JP4134500B2 - Optical fiber cable manufacturing method and manufacturing apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method and an apparatus for manufacturing an optical fiber cable in which a plurality of optical fiber cores are twisted and a fiber material is twisted around the core.
[0002]
[Prior art]
When a self-supporting optical fiber cable in which a support line and a cable body are integrated by a sheath is suspended in an aerial space, the cable body is held by fixing both ends of the support line to a power pole. The advantage of this cable is that the support wire and the cable main body are integrated, so that it is not necessary to negotiate the support wire alone, and the work efficiency is such that only one negotiation work is required. However, when the self-supporting optical fiber cable is suspended, the tension applied to the support line is several hundred kgf, and the elongation is about 0.2%. It is a big problem from the viewpoint of long-term reliability that an elongation of about 0.2% is constantly applied to the optical fiber core.
[0003]
An example of a self-supporting optical fiber cable that solves this problem is shown in FIGS. In the figure, 1 is a support wire, 2 is a cable body, 3a and 3b are sheaths, 3c is a neck portion, 4 is a slit, 5 is a support wire portion, and 6 is a cable body portion. In this self-supporting optical fiber cable, the support wire 1 and the cable body 2 are integrally covered and connected by a common sheath. In other words, the support wire portion 5 in which the support wire 1 is covered with the sheath 3a and the cable body portion 6 in which the cable main body 2 is covered with the sheath 3b are connected by the neck portion 3c integrated with the sheaths 3a and 3b. The outer diameter of the optical fiber main body 6 is usually larger than the outer diameter of the support wire portion 5, and therefore the common sheath is a saddle-shaped sheath. Slits 4 are intermittently formed in the neck 3c of the saddle type sheath. In FIG. 4, the self-supporting optical fiber cable is installed and stretched by applying tension to the support wire 1, and the cable body 2 is parallel to the support wire 5. In a state where no tension is applied to the support wire 1, the cable body 6 has an extra length with respect to the support wire portion 5 as shown in FIG. 5. The main body portion 6 meanders with respect to the support wire portion 5.
[0004]
There is an optical fiber assembly at the center of the cable body of the self-supporting optical fiber cable with the saddle-shaped sheath, and the outside is completely covered with a cushioning filler of a plurality of fiber materials used as a protective material. However, there is known one using an optical fiber cable provided with a sheath on the outside thereof.
[0005]
FIG. 7 is a cross-sectional view of an example of a self-supporting optical fiber cable using such a fiber material as a protective material. In the figure, the same parts as those in FIGS. 2a is a tape-shaped optical fiber, 2b is a fiber material, 7 is a steel wire, and 8 is a tear string. In this example, an assembly of a plurality of tape-shaped optical fibers 2a is used as an optical fiber assembly. The assembled tape-shaped optical fiber 2a is twisted and provided in a swiveled state, and the fiber material 2b is provided so as to be twisted around the assembled tape-shaped optical fiber 2a. Yes. The steel wire 7 is provided to prevent the cable body 6 from contracting. When a compression force is applied to the cable body 6, the steel wire 7 is suspended by the elasticity of the steel wire 7 disposed above and below. The cable body 6 meanders in the left-right direction, and local bending can be avoided, but the steel wire 7 does not act as a tensile wire that can resist the support wire. In addition, there is a case where the tear string 8 is not provided.
[0006]
The optical fiber cable having the cable body as described in FIG. 7 and having the sheath provided thereon is assembled by twisting the fiber material and twisting the fiber material, and then winding the sheath once. Generally, the process is shifted to a coating process, and the sheath is applied in a process separate from the process of assembling the optical fiber core wires. The quality problem in such a conventional manufacturing method is that the fiber material becomes non-uniform around the assembly of optical fibers, and the optical fiber inside may jump out of the fiber material. Even if it does not jump out, it is difficult to provide the fiber material uniformly because the fiber material is biased and the sheath does not become a clean circle. The disordered arrangement of the fiber material may cause harmful distortion to the optical fiber, and the difference in the elongation of the fiber material may cause uneven stretching in the longitudinal direction, resulting in an increase in loss.
[0007]
Even in the manufacturing method in which the process of assembling the optical fiber and the process of twisting the fiber material are performed in one step, and further in the manufacturing method in which the entire process is performed in one step continuously until the step of covering the sheath, the collected light If the assembled optical fibers are scattered before entering the step of twisting the fiber material on the fiber, there is a problem that the fiber material cannot be twisted uniformly.
