JP2020091397A - Optical fiber cable, and method and apparatus for manufacturing optical fiber cable - Google Patents

Abstract

To provide an optical fiber cable that accomplishes a reduction in diameter of a cable outer periphery.SOLUTION: An optical fiber cable 1 comprises a spacer 10 having grooves 18 extending along a direction of an axis G, and optical units 20 each that have at least one coated optical fiber and are housed in the grooves 18. An openable and closable lid 14 is provided so as to close an opening of each of the grooves 18 on an outer periphery of the spacer 10.SELECTED DRAWING: Figure 1

Description

The present invention relates to an optical fiber cable, an optical fiber cable manufacturing method, and an optical fiber cable manufacturing apparatus.

Patent Document 1 discloses an optical fiber cable in which a plurality of wide grooves are provided on the outer circumference of a slot rod. In this optical fiber cable, an optical fiber unit including a plurality of optical fiber core wires is housed in each of these grooves.

JP, 2013-133611, A JP, 2003-195131, A JP, 2018-017774, A

In the optical fiber cable described in Patent Document 1, since the width of the groove for accommodating the optical unit including the optical fiber core wire is relatively wide, the jacket or the presser winding arranged on the outer periphery of the slot rod falls into the groove, It narrows the space to store the optical unit. If the space to be stored becomes narrow, a slight bend (microbend) is likely to occur in the optical fiber core wire, and the optical transmission loss increases. Therefore, in the multi-fiber high-density cable, such a drop is taken into consideration in advance, and a design is made so that the storage density of the optical fiber cores falls within an appropriate range. Therefore, the outer diameter of the optical fiber cable tends to be large.

An object of the present invention is, as one aspect, to provide an optical fiber cable capable of reducing the outer diameter of the cable. Another object of the present invention is to provide a manufacturing method or manufacturing apparatus for manufacturing such an optical fiber cable.

An optical fiber cable according to one aspect of the present invention includes a spacer having a groove extending along the axial direction, and an optical unit having at least one optical fiber core wire and housed in the groove. On the outer periphery of the spacer, a lid that can be opened and closed so as to close the opening of the groove is provided.

A method for manufacturing an optical fiber cable according to an aspect of the present invention includes a groove having a groove extending along an axial direction, and a spacer having a lid that can be opened and closed with respect to an opening of the groove on an outer periphery and is wound from a drum. In the process of rewinding to a drum, the step of opening the lid of the spacer with an opening device, and the step of, after the step of opening the lid, housing the optical unit having at least one optical fiber core wire in the groove of the spacer, Closing the lid.

An optical fiber cable manufacturing apparatus according to an aspect of the present invention includes a spacer having a groove extending along an axial direction and having a lid that can be opened and closed with respect to an opening of the groove on an outer periphery from a first position. A feed drum and a take-up drum for feeding to the position 2, an opening device for opening the lid of the spacer, and a bobbin for feeding to the spacer an optical unit having at least one optical fiber core. A supply device for accommodating the optical unit supplied from the bobbin is provided in the groove of the spacer with the lid opened.

According to one aspect of the present invention, it is possible to provide an optical fiber cable in which the outer circumference of the cable is reduced in diameter.

FIG. 1 is a diagram showing a cross-sectional configuration of the optical fiber cable according to the present embodiment. FIG. 2 is a diagram showing a spacer included in the optical fiber cable shown in FIG. FIG. 3 is a diagram showing a manufacturing method and a manufacturing apparatus of the optical fiber cable shown in FIG. FIG. 4A shows an opening eye plate in the manufacturing apparatus shown in FIG. 3, and FIG. 4B shows a collective eye plate in the manufacturing apparatus shown in FIG. FIG. 5: is a figure which shows the cross section of the optical fiber cable which concerns on a modification.

[Description of Embodiments of the Present Invention]
First, the contents of the embodiments of the present invention will be listed and described. An optical fiber cable according to an embodiment of the present invention includes a spacer having a groove extending along the axial direction, and an optical unit having at least one optical fiber core wire and housed in the groove. A lid that can be opened and closed is provided on the outer periphery of the spacer so as to close the opening of the groove.

