JP3869140B2 - Tape structure wound optical fiber cable and overhead wire around which the optical fiber cable is wound - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a tape-structure wound optical fiber cable wound around an overhead wire such as an overhead ground wire, an overhead power transmission line (power line), a distribution line, and a structure for winding the optical fiber cable around the overhead wire. About.
[0002]
[Prior art]
There are two methods for laying an optical fiber cable using an overhead wire: a built-in type in which the optical fiber core wire is built in the overhead wire, and a winding type in which the optical fiber cable is wound around the outer circumference of the overhead wire. The optical fiber cable (optical fiber core wire) laid in this way is widely used for transmitting information necessary for monitoring and controlling the power system.
By the way, the built-in type is one in which an optical unit 51 is arranged inside an aerial ground wire 54 as shown in FIG. In the optical unit 51, an optical fiber core 24 in which an optical fiber 22 is covered with a silicon resin 23 is disposed in a recess 53 provided in a spacer 52, and the whole is protected by an aluminum tube 55.
This built-in type is difficult to install in (1) existing overhead wires (such as overhead ground wires), and (2) the aluminum tube 55 that protects the optical fiber core wire 24 is caused by slight wind vibration or galloping of the overhead wires. There is a problem that fatigue damage is easily caused, and when the fatigue damage occurs, water enters the portion, and in the winter season, the water may freeze and expand to break the optical fiber.
[0003]
On the other hand, the winding type is a type in which an optical fiber cable is spirally wound around the outer periphery of an overhead wire, and the optical fiber cable includes a plurality of optical fiber core wires 24 around a tension member 32 as shown in FIG. Are wound in a spiral shape, and the outer periphery of the optical fiber cable 21 having a circular cross section provided with a sheath 56 of fluororesin, or a plurality of optical fiber core wires 24 as shown in FIG. And a tape-like optical fiber cable 26 (Japanese Utility Model Laid-Open No. 61-167320) in which the sheath 25 is extruded and coated.
[0004]
[Problems to be solved by the invention]
However, the winding mold has the following problems.
In other words, (1) the optical fiber cable has a smooth and hard surface, so if the catenary angle between the spans (the angle of inclination of the overhead ground wire with respect to the horizontal direction) is large, the winding will slip or loosen on the overhead wire. As a result, transmission loss increases. (2) When the winding is loosened, snow wraps around the overhead wire along the twisted groove, applying an excessive bending stress to the optical fiber cable, twisting the optical fiber cable and increasing transmission loss. It may break and become unable to transmit. (3) The optical fiber will be damaged if a suspension machine for maintenance and inspection rides.
It is an object of the present invention to provide a tape-structure-wrapped optical fiber cable that can stably obtain good optical transmission and a structure for winding the optical fiber cable around an overhead wire.
[0005]
[Means for Solving the Problems]
According to the first aspect of the present invention, a soft and easily deformable adhesive layer is provided on the surface (lower surface) of the tape-shaped optical fiber cable in which a plurality of optical fiber cores are arranged on the same plane and the sheath is collectively covered with the overhead wire. A tape-structure wound optical fiber cable having a thickness of 0.3 to 3 mm.
[0006]
The invention according to claim 2 is the tape-structured optical fiber cable according to claim 1, wherein protective layers are provided on the upper surface and both side surfaces of the tape-shaped optical fiber cable.
[0007]
The invention according to claim 3 is characterized in that the winding surface of the adhesive layer around the overhead wire is formed in an arc shape in the width direction so that the entire surface is in contact with the overhead wire. It is a tape structure winding type optical fiber cable of description.
[0008]
The invention according to claim 4 is the tape structure wound optical fiber cable according to any one of claims 1, 2, and 3, wherein the adhesive layer is conductive or semiconductive.
[0009]
A fifth aspect of the present invention is an overhead wire around which the tape-structure-wound optical fiber cable according to any one of the first, second, third, and fourth aspects is wound , and the tape-structure-wound optical fiber cable is an overhead line you characterized by being wound in substantially fills the Yomizo of the overhead wire and the adhesive layer.
[0010]
The invention according to claim 6 is the overhead wire according to claim 5, wherein a plurality of the tape-structured optical fiber cables are wound in a spiral shape with the side surfaces being in close contact with each other. .
[0011]
According to a seventh aspect, according to claim 5, wherein a plurality of said tape structure winding type optical fiber cable is wound spirally spaced equidistantly in the circumferential direction It is an overhead line .
