JPS60169729A - Calibrating method of temperature sensitive element and temperature measuring method using temperature sensitive element - Google Patents

Abstract

PURPOSE:To obtain highly accurate calibration data for every piece of thermistors to be calibrated by easy operation, by constituting the device based on the detected value of the thermistor to be calibrated at a calibrating temperature point. CONSTITUTION:Temperature sensitive elements, which are bodies to be calibrated 23a-23q, comprise a platinum temperature measuring resistor, a thermistor element, or a thermocouple, and the like, which are not calibrated yet. The measured temperature data of the resistor and the thermistor elements are expressed in resistance values. The data of the thermocouple is expressed in output voltage value. When a hot junction is provided in a temperature environment part 21 for the thermocouple, the temperature of a cold junction should be kept at the other comstant temperature. A switch part 24 has a multiplexer function, by which one of a reference temperature measuring body 22 and the bodies to be measured 23a-23g are selected and connected to a measuring part 25, namely multiple inputs and outputs are selected, in accordance with the control of a control part 10. The measuring part 25 measures the resistance value of the reference temperature measuring body 22 to be measured in accordance with the measuring clock from a clock generating part 13. The measured resistance value is converted into digital data by a built-in A/D converter function, and the data is sent to an operating part 12.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Technical Field of the Invention The present invention relates to temperature-measuring confectionery, particularly to improvements in a calibration method for a temperature-sensing element and a temperature-measuring method using a temperature-sensing element.

(b) Background of the technology Conventional methods for measuring temperature include primitive mercury and alcohol thermometers that use the thermal expansion of objects, pressure thermometers that measure the rise in pressure within a volume as a pressure gauge, gas thermometers, and luminance. From optical pyrometers that measure temperature by comparing it with a standard light source, to platinum resistance thermometers that utilize temperature changes in electrical conductivity, thermistor thermometers, and thermocouples, etc. 〇Temperature measurement means for industrial applications such as normal temperature control etc. The latter electrical method is used, but platinum resistance thermometers and thermocouples can achieve highly accurate temperature measurement, but are expensive, have low sensitivity, and require a certain cold point for use. In contrast, thermistor thermometers are widely used due to their high sensitivity and low cost.

(c) Thermistor has been widely used as a typical temperature-sensitive element, but thermistor in a broad sense utilizes the characteristic that the electrical resistance of a semiconductor changes greatly depending on the temperature. Body! They are classified into ordinary thermistors with a positive temperature coefficient, ■positive characteristic thermistors with a positive temperature coefficient, and ■critesisters whose resistance changes suddenly over a narrow temperature range. Below, we will explain a typical thermistor with 0 term as a typical example.
n.

Co * Nl * Fe * Cu e V and W
Oxides such as complex oxides based on transition gold JI14 oxides, resistivity and temperature Ba + Na, etc. are added.

The relationship between the temperature and resistance of a thermistor is the same as that of an intrinsic semiconductor in the practical temperature range: ρ=I)oeχp(ΔE/2kT)
is given by Here, ΔE is activation energy. ◎In a normal thermistor, B=ΔE/2k is called the thermistor constant, and the temperature dependence of resistance is expressed by the resistance/temperature calculation formula % formula %. Here, Rref is given a value of B=5020 to 6140 around room temperature. Therefore, while the temperature detection function of a thermosensor using a thermistor has extremely high temperature measurement sensitivity compared to other platinum resistance meters and thermocouples, it is difficult to detect crystal distortion due to the aforementioned complicated material composition and the influence of firing heat treatment, etc. Due to contact changes, the temperature characteristics of the thermistor's resistance become an exponential curve of equation 0.B
The disadvantage is that there are large variations in characteristics including
In an extreme example, if B shows a different value for each temperature, sufficient correction cannot be obtained, so creating a thermistor calibration method that achieves temperature measurement accuracy better than ±1°C, for example, is a troublesome problem. (d) Purpose of the Invention The purpose of the present invention is to eliminate the above-mentioned drawbacks and problems by providing a working temperature range that can be obtained for a plurality of q thermistors by combining a precise reference temperature environment for calibration and a standard temperature measuring element. Based on the detected value of the thermistor to be calibrated at a plurality of calibration temperature points over a plurality of calibration temperature points (\ is the resistance value), a means for requesting corresponding to each thermistor to be calibrated by the above-mentioned formula 0, and further B (
Temperature error correction formula to obtain the difference Δt between the calculated temperature value obtained by substituting in 1 and the standard temperature value obtained by the standard thermometer Δt=a+
bx+cx” ・・・・・・nxIn ・・・・・・
. . . constitutes a temperature calibration device t that executes the means for determining
The present invention aims to provide a calibration method that is easy to operate and allows high n-degree calibration data to be obtained for each cylinder piece of a thermistor to be calibrated.

