Motor and its rotor and magnetic core for rotor having arrangement of non-magnetic portions

摘要

A first non-magnetic portion, a second non-magnetic portion, and a third non-magnetic portion are arranged around an axis, from an end toward the center of a permanent magnet burying hole. A fourth non-magnetic portion is further provided between the second non-magnetic portion and the third non-magnetic portion. 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. The position between the third non-magnetic portion and the fourth non-magnetic portion is expressed by a second angle, 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. 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.

主权项

1. A magnetic core for a rotor, said magnetic core comprising:
permanent magnet burying holes arranged around an axis; and a first non-magnetic portion, a second non-magnetic portion, and a third non-magnetic portion arranged around the axis from an end toward a center of each said permanent magnet burying hole, wherein a value of an angle around said axis with reference to a position between adjacent said permanent magnet burying holes, translated from a position of an end of said third non-magnetic portion that is located closer to a center of corresponding said permanent magnet burying hole, is a value obtained by dividing 360 degrees by a value that is three times the number of said permanent magnet burying holes.