Optical fiber manufacturing apparatus and optical fiber manufacturing method

Abstract

Provided is an optical fiber production apparatus equipped with a guide roller mechanism which is brought into contact with a specific groove to guide a running optical fiber. The guide roller mechanism is provided with: a plurality of guide roller main bodies (which are illustrated by an immediate-below roller 18, a pressing roller 18a, a twisting regulation roller 18b, and a guide roller 18c,18d) which are configured in a rotatable manner and guide a running optical fiber; and a guide roller rotational axis fixation mechanism which supports a rotational axis of each of at least two guide roller main bodies among the plurality of guide roller main bodies in a rotatable manner. The guide roller rotational axis fixation mechanism has: a position adjustment mechanism for adjusting the horizontal biaxial position of each rotational axis on a horizontal plane including the axis direction; and an angle adjustment mechanism for adjusting the inclination angle of each rotational axis.

Description

[Technical Field]

[0001] The present disclosure relates to an optical fiber manufacturing apparatus and an optical fiber manufacturing method.

[0002] This application claims priority to Japanese Application No. 2021-072767, filed on April 22, 2021, and incorporates by reference all of the contents of said Japanese application. [Background technology]

[0003] Optical fiber is manufactured by heating and melting the glass preform for optical fiber in a heating furnace and drawing it from below the furnace. The glass fiber drawn out of the heating furnace goes through a cooling process, a process of measuring the outer diameter, a process of coating with resin, etc. to become an optical fiber, and is transported while being guided by rollers directly below it and wound onto a bobbin. The glass fiber drawn from the heating furnace may have a slightly elliptical or distorted circular shape. For this reason, for example, Patent Document 1 discloses a structure in which an oscillating roller that oscillates around a predetermined vertical axis is provided downstream of the immediately below roller. By oscillating the oscillating roller, the optical fiber fed from the immediately below roller is twisted, making it possible to make the optical fiber closer to a perfect circle. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. 2000 / 044680 Summary of the Invention

[0005] An optical fiber manufacturing apparatus according to one embodiment of the present disclosure is an optical fiber manufacturing apparatus equipped with a guide roller mechanism that guides a running optical fiber by contacting it with a predetermined groove, wherein the guide roller mechanism is configured to be rotatable and includes a plurality of guide roller bodies that respectively guide the running optical fiber, and a guide roller rotation shaft fixing mechanism that rotatably supports the rotation shafts of at least two of the plurality of guide roller bodies, and the guide roller rotation shaft fixing mechanism has a position adjustment mechanism that adjusts the horizontal position of each of the rotation shafts in two horizontal planes including the axial direction, and an angle adjustment mechanism that adjusts the inclination angle of each of the rotation shafts.

[0006] An optical fiber manufacturing method according to one aspect of the present disclosure includes a guide roller mechanism to which a plurality of guide roller bodies are attached, each of which guides a traveling optical fiber, and a measuring device provided with a distance sensor disposed opposite the guide roller mechanism and measuring a distance from the guide roller bodies, and the method adjusts the mounting positions of the plurality of guide roller bodies relative to the guide roller mechanism, and includes the steps of: moving the distance sensor to face a predetermined measurement point provided on a side surface of a first guide roller body; measuring the distance from the predetermined measurement point provided on the side surface of the first guide roller body to a predetermined measurement reference surface provided on the measuring device with the distance sensor; moving the distance sensor to face a measurement point other than the predetermined measurement point provided on the side surface of the first guide roller body; measuring the distance from the other measurement point to the predetermined measurement reference surface with the distance sensor; and adjusting the mounting positions of the first guide roller bodies relative to the guide roller mechanism based on the results of these measurements. the distance sensor is moved to face a predetermined measurement point provided on the side of the second guide roller body that is located downstream of the first guide roller body; measuring the distance from the predetermined measurement point provided on the side of the second guide roller body to a predetermined measurement reference surface provided on the measuring instrument using the distance sensor; moving the distance sensor to face a measurement point other than the predetermined measurement point provided on the side of the second guide roller body; measuring the distance from the other measurement point provided on the side of the second guide roller body to the predetermined measurement reference surface using the distance sensor; and adjusting the mounting position of the second guide roller body based on these measurement results so that the side of the second guide roller body is parallel to the side of the first guide roller body. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a schematic diagram of an optical fiber manufacturing apparatus according to one embodiment of the present disclosure. [Figure 2] FIG. 2 is a configuration diagram of the guide roller mechanism and the measuring device. [Figure 3] FIG. 3 is a perspective view of the guide roller mechanism. [Figure 4] FIG. 4 is an operational flowchart including adjustment of the mounting position of the rotary shaft. [Figure 5A] FIG. 5A is a diagram illustrating distance measurement. [Figure 5B] FIG. 5B is a diagram illustrating the measurement points. DETAILED DESCRIPTION OF THE INVENTION

