Harmonic metal manufacturing wire reciprocation

Abstract

A harmonic wire oscillator is configured to oscillate a section of wire within a wire liner. The oscillator may include an actuator configured to oscillate the wire at a resonant frequency of the section of wire. The oscillation causes reciprocation of the wire at a tip of a torch.

Description

[0001] Cross - Reference to Related Applications

[0002] This application claims the benefit of U.S. Provisional Patent Application No. 62 / 890,256, filed on Aug. 22, 2019, entitled “Harmonic Metal Manufacturing Wire Reciprocation”. The entire content of U.S. Provisional Patent Application No. 62 / 890,256 is hereby incorporated by reference in its entirety. Technical Field

[0003] The present disclosure relates to welding - type devices and, more particularly, to reciprocating wire - feeding systems. Background Art

[0004] Many conventional welding systems and conventional welding control mechanisms have been implemented for various purposes. In continuous welding processes using consumable electrodes, gas metal arc welding (GMAW), and more particularly metal inert gas (MIG) or metal active gas (MAG) techniques (collectively GMAW), allow for the formation of continuous weld beads by feeding a wire electrode, which is protected by a gas (usually an inert gas or a gas containing an inert reagent or an active gas such as CO2 or oxygen), from a torch. Summary of the Invention

[0005] The present disclosure relates to a harmonic wire reciprocation system, substantially as illustrated in at least one of the accompanying drawings and described in conjunction with at least one of the accompanying drawings, as more fully set forth in the claims. Brief Description of the Drawings

[0006] Figure 1 is an illustration of an example welding - type system in accordance with aspects of the present disclosure.

[0007] Figure 2 is an illustration of an example torch that includes a wire reciprocation system.

[0008] Figure 3 is a flow chart of an example method for determining an oscillation frequency to be applied to a wire reciprocation system to meet a desired reciprocation frequency.

[0009] Figure 4 is a flow chart of an example method for electronically tuning the natural oscillation frequency of a reciprocation system.

[0010] The drawings are not necessarily to scale. Where appropriate, like or identical reference numerals are used to represent like or identical elements. Detailed Description

[0011] Some advanced welding forms using consumable electrodes include controlling the duration, frequency, voltage, and / or current of the short circuit between the wire electrode and the advancing weld pool formed by the molten metal of the workpiece and the wire electrode. One method of controlling short circuit behavior is to reduce the welding current during short circuit to arc and arc to short circuit transitions via current regulation or secondary switching in the welding power supply.

[0012] In some welding systems, a controlled short circuit can be generated by a reciprocating wire feeding system configured to oscillate the wire into and out of contact with the advancing weld pool. By oscillating the wire into and out of contact with the weld pool, the liquid at the end of the wire can be mechanically immersed into the weld pool and detached from the wire when the wire is pulled out of the weld pool, thus achieving a "controlled short circuit" effect. For traditional wire reciprocation techniques, the mechanical movement of the wire is slow, which limits the deposition capacity and / or welding speed. To obtain a desired higher deposition and faster welding travel speed, the wire moves bidirectionally at a speed exceeding 1000 inches per minute and at a rate exceeding 100 Hz at 100% duty cycle. Traditional reciprocating wire feeding systems use bidirectional motors, and bidirectional motors typically have high torque requirements to overcome the inertia of the motor, drive rolls, and / or gears. Bidirectional motors can have limitations on the reciprocation frequency (which in turn limits the wire feed and travel speed as well as productivity), may be prone to overheating, and / or may be oversized, which can cause reduced accessibility of the weld joint at the torch.

[0013] U.S. Patent Application Publication No. 2017 / 0182580, titled "Reciprocation Wire Feed Welding System and Method" by Christopher Hsu, Dennis Roland Sigl, and Herbert Alexius Bankstahl, discloses a reciprocating wire feeding system that includes a wire reciprocator located within a wire feeder. The entire content of U.S. Patent Application Publication No. 2017 / 0182580 is incorporated herein by reference. U.S. Patent Application Publication No. 2019 / 0099769, titled "Metal Manufacturing Systems and Methods Using Mechanical Oscillation" by Todd Earl Holverson and Christopher Hsu, discloses a mechanical oscillation system configured to mechanically oscillate a welding tool. The entire content of U.S. Patent Application Publication No. 2019 / 0099769 is incorporated herein by reference.

[0014] The present disclosure relates to oscillating a wire electrode by using the wire electrode as a spring and using a force actuator mass as a harmonic resonator to reciprocate the wire electrode at the nozzle of a torch. Compared with conventional reciprocating wire feeding systems (e.g., systems using a bidirectional motor), the present disclosure provides several advantages, including increased reliability and smaller and / or lower-cost parts.

[0015] The disclosed example torch includes: a wire guide configured to guide a wire electrode fed from a wire feeder to a first end of the torch for delivery to a welding application, the wire guide defining a gap region within which the wire electrode can oscillate when a force transverse to the travel path of the wire electrode is applied within the gap region; and an actuator configured to apply a force to the wire electrode within the gap region in at least one direction at a first frequency to cause the wire electrode to oscillate within the gap region.

