JPS633402B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a conductor and a flat cable using the conductor.

2. Description of the Related Art Conventionally, flat cables have been used as electric wires suitable for complex wiring of electrical equipment, electronic equipment, etc. This flat cable is made by arranging multiple conductors horizontally in parallel and insulating them as one piece, and has superior flexibility compared to a round cable with the same number of conductors. Twisted wire is used to increase the flexibility of the wire and to prevent wire breakage due to repeated bending. However, if the ends of such flat cables are exposed, the twisted wires may come apart, making connection difficult. In addition, when a connector is attached and connected, there is a concern that the stranded wires are likely to break due to the press-fitting of the terminal fittings of the connector, and that the contact is not reliable. Therefore, a conducting wire as shown in FIG. 1 has been proposed in which the outer periphery of the stranded wire is coated with plating (Japanese Utility Model Publication No. 55-15644 and Japanese Utility Model Application Publication No. 57-9119). This conducting wire is a stranded wire 1 made of copper wire or the like, with a thin plating 2 made of tin, zinc, etc. applied to the outer periphery, and has the flexibility of a stranded wire, and
The strands 3 of the twisted wires are less likely to come apart, and the reliability of contact with the terminal fittings of the connector is also high.

However, when plating stranded wires using, for example, thermal plating, the plating metal fills up to the gaps between the wires inside the stranded wires, impairing the flexibility of the stranded wires. In case,
There is a drawback that plating is difficult to adhere to the recessed portions of the stranded wire (between adjacent strands of the stranded wire). In other words, if the recesses are not plated, it will not be possible to prevent the strands from falling apart, and plating for a long time in order to fully plate the recesses will prevent the protrusions of the stranded wires from forming. This will make the plating coating thicker, which will impair the flexibility of the stranded wire.

The present invention has been made against the background of the above-mentioned circumstances, and aims to provide a conducting wire in which the recesses of the stranded wire are reliably covered and excellent in flexibility, and a flat cable using this conducting wire. A connecting layer made of a thermoplastic resin or thermosetting resin having good affinity with the stranded wire is provided in the recess of the strand so as to integrate the strands on both sides of the recess. .

The present invention will be described below based on embodiments shown in the drawings.

First, to explain the conductive wire of the present invention, FIG. 2 shows one embodiment, in which a stranded wire 1 made of strands 3 such as copper wire is placed in a recess 4 in which strands 3 and 3 are placed on both sides of the recess 4. The structure includes a connecting layer 5 made of urethane resin or the like for integrating the parts. The connecting layer 5 has a bulging shape, for example, on a common tangent between the adjacent strands 3 (see FIG. 3), and can be removed by hooking it on a finger. Further, the connection layer 5 can be easily removed at a temperature below the melting temperature (260 to 270°C) of soldering metals such as tin and zinc.

Such a conductive wire 6 is obtained by, for example, a dipping method (a method in which a conductive wire is passed through a plastic sol and squeezed) using capillary phenomenon, and the connecting layer 5 is made of a material that has an affinity for copper, such as urethane resin. If the material is of good quality, it can be deposited intensively in the recess 4 of the strand 1. Moreover, connection layer 5
Since it is a flexible material, even if it gets into the gaps between the wires inside the stranded wire 1, the flexibility of the stranded wire 1 will not be significantly impaired.

FIG. 4 shows another embodiment of the present invention, in which a connecting layer 5' is provided in the recess 4 of the stranded wire 1 to integrate the strands 3 on both sides of the recess 4. At the same time, an exposed surface 7 of the stranded wire 1 is provided in a portion of the stranded wire 1 excluding the recessed portion 4. Since electrical continuity is established through the exposed surface 7 of such a conducting wire 6', contact reliability is increased.

Next, a flat cable using such a conductor will be explained.

That is, FIG. 5 shows one embodiment, and this flat cable has a structure in which a plurality of the above-mentioned conducting wires 6 are arranged horizontally in a row, and an insulating coating 8 of vinyl chloride or the like is integrally applied thereon. ing.

For example, when the end of this flat cable is inserted into a terminal hole of a printed circuit board and soldered, the insulation coating 8 of the end of the flat cable is
Remove and speak out. Since the conductive wires 6 taken out at this time are integrated by the connection layer 5, the strands 3 of the stranded wire 1 do not come apart and can be easily inserted into the terminal hole. Furthermore, since the connecting layer 5 is easily melted during soldering, it does not prevent the conduction between the stranded wire 1 and the terminal hole.

Furthermore, even when the terminal plate of the connector is press-fitted into the end of the flat cable, the strands 1 do not easily break down, so the contact reliability between the terminal plate and the strands 1 is high.

Note that the connection layer 4 has a chemically stable molecular structure such as polyethylene, and the strands 1
If the compatibility is not good, the conductive wire 6 can be obtained by an extrusion coating method rather than a dipping method, for example by attaching a rotary die to an extruder.

Furthermore, by using the plastic powder coating method (a method in which plastic powder is applied to the conductor in an electrostatic atmosphere and treated in a furnace to obtain a uniform layer of plastic), it is possible to use either thermoplastic or thermosetting resin. Also, the connecting layer 4 can be efficiently formed with a uniform thickness, and the conductor 6 can be obtained.

As explained above, according to the present invention, a connection layer made of plastic is provided in the recess of the stranded wire so as to integrate the wires on both sides of the recess, and a plurality of conductive wires formed as described above are arranged in a horizontal line. By arranging them parallel to each other and integrally applying an insulating coating to them, the following effects can be obtained.

It is possible to prevent the twisted wire from breaking without impairing the flexibility of the twisted wire.

It has better productivity than metal plating on stranded wires and can be produced at a lower cost.

The strength of the stranded wire against repeated bending etc. can be increased.

A flat cable that is easy to connect and has high contact reliability can be obtained.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view of a conventional conducting wire, Figures 2 and 3 are examples of the conducting wire of the present invention, Figure 2 is a cross-sectional view, and Figure 3 is an enlarged view of the main parts. 4 is a cross-sectional view showing another embodiment of the conducting wire of the present invention, and FIG. 5 is a perspective view showing an embodiment of a flat cable using the conducting wire of the present invention. DESCRIPTION OF SYMBOLS 1... Twisted wire, 2... Plating coating, 3... Element wire, 4... Recessed part, 5... Connection layer, 5'... Connection layer,
6...Conducting wire, 6'...Conducting wire, 7...Exposed surface, 8...
...Insulating coating.

Claims (1)

[Scope of Claims] 1. In a conducting wire formed by twisting a plurality of strands 3 together, the strands 3 are twisted together so that adjacent ones of the strands located on the outer periphery of the conducting wire are in line contact with each other. A conductive wire comprising a connecting layer 5 made of plastic that integrates the wires on both sides of the recess in a recess 4 formed between the wires on the outside of a stranded wire 1 with a space provided inside. 2. In a conducting wire made by twisting a plurality of wires 3 together, a space is created inside the wire by twisting adjacent ones of the wires located on the outer periphery of the wire so that they are in line contact with each other. A plurality of conducting wires 6 are arranged horizontally in a line, and a connection layer 5 made of plastic is provided in a depression 4 formed between the strands on the outside of the stranded wire 1 to integrate the strands on both sides of the depression. The flat cables are lined up and integrally coated with insulation coating 8.