JP2003346570A - Lan cable - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a LAN cable that can prevent deterioration in crosstalk characteristics. <P>SOLUTION: Four paired stranded wires 13 formed by covering an insulator 17 to a center conductor 15 are prepared. Then, the paired stranded wires gathered and arranged at the outer periphery of a mold inclusion 11a having grooves in which a plurality of grooves 23a are provided for integration. Furthermore, the integrated outer periphery is covered with coating 21 for forming the LAN cable 1, thus preventing the paired stranded wires 13 from moving to a section, and hence preventing the deterioration in the crosstalk characteristics. <P>COPYRIGHT: (C)2004,JPO

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a LAN cable in which twisted pair wires are collectively arranged, and more particularly to a LAN cable capable of improving crosstalk characteristics between twisted pair wires.

[0002]

2. Description of the Related Art Conventionally, as a LAN cable, FIG.
As shown in (a), a structure in which insulated wires 103 are collectively arranged around a circular interposition 101, and then an aluminum tape is vertically attached or spirally wound on the outer periphery thereof, and a jacket 105 is further covered on the outer periphery. LAN cables are known.

As shown in FIG. 7 (b), a twisted pair wire 102 formed by twisting two insulated wires 103 around a round interposition 101 is collectively arranged, and then an aluminum tape is vertically wound around its outer periphery. Attached or spirally wound, and a jacket 10
5 is known.

In FIG. 7B, the twisting pitch of the twisted pair wires 102 is set such that the difference between the twisting pitches of the twisted pair wires 102 is increased in advance so that crosstalk does not occur between the insulated wires 103. .

[0005]

As shown in FIGS. 7 (a) and 7 (b), a LAN cable composed of a round interposition 101 and an insulated wire 103, and a LAN cable composed of a round interposition 101 and a twisted pair wire 102 are used. LAN cable has a round-shaped round
This was effective in securing the distance between the insulated wires 103 (or the twisted pair wires 102) facing each other with the center at 1.

However, in the LAN cable, the twisting pitch of the insulated wire 103 is set at the cable designing stage, and the twisting rate is determined according to the twisting pitch. And from this twist rate, the insulated wire 1 per unit length
03, the conductor resistance and the attenuation of each insulated wire 103 are calculated. However, when the insulated wire 103 is twisted, for example, a bend is applied by a pass line and the insulated wire 1 is insulated.
When the feeding tension of the wire 03 changes, the arrangement of the insulated wires 103 is disturbed, and the calculated core length deviates from the calculated value, causing a problem that the standard may be broken.

[0007] In addition, the difference between the twisted pitches of the two insulated wires 109 is increased to improve the crosstalk characteristics. Of course, a short twisting pitch has a problem that the manufacturing efficiency is reduced because a twisting manufacturing time is longer than a long twisting pitch.

Further, a LAN cable used for a general LAN construction at present is 10BASE or 100BA.
Mainly SE. In the future, the shift to 100BASE or gigabit transmission will be planned with the expansion of the transmission capacity and the increase of the transmission speed.
An AN cable is desired.

[0009] The present invention has been made in view of the above,
An object of the present invention is to provide a LAN cable that can prevent deterioration of crosstalk characteristics.

[0010]

According to the first aspect of the present invention,
In order to solve the above-mentioned problems, an insulated wire formed by coating a central conductor with an insulator, a pair of twisted wires formed by twisting two insulated wires, and a locus drawn in the twist direction of the twisted pair wire A grooved interposer having a round cross section provided with a plurality of concave grooves in contact with a part thereof, and a twisted wire is collectively arranged in the grooved interposer and integrated, and then the outer periphery of the integral outer periphery is coated with an insulator. The gist shall consist of the subject and the subject.

According to a second aspect of the present invention, in order to solve the above problem, the outer diameter of the grooved interposition is substantially the same as the center diameter of the center gap formed by arranging the twisted pair wires. .
According to a third aspect of the present invention, in order to solve the above-described problem, the gist of the invention is that the twisted pair wire and the grooved interposition collectively arranged in the grooved interposition are integrally twisted. According to a fourth aspect of the present invention, in order to solve the above problem, after disposing the twisted pair wires in the concave grooves and integrating them, the outer periphery of the integrated wires is covered with a metal tape.

