KR19990061841A - Fiber optic extractor - Google Patents

Abstract

Disclosed is an optical fiber drawing apparatus which enables to extract an optical fiber having an improved polarization mode dispersion (PMD) characteristic when the optical fiber is drawn.

The optical fiber drawing device is a melting furnace which melts an optical fiber base material so that the optical fiber is drawn out, a cooling device which cools the optical fiber drawn out of the melting furnace to an appropriate temperature, a coating device which coats the cooled optical fiber, and cures the coated optical fiber. And a capstan for controlling the extraction speed of the optical fiber by adjusting the tension of the optical fiber according to the rotation thereof, and an optical fiber twisting device installed between the curing device and the capstan to twist the optical fiber at a constant cycle. The housing is provided with a base, a housing formed with a through hole through which the optical fiber moved from the curing apparatus to the capstan is slidable, a plurality of rollers contacting the optical fiber passing through the through hole and rotatably installed in the housing, It is linked to the rotation of this housing by rotating it by a predetermined angle. By the rotation of the roller it characterized in that it comprises a pivoting means that allows the optical fiber can be twisted.

Since the optical fiber drawing device twists the optical fiber at the time of optical fiber drawing, it is possible to manufacture an optical fiber having a small average value of the polarization mode dispersion.

Description

Fiber optic extractor

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical fiber drawing device, and more particularly, to an optical fiber drawing device which is capable of extracting an optical fiber having an improved polarization mode dispersion (PMD) characteristic upon optical fiber drawing.

In general, optical fibers are used to transmit optical information signals in optical communication. Polarization mode dispersion may occur during optical transmission using such an optical fiber, which is due to birefringence due to the non-circularity of the optical fiber core drawn from the optical fiber base material. When the core of the optical fiber is elliptical, the transmission speed of the transmitted light for two orthogonal polarizations is changed, thereby causing dispersion due to polarization mode delay.

This polarization mode dispersion distorts the optical information signal, and therefore, loss occurs due to the dispersion of the signal by the optical fiber during transmission of a high quality analog signal and a high speed digital signal, thereby making it difficult to transmit the information signal. Therefore, in order to transmit the original optical information signal without distortion of the signal, an optical fiber having a polarization mode dispersion as low as possible is required.

A conventional optical fiber drawing device for manufacturing an optical fiber with low polarization mode dispersion is shown in FIG.

Referring to the drawings, the optical fiber base material 10 is melted to a sufficient temperature in the melting furnace 20 and drawn out to the optical fiber 15. The drawn optical fiber 15 is cooled to a predetermined temperature suitable for coating the optical fiber 15 while passing through the cooling device 21. The cooled optical fiber 15 is coated with a polymer coating while passing through the coating device 22. The coated optical fiber 15 is cured while passing through the ultraviolet curing device 24, and then wound through the capstan 40 to be wound on a winder (not shown). Here, the capstan 40 controls the output speed of the optical fiber 15 by adjusting the tension of the optical fiber 15 in accordance with the rotation.

On the other hand, the concentricity check unit 23 provided between the coating device 22 and the curing device 24 checks the concentricity of the optical fiber 15 and the coating via the coating device 22. Then, an optical fiber diameter detection unit 25 is provided at the stage next to the curing device 24 to detect the diameter of the cured optical fiber 15 while passing through the curing device 24.

In addition, between the curing device 24 and the capstan 40, as shown in Figure 2, the optical fiber twist device 30 is composed of a plurality of guide rollers 33, 34, 35 is provided. The first guide roller 33 can be freely rotated about its rotation axis, and is installed on the base 31 so that the rotation axis can be moved within a predetermined angle range by a predetermined means. The remaining second and third guide rollers 34 and 35 are installed on the base 31 so as to be freely rotated about the rotation axis thereof and guide the optical fiber 15.

In the optical fiber twist device 30 provided as described above, the movement of the first guide roller 33 provides a rotational force to the optical fiber 15, whereby the optical fiber 15 is twisted.

At this time, when the first guide roller 33 periodically moves within a predetermined angle range, the optical fiber 15 is periodically twisted. Since the optical fiber 15 periodically twisted in this way is uniformly stressed in the circumferential direction, the polarization mode dispersion characteristic is improved.

However, as shown in FIG. 3 due to the movement of the optical fiber 15 generated by the movement of the first guide roller 33, a predetermined range (from the original position of the optical fiber 15) d ) Deviation occurs. This deviation causes a problem that the center of the optical fiber 15 via the coating device 22 and the coating do not coincide.

