| 摘要 |
PROBLEM TO BE SOLVED: To provide an embedded magnet type motor that is able to improve the magnetism decrease resistance of a permanent magnet 7 arranged on the innermost diameter side of a rotor.SOLUTION: In a rotor core 6, three-layer slits 8 (a first slit 8a, second slit 8b, third slit 8c in that order from the innermost diameter side of a rotor toward the outer-diameter side) are formed for each one pole in a rotor radial direction, and a permanent magnet 7 is inserted in each slit 8. The width (magnetic path width A) of a first magnetic path 6a provided between the first slit 8a and the second slit 8b is made narrower than the width (magnetic path width B) of the second magnetic path 6b provided between the second slit 8b and the third slit 8c. Making the magnetic path width A narrower than the magnetic path width B makes it possible to restrict a magnetic flux flowing into the first magnetic path 6a from the stator, in comparison with a configuration where the magnetic path width A is equal to the magnetic path width B. By virtue of this, since reverse magnetic field applied to the central part of the permanent magnet 7 on the innermost diameter side of the rotor, inserted into the first slit 8a, decreases and, therefore, the magnetism decrease resistance of the magnet central part can be improved.SELECTED DRAWING: Figure 2 |
