| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a fluid pressure booster for a braking device including first and second valve means sequentially opened according to the advance of a pressing rod at the time of advance of a control piston where brake operation input acts in an advance direction, a pressure increasing valve provided between a booster fluid pressure generation chamber and a valve chamber communicating with a fluid pressure generation source, and a pressure reducing valve interposed between the booster fluid pressure generation chamber and a release chamber communicating with a reservoir so as to be closed at the time of advance of the control piston, while achieving proper brake operation feeling by decreasing a valve opening operation force of the second valve means after the first valve means is opened. <P>SOLUTION: A flow passage 135 for allowing the valve chamber 42 to communicate with the booster fluid pressure generation chamber 40 when the first valve means is opened, is formed in a valve housing 97 so as to surround at least a part of the pressing rod 124. A contraction portion 140 to decrease a fluid pressure difference between fluid pressure of the valve chamber 42 and fluid pressure applied to a valve seat member 119 on the downstream side with respect to the first valve means 116 is provided on the downstream side of the flow passage 135. <P>COPYRIGHT: (C)2012,JPO&INPIT |
