JP2002319319A - Parallel twin-core shielded electric wire - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a parallel twin-conductor shielded electric wire in which a shielded conductor is formed by winding a metal foil tape, and an outer shell formed on the outer circumference is made thin. SOLUTION: This parallel twin-conductor shielded electric wire is manufactured in such a way that at least one drain conductor 15 is longitudinally attached to a pair of insulating electric wires 11 arranged in parallel, the metal tape 17 is wound onto the insulating electric wires 11 and the drain conductor 15 in a lump to form the shielded conductor 14, and the outer circumference of the shielded conductor is covered with the outer shell. The outer shell 16 is formed by winding a plastic tape 18.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shielded electric wire used for transmitting a digital signal, and more particularly to a shielded electric wire having two parallel cores.

[0002]

2. Description of the Related Art In recent years, with the development and demand expansion of digital information communication, shielded wires have been frequently used for signal transmission in offices, premises, and other various information electronic devices. As a shielded wire for communication, a shielded wire of a two-core parallel type is used, and a large number of these wires are assembled into a multi-core cable. The shielded electric wire is provided with a shielded conductor and further covers the outer periphery of the shielded conductor with a jacket, so that the shielded electric wire has to be thicker than a normal unshielded insulated electric wire. However, due to the increased use of shielded wires, there has been a demand for a smaller wiring for high-density mounting due to space saving of wiring and miniaturization of electronic equipment.

[0003] A parallel two-core shielded electric wire is a pair of a single-core shielded electric wire in which a plurality of conductive wires are formed into a shielded conductor by a horizontal or braided wire on an insulated electric wire in which an inner conductor is covered with an insulating material. , And can be configured by covering with a common jacket. However, when a shield structure using a braided conductive wire or the like is used, the braided wire material needs to have a certain thickness, so that there is a limit in reducing the diameter of the electric wire, and it is not suitable for realizing high-density mounting.

Therefore, it is known that the diameter of the shield conductor is reduced by forming the shield conductor by winding a metal foil tape. As this type of form, there are generally three types of structures as shown in FIG. In the figure, 1 is an insulated wire, 2 is an inner conductor, 3 is an insulator, 4 is a shield conductor, 5 is a drain conductor, and 6 is a jacket. The insulated wire 1 is obtained by covering the inner conductor 2 with an insulator 3.

FIG. 5A shows a pair of insulated wires 1 arranged in parallel, and a drain conductor 5 for terminal connection is vertically attached to a lateral side of one of the insulated wires. It has a structure in which the outer circumference of the shield conductor 4 is covered with a jacket 6 in a lump. FIG. 5 (B)
Has a structure in which a pair of insulated wires 1 are arranged in parallel, a drain conductor 5 is vertically attached to the lateral side surfaces of both insulated wires, and a shield conductor 4 and a jacket 6 are formed in the same manner as in FIG. is there.
FIG. 5C shows a case where a pair of insulated wires 1 are arranged in parallel, and a drain conductor 5 is longitudinally attached to a central portion where both insulated wires are in contact with each other. Similarly to FIG. It is of a formed structure.

Further, as shown in FIG. 6A, a large number of the above-described parallel two-core type shielded wires are bundled to form a multi-core.
A circular cable or a ribbon-shaped cable as shown in FIG. 6B is used for wiring in the office and on the premises. In wiring in an electronic device, an electric connector is connected to these and used as a harness.

[0007] As shown in FIG. 7, the shielded electric wire having any structure shown in FIG. 5 has a pair of insulated electric wires 1 and a drain conductor 5 for terminal connection vertically attached thereto.
Are wound and integrated, and the wound metal foil tape 7 is used as the shield conductor 4. The metal foil tape 7 forming the shield conductor 4 has a structure in which a conductive foil 7a of aluminum or copper having good conductivity is laminated on a base material 7b of a polyester plastic film by vapor deposition, affixing or the like. .

