Patent ID: 9689713
Date: 2017-06-27
CPC Classifications: G01D

Claim:
1. A rotation angle detection apparatus comprising: three or more sensing portions; and a controller, wherein each of the three or more sensing portions includes a main circuit unit and a subsidiary circuit unit, the main circuit unit is provided by a full bridge circuit and outputs a main positive signal and a main negative signal as output signals, the main positive signal corresponds to a rotating magnetic field which changes corresponding to a rotation of a detection target, and the main negative signal has an inverted polarity relative to a polarity of the main positive signal, the subsidiary circuit unit is provided by a full bridge circuit and outputs a subsidiary positive signal and a subsidiary negative signal as output signals, the subsidiary positive signal corresponds to the rotating magnetic field which changes corresponding to the rotation of the detection target, the subsidiary positive signal has a different phase from the main positive signal, and the subsidiary negative signal has an inverted polarity relative to a polarity of the subsidiary positive signal, the controller includes an angle calculator and an abnormality monitoring unit, the angle calculator calculates a rotation angle of the detection target based on a main signal and a subsidiary signal, the main signal corresponds to at least one of the main positive signal or the main negative signal outputted from the main circuit unit, and the subsidiary signal corresponds to at least one of the subsidiary positive signal or the subsidiary negative signal outputted from the subsidiary circuit unit, and the abnormality monitoring unit monitors an abnormality occurrence by comparing the corresponding output signals outputted from the three or more sensing portions.