JPH0354801B2 - - Google Patents

Description

[Detailed description of the invention]

(Technical Field) The present invention relates to a thin electric wire for equipment used between or within equipment such as electrical equipment or electronic equipment. (Background Art) In electrical connections between or within equipment such as electronic equipment, medical equipment, and audio equipment, along with the demand for smaller and lighter equipment, the electric wires used are becoming increasingly thinner and mechanically The required characteristics have become increasingly strict both electrically and electrically. Mechanically, it is required to be difficult to break due to tensile force or repeated bending during wiring and use, and electrically, it is required to have high efficiency for high frequency signals, that is, at least the outer periphery of the conductor must be highly conductive. In addition, from the viewpoint of improving workability, the product is required to be flexible. Conventionally, the following electric wires have been used as thin electric wires for these devices, but each has the following drawbacks. For example, thin copper wires made of tough pitch copper, oxygen-free copper, etc., are usually softened during hot-dip tin plating even if hard copper wires are used. This results in an annealed copper wire that lacks mechanical strength. Even if it is not softened (not glazed), it will lack flexibility. For example, wires made of work-hardening alloys such as Cu-Sn and Cu-Zn have strength, but generally have low conductivity and low efficiency for high-frequency signals.
It's also not supple. For example, wires made of age-hardening alloys such as Cu-Be, Cu-Cr, and Cu-Zr can
The mechanical properties are good, with a good balance between strength and flexibility, but if the final size is thin, heat treatment for refining is difficult and variations in properties tend to increase. Furthermore, intermediate annealing during processing into a thin wire is likely to be difficult. Copper-coated iron (steel) wire lacks reliability due to the presence of iron due to its magnetic properties, and although it is strong, it is difficult to draw into thin wire, and the iron tends to soften during processing into thin wire. At the required temperature softening, the problem of tight contact between the wires arises. As mentioned above, the conventional thin electric wires for equipment have been unsuitable as thin electric wires for equipment called "electronic wires." (Disclosure of the invention) The present invention has been made in view of the above circumstances, and
By appropriately combining the materials of the composite jacket material and the core material, it is possible to provide a thin electric wire for equipment that has high strength and flexibility, has high efficiency for high-frequency signals, and is easy to manufacture. It is. The thin electric wire for equipment of the present invention is used for computers, OA
Thin wires used for connections, wiring, etc. between or within electrical or electronic equipment such as equipment, communication equipment, medical equipment, audio equipment, etc., consisting of a single wire or a stranded wire made by twisting multiple wires of these wires together. The cross-sectional shape of the single wire may be round, oval, square, other polygons, or other irregular shapes. In the present invention, the copper constituting the outer covering material is pure copper called electrical copper, such as tough pitch copper, oxygen-free copper, and deoxidized copper. Further, the copper alloy constituting the core material is a copper alloy having a higher softening temperature and greater strength than the above-mentioned copper, such as brass, red copper, phosphor bronze, beryllium copper, silicon copper, and cypronickel. The thin electric wire for equipment of the present invention is used as a composite wire consisting of the above-mentioned jacket material and core material, or as a stranded wire thereof. It is often used after being plated with tin, solder, etc. 1 to 3 are cross-sectional views showing examples of the electric wire of the present invention. In FIG. 1, a brass wire 1 is covered with tough pitch copper 2 as an outer covering material. In FIG. 2, oxygen-free copper 4 is coated around the phosphor bronze wire 3 as a covering material, and a tin plating layer 5 is further plated thereon. In FIG. 3, oxygen-free copper 7 is coated around the beryllium copper wire 6 as a covering material, and a tin plating layer 8 is further plated thereon. The thin electric wire of the present invention is composed of the jacket material and the core material as described above, so that the outer layer has high conductivity, so the efficiency of high frequency signals is high, and the outer layer is soft, so it is flexible and the core material is flexible. Because the material has high strength, it is difficult to break under simple tensile force, and has excellent characteristics as a thin electrical wire for equipment. Next, in order to manufacture the electric wire of the present invention, the usual method of covering the core material with a sheath material, the pipe fitting method,
A copper plating method, an extrusion coating method, a method in which a copper tape is formed into a pipe shape around a core material and crimped, etc. are used. In this case, the copper of the jacket material has good workability and is easy to join with copper alloys, so it is easy to manufacture the composite material, and the subsequent area reduction processing such as wire drawing is also easy. No complicated heat treatment is required. Furthermore, since the core material has greater strength than the outer covering material, the strength of the core material is much higher than that of the outer covering material. In addition, the final size composite wire is subjected to softening treatment if necessary, softening only the copper of the outer sheath material to increase its flexibility, while hardly softening the copper alloy of the core material.
Maintain strength. This softening may be done by applying electricity or by heating with a tube furnace or the like. Next, when hot-melting tin, solder, etc. to the final size fine composite wire that has undergone the area reduction process as described above, the wire is heated by immersion in a hot-melting bath, so the outer sheathing material is heated. Only copper that softens at relatively low temperatures (eg, tough pitch copper, oxygen-free copper, etc.) is softened even if it is a soft material, and the copper alloy of the core material is hardly softened. In this case, the temperature of the molten plating bath is set to be higher than the hardening temperature of the copper of the outer covering material and lower than the softening temperature of the copper alloy of the core material. According to such a manufacturing method, properties meeting the final required properties can be obtained during melt welding, so there is no need to perform a separate softening treatment for the final size, and this process can be omitted. In addition, if the above-mentioned softening effect cannot be obtained only by melt plating, the above-mentioned softening treatment may be performed separately before melt plating. It is optimal that the outer sheath material of the conductor after tempering has a microvitkers hardness of 50 to 100, and that of the core material 100 to 190. (Example) A composite material with an outer diameter of 10 mm, consisting of a brass (70% Cu-30% Zn) rod fitted with a tough pitched copper tube, was wire-drawn.
Intermediate annealing at 450℃ for 2 hours at 1.6mmφ,
The wire was drawn to a diameter of 0.1 mm. This wire was subjected to a softening treatment, and only the tough pitch copper of the sheath material was softened under conditions that the strength of the brass core material was not significantly reduced, thereby producing a thin electric wire No. 1 according to the present invention as shown in FIG. Oxygen-free copper tape was formed into a pipe shape around a phosphor bronze wire, the seam was welded, and the wire was fitted and drawn to create a composite material with an outer diameter of 8 mm and a core diameter of 6 mm. This composite material was subjected to intermediate annealing (also adhesion improvement treatment) at 420°C for 4 hours at a diameter of 2.6 mm, and wire-drawn to a diameter of 0.05 mm. This wire is tin-plated using a regular continuous plating device at a melt-melting bath temperature of 280°C to soften only the oxygen-free copper of the outer jacket material, resulting in a thin wire according to the present invention as shown in Figure 2. Physical wire No. 2 was created. In addition, during the manufacturing process of these thin electric wires No. 1 and No. 2, there were few occurrences of wire breakage, there was little troublesome heat treatment, and the manufacturing was easy. In the same manner as in the production of thin electric wire No. 2, a 0.05 mmφ tin-plated oxygen-free copper coated beryllium copper wire (thin electric wire No. 3 according to the present invention) was produced as shown in FIG. The tensile strength of the obtained thin electric wire and the micro-Vickers hardness of the core material and sheathing material are shown in Table 1.

