Patent Description:
Welding torches undergo wear and tear due to a variety of factors. Welding torch contact tips may experience added wear and tear due, at least in part, to their close proximity with the high temperature welding arcs that the welding torches produce. Contact tip wear and tear may be exacerbated by the high temperatures produced by the welding arcs.

<CIT> discloses a welding torch system includes a diffuser assembly that includes a locking mechanism to receive a contact tip.

Limitations and disadvantages of conventional and traditional approaches will become apparent to one of skill in the art, through comparison of such systems with the present disclosure as set forth in the remainder of the present application with reference to the drawings.

The present disclosure is directed to a welding torch as defined in claim <NUM> and a method for cooling a contact tip of the welding torch as defined in claim <NUM>.

These and other advantages, aspects and novel features of the present disclosure, as well as details of an illustrated example thereof, will be more fully understood from the following description and drawings.

Preferred examples of the present disclosure are described hereinbelow with reference to the accompanying drawings. In the following description, well-known functions or constructions are not described in detail because they may obscure the disclosure in unnecessary detail. For this disclosure, the following terms and definitions shall apply.

As utilized herein, the terms "e.g." and "for example" set off lists of one or more non-limiting examples, instances, or illustrations.

As used herein, a welding-type power supply and/or power source refers to any device capable of, when power is applied thereto, supplying welding, cladding, plasma cutting, induction heating, laser (including laser welding, laser hybrid, and laser cladding), carbon arc cutting or gouging and/or resistive preheating, including but not limited to transformer-rectifiers, inverters, converters, resonant power supplies, quasi-resonant power supplies, switch-mode power supplies, etc., as well as control circuitry and other ancillary circuitry associated therewith.

Welding-type power, as used herein, refers to power suitable for welding, cladding, plasma cutting, induction heating, CAC-A and/or hot wire welding/preheating (including laser welding and laser cladding), carbon arc cutting or gouging, and/or resistive preheating.

The terms "coupled," "coupled to," and "coupled with" as used herein, each mean a structural and/or electrical connection, whether attached, affixed, connected, joined, fastened, linked, and/or otherwise secured. As used herein, the term "attach" means to affix, couple, connect, join, fasten, link, and/or otherwise secure. As used herein, the term "connect" means to attach, affix, couple, join, fasten, link, and/or otherwise secure.

The terms "about" and/or "approximately," when used to modify or describe a value (or range of values), position, orientation, and/or action, mean reasonably close to that value, range of values, position, orientation, and/or action. Thus, the examples described herein are not limited to only the recited values, ranges of values, positions, orientations, and/or actions but rather should include reasonably workable deviations.

As used herein, the terms "front" and/or "forward" refer to locations closer to a welding arc, while "rear," "back," "behind," and/or "backward" refers to locations farther from a welding arc.

The term "power" is used throughout this specification for convenience, but also includes related measures such as energy, current, voltage, and enthalpy. For example, controlling "power" may involve controlling voltage, current, energy, and/or enthalpy, and/or controlling based on "power" may involve controlling based on voltage, current, energy, and/or enthalpy.

In accordance with the present invention, the welding torch comprises a contact tip having a rear outer surface, and a gas diffuser configured to receive the rear outer surface within a gas flow path on an interior of the gas diffuser.

In some examples, the gas flow path comprises an axial gas channel configured to direct the gas over the rear outer surface of the contact tip. In some examples, the gas diffuser includes a seat configured to receive the contact tip within the gas diffuser. In some examples, the seat is defined by a plurality of teeth, each tooth includes a shelf, and the contact tip includes a shoulder that interfaces with the shelf of each tooth. In some examples, the gas diffuser comprises a nose that encircles a hollow interior, and the teeth extend from an interior surface of the nose into the hollow interior. In some examples, the gas flow path comprises a plurality of axial gas channels disposed on the interior surface of the nose, between the teeth, and the plurality of axial gas channels are configured to direct the gas over the rear outer surface of the contact tip. In some examples, a diameter of the hollow interior is larger at the axial gas channels than at the teeth. In some examples, the rear outer surface of the contact tip includes a deflector surface that is configured to guide the gas away from an axis of the contact tip. In some examples, the gas diffuser includes a chamfer that is configured to provide clearance for the deflector surface of the contact tip.

