| 摘要 |
PURPOSE:To reducce moving of chassis due to braking when backing by performing pressure reduction control of front wheel side brake when backing, while never reducing the pressure of the same when advancing. CONSTITUTION:Upon stepping of brake pedal under advancing, the liquid pressure in master cylinder is fed through a contact hole 10, a chamber 77, a hole 29 in main piston, a stepped hole 30 in axial direction, a hole 28 and a connection hole 11 to the wheel cylinder of front wheel thus to function the front wheel brake. Said liquid pressure is also transmitted through a path 52, a valve system 76, a through-hole 45 of control piston and a path 53 into the control pressure chamber 27. Consequently, main piston 20 will never move even upon pressure rise, thus to never execute pressure reduction control. While when backing, coil 37 is excited to close the valve system 76. Since the liquid pressure in master cylinder is never fed into the control pressure chamber 27, main piston 20 will move to the left upon pressure rise in master cylinder, thus to execute pressure reduction control. |