[0016] Some example torches further include a linkage having a hole through which the wire electrode is passed, and the actuator is configured to apply a force to the linkage to cause the wire electrode to oscillate within the gap region.

[0017] In some example torches, the mass of the linkage is adjustable.

[0018] In some example torches, the actuator is a coil configured to generate a magnetic field, and the linkage includes a magnet.

[0019] In some example torches, the resonant oscillation frequency of the wire electrode within the gap region is at least 25 Hertz.

[0020] In some example torches, the first frequency is the resonant oscillation frequency of the wire electrode within the gap region.

[0021] In some example torches, the wire guide includes at least one wedge clutch before the gap region along the length of the wire guide, and the clutch allows the wire electrode to move in a forward direction toward the first end of the torch and restricts the wire electrode from moving in a backward direction away from the first end.

[0022] In some example torches, the oscillation of the wire electrode within the gap region is configured to cause the wire electrode to provide a reciprocating movement at a frequency twice the first frequency at the first end of the torch.

[0023] In some example torches, the actuator is a motor configured to directly apply a force to the wire electrode within the gap region.

[0024] In some example torches, the gap region includes a guide configured to restrict the movement of the wire electrode within the gap region to a single plane.

[0025] In some example torches, the wire guide includes a plurality of rollers, and the gap region includes a spacing between successive rollers.

[0026] In some example torches, the length of the gap region can be adjusted by adjusting the spacing. In some example torches, the spacing is adjusted by adding or removing rollers.

[0027] Some example torches also include control circuitry configured to determine a first frequency based on the type of wire, the diameter of the wire, the length of the gap region defined by the endpoints of the gap region, and the mass of the material that will oscillate within the gap region, and to control an actuator based on the determined first frequency.

[0028] In some example torches, the control circuitry determines the frequency by determining the spring constant of the wire based on the type of wire, the diameter of the wire, and the length of the gap region.

[0029] In some example torches, the actuator is a rotary motor that drives a cam.

[0030] In some example torches, the determined first frequency is the resonant frequency of the wire within the gap region.

[0031] In some example torches, the wire guide includes a free roller and a one-way roller, and the gap region is between a first contact point between the free roller and the wire and a second contact point between the one-way roller and the wire.

[0032] In some example torches, the torch is a GMAW torch.

[0033] As used herein, the terms "welding-type power supply", "welding-type power source", and "welding-type system" denote any device capable of supplying welding, cladding, plasma cutting, induction heating, laser (including laser welding, laser hybrid, and laser cladding), carbon arc cutting or gouging, and / or resistance preheating when power is applied thereto, including but not limited to transformer-rectifiers, inverters, converters, resonant power supplies, quasi-resonant power supplies, switched-mode power supplies, etc., and associated control circuitry and other auxiliary circuitry.

[0034] As used herein, the term "welding-type power" denotes power suitable for welding, plasma cutting, induction heating, CAC-A, and / or hot wire welding / preheating (including laser welding and laser cladding).

[0035] As used herein, the term "welding-type output" denotes an output signal suitable for welding, plasma cutting, or induction heating.

[0036] As used herein, the term "torch" or "welding-type tool" may include a hand-held torch or a robotic torch, a welding gun, or other devices for generating a welding arc.

[0037] As used herein, the term "welding mode" refers to the type of process or output being used, such as CC, CV, pulsed, MIG, TIG, spray, short circuit, etc.

[0038] As used herein, a welding operation includes the actual welding of two or more solid objects (e.g., resulting in a joint such as welding or brazing, cladding, texturing, and / or heat treating of the solid objects, and / or cutting of the solid objects) and simulated or virtual welding (e.g., visualization of welding without actual solid welding taking place).

[0039] For convenience, the term "power" is used throughout this specification, but also includes related measures such as energy, current, voltage, and enthalpy. For example, controlling "power" may include controlling voltage, current, energy, and / or enthalpy, and / or controlling based on "power" may include controlling based on voltage, current, energy, and / or enthalpy. Electric power, measured in watts as the product of voltage and current (e.g., V*I power), is referred to herein as "wattage".

[0040] As utilized herein, the terms "circuit" and "circuitry" refer to physical electronic components (i.e., hardware) as well as any software and / or firmware ("code") that may configure the hardware, be executed by the hardware, and / or otherwise be associated with the hardware. As used herein, for example, a particular processor and memory may include a first "circuit" when executing a first line or more of code, and may include a second "circuit" when executing a second line or more of code.

[0041] As used herein, the terms "control circuit" and "control circuitry" may include digital and / or analog circuitry, discrete circuitry, and / or integrated circuit systems, microprocessors, digital signal processors (DSPs), and / or other logic circuitry and / or associated software, hardware, and / or firmware. The control circuit may include a memory as well as a processor that executes instructions stored in the memory. The control circuit or control circuitry may be located on one or more circuit boards that form part or all of a controller and are used to control a welding process, devices such as a power source or a wire feeder, motion, automation, monitoring, air filtration, a display, and / or any other type of welding-related system.

