JP2023020224A - Spacer and optical cable - Google Patents

Abstract

To provide a spacer and an optical cable that enable prevention of a decrease in optical characteristics of a coated optical fiber mounted in an optical cable.SOLUTION: A spacer 2 comprises a tension member 22 and a spacer body 20 covering the tension member 22. The spacer body 20 has a central part 21 surrounding the tension member 22, and a pair of ribs 23 protruding from the central part 21 to the outside and extending in an axial direction of the spacer 2 without being twisted. The pair of ribs 23 are disposed in point symmetry with respect to a center axis Ax of the tension member 22.SELECTED DRAWING: Figure 1

Description

The present disclosure relates to spacers and optical cables.

Patent Literature 1 discloses an optical cable in which a plurality of optical fiber core wires are mounted. The optical cable is provided with a spacer having eight ribs. Adjacent ribs define grooves, and a plurality of optical fibers are mounted in each of the plurality of grooves.

JP 2020-091397 A

By the way, it is known that when the mounting density of the optical fiber core wires mounted on the optical cable increases, the probability that the optical fiber core wires collide with each other increases, and the transmission loss of the optical fiber core wires increases. ing. On the other hand, there is a demand to reduce the size (thinner diameter) of the optical cable while mounting many optical fibers in the optical cable. Here, the mounting density of the optical fiber core wires is obtained by dividing the mounting area of the optical fiber core wires by the mountable area of the optical fiber core wires. Therefore, as the number of optical fiber core wires to be mounted increases, the mounting density of the optical fiber core wires increases. Furthermore, even if the size of the optical cable is reduced, the mounting density of the optical fiber core wire is similarly increased. In this way, in order to prevent deterioration of the optical characteristics of the optical cable, it is possible to reduce the mounting density of the optical fiber core wires while reducing the diameter of the optical cable without reducing the number of the optical fiber core wires mounted in the optical cable. There is room to consider the method of On the other hand, a structure for holding the optical cable is also required.

An object of the present disclosure is to provide a spacer that holds an optical cable and an optical cable that can prevent deterioration of the optical properties of the optical fiber core wire mounted on the optical cable. In particular, the present disclosure provides a spacer and an optical cable that can prevent the deterioration of the optical characteristics of the optical fiber core wires without reducing the number of the optical fiber core wires mounted in the optical cable and reducing the diameter of the optical cable. With the goal.

A spacer according to one aspect of the present disclosure includes a tension member and a spacer body covering the tension member. The spacer main body has a central portion surrounding the tension member, and a pair of ribs projecting outward from the central portion and extending in the axial direction of the spacer without being twisted. The pair of ribs are arranged point-symmetrically with respect to the central axis of the tension member.

An optical cable according to an aspect of the present disclosure includes the spacer, a plurality of optical fiber core wires, and a sheath that covers the spacer and the plurality of optical fiber core wires. The optical cable is formed in a circular shape in a cross section perpendicular to the axial direction of the optical cable.

Advantageous Effects of Invention According to the present disclosure, it is possible to provide a spacer and an optical cable that can prevent deterioration of optical properties of optical fibers mounted on an optical cable.

FIG. 2 is a cross-sectional view of a spacer according to an embodiment of the present disclosure; 1 is a cross-sectional view showing an optical cable according to an embodiment of the present disclosure; FIG. 4 is a flowchart for explaining a method of manufacturing an optical cable; It is the figure which showed the manufacturing equipment of an optical cable roughly. FIG. 5 is a cross-sectional view showing a spacer according to a modification of the embodiment of the present disclosure; FIG. 4 is a cross-sectional view showing an optical cable according to a modification of the embodiment of the present disclosure;

[Description of Embodiment]
An outline of the embodiment will be described.
(1) a tension member;
a spacer body covering the tension member;
A spacer comprising
The spacer body is
a central portion surrounding the tension member;
a pair of ribs projecting outward from the central portion and extending in the axial direction of the spacer without being twisted;
has
The pair of ribs are arranged point-symmetrically with respect to the central axis of the tension member,
Spacer.

