| 摘要 |
PROBLEM TO BE SOLVED: To simultaneously output brake fluid pressures by a plurality of secondary master cylinders at all times by reducing the number of components in a brake fluid pressure booster capable of boosting a wheel brake. SOLUTION: A proportional booster valve V comprises a control piston 23 having one end facing to a first control fluid pressure chamber 25 to which one of a pair of output ports provided in a tandem type primary master cylinder is connected, a free piston 24 having both ends facing to a second control fluid pressure chamber 27 to which the other of the both output ports is connected and the first control fluid pressure chamber 25, a reaction means 40 applying a reaction responding to the fluid pressure of a booster fluid pressure chamber 44 commonly connected to a plurality of secondary master cylinders to the control piston 23, and a valve means 50 operated according to the axial movement of the control piston 23, drawing the fluid pressure proportional to the output fluid pressure of the primary master cylinder from a fluid pressure source 12, and introducing it to the booster fluid pressure chamber 44. |