In this optical fiber cable, a lid is provided so as to close the opening of the groove. With this configuration, it is possible to prevent an outer cover or the like arranged outside the spacer from falling into the groove and narrowing the storage space of the optical unit. Therefore, according to this optical fiber cable, it is possible to reduce the diameter of the outer circumference of the cable while suppressing an increase in optical transmission loss caused by the microbend generated in the optical fiber core wire. Further, in this optical fiber cable, since the lid can be opened and closed, it is possible to store the optical unit in the groove during manufacturing without any problem.

In the above optical fiber cable, the groove of the spacer may extend spirally along the axial direction. According to this configuration, when the optical fiber cable is wound on the drum, the lengths of the tracks of all the grooves are equal, and the optical fiber housed in the grooves is not excessively compressed or stretched. As a result, it is possible to further suppress an increase in optical transmission loss due to minute bending of the optical fiber. The spirally formed groove may be, for example, S-shaped, Z-shaped, or SZ-shaped.

In the above-mentioned optical fiber cable, the cross-sectional shape of the lid may be convex in the direction from the inside to the outside of the spacer. With this configuration, it is possible to secure a wider space for housing the optical unit. Therefore, according to the optical fiber cable of this aspect, it is possible to further suppress an increase in optical transmission loss caused by the microbend generated in the optical fiber core wire.

In the above optical fiber cable, the lid may be connected to one end of one of the pair of side walls that define the groove therebetween, and may be formed continuously in the longitudinal direction. With this configuration, the opening/closing operation of the lid can be easily performed. Further, since a part of the lid is already fixed, it is possible to more reliably fix the entire lid when the lid is closed. Further, according to this structure, since the spacer having the lid and one of the side walls continuous can be integrally formed by extrusion molding or the like, it is possible to stabilize the axial dimension of the cable and reduce the manufacturing cost. it can. In addition, in this structure, the lid may be operable around the connecting portion with one side wall as an axis.

In the above optical fiber cable, the groove may be formed so that the width thereof increases from the inside of the spacer toward the outer circumference. According to this configuration, it is possible to secure a wider space for housing the optical unit in the spacer. When the outer peripheral cross section of the spacer is circular, for example, it is possible to more efficiently secure a space for housing the optical unit in the spacer. Such a groove may have, for example, a V shape.

In the above fiber optic cable, the thickness of the lid may be less than the thickness of the pair of sidewalls defining the groove therebetween. With this configuration, it is possible to secure a wider space for housing the optical unit, suppress an increase in optical transmission loss, and reduce the diameter of the outer circumference of the cable.

In the above optical fiber cable, the outer diameter of the optical fiber may be 125 μm or more and 190 μm or less. With this configuration, a larger number of optical fiber core wires can be stored in the optical fiber cable.

In the above optical fiber cable, the outer diameter of the clad of the optical fiber may be 80 μm or more and 120 μm or less. According to this configuration, it is possible to store more optical fiber core wires in the optical fiber cable.

In the above optical fiber cable, the increase in optical transmission loss at a wavelength of 1550 nm when the optical fiber core wire is wound with a tension of 8 N on a bobbin in which #240 sandpaper is wound around a body surface of 280 mm in diameter is 5 dB/ It may be less than or equal to km. In this case, an optical fiber cable that suppresses an increase in optical transmission loss can be obtained.

The fiber optic cable described above may further comprise a water absorbing yarn, which may be housed in a groove. With this configuration, it is possible to prevent water from running when water enters the groove of the spacer. In particular, the above optical fiber cable has a structure in which the groove is covered with a lid, and it is difficult to use a water absorbing tape or the like from the outside. Therefore, by providing a water-absorbing yarn in the groove, a structure having a lid can be adopted, and water running into the groove can be prevented.

A method for manufacturing an optical fiber cable according to an embodiment of the present invention includes a spacer having a groove extending along an axial direction and having a lid which can be opened and closed with respect to an opening of the groove on an outer periphery and is wound from a drum. In the process of rewinding to the take-up drum, the step of opening the lid of the spacer with the opening device, the step of storing the optical unit having at least one optical fiber core wire in the groove of the spacer after the step of opening the lid, and the spacer Closing the lid of. According to this manufacturing method, it is possible to easily manufacture an optical fiber cable including a spacer having a lid that closes the groove. That is, as an example, it is possible to easily manufacture the above optical fiber cable in which the outer circumference of the cable is reduced in diameter.

The method of manufacturing the optical fiber cable may further include a step of winding a thread or tape around the outer circumference of the spacer so as to press the lid from the outer circumference after the step of closing the lid. According to this manufacturing method, the lid of the optical fiber cable can be closed more reliably.