[0042] As used herein, the terms "memory" and / or "memory device" refer to computer hardware or circuitry that stores information for use by a processor and / or other digital device. The memory and / or memory device can be any suitable type of computer memory or any other type of electronic storage medium, such as read-only memory (ROM), random access memory (RAM), cache memory, compact disc read-only memory (CDROM), electro-optical memory, magneto-optical memory, programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), flash memory, solid-state storage devices, computer-readable media, or the like.

[0043] Figure 1 FIG. illustrates an example arc welding system 100 for performing a welding operation. As shown, in Figure 1 the arc welding system, a power supply 10 and a wire feeder 12 are coupled via a conductor or conduit 14. In the illustrated embodiment, the power supply 10 is separate from the wire feeder 12 such that the wire feeder can be positioned at a distance from the power supply near the welding location. However, in some instances, the wire feeder can be integrated with the power supply 10. In these cases, the conduit 14 will be internal to the system. In instances where the wire feeder 12 is separate from the power supply 10, terminals are typically provided on the power supply and on the wire feeder 12 to allow the conductor or conduit to be coupled to the system to permit power and gas to be provided from the power supply 10 to the wire feeder 12 and to allow data to be exchanged between the two devices.

[0044] The system is configured to supply a welding wire, power, and a shielding gas to a torch 16. The torch 16 can be any type of arc welding torch (e.g., GMAW, GTAW, FCAW, SAW) and can permit the welding wire 42 (e.g., an electrode wire) and the gas to be fed to a location adjacent to the workpiece 18. A second conductor extends to the welded workpiece 18 to complete the circuit between the power supply 10 and the workpiece 18.

[0045] The welding system is configured such that welding settings are selected by an operator and / or a welding sequence (such as, selected via an operator interface 20 provided on the power supply 10). The operator interface 20 will typically be incorporated into the front panel of the power supply 10 and may allow selection of settings such as, for example, the welding process, the type of welding wire to be used, voltage and current settings, and the like. The system may be configured to allow welding with various steel, aluminum, or other welding wires that are fed through the torch 16. Additionally, the system may be configured to use welding wires having various cross-sectional geometries (e.g., circular, substantially flat, triangular, etc.). These welding settings are communicated to a control circuit 22 within the power supply 10. The system may be specifically adapted to implement welding programs configured for certain electrode types.

[0046] The control circuit 22, described in more detail below, operates to control the generation of a welding power output that is supplied to the welding wire 42 to perform a desired welding operation. In the "short circuit" mode, under the influence of the heat of the welding arc, droplets of molten material form on the welding wire 42, and these droplets are periodically transferred to the workpiece 18 by contact or short circuit between the welding wire 42 and the droplets 80 and the workpiece 18. In this manner, the system and / or the control circuit 22 controls the generation of the weld of the workpiece 18 by adjusting one or more operating characteristics of the system during the welding process. The operating characteristics may include, but are not limited to, wire feeder speed, wire feeder direction, travel speed, power output, process mode, deposition path, deposition sequence, torch angle, etc.

[0047] Power from the power supply 10 is applied to the welding wire 42 via, for example, a welding cable 52. Similarly, a shielding gas is fed through the wire feeder 12 and the welding cable 52. During a welding operation, the welding wire 42 is advanced through the sheath of the welding cable 52 toward the torch 16. The workpiece cable and fixture 49 allow a closed circuit to be maintained from the power supply through the torch 16, the electrode (welding wire) 42, and the workpiece 18 to sustain the welding arc during operation.

[0048] This arc welding system may allow control of successive voltage and / or current levels and / or pulse durations based on previous current and duration measurements to control the promotion, occurrence, duration, and interruption of short circuit events between the welding wire electrode and the advancing weld pool. Specifically, the current peak in the waveform may be adjusted based on one or more previous short circuit events or aspects of the short circuit events (such as, the duration of the short circuit event).

[0049] The control circuit 22 is coupled to the power conversion circuit 24. This power conversion circuit 24 is adapted to generate output power, for example, a pulse waveform applied to the welding wire 42 at the torch 16. Various power conversion circuits can be used, including choppers, boost circuit systems, buck circuit systems, inverters, converters, and the like. The configuration of such circuit systems can itself be of a type well known in the art. The power conversion circuit 24 is coupled to a power source, as indicated by arrow 26. The power applied to the power conversion circuit 24 can be sourced from the power grid, but other power sources can also be used, for example, power generated by an engine-driven generator, a battery, a fuel cell, or other alternative sources. Figure 1 The illustrated power supply 10 can also include an interface circuit 28 that is configured to allow the control circuit 22 to exchange signals with the wire feeder 12.

[0050] The wire feeder 12 includes a complementary interface circuit 30 coupled to the interface circuit 28. In some embodiments, a multi-pin interface can be provided on both components, and a multi-conductor cable extends between the interface circuits to allow settings such as wire feed speed, process, selected current, voltage, or power level, and the like to be made on the power supply 10, the wire feeder 12, or both.