According to the above configuration, when the spacer is arranged in the optical cable, the cross-sectional area of the spacer in the cross section of the cable perpendicular to the axial direction of the spacer becomes small, so the area in which the optical fiber can be mounted increases in the cross section of the optical cable. . Therefore, the diameter of the optical cable can be reduced without reducing the number of optical fibers mounted on the optical cable. As a result, an increase in transmission loss of each optical fiber is prevented. Therefore, it is possible to provide a spacer capable of preventing deterioration of optical characteristics of each optical fiber core wire mounted on an optical cable. Furthermore, the tension member is positioned at the center of the spacer, and the pair of ribs are arranged point-symmetrically with respect to the central axis of the tension member. By arranging the tension member in the center of the spacer and symmetrically arranging the pair of ribs in this way, the tendency of the optical cable to bend in a predetermined direction is preferably prevented, and the handling of the optical cable is improved. do.

(2) in a cross section perpendicular to the axial direction of the spacer, the pair of ribs are arranged on the same straight line;
A spacer according to item (1).

According to the above configuration, since the height dimension of the spacer is small, it is possible to wind more spacers onto the drum.

(3) the pair of ribs are formed in an S shape in a cross section perpendicular to the axial direction of the spacer;
A spacer according to item (1).

According to the above configuration, a plurality of optical fibers can be supported by a pair of S-shaped ribs. In particular, a plurality of optical fibers can be arranged in a groove formed by a pair of S-shaped ribs, and a plurality of optical fibers can be roughly arranged along the pair of S-shaped ribs. It becomes possible to bind with a winding thread.

(4) each length of the pair of ribs is 5 mm or more and 20 mm or less;
The thickness of each of the pair of ribs is 0.5 mm or more and 2 mm or less.
The spacer according to any one of items (1) to (3).

From the viewpoint of miniaturization of the optical cable, the length of each rib is set to 5 mm or more and 20 mm or less. Moreover, the thickness of each rib is set to 0.5 mm or more and 2 mm or less from the viewpoint of the mounting density of the optical fiber core wires and the strength of the spacer. In particular, when the thickness of the rib is 0.5 mm or more and 2 mm or less, it is possible to reduce the mounting density of the optical fibers mounted on the optical cable while maintaining the strength of the spacer.

(5) the spacer according to any one of items (1) to (4);
a plurality of optical fiber core wires;
a sheath that covers the spacer and the plurality of optical fiber core wires;
An optical cable comprising
The optical cable is formed in a circular shape in a cross section perpendicular to the axial direction of the optical cable,
optical cable.

According to the above configuration, the cross-sectional area of the spacer in the cross section perpendicular to the axial direction of the spacer is smaller than the cross-sectional area of the optical cable having a circular cross section. , the mounting area of the optical fiber is increased. Therefore, it is possible to reduce the apparent mounting density of the optical fiber core wires mounted on the optical cable while reducing the diameter of the optical cable without reducing the number of the optical fiber core wires mounted on the optical cable. As a result, an increase in transmission loss of each optical fiber is prevented. Therefore, it is possible to provide an optical cable capable of preventing deterioration of the optical characteristics of each optical fiber core wire.

(6) The outer diameter of the spacer is 40 mm or less, and the number of optical fiber core wires mounted in the optical cable is 1000 or more.
The optical cable according to item (5).

According to the above configuration, the spacer has an outer diameter of 40 mm or less, and more than 1000 optical fibers are mounted on the optical cable. On the other hand, the packing density of the optical fiber core wires is reduced by the spacer having a small cross-sectional area, so that an increase in the transmission loss of each optical fiber core wire is prevented.

(7) The mounting density of the optical fiber core wires mounted on the optical cable is 50% or more and 60% or less.
The optical cable according to item (5) or item (6).

