Abstract: A heating element terminal comprising a tubular conductor extending through the central bore of a two-piece insulating clamp member and an aligned aperture of the heating element frame clamped therebetween. The tubular conductor includes a flattened terminal plate at a first end projecting outwardly of the heating element and at the second opposite end includes a compression sleeve portion extending axially therefrom and projecting inwardly of the heating element. An end of the resistance wire of the heating coil is inserted into the central bore of the inwardly projecting compression sleeve portion which is crimped to secure the end of the resistance wire to the said second end of the terminal. The flattened plate formed at the first end of the terminal is drawn into abutment against the two-piece clamp member, and the second opposite end is similarly flattened at the point immediately adjacent the opposite side of the clamp member.

Abstract: An electrical stab assembly for connection to vertical bus bars in an electric control center and which includes connector jaws floatably mounted in an insulated molded base. The floatable mounting permits the connector jaws to move with the bus bars to which they are connected, as the bus bars move due to thermal expansion, thus eliminating relative motion between the bus bars and the jaws connected thereto which is one of the basic causes of failure of stab type connector jaws.

Abstract: A computer based control system having a protection circuit including a bistable circuit arranged to disable the outputs of the control system at the end of a scan period of the system. The bistable circuit is operated through logic gates arranged to monitor fault in the control system.

Abstract: A three part bus support for supporting a cylindrical tubular bus on an insulator comprises a base and two identical end portions. Each end portion has a hook portion defining an opening and a base portion which is connectible to either of the opposite ends of the base at one of two wall portions formed along opposed ends of the base. When the end portions are connected to the base, the openings defined by the hooks are aligned for receiving a tubular bus. A projection of one end of the base portion of each end portion is tangent to an inner surface of the hook portion where the bus exerts a force caused by wind, and the base is asymmetrical about a longitudinal axis passing through the opposite ends of the base to provide improved locations of fulcrums of lever arms of the wind forces.

Abstract: A weatherproof junction box cover assembly, comprising a structural member for mounting relationship with a junction box and a cover hingedly mounted on the structural member with cooperative inter-acting hood means at the top and sides of the cover assembly. A shiftable bias means is provided to normally bias the cover toward a closing position, the bias means being shiftable between an over-center station in relation to the pivot means whereby the cover will stay open when moved to the fully open position and a direct-closing-bias station whereby the cover will be constantly biased toward the closing position. The same cover assembly may therefore be used as a stay-open device or as a self-closing device, merely by shifting the anchor point of the bias means.

Abstract: A safety guard for a press brake includes a sheet of rigid transparent material suspended by a pair of first cables from a frame of the press. A lower edge of the sheet is displaced a predetermined distance above a bed of the press providing just enough room so that a forward portion of a workpiece can be slid beneath the lower edge of the sheet and positioned on the bed of the press without providing additional space through which an operator's hands can be inadvertently extended. An operator holds a rearward portion of the workpiece with both hands as a ram of the press comes down during a work cycle to engage and fabricate or form the forward portion of the workpiece positioned on the bed. Just before the fabrication begins, a second pair of cables connected to the sheet and passing through a series of pulleys alternately on the frame and ram of the press operates, as a consequence to movement of the ram, to rapidly move the sheet out of the way of the workpiece.

Abstract: The reed contact unit comprises a pair of aligned members of magnetizable and electrically conductive material spaced apart endwise from each other with a fillet of non-magnetic electrically conductive material inserted between the spaced ends of the members. The upper surfaces of the members and the fillet are coplanar. An electrically conductive cantilever carries an electrically conductive and magnetizable armature at its free end overlying the fillet and the adjacent ends of the members. Upon magnetization of the members, a contact surface of the armature contacts the members to complete an electric circuit between the cantilever and the members. The members and the cantilever are mounted within a hermetically sealed enclosure.

Abstract: A portable electrical device has a molded body having a cavity closed by a rear wall. Two conductive prongs project through the rear wall for reception into a phase port and a neutral port, respectively, of an electrical outlet. A retractable grounding pin or prong, when in an extended position, extends outwardly from the rear wall in parallel spaced relationship with the two prongs and is receivable by a ground port of the outlet if there is one. When the device is used with an electrical outlet not having a ground port, the grounding pin retracts within the cavity against a spring bias. An indicating pin is operatively connected to the grounding pin and moves, in response to retracting movement of the grounding pin, to an exposed position within a recess in a front wall of the body to provide a visual indication that the device is not grounded by the grounding pin.

Abstract: An electric receptacle for ordinary household or trade size junction boxes having a complete ground fault circuit interrupter incorporated in the receptacle, including electronic components to detect a ground fault on the load side of such receptacle, and a coil and trip mechanism which is actuated when a ground fault is detected. A number of the components are utilized in this invention in ways that enable them to perform multiple functions eliminating the need for separate components and the space they would require, thereby making it possible to install a complete ground fault circuit interrupter in a smaller space within a receptacle.

Abstract: A material for use in making electrical contacts is produced in a powder form suitable for later processing into electrical contacts by standard metallurgical techniques. The material consists of a first metal, such as silver, and the oxide of a second metal, such as cadmium, added to the first metal in a proportion up to the limits of solubility of the second metal in the first metal. An oxide of a third metal having a low electronic work function level, such as lithium oxide, is added and uniformly distributed on the surfaces of the powder particles by precipitation. A fourth metal, such as tellurium, that is insoluble in the first metal is also added to provide selected characteristics.

Abstract: A material for use in making electrical contacts is produced in a powder form suitable for later processing into electrical contacts by standard metallurgical techniques. The material consists of a first metal, such as silver, and the oxide of a second metal, such as cadmium, added to the first metal in a proportion up to the limits of solubility of the second metal in the first metal. An oxide of a third metal having a low electronic work function level, such as lithium oxide, is added and uniformly distributed on the surfaces of the powder particles by precipitation. A fourth metal, such as tellurium, that is insoluble in the first metal is also added to provide selected characteristics.

