JPH03291174A - Method for joining wire rods - Google Patents

Abstract

PURPOSE:To easily carry out joining of the wire rods without deviation of a center axis by using a hollow heat resistant and insulating tube as a covering tube to weld the wire rods in this hollow tube. CONSTITUTION:The wire rods 1 to be joined are inserted from both ends of the covering tube 4 and the tips 2 of the wire rods 1 are brought into contact and joined with each other and pushed in till a current can be applied. While the pressurizing force being applied to the wire rods 1, the current is carried to melt the wire rods. While energizing being continued, the wire rods 1 are pushed in by the specified distance and welded with pressure and at a point of time when it becomes difficult to press in these more than that by the pressure of weld metal, energizing and pressurization are stopped to complete welding. After welding is completed and the weld metal is solidified, the covering tube 4 is destroyed and removed by the mechanical impact force of a hammer, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for connecting steel wires, iron wires, etc. by welding.

[Prior Art] Welding of wire rods such as steel wires and iron wires is performed in various fields such as machinery, electricity, automobile industry, and spring manufacturing industry.

A conventional method for welding wire rods will be explained using drawings.

FIGS. 2(a) to 2(d) show a conventional wire rod welding method. In FIG. 2(a), 1 is a wire to be connected, and 2 is a cut end of the wire 1. Next, the second
As shown in Figure (b), the cut ends 2 of the wire rod 1 are opposed and brought into contact with each other. At this time, a pressing force P is applied to the two wire rods 1. Next, as shown in FIG. 2(C), an electric current is passed through the wire 1, and the vicinity of the cut end 2 is melted due to the resistance heat generated by the applied electric current. At this time, a pressing force P is applied to the two wire rods 1, and the two wire rods 1 are pushed in sufficiently excessively to form the melted protrusion 3 as large as possible. Then, as shown in FIG. 2(d), after the melted protrusion 3 is roughly removed using pliers or the like, the surface is finished by sanding or the like.

[Problems to be Solved by the Invention] However, the above-mentioned conventional technology has a problem in that the central axis of the wire tends to shift when the wire is pushed in, which tends to cause the wire to jam. Further, there was also the problem that it was difficult to uniformly file the entire circumference of the melted protrusion 3, and it was difficult to obtain a uniform cylindrical shape. For this reason, only certain skilled workers can make a good connection, which has been an obstacle to the endless production of welding wires and the endless use of welding wires. In order to eliminate line stops in welding processes, especially in the automobile industry, the use of large-capacity welding wire rods called endless packs has recently become popular, but the connection of the wire rods here requires specialized skilled workers. The problem was that it could only be done well, which was a major obstacle to expanding the use of Endless Pack.

In order to solve the above-mentioned prior art, the present invention uses a specific jig to perform welding, thereby making it possible to easily connect the wire rods without misalignment of their central axes, making the welding operation easy and even possible for non-experts. It is an object of the present invention to provide a method for connecting wires that allows for high-quality welding.

[Means for Solving the Problems] In order to achieve the above object, the wire connecting method of the present invention includes:
A method of connecting at least two wires, in which the tip surfaces of the two wires are brought together in a cladding tube made of a heat-resistant and insulating material, and then a current is passed through the two wires to generate the current. The method is characterized in that the vicinity of the tip end surface of the wire, which has started to melt due to resistance heat generation, is pushed a certain distance and welded, and then the cladding tube is removed.

In the configuration of the present invention, the cladding tube is made of ceramic manufactured by sintering at a temperature of 1400° C. or higher using a material containing 70% by weight or more of alumina or zirconia, and the cladding tube It is preferable that the relationship between the inner diameter d3 of the tube and the outer diameter d1 of the wire is d<d3≦1.2d+.

[Function] According to the configuration of the present invention described above, a hollow heat-resistant and insulating tube is used as the cladding tube, and the wire rods are welded inside this hollow tube, so that the connection can be made without misalignment of the center axis. It can be easily implemented.

Further, since the welded portion cannot be thicker than the inner diameter of the cladding tube, sanding is not particularly necessary. Therefore, welding can be performed without requiring any skill.

Furthermore, according to the preferred embodiment of the present invention, the cladding tube can withstand welding temperatures, and the workability can be improved without causing breakage or damage. In addition, the wire rod can move smoothly within the cladding tube, the molten metal at the welded part can be isolated from the atmosphere, and oxidation can be prevented, and the molten metal can be prevented from scattering and the molten metal from becoming enlarged (protruding).

[Example 1] An example of the present invention will be described in more detail below with reference to the drawings.

FIGS. 1A to 1E show an embodiment of the present invention. In FIGS. 1A to 1E, 1 is a wire to be connected, and 2 is a cut end of the wire 1. The cut end may have a tapered tip or be uniformly cylindrical.
It may be thick. Reference numeral 4 indicates a hollow heat-resistant and insulating tube (cladding tube), and reference numeral 5 indicates a welded portion. Since the wire rod 1 is inserted into the tube of the cladding tube 4, it is necessary that the inner diameter d3 of the cladding tube 4 is larger than the wire diameter d1 of the wire rod 1, that is, the relationship d<d3 exists. be.

The cladding tube 4 is preferably made of a material that can withstand the temperature and pressure of the molten wire. For example, in the case of steel wire,
Since it has a melting point of 1300°C to 1400°C, general heat-resistant materials such as silica and bentonite sintered at low temperatures (for example, 1200°C or less), other welding backing materials,
The base material for cartridges for stud welding is not suitable for use. A steel wire with a content of alumina or zirconia of 7.0
It is preferable to use a ceramic manufactured by using 0% by weight or more of a material and sintering at a temperature of 1400° C. or more.

