JP2003075650A - Device and method for cutting optical fiber - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device and a method for cutting an optical fiber which enable cutting of a strongly connected optical fiber with the use of a cutting device for a conventionally connected optical fiber (a method using a pressurizing block). SOLUTION: By the method for cutting optical fiber, the optical fiber 1 of which coat is removed at the end part and the glass fiber part 2 is exposed is held and fixed with a pair of clamps 4, the glass fiber part 2 is bruised with a bruising blade 6 and the optical fiber 1 is cut by pressurizing the bruised part 6a with the pressurizing block 5. The coated part 3 of the fiber is held with one of the clamps 4a which holds and fixes the optical fiber 1, the pressurizing block 5 has a pair of pressurizing legs 5a and 5b, one pressurizing leg 5a is pressed against the end part of the coated fiber 3 and the other pressurizing leg 5b is pressed against only the glass fiber part 2 which is disposed of after being cut in the vicinity of the bruised part 6a.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical fiber cutting device and a cutting method for performing a pretreatment when splicing optical fibers.

[0002]

2. Description of the Related Art Submarine optical fiber cables are subject to severer conditions than land-based optical fiber cables because of their installation environment. Submarine optical cables are generally spliced together for longer distances, but a large tension is applied when the optical cable is laid or pulled up. For this reason, recently, a fusion splicing method called high-strength splicing has been used for fusion splicing of optical fibers.

FIG. 4 is a diagram for explaining a normal connection and a high strength connection in the fusion splicing. In the figure, 1 is an optical fiber, 2
Is a glass fiber part, 3 is a fiber coating, 4 is a fiber clamp, 5 is a pressing pillow, 6 is a scratching blade, and 7 is a V groove stand. The outlines of the normal connection and the high-strength connection steps are as follows: the coating removal step S1 for the fiber coating, the glass fiber surface cleaning step S2, the cutting step S3 for forming the connection end face, the optical fiber fusion step S4, and the fusion spliced portion are reinforced. It comprises a reinforcing step S5.

The fundamental difference between the normal connection and the high-strength connection is that the normal connection has a physical contact with the surface of the glass fiber portion 2 from which the coating is removed during the manufacturing process, whereas the high-strength connection is different from the normal connection. In principle, there is no physical contact. As a result, the high-strength connection can be made without damaging the surface of the glass fiber portion 2, and the final tensile strength can be increased. The differences between the steps will be described below.

In the coating removal step S1, the glass coating 2 is removed by removing the fiber coating 3 on the connection end side of the optical fiber 1.
Is exposed by a coating remover (not shown). In the case of normal connection, the fiber coating 3 is not heated, but in the case of high strength connection, the fiber coating 3 is heated and softened. By softening the fiber coating 3 that is in close contact with the surface of the glass fiber, the coating can be easily removed and the glass fiber portion 2 can be removed without being scratched.

The cleaning step S2 is an operation for removing the residue left over after the fiber coating 3 is removed. Generally, in normal connection, it is wiped off with alcohol-soaked gauze or the like, whereas in high-strength connection, it is soaked in acetone solution and ultrasonically cleaned. By ultrasonic cleaning, the surface of the glass fiber part 2 can be cleaned without being scratched by a wiping operation.

The cutting step S3 is an operation for forming a connection end face on the glass fiber portion 2. In this cutting operation, it is necessary to cut from the end of the fiber coating 3 at a predetermined position, the cutting surface should be smooth like a mirror surface, and cut at a right angle to the optical fiber axis. In the normal connection, both sides of the exposed glass fiber portion 2 are pressed by the fiber clamps 4, the glass fiber portion 2 is scratched by hitting the scratching blade 6 from below, and the pressing pillow 5 is pushed down from above and the glass fiber portion 2 is pressed. Bend, enlarge the damaged part and cut.

