Hitachi Automotive Systems, Ltd.

Asahi Watanabe

Toshiya Oosawa

Hiroki Sonoda

Chiharu Nakazawa

Ryohei Maruo

Masayuki Saito

Hiroshi Furuyama

Hideaki Yagashira

Toshiya Osawa

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.

Brake control system, brake system, and brake hydraulic pressure generating method

It is an object of the invention to provide a brake device capable of detecting a failure in each of components, by which booster control is performed, at an early stage even during vehicle running. The brake device is configured to discharge brake fluid into a communicating fluid path that connects a fluid path of a primary system and a fluid path of a secondary system, and to control a first communicating valve for restricting a flow of brake fluid from the communicating fluid path to the fluid path of the primary system and a second communicating valve for restricting a flow of brake fluid from the communicating fluid path to the fluid path of the secondary system in respective valve-closing directions, so as to check at least a state of the pump.

Brake device

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. The brake control unit is provided so as to be able to perform first brake control of transmitting the brake fluid from the first chamber to the wheel cylinder with use of the master cylinder, thereby increasing a pressure in this wheel cylinder, and second brake control of transmitting the brake fluid in the second chamber to the wheel cylinder with use of the hydraulic source, thereby increasing a pressure in this wheel cylinder. The brake control unit switches brake control between the first brake control and the second brake control according to the fluid level detected by the fluid level detection unit.

Brake apparatus

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.

To provide a brake control apparatus that brings a brake operating member to a proper position during antilock control. At least during operation of an antilock controller, valvesandare actuated to impart a stroke to a pistonP with hydraulic pressure generated by the pump

Brake control apparatus and brake control method

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 () actuated by the driver operating the brake, the master cylinder () being connected to a wheel cylinder () via a first oil channel (), and capable of increasing the wheel cylinder hydraulic pressure; and an auxiliary pressure-increasing part (auxiliary pressure-increasing part () and stroke simulator ()) for assisting in the increasing of the wheel cylinder hydraulic pressure by the master cylinder () of the pump ().

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 pumpto supply a brake fluid to a first fluid passage (fluid passageP, discharge passageP) and a second fluid passage (fluid passageS, discharge passageS), switch communicating valvesP andS 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 sensorsP andS during the open-close switching.

A control apparatus for a vehicle, comprising a control unit having: a resultant acceleration information calculating section () configured to calculate a resultant acceleration which is a synthesis of two direction accelerations acted upon the vehicle; a resultant jerk calculating section () configured to calculate a resultant jerk of at least one of change rates of the two directional accelerations with respect to time and a change rate of the resultant acceleration with respect to time; and a rollover tendency determining section () configured to determine a tendency of rollover of the vehicle using at least one of the calculated resultant acceleration and the calculated resultant jerk.

Apparatus for determining vehicle rollover risk

A brake control system of a motorcycle is provided which can suppress a malfunction of an anti-lock braking system applied to a rear wheel which would be caused by an abnormal speed difference between the front and rear wheels. A threshold value for a skid rate for the rear wheel is kept to a second skid rate threshold value until a time when a predetermined condition is established. The second skid rate threshold value is larger than a first skid rate threshold value that is usually employed.

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Kawasaki, Japan

Asahi Watanabe