JP7134078B2 - Optical cable laying method and optical cable laying structure - Google Patents

Description

The present invention relates to an optical cable laying method and an optical cable laying structure for replacing a part of an existing optical cable.

2. Description of the Related Art Conventionally, in order to lay an optical cable or the like in a building such as a residence, the optical cable is branched by a closure formed near a utility pole installed outdoors, and the optical cable is pulled down to each building.

FIG. 6 is a conceptual diagram showing the optical cable installation structure 100. As shown in FIG. A trunk cable laid on the utility pole 11 is introduced into a closure 3 formed in the vicinity of the utility pole 11 . A necessary optical fiber is branched from the closure 3, connected to the optical cable with support line 1, and then dropped to the building 5a at the drop-off section 5. FIG. The optical cable with support line 1 is, for example, a self-supporting drop cable having a support line and an optical fiber core.

The optical cable 1 with a support line branched from and connected to the closure 3 has its support line separated near the utility pole 11 and is anchored to the utility pole 11 by an anchor or the like. However, depending on the usage pattern of the utility pole 11, it is not possible to use anchors or the like, and as shown in FIG. . In this case, between the utility poles 11, the optical cable 1 with the support wire is supported by the messenger wire (suspension wire) 7 by the spiral hanger 9, and in the vicinity of the utility pole 11, after being fixed to the messenger wire 7 by a binding string or the like, the utility pole 11 is It is laid as a bridge.

FIG. 7(a) is a conceptual plan view of the X section of FIG. As described above, it is not necessary to form the connecting portion of the optical cable with support wire 1 between the closure 3 and the pull-down portion 5 at the beginning of laying the optical cable with support wire 1 . However, for example, when updating the utility pole 11, as shown in FIG. Arrow Y) in the figure is necessary.

In such a case, if the length of the installation line of the optical cable with support line 1 is long, there is a possibility that the length of the optical cable will be insufficient. Therefore, as shown in FIG. 7(c), it is necessary to cut a part of the optical cable 1 with support wire and connect a new additional optical cable in the optical cable additional range 13. FIG.

In this case, the connecting portion 14 between the optical cables may be a weak point against tension and bending compared to other portions, so various reinforcements are applied (for example, Patent Documents 1 and 2). Also, the connection portion 14 includes a connection portion between support wires and a connection between optical cables (optical fibers). For this reason, the connecting portion 14 usually has a larger outer diameter than other portions.

JP 2011-159932 A JP-A-2006-65170

As described above, when a new optical cable is spliced to a part of the optical cable with support wire 1 , the connecting portion 14 is positioned inside the spiral hanger 9 . However, if the connecting portion 14 is positioned inside the spiral hanger 9, the connecting portion 14 may be caught on the spiral hanger 9, and the connecting portion 14 may be damaged. Also, when another optical cable is inserted through the spiral hanger 9, contact with the connection portion 14 may damage the optical cable. Furthermore, since the connecting portion 14 is thick, if a plurality of connecting portions 14 are arranged in the spiral hanger 9, it may be difficult to insert a new optical cable.

On the other hand, as a method of not forming the connection portion 15, there is a method of replacing all the existing optical cables 1 with support wires from the closure 3 to the building 5a. However, in this method, since the worker needs to enter the building 5a, it is necessary to coordinate the time with the manager, residents, etc. of the building 5a, and the work is inefficient. In addition, if a new optical cable is to be connected to the end of the trunk cable drawn into the closure 3, a surplus length of the optical fiber required for connection is required in the closure. There is no extra length, and the connection length of the optical fiber may not be ensured. Moreover, there is a possibility that other optical fibers connected to the closure 3 may be adversely affected during construction.

SUMMARY OF THE INVENTION The present invention has been made in view of such problems. To provide an optical cable laying method or the like capable of easily exchanging an optical cable while keeping a small size.

