Patents by Inventor Takashi Shikama

Takashi Shikama 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: 6311387
    Abstract: A method of manufacturing a bead inductor prevents deformation of a metal coil or dislocation of the axis position of the metal coil caused by injection pressure at the time of injecting a molten resin material from a gate. A coil is fitted onto a coil supporting pin provided on a first lower mold used for injection molding in a cavity of the mold such that the inner periphery of the coil is in close contact with the coil supporting pin. A molten, resin material is injected into the cavity. Then, the coil supporting pin and the first lower mold are removed from the molded product, and a second lower mold without a coil supporting pin is provided for replacing the first lower mold. A molten resin material is injected into the space which had been occupied by the coil supporting pin. After removing the hardened resin molded product from the mold for injection molding, the end parts of the coil are cut so as to be exposed.
    Type: Grant
    Filed: June 3, 1999
    Date of Patent: November 6, 2001
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Takashi Shikama, Masami Sugitani, Hisato Oshima
  • Patent number: 6300861
    Abstract: An organic thermistor device has a pair of outer electrodes formed facing each other on end parts of a thermistor body made of an organic thermistor material. Metallic wires extend inside and through the thermistor body transversely to the direction in which the outer electrodes face each other such that the resistance value at normal temperatures of the device can be significantly reduced. Both exposed surfaces of the thermistor body not covered by the outer electrodes and exposed end surfaces of the metallic wires not covered by the thermistor body may be all covered by an electrically insulating layer. To produce such organic thermistor devices, an elongated wire-containing member is prepared by molding an organic thermistor material by covering metallic wires extending longitudinally parallel to one another. It is then entirely covered with an electrically insulating material but portions of it are removed from a pair of longitudinally continuous external peripheral surface areas.
    Type: Grant
    Filed: September 28, 1999
    Date of Patent: October 9, 2001
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Shinichi Osada, Tomozo Yamanouchi, Yuichi Takaoka, Takashi Shikama
  • Patent number: 6275132
    Abstract: An inductor includes a coiled metal wire, an insulating molded member in which the coiled metal wire is embedded, and metal caps fitted on both ends of the insulating molded member. The metal caps are welded to both ends of the coiled metal wire. Between the metal caps and the end surfaces of the insulating molded member, spaces are defined respectively. The insulating molded member is made of, for example, resin or rubber.
    Type: Grant
    Filed: October 13, 1998
    Date of Patent: August 14, 2001
    Assignee: Murata Manufacturing Co., LTD
    Inventors: Takashi Shikama, Masami Sugitani, Takahiro Yamamoto, Hisato Oshima
  • Publication number: 20010005167
    Abstract: An electronic part in which insulating tape is adhered to lead terminals which extend from an electronic part unit so that a pitch between the terminals can remain stable and constant. The insulating tape is adhered to portions of the lead terminals in a vicinity of the unit from both sides such that the tape is placed with the terminals therebetween.
    Type: Application
    Filed: July 7, 1997
    Publication date: June 28, 2001
    Inventors: TOSHIKAZU NAKAMURA, TAKASHI SHIKAMA
  • Patent number: 6242995
    Abstract: A method of manufacturing a bead inductor includes the steps of forming a molded body of a resin material or a rubber material including a powdery magnetic substance with a conductor coil defined by a wound, coated metallic wire; cutting both ends of the molded body so as to expose the ends of the conductor coil; and attaching external terminals to the exposed ends of the conductor coil so that the external terminals are electrically connected to the conductor coil. The connection reliability between the conductor coil and the external terminals is greatly increased in the bead inductor manufactured by the method because convex portions protruding from the end surfaces of the molded body are provided on both ends of the conductor coil, which are exposed by cutting the molded body, so that the external terminals are attached and electrically connected to the convex portions.
    Type: Grant
    Filed: June 14, 1999
    Date of Patent: June 5, 2001
    Assignee: Murata Manufacturing Co., LTD
    Inventors: Takashi Shikama, Masami Sugitani, Hisato Oshima
  • Patent number: 6189204
    Abstract: A method for manufacturing a bead inductor includes the steps of forming a molded body of a resin material or a rubber material including a powdered magnetic substance, including a conductor coil defined by a wound, coated metallic wire embedded in the molded body; cutting both end portions of the molded body so as to expose end portions of the conductor coil; and attaching external terminals to the exposed end portions of the conductor coil so that the conductor coil is electrically connected to the external terminals. In order to increase the reliability of connection between the conductor coil and external terminals, both end portions of the conductor coil are immersed into a solder bath, prior to the molded body forming step, so as to include in the solder bath cutting regions of both end portions of the molded body therein such that soldered portions are formed by removing insulation coating on both end portions of the conductor coil.
