JP2004354895A - Branching tool, optical fiber branching method and optical fiber branching device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent occurrence of dispersion in the quality of a branching section when a multi-core optical fiber is branched into single core optical fibers. <P>SOLUTION: A branching tool 6 is provided with a flat section 9a on one side and branching line guiding grooves 10 on the other side. In the example of the tool 6 shown in the figure, tip parts of tubes 4 are respectively stored in four branching line guiding grooves 10 and fixed by adhesive. Then, UV element wires (single core optical fibers ) 3 that are exposed from an optical fiber tape cord 2 are inserted into the tubes 4 which are stored and fixed to the branching line guiding grooves 10. Then, the portions which are branched in a radial manner of the exposed UV element wires 3 are fixed to the flat section 9a by adhesive 17 and the branching tool 6 is stored in a protective case 7. Since the branched UV element wires 3 are inserted into the tubes 4 which are orderly fixed on the tool 6, the branching is properly conducted and occurrence of the problem of dispersion in quality of the branching section caused by the skill of an operator is prevented. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a branching tool for branching a multi-core optical fiber into a single-core optical fiber, an optical fiber branching method using the branching tool, and an optical fiber branching device.
[0002]
[Prior art]
When a multi-core optical fiber cord is branched into a single-core optical fiber, for example, a UV strand, a UV tube exposed from the multi-core optical fiber cord is loosely covered with a tube for protection. In such a case, conventionally, a branch portion is formed by bonding and fixing the tubes in a bale stack shape as they are. In some cases, the branch portion may be housed in the protective case to reinforce it, but even in such a case, the adhesive is applied in a state where the tubes are housed in the protective case in a bale-stacked state or simply arranged side by side. Filled and fixed.
[0003]
[Problems to be solved by the invention]
As in the conventional case described above, in the case where a tube covered on a single-core optical fiber is simply stacked in a bale shape and bonded and fixed to form a branch portion, stress is generated in the optical fiber after completion of the branch portion due to the skill of an operator or the like. However, there is a problem that the quality of the branch portion varies. Even if the branch portion is housed in the protective case and fixed by bonding, the same problem may occur.
SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional drawbacks, and when branching from a multi-core optical fiber to a single-core optical fiber, a branching tool capable of preventing a variation in the quality of a branch portion, and An object of the present invention is to provide an optical fiber branching method using a branching tool and an optical fiber branching device.
[0004]
[Means for Solving the Problems]
The invention according to claim 1 for solving the above problems is a branching tool for branching a multi-core optical fiber into a single-core optical fiber,
One side portion in the longitudinal direction of the substrate is a flat portion on which the substantially radially branched portion of each single-core optical fiber exposed from the multi-core optical fiber is placed, and the other side portion in the longitudinal direction is spaced apart in the branching tool width direction by a plurality of portions. A wall is provided, and a plurality of branch line guide grooves for accommodating and fixing a covering portion covering each single-core optical fiber are formed.
[0005]
According to a second aspect, of the plurality of branch line guide grooves in the branching tool of the first aspect, the side surface of the flat portion side portion of the branch line guide groove that is outside from the center in the width direction of the branching tool is branched from the upper surface. It is characterized by being curved from the outside in the tool width direction to the center.
According to a third aspect of the present invention, in the branching tool of the first aspect, a surface of the substrate in the vicinity of the front end of the flat portion is inclined upwardly toward the front end.
[0006]
The invention of claim 4 is an optical fiber branching method for branching a multi-core optical fiber into a single-core optical fiber using the optical fiber branching tool of claim 1, 2, or 3.
A substantially radial branch portion of each single-core optical fiber exposed from the multi-core optical fiber is fixed to a flat portion of a substrate of the branching tool with an adhesive, and a tube covered on each single-core optical fiber is connected to the branching tool. It is housed in the branch line guide groove and fixed with an adhesive.
[0007]
The invention of claim 5 is an optical fiber branching method for branching a multi-core optical fiber into a single-core optical fiber using the optical fiber branching tool of claim 1, 2, or 3.
