Electric circuit breaker of the type using an arc quenching fluid with

Abstract

In an electric circuit breaker of the type using an arc quenching fluid with pressure self-generating by the breakdown of the fluid due to the same arc, comprising, inside a tightly sealed insulating casing filled with the extinguishing fluid, in particular with such a gas as sulphur hexafluoride, two plate-shaped current bearing connections, of which one supports a stationary main contact and a tubular stationary arc contact, and the other is provided with a guide for a stem supporting a movable main contact and a rod-shaped movable arc contact, a drive mechanism for moving said stem from a closure position to an opening position of the contacts and vice-versa, a first extinguishing fluid collecting and compression chamber surrounding the stationary arc contact and having an outlet opening suitable to be closed by said movable arc contact, at least a further collecting and compressing chamber having an outlet opening, as well as means for closing said outlet opening of said further chamber, the outlet openings of said first chamber and of the further chamber are coaxial and aligned with the axis of the rod-shaped movable arc contact movement, and this movable arc contact is the means for closing the outlet opening of the further chamber, the outlet opening of the first chamber leading to the further chamber.