JP2021148870A - Optical fiber holding tool - Google Patents

Abstract

To provide an optical fiber holding tool for winding and fixing an optical fiber, which suppresses output reduction in the optical fiber.SOLUTION: An optical fiber holding tool includes a winding core part 110 around which an optical fiber is wound, and a pressing part 30 for pressing an optical fiber LF wound around the winding core part against inside the winding core part, in which a plane shape of a contact part 34 in contact with the optical fiber has substantially a circular arc shape. The winding core part includes a first member 10 having a plurality of circular arc parts 11 having substantially circular arc shapes and at least one recess 13, and having a flat plate shape, and a second member 20 that is movable at a first position where the optical fiber wound around the winding core part is made to have substantially an annular shape and a second position where the optical fiber is made to have such an annular shape as to have a curved unevenness, in which a plane shape of an outer peripheral part 24 as the outer periphery of the winding core part is formed into substantially a circular arc shape. The pressing part is fixed in a state where the optical fiber is pressed toward the recess of the first member.SELECTED DRAWING: Figure 3

Description

The present invention relates to an optical fiber holder.

In an optical fiber, for example, in an optical fiber used for a fiber laser, excitation light is efficiently absorbed by the core to improve the output. Conventionally, as a method of efficiently absorbing the excitation light into the core, it is known to bend and bundle an optical fiber having a length of several meters to several tens of meters (see Non-Patent Document 1).

On the other hand, as a method for facilitating the excitation light from entering the core, there is a method in which the cross-sectional shape of the clad of the optical fiber is changed from a circular shape to a polygonal shape or further twisted (see, for example, Patent Documents 1 to 3). ..

Japanese Patent No. 6255532 International Publication No. 2003/067722 Japanese Patent No. 5469064

"High-Power Diode Lasers", R.M. Diehl, Springer, P381

In the technique described in Non-Patent Document 1, a support column is erected and an optical fiber is wound around the support column to form a so-called kidney shape. However, in the technique described in Non-Patent Document 1, since the curvature of bending cannot be controlled, when the curvature of bending becomes small, the excitation light is emitted to the outside and the excitation light can be efficiently absorbed by the core. However, there is a risk that the output will decrease. Further, there is also a problem that it is difficult to carry because the optical fiber is not fixed and it is not practical.

Further, as in the techniques described in Patent Documents 1 to 3, even in an optical fiber having a polygonal or twisted clad shape in a cross section orthogonal to the optical axis, a double clad fiber that efficiently absorbs excitation light is used. However, there is a problem that the cost is high. Further, in an optical fiber having corners inside, stress concentration occurs at the corners when bent, so it is preferable to increase the curvature of bending. Therefore, a large space is required in terms of equipment.

An object of the present invention is to provide another technique for suppressing a decrease in the output of an optical fiber in an optical fiber holder for winding and fixing the optical fiber.

The present invention has been made to solve at least a part of the above-mentioned problems, and can be realized as the following forms.

(1) According to one embodiment of the present invention, an optical fiber holder is provided. This optical fiber holder is a winding core portion in which the optical fiber is wound around its own outer circumference, and a pressing portion that presses the optical fiber wound around the outer circumference of the winding core portion toward the inside of the winding core portion. The winding core portion is provided with a pressing portion having a substantially arcuate planar shape of the contact portion in contact with the optical fiber, and the winding core portion is a flat surface having a plurality of substantially arcuate arcuate portions and at least one concave portion. A first member having a flat plate shape, a first position in which at least a part of itself is arranged in the recess and the optical fiber wound around the outer periphery of the winding core portion is formed into a substantially annular shape, and the winding core portion. The plane shape of the outer peripheral portion which is the second member which is movable to the second position where the optical fiber wound around the outer circumference of the winding core is made circular with curved irregularities and which is the outer circumference of the winding core portion is substantially defined. A second member formed in an arc shape is provided, and the pressing portion is fixed in a state where the optical fiber is pressed toward the recess of the first member.

