JPH0365096B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an improved overhead line vibration isolator, and more particularly to a bait damper.

[Prior Art] A Bate damper, which is a distributed constant damper, has a conventional configuration as shown in Fig. 1.
Add wires 2 consisting of a long one-piece twisted wire, and sequentially l ₁ ,
L ₂ …ln wire 1 with loops of different lengths
It will be fixed to . By fixing the wire 1 in this way, vibrations of various frequencies occur in the wire 1, while low frequency vibrations occur on the long loop _l1 side, and low frequency vibrations occur on the short loop ln (n = 4 in the case of Fig. 1) side. The purpose is to absorb vibrations at high frequencies and exhibit vibration prevention effects over a relatively wide range of frequencies.

However, in the case of such a configuration, in a line with a long span length or a line made of thick electric wires, the input energy of the wind that causes vibration is large, and the entire extension wire 2 becomes longer, resulting in l ₁ + l ₂₊
…ln≧10m. Naturally, if it is so long, the workability will be significantly worse.

Furthermore, such dampers are prefabricated with a structure commensurate with the span length based on in-factory tests, and if the damper is long, the task of installing it becomes even more difficult. . In addition, since l ₁ , l ₂ ,...ln consist of one continuous extension wire, they cannot be applied to vibration isolation for other spans, and must always be manufactured as a single item. There is an inconvenience that there is no such thing.

Therefore, the configuration shown in FIGS. 2 and 3 was studied as a configuration to eliminate this drawback. That is, as shown, the respective loop lengths l ₁ and l ₂
One end of the filaments 2a, 2b, 2c, 2d..., which have been divided into lengths corresponding to ln, is collectively fixed to the electric wire 1, and the other ends of the filaments 2a, 2b, 2
By fixing them at positions corresponding to the lengths of c, 2d, . . . , the shorter filaments are arranged successively inside the longer filaments. In this case, the lengths, materials, configurations, and sizes of 2a, 2b, 2c, etc. are determined so that each has absorption ability in its preferred frequency band.

In this way, the filaments 2a, 2b, 2c...
can be prepared in general as having a unique vibration-proofing ability, and these filaments 2a, 2
From among b, 2c, etc., it is possible to select and employ a filament having the necessary length and frequency band characteristics depending on the span. By doing this, we were able to overcome the fatal flaw of the conventional distributed constant type damper as shown in Fig. 1, which is the one-piece manufacturing process, and make it possible to create an extremely versatile damper.

Furthermore, in a bait damper having such a configuration, the loop is never longer than the longest loop _l1 .
That is, the installation can be made extremely compact, and the ease of construction and workability can be greatly improved. In other words, in terms of installation workability, the damper can be handled on the same level as a torsional damper or a centralized damper such as a stock bridge.

[Problems to be Solved by the Invention] However, such a configuration does not eliminate all problems. That is, Fig. 2,
In the case of the configuration shown in Fig. 3, in order to achieve an even vibration prevention effect against a wide range of vibration modes of the electric wire 1, it is necessary to adjust the length when preparing the wires 2a, 2b, 2c, 2d... In addition to carefully considering the position of the filament, the position of fixing the filament must also be carefully considered.
The problem is that certain limitations are imposed on versatility. This is because, in order to achieve an efficient vibration prevention effect, it is necessary to fix the filament at the nodes and antinode positions against the various vibration modes of the electric wire, but one end of the filament is fixed all at once. Because
This is because if even one fixing position is determined, all other fixing positions are automatically determined, and any change in the fixing position becomes ineffective except by changing the loop length of the filament. In this case,
Application to electric wires having various span lengths, tensions, etc. is self-limited.

Furthermore, as a result of various tests conducted by the applicant,
The following problems were also revealed. That is, since one end of the filament is fixed to the overhead wire all at once, the vibrational strain of the filament is concentrated at the fixed location, and the mechanical strength of this portion of the overhead wire deteriorates early.

The present invention has been made based on this viewpoint, and its purpose is to achieve a broader range of construction without impairing the effects of simplifying and facilitating workability and workability shown in FIGS. 2 and 3. It is an object of the present invention to provide a vibration isolating device for an overhead line that is versatile and capable of preventing deterioration of the mechanical strength of the overhead line due to concentration of vibration distortion.

[Means for Solving the Problems] That is, the gist of the present invention is to attach a plurality of long and short stranded wires prepared in advance to an overhead line so that the shorter strands are sequentially placed inside the longer strands. In a vibration isolating device that absorbs vibrations into the plurality of stranded wires,
The present invention provides a vibration isolating device for an overhead line, in which each stranded wire is independently fixed to the overhead line, and fixed ends are distributed at substantially symmetrical positions on the left and right sides.

In addition, when preparing the stranded wire in advance, in addition to the length,
The number of twists and thickness are determined.

[Example] Hereinafter, an example of the present invention will be described with reference to FIG. The difference from Figures 2 and 3 is that the filament 2
The one end of a, 2b, 2c, 2d, . That is, the filaments 2a, 2b, 2 prepared in advance
Adjust the fixed positions of both ends to the left and right while keeping the loop lengths l ₁ , l ₂ , l ₃ , and l ₄ of c and 2d, so that the fixed ends are in approximately symmetrical positions as shown in the figure. It is distributed over the air and attached to the overhead line 1. Here, the reason why the fixed ends are distributed almost symmetrically is to avoid the vibration strain generated at the fixed ends from concentrating on one point and to disperse it in the longitudinal direction. This can prevent deterioration of the mechanical strength of overhead wires, which was a problem in 2011. Even in that case, the length of the loop _l1 will not be longer than the longest loop, so its compactness will not be impaired. Therefore, it can be applied to various types of electric wires with good versatility.

[Effects of the Invention] As explained above, according to the present invention, although it is compact, the fixing position of the filament is easy to adjust and has excellent versatility. It is possible to provide a vibration isolating device that can prevent wire deterioration.

[Brief explanation of drawings]

1 to 3 are explanatory diagrams showing a conventional bait damper, and FIG. 4 is an explanatory diagram showing an embodiment according to the present invention. 1: Electric wire, 2: Extension wire, 2a, 2b, 2c, 2
d: striae.

Claims (1)

[Claims] 1. A vibration isolator that attaches multiple long and short stranded wires prepared in advance to an overhead line so that the shorter strands are sequentially inside the longer stranded wires, and absorbs vibrations into the multiple stranded wires. A vibration isolating device for an overhead line, in which each stranded wire is independently fixed to the overhead line, and the fixed ends are distributed at substantially symmetrical positions on the left and right sides.