Patent ID: 8375519

Claim:
In a signal activated door hinge for remotely closing a door by a low voltage electric signal, said signal activated door hinge comprising: (a) an internal mechanical activation mechanism, (b) a left hinge plate connected to said internal mechanical activation mechanism and affixed to a stationary door frame; (c) a right hinge plate connected to said internal mechanical activation mechanism and affixed to a movable door; (d) a cylindrical cover tube surrounding and connected to said internal mechanical activation mechanism; and (e) external low voltage electrical wiring attached to said cover tube and further connected to said internal mechanical activation mechanism; whereby an external low voltage electrical charge applied to said external low voltage electrical wiring maintains said internal mechanical activation mechanism in a readiness mode, and a subsequent low voltage electric activation signal applied to said external low voltage electrical wiring interrupts said electrical charge, thereby converting said readiness mode to an activation mode whereby said internal mechanical activation mechanism moves said right hinge plate to close said movable door: The internal mechanical activation mechanism comprising: an upper pivot; an upper bushing adjacent to said upper pivot; an upper sprocket adjacent to said upper bushing; a lower bushing adjacent to said upper sprocket; a middle sprocket adjacent to said lower bushing; an activation spring attached to inner surfaces of said upper sprocket and said middle sprocket; a lower sprocket attached to said right hinge plate adjacent to said middle sprocket; and a drop shaft assembly attached to said middle sprocket.