[0051] The wire feeder 12 also includes a control circuit 32 coupled to the complementary interface circuit 30. As described below, the control circuit 32 allows the wire feed speed to be controlled according to the operator's selection or stored or determined sequence instructions, and allows these settings to be fed back to the power supply via the interface circuit. The control circuit 32 is coupled to an operator interface 34 on the wire feeder, which allows the selection of one or more welding parameters, specifically, the wire feed speed. The operator interface can also allow the selection of welding parameters such as process, type of wire utilized (e.g., material and diameter), current, voltage, or power settings, and the like. The control circuit 32 can also be coupled to a gas control valve 36 that regulates the flow of shielding gas to the torch. Typically, such gas is provided during welding and can be turned on immediately before welding and continue for a short time after welding. The gas applied to the gas control valve 36 can be provided in the form of a pressurized bottle, as indicated by reference numeral 38.

[0052] The wire feeder 12 includes components for feeding a welding wire to the torch 16 and thus to a welding application under the control of the control circuit 32. For example, one or more spools 40 of welding wire are accommodated in the wire feeder 12. The welding wire 42 is unwound from the spool and gradually fed to the torch 16. The spool 40 may be associated with a clutch 44 that releases the spool 40 when the welding wire is to be fed to the torch 16. The clutch 44 can also be adjusted to maintain a minimum friction level to prevent free rotation of the spool 40. A first wire feeder motor 46 may be disposed within a housing 48 to engage a wire feed roller 47 to push the welding wire from the wire feeder 12 toward the torch 16.

[0053] In practice, at least one of the rollers 47 is mechanically coupled to the motor 46 and rotated by the motor 46 to drive the welding wire 42 from the wire feeder 12, while a mating roller is biased toward the welding wire to maintain good contact between the two rollers and the welding wire 42. Some systems may include multiple rollers of this type. A tachometer 50 or other sensor may be provided to detect the speed of the first wire feeder motor 46, the roller 47, or any other associated component in order to provide an indication of the actual wire feed speed. A signal from the tachometer 50 is fed back to the control circuit 32, such as for continuous or periodic monitoring, calibration, etc. In some instances, the system includes a welding wire spool motor for rotating the wire feeding device, and the welding wire spool motor can be similarly adjusted to increase or decrease the amount of welding wire between the wire feeder motors.

[0054] Other system arrangements and input schemes may also be implemented. For example, the welding wire can be fed from a bulk storage container (e.g., a drum) or from one or more spools outside the wire feeder. Similarly, the welding wire can be fed from a "spool gun" that is mounted on or near the torch. As described herein, the wire feed speed setting can be input via an operator interface 34 on the wire feeder, on the operator interface 20 of the power supply, or on both. In a system for adjusting the wire feed speed to the torch, this can be the input for setting.

[0055] The torch 16 may include a wire oscillation system that oscillates the welding wire 42, causing the welding wire to reciprocate at a controllable frequency at the nozzle 60 of the torch 16.

[0056] Figure 2 A schematic diagram showing an example torch (e.g., Figure 1 torch 16) that includes a wire oscillation system. The torch 16 may include a wire liner that includes pins or rollers 51. A clearance zone 53 is formed in the liner within the torch 16, and the clearance zone 53 is a space without pins. Within the torch 16, an actuator 54 applies a force to the welding wire 42 within the clearance zone 53 via a linkage 55 through which the welding wire 42 is fed.

[0057] Example linkage 55 has a hole through which wire 42 fed from wire feeder 12 extends. Actuator 54 applies a force to linkage 55 in a direction transverse (e.g., perpendicular) to the direction of travel of wire 42 through linkage 55. The force moves wire 42 in the direction of the force (e.g., to a displacement limit position 57 away from actuator 54). Since wire 42 is fixed at one end of gap region 53 (e.g., via a freewheeling clutch 65 as described below), the end of wire 42 is retracted as wire 42 is displaced from natural rest center position 58 towards displacement limit positions 57 and 59.

[0058] As wire 42 is displaced, wire 42 stores energy in the form of tension in response to the force applied by actuator 54 and linkage 55. When the force is relaxed and / or the tension in wire 42 overcomes the force from actuator 54, wire 42 moves back past natural rest center position 58 when actuator 54 is not applying a force. Thus, by periodically or continuously applying a force in at least one direction, actuator 54 can cause wire 42 to oscillate.

[0059] The combination of wire 42 and linkage 55 has a natural frequency or resonant frequency ω o , which is based on the system mass m (i.e., the mass of wire 42 and linkage 55 within the gap region) and the spring constant k. The spring constant k is based on the wire material and the length of gap region 53.

[0060] And ω o = 2πf where f is the frequency in hertz

[0061] In some examples, the mass of linkage 55 and the length of gap region 53 are selected such that the natural frequency f n is at least 25 hertz. In some examples, the mass of linkage 55 and the length of gap region 53 are selected such that the natural frequency f n is at least 50 hertz. Decreasing the length of gap region 53 increases k and thus increases the natural frequency f n . Similarly, increasing the length of gap region 53 decreases k and thus decreases the natural frequency f n . Oscillation of wire 42 within gap region 53 causes wire 42 to reciprocate at the nozzle 60 of torch 16. Decreasing the system mass m (e.g., by decreasing the mass of linkage 55) increases the frequency f n , while increasing the mass m decreases the frequency f n .

