JP2004198588A - Optical fiber cable - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical fiber cable that is easy to bend, hard to buckle, and enables force-in laying. <P>SOLUTION: Since a plurality of linear bodies 18 and 19 are stranded to constitute a tension member 12 and a support wire 17, the tension member 12 and the support wire 17 are highly rigid, easy to bend and hardly have bending inclination. Thus, one coated optical fiber 11 and a tape ribbon forming a plurality of coated optical fibers 20 in the form of a tape, or an optical unit 22 collecting a plurality of the coated optical fibers 20 and the optical fiber cables 10A, 10B, 10C, 10D and 10E constituted by covering a skin 13 around the tension member 12 and the support wire 17, for instance, are easy to bend to curvature of a laying pipe path, and since they hardly have bending inclination, force-in laying is enabled. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an optical fiber cable.
[0002]
[Prior art]
Conventional optical fiber cables include those shown in FIGS. 7 and 8 (for example, see Patent Document 1).
The optical fiber cable 100 shown in FIG. 7 is mainly used as a drop cable from an underground cable. In this optical fiber cable 100, an optical fiber core wire 101 is arranged at the center. Tension members 102 and 102 made of a single-wire steel wire are arranged on both left and right sides of the optical fiber core wire 101, and the periphery thereof is collectively covered with an outer cover 103. Accordingly, the tension applied to the optical fiber cable 100 is borne by the two tension members 102, 102, so that the optical fiber core wire 101 can be protected from external force. Notches 104 are provided at the upper and lower positions in the center of the outer cover 103 so that the outer cover 103 can be easily torn when the optical fiber 101 is taken out.
[0003]
An optical fiber cable 110 as shown in FIG. 8 is mainly used as a drop cable from an overhead cable. In FIG. 7, the same reference numerals are given to portions common to the above-described optical fiber cable 100, and redundant description will be omitted.
In this optical fiber cable 110, an optical fiber cable main body 111 having the same structure as the optical fiber cable 100 described above with reference to FIG. 7 is covered together with a support wire 113 made of a single-wire steel wire via a connecting portion 112. is there. The connecting portion 112 is formed thin, so that the support wire 113 side and the optical fiber cable main body 111 can be easily separated.
[0004]
[Patent Document 1]
Japanese Patent Application Laid-Open No. 2000-171673 (page 2, FIG. 1)
[0005]
[Problems to be solved by the invention]
By the way, when laying a drop cable or indoor cable composed of the optical fiber cables 100 and 110 as described above in a pipeline, a wire rod or the like is previously passed through the pipeline. Then, it is common to tie a drop cable or the like to the wire rod or the like and pull the wire rod or the like to lay the cable. For this reason, it is necessary to preliminarily carry out the work of passing the passage rod or the like into the pipeline, which requires a long working time.
[0006]
Therefore, if the drop cable or the indoor cable can be directly laid in the pipeline and laid, it is possible to save the time and labor required for previously passing the wiring rod into the pipeline, and to shorten the working time.
[0007]
However, a single-wire steel wire is generally used for the tension member 102 of the optical fiber cable 100 and the support wire 113 of the optical fiber cable 110. For this reason, when the optical fiber cables 100 and 110 are pushed into the pipeline as described above, at the place where the pipeline is bent, the rigidity of the tension member 102 and the support wire 113 corresponds to the bending of the pipeline. There is a problem that the optical fiber cables 100 and 110 cannot be laid because they are not bent. Conversely, when the rigidity of the tension member 102 or the support wire 113 is low, there is a problem that the tension member 102 and the support wire 113 meander during the push-in installation. Further, if the tension member 102 and the support wire 113 are bent in accordance with the bending of the pipeline, there is a problem that a habit is formed in the bent state, and the buckling may be caused by the subsequent pushing.
[0008]
The present invention has been made in view of the above-described problems, and an object of the present invention is to provide an optical fiber cable which is easy to bend, is hardly buckled, and can be pushed and laid.
