JP4359916B2 - Optical fiber cutting method - Google Patents

Description

  The present invention relates to an optical fiber cutter for cutting a core portion of an optical fiber, and an optical fiber cutting method using the same.

  In the optical communication field, an optical fiber is widely used as a medium for transmitting light, which is a signal propagation medium, to a distant place. This optical fiber consists of a thin glass core wire portion having an outer diameter of about 125 μm and a coating portion in which the outer periphery of the core wire portion is covered with a resin coating portion. The core part is composed of two parts having different refractive indexes called a core in the central part and a clad in the outer peripheral part, and the signal light mainly propagates through the core.

  Conventionally, optical fibers formed by connecting optical fibers of the same type by fusion or the like have been mainly used for connecting optical fiber cables in communication cable work, and the optical fiber cable has a certain length ( Therefore, a technique is used in which the cables are connected by fusion or the like when the optical fiber is extended or branched.

  When connecting the above optical fibers, it is necessary to remove and clean the optical fiber coating in advance and to perform a series of operations for cutting at a predetermined length. In order to measure the length of the optical fiber, a method is used in which an operator uses a gauge or the like to set the cut surface visually with reference to the tip of the covering portion. As a method of cutting such an optical fiber at a predetermined cutting surface position, a technique using a hard metal cutting blade is widely used.

  FIG. 11 is a perspective view showing a conventional optical fiber cutter, and a method for cutting an optical fiber using the same will be described.

  First, after the coating of the tip of the optical fiber 1 is removed by a jig called a jacket remover, the cleaned coating of the optical fiber 1 is fixed by the holding unit 2 and installed on the stage 5.

  Next, the optical fiber 1 is clamped with the clamping unit 6 closed, and the blade unit 7 is slowly slid from the front to the back, and the blade 71 is wound on the coating removal unit of the optical fiber 1. Thereafter, the hammer 65 is pushed down to apply a bending stress to the optical fiber 1. As a result, cracks rapidly develop starting from the previous wound part, and as a result, the optical fiber 1 is brittlely broken starting from the wound site and cut.

  Note that the wound position can be set to a desired position by visually locating the end face of the holding portion 2 in advance at a predetermined position of the gauge 9, and as a result, the cut length of the optical fiber 1 can be set to an arbitrary length. Can be set to

  By using such a technique, quartz glass, which is the main composition of the optical fiber, is a brittle material and can be easily broken by applying a load to a small number of cracks. Since the cut surface by such a break becomes a very good smooth surface, it is widely used as a method for cutting an optical fiber (see Patent Document 1).

After the optical fiber cut into a predetermined length by the above operations is melted with another optical fiber by discharge, the optical fiber glass is melted and then connected by fusion welding to connect each optical fiber. Obtainable.
JP-A-6-148456

  However, when the optical fiber connected as described above is manufactured, in order to precisely cut the optical fiber to a predetermined length, the cutting length is set by aligning the tip of the holding portion 2 with the gauge 9 and thereby setting the predetermined length. However, this has a drawback that it is difficult to ensure accuracy because the operator visually adjusts the reference.

  Further, each time an operator performs a fine adjustment by aligning the end of the holding unit 2 with the gauge 9, an increase in work time is caused.

  Further, the position that the operator uses as a reference when cutting is the end of the holding unit 2, but the end face is not smooth and is not suitable for the reference position for cutting. However, the accuracy of about ± 0.3 mm could not be obtained.

  In addition, when it is necessary to cut with a plurality of cutting lengths, it is necessary to realign the gauge position each time, and an error is likely to increase and errors are likely to occur.

An optical fiber cutting method according to the present invention includes a holding unit that holds a coating part of an optical fiber, and a first holding part that holds the core part from which the coating of the tip part of the optical fiber has been removed at two positions with an interval therebetween and a second clamping portion, is disposed between the front Symbol holder the second clamping portion, and a positioning member for positioning the holder at a predetermined position, and wherein the front Symbol first clamping portion second clamping portion located between, using an optical fiber cutter having a blade that wound to the optical fiber moves perpendicular to the axis direction of the optical fiber, the second optical fiber joined to the distal end of the first optical fiber An optical fiber cutting method for cutting to a predetermined length, wherein the holding portion holds the covering portion of the first optical fiber, the holding portion is arranged at a predetermined position by a first positioning member, and then the first holding The core wire portion is sandwiched between the portion and the second clamping portion. Holding the blade, moving the blade perpendicular to the axial direction of the first optical fiber to wound the core wire portion, applying a bending stress to cut the first optical fiber, and then cutting the first optical fiber on the cut surface. A second optical fiber is joined, and the holding portion is disposed at another predetermined position by a second positioning member having a thickness different from that of the first positioning member by a predetermined length, and then the first clamping portion and the second clamping portion are arranged. The core portion of the second optical fiber is sandwiched by the portion, and the second optical fiber is cut to the predetermined length .

