JPH10148739A - Aerial assembled outdoor optical cable - Google Patents

Abstract

PROBLEM TO BE SOLVED: To densely assemble aerial optical cables and to efficiently produce them by housing the aerial outdoor optical cables within an LAP pipe. SOLUTION: For example, twelve aerial optical cables 20 are housed within the LAP pipe 1 consisting of an aluminum layer 5 and a polyethylene layer 5, and the pipe 1 and an assembled optical cable supporting line 2 are integrated with an assembled optical cable sheath 3. The pipe 1 is provided with a hollow part of a size capable of loosely housing a necessary number of the cables 20 and forms a welding part 1a. Its thickness is small to a degree where strength has no problem but a hole is easily provided at its peripheral surface at the time of pulling out the cables 20. The line 2 uses the material of proper tensile strength for taking the stretching strength of the assembled optical cable. The sheath 3 integrates the pipe 1 and the line 2 by batch coating, protects them from mechanical external force at the time of laying and environment after laying, and is formed by extrude-coating proper resin material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an outdoor optical fiber cable in which optical overhead outdoor optical cables used for drawing in a general subscriber's house are assembled.

[0002]

2. Description of the Related Art At present, it is specifically studied to spread an optical fiber communication network to a subscriber's house such as a general home. In this case, as a method of wiring a communication optical fiber from a telephone station or the like to each subscriber's home, for example, a plurality of single-core overhead outdoor optical cables (hereinafter abbreviated as overhead optical cables) for drawing in the subscriber's home are assembled. A method has been proposed in which an optical cable for outdoor aerial assembly (hereinafter abbreviated as an aggregate optical cable) is installed on a utility pole, an aerial optical cable is pulled out from the aggregate optical cable as needed, and the optical fiber cable is pulled into a subscriber's house.

As such a collective optical cable, for example, a cable having a structure as shown in FIG. 8 has been proposed. The collective optical cable of this example has one overhead optical cable 40 and one
The back split pipe 6 is accommodated in the back split pipe 61.
1 is twisted around the tension member 64 by a required number, and a presser winding layer 65 and a sheath 66 are wound around these members.
Are sequentially formed. Tension member 64
Is a steel wire 62 on which PE (polyethylene) coating is applied. The holding roll layer 65 is formed by winding a nonwoven fabric tape or the like, and the sheath 66 is formed by extruding PE.

On the other hand, the aerial optical cable 40 housed in the cracked pipe 61 has a structure in which a cable main body 48 is spirally wound around a support wire 43. The support wire 43 is formed by coating a steel wire having an outer diameter of 1.2 mm with a PVC (polyvinyl chloride) sheath on the outer circumference. In addition, the cable body 48 is configured by disposing two steel wires having an outer diameter of 0.7 mm on both sides of a nylon-coated optical fiber core wire having an outer diameter of 0.9 mm, and integrating them with a PVC sheath. The collective optical cable thus configured is used by being installed on a utility pole or the like. Then, if necessary, a hole of an appropriate size is formed in the sheath 66, the presser winding layer 65, and the back crack pipe 61, and the overhead optical cable 4
0 can be pulled out, and this can be drawn into the subscriber's house or the like and wired.

[0005] However, in the collective optical cable having such a structure, there is a problem that the accommodation density of the overhead optical cables 40 is low, and if the number of the overhead optical cables 40 to be assembled is increased, the outer diameter of the collective optical cables becomes considerably large. Further, when manufacturing this collective optical cable, a step of inserting one overhead optical cable 40 into one back cracked pipe 61 and a step of twisting a plurality of back cracked pipes 61 around the tension member 64. Since the step of forming the presser winding layer 65 and the step of forming the sheath 66 are required, the number of steps is large and the manufacturing efficiency is low.

[0006]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a collective optical cable capable of assembling overhead optical cables at high density and efficiently manufacturing them.

