly with a screen frame attachment incorporating rollout assemblies, and illustrated in a preferred embodiment of the invention.
[0054] FIG. 36 is an exploded view of a screen cassette as disclosed in U.S. Pat. No. 6,267,166.
[0055] FIG. 37 is an exploded view of a blind assembly, and the technique of fastening the blind material to the flexible “T” sections and illustrated in a preferred embodiment of the invention.
[0056] FIG. 38 is a partial perspective cut away view of a T-shaped edge of a screen/blind included with the roller assembly and illustrated in a preferred embodiment of the invention.
[0057] FIG. 39 is a partial cut away perspective view of a screen assembly with a T-shaped edge portion of FIG. 38 .
[0058] FIG. 40 is a schematic view of an installation of a screen for a retractable screen assembly illustrated in a preferred embodiment of the invention.
[0059] FIG. 41 is a perspective view of a blind, draw bar, and roller as assembled and illustrated in a preferred embodiment of the invention.
[0060] FIG. 42 is a perspective view of a screen cassette assembly, as previously illustrated and claimed in U.S. Pat. No. 6,267,168.
[0061] FIG. 43 is a cross section and perspective views of a jamb section with integral pocket construction as previously illustrated and claimed in U.S. Pat. No. 6,267,168.
[0062] FIG. 44 is a side view of a latch operator for the draw bar of a roller assembly and illustrated in a preferred embodiment of the invention.
[0063] FIG. 45 is a front view of latch operator for the draw bar of a roller assembly illustrated in a preferred embodiment of the invention.
[0064] FIG. 46 is a schematic perspective view of a replacement screen frame including four roll out assemblies, illustrated in one embodiment of the invention.
[0065] FIGS. 47 and 48 are schematic perspective views of a double slider window carrying three roll out assemblies therein and, illustrated in one embodiment of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0066] Referring now to FIGS. 1 to 7 there is illustrated a double casement window assembly 500 including an outer frame containing a header 501 , a sill 502 , a right jamb 503 and a left jamb 504 . Additionally the assembly contains two sashes, left and right, including sash frame members 507 , 508 , 509 and 510 for the left sash and sash frame members 507 ′, 508 ′, 509 ′, and 510 ′ for the right sash. Each sash has a locking device 506 and 506 ′ best depicted on FIG. 3 . Left jamb 504 has a pocket P best illustrated in FIG. 43 which contains roll cassette 511 also illustrated in FIG. 42 . The right jamb 503 includes a pocket with a roll cassette 511 ′ which contains a blind S′ made of plastic or alternative equivalent materials.
[0067] Both sill 501 and header 502 of the window frame include tracks T to guide the rollout assembly movement as best seen in on FIG. 3 . Each track T in the header 502 and the sill 501 contains multiple detents D that allow locking of rollout assemblies at predetermined positions inside the window frame. Each detent D is a cut out positioned at each track T.
[0068] Referring now to FIG. 1 there is illustrated an operating position for the rollout assemblies. The bug screens S is extended from the screen cassette 511 to the mullion 505 of the window 500 while the blind S′ is extended from the blind cassette 511 ′ to the mullion 505 of the window whereat a bug seal 515 exists between the two draw bars 512 and 512 ′.
[0069] Referring now to FIG. 3 the bug screen S is fully retracted into the screen cassette 511 while the roll out blind S′ is fully retracted into its screen cassette 511 ′, allowing the windows to be opened prior to extending either the bug screen or the blind.
[0070] Referring now to FIG. 4 the blind S′ has been fully retracted into blind cassette 511 ′ while the bug screen S remains fully extended from the screen cassette 511 , contained in the pockets for the left jamb 504 and the right jamb 503 respectively.
[0071] Referring now to FIG. 5 the bug screen S is fully retracted into the screen cassette 511 contained inside the pocket of the left jamb 504 , while the blind S′ remains partially extended from the blind cassette 511 ′ contained in the pocket of the right jamb 503 . The blind is locked in an intermediate position by engaging the draw bar 512 ′ with the detents as will be described hereinafter.
[0072] Referring now to FIG. 6 the blind S′ is further extended from the position illustrated in FIG. 5 . Here the blind S′ is covering about ¾ of the window frame while the bug screen S is fully retracted into the screen cassette 511 .
[0073] Referring to FIG. 7 the blind S′ is fully extended from the cassette 511 ′ towards the left jamb 504 of the window 500 , fully covering the window with by the plastic blind S′. By installing two cassettes 511 and 511 ′ and strategically placing detents along the tracks of the rollout screens, the screen S and blind S′ for double casement window may be placed in various modes namely; uncovered as seen in FIG. 3 , fully covered by bug screen S as seen in FIG. 4 , half protected by bug screen S and half covered by blind S′ as seen in FIG. 1 , partially covered by the blind S′ as seen in FIGS. 5 , and 6 and finally fully covered by the blind S′ as illustrated in FIG. 7 . These various modes for the screen consider and blind cassette equally apply to all types of closure assemblies illustrated herein.
[0074] Referring to FIG. 8 there is illustrated a schematic side cut out view of a latch assembly 512 including release members 518 . Position (I) in FIG. 8 illustrates the retractable pin 518 being released from the detent D, whereat draw bar 512 is free to move along the track T. Position (II) in FIG. 8 illustrates the retractable pin 518 engaged with the detent D whereat in this position draw bar 512 is locked and restricted from any movement. By operation of the latch operator 514 and retracting the pin 518 as shown in position I the homeowner may pull the draw bar handle 513 to permit the roll out screen to extend from the screen cassette. Subsequently the latch operator 514 may be released resulting in, the retractable pin 518 engaging with one of the multiple detents D then preventing any further movement of the draw bar until the further operation of the latch operator 514 .
[0075] Referring now to FIGS. 9 and 10 there is illustrated the single casement window 520 that includes an outer frame which consists of header 521 and sill 522 , right jamb 523 and left jamb 524 . Further the assembly includes a sash contained within the outer frame including frame members 527 , 528 , 529 and 530 . The sash includes a sash locking device 526 . Left jamb 524 include a pocket P containing screen cassette 531 which carries a bug screen S while the right jamb 521 has a pocket that contains a blind cassette 531 ′. Both the header 521 and the sill 522 include tracks T that allow motion of rollout screen/blind horizontally from the left jamb to right and also from right jamb to the left. The tracks T contain detents D (preferably cutouts) that allows for engagement of the draw bars 532 and 532 ′ at predetermined positions along the track T.
[0076] Referring now to FIG. 9 the bug screen S is fully extended from the screen cassette 531 to the opposite jamb 523 . There is a bug seal 535 provided on the vertical edge of draw bars 532 and 532 ′ to seal these edges when the rollout assemblies are position in close proximity, whereat the bug seals are engaged.
[0077] In the same manner as described in relation to FIGS. 1-7 , there are various operational positions for the rollout screen/blind which can also be used with a single casement window from fully retracted to fully extended positions. In FIG. 10 the bug screen S is fully retracted into the cassette 531 while plastic blind S′ is partially extended from blind cassette 531 ′ and engaged one of in the detents D along the track T.
[0078] Referring to FIGS. 11, 12 , 13 and 14 there are illustrated single and double tilt and slide windows respectively. In FIGS. 11 and 12 there is illustrated a single tilt and and slide window wherein only one sash is moveable within the other sash being stationary. In FIGS. 13 and 14 there is illustrated a double tilted slide window moveable. The window assembly 540 includes an outer frame portion which consists of header 541 , sill 542 , right jamb 543 and left jamb 544 . Left jamb 544 has a pocket P containing screen cassette 551 while opposite jamb 543 has a pocket P containing a screen cassette 531 ′ with the rollout bug screen S. The window assembly has two sashes one moveable in the front of the another stationary sash is known in the art. The front sash as best seen in FIG. 11 consists of frame members 547 , 548 , 549 , 550 and has an operating handle 545 . This sash is moveable from a fully closed position as is illustrated in FIG. 11 , to fully open position as illustrated in FIG. 12 . As in FIGS. 1 to 7 header 541 and sill 542 parts of the outer frame contains tracks T for the movement of the draw bars 552 , 552 ′ of screens S and S′ and engaged thereof within multiple detents D provided in the tracks T. The roll out blind S′ extends from a fully retracted position inside left jamb 544 to fully extended position beside right jamb 543 . Alternatively the blind S′ may be stopped in any of the detent locations shown. Likewise the bug screen S can be extended from the screen cassette 551 ′ disposed inside the pocket of right jamb 543 to a fully extended position. The window illustrated in FIGS. 11, 12 , 13 and 14 include a moveable sash having frame members 556 , 557 , 558 and 559 . Both front and back sashes may be locked in position by the operation of cam lock 546 as best seen in FIG. 14 .
[0079] FIGS. 15, 16 and 17 illustrate a single hung window embodying the invention while FIGS. 18 and 19 illustrate a double hung window embodying the invention. Each window 560 has an outer frame consisting of header 561 , sill 562 , right jamb 563 and left jamb 564 and includes two sashes, a front sash with frame members 567 , 568 , 569 and 570 and a back sash with frame members 576 , 577 , 578 and 579 . In FIGS. 15, 16 and 17 the back sash is stationary while in FIGS. 18 and 19 the back sash is also moveable.
[0080] Referring now to FIG. 16 it is clear that tracks T are located on the right jamb 563 and left jamb 564 . Further pockets P containing screen/blind cassettes 571 and 571 ′ are located in the header 561 and sill 562 . The blind S′ extends from the screen cassette 571 ′ by operating the draw bar 572 ′, by means of handle 573 ′, from a fully retracted position shown in FIG. 16 to a partially extended position illustrated in FIGS. 15 , and 17 . The bug screen S is engaged with the front sash by the means of a latch operator 574 . The screen S or S′ extends from a fully retracted position as illustrated in FIG. 16 to a fully extended position shown in FIG. 15 .
[0081] Now referring to FIG. 18 both sashes are moveable up and down in relation to one another once unlocked by the means of a sash handle such as 565 ′. The two sashes may be locked by the cam lock 566 . FIG. 19 illustrates bug screen S extending from screen cassette 571 and connected to sill 568 , when the sash is fully open and the blind S′ is fully retracted into the screen cassette 571 ′.
[0082] Referring to FIGS. 20, 21 , 22 and 23 there is illustrated an awning window in various embodiments of the invention. FIGS. 20 and 21 illustrate rollout assemblies moveable in vertical directions from the top and bottom portions of the window whilst FIGS. 22 and 23 depict windows while rollout assembly movable in horizontal directions.
[0083] Referring to FIG. 20 window assembly 580 has an outer frame which includes header 581 , sill 582 , right jamb 583 and left jamb 584 and a sash including frame members 587 , 588 , 589 , 590 and a pair of brackets 596 which allows pivoting of the sash from the window frame. The sash lock 586 and the sash handle 585 are best illustrated in FIG. 22 , to move the window from a locked position to an open pivoted position.
[0084] Referring now to FIG. 20 sill 582 has a pocket P that contains screen cassette 591 with the bug screen S. FIG. 20 illustrates bug screen S fully extended from the cassette 591 to the header 581 of the window where it is engaged by draw bar 592 ′. In this embodiment of the invention the tracks T are located on the right and left jambs 583 and 584 of the awning window. These tracks T have multiple detents D which provide multiple stops for the blind or screen.
[0085] Referring to FIG. 21 bug screen S is fully retracted into cassette 591 while the blind S′ is partially extended from its cassette 59 ′ toward the bottom part of the window. As in previous embodiments there are number of multiple positions for both rollout assemblies S and S′ forfully extended, fully retracted, and partially extended positions whereat track detents are engaged. Both draw bars 592 and 592 ′ are equipped with draw bar handles 593 and 593 ′ and latch operators 594 and 594 ′ which allows the engagement of the draw bar pins with the detents D of the tracks #. On the leading edge of each draw bar there are provided bug seals 595 which contact one another when the draw bars engage. In the alternative embodiments of the invention illustrated in FIGS. 22 and 23 the pockets with the cassettes are located in the left jamb 584 and right jamb 583 of the assembly and the tracks T including detents D are located in the header and sill parts of the window frame 581 and 582 .
[0086] FIGS. 24, 25 , 26 and 27 illustrate a replacement screen frame assembly. Therefore the assembly 600 has a top frame member 601 a bottom frame member 602 , a right housing 603 and left housing 604 . Housing 603 contains a rollout bug screen assembly S and the housing 604 contains a rollout blind assembly S′. The bug screen assembly S illustrated in FIG. 25 includes a draw bar 605 , draw bar handle 606 and a latch operator 607 . It also contains a bug seal 608 on the leading edge of the draw bar and additional stoppers 609 that prevent jamming of the draw bar inside the cassette housing 603 when retracted. The top and the bottom frame members shown in FIG. 24 include tracks T for the movement of rollout assemblies including multiple detents D providing predetermined stop positions for the rollout assemblies. As mentioned previously the roll out assemblies operates in various modes, for example; a fully retracted position as illustrated in FIG. 24 , a partially extended position near the central part of the screen frame as illustrated in FIG. 25 . The bug screen S is shown fully extended from the cassette 603 adjacent the housing part 604 as best seen in FIG. 26 . Blind S′ is fully extended from the housing 604 adjacent the housing 603 as best seen in FIG. 27 . In this position the bug screen S is fully retracted into the housing 603 . Either rollout assembly might be operated to and from an intermediate position along the track of the screen frame assembly. The engagement with track T of the rollout assemblies at various positions along the tracks functions in the same manner as described and illustrated in relations to FIG. 8 .
[0087] An assembly for replacement screen frames might be installed with previously described closure assemblies such as doors or windows. The following are examples for the use of such a screen frame embodied with various door assemblies such as a French door, an entry door and a patio door. These examples are illustrative only and are not to be considered as limiting the scope of the invention.
[0088] In FIGS. 28, 29 , and 30 a replacement or add on screen assembly is illustrated attached to the frame of a French door assembly. The French door assembly contains an inside frame which consists of a header 611 , seal 612 , right frame member 613 and left frame member 614 . The screen frame previously illustrated in FIGS. 24 to 27 , is shown attached to the inside surface of the French door assembly frame. In a similar manner to the embodiment with a window assembly, the screen frame attached to the French door assembly may operate in various modes. For example, FIG. 28 shows a partial extension of the blind S′ from the left housing to the center of the assembly with the bug screen S being partially extended from the right housing 603 to the center of the assembly. FIG. 29 illustrates the bug screen S fully extended from the housing 603 to the left side of the door assembly. FIG. 30 illustrates partial extension of the blind S′ from the housing.
[0089] In yet another embodiment of the invention, the screen frame may be attached to the entry door assembly as shown in FIG. 31 . FIGS. 31 and 32 therefore illustrate an entry door with an add onscreen assembly similar to the French door embodiment. The add on screen assembly is thereof attached to an entry door frame containing header 611 , seal 612 , right frame member 613 and left frame member 614 and entry door 615 . FIG. 33 illustrates the detents D positioned on the bottom frame member of the screenless screen. Again as in previous embodiments the add on screen frame assembly operates in various modes. For example in FIG. 31 the screen is fully extended from the housing 603 toward the left part of the assembly and in the FIG. 32 , both rollout assemblies are partially extended from the housing.
[0090] In the same manner, replacement or add on screen assemblies may be attached to a patio door assembly as illustrated in FIGS. 34 and 35 . The door frame assembly illustrated includes top frame member 611 , bottom frame member 612 , right frame member 613 and left frame member 614 having attached there to a replacement or add-on screen assembly as described in relation to FIGS. 24 to 27 . FIG. 34 illustrates the use of an add-on or replacement screen assembly with a bug screen S extending from the housing part 602 toward the center of the assembly and the blind S′ extended from the housing 603 toward the center of the assembly. FIG. 35 illustrates the bug screen S fully retracted into the housing 604 and blind S′ partially extended from the housing 603 .
[0091] FIG. 36 , illustrates an exploded view of a screen cassette assembly including a jamb with an integral pocket and associated parts from the header and the sill as taught in Applicant's prior patents namely U.S. Pat. No. 6,267,168 hereby in corporation by reference. However the draw bar of the current invention is different from the one illustrated in the FIG. 36 wherein parts 350 ′- 340 ′- 330 ′- 320 ′ are replaced by a new draw bar and latch operator with retractable pins shown in FIGS. 42, 44 and 45 .
[0092] FIG. 37 illustrates the assembly 640 of the blind S′ with the T-shape keys 643 , 645 as described in Applicant's prior patent abovementioned hereby incorporated by reference. The T-shaped keys at the end of the blind material engage with the T-shaped cavities 649 , 648 of the draw bar 641 and the roller 642 . As is apparent from FIG. 37 the T-shaped keys are attached to the blind material in the following manner. The blind material S′ has numerous perforations along its sides, which perforation are inserted between the key members 643 and a supplementary portion 644 . The blind material may be optionally perforated. However it may be attached without perforations as well. These plastic members 643 , 644 and blind S′ are attached by means of known welding techniques, by the application of heat or any other method known to persons skilled in the art. In this way the T-shaped keys are attached to any type of blind S′ regardless the type of the material.
[0093] FIG. 38 illustrates the preferred T-shaped key attached to the edge of blind S′ and FIG. 39 illustrates the preferred T-shaped key attached to the bug screens. Other key shapes are also possible as taught in Applicant's prior patent abovementioned.
[0094] FIG. 40 shows how the T-shaped key members 645 and 643 fit into the T-shaped cavities 648 and 649 in the roller drum 642 and in the draw bar assembly 641 . FIG. 41 illustrates screen S′ fully attached to the roller drum and the draw bar as previously taught in Applicant's prior patent abovementioned.
[0095] FIG. 42 illustrates screen cassette assembly 511 with partially extended blind S′. It is easy to see that draw bar 512 has a bug seal 515 , handle 513 which may include a guide members 517 which guides the rollout assembly along the tracks. In addition, draw bar 512 include a latch operator 514 which controls the retractable pins 518 on the opposite ends of the draw bar. The latch operator is fully described in Applicants provisional application No. 60/689,068 incorporated herein by reference and from which this Application claims priority. The blind S′ is attached to the draw bar 512 as explained above in relation FIGS. 37-41 , by the same means blind S′ is attached to the roller which is mounted on brackets 519 and 519 ′ for installation in the jamb pockets. These brackets allows accurate installation of the screen cassette into the pocket inside the jamb illustrated in FIG. 43 without additional fastening means.
[0096] FIG. 43 illustrates the profile of the jamb 503 and the details thereof with the pocket P as described in FIGS. 1-7 , 9 - 23 . Following the installation of the screen cassette 511 into the pocket P, brackets 519 and 519 ′ engage with the surfaces of the interior of the pocket P, allowing the roll out assembly S or S′ to extend from the cassette when pulling the draw bar handle to the required operating position, while the brackets are prevented from moving as taught in Applicant's prior patent abovementioned.
[0097] FIGS. 44 and 45 illustrate side and front view of the latch mechanism described in Applicant's prior application No. 60/689,068 incorporated herein by reference and from which priority is claimed. The retractable square pins 518 , presented in one of numerous geometrical forms such as square, cylinder, or triangular for example, are activated by the latch operator 514 . As best seen on FIG. 45 , by the mean of horizontal motion of the latch operator 514 pulls the pins 518 into the draw bar assembly allowing the draw bar to move along the track T. This assembly is taught in Applicant's prior priority Application abovementioned. Releasing of the latch operator 514 , the spring member 516 extends, and releases the pins 518 of the draw bar, so as to engage with one of the multiple detents D located along the tracks T as was previously disclosed above.
[0098] Referring to FIG. 46 , there illustrated an alternative embodiment of the invention including up to four roll out assemblies embodied into one add on or replacement screen assembly. Such an assembly if desired may be incorporated onto the frame of an existing window assembly or attached to the frame of a patio door assembly in the same way as has been previously described for add on and replacement screen. This assembly includes a top frame member 621 and a bottom frame member 622 . In this case the frame includes two cassette housings on each side. For the front right side a housing and cassette 624 are provided and at the back housing 623 as well. At the left side housing cassettes 625 and 626 are also provided at the back and front as well.
[0099] Also shown in FIG. 46 are rollout assemblies extending from housings 624 and 625 in a fully retracted position while the rollout screen from the housing 623 , with the draw bar 628 , is fully extended from the right side to the left and rollout screen assembly from the housing 626 with draw bar 629 , is partially extended to the right. This assembly is not a limiting one and it may for example include one bug screen in the cassette housing 623 , a solar screen in cassette housing, 625 and two blinds within cassette housings 626 and 624 , or other alternatives as desired.
[0100] Referring now to FIGS. 47 and 48 there illustrated an alternative embodiment of the invention for a tilted slide window two moveable sashes incorporating three rollout assemblies therein. This assembly resembles the embodiments of FIGS. 13 and 14 with an additional track T′ disposed in the sill and the header behind the sashes, and an additional pocket for a screen cassette located in the left jamb 544 . The third solar screen S″ is best seen in FIG. 48 with both sashes in a tilted and opened position.
[0101] It is important to note that each cassette is sized so as to be received in a pocket for the various embodiments of the invention. Thus the cassettes are interchangeable in position for the homeowners' convenience. Replacement cassettes are also readily available.
[0102] As many changes can be made to the preferred embodiments of the invention without departing from the scope thereof. It is intended that all matter contained herein be considered illustrated of the invention and not in a limiting sense. | A closure assembly to be installed in an opening for a building, said closure assembly comprising a frame for supporting a moveable closure member therewithin, said frame including top, bottom and side members, one of the members including a hollow pocket within the interior of said member and for receiving a spring biased roller assembly upon which a flexible material is accumulated, said flexible material being selected from a blind, a bug screen, a solar screen, or the like, the flexible material being movable between a fully retracted first position whereat the material is contained within the pocket to a fully extended second position whereat the material covers some or all of the opening of the building. | 4 |
This application claims benefit of priority date of provisional application, Ser. No. 60/284,995 filed Apr. 19, 2001.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates in general to railcars and, in particular, to an improved railroad passenger seat.
2. Summary of the Invention
Numerous designs for railcar passenger seats have been employed over the long history of railroads. A walkover seat is commonly used in current passenger car applications because the seat back position can be moved to oppositely facing directions. Known walkover seats suffer from several problems involving economy of design and manufacture, safety, maintenance and durability. From the safety standpoint, the presence of an unrestrained or restrained seat in front of a passenger creates a hazard during rapid deceleration, such as during a catastrophic emergency. The unrestrained seat offers no protection and causes serious injuries when impacted by a passenger during deceleration. Restrained seats, such as by means of latches and the like, form a rigid obstacle, which likewise causes injury to the passenger impacting the seat back during deceleration. Attempts have been made in the prior art to absorb the energy of impact by a passenger against a seat back, but a need exists in providing effective and economical means of protecting the passenger during emergency situations.
In its opposing positions, the seat back of prior devices utilize latches, stops and support brackets to retain the seat back. Such retention elements are subject to unnecessary wear and require periodic adjustment. Further, the use of brackets and the like to retain the seat back upright does not provide optimum strength characteristics. The seat frames in the past have further used latches or locks to retain it in an operable position. Such latches or locks are subject to stress, which requires repair or replacement. In moving the walkover seat back, the latches can be noisy and are not passenger friendly. The design of seat cushion of prior walkover seats further do not have a frame and cushion design which maximizes the ease of installation by being easily self-positioning. In addition, prior seat cushions do not optimize protection to the cushion by preventing damage from retention clips, vandalism, and normal everyday use. Therefore, it is desirable in the prior art to provide an improved passenger seat overcoming the foregoing and other problems in the prior art.
SUMMARY OF THE INVENTION
It is, therefore, an objective of the invention to provide an improved walkover sat for passenger railcars. The invention hereto provides a seat design of superior strength with a low weight ratio and smooth operative characteristics. The walkover seat of the application is easy to install and service. The cushion frame is designed to rest directly on the seat frame in opposite positions to eliminate the need of latches or locks for retention. By resting on the seat frame, stress on the seat linkages is substantially reduced and a more lightweight linkage assembly can be employed. Such support of the seat cushion frame further provides a stable, quiet, and passenger friendly seat design and is self-positioning.
The seat back of the invention is mounted for movement on a pair of self-positioning levers on each side. In the opposite seat positions, the levers abut each other to retain the seat back in its upright positions. The abutting levers eliminate the need to use support brackets, stops and the like. The abutting levers further provide greater longevity of service, eliminate wear and do not require costly adjustment. The levers also provide excellent strength when stressed to provide a good strength to weight ratio.
The seat cushion of the invention is provided with a unique bottom pan, which protects the seat cushion against damage from installation and use. The cushion pan allows the seat cushion to be dropped onto attachment elements for easy installation and has no exterior protrusions to damage other cushions during transport and use.
The invention herein further is provided with dual locks at opposite ends of the shafts carrying the walkover seat back levers. The dual locks are mounted in end blocks, which also contain energy dissipation shafts. The energy dissipation shafts cooperate with the locks in the blocks to dissipate energy upon the locks restraining rotation of the walkover shafts during extraordinary deceleration conditions of the railcar. The end blocks simplify the elastic components and reduce associated costs and weight.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front perspective view of a passenger seat employing the improvements of the invention;
FIG. 2 is a partial side elevational view of the seat back frame and linkage assembly of the passenger seat of the invention viewing outward of the seat;
FIG. 3 is a partial side elevational view of seat back frame and linkage assembly of the passenger seat of FIG. 2 showing the seat back in a first seating position;
FIG. 4 is a partial side elevational view of the seat back frame and linkage assembly of FIG. 2 in an intermediate position;
FIG. 5 is a partial side elevational view of the sat back frame and linkage assembly of FIG. 2 in an opposite seating position from FIG. 3;
FIG. 6 is a partial end perspective side view, with parts in phantom, of the locking block of the passenger seat of the invention showing the locking element in a locked configuration;
FIG. 7 is a partial top perspective view of the locking block and torsion shaft of the invention showing the locking element in an unlocked seating position; and
FIG. 8 is a side perspective view, with parts exploded, of the cushion frame and cushion of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIGS. 1 to 10 , there is illustrated the improved walkover seat of the invention, generally designated by reference numeral 2 . Although the seat 2 is described herein as a walkover seat for passenger railroad cars, it is within the scope of the invention to use the teachings of the invention in any environment in which passenger seats are employed. As is conventional, the passenger walkover seat 2 includes a horizontal seat cushion 4 and a walkover seat back 6 supported on a seat frame 8 , which rests on suitable opposed pedestals (not shown). The walkover feature of seat 2 allows the conductor or passenger to move the seat back 6 to opposed positions relative to seat 4 whereby the passengers face in opposite directions.
The walkover capability of passenger walkover seat 2 is best shown in FIGS. 2-4. The seat walkover mechanism 12 is provided with a pair of flat walkover levers 14 and 16 . The walkover levers 14 and 16 are interconnected at their upper ends 14 a and 16 a by a link 18 pivotally attached to the lever ends by pins 19 . A seat back frame member 20 is attached to the upper portion 18 a of link 18 by a suitable technique to attain walkover movement of seat back frame member 20 on the levers 14 and 16 in conjunction with a pair of horizontal walkover tubes 22 and 24 . The walkover tubes 22 and 24 are suitably journaled at both ends on frame 8 and extend through the lower ends of levers 14 and 16 in fixed relationship and under the seat cushion 4 from the aisle side to the window side of passenger seat 2 . The opposed positions of the walkover levers 14 and 16 are shown in opposite positions of the seat back 6 in FIGS. 3 and 5. During walkover movement from the position of FIG. 3 to the position of FIG. 5, the walkover tubes 22 and 24 rotate in the same directions to facilitate movement of the entire seat back 6 to the opposed position.
