Patents by Inventor Takayoshi Ishikawa

Takayoshi Ishikawa has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 6256139
    Abstract: A plastic optical fiber continuous optical amplifier for continuously amplifying signal lights includes an exciting light tube with a double tube structure formed of an inner tube and an outer tube, and a plastic optical fiber (POF) coaxially provided inside the inner tube of the exciting light tube. The POF includes a core having an induced emission material therein and a larger refractive index, and a clad for holding the core and having a smaller refractive index than that of the core. The core and the clad are coaxially provided to the POF. It is preferable that electrodes of the exciting light tube have a ring shape to effectively excite.
    Type: Grant
    Filed: April 6, 1999
    Date of Patent: July 3, 2001
    Assignees: Nippon Aleph Corporation
    Inventors: Kazuhito Fujii, Suguru Horinouchi, Takayoshi Ishikawa
  • Patent number: 5832578
    Abstract: The present invention relates to a filter employed in a radio communication apparatus and has as an object to prevent characteristics of the filter from degradation by increasing unloaded Q of strip line resonators of the filter.
    Type: Grant
    Filed: November 22, 1995
    Date of Patent: November 10, 1998
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Naoki Yuda, Hiroshi Takahashi, Takayoshi Ishikawa, Thuyoshi Himori, Tomoaki Ieda
  • Patent number: 5489881
    Abstract: The present invention relates to a filter employed in a radio communication apparatus and has as an object to prevent characteristics of the filter from degradation by increasing unloaded Q of strip line resonators of the filter.
    Type: Grant
    Filed: May 31, 1994
    Date of Patent: February 6, 1996
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Naoki Yuda, Hiroshi Takahashi, Takayoshi Ishikawa, Thuyoshi Himori, Tomoaki Ieda
  • Patent number: 5343355
    Abstract: The safety shutter device comprises, a fixed shutter blade (19) provided on the front face of the lead conductor carrying member (11), at least one shutter driving unit accommodated in an insertion space (18) which is between the lead conductor carrying members (11) or between one of the lead conductor carrying member and the side wall of a base frame (1) and secured there by the fixed shutter blades, and a pair of movable shutter blades (27) provided on the shutter driving units to be actuated by the pushed-in and drawn-out operation of the circuit breaker (2).
    Type: Grant
    Filed: June 24, 1993
    Date of Patent: August 30, 1994
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Takayoshi Ishikawa
  • Patent number: 5337210
    Abstract: In a drawout type switch gear, rotation of the lead screw (7) is locked automatically at the connected position and the test position of the drawout/push-in unit (R), symbols or marks for representing these positions are provided on an indicator plate (18), which is driven laterally behind the front panel of the circuit breaker by a cam-rod type motion-direction transforming link (23, 19, 21, 18) and is arranged to be visible through display windows (15c) provided on the front panel (15). The insertion of the detachable handle (111) into a polygonal hole (7a) provided on the front end of the lead screw (7) is Inhibited by a blocking arm (110a), which is interlocked with a lock plate (16) driven by motion of the drawout/push-in unit (R).
    Type: Grant
    Filed: September 15, 1992
    Date of Patent: August 9, 1994
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Takayoshi Ishikawa, Shinsaku Yamasaki
  • Patent number: 5324088
    Abstract: A suspension apparatus for suspending a truck-type circuit breaker or the like when the circuit breaker is put on or taken off a truck of a switchboard frame comprises a suspension adapter to be engaged with a first hollow provided on a side face of the circuit breaker and a stopper provided on the suspension adapter to be engaged with a second hollow provided on a top face of the circuit breaker.
    Type: Grant
    Filed: February 23, 1993
    Date of Patent: June 28, 1994
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Tsukasa Iio, Takayoshi Ishikawa
  • Patent number: 5309317
    Abstract: The sliding mechanism (50) of a drawout type switchgear has a first slide arm (5) which is slidably supported by the upper and lower support rails (3A, 3B) and a second slide arm (7) which is slidably supported by the first slide arm (5). The second slide arm (7) is interlocked with the first slide arm (5) by a lock plate (12) when the first slide arm (5) is sliding from a connected position to a final drawout position of the first slide arm (5). When the first slide arm (5) reaches the final drawout position of the first slide arm (5), the interlocked second slide arm (7) is released by rotation of the lock plate (12).
    Type: Grant
    Filed: November 24, 1992
    Date of Patent: May 3, 1994
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Takayoshi Ishikawa
  • Patent number: 4795990
    Abstract: In a bridge T type trap circuit having CR delta connection circuit and a variable LC tank circuit, the CR delta connection circuit is connected to the LC tank circuit via a variable inductor (19; 31, 33; 40). In one embodiment, a capacitor (18) is coupled with the variable inductor (19; 31, 33) to form another LC tank circuit. In another embodiment, a variable inductor (39) used in the first-mentioned LC tank circuit has a tap which is grounded. Impedance values of the first-mentioned LC tank circuit and the variable inductor (40) are adjusted so that absolute values of real and imaginary parts thereof have a given relationship. A resistor (22) of the CR delta connection circuit is used in common in a double-trap structure having two CR delta connection circuits and two series circuits each having two LC tank circuits.