In some examples, the gas diffuser further comprises a nose that encircles a hollow interior, and the teeth extend from an interior surface of the nose into the hollow interior. In some examples, the gas flow path comprises a plurality of axial gas channels, and the plurality of axial gas channels are disposed between the teeth. In some examples, a diameter of the hollow interior is larger at the axial gas channels than at the teeth.

In some examples, the gas is routed adjacent the first outer surface via a channel formed within the gas diffuser. In some examples, routing the gas adjacent the second outer surface comprises deflecting the gas radially outward via a deflector surface of the first outer surface, and redirecting the gas radially inward over the second outer surface of the contact tip. In some examples, the gas is redirected radially inward via a tip-retention device. In some examples, the second outer surface of the contact tip is retained within the tip-retention device.

<FIG> shows an example of a welding-type system <NUM>. While the specific welding-type system <NUM> of <FIG> is a gas metal arc welding (GMAW) system, other types of welding-type systems may be used. <FIG> illustrates the welding-type system <NUM> as including a welding-type power source <NUM> coupled to a wire feeder <NUM>, though, in some examples, the wire feeder <NUM> may be removed from the system <NUM>. In the example of <FIG>, the power source <NUM> supplies welding-type power to a torch <NUM> through the wire feeder <NUM>. In some examples, the power source <NUM> may supply welding-type power directly to the torch <NUM> rather than through the wire feeder <NUM>. In the example of <FIG>, the wire feeder <NUM> supplies a wire electrode <NUM> (e.g., solid wire, cored wire, coated wire) to the torch <NUM>. A gas supply <NUM>, which may be integral with or separate from the power source <NUM>, supplies a gas (e.g., CO2, argon) to the torch <NUM>. An operator may engage a trigger <NUM> of the torch <NUM> to initiate an arc <NUM> between the electrode <NUM> and a work piece <NUM>. In some examples, engaging the trigger <NUM> of the torch <NUM> may initiate a different welding-type function, instead of an arc <NUM>.

In some examples, the welding system <NUM> may receive weld settings from the operator via an operator interface <NUM> provided on the power source <NUM> (and/or power source housing). The weld settings may be communicated to control circuitry <NUM> within the power source <NUM> that controls generation of welding-type power for carrying out the desired welding-type operation. In the example of <FIG>, the control circuitry <NUM> is coupled to the power conversion circuitry <NUM>, which may supply the welding-type power (e.g., pulsed waveform) that is applied to the torch <NUM>. In the example of <FIG>, the power conversion circuitry <NUM> is coupled to a source of electrical power as indicated by arrow <NUM>. The source may be a power grid, an engine-driven generator, batteries, fuel cells or other alternative sources.

In some examples, the control circuitry <NUM> may control the current and/or the voltage of the welding-type power supplied to the torch <NUM>. The control circuitry <NUM> may monitor the current and/or voltage of the arc <NUM> based at least in part on one or more sensors <NUM> within the wire feeder <NUM> and/or torch <NUM>. In some examples, a processor <NUM> of the control circuitry <NUM> may determine and/or control the arc length or electrode extension based at least in part on feedback from the sensors <NUM>. The processor <NUM> may determine and/or control the arc length or electrode extension utilizing data (e.g., algorithms, instructions, operating points) stored in a memory <NUM>. The data stored in the memory <NUM> may be received via the operator interface <NUM>, a network connection, or preloaded prior to assembly of the control circuitry <NUM>.

<FIG> is an example welding torch <NUM> that may be used in and/or with the example welding system of <FIG>. The torch <NUM> includes a handle <NUM> attached to a trigger <NUM>. The trigger <NUM> may be actuated to initiate a weld (and/or other welding-type operation). At a rear end <NUM>, the handle <NUM> is coupled to a cable <NUM> where welding consumables (e.g., the electrode <NUM>, the shielding gas, and so forth) are supplied to the weld. Welding consumables generally travel through the rear end <NUM> of the handle <NUM> and exit at a front end <NUM>, which is disposed on the handle <NUM> at an end opposite from the rear end <NUM>.

In the example of <FIG>, the torch <NUM> includes a neck <NUM> (e.g., a gooseneck) extending out of the front end <NUM> of the handle <NUM>. As such, the neck <NUM> is coupled between the handle <NUM> and a welding nozzle <NUM>. As should be noted, when the trigger <NUM> is pressed or actuated, welding wire (e.g., electrode <NUM>) travels through the cable <NUM>, the handle <NUM>, the neck <NUM>, and the welding nozzle <NUM>, so that the welding wire extends out of the front end <NUM> (i.e., torch tip) of the welding nozzle <NUM>. Shielding gas may also travel through the cable <NUM>, the handle <NUM>, the neck <NUM>, and/or the welding nozzle <NUM>.

