Abstract: A method and apparatus for feeding wire from a source of wire to a weld includes one or more motors disposed adjacent the wire to drive the wire to the weld. A buffer is disposed between the source and an arc end of the torch. Another motor may be disposed near the wire source. A wire tension controller may be provided. The one or more motors advance and retract the wire, and wire is stored, or the path length altered, when the wire is retracted.

Abstract: A method and apparatus for feeding wire in a welding system include one or more motors disposed adjacent the wire to drive it. A wire feed motor is also disposed along the wire path, and is closer to the source of wire than the torch, and closer to the source than the one or more motors. The motors may be a pair motors disposed on opposite sides of the wire and move the wire to and away from an arc end of a torch. They preferably reversing the direction of the wire within one process cycle. The or more motors may be a stepper motor, a servo motor, a zero backlash motor, a gearless motor, a planetary drive motor, or a linear actuator (such as a piston), in various embodiments.

Abstract: A method and apparatus for short circuit welding includes providing welding power suitable for short circuit welding, sensing the stick out length, and adjusting the welding speed, such as wire feed speed or travel speed, adjusting a welding parameter, or adjusting thee gas mixture in response thereto. Stick out is preferably determined by measuring a welding parameter, and performing an FFT on the parameter, and then calculating stick out, in one embodiment. Stick out can be either CTTWD or CPTPD. The system can determine when a short is about to clear by calculating a value Vc defined by Vc=d/dt(kl*dp/dt), and comparing Vc to a Vthreshhold, which varies in response to welding cycle history.

Abstract: A method and apparatus for welding includes one or more of a welding type power source, a feedback circuit, a wire feeder and a controller. The controller preferably has an eta control circuit responsive to the feedback. It also has a control loop having a response time responsive to the eta output. The controller detects whether or not the process is a fast-tack process, and controls the supply of power according to a first control scheme is the process is a fast-tack process, and according to a second control scheme if the process is not a fast-tack process. The controller sets the run-in wire feed speed as a percentage of weld wire feed speed, preferably obtaining the percentage from the weld wire feed speed potentiometer at start up. The controller enters a calibration mode at start up if a calibration pendant is attached and on. In the calibration mode calibration receiving values from the front panel potentiometers.

Abstract: A method and apparatus for welding include initiating a pulse welding process includes initiating a welding arc by providing CC type welding power, maintaining the arc by providing CV type power. Then, pulse type welding power is provided. The method and system can be used to start short circuit, or other welding processes by providing short circuit power, or welding power of a given mode, instead of providing pulse power. Also, in one alternative, a method and system of initiating a pulse, short circuit, or given welding process includes initiating a welding arc by providing CC type welding power at least until a pseudo-equilibrium for the arc is established. Then, providing welding power in a pulse, short circuit, or the given mode.

Abstract: A method and apparatus for multi process welding includes providing a controlled short circuit output and a pulse output in response to a user selection across a workpiece output stud and a torch output stud.

Abstract: A method and apparatus for controlling a welding-type power supply includes providing a current wave form having an arc current portion and a short circuit current portion. An arc state is entered by retracting a welding wire, and a short circuit state is entered by advancing the wire. The current enters the arc current portion prior to the creation of the arc and the current enters the short circuit current portion prior to the creation of the short, by coordinating the wave form with the wire retraction. This may be preformed on a wire having a diameter of 2.4 mm or more to a weld and applying a welding current of less than 100 amps, or of less than 35 amps. One current waveform during the arc state includes at least three segments, and the last segment is entered into prior to the short circuit state being entered, and is the same current magnitude as the current magnitude at the start of the short circuit state.

Abstract: A method and apparatus for feeding wire from a source of wire to a weld includes one or more motors disposed adjacent the wire to drive the wire to the weld. A buffer is disposed between the source and an arc end of the torch. Another motor may be disposed near the wire source. A wire tension controller may be provided. The one or more motors advance and retract the wire, and wire is stored, or the path length altered, when the wire is retracted.

Abstract: A method and apparatus for controlled short circuit welding includes providing welding-type power and controlling the welding-type power to be controlled short circuit power. A user selectable heat control input is received and the heat content of a drop, each drop, or a plurality of drops is adjusted in response thereto.

Abstract: A method and apparatus for feeding wire in a welding system include one or more motors disposed adjacent the wire to drive it. A wire feed motor is also disposed along the wire path, and is closer to the source of wire than the torch, and closer to the source than the one or more motors. The motors may be a pair motors disposed on opposite sides of the wire and move the wire to and away from an arc end of a torch. They preferably reversing the direction of the wire within one process cycle. The or more motors may be a stepper motor, a servo motor, a zero backlash motor, a gearless motor, a planetary drive motor, or a linear actuator (such as a piston), in various embodiments.

Abstract: A method and apparatus for controlled short circuit welding includes providing welding-type power and controlling the welding-type power to be controlled short circuit power. A user selectable heat control input is received and the heat content of a drop, each drop, or a plurality of drops is adjusted in response thereto.

