Patent ID: 7913359

Claim:
A hinge assembly for being rotated between an opened state and a closed state, comprising: a shaft defining a thread; a cam having a cam surface at one end thereof, the cam defining a cam hole and an inner circumferential surface, the inner circumferential surface including a protrusion, the protrusion spaced from the thread of the shaft when the hinge assembly is in the closed state; a follower having a latching cam surface engaging with the cam surface of the cam; a first spring causing the cam surface of the cam and the latching cam surface of the follower to resist each other; a control member having at least one reverse slot; a second spring positioned between the control member and the follower; and a fixing seat placed around the control member, the fixing seat having an inner circumferential wall, the inner circumferential wall including at least one block; the at least one block being received in the at least one reverse slot of the control member so as to lock the control member into the fixing seat; wherein when the control member is released from the fixing seat, the control member and the cam are movable relative to the fixing seat to allow the protrusion to engage the thread of the shaft to automatically rotate the cam under the force of the first spring to the open state.