| 摘要 |
A switch, preferably for switching medium voltages, includes a structure which creates a gas-blast to quench an arc drawn between two separating contact pieces of the switch. The gas-blast is created solely by the quenching gas which is heated by the arc, without auxiliary pressure creating mechanisms. The gas blast is sufficiently powerful to cut off high and low currents without use of pressure-controlling valves. The result is realized via a flow-off pipe located between a space where the arc develops and a gas exhaust space. One end of the flow-off pipe opens into the exhaust space. The size of the flow-off pipe is determined in part by the speed of propagation of a pressure wave which is formed in the arc space during the heating phase of the arc and the length thereof is deliberately selected such that the pressure gradient between the heated quenching gas and the arc space is maximized. |