[0008] [Problem to be solved by this disclosure] The optical fiber is sent downstream while being guided by the guide roller bodies, such as the direct below roller. If the position and orientation of each guide roller body do not match the path line of the optical fiber, the optical fiber may ride up on the side of the groove of the guide roller body, damaging the surface of the optical fiber or twisting the optical fiber. For this reason, it is desirable to center the guide roller bodies with high precision.

[0009] The present disclosure has been made in consideration of the above-described circumstances, and aims to provide an optical fiber manufacturing apparatus and an optical fiber manufacturing method that are capable of centering guide roller bodies with high precision.

[0010] [Effects of this disclosure] According to the present disclosure, the guide roller bodies can be centered with high precision.

[0011] [Description of the embodiments of the present disclosure] First, the contents of the embodiments of the present disclosure will be listed and described. The optical fiber manufacturing apparatus according to the present disclosure is (1) an optical fiber manufacturing apparatus including a guide roller mechanism that guides a running optical fiber by contacting it with a predetermined groove, wherein the guide roller mechanism is configured to be rotatable and includes a plurality of guide roller bodies that respectively guide the running optical fiber, and a guide roller rotation shaft fixing mechanism that rotatably supports the rotation shafts of at least two of the plurality of guide roller bodies, and the guide roller rotation shaft fixing mechanism has a position adjustment mechanism that adjusts the horizontal position of each of the rotation shafts in two horizontal planes including the axial direction, and an angle adjustment mechanism that adjusts the inclination angle of each of the rotation shafts. The guide roller rotation shaft fixing mechanism supports the rotation shafts of all of the guide roller bodies and adjusts the two horizontal axis positions (also called translation positions) and tilt angles of each guide roller body, making it possible to manage the translation positions of each guide roller body, or to manage only the tilt of each guide roller while leaving the translation positions of each guide roller unchanged.This allows the guide roller bodies to be centered with high precision.

[0012] (2) In one aspect of the optical fiber manufacturing apparatus of the present disclosure, the guide roller rotating shaft fixing mechanism has an adjustment reference surface for adjusting the two horizontal axis positions of each of the rotating shafts and for adjusting the inclination angle of each of the rotating shafts. By using the adjustment reference plane, the horizontal two axis positions and tilt angles of each rotation axis can be easily adjusted. (3) In one aspect of the optical fiber manufacturing apparatus of the present disclosure, the plurality of guide roller bodies include a directly below roller configured to be rotatable below a predetermined furnace and to guide the optical fiber that is pulled out of the furnace and running in a vertical direction; a hold down roller configured to be rotatable downstream of the directly below roller and arranged on the opposite side of the optical fiber guided by the directly below roller to guide the optical fiber guided by the directly below roller; a twist adjustment roller configured to be rotatable downstream of the hold down roller and arranged on the opposite side of the optical fiber guided by the hold down roller to guide the optical fiber guided by the hold down roller; and a plurality of guide rollers configured to be rotatable downstream of the twist adjustment roller and each guide the optical fiber guided by the twist adjustment roller toward a predetermined capstan. By using the guide roller mechanism, even when there are multiple guide roller bodies, the horizontal two-axis positions and inclination angles of each rotation shaft can be easily adjusted. (4) In one aspect of the optical fiber manufacturing apparatus of the present disclosure, the predetermined furnace is a heating furnace that heats and melts a glass preform for an optical fiber. When the directly below roller guides the optical fiber that is pulled out of the heating furnace and runs vertically, misalignment of the directly below roller causes twisting of the optical fiber as it moves along the inner wall surface of the roller's groove. However, by using a guide roller mechanism, the directly below roller and the surrounding rollers can be aligned with high precision, preventing twisting of the optical fiber as it moves along the inner wall surface of the directly below roller's groove.

