JPH07336854A - Optical fiber composite overhead ground jumper device - Google Patents

Abstract

(57) [Summary] [Purpose] To prevent severe stress from occurring in the jumper part of the optical fiber composite overhead ground wire. [Structure] Optical fiber composite overhead ground wire 2 retaining metal fitting 2
Hold it on the tower 1 via 1A and 21B. Both detent metal fittings 2 of the optical fiber composite overhead ground wire 2 and the vicinity of both ends of the metal filament 24 disposed between both detaining metal fittings 21A and 21B.
Retaining bracket 21 of jumper portion 2a between 1A and 21B
The positions near A and 21B are electrically connected to each other via the clamp fittings 25. The intermediate portion of the metal filament 24 is fixed to the steel tower 1 in an electrically connected state by a fixing member 26. Jumper part 2 of optical fiber composite overhead ground wire 2
Since a is not directly fixed to the steel tower 1 which is a completely rigid body but is only connected to the metal filament 24 having bending elastic force, the optical fiber composite overhead ground wire 2 in the span portion of the steel tower is used. Even if galloping, three-jump, or other vibration occurs, no large stress is generated in the jumper portion 2a.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a jumper device for an optical fiber composite overhead ground wire.

[0002]

2. Description of the Related Art Conventionally, a jumper device for an optical fiber composite overhead ground wire having a structure shown in FIG. 9 is known. In the figure, reference numeral 1 is a steel tower, and reference numeral 2 is an optical fiber composite overhead ground wire. In this conventional structure, two points on both sides of the optical fiber composite overhead ground wire 2 which sandwich the steel tower 1 are retained to the steel tower 1 via the retaining metal fittings 3A and 3B and the connecting metal fitting 4, respectively. The central portion of the jumper portion (that is, the portion between the left and right retaining metal fittings 3A, 3B) 2a is fixed to the steel tower 1 by the jumper clamp 5 to form a jumper device indicated by reference numeral 6 as a whole. In addition, the connecting metal fittings 4 between the respective holding metal fittings 3A, 3B for clamping the optical fiber composite overhead ground wire 2 and the steel tower 1
Has a plurality of pin connecting portions 4a, 4b, 4c, 4d, and is insufficient for the purpose of electrical connection. Therefore, the optical fiber composite overhead ground wire 2 is connected to the tower 1 by the jumper clamp 5 as described above. It is fixed to secure the electrical connection with the tower 1. The structure of the optical fiber composite overhead ground wire 1 is similar to that of the present invention, and as shown in the cross section of FIG.
A plurality of aluminum-covered steel wires 11 each having an aluminum layer 10 on the outer circumference of a steel core 9 are twisted together as a metal element wire around the core.

[0003]

[Problems to be Solved by the Invention] For electric wires between steel towers,
Various vibrations such as galloping, three jumps, etc. occur. In the conventional jumper device 6 for an optical fiber composite overhead ground wire, since the jumper portion 2a of the optical fiber composite overhead ground wire 2 is directly fixed to the steel tower 1 which is a completely rigid body by the jumper clamp 5, When various kinds of vibrations occur in the optical fiber composite overhead ground wire 2 in the steel tower span, the jumper clamp 5 of the jumper part 2a
At this time, a large stress is generated at the portion (the portion indicated by the arrow (a)). When this stress generation is repeated, fatigue fracture may occur in the aluminum pipe 8 inside the optical fiber composite overhead ground wire 2. When the aluminum pipe 8 is fatigue fractured, the airtightness is impaired and the transmission loss characteristic of the optical fiber cable 7 is deteriorated.
In addition, the wires of the optical fiber cable 7 may be broken.

The present invention has been made in order to solve the above-mentioned conventional problems, and an optical fiber composite overhead ground wire which does not cause severe stress in a jumper portion of the optical fiber composite overhead ground wire retained in a steel tower. An object of the present invention is to provide a jumper device.

