JP2011085718A - Apparatus and method for forming optical transmission medium, and method of manufacturing optical transmission medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical transmission medium forming apparatus, in which cracks are hardly caused in an optical transmission medium, and desired radius of curvature is accurately obtained when part of the optical transmission medium bridged in a predetermined space is heated from above at non-contact and bent. <P>SOLUTION: The optical transmission medium forming apparatus includes: a non-contact heating means 16 which heats at non-contact part of the optical transmission medium f bridged in the predetermined space; bending fixtures 12, 14 for applying force on the optical transmission medium f for bending; and a propping-up member 17 which is made to contact with the bottom of the heated part of the optical transmission medium f by the non-contact heating means 16. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an optical transmission medium molding apparatus that bends an optical transmission medium while heating a part of the optical transmission medium spanned in a predetermined space from above without contact, and optical transmission performed by the optical transmission medium molding apparatus. The present invention relates to a medium forming method and an optical transmission medium manufacturing method.

  For example, techniques described in Patent Document 1 and Non-Patent Document 1 are known as techniques for forming an optical transmission medium such as an optical fiber.

  Patent Document 1 describes a technique of bending a optical fiber at a predetermined radius by heating a part of the optical fiber by using arc discharge in a technique for bending an optical fiber.

  Non-Patent Document 1 discloses a technique for bending an optical fiber by applying the optical fiber to a cylindrical ceramic heater.

JP 2005-292718 A

Masahito Morimoto, “R = 1 mm 90-degree bending multimode fiber 2—examination of bending loss by BPM simulation”, IEICE technical report, IEICE, August 2008, IEICE Tech. 108 no. 193, p115-119

  However, the technique described in Patent Document 1 does not take into consideration that the bending of the optical fiber is performed with high productivity. In bending the optical fiber, the technique for bending the optical fiber to a desired radius of curvature is used. No measures for improving accuracy are taken into consideration.

  In the technique of Non-Patent Document 1, since the high-temperature ceramic heater is in contact with the optical fiber, a fine crack is likely to occur in the portion of the optical fiber that is in contact with the ceramic heater, and the optical fiber may be easily broken.

  SUMMARY OF THE INVENTION In view of the above circumstances, the present invention is an optical transmission medium molding apparatus, an optical transmission medium molding method, and an optical transmission medium manufacturing method, which are less likely to crack in an optical transmission medium and have improved accuracy for bending to a desired radius of curvature. The purpose is to provide.

(1) The optical transmission medium forming apparatus of the present invention that solves the above-described object includes a non-contact heating means that heats a part of the optical transmission medium spanned over a predetermined space in a non-contact manner,
A bending jig for bending the optical transmission medium by applying a force;
The optical transmission medium includes a lower support member that comes into contact with a portion that is heated by the non-contact heating means from below.

  According to the optical transmission medium forming apparatus of the present invention, since the optical transmission medium is heated in a non-contact manner by the non-contact heating means, the optical transmission medium is hardly cracked. In addition, since the portion of the optical transmission medium that is heated by the non-contact heating means is supported by the support member, for example, the portion can be prevented from bending downward due to the weight of the optical transmission medium. The accuracy for bending to the radius of curvature is improved.

  Here, the optical transmission medium bent by the bending jig may be provided with delivery means for feeding out in the longitudinal direction of the optical transmission medium.

  The delivery speed of the optical transmission medium by this delivery means is a speed according to the rotational speed of the bending jig.

  (2) In the optical transmission medium forming apparatus of the present invention, the rotating jig may rotate about the vicinity of the non-contact heating means.

  (3) In the optical transmission medium shaping | molding apparatus of this invention, it is preferable to provide the tension | tensile_strength provision means which provides tension | tensile_strength further to the optical transmission medium bent with the said bending jig | tool.

  By applying tension to the optical transmission medium, the optical transmission medium can be bent tightly, and the accuracy for bending to a desired radius of curvature is further improved.

  (4) In the optical transmission medium forming apparatus of the present invention, an aspect in which the support member has a cylindrical peripheral surface having a rotation axis orthogonal to the longitudinal direction of the optical transmission medium is also preferable.

  According to this aspect, the optical transmission medium is bent along the peripheral surface, and the accuracy for bending to a desired curvature radius is further improved. Further, by rotating, only a part of the peripheral surface is not continuously heated, and the temperature rise is suppressed locally, and the portion of the optical transmission medium in contact with the peripheral surface is prevented. Small cracks are less likely to occur.

  In addition, what has the said cylindrical surrounding surface may be a cylindrical body or a cylindrical body (hereinafter the same). Further, the one having the cylindrical peripheral surface may be rotationally driven by itself, and in the case of rotationally driving by itself, the rotational speed is a speed corresponding to the rotational speed of the bending jig. It is preferable that

  Here, the lower support member may be one in which the rotation axis coincides with the rotation center of the bending jig.

