Patent ID: 6822360
Filing Date: 2004-11-23
Classification: H02K

Abstract:
An electromotive vehicle drive using 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 portions for generating a reluctant torque, magnet pole piece portions for transmitting a magnetic flux of said permanent magnet to a side of said stator, and magnetic air gaps for restraining a cogging torque are formed in said rotor core; wherein: to form said magnetic pole piece portions, said permanent magnet insertion holes are formed by punching out said rotor core in an axial direction, thereby said permanent magnet insertion holes are arranged in a ring-shape in an internal portion of said rotor core; said permanent magnets are inserted into said permanent magnet insertion holes alternately with a reversed polarity, thereby said permanent magnets are arranged in said internal portion of said rotor core; said auxiliary magnetic pole portions are formed between adjacent permanent magnets in a peripheral direction; and said magnetic air gaps are respectively formed in said internal portion of said rotor core between peripheral direction end portions of one of said permanent magnets and adjacent ones of said auxiliary magnetic pole portions, thereby a change of a magnetic flux density distribution of said permanent magnets between said permanent magnets and said auxiliary magnetic pole portions is formed smoothly.