JP2585373Y2 - Resin coating device for optical fiber or aggregate thereof - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in an apparatus for coating an optical fiber or an assembly thereof with a resin, for example.

[0002]

2. Description of the Related Art A resin coating apparatus of this type comprises a resin supply tank and a resin coating die for receiving a resin from the resin supply tank and coating the resin on an optical fiber or an assembly thereof. The resin stored in the resin supply tank is pressurized and supplied to the resin coating die with an inert gas such as nitrogen gas supplied by pressurizing the resin supply tank, and the optical fiber or an aggregate thereof (hereinafter referred to as an optical fiber or the like) In other words, the resin is coated when passing through the resin application die, and then the resin is cured through the resin curing means.
The resin is poured from the resin container into the resin supply tank and stored. The resin curing means comprises an ultraviolet irradiation means when the resin is an ultraviolet curable resin, and comprises a heating means when the resin is a thermosetting resin.

[0003]

In a resin coating apparatus of this kind, when the resin is poured from the resin container into the resin supply tank, it is avoided that air enters the resin and generates many bubbles in the resin. Absent. These bubbles are pumped together with the resin to the resin application die, and thus have bubbles in the coating of the optical fiber or the like. If the foam in the resin is large, as shown in FIG. 5, the outer peripheral surface of the coating 2 of the optical fiber or the like 1 partially swells to form irregularities 2a, or the foam when heated in the resin curing means. However, there is a defect that the appearance of the coating 2 is deteriorated due to rupture and formation of a hole 2b in the coating. In addition, even when the foam is of a medium size that does not deteriorate the appearance of the coating, if the optical fiber or the like is used in a low-temperature atmosphere, the shrinkage of the coating causes the optical fiber or the like to bend at a portion having the bubble and transmission loss to occur. There was a disadvantage of becoming larger.

Further, when the lid of the resin container is opened, or when a suction pipe is inserted into the resin container to supply the resin to the resin supply tank, foreign matters may be mixed into the resin. At the time of coating, the temperature is kept at about 30 ° C. to 80 ° C. At this time, a part of the resin may gel. As shown in FIG. 6, when these foreign substances 5 or gel components 6 are present in the coating of the optical fiber 1, the optical fiber 1
Transmission characteristics and mechanical characteristics may be significantly reduced.

In the prior art, bubbles are generated in the resin.
Air bubbles at the inlet of the resin supply tank to prevent
A tank for removing foreign substances mixed in the resin.
Filter between the bubble removal tank and the resin supply tank.
It has been proposed to install
87038). However, bubble elimination tank and fill
Installation of equipment will increase equipment costs and supply resin.
No filter between tank and resin application base
Therefore, remove the gel generated in the resin supply tank.
There was a drawback that could not be done.

One object of the present invention is to avoid the above disadvantages.
And enters the resin without installing a bubble elimination tank
Foams can impair the appearance of the coating and reduce transmission properties
Coating optical fiber etc. with resin to prevent
Optical fiber or resin coating device for aggregate thereof
Is to provide. It is another object of the present invention is, tree
Effectively prevent foreign matter and gel from entering the fat
An optical fiber or a resin coating apparatus for assembling the optical fiber so that the resin can be coated on the optical fiber or the like without deteriorating the transmission characteristics and mechanical characteristics of the optical fiber or the like by these foreign matters and gel components. Is to provide.

[0007]

According to the present invention, as a means for solving one of the above-mentioned problems, a resin supply tank and a resin supplied from the resin supply tank are supplied and the resin is supplied to an optical fiber or an aggregate thereof. An optical fiber comprising a resin coating die to be coated or a resin coating device for an aggregate thereof, wherein a filter having a resin passage hole having a diameter of 100 μm or less is provided between the resin supply tank and the resin coating die. An object of the present invention is to provide a resin coating device for an optical fiber or an assembly thereof.

According to the present invention, as another means for solving the above-mentioned problems, a resin supply tank and a resin coating for receiving a supply of resin from the resin supply tank and coating the resin on an optical fiber or an aggregate thereof are provided. An optical fiber comprising a base or a resin coating apparatus for an aggregate thereof, wherein a filter having a diameter of a resin passage hole of 2 μm or less is provided between the resin supply tank and the resin coating base immediately before the resin coating base. An optical fiber or a resin coating device for an aggregate thereof is provided.

