Patent ID: 8250710

Claim:
A hinge comprising: a fixing member; a shaft non-rotatably fixed to the fixing member, the shaft comprising a shaft post; a rotating member rotatably sleeved on the shaft post; an interfering assembly comprising a male element and a female element rotatable relative to the male element, the male element non-rotatbly fixed to the shaft post, a first raised portion and a second raised portion protruding from the male element, the female element defining a through hole in a center of the female element; wherein the shaft post is rotatably extended through the through hole of the female element, a circularly shaped sliding surface protrudes from a side of the female element, a center of the sliding surface is apart from a center of the through hole, an inner slot adjacent to the through hole and an outer slot adjacent to a circumference of the female element are formed beside the sliding surface, a width of the inner slot is gradually varied along an edge bounding the through hole, and a width of the outer slot is gradually varied along the circumference of the female element; the female element defines a first depressed portion abutting against the inner slot, and a second depressed portion abutting against the outer slot, the first and second depressed portions are correspondingly engaged with the first and second raised portions; an elastic assembly rotatably sleeved on the shaft post, to provide elasticity along an axis of the shaft post to tighten the interfering assembly and the rotating member; and a fastener fixed to a distal end of the shaft post; wherein when the rotating member is rotated relative to the fixing member, the first and second raised portions are slid out from the first and second depressed portions, respectively, in frictional engagement with the sliding surface, together with partial portions of the first and second raised portions covering the inner and outer slots, correspondingly, thereafter, the region of friction between the first and second raised portions and the sliding surface is varied.