JPH0125012B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a flexible, vibration-resistant high-temperature resistance temperature detector and a method for manufacturing the same, and its object is to use a conventional standard type inorganic insulating powder. Resistance thermometers filled with powder lack vibration resistance due to powder filling, and air existing between the protective tube and the element tends to cause time delays and lack responsiveness. In addition to improving defects such as self-heating of the resistor element due to electric current, which led to a decrease in accuracy, we have also improved the demand for high-temperature resistance thermometers, which has excellent dynamic response. The present invention aims to provide a vibration-resistant high-temperature resistance temperature sensor and an extremely simple manufacturing method.

The present invention stores a resistance element for high temperature measurement connected to the lead wire of an insulated cable in the core of a metal tube of a required length, connects the metal tube to a cable-sheathed metal tube, and then connects the insulator to the open end of the metal tube. Powder is filled into the gap until the lead wire connection part and the element are partially or completely buried, and this is heated from the outer periphery of the metal tube, for example, by high frequency heating. When this solidifies and the element and connection part are fixed, further metal The open end of the tube is filled with one or a combination of metal powder or insulating powder, and after completing the heating and solidifying stage again, the open end is closed with a plug.

The method of high-frequency heating and melting of the contents of a metal pipe of the present invention includes, for example, installing a metal pipe in the center of a coil, and passing a high-frequency current through the coil to generate a magnetic field around the coil. Eddy current loss generated on the surface generates Joule heat, and due to the heat transfer effect of the metal pipe, if there is metal or insulating powder inside the metal pipe, it is heated and inside the metal pipe. The present invention is carried out by utilizing the phenomenon of melting from the closest part toward the center, but according to this method, the element is simply immersed in molten metal and fixed after the metal solidifies. In contrast, it is possible to fill the area around the high-temperature element with metal powder or insulating powder and then heat and melt it at a variable temperature. It is capable of melting body powder.

Next, an embodiment of the present invention will be described with reference to the drawings. The end portion of the sheathed metal tube 3 of an insulated cable filled with a known flexible inorganic insulating powder 5 of a required length is cut off to form a plurality of leads. Wire 4... is exposed (see Figure 1), and multiple lead wires 2... of a separately prepared high-temperature resistance temperature sensor (for example, a ceramic-encapsulated platinum resistance temperature sensor) are connected to lead wire 4...
Connect to 7 (see Figure 2).

This is installed in a protective metal tube 6 having the same diameter as the cable exterior metal tube 3 so that the element fits into the core of the tube, and one end of the metal tube 6 and the cable exterior metal tube 3 are connected by welding or the like 7' (See Figure 3).

An insulating powder 8 having a melting point and softening point that does not thermally affect the characteristics of the high temperature element 1, such as glass powder, is filled from the open end 6' of the metal tube 6 to the extent that the lower end of the element 1 is buried (see Fig. 4). ), high-frequency heating 9 is applied from the outer periphery of the metal tube 6 using a high-frequency heating device (not shown) with adjustable output to melt the glass powder 8 inside the metal tube 6 at a required temperature (see Figure 4), and the molten glass is connected to the lead wire. After filling the gap between the connecting portion 7 and the lower part of the high-temperature element 1 and the metal tube 6, solidification 10 is performed to fix the element 1 and the lead wire connecting portion 7 (see FIG. 5). Next, the space above the metal tube 6 is filled with metal powder 11 having a melting point that does not affect the wires of the high-temperature element (for example, metal powder containing nickel wax or cement powder) up to the upper end of the metal tube 6, and the metal powder is heated again by high frequency heating 9. Melt 11 (see Figure 6)
At the same time, the molten metal fills the gap between the element 1 and the metal tube 6 and solidifies 12 to fix the element 1 (see FIG. 7).

Finally, as shown in FIG. 8, a metal plug 13 made of the same material as the metal tube 6 is inserted into the open end 6' of the metal tube 6, opened, and fixed 14 by welding or high-frequency brazing, etc., as shown in FIG. A resistance temperature detector having the configuration shown in is obtained.

As another example, depending on the object to be measured, the first
The second half of FIG. 6, FIG. 7, and FIG. 8 of the example are omitted, and the metal powder (for example, nickel powder) is firmly filled in the upper part of the vitrified portion 10 in the metal tube 6, and then the metal tube is opened. A metal plug 13 is inserted into the end 6', closed, and welded or brazed.

In addition, as another example, depending on the measurement target,
As shown in the explanatory views of FIGS. 10 to 16, the steps up to FIG. 3 of the first embodiment are the same, and in the first half of FIG. Fill it up to 100%, solidify it by high frequency heating 9, etc. as shown in Figure 14, fix the lead wire connection part 7 and element 1, insert and close the plug into the open end 6', and fix it by welding or brazing, etc. 16th
Obtain the product as shown in the figure.

In addition to the above-mentioned embodiments, the present invention is not limited to the described embodiments; instead, the metal tube 6, the element 1, and the lead wire connection part 7 are integrated and insulated, and the upper part of the metal tube 6 is used for heat transfer. Needless to say, in order to firmly fix the element 1 with a highly effective gap filler, a method of heating and solidifying with high frequency or the like can be employed.

