Abstract: A stator core includes slots, and further includes a first cutout portion, two second cutout portions and two third cutout portions are formed on the outer circumference of the stator core. A center of the first cutout portion in the circumferential direction and a center of each second cutout portion in the circumferential direction are at an angle of 90 degrees with respect to the center axis. The two third cutout portions are formed on both sides of a straight line passing though the center axis and the center of the first cutout portion. A first contact portion in contact with a shell is formed between the two third cutout portions. When D1 represents a minimum distance from the first contact portion to its closes slot, and D2 represents a minimum distance from each third cutout portion to its closet slot, 1.00?D1/D2?1.60 is satisfied.

Abstract: A rotor core has a magnet insertion hole. The magnet insertion hole has a first hole portion located at a center thereof, and two second hole portions extending from both ends of the first hole portion toward the outer circumference of the rotor core. A first permanent magnet is disposed in the first hole portion, and a second permanent magnet is disposed in each second hole portion. The rotor core has a first slit formed between each second hole portion and the magnetic pole center line and having a length in the circumferential direction, and a second slit formed between the first slit and the magnetic pole center line and having a length in the radial direction. The shortest distance C [mm] from the first slit to the magnet insertion hole and the shortest distance S [mm] from the first slit to the outer circumference satisfy S??0.7517 C2+0.2021 C+1.1395.

Abstract: A rotor includes a rotor core, a first permanent magnet that is W1 mm long in a longitudinal direction, and a second permanent magnet that is W1 mm long in a longitudinal direction. The rotor core includes a first magnet insertion hole, a second magnet insertion hole, and a center lib. The first magnet insertion hole includes a first outside opening part having a radius of curvature of R1 mm, and a first inside opening part having a radius of curvature of R2 mm. The second magnet insertion hole includes a second outside opening part having a radius of curvature of R1 mm, and a second inside opening part having a radius of curvature of R2 mm. The rotor satisfies R1>R2 and 0<(R1+R2)/W1<0.082.

Abstract: An electric motor includes: a stator including a first stator core, a second stator core, and a slot in which a stator winding is disposed, and a rotor including a first rotor core facing a first stator core in a radial direction and a second stator core facing the second stator core in the radial direction. The first stator core and the second stator core are laminated in an axial direction. The stator includes a depression formed in a position facing the slot and not touching the stator winding. A volume of the first rotor core is smaller than a volume of the second rotor core.

Abstract: An electric motor includes a rotor, a stator, and a connection switching unit. The stator includes a stator core including 6×n (n is an integer equal to or larger than 1) slots, and three-phase coils forming 2×n magnetic poles. The connection switching unit switches a connection state of the three-phase coils between a first connection state and a second connection state. The three-phase coils include 2×n U-phase coils, 2×n V-phase coils, and 2×n W-phase coils in a coil end. Each coil of the three-phase coils is disposed in two slots across one slot on one end side of the stator core.

Abstract: A rotor includes a rotor core, a first permanent magnet that is W1 mm long in a longitudinal direction, and a second permanent magnet that is W1 mm long in a longitudinal direction. The rotor core includes a first magnet insertion hole, a second magnet insertion hole, and a center lib. The first magnet insertion hole includes a first outside opening part having a radius of curvature of R1 mm, and a first inside opening part having a radius of curvature of R2 mm. The second magnet insertion hole includes a second outside opening part having a radius of curvature of R1 mm, and a second inside opening part having a radius of curvature of R2 mm. The rotor satisfies R1>R2 and 0<(R1+R2)/W1<0.082.

Abstract: A method for producing an electric motor includes: connecting a first phase coil of three-phase coils to a positive side of a source of electrical power for magnetizing; passing an electric current through the three-phase coils in a state where a center of a magnetic pole of a rotor is rotated a first angle with respect to a center of a magnetic pole of the first phase coil; switching a connection with the positive side of the source of electrical power from the first phase coil to a second phase coil; and passing an electric current through the three-phase coils in a state where the center of the magnetic pole of the rotor is rotated a second angle with respect to a center of a magnetic pole of the second phase coil.

Abstract: An electric motor includes: a stator including a first stator core, a second stator core, and a slot in which a stator winding is disposed, and a rotor including a first rotor core facing a first stator core in a radial direction and a second stator core facing the second stator core in the radial direction. The first stator core and the second stator core are laminated in an axial direction. The stator includes a depression formed in a position facing the slot and not touching the stator winding. A volume of the first rotor core is smaller than a volume of the second rotor core.