JPH0540104U - Spot welding electrode for binding band - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a spot welding electrode that enables reliable and strong welding by applying a copper band or a copper alloy band to a band used for band-welding type binding equipment. [Structure] The spot welding electrode is mainly composed of molybdenum, an alloy mainly composed of molybdenum, or an electrode composed of a sintered metal mainly composed of molybdenum, or an electrode formed of a copper alloy for the electrode, mainly composed of molybdenum or molybdenum. The electrode is formed by spraying an alloy of.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an improvement of a spot welding electrode for joining a metal band (also simply referred to as a band) at an overlapping portion in a welding-type binding device, and more specifically to a spot welding electrode which enables copper-based band welding. It is one.

[0002]

[Prior Art]

 Conventionally, in spot welding of metals, in the case of a copper alloy having an electric conductivity (IACS) of about 30% or less, it is possible to form a nugget and perform welding, but electric conductivity higher than that. In the case of copper alloys with the properties, it was not possible to join metals with the purpose of welding, that is, with a joining strength, and welding with electrical conductivity of 60% or more was no longer possible. That is, it is known in general spot welding that the weldability of copper alloys for spot welding deteriorates as the electric conductivity increases, as shown in Table 1, and the required welding current also becomes larger than that of steel. Has been.

[0003]

[Table 1]

On the other hand, in the distribution process in the industrial world, banding is generally used to transfer metal products, but for example, bundling of copper tubes, copper electric wires and other copper products is particularly advantageous in terms of maintaining quality. From the above, it has been known that bundling with a copper band, which is a similar metal, is a preferable direction because it has the same physical properties.

From such a background, attempts have been made to bind copper products with copper strips. However, as described above, spot welding of copper is not possible, and therefore, it is not easy to join the overlapped portions of copper strips with a seal. There was no other way but to spoil it. In this seal joining, while using an expensive copper strip, product damage was caused in the seal part, and it was not a satisfactory solution for bundling copper products.

[0006]

[Problems to be Solved by the Invention] In view of the background as described above, the present invention has made an effort to apply welding-based joining that does not cause a scratch to the copper band overlap portion. However, the electric conductivity of copper is higher than 99%, which dissipates heat, the installation of transformers with excessive current and large capacity for this, the metallurgical characteristics of copper, and the limited space conditions of binding equipment. There are many problems to be solved, such as the application in the above, and the inventors of the present invention have made extensive studies and trials, and have reached the solution by selecting and selecting the material of the electrode.

[0007]

[Means for Solving the Problems]

 The present invention has addressed the problems described above by applying the following means. That is, in order to securely and firmly weld copper or copper alloy strips, an electrode formed of molybdenum, an alloy mainly composed of molybdenum, or a sintered metal mainly composed of molybdenum, or a copper alloy for an electrode is used. It was decided to apply this to spot welding of copper strips, as an electrode in which molybdenum or an alloy mainly composed of molybdenum is sprayed on the main part of the formed electrode.

[0008]

[Work]

 The spot welding electrode of the binding band of the present invention (hereinafter simply referred to as this electrode) can be described as the operation as follows. That is, when a copper strip with an electrical conductivity of 99% or more is pressed by the upper and lower electrodes and energized, the copper strip is heated up and down before it is heated by the current flowing through the pressed portion of the copper strip as the body to be welded. The temperature of the electrode rises, and heat is concentrated at the pressurizing point, causing the temperature of the pressurizing part of the copper band to be welded to reach the melting point, and spot welding is performed. A special large capacity transformer is not required to weld the strip, and a transformer for welding the steel strip is sufficient. This is because molybdenum or its alloy or sintered body has a relatively low electric conductivity and a large amount of heat generated by energization, and is suitable as a copper band spot welding electrode. Nothing else. In addition to the copper strip as the welded strip, good welding results are obtained not only for the brass strip.

[0009]

[Examples] Hereinafter, preferred examples of the present invention will be described in detail with reference to the drawings.

As an example of a binding device to which the present electrode 1 is attached and applied, a schematic view of a binding head 5 of a welding type automatic binding machine is shown in a front view in FIG. 1 and a side view in FIG. Is equipped with a welding device 30, a transformer 40, and a copper band feeding and tightening device 50, and the main electrodes 1 are arranged and mounted at the copper band welding points of the welding device 30. The main electrode 1 is composed of an upper electrode 10 and a lower electrode. A pair of 20 is installed.

Although the upper electrode 10 is shown in a front view in FIG. 3 and a bottom view in FIG. 4, it has a screw portion 15 for attaching to an upper electrode holder (not shown), and the tip of the electrode portion 12 is added. The pressure unit 11. The shape is similar to that of a conventional steel strip spot welding electrode.

The lower electrode 20 is shown in a plan view in FIG. 5, a front view in FIG. 6, a bottom view in FIG. 7, and a side view in FIG. It is attached using a screw. The pressing portion 21 is formed on the upper surface of the electrode portion 22.

