摘要 |
An object of the present invention is to improve the magnetic flux density on a rotor surface. A first non-magnetic portion (13), a second non-magnetic portion (14), and a third non-magnetic portion (16) are arranged around an axis (Q), from an end toward the center of a permanent magnet burying hole (12). A fourth non-magnetic portion (15) is further provided between the second non-magnetic portion (14) and the third non-magnetic portion (16). Angles around the axis are determined as follows with reference to a position between permanent magnet burying holes. The position between the first non-magnetic portion and the second non-magnetic portion is expressed by a first angle (¸7). The position between the third non-magnetic portion and the fourth non-magnetic portion is expressed by a second angle (2-¸7), and the second angle is twice the first angle. The end of the third non-magnetic portion located closer to the pole center is expressed by a third angle (¸3). The first angle and the third angle are values obtained by dividing 360 degrees respectively by a value that is seven times, and a value that is three times, the number of the permanent magnet burying holes. |