(e) Structure of the Invention This purpose is to compare a plurality of temperature sensing elements with a standard temperature measuring element in a reference temperature environment and obtain calibration data for temperature indications associated with the output or resistance of the temperature sensing elements. In the temperature calibration system for the temperature sensing element, the temperature calibration device for the temperature sensitive confectionery includes a reference temperature environment means using a constant temperature chamber whose temperature can be set, a standard MTL body as a calibration standard, the standard temperature measuring body and the subject to be calibrated. a means for measuring the edge or resistance of J number of temperature-sensitive sweets, a switching means for selecting a standard heating body or a calibration target to be measured in the environmental means and connecting it to the measuring means; storage means for accumulating measurement data and each calculation data associated with calibration, a characteristic constant of the object to be measured according to the measurement data, an permanent correction value obtained by substituting the constant at-temperature calculation 2, and a reference value by the standard side temperature body. comprising a calculation means for obtaining correction data for the measurement means, a clock generation means for sending out a measurement clock for the measurement means, and a means for displaying/outputting various data in the measurement means, storage means, etc.,
The control unit of the constant pressure device uses the switching means to select and measure the standard heating body installed in the environmental means and the temperature-sensitive candy as the object to be calibrated for each of the two calibration temperatures set by the environmental means. and the measuring means measures the output or resistance value of the standard temperature measuring object/calibration object according to the clock signal of the clock generating means.

The measured data is input to the calculation means to calculate the characteristic constants and correction data of the object to be measured, and the measured data tf
c is necessary by accumulating the calculated data in the storage means.
) This can be achieved by providing a temperature-sensing element calibration method characterized by outputting measured and/or calculated data using a display/output means.

G) Embodiment of the Invention An embodiment of the invention will be described below with reference to the drawings. FIG. 1 is a block diagram of a temperature calibration device using a temperature-sensing element calibration method according to an embodiment of the present invention, FIG. FIG. 3 is a block diagram of a chant measuring device using a temperature measurement method using a temperature sensing element in another embodiment, and FIG. 4 is a flowchart showing the processing procedure of the temperature measurement method using a temperature sensing element in another embodiment.

In the figure, 10 is a control section, 11 is a storage section, 12 is a calculation section, 13 is a clock generation section, 14 is a display/output section, and 2
1 is a temperature environment section, 22 is a standard thermometer, 23a-q are temperature sensing elements to be calibrated, 24 is a switching section, and 25 is a measurement section.0 Control section 10 is a central processing unit (CPU) or a microcontroller. It is composed of a processor (MPU) and has a storage unit 1.
Although not shown, the O storage section 11 controls the other components of the temperature calibration device in accordance with the control program and control data stored in a separately built-in storage means to execute the calibration mode of the objects to be calibrated 23a-q. This is a memory function that stores measurement data, calculation data, etc. generated in conjunction with calibration operations, and is usually stored in semiconductor-based Daimic random access memory (D-RAM), static random access memory (S-RAlvl), or if necessary. Fixed memo IJ (RO
M) Furthermore, the external storage means for the data buffer file diagram shall be constituted by a floppy disk device, a magnetic disk device, etc. The Q calculation section 12 receives measurement data and stores the measurement data from the corresponding control section IO. In addition to storing the measurement data in the storage unit 11 as a measurement data table in correspondence with control input data, measurement data corresponding to a specified temperature value Tref in the temperature environment unit 21 (described later) is stored in the measurement data/temperature calculation formula described above. By substituting into the equation 0, the temperature conversion constant of the valley mixer is calculated.
Thermistor constant Ba-q/Trefe in 3a-q
Substituting the constants Ba~q, which have the function of calculating
When each measurement data of the object to be calibrated at +-P is inserted, the calculated temperature of the primary correction corresponding to the measurement data is calculated 1 shift t I-P
is obtained, but except for the Tref point, this IiL is determined by the standard 1$ thermometer 22 in the previous measurement data life table ~T
Unlike the reference temperature values of 1 to Tp, the temperature sensing element 23m has an error Δ
t1' ” 'f' r tea , Δtea = Tt
-tta """ Δt p,='l'p tpt, so constant data of ΔL1a to Δtpq is required. Temperature error correction formula One-difference correction of temperature sensing element 23a, which conflicts with the error correction formula of equation (2) above. Formula A ta=Ikm+klix+caX” ---n6x
” −・= 2x formula tX output / Other sense @ element 23
Similarly, for b to q, the bladder output correction formula of Δtb, . Further, the provisional calculation unit 12 that has obtained the correction data in the storage unit 11 has a calculation function that accesses the corresponding correction data, corrects the measurement data of the heat-sensitive element, and outputs the correction data. For example, the clock generator 13 counts down the system clock of the control unit 1O to keep the measurement conditions constant by generating the voltage/IIE current applied to the standard temperature measuring element 22 or the calibrated object 23m to be measured. It has the function of sending out a measurement clock to control the time at a certain time. The display/output section is a means for displaying/outputting various data in temperature calibration/measurement operations, such as measurement data, correction data, or corrected correction data, and is composed of, for example, a CRT display, printer, or X-Y plotter, and a keyboard if necessary. The 0-degree environment unit 21, which has input operation means such as
Equipped with heating, cooling, and reflux stirring functions for the fluid in the tank to maintain a constant temperature value according to the specified set value.
The triple point of the temperature environment [21 is water Gtno if necessary] or the boiling point of H2O may be used. Standard temperature measurement/body 2
2 is used as a reference device in temperature calibration using, for example, a platinum resistance thermometer; it can also be used for temperature detection of the temperature environment section 21. The temperature sensing element serving as the object to be calibrated 23&~q is an uncalibrated platinum side temperature resistor.