According to this configuration, in the optical fiber holder, the winding core portion includes the first member and the second member, and the second member is configured so that the position in the recess of the first member can be changed. After the optical fiber is wound around the outer periphery of the winding core portion with the member arranged at the first position, the second member is moved to the second position, and the optical fiber is pressed toward the recess at the pressing portion to be fixed. By doing so, the optical fiber wound around the outer periphery of the winding core portion can be easily formed into an annular shape having curved irregularities. Further, according to this configuration, since the optical fiber can be fixed and held in an annular shape having curved irregularities, the reflection angle in the optical fiber changes sequentially, and the excitation light passes through the core of the clad fiber. It becomes easy to be absorbed, and the output of the optical fiber can be improved. Further, since the optical fiber is fixed in a wound state along the arc portion of the first member and the substantially arc-shaped contact portion of the pressing portion, the curvature of the contact portion between the arc portion of the first member and the pressing portion. A predetermined curvature can be added according to the above, and the optical fiber wound in an annular shape can be easily controlled to an appropriate curvature. Therefore, it is possible to suppress a decrease in the output of the optical fiber due to the small curvature.

(2) In the optical fiber holder of the above-described embodiment, the first member includes one recess, two first arc portions arranged on both sides of the recess, and two first arc portions. It may have a planar shape composed of a second arc portion having a diameter larger than that of the first arc portion connected to the end. In this way, the optical fiber wound in an annular shape can be made into a so-called kidney shape.

(3) In the optical fiber holder of the above-described embodiment, the ratio of the first arc portion to the second arc portion may be approximately 1: 3. In this way, cracking of the optical fiber and emission of excitation light can be appropriately suppressed.

(4) The recess of the first member has a planar shape having two parallel lines, and the second member and the pressing portion are configured to be movable along the two parallel lines of the recess. It may have been done. In this way, the second member and the pressing portion can be moved on the same straight line at the same time with the optical fiber sandwiched between the second member and the pressing portion. Therefore, it is possible to more stably and easily impart an appropriate curvature to the optical fiber.

(5) The optical fiber holder of the above-described embodiment may be provided with a cooling unit for cooling the optical fiber. In this way, the heat generated in the optical fiber can be released by the optical fiber holder. Therefore, the temperature rise of the optical fiber can be suppressed.

(6) In the optical fiber holder of the above-described embodiment, the outer peripheral surface of the first member may be formed of a metal having high thermal conductivity. In this way, the heat generated in the optical fiber can be released more efficiently. Therefore, the temperature rise of the optical fiber can be further suppressed.

The present invention can be realized in various aspects, for example, in the form of a processing device including an optical fiber holder, a processing device communication device including an optical fiber holder, an optical fiber holding method, and the like. be able to.

It is explanatory drawing which shows schematic structure of the optical fiber holder in 1st Embodiment. It is explanatory drawing which shows schematic the plane structure of the optical fiber holder. It is explanatory drawing of the arrangement position of the 2nd member. It is explanatory drawing which shows the winding method of the optical fiber using the optical fiber holder. It is explanatory drawing which shows the winding method of the optical fiber using the optical fiber holder. It is explanatory drawing which shows the schematic structure of the optical fiber holder of 2nd Embodiment. It is explanatory drawing which shows the schematic structure of the optical fiber holder of the modification.

<First Embodiment>
FIG. 1 is an explanatory diagram schematically showing the configuration of the optical fiber holder 100 according to the first embodiment. FIG. 2 is an explanatory view schematically showing a planar configuration of the optical fiber holder 100. The optical fiber holder 100 winds and fixes the optical fiber. In this embodiment, the optical fiber is used in an industrial laser processing apparatus. In other embodiments, optical fibers used for various purposes such as communication and lighting may be held.

The optical fiber holder 100 has a pressing portion 30 that presses the winding core portion 110 around which the optical fiber LF is wound around its own circumference and the optical fiber LF wound around the outer circumference of the winding core portion 110 toward the inside of the winding core portion. And two holding portions 50 for holding the wound state of the optical fiber LF, and a pedestal portion 40 in which the winding core portion 110, the pressing portion 30, and the holding portion 50 are arranged.

