JP2001251746A - Stringing method for drop cable - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a drop cable stringing method which does not have problems such as waste of cables, deterioration of the loss characteristics of optical fibers, inability to apply to existing DV wires, and so on. SOLUTION: An optical drop cable 7 is bundled into one along together with an existing or new DV wire (lead-in vinyl electric wire) 4, and led and dropped into a house 10 by the following procedures from an overhead wiring network, in which distribution lines 1 and wiring system optical cables 2 are strung side by side. A string is inserted into the spiral of a spiral pipe 6 formed into a spiral. The existing or a new DV wire 4 is passed through the spiral of the spiral pipe 6 containing a string, and the spiral pipe 6 is arranged to extend approximately over the whole length of the DV wire 4. A spiral pipe 6 and a string are added as occasion demands. On one end of the spiral pipe 6, the optical drop cable 7 is connected to a string 5, and the string is drawn from the opposite side and the drop cable 7 is drawn into the spiral of the spiral pipe 6. The utility pole 3 side end of the drop cable 7, penetrating the spiral of the spiral pipe 6, is connected to a wiring system optical cable 2 with a closure 15, and its house 10 side end is connected to an outdoor optical junction box 11 on the house.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to, for example, a case where a cable is dropped from a communication optical cable to a house (consumer) in an overhead distribution network in which a communication optical cable is laid in parallel on an overhead distribution network. The present invention relates to an applied drop cable laying method.

[0002]

2. Description of the Related Art In recent years, the use of optical fibers in public communication networks has been promoted, and it has been aimed at realizing an optical communication network by arranging communication optical cables to individual homes. It is laid in parallel with the electric wire network. Accordingly, as a drop line to each house, a lead-in vinyl electric wire (hereinafter referred to as DV line) and an optical drop cable for communication are laid together. Due to problems, installation space, etc., it is required to bundle these cables. As a technology of uniting to meet this demand, D
A method of laying a collective cable in which a V line and an optical drop cable are bundled (assembled) has been considered.

[0003]

However, according to the method using the bundled collective cable, since the connection positions of the DV line and the optical drop cable are different, one of the cables becomes useless. In the state where the drop cable is assembled, the cross section is not regular and has a rather irregular structure, so that the optical fiber is liable to bend irregularly in the drum wound state, and there is a concern about the loss characteristics of the optical fiber. There is a problem that it can be applied only to the case where both the cable and the optical drop cable are newly installed.

[0004] The present invention has been made in view of the above circumstances, and as described above, a drop cable that does not cause the problems of wasting the cable, concerns about the loss characteristics of the optical fiber, and cannot be applied to existing DV wires. It is an object of the present invention to provide a method of laying.

[0005]

A drop cable laying method according to the present invention is characterized in that when dropping a cable from an overhead distribution network, the drop is performed in the following procedure. (1) A helical pipe having both ends passed through a helical pipe having both ends connected to a drop point of an aerial wiring network and a mounting point on the house side (pass the helical inner space of the helical pipe) T), disposing the helical pipe with the cord over substantially the entire length from the attachment point of the filament to the drop-off point. (2) A drop cable is connected to a string inside the spiral pipe at one end side. (3) Pulling the other end of the cord, pulling the drop cable into the spiral pipe, and penetrating the other end. (4) Connect both ends of the drop cable to the overhead wiring main line and the outdoor connection box on the house side, respectively.

A second aspect of the present invention provides the following when a cable is dropped from the communication optical cable wiring system in an overhead wiring network in which at least two wiring systems of a distribution line system and a communication optical cable wiring system are laid in parallel. It is characterized in that a debit is performed in a procedure. (1) A spiral pipe passing through a string is passed through an insulated electric wire having both ends connected to a drop point of an aerial wiring network and an outdoor power box of a house, and the spiral pipe with a string is inserted therein.
The insulated insulated wires are arranged over substantially the entire length from the outdoor power supply box to the drop point. (2) An optical drop cable is connected to a string inside the spiral pipe at one end side. (3) Pull the other end of the cord to pull the optical drop cable into the spiral pipe and penetrate the other end. (4) Both ends of the optical drop cable are connected to a communication optical cable distribution system main line and an outdoor optical connection box on the house side, respectively. .

