JPS5997025A - Thermocouple structure body - Google Patents

Abstract

PURPOSE:To obtain a thermocouple construction body excellent in the response and the durability suitable for measurement of temperature of exhaust gas from an aircraft engine by inserting one thermocouple element into the other pipe- shaped thermocouple element with a large anticorrosivity through an insulator with one end of both the elements put together as detection end. CONSTITUTION:One thermocouple element 12 is made in a pipe while the other thermocouple element 13 filamentous so as to be inserted thereinto 12 through an insulator (magnetia or the like) 14 and one end of both the elements put together as detection end 15 to form a thermocouple 11. The thermocouple thus obtained is plated into a protective tube 16 through the insulator 17 with the detection end 15 exposed at the end thereof. Otherwise, the detection end 15 is incorporated into the end of the protective tube 16. Especially, a thermocouple construction body excellent in reliability, intensity and the like can be obtained by employing chromel with a large anticorrosivity for the pipe-shaped element 12, alumel for the filamentous element.

Description

[Detailed description of the invention] [Technical field of invention] The present invention relates to thermocouple structures.

[Technical background of the invention and its problems]

For example, a thermocouple structure used to measure the temperature of exhaust gas from an aircraft engine is a thermocouple made by connecting one or more pairs of thermocouple elements and supported by an insulator. However, all thermocouple structures have problems in response, reliability, durability, or strength.

1 to 4 each show a conventionally used thermocouple structure. The thermocouple structure shown in FIGS. 1, 2, and 3 includes a pair of filamentous thermocouple elements 1,
Connect one end of 2 to the detection end 3 and connect the thermocouple to the protection tube 4.
This is inserted into the inside of the insulator 5 and buried in the insulator 5. In the case shown in Fig. 1, the detection end 3 of the thermocouple is connected to the protective tube 4.
The end portion of the insulator 5 is embedded inside the insulator 5. In this case, thermocouple elements 1 and 2 including the detection end 3
Since the end of the sensor is covered with the insulator 5 and does not come into direct contact with the atmosphere, it is not corroded by the atmosphere and has high durability, but on the other hand, the response when measuring outside temperature is poor. There is a problem. On the other hand, the one shown in FIG. 2 is called a grounded type in which the detection end 3 of the thermocouple is connected to the protection tube 4. In this case, the ends of the thermocouple elements 1 and 2 are protected by the protection tube 4, resulting in good durability, and the detection end 3 is in direct contact with the atmosphere, resulting in relatively good response. 4, the protection tube and thermocouple element are not insulated. Therefore, there is a problem in that the measured temperature may be incorrectly indicated by detecting other electrical signals.

Moreover, what is shown in FIG. 3 is a thermocouple element 1 including a detection end 3.
．． The end portion of 2 protrudes from the insulator 5.

In this case, the responsiveness during temperature measurement is good, but since the ends of the thermocouple elements 1 and 2 are in direct contact with the atmosphere, they are easily corroded by harmful gas components contained in the atmosphere, resulting in poor durability. , there is a problem that the degree of insulation between the thermocouple elements 1 and 2 is reduced. Furthermore, the thermocouple assembly shown in FIG. 4 has thermocouple elements 1 and 2 inserted through a plurality of insulators 6. However, in addition to the problems of the thermocouple structure shown in FIG. 3, this configuration also has the problem of low mechanical strength for supporting the thermocouple.

[Purpose of the invention]

The present invention has been made in view of the above circumstances, and provides a thermocouple structure that is excellent in responsiveness, reliability, durability, and strength.

[Summary of the invention]

The thermocouple structure of the present invention is obtained by inserting a wire-shaped thermocouple element into a d'-shaped thermocouple element through an insulator, and connecting one end of the two as a detection end. ] equipped with a thermocouple constructed as follows.

[Embodiments of the invention]

Embodiments of the present invention illustrated in the drawings will be described below.

FIG. 5 and FIG. 6 are a longitudinal cross-sectional view and a cross-sectional view showing an embodiment of the thermocouple structure of the present invention.

In the figure, 11 is a thermocouple, and this thermocouple 11 is a long and narrow one. A tube-shaped thermocouple element 12 and a linear thermocouple element 1
It is composed of 3. These thermocouple elements 12 and 13 are made of two types of metal materials, and one of the pipe-shaped thermocouple elements 12 is made of two types of metal materials to avoid corrosion due to harmful gas components contained in the gas whose temperature is to be measured. Among metal materials, a metal material with excellent corrosion resistance is selected and formed. For example, when the thermocouple elements 12 and 13 are formed from a combination of alumel and chromel, the rib-shaped thermocouple element 12 is formed from chromel, which has excellent corrosion resistance, and the linear thermocouple element 13 is formed from alumel. The wire-shaped thermocouple element 13 is inserted into the pipe-shaped thermocouple element 12 along its axial direction, and an insulator 14 such as magnesia powder is placed inside the wire-shaped thermocouple element 12. The thermocouple element 13 is buried and held inside the insulator 14 and is insulated from the thermocouple element 12 by the insulator 14 . One end of the pipe-shaped thermocouple element 12 is connected to one end of the linear thermocouple element 13 to form a detection end 15 . The thermocouple 11 constructed in this way is made by putting the thermocouple element 13 and the insulator 14 inside the thermocouple element 12, reducing the diameter by rolling or drawing, and then forming the pixel element. 12 and 13 are connected by welding, for example.

