Circuit interrupter with improved trap for removing particles from fluid insulating material

Claim 1

Apparatus for establishing and extinguishing an electric arc and actuating means therefor, comprising first and second spaced electrodes, means for energizing said electrodes, said electrodes being adapted to be energized at different electrical potentials, said first electrode comprising a curved hollow tubular cylindrical conductor disposed about a similarly curved longitudinal axis, said second electrode comprising an electrical conductor having a generally circular cross section, said second electrode having the shape of an arcuate portion disposed generally concentrically within said first hollow electrode, said electrical potential of said second electrode being periodically relatively higher than the electrical potential of said first electrode when said second electrode is energized, sulfur hexafluoride insulating fluid disposed around said second electrode conductor and contained within said first hollow tubular cylindrical electrode, an electrical field at least periodically existing between said first and second electrodes when at least one of said electrodes is energized, a curved hollow cylindrical electrically insulating member disposed radially between said first and second electrodes, said electrical insulating member comprising an inner surface, said inner surface having an inner periphery and bottom part, said inner surface having undulating protrusions, formed along its length said protrusions being disposed longitudinally on said insulating member in the same general direction as said longitudinal axis, said protrusions being disposed over at least a portion of said bottom part of the periphery of said inner surface, insulating supporting means for supporting said electrically insulating member within said first electrode, said electrically insulating member comprising material of high electrical permittivity, said electric field being refracted by said high permittivity dielectric material comprising said undulating protrusions so as to weaken said electric field in the regions between said protrusions so that electrically charged particles in said sulfur hexafluoride insulating fluid upon entering the regions between said protrusions are generally immobilized due to the weakened electric field within those regions, said apparatus for establishing and extinguishing said arc being actuated by said actuating means.