An optical fiber cable manufacturing apparatus according to an embodiment of the present invention includes a spacer having a groove extending along an axial direction and having a lid that can be opened and closed with respect to an opening of the groove on an outer periphery from a first position. A delivery drum and a take-up drum for feeding to a second position, an opening device for opening the lid of the spacer, and a bobbin for feeding to the spacer an optical unit having at least one optical fiber core. A supply device for accommodating the optical unit supplied from the bobbin is provided in the groove of the spacer with the lid opened. According to this manufacturing apparatus, it is possible to easily manufacture an optical fiber cable including a spacer having a lid that closes the groove. That is, as an example, it is possible to easily manufacture the above optical fiber cable in which the outer circumference of the cable is reduced in diameter.

[Details of the embodiment of the present invention]
Specific examples of the optical fiber cable, the manufacturing method thereof, and the manufacturing apparatus thereof according to the embodiment of the present invention will be described below with reference to the drawings. It should be noted that the present invention is not limited to these exemplifications, and is shown by the scope of the claims, and is intended to include meanings equivalent to the scope of the claims and all modifications within the scope. In the following description, the same reference numerals are given to the same elements in the description of the drawings, and overlapping description will be omitted.

FIG. 1 is a diagram showing a cross-sectional configuration of an optical fiber cable according to an embodiment. As shown in FIG. 1, the optical fiber cable 1 is a cable extending in the direction of the axis G (direction orthogonal to FIG. 1), and includes a spacer 10 and a large number of optical units 20 housed in a groove 18 of the spacer 10. The coarse thread 30 covering the outer periphery of the spacer 10 (lid 14) and the cable jacket 40 are provided. The optical unit 20, which will be described in detail later, includes a plurality of optical fiber cores, and the plurality of optical fiber cores are unitized by PET tape or the like. The optical fiber cable 1 has, for example, an outer diameter of 8 mm to 30 mm, but is not limited to this.

FIG. 2 is a diagram showing the spacer 10 included in the optical fiber cable 1. As shown in FIG. 2, the spacer 10 is configured to extend spirally in the direction of the axis G (direction orthogonal to FIG. 2) with this cross-sectional shape as a whole, and includes a central portion 11 and eight side walls 12. , Eight lids 14 and a strength member 16. The strength member 16 is made of, for example, a steel strand extending in the axial direction or a fiber reinforced plastic, and is embedded inside the central portion 11. The strength member 16 improves the tensile strength of the optical fiber cable 1. The portion of the spacer 10 excluding the strength member 16 is made of, for example, a plastic resin such as polyethylene.

The side wall 12 is a wall body that extends radially from the outer peripheral surface of the central portion 11 toward the outer periphery of the spacer 10. Each side wall 12 is provided, for example, so that the angles formed by the adjacent side walls 12 are equal. Each side wall 12 forms a pair of side walls with an adjacent side wall, and defines a groove 18 for accommodating the optical unit 20 between the pair of side walls. The groove 18 has, for example, a V shape, and is formed in a tapered shape so that the width thereof increases from the inside of the spacer 10 to the outer circumference thereof. The groove 18 does not have to be V-shaped, but when the outer peripheral shape of the spacer 10 is a circle (or an ellipse), the groove 18 has a shape that spreads from the inside to the outside so that a space for housing the optical unit 20 is provided. It can be secured more widely. Note that the groove 18 may be a straight groove or a groove that spreads inward. The groove 18 is provided so as to extend in a spiral shape along the axial direction of the spacer 10. The spiral direction may be S-shaped, Z-shaped, or SZ-shaped. In the example shown in FIG. 1, three optical units 20 are stored in one groove 18, and 24 optical units 20 are stored in a total of eight grooves 18.

The lid 14 is a structure for closing the opening of the groove 18 defined by the side wall 12, and has a convex shape in the direction from the inside to the outside of the spacer 10. The lid 14 may have an arc shape along the outer peripheral surface of the spacer 10 or may have an arc shape protruding outward from the arc shape. The lid 14 is formed so that its base end 14a is connected to the tip 12a of the side wall 12 and is continuous in the axial direction (longitudinal direction). Since the spacer 10 is made of an elastically deformable resin or the like, the lid 14 can move up and down about the connecting portion (the tip 12a) with the side wall 12 as an axis, whereby the lid 14 opens in the groove 18. It can be opened and closed with respect to the section. The opening of the groove 18 can have, for example, a width of 3 mm to 10 mm at the outer circumference, but is not limited thereto.

