Patents by Inventor Toshiya Oosawa

Toshiya Oosawa 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: 20190184958
    Abstract: There are provided a brake device that enhances the detection accuracy of a system with fluid leakage, regardless of the degree of fluid leakage, and a fluid leakage detection method of the brake device. The brake device includes a hydraulic unit and a control unit.
    Type: Application
    Filed: June 16, 2017
    Publication date: June 20, 2019
    Applicant: Hitachi Automotive Systems, Ltd.
    Inventors: Asahi WATANABE, Toshiya OOSAWA
  • Patent number: 10252707
    Abstract: A system comprises: pump (hydraulic pressure source) that uses brake fluid supplied from reservoir tank (reservoir) to generate hydraulic pressure in first hydraulic line, thereby generating hydraulic pressure in wheel cylinder; piston configured to move axially in cylinder under the action of hydraulic fluid supplied from master cylinder, piston dividing cylinder into at least two chambers (positive pressure chamber and backpressure chamber); stroke simulator for generating reaction force to a driver's brake operation by moving piston; second hydraulic line provided between positive pressure chamber in stroke simulator and master cylinder; and third hydraulic chamber provided between backpressure chamber and first hydraulic chamber to transmit brake fluid from backpressure chamber to first hydraulic chamber.
    Type: Grant
    Filed: April 24, 2014
    Date of Patent: April 9, 2019
    Assignee: Hitachi Automotive Systems, Ltd.
    Inventors: Hideaki Yagashira, Hiroki Sonoda, Asahi Watanabe, Toshiya Oosawa
  • Publication number: 20180370509
    Abstract: Provided is a brake apparatus capable of securing a braking force on a vehicle even at the time of a fluid leak. The brake apparatus performs control so as to continue generation of a brake hydraulic pressure to be supplied to a wheel cylinder with use of a second hydraulic source if a fluid leak of brake fluid is determined based on a preset relationship between a hydraulic pressure of a first hydraulic source and a stroke of a brake pedal.
    Type: Application
    Filed: November 11, 2016
    Publication date: December 27, 2018
    Inventors: Hideaki YAGASHIRA, Toshiya OOSAWA, Asahi WATANABE
  • Publication number: 20180297569
    Abstract: A brake apparatus includes a master cylinder, a hydraulic source, a reservoir tank, a fluid pool, a fluid level detection unit, and an electronic control unit. The electronic control unit is configured to switch brake control according to the fluid level detected by the fluid level detection unit. The brake fluid is transmitted from the first chamber to the wheel cylinder with use of the master cylinder to increase a pressure in the wheel cylinder. The brake fluid in the second chamber is transmitted to the wheel cylinder with use of the hydraulic source to increase a pressure in the wheel cylinder.
    Type: Application
    Filed: June 22, 2018
    Publication date: October 18, 2018
    Inventors: Toshiya OOSAWA, Asahi WATANABE
  • Patent number: 10046744
    Abstract: An object of the present invention is to provide a brake apparatus capable of acquiring a stable brake performance. A brake apparatus includes a master cylinder configured to be activated according to a brake operation performed by a driver, a reservoir tank divided into at least a first chamber connected to a wheel cylinder via the master cylinder and a second chamber connected to a hydraulic source configured to increase a pressure of brake fluid and transmit the brake fluid to the wheel cylinder, a brake control unit configured to perform brake control of transmitting the brake fluid to the wheel cylinder, and a fluid level detection unit configured to detect a fluid level of the brake fluid in the reservoir tank.
    Type: Grant
    Filed: March 9, 2015
    Date of Patent: August 14, 2018
    Assignee: Hitachi Automotive Systems, Ltd.
    Inventors: Toshiya Oosawa, Asahi Watanabe
  • Publication number: 20180201247
    Abstract: Provided is a master cylinder unit including a simulator pressure chamber which communicates with a pressure chamber of a master cylinder and moves a simulator piston by means of an introduced fluid pressure; a biasing chamber in which a biasing mechanism biasing the simulator piston against a fluid pressure introduced into the simulator pressure chamber is disposed; a first seal member which partitions a simulator supply chamber, the simulator supply chamber, and the simulator pressure chamber communicating with a master supply chamber; and a second seal member which partitions the simulator supply chamber and the biasing chamber and allows a brake fluid to flow from the simulator supply chamber to the biasing chamber when a pressure difference occurs between the simulator supply chamber and the biasing chamber.