Further, the method of cutting the optical fiber of the present invention is characterized by using an elastic member for elastically drag load so as to abut against the positioning member in the axial direction of the optical fiber pre-Symbol holder.

Furthermore, the method of cutting the optical fiber of the present invention, before Symbol positioning member, characterized by using a spacer having a predetermined thickness.

  According to the optical fiber cutter of the present invention, an optical fiber cutter that cuts the core portion of the optical fiber from which the coating of the tip portion is removed to a predetermined length, the holding portion that holds the coating portion of the optical fiber, and the core portion A first sandwiching portion and a second sandwiching portion that are held open, and a positioning member that is disposed between the retaining portion and the second sandwiching portion and places the retaining portion at a predetermined position. Since it has a blade that cuts the optical fiber by moving perpendicularly to the axial direction of the optical fiber, it is stable depending only on the shape and thickness of the positioning member. Thus, the holding portion can be positioned, and as a result, the optical fiber can be cut with a precise cutting length.

  In addition, the optical fiber cutter of the present invention includes an elastic member that elastically loads the holding portion so as to contact the positioning member in the axial direction of the optical fiber, so that the positioning member is repeatedly positioned due to rattling of the positioning member. It is possible to prevent the accuracy from deteriorating.

  Furthermore, in the optical fiber cutter according to the present invention, since the positioning member is made of a spacer having a predetermined thickness, spacers of various thicknesses are arranged between the holding portion and the second holding portion at the end according to a desired cutting length. It is possible to easily and stably control the cutting length simply by installing and pinching.

  Still further, in the method for cutting an optical fiber using the optical fiber cutter of the present invention, the optical fiber coating portion is held by the holding portion, the holding portion is positioned at a predetermined position by the positioning member, and then the first holding portion is The core wire portion is clamped by the second clamping portion, the blade is moved perpendicularly to the axial direction of the optical fiber, wound on the core wire portion, and then subjected to bending stress on the core wire portion and then cut. The cutting length can be easily and accurately adjusted by the member, and a desired optical fiber can be obtained.

  Further, the optical fiber cutting method using the optical fiber cutter of the present invention is such that after the optical fiber is cut by the method described above, another optical fiber is fused to the cut surface, and the holding portion is separated by a different positioning member. Is placed at another predetermined position, and thereafter, the core portion of the fused optical fiber is sandwiched by the first sandwiching portion and the second sandwiching portion, and the optical fiber is cut based on the fused surface. Since the position of the new cut surface based on the contact surface is stably determined only by the difference in the shape of each positioning member, and the positioning accuracy depends only on the geometric dimension accuracy of each positioning member, Highly accurate cutting length control is possible.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a perspective view showing an embodiment of an optical fiber cutter according to the present invention, in which a core portion 12 of an optical fiber 1 from which a coating on a tip portion has been removed is cut to a predetermined length. A holder 2 that is a holding part for holding the covering part 11, a first holding part 61 and a second holding part 62 that hold the core part 12 at a predetermined interval, and the holding part 2 and the second holding part 62 And a positioning member 4 that positions the holding portion 2 at a predetermined position, and is positioned between the first clamping portion 61 and the second clamping portion 62, with respect to the axial direction of the optical fiber 1. The holding unit 2, the clamping unit 6, and the blade unit 7 are installed on the stage 5 and further include the blade unit 7 as a base. 8 is supported.

  Next, the structure of this optical fiber cutter will be described with the optical fiber 1 provided, with reference to FIGS.

  FIG. 2 is a schematic view showing a state in which the optical fiber 1 is held by the holder 2. First, the covering portion 11 of the optical fiber 1 is installed in the V-groove 23, and the core wire portion 12 protrudes from the holder base 22 by a predetermined length. . Next, when the optical fiber clamps 21 a and 21 b are closed, the covering portion 11 is sandwiched and fixed between the elastic members 24 a and 24 b and the V groove 23. The elastic members 24a and 24b may be made of a material such as rubber having an elasticity that does not leave a dent or the like on the covering portion 11 of the optical fiber 1.

