JP2003035607A - Thermocouple thermometer and ceramic furnace - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inexpensive thermocouple thermometer capable of measuring a high temperature of about 1,000 deg.C or higher, and a ceramic furnace having the thermocouple thermometer arranged thereto. SOLUTION: The thermocouple thermometer 10 includes a thermocouple 12, a detection means 14 for detecting the electromotive force of the thermocouple 12, a conversion means 16 for converting the electromotive force into the temperature value corresponding to the electromotive force detected by the detection means 14, and a correction means 18 for correcting the temperature value by predetermined operation. The temperature value is corrected by a method for converting the measured temperature value into a preliminarily stored temperature value. The ceramic furnace 22 is constituted so as to include the thermocouple thermometer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermocouple thermometer for correcting a temperature value measured by a thermocouple and a kiln equipped with the thermocouple thermometer.

[0002]

2. Description of the Related Art A kiln for pottery is commercially available for individuals who enjoy pottery. This kiln is one in which molded clay is put and fired. The temperature for firing is high, for example, about 1200 ° C. or higher. A thermocouple thermometer is used as the thermometer in the kiln. Thermocouples generate electromotive force by joining two ends of two kinds of metal wires and making both contacts different temperatures. Further, the thermocouple thermometer knows the temperature from its electromotive force. There are various combinations of the two types of metals that form the thermocouple. R thermocouple of platinum and platinum rhodium can measure up to about 1600 ℃. In addition, R is a symbol of the thermocouple type at the International Electrotechnical Commission.

[0003]

However, platinum is expensive and the thermocouple thermometer is expensive, which is a factor of raising the cost of the kiln. Therefore, it is conceivable to use a thermocouple using a material other than platinum. For example, chromel (10% chrome, remaining nickel) and alumel (aluminum,
A K thermocouple in which a small amount of manganese, silicon, etc., and the balance nickel) is combined is conceivable. Note that K is a symbol for the type of thermocouple used at the International Electrotechnical Commission. The price of K thermocouple is
It is about one-tenth of the R thermocouple using platinum. However, although the price of the thermocouple can be reduced, at a temperature of about 1000 ° C. or higher, temperature measurement cannot be performed due to the characteristics of chromel and alumel. Therefore, it cannot be used as a thermometer for a kiln for pottery.

An object of the present invention is to provide an inexpensive thermocouple thermometer capable of measuring a high temperature of about 1000 ° C. or more, and a kiln equipped with the thermocouple thermometer.

[0005]

The gist of the thermocouple thermometer of the present invention is that the thermocouple disposed at the first position, the detecting means for detecting the electromotive force of the thermocouple, and the detecting means. It includes a conversion unit that converts the temperature value corresponding to the electromotive force, and a correction unit that corrects the temperature value to the temperature value at the second position by a predetermined calculation.

The predetermined calculation includes converting the temperature value at the first position into a temperature value at the second position corresponding to the temperature value, or adding to the temperature value.

The gist of the kiln of the present invention includes a heating chamber formed of a heat-resistant member in a box shape, and the thermocouple thermometer according to claim 1 or 2 for measuring the temperature in the heating chamber. .

Further, in the kiln, at least two heat-resistant rod-shaped members arranged so as to penetrate the heat-resistant member from the outside to the inside of the heating chamber and the rod-shaped members are connected to each other inside the heating chamber, A linear member that generates heat when a voltage is applied, and a heating unit that applies a voltage between the rod-shaped members including the linear member outside the heating chamber to heat at least the linear member. Including.

At least one of the at least two heat-resistant rod-shaped members is hollow from the outside of the heating chamber to a predetermined position inside the heat-resistant member. Further, the tip of the thermocouple passes through the hollow of the rod-shaped member and is connected to the rod-shaped member at the predetermined position.

The thermocouple thermometer includes a detection means for detecting a break in the linear member by detecting a temperature change in the linear member or a change in electromotive force generated in the thermocouple.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a thermocouple thermometer and a kiln according to the present invention will be described with reference to the drawings.

