Vehicle brake system

A vehicle brake system comprising:

• a booster device for boosting the braking manipulation force exerted on a brake pedal;
• a master cylinder operatively connected to the booster device;
• a reservoir tank storing brake fluid for replenishing brake fluid to the master cylinder;
• wheel brakes provided for respective vehicle wheels and connected to the master cylinder;
• a hydraulic pressure control device interposed between the master cylinder and the wheel brakes and having a pump for drawing operating fluid on the side of the master cylinder to discharge the operating fluid toward the side of the wheel brakes and a hydraulic pressure control valve capable of restraining the flow of the operating fluid from the side of the wheel brakes toward the side of the master cylinder;
• a stroke sensor for detecting the moving stroke of the brake pedal;
• a simulator for applying to the brake pedal a pseudo reaction force corresponding to the moving stroke of the brake pedal;
• a fluid absorbing mechanism arranged between the master cylinder and the hydraulic pressure control device and configured to operate only in a state that communication between the master cylinder and the reservoir tank is blocked, for absorbing the moving stroke of the brake pedal by a predetermined amount;
• and
• a cut valve arranged between the master cylinder and the fluid absorbing mechanism for blocking the communication between the maser cylinder and the fluid absorbing mechanism when an abnormality in the system causes the pump to be incapable of discharging pressurized fluid.

A vehicle brake system comprising:

• a booster device for boosting the braking manipulation force exerted on a brake pedal;
• a master cylinder operatively connected to the booster device;
• a reservoir tank storing brake fluid for replenishing brake fluid to the master cylinder;
• wheel brakes provided for respective vehicle wheels and connected to the master cylinder;
• a hydraulic pressure control device interposed between the master cylinder and the wheel brakes and having a pump for drawing operating fluid on the side of the master cylinder to discharge the operating fluid toward the side of the wheel brakes and a hydraulic pressure control valve capable of restraining the flow of the operating fluid from the side of the wheel brakes toward the side of the master cylinder;
• a stroke sensor for detecting the moving stroke of the brake pedal;
• a simulator for applying to the brake pedal a pseudo reaction force corresponding to the moving stroke of the brake pedal;
• and
• means for absorbing the moving stroke of the brake pedal by a predetermined amount arranged between the master cylinder and the hydraulic pressure control device and configured to operate only in a state that communication between the master cylinder and the reservoir tank is blocked.