In the example of <FIG>, the handle <NUM> is secured to the neck <NUM> via fasteners <NUM> and <NUM>, and to the cable <NUM> via fasteners <NUM> and <NUM>. In some examples, the handle <NUM> may be secured to the neck <NUM> using other methods and/or arrangements. The welding nozzle <NUM> is illustrated with a portion of the welding nozzle <NUM> removed to show the electrode <NUM> extending out of a contact tip <NUM> that is disposed within the welding nozzle <NUM>. While the example torch <NUM> illustrated in <FIG> is designed for welding by a human operator, one or more torches designed for use by a robotic welding system may alternatively, or additionally, be used with the welding system of <FIG>. For example, the torch <NUM> may be modified to omit the trigger <NUM>, may be adapted for water cooling, etc..

<FIG> and <FIG> show an example neck and nozzle assembly <NUM> that may be used with the welding torch <NUM> of <FIG>, and/or welding-type system <NUM> of <FIG>. In the example of <FIG> and <FIG>, the neck and nozzle assembly <NUM> includes a nozzle assembly <NUM>, an insulator cap <NUM> (e.g., an electrical insulator cap), a contact tip <NUM>, and a neck assembly <NUM> (e.g., a MIG and/or GMAW welding neck assembly). <FIG> shows an exploded view of the example neck and nozzle assembly <NUM> of <FIG> and <FIG>. As shown in the example of <FIG>, the neck and nozzle assembly <NUM> further includes a gas diffuser <NUM> having an O-ring <NUM>. In the example of <FIG>, the components of the neck and nozzle assembly <NUM> are centered (and/or coaxially arranged) about (and/or around, along, etc.) a longitudinal axis <NUM>.

<FIG> also shows a liner assembly <NUM>, which, in some examples, may be considered part of the neck assembly <NUM> or its own separate assembly. As shown, the liner assembly <NUM> includes a liner coil <NUM> and a liner lock <NUM> attached to a front end of the liner coil <NUM> The liner assembly <NUM> provides a conduit through which the electrode <NUM> may travel from the torch handle <NUM> to the contact tip <NUM>.

<FIG> shows an exploded view of the example neck assembly <NUM>. In the example of <FIG>, the neck assembly <NUM> includes an outer neck armor <NUM>, a neck insulation <NUM> (e.g., electrical neck insulation), a neck inner portion <NUM> (e.g., an electrically conductive neck inner portion), and a liner assembly <NUM> having a liner lock <NUM>. In the example of <FIG>, the outer neck armor <NUM>, neck insulation <NUM>, and neck inner portion <NUM> are generally cylindrical and hollow, with cylindrical bores centered about the axis <NUM> extending through the components.

The neck inner portion <NUM> may be comprised of an electrically conductive material. In the example of <FIG> and <FIG>, the neck inner portion <NUM> includes screw threads <NUM> configured for coupling to complementary interior screw threads <NUM> of the gas diffuser <NUM>. In some examples, the neck inner portion <NUM> and gas diffuser <NUM> may be coupled together using other mechanisms and/or methods, besides screw threads. The neck insulation <NUM> provides electrical (and/or thermal) insulation between the neck inner portion <NUM> and the outer neck armor <NUM>, and may be formed of an electrically insulating material. The outer neck armor <NUM>, neck insulation <NUM>, neck inner portion <NUM>, and liner assembly <NUM> include a bore extending through their centers. The bore is centered along longitudinal axis <NUM>. When the neck assembly <NUM> is fully assembled, the liner coil <NUM> is positioned within the bore of the neck inner portion <NUM>, the neck inner portion <NUM> is positioned within the bore of the neck insulation <NUM>, and the neck insulation <NUM> is positioned within the bore of the outer neck armor <NUM>.

