| 摘要 |
PURPOSE:To facilitate the regulation of the set value of a resonance rotating speed by providing a comparator which outputs a signal when an input value exceeds the prescribed value, and an amplifier for limiting the input signal stepwisely by the output signal of the comparator. CONSTITUTION:A calculator 13 compares a set signal 10 wit a feedback signal 11 and outputs a speed set signal Vi. The signal Vi is limited to the value set by a potentiometer 17 by a limiter. Further, when the signal Vi is increased and increased larger than the added value of the value of the potentiometer 17 and the value of a potentiometer 19, a comparator 20 outputs a signal, and the limiter value increase. Thus, the regulating operation is simplified. |
