JP2002095121A - Method for installing optical fiber cable - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate the burial pipings to respective houses and enables the additional burial pipings in future if necessary even if the diameter of a sewer pipe is small. SOLUTION: A box branch pipe 15 comprising a drain branch part 17 and a covered box 19 is provided in a sewer pipe 3 comprising a duct, and a sheath pipe branch part 29 is inserted in a sheath pipe 5 laid in the covered box 19. A drain branch pipe 35 connected to a public box is connected to the drain branch 17 of the box branch pipe 15. After a flexible sheath pipe 33 connected to the sheath pipe branch 29 in the covered box 19 is drawn out, the flexible sheath pipe 33 is laid to the public box along the outer circumference of the drain branch pipe 35. A messenger wire is fed into the flexible sheath pipe 33 from its feed-in opening on its public box side until the wire reaches a manhole. An optical fiber cable is connected to the messenger wire leading to the manhole, and the messenger wire is pulled back through the feed-in opening to install the optical fiber cable from the manhole to the feed-in opening.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical fiber cable laying method for laying an optical fiber cable to each house by buried piping.

[0002]

2. Description of the Related Art In recent years, optical cables capable of transmitting a larger amount of signals than telecommunication lines have been buried. To lay a new optical fiber cable underground, earth pressure,
Material costs and burial costs increase due to protection from external factors such as impacts. Therefore, it has been proposed to lay an optical fiber cable using an existing or newly installed sewer pipe, and some have begun to realize it.

In this type of optical fiber cable laying method, a sheath through which an optical fiber cable is inserted is disposed in a sewer pipe connecting between manholes, and the optical fiber cable is inserted between the manholes through the sheath. It is common to make a line. Further, the optical fiber cable is branched into a plurality of parts by a distributor provided in each manhole.

Conventionally, the optical fiber cable branched in this way is drawn out of the manhole from a through hole formed in the side wall of the manhole. And the optical fiber cable pulled out of the manhole was extended to a telephone pole on the ground, and was wired to each house by an aerial.

[0005]

However, the aerial wiring of the optical fiber cable has a problem that the view is spoiled and that the cable is easily affected by wind and rain. Therefore, it is desirable to lay the optical fiber cable branched in the manhole to each house with buried piping as much as possible. However, the conventional laying method has the following problems. In other words, when the diameter of the sewer pipe is as small as about 150 mm in inner diameter, it becomes difficult to pierce the sewer pipe, and it is impossible to branch the optical fiber cable from the sewer pipe. Did not.

[0006] The sewage branch pipe branched from the sewage pipe is:
Although pipes are installed near each house, it was difficult to lay optical fiber cables using the inside of the sewage branch pipe due to the small diameter and blockage. Furthermore, even in the case where an optical fiber cable is branched in the future, it is difficult to pierce and lay the sewer pipe for the above-mentioned reason, and as a result, aerial wiring from the manhole was forced.

The present invention has been made in view of the above circumstances, and even in the case of a small-diameter sewer pipe, buried piping can be easily performed to each house using a sewage branch pipe, and future optical fiber cables will be used. Even if a branch occurs,
It is an object of the present invention to provide a method of laying an optical fiber cable which enables a buried pipe to be easily provided to each house while taking a form of a buried pipe.

[0008]

Next, means for solving the above problems will be described with reference to the drawings corresponding to the embodiments. The method for laying an optical fiber cable according to claim 1 of the present invention is a method for laying an optical fiber cable for branching an optical fiber cable inserted into a sheath 5 supported in a tube 3 constituting a conduit, The pipe 3 is provided with a branch pipe 15 having a branch section 17 and a box 19 with a lid. The sheath pipe 5 passing through the box 19 with the lid is interposed with a branch section 29 for a sheath. A branch pipe 35 connected to a public box 37 is connected to the branch section 17 of the branch pipe 15, and the flexibility and the pipe 33 connected to the sheath pipe branch section 29 in the box 19 with the lid are connected to the side of the box 19 with the lid. After passing through to the outside, the pipe is laid along the outer circumference of the branch pipe 35 to the public tub 37, and the flexible tubing 33 is drawn into the inlet 39 on the side of the public tub 37, and the lid-attached tub is taken out. 19 through the pod pipe branch portion 29 in the pipe body 3 Feeding the messenger wire 41 to the manhole 1 provided downstream, messenger wire 41 has reached the manhole 1
The optical fiber cable is connected from the manhole 1 to the inlet port 39 by connecting an optical fiber cable to the end of the cable and pulling back the messenger wire 41 from the inlet port 39.