(5) In the optical transmission medium molding apparatus of the present invention, the optical transmission medium molding apparatus holds the optical transmission medium bent by the bending jig movably in the longitudinal direction of the optical transmission medium,
The lower support member may have a cylindrical peripheral surface that rotates around the rotation axis following the movement of the optical transmission medium bent by the bending jig in the longitudinal direction. .

  By doing so, it becomes unnecessary to control the sending speed of the optical transmission medium in the longitudinal direction and the rotating speed of the cylindrical peripheral surface in synchronization with the rotation of the bending jig, and the cost of the entire apparatus is increased. Can be suppressed. In addition, the support member in contact with the optical transmission medium rotates following the movement of the optical transmission medium, whereby friction between the optical transmission medium and the support member is eliminated, and cracks are less likely to occur in the optical transmission medium.

  (6) In the optical transmission medium forming apparatus of the present invention, the support member may be an insulator.

  When the support member is an insulator, the optical transmission medium can be uniformly heated in the width direction orthogonal to the longitudinal direction. However, the lower support member is not limited to an insulator but may be a conductor.

  (7) In the optical transmission medium forming apparatus of the present invention, the non-contact heating means may be an arc discharge electrode.

  (8) The optical transmission medium forming apparatus of the present invention may further include a height adjusting unit that adjusts the height of the optical transmission medium and the non-contact heating unit.

(9) An optical transmission medium molding method of the present invention that solves the above-mentioned object is an optical transmission medium molding method for bending an optical transmission medium using non-contact heating means,
A set process of linking the optical transmission medium to a predetermined space;
A bending process of applying a force to the optical transmission medium while bending a part of the optical transmission medium spanned in a predetermined space by a non-contact heating means,
The bending process is a process performed in a state where a part of the optical transmission medium heated by the non-contact heating means is supported from below.

  According to the optical transmission medium forming method of the present invention, it is carried out in the optical transmission medium forming apparatus of the present invention, and the optical transmission medium is hardly cracked, and the accuracy for bending to a desired radius of curvature is improved.

  (10) In the optical transmission medium forming method of the present invention, the bending process may be a process of bending the optical transmission medium using a bending jig capable of adjusting the angular velocity.

  (11) In the optical transmission medium forming method of the present invention, the bending process is preferably a process performed while applying tension to the optical transmission medium.

  (12) In the optical transmission medium forming method of the present invention, the bending step is a step of using the support member having a cylindrical peripheral surface having a rotation axis orthogonal to the longitudinal direction of the optical transmission medium. It is also preferable.

  (13) In the optical transmission medium forming method of the present invention, in the bending process, the optical transmission medium is used as the support member in a state where the transmission medium is held movably in the longitudinal direction of the optical transmission medium. It may be a step of bending using a cylindrical peripheral surface that rotates around the rotation axis following the movement in the longitudinal direction.

  (14) In the optical transmission medium forming method of the present invention, the bending step may be a step using an insulator as the support member.

  (15) In the optical transmission medium forming method of the present invention, the bending step may be a step of bending the optical transmission medium using a bending jig that rotates around the vicinity of the non-contact heating means. .

  (16) In the optical transmission medium forming method of the present invention, the bending process may be a process of bending the optical transmission medium by 90 degrees.

  (17) In the optical transmission medium forming method of the present invention, the bending step may be a step using an arc discharge electrode as the non-contact heating means.

  (18) In the optical transmission medium forming method of the present invention, the setting step may be a step of bridging a glass optical fiber as the optical transmission medium in a predetermined space.

  (19) In the optical transmission medium forming method of the present invention, the setting step may be a step of spanning an optical fiber structure composed of a plurality of optical fibers as the optical transmission medium in a predetermined space.

  (20) The optical transmission medium forming method of the present invention may be a method of bending a plurality of locations of the optical transmission medium in order.

  (21) An optical transmission medium manufacturing method of the present invention that solves the above-mentioned object is to manufacture a bent optical transmission medium using the optical transmission medium forming method according to any one of (9) to (20) above. It is characterized by.

  According to the present invention, there are provided an optical transmission medium molding apparatus, an optical transmission medium molding method, and an optical transmission medium manufacturing method that are less likely to cause cracks in the optical transmission medium and have improved accuracy for bending to a desired radius of curvature. can do.

It is a side view of the optical transmission medium bending apparatus which is one Embodiment of the optical transmission medium shaping | molding apparatus of this invention. It is the top view which looked at the optical transmission medium bending apparatus shown in FIG. 1 from the top. It is a figure when the front end side is seen from the rear end side rather than the height adjustment stage 15 of the optical transmission medium bending processing apparatus shown in FIG. FIG. 3 is a diagram schematically showing an optical fiber heated by a pair of arc discharge electrodes 16. It is a figure which shows a mode that the optical fiber fixing arm 14 of the horizontal state was rotated 30 degree | times toward the downward direction. It is a figure which shows a mode that the optical fiber fixed arm 14 of the horizontal state was rotated 60 degree | times toward the downward direction. It is a figure which shows a mode that the optical fiber fixing arm 14 of the horizontal state was rotated 90 degree | times toward the downward direction. It is a figure which shows the modification of the optical transmission medium bending apparatus 10 shown in FIG.

