Patents Examined by Thomas A. Robinson
  • Patent number: 4390984
    Abstract: In a data transmission system with such a construction that a plurality of terminal units are connected to a first and a second loop transmission line for transmitting messages in a first direction and in a second direction which is opposite to said first direction, respectively, through a pair of transmission control units (the one unit being connected to said first loop transmission line with the other unit being connected to said second loop transmission line), each transmission control unit sends a check message sequentially in order to check the state of a minor loop which connects two adjacent pairs of transmission control units. This check message has a data field, in which an initial value is set at the sending time. The value of this data field is incremented by one in each transmission control unit through which the message passes to make a round through the minor loop.
    Type: Grant
    Filed: September 9, 1981
    Date of Patent: June 28, 1983
    Assignee: Hitachi, Ltd.
    Inventors: Kazumasa Sugiura, Kinji Mori, Hirokazu Ihara, Yoshinori Kawai
  • Patent number: 4390982
    Abstract: A small capacity digital PBX-key system which uses a single processor to control the system. Since only a single processor is employed, the system is interrupt controlled. In the system, there is a codec per line, the codecs each having sufficient programmability to eliminate the need for time slot interchangers. To provide as many as 64 (or more) channels usable for speech, tones and conferencing, two (or more) parallel, 32 channel busses are used as the group bus. The stations and trunks (ports) of the system have access to both busses through the codecs. Information is routed to one or another bus through the transmission of bus control bits from the processor.
    Type: Grant
    Filed: January 14, 1981
    Date of Patent: June 28, 1983
    Assignee: International Telephone and Telegraph Corporation
    Inventors: William H. Williams, Michael G. Burke
  • Patent number: 4389721
    Abstract: A loop controller transmits data to and receives data from a plurality of I/O ports on a TDM serial loop by generating a plurality of frames which include a frame control field followed by a plurality of dedicated time slot fields. Each time slot field includes an inbound data control bit or bits followed by a data field followed by an outbound data control bit or bits. The I/O port inputs and outputs data in its dedicated data field as dictated by the respective data control bit. The loop controller and I/O ports monitor the data control bit to request data, indicate insertion of data, indicate receipt of the data and acknowledge the receipt indication to achieve a complete handshake. During an initialization frame, the I/O ports set themselves into primary and secondary data modes based on sensing a prior I/O port with the same dedicated time slot.
    Type: Grant
    Filed: June 30, 1981
    Date of Patent: June 21, 1983
    Assignee: Harris Corporation
    Inventors: William R. Young, Stanley R. Zepp
  • Patent number: 4389646
    Abstract: A displacement converting circuit arrangement comprising first and second capacitors in the form of a paired structure, at least one of the capacitors having a capacitance which is varied in response to a mechanical displacement. Means are provided for deriving first and second currents respectively proportional to the capacitances of the first and second capacitors, means for maintaining at least one of the DC currents corresponding to at least one capacitor having a variable capacitance at a fixed amount, and means for producing an output current corresponding to the difference between the DC currents, so that the output current indicates the amount of the mechanical displacement. Operation stability is improved by the simplified circuit arrangement, with consequent reduction in error and circuit failure. The movable electrode for varying the capacitance can withstand a heavy load.
    Type: Grant
    Filed: March 31, 1981
    Date of Patent: June 21, 1983
    Assignee: Fuji Electric Co. Ltd.
    Inventor: Keiichiro Tago
  • Patent number: 4388489
    Abstract: A video conversational data communication network (30) in which subscribers (34, 35) may conduct conversational video textual data communications with one or more keystations (70, 602, 98) the network (30). Each keystation (70, 602, 98) is associated with a keystation terminal controller interface (68, 96, 600) which is in turn connected to a message switching node (32) for routing calls throughout the network (30). The keystation controller interface (68, 96, 600) locally stores (304, 306) video conversational textual data for its associated keystations (70, 82, 84, 98, 100, 602) and enables two different designated keystations to conduct two different video conversations with a common keystation in a split screen display (76). The split screen display (76) may also be used to display retrievable data from a data base (50, 52) for simultaneous display (76) along with a video conversation.
