MASTER CYLINDER, SEAL RETAINER FOR MASTER CYLINDER, AND SEAL RETAINER INSTALLING METHOD

摘要

PPROBLEM TO BE SOLVED: To provide a master cylinder reduced in the number of parts items by securely structuring a seal retainer in the master cylinder, with a simple structure. PSOLUTION: Inside a cylinder bore 1, a relay annular groove 1b is formed toward a rear opening end and a holding annular grooves 1c and 1d having a diameter larger than that of the relay annular groove are formed. A seal retainer 30 having an annular vertical wall part 31 extended in a U-shape groove of an annular seal member S1 and an annular step part 32 formed in the inner peripheral side to abut on the opening side end surface of the U-shape groove is formed to be shrunken in response to the pushing force generated in the radial direction when installing in the cylinder bore 1a and to be restored when the pushing force is released (for example, a part in the circumferential direction is cut). After arranging the seal retainer 30 in the shrunken condition from the cylinder bore to the relay annular groove 1b, the seal retainer is transferred to the holding annular groove 1c. In the condition that the vertical wall part is extended in the U-shape groove of the seal member, the seal retainer is restored. PCOPYRIGHT: (C)2004,JPO&NCIPI