JP3127031B2 - Method and apparatus for manufacturing optical fiber ribbon - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for manufacturing an optical fiber ribbon, in which a plurality of optical fibers are covered with a coating material and formed into a tape. Prevents bubbles from entering the resin coating during the process, suppresses micro-strain of the optical fiber due to volume change of the bubble due to external temperature change, and reduces the optical transmission loss of the optical fiber. The present invention relates to a manufacturing method and a manufacturing apparatus.

[0002]

2. Description of the Related Art Conventionally, an optical fiber ribbon (hereinafter, abbreviated as a tape ribbon) in which a plurality of optical fiber wires are collectively covered in a tape shape has been used in the field of optical communication and the like, for example. It is used for optical fiber cables for the purpose of high density. The tape core is manufactured, for example, by the following manufacturing method.

FIG. 4 is a view showing a conventional apparatus for manufacturing an optical fiber ribbon, in which reference numeral 1 denotes a die spot, and 2 denotes a resin curing device (hereinafter abbreviated as a curing device). A die nipple port 1a, a die outlet 1b, and a resin supply port 1c are formed in the die spot 1, and inside the die spot 1, a resin supply device 3 connected to the resin supply port 1c is provided. A cured ultraviolet curable resin (hereinafter abbreviated as UV resin) 4 is filled. The curing device 2 is provided after the die spot 1 and has an ultraviolet irradiation lamp 2a disposed therein.

In order to manufacture a tape core using the above-described conventional optical fiber manufacturing apparatus, first, an optical fiber bundle 5 in which a plurality of optical fibers are arranged in parallel is inserted into a die spot 1 through a die nipple opening 1a. The outer periphery of the optical fiber bundle 5 is coated with an uncured UV resin in the die spot 1. Next, after the optical fiber ribbon 5a before curing is led out from the die exit 1b of the die spot 1, the tape ribbon 5a is introduced into the curing device 2, and the resin coating is irradiated with ultraviolet rays. The tape core 5b is cured and coated and cured.

[0005]

However, in the above-mentioned conventional method of manufacturing a ribbon fiber, the optical fiber bundle 5 is not used.
Is inserted into the die spot 1 through the die nipple port 1a, as shown in FIG.
In some cases, bubbles R may be mixed into the molten resin inside the die spot 1, which may cause the bubbles R to also be mixed into the coating resin Q of the tape core 5 b manufactured as shown in FIG. there were.

[0006] Such bubbles R in the coating resin undergo a volume change due to a temperature change. Therefore, the optical fiber covered with the UV resin having a large number of the bubbles R generates a strain under the influence of the stress caused by the volume change of the bubbles R, and further, the strain causes the optical transmission loss of the optical fiber. There was also a negative effect of the increase.

Conventionally, measures such as increasing the resin supply pressure to the die spot 1 have been taken in order to prevent the above-mentioned air bubbles from being mixed, but a sufficient effect has not been obtained in preventing the air bubbles from being mixed.

[0008] The present invention has been made in view of the above circumstances,
By preventing bubbles from being mixed into the coating resin during the manufacturing process of the tape core wire, it is possible to suppress the micro-strain of the optical fiber due to the volume change of the bubble due to the external temperature change, and to reduce the optical transmission loss of the optical fiber. It is an object of the present invention to provide a method and an apparatus for manufacturing a fiber ribbon.

[0009]

An object of the present invention is to provide an optical fiber bundle in which a plurality of optical fibers are arranged in parallel, which is fed into a die nipple of a die spot to which an uncured resin supply means is connected. The uncured resin is coated on the optical fiber bundle within the optical fiber bundle, and the optical fiber bundle coated with the uncured resin is led out from the die exit of the die spot. In a method of manufacturing an optical fiber ribbon coated collectively in the form of a tape, the problem is solved by feeding a bundle of optical fibers into the die spot from the die nipple port with a reduced pressure atmosphere near the die nipple port.

