| 摘要 |
PURPOSE:To move at a high speed by providing a plurality of coils as a driving coil, and switching the plurality of coils in series or parallel connection according to the moving state of the driving coil. CONSTITUTION:A driving coil 2 has a plurality of coils 3, 4 and is changed-over by change-over means 5, 6 to connect the coils 3, 4 in series or parallel connection according to the moving state of the coil 2. Accordingly, when more thrust is required such as when the coil 2 is accelerated from its stopping state, when it is decelerated from a moving state at a high speed, or when it is operated to position, the coils 3, 4 are connected in series to increase its thrust per unit current, and the coils 3, 4 are connected in parallel in a state that the speed is accelerated to a certain degree or higher. |