As shown in FIG. 2, the lid 14 is separated from the edge of the tip 12a of the side wall 12 facing the continuous side wall 12 to some extent before being incorporated into the optical fiber cable 1. On the other hand, as shown in FIG. 1, after the lid 14 is assembled into the optical fiber cable 1, the lid 14 is pressed inward by the coarse winding thread 30 so that the tip 14 b of the lid 14 is at the edge of the tip 12 a of the adjacent side wall 12. It will get caught on top. As a result, the lid 14 does not fall into the groove 18. The lid 14 is formed to have a small thickness, for example, thinner than the side wall 12. The thickness of the lid 14 may be, for example, 0.1 mm to 0.5 mm, but is not limited to this.

Here, returning to FIG. The optical unit 20 housed in the groove 18 of the spacer 10 is a unit including a large number of optical fiber core wires. For example, the optical unit 20 can be configured as one optical unit by assembling 12 intermittent tapes including 12 optical fiber core wires. For example, the optical unit 20 may be wound around the outer periphery thereof with PET tape or the like to form one optical unit. In the example shown in FIG. 1, the optical fiber cable 1 accommodates a total of 24 optical units 20 of 3×8, which constitutes an optical fiber cable including a large number of optical fiber cores such as 3456 cores. To do.

The coarse winding yarn 30 constitutes a layer for pressing and fixing the lid 14 from the outer periphery. The coarse winding thread 30 closes the opening of the groove 18 so that the lid 14 separated from the edge of the tip 12a of the side wall 12 is caught by the side wall 12. The coarse winding yarn 30 is, for example, a nylon yarn. Instead of the coarse winding yarn 30, the lid 14 may be pressed and fixed from the outer periphery by a tape.

The cable jacket 40 is a resin layer that further covers the spacer 10 whose outer periphery is pressed by the coarse winding yarn 30 from the outer periphery, and functions as a protective layer of the optical fiber cable 1. The cable jacket 40 is made of polyethylene, for example, and imparts weather resistance, heat resistance, water resistance, etc. to the optical fiber cable 1.

Next, a manufacturing method and a manufacturing apparatus for manufacturing the optical fiber cable 1 will be described with reference to FIGS. 3, 4A and 4B. FIG. 3 is a diagram showing a manufacturing method and a manufacturing apparatus of the optical fiber cable 1. FIG. 4A shows an opening eye plate in the manufacturing apparatus shown in FIG. 3, and FIG. 4B shows a collective eye plate in the manufacturing apparatus shown in FIG. The opening eye plate is an example of an opening device for opening the lid of the spacer, and the collecting eye plate is an example of a supply device for accommodating the optical unit in the groove of the spacer with the lid open.

As shown in FIG. 3 and FIG. 4, the manufacturing apparatus 100 for manufacturing the optical fiber cable 1 includes a delivery drum 101, a supply bobbin 102, a coarse yarn feeder 103, a winding drum 104, and a first conveyor. The roller 105, the second conveying roller 106, the opening eye plate 110, and the collecting eye plate 120 are provided. The delivery drum 101 is a bobbin around which a spacer 10 extending in the axial direction is wound. The spacer 10 delivered from the delivery drum 101 is transported by the first transport roller 105 and the second transport roller 106, and then wound by the winding drum 104. That is, the spacer 10 is sent from the sending drum 101 to the winding drum 104.

The supply bobbin 102 is a bobbin for supplying the optical unit 20 including a plurality of optical fiber core wires to the spacer 10 being transported. The supply bobbins 102 are provided according to the number of the optical units 20 accommodated in the optical fiber cable 1. When manufacturing the optical fiber cable 1 shown in FIG. 1, for example, 24 supply bobbins 102 are provided.

The coarse winding yarn feeder 103 is a device that supplies a yarn for closing the lid 14 and pressing it from the outer periphery after the optical unit 20 is housed in the groove 18 of the spacer 10 to the spacer 10 being conveyed. .. The coarse winding yarn feeder 103 winds the yarn (for example, nylon yarn) to be supplied around the outer periphery of the spacer 10 in a spiral shape.