<FIG> shows an exploded view of the example nozzle assembly <NUM>. As shown, the nozzle assembly <NUM> includes a nozzle body <NUM>, a nozzle insulator <NUM> (e.g., a nozzle electrical insulator), and a tip-retention device <NUM> (e.g., a nozzle insert). The tip-retention device <NUM> helps to retain the contact tip <NUM> within the nozzle assembly <NUM>. The nozzle insulator <NUM> provides electrical (and/or thermal) insulation within the nozzle assembly <NUM>, and may be formed of an electrically insulating material. In the example of <FIG>, the nozzle body <NUM> and nozzle insulator <NUM> are generally cylindrical. The nozzle body <NUM>, nozzle insulator <NUM>, and tip-retention device <NUM> include a bore centered about longitudinal axis <NUM>. When the nozzle assembly <NUM> is assembled, the tip-retention device <NUM> is positioned within the nozzle insulator <NUM>, and the nozzle insulator <NUM> is positioned within the nozzle body <NUM>.

<FIG> shows a side view of the contact tip <NUM>. The contact tip <NUM> may be threaded or threadless. If threadless, no tool may be necessary to insert the contact tip <NUM> into the nozzle/gas diffuser assembly, for example. In some examples, the contact tip <NUM> can be secured with the use of a tool. As shown, the contact tip <NUM> includes an internal bore through which an electrode <NUM>, for example, may move and/or extend. The bore may be centered about the longitudinal axis <NUM>.

In the example of <FIG>, the contact tip <NUM> is generally cylindrical. As shown, the contact tip <NUM> includes a front portion <NUM>, a middle portion <NUM>, and a rear portion <NUM>. When assembled into the neck and nozzle assembly <NUM>, the front portion <NUM> of the contact tip <NUM> may be closest to the welding arc <NUM>. In the example of <FIG>, the middle portion <NUM> is directly behind the front portion <NUM>, and is generally tubular (and/or cylindrical). A portion of the middle portion <NUM> may be positioned within the tip-retention device <NUM> and/or nozzle insulator <NUM> when the contact tip <NUM> is assembled into the neck and nozzle assembly <NUM>.

In the example of <FIG>, the rear portion <NUM> of the contact tip <NUM> is positioned directly behind the middle portion <NUM>. In some examples, the rear portion <NUM> may be positioned within the gas diffuser <NUM> and/or tip-retention device <NUM> when the contact tip <NUM> is assembled into the neck and nozzle assembly <NUM>. As shown, the rear portion <NUM> comprises a forward taper <NUM>, a deflector portion <NUM> (and/or rear taper), and a stepped profile <NUM>.

In the example of <FIG>, the forward taper <NUM> expands an outer diameter of the contact tip <NUM> as it extends rearward from the middle portion <NUM>. In some examples, the forward taper <NUM> may be configured to interface with the nozzle assembly <NUM> (e.g., with a taper <NUM> of a tip-retention wall <NUM> of the tip-retention device <NUM> of the nozzle assembly <NUM>) when the contact tip <NUM> is assembled into the neck and nozzle assembly <NUM>. The forward taper <NUM> may be, for example, a forward-facing locking taper.

In the example of <FIG>, the deflector surface <NUM> (and/or rear taper) is positioned to the rear of the forward taper <NUM>. The contact tip <NUM> includes a connecting portion <NUM>, extending generally parallel to the axis <NUM>, between the forward taper <NUM> and deflector surface <NUM>. The deflector surface <NUM> reduces the outer diameter of the contact tip <NUM> as it extends rearward from the connecting portion <NUM>. In some examples, the deflector surface <NUM> may be configured to guide gas flow when the contact tip <NUM> is assembled into the neck and nozzle assembly <NUM>.

In the example of <FIG>, the contact tip <NUM> also includes a profile <NUM> (e.g., a stepped profile or other type of profile) disposed at the rear of the contact tip <NUM>, directly behind the deflector surface <NUM>. As shown in the example of <FIG>, the profile <NUM> includes an L shaped shoulder <NUM> (and/or step) formed at a right angle between a first portion <NUM> and second portion <NUM> of the profile <NUM>. In a three-dimensional view, the shoulder <NUM> may appear more annular. The shoulder <NUM> is positioned at an orthogonal transition of the contact tip <NUM>, where the outer diameter of the contact tip <NUM> is further reduced.