[0007]

This problem can be solved by housing one or more overhead outdoor optical cables in a LAP pipe to form an overhead outdoor optical cable.
Also, the above-mentioned overhead outdoor optical cable can be manufactured by gradually bending the aluminum / polyethylene laminate in the longitudinal direction to form a pipe shape, and inserting one or more overhead outdoor optical cables therein. it can.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.
FIG. 1 is a sectional view showing an embodiment of the collective optical cable of the present invention. In the collective optical cable of the present embodiment, 12 overhead optical cables 20 are accommodated in the LAP pipe 1 and
The AP pipe 1 and the collective optical cable support line 2 are integrated by a collective optical cable sheath 3. LAP
Regarding the arrangement of the twelve overhead optical cables 20 in the pipe 1, each of the twelve overhead optical cables 20 may be separately and independently arranged, or the twelve overhead optical cables 20 may be bundled and integrated.

The LAP pipe 1 has a hollow portion large enough to accommodate a required number of overhead optical cables 20, and has a welded portion 1a formed on the peripheral surface along the length direction. The LAP pipe 1 has an aluminum layer (hereinafter referred to as Al layer).
It is described as a layer. 4), a PE layer 5 is provided, and these are integrated into a two-layer structure. In this embodiment, Al
The thickness of each of the layer 4 and the PE layer 5 is 0.2 mm, 0.0
5mm LAP with 21.5mm outer diameter and 21mm inner diameter
The pipe 1 is preferably used. This LAP pipe 1
The thickness of the LAP pipe is small enough that there is no problem in its strength and that a hole of an appropriate size can be easily formed in the peripheral surface of the LAP pipe 1 when the overhead optical cable 20 is pulled out. . The size of the hollow portion of the LAP pipe 1 is slightly larger than the size of the entire overhead optical cable 20 housed therein, and the overhead optical cable 20 is loosely housed.

The collective optical cable supporting wire 2 bears the tensile strength of the collective optical cable, and can be made of an appropriate tensile material. In the present embodiment, a steel stranded wire is suitably used. The collective optical cable sheath 3 is a LAP
The pipe 1 and the collective optical cable supporting wire 2 are collectively covered and integrated, and are protected from mechanical external force at the time of laying and the environment after the laying. Is preferably formed. In the present embodiment, it is formed by extrusion coating PE. The thickness of the collective optical cable sheath 3 is preferably thin in terms of reducing the diameter, weight, and economy of the collective optical cable, but if too thin, the reliability of the collective optical cable deteriorates. The collective optical cable of this embodiment has a thickness of 1.0 around the collective optical cable support line 2.
The LAP pipe 1 is provided with a PE coating having a thickness of 1.7 mm, and these are formed into a roughly gourd-shaped cross section connected by a sheath constriction 3a.

FIG. 2 is a sectional view of the overhead optical cable 20 used in this embodiment. This overhead optical cable 20
The first tension member 21, the second tension member 22a, the optical fiber 23 and the third tension member 22b are sequentially arranged on the same plane, and these are integrated by a sheath 24. . Here, arranging on the same plane means arranging the members in parallel so that the central axis of each member is located on the same plane. Also,
The size of the overhead optical cable 20 in a direction parallel to the plane in which the central axis of each member is located is referred to as a cable height, and the size of the overhead optical cable 20 in a direction perpendicular thereto is referred to as a cable width.

The aerial optical cable 20 has a cross-sectional shape in which a support line portion 20A having a substantially circular cross section is continuous via a neck 25 in the longitudinal direction of the cable portion 20B having a substantially elliptical cross section. . That is, at the position of the neck 25, the overhead optical cable 20 can be easily cut in the cable width direction, that is, the direction along the line BB 'in FIG. Then, by cutting the overhead optical cable 20 at this position, the first tension member 21 and the sheath 2 are cut.
4 and a cable portion 20B including the second and third tension members 22a and 22b, the optical fiber core 23, and the sheath 24. The sheath 24 on the circumference of the optical fiber core 23 is also provided with a weakening groove 26 having a cut in the cable width direction, so that the sheath 24 can be easily torn at the position of the weakening groove 26. ing.
By tearing the sheath 24 at this position, the optical fiber core wire 23 can be easily exposed.

The optical fiber 23 is not particularly limited, and single-core optical fibers having various structures can be suitably used. In this embodiment, the bare optical fiber is coated with an ultraviolet curable resin such as silicone to form an optical fiber, and the outer periphery thereof is coated with an ultraviolet curable resin. A core resin-coated core wire is preferably used.