As shown in FIG. 1, a thermocouple thermometer 10 of the present invention includes a thermocouple 12 arranged at a first position and a thermocouple 1.
Detecting means 14 for detecting the electromotive force of No. 2 and conversion means 1 for converting into a temperature value corresponding to the electromotive force detected by the detecting means 14.
6 and a correction unit 18 that corrects the temperature value at the second position by a predetermined calculation.

It also includes a display means 20 for displaying the temperature value corrected by the correction means 18. The display means 20 is
Includes liquid crystal devices. It is possible to provide a compensating lead wire between the thermocouple 12 and the detection means 14 as needed. The compensating lead wire is a lead wire for connecting the thermocouple 12 and the detecting means 14 when the thermocouple 12 and the detecting means 14 are arranged at positions separated from each other. There is a method in which a metal wire of the same type as the thermocouple 12 is used, or a metal in which electromotive force of the thermocouple is generated is used as a substitute under the temperature condition at the position where the compensation lead wire is used.

The thermocouple 12 used in the present invention is preferably a K thermocouple. The K thermocouple 12 is a thermocouple in which a combination of two metal wires is a combination of chromel (10% chromium, remaining nickel) and alumel (a small amount of aluminum, manganese, silicon, etc., remaining nickel). K thermocouple 12 is 1
Accurate temperature measurement is possible under the temperature condition of 000 ° C or less as compared with other thermocouples. Moreover, the price is about 1/10 of that of the R thermocouple using platinum.

The detection means 14 detects the electromotive force generated in the thermocouple 12, as in a general thermocouple thermometer. The conversion means 16 is means for converting the electromotive force into a temperature value. The electromotive force generated is determined by the type of thermocouple 12 and the temperature difference between the contacts x and y of the thermocouple 12.

Due to the nature of the metal wire used for the K thermocouple 12,
It cannot be measured above about 1000 ° C. Therefore,
The correction means 18 is for correcting the temperature value detected by the K thermocouple 12 at the first position to the temperature value at the second position where the temperature measurement is desired. For example, as shown in FIG.
The thermocouple 12 is placed at a first position (point A) below 00 ° C. to measure the temperature, and the correcting means 18 corrects the temperature at the second position (point B) at which the temperature measurement is desired. From the above, the thermocouple 12 is arranged at the position (point A) where the temperature can be measured, not at the point B at which temperature measurement is desired.

The correction performed by the correction means 18 is performed by the K thermocouple 12.
Is to convert the temperature value measured by the method into a predetermined temperature value. The predetermined temperature value is the thermocouple 1
2 is the temperature at the desired position (second position: point B) to be measured with respect to the temperature value at the position to be measured (first position: point A). The correction means 18 can perform the above conversion,
Each temperature value and a predetermined temperature value corresponding to each temperature value are stored in association with each other. In storing the temperature at the point B, the temperature at the point B cannot be measured by the K thermocouple. Therefore, by simultaneously measuring the temperatures of the B point and the A point with the R thermocouple and the K thermocouple, respectively, and obtaining the correlation between the temperatures of the B point and the A point, the temperature value of the B point corresponding to the A point is obtained. Can be memorized.

The temperature measurement using the thermocouple thermometer 10 will be described. The temperature to be actually measured is B shown in FIG.
The temperature at the point is 1000 ° C. or higher. But K
Since the thermocouple 12 cannot measure a temperature of about 1000 ° C. or higher, the temperature is 100
The K thermocouple 12 is installed at point A at a temperature of 0 ° C. or lower. The K thermocouple 12 generates an electromotive force, and the detection means 14 detects the electromotive force. The conversion unit 16 converts the temperature value corresponding to the electromotive force.

However, since the temperature value at the point A is not the temperature value at the point B as it is, the correction means 18
But make corrections. The correction method is a method of converting the temperature value of the point A obtained by the measurement into the corresponding temperature value of the point B. This is because the correction means 18 refers to the temperature value obtained by the temperature measurement at the point A and converts it into the temperature value at the point B corresponding to the stored temperature value at the predetermined point A. Is. By this correction, the temperature value at point A is converted to the temperature value at point B. The corrected temperature value is displayed on the display means 20.

