JP2004078032A - Optical fiber cable and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical fiber cable which is small in a diameter, improves a loss characteristic and is excellent in workability, and to provide its manufacturing method. <P>SOLUTION: This optical fiber cable is composed of a long-length optical element part 11 that covers with a cable sheath an optical fiber core wire 3 consisting of a single or a plurality of wires or coated optical fiber tapes, an intervention body 5 that collectively and roughly winds all of the optical fiber core wires 3, and tension bodies 7 for optical elements arranged parallelly at both sides near the intervention body 5. Notch parts 13 are formed on the surface of the cable sheath 9 at both sides of the intervention body 5 perpendicularly to the direction of connecting the respective tension bodies 7 for optical elements. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a multi-core drawn optical fiber cable and a method of manufacturing the same.
[0002]
[Prior art]
A drop-down optical fiber cable (drop cable) for premises and overhead is usually one or two cores, but with the expansion of FTTH (Fiber to the Home), about four to ten cores are used for small condominiums and buildings. Demand for multi-core is expected.
[0003]
Also, from the viewpoint of the post-branching workability, it is considered that an optical fiber core using a single strand (or a tape optical fiber core of about two cores) is effective.
[0004]
When designing a multi-core pull-down optical fiber cable containing a single optical fiber core wire, a loose tube cable or a slot cable can be considered, but all of them have a large outer diameter and are costly. The cable that follows the small-diameter simple indoor cable 101 as shown in FIG. That is, in FIG. 7, a drop-indoor cable 101 is a single-core optical fiber core fiber 103 and a tensile sheath 105 for an optical element arranged in parallel and on both sides in the vicinity thereof with a cable sheath 107. A notch 109 is formed on the surface of the cable sheath 107 on both sides (up and down in FIG. 7) of the optical fiber core 103 in a direction perpendicular to the direction in which the tensile elements 105 for the optical elements are connected. It is a thing.
[0005]
[Problems to be solved by the invention]
However, as shown in FIG. 8, when it is attempted to accommodate a multi-core wire 111 instead of a single-core optical fiber core wire 103 in the drop indoor cable 101, a plurality of wires 111 are connected. If a bundle is formed and the sheath is made solid, the sheath material 107 bites into the inside, and there is a problem in the opening property.
[0006]
On the other hand, as shown in FIG. 9, when the multi-filamentary wire 111 is put into a pipe connected to the through hole of the nipple in the extrusion head and extruded from the pipe, it becomes squashed, so that the optical fiber May move in the cable (the optical fiber core may be bent and the loss may increase in the closure). Furthermore, it is conceivable to provide a cushion layer around the multicore as an intervening body for preventing movement of the fiber, for example, but since the fiber is scattered, the cable tends to meander when the cable contracts at a low temperature, resulting in an increase in loss. There are concerns that may arise.
[0007]
The present invention has been made to solve the above-described problems, and an object of the present invention is to provide an optical fiber cable having a small diameter and improving loss characteristics, and having excellent workability, and a method of manufacturing the same. .
[0008]
[Means for Solving the Problems]
In order to achieve the above object, an optical fiber cable according to the present invention according to claim 1 comprises an optical fiber core consisting of one or more strands or a tape core, and all of the optical fiber cores collectively wound together. And a long optical element portion covered by a cable sheath with an optical element strength member disposed in parallel on both sides in the vicinity of the intermediate body, and tying the optical element strength members together. A notch is formed on the surface of the cable sheath on both sides of the intervening body in a direction perpendicular to the direction of the elbow.
[0009]
Therefore, when the cable sheath is torn out from the notch portion to output the optical fiber core, the cable sheath is blocked by the intervening body and does not bite into the optical fiber core, so that the output is easily performed. In addition, the loss characteristic is stabilized because it is manufactured with a small diameter and an intervening body such as a fiber serves as a cushion for the optical fiber core. In addition, since all of the optical fiber cores are collectively wound by the intervening body, all of the optical fiber cores are firmly integrated. Moreover, since all of the optical fiber cores are integrated, the bending rigidity is increased, and the meandering of the optical fiber core due to contraction of the cable at low temperatures is less likely to occur. Further, the optical fiber cable is simplified, there is no assembly process, and the processing cost is reduced.