After receiving the vicinity of the end of the tube in each branch line guide groove of the branching tool in advance and fixing with an adhesive, each of the single-core optical fibers exposed from the multi-core optical fiber is inserted into the corresponding tube. In addition, a substantially radially branched portion of each exposed single-core optical fiber is fixed to a flat portion of the substrate of the branching tool with an adhesive.
[0008]
The invention according to claim 6 is an optical fiber branching device for branching a multi-core optical fiber into a single-core optical fiber,
The branching tool according to claim 1, 2 or 3 is housed in a cylindrical protective case.
[0009]
According to a seventh aspect of the present invention, in the optical fiber branching device of the sixth aspect, a mounting portion having a through hole is integrally formed on an outer surface of the protective case.
[0010]
According to an eighth aspect of the present invention, in the optical fiber branching device according to the sixth aspect, a flange is formed at a branch outgoing end of the branching tool, and a step portion for locking the flange of the branching tool is formed at an opening of the protective case. It is characterized by the following.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 1 shows one embodiment of the present invention, and is a horizontal sectional view near a branching portion from a multi-core optical fiber to a single-core optical fiber. In this embodiment, a four-core optical fiber tape cord (multi-core optical fiber) 2 is branched into four single-core optical fibers 3 using an optical fiber branching device 1 as shown in the figure. The single-core optical fiber 3 according to the embodiment is a 250-μm-diameter UV strand obtained by coating a bare fiber with a UV resin coating. The tube (coating portion) 4 that covers (loosely) the protection loose on the UV element wire 3 is a 0.9 mm diameter tube made of a resin such as nylon or Hytrel (trademark of DuPont). However, the diameter, material, and structure of the tube 4 are not limited to the above, and are arbitrary.
[0012]
The optical fiber branching device 1 includes a branching tool 6 and a protective case 7 for housing the branching tool.
As shown in detail in FIGS. 2 and 3, the branching tool 6 is formed by connecting one side in the longitudinal direction of the elongated rectangular substrate 8 (the left half in FIGS. 3A and 3B) to an optical fiber tape cord. A flat portion 9 on which a substantially radially branched portion of each of the UV strands (single-core optical fibers) 3 exposed from 2 is placed, and a flat portion 9 on the other side in the longitudinal direction (the right half in FIGS. 3A and 3B). Four branch line guide grooves 10 corresponding to the core are provided. The branch line guide groove 10 is provided with three partition walls 11 on the other side in the longitudinal direction of the substrate 8 at intervals in the branching tool width direction (vertical direction in FIG. It is formed by providing a comb-shaped cross section. The partition wall 11 is formed with a notch 11b at an intermediate position so that the partition wall 11 has flexibility so that it can be held flexibly when the tube 4 is accommodated in the branch line guide groove 10, and is separated into two. I have.
Of the four branch line guide grooves 10, two branch line guide grooves 10 at the center portion are entirely linear when viewed from above, but the two outside branch line guide grooves 10 are As shown in FIG. 3 (a), the groove side surfaces 11a and 12a of the flat portion side portion (central portion in the longitudinal direction of the branching tool) are curved so as to face from the outside in the width direction of the branching tool toward the center when viewed from above. I have. This curved radius is set to an appropriate radius such that each UV element wire 3 is smoothly guided to the branch line guide groove 10.
The surface near the tip of the flat portion 9 of the substrate 8 (near the left end in FIGS. 3A and 3B) is inclined upward toward the tip. The ascending slope is indicated by 9a. The inclined surface 9a is also set to an appropriate inclination such that the difference in height corresponding to the thickness of the tube 4 is absorbed and the UV wires 3 are guided into the tube 4 without bending.
Further, a flange 13 is formed at the branching-out end of the branching tool 6 (the right end in FIGS. 3A and 3B).
