JP4433333B2 - Connection method of nominal wire and communication cable - Google Patents

Description

  The present invention is inserted into a guide pipe laid in an underground conduit where a plurality of branch pipes are branched into a main pipe such as a sewer pipe, a communication pipe, a power pipe, etc., and a communication cable can be easily inserted when necessary. The present invention relates to a connection method between a call line and a communication cable.

  Currently, construction of a high-speed / ultra-high-speed communication network is underway, and there are two methods for laying a communication cable as a medium: an aerial method and an underground method. The communication cable laying in the underground burial method has characteristics such as protecting the spatial environment (aesthetics of the ground landscape, etc.) and being resistant to disasters such as earthquakes and typhoons, compared to the laying method in the aerial method. In particular, sewer pipes in underground pipes have branch pipes (mounting pipes) that are connected to the main pipes already led to homes, and the upper part of the pipes are vacant spaces, so communication with each home is possible. It is attracting attention as an important infrastructure for the FTTH (Fiber To The Home) project that draws in cables.

  On the other hand, as a communication cable, an optical fiber cable, which has much better performance than a metal cable used so far, has been attracting attention. An optical fiber cable is made of thin fibers of glass or plastic, uses light as an information carrier, and sends a signal obtained by digitalizing information such as sound and video (1, 0 signal). Compared to metal cables, optical fiber cables are superior in broadband, low loss, immunity to electromagnetic waves, light weight, small size, safety, and confidentiality, and can flow information amounts from tens to hundreds of times. It has excellent characteristics as a communication medium.

  In the FTTH project, which is a system using optical fiber cables, it is considered that each house is divided into 200 to 500 small blocks and controlled. In each block, public facilities such as public halls and dispatch stations are used as communication bases. It is assumed that an optical fiber cable will be laid to each house.

  When laying optical fiber cables in each house using sewer pipes, the optical fiber cables pass through the branch pipes from the sewer main pipe and from the branch pipes at the end of the branch pipes (sewage tanks, in residential land or on the road) Is led to each house by digging underground.

  In a manhole or the like that lays about 24 to 200 cores or branch cables (communication cables) from the communication base into the underground pipe main and connects the underground pipes to each other, Branch cables (communication cables) of about 2 to 4 cores (more than the housing complex) for laying to each house. And, there is a method of laying cables from manholes and so on to each house from the main pipe through branch pipes, and it is planned to lay communication cables in all houses, but in reality it is an empty house or for the time being Some homes do not want to be laid. Therefore, the situation where the laying time shifts by each house arises.

  In view of such a background, when laying the communication cable in the underground conduit so that the laying time of the communication cable can be shifted by each house, laying a call line that can be replaced in advance with the communication cable, When the incoming line becomes necessary, the call line is replaced with a communication cable.

Japanese Patent Application Laid-Open No. H10-228707 discloses a connection portion for replacing the call line with a communication cable and laying the communication cable. This is a step that occurs in the sheath of the connecting portion between the fixing tool and the communication cable by removing the sheath at the tip of the communication cable, exposing the tension member, and fitting and fixing the fixing tool to the tip of the tension member. Is formed into a tapered shape by applying heat to the sheath of the communication cable, and the sheath is covered to a part of the fixture. Next, the taper is wound with a tape from the sheath portion of the communication cable to the distal end of the fixture so that the diameter is smaller than the diameter of the communication cable. When the connection part of the communication cable having such a configuration is connected to the call line and the call line is pulled out, the call line can be replaced with the communication cable.
JP 2000-292667 A

  However, when the call line and the communication cable are exchanged by such a connection portion, the fixture attached to the communication cable is not bendable, and if there is a curved pipe in the communication cable's incoming line, the incoming line becomes difficult. . In addition, even when a fixture or the like is caught during the work of replacing the call line with the communication cable, the reverse return is impossible because the shape is tapered.

  In consideration of the above-described problems, the present invention is inserted into a main pipe in an underground conduit and a plurality of branch pipes connected to the main pipe into a guide pipe serving as a communication cable incoming path. When the laying of the communication cable is necessary, the communication cable is securely inserted, and the cable can be inserted even under the condition that the guide tube has a small diameter and is bent. It is an object of the present invention to provide a method for connecting to a communication cable using a call wire that can be returned in any case.

