Patents by Inventor Youichi Hatakawa

Youichi Hatakawa 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).

  • Hydraulic control device for an automatic transmission
    Patent number: 5092201
    Abstract: A check valve and an orifice are situated in a feeder oil passage to an accumulator so that influence of drained oil from the accumulator is eliminated when a hydraulic servo is drained. The hydraulic pressure is supplied to the servo through the orifice, and to the accumulator with the feeder oil passage separate from the oil passage to the hydraulic servo with the check valve being opened. When draining, the hydraulic pressure in the hydraulic servo is drained quickly, however, the hydraulic pressure in the accumulator is drained gradually because the check valve is closed.
    Type: Grant
    Filed: September 12, 1990
    Date of Patent: March 3, 1992
    Assignee: Aisin Aw Co., Ltd.
    Inventors: Youichi Hatakawa, Yoshinari Kuwayama, Yoshihiro Yamada