JP4161821B2 - Fusion splicing reinforcement method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention is, after fusion splicing optical fiber ribbon multifiber relates fused connection reinforcement method for reinforcing the protective member to fusion splice.
[0002]
[Prior art]
Conventionally, fusion splicing of optical fibers is performed by removing the fiber coating portion at the connection end and fusing the fused end of the bare bare fiber portion by heating and fusing. The bare fiber portion, from which the fiber covering portion has been removed and fusion-spliced, has a low mechanical strength and is reinforced by a protective member. This protective member is usually configured by attaching a reinforcing rod to a heat-shrinkable tube that shrinks in the radial direction when heated and housing a heat-meltable tube made of a heat-meltable adhesive resin.
[0003]
FIG. 5 is a diagram showing a general method for reinforcing the fusion splicing portion, in which 1 is an optical fiber ribbon (tape core), 2 is a bare fiber portion, 3 is a fiber coating portion, and 4 is a fusion wire. Incoming connection part, 5 is a protective member, 6 is a heat shrinkable tube, 7 is a heat-meltable tube, 8 is a reinforcing rod, 9 is a heating table, 10 is a heater, and 11 is a heating mechanism.
[0004]
In FIG. 5, an optical fiber tape core wire 1 (hereinafter simply referred to as a tape core wire) in which a plurality of optical fibers are arranged in parallel and integrated with a common coating is removed by removing the fiber coating portion 3 at the connection end. The fiber part 2 is exposed, the ends are butted together, and fusion spliced by arc discharge or the like. The protective member 5 has a length that covers a predetermined range of the fiber coating portion 3 on both sides of the bare fiber portion 2, and a hot-melt adhesive resin-based heat-meltable tube 7 and stainless steel or glass, A reinforcing bar 8 made of ceramic or the like is accommodated.
[0005]
The heat-meltable tube 7 has, for example, an elliptical shape and a size such that a large number of optical fibers are accommodated in a line, and the reinforcing rod 8 is, for example, a semi-cylindrical one The thickness of the optical fiber is such that the optical fibers are arranged in a line on the flat surface. Then, the fusion-bonded tape core wire 1 is inserted into the heat-meltable tube 7 so that the fusion-bonding portion 4 is located in the center, and a heating mechanism 11 including a heating table 9 and a heater 10 is provided. Is heated by. By this heating, the heat-meltable tube 7 is softened and melted, and the heat-shrinkable tube 6 is contracted / reduced in the inner diameter direction.
[0006]
The heat-meltable tube 7 that has been heated and melted by shrinking / reducing the diameter of the heat-shrinkable tube 6 covers the periphery of the bare fiber portion 2 together with the reinforcing rod 8 so as to fill the space in the heat-shrinkable tube 6. When the heat-shrinkable tube 6 and the molten heat-meltable tube 7 are cured, the fusion splicing portion 4 is protected and reinforced over a predetermined range including a part of the fiber coating portions on both sides of the bare fiber portion 2.
[0007]
There is also known a method in which two fusion-bonded tape core wires are simultaneously reinforced with one protective member (see, for example, Patent Document 1). In the above-mentioned Patent Document 1, two 4-core tape core wires are inserted individually into a heat-meltable tube prepared for each tape core wire with a reinforcing bar having a rectangular or flat cross section interposed therebetween, and Similarly, the fusion splicing portion is protected and reinforced over a predetermined range. It is also disclosed that when the fusion spliced portion is protected by the protective member 5, heating is performed by applying a certain tension to the tape core wire 1.
[0008]
[Patent Document 1]
JP-A-9-297243
[Problems to be solved by the invention]
For example, when the number of the cores 1 to be spliced increases, for example, 24 cores, one of the cores to be spliced to each other is a 24-fiber optical fiber core and the other is a 12-core tape core Two may be used. In addition, two 12-core fiber cores may be arranged in parallel and fused together so that there are 24 cores on both sides that are fused together. In the multi-core batch fusion splicing, the lengths of all the optical fibers are aligned, and they are fused simultaneously using arc discharge or the like in a line. Thereafter, the fusion-spliced state is maintained, and the fusion-spliced portion is covered with the above-described tube-shaped protective member to perform protection and reinforcement.