A jacket 6 is formed on the outer periphery of the shield conductor 4 by extrusion coating with a coating forming die. Jacket 6
As the resin material of, a thermoplastic resin such as polyethylene, polyvinyl chloride, and a fluororesin is used. In the case of a parallel two-core shielded wire, a thin-walled extrusion coating is difficult due to its outer diameter, and therefore, There was also a limit to the reduction in the diameter of shielded wires.

[0009]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has a shield conductor formed by winding a metal foil tape and a thin outer jacket of the shield conductor. And parallel 2 with a reduced diameter
The task is to provide a shielded core wire.

[0010]

According to the present invention, there is provided a parallel two-core shielded wire in which at least one drain conductor is vertically attached to a pair of insulated wires arranged in parallel, and the insulated wire and the drain conductor are collectively combined. A shielded conductor wound by a metal foil tape to form a shielded conductor, wherein the outer periphery of the shielded conductor is covered with a jacket, wherein the sheath is formed by winding a plastic tape around the shielded conductor.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows an example in which a metal foil tape is wound horizontally (hereinafter referred to as spiral winding) around a shield conductor.
1 shows an example of forming a shield conductor of a shielded electric wire, and FIG.
(B) shows an example of forming a jacket. In the figure, 11 is an insulated wire,
12 is an internal conductor, 13 is an insulator, 14 is a shield conductor,
Reference numeral 15 denotes a drain conductor, 16 denotes a jacket, 17 denotes a metal foil tape, and 18 denotes a plastic tape.

[0012] The parallel two-core shielded wire of the present invention, first,
As shown in FIG. 1A, a pair of insulated wires 11 in which an inner conductor 12 is insulated by an insulator 13 are arranged in parallel, and a drain conductor 15 is vertically attached to a lateral side of one of the insulated wires. 17 is spirally wound and held and fixed.
The wound metal foil tape 17 is attached to the shield conductor 14.
And is grounded via a drain conductor 15 to a ground terminal or the like.

Next, as shown in FIG. 1B, a polyester plastic tape 18 is provided on the outer periphery of the shield conductor 14 in place of extrusion coating with a conventional coating molding die.
Is wound in a spiral winding to form a jacket 16.
The formation of the jacket 16 by winding the plastic tape 18 can be applied to all parallel two-core shielded wires having the structure shown in FIGS. 5A, 5B, and 5C. The winding direction is preferably opposite to the winding direction of the metal foil tape 17.

FIG. 2 shows an example in which the shield conductor 14 is wound vertically with a metal foil tape 17 (hereinafter referred to as cigarette winding). 2, a pair of insulated wires 11 in which inner conductor 12 is insulated by insulator 13 are arranged in parallel, and a drain conductor 15 is vertically attached to the lateral side surface of one of the insulated wires, similarly to the configuration of FIG. . The metal foil tape 17 is wound by cigarette winding to hold and fix the pair of insulated wires 11 and the drain conductor 15. The wound metal foil tape 17 is electrically contacted with the drain conductor 15 over the entire length to form the shield conductor 14. Shield conductor 14
1, a polyester plastic tape 18 is spirally wound around the outer periphery of
6 is formed. By forming the metal foil tape 17 into a cigarette winding, the productivity is improved because the tape winding head has only to be one set forming the jacket 16.

FIG. 3 is an enlarged sectional view of the shielded electric wire shown in FIG. 1 and FIG. 2, and the thickness of the shield conductor 14 and the jacket 16 is exaggerated for easy understanding. As the inner conductor 12 of the insulated wire 11, a single wire or a stranded wire formed of an aluminum or copper good conductor can be used. Alternatively, tin or silver plated on the surface of the internal conductor 12 may be used. When used for a high-frequency line, the current is biased to the conductor surface due to the skin effect, and therefore, it is desirable that the conductor is plated with a low-resistance conductive material.
As the insulator 13, various electric insulators such as highly foamed polyethylene can be used.

