Patent ID: 6876117

Claim:
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 reluctant torque, magnetic pole piece portions for transmitting a magnet flux of said permanent magnet to a side of said stator, bridge portions for connecting between said magnetic pole piece portions and said auxiliary magnetic pole piece portions, and magnetic air gaps are formed in said rotor core; wherein to form said magnetic pole piece portions in said side of said stator, said permanent magnet insertion portions are formed in said rotor core, and said permanent magnet insertion portions 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 bridge portions are arranged between said magnetic pole piece portions and said auxiliary magnetic pole piece portions, and said bridge portions are formed in accordance with a formation of said magnetic air gaps; said magnetic air gaps are formed in said internal portion of said rotor core, and said magnetic air gaps are formed between said magnetic pole piece portions and said auxiliary magnetic pole piece portions, thereby a change of a magnetic flux density distribution of said permanent magnets between said permanent magnets and said auxiliary magnetic pole piece portions is formed smoothly; and further said magnetic air gaps extend over from both end portions of said magnetic pole piece portions to said side of said stator, and lengths in radial directions of said bridge portions are formed short, thereby a leakage of a magnetic flux of said permanent magnets from said magnetic pole piece portions to said auxiliary magnetic pole piece portions through said bridge portions is restrained.