Referring now to FIGS. 6 and 7, a locking block assembly 30 is mounted at each end of hollow walkover shafts 22 and 24 immediately inside of seat back frame levers 14 and 16 . The locking block assembly 30 includes a metal block 30 a having rear integral anchoring plate 32 which is arranged to be secured to frame 8 at both sides by bolt assemblies (not shown) through bolt holes 32 a . A front plate 34 (FIG. 7) is also secured to block 30 a by bolts 36 to mount the linkage assembly to be described. The block 30 a has a cavity 38 to permit solid end extensions 40 a , 40 b to be secured to the ends of walkover tubes 22 and 24 and extend through levers 14 and 16 in fixed securement by a conventional technique. The inner ends 42 of the end extensions 40 a , 40 b have flattened faces 44 for interfitting in fixed relationship respectively within the ends of hollow walkover shafts 22 , 24 having a hollow square cross-sectional configuration.
A locking element 50 is journaled between end extensions shafts 40 a , 40 b for pivotal movement on a shaft 50 a carried on locking block 30 a as seen in FIGS. 6 and 7. The locking element 50 is generally in the form of a rectangular plate having opposed cutout areas 52 disposed on opposite vertical sides of the locking element 50 and cut-off upper corners 54 . The lower portion 56 of locking element 50 extends a greater distance from the shaft 50 a than upper portion 56 a to create an imbalance to respond to deceleration and cause pivoting action of the locking element 50 about shaft 50 a dependent on the direction of the deceleration forces. In a normal vertical orientation of the locking element 50 in absence of any extraordinary forces, the walkover tubes 22 , 24 and end extensions 40 a , 40 b are free to rotate to change seat back positions. The end extension shafts 40 a and 40 b are formed with locking notches 52 a , 52 b in the periphery at two positions on each end extension shaft 40 a , 40 b . The cutout areas 52 a , 52 b are formed by two intersecting faces 54 a , 54 b whereby one face 52 a extends parallel to the axis of rotation of end extensions 40 a , 40 b.
In FIG. 6, the locking effect of the locking elements 50 and the cutout areas 52 a , 52 b can be seen. In the case of rapid deceleration, the walkover tubes 22 , 24 are rotated in opposite directions for a limited degree until the surface of a cutoff corner of the lock element 54 a engages a portion of the flat face 56 a of the end extension 40 a , 40 b at the same time the locking elements 50 contacts a respective cutout area 52 a , 52 b and the upper corner contacts the notches 52 a , 52 b of the opposite shaft. The deceleration detected by the locking element 50 is rapid in locking rotation of the walkover shafts 22 and 24 to prevent any further movement of the seat back. After the locking has occurred between the locking element 50 and walkover tubes 22 , 24 , the energy dissipation sections 60 a , 60 b formed by the thinner diameter of the end extensions 40 a , 40 b then undergo conditions of plastic deformation by which permanent twisting of the reduced diameter section occurs to the extent necessary to arrest and dissipate the force of the impact. The energy dissipation sections 60 a , 60 b can under go up to 90° of permanent deformation under which twisting optimum energy dissipation of the impact force of the passenger with the seat back occurs because the time in dissipating the energy is significantly increased by the plastic deformation.
The levers 14 , 16 are fixedly retained on the lower ends 14 b , 16 b to end portions of walkover tube extensions 40 a , 40 b . The pair of levers 14 , 16 are mounted at each shaft end in a common vertical plane. In the normal opposed seating positions of the seat backs, the adjacent edges 14 ′, 16 ′ of the levers 16 directly abut each other (FIGS. 2, 3 and 5 ) to support the seat back with a high strength to strength ratio. Such direct support eliminates the stops and brackets needed in the prior art and provides good strength in the stressed direction. As seen in FIG. 4, the adjacent edges of the levers are spaced from each other in the intermediate position. As seen in FIGS. 2-5, a pair of linkage assemblies 70 a , 70 b are further provided in operative relationship between the walkover tubes 22 and 24 and the lower seat cushion frame 72 . The cushion frame 72 includes a horizontal pair of elongated edge cross frame members 74 interconnected by end members 76 (FIGS. 8 and 9 ). A pair of intermediate supports 78 further extend between the end members 76 . The pair of linkage assemblies 70 a , 70 b move the seat back frame 20 from the position shown in FIG. 3 to the position shown in FIG. 5 . In is normal opposed seating portions, the upper surface 80 of the end members 74 are slightly sloped downward from the seat front to the walkover seat back as seen in FIGS. 3 and 5. Each of the linkage assemblies 70 a, 70 b are operatively connected to a respective walkover tube 22 , 24 by a pair of oppositely facing pivot arms 82 a, 82 b which are affixed at one end to tube extensions 40 a, 40 b.
The opposite ends of the pair of pivot arms 82 a, 82 b include a pin 86 which extends into an elongated slot 88 formed along a straight longitudinal axis in elements 90 of each of the pair of linkage assemblies 70 a, 70 b. The link elements 90 are flat members having a modified “L” shape with a pair of straight edge portions 92 and a curved interconnecting portion 94 (FIG. 2 ). Each link element 90 is pivotally connected to the cushion frame end members 76 at a point adjacent the intersection of the straight edge portions 92 and curved portion 94 of the link elements 90 . As the walkover seat back is moved between opposed seating positions, the pin 86 of the lever element 90 moves in the slots 88 in opposite directions of the respective link members. At the upright position during initial movement of the seat back, the respective pins 92 move to opposite ends of the slots 94 . As the seat back continues movement to opposite seat positions, the link elements 90 continue pivotal movement and alter the position of the seat cushion frame 72 . In the position of seat cushion frame 72 in FIG. 3, the frame member 74 of the seat cushion frame 72 directly rests on cross horizontal member 90 a of the main seat frame in direct supporting contact along the width of the seat. One of the intermediate frame member 78 of the cushion frame 72 also directly contacts a second horizontal member 92 a of the main seat frame. For better support both the cushion frame members 74 and main frame members 90 a, 92 b advantageously possess a square configuration. Such direct contact between the cushion frame 72 and main frame cross members 90 a, 92 b provides maximum support of the seat cushion frame and seat back without latches or locks.
When walkover seat 2 is moved to the seating position of FIG. 5, the opposite cushion cross frame 74 directly contacts the main seat cross frame 92 a . The second intermediate cross frame 78 rests on the opposite seat main frame 90 a in FIG. 5 . At the seat back position of FIG. 3, the lever arms 82 a , 82 b are disposed along generally parallel planes with the lever arms 82 a , 82 b directed upward and the free end of the lever arm 82 b is directed downward. In the seat back position of FIG. 5, the pin end of the pivot arms 82 a is directed downward and the pin end of the pivot arm 82 b is directed upward in generally parallel relationship. In the intermediate position of FIG. 5, the pin ends of lever arms 82 a , 82 b are generally directed in opposite directions along the same horizontal axis.
Referring to FIG. 10, there is illustrated the bottom of a seat cushion 100 prior to attachment to the seat cushion frame 72 . The bottom of seat cushion 100 includes a pan 102 in the form of a metal or plastic that covers the bottom of the seat cushion 100 for protection. The pan 102 includes a pair of rectangular openings 104 and is secured to the seat cushion by mechanical fasteners (not shown). A series of strips 106 of hooks or loops of material, such as sold under the trademark VELCRO hooks are secured along the front and rear portions of the pan 102 . Complimentary strips 108 of loops, which adhere to strips 106 , are secured by an adhesive to cushion frame members 74 , whereby the cushion 100 is simply installed by being placed on the seat cushion frame 72 with strips 106 and 108 in contact. Such a securement capability results in immediate self positioning of the cushion on the seat frame and permits ready removal of the cushion 100 for repair and replacement. | A passenger seat having a walk-over seat back mounted for movement on a pair of rotatable shafts through a pair of of levers mounted on each end of the shafts. The levers contact each other at opposite seat positions to support the seat back. The pair of shafts include a torsion section at each end portion capable of undergoing plastic deformation upon a lock mechanism detecting predetermined deceleration forces. A lever and link element are operatively connected between the seat cushion frame to permit movement. The seat cushion is removable secured to the seat cushion frame. | 1 |
BACKGROUND OF THE INVENTION
The present invention relates to a cylinder recongnition apparatus for a multi-cylinder internal combustion engine which can recognize the operating condition or rotational position of each engine cylinder based on the output signals from a signal generator.
In order for a multi-cylinder internal combustion engine to properly operate, fuel injection, ignition and the like for each cylinder must take place at prescribed rotational positions or angles of the crankshaft of the engine, i.e., at the times when each piston of the engine is at prescribed positions with respect to top dead center. For this reason, an engine is equipped with a rotational position sensor such as a signal generator which senses the rotational angle or position of the crankshaft of the engine.
FIG. 4 illustrates, in a block diagram, a conventional cylinder recognition apparatus for a multi-cylinder internal combustion engine. The cylinder recognition apparatus includes a signal generator 8 which generates a positional signal L including a plurality of positional pulses corresponding to the respective cylinders of the engine, an interface circuit 9, and a microcomputer 10 which receives the positional signal L from the signal generator 8 through the interface circuit 9 and recognizes, based thereon, the operating condition (i.e., crank angle or rotational position) of each cylinder.
A typical example of such a signal generator 8 is illustrated in FIG. 5. In this figure, the signal generator 8 illustrated includes a rotating plate 2 mounted on a rotating shaft 1 (such as the distributor shaft) which rotates in synchrony with the crankshaft of the engine. The rotating plate 2 has a set of first slits 3a formed in it at prescribed locations. The slits 3a are disposed at equal intervals in the circumferential direction of the rotating plate 2. The slits 3a, which are equal in number to the cylinders, are disposed so as to correspond to prescribed rotational angles of the crankshaft and thus to prescribed positions of each piston with respect to top dead center for sensing when the crankshaft reaches a prescribed rotational position for each cylinder. Another or second slit 3b is formed in the rotating plate 2 adjacent one of the first slits 3a at a location radially inwardly thereof for sensing when the crankshaft rotational angle is such that the piston of a specific reference cylinder is in a prescribed position.
A first and a second light emitting diode 4a, 4b are disposed on one side of the rotating plate 2 on a first outer circle and a second inner circle, respectively, on which the outer slits 3a and the inner slits 3b are respectively disposed. A first and a second light sensor 5a, 5b each in the form of a photodiode are disposed on the other side of the rotating plate 2 in alignment with the first and the second light emitting diode 4a, 4b, respectively. The first light sensor 5a generates an output signal each time one of the outer slits 3a passes between the first light sensor 5a and the first light emitting diode 4a. Also, the second light sensor 5b generates an output signal each time the inner slit 3b passes between the second light sensor 5b and the second light emitting diode 4b. As shown in FIG. 6, the outputs of the first and second light sensors 5a, 5b are input to the input terminals of corresponding amplifiers 6a, 6b each of which has the output terminal coupled to the base of a corresponding output transistor 7a or 7b which has the open collector coupled to the interface circuit 9 (FIG. 4) and the emitter grounded.
Now, the operation of the above-described conventional cylinder recognition apparatus as illustrated in FIGS. 4 through 6 will be described in detail with particular reference to FIG. 7 which illustrates the waveforms of the output signals of the first and second light sensors 5a, 5b.
As the engine is operated to run, the rotating shaft 1 operatively connected with the crankshaft (not shown) is rotated together with the rotating plate 2 fixedly mounted thereon so that the first and second light sensors 5a, 5b of the signal generator 8 generate a first and a second signal L 1 , L 2 each in the form of a square pulse. The first signal L 1 is a crank angle signal called an SGT signal and has a rising edge corresponding to the leading edge of one of the outer slits 3a (i.e., a first prescribed crank angle or position of a corresponding piston) and a falling edge corresponding to the trailing edge thereof (i.e., a second prescribed crank angle of the corresponding piston). In the illustrated example, each square pulse of the SGT signal L 1 rises at the crank angle of 75 degrees before top dead center (a first reference position B75 degrees) of each piston, and falls at the crank angle of 5 degrees before top dead center (a second reference position B5 degrees).
The second signal L 2 is a cylinder recognition signal called an SGC signal, and has a rising edge corresponding to the leading edge of the inner slit 3b and a falling edge corresponding to the trailing edge thereof. The SGC signal L 2 is issued substantially simultaneously with the issuance of an SGT signal pulse corresponding to the specific reference cylinder #1 so as to identify the same. To this end, the inner slit 3b is designed such that it has a leading edge which corresponds to a crank angle before the first reference angle of the corresponding SGT signal pulse (i.e., a crank angle greater than 75 degrees before TDC), and a trailing edge corresponding to a crank angle after the second reference angle of the corresponding SGT signal pulse (i.e., a crank angle smaller than 5 degrees before TDC). Thus, actually, the rising edge of an SGC signal pulse occurs before that of a corresponding SGT signal pulse, and the falling edge of the SGC signal pulse occurs after that of the corresponding SGT signal pulse.
The two kinds of first and second signals L 1 , L 2 thus obtained are input via the interface circuit 9 to the microcomputer 10 which recognizes the specific reference cylinder #1 based on the second signal L 2 , and the operational positions (i.e., crank angles or rotational positions) of the remaining cylinders #2 through #4 based on the first signal L 1 , whereby various engine operations such as ignition timings, fuel injection timings, etc., are properly controlled.
With the conventional cylinder recognition apparatus for a multi-cylinder internal combustion engine as described above, however, two pairs of light emitting diodes 4a, 4b and light sensors 5a, 5b are required for generating two kinds of output signals L 1 , L 2 including the crank angle reference signal SGT and the cylinder recognition signal SGC. As a result, there arises the problem that the overall construction of the cylinder recognition apparatus becomes complicated, thus increasing the manufacturing cost thereof.
SUMMARY OF THE INVENTION
Accordingly, the present invention is intended to obviate the above-described problem of the conventional cylinder recognition apparatus.
An object of the present invention is to provide a novel and improved cylinder recognition apparatus for a multi-cylinder internal combustion engine which is able to recognize a specific cylinder as well as the remaining cylinders by use of only a single output signal of a signal generator.
Another object of the present invention is to provide a novel and improved cylinder recognition apparatus for a multi-cylinder internal combustion engine which is able to be manufactured at low costs.
A further object of the present invention is to provide a novel and improved signal generator suitable for use with a cylinder recognition apparatus which is simple in construction and which generates a single output signal including a plurality of first pulses each representative of prescribed rotational positions of a corresponding cylinder, and a second pulse for recognition of a specific cylinder.
In order to achieve the above objects, according to one aspect of the present invention, there is provided a cylinder recognition apparatus for a multi-cylinder internal combustion engine comprising:
a signal generator for generating a single output signal in synchrony with the rotation of the engine, the output signal including a plurality of positional pulses each representative of prescribed rotational positions of a corresponding cylinder, and a cylinder recognition pulse at a location near a specific one of the positional pulses corresponding to a specific cylinder; and
cylinder recognition means for discriminating the cylinder recognition pulse among the pulses contained in the output signal of the signal generator so as to recognize the specific positional pulse corresponding to the specific cylinder.
Preferably, the positional pulses in the signal generator output signal are square pulses having substantially the same pulse width, each of the positional signals having a rising and a falling edge which correspond to a first and a second rotational position, respectively, of a corresponding cylinder.
Preferably, the cylinder recognition pulse in the signal generator output signal is a square pulse having a rising edge and a falling edge, the cylinder recognition pulse having a pulse width less than that of the positional pulses.
In one embodiment, the cylinder recognition pulse in the signal generator output signal follows the specific positional pulse.
In another embodiment, the cylinder recognition pulse in the signal generator output signal precedes the specific positional pulse.
Preferably, the cylinder recognition means calculates the pulse width of each pulse in the signal generator output signal and the pulse interval between the rising or falling edges of successive pulses, calculates the ratio of the pulse width to the pulse interval for each pulse, and discriminates the cylinder recognition pulse based on the ratio thus obtained.
In one form, the cylinder recognition means calculates the pulse width t n of each pulse in the signal generator output signal and the pulse interval T n between the rising or falling edges of successive pulses, calculates the ratio (t/T) n of the pulse width t n to the pulse interval T n for each pulse and the difference between the present ratio (t/T) n for the present pulse and the preceding ratio (t/T) n-1 for the preceding pulse, compares the absolute value of the difference (t/T) n -(t/T) n-1 with a prescribed reference value α, and determines the present pulse to be the cylinder recognition pulse if (t/T) n -(t/T) n-1 >α.
The present ratio (t/T) n may be substituted for by the present ratio [t/(T-t)] n of the pulse width t n to the difference (T-t) n between the pulse interval T n and the pulse width t n for the present pulse, and the preceding ratio (t/T) n-1 may be substituted for by the preceding ratio [t/(T-t)] n-1 of the pulse width t n-1 to the difference (T-t) n-1 between the pulse interval T n-1 and the pulse width t n-1 for the preceding pulse.
In another form, the cylinder recognition means calculates the pulse width t n of each pulse in the signal generator output signal and the pulse interval T n between the rising or falling edges of successive pulses, calculates the ratio (t/T) n of the pulse width t n to the pulse interval T n for each pulse, compares the ratio (t/T) n with a prescribed reference value β, and determines a pulse to be the cylinder recognition pulse if the ratio (t/T) n for the pulse <β.
The ratio (t/T) n may be substituted for by the ratio [t/(T-t)] n of the pulse width t n to the difference (T-t) n between the pulse interval T n and the pulse width t n for each pulse.
According to another aspect of the present invention, there is provided a signal generator comprising:
a rotating shaft;
a rotating plate fixedly mounted on the rotating shaft and having a plurality of first slits and a second slit formed therein, the first and second slits being disposed on a circle around the axis of the rotating shaft, the first slits having substantially the same circumferential length and being circumferentially spaced from each other at substantially the same interval, the second slit being disposed near one of the first slits; and
a photocoupler disposed near the rotating plate for generating an output signal when it senses that one of the first and second slits in the rotating plate passes a prescribed location during the rotation of the rotating plate.
Preferably, the second slit has a circumferential length less than that of the first slits. The second slit may be disposed rearwardly or forwardly of the one of the first slits in a prescribed rotational direction of the rotating shaft.
The above and other objects, features and advantages of the present invention will become more readily apparent from the ensuing detailed description of a preferred embodiment of the invention taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view schematically illustrating the arrangement of a signal generator according to the present invention;
FIG. 2 is a waveform diagram of the output signal of the signal generator of FIG. 1;
FIG. 3 is a flow chart illustrating the operation of a cylinder recognition apparatus for a multi-cylinder internal combustion engine equipped with the signal generator of FIG. 1 according to the present invention;
FIG. 4 is a schematic block diagram of a conventional cylinder recognition apparatus for a multi-cylinder internal combustion engine;
FIG. 5 is a perspective view illustrating the general arrangement of a conventional signal generator employed with the conventional cylinder recognition apparatus of FIG. 4;
FIG. 6 is a schematic circuit diagram of the conventional signal generator of FIG. 5; and
FIG. 7 is a waveform diagram of a crank angle reference signal L 1 and a cylinder recognition signal L 2 .
DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention will now be described in detail with reference to a preferred embodiment as illustrated in the accompanying drawings.
First, it should be understood that the general arrangement of a cylinder recognition apparatus for a multi-cylinder internal combustion is similar to that of the conventional one illustrated in FIG. 4. However, a signal generator, which is generally designated by reference numeral 108 in FIG. 1, is different in construction and operation from the conventional one as illustrated in FIG. 5.
More specifically, as shown in FIG. 1, the signal generator 108 of the present invention includes a rotating shaft 101 operatively connected with the crankshaft (not shown) of a multi-cylinder internal combustion engine, and a rotating plate 102 fixedly mounted on the rotating shaft 101, as in the conventional signal generator 8 of FIG. 5. The rotating plate 102 has a plurality of first slits 103a formed therein at locations circumferentially spaced from each other at equal intervals, each of the slits 103a relating to a corresponding cylinder of the engine. The first slits 103a are disposed on a circle around the axis of the rotating shaft 101 and have substantially the same circumferential length. A second slit 103b is formed in the rotating plate 102 at a location near a specific one (e.g., corresponding to a specific reference cylinder #1) of the first slits 103a. The second slit 103b is disposed on the same circle on which the first slits 103a are disposed. In the illustrated example, the second slit 103b is circumferentially spaced a prescribed limited distance from the specific one of the first slits 103a in a direction opposite the rotating direction of the rotating shaft 101. In FIG. 1, the second slit 103b is illustrated to have a circumferential length less than that of the first slits 103a, but the circumferential length thereof may be equal to or greater than that of the first slits 103a. However, it is preferable that the circumferential length of the second slit 103b be much shorter than that of the first slits 103a so as to simplify the cylinder recognition process which will be described later with reference to the flow chart of FIG. 3. In addition, the second slit 103b may be disposed such that it is circumferentially spaced from the specific one of the first slits 103a in a direction in which the rotating shaft 101 rotates.
A photocoupler 104 is provided near the rotating plate 102 for generating an output signal when it senses that one of the first and second slits 103a, 103b in the rotating plate 102 passes a prescribed location during the rotation of the rotating plate 102. The photocoupler 104 includes a single pair of light emitting diode 105a and a light sensor 105b in the form of a photodiode which are disposed on the opposite sides of the rotating plate 102 in alignment with each other on the circle on which the first and second slits 103a, 103b are disposed. The light sensor 105b generates an output signal in the form of a square pulse when it receives the light, which was emitted from the light emitting diode 104 and which passed through the first slits 103a or the second slit 103b, i.e., at the time when one of the slits 103a, 103b is placed in alignment with the light emitting diode 104 and the light sensor 105.
Thus, as illustrated in FIG. 2, the output signal of the light sensor 105 includes a plurality of first or positional pulses L1' each in the form of a wide pulse relating to a corresponding first slit 103a and a second or cylinder recognition pulse L2' in the form of a narrow pulse corresponding to the second slit 103b. Each of the wide positional pulses L1' has a rising edge, which occurs at the leading edge of one of the first slits 103a (e.g., at the crank angle of 75 degrees before top dead center), and a falling edge, which occurs at the trailing edge thereof (e.g., at the crank angle of 5 degrees before top dead center). In the illustrated example, the narrow cylinder recognition pulse L2' follows a specific one of the wide positional pulses L1' corresponding to the specific reference cylinder, and has a rising edge, which occurs at the leading edge of the second slit 103b (e.g., slightly later than the falling edge of the specific one of the first wide pulses L1'), and a falling edge, which occurs at the trailing edge of the second slit 103b (e.g., at the crank angle of 5 degrees after top dead center).
The output signal of the signal generator 108 is amplified by an unillustrated amplifier and then fed to the base of an unillustrated output transistor which has the collector coupled to an interface circuit of a cylinder recognition means in the form of a microcomputer and the emitter grounded, as in the conventional cylinder recognition apparatus illustrated in FIG. 6.
The construction and operation of this embodiment other than the above are substantially similar to those of the conventional cylinder recognition apparatus as illustrated in FIGS. 4 through 7.
Next, the operation of this embodiment will be described in detail with particular reference to the flow chart of FIG. 3.
As the rotating plate 102 rotates in a direction indicated by arrow A in FIG. 1 in synchrony with the rotation of the engine, the light sensor 105b of the signal generator 108 generates an output signal including first pulses L1' and second pulses L2', as shown in FIG. 2. The microcomputer (not shown) receives via the unillustrated interface circuit the output signal of the signal generator 108, and processes it in the manner as shown in the flow chart of FIG. 7 in accordance with a control program stored therein.
Specifically, in Step S1, the length or pulse width t of each pulse L1' or L2' of the signal generator output signal as well as the period or pulse interval T between the rising edges of successive pulses are calculated so as to discriminate whether it is a positional pulse L1' or a cylinder recognition pulse L2'. In Step S2, the duty cycle t/T for each pulse is then calculated based on the pulse width t and the pulse interval T thus calculated. Subsequently, in Step S3, based on the duty cycle t/T thus calculated, the difference between the present or latest duty cycle data (t/T) n for the present or latest pulse L n and the preceding duty cycle data (t/T) n-1 for the preceding pulse L n-1 is calculated, and it is determined whether the absolute value of the difference {(t/T) n -(t/T) n-1 } is greater than a prescribed value α. If (t/T) n -(t/T) n-1 >α (i.e., the present or latest duty cycle (t/T) n for the present cylinder recognition pulse L 2 has greatly changed from the preceding duty cycle (t/T) n-1 for the specific positional pulse L 1 , e.g., the pulse width of a cylinder recognition pulse L 2 (i.e., the circumferential length of the second slit 103b) can be set to be much shorter than that of a positional pulse L1' (i.e., the circumferential length of the first slits 103a) ), then the program proceeds to Step S4 wherein the present pulse L n is determined to be a second pulse L2', and hence the specific reference cylinder #1 corresponding to the second pulse L2' is recognized or discriminated. Once the specific reference cylinder #1 is thus discriminated, it is automatically determined to which cylinders the succeeding pulses (L n+1 , L n+2 , . . . ) correspond since the operational order of the cylinders is predetermined. After the specific reference cylinder #1 has been recognized in this manner, a flag representative of the specific cylinder #1 is set in a register in the microcomputer, and the cylinder recognition process ends.
On the other hand, if it is determined in Step S3 that (t/T) n -(t/T) n-1 ≦α, the program immediately returns to the first Step S1, and the Steps S1 through S3 are then repeated until the specific cylinder #1 is recognized.
In this connection, in Step S3, instead of determining whether or not (t/T) n -(t/T) n-1 >α, the duty cycle t/T for each pulse L 1 , L 2 can be compared with a prescribed value β, and if t/T>β, the pulse is determined to be a specific positional pulse corresponding to the specific cylinder #1. This is because the duty cycle t/T for a specific positional pulse is generally much higher than that for the other positional pulse or for a cylinder recognition pulse. On the other hand, in cases where the duty cycle t/T for a cylinder recognition pulse is set to be much lower than that for the positional pulses, it is possible to determine a pulse to be a cylinder recognition pulse if the duty cycle t/T for the pulse is less than a prescribed value.
After a cylinder recognition pulse L2' corresponding to the specific cylinder #1 has once been recognized in the above manner, it becomes possible to discriminate the respective remaining cylinders based on the subsequent positional pulses L1', so various engine operations such as ignition, fuel injection, etc., can be properly controlled based on the rising edge and/or falling edge of each positional pulse L1'. For example, ignition can be controlled such that the current supply to the ignition coil of the engine is cut off at the falling edge of each positional pulse L1' so as to properly control the ignition timing of a corresponding cylinder. In this case, however, when a specific positional pulse L1' corresponding to the specific cylinder #1 has not yet been discriminated or recognized, ignition is controlled to take place at the falling edge of each pulse L1' or L2' of the signal generator output pulse. If a cylinder recognition signal L2' follows shortly after the falling edge of a specific positional pulse L1', as clearly shown in FIG. 2, a first ignition will take place in the specific cylinder #1 at the falling edge (e.g., at 5 degrees before TDC) of a specific positional pulse L1' corresponding to the specific cylinder #1, but a subsequent ignition will not take place at the falling edge (e.g., at 5 degrees after TDC) of a cylinder recognition pulse L2' following the specific positional pulse L1' since the first ignition already took place shortly before the falling edge of the cylinder recognition pulse L2' and there is no sufficient voltage built up on the ignition coil during a short time between the falling edges (e.g., between 5 degrees before TDC and 5 degrees after TDC) of the successive pulses L1', L2'. To this end, it is necessary to set the cylinder recognition pulse L2' and hence the position of the second slit 103b in the rotating plate 102 in such a manner that the falling edge of the cylinder recognition pulse L2' is located sufficiently near to the falling edge of the preceding specific positional pulse L1' so as to prevent the build-up of a high voltage on the ignition coil during the period therebetween but remote from the rising edge of the following positional signal L1' so as to allow a high voltage to be developed during the time therebetween. As a result, there will be no problem of improper ignition or misfiring.