[0009]

As described above, when a filter having a resin passage hole having a diameter of 100 μm or less is provided between the resin supply tank and the resin application mouthpiece, bubbles that have entered the resin are subdivided by the filter. When the optical fiber is used in a low-temperature atmosphere, the optical fiber or the aggregate thereof does not bend, and the transmission characteristics are not deteriorated.
Therefore, it is not necessary to install a bubble removal tank,
A high-quality optical fiber or an aggregate thereof can be obtained.

A filter is provided immediately before the resin application die.
When the resin passage hole of this filter is set to 2 μm or less, foreign matter and gel components in the resin can be removed in addition to the fragmentation of the foam as described above. Transmission characteristics and mechanical characteristics are not deteriorated. If the filter is separated from the resin application die, the gel component is generated again after the resin has passed through the filter. Therefore, the filter needs to be located immediately before the resin application die.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the drawings, an embodiment of the present invention will be described in detail. FIG. 1 shows a resin coating apparatus 10 for an optical fiber or an assembly thereof according to the present invention. It comprises a tank 12 and a resin coating base 14 which receives the supply of the resin 3 from the resin supply tank 12 and coats the resin 3 on the optical fiber or its aggregate (optical fiber or the like) 1. As shown in FIG. 2, the resin 3 is poured from a resin container 16 into a resin supply tank 12, and is pressure-fed from the resin supply tank 12 to the resin coating die 14 by an inert gas such as nitrogen gas. Also, the resin coating base 14
The coating 2 formed by applying the resin 3 is cured by a resin curing means 18 disposed downstream thereof.

The resin coating apparatus 10 of the present invention is provided with a filter 20 having a resin passage hole having a diameter of 100 μm or less, preferably 2 μm or less, between the resin supply tank 12 and the resin coating base 14. The diameter of the resin passage hole is 2 μm (50
%) Or less, the filter 20 is provided immediately before the resin coating base 14 so that the resin 3 does not gel again after passing through the filter 20.

As described above, when the resin 3 is transferred from the resin container 16 into the resin supply tank 12, air enters into the resin 3 to form a large number of bubbles 4. The filter is subdivided by a filter 20 having a diameter of 100 μm or less provided between the resin supply tank 12 and the resin application base 14. For this reason, the coating 2 is hardly partially expanded by the bubbles 4 or a hole is formed by the rupture of the coating 2, and the appearance of the coating can be improved. In addition, when the optical fiber 1 is used in a low-temperature atmosphere, bending of the optical fiber 1 is prevented, and the transmission characteristics are hardly reduced.

Further, when the lid of the resin supply tank 12 is opened or the like, foreign matter 5 is mixed into the resin 3 or the resin 3 is kept warm and a part of the resin 3 is gelled to form a gel portion 6. In some cases, these foreign substances 5 and gel components 6 are removed by a filter 20 having a diameter of 2 μm or less.
Therefore, the transmission characteristics and mechanical characteristics of the optical fiber 1 and the like do not deteriorate.

The diameter of the resin passage hole of the filter 20 is set to 100
μm or less because the resin passage hole of the filter is 100μ
This is because it has been experimentally confirmed that when it is larger than m, the foam is insufficiently fragmented, resulting in poor appearance and reduced transmission characteristics at low temperatures. In some experimental examples in which the optical fiber was coated with resin with or without various filters having different diameters of the resin passage holes, the appearance was poor when the resin was coated with no filter, but the resin was not. The diameter of the passage hole is 50
When the resin was coated with the filters of 0 μm and 100 μm, it was confirmed that the appearance was good in each case. Therefore, when only the appearance of the coating is considered, it is understood that a filter having a resin passage hole of 500 μm or less may be used.

On the other hand, FIG. 3 shows the results of measuring the temperature-optical transmission loss characteristics of the optical fiber having the coating obtained in the above experimental example. In FIG. 3, line a shows the characteristics of the optical fiber coated with resin without using a filter, and line b shows the characteristics of the optical fiber coated with resin using a filter having a resin passage hole diameter of 500 μm. Line c shows the characteristics of the optical fiber coated with resin using a filter having a resin passage hole diameter of 100 μm. As can be seen from FIG. 3, when the resin was coated using a filter having a diameter of the resin passage hole of 100 μm, no increase in light transmission loss was observed even in a low temperature atmosphere of −30 ° C. Therefore, when considering both the appearance of the coating and the transmission characteristics, it is understood that the diameter of the resin through-hole of the filter is required to be 100 μm or less.

