Abstract: A welding power supply including power conversion circuitry adapted to receive a primary source of power, to utilize one or more power semiconductor switches to chop the primary source of power, and to convert the chopped power to a welding output is provided. The provided welding power supply includes a pulse width modulated (PWM) digital controller including gate drive circuitry that generates a PWM output signal that controls the switching of the one or more power semiconductor switches. The PWM output signal includes a duty cycle term corrected for one or more sources of error in the welding system.

Abstract: A welding power supply including power conversion circuitry adapted to receive a primary source of power, to utilize one or more power semiconductor switches to chop the primary source of power, and to convert the chopped power to a welding output is provided. The provided welding power supply includes a pulse width modulated (PWM) digital controller including gate drive circuitry that generates a PWM output signal that controls the switching of the one or more power semiconductor switches. The PWM output signal includes a duty cycle term corrected for one or more sources of error in the welding system.

Abstract: A welding power supply including power conversion circuitry adapted to receive a primary source of power, to utilize one or more power semiconductor switches to chop the primary source of power, and to convert the chopped power to a welding output is provided. The provided welding power supply includes a pulse width modulated (PWM) digital controller including gate drive circuitry that generates a PWM output signal that controls the switching of the one or more power semiconductor switches. The PWM output signal includes a duty cycle term corrected for one or more sources of error in the welding system.

Abstract: A welding power supply including power conversion circuitry adapted to receive a primary source of power, to utilize one or more power semiconductor switches to chop the primary source of power, and to convert the chopped power to a welding output is provided. The provided welding power supply includes a pulse width modulated (PWM) digital controller including gate drive circuitry that generates a PWM output signal that controls the switching of the one or more power semiconductor switches. The PWM output signal includes a duty cycle term corrected for one or more sources of error in the welding system.

Abstract: A weld current generating apparatus includes a voltage conversion circuit, a control circuit, a switch circuit, and a current output circuit. The voltage conversion circuit receives an AC voltage from an AC voltage input terminal, and converts the AC voltage to a DC voltage. The control circuit receives the DC voltage, wherein the control circuit is capable of setting a weld time, and outputting a control signal for controlling the weld time. The switch circuit receives the control signal, and turns on for the weld time according to the control signal. The current output circuit outputs a continuous weld current when the switch circuit turns on.

Abstract: A seam welding apparatus and a seam welding method perform a seaming process on workpieces of various shapes having flange sections, by preventing a welding track formed by upper and lower rotary electrodes from becoming displaced from a welding reference line established on the flange section. The seam welding apparatus includes two rotary electrodes for gripping the flange section therebetween while seam-welding the flange section, a support for synchronizing movements of the two rotary electrodes with each other in a widthwise direction of the flange section, a turning mechanism for pressing at least one of the two rotary electrodes toward the workpiece body, a roller that abuts against an end face of the flange section, and roller adjusting means for positionally adjusting the roller.

Abstract: A device for resistance welding includes a welding clamp housing, a welding transformer, a welding clamp, a welding clamp drive for operating the welding clamp and a power supply using alternating supply voltage. The device may be built as small as possible and may be simple to expand. The power supply is implemented by a main converter and by drive and welding converters. The output of the main converter is connected to the inputs of the drive and welding converters. The inputs of the drive and welding converters are connected to one another. These connections are implemented by an a.c. voltage intermediate circuit.

Abstract: A weld current generating apparatus includes a voltage conversion circuit, a control circuit, a switch circuit, and a current output circuit. The voltage conversion circuit receives an AC voltage from an AC voltage input terminal, and converts the AC voltage to a DC voltage. The control circuit receives the DC voltage, wherein the control circuit is capable of setting a weld time, and outputting a control signal for controlling the weld time. The switch circuit receives the control signal, and turns on for the weld time according to the control signal. The current output circuit outputs a continuous weld current when the switch circuit turns on.

Abstract: A multi-compartment container for storage of food, personal and miscellaneous items. The container has a base with a bottom and a circular sidewall. Radial dividers for a plurality of generally pre-shaped individual compartments which may be integral or removable. An access opening with a closure is provided for each compartment. The center of the container defines a through aperture which may be used for support in a position of use or for receiving an accessory such as a small battery-powered light.

Abstract: The present invention is directed to a release composition for molds and formers used in the production of natural and synthetic latex articles. The release coating contains a water-borne, high Tg polymer formed from at least one hydrophobic monomer and at least one hydrophilic monomer, where the Tg of the polymer is at least −10° C. One advantage of the release composition is that it is compatible with a coagulant solution used in the formation of latex gloves. Articles formed using the release coating have good anti-blocking properties.

Abstract: A contol apparatus for a single-phase full-wave resistance welder in which anti-parallel connected thyristors are connected in series with a primary winding of a welding transformer and which controls a firing phase .theta.n of the thyristors to adjust a welding current, includes storage means for calculating and storing a square sum SK in such a manner that a sinusoidal value VK=K0sin.theta.K having a given peak value is divided at predetermined phase intervals (1.degree.) within a predetermined phase range (180.degree.), and the square sum SK=V1.sup.2 +V2.sup.2 +V3.sup.2 +. . . VK.sup.2 of the sinusoidal value VK with respect to each phase .theta.K is calculated in units of divided phases .theta.K (.theta.K=1.degree., 2.degree., 3.degree., . . . , 180.degree.) in advance, and Vx calculating means for reading out square sums Sn and Sm of the firing phase .theta.n and energization end phase .theta.

Abstract: An improvement in a method of welding the shanks of successive nails to a pair of wires to form a series of wire connected nails suitable for packaging and use in a power driven fastener driving device which includes the steps of connecting a pair of electrodes with a source of electrical current characterized by repetitive cycles and effecting repetitive nail-to-wire cycles each of which includes an initial movement of (1) the shank of an unattached nail (2) a pair of wires extending transversely thereacross and (3) the electrodes from a position of initial contact into a welding station wherein pressurized contact between the electrodes, the nail shank and the wires is maintained and a final movement out of the welding station to a final release position of the electrodes with respect to the welded together nail shank and wires.

Abstract: A resistance welding system having a low-inertia movable welding head coupled to a stationary welding transformer which is of low mutual reactance. Through an appropriate timing circuit and control, a high-energy pulse of current, of very short time duration, is transmitted through the welding transformer to the movable welding head. The welding head, which contacts a projection on overlapping components, effects a rapid welding of the components, and the welding head rapidly follows up the melting of the projection due to its low inertia.

Abstract: An AC voltage regulator which detects the instantaneous supply voltage in a phase shifter and compares it with the reference voltage by a comparator circuit so that in response to the output signals from the comparator, the firing angle of the thyristors connected to a supply voltage circuit may be controlled in order to maintain constant the effective load current.