Thermistor element or thermocouple, etc., and the temperature measurement data of the former two depends on the resistance value, and the latter depends on the output voltage value.In addition, in the latter case, when the hot spot is installed in the temperature environment section 21, the cold spot is at another constant temperature. The 0 switching unit 24, which must be maintained at Multiplexer of Choice (MPX)
It is a function. The measuring unit 25 has a detection function that measures the resistance value of the platinum-side temperature resistance element in the standard temperature measuring body 23 to be measured or the thermistor in the calibration target 23a-q- in accordance with the measurement clock of the clock generating unit 13. The resistance measurement value is converted into digital data by the built-in A/D conversion function and sent to the calculation unit 12.@Since this embodiment is configured as described above, the control unit 10 is the procedure according to the flowchart in Figure 2.
=a l Control the calibration mode according to 9 ◎Procedure & l
Then, the temperature environment section 21 is set to the initial value T=1, for example, the lowest temperature value in the operating temperature range, and in step a4, the switching section 24 is set to the initial value of the object to be calibrated 23&~q, for example, the initial value=1, that is, the object to be calibrated 23& is connected to the measuring section 25. In step a5, measurement section 2
5 is the object 2 to be calibrated at the set temperature T of the temperature environment section 21.
In the measurement data 3&, the resistance value rta is converted into digital data and sent to the calculation s12, and the calculation section 12 stores it in the storage section 11 in correspondence with the control data. Following steps a4+a5, perform step 1 for each individual piece of temperature sensing element 23 & -q at the set temperature T of temperature environment section 21.
When q measurements are completed in step 6, the set temperature of the temperature environment section 21 is set to another temperature T, and step al-a6 is repeated.
Hand J [all set temperatures T with a7! ~About TP Temperature sensing element 2
3a=(l measurement data is obtained. At this time, the storage unit 11
A measurement data table as shown in Table 1 is stored in .

Table 1 Measurement data table example Next, the calculation unit [2] Checks the temperature point specified by the control unit 10 by the hand I@&8, for example, the intermediate temperature point TP/2, and the temperature point T
As ref, the characteristic constant is calculated by the resistance/temperature calculation formula.
Then, the thermistor constants B are calculated as Ba-q(i) corresponding to the temperature sensing elements 23a-q, respectively.

This Tref may be the lowest temperature point T1, the highest temperature point Tp, or any other set temperature.

