US Patent 7124472 Hinge mechanism with single hand operation

A hinge mechanism includes a shaft having an outer screw thread, a rotating cam, a rotating cam having an inner screw thread, a first elastic element, a sleeve having a latching block, a second elastic element, an anchoring block, and a button having a post. The driven cam defines two symmetrical latching grooves. The anchoring block defines a first hole and a second hole. The shaft extends through the rotating cam, the driven cam, the first elastic element, the sleeve, the second elastic element, and the first hole of the anchoring block. The outer screw thread of the shaft engages with the inner screw thread of the rotating cam. The latching block of the sleeve is slidably received in the latching grooves of the driven cam. The post of the button extends through the second hole of the anchoring block and abuts against an end of the sleeve.