Further, as shown in FIG. 2, the optical fiber 15 is moved from the original position by a predetermined range due to the movement of the optical fiber 15 linked to the movement of the first guide roller 33. d The deviation is generated by), and the displacement (length) of the optical fiber 15 is increased by this deviation, so that the tension of the optical fiber 15 is increased, and thus the outer diameter of the optical fiber 15 is changed.

In addition, since the optical fiber 15 may slide along the surface of the first guide roller 33 when the first guide roller 33 moves, the twist of the optical fiber 15 is not made constant.

The present invention has been made in view of the above points, and an object thereof is to provide an optical fiber drawing device employing an optical fiber twisting device which twists the optical fiber periodically while maintaining the original position of the optical fiber.

1 is a view schematically showing a conventional optical fiber drawing device,

Figure 2 is a schematic view of the optical fiber twist device of Figure 1,

3 is a view showing the deviation of the optical fiber generated by the guide roller of FIG.

4 is a schematic view of an optical fiber drawing device according to an embodiment of the present invention;

Figure 5 is a perspective view schematically showing the optical fiber twist device of Figure 4,

6 is a plan view of FIG. 5;

7 is a perspective view schematically showing the inside of the housing of FIG.

Explanation of symbols for main parts of the drawings

10 ... optical fiber base 20 ... melting furnace

21 ... Cooling Unit 22 ... Clearing Unit

24 Curing device 40 Capstan

45 ... optical fiber 50 ... optical fiber twist

51 ... Base 55 ... Housing

56 ... through 60 ... roller

61,62,63,67,68 ... support roller 64,65,66 ... push roller

70 Driving means 71 Driving source

72 Cam member 73 Elastic member

75.Rotating member 75a ... Hinge shaft

77,78 ... Link member 80 ... X-Y stage

In order to achieve the above object, an optical fiber drawing device according to the present invention includes a melting furnace for melting an optical fiber base material to draw an optical fiber, a cooling device for cooling the optical fiber drawn out of the melting furnace to an appropriate temperature, and coating the cooled optical fiber. A coating device for coating the optical fiber, a curing device for curing the coated optical fiber, a capstan for controlling the drawing speed of the optical fiber by adjusting the tension of the optical fiber according to the rotation thereof, and installed between the curing device and the capstan to provide the optical fiber. An optical fiber drawing device comprising a fiber twisting device twisted at a predetermined cycle, the optical fiber twisting device comprising: a base; A housing slidably installed in the base and having a through hole through which an optical fiber moved from the curing apparatus toward the capstan is formed; A plurality of rollers contacting the optical fiber passing through the through hole and rotatably installed in the housing; Rotating means for rotating the housing by a predetermined angle, so that the optical fiber can be twisted by the rotation of the plurality of rollers linked to the rotation of the housing.

Here, the plurality of rollers, and a plurality of support rollers for supporting the optical fiber passing through the through hole does not deviate from the original position; And a plurality of pushing rollers disposed between the support rollers so that the optical fiber does not slip and comes into close contact with the support rollers so as to be interlocked with the rotation of the housing to twist the optical fiber.

At this time, the support roller is composed of the first, second, third and fourth support rollers arranged in sequence, the first and third support rollers or the second and fourth support rollers along one side of the optical fiber It is preferably arranged side by side, the remaining two support rollers are preferably arranged side by side along the other side orthogonal to one side of the optical fiber.

In addition, the pushing roller consists of first and second pushing rollers sequentially arranged, one pushing roller of the first and second pushing roller is disposed on one side of the optical fiber, the other pushing roller is one side of the optical fiber It is preferable to arrange | position on the other side orthogonal to.

Here, the rotation means, the drive source provided on the base; A cam member installed on a rotation shaft of the drive source and driven by the drive source; A rotating member rotatably installed on the base, the rotating member being rotated about the hinge axis according to the rotation of the cam member; An elastic member installed at one side of the pivot member to elastically bias the pivot member toward the cam member; And a link member installed between the housing and the rotating member to reciprocate the housing by a predetermined angle according to the rotation of the rotating member.

On the other hand, the optical fiber twisting device, the XY stage for adjusting the position of the housing so that the rotation axis of the optical fiber and the housing penetrated by adjusting the base in the X-direction and Y-direction; Do.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

4 is a view schematically showing an optical fiber drawing device according to an embodiment of the present invention.

