| 摘要 |
PURPOSE:To prevent the lowering of torque on high speed, and to reduce the noises of driving on low speed by selecting the application or non-application of high voltage on the changeover of phase in response to speed. CONSTITUTION:On high speed, transistors 3 are turned ON by a reference pulse signal, switches 5 and 6 are each switched and driven by a driving signal A, an inversion signal A, a driving signal B and an inversion signal B determined by a reference pulse signal, and exciting signals in which the driving signals are overlapped to several phase input signal are transmitted over motor coils 2, thus acquiring high-speed high torque characteristics. The switches 5, 6 are brought to an OFF state at all times on low speed. Accordingly, the exciting signals for the coils 2 are changed into rectangular pulse signals on which the driving signals are not superposed, thus reducing a voltage value on pulse rise, then minimizing the noises of driving. |
