JP2008292803A - Terminal structure of cable and protection body - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a terminal structure of a cable of which the weight per unit length is small and the price per unit length is low, and in which tensile force or the like is easily prevented from acting on the branch or connection of the cables. <P>SOLUTION: The terminal branching structure of the optical cable includes a communication line and an anti-tensile force fabric disposed around the communication cable, a part of the anti-tensile force fabric is exposed from the terminal of the cable and a part of the exposed end side of the anti-tensile force fabric is integrated. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a terminal structure of a cable housing a communication line and a protector.

  Metal cables and optical cables are widely used for information transmission. In general cables, in order to prevent the communication lines such as metal wires and optical fibers from being damaged by the stress such as tension generated during laying, a central tension member is interposed in the cable, tensile strength fibers are accommodated, optical cables In this case, the optical fiber is dropped into the slot.

  Further, when the cable is fixed for connecting / branching, the communication line is prevented from being stressed by fixing the center tension member, the tensile fiber and the slot to a predetermined fixing portion.

Japanese Utility Model Publication No. 02-021601 JP-A-11-243636 Special Table 2004-526209

  However, a cable using a center tension member or a slot has a large outer diameter and weight and is expensive. On the other hand, although the above points are improved in the cable using the tensile strength fiber, the tensile strength fiber tends to be separated when the cable is fixed, and the handleability is poor.

  The present invention has been made in view of the above problems, and is a cable that can reduce the outer diameter and weight, and can reduce the price per unit length, and can be easily communicated when the cable is fixed. It aims at providing the terminal structure of the cable which can prevent that tension | tensile_strength etc. are added to a wire.

  In order to achieve the above object, a cable terminal structure according to the present invention is a cable terminal structure containing a communication line and a tensile fiber disposed around the communication line, and a part of the tensile fiber. Is exposed from the end of the cable, and a part of the exposed tensile strength fiber is integrated.

  In order to achieve the above object, the protector according to the present invention is a protector comprising two or more cylindrical parts and a coupling part that couples one end side of the cylindrical part, and the coupling part The surface is formed with a recess extending from one end to the other end.

  According to the cable terminal structure of the present invention, since the cable does not accommodate the center tension member or the slot, the outer diameter and the weight can be reduced, and the price per unit length can be reduced. it can.

  In addition, since the tensile strength member is formed by accommodating the tensile strength fiber and integrating a part of the exposed tensile strength fiber at the front end side, the tensile strength member is used instead of the central tension member or slot when the cable is fixed. Therefore, it is possible to easily prevent a tensile stress or the like from being applied to the communication line.

  The configuration of an embodiment of a cable terminal structure according to the present invention will be described in detail below with reference to FIGS. In this embodiment, an optical cable containing an optical fiber core wire is used as the communication line and cable. FIG. 1 is an example of a cross-sectional view of an optical cable 1 having a cable terminal structure according to the present invention. The optical cable 1 has a structure in which a cable core formed by arranging tensile strength fibers 3 around two optical fiber cores 2a and 2b and integrating them with a yarn or the like is covered with a sheath 4.

  In this embodiment, a so-called optical fiber cord in which a nylon core coated with a nylon resin on the outer periphery of a single-mode optical fiber is further coated with PVC as the optical fiber core 2 is used. Further, an aramid fiber was used as the tensile fiber 3 and polyethylene (PE) was used as the material of the sheath 4.

  Since the optical cable 1 of the present embodiment does not accommodate a central tension member made of steel wire, FRP, or the like, the weight per unit length is light and the price per unit length can be reduced. On the other hand, since the tensile strength fiber 3 is accommodated around the optical fiber core 2, the optical fiber core 2 can be prevented from being damaged by a tensile stress or the like during installation.

  The optical fiber core 2 is not limited to the above, and may be an optical fiber, an optical fiber housed in a tube, a Hytrel core, a tape core, or the like. Moreover, the tensile strength fiber 3 is not limited to the above, and may be glass fiber or carbon fiber. The material of the sheath 4 may be polyvinyl chloride (PVC) or a material mixed with a flame retardant.