[0009]
[Means for Solving the Problems]
In order to achieve the above-mentioned object, an optical fiber cable according to the present invention has a tape core in which one optical fiber core and a plurality of optical fiber cores are formed in a tape shape. An optical fiber cable in which a sheath is coated around a wire, or an optical unit in which a plurality of optical fiber cores are assembled, and a tension member,
The tension member is formed by twisting a plurality of linear bodies.
[0010]
In the optical fiber cable configured as described above, since the tension member is formed by twisting the linear member, the tension member has high rigidity and is easy to bend, but hard to bend. For this reason, one optical fiber core, a tape core obtained by forming a plurality of optical fiber cores in a tape shape, or an optical unit in which a plurality of optical fiber cores are assembled, and the tension member described above. The optical fiber cable constructed by integrally covering the outer skin around the optical fiber can be easily bent and hardly bent, for example, in accordance with the bending of the pipeline to be laid.
[0011]
Further, the optical fiber cable according to the present invention is, as described in claim 2, a single optical fiber core, a tape core in which a plurality of optical fiber cores are formed in a tape shape, or a plurality of cores. An optical unit in which optical fiber cores are gathered, and an optical fiber cable in which a sheath is coated around a support wire,
The support wire is formed by twisting a plurality of linear bodies.
[0012]
In the optical fiber cable configured as described above, since the supporting wire is formed by twisting the linear body, the supporting wire has high rigidity and is easy to bend, but hard to bend. For this reason, one optical fiber core, a tape core in which a plurality of optical fiber cores are formed in a tape shape, or an optical unit in which a plurality of optical fiber cores are aggregated, The optical fiber cable constructed by integrally covering the outer skin around the optical fiber can be easily bent and hardly bent, for example, in accordance with the bending of the pipeline to be laid.
[0013]
Further, the optical fiber cable according to the present invention is, as described in claim 3, a single optical fiber core, a tape core in which a plurality of optical fiber cores are formed in a tape shape, or a plurality of cores. An optical unit in which optical fiber cores are assembled, a tension member, and an optical fiber cable in which an outer sheath is coated around a support wire,
The tension member and the support wire are formed by twisting a plurality of linear bodies.
[0014]
In the optical fiber cable thus configured, since the tension member and the support wire are formed by twisting the linear body, the rigidity of the tension member and the support wire is high, and the tension member and the support wire are easy to bend but hard to bend. It becomes. For this reason, one optical fiber core, a tape core in which a plurality of optical fiber cores are formed in a tape shape, or an optical unit in which a plurality of optical fiber cores are assembled, the tension member described above, In an optical fiber cable constructed by covering the outer skin integrally around the support wire, it is easily bent, for example, in accordance with the bending of the pipeline to be laid, and is hard to bend. Become.
[0015]
Further, the optical fiber cable according to the present invention is, as described in claim 4, in the optical fiber cable according to any one of claims 1 to 3, wherein the linear body is a steel wire. Features.
[0016]
In the optical fiber cable configured as described above, since the tension member and the support wire are configured by twisting a steel wire, the twisted wire processing is easy and a desired strength can be obtained.
[0017]
The optical fiber cable according to the present invention is, as described in claim 5, in the optical fiber cable according to any one of claims 1 to 3, wherein the linear body is a fiber-reinforced plastic. It is characterized by.
[0018]
In the optical fiber cable thus configured, since the tension members and the support wires are formed by twisting the fiber reinforced plastic which is an electrically insulating material, it is possible to prevent lightning damage and electric shock due to electromagnetic induction. become.
[0019]
The optical fiber cable according to the present invention is, as described in claim 6, in the optical fiber cable according to any one of claims 1 to 5, wherein the diameter of the stranded wire is 1.0 mm to 4 mm. It is characterized by a range of 0.5 mm.
[0020]
In the optical fiber cable configured as described above, the diameter of the stranded wire is set in the range of 1.0 mm to 4.5 mm, so that the stranded wire workability is good. On the other hand, if the diameter is 1.0 mm or less, the rigidity is low, so that push-in installation cannot be performed. On the other hand, when the diameter is 4.5 mm or more, the rigidity is too high, so that the optical fiber cable is difficult to bend, and it is difficult to lay the cable.