[0062] The reciprocation frequency f r is the oscillation frequency fn Twice that is because whenever the wire 42 moves away from the natural rest center position 58 towards the displacement limit positions 57 and 59, the wire 42 reciprocates (i.e., is pulled back away from the workpiece 18 towards the torch 16) at the nozzle 60 of the torch 16. Example displacement limit positions 57 and 59 can be the points of the maximum oscillation amplitude or the points where the oscillatory motion changes direction. Thus, if the oscillation frequency f is 50 Hz, then the reciprocation frequency is 100 Hz.

[0063] At least one of the pins in the wire liner is a one-way overrunning clutch 65, and this one-way overrunning clutch 65 only allows the wire to move in the forward direction. For example, the overrunning clutch 65 can be a wedge clutch. The overrunning clutch 65 allows the wire 42 fed by the wire feeder 12 to move forward towards the torch nozzle 60, rather than move backward towards the wire feeder 12. The overrunning clutch 65 prevents the reciprocating motion from decaying by preventing the wire 42 from moving back towards the wire feeder 12.

[0064] In some examples, the length of the clearance zone 53 can be adjusted by removing the roller 51 or adding a roller 51 to the wire liner. In some examples, the length of the clearance zone can be adjusted by adjusting the spacing between the roller 51 and the subset 72 of the overrunning clutch 65. The subset 72 of the rollers can be included in a bracket with an adjustable length. The spacing of the subset 72 of the rollers is increased by increasing the width of the bracket. In some examples, the spacing of the subset 72 of the rollers can be adjusted manually. In some examples, the spacing of the subset 72 of the rollers can be electronically controlled. For example, the controller 62 can control the actuator 74, and this actuator 74 adjusts the spacing of the subset 72 of the rollers. An example actuator 74 can include a motor that drives a worm (i.e., a worm drive), and the worm expands and contracts the spacing of the subset 72 of the rollers. Adjusting the spacing of the subset of the rollers correspondingly increases or decreases the length of the clearance zone 53, and thus increases or decreases the resonant frequency of the wire 42.

[0065] The wire 42 reciprocates or retracts a distance d 63 at the torch nozzle 60. The distance d 63 is equal to 2(h - x). h is equal to the distance between the displacement limit position 57 and the point 70, where the point 70 is the rear end of the clearance zone (e.g., where the wire 42 contacts the wedge clutch 65). x is equal to the distance between the natural rest center position 58 and the point 70. In other words, x is equal to half of the length of the clearance zone 53.

[0066] In some examples, the actuator 54 is an electromagnet (e.g., a coil or solenoid) that generates a magnetic field, and the linkage 55 is magnetic (e.g., a ferromagnet). The magnetic field generated by the electromagnet (i.e., the actuator 54) pushes the magnet (i.e., the linkage 55) toward the displacement limit position 57. In some examples, the electromagnet (i.e., the actuator 54) can pull the magnet (i.e., the linkage 55) toward the displacement limit position 59. In some examples, the electromagnet (i.e., the actuator 54) is at a resonant frequency f n Generate a magnetic field. For example, if the electromagnet (i.e., actuator 54) generates a magnetic field that causes the magnet (i.e., linkage 55) to feel a force in a direction away from the electromagnet (i.e., actuator 54), then the electromagnet (i.e., actuator 54) may be turned on for at least a certain duration during the time when the welding wire 42 moves from the displacement limit position 59 to the displacement limit position 57. Then, during the time when the welding wire 42 moves from the displacement limit position 57 to the displacement limit position 59, the electromagnet (i.e., actuator 54) may be turned off. Therefore, the electromagnet (i.e., actuator 54) is at a resonant frequency f n is activated.

[0067] The controller 62 can control the frequency of the actuation force generated by the actuator 54. In some examples, the operator can input parameters (mass, gap region, and wire type) that determine the resonant frequency into an interface (e.g., the operator interface 34 or the interface circuit 28) in the system, and the controller 62 controls the actuation frequency based on the input parameters. The controller 62 can communicate with the control circuit 32 of the wire feeder 12 and / or the control circuit 22 of the power supply 10. In some examples, for a given gap region length, mass m, and wire type (e.g., material and diameter), the resonant frequency f can be determined empirically. n Next, the controller 62 may determine the natural frequency f based on the empirically determined n The actuator 54 is controlled to apply a force at the actuation frequency.

[0068] In some examples, controller 62 may receive a desired reciprocation frequency and control actuator 74 to adjust the spacing of subset of rollers 72 to obtain the gap zone required to achieve the desired reciprocation frequency.