[0008]
The optical fiber and the fiber material are twisted together by a rotating cage. However, when the optical fiber and the fiber material are arranged in the same cage, the twisting pitch and the twisting direction of the optical fiber and the fiber material are always the same. When the fiber material cage is placed in front of the optical fiber twisting cage, there is a long distance from twisting the optical fiber to twisting the fiber material, which may cause optical fiber misalignment or trauma. There is.
[0009]
[Problems to be solved by the invention]
The present invention has been made in view of the above-described circumstances, and the assembled optical fiber cores are scattered before entering the step of twisting the fiber material onto the optical fiber cores assembled in the assembly process. It is an object of the present invention to provide an optical fiber cable manufacturing method and manufacturing apparatus that can prevent the occurrence of damage, disorder of arrangement, and damage.
[0010]
[Means for Solving the Problems]
According to the first aspect of the present invention, a plurality of optical fiber cores are assembled to form an optical fiber core assembly, and a sheath is attached to a cable body in which fiber materials are assembled around the optical fiber core assembly. a method of manufacturing a coated optical fiber cables, in close proximity to the traveling direction of the optical fiber assembly of the set point of the optical fiber is arranged a set point of the fiber material, assembled with the fiber material In a method of manufacturing an optical fiber cable in which a cable body is supplied to an extruder in a substantially straight state to continuously cover a sheath, a distance between an assembly point of the optical fiber core wires and an assembly point of the fiber material is 0.1 m. As mentioned above, it is 1.5 m or less .
[0012]
According to a second aspect of the present invention, in the method for manufacturing an optical fiber cable according to the first aspect , the fiber material has a direction of the fiber material coming from a supply source and a traveling direction of the optical fiber core assembly. An angle of about 90 ° or less is supplied in a direction opposite to the traveling direction of the optical fiber core assembly, and the optical fiber core assembly is provided before the assembly point of the fiber material. The traveling direction is changed toward the traveling direction, and the assembly is performed.
[0013]
According to a third aspect of the present invention, an optical fiber core assembly is formed by assembling a plurality of optical fiber cores, and a sheath is attached to a cable body in which fiber materials are assembled around the optical fiber core assembly. an apparatus for producing a coated optical fiber cable, a set guide or collectively die in proximity to the traveling direction of the optical fiber assembly of the set guide or collection die to assemble the optical fiber is set fiber material And an assembly guide for assembling the optical fiber cores in an apparatus for manufacturing an optical fiber cable in which an extruder is disposed so as to continuously cover the sheath of the cable body in which the fiber materials are assembled in a substantially straight state. or the distance between the set guide or collection die to assemble a set die the fiber material 0.1m or more, to wherein a is 1.5m or less It is intended.
[0015]
According to a fourth aspect of the present invention, in the optical fiber cable manufacturing apparatus according to the third aspect , the fiber material has a direction of the fiber material coming from the supply source and a traveling direction of the optical fiber core assembly. An angle of about 90 ° or less is supplied in a direction opposite to the traveling direction of the optical fiber core assembly, and the optical fiber core assembly is provided before the assembly point of the fiber material. The traveling direction is changed toward the traveling direction, and the fiber material is introduced into a collecting guide or a collecting die that collects the fiber materials.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
1 and 2 are explanatory views of a production line for explaining an embodiment in which the method for producing an optical fiber cable of the present invention is applied to the production of a self-supporting type optical fiber cable. FIG. 3 is a diagram in which one figure connected at point A in FIG. 2 is divided. In the figure, 10 is an optical fiber core, 11 is an optical fiber core supply reel, 12 is an optical fiber core assembly, 13 is a fiber material supply reel, 14 is a fiber material, 15 is a guide roller, 16 is a cable body, 17 is a coarsely wound yarn, 18 is a steel wire supply reel, 19 is a steel wire, 20 is a support wire supply reel, 21 is a support wire, 22 is an extruder, 23 is a crosshead, 24 is a self-supporting optical fiber cable, 25 Is a cooling water tank, 26 is a take-up capstan, and 27 is a winding device. This manufacturing line will be described on the assumption that the self-supporting optical fiber cable described in FIG. 7 is manufactured.
