JP2004177676A - Optical fiber washing device and washing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical fiber washing device and washing method of simple configuration to eliminate the need for adjusting the holding position of an optical fiber in spite of a fluctuation in liquid level of a washing liquid and to prevent a fiber coating from being wet with the washing liquid even when used on a ship or the like which pitches and rolls. <P>SOLUTION: The optical fiber washing device in which the coating removing portion at the end of the glass-fiber cord or multiple optical fiber is immersed into the washing liquid to wash the fiber by ultrasonic vibrations is equipped with a float 25 to be floated within the washing liquid 23 in a washing tub 22 and a holding section 26 for immersing the coating removing portion 20 of the optical fiber 20 into the washing liquid and holding the same at the float 25. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an optical fiber cleaning apparatus and a cleaning method for immersing a coating removal portion at an end of an optical fiber in a cleaning liquid and cleaning the same by ultrasonic vibration.
[0002]
[Prior art]
When the optical fibers are fusion-spliced, the coating at the end of the optical fiber is removed to expose the bare glass fiber, cut to a predetermined length from the coated end, and then both cut end faces of the optical fiber are cut. And heat-sealed. After the coating of the optical fiber is removed, the bare fiber surface is usually cleaned or washed to remove debris from the coating removal on the bare fiber surface, dust and fine particles attached during operation. If the cleaning is insufficient, positioning at the time of fusion splicing may not be performed correctly, or dust or the like may enter the fusion spliced portion. As a result, the connection loss of the connection portion increases or the connection strength decreases.
[0003]
As a method of cleaning the coating removal portion of the optical fiber end without touching other solids, there is known a method of immersing the coating removal portion of the optical fiber end in a cleaning liquid and cleaning by ultrasonic vibration (for example, Patent Document 1). FIG. 5 is a diagram schematically illustrating the optical fiber cleaning device disclosed in Patent Document 1. In the drawing, 1 is a cleaning tank, 2 is a support substrate, 3 is a base ring, 4 is a holder ring, 5 is a central element, 6 is a through hole, 7 is a projection, 8 is a light guide, 9 is an adjustment ring, and 10 is a lock. A nut, 11 is a cleaning liquid, 12 is a fiber holder, 12a is a holder base, 12b is a holding lid, 13 is an optical fiber (ribbon fiber), 13a is a bare fiber, and 13b is a fiber coating.
[0004]
The cleaning tank 1 is formed of a cylindrical container, and is attached to the support substrate 2 of the cleaning device with the upper flange portion 1a interposed between the base ring 3 and the holder ring 4. A central element 5 is slidably arranged in the holder ring 4 and an adjusting ring 9 is rotatably mounted on the upper end of the central element 5. The adjustment ring 9 is screwed to the holder ring 4 and slides the central element 5 in the vertical direction by rotating. Further, a lock nut 10 is screwed into the holder ring 4, and the rotational movement of the adjustment ring 9 is locked by bringing the lock nut 10 into contact with the lower end of the adjustment ring 9.
[0005]
In the center of the central element 5, a through hole 6 whose upper side is widened is provided, and a projection 7 is provided below the through hole 6. Also mounted on the central element 5 is a glass or plastic light guide 8. The adjustment ring 9 is rotated while the cleaning liquid 11 is contained in the cleaning tank 1, and the vertical position of the central element 5 is adjusted. When the lower end 8a of the light guide 8 comes into contact with the cleaning liquid 11, the upper surface of the light guide 8 becomes dark, and the rotation of the adjustment ring 9 is stopped at this position. Next, the lock nut 10 is rotated until it comes into contact with the lower end of the adjustment ring 9 to lock the adjustment position.
[0006]
The end of the optical fiber 13 to be cleaned is held by the fiber holder 12. The fiber holder 12 has a shape in which a pair of holding lids 12b are provided on a holder base 12a so as to be openable and closable, and the optical fiber 13 is fixed by closing the holding lid 12b. The distal end of the optical fiber 13 is held by the fiber holder 12 in such a manner that the bare fiber 13a having a predetermined length is exposed by removing the fiber coating 13b, and is inserted into the through hole 6 of the central element 5 in this state.
