Patents by Inventor Kazuo Aoi

Kazuo Aoi 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: 4962675
    Abstract: An improved shifting device for the hydrostatic transmission of a lawn tractor or the like. The shifting device includes means for permitting a greater latitude of movement of the shift lever without effecting either forward or reverse movement. This is done by incorporating a linkage system for interconnecting the shift lever with the transmission control that includes a lost motion connection and by providing a leak path in the hydrostatic transmission so that a greater than normal pressure must be exerted before drive in one direction is possible.
    Type: Grant
    Filed: March 17, 1989
    Date of Patent: October 16, 1990
    Assignee: Yamaha Hatsudoki Kabushiki Kaisha
    Inventors: Kazuo Aoi, Takanori Suzuki
  • Patent number: 4679532
    Abstract: A valve placement arrangement for an internal combustion engine including at least three intake valves and two exhaust valves and wherein no two of the exhaust valves are adjacent to each other and they are separated by intake valves so as to insure against undue heating and minimize thermo-loading.
    Type: Grant
    Filed: August 12, 1985
    Date of Patent: July 14, 1987
    Assignee: Yamaha Hatsudoki Kabushiki Kaisha
    Inventors: Kazuo Aoi, Naoki Tsuchida
  • Patent number: 4651696
    Abstract: A combustion chamber configuration for an engine having three intake valves and two exhaust valves per cylinder. The combustion chamber configuration permits the use of stroke-to-bore ratios of 0.8 to 1 or less and compression ratios of 9 to 1 or greater while affording good flame travel in the combustion chamber. The piston is formed with a generally flat head that has semi-circular recesses for valve clearance.
    Type: Grant
    Filed: July 17, 1985
    Date of Patent: March 24, 1987
    Assignee: Yamaha Hatsudoki Kabushiki Kaisha
    Inventors: Masaaki Yoshikawa, Kazuo Aoi
  • Patent number: 4638774
    Abstract: A valve actuating mechanism for an internal combustion engine that permits the use of a plurality of valves per combustion chamber. There are a greater number of intake valves than exhaust valves and the intake valves are actuated by means of a single rocker arm associated with a first cam shaft. The exhaust valves are individually and directly operated by a second camshaft.
    Type: Grant
    Filed: June 11, 1985
    Date of Patent: January 27, 1987
    Assignee: Yamaha Hatsudoki Kabushiki Kaisha
    Inventor: Kazuo Aoi
  • Patent number: 4617881
    Abstract: Two embodiments of valve arrangements for internal combustion engines that permits the use of a plurality of valves for a given combustion chamber while operating all of the valves through a simplified camshaft arrangement. Some of the valves are operated directly by the cam lobes and others are operated by rocker arms. In addition, an embodiment is disclosed wherein a two rocker arm arrangement is employed for operating certain valves.
    Type: Grant
    Filed: March 29, 1985
    Date of Patent: October 21, 1986
    Assignee: Yamaha Hatsudoki Kabushiki Kaisha
    Inventors: Kazuo Aoi, Naoki Tsuchida
  • Patent number: 4593657
    Abstract: An internal combustion engine of the multiple valve type embodying an improved supporting arrangement for a camshaft that directly operates one valve and indirectly operates a pair of valves. The camshaft is provided with bearing surfaces on opposite sides of the cam lobes and a pair of bearing caps cooperate with the cylinder head for supporting these bearing surfaces. Each bearing cap and the cylinder head journal one of the bearing surfaces of the camshaft around its circumference and the other of the camshaft bearing surfaces are journaled only by the bearing cap and not by the cylinder head so as to afford clearance and yet adequate support.
    Type: Grant
    Filed: June 11, 1985
    Date of Patent: June 10, 1986
    Assignee: Yamaha Hatsudoki Kabushiki Kaisha
    Inventors: Kazuo Aoi, Toshikazu Ozawa