| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a low-vibration and low-noise permanent magnet embedded type electric motor having a favorable demagnetization characteristic. <P>SOLUTION: A permanent magnet embedded type electric motor according to the present invention includes: a stator and a rotor arranged on an inner peripheral side of the stator with a gap therebetween. The rotor includes: a rotor core produced by punching out a magnetic steel sheet in a predetermined shape to obtain pieces of the magnetic steel sheet and laminating a predetermined number of the pieces; a plurality of magnet insertion holes formed along an outer peripheral portion of the rotor core; permanent magnets inserted into the magnet insertion holes; a plurality of slits formed on an outer peripheral side of the magnet insertion holes; and end plates arranged for both end faces of the rotor core in a direction of the laminating, wherein in each set of the plurality of slits formed for one of the permanent magnets, each slit for suppression of demagnetization arranged on an extended line extending from an end face of the permanent magnet in a circumferential direction toward an outer peripheral side of the rotor core has a width in the circumferential direction that is wider than those of other slits formed within a width of the permanent magnet. <P>COPYRIGHT: (C)2012,JPO&INPIT |