[0007]
The lower end of the fiber holder 12 hits the projection 7 provided below the through-hole 6 to stop the insertion, and the bare fiber 13a exposed from the end of the fiber coating 13b can be immersed in the cleaning liquid 11 to a predetermined position. The cleaning tank 1 is provided with a piezoelectric vibrating means (not shown) for applying ultrasonic vibration, and the cleaning liquid 11 is vibrated to be cleaned for a predetermined time. After the washing, the bare fiber 13a having a predetermined length is cut from the end of the fiber coating 13b so as to be exposed, and then fusion-spliced.
[0008]
[Patent Document 1]
Japanese Patent Application Laid-Open No. 2000-180636
[Problems to be solved by the invention]
By using the above-described cleaning apparatus and keeping the level of the cleaning liquid 11 at rest, the cleaning can be performed without the cleaning liquid 11 coming into contact with the fiber coating 13b. However, for example, in a case where connection work is performed in a ship on the sea at the time of laying or maintaining a submarine optical cable, the washing device itself is shaken by the shake of the ship. In this case, the liquid level of the cleaning liquid 11 fluctuates up and down, and a wave is easily generated on the liquid surface.
[0010]
Acetone is often used as the cleaning solution for the end of the optical fiber, and the fiber coating 13b easily swells when wet with acetone or the like. In particular, when an optical fiber is to be fusion spliced with high strength, positioning and the like are performed by clamping the end portion of the fiber coating 13b. If the fiber coating 13b swells, accurate positioning cannot be performed. In addition, since the cleaning liquid has flammability, there is a problem that the fiber coating 13b is easily burned by heat at the time of fusion. Therefore, it is necessary to clean the fiber coating 13b so that the cleaning liquid 11 does not adhere to the fiber coating 13b.
[0011]
However, the optical fiber cleaning apparatus shown in FIG. 5 is difficult to adjust to sudden fluctuations in the liquid level, and is not suitable for use on a swaying ship or the like. Although the cleaning liquid 11 changes due to consumption and evaporation, the liquid level is constantly monitored, and the cleaning liquid 11 is replenished or the adjusting ring 9 is rotated so as to keep the liquid level constant. It is necessary to adjust the position, and the workability is not good. Note that a method of automatically adjusting the liquid level by detecting the liquid level with a sensor is conceivable, but the apparatus is complicated and large, so that the cost is high.
[0012]
The present invention has been made in view of the above circumstances, even if the liquid level of the cleaning liquid fluctuates, does not require adjustment of the holding position of the optical fiber, even when used on a swaying ship or the like, An object of the present invention is to provide an optical fiber cleaning apparatus and a cleaning method having a simple configuration in which a fiber coating is not wetted by a cleaning liquid.
[0013]
[Means for Solving the Problems]
An optical fiber cleaning apparatus according to the present invention is an optical fiber cleaning apparatus that cleans a coating removal portion of a single-core or multi-core optical fiber end by immersing it in a cleaning liquid and ultrasonically vibrating the cleaning liquid in the cleaning tank. A float is provided, and a holding section is provided on the float to hold a portion where the coating of the optical fiber is removed by immersing the portion in a cleaning liquid.
[0014]
Further, the optical fiber cleaning method according to the present invention is an optical fiber cleaning method in which a coating removal portion of a single-core or multi-core optical fiber end portion is immersed in a cleaning liquid and cleaned by ultrasonic vibration, and The float is floated on the cleaning liquid, the end of the optical fiber is held on the float, and the coating removed portion of the end of the optical fiber is immersed in the cleaning liquid.
