JPH0154810B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Application) The present invention relates to a method of manufacturing a contact using a noble metal material such as platinum, gold, or silver as a contact material.

(Problems with the Prior Art) Conventionally, this type of contact has been made entirely of a noble metal material such as silver. However, due to the rising price of precious metal materials, there is an increasing demand for reducing the amount of precious metals used, so the head part is made of copper.
Some have a layer of silver material pasted on the surface.

By the way, the center of the contact generally serves as the point of contact, and the center is prone to wear. Therefore, if the silver material layer is made too thin, the internal copper head will be exposed immediately, and if the silver material layer is made thick, the portions of the silver material layer other than the contact points will simply be ineffective for heat transfer and heat diffusion. Although there is, it is wasted in terms of contact performance.

In addition, there is also a device in which a noble metal chip having a diameter slightly smaller than the shaft is fixed to the flat end of the shaft of the copper head, and the head is fixed to the contact plate by pressing and deforming the peripheral edge of the chip. In this case, the fixed surface may be deformed when deformed under pressure, and in such a case, there is a risk of chip separation.

(Purpose) The present invention has been made in view of the above points, and its purpose is to sufficiently compensate for the thickness of the precious metal layer in the contact area while reducing the required absolute amount of the precious metal material, and to provide a copper head. To provide a method for manufacturing a contact in which chip peeling is less likely to occur by extremely reducing the stress applied to the joint surface between a noble metal chip and a copper head when fixing the contact plate by pressure deformation (crimping) to a contact plate.

(Example) Hereinafter, an example of the present invention will be described based on FIGS. 1 to 5.

1 is a contact plate, made of copper or phosphor bronze plate material,
It is formed in the shape of a small hole 2.

3 is a rivet-shaped head made of a base metal material such as copper, and has a medium-diameter shaft portion 4 that is inserted into the small hole 2.
It is formed in a shape having a stepped portion 6 having a smaller diameter than the shaft portion 4, and a large diameter flange portion 5 located on the opposite side of the stepped portion 6 and sitting on the upper surface of the contact plate 1. 4a is the lower surface of the boundary between the shaft portion 4 and the step portion 6.

Reference numeral 7 denotes a contact chip piece made of a noble metal, which is formed into a disk shape having approximately the same diameter as the stepped portion 6 or a slightly smaller diameter from a noble metal material such as platinum, gold, silver, or a silver alloy.

First, the contact plate 1 is manufactured, and then or simultaneously the rivet-shaped head 3 is manufactured, and then, as shown in FIG. 2, the contact chip piece 7 is fixed to the lower end surface of the stepped portion 6 of the head 3. If both axial surfaces of the contact are used as contact surfaces, the contact chip 7 is also fixed to the upper end surface of the flange 5 as shown in the drawings of the embodiment.

Next, insert the shaft portion 4 of the head 3 into the small hole 2 of the contact plate 1.
As shown in Fig. 3,
(or lower mold Y) as shown in Fig. 4.
Close both molds X and Y. Both molds X and Y have a concave curved surface at a portion corresponding to the contact tip piece 7, and a portion corresponding to the lower boundary surface 4a of the lower mold Y pressurizes and deforms the lower boundary surface 4a to It is shaped so that it protrudes outside the outer periphery of the portion 4. Therefore, the contact plate 1 is held between the flange portion 5 and the sideward protruding portion 4b of the lower boundary surface 4a due to this pressurization. This pressurized deformation of the lower boundary surface 4a is
Since this is done without using the contact chip 7, almost no mechanical stress is applied to the bonding surface 4c of the contact chip 7 against the end surface of the stepped portion 6.

Figure 5 shows the completed contact removed from both molds X and Y.

(Effects) The contact manufacturing method of the present invention includes manufacturing a contact plate 1 having a small hole 2, a shaft portion 4 inserted into the small hole 2, a stepped portion 6 having a smaller diameter than this shaft portion 4, and a contact plate 1 having a diameter smaller than that of the shaft portion 4. 1
A rivet-like head 3 made of copper is manufactured with a flange 5 sitting on the upper surface, and a plate-shaped noble metal such as platinum, gold, silver, etc., with a smaller diameter or the same diameter as the outer diameter of the step 6 is attached to the lower surface of the step 6. The manufactured contact chip piece 7 is fixed, the shaft part 4 of the head 3 is inserted into the small hole 2 of the contact plate 1, and the lower surface 4a of the boundary between the shaft part 4 and the step part 6 is pressurized with the lower mold Y. Since the contact plate 1 is sandwiched between the lateral protrusion 4b of the lower boundary surface 4a due to this pressure and the flange 5, the heat dissipation and capacity of the contact are not impaired by the head 3, and the electrical Since the contact is made with the chip piece 7 of the minimum necessary width, the thickness of the precious metal material can be increased by using the same amount as that covering the entire surface of the head, or by reducing the thickness to the minimum necessary width. It is possible to significantly reduce the amount of material used, and therefore, while reducing the absolute amount of precious metal material required, it can sufficiently compensate for the thickness of the precious metal layer in the contact area.Furthermore, when pressurizing and deforming and fixing the copper head to the contact plate, the precious metal chip and the copper Since the stress applied to the joint surface with the head is extremely reduced, chip peeling is less likely to occur.

[Brief explanation of drawings]

Fig. 1 is an exploded perspective view showing the constituent members of an embodiment of the present invention, Fig. 2 is a front view of the chip fixed to the head, Fig. 3 is a longitudinal sectional view immediately before deformation under pressure,
Figure 4 is a longitudinal cross-sectional view immediately after deformation under pressure, and Figure 5 is
FIG. 3 is a front view of a completed contact. 1...Contact plate, 2...Small hole, 3...Head, 4
...Shaft part, 4a...Boundary lower surface, 5...Brim part, 6...
...Stepped portion, 7...Precious metal chip.

Claims (1)

[Claims] 1. Fabricate a contact plate with a small hole, and fabricate a copper rivet-shaped head with a shaft part to be inserted into the small hole, a step part with a smaller diameter than this shaft part, and a collar part that sits on the top surface of the contact plate. , A contact chip piece made of a flat precious metal such as platinum, gold, silver, etc., with a diameter smaller than or the same diameter as the outer diameter of the stepped portion is fixed to the lower surface of this stepped portion, and the shaft portion of the head is inserted into the small hole of the contact plate. Then, pressure is applied to the lower surface of the boundary between the shaft portion and the stepped portion using the lower mold, and the contact plate is held between the lateral protrusion of the lower surface of the boundary due to this pressure and the flange. Features: Contact manufacturing method.