| 摘要 |
PURPOSE: To reduce hysteresis in characteristics, which are not critical, by performing the switching of the exciting strength of a step-motor driving means when the step motor is stopped at a different pattern for every step motor coil, and performing settling. CONSTITUTION: When signals DIR and STEP are inputted into an exciting control circuit 3, transistors 10 and 11 are both turned ON, exciting-phase signal outputsϕA-ϕD of the exciting control circuit 3 are sequentially switched and a step motor is rotated. When the step motor is stopped, the STEP signal is not inputted and fixed to the total of two phase signals of any of the exciting- phase signal outputsϕA andϕC and any of the exciting-phase signal outputsϕB andϕD. Then, the strong and weak signal outputs PA and PB are alternately switched and step motor coils 1 and 2 perform the small oscillation. Finally both strong and weak signal outputs PA and PB are strongly excited and settled. Thus, the hysteresis of the step motor can e reduced, and the head moving device having the excellent position accuracy can be realized. |
