POLYGONAL WASHER AND FASTENING STRUCTURE

原文（中国語）

Provided are a asher that is simple structure and controls the simultaneous turning of the washer. Disclosed is a polygonal washer 1 is used between a mounting surface Sa of an object to be attached S and a nutor a bolt head. The polygonal washercomprises a washer bodyA. The washer bodyA has a polygonal shape, seen from an orthogonal direction against the nut. Central recessAa is formed on the mounting surface Sa side. As for the configuration of the central recessAa, it is equal to the configuration of the nutor, it is equal to the head of a bolt, or it is formed more greatly than the nutor it is formed more greatly than the configuration of the head of the bolt. As a result, when it is tightened with the nutor the bolt, the center portion of the main bodyA of the washer has the elasticity displaced to the mounting surface side Sa is possessed.