JPH09306249A - Heat resistant wire and method for treating terminal thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat resistant wire whose terminal can be rapidly and surely treated. SOLUTION: In an insulating cover 15 of a heat resistant wire 10 which includes a glass-fiber brading 13, a fused part 16 which is formed by heating a portion with a hydrogen flame 20 the glass fibers 12 are fused together to form into a terminal, after which the insulating cover 15 is cut at the fused part 16. Alternateily, the required part of the insulating cover 15 is cut in advance and this cut end is thermally fused. Thus, the terminal of the heat resistant wire 10 can be treated rapidly by simple heating with the hydrogen flame 20 in a short time, and the wire is in no danger of being untwisted since the glass fibers 12 are fused together.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat-resistant electric wire and a terminal treatment method thereof, and a heat-resistant electric wire in which an insulating coating for covering the conductive wire is formed from glass fibers such as a glass fiber bundle (glass fiber tape) or a glass fiber braid. Regarding

[0002]

BACKGROUND ART A general electric wire that uses a material such as vinyl coating or rubber as the material of the insulation coating has an insulation coating of 18
It softens or deteriorates at a temperature of about 0 ° C. Further, under such temperature conditions, even if an insulating coating made of a polyimide-based heat-resistant plastic is used, there is concern about long-term use. For these electric wires, the electric wires in which the materials of the insulating coating and the conductive wire are changed so that they can be used stably in a higher temperature region can be called heat resistant electric wires. As an insulating coating for such heat-resistant wires, a glass fiber braid woven with glass fibers is often used to maintain heat resistance.
In particular, it is preferably used as a high temperature temperature sensor for measuring the combustion temperature of exhaust gas of a combustion device. However,
The insulating coating made of a glass fiber braid is liable to be loosened at its ends, and thus a terminal treatment is required to make it difficult to loosen.

FIGS. 7 (A) and 7 (B) show heat-resistant electric wires which are end-treated by a conventional method. Figure 7
In (A), the heat-resistant electric wire 100 includes a conductive wire 101 made of nickel and an insulating coating 102 of a glass fiber braid formed by knitting fibers of quartz glass. In this heat resistant electric wire 100, the insulating coating 102 is formed by using the glass thread 103.
The terminal treatment is performed by bundling the portions to be the terminals and cutting and removing the insulating coating 102 at the tip of the binding portions. Here, as a method of binding the glass thread 103, a method similar to the method of binding the fishing line to the fishing hook is used. On the other hand, in the heat resistant electric wire 100 shown in FIG. 7 (B), a polyimide heat resistant varnish having an adhesive property is impregnated into the end portion of the insulating coating 102 to form the glass fiber fixing portion 104. The terminal treatment is performed by cutting and removing the insulating coating 102 at the tip including a part of the fixing portion 104. That is, since the glass that is the material of the insulating coating 102 is chemically and thermally more stable than the conductive wire 101, when chemicals or heat is directly applied to the conductive wire 101,
The conductive wire 101 may be invaded before the insulating coating 102. Therefore, conventionally, as described above, the insulating coating 102 is used.
Treatment methods for fixing or sticking have been used.

[0004]

However, in the terminal treatment method in which the glass yarns 103 are bound, the glass yarns 103 to be bound are easily broken, resulting in poor workability. In particular, when the diameter of the insulating coating 102 is reduced to, for example, 2 mm or less, workability is further deteriorated. Further, since the glass thread 103 is fixed only by the frictional force, there is a concern that the binding force will be lost if it shifts. Further, in the terminal treatment method of fixing with a polyimide-based heat-resistant varnish, there is a problem that the polyimide-based varnish is decomposed at a temperature of 500 ° C. or higher and the insulating property of the insulating coating 102 is deteriorated. Moreover, since the fixing force is lost even at the decomposition temperature or lower, the practical upper limit temperature is said to be in the range of 300 ° C., and it has been difficult to use in the temperature range higher than that.

