| 摘要 |
PURPOSE:To prevent abrasion of a shaft through a smooth drive control even at a low speed by changing the ON-time of each sect sine-functionwise in response to the progress of sects and also by applying a constant voltage to an excitation phase in synchronization of the ON-time of each sect. CONSTITUTION:A base current is applied to a specific transistor (such as TRA) from an output port 15 in a control equipment 11, which energizes a collector electrode and emitter electrode of this transistor. Because of this, a voltage of a common power supply 16 applied to an excitation coil (phiA) corresponding to this transistor, a magnetic field is generated and a step motor M is driven. When the base current from the output port 15 is turned off, the applied voltage to the excitation coil (phiA) is turned off and the magnetic field of its phase disappears. Operation unit 14 ordinarily excites two of four excitation phases of the step motor M by means of two-phase excitation program 19 stored in ROM 18 and then turns and drives the step motor M by sequentially replacing the objects to be excited. |
