JPS5974518A - Connecting method of multiple cores of optical fiber core by blanket arc welding - Google Patents

Abstract

PURPOSE:To connect plural optical fiber strands collectively with arc welding, by fixing optical fiber strands after a secondary coating is removed to expose plural optical fiber strands and cutting them to true up connection end faces. CONSTITUTION:In the state where a secondary coating 2 is removed in the end part of a tape-shaped optical fiber core 1 to expose plural optical fiber strands 3, end face positions of strands 3 are normally irregular. A terminal reinforcing tool 4 is molded to be laid across exposed parts of strands 3 and the secondary coating 2 to fix them to each other, and optical fiber strands 3 are cut to an even length to true up their end face positions. Optical fiber cores 1 and 1' where end face positions of strands are trued up in this manner are allowed to face each other, and electricity is discharged from discharge electrodes 5 and 5' between which the gap of end faces is interposed as a discharge space, thus connecting plural optical fiber strands 3 collectively with arc welding.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for simultaneously fusion splicing multiple optical fibers.

Conventionally, many fusion splicing methods for optical fiber core wires have been developed, but when fusion splicing multi-core optical fiber core wires using these methods, if fusion splice is performed for each strand, one core It is effective to use a fusion splicing method that can simultaneously perform fusion splicing of the wire fibers to the wires and all at once. In this batch fusion splicing method, the end face of each strand must be mirror-cut as in normal fusion splicing), and
All end faces of the strands to be removed must be aligned. If the positions of the end faces are uneven, the gaps between the butt edges will be uneven, and batch fusion splicing cannot be performed. However, conventionally, even if you try to cut multiple strands of strands at once to align them, the strands of strands will be doubled due to the bending and tension applied to the strands during cutting.
The next time the sheathing was removed, or one day, after cutting, the curved and twisted cores of the core would shift from each other, making it impossible to align the end faces accurately.

An object of the present invention is to provide a method for fusion splicing a plurality of optical fiber strands at once by preventing misalignment of the strands when cutting and aligning the strands after that. The structure is such that, in a method of fusion splicing by butting opposing optical fiber cores against each other, the secondary coating of the optical fiber cores is removed to expose a plurality of optical fiber strands. After that, the strands are fixed, the connection end faces are trimmed, and the strands are butted against each other and fusion spliced all at once.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the method for simultaneously fusion splicing multiple optical fibers according to the present invention will be described in detail based on examples.

FIGS. 1 to 6 are explanatory diagrams of an embodiment of the method of the present invention. As shown in FIG. 1, the optical fiber used in this embodiment (the core wire is a tape-shaped optical fiber core wire 1 in which a plurality of optical fiber strands 3 are arranged in a row).
The secondary coating 2 at the end of the optical fiber core 1 is removed to expose a plurality of optical fiber strands 3. Normally, the glue exposed from the secondary coating of this optical fiber core #Jii 1! 3
The protruding lengths of the wires 3 are different, and the positions of the end faces of the wires 3 are irregular. An end reinforcing device 4 is molded onto a portion spanning the exposed portion of the twisted cable 3 and the secondary coating 2 (see FIG. 2). The molded terminal reinforcing tool 4 is a bare wire 3f:
Since they are fixed to each other and the strand 3 and the secondary coating 2 are fixed together, there is no possibility that the strand 3 is pulled out from the secondary coating 2 when the strand 3 is cut, or that the optical fiber core πφ is removed after cutting.
] The strands 3 are prevented from shifting from each other due to the bending. Further, the terminal reinforcing member 4 may be fixed to a portion spanning the exposed portion of the multi-strand wire 3 and the secondary coating 2 by adhesive instead of using a mold. Next, the plurality of optical fiber strands 3 are trimmed and their end faces are aligned (see Fig. 3).

Then, the optical fiber 6 with the end face position of the strand 3 aligned 1,1
' against each other (see Figure 4).

At this time, the positions of the end faces of the wires 3 are maintained in a uniform state by the terminal reinforcing tool 4, and it is possible to match the end face gaps of each strand 3 uniformly (Z).

