JPH0245292B2 - FUKUGODENKISETSUTENZAINOSEIZOHOHO - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a composite electrical contact material, which is used as a contact point for electronic components such as a switch, and has a noble metal such as silver bonded to the contact portion.

Generally, electronic components are used by laminating precious metal materials such as gold or silver on the contact parts, and the manufacturing of such composite contacts has traditionally involved cutting wires made of ordinary highly conductive metal materials and precious metal materials, respectively. This method uses a laminated material in which precious metal material and ordinary conductive metal material are laminated together in advance, and then punches or cuts the material. A common method is to prepare the material as a raw material and further form it into the desired shape by cold-pressing.

In manufacturing such composite contact materials, if the hardness of the precious metal material and the normal contact material to which it is bonded is significantly different, for example, the materials to be bonded to each other may be silver versus nickel, silver cadmium oxide alloy versus copper-nickel alloy, In cases such as silver-copper alloy vs. iron, or silver-nickel alloy vs. bronze, etc., when forming using a wire rod, the soft precious metal material deforms more than the hard metal material, and this causes cold forming. In addition to incomplete crimping, it was also difficult to form a uniform layer of precious metal material on the contact portion as an electrical contact, which necessitated the use of a laminated material that had been bonded in advance.

However, when using laminated materials, the method of punching them into a circular shape has a poor yield of the product compared to the raw materials and ends up being expensive, while the method of using narrow laminated materials and cutting them makes the material Because of the rectangular shape, the compression molding process was complicated, and there were problems such as difficulty in obtaining a noble metal material layer of uniform thickness on the contact area of the product.

In view of the above-mentioned problems, the present invention manufactures a composite electrical contact material that can obtain good molding by cutting wire rods, butting them together and applying pressure when manufacturing composite contacts using materials with significantly different hardnesses. It is intended to provide a method;
The gist of this is that hard metal wires such as iron, nickel, and copper-nickel alloys and soft metal wires such as silver, silver-copper alloys, and silver-nickel are cut into appropriate lengths.
A state in which the cut surfaces are butted against each other, compressed in the direction of the butt, and temporarily attached, and the temporarily attached soft metal wire portion of the composite material is housed in a cylindrical mold to partially suppress deformation. The mainly hard metal wire protruding from the receiving mold is pressed and deformed using a rough forming mold, and then the soft metal wire is deformed while extruding from the receiving mold into the rough forming mold to form a rough processed product. , a method for manufacturing a composite electrical contact material, characterized in that the rough processed product is heat treated and then pressurized in a finishing press mold.

Next, an example of implementation of the present invention will be described with reference to the drawings.

1 in the figure is a receiving mold. This receiving mold 1 is housed in a guide cylinder 3 fixed to a base 2 so as to be able to move up and down, and is biased upward by a spring 4. Mold 1
A hollow material receiving hole 5 having a cylindrical shape vertically extends through the center of the material receiving hole 5, and an extrusion pin 6 is inserted into the material receiving hole 5 from the bottom surface of the receiving mold 1. The extrusion pin 6 has its base 6a positioned with respect to the base 2, and is moved up and down relative to the inside of the material storage hole 5 when the receiving mold 1 is moved up and down. That's what I do.

On both sides of the receiving mold 1, a soft metal wire extrusion tube 7 for supplying a wire made of a precious metal material and a hard metal wire extrusion tube 8 made of a normal contact wire are provided. A wire rod a and a hard metal wire b are extruded, and the extruded wire rods a and b are passed through cutters 9 and 1, respectively.
0, held by a gripping mechanism (not shown), and moved onto the material receiving hole 5 of the receiving mold 1,
The soft metal wires a are placed separately into the material storage hole 5 with the soft metal wires a facing down.

The wire rods a and b accommodated in the material storage hole 5 in this manner are pressurized from above and below within the material storage hole 5, as shown in FIG. 2, to temporarily attach both wire rods a and b. This temporary attachment is performed by the first punch 11 inserted downward from the upper end opening in the material storage hole 5 and pressurized between it and the extrusion pin 6.

After this temporary attachment, move back the first punch 11,
A rough forming mold 12 is lowered from above the receiving mold 1. This rough forming mold 12 has a concave part 12a in the center of the lower surface, which has a shape similar to that of a finished product, and a cylindrical spacer metal fitting 13 is slidably fitted to the outer periphery of the concave part 12a, and its tip is placed under the rough forming mold 12. It is urged in the protruding direction by a spring 14 in a state in which it protrudes further downward from the end face. This spring 14 is stronger than the spring 4 for the receiving mold 1 described above, and when the rough forming mold 12 is lowered, the spacer fitting 13 first comes into contact with the upper surface of the receiving mold 1, and the rough forming mold The lower surface of the mold 12 and the upper surface of the mold 1 are kept at a constant distance and are lowered by the stroke of the mold 1. Further, the interval formed by the spacer metal fittings 13 is such that, as shown in FIG. It is considered a matter of degree of contact.