[0015]
BEST MODE FOR CARRYING OUT THE INVENTION
The optical fiber to be cleaned according to the present invention is a single-core or multi-core optical fiber to be fusion spliced. The single-core optical fiber is obtained by coating the outer surface of a bare glass fiber with a fiber coating (one or two layers), and is in a form called an optical fiber core or an optical fiber. In addition, the multi-core optical fiber is referred to as an optical fiber tape or ribbon fiber in which a plurality of optical fiber cores or strands are integrated with a common coating.
[0016]
FIG. 1 is a view for explaining the outline of the present invention. FIG. 1 (A) is a sectional view of a cleaning apparatus, and FIGS. 1 (B) and 1 (C) are views for explaining an example of fiber holding. In the figure, 20 is an optical fiber, 20a is a bare fiber, 20b is a fiber coating, 21 is a fiber holder, 21a is a holder base, 21b is a holding lid, 21c is a hinge, 21d is an elastic member, 21e is a protruding piece, and 22 is cleaning. A tank, 23 is a cleaning liquid, 23a is a liquid surface, 24 is an ultrasonic generator, 25 is a float, 26 is a holding part, 26a is a storage recess, 27 is an opening, and 28 is a peripheral wall.
[0017]
Prior to fusion splicing of the optical fiber, the optical fiber 20 to be connected is stripped of the fiber coating 20b at the distal end to expose a bare fiber 20a of a predetermined length, and the end of the fiber coating 20b is connected to the fiber holder 21 or the like. Hold with. As shown in FIG. 1B, for example, the fiber holder 21 is configured such that a holding lid 21b is provided on a holder base 21a so as to be opened and closed by a hinge 21c. An elastic member 21d such as rubber is disposed on the inner surface of the holding lid 21b so that the optical fiber 20 can be gripped without applying an excessive pressure, and an attraction magnet (not shown) is embedded in the opening / closing surface. The holding state is maintained. The outer shape of the fiber holder 21 is not particularly limited, and may be a circular shape or an elliptical shape as shown in FIG.
[0018]
The cleaning device puts the cleaning liquid 23 into a circular or rectangular cleaning tank 22, generates ultrasonic vibrations in the cleaning liquid 23 with an ultrasonic generator 24 composed of a piezoelectric element or the like, and cleans the optical fiber 20 immersed in the cleaning liquid 23. It is configured to be washed. The float 25 is placed above the surface of the cleaning liquid 23. The float 25 is formed of a light metal such as aluminum or a synthetic resin, and is provided with a holding portion 26 for accommodating the fiber holder 21 at a central portion or an appropriate position of the float, and a peripheral wall 28 standing upright on the outer periphery of the float. I have.
[0019]
The holding portion 26 is formed with a storage recess 26 a for inserting and holding the fiber holder 21 from above, and communicates with the small-area opening 27 from which the cleaning liquid 23 is exposed. The storage recess 26 a can be tapered so that the fiber holder 21 can be easily inserted, or can be formed in a rectangular or circular shape adapted to the outer shape of the fiber holder 21. The gap between the peripheral wall 28 of the outer periphery of the float 25 and the side wall of the cleaning tank 22 is desirably formed to be a small gap (for example, about 1 mm) that does not hinder the vertical movement of the float 25. When the float 25 itself is lightweight and has sufficient buoyancy, the height of the peripheral wall 28 can be reduced or eliminated.
[0020]
When the exposed bare fiber 20a of the optical fiber 20 is cleaned by the cleaning device configured as described above, the fiber holder 21 is attached to the end of the optical fiber. Next, the fiber holder 21 is put in the storage recess 26 a of the holding unit 26, and placed on the float 25. The fiber holder 21 is positioned at the step of the storage recess 26a, and the bare fiber 20a from which the fiber coating 20b has been removed is immersed in the cleaning liquid 23 to a predetermined position through the opening 27 provided in the float 25, and is washed.
[0021]
2 and 3 are views showing specific examples of the cleaning device according to the present invention. In the figure, 30 is an adapter, 30a is an adapter base, 30b is a support portion, 30c is a guide portion, 30d is an attraction magnet, 30e and 30f are notches, and other symbols are the same symbols as used in FIG. The description is omitted by using this.
