| 摘要 |
PURPOSE:To improve the characteristics and efficiency of a motor by arranging an insensitive zone correcting magnet in the vicinity of a Hall element for detecting the position of a rotor, thereby eliminating the influence of the insensitive zone of a magnetic flux distribution which is acted on the Hall element. CONSTITUTION:An insensitive zone correcting magnet 7 is arranged at the rotational shaft 3 side in the vicinity of a Hall element H on a printed board 6. The position of a rotor RT is detected by a Hall element H. The magnet 7 always passes a magnetic flux in the Hall element H. In this manner, the insufficient amount of the output voltage due to the insensitive zone of a magnetic flux distribution which is acted on the Hall element H is compensated, and the output voltage of the Hall element H becomes the waveform inverted in polarity at the switching part of the permanent magnet 1. |
