JPS59194312A - Method of producing flat cable - 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 The present invention relates to a flat cable used for wiring electronic equipment, communication equipment, etc.

Flat cables are conventionally known as electric wires suitable for complex wiring in electronic/communication equipment, control panels, instruments, etc.

As shown in Fig. 1, a typical structure of such a flat cable consists of cable wires 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3. A so-called ribbon electric wire is known in which the plastic insulating layers 2, 2 of the adjacent cable wires 3, 3 are bonded or fused to form a single body, in which the cable wires 3, 3 are arranged closely in parallel, and each C1e It has the advantage of being separated by color and being able to tear and branch from any point, but because there is no bridge between the core wires, it is necessary to separate all the core wires one by one when attaching them to a connector, etc., for example. Kaa, s-
In addition, when both ends of a ribbon wire are connected and fixed in a twisted state, a restoring force acts due to the elastic action, which causes stress to concentrate at both ends, which can easily cause accidents such as disconnection near the connected ends. However, as the number of core wires increases, the width of the ribbon wire increases, creating a blind spot behind the ribbon wire and reducing work efficiency.

Therefore, it is easy to attach to the connector and has excellent flexibility, and it is easy to separate the wires, and when there are many wires, there are fewer blind spots.As a cable, it can be used as a bridge between many parallel wires. A flat cable with a section was developed and is now widely used.

By the way, when manufacturing a flat cable with such a bridge part using plastic extrusion coating,
Not only is it difficult to distinguish the color of each strand, but it is also not easy to tear apart the strands to separate them.Furthermore, nipples and dies must be made for each pitch and each strand, and flat cables is expensive and impractical.

Also, I know of a flat cable in which multiple conductors are lined up in parallel and glued between the top and bottom with two pieces of plastic tape, but in this case, the wires are not separated by color, and the bonding between the wires is difficult. It is difficult to manufacture a bridge with a narrow pitch of 1.27 wx because it requires a pressure bonding means of a constant width such as a heated roll.

As shown in Figure 2, one method of manufacturing a flat cable that does not have the above drawbacks and allows each strand to be differentiated by color and has the necessary bridge structure is to add a plastic insulating layer on top of the conductor 1. Cable wire 3' coated with 2
ft are arranged in parallel at a constant pitch P, and hot molds 5,
5. Separate each plastic insulation layer 2 by pressing on it. A method has been considered in which the plastic insulating layers 2, 2 of the adjacent strands 3, 3 are softened and bonded to each other to form a bridge part.This bridge part is provided intermittently in the length direction of the flat cable. At the time, the work efficiency was relatively high and we achieved some results, but in order to form the bridge part, the plastic insulating layer in the vicinity had to be softened and deformed, so the insulating layer there was uneven. The thickness of the insulating layer is much thinner than that of the non-bridge part, so the cable's electrical characteristics (withstand voltage of each strand) must be considered as the standard for this thinned part. Not,
Furthermore, a decline in mechanical properties by 1° is also unavoidable.

The present invention has been devised in view of the above-mentioned situation, and provides a cable wire having a plastic insulation layer 2 on conductors 1 arranged in parallel at a constant pitch P as shown in FIG. 3(1). For example, if there is plastic between 3, 3...
Press with a hot mold 5 with a plastic string + A6 interposed. This hot mold 5 has grooves 6, 6, which are large enough to accommodate all the cable wires 3, 3, and pressing flat parts 7, 7 that are located between them and press the plastic intervening body from above and below.
. . constitutes a pair of thermal molds 5. The state in which this hot mold 5 is pressed is the third (9) + (2) K
As shown.

In FIGS. 3(1) and 3(2), the same parts are given the same reference numerals. During this process, the plastic intervening material is softened by the heat of the hot mold and fuses with the plastic insulation 2 of the cable strand 3, and a bridge portion 4 is formed between the pressed flat portions 7, 7. In this case, the width of the bridge can be set by appropriately selecting the width 'ff of the suppressing flat part 7 relative to the thickness of the plastic intervention body.