Referring to the drawings, the optical fiber drawing device includes a melting furnace 20 to draw the optical fiber 45 from the optical fiber base material 10, a cooling device 21 for cooling the drawn optical fiber 45 to an appropriate temperature, and A coating device 22 for coating the cooled optical fiber 45, a curing device 24 for curing the coated optical fiber 45, a capstan 40 for controlling the drawing speed of the optical fiber 45, and It is configured to include an optical fiber twisting device 50 to twist the optical fiber 45 at a predetermined period. Here, the same reference numerals as those in FIG. 1 denote the same members having the same function, and thus detailed description thereof is omitted.

As shown in FIG. 5, the optical fiber twisting device 50 is installed on a path of the optical fiber 45 between the curing device 24 and the capstan 40 to twist the optical fiber 45 at regular intervals. The optical fiber twist device 50 includes a base 51, a housing 55 slidably mounted on the base 51, a plurality of rollers 60 rotatably installed on the housing 55, and the housing. And rotating means 70 for rotating the 55 by a predetermined angle.

The through hole 56 is formed in the housing 55 to allow the optical fiber 45 to move from the curing apparatus 24 toward the capstan 40. The optical fiber 45 penetrating through the housing 55 forms a straight line from the point drawn out from the melting furnace 20.

4, 6 and 7, the plurality of rollers 60 are rotatably installed in the housing 55 and are in contact with the optical fiber 45 passing through the through hole 56. . The plurality of rollers 60 are disposed between the plurality of support rollers 61 and the support rollers 61 for supporting the optical fiber 45 passing through the through hole 56 so as not to be out of their original positions. 45 includes a plurality of pushing rollers 64 which are coupled to the support roller 61 without slipping so that the optical fiber 45 can be twisted in conjunction with the rotation of the housing 55.

The support roller 61 is composed of four support rollers, that is, first, second, third and fourth support rollers 62, 63, 67 and 68 sequentially arranged as shown. The first and third support rollers 62 and 67 are disposed side by side along one side of the optical fiber 45. Referring to FIG. 4, the first and third support rollers 62 and 67 may be arranged such that the rotation axis thereof is initially parallel to the rotation axis of the capstan 40, and the optical fiber 45 is in one direction. , so that it does not move in the -y direction.

The second and fourth support rollers 63 and 68 are arranged side by side along the other side orthogonal to one side of the optical fiber 45 on which the first and third support rollers 62 and 67 are disposed. The second and fourth support rollers 63 and 68 may have their rotation axes orthogonal to the rotation axes of the capstan 40 at an initial stage, and the optical fiber 45 moves in another direction, that is, the -x direction. Support not to be.

The pushing roller 64 is composed of first and second pushing rollers 65 and 66 sequentially disposed between the second and third supporting rollers 63 and 67. The first and second pushing rollers 65 and 66 allow the optical fiber 45 to be twisted by being in close contact with the support roller without slipping. To this end, the first pushing roller 65 is one side of the optical fiber 45, that is, the optical fiber in a direction opposite to the direction in which the first and third support rollers 62, 67 are in contact with the optical fiber 45 It is arranged to contact 45. The second pushing roller 66 is opposite to the other side orthogonal to the first pushing roller 65, that is, the direction in which the second and fourth supporting rollers 63 and 68 are in contact with the optical fiber 45. It is arranged to contact the optical fiber 45 in the direction. Therefore, the first pushing roller 65 initially supports the optical fiber 45 not to move in the y direction, and the second pushing roller 66 initially moves the optical fiber 45 in the x direction. Support not to be.

Here, the plurality of rollers 60 are described as being divided into the support roller 61 and the pushing roller 64, but the functions are not clearly distinguished, and the rollers 60 are combined with each other to form an optical fiber. Make sure that (45) can be twisted without leaving its original position. In addition, although the rollers 60 are formed of six rollers, the arrangement and function of the rollers have been described with reference to FIGS. 4, 6, and 7, but are not limited thereto. That is, it is possible to employ three or more rollers so that the optical fiber 45 can be twisted without deviating from its original position, and the arrangement can also be variously modified.

