JPH06101261B2 - Noise prevention insulator - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a noise prevention insulator capable of preventing the generation of sound due to wind.

[0002]

2. Description of the Related Art Generally, a porcelain insulator constituting a suspended porcelain is provided with a cap portion and a plurality of pleats formed in an annular and concentric manner on the inner surface of the cap portion. And a plurality of suspension insulators are connected in series to form a suspension insulator string, and the suspension insulator string is suspended from and supported by a support arm of a steel tower, and a power transmission line is supported at its lower end.

[0003]

However, when the suspension insulator series is exposed to a strong wind, and the wind hits the folds of each suspension insulator, air vibrations occur in the space between the folds. There was a case where a very loud noise was generated. An object of the present invention is to provide a noise prevention insulator capable of preventing the generation of sound due to wind.

[0004]

In order to achieve the above object, according to the present invention, a cap portion is provided on an insulator body, and a plurality of pleats are formed on the inner side surface of the cap portion in an annular shape and concentrically. In the insulator provided, between the first fold portion provided at the outermost end of the cap portion and the second fold portion adjacent to the first fold portion, the tip edge portion of the first fold portion and the first fold portion are provided. 2 The line that passes through the leading edge of the pleats should be at least 35 with respect to the horizontal line.
The relationship is set so that the angle is more than a degree.

[0005]

Therefore, according to the present invention, even if the insulator is exposed to a strong wind, the generation of sound in the space between the folds is prevented.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. As shown in FIG. 1, an insulator main body 1 constituting a suspension insulator includes a cap portion 2, a plurality of pleated portions 3 formed on the inner surface of the cap portion 2 in an annular and concentric manner, and further the cap portion. It is integrally formed with a cylindrical head portion 4 having a lid formed on the upper center of 2.

A cap metal fitting 6 is capped and fixed by cement 5 on the outer circumference of the head 4. An engagement recess 6a is formed on the upper surface of the cap fitting 6 so that the pin fitting 7 of another suspension insulator connected directly above can be engaged. The upper part of the pin fitting 7 is inserted into a fitting recess 8 formed inside the head 4, and is fixed by cement 9.
Further, the lower end of the pin metal fitting 7 is engaged with the fitting recess 6a of the cap metal fitting 6 of another suspension insulator connected directly below. In this way, the suspension insulator string 10 is formed by connecting a plurality of suspension insulators in series.

Here, the fold portion 3 formed on the cap portion 2
Among them, the fold portion 3 formed at the outermost end of the cap portion 2 is referred to as a first fold portion 3a, and the fold portion 3 adjacent to the first fold portion 3a is referred to as a second fold portion 3b. The first folds 3a are formed so as to be the longest, that is, extend to the bottom, as compared with the other folds 3, and the second folds 3b are formed shorter than the first folds 3a. That is, as shown in FIG. 1, between the first fold portion 3a and the second fold portion 3b, a line L passing through the lower end edge of the first fold portion 3a and the lower end edge of the second fold portion 3b. Is set such that the angle θ with respect to the horizontal line S is at least 35 degrees or more. In this embodiment, the angle θ is set to 40 degrees.

The inventor of the present application has found that a line L passing through the lower end edge of the first fold portion 3a and the lower end edge of the second fold portion 3b forms an angle of at least 35 degrees with respect to the horizontal line S. It was confirmed by the following test that the sound generation due to the wind can be prevented by setting the above condition. Here, the test method will be described. As shown in FIG. 2, an air outlet 12 of 80 cm square is formed on the wall surface of the wind tunnel laboratory 11 at a height of 1 m above the ground. On the ceiling of the wind tunnel laboratory 11, a suspension insulator string 10 formed by connecting a plurality of suspension insulators is suspended and supported at a position 75 cm away from the air outlet 12. In order to measure the sound pressure level of the noise generated from the suspension insulator series 10 by wind, the sound collecting microphone 1 is placed at a height of 1.3 m above the ground and at a position 50 cm away from the suspension insulator series 10.
3 are installed. The air velocity from the air outlet 12 is 30m /
The wind of s is sent to the suspension insulator string 10 in the vertical direction, that is, parallel to the horizontal line S.

A plurality of insulator bodies are prepared as test samples. That is, as shown in FIG. 3, the insulator body A is
The second fold portion 3b is formed longer than the first fold portion 3a, and the line L passing through the lower end edge of the first fold portion 3a and the lower end edge of the second fold portion 3b is an insulator with respect to the horizontal line S. It forms an angle of 17 degrees in which the center side is lowered. As shown in FIG.
In the insulator body B, the first folds 3a are 3 more than the second folds 3b.
mm longer, that is, the lower edge of the first fold 3a and the second fold
The line L passing through the lower end edge of the fold portion 3b has almost no angle to the horizontal line S.