    Type: Grant
    Filed: June 18, 1999
    Date of Patent: February 20, 2001
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Takashi Shikama, Masami Sugitani, Hisato Oshima
  • Patent number: 6188307
    Abstract: A positive-characteristics thermistor apparatus has an insulating case, positive-characteristics thermistor devices, planar terminals, and spring terminals. Whichever thermistor device has a lower resistance of the two thermistor devices is trimmed to have a higher resistance which is near the resistance of the other thermistor device such that the two thermistor devices have substantially the same resistance (for example, within a difference of ±1 &OHgr;). In other words, a part of an electrode of the thermistor device having a lower resistance is removed with a laser beam.
    Type: Grant
    Filed: April 21, 1998
    Date of Patent: February 13, 2001
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Takayo Katsuki, Takashi Shikama
  • Patent number: 6147330
    Abstract: A PTC thermistor element for a heating device has a main body of a layered structure having a thinner layer and a thicker layer, sandwiched between electrodes formed on the main outer surfaces facing away from each other. The thinner layer has a thickness 0.05-0.43 times that of the thicker layer and is made of a PTC thermistor material with a Curie temperature which is lower than that of the thicker layer by 20.degree. C. or more. The center of heat generation is thus shifted towards the electrode formed on the thinner layer, and a heating plate contacting it can be effectively heated.
    Type: Grant
    Filed: March 1, 1999
    Date of Patent: November 14, 2000
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Yutaka Ikeda, Takashi Shikama, Yuichi Takaoka, Kenjiro Mihara
  • Patent number: 6134771
    Abstract: An electronic part in which insulating tape is adhered to lead terminals which extend from an electronic part unit so that a pitch between the terminals can remain stable and constant. The insulating tape is adhered to portions of the lead terminals in a vicinity of the unit from both sides such that the tape is placed with the terminals therebetween.
    Type: Grant
    Filed: December 31, 1996
    Date of Patent: October 24, 2000
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Toshikazu Nakamura, Takashi Shikama
  • Patent number: 6037716
    Abstract: A degaussing circuit is formed as a series connection of a PTC element and a degaussing coil operated such that the operating frequency of the current therethrough is higher than the frequency of the power source line for the device such as a color television set in which this degaussing circuit is incorporated. This frequency conversion may be effected by a circuit which also functions to convert the alternating current from the power source line into a direct current. The degaussing circuit may further include a relay circuit for switching on and off the current through the PTC element and the degaussing coil.
    Type: Grant
    Filed: November 9, 1998
    Date of Patent: March 14, 2000
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Takashi Shikama, Yuichi Takaoka
  • Patent number: 5798685
    Abstract: A positive-characteristics thermistor apparatus has an insulating case, positive-characteristics thermistor devices, planar terminals, and spring terminals. Whichever thermistor device has a lower resistance of the two thermistor devices is trimmed to have a higher resistance which is near the resistance of the other thermistor device such that the two thermistor devices have substantially the same resistance (for example, within a difference of .+-.1.OMEGA.). In other words, a part of an electrode of the thermistor device having a lower resistance is removed with a laser beam.
    Type: Grant
    Filed: February 29, 1996
    Date of Patent: August 25, 1998
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Takayo Katsuki, Takashi Shikama
  • Patent number: 5270521
    Abstract: In a heating apparatus including a plate-shaped positive temperature coefficient thermistor having a pair of electrode films, a pair of terminal plates of an elastic metal material are provided on the pair of electrode films of the thermistor, and there is further provided a spacer including a mounting through-hole which passes through the spacer in a thickness direction thereof. The spacer receives the thermistor in the mounting through-hole so as to position the thermistor therein between the pair of terminal plates. Each terminal plate comprises at least one extending portion extending in a longitudinal direction thereof from one portion of one end thereof, and the extending portion comprises a stopper piece which is folded toward the spacer, the stopper piece including a hook-shaped engaging stopper at an end of the stopper piece.
    Type: Grant
    Filed: February 24, 1992
    Date of Patent: December 14, 1993
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Takashi Shikama, Tomoyuki Yamamoto, Kiyofumi Torii
  • Patent number: 5210516
    Abstract: A PTC thermistor has its substrate entirely coated with an insulating glass material except for the area where a silver electrode is formed. Such a thermistor may be produced by coating a substrate with an insulating glass material, forming a silver layer on the coated substrate and fusing the silver layer with a part of the glass material so as to form an electrode adhering to the substrate. An underelectrode may be provided between the substrate and such an electrode. A resistor is formed by encasing such a PTC thermistor with a pair of spring terminals for supporting the thermistor therebetween.