The drain conductor 15 is the same as that used for the inner conductor 12, and may be a single wire or a stranded wire made of an aluminum or copper good conductor. The thickness of the drain conductor 15 may be the same as that of the inner conductor 12.
Is held and fixed to the outer surface of the insulator 13 by a shield conductor 14 formed by winding a metal foil tape,
The conductor foil 14a is uniformly and reliably contacted over the entire length,
A good electrical connection can be formed. This allows
The thin foil-shaped shield conductor 14 can be reliably grounded to a ground terminal or the like via the drain conductor 15.

A metal foil tape 17 for forming the shield conductor 14 is formed of a conductive foil having good electrical conductivity such as copper, aluminum or copper-deposited aluminum on one surface of a base material 14b formed of a plastic film such as a polyester tape. What formed 14a by adhesion | attachment, vapor deposition, etc. is used. Also,
An adhesive 14c can be applied to the base material surface opposite to the conductive foil 14a to be bonded and integrated with the plastic tape 18 forming the jacket 16. A pressure-sensitive adhesive, a hot-melt adhesive, or the like can be used as the adhesive 14c.
Various adhesives such as vinyl chloride, polyester, and ethylene vinyl acetate can be used as the hot-melt adhesive. When a hot-melt adhesive is used, it may be heated and fused after the plastic tape 18 is wound.

The metal foil tape 17 is wound by spiral winding or cigarette winding with the conductor foil 14a inside, and contacts the drain conductor 15 vertically attached to the lateral side surface of the insulated wire 11 over its entire length to be electrically connected. Is formed. When the metal foil tape 17 is wound with a cigarette as shown in FIG. 2, the side edges are partially wrapped and adhered with an adhesive to hold and fix the arrangement of the pair of insulated wires 11 and the drain conductor 15. When the adhesive 14c is applied to the base material surface of the metal foil tape 17 on the side opposite to the side where the conductor foil 14a is provided, the adhesive 14c can be used for bonding the wrap portion of the winding.

By bonding and integrating the jacket 16 and the shield conductor 14, the mechanical strength of the shield conductor 14 made of a metal foil having relatively low strength can be reinforced. In addition, when the terminal 16 is removed at the end of the shielded electric wire, the shield conductor 14 bonded and integrated when removing the outer cover 16 at the end is also used.
It can be peeled off integrally at the same time, and terminal treatment can be facilitated.

The plastic tape 1 forming the jacket 16
Various plastic tapes such as polyethylene terephthalate (PET) and polyvinyl chloride (PVC) can be used for 8. Instead of applying the adhesive 14 c to the surface of the shield conductor 14, an adhesive may be applied to the inner surface side of the plastic tape 18 forming the jacket 16 so as to be bonded and integrated with the shield conductor 14. . The plastic tape 18 for the jacket 16 is spirally wound around the outer periphery of the shield conductor 14. The winding direction is desirably opposite to the winding direction of the metal foil tape 17, but may be the same direction.

The jacket 16 can be formed by winding a plastic tape 18 around the shield conductor 14.
By changing the color of the plastic tape 18 to be wound, the shielded electric wire can be provided with an identification function. FIG. 4 shows a shielded wire that can be identified.
4A shows an example in which the color of the jacket 16 is changed, and FIG. 4B shows an example in which the jacket 16 is made of a transparent plastic tape 20 and a distinguishable color tape 19 is interposed therebetween. Show.

As shown in FIG. 4A, when the plastic tape 18 forming the jacket 16 is made to have a different color to have an identification function, the plastic tape 18 must be formed without increasing the outer diameter and the number of working steps. Can be. In the case of changing the color of the jacket, in the conventional extrusion coating molding, the setup work such as cleaning of the coating die for molding and color adjustment is difficult, but in the present invention, in order to change the color of the jacket 16, Simply changing the wrapping tape is very simple. At the extreme, it can be changed in the order of several meters during the process of forming the coating.