  Hereinafter, an optical transmission medium bending apparatus which is an embodiment of an optical transmission medium forming apparatus of the present invention will be described with reference to the drawings, and an optical transmission medium bending method using the optical transmission medium bending apparatus will be described. To do. The optical transmission medium bending method described here corresponds to an embodiment of the optical transmission medium forming method of the present invention, and includes a setting step and a bending step.

  FIG. 1 is a side view of an optical transmission medium bending apparatus which is an embodiment of an optical transmission medium forming apparatus of the present invention, and FIG. 2 is a plan view of the optical transmission medium bending apparatus shown in FIG. is there.

  An optical transmission medium bending apparatus 10 shown in FIG. 1 is an apparatus that bends a tape core wire F extending about several meters by 90 degrees. The tape core F includes a plurality of glass optical fibers f arranged at equal intervals in the width direction (direction perpendicular to the paper surface in FIG. 1) perpendicular to the extending direction (left-right direction in FIG. 1). A single optical fiber structure, which corresponds to an example of an optical transmission medium according to the present invention. The optical transmission medium bending apparatus 10 is an apparatus that can bend a plurality of optical fibers f at a time. The optical fiber to be bent may be made of any material such as glass and plastic, and can be appropriately selected depending on the application. However, an optical fiber made of glass is preferable in order to keep the bend accurately. Moreover, there is no restriction | limiting in the number of the optical fibers processed at once, A single core optical fiber may be sufficient.

  The optical transmission medium bending apparatus 10 shown in FIG. 1 includes an L-shaped bracket 11, a rotary stage 12, a U-shaped bracket 13, an optical fiber fixing arm 14, and a height adjustment stage 15. The L-shaped bracket 11 has a pedestal part 111 and a standing part 112. The rotary stage 12 is rotatably attached to the standing portion 112. The rotary stage 12 can be rotated by a motor (not shown) to adjust the angular velocity. The optical fiber fixing arm 14 rotates together with the rotary stage 12. The optical fiber fixing arm 14 is provided with an optical fiber tip side mounting portion 140. The fiber fixing arm 14 shown in FIG. 1 is in a horizontal state. The rotary stage 12 and the optical fiber fixing arm 14 may be provided integrally. A height adjustment stage 15 is fixed to the pedestal 111 of the L-shaped bracket 11. An optical fiber holding jig 151 is horizontally provided on the height adjustment stage 15.

  The tape core F is set in the optical transmission medium bending apparatus 10 in a state where the coating F1 is removed from the tip over a predetermined length (for example, refer to an example described later). Alternatively, the coating F1 may be left on the front end portion Ft, and the rear end side of the front end portion Ft may be set on the optical transmission medium bending apparatus 10 with the coating F1 removed over a predetermined length. The portion of the tape core wire F from which the coating F1 is removed has the cladding F2 exposed, but the rear end side is coated, so that the optical fibers f are also arranged at equal intervals in the width direction. It is out.

  As shown in FIG. 1, the optical fiber tip side mounting portion 140 of the optical fiber fixing arm 14 and the optical fiber holding jig 151 are arranged with a space therebetween, and the tape core wire F is on the optical fiber tip side. It is bridged in a predetermined space between the placing part 140 and the optical fiber holding jig 151. That is, the front end side of the tape core wire F is placed on the optical fiber front end side mounting portion 140 of the optical fiber fixing arm 14, and the rear end side of the tape core wire F is held by the optical fiber holding jig 151. The front end portion Ft of the tape core wire F is supported from below by the optical fiber front end side mounting portion 140, and the linearity of the tape core wire F is maintained.

  1 and 2, the left side of the figure is the leading end side of the tape core wire F, and the right side of the figure is the trailing end side of the tape core wire F. Although not shown, the tape core wire F further continues to the rear end side. Also in the optical transmission medium bending apparatus 10, the front end side of the tape core F set in the optical transmission medium bending apparatus 10 is referred to as the front end side of the apparatus, and the rear end side of the tape core F is the rear of the apparatus. Sometimes called end side. Moreover, the left-right direction of a figure may be called a longitudinal direction.

  The optical fiber distal end mounting portion 140 of the optical fiber fixing arm 14 is provided with a fixed plate 141 on the distal end side, and the tape spanned between the optical fiber fixing arm 14 and the optical fiber holding jig 151. The distal end side of the core wire F is pressed against the optical fiber distal end side mounting portion 140 by the fixing plate 141, and the tape core wire F is fixed so as not to move in the longitudinal direction. Note that the tip of the tape core wire F protrudes from the fixed plate 141. As described above, the tape core F is stretched over the predetermined space, and the front end of the tape core F is placed on the front end side of the optical fiber by the fixing plate 141 so that the tape core F cannot move in the longitudinal direction. While fixing to the part 140, the rear end side of the tape core wire F is placed on the optical fiber holding jig 151 (setting step).

  In addition, a U-shaped bracket 13 is attached to the upper end portion of the standing portion 112 of the L-shaped bracket 11.

