Electric circuit breaker of minimum liquid type

Claim 1

Electric circuit breaker of the minimum liquid type having an elongated, substantially vertical extinguishing chamber, an arc channel running in the longitudinal direction of said chamber, a stationary contact in the upper end of the channel, a movable contact displaceable through said channel to engage said stationary contact, at least one pressure accumulating space in said extinguishing chamber, said pressure accumulating space being partly filled with liquid and including a closed gas-filled space, a plurality of outlet channels from said pressure accumulating space crossing said arc channel, the uppermost of said outlet channels being arranged immediately below the stationary contact, said outlet channels being uncovered by the movable contact when the circuit breaker opens, in which the invention comprises at least one exhaust channel arranged inside said extinguishing chamber and an expansion chamber arranged above the extinguishing chamber, said outlet channels opening into said exhaust channel and said exhaust channel leading to said expansion chamber, said expansion chamber being partly filled with gas, said pressure accumulating space and said exhaust channel extending along in the direction of said arc channel at substantially the same distance therefrom, at least one liquid-filled space below the outlet channels, said liquidfilled space surrounding the arc channel and being in free communication therewith.