JP4208201B2 - Branch connection box for optical cables - Google Patents

Description

  The present invention relates to an optical cable branch connection including an optical connection portion between an optical fiber core wire drawn from a main cable and an optical fiber core wire of a drop cable and / or a branch cable and a core wire storage tray for storing the extra length of the core wire. Regarding the box.

In an optical fiber communication subscriber network, when a drop cable from a trunk cable to a subscriber is pulled down, an optical closure called a drop closure is used. As schematically shown in FIG. 14, this type of optical closure 6 includes a core wire storage tray 4 in a watertight closure sleeve 5. The optical fiber storage tray 4 accommodates the optical connection portion 7 between the optical fiber core wire 1a which is an operation line drawn from the main cable 1 which is a trunk cable and the optical fiber core wire 2a of the drop cable 2, and the extra length of the core wire. In addition, an unlined core wire 1b is housed for use in drawing into a future subscriber.
The main cable 1 has a structure in which optical fiber cores 1a and 1b are accommodated in the spiral groove of the slot rod 1d having a spiral groove (not shown) on the outer periphery. In the illustrated example, the core rod 1d is cut without cutting the slot rod 1d. It is a core wire connection form for performing line connection.

  Conventionally, as shown in the figure, the unwired core wire 1b is placed in an unwired core holder 8 which is a nylon bag and accommodated in an extra length storage portion in the core wire storage tray 4.

  In the conventional optical closure 6, as described above, the unwired core wire 1b is put in the unwired core wire holder 8 and accommodated in the extra length storage portion in the core wire storage tray 4, so that the core wire storage tray 4 The operation line core 1a and the non-line core 1b are mixed. For this reason, when the unwired core wire 1b is connected to the drop cable as the operation line, there is a risk of touching the operation line core wire 1a during the operation of taking out the unwired core wire 1b from the core wire storage tray 4. There was a risk of communication failure.

  The present invention has been made to solve the above-mentioned conventional drawbacks, and there is no risk of touching the operation line core wire when the unwired core line is taken out from the core wire storage tray, which may cause unnecessary trouble on the operation line. An object of the present invention is to provide a branch connection box for an optical cable without any problem.

The present invention that solves the above-described problems includes an optical connection between the optical fiber core drawn from the main cable and the optical fiber core of the drop cable and / or the branch cable, and a core storage tray that stores the extra length of the core. Branch junction box for optical cable,
The unwired core wire drawn from the main cable for future operation is accommodated in a tube made of flexible resin, and the unwired core wire accommodating portion for accommodating the unwired core wire together with the tube is accommodated in the core wire. It is provided on the outer surface of the tray.

  A second aspect of the present invention is the optical cable branch connection box according to the first aspect, wherein the unlined core wire accommodating portion is a groove provided along the side surface in the width direction of the core wire accommodating tray.

  According to a third aspect of the present invention, in the branch connection box for optical cables according to the second aspect, the groove is bent upward at the side wall in the width direction of the core wire storage tray and the side edge in the width direction of the tray base made of metal plate. And formed by a wall portion.

  According to a fourth aspect of the present invention, in the optical cable branch connection box according to the second aspect, the groove is formed by integral molding with a plastic core wire storage tray.

  According to the present invention, since the unwired core wire is accommodated in the tube made of the flexible resin and disposed on the outer surface of the core wire storage tray, the unwired core wire is not touched without touching the operation line core wire. The wire can be taken out from the core wire storage tray, and there is no fear of causing unnecessary trouble on the operation line.

  Hereinafter, an optical cable branch connection box embodying the present invention will be described with reference to the drawings.

  FIG. 1 is a front view showing an internal structure of an optical cable branch connection box 11 according to an embodiment of the present invention, FIG. 2 is a plan view thereof, and FIG. 3 is an enlarged left side view of a main part of FIG. In these figures, 12 is a connecting rod. A cable gripping bracket 13, a tension member gripping bracket 14, and a drop cable gripping bracket 15 are fixed to both ends of the connecting rod 12 with screws. A horizontal arm 17 is fixed to the cable gripping bracket 13, and a suspension bracket 16 is fixed to the arm 17, and is suspended by a messenger wire (support wire) 18 by the suspension bracket 16.