[0007]

FIG. 1 is a block diagram showing an embodiment of the present invention.
This will be described with reference to FIGS. In this embodiment, as shown in FIG. 2, a lead-in vinyl from a distribution line system (distribution line 1) is used in an overhead distribution network in which two distribution systems of a distribution line system and a communication optical cable distribution system are laid in parallel. Electric wires (hereinafter,
4) is a utility pole 3 that has already been withdrawn,
This is a method for laying a drop cable when a cable is dropped from a communication optical cable wiring system (wiring system optical cable 2).

In the present invention, as shown in FIGS. 1 (a) and 1 (b), a cord 5 is provided inside a spiral pipe 6 formed in a spiral shape.
Through. Regarding the shape of the spiral pipe 6,
It is desirable that the inner diameter is sufficiently larger than the outer diameter of the optical drop cable 7 described later and the inner surface is smooth. Specifically, it has an inner diameter that is 1.1 times or more the outer diameter of the optical drop cable, and is made of a plastic such as polyethylene, nylon, polybutylene terephthalate (PBT) or PVC, or a metallic material such as aluminum or stainless steel. It is desirable that
In addition, as for the cord 5 in the spiral pipe 6, it is necessary to pull the optical drop cable 7, so that the breaking strength is 5 kg.
It is desirable to have one or more. Note that the string 5 is preferably passed through the pipe at a factory in advance when the spiral pipe 6 is manufactured.

The helical pipe 6 with a cord is prepared near the telephone pole 3 where the cable is to be dropped off as shown in FIG. The illustrated example is a case where a plurality of spiral pipes 6 are used as necessary, and they are connected and used as described later. The length of each helical pipe 6 is set to an appropriate length in consideration of the workability of pulling the cable, the transportability, etc., but the final part to be connected is cut and shortened according to the required total length. Good. Reference numeral 10 denotes a house from which the optical drop cable 7 is to be dropped, reference numeral 11 denotes an outdoor optical connection box for the optical cable, and reference numeral 12 denotes an outdoor power supply box for the DV line 4.

(1) First, as shown in FIG. 3, the above-described helical pipe 6 with a cord is passed through the existing DV line 4 (through the spiral inner space of the helical pipe 6), and As shown in FIG. 4, the helical pipe 6 is disposed over substantially the entire length of the DV line 4 from the outdoor power supply box 12 to the drop point (upper part of the utility pole 3). In this case, the spiral pipe 6
Has a spiral shape, and even if both ends of the DV line 4 are fixed and there is no open end, when the DV line 4 is rotated around the DV line 4 so as to enter the center of the spiral, FIG. DV like
Line 4 can be passed. In that case, first DV line 4
The threaded spiral pipe 6 and the subsequent threaded spiral pipe 6 are connected with the string 5 first, and then the spiral pipe 6 itself is connected with the sleeve 13 or the like. In addition, the spiral pipe 6 with a cord is usually passed through the DV line 4 from the house 10 side, but may be from the opposite pole 3 side. (2) Next, an optical drop cable 7 is connected to the string 5 inside the cord-containing spiral pipe 6 on the utility pole 3 side. FIG. 5 shows a state immediately before connection. (3) Next, the end of the cord 5 exposed on the house side is pulled, and the optical drop cable 7 is drawn into the spiral pipe 6 (see FIG. 6), and penetrated to the house 10 side. (4) Next, the end of the optical drop cable 7 penetrating the spiral pipe 6 on the utility pole 3 side is connected to the wiring optical cable 2.
The cable 15 is connected to the wiring optical cable 2 by a closure 15 attached thereto, and the end on the house 10 side is connected to the outdoor optical connection box 11 on the house side. At this time, the vicinity of the end of the optical drop cable 7 on the utility pole 3 side may be fixed to the DV wire 4 with a tape or the like. Thus, the dropping of the optical drop cable 7 to the house 10 is completed. FIG. 7 shows a state where the withdrawal is completed.

In the above-described embodiment, the optical drop cable is bundled with the existing DV line 4 and dropped. When the DV line 4 is newly provided, the DV line 4 is dropped in advance. . That is, both ends of the newly installed DV line 4 are connected to the utility pole 3 side and the house 10 side. However, when the DV line 4 is newly installed, both ends of the DV line 4 may be connected to the utility pole 3 side and the house 10 side after the helical pipe 6 with a cord is passed through the DV line 4 on the ground. When there is no existing DV line 4 and no new DV line 4 is provided, a messenger wire may be used instead of the DV line 4 as a striated body through which the spiral pipe 6 passes. In this case, the messenger wire functions simply as a support line.