On the other hand, in the high-strength connection, the optical fiber portion on the use side presses the fiber coating 3 with the fiber clamp 4, and the glass fiber portion on the side discarded after cutting is directly fiber clamped as in the normal connection. Hold with 4. Then, the glass fiber portion 2 is scratched by the scratching blade 6 in a state where tensile tension is applied to the optical fiber 1 between the fiber clamps 4 on both sides. The damaged scratch is enlarged and cut by the tensile tension applied to the glass fiber portion 2.
According to this cutting method, the glass fiber portion 2 on the side to be used is not scratched by the clamp, and the distance between the fiber coating 3 and the cut end face can be shortened.

The fusion step S4 is an operation of placing the cut optical fibers on a fusion splicer and fusing them.
In a normal connection, the glass fiber portion 2 is placed on the V-groove base 7 for positioning, and the fiber coating 3 is also clamped, held and fixed, and after alignment and the like, the connection end is heated and melted by melting by arc discharge or the like. Connect. In high-strength connection, the portion of the fiber coating 3 is directly placed on the V-groove base 7 to perform positioning, holding and fixing, and after performing positioning and the like,
The connection end is heated and melted by arc discharge or the like to perform fusion splicing. As a result, the glass fiber portion 2 is not damaged by the clamp, and the distance between the fiber coating 3 and the fusion splicing portion can be shortened.

The reinforcing step S5 is an operation for mechanically reinforcing the glass fiber portion 2 and the fusion splicing portion, the strength of which has been reduced by removing the fiber coating. As a reinforcing method, there are various methods using a heat shrinkable tube, hot melt, a mold and the like. Generally, a normal connection is reinforced with a reinforcing sleeve of about 60 mm, and the tensile strength is about 0.2 kg. On the other hand, if high strength connection is used, 3
It is reinforced with a reinforcing sleeve of about 0 mm, and the tensile strength is 1 kg or more, and the tensile strength 5 times or more that of the normal connection can be obtained.

As described above, the high-strength connection can obtain a result suitable for connection of a submarine optical cable or the like as compared with the normal connection, but there is a problem in the cutting method used in the cutting step S3. The cutting device for high strength connection is more expensive (about 5 times) than the cutting device for normal connection,
The cutting characteristics (cutting success rate) are not very good.

[0012]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned circumstances, and an optical fiber cutting device for normal connection (method using a pressing pillow) is used to cut an optical fiber for high strength connection. It is an object of the present invention to provide an optical fiber cutting device and a cutting method that enable the above.

[0013]

The optical fiber cutting device of the present invention includes a pair of clamps for holding and fixing an optical fiber having a glass fiber portion exposed by removing the coating of the end portion, and the glass fiber portion is scratched. An optical fiber cutting device comprising a scratching blade for pressing and a pressing pillow for pressing the damaged portion, wherein one clamp for holding and fixing the optical fiber is arranged to hold the fiber coating portion, and the pressing pillow is It has a pair of pressing legs, one pressing leg hits the end of the fiber coating, and the other pressing leg is arranged so as to hit only the glass optical fiber part discarded after cutting near the damaged part And

Further, according to the optical fiber cutting method of the present invention, the optical fiber from which the coating is removed to expose the glass fiber portion is held and fixed by a pair of clamps, and the glass fiber portion is added with a scratching blade. A method of cutting an optical fiber by pressing a pillow that is damaged and pressing a damaged part, in which one clamp holding the optical fiber holds the fiber coating portion, and the pressing pillow has a pair of pressing legs. The present invention is characterized in that one pressing leg is applied to the end of the fiber coating and the other pressing leg is applied only to the glass fiber portion which is discarded after being cut in the vicinity of the damaged portion.

[0015]

DETAILED DESCRIPTION OF THE INVENTION An embodiment of the present invention will be described with reference to FIG. In the figure, 1 is an optical fiber, 2 is a glass fiber part, 3 is a fiber coating, 4 is a fiber clamp, and 4a.
Is a coated fiber clamp, 4b is a glass fiber clamp, 5 is a pressing pillow, 5a and 5b are pressing legs, 6 is a wound blade, 6
a is a damaged part, 10 and 12 are bases, and 11 and 13 are holding members.

