Abstract: An opening assist mechanism is for the cradle assembly of a circuit breaker including a housing enclosing separable contacts, and an operating mechanism for opening and closing the separable contacts. The operating mechanism includes a trip bar and a cradle assembly. The cradle assembly includes a first toggle link, a second toggle link pivotally coupled to the first toggle link by a first pivot, and a cradle member pivotally coupled to the second toggle link by a second pivot. The cradle member includes a third pivot and a latching portion structured to engage the trip bar when the cradle assembly is disposed in a position corresponding to the separable contacts being closed or otherwise closeable. The opening assist mechanism comprises an actuator, such as a kicker pin, disposed on the cradle member and structured to engage and move at least one of the first and second toggle links in response to an actuation of the operating mechanism.

Abstract: A circuit breaker including a housing, separable contacts, a cradle rotatably mounted within the housing, an alarm switch mounted within the housing, and an interface lever disposed between the cradle and the alarm switch. The cradle is adapted to rotate about a first axis in a first direction when the circuit breaker moves to a tripped position in which the separable contacts are separated from one another. The alarm switch includes an actuation lever movable in an actuation direction, wherein movement of the actuation lever in the actuation direction causes the alarm switch to activate an alarm device electrically connected thereto. When the cradle rotates in the first direction, the cradle exerts a first force against the interface lever that causes the interface lever to exert a second force against the actuation lever that causes the actuation lever to move in the actuation direction.

Abstract: A circuit breaker includes a housing including a primary cover and a secondary cover having a tab; separable contacts; and an operating mechanism adapted to open and close the separable contacts. The operating mechanism includes a cradle pivotally mounted within the housing, the cradle including a latch, and a latch mechanism within the housing. The latch mechanism is adapted to capture the latch of the cradle when the separable contacts are closed. The operating mechanism also includes a rotary interlock pivotally mounted within the housing and cooperating with the latch mechanism and the tab of the secondary cover to release the latch of the cradle and to trip open the separable contacts when the secondary cover is removed from the primary cover.

Abstract: A support structure for a circuit interrupter latch member includes a first side plate having a first opening, and a second side plate having a second opening. A first hardened bushing includes a first opening and a first perimeter. The first opening of the first hardened bushing is adapted to pivotally mount a first tab of the latch member. The first perimeter is coupled to the first side plate at the first opening thereof. A second hardened bushing includes a second opening and a second perimeter. The second opening of the second hardened bushing is adapted to pivotally mount a second tab of the latch member. The second perimeter is coupled to the second side plate at the second opening thereof. The hardened material of the first and second side plates is harder than the unhardened material of the first and second side plates.