JPS6315708B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for manufacturing a sliding brush. In recent years, with the development of electrical equipment, a high degree of reliability is required for the electrical contact parts, and it is necessary to improve the reliability of potentiometers and other sliding brushes used in many other products. Therefore, a sliding brush with a large number of wire bundles, that is, a brush that increases the stability of the contact by making multi-point or surface contact has been developed. By the way, in order to manufacture such a brush, as shown in Fig. 1, it is necessary to weld 2 to 100 ultra-fine electrical contact wires 2 with diameters of several microns to several tens of microns to a base material 1, so each electrical contact wire must be It is extremely difficult to weld 2 to the base material 1 in a uniform and stable state. That is, the ultra-fine electrical contact wire 2 is crushed by the pressure applied during welding as shown in FIG. 2, and the wires are crushed together to form a polygonal cross-section and welded, and distortion remains in the wires, as shown in FIG. 3. As shown in figure a, the wire rod 2 has spread outward by about 0.3 mm, and as shown in figure b, the wire rod 2 has spread outward by 0.4 mm.
It is something that spreads apart up and down by about mm. In addition, if the ultra-fine electrical contact wire 2 is only partially welded to the base material 1 due to uneven spacing, or the welded part melts too much, especially if the electrical contact wire 2 is shaped after welding. Electric contact wire 2
may fall off or break. Therefore, the inventor of the present invention made an earnest effort to find a method for manufacturing a sliding brush that can be reliably welded to a base material in a uniform and stable state by aligning a large number of ultra-fine electrical contact wires with equal gaps between them. As a result of our research, we have developed a method that is fully satisfactory. An example of the method for manufacturing a sliding brush according to the present invention will be explained with reference to the drawings. As shown in FIG.
As shown in the figure, a large number of ultra-fine electrical contact wires 2 are arranged horizontally, a base material 1 is arranged on top of the superfine electrical contact wires 2, and resistance welding is performed using an upper electrode 8, and then a large number of electrical contact wires 2 are It is characterized by being molded into a desired shape as shown in Figure 6. In this way, in the method for manufacturing a sliding brush according to the present invention, in resistance welding a large number of extremely fine electric contact wires 2 and the base material 1, a very fine wire 6 is wound around a core metal 5. Since the electrode 7 is used, even gaps are provided between the many ultra-thin electrical contact wires 2, so that the tips of the electrical contact wires 2 do not come apart outwardly or disintegrate up and down due to pressure. The distortion is absorbed and the parts are aligned horizontally left and right, horizontally up and down, and then welded. In addition, even if there is some variation in the spacing between the electrical contact wires 2 when they are supplied, they are all equally spaced and welded by the ultra-fine wire 7 on the outer periphery of the electrode 7, so there may be some spots that are not welded. , the welded part will not melt too much. Therefore, when performing fabrication processing on the electrical contact wire 2 after welding,
The electrical contact wire 2 will not fall off or break. Next, in order to clarify the effects of the method for manufacturing a sliding brush according to the present invention, specific examples and conventional examples thereof will be described. Example As shown in Figure 4, a cylinder with a diameter of 2 mm and a length of 5 mm was prepared.
As shown in FIG. 5, 20 pieces of Pd35w/o- with a diameter of 0.1 mm are placed on the lower electrode 7, which is made by winding a wire rod 6 made of CrCu with a wire diameter of 0.11 mm around a core metal 5 made of CrCu.
Ag40w/o-Pt10w/o-Au10w/o-
Electrical contact wire 2 made of Cu14w/o-Zn1w/o
22 mm wide, 1 mm long, and 0.1 mm thick.
Arrange the base material 1 made of nickel silver and measure the width from the top by 24 mm.
Resistance welding is performed using the upper electrode 8 with a length of 3 mm, a length of 3 mm, and a height of 5 mm.Then, as shown in FIG. Brush 3 was obtained. Conventional example As shown in Figure 1, width is 24 mm, length is 3 mm, and height is 5 mm.
20 wires with a diameter of 0.1 mm are placed on the lower electrode 4 made of CrCu.
Pd35w/o-Ag40w/o-Pt10w/o-
An electrical contact wire 2 made of Au10w/o-Cu14w/o-Zn1w/o is arranged, and a width of 22 mm and a length of 1
A base material 1 made of nickel silver with a thickness of 0.1 mm and a width of 24 mm, a length of 3 mm, and a height of 5 mm is resistance welded onto the base material 1, and then the tip of the electrical contact wire 2 is As in the example, a sliding brush 3 was obtained by bending it downward at a right angle to a length of 1 mm. However, when 100 each of the thus obtained sliding brushes of the example and the conventional example were inspected, it was found that
It was as shown in the table below.

