Puffer type gas circuit breaker

摘要

A puffer type gas circuit breaker wherein an insulated nozzle 2 made of heat proof resin and movable arc contact 3 are mounted on a puffer cylinder 4 to perform an open/close operation of the contact. In this circuit breaker, the insulated nozzle 2 is divided into three areas; a downstream area 2a, an area in the vicinity of the throat 2b and an upstream area 2c. The downstream area 2a and upstream area 2c are made of heat proof resin alone, while the area in the vicinity of the throat 2b is formed of heat proof resin mixed with inorganic material such as boron nitride. A movable arc contact cover 9 made of heat proof resin having two areas-a downstream area 9a and upstream area 9b-is provided between insulated nozzle 2 and movable arc contact 3, and only the downstream area 9a is made of heat proof resin mixed with inorganic material.