In this method of laying an optical fiber cable, a branch pipe 15 with a tub having a branch portion 17 and a tub 19 with a lid is provided.
Is provided in the pipe body 3 constituting the pipeline, and the branch pipe 35 can be easily connected via the branch portion 17 of the branch pipe 15 with a square. Further, the flexibility and the pipe 33 can be laid to the public square 37 using the branch pipe 35. On this occasion,
Considering the obstruction in the branch pipe 35, the flexibility and the pipe 33 are preferably along the outer circumference of the branch pipe 35. However, conventionally, if the diameter of the tube is 150 mm or less, it is difficult to pierce the tube, and it has been difficult to guide the sheath tube 5 out of the tube 3. On the other hand, in the present invention, the box
Is provided, so it is impossible to drill 150mm
Also in the case of the tubular body 3, the flexibility and the pipe 33 can be easily led out from the branch pipe 15 with a square, and piping along the branch pipe 35 becomes possible. As a result, the optical fiber cable does not have to be directly led out from the manhole 1, and buried piping close to each house can be provided.

According to the method of laying an optical fiber cable according to a second aspect of the present invention, the branch portion 17 is closed by a removable plug at a desired position of the tube 3 where the optical fiber cable needs to be branched in the future. The branch pipe 1 with a square
5 is provided, and when it becomes necessary to branch the optical fiber cable, the plug is removed and the branch pipe 35 is connected to the branching section 17.
1 is opened and the sheath pipe branch portion 29 in the box 19 with the lid is opened.
After the flexible tube 33 connected to the tube is penetrated through the side surface of the box 19 with the lid and led out to the outside, the tube is piped along the outer circumference of the branch tube 35 to the public box 37, and the flexible tube is connected. 33
The messenger wire 41 is sent from the inlet 39 on the side of the public box 37 to the manhole 1 provided downstream of the tube 3 through the sheath 29 in the box 19 with the lid. An optical fiber cable is connected to the tip of the messenger wire 41 that has reached the inside, and the messenger wire 41 is inserted into the inlet 39.
The optical fiber cable is drawn from the manhole 1 to the drawing port 39 by pulling back from the manhole 1.

In this method of laying an optical fiber cable, the branch pipe 15 with a square is provided at a desired location 34 of the pipe 3 where the optical fiber cable needs to be branched in the future. When it becomes, the lid 31 of the box 19 with the lid is opened and the box 19 with the lid is opened.
The flexible sheath 33 can easily be connected to the inner sheath branch part 29. Thereby, after the flexible sheath 33 connected to the sheath pipe branch part 29 is led out to the outside by penetrating the side surface of the box 19 with a lid, piping along the outer periphery of the branch pipe 35 to the public square 37 is performed. Becomes possible. That is, it is possible to easily cope with future branching of the optical fiber cable while taking the form of laying the buried piping.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a method for laying an optical fiber cable according to the present invention will be described below in detail with reference to the drawings. 1 is a side view showing a tube laid by the method according to the present invention, FIG. 2 is an enlarged view of a main part of FIG. 1,
FIG. 3 is an explanatory view showing the connection procedure of the sheath pipe and the pipe body in (a) to (c), and FIG.

In order to carry out the method for laying an optical fiber cable according to the present invention, it is necessary to connect the manholes 1 with a drain pipe 3 as a pipe. Sewage pipe 3
Can have a small diameter of 150 mm or less. A sheath 5 through which an optical fiber cable is inserted is attached to the sewer pipe 3 in advance. The sheath pipe 5 is attached to the upper part of the inner periphery of the drain pipe 3 using the cable protection pipe support 7.