[0010]
In this case, a large number of fusion-spliced optical fibers are arranged in a line, and it is easy to insert two tape core wires into the protective member with different directions by 180 ° as in Patent Document 1. However, when one side is formed by one tape core wire, it is substantially impossible. For this reason, the reinforcement after the plurality of tape core wires are arranged in parallel and fused together is inserted into the protective member and heat-treated with the optical fibers kept in a parallel row as described in FIG. .
[0011]
FIG. 6 is a diagram for explaining the problem in this case. In the figure, 1a to 1d denote tape core wires, 12a and 12b denote gripping mechanisms, and the other symbols are the same as those used in FIG. Therefore, the description is omitted. When a pair of tape cores 1a and 1b and a pair of 1c and 1d are arranged in parallel with each other and fusion-bonded and then the fusion-bonded portion is reinforced, two tape cores 1a and 1b, and 1c and In the case of 1d, it is assumed that many optical fibers are inserted into the protective member 5 so as to be arranged in a parallel line as in the case of fusion.
[0012]
The two tape cores 1a and 1b are held in parallel by the left gripping mechanism 12a in FIG. 6, and the counterpart tape cores 1c and 1d connected thereto are similarly parallel by the right gripping mechanism 12b. Are held side by side. The tape cores 1a, 1b and 1c, 1d arranged in parallel are inserted into the protective member 5 in a single row as shown in FIG.
[0013]
By the heating by the heating mechanism 11, the protective member 5 is contracted / reduced. Due to the reduced diameter of the protective member 5, as shown in FIG. 6 (C-B), the two tape cores 1a and 1b (1c and 1d are also in parallel) in the protective member 5 are mutually inside. Are separated into upper and lower parts and an overlapping portion Y is generated. Such overlap does not occur when the tape core is formed of one piece, but when the tape cores 1a and 1b are used side by side, the gripping force of the gripping mechanism is not sufficient and slipping is not possible. It is also caused by the tendency to occur. The overlapping portion Y generated in the protective member 5 may directly contact a bare fiber portion in the vicinity of the fusion splicing portion from which the fiber coating has been removed, thereby causing a fine flaw and disconnection.
[0014]
The present invention has been made in view of the above-described situation, and when reinforcing a fusion spliced portion that is a fusion spliced by arranging a plurality of optical fiber ribbons in parallel, the optical fibers overlap each other. providing a fused connection reinforcement method that does not cause an object.
[0016]
In the fusion splicing reinforcement method according to the present invention, after the optical fiber ribbon is fused and connected, the fusion splicing portion is inserted and covered in a single heat-meltable tube of the protective member, and then the splicing splicing portion. both sides were grasped by the gripping mechanism, Ru fusion splicing reinforcing method der heat treating the protective member that covers the fusion spliced portion by the heating mechanism. Then, a plurality of optical fiber ribbons of the, by gripping by the gripping mechanism having two or more gripping surfaces which are integrally formed with different angles, but which is adapted to heat treatment. In addition, the gripping surface of a different angle can be formed by two C-shaped surfaces.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
The outline of the embodiment of the present invention will be described with reference to FIGS. 1A is a plan view schematically showing a fusion splicing reinforcement device according to the present invention, FIG. 1B is a front view thereof, FIG. 1C is a side view thereof, and FIGS. These are figures explaining the operation of the present invention. In the figure, 1a to 1d are tape core wires, 2 is a bare fiber part, 3 is a fiber coating part, 4 is a fusion splicing part, 5 is a protective member, 6 is a heat shrinkable tube, 6 'is a reduced diameter tube, and 7 is Heat melting tube, 7 'is melt adhesive resin, 8 is a reinforcing rod, 9 is a heating base, 10 is a heater, 11 is a heating mechanism, 12a and 12b are gripping mechanisms, 13 is a heating mechanism fixing base, and 14 is a gripping mechanism fixing. A base 15 indicates an engaging pin.