In the present invention, the optical fiber for high-strength connection is cut using the pressing pillow 5 and the scratching blade 6 which are normally used for connection. That is, both sides of the cut portion of the optical fiber 1 are held and fixed by using a pair of fiber clamps 4, the scratched blade 6 is arranged below the cut portion of the glass fiber portion 2, and the pressing pillow 5 is arranged above. Is. The cutting method is as follows. After fixing both sides of the cut portion of the optical fiber 1 with the fiber clamps 4, a scratching blade 6 is applied to the cut portion of the glass fiber portion 2 from below the optical fiber to scratch and then the scratched blade. 6 is moved downward and the pressing pillow 5 is pushed downward. By the pressing of the pressing pillow 5, the optical fiber 1 is bent downward, and the scratches scratched by the scratch blade 6 are enlarged and cut.

The optical fiber 1 is held and fixed with one coated fiber clamp 4a by holding and fixing the vicinity of the end of the fiber coating 3 on the side to be cut and used. The other glass fiber clamp 4b directly holds and fixes the end portion of the glass fiber portion 2 on the side to be discarded after cutting. The method for holding and fixing the optical fiber is the same as the method for cutting the optical fiber used in the high strength connection described in FIG. However, in the coated fiber clamp 4a, the inner end surface 11a of the upper pressing member 11 is made to coincide with the inner end surface 10a of the lower base table 10. The other glass fiber clamp 4
The b side may be configured similarly, but is not particularly limited to this. The lower bases 10 and 12 can be easily positioned by forming the V-grooves.

As the pressing pillow 5, one having a shape having two pressing legs 5a and 5b straddling both sides of the damaged portion 6a is used.
In the present invention, the one pressing leg 5a is configured and arranged so as to contact the fiber coating 4 of the optical fiber 1, and the other pressing leg 5b is configured and arranged so as to contact only the glass fiber portion discarded in the vicinity of the damaged portion 6a. . Since there is a step between the glass fiber portion 2 and the fiber coating 3 as shown in the figure, it is preferable that the pressing leg 5a on the side that contacts the fiber coating 3 is formed to have a length corresponding to the coating thickness X and shorter than the other pressing leg 5b. Also,
The inner distance Y between the pressing legs 5a and 5b is formed to be larger than the distance Z between the end of the fiber coating 3 and the damaged portion 6a. In the high strength connection, the distance Z between the end of the fiber coating 3 and the damaged portion 6a is generally set to 4 mm or less.

As a concrete example of the embodiment of the present invention, the bases 10 and 12 of the fiber clamp 4 are formed by V-grooves, and the optical fiber 1 is held and fixed. The distance Z between the end of the fiber coating 3 and the damaged portion 6a is 3.0 mm, and the inner distance Y between the pressing legs 5a and 5b of the pressing pillow 5 is 4.5 mm.
And In addition, the step X between the pressing legs 5a and 5b is 0.06 m.
m, and the lowering amount of the pressure pillow 5 is 0.5 compared to the normal case.
It was verified by reducing mm.

FIG. 2 is a diagram showing the above verification results.
FIG. 2A is a diagram showing a cutting failure, and FIG. 2B is a diagram showing a graph of verification results. For verification, two workers each performed a cutting work of 40 samples, a total of 80 samples, and checked the cutting angle and the presence or absence of a cut portion. The cutting angle is 1 ° with respect to the plane perpendicular to the optical fiber axis.
Less than was regarded as successful, and when there was a chip, it was regarded as defective.

