JP2960511B2 - Manufacturing method of multi-wire bundle sliding brush - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method of manufacturing a multi-bundled sliding brush used for small precision equipment such as an encoder and a potentiometer.

(Prior art and problems) Conventionally, in order to make a multi-wire bundle sliding brush, as shown in FIG. 1a, a large number of wire bundles are welded to a spacer, and then cut and formed as shown in FIG. 1b to form a brush. The multi-filamentary sliding brush 8 was formed by resistance welding to the spring material 4 as shown in FIG.

By the way, in the case of a large number of wire bundles, when the wire bundle is wide, it is difficult to obtain parallelism with a flat electrode when welding to a spring material.
As shown in FIG. C, the spacer 2 side was welded at two places with a sharp electrode 7.

However, in this case, the welding strength is stable, but due to the partial pressurization at two places, the deformation due to uneven heat influence on the welded portion causes a vertical step (variation) at the brush tip as shown in FIG. 1d. ) Occurred, resulting in a multi-wire bundle sliding brush 9 having extremely poor dimensional accuracy.

(Object of the Invention) The present invention is to provide a method for manufacturing a multi-wire bundle sliding brush having stable welding strength, no unevenness in the vertical direction at the brush tip, and high dimensional accuracy.

(Constitution) The technical means of the present invention for solving the above problems is a method for manufacturing a multi-wire bundle sliding brush in which a multi-wire bundle is welded to a spacer, cut and formed into a tip brush, and the tip brush is welded to a spring material. In the above, a sharp electrode is brought into contact with the spacer side of the tip brush and welded to the spring material on the multi-wire bundle side, and then a flat electrode is further brought into contact with the spacer side, and the current, voltage, and voltage are applied according to the welding conditions. Welding is performed by reducing the pressure.

(Operation) According to the present invention described above, after the multi-wire bundle side of the tip brush is welded to the spring material with a sharp-pointed electrode, a flatter electrode is brought into contact with the spring material, and current, voltage, and pressure are applied by the welding. Since the welding is made weaker, the unevenness due to uneven heat at the welded portion during the first welding causes a step (variation) in the vertical direction of the brush tip due to deformation. The pressure is corrected by the pressure, so that the step (variation) at the top and bottom of the brush tip is also corrected, resulting in a flat brush tip.
Here, the reason why the second welding condition (current, voltage, voltage) is made weaker than the first welding is that if the welding condition is the same or stronger as the first welding, the current is locally concentrated and abnormal heat is generated, resulting in abnormal heating. This is because welding and fusing occur, and correction can be performed with moderate heat and pressure by performing welding under weaker welding conditions than the first time.

(Examples) Examples and conventional examples will be described below.

Material Ag30% Pd35% Pt10% Au10% Cu14% Zn1% alloy, wire diameter 90μm, 80 multi-wire bundle 1, material CuNi30%, length
9mm, width 1.5mm, plate thickness 0.2mm, projection height 0.1m
m, spacer 2 with projection width 0.2mm and curvature 0.1R
Then, as shown in FIG. 1A, the tip end of the brush is formed in a V-shape to have a curvature of 0.2R to form a tip brush 5 as shown in FIG. Like the material, phosphor bronze, 25mm long, 12mm wide, 0.2mm thick spring material 4 material Cr2% -Cu, flat lower electrode 6 on spring material side, spacer side 5mm outer diameter, sharp cone with sharp tip The first welding was carried out under the welding conditions of a pressing force of 10 kg, a current value of 4 KA and a voltage value of 3 V at two places where the upper electrode 7 having a curvature of 1R and a curvature of 1 R were separated by 4 mm, and as shown in FIG. A moving brush 9 was obtained and used as a conventional example. Then, as shown in FIG. 1e, the material Cr2% -Cu
The electrodes 6, 10 are flat on both the spring material 4 side and the spacer 2 side.
Then, a second welding was performed under the welding conditions of a pressure of 9 kg, a current value of 3 KA, and a voltage value of 2 V to obtain a multi-wire bundle sliding brush 11 as shown in FIG. . Therefore, the results of quality inspections of the examples and the conventional examples are summarized in the following table.

In the conventional example, there were 7 out of 100 defects due to the brush step (variation), the welding strength was average value = 25 kg, and the difference R between the upper and lower limits was R = 12 kg. There was no defect due to the step of the brush (variation), and the welding strength was good, both in dimensional accuracy and welding strength, with the average value = 30 kg, the difference R = 6 kg between the upper and lower limits.

(Effects of the Invention) As is clear from the above results, according to the method of manufacturing the multi-wire bundle sliding brush of the present invention, the step (variation) in the vertical direction of the brush tip at the time of the first welding is reduced by the first welding condition. In the second welding with a flat electrode under welding conditions weaker than (current, voltage, pressurization), deformation due to uneven heat effect at the welded part is corrected by heat and pressure, and the top and bottom of the brush This has the effect that a multi-wire bundle sliding brush having stable welding strength without any step in the direction can be obtained.

[Brief description of the drawings]

1a to 1f are views showing a manufacturing process of a multi-wire bundle sliding brush according to one embodiment of the present invention, and FIG. 2 is a perspective view showing a conventional multi-wire bundle sliding brush.

Claims (1)

(57) [Claims] 1. A method of manufacturing a multi-bundled sliding brush, comprising welding a multi-filament bundle to a spacer, cutting and shaping the multi-filament bundle into a tip brush, and welding the tip brush to a spring material. After the electrodes are brought into contact and welded to the spring material on the multi-wire bundle side, a flat electrode is further brought into contact with the spacer side, and the current, voltage, and pressure are made weaker than the welding conditions and welding is performed. A method of manufacturing a wire bundle sliding brush.