Abstract: A direct current circuit interrupting apparatus of the type wherein the arc of the circuit interruptor is extinguished by passing an oscillatory current from an oscillating circuit to the interrupted contacts via a switch means which is closed at the time when the circuit interruptor is opened includes a nonlinear resistor comprising a sintered mixture of metal oxides connected in parallel with the oscillating circuit.

Abstract: Within an arc extinguishing chamber are disposed a pair of main electrodes so as to cause a spark starting gap to be defined therebetween. A single auxiliary electrode is also disposed so as to cause reignition in those interspaces between the auxiliary electrode and the respective main electrodes at positions distant from said spark starting gap. Further, paths for supplying therethrough a heated gas to the reigniting spark gaps when the feet at one side of the arcs between the respective main electrodes and the auxiliary electrode have arrived at the prescribed points of the auxiliary electrode are provided.