[0005]

A jumper device for an optical fiber composite overhead ground wire according to the present invention which solves the above-mentioned problems is provided with two isolated points of the optical fiber composite overhead ground wire in a steel tower located between the two points. The clamps are clamped between the both ends of the metal filaments arranged between the two retaining metal fittings and the positions near the respective retaining metal fittings in the jumper section between the two optical fiber composite overhead ground wire retaining metal fittings. It is characterized in that it is connected in an electrically connected state via the, and the middle portion of the metal filament is fixed in an electrically connected state to the steel tower by a fixing metal fitting.

[0006]

In the above structure, the jumper portion of the optical fiber composite ground wire is not directly fixed to the steel tower, which is a completely rigid body, but is connected to the metal filament having bending elasticity through the clamp metal fittings. However, even if galloping, three-jump, or other vibrations occur in the optical fiber composite overhead ground wire in the span of the steel tower, no large stress is generated in the jumper. Further, the jumper portion of the optical fiber composite overhead ground wire is surely electrically connected to the steel tower through the metal filament.

[0007]

Embodiments of the present invention will be described below with reference to FIGS. FIG. 1 is a front view of a jumper device 20 for an optical fiber composite overhead ground wire according to the present invention. In the same figure, the optical fiber composite overhead ground wire 2 is connected to the steel tower 1 at two points on the left and right sides of the steel tower 1 via retaining metal fittings 21A and 21B and a connecting metal fitting 22, respectively. In this embodiment, each retaining metal member 21 of the optical fiber composite overhead ground wire 2 is
An armor rod 23, which is a spiral protection member made of metal, is wound around the portion clamped by A and 21B and in the vicinity of the front and rear thereof, as shown in a partially enlarged view in FIG.

Then, a metal filament 24 is added to the jumper portion 2a of the optical fiber composite overhead ground wire 2. As the metal filament 24, it is preferable to use a stranded aluminum wire or the like in consideration of formability. The vicinity of both ends of the metal filament 24 and the vicinity of the left and right retaining metal fittings 21A, 21B of the jumper portion 2a are integrally clamped by a clamp metal fitting 25 as shown in an enlarged view in FIG. Are connected to each other. The metal filament 24 has a curved shape in which the central portion in the longitudinal direction is a valley and the left and right sides thereof are ridges, and the central portion is fixed to the tower 1 in an electrically connected state by a fixing metal fitting 26. There is. Reference numeral 27 is a retaining metal fitting 2 in the damper attached to the optical fiber composite overhead ground wire 2.
At the position closest to 1A (called the first damper)
Indicates. As shown in FIG. 2, the structure of the optical fiber composite overhead ground wire 1 is, for example, as a metal element wire around an aluminum pipe 8 containing an optical fiber cable 7, for example, on the outer circumference of a steel core 9. This is a structure in which a plurality of aluminum-covered steel wires 11 having an aluminum layer 10 are twisted together.

The jumper portion 2a of the optical fiber composite overhead ground wire 2 shown in the embodiment of FIG. 1 simply extends in the left and right in a gentle mountain shape, but in an actual jumper device, the schematic plan view of FIG. As shown in the schematic front view of FIG. 8, it is often the case that the jumper portion 2a of the optical fiber composite overhead ground wire 2 is routed in a loop on the tower 1. In this case, a plurality of positions of the jumper portion 2a are clamped by the cleat 28 and fixed to the tower 1.

