JPH06157077A - Production of type core wire of optical fiber - Google Patents

Abstract

PURPOSE:To stabilize transmission characteristics by traveling plural core wires of optical fiber in a row in a fiber introduction part charged with an inert gas, continuously coating the core wires with a resin and curing by UV. CONSTITUTION:An inert gas such as an N2 gas or an Ar gas in introduced from an gas inlet 531 to an optical fiber introduction part 57 and discharged from a gas outlet 512. The inert gas is introduced so that the interior of an optical fiber introduction part 57 is not made constantly negative pressure by a differential pressure gauge 59 to isolate admixture of air. To the optical fiber introduction part 57 in this state, core wires 3 of optical fiber arranged in a row and bundled in a beltlike state are successively introduced. The core wires of optical fiber are coated with a resin 6 such as a UV-curing resin by a resin coating chamber 56 and taken out from an outlet 12 at a flange part of a die 52. Successively the coated core wires of optical fiber are passed through a resin curing furnace, cured and wound to give tape core wires 8 of optical fiber having stable transmission characteristics, mechanical characteristics and temperature characteristics.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical fiber ribbon and, more particularly, to the inside and outside of a coating resin when a plurality of optical fiber strands are arranged in parallel while being continuously extruded for resin coating. The present invention relates to a method of manufacturing an optical fiber ribbon which can obtain the same curing rate.

[0002]

2. Description of the Related Art Generally, an optical fiber has a remarkably different physical or mechanical characteristic from that of a conventional copper conductor. Various characteristics and easy handling. However, in the case of making a cable, if a large external force such as lateral pressure is applied to the optical fiber strand, a slight bending (microbending) occurs in the optical fiber core wire, which increases the transmission loss. Need to be considered. Considering this point, there is a spacer type as the structure of the optical fiber cable. This spacer type fiber cable
The structure is such that the mechanical characteristics of the cable are improved, and particularly high reliability against lateral pressure is obtained.

The optical fiber strand is a glass fiber that is drawn from an electric furnace and spun in an optical fiber drawing device, and is subjected to a primary coating and a secondary coating. In this state, the surface of this optical fiber strand is easily scratched and its mechanical strength is weak.Therefore, a single-core optical fiber core made of resin coating or multiple optical fiber strands arranged in parallel. To form a multi-fiber optical fiber ribbon which is lined up with and coated with a resin to form a tape.

This optical fiber tape core wire is conventionally shown in FIG.
It is manufactured online by the optical fiber ribbon manufacturing apparatus 100 as shown in FIG. That is, a plurality of pieces (for example, four pieces) supplied from the supply device 110
Six (eight, eight, etc.) optical fiber strands (colored for selection in advance) 120 are applied to a coating head 140 that coats a resin on the belt-shaped optical fiber core line 120 via a guide member 130. Supplied.

A coating head 140 for coating the belt-shaped optical fiber core wire with a resin, which is used in the belt-shaped optical fiber core wire manufacturing apparatus 100, has a structure as shown in FIG. That is, it is composed of a holder 141 formed in a cylindrical shape, a die 142 attached to the holder 141, and a nipple 143.
The die 142 is formed in a cylindrical shape, and has a flange 144 at one end. The die 142 is fitted to the tip of a cylindrical holder 141, and the flange portion 144 of the die 142 is attached to the holder 141 by bolts (not shown).

The nipple 143 is formed in a cylindrical shape and its tip is narrowed in a funnel shape, and the opening shape of the tip is a substantially elliptical shape suitable for bundling a plurality of optical fiber element wires 120 in parallel. Is formed in. Also, the nipple 14
3, a flange portion 145 is provided at the rear end, and the inside of the nipple 143, that is, the optical fiber introduction portion is hollow, and a hollow portion 147 is formed. The cavity 147 is filled with air. The nipple 143 is fitted to the rear end of the cylindrical holder 141, and the flange portion of the nipple 143 is tightly attached to the holder 141 with a bolt (not shown). A space is formed between the die 142 and the nipple 143, and this space covers the plurality of optical fiber element wires 120 bundled in a strip shape (for example, U
A resin coating chamber 146 filled with the V-curable resin) 150 is formed. Therefore, the inside of the die 142 is formed in a shape that matches the shape of the tip of the nipple 143.