  Furthermore, the optical transmission medium bending apparatus 10 includes a pair of arc discharge electrodes 16 and a ceramic shaft 17.

  Here, the description will be continued with reference to FIG. 3 together with FIGS.

  FIG. 3 is a view of the optical transmission medium bending apparatus shown in FIG. 1 when the front end side is viewed from the rear end side with respect to the height adjustment stage 15. In FIG. 3, the horizontal direction in the figure is the width direction of the tape core F.

  The pair of arc discharge electrodes 16 are provided on the vertical portion 131 of the U-shaped bracket 13 so as to face each other with a gap in the width direction. The pair of arc electrodes 16 is disposed at a position spaced upward from the tape core F spanned between the optical fiber tip side mounting portion 140 and the optical fiber holding jig 151. Between the pair of arc discharge electrodes 16, arc discharge is generated, and a portion of the tape core wire F between the optical fiber tip side mounting portion 140 and the optical fiber holding jig 151, that is, the cladding F <b> 2 is exposed. Then, the optical fibers f arranged in the width direction are heated in a non-contact manner. There is no risk of scratching the optical fiber by heating in a non-contact manner. The pair of arc discharge electrodes 16 corresponds to an example of the non-contact heating means referred to in the present invention.

  FIG. 4 is a diagram schematically showing an optical fiber heated by a pair of arc discharge electrodes 16. In FIG. 4, the horizontal direction in the figure is the width direction of the tape core F.

  The ceramic shaft 17 is an insulating cylindrical body having a rotation axis that coincides with the rotation center of the rotary stage 12 and has excellent heat resistance. The ceramic shaft 17 may be a cylindrical body. The rotation shaft of the ceramic shaft 17 is orthogonal to the longitudinal direction, and as shown in FIGS. 2 and 3, the shaft is rotatably rotatable at the rear end portion of the optical fiber front end mounting portion 140 in the optical fiber fixing arm 14. It is supported. Further, as shown in FIGS. 3 and 4, the peripheral surface 171 of the ceramic shaft 17 is in contact with the portion heated by the pair of arc discharge electrodes 16 of each of the optical fibers f aligned in the width direction from below. Support the part from below. The temperature distribution of the arc discharge generated between the pair of arc discharge electrodes 16 is such that the center between the pair of arc discharge electrodes 16 is a high temperature region, the periphery of the high temperature region is an intermediate temperature region, and the periphery of the intermediate temperature region is a low temperature region. Become. That is, the arc discharge temperature distribution is concentric. The temperature range suitable for bending the optical fiber f is an intermediate temperature range, the temperature is too high in the high temperature range to damage the optical fiber, and the temperature is too low in the low temperature range to make it difficult to bend the optical fiber f. . When trying to heat a plurality of optical fibers f arranged in the width direction at once, some of the optical fibers f at the center in the width direction are in the middle temperature range, but the optical fibers f on both sides in the width direction are in the low temperature range. It becomes difficult to bend the optical fibers f on both sides in the width direction. It is also possible to arrange a plurality of optical fibers f arranged in the width direction so as to cross the center between the pair of arc discharge electrodes 16, but in this case, an optical fiber f that enters a high temperature region is generated. And the optical fiber f is damaged. Therefore, in this embodiment, an insulator (ceramic shaft 17) is provided below the pair of arc discharge electrodes 16. As shown in FIG. 4, the insulator (ceramic shaft 17) is positioned in the vicinity between the pair of arc discharge electrodes 16, and the arc discharge A generated between the pair of arc discharge electrodes 16 is the insulator (ceramic shaft 17). The temperature distribution of the arc discharge does not become concentric. Due to this distortion, the lower part of the intermediate temperature region becomes substantially horizontal, and all of the plurality of optical fibers f arranged in the width direction can be put in the intermediate temperature region. The length a / the distance b between the pair of arc discharge electrodes 16 from the optical fiber at one end in the width direction to the optical fiber at the other end in the width direction is preferably 0.5 or more and 0.95 or less, more preferably 0. 5 or more and 0.9 or less.

  A conductor, not an insulator, may be provided below the pair of arc discharge electrodes 16. By providing the conductor, the arc discharge generated between the pair of arc discharge electrodes 16 is attracted and distorted by the conductor, and the temperature distribution of the arc discharge does not become concentric. Even with this distortion, the lower part of the intermediate temperature region becomes substantially horizontal, and all of the plurality of optical fibers arranged in the width direction can be placed in the intermediate temperature region. Moreover, you may provide the thing of the same electrical characteristic as the electrical characteristic body provided below on between between a pair of arc discharge electrodes 16. FIG. For example, when an insulator is provided between the electrodes, the insulator may also be provided between the electrodes. In this case, it is necessary to adjust the distance between the electrodes and the insulator provided above and below so as not to cause a current shortage.

  Next, a bending process in the optical transmission medium bending method will be described.

