US Patent 7971316 Door closer assembly

A door closer assembly is provided, including a valve regulating an amount of hydraulic fluid that flows through the valve. The amount of hydraulic fluid flowing through the valve controls a force generated by the door closer assembly on a door. A first sensor measures an angular position of the door, and a second sensor measures an angular position of the valve. The angular position of the valve determines the amount of hydraulic fluid flowing through the valve. A controller controls the adjustment of the valve based on the angular position of the door and the angular position of the valve.