Abstract: A compressed gas circuit breaker, especially a blasting piston ("puffer") circuit breaker having a movable nozzle of insulating material which surrounds the quenching gap and, by means of pressure springs, forms a stop for closing off the gas flow canal, in which a guide is provided coupling at least one pressure spring to the relative motion of the contacts in such a manner that its effect on the insulating material body is cancelled as soon as the minimum quenching distance has been reached during the opening of the breaker, preventing blasting of the arc before the switch contacts have reached their quenching distance.

Abstract: An apparatus and a method for quenching an arc in a gas flow circuit breaker having both a permanent current contact and an arc contact system, wherein the motion of the contacts is made current dependent, thereby delaying or accelerating the duration of the opening of the contacts of the arc contact system as a function of the current so as to shorten the arc duration and correspondingly to increase the quenching capacity of the breaker.

Abstract: An improved arc quenching arrangement for a gas-flow circuit breaker apparatus of the type including a housing; a body of electrical insulation material disposed within the housing and forming an arc quenching gap therewithin; at least one gas flow canal disposed within the body of insulation material for directing a quenching gas from a space within the housing to the vicinity of the quenching gap; fixed and movable electrical contacts disposed within the housing adjacent the housing quenching gap; and a check valve disposed in the flow canal for permitting the flow of the arc quenching gas only from the space within the housing to the quenching gap formed by the body of insulation material. The improvement of the invention comprises the extension of the gas flow canal to the arc quenching gap formed by the body of insulation material and the disposition of the check valve at the end of the flow canal at the arc quenching gap. An improved arc quenching effect for large current flow is thereby achieved.

Abstract: In a quenching arrangement in a gas flow circuit breaker of the type which has at least one check valve in a flow channel leading through a portion of the insulating material to the quenching gap, at least one overflow channel having therein a pressure relief valve is installed parallel to the quenching gap to couple the higher pressure chamber in which the quenching gas is contained with the low pressure chamber to which gas discharges after quenching.

Abstract: An improved method for quenching an arc in an AC circuit breaker having an arc chamber in which the arc rotates in a quenching medium between open electrodes having ends close together in which the arc is caused to generate during its rotation, through a heating of the quenching medium, an over-pressure which is maintained beyond the zero crossing of the AC current with the gas flow produced by the over-pressure use for blasting the arc in the nozzle. Various embodiments for use in medium and high voltage switching installations which permit the switching of large currents with a simple and inexpensive arrangement are illustrated.

Abstract: An arrangement for quenching an arc in a gas-flow circuit breaker in which at least one check valve is arranged in a flow canal leading through a portion of the insulating material to the quenching gap, the check valve insuring that a reverse flow from the quenching gap into the inlet canals of the quenching gas is prevented.