JPS6258208A - Method for connecting and reinforcing multi-core optical fiber - Google Patents

Abstract

PURPOSE:To connect and reinforce safely and efficiently multi-core optical fibers without any risk of damaging the optical fibers so as to realize excellent optical fiber connection, by performing each work under a condition where the optical fibers are always grasped by means of clamping sections. CONSTITUTION:Firstly, a multi-core optical fiber core 1 is set to a clamping section 2. Then the coating 11' of the core 1 is removed from the side of the clamping section 2 with a coating remover 3 and the leading ends 12' of the optical fibers 12 of the core 1 are cut off so that the optical fibers 12 can have an even length. Then cores 1 regrasping operations are performed in such a way that the clamping section 2 on the left side is retreated along a rail 4 in the direction shown by the arrow, and then, caused to grasp the core 1. The clamping section 2 on the right also regrasp the core 1 in the same way. By retreating the clamping sections 2 in such a way, coating sections 11 of the cores 1 are newly exposed by a length (l) of about 5-10mm each. Thereafter, another reinforcing head carries a reinforcing material 5 and the material 5 covers and is stuck to the connecting section 13 of the optical fibers 12 and exposed coating sections 11 of the cores with a bonding agent, etc. Thus the optical fibers 12 are connected and reinforced.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention relates to a multi-core optical fiber such as a tape-like structure in which a plurality of optical fibers arranged parallel to each other at intervals are provided with a common coating and reinforcing layer. The present invention relates to a method for connecting and reinforcing optical fibers, and particularly to a method suitable for connecting and reinforcing optical fibers using automatic equipment.

(Prior Art and Problems to be Solved) Multi-core optical fibers are usually spliced and reinforced by the following steps: removing the coating, cutting the exposed optical fiber, fusion splicing, and reinforcing the spliced portion.

During such splicing and reinforcing work, the most important thing is to cut each optical fiber so that there are no irregularities on the end face.This allows the opposing optical fibers to be butted together, heated to high temperatures, pushed in, and fused. Connection will be made. If the cut optical fiber (+21) end faces are uneven as shown in Figure 2 C), the end faces cannot be butted together.
Even if heated and pushed, the optical fiber QZ
The connecting portion 03') of the connecting portion 03' becomes thicker or thinner. All of these will lead to an increase in connection loss. In the drawings, (1) indicates a multi-core optical fiber, and QD indicates a coating portion.

In addition, there are other factors that increase the amount of unevenness of the end faces of optical fibers. For example, if the adhesive force between the coating part OD of the multi-core optical fiber and the optical fiber 025 is weak, each light beam may be Fiber ab easily goes in and out, resulting in uneven end faces as shown in FIG.

In order to solve the above problems, a perspective view (A) and a cross section (B) are shown in Fig. 4 so that the end of the multi-core optical fiber is not bent and is not affected by distant bends. A terminal fixing jig (2) has been devised, which is attached to the multi-core optical fiber (1) before cutting and removed after connection.

However, considering the original purpose of the terminal fixing jig (6), it is desirable to set it as close to the end of the multi-core optical fiber as possible, and in reality, it is located at the very edge of the sheathing end or from the end of the sheathing. It is set at a position of 2 to 3 mm. On the other hand, during reinforcement after connection, the covering portion must be exposed for a long time.

That is, unless the reinforcing material overlaps the covering portion by at least 51 cm, usually by about 101 cm, it will not be able to bear the strength when tension is applied to the optical fiber and will easily peel off. Therefore, in the past, the fixing jig (6) was used as a multi-core optical fiber (
1), move the unstable multi-core optical fiber (with the glass part visible), set it in the reinforcing device, and heat it to integrate the reinforcing material, or fix it in the fixing jig (6). A method has been used in which another clamp is placed outside the optical fiber to grip the optical fiber (1) to facilitate reinforcement.

However, such a method involves the risk of damage due to bending, twisting, pulling, contact with other members, etc. since the glass portion is moved with the extremely fragile glass portion exposed.

