JPS61190819A - Manufacture of electric contact - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to an improvement in a method for manufacturing an electric contact in which an electric contact is formed by stamping a clad wire piece obtained by cutting a clad wire.

(Prior Art) Conventionally, as shown in Fig. 1, a metal 1 for electrical contact made of a special metal such as gold or silver is pasted on one or both longitudinal sides of a strip-shaped conductive base metal material 2 such as copper. A clad wire piece a is cut from the end of the so-called clad wire A so as not to produce chips, and then a columnar preformed material 6a is formed using a die 3 and a punch 4.5 as shown in FIG. 2. Description of the Related Art A method of manufacturing an electric contact is known in which a contact portion made of an electric contact metal 1 is integrally formed by stamping.

This conventional method is advantageous in that it does not produce any special precious metal chips used as the contact material, and the process is simplified because the contact material is pasted in advance.

(Problems to be Solved by the Invention) In this conventional method, a square clad wire piece a is pressed or forged into a preformed material 6a in the shape of a cylinder, hexagon, octagon, etc. using a punch and die. During molding, as shown in FIG. 3(a), the square part of the square columnar clad wire piece a moves in a direction perpendicular to the direction of pressure applied by the punch 4.5, that is, toward the end face side of the clad wire piece a. It protrudes in a wavy manner. After that, the end surface comes into contact with the dies 3, 3, and as shown in FIG.
As shown in b), a cylindrical preliminary IR8 material 6 with flat end faces is formed.

Therefore, in the preformed material 6, the boundary C between the contact metal material 1 and the conductive base metal material 2 has a wavy shape, and the contact metal material 1 is further arranged at the contact part as shown in FIG. If a rivet-like contact 6b is formed, the wavy pattern of the boundary C- becomes even larger, and only the wavy pattern part does not function as the desired electrical contact. Therefore, in order to obtain a sufficient function, the boundary C1C 1, a large amount of expensive contact metal material 1 must be used, and the electrical contacts formed must therefore be expensive.

In view of this point, the present invention provides a method for forming an electrical contact in a desired shape by stamping a clad wire piece obtained by cutting a clad wire material, such as by pressing or forging, by combining the contact metal material and the base metal material. The purpose of this product is to provide a processing method that allows the boundary line to have extremely small corrugations compared to conventional products, to minimize the use of expensive metal materials for contacts, and thereby to reduce prices.

<Means for solving the illumination point a> The gist of the present invention for solving the above-mentioned conventional problems and achieving the intended purpose is to use a base metal material made of a strip-shaped conductive material. A clad wire with a metal layer for electrical contact adhered to one longitudinal surface or both surfaces at mutually symmetrical positions is cut in a direction perpendicular to the longitudinal direction to obtain a square prism-shaped clad wire having the metal layer for electrical contact on the end surface. In the method of manufacturing an electric contact, the clad wire piece is formed into a desired electric contact shape by pressing or forging, and the clad wire piece is formed so that the length between its two end faces does not become long. With the distance between the end faces regulated, the surrounding surfaces excluding both end faces are pressurized with a movable punch to make the entire preformed material into a cylindrical shape or a prismatic shape closer to a cylindrical shape than the original square prism, and the imitation press or The method of manufacturing an electric contact is characterized in that the electric contact is formed by forging into an electric contact having a contact portion having a circular cross section substantially concentric with the axis of the preformed material.

The electrical contact metals used include precious metals such as gold and silver, precious metal alloys, noble metal-containing alloys, and other oxidized metals, and the conductive base metals include iron, copper, nickel, and their alloys or Alloys containing them are typical, and sometimes silver, palladium, etc. are also used.

Furthermore, the clad wire material may be made by using a cheaper metal as the base metal material than the metal material for the contact, and may be the outer plating of these tension materials, and the joining method may be brazing, welding, or pressure welding. The shape of the clad wire piece may be one cut so that the interface between the metal material for the electrical contact and the base metal material does not form a wave (although the shape may vary). It is something that can be formed.

(Function) The manufacturing method of this electric contact is to insert a rectangular prism-shaped clad wire piece into an immovable punch that regulates the periphery except for both end faces, and pressurize both end faces to create a cross-sectional shape that is or is similar to that of the immovable punch. When deforming into a shape, the space between both end faces is compressed and the whole is deformed in the direction of becoming thicker, and the square columnar corner is first restricted from moving in the thickness direction by the inner surface of the immovable punch.
Because the material is compressed from both end faces, it is prevented from moving toward the end faces, and it moves in the circumferential direction and is deformed into a cylindrical shape or a state close to this, and the boundary between the base metal material and the electrical contact metal is The ripples will be reduced.