In some examples, the profile <NUM> may be configured to interface with the gas diffuser <NUM>. For example, the profile <NUM> (and/or shoulder <NUM> of the profile <NUM>) may interface with a seat of the gas diffuser <NUM> to receive the contact tip <NUM> within the gas diffuser <NUM> when the contact tip <NUM> is assembled into the neck and nozzle assembly <NUM>. In some examples, the profile <NUM> may be configured to align with the liner assembly <NUM>, liner lock <NUM>, and/or liner coil <NUM> when the contact tip <NUM> is assembled into the neck and nozzle assembly <NUM>. In some examples, the deflector surface <NUM> and the profile <NUM> form a turned down portion of the rear outer surface of the contact tip <NUM> that provides surface area for cooling. In some examples, the shape of the deflector surface <NUM> and/or the profile <NUM> may be configured to maximize or increase a cooling effect on the contact tip <NUM> as shielding gas flows over the rear outer surface of the contact tip <NUM>.

<FIG> shows a front perspective view of the liner lock <NUM>. The liner lock <NUM> may be attached to an end of the liner coil <NUM>. In some examples, the liner lock <NUM> may be larger in diameter than an internal bore of the neck inner portion <NUM> such that the liner lock <NUM> prevents the liner assembly <NUM> from retracting (e.g., axially toward a rear portion of the welding torch <NUM>) into the neck inner portion <NUM>. In some examples, the gas diffuser <NUM> may be configured internally to interact with the liner lock <NUM>, liner coil <NUM>, and/or liner assembly <NUM>, such that the liner coil <NUM> may not abut, reside within, nor be in any physical contact with the rear end of the contact tip <NUM>. As such, the installation and removal of the contact tip <NUM> may be made easier in that the liner assembly <NUM> may not exert any axial or counter-rotational forces against the contact tip <NUM>. In some examples, the gas diffuser <NUM> may also be configured internally to interact with the liner lock <NUM> such that the liner assembly <NUM> maintains better concentricity between the liner assembly <NUM> and the contact tip <NUM>. Indeed, in some examples, the liner lock <NUM> may be integral to the gas diffuser <NUM>. In other words, the features of the liner lock <NUM>, as described herein, may be part of the gas diffuser <NUM> in examples where the liner lock <NUM> and the gas diffuser <NUM> are integrated into a single component.

In the example of <FIG>, the liner lock <NUM> includes a main body <NUM> and a nose <NUM>. Both the nose <NUM> and main body <NUM> are generally cylindrical. When assembled into the neck and nozzle assembly <NUM>, the main body <NUM> and/or nose may be centered about longitudinal axis <NUM>. As shown, the outer diameter of the main body <NUM> is larger than the outer diameter of the nose <NUM>. A bore <NUM> (e.g., centered about longitudinal axis <NUM>) extends through the nose <NUM> (and/or main body <NUM>). In the example of <FIG>, the liner lock <NUM> includes a liner lock shoulder <NUM> formed at a generally orthogonal transition between the main body <NUM> and the nose <NUM>. In some examples, the liner lock shoulder <NUM> may be configured to interact with (and/or abut, interface with, engage with, etc.) a complementary shoulder <NUM> of the gas diffuser <NUM>, when the liner lock <NUM> is assembled into the neck and nozzle assembly <NUM>. In the example of <FIG>, the main body <NUM> includes several ports <NUM> ringed around the nose <NUM>. When the liner lock <NUM> is assembled into the neck and nozzle assembly <NUM>, the ports <NUM> may provide a passageway through which gas may flow (e.g., between the contact tip <NUM> and the gas diffuser <NUM>).

<FIG> and <FIG> show front and rear perspective views of the tip-retention device <NUM>. In some examples, the tip-retention device <NUM> may be configured to retain the contact tip <NUM> within the nozzle assembly <NUM>. In some examples, the tip-retention device <NUM> may be, for example, a nozzle insert or addition that is crimped into or outside of the nozzle body <NUM>. In some examples, the tip-retention device <NUM> may be an integral part of the nozzle body <NUM> and/or other portions of the nozzle assembly <NUM>.

As shown, the tip-retention device <NUM> is approximately cylindrical, though in some examples the tip-retention device <NUM> may be shaped differently to accommodate the shape of the nozzle assembly <NUM>. In the example of <FIG> and <FIG>, the tip-retention device <NUM> includes an approximately cylindrical sidewall <NUM>. The sidewall <NUM> surrounds a generally hollow interior. The outer diameter of the sidewall <NUM> may be sized so as to frictionally engage with the nozzle insulator <NUM> when the tip-retention device <NUM> is within the nozzle insulator <NUM>. As shown in the example of <FIG> and <FIG>, the interior of the sidewall <NUM> may be formed with threads <NUM> configured to engage (and/or couple) with complementary threads <NUM> of the gas diffuser <NUM>. In some examples, the tip-retention device <NUM> may include alternative and/or additional mechanisms and/or surfaces for engagement with the gas diffuser <NUM>.

