Patent ID: 7852069

Claim:
An angle detector, comprising: an annular stator board made of a non-magnetic material; a plurality of stators provided on the annular stator board independently of one another and forming slots at constant or various intervals; a magnetic core formed protrusively on each of surfaces of the stators; stator windings formed around the magnetic cores and composed of excitation windings and output windings; a magnetic flux return path plateau provided protrusively on each of the surfaces of the stators and provided inward or outward of the stator windings; an annular rotor board provided rotatably on the magnetic flux return path plateaus and facing and remaining out of contact with the stator windings; and a gap forming board provided on an inner surface of the annular rotor board and having a board inner surface whose protrusion state changes according to a waveform, wherein the annular rotor board rotates to cause changes in a gap between each of the magnetic cores and the board inner surface of the gap forming board.