The cable protection tube support 7 has a cylindrical portion 11 for inserting and supporting the sheath tube 5 at a substantially central portion of an adhesive plate 9 curved in an arc shape with a radius of curvature substantially equal to the radius of the sewer pipe 3. Have. Accordingly, a plurality of cable protection tube supports 7 are bonded and fixed to the upper portion of the inner periphery of the sewer pipe 3 at predetermined intervals in the pipe axis direction, and the sheath tube 5 is inserted through the inner periphery of the cylindrical portion 11 to thereby reduce the sewer pipe. A sheath tube 5 is supported at a predetermined interval on an inner peripheral upper portion of 3.

At the branch of the sewer pipe 3 where the optical fiber cable is branched, a branch pipe 15 with a square is provided. Branch pipe with basin 15
Constitutes a special joint in which the sewage branching portion 17 and the lid-covered box 19 are connected and integrated. Branch pipe with basin 15
Is attached to the sewage pipe 3 in a direction in which the sewage branching portion 17 is arranged on the upstream side in the sewage flow down direction and the lid-covered box 19 is arranged on the downstream side. In the branch pipe 15 with a basin, the connection port of the basin 19 with a lid, which is on the downstream side, is the insertion port 21, and the connection port of the branch portion 17 for sewage, which is on the upstream side, is the reception port 23.

A plurality of branch ports 17a of the sewage branch section 17 are provided as necessary. A detachable plug (not shown) can be attached to the branch port 17a. In other words, it is possible to remove and use the obstruction plug of only the necessary branch port 17a and leave the unnecessary branch port 17a with the obstruction plug attached.

The sheath tube 5 is also supported in the vicinity of the branch tube 15 with a tub. The sheath tube 5 in the branch tube 15 with a basin is
In the present embodiment, as shown in FIG.
It is supported at one location on one side and at two locations in the vicinity of the receiving port 23 of the sewage branch 17. The above-described cable protection tube support 7 is used as the support on the insertion port 21 side.
On the other hand, as the support on the receiving port 23 side, a support 27 having a structure in which the cylindrical portion 11 is bonded, welded, or screw-fixed to the inner surface of the tubular body without using the adhesive plate 9 is used.

The use of the support 27 for directly fixing the tubular portion 11 to the sewage branch 17 eliminates the need for the adhesive plate 9 and provides a plurality of branch openings 17a provided in the sewage branch 17.
Can be supported without closing the internal opening of the sheath.

A sheath pipe branching portion 29 is provided in the sheath tube 5 in the box 19 with a lid. The sheath pipe branching portion 29 is a substantially y-shaped tubular body from which an optical fiber cable inserted through the sheath tube 5 can be taken out. By opening the lid 31 of the box 19 with the lid, the sheath 33 can be connected to the branch part 29 for the sheath. As the flexible tube 33, a flexible olefin resin tube such as PE (polyethylene), PP (polypropylene), or PB (polybutene) is used.

A method of laying an optical fiber cable using the branch pipe 15 having the above-described configuration will be described. A drain 3 is connected between the manholes 1. A sheath pipe 5 is attached to an upper portion of the inner periphery of the drain pipe 3 in advance by a cable protection pipe support 7. As shown in FIG. 3 (a), the connection of the sewer pipes 3 is performed by aligning the two sewer pipes 3, 3 so that the sheath pipe 5 is at the top.
An adhesive is applied to the insertion opening 5a of the one sheath 5 and the socket 5b of the other sheath 5. Next, as shown in FIG. 3B, the insertion port 5a is inserted into the socket 5b, and the sheath 5
Complete the connection between them.

Next, as shown in FIG. 3C, a lubricant is applied to the insertion opening 3a and the receiving opening 3b of the drain pipe 3, and the inserting opening 3a is inserted into the receiving opening 3b using a lever block (not shown). Then, the connection between the sewer pipes 3 is completed.