  The above-described closure sleeve 19 that covers each part in a waterproof state is a plastic molded product, and has a split structure in which the lower part can be flattened horizontally around the upper hinge part in FIG. 3, and the engagement by the claw 19a and the locking part 19b. It is designed to be closed with a stop structure. End plates 20 are attached to the openings at both ends of the closure sleeve 19 so as to be in close contact with the opening edge and waterproof. The end face plate 20 has a split structure in which the lower part can be flattened horizontally around the upper hinge part. When the arm 17, the main cable 1, and the branch cable 3 are passed through, the arm insertion hole 21 and the main cable insertion hole 22 respectively. The portion that becomes the branch cable insertion hole 23 is thin. The drop cable insertion hole 24 is a through hole different from the split surface, and a large number are provided. Although details of the end face plate 20 are omitted, for example, a rubber cover is covered with a plastic cover.

A plastic core wire storage tray 25 is attached to the connecting rod 12. As shown in FIGS. 4 to 7, the core wire storage tray 25 is fixed to a metal plate tray base 27 with screws 28, and this tray base 27 is connected to the connecting rod 12 via a hinge 29 in FIG. It is attached so that it can rotate up and down like a. The tray base fixing pin 31 is slidably provided on the tray base 27, and the tray base fixing pin 31 is installed in a horizontal state by fitting into the locking hole 12a of the connecting rod 12 as shown in FIG. . FIG. 5 shows a state in which the tray base fixing pin 31 is pulled, and FIG. 6 shows a state in which the core wire storage tray 25 is turned up around the hinge 29. When it is necessary to work below the core wire storage tray 25, the core wire storage tray 25 is raised as shown in FIG. 5 to 7, reference numeral 26 denotes a tray fixing band, which is also used to hold the core wire storage tray 25 in the raised state as shown in FIG. FIG. 6 shows a state in which the main cable 1 is fastened and fixed to the connecting rod 12 with a binding band 32.
In the embodiment, the core wire storage tray 25 is one stage, but a plurality of stages may be stacked. The core wire storage tray 25 is provided with hinges 30 at the upper and lower portions. When a plurality of stacks are stacked, the upper and lower core wire storage trays 25 are connected to each other by the hinges 30 so as to be rotatable.

  In the present invention, the unwired core wire storage portion is provided on the outer surface of the core wire storage tray 25. In this embodiment, the side edge of the metal plate tray 27 opposite to the hinge 29 is bent upward to form the wall 27a, so that the side of the wall 27a and the core wire storage tray 25 can be formed. An unwired core wire accommodating groove (unwired core wire housing portion) 35 is formed between the two. In the illustrated example, the wall portion 27a of the tray base 27 for forming the unwired core wire accommodation groove 35 is a continuous wall portion, but it may be a wall portion that is partially cut away.

  The details of the core wire storage tray 25 will be described mainly with reference to FIG. 4. The core wire storage tray 25 is an elongated oval shape as viewed from above, and has a side wall 36 on the periphery, and a core wire inlet / outlet on both sides. 37 a, 37 b, 37 c, 37 d, provided with a tongue-shaped core wire presser 38 extending inward at a plurality of locations on the inner surface side of the side wall 36, and a fusion splicing region 39 on both sides of the extra length storage space at the center It has. As shown in FIG. 4, the fusion splicing region 39 includes a plurality of fusion sleeve holders 40 that fit and hold the fusion splicing portion 7 (fusion reinforcing sleeve) of the optical fiber core wire.

The embodiment of cable introduction in the above-mentioned branch connection box 11 will be described. FIGS. 8 and 9 show the case of the post-branch connection method performed without cutting the slot rod, and the main cable 1 which is a trunk cable is outside the fixed length portion. The cover is peeled off, and the slot rod 1d is exposed and passes through the branch connection box 11. The main cable 1 passes through the end face plate 20 and is gripped by the cable gripping fitting 13 at both side portions of the connecting rod 12. The main cable 1 (and the branch cable 3) is pressed and held from both the left and right sides in the horizontal direction by unillustrated demon bolts screwed to the cable holding brackets 13 on the left and right sides of the cable.
The figure shows a state in which the branch cable 3 is introduced from one side (left side) of the branch connection box 11 and the drop cable 2 is introduced from the other side (right side). The branch cable 3 penetrates the end face plate 20 and is gripped by the cable gripping bracket 13, and the tension member 3 e exposed from the slot rod is gripped by the tension member gripping bracket 14 (FIG. 9 illustrates the branch cable). Omitted). The drop cable 2 penetrates the end face plate 20 and is held by the drop cable holding fitting 15.

