JPS628907B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in the internal structure of a lightning arrester.

Figure 1 shows an example of a conventional internal structure, in which a lightning arrester element 2 is placed in a lightning arrester container 1 made of metal or porcelain, and a metal conductor 3B integrally formed in the center of an insulator 3A on the energized side. The ground side is positioned by the bottom cover protrusion 4A of the metal bottom cover 4, and is fixed by the compressive force of the spring 5. The lightning arrester element 2 is constructed by stacking a plurality of series gap 6 and characteristic element 7 according to the rated voltage, for example, as shown in FIG. The end portion of the holder is fixed with a nut 10. An insulating gas 11 is sealed inside the container 1 . 12 is a mounting bolt.

In such a surge arrester, the weight of the surge arrester element 2 is
If M is the acceleration received from the truck etc. on the tower during transportation, then the compressive force W of the spring 5 is expressed by the formula W>S _f・M・G where S _f >1 and the safety factor. If these conditions are not satisfied, the arrester element 2 may move within the container 1 during transportation or, in the worst case, be destroyed by vibration. Furthermore, as the rating of the lightning arrester becomes higher, the arrester element 2 becomes longer and the weight M becomes larger, so it is necessary to increase the compressive force W of the spring 5.

However, if the compressive force W becomes too large, not only will the insulating rod 8 not be able to withstand it mechanically, but even if it can withstand it during manufacture, it will deform and break over many years due to creep of the insulator. If the insulating rod 8 is deformed, the series gap 6 and the characteristic element 7 will also be subjected to an excessive compressive force W, and these will also be destroyed.

On the other hand, when the rating is high and the lightning arrester element 2 becomes long and large, the natural frequency is lowered and resonance is more likely to occur during transportation, resulting in a disadvantage that it is more likely to be destroyed.

The present invention provides a high-rated lightning arrester by dividing a lightning arrester element into a plurality of divided sections, and providing an intermediate holding member at the connecting portion between the divided sections, thereby eliminating the drawbacks of the prior art.

Hereinafter, one embodiment of the present invention will be described based on the drawings.

FIG. 2 is a cross-sectional view showing one embodiment of the present invention. In the figure, the same numbers as those in FIG. 1 indicate the same or similar items.
is divided into a plurality of sections, and is composed of a divided section 2A and a divided section 2B.The electrical side of the divided section 2A is completely fixed to the joint 3C of the insulating spacer 3 with, for example, a bolt 12, and the divided section 2B is The ground side of is similarly completely fixed to the bottom cover 4 with, for example, bolts 12. The insulating spacer 3 and the bottom cover 4 are each fixed to the container 1 with bolts 12. Division 2A
2B, the electrical and mechanical connections between the first support part A1 and the second support part A2 are as shown in FIG.
In detail, it has an intermediate support member 14 fixed to the flange bottom cover 13 attached to the flange 1A of the container 1, and a sliding base 15 fixed to the intermediate support 14. , the divided section 2B is arranged so as to constitute a sliding part with a fitting structure that allows sliding as shown in the figure through the through hole 16 provided in the sliding table 15.
It consists of a sliding tool 17 attached to the slider 17, a spring 5 attached between the divided section 2A and the divided section 2B, and the like, and a spring 5 attached between the divided section 2A and the divided section 2B. Slide tool 1 is installed in the through hole.
7 is fitted. Electrically, conductor 3B → division 2A → end plate 9 → spring 5 → sliding base 15 → spring 5
→Sliding tool 17→Divided section 2B→Bottom cover 4. The rest of the structure is the same as that of the conventional lightning arrester shown in FIG. 1, and although not shown in FIG. is included.

In the lightning arrester configured in this manner, the arrester element 2 is divided, and the springs 5 supporting the divided sections are each supported by the intermediate support 14, so that the spring pressures of the divided sections do not interfere with each other. Therefore,
The spring 5 only needs to bear the weight of each divided section, and since each divided section is fixed at one end, the spring pressure can be very small.

On the other hand, by dividing the insulating rod 8 into sections, the holding insulating rod 8 does not need to be long and can be manufactured, and the spring pressure can be kept low.
No problem arises in terms of mechanical strength.

In addition, by dividing the device into sections, it is possible to avoid the device from becoming long and heavy, so the natural frequency can be increased, and resonance during transportation can be prevented.