The winding range of the armor rod 23 is appropriately set according to various conditions, and an example thereof will be described. Armor rod 23 retaining metal 21A (21
B) Extension length S ₁ closer to the span side: When the distance from the retaining metal fitting 21A to the mounting position of the first damper 27 is Ld, the position of the tip of the armor rod 23 is 0.5Ld from the tip of the retaining metal fitting 21A. range ～1.5Ld (i.e. 0,5Ld <S ₁ <1.5Ld) attached so as to. This setting is set in consideration of minimizing the strain generated in the optical fiber composite overhead ground wire 2 during vibration and the workability of winding the armor rod 23. In addition, the first damper 2 of the optical fiber composite overhead ground wire 2
It is also taken into consideration that no serious problematic stress is generated in the portion closer to the span than 7. Extending length S _{2 of the} armor rod 23 from the retaining metal fittings 21A (21B) to the steel tower 1 side: (a) In the case of a through steel tower The length of the optical fiber composite overhead ground wire 2 between the left retaining metal fittings 21A and 21B (jumper part) 2a of length) in the case of the Lj, the anchor bracket 21A position of the tip of the Amaroddo 23, the range of 100mm~0.5Lj from the outlet of the 21B (i.e., 100 mm <such that S ₂ <0.5Lj) To do. (B) In the case of a pull-down steel tower In FIG. 7, from the respective holding metal fittings 21A, 21B,
When the distance to the cleat 28 is Lc, the position of the tip of the armor rod 23 is in the range of 100 mm to Lc from the exit of the retaining metal fittings 21A, 21B (that is, 100 m).
m <S ₄ <Lc). The above-mentioned setting minimizes the strain generated in the jumper portion 2a of the optical fiber composite overhead ground wire 2 during vibration, and the clamp metal fitting 2
5 is set in consideration of the workability of mounting and the formability of the metal filament 24. Mounting position of the clamp 25: Clamp 25
Is 100 mm from the exit of the retaining metal fittings 21A, 21B
Range ～0.5Lj (i.e., when the distance to the clamp bracket 25 and the S ₃ from detention fitting 21A (21B) as in FIG. _{1, 100mm <S 3 <0.5Lj} ) attached to. In order to reduce the stress generated in the optical fiber composite overhead ground wire 2 (jumper portion 2a), the armor rod 23 is wound around the clamp metal fitting 25 of the optical fiber composite overhead ground wire 2 (jumper portion 2a). Since it is effective, it is better to wind the armor rod 23 around the clamp metal fitting 25 mounting portion of the optical fiber composite overhead ground wire 2 (jumper portion 2a) as in the illustrated example. However, the optical fiber composite overhead ground wire 2 (jumper part 2a) is directly connected to the clamp metal fitting 2
It may be clamped at 5. By the above settings of ~,
The optical fiber composite overhead ground wire 2 (jumper portion 2a) is appropriately reinforced by the armor rod 23, and the workability is also improved.

FIG. 5 shows another embodiment of the manner of routing the metal filament 24. The metal filament 24 of this embodiment
1 has a curved shape in which the central portion is a valley and the left and right sides are ridges as in FIG. 1, and the curved shape is formed below the jumper portion 2a of the optical fiber composite overhead ground wire 2. Is. The other points are the same as in the embodiment of FIG.

FIG. 6 shows still another embodiment of the drawn state of the metal filament. The metal filament 2 of this embodiment
4 is provided below the jumper portion 2a of the optical fiber composite overhead ground wire 2 as in FIG. 5, but the central portion is slightly extended to the left and right, and the central portion is a back portion. It is fixed to the steel tower 1 through a high fixing metal fitting 26. The other points are the same as in the embodiment of FIG.

The structure of the retaining metal fittings 21A, 21B is not limited to the illustrated example. In short, it suffices if the intermediate portion of the optical fiber composite overhead ground wire 2 can be clamped and retained on the tower 1 instead of the end portion. Further, the clamp fitting 25 that connects the jumper portion 2a of the optical fiber composite overhead ground wire 2 and the metal filament 24 is not limited to the structure of the embodiment. In short, it suffices if the optical fiber composite overhead ground wire 2 and the metal filament 24 can be connected in an electrically connected state.

[0014]

According to the present invention, the jumper portion 2a of the optical fiber composite overhead ground wire is not directly fixed to the steel tower which is a completely rigid body, but is clamped to the metal filament 24 having a bending elastic force. Since they are connected via the metal fittings 25,
Even if galloping, three-jump, or other vibrations occur, the jumper portion 2a of the optical fiber composite overhead ground wire 2 will no longer have the stress as seen in the conventional structure. Therefore, the optical fiber composite overhead ground wire 2
It is possible to eliminate the risk of damage to the aluminum pipe 8 inside, and deterioration of the transmission loss characteristics of the optical fiber cable 7 and disconnection of the strands.

