| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a fluid pressure booster for a braking device including a control piston on which an input brake operation acts in an advancing direction, and a reaction force based on fluid pressure of a booster fluid pressure generation chamber acts in a retracting direction, a pressure increasing valve provided between a valve chamber communicating with a fluid pressure generation source and the booster fluid pressure generation chamber so as to open according to the advance of the pressing rod at the time of advance of the control piston, and a pressure reducing valve provided between a release chamber communicating with a reservoir and the booster fluid pressure generation chamber so as to close at the time of advance of the control piston, while preventing abnormal noise due to abrupt fluid pressure flow when the pressure increasing valve is opened. <P>SOLUTION: A contraction portion 140 for gradually increasing flow area depending on the movement of the pressing rod 124 to an advance side in a valve housing 97 is provided on a flow passage 135 that is formed in the valve housing 97 so as to allow the fluid pressure generation source to communicate with the booster fluid pressure generation chamber 40 when the pressure increasing valve 43 is opened. <P>COPYRIGHT: (C)2012,JPO&INPIT |
