Three-phase motor

A three-phase motor having a stator formed by inserting winding coils of three phases of U-phase, V-phase and W-phase into slots provided on an inner circumferential surface of a stator core,

• wherein the winding coil of each phase has plural unipolar coils formed by winding electric wires in plural turns, a connecting wire for connecting the unipolar coils, and a pair of lead parts formed by leading out the electric wires from unipolar coils situated at both ends of each of the plurality of winding coils, and each of the unipolar coils includes a pair of insertion parts to be inserted into the slots and a pair of coil end parts connecting the pair of insertion parts, and
• with respect to average circumferential lengths of the unipolar coils in the winding coils of the three phases, the average circumferential length in the unipolar coils of V-phase is shorter than the average circumferential length in the unipolar coils of U-phase, and the average circumferential length in the unipolar coils of W-phase is shorter than the average circumferential length in the unipolar coils of V-phase, and
• the pair of insertion parts of the unipolar coils of U-phase are inserted in the slots and the pair of coil end parts of the winding coils of U-phase protrude from end parts in an axial direction of the stator core, and
• the pair of insertion parts of the unipolar coils of V-phase are offset from the unipolar coils of U-phase by a predetermined number of slots in a first direction, which is one circumferential direction of the stator core, as they are inserted in the slots, and the pair of coil end parts of the unipolar coils of V-phase are partly superposed on an inner circumferential side of the pair of coil end parts of the unipolar coils of U-phase, and
• the pair of insertion parts of the unipolar coils coil of W-phase are offset from the unipolar coils of V-phase by a predetermined number of slots in the first direction of the stator core as they are inserted in the slots, and the pair of coil end parts of the unipolar coils of W-phase are partly superposed on an inner circumferential side of the pair of coil end parts of the unipolar coils of V-phase.