[Table] Defective products include those in which the electrical contact wire 2 expands outward beyond the tolerance as shown in Figure 3a, and those in which the electrical contact wire 2 is warped vertically and varies in height as shown in Figure 3b ( The above-mentioned cases include those that appear after molding), other cases where the electrical contact wire 2 has an unwelded part and falls off, and the welded part melts and breaks from that part, etc. As is clear from the above table, in the sliding brush 3 of the embodiment, the electrical contact wire 2 spreads outward,
There is no unevenness in the top and bottom, and the base material 1
It can be seen that the weld is completely welded and nothing falls off, and there is nothing that melts or breaks from the weld. In addition, on the surface of the base material 1 to which the electrical contact wire 2 is to be joined,
By providing a protrusion perpendicular to the electrical contact wire 2 and performing projection welding, the electrical contact wire 2 can be reliably welded in a uniform and stable state even under conditions of low current and low pressure. Further, in the above embodiment, the electrode 7 made of a very thin wire 6 wound around the core metal 5 is used as the lower electrode, but it can also be used as the upper electrode and the arrangement of the base material 1 and the electrical contact wire 2 is reversed. It's good. As described above in detail, the method for manufacturing a sliding brush of the present invention uses an electrode made of a core metal and a large number of ultra-fine electrical contact wires when resistance welding a base material and a large number of ultra-fine electrical contact wires. Since resistance welding is performed by aligning the wires with equal gaps, the electrical contact wires do not fluctuate vertically and horizontally, and the electrical contact wires are reliably welded to the base material in a uniform and stable state. This has an excellent effect in that it is possible to obtain a sliding brush of good quality in which the electrical contact wire does not fall off or break from the welded part during the forming process. In addition, in the method of manufacturing a sliding brush of the present invention, an electrode is used in which an ultra-fine wire is wound around a core metal, so this electrode serves as a guide to the welding part of the electrical contact wire with the base material. Another effect is that feeding and positioning of the contact wire can be performed accurately and smoothly. Furthermore, the above-mentioned electrode has the additional advantage that the electrode surface can be easily replaced by rotating the core metal, and there is no need for polishing by simply rewinding the ultra-fine wire, making maintenance extremely easy.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal cross-sectional view showing the welding process of the electric contact wire in the conventional method of manufacturing a sliding brush, and Fig. 2 is a longitudinal cross-sectional view showing the welding state of the electric contact wire.
FIGS. 3a and 3b are a plan view and a side view showing a defective state of a sliding brush obtained by a conventional method, respectively;
FIG. 4 is a perspective view of the lower electrode used in the manufacturing method, FIG. 5 is a longitudinal cross-sectional view showing the welding process of the electric contact wire in the sliding brush manufacturing method according to the present invention, and FIG. FIG. 3 is a side view showing a process of forming an electrical contact wire in the method for manufacturing a sliding brush according to the invention. DESCRIPTION OF SYMBOLS 1... Base material, 2... Electrical contact wire, 3... Sliding brush, 4... Lower electrode used in the conventional method, 5... Core bar, 6... Extra-fine wire, 7... …
The lower electrode used in the method of the present invention, 8...
...Top electrode.

Claims (1)

[Claims] 1. A large number of ultra-fine electrical contact wires are placed in contact with an electrode made of ultra-fine wires wound around a metal core, and are focused horizontally. A base material is placed in contact with the wires, and the electrode with a flat tip end is used to create resistance. A method for manufacturing a sliding brush, which comprises welding and then forming a large number of electrical contact wires into a desired shape.