The sliding table 15 of the intermediate support 14 slides with the sliding tool 17 attached to the divided section 2B when the container 1 and the divided sections 2A and 2B exhibit different expansion and contraction in response to a change in the temperature of the outside world. Since the difference in expansion and contraction is absorbed by the spring 5, the electrical connection is maintained, and although the sliding tool 17 and the sliding part 15 can slide in the axial direction, they cannot slide in the direction perpendicular to the axis. Since it does not move, mechanically the spring pressure only changes slightly and no problems occur.

Further, in the divided section 2A, since the end plate 9 is held by the sliding tool 17 so as to be slidable in the axial direction as described above, there is no problem electrically or mechanically.

In the present invention, an example has been described in which the lightning arrester element is divided into two parts, but the divisions are 2A, 2A,
It may be divided into three parts like 2B and 2C, and further divided into three parts.
It is possible to have more than division.

In addition, the intermediate support stand, sliding stand, and sliding tool do not need to be as shown in Figure 2, as long as they are structured so that they can slide in the direction of the axis that connects the divided sections and do not move in the direction perpendicular to the axis. good.

Next, FIG. 4 shows an equivalent circuit of an application example of the lightning arrester of the present invention.
As shown in the figure, a capacitor 18 is mounted in or around the intermediate support 14, with one of the capacitors 18 being electrically connected to the divided section and the other to the container 1. In this case, the container 1 is made of metal or a conductive material.

That is, Fig. 4a shows an example in which the arrester element is divided into two and the intermediate support forms a capacitor C or has a built-in capacitor C, and Fig. 4b shows an example in which the arrester element is divided into three and the intermediate support forms a capacitor C or has a built-in capacitor C. both form capacitor C or capacitor C
FIG. 4c shows an example in which the support is similarly divided into three parts, but only one of the intermediate supports forms the capacitor C, or the capacitor C is built in.

In the above circuit configuration, it is the same as connecting a capacitor in parallel with one of the divided sections, so the impedance of the divided section with capacitors connected in parallel becomes lower in response to impulsive voltages such as lightning surges. , the voltage is shared more among the remaining divisions, so that the discharge voltage can be lower than if no capacitor was connected. Further, adding a capacitor to the intermediate support 14 has the same effect even if there are a plurality of intermediate support pedestals, and the capacitor may be added to all or selectively of the intermediate support 14.

As described above, according to the present invention, the pressure contact force of the connection member for holding the surge arrester element can be made very small, so the strength of the surge arrester element can be ensured sufficiently, and since it can be divided into sections, it can be highly rated. Even if the insulating rod is used as a lightning arrester, it is possible to avoid the insulating rod from becoming too long, and therefore the production limit of the insulating rod can be avoided.

In addition, by dividing into sections, it is possible to make the natural frequency higher than in the case of an integrated structure, and resonance with a transport vehicle during transportation can be avoided.

Furthermore, the difference in expansion and contraction due to temperature between the container and the arrester element can be avoided by the main holding member, and there is no need to reduce the mechanical strength.

Further, by making the support part constituting the intermediate holding member made of dielectric material, various effects can be obtained, such as improving discharge characteristics.

[Brief explanation of the drawing]

Figure 1 is a simplified cross-sectional view of a conventional lightning arrester;
The figure is a simplified sectional view showing a lightning arrester which is one embodiment of this invention, FIG. 3 is a simplified sectional view showing another embodiment of this invention, and FIGS. 4 a to 4 c are for explaining application examples of this invention. FIG. Note that the same reference numerals in the figures indicate the same or equivalent parts. In the figure, 1 is a container, 2 is a lightning arrester element, 2A to 2C
is a divided section, 3 is an insulating spacer, 4, 13 is a bottom cover, 5 is a spring (connecting member), 8 is an insulating rod, 9
is an end plate, 14 is an intermediate support base, 15 is a sliding base, 18
is a capacitor.

Claims (1)

[Claims] 1. A lightning arrester comprising a container made of a conductive material, both ends of which are connected to an insulating spacer and a bottom cover provided at both ends of the container, and which are divided into a plurality of sections and arranged on a coaxial line. a sliding base made of a conductive material provided between the lightning arrester elements; an intermediate support base fixed to the inner side of the container; and a sliding base fixed to the end plate of one of the lightning arrester elements a sliding tool axially movably engaged with the sliding base and fitted into a through hole provided in the end plate of the other lightning arrester element; both surfaces of the sliding base and opposing end plates of the lightning arrester element; A lightning arrester comprising a spring contracted between each spring. 2. The lightning arrester according to claim 1, comprising an intermediate support made of a dielectric material. 3. The lightning arrester according to claim 1, comprising an intermediate support fixed to the bottom cover of the flange provided on the side of the container.