Second and third tension members 22
a and 22b mainly connect the cable portion 20B to the support wire portion 20.
When the wiring is separated from A, the optical fiber core 23 bears the strength of the cable portion 20B so that the optical fiber core 23 is not broken. Also, when tapping the optical fiber 23,
The second and third tension members 22a, 22b
Used to pull the sheath 24 away from each other. In the present embodiment, a steel wire having an outer diameter of 0.4 mm is suitably used as the second and third tension members 22a and 22b in the present embodiment. The second tension member 22a is connected to the first tension member 21.
And on the same plane as the optical fiber core 23 and between the neck 25 and the optical fiber core 23. The third tension member 22b is provided at a position facing the second tension member 22a with the optical fiber 23 interposed therebetween. Second and third tension members 22
The distance between the center of a, 22b and the center of the optical fiber 23 can be changed as appropriate.

The first tension member 21 mainly bears the tensile strength when the overhead optical cable 20 is branched from the collective optical cable and wired overhead. In this embodiment, a steel wire having an outer diameter of 1.2 mm is suitably used.

The sheath 24 is connected to the first tension member 2
First, second and third tension members 22a, 22
b and the optical fiber 23 are integrated,
These are protected from mechanical external force during wiring and the environment after wiring. The sheath 24 is made of PVC or PE as a material.
Are preferably used, and are formed by extrusion coating.
Further, a lubricant is preferably added to the sheath 24. For example, erucylamide is preferably used as the lubricant,
The addition amount is preferably about 0.5 to 1%. It is preferable that the thickness of the sheath 24 is thinner because the diameter of the overhead optical cable 20 can be reduced. However, if the thickness is too thin, the first tension member 21 and the second tension member 22 are corroded,
The bending stiffness of the optical fiber 23 may be insufficient. Therefore, the cable portion 20B and the support wire portion 20
A so that these inconveniences do not occur even in a state where the optical fiber cable A is disconnected from the sheath A.
Is appropriately set.

The cross-sectional shape of the overhead optical cable 20 can be appropriately designed in consideration of the manufacturability and the like while ensuring the necessary thickness of the sheath 24. In the overhead optical cable 20 in this embodiment, the cross-sectional shape of the support wire portion 20A is a substantially circular shape with an outer diameter of 1.8 mm, and the cross-sectional shape of the cable portion 20B is a substantially elliptical shape with a short axis of 1.8 mm and a long axis of 2.6 mm. The thickness of the neck 25 in the cable width direction is formed to be 0.7 mm, the overall cable height is 6.1 mm, and the cable width is 1.8 mm. The depth of the weakening groove 26 provided in the vicinity of the optical fiber 23 is 0.2 mm.
Is formed.

In the overhead optical cable 20 having such a configuration, the first tension member 21, the second tension member 22a, the optical fiber 23, and the third tension member 22b are sequentially arranged on the same plane. It is obtained by applying an extrusion coating to form the sheath 24.

The collective optical cable of this embodiment can be manufactured as follows. FIG. 5 shows an example of an aluminum / polyethylene laminated tape (hereinafter abbreviated as Al / PE tape) used for the collective optical cable of the present embodiment. As this Al / PE tape,
0.2 mm thick Al layer 70 and 0.05 mm thick P
A width of 85 m formed by integrating two layers of the E layer 72
m and a thickness of 0.25 mm are suitably used.

FIG. 6 is a schematic view of a method for manufacturing a collective optical cable according to the present invention. First, a plurality of overhead optical cables 8
While gathering 0, the Al / PE tape 81 is introduced into the conical tubular former 82 at the same time. This Former 82
Is the overhead optical cable 80 and the Al / PE tape 8
The diameter is gradually reduced from the inlet part where 1 is introduced. In the former 82, the Al / PE tape 81 is gradually heated, and the Al shape is connected to the former 82 while being curved so as to surround the assembly of the overhead optical cables 80 with the Al layer inside. Is a tubular forming die 8
3 and formed into a pipe shape, and the seam along the longitudinal direction is heated and welded by a hot jet 85 to form a LAP pipe 84.

