| 摘要 |
<p>PURPOSE: To supply the control signals of a size required for overcoming the sealing preload of a valve to a control valve by providing a target flow rate comparator circuit for outputting signals based on the compared result of a target flow rate and a target flow rate threshold signal. CONSTITUTION: A control circuit 12 controls a flow rate control valve 16 by using information received from a sensor 14. That is, a subtraction circuit 20 detects a difference between setting point signals SP and real flow rate signals FLOW received from the sensor 14 and outputs the difference to an integration circuit 22. A threshold detection circuit 26 provides pedestal signals by using thresholds VTH1 and VTH2 and considering operations performed by a system 10 heretofore. Then, the pedestal signals are added to the output of the integration circuit 22 in an addition circuit 24. Thus, the control circuit 12 outputs the signals for overcoming the preload of the valve 16 and the flow of fluid in the system 10 is started.</p> |
