| 摘要 |
PURPOSE:To reduce the torque ripple of a step motor at the constant speed operation time as compared withthe torque ripple at the starting time by reducing the rotary step angle at the constant speed operation time as compared with the rotary step angle at the starting time. CONSTITUTION:The exciting times of the respective phases at the starting time are read out from a time table 15 in a memory which stores the exciting time determined at every step at the starting time. A phase changeover controller 5 and a current value controller 4 are controlled on the basis of the exciting time to control drivers DA-DD and current limiting drivers 10, 11, thereby controlling the starting of a step motor 1. When becoming the constant speed operation state, the CPU 2 reads out the exciting phase data and the exciting current data thereto from an ROM 3 to perform the ultrafine step control, and delivers them to the controller 5 and the controller 4. In this manner, the variation in the torque of the step motor at the constant speed running time can be suppressed to small value. |
