| 摘要 |
PURPOSE:To widen the range of temperature measurement and at the same time make it possible to provide a thermocouple with longer life and use an inexpensive thermocouple by following up the rate of temperature change in the process of temperature increase to calculate the saturation temperature. CONSTITUTION:A block 2 is connected by a thread to a thermocouple 1 and both are inserted into an object 12 to be measured. The output of the thermocouple 1 sent through a smoothing filter 13 to differentiation section 8. There the indicated temperature theta(t) is differentiated, and an inferred value theta0(t) is sought according to the formula in the figure at an inferred temperature calculation section 9. When the absolute value of the inclination that is given by linear regression of theta0(t) is smaller than a beforehand specified value that is near zero, the temperature measurement is finished, and when the abolute value is larger than the specified value, the correction values for temperature variation values T1 and T2 that satisfy the relation T2=0.4T1 are sent to an arithmetic section 9. As a result it is possible to reduce theta(T0)/theta0 to 0.4-0.5 after the time T0 to start inference, making it possible to use the thermocouple in the range as large as two times the ordinary range, and longer life of the thermocouple and use of an inexpensive thermocouple can be realized. |
