| 摘要 |
PURPOSE:To improve the productivity by providing an auxiliary coil always excited in the prescribed polarity at part of a stator core, thereby improving the efficiency without necessity of adopting a complicated structure to gradually lengthen a gap. CONSTITUTION:A stator core ST is formed of 4 main poles 11a, 11d, and a coil L1 wound on the poles 11a, 11c, and a coil L2 wound on the poles 11b, 11d are wound in two phases. An auxiliary coil L3 is wound on the poles 11a, 11b, and a position detector H of a rotor such as a Hall element is disposed between the pole teeth of the poles 11a, 11b. Further, a ring-shaped rotor RT made of a permanent magnet is arranged around the stator core ST. The coils L1, L2 are sequentially excited, and the coil L3 are always excited, thereby rotating the rotor RT. |
