| 摘要 |
A packing ring 10 has a number of axially protruding projections 20 arranged with mutual spacing in a circumference on one of its surfaces. In use, the packing ring is mounted inside a circumferential recess which is wider than the distance between the radial surfaces 11, 12 on the packing ring, and the projections 20 prevent the ring moving axially inside the recess and allow simultaneous swelling of the ring in the axial direction between the projections, so that the outer stability of the outer surface 14 in the packing ring is maintained. The packing ring is especially useful in a hydraulic damper which works in only one direction, and a door closer which uses such a damper. <IMAGE> |