[0013] (5) A method of manufacturing an optical fiber according to the present disclosure includes a guide roller mechanism to which a plurality of guide roller bodies are attached, each of which guides a traveling optical fiber, and a measuring device provided with a distance sensor disposed opposite the guide roller mechanism to measure the distance from the guide roller bodies, and the method adjusts the attachment positions of the plurality of guide roller bodies relative to the guide roller mechanism, and includes the steps of: moving the distance sensor to face a predetermined measurement point provided on a side surface of a first guide roller body; measuring the distance from the predetermined measurement point provided on the side surface of the first guide roller body to a predetermined measurement reference surface provided on the measuring device with the distance sensor; moving the distance sensor to face a measurement point other than the predetermined measurement point provided on the side surface of the first guide roller body; measuring the distance from the other measurement point to the predetermined measurement reference surface with the distance sensor; and adjusting the attachment positions of the first guide roller body based on the results of these measurements. the distance sensor is moved so that it faces a predetermined measurement point provided on the side of a second guide roller body located downstream of the first guide roller body; measuring the distance from the predetermined measurement point provided on the side of the second guide roller body to a predetermined measurement reference surface provided on the measuring instrument with the distance sensor; moving the distance sensor so that it faces a measurement point other than the predetermined measurement point provided on the side of the second guide roller body; measuring the distance from the other measurement point provided on the side of the second guide roller body to the predetermined measurement reference surface with the distance sensor; and adjusting the mounting position of the second guide roller body based on these measurement results so that the side of the second guide roller body is parallel to the side of the first guide roller body. The distances at multiple points on the side of each guide roller body are measured and the mounting position of each guide roller body is adjusted, so that the guide roller bodies can be centered with high precision and twisting of the optical fiber caused by movement along the inner wall surface of the groove of each guide roller body can be prevented. (6) In one aspect of the method for producing an optical fiber of the present disclosure, the number of the second guide roller bodies is four or more. By adjusting the mounting position of each guide roller body so that the side of each guide roller body is parallel to the guide roller mechanism, the mounting position of each guide roller body can be easily adjusted even when there are four or more guide roller bodies.

[0014] [Details of the embodiments of the present disclosure] Specific examples of an optical fiber manufacturing apparatus and an optical fiber manufacturing method according to the present disclosure will be described below with reference to the accompanying drawings: Figure 1 is a schematic diagram of an optical fiber manufacturing apparatus according to one embodiment of the present disclosure. As shown in FIG. 1, an optical fiber manufacturing apparatus 10 includes, at its most upstream position, a heating furnace 11 for heating and softening a glass preform G for optical fiber.

[0015] The heating furnace 11 has a cylindrical furnace tube 12 inside which a glass base material G is supplied, a heating element 13 surrounding the furnace tube 12, and a gas supply unit 14 that supplies a purge gas into the furnace tube 12. The upper part of the glass preform G is held by a preform feeding unit F, and the glass preform G is fed into the furnace tube 12 using the preform feeding unit F. When the lower end portion of the glass preform G is heated by the heating element 13 and drawn downward, a glass fiber G1 that will become the central part of the optical fiber G2 is formed.

