JPS6217330B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an arc extinguishing chamber for a gas cylinder or breaker, and more particularly to an arc extinguishing chamber for a gas cylinder or breaker equipped with an insulated nozzle that is exposed to high-temperature arcs.

The general configuration of the arc extinguishing chamber of a conventional gas vent and disconnector is as shown in FIG. It is formed integrally with the movable arc contactor 3 and the insulating nozzle 4, and is driven by the operating rod 5. The movable arc contact 3 passing through the fixed piston 2 is brought into contact with and separated from the fixed arc contact 6 located at the center of the insulating nozzle 4 by the above drive. The puffer cylinder 1 is placed in an arc-extinguishing gas such as SF6 gas in a closed container, and the space between the puffer cylinder 1 and the fixed piston 2 is filled with such arc-extinguishing gas 7.

Figure 2 shows the movement of the above-mentioned conventional arc extinguishing chamber when the current is cut off. Due to the movement of the puffer cylinder 1 in the direction of the thick arrow, the SF6 gas 7 between the puffer cylinder 1 and the fixed piston 2 is compressed. As a result, the pressure increases, and a gas flow 7a is generated in the arc extinguishing chamber toward the arc 8 generated when the movable arc contact 3 and the fixed arc contact 6 are separated. The arc 8 was cooled by the gas flow 7a and extinguished. At this time, the insulating nozzle 4 was exposed to the high temperature arc 8 and there was a risk of thermal breakdown. Conventionally, this thermal breakdown has been prevented by using a thermally strong material in the nozzle portion of an insulating nozzle, but the problem has been that it is insufficient.

This invention was made in view of the above points, and aims to provide an arc extinguishing chamber equipped with a cooling device, and includes an insulated nozzle made of a porous material and a cooling gas blown out through the porous material of the insulated nozzle. The insulated nozzle of the arc extinguishing chamber is replaced with a porous material, for example, a puffer tank is provided that covers the outside of the insulated nozzle and communicates with the inside of the puffer cylinder, and the insulation is removed by the operation of the puffer cylinder. The nozzle part is actively cooled by flowing cooling gas through the porous material of the nozzle and blowing it out toward the arc.

The present invention will be explained based on the embodiments illustrated below. As shown in FIG. 3, the configuration of the arc extinguishing chamber of the present invention is different from the conventional type in that the insulating nozzle 4 in FIG. The point is that a device is formed that is covered with a puffer tank 9 and blows out cooling gas from a nozzle. The configuration of other parts is the same as in Figure 1, so
In FIG. 3, the same reference numerals as in FIG. 1 are given, and the explanation will be omitted.

To explain the operation, when the blowout is interrupted, the SF6 gas 7 between the puffer cylinder 11 and the fixed piston 2 is compressed, and the main gas 7a is blown onto the arc 8, cooling it and at the same time being integrated with the puffer cylinder 11 to The SF6 gas in the puffer tank 9 through which it is flowing is also compressed and the pressure increases, so the cooling gas is blown onto the arc 8 through the porous material nozzle 14 as a blowout flow 7b indicated by an arrow. At this time, the insulating nozzle 14 made of porous material is cooled by the cooling effect of the gas blowout.

Heat flows into the nozzle through radiation from the arc and heat transfer from the hot gas envelope surrounding the arc.

The blowout cooling mechanism consists of the following two functions.

(a) Decrease in heat transfer coefficient due to the blowout, (b) Heat absorption by the cooling gas passing through the porous wall, Due to the reason (a) of the blowout cooling mechanism, the amount of heat inflow due to heat transfer is reduced. Furthermore, for the reason (b), the nozzle is actively cooled. Furthermore, the blowout flow 7b that has passed through the hole of the insulating nozzle 14 made of porous material is blown onto the arc 8, so that it plays a role of assisting in cooling the arc 8.

The arc extinguishing chamber of the present invention can prevent thermal damage to the nozzle portion, and at the same time, the effect of cooling the arc can be enhanced by the cooling gas blown out from the nozzle.

[Brief explanation of the drawing]

Figure 1 is a partial sectional view showing an example of the structure of a piston-type arc extinguishing chamber in a conventional gas shield disconnector;
The figure is a cross-sectional view showing the situation in the arc extinguishing chamber shown in Fig. 1 when the arc extinguishing chamber is disconnected, and Fig. 3 is a cross-sectional view showing the generation of arc when the arc extinguishing chamber is disconnected. , a cross-sectional view similar to FIG. 2 showing the main gas flow and the blowout flow from the nozzle; 1, 11...Puff cylinder, 2...Fixed piston, 3...Movable arc contactor, 4, 14...
Insulating nozzle, 5... Operating rod, 6... Fixed arc contact, 7... Arc extinguishing gas, 7a... Main gas flow,
7b...Blowout flow, 8...Arc, 9...Patsufua tank.

Claims (1)

[Claims] 1. In the arc extinguishing chamber, which is exposed to the high temperature of the arc generated when the gas tank or disconnector blows, there is an insulating nozzle made of porous material, and a puffer tank that covers the outside of the insulated nozzle and communicates with the inside of the puffer cylinder. and a device for blowing out cooling gas through the porous material of the insulating nozzle.