If the mounting density of the optical fiber core wires is 50% or more and 60% or less, the standard value of transmission loss of the optical fiber core wires of 0.3 dB/km is satisfied while maintaining the high packing density of the optical fiber core wires. becomes possible.

[Details of embodiment]
An embodiment of the present disclosure (hereinafter referred to as the present embodiment) will be described below with reference to the drawings. For convenience of explanation, the dimensions of each member shown in each drawing may differ from the actual dimensions of each member. In this embodiment, the X-axis direction, the Y-axis direction, and the Z-axis direction set for the spacer 2 shown in FIG. 1 are appropriately referred to. Each of the X, Y, and Z directions is perpendicular to the other two directions. For example, the X-axis direction is perpendicular to the Y-axis direction and the Z-axis direction. The Z-axis direction corresponds to the axial direction (longitudinal direction) of the spacer 2 shown in FIG. 1 and the optical cable 1 shown in FIG.

First, referring to FIG. 1, the spacer 2 according to this embodiment will be described below. FIG. 1 is a cross-sectional view showing a spacer 2 according to this embodiment. A cross section of the spacer 2 shown in FIG. 1 is a cross section perpendicular to the axial direction (Z-axis direction) of the optical cable 1 . The spacer 2 has a tension member 22 and a spacer body 20 . The tension member 22 is made of a high-tensile material (for example, copper wire, FRP (Fiber Reinforced Plastics), etc.) having resistance to tension and compression. The tension member 22 is positioned at the center of the spacer 2 .

The spacer body 20 is configured to cover the tension member 22 . The spacer main body 20 is made of, for example, a synthetic resin of polycarbonate (PC) and polybutylene terephthalate (PBT) or a hard resin material such as high density polyethylene (HDPE). The spacer body 20 has a central portion 21 surrounding the tension member 22 and a pair of ribs 23 projecting outward from the central portion 21 .

The spacer body 20 covers the tension member 22 in a state in which the adhesion between the tension member 22 and the spacer body 20 is weak. Specifically, when the length of the spacer 2 in the axial direction is 25 mm, the adhesion force between the tension member 22 and the spacer main body 20 is less than 100N. In other words, the adhesion between the tension member 22 and the spacer body 20 is such that the spacer body 20 is separated from the tension member 22 when a pulling force of 100 N or more is applied to the spacer body 20 in the axial direction. getting weaker.

The pair of ribs 23 protrude outward from the central portion 21 and extend in parallel along the axial direction (Z-axis direction) of the spacer 2 without being helically twisted. A pair of ribs 23 are formed integrally with the central portion 21 . Also, the pair of ribs 23 are arranged point-symmetrically with respect to the central axis Ax of the tension member 22 (or the spacer 2 ) in a cross section perpendicular to the axial direction of the spacer 2 . In particular, the pair of ribs 23 are arranged on the same straight line in the X-axis direction.

Each length of the pair of ribs 23 in the X-axis direction is, for example, 5 mm or more and 20 mm or less. Each thickness of the pair of ribs 23 in the Y-axis direction is, for example, 0.5 mm or more and 2 mm or less. Moreover, as shown in FIG. 2, the outer diameter R of the spacer 2 may be 40 mm or less. The spacers 2 shown in FIG. 1 are supplied from a supply drum 101 shown in FIG. In this state, the pair of ribs 23 are not twisted along the axial direction. In the process of manufacturing the optical cable 1 (see FIG. 2), the pair of ribs 23 are twisted along the axial direction of the spacer 2 by the winding drum 104 (see FIG. 4). A method for manufacturing the optical cable 1 will be described later.

Next, the optical cable 1 according to this embodiment will be described below with reference to FIG. FIG. 2 is a cross-sectional view showing the optical cable 1 according to this embodiment. The cross section of the optical cable 1 shown in FIG. 2 is a cross section perpendicular to the axial direction (Z-axis direction) of the optical cable 1 . The cross-sectional shape of the optical cable 1 is circular. An optical cable 1 includes a spacer 2 , a plurality of optical units 3 , a non-woven fabric tape 4 and a sheath 5 .