[0017]
The optical fiber cores 10 are supplied from an optical fiber core supply reel 11 provided on the rotating cage, and are assembled while being turned and twisted to form an optical fiber core assembly 12. In this example, ten tape-shaped optical fiber cores are assembled using a tape-shaped optical fiber core as the optical fiber core 10, but depending on the number of tape-shaped optical fiber cores to be assembled and the aggregate shape. Thus, the tape-shaped optical fiber cores may be assembled in two stages, or may be assembled in three or more stages. In the present invention, the optical fiber core wire is not limited to a tape-shaped optical fiber core wire, and a single optical fiber core wire may be used. A fiber body 14 forming a cushion layer supplied from a fiber material supply reel 13 provided on a rotating cage is twisted on the optical fiber core assembly 12 to form a cable body 16. One fiber material supply reel 13 supplies one or a plurality of fiber materials. As the fiber material 14, polypropylene fiber is used, but is not limited thereto. In addition, the fiber material may be a single fiber or a single fiber twisted into a thread. As will be described later, the direction of the fiber material 14 is changed by a grooved guide roller 15 provided on the rotating cage, and the fiber material 14 is twisted together with the optical fiber assembly 12. Instead of the guide roller 15, any member that can change the traveling direction of the fiber material 14, such as a non-rotating pin member, may be used. The twisting direction of the fiber material 14 is twisted in the same direction with respect to the turning direction of the optical fiber assembly 12. The twisting direction of the fiber material 14 may be opposite to the turning direction of the optical fiber assembly 12. The twisting pitch of the fiber material 14 is the same as the turning pitch of the optical fiber assembly 12, or the twisting pitch of the fiber material 14 is set with respect to the turning pitch of the optical fiber assembly 12. A method of using a large pitch or a small pitch can be employed. By twisting the fiber material 14 as described above, the fiber material 14 does not bite into the optical fiber assembly 12, a protective layer is formed, and the aggregate state of the optical fiber assembly 12 is broken. It can be prevented from becoming distracted. The cable body 16 is bound with a coarsely wound yarn 17 such as a nylon yarn in the next step as necessary.
[0018]
The cable body 16 thus formed is guided to the cross head 23 of the extruder 22 while maintaining a straight state. A steel wire 19 and a support wire 21 to be inserted into the sheath portion of the cable body 16 are simultaneously introduced into the cross head 23. The steel wire 19 is a single wire having a diameter of about 0.4 to 1.0 mm, for example, and is provided to reduce the compressive strain applied to the cable body 16. Supplied from the steel wire supply reel 18 and introduced into the crosshead 23. The support line 21 is supplied from the supply line supply reel 20, is pre-tensioned, and is introduced into the cross head 23.
[0019]
In the cross head 23 into which the cable body 16, the steel wire 19, and the support wire 21 are introduced, a common sheath is made of thermoplastic resin or the like, and slits are intermittently formed as described with reference to FIGS. Thus, a self-supporting optical fiber cable 24 having a saddle-shaped cross section is completed. After exiting the crosshead 23, the common sheath is not cured, cooled through the cooling water tank 25, taken up by the take-up capstan 26, and taken up by the take-up device 27.
[0020]
In this way, the optical fiber core and the fiber material were assembled and guided to the sheath extruder as it was. Moreover, during this time, the straight state was maintained without wrapping around the roller. Note that the straight state does not necessarily have to be a straight line and may have some bends, but if there is a bend, the bend radius needs to be 2 m or more. Therefore, the straight state in the present specification means a bent state having a bending radius of 2 m or more. Of course, it is natural that a straight line having an infinite bending radius is included. Rather, a straight line is desirable.
[0021]
After the sheath is applied in a straight state, it is cooled, taken up and wound up. Therefore, unlike the conventional case, the optical fiber core and the fiber material are gathered, and then wound up once and then pulled out again, so that the surrounding of the fiber material is not disturbed and the arrangement is not disturbed.
[0022]
In this way, the fiber material is twisted on the assembled optical fiber core wires in the next step. In this case, even if the assembled state of the assembled optical fiber cores may be slightly collapsed if the distance from the assembly position of the assembled optical fiber cores to the position where the fiber material is twisted is large, the fiber material It was found that the surroundings were uneven and the fiber material could not be twisted together.
[0023]
Therefore, in the present invention, the assembly of the fiber material is performed immediately after the assembly of the optical fiber core wires. That is, the fiber material assembly point is arranged in the vicinity of the twisted assembly point of the optical fiber core wires (on the traveling direction side of the optical fiber assembly).
[0024]
Since the assembly of the fiber material and the assembly of the optical fiber cores are respectively performed using a rotating cage, there is a limit in bringing the assembly point of the fiber material and the assembly point of the optical fiber core wires close to each other.