    Type: Grant
    Filed: January 30, 1981
    Date of Patent: June 14, 1983
    Assignee: Reuters Limited
    Inventors: Jack G. Wigan, David G. Ure, John M. Richards
  • Patent number: 4388718
    Abstract: A digital telecommunication system has a plurality of 64 kbit/s channels subdivided into respective 56 kbit/s primary channels and 8 kbit/s auxiliary channels. Continuously from subscriber-to-subscriber, the 56 kbit/s primary channels serve respectively alternately for the transmission of pulse code modulated or delta modulated speech signals and/or rapid fixed image transmission or rapid data transmission, whereas the 8 kbit/s auxiliary channels are only available for the transmission or exchange-oriented signaling characters, slow fixed image transmission, slow data transmission from subscriber-to-subscriber, as well as for transmission of subscriber-to-subscriber control information and/or remote control and similar special service information.
    Type: Grant
    Filed: January 26, 1981
    Date of Patent: June 14, 1983
    Assignee: Siemens Aktiengesellschaft
    Inventors: Peter Gerke, Joachim Petersen
  • Patent number: 4388501
    Abstract: An audio-visual line test termination device for providing a characteristic signature to the telephone central office and a visual and an audible signal to the customer when a continuity test is made on a subscriber line having a pair of electrically conductive paths includes a miniature audio indicator, a light source and a minimum of associated electrical components to indicate to the central office test operator and the customer that the telephone subscriber line is in operating order. The instant invention may be utilized together with a housing that may be permanently installed across the subscriber line.
    Type: Grant
    Filed: May 11, 1981
    Date of Patent: June 14, 1983
    Assignee: TII Industries Inc.
    Inventor: Omprakash G. Ahuja
  • Patent number: 4387367
    Abstract: A matrixed, optical keyboard comprising structure 10 defining an array of touch areas 14 arranged in rows 16 and columns 17, and paired light sources and light sensors 20, 22 disposed at opposite ends of each row and each column and positioned to define a path of light. Light refocussing elements 24 are disposed contiguously about and define the touch areas and extend into the light path thereby refocussing the light beam prior to traversing each touch area and prior to impinging on the associated light sensor. In one embodiment, the keyboard and light refocussing elements are integrally molded and form a unitary structure. In another embodiment, the keyboard is formed with structure for maintaining an indicia card 44 behind and in alignment with the touch areas so that indicia area 44a are visible through the touch areas 14'.
    Type: Grant
    Filed: June 19, 1981
    Date of Patent: June 7, 1983
    Inventor: Charles R. Fisher
  • Patent number: 4387278
    Abstract: A telephony network with a digital central office and a one or more remotely located digital satellite units. Each digital satellite unit connects to a number of remote subscriber lines and monitors these lines to establish communications through interconnecting spans and a digital satellite interface at the digital central office. The digital satellite interface includes a programmed controller that communicates with the remote digital satellite units connected to it, with call processing equipment in the digital central office and with maintenance processing equipment in the digital central office. Communications with the maintenance processor are in the form of messages having a header byte and a byte indicating the length of the message. During network initialization and various recovery operations, the programs and/or the data base can be transferred from the maintenance processor to each digital satellite interface through the use of these messages.
    Type: Grant
    Filed: October 13, 1981
    Date of Patent: June 7, 1983
    Assignee: Stromberg-Carlson Corporation
    Inventors: Robert D. Hayes, Glenn L. Richards
  • Patent number: 4387455
    Abstract: Apparatus for transmission of information in digital form comprising apparatus for providing a plurality of signals coded into a multiplicity of digital code elements in accordance with a first modulation technique; and apparatus for providing a plurality of coded addresses for transmission, each of the coded addresses representing a digital code in accordance with a second modulation technique corresponding to a combination of code elements of individual ones of the plurality of signals.