A pair of ribs 23 defines two housing portions 24 in which the optical unit 3 is housed. Each housing portion 24 is, for example, helically twisted by twisting the spacer 2 along the axial direction. As the type of twist of each accommodating portion 24, S twist, Z twist, or SZ twist, which is a combination of S twist and Z twist, may be employed. The twist pitch of each accommodation portion 24 is, for example, between 600 mm and 2000 mm. Since each accommodating portion 24 is helically twisted along the axial direction of the spacer 2 , the optical unit 3 accommodated in each accommodating portion 24 is also helically twisted along the axial direction of the optical cable 1 . A plurality of optical units 3 may be bundled and twisted together. Thus, since the optical unit 3 is helically twisted along the axial direction of the optical cable 1, the bending loss of the optical fiber core wire 31 included in the optical unit 3 is sufficiently reduced when the optical cable 1 is bent. It is possible to

A plurality of optical units 3 are housed in each housing portion 24 of the spacer 2 . Each optical unit 3 has a plurality of optical fiber ribbons 30 . Each optical fiber tape core wire 30 has a plurality of optical fiber core wires 31 arranged in parallel. The optical fiber tape core wire 30 is, for example, an intermittent bonding type optical fiber tape core wire in which adjacent optical fiber core wires among a plurality of optical fiber core wires arranged in parallel are intermittently bonded along the axial direction. may be In each optical unit 3, a plurality of optical fiber ribbons 30 may be helically twisted along the axial direction.

The optical fiber core wire 31 has a glass fiber and a resin coating covering the glass fiber. A glass fiber has at least one core through which signal light propagates and a clad covering the core. The refractive index of the core is greater than that of the cladding.

In this example, each optical fiber tape core wire 30 has 12 optical fiber core wires 31 . Each optical unit 3 has 18 optical fiber ribbons 30 . Furthermore, 32 optical units 3 are housed in each of the two housings 24 . The number of optical fiber core wires 31 mounted in the optical cable 1 is merely an example, and any number of optical fiber core wires 31 may be mounted in the optical cable 1 . For example, 1000 or more optical fibers 31 may be mounted in the optical cable 1 .

The non-woven fabric tape 4 is wound around a bundle of a plurality of optical units 3 housed in each housing section 24, and functions as a pressure winding tape. Moreover, although not shown in FIG. 2, a bundle of the plurality of optical units 3 may be wound with a coarse winding thread. The sheath 5 constitutes the outer surface of the optical cable 1 and covers the spacer 2 , the plurality of optical units 3 and the non-woven fabric tape 4 . The sheath 5 is made of, for example, a resin material such as polyethylene or polyvinyl chloride, and functions as a protective layer that imparts weather resistance, heat resistance, and water resistance to the optical cable 1 .

Next, a method for manufacturing the optical cable 1 will be described below with reference to FIGS. 2 to 4. FIG. FIG. 3 is a flowchart for explaining the method for manufacturing the optical cable 1 according to this embodiment. FIG. 4 is a diagram schematically showing a manufacturing facility 100 for the optical cable 1 according to this embodiment.

As shown in FIG. 4, the manufacturing equipment 100 for the optical cable 1 includes a supply drum 101, a conveying roller 105, a supply bobbin 102, a grouped mesh plate 120, a rough yarn supplier 103, a tape supplier 107, A transport roller 106 and a winding drum 104 are provided. The spacer 2 shown in FIG. 1 is wound around the supply drum 101 .

