| 摘要 |
A washer 210 has a first face 211 for abutment by a threaded fastener and a second relieved face 212 for abutment against an object to be secured in position by the threaded fastener. The relieved face 212 is configured to ensure that initial contact between the washer 210 and the object occurs at an outer peripheral edge 212e of the relieved face 212 thereby maximising the radius of contact between the washer 210 and the object and reducing the risk of the washer 210 slipping when the threaded fastener is tightened. The relieved face 212 may be concave or more particularly a frusto-conical concave face, or may be a concave spherical surface. |