The aperture plate 110 is a ring-shaped member, and as shown in FIG. 4A, has a protrusion 114 that protrudes inward from the outer peripheral portion 112. The protruding portion 114 is a member for guiding the lid 14 of the spacer 10 in the opening direction by using the force being conveyed. The tip of the protrusion 114 enters the groove 18 when the lid 14 is opened. The optical fiber cable 1 shown in FIG. 1 is provided with eight lids 14, and in the example shown in FIG. 4A, the opening eye plate 110 corresponds to the lid 14 and has eight protruding portions 114. Is equipped with. A space is formed inside the eight protrusions 114 (on the tip side of the protrusions), and the central portion 11 of the spacer 10 and the like are arranged in the space.

The aggregate plate 120 is a ring-shaped member, and includes a protruding portion 124 that protrudes inward from the outer peripheral portion 122, as shown in FIG. 4B. The projecting portion 124 is a member for guiding the optical unit 20 supplied from the supply bobbin 102 to the groove 18 while keeping the lid 14 open. In the joint plate 120, in order to achieve such a function, the protruding portion 124 is formed shorter than the protruding portion 114 so that it does not enter the groove 18. On the other hand, the protruding portion 124 has a holding portion 126 at the inner tip thereof so that the optical unit 20 accommodated in the groove 18 does not jump out.

In order to manufacture the optical fiber cable 1 by using the optical fiber cable manufacturing apparatus 100 having such a configuration, first, the spacer 10 provided with the lid 14 and the groove 18 is wound from the delivery drum 101 to the spacer. 10 is sent out, and the spacer 10 is wound up by the winding drum 104. At this time, the feed drum 101 and the take-up drum 104 are rotated around a shaft on which the spacer runs in a direction of canceling the spiral of the groove, so that the opening eye plate 110 and the aggregate eye plate 120 are installed. In, a specific groove always faces a specific direction. Then, while the spacer 10 is being sent out and being sent from the drum 101 to the winding drum 104, the spacer 10 is passed through the opening eye plate 110, and the lid 14 of the spacer 10 is moved to the opening position by the protrusion 114 ((a in FIG. 4A. See)).

Subsequently, the spacer 10 having the lid 14 opened is conveyed to a position where the aggregate plate 120 is installed and passes through the aggregate plate 120. At this time, each optical unit 20 supplied from the plurality of supply bobbins 102 is housed in the groove 18 of the spacer 10 by the aggregate plate 120. The spacer 10 in which the optical unit 20 is accommodated by the aggregate plate 120 then travels toward the winding drum 104, and the lid 14 is disengaged from the projecting portion 124 of the aggregate plate 120 and moves in the closing direction. The lid 14 of the spacer 10 at this time is in the semi-closed state shown in FIG. That is, the tip 14b of the lid 14 is separated from the edge of the tip 12a of the side wall 12.

Subsequently, while the spacer 10 in which the optical unit 20 is housed in the groove 18 is being sent to the second transport roller 106, the coarse winding yarn supplied from the coarse winding yarn supplying device 103 is pressed so as to press the lid 14 from the outer periphery. Wrap around the outer periphery of the spacer 10. As a result, the lid 14 of the spacer 10 moves so that the tip 14 b is caught by the edge of the tip 12 a of the side wall 12, and the opening of the groove 18 is closed by the lid 14. The spacer 10 on which the coarsely wound yarn is wound is then twisted again in the first rotation direction in the vicinity of the second transport roller 106 to become the semi-finished product cable 1 a, and then wound on the winding drum 104. The semi-finished product cable 1a wound on the winding drum 104 is then covered with the cable jacket 40 by another coating device. As a result, the optical fiber cable 1 shown in FIG. 1 is completed.

As described above, in the optical fiber cable 1 according to the present embodiment, the lid 14 is provided so as to close the opening of the groove 18. With this configuration, it is possible to prevent the cable jacket 40 and the like arranged outside the spacer 10 from falling into the groove 18 and narrowing the storage space of the optical unit 20. Therefore, according to the optical fiber cable 1, it is possible to reduce the diameter of the outer circumference of the cable while suppressing an increase in optical transmission loss due to the occurrence of microbends in the optical fiber core wire. Further, in the optical fiber cable 1, since the lid 14 can be opened and closed, it is possible to store the optical unit 20 in the groove 18 during manufacturing without any problem.