The structure of the flat cable manufactured in this way is
FIG. 4 shows a case where a plastic string 48 is used as the plastic interposition.

That is, a plurality of cable wires 3 each having a plastic insulating layer 2 provided on a conductor 1 are arranged in parallel at a constant pitch P, and a plastic string is placed between each cable wire 3 along its entire length in the longitudinal direction. The wires 3, 3, . . . are fused to the plastic insulating layers 2, 2, . . . to form a bridge portion 4 with no gap.

Moreover, the case where a short plastic molded body 4B (1/not shown) is used as a plastic intervening material instead of the plastic string is the same as shown in FIG.

That is, a plurality of cable strands 3 with a plastic insulation layer 2f provided on the conductor 1 are arranged in parallel at a constant pitch P, and a short plastic molded body is placed between each strand 3 to extend along the length of the cable. This constitutes a bridge portion 4 which is fused to the plastic insulation layer 2 of the cable wire 3 intermittently in the direction and coupled intermittently.

In order to make the flat cable shown in FIG. 4 above, in the case of a hot mold as a heating means, f'L must be used continuously in the length direction of the cable, so for example, a plurality of This can be done by attaching a hot mold and processing it. To make the flat cable shown in Figure 5, prepare one set of hot molds, attach it to a press machine, and heat-seal intermittently. It can be manufactured by

Although the above description has been made regarding the case where a hot mold is used as the heating means, it is also possible to use a pair of hot rolls. Whether it is a hot mold or a hot roll, it is possible to configure it so that the surface temperature f can be appropriately determined by providing a heating wire or a passage for heating steam inside.

As described above, the present invention manufactures a flat cable by using a plastic intervening body between the cable strands, so it is easy to tear with a relatively simple means, each strand can be separated by color, and the strands can be insulated. Since there are no thin parts in the layer, it is possible to provide a flat cable that not only has no mechanical weaknesses but also has excellent electrical withstand voltage characteristics.

Note that the plastic intervening body used in the present invention is naturally preferably made of the same material as the insulating layer of the cable wire, and its shape may be round, square, etc.1. But that's fine.

[Brief explanation of the drawing]

Figure 1 shows a conventional flat cable (without bridge).
FIG. 2 is a side view (1) and cross-sectional view (2) showing an example of the manufacturing state of a conventional flat cable with a bridge, and FIG. 3 is a perspective view of a flat cable with a bridge according to the present invention. (1) is a cross-sectional view showing the state immediately before pressing the hot mold;
2) is a cross-sectional view showing the state at the time of suppression. Fig. 4 is a perspective view of a flat cable made by the method of the present invention with a bridge provided along its entire length, and Fig. 5 is a perspective view of a flat cable made by the method of the present invention in the length direction. FIG. 2 is a perspective view of a cable with intermittent bridge portions. 1...Conductor 2...Plastic insulation layer 3...Cable wire 4...Bridge section agent
Patent Attorney Mamoru Takeuchi Figure 2 (2)

Claims (3)

[Claims] (1) A plurality of cable strands 3f with a plastic insulating layer 2 covered on the conductor 1 are arranged in parallel, and a plastic intervening body 48 is arranged between the cable strands 3, 3... Then, this plastic intervening body is heated and softened by a pair of heating means having a plurality of grooves 6, 6... formed at a constant pitch and pressing flat parts 7, 7... of the plastic intervening body alternately. , and by pressing from above and below, the plastic insulation layer 2 of the adjacent cable wires 3, 3 is removed.
, 2 to form a bridge portion 4. (2) The method for manufacturing a flat cable according to claim 1, wherein the plastic intervening body is a filamentous body and forms a bridge portion spanning the entire length between the cable strands. (3) The method for manufacturing a flat cable according to claim 1, wherein the plastic intervening body is a short molded body, and the intermittent covering portion 4 is formed between the cable wires 3, 3.