[0012]
The invention according to claim 8, wherein the tape structure winding type optical fiber cable relation of P / D = 9 to 40 to the overhead line (wherein P is winding pitch mm tape structure winding type optical fiber cable, The overhead wire according to any one of claims 5, 6, and 7, wherein D is wound so as to satisfy a diameter mm of the overhead wire .
[0013]
DETAILED DESCRIPTION OF THE INVENTION
In the optical fiber cable of the present invention, an adhesive layer is provided on the surface to be wound around the overhead wire, and the adhesive layer is soft and easily deformed, so that the twisted groove of the overhead wire is substantially filled and wound. The cable can be firmly fixed and wound around the overhead wire without moving with a little force, and the optical fiber cable does not loosen or shift, and transmission loss hardly occurs. Further, since the adhesive layer is soft and easily deformed, even when a suspension machine for maintenance and inspection rides, the load (external force) is absorbed by the adhesive layer, and the optical fiber is not damaged. The reason why the thickness of the adhesive layer is regulated to 0.3 to 3 mm is that the external force is not sufficiently absorbed when the thickness is less than 0.3 mm, and the winding workability is deteriorated when the thickness exceeds 3 mm.
If the tape-structured wound optical fiber cable 21 is narrow, a sufficient fixing force to the overhead wire may not be obtained. Therefore, the width is preferably 5 mm or more.
As the adhesive layer, butyl rubber, silicon rubber, EVA, or the like obtained by applying or impregnating an adhesive is used.
[0014]
In the present invention, if a protective layer is provided on the upper surface and both side surfaces of the tape-shaped optical fiber, the optical fiber cable can be protected from flying objects.
For the protective layer 40, ethylene propylene rubber (EPDM), silicon rubber, EVA, or the like is used.
[0015]
In the present invention, if the winding surface of the adhesive layer on the overhead wire is formed in an arc shape in the width direction so that the entire surface is in contact with the overhead wire, excess bending stress is applied to each optical fiber after winding. Does not act, and a highly reliable winding structure with small transmission loss is obtained.
[0016]
A gap (twisted groove portion) discharge may occur between the optical fiber cable and the overhead wire, and tracking or erosion may occur. The gap discharge is caused by making the adhesive layer conductive or semiconductive. Can be suppressed. The conductive or semiconductive adhesive layer can be obtained by mixing an appropriate amount of a conductive substance such as carbon powder or copper powder into the adhesive layer. Gap discharge is likely to occur in power lines to which high voltage is applied.
[0017]
If the tension member is combined with the adhesive layer, the optical fiber cable is prevented from being excessively stretched by the tension when the optical fiber cable is wound around the overhead wire.
As the tension member, sheet-like or fibrous glass, FRP, polypropylene, polyethylene, or the like is used.
[0018]
A taping machine or the like is used to wind the optical fiber cable according to the first to fourth aspects of the present invention around an overhead wire. In a taping machine, usually, a safe pressure that does not damage the optical fiber is continuously applied to the optical fiber cable, so that it sticks strongly to the overhead wire. When tension is applied and wound, the pressure-sensitive adhesive layer easily fills the twisted groove.
[0019]
When the optical fiber cable with a tape structure of the present invention is wound spirally around an overhead wire, convex portions are continuously formed on the overhead wire, so that wind noise is reduced and snow accumulation is prevented. Since the peeling point moves to the rear of the wire cross section, the wind pressure load is reduced.
[0020]
In the winding structure of the present invention, when the relational expression of P / D = 9 to 40 is satisfied between the winding pitch P (mm) and the diameter D (mm) of the overhead wire, the wind noise and the amount of snowfall Wind pressure load etc. are reduced most.
In the case of a general overhead ground wire having an outer diameter D of 10.5 mm (cross-sectional area 70 mm ² ), the above relational expression is satisfied when the winding pitch P is 95 to 400 mm.
[0021]
In the winding structure of the present invention, when a plurality of tape-structured optical fiber cables are wound, the degree of protrusion (height / width) of the optical fiber cable can be obtained by winding the side surfaces in close contact with each other in a spiral shape. As a result, the corona resistance of the overhead wire is further improved.
Further, when a plurality of tape-structured wound optical fiber cables are wound in a spiral shape at equal intervals in the circumferential direction, the periodic change of the projected cross-sectional shape becomes extremely small and wind noise is further reduced.
[0022]
By winding in this way, the tape-structured wound optical fiber cable of the present invention can construct a stable optical transmission network over a long period of time.
[0023]
【Example】
The present invention will be specifically described below with reference to the drawings.
Example 1
FIG. 1 is a cross-sectional view showing a first embodiment of a tape structure wound optical fiber cable of the present invention.