In the optical fiber cable 1, the groove 18 of the spacer 10 extends spirally along the axial direction. With this configuration, when the optical fiber cable 1 is wound on the drum, the lengths of the trajectories of all the grooves 18 become equal, and the optical fiber core wire (optical unit 20) housed in the grooves 18 is excessively compressed. Or tensile strain does not occur. As a result, it is possible to suppress an increase in optical transmission loss due to a slight bending of the optical fiber core wire.

In the optical fiber cable 1, the cross-sectional shape of the lid 14 is convex in the direction from the inside of the spacer 10 to the outside. According to this configuration, it is possible to secure a wider space for housing the optical unit 20. Therefore, according to the optical fiber cable 1, it is possible to suppress an increase in optical transmission loss due to the microbend occurring in the optical fiber core wire.

In the optical fiber cable 1, the lid 14 is connected to one end 12a of the pair of side walls 12 defining the groove 18 therebetween and is continuously formed in the axial direction. According to this configuration, the opening/closing operation of the lid 14 can be easily performed, and the lid 14 can be fixed more securely when the lid 14 is closed. Further, since the spacer 10 in which the lid 14 and the side wall 12 are continuous can be manufactured by extrusion molding or the like, it is possible to stabilize the axial dimension of the cable and reduce the manufacturing cost.

In the optical fiber cable 1, the groove 18 is formed so that the width thereof widens from the inside of the spacer 10 to the outer periphery thereof. With this configuration, it is possible to secure a wider space in the spacer 10 for housing the optical unit 20. When the outer peripheral cross section of the spacer 10 is circular as in the present embodiment, it is possible to more efficiently secure a space for accommodating the optical unit 20 in the spacer 10.

In the fiber optic cable 1, the thickness of the lid 14 may be less than the thickness of the pair of sidewalls 12 defining the groove 18 therebetween. According to this configuration, it is possible to secure a wider space for housing the optical unit 20 to suppress an increase in optical transmission loss and to reduce the diameter of the outer circumference of the cable.

Further, according to the manufacturing method and the manufacturing apparatus of the optical fiber cable according to the present embodiment, the optical fiber cable including the spacer 10 having the lid 14 that closes the groove 18 can be easily manufactured. That is, it is possible to easily manufacture the optical fiber cable 1 in which the outer circumference of the cable is reduced in diameter. Further, in this method for manufacturing an optical fiber cable, after closing the lid 14, a thread or tape is wound around the outer periphery of the spacer 10 so as to press the lid 14 from the outer periphery. Thereby, the lid 14 of the optical fiber cable 1 can be closed more reliably.

Although the embodiments of the present invention have been described above in detail, the present invention is not limited to the above embodiments and can be applied to various embodiments. For example, in the above-described embodiment, a general optical fiber core wire is used as the optical fiber core wire forming the optical unit 20, but an optical fiber having an extremely small diameter such that the outer diameter of the optical fiber core wire is 125 μm or more and 190 μm or less. The optical unit including the core wire may be housed in the groove 18 of the spacer 10. Further, an optical unit including an optical fiber core wire having an extremely small diameter such that the outer diameter of the cladding of the optical fiber core wire is 80 μm or more and 120 μm or less may be housed in the groove 18 of the spacer 10. According to these configurations, it is possible to accommodate a larger number of optical fiber core wires in the optical fiber cable.

In the case of adopting an optical fiber with an extremely small diameter, the optical fiber core wire is wound around a bobbin of #240 sandpaper on the surface of a body having a diameter of 280 mm on a bobbin with a tension of 8 N to reduce the optical transmission loss at a wavelength of 1550 nm. It is preferable to use an optical fiber core wire whose increase is 5 dB/km or less. Since the outer diameter of the optical fiber having an extremely small diameter is thin, the optical transmission loss due to lateral pressure is likely to increase. However, it is possible to suppress an increase in optical transmission loss due to lateral pressure or the like by using an extremely thin optical fiber core wire that satisfies the above-mentioned performance.

The optical fiber cable according to the present embodiment may further include a water absorbing yarn 19, as shown in FIG. 5, and the yarn 19 may be housed in the groove 18. With this configuration, it is possible to prevent water running when water enters the groove 18 of the spacer 10. In particular, the optical fiber cable 1A has a configuration in which the groove 18 is closed by the lid 14, and it is difficult to use a water absorbing tape or the like from the outside. Therefore, by providing the water-absorbing yarn 19 in the groove 18, it is possible to prevent the running of water that has entered the groove 18 while adopting the configuration having the lid 14. Such a water absorbing yarn 19 may be provided at the bottom of the groove 18 or in the middle of the plurality of optical units 20, for example.

