| 摘要 |
A rotor (12) is provided with a circular rotor core (26) and a plurality of &thetas; magnets (28). The &thetas; magnets (28) are housed in magnet housing sections (26b) so that the same magnetic poles as the magnetic poles of adjacent magnets are opposite each other in the circumferential direction of the rotor core. When S1 [mm2] is the area of the surface having the magnetic pole of the &thetas; magnets (28), S2 [mm2] is the area of the outer peripheral surface of the rotor core, P is the number of magnetic poles of the rotor, Dr [mm] is the maximum outer diameter of the rotor core, and Lm [mm] is the thickness of a plate-like magnet in the circumferential direction of the rotor core, the rotor satisfies S1 > S2 / P... formula (1), and 0.665 × 10-4 × P2 − 0.28 × 10-2 × P + 0.577 × 10-1 < (Lm / Dr) < 3.38 × 10-4 × P2 −1.86 × 10-2 × 3 + 3.36 × 10-1... formula (2). |