When connecting the branch pipe 15 with a square to the sewer pipe 3, first, the insertion port 5 a of the sheath 5 supported by the branch pipe 15 with the square is connected to the sheath 5 provided in the drain pipe 3. Into the socket 5b. After that, the insertion port 21 of the branch pipe 15 with a square is inserted into the receiving port 3b of the sewer pipe 3 using a lever block. Further, the sheath 5a of the sheath 5 is inserted into the socket 5b of the sheath 5 located at the receptacle 3b of the branch pipe 15 with a tub, and the socket 5a of the sheath 5 located at the inlet 3a of the drain pipe 3 on the upstream side in the downflow direction. 5
After connecting each other, the insertion port 3a of the sewage pipe 3 on the upstream side in the flow-down direction is connected to the receiving port 2 of the branch pipe 15 with a square using a lever block.
3 to complete the connection of the upstream-side sewer pipe 3 to the branch pipe 15 with a square. As a result, a branch pipe 15 with a tub having the sheath 5 inserted therein is interposed at a desired location of the sewer pipe 3.

At this time, as shown in FIG. 4, the branch pipe 15 with a square is also interposed at a portion 34 where the optical fiber cable needs to be branched in the future. In this case, the branch pipe 1
The fifth branch port 17a is closed by the closing plug as described above.

Next, a sewage branch pipe 35 serving as a branch pipe is connected to a branch port 17a of the sewage branch section 17 in the branch pipe 15 with a basin.
Connect. The sewage branch pipe 35 is connected so as to be connected to a public square 37 buried adjacent to each house H. Next, the lid 31 of the box 19 with the lid of the branch pipe 15 with the box is opened, and the flexible pipe 33 is connected to the branch portion 29 for the sheath in the box 19 with the lid. The flexible tube 33 penetrates through the side surface of the box 19 with a lid, and is led out to the outside.
Piping along the outer circumference of. The flexibility and the tube 33 are
Piping is performed gently along the sewage branch pipe 35 without bending. The penetrating portion of the box 19 with a lid is sealed with silicon caulking or the like. The flexibility and the tube 33 are
It is attached to the outer periphery of the sewage branch pipe 35 by a resin belt 38, a stainless belt, a string or the like.

In this way, the space between the public square 37 buried near each house H and the manhole 1 is connected by the sheath tube 5 and the flexible tube 33.

Next, from the inlet 39 of the flexible tube 33 on the side of the public box 37, the branch 2 for the sheath tube in the box 19 with the lid is opened.
9, the messenger wire 41 is sent to the manhole 1 provided downstream of the sewer pipe 3. As the messenger wire 41, for example, a PET wire or the like that has rigidity and can be inserted without being bent is used.

An optical fiber cable is connected to the end of the messenger wire 41 that has reached the inside of the manhole 1.
Next, by pulling back the messenger wire 41 from the inlet 39, the optical fiber cable is drawn from the manhole 1 to the inlet 39. As a result, the optical fiber cable is transferred from the manhole 1 to the branch pipe 1
The laying is completed through the route 5 to the public square 37 on the house site.

It is assumed that the connection of the optical fiber cable from the public square 37 to each house H is laid by a separate construction.

Also, once the installation of the optical fiber cable is completed, when branching of the optical fiber cable becomes necessary, that is, when a new house H 'is constructed, the optical fiber cable is buried in advance as described above. The exposed branch pipe 15 with a basin is exposed. The obstruction plug attached to the branch port 17a of the branch pipe 15 with a basin is removed, and a sewage branch pipe 35 is newly provided at the branch port 17a.

Next, the lid 31 of the box 19 with the lid is opened, and the flexible pipe 33 is connected to the branch 29 for the sheath in the box 19 with the lid. In the same manner as described above, the flexibility and the pipe 33 are pierced through the side surface of the box 19 with the lid and led out to the outside, and then piped along the outer periphery of the sewage branch pipe 35 to the public box 37. Hereinafter, as in the case of the above-mentioned new installation, the flexibility and the inlet 3 of the pipe 33 are set.
By sending the messenger wire 41 from the connector 9 to the manhole 1 and pulling out the optical fiber cable connected in the manhole 1 from the inlet 39, the optical fiber cable can be laid.