The LAP pipe 84 is introduced into the extruder head 88 together with the collective optical cable support wire 87 by the guide roller 86, and these are collectively extruded and covered with PE.
A collective optical cable sheath is formed to form a collective optical cable. At this time, the take-off device 89 is connected to the above-mentioned overhead optical cable 80, Al / PE tape 81, and collective optical cable support line 8.
7, and a collective optical cable manufactured by these components is pulled from upstream to downstream. The collective optical cable is finally wound by a winding device 90.

The forming die 83 includes the Al
FIG. 7A in which the / PE tape 81 is molded from the inside thereof,
A LAP pipe jig 91 as shown in FIG. The LAP pipe jig 91 includes a U-shaped retaining portion 92 and a tubular molded portion 96. The retaining portion 92 includes an upstream end portion 93 and two legs 94, 94 connected to the upstream end portion 93 and extending in parallel with the lengthwise direction. The upstream end portion 93 and the two legs The parts 94 are inserted into the molded part 96 except for parts thereof, and are integrated on the inner wall of the molded part 96. Further, the LAP pipe jig 91 is inserted into the forming die 83 from the upstream side while leaving the retaining portion 92 and a part of the forming portion 96. The outer wall of the forming part 96 and the forming die 8
3, a pipe-shaped gap corresponding to the LAP pipe 84 to be formed is formed.
Is locked by any locking means so that the LAP pipe jig 91 does not flow downstream.

At the time of manufacturing a collective optical cable, Al
/ PE tape 81 is inserted into the gap between the outer wall of the forming part 96 and the inner wall of the forming die 83 while being gradually curved in the former 82, and is formed into a pipe having a predetermined size to form a LAP.
At the same time as the pipe 84, the inlet 9
5, an overhead optical cable 80 is introduced therein, and the overhead optical cable 80 is stored in the LAP pipe 84. At this time, the molded portion 96 is made up of two legs 94, 94.
Therefore, there is no obstacle at the entrance 95 that prevents the introduction of the overhead optical cable 80. Therefore, even if the number of the optical fiber cables 80 is increased and the density of the collective optical cable is increased, the optical fiber cable can be manufactured without any problem.

The collective optical cable of this embodiment obtained in this manner is used by being laid on a telephone pole or the like. Then, if necessary, the collective optical cable sheath 3 and the LA
A hole of an appropriate size is formed in the P pipe 1, an overhead optical cable 20 is pulled out from the hole, and this can be drawn into a subscriber's house or the like and wired.

According to the collective optical cable of the present embodiment, since a plurality of overhead optical cables 20 are accommodated in one LAP pipe 1, the accommodation density of the overhead optical cables 20 is high, and the density of the aggregate optical cables is increased. A reduction in diameter can be achieved. The size of the hollow portion of the LAP pipe 1 is
Since the overhead optical cable 20 is slightly larger than the overall size of the overhead optical cable 20 and is loosely housed, the overhead optical cable can be easily pulled out. Further, since the LAP pipe 1 is heat-welded at the welding portion 1a, it is possible to prevent the peripheral surfaces of the LAP pipe 1 from partially overlapping. This LAP pipe 1
If the peripheral surfaces of the LAP pipes 1 partially overlap, the hollow portion of the LAP pipe 1 in which the aerial optical cable 20 is accommodated becomes narrower, which may make it difficult to pull out the aerial optical cable 20.

The method for manufacturing a collective optical cable according to the present embodiment includes forming an Al / PE tape 81 and forming an LAP pipe 84.
At the same time, it can be manufactured by a process of introducing a single-core overhead optical cable 80 into the LAP pipe 84 and a process of forming a collective optical cable sheath by extrusion coating, so that the number of manufacturing steps is reduced and the manufacturing efficiency is reduced. Can be significantly oriented. These steps can be performed continuously. Further, since the forming part 96 constituting the LAP pipe jig 91 is fixed by the two feet 94, 94, there is nothing obstructing the introduction of the overhead optical cable 80 at the entrance 95. For this reason, even if the density of the collective optical cable is increased, it can be manufactured without any problem.