In this tape-structured optical fiber cable 11, a soft and easily deformable adhesive layer 31 is provided with a thickness of 1.5 mm on the surface (lower surface) of the tape-shaped optical fiber cable 26 wound around the overhead wire. .
The adhesive layer 31 is formed by laminating a semiconductive adhesive tape in which an appropriate amount of carbon powder is mixed with butyl rubber in multiple layers.
In this optical fiber cable, the adhesive layer is soft and easily deformable, and has an appropriate thickness. Therefore, the adhesive layer almost completely fills the twisted groove of the overhead wire and is extremely firmly fixed to the overhead wire, so that the winding is loosened or displaced. In addition, since the adhesive layer is semiconductive, gap discharge is sufficiently suppressed even when it is wound around an overhead power transmission line (power line).
[0024]
(Example 2)
FIG. 2 is a cross-sectional view showing a second embodiment of the tape-structured wound optical fiber cable of the present invention.
This tape-structured optical fiber cable 12 has a soft and easily deformable adhesive layer 31 on the surface (lower surface) of the tape-shaped optical fiber cable 26 wound around an overhead wire (not shown), and the upper surface and both side surfaces. Each is provided with a protective layer 41 made of silicon rubber. Further, a tension member 32 made of FRP is combined with the adhesive layer 31 (the same adhesive layer used in Example 1).
Since the tension member 32 is combined with the tape-structured wound optical fiber cable 12, the optical fiber cable 12 is prevented from being excessively stretched due to the tension when wound around the overhead wire. Further, the protective layer 41 prevents damage caused by flying objects.
[0025]
(Example 3)
FIG. 3 is a cross-sectional view showing a third embodiment of the tape-structured wound optical fiber cable of the present invention.
The tape-structured wound optical fiber cable 13 is a wide one in which two tape-shaped optical fiber cables 26 and 26 arranged in parallel are collectively covered with a protective layer 41. A soft and easily deformable adhesive layer 31 is provided on the lower surface of the protective layer 41, and the lower surface of the adhesive layer 31 is formed in an arc shape in the width direction so as to make good contact with the overhead wire. For this reason, the tape-like optical fiber cable 26 is not bent when it is wound around an overhead wire, and a great bending stress is applied to the optical fiber 22 so that transmission loss does not increase.
The protective layer 41 and the adhesive layer 31 are made of the same material as in the second embodiment.
In this embodiment, since the adhesive layer 31 is formed in an arc shape so as to make good contact with the overhead wire, the thickness t of the central portion of the adhesive layer 31 is the thinnest. If the thickness t is less than 0.3 mm, sufficient adhesiveness cannot be obtained, and if it exceeds 3 mm, both ends of the adhesive layer 31 become too thick, making it difficult to handle the optical fiber cable 13. Therefore, the thickness t of the central portion of the adhesive layer 31 is preferably about 0.3 to 3 mm.
[0026]
Example 4
FIG. 4 is a cross-sectional view showing a fourth embodiment of the tape-structured wound optical fiber cable of the present invention.
This tape-structured wound optical fiber cable 14 is the same as the optical fiber cable 13 shown in FIG. 3 except that the surface 42 of the protective layer 41 that contacts the adhesive layer 31 is also formed in an arc shape. The applied bending stress is further reduced.
Here, the arcuate curvature of the surface 42 in contact with the adhesive layer 31 of the protective layer 41 is arbitrary, but the thickness t of the central portion of the adhesive layer 31 is preferably about 0.3 to 3 mm for the same reason as described above.
In Examples 3 and 4, the radius of curvature R of the winding surface of the optical fiber cable is preferably about the radius of the overhead wire to be wound.
[0027]
(Example 5)
FIG. 5 is a cross-sectional view showing a fifth embodiment of the tape-structured wound optical fiber cable of the present invention.
This optical fiber cable 15 with a tape structure is formed by laminating two tape-like optical fiber cables 26 and 26 in the optical fiber cable 13 shown in FIG. It can be multi-centered compactly without spreading.
[0028]
(Example 6)
FIG. 6A is a side view showing a first embodiment of a structure for winding an optical fiber cable of the present invention around an overhead wire.
This winding structure is obtained by applying tension to the optical fiber cable 11 shown in FIG. 1 in a spiral manner on an overhead ground wire 54 having a diameter D of 10.5 mm at a winding pitch P (P / D = 38) of 400 mm. Wrapped.
