Molded case circuit breaker with modular crossbar

摘要

A molded case circuit breaker has modular crossbar members which connect the contact arm carriers of a desired number of poles for opening and closing the separable contacts of all of the poles simultaneously by a single spring powered operating mechanism. The modular crossbar members comprise shaft sections which engage openings in the contact arm carriers of adjacent poles. Bearings support the shaft sections and mount the contact arm carriers for rotation about a common pivot axis. In a preferred embodiment of the invention, the modular crossbar member is a single continuous metal shaft overmolded with an electrically insulative resin which also forms the bearing. Alternatively, separate metal shaft sections seat in sockets on either side of the molded bearing. In both instances, the shaft sections are keyed to the openings in the contact arm carriers for transmission of torque. In the exemplary crossbars, the shaft sections are hexagonal in cross-section.