Patent ID: 7986139

Claim:
A position sensor comprising: a coil section including a plurality of layers of flat coils that are stacked on each other and connected in series with each other to form a single coil pole, the coil pole being energized by an A.C. signal; and a magnetism-responsive member disposed to be opposed to the coil pole in a non-contact manner, wherein a relative position between said coil section and said magnetism-responsive member is caused to vary by displacing at least one of said coil section and said magnetism-responsive member in response to a position to be detected, correspondency, to said coil section, of said magnetism-responsive member varies in response to variation in the relative position, to cause impedance variation in the coil pole, and a position detection signal is provided on the basis of an output signal, responsive to the impedance variation, taken out from the coil pole, wherein said coil section includes a plurality of circuit boards that are stacked on each other, and the flat coils are respectively provided on surfaces of the circuit boards, and wherein a plurality of the layered flat coils are disposed in a horizontal arrangement per layer in corresponding relation to the one coil pole, and outputs of the flat coils are added together to provide an output signal of the one coil pole.