Table 2 Thermistor constant Ba-q table Next step a
9, the calculation unit 12 calculates B a to (l rla-pm, rib in Table 1) of Table 2 for each temperature sensing element 23a to 23q.
-pb ”...rIq-9Qt- By substituting into equation (1), the primary calculated temperature value when constant Ba-ql is constant for each temperature sensing element 23a-q can be obtained as shown in Table 3. 〇Table 3 Calculated temperature value table example This calculated temperature value has a slight error in the normal setting temperature values T and ~p, except that Fi1 difference is zero at Tref, and ΔLi
a=Ts~tta, Δtme=T*~tea・−
...Δtpq = correction type correction sound temperature sensing element 23&~q
0, that is, Δta = am + t) a X+
1! aX' --n,! ” ・-・'2 a formula below 2b
~ 2q formula is obtained and stored in the storage unit 11. If necessary, the control unit 10 outputs the measurement data, each table, or error correction formula 2a"q from the storage unit 11 and displays/outputs the output unit 14t. /Draw and output・The data transmission path (bus) between each component of the temperature calibration device shown in Figure 1 is usually GPIB in the measurement system.However, it goes without saying that it can be similarly realized using other interfaces. As described above, the temperature sensing elements 23a-q can easily perform highly accurate calibration.Next, another embodiment will be described with reference to the drawings.FIG. 3 shows the present invention. A block diagram showing a temperature measuring device using a temperature sensing element in another embodiment of the present invention and FIG.
It is a flowchart showing. In the figure, 10 is a control unit;
1 is a storage section, 12 is a calculation section, and 13 is a clock generation section.

14 is a display/output section, 21 is a temperature environment section, 22 is a standard thermometer, 23a-q is a temperature sensing element of the object to be calibrated, 23a-q
24 is a switching section and 25 is a measuring section. The above-mentioned 3M is a component of the temperature measuring device shown in the figure.
Components having the same reference numerals as in FIG. 1 have functions and characteristics common to those in the previous embodiment. The function of the control unit 10 is the same as that of the conventional control unit 10.
The difference is that J is added.

Therefore, the processing procedure of the calibration mode by the control unit 10 in the temperature measurement system of the other embodiment shown here is common to all the processing procedures a1 to alO shown in FIG. 2 in the temperature calibration system described above.

In the measurement mode, according to procedure bt, the temperature sensing element 23 &~(
L' (l: Practical temperature measuring element 23' taken out from the temperature environment section 21
Attach to the temperature measuring object as a-q ・This work is a manual operation @ Attach to the calibrated object and the practical temperature measuring device The setting of measurement time interval tit--zero measurement points q to be set is common to the prior art. Step b3
11, for example, by a built-in timer, and determines whether the practical temperature measuring elements 23a-q have fallen.For example, the initial value is q.
=1, the switching section 24t- selects the practical temperature measuring element 23'a and connects it to the measuring section 25, and the clock generating section L3
t-, the measurement clock is sent out, and the measurement data is sent out to the arithmetic unit 12 in step b4.

In step 1 [b5, the calculation unit 12 accesses the storage unit 11 and accesses correction data such as B& of the constant table and error correction corresponding to the practical temperature measuring object 23a, that is, the object to be calibrated 23& obtained in the calibration mode, and performs measurement. Corrected measurement data (temperature fi) IC conversion/calculation and display/output [14
Make more output. According to step 6, other practical thermometer 23b-
Corrected measurement data can be obtained by performing the same procedure for q. If ti has further elapsed, the control unit [O is step bt-ba
'i Repeat measurement mode t - Disaster If you set it to 0 or more, you can calibrate the temperature sensing element in temperature measurement using the temperature sensing element.
Changing the measurement mode requires manual operation when changing the mounting location, but otherwise the control unit 10 executes the calibration/measurement mode according to preset procedures and displays/outputs highly accurate temperature measurement results with easy operation. I can do it. In the above, the measurement data in the calibration/measurement mode was corrected using the error correction formula, but if p in T and ~p is sufficiently large, corrected measurement data can also be obtained by interpolation. do not have.

As described in detail, according to the present invention, it is possible to easily calibrate and measure with high accuracy even when using a temperature sensing element, particularly a thermistor, which conventionally has characteristics of high sensitivity and low cost but low measurement accuracy. This method is useful because it provides a calibration method for the thermosensor and a temperature measurement formula using the thermosensor that yield results. It goes without saying that this method can be similarly applied to other temperature measurement sensors.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a calibration device using a temperature sensing element measurement method according to an embodiment of the present invention, FIG. 2 is a flowchart showing the calibration process procedure, and FIG. FIG. 4 is a block diagram showing a temperature measuring device using an element-based temperature measuring method, and a time chart showing a processing procedure in the measurement mode. In the figure to
, t. is a control section % 11 is a storage section, t2 is a calculation section, 13 is a clock generation section, 14 is a display/output section, 21 is a temperature environment section,
22 is the standard temperature measuring object, 23a-q are the temperature sensing elements% of the object to be calibrated.
23a-q are temperature sensing elements of the practical thermometer, 24 is a switching section, and 25 is a measuring section.