As shown in FIG. 2B, there was no substantial difference in the quality of the cutting result depending on the skill of the operator. One sample has a poor angle for a total of 80 samples of two people,
There are 5 samples for chipping defects and 6 samples for cutting defects.
The defective rate was 7.5% and the cutting success rate was 92.5%, and very good results could be obtained. In addition, about 20 samples of successful products, fusion splicing is performed and reinforcement treatment is applied,
The tensile strength was measured. As a result, the maximum value is 2.41k
It was also clarified that g, the minimum value of 1.37 kg, and the average value of 1.86 kg sufficiently satisfy the condition of 1 kg or more for high strength connection.

FIG. 3 is a diagram showing a comparative example of the present invention.
3A is a diagram showing an example in which the width of the pressing pillow is widened and one side is applied to the fiber coating portion, FIG. 3B is a diagram showing an example in which the pressing pillow is applied only to the optical fiber on the discarding side, and FIG. It is a figure which shows the example which changed the state of the coated fiber clamp from this invention. In each of the comparative examples, the pressing pillow was in a form of contacting only the glass fiber portion on the side discarded after cutting. The reference numerals are the same as those in FIG. 1, and detailed description thereof will be omitted.

In the comparative example of FIG. 3A, the width of the pressing pillow 5 is widened so that the pressing leg 5a of the pressing pillow 5 does not hit the glass fiber portion 2, and the inner distance Y between the pressing legs 5a and 5b is set to 6. 0m
m. Further, similarly to the specific example of the present invention,
The difference X in length between the pressing legs 5a and 5b was set to 0.06 mm, and the distance Z between the end of the fiber coating 3 and the damaged portion 6a was set to 3.0 mm. The coated fiber clamp 4a is
Although the V-groove base 10 and the pressing member 11 were used, the inner end surface 11a of the pressing member 11 was held and fixed in a normal clamp form in which it was displaced outward from the inner end surface 10a of the base 10. When 20 samples were cut and the cutting characteristics were examined, 12 samples were found at a cutting angle of less than 1 °. Of these, 3 samples had chipping defects and 9 samples were successful and the cutting success rate was 45%. there were.

In the comparative example of FIG. 3B, the clamp form of the optical fiber and the distance Z between the end of the fiber coating 3 and the damaged portion 6a are set to 3.0 mm, which is the same as in FIG. The pressing form of was changed. The pressing pillow 5 in this case has a damaged portion 6a.
Only the glass fiber portion 2 discarded after cutting in the vicinity of is hit. When 20 samples were cut in this form and the cutting characteristics were examined, 0 samples were found at a cutting angle of less than 1 °, and the cutting success rate was 0%.

In the comparative example of FIG. 3C, the clamp form of the optical fiber and the distance Z between the end of the fiber coating 3 and the damaged portion 6a are set to 0.3 mm, which is the same as in FIG. The same one used in the present invention was used. As a result, 38 out of 40 samples had a cutting angle of less than 1 °.
The sample has chipping defects and the cutting success rate is 77.5%.
Then, the defect rate was 20%. As a result of investigating the cause of the large number of chipping defects, it was found that the optical fiber 1 floats up at the end of the base 10 as shown in the figure surrounded by a square frame. It is conceivable that this floating causes chipping when the optical fiber is cut. With a normal high-strength clamp, even if the inner end surface 11a of the upper pressing member 11 is slightly displaced from the inner end surface 10a of the base, there is no problem in cutting with tension.
It is considered to be a problem when cutting using the pressing pillow 5.

The optical fiber cutting apparatus and the cutting method of the present invention have been described above with reference to an example of application to high-strength fusion splicing. However, when obtaining a cut end face with a short exposed length of the glass fiber portion, it is general. The present invention can also be applied to the above-mentioned ordinary fusion splicing and the formation of connection ends of other optical components.

[0027]

As is apparent from the above description, according to the present invention, a cutting end face having a short exposed length of the glass fiber portion can be cut at a low cost by using a scratching blade and a pressing pillow. , It is possible to cut without damaging the glass fiber part. Further, this can increase the success rate of cutting and improve workability.

[Brief description of drawings]

FIG. 1 is a diagram illustrating an embodiment of the present invention.

FIG. 2 is a diagram showing a verification result of the present invention.

