Patents by Inventor Ichirou Tokunaga

Ichirou Tokunaga 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: 6496003
    Abstract: A magnet is provided on a detection member that moves on a straight line. A Hall element serving as a magneto-electric element is provided on a fixed member that opposes the magnet. A surface of the magnet that opposes the Hall element is formed into a radius or trapezoidal shape. With this arrangement, linear outputs can be obtained at any rotational angles even when a rotator rotates a plurality of times.
    Type: Grant
    Filed: August 9, 2000
    Date of Patent: December 17, 2002
    Inventors: Hirofumi Okumura, Ichirou Tokunaga
  • Patent number: 6456065
    Abstract: A rotational angle detecting device includes a rotation detecting section for outputting sinusoidal first and second detection signals as a result of the rotation of a rotor connected to a rotary member, a storage section for updating and storing the first and second detection signals, and a controlling section. The first and second detection signals have constant amplitudes, have the same periods, and have wavelengths which are output of phase. The controlling section compares the amplitude values of most recent first and second detection signals output from the rotation detecting section, and determines whether or not the amplitude values fall within proper ranges. When the controlling section determines that they fall within the proper ranges, a piece of detection information which is created based on the most recent first and second detection signals is supplied to a controller.
    Type: Grant
    Filed: December 7, 2000
    Date of Patent: September 24, 2002
    Assignee: Alps Electric Co., Ltd.
    Inventors: Toshiyuki Hoshi, Hironori Kato, Yoshio Sanpei, Hirofumi Okumura, Ichirou Tokunaga, Toshio Ogawa
  • Patent number: 6452382
    Abstract: The encoder of the present invention includes at least a pair of giant magnetoresistive effect elements, in which the giant magnetoresistive effect elements to be paired are formed on a substrate in a state that the elements are connected mutually electrically with the orientations of magnetization axes of the pinned magnetic layers each facing the same direction in parallel, a magnetic coding member is rotatably supported to face the giant magnetoresistive effect elements on the substrate, and the magnetic coding member has a plurality of magnetic poles formed along the direction of rotation of itself.
    Type: Grant
    Filed: July 12, 1999
    Date of Patent: September 17, 2002
    Assignee: Alps Electric Co., Ltd.
    Inventors: Ichirou Tokunaga, Seiji Kikuchi, Yoshito Sasaki, Takashi Hatanai
  • Patent number: 6329818
    Abstract: The present invention is characterized in that a first giant magnetoresistive effect element and a second giant magnetoresistive effect element are provided along a first straight line with the magnetization of the pinned magnetic layer c oriented in a fixed direction, and that a third giant magnetoresistive effect element and a fourth giant magnetoresistive effect element are provided along a second straight line, which is parallel to the first straight line, with the magnetization of the pinned magnetic layer oriented 180° opposite to the directions of magnetization of the pinned magnetic layers in the first and second giant magnetoresistive effect elements.
    Type: Grant
    Filed: July 14, 1999
    Date of Patent: December 11, 2001
    Assignee: Alps Electric Co., Ltd.
    Inventors: Ichirou Tokunaga, Seiji Kikuchi, Yoshito Sasaki, Takashi Hatanai
  • Publication number: 20010004720
    Abstract: A rotational angle detecting device includes a rotation detecting section for outputting sinusoidal first and second detection signals as a result of the rotation of a rotor connected to a rotary member, a storage section for updating and storing the first and second detection signals, and a controlling section. The first and second detection signals have constant amplitudes, have the same periods, and have wavelengths which are output of phase. The controlling section compares the amplitude values of most recent first and second detection signals output from the rotation detecting section, and determines whether or not the amplitude values fall within proper ranges. When the controlling section determines that they fall within the proper ranges, a piece of detection information which is created based on the most recent first and second detection signals is supplied to a controller.
    Type: Application
    Filed: December 7, 2000
    Publication date: June 21, 2001
    Applicant: Alps Electric Co., Ltd.
    Inventors: Toshiyuki Hoshi, Hironori Kato, Yoshio Sanpei, Hirofumi Okumura, Ichirou Tokunaga, Toshio Ogawa
  • Patent number: 6175296
    Abstract: The potentiometer of the present invention includes at least a pair of giant magnetoresistive effect elements, in which the giant magnetoresistive effect elements to be paired are formed on a substrate in a state that the elements are connected mutually electrically with the orientations of magnetization axes of the pinned magnetic layers facing 180° opposite each other, and a magnetic coding member is rotatably provided to face the giant magnetoresistive effect elements on the substrate, the magnetic coding member is disposed in such a manner that the center of rotation of the magnetic coding member passes through an intermediate position of the giant magnetoresistive effect elements to be paired, and the magnetic coding member has at least two magnetic poles formed along the direction of rotation of itself.
    Type: Grant
    Filed: July 12, 1999
    Date of Patent: January 16, 2001
    Assignee: Alps Electric Co., Ltd.
    Inventors: Ichirou Tokunaga, Seiji Kikuchi, Yoshito Sasaki, Takashi Hatanai