A tip-retention wall <NUM> extends from the sidewall <NUM> into the interior of the tip-retention device <NUM>, proximate a leading edge <NUM> of the tip-retention device <NUM>. The tip-retention wall <NUM> includes a bore <NUM> configured to fit the contact tip <NUM>. The tip-retention wall <NUM> further includes a locking taper <NUM> on the portion of the tip-retention wall <NUM> immediately surrounding the bore <NUM>. The locking taper <NUM> is configured to engage a matching forward locking taper <NUM> (e.g., a forward-facing locking taper) of the contact tip <NUM>. More particularly, the locking taper <NUM> of the tip-retention wall <NUM> may be configured to abut and/or engage the locking taper <NUM> of the contact tip <NUM>, so as to retain the contact tip <NUM> within the bore <NUM> of the tip-retention device <NUM>. In some examples, the engagement may also maintain concentricity and conductivity. Because of the locking taper <NUM>, the bore <NUM> has a smaller circumference (and/or radius, diameter, size, etc.) on one side of the tip-retention wall <NUM> than on the other side. More particularly, the bore <NUM> has a smaller circumference (and/or radius, diameter, size, etc.) on the side of the tip-retention wall <NUM> closest to the leading edge <NUM> of the tip-retention device <NUM>. The bore <NUM> has a larger circumference (and/or radius, diameter, size, etc.) on the opposite side of the tip-retention wall <NUM>, closer to a rear edge <NUM> of the tip-retention device <NUM>.

In the examples of <FIG> and <FIG>, the tip-retention device <NUM> further includes gas holes <NUM> on front and rear sides of the tip-retention wall <NUM>. As shown, the gas holes <NUM> are positioned on the sidewall <NUM>, radially around the tip-retention device <NUM>. The gas holes <NUM> are disposed in/on a channel portion <NUM> of the sidewall <NUM> that has a smaller outer diameter than the majority of the sidewall <NUM>, so as to provide room for shielding gas to flow between the tip-retention device <NUM> and the nozzle insulator <NUM> (and/or other portions of the nozzle assembly <NUM>) when the tip-retention device <NUM> is assembled with the neck and nozzle assembly <NUM>. In the example of <FIG> and <FIG>, the gas holes <NUM> are approximately circular (and/or oval, elliptical, etc.). The gas holes <NUM> may be configured to provide a route and/or path for shielding gas to flow through the sidewalls <NUM> (and/or channel portion <NUM>) and around the tip-retention wall <NUM>.

The tip-retention device <NUM> may be configured to provide clearance for gas flow by providing gas holes <NUM> through its sidewall <NUM> to direct gas inwardly towards the contact tip <NUM>. More particularly, gas flow from the gas diffuser <NUM> may be directed radially outward by the tip-retention wall <NUM> (and/or contact tip <NUM> retained by the tip-retention wall <NUM>). The outwardly directed gas may flow through gas holes <NUM> on the rear side of the tip-retention wall <NUM>, and through the channel portion <NUM>. The nozzle insulator <NUM> and/or leading edge <NUM> may then direct the shielding gas radially inward through the gas holes <NUM> on the front side of the tip-retention wall <NUM>, towards the contact tip <NUM>. The inward gas flow directed at the contact tip <NUM> may provide a cooling effect on the contact tip <NUM>. The radially facing gas holes <NUM> (e.g., radial channels) may further resist spatter collection in comparison to forward-facing gas holes (e.g., axial channels).

In some examples, other example tip-retention devices may be used, such as those described in at least <CIT>, which is owned by the assignee of this application, and which is incorporated herein by reference.

<FIG> show various views of the gas diffuser <NUM>. The gas diffuser <NUM> may be electrically conductive. As shown in the examples of <FIG>, the gas diffuser <NUM> is generally hollow, and includes a generally cylindrical base <NUM> and a nose <NUM> connected to the base <NUM>. The base <NUM> is approximately centered about longitudinal axis <NUM> when assembled with the neck and nozzle assembly <NUM>. Both the base <NUM> and the nose <NUM> encircle the hollow interior. The diameter of the hollow interior is generally larger within the base <NUM> than within the nose <NUM>.