[0016] The optical fiber manufacturing apparatus 10 includes a cooling unit 15 downstream of the heating furnace 11. A cooling gas, for example, helium gas, is supplied to the cooling unit 15, and the glass fiber G1 drawn downward from the heating furnace 11 is cooled by the cooling unit 15. Note that the cooling unit 15 may be a cooling system using a cooling gas other than helium gas, as long as it can cool the glass fiber G1 without contacting it.

[0017] The optical fiber manufacturing apparatus 10 includes an outer diameter measuring unit 16 downstream of the cooling unit 15. The outer diameter measuring unit 16 is configured to be able to measure the outer diameter of the glass fiber G1 using, for example, laser light, and the cooled glass fiber G1 has its outer diameter measured by the outer diameter measuring unit 16 before being sent downward. Note that the outer diameter measuring unit 16 may be configured using a system other than a laser system as long as it can measure the outer diameter of the glass fiber G1 in a non-contact manner.

[0018] The optical fiber manufacturing apparatus 10 includes a coating unit 17 downstream of the outer diameter measurement unit 16. The glass fiber G1, whose outer diameter has been measured, is coated with, for example, a urethane acrylate resin, which is an ultraviolet-curable resin, and the urethane acrylate resin is cured by irradiating it with ultraviolet light. This results in an optical fiber G2 in which a resin layer is formed around the glass fiber G1.

[0019] The optical fiber manufacturing apparatus 10 includes a guide roller mechanism 50 downstream of the coating unit 17. The guide roller mechanism 50 includes, for example, a direct below roller 18, a pressure roller 18a, a twist adjustment roller 18b, and guide rollers 18c and 18d. The direct below roller 18, the pressure roller 18a, the twist adjustment roller 18b, and the guide rollers 18c and 18d are provided with grooves of a predetermined shape, such as a fiber running groove with a V-shaped cross section, and the optical fiber G2 is guided by coming into contact with the inner wall surface of this groove.

[0020] The direct below roller 18, pressure roller 18a, twist adjustment roller 18b, and guide rollers 18c and 18d correspond to the guide roller main body of the present disclosure. Of these, the direct below roller 18 corresponds to the first guide roller main body of the present disclosure, and the pressure roller 18a, twist adjustment roller 18b, and guide rollers 18c and 18d correspond to the second guide roller main body of the present disclosure. However, the second guide roller main body may consist of four or more rollers (for example, six rollers).

[0021] The directly below roller 18 is disposed directly below the heating furnace 11, and guides the optical fiber G2 that is pulled out from the heating furnace 11 and runs in the vertical direction. The hold down roller 18a is disposed downstream of the directly below roller 18, on the opposite side of the optical fiber G2 guided by the directly below roller 18, and holds down and guides the optical fiber G2 guided by the directly below roller 18. A swing roller 19 may be provided between the pressure roller 18a and the twist adjustment roller 18b. The swing roller 19 is configured to be swingable about a predetermined vertical axis. The swing roller 19 is configured to be rotatable downstream of the pressure roller 18a, and changes the running direction of the optical fiber G2 from the vertical direction to, for example, the horizontal direction.

[0022] The twist adjustment roller 18b is disposed, for example, downstream of the oscillating roller 19, on the opposite side (the same side as the directly below roller 18) across the optical fiber G2 guided by the pressure roller 18a, and guides the optical fiber G2 guided by the pressure roller 18a while restricting the twist of the optical fiber G2. The guide rollers 18c and 18d are downstream of the twist adjustment roller 18b, and each guide the optical fiber G2 guided by the twist adjustment roller 18b toward a predetermined capstan 20.

[0023] As shown in Fig. 2, the guide roller mechanism 50 has a guide roller rotation shaft fixing mechanism 52. As shown in Figs. 2 and 3, the guide roller rotation shaft fixing mechanism 52 has a fixing mechanism main body 53, a position adjustment mechanism 55, and an angle adjustment mechanism 56. The rotation shafts 51 of the direct below roller 18, the pressure roller 18a, the torsion adjustment roller 18b, and the guide rollers 18c and 18d are rotatably supported by arms 57 that are L-shaped in plan view.

