Patents by Inventor Masayasu Ohkubo

Masayasu Ohkubo 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).

  • Publication number: 20150091370
    Abstract: A brake ECU brings master cut valves into an open state and brings holding valves into a closed state, thereby controlling a master cylinder and wheel cylinders to communicate to each other when a magnitude of a hydraulic pressure detected by an accumulator pressure sensor has decreased to a value less than a predetermined value set in advance. On the other hand, the ECU maintains holding valves in an open state, and controls an accumulator and the wheel cylinders to communicate to each other via linear control valves. Then, the ECU determines in which brake system a failure occurs out of a brake system for a front right wheel, a brake system for a front left wheel, and brake systems for rear right and left wheels based on changes in hydraulic pressure detected by a sensor, a master cylinder pressure sensor, and a control pressure sensor.
    Type: Application
    Filed: April 5, 2012
    Publication date: April 2, 2015
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Tsuyoshi Yamasaki, Masayasu Ohkubo
  • Publication number: 20150091369
    Abstract: A brake ECU uses a control pressure acquired from a control pressure sensor to determine whether a valve closing operation abnormality or a valve opening operation abnormality occurs in one of a pressure increasing linear control valve and an adjusted flow rate cut valve in a state where a hydraulic pressure is supplied from an accumulator. The brake ECU controls, if the brake ECU determines that an abnormality occurs, respectively the control valve and the cut valve to change to an open state or a closed state, and identifies, based on a change in the control pressure acquired from the control pressure sensor, in which of the control valve and the cut valve the valve opening operation abnormality or the valve closing operation abnormality occurs. The brake ECU can use, after a valve in which the valve opening operation abnormality or the valve closing operation abnormality occurs is identified, a valve in which the abnormality does not occur to carry out brake control.
    Type: Application
    Filed: April 5, 2012
    Publication date: April 2, 2015
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Tsuyoshi Yamasaki, Masayasu Ohkubo
  • Patent number: 8870301
    Abstract: A hydraulic brake system includes: a hydraulic pressure source provided for a vehicle, and including a hydraulic-pressure generating device and a reservoir; a plurality of hydraulic brakes provided for respective wheels of the vehicle, and configured to restrain rotations of the respective wheels; and a control valve device including at least one hydraulic-pressure control valve group disposed between the hydraulic-pressure generating device and at least one of brake cylinders of the hydraulic brakes and/or between the reservoir and the at least one of the brake cylinders. Each of the at least one hydraulic-pressure control valve group includes (a) at least one ON/OFF control valve and (b) at least one linear control valve that are disposed in parallel with each other.
    Type: Grant
    Filed: September 17, 2010
    Date of Patent: October 28, 2014
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Masayasu Ohkubo, Yoshito Tanaka, Hiroshi Nakaoka, Takayuki Yamamoto, Tetsuya Miyazaki
  • Publication number: 20130207451
    Abstract: A hydraulic brake system includes: a hydraulic pressure source provided for a vehicle, and including a hydraulic-pressure generating device and a reservoir; a plurality of hydraulic brakes provided for respective wheels of the vehicle, and configured to restrain rotations of the respective wheels; and a control valve device including at least one hydraulic-pressure control valve group disposed between the hydraulic-pressure generating device and at least one of brake cylinders of the hydraulic brakes and/or between the reservoir and the at least one of the brake cylinders. Each of the at least one hydraulic-pressure control valve group includes (a) at least one ON/OFF control valve and (b) at least one linear control valve that are disposed in parallel with each other.
    Type: Application
    Filed: September 17, 2010
    Publication date: August 15, 2013
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Masayasu Ohkubo, Yoshito Tanaka, Hiroshi Nakaoka, Takayuki Yamamoto, Tetsuya Miyazaki
  • Publication number: 20130153801
    Abstract: An electromagnetic linear valve includes a housing including a core closing an opening at one end portion of the body portion, and a separation portion separating an interior into a first liquid chamber located in a core side and a second liquid chamber; a plunger disposed in the first liquid chamber so as to move along the axis in a state in which one end thereof faces to the core and the other end can sit on a hole; an elastic member applying a force to move the plunger away from the core; and a coil generating magnetic field to move the plunger toward the core. A recess is formed in a section of an inner circumferential portion of the body portion which intersects with an end face of the core in the first direction.