    Type: Grant
    Filed: April 17, 1986
    Date of Patent: January 3, 1989
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Takayoshi Ishikawa, Yasuhiko Yoshida
  • Patent number: 4655538
    Abstract: A terminal connecting device has a plurality of movable contacts which are biased toward each other by springs to an extent limited by a spacer carried by the frame. The device is easily assembly by fitting shafts through bores in the contacts and using spring holders inserted between pairs of contacts and locked by wedges to exert a biasing force urging opposed contacts together. The shafts are held by support and frame members having open recesses, as opposed to bores, therein.
    Type: Grant
    Filed: November 20, 1985
    Date of Patent: April 7, 1987
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Kiyoshi Eguchi, Takayoshi Ishikawa, Shigemi Tamaru, Yasushi Genba, Tsutomu Sera
  • Patent number: 4630074
    Abstract: A multiple stylus electrode for discharge printing body for discharge printing comprises a body mainly of a resin having a thermal deformation temperature of at least 200.degree. C., having a plurality of electrode elements of an elongate core coated with borosiloxane resin in a parallel array extending from said electrode body.
    Type: Grant
    Filed: March 13, 1985
    Date of Patent: December 16, 1986
    Assignees: Nippon Aleph Co. Ltd., Gestetner International Limited
    Inventors: Tamotsu Horinouchi, Takayoshi Ishikawa, Tsugutoshi Tanaka, Masahiro Ono
  • Patent number: 4497992
    Abstract: The disclosure describes an air circuit breaker including a compression coil; a second spring holder to compress the compression coil in the axial direction thereof; and a first spring holder which is subjected to the compression force of the compression coil, the second spring holder being constructed in such a manner that it is formed of a plate material in a rectangular shape, a pair of projected pieces are provided on both sides of the plate material, and a pin is held to pass between the pair of projected pieces in the direction of thickness of the plate so as to be able to support one end of the energy accumulating spring at four points with the pair of projected pieces and the pin in a compressible manner. After compression of the energy accumulating spring by pressure application thereto, its pressure application is released to stretch the energy accumulating spring so as to close a pair of contact points through the first and second spring holders.
    Type: Grant
    Filed: January 25, 1983
    Date of Patent: February 5, 1985
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Toshihiko Kodera, Kiyoshi Eguchi, Takayoshi Ishikawa, Yasushi Genba, Shigemi Tamaru, Susumu Satou
  • Patent number: 4486814
    Abstract: A drawer-type circuit breaker of the type adapted to be disposed in an engaged and disengaged position within a housing and a disengaged position outside the housing on extendable support rails is provided with latches which will prevent the extension of the guide rails until the circuit breaker is moved from the engaged position to the disengaged position within the housing. The movement of the circuit breaker to the disengaged position operates the latches to permit extension of the support rails while still preventing movement of the circuit breaker onto the support rails. Movement of the support rails to the fully extended position allows the latches to be released by movement of the circuit breaker to allow the circuit breaker to be withdrawn out of the housing onto the support rails.
    Type: Grant
    Filed: August 22, 1983
    Date of Patent: December 4, 1984
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Takayoshi Ishikawa, Yasushi Genba, Shigemi Tamaru, Kiyoshi Eguchi
  • Patent number: 4475021
    Abstract: The present invention describes an air circuit breaker including, in combination, a rotational shaft connected with a motor, a cam which rotates in one direction through a ratchet by a handle operation to accumulate energy in an energy accumulating spring for contact closure, an engaging part provided on the outer periphery of the rotational shaft, and a latch which slides on and along the engaging part of the rotational shaft such that the latch means remains disengaged from the engaging part when the cam is rotated by the handle operation so that the rotational shaft remains stationary, and which causes the cam to rotate together with the rotational shaft by engaging the engaging part of the rotational shaft when the rotational shaft is rotated in one and the same direction by the driving motor.
    Type: Grant
    Filed: January 25, 1983
    Date of Patent: October 2, 1984
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Yoshinori Mochizuki, Kiyoshi Eguchi, Takayoshi Ishikawa, Yasushi Genba, Shigemi Tamaru, Masayuki Okada
  • Patent number: 4468081
    Abstract: A terminal assembly for a circuit interrupter has a plurality of pairs of metallic spaced parallel flat load terminals with the flat surfaces of the terminals of a pair opposed to each other, the pairs of terminals being positioned side-by-side with spaces therebetween, there being one pair for each phase of the interrupter. Two side walls of insulating material are provided between each side-by-side pair of terminals and abutting each other, and two end walls of insulating material are provided on the outside of the outermost pairs of the terminals. The side walls and end walls have grooves therein holding the side edges of the terminals, the terminals projecting outwardly from between the side walls and end walls. Bolts extend through aligned bolt receiving holes.
