Patent ID: 7538544

Claim:
An apparatus for determining a part position of a movable part, comprising: a transmitter coil, the transmitter coil generating electromagnetic radiation when the transmitter coil is excited by a source of electrical energy; a receiver coil disposed in proximity to the transmitter coil, the receiver coil generating a receiver signal when the transmitter coil is excited due to an inductive coupling between the receiver coil and the transmitter coil; and a coupler element overlying at least a portion of said transmitter coil and at least a portion of said receiver coil, the coupler element being moveable and having a coupler element position correlated with the part position, the coupler element modifying the inductive coupling between the transmitter coil and the receiver coil so that the receiver signal is correlated with the part position, wherein the receiver coil includes a first loop configuration and a second loop configuration, the first loop configuration and second loop configuration having opposite winding directions, and wherein the inductive coupling between the transmitter coil and the first loop configuration generates a first signal, the inductive coupling between the transmitter coil and the second loop configuration generates a second signal, the receiver signal being a combination of the first signal and the second signal.