A structural feature of the present electrode 1 is that molybdenum, an alloy mainly composed of molybdenum, or a sintered metal mainly composed of molybdenum is applied as a constituent material thereof. Molybdenum or an alloy mainly composed of molybdenum is used for the main part of the electrode formed as a material (the electrode part 12 and the pressing part 11 in the upper electrode 10, and the electrode part 22 and the pressing part 21 in the lower electrode 20). It can also be configured by thermal spraying. Here, the alloy mainly containing molybdenum means an alloy containing at least half of molybdenum.

The present electrode 1 made of such a molybdenum-based metal has a difficulty in heating and raising the temperature of the copper strip to be welded by itself, and in addition, even if heat is generated, the diffusion action is strong, and the local action is local. In a situation where spot welding is almost impossible, the electrode 1 is heated and heated by energization, and the amount of heat is concentratedly conducted to the copper band to be welded, leading to welding. Molybden is better than copper. Is also known to have a high melting temperature, and is also known to be used as an electric resistor.

The processing of the main electrode 1 with molybdenum has high hardness, but mechanical cutting is also possible. The electrode 1 made of an alloy mainly containing molybdenum can be sufficiently machined. Further, in the processing of the present electrode 1 using a sintered metal mainly composed of molybdenum, rough forming is possible in the sintering process, and the subsequent mechanical processing becomes relatively easy.

Further, materials such as copper alloys for electrodes such as alumina-dispersed copper, cadmium copper, zirconium copper, nickel copper, chromium copper, cadmium-zirconium copper, nickel-beryllium copper are machined into the upper electrode 10 and the lower electrode 20. Then, when molybdenum or an alloy containing molybdenum as a main component is sprayed on the main portion, the spray amount is preferably about 100 micron to 300 microns.

The present electrode 1 made of molybdenum was applied to weld a copper strip (electrical conductivity of 99% or more, thickness 0.4 mm, width 16 mm, breaking load 173 Kg), and its welding strength was tested. However, the results shown in Table 2 were obtained. This is epoch-making in that the welding of copper strips, which has been regarded as impossible in the past, has been successfully put to practical use and its strength is fully satisfied.

[0018]

[Table 2] Weld zone tensile test results (A) Base material: Copper band size: 0.4 mm x 16 mm Breaking load: 173.0 Kg Welding condition Pressurization: 2.0 Kg / cm ² Current: 3 KA

Further, in the conventional welding of a general brass plate capable of installing a large-capacity transformer, it was possible to carry out a large-current energization, and even in a binding machine, the capacity of the transformer 40 was set to be the same as that of a conventional steel plate. It has been proved that sufficient spot welding can be performed on brass strips as it is for band spot welding. That is, a brass band (electrical conductivity: 30%, thickness: 0.4 mm, width: 16 mm, breaking load 221.2 Kg) is made of an alloy of 97% molybdenum, 2% tungsten, and 1% vanadium. Welding was performed using the electrode 1, and the results of the welding tensile test show extremely good results as shown in Table 3.

[0020]

[Table 3] Weld zone tensile test results (B) Base material: Brass band size: 0.4 mm x 16 mm Breaking load 221.2 Kg Welding conditions Pressurization: 2.0 Kg / cm ² Current: 3 KA

[0021]

[Effect of the device]

 As described above, by implementing the present invention, the welding bundling with the copper strip is achieved in a preferable state, and it is possible only by applying the present electrode to the conventional steel strip bundling equipment, and the copper band welding bundling is desired. It will bring great progress and development to the logistics industry that used to be.

[Brief description of drawings]

FIG. 1 is a front view of a binding head of an automatic binding machine showing a state in which the present electrode is mounted and applied.

FIG. 2 is a side view of FIG. 1, showing a mounting state of the present electrode.

FIG. 3 is a front view showing an upper electrode of the present electrode.

FIG. 4 is a bottom view showing an upper electrode of the present electrode.

FIG. 5 is a plan view showing a lower electrode of the main electrode.

FIG. 6 is a front view showing a lower electrode of the present electrode.

FIG. 7 is a bottom view showing a lower electrode of the present electrode.

FIG. 8 is a side view showing a lower electrode of this electrode.

[Explanation of symbols]

 1 main electrode 5 bundling head 10 upper electrode 11 pressing part 12 electrode part 15 screw part 20 lower electrode 21 pressing part 22 electrode part 25 mounting hole 30 welding device 40 transformer 50 copper strip feeding and tightening device.

Claims (1)

[Scope of utility model registration request] 1. In a spot welding electrode of a banding welding device for binding, in order to securely and firmly weld a band made of copper or a copper alloy, the electrode is molybdenum, an alloy mainly composed of molybdenum, or One of an electrode made of a sintered metal containing molybdenum as a main component or an electrode formed by spraying molybdenum or an alloy containing a molybdenum as a main component on an electrode formed of a copper alloy for the electrode. A spot welding electrode for the banding band.