GB773386A - Improvements in high-speed electrical disconnecting devices - Google Patents

Abstract

773,386. Automatic circuit breakers; arcrupturing in switches; actuation of switches EMAG ELEKTRIZITATS-GES. May 13, 1955 [May 22; 1954], No. 13902/55. Class 38(5) In a switch, a main current path 1, 4 is interrupted by a chemical energy source which also initiates the interruption of a parallel secondary current path 7, 8 in which final disconnection occurs by elongation of the arc produced therein. In Fig. 1 the main current path 1, 4 extends through an explosive conducting cartridge 5 and is broken on the firing of the cartridge. The detonation momentarily increases the contact pressure between a bridging contact 9 and contact members 7, 8, before a spring 16 moves the contact 9 down to open the parallel path. The arcs drawn between the contacts 7, 9, 8 unite and the resulting arc is blown along arc runners 10, 11 by magnetic blowout device 12, 13 and elongated by an insulating partition 17. In other arrangements the main current path is broken on the explosion of a charge fracturing a conductor (Fig. 2, not shown) or opening a bridging contact against the bias of a spring. In the latter case the bridging contact is latched in the open position (Fig. 3, not shown). The parallel secondary path may have two breaks with oppositely poled blow-out coils and be so arranged that only the break having the correctly polarized coil for the current to be interrupted is opened.