[0010]
According to a second aspect of the present invention, there is provided the optical fiber cable according to the first aspect, wherein a long cable support wire portion having a support wire covered with a sheath is integrated in parallel with the optical element portion. It is characterized by having.
[0011]
Therefore, the optical element portion is used as an optical fiber drop cable by integrating a long cable support wire portion in which a support wire is covered with a sheath in parallel with each other. Has an action.
[0012]
According to a third aspect of the present invention, in the optical fiber cable according to the first or second aspect, a coarse winding tension when the intermediate body is roughly wound around all of the optical fiber core wires at a time is 490 mN or more. 4900 mN or less, and the pitch is 10 mm or more and 1000 mm or less.
[0013]
Therefore, if the tension of the coarse winding is too large, side pressure and bending are applied to the optical fiber, and there is a concern that the loss may increase. Is desirable. If the winding pitch is too small, the productivity is poor, and if the winding pitch is too large, the optical fiber is not integrated, so that a pitch of 10 mm or more and 1000 mm or less is desirable.
[0014]
According to a fourth aspect of the present invention, there is provided a method for manufacturing an optical fiber cable, comprising: an optical fiber core comprising one or a plurality of strands or a tape; The optical element strength members arranged in parallel on both sides in the vicinity of the intervening body are respectively run and supplied to the extruder, and the thermoplastic resin is extruded into the extruder, and one or more strands or An optical fiber core consisting of a taped optical fiber, an interposer in which all of the optical fibers are roughly wound together, and a tensile element for an optical element which is arranged near both sides of the intermediary in parallel. Of the cable sheath on both sides of the intervening body in a direction perpendicular to the direction in which the optical element strength members are connected. It is characterized in that for manufacturing an optical fiber cable to form a notch in the surface.
[0015]
Therefore, in the same manner as in claim 1, when the cable sheath is torn out from the notch portion and the optical fiber core is led out, the cable sheath is blocked by the intervening body and does not bite into the optical fiber core. Done. Further, the loss characteristics are stabilized because the intermediate body is manufactured to have a small diameter and the intermediate body serves as a cushion for the optical fiber core. In addition, since all of the optical fiber cores are collectively wound by the intervening body, all of the optical fiber cores are firmly integrated. Moreover, since all of the optical fiber cores are integrated, the bending rigidity is increased, and the meandering of the optical fiber core due to contraction of the cable at low temperatures is less likely to occur. Further, the optical fiber cable is simplified, there is no assembly process, and the processing cost is reduced.
[0016]
According to a fifth aspect of the present invention, there is provided a method for manufacturing an optical fiber cable, comprising: an optical fiber core comprising one or a plurality of strands or a tape; An optical element tensile strength member arranged in parallel on both sides in the vicinity of the intervening member, and a support wire is respectively run and supplied to an extrusion head, and a thermoplastic resin is extruded to the extrusion head, and one or more An optical fiber core consisting of an element wire or a tape optical fiber core, an intervening body that is roughly wound around all of the optical fiber cores, and an optical element disposed near and parallel to both sides of the intervening body And a lengthwise optical element portion covered with a cable sheath, and both sides of the interposition member in a direction perpendicular to a direction in which the respective tensile strength members for optical elements are connected. Forming a notch portion on the surface of the cable sheath in the optical element portion, and manufacturing an optical fiber cable in which a long cable support wire portion having a support wire covered with a sheath is integrated in parallel with each other on the optical element portion. Is what you do.
[0017]
Therefore, the optical element portion is used as an optical fiber drop cable by integrating a long cable support wire portion in which a support wire is covered with a sheath in parallel with each other. Has an action.
[0018]
According to a sixth aspect of the present invention, in the method for manufacturing an optical fiber cable according to the fourth or fifth aspect, when the intervening body is supplied to an extruder, the intermediate body is bundled with all of the optical fiber cores. It is characterized by being roughly wound.
[0019]
Therefore, when the intervening body is supplied to the extruder, the optical fiber cable is continuously and rationally manufactured because the intermediate fiber is roughly wound around all of the optical fiber core wires.
[0020]
According to a seventh aspect of the present invention, in the method for manufacturing an optical fiber cable according to the fourth, fifth or sixth aspect, the intermediate body is roughly wound around all of the optical fiber cores. Is characterized by having a coarse winding tension of 490 mN or more and 4900 mN or less and a pitch of 10 mm or more and 1000 mm or less.
