| 摘要 |
There is described a novel arc extinction method for use in switchgear, and improved, low cost power switchgear incorporating the novel arc quenching method. By physically severing the arc and the substantially simultaneous interposition of a high dielectric strength insulating barrier between the fixed contact and the moving contact, substantially consistent and predictable arc extinguishing characteristics are obtained. When the dielectric strength of the barrier exceeds the applied voltage, the arc cannot maintain itself nor can it reignite. Upon detection of a fault, moving contact 16 disengages from fixed contact 12 and retreats 28 from contact 12 creating arc 30. Insulating guillotine 24, in intimate sliding contact with the surface of insulating partition 18 moves 26 toward aperture 20 in partition 18. When edge 31 of guillotine 24 reaches aperture edge 33 of partition 18, arc 30 is severed and extinguished. The covering of aperture 20 by guillotine 24 insulates and isolates fixed contact 12 from moving contact 16 thereby substantially eliminating reignition of the arc. Partition 18 and guillotine 24 may be of high dielectric strength Teflon which withstands the direct action of intense arcs, is superior to ceramics in switchgear and has a low coefficient of sliding friction for the mating surfaces of guillotine 24 and partition 18.
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