JP2011002699A - Method for reinforcing coated optical fiber and structure for reinforcing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for reinforcing coated optical fiber capable of forming a multi-core connection part by reinforcing coated optical fiber connection parts of a desired number conveniently and reliably in the lump.SOLUTION: The plurality of coated optical fiber connection parts 5 protected by protective tubes are arrayed on a pressure-sensitive adhesive sheet 12 of which one end is restrained by a core material 11, thereafter, the pressure-sensitive adhesive sheet 12 is wound while causing the core material 11 to serve as a shaft; thereby, the plurality of coated optical fiber connection parts 5 are arranged around the core material 11 and, further, the other end of the pressure-sensitive adhesive sheet 12 is adhered onto an outer circumferential surface of the pressure-sensitive adhesive sheet 12 to reinforce the plurality of coated optical fiber connection parts 5 in the lump.

Description

  The present invention relates to a technique for reinforcing a core connecting portion of an optical fiber core, and more particularly to a method for reinforcing an optical fiber core for collectively reinforcing a plurality of core connecting portions and a reinforcing structure using the method.

  Conventionally, optical fiber cores are connected by fusion-bonding by removing the fiber coating portion at the connection end and heating and melting the exposed butted end portion of the bare fiber portion of glass. Normally, the bare fiber part, which has been removed from the fiber coating and is fusion-spliced, has a low mechanical strength and is reinforced by a reinforcing member. As the reinforcing member, for example, a heat-shrinkable tube made of a heat-meltable resin is accommodated by attaching a reinforcing rod in a heat-shrinkable tube that shrinks in the radial direction when heated.

  Further, as shown in FIG. 5, a plurality of optical fiber cores 102 are arranged in a planar shape, and a common coating layer 103 is provided on these optical fibers to integrate them, or as shown in FIG. Such a multi-core optical fiber cable in which a plurality of optical fiber cores 102 are accommodated in a cable 104 is known. In the figure, reference numeral 101 denotes a bare glass fiber portion exposed by removing the fiber coating portion of the optical fiber core wire 102.

  FIG. 7 is a view for explaining a connection technique of optical fiber core wires in the multi-core optical fiber cable shown in FIG. FIG. 7A shows the connection state of the optical fiber core wires, and FIG. 7B shows the XX ′ cross section of the core wire connection portion. A multi-core optical fiber cable 104 containing a plurality of optical fiber cores 102 is divided into individual optical fiber cores 102 in the vicinity of the ends thereof, and the bare fiber portions 101 of the respective optical fiber cores 102 are fused. Connected. Each fusion splicing portion (hereinafter referred to as a core wire connecting portion) is formed by a reinforcing member such as a heat-shrinkable tube 105 that houses a reinforcing core 106 inside and has a hot-melt adhesive 107 on the inner surface. Reinforced.

  In the above, since the individual optical fiber cores are fused and connected one by one and the core connection parts are individually reinforced, each core connection part is in a disjoint state. However, if the core connection parts are separated, the optical fiber cores may be entangled with each other, and the core connection parts may be damaged. It is desirable to put them together in a junction box or the like.

  Conventionally, as a technique for collectively reinforcing a plurality of core wire connection portions, for example, in Patent Document 1, by arranging a plurality of independent optical fiber core wires in a planar shape and clamping them with a terminal fixing jig, A method is described in which a plurality of core wire connection portions are combined into a tape (ribbon) shape, and these are collectively reinforced with a hot melt adhesive and a heat shrinkable tube.

  Patent Document 2 describes a reinforcing member that accommodates a plurality of core wire connection portions without taking up a large accommodation space. The reinforcing member is composed of a heat-shrinkable tube, a tensile body, and a heat-meltable adhesive, and a core-wire guide part that guides the optical fiber core wire through the heat-shrinkable tube and penetrates the reinforcing member. Are provided.

JP-A-63-194208 JP 9-297243 A

  However, in the technique described in Patent Document 1, a terminal fixture for arranging and clamping a plurality of optical fiber cores in a planar shape and a terminal for connecting the terminals of the plurality of optical fiber cores together. A multi-core fusion machine is required. A method of bundling a plurality of optical fiber core wires into a tape and connecting and reinforcing them at once using a multi-fiber fusion machine is useful, but there are actually many contractors who have only a single-core fusion machine. . This single-core fusion machine is highly reliable because it can align the cores of optical fiber core wires, and is widely used. In addition, since a multi-core fusion machine is expensive, a simple method that can reinforce a plurality of core wire connection portions without using a multi-core fusion machine is required.