    Type: Grant
    Filed: July 15, 1982
    Date of Patent: August 28, 1984
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Yasushi Genba, Shigemi Tamaru, Takayoshi Ishikawa, Kiyoshi Eguchi, Hideshi Takashita
  • Patent number: 4468533
    Abstract: The present invention describes an air circuit breaker having a bounce preventive device which is provided on the direction changing lever interposed between the link mechanism to drive the contact opening and closing mechanism for closure of the contact and the contact opening and closing mechanism, so as to prevent the bouncing phenomenon from occuring at the time of the OFF-operation, thereby making it possible to secure accurate circuit breaking action.
    Type: Grant
    Filed: January 25, 1983
    Date of Patent: August 28, 1984
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Toshihiko Kodera, Kiyoshi Eguchi, Takayoshi Ishikawa, Yasushi Genba, Shigemi Tamaru, Susumu Satou
  • Patent number: 4468082
    Abstract: The disclosed terminal assembly for a circuit interrupter comprises three pairs of opposite source and load terminals, each pair being carried on both lateral sides by a pair of first and second side plates by having each lateral side and a recess on that side engaging an associated groove and a raised portion on the front surface of each side plate respectively and connected to adjacent pairs of the opposite source and load terminals through different pairs of the first and second side plates interconnected back to back. All the terminals and side plates are assembled into a unitary structure between two metallic plates by means of bolts and nuts. A supporting strut includes two notches fitted onto the lateral surfaces of end portions of each pair of the opposite source and load terminals and is disposed on each of the side plates.
    Type: Grant
    Filed: July 15, 1982
    Date of Patent: August 28, 1984
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Shigemi Tamaru, Yasushi Genba, Takayoshi Ishikawa, Kiyoshi Eguchi, Hideshi Takashita
  • Patent number: 4446347
    Abstract: An arc-suppressing apparatus for a circuit breaker has a pair of side plates having a plurality of first and second grooves formed therein, the second grooves being shallower than the first grooves and extending linearly from the ends of the first grooves to an end of each of the side plates. The side plates are separated by a spacing strut and loosely connected by a bolt and nut so that a space exists between the plates which is large enough to allow a plurality of grids to slide along the second grooves into the first grooves. Thereafter, the nut and bolt are tightened to firmly secure the grids in the first grooves.
    Type: Grant
    Filed: April 5, 1982
    Date of Patent: May 1, 1984
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Kiyoshi Eguchi, Takayoshi Ishikawa, Shigemi Tamaru, Yasushi Genba, Toshihiko Kodera
  • Patent number: 4422059
    Abstract: A band-pass filter comprising a shielded housing having a first and a second chamber. First and second quarter-wave resonators are disposed in the first and second chambers, respectively, for coupling with input energy and delivering output energy. First and second parallel-circuit resonators are disposed in the first and second chambers, respectively, to provide interstage coupling between resonators in the respective chambers. Each of the resonators comprises a multilayered coil structure on a finned bobbin juxtaposed on a common insulative substrate so that its coil portions are separately wound on adjacent fins of the bobbin. Each of the quarter-wave resonators has one end being short-circuited by coupling with the housing and the other end being open-circuited. Each of the parallel-circuit resonators includes a capacitor to form a parallel resonance circuit and has one end coupled to one end of the other parallel-circuit resonator at a point outside of the housing.
    Type: Grant
    Filed: March 31, 1982
    Date of Patent: December 20, 1983
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Tsuneharu Fuji, Masakatsu Tsumura, Takayoshi Ishikawa
  • Patent number: 4412112
    Abstract: A drawer-type circuit breaker of the type adapted to be disposed in an engaged and disengaged position within a housing and a disengaged position outside the housing on extendable support rails is provided with latches which will prevent the extension of the guide rails until the circuit breaker is moved from the engaged position to the disengaged position within the housing. The movement of the circuit breaker to the disengaged position operates the latches to permit extension of the support rails while still preventing movement of the circuit breaker onto the support rails. Movement of the support rails to the fully extended position allows the latches to be released by movement of the circuit breaker to allow the circuit breaker to be withdrawn out of the housing onto the support rails.
    Type: Grant
    Filed: April 13, 1982
    Date of Patent: October 25, 1983
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Takayoshi Ishikawa, Yasushi Genba, Shigemi Tamaru, Kiyoshi Eguchi
  • Patent number: D347623
    Type: Grant
    Filed: January 3, 1992
    Date of Patent: June 7, 1994
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Masakatsu Suzuki, Fumiyuki Hisatsune, Takayoshi Ishikawa, Tsukasa Iio, Yasushi Genba, Kouhei Fujiwara, Shinsaku Yamasaki, Hiroshi Okashita