[0010] In the above-described method of manufacturing a tape core according to the present invention, an uncured resin is housed therein, and an optical fiber bundle in which a plurality of optical fibers are arranged in parallel is fed from a die nipple port. In an apparatus for manufacturing an optical fiber ribbon, the optical fiber bundle is coated with an uncured resin and led out from a die outlet, and an uncured resin curing unit provided at a stage subsequent to the die spot. It is preferable to use the manufacturing apparatus according to claim 2 having a structure in which a pressure reducing means for reducing the pressure in the vicinity of the die nipple port is provided on the die nipple port side of the die spot.

[0011]

According to the method of manufacturing a tape core wire of the present invention, as described above, the optical fiber bundle is fed into the die spot from the die nipple port with the reduced pressure atmosphere near the die nipple port. Bubbles are prevented from entering the resin in the die spot from the die nipple opening, thereby obtaining a tape core wire having a coating resin with few mixed bubbles.

FIG. 1 is a view showing an example of an apparatus for manufacturing a tape core wire according to the present invention.
2 is a decompression chamber, 13 is a curing device, and 14 is an optical fiber transfer device (hereinafter abbreviated as a transfer device).

As shown in FIG. 2, a die nipple port 11a, a die outlet 11b, and a resin supply port 11c are formed in the die spot 11, and the die spot 11 communicates with the resin supply port 11c. Resin supply device 1
5 is filled with the uncured UV resin 16.

A decompression chamber 12 is provided outside the die nipple port 11a of the die spot 11. Suction ports 12a, 12a and a fiber bundle feeding port 12b are formed in the decompression chamber 12, and suction pumps 17, 17 are respectively attached to the suction ports 12a, 12a.

As shown in FIG. 1, the curing device 13 is provided after the die spot 11 and has an ultraviolet irradiation lamp 18 therein.

The transfer device 14 transfers the optical fiber bundle in which a plurality of optical fibers are arranged in parallel to the decompression chamber 12 → the die spot 1
This is a device for sequentially feeding each device in the order of 1 → hardening device 13.

In order to carry out the method for manufacturing a tape core according to the present invention using the apparatus for manufacturing a tape core of the present embodiment, first, the die spot 11 of the tape core manufacturing apparatus is used.
The air in the decompression chamber 12 provided on the outer side of the die nipple port 11a is suctioned by the suction pumps 17 and decompressed, and the atmosphere in the decompression chamber 12 is made lower than the normal pressure.

Next, the optical fiber bundle 20 in which a plurality of optical fibers are arranged in parallel is transported by the transfer device 14 to the decompression chamber 1.
2 (in a depressurized state) from the fiber bundle inlet 12b,
Further, it is fed into the die spot 11 from the decompression chamber 12 through the die nipple port 11a, and the die spot 1
In step 1, the optical fiber bundle 20 is coated with an uncured UV resin.

Next, the optical fiber bundle 20 coated with uncured UV resin is coated on the optical fiber bundle 20 from the die outlet 11b of the die spot 11 by using the transfer device 14.
Then, the uncured optical fiber bundle 20a is introduced into the curing device 13.

The optical fiber bundle 20a introduced into the curing device 13 is irradiated with ultraviolet rays by an ultraviolet irradiation lamp 18 provided in the curing device 13, whereby the uncured UV resin is cured. Thus, an optical fiber ribbon 20b having a cured UV coating is obtained.

In the apparatus for manufacturing a tape core of the present embodiment,
As described above, since the decompression chamber 12 is provided outside the die nipple port 11a of the die spot 11,
At the time of tape core production, by using the suction pumps 17 and 17 to lower the atmosphere in the decompression chamber 12 below normal pressure,
When the optical fiber bundle is fed from the die nipple opening 11a of the die spot 11, air bubbles are prevented from being mixed into the resin.
Therefore, in a tape core manufactured using this tape core manufacturing apparatus, the number of bubbles present in the coating resin is extremely small, thereby causing a change in the volume of the bubbles in the coating resin. The stress generated in the coating resin can be suppressed, and the optical transmission loss of the optical fiber caused by the stress can be reduced.

[0022]

【Example】

(Example 1) Using a tape core manufacturing apparatus having the same configuration as that of the above-described example, the coating thickness (N) shown in FIG.
Was actually manufactured.