Abstract: A method and apparatus for multi process welding includes providing a controlled short circuit output and a pulse output in response to a user selection across a workpiece output stud and a torch output stud.

Abstract: A method and apparatus for welding include initiating a pulse welding process includes initiating a welding arc by providing CC type welding power, maintaining the arc by providing CV type power. Then, pulse type welding power is provided. The method and system can be used to start short circuit, or other welding processes by providing short circuit power, or welding power of a given mode, instead of providing pulse power. Also, in one alternative, a method and system of initiating a pulse, short circuit, or given welding process includes initiating a welding arc by providing CC type welding power at least until a pseudo-equilibrium for the arc is established. Then, providing welding power in a pulse, short circuit, or the given mode.

Abstract: A method and apparatus for short circuit welding includes providing welding power suitable for short circuit welding, sensing the stick out length, and adjusting the welding speed, such as wire feed speed or travel speed, adjusting a welding parameter, or adjusting thee gas mixture in response thereto. Stick out is preferably determined by measuring a welding parameter, and perforrming an FFT on the parameter, and then calculating stick out, in one embodiment. Stick out can be either CTTWD or CPTPD. The system can determine when a short is about to clear by calculating a value Vc defined by Vc=d/dt(kl*dp/dt), and comparing Vcto a Vthreshhold, which varies in response to welding cycle history.

Abstract: A method and apparatus for short circuit welding, or a gas source therefor, includes providing a pulse gas to a welding location and initiating a short circuit welding process. The type of gas being provided is changed after the process has been established. Alternatively, it includes a gas source therefor, and further includes mixing at least two types of gas components and providing the mixture to a welding location, and initiating a short circuit welding process. The mixture is subsequently changed. The process can be a hybrid welding including providing short arc type welding power and intermittently providing pulse type welding power.

Abstract: A method and apparatus for welding includes one or more of a welding type power source, a feedback circuit, a wire feeder and a controller. The controller preferably has an eta control circuit responsive to the feedback. It also has a control loop having a response time responsive to the eta output. The controller detects whether or not the process is a fast-tack process, and controls the supply of power according to a first control scheme is the process is a fast-tack process, and according to a second control scheme if the process is not a fast-tack process. The controller sets the run-in wire feed speed as a percentage of weld wire feed speed, preferably obtaining the percentage from the weld wire feed speed potentiometer at start up. The controller enters a calibration mode at start up if a calibration pendant is attached and on. In the calibration mode calibration receiving values from the front panel potentiometers.

Abstract: A current path for a mig welding gun assures a reliable and stable interface between a welding gun and a weld wire. In one embodiment, the current path is through a conductive insert that fits in the welding gun diffuser. Fingers of the insert resiliently contact the weld wire and thereby provide stable paths for welding power from the gun to the weld wire. In another embodiment, a contact tip assembly comprises a contact tip having resilient fingers in electrical contact with a body. An inner frusto-conical surface of a sleeve is urged against concentric frusto-conical outer surfaces of the fingers to bias the fingers radially inwardly against the weld wire. An insulative liner in the contact tip guides the weld wire between the fingers. A shield surrounds the contact tip and the sleeve. In a further embodiment, a single finger is pivotally connected to the contact tip. A spring biases a finger end against the weld wire.

Abstract: A method and apparatus for welding includes one or more of a welding type power source, a feedback circuit, a wire feeder and a controller. The controller preferably has an eta control circuit responsive to the feedback. It also has a control loop having a response time responsive to the eta output. The controller detects whether or not the process is a fast-tack process, and controls the supply of power according to a first control scheme is the process is a fast-tack process, and according to a second control scheme if the process is not a fast-tack process. The controller sets the run-in wire feed speed as a percentage of weld wire feed speed, preferably obtaining the percentage from the weld wire feed speed potentiometer at start up. The controller enters a calibration mode at start up if a calibration pendant is attached and on. In the calibration mode calibration receiving values from the front panel potentiometers.

Abstract: A method and apparatus for controlling a welding-type power supply includes providing a current wave form having an arc current portion and a short circuit current portion. An arc state is entered by retracting a welding wire, and a short circuit state is entered by advancing the wire. The current enters the arc current portion prior to the creation of the arc and the current enters the short circuit current portion prior to the creation of the short, by coordinating the wave form with the wire retraction. This may be preformed on a wire having a diameter of 2.4 mm or more to a weld and applying a welding current of less than 100 amps, or of less than 35 amps. One current waveform during the arc state includes at least three segments, and the last segment is entered into prior to the short circuit state being entered, and is the same current magnitude as the current magnitude at the start of the short circuit state.

Abstract: A method and apparatus for feeding wire in a welding system include one or more motors disposed adjacent the wire to drive it. A wire feed motor is also disposed along the wire path, and is closer to the source of wire than the torch, and closer to the source than the one or more motors. The motors may be a pair motors disposed on opposite sides of the wire and move the wire to and away from an arc end of a torch. They preferably reversing the direction of the wire within one process cycle. The or more motors may be a stepper motor, a servo motor, a zero backlash motor, a gearless motor, a planetary drive motor, or a linear actuator (such as a piston), in various embodiments.