    Type: Grant
    Filed: July 13, 1981
    Date of Patent: June 7, 1983
    Inventor: Nira Schwartz
  • Patent number: 4387458
    Abstract: A loop network is disclosed in which the ports have access to time slots on each of two buses. The buses carry the time slots in opposite directions. Ports are addressed by marking a bit of a time slot word on one bus and a bit of a time slot word on the other bus so that the two marked bits will arrive within a predetermined number of bit intervals of each other at the addressed port. Time slots are seized by an upstream port writing a predetermined pattern into an arriving idle time slot and by the downstream port recognizing the arrival of that predetermined pattern. A time slot may be reused during the remainder of its passage around the loop after it is rendered idle by the downstream port of a connection.
    Type: Grant
    Filed: May 28, 1981
    Date of Patent: June 7, 1983
    Assignee: Bell Telephone Laboratories, Incorporated
    Inventor: Robert L. Carbrey
  • Patent number: 4387457
    Abstract: A digital conference circuit for a digital telephone switching network is provided, connected between a receive TDM (time division multiplex) bus carrying PCM (pulse code modulation) words to the conference circuit and a transmit TDM bus carrying PCM words from the conference circuit. A memory (storage) device stores the PCM words most recently received on the receive TDM bus and decision circuitry determines, for each conferee, which two PCM words, excluding the PCM word originating from that conferee, should be read from the memory device. The two PCM words so read are attenuated in a predetermined fashion, summed, and the resultant PCM sum applied to the transmit TDM bus during an appropriate timeslot. The decision circuit makes its decision based upon the largest average magnitude of each conferee's PCM words, received at the conference circuit, during the previous frames.
    Type: Grant
    Filed: June 12, 1981
    Date of Patent: June 7, 1983
    Assignee: Northern Telecom Limited
    Inventor: Ernst A. Munter
  • Patent number: 4387459
    Abstract: In a digital transmission system, a loop-timing technique is provided for a channel bank which demultiplexes a high speed data stream into a plurality of lower rate channels, and which multiplexes a plurality of lower rate channels to a high speed data stream. Loop-timing is provided without elastic buffers by deriving stuff requests from stuff bits in the received high speed data stream, extracting a high speed clock signal from the received data stream, and applying the stuff requests and the high speed clock signal directly to the high speed multiplexer for providing stuff bits in the transmitted high speed data stream and for clocking the transmitted high speed data stream.
    Type: Grant
    Filed: June 22, 1981
    Date of Patent: June 7, 1983
    Assignee: Rockwell International Corporation
    Inventor: Charles E. Huffman
  • Patent number: 4386426
    Abstract: A telemetry system including a number of series connected modules having clock inputs and outputs and reset inputs and outputs, each module coupling an associated digital data sources to a master station via a common data bus. Circuitry is provided in each module whereby a self perpetuating reset signal from the master station and successive clock pulses from the master station actuate and deactuate the modules in sequence to multiplex data from all of the digital data sources onto the common data bus.
    Type: Grant
    Filed: November 3, 1980
    Date of Patent: May 31, 1983
    Assignee: Burlington Industries, Inc.
    Inventor: Charles D. Pugh
  • Patent number: 4386424
    Abstract: In an exemplary embodiment, subscriber lines are formed by means of light waveguides and transmit pulse-modulated TV signals in time-division multiplex. These pulse-modulated signals are converted into PAM signals at the subscriber side, from whose frequency spectrum formed by a sequence of frequency bands, respectively one frequency band arrives via a subscriber-allocated distributor line operated in frequency-division multiplex to a video receiver now being operated at the subscriber location.
