| 摘要 |
<p>PURPOSE:To improve the stability of a DC motor due to temperature by transmitting a firing signal from a firing angle setting value side to a triac control signal via photocoupling means. CONSTITUTION:A counter 6 is reset by a zero-cross detection signal E1 of a voltage ESO outputted from a zero-cross detector 5 and starts counting of the output pulses E3 of an oscillator 8. When the counted value of the counter 6 reaches the set value set by a setter 7, a signal E2 is applied to photothyristor couplers PS1, PS2. In this manner, a triac TR is turned ON, and turned OFF at the zero cross point of the current ISO flowing through the triac TR. Thus, a rotating speed controller which can digitally set the rotating speed with stable temperature can be obtained.</p> |
