JP3345838B2 - Insulator arm of power transmission tower - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an insulator arm of a power transmission tower.

[0002]

2. Description of the Related Art FIG. 4 shows an example of a transmission line tower having arms formed by insulators. 1 is a tower main body, 2 is an insulator arm composed of a compression insulator 3 and a tension insulator 4. The compression insulator 3 and the tension insulator 4 are connected at the tip, and the compression insulator 3 is disposed substantially horizontally and the tension insulator 4 is disposed obliquely on the compression insulator 3. The proximal end of the compression insulator 3 and the proximal end of the tension insulator 4 are connected to the tower main body 1 respectively.

FIG. 5 shows a more specific configuration of the insulator arm 2 described above. The distal ends of the compression insulator 3 and the tension insulator 2 are connected by a connection pin 11, and a suspension clamp 13 supporting a power transmission line 12 is suspended from the connection pin 11. The base end of the compression insulator 3 is rotatably connected to the tower main body 1 by an insulator terminal fitting 14 and a connection pin 15. On the other hand, the base end of the tensile insulator 4 is
6, the connection pin 17, the connection fitting 18, the connection pin 19, the clevis 20 and the like are connected to the tower main body 1.

[0004]

The tip of the insulator arm can be moved to some extent in the line direction by the rotation of the base end so as to absorb the difference in wire tension between adjacent diameters. However, in the conventional insulator arm, since the direction of the connection pin serving as the rotation center of the compression insulator and the direction of the connection pin serving as the rotation center of the tension insulator are different, when the insulator arm rotates due to a change in the tension of the transmission line, the connection portion is twisted. Occurs, and the abrasion of the connecting member and torsion of the insulator shaft occur.
In the long term, there is a possibility that the arm may be damaged.

If the tip of the insulator arm is strongly pulled in the line direction due to a disconnection accident or the like, an extremely large bending moment is applied to the insulator arm, and there is a risk that the insulator or the connecting member may be damaged. In particular, in the case of a disconnection accident, if the insulator arm is destroyed at one tower, the insulator arm is also destroyed at the adjacent tower,
Since there is a possibility that so-called cascade destruction may occur in which the destruction spreads in a chain, the insulator arm also needs to take measures against this.

[0006]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and has a structure in which a compression insulator and a tension insulator are connected at a distal end, and a base end of the compression insulator and a tension insulator are connected. In the insulator arm of the power transmission tower formed by connecting the base end of the insulator to the tower body, the rotation center axis of the portion connecting the base end of the compression insulator to the tower body and the base end of the tension insulator are connected to the tower body. The rotation center axes of the portions are matched.

[0007] Further, it is preferable that a stopper for restricting the rotatable range of the compression insulator to be smaller than the rotatable range of the tension insulator is provided at a portion connecting the base end of the compression insulator to the tower main body.

[0008]

According to the above construction, when the tip of the insulator arm is pulled in the line direction due to a change in the tension of the power transmission line, the insulator arm rotates smoothly. Can be prevented from being damaged due to wear and the like.

Further, if a stopper is provided to limit the rotatable range of the compression insulator, the compression insulator will be damaged first if a strong bending moment is applied to prevent the insulator from being damaged due to a disconnection accident or the like. As a result, the transmission line is suspended by a single tension insulator. For this reason, the movable range of the tension insulator is further expanded, and the tension insulator is mainly in a state of only receiving the tension, thereby avoiding breakage, thereby making it possible to prevent a chain breakage.

[0010]

Embodiments of the present invention will be described below in detail with reference to the drawings. 1 and 2 show one embodiment of the present invention. In FIG. 1, the same parts as those in FIG. 5 described above are denoted by the same reference numerals. The insulator arm 2 is characterized by a connecting pin 15 for connecting the insulator terminal fitting 14 of the compression insulator 3 to the insulator support fitting 21 on the tower main body 1 side, and a tension insulator 4.
The connecting pin 17 for connecting the insulator terminal fitting 16 to the insulator support fitting 22 on the side of the tower main body 1 is arranged on the same axis. As a result, the insulator arm 2 is connected to the connecting pin 1
Since it becomes possible to rotate smoothly around the center 5 and 17, even if the transmission line 12 is pulled in the line direction due to a change in tension, the transmission line 12 will not be forced.

