JPH03114682A - Electrode for welding brush wire bundle - Google Patents

Abstract

PURPOSE:To highly stabilize welding strength of a brush wire bundle with respect to base material and further, to suppress burn-through by making the center of a weld zone of an electrode in contact with the brush wire bundle higher than both ends thereof. CONSTITUTION:Punching work is carried out so that the center 8a of the weld zone 8 of a lower electrode 2 in contact with the brush wire bundle 6 is made higher than both ends 8b thereof. This lower electrode 2 is fitted into a recessed part 10 of the upper side of a holder 9 and a screw 12 is inserted from a through hole 11 of the center of the holder 9 and screwed in a tapped hole 2a of the lower electrode 2 for welding and the lower electrode 2 is tightened and fixed thereby. This lower electrode 2 is then set corresponding to an upper electrode 1 and the brush wire bundle 6 formed by lining up and bundling horizontally many brush wires 5 is fed onto the weld zone 8 of the upper surface of the lower electrode 2 and the tip thereof is placed thereon. The base material 4 having a semicircular wire projection 3 is then fed from the other side and the tip thereof is placed on the upper surface of the tip of the brush wire bundle 6 and the upper electrode 1 is lowered and the brush wire bundle 6 and the base material 4 are resistance-welded by pressurizing and energizing of the upper and lower electrodes.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention focuses on horizontally aligning and converging a large number of brush lines in order to make materials for sliding brushes used in trimmers, potentiometers, and many other devices. The present invention relates to an electrode used for resistance welding a brush wire bundle to a base material.

(Prior Art) Conventionally, in order to manufacture a material for a sliding brush, as shown in FIG. The tip of the base material 4 on which the linear protrusions 3 have been formed by pressing is fed, and from the other side, the tip of a brush wire bundle 6 in which a large number of brush wires 5 are horizontally aligned and focused is placed below the tip of the relics 4. Then, as shown in Fig. 3, by pressurizing and energizing both the upper and lower electrodes 1.2, the tip of the brush wire bundle 6 is resistance welded to the linear protrusion 3 at the tip of the base material 4 to form a sliding brush. Manufacturing material 7.

(Problems to be Solved by the Invention) By the way, in the above manufacturing method, heat easily escapes from both ends of the welded portion of the brush wire bundle 6 to the linear protrusion 3, and it is difficult for heat to escape from the center of the welded portion. For this reason, if we suppress the melting in the center of the weld, both ends of the weld will not melt sufficiently and the weld strength will decrease.
Furthermore, if both ends of the weld are sufficiently melted to increase the weld strength, the temperature at the center of the weld will rise too much and bleed will occur. Therefore, the welding strength of the brush wire bundle 6 could not be stabilized. Furthermore, if melting occurs, the brush wire bundle 6 will wave, and the brush wires 5 will come apart in the vertical and horizontal directions, which will not only worsen the appearance of the sliding brush material 7 but also prevent stable contact during sliding. First, we could only produce sliding brushes that generated noise. Furthermore, the lower electrode was damaged by the melting and the life of the electrode was shortened.

Therefore, the present invention makes it possible to obtain a high-quality sliding brush material that is capable of highly stabilizing the welding strength of the brush wire bundle, suppressing melting, and having extremely little variation in the brush wire. The present invention aims to provide a welding electrode for brush wire bundles that can extend the life of the electrode.

(Means for Solving the Problems) The brush wire bundle welding electrode of the present invention for solving the problem 1 is an electrode for resistance welding a brush wire bundle, in which a large number of brush wires are horizontally aligned and focused, to a base material. This is characterized in that the center of the welded part of the electrode in contact with the brush wire bundle is made higher than both ends.

(Function) As described above, in the electrode for welding a brush wire bundle of the present invention, the center of the welded part of the electrode in contact with the brush wire bundle is made higher than both ends. Therefore, during resistance welding between the brush wire bundle and the base material, the contact resistance at the center of the welded part is low (the contact resistance is low at the center of the welded part, and the heat generation between the brush wire bundle and the base material due to the pressurized energization of both the upper and lower electrodes is generated over the entire width). The welding strength is stable, and welding is suppressed.

