Permanent magnet type rotating electrical machine

A permanent magnet type rotating electrical machine comprising:

• a stator;
• a rotor core having a plurality of magnet inserting holes;
• and
• a plurality of permanent magnets inserted in the magnet inserting holes and fixed to the rotor core, wherein
• the permanent magnets include a plurality of north-pole magnets each having a north pole on a side opposed to the stator and a plurality of south-pole magnets each having a south pole on a side opposed to the stator,
• each two adjacent south-pole magnets configure a first pair,
• each two adjacent north-pole magnets configure a second pair,
• the first and second pairs are fixed to the rotor core to be arranged alternately in a circumferential direction of the rotor core,
• the magnet inserting holes include south-pole magnet inserting holes that accommodate the two south-pole magnets configuring the first pair and north-pole magnet inserting holes that accommodate the two north-pole magnets configuring the second pair,
• the south-pole magnet inserting holes include a first magnet inserting hole that accommodates one of the two south-pole magnets and a second magnet inserting hole that accommodates the other one of the two south-pole magnets,
• the north-pole magnet inserting holes include a first magnet inserting hole that accommodates one of the two north-pole magnets and a second magnet inserting hole that accommodates the other one of the two north-pole magnets,
• in the first and second magnet inserting holes of the south-pole magnet inserting holes, the first magnet inserting hole has a first end opposed to the second magnet inserting hole, and the second magnet inserting hole has a second end opposed to the first magnet inserting hole,
• in the first and second magnet inserting holes of the north-pole magnet inserting holes, the first magnet inserting hole has a first end opposed to the second magnet inserting hole, and the second magnet inserting hole has a second end opposed to the first magnet inserting hole,
• the first magnet inserting hole and the second magnet inserting hole of the south-pole magnet inserting holes are configured identically with the first magnet inserting hole and the second magnet inserting hole of the north-pole magnet inserting holes, respectively,
• each first magnet inserting hole and the corresponding second magnet inserting hole are spaced apart such that a partition wall is defined between the first end of the first magnet inserting hole and the second end of the second magnet inserting hole,
• in a section of each of the first and second ends on an outer side in a radial direction of the rotor core, a bulging portion is arranged between a surface of the partition wall and a surface extending along the permanent magnet in the first magnet inserting hole or the second magnet inserting hole,
• the bulging portion has a first curved surface continuous with the surface of the partition wall and a second curved surface continuous with the surface extending along the permanent magnet in the first magnet inserting hole or the second magnet inserting hole, and
• the curvature of the first curved surface is smaller than the curvature of the second curved surface.