[0021]
In addition, the optical fiber cable according to the present invention, as described in claim 7, in the optical fiber cable according to any one of claims 1 to 6, the stranded wire is a three linear body. It is characterized by being twisted.
[0022]
In the optical fiber cable configured as described above, since the tension member and the support wire are formed by twisting three linear bodies, the positions of the respective linear bodies are stabilized, and the strands are stabilized. As a result, a firm optical fiber cable can be obtained.
[0023]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of an optical fiber cable according to the present invention will be described in detail with reference to the drawings. FIG. 1 is a sectional view of the optical fiber cable according to the first embodiment, and FIG. 2 is a perspective view of a stranded wire.
[0024]
As shown in FIG. 1, in an optical fiber cable 10A which is a first embodiment of the optical fiber cable according to the present invention, a single optical fiber core wire 11 is arranged at the center. Tension members 12 made of a steel wire having a single wire diameter of, for example, 0.4 mm are arranged on both upper and lower sides of the optical fiber core 11 in FIG. The optical fiber cable main body 14 is formed by coating with an outer cover 13 made of the same.
[0025]
Thus, the tension member 12 bears the tension applied to the optical fiber cable 10A, so that the optical fiber core 11 can be protected from external force. A notch portion 15 is provided at a position outside the center of the outer cover 13, and by tearing the outer cover 13 from the notch portion 15, the optical fiber 11 can be easily taken out. .
[0026]
In addition, a support wire 17 having a stranded wire structure is collectively covered with an outer cover 13 on the optical fiber cable main body 14 via a connecting portion 16. As shown in FIG. 2, the support wire 17 is formed, for example, by twisting three steel wires 18 each having a diameter of 2 mm as a linear body and having an outer diameter of about 4.3 mm.
[0027]
The reason why the diameter of the support wire 17 which is a stranded wire falls within the range of 1.0 mm to 4.5 mm is that if the diameter is too large, it is difficult to bend. This is because it is not possible to cope with the bent portion, and it becomes impossible to perform push-in laying. In addition, if the outer diameter of the optical fiber cable 10A is increased or the mass is increased, it exceeds the weight that can be carried by one worker. On the other hand, if the diameter is too small, the rigidity is too small, and the wire may be caught at a bent portion in the pipeline, and buckling may occur when the wire is further pushed. And The connecting portion 16 is formed thin, so that the support wire 17 side and the optical fiber cable main body 14 can be easily separated.
[0028]
As described above, according to the above-mentioned optical fiber cable 10A, since the support wire 17 is formed by twisting the three steel wires 18, the support wire 17 has high rigidity and is easy to bend, but hardly bends. Become. For this reason, the optical fiber cable 10A is easily bent, for example, in accordance with the bending of the pipe line to be laid, and is hard to bend, so that push-in laying is possible. In particular, since the support wires 17, which are stranded wires, are formed by the three steel wires 18, each steel wire 18 is always in contact with all other steel wires 18, and a stable stranded wire can be formed.
[0029]
Moreover, since the support wire 17 is formed by twisting the steel wire 18, the twisted wire processing is easy and the desired strength can be easily obtained. In addition, since the diameter of the support wire 17 that is a stranded wire is in the range of 1.0 mm to 4.5 mm, the workability of the stranded wire is good, and the push-in installation work can be easily performed.
[0030]
Next, a second embodiment of the optical fiber cable according to the present invention will be described in detail with reference to the drawings. The same parts as those in the first embodiment described above are denoted by the same reference numerals, and redundant description will be omitted. FIG. 3 is a cross-sectional view of the optical fiber cable according to the second embodiment.
[0031]
As shown in FIG. 3, in this optical fiber cable 10B, a single optical fiber core wire 11 is arranged at the center. Then, tension members 12 and 12 formed by twisting three steel wires 19 of, for example, φ2 mm, which are linear bodies, are arranged on both upper and lower sides of the optical fiber core 11 in FIG. Then, the optical fiber cable 10B is formed by coating with an outer cover 13 made of, for example, PE resin. As shown in FIG. 2, the tension member 12 is formed, for example, by twisting three φ2 mm steel wires 19 to have an outer diameter of about 4.3 mm.