In order to achieve the above object, the first invention comprises a closure, an optical cable pulled out from the closure and laid to a draw-down section, and a spiral hanger supporting the optical cable between utility poles supporting the optical cable. and a messenger wire stretched between the utility poles, the step of placing a new optical cable on the spiral hanger between the pull-down portion and the closure; A step of cutting the existing optical cable and connecting the new optical cable between the introduction part to the spiral hanger and cutting the existing optical cable between the withdrawal part and the introduction part to the spiral hanger. cutting and connecting the new optical cable, and between the closure to the lead-in portion to the spiral hanger and between the drop-off portion to the lead-in portion to the spiral hanger, the existing wherein the existing optical cable and the new optical cable are optical cables with support wires, and between the withdrawal part and the introduction part to the spiral hanger , one ends of the support wires of the existing optical cable and the new optical cable are respectively fixed to anchors installed on the messenger wires, and the connecting portion between the existing optical cable and the new optical cable is connected to the support wire. The optical cable laying method is characterized in that the optical cable is not included .

The new optical cable may be longer than the existing optical cable from the closure to the withdrawal section.

A connecting portion between the existing optical cable and the new optical cable is covered with a protective tube between the closure and the lead-in portion to the spiral hanger and between the pull-down portion and the lead-in portion to the spiral hanger. and the protective tube may have markings.

When at least part of the utility pole is relocated or replaced and the length of the installed optical cable after the relocation or replacement becomes longer than the length of the existing optical cable, the existing optical cable is replaced with the new cable that is longer than the existing optical cable. You can replace it with an optical cable.

According to the first invention, since the connection portion is not located inside the spiral hanger, when another optical cable is inserted through the spiral hanger, the connection portion hinders the insertion of the other optical cable, or prevents the other optical cable from being inserted through the spiral hanger. It is possible to prevent the optical cable or the like from being damaged.

In particular, if the newly added optical cable is longer than the existing optical cable, the installation length of the optical cable can be extended.

Further, by providing a mark on the protective tube that protects the connection portion and the optical cable near the connection portion, it is possible to distinguish the protection tube from the protective tubes in other portions where the connection portion is not arranged. Therefore, it is possible to call attention to the operator when handling the protective tube in which the connecting portion is accommodated.

Such an optical cable replacement method is particularly effective when the length of the optical cable to be installed becomes long when the utility pole is relocated or replaced.

A second invention comprises a closure, an optical cable pulled out from the closure and laid up to a pull-down section, a spiral hanger supporting the optical cable between the utility poles supporting the optical cable, and a spiral hanger stretched between the utility poles. and a messenger wire, wherein connecting portions of the optical cable are positioned between the closure to the lead-in portion to the spiral hanger and between the draw-down portion to the lead-in portion to the spiral hanger, and the optical cable is An optical cable with a support line, wherein one end of the support line of each of the optical cables connected at the connection section is installed on the messenger wire between the pull-down section and the lead-in section to the spiral hanger. The optical cable installation structure is characterized in that the optical cable is fixed to each fixture, and the connection part does not include the support line .

According to the second invention, when another optical cable is inserted through the spiral hanger, the connection part does not interfere with the insertion of the other optical cable or damage the other optical cable. structure can be obtained.

According to the present invention, when replacing an existing optical cable, it is possible to prevent a connecting portion from being positioned in a spiral hanger, and to provide an optical cable laying method or the like that enables easy replacement of the optical cable. can be done.

4 is a flow chart showing a method of laying (replacing) the optical cable with support line 1. FIG. (a), (b) is a figure which shows the replacement|exchange process of the optical cable with a support line 1. FIG. (a), (b) is a figure which shows the replacement|exchange process of the optical cable with a support line 1. FIG. (a), (b) is a figure which shows the replacement|exchange process of the optical cable with a support line 1. FIG. FIG. 3 is a diagram showing an optical cable installation structure 30; The figure which shows the conventional optical cable installation structure 100. FIG. (a), (b), and (c) are diagrams showing a conventional replacement process for the optical cable with support line 1. FIG.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a flow chart showing a method of laying an existing optical cable with support line 1. FIG. In the present embodiment, a description will be given of an optical cable replacement method (installation method) for the optical cable installation structure 100 shown in FIG.

