Patent ID: 8063333
Filing Date: 2011-11-22
Classification: H01H

Abstract:
1. A circuit interrupter configured to be electrically connected in an electric power circuit; comprising: a sealed chamber containing a dielectric gas; a contactor located within the chamber having first and second contacts movable in relation to each other during an opening stroke from a closed position in which the contacts are configured to be electrically connected to close the electric power circuit to an open position in which the contacts are configured to be electrically separated to open the electric power circuit; a drive mechanism operable for moving the contacts through the opening stroke and creating a flow of the dielectric gas within the chamber to open the electric power circuit; the contacts configured to form an arc extending in an arc gap direction across an arc gap between the contacts during the opening stroke; a nozzle configured to direct the flow of the dielectric gas into the arc gap to extinguish the arc during the opening stroke, the nozzle comprising an arc extending zone in fluid communication with an arc extinguishing zone; a dielectric gas regulator operable for restricting the flow of the dielectric gas into the arc gap during a first portion of the opening stroke to cause the arc gap to extend across the arc extending zone; the dielectric gas regulator further operable for unrestricting the flow of the dielectric gas into the arc gap during a second portion of the opening stroke to initially extinguish the arc after the arc has extended across the arc extending zone and into the arc extinguishing zone; and the arc extending zone having a sufficient length in the arc gap direction to prevent the arc from flashing over across the arc gap between the contacts after the arc has been initially extinguished.