The aerial optical cable 20 used in the present embodiment has a structure in which the support wire portion 20A and the cable portion 20B are integrated by the sheath 24, so that it is easy to manufacture and uses no bobbin. Can be wound. Further, at the neck 25 between the support wire 20A and the cable 20B, the cable 20B is easily separated from the support wire 20A as necessary,
Only the cable portion 20B can be used for wiring or the like.
Further, if a lubricant is added to the sheath 24, the pull-out property of the overhead optical cable 20 is improved. Therefore, one LA
Even when a plurality of overhead optical cables 20 are accommodated in the P pipe 1, the overhead optical cables 20 can be easily pulled out. Further, the second and third tension members 2
2a and 22b are respectively disposed at opposing positions with the optical fiber core 23 interposed therebetween, and the optical fiber core 23
Since the weakening groove 26 is provided in the sheath 24 on the circumference of the second member, the second and third tension members 22a and 22b are provided.
By pulling on the sheath 24, the sheath 24 can be easily torn. Therefore, when the optical fiber 23 is connected, the optical fiber 23 can be easily led out without damaging the optical fiber 23 or applying a large bending stress.

In this embodiment, one LAP pipe 1
Although two overhead optical cables 20 are accommodated, the LAP
The number of overhead optical cables 20 accommodated in the pipe 1 can be any number equal to or greater than one. Preferably 1 to 24
About a book. It is not always necessary to provide the collective optical cable support wire 2 as long as the collective optical cable can secure an appropriate strength. In the present embodiment, the collective optical cable is formed to have a substantially gourd-shaped cross section.
The shape of the collective optical cable is not limited to this and can be changed as appropriate. Further, in this embodiment, the first example of the aerial optical cable housed in the LAP pipe 1 has a structure shown in FIG. 2. Optical cables having various structures can be used as long as they can be wired overhead.

FIGS. 3 and 4 are sectional views respectively showing a second example and a third example of an overhead optical cable suitably used for the collective optical cable of the present invention. The overhead optical cable 10 shown in FIG. 3 includes a first tension member 11,
The second tension member 12 and the optical fiber core 13 are sequentially arranged on the same plane, and these are integrated by a sheath 14. This aerial optical cable 10 is significantly different from the aerial optical cable 20 of the first example in that the third tension member is not provided in the aerial optical cable 10, and
6 is the point attached vertically.

The aerial optical cable 10 has a cross section in a substantially gourd shape in which a support wire portion 10A having a substantially circular cross section and a cable portion 10B having a substantially circular cross section are connected via a neck portion 15. The neck portion 15 is provided with a weakening groove 15a in which a cut is made in the sheath 14 in the cable width direction, and the overhead optical cable 1 is located at the position of the weakening groove 15a.
0 can be easily cut in the cable width direction, that is, the direction along the line AA 'in FIG. By cutting the aerial optical cable 10 at this position, a support wire portion 10A composed of the first tension member 11 and the sheath 14, and a cable composed of the second tension member 12, the optical fiber core 13, and the sheath 14 are provided. The part 10B is separated. Further, a cord 16 is vertically attached to the optical fiber core 13, and a tear is formed in the sheath 14 by pulling the cord 16 so that the optical fiber 13 can be easily outputted therefrom. .

The optical fiber core 13, the first tension member 11, and the second tension member 12 are the same as the overhead optical cable 20 of the first example. In the overhead optical cable 10 of this example, the position where the second tension member 12 is provided is the first position.
Are on the same plane as the tension member 11 and the optical fiber
And can be changed as appropriate.

The sheath 14 is preferably formed by extrusion coating using PVC (polyvinyl chloride) or PE (polyethylene) as a material, similarly to the overhead optical cable 20 of the first example. Also preferably, the first
The same sliding material as the overhead optical cable 20 of the example is added. The thickness of the sheath 14 is set in the same manner as in the overhead optical cable 20 of the first example. The cross-sectional shape of the overhead optical cable 10 in this example is such that the cross-sectional shape of the support wire portion 10A is a substantially circular shape having an outer diameter of 1.8 mm, the cross-sectional shape of the cable portion 10B is a substantially circular shape having an outer diameter of 1.8 mm, and the neck portion 15 is formed. Is formed to have a thickness of 0.7 mm in the cable width direction, the overall cable height is 4.0 mm, and the cable width is 1.8 mm. The depth of the weakening groove 15a provided in the neck portion 15 is formed to be 0.3 mm. It is desirable to use a material having a small diameter and relatively excellent strength for the exit cord 16, and for example, an aramid fiber such as a poly-p-phenylene terephthalamide fiber (Kevlar: trademark) is suitably used.

