| 摘要 |
PURPOSE:To self-start to rotate a brushless motor in the prescribed direction without particular part by forming a projection on the surface of a rotor yoke oppositely to an armature, and securing a magnet having a recess corresponding to the projection to the yoke. CONSTITUTION:A projection 24a is formed on the surface of a rotor yoke 24 oppositely to a stator armature 20 in a disc-type brushless motor 11 having a rotor which rotates relatively oppositely to the armature 20. A recess corresponding to the projection 24a of the yoke 24 is formed on a rotor magnet 21 secured to the yoke 24, and a rotor magnet 21 is so secured to the yoke 24 so than an air gap length between the rotor and the armature 20 becomes uniform. Thus, it can be self-started even without a magnetic unit for generating a cogging and can control at a low speed. |