[0069] In some examples, controller 62 runs a tuning test to determine the length of the gap zone required to achieve a desired reciprocating frequency (i.e., a natural frequency of the combination of welding wire 42 and linkage 55 that will achieve a desired reciprocating frequency, where the reciprocating frequency is twice the frequency of the combination of welding wire 42 and linkage 55). For example, controller 62 may control actuator 54 to apply a force to welding wire 42 via linkage 55, and then empirically determine the natural frequency of the combination of welding wire 42 and linkage 55 by counting the oscillations of the system over a given period of time.

[0070] The controller 62 can detect the oscillation (e.g., via the sensor 76). The sensor 76 can be any sensor that detects the movement of the welding wire 42 across a position. For example, the sensor 76 can be an optical sensor, a Hall effect sensor, an inductive sensor, or the like. In some instances, when the actuator 54 is an electromagnet and the linkage 55 is a magnet, the movement of the magnet induces a current in the coil of the electromagnet (i.e., the actuator 54). The controller 62 can detect the voltage spike induced in the coil by the movement of the magnet (i.e., the linkage 55) caused by the oscillation of the welding wire 42.

[0071] If the determined natural frequency is less than the desired frequency, then the controller 62 controls the actuator 74 to increase the spacing of the subset 72 of rollers. Increasing the spacing of the subset 72 of rollers decreases the length of the gap region 53, which increases the natural frequency of the combination of the welding wire 42 and the linkage 55.

[0072] Similarly, if the determined natural frequency is greater than the desired frequency, then the controller 62 controls the actuator 74 to decrease the spacing of the subset 72 of rollers. Decreasing the spacing of the subset 72 of rollers increases the length of the gap region 53, which decreases the natural frequency of the combination of the welding wire 42 and the linkage 55.

[0073] The controller 62 can iteratively run the test until the desired natural frequency is reached. In some instances, during the welding operation, the controller 62 can determine the natural frequency of the combination of the welding wire 42 and the linkage 55 and control the actuator 74 to adjust the spacing of the subset 72 of rollers in response to the determined natural frequency.

[0074] In some instances, the oscillatory movement of the welding wire 42 within the gap region is restricted to a plane that includes the shift limit positions 57, the natural rest center position 58, and the shift limit position 59. A guide (e.g., a track) can only allow the linkage 55 to move up and down within the track, thereby restricting the movement of the welding wire 42 to a plane that includes the shift limit positions 57, the natural rest center position 58, and the shift limit position 59.

[0075] In some instances, the actuator 54 can be a motor that applies a mechanical force to the linkage 55 (e.g., the linkage 55 can be connected to a cam driven by a rotary motor). The linkage 55 can have a needle-like shape, where the end of the needle is connected to the motor shaft, and the welding wire 42 is fed through the eye of the needle.

[0076] Although illustrated as part of the torch 16, in some instances, the oscillation system (including the linkage 55, the actuator 54, and the controller 62) can be included within the wire feeder 12.

[0077] Figure 3is a flowchart representative of example machine-readable instructions 300 that may be executed by Figure 1 system 100 to determine an oscillation frequency and apply a force at that oscillation frequency to a wire electrode via an actuator. The machine-readable instructions 300 may be implemented in part or in whole by Figure 2 controller 62.

[0078] In block 302, controller 62 receives information related to the length of gap region 53. The length of gap region 53 may be determined by the number of rollers 51 installed. The length of gap region 53 is increased by removing rollers 51 and decreased by adding rollers 51. In some examples, an operator may input an indication of the length of gap region 53 (e.g., based on the number of rollers 51 installed or the number of rollers 51 removed from a baseline number of rollers) into an interface (e.g., operator interface 20 of power supply 10 or operator interface 34 of wire feeder 12). The information is then transmitted to controller 62 via one or more cables 75. In some examples, the information may be transmitted via welding cable 52.

[0079] In block 304, controller 62 receives information related to the mass of linkage 55. This information may be included in the memory of the controller. In some examples, the mass is adjustable and an operator may input an indication of the mass of linkage 55 into an interface (e.g., operator interface 20 of power supply 10 or operator interface 34 of wire feeder 12). In block 306, controller 62 receives information related to the type of wire electrode 42 (e.g., wire material type and diameter). This information may be sent from control circuit 22 of power supply 10 or control circuit 32 of wire feeder 12 to controller 62, for example, based on an input received at operator interface 20 or operator interface 34.

[0080] In block 308, controller 62 determines the spring constant k of the selected wire electrode. Controller 62 may include a memory that includes a look-up table, and controller 62 may look up the spring constant from the look-up table based on the determined wire type and the determined length of gap region 53.

[0081] In block 310, controller 62 determines the resonant frequency of the combination of wire electrode 42 and linkage 55, where the resonant frequency f n is determined based on the following formula.

[0082]

[0083] In block 312, the controller 62 receives information indicating a minimum reciprocation frequency, which can be determined based on the selected welding process. The reciprocation frequency information can be sent from the control circuit 22 of the power supply 10 or the control circuit 32 of the wire feeder 12 to the controller 62.

