| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a master cylinder capable of obtaining sufficient fast fill performance even under high pressure. SOLUTION: A stepped piston 16 is formed with a check valve 201 which partitions the inside of a step-bore cylinder into a large-diameter pressure chamber 56 on large-diameter piston section 46 side and a small-diameter hydraulic pressure chamber 49 on small-diameter piston section 46 side, is opened an closed by movement of a valve body 200, and permits only flow of brake fluid from the large-diameter pressure chamber 56 side to the small-diameter hydraulic pressure chamber 49 side. If a decrease in the volume of the large-diameter pressure chamber 56 is generated by sliding of the stepped piston 16 to the small-diameter hydraulic pressure chamber 49, the valve element 200 of the check valve 201 moves to open a flow passage completely, thus supplying fluid from the large-diameter pressure chamber 56 side to the small-diameter hydraulic pressure chamber 49 side with a sufficient flow passage cross section.</p> |