  Moreover, in the technique described in Patent Document 2, it is possible to reduce the space for accommodating a plurality of core wire connection portions, but in order to collectively accommodate and reinforce a plurality of core wire connection portions in one reinforcing member, Temporarily placed on the reinforcing device in order from the fusion-bonded optical fibers. The temporarily placed optical fiber core wire is held until the fusion splicing of all the optical fiber core wires to be accommodated is completed with the fused portion exposed. It is not preferable to expose the fused part naked in this way, because the fused part may be accidentally damaged.

  The present invention has been made in view of the above circumstances, and a method for reinforcing an optical fiber core wire capable of forming a multi-core connection portion by simply and reliably reinforcing a desired number of core connection portions together. And it aims at providing the reinforcement structure by this method.

  An optical fiber core reinforcing method according to the present invention is an optical fiber core reinforcing method for collectively reinforcing core connecting portions of a plurality of optical fiber cores, one end of which is locked to a core material. After arranging a plurality of core wire connection portions protected by the protective tube on the adhesive sheet, by winding the adhesive sheet around the core material, a plurality of core wire connection portions are arranged around the core material, The other end of the pressure-sensitive adhesive sheet is fixed on the outer peripheral surface of the pressure-sensitive adhesive sheet to reinforce a plurality of core wire connecting portions.

  The optical fiber core reinforcing structure according to the present invention includes a collective reinforcing portion in which a plurality of core connecting portions are collectively strengthened by the above-described optical fiber core reinforcing method.

  According to the present invention, the core wire connecting portions protected by the protective tube are arranged on the adhesive sheet, and the adhesive sheet is wound around the core material, whereby the core wire connecting portions of the desired number of optical fiber core wires are wound. Can be reinforced in a simple and reliable manner to form a multi-core connecting portion.

It is a figure which shows an example of the core wire connection part of the optical fiber core wire by this invention. It is a figure which shows an example of the package reinforcement member by this invention. It is a figure for demonstrating an example of the reinforcement method of the optical fiber core wire which concerns on the 1st Embodiment of this invention. It is a figure for demonstrating an example of the reinforcement method of the optical fiber core wire which concerns on the 2nd Embodiment of this invention. It is a figure explaining the prior art. It is a figure explaining the prior art. It is a figure for demonstrating the connection technique of the conventional optical fiber core wire.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of a method for reinforcing an optical fiber core wire according to the present invention and a reinforcing structure using the method will be described with reference to the accompanying drawings. In the drawings, the same components are denoted by the same reference numerals, and repeated description is omitted.

  FIG. 1 is a diagram showing an example of a core connecting portion of an optical fiber core according to the present invention. 1A is a cross-sectional view of the core wire connection portion before the heat treatment as seen from the side surface, FIG. 1B is a cross-sectional view of the core wire connection portion after the heat treatment as seen from the side surface, and FIG. It is sectional drawing (YY 'cross section) which looked at the core wire connection part of FIG. 1 (A) from the axial direction. In the figure, 1 is an optical fiber core, 2 is a bare fiber part, 3 is a fiber coating part, 4 is a fusion part, 5 is a core wire connection part, 6 is a heat-shrinkable tube, and 7 is a heat-meltable tube. .

  The optical fiber core wire 1 is fusion spliced by arc discharge or the like with the end of the bare fiber portion 2 exposed by removing the fiber covering portion 3 at the connection end. The core wire connecting portion 5 has a length that covers a predetermined range of the fiber covering portions 3 on both sides of the bare fiber portion 2 and is made of ethylene vinyl acetate (abbreviation: EVA) or the like in a heat-shrinkable tube 6 such as polyethylene resin. A hot-melt tube 7 made of hot-melt adhesive resin is housed and configured. In addition, a reinforcing rod such as stainless steel or glass may be housed in the core wire connecting portion 5 and configured.

  The spliced optical fiber core wire 1 is inserted into the heat-meltable tube 7 so that the fusion part 4 is positioned at the approximate center, and is heated by a suitable heating means (not shown). By this heating, the heat-meltable tube 7 is softened and melted, and the heat-shrinkable tube 6 is contracted in the inner diameter direction.

