Patent ID: 8547046

Claim:
A controller for a door closer comprising: a drive gear configured to rotate in response to movement of a door; a chain arranged to cooperate with the drive gear to produce linear motion in response to rotation of the drive gear in response to the movement of the door; a generator responsive to rotational motion to generate electricity to power the controller; control circuitry disposed to be powered by the generator, the control circuitry including a connection to control a valve in the door closer; a power management circuit connected between the generator and the control circuitry to store energy and supply voltage to the control circuitry wherein the voltage is increased when the movement of the door does not provide sufficient energy to power the control circuitry; at least one gear to turn the generator in response to the linear motion of the chain; and a set of clutch gears disposed between the chain and the at least one gear so that only one direction of the rotational motion is transferred to the generator in response to movement of the door in any direction.