  When the terminal is fixed to connect the optical cable 1 to another optical cable or the like, the sheath 4 on one end side of the optical cable 1 is cut with a sheath cutter or the like as shown in FIG. 2b and the tensile strength fiber 3 are exposed. Then, the exposed distal end side of the tensile strength fiber 3 is collected in the vicinity of the center portion of the optical cable 1, that is, in the vicinity of the extension line of the center line of the optical cable 1, and a part of the distal end side is collectively bundled and passed through the heat shrinkable tube 6. After that, the heat-shrinkable tube 6 is heated to form the tensile strength body portion 3 ′.

  Next, when the optical cable 1 provided with the strength member 3 ′ is connected to another optical cable using the optical connection box 20, the central tension member fixing part 21 of the optical connection box 20 is connected to the optical connection box 20 as shown in FIG. The tensile strength body portion 3 'is fixed. Thereafter, the optical fibers 2 are connected by fusion or the like. Since the connection of the optical fiber core wire is well known to those skilled in the art, the description thereof is omitted. Here, the cable on the right side of FIG. 3 is an optical cable containing a conventional center tension member, and the exposed center tension member 22 is fixed to the center tension member fixing portion 21 of the connection box 20.

  As described above, in the present embodiment, the tensile strength fibers 3 are bundled together and the distal end side is integrated to form the tensile strength body portion 3 ′, so that the tensile strength body portion 3 ′ is used as the central tension member of the conventional cable. It can be handled easily and is easy to handle.

  The exposed tensile strength fibers 3 are not necessarily collected near the center of the optical cable 1. Depending on the positional relationship between the optical connection box 20 and the optical cable 1, the optical fiber 2 may be collected and integrated in the direction where the stress is most applied.

  Next, a second embodiment will be described. In this embodiment, the optical cable 1 shown in FIG. 1 is used as the cable. An example of an external view of the cable terminal structure according to this embodiment is shown in FIG. In FIG. 4, SC connectors 7a and 7b are attached to the tips of the optical fiber cores 2a and 2b in this embodiment. Moreover, the sheath 4 removal part side of the optical fiber core wires 2a and 2b is accommodated in the protective tube 5. The tensile strength fibers 3 are divided into two substantially in the vicinity of the sheath 4 removal portion and are bundled together, and the two tensile strength fiber bundles 3 a and 3 b are drawn out to the distal end side through the outside of the protective tube 5. The pulled-out bundles 3a, 3b of the tensile strength fibers are partly integrated with an adhesive to form a tensile strength body portion 3 '. Also in this example, the bundles 3a and 3b of tensile strength fibers were gathered in the vicinity of the central portion of the optical cable 1 to form the tensile strength body portion 3 '. For connection to a connection box, an exchange, or the like, this strength member 3 'can be used in the same manner as a conventional center tension member. The bundles 3a and 3b of the tensile strength fibers do not necessarily have to be collected in the vicinity of the center portion of the optical cable 1, and the optical fiber 2 is most stressed depending on the positional relationship between the connection box, the exchanger, and the optical cable 1. Collect and integrate.

  In this embodiment, the protective tube 5 is fixed to the tensile strength fiber 3 and the sheath 4 of the optical cable 1 by covering the tensile strength fiber 3 with the heat shrinkable tube 6. When the protective tube 5 is not fixed to the optical cable 1, the optical fiber core wires 2a and 2b cannot be properly protected by moving the protective tube 5 toward the SC connector 7 or the like. The protection tube 5 may be fixed by using taping or an adhesive in addition to using the heat shrinkable tube 6. Furthermore, the protective tube 5 does not need to be fixed to both the tensile strength fiber 3 and the sheath 4, and the protective tube 5 and the tensile strength fiber 3 or the protective tube 5 and the sheath 4 may be bonded using an adhesive or the like. good.

  In this embodiment, since the optical fiber core wires 2a and 2b near the sheath 4 removal portion are covered with the protective tube 5, the optical fiber core wires 2a and 2b on the sheath 4 side even when the tensile strength body portion 3 'is pulled. Can be prevented from being tightened by the tensile strength fiber 3 to increase loss.