An object of the present invention is to provide a heat resistant electric wire and a terminal treatment method for the terminal, which enables terminal treatment to be carried out quickly and reliably.

[0006]

The heat-resistant electric wire of the present invention is a heat-resistant electric wire formed by covering a metal conductor wire with an insulating coating of glass fiber, wherein the glass fibers at the cut ends of the insulating coating are heat-fused to each other. It is characterized by being worn.
In the present invention as described above, the terminal treatment is carried out by heat-sealing the glass fibers, but the work may be carried out quickly by heating the necessary portion of the insulating coating for a short time such as several seconds. In addition, there is no problem that the terminal can be melted by heat-sealing the glass fiber.

Further, one end treatment method of the heat-resistant electric wire of the present invention is a method for producing the above-mentioned heat-resistant electric wire, specifically, by heating the insulating coating in the longitudinal direction, the glass fiber After heat-sealing each other, the insulating coating is cut at this heat-sealed portion.

Another end treatment method of the present invention is characterized in that the cut portion of the insulating coating which has been cut in advance is heated and the glass fibers in the heated portion are heat-sealed to each other. According to the present invention as described above, a heat-resistant electric wire similar to that obtained by the above-described method can be obtained.

[0009]

DETAILED DESCRIPTION OF THE INVENTION A first embodiment of the present invention will be described below with reference to the drawings. However, for the sake of convenience, the heat-resistant electric wires before and after the terminal treatment will be described with the same reference numerals. FIG. 1 is a side view showing a heat resistant electric wire 10 according to the present embodiment which is subjected to terminal treatment. FIG. 2 shows FIG.
FIG. 2 is a sectional view taken along line II-II of FIG. FIG. 3 is a side view showing the heat resistant electric wire 10 after the terminal treatment. 1 and 2,
The heat-resistant electric wire 10 includes, for example, a conductive wire 11 made of nickel,
A glass fiber braid 13 made by knitting glass fibers 12 made of quartz glass; and a glass fiber tape 14 wound between the conductor wire 11 and the insulating coating 15 so as to be entwined with the conductor wire 11. An insulating coating 15 is formed by the glass fiber tape 14. Although not shown, the glass fiber tape 14 is made by bundling a predetermined amount of fibers similar to the glass fibers 12.

In FIG. 3, the insulation coating 1 of the heat resistant electric wire 10 is shown.
The end portion of 5 is a fusion-bonded portion 16 formed by heating. The fused portion 16 is formed by heat-bonding the glass fibers 12 of the glass fiber braid 13 and the glass fibers of the glass fiber tape 14 together, and has a glossy appearance as compared with the other braided portion of the insulating coating 15. Along with
Mechanically hardened. From the fusion-bonded portion 16, the lead wire 11
The cut end is exposed, and the exposed part is connected to equipment such as a high temperature pressure sensor.

Next, a method for treating the end of the heat resistant electric wire 10 will be described with reference to FIG. First, in FIG. 4 (A), the heat resistant electric wire 10 is cut from a reel or the like to a required length and taken out,
Midway position in the longitudinal direction of the heat-resistant electric wire 10 taken out,
That is, the position close to the tip of the heat resistant electric wire 10 is insulated by the insulation coating 1
In order to obtain the end of No. 5, the insulating coating 15 is heated by the hydrogen flame 20 for a short time such as several seconds to form the fused portion 16. At this time, the temperature of the hydrogen flame 20 is adjusted to a temperature near the softening point of the glass fiber 12 forming the insulating coating 15 or the like. After that, as shown in FIG. 4 (B), the right side portion in FIG. Then, the blade 21B cuts and removes the insulating coating 15 on the tip side of the fused portion 16. From the above, the terminal-treated heat resistant electric wire 10 shown in FIG. 3 is obtained.

According to this embodiment, the following effects are obtained. That is, the terminal treatment of the heat-resistant electric wire 10 is performed by partially heat-sealing the insulating coating 15. At the time of heat-sealing, it is sufficient to heat the position to be the terminal for a short time such as several seconds, The working time can be greatly reduced and the terminal processing can be performed quickly.

