JPH06123826A - Manufacture of coated optical fiber ribbon - Google Patents

Abstract

PURPOSE:To provide a manufacturing method of coated optical fibers ribbon whose array of optical fibers is hardly disordered even when the travel speed of the optical fibers is made fast. CONSTITUTION:The outside of plural optical fibers 1, arrayed in parallel on the same plane, is coated primarily with resin 3. At this time, the resin 3 is supplied to recessed parts 9 between adjacent optical fibers 1 without projecting out to form the primary coating. Then the resin 3 is cured to obtain a primary coated optical fiber ribbon, and the outside of the optical fiber ribbon is coated secondarily with the resin 7, which is cured. Then, the primary coating can be made thin, so even when the optical fibers are made to travel at high speed, their array is hardly disordered. Consequently, the travel speed of the optical fibers 1 is made fast to increase the productivity.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an optical fiber ribbon, which is formed by arranging a plurality of optical fiber strands in parallel in a plane and covering the outer circumference thereof in a tape form.

[0002]

2. Description of the Related Art A conventional optical fiber ribbon is shown in FIG.
As shown in (a), the outer circumferences of optical fiber strands A arranged in parallel in a plane are collectively covered with resin B (one layer)
As shown in FIG. 7 (b), there is one in which the outer periphery of the optical fiber element wire A is collectively covered with the resin B and then the outside thereof is collectively covered with the resin C (two-layered one). In the past,
In order to improve the lateral pressure characteristic of the optical fiber ribbon,
It has also been practiced to change the type of resin for the primary coating and the secondary coating.

Conventionally, in order to manufacture an optical fiber ribbon having a two-layer coating as shown in FIG. ． A plurality of optical fiber strands A are arranged in parallel in a plane by a strand feeder and fed to the primary coating device, and the outer side of the same primary coating device is collectively coated with resin B as shown in FIG. Cover). ． The primary coating resin B is cured by a primary curing device to obtain a primary coating tape core wire. ． The primary coated tape core wire obtained as described above is supplied to a secondary coating device, and the outside of the secondary coating device is secondarily coated with a resin C as shown in FIG. 7B. ． The secondary coated resin C is cured by a secondary curing device to form an optical fiber tape core wire.

[0004]

An optical fiber ribbon having a two-layer coating has the advantage that it is easy to arrange the optical fiber strands A in a row, but the conventional method for producing an optical fiber ribbon has the following advantages. There was such a problem.

.. Since the resin B of the primary coating is thick, the clearance between the optical fiber strand A and the inner peripheral surface of the outlet E of the die (FIG. 8) D of the primary coating device for extrusion coating the resin B must be increased. I won't. If this clearance is increased, the optical fiber strand A moves before the resin B is extrusion coated or before the resin B is cured after extrusion coating, and the optical fiber strand A is moved as shown in FIG. 7C. There was a problem that the arrangement of A was disturbed. The disturbance becomes more remarkable as the running speed of the optical fiber strand A is increased in order to improve the productivity of the optical fiber ribbon. ． If the resin B of the primary coating is thick, when the resin B is cured by a primary curing device and crosslinked, the stress caused by the contraction of the resin B becomes large, and the fiber strand A also causes the stress. It was sometimes misaligned. ． When the arrangement of the optical fiber strands A is disturbed as shown in FIG. 7C, the thickness of the obtained optical fiber tape core wire becomes thicker than the standard thickness, or the center position of each optical fiber strand A is disturbed. , It becomes difficult to make connector connection or welding connection. In extreme cases, those connections are not possible. ． Since the thickness of the primary coating changes as the running speed of the wire changes, it is difficult to keep the nipple size of the secondary coating device in an optimum shape at all times, and when the wire speed is started, the primary coating size becomes too large. , Sometimes the nipple of the secondary coating device was clogged.

An object of the present invention is to provide a method of manufacturing an optical fiber ribbon which is less likely to disturb the arrangement of the optical fiber wires even if the running speed of the optical fiber wires is increased.

[0007]

As shown in FIG. 1, a method of manufacturing an optical fiber ribbon according to the present invention supplies a plurality of optical fiber strands 1 in parallel in a plane to a primary coating device 2. In the coating device 2, the outside is collectively primary-coated with the resin 3, and the resin 3 is cured by the primary curing device 4 to form the primary coating tape core wire 5, and the primary coating tape core wire 5 is secondary-coated. In the manufacturing method of the optical fiber ribbon, the resin is supplied to the device 6, the outside of the device 6 is secondarily coated with the resin 7, and the resin 7 is cured by the secondary curing device 8. The primary coating of No. 3 is applied to the concave portions 9 between the adjacent optical fiber strands 1 so as not to project to the outside.

