JPH062521U - Wire for electrical contacts - Google Patents

Abstract

(57) [Abstract] [Purpose] An object of the present invention is to provide a wire rod for an electric contact capable of ensuring good electrical continuity between the electric contact and the base metal which is caulked in the through hole of the base metal for caulking the contact. And A thin silver layer is provided on the outer periphery of a linear silver-metal oxide alloy forming an electric contact so that the electric contact is caulked with a base metal through silver.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention is an electrical contact material of silver-metal oxide alloy for various electric devices, in particular, a wire which is crimped to a base material such as a spring or base metal of a copper alloy such as beryllium copper, phosphor bronze, or brass. -Shaped electrical contact material.

[0002]

[Prior art]

 It is known that a wire rod that becomes a silver-metal oxide alloy is cut into a desired length, the cut short wire rod is inserted into a through hole of a base metal of the type described above, and caulked to form a contact. ing.

For example, in Japanese Examined Patent Publication No. Sho 63-34565, a cut piece obtained by a specific method is inserted into a contact mounting hole of a base material, and this cut piece is caulked around the contact mounting hole. , Single-headed or double-headed contact is described.

There are two points to be particularly noted for such contacts. The first point is whether or not the upper end surface or the lower end surface, which is the contact surface of the cut wire, has good contact characteristics, for example, welding resistance. Japanese Patent Publication No. 63-7648 discloses a contact material in which an oxide layer and a pure silver layer are concentrically alternately distributed on the contact surface. However, the material disclosed in this publication has a large amount of pure silver layer exposed on the contact surface, and thus there is a doubt in the welding resistance. Moreover, unlike the present invention, the contact material does not have a silver layer on the outer peripheral surface, and the contact surface, which is a feature of the present invention, is a heat-resistant silver-metal oxide alloy.

The second point is that when the cut short wire rod is crimped into the hole of the base metal, the joint surface between the wire rod and the base metal has good conductivity, and therefore the electric resistance is small. Whether or not the temperature rise is low. Japanese Patent Application Laid-Open No. 53-99463 discloses a method for producing an electrical contact strip for the purpose of favorably joining the contact material to the base material. The technique described in this publication uses a composite wire having a silver outer periphery, but the resulting contact is for brazing, and unlike the contact material for caulking according to the present invention, Further, the contact material is obtained through a complicated process such as vertically dividing the composite wire, and the present invention is fundamentally different.

[0006]

[Problems to be solved by the device]

 The present invention is intended to satisfy the above first and second points, and particularly the second point. That is, when a wire is cut into a desired length, inserted into the through hole of the base metal, and caulked to the base metal to make a contact, the caulking is different from the brazing method, etc. Since it is a method that relies on the above, there is a gap between the wire rod crimped to the base metal and the base metal. Even if this gap is small, it impedes the overall electrical conductivity of the contact structure composed of the wire and the base metal, and thus causes a rise in the relief temperature of the contact portion of the contact structure.

[0007]

[Means for Solving the Problems]

 Therefore, in the present invention, it is close to pure silver or pure silver having a high conductivity between a base metal such as a copper alloy and a contact which is caulked on the base metal and becomes a short wire material of a silver-metal oxide alloy. The silver alloy is used for caulking. ・ The silver-metal oxide alloy wire is pre-silver plated on the outer peripheral surface of the wire, and the caulking joint between the short wire of the contact wire and the base metal is performed. The silver can be easily interposed in the part.

[0008]

【Example】

 A piece of phosphor bronze plate having a width of 10 mm, a length of 63 mm and a thickness of 0.2 mm was used as the base metal 3. The base metal 3 was provided with a through hole 4 having a diameter of 0.5 mm. The short wire 1 having a diameter of 0.5 mm was passed through the through hole 4. This short wire 1 is obtained by cutting the wire shown in FIG. 1. A wire alloy of Ag-Sn8% -In4% -Ni0.1% is subjected to 1 μm silver plating 2 on the outer peripheral surface thereof, which is internally oxidized. It was done.

This silver-metal oxide alloy short wire 1 having a thin layer 2 of silver on the outer peripheral surface is passed through a through hole 4 of a base metal 3 and embedded by caulking as shown in FIGS. 2A and 2B, or as shown in FIGS. As shown in FIG. 4B, one side is caulked, or as in FIGS. 4A and 4B, both sides are caulked. The contact head diameter was set to 0.6 to 6.0 mm depending on the load capacity.

[0010]

[Effect of device]

 As a result, the electrical conductivity of the caulked portion was 106% in IACS, the temperature rise was suppressed to 40 to 50 ° C., and the same silver-metal oxide alloy wire rod (having an electrical conductivity of no silver layer on the outer peripheral surface) was used. It was remarkably superior to the temperature rise (61 to 65 ° C.) in the case of IACS of about 50 to 80%). Further, the withstand voltage could be kept at 500 V or higher and the insulation deterioration could be kept at 500 mΩ or higher, and very stable electric contact performance was obtained.

[Brief description of drawings]

FIG. 1 is an explanatory perspective view showing a wire for electrical contacts according to the present invention.

2A and 2B are contacts in which a wire according to the present invention is embedded and caulked in a base metal, in which A is a plan view and B is a cut side view.

FIG. 3 is similar to FIG. 2, showing the case of single-sided caulking,
A is a plan view and B is a cut side view.

FIG. 4 is similar to FIG. 2, showing the case of double-sided crimping,
A is a cut side view and B is a plan view.

[Explanation of symbols]

 1-Silver-Wire wire for electrical contact of metal oxide alloy 2-Silver plating layer on the outer periphery of wire 3-Base metal such as copper alloy 4-Thread hole

Claims (2)

[Scope of utility model registration request] 1. A wire rod for an electrical contact comprising a linear silver-metal oxide alloy and a thin layer of silver or a silver alloy provided on the outer peripheral surface of the linear alloy, the wire rod having an axis thereof. When cut in a direction that crosses, the cut end surface forms a contact surface,
A wire rod for electrical contact, wherein the above-mentioned thin layer of silver or silver alloy serves as a caulking joint surface with the base metal when caulked in the hole of the base metal. 2. A wire rod for electrical contacts crimped in a hole of a base metal of copper or copper alloy, the wire rod being a linear silver-metal oxide and pure silver or silver close to pure silver on the outer peripheral surface thereof. A thin layer of alloy, the end face of which is cut in a direction transverse to the axis of the wire forms a contact surface to which the silver-metal oxide alloy is exposed, and the thin layer of pure silver or a silver alloy close to pure silver is a wire. And the wire for electrical contact, which is interposed between the caulking contact surfaces of the base metal and the base metal.