| 摘要 |
<p>PROBLEM TO BE SOLVED: To reduce the influence of a noise, and to improve detection accuracy or stability.SOLUTION: A rotation angle detection device 1 includes: a distance detection part 6 for detecting a distance between itself and a rotary body 2 or a passive member 3; a distance detected surface 4 for continuously changing a distance between itself and the distance detection part 6 in accordance with the rotation of the rotary body 2; and an angle specification part 7 for specifying the absolute rotation angle of the rotary body 2 on the basis of the distance detected by the distance detection part 6. The angle specification part 7 for specifying the absolute rotation angle of the rotary body 2 on the basis of the inductance change of a plurality of detection coils 9 arranged at predetermined intervals in the rotation direction of the distance detected surface 4 is connected to AC exciting circuits 8 for generating phase shifts in AC excitation waves in accordance with the inductance change of the detection coils 9 while AC-exciting the detection coils 9, and configured to temporally accumulate the phase shifts of the AC excitation waves, and to specify the absolute rotation angle of the rotary body 2 on the basis of the accumulated phase shifts.</p> |
