| 摘要 |
PURPOSE:To shorten strokes of a brake pedal and secure the braking force for the time when a drive motive is out of operation by making a power piston with a greater dia. than the master piston, installing the power piston and master piston adjoiningly each other with a sealed chamber interposed, and by coupling fluidly. CONSTITUTION:When a power hydraulic pressure source is in normal operation and the emitted power hydraulic pressure puts a hydraulic pressure booster 20 in normal function, power doubled drive is made by the hydraulic pressure booster 20, and brake operation is made with brake pedal 2 strokes shortened by a power piston 5, master piston 11, and a sealed chamber 4 to couple them fluidly. This causes insufficient doubling function of the hydraulic pressure booster, and this function is no more obtainable, the master cylinder 10 directly responds to the brake pedal 2, and the output brake hydraulic pressure of the master cylinder 10 is applied to the wheel cylinders 51a-54a. |
