Patents by Inventor Tatsuo Niiyama

Tatsuo Niiyama 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: 5860402
    Abstract: An improved compact oil pump drive arrangement for an internal combustion engine having an auxiliary shaft that is driven by the crankshaft. The oil pump is driven by an oil pump drive shaft that is disposed between the auxiliary shaft and the crankshaft by a helical gear arrangement. The auxiliary drive shaft is also driven by a helical gear arrangement, and the helical gears on the auxiliary drive shaft are of appropriate hands so as to balance the axial thrusts on the auxiliary drive shaft.
    Type: Grant
    Filed: July 19, 1996
    Date of Patent: January 19, 1999
    Assignee: Yamaha Hatsudoki Kabushiki Kaisha
    Inventors: Kenichi Sakurai, Tatsuo Niiyama, Masahiro Uchida
  • Patent number: 5740768
    Abstract: A two-stage cam shaft drive arrangement for an internal combustion engine employing a pair of flexible transmitters. The two-stage mechanism is driven by an intermediate shaft that is driven off of the crankshaft at a point between its ends. Flexible transmitter tensioners are engaged with the flexible transmitters on the side away from the cylinder block for ease of accessibility and to maintain a more compact engine configuration.
    Type: Grant
    Filed: July 19, 1996
    Date of Patent: April 21, 1998
    Assignee: Yamaha Hatsudoki Kubushiki Kaisha
    Inventors: Kenichi Sakurai, Tatsuo Niiyama, Masahiro Uchida
  • Patent number: 5724930
    Abstract: A compact arrangement for an inline multiple-cylinder engine for driving a pair of twin overhead camshafts. The camshafts are driven by a drive that includes an intermediate shaft and at least a portion of the drive and the intermediate shaft is accessible through one or more openings formed in the side of the engine body. A manifold is also provided on this side of the engine and is configured so that it does not substantially obstruct the openings.
    Type: Grant
    Filed: October 21, 1996
    Date of Patent: March 10, 1998
    Assignee: Yamaha Hatsudoki Kabushiki Kaisha
    Inventors: Kenichi Sakurai, Tatsuo Niiyama, Masahiro Uchida
  • Patent number: 5231961
    Abstract: An improved camshaft and accessory drive arrangement for a V type engine wherein pairs of overhead cams are driven from the crankshaft by means of intermediate shafts that are directly driven by the crankshaft. The axis of rotation of the intermediate shafts is disposed closer to the axis of rotation of the crankshaft than the axes of rotation of the camshafts. An accessory is positioned in the valley of the V and is also driven by the crankshaft but is spaced further from the crankshaft axis of rotation than the intermediate shafts. This accessory is a water pump and an oil pump is also driven by the crankshaft at the same end of the engine.
    Type: Grant
    Filed: January 19, 1990
    Date of Patent: August 3, 1993
    Assignee: Yamaha Hatsudoki Kabushiki Kaisha
    Inventors: Kazuo Shimada, Tatsuo Niiyama, Tetsushi Saito
  • Patent number: 5033421
    Abstract: A camshaft drive arrangement for a V type engine having a pair of flexible transmitters that drive intermediate shafts which, in turn, drive respective camshafts associated with the respective cylinder banks. A combined flexible transmitter and guide member is disposed between the flexible transmitters that drive the intermediate shafts for tensioning one of these flexible transmitters and acting as a guide for the other of them.
    Type: Grant
    Filed: February 14, 1990
    Date of Patent: July 23, 1991
    Assignee: Yamaha Hatsudoki Kabushiki Kaisha
    Inventors: Kazuo Shimada, Tatsuo Niiyama, Minoru Yonezawa