Axial gap type brushless motor

1. An axial gap type brushless motor, comprising:

a stator that includes a coil; and

a rotor that includes a permanent magnet, the rotor being spaced apart from the stator in an axial direction,

wherein the coil is formed of a band-like wire that is spirally wound such that a width direction of the band-like wire generally coincides with a direction of a magnetic flux generated by the permanent magnet of the rotor,

wherein a plurality of the permanent magnets are arranged in a peripheral direction, and

wherein the rotor includes

conductors that extend in a radial direction between the permanent magnets arranged in the peripheral direction, and

short-circuiting rings that short-circuit ends of the conductors on inner and outer peripheral sides of the rotor.

2. The axial gap type brushless motor according to claim 1 , further comprising:

a thermally conductive material that fills a gap between the coil and a yoke on the stator side, the stator being a stator on which the coil is mounted.

3. The axial gap type brushless motor according to claim 1 ,

wherein the rotor further includes a plurality of magnetic members periodically disposed in a peripheral direction at least on an outer peripheral side of the permanent magnet.

4. The axial gap type brushless motor according to claim 1 ,

wherein the conductors and the short-circuiting rings are included in a frame, the frame being secured to a rotating shaft, the permanent magnets being fitted into the frame.

5. The axial gap type brushless motor according to claim 1 ,

wherein the coils are each supplied with a coil current in a corresponding one of nine phases.

6. The axial gap type brushless motor according to claim 1 ,

wherein a pair of the stators are provided on both sides of the rotor.

7. The axial gap type brushless motor according to claim 1 ,

wherein a plurality of the coils are arranged in a radial direction.

8. The axial gap type brushless motor according to claim 1 ,

wherein a yoke of the stator is formed by molding a soft magnetic powder, the yoke having a magnetic isotropy.

9. The axial gap type brushless motor according to claim 8 ,

wherein particles of the soft magnetic powder are covered with an electrically insulating layer.

10. The axial gap type brushless motor according to claim 1 ,

wherein a yoke of the stator is formed of a band-like soft magnetic material that is wound such that a width direction of the soft magnetic material extends in a direction in which a rotating shaft of the rotor extends.

11. The axial gap type brushless motor according to claim 10 ,

wherein an insulating layer is further provided between turns of the wound soft magnetic material.

12. The axial gap type brushless motor according to claim 1 ,

wherein the band-like wire further includes a second soft magnetic material disposed on one of side surfaces of the band-like wire, the one side surface being perpendicular to the axial direction.

13. The axial gap type brushless motor according to claim 12 ,

wherein the coil has a linear portion in a peripheral direction, and the second soft magnetic material is arranged in the linear portion.

14. The axial gap type brushless motor according to claim 12 ,

wherein a thickness of the second soft magnetic material in a direction perpendicular to the axial direction is equal to or smaller than a skin thickness in accordance with a frequency of an alternating current power supplied to the coil.

15. The axial gap type brushless motor according to claim 12 ,

wherein the band-like wire is covered with the second soft magnetic material.