[0013]
As shown in FIGS. 4 and 5, the protective case 7 has a generally elongated cylindrical shape, and has a mounting portion 15 integrally formed on a side surface thereof, for example, having a through hole through which a mounting screw passes. . The outer shape of the cylindrical protective case 7 is rectangular, but the interior is composed of a rectangular hollow portion 16a into which the branching tool 6 is inserted, and a slightly narrow oval hollow portion 16b through which the optical fiber tape cord 2 is passed. I have. Further, a step portion 14 for locking the flange 13 of the branching tool 6 is formed in the opening of the protective case 7. As a result, when the branching tool 6 is accommodated in the protective case 7, the branching tool 6 is automatically and correctly positioned just by pushing the branching tool 6 until it stops.
[0014]
The procedure for branching from the optical fiber tape cord 2 to the single-core optical fiber core 4 using the above-described optical fiber branching device 1 will be described. The vicinity of the end is housed and fixed with an adhesive. Next, the UV wire 3 exposed from the optical fiber tape cord 2 is inserted into the tube 4 housed and fixed in the branch line guide groove 10. Then, a portion of the exposed UV strand 3 radially branched is fixed to the flat portion 9a with an adhesive 17. The type of the adhesive is not particularly limited, and is arbitrary.
This means that the branch portion has been processed. In order to reinforce this branch portion, the branched optical fiber tape cord 2 is inserted into the protective case 7 from the right side in FIG. Is inserted and pushed until the flange 13 of the branching tool 6 hits the step portion 14 of the opening of the protective case 7 to complete the reinforcement of the branch portion.
[0015]
In the above, since each UV strand 3 of the optical fiber tape cord 2 is inserted into the tube 4 aligned and fixed on the branching tool 6, it is branched in an orderly manner, and the quality of the branch part is improved by the skill of the operator. The problem that variations occur can be prevented. In particular, the vicinity of the flat portion side of the outer branch line guide groove 10 is curved with a moderate radius from the outside in the branching tool width direction toward the center, and smoothly leads to radial branching of the UV element wire 3. Each UV strand 3 is smoothly guided into the tube 4 in the branch line guide groove 10. Also in this regard, the UV wires 3 can be guided to the tube 4 so as not to cause excessive stress, and the quality of the branch portion can be improved.
[0016]
The present invention is applicable to various branches of multi-core optical fibers. The multi-core optical fiber to which the present invention can be applied is not limited to the tape-like multi-core optical fiber as in the embodiment, nor is it limited to the presence or absence of a tensile material such as Kevlar, We do not stick to the names of cables and cables.
In addition, the single-core optical fiber branched from the multi-core optical fiber is the UV element wire 3 in the embodiment, but is not limited thereto, and the names of the core wire, the cord, the cable, and the like are not limited. In the case where the branched single-core optical fiber is a single-core optical fiber cord, the single-core optical fiber already has a covering portion, and thus can be housed and fixed in the branch line guide groove 10 without covering the tube.
[0017]
【The invention's effect】
According to the branching tool of the present invention, since the flat part is provided on one side and the branch line guide groove is provided on the other side, the single-core optical fiber exposed from the multi-core optical fiber can be aligned and branched. The problem of variation in the quality of the branch part due to the skill of the present invention can be prevented.
[0018]
As described in claim 2, of the plurality of branch line guide grooves, the side surface of the flat part side portion of the branch line guide groove located outside from the center in the branch tool width direction is outside in the branch tool width direction when viewed from above. When curved with an appropriate radius that is directed toward from the center, the single-core optical fiber is smoothly guided to the branch line guide groove side, and it is possible to prevent the occurrence of excessive stress on the optical fiber and improve the quality of the branch portion. be able to.
Further, when the surface near the front end of the flat portion of the substrate is inclined upwardly toward the front end, the single-core optical fiber can be prevented from being bent by the thickness of the covering portion (tube). Unreasonable stress can be prevented from being generated in the optical fiber.
