Abstract: A circuit breaker having a switch mechanism consisting basically of a pivotally mounted latch which is releasably mounted on a release member and which carries a pivotally mounted contact, and of a pivotally mounted manually operable element for operating the circuit breaker. A spring is connected to the manually operable element at a position offset with respect to the pivotal axis of the element and is arranged to apply a force to the pivotable latch at a position close to the pivotal axis of the latch. A latch lever interconnects the manually operable element and the pivotable latch and is connected to the manually operable element eccentrically with respect to the pivotal axis of the latter and is connected to the pivotable latch in a manner as to form the pivotal axis of the latter.