| 主权项 |
1. An interior permanent magnet motor, comprising:
a stator; and a rotor rotatably arranged so as to be opposed to the stator, wherein the rotor comprises a rotor core having a plurality of magnet insertion holes formed therein, into which corresponding permanent magnets are respectively inserted, wherein an air gap is secured between a rotor outer peripheral surface of the rotor and a stator inner peripheral surface of the stator, wherein the stator comprises a plurality of tooth portions, wherein a tooth tip portion having both side portions expanding in a circumferential direction is formed on a distal end portion of each of the tooth portions, wherein the rotor outer peripheral surface comprises, when viewed in a cross-section orthogonal to a rotation center line:
a plurality of first arcs; anda plurality of second arcs, wherein each of the first arcs is positioned in a corresponding magnetic pole center portion on the rotor outer peripheral surface, wherein each of the second arcs is positioned in a corresponding inter-pole portion on the rotor outer peripheral surface, wherein the first arc bulges toward a radially outer side to a higher degree than the second arc so that the air gap is varied in a manner of being increased as approaching from each of the magnetic pole center portions to the adjacent inter-pole portions, wherein, when viewed in the cross-section orthogonal to the rotation center line, a hole defining portion of each of the magnet insertion holes of the rotor core on the radially outer side has a curvature of a third arc, and a hole defining portion of the each of the magnet insertion holes of the rotor core on a radially inner side has a curvature of a fourth arc, and wherein an opening angle of the tooth tip portion, an opening angle of the first arc, and an opening angle of the third arc coincide with each other. |