[0018]
The fusion spliced optical fiber that is the subject of the present invention is one in which at least two optical fiber ribbons (hereinafter simply referred to as “tape ribbons”) are arranged in parallel and fused together. It should be noted that two or more tape cores may be used on one side connected to each other, and the other side may be one integrated tape core, or a single core It is also possible to simply arrange a plurality of.
[0019]
As shown in FIG. 1A, the fusion splicing is performed by removing the fiber coating portion 3 at the ends of the tape cores 1a to 1d to expose the bare fiber portion 2, and butting the connection ends. Thereafter, the connection ends are melted and fused together by arc discharge or the like. Since the fusion splicing portion 4 is mechanically weaker than other portions, reinforcement is performed. This reinforcement is performed by covering the bare fiber part 2 and part of the fiber coating part 3 in the vicinity of the fusion splicing part 4 with a sleeve-like protective member 5 and heating the protective member 5 with a heating mechanism 11 as in the conventional case. This is done by contracting. Then, the protective member 5 is inserted in advance on the tape core wire, is positioned so that the fusion splicing portion 4 is in the center after the fusion splicing, and is placed on the heating mechanism 11 of the reinforcing device. At this time, the optical fibers are held and fixed by the holding mechanisms 12a and 12b arranged on both sides so that the optical fiber does not move during heating or is not reinforced in a bent state.
[0020]
As shown in FIG. 1B, the gripping mechanisms 12 a and 12 b are installed on a gripping mechanism fixing base 14 provided on both sides of a heating mechanism fixing base 13 that supports the heating mechanism 11. In addition, it is possible to move in the axial direction of the optical fiber together with at least one of the gripping mechanisms 12a and 12b or the gripping mechanism fixing base 14 so that a predetermined tension is applied to the fusion splicing portion as in the prior art. It may be. Moreover, it is preferable that the gripping mechanisms 12a and 12b are detachably attached by the engagement pins 15 and screws or the like, and are configured to be exchangeable so as to be able to cope with a change in the type of the tape core wire, the number of wires used, and the like.
[0021]
In the present invention, as shown in FIG. 1C, when the tape cores 1a to 1d are gripped, the adjacent tape cores are gripped so as to be inclined in different directions. Although the specific gripping mechanism 12a12b will be described later, for example, the fusion-bonded tape cores 1a and 1b (and 1c and 1d) are tilted and fixed so as to form a letter C.
[0022]
FIG. 2 (A-I) shows a state in which the fusion-bonded tape cores 1a and 1b (and 1c and 1d) are inserted into the protective member 5 in a square shape and are heated and shrunk. The protective member 5 is configured by housing a single hot-melt adhesive resin-based heat-meltable tube 7 and a reinforcing rod 8 made of stainless steel, glass, ceramic or the like in a heat-shrinkable tube 6. The heat-meltable tube 7 is formed in a shape and size such that, for example, two tape cores 1a and 1b arranged in an elliptical shape and arranged in a C shape are inserted. A semi-cylindrical one is used. The fusion-bonded tape cores 1 a and 1 b (and 1 c and 1 d) are inserted into the heat-meltable tube 7 so that the fusion-bonding portion 4 is located at the center, and heated by the heating mechanism 11.
[0023]
As shown in FIG. 2 (A-B), the heat shrinkable tube 6 is contracted and contracted in the inner diameter direction by the heating mechanism 11 to become a contracted tube 6 ′, and the heat-meltable tube 7 is softened and melted. Thus, the molten adhesive resin 7 ′ fills the gap portion in the reduced diameter tube 6 ′. The tape cores 1a and 1b (or 1c and 1d) are bonded and integrated into the reduced-diameter tube 6 ′ by a molten adhesive resin 7 ′ in a state of maintaining a square shape together with the fusion spliced portion. That is, as described with reference to FIG. 6C, protection and reinforcement can be performed without causing overlap.