  In the bending process, each optical fiber f is bent while the optical fibers f are heated in a non-contact manner by arc discharge generated between the pair of arc discharge electrodes 16. A peripheral surface 171 of the ceramic shaft 17 is in contact with a part of the tape core wire F heated by the pair of arc discharge electrodes 16 (hereinafter referred to as a heating part of each optical fiber f) from below, and each optical fiber f The heating portion is supported by the ceramic shaft 17 from below. In this state, by rotating the rotary stage 12, the optical fiber fixing arm 14 to which the front end side of the tape core wire F is fixed is rotated counterclockwise. That is, the fixed plate 141 rotates downward with the vicinity of the pair of arc discharge electrodes 16 as the center of rotation, and rotates the front end side of the tape core wire F downward. In other words, the peripheral surface 171 of the ceramic shaft 17 rotates downward around the portion in contact with the tape core F (rotation center of the rotary stage 12) as the rotation center, and the tip end of the tape core F is downward. Rotate toward. Therefore, the rotary stage 12 and the optical fiber fixing arm 14 as rotating means correspond to an example of a bending jig according to the present invention, and the ceramic shaft 17 corresponds to an example of a support member according to the present invention. The optical fiber f is continuously heated in a certain range, and a minute bending process is continuously performed to form a bent portion.

  FIG. 5 is a view showing a state in which the optical fiber fixing arm 14 in the horizontal state is rotated downward by 30 degrees, and FIG. 6 is a state in which the optical fiber fixing arm 14 in the horizontal state is rotated downward by 60 degrees. FIG. 7 is a diagram illustrating a state in which the optical fiber fixing arm 14 in the horizontal state is rotated 90 degrees downward.

  As shown in FIGS. 5 to 7, the heated portion of each optical fiber f is bent along the peripheral surface 171 of the ceramic shaft 17, and all the optical fibers f arranged in the width direction are bent with the same radius of curvature. It is done. Therefore, by setting the ceramic shaft 17 to a peripheral surface having a curvature radius for obtaining a desired curvature radius in consideration of the diameter of the optical fiber f, all the optical fibers f aligned in the width direction are provided. Is improved to bend to a desired radius of curvature.

  Moreover, when the tape core wire F is bent, the tape core wire F is pulled toward the tip side. The optical fiber holding jig 151 provided on the height adjustment stage 15 is for holding the rear end side of the tape core wire F so that the tape core wire F can move to the front end side, and is subjected to bending processing. The tape core wire F is allowed to move toward the tip side. The optical fiber holding jig 151 is movable on the height adjustment stage 15 toward the front end side of the tape core wire F. In FIGS. 5 to 7, the optical fiber holding jig 151 is shown in FIG. 15 shows a state in which it gradually moves to the tip side. Thus, the ceramic shaft 17 rotates following the movement of the tape core wire F toward the tip side. As described above, in this embodiment, it is not necessary to control the feed speed of the tape core wire F to the front end side and the rotation speed of the ceramic shaft 17 in synchronization with the rotation of the rotary stage 12, and the cost of the entire apparatus is reduced. You can suppress the up. Note that the rotation of the rotary stage 12 and the rotation of the ceramic shaft 17 may be controlled separately. In this case, it is preferable that the rotation speed of the ceramic shaft 17 coincides with the rotation speed of the rotation stage 12. Further, the feeding of the tape core wire F to the front end side may be controlled using a ball screw mechanism or the like.

  Further, when the ceramic shaft 17 rotates following the movement of the tape core wire F, each optical fiber f and the peripheral surface of the ceramic shaft 17 are not displaced from each other, and the peripheral surface of the ceramic shaft 17 is not displaced. Friction with 171 is eliminated, and cracks are less likely to occur in each optical fiber f. In addition, the peripheral surface 171 of the ceramic shaft 17 is also heated. However, by rotating, only a part of the peripheral surface 171 is not continuously heated, and a significant local temperature increase is suppressed. . When the temperature of the peripheral surface 171 of the ceramic shaft 17 is significantly increased locally, fine cracks are likely to occur in the optical fiber f in contact with the markedly increased temperature portion. In this embodiment, however, the optical fiber f is also in this respect. Cracks are less likely to occur.

  Further, the optical transmission medium bending apparatus 10 has a tension applying means 18. In the present embodiment, the tension applying means 18 corresponds to an optical fiber holding jig 151 that moves to the tip end side of the tape core wire F on the height adjustment stage 15. As described above, the optical fiber holding jig 151 is movable in the longitudinal direction of the tape core F. However, when bending is performed and the tape core F starts to move to the tip side, a predetermined friction is obtained. It can move against force. Therefore, the optical fiber holding jig 151 according to the present embodiment applies a tension that is pulled toward the rear end side to the tape core wire F that is bent and moves toward the front end side by a predetermined frictional force. The tension here is about several gf to several tens of gf per optical fiber. By applying this slight tension, each optical fiber f can be bent tightly, and the accuracy for bending to a desired radius of curvature is further improved.