As described above, the optical cable laying structure 100 supports the closure 3, the existing optical cable 1 with support line pulled out from the closure 3 and laid up to the drop-off section 5 for users, etc., and the optical cable with support line 1. and a spiral hanger 9 for supporting the optical cable 1 with a support wire between a plurality of utility poles 11.

First, in the optical cable laying structure 100 shown in FIG. 6, a new optical cable 20 with a predetermined length is arranged on the spiral hanger 9 between the closure 3 and the withdrawal section 5 (step 101).

FIG. 2(a) is a diagram showing a process of inserting the optical cable with support line 20 into the spiral hanger 9 along the optical cable with support line 1 (arrow A in the figure). In the following figures, illustration of the utility pole 11 and the building 5a is omitted. Further, the optical cable with support line 1 and the new optical cable with support line 20 are, for example, normal self-supporting drop cables, but the illustration and description of the tension member, the jacket, etc. are omitted, and the internal support line and optical cable are omitted. Only the fibers are shown and described. Also, in the following description and illustrations, only one optical fiber is shown, but an optical cable having a desired number of two or more may be used.

An optical cable 1 with a support line includes an optical cable 1a including an optical fiber and a support line 1b. The support line 1b and the optical cable 1a are separated in the vicinity of the retaining portion of the support line 1b. A protective tube 17 is arranged at a portion where the support line 1b is separated and only the optical cable 1a is provided. The protective tube 17 is a tube having a split portion along the longitudinal direction, and covers the optical cable 1a to protect the optical cable 1a.

FIG. 2(b) is a diagram showing a state in which the optical cable 20 with a support line is laid from the vicinity of the closure 3 to the vicinity of the pull-down portion 5. As shown in FIG. The optical cable with support line 20 is laid longer than the optical cable with support line 1 in the same range. In this state, first, in the vicinity of the end of the optical cable 20 with the support line on the closure 3 side, the support line 20b and the optical cable 20a including the optical fiber are separated.

Next, the optical cable 1 with support wire 1 is cut between the introduction portion from the closure 3 to the spiral hanger 9 (B portion in FIG. 3A) (step 102). Next, as shown in FIG. 3(b), the optical cable 1a of the existing optical cable with support line 1 pulled out from the closure 3 and the optical cable 20a of the newly installed optical cable with support line 20 are connected by a fusion splicer or the like. Optical connection is made using the optical fiber (step 103). The connecting portion 15 between the optical cable 1a and the optical cable 20a is reinforced with a reinforcing member and a reinforcing sleeve after fusion splicing, for example.

After that, signal light is introduced from the trunk cable side into the optical cable with support line 1, and the signal light is received at the end of the optical cable with support line 20 on the withdrawal part 5 side (arrow C in the figure). That is, the state of the optical connection between the optical cable 1a and the optical cable 20a is confirmed (step 104). If there is a problem with the optical connection, the work is redone from step 103 .

Next, as shown in FIG. 4A, the support line 1b of the existing optical cable with support line 1 pulled out from the closure 3 to the cut portion is removed, and the support line 20b of the optical cable with support line 20 and the closure 3 are removed. and secure it. That is, the optical fibers of the optical cable with support line 1 and the optical fiber with support line 20 are connected to each other. A protective tube 17a is attached to the outer periphery near the connecting portion 15 between the optical cable 1a and the optical cable 20a. The protective tube 17a includes the connecting portion 15 and is attached to the outer periphery of the exposed portion of the optical cable 1a (step 105).

The protective tube 17a may be the same as the protective tube 17 used before replacement, but preferably has some kind of mark. As such a mark, for example, where a normal protective tube is black, it may be colored to a different color, or a protective tube having an outer diameter different from that of a normal protective tube may be used. By providing such a mark, it is possible to inform the operator that the connecting portion 15 is accommodated inside.