FIG. 3 is a diagram showing a comparative example of the present invention.

FIG. 4 is a diagram illustrating a work process of a normal connection and a high-strength connection of a conventional fusion splicing.

[Explanation of symbols]

1 ... Optical fiber, 2 ... Glass fiber part, 3 ... Fiber coating, 4 ... Fiber clamp, 4a ... Coated fiber clamp, 4b ... Glass fiber clamp, 5 ... Press pillow, 5
a, 5b ... pressing leg, 6 ... wound blade, 6a ... wound portion, 10,
12 ... Base stand, 11, 13 ... Holding member.

Continued front page    (72) Inventor Kiyofumi Shimada             Sumitomoden 1 Taya-cho, Sakae-ku, Yokohama-shi, Kanagawa             Ki Industry Co., Ltd. Yokohama Works (72) Inventor Tatsu Sakimoto             Sumitomoden 1 Taya-cho, Sakae-ku, Yokohama-shi, Kanagawa             Ki Industry Co., Ltd. Yokohama Works (72) Inventor Kenji Kobayashi             Sumitomoden 1 Taya-cho, Sakae-ku, Yokohama-shi, Kanagawa             Ki Industry Co., Ltd. Yokohama Works (72) Inventor Hiroshi Sasaki             Sumitomoden 1 Taya-cho, Sakae-ku, Yokohama-shi, Kanagawa             Ki Industry Co., Ltd. Yokohama Works (72) Inventor Norio Ito             Sumitomoden 1 Taya-cho, Sakae-ku, Yokohama-shi, Kanagawa             Ki Industry Co., Ltd. Yokohama Works (72) Inventor Yoshiaki Yamada             Sumitomoden 1 Taya-cho, Sakae-ku, Yokohama-shi, Kanagawa             Ki Industry Co., Ltd. Yokohama Works F-term (reference) 2H038 CA02 CA12

Claims (7)

[Claims] 1. A pair of clamps for holding and fixing an optical fiber having a glass fiber portion exposed by removing a coating on an end portion, a scratching blade for scratching the glass fiber portion, and a pressing portion for the scratched portion. An optical fiber cutting device including a pressing pillow for holding, wherein one clamp for holding and fixing the optical fiber is arranged to hold a fiber coating portion, the pressing pillow has a pair of pressing legs, and 2. The optical fiber cutting device according to claim 1, wherein the pressing leg of is contacted with an end portion of the fiber coating, and the other pressing leg is arranged so as to contact only the glass fiber portion discarded after cutting in the vicinity of the damaged portion. 2. The one clamp for holding the fiber coating portion comprises a base and a pressing member, and is formed so that an inner end surface of the base and an inner end surface of the pressing member are aligned with each other. The optical fiber cutting device according to claim 1. 3. The optical fiber cutting device according to claim 2, wherein the optical fiber mounting surface of the base is formed with a V groove. 4. The one pressing leg is formed to be shorter than the other pressing leg by an amount corresponding to a thickness of the fiber coating. Optical fiber cutting device. 5. An optical fiber whose glass fiber portion is exposed by removing the coating on the end portion is held and fixed by a pair of clamps, the glass fiber portion is scratched by a scratch blade, and the scratched portion is pressed. An optical fiber cutting method of cutting an optical fiber by pressing a pillow, wherein one clamp holding and fixing the optical fiber holds a fiber coating portion, and the pressing pillow has a pair of pressing legs, and one pressing An optical fiber cutting method, wherein a leg is applied to an end of the fiber coating, and the other pressing leg is applied only to a glass fiber portion which is discarded after being cut in the vicinity of the damaged portion. 6. The optical fiber cutting method according to claim 5, wherein the one clamp for holding the fiber coating portion is held and fixed such that the inner end surfaces of the base and the pressing member are aligned with each other. . 7. The optical fiber cutting method according to claim 5, wherein the distance between the end of the fiber coating and the damaged portion is 4 mm or less.