The method for connecting a call wire and a communication cable according to claim 1 for solving the above-mentioned problem is laid in an underground conduit where a branch pipe branches off from the main pipe and intersects with the longitudinal direction thereof. A guide tube having a plurality of branch holes opened in a direction is inserted to replace a communication cable covered with a resin layer, and one end of the guide tube is connected to the outside of the guide tube through one of the plurality of branch holes. Take out and pull out to the end of the branch pipe, connect a communication cable to the other end, and pull the one end from the end of the branch pipe, and can be laid in the branch pipe through the communication cable in the guide pipe The nominal line is substantially the same as the outer diameter of the communication cable, and is composed of a round braid having a core thread inserted inside and a plurality of leather threads outside. The above After unraveling the thread at the tip of the wire and removing a part of the unraveled thread, a part of the core thread is removed to form a cavity inside the nominal line, and the communication By removing the resin layer at the end of the cable, a protrusion having the same diameter as the outer diameter of the core yarn is formed, and the protrusion of the cable is inserted into the cavity before the resin of the communication cable. The remaining leather is wrapped around the outer surface of the layer and bonded.
According to such a method, it is possible to connect the call wire and the communication cable without changing the outer diameter of the communication cable by reducing the amount of leather wound around the outer surface of the end of the communication cable.

Further, the connection portion between the call line and the communication cable is brought into the fitted state, whereby the call line and the communication cable can be more firmly connected.
The call line connected to the communication cable in this way can insert the communication cable into the guide tube, and since it is a braid, it can be firmly connected by tightening the communication cable when pulled. Furthermore, the tension applied to the nominal wire when the nominal wire and the communication cable are exchanged can be handled by the entire yarn, and since it has flexibility due to the nature of the braided structure, the strength is high even with a small diameter. There is a feature that it is easy to bend when a communication cable is inserted. In addition, there is almost no difference between the call line and the communication cable, and it can be moved in the forward and reverse directions, so that if the call line is replaced with the communication cable, it can be reversed, and the call line communicates again It can be easily replaced with a cable.

The connection method of the call wire and the communication cable according to claim 2 is the method of connecting the call wire and the communication cable according to claim 1, wherein a total of 8 or more round threads of the call wire are assembled and the adjacent leathers in the same direction. The thread thickness is different by more than twice, and the tip part of the thread that is almost the same as the outer diameter of the communication cable is unwound, the thick thread is removed, and only the thin thread is communicated. It is wound around the outer surface of the end of the cable and joined.
According to such a method, the leather thread wound around the outer surface of the end portion of the communication cable is only a thin line, the step difference of the connection portion can be minimized, and the call line can be replaced with the communication cable more smoothly.

  Hereinafter, an example of an embodiment of the present invention will be described with reference to the drawings. In the following description, the underground pipe line is described as a sewer pipe, but the pipe line system and pipe type are not particularly limited.

  FIG. 1 shows an underground conduit 1 provided between manholes 2 and 3 for laying communication cables. Other manholes may be provided between the manholes 2 and 3, and the present invention can be similarly applied even if the manhole is a communication base. In FIG. 1, a plurality of branch pipes A, B,... J corresponding to households a, b,.

  FIG. 2 shows a cross-sectional view taken along the line II of FIG. In FIG. 2, reference numeral 1 denotes a main sewer pipe, which is piped between a manhole 2 and another manhole 3. From the upper side of the main pipe 1, branch pipes 4 and 5 (corresponding to any of A to J in FIG. 1) branch at branch pipe ports 6 and 7, and the branch pipes 4 and 5 are connected to each household (see FIG. 1) (corresponding to a, b,... J in FIG. 1).

  In general, the main pipe 1 is laid at a depth of several meters along the road, and branch pipe ports 6 and 7 are formed on the oblique upper side of the main pipe 1. 7 are connected to branch pipes 8 and 9.