[0084] In block 314, the controller 62 controls the actuator 54 to apply a force to the linkage 55 at a multiple of the resonant frequency f n that satisfies the minimum reciprocation frequency received in block 312. This reciprocation frequency is twice the oscillation frequency. For example, if the minimum reciprocation frequency is 100 Hz and the determined resonant frequency is 60 Hz, then the controller 62 will control the actuator 54 to apply a force at the first multiple of the resonant frequency (i.e., 60 Hz) such that the actual reciprocation frequency is 120 Hz, which is higher than 100 Hz. However, if the minimum reciprocation frequency is 100 Hz and the determined resonant frequency is 35 Hz, then the controller 62 will control the actuator 54 to apply a force at the second multiple of the resonant frequency, which will result in an actual reciprocation frequency of 140 Hz. If the controller controls the actuator 54 to apply a force at the first multiple of the resonant frequency, then the actual reciprocation frequency will be 70 Hz, which will be lower than the minimum reciprocation frequency. Thus, the controller determines the lowest multiple of the resonant frequency that satisfies the minimum reciprocation frequency.

[0085] Figure 4 is a flowchart representative of example machine-readable instructions 400 that can be executed by Figure 1 system 100 to electronically adjust the length of the gap region 53 to tune the natural frequency of the combination of the wire 42 and the linkage 55. The machine-readable instructions 400 can be implemented, in part or in whole, by Figure 2 controller 62.

[0086] In block 402, the controller 62 receives information indicating a desired reciprocation frequency, which can be determined, for example, based on the selected welding process. The reciprocation frequency information can be sent from the control circuit 22 of the power supply 10 or the control circuit 32 of the wire feeder 12 to the controller 62. The desired natural frequency is equal to half of the desired reciprocation frequency.

[0087] In block 404, the controller 62 commands the actuator 54 to apply a force to the linkage 55 to cause the combination of the wire 42 and the linkage 55 to oscillate within the gap region 53.

[0088] In block 406, the controller 62 determines the actual natural frequency of the combination of the wire 42 and the linkage 55. The controller 62 detects the number of times the combination of the wire 42 and the linkage 55 oscillates within a given time period to determine the actual natural frequency.

[0089] In block 408, the controller 62 determines whether the actual natural frequency is less than a threshold amount (e.g., one percent, two percent, etc.) than the desired natural frequency. If the controller 62 determines that the actual natural frequency is less than the threshold amount than the desired natural frequency (block 408), then in block 410, the controller 62 commands the actuator 74 to increase the spacing of the subset 72 of rollers. Increasing the spacing of the subset 72 of rollers will decrease the length of the gap region 53, which will increase the natural frequency of the combination of the wire 42 and the linkage 55. In some instances, the amount by which the controller 62 commands the actuator 74 to increase the spacing is based on the magnitude of the difference between the actual natural frequency and the desired natural frequency. In other words, the controller may command the actuator to increase the spacing of the subset 72 of rollers in proportion to the amount of the difference between the actual natural frequency and the desired natural frequency. In some instances, in block 410, the actuator may increase the spacing by a set distance. The controller 62 then returns to block 404 to repeat the testing process.

[0090] If the controller 62 determines that the actual natural frequency is not less than the threshold amount than the desired natural frequency (block 408), then in block 412, the controller 62 determines whether the actual natural frequency is greater than a threshold amount (e.g., one percent, two percent, etc.) than the desired natural frequency. If the controller 62 determines that the actual natural frequency is greater than the threshold amount than the desired natural frequency (block 412), then in block 414, the controller 62 commands the actuator 74 to decrease the spacing of the subset 72 of rollers. Decreasing the spacing of the subset 72 of rollers will increase the length of the gap region 53, which will decrease the natural frequency of the combination of the wire 42 and the linkage 55. In some instances, the amount by which the controller 62 commands the actuator 74 to decrease the spacing is based on the magnitude of the difference between the actual natural frequency and the desired natural frequency. In other words, the controller may command the actuator to decrease the spacing of the subset 72 of rollers in proportion to the amount of the difference between the actual natural frequency and the desired natural frequency. In some instances, in block 414, the actuator may decrease the spacing by a set distance.

[0091] If the controller 62 determines that the actual natural frequency is not greater than the threshold amount than the desired natural frequency (block 412), then in block 416, the controller 62 determines that no adjustment to the spacing of the subset 72 of rollers is needed. In some instances, the controller 62 may send a signal to the control circuit 22 of, for example, the welding power supply 10 or the control circuit 32 of the wire feeder 12, the signal indicating that the reciprocating system is tuned for the desired reciprocating frequency.

[0092] As used herein, "and / or" means any one or more of the items in the list connected by "and / or". By way of example, "x and / or y" means any element in the three-element set {(x), (y), (x, y)}. In other words, "x and / or y" means "one or both of x and y". As another example, "x, y and / or z" means any element in the seven-element set {(x), (y), (z), (x, y), (x, z), (y, z), (x, y, z)}. In other words, "x, y and / or z" means "one or more of x, y and z". As used herein, the term "exemplary" means serving as a non-limiting instance, example, or illustration. As used herein, the terms "for example" and "such as" introduce a list of one or more non-limiting instances, examples, or illustrations. As used herein, a circuit system is "operable" to perform a function as long as the circuit system includes the hardware and code (if any is required) necessary to perform the function, regardless of whether the performance of the function is disabled or not enabled (e.g., by user-configurable settings, factory trim, etc.).