[0012]

Embodiments of the present invention will be described below with reference to the drawings.

(First Embodiment) FIG. 1 is a sectional view showing the configuration of a LAN cable 1 according to a first embodiment of the present invention. FIGS. 2A and 2B are cross-sectional views illustrating the configuration of grooved interventions 11a and 11b provided in the LAN cable 1. FIG.

In the LAN cable 1, four pairs of twisted wires 13 are collectively arranged around a grooved intervening portion 11a in which a plurality of concave grooves are provided on the outer periphery of an intervening member having a substantially round cross section. After both the interposition 11a and the twisted pair wire 13 are twisted in the same direction, the outer periphery thereof is covered with a jacket 21.

The grooved interposition 11a shown in FIG. 2 (a) has eight U-shaped grooves 23a formed in the longitudinal direction on the outer periphery of a cylindrical round interposition. In the present embodiment, the number of U-shaped grooves 23a is eight, but the number is not limited thereto and may be eight or more.

On the other hand, the grooved interposition 11b shown in FIG.
In the figure, eight V-shaped grooves 23b are formed in the longitudinal direction on the outer periphery of a cylindrical round interposition. Also in this case, the V-shaped groove 2
Although the number of 3b is eight, the number is not limited to this and may be eight or more.

The outer diameter of the grooved interpositions 11a and 11b is formed at the center of the circular shape when, for example, four twisted pair wires 13 having the same outer diameter are collectively arranged regardless of the shape of the groove. The diameter is substantially the same as the center diameter of the gap.

Referring back to FIG. 1, each twisted pair wire 13 is
5 is formed by coating an insulator 17 such as a resin. The twisted pair wire 13 is accommodated in the groove 23a of the grooved interposition 11a.

Next, with reference to FIG.
Will be described.

The outer diameter of the grooved interventions 11a and 11b is, for example, 0.9 mm, and the material thereof is preferably polyethylene PE or the like. The groove width of the grooves 23a and 23b provided on the outer periphery of the grooved interventions 11a and 11b is, for example, 0.2.
mm and the depth is 0.15 mm. Such a groove 2
Eight 3a and 23b are formed on the outer periphery of the interposition. When polyethylene PE or the like is used by foaming the grooved intervening portions 11a and 11b, the dielectric constant can be reduced and the flexibility is effectively improved.

Although not shown in FIG. 3, the center conductor 15
Has an outer diameter of, for example, 0.6 mm, and the outer diameter of an insulated wire 19 formed by coating the center conductor 15 with an insulator 17 is, for example, 1.4 mm. And this insulated wire 19
The outer diameter of the trajectory of the twisted pair wire is 2.8 m.
m.

The twisted pair wire 13 is inserted into the grooved interposition 11a.
LAN cable 1 formed by arranging four in the groove 23a
Has an outer diameter of, for example, 6.0 mm. At this time, the jacket 21
Is preferably a recyclable eco-friendly material made of polyvinyl chloride PVC or a polyolefin-based material, or an NHPE material. The cable weight of the LAN cable is, for example, 45 g / m.

The above-mentioned eco-friendly material is made of a non-halogen flame-retardant resin composition. In particular, a metal hydroxide is used in an amount of 20 to 5 parts by weight based on 100 parts by weight of a polyolefin resin.
0 parts by weight and less than 2 parts by weight and less than 10 parts by weight of a flame-retardant auxiliary, the specific gravity is 1.14 or less, the oxygen index is 24 or more and 34 or less.
It passes the 60 ° tilt combustion test specified in IS C3005. This eco-material is composed of a non-halogen flame-retardant resin composition. In particular, based on 100 parts by weight of a polyolefin resin, 20 parts by weight or more and less than 50 parts by weight of a metal hydroxide and 0.5 parts by weight of red phosphorus More than 2.5
It has a specific gravity of 1.14 or less, an oxygen index of 24 or more and 34 or less, and is defined in JIS C3005 when used as a coating material. Those that pass the 60 ° tilt combustion test may be used.

