Rotor for permanent-magnet-embedded electric motor, electric motor including the rotor, compressor including the electric motor, and air conditioner including the compressor

A rotor for a permanent-magnet-embedded electric motor, rotatably held on an inner peripheral face of a stator, the rotor comprising:

• a rotor core formed by laminating a plurality of electromagnetic steel plates;
• a plurality of magnet insertion holes formed along an outer periphery in a circumferential direction of the rotor core;
• tabular permanent magnets inserted into the magnet insertion holes with alternating polarities, to form a plurality of magnetic poles;
• and
• elongated slit holes each formed in the vicinity of opposite ends of the magnetic pole between an outer peripheral face of the rotor core and the magnet insertion hole wherein
• an inclination of a longitudinal axis of each of the slit holes opened towards a center of the magnetic pole with respect to a width direction of the permanent magnet is set to be in a range from 0 to 30 degrees, and a magnetic path between the outer peripheral face of the rotor core and the slit hole extends toward a center side of the magnetic pole.