| 摘要 |
<P>PROBLEM TO BE SOLVED: To surely operate a wheel cylinder of one system when a liquid passage of the other system fails during braking by brake fluid pressure generated by a master cylinder in a BBW (brake-by-wire) type braking device. <P>SOLUTION: When the liquid passage Qc for connecting a front fluid pressure chamber 39B of a slave cylinder 23 and the wheel cylinder fails, the fluid pressure of the front fluid pressure chamber 39B is lost and a front piston 38B is advanced in relation to a rear piston 38A. There is a possibility of lowering the brake fluid pressure supplied to the wheel cylinder by expanding a volume of a rear fluid pressure chamber 39A. By regulating a maximum distance between the rear piston 38A and the front piston 38B by a regulation means 62, the volume of the rear fluid pressure chamber 39A is prevented from being expanded even if the fluid pressure of the front fluid pressure chamber 39B is lost, and the wheel cylinder is surely operated to secure a braking force. <P>COPYRIGHT: (C)2008,JPO&INPIT |
