Patent ID: 6849981

Claim:
A permanent magnet-type electric motor, comprising: a stator; and a rotor having a magnetic field and disposed in the stator such that a reverse magnetic field is generated by said stator, said rotor including a plurality of permanent magnets forming a magnetic poles are inserted in magnet insertions of a yoke such that the magnets form in line in a circumferential direction thereof, each of said magnets including at least first and second magnets that are divided in the circumferential direction of said yoke, said first magnets being positioned in locations of high demagnetization resulting from the reverse magnetic field of said stator relative to the, magnetic field of said rotor while said second magnets being positioned in locations of low demagnetization resulting from the reverse magnetic field of said stator relative to the magnetic field of said rotor, said first magnets having a greater force of retaining magnetism than said second magnets, and said second magnets having a greater magnetic flux density than said first magnets.