As shown, an exterior surface of the base <NUM> includes an annular crevice <NUM> configured to receive the O-ring <NUM>. The O-ring <NUM> may be configured to create a gas seal between the gas diffuser <NUM> and the nozzle insulator <NUM> (and/or some other part of the nozzle assembly <NUM>) when the O-ring <NUM> and gas diffuser <NUM> are assembled into the neck and nozzle assembly <NUM>. In the examples of <FIG>, an interior surface of the base <NUM> includes a diffuser shoulder <NUM> configured to abut (and/or engage, interface, etc.) the liner lock shoulder <NUM>, so as to prevent the liner lock <NUM> from moving further forward within the gas diffuser <NUM> when the gas diffuser <NUM> is assembled with the neck and nozzle assembly <NUM>. When full assembled, the nose <NUM> of the liner lock <NUM> may extend into the hollow interior of the nose <NUM> of the gas diffuser <NUM>.

In the examples of <FIG>, the base <NUM> of the gas diffuser <NUM> includes outer threads <NUM> formed on the exterior surface of the base <NUM>, and inner threads <NUM> formed on the interior surface of the base <NUM>. The outer threads <NUM> may be configured to mate with (and/or engage, interface with, couple to, etc.) complementary internal threads <NUM> of the tip-retention device <NUM>. The interior threads <NUM> may be configured to mate with (and/or engage, interface with, couple to, etc.) complementary external threads <NUM> of the neck assembly <NUM>. In the example of <FIG>, the nose <NUM> of the gas diffuser <NUM> includes wrench flats <NUM> that may be used, if necessary, to tighten the gas diffuser <NUM> to the neck assembly <NUM> via internal threads <NUM> of the gas diffuser <NUM> and/or mating external threads <NUM> of the neck assembly <NUM>. In some examples, the gas diffuser <NUM>, tip-retention device <NUM>, and/or neck assembly <NUM> may be coupled together using other mechanisms and/or methods besides screw threads (e.g. friction fit).

In the examples of <FIG>, the gas diffuser <NUM> includes a front rim <NUM> at the axial end of its nose <NUM>. A chamfered surface <NUM> extends inwardly from the front rim <NUM> towards the hollow interior of the gas diffuser <NUM>. In some examples, the chamfered surface <NUM> may provide clearance for the deflector surface <NUM> on the contact tip <NUM>. The chamfered surface <NUM> may also narrow a diameter of the hollow interior of the gas diffuser <NUM> within the nose <NUM>. As shown, the chamfered surface <NUM> leads to ledges <NUM>, which connect to teeth <NUM> through shelves <NUM>.

In the examples of <FIG>, a plurality of teeth <NUM> extend radially inwards from the interior surface of the nose <NUM> into the hollow interior of the gas diffuser <NUM>. Each tooth <NUM> includes a shelf <NUM> (and/or shoulder), formed at an orthogonal transition between the tooth <NUM> and a ledge <NUM>. The shelf <NUM> may abut (and/or engage, interface with, press against, etc.) the shoulder <NUM> at the rear stepped profile <NUM> of the contact tip <NUM> when the contact tip <NUM> and gas diffuser <NUM> are assembled into the neck and nozzle assembly <NUM>. The ledge <NUM>, tooth <NUM>, and/or shelf <NUM> may therefore comprise a complementary stepped profile to the stepped profile <NUM> of the contact tip <NUM>, and/or a seat configured to receive the contact tip <NUM> when the contact tip <NUM> and gas diffuser <NUM> are assembled into the neck and nozzle assembly <NUM>. When the contact tip <NUM> and gas diffuser <NUM> are assembled into the neck and nozzle assembly <NUM>, the contact tip <NUM> may be retained within the gas diffuser <NUM>, tip-retention device <NUM>, and/or nozzle assembly <NUM> may a compressive force between the seat of the gas diffuser <NUM> and the tip-retention wall <NUM> (and/or taper <NUM> of the tip-retention wall <NUM>) of the tip-retention device <NUM>.

