Abstract: A method and apparatus for a generator driven CV welding power supply includes a generator driven by an engine, and a CV electronic field controller. The generator includes a field winding and a welding output winding. The electronic field controller is connected to the field winding and has an engine feedback input. The controller also has a voltage boost circuit responsive to the engine RPM (or engine speed command signal). A wire feeder includes a motor powered by the generator output, and the boosted field current helps start the wire feeder when the engine is idling. The speed of the engine is reduced when there is no welding arc.

Abstract: A method and apparatus for providing welding power includes a power supply that receives utility and engine power. The power supply has an engine power input and a utility power input. One of the engine power input and the utility power input is selectively connected to the power supply in response to a mode select input, controlled by an input selector. The input selector may include a user selectable input, such as a sensor circuit or a user switch on a welder control panel, preferably a three position switch having an engine mode position, a utility mode position and an off position in various alternatives. The engine is disabled when utility power is selected. Disabling the engine includes one or more of cutting the field current, starter current, and/or battery current. The power supply may include an inverter, chopper, and/or a phase controlled device. The welder is preferably a single-package, stand-alone welder, and/or includes an engine/generator having a welding and an auxiliary output.

Abstract: A method and apparatus for induction heating includes a power supply, and a controller, and an induction head. The induction head includes a flexible coiled, such as one formed with Litz wire. The head also includes a thermal insulator, for disposing between the head and the workpiece. The insulator reflects heat back to the workpiece, protecting the coil, but is transparent to inductive (E-M) energy. The power supply is a variable output frequency power supply, such as one having a resonant tank, to adapt to the inductance of the head.

Abstract: First and second CV power sources are connected in parallel. The first CV source provides an output sufficient for welding. The second CV source also has an output sufficient for welding, but at is at a voltage less than the voltage of the output of the first CV source and may also have a lower current output. Voltage from the first CV source is blocked from being applied to the second CV source, preferably by diodes or SCRs. The second CV source is a background source with a secondary and a rectifier, preferably a center tapped secondary with a full wave rectifier, and an inductor between the output. The first CV source is a welding source with a secondary and a rectifier, preferably a center tapped secondary with a full wave rectifier, and an inductor between the rectifier and the output.

Abstract: A spark gap assembly includes two conductive spark gap points forming a spark gap. Two substantially identical, non-conductive, molded plastic pieces are clamped together to make a housing with at least one cylindrical receptacle for the spark gap points. Two conductive leads electrically contact the spark gap points and abut and electrically contact circuit board leads when the assembly is mounted on a circuit board. The housing pieces include at least one fastening hole and a fastener extends through the fastening holes when the pieces are assembled, thus clamping the together. The two pieces have at projections on the bottom that are received in holes on the board, thereby positioning the pieces.

Abstract: A method and apparatus for providing welding power includes controlling a phase controlled power circuit to provide a reduced OCV output. Preferably, the output is controlled in response to feedback, such as current being less than or greater than a threshold.

Abstract: A method and apparatus for providing welding type power is disclosed. The power source is capable of receiving any input voltage over a wide range of input voltages and includes an input rectifier that rectifies the ac input into a dc signal. A dc voltage stage converts the dc signal to a desired dc voltage and an inverter inverts the dc signal into a second ac signal. An output transformer receives the second ac signal and provides a third ac signal that has a current magnitude suitable for welding, cutting or induction heating. The welding type current may be rectified and smoothed by an output inductor and an output rectifier. A controller provides control signals to the inverter and a controller power supply can also receive a range of input voltages and provide a control power signal to the controller, and a voltage independent of the input voltage.

Abstract: A short circuit arc welding system is disclosed. The control scheme uses a current command signal to drive the output current. The command signal is comprised of a long-term current command that sets the long-term current command level and a real-time or short-by-short current command. Arc voltage feedback is used to determine if the desired arc length is present and to adjust the long-term command. The short-by-short current command is derived from real-time arc current feedback and is used to control the burn-off rate by an instantaneous, or short-by-short, adjustment of the current command. A function of the time derivative of arc power, less the time derivative of arc current, is used to detect, in real time, when the short is about to clear. A stop algorithm is employed that monitors the arc on a short-by-short basis. When the process is ending a very low current level is provided to avoid forming a ball.

Abstract: An induction heating power supply is disclosed. It includes a power circuit having at least one switch and a power output. The output circuit includes an induction head. The output circuit is coupled to the power output. A controller has at least one feedback input connected to the output circuit, and has a control output connected to the switch. The controller predicts the switch zero crossing and preferably soft switches the switch. Current feedback is obtained from a coil placed between the bus bars. Each bus bar is comprised of multiple plates to increase current capacity.

Abstract: A plasma arc cutting power supply, and method of providing plasma cutting power, is disclosed. It includes a source of power having, preferably an engine or transformer based power source, that provides a main power output and an auxiliary power output. A two-state configuration circuit is in electrical communication with the auxiliary power output. The auxiliary power output receives voltage of a first magnitude with a non-floating ground when the configuration circuit is in its first state. The auxiliary power output receives voltage of a second magnitude, preferably different than the first magnitude, with a floating ground, when the configuration circuit is in its second state. When a plasma cutting circuit is connected to the auxiliary power output the configuration circuit is set in its second state. The plasma cutting circuit includes at least one chopper. A safety circuit that disables the plasma output includes a GFI or optical isolator.

