| 摘要 |
<p>A rotational position detector is mounted both on the rotational shaft of a rotor (11) and on the output shaft of a speed-reduction gear section (20). If the detected value of the rotational position (θm) of the rotor (11) is 1024 pulses/revolution and the speed-reduction ratio (Gn) is 4, then that of the speed-reduction gear section (20) is 1024 × 4 = 4096 pulses/revolution of the output shaft; thus, the absolute rotational position can be detected with high accuracy. Since the integer portion (N) of θg × Gn/2 π is the number of revolutions the rotor (11) makes when the output shaft has rotated by θg, the absolute rotational position of the rotor (11) can be calculated by θm + N × 2 π. Therefore, the position of the rotational shaft can be detected with high accuracy without being influenced by temperature change.</p> |