As shown in FIG. 5, the insulator body C includes a cap portion 2
The outer edge portion of is further outwardly projected from the first fold portion 3a. And the first folds 3a are the second folds 3
It is formed to be longer than b, and the lower end edge of the first fold 3a and the second fold
A line L passing through the lower end edge of the fold portion 3b forms an angle of 40 degrees with respect to the horizontal line S so that the insulator center side rises.

As shown in FIG. 6, in the insulator body D, as compared with the insulator body C, the first fold portion 3a is bent outward at an intermediate portion thereof. And the first fold 3
Line L passing through the lower edge of a and the lower edge of the second fold 3b
However, as with the insulator body C, the insulator center side is inclined to the horizontal line S by 40 degrees. As shown in FIG. 7, in the insulator body E, the first fold portion 3a is formed longer than the second fold portion 3b, and passes through the lower end edge portion of the first fold portion 3a and the lower end edge portion of the second fold portion 3b. The line L forms an angle of 35 degrees with respect to the horizontal line S, with the insulator center side rising.

As shown in FIG. 8, in the insulator body F, the second fold portion 3b is formed longer than the first fold portion 3a, and the lower end edge portion of the first fold portion 3a and the lower end edge portion of the second fold portion 3b are formed. A line L passing through and is lowered toward the center of the insulator with respect to the horizontal line S 37
It forms an angle of degrees. 6 configured as above
Six or eight types of insulator bodies are connected to each other to form a suspension insulator string 10, and the sound pressure level of noise generated in each suspension insulator string 10 is measured by the above-described test method. By the way, it has been confirmed that there is no great difference in the sound pressure level of noise even if the number of connected insulator bodies is six or eight. Then, as is clear from the test results shown in FIG. 9, the larger the angle of the line L passing through the lower end edge of the first fold portion 3a and the lower end edge of the second fold portion 3b with respect to the horizontal line S, the greater the angle. It is confirmed that the sound pressure level is low. That is, if the line L passing through the lower end edge of the first fold portion 3a and the lower end edge of the second fold portion 3b is at least 35 degrees with respect to the horizontal line S, noise can be substantially prevented. The sound pressure level is almost 9
It is determined whether or not to recognize the noise as noise at a boundary of 5 to 97 dBA.

From the above test results, the insulator body 1 was formed into a shape as shown in FIG. 1 in consideration of ease of manufacturing. When a plurality of insulator main bodies 1 shown in FIG. 1 are connected to form a suspension insulator series 10, the insulator series 10 hardly generates noise even when it receives a strong wind. The present invention is not limited to the above embodiment, and for example, the angle θ of the line L passing through the lower end edge of the first fold portion 3a and the lower end edge of the second fold portion 3b with respect to the horizontal direction line S. To make the
That is, the first fold portion 3a may be formed longer or the second fold portion 3a may be formed.
The folds 3b may be made shorter, the second folds 3b may not be formed, or the second folds 3b may be formed longer than the first folds 3a so that the angle θ is 35 degrees or more. It is also possible to embody the invention by arbitrarily changing the configuration of each part without departing from the spirit of the present invention.

[0015]

As described above in detail, according to the present invention, the excellent effect of preventing the generation of sound due to wind can be exhibited.

[Brief description of drawings]

FIG. 1 is a partially cutaway front view showing an embodiment of a noise prevention insulator embodying the present invention.

FIG. 2 is a side view of a wind tunnel laboratory.

FIG. 3 is a partial cross-sectional view showing an insulator body as a test sample.

FIG. 4 is a partial cross-sectional view showing an insulator body as a test sample.

FIG. 5 is a partial cross-sectional view showing an insulator body as a test sample.

FIG. 6 is a partial cross-sectional view showing an insulator body as a test sample.

FIG. 7 is a partial cross-sectional view showing an insulator body as a test sample.

FIG. 8 is a partial cross-sectional view showing an insulator body as a test sample.

FIG. 9 is a diagram showing a sound pressure level of an insulator main body as a test sample.

[Explanation of symbols]

1 insulator main body, 2 cap portion, 3 fold portion, 3a first fold portion, 3b second fold portion, L line passing through lower end edge of first fold portion and lower end edge of second fold portion, S horizontal direction line.

Claims (1)

[Claims] 1. An insulator in which a cap portion is provided on an insulator main body, and a plurality of folds are concentrically formed on the inner surface of the cap portion in an annular shape, the insulator being provided at the outermost end of the cap portion. 1
Between the fold and the second fold adjacent to the first fold, a line passing through the leading edge of the first fold and the leading edge of the second fold is relative to the horizontal line. The noise prevention insulator is characterized in that the relationship is set so that the angle is at least 35 degrees or more.