Patent ID: 7987556

Claim:
A hinge comprising: a first bracket; a shaft fixed to the first bracket; a second bracket rotationally fitting about the shaft; a first interference element rotationally mounted on the shaft and fixed to the second bracket, the first interference element defining at least two unleveled surfaces at one side surface thereof facing away from the second bracket, and comprising at least two protrusions respectively protruding from the at least two unleveled surfaces; a second interference element immovably mounted on the shaft and beside the first interference element, the second interference element defining at least two unleveled surfaces at one side surface thereof facing and correspondingly mating with the at least two unleveled surfaces of the first interference element, and at least two recessions respectively located on the at least two unleveled surfaces of the second interference element and corresponding to the at least two protrusions of the first interference element; and fastening means capable of keeping the first interference element and the second interference element in contact on the shaft; and a plurality of washers mounted to the shaft to provide elastic forces along an axial direction of the shaft to press the second bracket, the first interference element, and the second interference element to firmly resist against each other.