[0024] In this embodiment, an example is described in which all of the rotation shafts 51 of the direct below roller 18, the pressure roller 18a, the torsion adjustment roller 18b, and the guide rollers 18c and 18d are supported by the arms 57 provided on the fixing mechanism main body 53, but the present disclosure is not limited to this example. For example, at least two of the rotation shafts 51 of the direct below roller 18, the pressure roller 18a, the torsion adjustment roller 18b, and the guide rollers 18c and 18d may be provided on the arms 57. Furthermore, the fixing mechanism main body 53 may be formed, for example, from a single metal plate, or may have a structure in which multiple metal plates are fixed together with bolts or the like.

[0025] 3, the position adjustment mechanism 55 is attached to the adjustment reference surface 54 of the fixing mechanism main body 53 via a support 58. The angle adjustment mechanism 56 is placed on this position adjustment mechanism 55. The arm 57 is attached to the angle adjustment mechanism 56. Furthermore, the position adjustment mechanism 55 and the angle adjustment mechanism 56 are configured using, for example, a plurality of adjustment screws, and the position and angle of the rotation shaft 51 are adjusted by changing the degree of fastening of each adjustment screw. The adjustment reference surface 54 of the fixing mechanism main body 53 is used as a reference when adjusting the two horizontal axis positions of the rotation shaft 51 and when adjusting the tilt angle. Note that the position adjustment mechanism 55 and the angle adjustment mechanism 56 may each include a stage instead of a plurality of adjustment screws. Specifically, the position adjustment mechanism 55 is configured, for example, by an XY stage that adjusts the horizontal two-axis position (also referred to as the translation position) of the rotation axis 51 on a horizontal plane having the vertical direction as the normal line, i.e., on a horizontal plane including the axial direction. On the other hand, the angle adjustment mechanism 56 is configured, for example, by a goniostage configured to be able to rotate the rotation axis 51 vertically, or a horizontal rotation stage configured to be able to rotate it horizontally.

[0026] On the other hand, a measuring device 60 is provided at a position opposite the guide roller mechanism 50. The measuring device 60 has a distance sensor 62, a moving mechanism 63, and a control unit 64. The distance sensor 62 is configured, for example, using a laser method or an IR (Infrared) method, and outputs the measurement results to the control unit 64. The measuring device 60 has a virtual measurement reference plane 61, which is used as a reference when measuring with the distance sensor 62. The moving mechanism 63 is configured to be able to move the distance sensor 62, for example, in a horizontal direction (X-axis direction shown in FIGS. 5A and 5B) or a vertical direction (Z-axis direction shown in FIGS. 5A and 5B) based on a drive signal from the control unit 64.

[0027] The control unit 64 is made up of a CPU, memory, etc., and loads various programs and data stored in, for example, a ROM into a RAM and executes the programs, thereby controlling the operation of the measuring device 60 based on the programs. In addition, when each rotation axis 51 is quantitatively adjusted using a position adjustment mechanism (e.g., XY stage) 55 and an angle adjustment mechanism (e.g., goniostage, horizontal rotation stage) 56, a control unit 59 may also be provided in the guide roller mechanism 50.

[0028] Returning to FIG. 1, the optical fiber G2 guided by the guide rollers 18c and 18d has its running direction changed by the guide roller 18d from the horizontal direction to, for example, an obliquely upward direction. The optical fiber manufacturing apparatus 10 further includes a capstan 20, a screening unit 21, and a dancer roller 22 downstream of the guide roller 18d. The optical fiber G2 is drawn by the capstan 20 at a predetermined speed, and while a predetermined tension is applied by the dancer roller 22, the optical fiber G2 is given a predetermined elongation strain by the screening unit 21, and then wound onto a bobbin B.