    Type: Application
    Filed: September 6, 2010
    Publication date: June 20, 2013
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Kei Sato, Masaki Nanahara, Masayasu Ohkubo
  • Patent number: 8007056
    Abstract: A brake control apparatus has first and second wheel cylinders; a master cylinder unit; first and second systems; a separation valve; a pressure control mechanism that controls the working fluid pressure transferred to at least one of the first and second wheel cylinders independently of the brake operation, and a brake ECU. The brake ECU generates a differential pressure across the separation valve by operating the pressure control mechanism when there is no brake operation while a running drive source of a vehicle is stopped to determine whether the separation valve has a leakage abnormality.
    Type: Grant
    Filed: October 4, 2006
    Date of Patent: August 30, 2011
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Masayasu Ohkubo, Akihiro Otomo, Tsukasa Fukasawa
  • Patent number: 7926887
    Abstract: A brake control system includes at least one wheel cylinder that receives the work fluid to apply a braking force to a corresponding vehicle wheel, a wheel cylinder pressure control system that controls the control pressure applied to the at least one wheel cylinder by controlling the supply of the work fluid thereto, a first abnormality determination unit that determines whether an abnormality in the wheel cylinder pressure control system based on an initial response characteristic of the control pressure after a braking request within a predetermined abnormality determination time, and a second abnormality determination unit that determines whether the abnormality in the wheel cylinder pressure system is present based on a comparison between the control pressure and a reference pressure based on which the determination is made with respect to the abnormality within a predetermined second abnormality determination time that is set to expire before expiration of the first abnormality determination time.
    Type: Grant
    Filed: October 2, 2006
    Date of Patent: April 19, 2011
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventor: Masayasu Ohkubo
  • Patent number: 7708354
    Abstract: The invention provides a brake control apparatus that improves the controllability of a vehicle in the control for restraining slip of the wheels. The brake control apparatus includes: wheel cylinders that apply braking force individually to wheels by supplying a working fluid; retention valves that are provided respectively upstream of the wheel cylinders and that are opened and closed so as to restrain slip of the wheels; a common control valve provided upstream of the retention valves to supply the working fluid to the wheel cylinders; and a control portion that controls the common control valve by different control laws to restrain fluctuations in pressure on a primary side of the retention valves caused by fluctuations in a capacity to which the working fluid from the common control valve is supplied, by opening or closing of the retention valves.
    Type: Grant
    Filed: October 25, 2006
    Date of Patent: May 4, 2010
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Masayasu Ohkubo, Yasuji Mizutani, Kazuyoshi Sakazaki
  • Patent number: 7588298
    Abstract: A non-consideration creating portion creates a non-consideration control command value based on a target value and an actual value of hydraulic pressure of a brake cylinder in a control-target brake system i. A consideration creating portion creates a consideration control command value based on the target value and the actual value of the hydraulic pressure in the control-target brake system i and a target value and an actual value of hydraulic pressure in a comparison-target brake system j. Then, one of the consideration control command value and the non-consideration command value is selected based on an absolute value of a difference in the target value between the control-target brake system i and the comparison-target brake system j, and a combination of a control mode in the control-target brake system i and a control mode in the comparison-target brake system j.
    Type: Grant
    Filed: November 21, 2008
    Date of Patent: September 15, 2009
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Hiroshi Nakaoka, Yoshito Tanaka, Masayasu Ohkubo, Masaaki Komazawa
  • Publication number: 20090096284
    Abstract: A non-consideration creating portion creates a non-consideration control command value based on a target value and an actual value of hydraulic pressure of a brake cylinder in a control-target brake system i. A consideration creating portion creates a consideration control command value based on the target value and the actual value of the hydraulic pressure in the control-target brake system i and a target value and an actual value of hydraulic pressure in a comparison-target brake system j. Then, one of the consideration control command value and the non-consideration command value is selected based on an absolute value of a difference in the target value between the control-target brake system i and the comparison-target brake system j, and a combination of a control mode in the control-target brake system i and a control mode in the comparison-target brake system j.