    Type: Application
    Filed: July 25, 2016
    Publication date: July 19, 2018
    Inventors: Naganori KOSHIMIZU, Hiroshi OWADA, Toshiya OOSAWA, Ryohei MARUO
  • Patent number: 9988028
    Abstract: A brake apparatus activates a stroke simulator OUT valve in a valve-closing direction to increase a pressure in a wheel cylinder with use of brake fluid flowing out of the stroke simulator according to a state of an operation performed by a driver on a brake pedal. Further, when the hydraulic pressure in the wheel cylinder or a first oil passage is brought into a predetermined state, the brake apparatus activates the stroke simulator OUT valve in a valve-opening direction to cause the brake fluid in the stroke simulator to flow out to a low-pressure portion while restricting the brake fluid in the stroke simulator to a predetermined flow amount.
    Type: Grant
    Filed: August 31, 2015
    Date of Patent: June 5, 2018
    Assignee: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Toshiya Oosawa, Asahi Watanabe
  • Publication number: 20180022332
    Abstract: An object of the present invention is to provide a brake apparatus capable of acquiring a sufficient braking force when an abnormality has occurred. The brake apparatus includes a stroke simulator. The stroke simulator is connected to a portion of an oil passage between a master cylinder and a valve. The oil passage connects the master cylinder and a wheel cylinder therebetween. The stroke simulator is configured to generate a brake operation reaction force due to an increase and a reduction in a volume of a positive pressure chamber formed inside the stroke simulator. Brake fluid contained in a first chamber of the master cylinder flows into the positive pressure chamber at the time of control by a by-wire control unit. A fluid amount that can be supplied from the first chamber is larger than a fluid amount that the positive pressure can absorb therein.
    Type: Application
    Filed: February 9, 2016
    Publication date: January 25, 2018
    Inventors: Hiroki SONODA, Toshiya OOSAWA, Asahi WATANABE
  • Patent number: 9821784
    Abstract: In a system including a reservoir tank RSV integral with a master cylinder M/C, an inlet fluid passage 16 for connecting an inlet portion 22 of a pump P to the reservoir tank RSV, a pressure reducing fluid passage 32 that connects the inlet fluid passage 16 to wheel cylinders W/C and a normally closed pressure reducing vale 30 that is connected to the pressure reducing fluid passage 32 and opened when it is intended to depressurize a brake fluid to in the wheel cylinders thereby to return the brake fluid to the reservoir tank through the inlet fluid passage 16, there is employed a normally closed reservoir shutting valve 31 that is connected to the pressure reducing valve 30 in series with respect to the wheel cylinders W/C and the reservoir tank RSV.
    Type: Grant
    Filed: January 31, 2013
    Date of Patent: November 21, 2017
    Assignee: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventor: Toshiya Oosawa
  • Publication number: 20170282876
    Abstract: A brake apparatus activates a stroke simulator OUT valve in a valve-closing direction to increase a pressure in a wheel cylinder with use of brake fluid flowing out of the stroke simulator according to a state of an operation performed by a driver on a brake pedal. Further, when the hydraulic pressure in the wheel cylinder or a first oil passage is brought into a predetermined state, the brake apparatus activates the stroke simulator OUT valve in a valve-opening direction to cause the brake fluid in the stroke simulator to flow out to a low-pressure portion while restricting the brake fluid in the stroke simulator to a predetermined flow amount.
    Type: Application
    Filed: August 31, 2015
    Publication date: October 5, 2017
    Inventors: Toshiya OOSAWA, Asahi WATANABE
  • Patent number: 9573473
    Abstract: In a vehicle control device, a slip ratio in which front and rear wheels are averaged, and a braking force in which the front and rear wheels are averaged, can be calculated. The vehicle control device is provided with: friction braking devices placed on each wheel; a motor that acts as a regenerative braking mechanism and is placed on the rear wheels; a vehicle slip stiffness calculation unit; a front and rear braking force ratio calculation unit; a vehicle slip stiffness correction unit; and a regenerative braking arithmetic unit. The regenerative braking arithmetic unit operates the friction braking device and the motor so as to make the vehicle slip stiffness reach a vehicle slip stiffness threshold value. Also, the vehicle slip stiffness correction unit corrects the vehicle slip stiffness threshold value in accordance with the ratio of the front wheel braking force and the rear wheel braking force.