The rotating means (70) is such that the housing (55), in which a plurality of rollers (60) are rotatably installed, slides on the base (51) and rotates at a predetermined angle with respect to the central axis thereof. The optical fiber 45 is twisted by the plurality of rollers 60 interlocked in the rotation of the. To this end, the rotation means 70 is rotated in accordance with the rotation of the drive source 71 installed in the base 51, the cam member 72 driven by the drive source 71, and the cam member 72 The rotating member 75, the elastic member 73 for elastically biasing the rotating member 75 toward the cam member 72, and the housing 55 by a predetermined angle according to the rotation of the rotating member 75. And link members 77 and 78 for reciprocating rotation.

The cam member 72 is installed on the rotation shaft of the drive source 71. The rotating member 75 is rotatably installed on the base 51 around the hinge shaft 75a and reciprocated in accordance with the rotation of the cam member 72. In this case, the hinge shaft 75a is preferably provided on a vertical line formed by the rotation shaft of the housing 55 and the rotation member 75. The elastic member 73 is installed on one side of the rotating member 75 to elastically bias the rotating member 75 toward the cam member 72. 4 and 5 show an example in which the elastic member 73 is installed between the base 51 and the rotation member 75 so as to face the cam member 72.

The link members 77 and 78 are installed between the housing 55 and the rotation member 75. As shown, the link members 77 and 78 are provided in a pair symmetrically with respect to the hinge axis 75a. The pair of link members 77 and 78 are slidably coupled to the pivot member 75 and the housing 55, respectively. That is, one of the link members 77 and 78 and the rotating member 75 is provided with a projection (75b) and the other is provided with a long hole (77a) to be slidably fitted. 5 and 6 show an example in which the protrusion 75b is provided on the pivot member 75 and the long hole 77a is provided on the link members 77 and 78. In addition, one of the link members 77 and 78 and the housing 55 is provided with a projection is formed on the other side is provided with a long hole that the projection is slidably fitted. As described above, the pair of link members 77 and 78 connecting the housing 55 and the rotation member 75 may be formed by reciprocating rotation of the rotation member 75 according to rotation of the cam member 72. The housing 55 is reciprocated by a predetermined angle.

On the other hand, the optical fiber twist device 50 preferably further comprises an X-Y stage 80 to adjust the base 51 in the x- and y-direction. The X-Y stage 80 adjusts the position of the base 51, that is, the housing 55, so that the center axis of the optical fiber 45 and the housing 55, that is, the rotation axis, which are drawn out coincide with each other.

The optical fiber base material 10 mounted in the optical fiber 45 withdrawing apparatus according to the present invention provided as described above is melted at a sufficient temperature in the melting furnace 20 and drawn out to the optical fiber 45. The drawn optical fiber 45 is cooled while passing through the cooling device 21 and coated with a polymer coating while passing through the coating device 22. The coated optical fiber 45 is cured while passing through the ultraviolet curing device 24, and is wound on the winder (not shown) through the capstan 40. The tension of the optical fiber 45 is adjusted according to the rotational speed of the capstan 40, thereby limiting the diameter and output speed of the optical fiber 45.

On the other hand, the optical fiber twist device 50 provided between the curing device 24 and the capstan 40 twists the drawn optical fiber 45 periodically. At this time, the optical fiber 45 is twisted at the point that is melted and drawn from the optical fiber base material (10).

The optical fiber twist device 50 operates as follows. 4 to 7, the cam member 72 rotates as the driving source 71 is driven. As the cam member 72 rotates, the pivot member 75 is reciprocated about the hinge shaft 75a. As the pivot member 75 rotates, the pair of link members 77 and 78 reciprocate linearly in opposite directions along one axis, that is, the y axis.

That is, when the rotation member 75 is rotated in the counterclockwise direction, one link member 77 is moved in one direction, that is, -y direction, and the other link member 78 is moved in another direction, that is, y direction. Accordingly, the housing 55 is rotated by a predetermined angle in the counterclockwise direction. In conjunction with the rotation of the housing 55, the plurality of rollers 60 is rotated by a predetermined angle in the counterclockwise direction while contacting the optical fiber 45.

In addition, when the rotation member 75 is rotated in the clockwise direction, one link member 77 is moved in the y direction, the other link member 78 is moved in the -y direction, and the housing 55 is rotated by a predetermined angle in the clockwise direction. Is rotated as much. In conjunction with the rotation of the housing 55, the plurality of rollers 60 are rotated by a predetermined angle in the clockwise direction while contacting the optical fiber 45.