[0032]
Thus, the reason why the diameter of the tension member 12, which is a stranded wire, is in the range of 1.0 mm to 4.5 mm is that if the diameter is too large, it is difficult to bend. This is because it becomes impossible to perform push-in laying. In addition, if the outer diameter of the optical fiber cable 10A is increased or the mass is increased, it exceeds the weight that can be carried by one worker. On the other hand, if the diameter is too small, the rigidity is too small, and the wire may be caught at a bent portion in the pipeline, and buckling may occur when the wire is further pushed. And
[0033]
Thus, the tension member 12 bears the tension applied to the optical fiber cable 10B, so that the optical fiber core 11 can be protected from external force. A notch portion 15 is provided at a position outside the center of the outer cover 13, and by tearing the outer cover 13 from the notch portion 15, the optical fiber 11 can be easily taken out. .
[0034]
As described above, according to the above-described optical fiber cable 10B, since the tension member 12 is formed by twisting the three steel wires 19, the tension member 12 has high rigidity and is easy to bend, but hardly bends. Become. For this reason, the optical fiber cable 10B is easily bent, for example, in accordance with the bending of the pipe line to be laid, and is unlikely to be bent, so that push-in laying is possible. In particular, since the tension members 12 which are stranded wires are formed by the three steel wires 19, each steel wire 19 is always in contact with all other steel wires 19, and a stable stranded wire can be formed.
[0035]
In addition, since the tension member 12 is formed by twisting the steel wire 19, stranded wire processing is easy and desired strength can be easily obtained. In addition, since the diameter of the tension member 12, which is a stranded wire, is in the range of 1.0 mm to 4.5 mm, the stranded wire workability is good, and the push-in laying operation can be easily performed.
[0036]
Next, a third embodiment of the optical fiber cable according to the present invention will be described in detail with reference to the drawings. In addition, the same reference numerals are given to portions common to the above-described first and second embodiments, and overlapping description will be omitted. FIG. 4 is a sectional view of the optical fiber cable according to the third embodiment.
As shown in FIG. 4, in this optical fiber cable 10C, a single optical fiber core wire 11 is arranged at the center. As shown in FIG. 2, tension members 12, 12 of about φ4.3 mm formed by twisting three φ2 mm steel wires 19 are provided on both upper and lower sides of the optical fiber core 11 in FIG. 4. At the same time, the optical fiber cable main body 14 is formed by covering the periphery of the optical fiber cable 13 with an outer skin 13 made of, for example, PE resin.
[0037]
Thus, the tension member 12 bears the tension applied to the optical fiber cable 10C, so that the optical fiber core 11 can be protected from external force. A notch portion 15 is provided at a position outside the center of the outer cover 13, and by tearing the outer cover 13 from the notch portion 15, the optical fiber 11 can be easily taken out. .
[0038]
In addition, a support wire 17 having a stranded wire structure is collectively covered with an outer cover 13 on the optical fiber cable main body 14 via a connecting portion 16. The connecting portion 16 is formed thin, so that the support wire 17 side and the optical fiber cable main body 14 can be easily separated. Further, as shown in FIG. 2, the support wire 17 is formed by twisting three steel wires 18 of, for example, φ2 mm.