    Type: Grant
    Filed: October 1, 2013
    Date of Patent: February 21, 2017
    Assignee: Hitachi Automotive Systems, Ltd.
    Inventors: Yuki Akiyama, Toshiya Oosawa, Atsushi Yokoyama, Makoto Yamakado
  • Publication number: 20170015290
    Abstract: An object of the present invention is to provide a brake apparatus capable of acquiring a stable brake performance. A brake apparatus includes a master cylinder configured to be activated according to a brake operation performed by a driver, a reservoir tank divided into at least a first chamber connected to a wheel cylinder via the master cylinder and a second chamber connected to a hydraulic source configured to increase a pressure of brake fluid and transmit the brake fluid to the wheel cylinder, a brake control unit configured to perform brake control of transmitting the brake fluid to the wheel cylinder, and a fluid level detection unit configured to detect a fluid level of the brake fluid in the reservoir tank.
    Type: Application
    Filed: March 9, 2015
    Publication date: January 19, 2017
    Inventors: Toshiya OOSAWA, Asahi WATANABE
  • Publication number: 20170015293
    Abstract: A system comprises: pump (hydraulic pressure source) that uses brake fluid supplied from reservoir tank (reservoir) to generate hydraulic pressure in first hydraulic line, thereby generating hydraulic pressure in wheel cylinder; piston configured to move axially in cylinder under the action of hydraulic fluid supplied from master cylinder, piston dividing cylinder into at least two chambers (positive pressure chamber and backpressure chamber); stroke simulator for generating reaction force to a driver's brake operation by moving piston; second hydraulic line provided between positive pressure chamber in stroke simulator and master cylinder; and third hydraulic chamber provided between backpressure chamber and first hydraulic chamber to transmit brake fluid from backpressure chamber to first hydraulic chamber.
    Type: Application
    Filed: April 24, 2014
    Publication date: January 19, 2017
    Inventors: Hideaki YAGASHIRA, Hiroki SONODA, Asahi WATANABE, Toshiya OOSAWA
  • Patent number: 9527486
    Abstract: The present invention provides a brake device that can improve the pressure-increasing response of wheel cylinder hydraulic pressure. The invention is provided with: a master cylinder (5) actuated by the driver operating the brake, the master cylinder (5) being connected to a wheel cylinder (8) via a first oil channel (11), and capable of increasing the wheel cylinder hydraulic pressure; and an auxiliary pressure-increasing part (auxiliary pressure-increasing part (106) and stroke simulator (27)) for assisting in the increasing of the wheel cylinder hydraulic pressure by the master cylinder (5) of the pump (7).
    Type: Grant
    Filed: December 9, 2013
    Date of Patent: December 27, 2016
    Assignee: Hitachi Automotive Systems, Ltd.
    Inventors: Ryohei Maruo, Masayuki Saito, Chiharu Nakazawa, Toshiya Oosawa, Asahi Watanabe, Hiroki Sonoda
  • Patent number: 9522668
    Abstract: There is provided a brake apparatus configured to identify a fluid leak spot while generating a braking force. The brake apparatus is configured to drive pump 7 to supply a brake fluid to a first fluid passage (fluid passage 11P, discharge passage 13P) and a second fluid passage (fluid passage 11S, discharge passage 13S), switch communicating valves 23P and 23S alternately between open and closed positions more than once, and detect a brake-fluid leakage in the first or second fluid passage on the basis of magnitudes of detection values detected by hydraulic-pressure sensors 92P and 92S during the open-close switching.
