JP4621727B2 - Drop optical fiber traction tool - Google Patents

Description

  The present invention relates to a drop optical fiber laying tractor used when laying a drop optical fiber to a subscriber's house on an optical fiber cable (aerial optical cable) laid on a utility pole or the like.

  Conventionally, when laying an optical fiber cable with a long optical connector with a large diameter in a pipeline, a towing tool is attached to the cable end and the winch is pulled, but the cable end is damaged during cable laying work. Since it is easy, it is set as the structure which protects the optical connector extended from a cable edge part. The following various traction tools have been proposed as traction tools for pulling the optical fiber cable while protecting the optical connector.

  Patent Document 1 (Japanese Patent Application Laid-Open No. 2000-241692: “traction protection structure for optical cable termination with optical connector”) stores the optical fiber ribbon with an optical connector in a protective exterior body, The structure is such that a traction tool made of a wire sheathing body is arranged around the body, one end of the traction tool is fixed to the end of the optical cable, and the traction end (eye nut) is provided at the other end. The means for fixing one end of the traction tool to the end portion of the optical cable fixes the ring provided on the traction tool and the ring provided on the cable end portion to each other by fastening means such as bolts and nuts.

  The traction tool described in Patent Document 2 (Japanese Patent Laid-Open No. 1-200403: “Optical cable lead-in terminal structure”) houses an optical fiber with an optical connector in a flexible protective cylinder, and one end of the protective cylinder is connected to the optical cable. It is a structure in which a traction end (pooling eye) is attached to the other end with a binder fixed to the outer periphery of the end.

A traction tool described in Patent Document 3 (Japanese Patent Laid-Open No. 9-230186: “Terminal structure of optical fiber cable”) accommodates an optical fiber with a connector and a tension member in a flexible hollow tube, and the entire surrounding surface thereof. The traction block has a structure in which the tension member is fixed by a connecting block body fixed inside one end of the hollow tube and is fixed inside the other end of the hollow tube. It is the structure which provided the pulling end (annular body) in the body.
JP 2000-241692 A JP-A-1-204003 Japanese Patent Laid-Open No. 9-230186

  However, since the traction tool described in Patent Document 1 is pulled by dragging the inside of a pipeline with a large traction force, the traction tool has a solid, large, and complicated structure. Therefore, the assembly of the traction tool is not easy, and the work of disassembling it and taking out the optical connector after laying is complicated.

  Further, the traction tool described in Patent Document 2 and the traction tool described in Patent Document 3 have a firm, large, and complicated structure, and the assembly work and the disassembly work are both complicated.

  In addition, any of the traction tools described in Patent Documents 1 to 3 has a complicated means for fixing the traction tool to the optical fiber cable so that it can cope with a large traction force.

  In addition to this, in the case of a drop optical fiber (optical drop cable) that is dropped from a fiber optic cable (aerial optical cable) installed on a utility pole or the like to a subscriber's house, it is a thin cable of at most 1 to 2 cores, Since it is an aerial laying of about a meter, the required traction force is relatively small.

  Also, the protective structure of the optical connector does not need to be so strong as compared with a case where a long cable having a large diameter is pulled through the pipeline. It is required that the process of dismantling the traction tool after completion of the laying operation is also easy.

  The present invention has been made in order to solve the above-mentioned problems, and has a simple structure and a small size, and a drop light that is easy to assemble at the cable laying site and to be easily disassembled after the laying operation is completed. An object is to provide a fiber laying traction tool.

A drop optical fiber laying traction tool according to claim 1 of the present invention is attached to the tip of a drop optical fiber that is connected to an optical cable core in a closure provided in an aerial optical cable, and pulls the drop optical fiber. a traction tool for it, pre-attached optical connector for connection to the tip of the drop optical fiber, the tip portion of the drop optical fiber comprising the optical connector, which was housed in the body inside a tubular having a traction hook Yes,
The main body has a pulling hook attached to the distal end, a drop optical fiber insertion hole is formed at the proximal end, and is divided into a first main body and a second main body in the axial direction. An insertion hole for inserting a required length portion from the distal end of the support line cut from the distal end portion of the drop optical fiber from the distal end side to the proximal end side is formed inside the insertion hole, and the insertion hole includes the insertion hole. By folding back the support line into which the required length is inserted at the end on the entrance side of the insertion hole, the drop optical fiber connected to the support line is positioned in the insertion hole, and an optical fiber cut from the support line and The optical connector attached in advance to the tip of the optical connector is configured to be disposed in the first main body.