    Type: Grant
    Filed: February 22, 1991
    Date of Patent: May 11, 1993
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Takashi Shikama, Yuichi Takaoka, Takayo Katsuki, Tomoaki Tadokoro
  • Patent number: 4954692
    Abstract: A positive temperature coefficient thermistor device for use in a heating apparatus includes a board-type positive temperature coefficient thermistor element and a first and a second radiator for radiation disposed adjacent a front and a rear surface of the thermistor element, respectively. Each of the first and second radiators has a pair of fitting flanges which are respectively arranged on a pair of opposed sides of each radiator. Such fitting flanges are oriented with their longitudinal ends at right angles to a flow direction of air to be heated by the positive temperature coefficient thermistor device. Corresponding fitting flanges of the first and second radiators are engaged with each other by a pair of pin members which are inserted between respective pairs of opposing surfaces of the facing flanges to hold the flanges in a fixed relation to each other. The thermistor element is contained in a space surrounded by the first and second radiators.
    Type: Grant
    Filed: September 9, 1988
    Date of Patent: September 4, 1990
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Takashi Shikama, Asami Wakabayashi, Kiyofumi Torii
  • Patent number: 4931626
    Abstract: A PTC thermistor device includes a heat generator containing a PTC thermistor unit, and heat radiators thermally coupled thereto. Each of heat radiators includes a plate, one main surface of which is adhered onto the heat generator, and a number of fins integrally formed on the other main surface of the plate. Since the plates of the heat radiators are thermally coupled to the heat generator, respectively, heat generated by the PTC thermistor unit is radiated from the fins through the plates. Free ends of respective sets of fins form opening portions, and guide plates are disposed above and below the respective opening portions so as to prevent air from escaping through the opening portions. If the guide plates are movable guide plates and are moved, an opening degree of each opening portion covered by each of the movable guide plates is changed such that temperature of warm air blown-out from an air outlet side can be adjusted or controlled.
    Type: Grant
    Filed: March 10, 1989
    Date of Patent: June 5, 1990
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Takashi Shikama, Asami Wakabayashi, Kiyofumi Torii
  • Patent number: 4894637
    Abstract: A positive temperature coefficient thermistor device has a case, a positive temperature coefficient thermistor element which is disposed in the case, a pair of first terminals which is disposed in the case to be in contact with corresponding electrodes of the thermistor element, a pair of second terminals which is disposed on the case and is associated with the first terminals, and pin members electrically and mechanically connecting the first terminals with the second terminals through an outer wall of the case.
    Type: Grant
    Filed: September 6, 1988
    Date of Patent: January 16, 1990
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Yoshihiro Yamada, Yuichi Takaoka, Masahito Mihara, Takashi Shikama
  • Patent number: 4831241
    Abstract: A method of assembling a cylindrical heater whereby the cylindrical heater includes a positive temperature coefficient thermistor element sandwiched between a pair of terminal members at its opposite electrode surfaces. The thermistor element is inserted into an opening formed in a cylindrical case of a material having heat-shrinkability and thereafter, the cylindrical case is caused to shrink by heating for holding the positive temperature coefficient thermistor element and the terminal members under pressure so as to obtain thermal connection thereof.
    Type: Grant
    Filed: December 23, 1985
    Date of Patent: May 16, 1989
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Takashi Shikama, Toshikazu Nakamura, Kiyofumi Torii
  • Patent number: 4516054
    Abstract: A light bulb protection arrangement including a lamp, a socket, and a junction socket having a base portion and a socket portion so as to attach the light bulb to the socket. The junction socket includes a connecting terminal, a first terminal to be connected to the central electrode of the socket, a second terminal to be connected to the central electrode of the light bulb, and a negative temperature coefficient thermistor connected between the first terminal and the second terminal.
    Type: Grant
    Filed: June 30, 1982
    Date of Patent: May 7, 1985
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Takashi Shikama, Tomoyuki Yamamoto, Atsuo Yokota
  • Patent number: 4504817
    Abstract: A PTC thermistor device includes three PTC thermistors aligned and disposed in a heat transmission relation to each other such that the center PTC thermistor provides heat to the other PTC thermistors which are so connected as to define a part of path for the demagnetizing current. The two PTC thermistors positioned on the opposite sides of the center PTC thermistor increase their temperature rapidly so that a rapid and effective attenuation of demagnetizing current can be obtained.
    Type: Grant
    Filed: April 5, 1982
    Date of Patent: March 12, 1985
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Takashi Shikama, Tomoyuki Yamamoto, Yuichi Takaoka
  • Patent number: 4422120
    Abstract: A combination starter-protector device for a winding circuit of a dynamoelectric motor comprises a housing structure having a perforated wall dividing the interior of the housing structure into starter and protector compartments. The starter compartment accommodates therein a positive temperature coefficient thermistor while the protector compartment accommodates therein a bimetal switch. The housing structure has two sets of terminals, one set of the terminals being adapted to be connected to the winding circuit of the motor whereas the other set of the terminals are adapted to be connected to a power source. The distance between the thermistor and the bimetal switch may be adjustable by the employment of a spacer element.
    Type: Grant
    Filed: October 9, 1981
    Date of Patent: December 20, 1983
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Takashi Kobayashi, Takashi Shikama, Tomoyuki Yamamoto, Atsuo Yokota