JPH063485B2 - Reinforcement method of optical fiber connection - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to a method for reinforcing optical fiber splices connected by fusion means.

(Prior Art) As is well known, when splicing optical fibers in the longitudinal direction, a coating removal portion is formed by removing a coating layer from the end of a pair of coated optical fibers, and the coating removal is performed. The portions are cut into appropriate lengths, and then the tips of the coating removal portions (bare fibers) are abutted against each other while being heated by discharge heating, laser heating, or the like, and fusion-bonded.

FIG. 1 shows an optical fiber splicing portion fusion-spliced as described above. In FIG. 1, 1A and 1B are coated optical fibers forming a pair, 2A and 2B are these coating layers and 3
A and 3B are coating removal parts.

The optical fiber connection part (including the coating removal part) is generally reinforced by a coating means in order to guarantee the strength after the coating removal. At present, a split mold 4 as shown in FIG. 1 is used. After mounting over the ends of the coating layers 2A, 2B,
For example, a thermosetting resin 6 is injected into the molding die 4 through an injection means such as a syringe 5, and the molding die 4 is heated to cure the resin 6.

As a result, the reinforcing coating layer 7 made of the resin 6 is formed on the outer periphery of the optical fiber connecting portion as shown in FIG. The burr 8 is generated, and the burr 8 causes the following problems.

That is, the burr 8 is removed at the connection work site through scissors, a razor, etc., but the removal work requires much labor and time, and the reinforcing coating layer 7
Since the diameter of the burr 8 is small, the same layer 7 may be damaged, and the burr 8 may not be removed sufficiently. Especially, when the burr 8 is left unremoved, the coated optical fiber may be formed after the core is formed or a unit is formed. Can not be assembled properly, for example, it is caught in a twisting die or is broken.

(Object of the Invention) In view of the above problems, the present invention is to provide a method for forming a reinforcing coating layer of an optical fiber connecting portion on a smooth surface without burrs.

(Structure of the Invention) The present invention forms a coating removal portion by removing a coating layer from the end portion of a pair of coated optical fibers, and after the tips of these coating removal portions are abutted against each other and fusion-bonded, In a method of reinforcing an optical fiber splicing portion, in which a resin-made reinforcing coating layer is formed on the outer periphery of a coating removal portion in a connected state, a die-type coating device is movable on the outer periphery of the one coated optical fiber over the coating removal portion in a connected state. Multiple, and
The coating removing section is arranged in the axial direction and provided, and after the uncured resin is accommodated in each coating device, the coating removal section in the connected state and these coating devices are arranged in the axial direction of the coating removal section. By applying relative movement along it, uncured resin is applied to the outer periphery of the coating removal portion in the connected state, and
It is characterized in that the uncured resin is cured to form a reinforcing coating layer.

(Embodiment) Next, an embodiment of the present invention will be described with reference to FIGS.

In FIGS. 3 and 4, 1A and 1B are paired coated optical fibers, 2A and 2B are coating layers thereof, 3A and 3B are coating removal portions, and the tips of these coating removal portions 3A and 3B are the first. As in the case of the figure, they are fusion-spliced via known means.

In the present invention, when reinforcing the optical fiber connection portion, first, the coating layers 2A and 2B of the coated optical fibers 1A and 1B are set to 1
It is held by the pair of clamps 9A and 9B, and in the clamped state, the coating removing portions 3A and 3B are held in a tight state without slack.

Next, dice-type coating devices 10A and 10B are provided on the outer circumference of the one coated optical fiber 1B above and below.

The coating devices 10A and 10B have a die portion 11 and a resin accommodating portion 12, and the split mold structure thereof can be disassembled into two or more pieces.

Therefore, when it is mounted on the outer circumference of the coated optical fiber 1B as described above, the coating devices 10A and 10B are applied to the outer circumference of the coated optical fiber 1B in a disassembled state, and these split mold portions are coupled to each other.

The coating devices 10A and 10B are supported by an adjusting table (stage) 13 so that they can be adjusted in the front-rear direction and the left-right direction with respect to the coated optical fiber 1B having an axis line in the vertical direction. These coaters 10A and 10B set on the outer periphery of 1B are centered via an adjusting table 13 so that the center of the die part 11 and the axis of the coating removing parts 3A and 3B coincide with each other.

Further, the adjusting table 13 supporting each of the coating devices 10A and 10B has a guide 14 parallel to the coating removing parts 3A and 3B, a wire 15 connected to the coating device 10, and a wire 15 for winding and unwinding the wire 15. Drum 16
A, the sheave 16B, a handle 17 provided on the drum 16A, and the like are used to move in the axial direction of the coating removing units 3A and 3B.

In this state, the uncured (liquid) resin 6 is housed in the resin housing portion 12 of the coating device 10A, 10B, respectively, and then the coating device 10A, 10B is covered by the operation of the handle 17 while maintaining the order. The coating device 10A moves from the optical fiber 1B side to the coated optical fiber 1A side, and at the time of the movement.
For 10B, the uncured resin 6 is applied to the outer periphery of the coating removal portions 3A and 3B.