[0008]

In the method of manufacturing the optical fiber ribbon according to the present invention, the primary coating with the resin 3 is applied to the concave portions 9 between the adjacent optical fiber strands 1 so as not to project outside thereof, so that the primary coating layer is made of an optical material. It does not project outward in the thickness direction of the fiber strand 1. For this reason, it is not necessary to increase the clearance between the optical fiber element wire 1 and the inner peripheral surface of the exit of the die of the primary coating device 2, and the clearance can be almost zero. Therefore, the optical fiber element wires 1 are not displaced during extrusion coating, the arrangement of the optical fiber element wires 1 is not disturbed, and the thickness of the obtained optical fiber tape core wire does not become thicker than necessary. Further, since the amount of the resin 3 for the primary coating is small, the amount of shrinkage of the resin 3 when the resin 3 is heated or irradiated with ultraviolet rays to be crosslinked is small,
The stress caused by the contraction does not cause the optical fiber element wire 1 to be displaced. Further, since the thickness of the primary coating tape core wire becomes the thickness of the optical fiber element wire, the thickness of the nipple of the secondary coating device can be accurately specified. Therefore, when performing the secondary coating, the deflection in the thickness direction can be remarkably improved. Furthermore, since the thickness of the secondary coated tape core wire does not change even if the line wire speed is increased, the tape core wire can be stably covered at any speed.

[0009]

[Embodiment 1] A method of manufacturing an optical fiber ribbon according to the present invention will be described in detail with reference to the illustrated embodiment.

In the method of manufacturing an optical fiber ribbon according to the present invention, a plurality of optical fiber strands 1 shown in FIGS. 1 and 2 are arranged in parallel in a plane in a strand aligning and feeding device 11 and fed to a primary coating device 2. To do.

The strand aligning and supplying device 11 of FIG. 1 is arranged vertically and is a guide roll 1 for guiding each optical fiber strand 1.
2. The horizontal alignment roll 13 is arranged laterally to guide the optical fiber strand 1 from above and below, and the vertical alignment roll 14 is arranged vertically to guide the optical fiber strand 1 from left and right.

In the primary coating device 2, the outer sides of a plurality of optical fiber strands 1 arranged in parallel and supplied are collectively primary-coated with a resin 3 as shown in FIG. 3 (a). This primary coating fills the concave portions 9 between the adjacent optical fiber element wires 1 with the resin 3 so that the resin 3 does not protrude to the outside of the optical fiber element wire 1 (up and down in the thickness direction).

The primary coating may be applied to the outside of the optical fiber strands 1 at both ends in the arrangement direction of the plurality of optical fiber strands 1 as shown in FIG. Also in this case, the resin 3 for the primary coating is prevented from protruding in the thickness direction of the optical fiber element wire 1.

The resin 3 which is primarily coated as described above is cured by the primary curing device 4 to form the primary coated tape core wire 5.

Next, the primary coating tape core wire 5 is supplied to the secondary coating device 6, and in the same coating device 6, the primary coating tape core wire 5 is provided outside the secondary coating device 6.
As shown in (c) and (d), the resin 7 is secondarily coated, and the resin 7 is cured by the secondary curing device 8 to obtain the optical fiber ribbon 10.

In order to apply the primary coating as described above in the present invention, for example, the size of the die of the primary coating apparatus 2 is as follows. ． The thickness T of the through hole 22 of the die 21 shown in FIG.
In FIG. 4B, the dimension is slightly larger than the thickness (outer diameter) of the optical fiber strand 1. ． The width W of the through hole 22 of the die 21 (FIG. 4B) is n
In the case of the tape of the optical fiber element wire 1 of the book, the dimension is slightly larger than n times the outer diameter of the optical fiber element wire 1. Specifically, in the case of a 5-core optical fiber tape core wire using the optical fiber element wire 1 having an outer diameter of 0.25 mm, T = 0.255 to 0.
It is set to 260 mm and W = 1.260 to 1.270 mm.

In order to apply the primary coating as described above in the present invention, the following may be carried out. ． As shown in FIG. 4A, the distance L between the introduction portion 23 of the through hole 22 of the die 21 and the outlet 27 of the through hole 26 of the nipple 25 is set to be 6 to 10 mm (conventionally 1 to 3 mm). ,
The time for the optical fiber strand 1 to become compatible with the resin 3 is lengthened. ． As shown in FIG. 4B, the through holes 26 of the nipple 25 and the through holes 22 of the die 21 have the same thickness (width in the vertical direction) T, or the through holes 22 of the die 21 are made slightly smaller. .

By the way, conventionally, as shown in FIG. 8 (a), the reverse, that is, the thickness of the through hole G of the nipple F is the die D.
Was larger than the thickness of the through hole E. Also, in the past, FIG.
As shown in (b), the relationship between the thickness T ₁ and width W ₁ of the die D and the thickness T ₂ and width W ₂ of the nipple F is T ₁ > T ₂ and W ₁ > W.
_{Was 2} .