Here, it is to be noted that for the purpose of controlling engine operations such as fuel injection other than the above-mentioned ignition, a cylinder recognition pulse L2' may take place before a specific positional pulse L1' corresponding to the specific cylinder #1, i.e., between a specific positional pulse and the preceding positional pulse. In this case, too, the process for discriminating or recognizing a specific positional signal and hence the specific cylinder #1 is substantially the same as the aforesaid one as illustrated in the flow chart of FIG. 7.
Although in the above embodiment, in Step S2 in FIG. 3, the duty cycle t/T for each pulse L 1 or L 2 of the output signal of the signal generator 108 is utilized for discriminating a specific positional signal corresponding to the specific cylinder #1, the ratio t/(T-t) of the high-level to low-level period for each pulse L1', L2' may instead be employed. In this case, a change in the high-level to low-level period ratio t/(T-t) between a positional signal L1' and a cylinder recognition signal L2' becomes greater than a change in the duty cycle t/T therebetween, so sensitivity in the discrimination or recognition of the specific cylinder #1 is accordingly improved. | A cylinder recognition apparatus for a multi-cylinder internal combustion engine capable of recognizing a specific reference cylinder as well as the remaining cylinders of the engine by use of only a single signal. A signal generator generates a single output signal in synchrony with the rotation of the engine, the output signal including a plurality of positional pulses each representative of prescribed rotational positions of a corresponding cylinder, and a cylinder recognition pulse at a location near a specific one of the positional pulses corresponding to a specific cylinder. A microcomputer discriminates the cylinder recognition pulse among the signal generator output pulses so as to recognize the specific positional pulse corresponding to the speicfic cylinder. The microcomputer calculates the pulse width of each pulse in the signal generator output signal and the pulse interval between the rising or falling edges of successive pulses, calculates the ratio of the pulse width to the pulse interval for each pulse, and discriminates the cylinder recognition pulse based on the ratio thus obtained. | 5 |
PRIORITY CLAIM TO RELATED US APPLICATIONS
To the full extent permitted by law, the present U.S. Non-provisional patent application, is a Continuation-in-Part of, and hereby claims priority to and the full benefit of U.S. Non-provisional application entitled “Control Motion Hinge,” having assigned Ser. No. 12/775,302, filed on May 6, 2010, incorporated herein by reference in its entirety.
FIELD OF THE INVENTION
The present invention relates generally to hinge and more specifically to a door hinge with a motion closure system for soft closure of the door.
BACKGROUND OF THE INVENTION
The conventional door hinge or butt-hinge is composed of two leaves each engages with the other by means of a pivot pin and interlocking sleeve, knuckle or pintle. One leaf is fixed on the door edge and the other is fixed on the door frame. One or more hinges are used to pivot the door when opening or closing the door. For automatically closure of the door with a conventional hinge, a hydraulic system, spring system or a combination system is typically affixed to the upper portion of door and to the horizontal beam of the upper door frame, thereby adding an industrial appearance to the door assembly. In addition, such door closing systems generally exerts a continuous resisting force requiring a big force to be applied to push the door open or hold the door in an open position, preventing the door from free swinging.
Moreover, such door closing systems apply a non-uniform force to the upper portion of the door disadvantageously resulting in a force offset from the rotational axis of the hinge assembly, thus deforming the door, hinge, latch/lock and frame over time. Furthermore, these door closing systems frequently utilize a separate mechanical mechanism to lock the door in a full open position such as a door stop or a mechanical elbow linkage requiring a separate installation. When a door is closed with the assistance of such door closing systems, it is typically forced to move in its closing direction rapidly, causing a noise to the ear and forceful impact, wherein the main elements the hinge, lock and door elements are impaired over time due to such force.
Therefore, it is readily apparent that there is a recognizable unmet need for control motion hinge for soft and quiet closure of a door during final approach, wherein such control motion hinge is integrated into the hinge or hidden within the door jam, frame or door, and wherein such control motion hinge is non-continuous, thereby allowing the door to swing freely through the door hinges full range of motion to an automatic full open hold position, and reduce the stress on the door, hinge, latch/lock and frame.
BRIEF SUMMARY OF THE INVENTION
Briefly described, in a preferred embodiment, the present apparatus overcomes the above-mentioned disadvantage, and meets the recognized need for such an apparatus by providing a control motion hinge comprising, in general, a first leaf hinge to secure a first pin, a second hinge to secure a first pin, a link positioned between the first and second leaf hinge, a flat spring wrapped around the knuckle of the first and second leaf hinge, activates a closure cycle of the control motion hinge pulling the door closed.
According to its major aspects and broadly stated, the present apparatus in its preferred form is a control motion hinge, comprising a first leaf hinge with three knuckles to secure a first pin, wherein the two outer knuckles have roller knuckles, a link having a two knuckles on a first end to interlock with the first leaf hinge and a single knuckle on a second end, a second leaf hinge with two knuckles to secure a second pin when interlocked with the second end of the link, wherein the two knuckles of the second leaf hinge have a roller path for engaging the roller of the first leaf hinge, wherein such rollers traverse the roller path, a first spring device positioned between said first leaf hinge and said link to apply a force therebetween, and thus softly closing the door reducing the sound of closure during the final approach of the door.
More specifically, the preferred embodiment of the present apparatus further comprising a roller path having a roller stop at a first end of the roller path and a roller ramp or plateau at a second end of the roller path for holding the closing system in an open door position, wherein release thereof activates a seamless closure cycle of the control motion hinge pulling the door closed.
In a further preferred embodiment of the control motion hinge, including a first hinge pin, a first leaf hinge having two or more knuckles to removably secure the first hinge pin and adapted to be fixed to the jam, a second hinge pin, a second leaf hinge having two or more knuckles to removably secure the second hinge pin and adapted to be fixed to the door, and a link having one or more knuckles on a first end to interlock with the two or more knuckles of the first leaf hinge and one or more knuckles on a second end to interlock with the two or more knuckles of the second leaf hinge.
In a further exemplary embodiment the control motion hinge with a torsion spring, including a first hinge pin, a first leaf hinge having two or more knuckles to removably secure the first hinge pin and adapted to be fixed to the jam, a second hinge pin, a second leaf hinge having two or more knuckles to removably secure the second hinge pin and adapted to be fixed to the door, a link having one or more knuckles on a first end to interlock with the two or more knuckles of the first leaf hinge and one or more knuckles on a second end to interlock with the two or more knuckles of said second leaf hinge, and a first spring device positioned between said first leaf hinge and said link.
In a further exemplary embodiment a method for an automatic closing hinge, including the steps of: providing a first hinge pin, a first leaf hinge having two or more knuckles to removably secure the first hinge pin and adapted to be fixed to the jam, wherein at least one of the two or more knuckles of the first leaf hinge further comprises a pair of roller sleeves, a roller pin and a roller, a second hinge pin, a second leaf hinge having two or more knuckles to removably secure the second hinge pin and adapted to be fixed to the door, wherein at least one of the two or more knuckles of the second leaf hinge further comprises a roller path for engaging the roller of the first leaf hinge, a link having one or more knuckles on a first end to interlock with the two or more knuckles of the first leaf hinge and one or more knuckles on a second end to interlock with the two or more knuckles of the second leaf hinge, and a spring in contact with an upper surface of the link and an outer surface of the two or more knuckles of the second leaf hinge, rotating the first leaf hinge apart from the second leaf hinge, traversing the roller along the roller path, expanding the spring while the first leaf hinge rotates apart from the second leaf hinge, and contracting the spring returns the first leaf hinge toward the second leaf hinge and the roller returns along the roller path.
Accordingly, a feature of the present control motion hinge is its ability to provide a hinge with a continuous closure force, thus allowing the door to close at a controlled rate of speed when the hinge is released.
Another feature of the present control motion hinge is its ability to provide a hinge wherein the closure system integrated as part of the hinge or knuckle, or hidden within the door jam, door frame or within the door, rendering an enhanced aesthetic appearance.
Still another feature of the present control motion hinge is its ability to provide a dampening closure cylinder utilizing hydraulic oil, nitric oxide, air or other compressible material.
Yet another feature of the present control motion hinge is its ability to provide a hinge that softly closes the door reducing the sound of closure during the final approach of the door.
Yet another feature of the present control motion hinge is its ability to provide a door hinge with a soft closure system that prevents a door from rapid closing so as to protect the door, jam, doorframe, or surroundings from being damaged.
Yet another feature of the present control motion hinge is its ability to provide a hinge with a soft closure system that cushions door closure, thereby reducing the stress on the door, hinge, latch/lock, jam, and frame.
Yet another feature of the present control motion hinge is its ability to provide a hinge with seamless motion throughout the hinges full range of motion.
Yet another feature of the present control motion hinge is its ability to provide a simple, compact, and inexpensive hinge with a seamless lock open and release mechanism and a closure system.
Yet another feature of the present control motion hinge is its ability to provide a door closer, which can smoothly and effectively close the door after opening and releasing.
Yet another feature of the present control motion hinge is its ability to hold the door in a full open position, release the door there from, and maintain a controlled closure motion through the door's final approach.
Yet another feature of the present control motion hinge is its ability to reduce the opening force required to open the door facilitating accessibility for small children, elderly, handicapped and those with disabilities.
Yet another feature of the present control motion hinge is its ability to provide a door hinge that can motion the door to a closed position in a smooth and slow manner during final approach.
Yet another feature of the present control motion hinge is its ability to provide a hinge assembly that can be sold as a replacement hinge assembly for retrofitting and improving existing hinges.
Yet another feature of the present control motion hinge is its ability to provide a hinge assembly that meets industry life cycle requirements.
Yet another feature of the present control motion hinge is its ability to provide a hinge assembly that
These and other features of the control motion hinge will become more apparent to one skilled in the art from the following Detailed Description of the Preferred and Selected Alternate Embodiments and Claims when read in light of the accompanying drawing Figures.
BRIEF DESCRIPTION OF THE DRAWINGS
The present control motion hinge will be better understood by reading the Detailed Description of the Preferred and Selected Alternate Embodiments with reference to the accompanying drawing figures, in which like reference numerals denote similar structure and refer to like elements throughout, and in which:
FIG. 1 is a front view of a prior art door assembly showing three hinges spaced vertically between a door frame and a swinging door, showing the hinges in a closed state;
FIG. 1.1 is an enlarged perspective view showing a prior art door hinge shown in FIG. 1 in the open state;
FIG. 2 is a perspective view of a control motion hinge according to a preferred embodiment;
FIG. 3 is an enlarged perspective view of the control motion hinge of FIG. 2 , shown in the open state;
FIGS. 4 , 4 . 1 , 4 . 2 , 4 . 3 , and 4 . 4 are exploded perspective views of the two leaf hinges, link and flat spring assembly according to a preferred embodiment;
FIG. 4 . 1 . 1 is a perspective view of the leaf hinge and torsion spring assembly according to an exemplary embodiment;
FIG. 4 . 2 . 1 is a perspective view of link and torsion spring assembly according to an exemplary embodiment;
FIGS. 5 , 5 . 1 , 5 . 2 , 5 . 3 , 5 . 4 and 5 . 5 are expanded partial cross-sectional side views of the control motion hinge of FIG. 2 , shown in the closed, partially open, and open states;
FIG. 5 . 4 . 1 expanded partial cross-sectional side views of the control motion hinge of FIGS. 4 . 1 . 1 and 4 . 2 . 1 , shown in the and open state;
FIGS. 6 , 6 . 1 and 6 . 2 are expanded partial cross-sectional side views of the control motion hinge with integrated dampener of FIG. 2 , shown in the closed and open states; and
FIGS. 7 , 7 . 1 , 7 . 2 , 7 . 3 , 7 . 5 and 7 . 6 are expanded partial cross-sectional side views of the control motion hinge of FIGS. 4 . 1 . 1 and 4 . 2 . 1 , shown in the closed, partially open, and open states.
DETAILED DESCRIPTION OF THE INVENTION
In describing the preferred and alternate embodiments of the present invention, as illustrated in FIGS. 1-7 specific terminology is employed for the sake of clarity. The present invention, however, is not intended to be limited to the specific terminology so selected, and it is to be understood that each specific element includes all technical equivalents that operate in a similar manner to accomplish similar functions.
Referring now to FIGS. 1 and 1 . 1 , there is depicted a prior art door D, door jam J, door header I and three hinge assembly H 1 , H 2 , and H 3 . The door D, which swings inward, toward the viewer as depicted in FIG. 1 , fits closely to jam J at both its hinge edge A 1 and its opposite or latch edge A 2 . Door A may be configured to swing inward or outward by switching the configuration of hinge assembly H 1 , H 2 , and H 3 . It should be noted, also, that no hinge is exposed to view along the hinge edge A 1 when the door is closed as viewed from the other side of door D.
Referring now to FIG. 1.1 , a perspective view of a typical prior art hinge assembly H having two hinge leaves formed as a pair, stationary hinge leaf L 1 and rotatable hinge leaf L 2 , and connected therebetween by hinge pin P. The hinge leaves (L 1 , L 2 ) have offset knuckles K which when interlinked are preferably joined together by the hinge pin P. Each hinge leaf is shown with three mount holes M 1 , M 2 , and M 3 formed in the hinge leaves. The stationary hinge leaf L 1 is secured to door jam J utilizes a flathead screw, nail or the like driven through mount holes M of such stationary hinge leaf L 1 , while the rotatable hinge leaf L 2 is secured to opening-and-closing door D, or the like, also utilizes a flat screw, nail or the like driven through mount holes M of such rotatable hinge leaf L 2 . To hang door D to door jam J, door D is positioned near door jam J so that knuckles K of stationary hinge leaf L 1 are interlinked with knuckles K of rotatable hinge leaf L 2 and pin P is inserted into such interlinked knuckles of stationary hinge leaf L 1 and rotatable hinge leaf L 2 , thereby enables door A to freely rotationally swing about pin P with stationary hinge leaf L 1 affixed to door jam J.
Referring now to FIGS. 2 and 3 , by way of example, and not limitation, there is illustrated a perspective view of control motion hinge 10 in accordance with a preferred embodiment of the present invention. Preferably, control motion hinge 10 , having a first hinge member such as stationary hinge leaf 12 , a second hinge member such as rotatable hinge leaf 14 , knuckles 18 , 19 , counter leaver member such as link 21 , and a first hinge pin such as stationary hinge pin 16 and a second hinge pin such as rotatable hinge pin 17 are preferably formed of a suitable material, such as aluminum, brass, iron, steel, or other metals, plastic, including various finishes from chrome, antiqued copper, black, and brass (either plated or pure brass) or the like, capable of providing structure and strength to hinge assembly H. Preferably, the material includes other suitable characteristics, such as durability, water-resistance, light weight, malleable, oxidation resistance, ease of workability, or other beneficial characteristic understood by one skilled in the art. Moreover, hinge 10 may come in an endless variety of types, shapes, sizes and purposes, including but not limited to butt hinges, strap hinge, spring hinge, wide throw hinge, left hand, right hand hinge and the like.
Referring now to FIGS. 2 and 3 , the present invention in its preferred embodiment is a control motion hinge 10 . Preferably, control motion hinge 10 comprises two hinge leaves formed as a pair, stationary hinge leaf 12 , and rotatable hinge leaf 14 , and connected therebetween by a link 21 and stationary hinge pin 16 and rotatable hinge pin 17 . The hinge leaves ( 12 , 14 ) preferably have offset knuckles 18 , which interlocked with offset knuckles 19 of link 21 and thereby joined together as a combination linkage by stationary hinge pin 16 and rotatable hinge pin 17 .
Referring now to FIGS. 2 and 3 , control motion hinge 10 is preferably shown in a partial open position and shown having a spring device such as flat spring 22 coupled around offset knuckles 18 of stationary hinge leaf 12 and offset knuckles 19 of link 21 .
Referring now to FIG. 3 , control motion hinge 10 is preferably shown in an approximately full open position and shown having roller 32 positioned between roller sleeve 33 and roller sleeve 35 , which preferably are positioned on the underside surface of one or more offset knuckles 18 of rotatable hinge leaf 14 and held rotationally in position by roller pin 36 . In operation, roller 32 traverses roller path 34 of offset knuckles 18 of stationary hinge leaf 12 between roller stop 38 and roller closing ramp 31 . Moreover, one or more mount holes 37 (four shown) are positioned in stationary hinge leaf 12 and rotatable hinge leaf 14 .
Referring now to FIGS. 4 , 4 . 1 , 4 . 2 , 4 . 3 , 4 . 4 , by way of example, and not limitation, there is illustrated an exploded perspective view of control motion hinge 10 in accordance with a preferred embodiment of the present invention. Referring again to FIG. 4.1 , there is illustrated an exploded perspective view of rotatable hinge leaf 14 of control motion hinge 10 . Preferably, rotatable hinge leaf 14 includes flat single geometric plane 41 arranged as rectangle or other geometric shape and further preferably having one or more mount holes 37 (four shown) positioned in rotatable hinge leaf 14 for removably attach rotatable hinge leaf 14 to door D (as shown in FIGS. 2 and 3 ) utilizes a flathead screw, nail or the like driven through mount holes 37 of such rotatable hinge leaf 14 . Edge 43 preferably runs the perimeter of plane 41 . On one segment of edge 43 of rotatable hinge leaf 14 preferably includes one or more offset knuckles 18 . 1 , 18 . 2 , and 18 . 3 having pin hole 45 . 1 operative to run linearly there through each offset knuckle 18 . 1 , 18 . 2 , and 18 . 3 . Referring again to FIG. 4.2 , there is illustrated an exploded perspective view of link 21 of control motion hinge 10 . Preferably, link 21 includes on one end of link one or more offset knuckles 19 . 1 and 19 . 2 having pin hole 45 . 2 operative to run linearly there through each offset knuckle 19 . 1 and 19 . 2 .
In use, offset knuckles 19 . 1 and 19 . 2 of link 21 are preferably interlock or fit together closely with offset knuckles 18 . 1 , 18 . 2 , and 18 . 3 of rotatable hinge leaf 14 , whereby rotatable hinge pin 17 is positioned within pin holes 45 . 1 of offset knuckles 18 . 1 , 18 . 2 , and 18 . 3 and pin holes 45 . 2 of offset knuckles 19 . 1 and 19 . 2 to rotationally connect link 21 and rotatable hinge leaf 14 .
Referring again to FIG. 4.1 , there is illustrated an exploded perspective view of rotatable hinge leaf 14 of control motion hinge 10 . Preferably, roller sleeve 33 and roller sleeve 35 are affixed to the adjacent or situated near or close or touching exterior surface of both knuckles 18 . 1 and 18 . 3 and roller 32 is positioned there between roller sleeve 33 and roller sleeve 35 and held in position when roller pin 36 is positioned within pin holes 45 . 3 of roller sleeve 33 and roller sleeve 35 .
Referring to FIG. 4 . 1 . 1 , there is illustrated an exploded perspective view of rotatable hinge leaf 14 of control motion hinge 10 . Preferably, in place thereof of knuckle 18 . 2 (or one or more knuckles 18 . 1 - 18 . 3 ) rotatable hinge leaf 14 includes a trimmed or cutout or formed section such as area 18 . 2 . 1 , wherein a second spring device such as second torsion spring 92 may be positioned. Preferably second torsion spring 92 is configured to coil around rotatable hinge pin 17 within area 18 . 2 . 1 when rotatable hinge pin 17 is positioned within pin hole 45 . 2 of knuckles 19 . 1 and 19 . 2 of link 21 and pin holes 45 . 1 of offset knuckles 18 . 1 and 18 . 3 of rotatable hinge leaf 14 .
In use, one end such as first end 91 of second torsion spring 92 is slidably affixed or anchored in an aperture such as hole 94 of rotatable hinge leaf 14 and the other end such as second end 93 of second torsion spring 92 is configured to engage a wheel such as roller 35 . 1 mounted on roller mount 38 . 1 , shown in FIG. 5 . 4 . 1 , (or second end 93 may engage any other independent position of stationary hinge leaf 12 ). Roller mount 38 . 1 is preferably positioned on plane 41 of stationary hinge leaf 12 and preferably positioned approximate area 18 . 2 . 1 (or positioned approximate one or more knuckles 18 . 1 - 18 . 3 ) of stationary hinge leaf 12 . Preferably, second torsion spring 92 functions as a torsional force such as non-continuous secondary force f between rotatable hinge leaf 14 and roller 35 . 1 when door D is pushed to near-full-open position (approximately 110 degrees; however, this may be between approximately 90 degrees and 130 degrees). In general second torsion spring 92 operates as an aid or assist to first torsion spring 82 (shown in FIG. 4 . 2 . 1 ), preferably when rotatable hinge leaf 14 (or door D) is in a neutral zone/near-full-open position (approximately 90 degrees and 130 degrees) where torsional force such as force f of first torsion spring 82 is unable to close door D and requires assistance from second torsion spring 92 to enable soft closure of door D. In the alternative, in order to close door D, torsional force such as force f of first torsion spring 82 must be oversized resulting in too much energy from first torsion spring 82 at door D closure, which are greater than fire code and Americans with Disability Act force limits of a maximum of five (5) pounds; thus causing a hard closure rather than a soft closure of door D.
It is contemplated herein that second torsion spring 92 assistance through door D's neutral zone enables reduced sizing of first torsion spring 82 to meet fire code and Americans with Disability Act force limits of a maximum of five (5) pounds. Moreover, the combination torsion spring 82 / 92 preferably enables reduced sizing of first torsion spring 82 to approximately one (1) pound or less to effective soft closure of door D.
Referring again to FIG. 4.3 , there is illustrated an exploded perspective view of stationary hinge leaf 12 of control motion hinge 10 . Preferably, stationary hinge leaf 12 includes flat single geometric plane 41 arranged as rectangle or other geometric shape and further preferably having one or more mount holes 37 (four shown) positioned in stationary hinge leaf 12 for removably attach stationary hinge leaf 12 to jam J (as shown in FIGS. 2 and 3 ) utilizes a flathead screw, nail or the like driven through mount holes 37 of such stationary hinge leaf 12 . Edge 43 preferably runs the perimeter of plane 41 . On one segment of edge 43 preferably includes one or more offset knuckles 18 . 4 and 18 . 5 having pin hole 45 . 4 operative to run linearly there through each offset knuckle 18 . 4 and 18 . 5 . Referring again to FIG. 4.2 , there is illustrated an exploded perspective view of link 21 of control motion hinge 10 . Preferably, link 21 preferably includes on the other end at least one offset knuckle 19 . 3 having pin hole 45 . 5 operative to run linearly there through knuckle 19 . 3 .
In use, offset knuckle 19 . 3 of link 21 is preferably interlocked with offset knuckles 18 . 4 and 18 . 5 of stationary hinge leaf 12 , whereby stationary hinge pin 16 is positioned within pin hole 45 . 5 of offset knuckle 19 . 3 and pin holes 45 . 4 of offset knuckles 18 . 4 and 18 . 5 to rotationally connect link 21 and stationary hinge leaf 12 .
Furthermore, when in combination use, stationary hinge pin 16 is positioned within pin hole 45 . 5 of offset knuckle 19 . 3 and pin holes 45 . 4 of offset knuckles 18 . 4 and 18 . 5 to rotationally connect link 21 and stationary hinge leaf 12 , and rotatable hinge pin 17 is positioned within pin holes 45 . 1 of offset knuckles 18 . 1 , 18 . 2 , and 18 . 3 and pin holes 45 . 2 of offset knuckles 19 . 1 and 19 . 2 to rotationally connect link 21 and rotatable hinge leaf 14 , control motion hinge 10 preferably is a three member linkage hinge constructed of stationary hinge leaf 12 , link 21 , and rotatable hinge leaf 14 .
Alternatively, referring to FIG. 4 . 2 . 1 , there is illustrated an exploded perspective view of link 21 of control motion hinge 10 . Preferably, link 21 preferably includes on the other end one or more offset knuckles 19 . 3 A and 19 . 3 B having pin hole 45 . 5 operative to run linearly there through knuckle offset knuckles 19 . 3 A and 19 . 3 B.
Furthermore, when in combination use, stationary hinge pin 16 is positioned within pin hole 45 . 5 of offset knuckle offset knuckles 19 . 3 A and 19 . 3 B and pin holes 45 . 4 of offset knuckles 18 . 4 and 18 . 5 to rotationally connect link 21 and stationary hinge leaf 12 , and rotatable hinge pin 17 is positioned within pin holes 45 . 1 of offset knuckles 18 . 1 , 18 . 2 , and 18 . 3 and pin holes 45 . 2 of offset knuckles 19 . 1 and 19 . 2 to rotationally connect link 21 and rotatable hinge leaf 14 , control motion hinge 10 preferably is a three member linkage hinge constructed of stationary hinge leaf 12 , link 21 , and rotatable hinge leaf 14 (as shown in FIG. 4 ).
Moreover, an open area such as notch 19 . 4 is preferably formed between one or more offset knuckles 19 . 3 A and 19 . 3 B of link 21 , wherein a spring device such as first torsion spring 82 may be positioned. Preferably first torsion spring 82 is configured to coil around stationary hinge pin 16 within notch 19 . 4 when stationary hinge pin 16 is positioned within pin hole 45 . 5 of knuckles 19 . 3 A and 19 . 3 B of link 21 and pin holes 45 . 4 of offset knuckles 18 . 4 and 18 . 5 of stationary hinge 12 .
In use, one end such as first end 81 of first torsion spring 82 is slidably affixed or anchored in an aperture such as hole 84 in link 21 and the other end such as second end 83 of first torsion spring 82 is slidably anchored or affixed in an aperture such as notch 85 in stationary hinge leaf 12 (as shown in FIG. 5 . 2 . 1 ). Preferably, first torsion spring 82 functions as a torsional force such as continuous primary force f (as shown in FIG. 5 . 4 . 1 ) when link 21 rotates counter-clockwise about stationary hinge pin 16 . Force f returns link 21 to its starting position where rotatable hinge leaf 14 is in contact with stationary hinge 12 . In general first torsion spring 82 operates, preferably when an arc rotation (kinetic) of link 21 about stationary hinge pin 16 positioned within pin holes 45 . 4 of offset knuckles 18 . 4 and 18 . 5 rotationally separates link 21 from stationary hinge leaf 12 , which further results in an opposite primary force f (potential) of first torsion spring 82 to return link 21 and stationary hinge leaf 12 to their original positions.
It is contemplated herein that first torsion spring 82 applies a continuous primary force f on link 21 to return link 21 and stationary hinge leaf 12 to their original positions. Fire code and Americans with Disability Act limit door D force to a maximum of five (5) pounds of force.
Moreover, torsion spring 82 / 92 are preferably formed of a suitable material, such as metal, steel, stainless steel or the like, capable of providing suitable characteristics, such as torque, twisting force, rotational resistance/force, shape memory, magnetism, durability, water-resistance, light weight, heat-resistance, chemical inertness, oxidation resistance, ease of workability, or other beneficial characteristic understood by one skilled in the art.
