Patents by Inventor Hideki Tokura

Hideki Tokura 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: 6114871
    Abstract: A defect detecting apparatus for monitoring an electrical equipment for defects, the electrical equipment having a resonance frequency.
    Type: Grant
    Filed: November 17, 1997
    Date of Patent: September 5, 2000
    Assignees: Mitsubishi Denki Kabushiki Kaisha, Kansai Electric Power Co., Inc.
    Inventors: Tetsu Shiota, Hideki Tokura, Kenji Morimoto, Takaho Tanaka, Yoshiharu Kaneda, Keiichi Itoh, Ken Kimura, Shigeo Kitamura
  • Patent number: 5828227
    Abstract: An abnormality detecting method and apparatus for electrical equipment measures the frequency spectrum of a signal detected by a partial discharge sensor and detects a partial discharge signal having a frequency component in the neighborhood of a resonance frequency to detect the abnormality of the electrical equipment. The resonance frequency is determined on the basis of the electrical equipment and the measuring circuit. Where the electrical equipment is a rotating electric machine, the resonance frequency is determined on the basis of the length of the stator core, and a narrow bandpass filter circuit passes a frequency component around a resonance frequency to detect a partial discharge signal from the passed signal.
    Type: Grant
    Filed: April 30, 1997
    Date of Patent: October 27, 1998
    Assignees: The Kansai Electric Power Co., Inc., Mitsubishi Denki Kabushiki Kaisha
    Inventors: Tetsu Shiota, Hideki Tokura, Kenji Morimoto, Takaho Tanaka, Yoshiharu Kaneda, Keiichi Itoh, Ken Kimura, Shigeo Kitamura
  • Patent number: 5680059
    Abstract: The abnormality detecting method and apparatus for electric equipment measure the frequency spectrum of a signal detected by a partial discharge sensor 9, and detect a partial discharge signal having a frequency component in the neighborhood of a resonance frequency determined on the basis of the electric equipment and its measuring circuit, then detect the abnormality of the electric equipment. In a rotating electric machine particularly, the narrow band filter circuit 23 passes a frequency component around a resonance frequency determined on the basis of the length of the stator core to detect a partial discharge signal from the passed signal.
    Type: Grant
    Filed: December 20, 1994
    Date of Patent: October 21, 1997
    Assignees: The Kansai Electric Power Co., Inc., Mitsubishi Denki Kabushiki Kaisha
    Inventors: Tetsu Shiota, Hideki Tokura, Kenji Morimoto, Takaho Tanaka, Yoshiharu Kaneda, Keiichi Itoh, Ken Kimura, Shigeo Kitamura