Patent ID: 8669760

Claim:
An angle detection system comprising: a stator including a plurality of salient pole portions formed on a flat sheet made of a magnetic material and raised by bending, each salient pole portion constitutes a winding magnetic core on which a winding member for excitation and a winding member for detection are mounted; and a rotor made of a magnetic material and is rotatable relative to the stator such that a gap permeance between the rotor and each salient portion is configured to be changed due to the rotation thereof about a rotation axis thereof, wherein the angle detection system is an inner-rotor-type angle detection system in which the gap permeance between an outer side of the rotor and said each salient pole portion is configured to be changed due to the rotation of the rotor, wherein a smallest inner diameter of the flat sheet after bending is an inner diameter of the flat sheet at the respective salient pole portions, such that undesired projections are not formed on an inner side of the flat sheet.