The drop optical fiber laying tractor according to claim 2 of the present invention is the drop optical fiber laying tractor according to claim 1 , wherein the first main body is attached to the tip and the traction hook is rotatable around the axis. The first main body and the second main body are formed in a tapered shape in which the proximal end side is gradually narrowed toward the insertion hole of the drop optical fiber, and a required length portion from the distal end of the support line An outlet-side end portion of the insertion hole for inserting the opening is opened in the tapered wall surface of the first main body.

The drop optical fiber laying traction tool according to claim 3 of the present invention is the drop optical fiber laying traction tool according to claim 1 or 2 , wherein the first main body and the second main body are at the tip and in the axial direction. A distal end engaging portion that engages with each other along the distal end, and a proximal end engaging portion that engages with the distal end engaging portion as a fulcrum on the proximal end side. Either one of the main body and the second main body is an engagement hole, and the other is an engagement protrusion that engages with the engagement hole, and the proximal-side engagement portion includes the first main body and the second main body. Any one of these is a pair of left and right engaging holes formed on both sides with respect to the divided surfaces, and the other is an engaging claw that engages with the engaging hole.

A drop optical fiber laying tractor according to claim 4 of the present invention is the drop optical fiber laying traction tool according to claim 3 , wherein the engagement protrusion is engaged with the engagement hole. When the claw is inserted into the engagement hole, the engagement claw is deformed inward from the left and right sides and then returned to the initial position, whereby the engagement claw is engaged with the engagement hole, and the engagement claw is When removing from the engagement hole, the engagement claw is detached from the engagement hole by pushing the engagement claw from the left and right sides to deform inward.

  As described above, the present invention is a traction tool for pulling a drop optical fiber attached to the tip of a drop optical fiber that is connected to an optical cable core in a closure provided in an aerial optical cable. An optical connector for connection is attached to the tip of the fiber in advance, and the tip of the drop optical fiber including this optical connector is housed inside a cylindrical body with a pulling hook, so the structure is extremely simple. And it is small.

  Embodiments of the present invention will be described with reference to the drawings.

  1 is a front view showing an embodiment of a traction tool for laying a drop optical fiber according to the present invention, FIG. 2 is a longitudinal front view, FIG. 3 is a plan view showing a state where an upper body is removed, and FIG. 4 is a drop optical fiber. It is a top view which shows the front-end | tip part.

  This drop optical fiber laying tool 10 is used when laying the drop optical fiber 1 to a subscriber's house on an optical fiber cable (aerial optical cable) laid on a utility pole or the like.

  That is, the drop optical fiber laying traction tool 10 is attached to the distal end of the drop optical fiber 1 that is connected to the optical cable core wire in a closure provided in the overhead optical cable and pulls the drop optical fiber 1. is there.

  Such a drop optical fiber 1 is an extremely thin cable having about 1 to 2 cores of an optical fiber 2, and as shown in FIG. 4, an optical fiber 2 and a support wire (hardened steel wire with coating) 3 Is a self-supporting type integrated by a part of the jacket.

  Therefore, the drop optical fiber laying traction tool 10 has a connection optical connector 5 attached to the tip of the drop optical fiber 1 in advance, and the tip of the drop optical fiber 1 including the optical connector 5 is attached to the cylindrical main body 11. Used inside.

  As shown in FIG. 1, the drop optical fiber laying traction tool 10 includes a cylindrical main body 11, and the cylindrical main body 11 is divided into a lower main body 20 and an upper main body 30 in the axial direction thereof. Yes.

  A pulling hook 12 is attached to the distal end (right end in the figure) of the cylindrical main body 11, and a drop optical fiber insertion hole 13 through which the drop optical fiber 1 is inserted is formed in the base end (left end in the figure). .

