Circuit breaker trip unit employing a rotary plunger

摘要

A circuit breaker trip unit includes a housing and a rotary plunger pivotally mounted within the housing. The rotary plunger has an on position and a tripped position. A portion of the rotary plunger is pivoted outside of the housing in the tripped position. A trip bar is pivotally mounted within the housing and includes a first tab latching the rotary plunger in the first position and releasing the rotary plunger from the first position. The trip bar also includes a second tab. A trip actuator includes a solenoid and a rotary trip lever engaging the second tab of the trip bar, in order to pivot the trip bar and release the rotary plunger from the on position. A spring biases the trip bar, in order that the first tab latches the rotary plunger in the on position. A pair of springs biases the rotary plunger to the tripped position.