    Type: Application
    Filed: November 21, 2008
    Publication date: April 16, 2009
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Hiroshi Nakaoka, Yoshito Tanaka, Masayasu Ohkubo, Masaaki Komazawa
  • Patent number: 7513578
    Abstract: A non-consideration creating portion creates a non-consideration control command value based on a target value and an actual value of hydraulic pressure of a brake cylinder in a control-target brake system i. A consideration creating portion creates a consideration control command value based on the target value and the actual value of the hydraulic pressure in the control-target brake system i and a target value and an actual value of hydraulic pressure in a comparison-target brake system j. Then, one of the consideration control command value and the non-consideration command value is selected based on an absolute value of a difference in the target value between the control-target brake system i and the comparison-target brake system j, and a combination of a control mode in the control-target brake system i and a control mode in the comparison-target brake system j.
    Type: Grant
    Filed: October 18, 2005
    Date of Patent: April 7, 2009
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Hiroshi Nakaoka, Yoshito Tanaka, Masayasu Ohkubo, Masaaki Komazawa
  • Publication number: 20070114842
    Abstract: The invention provides a brake control apparatus that improves the controllability of a vehicle in the control for restraining slip of the wheels. The brake control apparatus includes: wheel cylinders that apply braking force individually to wheels by supplying a working fluid; retention valves that are provided respectively upstream of the wheel cylinders and that are opened and closed so as to restrain slip of the wheels; a common control valve provided upstream of the retention valves to supply the working fluid to the wheel cylinders; and a control portion that controls the common control valve by different control laws to restrain fluctuations in pressure on a primary side of the retention valves caused by fluctuations in a capacity to which the working fluid from the common control valve is supplied, by opening or closing of the retention valves.
    Type: Application
    Filed: October 25, 2006
    Publication date: May 24, 2007
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Masayasu Ohkubo, Yasuji Mizutani, Kazuyoshi Sakazaki
  • Publication number: 20070108837
    Abstract: A brake control apparatus has first and second wheel cylinders; a master cylinder unit; first and second systems; a separation valve; a pressure control mechanism that controls the working fluid pressure transferred to at least one of the first and second wheel cylinders independently of the brake operation, and a brake ECU. The brake ECU generates a differential pressure across the separation valve by operating the pressure control mechanism when there is no brake operation while a running drive source of a vehicle is stopped to determine whether the separation valve has a leakage abnormality.
    Type: Application
    Filed: October 4, 2006
    Publication date: May 17, 2007
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Masayasu Ohkubo, Akihiro Otomo, Tsukasa Fukasawa
  • Publication number: 20070090690
    Abstract: A brake control system includes at least one wheel cylinder that receives the work fluid to apply a braking force to a corresponding vehicle wheel, a wheel cylinder pressure control system that controls the control pressure applied to the at least one wheel cylinder by controlling the supply of the work fluid thereto, a first abnormality determination unit that determines whether an abnormality in the wheel cylinder pressure control system based on an initial response characteristic of the control pressure after a braking request within a predetermined abnormality determination time, and a second abnormality determination unit that determines whether the abnormality in the wheel cylinder pressure system is present based on a comparison between the control pressure and a reference pressure based on which the determination is made with respect to the abnormality within a predetermined second abnormality determination time that is set to expire before expiration of the first abnormality determination time.
    Type: Application
    Filed: October 2, 2006
    Publication date: April 26, 2007
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventor: Masayasu Ohkubo
  • Publication number: 20060158033
    Abstract: A brake fluid pressure control apparatus of a vehicle includes a hydraulic brake in which the fluid pressure of a brake cylinder for a wheel is controlled so as to retard the rotation of the wheel, and a hydraulic actuator capable of controlling the fluid pressure of the brake cylinder. An actuator controller feedback-controls the hydraulic actuator so that the actual fluid pressure of the brake cylinder approaches a target fluid pressure determined in accordance with a braking requirement. The actuator controller determines a control gain used when determining a control command value to be sent to the hydraulic actuator, based on at least one of the temperature of a working fluid and a slipping state of the wheel.
    Type: Application
    Filed: December 29, 2005
    Publication date: July 20, 2006
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Masayasu Ohkubo, Yoshito Tanaka, Hiroshi Nakaoka, Masaaki Komazawa
  • Publication number: 20060087175
    Abstract: A non-consideration creating portion creates a non-consideration control command value based on a target value and an actual value of hydraulic pressure of a brake cylinder in a control-target brake system i. A consideration creating portion creates a consideration control command value based on the target value and the actual value of the hydraulic pressure in the control-target brake system i and a target value and an actual value of hydraulic pressure in a comparison-target brake system j. Then, one of the consideration control command value and the non-consideration command value is selected based on an absolute value of a difference in the target value between the control-target brake system i and the comparison-target brake system j, and a combination of a control mode in the control-target brake system i and a control mode in the comparison-target brake system j.