Therefore, it becomes possible to continuously perform end treatment of many heat resistant electric wires 10, and work efficiency can be remarkably improved as compared with the end treatment of binding with a glass thread. In particular, when the diameter of the insulating coating 15 is as small as 2 mm or less, the heating time becomes shorter,
Workability is further improved.

Further, since the terminal treatment is performed by fusing the glass fibers 12 and the like, the binding portion is not displaced and the binding force is not lost as in the conventional case, and the reliability can be improved. Further, since a polymer material such as varnish is not used, the high heat resistance of each member constituting the heat resistant electric wire 10 can be effectively utilized, and the practical upper limit temperature of the heat resistant electric wire 10 can be expanded.

FIG. 5 is a process diagram for explaining the second embodiment of the present invention, and another method for obtaining the heat resistant electric wire 10 will be described based on this diagram. In the present embodiment, as shown in FIG. 5 (A), in the heat resistant electric wire 10 not subjected to the terminal treatment, the tip end side portion from the position of the insulating coating 15 which is to be the terminal is previously cut and removed by the blade 21B, After that, as shown in FIG. 5B, the cut portion 37 of the insulating coating 15 is heated by the hydrogen flame 20 to form the fused portion 16.

According to the present embodiment as described above, it is possible to obtain substantially the same effects as those of the above-described embodiments. By the way, when the cutting portion 37 is heated so that the glass fibers 12 are not only fused to each other but also the glass fibers 12 are fused to the conductor 11, the excess insulating coating 15 is also fixed to the conductor 11 and removed. It may be difficult to do. However, in this embodiment, since the excess insulating coating 15 is removed before being heated, the glass fiber 12 can be sufficiently heated. Therefore, the required insulation coating 15 is reliably fixed to the conductor wire 11, and the positional displacement of the insulation coating 15 with respect to the conductor wire 11 can be prevented more effectively.

The present invention is not limited to the above-described embodiments, but includes other configurations and the like that can achieve the object of the present invention, and the following modifications and the like are also included in the present invention. For example, in each of the above-described embodiments, the material of the conductive wire 11 is nickel, but other materials may be stainless steel, silver, etc., and may be a material generally used as a conductive wire.

In each of the above embodiments, the material of the glass fiber 12 such as the glass fiber braid 13 and the glass fiber tape 14 is quartz glass, but the material of the glass fiber used in the present invention is as follows. Other than quartz glass, for example, non-alkali glass or the like may be used.

The glass fiber braid and the glass fiber tape are not limited to those formed only of glass fiber. In particular, the glass fiber braid may be manufactured, for example, by impregnating a slight amount of polyimide resin so that the glass fiber is difficult to break and the entire braid is not easily disentangled. In short, the main material is glass fiber, and the present invention can be applied even if a material other than glass is included. Also,
The glass fiber tape is not limited to a bundle of a predetermined amount of glass fibers, and may be, for example, a glass thread wound around a conductor in a spiral shape.

Furthermore, in each of the above embodiments, the insulating coating 15 is composed of the glass fiber braid 13 and the glass fiber tape 14, but the invention is not limited to this.
For example, the present invention includes the case where the insulating coating is formed by only one of the glass fiber braid and the glass fiber tape.

Further, in each of the above-mentioned embodiments, the hydrogen flame 20 is used as the heating means, but it is not necessary to limit to the hydrogen flame 20, and an acetylene / oxygen flame using an electric heater or a hydrocarbon gas is used. In other words, any heating means such as a flame resulting from the combustion of butane gas may be used as long as it can heat, melt, and cool a part of the insulating coating 15 for a predetermined time. However,
If a hydrogen flame is used as in the present embodiment, soot is not generated by the unburned gas during heating because the gas component does not contain carbon atoms. Therefore, it is possible to eliminate the anxiety that the soot adheres to the insulating coating 15 and deteriorates the insulating property. The hydrogen flame also has the advantage that the temperature of the combustion flame can be easily controlled. Further, as a means for heating for a predetermined time, a device or the like that can automatically separate from the flame after a predetermined time may be used.