Next, the optical cable 1 with the support line is cut between the withdrawal section 5 (building 5a) and the lead-in section to the spiral hanger 9 (sections D1 and D2 in FIG. 4(a)). (Step 106). Next, as shown in FIG. 4(b), in the vicinity of the end of the optical cable with support line 20 on the withdrawal part 5 side, the support line 20b and the optical cable 20a are separated, and the optical cable with support line is pulled out from the building 5a. 1 and the optical fiber of the optical cable 20a of the optical cable 20 with support line are optically connected (step 107). As described above, the connection portion 15 between the optical cable 1a and the optical cable 20a is reinforced with a reinforcing member and a reinforcing sleeve after fusion splicing, for example.

Thereafter, signal light is introduced from the trunk cable side into the optical cable 1 with support line, and the terminal device in the building 5a receives the signal light to confirm the state of the optical connection between the optical cable 1a and the optical cable 20a (step 108). . If there is a problem with the optical connection, the operation is redone from step 107 .

Next, as shown in FIG. 5, the support line 1b of the optical cable with support line 1 pulled out from the building 5a and the support line 20b of the optical cable with support line 20 are fixed by anchors installed on the messenger wire 7. . A protective tube 17b is attached to the outer periphery near the connecting portion 15 between the optical cable 1a and the optical cable 20a. The protective tube 17b includes the connection portion 15 and is attached to the outer circumference of the exposed portion of the optical cable 1a (step 109).

Finally, the optical cable installation structure 30 can be obtained by removing the optical cable 1 with the support wire in the spiral hanger 9 . That is, the optical cable 1 with support wire in the spiral hanger 9 can be replaced with the optical cable 20 with support wire. In addition, when the length of the optical cable with support wire 20 is increased with respect to the optical cable with support wire 1 to be removed, for example, between the connection part 15 on the withdrawal part 5 side and the introduction part to the spiral hanger 9 , round the extra length and fix it.

The optical cable installation structure 30 thus obtained includes the closure 3, the optical cables 1 and 20 with support wires that are pulled out from the closure 3 and laid up to the withdrawal section 5 for the user, and the cable with support wires. A spiral hanger 9 for supporting the optical cable 20 with support wire is provided between a plurality of utility poles 11 for supporting the optical cable 20 .

At this time, the connection portion 15 between the optical cable 1 a and the optical cable 20 a is arranged outside the spiral hanger 9 . That is, the connecting portion 15 of the optical cable 1a and the optical cable 20a is positioned between the closure 3 and the lead-in portion to the spiral hanger 9 and between the drop-off portion 5 and the lead-in portion to the spiral hanger 9 .

As described above, according to this embodiment, the connection portion 15 between the optical cable 1a and the optical cable 20a is not arranged inside the spiral hanger 9 . Therefore, the optical cable 20 with support line does not move with respect to the spiral hanger 9, and the connecting portion 15, which is thicker than other portions, does not get caught on the spiral hanger 9. - 特許庁For example, as described above, the connection portion 15 does not move within the spiral hanger 9 even when the installation line length is increased due to the relocation of the utility pole 11 or the like. Moreover, the connection portion 15 does not include the connection portion of the support wires 1b and 20b, and has a smaller diameter than the connection portion 14 (see FIG. 7(c)) including the connection portion between the conventional support wires. Therefore, the connecting portion 15 is not damaged, and the connecting portion 15 does not interfere with the laying of other optical cables.

In this way, as described above, the present embodiment can be used when at least a portion of the utility pole 11 is relocated or replaced, and the optical cable installation length after relocation or replacement becomes longer than the existing optical cable installation length. It is particularly effective for replacing the optical cable 1 with a support line with a new optical cable 20 with a support line longer than the optical cable 1 with a support line. Even if the installation length does not change, the present embodiment can also be applied to a case where the optical cable 1 is replaced due to damage to the optical cable.

In addition, since the optical cable with support line 1 remains on the closure 3 side (E part in FIG. 5) than the connection part 15 and on the building 5a side (F part in FIG. 5) than the connection part 15, There is no need for extra length inside the closure 3.

