US Patent 9315976 Capacitive coupling arrangement for a faucet

A faucet includes a spout and a manual handle that controls a manual valve located in a passageway that conducts fluid flow through the spout. An electrically operable valve is also located within the passageway. The faucet also includes an insulator located between the spout and the manual handle so that the spout is electrically isolated from the manual handle, a first touch sensor on the manual valve handle, a second touch sensor on the spout, and a capacitive sensor directly coupled to one of the first and second touch sensors and capacitively coupled to the other of the first and second touch sensors. The faucet further includes a controller coupled to the capacitive sensor. The controller monitors an output signal from the capacitive sensor to detect touching of the spout and the manual valve handle. The controller is also coupled to the electrically operable valve to control the electrically operable valve in response to the output signal from the capacitive sensor.