Patents Assigned to Japan Automatic Transmission Co., Ltd.
  • Patent number: 5154100
    Abstract: An automatic power transmission control system includes a solenoid valve which is associated with an electric or electronic controller to receive therefrom a control signal. The solenoid valve generates a hydraulic control pressure in response to the control signal. The solenoid valve supplies the control pressure to a shift valve for switching shift valve position between a higher gear position and a lower gear position. The solenoid valve is also hydraulically communicated with a hydraulic device which performs desired operations associated with gear position shifting operation. The solenoid valve supplies the control pressure to the hydraulic device for controlling operation of the latter corresponding to the selected gear position.
    Type: Grant
    Filed: July 15, 1991
    Date of Patent: October 13, 1992
    Assignee: Japan Automatic Transmission Co., Ltd.
    Inventors: Toshiharu Yamada, Kenichi Sakamoto, Hiroki Suzuki
  • Patent number: 4942530
    Abstract: An automatic transmission including a torque converter and a multiple stage transmission gear mechanism. A hydraulically actuated brake and a hydraulically actuated clutch is provided for alternate engagement to select alternately one of two adjacent gear stages. In order to prevent gear shift shock, the engaging of the clutch or the brake is controlled so that the engaging rate is faster for a predetermined time period in an initial period of a gear shifting operation than in a remainder period. A control circuit is provided to monitor the gear shifting operation and modifying the predetermined time period in accordance with the results of the latest gear shifting operation and store the modified value for the use in a next gear shifting operation.
    Type: Grant
    Filed: March 1, 1988
    Date of Patent: July 17, 1990
    Assignees: Mazda Motor Corporation, Japan Automatic Transmission Co., Ltd.
    Inventors: Keiji Boda, Kouichirou Waki, Kazuo Niide, Hiroaki Yokota, Keizo Yanagisawa, Hokuto Takeuchi
  • Patent number: 4914594
    Abstract: A selector position detector arrangement for an automotive automatic transmission includes a detector producing a level signal variable of the level depending upon the selector level position. The level signal is converted into digital signal having a value corresponding to the level of the level signal. The digital signal value is compared with present reference values corresponding to the transmission selector positions.
    Type: Grant
    Filed: February 11, 1988
    Date of Patent: April 3, 1990
    Assignee: Japan Automatic Transmission Co., Ltd.
    Inventor: Kunihiko Sano
  • Patent number: 4881429
    Abstract: In order to obviate a knocking noise in a one-way clutch during upshifting under low engine load, a hydraulically controlled clutch, which is arranged in parallel therewith, is momentary supplied with line pressure.
    Type: Grant
    Filed: April 29, 1988
    Date of Patent: November 21, 1989
    Assignees: Nissan Motor Co., Ltd., Japan Automatic Transmission Co., Ltd.
    Inventors: Masayuki Kobayashi, Masahiro Takiguchi
  • Patent number: 4709596
    Abstract: A vehicle automatic transmission having a torque converter and a multiple stage transmission gear mechanism connected with the torque converter. The gear stage of the gear mechanism is selected in accordance with the vehicle operating condition. The transmission includes friction members. One of the friction members is engaged for a higher gear stage and disengaged for a lower gear stage whereas the other is disengaged for the higher gear stage and engaged for the lower gear stage. In shifting down from the higher gear stage to the lower gear stage, the other friction member is engaged after a predetermined time from the disengagement of the one friction member.
    Type: Grant
    Filed: October 30, 1986
    Date of Patent: December 1, 1987
    Assignees: Mazda Motor Corporation, Japan Automatic Transmission Co., Ltd.
    Inventors: Keiji Boda, Kouichirou Waki, Keizo Yanagisawa