    Type: Grant
    Filed: February 10, 2014
    Date of Patent: December 20, 2016
    Assignee: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Toshiya Oosawa, Hiroki Sonoda, Asahi Watanabe
  • Patent number: 9517766
    Abstract: A parking assist device includes a target steering angle setting section configured to set a target value of the steering angle; a target vehicle speed setting section configured to set a target value of the vehicle speed; an automatic steering control device configured to automatically steer the steering wheel so that the sensed steering angle becomes the target steering angle; an automatic vehicle speed control device configured to automatically control the vehicle speed so that the sensed vehicle speed becomes the target vehicle speed; and a parking space recognizing section configured to recognize a parking space of the host vehicle, the host vehicle being parked within the recognized parking space by the automatic steering control device and the automatic vehicle speed device.
    Type: Grant
    Filed: May 22, 2013
    Date of Patent: December 13, 2016
    Assignee: Hitachi Automotive Systems, Ltd.
    Inventors: Yuki Nakada, Takuya Murakami, Toshiya Oosawa
  • Publication number: 20160001774
    Abstract: A parking assist device includes a target steering angle setting section configured to set a target value of the steering angle; a target vehicle speed setting section configured to set a target value of the vehicle speed; an automatic steering control device configured to automatically steer the steering wheel so that the sensed steering angle becomes the target steering angle; an automatic vehicle speed control device configured to automatically control the vehicle speed so that the sensed vehicle speed becomes the target vehicle speed; and a parking space recognizing section configured to recognize a parking space of the host vehicle, the host vehicle being parked within the recognized parking space by the automatic steering control device and the automatic vehicle speed device.
    Type: Application
    Filed: May 22, 2013
    Publication date: January 7, 2016
    Inventors: Yuki NAKADA, Takuya MURAKAMI, Toshiya OOSAWA
  • Publication number: 20150367828
    Abstract: There is provided a brake apparatus configured to identify a fluid leak spot while generating a braking force. The brake apparatus is configured to drive pump 7 to supply a brake fluid to a first fluid passage (fluid passage 11P, discharge passage 13P) and a second fluid passage (fluid passage 11S, discharge passage 13S), switch communicating valves 23P and 23S alternately between open and closed positions more than once, and detect a brake-fluid leakage in the first or second fluid passage on the basis of magnitudes of detection values detected by hydraulic-pressure sensors 92P and 92S during the open-close switching.
    Type: Application
    Filed: February 10, 2014
    Publication date: December 24, 2015
    Applicant: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Toshiya OOSAWA, Hiroki SONODA, Asahi WATANABE
  • Patent number: 9199639
    Abstract: Vehicular motion control system comprising controller that independently controls driving force and/or braking force of each of four wheels and a turning direction sensor that senses a turning direction, and with an acceleration/deceleration command generator that generates an acceleration/deceleration command based upon a sensed steering angle and sensed vehicle speed and a driving force/braking force distributor that determines the distribution of driving force or driving torque and/or braking force or braking torque of each wheel, and driving force/braking force distributor determines based upon the acceleration/deceleration command and the turning direction so that more driving force or more driving torque and/or more braking force or more braking torque are/is distributed to the inside front wheel in turning than the outside front wheel in turning and more driving force or more driving torque and/or more braking force or more braking torque are/is distributed to the outside rear wheel.
    Type: Grant
    Filed: September 28, 2011
    Date of Patent: December 1, 2015
    Assignee: Hitachi Automotive Systems, Ltd.
    Inventors: Makoto Yamakado, Junya Takahashi, Shinjiro Saito, Toshiya Oosawa
  • Publication number: 20150314765
    Abstract: The present invention provides a brake device that can improve the pressure-increasing response of wheel cylinder hydraulic pressure. The invention is provided with: a master cylinder (5) actuated by the driver operating the brake, the master cylinder (5) being connected to a wheel cylinder (8) via a first oil channel (11), and capable of increasing the wheel cylinder hydraulic pressure; and an auxiliary pressure-increasing part (auxiliary pressure-increasing part (106) and stroke simulator (27)) for assisting in the increasing of the wheel cylinder hydraulic pressure by the master cylinder (5) of the pump (7).
    Type: Application
    Filed: December 9, 2013
    Publication date: November 5, 2015
    Applicant: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Ryohei MARUO, Masayuki SAITO, Chiharu NAKAZAWA, Toshiya OOSAWA, Asahi WATANABE, Hiroki SONODA