The center conductor 15 is preferably made of silver-plated copper wire or tin-plated copper wire. The use of a silver-plated copper wire is effective in improving the signal attenuation on the high frequency side. Further, if the material of the insulator 17 is foamed polyethylene PE or the like, it is effective in lowering the dielectric constant, and is also effective in improving flexibility.

Although not shown in FIG. 3, the metal tape 19 is preferably an aluminum tape or a copper tape having a thickness of, for example, 0.06 mm and a width of 12 mm. Or by applying an adhesive, the adhesion between the jacket 21 and the insulator 17 may be improved.

Next, referring to FIG.
The operation and effect of will be described.

First, two insulated wires 19 formed by covering the center conductor 15 with the insulator 17 are twisted to form a pair of twisted wires 1.
3 is formed, and four of them are prepared. Next, the four twisted wires 13 are collectively arranged around the grooved interposition 11a, and the grooved interposition 11a and the twisted pair wire 13 are twisted together in the same direction. LA
The N cable 1 is formed.

Incidentally, although not shown in FIG.
After twisting both the wire 1a and the twisted pair wire 13 in the same direction, a metal tape may be longitudinally or spirally wound around the outer periphery. As a result, the shielding effect of the twisted pair wire 13 can be improved, which is effective in blocking external electric noise.

As a result, by providing the grooved interposition 11a, the twisted pair wire 13 can be arranged in the U-shaped groove 23a provided on the outer periphery of the grooved interposition 11a.
It is possible to prevent the twisted pair wire 13 from moving in a direction parallel to the cross section.

Further, by providing a plurality of U-shaped grooves 23a on the outer periphery of the grooved interposition 11a, resistance to movement of the twisted pair wire 13 in the circumferential direction is obtained. The distance can be kept constant.

Therefore, since the parallel movement with respect to the cross section is reduced, the distance between the paired twisted wires 13 is kept constant, and the deterioration of the crosstalk between the twisted paired wires 13 can be reduced.

Further, by twisting both the grooved interposition 11a and the twisted pair wire 13 in the same direction, a centripetal force is generated in the center direction of the grooved interposition 11a, and the twisted pair wire 13 and the paired twisted wire 11 are twisted.
Since the adhesive force increases between a, the arrangement of the twisted pair wires 13 is stabilized. Thereby, deterioration of crosstalk between the twisted pair wires 13 can be reduced.

Furthermore, by twisting the grooved interposition 11a and the twisted pair wire 13 together in the same direction, the LAN cable 1
Since the flexibility of itself is improved, it is easy to bend, and it is possible to flexibly cope with the environmental condition at the time of laying.

Further, the outer diameter of the grooved interposition 11a is set to 4
The outer diameter of the LAN cable 1 can be minimized by making the center diameter of the gap formed at the center when the twisted pair wires 13 having the same outer diameter are collectively arranged in a circle have the same diameter. Therefore, it is possible to prevent the cable from deviating from the cable standard.

Further, by providing the grooved interposition 11a,
Since the distance between the twisted pair wires 13 can be stably maintained, deterioration of the crosstalk characteristics can be prevented.
As a result, in order to reduce the crosstalk, the difference in the twisting pitch has been increased until now. However, this is no longer necessary, and the twisted pair wire 13 can be manufactured with substantially the same twisting pitch. Speed is improved, and production costs can be reduced.

Although the present embodiment has been described with reference to the grooved interposition 11a having the U-shaped groove 23a, the V-shaped groove 23a is replaced with the grooved interposition 11a.
The same effect as in the above embodiment can be obtained even if the grooved interposition 11b having b is arranged.

(Second Embodiment) FIG. 4 is a sectional view showing a configuration of a LAN cable 3 according to a second embodiment of the present invention. The feature is that, in the LAN cable 1 of FIG.
It is to provide.

In the LAN cable 3, four twisted pair wires 13 are gathered and arranged around a star-shaped interposition 11c having a number of V-shaped grooves 23b on the outer periphery of the interposition having a substantially round cross section. After the star-shaped interposition 11c and the twisted pair wire 13 are both twisted in the same direction, the outer periphery thereof is covered with a jacket 21.