[0029] FIG. 4 is an operational flowchart including adjustment of the mounting position of the rotary shaft. As described above, it is assumed that a total of six rollers, namely, the direct below roller 18, the pressure roller 18a, the twist adjustment roller 18b, and the guide rollers 18c and 18d, are installed in the guide roller rotation shaft fixing mechanism 52. First, the distance sensor 62 is moved to adjust the installation position of the direct below roller 18.

[0030] 5A and 5B, for example, four measurement points X1, X2, Z1, and Z2 are provided on the side surface of the directly below roller 18. Measurement point X1 and measurement point X2 are each located on the X axis shown in the figure, and are equidistant from the center of the rotation shaft 51. Measurement point Z1 and measurement point Z2 are each located on the Z axis shown in the figure, and are each equidistant from the center of the rotation shaft 51. Then, the distance sensor 62 is moved so that it faces a predetermined measurement point Z2 provided on the side surface of the directly below roller 18 (step S10 in FIG. 4).

[0031] Next, the distance sensor 62 measures the distance from the measurement point Z2 to the measurement reference surface 61 of the measuring device 60 (step S11). The measurement result is stored in the memory of the control unit 64. Next, the process proceeds to step S12, where the control unit 64 determines whether or not measurements have been taken at a total of four measurement points X1, X2, Z1, and Z2 on the directly below roller 18. If measurements have not been taken at all measurement points (NO in step S12), the process returns to step S10, where the distance sensor 62 is moved along the Z axis to face, for example, a measurement point Z1 different from measurement point Z2.

[0032] Then, the distance sensor 62 measures the distance from this measurement point Z1 to the measurement reference surface 61 (step S11), and stores the measurement result. Next, since measurements of all measurement points have not been completed (NO in step S12), distance sensor 62 is moved along the Z axis and X axis to face, for example, measurement point X1, which is different from measurement points Z1 and Z2 (step S10). Distance sensor 62 measures the distance from measurement point X1 to measurement reference surface 61 (step S11) and also stores this measurement result.

[0033] After that, since measurements of all measurement points have not been completed (NO in step S12), the process returns to step S10, and distance sensor 62 is moved along the X axis to face, for example, measurement point X2, which is different from measurement point X1. Distance sensor 62 measures the distance from measurement point X2 to measurement reference surface 61 (step S11), and also stores this measurement result. If the measurement of all measurement points on the immediately below roller 18 has been completed (YES in step S12), the process proceeds to step S13.

[0034] In this step S13, based on the measurement results of measurement points X1, X2, Z1, and Z2, the position adjustment mechanism 55 and the angle adjustment mechanism 56 adjust the mounting position of the rotation axis 51 of the direct below roller 18 so that the side of the direct below roller 18 is parallel to the adjustment reference surface 54 of the fixing mechanism main body 53 (step S13). Next, the process proceeds to step S14, where the control unit 64 determines whether measurements have been taken of the direct below roller 18, the pressure roller 18a, the twist adjustment roller 18b, and the guide rollers 18c and 18d. If measurements of the pressure roller 18a, the twist adjustment roller 18b, and the guide rollers 18c and 18d have not been completed (NO in step S14), the process returns to step S10, and the distance sensor 62 is moved to adjust the attachment position of the pressure roller 18a.

[0035] For example, four measurement points X1, X2, Z1, and Z2 are provided on the side surfaces of the pressure roller 18a, the twist adjustment roller 18b, and the guide rollers 18c and 18d (FIGS. 5A and 5B). Then, the distance sensor 62 is moved to face, for example, the measurement point Z2 of the pressure roller 18a (step S10 in FIG. 4), and the distance from this measurement point Z2 to the measurement reference surface 61 is measured (step S11) and stored.

[0036] Thereafter, the movement and measurement of the distance sensor 62 is repeated (NO in step S12, step S10, step S11), and when measurements of all measurement points on the pressure roller 18a have been completed (YES in step S12), the process proceeds to step S13, where the position adjustment mechanism 55 and angle adjustment mechanism 56 adjust the mounting position of the rotation axis 51 of the pressure roller 18a based on the measurement results of measurement points X1, X2, Z1, and Z2 so that the side of the pressure roller 18a is parallel to the side of the roller 18 directly below (and thus the adjustment reference surface 54).