  FIG. 5 shows an example of the appearance of the protective tube 5 used in this embodiment. In this embodiment, the protective tube 5 is made of silicon resin. In FIG. 5, the protective tube 5 of the present embodiment includes two cylindrical bodies 51 a and 51 b having a circular cross section, and a part of one end side of the cylindrical bodies 51 a and 51 b is coupled by a coupling portion 53. . The cylindrical bodies 51a and 51b have appropriate flexibility, and in particular, the unconnected portions of the cylindrical bodies 51a and 51b (hereinafter referred to as open parts 54) can be freely changed in direction and the like independently of each other. Can do.

  In addition, a recess 52 extending from one end side to the other end side is formed in the coupling portion 53 of the protective tube 5. In this embodiment, the recess 52 is formed in a substantially triangular shape in which the end portion side of the protective tube 5 is formed wide and the width gradually decreases toward the open portion 54 side.

  The protective tube 5 is not limited to the above, and the protective tube 5 may be formed of a vinyl chloride resin or another hard body. When a four-core tape or the like is used as the optical fiber core wire 2, a cross-sectional square shape or the like may be used. Here, the length and the like of the cylindrical body 51 and the coupling portion 53 can be variously designed according to the laying conditions and structure of the optical cable 1. Moreover, the number of the cylindrical bodies 51 to be coupled can be set to various numbers depending on the number of cores of the optical fiber core 2 and the like. Further, the size and number of the recesses 52 of the protective tube 5 may be appropriate, and the recesses 52 may be omitted if the tensile strength fiber 3 can be integrated on the distal end side.

  Next, a method for forming the cable terminal structure according to this embodiment will be described with reference to FIG. In the case of forming the cable terminal structure according to the present embodiment, first, a heat shrinkable tube 6 having an inner diameter substantially equal to the outer diameter of the optical cable 1 is inserted from the terminal on the side where the optical cable 1 is processed. Thereafter, the sheath 4 near the end of the optical cable 1 is cut off using a sheath cutter or the like to expose the optical fiber core wires 2a and 2b and the tensile fiber 3. Next, when the tensile strength fiber 3 is divided into approximately two parts with a line connecting the two optical fiber cores 2a and 2b as a boundary line and bundled along a notch 52 (not shown), the tensile strength fibers 3 are temporarily fixed so as not to fall apart. It is set as bundles 3a and 3b of tensile strength fibers. At this time, some unnecessary tensile strength fibers 3 may be cut. Next, the two optical fiber core wires 2a and 2b are respectively inserted into the cylindrical bodies 51a and 51b of the protective tube 5 from the coupling portion 53 side, and the protective tube 5 is pushed into the vicinity of the end of the sheath 4 removal portion of the optical cable 1.

  When the protective tube 5 is moved to the vicinity of the end of the sheath 4 removal portion, the heat shrinkable tube 6 that was initially inserted into the optical cable 1 is placed on a part of the protective tube 5 from above the bundles 3a and 3b of the tensile fiber. Move in this way. Specifically, approximately half of the heat-shrinkable tube 6 is placed on the sheath 4 of the optical cable 1, and the remaining half is placed on the bundles 3 a and 3 b of tensile strength fibers and a part of the protective tube 5. Then, the sheath 4 of the optical cable 1, the bundles 3 a and 3 b of tensile strength fibers, and the protective tube 5 are integrated by heating the heat shrinkable tube 6.

  Next, the bundles 3a and 3b of the tensile strength fibers are pulled out to the tip side of the optical fiber 2 and bundled together, and integrated with an adhesive, a heat shrinkable tube, a yarn or the like to form the tensile strength body portion 3 '. Then, SC connectors 7a and 7b are attached to the tips of the optical fiber cores 2a and 2b taken out from the cylindrical bodies 51a and 51b, respectively.