Abstract: A method and apparatus for providing welding power includes two power sources (first and second), each having an output. A linking circuit selectively connects the power sources in one of an independent mode (such that each is connected to a separate welding output whereby the first welding output is independent of the second welding output) or a combined mode (such that the power sources are connected in parallel and connected to one welding output whereby the outputs of the first power source and second power source are combined). A controller includes a mode selector to allow the user to select between the independent mode and the combined mode. Also, the controller includes a master output magnitude selector, which is a single selector, that controls the magnitude of the output of both power sources when the user has selected the combined mode. The power sources can be operated in a CV or CC mode when independent, or a CC mode when combined.

Abstract: A method and apparatus for welding with an engine driven inverter power supply includes generating an ac output with an engine and generator. The output is rectified and inverted to provide an ac inverter output. The engine is controlled using feedback indicative of a welding output operating parameter. The feedback may also be taken from the inverter or generator, and the generator may be controlled instead of or in addition to the engine. Engine parameters that may be controlled include engine speed, selecting between an idle speed and a run speed, a throttle position, a fuel pump, an injection timer, a fuel to air ratio, fuel consumption and ignition timing. Another aspect of the invention is having the feedback be responsive to one or more of the welding current, welding voltage, welding power, or functions thereof. The feedback may be responsive to the current, voltage, power, ripple and functions thereof.

Abstract: A transformer and method of making a transformer is disclosed. The transformer has a magnetic core, a first winding and a second winding. The first and second windings are wound about the core, and an insulating jacket, which includes a plurality of protrusion, mounted about the core. One of the first and second windings is wound about the insulating jacket. The core is preferably a toroid core in one embodiment. Some of the anchors are on the inner diameter of the insulating jacket, and other on the outer diameter of the insulating jacket. The anchors are preferably spaced at equal circumferential positions. The windings are a progressive windings, with various sections, and each section has a number of layers. Each progressive section is anchored by at least two of the anchors. The first and second windings are wound directly on the core insulation, and the insulating jacket is mounted directly on the core.

Abstract: A power supply, such as a plasma cutting power supply or a welding power supply, that provides an output to a pair of output terminals is disclosed. The power supply includes a source of voltage and a plurality of choppers. The choppers are connected in parallel between the voltage source output terminals. A controller controls the choppers so that they are out-of-phase with respect to each of the other of the plurality of choppers. The choppers preferably include a freewheeling diode, an inductor and a switch. The number of choppers is approximately equal to the ratio of the open circuit voltage to the output load voltage.

Abstract: A method and apparatus for providing submerged arc welding power is disclosed. The power supply is AC/DC, and may be controlled in either a CV or a CC mode. The power supply includes a cycloconverter that provides a single phase output and receives a three phase input. A controller includes a PI current regulator for operation in the CC mode. The controller also includes a PI voltage regulator. When the CV mode is selected, the voltage and current regulators are cascaded such that the output of the voltage regulator is the set point input to the current regulator.

Abstract: A method and system for system for welding a workpiece is disclosed. The workpiece is preheated while the weld is being performed. The preheating is performed fast enough that it can be done on-the fly-immediately in advance of the weld. The preheating is preferably accomplished with an induction heating system. The induction coil is mounted with the welding torch such that as the torch is moved along the weld path, the coil precedes it, preheating the weld path.

Abstract: A welding power supply includes an input rectifier that receives sinusoidal or alternating line voltage and provides a rectified voltage. A pre-regulator provides a dc bus and a convertor, such as a boost convertor, provides a welding output. The pre-regulator is an SVT (slow voltage transition) and an SCT (slow current transition) switched convertor. It may include a snubber circuit having a diode that is SVT switched. Also, the boost convertor may be SVT and SCT switched. The pre-regulator preferably includes a power factor correction circuit. The power source includes, in one embodiment, an inverter having a snubber circuit having a first switch in anti-parallel with a first diode, and a second switch in anti-parallel with a second diode. The first switch and first diode are connected in series with the second switch and the second diode, and the first and second switches are connected in opposing directions, to form a switched snubber.

Abstract: A welding machine with a wire feeder and a controller is disclosed. The wire feeder includes a wire feed motor with a motor speed input. The controller is coupled to the motor speed control input. A user selectable wire feed speed input is also connected to the controller. The controller has an input circuit coupled with a non-linear stage such that the relationship between the user selectable wire feed speed input and the actual wire feed speed is not linear. The selectable input may be a potentiometer mounted on a front panel as the user selectable wire feed speed input. The non-linearity may be continuous or two discrete gains.

Abstract: A method and apparatus of anodizing a component, which is placed in an electrolyte solution. A number of pulses are applied to the solution and component. Each pulse is formed by a pattern having three magnitudes. The third magnitude is less than the first and second magnitudes, and all three magnitudes have the same polarity. The pulse pattern may include alternations between the first and second magnitudes, and following the alternations, the third magnitude. The fluid enters the reaction chamber from a transport chamber through a plurality of inlets directed toward the component, at an angle of between 60 and 70 degrees. The inlet is the cathode, and the component is the anode. Current flows between the cathode and the anode. The inlets are in a side wall where the fluid enters the reaction chamber substantially horizontally. The reaction chamber has at least one outlet beneath the inlets. Which may be in a bottom wall. The fluid follows a return path.

Abstract: A method and apparatus for making reusable paint. rollers comprised of a core formed from thermoplastic material. The thermoplastic material is formed into a core about a stationary mandril. An adhesive is then applied to the core whereupon a cover is bonded thereto. In a first embodiment the core is formed by winding a plurality of thermoplastic strips about the mandril. In a second embodiment the core is formed by applying liquefied thermoplastic material to a driven belt which transfers the thermoplastic material to the mandril.