(Example) An example of an electrode for welding a brush wire bundle according to the present invention will be described as shown in FIG. The front end of the upper surface of the lower electrode 2 made of 0.3 wt% Cu-Cr having a diameter of 5.3 mm and a screw hole 2a at the center is a welded part 8 over a length of 1.5 mm, and the center 8a of the welded part 8 is was punched so that it was 0.044 mm higher than both ends 8b in a chevron shape.

The lower electrode 2 for welding of the brush wire bundle of the example thus obtained is fitted into the recess 10 on the upper surface of the holder 9 as shown in FIG. 2, and the lower electrode 2 was tightened and fixed.

Then, this lower electrode 2 is made of ordinary Cu-Cr0.3wt%.
The lower electrode 2 is set in correspondence with the upper electrode 1 consisting of
On the welding part 8 on the upper surface, from one side, as shown in Figure 2, a wire diameter of 0.07 mm was applied to the
%-Ag30%-Cu 14%-Zn1% A brush wire bundle 6 made by horizontally aligning and converging 65 brush wires 5 is fed, the tips thereof are placed thereon, and then the width is removed from the other end as shown in Fig. 2C. 6. A base material 4 made of nickel silver with a thickness of 0.12 mm and a semicircular linear protrusion 3 with a cross section of 0.1 mm R in the width direction on the lower surface of the tip is fed, and the tip is brushed with a brush wire bundle 6.
Then, the upper electrode 1 is lowered as shown in FIG. A sliding brush material 7 was manufactured by resistance welding to the linear projections 3.

On the other hand, as a conventional example, between the upper electrode 1, which is the same as the embodiment shown in FIG. The tip of the brush wire bundle 6, which is the same as in the embodiment, is fed to the lower side of the tip of the base material 4, and then, as shown in FIG. A sliding brush material 7 was manufactured by resistance welding to the linear protrusion 3 at the tip of the stand trA' 4.

Appearance inspection was performed on each of 1,000 pieces of the sliding brush materials of the example and the conventional example manufactured in this way, and the welding strength was measured. Upon measurement, the results shown in the table below were obtained.

As is clear from the table above, 30% of the conventional sliding brush materials had defective products in which the brush lines were separated by 0.15 mm or more in the downward and horizontal directions, whereas the sliding brush material of the embodiment It can be seen that the quality of the moving brush material is good, with only 5% of such defective products. In addition, the conventional sliding brush material had a low welding strength of the brush wire bundle and was unstable due to large variations, whereas the sliding brush material of the embodiment has a high welding strength of the brush wire bundle (with small variations). It can be seen that it is stable.Furthermore, while the conventional electrode became unusable at 100P, the electrode of the example can be used up to 250P, and it can be seen that it has an extremely long life.

Although the above embodiment deals with the lower electrode 2, it is applied to the upper electrode 1 when the brush wire bundle 6 is fed to the upper side of the stand try'4.

(Effects of the Invention) As mentioned in 1-1 below, according to the electrode for welding brush wire bundles of the present invention, the welding strength of two pairs of brush wire bundles can be made high and stable, and melt bleed can be suppressed. This makes it possible to obtain a high-quality sliding brush material with very little variation in the brush line.Therefore, this sliding brush material can be used to create a sliding brush that can make stable contact during sliding and does not generate noise. Furthermore, since the welding electrode of the present invention can suppress melting of the brush wire bundle during welding, the electrode is less likely to be damaged and its lifespan is extended.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing an embodiment of a welding electrode for a brush wire bundle of the present invention, and FIGS. 2a to 2d are perspective views and side views showing the process of manufacturing a sliding brush material using the welding electrode. 3A and 3B are diagrams showing a conventional method of manufacturing a sliding brush material. 2... Lower electrode, 4... Lines, 5... Brush line,
6... Brush wire bundle, 7... Brush material, 8... Welded part, 8a... Center of welded part, 8b... Both ends of welded part.

Claims (1)

[Claims] 1) Welding of a brush wire bundle characterized in that the center of the welded part of the electrode in contact with the brush wire bundle is made higher than both ends, in an electrode for resistance welding a brush wire bundle in which a large number of brush wires are horizontally aligned and focused to a base material. electrode.