  When the bending process is completed, natural cooling is performed, and then the tape core F is removed from the optical transmission medium bending apparatus 10 to complete the forming of the tape core F. The bent tape core F can be manufactured using the optical transmission medium forming method described above.

  In addition, it is also possible to manufacture the optical transmission medium which has a bending | flexion in two or more places by repeating the optical transmission medium shaping | molding method of this invention. Specifically, a meandering optical fiber or the like can be formed by bending a plurality of portions of the optical transmission medium in order.

  By using an optical transmission medium whose optical path is freely changed as described above, a space-saving optical circuit can be manufactured.

  As described above, according to the optical transmission medium bending apparatus 10 of the present embodiment, the optical transmission medium is hardly cracked and the accuracy for bending to a desired radius of curvature is improved.

  Next, various adjustments of the optical transmission medium bending apparatus 10 of the present embodiment will be described. First, the heating temperature of the optical fiber f can be adjusted by adjusting the distance between the pair of arc discharge electrodes 16 and the heating portion of each optical fiber f. The heating temperature of the optical fiber f is preferably a temperature not lower than the strain point of the material constituting the optical fiber f and lower than the softening point. More preferably, it is above the annealing point and below the softening point. In addition, when the optical fiber f is comprised with the some material and the temperature is not the same, the highest temperature is employ | adopted. The softening point here is a value measured according to JIS-R3103-1, and the strain point and the annealing point are values measured according to JIS-R3103-2. In the present embodiment, the height position of the rotary stage 12 and the height position of the ceramic shaft 17 are both fixed, and the height positions of the pair of arc discharge electrodes 16 provided in the vertical portion 131 of the U-shaped bracket 13 are It can be changed. The distance between the pair of arc discharge electrodes 16 and the heated portion of each optical fiber f is adjusted by changing the height position of the pair of arc discharge electrodes 16. The means for changing the height position of the pair of arc discharge electrodes 16 corresponds to an example of the height adjusting means referred to in the present invention.

  The height adjustment stage 15 can be raised and lowered, and the optical fiber fixing arm 14 is attached to the rotary stage 12 in a replaceable manner. A plurality of optical fiber fixing arms 14 having different thicknesses W (see FIG. 1) of the optical fiber tip side mounting portion 140 are prepared. When the ceramic shaft 17 is changed to a peripheral surface having a different radius of curvature, the height adjustment stage 15 is moved up and down and the height of the height adjustment stage 15 is moved up and down along the optical fiber fixing arm 14. Replace with one of thickness W. That is, adjustment is made so that the tape core wire F spanned between the optical fiber tip side mounting portion 140 and the optical fiber holding jig 151 is in a straight line. The straight line here is not limited to horizontal, but may be oblique as described later.

  In the present embodiment, the height position of the rotary stage 12 and the height position of the ceramic shaft 17 are both fixed, but these height positions may be changed. When the height position of the rotary stage 12 is changed, the height position of the optical fiber tip side mounting portion 140 in the optical fiber fixing arm 14 attached to the rotary stage 12 also changes, and the height adjustment stage 15 is moved up and down. The tape core F spanned between the optical fiber tip side mounting portion 140 and the optical fiber holding jig 151 can be adjusted to be in a straight line.

  FIG. 8 is a view showing a modification of the optical transmission medium bending apparatus 10 shown in FIG. In the following description, the same reference numerals are given to the same components as those described so far, and duplicate descriptions are omitted.

  In the optical transmission medium bending apparatus 20 shown in FIG. 8, the optical fiber front end mounting portion 140 in the optical fiber fixing arm 14 is disposed obliquely so that the front end side is high and the rear end side is low. Similarly, the mounting surface 140a on which the front end side is mounted is also inclined. Further, the upper surface 15a of the height adjustment stage 15 on which the optical fiber holding jig 151 is provided is also inclined so that the front end side is high and the rear end side is low like the placement surface 140a, and the optical fiber holding jig 151 is similarly. It is arranged diagonally. The inclination angle of the mounting surface 140a of the optical fiber tip side mounting portion 140 and the inclination angle of the optical fiber holding jig 151 are equal. As a result, the tape core wire F is stretched in a straight line between the optical fiber front end side mounting portion 140 and the optical fiber holding jig 151 in a state of being inclined so that the front end side is high and the rear end side is low. In the optical transmission medium bending apparatus 20 shown in FIG. 8, the inclined optical fiber holding jig 151 corresponds to the tension applying means 18. That is, the tension | pulling tension | pulling toward the back end side is provided to the tape core wire F which is bent and moves to the front end side using gravity. The tilt angle of the upper surface 15a of the height adjustment stage 15 can be adjusted. The tilt angle is increased when the tension is increased, and the tilt angle is decreased when the tension is decreased. Further, the rotation stage 12 is rotated, and the optical fiber fixing arm 14 is rotated so that the inclination angle of the optical fiber tip side mounting portion 140 is the same as the inclination angle of the optical fiber holding jig 151.

  In the above description, the pair of arc discharge electrodes 16 are used. However, instead of the pair of arc discharge electrodes 16, other heating means (for example, a burner) for heating each optical fiber f in a non-contact manner. May be used. However, an arc discharge electrode is preferable from the viewpoint of efficiently heating the optical fiber at a high temperature.