Another characteristic of the insulator arm 2 is that
As shown in FIG. 2, the insulator supporting bracket 2 on the side of the compression insulator 3
First, a stopper 23 for regulating the rotatable range of the compression insulator 3 is formed. This restricts the rotatable range of the compression insulator 3 to be smaller than the rotatable range of the tension insulator 4. As a result, when a particularly strong tensile force in the line direction is applied due to a disconnection accident or the like, when the compression insulator 3 reaches the limit of the rotatable range, it receives a large bending moment and breaks first. For this reason, tension insulator 4
The degree of freedom is further expanded, and only the tensile force acts on the tensile insulator 4, so that only the tensile insulator 4 can be prevented from breaking, and the risk of cascade breaking or the like can be reduced.

In order to ensure that only the compression insulator 3 breaks when the compression insulator 3 reaches the limit of the rotatable range, the compression insulator 3 is subjected to an excessive bending moment exceeding the bending strength of the compression insulator 3. The base 3 (insulator rod or insulator terminal fitting) may be designed to be bent and broken first.

As the compression insulator 3 and the tension insulator 4, a polymer insulator in which a polymer jacket is applied to an FRP rod or a long-porcelain insulator made of porcelain can be used. It is preferable to use a polymer insulator from the viewpoint of non-scattering property when broken.

In the above embodiment, the connecting portions on the base end side of the compression insulator 3 and the tension insulator 4 are connected to the insulator terminal fitting 1.
Although the eyepieces 4 and 16 are made of eyes and the insulator support members 21 and 22 are made of clevis, which may be clevis or eye. Further, the connecting portion on the base end side of the tensile insulator 4 only needs to have a large rotatable range, and therefore may be configured by tying the U clevis 24 and the U clevis 25 as shown in FIG.

[0015]

As described above, according to the present invention, when the tip of the insulator arm is pulled in the line direction due to the change in the tension of the power transmission line, the insulator arm rotates smoothly, so that the insulator arm cannot be used. It is possible to prevent the insulator or the connecting member from being damaged due to abrasion, thereby improving long-term reliability.

If a stopper is provided to limit the rotatable range of the compression insulator, when a disconnection accident or the like occurs, the rotation of the compression insulator is restricted by the stopper, and the compression insulator is broken first. Since the spread and the tension insulator are mainly in a state of only receiving the tension to avoid breakage, a chain breakage can be prevented.

[Brief description of the drawings]

FIG. 1 is a front view showing an embodiment of an insulator arm according to the present invention.

FIG. 2 is a sectional view taken along line AA in FIG.

FIG. 3 is a front view showing another example of the connection structure on the proximal end side of the tension insulator in the insulator arm of the present invention.

FIG. 4 is a front view showing an example of a transmission line tower having an insulator arm.

FIG. 5 is a front view showing a conventional insulator arm.

[Explanation of symbols]

 1: Tower main body 2: Insulator arm 3: Compression insulator 4: Tension insulator 11: Connection pin 12: Transmission line 13: Suspension clamp 14: Insulator terminal fitting 15: Connection pin 16: Insulator terminal fitting 17: Connection pin 18: Connection fitting 21, 22: insulator support bracket 23: stopper

Claims (2)

(57) [Claims] (1) connecting a compression insulator and a tension insulator at a tip thereof;
In the insulator arm of the transmission line tower connecting the base end of the compression insulator and the base end of the tension insulator to the tower body respectively,
An insulator arm for a power transmission tower, wherein a center axis of rotation of a portion connecting a base end of a compression insulator to a tower main body coincides with a center axis of rotation of a portion connecting a base end of a tension insulator to a tower body. 2. The insulator arm according to claim 1, wherein a stopper for restricting a rotatable range of the compression insulator to be smaller than a rotatable range of the tension insulator is provided at a portion connecting the base end of the compression insulator to the tower main body. Characterized by that.