(Example) Next, an example of implementing the present invention will be described with reference to the drawings from FIG. 5 onwards.

In the figure, reference numeral 10 denotes a clad wire piece obtained by cutting a clad wire in the same manner as described above, and this clad wire piece 10 is made by pasting an electrical contact metal material 12 made of silver on the upper surface of a base metal material 11 made of a nickel strip. ing. As shown in FIG. 6, this clad wire piece 10 is inserted into upper and lower movable punches 13.
13 is compressed from the upper and lower end surfaces to form a cylindrical electrical contact preform material 15 that matches the shape of the surrounding stationary bunch 14, and this material 15 is further compressed from the end surface of the electrical contact metal material 1211. By pressing, an electric contact 16 having a contact portion 16a having a circular cross section as shown in FIG. 8 is formed.

In addition to the above-mentioned cylindrical shape, the shape of the preformed material 15 may be formed into a shape close to a cylindrical shape such as a helical shape.
The electrical contact may be pressed into the shape shown in the figure, or the final product electrical contact may be in the form of a rivet as shown in FIG. 9. Furthermore, as shown in FIG.゜12, and electrical contact parts 1 are placed on both ends of the contact.
It is also possible to form a 68° 16a and sandwich the conductive piece 17 in between.

In this way, when the periphery of the clad wire piece 10 is regulated within the stationary bunch 14 and both end faces are pressurized with the movable punch 13.13, the square prism-shaped corners bulge in the radial direction inside the stationary bunch 14. As a result, the metal at the corner moves in the circumferential direction and is formed into a cylindrical shape or a prismatic shape close to this, and the boundary between the base metal material 11 and the electrical contact metal material 12 is therefore greatly undulated. Therefore, a flat preformed material 15 is obtained. Then, by pressing this into an electric contact 16 having a contact portion 16a with a circular cross section concentric with the axis thereof, the boundary between the two metal materials is formed with almost no blurring.

(Effects of the Invention) The method for manufacturing an electric contact of the present invention is configured as described above,
Each metal is formed by pressing a rectangular column-shaped clad wire piece made of multiple metal materials stacked on top of each other into a cylinder or similar prismatic shape by pressing both end faces in an immovable punch that controls the curve W4. A preformed material is obtained in which the boundaries of the material are maintained in a substantially flat state, and by pressing this into a contact, it is possible to have almost no boundaries.

[Brief explanation of drawings]

Figure 1 is a perspective view of the clad wire rod and clad wire piece, Figure 2 is a perspective view of the clad wire rod and clad wire piece.
The figure is a cross-sectional view of the conventional processing method, Figure 3 (a) (0) is a perspective view showing the processing steps of a preformed material in the same process, and Figure 4 is a perspective view of a contact formed by the same process. Figure, 5th
The figure is a perspective view of a clad wire piece used in an embodiment of the present invention.
Fig. 6 is a sectional view showing the same processing method, Fig. 7 is a perspective view of the preformed material, Fig. 8 is a front view of the completed contact, Fig. 9 is a front view of an example of a contact preform, and Fig. 10 The figure is a sectional view of still another example of the contactor. A... Clad wire rod, 10... Clad wire piece, 11... Base metal material, 13...
...Movable punch, 14...Imovable punch, 15
...Preformed material, 16...Electric contact, 16a...Contact part. Figure 1 O' Figure 5 Figure 6 Figure 8 Figure 10 Figure 7 Figure 9

Claims (1)

[Claims] A clad wire with a metal layer for electrical contact pasted on one longitudinal side of a base metal material made of a strip-shaped conductive material or on both sides at mutually symmetrical positions is cut in a direction perpendicular to the longitudinal direction, and the end face is coated with the electrical contact layer. A method for manufacturing an electrical contact in which a rectangular prism-shaped clad wire piece having a contact metal layer is formed, and the clad wire piece is formed into a desired electrical contact shape by pressing or forging. Insert it into an immovable punch that regulates the circumference except for both end faces,
Both end faces of the clad wire piece are pressed with a movable punch to make the entire preformed material into a cylindrical shape or a prismatic shape closer to a cylindrical shape than the original square prism, and then press or forged to form the preformed material. 1. A method of manufacturing an electrical contact, comprising forming an electrical contact having a contact portion having a circular cross section substantially concentric with the axis of the electrical contact.