[0022]
This specific example shows an example in which the fiber holder 21 is held by the float 25 using the adapter 30. Further, as the fiber holder 21, one having a shape commonly used for removing or cutting or connecting an optical fiber can be used. The fiber holder 21 is formed, for example, on a vertically long holder base 21a having a protruding piece 21e, and provided with two holding lids 21b which can be opened and closed by hinges 21c. An elastic member 21d made of rubber or the like is arranged on the inner surface of the holding lid 21b so that the optical fiber 20 can be gripped without applying excessive pressure, and an attraction magnet (not shown) is embedded in the opening / closing surface. It is configured to hold a gripping state.
[0023]
The optical fiber 20 is securely gripped by the fiber holder 21 at the portion of the fiber coating 20b by the two holding lids 21b, and the bare fiber 20a is projected from the tip of the protruding piece 21e, leaving a slight fiber coating 20b. You. By holding the optical fiber 20 using the fiber holder 21 configured as described above, after removing the fiber coating and washing, the bare fiber 20a exposed without removing the optical fiber 20 from the fiber holder 21 is removed. It can be cut to length and set as it is in a fusion splicing device to perform fusion splicing.
[0024]
In the adapter 30, for example, the adapter base 30a and the support portion 30b are formed in an integral structure so that the outer peripheral surface is circular. The adapter base 30a is provided with a guide part 30c for accommodating the lower half of the fiber holder 21, and the support part 30b is formed with notches 30e and 30f for embedding the attraction magnet 30d and reducing the weight. The fiber holder 21 is positioned by the adapter 30 by the guide portion 30c and the attraction magnet 30d, and is detachably held.
[0025]
The float 25 is formed, for example, by drawing from an aluminum metal plate or the like into a circular cup shape having a small-diameter opening 27 at the center. The opening 27 is formed so as to protrude upward from a cylindrical pipe, and a cylindrical holding portion 26 is integrally formed at an upper end of the opening 27. The peripheral wall 28 of the float 25 is formed concentrically with the holding portion 26. As shown in FIG. 3, the cleaning tank 22 is formed in a circular cup shape with an upper end slightly enlarged, and a cleaning liquid 23 is filled therein. The peripheral wall 28 of the float 25 and the side wall of the cleaning tank 22 have a slight gap such that the float 25 can freely move up and down.
[0026]
When cleaning the bare fiber 20a of the optical fiber 20 with the cleaning apparatus configured as described above, the fiber holder 21 is attached to the end of the optical fiber. At this time, the end of the fiber coating 20b may be aligned with the tip of the protruding piece 21e as a reference or made to slightly protrude. Next, the fiber holder 21 is held by the adapter 30, and the adapter 30 is inserted into the storage recess 26 a of the holding portion 26 of the float 25. In the case where the outer peripheral surface of the adapter 30 is formed in a circular shape, no directionality is required when the adapter 30 is inserted into the holding portion 26, so that workability can be improved.
[0027]
The fiber holder 21 is positioned at the step of the storage recess 26 a of the holding unit 26 via the adapter 30, and the bare fiber 20 a from which the fiber coating 20 b has been removed is immersed in the cleaning liquid 23 through the opening 27 provided in the float 25. , Will be washed.
[0028]
1 and FIGS. 2 and 3, the liquid level of the cleaning liquid 23 is substantially covered by the contact of the lower surface of the float 25, and is exposed to the outside air only at the opening 27 and the float. This is a slight gap created between the outer periphery of the cleaning tank 25 and the cleaning tank 22. The liquid level 23a of the cleaning liquid 23 is determined by the buoyancy caused by the mass of the float 25, the fiber holder 21 and the adapter 30, and the relative distance between the fiber holder 21 and the liquid level 23a is constant. That is, the relative distance between the end of the fiber coating 20b of the optical fiber 20 and the liquid level 23a of the cleaning liquid 23 becomes constant.