It is contemplated herein that the size and dimensions of roller path 34 is preferably utilized to set the neutral point between stationary hinge leaf 12 and rotatable hinge leaf 14 . For example, without roller path 34 (i.e. plane 41 of stationary hinge leaf 12 ) the approximate neutral point is approximately 66 degrees between stationary hinge leaf and rotatable hinge leaf 14 . By introducing a upward, linear or f(x) slope to roller path 34 this in turn raises the approximate neutral point to preferably approximately 85 degrees between stationary hinge leaf 12 and rotatable hinge leaf 14 ; however, this may be between approximately 80 degrees and approximately 110 degrees and thereafter raise with diminishing return. It is recognized herein that roller path 34 is not critical for the counter leaver action of control motion hinge 10 , but rather stationary hinge leaf 12 , stationary hinge pin 16 , link 21 , rotatable hinge pin 17 , and rotatable hinge leaf 14 create control motion hinge 10 counter leaver action.
It is recognized that plane 41 of rotatable hinge leaf 14 and stationary hinge leaf 12 is preferably configured as a four (4) inch pattern rated for approximately 75 pounds or a four and a half (4.5) inch pattern rated for approximately 75-115 pounds; however, different sizes and/or configurations are contemplated herein.
Referring again to FIG. 4.4 , there is illustrated an exploded perspective view of flat spring 22 of control motion hinge 10 . Preferably, flat spring 22 is formed to match the exterior surface and contours of offset knuckles 18 . 4 and 18 . 5 of stationary hinge leaf 12 and is generally ‘C’ shaped. Moreover, flat spring 22 is preferably formed of a suitable material, such as metal, steel, stainless steel or the like, capable of providing suitable characteristics, such as tension, extension, expansion, shape memory, magnetism, durability, water-resistance, light weight, heat-resistance, chemical inertness, oxidation resistance, ease of workability, or other beneficial characteristic understood by one skilled in the art. Preferably, flat spring 22 includes inner-upper surface 49 and inner-lower surface 51 and when in use both surfaces are in contact with the outer surface of offset knuckles 18 . 4 and 18 . 5 of stationary hinge leaf 12 . Moreover, inner-upper surface 49 of flat spring 22 is preferably arranged to rest on upper surface 44 of link 21 and attached thereto by spring screws or the like inserted in screw holes 53 formed in flat spring 22 and screw holes formed in upper surface 44 of link 21 . In use, flat spring 22 is preferably positioned on the outer surface of offset knuckles 18 . 4 and 18 . 5 of stationary hinge leaf 12 and on upper surface 44 of link 21 , in order to function as a spring when link 21 rotates about stationary hinge pin 16 positioned within pin hole 45 . 5 of offset knuckle 19 . 3 of link 21 and pin holes 45 . 4 of offset knuckles 18 . 4 and 18 . 5 . In general flat spring 22 operates, preferably when an arc rotation (kinetic) of link 21 about stationary hinge pin 16 positioned within pin holes 45 . 4 of offset knuckles 18 . 4 and 18 . 5 separates inner-upper surface 49 of flat spring 22 from inner-lower surface 51 of flat spring 22 , which further results in an opposite force (potential) of flat spring 22 to return inner-upper surface 49 and inner-lower surface 51 of flat spring 22 to their original positions.
It is contemplated that roller pin 36 , rotatable hinge pin 17 , stationary hinge pin 16 , and screws 47 could be interchangeably replaced with pins, screws bolts, pins and cotter keys, rivets or other like attachment devices.
Hinge Open Cycle
Referring now to FIGS. 5 , 5 . 1 , 5 . 2 , 5 . 3 , 5 . 4 , 5 . 5 by way of example, and not limitation, there is illustrated a series of side views of control motion hinge 10 in motion, in accordance with a preferred embodiment of the present invention. Referring again to FIG. 5.1 , there is illustrated a side view of control motion hinge 10 shown in a hinge-closed position with door D closed against jam J. Preferably, roller 32 and roller sleeve 35 of rotatable hinge leaf 14 are positioned against roller stop 38 of roller path 34 of offset knuckles 18 . 5 of stationary hinge leaf 12 . Preferably, arch a in FIG. 5.1 is the angle between plane 41 of stationary hinge leaf 12 and upper surface 44 of link 21 . Preferably, arc a in FIG. 5.1 comprise equivalent arc angle of −5 degrees; however, arc a may be between approximately 0 degrees and −10 degrees. Preferably, arc a 1 in FIG. 5.1 is the angle between plane 41 of stationary hinge leaf 12 and rotatable hinge leaf 14 . Preferably, arc a 1 in FIG. 5.1 comprise equivalent arc angle of 0 degrees; however, arc a 1 may be between approximately 2 degrees and −2 degrees.
Referring again to FIG. 5.2 , there is illustrated a side view of control motion hinge 10 shown in a hinge-beginning-to-open position. Preferably, as door D is pushed open expands arc a 1 , rotatable hinge leaf 14 rotates about rotatable hinge pin 17 of offset knuckle 18 . 3 (similarly with 18 . 1 , 18 . 2 not shown) of rotatable hinge leaf 14 , which further rotates link 21 about stationary hinge pin 16 of offset knuckle 18 . 5 (similarly with 18 . 4 not shown) of stationary hinge leaf 12 . Rotatable hinge leaf 14 is preferably configured having the center-point of rotatable hinge pin 17 of offset knuckle 18 . 5 and the center-point of roller pin 36 of roller 32 and roller sleeve 35 are preferably length L 1 apart. Preferably, center-points comprise equivalent length L 1 of ⅜ inch; however, length L 1 may be between approximately ¼ inch and approximately ½ inches. Moreover, when in use, the greater length L 1 between center-points of rotatable hinge pin 17 and roller pin 36 of roller 32 and roller sleeve 35 results in an increased arc a of rotation of link 21 about stationary hinge pin 16 of offset knuckles 18 . 4 , which further results in an increased opposite force f of flat spring 22 to return inner-upper surface 49 and inner-lower surface 51 of flat spring 22 to their original positions. Preferably, as arc a moves slightly, a 1 moves at much greater arc angle; thus, allows flat spring 22 to maintain optimum force f between inner-upper surface 49 and inner-lower surface 51 of flat spring 22 . The ratio of arc a to arc a 1 and equivalent force f are proportional to length L 1 .
Referring again to FIG. 5.3 , there is illustrated a side view of control motion hinge 10 shown in a hinge-mostly-open position. Preferably, as door D is pushed further open expands arc a 1 , rotatable hinge leaf 14 rotates further about rotatable hinge pin 17 of offset knuckle 18 . 3 (similarly with 18 . 1 , 18 . 2 not shown) of rotatable hinge leaf 14 , which slightly rotates link 21 about stationary hinge pin 16 of offset knuckle 18 . 5 (similarly with 18 . 4 not shown) of stationary hinge leaf 12 . It is contemplated herein that as arc a moves slightly, a 1 moves at much greater arc angle; thus, allows flat spring 22 to maintain optimum force f between inner-upper surface 49 and inner-lower surface 51 of flat spring 22 . First, when roller 32 reaches neutral point 52 of roller path 34 then arc a of rotation of link 21 about stationary hinge pin 16 of offset knuckles 18 . 5 has reached its maximum rotation (arc a is 38 degrees; however, arc a may be between approximately 15 degrees and 50 degrees) and inner-upper surface 49 and inner-lower surface 51 of flat spring 22 have reached the maximum distance of separation, which results in the maximum opposite force f of flat spring 22 to return inner-upper surface 49 and inner-lower surface 51 of flat spring 22 to their original positions. Second, when roller 32 reaches neutral point 52 of roller path 34 then arch a 1 in FIG. 5.2 the angle between plane 41 of stationary hinge leaf 12 and upper surface 44 of link 21 is comprise equivalent arc angle of 82 degrees; however, arc a 1 may be between approximately 60 degrees and 95 degrees. It should be recognized that force f can change arc a 1 in either direction to maximum angle of 110 degrees; however, arc a 1 may be between approximately 100 degrees and 180 degrees, or return arc a 1 to a closed position of 0 to −5 degrees. Third, when roller 32 reaches neutral point 52 of roller path 34 then upper surface 44 of link 21 lifts above upper exterior surface of offset knuckles 18 . 5 (similarly with 18 . 4 not shown) of stationary hinge leaf 12 loads flat spring 22 . Moreover, when roller 32 reaches neutral point 52 of roller path 34 then roller 32 preferably climbs to the top of roller path 34 an altitude preferably of length L 3 (shown in FIG. 5.4 ), wherein door D reaches approximately eighty-two (82) degrees arc a 1 hold-open position of door D (other degrees are contemplated herein). Preferably, length L 3 comprise equivalent of 3/16 inch as shown; however, length L 3 may be between approximately 0 inch and approximately ⅜ inch.
Referring again to FIG. 5.4 , there is illustrated a side view of control motion hinge 10 shown in a hinge near full-open position. Preferably, as door D is pushed to full open arc a 1 (approximately 110 degrees; however, arc a 1 may be between approximately 100 degrees and 130 degrees,) and rotatable hinge leaf 14 rotates still further about rotatable hinge pin 17 of offset knuckle 18 . 3 (similarly with 18 . 1 , 18 . 2 not shown) of rotatable hinge leaf 14 about offset knuckle 19 . 1 and 19 . 2 of link 21 , which partially reverse rotates (opposite direction) link about stationary hinge pin 16 of offset knuckle 18 . 5 (similarly with 18 . 4 not shown) of stationary hinge leaf 12 about offset knuckle 19 . 3 of link 21 , and reduces arc a and force f; but, moves arc a 1 to maximum open angle of 110 degrees, however, arc a 1 may be between approximately 100 degrees and 130 degrees; thus allows roller 32 to traverse horizontally along hold-open ramp 54 of roller path 34 in a linear direction away from the center-point of stationary hinge pin 16 . Moreover, FIG. 5.4 illustrates additional measurements. The first is preferably the center-points between stationary hinge pin 16 and rotatable hinge pin 17 , length L 4 . Preferably, length L 4 comprise equivalent of ⅝ inch as shown; however, length L 3 may be between approximately ⅜ inch and approximately ¾ inch. The second is preferably the travel distance of roller 32 from closed door to neutral point 52 of roller path 34 , length L 2 . Preferably, length L 2 comprise equivalent of ⅝ inch as shown; however, length L 2 may be between approximately ½ inch and approximately ¾ inch.
It is contemplated herein that flat spring 22 is preferably configured to enable rotatable hinge leaf 14 to traverse arc a 1 as door D is pushed to the full open position (approximately 110 degrees).
The dimensions referenced as preferred herein above are understood as one preferred configuration herein, and are not intended to be dimensions which are limiting in any way to other suitable configurations, door and jam configuration and/or weight of the applicable door being supported.
Alternatively, referring to FIG. 5 . 4 . 1 , there is illustrated a side view of control motion hinge 10 shown in a hinge extreme full-open position parallel wall B. Preferably, as door D is pushed to extreme full open arc a 2 (approximately 180 degrees; however, arc a 2 may be between approximately 130 degrees and 200 degrees,) and rotatable hinge leaf 14 rotates still further about rotatable hinge pin 17 of offset knuckle 18 . 3 (similarly with 18 . 1 , 18 . 2 not shown) of rotatable hinge leaf 14 about offset knuckle 19 . 1 and 19 . 2 of link 21 , which still further rotates link about stationary hinge pin 16 of offset knuckle 18 . 5 (similarly with 18 . 4 not shown) of stationary hinge leaf 12 about offset knuckle 19 . 3 A and 19 . 3 B of link 21 , which is maximum torsional rotation primary force f applied to first torsion spring 82 ; and thus allows roller 32 to temporarily depart from roller path 34 in an arc a 3 about the center-point of stationary hinge pin 16 .
It is contemplated herein that first torsion spring 82 is preferably configured to enable rotatable hinge leaf 14 to traverse arc a 2 as door D is pushed to the extreme full open position (approximately 180 degrees).
Hinge Close Cycle
Referring again to FIG. 5.4 , when door D is pushed to full open position (as shown) and in this position door D preferably is held in a hold-open position until door D is nudged closed wherein roller 32 traverses back past neutral point 52 , which releases force f of flat spring 22 , which results in roller 32 to traverse from hold-open ramp 54 to neutral point 52 to roller stop 38 of closing ramp 31 in a direction toward the center-point of stationary hinge pin 16 , which further causes rotatable hinge leaf 14 to return along arc a 1 until geometric plane 41 of rotatable hinge leaf 14 and stationary hinge leaf 12 contact or come in close proximate contact with one another.
Referring now to FIG. 5.5 , preferably when door D is in the closed position the weight of door D may place pull away force fd on flat spring 22 causes door D to possibly sag (door D pulls away and tilts down via pull away force fd as shown in FIG. 1 ); however, interior lip 19 of offset knuckle 18 . 5 (similarly with 18 . 4 not shown) combines with force f applied by flat spring 22 to prevent sag in door D and/or to prevent roller 32 from traversing roller path 34 . Moreover, roller 32 preferably is cradled in a pocket formed by roller stop 38 of roller path 34 and bottom edge 19 of offset knuckle 18 . 5 to hold rotatable hinge leaf 14 and stationary hinge leaf 12 in the shown closed position countering pull away force fd on door D.
It is contemplated that lengths L 1 , L 2 , L 3 , L 4 , a, and/or a 1 may be modified or one or more combinations may be modified to achieve increased force f, more or less door closing power, and/or to prevent sag of door D.
It is further contemplated that roller path 34 may be configured to have straight line(s) with or without sharp corners, or other contours, curves, and/or lengths to accomplish motions set forth herein or further contemplated for alternative control of motion hinge 10 .
It is contemplated that flat spring 22 may be modified, sized, derived from different materials and/or configured to achieve increased force and/or more or less door closing power.
It is contemplated that stationary hinge leaf 12 and rotatable hinge leaf 14 may flip positions.
Referring now to FIGS. 6 , 6 . 1 , and 6 . 2 , by way of example, and not limitation, there is illustrated a series of side views of control motion hinge 10 in motion, in accordance with an alternate embodiment of the present invention. Referring again to FIG. 6.1 , there is illustrated a side view of control motion hinge 10 , included is dampener 60 shown in a hinge-closed position with door D closed against jam J. Preferably, jam J is fitted with housing tube 65 offset from control motion hinge 10 and connected to jam J on first end 69 of housing tube 65 and approximately centered in jam J and preferably positioned along jam J other than where assembly H 1 , H 2 , and H 3 (as shown in FIG. 1 ) are located. Housing tube 65 preferably is ¾ inch in diameter, wherein such diameter hole is correspondingly drilled or otherwise defined into jam J to the preferred depth of 1.5 to 3 inches or alternatively into door D if stationary hinge leaf 12 and rotatable hinge leaf 14 flip positions. Jam J preferably includes hole 73 bored into jam J where housing tube 65 is positioned therein. Moreover, dampener 60 preferably includes plunger 62 and coil spring 64 . Preferably, plunger of dampener 60 passes in and out of housing tube 65 through which plunger 62 and plunger 62 preferably connects to coil spring 64 (shown in a compressed mode in FIG. 6.1 ) to smooth out or dampen the shock impulse and dissipate the kinetic energy of door D when closing. Housing tube 65 and plunger 62 are further preferably manufactured from aluminum, however, steel, plastic, fiberglass or other suitable material having characteristics, such as durability, water-resistance, lightweight, or the like, capable of providing structure to housing tube 65 and plunger 62 .
Referring again to FIG. 6.2 , there is illustrated a side view of control motion hinge 10 included is dampener shown in a hinge-open position with door D swung open from jam J. Plunger 62 preferably includes on one end striker head 61 and on the other end compression head 63 and travels in and out of housing tube 65 via rod seal 72 . Compression head 63 of plunger 62 is preferably attached to first end 66 of coil spring 64 and second end 67 of coil spring 64 is preferably attached to second end 68 of housing tube 65 , and housed therein. Moreover, coil spring 64 (shown in an expanded mode with rod 62 extends through hole 72 in FIG. 6.2 ) is preferably manufactured from hardened steel, however, stainless steel, plastic, or other suitable material having characteristics, such as shape memory, resistance, lightweight, or the like.
During door D closure cycle, rotatable hinge leaf 14 preferably returns along arc a 1 until geometric plane 41 of rotatable hinge leaf 14 contacts striker head 61 and transfers the kinetic energy of rotating door D to compression head 63 , which preferably is absorbed by coil spring 64 within housing tube 65 , resulting in geometric plane 41 of rotatable hinge leaf 14 preferably pushes plunger 62 towards second end 68 of housing tube 65 and compresses coil spring 64 , wherein rotatable hinge leaf 14 gently contacts or comes in close proximate contact with geometric plane 41 of stationary hinge leaf 12 for a soft closure of door D.
It is contemplated that dampener 60 may be configured as any dashpot or shock absorber whether pneumatic or hydraulic having common form of a cylinder with a sliding piston inside wherein the cylinder is filled with a fluid (such as hydraulic fluid) or air and designed to smooth out or dampen shock impulse, and dissipate kinetic energy or other known dampener known by one of ordinary skill in the art.
It is recognized that dampener 60 may be integrated within stationary hinge leaf 12 , rotatable hinge leaf 14 , or alternatively in door D.
It is further recognized that dampener 60 may encompass the features and functionality set forth in U.S. Non-provisional Application entitled “Door Hinge with a Hidden Closure System,” having assigned Ser. No. 12/012,690, filed on Feb. 4, 2008, incorporated herein by reference in its entirety.
Alternate Hinge Open Cycle
Referring now to FIGS. 7 , 7 . 1 , 7 . 2 , 7 . 3 by way of example, and not limitation, there is illustrated a series of side views of control motion hinge 10 in a door D open motion, in accordance with an example embodiment. Referring again to FIG. 7.1 , there is illustrated a side view of control motion hinge 10 with the hinge beginning-to-open position. Preferably, as door D is pushed open rotatable hinge leaf 14 rotates about rotatable hinge pin 17 , which further rotates link 21 about stationary hinge pin 16 of stationary hinge leaf 12 ; thus, an open motion of door D preferably begins to load first torsion spring 82 , which further results in an increased opposite force f of first torsion spring 82 to return rotatable hinge leaf 14 to it's original position (shown in FIG. 5.1 ). Second torsion spring 92 preferably floats with no pre-load during this phase of beginning-to-open position of door D.
Referring again to FIG. 7.2 , there is illustrated a side view of control motion hinge 10 shown with the hinge near-full-open position (neutral position). Preferably, as door D is pushed to near-full-open position (approximately 110 degrees; however, may be between approximately 100 degrees and 130 degrees,) and rotatable hinge leaf 14 rotates still further about rotatable hinge pin 17 of link whereby second end 93 of second torsion spring 92 engages roller 35 . 1 . Preferably, as door D is pushed open rotatable hinge leaf 14 rotates about rotatable hinge pin 17 , which further rotates link 21 about stationary hinge pin 16 of stationary hinge leaf 12 ; thus, a further open motion of door D preferably continues to load first torsion spring 82 , which further results in an increased opposite force f of first torsion spring 82 to return rotatable hinge leaf 14 to it's original position (shown in FIG. 5.1 ). Moreover, the same further open motion of door D preferably begins to load second torsion spring 92 , which further results in an increased opposite force f of second torsion spring 92 to return rotatable hinge leaf 14 to it's original position (shown in FIG. 5.1 ). Preferably, second torsion spring 92 functions as a torsional force such as secondary force f between rotatable hinge leaf 14 and roller 35 . 1 when door D is pushed to near-full open position (approximately 110 degrees; however, this may be between approximately 90 degrees and 130 degrees). If door D is released or nudged toward closure from its near-full-open position second torsion spring 92 assists first torsion spring 82 to softly close door D. It is recognized herein that second torsion spring 92 enables the return rotatable hinge leaf 14 to its original position (shown in FIG. 5.1 ) i.e. door D reaches full closure. The alternative non-combination torsion spring is if first torsion spring 82 is undersized, which results in door D not reaching full closure or still another alternative is if first torsion spring 82 is oversized, which results in door D having a hard loud close.
Referring again to FIG. 7.3 , there is illustrated a side view of control motion hinge 10 shown in a hinge extreme-full-open position. Preferably, as door D is pushed to extreme full open position (approximately 180 degrees; however, may be between approximately 130 degrees and 200 degrees or more,) rotatable hinge leaf 14 rotates about rotatable hinge pin 17 , which still further rotates link 21 about stationary hinge pin 16 of stationary hinge leaf 12 ; thus, an extreme open motion of door D preferably continues to load first torsion spring 82 , which further results in an increased opposite force f of first torsion spring 82 to return rotatable hinge leaf 14 to its original position (shown in FIG. 5.1 ). Moreover, second torsion spring 92 preferably floats with no pre-load during this phase of extreme-full-open position of door D. Still further, roller 32 departs from roller path 34 during extreme open motion of door D and the counter leaver action of rotatable hinge leaf 14 , link 21 , and stationary hinge leaf 12 works without roller 32 being in contact with roller path 34 when door D is pushed to extreme-full-open position. Referring again to FIG. 7.3 , when door D is pushed to extreme-full-open position (as shown) door D preferably is held in a hold-open position until door D is nudged closed. Second torsion spring 92 preferably floats with no pre-load during this phase of extreme-full-open position of door D.
Alternate Hinge Close Cycle
Referring now to FIGS. 7 , 7 . 5 , 7 . 6 by way of example, and not limitation, there is illustrated a series of side views of control motion hinge 10 in a door D close motion, in accordance with an example embodiment. Referring again to FIG. 7.2 when door D is pushed to near-full-open position (as shown) and released rotatable hinge leaf 14 rotates clock-wise about rotatable hinge pin 17 of link 21 and link 21 rotates clock-wise about stationary hinge pin 16 of stationary hinge leaf 12 under the primary force f of first torsion spring 82 and the secondary force f of second torsion spring 92 to return rotatable hinge leaf 14 to it's original position (shown in FIG. 5.1 ). Moreover, second end of second torsion spring 92 maintains contact with roller 35 . 1 to provide secondary force f of second torsion spring 92 to return rotatable hinge leaf 14 to its original position, and to enable soft closure of door D.
Referring again to FIG. 7.3 , when door D is pushed to full open position (as shown) and in this position door D preferably is held in a hold-open position until door D is nudged closed. Referring again to FIG. 7.5 there is illustrated a side view of control motion hinge 10 shown with the hinge returning to closed position. Preferably, as door D is nudged or pushed closed from the extreme-full-open position of door D rotatable hinge leaf 14 rotates clock-wise about rotatable hinge pin 17 of link 21 and link rotates clock-wise about stationary hinge pin 16 of stationary hinge leaf 12 under the primary force f of first torsion spring 82 to return rotatable hinge leaf 14 to it's original position (shown in FIG. 5.1 ). Moreover, second end 93 of unloaded second torsion spring 92 tucks in behind roller 35 . 1 to enable soft closure of door D.
Referring again to FIG. 7.6 there is illustrated a side view of control motion hinge 10 shown with the hinge in the closed position. Here, first torsion spring 82 and second torsion spring 92 are preferably configured with no pre-load during this phase of closed position of door D.
It is contemplated herein that terminology of hinge leaf or leaf hinge is interchangeable herein.
The foregoing description and drawings comprise illustrative embodiments. Having thus described exemplary embodiments, it should be noted by those skilled in the art that the disclosures within are exemplary only, and that various other alternatives, adaptations, and modifications may be made within the scope of the present disclosure. Many modifications and other embodiments will come to mind to one skilled in the art to which this disclosure pertains having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. Although specific terms may be employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation. Accordingly, the present disclosure is not limited to the specific embodiments illustrated herein, but is limited only by the following claims. | A control motion hinge, comprising a first leaf hinge with three knuckles to secure a first pin, wherein the two outer knuckles have roller knuckles, a link having a two knuckles on a first end to interlock with the first leaf hinge and a single knuckle on a second end, a second leaf hinge with two knuckles to secure a second pin when interlocked with the second end of the link, wherein the two knuckles of the second leaf hinge have a roller path for engaging the roller of the first leaf hinge, wherein such rollers traverse the roller path, a first spring device positioned between said first leaf hinge and said link to apply a force therebetween, and thus softly closing the door reducing the sound of closure during the final approach of the door. | 4 |
FIELD OF THE INVENTION
This invention relates to a method of dissociating gas hydrates, specifically natural gas and other hydrate-forming gases, into their constituent chemical species, namely the hydrate-forming gas and water, and apparatus therefor.
BACKGROUND OF THE INVENTION
Gas hydrate is a special type of inclusion compound which forms when light hydrocarbon (C 1 —C 4 ) constituents and other light gases (CO 2 , H 2 S, N 2 etc) physically react with water at elevated pressures and low temperatures. Natural gas hydrates are solid materials and they do not flow readily in concentrated slurries or solid forms. They have been considered as an industrial nuisance for almost sixty years due to its troublesome properties of flow channel blockage in the oil/gas production and transmission systems. In order to reduce the cost of gas production and transmission, the nuisance aspects of gas hydrates has motivated years of hydrate inhibition research supported by oil/gas industry. (Handbook of Natural Gas, D. Katz etc., pp. 189-221, McGraw-Hill, N.Y., 1959; Clathrate Hydrates of Natural Gases, E. D. Sloan, Jr. Marcel Dekker, Inc. 1991). The naturally occurring natural gas hydrates are also an interest as an alternative energy resource for the industry. (International Conferences on Natural Gas Hydrates, Editors, E. D. Sloan, Jr., J. Happel, M. A. Hnatow, 1994, pp. 225-231-Overview: Gas Hydrates Geology and Geography, R. D. Malone; pp. 232-246-Natural Gas Hydrate Occurrence and Issues, K. A. Kvenvolden).
Since natural gas hydrates contain as much as 180 standard cubic feet of gas per cubic foot of solid natural gas hydrates, several researchers have suggested that hydrates can be used to store and transport natural gases. (B. Miller and E. R. Strong, Am. Gas. Asso. Mon 28(2), 63-1946). The high concentration of gas in the hydrates have led researchers to consider intentionally forming these materials for the purpose of storing and transporting natural gases more cost/effectively and safely. U.S. Pat. No. 5,536,893 to Gudmundsson discloses a multi-stage process for producing natural gas hydrates. See also Gudmundsson et al., “Transport of Natural Gas as Frozen Hydrate”, ISOPE Conf. Proc., V1, The Hague, NL, June, 1995; “Storing Natural Gas as Frozen Hydrate”, SPE Production & Facilities, Feb. 1994.
U.S. Pat. No. 3,514,274 to Cahn et al. teaches a process in which the solid hydrate phase is generated in one or a series of process steps, then conveyed to either storage, or directly to a marine transport vessel requiring conveyance of a concentrated hydrate slurry to storage and marine transport. Pneumatic conveyance of compressed hydrate blocks and cylinders through ducts and pipelines has also been proposed. See Smirnov, L. F., “New Technologies Using Gas Hydrates”, Teor. Osn. Khim. Tekhnol., v 23(6), pp. 808-22 (1989), application WO 93/01153, Jan. 21, 1993.
Based upon the published literature (E. D. Sloan, 1991 Clathrate Hydrates of Natural Gases, Marcel Dekker), transporting of a concentrated gas hydrate slurry in a pipe from stirred-tank vessel would appear to be incompatible with reliable operation, or even semi-continuous operation. The blockage of pipes, and fouling of the reactors and mixing units are the critical issues. The searching of chemical/mechanical method to prevent gas hydrate blockage/fouling is still the focus of the current gas hydrate research. (Long, J. “Gas Hydrate Formation Mechanism and Kinetic Inhibition”, PhD dissertation, 1994, Colorado School of Mines, Golden, Colorado; E. D. Sloan, “The State-of-the-Art of Hydrates as Related to the Natural Gas Industry”, Topical Report GRI 91/0302, June, 1992; Englezos, P., “Clathrate Hydrates”, Ind. Eng. Chem. Res., V32, pp. 1251-1274, 1993).