Then, by lowering the rough forming die 12, the soft metal wire a portion of the raw material to which both wire rods a and b are temporarily attached is accommodated in the material accommodation hole 5 of the receiving mold 1, and the inner surface of the concave portion 12a is Pressing is started on the hard metal wire b, and when the rough forming die 12 is further lowered, the receiving die 1 is lowered while maintaining the spacing provided by the spacer fittings 13, which allows the material to be relatively Rough forming mold 1 while being extruded from receiving mold 1
Processing proceeds according to step 2.

In this way, the hard metal wire b is processed first, and when the soft metal wire a is pushed out almost completely from the material receiving hole 5 as shown in FIG. It touches and the descent stops. In this state, the rough forming mold 12 is further lowered, the spacer fitting 13 is pushed up relatively, and the distance between the rough forming mold 12 and the receiving mold 1 is reduced, and the entire material is rough formed in the state shown in FIG. is completed. Next, this roughly formed product is subjected to heat treatment to integrate both materials.

In this way, in the roughly formed product, the hard part b' made by crushing the hard metal wire b is rounded by the die surface of the rough forming die 12, and the soft part a' made by crushing the soft metal wire is formed into a round shape. A pressure mark 15 from the tip of the extrusion pin 6 remains in the center.

Next, as shown in FIG. 6, use another receiving die 17 and a pressing die 18 to place the rough-processed product between the two dies 17 and 18, with the hard part b' of the rough-processed product facing the receiving die 17 side. Pressure is applied to form a finished product 19. This finished product 19
is a hard part having a soft part a' with a rounded periphery at the top and a welding protrusion 20 protruding from the bottom.
b′ is placed. This finished product 19 is further heat treated to integrate the soft portion a' and the hard portion b'.

The method for manufacturing a composite electrical contact material of the present invention is configured as described above, in which a soft metal wire made of a noble metal material is housed in a material receiving hole of a receiving mold, and the hard part is first processed using a rough forming mold. Then, by gradually extruding the soft metal wire from inside the mold and compression molding, the hard part is processed first while the deformation of the soft part is suppressed, and therefore both parts are processed. It is possible to make the deformation of both parts to the same degree in the joint part of This process allows the soft precious metal layer to be made uniform.

Furthermore, by performing finishing press after heat treatment after forming the rough processed product, there are no push-up pin marks on the bottom of the final product, and it is possible to produce a wide variety of shapes that require welding protrusions. It is easy to do.

[Brief explanation of the drawing]

The drawings show an example of the implementation of the method of the present invention, and FIG. 1 is a sectional view showing the state before cutting the wire, FIG. 2 is a sectional view showing the temporary attachment state, and FIG. 3 is the start of forming with a rough forming die. Figure 4 is a cross-sectional view showing the state when the mold has stopped descending, Figure 5 is a cross-sectional view showing the state after the rough forming process is completed, and Figure 6 is a cross-sectional view of the finishing process. It is. a...Soft metal wire, b...Hard metal wire, 1
...Receiving mold, 2...Base, 3...Guide tube, 4...
Spring, 5...Material accommodation hole, 6...Extrusion pin, 7...Soft metal wire extrusion tube, 8...Hard metal wire extrusion tube, 11...Ichiban punch, 12...Rough forming mold, 13... Spacer metal fittings, 14...spring.

Claims (1)

[Claims] 1. Cut a hard metal wire such as iron, nickel, copper-nickel alloy, etc. and a soft metal wire such as silver, silver-copper alloy, silver-nickel, etc. into appropriate lengths, butt the cut surfaces against each other, and compress in the direction of the butt. Both are temporarily attached, and the soft metal wire portion of the temporarily attached composite material is housed in a cylindrical receiving mold, and while deformation is partially suppressed, the mainly hard metal wire portion protruding from the receiving mold is roughly formed. Pressure is applied with a mold to deform the soft metal wire, and then the soft metal wire is deformed while being extruded from the receiving mold into a rough forming mold to form a roughly processed product;
A method for producing a composite electrical contact material, which comprises heat-treating the rough-processed product and then pressurizing it in a finishing press mold.