| 摘要 |
PURPOSE:To obtain heating characteristics that have good reproductivity by providing a circuit means to calibrate the output of a current sensor for temperature control in the stages of drying and ashing by means of output of a temperature sensor for temperature control in the stage of atmizing. CONSTITUTION:The output from a temperature sensor for a heating furnace is compared with a reference voltage Vr that corresponds to the maximum temperature of the heating furnace by means of a comparator 30 via a preamplifier 18. When the output exceeds the reference voltage Vr, a display device 31 is lighted to display, and when it is equal to Vr, it flickers. The output Vi of an electric current sensor for furnace heating current is inputted to an error amplifier 20 via a preamplifier 15 and a change-over switch 19, and compared with a reference voltage Er (Er=Vr) from a temperature programmer 21 and the heating current is controlled by the difference of the outputs. The output Vt of the preamplifier 18 is compared with Er in the same way by changing over the switch 19 to the B side. If Vi is not equal to Vt, the gain regulator 32 is adjusted to control the heating current until the display device 32 flickers. Accordingly heating characteristics with good reproductivity are obtained. |