Then, on the upper side wall of the holder 141,
Resin 15 covering a plurality of optical fiber element wires 120 aligned in parallel by the nipple 143 and bundled in a strip shape
A resin supply port 1410 for introducing 0 is provided, and the resin supply port 1410 communicates with the resin coating chamber 146. Further, the lower side wall of the holder 141 is manufactured at the start of manufacturing the strip-shaped optical fiber core wire in order to prevent the plurality of optical fiber strands 120 bundled in a strip from being covered with resin containing bubbles. Is provided with a resin overflow port 1411 for discarding the resin charged in the initial stage, and the resin supply port 1410 communicates with the resin coating chamber 146. When the resin 150 for coating is introduced from the resin supply port 1410, the resin coating chamber 146 is filled with the resin 150.

A plurality of optical fiber strands 120 aligned in parallel by the nipple 143 and bundled in a strip form are
2, which is located approximately in the center of the resin coating chamber and is coated with resin when passing through the resin coating chamber 146 filled with the resin 150,
It is pulled out from the flange side outlet of the die 142.

As described above, in the coating head 140, a plurality of (for example, four, six, eight, etc.) optical fiber strands 120 are arranged on the UV curable resin 150.
Are coated as shown in FIG. After that, UV (ultr
In a resin curing furnace 160 such as an abiolet) furnace, the curable resin 1 coated on the plurality of optical fiber strands 120
The optical fiber tape core wire 180 having a plurality of cores (4 cores, 6 cores, 8 cores, etc.) is manufactured by curing 50, and is taken up by a take-up device 190 and taken up by a take-up device 200.

[0010]

In manufacturing the optical fiber tape core wire 180, a plurality of optical fiber wires 120 whose surfaces have been colored in advance are arranged, and the plurality of optical fiber wires 120 are collectively packaged. UV curable resin 15
0 is extrusion coated with an extruder. The UV curable resin 150 is made of an acrylate resin such as an acrylic acid salt, an acrylic acid ester, an acrylic acid resin, or the like, and has a property of being cured and contracted toward the center when irradiated with ultraviolet rays.

The optical fiber tape core wire 180 manufactured in this manner is housed in the housing groove formed in the longitudinal direction of the strength member on the outer peripheral surface of the strength member (tension member), and is wound and pressed by the holding tape. An optical fiber cable is manufactured by covering an outer sheath (sheath) on the press-winding tape.

The UV-curable resin 150 is cured by irradiating it with ultraviolet rays (UV). The UV-curable resin 150 contains O ₂ contained in the air.
When it comes into contact with gas, the curing reaction is hindered and the curing reaction rate decreases.

In the coating head 140 of the conventional optical fiber ribbon manufacturing apparatus 100, the inside of the optical fiber introducing portion of the nipple 143 is hollow and filled with air, and a plurality of optical fibers are introduced from the optical fiber introducing portion. When the wires 120 are arranged in parallel and are collectively covered with a tape material,
When the paralleled optical fiber strands 120 pass through the optical fiber introducing portion, the UV curable resin 1 is kept between the optical fiber strands or with a small amount of air trapped on the surface of the optical fiber strands.
50 is coated and cured by the light of the UV lamp of the resin curing furnace 160.

Therefore, in the conventional optical fiber ribbon, the UV curable resin is cured by the O ₂ gas contained in a small amount of air between the optical fiber strands or in the surface of the optical fiber strands. There is a problem that the curing reaction rate is reduced inside the UV curable resin 151 coated on the optical fiber strand due to the inhibition of the reaction, and the production rate of the optical fiber ribbon is limited.

Further, in the conventional optical fiber ribbon, the U ₂ gas is contained by the O ₂ gas contained in a small amount of air between the optical fiber strands or on the surface of the optical fiber strands.
Since the curing reaction of the V-curable resin is inhibited, the curing reaction rate decreases at the inside 151 of the UV-curable resin coated on the optical fiber strand, and the curing rate of the inside 151 of the coated UV-curable resin is outside 152. Since the curing rate is lower than the curing rate, there is a problem that the transmission characteristics, mechanical characteristics, and temperature characteristics of the optical fiber ribbon become unstable.

According to the present invention, a plurality of optical fiber strands are arranged in parallel while running and continuously extruded to obtain resin, and the same curing rate is obtained in the inside and outside of the coated resin. Without limiting the production speed
It is an object of the present invention to provide a method for manufacturing an optical fiber tape core wire that can obtain an optical fiber tape core wire with stable transmission characteristics, mechanical characteristics, and temperature characteristics.

