Abstract: An electric motor for driving a circuit breaker operating handle is connected to the latter by two sets of linkages. The first set of linkages includes a drive arm and a driven arm mounted on fixed spaced centers and interconnected by a cam means. The drive arm is pivoted by connection to the drive motor through gearing and a slip clutch, and mounts a roller entered into a cam slot formed in the driven arm. The second set of linkages consists of a drive link and a main link also mounted on fixed spaced centers with the main link having means for engaging and moving a circuit breaker operating handle. The drive and main links are connected by a roller-slot arrangement, with the roller being positively guided along an arcuate path formed about a center remote from the centers of the links and arms. Positive guidance of this connecting roller causes the effective lengths of the links to change in accordance with different positions of the circuit breaker handle.

Abstract: A baffle assembly covering a vent opening in a molded case circuit breaker housing is constructed of two identical platelike elements having integral face protrusions. These elements are stacked in face-to-face relationship with their protrusions in engagement to maintain a narrow space between the element faces. Edge notches are provided to orient the elements so that the perforations of one element are misaligned with respect to the perforations of the other element so that arcing gases do not flow in a straight path through the baffle assembly.