Patent ID: 9732783
Date: 2017-08-15
CPC Classifications: F16B

Claim:
1. An anti-loosening bolt assembly comprising: a bolt having a bolt head and a bolt shank, wherein the bolt shank vertically extends from the bolt head, the bolt shank having first threads formed on an outer circumferential surface thereof; a fixed nut having second threads on an inner circumferential surface thereof, the second threads being engaged with the first threads of the bolt; and a washer arranged between the bolt and an objective member to be fastened by the bolt, wherein the bolt head includes a plurality of locking protrusions provided on the lower surface thereof in a circumferential direction of the bolt head, each of the locking protrusions having an inclined locking surface and a vertical locking surface, wherein the inclined locking surface is provided by having an inclination on the lower surface of the bolt head, and the vertical locking surface connects the inclined locking surface with a neighboring inclined locking surface, and an upper end part of the inclined locking surface is directed to a loosening direction of the bolt, and a lower end part of the inclined locking surface is directed to a tightening direction of the bolt, the washer includes a plurality of stop protrusions provided on an upper surface thereof in a circumferential direction of the washer, each of the stop protrusions having an inclined stop surface and a vertical stop surface, wherein the inclined stop surface is provided by having an inclination on the upper surface of the washer, and the vertical stop surface connects the inclined stop surface with a neighboring inclined stop surface, and an upper end part of the inclined stop surface is directed to a loosening direction of the bolt, and a lower end part of the inclined stop surface is directed to a tightening direction of the bolt, and a magnetic member is provided in the washer such that the magnetic member maintains a combined state of the washer with the objective member using a magnetic force, so that when a rotational force is applied to the bolt in the loosening direction, the inclined locking surface of the bolt is stopped by the inclined stop surface of the washer, thereby preventing the bolt from loosening and rotating.