First, the air in the decompression chamber 12 of the tape core manufacturing apparatus was sucked by the suction pumps 17, 17, and the pressure inside the decompression chamber 12 was reduced to 0.9 atm or less.

Next, the UV resin is applied to the bare optical fiber 21 for 2 hours.
Eight optical fibers 18 having an outer diameter (R) of 260 μm were prepared by coating a colored ink layer on an optical fiber having a layer outer diameter of 250 μm. Further, these eight optical fibers 18 are arranged in parallel to form an optical fiber bundle 20,
The optical fiber bundle 20 was fed into the decompression chamber 12 by the transfer device 14 (via the fiber bundle feed port 12b).
The decompression chamber 12 used had a fiber bundle inlet 12b having a dimension of 0.4 mm × 2.2 mm.

Next, the optical fiber bundle 20 sent into the decompression chamber 12 is sent into the die spot 11 through the die nipple port 11a. UV resin was coated.
In this case, as the die spot 11, a die spot having a size of the die nipple opening 11a of 0.4 mm × 2.2 mm and a size of the die exit b of 0.36 mm × 2.2 mm is used. Inside, the uncured UV resin 16 was supplied via the resin supply port 11c. However, the resin supply pressure at this time is 1 kg / cm ² using the resin supply device 15.
Was adjusted.

Next, using the transfer device 14, the optical fiber bundle 20a obtained by coating the uncured UV resin on the optical fiber bundle 20 is transferred to the die exit 11b of the die spot 11.
And the optical fiber bundle 20a was immediately fed into the curing device 13.

Finally, ultraviolet rays were irradiated to the optical fiber bundle 20a in the curing device 13, whereby the uncured UV resin was cured to produce a tape core 20b (Example 1).

(Example 2) Example 2 was the same as Example 1 except that the apparatus for manufacturing a tape core having the same configuration as Example 1 was used, and the resin supply pressure into the die spot was 3 kg / cm ^2. The tape core manufacturing apparatus was operated under the same operating conditions to produce a tape core 20b (Example 2).

(Embodiment 3) A tape core manufacturing apparatus having the same configuration as that of Embodiment 1 described above was used except that the size of the fiber bundle inlet 12b of the decompression chamber 12 was set to 0.3 mm x 2.2 mm. The tape core 20b (Example 3) was actually manufactured under the same operating conditions as in Example 1 described above.

(Embodiment 4) A tape core manufacturing apparatus having the same configuration as that of Embodiment 1 described above was used except that the size of the fiber bundle inlet 12b of the decompression chamber 12 was 0.5 mm x 2.2 mm. The tape core 20b (Example 4) was actually produced under the same operating conditions as in Example 1 above.

(Embodiment 5) The size of the die nipple port 11a of the die spot 11 is 0.3 mm × 2.2 mm, the size of the die outlet 11b is 0.27 mm × 2.2 mm,
The size of the fiber bundle inlet 12b is 0.3 mm x 2.2 mm.
3 except that the coating thickness (N) shown in FIG. 3 was 5 μm and the tape thickness (M) was used under the same operating conditions as in Example 1 above, using a tape core manufacturing apparatus having the same configuration as in Example 1 described above. )
Was actually manufactured with a tape core 20b (Example 5) having a width of 270 μm and a tape width (W) of 2.15 mm.

Example 6 Example 5 was the same as Example 5 except that a tape core manufacturing apparatus having the same configuration as Example 5 was used and the resin supply pressure into the die spot was 3 kg / cm ^2. The tape core manufacturing apparatus was operated under the same operating conditions to produce a tape core 20b (Example 6).

(Comparative Example 1) A tape core manufacturing apparatus having the same configuration as the above-described conventional tape core manufacturing apparatus shown in FIG. 4 was used, and the coating thickness (N) shown in FIG. Tape thickness (M) is 360 μm and tape width (W) is 2.15
The tape core 5b of mm was actually produced.

First, an optical fiber bundle 5 in which eight optical fibers 6 are arranged in parallel is set so that the size of the die nipple port 1a is equal to 0.
4mm x 2.2mm, die exit b dimension is 0.36mm x
The die nipple opening 1 of the die spot 1 which is 2.2 mm
a into the die spot 1, and the outer periphery of the optical fiber bundle 6 was coated with an uncured UV resin in the die spot 1.

