| 摘要 |
PURPOSE:To simplify a structure and control the rotational direction without spoiling the characteristics of a synchronous motor, by arranging a boss fixing a fan or the like at a specified position on the rotor shaft of a permanent magnet rotor, to be freely rotated around the rotor shaft. CONSTITUTION:A driving gear is organized by arranging a boss 19 fixing a fan 20 or the like,load at a specified position on the rotor shaft 13 of a permanent magnet rotor 12, to be freely rotated around the rotor shaft 13. On driving, when AC voltage is applied to a driving coil 15, then alternating field is generated on the magnetic pole sections 16, 16 of a stator core 11, alternately with poles N-S and poles S-N. The permanent magnet rotor 12 receives repulsive and attractive actions from the alternating field, and vibrates rotationally in the right and left directions. The rotationally vibrating force is transmitted to the boss 19 having the fan 20 for load, via a conic torsional spring 21 wound up on the rotor shaft 13, but the boss 19 is directed to be put in a static state by the inertia force of the fan 20, and the conic torsional spring 21 is displaced. In this manner, the rotor shaft 13 is elastically connected to the boss 19 with the spring 21, and so the rotational direction can be controlled without spoiling the characteristics of a synchronous motor. |