As shown in FIG. 5, the star-shaped interposition 11c has a large number of V-shaped grooves 23b formed continuously on the outer periphery of a cylindrical round interposition. Further, the outer diameter of the cross section of the grooved interposition 11c is, for example, 4 having the same outer diameter regardless of the shape of the groove.
When the paired twisted wires 13 are collectively arranged in a circle, the diameter is substantially the same as the center diameter of a gap formed at the center of the circle.

Next, with reference to FIG.
The specifications of the LAN cable 3 having the above will be described.

The outer diameter of the star-shaped interposition 11c is, for example, 0.9 m.
m, and the material is preferably polyethylene PE or the like. The depth of the groove 23b formed on the outer surface of the star-shaped interposition 11c is 0.2 mm. Such a groove 2
Eighteen 3b are formed on the outer periphery of the interposition. Star-shaped intervention 1
When foamed polyethylene PE or the like is used as the material 1c, the dielectric constant can be reduced and the flexibility is effectively improved.

Although not shown in FIG. 3, the center conductor 15
Has an outer diameter of, for example, 0.6 mm, and the outer diameter of an insulated wire 19 formed by coating the center conductor 15 with an insulator 17 is, for example, 1.4 mm. And this insulated wire 19
Is 2.8 mm.

The outer diameter of the LAN cable 3 formed by arranging four such twisted pair wires 13 around the star-shaped interposition 11c is, for example, 6.0 mm. At this time, the material of the jacket 21 is preferably a recyclable eco-friendly material made of polyvinyl chloride PVC or a polyolefin-based material, or an NHPE material. The cable weight of the LAN cable 3 is, for example, 4
It becomes 5 g / m.

On the other hand, it is preferable to use a silver-plated copper wire or a tin-plated copper wire for the center conductor 15. The use of a silver-plated copper wire is effective in improving the signal attenuation on the high frequency side. The material of the insulator 17 is foamed polyethylene PE
Equally effective for lowering the dielectric constant and improving the flexibility.

Incidentally, although not shown in FIG.
After twisting c and the twisted pair wire 13 together in the same direction,
A metal tape may be wound vertically or spirally around this outer periphery. As a result, the shielding effect of the twisted pair wire 13 can be improved, which is effective in blocking external electric noise.

Next, referring to FIG.
The operation and effect of will be described.

First, two insulated wires 19 formed by covering the central conductor 15 with the insulator 17 are twisted to form a paired wire 1.
3 is formed, and four of them are prepared. Next, four twisted pair wires 13 are arranged around the star-shaped interposition 11c, and the star-shaped interposition 11c and the twisted pair wire 13 are twisted together in the same direction. To form the LAN cable 3.

As a result, by providing the star-shaped interposition 11c, the V-shaped groove 2 provided on the outer periphery of the star-shaped interposition 11c is provided.
Since the twisted pair wire 13 can be arranged at 3b, it is possible to prevent the twisted pair wire 13 from moving in a direction parallel to the cross section.

Also, by providing a large number of V-shaped grooves 23b on the outer periphery of the star-shaped interposition 11c, resistance to movement of the twisted pair wire 13 in the circumferential direction is obtained. Can be kept constant.

Therefore, since the parallel movement with respect to the cross section is reduced, the distance between pairs of the twisted pair wires 13 is kept constant, so that the deterioration of crosstalk between the twisted pair wires 13 can be reduced.

Further, by twisting both the star-shaped interposition 11c and the twisted pair wire 13 in the same direction, a centripetal force is generated in the center direction of the star-shaped interposition 11c, and the star-shaped interposition wire 11c and the star-shaped interposition 11c are interposed. Since the adhesion is increased, the arrangement of the twisted pair wires 13 is further stabilized, and the arrangement disorder can be reduced. That is, deterioration of crosstalk between the twisted pair wires 13 can be reduced.

Further, by twisting both the star-shaped interposition 11c and the twisted pair wire 13 in the same direction, the flexibility of the LAN cable 3 itself becomes good, so that the LAN cable 3 becomes easy to bend, and the LAN cable 3 can be easily bent according to the environmental condition at the time of laying. Can respond flexibly.

