MOTOR

Abstract

A motor (10) has an annular stator (12) with a plurality of teeth (16) extending towards a central axis (L) and arranged in a rotational direction relative to each other, and windings (18) wound on the teeth. The motor also has a rotor (13) with a rotor core (22) rotatably mounted within the stator and a plurality of permanent magnets (23) provided in the rotor core and arranged in a rotational direction relative to each other. The rotor further comprises a plurality of magnetic pole sections (22b) formed by the plurality of permanent magnets on a surface of the rotor core facing the stator and aligned with each other in the rotational direction. At least some of the magnetic pole sections each have a groove (22c) radially recessed inwards.In each of the at least some magnetic pole sections, the groove is formed symmetrically in the direction of rotation with respect to a magnetic pole center, which is a center of rotation of the magnetic pole section. Furthermore, the motor is configured such that the relationship 0.12 < Wg / (360 / P) < 0.31 is satisfied, where Wg is the angle of the groove width at a radially outer end thereof and P is the number of magnetic pole sections.

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