[0021]
Therefore, if the tension of the coarse winding is too large, side pressure and bending may be applied to the optical fiber, and there is a concern that the loss may increase. Is desirable. When the winding pitch is too small, the productivity is poor, and when the winding pitch is too large, the optical fiber is not integrated, so that a pitch of 10 mm or more and 1000 mm or less is desirable.
[0022]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0023]
Referring to FIG. 1, an optical fiber cable 1 according to an embodiment of the present invention includes an optical fiber core 3 made up of a plurality of, for example, eight strands. Then, it is roughly wound with an intervening body 5 made of, for example, an organic fiber or an inorganic fiber. In the vicinity of the intervening member 5, the optical element tensile strength members 7 are arranged on both sides in parallel. The optical fiber 3, the intervening body 5, and the optical element strength member 7 are covered with a cable sheath 9 made of a thermoplastic resin, and comprise an elongated optical element portion 11. Notch portions 13 are formed on the surface of the cable sheath 9 on both sides (up and down) of the intervening body 5 in a direction (up and down direction in FIG. 1) orthogonal to the direction connecting the optical element tensile strength members 7. I have.
[0024]
With the above configuration, when the cable sheath 9 is torn out from the notch portion 13 to output the optical fiber core 3, the cable sheath 9 is prevented by the intervening body 5 and does not bite into the optical fiber core 3, so that the cable sheath 9 is easily output. It can be performed. In addition, since the intermediate body 5 is manufactured to have a small diameter and the intermediate body 5 such as a fiber serves as a cushion for the optical fiber core 3, the loss characteristics can be stabilized. In addition, since all of the optical fiber cores 3 are collectively roughly wound by the intervening body 5, all of the optical fiber cores 3 can be firmly integrated. In addition, since all of the optical fiber cores 3 are integrated, the bending rigidity can be increased, and the meandering of the optical fiber core 3 due to contraction of the cable at a low temperature can be suppressed. Further, the optical fiber cable becomes simple, there is no assembly step, and the processing cost can be reduced.
[0025]
Referring to FIG. 2, another optical fiber cable 1 according to the embodiment of the present invention includes an optical fiber core 3 made up of a plurality of, for example, eight strands, like the one shown in FIG. All of the optical fiber core wires 3 are collectively wound by an intervening body 5 made of, for example, an organic fiber or an inorganic fiber. In the vicinity of the intervening member 5, the optical element tensile strength members 7 are arranged on both sides in parallel. The optical fiber 3, the intervening body 5, and the optical element strength member 7 are covered with a cable sheath 9 made of a thermoplastic resin, and comprise an elongated optical element portion 11. Notches 13 are formed on the surface of the cable sheath 9 on both sides (up and down) of the intervening body 5 in a direction (vertical direction in FIG. 2) orthogonal to the direction in which the tensile elements 7 for optical elements are connected. I have. Further, a long cable support wire portion 19 in which a support wire 15 made of, for example, a steel wire is covered with a sheath 17 is integrated with the optical element portion 11 via a neck portion 21 in parallel with each other.
[0026]
With the above-described configuration, the long cable support wire portions 19 in which the support wires 15 are covered with the sheath 17 are integrated with the optical element portion 11 in parallel with each other via the neck portion 21, so that the optical fiber drop cable 1 is formed. And has the same effect as the effect in FIG.
[0027]
The optical fiber core 3 may use a single strand or a tape core in addition to a plurality of strands. In particular, a strand of 0.25 mmφ is most preferably used, but a two-core tape or a single core of about 0.4 to 0.9 mmφ is also used. As the organic fiber or the inorganic fiber as the intervening body 5, for example, heat-resistant plastic yarn such as nylon or PP, Kevlar fiber, glass wool, or cotton yarn is preferably used. Further, as the tensile element 7 for the optical element, a steel wire or FRP is preferably used, and a steel wire is used for the support wire 15.
[0028]
Next, a method for manufacturing an optical fiber cable will be described.