As shown in FIG. 4B, the outer cover 16 is formed of a transparent plastic tape 20 and a color tape 19 for identification is vertically attached between the shield conductor 14 and the outer cover 16 to perform an identification function. If it is provided, there is convenience in terms of material management and material cost. However, the outer diameter dimension, the number of work steps, and the like are increased by the amount of the color tape 19 interposed therebetween. However, since the tape is merely for color or display, it may be thin, and the transparent plastic tape 20 may be wound without being wound around the shield conductor 14. When winding, for example, width 1
It is sufficient to vertically attach a narrow tape of about mm, and the working time for this does not take much time.

As described above, instead of forming the jacket of the parallel two-core shielded wire by extrusion coating molding, the jacket is formed by winding a plastic tape so that the thickness of the jacket is 0.2 to 0.3 mm. Is smaller by one digit in the present invention.
It can be reduced to about 02 to 0.03 mm. In addition to forming the shield conductor with a metal foil tape and also forming the jacket with a plastic tape, it has become possible to reduce the diameter of the parallel two-core shielded wire.
Accordingly, when a large number of parallel two-core shielded wires are assembled into a cable, the cable diameter can be reduced, and when the cable diameters are the same, the number of shielded wires to be stored can be increased.

Further, since the coating die is not used unlike the extrusion coating molding, the arrangement of the drain conductor of the parallel two-core shielded wire is changed, the pair of insulated wires is twisted, and the arrangement and form of the wire structure are arbitrary. Therefore, it is not necessary to prepare a coating die, so that it is suitable for small-quantity multi-product production and can respond to sudden orders and delivery dates.

[0026]

As is apparent from the above description, according to the present invention, since the shield conductor and the jacket are formed by winding a metal foil tape and a plastic tape, respectively, the structure having a thin and small diameter can be obtained. It is possible to meet the demand for space saving and high-density mounting. In addition, since the shield conductor and the jacket are bonded and integrated,
In the terminal processing for electrical connection, the removal of the jacket and the removal of the shield conductor can be performed simultaneously and integrally, and the workability is improved. Furthermore, since a coating molding die is not used, it is possible to produce a large number of products in small quantities, and it is easy to obtain a parallel two-core shielded wire capable of color identification.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating an embodiment of the present invention.

FIG. 2 is a diagram illustrating another embodiment of the present invention.

FIG. 3 is an enlarged sectional view of the embodiment of the present invention.

FIG. 4 is a diagram showing an example of giving color discrimination in the embodiment of the present invention.

FIG. 5 is a view showing a conventional parallel two-core shielded electric wire.

FIG. 6 is a diagram in which a conventional parallel two-core shielded electric wire is formed into a cable.

FIG. 7 is a diagram illustrating a conventional parallel two-core shielded electric wire.

[Explanation of symbols]

11 ... insulated wire, 12 ... inner conductor, 13 ... insulator, 14
... shield conductor, 15 ... drain conductor, 16 ... jacket, 1
7 ... Metal foil tape, 18 ... Plastic tape, 19 ...
Color tape, 20 ... Transparent plastic tape.

Claims (4)

[Claims] At least one drain conductor is longitudinally attached to a pair of insulated wires arranged in parallel, and the insulated wire and the drain conductor are collectively wound with a metal foil tape to form a shield conductor. A parallel two-core shielded electric wire in which an outer peripheral portion of a shield conductor is covered with a jacket, wherein the outer sheath is formed by winding a plastic tape. 2. The parallel two-core shielded electric wire according to claim 1, wherein the metal foil tape forming the shield conductor and the plastic tape forming the jacket are bonded and integrated with an adhesive. 3. The plastic tape forming the outer cover is formed of a transparent tape, and a color tape is disposed between the shield conductor and the outer cover. Parallel two-core shielded wire. 4. The parallel two-core shielded electric wire according to claim 1, wherein the plastic tape forming the jacket is formed of polyethylene terephthalate (PET).