Patents by Inventor Yasuo Tagawa

Yasuo Tagawa 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: 5357934
    Abstract: An apparatus for controlling pressures within a fuel tank is provided in a purge pipe connected between the fuel tank and a canister. In an operating condition of an engine, a diaphragm in a control valve provided in a purge pipe between the fuel tank and the canister is moved upward by an intake negative pressure to decrease a set load of a spring, and in a stopped condition of the engine, the diaphragm moves downward to increase the set load of the spring. As a result, in the operating condition of the engine, a valve member is opened when a pressure within the fuel tank exceeds a lower predetermined level. In the stopped condition of the engine, the valve member is opened when a pressure within the fuel tank exceeds a higher predetermined level. Therefore, even when a leakage accident occurs in the operating condition of the engine, evaporated fuel is prevented as much as possible from being discharged in a large amount into the atmosphere.
    Type: Grant
    Filed: October 15, 1993
    Date of Patent: October 25, 1994
    Assignee: Nippondenso Co., Ltd.
    Inventors: Hisashi Iida, Yasuo Tagawa
  • Patent number: 4257458
    Abstract: In a reed valve of the type having a base formed with one or more apertures through which flows a fluid, a shock absorbing seat attached to the upper surface of the base so as to surround the one or more apertures at the inner peripheral edge thereof, and a reed having one end securely fixed to the base, whereby the reed is forced to move to seat on the seat, thereby closing the one or more apertures and to move away therefrom, thereby opening the one or more apertures, at least a portion of the inner peripheral edge of the seat which engages with the free end portion of the reed is spaced outwardly away from the upper edge of the aperture by a suitable distance and is beveled or curved.
    Type: Grant
    Filed: March 14, 1978
    Date of Patent: March 24, 1981
    Assignees: Nippondenso Co., Ltd., Toyota Jidosha Kogyo Kabushiki Kaisha
    Inventors: Takashi Kondo, Yasuo Tagawa, Kiyohiko Mizuno, Nobutoshi Tsuboi