(Means for Solving the Problems) The present invention solves the above-mentioned problems and provides a method for connecting and reinforcing multi-core optical fibers that is easy to handle and has a low risk of breakage. The clamp parts of the facing multi-core optical fibers are made movable in the axial direction, and when removing the coating from the multi-core optical fibers, it is removed from the side of the clamp parts, and after cutting and connecting the exposed optical fibers, Both clamp parts are alternately opened and moved back to grasp the coating part again, and then the newly exposed long coating part is overlapped with the reinforcing material to reinforce the connecting part of the optical fiber.

(Example) Figure 1) to (g) show the connection of the multi-core optical fiber of the present invention,
An explanatory diagram of the procedure of an embodiment of the reinforcing method is shown.

First, set the multi-core optical fiber (1) in the clamp part (2). (Figure A). At this time, the covering portion OD of the multi-core optical fiber (1) may or may not be removed. If the covering part OD has not been removed, use the covering remover (3) to remove the covering part (11
) is removed, and then the exposed tip (12') of the optical fiber 021 is cut using a cutting device to trim the end face (FIG. 3C). At this point, the clamp part (2) is set on a one-dimensionally movable rail (2), and the end faces of the opposing optical fibers (Q) are butted against each other to perform fusion splicing. (Figure 2).

Note that in the drawings, OE indicates a connecting portion.

Next, we move on to the re-gripping operation which is the key point of the present invention.

In this case, if both clamp parts ■ are left open at the same time, the multi-core optical fiber (1) may shift or come off, so when one clamp part opens, make sure that the other is closed. do. That is, as shown in the same figure (e), first open the left clamp part (2), move it back on the rail (2) in the direction of the arrow, re-grip the optical fiber core (1), and then As shown in the figure (to), open the right side clamp part ■ and move it back in the direction of the arrow as above to remove the optical fiber (1).
Re-grasp. By retreating in this manner, a new covering portion OD of about 5 to 10 mm is removed (exposed axis). At this time, make sure that the middle optical fiber +121 does not slacken.
Optical fiber (+2
1 maintains tension, making the next reinforcement work easier.

After that, another reinforcing head carries the reinforcing material ■ as shown in Figure 1 (G).
As shown in the figure, the connecting portion 01 of the optical fiber 07) and the coating portion OD 5 to IOw+s of the optical fiber core (1) are covered and bonded together with an adhesive or the like to be reinforced.

In the above embodiment, the clamp part was installed on the rail after the optical fiber cutting process, but the clamp part may be installed on the rail from the beginning, that is, from the coating removal process. Fusion splicing using a laser, gas burner, etc. as a heat source is common, but other methods such as a splicing method using a splicing agent may also be used. Furthermore, as an example of the reinforcing method, a method of sandwiching two reinforcing materials and fixing them with adhesive was exemplified, but the above-mentioned connection of the multi-core optical fiber of the present invention,
According to the reinforcing method, each operation is carried out with the multi-core optical fiber core always being held by the clamp part, so there is no risk of damage to the optical fibers, and connection and reinforcement can be carried out safely and efficiently. A good optical fiber connection can be achieved.

[Brief explanation of the drawing]

FIGS. 1(A) to 1(G) show explanatory views of the steps of an embodiment of the method for connecting and reinforcing multi-core optical fibers according to the present invention. Figure 2 (A) (B) and Figure 3 (H) (→ is an explanatory diagram of the uneven state of the end face of a multi-core optical fiber, and Figure 4 is a perspective view (A) and a cross-sectional view of the terminal fixing jig. 1...Multi-core optical fiber, II...Coating part, +2
...Optical fiber, 2...Clamp part, 4...Rail. 1b

Claims (2)

[Claims] (1) The clamp parts of the opposing multi-core optical fibers are movable in the axial direction, and when removing the coating from the multi-core optical fibers, it is removed from the side of the clamp part, and the exposed optical fibers are cut and removed. After the connection, both clamps are alternately opened and moved back to grasp the sheathing part again, and then the newly exposed long sheathing part is overlapped with the reinforcing material to reinforce the optical fiber connection part. A method for connecting and reinforcing multi-core optical fibers. (2) When retracting both clamp parts, a slight tension is applied to the multi-core optical fiber to reinforce the optical fiber while maintaining the tension state. Connection and reinforcement method for multi-core optical fibers.