Further, the degree of electrical insulation of the cladding tube 4 is sufficient as long as it has normal insulation (for example, a specific resistance of Ω·cm or more) that does not interfere with welding due to resistance heat generation of the steel wire.

In the welding operation, the wire rods 1 to be connected are inserted from both ends of the cladding tube 4 (FIG. 1(A)).

At this time, the central axes of the wires necessarily coincide.

Next, the tips 2 of the wire rods 1 are brought into contact with each other and joined together, and the wires are pushed in until a current can be applied (see Fig. 1 (B).
).

Next, a current is applied to the wire 1 while applying a pressure P, and the wire is melted by the applied current. Then, while continuing to energize, push the wire 1 a certain distance (X) to make pressure contact.
When the pressure of the molten metal makes it difficult to push it any further, stop the current supply and stop applying pressure to finish welding (
Figure 1 (C)).

After welding is completed and the molten metal has solidified, the cladding tube 4
and are destroyed and removed using a mechanical impact force such as a hammer (Fig. 1 (D)). Finally, the exposed surface of the wire is wiped with a cloth to remove any debris adhering to the cladding tube, and the connection work is completed (Fig. 1 (E)). Even if a special finishing process is performed, it is possible to obtain wire rods with the same wire diameter or less (d2≦d+) by slightly scraping the solder or mechanical crimping.

In particular, when the wire is a welding wire, the diameter d2 of the connection finished as described above is 1.2 of the original wire diameter d1.
It is preferable to make the welding contact tip less than twice that.

Also, the inner diameter d3 of the cladding tube and the outer diameter d of the wire rod.
The relationship with 1 is preferably a,<d3≦1.2d. This allows the wire to move smoothly within the cladding tube, isolates the molten metal at the welded part from the atmosphere, prevents oxidation, etc., and prevents the molten metal from scattering and from expanding (protruding). Because you can.

In particular, in the case of welding wire rods with a diameter of 2.0 mm - 0.6 mm, the gap between the inner surface of the cladding tube and the surface of the wire rod is 0.1 d+ ~
It is preferably in the range of 0.2d+. In this range, welding wire rods contain Si and Mn as deoxidizing agents during metal melting.

Since it contains an appropriate amount of AI, etc., if the gap between the inner surface of the cladding tube and the surface of the wire rod is sufficiently small (0.1d+ to 0.2d+), a good weld can be achieved simply by the atmospheric shielding effect of the heat-resistant cladding tube. is obtained.

Furthermore, when welding wire is used in a welding torch, the gap between the welding torch's contact tip and the wire is generally 0. Since it is in the range of 1 to 0.degree. 2d+, it is preferable to set the inner diameter of the cladding tube within this range because the connected welding wire can pass through the contact tip during use.

The method of the present invention is also useful for connecting common wire rods such as steel wires, iron wires, and welding wire rods.

According to the embodiment of the present invention described above, there are the following advantages.

■ Connections can be easily made without any misalignment of the central axis of the wire without requiring any skill.

■ If the wire is for welding, the diameter of the welded part is not larger than the average diameter of the wire other than the welded part, and the contact tip of the welding torch can be smoothly energized by sliding.

■ Since sanding is not required and no protruding parts are formed, accidents caused by forgetting to sand can be prevented.

[Effects of the Invention] According to the present invention described above, a hollow heat-resistant and insulating tube is used as a cladding tube, and wire rods are welded inside this hollow tube, so that a connection without center axis deviation can be achieved. can be easily implemented. Further, since the welded portion cannot be thicker than the inner diameter of the cladding tube, sanding is not particularly necessary. Therefore, it is possible to achieve the excellent effect of being able to weld without requiring any skill.

Furthermore, according to the preferred embodiment of the present invention, the cladding tube can withstand welding temperatures, and the workability can be improved without causing breakage or damage. In addition, the wire rod can move smoothly inside the cladding tube, the molten metal at the welded part is isolated from the atmosphere, preventing oxidation, etc., and it also prevents the molten metal from scattering and from enlarging (protruding) the molten metal. Excellent effects can be achieved.

[Brief explanation of the drawing]

FIGS. 1(A), (B), (C), (D), and (E) are cross-sectional views showing the wire connection process of one embodiment of the present invention, and FIG.
a), (b), (C), and (d) are cross-sectional views showing the conventional wire connecting process. DESCRIPTION OF SYMBOLS 1... Wire rod, 2... Cut end of wire rod, 4... Hollow heat-resistant and insulating tube (cladding tube), 5... Welded part,
10.11... Welded wire rod, 12... Welded part. wE2rE: i 3... Melted protrusion

Claims (2)

[Claims] (1) A method of connecting at least two wires,
In a cladding tube made of heat-resistant and insulating material, the end surfaces of the two wires are brought together, and then a current is passed through the two wires, and the end surfaces of the wires begin to melt due to the resistance heat generated by the applied current. Push the area a certain distance and weld it, then
A method for connecting wires, characterized in that the cladding tube is removed. (2) The cladding tube is made of ceramic manufactured by sintering at a temperature of 1400°C or higher using a material containing 70% by weight or more of alumina or zirconia, and the inner diameter d_3 of the cladding tube is The method for connecting wire rods according to claim 1, wherein the relationship with the outer diameter d_1 of the wire rod is d_1<d_3≦1.2d_1.