Also, if the protection tubes 17a and 17b in which the connecting portion 15 is housed have marks for the protection tubes 17 used in other parts, it will alert the operator.

Although the embodiments of the present invention have been described above with reference to the accompanying drawings, the technical scope of the present invention is not influenced by the above-described embodiments. In particular, in this specification, a case in which the length of the existing optical cable is short due to the relocation of a utility pole has been described as an example, but the present invention is not limited to this, and can be widely applied to replacement of existing optical cables. is. In addition, it is clear that a person skilled in the art can conceive of various modifications or modifications within the scope of the technical idea described in the claims for the technical scope of the present invention. are naturally within the technical scope of the present invention.

Reference Signs List 1 Optical cable with supporting wire 1a Optical cable 1b Supporting wire 3 Closure 5 Withdrawal part 5a Building 7 Messenger wire 9 Spiral hanger 11, 11a …………Telephone pole 13…………Optical cable additional range 14, 15……Connecting parts 17, 17a, 17b……Protective tube 20…………Optical cable with supporting wire 20a……Optical cable 20b…………Supporting wire 30, 100 …… Optical cable installation structure

Claims (7)

a closure;
an optical cable that is pulled out from the closure and laid to a withdrawal part;
a spiral hanger supporting the optical cable between utility poles supporting the optical cable;
a messenger wire stretched between the utility poles;
In an optical cable installation structure comprising
arranging a new optical cable on the spiral hanger between the pull-down portion and the closure;
a step of cutting the existing optical cable and connecting the new optical cable between the closure and the lead-in portion to the spiral hanger;
a step of cutting the existing optical cable from the withdrawal portion to the lead-in portion to the spiral hanger and connecting the new optical cable;
and
Disposing a connecting portion between the existing optical cable and the new optical cable between the closure and the lead-in portion to the spiral hanger and between the pull-down portion and the lead-in portion to the spiral hanger ,
The existing optical cable and the new optical cable are optical cables with support wires,
One ends of the support wires of the existing optical cable and the new optical cable are respectively fixed to anchors installed on the messenger wire between the pull-down portion and the lead-in portion to the spiral hanger,
A method of laying an optical cable , wherein a connection portion between the existing optical cable and the new optical cable does not include the support line . 2. The method of laying an optical cable according to claim 1 , wherein the other end of the support wire of said new optical cable is connected to said closure . 3. The optical cable laying method according to claim 1, wherein the new optical cable is longer than the existing optical cable from the closure to the pull-down portion. A connecting portion between the existing optical cable and the new optical cable is covered with a protective tube between the closure and the lead-in portion to the spiral hanger and between the pull-down portion and the lead-in portion to the spiral hanger. 4. The method of laying an optical cable according to claim 1, wherein the protective tube has a mark. When at least part of the utility pole is relocated or replaced and the length of the installed optical cable after the relocation or replacement becomes longer than the length of the existing optical cable, the existing optical cable is replaced with the new cable that is longer than the existing optical cable. 5. The method of laying an optical cable according to claim 1 , wherein the optical cable is replaced with an optical cable. a closure;
an optical cable that is pulled out from the closure and laid to a withdrawal part;
a spiral hanger supporting the optical cable between utility poles supporting the optical cable;
a messenger wire stretched between the utility poles;
and
A connecting portion of the optical cable is positioned between the closure and the lead-in portion to the spiral hanger and between the pull-down portion and the lead-in portion to the spiral hanger ,
The optical cable is an optical cable with a support wire,
one end of each of the support wires of each of the optical cables connected at the connecting portion between the pull-down portion and the lead-in portion to the spiral hanger is fixed to an anchor attached to the messenger wire;
The optical cable installation structure , wherein the connecting portion does not include the support line . 7. The optical cable installation structure according to claim 6, wherein the other end of said support line of said optical cable on said spiral hanger side of said respective optical cables is connected to said closure.

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