JPH0660745A - Manufacture of flat cable - Google Patents

Abstract

PURPOSE:To increase fusion bonding strength at both ends of a fusion bonding part of a flat cable in its longitudinal direction without breaking cores of a plurality of coated core wires and/or deteriorating their electrical characteristics. CONSTITUTION:The sheath 14 of each of a plurality of core wires 12 is heat fusion bonded by a heat fusion bonding plate 22. This heat fusion bonding plate 22 has its both ends thicker than other parts so as to have a concave longitudinal cross section that is formed by convex parts 22A provide on the both ends and a concave part 2B. Each convex part 22A is pushed to both ends of each of the plural coated core wires 12 serving as parts to become fusion bonding parts 18.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flat cable used for electronic equipment such as computers and industrial equipment,
The present invention relates to an improvement in a method for manufacturing a flat cable in which a plurality of coated core wires are intermittently heat-sealed in the longitudinal direction.

[0002]

2. Description of the Related Art Generally, in electronic equipment such as computers and industrial equipment, a flat cable having a fusion-bonded portion for facilitating terminal processing work and a non-fusion-bonded portion for facilitating wiring work. Is used. This type of flat cable is manufactured by forming a fused portion by fusing the coatings of a plurality of coated core wires to each other. There are various methods for fusing the coatings of a plurality of coated core wires to each other in order to form the fusion-bonded portion, but a typical method is fusion by heat. In this method, as shown in FIG.
As shown in FIG. 5, a plurality of coated core wires 12 to be fused, which are supplied from a core wire supply means 40 such as a drum, are arranged in parallel on a plane, and the coating 14 of the plurality of coated core wires 12 is heat-sealed to a plate 22. After it is heat-sealed by the above, it is cooled by the cooling means 42 for blowing cooling air, and finally, the plurality of coated core wires 12 are taken by the take-up means 44 and wound around the take-up means 46 to manufacture the flat cable 10. There is.

As described above, when a plurality of coated core wires are fused with each other using the heat fusion plate, conventionally, as shown in FIGS. 6 and 7, the contact surface with the plurality of coated core wires 12 is flat. By using the heat-sealing plate 22 as described above, and pressing the heat-sealing plate 22 from above and below onto the plurality of coated core wires 12 to be fused, the coatings 14 of the plurality of coated core wires 12 are thermally fused to each other. I wore it and manufactured the flat cable 10. However, in the flat cable manufactured by this conventional manufacturing method, the strength of the fused portion is weaker in both longitudinal end portions than in the central portion of the fused portion, and cracks occur at the interface with the non-fused portion. It was happening.

[0004]

In order to increase the strength of both ends in the longitudinal direction of the fusion-bonded portion so as not to cause this crack, it is conceivable to increase the temperature, fusion-time and pressure of the fusion-bonded plate. However, the coating of a plurality of coated core wires is melted more than necessary, and the cores of the plurality of coated core wires are thermally and mechanically damaged, and particularly when the plurality of coated core wires are foam insulated wires, There was a risk that the electrical characteristics would deteriorate.

The object of the present invention is to avoid the above-mentioned drawbacks and to fuse the longitudinal ends of the fused portion without damaging the cores of a plurality of coated core wires to be fused or deteriorating the electrical characteristics. It is an object of the present invention to provide a method for manufacturing a flat cable capable of increasing strength.

[0006]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention arranges a plurality of coated core wires in parallel on a plane and heats the coating of the plurality of coated core wires by heat fusion means. In the method for producing a flat cable by intermittently heat-sealing the material in the longitudinal direction by using a heat-sealing plate having longitudinal concave sections whose both longitudinal ends are thicker than other portions, as the heat-sealing means. The present invention provides a method for manufacturing a flat cable, which comprises heat-sealing a plurality of coated core wires.

[0007]

As described above, when the coatings of the plurality of coated core wires are fused by the thermal fusion bonding plate having longitudinal concave portions whose longitudinal ends are thicker than other portions, the temperature of the thermal fusion bonding plate, the fusion time, Even if the pressure is not specially increased, this convex portion is in intimate contact with both ends of the coated core wires in the portion to be the fusion-bonded portion, so that both ends of the fusion-bonded portion, which require high strength, are made even stronger. Since they can be fused, the strength in the vicinity of the fused interface between the fused portion and the non-fused portion can be increased without damaging the cores of the plurality of coated core wires or affecting the electrical characteristics.

[0008]

Embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 schematically shows a state in which a method for manufacturing a flat cable according to the present invention is carried out.
Is manufactured by arranging a plurality of coated core wires 12 in parallel on a plane and intermittently fusing the coatings 14 of the plurality of coated core wires 12 with a heated heat fusing means 16 over the cable longitudinal direction. . As shown in FIG. 4, the flat cable 10 manufactured in this manner has a fusion splicer 18
And the non-fusing portions 20 are alternately provided.

