BigPatents India

The heavy-duty circuit breaker can be filled with a quenching gas and contains a first moveable arcing contact piece (1) and a second moveable arcing contact piece (2) as well as a drive for driving the first arcing contact piece (1) and an auxiliary drive (3) for driving the second arcing contact piece (2). An arc (4) may burn between the arcing contact pieces. The heavy-duty circuit breaker has a heating chamber (11) for temporarily storing quenching gas heated by the arc (4) and an insulating nozzle (5), which has a throat (6) for guiding a quenching gas flow, which throat is connected to the heating chamber (11) by means of a channel (7). The throat (6) can be blocked at least partially by one of the two arcing contact pieces (2) , which is referred to as the blocking contact piece. The auxiliary drive (3) is designed such that, during an opening operation, a movement direction reversal of the second arcing contact piece (2) from a movement in opposite directions to a movement in the same direction of the two arcing contact pieces (1, 2) takes place, if the throat (6) is no longer at least partially blocked by the blocking contact piece (2). Advantageously, the gear is a gear (3) which is driven by the drive, (Figure .1) (Figure 1)