Patents by Inventor Noboru Nagumo

Noboru Nagumo 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: 6189494
    Abstract: When an engine is operated at a low and medium speed range, since the combustion pressure introduced into a pressure chamber of a valve drive unit is relatively small, a control valve is projected toward the cylinder by the biasing force of a spring so as to lower the upper edge of the exhaust port. At the same time, in conjunction with this motion of the control valve, a resonance chamber is opened so as to communicate between the resonance chamber and the exhaust port, thereby the engine power is increased. When the engine is operated at a high speed range, since the combustion pressure is relatively large, the control valve goes away from the cylinder so as to enlarge the exhaust port and at the same time, in conjunction with this motion of the control valve, the resonance chamber is closed, thereby the engine power is increased.
    Type: Grant
    Filed: May 14, 1999
    Date of Patent: February 20, 2001
    Assignee: Fuji Jukogyo Kabushiki Kaisha
    Inventors: Noboru Nagumo, Toshihiro Nagano, Kentaro Hirota