ROLLER LATCHING AND RELEASE MECHANISM FOR ELECTRICAL SWITCHING APPARATUS

摘要

A circuit breaker includes a housing; separable contacts moveable betwe en closed and open positions; an operating mechanism, for moving the separable contacts between the closed and open positions, having a first latched position and a second unlatched position corresponding to the open position of the separable contacts, and including a pair of cradles pivotally supported about a pivot axis within th e housing to pivot in a first pivotal direction to the first position of the operating mechanism and a second pivotal direction to the second position of the operating mechanism; a handle mechanism for moving the cradles in the first pivotal direction; a latch mechanism for latching the operating mechanism in the first position thereof and for releasing the operating mechanism to the second position thereof, including a latch plate pivotally supported within the housing having two opposing elongated openings, a rolle r pin cross member generally parallel to the cradle pivot axis supported by the latch plate at each of the openings, and a spring mechanism for biasing the cross member with respe ct to the cradles; and a trip mechanism cooperating with the latch mechanism for releasing the operating mechanism to the second position thereof. An arcuate reset surface of the cradles independently engages a corresponding end of the cross member when t he operating mechanism is moved toward the first position thereof. The cross member engages a linear latch surface of the cradles for latching the operating mechanism in the first position thereof.