| 摘要 |
PROBLEM TO BE SOLVED: To provide a master cylinder which prevents inversion of a seal member which seals a cylinder body with a simple structure.SOLUTION: An annular seal member 33 which shields an interior part of a cylinder body from outer air is housed in a groove part 15 formed at an entire periphery of an inner peripheral surface of the cylinder body. The groove part 15 includes: a bottom surface 15a which contacts with an outer lip 33b of the seal member; a rear wall surface 15b which extends from a cylinder body opening side end part of the bottom surface 15a to a radial inner side; a first front wall surface 15c extending from a cylinder body bottom part side end part of the bottom surface 15a to the radial inner side; an inclined wall surface 15d which is connected to the first front wall surface 15c and inclines to the cylinder body bottom part side toward the radial inner side; and a second front wall surface 15e which is connected with the inclined wall surface 15d at the opposite side of the first front wall surface 15c and extends to the radial inner side.SELECTED DRAWING: Figure 2 |