In the figure, 16 is a large diameter protection tube made of stainless steel, etc.
Inside this protection tube 16, there is a thermocouple 1 along the axial direction.
1 is inserted. The inside of the protective tube 16 is filled with an insulating powder 17 such as magnesia powder, and the three electric couple 11 is embedded and held in the insulating powder 17 and is insulated from the protective tube 16 by the insulating powder I7. In this case, the detection end 15 of the thermocouple 11 is projected outward from one end surface of the insulating powder 17, that is, one end of the protective tube 16, and the detection end 15 of the thermocouple 11 is
The other end extends outward from the protection tube 16 for connection to a temperature measuring device (not shown). The thermocouple structure configured in this manner has particularly excellent responsiveness. The thermocouple structure is manufactured by putting the thermocouple 11 and the insulator 17 inside the protective tube 16 and integrating them by rolling or drawing.

The thermocouple structure is installed at the exhaust port of an aircraft engine, for example, and measures the temperature of the exhaust gas from the engine that passes through this exhaust port. In this case, when the gas comes into contact with the detection end 15 of the thermocouple 11 (that is, the thermocouple element 12.13) protruding from the protection tube 16, the temperature between the thermocouple elements 12.13 An electromotive force is generated.

Therefore, in the thermocouple structure, since the detection end 15 of the thermocouple 1 is made to protrude outward from the protection tube 16, it makes sufficient contact with the gas whose temperature is to be measured to obtain good response. be able to. Moreover, the thermocouple element 1 in the thermocouple 11
2 and the thermocouple element 13 are reliably insulated by an insulator 14, and an insulator 17 is provided between the thermocouple 1 and the protective tube 16.
↓Surely insulated. Thermocouple 11 is a protective tube 16
Because it is insulated, it is not affected by other electrical signals. Therefore, it is possible to prevent erroneous temperature measurement. Moreover, since the pipe-shaped thermocouple element 12 is made of a metal material with excellent corrosion resistance, it will not be easily corroded by harmful components contained in the gas. Note that the other thermocouple cord 13 having a linear shape is connected to the thermocouple element 12 having a pipe shape.
Since it is installed inside the tank, it does not come into direct contact with the gas. The thermocouple 11 has a linear thermocouple element 13 held inside a T4 tube-shaped thermocouple element 12 by an insulating material 14, and the entire structure is integrated, so it can be used as a single thermocouple. Mechanical strength is a dog. Moreover, since the thermocouple 11 is held by insulating powder 17 and installed inside the protective tube 16, the mechanical strength of the entire thermocouple structure is high. Fig. 7 shows the present invention. Another example is shown.

In this embodiment, the detection end 15 is built into the protection tube 16. The durability of such a structure is further improved.

FIG. 8 shows another embodiment of the thermocouple structure of the present invention. In this embodiment, two sets of thermocouples 1 are installed inside the protection tube 16.
1.11' is provided. One thermocouple 11 is provided along the axial direction of the protection tube 16 as in the previous embodiment, and has a detection end 15 protruding outward from one end of the protection tube 16. The other thermocouple 11' is bent in the radial direction of the protection tube 16, and the detection end 15 is inserted into the through hole 1 formed in the peripheral wall of the protection tube 16.
It is located at 8. In this thermocouple structure, the detection ends 15 of each thermocouple 11, 11' are located at different locations, thereby making it possible to measure temperatures at two different locations. This structure is applied when multiple measurements are required. Since the thermocouple element of the present invention can have a smaller cross-sectional area than conventional ones, the structure can be made smaller.

〔Effect of the invention〕

As explained above, the thermocouple structure of the present invention has good responsiveness and excellent reliability, as well as good durability and mechanical strength.

[Brief explanation of drawings]

1 to 4 are longitudinal sectional views showing an example of a conventional thermocouple structure, and FIGS. 5 and 6 are longitudinal sectional views and cross-sectional views showing an embodiment of the thermocouple structure of the present invention, respectively. Area drawing←≠←
FIGS. 8 and 9 are longitudinal cross-sectional views showing other embodiments, and FIG. 10 is a cross-sectional view of the other embodiment shown in FIG. 9. 1.2... Thermocouple element, 3... Detection end, 4... Protection tube, 5... Insulating powder, 11... Thermocouple, 12.1
3...Thermocouple element, 14...Insulation 1%7) Control 5
・"Detection end, 16... Protection tube, 17... Insulating powder. Figure 1 IJ 14 Figure 6 Figure 8

Claims (6)

[Claims] (1) Insert the other wire-shaped thermocouple element inside one pipe-shaped thermocouple element through an insulator, and connect one end of both thermocouple elements as the detection end to create a t-thermocouple. A thermocouple structure comprising: (2) Thermocouple structure 0 according to claim 1, wherein the thermocouple is provided inside a protection tube via an insulator, and the detection end is located at the end of the protection tube. (3) The thermocouple structure according to claim 2, wherein the detection end is exposed to the outside of the protective tube. (4) The thermocouple structure according to claim 2, wherein the detection end is built in a protection tube. (5) The thermocouple structure according to claim 1, wherein the pipe-shaped thermocouple element is made of a metal material that has lower corrosion resistance than the linear thermocouple element. (6) The thermocouple structure according to claim 1, wherein the pipe-shaped thermocouple element is made of chromel, and the linear thermocouple element is made of alumel.