[Table] From Table 1, it can be seen that all have high tensile strength, the outer covering material is soft and pliable, and the core material has high hardness. Next, seven thin wires No. 2 and No. 3 were twisted together to form a stranded wire conductor. A vinyl insulation coating is applied to the stranded wire using No. 2,
The wire used for wiring between the VTR body and the camera was thin, light, and flexible, and did not easily break even after repeated bending. Moreover, the high conductivity of the outer covering material ensures high reliability in transmitting high-frequency signals. In addition, the stranded wire using No. 3 is coated with a flexible vinyl insulation coating, and when used for the oxygen sensor part and the cord of the main body of medical equipment, it is a flexible, mechanically and electrically reliable conductor. It was hot. (Effects of the Invention) The thin electric wire for equipment of the present invention configured as described above has the following effects. (a) The outer covering material is made of copper, and the core material is made of a copper alloy that has a higher softening temperature and greater strength than the copper, so the core material has high strength, so it is strong as an electric wire and is difficult to break. , and the outer covering material is soft,
Due to the large elongation, the wire is flexible and resistant to repeated bending, and the conductivity of the jacket material is high, so the efficiency of high frequency signals is high, and since there is no iron etc., there is no negative magnetic effect. (b) The copper of the outer sheath material and the copper alloy of the core material are easy to join, and it is also easy to reduce the area of the composite material, and since only the copper of the outer sheath material can be softened by softening treatment, the final size It is easy to heat the wire, and there is no need for troublesome heat treatment such as aging treatment, so it is easy to manufacture electric wires.

[Brief explanation of drawings]

1 to 3 are cross-sectional views showing embodiments of the conductor of the present invention. 1... Brass wire, 2... Tough pitch copper, 3... Phosphor bronze wire, 4, 7... Oxygen-free copper wire, 5, 8... Tin plating layer,
6...Beryllium copper wire.

Claims (1)

[Scope of Claims] 1. The outer covering material made of copper has a micro-Vickers hardness of 50 to 100, and the core material made of a copper alloy has a curing temperature higher than that of the outer covering material, and has a micro-Vickers hardness of 100 to 190. A thin electrical wire for equipment, characterized by comprising: 2. A thin electric wire for equipment according to claim 1, which has a plating layer made of tin or solder on the outer covering material.