| 摘要 |
A brushless motor 1 comprises a rotor 3 having a magnet 2 and a stator 4 having a stator core 8 . The stator core 8 has teeth 11 provided at the front ends thereof with auxiliary grooves to realize a pseudo-multi-slot arrangement. The magnet 2 has an axial length of L<SUB>M </SUB>while the stator core 8 has an axial length of L<SUB>S</SUB>, L<SUB>S </SUB>being greater than L<SUB>M </SUB>(L<SUB>S</SUB>>L<SUB>M</SUB>). The stator core 8 is provided at the opposite ends thereof with respective overhanging portions 15 that are not vis-à-vis the magnet 2 . As a result, the magnetic flux is prevented from flowing into the stator core 8 through the axial end faces 8 a thereof. In other words, the magnetic flux mostly flows into the stator core 8 through the front ends of the teeth. As a result, the pseudo-multi-slot effect produced by the auxiliary grooves is efficiently boosted to reduce cogging and other problems.
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