When only the DV line is to be withdrawn,
DV as a drop cable on the cord 5 of the spiral pipe 6
Connect the wires and use messenger wires as the striatum. That is, the optical drop cable 7 in FIGS. 1 to 7 is replaced with a DV wire, and the DV wire 4 is replaced with a messenger wire.

FIGS. 8A, 8B and 8C show examples of the structure of the optical drop cable 7. FIG. The optical drop cable 7 of (a) has a structure in which a tension member 7b made of a steel wire, FRP, or the like is arranged on both sides of a central optical fiber core wire 7a and a resin coating 7c is applied. Are used as the above-mentioned optical element of a collective drop cable in which a plurality of optical elements (optical fiber cords as a structure) are collected around. (B)
The optical drop cable 7 has a circular resin coating 7c. The optical drop cable 7 of (c) has a structure in which the periphery of the optical fiber core wire 7a is surrounded by a tensile strength fiber 7d, and a sheath 7e is provided around the circumference. However, the optical drop cable 7 to be used is not limited to this structure and is optional.

An example of the structure of the DV line 4 is shown in FIG.
It is shown in (b). (A) is a 2-stranded DV wire, (B) is 3
It is a co-twisted DV wire having a structure in which two (in the case of (a)) or three (in the case of (b)) vinyl-coated electric wires 4c in which the outside of the conductor 4a is covered with a vinyl insulator 4b are twisted. is there.

In the above drop cable laying method, the optical drop cable 7 and the DV wire 4 are not bundled in a factory in advance to form a collective cable, but are integrated at the drop-down work site with the respective drop-down lengths. Therefore, even if the connection positions of the DV wire 4 and the optical drop cable 7 are different, there is no problem that one of the cables is wasted. Also, unlike the conventional bundled cable, the optical drop cable 7 does not have an irregular structure in which irregular bending occurs in a drum-wound state, so that the problem of the optical fiber loss characteristics does not occur. Also, since only one of the DV wire and the optical drop cable can be laid, the present invention can be applied even when one of them is already installed.

Even if it is not necessary to drop the optical cable now, if only the helical pipe 6 with a cord is bundled with the existing or newly installed DV wire 4 in advance, the demand for the optical cable dropping is newly generated. , Its spiral pipe 6
The optical drop cable 7 bundled with the DV wire 4 can be easily pulled down by passing the optical drop cable 7 through the optical drop cable 7.

The optical drop cable may be laid at a point where the telephone pole is dropped (usually a telephone pole as in the embodiment) from the outdoor optical connection box 11 of the house 10 as in the embodiment.
However, the present invention can also be applied to the case where debits are made between telephone poles, and further from the mounting point of the house 10 after the telephone pole is drawn down to the house 10 to another house. It is also possible to apply in between. Also,
In the illustrated embodiment, the filament that passes through the spiral pipe 6 is an existing or newly installed DV wire (lead-in vinyl electric wire) 4 for electric power, and this case is generally used. For example, a metal drop cable (a drop cable for a communication wire) or the above-described messenger wire may be used. When the striatum is a messenger wire, it functions as a simple support line. As the drop cable to be pulled down through the helical pipe, a metal drop cable, a coaxial cable, a power cable or the like can be used in addition to the optical drop cable 7 as in the embodiment.

[0018]

According to the drop cable laying method of the present invention, after the spiral pipe with the string is passed through the striatum to be bundled, the drop cable is connected to the string.
By pulling the string and pulling the drop cable into the spiral pipe, the drop cable can be bundled into a striated body, so that it can be easily bundled at the construction site.

Also, for example, a lead-in vinyl electric wire (DV wire)
As for the case where the optical drop cable 7 and the optical drop cable 7 are drawn down, the optical drop cable 7 and the DV wire 4 are not bundled at the factory in advance to form a collective cable, but are passed through the helical pipe 6 at the pull-down construction site. It is integrated with each withdrawal length,
Even if the connection positions of the DV wire 4 and the optical drop cable 7 are different from each other, there is no problem that one of the cables becomes useless. Since there is no irregular structure in which irregular bending occurs in the wound state, the problem of the loss characteristic of the optical fiber does not occur.
Since only one of the wire 4 and the optical drop cable 7 can be laid, an effect is obtained that the present invention can be applied even when one of the wires 4 and the optical drop cable 7 is already installed.