Gas hydrates are special inclusion compounds having a crystalline structure known as a clathrate. Gas molecules are physically entrapped or engaged in expanded lattice of water network comprising hydrogen-bonded water molecules. The structure is stable due to weak van der Waals' between gas and water molecules and hydrogen-bonding between water molecules within the cage structures. Unit crystal of structure I clathrate hydrates comprise two tetrakaidecahedron cavities and six dodecahedron cavities for every 46 water molecules, and the entrapped gases may consist of methane, ethane, carbon dioxide, and hydrogen sulfide. The unit crystal of structure II clathrate hydrates contain 8 large hexakaidecahedron cavities and 16 dodecahedron cavities for every 136 water molecules.
Clathrate hydrates occur naturally in permafrost or deep-ocean environments, thus are considered an important natural resource. Utilizing such a resource requires understanding of gas hydrate formation and dissociation. “Kinetics of Methane Hydrate Decomposition,” Kim et al., Chemical Engineering Science, Vol. 42, No. 7, pp.1645-1653 (1987) discusses the kinetics of methane hydrate decomposition, indicating that pressure dependence further depends on the difference in gas fugacities at equilibrium pressure and decomposition pressure. “A Multi-Phase, Multi-Dimensional, Variable Composition Simulation of Gas Production from a Conventional Gas Reservoir in Contact with Hydrates,” Burshears et al., Unconventional Gas Technology Symprouis of the Society of Petroleum Engineers, pp. 449-453 (1986), discusses dissociation of hydrates by depressurization without an external heat source. “Hydrate Dissociation in Sediment” Selim et al., 62d Annual Technical Conference and Exhibition of the Society of Petroleum Engineers, pp. 243-258 (1987) relates rate of hydrate dissociation with thermal properties and porosity of the porous media. “Methane Hydrate Gas Production: An Assessment of Conventional Production Technology as Applied to Hydrate Gas Recovery,” McGuire, Los Alamos National Laboratory, pp.1-17 (1981) discusses feasibility of hydrate gas production by both thermal stimulation and pressure reduction. “Gas Hydrates Decomposition and Its Modeling”, Guo et al., 1992 International Gas Research Conference, pp. 243-252 (1992), attributes difference in chemical potential as the driving force for hydrate dissociation.
U.S. Pat. No. 2,375,559 to Hutchinson et al., entitled “Treatment of Hydrocarbon Gases”, discloses a method of forming hydrates by cooling and dispersing the components when combining the components. Similarly, U.S. Pat. No. 2,356,407 to Hutchinson, entitled “System for Forming and Storing Hydrocarbon Hydration”, discloses hydrate formation using water and a carrier liquid. U.S. Pat. No. 2,270,016 to Benesh discloses hydrate formation and storage using water and alcohol, thereby forming blocks of hydrate to be stored.
U.S. Pat. No. 3,514,274 to Cahn et al. discloses transportation of natural gas as a hydrate aboard ship. The system uses propane or butane as a carrier. U.S. Pat. No. 3,975,167 to Nierman discloses undersea formation and transportation of natural gas hydrates. U.S. Pat. No. 4,920,752 to Ehrsam relates to both hydrate formation and storage wherein one chamber of a reservoir is charged with hydrate while another chamber is evacuated by decomposition of hydrate into gas and ice.
Hydrates, much like ice, are good insulators. The process taught in the Cahn et al. '274 patent, stores hydrates in a liquid hydrocarbon slurry, thus enabling the liquid hydrocarbon handles to act as a heat transfer agent. But storing and transporting hydrates in their solid form is inherently more efficient because without the liquid component of the slurry, more natural gas (in its hydrate form) can be stored in a given volume.
In recovering gas from gas hydrate, it is also economically advantageous to maintain the above volumetric efficiency, thus favoring minimization of the volume of heat transfer agent needed to supply the hydrate's large heat of dissociation (410 kJ/kg for methane hydrate, approximately 25% higher than ice's heat of melting. Ref: Clathrate Hydrates of Natural Gases, E. D. Sloan, Jr. Marcel Dekker, Inc. 1991).
SUMMARY OF THE INVENTION
Microwave radiation is widely used in both scientific, industrial, and residential applications to efficiently transfer energy to materials containing liquid water. Oil and gas industry examples include: core measurements of permeability and fluid saturation (Ref: Parsons, 1975, Brost et al., 1981, Parmerswar et al., 1992), and oil-water emulsion-breaking in petroleum production (Ref: Oil & Gas Journal, Dec. 2, 1996). Hydrates adsorb excess water (ibid), and adsorbed water molecules can retain liquid-like properties, even at temperatures below 0° C. (Schwann, H. P., Ann. New York Academy of Science v. 125, p. 344, October 1965). The present invention utilizes microwave irradiation of gas hydrates as an efficient route for dissociating hydrates and recovering the resulting gas.
The present invention provides a process for continuously dissociating gas hydrate into its chemical constituents, namely the hydrate-forming gas (e.g. natural gas mixtures), water, plus any other impurities, and comprising the steps of:
(a) providing a clathrate hydrate within an occupying zone;
(b) positioning a source of electromagnetic radiation within said clathrate hydrate occupying zone;
(c) recovering gas from said clathrate hydrate by applying electromagnetic radiation from said electromagnetic radiation source of step (b) to said clathrate hydrate at a frequency within the range of from direct current to visible light at energy density sufficient to dissociate said clathrate hydrate to evolve its constituent gas.
The electromagnetic radiation used in the process of the invention is preferably non-ionizing radiation. The electromagnetic radiation may be suitably directed to a surface of said gas hydrate with a hollow waveguide. Useful frequencies typically include from about 100 Mhz to about 3000 Ghz. The electromagnetic radiation is characterized by wavelength of from about 0.1 mm to about 3 m.
The frequency of the electromagnetic radiation is preferably adjusted to optimize the depth of penetration in the gas hydrate, as dictated by the spatial extent of the hydrate mass to be dissociated. The radiation frequency is also preferably adjusted to optimize the efficiency of energy transfer to the hydrate mass, which is known to be a function of temperature and impurity concentration for several materials (“Microwave Technology”, in V. 16 of Kirk-Othmer's Encyclopedia of Chemical Processing, 4th Ed., Marcel Dekker, 1995).
Radiation power level is preferably adjusted to achieve an economically favorable balance between hydrate dissociation rate and efficiency reduction due to concurrent irradiation of free water produced by hydrate dissociation. The liquid water produced from said gas hydrate dissociation may be either disposed, collected and/or held in contact with the solid hydrate during the natural gas recovery steps. In some applications, however, where the water content of the recovered gas stream is necessarily low (e.g. fuel), excessive irradiation of the liquid water may heat the said liquid water sufficiently to increase the water content of the gas stream. In such a scenario, the economic efficiency of the gas recovery process decreases because downstream gas dewatering capital is required.
The process preferably further includes controlling the directing step to irradiate said gas hydrate in preference to said collected liquid water. In the case of irradiating a large hydrate accumulation (e.g. ship or barge hold), the microwave source may be positioned above the hydrate mass and direct the radiation downward. Natural gas hydrates, which are positively buoyant with respect to water, will tend to float on the produced liquid water, reducing the rate of cocurrent irradiation of the said liquid water.
The microwave source may either be stationary or movable. For example, the motion of the microwave source may be controlled by a device capable of sensing the difference in optical reflectance (i.e. albedo) between liquid water and gas hydrate. Alternatively, the microwave source may be designed to translate or rotate in such a manner that a desired region of space is irradiated. Finally, the microwave source may be positioned within the hydrate mass to provide localized irradiation.
The present invention concerns a method for the recovery of water and hydrate forming gases from storage stable gas hydrates. Hydrate-forming gases include: CO 2 , H 2 S, natural gas and associated natural gas, just to mention a few. However, in the following, natural gas is in general described as the gaseous component in the recovery process, but it should be evident that a person skilled in the art can apply the principle of the invention to consider hydrate forming gases other than natural gas, and the invention should for that reason not be regarded as limited to use of natural gas only. The present method for recovery of gas from gas hydrates can be adapted to both onshore and offshore operation. The present method may be used in conjunction with gas-from-hydrate recovery methods that exploit other modes of energy transfer (e.g. conduction, convection, mechanical, acoustic, etc.). The present method may be used in the presence of solid, liquid, or gaseous materials co-occupying the gas hydrate containing zone; these said materials may or may not act as agents in the other said gas recovery methods noted above.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a simplified schematic diagram showing major processing steps in one embodiment of the invention, namely gas recovery from hydrates in a storage zone (e.g. hold of a ship or barge).
FIG. 2 is a simplified schematic diagram showing major processing steps in one embodiment of the invention, namely dissociating a hydrate blockage in a pipeline.
FIG. 3 is a simplified schematic diagram showing major processing steps in one embodiment of the invention, namely in-situ dissociation of hydrates within a petroleum-bearing rock formation in the vicinity of a production well.
FEEDSTOCKS FOR PRODUCING HYDRATES
The present invention recovers gas from hydrates. As noted above, hydrates can be produced commercially using suitable hydrate-forming gases together with an appropriate source of water. Examples of useful sources of water include fresh water from a lake or river as well as salt water (e.g. sea water from the ocean) and any water contaminated by particulates or other materials, such as formation water from oil production. The hydrate-forming gas feedstock may comprise pure hydrocarbon gases (C 1 —C 4 ), natural gas mixtures, and other hydrate forming gases such as oxygen, nitrogen, carbon dioxide and hydrogen sulfide and their respective mixtures. The gas may be contaminated by other impurities, such as particulate and other non-hydrate forming materials or compounds.
DESCRIPTION OF EMBODIMENTS
The process of this invention recovers gas from a gas hydrate and requires no addition of liquid hydrocarbon for the purpose of heat or mass transfer. In preferred embodiments, the gas hydrate contains less than about 10 wt. % of liquid hydrocarbon, more preferably less than about 1 wt. % liquid hydrocarbon. In particularly preferred embodiments, the gas hydrate is a finely divided solid which is substantially dry.
Three particularly preferred embodiments of the current invention include processes for: (a) recovering gas from storage zone containing gas hydrates, e.g. the hold of a ship or barge, or any other stationery or movable storage zone; (b) recovering gas from a hydrate accumulation inside a gas-transporting pipeline; and (c) recovering gas from a hydrate-bearing rock formation in the vicinity of an oil and/or gas production wellbore.
FIRST EMBODIMENT
Recovery of gas from a storage zone containing gas hydrates
Temperature, ° C.
Typical
More
Pressure, kPa
Process
Pre-
Pre-
Pre-
More
Conditions
Useful
ferred
ferred
Useful
ferred
Preferred
Natural Gas
−40 to
−30 to
−20 to
100 to
100 to
102.5 to
Recovery
+40° C.
+25° C.
+10° C.
500
300
200
from
Hydrates
Desirable recovery process temperatures are set by balance between desired gas recovery rate, initial temperature of hydrate mass in zone, and temperature of high-temperature heat sink (ambient). Recovery process temperatures are set by balance between desired gas recovery rate, and materials limitations of storage zone. It is also desirable to keep the zone pressure below that of hydrate equilibrium pressure at a given temperature in order to prevent spontaneous reformation of gas and water into hydrates.
Now referring to FIG. 1, a hydrate mass 100 occupies the interior of a storage tank's inner wall 101 . The latter is separated from the outer wall 102 by a layer of insulation 103 . Strengthening members 104 connecting the inner wall 101 to the outer wall 102 impart mechanical strength to the overall tank. Attached to inner top surface of the tank is an x-y positioner 105 . Furthermore, this x-y positioner can be raised or lowered vertically, i.e. the z-direction. Attached to the x-y positioner 105 are one or more microwave generators 200 (e.g. Klystron) that receive a DC electrical signal from cables 201 that penetrate the upper surface of the storage tank walls 101 , 102 . Microwaves 203 a are passed through a hollow wave guide 202 , then targeted at the hydrate mass 100 by way of a horn-type antenna 203 . The cables 201 are connected to a D.C. power supply (not shown).
Attached to the horn-type antenna is a visible light source 300 , and an optical sensor 301 . The light source 300 directs visible light onto the hydrate surface, a fraction of which is reflected back to the sensor 301 . Digital or analog signals from the sensor 301 are processed by a computer 302 in order to measure the hydrate and/or water content of the zone that is in the microwave antenna's line-of-sight. The computer 302 then transmits digital or analog signals to the x-y positioner 105 , and the microwave generator 200 , thus concentrating microwave energy on the hydrate mass, rather than pools or zones of liquid water 400 produced by hydrate dissociation.
Liquid water 400 produced during the gas recovery process may be left in contact with the hydrate mass 100 . Because liquid water is denser than natural gas hydrates (Ref: E. D. Sloan “Clathrate Hydrates of Natural Gases”, Marcel Dekker, 1991), it will tend to occupy the bottom of the tank, providing flotation to the remaining hydrate. Alternatively, some or all of the liquid water 400 may be withdrawn from the tank by a pump 401 . The portion of the water withdrawn from the storage tank may either be stored elsewhere, or treated (if necessary) and disposed to the ambient without environmental risk.
Gas 402 , produced during the gas recovery process accumulate at the top of the storage tank. This gas is transparent to microwaves and exits the top storage tank through vents 403 connected to a pipe manifold 404 . The pipe manifold 404 directs recovered gas to downstream dewatering and recompression equipment (not shown).
SECOND EMBODIMENT
Recovery of gas from a hydrate accumulation within a pipeline
This embodiment is distinct from the first embodiment described above in that the hydrate-containing zone is a pipeline used to transport natural gas with or without other gaseous components such as CO 2 and H 2 S, with or without fluids such as natural gas liquids, crude or refined petroleum, or water.
Temperature, ° C.
Typical
More
Pressure, kPa
Process
Pre-
Pre-
Pre-
More
Conditions
Useful
ferred
ferred
Useful
ferred
Preferred
Natural Gas
−40 to
−30 to
−20 to
100 to
100 to
102.5 to
Recovery
+40° C.
+25° C.
+10° C.
70,000
30,000
200
from
Hydrates
Gas recovery temperature is set by available temperature in the pipeline. Likewise, recovery pressure is set by available pipeline pressure. Preferably, pressure in the section of the pipeline containing the hydrate accumulation is reduced to a level below the gas hydrate equilibrium pressure to avoid spontaneous formation of hydrate. Otherwise, the gas recovery process must be operated intermittently or continuously to prevent hydrate re-accumulation.
Now referring to FIG. 2, a hydrate mass 110 partially or completely obstructs a pipeline 111 . A track-mounted buggy 210 is introduced into the pipeline through a convenient access port (not shown). The buggy 210 supports a microwave generator 211 . Microwave radiation 212 is transferred from the generator 211 , through a waveguide 213 , and directed onto the hydrate mass by way of a horn antenna 214 . The antenna may be mounted at an acute angle relative to the axis parallel to the pipeline, and may be configured such that a motor drive 215 spins the antenna. In this way, the entire hydrate accumulation may be dissociated.
A power cable 216 transmit DC electrical signals to power the buggy 210 , motor drive 215 and microwave generator 211 , and a buggy-mounted, lighted video camera 217 . The camera 217 allows operators to view the vicinity of the pipeline ahead of the buggy; video camera signals are transmitted to operators by way of a coaxial cable 218 . The power cable 216 and coaxial cable 218 exit the pipeline through a pressure-tight access port (not shown).
Liquid water 310 and natural gas 311 produced during the recovery process are allowed to accumulate within the pipeline. Alternatively, the said liquid water 310 may be withdrawn from a blow-down valve 312 .
THIRD EMBODIMENT
Recovery of gas from a hydrate-bearing rock formation
This embodiment is distinct from the first and second embodiments described above in that hydrates occupy the pore spaces of a rock formation in a petroleum reservoir. The rock formation of interest is near a wellbore.
Temperature, ° C.
Typical
More
Pressure, kPa
Process
Pre-
Pre-
Pre-
More
Conditions
Useful
ferred
ferred
Useful
ferred
Preferred
Natural Gas
−40 to
−30 to
−20 to
100 to
100 to
102.5 to
Recovery
+40° C.
+25° C.
+10° C.
70,000
30,000
200
from
Hydrates
Gas recovery pressure and temperature are set by that of the petroleum reservoir and the wellbore.
Now referring to FIG. 3, a rock formation containing hydrates 120 surrounds a perforated wellbore casing 121 . A downhole tool 220 is connected to the drilling platform (not shown) by a wireline 225 , and is positioned in the hydrate-containing formation 120 . The downhole tool 220 supports a microwave generator 221 , and one or more horn-type microwave antennas 222 designed to direct microwave radiation 223 through the wellbore casing 121 , and into the rock formation 120 . The microwave generator 221 is powered by way of a DC power supply cable 224 . Gas 320 , and water 321 , are produced like any petroleum reservoir fluid.
EXAMPLE
Gas hydrates can be intentionally produced to store and transport gases. These other gases can be commercial products or pollutants or other gas types that form in natural or industrial processes. Solid hydrate particles can be used in power stations and in processes intended for reduction of pollution. Solid hydrate particles can be used where gas has to be added in large amounts, in aquatic environments, both natural and artificial.
Gas hydrates can form spontaneously and unintentionally in gas pipelines under the correct temperature, pressure, gas composition and water content. In this situation, hydrates are undesirable as they plug pipelines and reduce their operating efficiency. Likewise gas hydrates can form spontaneously in naturally occurring petroleum reservoirs. According to a recent estimate, 700,000 Trillion Cubic Feet of natural gas, or 53% of the earth's organic carbon reserves, are in naturally-occurring hydrate deposits (Ref: Kvenvolden, K. A. in “International Conference on Natural Gas Hydrates”, E. D. Sloan et al., eds, New York Academy of Science, N.Y.C., 1994, p. 232).
Artificially-produced gas hydrates can be transported from offshore storage vessels by boat, tankers, barges or floating containers towed by tugboats to the shore. In the most preferred arrangement, hydrate particles are transferred from the storage vessels offshore through a pipeline or a mechanical conveyor to a tanker by a combination of screw conveyors and gravity feed. The tanker can, but does not need to, be able to store the particles under gauge pressure. The particles can be transported to the shore as solid cargo or in water or in a hydrocarbon based liquid. Gas that escapes from the particles during transportation can be pressurized and/or used to operate the tanker and the cooling equipment, other means to dispose the extra gas.
Hydrate particles can also be stored in underground storage rooms, such as large caverns blown in rock formations. This can be accomplished by cooling/refrigerating the underground storage cavern prior to the supply of gas hydrates, so that any naturally occurring water freezes and forms an isolating ice shell on the “vessel” walls. In this way, gas escape from the storage cavern can be prevented. Like ordinary isolated vessels, the gas hydrate produced in accordance with the invention can be stored near atmospheric pressure, as described in further detail below.
Artificially-produced gas hydrates are after the transportation pumped or transferred by other ways, such as screw conveyor from the tanker to one or several storage tanks onshore. The gas may also be recovered by in-situ onboard regassifications. The melting can be accomplished using different types of heating, e.g. with emission from a gas operated power station, or the hot water exit from the turbine engine. Cold melting water can be used as coolant for any power station, thus improve the ordinary cooling towers efficiency. When the tanker is emptied, melting water and process water can be loaded. The water can have its origin from a former cargo. The melting water will be ballast for the tanker from the shore to an offshore platform. When the tanker loads the particles at the platform, the melting water is unloaded. The vessels at the platform accept the melting water for use in the hydrate production. If desired, air may be removed from the melting water and the process water and optionally pre-treated. The air removal can be effected onshore and/or offshore. In addition, the water can be used for injection to a reservoir.
In the cases of dissociating hydrate accumulations in pipelines or reservoir rock formations, the liquid water and gas produced during the dissociation reaction will flow as any other fluid. Thus, no special handling requirements are needed.
BIBLIOGRAPHY
1. Katz, D. et al., “Handbook of Natural Gas”, pp. 189-221, McGraw-Hill, N.Y., 1959.
2. Sloan, E. D. Jr., “Clathrate Hydrates of Natural Gases”, Marcel Dekker, 1991.
3. “International Conferences on Natural Gas Hydrates”, Editors: E. D. Sloan, Jr., J. Happel, M. A. Hnatow, Sloan, E. D. Jr., J. Happel, M. A. Hnatow (eds). 1994, pp. 225-231-“Overview: Gas Hydrates Geology and Geography”, R. D. Malone; pp. 232-246-“Natural Gas Hydrate Occurrence and Issues”, K. A. Kvenvolden.
4. Miller, B., and E. R. Strong, American Gas Association Mon, v. 28 (2), p. 63-1946.
5. Gudmundsson, J. S., et al., “Transport of Natural Gas as Frozen Hydrate”, ISOPE Conf. Proc., V1, The Hague, NL, June, 1995.
6. Gudmundsson, J. S., et al., “Storing Natural Gas as Frozen Hydrate”, SPE Production & Facilities, February 1994
7. Smirnov, L. F., “New Technologies Using Gas Hydrates”, Teor. Osn. Khim.
Tekhnol., V23(6), pp. 808-22 (1989),
8. Long, J. “Gas Hydrate Formation Mechanism and Kinetic Inhibition”, PhD Dissertation, 1994, Colorado School of Mines, Golden, Colo.
9. Sloan, E. D. Jr., “The State-of-the-Art of Hydrates as Related to the Natural Gas Industry”, Topical Report GRI 91/0302, June, 1992.
10. Englezos, P., “Clathrate Hydrates”, Ind. Eng. Chem. Res., V32, pp. 1251-1274, 1993
11. Kim, H. C. et al., “Kinetics of Methane Hydrate Decomposition,” Chemical Engineering Science, Vol. 42, No. 7, pp. 1645-1653 (1987).
12. Burshears, M. et al., “A Multi-Phase, Multi-Dimensional, Variable Composition Simulation of Gas Production from a Conventional Gas Reservoir in Contact with Hydrates,”., Unconventional Gas Technology Symposium of the Society of Petroleum Engineers, pp. 449-453 (1986),
13. Selim, M. S. et al., “Hydrate Dissociation in Sediment”, 62nd Annual Technical Conference and Exhibition of the Society of Petroleum Engineers, pp. 243-258 (1987).
14. McGuire, P. L., “Methane Hydrate Gas Production: An Assessment of Conventional Production Technology as Applied to Hydrate Gas Recovery”, Los Alamos National Laboratory, pp. 1-17 (1981).
15. Guo, T. M. et al., “Gas Hydrates Decomposition and Its Modeling”, 1992 International Gas Research Conference, pp. 243-252 (1992).
16. Parsons, R. W., “Microwave Attenuation-A New Tool for Monitoring Saturations in Laboratory Flooding Experiments”, S.P.E.J., pp. 302-310, August 1975.
17. Brost, D. F. et al., “Determination of Oil Saturation Distributions in Field Cores By Microwave Spectroscopy”, SPE reprint #10110, 1981.
18. Parmerswar, R. et al., “Design and Operation of the Three-Phase Relative Permeability Apparatus (X-ray/Microwave System)”, NIPER-119, 1992.
19. Article in Oil & Gas Journal, v. 94, (49), p. 66-67, Dec. 2, 1996.
20. Schwann, H. P., Ann. New York Academy of Science, v. 125, p. 344, October 1965.
21. Osepchuk, J. “Microwave Technology”, in V. 16 of Kirk-Othmer's Encyclopedia of Chemical Processing, 4th Ed., Marcel Dekker, pp. 672-700, 1995.
22. Ref: Kvenvolden, K. A. in “International Conference on Natural Gas Hydrates”, E. D. Sloan et al., eds (New York Academy of Science, N.Y.C., 1994) p. 232. | The present invention provides a process for recovering gas from a clathrate hydrate comprising the steps of:
(a) providing a clathrate hydrate within an occupying zone;
(b) positioning a source of electromagnetic radiation within said clathrate hydrate occupying zone; and
(c) recovering gas from the clathrate hydrate by applying electromagnetic radiation from the electromagnetic radiation source of step (b) to the clathrate hydrate at a frequency within the range of from direct current to visible light at energy density sufficient to dissociate the clathrate hydrate to evolve its constituent gas. | 4 |
RELATED APPLICATIONS
[0001] This application is based on a prior copending provisional application Ser. No. 60/855,067, filed on Oct. 27, 2006, the benefit of the filing date of which is hereby claimed under 35 U.S.C. § 119(e).
BACKGROUND
[0002] Uncontrolled water supplies are readily contaminated with bacteria, viruses, and protozoa (prominent examples of which are Giardia lamblia and Cryptosporidium parvum ). These contaminants are common causes of diarrheal disease in man. Of the many pathogenic coliform bacteria, adenoviruses, and enteric viruses, Escherichia coli (or “ E. coli ”) is considered to be the general indicator of water contamination by fecal material. Most waterborne diseases are related to fecal pollution of water sources and the presence of these pathogens indicates the immediate and urgent need for the removal of undesired and potentially pathogenic microorganisms prior to human consumption.
[0003] Microorganism filtration methods are currently being developed for the removal of viruses, bacteria, and protozoa, including C. parvum and Giardia . However, most of these methods, especially those targeting viruses, lack sufficient water production rates or require unrealistic energy burdens.
[0004] Many large-scale treatment facilities that meet the purification standards of the Environmental Protection Agency (EPA) exist. Unfortunately, these technologies (such as distillation or ultraviolet exposure) are complex and unrealistically large to expect a reduction in scale necessary to meet the needs of an individual soldier in the field. Filtration and chemical treatment technologies for individual water purification also exist but suffer limitations on a pathogen-specific basis. For example, chemical treatment using common oxidants (such as chlorine and hydrogen peroxide) has proven highly effective against viruses but virtually useless against protozoan cysts, such as C. parvum . The converse is true for commercially available water filters; they can remove Cryptosporidium with little difficulty, yet fail to meet EPA removal standards for viruses and some bacteria.
[0005] What is needed is a light-weight, modular, and easily transportable way of rendering surface water potable in useful quantities without an undue energy burden.
SUMMARY
[0006] Disclosed herein are a plurality of concepts (method and apparatus) for filtering ambient water to provide potable drinking water.
[0007] A first aspect of the concepts disclosed herein is method and apparatus for combining two different filter medias so as to achieve a synergistic effect. A first of the two filter medias is a filter media that exhibits a surface charge that enables natural organic matter to be filtered based on surface charge interactions. In general, most naturally occurring organic matter exhibits a negative surface charge. Therefore, the first filter media exhibits a positive surface charge (even where the net charge for the first filter media is neutral). Magnesium oxide represents an exemplary first filter media. Significantly, viral contaminants exhibit negative surface charges, thus, such a filter media can remove viral contaminants from water. A second exemplary filter media is a disinfectant, which increases the efficacy of the filtering by enhancing a rate at which viral contaminants are deactivated. For example, while the first filter media may remove viral contaminants, the first filter media may not neutralize (i.e., kill) the viral contaminants very rapidly, meaning there is a chance that the viral contaminants may be dislodged and re-enter the water. Halogens attached to inert substrates represent exemplary disinfectants. Alone, the first filter media can remove viral contaminants, and alone, a disinfectant can kill viral contaminants. Empirical studies performed in developing this technology have indicated that when used together, a synergistic effect is achieved (that is, the two materials are more efficient used together than one would expect based on their individual effectiveness). Synergist effects of greater than 10% have been noted.
[0008] Thus, one aspect of the concepts disclosed herein is a method of filtering water using both a first filter media configured to remove natural organic matter using surface charge interactions, and a second filter media having disinfectant qualities, where there is a synergistic effect between the first and second filter medias when used in combination. Similarly, one aspect of the concepts disclosed herein is a water filter including both a first filter media configured to remove natural organic matter using surface charge interactions, and a second filter media having disinfectant qualities, where there is a synergistic effect between the first and second filter medias.