[0025]
As described with reference to FIG. 1, the fiber material 14 is changed in direction by a guide roller 15 with grooves provided on the rotating cage and twisted to the optical fiber assembly 12, thereby collecting the fiber material. It is easy to bring the point immediately after the set point of the optical fiber core wires.
[0026]
FIG. 3 is an explanatory diagram of a method for assembling a fiber material aggregation point and an optical fiber core wire. In the figure, the same parts as those in FIG. The optical fiber cores 10 are assembled at point P. At the point P, the optical fiber core wires 10 are assembled along the side surface of the virtual conical body. Call a half of the angular theta ₁ of the apex angle of the imaginary cone bodies collectively angle for theta _1, when theta ₁ is greater than 45 °, trauma to the optical fiber by the guide and a die for use in the set Therefore, θ ₁ is preferably set to 45 ° or less.
[0027]
The fiber material 14 is assembled so as to be twisted to the optical fiber core assembly 12 at a point Q in front of the point P. The fiber material 14 is also guided to the point Q along the side surface of the virtual cone. It is preferable that the angle θ ₂ ½ of the apex angle of the virtual cone is 45 ° or less. If θ ₂ exceeds 45 °, the fiber material 14 tends to clamp the optical fiber core assembly 12, which causes a problem of increasing the loss of the optical fiber core assembly 12.
[0028]
As described above, in order to reduce the distance L between the point P and the point Q, the fiber material 14 is guided to the point Q so that the direction is changed by the guide roller 15. The angle θ between the path line from the first to the guide roller 15 that is the direction change point and the traveling direction of the optical fiber core assembly 12 is preferably about 90 ° or less. That is, the angle θ formed by the traveling direction of the fiber material 14 coming out of the fiber material supply reel 13 and the optical fiber core assembly 12 is preferably about 90 ° or less. When the angle exceeds 90 °, the rotation cage loaded with the fiber material supply reel 13 is arranged so as not to interfere with the rotation cage loaded with the optical fiber core supply reel 11, and the point Q is brought close to the point P. Because it will not be possible. The fiber material 14 coming out of the fiber material supply reel 13 at this angle θ is changed in direction to the traveling direction side of the optical fiber core assembly 12 by the guide roller 15 and becomes the optical fiber core assembly 12 at the point Q. Assembled. If the distance L between the point P, which is the assembly point of the optical fiber cores 10, and the point Q, which is the twist point of the fiber material 14, is large, the fiber cores may be scattered before the fiber material 14 is twisted together. , Some core wires may sag and cause a jump rope phenomenon. Therefore, the Q point is brought close to the P point. By bringing the Q point close to the P point, the fiber material 14 can be assembled in a state where the optical fiber cores are aligned and twisted. As a specific range to be close, if the distance L between the point P and the point Q is smaller than 0.1 m, there is a problem in the setting work, and if it exceeds 1.5 m, the twisted optical fiber cores are broken. Therefore, it is preferable to set the distance to 0.1 m or more and 1.5 m or less.
[0029]
Note that when the optical fiber cores are assembled at a plurality of stages of gathering positions, the last stage gathering position corresponds to the point P.
[0030]
In the above-described embodiments, the self-supporting optical fiber cable has been described. However, the present invention is not limited to the self-supporting optical fiber cable, and a plurality of optical fiber cores are twisted together and their surroundings are arranged. An optical fiber cable that collects a plurality of optical fiber cables in which fiber materials are twisted together, and an optical fiber cable that is sheathed thereon, or an optical fiber cable that collects a plurality of them around a tensile body The present invention can be applied to an optical fiber cable having an appropriate structure.
[0031]
As described above, the present invention enters the step of twisting the fiber material on the optical fiber cores assembled in the assembly process because the assembly point of the optical fiber cores and the assembly point of the fiber materials are close to each other. It is possible to prevent the assembled optical fiber cores from being scattered before, and further, it is possible to perform these in a straight line and a single process including the process of applying the sheath, thereby reducing the cost. It is possible to manufacture an optical fiber cable that can be reduced and manufactured under suitable conditions to maintain good and stable quality.
[0032]
【The invention's effect】
As is apparent from the above description, according to the invention described in claim 1 or 3 , the arrangement of the optical fiber core wires and the disturbance of the pitch can be prevented, and the fiber material is twisted in a state where the cross-sectional arrangement is stable. be able to.
