Patents by Inventor Katsuyuki Tanahashi

Katsuyuki Tanahashi 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: 7033297
    Abstract: A shift control apparatus for controlling shifting actions of an automatic transmission including a hydraulically operated frictional coupling device having a hydraulic cylinder which is supplied with a working fluid when the frictional coupling device is engaged, the shift control apparatus including a transient-hydraulic-pressure control device operable to control a transient value of a hydraulic pressure in the hydraulic cylinder according to an electric signal, upon releasing of the frictional coupling device, and an accumulator having a back-pressure chamber a back pressure of which is controllable, and an accumulator chamber connected to the hydraulic cylinder of the frictional coupling device and operable to control a transient value of the hydraulic pressure in the hydraulic cylinder, when the frictional coupling device is engaged with the working fluid being supplied to the hydraulic cylinder, and a back-pressure increasing portion operable to increase the back pressure in the back-pressure chamber o
    Type: Grant
    Filed: May 14, 2004
    Date of Patent: April 25, 2006
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Yoshinobu Nozaki, Hideo Tomomatsu, Katsuyuki Tanahashi
  • Publication number: 20040242361
    Abstract: A shift control apparatus for controlling shifting actions of an automatic transmission including a hydraulically operated frictional coupling device having a hydraulic cylinder which is supplied with a working fluid when the frictional coupling device is engaged, the shift control apparatus including a transient-hydraulic-pressure control device operable to control a transient value of a hydraulic pressure in the hydraulic cylinder according to an electric signal, upon releasing of the frictional coupling device, and an accumulator having a back-pressure chamber a back pressure of which is controllable, and an accumulator chamber connected to the hydraulic cylinder of the frictional coupling device and operable to control a transient value of the hydraulic pressure in the hydraulic cylinder, when the frictional coupling device is engaged with the working fluid being supplied to the hydraulic cylinder, and a back-pressure increasing portion operable to increase the back pressure in the back-pressure chamber o
    Type: Application
    Filed: May 14, 2004
    Publication date: December 2, 2004
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Yoshinobu Nozaki, Hideo Tomomatsu, Katsuyuki Tanahashi
  • Patent number: 5881858
    Abstract: A hydraulic servo-mechanism for an automatic transmission, including a hydraulic servo for applying a band brake to engage a band to a drum. The hydraulic servo includes a rod which is selectively positionable to an apply position for applying the band brake, a standby position in which the rod is retracted by a predetermined extent in a release direction from the apply position, and a retracted position in which the rod is further retracted in the release direction from the standby position to release the band brake.
    Type: Grant
    Filed: December 27, 1996
    Date of Patent: March 16, 1999
    Assignee: Aisin AW Co., Ltd.
    Inventors: Kazumasa Tsukamoto, Masahiro Hayabuchi, Masaaki Nishida, Akitoshi Kato, Katsuyuki Tanahashi
  • Patent number: 5749802
    Abstract: An automatic transmission control apparatus has first and second hydraulic servos for engaging forward and reverse driving friction engaging elements, respectively, a fluid pressure control unit, a range shift detector, and an electronic control unit. When the forward driving range is selected, the fluid pressure control unit supplies a forward driving range pressure to the hydraulic servo via a changeover valve operated by a signal pressure from a normal open-type solenoid valve, when the signal pressure is drained. When the reverse driving range is selected, the electronic control unit outputs a signal to magnetize the solenoid valve. The solenoid valve is thus turned on to discontinue the drain. The control apparatus thus prevents low pressure in the reverse driving range pressure to prevent delay of engagement of the clutch.
    Type: Grant
    Filed: May 8, 1996
    Date of Patent: May 12, 1998
    Assignee: Aisin AW Co., Ltd.
    Inventors: Katsuyuki Tanahashi, Hiroshi Tsutsui, Yoshihisa Yamamoto, Kazumasa Tsukamoto
  • Patent number: 5707316
    Abstract: An automatic transmission control apparatus has a clutch, a hydraulic servo for the clutch, a fluid pressure control unit, a range shift detector, and an electronic control unit. The fluid pressure control unit has a manual valve, a pressure regulating valve device, and a changeover valve device. The electronic control unit controls the changeover valve device and the pressure regulating valve device. Immediately after a shift to the forward driving range, the electronic control unit holds the changeover valve device in such a state that a forward driving range pressure is supplied without passing through the pressure regulating valve device. Then, the electronic control unit shifts the changeover valve device to such a state that a regulated pressure is supplied from the pressure regulating valve device, which has been switched to a pressure regulating state by the electronic control unit. This control operation precisely sets the fluid pressure changeover timing and the initial fluid pressure.
    Type: Grant
    Filed: May 8, 1996
    Date of Patent: January 13, 1998
    Assignee: Aisin AW Co., Ltd.
    Inventors: Katsuyuki Tanahashi, Yoshihisa Yamamoto, Hiroshi Tsutsui