  Due to the shrinkage of the heat-shrinkable tube 6, the heat-meltable tube 7 heated and melted covers the bare fiber portion 2 so as to fill a space in the heat-shrinkable tube 6. When the heat-shrinkable tube 6 and the melted heat-meltable tube 7 are cured, the fused portion 4 including the part of the fiber coating portion on both sides of the bare fiber portion 2 is formed as shown in FIG. Protect and reinforce over a specified range.

  FIG. 2 is a view showing an example of a collective reinforcing member according to the present invention. In the figure, 10 is a collective reinforcing member, 11 is a core material, 12 is an adhesive sheet, and 12a is an adhesive surface. The collective reinforcement member 10 includes a core material 11 and an adhesive sheet 12 having one end locked to the core material 11. That is, the core material 11 is fixed to the end of the pressure-sensitive adhesive surface 12a of the pressure-sensitive adhesive sheet 12, and the pressure-sensitive adhesive sheet 12 is longer than the length in which a desired number (for example, twelve) of core wire connection portions 5 can be arranged. Has been cut. Moreover, the width | variety of the adhesive sheet 12 shall be cut about the length of the core wire connection part 5 to arrange. Further, as the core material 11, for example, a material formed of a material such as stainless steel or glass and having a circular cross section is used.

(First embodiment)
FIG. 3 is a diagram for explaining an example of a method for reinforcing an optical fiber core wire according to the first embodiment of the present invention. Assume that the collective reinforcing member 10 shown in FIG. 2 is placed on a tray (not shown). First, as shown in FIG. 3 (A), a plurality of core wire connecting portions 5 in which the ends of the optical fiber core wires 1 are fusion-connected are arranged on the adhesive sheet 12. The core wire connecting portion 5 of the present embodiment is covered with a protective tube, and the protective tube is composed of a heat-shrinkable tube containing a heat-meltable resin as shown in FIG. The core wire connecting portion 5 protected by the heat-shrinkable tube is preliminarily heat-treated, and the heat-shrinkable tube is filled with a heat-meltable resin.

  Then, as shown in FIG. 3B, after arranging a desired number (for example, twelve) of the core wire connecting portions 5, the adhesive sheet 12 is wound around the core material 11 in the direction of the arrow. A plurality of core wire connecting portions 5 are arranged around the material 11.

  And as shown in FIG.3 (C), the other end (margin) of the adhesive sheet 12 adheres on the outer peripheral surface of the adhesive sheet 12, and the several core wire connection part 5 is reinforced collectively. At this time, the outer peripheral surface of the pressure-sensitive adhesive sheet 12 may be reinforced with tape as necessary. In FIG. 3C, reference numeral 13 denotes a collective reinforcing portion obtained by reinforcing a plurality of core wire connecting portions 5 collectively. The present invention may be configured as a reinforcing structure of an optical fiber core wire having the collective reinforcing portion 13. In addition, you may store this collective reinforcement part 13 in a predetermined | prescribed storage case as needed.

  Thus, since the core material is arranged at one end of the pressure-sensitive adhesive sheet, a plurality of core wire connection portions can be easily arranged in accordance with the core material, and the plurality of arranged core wire connection portions are further arranged. Since the core material is used as a starting point, it can be wound in a laver shape, so that a plurality of core wire connecting portions can be easily combined.

Moreover, by arranging a plurality of core wire connection portions on the adhesive sheet, each core wire connection portion can be temporarily fixed so as not to move.
Moreover, since each core wire connection part is collectively reinforced in the state protected by the protection tube, a multi-core connection part can be formed reliably, without damaging a core wire connection part.
Moreover, since the length of an adhesive sheet can be adjusted freely, it can respond | correspond flexibly regardless of the accommodation number of the core wire connection parts.

(Second Embodiment)
FIG. 4 is a diagram for explaining an example of a method for reinforcing an optical fiber core according to the second embodiment of the present invention. The method according to the present embodiment will be described with reference to FIGS. 3A to 3C and FIGS. 4A and 4B.

  In this embodiment, the protective tube which protects the core wire connection part 5 is comprised with a heat melting tube. For example, this heat-meltable tube is passed through each optical fiber core wire 1 in advance. Then, after the end of the optical fiber core wire 1 is fused and connected, the heat-meltable tube is moved to the fusion part, and this fusion part is temporarily accommodated in the heat-melting tube. At this time, the heat-meltable tube may be properly heated and stopped so that it does not deviate from the fused portion. And the core wire connection part 5 protected by the heat-meltable tube is arranged on the adhesive sheet 12 as shown in FIG. 3A, as in the first embodiment.