  As shown in FIG. 1, the underground pipe in the present embodiment includes branch pipes A to J from the main pipe 1, a, b, c, d, e on the upper side of the figure, f on the lower side of the figure, There are a total of 10 branches toward each home located at g, h, i, j. In this embodiment, communication cables are laid only in three houses located at b, e, and j, and other houses located at a, c, d, f, g, h, and i. A description will be given assuming that no communication cable is installed.

  First, using a TV camera or the like in the main pipe 1, the distance between the manholes 2 and 3, the distance from the manhole 2 to the branch ports 6 and 7 of the branch pipes 4 and 5 in the main pipe 1, the branch pipe 4 , 5 to the branch pipe rods 8, 9 and the depth of the branch pipe rods 8, 9 are accurately measured (see FIG. 2). After conducting the survey as described above, a guide tube for storing the communication cable is prepared.

  Here, in the present embodiment, for the houses a, c, d, f, g, h, i in which no communication cable is laid, a call line 17 for easily laying a communication cable in the future is provided. The main pipe 1 is laid near each branch pipe port or up to each branch pipe rod.

  An example of the guide tube used in the present invention is shown in FIG. The shape of the guide tube 11 shown in FIG. 3 is particularly suitable in the present invention. The guide tube 11 is preferably made of a resin such as polyethylene because of its light weight and chemical resistance, but other materials can be selected depending on the type of underground conduit.

  As shown in FIG. 3, the guide tube 11 is a double-structured pipe composed of an outer tube 12 and an inner tube 14 having a partition plate 13 extending in the left and right direction. The inside of the inner pipe 14 serves as a passage for passing a trunk line of a communication cable passing through the main pipe 1 or a trunk line for the trunk line. Two partition plates 13 a, 13 b, 13 c, and 13 d that extend to the left and right are attached to both sides of the outer periphery of the inner tube 14, and partition the space between the outer tube 12 and the inner tube 14 in the vertical direction. The outer tube 12 is a hollow tube having a substantially elliptical cross section so that a plurality of communication cables or call wires can be arranged in parallel. A tension member 15 for installing the guide tube 11 on the upper portion of the main tube 1 is inserted into the guide tube 11.

  Six spaces surrounded by the partition plates 13a, 13b, 13c, and 13d serve as passages for passing the communication cable (retraction cable) 16 or the call wire 17. In addition, it is preferable to use the thing with the thickness with which communication cable 16 and nominal line 17 are substantially equal. As a result, when the call line 17 is replaced with the communication cable 16, the communication cable 16 is not displaced. Further, since an excessive pulling force does not act when the communication cable 16 is pulled, disconnection of the communication cable 16 can be prevented.

  The communication cable 16 has a stainless steel tube as a tension material inside, a four-core optical fiber is passed through the stainless steel tube, and a cable with a thickness of about 5 mm whose outer surface is coated with polyethylene resin. In this embodiment, it can be used suitably. The communication cable 16 can be a two-core type or other types in addition to the four-core type.

  As shown in FIG. 4, the nominal line 17 has a core thread 33 inserted therein and is formed of a round braid 30 made of leather thread, and has an outer diameter substantially equal to the outer diameter of the communication cable 16. The outside of the round braid 30 is composed of a leather 31 and a leather 32. The leather 31 is twisted by twisting two filaments 760T made of polypropylene. 4 pieces that are made by aligning 6 strands and using 4 strands of polypropylene 760T that are made by drawing and twisting two strands of polypropylene 760T. In this embodiment, the thread 31 and the skin thread 32 are combined into the round punched structure 30 so that the thicknesses thereof are different by a factor of two or more. In this way, the round punching assembly 30 composed of the leather 31 and the leather 32 having a thickness that is twice or more different from each other has a concavo-convex surface and is used for picking up the nominal line 17 when replacing the communication cable 16. The surface contact area of 17 is reduced, and the contact resistance with the guide tube is reduced. The round braid 30 of the call wire 17 can handle the tension applied to the call wire 17 when the call wire 17 and the communication cable 16 are replaced by the whole leather.