As shown in FIG. 1, a plurality of coated core wires 12 to be fused are supplied from a core wire supplying means 40 and arranged in parallel on a plane by an unillustrated aligning means.
The flat cable 10 is manufactured by fusing the coatings 14 of the plurality of coated core wires 12, cooling them by the cooling means 42, finally taking them by the take-up means 44 and winding them around the winding means 46. The plurality of coated core wires 12
As shown in FIG. 5, an insulating core wire 3 formed by coating a conductor 1 with an insulator 2, a sheath core wire 5 having a sheath 4 further coated thereon, or a coaxial cable (not shown) is used. be able to. In the present invention, coating 1
4 is a general term for the insulator 2, the sheath 4, or the jacket of a coaxial cable (not shown).

In the present invention, as shown in FIG. 1, as the heat fusion means 16, a pair of heat fusion plates 22 provided so as to sandwich the plurality of coated core wires 12 from above and below are used to provide a plurality of coatings. The coating 14 of the core wire 12 is heat-fused to form a fused portion 18. As shown in FIG. 2, the heat-sealing plate 22 has both longitudinal end portions 22a thicker than the other portions, and has a concave vertical cross section. That is, as shown in FIG.
A recess 22B for fusing the central portion 18b (see FIG. 4) of FIG.
And a convex portion 22A which is provided at both ends of the concave portion 22B and which fuses both longitudinal end portions 18a (see FIG. 4) of the fused portion 18 to each other.
And consists of. As shown in FIG. 2, the longitudinal width of the concave portion is set to an appropriate width so as to contact only both ends of the fusion-bonding portion 18, and the height difference between the convex portion 22A and the concave portion 22B is shown in FIG. As shown, about 0.1 mm to 0.3 mm is desirable.

Since the convex portion 22A is formed so as to project thicker than the concave portion 22B, the entire heat-sealing plate 18 is melted without particularly increasing the temperature, the welding time and the pressure of the heat-sealing plate 18. When pressed against the plurality of coated core wires 12 to be attached, the ends of the portions of the plurality of coated core wires 12 that should be the fused portions 18 come into closer contact with each other.
Both longitudinal end portions 18a of 8 are firmly fused, and as a result, the strength in the vicinity of the fused interface between the fused portion 18 and the non-fused portion 20 is increased. On the other hand, when heat-sealing the coatings 14 of the plurality of coated core wires 12, it is not necessary to particularly increase the temperature, the fusion-bonding time, and the pressure of the heat-fusion plate 18, so that the cores of the plurality of coated core wires 12 are damaged. And does not affect the electrical characteristics.

In the embodiment shown in FIG. 1, when fusing the coatings 14 of the plurality of coated core wires 12 which are not yet fused with each other, the both ends are thicker than the other portions and the vertical cross section has a concave shape. Although only the heat-sealing plate 18 having it is used, first, after the heat-sealing plate having a flat surface in contact with the plurality of coated core wires 12, the coating 14 of the plurality of coated core wires 12 is fused,
The flat cable 10 may be manufactured by using the heat-sealing plate 18 having both ends thicker than other portions and having a concave vertical cross-section and further fusing the fusion-bonding portions 18. In this case, the first heat fusion is weakened, and the second heat fusion is performed so as to reinforce the strength of only both ends of the fused portion. In addition,
In the embodiment in which the coatings 14 of the plurality of coated core wires 12 are fusion-bonded twice, the heat-fusion means 16 is used as the heat-fusion means 16 at the time of the first fusion, instead of the above-mentioned heat-fusion plate. A roll or the like may be used.

Next, a specific example of the present invention will be described.
Table 1 shows an outer diameter of 0.635 m obtained by coating PVC on a tin-coated wire formed by twisting seven conductors having an outer diameter of 0.1 mm as a coated core wire.
m of insulated electric wires, the insulated electric wires are arranged in parallel on a plane of 100 pieces, and an intermittent flat cable manufactured by heat-sealing the coating of each insulated electric wire according to two different embodiments of the present invention. It shows the peel strength between adjacent insulated wires. The length of each fused portion in the longitudinal direction is 100 m.
m.

[0014]

[Table 1]

First, as can be seen from Table 1, a specific example 1
As described above, a heat-bonding plate having a total length of 100 mm having both longitudinal end portions thicker than other portions and a concave vertical cross section is used, and each of the convex portions provided at both ends of the heat-fusion plate is When the length is 10 mm, the thickness is 0.2 mm thicker than the recess, and the insulated wire is heated uniformly at a temperature 10 ° C. higher than the softening temperature of PVC as the coating, and the insulated wire is heated for 15 seconds, the flat cable produced is The peel strength between adjacent insulated wires was 350 g / 100 mm.

