Patent ID: 11894726
Assignee: MITSUBISHI ELECTRIC CORPORATION
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H | IPC H

Claim 8:
9. A rotating electric machine, comprising:
a stator including:
a stator core in which a plurality of teeth radially projecting from an annular core back are arrayed in a circumferential direction; and
a stator coil; and

a rotor including:
a rotor core arranged coaxially with the stator core with a gap being secured between the stator core and the rotor core; and
a plurality of permanent magnets which are embedded in the rotor core, and are arranged in the circumferential direction,

wherein the rotor core has:
a gap surface facing the gap;
a plurality of magnet insertion holes into which the plurality of permanent magnets are inserted;
a slit which is formed in a core region between the gap surface and, among the plurality of magnet insertion holes, a magnet insertion hole into which a permanent magnet forming one magnetic pole is inserted, and divides the core region into a plurality of divided core regions in the circumferential direction; and
a cutout formed by denting the gap surface of, among the plurality of divided core regions, a divided core region positioned at a head in a direction opposite to a direction of a circumferential force acting on the rotor when the stator coil is energized,

wherein, in a plane orthogonal to an axial direction of the rotor core, a shortest distance between a stator core imaginary gap surface which is a perfect circle having an axial center of the rotor core as a center, and is in contact with distal end surfaces of the plurality of teeth facing the gap, and a bottom point of the cutout is longer than a shortest distance between the stator core imaginary gap surface and each of two intersections between the cutout and the gap surface,
wherein a shortest position of the cutout with respect to the magnet insertion hole into which the permanent magnet forming one magnetic pole is inserted in a region of the rotor core into which a reluctance magnetic flux flows from the stator core is an intersection between the cutout and the gap surface, and
wherein a bottom point of the cutout is closer to, of the two intersections between the cutout and the gap surface, an intersection which is different from the intersection between the cutout and the gap surface at the shortest position of the cutout with respect to the magnet insertion hole, and is positioned in the direction of the circumferential force acting on the rotor when the stator coil is energized.