Patent ID: 11962192
Assignee: MITSUBISHI ELECTRIC CORPORATION
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H  F | IPC F  H

Claim 15:
16. An electric motor comprising:
a rotor including two permanent magnets, a first rotor core having a first electrical steel sheet, and a second rotor core having a second electrical steel sheet, the rotor having a magnetic pole part formed by the two permanent magnets; and
a stator including a stator core and a winding fixed to the stator core, the stator being disposed outside the rotor, wherein
the first electrical steel sheet is located outside the stator core in an axial direction of the rotor,
the first electrical steel sheet includes
a first left flux barrier part and a first right flux barrier part respectively provided on both sides of the magnetic pole part in a circumferential direction of the rotor, in a plane perpendicular to the axial direction,
a first left bridge provided between the first left flux barrier part and an outer peripheral surface of the first rotor core,
a first right bridge provided between the first right flux barrier part and the outer peripheral surface of the first rotor core, and
a first center bridge provided between the two permanent magnets,
the second electrical steel sheet includes
a second left flux barrier part and a second right flux barrier part respectively provided on both sides of the magnetic pole part in the circumferential direction in the plane, and
a bridge provided between the second right flux barrier part and an outer edge of the second rotor core, the second right flux barrier part being provided on an upstream side in a rotation direction of the rotor,
the second rotor core includes a plurality of outer peripheral surfaces that are separated from one another, and
the electric motor satisfies
BR1>BR2,
where BR1 is a minimum width of the first right bridge in the plane and BR2 is a minimum width of the bridge of the second electrical steel sheet in the plane.