| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a disc brake capable of satisfactorily pulling a piston back, with a simple configuration.SOLUTION: An inner peripheral wall surface 24 of a cylinder body 21 includes: a first inner peripheral wall surface 241; a second inner peripheral wall surface 242 which is formed on a fluid inlet/outlet port 25 side with respect to the first inner peripheral wall surface 241, and whose inner diameter is smaller than that of the first inner peripheral wall surface 241; and a third inner peripheral wall surface 243 connected to the first inner peripheral wall surface 241 and the second inner peripheral wall surface 242. A piston 22 includes: a first side surface 271 which faces the first inner peripheral wall surface 241 with an interval; a second side surface 272 which faces the second inner peripheral wall surface 242 with an interval; and a third side surface 273 which faces the third inner peripheral wall surface 243 with an interval. A piston seal 23 includes: a first piston seal 231 which comes into contact with the first inner peripheral wall surface 241 and the first side surface 271 fluid-tightly; and a second piston seal 232 which comes into contact with the second inner peripheral wall surface 242 and the second side surface 272 fluid-tightly.</p> |