[0029]
FIG. 3 shows a method of manufacturing the optical fiber 1 shown in FIG. In FIG. 3, an optical fiber core wire 3 composed of, for example, eight strands runs from left to right, and an intervening body 5 composed of, for example, a plurality of aramid fibers wound on a bobbin (not shown) is used as a bobbin. By being rotated around the optical fiber 3 as indicated by the arrow, it is roughly wound around the optical fiber 3. The optical fiber core wire 3 roughly wound by the intermediate body 5 made of the plurality of aramid fibers, the two tensile strength members 7 for the optical element, and the support wire 15 made of, for example, a steel wire are run and sent to the extruder 23. Can be In this extruder 23, an optical fiber drop cable as the optical fiber cable 1 can be obtained by extruding the thermoplastic resin to be the cable sheath 9 and the sheath 17 from another hole.
[0030]
More specifically, FIG. 4 shows a cross-sectional view of the extrusion head 25 of the extruder 23. In FIG. 4, a nipple portion 27 as shown in FIG. 5 is provided at the center, and a die hole 29 and this die as shown in FIG. A die portion 35 having a die hole 33 is provided in the hole 29 via the connection hole 31. A hole 37 through which a thermoplastic resin as a sheath is extruded is provided between the die portion 35 and the nipple portion 27. As shown in FIG. 5, the nipple portion 27 has a nipple hole 39 through which the intervening body 5 in which the optical fiber 3 is collectively wound is provided. A nipple hole 41 through which the tensile strength member 7 passes is formed. A pipe 43 is connected to the front of the nipple hole 39 (to the left in FIG. 5).
[0031]
According to the above configuration, the intermediate body 5 in which the optical fiber core wire 3 is roughly wound around the nipple hole 39 and the pipe 43 collectively, the tensile strength member 7 for an optical element passes through the nipple hole 41, and the die hole 33 has a support. As indicated by the line 17, the molten thermoplastic resin P is extruded from the hole 37 of the die portion 35, and an optical fiber drop cable as the optical fiber cable 1 as shown in FIG. 2 can be obtained. Also, by using another die, the optical fiber cable 1 as shown in FIG. 1 can be obtained.
[0032]
(Example 1)
The optical fiber core wire 3 is a 0.25 mm φ SM wire, an eight-colored dye wire, and the aramid fiber (Kepra) 1140 denier 3 is used as the interposer 5 wound around the wire. The wire was wound around the eight optical fiber core wires 3. A 0.4 mmφ steel wire is used as the tensile element 7 for the optical element, a 1.2 mmφ steel wire is used as the support wire 15, and a flame-retardant polyethylene is used as the sheaths 9 and 17. did. At this time, the wire was roughly wound around the eight-core dyeing line with an intervening body 5 made of 380 denier aramid fiber. When the cross section of the cable after the extrusion was observed, the resin firmly wrapped the eight optical fiber core wires 3 roughly wound by the fibers of the intervening body 5 and had a very small diameter of 2 mm × 3.5 mm. An optical fiber drop cable as the fiber cable 1 was obtained.
[0033]
As a result of the evaluation, all the optical fibers 3 were 1.55 μm and the loss characteristics were 0.25 dB / km or less. In the lateral pressure characteristics as mechanical characteristics, even when the cable was sandwiched between flat plates having a pressing width of 100 mm and a load of 1960 N was applied from above, no increase in loss was observed, and good characteristics were exhibited. Regarding bending, there was no increase in loss even when bending at 60 mmφ.
[0034]
As for the leadability / connectivity of the optical fiber, eight optical fiber cores 3 can be easily formed by tearing the sheath 9 from the notch 13 so that the intervening body 5 is stuck to the sheath together, roughly wound, and integrated together. I was able to come apart. This optical fiber 3 could be easily connected to another branch cable.
[0035]
The movement of the optical fiber core 3 was performed by laying the cable 20 m (open at both ends) vertically on the tray and continuously applying a vibration of 1 Hz in frequency and 10 mm in amplitude to the optical fiber cable 1 for one week. The movement was below the detection limit (0.1 mm or less).
[0036]
As a comparative example, five prototypes of a cable in which an intervening body was vertically attached (not wrapped) around a wire were manufactured under manufacturing conditions considered to be almost the same. As a result, in two of the cables, the loss of one fiber was increased by 0.4 dB / km. When the cable was disassembled, a slight meandering of the loss increasing fiber was observed.
