US 11,888,368 B2
Rotor, electric motor, air blower, air conditioner, and method for fabricating rotor
Takanori Watanabe, Tokyo (JP); and Hiroki Aso, Tokyo (JP)
Assigned to Mitsubishi Electric Corporation, Tokyo (JP)
Appl. No. 17/413,353
Filed by Mitsubishi Electric Corporation, Tokyo (JP)
PCT Filed Dec. 17, 2018, PCT No. PCT/JP2018/046344
§ 371(c)(1), (2) Date Jun. 11, 2021,
PCT Pub. No. WO2020/129123, PCT Pub. Date Jun. 25, 2020.
Prior Publication US 2022/0045589 A1, Feb. 10, 2022
Int. Cl. H02K 21/16 (2006.01); H01F 41/02 (2006.01); H02K 1/2733 (2022.01); H02K 1/2746 (2022.01); H02K 1/2786 (2022.01); H02K 7/14 (2006.01); H02K 15/03 (2006.01); H02K 1/278 (2022.01)
CPC H02K 21/16 (2013.01) [H01F 41/028 (2013.01); H02K 1/278 (2013.01); H02K 1/2733 (2013.01); H02K 1/2746 (2013.01); H02K 1/2786 (2013.01); H02K 7/14 (2013.01); H02K 15/03 (2013.01); H02K 2213/03 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A rotor having 2n (n is a natural number) magnetic poles, comprising:
at least one first permanent magnet forming part of an outer peripheral surface of the rotor and magnetized to have polar anisotropy; and
at least one second permanent magnet that is a different type from the at least one first permanent magnet, is adjacent to the at least one first permanent magnet in a circumferential direction of the rotor, has lower magnetic force than magnetic force of the at least one first permanent magnet, and is magnetized to have polar anisotropy, and
the at least one second permanent magnet is a single integral ring-shaped magnet,
a length of the at least one first permanent magnet in an axial direction of the rotor is longest at a center of the at least one first permanent magnet in the circumferential direction of the rotor, and
the length of the at least one first permanent magnet in the axial direction of the rotor gradually decreases with being away from the center along the circumferential direction.