  When connecting the optical cable with connector 1 having the tensile body portion 3 ′ formed as described above to an exchanger or the like, after fixing the tensile body portion 3 ′ to the exchanger, the connector plug of the exchanger or the like The SC connectors 7a and 7b attached to the tip end portion of the optical fiber core wire 2 extending from the optical cable 1 are fitted to each other. Here, the tensile strength body portion 3 ′ is fixed to the exchanger so that the tensile strength body portion 3 ′ is in a tension state when a tensile stress is generated in the optical cable 1. Therefore, even if a tensile stress is generated in the optical cable 1, the optical fiber core wire 2 and the SC connector 7 are not damaged by the tensile strength body portion 3 'receiving the stress.

  As described above, in this embodiment, the optical fiber core wires 2a and 2b in the vicinity of the sheath 4 removal portion are accommodated in the cylindrical body 51 of the protective tube 5, so that the optical fiber core wires 2a and 2b are tightened from the tensile strength fiber 3. Can prevent damage and the like. The protective tube 5 is easy to handle because a plurality of cylindrical bodies 51 are coupled by the coupling portion 53. In addition, since the substantially triangular recess 52 whose width gradually decreases toward the open portion 54 side is formed in the coupling portion 53 of the protective tube 5, the tensile strength body 3 can be easily stretched as long as the tensile strength fiber 3 extends along the recess 52. Part 3 ′ can be formed. Since the strength member 3 'can be handled in the same manner as the center tension member, the optical fiber cores 2a and 2b are easily protected from stresses such as tension by fixing the strength member 3' to an exchanger or the like. be able to.

  Here, the optical connector attached to the optical fiber core wire 2 is not limited to the SC connector 7, and may be an FC connector, an SC2 connector, or the like. Further, when the optical fiber core 2 is a tape core, an MT connector or the like may be used. Further, it is not always necessary to attach a connector or the like to the optical fiber core 2. For connection to a connection box or the like, the optical fiber core 2 is connected after the tensile strength member 3 'is fixed to the fixing portion of the central tension member. What is necessary is just to carry out the fusion | fusion connection etc. with the optical fiber core wire of the side to perform.

  Next, a third embodiment will be described. An example of the cross section of the cable 1 according to the present embodiment is shown in FIG. 7, and an example of the appearance of the protective tube is shown in FIG. As shown in FIG. 7, in this embodiment, the optical cable 1 accommodates three four-core tapes 2 as communication lines. Other configurations are the same as those of the first and second embodiments.

  In FIG. 8, the protective tube 5 according to the present embodiment is a combined body of cylindrical bodies 51c to 51e formed of three cross-sectionally-shaped silicon resins, and one end side of each of the cylindrical bodies 51c to 51e is a connecting portion. 53. Further, at least one recess 52 extending in the longitudinal direction of the cylindrical body 51 is formed in the coupling portion 53. In the present embodiment, three recesses 52c to 52e are formed by forming recesses between adjacent cylindrical bodies. Also in the protective tube 5 according to this embodiment, as in the second embodiment, the recesses 52c to 52e are formed so that the end portion side of the protective tube 5 is wide and the width gradually decreases toward the open portion 54 side. It is formed in a triangle.

  FIG. 9 is an example of a perspective view of the terminal structure of the optical cable 1 according to the present embodiment. In FIG. 9, 4MT connectors 7c-e are attached to the tips of three four-core tapes 2c-e, respectively. In the present embodiment, the four-core tapes 2c to 2e are respectively covered with the cylindrical bodies 51c to 51e of the protective tube 5, and the cylindrical bodies 51c to 51e are inside the 4MT connectors 7c to 7e of the four-core tapes 2c to 2e. It extends to.

  On the other hand, the tensile strength fibers 3 are gathered in the closer recesses 52c to 52e, respectively, so that the bundles 3c to 3e of the three divided tensile fibers are divided into 4MT connectors 7c along the recesses 52c to 52e of the protective tube 5. It is pulled out to the e side. The bundles 3c to 3e of the drawn tensile strength fibers are integrated with an adhesive or the like to form a tensile strength body portion 3 '. Similarly to the second embodiment, a part of the coupling portion 53 of the protective tube 5 is fixed to the sheath 4 of the optical cable 1 and the tensile strength fiber 3 by the heat shrinkable tube 6.