Further, by making the cross-sectional area of the star-shaped interposition 11c substantially equal to the central void area formed by arranging the four twisted pair wires 13 in a donut shape, the LAN cable 3
Since the outside diameter of the cable can be minimized, it is possible to prevent the cable from deviating from the cable standard.

Furthermore, since the distance between the twisted pair wires 13 can be stably maintained, the necessity of intentionally changing the twisting pitch and twisting is eliminated, so that the twisting pitch is set to be longer. Since the production linear velocity can be increased, it is possible to contribute to a reduction in production cost.

[0055]

According to the first aspect of the present invention, the center of the rounded interposition having a plurality of concave grooves on the outer periphery of the round interposition is mainly determined.
By arranging the twisted pair wires, the frictional resistance increases due to the groove provided in the grooved interposition, so that the twisted pair wires can be prevented from moving in parallel to the cross section, preventing alignment disorder and crosstalk Deterioration of characteristics can be reduced. Also,
Since the difference in the twist pitch can be reduced due to the prevention of the disorder of the arrangement, the twisting production speed of the twisted pair wire can be increased, and the production cost can be reduced.

According to the second aspect of the present invention, the outer diameter of the grooved interposition is substantially the same as the center diameter of the circular center gap formed by arranging the twisted pair wires, so that the LAN cable can be used. Since the outer diameter of the cable can be minimized, the outer diameter of the cable can be prevented from deviating from the standard.

According to the third aspect of the present invention, the twisted pair and the paired twisted wire are twisted together after the twisted pair is collectively arranged in the grooved interposition. Since the adhesion with the interposition can be improved, the arrangement of the twisted pair wires is further stabilized, and as a result, the deterioration of the crosstalk characteristic can be further reduced.

According to the fourth aspect of the present invention, after the twisted pair wires are arranged in the groove and integrated, the outer periphery of the integrated wire is covered with a metal tape, so that the twisted pair wires can be electrically connected to the outside. Since it is less likely to be guided, the electrical characteristics of the LAN cable can be improved.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a configuration of a LAN cable 1 according to a first embodiment of the present invention.

FIG. 2 shows a grooved interposition 11a having a U-shaped groove 23a.
(A) of FIG. 7 and a cross-sectional view (b) of a grooved intervention 11b having a V-shaped groove 23b.

FIG. 3 is a table showing cable specifications of the LAN cable 1 according to the first embodiment of the present invention.

FIG. 4 is a sectional view showing a configuration of a LAN cable 3 according to a second embodiment of the present invention.

FIG. 5 shows a star-shaped intervention 11 according to a second embodiment of the present invention.
It is sectional drawing of c.

FIG. 6 is a table showing cable specifications of a LAN cable 3 according to a second embodiment of the present invention.

FIG. 7A is a cross-sectional view of a conventional LAN cable including a round interposition 101 and a twisted pair wire 103, and FIG. 7A is a cross-sectional view of a LAN cable including a conventional round interposition 101 and a twisted pair wire 102. FIG.

[Explanation of symbols]

1,3 LAN cable 11a, 11b Groove type interposition 11c Star-shaped intervention 13,33 twisted pair 15 center conductor 17 Insulator 21 Jacket 23a, b groove

   ────────────────────────────────────────────────── ─── Continuation of front page    (72) Inventor Keiji Ohashi             Fujikura Co., Ltd.             Sakura Office

Claims (4)

[Claims] 1. An insulated wire formed by covering a central conductor with an insulator; a pair of twisted wires formed by twisting two insulated wires; and a locus drawn in a twist direction of the twisted pair wire. A grooved interposition having a round cross-section having a plurality of concave grooves in contact with a part thereof, and after the twisted pair wires are collectively arranged in the grooved interposition and integrated, the outer periphery of the integral is covered with an insulator. A LAN cable, comprising: 2. The LAN cable according to claim 1, wherein an outer diameter of the grooved interposition is substantially the same as a center diameter of a center gap formed by arranging the twisted pair wires. 3. The LAN cable according to claim 1, wherein the twisted pair wires and the grooved interposer collectively arranged in the grooved interposition are integrally twisted. 4. The method according to claim 1, wherein after the twisted pair wires are arranged in the concave groove and integrated, a metal tape is coated on an outer periphery of the integrated wire. LAN cable.