[0009] Significantly, the synergistic effect noted above enables a highly efficient portable water filter to be achieved. In the prior art, to achieve water filtration for removing viral and other contaminants, tradeoffs existed between size and efficiency. For example, high quality filtration could be achieved using relatively large filters including relatively large volumes of filter media. Small, portable filters could be achieved, but such filters generally had to sacrifice some level of efficiency to achieve a small filter. For example, ultra small pore membranes can provide quality filtration, but generally require a large pressure differential to drive water through the small pores, and the small pores can become loaded with contaminants relatively quickly (i.e., after filtering a relatively small volume of water). To achieve a portable filter suitable for providing potable drinking water for an individual, the prior art has focused on using carbon based filters, often with an additional filter media, to remove many chemical contaminants and bacteria. While such filters are useful, they are not as effective as is desired with respect to removing viral contaminants and dissolved metals. The synergistic technology noted above enables higher quality filtration to be provided in a reduced form factor filter.
[0010] Another aspect of the concepts disclosed herein is directed to technology (method and apparatus) for providing potable water with a higher than normal pH (i.e., a pH of greater than 9). Conventional drinking water standards for municipal water utilities require water to be provided to end users with a pH ranging from about 5.5 to about 8.5. While such standards are readily achievable for municipalities, achieving quality filtration and an end product with a pH ranging from about 5.5 to about 8.5 using a portable filtering technology under field conditions can be problematical. Applicants have recognized that under certain circumstances, it is more important to provide safe drinking water, albeit at a relatively high pH (water having a relatively high pH can taste bitter), than it is to provide aesthetically pleasing water. Dissolved metals can be more readily removed from water by precipitation at relatively higher pHs. Portable water purification can be greatly simplified by sacrificing the steps of reducing the pH after metals have been removed. Thus, one aspect of the concepts disclosed herein is providing a portable water filter (and method) where the pH is raised to a relatively high level (i.e., a level higher than normally associated with drinking water, such as over 9).
[0011] Still another aspect of the concepts disclosed herein is a portable water filter massing less than about 250 grams, exhibiting a pressure drop ranging from about 0.5 psi to about 5.0 psi, and being capable of providing potable water at a flow rate ranging from about 50 ml/min to about 5000 ml/min, using only gravity as a motive force, where the filter removes viral contaminants in additional to bacteria, particulates, and chemical contaminants. In general, the prior art has had to sacrifice removal of viral contaminants to achieve a filter with similar characteristics. Such a filter can be implemented using four types of filter media, including a membrane based media for removing particulates via mechanical filtration, a carbon media for removing contaminants via adsorption, a filter media for removing organic matter via surface charge interactions, and a disinfectant filter media.
[0012] In at least one exemplary embodiment, a water filter described herein is formed as a modular component to be inserted into a commercially available hydration system (for example, the CAMELBAK® hydration system). The device is inserted in-line with the hydration system drink tube via quick release fittings. The device contains a disposable cartridge insert that has a service life expectancy of up to 750 liters of filtered water. Such a water filter removes viruses using a filter media that interacts with surface charges carried by the virus, rather than by using a filter media having pore sizes smaller than the virus (note that such extremely small pore sizes increase the pressure drop exhibited by the filter).
[0013] One aspect of a filter according to embodiments described herein is that it is lightweight, having a nominal total mass of less than 250 grams. Exemplary filters massing about 190 grams have been successfully implemented.
[0014] Another aspect of a filter according to one or more of the embodiments described herein is that it has a form factor sufficiently small to be hand held, approximately the size of a small flashlight.
[0015] This Summary has been provided to introduce a few concepts in a simplified form that are further described in detail below in the Description. However, 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 determining the scope of the claimed subject matter.
DRAWINGS
[0016] Various aspects and attendant advantages of one or more exemplary embodiments and modifications thereto will become more readily appreciated as the same becomes better understood by reference to the following detailed description, when taken in conjunction with the accompanying drawings, wherein:
[0017] FIG. 1 graphically illustrates a synergistic effect on filtration efficiency noted when two filter media defined herein are used in combination;
[0018] FIG. 2 illustrates a perspective view of a filter according to a first exemplary embodiment of portable filters disclosed herein;
[0019] FIG. 3 illustrates a section view of a filter according to the first exemplary embodiment of FIG. 2 ;
[0020] FIG. 4 illustrates a schematic view of a filter according to a second exemplary embodiment of the concepts disclosed herein; and
[0021] FIG. 5 schematically illustrates the use of a holding volume to further increase filtration efficiency.
DESCRIPTION
Figures and Disclosed Embodiments are not Limiting
[0022] Exemplary embodiments are illustrated in referenced Figures of the drawings. It is intended that the embodiments and Figures disclosed herein are to be considered illustrative rather than restrictive. No limitation on the scope of the technology and of the claims that follow is to be imputed to the examples shown in the drawings and discussed herein.
[0023] As noted above, the concepts disclosed herein encompass water filters for providing potable drinking water and method of filtering water to provide potable drinking water. Significantly, the concepts disclosed herein can be used to achieve a portable water filter that can be used in conjunction with personal hydration systems. One broad aspect of the techniques disclosed herein relates to a novel combination of a first filter media and a second filter media, wherein the combination of filter media achieves a synergistic effect on filtration. A second broad aspect of the techniques disclosed herein relates to providing potable drinking water with a relatively higher pH than is generally considered acceptable. While such relatively high pH water is less aesthetically pleasing than conventional drinking water, such relatively high pH water is safe for human consumption, and such relatively high pH water can be provided using relatively small man portable water filters. A third broad aspect of the techniques disclosed herein relates to compact portable water filter that can provide potable drinking water using only gravity as a motive force, where the portable water filter can remove contaminants including bacteria, chemicals, metals, and viruses. Such a filter masses less than about 250 g, and is capable of providing a minimum flow rate of about 50 ml/min. Significantly, similarly compact prior art filters have generally been incapable of removing viral contaminants without utilizing ultra-small pore membranes, which significantly reduce achievable flow rates where gravity is providing the motive force.
[0000] Synergistic Filtration
[0024] Referring now to the first aspect of the concepts disclosed herein, applicants have identified two different filter medias, which when combined provide a synergistic effect, generally as indicated in the graph of FIG. 1 . A first filter media 10 and a second filter media 12 can be used individually to filter drinking water. Theoretically, when the first and second filter medias are used in combination (as indicated by a theoretical combined filter media 14 ), it would be expected that a relative efficiency of the combination would be equivalent to a relative efficiency of the first filter media plus the relative efficiency of the second filter media. However, in the case of the first and second filter medias identified by applicants, it has been empirically discovered that when used in combination, the first and second filter media identified by applicants provides a relatively higher filtration efficiency than would be expected (as indicated by synergistic combined filter media 16 ). Applicants have tested a variety of related first and second filter media, and found a synergistic effect of at least a 10% higher than expected filtration efficiency. In some cases, empirical data suggest that the synergistic effect can provide an improvement approaching 50%. It should be understood that the graph of FIG. 1 is intended to be exemplary of this identified synergistic effect, rather than representing specific values. Indeed, many empirical studies have indicated synergistic effect exceeds 10%. Actual details from one of these studies is provided below in Table A.
[0025] The first filter media identified by applicants is characterized by having a positive surface charge. Most natural organic matter, including viral contaminants, exhibit negative surface charges. Filter media exhibiting a positive surface charge can remove such natural organic matter and viral contaminants from water via surface charge interactions. An exemplary first filter media is magnesium oxide. It should be recognized however, that other filter media having a positive surface charge may also be suitable for use as a first filter media. A potential problem with using a first filter media by itself is that there is a possibility that some of the retained natural organic matter, particularly viral contaminants, may at some point in the filtration process become dislodged from the first filter media. Where the first filter media exhibits relatively strong disinfectant properties, viral contaminants that are attained on the first filter media for relatively short periods of times will likely be successfully deactivated (i.e., killed). However, the less effective the first filter media is with respect to being a disinfectant, the more likely it is that a viral particle retained on the first filter media will become dislodged and reintroduced into the water being filtered, before the virus particle is deactivated.
[0026] It should also be understood that the disinfectant properties of the first filter media will vary based on the type of filter media having a positive surface charge that is implemented. As noted above, magnesium oxide represents an exemplary first filter media. Magnesium oxide is available in several different grades. Some grades are more effective than other grades at raising the relative pH of the water being filtered. Viral disinfection by the magnesium oxide itself is generally more successful at higher pHs. Thus, the different grades of magnesium oxide will exhibit different disinfectant properties. If a different first filter media having positive surface charges is employed, that filter media will likely exhibit distinguishable disinfectant properties.
[0027] The second filter media identified by applicants, which when used in combination with the first filter media will provide a synergistic effect, is a filter media exhibiting relatively stronger disinfectant properties (i.e., a filter media that is a better disinfectant than the first filter media exhibiting the desired surface charge properties noted above). It appears that by employing a relatively strong disinfectant along with a filter medium that can immobilize viruses using surface charge effects improves filtration by increasing an amount of the immobilized viruses that can be deactivated in a relatively short period of time. This is significant, because it enables a relatively small amount of filter media to successfully deactivate viral contaminants in a relatively large volume of water, enabling a high-quality portable water filter to be achieved. This becomes especially true when working with very small filters with limited space for working media, and short fluid contact times when higher flow rates are desired.
[0028] Halogens bound to an inert substrate represent an exemplary second filter media. While free halogens, such as chlorine tablets, would provide a disinfectant, such a filter media would undesirably introduce an excess of halogens into the water being filtered. That is, more chlorine would be introduced into the water being filtered than would be used to deactivate the viral contaminants and organic matter in the water. This would present an additional filtration challenge, in that another layer of filter media would be required to remove the excess chlorine. Where halogens are bound to an inert substrate, the halogens are available to be used to deactivate organic matter, while being generally retained upon their inert substrate, and thus excess halogens are generally not introduced in large quantity into the water being filtered. Therefore, an additional filter layer to remove the excess halogens is not required. Halogen impregnated media is readily available (an example of which is HaloPure by HaloSource). The substrate media is generally a polymeric media which functions as a matrix for housing a reservoir of halogen that is not readily soluble in the influent water. However, when a microbe encounters the media surface, a halogen molecule is released from the polymer matrix and is absorbed by the microbe, resulting in destruction of the microbe.
[0029] Thus, the first filter media (the filter media characterized as having positive surface charges) removes viral contaminants from water, and the second filter media (characterized as having relatively strong disinfectant properties) increases the efficacy of the filtering by enhancing a rate at which viral contaminants are deactivated. Alone, the first filter media can remove viral contaminants, and alone, a disinfectant can kill viral contaminants. As noted above, empirical studies performed in developing this technology have indicated that when used together, a synergistic effect is achieved (that is, the two materials are more efficient used together than one would expect based on their individual effectiveness). Synergistic effects of greater than 10% have been noted.
[0030] Referring once again to the novel concepts disclosed herein, a filter media that removes viruses from water due to the interaction between surface charges on the virus (as opposed to a pore size smaller than the virus), is combined with at least one other filter media, to enable a variety of different contaminants to be removed from water.
[0031] It should be noted that some microbes are less easily susceptible to halogen disinfection (an example is type 2 Polio virus), thus, the magnesium oxide may deactivate materials that cannot be deactivated by the halogen aided filter media (i.e., the second filter media exhibiting relatively stronger disinfectant properties). Furthermore, some microbes are less susceptible to pH influence or electro-static capture (an example is the FR bacteriophage virus), thus, the disinfectant filter media is available to deactivate those types of microbes. By combining both filter media (i.e., the first filter media exhibiting charge surface interactions, and the second filter media exhibiting relatively stronger disinfectant properties) in a multi barrier approach, a broader spectrum of disinfection can occur than with either filter media alone.
[0032] Significantly, the synergistic effect based on combining a filter media exhibiting charge attraction properties and a filter media exhibiting disinfection properties was unexpected. It should be noted that while magnesium oxide is intended to represent an exemplary first filter media exhibiting desirable surface charge properties (meaning that other filter media exhibiting a positive surface charge could be combined with a disinfectant filter media to achieve a similar synergistic effect), the use of magnesium oxide provides additional beneficial effects, beyond the synergistic effect noted above. For example, magnesium oxide filter media is multi functional, as in addition to removing natural organic matter due to surface charge interactions, the magnesium oxide enhances metals removal by increasing the relative pH of the water being filtered (thus favoring precipitation of dissolved metals as metal hydroxides). Furthermore, it is believed that magnesium oxide represents a particularly useful first filter media due to its relatively high isoelectric point.
[0033] Magnesium oxide has an isoelectric point just over pH 11, which means for incoming water having a pH below that, the surface of the magnesium oxide will have a positive surface charge. Viruses (and bacteria) also have an isoelectric point, such that below their isoelectric point they exhibit a positive surface charge and above their isoelectric point they exhibit a negative surface charge. That point is different for different organisms. Because magnesium oxide has such an unusually high pH isoelectric point, most recognized pathogenic micro-organisms assume a negative surface charge under the influence of magnesium oxide. The negative surface charge on the microbe and the positive surface charge on the magnesium oxide cause electro-static type attraction and bonding. Further, because of the high pH environment right at the magnesium oxide surface, it is likely (but not completely proven) that the microbes are eventually killed (probably over the course of minutes or hours), unlike many other electro-static bonding materials. The fact that magnesium oxide itself exhibits some disinfectant properties is beneficial because, as noted above, some microbes are less easily susceptible to halogen disinfection (an example is type 2 Polio virus).
[0034] Magnesium oxide represents a particularly efficient first filter media (i.e., a filter media exhibiting desirable surface charge properties) where a portable and relatively small water filter is desired. Because of the short contact times and relative high flow rates required for such portable water filters, it is desirable for the filter medias employed in such a portable filter to perform “double duty” whenever possible. Where magnesium oxide is present in such a portable water filter, the magnesium oxide can increase the pH of relatively low pH influent water (such as acid rain influenced water sources or high organic (humic and tannic) acid containing influent water) by neutralizing the acids (due to magnesium oxide's basic properties). Magnesium oxide can also facilitate removal of dissolved metals. Many metals that are dissolved in solution, particularly the cationic metals, often form hydroxide precipitates at various pHs, depending on the particular metal in question. When these dissolved cationic metals in solution encounter the relatively high pH magnesium oxide surface, many will form metal hydroxides that precipitate out of solution onto the magnesium oxide surface.
[0035] The natural organic matter removal capabilities of magnesium oxide can greatly enhance the efficacy of the halogen matrix, because by reducing the amount of organic background in solution, the magnesium oxide also reduces the chemical background demand of the solution, thereby freeing up more of the halogen to disinfect microbes, instead of reacting with background organic matter. This effect also can help reduce the possible formation of tri-halo-methanes and other disinfection byproducts that may otherwise form without the magnesium oxide treatment step.
[0036] As noted above, many different grades of magnesium oxide are available. Furthermore, many different grades of halogen impregnated filter media are also available. Halogenated filter media can be obtained where the halogen comprises chlorine, bromine, or iodine. While the synergistic effect discussed above will be exhibited by combinations of these different materials, it should also be recognized that the filtering effect can be modified using careful selection of the first filter media (i.e., the filter media exhibiting the desirable surface charge properties) and second filter media (i.e., the filter media exhibiting the relatively stronger disinfectant properties). For example, if it is recognized that the water being filtered is likely to be a relatively low pH, then in the first filter media can be selected based on its ability to moderate pH (for example, some grades of magnesium oxide are able to moderate lower pH levels than other grades of magnesium oxide; and other potential first filter medias may be less able to moderate low pH levels). Thus, the ability to moderate pH may be a factor in selecting a particular first filter media. The ability to moderate the pH of the water being filtered is significant beyond simply correcting undesirably low pH levels in the water. As discussed above, a relatively higher pH can lead to relatively better metal filtration. Furthermore, the pH within the filter may also have an effect on the efficiency of the disinfectant. For example, where the disinfectant filter media is a halogenated impregnated filter media, relatively greater amounts of halogens will become available to the water being filtered as the pH within the filter is increased. Thus, if it is recognized that the water to be filtered it may be relatively more contaminated with microbes and viral contaminants than might be considered normal, it may be desirable to select a first filter media that will increase a relative pH within the filter, to ensure that relatively larger amounts of halogens are available to the water being filtered. It should be recognized that this will have the effect of exhausting the halogenated impregnated filter media at a higher rate, meaning that less water can be safely filtered given the same volume of halogenated filter media. Thus, in circumstances where the viral and microbe contamination will be relatively lower, it will be less desirable to increase the relative pH of the water within the filter, to avoid prematurely exhausting the halogenated filter media. In at least some embodiments, the first filter media and the second filter media will be mixed together, which will have the effect of increasing a relative pH proximate the halogenated filter media, thereby making more of the halogens available to the water being filtered.
[0037] Thus, even where the synergistic effect between the first filter media and the second filter media is exploited, careful selection of the first filter media and second filter media actually implemented can provide measurable differences in filtration.
[0038] As noted above, Table A provides details of one of the empirical studies, which indicates that the synergistic effect can exceed a 20% increase in filtration efficiency. The first filter media (i.e., the filter media exhibiting desirable surface charge properties) employed was magnesium oxide, and the second filter media (i.e., the filter media exhibiting a greater disinfectant properties) employed was a chlorinated filter media (HaloPure) provided by HaloSource. Both of the filter medias were tested alone, and then in combination. These tests were performed using de-ionized lab water seeded with the MS2 virus. The data has been equalized for volume of media, flow rate of water, and media/water contact time. Parameters for each test included 5.0 cubic inches of filter media, 200 ml/min flow rate, and 9.6 seconds of contact time between the relative filter media and the influent water.
TABLE A Virus Virus Log Percent Influent Effluent Virus Virus Media Type (pfu/mL) (pfu/mL) Removal Removal Magnesium Oxide 8.10 × 10 4 1.65 × 10 4 0.69 79.7 granules Chlorine impregnated 1.80 × 10 4 4.43 × 10 3 0.61 75.4 resin MgO & Chlorine resin 3.80 × 10 4 1.64 × 10 2 2.36 99.6 (50%-50%) mix Note that based on a 50/50 mixture of the filter medias, one would have calculated the removal efficiency of the mixture to be about 77.55 (one half of 79.7 plus one half of 75.4)
Portable Filter Providing Relatively High pH Drinking Water
[0039] As noted above, another aspect of the concepts disclosed herein is a portable apparatus (i.e., a water filter) directed to providing potable drinking water having a relatively higher pH than is normally associated with drinking water. Conventional drinking water ranges from about 5.5 to about 8.5 pH (based on guidelines for a municipal water utilities in the United States). Applicants have realized that these standards are based on aesthetics, rather than being based on providing water that is fit for human consumption. Applicants have further realized that there exist ambient waters containing relatively large amounts of dissolved metals which must be filtered to provide potable water. Providing a quality portable water filter to remove relatively large amounts of dissolved metals is problematical, because conventional filtration techniques would require relatively large amounts of filter media to first increase the relative pH of the water and precipitate out the dissolved metals, and then to decrease the relative pH of the water to provide filtered water ranging from about 5.5 to about 8.5 pH. Applicants have realized that eliminating the additional filter media required to decrease the relative pH of the water after the dissolved metals have been precipitated enables relatively high pH potable water to be achieved using a compact and relatively small water filter. While the relatively high pH potable water provided by such a technique does not meet normal aesthetic quality standards for drinking water, it does provide potable drinking water, and in certain circumstances, a relatively larger quantity of un-aesthetically pleasing but potable drinking water is preferable to relatively smaller quantities of aesthetically pleasing drinking water.
[0040] It should be recognized that the phrase relatively high pH potable water is intended to encompass water that is fit for human consumption and in excess of a pH of about 9. Such drinking water can be obtained by filtering ambient water using a portable water filter including a sufficient quantity of magnesium oxide to increase a pH of the ambient water to greater than about 9. Such a portable water filter will be particularly beneficial in providing potable drinking water from ambient waters containing relatively large amounts of dissolved metals. Of course, where portability of the filter is not required, larger filters including additional layers could be used to provide a more aesthetically pleasing drinking water.
[0041] Various embodiments of such a portable water filter are envisioned. In at least one embodiment, such a portable water filter includes a filter media configured to remove particulates using mechanical filtration, and a filter media configured to remove contaminants via absorption, in addition to the magnesium oxide filter media. If desired, the halogenated filter media discussed above can also be employed in such a portable water filter, to provide the synergistic effects noted above.
[0000] Portable Filter Meeting Specified Parameters
[0042] Yet another aspect of the concepts disclosed herein is a portable water filter that meets specified parameters that have been unable to be achieved using conventional filtration technology. Such a portable filter is relatively small, relatively light weight, can remove a range of the contaminants including viral contamination, and provides a flow rate sufficient to provide drinking water for an individual without requiring any motive force other than gravity. The specified parameters include a mass of less than about 250 g, a minimum flow rate of about 50 ml (optionally a maximum flow rate of about 5000 ml per minute) where the force of gravity is used to drive water through the portable water filter, and a pressure drop ranging from about 0.5 psi to about 5.0 psi.
[0043] While portable water filters massing less than about 250 g are known in the art, conventional portable water filters are generally either are not well-suited to remove viruses, or cannot meet the specified flow rates and pressure drops because they incorporate a filter member exhibiting a pore size smaller than the average size of a virus to provide adequate removal of viral contaminants.
[0044] In an exemplary embodiment, such a portable water filter can be implemented using the following filter media: 1) a membrane filter configured to remove relatively larger particles via mechanical filtration; 2) a carbon based filter media for removing contaminants via absorption; 3) a magnesium oxide based filter media to remove natural organic matter and viral contaminants via service charge interactions; and 4) a disinfectant filter media configured to enhance deactivation of viral contaminants and microbes.
[0045] It should be recognized that the following embodiments may be described in connection with a single one of the aspects discussed above, however, the following embodiments can be used to implement any of the three broad aspects of the concepts disclosed herein.
[0000] Specific Portable Filter Embodiments
[0046] Referring to FIG. 2 , a perspective view of a filter according to a first exemplary embodiment of the concepts disclosed herein is illustrated. A filter 100 has a housing 110 that is generally elongated in the direction of flow of water from an inlet coupling 122 to an output coupling 132 . It should be recognized that various types of coupling can be implemented, including but not limited to male couplings, female couplings, and threaded couplings. Where the filter is used as an inline filter for a personal hydration system, the coupling can advantageously share a coupling form factor already employed in the hydration system.
[0047] Referring to FIG. 3 , a section view (taken along section line II-II in FIG. 2 ) of filter 100 is illustrated. An inlet passage 120 extends axially from one end of elongated housing 110 and terminates at inlet coupling 122 . An outlet passage 130 similarly extends axially from the other end of elongated housing 110 and terminates at outlet coupling 132 . Water flows into the filter via the inlet passage, through the inside of housing 110 , and out via the outlet passage. The housing is advantageously formed by combining an inlet side housing shell 112 and an outlet side housing shell 114 , which are fixed together at a circumferential joint 116 . It should be recognized that such a configuration is exemplary, rather than limiting. For example, a clam shell type housing can be employed, where the clamshell joint extends either latitudinally or longitudinally.
[0048] A filter according to the exemplary embodiment of FIGS. 2 and 3 includes three different filter technologies: hollow fiber membranes, activated carbon, and a synergistic combined filter media that removes viruses and naturally occurring organic matter via surface charge interactions, and deactivates the organic matter/viruses via disinfectant action. Thus, the synergistic combined filter media includes the first filter media (i.e., a filter media exhibiting desired surface charge properties) and a second filter media (i.e., a filter media exhibiting relatively stronger disinfectant properties) discussed in detail above. As noted above, the two different filter medias exhibiting a synergistic effect on filtration can be implemented as individual homogeneous layers, or as a single layer where the two different filter medias have been mixed together.
[0049] As water flows into housing 110 , it first encounters hollow fibers 140 , which serve as a membranous filter element. The water molecules migrate from the outside surface of the hollow fibers to the hollow interior, and then outward through the hollow ends of the fibers. A seal 142 is provided at the open ends of hollow fibers 140 . Upon emerging from the hollow open ends of hollow fibers 140 , the water then flows in sequence through a layer of granulated activated carbon 160 , and combined synergistic filter media 170 .
[0050] Permeable media separators 154 , 162 , and 172 are disposed at each end of granular activated carbon layer 160 and exchange resin layer 170 , to retain the filter media layers in their relative positions within housing 110 . It should be recognized however, that mixtures of filter media can be employed in place of well defined layers. A media tension spring 150 is disposed between seal 142 and a screen 152 to apply compressive force against media separator 154 , to facilitate retention of filter media layers 160 and in their relative positions within the housing 110 . After passing through all filter media and the last media separator, the water flows through an outlet screen 174 and out of housing 110 via outlet passage 130 .
[0051] Couplings 122 and 132 are shown as being male threaded couplings; however, other types of coupling, such as Hydrolink-type couplings, can be employed. Thus, any coupling scheme may be used to insert the filter into a drinking water line. Hydrolink couplings are commonly used in the CAMELBAK® hydration systems.
[0052] With respect to joint 116 between inlet side housing shell 112 and outlet side housing shell 114 , such a joint can be configured in various ways. If it is desired for the filter to be disassembled and refilled with a fresh cartridge in the field, then joint 116 is embodied with a twist lock feature to securely, yet releasably, engage housing shells 112 and 114 with one another. On the other hand, to prevent tampering with the filters in the field, joint 116 may be permanently joined using cement, welding, or other more permanent fixation means, so that the unit can only be reloaded with a new cartridge at a manufacturer facility. Either housing configuration may be desirable depending upon security conditions in the field. Other means of joining the inlet side and outlet side housing shells together may also be used, such as threaded parts, clamps, and other ways known in the art.
[0053] It should be recognized that filter media 170 can be implemented simply by magnesium oxide, in embodiments implementing a portable water filter configured to provide relatively high pH potable drinking water, generally as discussed above.
[0054] Referring to FIG. 4 , a schematic view of a filter according to a second exemplary embodiment is illustrated. Although the form factor may vary, the second embodiment has in common with the first that it is a representation of an in-line post filter for use in a personal hydration system. Water flows into a filter 200 via an inlet passage 220 , and sequentially through five media layers 240 , 250 , 260 , 270 , and 280 , which are retained inside a housing 210 , before exiting through an outlet passage 230 .
[0055] First media layer 240 is a coarse depth-filter of polypropylene felt or foam. The function of first layer 240 is to remove visible debris and detritus, algal filaments and large silt particles by mechanical sieving action.
[0056] Second media layer 250 is a bundle of 0.2 micron hollow fiber membranes. The function of second layer 250 is to remove algae, protozoa, bacteria and general turbidity through size exclusion.
[0057] Third media layer 260 is granular magnesium oxide having a high surface area and high surface activity. The function of third layer 260 is to remove viruses, humic and other organic acids, and many heavy metals through surface charge attractions and active surface chemistries. A high surface area is considered to be greater than about 50 m 2 /g, and a high surface activity is considered to be an activity index of less than about 8 seconds.
[0058] Fourth media layer 270 is granular activated carbon. The function of fourth layer 270 is to remove a large array of dissolved organic carbon compounds, including chemical warfare agents, as well as toxic industrial chemicals, via chemical absorption.
[0059] Fifth media layer 280 is a halogenated filter media. The function of fifth layer 280 is to provide a disinfectant functionality, and to enhance the effectiveness of the filter via the synergistic effect discussed above in detail.
