Patent ID: 6480007
Filing Date: 2002-11-12
Classification: G01D

Abstract:
In a position sensor for determining relative changes in position of a first member movable with respect to a second member, said sensor comprising at least a first conductor movable with one of said first and second members and a second conductor displaced from said first conductor by a gap defining a first capacitance, said second conductor being energized in response to an electrical first signal so that at least a portion of said first signal is coupled to said first conductor across said gap to induce a current in said first conductor having a current value which varies in response to relative changes in the position of said first and second members, apparatus for generating said first signal comprising in combination:a power supply furnishing a predetermined supply voltage to said sensor; a pulse generator connected to generate output pulses at a predetermined repetition rate; and a resonant circuit having a center resonant frequency included within a range of resonant frequencies which include said repetition rate, said resonant circuit being responsive to said output pulses to generate said first signal with a signal voltage greater than said supply voltage so that said current value is sufficiently large to facilitate processing.