[0017]

In order to achieve the above object, in the method for manufacturing an optical fiber ribbon according to the present invention, a plurality of running optical fiber strands are arranged in parallel and filled with an inert gas. After running in the fiber introducing portion of the nipple, UV resin is continuously coated in a tape shape in the resin coating chamber of the coating head to be UV cured.

[0018]

The inert gas such as N ₂ gas and Ar gas is introduced into the fiber introduction portion of the nipple of the coating head so as not to be a negative pressure. Into the fiber introducing portion of this nipple, a plurality of running optical fiber element wires are introduced in parallel in a tape shape. The tape-shaped optical fiber strands running in an inert gas such as N ₂ gas or Ar gas are continuously coated with UV resin in the resin coating chamber of the coating head after being output from the nipple. The coated UV resin is irradiated with UV to be cured.

[0019]

EXAMPLES Examples of the method for manufacturing an optical fiber ribbon according to the present invention will be described below. FIG. 1 shows an embodiment of a method for manufacturing an optical fiber ribbon according to the present invention.

In the figure, reference numeral 1 is an optical fiber ribbon manufacturing apparatus for manufacturing a tape ribbon from a plurality of optical fiber strands. Reference numeral 2 is a supply device for feeding out the optical fiber element wire 3 wound around a drum in a constant running. The supply device 2 is provided with the number of drums of the optical fiber element wires 3 corresponding to the number of core wires for manufacturing the tape core wires.

Reference numeral 4 denotes a guide member which guides a plurality of optical fiber element wires 3 supplied from the supply device 2 by arranging them in a flat shape. Reference numeral 5 is a coating head, and a plurality of (for example, four, eight, etc.) optical fiber strands 3 arranged in a flat shape guided from the guide member 4 are provided with an acrylate, an acrylate, an acrylic acid. A UV curable resin such as an acrylate resin such as a resin is extrusion-coated. This UV-curable resin has a property of being cured by irradiation with ultraviolet rays, and usually has a property of being cured by 90% or more just by irradiating for about 1 second after coating the UV-curable resin. In this coating head 5, a plurality of colored optical fiber strands 3 are arranged side by side, and a transparent or semitransparent matrix material (liquid) is attached to the outer periphery thereof.

The coating head 5 used for the belt-shaped optical fiber manufacturing apparatus 1 for coating a resin on the belt-shaped optical fiber has a structure as shown in FIG. That is, the holder 51 formed in a cylindrical shape
And a die 52 attached to the holder 51 and a nipple 53. The die 52 is formed in a cylindrical shape and has a flange portion 54 at one end. The die 52 is fitted to the tip of a cylindrical holder 51, and the flange portion 54 of the die 52 is attached to the holder 51 with a bolt (not shown).

The nipple 53 is fitted to the rear end of the cylindrical holder 51, and the flange portion of the nipple 53 is tightly attached to the holder 51 with a bolt (not shown). A space is formed between the die 52 and the nipple 53, and this space is filled with a resin (for example, a UV curable resin) 6 that coats a plurality of optical fiber element wires 3 bundled in a band shape. A resin coating chamber 56 is formed. Therefore, the inside of the die 52 is formed in a shape that matches the shape of the tip of the nipple 53.

The nipple 53 is formed in a cylindrical shape and its tip is narrowed in a funnel shape. The opening shape of the tip is a substantially oval shape suitable for bundling a plurality of optical fiber element wires 3 in parallel. Is formed in. A flange 55 is provided at the rear end of the nipple 53,
The inside is hollow, and this cavity forms the optical fiber introducing portion 57. This optical fiber introducing section 57
Is a place where a plurality of optical fiber strands 3 are guided and parallelized. Reference numeral 57 is a lid for sealing the optical fiber introducing portion 57. That is, air is prevented from entering from the optical fiber introducing side inside the optical fiber introducing portion 57. This prevents the inflow of air into the optical fiber introducing portion 57 from the optical fiber introducing side.