A primary coating was applied to the outside of the five optical fiber strands 1 by the primary coating device 2 shown in FIG. 4 to manufacture a 5-fiber optical fiber ribbon, and the five optical fiber strands 1 were manufactured.
Among these, the amount of deviation (the amount of arrangement deviation) of the centers of the other optical fiber strands 1 with respect to the line connecting the centers of the optical fiber strands 1 at both ends was 0.005 mm or less, which was stable. The production linear velocity at this time was 250 m / min.

In the present invention, the conventional primary curing device 4, secondary coating device 6, and secondary curing device 8 can be used as they are.

[0021]

[Embodiment 2] Embodiment 2 is a case in which the open coating die shown in FIGS. 5 and 6 is used as the primary coating device 2 to perform primary coating as shown in FIGS. 3 (a) and 3 (b).

In the open die 31 shown in FIG. 5, the resin supplied to the resin supply hole 32 is the resin reservoirs 33 and 34 and the branch passage 35.
Is supplied to the tapered passage 36 through which the fiber element wire 1 passes. This open dice 3
In No. 1, the angle of the passage 33 through which the optical fiber element wire 1 passes is important, and stable coating cannot be achieved when the speed is increased to 200 m / min unless the taper angle θ = 50 ° or less.

In the open die 41 shown in FIG. 6, the resin supplied to the resin supply hole 42 is supplied to the tapered passage 46 through the resin reservoirs 43 and 44 and a plurality of thin branch passages 45. The taper angle β of the passage 46 may be larger than the taper angle θ of the passage 46 of the open die 41 shown in FIG.

The primary coating was performed by using the open die 31 shown in FIG. 5, and the secondary coating was performed by the conventional secondary coating apparatus. In this case, the displacement amount of the optical fiber strands 1 was 0.007 mm up to 200 m / min.

[0025]

Example 3 In this example, a resin having a low Young's modulus was used for the primary coating and a resin having a high Young's modulus was used for the secondary coating. As a result, the lateral pressure characteristic of the obtained optical fiber ribbon was improved as compared with the case where the primary coating and the secondary coating were performed with only one kind of resin.

[0026]

In the method of manufacturing the optical fiber ribbon according to the present invention, the primary coating can be made very thin,
The arrangement of the optical fiber wires 1 is less likely to be disturbed, and the arrangement is hardly disturbed even when the optical fiber wires 1 are run at high speed. Therefore, the optical fiber strand 1 can be run at high speed to improve productivity.

[Brief description of drawings]

FIG. 1 is an explanatory plan view showing an example of an optical fiber tape core wire manufacturing apparatus used in a method for manufacturing an optical fiber tape core wire of the present invention.

FIG. 2 is a side view of the manufacturing apparatus in FIG.

FIG. 3 (a) is a front view showing an example of a primary coated tape core wire obtained during the production of the method for producing an optical fiber ribbon according to the present invention, and FIG. 3 (b) is another example of the same primary coated tape core wire. Is a sectional view showing an example of an optical fiber tape core wire manufactured by the method for manufacturing an optical fiber tape core wire of the present invention, and (d) is another example of the optical fiber tape core wire. Sectional drawing to show.

FIG. 4A is a vertical cross-sectional side view showing an example of a die used in the method for manufacturing an optical fiber ribbon according to the present invention;
(B) is a front view of the die.

FIG. 5A is a vertical sectional side view showing another example of a die used in the method for manufacturing an optical fiber ribbon according to the present invention;
(B) is a front view of the die.

FIG. 6A is a vertical sectional side view showing still another example of a die used in the method for manufacturing an optical fiber ribbon according to the present invention;
(B) is a front view of the die.

FIG. 7A is a cross-sectional view of an optical fiber tape core wire having a single coating layer manufactured by a conventional method for manufacturing an optical fiber tape core wire, and FIG. 7B is an optical fiber tape core having two coating layers. Sectional drawing of a line, (c) is a sectional view of the state where the optical fiber core wire of the optical fiber tape core wire with a two-layer coating layer has shifted position.

FIG. 8A is a vertical sectional side view of a die used in a conventional method for manufacturing an optical fiber ribbon, and FIG. 8B is a front view of the die.

[Explanation of symbols]

 1 is an optical fiber wire "2 is a primary coating device 3 is a resin 4 is a primary curing device 5 is a primary coating tape core wire 6 is a secondary coating device 7 is a resin 8 is a secondary curing device 9 is a recess

Claims (1)

[Claims] 1. A plurality of optical fiber strands 1 are arranged in parallel in a plane and supplied to a primary coating device 2, and the same primary coating device 2 is provided.
In the above, the outside is collectively covered with the resin 3 and the resin 3 is cured by the primary curing device 4 to form the primary coating tape core wire 5, and this primary coating tape core wire 5 is supplied to the secondary coating device 6. In the method for manufacturing an optical fiber ribbon, the outer side of the secondary coating device 6 is secondarily coated with a resin 7 and the resin 7 is cured by a secondary curing device 8. A method for producing an optical fiber ribbon, wherein a coating is applied to a recess 9 between adjacent optical fiber strands 1 so as not to project to the outside.