  When the optical cable 1 provided with the tensile strength body portion 3 ′ according to the present embodiment is connected to an apparatus such as an exchanger, the tensile strength body portion 3 ′ is connected to the central tension member fixing portion of the exchanger as in the second embodiment. Then, the 4MT connectors 7c to 7e attached to the four-core tapes 2c to 2e are fitted into connector plugs such as exchangers. Here, the tensile strength body portion 3 ′ is fixed to the exchanger or the like so that the tensile strength body portion 3 ′ is in a tension state when a tensile stress is generated in the optical cable 1. Therefore, even when a tensile stress is generated in the optical cable 1, it is possible to avoid damage to the four-core tapes 2c to 2e and the MT connectors 7c to 7e due to the tensile strength body portion 3 'receiving the stress. Further, since the vicinity of the exposed four-core tapes 2c to 2e in the sheath 4 side is accommodated in the protective tube 5, even when the tensile strength body portion 3 'is pulled, it is located outside the four-core tapes 2c to 2e. It will not be damaged by being fastened to the tensile strength fibers 3 that are present.

  In this embodiment, the protective tube 5 can be applied as it is to a 4MT connector, and the number of work steps is not greatly increased from the conventional work steps.

  Next, a fourth embodiment will be described with reference to FIGS. 10 is an example of a cross-sectional view of the optical cable 1 used in this embodiment, FIG. 11 is an example of an external view of the protective tube 5 used in this embodiment, and FIG. 12 is an external view of the terminal structure of the optical cable 1 according to this embodiment. It is an example. In FIG. 10, the optical cable 1 accommodates six optical fiber cords 2 as communication lines. In FIG. 11, the protective tube 5 used in the present embodiment is a combined body of four cylindrical bodies 51f to 51i. In the present embodiment, two recesses 52 f and 52 g are formed in the coupling portion 53 of the protective tube 5. The recess 52g not appearing in FIG. 11 is formed in a shape substantially the same as the recess 52f on the opposite side of the recess 52f.

  Here, since the optical cable 1 accommodates the six optical fiber cores 2, in this embodiment, two optical fiber core wires 2 are respectively provided in the cylindrical body 51 f and the cylindrical body 51 h of the protective tube 5. Insert them one by one. Further, the tensile strength fiber 3 is substantially divided into two with respect to the two recesses 52f and 52g. In the present embodiment, the tensile strength fibers 3 are divided into approximately two by collecting them in one of the recesses 52f and 52g, whichever is closer.

  The terminal structure of the optical cable 1 according to the present embodiment will be described with reference to FIG. In FIG. 12, two optical fiber core wires 2 are accommodated in the cylindrical body 51f and the cylindrical body 51h of the protective tube 5, respectively. SC connectors 7 are respectively attached to the ends of the six optical fiber core wires 2 drawn out from the four cylindrical bodies 51f to 51i. The tensile strength fibers 3 are gathered in either one of the recesses 52f and 52g, so that the tensile strength fibers 3 are substantially divided into two and formed into tensile strength fiber bundles 3f and 3g. The bundles 3f and 3g of the two tensile strength fibers are pulled out to the SC connector 7 side, and the tensile strength body portion 3 'is formed by integrating the tip side with an adhesive or the like. Since the connection of the optical cable 1 provided with the strength member 3 'to the exchanger or the like is the same as in the second embodiment, the description thereof is omitted.

  In the present embodiment, since the two optical fiber core wires 2 are inserted into some of the cylindrical bodies 51f and 51h of the protective tube 5, the protective tube 5 can be made small. In addition, since the two hollows 52 are formed on the four cylindrical bodies and the tensile strength fiber 3 is divided into approximately two parts, the operation is simple compared to dividing into four parts. In addition, you may utilize arbitrary two hollows with respect to the protection tube 5 in which four hollows were formed. Here, the size, number, and the like of the recesses 52 may be appropriately determined according to the outer diameter of the cable.

