Patent ID: 8274007

Claim:
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; an actuator operable for moving the first or second contact in an axial direction through the opening stroke to open the electric power circuit; the contacts configured to form an arc extending generally in the axial direction across an arc gap between the contacts during the opening stroke, the arc cause by an electric current conducting across the contacts; a first permanent magnet having a first pole having a first polarity and a second pole having a second polarity carried by the first contact, the first and second poles spaced apart from each other in a radial plane perpendicular to the axial direction; wherein the permanent magnet is generally ring shaped and disposed in the radial plane to generate a magnetic field that imparts a tangential force on the arc in the radial plane to cause the arc to rotate along a generally circular path about the axial direction; wherein the magnetic field created by the magnet is unaffected by the electric current conducting across the contacts; and wherein rotation of the arc through the dielectric gas facilitates extinguishing the arc without use of a device to direct a stream of dielectric gas into the arc gap.