Abstract: A residential or commercial circuit breaker of the narrow case type, typically having a width of 3/4 inch or 1 inch, is provided with a combination slot motor and arc chute 102 mounted within the case 2 and around the current carrying conductors 8 and 12. The combination slot motor and arc chute 102 concentrates the current-induced magnetic repulsive force between the conductors 8 and 12 to boost contact separation force, and also extinguishes the arc. The slot motor portion 106, 108 of the combination structure 102 continues to support the magnetic force which tends to force the arc into the arc chute portion 104 away from the contacts 10, 16 and operating mechanism. The combination slot motor and arc chute 102 is particularly simple and inexpensive, yet very effective within the size constraints of the narrow type breaker case 2.

Abstract: A residential or commercial circuit breaker of the narrow case type, typically having a width of 3/4 inch or 1 inch, is provided with a single-piece nonlaminated slot motor 102 mounted within the case 2 and around current carrying conductors 8 and 12 for concentrating magnetic repulsive force and boosting contact separation force. A dramatic increase in short circuit interruption capacity is achieved, at minimal cost.

Abstract: A high speed electromagnetically actuated electromechanical switch is provided by a bistable electric snap blade operated by an electromagnetic actuator. A magnetically permeable yoke directs the flux paths of a pair of coaxial coils. An armature plunger shuttles axially reciprocally in the coils between first and second positions. The snap blade has a pair of cantilever arms extending towards each other to engage the armature plunger in the gap therebetween for lateral flexing actuation. Energization of a given coil provides a primary flux path around that coil through the yoke and the armature plunger, and provides a secondary flux path around both coils through the yoke and the armature plunger. The primary flux path force around either coil is always stronger than the secondary path.

Abstract: A thermally responsive shape memory effect (SME) element (4) is positioned adjacent a fixed heater (40) for moving away from the heater to a switch actuating "memory" position as current induced temperature increases, thereby establishing changes in heat transfer coefficient between the heater (40) and thermally responsive element (4) for each increment of movement. An intermediate switch actuating lever (22) is carried on a movable range adjustment lever (16) to vary pretravel of an SME driven plunger (12). The SME element is resettable against a fixed stop (2c) for achieving accurate repetitive resetting of the device.

Abstract: An electromagnetic actuator is provided by an armature plunger which reciprocally shuttles between magnetic paths having common overlapping portions through the plunger. A magnetically permeable yoke directs the flux paths of a pair of coaxial coils. When either coil is energized, a first flux path is created around that coil through the plunger and a second flux path is created around both coils through the plunger. The first path pulls the plunger to close an axial magnetic air gap. The second path holds the plunger in place. The ratio of the permeances of the two paths is controlled such that one path always overpowers the other, to insure plunger movement in either direction.

Abstract: An electromagnetic actuator is provided by a single armature plunger that reciprocally shuttles between two magnetic paths provided by a pair of coils. Undesired retarding-flux is cancelled in overlapping linkage paths through the plunger, yielding increased net magnetic force in the intended direction of movement and faster plunger operation. When either coil is energized, a primary flux path is created around that coil through the plunger, and a secondary flux path is created around both coils through the plunger. The primary path attracts the plunger to close a magnetic air gap. The secondary path holds the plunger in place. Current to the ON coil is also supplied through a limiting resistor to the OFF coil to generate reverse polarity flux in the latter cancelling secondary flux from the ON coil.

Abstract: A magnetic snap latch having a coil (4) wound on a preformed insulating bobbin (3) having anti-rotation projections (3a) that locate and fix the coil within a high permeability magnetic shell (2). A high permeability magnetic plunger (1) extends through a hole (2a) in the shell into the coil (4) and has rigidly secured thereto a low permeability magnetic disk (6) within the shell. A high permeability backplate (5) closes the open end of the shell and defines an air gap (AG2) in which is located a non-magnetic return spring (7). When the coil is energized, the disk (6) is initially attracted to the shell (2) to move the plunger (1) a small distance to the right but the disk (6) then saturates and the increasing magnetic force in the air gap (AG2) snaps the plunger (1) to the left, whereafter the return spring (7) restores the plunger (1) when the coil (4) is deenergized.

