Patent ID: 7119470
Filing Date: 2006-10-10
Classification: H02K

Abstract:
1. A permanent magnet electric rotating machine, comprising: a stator; and a rotor arranged opposite said stator with an air gap; said rotor having a rotor core and plural permanent magnets embedded in said rotor core; plural permanent magnet insertion holes, auxiliary magnetic pole piece portions for generating a reluctance torque, and magnetic air gaps are formed in said rotor core; wherein to form magnetic pole piece portions in said rotor core, said permanent magnet insertion holes are formed in said rotor core, and said permanent magnet insertion holes are arranged with a ring-shape in an internal portion of said rotor core; said permanent magnets are inserted into said permanent magnet insertion holes alternatively with a reversed polarity, and said permanent magnets are arranged in said internal portion of said rotor core; said auxiliary magnetic pole piece portions are formed between adjacent permanent magnets in a peripheral direction, said magnetic air gaps are formed in said internal portion of said rotor core, and said magnetic air gaps are formed at an end portion of a peripheral direction of said permanent magnets, thereby a change of a magnetic flux density distribution between said magnetic pole piece portions and said auxiliary magnetic pole piece portions is formed smoothly and a cogging torque is restrained; and a width in a peripheral direction of a side of said magnetic air gaps facing said stator is formed larger than a width in a peripheral direction of a radially inward portion of said magnetic air gaps.