Gas circuit breaker

A gas circuit breaker, comprising:

• a sealed container in which arc-extinguishing gas is enclosed;
• a first fixed contactor portion fixed to the sealed container;
• a second fixed contactor portion fixed to the sealed container;
• and
• a movable contactor portion which moves between the first fixed contactor portion and the second fixed contactor portion, and which conducts and breaks current between the first fixed contactor portion and the second fixed contactor portion,
• wherein an arc generated between a fixed arc contactor provided to the first fixed contactor portion and a movable arc contactor provided to the movable contactor portion at a time of current breaking action is extinguished by spraying the arc-extinguishing gas,
• the gas circuit breaker further comprising a gas chamber configured to accumulate unnecessary gas generated from the arc-extinguishing gas sprayed to the arc,
• wherein:
• the sealed container is formed by joining ends of two hollow truncated cone portions both having a large opening diameter via a cylindrical portion between the ends,
• the gas chamber is formed inside the cylindrical portion forming the sealed container, and
• a height of the cylindrical portion is equal to or more than a length of the arc generated between the fixed arc contactor and the movable arc contactor at the time of the current breaking action.