Since the present invention is configured and manufactured as described above, the connecting portion 7 between the lead wire 2 of the high temperature element 1 and the lead wire 4 of the insulated cable is integrated with the metal tube 6 through a solid insulating material. Since it is insulated and fixed, there is no risk of disconnection or short circuit due to vibration, etc.
The vibration resistance is improved, and since the gap between the element 1 and the metal tube 6 is integrated with one or a combination of metals or insulators, the heat transfer effect is increased, time delay is reduced, and dynamic response is improved. Since the gap between the element 1 and the metal tube 6 is filled with one or a combination of metals or insulators,
It has an excellent heat dissipation effect against self-heating of the element 1 due to the measurement current, reduces measurement errors and improves accuracy, and uses a high-temperature wave heating method from the outer periphery of the metal tube as a means of melting the filler. Since the material can be melted from the inner side of the tube toward the center, and the melting temperature can be variably adjusted and stopped, the influence on the element 1 installed in the metal tube core can be significantly reduced. The gap between the metal tube 6 and the element 1 is filled with a powder that easily fills the gap, and by heating it, it completely solidifies and fills the gap as an integral piece, firmly fixing the element 1. Can be fixed. Further, even if the filler shrinks due to solidification, secondary filling is very easy, and since the open end 6' is closed by the metal plug 13, temperature sensing at the tip of the element 1 is possible.

Due to the above-mentioned effects, the present invention is industrially advantageous since it is possible to easily obtain a temperature sensing resistor for high temperature measurement with good vibration resistance, accuracy, and responsiveness.

[Brief explanation of drawings]

The drawings illustrate the implementation of the invention, and
Figure 1 is a cross-sectional view of the cable, Figure 2 is a cross-sectional view of the connected elements, Figure 3 is a cross-sectional view of the element shown in Figure 2 with a metal tube fitted over it, and Figure 4 is the insulation shown in Figure 3. Figure 5 is a cross-sectional view of the solidified powder shown in Figure 4, and Figure 6 is a cross-sectional view of the solidified powder shown in Figure 5 when it is filled with metal powder and heated. 7 is a cross-sectional view of the powder shown in FIG. 6 in a solidified state, FIG. 8 is a cross-sectional view of the state with a metal plug inserted at the tip, and FIG. 9 is a cross-sectional view of the above first embodiment.
Figure 10 is a cross-sectional view of the cable of the third embodiment;
The figure is a cross-sectional view of the element connected, and Figure 12 is a cross-sectional view of the element shown in Figure 11 when a metal tube is fitted onto the outside.
Figure 13 is a cross-sectional view when the gap is filled with insulating powder and heated, Figure 14 is a cross-sectional view of the powder in Figure 13 solidified, and Figure 15 is the same as Figure 14 with a metal plug inserted. FIG. 16 is a sectional view of the third embodiment. 1... High temperature element, 2... Lead wire, 3... Exterior metal tube, 4... Lead wire, 5... Inorganic insulating powder, 6... Metal tube, 6'... Open end, 7... Connection Part, 7'... Connection, 8... Insulator powder, 9... High frequency heating, 10... Solidification, 11... Metal powder, 1
2...solidified, 13...metal plug, 14...fixed.

Claims (1)

[Scope of Claims] 1. An insulated cable in which the tip of a lead wire is partially exposed and sheathed with a metal tube, a high-temperature resistance temperature sensor connected to the lead wire of the cable, and a resistance temperature sensor with the resistance temperature sensor removed. a metal tube that is fitted and connected to the exterior metal tube of the insulated cable; a filling that is obtained by filling a gap around the lead wire connection portion inside the metal tube with insulating powder and solidifying it after heating and melting; The remaining void in the tube was filled with one selected from metal powder or insulating powder, or a combination thereof, and after heating and melting, the solidified filling was used to close the open end of the metal tube fitted over the resistance element. A vibration-resistant high-temperature resistance temperature detector consisting of a metal plug and a metal plug. 2. The insulator powder filled in the lead wire connection part is
The vibration-resistant high temperature resistance thermometer according to claim 1, which has a melting point and a softening point that do not affect the high temperature resistance temperature measurement element. 3. The vibration-resistant type according to claim 1 or 2, which uses metal powder with a melting point and softening point that does not affect the high-temperature resistance temperature sensor as a material to fill the remaining space of the metal tube. High temperature resistance thermometer. 4 Connect the lead wire of the high-temperature resistance temperature measuring element to the lead wire of the insulated cable whose end has been cut off and exposed, and connect one end of the metal tube fitted over the temperature measuring resistance element to the outer metal tube of the insulated cable. Connect to the end and fill the gap around the lead wire connection part with insulator powder, heat it from outside the metal tube to melt and solidify it, and then fill the remaining gap with insulator powder or A method for producing a vibration-resistant high-temperature resistance temperature detector, which is filled with one or a combination of metal powders, heated from the outside of the tube, melted, and solidified, and a metal plug inserted and fixed at the end of the metal tube. 5. A method for manufacturing a vibration-resistant high-temperature resistance thermometer according to claim 4, which uses a high-frequency heating method as the heating method. 6. Connect the lead wire of the high temperature resistance thermometer element to the lead wire of the insulated cable whose end has been cut off and exposed, and connect one end of the metal tube fitted over the temperature measurement resistance element to the outer metal tube end of the insulated cable. Vibration-resistant high-temperature resistance temperature detector made by connecting the metal tube to the end of the metal tube, filling the internal void with insulating powder, heating it from the outside, melting it, and solidifying it, and then inserting a metal plug into the end of the metal tube and fixing it. manufacturing method.