WHEEL BRAKE CYLINDER

摘要

PROBLEM TO BE SOLVED: To easily carry out machining at a low cost by supporting a ring type seal member arranged in the major diameter part of a cylinder by means of a plug which is provided with a hole and is inserted into the cylinder major diameter part and assembling a boot to a piston and to the plug. SOLUTION: A D-ring 4 is inserted into the inside of a major diameter part 2b in a cylinder 2, while a plug 5 is fitted to the major diameter part 2b from the truncated conical bottom part side, and the D-ring 4 is held in the cylinder 2 by means of a stepped part 2e between the major diameter part 2b and a minor diameter part 2c and one end side of the plug 5. A snap ring 7 is elastically engaged in a groove 2d in the major diameter part 2b and is locked in a locking part 5c in the plug 5 at the same time so as to be fixed in the cylinder 2. A piston 3 is inserted slidably into an inner hole 5a of the plug 5, the D-ring 4 inner circumference, and the minor diameter part 2c, while a pressure chamber 8 is formed on the right end face side. Subsequently, an inner circumference part 6a of a boot 6 is installed in a groove 3a in the piton 3 while its outer circumference part 6b is installed in a groove 5b in the plug 5. In this way, polishing of the cylinder 2 inner circumferential face is not needed, and polishing of the piston 3 outer circumferential face can be easily carried out at a low cost.