Patent ID: 8579386

Claim:
A vehicle brake device including: a brake pedal for receiving a brake pedal stroke; a wheel cylinder provided to a wheel and configured to generate a braking force by using a brake fluid pressure; an electric brake-fluid-pressure generation apparatus for generating a brake fluid pressure to be supplied to the wheel cylinder, by being operated by an electric motor, said electric brake-fluid-pressure generation apparatus operable to carry out a brake-by-wire braking operation under normal operating conditions; and a brake-fluid-pressure control mechanism for controlling vehicle behavior by individually controlling the brake fluid pressure supplied to the wheel cylinder, the brake-fluid-pressure control mechanism being disposed between the electric brake-fluid-pressure generation apparatus and the wheel cylinder, characterized in that the brake-fluid-pressure control mechanism is operable to selectively control operation of the electric brake-fluid-pressure generation apparatus based on either a manual operation of the brake pedal, or a supplemental brake assist operation which may be vehicle stability assist or antilock braking assist; and the brake-fluid-pressure control mechanism includes: an accumulator capable of communicating with the wheel cylinder and the electric brake-fluid-pressure generation apparatus; a first electromagnetic valve configured to switch a communication state of a fluid path that connects the wheel cylinder to the accumulator; and a check valve configured to allow only flowing of a brake fluid from the accumulator to the electric brake-fluid-pressure generation mechanism, and wherein the brake fluid is discharged from the accumulator to the electric brake-fluid-pressure generation apparatus by reducing a driving force of the electric motor of the electric brake-fluid-pressure generation apparatus based on control from the brake-fluid-pressure control mechanism.