Claims (1)

[Claims] (1) Calibration data for the temperature indication value associated with the output or resistance of the thermosensor is obtained by comparing the thermosensor with a standard thermometer in a reference temperature environment. In the temperature calibration system for the temperature-sensing element, the temperature-calibration device for the temperature-sensing element includes a reference temperature environment means using a constant temperature chamber whose temperature can be set, and a standard temperature measuring body as a calibration reference.The standard temperature measuring body and the subject to be calibrated. a means for measuring the output or resistance of a plurality of temperature sensing elements serving as a body, a switching means for selecting a standard temperature measuring object or a calibrated object to be measured in the environmental means and connecting it to the measuring means, and measurement by the above measuring means. Storage means for accumulating data and each calculation data associated with calibration, correction of the characteristic constant of the object to be measured according to the measurement data, the primary correction value obtained by substituting the constant t into the temperature calculation formula, and the reference value by the standard temperature measuring object. calculation means for obtaining data;
Displays/displays various data in the clock generation means that sends the measurement clock of the measurement means, the measurement means, the storage means, etc.
The control section of the calibration device is equipped with a means for outputting the standard temperature measuring element installed in the environmental means and a temperature sensing element of the object to be calibrated for each calibration temperature P(la) set by the environmental means. Select and connect to the assembling means, have the measuring means measure the output or resistance value of the standard temperature measuring element/object to be calibrated according to the clock signal of the clock generating means, and input the measured data to the calculating means. It is necessary to calculate the characteristic constants and correction data of the object to be measured and to store the measurement data and/or correction data in a storage means. (2) Calibration method for temperature-sensing elements characterized by: (2) Calibration method for temperature-sensing elements characterized by measuring the output of the temperature-sensing elements or In a temperature measurement system equipped with a temperature calibration means for a temperature sensing element that obtains calibration data for a temperature resistance value associated with a resistance, the temperature measurement device for the temperature sensing element is equipped with a reference temperature environment means in a constant temperature chamber whose temperature can be set, and a temperature measurement system for calibration. A standard temperature measuring device as a reference, a means for measuring the output or resistance of a plurality of temperature sensing elements serving as the standard temperature measuring device and the calibrated/practical temperature measuring device, a standard temperature measuring device to be measured in the environmental means, or A switching means for selecting and connecting the object to be calibrated to the measuring means, a storage means for storing measurement data by the measuring means and various calculated data associated with calibration, and a characteristic constant of the object to be measured and the constant total temperature according to the measurement data. Measurement by calculating means and measuring means to obtain corrected measurement data by accessing the correction data of the primary correction value obtained by substituting it into the calculation formula and the reference value by the standard thermometer, and the correction data in the storage unit corresponding to the measurement data. It is equipped with means for displaying/outputting various data in clock generation means, measurement means, storage means, etc., and in the calibration mode, the control section of the temperature measuring device is configured to set two calibration temperatures using the environment means. The standard temperature measuring element installed in the means and the temperature sensing element of the calibrated/practical temperature measuring element are selected by the switching means and connected to the measuring means, and the measuring means measures the standard temperature according to the clock signal of the clock generating means. Measures the output or resistance value of the object to be measured and the temperature measuring object to be calibrated/practical.The measured data is input to the calculation means to calculate the characteristic constants and correction data of the object to be measured, and the measured data and/or correction data are stored. At the same time, it is transferred to the object to be measured in the measurement mode and the next
The temperature sensing element of the practical thermometer is selected by the switching means and connected to the measuring means, and the measuring means measures the output or resistance value of the temperature body to be calibrated/practical side according to the clock signal of the clock generating means. Inputting the measured data to the calculation means, while causing the calculation means to access the correction data stored in the storage means corresponding to the measurement data to execute a correction calculation for the measurement data; A temperature measurement method using a thermosensor, characterized in that (1) it outputs corrected measurement data according to the method.