10 to 12 schematically show the manner of connecting the core wires in the core wire storage tray 25. FIG.
FIG. 10 shows a case where only the drop cable 2 is pulled down from the main cable 1 and a straight connection. The optical fiber core wire 1 a drawn from the main cable 1 and the optical fiber core wire 2 a of the drop cable 2 are fusion-connected, and a fusion-bonding portion (fusion-bonding sleeve) 7 is disposed in the fusion-sleeve holder 40. . In this case, the optical fiber cores 1a and 2a are introduced from the core wire inlets and outlets 37a and 37b, and the core wire surplus portions are stored in the center surplus length storage portion 44a and the surplus length storage portions 44b on both sides ( In FIG. 10, the central extra length storage portion 44a).
Then, an unused optical fiber core wire (unwired core wire) 1b drawn from the main cable 1 for use in drawing into a future subscriber is accommodated in a tube 42 such as nylon, and the core wire storage tray. 25 is housed in the unwired core wire housing groove 35 provided on the side portion of 25. The material of the tube 42 is not limited to nylon, and various materials such as Teflon can be used, but those having a smooth surface are suitable.

In the branch connection box in which the branch drop cable has been pulled out as described above, when it becomes necessary to later drop the unwired core wire as the operation line, the unwired core wire 1b is connected to the unwired core wire outside the core wire storage tray 25. What is necessary is just to take out the whole tube 42 from the accommodation groove | channel 35. FIG. Therefore, unlike the prior art, in order to take out the unwired core wire from the core wire storage tray, there is no need to touch the operation line in which the extra length portion is stored in the core wire storage tray. Therefore, it is possible to prevent communication failure by touching the operation line.
In the embodiment, since the unwired core wire receiving groove 35 is provided on the side surface opposite to the hinge 29 of the core wire storage tray 25, the unwired core wire receiving groove 35 is placed in front of the core wire storage tray 25 during the operation. This is preferable in terms of workability.

FIG. 11 shows the case where only the drop cable 2 is pulled down from the main cable 1, but shows a so-called pine needle connection. The optical fiber core wire 1a of the main cable 1 and the optical fiber core wire 2a of the drop cable 2 are connected in the same manner as described above, but the optical fiber core wire 1a of the main cable 1 to be connected and the optical fiber core wire of the drop cable 2 are connected. This is the case when 2a is on the same side.
The unused optical fiber core wire (unwired core wire) 1b drawn from the main cable 1 is housed in the tube 42 and in the unwired core wire housing groove 35 in the same manner as described above.

FIG. 12 shows a case where the branch cable 3 is branched from the main cable 1. The optical fiber core wire 1a drawn from the main cable 1 and the optical fiber core wire 3a of the branch cable 3 are connected in the same manner as described above.
Further, the unused optical fiber core wire (unwired core wire) 1b drawn from the main cable 1 is accommodated in the tube 42 in the same manner as described above, and is accommodated in the unlined core wire accommodation groove 35. Although the branch cable 3 is located on the main cable 1, it is shown as being shifted laterally so that it can be easily distinguished.

10 to 12, the case where the drop cable 2 is pulled down from the main cable 1 and the case where the branch cable 3 is branched from the main cable 1 are individually described. However, the drop cable from the main cable 1 is described. Of course, there are cases where both the withdrawal of 2 and the branch of the branch cable 3 are performed.
Moreover, although the above-mentioned embodiment is the case of the branch connection method after the slot rod is not cut, the present invention can naturally be applied to the method of the branch connection method by cutting the slot rod.

FIG. 13 shows another embodiment of the present invention. As shown in the figure, the unwired core wire receiving groove 35 ′ can be formed integrally with the plastic core wire storage tray 25 ′.

