| 摘要 |
PURPOSE:To facilitate the formation of magnetic poles of a magnet, by alternately arranging a first magnetic pole pair consisting of an N pole and an S pole having a wide magnetic pole angle and a second magnetic pole pair consisting of an N pole and an S pole having a narrow magnetic pole angle. CONSTITUTION:An annular magnet 5 fixed on the inner surface of a rotor 1 and magnetized is provided with N poles and S poles which are alternately located, and has alternately a first magnetic pole pair consisting of an N pole and an S pole having a magnetic pole angle of 120 degrees and a second magnetic pole pair consisting of an N pole and an S pole having a magnetic pole angle of 60 degrees. Armature coils 9, 10, 11 and 12 are disposed on the outer periphery of an armature iron core 7 so that the effective pitch thereof is equal to 60 degrees, the angle between the magnetic poles of the second magnetic pole pair of the magnet 5 and moreover said coils have a phase difference of 90 degrees, 1/4 of the magnetic pole period, 360 degrees, of the magnet 5. Thereby, the formation of magnetic poles of the magnet is facilitated. |