[0039]
The reason why the diameters of the tension member 12 and the support wire 17 which are stranded wires are in the range of 1.0 mm to 4.5 mm is that if the diameter is too large, it is difficult to bend, so that the bent portion of the pipeline is formed. This is because it is not possible to cope with this and it becomes impossible to perform push-in laying. In addition, if the outer diameter of the optical fiber cable 10A is increased or the mass is increased, it exceeds the weight that can be carried by one worker. On the other hand, if the diameter is too small, the rigidity is too small, and the wire may be caught at a bent portion in the pipeline, and buckling may occur when the wire is further pushed. And
[0040]
As described above, according to the optical fiber cable 10C, the tension member 12 is formed by twisting the three steel wires 19, and the support wire 17 is formed by twisting the three steel wires 18; The support wire 12 and the support wire 17 have high rigidity and are easy to bend, but hard to bend. For this reason, the optical fiber cable 10 is easily bent, for example, in accordance with the bending of the pipe line to be laid, and is hard to bend, so that push-in laying is possible. In particular, since the tension member 12 and the support wire 17, which are stranded wires, are constituted by the three steel wires 19, 18, each of the steel wires 19, 18 always comes in contact with all the other steel wires 19, 18, and is stable. Stranded wire can be configured.
[0041]
Further, since the tension members 12 and the support wires 17 are formed by twisting the steel wires 19 and 18, the twisted wire processing is easy and the desired strength can be easily obtained. Further, since the diameter of the stranded wire is in the range of 1.0 mm to 4.5 mm, the stranded wire workability is good, and the push-in laying operation can be easily performed.
[0042]
Next, a fourth embodiment of the optical fiber cable according to the present invention will be described in detail with reference to the drawings. In addition, the same reference numerals are given to portions common to the above-described first to third embodiments, and redundant description will be omitted. FIG. 5 is a sectional view of the optical fiber cable according to the fourth embodiment.
As shown in FIG. 5, in this optical fiber cable 10D, a tape core 21 in which a plurality of (here, two) optical fiber cores 20 are formed in a tape shape is disposed at the center. Then, the tension member 12 formed by twisting three steel wires 19 of, for example, φ2 mm is disposed on one of the right and left sides of the tape core wire 21 in FIG. An optical fiber cable 10D is formed by covering the whole with an outer cover 13 made of resin or the like in an elliptical or elliptical shape. A notch portion 15 is provided in the outer peripheral portion of the central portion, so that the tape core wire 21 can be easily taken out.
[0043]
Even with such a configuration, it is possible to obtain the same operational effects as in the above-described embodiment.
[0044]
Next, a fifth embodiment of the optical fiber cable according to the present invention will be described in detail with reference to the drawings. In addition, the same reference numerals are given to portions common to the above-described first to fourth embodiments, and redundant description will be omitted. FIG. 6 is a sectional view of the optical fiber cable according to the fifth embodiment.
As shown in FIG. 6, in the optical fiber cable 10E, an optical unit 22 in which a plurality of optical fiber cores 20 are gathered at the center is arranged. Then, in FIG. 6 of the optical unit 22, the tension members 12 formed by twisting three steel wires 19 of, for example, φ2 mm are arranged on both upper and lower sides, and the periphery thereof is collectively made of, for example, PE resin. An optical fiber cable 10E is formed by covering the whole with the outer cover 13. Notches 15 are provided on both left and right sides of the central portion, so that the optical unit 22 can be easily taken out.
[0045]
Even with such a configuration, it is possible to obtain the same operational effects as in the above-described embodiment.
[0046]
In addition, the optical fiber cables 10A, 10B, 10C, 10D, and 10E of the present invention are not limited to the above-described embodiments, and appropriate modifications and improvements can be made.
For example, in each of the above-described embodiments, the tension member 12 and the support wire 17 which are stranded wires are constituted by the steel wires 19 and 18. In addition, fiber reinforced plastic (FRP) or stainless steel is used as the linear body. You can also.
Further, in each of the above-described embodiments, the stranded wire is configured by three linear bodies, but is not limited thereto. For example, it is possible to use two or more linear bodies, such as seven strands.
Further, in the optical fiber cable 10D according to the fourth embodiment including the tape core 21 illustrated in FIG. 5 and the optical fiber cable 10E according to the fifth embodiment including the optical unit 22 illustrated in FIG. A line may be provided. In this case, the support wire may be a single-wire steel wire or a stranded wire composed of a plurality of steel wires.
