| 摘要 |
PURPOSE:To reduce useless magnetizing intervals by alternately generating plus or minus pulse current by a pulse current generating circuit for supplying power to a yoke coil. CONSTITUTION:A coil 13 is wound each approx. 20 turns in the direction of adding ampere-turns on both sides of a yoke 12 provided with, e.g., a gap 12a of 0.1mm at the front end of the yoke and the back end of the yoke is closed. At the time of magnetizing, magnetic flux is generated in the gap 12a by supplying a pulse current to the coil 13 from a pulse current generating circuit 14 in synchronous with the rotating drive of a motor control circuit 18. 480 pulse currents of pulse width 100mus is plus-or-minus-alternately supplied per one rotation of magnetic plastics 11. That is, the alternately reverse direction magnetic flux performs magnetization at the interval of approx. 0.3mm and, as a result, a pair of the same polarity is placed in parallel for each magnetic pole and the non-magnetization between magnetizing intervals or a weak useless magnetizing region is reduced. |
