摘要 |
A master cylinder has a resin cylinder main body formed with a step at a boundary between a cylinder hole and a mount hole. A piston cooperates with the inner circumferential surface of the cylinder hole to define a hydraulic chamber. A guide sleeve is locked in the cylinder main body and guides a base end of the piston. A first annular sealer, which has an inner seal member made of a soft material and an outer seal member made of a hard material, is held on the outer circumferential surface of a leading end of the piston. A second annular sealer is squeezed between the step and a leading end of the guide sleeve. At least a portion of the outer circumferential surface of the piston is made of a metal. The master cylinder is inexpensive and suppresses squeaks and rattles caused by the stick-slip phenomenon. |