GAS CIRCUIT-BREAKER

A reduction of the temperature of a blown gas, an improvement of a durability and a reduction of a maintenance frequency, a reduction of a current cutoff time, a reduction of drive and actuation energy, and a stabilization of a gas flow are accomplished. A pair of stationary arc electrodes 35a, 35b is disposed in a sealed container filled with an arc-extinguishing gas 1 to face with each other. A trigger electrode 34 in a rod shape with a smaller diameter is disposed between the stationary arc electrodes 35a, 35b so as to be freely movable. An insulation nozzle 81 is disposed so as to surround the trigger electrode 34. An accumulating chamber 42 to reserve the arc-extinguishing gas 1 having undergone pressure increase is provided, and a switch causing the accumulating chamber 42 to be in a closed state or a released state is provided. The switch includes gaps between the arc electrode 35b and the trigger electrode 34, and between the insulation nozzle 81 and the trigger electrode 34, and by closing the gaps by the moved trigger electrode 34, a closing component 45 is formed.