Patent ID: 8148973
Filing Date: 2012-04-03
Classification: G01D,H02K

Abstract:
1. A magnetic resolver comprising: a stator portion which includes an annular plate having, on a side thereof, a plurality of columnar cores; a coil portion disposed around each of the columnar cores; and an annular rotor which has an outer periphery having a sinusoidal profile line that rotates in a plane that is parallel to top faces of the columnar cores around a rotation axis that passes through the center of the annular plate, wherein a radius of the rotor varies according to a sine function, an amplitude of the sine function being substantially equal to a radius of the columnar cores, wherein the columnar cores are radially disposed between a maximum radius and a minimum radius of the rotor, wherein an area by which a top face of the columnar core and the annular rotor overlap when viewed from above, varies as a rotation angle of the annular rotor relative to the stator portion varies, and wherein when one of the columnar cores is disposed between two crests of the profile line of the rotor when viewed from above, a gap is formed between the one of the columnar cores and a trough of the profile line.