| 摘要 |
<p>A brushless motor comprising a four-pole permanent-magnet rotor 11 and a four-pole stator. The stator comprises two C shaped stator elements 15,16 arranged on opposite sides of the rotor. Each stator element comprises a core having a back 22 and two arms 23,24 that extend from opposite ends of the back, and at least one coil 20,21 wound about the core. The free end of each arm defines a pole tip 25, and the pole tips collectively have four-fold rotational symmetry about the rotational axis of the rotor. Chamfers 26 may be formed at the pole tips and the width of the pole sections may be greater than the width of the straight portions 28 of the arms. The gap 29 between pole tips is smaller than the separation 30 of the arms. The arrangement is easier to wind and achieves a high fill factor.</p> |