  The ceramic shaft 17 is a cylindrical body, but an eyebrow type whose diameter gradually increases toward the center in the rotation axis direction may be used. This eyebrows type may have a different radius of curvature in the width direction and may be used when different curvature radii are desired to be obtained by a single bending process. Moreover, if it is a eyebrows type | mold, the distance of the intermediate temperature range of the arc discharge A and a ceramic shaft surrounding surface may be able to be made uniform by the width direction (rotating shaft direction).

  Hereinafter, further description will be made using examples.

  An L-shaped bracket made of aluminum was prepared as the L-shaped bracket 11 shown in FIG. 1, and a height adjustment stage for mounting an optical fiber holding jig for holding an optical fiber was attached to the pedestal portion. Further, as the rotary stage 12 shown in FIG. 1, an automatic θ-axis rotary stage driven by a stepping motor is prepared, and the automatic θ-axis rotary stage is attached to an aluminum L-shaped bracket wall surface (the standing portion 112 shown in FIG. 1). Fixed.

  Further, a U-shaped bracket made of glass epoxy was prepared as a pair of arc discharge electrodes and a U-shaped bracket 13 shown in FIG. Each of the pair of arc discharge electrodes is connected to an arc discharge power source (using an optical fiber fusion device manufactured by Furukawa Electric Co., Ltd.), and both the cathode and anode electrode bars are fixed facing the U-shaped bracket. The character-shaped bracket was fixed to the wall surface of the L-shaped bracket (the standing portion 112 shown in FIG. 1).

  An optical fiber fixing arm having an optical fiber tip side mounting portion is assembled to the automatic θ-axis stage, and a ceramic shaft 17 shown in FIG. 1 is provided at the rear end of the optical fiber tip side mounting portion 140 in the optical fiber fixing arm. A cylindrical zirconia optical fiber support having a radius of 1.3 mm and a length of 2.2 mm was attached.

  A quartz optical fiber (GI50 multimode, clad diameter 0.125 mm, coating outer diameter 0.25 mm, manufactured by Furukawa Electric Co., Ltd.) was used as the optical fiber, and the coating was removed from the tip to 30 mm. And the front end side of the part from which the coating was removed was fixed to the optical fiber fixing arm by a fixing plate. On the other hand, the rear end side of the optical fiber is held by an optical fiber holding jig. When the optical fiber holding jig moves to the tip side, a predetermined resistance force that prevents the movement acts. The optical fiber holding jig can apply a tension of about 10 gf.

  In addition, the vertical distance between the optical fiber and the center between the pair of arc discharge electrodes was adjusted to about 1 mm, and the optical fiber was heated red without contact by the arc discharge flame.

  The automatic θ-axis stage and the arc discharge power supply are connected to the controller, and while the arc discharge is performed, the automatic θ-axis stage is controlled to rotate 90 degrees at an angular velocity of π / 8 (rad / s). The optical fiber was bent 90 degrees along the arc of the fiber support.

  This experiment was repeated four times to measure the radius of curvature of the optical fiber. The actual measurement results are shown in Table 1.

The theoretical value of the radius of curvature at the bent portion of the optical fiber bent by 90 degrees is 1.3625 mm obtained by adding 0.625 mm which is a half of the clad diameter to the radius 1.3 mm of the optical fiber support which is a ceramic shaft. Become.

  As shown in Table 1, the actually measured value was slightly larger than the theoretical value, but almost coincided with the theoretical value.

  The optical fiber of Example 1 was a 4-fiber ribbon. Otherwise, the optical fiber was bent in the same manner as in Example 1, and the radius of curvature of the optical fiber was measured. Table 2 shows the actual measurement results.

The theoretical value is 1.3625 mm.

  As shown in Table 2, the actually measured value was slightly larger than the theoretical value, but almost coincided with the theoretical value.

  An optical transmission medium bending apparatus having the same configuration as the optical transmission medium bending apparatus 20 shown in FIG. 8 was used. Specifically, the optical fiber holding jig (upper surface of the height adjustment stage) was tilted by 10 degrees, the rotating stage was rotated in accordance with the tilt, and the optical fiber tip side mounting portion was also tilted by 10 degrees. Otherwise, the optical fiber was bent in the same manner as in Example 1, and the radius of curvature of the optical fiber was measured. Table 3 shows the measurement results.

The theoretical value is 1.3625 mm.

  As shown in Table 3, the actually measured value was slightly larger than the theoretical value, but almost coincided with the theoretical value.

  The optical fiber support, which is a ceramic shaft, had a radius of 5.0 mm and a length of 2.2 mm. Otherwise, the optical fiber was bent in the same manner as in Example 3, and the curvature radius of the optical fiber was measured. The actual measurement results are shown in Table 4.

The theoretical value of the radius of curvature is 5.0625 mm obtained by adding 0.625 mm which is a half of the clad diameter to the radius of 5.0 mm of the optical fiber support.