  As shown in FIGS. 2 and 3, the lower main body 20 extends along the axial direction of the cylindrical main body 11 at a position slightly deviated from the axial center of the cylindrical main body 11 in the interior following the drop optical fiber insertion hole 13. A support wire insertion hole 21 is formed.

  The support wire insertion hole 21 inserts a required length portion from the tip of the support wire 3 cut from the drop optical fiber 1 from the tip (right end in the drawing) side to the base end (left end in the drawing) side. To do. That is, the right end in the figure of the support wire insertion hole 21 is the insertion hole inlet end 21i, and the left end in the figure is the insertion hole outlet end 21o.

  Therefore, the tip of the support wire 3 is inserted into the support wire insertion hole 21 from the insertion hole inlet end 21i, and the insertion is terminated at a position where the tip reaches the insertion hole outlet end 21o. The support wire 3 substantially in the length from the insertion hole inlet end 21 i to the insertion hole outlet end 21 o can be inserted into the support wire insertion hole 21.

  Then, at the position where the support line 3 has been inserted into the support line insertion hole 21, the lower main body 20 is positioned approximately 180 with respect to the support line 3 extending outward from the support line insertion hole 21 with the insertion hole inlet end 21 i as a fulcrum. By bending the support wire 3, the support wire 3 is substantially folded at the insertion hole inlet end 21i.

  At this time, for example, a portion of a certain length (substantially the length from the insertion hole inlet end 21 i to the insertion hole outlet end 21 o) from the tip of the support line 3 is held in the hand without being inserted into the support line insertion hole 21. Compared to the case where the support body 3 is bent by approximately 180 °, it is very easy to hold the lower body 20 in which the same portion of the support wire 3 is inserted into the support wire insertion hole 21 and bend it by approximately 180 °.

  Thereby, the support line 3 extended outward from the support line insertion hole 21 can be positioned in the drop optical fiber insertion hole 13 together with the optical fiber 2. At this time, the optical connector 5 attached in advance to the tip of the optical fiber 2 is disposed in the lower main body 20 on the tip (right end in the drawing) side from the support wire insertion hole 21.

  Therefore, the traction force to the traction tool 10 for laying the drop optical fiber that pulls the traction hook 12 is supported by the support line 3 that is folded back at the insertion hole entrance end 21 i of the drop optical fiber 1. It does not act on the optical connector 5 attached in advance.

  Therefore, when the tip of the drop optical fiber 1 is cut as shown in FIG. 4 and the optical connector 5 is attached to the tip of the optical fiber 2 in advance, the cut length of the optical fiber 2 and the support wire 3 is shown in FIG. As shown in FIG. 3, when the support wire 3 has a required length necessary for insertion of the support wire insertion hole 21 and the optical connector 5 is disposed in the lower main body 20, the drop optical fiber insertion hole 13. It is preferable that the length of the drop optical fiber 1 that is not torn is long enough to be positioned.

  That is, when the optical connector 5 is disposed in the lower main body 20 as shown in FIG. 3 from the viewpoint that the traction force applied to the traction hook 12 is reliably supported by the support line 3 and does not act on the optical fiber 2, It is preferable that the split branch point between the fiber 2 and the support wire 3 is also disposed in the lower main body 20.

  FIG. 5 is an enlarged left side view of the drop optical fiber laying traction tool 10, FIG. 6 is an enlarged right side view with the traction hook omitted, and FIG. 7 shows a state where the lower main body and the upper main body are not attached. FIG. 8 is a front view showing a state in the middle of attachment / detachment between the lower main body and the upper main body.

  The lower body 20 includes a tow hook attachment hole 22 to which the tow hook 12 is attached at the tip. The tow hook 12 is rotatably attached around the axis of the drop optical fiber laying tow 10 by a tow hook mounting hole 22. Therefore, even if a rotational force around the axis acts on the tow hook 12 due to circumstances on the side to which the tow hook 12 is towed, only the tow hook 12 rotates according to the rotating force, so that the towing tool for laying a drop optical fiber is provided. It is possible not to exert a rotational force around the axis with respect to 10.