[0037]
(Example 2)
The pitch and tension of the intervening body 5 in which the eight optical fiber core wires 3 were roughly wound when the optical fiber drop cable of the first embodiment was trial manufactured were examined. As a result, n = 5 cables each having various pitches and tensions were prepared, and the initial loss was evaluated. When the pitch exceeded 1000 mm and the tension was less than 490 mN, 1 out of 5 Fibers with increasing losses appeared in the cable. When the tension exceeded 4900 mN, the loss increased due to the lateral pressure. When the pitch is less than 10 mm, the effect of coarsely winding the plurality of core wires 3 is small.
[0038]
Further, as another example, the optical fiber core wire 3 includes four wires, the two core tapes include four wires, and the intervening member 5 includes nylon yarn, polypropylene yarn, or glass fiber that is a plastic fiber. Prototypes containing the yarn and the optical fiber cable 1 having the structure shown in FIG. 1 were produced and evaluated in the same manner as above, but all were good.
[0039]
The present invention is not limited to the above-described embodiment, but can be embodied in other modes by making appropriate changes. In the embodiment of the present invention described above, the example in which the intermediate body 5 is coarsely wound when the plurality of optical fiber cores 3 are supplied to the extruder 23 has been described. May be supplied to the extruder 23.
[0040]
【The invention's effect】
As understood from the above description of the embodiment of the invention, according to the invention of claim 1, when the cable sheath is torn out from the notch portion and the optical fiber core is led out, the cable sheath is interposed. Since it is not blocked by the optical fiber and does not penetrate into the inside of the optical fiber core, it can be easily opened. In addition, since it is manufactured to have a small diameter and an intervening body such as a fiber serves as a cushion for the optical fiber, the loss characteristics can be stabilized. Further, since all of the optical fiber core wires are collectively wound by the intermediate body, all of the optical fiber core wires can be firmly integrated. Moreover, since all of the optical fiber cores are integrated, the bending rigidity is increased, and the meandering of the optical fiber core due to contraction of the cable at a low temperature can be suppressed. Further, the optical fiber cable becomes simple, there is no assembly process, and the processing cost can be reduced.
[0041]
According to the second aspect of the present invention, the optical element portion is used as an optical fiber drop cable by integrating long cable support wire portions in which a support wire is covered with a sheath in parallel with each other. This has the same effect as the first aspect.
[0042]
According to the third aspect of the invention, if the tension of the coarse winding is too large, side pressure and bending are applied to the optical fiber, and there is a concern that the loss will increase. If the tension is too small, the optical fiber will not be integrated because it will not be integrated. A tension of 490 mN or more and 4900 mN or less is desirable. If the winding pitch is too small, the productivity is poor, and if the winding pitch is too large, the optical fiber is not integrated, so that a pitch of 10 mm or more and 1000 mm or less is desirable.
[0043]
According to the fourth aspect of the present invention, similarly to the first aspect, when the cable sheath is torn out from the notch portion to output the optical fiber core, the cable sheath is blocked by the intervening body and extends to the inside of the optical fiber core. Because it does not penetrate, it can be easily put out. In addition, the loss characteristics can be stabilized because the intermediate member is manufactured to have a small diameter and the intermediate member serves as a cushion for the optical fiber core wire. Further, since all of the optical fiber core wires are collectively wound by the intermediate body, all of the optical fiber core wires can be firmly integrated. Moreover, since all of the optical fiber cores are integrated, the bending rigidity is increased, and the meandering of the optical fiber core due to contraction of the cable at a low temperature can be suppressed. Further, the optical fiber cable becomes simple, there is no assembly process, and the processing cost can be reduced.
[0044]
According to the fifth aspect of the present invention, the optical element portion is used as an optical fiber drop cable because the long cable support wire portions in which the support wires are covered with the sheath are integrated in parallel with each other. Thus, the same effects as those of the first aspect can be obtained.
[0045]
According to the invention of claim 6, when the intervening body is supplied to the extruder, the optical fiber cable is continuously and rationally manufactured because it is roughly wound around all of the optical fiber core wires. it can.