  Moreover, the leather thread which comprises the round punching thing 30 is assembled by 8 or more, Preferably, it is assembled by 8, 12, 16 pieces. If the number of leather yarns is 8 or less, it cannot be manufactured as a round braided product, and only one type of leather yarn can be used, so that the core yarn cannot be inserted and the surface cannot be made uneven. The effect of the call line 17 in the embodiment is diminished. On the other hand, when the number is 18 or more, the unevenness on the upper surface of the nominal line 17 becomes too smooth, and conversely, the contact resistance increases and the manufacturing speed is also slowed and expensive.

  The material of the leather thread 31 and the leather thread 32 includes polyethylene, polypropylene, nylon, and the like, and any of them can be used. Also, the same material can be used for the core yarn 33. In this embodiment, the core yarn 33 is made by aligning six filaments 3300T made of polypropylene. The round punched article 30 in which the core yarn 33 is inserted does not decrease in diameter even when tension is applied, and the diameter of the round punched article 30 does not decrease even during the replacement work with the communication cable 16. The same diameter can be maintained. In addition, even under conditions where the guide tube has a small diameter and is bent, it has flexibility due to the nature of the braided tissue, and since it has a small strength, it has high strength and is easy to bend. The call line 17 and the communication cable 16 can be replaced. In addition, it is not limited to the round punched product 30 in which the core yarn 33 is inside, and can be used even if the core yarn 33 is not in the round punched product 30.

  The height of each passage of the communication cable 16 and the call line 17 partitioned by the outer pipe 12 of the guide pipe 11 and the partition plate 13 of the space of the inner pipe 14 is twice the outer diameter of the communication cable 16 and the call line 17. It is lower. By adopting such dimensions, the communication cable 16 or the call wire 17 having substantially the same diameter as the communication cable 16 does not cross over the adjacent communication cable when entering the guide tube 11, The communication cable 16 is not entangled inside the guide tube and excessive tension is applied, or the communication cable 16 is not cut beyond the allowable bending radius. In addition, the structure in which a plurality of communication cables 16 can be connected in parallel in the width direction can suppress the height when installed in the main pipe 1 as much as possible. For example, an empty space in the upper part such as a sewer pipe or a rainwater pipe. If there is, there is no hindrance to the original function of the underground conduit by installing it at that location.

  As shown in FIG. 5, the communication cable 16 is connected to the guide pipe 11 at a position about 1 m from the position at each branch pipe port 6, 7 with the guide pipe 11 being pulled into the main pipe 1. A branch hole 18 is provided for drawing the nominal line 17 from the guide tube 11 to the outside. The branch holes 18 are opened on both side surfaces of the guide tube 11 at positions corresponding to the length from the manhole 2 to each branch tube port (within a range of about 1 m in the front and rear directions) with one end of the guide tube 11 as a base point. ing. The branch hole 18 is preferably formed in advance in a factory or the like based on the investigation result in the underground pipeline. Since the fluid from the branch pipe may flow into the branch hole 18 at the position of the branch hole 18, it is preferable to attach a branch tool 19 covering the branch hole 18 to the guide pipe 11. A branch guide pipe 20 is installed in the branch pipes 4 and 5 and protects the communication cable 16.

  A member 21 used to pull out the branching guide tube 20 to the branch pipe rods 8 and 9 is attached to the tip of the branching guide tube 20 so as not to be removable. Various shapes such as a hook shape and a ring shape can be adopted as the shape of these callers 21. Moreover, as shown in FIG. 5, you may process into the shape 22 which can be directly hooked or grabbed the front-end | tip of the call wire 17. As shown in FIG.

  With the configuration as described above, the branch line B, E, J that leads to the homes b, e, j for which the communication cable 16 is desired to be installed at the same time as the main pipe 1 and the guide pipe 11 is connected to the call line 17. And the communication cable 16 are replaced and installed, and the call line 17 is stopped for other households that do not wish to install the communication cables 16 of a, c, d, f, g, h, i. In the future, when one of the households a, c, d, f, g, h, i that wishes to install the communication cable 16 appears, each branch pipe A, C, D, F, G, H The communication cable 16 can be laid by replacing the call line 17 laid up to the branch pipe port of the I, I or the branch pipe end which is the end of the branch pipe with the communication cable 16.