    Type: Grant
    Filed: November 4, 1980
    Date of Patent: May 31, 1983
    Assignee: Siemens Aktiengesellschaft
    Inventor: Hans-Martin Christiansen
  • Patent number: 4386425
    Abstract: A switching unit for the selective transfer of bytes concurrently arriving in successive time slots over eight incoming signal paths to as many outgoing signal paths with intervening temporal and/or spatial transposition comprises a byte memory loaded by way of a series/parallel converter and read out by way of a parallel/series converter; two 8.times.8 storage matrices may alternately serve as the two converters. A routing memory, connected via a logic network to a command unit such as a microprocessor, controls the transfer and may also block the readout from the byte memory under certain conditions, specifically during an initiation procedure or where the switching unit is one of several such units forming part of a larger switching or concentration structure. In response to particular instructions from the command unit, a single byte from an incoming path may be transferred to one or all of the outgoing paths.
    Type: Grant
    Filed: May 12, 1981
    Date of Patent: May 31, 1983
    Assignee: Cselt - Centro Studi e Laboratori Telecomunicazioni S.p.A.
    Inventors: Piero Belforte, Bruno Bostica, Luciano Pilati
  • Patent number: 4383312
    Abstract: An apparatus for testing a data multiplex transmission system by providing simulated source and sink of data for the multiplex transmission system that is compatible with the multiplex system and complies with the protocol of the Input/Output modules of the multiplex system. A programmable read only memory is programmable by means of toggle and thumbwheel switches to selectively and variably control the protocol, the length, the rate, the destination and the content of the data message. A status display is connected to the programmable read only memory to indicate the current point of progression of its programmable sequence. An error detector is connected to the programmable read only memory for determining whether the memory has stalled at a point of progression and an error display is also connected to the programmable read only memory to indicate and identify the error when this stall condition has occurred.
    Type: Grant
    Filed: November 28, 1980
    Date of Patent: May 10, 1983
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventor: Robert C. Reed
  • Patent number: 4383239
    Abstract: A detector for detecting the passage of heavy objects on a roadway, wherein the detector is an elongate strip in the form of nested channel-section members, said members comprising, from the outside towards the insidea first channel section bar (1) made of a strong material;a second channel section bar (2) made of a shock-absorbing material embedded in the channel of said first bar;a third channel section bar (3) made of a strong material embedded in the channel of said second bar; anda sensor (4) embedded in the channel of said third bar.
    Type: Grant
    Filed: July 28, 1981
    Date of Patent: May 10, 1983
    Assignee: Compagnie Generale d'Automatisme
    Inventor: Richard C. Robert
  • Patent number: 4382295
    Abstract: A time slot interchanger is disclosed for selecting and buffering digital signals between buses. The arrangement is particularly useful in forming conferences in a distributed digital time division system. In one embodiment, a clock is used to generate time signals corresponding to time slots of the first bus. These signals are sequentially provided to an associative memory and when a match occurs between the provided signal and a priorly stored time slot identity, an enable signal is provided. The enable signal has a time identity with a first bus time slot and a physical identity with a particular second bus time slot. The enable signal is used to gate into a second memory the time slot signal associated with the time identity at the storage location in the second memory corresponding with the particular time slot of the second bus associated with the enable signal. The signal samples are then sequentially removed from the second memory.
    Type: Grant
    Filed: April 23, 1981
    Date of Patent: May 3, 1983
    Assignee: Bell Telephone Laboratories, Incorporated
    Inventors: Bryan S. Moffitt, Alexander R. Ross
  • Patent number: 4381507
    Abstract: An apparatus and method for obtaining an electrical signal indicative of the degree of extension of a fluid cylinder, the signal being transmitted to a remote location for use in providing a remote readout of the cylinder position. The displacement of the piston is translated into a rotational movement of a threaded rod coupled to the piston. The rod is, in turn, coupled to a potentiometer or other device that provides an electrical signal indicative of the cylinder extension.
    Type: Grant
    Filed: October 27, 1981
    Date of Patent: April 26, 1983
    Assignee: D. E. McCraw, Jr.
    Inventor: Carl L. Parmer