Furthermore, in each of the above-described embodiments, the wire stripper having the same structure is used as the method for cutting and removing the insulating coating 15. However, particularly as the wire stripper used in the second embodiment, A function of clamping the cut end may be provided in order to prevent the cut end from being loosened even when the predetermined portion of the insulating coating 15 is cut. Alternatively, in addition to the wire stripper, a dedicated jig for previously pressing the portion to be the cut end may be provided, and the jig may be removed after heat fusion is performed. However, in order to cut the insulating coating 15, it is not necessary to use a wire stripper, and another method may be used as long as it is a method of cutting the insulating coating 15 without damaging the conducting wire 11.

In each of the above embodiments, the insulating coating 15 on the tip side of the heat insulating wire 10 is removed after being cut, but such an extra insulating coating is merely shifted to the tip side. May be. In such a case, it is preferable that both ends of the shifted insulating coating are also heat-sealed, and by doing so, it is possible to prevent the insulating coating from unraveling. In addition, such an electric wire may be used by cutting the exposed conductor or may be used without being cut.

Further, in each of the above-mentioned embodiments, the fused portion 16
Although the conductor wire 11 was exposed from the end of the heat-resistant wire, when it is not necessary to expose the conductor wire 11 such as when leaving the tip of the heat-resistant wire for a long period of time without being connected to equipment, etc. It suffices if the insulating coating is heat-sealed so as not to be loosened, and such a case is also included in the present invention.
That is, in the present invention, whether or not to expose the conductive wire after cutting the insulating coating may be appropriately determined in the implementation. In short, it suffices if the ends of the insulating coating are heat-sealed.

By the way, in the first embodiment, since a part of the hardened fusion-bonded portion 16 is crushed by the contact of the blade 21B, glass powder is generated at that time, and this glass powder is cut by the cutting portion 17. May be scattered around and adhere to.
Although this itself does not hinder the function of the heat-resistant electric wire 10, the adhered glass powder may become a dusting substance from the heat-resistant electric wire 10 when it is separated from the adhered portion by vibration or the like. Therefore, when the glass powder is generated, as shown in FIG.
As the next work of (B), as shown in FIG.
At 0, the cutting portion 17 may be reheated for several seconds, for example, and the attached glass powder 18 may be re-fused. By doing this,
Since the glass powder 18 crushed and adhered is re-fused, it is possible to reliably prevent dust generation from the heat resistant electric wire 10. In addition,
At the time of cutting the fusion-bonded portion 16, if a dust collector or the like is used, it is possible to effectively prevent the scattering of the glass powder at the time of cutting, and to suppress the adhesion of the glass powder to the heat-resistant electric wire 10 itself. In addition, according to the second embodiment, after the cutting portion 37 is formed in advance, the hardened fusion bonding portion 16 is cut in order to thermally fuse the cutting portion 37 with the first embodiment. Differently, there is no concern that the glass powder 18 will be produced during cutting.

Further, the present invention is not limited to the one used for a high temperature temperature sensor, but can be used as an electric wire for various other devices.

[0027]

【Example】

[First Example] Here, the specific conditions of the terminal treatment method were set as follows, and the heat resistant electric wire 10 was manufactured based on the first embodiment. Conductor wire 11 ... φ300 μm nickel, melting point: 1455 ° C.
(Material data) Insulation coating 15 ... Softening point temperature: 1300 to 1600 ° C
(Material data) ・ Glass fiber braid 13 (quartz glass fiber 12) ・ Glass fiber tape 14 (quartz glass fiber) Hydrogen flame temperature: around 1500 ° C (φ0.1mm platinum / platinum 13% rhodium bare wire thermocouple used Heating time ... 2 seconds According to the present example, the terminal treatment can be performed quickly and reliably, and the heat-resistant wire 1 that can withstand use at high temperature 1
It was confirmed that 0 can be produced.

