Patents by Inventor Fumihiko Ishikawa

Fumihiko 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: 5313130
    Abstract: A superconduction bearing is provided in which the load capacity and rigidity of a rotary member are improved, run-out of the rotary member is prevented to support the rotary member in a stable, non-contacting manner, and manufacturing cost is reduced. The superconduction bearing includes a rotary member and a disk formed on the rotary member. The disk has permanent magnets provided thereon. The permanent magnets are magnetized to have opposite poles on top and bottom sides thereof. A permanent magnet section is thus formed by the disk and the permanent magnets. Superconductors are concentrically provided for rotatably supporting the rotary member. The permanent magnet section and the superconductor section are positioned opposite to each other. The width and thickness of the permanent magnets are set to 5 to 10 times the distance between the permanent magnet section and the superconductor section.
    Type: Grant
    Filed: July 30, 1992
    Date of Patent: May 17, 1994
    Assignees: Kabushiki Kaisha Shikoku Sogo Kenkyusho, Shikoku Denryoku Kabushiki Kaisha, Mitsubishi Denki Kabushiki Kaisha, Seiko Epson Corporation
    Inventors: Motoaki Shibayama, Takenori Tada, Terutsugu Oyama, Fumihiko Ishikawa, Hiromasa Higasa
  • Patent number: 5289147
    Abstract: An image forming apparatus includes a housing, a mechanism, mounted in the housing, for forming images on a medium, an operation panel formed on the housing, the mechanism being driven in accordance with an operating instruction input from the operation panel by an operator, a microphone, provided in the housing, for detecting a noise generated by a driving of the mechanism, and a noise canceling unit for outputting an acoustic wave to an area adjacent to the operation panel of the housing, the acoustic wave being generated based on the noise detected by the microphone so that the acoustic wave and a noise present in the area cancel out, whereby the noise present in the area is reduced.
    Type: Grant
    Filed: May 5, 1992
    Date of Patent: February 22, 1994
    Assignee: Ricoh Company, Ltd.
    Inventors: Tadao Koike, Kenji Fukumizu, Hiroo Kitagawa, Fumihiko Ishikawa, Tkaaki Yanagisawa, Satoshi Kanda
  • Patent number: 5245385
    Abstract: An image forming apparatus reduces the level of noise escaping therefrom via an opening. The noise is generated from a motor which drives an image forming part in the image forming apparatus, from a radiator fan which radiates heat inside the apparatus to the outside via the opening, and from an exhaust fan which passes harmful air through a filter and then exhausts harmless air to the outside via the opening. The image forming apparatus generates a predetermined sound wave and collides it with the noise so that the predetermined sound wave and noise cancel each other out.
    Type: Grant
    Filed: December 19, 1991
    Date of Patent: September 14, 1993
    Assignee: Ricoh Company, Ltd.
    Inventors: Kenji Fukumizu, Hiroo Kitagawa, Fumihiko Ishikawa, Tadao Koike, Takaaki Yanagisawa, Satoshi Kanda
  • Patent number: 5222568
    Abstract: The present invention relates to an improvement of the driving characteristics of an electric vehicle in which each of the driving wheels is adapted to be driven by its individual driving motor, and more particularly, firstly to an improvement of the driving characteristics of the electric vehicle without complication of the mechanical structure thereof and secondly to an improvement of the motion characteristics of the electric vehicle by simplifying the structure of steering wheel also having a function of driving wheel and by increasing the degree of freedom of the swiveling action of the steering wheel.In order to achieve these objects, according to the present invention, each of the driving wheels arranged at both sides of the electric vehicle is provided with an independently controlled driving motor and such a structure is applied also to the steering wheels.
    Type: Grant
    Filed: January 29, 1991
    Date of Patent: June 29, 1993
    Assignees: Kabushiki Kaisha Shikoku Sogo Kenkyujo, Kazunobu Sato
    Inventors: Hiromasa Higasa, Fumihiko Ishikawa, Shigenori Matsumura, Hidetoshi Nasu, Kazunobu Sato
  • Patent number: 5162964
    Abstract: A connection control device for controlling the connection of a small generator unit, which is installed at the consumer's location, to an electric power system. The connection control device detects variations in frequency components which result from interruptions in the distribution of electric power to the consumer from the electric power system. When a significant variation in a frequency component is present, the connection control device disconnects the consumer from the electric power system in order to prevent injury to line workers.
    Type: Grant
    Filed: August 13, 1990
    Date of Patent: November 10, 1992
    Assignees: Nissin Electric Co., Ltd., Shikoku Research Institute Incorporated, Shikoku Electric Power Co., Inc.
    Inventors: Hiromasa Higasa, Fumihiko Ishikawa, Shigenori Matsumura, Soichi Yamanaka
  • Patent number: 5111377
    Abstract: In a power interconnection system between an electric power system and a power converter which makes AC power from a DC power source, a positive feed-back loop is constituted so as to include a frequency deviation detector, a band-pass filter, an inert zone circuit, an amplifier, an adder, a phase controller, an inverter controller, an inverter and an interconnection reactor. Thereby a sufficiently great frequency fluctuation is made after opening of a branch line switch, so as to produce a frequency abnormality signal to be given to a disconnection switch; and disconnection is made certainly.
    Type: Grant
    Filed: March 1, 1991
    Date of Patent: May 5, 1992
    Assignees: Shikoku Research Institute Incorporated, Mitsubishi Denki Kabushiki Kaisha
    Inventors: Hiromasa Higasa, Fumihiko Ishikawa, Shigenori Matsumura, Sueo Sakata, Masayoshi Kumano
  • Patent number: 5099145
    Abstract: A system disconnection detection circuit for a distributed location power source having a generating element and an invertor for converting a generated output from the generating element into an AC output superimposes a selected signal on the AC output of the invertor. The circuit detects system disconnection on the output side of the invertor on the basis of the AC output of the invertor on which the selected signal has been superimposed.
    Type: Grant
    Filed: October 23, 1990
    Date of Patent: March 24, 1992
    Assignees: Fuji Electric Co., Ltd., Shikoku Research Institute Incorporated
    Inventors: Hiromasa Higasa, Fumihiko Ishikawa, Shigenori Matsumura, Takeshi Takemura, Toshihisa Shimizu
  • Patent number: 4697136
    Abstract: An inverter system is disclosed for inputting an alternating current and a direct current in combination. This inverter system comprises an AC-DC converter to convert a received AC electric power from an AC electric power source to a DC electric power; a DC-AC converter to convert a thus converted DC electric power and a DC electric power from a DC electric power source to an AC electric power; a first switching means to open or close an electric circuit between an output side of the DC-AC converter and a first load; a second switching means to open or close an electric circuit between the AC electric power source to which a second load is connected and the output side of the DC-AC converter; and a controlling means for controlling opening and closing of the first and second switching means. When a electric power consumption of the first load is larger than an output of the DC electric power source, the controller closes the first switching means and opens the second switching means.
    Type: Grant
    Filed: December 1, 1986
    Date of Patent: September 29, 1987
    Assignee: Shikoku Denryoku Kabushiki Kaisha
    Inventor: Fumihiko Ishikawa