[0093] Although the methods and / or systems of the present invention have been described with reference to certain embodiments, those skilled in the art will understand that various changes can be made and equivalents can be substituted without departing from the scope of the methods and / or systems of the present invention. For example, the blocks and / or components of the disclosed embodiments can be combined, divided, rearranged, and / or otherwise modified. In addition, many modifications can be made to adapt a particular situation or material to the teachings of the present disclosure without departing from the scope of the present disclosure. Accordingly, the methods and / or systems of the present invention are not limited to the particular embodiments disclosed. Indeed, the methods and / or systems of the present invention will include all embodiments that literally and under the doctrine of equivalents fall within the scope of the appended claims.

Claims

1. A welding torch, comprising: a wire guide configured to guide a wire fed from a wire feeder to a first end of the welding torch for delivering the wire to a welding application, the wire guide defining a gap region in which the wire oscillates when a force transverse to the travel path of the wire is applied to the wire within the gap region, wherein the wire guide includes a plurality of rollers, the gap region includes a spacing between successive rollers, and the length of the gap region is adjustable by adjusting the spacing, the spacing being adjusted by adding or removing rollers; and an actuator configured to apply the force to the wire within the gap region in at least one direction transverse to the travel path of the wire at a first frequency to cause the wire to oscillate within the gap region.

2. The welding torch according to claim 1, further comprising a linkage having a hole through which the wire is passed, wherein the actuator is configured to apply the force to the linkage to cause the wire to oscillate within the gap region.

3. The welding torch according to claim 2, wherein the first frequency is at least partially based on the mass of the linkage.

4. The welding torch according to claim 2, wherein the actuator is a coil configured to generate a magnetic field, and wherein the linkage includes a magnet.

5. The welding torch according to claim 1, wherein the resonant oscillation frequency of the wire within the gap region is at least 25 hertz.

6. The welding torch according to claim 1, wherein the first frequency is the resonant oscillation frequency of the wire within the gap region.

7. The welding torch according to claim 1, wherein the wire guide includes at least one wedge clutch before the gap region along the length of the wire guide, wherein the clutch allows the wire to move in a forward direction toward the first end of the welding torch and restricts the wire from moving in a backward direction away from the first end.

8. The welding torch according to claim 7, wherein the oscillation of the wire within the gap region is configured to cause the wire to provide a reciprocating movement at a frequency twice the first frequency at the first end of the welding torch.

9. The welding torch according to claim 1, wherein the actuator is a motor configured to directly apply the force to the wire within the gap region.

10. The welding torch according to claim 1, wherein the gap region includes a guide configured to restrict the movement of the wire within the gap region to a single plane.

11. The welding torch according to claim 1, wherein the actuator is a rotary motor that drives a cam.

12. The welding torch according to claim 1, wherein the welding torch is a gas metal arc welding (GMAW) torch.

13. A welding torch, comprising: A wire guide configured to guide a wire fed from a wire feeder to a first end of the torch to deliver the wire to a welding application, the wire guide defining a gap region in which the wire can oscillate when a force transverse to the travel path of the wire is applied to the wire within the gap region; An actuator configured to apply the force to the wire within the gap region in at least one direction at a first frequency to cause the wire to oscillate within the gap region; And A control circuit system configured to: determine the first frequency based on the type of wire, the diameter of the wire, the length of the gap region defined by the endpoints of the gap region, and the mass of the material to be oscillated within the gap region, and control the actuator based on the determined first frequency.

14. The torch according to claim 13, wherein the control circuit system determines the frequency by determining a spring constant of the wire based on the type of the wire, the diameter of the wire, and the length of the gap region.

15. The torch according to claim 13, wherein the determined first frequency is a resonant frequency of the wire within the gap region.

16. A torch comprising: A wire guide configured to guide a wire fed from a wire feeder to a first end of the torch to deliver the wire to a welding application, the wire guide defining a gap region in which the wire can oscillate when a force transverse to the travel path of the wire is applied to the wire within the gap region, wherein the wire guide includes a free idler wheel and a one-way idler wheel, and wherein the gap region is between a first contact point between the free idler wheel and the wire and a second contact point between the one-way idler wheel and the wire; And An actuator configured to apply the force to the wire within the gap region in at least one direction at a first frequency to cause the wire to oscillate within the gap region.

17. The torch according to claim 16, further comprising a linkage mechanism having a hole through which the wire is passed, wherein the actuator is configured to apply the force to the linkage mechanism to cause the wire to oscillate within the gap region.

18. The torch according to claim 16, wherein the first frequency is a resonant oscillation frequency of the wire within the gap region.

19. The torch according to claim 16, wherein the actuator is a motor configured to directly apply the force to the wire within the gap region.

20. The torch according to claim 16, wherein the gap region includes a guide configured to restrict movement of the wire within the gap region to a single plane.

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