When employing the optical fiber twist device 50 according to the present invention provided as described above, the plurality of rollers that are interlocked with the reciprocating rotation of the housing 55 while the optical fiber 45 coming in a straight line is in close contact with the plurality of rollers 60. The optical fiber 45 can be twisted periodically by the reciprocating rotation of 60. In addition, since the position of the housing 55 is adjusted by the X-Y stage 80 so that the rotation axis of the optical fiber 45 and the housing 55 exactly coincide, no deviation occurs in the twisting of the optical fiber 45.

In the optical fiber extracting apparatus according to the present invention as described above, a plurality of rollers are rotatably installed in the housing so that the optical fiber maintains its original position on the path of the optical fiber to be drawn out, and the plurality of rollers are interlocked with the reciprocating rotation of the housing. The rollers of the reciprocating rotation adopt an optical fiber twisting device that twists the optical fiber periodically to twist the optical fiber periodically. Therefore, since the optical fiber twisted out of the drawing device and twisted periodically has a small average value of the polarization mode dispersion, the optical fiber produced by the fiber drawing device as described above can transmit the optical information signal with almost no distortion of the signal. have.

In addition, the optical fiber twisting device according to the present invention is installed on the optical fiber path that descends in a straight line to twist the optical fiber, and also adjust the position of the housing by the XY stage, so that the rotation axis of the housing and the path of the optical fiber coincide with the position of the optical fiber No deviation occurs in Therefore, when the optical fiber drawing device is used, not only the polarization mode dispersion characteristics but the drawn optical fiber and the center of the coating coincide, and the tension of the optical fiber is kept constant, thereby manufacturing an optical fiber having a constant outer diameter.

In addition, since the optical fiber drawing device as described above employs an optical fiber twisting device on a path of the optical fiber drawn down in a straight line, it is possible to manufacture the optically twisted optical fiber periodically while minimizing vibration during high speed drawing.

On the other hand, since the optical fiber is twisted by using a plurality of rollers when the optical fiber is drawn out, it is possible to prevent the breakage of the optical fiber due to stress concentration.

Claims (6)

A melting furnace for melting the optical fiber base material to pull out the optical fiber, a cooling device for cooling the optical fiber drawn out of the melting furnace to an appropriate temperature, a coating device for coating the cooled optical fiber, and curing for curing the coated optical fiber. In the optical fiber extracting device comprising a capstan for controlling the extraction speed of the optical fiber by adjusting the tension of the optical fiber according to the rotation thereof, and an optical fiber twist device installed between the curing device and the capstan to twist the optical fiber at a constant cycle , The optical fiber twist device, A base; A housing slidably installed in the base and having a through hole through which the optical fiber moved from the curing apparatus toward the capstan is formed; A plurality of rollers contacting the optical fiber passing through the through hole and rotatably installed in the housing; And rotating means for causing the optical fiber to be twisted by the rotation of the plurality of rollers interlocked with the rotation of the housing by rotating the housing by a predetermined angle. The method of claim 1, wherein the plurality of rollers, A plurality of support rollers for supporting the optical fiber passing through the through hole so as not to be released from its original position; And a plurality of pushing rollers disposed between the support rollers to be in close contact with the support rollers without slipping so as to be interlocked with the rotation of the housing to twist the optical fiber. The method of claim 2, wherein the support rollers are composed of first, second, third and fourth support rollers sequentially arranged, The first and third support rollers or the second and fourth support rollers are arranged side by side along one side of the optical fiber, the remaining two support rollers are arranged side by side along the other side orthogonal to one side of the optical fiber. Optical fiber drawing device. The method of claim 2, wherein the pushing roller consists of first and second pushing rollers arranged in sequence, One pushing roller of the first and second pushing rollers is disposed on one side of the optical fiber, the other pushing roller is disposed on the other side orthogonal to one side of the optical fiber. The method of claim 1, wherein the rotation means, A drive source installed in the base; A cam member installed on a rotation shaft of the drive source and driven by the drive source; A rotating member rotatably installed on the base, the rotating member being rotated about the hinge axis according to the rotation of the cam member; An elastic member installed on one side of the pivot member to elastically bias the pivot member toward the cam member; And a link member installed between the housing and the pivot member to allow the housing to reciprocate by a predetermined angle in accordance with the rotation of the pivot member. The optical fiber twist device according to any one of claims 1 to 5, And an X-Y stage for adjusting the position of the housing so that the rotating shaft of the housing coincides with the optical fiber penetrated by adjusting the base in the X-direction and the Y-direction.