US Patent 7232111 Control arrangement for an automatic residential faucet

A hands-free faucet comprises a spout, a valve, a position sensitive device, and a logical control. The position sensitive device is positioned on the user's side of the spout, and has a trigger zone and an extended zone, each defined in part by a distance range from the position sensitive device. The logical control comprises a manual mode, wherein the position sensitive device is deactivated and the valve remains open, and a hands-free mode, wherein the valve is opened when the position sensitive device detects an object within the trigger zone, and wherein the valve is closed only when the position sensitive device does not detect an object within the trigger zone and does not detect an object that is moving within the extended zone.