Angular stepped U-core and armature plate system generating increased magnetic force for trip mechanism of circuit breaker

A circuit breaker, the circuit breaker comprising:

• a plurality of pole assemblies, each pole assembly comprising:
• a line conductor and load conductor structured to provide an electrical connection between a corresponding load and a power source;
• a stationary conductor;
• a movable conductor, the movable conductor being structured to be actuated between a closed state and an open state relative to the stationary conductor in order to respectively close and open the electrical connection between the line conductor and the load conductor;
• and
• a trip mechanism structured to be actuated when current through the load conductor exceeds a predetermined threshold, the trip mechanism comprising:
• a magnetizable U-core coupled to the load conductor, the U-core being a U-shaped core;
• an armature structured to be actuated by the U-core;
• and
• a lever arm coupled at one end to the armature;
• and
• an operating mechanism, the operating mechanism being aligned with exactly one of the pole assemblies and being operably coupled to the movable conductor of every pole assembly;
• wherein, with respect to the one pole assembly with which the operating mechanism is aligned, the lever arm of the one pole assembly is positioned to engage the operating mechanism when current through all of the pole assemblies is within the current rating of the circuit breaker;
• wherein each trip mechanism is operably coupled to every other trip mechanism in the circuit breaker,
• wherein, for each trip mechanism:
• the U-core comprises a base and two arms extending from the base, the base extending between the two arms in a width dimension and the two arms extending from the base in a height dimension orthogonal to the width dimension,
• each arm of the U-core comprises a thick portion having a major width and a thin portion having a minor width, the major width spanning a greater distance in the width dimension than the minor width, the thick portion extending from the base to the thin portion, the thin portion extending from the thick portion away from the base,
• for each arm of the U-core, a step is formed at an interface of the thick portion and the thin portion,
• the trip mechanism is structured such that, when current through all pole assemblies is within the current rating of the circuit breaker, the armature is spaced apart from the steps of the U-core and positioned between the thin portions of the U-core relative to the width dimension, and
• the trip mechanism is structured such that, when current through the corresponding pole assembly reaches a fault level threshold, the U-core gets energized and pulls the armature between the thin portions of the U-core toward the steps of the U-core, such that the lever arm of the corresponding pole assembly and the lever arm of every other pole assembly gets rotated to an actuated position,
• wherein, with respect to the one pole assembly with which the operating mechanism is aligned, the lever arm of the one pole assembly is configured to disengage from the operating mechanism when the lever arm of the one pole assembly gets rotated to the actuated position, and
• wherein the operating mechanism is configured to actuate all of the movable conductors to their open state when the operating mechanism is disengaged from the lever arm of the one pole assembly.