  A state where the holder 2 holding the optical fiber 1 is set in the optical fiber cutter main body will be described with reference to FIGS. 3 and 4.

  For the sake of explanation, the clamping portion 6 is omitted in FIG. In FIG. 4, a part of the clamping unit 6 is omitted.

  One end of the holder 2 needs to abut on the positioning member 4 in order to adjust the cutting position of the optical fiber 1, and the holder 2 can be easily moved by rattling or the like during the abutment. If this happens, the cutting position of the optical fiber 1 cannot be adjusted with high accuracy. Therefore, as shown in FIG. 4, it is preferable that one end of the holder 2 is brought into contact with the positioning member 4 side by the elastic force of the elastic member 3. The elastic member 3 includes ball plungers 31a and 31b, a base 32, and an optical fiber groove 33, and is attached so as to press the holder 2 holding the optical fiber 1 in the direction of the arrow in the figure. At this time, the ball plungers 31 a and 31 b are pressed against the holder 2, and as a result, a drag is generated by the springs in the ball plungers 31 a and 31 b, and the holder 2 is elastically pushed back toward the positioning member 4. Thus, the cutting position of the optical fiber 1 can be adjusted with high accuracy.

  The elastic member 3 may be any mechanism as long as it has sufficient elasticity to fix the holder 2 in addition to the method using the ball plungers 31a and 31b.

  As described above, by using the positioning member 4 and holding the holder 2 using the elastic force of the elastic member 3, the cutting position of the optical fiber 1 is accurately set to a predetermined position determined by the shape of the positioning member. Can be positioned.

  Further, as the positioning member 4, it is preferable to fix the holder 2 at a predetermined position by sandwiching a plate-like spacer having a predetermined thickness as shown in FIG. 4 between the holder 2 and the second clamping part 62, When a spacer is used, as will be described in detail later, by preparing a plurality of different thicknesses, the holder 2 can be positioned at a plurality of positions, and the optical fiber 1 can be cut to a desired cutting length. it can.

  The spacer is preferably made of a material such as ceramic or hard metal that is hard to wear and can be processed with high accuracy.

  In addition, any shape can be used as long as the holder 2 can be appropriately positioned, such as a cylindrical spacer.

  As described above, after the covering portion 11 of the optical fiber 1 is held and positioned by the positioning member 4, the core wire portion 12 is clamped by the first clamping portion 61 and the second clamping portion 62 as shown in FIG.

  Note that FIG. 5 shows only the sandwiching portion 6 and the core wire portion 12 for explanation.

  The core portion 12 of the optical fiber 1 is installed so as to be horizontally passed to the first sandwiching portion 61 and the second sandwiching portion 62, and the sandwiching portion base 63 is rotated around the hinge 64 so as to be connected to the first sandwiching portion 61. The second clamping unit 62 is closed and clamped.

  The distance between the first clamping part 61 and the second clamping part 62 is preferably about 10 mm, and the width of the first clamping part 61 and the second clamping part 62 is preferably about 4 mm. As a result, a sufficient clamping force can be generated with respect to the load applied from the blade when the core wire portion 12 is cut, and as a result, the optical fiber 1 can be cut stably.

  A blade unit 7 as shown in FIG. 6 is provided below the clamping unit 6.

  In addition, in FIG. 6, illustration of the clamping part 6 and the base 8 is abbreviate | omitted for description.

  The blade of the blade unit 7 moves in the direction perpendicular to the axial direction of the optical fiber 1, that is, in the direction shown by the arrow in FIG. 6 and wounds on a part of the surface of the core portion 12 of the optical fiber 1. The blade unit 7 is composed of a blade 71, a slide 72, and a rail 73. The blade 71 is a low wear metal such as tungsten carbide or a super hard metal with a diamond coat in order to avoid deterioration of cutting performance due to wear. It is desirable to use

  Furthermore, in order to maintain the position of the blade 71 with respect to the optical fiber 1 with high accuracy, it is desirable to use a high-precision linear motion mechanism such as a linear stage using a high-precision bearing for the slide 72 and the rail 73.

  Here, a method for cutting the optical fiber 1 using the above-described optical fiber cutter will be described.

  First, as shown in FIG. 7, the optical fiber 1 held as shown in FIGS. 2 to 6 is moved in the direction indicated by the arrow in the hammer 65 slidably installed in the center of the clamping part 6. Slide. The hammer 65 pushes down the core part 12 downward. At this time, the core wire part 12 is sandwiched between the first sandwiching part 61 and the second sandwiching part 62, so that a bending stress is applied to the core wire part 12. Here, since the core wire portion 12 is wounded by the blade 71, the core wire portion 12 is cut starting from the wound.