[0060] An optional holding volume 281 can be included if desired. The purpose of the holding volume is discussed in detail below. It should be noted that such a holding volume can be part of the filter itself, or can be implemented as a separate volume downstream of the filter outlet.
[0061] No media separators, media tension spring, or screens are shown in FIG. 4 , nor is a joint for the housing shown. These features may be added to the second embodiment in a like manner to their implementation as shown for the first embodiment, in order to gain the operational benefits they provide. However, it should be recognized that such features are not strictly necessary in order to practice the technology disclosed herein.
[0062] In studying empirical data from for the synergistic embodiment in particular, it has been recognized that the filtration effectiveness with respect to deactivating viral contaminants and microbes can be improved simply by providing a residence time chamber or holding volume. Generally as described above, a relatively small amount of the halogen will become disassociated from the halogenated filter media, and will be introduced into the water being filtered. Design of the filter will take into account how many halogen atoms will be released into the water being filtered, to ensure that the amount of halogens in the filtered water does not exceed safe limits for potable drinking water. The function of the residence time chamber or holding volume is to provide additional time for the free halogens in the water being filtered to deactivate the viral contaminants and microbes in the water that have not been retained by the magnesium oxide filter media. The design of the filter is to provide a safe drinking water that is 99.6% free (see Table A above) of viral pathogens, based on drawing water through the filter by gravity and drinking the water immediately after exits the filter. If the water is held in some reservoir for a period of time before drinking, the halogens remaining in the water will continue to deactivate microbes and viral contaminants. Empirical data has indicated that holding periods ranging from about one to about five minutes will reduce viral contamination levels to below detection limits. The size of the holding volume will be a function of how the portable water filter will be used.
[0063] FIG. 5 schematically illustrates a personal hydration system 500 , including a raw water reservoir 502 , an in-line filter 504 (generally as described above), and a holding volume 506 . Tubing 508 is provided to enable a user to draw water out of personal hydration system 500 .
[0064] It should be recognized that the size of the holding volume is entirely a function of how much filtered water should be immediately available to the user. For example, if the portable water filter will only be required to provide one or two mouthfuls of water over any five-minute period, and the holding volume can be relatively small (i.e., approximately the size of 1-2 mouthfuls of water). If it is expected that relatively larger amounts of water will be required, a relatively larger holding volume can be provided. For example, personal hydration systems generally include a tank worn over a user' back that contains anywhere from about 1 to about 3 L of water. One use of the portable filters disclosed herein is as an in-line filter for such personal hydration systems, where the portable filter is disposed in between the water reservoir and the user's mouth. It would be simple to incorporate a holding volume in between the filter outlet and a user's mouth, ranging anywhere from several milliliters to hundreds of milliliters in size. Furthermore, depending on an amount of time available for filtering, unfiltered water could be stored in a first personal hydration system, which could be coupled to a second personal hydration system via portable filters such as those described above. Over a period of time, the downstream personal hydration system would become filled with water filtered once through the portable filter. Residual halogens within that second personal hydration system would continue to reduce the amount of viral contaminants and microbes.
[0065] With respect to the various filter embodiments discussed above, it should be recognized that the ordering of layers shown in the first and second embodiments is not strictly required to practice embodiments of the technology disclosed herein. The filter may be alternatively implemented with the layers of filter media in a different order (recognizing that in some embodiments it is desirable for the two filter media which achieve a synergistic effect to be disposed in close proximity, or even intermingled into a single layer). Further exemplary water filters encompassed within the concepts disclosed herein are presented below. It should be recognized that these specific embodiments are simply exemplary, and not limiting. The membrane filter is first in order in each example. However, other layers of media are arranged in different order. While overall filter volumes can vary, in at least one preferred embodiment, the filter volume is at least as large as a mouthful of water, such that when used in a personal hydration system, the filter will include a pre-filter mouthful of water.
ADDITIONAL EXAMPLE 1
[0066] According to a first additional example, the filter is implemented with four sequential layers of filter media. The first layer is a hollow fiber membrane, which is followed in sequential order by a second layer of carbon (granular or block), a third layer of halogen impregnated beads (chlorinated or brominated), and a fourth layer of magnesium oxide.
ADDITIONAL EXAMPLE 2
[0067] According to a second additional example, the filter is implemented with four sequential layers of filter media. The first layer is a hollow fiber membrane, which is followed in sequential order by a second layer of halogen impregnated beads (chlorinated or brominated), a third layer of carbon (granular or block), and a fourth layer of magnesium oxide.
ADDITIONAL EXAMPLE 3
[0068] According to a third additional example, the filter is implemented with four sequential layers of filter media. The first layer is a hollow fiber membrane, which is followed in sequential order by a second layer of magnesium oxide, a third layer of halogen impregnated beads (chlorinated or brominated), and a fourth layer of carbon (granular or block).
ADDITIONAL EXAMPLE 4
[0069] According to a fourth additional example, the filter is implemented with four sequential layers of filter media. The first layer is a hollow fiber membrane, which is followed in sequential order by a second layer of carbon (granular or block), a third layer of magnesium oxide, and a fourth layer of halogen impregnated beads (chlorinated or brominated).
ADDITIONAL EXAMPLE 5
[0070] According to a fifth additional example, the filter is implemented with four sequential layers of filter media. The first layer is a hollow fiber membrane, which is followed in sequential order by a second layer of magnesium oxide, a third layer of carbon (granular or block), and a fourth layer of halogen impregnated beads (chlorinated or brominated).
ADDITIONAL EXAMPLE 6
[0071] According to a sixth additional example, the filter is implemented with four sequential layers of filter media. The first layer is a hollow fiber membrane, which is followed in sequential order by a second layer of halogen impregnated beads (chlorinated or brominated), a third layer of magnesium oxide, and a fourth layer of carbon (granular or block).
[0072] If desired, an antimicrobial agent can be added to the fiber membrane layer. The fiber material can be impregnated with an antimicrobial agent, which is preferably mixed with the fiber during spinning and formation of the fibers so that it is dispersed throughout the fibers and will diffuse to the surface of the fibers during use of the filter. Such fibers typically are rendered antimicrobial, either by treating them topically or by impregnating them with the antimicrobial agent during their extrusion. Exemplary concentrations of the antimicrobial agent generally ranges from about 100 to about 10,000 ppm. Exemplary agents will be practically insoluble in the water passing through the filter, and are safe, non-toxic, non-carcinogenic, non-sensitizing to human and animal skin, and will not accumulate in the human body when ingested. An exemplary antimicrobial agent will have a broad spectrum, such that it is substantially equally effective against a majority of harmful bacteria encountered in water. For example, an antimicrobial agent such as 2,4,4′-trichloro-2′-hydroxydiphenol ether, or 5-chloro-2-phenol (2,4 dichlorophenoxy), commonly sold under the trademark MICROBAN™, by Microban Products Co., represents one exemplary, but not limiting, antimicrobial agent.
[0073] As noted above, in addition to the filter media configured to remove viruses by interacting with surface charges, some embodiments will incorporate additional filter media configured to remove additional types of contaminants.
[0074] With respect to the claims that follow, it should be recognized that any reference to claim elements in the singular, for example, using the articles “a,” “an,” or “the” is not to be construed as limiting the element to the singular.
[0075] Although the concepts disclosed herein have been described in connection with the preferred form of practicing them and modifications thereto, those of ordinary skill in the art will understand that many other modifications can be made thereto within the scope of the claims that follow. Accordingly, it is not intended that the scope of these concepts in any way be limited by the above description, but instead be determined entirely by reference to the claims that follow. | A portable water filter including a plurality of different filter medias. One embodiment includes two filter exhibiting a synergistic effect on filtration. Another embodiment provides higher than normal pH water to simply removal; of dissolved metals. Still another embodiments meets specified performance parameters. The filters are usable in hand held water purifiers, gravity feed filtration systems, and personal hydration systems. The water filter is lightweight to facilitate being carried in the field by a person for extended periods. | 2 |
[0001] This application claims priority to U.S. Provisional Patent Application No. 60/914,997, filed Apr. 30, 2007 which is incorporated by reference herein in its entirety
FIELD OF INVENTION
[0002] The invention is related to methods of protecting, preventing and reducing intestinal injury in a human subject at risk for or suffering from shock, hemorrhagic shock (HS) or hemorrhagic shock and resuscitation (HS/R) comprising administering heparin binding epidermal growth factor (HB-EGF) to the subject. The invention is also related to methods of inhibiting deterioration of intestinal blood flow and methods of preserving and increasing intestinal blood flow by administering HB-EGF to a human subject. In addition, the methods of the invention should improve the clinical outcome of human subjects suffering from or at risk for shock, HS or HS/R.
BACKGROUND
[0003] HB-EGF was first identified in the conditioned medium of cultured human macrophages. It is synthesized as a transmembrane, biologically active precursor protein (proHB-EGF) composed of 208 amino acids, which is enzymatically cleaved by matrix metalloproteinases (MMPs) to yield a 14-20 kDa soluble growth factor (sHB-EGF). Pro-HB-EGF can form complexes with other membrane proteins including CD9 and integrin α3β1; these binding interactions function to enhance the biological activity of pro-HB-EGF. ProHB-EGF is a juxtacrine factor that can regulate the function of adjacent cells through its engagement of cell surface receptor molecules.
[0004] sHB-EGF is a potent mitogenic and chemoattractant protein for many types of cells. Similar to all members of the EGF family, HB-EGF binds to the “classic” or prototypic epidermal growth factor receptor (EGFR; ErbB-1). However, while the mitogenic function of sHB-EGF is mediated through activation of ErbB-1, its migration-inducing function involves the activation of ErbB-4 and the more recently described N-arginine dibasic convertase (NRDc, Nardilysin). This is in distinction to other EGF family members such as EGF itself, transforming growth factor (TGF)-α and amphiregulin (AR), which exert their signal-transducing effects via interaction with ErbB-1 only. In fact, the NRDc receptor is totally HB-EGF-specific. In addition, unlike most members of the EGF family, which are non-heparin binding, sHB-EGF is able to bind to cell-surface heparin-like molecules (heparan sulfate proteoglycans; HSPG), which act as low affinity, high capacity receptors for HB-EGF. The differing affinities of EGF family members for the different EGFR subtypes and for HSPG may confer different functional capabilities to these molecules in vivo. The combined interactions of HB-EGF with HSPG and ErbB-1/ErbB-4/NRDc may confer a functional advantage to this growth factor.
[0005] Although the HB-EGF gene is widely expressed, the basal level of its mRNA is relatively low in normal cells. Expression of HB-EGF is significantly increased in response to tissue damage, hypoxia and oxidative stress, and also during wound healing and regeneration. This pattern of expression is consistent with a pivotal role for HB-EGF in ischemia/reperfusion (I/R) injury, regeneration, and repair processes.
[0006] Intestinal barrier function represents a critical initial defense against noxious intraluminal substances. Although the intestine is not as essential as the vital organs in the immediate preservation of life, I/R is as lethal as extensive heart and brain ischemia. The gut has a higher critical oxygen requirement compared to the whole body and other vital organs. Accordingly, the intestinal mucosa is extremely susceptible to I/R and even short periods of ischemia can initiate local and remote tissue damage as well as systemic hemodynamic disturbances.
[0007] Reactive oxygen species (ROS), pro-inflammatory cytokines, leukocyte adhesion, and complement activation can all mediate intestinal I/R. Loss of immune and barrier functions of the gut secondary to I/R leads to significant detrimental effects on other organs such as lungs, liver, kidneys and heart, and may result in multiple organ dysfunction syndrome (MODS) and death. Exploring the potential of new therapeutic strategies to enhance the regenerative capacity and/or increase the resistance of the intestine to I/R injury would improve outcome in these patients.
[0008] The gut is highly susceptible to hypoperfusion injury due to its higher critical oxygen requirement compared to the whole body, and due to the mucosal countercurrent microcirculation. Not surprisingly, patients subjected to hypoperfusion states such as hemorrhagic shock and resuscitation (HS/R), trauma, and major surgery often develop intestinal ischemia as documented by both experimental and clinical studies.
[0009] Following the hypoperfusion effects of the shock stage, traditional methods of resuscitation often fail to adequately restore mesenteric perfusion despite stabilization of heart rate, blood pressure, and improved perfusion in some organs such as the heart and brain. To the contrary, resuscitation is characterized by progressive deterioration of mesenteric blood flow. Progressive intestinal hypoperfusion after HS/R contributes to loss of the gut mucosal barrier and to hypoxia-induced intestinal inflammation, both of which are critical to the initiation of MODS after HS/R. Accordingly, factors that protect the intestine from injury and promote early intestinal healing by restitution could significantly improve outcome after HS/R.
[0010] HB-EGF has been demonstrated to be essential for intestinal healing by restitution in intestinal epithelial cells (IEC) in vitro and in rats subjected to superior mesenteric artery occlusion (SMAO) in vivo (El-Assal & Besner Gastroenterology 129(2): 609-625. 2005). These HB-EGF-induced effects are mediated via activation of various molecular mechanisms including MEK/ERK and PI3K/Akt signaling pathways.
[0011] A few reports have demonstrated the importance of HB-EGF in promoting endothelial cell (EC) functions including angiogenesis. Exogenous HB-EGF was shown to promote rabbit corneal angiogenesis and neovascularization in mouse skin (Abramovitch et al., FEBS Lett 425(3):441-7, 1998) and recent studies have shown that HB-EGF is involved in tumor angiogenesis (Ongusaha et al. Cancer Res 64(15):5283-90, 2004), catecholamine-induced vascular trophic effects (Zhang et al., Circ Res 95(10):989-97, 2004) and angiopoietin-induced angiogenesis (Iivanainen et al., Faseb J 17(12):1609-21, 2003). HB-EGF belongs to the epidermal growth factor (EGF) family that functions via activation of the tyrosine kinase EGF receptor (EGFR). Another member of this family, EGF itself, has been shown to increase mesenteric blood flow in sheep and to induce direct relaxation of isolated rabbit mesenteric arteries via activation of EGFR. Further studies have demonstrated that the gastroprotective effects of EGF are mediated in part by its ability to increase gastric blood flow. To date, the effects of HB-EGF on mesenteric blood flow have not been elucidated.
[0012] Hemorrhagic shock (HS)-induced injuries and hemorrhagic shock and resuscitation (HS/R)-induced injuries are conditions that may result from any type of trauma or severe blood loss. Therefore, there is a continuing need to develop methods of preventing injuries due to HS or HS/R and therapeutic compositions for preventing and treating these intestinal injuries.
SUMMARY OF INVENTION
[0013] Factors that protect the intestine from HS and HS/R-induced injury and promote early intestinal healing by restitution may significantly improve the clinical outcome of human subjects suffering from HS or HS/R. Previous data has indicated that HB-EGF is essential for intestinal healing by restitution in intestinal epithelial cells. The present invention contemplates that HB-EGF may also protect the intestines from injury after HS or HS/R. The invention particularly provides for methods of treating subjects who are at risk for, or who are experiencing the early stages of HS/R by administering HB-EGF and thereby preventing, reducing or protecting the intestine from injury. The data presented herein evaluated the role of HB-EGF in preserving mesenteric blood flow and protecting the intestines from HS- or HS/R-induced injury.
[0014] The invention provides for methods of treating a human subject suffering from or at risk for HS or HS/R by administering a HB-EGF product. As demonstrated in Examples 1-6, HB-EGF protected intestinal epithelial cells and intestinal endothelial cells from HS- or HS/R-induced injury in a rat model of HS and HS/R. The invention contemplates administering HB-EGF immediately after injury or during the early stages of HS/R. The invention also contemplates administering HB-EGF to subjects at risk for HS or HS/R, such as those subjects scheduled for surgery or particularly for gastrointestinal tissue transplant, whereby administration provides an effective endogenous amount of HB-EGF at onset of HS or HS/R. Exemplary HS- or HS/R-induced injuries that may be treated, prevented or reduced by the methods of the invention are destruction of the gut mucosal barrier and deterioration of the villous microcirculatory blood flow to the intestine.
[0015] The experiments described in Example 2 used histological analysis to evaluate HS- and HS/R-induced intestinal injury. Intestinal injury was observed immediately after HS and increased as the time after resuscitation increased. In addition, intestinal injury was evaluated by measuring the number of incompetent non-healed villi per cross section on injured intestine (see Example 3). The invention provides for methods of protecting a human subject at risk for or suffering from HS- or HS/R-induced intestinal injury comprising administering a HB-EGF product to the human subject in an amount effective to protect the intestine of the human subject from injury.
[0016] Preferably, for all the methods of the invention, the HB-EGF product is a polypeptide having the amino acid sequence of SEQ ID NO: 2 or a fragment thereof that competes with HB-EGF for binding to the ErbB-1 receptor and has ErbB-1 agonist activity. A preferred HB-EGF product is human HB-EGF(74-148). In preferred embodiments, the HB-EGF product is administered in any of the methods of the invention immediately after HS or HS/R or shortly after HS or HS/R such as within about 1, about 2, about 3, about 4 or about 5 hours after resuscitation. However, the invention provides for methods of administering a HB-EGF product at any time during or after HS or HS/R has developed, such as later than about 5 hours after injury or later than about 5 hours after HS or HS/R has developed. For example, the invention contemplates administering a HB-EGF product to subjects seeking treatment several or many hours after injury or after HS has developed, or in cases where treatment is delayed for some reason. In addition, it is preferred that the HB-EGF product be administered before ischemia, hypoxia or necrotizing enterocolitis takes effect.
[0017] The experiments in Example 4 analyze in vivo villous microcirculatory blood flow in rats subjected to HS followed by variable times of reperfusion. The average microvascular villous blood flow area of HS and HS/R rats treated with a HB-EGF product was analyzed using FITC-labeled dextran. Microvascular blood flow was significantly reduced one hour after HS/R and was further reduced three hours after HS/R. The invention provides for methods of preventing or reducing HS- or HS/R-induced intestinal injury in a human subject at risk for or suffering from HS or HS/R comprising administering a HB-EGF product in an amount effective to inhibit deterioration of villous microcirculatory blood flow, e.g., to minimize the HS- or HS/R-induced decline in distribution, volume or pressure of blood in the villous microcirculation, and preferably to improve or enhance these parameters.
[0018] The villous microcirculatory blood flow analysis described in Example 4 also demonstrated that administration of a HB-EGF product to the HS and HS/R rats exhibited increased microcirculatory blood flow. The invention further provides for methods of increasing blood flow to the intestine of a human subject at risk for or suffering from HS or HS/R comprising administering HB-EGF in an amount effective to increase blood flow to the intestine. In particular, the methods of the invention will increase mesenteric blood flow.
[0019] Experiments using HB-EGF knock out (KO) mice demonstrated that HB-EGF preserved viable intestinal endothelial cells after ischemia/reperfusion (I/R) (see Example 5). In addition, the experiments in Example 6 demonstrate that HB-EGF acts as a potent vasodilator of mesenteric arterioles. The invention provides for methods of promoting angiogenesis in the intestine of a human subject at risk for or suffering from HS or HS/R comprising administering a HB-EGF product in an amount effective to protect intestinal endothelial cells from injury during or after HS or HS/R. In particular, angiogenesis is promoted by protecting intestinal endothelial cells from injury early after HS or HS/R, such as by administering HB-EGF product within about 1, about 2, about 3, about 4 or about 5 hours after HS or HS/R. Angiogenesis may also be promoted by HB-EGF-induced endothelial cell migration during or after HS or HS/R.
[0020] The invention also provides for methods of protecting microvillus architecture in a human subject at risk for or suffering from HS or HS/R comprising administering a HB-EGF product in an amount effective to preserve the intestinal microvasculature of the human subject. The invention also provides for methods in which the intestinal microvasculature is preserved due to vasodilatation induced by the HB-EGF product.
[0021] The data presented in Example 6 demonstrates that HB-EGF acts as a vasodilator. The invention provides for methods of preserving blood flow in a human subjects at risk for or suffering from intestinal injury comprising administering HB-EGF in an amount effective to promote vasodilatation of intestinal blood vessels, such as the blood vessels within the intestinal microvasculature. In particular, the invention provides for methods of preserving blood flow in a human at risk for or suffering from intestinal injury caused by HS or HS/R.
[0022] The invention also provides for methods of improving the clinical outcome of a human subject at risk for or suffering from HS or HS/R comprising administering a HB-EGF product in an amount effective to protect the intestine of the human subject from HS- or HS/R-induced intestinal injury.
[0023] The methods of the invention may be carried out in any human subject at risk for or suffering from shock, HS or HS/R. The invention contemplates treating human subjects of any age including infants, children and adults. HS may be the result of any type of injury, severe hemorrhaging, trauma, surgery, spontaneous hemorrhaging, or intestinal tissue grafting. HS causes hypotension with decreased blood flow to vital organs. Other conditions causing hypotension, although not strictly due to blood loss, may also benefit from treatment with a HB-EGF product, for example, patients with major burns, shock due to sepsis or other causes, and major myocardial infarction to name a few. In certain embodiments, the methods of the invention may be carried out in any human subject other than a subject suffering from necrotizing enterocolitis.
HB-EGF Polypeptide
[0024] The cloning of a cDNA encoding human HB-EGF (or HB-EHM) is described in Higashiyama et al., Science, 251: 936-939 (1991) and in a corresponding international patent application published under the Patent Cooperation Treaty as International Publication No. WO 92/06705 on Apr. 30, 1992. Both publications are hereby incorporated by reference herein in their entirety. In addition, uses of human HB-EGF are taught in U.S. Pat. No. 6,191,109, also incorporated by reference in its entirety.
[0025] The sequence of the protein coding portion of the cDNA is set out in SEQ ID NO: 1 herein, while the deduced amino acid sequence is set out in SEQ ID NO: 2. Mature HB-EGF is a secreted protein that is processed from a transmembrane precursor molecule (pro-HB-EGF) via extracellular cleavage. The predicted amino acid sequence of the full length HB-EGF precursor represents a 208 amino acid protein. A span of hydrophobic residues following the translation-initiating methionine is consistent with a secretion signal sequence. Two threonine residues (Thr75 and Thr85 in the precursor protein) are sites for O-glycosylation. Mature HB-EGF consists of at least 86 amino acids (which span residues 63-148 of the precursor molecule), and several microheterogeneous forms of HB-EGF, differing by truncations of 10, 11, 14 and 19 amino acids at the N-terminus have been identified. HB-EGF contains a C-terminal EGF-like domain (amino acid residues 30 to 86 of the mature protein) in which the six cysteine residues characteristic of the EGF family members are conserved and which is probably involved in receptor binding. HB-EGF has an N-terminal extension (amino acid residues 1 to 29 of the mature protein) containing a highly hydrophilic stretch of amino acids to which much of its ability to bind heparin is attributed. Besner et al., Growth Factors, 7: 289-296 (1992), which is hereby incorporated by reference herein, identifies residues 20 to 25 and 36 to 41 of the mature HB-EGF protein as involved in binding cell surface heparin sulfate and indicates that such binding mediates interaction of HB-EGF with the EGF receptor.
[0026] As used herein, “HB-EGF product” includes HB-EGF proteins comprising about amino acid 63 to about amino acid 148 of SEQ ID NO: 2 (HB-EGF(63-148)); HB-EGF proteins comprising about amino acid 73 to about amino acid 148 of SEQ ID NO: 2 (HB-EGF(73-148)); HB-EGF proteins comprising about amino acid 74 to about amino acid 148 of SEQ ID NO: 2 (HB-EGF(74-148)); HB-EGF proteins comprising about amino acid 77 to about amino acid 148 of SEQ ID NO: 2 (HB-EGF(77-148)); HB-EGF proteins comprising about amino acid 82 to about amino acid 148 of SEQ ID NO: 2 (HB-EGF(82-148)); HB-EGF proteins comprising a continuous series of amino acids of SEQ ID NO: 2 which exhibit less than 50% homology to EGF and exhibit HB-EGF biological activity, such as those described herein; fusion proteins comprising the foregoing HB-EGF proteins; and the foregoing HB-EGF proteins including conservative amino acid substitutions. In a specific embodiment, the HB-EGF product is human HB-EGF(74-148). Conservative amino acid substitutions are understood by those skilled in the art. The HB-EGF products may be isolated from natural sources known in the art (e.g., the U-937 cell line (ATCC CRL 1593)), chemically synthesized, or produced by recombinant techniques such as disclosed in WO92/06705, supra, the disclosure of which is hereby incorporated by reference. In order to obtain HB-EGF products of the invention, HB-EGF precursor proteins may be proteolytically processed in situ. The HB-EGF products may be post-translationally modified depending on the cell chosen as a source for the products.
[0027] The HB-EGF products of the invention are contemplated to exhibit one or more biological activities of HB-EGF, such as those described in the experimental data provided herein or any other HB-EGF biological activity known in the art. One such biological activity is that HB-EGF products compete with HB-EGF for binding to the ErbB-1 receptor and has ErbB-1 agonist activity. In addition, the HB-EGF products of the invention may exhibit one or more of the following biological activities: cellular mitogenicity, cellular chemoattractant, endothelial cell migration, acts as a pro-survival factor (protects against apoptosis), decrease inducible nitric oxide synthase (iNOS) and nitric oxide (NO) production in epithelial cells, decrease nuclear factor-κB (NF-κB) activation, increase eNOS (endothelial nitric oxide synthase) and NO production in endothelial cells, stimulate angiogenesis and promote vasodilatation.
[0028] The present invention provides for the HB-EGF products encoded by the nucleic acid sequence of SEQ ID NO: 1 or fragments thereof including nucleic acid sequences that hybridize under stringent conditions to the complement of the nucleotides sequence of SEQ ID NO: 1, a polynucleotide which is an allelic variant of any SEQ ID NO: 1; or a polynucleotide which encodes a species homolog of SEQ ID NO: 2.
[0029] The HB-EGF products may also be encoded by nucleotide sequences that are substantially equivalent to the polynucleotides recited above. Polynucleotides according to the invention can have at least, e.g., 65%, 70%, 75%, 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, or 89%, more typically at least 90%, 91%, 92%, 93%, or 94% and even more typically at least 95%, 96%, 97%, 98% or 99% sequence identity to the polynucleotides recited above. Preferred computer program methods to determine identity and similarity between two sequences include, but are not limited to, the GCG program package, including GAP (Devereux et al., Nucl. Acid. Res., 12: 387, 1984; Genetics Computer Group, University of Wisconsin, Madison, Wis.), BLASTP, BLASTN, and FASTA (Altschul et al., J. Mol. Biol., 215: 403-410, 1990). The BLASTX program is publicly available from the National Center for Biotechnology Information (NCBI) and other sources (BLAST Manual, Altschul et al. NCB/NLM/NIH Bethesda, Md. 20894; Altschul et al., supra). The well known Smith Waterman algorithm may also be used to determine identity.
[0030] Included within the scope of the nucleic acid sequences of the invention are nucleic acid sequence fragments that hybridize under stringent conditions to SEQ ID NO: 1, or compliments thereof, which fragment is greater than about 5 nucleotides, preferably 7 nucleotides, more preferably greater than 9 nucleotides and most preferably greater than 17 nucleotides. Fragments of, e.g., 15, 17, or 20 nucleotides or more that are selective for (i.e., specifically hybridize to any one of the polynucleotides of the invention) are contemplated.
