| 摘要 |
PROBLEM TO BE SOLVED: To reduce limitation in design to the upmost, and to secure excellent boosting responsiveness in a hydraulic brake device for vehicle with hydrauic boosting 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. Disposed are a boost pressure poppet valve mechanism 60 interposed in the first hydraulic passage P1 communicatingly connecting a sub-fluid pressure source 40 to a power chamber R1 and interlocking to the control piston 30 to open and close the first fluid pressure passage P1, and a pressure-reducing spool valve mechanism 50 interposed in the second hydraulic passage P2 communicatingly connecting the power chamber to a reservoir 4 via the regulator chamber R6 and interlocking to the control piston to open and close the second hydraulic passage. |
