Patents by Inventor Hideaki Ohtubo

Hideaki Ohtubo 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).

  • Speed stage shifting of automatic transmission by reduction of servo oil pressure to slip limit stand-by pressure and subsequent decrements
    Patent number: 5363724
    Abstract: In a certain speed stage shifting of an automatic transmission of a vehicle including a speed change gear mechanism including rotary members such as gears and gear carriers and hydraulically operated friction engaging brakes and clutches adapted to provide various speed stages according to selective engagement and disengagement of the friction engaging brakes and clutches, the servo oil pressure of a first friction engaging brake is immediately lowered down to a stand-by pressure marginally higher than a threshold pressure bordering non sliding and sliding of the first friction engaging brake at the start of a change-over of a second friction engaging brake is and then, when a substantial change-over of the second friction engaging means started, the servo oil pressure is further lowered across the threshold pressure and thereafter periodically lowered by a decrement the magnitude of which may desirably be increased along with a lapse of time.
    Type: Grant
    Filed: September 29, 1992
    Date of Patent: November 15, 1994
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Norimi Asahara, Yasuo Hojo, Hideaki Ohtubo