It is preferable that the diameter of the resin passage hole of the filter 20 be 2 μm or less. If the resin passage hole of the filter is larger than 2 μm, the foreign matter 5 in the resin 3 and the gel component 6
Cannot be removed. That is, using a filter in which the diameter of the resin passage hole is 1 μm to 30 μm, and using a double die, a resin obtained by mixing aluminum particles that have passed through a 100 μm mesh into an optical fiber strand having a preform variation of 0.35%. Is coated over 30 km,
A primary coating having an outer diameter of 0.18 mm and a secondary coating having an outer diameter of 0.24 mm were formed. Thereafter, the optical fiber obtained in each of the experimental examples was subjected to 1% screening to measure the breakage rate in each of the experimental examples, and the 2 km of the optical fiber obtained in each of the experimental examples was made of stainless steel having a body diameter of 300 mm. FIG. 4 shows the results of measuring the loss difference from the laser light source at 1.57 μm five times by winding the bobbin at a tension of 10 g and 70 g. In FIG. 4, line d is 1 μm
The transition of the screening rupture rate for each filter of ３０30 μm is shown, and the line e shows the loss difference. As can be seen from FIG. 4, when a filter having a resin passage hole diameter of 2 μm or less is used, both the breaking rate and the loss difference depend on the particle diameter in the resin,
It has been significantly reduced. Therefore, the resin passage hole of the filter is required to be 2 μm or less. The loss difference refers to a difference between a loss value at 70 g and a loss value at 10 g.

Further, with or without the use of a filter having a resin passage hole having a diameter of 2 μm, the optical fiber has a 2 m / sec.
At a linear velocity of c, the urethane acrylic UV curable resin
In two experimental examples in which an optical fiber wire having an outer diameter of 400 μm was formed by coating over 000 km, the protrusions (knobs) of these wires were measured by a protrusion detection device, and the resin was coated without using a filter. In this case, 48 protrusions were found, but when the resin was covered with a filter having a resin passage hole having a diameter of 2 μm, only 13 protrusions were found. That is, by using a filter having a size of 2 μm or less, the defective portion of the external appearance could be reduced to about ４.

[0019]

According to the present invention, as described above, the bubbles in the resin are subdivided and the optical fiber or the like is coated with the resin.
It does not degrade the appearance of the coating and does not degrade the transmission characteristics and mechanical characteristics of the optical fiber.In addition, it removes foreign substances and gel components in the resin, so that the transmission characteristics and the mechanical characteristics of the optical fiber are degraded. Therefore, there is a practical advantage that a resin such as an optical fiber can be coated well. In particular, according to the present invention,
No need to actively remove bubbles from the resin, thus eliminating bubbles
Equipment costs can be reduced because no tank is installed
Yes, and a filter for removing foreign matter is located just before the resin application base.
Resin before the gel regrows.
Obtain good quality optical fiber or its aggregate because it is overturned
be able to.

[Brief description of the drawings]

FIG. 1 is a schematic system diagram of a resin coating device according to the present invention.

FIG. 2 is an explanatory view of a state in which a resin is poured into a resin supply tank of the resin coating device of the present invention.

FIG. 3 is a graph showing the temperature-optical loss characteristics of various optical fibers having a resin coating formed by the device of the present invention and another device.

FIG. 4 is a graph showing the breakage rate and loss difference of various optical fibers having a resin coating formed by the device of the present invention and another device.

FIG. 5 is a cross-sectional view of a coating of an optical fiber formed by applying a resin while having a bubble according to a conventional technique.

FIG. 6 is a cross-sectional view of an optical fiber coating formed by applying a resin with a foreign substance or a gel mixed therein according to a conventional technique.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Optical fiber etc. 2 Coating 3 Resin 4 Bubble 5 Foreign material 6 Gel content 10 Resin coating device 12 Resin supply tank 14 Resin coating base 20 Filter

Claims (2)

(57) [Scope of request for utility model registration] An optical fiber or a resin coating apparatus for an aggregate thereof, comprising: a resin supply tank and a resin application base for receiving a resin from the resin supply tank and coating the resin on an optical fiber or an aggregate thereof. The diameter of the resin passage hole is 100 μm between the resin supply tank and the resin application die.
An optical fiber or a resin coating apparatus for an aggregate thereof, comprising: a filter of m or less. 2. An optical fiber or resin assembly apparatus comprising a resin supply tank and a resin coating die for receiving resin from the resin supply tank and coating the resin on an optical fiber or an assembly thereof. An optical fiber or a resin coating apparatus for assembling the optical fiber, comprising a filter having a resin passage hole diameter of 2 μm or less between the resin supply tank and the resin coating die immediately before the resin coating die.