  As a result, twisting of the drop optical fiber 1 is not required during the construction of the drop optical fiber 1, and there is no danger of causing the worst situation such as disconnection of the optical fiber 1, and a stable and high quality construction is performed. be able to.

  Further, the tubular main body 11 of the drop optical fiber laying tool 10 is such that the lower main body 20 and the upper main body 30 are gradually narrowed toward the drop optical fiber insertion hole 13 on the base end (left end in FIGS. 7 and 8) side. It is formed in a tapered shape. The insertion hole outlet end 21 o of the support line insertion hole 21 is open to the tapered wall surface of the lower main body 20.

  The lower main body 20 has an engagement hole 25 formed at the tip (right end in FIGS. 7 and 8). On the other hand, the upper main body 30 has an engagement protrusion 35 formed at the tip (right end in FIGS. 7 and 8). By engaging the engagement protrusion 35 of the upper body 30 with the engagement hole 25 of the lower body 20 along the axial direction, the distal end of the lower body 20 and the distal end of the upper body 30 are engaged.

  The lower main body 20 has a pair of left and right engaging holes 26a and 26b formed on both sides with respect to the dividing surface of the lower main body 20 and the upper main body 30 on the base end (left end in FIGS. 7 and 8) side. Has been. On the other hand, the upper main body 30 is formed with a pair of left and right engaging claws 36a and 36b formed on both sides with respect to the dividing surface of the lower main body 20 and the upper main body 30 on the base end (left end in FIGS. 7 and 8) side. Has been.

  With the engagement protrusions 35 of the upper main body 30 engaged with the engagement holes 25 of the lower main body 20 along the axial direction, the engagement claws 36a and 36b of the upper main body 30 are engaged with the engagement holes 26a and 26b of the lower main body 20, respectively. The lower main body 20 and the upper main body 30 are integrated by overlapping the divided surfaces. That is, the lower main body 20 and the upper main body 30 are integrated to form the cylindrical main body 11.

  At that time, when engaging the engaging claws 36a, 36b of the upper main body 30 with the engaging holes 26a, 26b of the lower main body 20, according to inserting the engaging claws 36a, 36b into the lower main body 20, After the engaging claws 36a and 36b are deformed inward from the left and right sides, the engaging claws 36a and 36b reach the engaging holes 26a and 26b, and the deforming force is released to return to the initial position, thereby achieving the engagement.

  On the other hand, when the engaging claws 36a, 36b of the upper main body 30 are removed from the engaging holes 26a, 26b of the lower main body 20, the engaging claws 36a, 36b are pushed inward from the left and right sides to be deformed inward, thereby causing the engaging holes 26a. , 26b, and the engagement claws 36a, 36b are removed, and the engagement claws 36a, 36b are pulled out as they are, so that the removal is achieved.

  As described above, the drop optical fiber laying traction tool 10 has a very simple structure and is small in size, and therefore, an optical fiber cable (aerial optical cable) laid on a utility pole or the like is used as a drop optical fiber to a subscriber's house. It is very suitable for use when laying 1.

  The drop optical fiber laying traction tool 10 has a traction force support structure that reliably supports the traction force of the drop optical fiber laying traction tool 10 applied to the traction hook 12 by the support wire 3 without acting on the optical fiber 2. As a result, it is extremely simple, and as a result, the assembling of the traction tool at the cable laying site and the disassembly after the laying work can be performed very easily.

  In particular, the work of attaching the optical connector 5 to the tip of the optical fiber 2 by tearing the tip of the drop optical fiber 1 can be performed in advance, for example, in an office or the like. be able to.

  As a result, the optical connector 5 can be mounted in a gentle working environment compared to the cable laying site, so that stable and high-quality mounting can be realized, and at the same time, detailed and nervous work at the cable laying site Therefore, the work efficiency at the laying site can be improved.

  In the above embodiment, the engagement hole 25 is formed in the lower main body 20 and the engagement protrusion 35 is formed in the upper main body 30. However, the present invention is not limited to this. It is also possible to form an engagement hole in the upper main body 30.