  As described above, in the cable terminal structure according to the present invention, since none of the cables accommodates the central tension member or the slot, the weight per unit length is light and the cost per unit length is low. can do. In addition, since part of the tip side of the plurality of tensile strength fibers is integrated to form the tensile strength body portion 3 ′, the tensile strength body portion 3 ′ can be handled in the same manner as a conventional central tension member or the like. In addition, it is possible to prevent a tensile stress or the like from being applied to the communication line, and it is easy to handle.

  Furthermore, by using the protective tube 5, even when the tensile strength body portion 3 'is pulled, the communication line is not tightened by the tensile strength fiber 3 positioned outside the communication line, thereby causing an increase in loss or disconnection. The protective tube 5 is easy to handle because the plurality of cylindrical bodies 51 are coupled by the coupling portion 53. Further, when the substantially triangular recess 52 is formed in the joint portion 53 of the protective tube 5, the tensile strength fibers 3 can be easily bundled as long as the tensile strength fibers 3 are aligned with the recess 52. 'Can be easily formed.

  The cable 1 can take various other configurations as long as it accommodates the tensile fiber 3 instead of the center tension member or the slot. The communication line to be accommodated is not limited to the optical fiber core 2 but may be a metal core or the like. The type of communication line to be accommodated is not limited to one type, and may be a composite cable of a metal core and an optical fiber tape, for example. Furthermore, in the optical cable 1 that accommodates one two-core tape, it is also possible to apply to a terminal branch structure in which the two-core tape is branched one by one.

1 is a cross-sectional view of an optical cable according to a first embodiment of the present invention. 1 is an external view of a cable terminal according to a first embodiment of the present invention. The figure which shows the connection structure of the optical cable which concerns on the 1st Example of this invention. The external view of the terminal branch structure of the optical cable which concerns on 2nd Example of this invention. The external view of the protection tube which concerns on the 2nd Example of this invention. The figure for demonstrating the formation method of the terminal structure of the optical cable which concerns on 2nd Example of this invention. Sectional drawing of the optical cable which concerns on the 3rd Example of this invention. The external view of the protection tube which concerns on the 3rd Example of this invention. The external view of the terminal branch structure of the optical cable which concerns on 3rd Example of this invention. Sectional drawing of the optical cable which concerns on the 4th Example of this invention. The external view of the protection tube which concerns on the 4th Example of this invention. The external view of the terminal branch structure of the optical cable which concerns on the 4th Example of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Optical cable 2 Optical fiber core wire 3 Tensile fiber 3 'Tensile body part 4 Sheath 5 Protective tube 6 Heat shrinkable tube 7 Optical connector 20 Optical connection box 21 Central tension member fixing part 22 Central tension member 51 Cylindrical body 52 Depression 53 Joint part 54 Opening area

Claims (8)

A cable terminal structure containing a communication line and a tensile fiber disposed around the communication line,
A portion of the tensile fiber is exposed from the end of the cable;
A cable terminal structure, wherein a part of the exposed tensile strength fiber on the front end side is integrated. The cable terminal structure according to claim 1, wherein the exposed tensile strength fibers are collected and integrated in the vicinity of a central portion of the cable. A portion of the communication line is exposed from the end of the cable;
The cable terminal structure according to claim 1, further comprising a protector that accommodates at least a part of the exposed communication line. The protector is
At least two cylindrical portions for accommodating the communication lines;
A coupling portion for coupling one end sides of the cylindrical portion to each other;
A cable terminal structure according to claim 3. The cable terminal structure according to claim 4, wherein a recess extending from one end to the other end is formed on a surface of the coupling portion. The cable terminal structure according to any one of claims 1 to 5, wherein a connector is attached to one end of the communication line. The cable end structure according to claim 1, wherein the communication line is an optical fiber core. Two or more tubular parts;
A coupling part for coupling one end side of the cylindrical part;
A protector comprising:
The protector according to claim 1, wherein a recess extending from one end to the other end is formed on the surface of the coupling portion.

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