Abstract: A pushbutton circuit breaker switch, including two sets of contacts, connected in series. One set of contacts, the switch contacts (24, 30), open and close during normal on-off switch cycling. The other set of contacts, the breaker contacts (36, 42, 54), open only on overload, leaving the switch contacts closed. Of the three breaker contacts, two are stationary (36, 42) and one is a movable bridging contact (54). This movable contact is mounted on an insulative slide block (44), and an overload slides into an insulative enclosure (10g) in the housing (10) of the switch. Thus the movable contact is almost completely surrounded by insulative material cutting off any arc formed. The switch contacts are opened and closed by a W-cam (16). The actuator for the W-cam is a trapeze spring (14), the length of the horizontal portion of which is greater than the width of the W-cam, so that the center high point (16a) of the W-cam passes through the actuator without interference therewith.

Abstract: A two-bimetal thermostat provides double motion for enhanced contact actuation and minimum differential. Two bimetal plates are pivotally supported at one end to extend generally parallel. The other, deflectable ends of these bimetal plates, one of which is shorter than the other, have right-angle bends and are biased by a compression C-spring for overcenter snap-action. These deflectable ends are coupled by drive pins to respective contacts of a spring-biased contact pair to be free of the bimetal plates when closed and are actuated thereby to open condition. Differential adjustment is accomplished by adjusting one bimetal plate longitudinally to vary the C-spring load thereby to correspondingly vary the temperature differential between contact closure and opening. Range adjustment is attained by turning a knob which acts through a cam on the pivotal mounts to vary the angle between the bimetal plates thereby to require more or less bimetal bending for contact actuation.

Abstract: A toggle switch having a molded insulating frame mounting a snap-in bushing secured thereto for snap-in mounting of the switch in a hole in a mounting pane. This bushing pivotally retains the toggle lever for operating the switch contacts within the base. This frame includes a pair of depending legs between which the insulating switch base is snap-in mounted and retained. This frame has integrally molded therewith a pair of oppositely disposed resilient back-up elements for pressing against the back of the panel, these elements having at their ends ramped riser bars for accommodating a range of different panel thicknesses while retaining the switch against significant movement on the panel during toggle lever operation.

Abstract: A toggle switch having a molded insulating frame including a pair of depending legs between which the insulating switch base is snap-in mounted and retained. The frame includes a bushing having a resilient collar for snap-in mounting of the switch in a hole in a mounting panel. This bushing pivotally retains the toggle lever for operating the switch contacts within the base. The legs of the frame are inwardly curved and tapered so that bases of varying tolerances may be retained thereby rigidly and securely.

Abstract: A tool for removing a snap-in bushing type toggle switch or the like from a hole in a mounting panel. The tool is molded of plastic material and is provided with a spring-biased self-opening slidable chuck snap-in assembled within a compressor tube and is adapted to squeeze the snap-in collar or skirt of the snap-in bushing so that it becomes released from the mounting panel. The outer compressor tube having a mushroom handle at one end is adapted to slide forwardly over the chuck to compress or squeeze it and the snap-in collar therewithin. A spring-biased ejector pin slidable within the chuck is depressed by the toggle lever of the switch and is loaded by its spring compressed by the compressor tube and serves to snap the switch from the panel hole upon release of the snap-in collar.A first version has an integrally-molded resilient lug on the chuck that snaps out into an elongated slot in the compressor tube wall to snap-in assemble the chuck within the compressor tube for limited sliding movement.

Abstract: A tool for removing a snap-in bushing type toggle switch from a hole in a mounting panel. The tool is made of metal or plastic and is provided with a spring-biased self-opening chuck and compressor tube adapted to squeeze the snap-in collar or skirt of the snap-in bushing so that it can be pushed back through the hole in the panel for removal. An outer, compressor tube having a mushroom handle at one end is adapted to slide forwardly over the chuck to compress or squeeze it and the snap-in collar therewithin. A spring-biased ejector pin within the chuck is depressed by the toggle lever and serves to snap the switch out upon release of the snap-in collar. The tool is used by placing the chuck over the snap-in bushing against the panel and pressing on the mushroom handle to slide the compressor tube over the chuck against the panel whereupon the ejector pin kicks the switch out behind the panel.A simpler version includes only a chuck and a manually slidable compressor ring, both molded of plastic material.