Bi-directional direct current switching apparatus having arc

Abstract

Direct current switching apparatus having two arc extinguishing chambers located in a common transverse plane, one chamber being divided into separate laterally spaced portions disposed below the other chamber, a pair of spaced conductors each having a contact element and an arc runner extending from near the contact, the arc runners being curved and disposed in a convex mirror-imate relationship to each other between the laterally spaced portions, distal ends of each arc runners providing a divergent path into the other chamber, a conductor disposed at outboard sides of the laterally spaced arc chamber portions cooperating with concave sides of the arc runners to provide divergent paths into the spaced arc chamber portions, power supply terminals connected to the respective spaced conductors, magnetic plates disposed in front and in back of the arc chambers having portions providing a magnetic path externally around the chambers, permanent magnets magnetically coupled to at least one of the magnetic plates providing a magnetic field in the plates and across the arc chambers in a forward direction, a movable contact movable normal to the forward direction into and out of bridging engagement with the stationary contact elements, and an electromagnetic drive motor disposed coextensive with the arc extinguishing chambers, coupled at a lower end to the movable contact. Arcs established between the stationary and movable contact elements are moved from the contacts into either arc extinguishing chamber by the magnetic field coacting with current in the arc to generate forces which move the arc.