According to the second aspect, since the armor rod 23 is wound around the portion of the optical fiber composite overhead ground wire 2 clamped by the retaining metal fittings 21A and 21B and the outer periphery in the vicinity of the front and rear thereof, the bending rigidity is sharp. Since the change is prevented, that is, the bending rigidity gradually changes from the holding metal fittings 21A and 21B to the winding portion of the armor rod 23 and further to the portion of the optical fiber composite overhead ground wire 2 (jumper portion 2a). , Optical fiber composite overhead ground wire 2 (jumper portion 2a) retaining metal fittings 21A, 21B
No large stress is generated in the portion at the time of the above, the boundary portion between the armor rod 23 and the overhead ground wire 2 (jumper portion 2a), etc., and it is possible to prevent the mechanical damage or the like of each portion.

According to the third aspect of the present invention, the length of the jumper portion 2a of the optical fiber composite overhead ground wire is set so that both the holding metal fittings 21A, 2A.
Since it is sufficiently longer than the straight line distance between 1B and the center part of the jumper part 2a is not fixed by the fixing metal fittings as in the conventional case, the jumper part is adjusted when the sag between the steel towers is adjusted. Can be prevented from becoming shorter than the required length of the jumper section. Therefore, a large stress does not occur in the jumper portion 2a due to the sag adjustment work, and it is possible to prevent mechanical damage or the like of each portion.

[Brief description of drawings]

FIG. 1 is a front view showing a jumper device for an optical fiber composite overhead ground wire according to an embodiment of the present invention.

FIG. 2 is an enlarged cross-sectional view of the optical fiber composite overhead ground wire in FIG.

FIG. 3 is an enlarged side sectional view taken along line AA of FIG.

FIG. 4 is an enlarged front view of a B part in FIG.

FIG. 5 is a front view showing another embodiment of the jumper device for an optical fiber composite overhead ground wire according to the present invention.

FIG. 6 is a front view showing still another embodiment of the jumper device for an optical fiber composite overhead ground wire according to the present invention.

FIG. 7 is a plan view schematically showing a jumper device for an optical fiber composite overhead ground wire according to another embodiment of a manner of routing a jumper portion of the optical fiber composite overhead ground wire according to the present invention. .

8 is a schematic front view of the jumper device for the optical fiber composite overhead ground wire shown in FIG.

FIG. 9 is a front view showing a conventional jumper device for an optical fiber composite overhead ground wire.

[Explanation of symbols]

 1 Steel Tower 2 Optical Fiber Composite Overhead Ground Wire 2a Jumper Part 7 Optical Fiber Cable 8 Aluminum Pipe 11 Aluminum Covered Steel Wire 20 Optical Fiber Composite Overhead Ground Wire Jumper Device 21A, 21B Retaining Fitting 22 Connecting Fitting 23 Armor Rod 24 Metal Wire Strip 25 Clamp metal fitting 26 Fixing metal fitting 27 Damper

Claims (3)

[Claims] 1. An optical fiber composite aerial ground wire (2) is separated from two points separated to a steel tower (1) located between the two points via retaining metal fittings (21A) and (21B), respectively. Metal fittings (24) disposed between the metal fittings (21A) and (21B) and both ends of the metal fiber strip (24) and the optical fiber composite overhead ground wire (2) are retained by the metal fittings (21A) and (21B).
Each holding metal fitting (21) in the jumper part (2a) between
A) and (21B) and the vicinity thereof are electrically connected to each other via a clamp metal fitting (25), and the middle portion of the metal filament (24) is fixed to a steel tower (1) by a fixing metal fitting (26). An optical fiber composite overhead ground wire jumper device characterized by being fixed in an electrically connected state. 2. An armor rod (23) is provided on a portion of the optical fiber composite overhead ground wire (2) that is clamped by the retaining metal fittings (21A), (21B) and on the outer periphery in the vicinity of the front and rear thereof.
The optical fiber composite overhead ground wire jumper device according to claim 1, wherein the jumper device is wound around. 3. The optical fiber composite aerial land according to claim 1, wherein the jumper portion (2a) has a length that is sufficiently longer than a straight line distance between the two retaining metal fittings (21A), (21B). Wire jumper device.