| 摘要 |
PURPOSE:To simplify both circuit constitution and structure of an operation panel surface, by setting the set value in the form of an analog signal of the same type as the detecting signal of a controlled system and then supplying the analog signal after converting it into a digital signal. CONSTITUTION:The set value is set in the form of an analog signal of the same type as the detecting signal of a controlled system. A means is provided to convert the analog signal into a digital signal and supplies the digital signal. For instace, a temperature setting button 9 is pushed to switch a changeover switch 8 to the side of a contact (b) by means of a central processor 4. Then the voltage of the slider of a potentiometer 7 is supplied to an A/D converter 3 to be stored in the processor 4 in the form of a digital signal as well as to be displayed to a display device 10 as a set value. Then the button 9 is pushed again to set the switch 8 at a contact (a) by the controller 4, and the signal sent from a temperature sensor 1 is detected by a temperature detecting circuit 2 and supplied to the converter 3. A temperature control circuit 11 is driven so as to obtain the coincidence between the output signal of the converter 3 and the set value, and the current of a heater 12 is controlled. |
