Abstract: A hybrid circuit-breaker for interrupting currents having high DC components, said hybrid circuit-breaker comprising a compressed-air circuit-breaker that re-closes automatically, and a sulfur hexafluoride circuit-breaker, the circuit-breakers being disposed in series.

Abstract: A valve for the escape of compressed air in order to extinguish the electric arc between the moving contacts of a circuit-breaker. The arrangement includes an intermediate moving structure between the control rod and the compensated force valve with two seats, said structure being constituted by a cylinder integral with one of the seats and a piston which cooperates with the control rod in order to transmit a rapid and reliable control command.

Abstract: A gas-blast circuit-breaker which includes at least one cutout chamber including at least one blast valve with two seats, one of which, when the valve is opened, is situated on the blast-gas exit path. The breaker is characterized in that a moving slide valve is associated with the valve, in such a manner that opening the valve causes a slightly delayed movement of the slide valve in the same direction as the valve and along the same axis, so that it masks said valve seat situated on the exit path of the hot blast-gases arriving from extinguishing the arc when the blast-gases flow towards the outside; the slide valve being opened by compressed gas contained in the gas-blast circuit-breaker.

Abstract: An articulated contact finger of very high voltage gasblast circuit-breaker. It is characterized in that the pin on which the finger is articulated is disposed between the contact piece and a spring which provides the force required at the contact point, a first support of the stationary articulation pin being situated between the articulation pin and the spring, said spring being disposed between said first support and a second support providing fixing means for the flexible connection connected to the contact point.