| 摘要 |
PURPOSE: To suppress wear to a minimum so as to improve durability by making a cup member movable together with a spindle, making the spindle abut a sealing ring, and extending the cup member over the free end of a housing. CONSTITUTION: A cup member 10 is movable together with a spindle 1 and makes the spindle 1 and a sealing ring 11 abut each other. The inner diameter of the cup member 10 is larger than the diameter of the spindle 1. The cup member 10 is extended along the spindle 1 over the free end of a housing 7. Only at the time of large axial movement of the spindle 1, force is transmitted to the cup member 10 through abutting between a housing part 9 and an internal abutting part 10' or abutting between a circumferential ridge part 8 of the housing 7 and an internal ring 12 of the cup member 10. Since wear can thus be suppressed to a minimum, durability can be considerably improved. |
