JPH1139950A - Vibration suppression type overhead electric wire and method of manufacturing the electric wire - Google Patents

Abstract

(57) [Summary] A vibration-suppressing electric wire and a wire capable of suppressing a behavior of freely moving the electric wire in a vertical direction by generating a force for pushing the electric wire downward when wind blows, and the electric wire. And a method for producing the same. A cross-sectional shape is made asymmetrical up and down to increase the radius of curvature of the upper surface and to decrease the radius of curvature of the lower surface. The vertically asymmetric surface shape may be formed in the outermost layer of the stranded wire or in the insulating coating of the insulated wire. When the electric wire is a bare electric wire, it is preferable to crush and form a stranded wire which has been manufactured in advance in a symmetrical shape in cross-section such that the upper surface has a larger radius of curvature and the lower surface has a smaller radius of curvature in the cross-sectional shape. On the other hand, when the wire is an insulated wire, when extruding the insulating coating on the conductor, it is preferable to extrude the insulating coating such that the upper surface has a larger radius of curvature and the lower surface has a smaller radius of curvature.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the technology of an overhead electric wire, and more particularly to a vibration-suppressing electric wire capable of suppressing vibration in an overhead electric wire which tends to generate vibration such as wind vibration or galloping due to wind. And a method for manufacturing the electric wire. The term "overhead electric wire" is used in a concept that includes a bare electric wire as seen in an overhead transmission line and an insulated electric wire as seen in an overhead distribution line.

[0002]

2. Description of the Related Art This type of overhead electric wire is generally finished so that its cross-sectional shape is circular. Particularly, in the case of an overhead power transmission line (an overhead ground wire), several aluminum wires, copper wires, steel wires and the like are used. Were twisted so that the cross-sectional shape of the stranded wire was circular. 3 and 4 show examples of the structure of a typical overhead electric wire.

The overhead electric wire shown in FIG. 3 is an example in which a large number of round conductor strands 2 having a circular cross section are stranded on a central stranded wire 1 so as to be finished in a circular shape. On the other hand, the overhead electric wire in FIG. 4 is an example in which a large number of irregularly shaped conductor strands 3 having a rectangular cross section are stranded on a central stranded wire 1 'so as to be finished in a circular shape.

[0004]

According to FIGS. 3 and 4, there are the following problems. That is, there is a tendency for the electric wires to oscillate, such as wind vibration and galloping due to the wind, and as shown in FIGS.
Since the cross-sectional shape of the electric wire is circular and symmetrical in the vertical and horizontal directions, the cross-sectional shape of the electric wire is symmetric with respect to the flow of wind,
Therefore, the vibration is free in the vertical and horizontal directions, and the electric wire is easily vibrated in the vertical and horizontal directions.

[0005] As a result, the wires constituting the electric wire may cause vibration fatigue or trip between power line phases.

Therefore, the problems to be solved by the present invention (objects)
Is to provide a vibration suppression type electric wire and a method for manufacturing the electric wire, which can generate a force to push down the electric wire when wind blows, and can suppress a behavior of freely moving the electric wire in a vertical direction. It is in.

[0007]

The vibration suppressing type electric wire provided by the present invention is vertically asymmetrical in cross-sectional shape.
The radius of curvature of the upper surface is large and the radius of curvature of the lower surface is small.

With the above configuration, when a cross wind blows against the electric wire, the flow of air is slow on the upper surface of the electric wire having a larger radius of curvature, and the flow of air is faster on the lower surface of the electric wire having a smaller radius of curvature. As a result of such a difference in air flow between the top and bottom of the wire, the wire is subjected to a force that pushes the wire downward, where the air flow is fast, and thus the vertical deflection of the wire can be suppressed. It becomes possible.

When the electric wire of the present invention is a bare electric wire, it is preferable that the upper and lower asymmetric surface shape is formed in the outermost layer of the stranded wire.

When the electric wire of the present invention is an insulated electric wire, the asymmetric cross-sectional shape is preferably formed in an insulating coating of the insulated electric wire.

The method for manufacturing a vibration-suppressing electric wire provided by the present invention is based on the premise that the electric wire is a bare electric wire.
Twisted wires manufactured in advance in a symmetrical shape in cross section
It is a method of crushing and molding such that the radius of curvature of the upper surface is large and the radius of curvature of the lower surface is small in the sectional shape.