As shown in Table 4, the actually measured value was slightly larger than the theoretical value here, but almost coincided with the theoretical value.
<Evaluation>
(Variation of curvature radius)
For Examples 1 to 4, the difference between the maximum value and the minimum value of the measured radius of curvature was determined to be “variation of radius of curvature”.
(Scratch)
About the optical fiber of Examples 1-4, the presence or absence of the damage | wound of a surface was confirmed with the commercially available digital microscope. The evaluation results are shown in Table 5.

As shown in Table 5, in any of Examples 1 to 4, by bending the optical fiber along the optical fiber support which is a ceramic shaft, the variation in the radius of curvature can be reduced, and further, By rotating the optical fiber support following the movement of the fiber, the surface of the optical fiber could be bent without being damaged.

  In particular, in Example 3, by providing an inclination, it was possible to apply a stable tension by gravity to the optical fiber, and the variation in the radius of curvature could be made extremely small so as not to appear in effective figures.

  Moreover, in Example 4, the optical fiber was able to be bent with the desired curvature radius different from the curvature radius of Examples 1-3 by using the optical fiber support body from which a diameter differs.

DESCRIPTION OF SYMBOLS 10,20 Optical transmission medium bending apparatus 11 L-shaped bracket 12 Rotating stage 13 U-shaped bracket 14 Optical fiber fixing arm 140 Optical fiber front end side mounting part 141 Fixed plate 15 Height adjustment stage 151 Optical fiber holding jig 16 Arc discharge electrode 17 Ceramic shaft 171 Peripheral surface 18 Tension applying means F Tape core wire f Optical fiber

Claims (18)

Non-contact heating means for heating a part of the optical transmission medium spanned in a predetermined space in a non-contact manner;
A bending jig for bending by applying force to the optical transmission medium;
An optical transmission medium forming apparatus, comprising: a support member that contacts a portion of the optical transmission medium heated by the non-contact heating means from below.   The optical transmission medium forming apparatus according to claim 1, wherein the bending jig rotates around the vicinity of the non-contact heating means.   The optical transmission medium forming apparatus according to claim 1, further comprising tension applying means for applying tension to the optical transmission medium bent by the bending jig.   4. The optical transmission medium according to claim 1, wherein the support member has a cylindrical peripheral surface having a rotation axis orthogonal to the longitudinal direction of the optical transmission medium. 5. Molding equipment. This optical transmission medium molding device holds the optical transmission medium bent by the bending jig so as to be movable in the longitudinal direction of the optical transmission medium,
The lower support member has a cylindrical peripheral surface that rotates around the rotation axis following the movement of the optical transmission medium bent by the bending jig in the longitudinal direction. The optical transmission medium forming apparatus according to claim 4.   The optical transmission medium forming apparatus according to claim 1, wherein the support member is an insulator.   7. The optical transmission medium forming apparatus according to claim 1, wherein the non-contact heating means is an arc discharge electrode. An optical transmission medium molding method for bending an optical transmission medium using non-contact heating means,
A set process of linking the optical transmission medium to a predetermined space;
A bending process of applying a force to the optical transmission medium while bending a part of the optical transmission medium spanned in a predetermined space by a non-contact heating means,
The method for forming an optical transmission medium, wherein the bending step is a process performed in a state where a part of the optical transmission medium heated by the non-contact heating means is supported from below.   9. The optical transmission medium forming method according to claim 8, wherein the bending process is a process of bending the optical transmission medium using a bending jig capable of adjusting an angular velocity.   10. The optical transmission medium forming method according to claim 8, wherein the bending process is a process performed while applying tension to the optical transmission medium.   11. The method according to claim 8, wherein the bending process is a process using a cylindrical peripheral surface having a rotation axis orthogonal to a longitudinal direction of the optical transmission medium as the support member. An optical transmission medium forming method according to claim 1.   In the bending process, the optical transmission medium is held in a movable state in the longitudinal direction of the optical transmission medium, and the rotation is performed following the movement of the optical transmission medium in the longitudinal direction as the support member. 12. The method of forming an optical transmission medium according to claim 11, wherein the optical transmission medium forming method is a step of bending using a cylindrical peripheral surface that rotates about an axis.   The optical transmission medium forming method according to claim 8, wherein the bending step is a step of using an insulator as the support member.   14. The bending process according to claim 8, wherein the bending process is a process of bending the optical transmission medium using a bending jig that rotates around the vicinity of the non-contact heating means. The optical transmission medium shaping | molding method of description.   The optical transmission medium forming method according to claim 8, wherein the bending process is a process of bending the optical transmission medium by 90 degrees.   16. The optical transmission medium forming method according to claim 8, wherein the bending step is a step of using an arc discharge electrode as the non-contact heating means.   The method of forming an optical transmission medium according to claim 8, wherein a plurality of locations of the optical transmission medium are bent in order.   A method for producing an optical transmission medium, comprising the step of producing a bent optical transmission medium using the optical transmission medium forming method according to claim 8.