Abstract: A thermomagnetic switch is mountable on a chamber wall to extend into a liquid filled chamber. A reed switch in the switch is controlled by the strength of a magnetic field produced by a cylindrical magnet surrounding the reed switch. The magnetic flux passing through the reed switch is varied by a ferromagnetic cylindrical element having a magnetic permeability varying with temperature that shunts magnetic flux at a level varying with temperature. A ferrous slug or shaft adjacent to the reed switch is movable to shunt a selectable portion of the magnetic flux and permit a fine temperature adjustment. A method of adjusting the operating temperature of switch reduces the magnetic strength of the magnet in the switch in small increments while the switch is exposed to a selected temperature until the switch operates to establish its operating temperature.

Abstract: A terminal strip including a plurality of terminal blocks arranged in a row in side-by-side abutting relation by a pair of end clamps on a channel-shaped track. The track has an apertured base disposed between upturned side walls which terminate in respective outwardly turned flanges. Each terminal block comprises an open-sided molded part having a pair of spaced leg-like extensions extending downwardly from a juncture with the respective opposite side walls of the part and a bottom wall spaced between the leg-like extensions. The bottom wall is positioned between portions of the top side of the flanges of the track while flanges at the free ends of the leg-like extensions grip rear surface portions on the flanges to tightly position the block on the track. One of the leg-like extensions terminates in a lever comprising said flange and an outwardly and upwardly extending lever portion, and includes a necked portion joining a mid-point of said lever and said juncture.

Abstract: The reed contact unit comprises a pair of aligned members of magnetizable and electrically conductive material spaced apart endwise from each other. A fillet of non-magnetic electrically conductive material may be inserted between the spaced ends of the members. A flat electrically conductive resilient member supported at its opposite ends carries, at its mid-region, a magnetizable and electrically conductive armature and suspends it over the fillet and the adjacent end portions of the magnetizable members. Upon magnetization of the members, a lower contact surface of the armature engages the ends of the magnetizable members and completes an electric circuit from at least one of the magnetizable members through the resilient member to its support. The magnetizable members and the resilient member are mounted within a sealed enclosure.

Abstract: An electrical contact material which consists of a mixture of silver, 5 to 50 weight per cent of copper and 2 to 20 weight per cent of lanthanum, strontium chromite of formula La.sub.1-x Sr.sub.x CrO.sub.3, where the values of x lie between 0 and 1.0, formed as a hard, chemically inert, non-metallic phase of high electrical conductivity both within the bulk of, and at the surface of, the contact material. Methods of producing the electrical contact materials utilizing powder metallurgical techniques are outlined.

Abstract: The tool comprises a plurality of tubular telescoping sections of insulating material arranged in a series. Each of the sections, except a most rearward end section, has a forwardly facing annular exterior shoulder at its rearward end and each of the sections, except a most forward end section, has a rearwardly facing annular interior shoulder at its forward end. When the tool is fully extended for use, each rearwardly facing shoulder engages a forwardly facing shoulder and radial apertures in the sections are in alignment. A pin support located within the rearward end of each section except the most rearward section contains a pin which is biased outwardly by a compression spring through the aligned apertures thus locking the sections in their extended positions with respect to each other. The pins, aligned openings, and shoulders are relatively positioned so that pulling forces are opposed by the shoulders and not the pins.

Abstract: A ground fault detector for an ungrounded electrical distribution system responds to a wide range of ground fault current levels by providing the ground fault sensing circuitry with a high impedance at low ground fault signal levels and a low impedance at higher ground fault signal levels. The varying or nonlinear impedance of the sensing circuitry occurs due to the presence of the series combination of a Zener diode and a resistor connected in parallel with a level sensing means. At ground fault signals below the Zener voltage of the Zener diode, the impedance of the sensing circuitry is that of the level sensing means. When the ground fault signal exceeds the Zener voltage, the impedance of the sensing means is significantly reduced since the Zener resistor is now in effective parallel combination with the impedance of the level sensing means.

Abstract: A terminal connector or lug for use as a termination for electrical cables is formed by an impacting process. The connector comprises an apertured mounting pad portion and an integral cylindrical tubular body portion having an open end and a closed end and adapted to be crimped onto an electrical cable. The pad is of a generally rectangular parallelepiped shape and extends longitudinally outwardly from the closed end of the tubular portion adjacent an outer peripheral region thereof. Opposite side portions of the inner end portion of the pad extend inwardly of the closed end of the tubular portion, and the wall closing the closed end of the tubular portion is of uniform thickness and is perpendicular to an upper surface of the pad.

Abstract: The contact materials comprise silver with additions of mercury or mercury and tellurium and silver-cadmium oxide compositions with additions of mercury and tellurium. The methods of making the materials include the steps of adding a silver-mercury alloy to molten silver and to a molten silver-tellurium powder mixture. The materials including cadmium oxide are produced by heating a mixture of powders of silver, a cadmium-tellurium compound, cadmium oxide, and mercuric oxide powders in a reducing atmosphere and then reoxidizing.

Abstract: The contact materials comprise silver with additions of mercury or mercury and tellurium and silver-cadmium oxide compositions with additions of mercury and tellurium. The methods of making the materials include the steps of adding a silver-mercury alloy to molten silver and to a molten silver-tellurium powder mixture. The materials including cadmium oxide are produced by heating a mixture of powders of silver, a cadmium-tellurium compound, cadmium oxide, and mercuric oxide powders in a reducing atmosphere and then reoxidizing.