Patents by Inventor Iwao Masumoto

Iwao Masumoto 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: 5103774
    Abstract: An improved thermostat arrangement for an internal combustion engine and an associated cooling system for the engine. The thermostat is designed so as to introduce a swirl in the thermostat housing to reduce pulsations in the coolant. In addition, the engine disclosed has its cooling jacket in such a way that the water pump is at one end of the engine and the thermostat is at the other end of the engine so as to facilitate transverse mounting of the engine.
    Type: Grant
    Filed: September 7, 1990
    Date of Patent: April 14, 1992
    Assignee: Yamaha Hatsudoki Kabushiki Kaisha
    Inventors: Akira Hirata, Iwao Masumoto
  • Patent number: 5048471
    Abstract: An improved compact high performance induction system for a V-type engine. The induction system includes a pair of plenum chambers each disposed above a respective one of the cylinder heads and each plenum chamber is provided with runners that serve common intake passages of both the adjacent and remotely positioned cylinder heads.
    Type: Grant
    Filed: September 18, 1990
    Date of Patent: September 17, 1991
    Assignee: Yamaha Hatsudoki Kabushiki Kaisha
    Inventors: Osamu Takii, Iwao Masumoto
  • Patent number: 4976462
    Abstract: An improved thermostat arrangement for an internal combustion engine and an associated cooling system for the engine. The thermostat is designed so as to introduce a swirl in the thermostat housing to reduce pulsations in the coolant. In addition, the engine disclosed has its cooling jacket in such a way that the water pump is at one end of the engine and the thermostat is at the other end of the engine so as to facilitate transverse mounting of the engine.
    Type: Grant
    Filed: March 19, 1987
    Date of Patent: December 11, 1990
    Assignee: Yamaha Hatsudoki Kabushiki Kaisha
    Inventors: Akira Hirata, Iwao Masumoto
  • Patent number: 4809647
    Abstract: An improved induction system for a V type engine that is tuned for substantially all running conditions and which is nevertheless compact in construction. The system includes a pair of plenum chambers each disposed adjacent one of the cylinder heads of the engine. Each cylinder head has at least two intake passages serving the respective cylinder bores and a first conduit extends from the adjacent plenum chamber to one of the intake passages and a second conduit extends from the other of the plenum chambers to the other intake passage. A throttle valve arrangement is also incorporated so that good performance is achieved under all running conditions. The plenum chambers communicate with each other as their opposite ends to improve airflow and a common inlet opening serves each plenum chamber inlet.
    Type: Grant
    Filed: January 13, 1987
    Date of Patent: March 7, 1989
    Assignee: Yamaha Hatsudoki Kabushiki Kaisha
    Inventors: Iwao Masumoto, Osamu Takii