Further, only the spiral pipe 6 is connected to the DV line 4 in advance.
When the demand for the optical cable dropping is newly generated, the optical drop cable 7 is passed through the helical pipe 6 to drop the optical drop cable 7 bundled with the DV wire 4. Can be easily performed.

[Brief description of the drawings]

FIG. 1 shows a helical pipe with a cord used in a method for laying a drop cable according to an embodiment of the present invention.
2 is a side view, and FIG.

FIG. 2 is a diagram illustrating a method of laying a drop cable according to an embodiment of the present invention, and is an explanatory diagram of a laying start stage.

FIG. 3 is a view for explaining the work following the step shown in FIG. 2 of the method of laying the drop cable, and is a drawing vinyl electric wire (DV).
It is a figure explaining the point of letting a spiral pipe pass through (line).

FIG. 4 is a diagram illustrating a stage in which the operation of FIG. 2 is completed in the drop cable laying method.

FIG. 5 is a view for explaining the operation at the stage following FIG. 4 and is a view showing a state immediately before connecting an optical drop cable to a string inside a spiral pipe.

FIG. 6 is a diagram illustrating an operation subsequent to FIG. 5 and illustrating an operation of pulling a string and pulling an optical drop cable into a spiral pipe.

FIG. 7 is a diagram illustrating a state in which both ends of the optical drop cable are connected after the operation of FIG. 5 is completed, and the dropping of the optical drop cable is completed.

FIG. 8 shows an example of the structure of an optical drop cable in the method of laying the drop cable, wherein (a),
(B) and (c) are cross-sectional views of optical drop cables having different structures.

FIG. 9 shows a DV in the method of laying the drop cable.
It is sectional drawing which shows an example of a wire (vinyl insulated wire for draw-in), (a) is a case of 2 twists, (b) is a case of 3 twists.

[Description of Signs] 1 Distribution system (distribution line) 2 Communication optical cable distribution system (wiring system optical cable) 3 Utility pole 4 DV line (insulation wire for drop-in: vinyl wire for drop-in) (filament) 5 String 6 Spiral Pipe 7 Optical drop cable (drop cable) 7a Optical fiber core wire 7b Tension member 7c Resin coating 10 House 11 Outdoor optical connection box 12 Outdoor power supply box

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Masahiro Kusakari 1440, Misaki, Sakura City, Chiba Prefecture Inside Fujikura Sakura Office (72) Inventor Suehiro Miyamoto 1440, Misaki, Sakura City, Chiba Prefecture Inside Fujikura Sakura Office F Term (reference) 2H038 CA63 5G357 DA06 DB02 DC20 DD01 DD05 DD13 DG10 5G367 DA03 DB17 DC01 GA03 GA04 GB03 GC02 GC06

Claims (2)

[Claims] 1. A method for laying a drop cable, comprising: when dropping a cable from an overhead wiring network, the dropping is performed in the following procedure. (1) By passing a helical pipe with a string through the inside of a striated body having both ends connected to the drop point of the aerial wiring network and the mounting point on the house side, The wire is disposed over substantially the entire length from the attachment point to the drop-off point. (2) A drop cable is connected to a string inside the spiral pipe at one end side. (3) Pulling the other end of the cord, pulling the drop cable into the spiral pipe, and penetrating the other end. (4) Connect both ends of the drop cable to the overhead wiring main line and the outdoor connection box on the house side, respectively. 2. When a cable is drawn down from the communication optical cable wiring system in an overhead wiring network in which at least two wiring systems of a distribution line system and a communication optical cable wiring system are laid in parallel, the following procedure is used. A method for laying a drop cable, comprising: (1) A spiral pipe passing through a string is passed through an insulated electric wire having both ends connected to a drop point of an aerial wiring network and an outdoor power box of a house, and the spiral pipe with a string is inserted therein.
The insulated insulated wires are arranged over substantially the entire length from the outdoor power supply box to the drop point. (2) An optical drop cable is connected to a string inside the spiral pipe at one end side. (3) Pull the other end of the cord to pull the optical drop cable into the spiral pipe and penetrate the other end. (4) Both ends of the optical drop cable are connected to a communication optical cable distribution system main line and an outdoor optical connection box on the house side, respectively.