Gas-blast switch

Abstract

A gas-blast switch has a housing which encloses an arcing chamber, an accumulator space and an expansion space. Two relatively moveable contact members are arranged in the housing. One of the contact members moves through a nozzle. The nozzle is formed of and defined by two moveable nozzle parts, the relative position of which determines the size of a discharge cross-section in the nozzle. During a switching-off operation, the moveable contact member moves out of the arcing chamber and quenching gas flows from the accumulator space into the expansion space, through the arcing chamber, i.e. the nozzle. The size of discharge cross-section of the nozzle varies through movement of the nozzle parts which respond to pressure created in the switch, without the assistance of elaborate compression springs. To this end, the nozzle parts are freely mounted to move in response to pressures generated in the switch and they are disposed in the gas path between the arcing chamber and the accumulator space.

Dependencies are inferred from the claim text.