By the way, the melting point of the conductive wire 11 is 1455 ° C., while the softening temperature of the insulating coating 15 is 1300 to 1
Since the temperature is as wide as 600 ° C., when the insulating coating 15 having a softening temperature higher than 1455 ° C. is used, the conducting wire 11 may be melted before the insulating coating 15 in the heating process. However, in the present embodiment, the insulating coating 15 has a softening point before the conductive wire 11 reaches the melting point, for approximately the following reasons (a) and (b). It was found that the adjacent glass fibers 12 were always fused without being melted first. From this, it was confirmed that even if the insulating coating 15 having a high softening temperature is used, the practicable heat-resistant electric wire 10 can be reliably manufactured. (A) Since the glass fiber 12 and the like forming the insulating coating 15 have a thickness of several μm, the surface area per unit volume {(surface area) / (volume)} is several tens that of the conducting wire 11 having φ300 μm. The heat received from the hydrogen flame 20 causes the temperature to rise quickly. (B) The conductive wire 11 is protected by the insulating coating 15 so that the hydrogen flame 2
The heat from 0 is difficult to be transferred, and the transferred heat flows to the non-heated portion due to the good thermal conductivity of the metal, so that the temperature of the conductive wire 11 at the heated portion does not reach the melting point.

[Second Embodiment] Next, as a second embodiment,
After impregnating a trace amount of the polyimide resin into the heat-resistant electric wire which has not been subjected to the terminal treatment, the terminal treatment was performed under the same conditions as in the first embodiment. As a result, it was confirmed that it is possible to manufacture a heat-resistant electric wire in which the glass fiber in the finished product is difficult to break and the entire glass braid is not easily unraveled. In addition, when such an insulating coating is heated, a black area of carbonized polyimide resin is generated at the boundary between the heated and non-heated portions of the insulating coating. As a result of measurement, a value of 100 MΩ or more / 500 VDC was obtained, and it was also confirmed that it was practical.

[0030]

As described above, according to the present invention, the terminal treatment of the heat-resistant electric wire is performed by heat-sealing the insulating coating made of glass fiber, so that the treatment work can be performed quickly and reliably. The effect is that you can.

[Brief description of drawings]

FIG. 1 is a side view showing a heat resistant electric wire according to a first embodiment of the present invention which is end-treated.

FIG. 2 is a sectional view taken along line II-II in FIG.

FIG. 3 is a side view showing the heat resistant electric wire subjected to terminal treatment.

FIG. 4 is a process chart for explaining the terminal processing method in the embodiment.

FIG. 5 is a process chart for explaining the second embodiment of the present invention.

FIG. 6 is a side view showing a modification of the present invention.

FIG. 7 is a side view showing a conventional example.

[Explanation of symbols]

 10 Heat Resistant Electric Wire 11 Conductive Wire 12 Glass Fiber 15 Insulation Coating 17 Cutting Section

Claims (3)

[Claims] 1. A heat-resistant electric wire formed by covering a metal conducting wire with an insulating coating of glass fiber, wherein the glass fibers at the cut end of the insulating coating are heat-sealed to each other. Electrical wire. 2. A method for terminal treatment of a heat-resistant electric wire, comprising a metal conductive wire covered with an insulating coating of glass fiber, wherein the insulating coating is heated midway in the longitudinal direction to heat bond the glass fibers to each other. After that, the method for terminal treatment of a heat-resistant electric wire is characterized in that the insulating coating is cut at the heat-sealed portion. 3. A method for terminal treatment of a heat-resistant electric wire, comprising a metal conductive wire covered with an insulating coating of glass fiber, which comprises heating a cut portion of the insulating coating that has been cut in advance, and heating the cut portion. A method for terminal treatment of heat resistant electric wires, characterized in that glass fibers are heat-sealed together.