Abstract: A control system for resistance welders of the type in which welding current is supplied to a workpiece through a transformer. The system assures weld quality by monitoring the change in resistance across the weld during the welding operation without the need for auxillary leads or separate sensing transducers at or near the workpiece and automatically terminates the welding current when a quality weld is made as determined by resistivity characteristics of the weld. The system monitors discrete changes in the characteristics of the current in the primary of the welding transformer which occur as a result of changes in weld resistance. The system compares the monitored current characteristics of the welding current with a plurality of parameters indicative of a quality weld and terminates the welding current when a selected number of monitored characteristics are within selected parameters.

Abstract: The switch is of the type, known per se, in which an induction coil is driven by an oscillator. The coil is initially positioned in an end cap and secured therein by potting with epoxy resin. This allows the coil and cap to be handled as a unit during manufacture without damage to the coil. The switch is calibrated and adjusted automatically by abrading away part of a resistive layer on a circuit substrate. The circuitry of the switch has its lower potential side coupled to the housing via a capacitor, by means of a conductive adhesive tape trapped between the housing and an end closure.

Abstract: An assembly for restraining movement of a plurality of cables within an electrical housing including a pair of mating elements which, upon being operably associated, form a passageway therebetween for the passage of cables. Each mating element has a plurality of spaced-apart, outwardly extending finger layers on opposite sides of the passage and further includes a recessed receiving portion intermediate each of the finger layers for receiving a portion of the finger layers of the associated mating element.

Abstract: An anchoring device for a conductor including an elongated main body which has a recess that has a gripping jaw slideably supported therein. A cover having a corresponding recess and a corresponding jaw in the recess. The cover is pivotally supported on the main body so it can be opened for receipt of a conductor and is closed and the jaws released to produce a gripping force on the conductor. The clamping device also has biasing means for biasing the corresponding jaw towards one end of the clamp to produce an initial gripping force on the conductor.

Abstract: A solid-state, multistage temperature controller for automatically controlling the operation of fans to maintain the temperature of an associated engine within preselected limits.

Abstract: A versatilely cnnectible bus bar assembly adapted to carry 200-800 amperes in a panelboard or switchboard environment. The assembly includes a plurality of aluminum bus bars having generally rectangular cross-section bases and integrally connected generally U-shaped cross-sectioned plug-on protions extending throughout the length of the bus bars along the top part of the base. The plug-on portion is provided with inwardly directed nubs designed to prevent improper jaw connection. The bottom of each base includes a T-shaped slot extending throughout the length of the bus bar. Each of the bus bars is supported by a plurality of insulating bases, each of which includes a separate channel in engagement with the base of each bus bar. Each bus bar is fastened to each base by a T-bolt and nut. The head of the bolts are received in the T-shaped slot of the bus bars and the nuts are received in recesses provided on the underside of the base.

Abstract: This disclosure depicts a novel light fixture having a base, a support section and a cover with means for connecting electrical components on the base with electrical lighting components on the support section. The support section and cover can be assembled and disassembled from the base without the use of any tools.

Abstract: This disclosure depicts a novel abort cycle timer circuit for use with an AC source of electrical power and for operating electrical controls for machinery. The circuit provides a substantially DC voltage and current, first and second relays with normally open and normally closed contacts and a timing abort circuit. Opening a first of two switches causes the second of the two relays to energize after a time delay. Opening both switches causes the second relay to deenergize after a predetermined time. The novel circuit has improved immunity to electrical and magnetic noise.

Abstract: A frequency transducer for monitoring frequency in a power line wherein a frequency representative signal is generated which is twice the frequency of the signal to be monitored in the power line, the frequency representative signal is shaped into a triggering output signal which is supplied as one input to a comparator in a comparator/timer circuit. A second input to the comparator is provided by a timing circuit which produces a reference signal as that second input, said reference signal having a constant non-zero duration, the magnitude of which is dependent upon the timing constant of a resistive-capacitive circuit; said resistive-capacitive circuit being charged by a constant charging current of high value to ensure that variances in the timing constant due to temperature, humidity, contamination and the like are small when considered as a percentage figure.

Abstract: An interlock assembly for preventing two electrical control devices from simultaneously assuming a closed or "ON" position. The assembly comprises two subassemblies which are operably connected by a push/pull flexible cable. Each subassembly includes a frame member which carries a reciprocally movable plunger unit. A stop link is pivotally connected to the plunger unit at one end and carries a guide rod at its opposite end. The guide rod is retained within a guideway formed in the frame member which has a main longitudinally extending portion and an offset portion. The plunger unit is prevented from reciprocal movement to a depressed position when the guide rod is in the offset portion whereas reciprocal movement of the plunger unit to a depressed position is permitted when the guide rod is in the main portion of the guideway.

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.

Abstract: A power factor monitoring and control system for controlling the quality of a spot weld made by assembly line welders. The control system of the present invention detects a change in the load power factor as the weld is formed which is manifested as a change in the current extinction angle of the half cycles of weld current. The time interval between the instant weld current is extinguished at the end of a programmed half cycle and an instant when current is extinguished at the end of a subsequent half cycle provides a measure of the resistance across the weld nugget. The time interval information is stored and compared with information provided during a previous half cycle to generate a difference signal. The change in resistance in the secondary circuit is reflected through the transformer to the transformer primary circuit as a decrease in power factor.

Abstract: This disclosure depicts a novel environmentally sealed and manually controlled swivel unit for use in an adjustable lighting fixture. The swivel unit comprises a base for establishing electrical and mechanical connection with a source of electrical power and is attached to a housing having a central housing bore. The swivel unit further comprises a swivel ball device having a spherical body and a tube extending from the spherical body with a means for sealing the swivel ball device within the housing. A lamp-holder is attached to the end of the tube. The swivel unit also comprises a minimum friction swivel ball controller and circular plate and a tension means for forcing the swivel ball controller against the swivel ball device, and, in turn, for forcing the swivel ball device against a shoulder of the housing. This defines a predetermined lamp-holding force.

Abstract: An interfacing apparatus for a programmable controller having input modules of limited input compatibility and an input signal adjusting circuit for adjusting the input signals to make them compatible with the input modules.

Abstract: A multipole circuit breaker having a housing with a top wall center recess receiving a center strut of an interior trim. An operating assembly is interconnected with a trip assembly through a transistor link passing beneath the center recess and is operable by the magnetic assembly to assist the operating assembly in separating the breaker contacts in response to a fault current. A closure member overlapped by the interior trim prevents access to the load wires. A voltage reject configuration is provided on the housing to prevent mounting in a panelboard designed to carry voltages higher than that for which the circuit breaker is rated and a jaw assembly for the breaker is disclosed having a plurality of contact positions with each leg of a U shaped bus stab.

Abstract: An arc chute for a high voltage load interrupter switch has a pair of closely spaced side walls defining an arc chamber. An inner side of each wall has at least one groove between an open outer end of the chamber and an inner area of the chamber where blade contact is first broken resulting in a electrical arc. The longer axes of the grooves are generally perpendicular to the direction of flow of expanding arc gases that form at an inner end of the chamber when the switch is opened under load. The grooves have a semi-teardrop shaped cross section with the deeper portions of the grooves nearer the outer end of the chamber. As the expanding arc gases flow toward the chamber opening, some gas flows into the grooves which function as vortex generators causing the gases to swirl.