As described above, when the thermocouple thermometer 10 of the present invention is used, it is possible to measure the temperature of 1000 ° C. or higher with the inexpensive K thermocouple 12 without using the expensive R thermocouple using platinum.

Next, a kiln 22 using the thermocouple thermometer 10 of the present invention will be described. As shown in FIGS. 3 (a) and 3 (b), the kiln 22 of the present invention includes a heating chamber 26 formed of a heat-resistant member 24 in a box shape, and the above-mentioned thermoelectric device for measuring the internal temperature of the heating chamber 26. And a thermometer 10. Heat resistant member 2
Reference numeral 4 is a refractory brick or a fireproof insulating brick.

Further, the kiln 22 has at least two rod-shaped members 28 which are arranged so as to penetrate the heat-resistant member 24 from the outside of the heating chamber 26, and a linear member which connects the rod-shaped members 28 to each other inside the heating chamber 26. The rod-shaped member 28 including the linear member 30 that connects the member 30 and the rod-shaped members 28 to each other outside the heating chamber 26.
And a heating means 32 for applying a voltage between them to heat at least the linear member 30.

The rod-shaped member 28 is made of a heat resistant material. For example, Kanthal can be used. Further, since a voltage is applied by the heating means 32, a conductive one is used. At least one of the rod-shaped members 28
As shown in FIG. 4, the book is hollow 29 from the outside of the heating chamber 26 to a predetermined position of the heat resistant member 24. In other words, the rod-shaped member 28 is connected to the pipe-shaped member. This is because, as shown in FIG. 4, the tip of the thermocouple 12 is brought into contact with the rod-shaped member 28 at a predetermined position through the thermocouple 12 of the thermocouple thermometer 10. Therefore, the thermocouple thermometer 10 measures the temperature of the rod-shaped member 28 at a predetermined position. This cannot directly measure the temperature of the heating chamber 26 where the K thermocouple 12 is 1000 ° C. or higher. Therefore, the temperature of 1000 ° C. or less transmitted through the rod-shaped member 28 is measured, and the correction unit 18 corrects the measured temperature by the heating chamber 26.
This is because the internal temperature is corrected.

As the linear member 30, a heating wire that generates heat when a voltage is applied is used. The type of heating wire is iron chromium wire, Kanthal wire, platinum wire, molybdenum wire, or the like. It is also possible to provide a plurality of linear members 30 in one kiln 22. In that case, one linear member 30
In contrast, the two rod-shaped members 28 are used, and the linear members 3
A voltage is applied to 0, and one of the rod-shaped members 28 is used for temperature measurement or a disconnection inspection described later. When voltage is applied to the linear member 30 to generate heat, the heating chamber 26
The temperature inside can be raised.

As shown in FIG. 4, at a predetermined position inside the heat-resistant member 24, the hollow 29 of the rod-shaped member 28 is the end point inside. The tip of the thermocouple 12 that has passed through the hollow 29 of the rod-shaped member 28 is connected or contacted with the rod-shaped member 28 at the end point inside the hollow 29. The temperature of the rod-shaped member 28 at a predetermined position of the heat-resistant member 24 is 1000 ° C. or lower.
For example, the predetermined position is a position from the position of 15 mm from the inner wall surface of the heating chamber 26 to the outer wall surface of the heating chamber 26.

The thermocouple thermometer 10 can include a detecting means for detecting the disconnection of the linear member 30 due to the temperature change of the linear member 30. This is because the heating means 32 is the linear member 3
A voltage is applied between the rod-shaped members 28 including 0, the case where the temperature does not rise for a predetermined time is detected, and it is determined that the wire has broken.
Also, when a voltage is applied to the linear member 30 and a rapid temperature drop occurs, it can be determined that the wire is broken. In addition to detecting the disconnection by the change in the measured temperature, the disconnection can be determined by the change in the electromotive force generated in the thermocouple 12.

The kiln 22 of the present invention is used as a general electric kiln because the heating means 32 applies a voltage to the linear member 30 to raise the temperature of the linear member 30 as described above. It

A method of using the kiln 22 will be described. Mold the clay for pottery into a desired shape such as a cup, and heat it in the heating chamber 2
Place inside 6. After closing the heating chamber 26, the power of the heating means 32 is turned on, and the rod-shaped member 2 including the linear member 30.
Voltage is applied between 8. By applying the voltage, the temperature of the linear member 30 rises.

