Abstract: A fastenerless electromagnetic trip assembly employs minimal parts for effecting the release of a set of circuit breaker contacts. The parts include an armature, an armature bias spring, a yoke and a trip bar, all of which may be retractably supported in associated compartments within the circuit breaker housing. The yoke provides an electromagnetic field in response to electric current flowing in the circuit breaker. A spring biases the armature until the electromagnetic field reaches a predetermined strength, at which point the bias is overcome, and the armature strikes the trip bar and is drawn toward the yoke, thereby causing the trip member to actuate the release of the circuit breaker contacts.

Abstract: A flush mounted indicating button assembly and operating button assembly each connected to a cover having a pair of holes which receive identical buttons of the assemblies. Each button includes a circular head portion having a flat top surface and a circular base portion having a lesser diameter than the head portion which has a flat bottom surface and defines a collar portion at the bottom of the head portion. The base portion of each bottom is provided with a circumferential channel adjacent the bottom surface which carries a retaining ring. The indicator button is positioned within the hole by a leaf spring member which is connected to the bottom surface of the cover and includes an opening shaped and dimensioned to permit passage of the base portion while preventing passage of the head portion of the button. The opening is in registration with the hole in the cover and a helical coil encircles the base portion intermediate the leaf spring member and the retaining ring.

Abstract: An automatic electric side-by-side two-pole circuit breaker having an insulating casing formed from the complementary association of a base casing, an intermediate casing and a cover which provide a pair of mechanism receiving compartments in side-by-side association. Each compartment carries a pivotally supported operating handle which extends partially outward from the casing for external manual operation, a line terminal, a load terminal electrically connected to said line terminal, a stationary contact intermediate said line terminal and said load terminal and a movable blade which carries a movable contact on one end and has its opposite end connected to the handle. A releasably latched generally thin trip lever is pivotally mounted within the compartment and is releasable from its latched position to a tripped position to effect separation of the contacts. The trip lever includes an upstanding leg which is engaged by a protuberance on the handle for resetting the trip lever.

Abstract: The following specification describes a circuit breaker having a handle pivoted about an axis transverse to the axis of blade rotation for controlling an operating assembly to pivot a cam about an axis parallel to the blade axis to open or close the breaker contacts. The operating assembly is located in the center compartment of the breaker while the contacts and blades are located in end compartments of the breaker, and when the blades are moved past a predetermined position, they are then independently moved by a respective snap acting spring. Sensing means control the operating assembly in the event of a fault current to move to a trip position and open the contacts while providing a visual signal of the trip condition. Arc gases are vented to prevent engagement with the copper conductor connected to each contact and a stainless steel blade bracket is interposed between the movable contact and the copper blade to prevent an arc from contacting the copper blade.