| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent a knock back of a caliper piston effectively so as to prevent an initial braking from being delayed due to increase in the play stroke of a brake operating element and an operating stroke of a caliper piston for maintaining a satisfactory brake feeling, and also prevent an initial braking from being delayed by a caliper piston pulled back o the bottom part of a caliper cylinder hole beyond a specified backward position when brake fluid contained in a hydraulic line is expanded or contracted by braking heat so as to maintain a brake feeling satisfactory. SOLUTION: A relief valve 29 for cutting off a communication between a storage fluid chamber 15 and a master fluid pressure chamber 12 is installed to a relief port 16. The relief valve 29 is set to that it is opened at a pressure range between an operating start fluid pressure and an independent operating fluid pressure. A fluid pressure below the independent operating fluid pressure of the caliper piston 26 is set in a hydraulic pressure line between the master fluid pressure chamber under non-operation and a caliper fluid pressure chamber 28. A float valve 33 is installed in the relief valve 29. Also the float valve 33 is set so that the valve is opened as the brake fluid contained in the fluid pressure line is cooled after completing a brake operation and to contract its volume.</p> |