Next, an optical fiber bundle 5 coated with uncured UV resin is passed through the die exit 1b of the die spot 1.
a, the optical fiber bundle 5a is fed into the curing device 2, and the uncured UV resin is irradiated with ultraviolet light.
A tape core wire 5b obtained by curing a V resin was produced.

(Comparative Example 2) The same procedure as in Comparative Example 1 was carried out except that a tape core manufacturing apparatus having the same configuration as that of Comparative Example 1 was used, and the resin supply pressure into the die spot was 3 kg / cm ^2. The tape core manufacturing apparatus was operated under the same operating conditions to produce a tape core 5b (Comparative Example 2).

(Comparative Example 3) A tape core manufacturing apparatus having the same configuration as that of Comparative Example 1 described above except that the size of the die outlet 1b of the die spot 1 was set to 0.27 mm × 2.2 mm was used. Under the same operating conditions as in Example 1, a tape core 5b (Comparative Example 3) having a coating thickness (N) of 5 μm, a tape thickness (M) of 270 μm, and a tape width (W) of 2.15 mm shown in FIG. Actually produced.

(Comparative Example 4) The same procedure as in Comparative Example 3 was carried out, except that the apparatus for manufacturing a tape core having the same configuration as in Comparative Example 3 was used, and the resin supply pressure into the die spot was 3 kg / cm ^2. The tape core manufacturing apparatus was operated under the same operating conditions to produce a tape core 5b (Comparative Example 4).

(Experimental Examples) The following tests and tests shown below were performed on each of the tape cores produced in Examples 1 to 6 and Comparative Examples 1 to 4. First, eight optical fibers (length: 500 m) before being taped were completely wound around resin bobbins each having a diameter of 320 mm, and each of the eight optical fibers in this state had an optical transmission loss at a wavelength of 1.55 μm. Was measured.
Next, the measured optical transmission loss values of each optical fiber are summed up,
The sum value obtained by dividing by 8 to obtain a light transmission loss average value x ₁ taped before the optical fiber. Next, the optical fiber subjected to the above measurement was converted into a tape core wire, and the tape core wire 500 m was completely wound around a resin bobbin having a diameter of 320 mm in the same manner as described above. About the optical transmission loss under the same conditions as above,
To obtain a light transmission loss mean value x ₂ after taping. The difference (x ₂ −x) between the average value x ₁ of the optical transmission loss of the optical fiber before the tape and the average value x ₂ of the optical transmission loss of the optical fiber after the tape.
₁ ) was calculated, and the calculated value was defined as an optical transmission loss increment (Δx) before and after tape formation.

The tape core wire used for the above measurement was φ300
The optical transmission loss at a wavelength of 1.55 μm was measured for each optical fiber in the tape core wire in this state. Then sum the optical transmission loss value of the optical fibers was measured, and divided by the sum value obtained 8 to obtain an optical transmission loss average value y ₁ of the optical fiber. The difference (y ₁ −x ₁ ) between the average value of the optical transmission loss y ₁ and the average value of the optical transmission loss x ₁ is calculated, and the calculated value is calculated as the light when the tape is wound in a bundle. Transmission loss increment (Δy ₁ ).

The bundle of tapes wound in a bundle was subjected to the above test in a thermostat having an internal temperature of -40.degree. C., and after 24 hours, the ribbon was taken out and the tape was immediately taken out. The optical transmission loss at a wavelength of 1.55 μm was measured for each optical fiber in the core. Next, the measured optical transmission loss values of the respective optical fibers were totaled, and the obtained total value was divided by 8 to obtain an average optical transmission loss value y ₂ of the optical fibers in a low temperature state. The difference (y ₂ −y ₁ ) between the average value of the optical transmission loss y ₁ obtained in the above test and the average value of the optical transmission loss y ₂ in the low-temperature state is calculated. Optical transmission loss increment (Δ
y ₂ ).

