Patent ID: 7780246

Claim:
A brake system, comprising: a master cylinder which generates brake fluid pressure based on a brake operation of a driver; a reservoir which is fluidly connected to the master cylinder; a wheel cylinder which brakes a wheel; a pedal stroke sensor which is operable to detect the brake operation of the driver; a fluid pressure generator, the fluid pressure generator comprising: a generator cylinder; a first port which communicates with the master cylinder; a second port which communicates with the wheel cylinder; and an electrically operated piston disposed in the generator cylinder which generates brake fluid pressure; a normally open shutoff valve disposed between the master cylinder and the fluid pressure generator; a first fluid passage extending between the master cylinder and the shutoff valve; and a second fluid passage extending between the shutoff valve and the fluid pressure generator; wherein said first and second fluid passages cooperate to provide an exclusive channel of fluid communication between the reservoir and the fluid pressure generator; wherein an operation of the fluid pressure generator is started based on a brake operation detection signal of the pedal stroke sensor, and wherein the piston of the fluid pressure generator closes the first port before a piston of the master cylinder closes a refilling port connected to the reservoir.