[0037] Next, in order to adjust the mounting position of the twist adjustment roller 18b (NO in step S14), the distance sensor 62 is moved, for example, to face the measurement point Z2 of the twist adjustment roller 18b (step S10), and the distance from this measurement point Z2 to the measurement reference surface 61 is measured (step S11) and stored. Movement and measurement of distance sensor 62 are repeated (NO in step S12, steps S10, S11) until measurements of all measurement points on twist adjustment roller 18b are completed (YES in step S12). When measurements of all measurement points are completed (YES in step S12), position adjustment mechanism 55 and angle adjustment mechanism 56 adjust the mounting position of rotation axis 51 of twist adjustment roller 18b based on the measurement results of measurement points X1, X2, Z1, and Z2 so that the side of twist adjustment roller 18b is parallel to the side of the roller 18 directly below (step S13).

[0038] Thereafter, the movement and measurement of the distance sensor 62 is repeated for the guide rollers 18c and 18d in the same manner as described above (NO in step S12, step S10, step S11), and based on the measurement results of measurement points X1, X2, Z1, and Z2, the position adjustment mechanism 55 and the angle adjustment mechanism 56 adjust the mounting positions of the rotation axes 51 of the guide rollers 18c and 18d so that each side of the guide rollers 18c and 18d is parallel to the side of the roller 18 directly below (step S13). Then, when the measurements of the immediately below roller 18, the pressure roller 18a, the twist adjusting roller 18b, and the guide rollers 18c and 18d are completed (YES in step S14), the process exits from the series of routines.

[0039] In this way, the distances are measured at a total of four locations on each side of the directly below roller 18, the pressure roller 18a, the twist adjustment roller 18b, and the guide rollers 18c and 18d, and the mounting positions of the directly below roller 18, the pressure roller 18a, the twist adjustment roller 18b, and the guide rollers 18c and 18d are adjusted based on the measured distances. This allows the directly below roller 18, the pressure roller 18a, the twist adjustment roller 18b, and the guide rollers 18c and 18d to be aligned with high accuracy. More specifically, the directly below rollers 18 and the like, which were previously positioned at intervals of, for example, 29.5 mm to 30.2 mm, can now be positioned at high accuracy of 29.95 mm to 30.03 mm. As a result, twisting of the optical fiber caused by movement along the inner wall surfaces of the grooves of the directly below roller 18, the pressure roller 18a, the twist adjustment roller 18b, and the guide rollers 18c and 18d, can be prevented.

[0040] The embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive. The scope of the present disclosure is defined by the scope of the claims, not by the meaning described above, and is intended to include all modifications within the meaning and scope equivalent to the scope of the claims. For example, in the flowchart of Figure 4, after step S12, a step for determining the accuracy of roller centering may be provided, and if the predetermined accuracy is met, step S13 may be skipped and the process may proceed to step S14; if the predetermined accuracy is not met, the process may proceed to step S13 and then to step S10 again, and adjustment of the mounting position and measurement may be repeated until the predetermined accuracy is met. [Explanation of symbols]

[0041] 10...optical fiber manufacturing apparatus, 11...heating furnace, 12...furnace tube, 13...heating element, 14...gas supply unit, 15...cooling unit, 16...outer diameter measurement unit, 17...coating unit, 18...directly below roller (guide roller body), 18a...pressure roller (guide roller body), 18b...twist adjustment roller (guide roller body), 18c, 18d...guide roller (guide roller body), 19...oscillating roller, 20...capstan, 21...screening unit, 22...dan Sarolla, 50...guide roller mechanism, 51...rotating shaft, 52...guide roller rotating shaft fixing mechanism, 53...fixing mechanism body, 54...adjustment reference surface, 55...position adjustment mechanism, 56...angle adjustment mechanism, 57...arm, 58...support, 59...control unit, 60...measuring equipment, 61...measurement reference surface, 62...distance sensor, 63...movement mechanism, 64...control unit, F...base material feed unit, G...glass base material, G1...glass fiber, G2...optical fiber, B...bobbin, X1, X2, Z1, Z2...measurement point.