In this winding structure, the adhesive layer 31 substantially fills the twisted groove of the overhead ground wire (see FIG. 6b) and is firmly fixed to the overhead ground wire, so that the winding is loosened and the transmission loss increases. Absent. Moreover, even if the airborne machine gets on, the load (external force) is absorbed by the adhesive layer and the optical fiber is not damaged. Furthermore, since the semiconductive adhesive layer is substantially filled in the twisted groove, gap discharge is prevented and erosion does not occur. Therefore, stable optical transmission is performed for a long time.
Since the optical fiber cable 11 of the present invention shown in FIG. 1 has a tape structure, the winding height is lower than that of the optical fiber cable 21 having a circular cross section (see FIG. 11). In the fiber cable, since the separation point of the airflow moves to the rear of the cross section of the electric wire, the wind pressure load is reduced. Furthermore, it acts as a spiral projection and reduces wind noise.
[0029]
(Example 7)
FIG. 7 is a side view showing a second embodiment of a structure for winding an optical fiber cable of the present invention around an overhead wire.
In this winding structure, the two optical fiber cables 11 and 11 of the present invention shown in FIG. 1 are wound in a spiral shape at a pitch P on an aerial ground wire 54 with the side surfaces in close contact with each other.
The winding structure shown in FIG. 7 is extremely excellent in corona resistance because the degree of protrusion (height / width) of the optical fiber cable is smaller.
The two tape-structured wound optical fiber cables 11 and 11 may be wound at the same time, or may be additionally wound later when the amount of information increases. There may be three windings.
[0030]
(Example 8)
FIG. 8 is a side view showing a third embodiment of the structure for winding an optical fiber cable of the present invention around an overhead wire.
This winding structure is obtained by winding the two optical fiber cables 11 and 11 of the present invention shown in FIG. 1 in parallel to the aerial ground wire 54 and facing each other by 180 degrees at equal intervals in the circumferential direction. It is.
In the winding structure shown in FIG. 8, two optical fiber cables are wound at equal intervals, the periodic change of the projected cross-sectional shape becomes extremely small, and the wind pressure load is remarkably reduced.
[0031]
Example 9
FIG. 9 is a side view showing a fourth embodiment of a structure for winding an optical fiber cable of the present invention around an overhead wire (diameter: 10.5 mm).
In this winding structure, the optical fiber cable 13 of the present invention shown in FIG. 3 is wound around an aerial ground wire 54 in a spiral shape.
In this optical fiber cable 13, since the winding surface of the adhesive layer 31 is formed in an arc shape, the entire winding surface is in good contact with the aerial ground wire 54 and bending stress is applied to the optical fiber. Absent.
[0032]
In the above embodiment, the case where the overhead ground wire is used as the overhead wire has been described. However, the optical fiber cable of the present invention can also be wound around other overhead wires such as an overhead power transmission line (power line) and a distribution line. Similar effects can be obtained.
[0033]
The tape structure wound type optical fiber cable of the present invention uses what is wound around a drum for actual winding work. For this reason, when winding on a drum, for example, in the case of the optical fiber cable shown in FIGS. 2 to 4, separation between the optical fiber cables is performed so that the adhesive layer 31 and the protective layer 41 are not bonded. It is better to take up paper.
[0034]
【The invention's effect】
As described above, the tape-structured wound optical fiber cable of the present invention has a soft and easily deformable adhesive layer of 0.3 to 3 mm on the winding surface (lower surface) of the tape-shaped optical fiber cable to the overhead wire. Therefore, in the optical fiber cable, the adhesive layer is substantially filled in the twisted groove of the overhead wire, and is firmly fixed to the overhead wire, so that the winding is not loosened and transmission loss is unlikely to occur. Since the adhesive layer is soft and easily deformed, it acts as a cushioning material, and even when a suspension machine for maintenance and inspection rides, the load (external force) is absorbed by the adhesive layer, and the optical fiber is not damaged. Further, since the adhesive layer substantially fills the twisted groove of the overhead wire, when the adhesive layer is conductive or semiconductive, gap discharge between the overhead wire and the optical fiber cable is suppressed, and erosion is prevented.
When the optical fiber cable with a tape structure of the present invention is wound around an overhead wire in a spiral shape, convex portions are continuously formed on the overhead wire, and wind noise is reduced and snow is prevented. Further, since the projected cross section changes periodically, turbulent airflow is generated around the overhead wire and the wind pressure load is reduced. The tape structure wound optical fiber cable of the present invention has a tape structure and a low winding height, so that the wind pressure load is small. Therefore, the load on the steel tower is greatly reduced.
The tape structure wound optical fiber cable of the present invention is protected from flying objects by providing protective layers on the upper surface and both side surfaces of the tape-shaped optical fiber cable.
