| 摘要 |
PURPOSE:To provide a brushless motor that changes excitation layers at good timing, by reducing the influence caused by the variation in position-sensor sensitivity. CONSTITUTION:A brushless motor has a magnetic-sensitive position sensor 25 put in an anti-thrust direction of a rotor body 17. The rotor body 17 is made up of a permanent magnet 20 between a pair of rotor yokes 18 and 19. The rotor yokes 18 and 19 includes a base part 21 that overlaps with the permanent magnet 20, and a salient-pole opposing member 22 located opposite and near to the top of salient poles 8 to 13, which are put in a row and projected at right angles to a peripheral part 21a of the base part 21. At the same time, the salient-pole opposing member 22 is so formed that both ends of projected faces, which are opposite to the position sensor 25, are more projected than the other middle part to the position sensor 25, while both ends of an opposing member base part 21a in the base part 21 are placed opposite to the position sensor 25 and more projected than the other middle part to the position sensor 25. |