[0029]
Therefore, even if the amount of the cleaning liquid 23 increases and decreases and the liquid level 23a fluctuates, the float 25 follows at the same time and the relative distance between the fiber holder 21 and the liquid level 23a does not change, as shown in FIG. There is no need to monitor the liquid level or adjust the position of the fiber holder in response to a change in the liquid level. For this reason, if the relative positional relationship is set in advance so that the fiber coating 20b of the optical fiber 20 does not touch the cleaning liquid 23, in a subsequent operation, the adjustment is performed within a predetermined range without adjustment regardless of the increase or decrease of the cleaning liquid 23. Only the bare fiber portion can be washed.
[0030]
In addition, when the above-described cleaning device is used in a place where there is shaking such as on a ship, the washing device itself also undergoes shaking, and the float 25 that is arranged floating on the washing liquid 23 also undergoes shaking. However, the liquid surface exposed for cleaning is the opening area of the opening 27 provided in communication with the holding section 26, and this opening area is sufficient to insert the optical fiber 20, and is increased. No need.
[0031]
Therefore, substantially no wave is generated in the small area portion of the opening 27, and it is suppressed to a negligible level, if any. Also, although the vertical fluctuation of the cleaning liquid surface due to the shaking occurs, the float 25 also fluctuates together with the vertical fluctuation of the cleaning liquid surface as described above, so that the relative distance between the fiber coating 20b of the optical fiber 20 and the cleaning liquid surface 23a. Can be maintained constant without change. By providing the opening 27 at the center of the float 25, fluctuations in the liquid level due to sudden shaking can be reduced. Further, by reducing the gap between the peripheral wall 28 of the float 25 and the cleaning tank 20 and increasing the height of the peripheral wall 28, the swing itself of the float 25 can be suppressed.
[0032]
For this reason, if the relative positional relationship is set in advance so that the fiber coating 20b of the optical fiber 20 does not touch the cleaning liquid 23, the cleaning liquid 23 is applied to the fiber coating 20b even if the cleaning device is suddenly shaken. Adhesion can be prevented.
[0033]
In the above-described cleaning apparatus, the area of the exposed cleaning liquid surface is reduced to prevent the liquid surface from waving, so that the cleaning tank 22 has a small volume. However, if the volume of the cleaning tank is small, the level of the cleaning liquid drops rapidly due to evaporation of the cleaning liquid, and even though it is not necessary to control the liquid level, the cleaning capacity decreases due to the contamination of the cleaning liquid, so the frequency of replacement increases, and the efficiency increases. Work may become impossible.
[0034]
FIG. 4 is a diagram illustrating an example of a cleaning tank having a large capacity that can cope with the above-described case. FIG. 4 (A) is a view schematically showing a cleaning tank, and FIG. 4 (B) is a view showing a state in which a float is arranged. In the figure, reference numeral 23 denotes a cleaning liquid, 25 denotes a float, 25 ′ denotes a dummy float, and 31 ′. Denotes a washing tank, 32 denotes a partition plate, 33 denotes a compartment, and 34 denotes an open channel part.
[0035]
As shown in the figure, the cleaning tank 31 is formed of, for example, a relatively large rectangular container, and the inside of the rectangular container is divided into a plurality of compartments 33 by a partition plate 32. The lower end of the partition plate 32 is floated from the bottom wall 31a of the washing tank 31 to provide an open channel section 34 so that the washing liquid 23 can freely move between the adjacent compartments 33. By dividing the cleaning tank 31 into a plurality of compartments 33, the exposed area of the cleaning liquid 23 can be reduced, and when used on a ship, generation of waves can be suppressed and the storage capacity of the cleaning liquid can be increased. is there.