Reference numeral 531 is a gas inlet, which is N ₂ gas or Ar.
It is an inlet for introducing an inert gas such as gas into the optical fiber introducing portion 57. A gas outlet 532 is an outlet for removing an inert gas such as N ₂ gas or Ar gas introduced into the optical fiber introducing portion 57. Reference numeral 512 is a gas outlet provided in the holder 51 that communicates with the gas outlet 532. An inert gas such as N ₂ gas or Ar gas is supplied from the gas introduction port 531 so that the inside of the optical fiber introduction portion 57 does not have a negative pressure. That is, the optical fiber introducing section 5
The inside of 7 is filled with an inert gas such as N ₂ gas or Ar gas. The pressure inside the optical fiber introducing portion 57 is controlled by the differential pressure gauge 59 so as not to become a negative pressure due to the difference between the pressure inside the optical fiber introducing portion 57 and the air pressure. The differential pressure gauge 59 is adapted to introduce the pressure derived from the gas pressure introducing port 533 formed in the nipple 53 and the gas pressure introducing port 513 formed in the holder 51 communicating with the gas pressure introducing port 533. ing.

As described above, the inert gas such as N ₂ gas or Ar gas which has flowed into the optical fiber introducing portion 57 from the gas introducing port 531 enters the optical fiber introducing portion 57, and is introduced into the gas guide provided in the holder 51. It is discharged to the outside through the outlet 512. In addition, N ₂ introduced into the optical fiber introducing section 57
An inert gas such as gas or Ar gas is supplied by the differential pressure gauge 59 so that the inside of the optical fiber introducing portion 57 does not always have a negative pressure, so that air is prevented from entering the inside of the optical fiber introducing portion 57. You can Further, since an inert gas such as N ₂ gas or Ar gas is supplied to the inside of the optical fiber introducing portion 57 so that the inside of the optical fiber introducing portion 57 does not become a negative pressure, they are aligned in parallel and bundled in a band shape. When coating the resin 6 on the plurality of optical fiber strands 3, it is possible to block O ₂ gas from entering between the optical fiber strands 3 and between the optical fiber strands 3 and the coating resin 6.

On the upper side wall of the holder 51, there is provided a resin supply port 510 through which the resin 6 for coating the plurality of optical fiber strands 3 aligned in parallel by the nipple 53 and bundled into a band is introduced. Cage, this resin supply port 51
0 communicates with the resin coating chamber 56. Further, at the start of manufacturing the strip-shaped optical fiber core wire, the lower side wall of the holder 51 does not cover the resin containing air bubbles on the plurality of strip-shaped optical fiber element wires 3. Is provided with a resin overflow port 511 for discarding the resin charged in the initial stage.
Communicate with the resin coating chamber 56. This resin supply port 5
When the coating resin 6 is charged from 10, the resin coating chamber 56 is filled with the resin 6.

A plurality of optical fiber strands 3 aligned in parallel by the nipple 53 and bundled in a strip shape are located substantially at the center of the die 52 and pass through the resin coating chamber 56 filled with the resin 6. Is coated with resin and is drawn out from the flange side outlet of the die 52.

Reference numeral 7 is a resin curing furnace, for example, UV (ult
Raviole) furnace. The resin curing oven 7 in this embodiment is a UV oven because the resin that coats the optical fiber element wire 3 is a UV curing resin. When the UV curable resin 6 coated on the plurality of optical fiber strands 3 is cured in the resin curing furnace 7, a plurality of cores (for example,
(4 cores) optical fiber tape core wire 8 is manufactured.

Reference numeral 9 denotes a take-up device, which is used in the resin curing furnace 7
The optical fiber tape core wire 8 coated with the V-curable resin 6 is pulled and pulled with a predetermined tension. A winding device 10 winds the optical fiber tape core wire 8 drawn by the drawing device 9 onto a drum or the like.

In this way, in the coating head 5, a plurality of (for example, four, six, eight, etc.) optical fiber strands 3 are lined with the UV curable resin 6 as shown in FIG. To cover. After that, UV (ultrabio)
let) In a resin curing furnace 7 such as a furnace, a curable resin 6 coated on a plurality of optical fiber strands 3 is cured to form a plurality of optical fiber ribbons (4 cores, 6 cores, 8 cores, etc.). 8 is manufactured, taken up by the take-up device 9, and taken up by the take-up device 10.

Therefore, according to this embodiment, it is possible to prevent the curing reaction rate of the UV curing resin 6 from being reduced by O ₂ gas. Therefore, it is possible to make the inside curing rate and the outside curing rate of the coated UV curable resin the same, and to stably maintain the transmission characteristics, mechanical characteristics, and temperature characteristics of the optical fiber ribbon. . As a result, as shown in FIG. 3, the curing rate of the curable resin 6 can be kept the same even if the manufacturing speed of the tape core wire is increased, and even if the manufacturing speed of the optical fiber tape core wire is increased, it is not the same as the conventional product. It is possible to obtain a higher quality optical fiber ribbon.

