JPS62136801A - Manufacture of 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] [Field of Application of the Invention] The present invention relates to a method of manufacturing a sliding contact that slides on a resistance substrate of a variable resistor included in a liquid level sensor, a pressure sensor, etc. be.

[Month of invention]

The conventional process for manufacturing this type of sliding contact is as shown in Figures 2 (a) to (e). 20 is cut to a predetermined length, and the cut piece is processed into a header to form a stud-like contact member 21. Next, this contact member 2
1 is fixed to the tip of an elastic metal plate 22 made of a conductive plate, such as a phosphor bronze plate, by crimping, thereby creating a sliding contact. However, on the surface of the contact member 21 in a sliding contact having such a structure, the contact member 2
1. Surface treatment 23 such as gold plating is generally performed to prevent poor conductivity due to surface corrosion.
1, when the contact member 21 is crimped and fixed to the metal plate 22, the thickness of the soft and malleable gold plating layer becomes locally thin during the crimping process, so the contact member 21 is After the crimping and mounting of the contact member 21, the surface of the contact member 21 needs to be plated with gold again. In addition, since the cost of gold is high, it is required to form a gold plating layer as thin as possible in necessary parts. There was a problem in that it took a lot of time and effort to put the cent into the tank, which increased the product cost.

[Purpose of the invention]

The present invention has been made in view of such conventional problems, and it is possible to create a contact with excellent contact conductivity while reducing the amount of gold used by applying a gold plating layer only to the necessary parts of the contact member. The purpose is to provide a method for manufacturing contacts with excellent contact durability and productivity.

[Embodiments of the invention]

The present invention will be explained in detail below based on the embodiment shown in FIG.

Reference numeral 1 denotes a tubular material for forming a contact member, and this tubular material 1 is made of, for example, a silver-baladum alloy that has excellent contact conductivity and corrosion resistance. This tubular material 1 is cut into rings of a size suitable for convenient use as a contact to obtain a contact forming member 2 as shown in FIG. 1(b). Next, on the tip of an elastic metal plate 4 made of, for example, a phosphor bronze plate, which has a through hole 3 in the plate thickness direction drilled in the tip, the center hole 5 axis of the contact component 2 is aligned with the through hole 3. The contact component 2 is fixed onto the elastic metal plate 4 by spot welding means (see FIG. 1) with the central axes aligned, and then the contact component 2 is fixed onto the metal plate 4. 2, type 6
Header processing is performed to form the surface of the contact component 20 under pressure into a substantially hemispherical shape, thereby forming the contact base 7 as shown in FIG. 1E. The gold wire 8 is inserted into the center hole 5 and the through hole 3 of the contact base 7 so as not to come into contact with those holes 5°3, and a high potential is applied between the gold wire 8 and the contact base 7. As a result, a gold vapor deposited layer 9 is formed on the inner circumferential surface of the central hole 5 and the through hole 3 by melt vapor deposition of the gold wire 8.
The desired contact point is completed.

In this way, according to the method of manufacturing a contact according to this embodiment, the contact base 7 is formed on the contact component member 2 which is made of a tubular material and has a substantially hemispherical shape and has a through hole 3 in the center. Since the gold vapor deposited layer 9 is formed on the inner peripheral surface of the through hole 3, the top surface of the contact component 2, that is, the contact surface with the resistor pattern, etc., is annular, so that it is different from the conventional point contact contact structure. Since the contact surface can be secured wider than the conventional one, it has the advantage of improving contact performance. Furthermore, since the annular contact surface is a gold vapor deposited layer,
The electrical conductivity (contactability) K is excellent, and even if the top surface of the contact base 7 wears due to sliding, the edge of the gold vapor deposited layer 9 on the inner peripheral wall surface of the through hole 3 appears on the contact surface. Since the contact surface is always formed of a gold vapor-deposited layer, it has the effect of providing excellent contact reliability. Furthermore, since the gold vapor deposition layer 9 is applied only to the inner circumferential surfaces of the through holes 3 and 5, the amount of total material used can be reduced, and costs can be reduced. In addition, since the contact base 7 has through holes formed by the through holes 3 and 5, this through hole has the effect of effectively dissipating heat generated by sliding friction heat, electric current heating, etc. of the contact base 7. be.

[Summary of the invention]

As described above, in the present invention, a short tube 1 made of a metal alloy with excellent corrosion resistance such as silver-silver is placed between the through hole 3 and the center of the short tube 1 in a metal plate 4 having a through hole 3. After welding, the short pipe 1 is processed into a header to form the contact base 7, and then the center hole 5 of the contact space 7 is welded in communication with the hole 5.
This is a method of manufacturing a contact point characterized in that a gold thin film layer 9 is provided at 3.degree.

〔Effect of the invention〕

Therefore, according to the contact structure produced by this contact manufacturing method, since the contact surface of the contact base 7 is in the shape of a square,
The contact surface is wider than that of conventional point contact structures, and the annular contact surface has a gold vapor deposited layer exposed, so it has excellent electrical conductivity (contactability). Even if the top surface of the contact base 7 wears due to sliding, the edge of the gold vapor deposited layer 9 on the inner circumferential wall of the through hole 3 appears on the contact surface, and a contact surface of the gold vapor deposited layer is always formed. This has the effect of providing excellent contact reliability. Furthermore, since the gold vapor deposited layer 9 is applied only to the inner circumferential surfaces of the through holes 3 and 5, the amount of total material used can be reduced, and costs can be reduced. In addition, since the contact pad 7 has through holes formed by the through holes 3 and 5, the sliding friction heat of the contact pad 7, heat generated by flow heating, etc. can be effectively dissipated through the through holes. I can feel the effect.

[Brief explanation of drawings]

Figures 1 (a) to (f) are explanatory diagrams showing the manufacturing process of a contact according to the present invention, and Figures 2 (a) to (f) are explanatory diagrams showing the manufacturing process of a conventional contact. . 1... Tubular material 2... Contact component 3...
・Through hole 4...Metal plate 5...Center hole
6... Mold 7... Contact paste 8... Gold wire 9... Gold vapor deposited layer. Figure 1

Claims (1)

[Claims] A short tube (1) made of a metal alloy with excellent corrosion resistance such as silver-palladium is attached to a metal plate (4) having a through hole (3) and the through hole (3) and the center hole of the short tube (1). (5), and after welding, header processing is performed on the short tube (1) to form a contact base (7), and then the contact base (7) is welded.
) A method for manufacturing a contact point, characterized in that a gold thin film layer (9) is provided in the central hole (5), (3) of the contact point.