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 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 that provides welding-type power is disclosed. It includes a power source, a welding output, an inductor winding and an auxiliary winding. The inductor winding is in electrical communication with the power source and the welding output. The auxiliary winding is preferably in magnetic communication with the inductor winding, and in electrical communication with the power source and the welding output. A switch is in electrical communication with the auxiliary winding, a controller with a control output is connected to the switch, the auxiliary winding is anti-parallel with the inductor winding in the preferred embodiment. The auxiliary winding may be used to create a variable output inductance.

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 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 that provides welding-type power is disclosed. It includes a power source, a welding output, an inductor winding and an auxiliary winding. The inductor winding is in electrical communication with the power source and the welding output. The auxiliary winding is preferably in magnetic communication with the inductor winding, and in electrical communication with the power source and the welding output. A switch is in electrical communication with the auxiliary winding, a controller with a control output is connected to the switch, the auxiliary winding is anti-parallel with the inductor winding in the preferred embodiment. The auxiliary winding may be used to create a variable output inductance.

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: An operator controllable transformer having a variable inductor with a control coil is provided. The transformer includes phase control circuitry to control the output of the transformer by phase controlling current flow in the control coil, thereby controlling the current provided to the load.

Abstract: An operator controllable transformer having a shunt magnetic path with a control coil is provided. The transformer includes phase control circuitry to control the output of the transformer by phase controlling current flow in the shunt coil, thereby controlling the flux through the shunt magnetic path and the flux coupling with the secondary coil. Power for the control circuitry is derived from the current induced in the shunt coil.

Abstract: A transformer having a shunt magnetic path and a shunt coil is provided. The transformer includes control circuitry to control the output of the transformer by controlling current flow in the shunt coil, thereby controlling the flux through the shunt magnetic path and the flux coupling with the secondary coil. The current in the shunt coil is phase-controlled and power for the control circuitry is derived from the current induced in the shunt coil.

Abstract: A constant speed drive differential assembly (10) has an input end plate (11), a rotatable housing (17), and an output end plate (18). A gear motor (12) comprising meshing spur gears (13, 14) mounted on shafts (15, 16) are arranged in the housing (17). A driving gear (20) is fixed to one of the shafts (15 or 16) and meshes with an ouput gear (21) fixed to a cover plate (19) which is rotatable with respect to the housing (17) as a result of differential over-or-under-rotation effected by the spur gears (13, 14). A governor/speed controlled valve (28) external of the housing (17) connects a fluid source from an external pump (27) to one side (40) or the other side (41) of the meshing spur gears (13, 14) in response to an overspeed or underspeed condition of the input speed transmitted to the assembly (10).

Abstract: The problem of providing a high speed torque measuring apparatus (10) is solved by first and second coaxial members (18, 20) having an elastic coupling (25) which interconnects the coaxial members for allowing relative angular displacement in proportion to the magnitude of a torque load applied to one of the members. First and second concentric apertures (32 and 34a, 34b) are provided in the first and second coaxial members, respectively, for movement into overlapping relationship in response to the relative angular displacement of the coaxial members. A light source (40) is provided on one side of the coaxial members for transmitting light through the aperture in both members when in their overlapping relationship whereby the transmitted light intensity is in proportion to the amount of overlap between the apertures. A light intensity detecting device (42) is provided for receiving the light transmitted through the overlapped apertures.

Abstract: A method of scavenging air and oil from a component (3) of an aircraft for returning the oil to a reservoir (4) for recirculation to the component involves the use of a gear pump (1) for scavenging the oil and gas. The gear pump centrifugally separates oil from the air and returns only the separated oil to the reservoir through outlets located upstream of the mesh zone of the gears while the air is discarded whereby lower discharge pressure of the gear pump is attained and there is no longer a need for a separate air-oil separator.

Abstract: A cavitating centrifugal pump which includes a housing defining a pumping chamber. An impeller is rotatable in the pumping chamber and includes a plurality of impeller blades designed for forming trailing vapor cavities within a liquid in the chamber to generate low pressure regions behind the blades upon rotation of the impeller. A fluid inlet is provided to the chamber radially inwardly of the low pressure regions and in communication therewith. A fluid outlet is provided from the chamber radially outwardly of the fluid inlet and in an area of the chamber whereby the fluid can be pumped from the chamber. Liquid inlets are provided to the chamber in the area of the impeller blades for flushing the low pressure regions behind the blades.