JPH0628783Y2 - Potential fixing device - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention relates to a case where a high-voltage device is housed in a box body composed of a metal case and a metal lid, such as a ground-mounted switchgear. The present invention relates to a potential fixing device in which a lid and a lid are fixed to a ground potential.

[Conventional technology]

For example, a ground-mounted multi-circuit vacuum switchgear has a structure as shown in FIG.

That is, a cable pit (1) is formed at an appropriate place in the ground passage of the underground distribution line, and the foundation base (2) is formed at the periphery of the upper opening.
The box body (4) of the switchgear is installed on the foundation base (2) through the frame (3).

This box (4) has a metallic case (5) with a painted surface,
It is composed of a metallic lid (6) whose surface is painted and which closes the upper opening of the case (5).

Further, in the box body (4), vacuum valves (7) for three phases and six circuits are installed side by side, and the upper terminal (movable side) of each vacuum valve (7) is arranged for each phase. A bushing (8) that is short-circuited and has its lower terminal (fixed side) penetrating the bottom plate of the box (4).
The underground power distribution cables (9) that are respectively connected to the cable pits and launched from within the cable pit (1) are respectively bushings (8).
It is connected to the.

In addition, (10) is an outer box.

By the way, in the switchgear, it is necessary to fix the outer box (4) accommodating the high-pressure equipment such as the vacuum valve (7) to the ground potential, but the case (5) and the case (5) constituting the outer box (4) and lid
(6) is the case because the surface is painted.
Simply mechanically connecting the lid (6) and the lid (6) with each other cannot electrically connect them.

Therefore, conventionally, as shown in FIG.
Pass the toothed washer (12) through (11), insert this bolt (11) into the bolt insertion hole (13) of the lid (6), and weld the flange (14) to the upper end of the case (5). The lid (6) is mechanically connected to the case (5) with a bolt (11), and the surface of the lid (6) is painted with a toothed washer (16). ) Is scratched, and the lid (6) and the case (5) are electrically connected via the toothed washer (12) and the bolt (11) to fix the potential.

Incidentally, (17) is the coating layer of the case (5).

[Problems to be solved by the invention]

However, in the above configuration, the toothed washer (12) is used to apply the coating layer (1
Since 6) is scratched, there is a disadvantage that rust easily occurs on this scratched part and the contact state of this part becomes unstable.

This invention was made with the above points in mind,
An object of the present invention is to provide a means that can surely fix the electric potential without damaging the painted surface.

[Means for solving problems]

Next, the configuration of this invention will be described with reference to FIG. 1 corresponding to the embodiment.

The potential fixing device according to the present invention comprises a metal case (5) for housing a high-voltage device, a metal lid (6) closing the opening of the case (5), and a bolt insertion of the lid (6). A stainless steel washer (18) directly welded and fixed to the hole (13), and the washer (18)
Coating layers (16) and (17) formed on the surfaces of the lid (6) and the case (5) other than the above, and the lid (6) and the case (5) which are inserted into the bolt insertion holes (13). ) And a metal bolt that is mechanically coupled to and electrically connected through the washer (18).
It is equipped with 11 and.

[Action]

Therefore, in the lid (6), a stainless steel washer (18) having an anticorrosive effect is directly welded and fixed at the position of the bolt insertion hole (13), and the coating layer (on the surface other than this washer (18) 16) is formed, so there is no worry of rusting and the bolt insertion hole
By contacting the washer (18) with the head of the bolt (11) inserted through (13), a stable electrical connection state can be obtained between the bolt (11) and the lid (6). The lid (6) and the case (5) are securely fixed in potential by the (11).

〔Example〕

Next, this invention will be described in detail with reference to FIG. 1 showing one embodiment thereof.

In the figure, the same symbols as those used above indicate the same or corresponding ones, except that the stainless steel flat washer (18) is fixed by welding directly to the position of the bolt insertion hole (13) on the upper surface of the lid (6). The metal bolt (11) through the conductive spring washer (19)
Through the bolt insertion hole (13) and insert the flange (1
It is screwed into the screw hole (15) formed in 4), and the potential of the lid (6) and the case (5) is fixed via the flat washer (18), the spring washer (19) and the bolt (11). That is the point.

Here, the coating of the lid (6) is carried out by welding and fixing the plain washer (18) directly to the lid (6), and then the surface of the plain washer (18) is masked with an adhesive tape or the like. A coating layer (16) is formed on the surface of the lid (6) other than 18).

Therefore, if configured as in the embodiment, the potential of the lid (6) and the case (5) can be reliably fixed without damaging the coating layer (16) of the lid (6).

In the embodiment, the bolt (11) is screwed into the screw hole (15) of the flange (14) so that the lid (6) and the case (5) are mechanically coupled and electrically connected. However, this may be done with metal bolts and nuts.

In this case, the flange (14) is provided with a bolt insertion hole instead of the screw hole (15), and the stainless steel flat washer is welded and fixed directly to the position of the bolt insertion hole on the lower surface of the flange (14). A coating layer (17) is formed on the surface of the case (5) other than the plain washer so that the nut screwed to the bolt (11) is electrically connected to the plain washer.

The invention is not limited to the above-mentioned ground-installed switchgear, but can be similarly applied to fixing the potential of other cases that house high-voltage equipment.

[Effect of device]

As described above, according to the potential fixing device of the present invention, the lid and the case are separated by the stainless washer directly welded and fixed to the position of the bolt insertion hole of the lid and the bolt mechanically connecting the lid and the case. Since it can be electrically connected, it is not necessary to scratch the paint layer with a toothed washer as in the conventional case, rust can be reliably prevented, and the lid and case can be reliably and stably charged. It can be fixed.

[Brief description of drawings]

FIG. 1 is a cutaway front view of essential parts showing an embodiment of a potential fixing device of the present invention, FIG. 2 is a front view of a general ground-mounted multi-circuit vacuum switchgear, and FIG. 3 is a conventional potential fixing device. It is a front view of a part of FIG. (5) …… Case, (6) …… Lid, (7) …… Vacuum valve, (11)
…… Bolt, (13) …… Bolt insertion hole, (16), (17) …… Coating layer.

Claims (1)

[Scope of utility model registration request] 1. A metal case housing a high-voltage device, a metal lid closing an opening of the case, a stainless steel washer directly welded and fixed to a position of a bolt insertion hole of the lid, A coating layer formed on the surfaces of the lid and the case other than the washer, and a metal bolt that is inserted into the bolt insertion hole to mechanically couple the lid and the case and electrically connect via the washer And a potential fixing device having.