Patent ID: 9024626
Filing Date: 2015-05-05
Classification: G01B,G01D

Abstract:
1. An angle detecting device comprising: a rotation member provided with a magnet portion which generates a magnetic field having polarities arranged alternately in a circumferential direction; a case having a bearing on which the rotation member is rotatably supported; an angle calculating means for detecting magnetic field components of the magnetic field in a plurality of different directions and calculating a rotation angle of the rotation member based on the detected magnetic field components; and an elastic member which biases the rotation member so that the rotation member is rotated, keeping a constant inclined direction relative to a central axis line of the bearing or biases the rotation member so that a phase difference between a rotation phase of the rotation member and a rotation phase of the bearing rotating about the central axis line thereof with the inclined direction relative to the rotation member is kept constant regardless of a change of the rotation angle of the rotation member, wherein the angle calculating means comprises a first pair of magnetic sensors arranged in a line perpendicular to the central axis line and a second pair of magnetic sensors arranged in a line parallel to the central axis line.