Rotational position detection device

A rotational position detection device comprising a stator section including winding means for producing a secondary output signal, said winding means being excited by one or more primary AC signals, and a rotor section disposed in such a manner that it is capable of performing relative rotational displacement with respect to said stator section,

• said winding means comprising a plurality of primary windings and secondary winding means, said respective primary windings being exited by primary AC signals which are shifted in phase from each other, and wherein signals derived by phase shifting said primary AC signals in response to the rotational position of said rotor section are produced from said secondary winding means,
• said rotor section comprising an electrically conductive substance portion provided in a predetermined pattern, wherein the conductive substance portion changes its position relative to the winding means in conjunction with rotational displacement of the rotor section and an eddy current corresponding to a relative rotational position of said rotor section with respect to said stator section flows in said electrically conductive substance portion and the secondary output signal is produced by said winding means, wherein the pattern of the conductive substance portion is configured such that the secondary output signal varies in correspondence with the relative rotational position of the conductive substance pattern of the rotor with respect to the stator section, the secondary output signal thereby being indicative of the rotor position at every rotational position of the rotor.