Patent ID: 7906960
Filing Date: 2011-03-15
Classification: G01B,G01D

Abstract:
1. A position sensor comprising: a transmitter coil having an outer loop portion and an inner loop portion, said transmitter coil generating electromagnetic radiation when excited by a source of electrical energy, a receiver coil disposed in close proximity with at least one of said transmitter inner and outer loop portions, said receiver coil having at least a first loop and an oppositely wound second loop, said receiver coil generating an electrical output signal when said transmitter coil is excited due to inductive coupling between said transmitter coil and said receiver coil, a movable coupler element which varies the inductive coupling between said transmitter coil and said loops of said receiver coil as a function of the position of said coupler element to thereby vary the electrical output signal from said receiver coil, a reference coil disposed between said inner and outer loop portions of said transmitter coil, said reference coil generating an electrical output reference signal when said transmitter coil is excited due to inductive coupling between said transmitter coil and said reference coil which coupling is independent of the position of said coupler element.