In the overhead optical cable 10 having such a configuration, the first tension member 11, the second tension member 12, and the optical fiber core 13 are sequentially arranged on the same plane, and the sheath 14 is subjected to collective extrusion coating. Is obtained. The overhead optical cable 10 of the second example
Since the lead cord is vertically attached to the optical fiber core 13, when connecting the optical fiber core 13, a tear is formed in the sheath 14 by pulling the lead fiber 16, and the optical fiber core 13 can be easily taken out.

The overhead optical cable 30 shown in FIG.
Tension member 31 and second tension member 3
2a, the optical fiber core wire 33, and the third tension member 32b are sequentially arranged on the same plane, and these are integrated by a sheath. The difference between the overhead optical cable 30 of this example and the overhead optical cable 20 of the first example is that the second and third tension members 32 are different.
a and 32b are both made of a nonmetallic material.

The aerial optical cable 30 of this embodiment has a cross-sectional shape formed by connecting a support wire portion 30A having a substantially circular cross section to an end of a cable portion 30B having a substantially bow tie shape via a neck portion 35. ing. The neck portion 35 has a weakened groove 35 a formed by cutting a sheath 34 in a cable width direction.
Is provided. At the position of the weakening groove 35a, the overhead optical cable 30 is moved in the cable width direction, that is, C in FIG.
The support wire portion 30A including the first tension member 31 and the sheath 34 is easily cut in the direction along the line C '.
And second and third tension members 32a, 32b
And a cable portion 30B composed of the optical fiber core wire 33 and the sheath. The cable section 30B has a cross-sectional shape that is substantially bow-tie in which the cable width gradually decreases toward the central portion 35, and the optical fiber core 33 is disposed inside the central portion 36. The central portion 36 is provided with a weakening groove 36a in which a cut is made in the sheath 34 in the cable width direction. The sheath 34 is torn at the position of the weakening groove 36a, so that the optical fiber core wire 33 can be easily exposed. It has become.

The optical fiber core 33 and the first tension member 31 are the same as the overhead optical cable 20 of the first example. The second and third tension members 32a and 32b of the overhead optical cable 30 of this example are made of a non-metallic material, and are mainly used when the cable portion 30B is separated from the support wire portion 30A and wired. The cable portion 30B bears strength so as not to be disconnected. When the optical fiber core 33 is exposed, the second and third tension members 32a and 32b are used to pull the sheath 34 apart by pulling them away from each other. As the second and third tension members 32a and 32b, any suitable nonmetallic material can be used as long as the required strength is obtained. In this embodiment, FRP (glass fiber reinforced plastic) having an outer diameter of 0.7 mm is suitably used. The second and third tension members 32a,
The position where the 32b is provided is designed in the same manner as the overhead optical cable 20 of the first example.

The sheath 34 is preferably made of PVC (polyvinyl chloride) or PE (polyethylene) as a material, and is formed by extrusion coating, similarly to the overhead optical cable 20 of the first example. Also preferably, the first
The same sliding material as the overhead optical cable 20 of the example is added. The thickness of the sheath 34 is set in the same manner as in the overhead optical cable 20 of the first example. The cross-sectional shape of the aerial optical cable 30 of this example is such that the cross-sectional shape of the support wire portion 30A is substantially circular with an outer diameter of 1.8 mm, the cross-sectional shape of the cable portion 30B is substantially bow-tie-shaped, and the cable width of the central portion 36 thereof. Is 1.
6mm, 2.5m at the largest cable width
m. Further, the thickness of the neck portion 35 in the cable width direction is formed to be 0.7 mm, the overall cable height is 3.0 mm, and the cable width is 8.5 mm. The depth of the weakening groove 35a provided in the neck 35 is 0.2 m.
m, the depth of the weakening groove 36a formed in the central portion 36 of the cable portion 30B is formed to be 0.2 mm.

In the overhead optical cable 30 having such a configuration, the first tension member 31, the second tension member 32a, the optical fiber core wire 33, and the third tension member 32b are sequentially arranged on the same plane, It is obtained by applying an extrusion coating to form the sheath 34.