[0047]
【The invention's effect】
As described above, according to the optical fiber cable according to the present invention, as described in claim 1, the tension member is formed by twisting the linear body, so that the tension member has high rigidity and is bent. It is easy, but hard to bend. For this reason, one optical fiber core, a tape core obtained by forming a plurality of optical fiber cores in a tape shape, or an optical unit in which a plurality of optical fiber cores are assembled, and the tension member described above. In the optical fiber cable constructed by covering the outer periphery with the outer sheath, for example, the optical fiber cable is easily bent in accordance with the bending of the pipeline to be laid, and is hard to bend, so that push-in laying is possible.
[0048]
In addition, as described in claim 2, since the support wire is formed by twisting the linear body, the support wire has high rigidity and is easy to bend, but hard to bend. For this reason, one optical fiber core, a tape core in which a plurality of optical fiber cores are formed in a tape shape, or an optical unit in which a plurality of optical fiber cores are aggregated, In the optical fiber cable constructed by covering the outer periphery with the outer sheath, for example, the optical fiber cable is easily bent in accordance with the bending of the pipeline to be laid, and is hard to bend, so that push-in laying is possible.
[0049]
Further, as described in claim 3, since the tension member and the support wire are formed by twisting the linear body, the rigidity of the tension member and the support wire is high, and the tension member and the support wire are easy to bend but hard to bend. Become. For this reason, one optical fiber core, a tape core in which a plurality of optical fiber cores are formed in a tape shape, or an optical unit in which a plurality of optical fiber cores are assembled, the tension member described above, In an optical fiber cable constituted by covering the outer circumference around the support wire, the optical fiber cable is easily bent, for example, in accordance with the bending of the pipeline to be laid, and is hard to bend, so that push-in laying is possible.
[Brief description of the drawings]
FIG. 1 is a sectional view showing a first embodiment of an optical fiber cable according to the present invention.
FIG. 2 is an enlarged perspective view of a stranded wire.
FIG. 3 is a sectional view showing a second embodiment of the optical fiber cable according to the present invention.
FIG. 4 is a sectional view showing a third embodiment of the optical fiber cable according to the present invention.
FIG. 5 is a sectional view showing a fourth embodiment of the optical fiber cable according to the present invention.
FIG. 6 is a sectional view showing a fifth embodiment of the optical fiber cable according to the present invention.
FIG. 7 is a cross-sectional view showing an example of a general optical fiber cable from the related art.
FIG. 8 is a cross-sectional view showing another example of an optical fiber cable that is more common than a conventional one.
[Explanation of symbols]
10A, 10B, 10C, 10D, 10E Optical fiber cable 11, 20 Optical fiber core 12 Tension member 13 Outer skin 17 Supporting wire 18, 19 Steel wire (linear body)
21 Tape ribbon 22 Optical unit

Claims (7)

An outer sheath is provided around a single optical fiber core, a tape core obtained by forming a plurality of optical fiber cores in a tape shape, or an optical unit in which a plurality of optical fiber cores are assembled, and a tension member. A coated optical fiber cable,
An optical fiber cable, wherein the tension member is formed by twisting a plurality of linear bodies. One optical fiber core, a tape core in which a plurality of optical fiber cores are formed in a tape shape, or an optical unit in which a plurality of optical fiber cores are gathered, and a sheath around the support wire. A coated optical fiber cable,
An optical fiber cable, wherein the support wire is formed by twisting a plurality of linear bodies. One optical fiber core, a tape core obtained by forming a plurality of optical fiber cores in a tape shape, or an optical unit in which a plurality of optical fiber cores are assembled, a tension member, and a support wire. An optical fiber cable having an outer skin covered therewith,
An optical fiber cable, wherein the tension member and the support wire are formed by twisting a plurality of linear bodies. The optical fiber cable according to any one of claims 1 to 3, wherein the linear body is a steel wire. The optical fiber cable according to any one of claims 1 to 3, wherein the linear body is a fiber reinforced plastic. The optical fiber cable according to any one of claims 1 to 5, wherein a diameter of the stranded wire is in a range of 1.0 mm to 4.5 mm. The optical fiber cable according to any one of claims 1 to 6, wherein the stranded wire is formed by twisting three linear bodies.

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