Patent ID: 6859978

Claim:
A hinge mechanism with an auto-lock function for coupling a main body and a rotating object, the hinge mechanism comprising: a sleeve shaft with a torsion spring chamber, located on the rotating object, wherein the torsion spring chamber extends along a hinge mechanism longitudinal axis and the sleeve shaft has a first opening and a second opening; a first bush having a first bush connecting end, disposed within the torsion spring chamber, for sliding along the hinge mechanism longitudinal axis, wherein the first bush connecting end passes through the first opening and protrudes outside the sleeve shaft; a second bush having a second bush connecting end, rotatably disposed within the torsion spring chamber, wherein the second bush connecting end passes through the second opening and protrudes outside the sleeve shaft; a torsion spring having a first spring end connected to the first bush and a second spring end connected to the second bush, disposed between the first bush and the second bush, wherein the second spring end rotates relative to the first spring end to produce energy for unfolding the rotating object when the second bush rotates relative to the first bush; and a first chute and a second chute, disposed on the main body, wherein the first chute receives the first bush connecting end and the second chute receives the second bush connecting end; wherein the rotating object rotates relative to the main body around the hinge mechanism longitudinal axis to be unfolded by releasing the energy from the torsion spring.