[0031]

As described above in detail, according to the method for laying an optical fiber cable according to the present invention, since the branch pipe with the tub having the branch part and the tub with the lid is provided in the pipe body, the branch pipe is formed. The connection can be easily made, and the flexibility and the pipe can be laid to the public measure using the branch pipe. On this occasion,
It is preferable that a flexible pipe is provided along the outer circumference of the branch pipe, and even in the case of a thin pipe body having a diameter of 150 mm or the like, which cannot be pierced, since a tube with a lid is provided, the flexibility and the pipe can be easily formed. The pipe can be pulled out to the outside of the pipe via a branch pipe with a square, and can be piped along the branch pipe. As a result, as before,
It is not necessary to derive optical fiber cables directly from manholes, and buried piping close to each house is made possible, and aerial wiring using telephone poles and the like can be reduced as much as possible.

Further, since the branch pipe with a basin having a lid is provided, the branch pipe with the basin is provided at a location of the pipe where the branch of the optical fiber cable is required in the future, so that the branch of the optical fiber cable is provided. When it becomes necessary, open the lid of the box with a lid, connect a flexible tube to the branch for the sheath in the box with the lid, and penetrate the side of the box with the lid and lead it out to the outside The pipe can be piped along the outer circumference of the branch pipe to the public basin. Thus, it is possible to easily cope with future branching of the optical fiber cable while laying the buried piping.

[Brief description of the drawings]

FIG. 1 is a side view showing a sewer pipe laid by a method according to the present invention.

FIG. 2 is an enlarged view of a main part of FIG.

FIG. 3 shows connection procedures of a sheath pipe and a sewer pipe (a) to (c).
FIG.

FIG. 4 is an explanatory view showing a required location of a branch pipe with a basin.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Manhole 3 ... Pipe body (sewage pipe) 5 ... Sheath pipe 15 ... Branch pipe with a square 17 ... Branch part 19 ... Square with a lid 29 ... Branch part for sheath pipe 31 ... Lid 33 ... Flexible sheath 35 ... Branch pipe ( Sewage branch pipe) 37 ... Public basin 39 ... Inlet 41 ... Messenger wire

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Yoshikazu Hashizume 1-1-18 Kyobashi, Chuo-ku, Tokyo Inside C-I Kasei Corporation (72) Inventor Hiroto Sugawara 1-16-1 Kyobashi, Chuo-ku, Tokyo No. F-term (reference) in Shiai Kasei Co., Ltd. 2D063 BA20 BA31 2H038 CA68

Claims (2)

[Claims] 1. A method for laying an optical fiber cable for branching an optical fiber cable inserted into a sheath supported in a pipe constituting a pipe, wherein the pipe comprises a branch portion and a lid-covered box. A branch pipe with a basin is provided, a tubing branch part is interposed on the pod tube passing through the basin with a lid, and a branch pipe connected to a public basin is connected to a branch part of the branch pipe with a basin. After the flexible sheath or tube connected to the sheath tube branch part in the basin is led out through the side surface of the covered basin,
Piping is performed along the outer circumference of the branch pipe to the public basin, from the inlet of the flexible tubing on the side of the public basin through the pod pipe branching section in the hood with the lid, and downstream of the pipe body. The messenger wire is sent to the manhole provided in the, the optical fiber cable is connected to the tip of the messenger wire that has reached the inside of the manhole, and the messenger wire is pulled back from the inlet, so that the optical fiber cable is moved from the manhole to the inlet. A method of laying an optical fiber cable, wherein the optical fiber cable is drawn. 2. The optical fiber cable according to claim 1, wherein said branch pipe is provided at a desired position of said pipe body where a branch of said optical fiber cable is required in the future. When it becomes necessary to branch the cable, the plug is removed, the branch pipe is connected to the branch part, the lid of the box with the lid is opened, and the branch is connected to the branch part for the sheath in the box with the lid. After drawing out the flexibility and the pipe to the outside by penetrating the side face of the box with the lid, and piping along the outer circumference of the branch pipe to the public box, A messenger wire is sent from the inlet through a sheath for branch in the box with a lid to a manhole provided downstream of the tubular body, and an optical fiber cable is connected to the tip of the messenger wire that has reached the manhole. By connecting, by pulling back the gland the messenger wire, laying method for an optical fiber cable of claim 1, wherein the pull a fiber optic cable from the manhole to the gland.