[0031] The term “stringent” is used to refer to conditions that are commonly understood in the art as stringent. Hybridization stringency is principally determined by temperature, ionic strength, and the concentration of denaturing agents such as formamide. Examples of stringent conditions for hybridization and washing are 0.015 M sodium chloride, 0.0015 M sodium citrate at 65-68oC or 0.015 M sodium chloride, 0.0015M sodium citrate, and 50% formamide at 42oC. See Sambrook et al., Molecular Cloning: A Laboratory Manual, 2nd Ed., Cold Spring Harbor Laboratory, (Cold Spring Harbor, N.Y. 1989). More stringent conditions (such as higher temperature, lower ionic strength, higher formamide, or other denaturing agent) may also be used, however, the rate of hybridization will be affected. In instances wherein hybridization of deoxyoligonucleotides is concerned, additional exemplary stringent hybridization conditions include washing in 6×SSC 0.05% sodium pyrophosphate at 37° C. (for 14-base oligos), 48° C. (for 17-base oligos), 55° C. (for 20-base oligos), and 60° C. (for 23-base oligos).
[0032] Other agents may be included in the hybridization and washing buffers for the purpose of reducing non-specific and/or background hybridization. Examples are 0.1% bovine serum albumin, 0.1% polyvinyl-pyrrolidone, 0.1% sodium pyrophosphate, 0.1% sodium dodecylsulfate, NaDodSO4, (SDS), ficoll, Denhardt's solution, sonicated salmon sperm DNA (or other non-complementary DNA), and dextran sulfate, although other suitable agents can also be used. The concentration and types of these additives can be changed without substantially affecting the stringency of the hybridization conditions. Hybridization experiments are usually carried out at pH 6.8-7.4, however, at typical ionic strength conditions, the rate of hybridization is nearly independent of pH. See Anderson et al., Nucleic Acid Hybridisation: A Practical Approach, Ch. 4, IRL Press Limited (Oxford, England). Hybridization conditions can be adjusted by one skilled in the art in order to accommodate these variables and allow DNAs of different sequence relatedness to form hybrids.
[0033] The HB-EGF products of the invention include, but are not limited to, a polypeptide comprising: the amino acid sequences encoded by the nucleotide sequence of SEQ ID NO: 1, or the corresponding full length or mature protein. Polypeptides of the invention also include polypeptides preferably with HB-EGF biological activity described herein that are encoded by: (a) an open reading frame contained within the nucleotide sequences set forth as SEQ ID NO: 1, preferably the open reading frames therein or (b) polynucleotides that hybridize to the complement of the polynucleotides of (a) under stringent hybridization conditions.
[0034] The HB-EGF products of the invention also include biologically active variants of the amino acid of SEQ ID NO: 2; and “substantial equivalents” thereof with at least, e.g., about 65%, about 70%, about 75%, about 80%, about 85%, 86%, 87%, 88%, 89%, at least about 90%, 91%, 92%, 93%, 94%, typically at least about 95%, 96%, 97%, more typically at least about 98%, or most typically at least about 99% amino acid identity) that retain HB-EGF biological activity. Polypeptides encoded by allelic variants may have a similar, increased, or decreased activity compared to polypeptides having the amino acid sequence of SEQ ID NO: 2.
[0035] The HB-EGF products of the invention include HB-EGF polypeptides with one or more conservative amino acid substitutions that do not affect the biological activity of the polypeptide. Alternatively, the HB-EGF polypeptides of the invention are contemplated to have conservative amino acids substitutions which may or may not alter biological activity. The term “conservative amino acid substitution” refers to a substitution of a native amino acid residue with a nonnative residue, including naturally occurring and nonnaturally occurring amino acids, such that there is little or no effect on the polarity or charge of the amino acid residue at that position. For example, a conservative substitution results from the replacement of a non-polar residue in a polypeptide with any other non-polar residue. Further, any native residue in the polypeptide may also be substituted with alanine, according to the methods of “alanine scanning mutagenesis”. Naturally occurring amino acids are characterized based on their side chains as follows: basic: arginine, lysine, histidine; acidic: glutamic acid, aspartic acid; uncharged polar: glutamine, asparagine, serine, threonine, tyrosine; and non-polar: phenylalanine, tryptophan, cysteine, glycine, alanine, valine, proline, methionine, leucine, norleucine, isoleucine.
Hemorrhagic Shock
[0036] Shock is a state of inadequate perfusion, which does not sustain the physiologic needs of organ tissues. Hemorrhagic shock (HS) refers to shock that is caused by blood loss that exceeds the ability of the body to compensate and to provide adequate tissue perfusion and oxygenation. HS is frequently is caused by trauma, but also may be caused by spontaneous hemorrhage (e.g., GI bleeding, childbirth), surgery, and other causes. Frequently, an acute bleeding episode will cause HS, but HS may also occur in chronic conditions with subacute blood loss.
[0037] Untreated HS can lead to death. Without intervention, a classic trimodal distribution is seen in severe HS. An initial peak of mortality occurs within minutes of hemorrhage due to immediate exsanguination. Another peak occurs after 1 to several hours due to progressive decompensation. A third peak occurs days to weeks later due to sepsis and organ failure. Therefore, the methods of the invention preferably are carried out during the early stages of HS such as after or during the initial peak, or before or during the second peak (1 to several hours after the initial hemorrhage).
[0038] A person in shock has extremely low blood pressure. Depending on the specific cause and type of shock, symptoms will include one or more of the following: anxiety, agitation, confusion, pale, cool and clammy skin, low or no urine production, bluish lips and fingernails, dizziness, light-headedness, faintness, profuse sweating, rapid but weak pulse, shallow breathing, chest pain and unconsciousness.
[0039] Resuscitation during or after HS/R is known to have deletorious effects on the blood vessels of the patient. For example, HS/R is characterized by progressive deterioration of mesenteric blood flow. In addition, progressive intestinal hypoperfusion after HS/R contributes to loss of the gut mucosal barrier and to hypoxia-induced intestinal inflammation, both of which are critical to the initiation of MODS after HS/R.
The Role of HB-EGF in Intestinal Cytoprotection
[0040] Induction and activation of the EGF receptor have been demonstrated in different tissues, including the intestines, during hypoxia and after ischemia. (Ellis et al., Biochem. J. 354:99-106, 2001; Lin et al., J Lab Clin Med; 125:724-33, 1995; Nishi et al., Cancer Res 62:827-34, 2002; Sondeen et al., J Lab Clin Med 134:641-8, 1999; Yano et al., Nephron 81:230-3, 1999). Previous studies have shown that HB-EGF mRNA and protein are induced after exposure of intestinal epithelial cells to anoxia/reoxygenation (A/R) in vitro, and after intestinal I/R injury in vivo. (Xia et al., J Invest Surg 16:57-63, 2003). Hypoxia and I/R have been found to induce HB-EGF transcription and protein synthesis in different tissues including the brain and kidney. (Homma et al., J Clin Invest 96:1018-25, 1995; Jin et al., J Neurosci 22:5365-73, 2002; Kawahara et al., J Cereb Blood Flow Metab 19:307-20, 1999; Sakai et al., J. Clin. Invest.; 99:2128-2138, 1997). During the early phases of hypoxia and oxidative stress, activation of EGFR and shedding of proHB-EGF occur, leading to immediate availability of soluble HB-EGF protein for targeting via autocrine or paracrine pathways. HB-EGF shedding is followed by the induction of transcription and de novo synthesis of HB-EGF (El-Assal et al., Semin Pediatr Surg 13:2-10, 2004).
[0041] Intestinal epithelium undergoes a dynamic and continuous process of renewal and replacement with a turnover time of 3-6 days. (Potten et al., Am J Physiol 273:G253-7, 1997). Depending more on the depth of injury rather than the total surface area affected, the process of healing starts as early as a few minutes after injury (Ikeda et al., Dig Dis Sci 2002; 47:590-601, 2002). The most important priority during intestinal regeneration is reconstitution of epithelial cell continuity, allowing restoration of bather function and prevention of systemic toxic complications. This is achieved by rapid epithelial cell migration from the wound edge, a process known as “restitution” (Ikeda et al., Dig Dis Sci 47:590-601, 2002; McCormack et al., Am J Physiol; 263:G426-35, 1992; Moore et al. Am J Physiol 257:G274-83, 1989; Moore et al. Gastroenterology 102:119-30, 1992). Early migration of goblet cells, which are more resistant to ischemia-induced cell death than enterocytes, serves as a source of both cell lining and mucous secretion, thus promoting rapid recovery of intestinal barrier function (Ikeda et al., Dig Dis Sci 47:590-601, 2002). Complete intestinal repair is achieved by proliferation and differentiation of crypt epithelium, which does not occur as early as restitution. Following administration of HB-EGF to rats exposed to intestinal I/R, a significant improvement in intestinal healing characterized by reduced mucosal damage was observed (Pillai et al., J Surg Res 87:225-31, 1999). The early phase of intestinal healing HB-EGF was shown to induce intestinal restitution (El-Assal et al., Gastroenterology 129:609-25, 2005) whereas in the later phase of healing HB-EGF promotes crypt cell proliferation (Xia et al., J Pediatr Surg 37:1081-7; 2002). In addition, the effects of HB-EGF in inducing restitution are mediated by both the PI3-kinase and MAPK intracellular signaling pathways (El-Assal et al. Gastroenterology 129:609-25, 2005). HB-EGF administration leads to preservation of gut barrier function and intestinal permeability after intestinal I/R (El-Assal et al. Gastroenterology 129:609-25, 2005), with resultant decrease in bacterial translocation (Xia et al., J Pediatr Surg 37:1081-7; 2002). It is important to note that the protective effects of HB-EGF administration are seen even when the growth factor is administered during or after the ischemic interval has already occurred (Martin et al., J Pediatr Surg. 40:1741-7, 2005). Thus, prophylactic administration of HB-EGF prior to ischemia is not required. Most importantly, HB-EGF improves survival in rats exposed to intestinal I/R injury (Pillai et al., J Surg Res 87:225-31, 1999).
[0042] Additional studies demonstrated that treatment with HB-EGF reduced the generation of ROS in rats exposed to intestinal I/R in vivo and in leukocytes exposed to ROS-inducing stimuli in vitro (Kuhn et al., Antioxid Redox Signal 4:639-46, 2002). HB-EGF also preserved intestinal epithelial cell ATP levels in cells exposed to hypoxia (Pillai et al., J. Pediatr. Surg. 33:973-979, 1998). HB-EGF is known to downregulate expression of adhesion molecules including P- and E-selectin and intercellular adhesion molecule-1 (ICAM-1)/vascular cell adhesion molecule-1 (VCAM-1) after intestinal I/R (Xia et al., J Pediatr Surg 38:434-9. 2003). Downregulation of adhesion molecules was followed by reduced infiltration of leukocytes, which are critical mediators of I/R (Xia et al., J Pediatr Surg 38:434-9. 2003).
[0043] Exposure of intestinal epithelium to I/R results in cell death, with apoptosis rather than necrosis as the major mechanism of cell death. One of the unique functions of HB-EGF is its ability to protect against apoptotic cell death. sHB-EGF is known to protect enterocytes from hypoxia-induced intestinal necrosis (Pillai et al., J. Pediatr. Surg. 33:973-979, 1998) and from pro-inflammatory cytokine-induced apoptosis (Michalsky et al., J Pediatr Surg 36:1130-5. 2001) in vitro. HB-EGF is also known to act as a pro-survival factor in cells exposed to various forms of stress including mechanical stress, serum starvation and exposure to cytotoxic agents. Recent studies have demonstrated that HB-EGF decreases intestinal epithelial cell apoptosis in vivo in a rat model of necrotizing enterocolitis (Feng et al., J Pediatr Surg 2006 (in press).
[0044] Nitric oxide (NO) is another mediator of I/R-induced apoptosis and intestinal mucosal damage. Despite the protective effect of constitutive NO, there is ample evidence that high levels of NO induce apoptosis and mediate tissue damage in different cell types including intestinal epithelial cells during I/R. iNOS (inducible nitric oxide synthase) inhibitors led to attenuated NO production and decreased hypoxia-induced intestinal apoptosis with preservation of gut barrier function in rats with endotoxemia. Furthermore, iNOS knock-out mice are more resistant to intestinal PR-induced mucosal injury. Collectively, these studies clearly indicate that reduction of iNOS can decrease I/R-induced intestinal damage. HB-EGF downregulates cytokine-induced iNOS and NO production in intestinal epithelial cells in vitro, and I/R-induced intestinal iNOS expression and serum NO levels in vivo. HB-EGF has been shown to decrease iNOS and NO production in intestinal epithelial cells that is dependent upon its ability to decrease nuclear factor-κB (NF-κB) activation in a PI3-kinase dependent fashion. Reduction of PR-induced overproduction of NO in IEC represents an additional cytoprotective mechanism of HB-EGF.
[0045] HB-EGF is a hypoxia- and stress-inducible gene that is involved in reduction of PR-induced tissue damage. It promotes structural recovery after I/R by enhancing cell proliferation and by inducing migration of healthy epithelial cells from the edge of damaged tissues. In addition to promoting healing based on its positive trophic effects, HB-EGF also protects the intestine by decreasing leukocyte infiltration and production of injurious mediators after injury, thus protecting epithelial cells from apoptosis and necrosis. It is likely that reducing I/R-induced IEC death will ameliorate intestinal damage and reduce systemic complications.
HB-EGF and Angiogenesis
[0046] Angiogenesis, the formation of new blood vessels, is an essential part of both normal developmental processes and many pathologic processes, ranging from organ growth in the embryo to repair of wounded tissue in the adult. In response to a stimulus from an angiogenic growth factor, endothelial cells migrate into the interstitial space by first degrading the underlying basement membrane. Behind the front of migrating cells, other endothelial cells continuously proliferate to provide the necessary number of cells needed to generate the new vessel (neoangiogenesis). Angiogenesis is a critical event in wound healing, and angiogenic growth factors are key to the initiation of angiogenesis and maintenance of the vascular network.
[0047] Vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) are potent angiogenic growth factors. However, there is growing evidence that HB-EGF may also be a potent stimulator of angiogenesis (Ushiro et al., Jpn. J. Cancer Res. 87:68-77, 1996; Abramovitch et al., FEBS Lett. 425:441-447, 1998). HB-EGF is expressed in endothelial cells and is also induced by VEGF. HB-EGF was found to enhance neurogenesis and angiogenesis after focal cerebral ischemia in rats (Sugiura et al., Stroke 36:859-64, 2005). The data provided in Examples 5 and 6 demonstrates that HB-EGF protects EC and preserves microvascular blood flow after intestinal I/R injury.
Pharmaceutical Compositions
[0048] The administration of HB-EGF products is preferably accomplished with a pharmaceutical composition comprising an HB-EGF product and a pharmaceutically acceptable carrier. The carrier may be in a wide variety of forms depending on the route of administration. Suitable liquid carriers include saline, PBS, lactated Ringer solution, human plasma, human albumin solution, 5% dextrose and mixtures thereof. The route of administration may be oral, rectal, parenteral, or through a nasogastric tube. Examples of parenteral routes of administration are intravenous, intra-arterial, intraperitoneal, intraluminally, intramuscular, intragastrically or subcutaneous injection or infusion. The presently preferred route of administration is the oral route as the present invention contemplates that the acid stability of HB-EGF is a unique factor as compared to, for example, EGF. The HB-EGF pharmaceutical composition may also include other ingredients to aid solubility, or for buffering or preservation purposes. Pharmaceutical compositions containing HB-EGF products comprise HB-EGF at a concentration of about 0.05 to 10 mg/ml and preferably at a concentration of 1 mg/ml in saline. Suitable doses are in the range from 0.5-1000 μg/kg, e.g., 1-10 μg/kg or 600-800 μg/kg. A preferred dose is 600 μg/kg administered intravenously once a day. Additional preferred doses may be administered once, twice, three, four, five or six times a day either enterally or intravenously. The HB-EGF may be administered as a bolus, either once at the onset of therapy or at various time points during the course of therapy, such as every four hours, or may be infused for instance at the rate of about 0.01 μg/kg/h to about 5 μg/kg/h during the course of therapy until the patient shows signs of clinical improvement. Addition of other bioactive compounds [e.g., antibiotics, free radical scavenging or conversion materials (e.g., vitamin E, beta-carotene, BHT, ascorbic acid, and superoxide dimutase), fibrolynic agents (e.g., plasminogen activators), and slow-release polymers] to the HB-EGF compounds or separate administration of the other bioactive compounds is also contemplated.
DETAILED DESCRIPTION
[0049] The following examples illustrate the invention wherein Example 1 describes a rat model of hemorrhagic shock and resuscitation, Example 2 demonstrates that HB-EGF decreases intestinal histologic damage after HS/R, Example 3 demonstrates that HB-EGF preserves the structural intestinal barrier after HS/R, Example 4 demonstrates that HB-EGF improves mesenteric blood flow after HS/R, Example 5 demonstrates that HB-EGF preserves EC after intestinal I/R injury and Example 6 demonstrates that HB-EGF is a potent vasodilator of the intestinal microvasculature.
Example 1
Rat Model of Hemorrhagic Shock and Resuscitation
[0050] All procedures were approved by the Institutional Animal Care and Use Committee of the Children's Research Institute. Adult male pathogen-free Sprague-Dawley rats weighing 250-300 g were used after acclimatization for 72 hours. Animals were fasted overnight with access to water only prior to surgery. Under inhalation anesthesia using 2% isoflurane, the right carotid artery was canulated using a PE-50 catheter connected to a three way stopcock for monitoring of mean arterial blood pressure (MAP) and heart rate as well as blood withdrawal. Cannulae and syringes were flushed with heparinized saline (1000 U/ml). Shock was produced by gradual blood withdrawal over 15 minutes to achieve a mean arterial blood pressure of 45 mmHg. MAP was maintained at that level for 90 minutes, with continuous monitoring of blood pressure, and blood withdrawal or fluid infusion as needed. Resuscitation was then achieved by gradual reperfusion of the withdrawn blood in addition to lactated Ringer's solution to achieve a MAP of ≧85% of the pre-shock level.
[0051] Rats were divided into three groups: 1) HS/R+HB-EGF group (HS/R+HB-EGF), which received a single bolus intra-arterial injection of rHB-EGF (600 μg/kg) at the onset of resuscitation, 2) HS/R group, which received an identical intra-arterial injection of vehicle (0.1% bovine serum albumin in phosphate buffer saline) only, and 3) control group, subjected to identical procedures without blood withdrawal. Throughout the procedure the animal's body temperature was maintained at 37° C. All animals recovered completely from the initial operative procedure. Three rats were used per group, with each experiment performed in duplicate. For analysis, animals were euthanized under anesthesia. All experiments utilized human rHB-EGF corresponding to amino acids 74-148 of the mature HB-EGF protein that was produced by recombinant DNA technology and purified as previously described in Davis et al. ( Protein Expr. Purif., 8(1):57-67, 1996)
Example 2
HB-EGF Decreases Intestinal Histologic Damage after HS/R
[0052] There were no significant differences in MAP among different animals before HS or after resuscitation. To measure the histology injury score, the distal 5 cm of ileum rats suffering from HS was harvested immediately upon sacrifice and specimens were paraffin embedded. Tissue sections were deparaffinized, rehydrated, and stained with hematoxylin and eosin (H&E). Histological scoring of the depth of tissue injury was performed according to Chiu et al. ( Arch. Surg. 101(4):478-83, 1970), with modifications as follows: score 0, no damage; score 1, subepithelial space at the villous tip; score 2, loss of mucosal lining of the villous tip; score 3, loss of less than half of the villous structure; score 4, loss of more than half of the villous structure; and score 5, transmural necrosis. Sections were evaluated blindly without prior knowledge of animal background.
[0053] HS-induced intestinal histological injury was compatible to that previously observed after SMAO. Immediately after HS, the average histological injury score was 1.6±0.41. In HS/R rats, this increased to 2.5±0.5 one hour after resuscitation, and increased further to 3.08±0.51 three hours after resuscitation, the latter being significantly higher than the depth of injury immediately after HS (p<0.05), indicating that HS-induced intestinal injury progressively increases after resuscitation.
[0054] In HS/R+HB-EGF rats, the average depth of intestinal injury was 1.8±0.71 one hour after resuscitation and 2.0±0.5 3 hours after resuscitation. In these rats, the post-resuscitation intestinal injury scores were not significantly different from the injury score at the end of HS. However, the injury score in HS/R+HB-EGF rats was significantly lower than that in HS/R rats three hours after resuscitation (p<0.05), indicating that HB-EGF treatment protected the intestine from resuscitation-induced intestinal injury.
Example 3
HB-EGF Preserves the Structural Intestinal Barrier after HS/R
[0055] Quantification of incompetent villi was used to evaluate the structural intestinal barrier as previously described. (El-Assal et al. Gastroenterology 129(2):609-25, 2005) An incompetent villous was identified as a villous with an incomplete mucosal lining, regardless of the depth of injury. Any epithelial gap was considered as a potential port of bacterial or macromolecular translocation into the submucosal space, and hence was considered a breach in the intestinal barrier. The number of incompetent villi reflects both the functional integrity of the intestinal barrier as well as early healing by restitution. The degree of in vivo restitution was evaluated using the criteria set out in El-Assal et al. These criteria are applied to well-aligned villi in PAS-stained sections and include: 1) histologic features indicative of prior loss of mucosa resulting in subsequent villous contraction, with short, blunted, or concave villous tips compared to non-damaged or less injured villi in the same histologic section; 2) restoration of the mucosal surface of injured villi with a single layer of flat, squamous enterocytes resulting from migration and flattening during restitution; and/or 3) restoration of mucosal continuity with a single cell layer containing four or more goblet cells in continuity, without intervening enterocytes. The average numbers of incompetent villi per cross section were quantified as an indicator of intestinal restitution.
[0056] At the end of HS, the average number of incompetent non-healed villi per cross section was 11.3±4.5. The number of incompetent villi in HS/R rats increased to 39.9±17 one hour after resuscitation and to 31.7±6.4 three hours after resuscitation, the latter being significantly higher than that at the end of HS (p<0.05). In HS/R+HB-EGF rats, the number of incompetent villi was 9.9±4.4 one hour after resuscitation, and 9.08±4.3 three hours after resuscitation, both significantly lower than that in HS/R rats. This indicates that HB-EGF protects against resuscitation-induced destruction of the gut mucosal barrier.
Example 4
HB-EGF Improves Mesenteric Blood Flow after HS/R
[0057] Villous microcirculatory blood flow was evaluated in vivo according to the method of Stappenbeck et al. ( Proc. Natl. Acad. Sci. USA 99(24):15451-5, 2002) with some modifications. Rats were subjected to HS for 90 minutes followed by variable periods of reperfusion. High molecular weight (FD2000) fluorescein isothiocyanate-labeled (FITC) dextran (500 μl of a 10 mg/ml solution, Sigma, St. Louis, Mo.) was injected into the carotid artery 5 minutes prior to sacrifice. An 8 cm segment of distal small bowel was excised, perfused with fixation solution containing 0.5% paraformaldehyde, 15% picric acid, and 0.1 M sodium phosphate buffer (pH 7.0), and shaken gently at 4° C. for 12 hours in fixation solution. Specimens were rinsed in ice-cold PBS (three washes, 5 minutes each), followed by a 3 hour incubation in 10% sucrose/PBS (4° C.) and an overnight incubation in 20% sucrose/10% glycerol/PBS (4° C.).
[0058] Intestinal segments were frozen in OCT compound and 60 μm-thick sections were cut across the cephalocaudal axis. Sections were air-dried for 2 hours at room temperature (RT) in the dark, followed by rehydration in ice-cold PBS (1 minute) and overnight incubation at 4° C. in 3% deoxycholic acid (Sigma). Sections were rinsed twice in water (5 minutes each at room temperature), and once in PBS (5 minutes at room temperature) to remove residual deoxycholic acid. Intestinal epithelial cells (IEC) were stained by incubating sections in a 1:1000 solution of Syto61 (Molecular Probes, Carlsbad, Calif.) for 1 hour at room temperature, followed by three PBS washes (5 minutes each at room temperature). Sections were mounted in 50% glycerol/PBS and stored at 4° C. Cryosections were viewed with an LSM 510 confocal microscope (Zeiss, Thornwood, N.Y.) and scanned at 5 μm-thick intervals. Scans were projected in three dimensions by taking 8-10 serial images, aligning them at 7-10° intervals, and compiling/rotating them about the y axis using LSM 510 software (Zeiss).
[0059] The extent of microvascular perfused area was quantified using MetaMorph computer software. Scanned images were processed to separate the green channel representing the perfused area and the red channel representing epithelial cell staining. The extent of green staining per section was indicative of the perfused area %. Three rats were used per group, with each experiment performed in duplicate. At least 5 sections were evaluated per animal.
[0060] The average microvascular villous blood flow area % was 3.9±0.35% prior to HS (basal flow). Microvascular blood flow was significantly reduced to 2.6±0.46% in HS/R rats one hour after resuscitation compared to basal pre-HS levels (p<0.05) and to 2.9±0.63% three hours after resuscitation. This indicated that HS/R resulted in significant deterioration in microvascular flow with vasoconstriction of the villous vasculature, consistent with previous studies (Zakaria et al. Am J Surg 186(5):443-8, 2003; Fruchterman et al. Shock 10(6):417-22, 1998).
[0061] Treatment with HB-EGF not only prevented HS/R-induced deterioration of villous microcirculatory blood flow, but actually resulted in increased flow compared to basal levels. In HS/R+HB-EGF rats, the average microvascular villous blood flow area % was 4.5±0.43% 1 hour after resuscitation, which was significantly higher than that in HS/R rats at this time point (p<0.05). Three hours after resuscitation the villous microcirculatory perfused area % in HS/R+HB-EGF rats increased to 8.04±1.5%, which was significantly higher than that in HS/R rats at this time point, and significantly higher than basal pre-HS levels (p<0.05).
Example 5
HB-EGF Preserves Endothelial Cells After Intestinal I/R Injury
[0062] An additional possible mechanism by which HB-EGF might promote angiogenesis after I/R is via protection of EC from injury after the initial insult. To investigate the role of HB-EGF in preservation of viable EC, intestine from HB-EGF knock-out (KO) and wild type (WT) mice was examined by IHC using anti-von Willebrand factor (VWF) antibodies to stain EC (Jackson et al. Embo J 22: 2704-2716, 2003). After exposure to I/R injury, HB-EGF KO mice have significantly decreased EC staining compared to WT mice. Similar results were obtained using anti-CD34 and anti-αSMA. Thus, HB-EGF protects EC from injury after intestinal I/R. This may leave a population of viable EC available for prompt initiation of angiogenesis after I/R.
Example 6
HB-EGF is a Potent Vasodilator of the Intestinal Microvasculature
[0063] Preservation of blood flow after intestinal injury is a major determinant of subsequent tissue viability, and is dependent upon flow through the main resistance vessels, the terminal mesenteric arterioles. The effect of HB-EGF on the pressure and flow characteristics of freshly isolated individual porcine terminal mesenteric arterioles was examined (˜200 μm). These studies demonstrate that HB-EGF acts as a potent vasodilator of mesenteric arterioles. Thus, HB-EGF protects EC and preserves the patency of the microvasculature after I/R injury, and acts as a vasodilator of the intestinal circulation as well. | The invention is related to methods of protecting, preventing and reducing intestinal injury in a human subject suffering from or at risk for shock, hemorrhagic shock or hemorrhagic shock and resuscitation (HS/R) comprising administering heparin binding epidermal growth factor (HB-EGF). The invention is also related to methods of inhibiting deterioration of intestinal blood flow and methods of preserving and increasing intestinal blood flow by administering HB-EGF to a human subject. In addition, the methods of the invention should improve the clinical outcome of human subject suffering from or at risk for shock, hemorrhagic shock or hemorrhagic shock and resuscitation. | 0 |
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