As shown in FIG. 2, the optical fiber LF is wound around the outer circumference of the winding core portion 110 and pressed toward the inside of the winding core portion 110 by the pressing portion 30 to form a so-called kidney shape (kidney bending). It is wrapped in a ring.

The winding core portion 110 includes a first member 10 and a second member 20. As shown in FIG. 2, the first member 10 is connected to one recess 13, two first arc portions 11 arranged on both sides of the recess 13, and the ends of the two first arc portions 11. It is formed in a flat plate shape composed of a second arc portion 12 having a diameter larger than that of the arc portion. The ratio of the first radius R1 of the first arc portion 11 to the second radius R2 of the second arc portion 12 is 17:50, which is approximately 1: 3. The recess 13 has a planar shape having two parallel lines 14. The first arc portion 11 and the second arc portion 12 are also simply referred to as "arc portions".

The second member 20 has an oval (rounded rectangle) planar shape composed of two parallel lines of equal length and two arcs, and is arranged in the recess 13 of the first member 10 and has two recesses 13. It is configured to be movable in the direction of an arrow along the parallel line 14 of. In FIG. 2, the arc-shaped outer peripheral portion 24 arranged below the drawing constitutes a part of the outer peripheral portion of the winding core portion 110.

The pressing portion 30 is formed in the same shape as the second member 20. As shown in the figure, the pressing portion 30 is arranged outside the winding core portion 110, the optical fiber LF is sandwiched between the second member 20 and the pressing portion 30, and the optical fiber LF is directed toward the recess 13 of the first member 10. Is fixed in the pressed state. In the pressing portion 30, the planar shape of the contact portion 34 in contact with the optical fiber LF is substantially arcuate. Like the second member 20, the pressing portion 30 is also configured to be movable in the direction of the arrow along the two parallel lines 14 of the recess 13.

The pedestal portion 40 is a substantially rectangular flat plate with a chamfered angle of 45 °. The first member 10 is fixed to the pedestal portion 40, and the second member 20 and the pressing portion 30 are moved in the direction of the arrow along the two parallel lines 14 of the recess 13 of the first member 10. A groove 42 is formed for this purpose. As shown in FIG. 1, the pressing portion 30 includes a protruding portion 32 that fits into the groove portion 42 of the pedestal portion 40. The user fits the protrusion 32 of the pressing portion 30 into the groove portion 42 and moves the pressing portion 30 along the groove portion 42 so as to follow the two parallel lines 14 (FIG. 2) of the recess 13 of the first member 10. It can be moved in the direction of the arrow (FIG. 2). Since the second member 20 also has the same protrusion (not shown) as the pressing portion 30, it can be similarly moved along the groove portion 42. Further, the pedestal portion 40 is configured so that the second member 20 and the pressing portion 30 can be fixed at a predetermined position. The optical fiber holder 100 of the present embodiment is attached to an industrial laser processing machine via a pedestal portion 40.

The holding portion 50 is formed in a columnar shape and is fixed to the pedestal portion 40. As shown in FIG. 2, the optical fiber LF is sandwiched between the two holding portions 50 and the first member 10, and is sandwiched between the second member 20 and the pressing portion 30 to maintain the kidney shape.

In the present embodiment, the first member 10, the second member 20, the pressing portion 30, and the holding portion 50 are made of copper. Since copper has high thermal conductivity, the heat generated in the optical fiber LF can be efficiently released. As a result, it is possible to suppress the occurrence of melting, optical destruction, spectrum change, etc. of the optical fiber LF. In other embodiments, metals having high thermal conductivity such as aluminum, silver and gold, alloys containing at least one of the metals having high thermal conductivity, high thermal conductivity ceramics such as silicon carbide and aluminum nitride, carbon nanotubes, etc. A material having high thermal conductivity such as a carbon material such as carbon fiber and a dense carbon material can be used. Further, these materials having high thermal conductivity may form a surface in contact with the optical fiber LF, and other parts may be formed of another material. For example, the outer peripheral surface of the first member 10 having a large contact area with the optical fiber LF may be formed of silver, and the other portion may be formed of a material having a lower thermal conductivity than silver. As the material having high thermal conductivity, a material having a thermal conductivity of 100 (W / m / K) or more is preferable.