  Then, as shown in FIG. 3B, after arranging a desired number (for example, twelve) of the core wire connecting portions 5, the adhesive sheet 12 is wound around the core material 11 in the direction of the arrow. A plurality of core wire connecting portions 5 are arranged around the material 11. And as shown in FIG.3 (C), the other end (margin) of the adhesive sheet 12 adheres on the outer peripheral surface of the adhesive sheet 12, and the several core wire connection part 5 is strengthened collectively, and the collective reinforcement part 13 is made. Form.

  Further, as shown in FIG. 4 (A), the heat-shrinkable tube 15 previously passed through the twelve optical fiber cores 1 is moved to the collective reinforcing portion 13 and shown in FIG. 4 (B). Thus, this collective reinforcement part 13 is accommodated in the heat-shrinkable tube 15. In addition, the cross-sectional radius of the collective reinforcing part 13 is formed to be slightly smaller than the cross-sectional radius of the heat-shrinkable tube 15, and the heat-shrinkable tube 15 can accommodate the collective reinforcing part 13. .

  Then, after the collective reinforcement portion 13 in which the plurality of core wire connection portions 5 are collectively reinforced is accommodated in the heat-shrinkable tube 15, as shown in FIG. 4C, the collective reinforcement portion 13 and the heat-shrinkable tube 15 are included. Are heated together to soften and melt each heat-meltable tube protecting each core wire connecting portion 5 and shrink the heat-shrinkable tube 15 in the inner diameter direction to complete the reinforcement. In addition, as a heating method, it is desirable to heat uniformly with the upper and lower divided heaters which carried out the semicircle, the hot air heater, etc. Moreover, in order to perform more effective reinforcement, it is desirable that the pressure-sensitive adhesive sheet 12 itself is formed of a hot-melt resin.

  In this embodiment, in addition to the effects of the first embodiment, each of the plurality of core wire connecting portions is temporarily protected by covering with a heat-meltable tube, and further, the plurality of core wire connecting portions together with the core material is an adhesive sheet. The heat-shrinkable tube is covered with a heat-shrinkable tube and heated, so that the heat-shrinkable tube can be filled with a heat-meltable resin and fixed together, improving reliability. be able to.

  As described above, according to the present invention, the core wire connection portions protected by the protective tube are arranged on the pressure-sensitive adhesive sheet, and this pressure-sensitive adhesive sheet is simply and reliably wound around the core material, A multi-core connection part (collective reinforcement part) can be formed by collectively reinforcing the core connection parts of a desired number of optical fiber cores.

DESCRIPTION OF SYMBOLS 1 ... Optical fiber core wire, 2 ... Bare fiber part, 3 ... Fiber coating | coated part, 4 ... Fusion part, 5 ... Core wire connection part, 6,15 ... Heat-shrinkable tube, 7 ... Heat-meltable tube, 10 ... Collective reinforcement member, 11 ... core material, 12 ... adhesive sheet, 12a ... adhesive surface, 13 ... collective reinforcement part.

Claims (5)

A method of reinforcing an optical fiber core for collectively reinforcing core connection portions of a plurality of optical fibers,
After arranging a plurality of core wire connecting portions protected by a protective tube on the adhesive sheet whose one end is locked to the core material, the adhesive sheet is wound around the core material around the core material. An optical fiber core in which the plurality of core wire connection portions are arranged, and the other end of the adhesive sheet is fixed on an outer peripheral surface of the adhesive sheet to collectively reinforce the plurality of core wire connection portions. Line reinforcement method.   The said protection tube is a heat-shrinkable tube which accommodated the heat-meltable resin, and the inside of this heat-shrinkable tube is filled with the said heat-meltable resin by heat processing. A method for reinforcing an optical fiber core.   The protective tube is a heat-meltable tube, and after the batch reinforcing portion obtained by batch reinforcing the plurality of core wire connecting portions is accommodated in the heat shrinkable tube, the batch reinforcing portion and the heat shrinkable tube are combined. 2. The method of reinforcing an optical fiber core according to claim 1, wherein the heat-meltable tube is softened and melted together and the heat-shrinkable tube is contracted in an inner diameter direction.   The method for reinforcing an optical fiber core wire according to claim 3, wherein the adhesive sheet is made of a heat-meltable resin.   An optical fiber core reinforcing structure having a collective reinforcing portion in which the plurality of core wire connecting portions are collectively reinforced by the optical fiber core reinforcing method according to claim 1.

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