| 摘要 |
<p>PURPOSE: To prevent deterioration in sealing performance even when a plug body is deformed caused by liquid pressure in a structure in which a cylinder hole is formed by blocking a large diameter part of a processing hole on the side opposite to a disc rotor by means of the block body. CONSTITUTION: A plug body 31 has a bottomed cylindrical shape composed of a cylindrical part 31a and a bottom wall 31b. A seal member 32 is installed on a seal groove 31d of the plug body 31. A male screw 31c on an outer periphery is screwed with a female screw 30c of a processing hole 30. A large diameter side of the processing hole 30 is blocked by the bottom wall 31b on the side opposite to a disc rotor. A cylinder hole 24 is composed of an inner peripheral part of the cylindrical part 31a and a small diameter part of the process hole 30. The seal member 32 is press-fitted to an inner peripheral side stepped portion 30a, for liquid-tightly sealing the cylinder hole 24. When liquid pressure of a liquid pressure chamber 28 is applied to the whole of the plug body 31 as an inner pressure, press-fitting force of the seal member 31 is not weakened.</p> |
