Bi-directional direct current switching apparatus having bifurcated arc

Abstract

Direct current switching apparatus having front and rear arc extinguishing chambers substantially coextensive, the rear chamber being separated into two laterally spaced arc extinguishing chambers, each arc extinguishing chamber comprising rows of non-magnetic parallel splitter plates, a pair of spaced conductors each having a stationary contact element spanning both the front and rear arc extinguishing chambers, power supply terminals connected to the respective spaced conductors, magnetic plates disposed in front of the front chamber and in back of the back chamber having magnetic means providing a magnetic path externally around the chambers, permanent magnets magnetically coupled to at least one of the magnetic plates providing a magnetic field across the respective chambers, a movable contact movable normal to a front to rear direction into and out of bridging engagement with the stationary contacts, and an electromagnetic drive motor disposed coextensive with said arc extinguishing chambers coupled at a lower end to the movable contact. Bifurcated arc runners of the conductors lead from the stationary contact elements into respective front and rear chambers, and a conductor surrounds the laterally spaced arc extinguishing chambers to cooperate with the respective arc runners therein. Arcs established between the stationary and movable contact elements are moved from the contacts into either the front or rear chambers by the magneteic field according to polarity of the power applied to the respective terminals. The electromagnetic motor is readily and inexpensively manufacatured and assembled by utilizing molded housing parts to position and retain elements of the motor. The apparatus is particularly well suited for high voltage, high current applications requiring lightweight, compact apparatus.