    Type: Application
    Filed: October 18, 2005
    Publication date: April 27, 2006
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Hiroshi Nakaoka, Yoshito Tanaka, Masayasu Ohkubo, Masaaki Komazawa
  • Patent number: 6913326
    Abstract: Hydraulic pressure control apparatus for controlling a pressure of a brake cylinder pressure, including a pump device connected to the brake cylinder and including at least one set of a pump for delivering a pressurized fluid to the brake cylinder and a pump operating electric motor, a low-pressure source for storing the fluid discharged from the brake cylinder, a solenoid-operated pressure control valve disposed between the low-pressure source and the brake cylinder and operated with an electric energy applied thereto, for controlling the brake cylinder pressure depending upon the electric energy, and a controller including a pressure increase control device for increasing the brake cylinder pressure by controlling the electric motor, and a pressure reduction control device or reducing the brake cylinder pressure by controlling the electric energy applied to the control valve.
    Type: Grant
    Filed: August 19, 1999
    Date of Patent: July 5, 2005
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Masayasu Ohkubo, Kiyoharu Nakamura, Akira Sakai, Shinichi Soejima, Amane Shimura
  • Patent number: 6450591
    Abstract: In a hydraulic brake pressure control system, a master cylinder generates a brake fluid pressure proportional to a brake pedal pressure and a high-pressure supply device generates an increased brake fluid pressure. A hydraulic circuit having a wheel cylinder device is capable of performing a master cylinder control to control a wheel cylinder pressure by using the pressure generated by the master cylinder, and capable of performing a brake-by-wire control to control the wheel cylinder pressure by using the pressure generated by the high-pressure supply device. The hydraulic brake pressure control system includes a master cut valve device which controls a flow of brake fluid from the master cylinder into the wheel cylinder device. A wheel cylinder sensor device outputs a signal indicative of the brake fluid pressure in the wheel cylinder device.
    Type: Grant
    Filed: August 3, 1998
    Date of Patent: September 17, 2002
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Fumiaki Kawahata, Masayasu Ohkubo
  • Patent number: 6126248
    Abstract: In a hydraulic brake device, a pressurizing chamber receives a master cylinder pressure generated by a master cylinder. A pressure adjusting chamber receives an accumulator pressure generated by a high pressure source. A booster piston is movably provided between the pressurizing chamber and the pressure adjusting chamber. The booster piston is actuated in a first direction away from the pressurizing chamber by a pressure in the pressurizing chamber and actuated in a direction opposite to the first direction by a pressure in the pressure adjusting chamber. A flow control mechanism responsive to a movement of the booster piston is provided. The flow control mechanism makes the pressure adjusting chamber open to the high pressure source when the booster piston is moved in the first direction exceeding a predetermined distance, and closes the pressure adjusting chamber to be cut off from the high pressure source when the booster piston is moved in the opposite direction back to an initial position.
    Type: Grant
    Filed: July 27, 1998
    Date of Patent: October 3, 2000
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Fumiaki Kawahata, Masayasu Ohkubo
  • Patent number: 5992949
    Abstract: A hydraulic brake control apparatus in which a master cylinder supplies a brake fluid pressure responsive to a brake operating force to wheel cylinders through a first valve, includes a first control unit which controls second valves and third valves when a brake fluid pressure supplied to the wheel cylinders by a pressure supplying device is detected to be excessively high under a condition in which the supply of the brake fluid pressure to the wheel cylinders by the master cylinder is inhibited by the first valve, so that the supply of the brake fluid pressure to the wheel cylinders by the pressure supplying device is inhibited by the second valves and a flow of the brake fluid from the wheel cylinders into a reservoir tank is allowed by the third valves.
    Type: Grant
    Filed: July 1, 1997
    Date of Patent: November 30, 1999
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Kiyoharu Nakamura, Fumiaki Kawahata, Masayasu Ohkubo, Hirohiko Morikawa, Akira Sakai, Akihiro Ohtomo