[0033]

According to the present invention, a plurality of running optical fiber strands are juxtaposed and run in the fiber introducing portion of a nipple filled with an inert gas, and then UV is continuously applied in a resin coating chamber of a coating head. Since the resin is coated in a tape shape and UV-cured, the same curing rate is obtained both inside and outside the coated resin when a plurality of optical fiber wires are arranged in parallel while being continuously extruded for resin coating. As a result, an optical fiber tape core wire having stable transmission characteristics, mechanical characteristics, and temperature characteristics can be obtained without limiting the manufacturing speed of the optical fiber tape core wire.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram showing an embodiment of a method of manufacturing an optical fiber ribbon according to the present invention.

FIG. 2 is a cross-sectional view showing the coating head shown in FIG.

FIG. 3 is a graph showing the relationship between the curing rate of UV resin and the manufacturing speed of the optical fiber tape core wire manufactured based on the method of manufacturing the optical fiber tape core wire according to the present invention shown in FIG. FIG.

FIG. 4 is an overall configuration diagram showing a conventional method for manufacturing an optical fiber ribbon.

5 is a cross-sectional view showing the coating head shown in FIG.

FIG. 6 is a cross-sectional view of an optical fiber element wire on an optical fiber tape core wire manufactured by a conventional apparatus for manufacturing an optical fiber tape core wire.

[Explanation of symbols]

1 …………………………………………………… Optical fiber ribbon manufacturing equipment 2 ………………………………………… Supply equipment 3 …… ……………………………………………… Optical fiber strand 5 ……………………………………………… Coating head 51 …………………… …………………………… Holder 52 …………………………………………… Die 53 …………………………………………… Nipple 53… ……………………………………………… Gas inlet 57 ……………………………………………… Optical fiber inlet 59 …………………… ……………………… Differential pressure gauge 6 ……………………………………………… UV curable resin 7 ………………………………………… … Resin curing furnace 8 ……………………………………………… Optical fiber tape Line 9 ...................................................... take-up device 10 ................................................... take-up device

[Procedure amendment]

[Submission date] April 19, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] 0024

[Correction method] Change

[Correction content]

The nipple 53 is formed in a cylindrical shape and its tip is narrowed in a funnel shape. The opening shape of the tip is a substantially oval shape suitable for bundling a plurality of optical fiber element wires 3 in parallel. Is formed in. A flange 55 is provided at the rear end of the nipple 53,
The inside is hollow, and this cavity forms the optical fiber introducing portion 58 . This optical fiber introducing section 58
Is a place where a plurality of optical fiber strands 3 are guided and parallelized. Reference numeral 57 denotes a lid, which seals the optical fiber introducing portion 58 . That is, air does not enter the inside of the optical fiber introducing section 58 from the optical fiber introducing side. This prevents the inflow of air into the optical fiber introducing section 58 from the optical fiber introducing side.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0026

[Correction method] Change

[Correction content]

As described above, the inert gas such as N ₂ gas or Ar gas which has flowed into the optical fiber introducing portion 58 from the gas introducing port 531 enters the optical fiber introducing portion 58 and is introduced into the gas guide provided in the holder 51. It is discharged to the outside through the outlet 512. In addition, N ₂ introduced into the optical fiber introducing section 58
Since the gas or the inert gas such as Ar gas is supplied by the differential pressure gauge 59 so that the inside of the optical fiber introducing portion 58 does not always have a negative pressure, air is prevented from entering the inside of the optical fiber introducing portion 58 . You can Further, the optical fiber introducing section 58, since the inert gas such as N ₂ gas or Ar gas is supplied to the optical fiber introducing section 58 does not become negative pressure, bundled in a band shape aligned in parallel When coating the resin 6 on the plurality of optical fiber strands 3, it is possible to block O ₂ gas from entering between the optical fiber strands 3 and between the optical fiber strands 3 and the coating resin 6.

Claims (1)

[Claims] 1. A method of manufacturing an optical fiber ribbon, wherein a plurality of running optical fiber wires are arranged in parallel while being coated with a resin and cured to produce a plurality of running optical fiber wires which are inactive. A method for producing an optical fiber ribbon, comprising running a resin in a fiber-introduced portion filled with gas, continuously coating the resin, and UV-curing the fiber.