| 摘要 |
<p>PURPOSE:To prevent a reckless runaway of a motor by changing over to a detection signal of the motor side when an abnormality comes to the detection signal of the motor side. CONSTITUTION:When a voltage detection signal is higher than reference voltage, the output of an operational amplifier 15 is L. In other words, a priority circuit 12 controls a switch circuit 13 to be off, and the voltage detection signal is outputted to the next step gain automatic regulating circuit 5 as a rotation detection signal. While, when the voltage detection signal is lower than reference voltage, the output of the operational amplifier 15 is H, and a diode 17 is biased reversely. In other words, the switch circuit 13 is controlled to be on, and a speed detection signal is outputted to the next stage gain automatic regulating circuit 5 through a diode 18 as the rotation detection signal. According to the constitution, the safety is secured.</p> |