  The positioning member 4 used for the cutting is the first spacer, and the thickness thereof is not particularly limited, but it is preferable to use a thickness of about 1 mm from the viewpoint of spacer strength and handling. desirable.

  Next, as shown in FIG. 8, the core wire portion of another optical fiber 13 is fused to the cut surface of the core wire portion 12 of the optical fiber 1 to form a fusion point 14.

  Next, as shown in FIG. 9, the first spacer that is the positioning member 4 is changed to the second spacer that is another positioning member 41 having a larger thickness than the first spacer. As a result, the holder 2 moves away from the blade 71 by the difference in thickness between the first spacer and the second spacer. At the same time, the fusion point 14 is also moved away from the blade 71 by the same distance. As a result, the fusion point 14 and the blade 71 are separated by a distance equal to the difference in thickness between the first spacer and the second spacer.

  After that, the blade 71 is moved perpendicularly to the axial direction of the optical fiber 1 and wound on the core portion of the optical fiber 13 in the same manner as in the previous cutting, and then a bending stress is applied to cut the blade 71 to a predetermined length.

  As shown in FIG. 10, the optical fiber 1 cut by such a method has a new cut surface 15 formed by cutting. The distance from the fusion point 14 to the cut surface 15 is the same as that shown in FIG. As described in the description, it becomes equal to the difference in thickness between the first spacer and the second spacer, and the cutting accuracy is determined depending on the accuracy of the thickness of each spacer.

  As described above, by managing the cutting length when the optical fiber 1 is cut by the positioning member 4, it is possible to adjust more easily and accurately than when using a gauge. In addition, the work time required at that time is only to insert the spacer at most, and the work can be simplified and speeded up. In addition, the mechanism can be simplified and the failure can be reduced. Furthermore, by preparing a plurality of spacers having different thicknesses, even when it is necessary to cut with many optical fiber lengths, replacement and cutting can be performed quickly, and tact improvement can be achieved. Moreover, since the cutting length accuracy is determined by the processing accuracy of each spacer thickness, once the spacer is processed with high accuracy, the cutting length can be controlled with a constant accuracy regardless of the skill level of the operator.

  A comparative experiment was conducted in which an optical fiber was cut using an optical fiber cutter according to the present invention and a conventional optical fiber cutter.

  The experiment is based on the fusion splicing surface of the optical fiber, positioning the optical fiber so that it can be cut at a predetermined target length, measuring the cut length after cutting, and how much difference is from the target length. Evaluation was performed.

  In the present invention, a spacer is used as the positioning member 2 using an optical fiber cutter as shown in FIG. Conventionally, the position was visually measured using an optical fiber cutter as shown in FIG.

  The optical fiber used in the experiment is a single mode optical fiber made of quartz glass having a core wire portion diameter of 0.125 mm and a covering portion diameter of 0.9 mm. The coating on the tip was previously removed over a length of about 20 mm and washed with ethanol.

  First, the spacer used in the experiment in the optical fiber cutter according to the present invention will be described. In this experiment, spacers A and B having different thicknesses are used, and the thicknesses are 1.0 mm and 1.8 mm, respectively. The spacer material was zirconia ceramics.

  Next, an experimental method in the optical fiber cutter according to the present invention will be described.

  First, the holder holding the optical fiber is positioned using the spacer A, and the first cutting is performed. Next, a new silica glass single mode optical fiber is fusion-spliced to the cut optical fiber. Finally, the optical fiber after the fusion splicing is positioned using the spacer B, and the second cutting is performed. At this time, the distance between the newly formed cut surface and the fusion surface formed by the immediately preceding fusion connection is measured, and this distance is 0.8 mm, which is the difference between the thicknesses of spacer A and spacer B. Calculate and record the difference.

  Next, an experimental method in a conventional optical fiber cutter will be described.

  First, the end of the holder holding the optical fiber is visually positioned according to the gauge origin, and the first cutting is performed. Next, a new quartz glass single-mode optical fiber is fused and connected to the cut optical fiber. Finally, the holder end portion is positioned at a gauge of 0.8 mm while holding the optical fiber after the fusion splicing, and the second cutting is performed. At this time, the distance between the newly formed cut surface and the fused surface formed by the immediately preceding fused connection is measured, and the difference between this distance and the gauge setting length of 0.8 mm is calculated and recorded. To do.