The material of the pedestal portion 40 is not particularly limited. It may be formed of the same material as at least one of the first member 10, the second member 20, the pressing portion 30, and the holding portion 50, or may be formed of a material having low thermal conductivity such as resin. For example, it may be formed by using a rubber material or the like to ensure vibration absorption and insulation.

FIG. 3 is an explanatory diagram of the arrangement position of the second member 20. As described above, the second member 20 is configured to be movable along the two parallel lines 14 (FIG. 2) of the recess 13 of the first member 10. Specifically, it is possible to move from the first position shown on the left side of FIG. 3 to the second position shown on the right side of FIG. 3, and conversely, it is also possible to move from the second position to the first position. The first position (left view of FIG. 3) is a position where the optical fiber LF wound around the outer circumference of the winding core portion 110 is formed into a substantially annular shape, and the most protruding position P1 of the outer peripheral portion 24 of the second member 20 is. It protrudes from the opening position of the recess 13 of the first member 10, and further protrudes from the first arc portion 11 of the first member 10. The second position (right figure in FIG. 3) is a position where the optical fiber LF wound around the outer circumference of the winding core portion 110 is made into an annular shape having curved irregularities, and is the most protruding position of the outer peripheral portion 24 of the second member 20. The position P1 is arranged in the recess 13 of the first member 10.

4 and 5 are explanatory views showing a method of winding the optical fiber LF using the optical fiber holder 100. First, as shown in FIG. 4A, in the optical fiber holder 100, the pressing portion 30 and the two holding portions 50 are removed, and the second member 20 is arranged at the first position. As shown in the figure, the second member 20 includes a protrusion 22 that fits into the groove 42 of the pedestal 40. The user fits the outer peripheral portion 24 of the second member 20 into the groove portion 42, moves the second member 20 along the groove portion 42, and fixes the second member 20 to the pedestal portion 40 with a screw or the like. As a result, the shape of the winding core portion 110 is fixed in a state where the second member 20 is arranged at the first position (FIG. 3).

Next, as shown in FIG. 4B, the optical fiber LF is wound around the outer circumference of the winding core portion 110. At this time, the optical fiber LF is wound so as not to be loosened, and tension is generated in the optical fiber LF wound around the winding core portion 110. In this step, since the second member 20 is arranged at the first position and the outer peripheral portion 24 of the second member 20 protrudes from the first arc portion 11 of the first member 10, the optical fiber LF can be easily used. , Wrapped in a substantially circular ring.

After that, as shown in FIG. 5A, the two holding portions 50 are fixed to the pedestal portion 40. The holding portion 50 is fixed by screws using the screw holes 44 (FIG. 4) of the pedestal portion 40. As a result, the wound state of the optical fiber LF is maintained.

Finally, as shown in FIG. 5B, the pressing portion 30 is arranged so as to sandwich the optical fiber LF between the contact portion 34 of the pressing portion 30 and the outer peripheral portion 24 of the second member 20, and the second member 20 Is released, and the pressing portion 30 is pushed in the direction of the arrow. Then, with the optical fiber LF sandwiched between the pressing portion 30 and the second member 20, the pressing portion 30 and the second member 20 are moved together in the direction of the arrow. When the second member 20 reaches the second position (FIG. 3), the second member 20 and the pressing portion 30 are fixed to the pedestal portion 40. As a result, the optical fiber LF wound around the outer circumference of the winding core portion 110 can be made into an annular shape (kidney shape in the present embodiment) having curved irregularities (FIG. 2).

As described above, according to the optical fiber holder 100 of the present embodiment, the winding shape of the optical fiber LF can be easily formed into a so-called kidney-shaped annular shape having curved irregularities.

Further, according to the optical fiber holder 100, since the optical fiber LF can be fixed and held in an annular shape of the kidney shape, the reflection angle in the optical fiber LF is sequentially changed, and the excitation light causes the core of the clad fiber. It can easily pass through and be absorbed, and the output of the optical fiber LF can be improved.

