Patents by Inventor Takashi Hanaoka

Takashi Hanaoka 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: 4970997
    Abstract: A valve operating mechanism for an internal combustion engine having a valve disposed in an intake port or an exhaust port of a combustion chamber and being openable by a rotatable cam and cam follower in synchronism with the engine crankshaft rotation. The valve is normally urged toward the closed position by a spring means encircling the valve. Various embodiments are disclosed for varying the resilient force urging the valve toward the closed position during different engine operating conditions, such as, increasing the resilient valve closing force during high-speed operation for ensuring proper valve operation and decreasing the resilient valve closing force during low-speed operation for reducing friction in the valve operating mechanism. The valve operating mechanism includes means for switching between actuation by a low-speed cam or a high-speed cam. One form of the spring means includes a mechanism for increasing the spring force on the high-speed cam follower only during high-speed operation.
    Type: Grant
    Filed: February 5, 1990
    Date of Patent: November 20, 1990
    Assignee: Honda Giken Kogyo Kabushiki Kaisha
    Inventors: Kazuo Inoue, Takashi Hanaoka, Tsuneo Konno
  • Patent number: 4957076
    Abstract: A valve operating mechanism for an internal combustion engine having a valve disposed in an intake port or an exhaust port of a combustion chamber and being openable by a rotatable cam and cam follower in synchronism with the engine crankshaft rotation. The valve is normally urged toward the closed position by a spring means encircling the valve. Various embodiments are disclosed for varying the resilient force urging the valve toward the closed position during different engine operating conditions, such as, increasing the resilient valve closing force during high-speed operation for ensuring proper valve operation and decreasing the resilient valve closing force during low-speed operation for reducing friction in the valve operating mechanism. The valve operating mechanism includes means for switching between actuation by a low-speed cam or a high-speed cam. One form of the spring means includes a mechanism for increasing the spring force on the high-speed cam follower only during high-speed operation.
    Type: Grant
    Filed: February 3, 1989
    Date of Patent: September 18, 1990
    Assignee: Honda Giken Kogyo Kabushiki Kaisha
    Inventors: Kazuo Inoue, Takashi Hanaoka, Tsuneo Konno