Abstract: In order to provide a gas circuit breaker capable of reducing a remarkable degradation of dielectric strength in the vessel caused by hot gas and which can be downsized, the present invention is characterized by a hot gas discharge mechanism of the movable opening/closing mechanism, which is designed to ensure that the hot gas separated and fed to a movable opening/closing mechanism is discharged from an exhaust outlet 19b toward the side opposite to the puffer chamber 26 of the gas discharge chamber 28 formed on the rear of the puffer chamber 26, and gas is discharged toward the inner surface of the vessel 4 through the exhaust outlet 23b after gas temperature and velocity have been interrupted by convection of the gas in the puffer chamber 26. This structure interrupts a remarkable degradation of dielectric strength in the vessel resulting from direct blowing of hot gas onto the inner surface of the vessel 4.

Abstract: In order to provide a gas circuit breaker capable of reducing a remarkable degradation of dielectric strength in the vessel caused by hot gas and which can be downsized, the present invention is characterized by a hot gas discharge mechanism of the movable opening/closing mechanism, which is designed to ensure that the hot gas separated and fed to a movable opening/closing mechanism is discharged from an exhaust outlet 19b toward the side opposite to the puffer chamber 26 of the gas discharge chamber 28 formed on the rear of the puffer chamber 26, and gas is discharged toward the inner surface of the vessel 4 through the exhaust outlet 23b after gas temperature and velocity have been interrupted by convection of the gas in the puffer chamber 26. This structure interrupts a remarkable degradation of dielectric strength in the vessel resulting from direct blowing of hot gas onto the inner surface of the vessel 4.