Patents by Inventor Katsuo Obai

Katsuo Obai 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: 8100482
    Abstract: A brake hydraulic pressure control apparatus for a vehicle includes anti-skid control means for executing an anti-skid control including a pressure reducing control and a pressure increasing control for one of front wheels at which an anti-skid control start condition is established, yaw moment control means for executing a yaw moment control, while the anti-skid control has been executed only for a first front wheel, for a second front wheel, wheel cylinder pressure estimated value calculating means, pressure difference estimated value calculating means, pressure increasing control means, and the pressure difference estimated value calculating means including pressure difference at specific time calculating means for calculating a pressure difference estimated value at specific time on the basis of a pressure difference estimated value at the first front wheel and a wheel cylinder pressure difference between the wheel cylinder pressure estimated values at the second front wheel and the first front wheel.
    Type: Grant
    Filed: June 1, 2007
    Date of Patent: January 24, 2012
    Assignee: Advics Co., Ltd.
    Inventors: Yoshiaki Kito, Katsuo Obai, Masato Terasaka
  • Patent number: 7857399
    Abstract: An anti-skid control apparatus controls the value of electric current, which is being applied to the first solenoid valve and equal to or greater than the predetermined electric current value, to a value of electric current corresponding to the pressure difference between the master cylinder pressure and the wheel cylinder pressure at a time point where the pressure-increasing control is started; and changes the value of electric current in a direction to be reduced for a first period of time during the pressure-increasing control as the estimated amount of the wheel cylinder pressure reduced by the pressure-reducing control is increased, when the estimated amount of the wheel cylinder pressure reduced by the pressure-reducing control is equal to or greater than a predetermined value.
    Type: Grant
    Filed: June 18, 2007
    Date of Patent: December 28, 2010
    Assignee: Advics Co., Ltd.
    Inventors: Yoshiaki Kito, Katsuo Obai
  • Patent number: 7530648
    Abstract: The brake hydraulic pressure control apparatus employs, as a pressure-increasing valve, a normally-open linear solenoid valve that can linearly adjust an actual differential pressure (difference between master cylinder hydraulic pressure and a wheel cylinder hydraulic pressure). This apparatus repeatedly executes, in principle, a control cycle in which a pressure-reducing control, holding control and linear pressure-increasing control make one set, while a “linear pressure-increasing control with holding period” is executed instead of the linear pressure-increasing control only in the first-time control cycle that is started in a state where a current-value-corresponding-to-actual-differential-pressure cannot correctly be obtained.
    Type: Grant
    Filed: May 11, 2006
    Date of Patent: May 12, 2009
    Assignee: Advics Co., Ltd.
    Inventor: Katsuo Obai
  • Publication number: 20080001475
    Abstract: An anti-skid control apparatus includes: electric current controlling means for controlling the value of electric current, which is being applied to the first solenoid valve and equal to or greater than the predetermined electric current value, to a value of electric current corresponding to the pressure difference between the master cylinder pressure and the wheel cylinder pressure at a time point where the pressure-increasing control is started; and changing means for changing the value of electric current controlled by the electric current controlling means in a direction to be reduced for a first period of time during the pressure-increasing control as the estimated amount of the wheel cylinder pressure reduced by the pressure-reducing control is increased, when the estimated amount of the wheel cylinder pressure reduced by the pressure-reducing control is equal to or greater than a predetermined value.
    Type: Application
    Filed: June 18, 2007
    Publication date: January 3, 2008
    Inventors: Yoshiaki Kito, Katsuo Obai
  • Publication number: 20070290552
    Abstract: A brake hydraulic pressure control apparatus for a vehicle includes anti-skid control means for executing an anti-skid control including a pressure reducing control and a pressure increasing control for one of front wheels at which an anti-skid control start condition is established, yaw moment control means for executing a yaw moment control, while the anti-skid control has been executed only for a first front wheel, for a second front wheel, wheel cylinder pressure estimated value calculating means, pressure difference estimated value calculating means, pressure increasing control means, and the pressure difference estimated value calculating means including pressure difference at specific time calculating means for calculating a pressure difference estimated value at specific time on the basis of a pressure difference estimated value at the first front wheel and a wheel cylinder pressure difference between the wheel cylinder pressure estimated values at the second front wheel and the first front wheel.
    Type: Application
    Filed: June 1, 2007
    Publication date: December 20, 2007
    Inventors: Yoshiaki Kito, Katsuo Obai, Masato Terasaka
  • Patent number: 7216939
    Abstract: This brake hydraulic pressure control apparatus adopts, as the pressure-increasing valve, a normally-open linear solenoid valve that can linearly adjust the actual differential pressure. This apparatus repeatedly executes, in principle, a control cycle in which a pressure-reducing control, holding control and linear pressure-increasing control make one set, after ABS control start conditions are satisfied (after time t1). In this case, a pulse pressure-increasing control is executed instead of the linear pressure-increasing control only in the first-time control cycle (time t3 to t6).
    Type: Grant
    Filed: April 13, 2005
    Date of Patent: May 15, 2007
    Assignee: Advics Co., Ltd.
    Inventor: Katsuo Obai
  • Publication number: 20060255659
    Abstract: The brake hydraulic pressure control apparatus employs, as a pressure-increasing valve, a normally-open linear solenoid valve that can linearly adjust an actual differential pressure (a difference between a master cylinder hydraulic pressure Pm and a wheel cylinder hydraulic pressure Pw). This apparatus repeatedly executes, in principle, a control cycle in which a pressure-reducing control, holding control and linear pressure-increasing control make one set, while a “linear pressure-increasing control with holding period” is executed instead of the linear pressure-increasing control only in the first-time control cycle that is started in a state where a current-value-corresponding-to-actual-differential-pressure cannot correctly be obtained (the period from time t3 to time t6).
    Type: Application
    Filed: May 11, 2006
    Publication date: November 16, 2006
    Inventor: Katsuo Obai
  • Publication number: 20050225164
    Abstract: This brake hydraulic pressure control apparatus adopts, as the pressure-increasing valve, a normally-open linear solenoid valve that can linearly adjust the actual differential pressure. This apparatus repeatedly executes, in principle, a control cycle in which a pressure-reducing control, holding control and linear pressure-increasing control make one set, after ABS control start conditions are satisfied (after time t1). In this case, a pulse pressure-increasing control is executed instead of the linear pressure-increasing control only in the first-time control cycle (time t3 to t6).
    Type: Application
    Filed: April 13, 2005
    Publication date: October 13, 2005
    Inventor: Katsuo Obai