Patents by Inventor Kunihiro Matsunaga

Kunihiro Matsunaga 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: 5472268
    Abstract: The present invention relates to a brake fluid pressure control apparatus provided with a flow valve which, during the normal operation, when a spool is in the stationary position, a master cylinder communication port is communicated with a wheel cylinder communication port while the pump communication port is closed, and during an antiskid control operation, a pump communication port and a wheel cylinder communication port are communicated, as well as a switching device to switch between the first and the second conditions. In the first condition, a master cylinder communication port is communicated with the output fluid passage of the master cylinder while the communication between the pump communication port and the master cylinder communication port is shut off.
    Type: Grant
    Filed: October 7, 1993
    Date of Patent: December 5, 1995
    Assignee: Tokico Ltd.
    Inventors: Hiromi Ando, Kunihiro Matsunaga
  • Patent number: 5397175
    Abstract: The present invention presents an economical fluid pressure control device particularly applicable to controlling the fluid pressure in the wheels of an automobile provided with an antiskid capability so that the unpleasant pedal kickbacks are prevented under various operating conditions of the wheels. This is achieved by providing at least two wheel cylinders for one pressure generation source, a reservoir and a pump. A flow valve provided on each of the wheel cylinders is provided with a simple flow switching device which control the position of a spool, disposed inside the flow valve, which assumes a stationary position for non-antiskid operation mode and a operation position for antiskid operation mode. When one of the wheels is in the antiskid operation mode, and the other wheel is in non-antiskid operation mode, the brake fluid discharged from the pump is not allowed to enter the flow valve disposed in the non-antiskid operation mode.
    Type: Grant
    Filed: February 16, 1993
    Date of Patent: March 14, 1995
    Assignee: Tokico Ltd.
    Inventors: Kunihiro Matsunaga, Toshio Takayama, Hiromi Ando
  • Patent number: 5335982
    Abstract: The present invention relates to a brake fluid pressure control apparatus in which a casing contains a pump communication port separately from a master cylinder communication port. A spool is also provided which limits the communication between the pump communication port and the master cylinder communication port in a manner such that the discharge pressure from the pump is not added directly to the master cylinder. Additionally, in the intake and discharge sides of the pump, a bypass channel is provided. In this bypass channel, a relief valve is provided which allows the escape of pressure force to the intake side of the pump in the case when the pressure force between the discharge side of the pump and the flow control valve increases to a high pressure.
    Type: Grant
    Filed: March 31, 1993
    Date of Patent: August 9, 1994
    Assignee: Tokico Ltd.
    Inventors: Hiromi Ando, Kunihiro Matsunaga, Kenji Sano, Satoru Suga
  • Patent number: 5312175
    Abstract: The present invention relates to a brake fluid pressure control apparatus in which a casing contains a pump communication port separately from a master cylinder communication port. A spool is also provided which limits the communication between the pump communication port and the master cylinder communication port in a manner such that the discharge pressure from the pump is not added directly to the master cylinder. Additionally, in the intake and discharge sides of the pump, a bypass channel is provided. In this bypass channel, a relief valve is provided which allows the escape of pressure force to the intake side of the pump in the case when the pressure force between the discharge side of the pump and the flow control increases to a high pressure.
    Type: Grant
    Filed: June 26, 1992
    Date of Patent: May 17, 1994
    Assignee: Tokico Ltd.
    Inventors: Hiromi Ando, Kunihiro Matsunaga, Kenji Sano, Satoru Suga
  • Patent number: 5080446
    Abstract: A hydraulic pressure control device of a load sensing type is provided. The hydraulic pressure control device includes a spring support disposed on a vehicle body side or wheel side for supporting a suspension spring, a support member tiltably disposed in the spring support for supporting a load of the suspension spring at three support portions, and a hydraulic pressure control valve mounted on the support member for controlling hydraulic pressure supplied to a braking unit mounted on a wheel from a source for generating hydraulic braking pressure. Thus, at least a portion of the force applied to one of the support portions can be applied to a control piston of the hydraulic pressure control valve.
    Type: Grant
    Filed: September 11, 1990
    Date of Patent: January 14, 1992
    Assignee: Tokico Ltd.
    Inventor: Kunihiro Matsunaga
  • Patent number: 4736823
    Abstract: An anti-skid device for use in a vehicle hydraulic brake system comprising a hydraulic pressure generating device for generating hydraulic pressure in response to actuation of a brake pedal, a brake cylinder for receiving the hydraulic pressure from the hydraulic pressure generating device and for applying brake force to a wheel of the vehicle, a passage through which the hydraulic pressure is adapted to be transmitted from the hydraulic pressure generating device to the brake cylinder, lock detecting device for detecting that a wheel is locked and a damping valve designed to function to interrupt the transmission of the hydraulic pressure from the hydraulic pressure generating device to the brake cylinder and to further reduce the pressure in the brake cylinder when the lock detecting mechanism detects that wheel is locked so that the wheel-lock may be released.
    Type: Grant
    Filed: March 19, 1987
    Date of Patent: April 12, 1988
    Assignee: Tokico Ltd.
    Inventors: Hiromi Ando, Kunihiro Matsunaga