As shown in FIG. 4, at a predetermined position of the heat-resistant member 24 forming the wall of the heating chamber 26, the hollow 2 of the rod-shaped member 28 is formed.
The tip of the thermocouple 12 passing through 9 is in contact with the rod-shaped member 28. The thermocouple thermometer 10 of the present invention shown in FIG. 1 is configured so that the temperature at a predetermined position can be obtained by correction after measuring the temperature at a position deviated from the predetermined position. Therefore, the point B in FIG.
The temperature value measured by the correction means 18 is corrected by setting the point A as the contact portion between the rod-shaped member 28 and the thermocouple 12 in FIG. 4, and the temperature inside the heating chamber 26 (point B) is displayed by the display means 20. To display. In other words, heat is generated by the rod-shaped member 28.
By utilizing the fact that the temperature at each position of the rod-shaped member 28 is different when it is transmitted from inside to outside of the heating chamber, the thermocouple 12 can be measured at a position in the rod-shaped member 28 where the temperature can be measured. The rod-shaped member 28 and the thermocouple 12 are in contact with each other.

Based on the temperature displayed on the display means 20, the clay is fired at a predetermined temperature for a predetermined time to complete the pottery product.

Further, since the linear member 30 used in the kiln 22 of the present invention has a high temperature of 1000 ° C. or higher, it deteriorates and breaks due to long-term use. Therefore, the detection means of the thermocouple thermometer 10 detects the temperature change and the disconnection. That is, if there is no temperature increase within a predetermined time after the heating means 32 starts heating the linear member 30, it is determined that the linear member 30 is broken. In the kiln 22 of the present invention, the thermocouple thermometer 10 and the heating means 32 work together.

As described above, since the kiln 22 of the present invention uses the thermocouple thermometer 10 using the K thermocouple 12, it becomes inexpensive. Even if the temperature cannot be measured by the K thermocouple 12, the desired temperature can be obtained by measuring and correcting the temperature of the heat that has dropped in temperature while being transmitted through the rod-shaped member 28.

Although the embodiments of the thermocouple thermometer and the kiln of the present invention have been described above, the present invention is not limited to the above embodiments of the present invention. For example, although the K thermocouple 12 is used, thermocouples other than the K thermocouple 12 can be used.
There are J thermocouple which is a combination of iron and constantan (45% nickel, remaining copper) and E thermocouple which is a combination of chromel and constantan. In this case as well, since it is not possible to measure the temperature of about 1000 ° C. or higher, as shown above, the temperature at the first position where the temperature is measured by the thermocouple and the second position at 1000 ° C. or higher are measured and the correlation Ask for. This allows the thermocouple thermometer 10 to be used as in the embodiment shown in FIG.

When the temperatures at points A and B in FIG. 2 are affected by the temperature, the temperatures at points A and B at each temperature are calculated and stored in the correction means 18. The correction means 18 is
The temperature at point A is corrected to the temperature at point B with reference to the air temperature and the temperature at point A.

Although the thermocouple 12 and the rod-shaped member 28 were in contact with each other inside the heat-resistant member 24, the heat-resistant member 2 was not contacted with each other.
The tip of the thermocouple 12 may be arranged at an arbitrary position inside 4. Also in this case, the temperature of the contact point of the thermocouple 12 is a temperature at which the thermocouple 12 can measure the temperature, for example,
If it is a K thermocouple, the temperature should be 1000 ° C or lower. Also in this case, the first position and the 100
The temperature at the second position of 0 ° C. or higher is measured to obtain the correlation. Further, the thermocouple 12 is inserted in the hollow 29 of the rod-shaped member 28.
The heat-resistant member 24 was perforated, and the thermocouple 12
The rod-shaped member 28 may be brought into contact with the rod-shaped member 28.