Claims

1. An optical fiber manufacturing apparatus including a guide roller mechanism that guides a traveling optical fiber by contacting the guide roller with a predetermined groove, the guide roller mechanism is configured to be rotatable and includes a plurality of guide roller bodies each guiding a traveling optical fiber, and a guide roller rotation shaft fixing mechanism that rotatably supports the rotation shafts of at least two of the plurality of guide roller bodies, An optical fiber manufacturing apparatus, wherein the guide roller rotating shaft fixing mechanism has a position adjustment mechanism that adjusts the two horizontal axis positions of each of the rotating shafts in a horizontal plane including the axial direction, and an angle adjustment mechanism that adjusts the inclination angle of each of the rotating shafts.

2. 2. The optical fiber manufacturing apparatus according to claim 1, wherein the guide roller rotating shaft fixing mechanism has an adjustment reference surface for adjusting the two horizontal axis positions of each of the rotating shafts and for adjusting the tilt angle of each of the rotating shafts.

3. The plurality of guide roller bodies include: a roller configured to be rotatable below a predetermined furnace and configured to guide the optical fiber drawn out of the furnace and running in a vertical direction; a pressing roller configured to be rotatable downstream of the immediately below roller, and disposed on the opposite side of the optical fiber guided by the immediately below roller, for guiding the optical fiber guided by the immediately below roller; a twist adjustment roller configured to be rotatable downstream of the pressure roller, and disposed on the opposite side of the optical fiber guided by the pressure roller to guide the optical fiber guided by the pressure roller; a plurality of guide rollers configured to be rotatable downstream of the twist adjustment roller, each of which guides the optical fiber guided by the twist adjustment roller toward a predetermined capstan; 3. The optical fiber manufacturing apparatus according to claim 1, further comprising:

4. 4. The optical fiber manufacturing apparatus according to claim 3, wherein the predetermined furnace is a heating furnace for heating and melting a glass preform for an optical fiber.

5. A method for manufacturing an optical fiber, comprising: a guide roller mechanism to which a plurality of guide roller bodies are attached, each of which guides a traveling optical fiber; and a measuring device provided with a distance sensor disposed opposite the guide roller mechanism and measuring the distance to the guide roller body, the method comprising: adjusting the attachment positions of the plurality of guide roller bodies relative to the guide roller mechanism, a step of moving the distance sensor to face a predetermined measurement point provided on a side surface of the first guide roller body; measuring a distance from a predetermined measurement point provided on a side surface of the first guide roller body to a predetermined measurement reference surface provided on the measuring device by the distance sensor; moving the distance sensor to face a measurement point other than the predetermined measurement point provided on a side surface of the first guide roller body; measuring a distance from the other measurement point to the predetermined measurement reference plane with the distance sensor; Based on these measurement results, adjusting the mounting position of the first guide roller body so that the side surface of the first guide roller body is parallel to the predetermined measurement reference plane; a step of moving the distance sensor to face a predetermined measurement point provided on a side surface of a second guide roller body located downstream of the first guide roller body; measuring a distance from a predetermined measurement point provided on a side surface of the second guide roller body to a predetermined measurement reference surface provided on the measuring device by the distance sensor; moving the distance sensor to face a measurement point other than the predetermined measurement point provided on a side surface of the second guide roller body; measuring a distance from the other measurement point provided on a side surface of the second guide roller body to the predetermined measurement reference surface with the distance sensor; Based on these measurement results, adjusting the mounting position of the second guide roller body so that the side surface of the second guide roller body is parallel to the side surface of the first guide roller body; A method for manufacturing an optical fiber, comprising:

6. 6. The method for producing an optical fiber according to claim 5, wherein the number of second guide roller bodies is four or more.

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