  When the communication cable 16 is replaced, the communication cable 16 is connected to one end of a call line 17 laid on a branch pipe in a home where the communication cable 16 located on the manhole 2 side is desired. As a method for connecting the communication cable 16 and the nominal line 17, the outer surface of the communication cable 16 covered with polyethylene is peeled off from one end of the communication cable 16 to a position of 60 mm with a cutter knife or the like, and the stainless steel tube in the communication cable is peeled off. put out. The tip of the exposed stainless steel tube is rounded with a file or the like. The reason why the tip of the stainless steel tube is rounded is that when the tip of the stainless steel tube is inserted into the round wire assembly of the nominal wire 17 or when the nominal wire 17 is replaced with the communication cable 16 after the insertion. There is a possibility that the skin of the braided product 30 and the tip of the stainless steel tube rub against each other and the leather of the round braided product 30 may be worn out. Next, the hole at the tip of the stainless steel tube is closed with an adhesive or the like, and waterproofing is performed so that water or the like does not enter the stainless steel tube.

  The dirt on one end of the nominal line 17 on the manhole 2 side to be replaced with the communication cable 16 is wiped clean, and if it is wet, it is dried. After winding the vinyl tape around 50 mm from one end of the nominal line 17, only four threads 32 of the round braid 30 of the nominal line 17 to the vinyl tape part are unwound and the leather to the base of the vinyl tape Four of the yarns 31 and the core yarn 33 are cut with scissors or the like, and only the core yarn 33 is extracted 80 mm from the tip of the round punched article 30 and cut with scissors or the like.

  Next, the stainless steel tube having the rounded tip end of the communication cable 16 and the tip end portion of the cut core yarn 33 are pushed together into the round braided article of the call wire 17 so as to abut each other. After pushing the stainless steel tube about 30mm into the round braid, apply instantaneous adhesive on the outer surface of the remaining stainless steel pipe 30mm and insert it into the round braid until the stainless steel pipe of the communication cable 16 is not visible. The communication cable 16 and the call wire 17 are dried and bonded for 5 minutes. Thus, it becomes possible to insert the stainless steel tube of the communication cable 16 into the cavity formed by removing the core yarn 33 inside the nominal line, and the stronger connection between the nominal line 17 and the communication cable 16 becomes possible. Further, in the portion where the core yarn 33 of the nominal wire 17 remains, even if tension is applied to the nominal wire 17, the diameter of the round braid 30 is not reduced, and the same diameter as that of the communication cable 16 is maintained. No difference in level. In addition, even in the case of a round punched structure in which the core yarn is not inserted into the inside of the nominal line, the communication cable can be inserted into the round punched structure and the nominal line is pulled because it is a braided article. Sometimes a tight connection is possible by tightening the communication cable.

  After the communication cable 16 and the call wire 17 are bonded, an instantaneous adhesive is applied to the surface of the resin layer of the communication cable 16 from the boundary between the round braid 30 of the call wire 17 and the communication cable 16 to a position of 30 mm on the communication cable side. It is coated and wound with four uncut leather threads 32 of the round punched product 30, dried for 5 minutes and bonded. Thus, by winding and bonding four uncut leather threads 32 of the round braid 30 on the surface of the resin layer of the communication cable 16, the outer diameter of the communication cable 16 is hardly changed and the nominal line is changed. 17 and the communication cable 16 can be connected, the level difference in the connection portion between the call line 17 and the communication cable 16 can be minimized, and the call line 17 can be replaced with the communication cable 16 more smoothly. Become.

  In addition, it is not limited to inserting the stainless steel tube of the communication cable 16 into the round braided article of the call line 17, after unraveling the call line 17 and removing a part of the unraveled leather, It is also possible to wind and bond the remaining yarn in a state in which the round braid 30 of the nominal line 17 and the communication cable 16 are abutted to each other to the outer surface of the end of the communication cable 16. In this way, the call wire 17 and the communication cable 16 can be connected without changing the outer diameter of the communication cable 16 by removing a part of the leather thread.