Although the above kiln furnace 22 is intended for an electric kiln, it can also be used for a gas kiln, a kerosene kiln and the like. In using the thermocouple thermometer 10,
Inside the heat-resistant member 24 that constitutes the kiln 22, and 100
The temperature is measured at a position of 0 ° C. or lower, and the correction unit 18 corrects the temperature to a desired temperature.

Although the correcting means 18 of the thermocouple thermometer 10 converts the measured value into a predetermined value, it can be corrected by adding or multiplying the measured value by a predetermined value. In this case, the temperature value at point A in FIG. 2 is corrected to the temperature value at point B by adding or multiplying it by a predetermined value.

In the thermocouple thermometer 10, the temperature at the point B can be measured by measuring the temperature at the point A in FIG. 2, but it can also be measured at the points C and D as shown in FIG. It is also possible to do so. In this case, the temperatures at points C and D corresponding to the temperature at point B are also stored in the correction means 18 in association with the temperature at point B. In this way, by making it possible to select and measure temperature at multiple positions,
It enables flexible temperature measurement.

Although the thermocouple thermometer and the kiln of the present invention have been described above, the present invention is not limited to these. The present invention can be carried out in a mode in which various improvements, modifications and variations are added based on the knowledge of those skilled in the art without departing from the spirit of the present invention.

[0040]

According to the thermocouple thermometer of the present invention, when the temperature cannot be measured due to a high temperature, the temperature is measured by making a correction at a low temperature position apart from the position. It is carried out. Therefore, it was possible to measure a temperature of 1000 ° C. or higher using an inexpensive K thermocouple.

The kiln of the present invention measures the temperature in the heating chamber by the thermocouple thermometer described above, which is less expensive than the conventional kiln. Further, by directly contacting the thermocouple thermometer to the rod-shaped member to which a voltage is applied, it is possible to measure the direct temperature of the linear member, and disconnection of the linear member due to no temperature rise of the linear member. Can be detected.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a thermocouple thermometer of the present invention.

FIG. 2 is a diagram showing a relationship between an actual temperature measurement point and a point at which temperature measurement is desired.

FIG. 3 is a view of a kiln of the present invention, (a) is a sectional view, and (b) is a view of a surface on which a linear member is arranged.

FIG. 4 is a diagram showing a contact point between a thermocouple and a rod-shaped member.

FIG. 5 is a diagram showing temperature measurement at a plurality of positions.

[Explanation of symbols]

10: Thermocouple thermometer 12: Thermocouple 14: Detection means 16: conversion means 18: Correction means 20: Display means 22: kiln 24: Heat resistant material 26: Heating room 28: Bar-shaped member 29: Hollow 30: Linear member 32: heating means

Claims (7)

[Claims] 1. A thermocouple arranged at a first position, a detecting means for detecting an electromotive force of the thermocouple, and a converting means for converting a temperature value corresponding to the electromotive force detected by the detecting means.
A thermocouple thermometer, comprising: a correction unit that corrects the temperature value to a temperature value at the second position by a predetermined calculation. 2. The predetermined operation converts the temperature value of the first position into a temperature value of the second position corresponding to the temperature value, or adds to the temperature value of the first position. The thermocouple thermometer according to claim 1, comprising: 3. A heating chamber formed of a heat resistant member in a box shape,
The thermocouple thermometer according to claim 1 or 2 for measuring the temperature in the heating chamber. 4. At least two heat-resistant rod-shaped members, which are arranged so as to penetrate the heat-resistant member from the outside of the heating chamber, and the rod-shaped members are connected to each other inside the heating chamber, and a voltage is applied. A linear member that generates heat by being heated, and a heating unit that applies a voltage between the rod-shaped members including the linear member outside the heating chamber to heat at least the linear member. The kiln described in 3. 5. At least one of the at least two heat-resistant rod-shaped members is hollow from the outside of the heating chamber to a predetermined position inside the heat-resistant member.
Kiln described in. 6. The kiln according to claim 5, wherein the tip of the thermocouple passes through the hollow of the rod-shaped member and is connected to the rod-shaped member at the predetermined position. 7. The thermocouple thermometer includes detection means for detecting a wire break in the linear member by detecting a change in temperature of the linear member or a change in electromotive force generated in the thermocouple. The kiln according to 4 to 6.