As described above, the method of crushing and forming a stranded wire manufactured symmetrically in cross-sectional shape makes it easy to manufacture an electric wire asymmetrical in cross-sectional shape. Incidentally, it is difficult to twist the wire so as to have a shape in which the radius of curvature of the upper and lower surfaces is maintained in the line direction of the electric wire. The above-mentioned crushing molding can be achieved by a simple means of molding with a compression force by a compression roll or the like.

Another method of manufacturing a vibration-suppressing electric wire provided by the present invention is a method for extruding an insulating coating on a conductor when the electric wire is an insulated electric wire. Extrusion molding is performed so that the radius of curvature is large and the radius of curvature of the lower surface is small.

[0014]

1 and 2 show an embodiment of the present invention. FIG. 1 shows a stranded wire before crushing and molding, and FIG. 2 shows a stranded wire after crushing and molding.

The vibration-suppression type electric wire of this embodiment is composed of a round conductor element 20 having a circular cross section made of an aluminum wire and having a circular cross section made of an aluminum wire, as shown in FIG. A large number of strands are twisted to produce a stranded wire 30 in which the outermost layer of the round conductor strand 20 is finished in a circular symmetric shape.

Then, the symmetrical stranded wire 30 manufactured as described above is compressed and crushed with a compression roll from above and below the stranded wire as shown in FIG. 2, that is, the symmetrical stranded wire 30. As a result, the upper surface 40 has a large radius of curvature,
Is formed into a vertically asymmetrical (symmetrical) stranded wire 30 'having a small radius of curvature, which is used as a vibration-suppressing electric wire.

As described above, a steel wire is used for the center line 10,
By using an aluminum wire for the outer stranded wire, it is possible to easily perform the squeeze molding to the outermost layer of the stranded wire and to increase the processing accuracy. The material of each of the strands has been described as a typical example of a preferable one, and other materials such as hard copper and copper can also be used.

The above embodiment is based on the premise that bare wires are found in power lines for overhead power transmission lines and overhead ground wires. However, the present invention is not limited to this and can also be applied to insulated wires for distribution lines. In this case, this can be realized by extruding the shape of the insulating coating of the insulated wire in a vertically asymmetric (laterally symmetric) shape having different curvature radii as described above.

[0019]

According to the present invention as described above, a force that pushes down the electric wire when the wind blows can be generated, and the behavior of freely moving the electric wire in the vertical direction can be suppressed. It is possible to achieve an intended object (object) of providing a vibration-suppressing electric wire and a method of manufacturing the electric wire, thereby preventing a jump that may be a problem in an overhead electric wire, thereby suppressing a run-out. It has the effect of being able to do so.

[Brief description of the drawings]

FIG. 1 is a cross-sectional explanatory view showing a structure of a symmetrical stranded wire having a circular cross section before being crushed and molded according to an embodiment of the present invention.

FIG. 2 is a cross-sectional explanatory view showing a structure of a vibration-suppression type electric wire finished to be asymmetrical in cross section by crushing molding according to the embodiment of the present invention.

FIG. 3 is a cross-sectional explanatory view showing a stranded wire finished in a circular cross section by a round wire in a conventional example.

FIG. 4 is a cross-sectional explanatory view showing a stranded wire finished to have a circular cross section by a composite of a round wire and a rectangular shaped wire as a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Center line 20 Conductor wire 20 'Conductor wire after crushed molding 30 Symmetrical stranded stranded wire with circular cross section 30' Asymmetric stranded stranded wire with irregular cross section; Vibration suppression type electric wire 40 Upper surface with large radius of curvature 50 Lower surface with small radius of curvature

Claims (5)

[Claims] 1. A vibration-suppressing overhead electric wire which is vertically asymmetrical in cross-sectional shape so that the upper surface has a larger radius of curvature and the lower surface has a smaller radius of curvature. 2. The vibration-suppression type overhead electric wire according to claim 1, wherein said vertically asymmetric surface shape is formed in an outermost layer of a stranded wire. 3. The vibration-suppression type overhead electric wire according to claim 1, wherein said asymmetric cross-sectional shape is formed in an insulating coating of an insulated electric wire. 4. A stranded wire which is manufactured in advance in a symmetrical shape in cross-sectional shape is crushed and formed such that the upper surface has a larger radius of curvature and the lower surface has a smaller radius of curvature in the cross-sectional shape.
Manufacturing method of vibration suppression type overhead electric wire. 5. A vibration-suppression type overhead electric wire, wherein when extruding an insulating coating on a conductor, the insulating coating is extruded so as to have a large radius of curvature on the upper surface and a small radius of curvature on the lower surface in the cross-sectional shape of the insulating coating. Production method.