| 摘要 |
PROBLEM TO BE SOLVED: To obtain the excellent braking operation feeling by the two-step hydraulic pressure characteristic in a normal braking operation after dispensing with or reducing the size of a negative pressure booster, and to rapidly boost the brake hydraulic pressure in an emergency braking operation. SOLUTION: As the detected value of a detector 29 to detect the index corresponding to the operational force of a braking member 4 is changed from a nonboosting area of not more than a first preset threshold to a boosting area exceeding the first threshold, a pump 10, a selector valve means 25 and a pressure regulating means 14 are controlled by a control unit 28, and the pressure regulating means 14 is controlled in the normal braking operation so that the braking hydraulic pressure following the two-step normal hydraulic pressure characteristic according to the change of the detected value is applied to wheel brakes BF, BR. In the emergency braking operation, the pressure regulating means 14 is controlled so that the braking hydraulic pressure following the emergency hydraulic pressure characteristic to rapidly boost the braking hydraulic pressure to the upper limit value is applied to the wheel brakes BF, BR. |
