| 摘要 |
PROBLEM TO BE SOLVED: To provide an absolute angle detector detecting an absolute angle of a rotating body with high accuracy even if deviation occurs in changing positions of an arctangent signal found from a sine signal and a cosine signal outputted from a magnetic sensor. SOLUTION: The magnetic sensor 11 outputs respective signals, sinθ, cosθ, -sinθ, and -cosθ, according to changes in the direction of a magnetic field corresponding to a rotation angleθof a rotary magnet 10 rotating in conjunction with the rotation of a rotating body A. First and second tan<SP>-1</SP>θsignals with their phases deviated from each other by 1/4 cycles of respective output signals, are generated from the respective output signals of the magnetic sensor. A saw-toothed signal not using the vicinity of the changing positions of these two tan<SP>-1</SP>θsignals is generated from these two tan<SP>-1</SP>θsignals to detect the absolute angle within one rotation of the rotating body A based on this saw-toothed signal. COPYRIGHT: (C)2008,JPO&INPIT
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