As shown in FIG. 3, first, in step S1, the spacers 2 shown in FIG. In the spacer 2 wound around the supply drum 101, the pair of ribs 23 (or the housing portion 24) are not twisted along the axial direction of the spacer 2, but extend parallel to the axial direction. In other words, the positions of the pair of ribs 23 (or the housing portions 24) on the cross section of the spacer 2 perpendicular to the axial direction are fixed without continuously changing along the axial direction.

Next, in step S<b>2 , the spacers 2 supplied from the supply drum 101 are transported to the collective grid plate 120 by the transport rollers 105 . After that, the plurality of optical units 3 supplied from the supply bobbins 102 are accommodated in the respective accommodating portions 24 of the spacer 2 in the collective grid plate 120 . In this example, 32 optical units 3 are accommodated in each of the two accommodation portions 24 in the collective grid plate 120 . Also, the number of supply bobbins 102 is provided according to the number of optical units 3 . In this example, 64 optical units 3 are housed in the housing portion 24 of the spacer 2 , so 64 supply bobbins 102 are installed in the manufacturing facility 100 .

As described above, since the pair of ribs 23 extends parallel to the axial direction of the spacer 2 without being twisted, the positions of the accommodating portions 24 of the spacer 2 are constant along the axial direction. For this reason, in this embodiment, when a plurality of optical units 3 are accommodated in each accommodating portion 24, the supply drum 101 and the winding drum are arranged around the central axis Ax of the spacer 2 so as to correspond to the twist pitch of the accommodating portion 24. There is no need to rotate 104 synchronously.

Next, after the plurality of optical units 3 are accommodated in the accommodation portions 24 of the spacer 2 in the grouped grid plate 120, the spacer body 20 is twisted in step S3. In this respect, by rotating only the winding drum 104 around the central axis Ax of the spacer 2, the spacer body 20 can be twisted at a predetermined twist pitch. The twist pitch of the spacer body 20 is, for example, between 600 mm and 2000 mm.

Also, since the adhesion between the spacer body 20 and the tension member 22 is weak, the spacer body 20 is twisted along the axial direction, while the tension member 22 is not twisted along the axial direction. In step S<b>4 , the spacer body 20 is helically twisted along the axial direction by the winding drum 104 while the spacer body 20 is peeled off from the tension member 22 .

Next, in step S4, after the coarse thread is wound around the bundle of optical units 3 accommodated in each accommodation portion 24 of the spacer 2, the non-woven fabric tape 4 is wound around the bundle of optical units 3. As shown in FIG. The rough winding yarn is supplied from the rough winding yarn supplier 103 and the non-woven fabric tape 4 is supplied from the tape supplier 107 . After that, in step S5, the spacer 2 containing the optical unit 3 is wound up by the winding drum 104. As shown in FIG. Finally, in step S6, the sheath 5 is formed around the spacer 2 so as to cover the spacer 2, the optical unit 3, and the non-woven fabric tape 4. As shown in FIG. Thus, the optical cable 1 is manufactured. A sheath forming device for forming the sheath 5 is not shown in FIG. Also, the sheath 5 may be formed around the outer circumference of the spacer 2 before the spacer 2 is wound by the winding drum 104 .

(Effects of spacer 2 and optical cable 1 according to this embodiment)
According to the present embodiment, the spacer 2 has two ribs 23, so that the cross-sectional area of the spacer 2 in the cross section perpendicular to the axial direction (Z-axis direction) of the optical cable 1 is reduced as shown in FIG. . For this reason, the mountable area of the optical fiber core wire 31 mounted on the optical cable 1 in the cross section perpendicular to the axial direction of the optical cable 1 increases. Here, the mountable area of the optical fiber core wire 31 is obtained by subtracting the cross-sectional area of the spacer 2 from the area of the circle (πR ² ) calculated from the outer diameter R of the spacer 2 (see FIG. 2). Also, the mounting density of the optical fiber core wires 31 is obtained by dividing the actual mounting area of the optical fiber core wires 31 by the mountable area of the optical fiber core wires 31 .