That is, in FIG. 4, an uncured reinforcing coating layer 7 that is to be subjected to a curing treatment is formed.

The resin 6 forming the reinforcing coating layer 7 is a thermosetting resin such as silicone resin (including silicone rubber), epoxy resin, urethane resin, unsaturated polyester resin,
Appropriate ones are selected from light (ultraviolet) curable resins such as epoxy acrylate and urethane acrylate.

The uncured reinforcing coating layer 7 formed as described above is the fourth
It is cured immediately by the curing means shown.

In FIG. 4, assuming that the resin 6 described above is photo-curable, ultraviolet lamps 19A and reflectors 19B are provided as curing means 18 for the resin 6 on both sides of the uncured reinforcing coating layer 7, and the curing means 18 is used. The reinforcing coating layer 7 is cured by receiving the curing energy.

On the other hand, when the resin 6 is thermosetting, the curing means 18
As a heater, a heater such as an electric heater is provided around the uncured reinforcing coating layer 7, whereby the layer 7 is cured.

The outer diameter of the coating removal portion 7 formed as described above is finished to be almost the same as the inner diameter of the die portion 11 by applying the resin twice through both coating devices 10A and 10B, so that the reinforcing coating layer 7 is 1 The outer diameter of the coating layers 2A and 2B is almost the same as that of the resin coating step.

In the above-described embodiment, the coating removing units 3A and 3B are in a stationary state and the coating devices 10A and 10B are moved. However, the reverse coating devices 10A and 10B are in a stationary state, and the coating removing units 3A and 3B are set in the stationary state. Even if they are moved in the axial direction, the same resin application as above can be performed.

The number of the coating devices may of course be increased to three or more if necessary, but it is not desirable to increase the number insignificantly, and it is practical to set the number of the coating devices to two or three. Is.

FIG. 5 shows the reinforcing coating layer 7 formed as described above.

The reinforcing coating layer 7 has a smooth surface and does not generate burrs as in the conventional method, and therefore does not have various problems caused by burrs.

(Effects of the Invention) As described above, according to the method of the present invention, uncured resin is applied to the outer periphery of the coating removal portion by relative movement between the coating removal portion in the connected state and the die-type coating device, and this is cured. Since the reinforcing coating layer is formed, not only the optical fiber connecting portion can be reinforced, but also the reinforcing coating layer can be finished to have a smooth surface without burrs, and since the resin coating is performed by a plurality of coating devices, the coating can be performed once. By the coating process, the accuracy of the outer diameter of the reinforcing coating layer can be increased, and the reinforcing coating layer can be obtained which can be omitted and the unit can be favorably formed later.

[Brief description of drawings]

FIG. 1 is an explanatory view of a conventional method, FIG. 2 is a sectional view of an optical fiber connecting portion reinforced by the same method, and FIGS. 3 and 4 are explanatory views schematically showing one embodiment of the method of the present invention. FIG. 5 is a cross-sectional view of an optical fiber connection portion reinforced by the above method. 1A, 1B ... Coated optical fiber 2A, 2B ... Coating layer 3A, 3B ... Coating removal part 6 ... Resin 7 ... Reinforcing coating layer 10A, 10B ... Coating device 18 ... Curing means

Front page continuation (72) Akihiro Otake, 6th Yawata Kaigan Dori, Ichihara-shi, Chiba Furukawa Electric Co., Ltd. Chiba Electric Wire Works (72) Kenichi Komura 6 Hachiman Kaigan Dori, Ichihara, Chiba Furukawa Electric Co., Ltd. Chiba Electric Wire Works (72) Inventor Masatoshi Onishi, Tokai-mura, Naka-gun, Ibaraki Prefecture, Shirahone 162 Shirane, Ibaraki Telecommunications Research Institute, Nippon Telegraph and Telephone Public Corporation (72) Inventor, Haibara Tokai-mura, Naka-gun, Ibaraki Prefecture 162 Shirakuji, Shirane, Japan Telegraph and Telephone Public Corporation Ibaraki Telecommunications Research Institute

Claims (2)

[Claims] 1. A coating-removed portion is formed by removing a coating layer from the end portion of a pair of coated optical fibers, the tips of these coating-removed portions are abutted against each other and fusion-bonded, and then the coating in the connected state. In the method of reinforcing an optical fiber connecting portion to form a resin-made reinforcing coating layer on the outer periphery of the removed portion, a plurality of die-type coaters that are movable over the coating removal portion in the connected state are provided on the outer periphery of the one coated optical fiber, and The coating removing section is arranged in the axial direction and provided, and after the uncured resin is accommodated in each coating device, the coating removal section in the connected state and these coating devices are arranged in the axial direction of the coating removal section. By applying relative movement along it, uncured resin is applied to the outer periphery of the coating removal portion in the connected state, and
A method for reinforcing an optical fiber connecting portion, which comprises curing the uncured resin to form a reinforcing coating layer. 2. The method for reinforcing an optical fiber connecting portion according to claim 1, wherein the reinforcing coating layer is formed of either a photocurable resin or a thermosetting resin.