[0036]
In the cleaning tank 31 configured as described above, the float 25 described above is disposed in the compartment 33 as shown as an example in FIG. The float 25 can be floated in the plurality of compartments 33 depending on the amount of work, and the plurality of optical fibers can be washed at the same time. By placing the dummy float 25 ′ or the like in the unused compartment 33, it is possible to prevent the washing liquid 23 from decreasing due to leakage due to evaporation or shaking. It should be noted that instead of the dummy float 25 ', a simple lid-shaped thing may be used. In each compartment, the partition wall may be formed in a cylindrical shape to form a cylindrical compartment, or the cleaning tank 31 itself may be formed of a circular container.
[0037]
【The invention's effect】
As described above, according to the present invention, with a simple configuration in which the float is floated on the cleaning liquid surface to hold the optical fiber, there is no need to adjust the holding position of the optical fiber with respect to the fluctuation of the cleaning liquid surface, and Even if the cleaning device itself shakes, the fiber coating can be cleaned without getting wet with the cleaning liquid, and the workability can be greatly improved without requiring the skill of the operator.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating an outline of the present invention.
FIG. 2 is a diagram illustrating a specific example of holding an optical fiber according to the present invention.
FIG. 3 is a diagram illustrating a cleaning mode according to a specific example of the present invention.
FIG. 4 is a diagram illustrating another example of the cleaning tank used in the present invention.
FIG. 5 is a diagram illustrating an example of a conventional cleaning device.
[Explanation of symbols]
Reference Signs List 20: optical fiber, 20a: bare fiber, 20b: fiber coating, 21: fiber holder, 21a: holder base, 21b: holding lid, 21c: hinge, 21d: elastic member, 21e: projecting piece, 22: cleaning tank, 23 ... cleaning liquid, 23a ... liquid surface, 24 ... ultrasonic generator, 25 ... float, 25 '... dummy float, 26 ... holding part, 26a ... storage concave part, 27 ... opening part, 28 ... peripheral wall, 30 ... adapter, 30a ... Adapter base, 30b: support, 30c: guide, 30d: attracting magnet, 30e, 30f: notch, 31: washing tank, 31a: bottom wall, 32: partition, 33: compartment, 34: open channel.

Claims (10)

An optical fiber cleaning apparatus for immersing a coating removal portion of a single-core or multi-core optical fiber end portion in a cleaning solution and cleaning it by ultrasonic vibration, comprising a float floating on a cleaning solution in a cleaning tank, wherein the float An optical fiber cleaning apparatus, further comprising: a holding portion for immersing a coating removal portion at an end of the optical fiber in the cleaning liquid to hold the portion. The optical fiber cleaning apparatus according to claim 1, wherein a cylindrical opening for exposing a cleaning liquid is provided at a center of the float. The optical fiber cleaning apparatus according to claim 1, wherein an outer circumference of the float has a shape in which a slight gap is formed between the float and an inner wall of the cleaning tank. The optical fiber cleaning apparatus according to claim 1, wherein the holding unit is configured to detachably hold a fiber holder that holds the optical fiber in a longitudinal direction. The optical fiber cleaning apparatus according to claim 1, wherein the holding unit is configured to detachably hold an adapter that fixes a holding tool that holds the optical fiber in a longitudinal direction. The optical fiber cleaning device according to claim 4, wherein the fiber holder for gripping the optical fiber in the longitudinal direction has a shape commonly used for removing, cutting, or connecting the optical fiber. apparatus. The optical fiber cleaning apparatus according to claim 5, wherein the outer shape of the adapter is circular. The optical fiber cleaning apparatus according to any one of claims 1 to 3, wherein the cleaning tank is divided into a plurality of compartments by a partition wall. An optical fiber cleaning method of immersing a coating removal portion of a single-core or multi-core optical fiber end portion in a cleaning solution and cleaning it by ultrasonic vibration, wherein a float is floated on a cleaning solution in a cleaning tank, and the light is applied to the float. An optical fiber cleaning method, comprising holding a fiber end portion and immersing a coating removal portion of the optical fiber end portion in the cleaning liquid. The optical fiber cleaning method according to claim 9, wherein the coating-removed portion is immersed in the cleaning liquid at a cylindrical opening provided at the center of the float and exposing the cleaning liquid.

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