Puffer-type gas circuit breaker.

摘要

A puffer-type gas circuit breaker includes arc extinguishing gas filled in the interior of the gas circuit breaker; a fixed contact (1); a movable contact (2) disposed in opposed relation to the fixed contact (1) so as to come into contact therewith; a fixed piston (12); a drive shaft (11) slidably extending through the fixed piston (12), and driving the movable contact (2) toward and away from the fixed contact (1); a puffer cylinder (13) slidably fitted on the fixed piston (12), the puffer cylinder (13) cooperating with the fixed piston (12) to define a puffer chamber (7) within the puffer cylinder (13); an outer cylinder (15) mounted on an outer periphery of the puffer cylinder (13) to form a thermal puffer chamber (8) outside the puffer cylinder (13); a cover (19) covering an outer surface of the movable contact (2); a first insulating nozzle (5) surrounding the cover (19) to form a first gas flow passage (18a) for guiding the arc extinguishing gas from the puffer chamber (7) to an arc generating portion; and a second insulating nozzle (6) surrounding the first insulating nozzle (5) to form a second gas flow passage (18b) for guiding the arc extinguishing gas from the thermal puffer chamber (8) to the arc generating portion. <IMAGE>