Arc quenching chamber for high breaking capacity circuit breakers

In a quenching chamber for a high voltage circuit breaker, a pair of separable contoured contacts are held in abutment by springs along a contact surface, a high velocity arc quenching stream flowable between the contact surfaces during the separation thereof, the contoured surfaces of the contacts defining a Coanda-type nozzle, which controls the flow of the stream along sharp bends in the surfaces, increasing the velocity of the stream and its arc quenching ability.