| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a vehicle brake system which can efficiently utilize a brake pedal depression force by an operator of a vehicle as a braking force by decreasing a reaction force to be received by the operator of the vehicle after the system reaches an assisting limit condition. <P>SOLUTION: The vehicle brake system includes: a reaction force generating device for generating in a reaction force chamber, a reaction force pressure corresponding to a displacement amount of an input piston; a change over valve provided in an open passage branched from a hydraulic conduit connecting the reaction force generating device to the reaction force chamber; a brake force boosting device which generates assisting pressure by controlling brake fluid having actual accumulator pressure accumulated in an accumulator in accordance with brake pedal depression force or operation amount of the brake pedal and supplies the assisting pressure to an assisting pressure chamber of a master cylinder, thereby acting thrust force obtained by boosting the pedal depression force on a master piston; an assisting pressure limit determining part for determining whether prescribed condition showing that the assisting pressure generated by the brake force boosting device has reached an assisting limit pressure, is satisfied; and a change over controlling part for changing over the change over valve to an open state when the assisting pressure limit determining part determines that the prescribed condition is satisfied. <P>COPYRIGHT: (C)2013,JPO&INPIT |