  About the above experiment, working time, connection loss, and cutting length were measured for each cutter. Hereinafter, each measurement method will be described.

  First, the working time was measured with a stopwatch from the moment when the optical fiber was held by the holder to the moment when the second cutting was completed. As for the connection loss, the optical fiber after the second cutting is fused to the optical fiber connected to the measurement system, signal light of a predetermined wavelength is incident, the output is measured, and the incident light intensity and output are measured. The ratio of incident light intensity was calculated as loss. Finally, regarding the cut length, the distance from the fused surface to the cut surface formed by the second cut was measured with a factory microscope. The magnification is 100 times.

  The number of samples was set to 10 for both cutters, and the average was calculated for each of the working time, connection loss, and disconnection error, and the values of the present invention were calculated with the conventional cutter set to 1 for comparison.

In addition, it is preferable that each measured value has a small value.

  As shown in Table 1, it can be seen that the optical fiber cutter according to the present invention has a better value than the conventional optical fiber cutter at any measured value.

  In particular, the accuracy of cutting error is improved by 3 times or more, and the effect of improving the positioning accuracy by the spacer can be understood. In addition, the working time at that time is shortened by 20% or more, and it can be seen that the productivity is improved. In addition, it has been found that the connection loss at that time has a better value than before, and there is no problem in optical performance.

It is a perspective view which shows the state which installed the optical fiber in the optical fiber cutter of this invention. It is a perspective view which shows the structure and operation | movement of a holding | maintenance part in the optical fiber cutter of this invention. It is a perspective view which shows the attachment operation | work of the holding | maintenance part in the optical fiber cutter of this invention. It is a perspective view which shows the structure and operation | movement of a positioning member in the optical fiber cutter of this invention. It is a perspective view which shows the structure and operation | movement of a clamping part in the optical fiber cutter of this invention. It is a perspective view which shows the structure and operation | movement of a blade unit in the optical fiber cutter of this invention. It is a perspective view which shows the cutting method of the optical fiber using the optical fiber cutter of this invention. It is a perspective view which shows the optical fiber after the optical fiber fusion | melting in the cutting method of the optical fiber of this invention. It is a perspective view which shows the operation | movement in the cutting method of the optical fiber of this invention. It is a perspective view after the cutting | disconnection in the cutting method of the optical fiber of this invention. It is a perspective view which shows the conventional optical fiber cutter.

Explanation of symbols

1: optical fiber 11: coating portion 12: core wire portion 13: fused optical fiber 14: fusion point 15: end face 2: holder 21a: optical fiber clamp 21b: optical fiber clamp 22: base 23: V groove 24a: elastic member 24b: elastic member 3: elastic member 31a: spring plunger 31b: spring plunger 32: base 33: slit 4: positioning member 41: positioning member 5: stage 6: clamping unit 61: first clamping unit 62: second clamping unit 63 : Clamping part base 64: hinge 65: hammer 7: blade unit 71: blade 72: slide 73: rail 8: base 9: gauge

Claims (3)

A holding unit for holding the covering portion of the optical fiber, a first clamping portion and a second clamping portion covering the tip portion is held in two places at intervals core part removed of the optical fiber, before Symbol retention is arranged between the parts and the second clamping portion, and a positioning member for positioning the holder at a predetermined position located between the front Symbol first clamping portion and a second clamping portion, the axis of said optical fiber using an optical fiber cutter having a blade that wound to the optical fiber moves perpendicular to the direction, the method of cutting the optical fiber to cut the second optical fiber joined to the distal end of the first optical fiber to a predetermined length The covering portion of the first optical fiber is held by the holding portion, and the holding portion is disposed at a predetermined position by the first positioning member, and then the core wire is formed by the first holding portion and the second holding portion. Sandwiching the portion, the blade is the first optical fiber The first optical fiber is cut by applying a bending stress to the first optical fiber, and then joining the second optical fiber to the cut surface. The holding portion is disposed at another predetermined position by the second positioning member having a thickness different from the positioning member by the predetermined length, and then the core portion of the second optical fiber is moved by the first holding portion and the second holding portion. A method for cutting an optical fiber, wherein the optical fiber is sandwiched and the second optical fiber is cut into the predetermined length. The method of cutting an optical fiber according to claim 1, characterized in that an elastic member for elastically drag load so as to abut against the positioning member in the axial direction of the optical fiber pre-Symbol holder. To the positioning member, the method of cutting an optical fiber according to claim 1 or 2, characterized by using a spacer having a predetermined thickness.

Images