| 摘要 |
PURPOSE:To improve the reliability of an apparatus, by forcibly controlling the frequency of a frequency signal below a self-starting frequency, when a step-out detection circuit judges said apparatus to have stepped out, in such manner that said apparatus restarts automatically and one can use it without anxiety even under the conditions where such step-out occurs. CONSTITUTION:A difference voltage V outputted from an amplifier 10 is inputted to a slow-up circuit 13 and also to a step-out detection circuit 14. Said step-out detection circuit 14 judges an apparatus to have stepped out when a difference voltage V exceeds a limiting voltage Vm and sends a reset signal to the reset terminal R of said slow-up circuit 13. Thus, the frequency of a frequency signal F to be applied to a stepping motor 5 is forcibly controlled below a self-starting frequency for a given duration. Therefore, the step motor 5 starts its rotation by itself in the meantime. |