[0033]
According to invention of Claim 2 or 4 , it becomes easy to arrange | position the gathering point of a fiber material in the distance of 0.1 m or more and 1.5 m or less ahead of the twisting gathering point of an optical fiber core wire. There is an effect.
[Brief description of the drawings]
FIG. 1 is an explanatory view of a part of a production line for explaining an embodiment in which the method for producing an optical fiber cable of the present invention is applied to the production of a self-supporting optical fiber cable.
FIG. 2 is an explanatory view of a part of a production line for explaining an embodiment in which the method for producing an optical fiber cable of the present invention is applied to the production of a self-supporting optical fiber cable.
FIG. 3 is an explanatory diagram of a method of assembling fiber material assembly points and optical fiber core wires.
FIG. 4 is a perspective view for explaining an example of a self-supporting optical fiber cable.
FIG. 5 is a perspective view for explaining an example of a self-supporting optical fiber cable.
FIG. 6 is an explanatory diagram of an example of a self-supporting optical fiber cable.
FIG. 7 is a cross-sectional view of an example of a self-supporting optical fiber cable.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Support wire, 2 ... Cable main body, 2a ... Tape-shaped optical fiber core wire, 2b ... Fiber material, 3a, 3b ... Sheath, 3c ... Neck part, 4 ... Slit, 5 ... Support line part, 6 ... Cable main-body part, DESCRIPTION OF SYMBOLS 7 ... Steel wire, 8 ... Tear string, 10 ... Optical fiber core wire, 11 ... Optical fiber core wire supply reel, 12 ... Optical fiber core wire assembly, 13 ... Fiber material supply reel, 14 ... Fiber material, 15 ... Guide Roller, 16 ... Cable body, 17 ... Coarse winding yarn, 18 ... Steel wire supply reel, 19 ... Steel wire, 20 ... Support wire supply reel, 21 ... Support wire, 22 ... Extruder, 23 ... Crosshead, 24 ... Self Support type optical fiber cable, 25 ... cooling water tank, 26 ... take-up capstan, 27 ... winding device.

Claims (4)

An optical fiber cable manufacturing method in which a plurality of optical fiber cores are assembled to form an optical fiber core assembly, and a fiber body is assembled around the optical fiber core assembly to cover a cable body with a sheath. The fiber material assembly point is arranged on the traveling direction side of the optical fiber core assembly with respect to the assembly point of the optical fiber cores, and the cable body assembled with the fiber material is supplied to the extruder in a substantially straight state. In the manufacturing method of the optical fiber cable which coat | covers a sheath continuously,
A method of manufacturing an optical fiber cable, wherein a distance between an aggregation point of the optical fiber cores and an aggregation point of the fiber material is 0.1 m or more and 1.5 m or less. The fiber material has a traveling direction of the optical fiber core assembly at an angle of 90 ° or less between the direction of the fiber material coming from the supply source and the traveling direction of the optical fiber core assembly. It is fed in a direction retrograde with claim 1, wherein from the front of the set point of the fiber material, characterized in that it is set is changed the traveling direction toward the traveling direction of the optical fiber assembly The manufacturing method of the optical fiber cable as described in any one of. An optical fiber cable manufacturing apparatus in which a plurality of optical fiber cores are assembled to form an optical fiber core assembly, and a fiber body is assembled around the optical fiber core assembly to cover a cable body with a sheath. The assembly guide or assembly die for assembling the fiber material is arranged on the traveling direction side of the assembly of the optical fiber core wires of the assembly guide or assembly die for assembling the optical fiber core wires, and the cable is formed by assembling the fiber materials. In an optical fiber cable manufacturing apparatus in which an extruder is arranged so as to continuously cover a sheath in a substantially straight state,
Manufacturing of an optical fiber cable, wherein a distance between an assembly guide or assembly die for assembling the optical fiber core wires and an assembly guide or assembly die for assembling the fiber material is 0.1 m or more and 1.5 m or less apparatus. The fiber material has a traveling direction of the optical fiber core assembly at an angle of 90 ° or less between the direction of the fiber material coming from the supply source and the traveling direction of the optical fiber core assembly. And a collecting guide or a collecting die for collecting the fiber material by changing the traveling direction from the front of the assembly point of the fiber material toward the traveling direction of the optical fiber core assembly. The optical fiber cable manufacturing apparatus according to claim 3 , wherein the optical fiber cable manufacturing apparatus is introduced into the optical fiber cable.

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