High-speed high-current circuit interrupter having electrodynamically operated arcing contacts

Claim 1

A high-current circuit interrupter comprising: an electrical main circuit; an electrical auxiliary circuit connected in parallel with said main circuit and having a higher electric resistance than said main circuit; separable main contact means inserted in said main circuit and having a movable main contact member; separable arcing contact means inserted in said auxiliary circuit and having a movable arcing contact member in driving connection with said movable main contact member; elastic means urging said movable contact members resiliently towards the closed-circuit position thereof; impetus means having a trigger member adapted to mechanically operate said movable main contact member strikingly at the appearance of a short-circuit current flowing through said circuit interrupter to separate said main contact means against the action of said elastic means and transfer said current to said auxiliary circuit; said auxiliary circuit comprising first electrodynamic means, said first electrodynamic means tending to keep said arcing contact means in the closed-circuit position thereof under the action of said current; and second electrodynamic means urging said arcing contact means towards the open-circuit position thereof under the action of said current; said first and second electrodynamic means being adapted to cause said arcing contacts to remain in the closed-circuit position thereof a short lapse of time after the transfer of said current to said auxiliary circuit and to sequentially separate, thereby to draw an arc therebetween.