Patent ID: 6246228
Filing Date: 2001-06-12
Classification: G01B

Abstract:
A position sensor for sensing a position of an armature in an actuator, the armature having at least one armature winding, the position sensor comprising:excitation wave generating means for generating an excitation wave;at least one sensor excitation winding for generating an excitation magnetic field from the excitation wave and for applying the excitation magnetic field to the at least one armature winding to cause the at least one armature winding to generate a response signal;detecting means, connected to the at least one armature winding, for detecting the response signal in the armature winding; anddemodulating means for determining the position of the armature from the response signal detected by the detecting means, andat least one sensor winding having a first sensor excitation winding disposed above the armature and a second sensor excitation winding disposed below the armature the first and second sensor excitation windings causing z components of the response signal which cancel out so that the response signal is z-invariant.