If the winding surface of the adhesive layer on the overhead wire is formed in an arc shape in the width direction so that the entire surface is in contact with the overhead wire, an excessive bending stress is not applied to the wound optical fiber, and the transmission loss of the optical fiber is reduced. Is greatly reduced. Similarly, when the protective layer is formed in an arc shape, the effect is further improved.
When a plurality of tape-structured optical fiber cables are wound with their side surfaces in close contact with each other, the degree of protrusion (height / width) is reduced, so that the corona resistance of the overhead wire is improved.
When a plurality of tape-structured optical fiber cables are wound in a spiral manner at regular intervals in the circumferential direction, the periodic change of the projected cross-sectional shape becomes extremely small and the wind pressure load is significantly reduced.
In the winding structure, if the relational expression of P / D = 9 to 40 (where P is the winding pitch mm of the optical fiber cable and D is the diameter of the overhead wire mm), the wind noise and the amount of snowfall Wind pressure load etc. are best reduced.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a first embodiment of a tape structure wound optical fiber cable of the present invention.
FIG. 2 is a cross-sectional view showing a second embodiment of a tape structure wound optical fiber cable of the present invention.
FIG. 3 is a cross-sectional view showing a third embodiment of the tape structure wound optical fiber cable of the present invention.
FIG. 4 is a cross-sectional view showing a fourth embodiment of the tape structure wound optical fiber cable of the present invention.
FIG. 5 is a cross-sectional view showing a fifth embodiment of a tape structure wound optical fiber cable of the present invention.
FIGS. 6A and 6B are a side view and a cross-sectional view, respectively, showing a first embodiment of a structure in which a tape-structure wound optical fiber cable of the present invention is wound around an overhead wire.
FIG. 7 is a side view showing a second embodiment of a structure in which a tape-structured wound optical fiber cable of the present invention is wound around an overhead wire.
FIG. 8 is a side view showing a third embodiment of a structure in which a tape-structured wound optical fiber cable of the present invention is wound around an overhead wire.
FIG. 9 is a side view showing a fourth embodiment of a structure in which a tape-structure wound optical fiber cable of the present invention is wound around an overhead wire.
FIG. 10 is a cross-sectional view of an optical fiber built-in overhead ground wire.
FIG. 11 is a cross-sectional view of a conventional wound optical fiber cable.
FIG. 12 is a cross-sectional view of a conventional tape-structured wound optical fiber cable.
[Explanation of symbols]
11, 12, 13, 14, 15 Tape structure wound optical fiber cable 21 Optical fiber cable 22 having a circular cross section 22 Optical fiber 23 Silicon resin 24 Optical fiber core wire 25 56 ... Sheath 26 Tape-shaped optical fiber cable 31 Adhesive layer 32 Tension Member 41 Protective layer 42 Surface of protective layer in contact with adhesive layer 51 Optical unit 52 Spacer 53 Recessed portion 54 Overhead ground wire 55 Aluminum tube

Claims (8)

A flexible, easily deformable adhesive layer with a thickness of 0.3 to 3 mm is attached to the surface (bottom surface) of the tape-shaped optical fiber cable in which a plurality of optical fiber cores are arranged on the same plane and the sheath is collectively covered. A tape-structured wound optical fiber cable characterized by being provided in a cable. 2. The tape-structured wound optical fiber cable according to claim 1, wherein protective layers are provided on the upper surface and both side surfaces of the tape-shaped optical fiber cable. 3. The tape-structure-wound light according to claim 1, wherein a surface of the adhesive layer that is wound around the overhead wire is formed in an arc shape in the width direction so that the entire surface is in contact with the overhead wire. Fiber cable. The tape-structure wound optical fiber cable according to any one of claims 1, 2, and 3, wherein the adhesive layer is conductive or semiconductive. An overhead wire around which the tape-structured wound optical fiber cable according to any one of claims 1, 2, 3, and 4 is wound , wherein the tape-structured wound optical fiber cable has an adhesive layer formed on the aerial wire. overhead line you characterized by being wound in substantially fills the Yomizo line. 6. The overhead wire according to claim 5, wherein a plurality of the tape-structured wound optical fiber cables are wound in a spiral shape with their side surfaces in close contact with each other. 6. The overhead wire according to claim 5, wherein a plurality of the tape-structured wound optical fiber cables are wound spirally at equal intervals in the circumferential direction. The above-mentioned tape-structured optical fiber cable has a relational expression of P / D = 9-40 on the overhead wire (where P is the winding pitch mm of the tape-structured optical fiber cable and D is the diameter of the overhead wire mm) The overhead wire according to claim 5, wherein the overhead wire is wound so as to satisfy the above requirements.

Images