Abstract: A device for supporting semi-rigid workpieces to be embroidered. Hoop ties are mounted to a hoop frame to provide a support surface for one side of the workpiece, while a backbone further comprising at least two knurled fingers provide a frictional supporting surface for an opposing side of the workpiece. Rubber tubing can be stretched around the hoop ties for easily mounting each of the ties to the hoop frame, and which provides another frictional supporting surface that is less abrasive than the knurled hoop fingers. The angle and the height of the backbone can be adjusted to accommodate workpieces of varying rigidity and thickness.

Abstract: Electrical switching apparatus such as a power circuit breaker, network protector or switch has a self-supporting operating mechanism module including a cage formed by a pair of side plates rigidly clamped in spaced relation by spacers. The cage supports all of the operating mechanism components including a helical compression close spring mounted fully between the side plates and coupled to a cam member through a rocker in a manner which maintains the forces longitudinal to the spring. The cam member has a charging cam with a charge profile for compressing the close spring and a close profile through which the spring drives the cam member to effect a controlled release of stored energy to close the contacts of the apparatus. A close prop, spring biased to an unlatched position, is latched to secure the close spring in the charged state by a latch assembly reset by a reset lever separate from the close prop which in turn is reset by rotation of the cam member during charging.

Abstract: Two molded case electrical switches such as circuit breakers, network protectors, disconnect switches and transfer switches, are secured together side-by-side by joining blocks having tongues extending along their sidewalls which engage undercutting grooves undercutting the irregular surfaces of the confronting sidewalls of the switch molded casings with an interference fit. Separate joining blocks for the front and rear sections of the molded casing are driven into place and retained by bolts engaging flanges on the molded casing. The poles are paralleled by external conductors in any desired configuration so that the standard switches can be used without customization.

Abstract: A circuit breaker with trip indicator assembly for indicating the trip status of the circuit breaker. The trip indicator assembly includes a spring powered shaft movable between a cocked position and a trip position in which the spring powered shaft protrudes through the housing of the circuit breaker to indicate the trip status. The shaft is operatively connected to a trip actuating mechanism of the circuit breaker so as to actuate the shaft in response to the trip actuating mechanism actuating an operating mechanism of the circuit breaker. A lost motion coupling is provided to assure that the trip indicator assembly is not actuated until after actuation of the operating mechanism. A bell alarm switch assembly for signalling the trip status of the circuit breaker may be operatively connected to the trip indicator assembly.

Abstract: An actuator assembly for an electrical power switch apparatus, the actuator assembly having a housing and a plunger positioned within the housing where the plunger is movable between a set position and an actuated position. The plunger includes a compression spring to provide a pre-load thereto that biases the plunger away from the set position and toward the actuated position. A magnet contained in the housing and positioned proximate to the plunger establishes a magnetic force which overcomes the pre-load of the compression spring and maintains the plunger in a set position. A coil assembly, that when energized, produces an electromagnetic force which bucks the magnetic force established by the magnet allowing the plunger to be propelled by the compression spring to the actuated position. A screw extends through an opening in the plunger for engagement with the compression spring so that rotation of the screw results in the adjustment or calibration of the pre-load of the compression spring.

Abstract: An improved trip device for operating a trip mechanism which, in turn, operates a circuit breaker mechanism for opening a set of electrical contacts. The trip device includes a spring-biased actuating rod which is mechanically operated by a solenoid. The actuating rod has a notched end which is secured by a rotatable shaft at a notch portion of the shaft. The shaft has latch arms, and the core of the solenoid has projections extending into slots in the latch arms. When the solenoid receives a faulty current signal, the core moves and causes the projections to forcibly impact against the latch arms which rotates the shaft, whereby the notch portion of the shaft aligns with the notched end of the actuating rod and the actuating rod reciprocally moves into the notched portion of the shaft thereby actuating the trip mechanism.

Abstract: A modular trip unit for automatically tripping a switch of a circuit breaker when the circuit breaker is being removed from its panel mounting when the circuit breaker has not been manually overridden. The modular trip unit is an integral part of the circuit breaker and includes a trip interlock assembly integrally mounted in the modular trip unit. The trip interlock assembly comprises a spring biased slider extending through and out of the housing of the trip unit, and an actuator in engagement with the slider. The actuator engages a first cam surface of a trip bar and a catching member of a latching assembly is engaged by a lip member on a second cam surface of the trip bar. When the circuit breaker is being mounted on the panel mounting, the slider is forced inwardly thereby compressing a spring associated with the slider, and the slider causes the actuator to rotate in a first direction.