| 摘要 |
<p>PROBLEM TO BE SOLVED: To improve follow-up capability of a cylinder body to a surface swing of a disc rotor at the braking time. SOLUTION: A step difference part 6e is formed in a fitting hole 6A to which a main pin 5A is fitted so that a part to which a tip part of the main pin 5A is fitted becomes a small diameter part 6b and its opening end part 6c side becomes a large diameter part 6d. An inside diameter of the large diameter part 6d is set equal to an inside diameter of a fitting hole 6B to which a sub-pin 5B is fitted. A forming position of the step difference part 6e is adjusted to a central position of braking force Fc inputted to a cylinder body 4 at braking time. A groove 6f continuing in the circumferential direction is formed on an inner peripheral surface slightly entering inside from an opening end part 6c of the fitting holes 6A and 6B, and an end part of dust boots 4a composed of a rubber elastic body is inserted into the fitting holes 6A and 6B from the opening end part 6c, and is housed in the groove 6f. Therefore, the main pin 5A and the sub-pin 5B are elastically supported in the opening end part 6c of the fitting holes 6A and 6B by the dust boots 4a.</p> |