The optical fiber cables 1 and 1A according to the present embodiment have a configuration in which eight grooves 18 are provided on the outside, but the number of grooves for accommodating the optical unit is not limited to this. For example, the optical fiber cable may have a structure having four grooves on the outside or a structure having six grooves on the outside. In these cases, the volume of the space (groove) for accommodating the optical unit 20 can be further increased by reducing the number of side walls as compared with the optical fiber cable having eight grooves, so that the optical fiber core wire It is possible to reduce the diameter of the outer circumference of the cable while suppressing an increase in optical transmission loss caused by the microbend. In addition, more optical fiber cores can be stored in the optical fiber cable.

DESCRIPTION OF SYMBOLS 1... Optical fiber cable, 10... Spacer, 11... Central part, 12... Side wall, 12a... Tip, 14... Lid, 14a... Base end, 14b... Tip, 16... Tensile body, 18... Groove, 20... Optical unit, 30... Coarse winding yarn, 40... Cable jacket, 100... Manufacturing device, 101... Sending drum, 102... Supply bobbin, 103... Coarse winding yarn feeder, 104... Winding drum, 105... First conveying roller, 106 ...Second conveying roller, 110...opening plate, 112...peripheral part, 114...projection part, 120...collecting plate, 122...peripheral part, 124...projection part, 126...pressing part.

Claims (14)

A spacer having a groove extending along the axial direction,
An optical unit having at least one optical fiber core and housed in the groove;
Equipped with
A lid that can be opened and closed is provided on the outer periphery of the spacer so as to close the opening of the groove.
Fiber optic cable. The groove of the spacer extends spirally along the axial direction,
The optical fiber cable according to claim 1. The cross-sectional shape of the lid is a convex shape in the direction from the inside to the outside of the spacer,
The optical fiber cable according to claim 1 or 2. The lid is connected to one end of one of a pair of side walls that define the groove therebetween and is continuously formed in the longitudinal direction.
The optical fiber cable according to any one of claims 1 to 3. The lid is operable about a connecting portion with the one side wall as an axis.
The optical fiber cable according to claim 4. The groove is formed so as to widen from the inside of the spacer toward the outer periphery,
The optical fiber cable according to any one of claims 1 to 5. The thickness of the lid is less than the thickness of the pair of sidewalls defining the groove,
The optical fiber cable according to any one of claims 1 to 6. The outer diameter of the optical fiber is 125 μm or more and 190 μm or less,
The optical fiber cable according to any one of claims 1 to 7. The outer diameter of the cladding of the optical fiber core is 80 μm or more and 120 μm or less,
The optical fiber cable according to any one of claims 1 to 8. An increase in optical transmission loss is 5 dB/km or less when the optical fiber core wire is wound around a bobbin having a #280 sandpaper on a body surface having a body diameter of 280 mm with a tension of 8 N.
The optical fiber cable according to any one of claims 1 to 9. Further comprising a yarn for absorbing water, the yarn being housed in the groove,
The optical fiber cable according to any one of claims 1 to 10. In the process of sending out a spacer having a groove extending along the axial direction and having a lid on the outer periphery that can be opened and closed with respect to the opening of the groove and rewinding it from the drum to the winding drum, the lid of the spacer is opened. Steps to open by
Storing an optical unit having at least one optical fiber core in the groove of the spacer after the step of opening the lid;
Closing the lid of the spacer;
And a method for manufacturing an optical fiber cable. After the step of closing the lid, further comprising a step of winding a thread or tape around the outer periphery of the spacer so as to press the lid from the outer periphery,
The method for manufacturing the optical fiber cable according to claim 12. A feed drum and a take-up drum for feeding a spacer having a groove extending along the axial direction and having a lid that can be opened and closed with respect to the opening of the groove on the outer periphery from a first position to a second position. When,
An opening device for opening the lid of the spacer,
A bobbin for supplying an optical unit having at least one optical fiber core wire to the spacer;
A supply device for accommodating the optical unit supplied from the bobbin in the groove of the spacer in a state where the lid is open,
An optical fiber cable manufacturing apparatus, comprising:

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