[0019]
The present invention is suitable for a case in which a tube is covered as a coating part on a branched single-core optical fiber as in claim 4, and it is possible to prevent a variation in the quality of the branch part due to the skill of an operator, which easily occurs in that case. .
In particular, according to the method for inserting the single-core optical fiber into the tube after the tube to be placed on the branched single-core optical fiber is housed and fixed in the branch line guide groove of the branching tool as described in claim 5, It is even more effective in preventing variations in the quality of the branch due to skills.
[0020]
By housing the branching tool in the protective case, the branching portion can be sufficiently reinforced.
Further, when the flange is formed on the branching tool side and the stepped portion for locking the flange is formed on the protective case side, the branching tool can be easily and correctly positioned and accommodated in the protective case.
[Brief description of the drawings]
FIG. 1 shows one embodiment of the present invention, and is a horizontal sectional view of a branch portion from a multi-core optical fiber to a single-core optical fiber.
FIG. 2 is a perspective view of the branching tool in FIG.
3 shows the branching tool of FIG. 2, wherein (a) is a plan view, (b) is a front view, and (c) is a right side view.
FIG. 4 is a perspective view of the protection case of FIG. 1;
FIG. 5 is a horizontal sectional view of the protection case of FIG.
[Explanation of symbols]
1 optical fiber branching device 2 optical fiber tape cord (multi-core optical fiber)
3 UV strand (single core optical fiber)
Reference Signs List 4 Tube 6 Branching tool 7 Protective case 8 Board 9 Flat part 10 Branch line guide groove 11 Partition wall (wall)
11a, 12a (curved) groove side surface 12 outer side wall (wall)
13 Tsuba 14 Step

Claims (8)

A branching tool for branching a multi-core optical fiber into a single-core optical fiber,
One side portion in the longitudinal direction of the substrate is a flat portion on which the substantially radially branched portion of each single-core optical fiber exposed from the multi-core optical fiber is placed, and the other side portion in the longitudinal direction is spaced apart in the branching tool width direction by a plurality of portions. A branching tool comprising a wall and a plurality of branch line guide grooves formed therein for accommodating and fixing a covering portion covering each single-core optical fiber. Among the plurality of branch line guide grooves, the groove side surface of the flat portion side portion of the branch line guide groove located outside from the center of the branch tool width direction, as viewed from the upper surface, faces from the outside in the branch tool width direction to the center. The branching tool according to claim 1, wherein the branching tool is curved. The branching tool according to claim 1, wherein a surface of the substrate near a flat portion front end is inclined upward toward the front end. An optical fiber branching method for branching a multi-core optical fiber into a single-core optical fiber using the optical fiber branching tool according to claim 1, 2, or 3.
A substantially radial branch portion of each single-core optical fiber exposed from the multi-core optical fiber is fixed to a flat portion of a substrate of the branching tool with an adhesive, and a tube covered on each single-core optical fiber is connected to the branching tool. An optical fiber branching method characterized by being housed in a branch line guide groove and fixed with an adhesive. An optical fiber branching method for branching a multi-core optical fiber into a single-core optical fiber using the optical fiber branching tool according to claim 1, 2, or 3.
After receiving the vicinity of the end of the tube in each branch line guide groove of the branching tool in advance and fixing with an adhesive, each of the single-core optical fibers exposed from the multi-core optical fiber is inserted into the corresponding tube. An optical fiber branching method comprising: fixing a substantially radially branched portion of each exposed single-core optical fiber to a flat portion of a substrate of a branching tool with an adhesive. An optical fiber branching device for branching a multi-core optical fiber into a single-core optical fiber,
An optical fiber branching device, wherein the branching tool according to claim 1, 2 or 3 is housed in a cylindrical protective case. The optical fiber branching device according to claim 6, wherein a mounting portion having a through hole is integrally formed on an outer surface of the protective case. 7. The optical fiber branch according to claim 6, wherein a flange is formed at an end of the branching tool on the branch exit side, and a step portion for locking the flange of the branching tool is formed at an opening of the protective case. apparatus.

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