  In the above-described embodiment, the engagement holes 26a and 26b are formed in the lower main body 20, and the engagement claws 36a and 36b are formed in the upper main body 30, but the present invention is not limited to this. It is also possible to form an engaging claw in the upper body 30 and to form an engaging hole in the upper body 30.

It is a front view which shows one Embodiment of the pull tool for drop optical fiber installation by this invention. It is a vertical front view of the pull optical fiber laying tool of FIG. It is a top view which shows the state which removed the upper main body of the pull tool for drop optical fiber installation of FIG. It is a top view which shows the front-end | tip part of a drop optical fiber. FIG. 3 is an enlarged left side view of the pull optical fiber laying tool of FIG. 1. FIG. 3 is an enlarged right side view in which a pulling hook of the drop optical fiber laying traction tool in FIG. 1 is omitted. It is an expansion | deployment front view which shows the state by which the lower main body and the upper main body are not mounted | worn. It is a front view which shows the state in the middle of attachment or detachment with a lower main body and an upper main body.

Explanation of symbols

1 drop optical fiber 2 optical fiber 3 support wire (coated hard steel wire)
5 Optical connector (connector for connection)
10 Drop optical fiber laying tool 11 Main body (tubular body)
12 Tow hook 13 Drop optical fiber insertion hole 20 Lower body (first body)
21 Support wire insertion hole 21i Insertion hole inlet end 21o Insertion hole outlet end 22 Tow hook attachment hole 25 Engagement holes 26a, 26b Engagement hole 30 Upper body (second body)
35 engaging protrusions 36a, 36b engaging claws

Claims (4)

At the time of laying a drop optical fiber that is connected to an optical cable core wire in a closure provided in an aerial optical cable, a traction tool that attaches to the tip of the drop optical fiber and pulls the drop optical fiber,
An optical connector for connection is attached in advance to the tip of the drop optical fiber, and the tip of the drop optical fiber including this optical connector is accommodated in a cylindrical main body provided with a pulling hook ,
The main body has a pulling hook attached to the distal end, an insertion hole for a drop optical fiber is formed at the proximal end, and is divided into a first main body and a second main body in the axial direction,
The first body is formed with an insertion hole for inserting a required length portion from the distal end of the support line cut from the distal end portion of the drop optical fiber from the distal end side to the proximal end side, following the insertion hole. The drop optical fiber connected to the support line is positioned in the insertion hole by folding back the support line having the required length inserted into the insertion hole at the entrance end of the insertion hole, and from the support line. A drop optical fiber laying tractor characterized in that the cut optical fiber and the optical connector attached in advance to the tip of the optical fiber can be arranged in the first main body. The first body is provided with a mounting hole at a distal end, and a pulling hook is rotatably mounted around an axis, and the first body and the second body are gradually proximally toward the insertion hole of the drop optical fiber. The outlet side end of the insertion hole into which the required length portion is inserted from the tip of the support line is open to the tapered wall surface of the first main body. The drop optical fiber laying tractor according to claim 1 . The first main body and the second main body include distal end engaging portions that engage with each other along the axial direction at the distal end, and proximal ends that engage with each other using the distal end engaging portion as a fulcrum on the proximal end side. A side engaging portion,
The tip engagement portion is an engagement protrusion in which one of the first main body and the second main body is an engagement hole and the other is engaged with the engagement hole,
In the base end side engaging portion, one of the first main body and the second main body is a pair of left and right engaging holes formed on both sides with respect to the split surface of the both, and the other is the engaging hole. The drop optical fiber laying traction tool according to claim 1 , wherein the traction tool is an engaging claw that engages with a drop optical fiber. When the engagement claw is inserted into the engagement hole with the engagement protrusion engaged with the engagement hole, the engagement claw is deformed inward from the left and right sides and then returned to the initial position. The engagement claw engages with the engagement hole;
When detaching the engaging pawl from the engaging hole, according to claim 3, wherein the engagement claw by deforming inwardly by pressing the engaging pawl from the left and right sides characterized by withdrawal through the engaging hole optical drop laying traction tool according to.

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