Further, since the optical fiber LF is fixed in a wound state along the first arc portion 11 and the second arc portion 12 of the first member 10 and the substantially arc-shaped contact portion 34 of the pressing portion 30, the optical fiber LF is fixed. A predetermined curvature can be added according to the curvature of the 1 arc portion 11, the second arc portion 12, and the contact portion 34, and the optical fiber wound in an annular shape can be easily controlled to an appropriate curvature. Therefore, it is possible to suppress a decrease in the output of the optical fiber due to the small curvature.

According to the optical fiber holder 100 of the present embodiment, the optical fiber LF can be wound and held in a kidney shape having an appropriate curvature. Therefore, it is possible to improve the output of the optical fiber by using a general clad having a circular cross section without making the clad shape polygonal or twisting in the cross section orthogonal to the optical axis of the optical fiber. can. Further, since the curvature when winding the optical fiber can be reduced as compared with the case where a clad optical fiber having a polygonal cross section is used, the optical fiber holder 100 can be miniaturized.

Further, according to the optical fiber holder 100, since the optical fiber LF is fixed in a state of being wound around the kidney shape, it is easy to carry. Therefore, the optical fiber LF can be transported or sold in a state of being wound around the optical fiber holder 100.

According to the optical fiber holder 100, since the ratio of the first arc portion 11 to the second arc portion 12 is approximately 1: 3, cracking of the optical fiber LF and emission of excitation light can be appropriately suppressed. Can be done.

According to the optical fiber holder 100, the second member 20 and the pressing portion 30 can be moved on the same straight line at the same time with the optical fiber LF sandwiched between the second member 20 and the pressing portion 30. Therefore, it is possible to more stably and easily impart an appropriate curvature to the optical fiber.

According to the optical fiber holder 100, the first member 10, the second member 20, and the holding portion 50 are made of copper. Since copper has high thermal conductivity, the heat generated in the optical fiber LF can be released more efficiently. As a result, it is possible to suppress the occurrence of melting, optical destruction, spectrum change, etc. of the optical fiber LF.

<Second Embodiment>
FIG. 6 is an explanatory diagram showing a schematic configuration of the optical fiber holder 100A of the second embodiment. The optical fiber holder 100A of the present embodiment includes a cooling water flow path 18 as a cooling unit for cooling the optical fiber LF, in addition to the configuration of the optical fiber holder 100 of the first embodiment. In the embodiments described below, the same configurations as the optical fiber holder 100 are designated by the same reference numerals, and the preceding description will be referred to.

As shown in the figure, the first member 10A includes a cooling water flow path 18 inside. Known cooling water is circulated in the cooling water flow path 18 as shown by an arrow in the figure. In this way, the heat generated in the optical fiber LF can be released by heat exchange between the optical fiber and the cooling water. Therefore, the temperature rise of the optical fiber LF can be further suppressed.

<Modified example of this embodiment>
The present invention is not limited to the above-described embodiment, and can be implemented in various aspects without departing from the gist thereof. For example, the following modifications are also possible.

-The optical fiber holder does not have to include the pedestal portion 40 and the holding portion 50. For example, the winding core portion 110 and the pressing portion 30 may be directly attached to a device using an optical fiber such as an industrial laser machining machine.

The shapes of the first member 10, the second member 20, and the pressing portion 30 are not limited to the above-described embodiment. The first member 10 may be formed in a planar shape having a plurality of recesses. The number of arc portions is not limited to the above embodiment. An example is shown in FIG. However, in the optical fiber holder 100 of the above embodiment, it is easy to form the optical fiber LF in an annular shape having curved irregularities, and the first member 10 has a planar shape having a plurality of recesses. This is preferable because an output improvement effect that is substantially the same can be obtained.

FIG. 7 is an explanatory diagram showing a schematic configuration of the optical fiber holder 100C of the modified example. The optical fiber holder 100C includes a winding core portion 110C and two pressing portions 30. The winding core portion 110C includes a first member 10C and two second members 20C. The first member 10C has a planar shape having four first arc portions 11 having a first radius R1, a second arc portion 12 having two second radii R2, and two recesses 13C. In the modified example of the optical fiber holder 100C, the optical fiber LF is formed in an annular shape having curved irregularities.

