JPS5926735Y2 - closed switchboard - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a closed switchboard in which a pressure relief device is provided with a ventilation vent.

Conventionally, when a flash fault occurs inside a closed switchboard, the high-temperature, high-pressure gas generated by the arc energy at that time is released into the planned space outside the switchboard via a pressure relief device installed in the closed switchboard. ing.

This is because if the pressure inside the panel increases and the closed switchboard itself is damaged, it could cause damage or danger to surrounding equipment and panel monitors, so by reducing the internal pressure of the closed switchboard as much as possible, accidents can be prevented. This is because it is necessary to prevent this from happening.

Normally, the pressure relief device is installed on the ceiling of the panel, and the high-pressure gas inside the panel is blown out from the ceiling of the panel toward the upper space.
In order to keep the increase in pressure inside the panel as small as possible, it is necessary to make the pressure relief opening as wide as possible.

However, since a vent for ventilation of air inside the panel is generally provided in the panel ceiling, there is a drawback that the wider the pressure relief opening is, the more difficult it becomes to secure a vent.

FIGS. 1 and 2 show details of the panel ceiling of a conventional closed switchboard and the ventilation holes provided in the panel ceiling.

As shown in the figure, a part of the panel ceiling board 1 is cut out, and the cut out part can be covered, and the pressure release plate 2 is attached to the panel ceiling board 1 through the hinge 3.
At the same time, a metal lath or perforated iron plate 6 is placed over the cut-out portion of the vent 5, and the top thereof is covered by a vent cover 4 attached to the panel ceiling board 1. That's what happens.

If the pressure inside the panel increases rapidly, the pressure increase cannot be suppressed by the vent 5 alone, so the pressure relief plate 2 serving as a pressure relief device is rotated around the hinge 3 by utilizing the pressure increase. By doing so, the pressure increase inside the panel can be quickly suppressed.

In this case, it is clear that the pressure increase is more effective as the pressure relief plate 2 is larger, that is, the pressure relief opening is larger, so it can be said that the larger the pressure relief opening is, the heavier the vehicle is.

However, as mentioned above, since a vent is also provided in the panel ceiling plate, the larger the pressure relief opening is made, the less room there is for the vent to be provided.

The object of the present invention is to provide a closed switchboard having a pressure relief device with a large pressure relief opening and a vent on a panel ceiling board in a limited space.

The present invention will be explained below with reference to FIGS. 3 to 6.

The closed switchboard according to the present invention is shown in FIGS. 3a and 3b.

Of these, FIG. 3 is a perspective view of the essential parts extracted when the one shown in FIG. 3a is viewed from the opposite direction.

As shown in the figure, the closed switchboard has a rectangular parallelepiped shape with a door 7, and a pressure relief plate 2 is rotatably attached to the panel ceiling plate 1 as the panel ceiling using a hinge 3 as in the conventional case. The other end 2a of the pressure relief plate 2, which faces the side on which the pressure relief plate 3 is attached, is brought into contact with the outer frame 5a of the ventilation frame 5b provided on the panel ceiling plate 1.

In this configuration, the side plate 8, which is provided upright on the panel ceiling plate 1, is used to support the pressure relief plate 2 and at the same time attach the ventilation frame 5b on which the metal lath or perforated iron plate 6 is stretched. Although it may be attached to the pressure relief plate 2 independently, it is sufficient to raise it from the panel ceiling plate 1 when forming the pressure relief opening 1a.

Furthermore, in the case where the ventilation frame 5b is made of metal lath, the ventilation frame 5b with a metal lath welded to the back side is attached to the side plate 8 as shown in FIG.
When using a perforated iron plate, the ventilation frame is omitted, for example, as shown in Figure 5a.
After forming as shown in FIG. 5, it may be attached to the back side of the ceiling plate 1 and the inner surface of the side plate 8 by welding as shown in FIG.

Under normal conditions, the pressure relief plate 2 is at the position indicated by the solid line as shown in Figure 3C, and the air inside the panel is ventilated through the ventilation frame 5b, but the pressure inside the panel suddenly increases If this happens, the pressure will cause the pressure relief plate 2 itself to rotate, and the high-temperature, high-pressure gas can be quickly dissipated into the upper space.

FIGS. 6a and 6b show a perspective view and a cross-section of essential parts when the pressure relief device according to the present invention is applied to a busbar box.

Although the present invention is specifically directed to closed switchboards, it is not limited thereto and is generally applicable to any device that is likely to cause a similar situation.

If the length of the busbar box is relatively short, pressure relief can be expected at the closed switchboards located at both ends of the busbar box, but if it is very long, this cannot be expected and a considerable amount of pressure will be generated at that part. This can result in damage to the power distribution equipment inside the switchboard that is not directly involved in the accident.

Therefore, if the pressure relief device according to the present invention is applied to the ceiling plate 10 of such a busbar box 9, damage, damage, and danger can be minimized.

Since FIG. 6 is similar to FIG. 3C, no particular explanation is required.

Although the present invention is as described above, it is not limited to the illustrated example and can be implemented.

For example, a vent hole covered with a cover may be provided in a suitable portion of the pressure relief plate itself.

The point is that the vent can be provided integrally or integrally with the pressure relief device without taking up space on the panel ceiling board.

As explained above, the present invention allows the vent to be integrated into the pressure relief device without taking up space on the panel ceiling, so it is possible to free up a lot of space for the pressure relief device. This has the effect of minimizing damage, damage, or danger caused by increases in internal pressure of the panel.

[Brief explanation of the drawing]

Figures 1 and 2 are perspective views of the panel ceiling of a conventional closed power distribution board and details of the vents provided in the panel ceiling. Figures 4 and 5 a and b are illustrations showing the installation of the metal lath and perforated iron plate stretched over the vent, and Figures 6 a and b are It is a diagram showing a perspective state and a cross section of the main parts when the pressure relief device according to the present invention is applied to a busbar box. 1... Panel ceiling plate, 1a... Pressure relief opening, 2... Pressure release plate, 3... hinge, 5... vent, 5b... ventilation frame.

Claims (1)

[Scope of utility model registration request] In a closed switchboard equipped with a pressure relief device on the panel ceiling plate, the pressure relief device covers the pressure relief opening 1a opened in the panel ceiling plate 1,
Consisting of a pressure relief plate 2 whose one end is pivotally connected to the panel ceiling plate 1 by a hinge 3, and a ventilation frame 5b with which the other end 2a of the plate 2 abuts and communicates with the pressure relief opening 1a. A closed switchboard featuring: