Abstract: A snap hinge assembly for rotatably connecting a flip cover to a portable phone housing has only two parts, a hinge pin and a spring. The hinge pin is rotatably mounted in the housing and secured to the cover so as to rotate with the cover as it is opened and closed, and has a cam portion for engaging the spring. The spring is anchored in the housing and has a bearing portion for bearing against the cam portion as the pin rotates with the cover. The shape of the cam portion is such that the bearing portion is resiliently biased as the hinge pin rotates, and released at a predetermined orientation so as to snap the cover into either the open or closed position, depending on the direction of rotation of the pin. The cover is held by the engaging spring and cam surfaces in the open or closed position until positively urged towards the opposite end position.

Abstract: A hinge apparatus has relatively rotatable first and second parts, one of which is adapted to be secured to the phone housing and the other of which is adapted to be secured to a cover. One of the parts comprises a cam and the other comprises a follower, the cam having end stops corresponding to an open and a closed position of the cover relative to the housing, and a convex surface between the end stops to provide initial resistance to rotation of the cover out of the open and closed positions. The parts are spring loaded such that the cover is snapped into the open and closed positions, respectively, once the follower passes the arcuate surface of the cam.