In this way, by reducing the cross-sectional area of the spacer 2, the mountable area of the optical fiber core wires 31 is increased. While reducing the diameter of the optical fiber cable 1, the apparent mounting density of the optical fiber core wires 31 mounted on the optical cable 1 can be reduced. Specifically, even if the number of optical fibers 31 mounted on the optical cable 1 is 1000 or more and the outer diameter R of the spacer 2 is 40 mm or less, the reduction in the cross-sectional area of the spacer 2 reduces the light The mounting density of the fiber core wires 31 can be apparently reduced. As a result, it is possible to preferably prevent an increase in transmission loss of the optical fiber core wire 31 included in the optical unit 3 due to the adjacent optical units 3 mounted in the optical cable 1 pushing each other. In particular, when the packing density of the optical fiber core wires is 50% or more and 60% or less, the standard value of the transmission loss of the optical fiber core wires 31, which is 0.3 dB, is maintained while maintaining the high packing density of the optical fiber core wires 31. /km can be satisfied.

Further, the tension member 22 is positioned at the center of the spacer 2 and a pair of ribs 23 are arranged point-symmetrically with respect to the central axis Ax of the tension member 22 . Therefore, the tendency of the optical cable 1 to bend in a predetermined direction is preferably prevented, and the handling of the optical cable 1 is improved.

Therefore, in the present embodiment, the optical characteristics of the optical fibers 31 mounted on the optical cable 1 are reduced while reducing the diameter of the optical cable 1 without reducing the number of the optical fibers 31 mounted on the optical cable 1. Preventable spacers 2 and optical cables 1 can be provided.

Moreover, since the pair of ribs 23 are arranged on the same straight line in the X-axis direction, the height dimension of the spacer 2 in the Y-axis direction is reduced. Therefore, it is possible to wind a larger amount of spacers 2 onto the drum. Furthermore, from the viewpoint of miniaturization of the optical cable 1, the length of each of the pair of ribs 23 in the X-axis direction is set to 5 mm or more and 20 mm or less. The thickness of the pair of ribs 23 in the Y-axis direction is set to 0.5 mm or more and 2 mm or less from the viewpoint of the mounting density of the optical fiber core wires 31 and the strength of the spacer 2 . In particular, when the thickness of the rib 23 is 0.5 mm or more and 2 mm or less, the packing density of the optical fibers 31 mounted on the optical cable 1 can be reduced while maintaining the strength of the spacer 2 .

(Modification of this embodiment)
Next, a spacer 2a according to a modified example of the present embodiment and an optical cable 1a including the spacer 2a will be described below with reference to FIGS. 5 and 6. FIG. FIG. 5 is a cross-sectional view showing a spacer 2a according to a modification of this embodiment. FIG. 6 is a cross-sectional view showing an optical cable 1a according to a modification of this embodiment. The cross section of the spacer 2a shown in FIG. 5 and the cross section of the optical cable 1a shown in FIG. 6 are perpendicular to the Z-axis direction. In the following, members having the same reference numbers as those already described in this embodiment will not be repeatedly described.

As shown in FIG. 5, the spacer 2a includes a tension member 22a made of high tension material and a spacer main body 20a made of hard resin material. The spacer body 20a is configured to cover the tension member 22a. The spacer body 20a has a central portion 21a surrounding the tension member 22a and a pair of ribs 23a extending outward from the central portion 21a.

The spacer main body 20a covers the tension member 22a in a state in which the adhesion between the tension member 22a and the spacer main body 20a is weak. The pair of ribs 23a protrude outward from the central portion 21a and extend parallel to each other without spirally twisting along the axial direction (Z-axis direction) of the spacer 2a. The pair of ribs 23a are integrally formed with the central portion 21a. Also, the pair of ribs 23a are arranged point-symmetrically with respect to the central axis Ax of the tension member 22a (or the spacer 2a) in a cross section perpendicular to the axial direction of the spacer 2a. In particular, one of the pair of ribs 23a protrudes outward from the central portion 21a so as to be curved in a U shape, while the other of the pair of ribs 23a is projected outward from the central portion so as to be curved in an inverted U shape. It protrudes outward from 21a. Thus, the pair of ribs 23a are formed in an S shape in the cross section of the spacer 2 perpendicular to the axial direction.

