Patent ID: 8853586

Claim:
An electrical switching apparatus comprising: a first arc runner; a second arc runner; a first contact in electrical communication with said first arc runner; a second contact in electrical communication with said second arc runner; a movable contact comprising a first portion and a second portion respectively cooperating with said first contact and said second contact to provide a closed contact position in which said movable contact electrically engages said first and second contacts, and an open contact position in which said movable contact is disengaged from said first and second contacts; a first arc chamber comprising a first end, an opposite second end, a longitudinal axis therebetween, and a plurality of first arc plates between the first end and the opposite second end, one of the first arc plates at the first end of the first arc chamber being proximate said first arc runner, another one of the first arc plates at the opposite second end of the first arc chamber being proximate the first portion of said movable contact as said movable contact moves from the closed contact position toward the open contact position; a second arc chamber comprising a first end, an opposite second end, a longitudinal axis therebetween, and a plurality of second arc plates between the first end and the opposite second end of the second arc chamber, one of the second arc plates at the first end of the second arc chamber being proximate said second arc runner, another one of the second arc plates at the opposite second end of the second arc chamber being proximate the second portion of said movable contact as said movable contact moves from the closed contact position toward the open contact position; an operating mechanism cooperating with said movable contact to move said movable contact between the closed contact position and the open contact position; and a magnet assembly cooperating with said first and second arc chambers to establish a generally unidirectional magnetic field normal to the longitudinal axes of said first and second arc chambers, normal to a first direction of a first arc between the first contact and the first portion of the movable contact as said movable contact moves away from the closed contact position toward the open contact position, and normal to an opposite second direction of a second arc between the second contact and the second portion of the movable contact as said movable contact moves away from the closed contact position toward the open contact position, in order that said generally unidirectional magnetic field causes one of the first arc and the second arc to enter one of said first and second arc chambers, respectively, depending upon a direction of current flow between the first contact and the second contact.