| 摘要 |
PURPOSE:To enable wire rings to be prevented from their early wearing, by holding the wire rings by a U-shaped clip and obtaining a large contact area formed between the U-shaped clip and the wire rings. CONSTITUTION:Wire rings 21, 22 and a U-shaped clip 24 are arranged in the central part in the cover radius direction of an oval-shaped hole 18. The wire ring 21 is supported to a curved part of the U-shaped clip 24 while long in a cover circumferential direction by the U-shaped clip 24 of strip shape. Accordingly, the wire rings 21, 22 are supported in a manner of surface or line contact by the U-shaped clip 24 of strip shape, and the wire rings 21, 22 are prevented from also their early wearing because of the large contact area. |