Remove the vinyl tape wound around 50 mm from one end of the round wire assembly 30 of the nominal wire 17 on the manhole 2 side, and round the braid from the boundary between the round wire assembly 30 of the nominal wire 17 and the communication cable 16. The adhesive is applied to the outer periphery of the round braid 30 positioned 60 mm on the side, that is, at the tip of the stainless steel tube of the communication cable 16 inserted into the round braid, and dried for 5 minutes. By this work, the filaments of the thread of the round punched structure 30 are adhesively bonded so that the stainless steel tube of the communication cable 16 does not protrude from the round punched structure. The instant adhesives used so far are preferable in terms of work because the bonding time is short, but between the filaments of the round punched article 30 and between the filaments of the round punched article 30 and the stainless steel tube of the communication cable 16. Any kind of adhesive can be used as long as the thread of the round punched article 30 and the resin layer of the communication cable 16 can be bonded.

  FIG. 6 is a schematic diagram showing a connection state between the call wire and the communication cable. The connection state as shown in FIG. 6 is obtained by the above connection method, and the outer diameter of the communication cable 16 is almost reduced. The call line 17 and the communication cable 16 can be connected without being changed.

  With such a connection method, the call wire 17 and the communication cable 16 are connected, and the call wire 17 is pulled from the end of the branch pipe of the home where the communication cable 16 is desired to be laid, whereby the call wire 17 is connected to the communication cable 16. The communication cable 16 can be laid.

  As described above, according to the present invention, when it is necessary to lay a communication cable, it is possible to simply connect the call line and the communication cable and to lay the communication cable, and the guide tube has a small diameter. In addition, the communication cable can be inserted even under bending conditions. In addition, even if the call line is replaced with a communication cable, there is an effect that it can be reversed and the call line can be easily replaced with the communication cable again.

It is the figure which showed typically an example of arrangement | positioning of the underground conduit which concerns on this invention. It is a figure which shows the II sectional view taken on the line in FIG. 1 is a cross-sectional perspective view of an embodiment of a guide tube for laying a communication cable in an underground conduit according to the present invention. It is a schematic block diagram of the call line which concerns on this invention. It is a perspective view of one example of embodiment which shows the composition of the guide pipe for laying the communication cable in the underground pipe line concerning the present invention. It is the schematic which shows the connection state of the calling line and communication cable which concern on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Main pipe 2 Manhole 3 Manhole 4,5 Branch pipe 6,7 Branch pipe port 8,9 Branch pipe rod 11 Guide pipe 12 Outer pipe 13 Partition plate 14 Inner pipe 15 Tension member 16 Communication cable 17 Nominal line 18 Branch hole 19 Branch Tool 20 Guide pipe for branching 21 Girder 30 Round punched assembly 31 Leather thread (thick thread)
32 Leather thread (fine thread)
33 core yarn

Claims (2)

A communication cable coated with a resin layer on a guide pipe that is laid in an underground conduit where a branch pipe branches from the main pipe and that has a plurality of branch holes opened in a direction intersecting the longitudinal direction thereof; It is inserted for replacement, and one end is taken out of the guide tube through one of the plurality of branch holes and pulled out to the end of the branch tube, and a communication cable is connected to the other end, from the end of the branch tube A method of connecting a communication line and a nominal line that can be laid in a branch pipe through a communication cable in a guide pipe by pulling the one end,
The nominal line is substantially the same as the outer diameter of the communication cable, and is constituted by a round braid having a core thread inserted inside and a plurality of leather threads on the outer side. After unraveling and removing a part of the unraveled leather thread, a part of the core thread is removed to form a cavity inside the nominal line, and the end of the communication cable By removing the resin layer, a protruding portion having a diameter substantially the same as the outer diameter of the core yarn is formed, and the protruding portion is inserted into the hollow portion and then the remaining surface on the outer surface of the resin layer of the communication cable. A method of connecting a communication line and a nominal line that is wrapped around and joined with leather. A total of 8 or more round threads of the nominal wire are assembled, the thicknesses of the adjacent threads in the same direction are different from each other by more than twice, and the tip is the outer diameter of the communication cable. 3. The call wire and the communication cable according to claim 2, wherein the substantially same thread is unwound, the thick thread is removed from the unraveled thread, and only the thin thread is wound around the outer surface of the end portion of the communication cable. Connection method.

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