The ratio of the first arc portion 11 to the second arc portion 12 in the first member 10 is not limited to the above embodiment.

The first member 10 may have a shape in which an arc and the arc are connected by a straight line. Further, the arc portion may be an elliptical arc.

The planar shape of the recess 13 of the first member 10 is not limited to the above embodiment. It is not necessary to provide the two parallel lines 14.

In the above embodiment, an example is shown in which the second member 20 is provided with the protrusion 22 and the pressing portion 30 is provided with the protrusion 32 so as to be movable along the groove 42 of the pedestal portion 40. The member 20 and the pressing portion 30 do not have to be provided with a protrusion. The second member 20 can move its straight line portion along the parallel line 14 of the recess 13 of the first member 10, and the pressing portion 30 pushes the outer peripheral portion 24 of the second member 20 to form an optical fiber. A dent can be added to the LF.

In the optical fiber holder 100 of the above embodiment, the second member 20 may be removed after the optical fiber LF is formed in a kidney shape. Even in this way, the optical fiber LF is pressed by the pressing portion 30, and the shape of the optical fiber LF can be maintained.

-The optical fiber holder 100 may further include a cooling unit such as a heat sink or a cooling fan.

-The material for forming each part of the optical fiber holder is not limited to the above embodiment, and various materials can be used.

Although the present invention has been described above based on the embodiments and modifications, the embodiments of the above-described embodiments are for facilitating the understanding of the present invention and do not limit the present invention. The present invention can be modified and improved without departing from the spirit and claims, and the present invention includes equivalents thereof. In addition, if the technical feature is not described as essential in the present specification, it may be deleted as appropriate.

10, 10A, 10C ... 1st member 11 ... 1st arc portion 12 ... 2nd arc portion 13, 13C ... recess 14 ... parallel line 18 ... cooling water flow path 20, 20C ... 2nd member 22, 32 ... protrusion 24 ... Outer peripheral part 30 ... Pressing part 34 ... Contact part 40 ... Pedestal part 42 ... Groove part 44 ... Screw hole 50 ... Holding part 100, 100A, 100C ... Optical fiber holder 110, 110C ... Winding core part LF ... Optical fiber P1 ... Most protruding Position R1 ... 1st radius R2 ... 2nd radius

Claims (6)

An optical fiber holder that winds and fixes an optical fiber.
A winding core in which the optical fiber is wound around its own circumference,
A pressing portion that presses the optical fiber wound around the outer periphery of the winding core portion toward the inside of the winding core portion, and the planar shape of the contact portion that comes into contact with the optical fiber is substantially arcuate. When,
With
The winding core is
A flat plate-shaped first member having a plurality of substantially arc-shaped arc portions and at least one recess.
A first position in which at least a part of itself is arranged in the recess and the optical fiber wound around the winding core portion is formed into a substantially annular shape, and the optical fiber wound around the outer circumference of the winding core portion. A second member that is movable to a second position that has curved irregularities to form an annular shape, and a second member that has a substantially arcuate planar shape of the outer peripheral portion that is the outer periphery of the winding core portion. ,
With
The pressing portion is fixed in a state where the optical fiber is pressed toward the recess of the first member.
Fiber optic holder. The optical fiber holder according to claim 1.
The first member has a diameter larger than that of the first arc portion, which is connected to one recess, two first arc portions arranged on both sides of the recess, and ends of the two first arc portions. It is a planar shape composed of two arcs.
Fiber optic holder. The optical fiber holder according to claim 2.
The ratio of the first arc portion to the second arc portion is approximately 1: 3.
Fiber optic holder. The optical fiber holder according to any one of claims 1 to 3.
The recess of the first member has a planar shape having two parallel lines.
The second member and the pressing portion are configured to be movable along the two parallel lines of the recess.
Fiber optic holder. The optical fiber holder according to any one of claims 1 to 4.
A cooling unit for cooling the optical fiber is provided.
Fiber optic holder. The optical fiber holder according to any one of claims 1 to 5.
The outer peripheral surface of the first member is made of a metal having high thermal conductivity.
Fiber optic holder.

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