| 摘要 |
PROBLEM TO BE SOLVED: To restrain fluctuation of fluid pressure supplied for boosting to secure excellent braking operation feeling in a hydraulic brake device for a vehicle provided with a hydraulic booster means. SOLUTION: In this device, a control piston 30 exposing its rear side to a pressure chamber R4 and forming a regulator chamber R6 in its front side is liquid-tightly and freely slidably stored in the front of a master piston 20 inside a cylinder body 1, being arranged to interlocking to the master piston 20. Provided are a boost pressure poppet valve mechanism 60 interlocking to the control piston 30 to communicate or block a sub-hydraulic source 40 to a power chamber R1, a pressure reducing spool valve mechanism 50 interlocking to the control piston to communicate or block the power chamber to a reservoir 4, and a unidirectional valve means (a check valve 80) allowing only a flow of brake fluid supplied from the boost pressure poppet valve mechanism 60 to the power chamber. |