As a method for securing this end face gap, it is possible to use a stopper abutment or a method a in which the strands 3 abut against each other. Next, the discharge electrodes 5 sandwich the plurality of end face gaps aligned 1-2 and abutted against each other as a discharge space.
, 5' to fuse the plurality of optical fiber strands 3 at once.
and a push plate 8. The pedestal 7 has a flat plate portion on which the strands 3 are arranged, and is also provided with presses 1 to 8 for pressing the strands 3. The push plate 8 is screwed into the tightening port 9 [2 and supported on the pedestal 7]; by the rotation of the tightening bolt 9, the push plate 8 is lowered and holds the plurality of wires 3 on the pedestal. A rubber plate 30°] 1 with high frictional resistance is provided on the flat plate part of the pedestal 7 and the pressing surface of the push plate 8. , which increases the fixed effect.

In this way, in the multi-fiber batch sub-single connection method of optical fiber core wires of the present invention, the terminal reinforcing tool 4 fixes the plurality of optical fibers 3 to each other and connects the fibers 3 with the secondary coating. 2 and 7 are fixed in one piece with gold. Therefore, the element 1 seen in the cut
Therefore, the optical fiber core wires 1, 1' are fusion spliced by the method of the present invention without the end face positions of i13 being irregular.
As shown in Figure 6(a) (1)), a specific strand 3
A good fusion splice can be obtained without adding any slack or tension υ. f^1. The optical fiber core 1 used in the above example was a multi-core tape-shaped optical fiber core 1 in which a secondary MM2 was integrally applied to a plurality of optical fiber strands 3. Not limited to this example, a plurality of single optical fiber cores each having a secondary coating 2 applied to each optical fiber strand 3 are bundled,
It may be integrated with the terminal reinforcing tool 4 and fused and spliced all at once in the same manner as the above method. Furthermore, when the pressing force fixing tool 6f shown in FIG. 7 is used, a plurality of wires 3 can be fixed together as in the above embodiment, so the wires 3 can be cut and aligned to uniform lengths. It is possible to perform bulk fusion splicing. After the batch fusion splicing, the pressing fixture 6 can be removed.
When covering the exposed wire 3 with a reinforcing material, by selecting a reinforcing material that has a small difference in coefficient of expansion from the wire 3 or the secondary coating 2, reliability can be further improved.

As described above in detail based on the embodiments, according to the present invention, it is possible to fusion splice a plurality of optical fibers at once with their end faces aligned accurately, resulting in highly reliable fusion splicing. is obtained.

[Brief explanation of drawings]

1 to 6 (R) and (b) respectively relate to an embodiment of the method of the present invention. FIG. 1 is a front view of the optical fiber core wire;
Fig. 2 is a front view of the molded core of the terminal reinforcing device, Fig. 3 is a front view of the cut and aligned core wire, and Fig. 4 is a front view of the optical fiber 6 ties that are butted against each other. Figure 5 is a front view of the core wires that are collectively fused and spliced, Figure 6 (a)
Figure 6(b) is a front view of the core wire after batch fusion splicing.
Figure (a) is a side view, and Figure 7 is a front view of a suppression fixture used in another method of fixing strands. In the drawing, 1.1' is the optical fiber core, 2 is the secondary coating, 3I is the bare optical fiber, 4 is the terminal reinforcement, 5.5' is the discharge electrode, 6 is the suppression fixture, and 7 is the pedestal. , 8 is a push plate, 9 is a tightening screw, and 10.11 is a rubber plate. Special W “Applicant Patent Attorney Mr. Mitsuishi (and 1 other person)

Claims (1)

[Claims] (1) In a method of fusion splicing opposing optical fiber cores by abutting them against each other, the secondary coating of the optical fiber cores is removed to expose a plurality of optical fibers. After that, the strands are fixed, the connection end faces are cut and aligned, and each strand is butted against each other to be fusion spliced all at once. . (2. A method for collectively fusion splicing multiple optical fibers according to claim 1, characterized in that the strands are fixed by adhesive or molding. (3) Claim 1. A multi-fiber batch fusion splicing method for optical fiber cores, characterized in that the strands are pressed and fixed by a fixture.