[0024]
FIG. 2B is a diagram illustrating another embodiment, and illustrates an example in which three tape cores are used. In this case, as in the example of FIG. 2A, the three tape core wires are gripped so that the angle of the gripping surface of the gripping mechanism is different (in this case, gripped in a trapezoidal shape), and FIG. As shown in (a), it is inserted into the protective member 5 in this gripping state. The protective member 5 is configured by housing a single hot-melt adhesive resin-based hot-melt tube 7 and a reinforcing rod 8 in a heat-shrinkable tube 6. The heat-meltable tube 7 is formed in a shape and size such that, for example, three tape core wires that are oval and arranged in a trapezoidal shape are inserted, and the reinforcing rod 8 is, for example, a semi-cylindrical shape Use one. The fusion-connected tape core wire is inserted into the heat-meltable tube 7 in a trapezoidal shape so that the fusion-bonding portion 4 is located at the center, and is heated by the heating mechanism 11.
[0025]
As shown in FIG. 2 (B-B), the heat shrinkable tube 6 is contracted / reduced in the inner diameter direction by the heating mechanism 11 to become a reduced diameter tube 6 ′, and the heat-meltable tube 7 is softened and melted. Thus, the molten adhesive resin 7 ′ fills the gap portion in the reduced diameter tube 6 ′. The tape core wire is bonded and integrated into the reduced-diameter tube 6 ′ by the molten adhesive resin 7 ′ while maintaining the trapezoidal arrangement together with the fusion spliced portion. That is, also in this case, it is possible to protect and reinforce the bare fibers without causing overlap between the tape core wires.
[0026]
3 and 4 are diagrams for explaining specific examples of the gripping mechanisms 12a and 12b. 3 is a perspective view of the gripping mechanism, FIG. 4A is a side view of the clamp released state, and FIG. 4B is a side view of the clamp closed state. In the figure, 20 is a clamp block, 20a is a concave groove, 20b is a support piece, 20c is a shaft support hole, 20d is a guide piece, 21 is a clamp base, 21a and 21b are gripping surfaces of the tape core wire, 22 is a clamp lid, 22a and 22b are clamp surfaces, 23 is a clamp shaft, 24 is an elastic member, 25a and 25b are magnets, and 26 is a clamp lever.
[0027]
The gripping mechanisms 12a and 12b are symmetrical, and the left gripping mechanism 12a is shown in the figure. The gripping mechanism 12 a is configured by disposing a clamp base 21 on a clamp block 20 and pivotally attaching a clamp lid 22 by a clamp shaft 23. The clamp block 20 has a concave groove 20a in which the clamp base 21 is disposed in the center, and a pair of support pieces 20b for forming a shaft support hole 20c are integrally provided on one side of the concave groove 20a. A guide piece 20d is integrally provided on the opposite side. Further, magnets 25a and 25b are embedded in the upper surface of the clamp block 20, and the clamp lid 22 is closed by suction.
[0028]
The clamp base 21 is assembled to the concave groove 20a of the clamp block 20 by fixing means such as screws. The upper surface of the clamp base 21 is a portion to be a gripping surface for fixing the tape core wire, and is formed as an integrally formed gripping surface having different angles, for example, two gripping surfaces 21a and 21b are chevron-shaped or C-shaped. Formed as follows. When three tape cores are used, a trapezoidal gripping surface corresponding to FIG. 2B is formed so as to obtain three gripping surfaces. The gripping surfaces 21a and 21b are formed so as to have different angles for each gripping surface so as not to be aligned in a single plane when a plurality of tape cores are gripped side by side.
[0029]
The clamp lid 22 is formed so that the clamp surfaces 22 a and 22 b that fit the grip surfaces 21 a and 21 b of the clamp base 21 have a V shape or a reverse C shape, and the clamp shaft 23 supports the clamp block 20. It is pivotally attached between the pieces 20b. An elastic member 24 such as rubber is affixed to the clamp surfaces 22a and 22b so that the tape can be clamped without scratching. The elastic member 24 may be provided on the holding surfaces 21a and 21b side of the clamp base 21 or may be provided on both sides.
