Electric switch

摘要

A circuit breaker having a crank (12) for coupling a switching mechanism to the contact pole structure (15) is presented. The crank (12) has a pair of cam surfaces (12U, 12L) which cooperate with a blocking lever (14) to restrict movement of the operating handle (20) when the contacts of the circuit breaker are welded. The blocking lever (14) is arranged such that it does not interfere with the handle (20) under normal operating conditions.