As shown in FIG. 30, the stator 701 is fixed to the housing 703, and the outer peripheral surface of the stator 701 faces the housing 703. The stator 701 includes an annular stator core 705 and a stator winding 706 wound around the stator core 705. The stator core 705 is formed by a plurality of annular electromagnetic steel sheets stacked in the axial direction α, so that the stator core 705 has a tubular shape as a whole. The stator winding 706 includes a plurality of conductor segments. The stator winding 706 is formed by connecting these conductor segments to each other in a state of being mounted on the stator core 705. The conductor segment includes a long conductor and an insulating coating covering the outer peripheral surface of the conductor. The insulating film is formed of a resin material such as a polyimide resin. The stator core 705 is provided with a plurality of slots penetrating in the stator core 705 in the axial direction α. The conductor segments are inserted into the slots, thereby to form the stator core 705.
The rotor 702 has a rotor hole 702a that is coaxial with the rotor 702 and extends along the center line CL2. Thus, the rotor 702 has an annular shape due to the rotor hole 702a. The rotor 702 includes a plurality of permanent magnets, and the outer peripheral surface of the rotor 702 is formed by these permanent magnets. In the rotor 702, the plurality of permanent magnets form a plurality of magnetic poles having alternately different polarities in the circumferential direction γ. The outer peripheral surface of the rotor 702 is separated from the inner peripheral surface of the stator 701 in a radially inward direction.