The bundle of tapes wound in a bundle and subjected to the above test was placed in a constant temperature bath, and the temperature inside the constant temperature bath was raised from room temperature to 60 ° C. and further from 60 ° C. for 4 hours. The temperature was changed to -40 ° C (1 cycle). After repeating this operation for 5 cycles, a wavelength of 1.55 was obtained for each optical fiber in the ribbon at −40 ° C.
The optical transmission loss at μm was measured. Next, the measured optical transmission loss values of the respective optical fibers are summed up, and the obtained summed value is calculated as 8
To obtain an average optical transmission loss y ₃ after the heat cycle test of the optical fiber. An optical transmission loss value y ₁ obtained in tests of the difference between the light transmission loss average value y ₃ after the heat cycle test (y ₃ -y ₁₎ is calculated, the calculated value into ribbons It was defined as an optical transmission loss increment (Δy ₃ ) when a heat cycle test was performed.

Each of the prepared tape cores (length: 500 m)
The number of bubbles in the resin coating is measured by a microscope (magnification: 100 times) within a range of 50 mm each in the longitudinal direction of the tape core wire for each 100 m of each tape core wire. Calculated for each tape core. the above~
Table 1 shows the test results and the test results.

[0044]

[Table 1]

[0045]

As described above, in the method of manufacturing a tape core wire according to the present invention, when the optical fiber bundle is fed into the die nipple opening of a die spot having an uncured resin therein, Since the pressure in the vicinity of the nipple port is lower than the normal pressure, it is possible to prevent bubbles from entering the resin in the die spot from the die nipple port. Therefore, the number of bubbles existing in the coating resin of the tape core wire manufactured by the method of manufacturing the tape core wire is extremely small,
Thereby, the strain stress caused by the bubbles in the coating resin is suppressed. In addition, based on the effect of suppressing the strain stress,
Optical transmission loss of an optical fiber in a cold environment is reduced.

[Brief description of the drawings]

FIG. 1 is a schematic view showing an example of an apparatus for manufacturing a tape core wire according to the present invention.

FIG. 2 is an enlarged sectional view of a die spot indicated by reference numeral 11 in FIG.

FIG. 3 is a cross-sectional view of a tape core manufactured by a method for manufacturing a tape core according to the present invention or a conventional method for manufacturing an optical fiber tape core.

FIG. 4 is a schematic view illustrating an example of a conventional apparatus for manufacturing a tape core.

FIG. 5 is an enlarged cross-sectional view of a die spot indicated by reference numeral 1 in FIG.

FIG. 6 is a cross-sectional view of a tape core indicated by reference numeral 5b in FIG.

[Explanation of symbols]

11: die spot, 11a: die nipple opening, 11
b: die outlet, 12: decompression chamber, 13: resin curing device (curing device), 16: ultraviolet curing resin (UV resin), 1
7 suction pump, 20 optical fiber bundle, 20a optical fiber bundle (uncured), 20b optical fiber ribbon

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Naoki Okada 1440 Mutsuzaki, Sakura City, Chiba Prefecture Fujikura Electric Wire & Cable Co., Ltd. Sakura Plant 208814 (JP, A) Hikaru Hei 2-87038 (JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) G02B 6/44

Claims (2)

(57) [Claims] An optical fiber bundle in which a plurality of optical fibers are arranged in parallel is fed to a die nipple opening of a die spot to which an uncured resin supply means is connected, and the optical fiber bundle is unloaded within the die spot. An optical fiber that coats a cured resin and derives an optical fiber bundle coated with the uncured resin from a die outlet of the die spot, and then performs a curing process on the uncured resin to collectively cover the optical fiber bundle in a tape shape. A method for producing an optical fiber ribbon, comprising: feeding a bundle of optical fibers into the die spot from the die nipple opening under a reduced pressure atmosphere near the die nipple opening. 2. An uncured resin is housed inside, and an optical fiber bundle in which a plurality of optical fibers are arranged in parallel is fed from a die nipple port, the optical fiber bundle is coated with the uncured resin, and is derived from a die outlet. An optical fiber ribbon manufacturing apparatus comprising: a die spot to be formed; and a curing means for uncured resin provided at a stage subsequent to the die spot. An apparatus for manufacturing an optical fiber ribbon, wherein a pressure reducing means for setting an atmosphere is provided.