In the overhead optical cable 30 of this example, since the second and third tension members 32a and 32b are made of a non-metallic material, when the cable portion 30B is routed from the collective optical cable to the indoor wiring, the cable 30B is not connected. There is an advantage that there is no risk of lightning damage even if the ground is not taken. Therefore, for example, from the branch point of the collective optical cable to the termination cabinet of the subscriber's house, an overhead optical cable 30 is used, and from this point to the indoor outlet, the support line 30A is separated and only the cable 30B is used for wiring. In addition, the optical fiber cable 33 can be pulled in from the collective optical cable to the indoor outlet without connection, and the diameter of the indoor wiring can be reduced.

[0040]

According to the present invention, an optical cable for outdoor aerial assembly
One or more overhead outdoor optical cables are accommodated in a LAP pipe. Therefore, the accommodation density of the aerial outdoor optical cable is high, and the density and the diameter of the aerial collective outdoor optical cable can be increased. Also, the size of the hollow portion of the LAP pipe is slightly larger than the size of the entire aerial optical cable housed therein, and the aerial optical cable is loosely housed.
The overhead optical cable can be easily pulled out. Furthermore, LA
Since the P-pipe is heated and welded at the welding portion, it is possible to reliably prevent the peripheral surfaces of the LAP pipe from partially overlapping and the pull-out property of the overhead outdoor optical cable from being deteriorated. In addition, the above-mentioned optical cable for aerial assembly outdoor is formed by forming an aluminum / polyethylene laminate tape and forming a LAP.
It can be manufactured by a process of introducing a single-fiber overhead outdoor optical cable into the LAP pipe and a process of forming a collective optical cable sheath by extrusion coating at the same time as forming the pipe, thereby reducing the number of manufacturing steps and reducing the manufacturing efficiency. Can be greatly oriented. These steps can be performed continuously. In addition, L provided in the forming die
Since the molded part constituting the jig for the AP pipe is fixed by two feet, there is nothing obstructing the introduction of the overhead optical cable at the entrance. For this reason, even if the number of these overhead optical cables is increased to increase the density of the collective optical cable, the optical fiber cable can be manufactured without any problem.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of an optical cable for outdoor aerial assembly according to the present invention.

FIG. 2 is a cross-sectional view showing an aerial outdoor optical cable used for the aerial aggregate outdoor optical cable of FIG. 1;

FIG. 3 is a cross-sectional view showing another example of an aerial outdoor optical cable suitably used for an aerial aggregate outdoor optical cable of the present invention.

FIG. 4 is a cross-sectional view showing another example of the overhead outdoor optical cable suitably used for the overhead outdoor optical cable of the present invention.

FIG. 5 is a view showing an example of an aluminum / polyethylene laminated tape used for manufacturing an optical cable for outdoor aerial assembly according to the present invention.

FIG. 6 is an explanatory view showing an example of a method for manufacturing an optical cable for outdoor aerial assembly according to the present invention.

FIG. 7 is a view showing a LAP pipe jig used in the method for manufacturing an optical cable for an aerial assembly outdoor according to the present invention.

FIG. 8 is a cross-sectional view illustrating an example of a conventional overhead optical cable for outdoor use.

[Explanation of symbols]

1. LAP pipe, 10, 20, 30 ... Aerial outdoor optical cable

Continuing on the front page (72) Inventor Koichiro Watanabe 1440 Mitsusaki, Sakura-shi, Chiba Prefecture Inside Fujikura Sakura Factory (72) Inventor Shinichi Furukawa 3-2-19-1 Nishishinjuku, Shinjuku-ku, Tokyo Nippon Telegraph and Telephone Corporation (72) Inventor Kazuo Hokari Nippon Telegraph and Telephone Corporation

Claims (2)

[Claims] 1. An aerial assembly outdoor optical cable, wherein one or more aerial outdoor optical cables are accommodated in a LAP pipe. 2. An optical fiber cable for outdoor aerial assembly, wherein an aluminum / polyethylene laminated tape is gradually bent in the longitudinal direction to form a pipe shape, and one or more optical fiber outdoor optical cables are inserted therein. Production method.