Also from Table 1, as in Example 2, first, the insulation wire is heat-sealed for 15 seconds by a heat-sealing plate having a uniform thickness and a total length of 100 mm, and then the longitudinal section is concave. Using a heat-sealing plate having a length of 100 mm and having a length of 100 mm, the convex portions provided at both ends of the heat-sealing plate have a length of 10 mm and a thickness of 0.5 mm greater than that of the concave portion to soften the PVC coating. When the insulated wire was heated uniformly at a temperature 10 ° C. higher than the temperature and the insulated wire was further heated for 15 seconds, the peel strength between the adjacent insulated wires of the manufactured flat cable was 400 g / 100 mm.

Next, Table 2 shows that the same insulated wires as those of the first and second specific examples of the present invention were used as coated core wires, and these insulated wires were arranged in parallel on the plane of 100 wires, and the conventional method was used. 3 shows the peel strength of an intermittent flat cable manufactured by heat-sealing the coating of each insulated wire according to Comparative Example 1.

[0018]

[Table 2]

As can be seen from Table 2, in Comparative Example 1, the heat-bonding plate having a flat contact surface to the insulated electric wire, which is the coated core wire, has a uniform thickness, so that the softening temperature of PVC as the coating is higher than that of PVC. When the insulated wire is heated uniformly at a temperature 10 ° C higher than the above, and the insulated wire is heated for 15 seconds, the peel strength between the adjacent insulated wires of the manufactured flat cable is 250 g / 100 m.
It was m.

The peel strength of the intermittent flat cable obtained in Example 1 and Example 2 of the present invention shown in Table 1 above,
As will be understood by comparing the peel strengths of the intermittent flat cables obtained in Comparative Example 1 of the prior art shown in Table 2 above,
According to the present invention, the peeling strength between adjacent insulated electric wires is significantly improved as compared with the prior art, and the welding strength at both ends in the longitudinal direction of the fused portion is increased. Strength near the interface is improved.

In addition, except that the heat fusion time is 20 seconds,
When a fused portion was formed under the same conditions as in Comparative Example 1 above to produce an intermittent flat cable, PVC as a coating was fused more than necessary, and the appearance of the fused portion of the intermittent flat cable was significantly deteriorated. This indicates that, in order to increase the strength of both ends in the longitudinal direction of the fusion-bonded part, if the fusion-bonding time is lengthened, the insulated wire is damaged. It is shown that it is possible to increase the strength of both ends in the longitudinal direction of the fusion-bonded portion without affecting the coated core wire, without increasing the time.

[0022]

As described above, according to the present invention, as described above, the plurality of coated core wires are fused by the heat-fusion plate having a longitudinal cross-section with a concave longitudinal end portion which is thicker than the other portions. Even if the temperature, the fusing time, and the pressure of the heat-fusing plate are not particularly increased, this convex portion is in close contact with both ends of the plurality of coated core wires in the portion to be the fusing portion, so high strength is required. The both ends of the fusion-bonded part can be fused more firmly, and therefore, without damaging the cores of the plurality of coated core wires or affecting the electrical characteristics, the fusion-bonded part and the non-fusion-bonded part There is a practical benefit of increasing the strength near the fusion interface.

[Brief description of drawings]

FIG. 1 is a schematic overall view showing a state in which a method for manufacturing a flat cable of the present invention is carried out.

FIG. 2 is a side view showing a state in which the heat fusion plate used in the method of the present invention is pressed against a plurality of coated core wires.

FIG. 3 is a partially enlarged side view of the heat fusion plate used in the method of the present invention.

FIG. 4 is a top view of a general intermittent flat cable.

FIG. 5 is a cross-sectional view of a plurality of coated core wires that are heat-sealed according to the present invention.

FIG. 6 is a perspective view showing a state in which a heat fusion plate used in a conventional technique is pressed against a plurality of coated core wires.

FIG. 7 is a side view showing a state in which the heat fusion plate used in the conventional technique is pressed against a plurality of coated core wires.

[Explanation of symbols]

 Reference Signs List 10 flat cable 12 a plurality of coated core wires 14 coating 16 heat fusion means 18 fusion bonding portion 18a fusion bonding portion central portion 18b both ends of fusion bonding portion 20 non-fusion bonding portion 22 heat fusion bonding plate 22A convex portion 22B concave portion 22a heat Both ends of the fusion plate

Claims (1)

[Claims] 1. A flat cable is obtained by arranging a plurality of coated core wires in parallel on a plane and intermittently heat-sealing the coating of the plurality of coated core wires in the longitudinal direction by a heated heat-sealing means. In the method for producing, a flat characterized in that the plurality of coated core wires are heat-sealed by using a heat-sealing plate whose longitudinal cross section is concave in which both longitudinal ends are thicker than other portions as the heat-sealing means. Cable manufacturing method.