Next, as shown in FIG. 6, the optical cable 1a includes a spacer 2a, a plurality of optical units 3, a non-woven fabric tape 4, and a sheath 5. As shown in FIG. The pair of ribs 23a defines two housing portions 24a in which the optical unit 3 is housed. Each housing portion 24a is twisted, for example, in a spiral shape by being twisted along the axial direction of the spacer 2a. Since each accommodating portion 24a is helically twisted along the axial direction of the spacer 2, the optical unit 3 accommodated in each accommodating portion 24a is also helically twisted along the axial direction of the optical cable 1a. In this modified example, the spacer 2a is similarly twisted in a spiral shape along the axial direction by the winding drum 104 in the manufacturing process of the optical cable 1a.

In this modification, since the pair of ribs 23a are formed in an S shape in the cross section of the spacer 2a perpendicular to the Z-axis direction, a plurality of light beams are stored in the two housing portions 24a defined by the pair of ribs 23a. It becomes easier to accommodate the unit 3. In particular, each of the pair of ribs 23a is curved, and the optical unit 3 is supported by the curved portion of each rib 23a. In this manner, the large number of optical units 3 housed in the housing portion 24a can be reliably bundled with the coarsely wound thread and the non-woven fabric tape 4. As shown in FIG.

Although the present embodiment has been described above, it goes without saying that the technical scope of the present invention should not be limitedly interpreted by the description of the embodiment. It is understood by those skilled in the art that this embodiment is merely an example, and that various modifications of the embodiment are possible within the scope of the invention described in the claims. Thus, the technical scope of the present invention should be determined based on the scope of the invention described in the claims and their equivalents.

1, 1a: Optical cable 2, 2a: Spacer 3: Optical unit 4: Non-woven fabric tape 5: Sheath 20, 20a: Spacer body 21, 21a: Center part 22, 22a: Tension member 23, 23a: Rib 24, 24a: Accommodating part 30: Optical fiber tape core wire 31: Optical fiber core wire 101: Supply drum 102: Supply bobbin 103: Rough winding yarn supplier 104: Winding drum 105: Conveyor roller 106: Conveyor roller 107: Tape supplier 120: Collecting stitches board

Claims (7)

a tension member;
a spacer body covering the tension member;
A spacer comprising
The spacer body is
a central portion surrounding the tension member;
a pair of ribs projecting outward from the central portion and extending in the axial direction of the spacer without being twisted;
has
The pair of ribs are arranged point-symmetrically with respect to the central axis of the tension member,
Spacer. In a cross section perpendicular to the axial direction of the spacer, the pair of ribs are arranged on the same straight line,
2. Spacer according to claim 1. The pair of ribs are formed in an S shape in a cross section perpendicular to the axial direction of the spacer,
2. Spacer according to claim 1. Each length of the pair of ribs is 5 mm or more and 20 mm or less,
The thickness of each of the pair of ribs is 0.5 mm or more and 2 mm or less.
4. A spacer according to any one of claims 1-3. A spacer according to any one of claims 1 to 4;
a plurality of optical fiber core wires;
a sheath that covers the spacer and the plurality of optical fiber core wires;
An optical cable comprising
The optical cable is formed in a circular shape in a cross section perpendicular to the axial direction of the optical cable,
optical cable. The outer diameter of the spacer is 40 mm or less, and the number of optical fiber core wires mounted in the optical cable is 1000 or more.
The optical cable according to claim 5. A mounting density of the optical fiber core wire mounted on the optical cable is 50% or more and 60% or less,
The optical cable according to claim 5 or 6.

Images