In the above embodiment, since the unwired core wire receiving groove 35 is provided on the side surface opposite to the hinge 29 of the core wire storage tray 25, it is preferable in terms of workability, but it is provided on the same side as the hinge 29, or The provision on the lower surface side of the core wire storage tray 25 is not necessarily excluded.
Moreover, although the groove | channel (unwired core wire accommodation groove | channel 35) was provided as an unwired core wire accommodating part in the Example, shapes other than a groove | channel may be sufficient.
Moreover, although the above-mentioned branch connection box for optical cables has been described as an optical closure that can drop a drop cable of a subscriber network, it can be applied to other optical closures. In short, it can be applied as a branch connection box for optical cables for various applications in which the fusion spliced portion and the extra lengths of the core wires before and after the fusion spliced portion are accommodated and the unwired core wires need to be provided in reserve.

It is a front view which shows the internal structure of the branch connection box for optical cables of one Example of this invention. It is a top view of the branch connection box for optical cables of FIG. It is an expansion left view of the principal part of FIG. It is a principal part enlarged view of the core wire storage tray part in FIG. FIG. 5 is a left side view of FIG. 4 (however, shown with a tray table fixing pin pulled); FIG. 6 is a view showing a state where the core wire storage tray of FIG. 5 is raised by turning around a hinge axis. It is the left view of FIG. 4 shown in the state which put the tube in the groove | channel for tube arrangement | positioning. It is a figure explaining the aspect of optical cable introduction to said branch connection box for optical cables, and is the figure which added and showed the optical cable to FIG. It is a figure explaining the aspect of optical cable introduction to said branch connection box for optical cables, and is the figure which added and showed the optical cable in FIG. It is a schematic diagram explaining an example of the core wire connection form in said branch connection box for optical cables. It is a schematic diagram explaining the other example of the core wire connection form in said branch connection box for optical cables. It is a schematic diagram explaining the further another example of the core wire connection form in said branch connection box for optical cables. It is typical sectional drawing of the core wire storage tray in the branch connection box for optical cables of the other Example of this invention. It is a schematic diagram explaining the conventional branch connection box for optical cables.

Explanation of symbols

1 Main cable 1a, 2a, 3a Optical fiber core wire 1b Optical fiber core wire (unwired core wire)
1d Slot rod 2 Drop cable 3 Branch cable 3e Tension member 7 Fusion splicer (fusion reinforcement sleeve)
11 Branch connection box for optical cable 12 Connecting rod 13 Cable gripping bracket 14 Tension member gripping bracket 15 Drop cable gripping bracket 16 Suspension bracket 17 Arm 18 Messenger wire (support wire)
19 Closure sleeve 20 End face plate 21 Arm insertion hole 22 Main cable insertion hole 23 Branch cable insertion hole 24 Drop cable insertion hole 25, 25 'Core wire storage tray 27 Tray base 27a Wall 28 Screw 29 Hinge 31 Tray base fixing pin 35 35 'unwired core wire groove (unwired wire housing part)
36 Side wall 37a, 37b, 37c, 37d Core entry / exit port 38 Core wire retainer 39 Fusion splicing region 40 Fusing sleeve holder 42 Tubes 44a, 44b Extra length storage

Claims (4)

An optical cable branch connection box having an optical connection portion between an optical fiber core wire drawn from a main cable and an optical fiber core wire of a drop cable and / or a branch cable and a core wire storage tray for storing an extra length of the core wire. ,
The unwired core wire drawn from the main cable for future operation is accommodated in a tube made of flexible resin, and the unwired core wire accommodating portion for accommodating the unwired core wire together with the tube is accommodated in the core wire. A branch connection box for optical cables, which is provided on an outer surface of a tray.   2. The branch connection box for optical cables according to claim 1, wherein the unwired core wire accommodating portion is a groove provided along a side surface in the width direction of the core wire storage tray.   The groove is formed by a wall portion on the side surface in the width direction of the core wire storage tray and a wall portion obtained by bending the edge portion in the width direction of the tray base made of a metal plate upward. Branch connection box for optical cables as described.   3. The branch connection box for optical cables according to claim 2, wherein the groove is formed by integral molding with a plastic core wire storage tray.

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