Puffer type circuit breaker with arcing chamber, auxiliary shunting

Abstract

Arranged in the continuation of an arcing chamber (16) bounded by consumable rings (32a, 32b) are pressure chambers (25a, 25b) which are connected in each case to a heating volume (18), which concentrically surrounds the arcing chamber (16), via a return channel (28; 28b), which is rotationally symmetrical with reference to the switching axis and is at least initially of increasing cross section, and a non-return valve (29a; 29b). A circumferential blowout slot (19) opening into the arcing chamber (16) between the consumable rings (32a, 32b) issues from the heating volume (18). The pressure chambers (25a, 25b) are, moreover, connected via in each case a plurality of exhaust tubes (34a, 34b) to exhaust volumes (30a, 30b) and to one of them also via a pressure relief valve (37). The pinch pressure produced between the consumable rings (32a, 32b) during formation of an arc (17) leads to a pressure buildup in the pressure chambers (25a, 25b) which contributes via the return channels (28a, 28b) to building up in the heating volume (18) a high blowout pressure which on the occasion of the next zero crossing causes a strong gas flow through the blowout slot (19) into the arcing chamber (16), which quenches the arc (17).