JP3070806B2 - Electrical contact material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an intermittent electric contact of a current circuit such as a relay and a switch.

[0002]

2. Description of the Related Art Conventional electrical contacts generally use different electrical contact materials in combination on the anode side and the cathode side in terms of polarity. For example, Pd on the anode side
-Ru alloy first layer and base material Cu for contact spring welding-
A double-layered contact of a second layer of Ni alloy is used, while the cathode side facing this contact has a first layer of pure Au or Au alloy and a second layer of Ag alloy such as Ag-Ni alloy or Ag-Pd alloy.
A combination of different electrical contact materials composed of a three-layer tensioned contact of a layer and a third layer of a Cu-Ni alloy base material for contact spring welding has been used. However, in this conventional method of use, in recent multifunctionalization, there is a restriction due to the polarity, so that a three-layered Au or Au alloy contact is provided on the opposite anode side, and a two-layered Pd-Ru alloy is provided on the cathode side. When the contact and the electric circuit are connected, the transfer occurs from the anode side to the cathode side, so that a hole is formed on the anode side and a projection is formed on the cathode side, so that there has been a problem that poor separation occurs.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an electric circuit having a degree of freedom of polarity in an electric circuit without restriction on designation of an anode side and a cathode side of a relay, a switch and the like. Provide contact materials.

[0004]

The electric contact material according to the present invention for solving the above-mentioned problems comprises Au or Au on at least the contact surface of a two-layer tension contact of a first layer of a Pd-Ru alloy and a second layer of a Cu-Ni alloy.
It is characterized by being plated with an alloy.
Another invention is characterized in that the thickness of the plating of Au or Au alloy of the above-mentioned electrical contact material is 0.5 to 6 μm.

[0005]

Since the electrical contact material of the present invention having the above-mentioned structure is plated with Au or an Au alloy at least on the contact surface, the contact reliability in the initial stage and on the dry circuit is ensured. Therefore, in the arc generating region,
Transfer occurs, but Pd of the first layer having a high melting point and a high hardness
The wear is suppressed by the Ru alloy and occurs only flat. Therefore, poor separation does not occur. Further, since the same electrical contact material is used as the same type of opposing material on the anode side and the cathode side, the degree of freedom of the polarity is secured.
In the case of a clad material of Au or an Au alloy instead of plating, blisters and the like are easily generated due to a difference in hardness between Au or the Au alloy and the Pd-Ru alloy, and there is a concern that the influence on the bonding strength may be caused. However, there is a difficulty in thinning, and there is also a method of interposing an Ag alloy such as an AgPd alloy for stabilizing the bonding strength. From the point that welding occurs before contact with the Ru alloy
The plating of u or Au alloy is extremely effective. Further, Au or Au alloy plating is effective if it is at least on the contact surface, and is even more effective if plating is applied including the surroundings so that corrosion resistance is improved. Further, Au or Au
The thickness of the alloy plating is preferably 0.5 to 6 μm,
If it is less than m, the number of pinholes in the plating is large and the contact reliability is lacking. If it exceeds 6 μm, the plating process takes a long time and the cost is increased due to expensive Au or Au alloy.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention and conventional examples will be described below. First, as an example, a round wire of material Pd-Ru10wt% is rolled to produce a tape having a width of 0.7mm and a thickness of 0.8mm, and a tape of material Cu-Ni 30wt%, a width of 0.7mm and a thickness of 0.7mm is laminated and formed. 0.7mm upper bottom, 0.8m lower bottom by processing
m, a tape of Pd-Ru having a thickness of 0.75 mm and a total thickness of 1.4 mm. Next, Au—Co 0.1 wt% plating is applied on the entire surface for 2-3 times.
The electrical contact material of the embodiment was subjected to μm application. On the other hand, as a conventional example, Pd-Ru 10 wt% / Cu-Ni 30 wt having the same dimensions as the embodiment except that plating of Au-Co 0.1 wt% was not performed.
% Two-layered contact and Au-Ag 10 wt% /
Ag-Ni10wt% / CuNi30wt% and thickness 0.01mm /
It was a three-layer tensioned contact having a thickness of 0.75 mm / 0.64 mm and a total thickness of 1.4 mm. However, with a DC circuit of current 150mA and voltage 96V, switching frequency 10HZ,
A contact test was carried out under a load R load and a contact force of 8 to 10 grf, and the number of operations and defective characteristics were examined. The following results were obtained.

[0007]

[Table 1]

[0008]

As described above, according to the electrical contact material of the present invention, the first layer of the Pd-Ru alloy and the second layer of the Cu-Ni alloy are used.
Since at least the contact surface of the two-layered contact of the layers is plated with Au or an Au alloy, there is no restriction on the designation of the anode side and the cathode side, the degree of freedom of the polarity in the electric circuit is obtained, and it is easy to use. In addition to good production efficiency and assembly efficiency, the present invention has an excellent effect of obtaining a stable and reliable long-life electrical contact that does not become detachable.

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H01H 1/04 H01H 50/54

Claims (2)

(57) [Claims] 1. An electrical contact material characterized in that at least a contact surface of a double-layered contact of a first layer of a Pd-Ru alloy and a second layer of a Cu-Ni alloy is plated with Au or an Au alloy. . 2. The plating thickness of Au or Au alloy is 0.5
2. The electrical contact material according to claim 1, wherein the thickness is from 6 to 6 [mu] m.