| 摘要 |
The insulative support bracket of a surge arrester includes a concentric annular concavity formed at one or both ends of a bolt hole. A washer, when pressed concentrically to the concavity, contacts the insulative bracket only, at least initially, at surfaces adjacent the outer diameter of the washer. An annular convexity, surrounding the concavity, will mate with the central portion of an external tooth lockwasher to prevent the full penetration of the teeth of the lockwasher into the insulative bracket. The ability of the insulative bracket to withstand the mechanical forces transmitted to the insulative bracket by the washers is thereby enhanced. The concavity may be formed either in a surface of the insulative bracket or in a surface of the washer. |
