JPS6026433Y2 - arc extinguisher - Google Patents

Description

[Detailed explanation of the idea] The present invention relates to an arc extinguishing device.

In a conventional arc splitting (dividing) type arc extinguishing device, the arc is split by the grid 4 when a short circuit is interrupted, but the grid 4 may be melted by the arc energy at this time.

That is, this molten material 7 is moved to the grid back plate 5 by the arc gas pressure.
A portion of the molten material 7 is scattered toward the exhaust hole 6 through the gaps (holes), but a portion of the molten material 7 may remain fixed to the grid 4.

This state is illustrated in FIGS. 1 and 2.

However, in the arc extinguishing chamber A of this arc extinguishing device, the H dimension in Figure 2 becomes large due to the number of grids 4, but the H dimension must be made as small as possible due to the dimensional constraints of the breaker body and mechanical parts. Sometimes.

In such a case, the grid melt 7 may connect between the grids 4 and form a bridge due to arc interruption.

As a result, these grids 4 have the same potential, which impairs the arc splitting function, and the dielectric strength between the upper and lower running plates 1 and 2 is reduced due to bridging of the grids 4.

It is possible to eliminate this problem by increasing the interval between the grids 4, but in that case, the total height H also increases, resulting in a disadvantage that dimensional restrictions become larger.

In the figure, 3 is a movable contact of the breaker, and 8 is a fixed contact.

The present invention was developed in view of the above-mentioned drawbacks, and its purpose is to prevent bridging of the grids by molten material without increasing the overall height of the arc extinguishing chamber and increasing the grid spacing. To provide an arc extinguishing device that is easy to use, has a simple structure, does not require much reduction in the heat capacity and magnetic effect of the grid itself, and is easy to process.

The present invention will be explained below with reference to examples.

FIGS. 3a and 3b show one embodiment, and the grid 4 shown in FIG. There are steps on the upper and lower surfaces of the portion 4a.

However, when removing the soil constituting the arc extinguishing chamber A, if a plurality of grids 4 are arranged downwardly in parallel at regular intervals, each end portion 4a
This means that the distance between the front parts 4b can be made larger than the distance between the front parts 4b.

In this way, even if the grids 4 are melted by the arc energy and the melt is stuck to the terminal end 4a, bridging between the grids 4 can be prevented.

FIGS. 4a and 4b show another embodiment of the present invention, and in this embodiment, as shown in FIG. 4a, the end portion 4a of the grid 4 is tapered so that the wall thickness becomes thinner toward the end. It is something.

FIG. 4 shows a state in which the arc extinguishing chamber A is constructed by arranging the grids 4 at regular intervals upward and downward.

In this invention, only the end portions of each grid are made thinner, and the distance between the end portions of the grids arranged at regular intervals above and below is increased compared to the front portion, so even if the grids are melted by arc energy, Even if the molten material sticks and remains at the terminal end, the distance between the terminal ends can be substantially increased to prevent bridging caused by the molten material, and the total height of the arc extinguishing chamber can be increased to increase the grid spacing. Since it is not necessary, there is no problem due to size constraints1.
Moreover, only the thickness of the end of the grid was changed,
It has the advantage that the heat capacity and magnetic effect of the grid itself are not significantly reduced, the arc extinguishing performance is not degraded, and the grid is easy to process.

[Brief explanation of the drawing]

Fig. 1 is a schematic configuration diagram of a conventional arc extinguishing device, Fig. 2 is a state explanatory diagram of the same as above, Fig. 3a is a perspective view of a grid of an embodiment of the present invention, and Fig. 3 is an extinguisher of same as above. A schematic configuration diagram of the arc device, FIG. 4a is a perspective view of the grid of another embodiment of the present invention, FIG.
The figure is a schematic configuration diagram same as the above, and 4 is a grid, 4a is a terminal portion, and 4b is a front portion.

Claims (1)

[Scope of utility model registration request] In the arc splitting type arc extinguishing device, only the end portions of each grid are made thinner, and the distance between the end portions of the grids arranged at regular intervals above and below is made larger than the front portion. Arc extinguishing device.