[0046]
According to the invention of claim 7, if the tension of the coarse winding is too large, lateral pressure and bending are applied to the optical fiber, and there is a concern that the loss will increase. If the tension is too small, the optical fiber will not be integrated and will be scattered. A tension of 490 mN or more and 4900 mN or less is desirable. If the winding pitch is too small, the productivity is poor, and if the winding pitch is too large, the optical fiber is not integrated, so that a pitch of 10 mm or more and 1000 mm or less is desirable.
[Brief description of the drawings]
FIG. 1 is a sectional view of an optical fiber cable according to an embodiment of the present invention.
FIG. 2 is a sectional view of another optical fiber cable according to the embodiment of the present invention.
FIG. 3 is an explanatory diagram for manufacturing another optical fiber cable according to the embodiment of the present invention.
FIG. 4 is a sectional view of an extrusion head.
FIG. 5 is a perspective view of a nip portion.
FIG. 6 is a perspective view of a die part.
FIG. 7 is a sectional view of a conventional optical fiber cable.
FIG. 8 is a sectional view of another conventional optical fiber cable.
FIG. 9 is a sectional view of another conventional optical fiber cable.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Optical fiber cable 3 Optical fiber optical fiber core wire 5 Intermediate 7 Strength member for optical element 9 Cable sheath 11 Optical element section 13 Notch section 15 Support wire 17 Sheath 19 Cable support wire section 21 Neck 23 Extruder

Claims (7)

An optical fiber core wire composed of one or more strands or a tape core wire, an interposer in which all of the optical fiber core wires are collectively wound together, and are disposed in parallel in the vicinity of the interposer on both sides. A surface of the cable sheath on both sides of the interposer in a direction orthogonal to a direction in which the strength members for optical elements are covered with a cable sheath, and in a direction perpendicular to the direction in which the strength members for optical elements are connected. An optical fiber cable characterized in that a notch is formed on the optical fiber cable. 2. The optical fiber cable according to claim 1, wherein a long cable support wire portion having a support wire covered with a sheath is integrated in parallel with the optical element portion. The coarse winding tension when the intermediate body is roughly wound around all of the optical fiber core wires at a time is 490 mN or more and 4900 mN or less, and the pitch is 10 mm or more and 1000 mm or less. Fiber optic cable. An optical fiber core wire composed of one or more strands or a tape core wire, an interposer in which all of the optical fiber core wires are collectively wound together, and are disposed in parallel in the vicinity of the interposer on both sides. An optical fiber core consisting of one or a plurality of strands or tape optical cores and an optical fiber core consisting of one or a plurality of optical fibers are extruded by extruding a thermoplastic resin into the extruder while running the optical element tensile strength members. It consists of a long optical element part covered with a cable sheath with an interposer in which all of the cords are roughly wound in a lump and a tensile strength element for an optical element arranged in parallel on both sides in the vicinity of the interposer. Manufacturing an optical fiber cable in which notches are formed on the surface of a cable sheath on both sides of the intervening member in a direction orthogonal to a direction in which the tensile members for optical elements are connected. Method of manufacturing an optical fiber cable characterized. An optical fiber core wire composed of one or more strands or a tape core wire, an interposer in which all of the optical fiber core wires are collectively wound together, and are disposed in parallel in the vicinity of the interposer on both sides. An optical element strength member, an optical fiber core comprising a single or plural strands or a tape optical fiber core, by running a support wire and supplying the extruder with a thermoplastic resin while feeding the extruder. A long optical element in which a cable sheath covers an intervening body in which all of the optical fiber core wires are collectively roughly wound and a tensile element for an optical element which is arranged in parallel in the vicinity of the intervening side and on both sides. A notch on the surface of the cable sheath on both sides of the intervening body in a direction perpendicular to the direction in which the tensile elements for the optical elements are connected. A method of manufacturing an optical fiber cable, characterized in that the cable support wire portion of the elongated coated support wire with a sheath to produce a fiber optic cable in parallel to integrated with each other. The method for manufacturing an optical fiber cable according to claim 4, wherein, when the intervening body is supplied to the extruder, the intermediate body is roughly wound around all of the optical fiber core wires. 7. The method according to claim 4, wherein the coarse winding tension is 490 mN or more and 4900 mN or less and the pitch is 10 mm or more and 1000 mm or less when the intermediate body is roughly wound around all of the optical fiber cores. A method for manufacturing the optical fiber cable according to the above.

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