[0030]
With the configuration as described above, with the clamp lid 22 of FIG. 4A opened, the tape cores 1 a and 1 b are placed on the gripping surfaces 21 a and 21 b of the clamp base 21. Next, as shown in FIG. 4B, by closing the clamp lid 22, the elastic members 24 press and hold the tape cores 1a and 1b on the gripping surfaces 21a and 21b. The clamp lid 22 is opened and closed by grasping an L-shaped clamp lever 26 attached and fixed to the upper surface. The clamp lid 22 is kept closed by the magnets 25a and 25b embedded in the clamp block 20, but the magnets 25a and 25b may be embedded on the clamp lid 22 side. Moreover, it can replace with fixation by a magnet and can also use the other fixing means using the engaging means and screw which were urged | biased with the spring.
[0031]
According to the above-described gripping mechanism, the tape cores 1a and 1b are held and fixed with a large gripping force by adding a wedge action by the gripping surfaces 21a and 21b having inclination angles in opposite directions and frictional contact by the elastic member 24. can do. As a result, even if the tape cores 1a and 1b are subjected to inward stress due to the reduced diameter of the protective member, the tape cores 1a and 1b are prevented from shifting on the gripping surface, and the bare fibers contact each other. Can be prevented. Further, after the tape cores 1a and 1b are placed following the gripping surfaces 21a and 21b, they can be easily fixed by simply closing the clamp lid 22 having a single structure, and the clamp lever 26 is pulled for removal. It can be done simply. As shown in FIG. 1 (B), this gripping mechanism is attached to the gripping mechanism fixing base 14 in a replaceable manner, and can be appropriately changed depending on the number of cores of the tape core wire, the number of wires used, and the like. It is preferable to leave.
[0032]
【The invention's effect】
As described above, according to the present invention, when reinforcing a fusion spliced portion where a plurality of optical fiber ribbons are arranged in parallel with each other by a protective member, the optical fibers contact each other by contraction of the protective member. This can prevent the occurrence of disconnection and the like.
[Brief description of the drawings]
FIG. 1 is a diagram for explaining the outline of a fusion splicing reinforcement method according to the present invention.
FIG. 2 is a diagram for explaining the operation of the fusion splicing reinforcement method according to the present invention.
FIG. 3 is a diagram illustrating a specific example of a fusion splicing reinforcement method according to the present invention.
FIG. 4 is a diagram for explaining the operating state of a specific example of the fusion splicing reinforcement method according to the present invention.
FIG. 5 is a diagram illustrating a conventional technique.
FIG. 6 is a diagram for explaining a conventional problem.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1,1a-1d ... Optical fiber tape core wire (tape core wire), 2 ... Bare fiber part, 3 ... Fiber coating | coated part, 4 ... Fusion splicing part, 5 ... Protection member, 6 ... Heat-shrinkable tube, 6 '... Reduced diameter tube, 7 ... Heat-meltable tube, 7 '... Melt adhesive resin, 8 ... Reinforcing rod, 9 ... Heating table, 10 ... Heater, 11 ... Heating mechanism, 12a, 12b ... Grip mechanism, 13 ... Heating mechanism fixing table , 14 ... gripping mechanism fixing base, 15 ... engagement pin, 20 ... clamp block, 20a ... concave groove, 20b ... support piece, 20c ... shaft support hole, 20d ... guide piece, 21 ... clamp base, 21a, 21b ... tape Core wire gripping surface, 22: clamp lid, 22a, 22b ... clamping surface, 23 ... clamp shaft, 24 ... elastic member, 25a, 25b ... magnet, 26 ... clamp lever.

Claims (2)

After fusion splicing of a plurality of optical fiber ribbons, the fusion splicing part is inserted and covered in a single heat-melting tube of a protective member, and then both sides of the fusion splicing part are gripped by a gripping mechanism. and, a fusion splicing reinforcing method of heat treatment of the protective member by the heating mechanism,
Fusion splicing reinforcing method characterized in that said plurality of optical fiber ribbon, to pressurized heat treatment is gripped by the gripping mechanism having two or more gripping surface which is integrally formed at different angles. The fusion splicing reinforcement method according to claim 1, wherein the gripping surface is formed by two C-shaped surfaces.

Images