In the examples of <FIG>, the gas diffuser <NUM> further includes a plurality of axial gas channels <NUM> ringed around the interior surface of the nose <NUM>. As shown, the gas channels <NUM> extend approximately parallel to the longitudinal axis <NUM>. In the examples of <FIG>, each gas channel <NUM> is positioned between two teeth <NUM>, in a circumferential (and/or arcuate) direction. The interior diameter of the gas diffuser <NUM> (and/or diameter of hollow interior) is larger at the gas channels <NUM> than at the teeth <NUM> and/or ledges <NUM>, and/or the chamfered surface <NUM>. The gas channels <NUM> extend axially from approximately the front rim <NUM> past the shelves <NUM> of the teeth <NUM>. Thus, the gas channels <NUM> provide conduits (and/or passages) through which gas may flow past (and/or over, across, etc.) the contact tip <NUM> when the contact tip <NUM> is received in the of the gas diffuser <NUM>. Further, the liner assembly <NUM> may prevent gas flowing through the gas diffuser <NUM> and/or channels <NUM> from flowing into the interior of the contact tip <NUM> with the electrode <NUM>. Thus, the gas channels <NUM> may be configured to direct (and/or guide, steer, etc.) shielding gas over the outside surface (e.g., profile <NUM>, deflector surface <NUM>, etc.) of the contact tip <NUM> while the contact tip <NUM> is retained in the seat, which may help to cool the contact tip <NUM>, reduce wear and tear due to high temperatures, and/or extend the life of the contact tip <NUM>.

<FIG> shows a perspective view of the fully assembled example neck and nozzle assembly <NUM>, with a portion cutaway. <FIG> show cross-sectional views of the example neck and nozzle assembly <NUM>. <FIG> shows a cross-sectional view through the teeth <NUM> of the gas diffuser <NUM> (similar to <FIG>). <FIG> shows a cross-sectional view through the gas channels <NUM> in the gas diffuser <NUM> (similar to <FIG>). <FIG> shows the cross-sectional view of <FIG> with an example gas flow <NUM>.

In the examples of <FIG>, the tip-retention device <NUM> and gas diffuser <NUM> cooperate to retain the contact tip <NUM> within the neck and nozzle assembly <NUM>. More particularly, the tip-retention device <NUM> and gas diffuser <NUM> interface (and/or engage) with the rear portion <NUM> of the contact tip <NUM> to retain the contact tip <NUM> within the neck and nozzle assembly <NUM>. More precisely, the forward taper <NUM> of the contact tip <NUM> interfaces (e.g., engages) with the taper <NUM> of the tip-retention wall <NUM> of the tip-retention device <NUM>, and the stepped profile <NUM> and/or shoulder <NUM> of the contact tip <NUM> interfaces (and/or engages) with the shelves <NUM> of the teeth <NUM> of the gas diffuser <NUM>. The contact tip <NUM> is locked in place between the tip-retention wall <NUM> of the tip-retention device <NUM> and the seat of the gas diffuser <NUM>. In some examples, the contact tip <NUM> does not need its own threads to be locked in place. In some examples, the rear end of the contact tip <NUM> rests against the liner assembly <NUM>.

In the examples of <FIG>, the liner lock <NUM> is disposed within the gas diffuser <NUM>. The liner lock shoulder <NUM> abuts the interior shoulder <NUM> of the gas diffuser <NUM>, which helps to position and/or align the liner assembly <NUM> (and/or an electrode <NUM> moving within the liner assembly <NUM>) with the interior bore of the contact tip <NUM>. The screw threads <NUM> of the gas diffuser <NUM> are engaged with the screw threads <NUM> of the tip-retention device <NUM> to couple the tip-retention device <NUM> to the gas diffuser <NUM>. The tip-retention device <NUM> retained within the nozzle insulator <NUM> with a friction fit. The gas diffuser <NUM> is further coupled to the neck assembly <NUM> via interior screw threads <NUM> of the gas diffuser <NUM> engaging with outer screw threads <NUM> of the neck assembly <NUM>.

In operation, gas flow <NUM> (and/or a convection current) may flow through the neck and nozzle assembly <NUM>. <FIG> shows example gas flow through a cross-sectional view of an example of assembled portions of the welding torch according to the present disclosure. Referring to <FIG>, the gas flow <NUM> (e.g., shielding gas) moves through the neck assembly <NUM> to the gas diffuser <NUM>. More particularly, the gas flow <NUM> moves between the liner coil <NUM> and the neck inner portion <NUM>, generally parallel to the longitudinal axis <NUM>. After exiting the neck inner portion <NUM>, the gas flow <NUM> moves through the ports <NUM> in the liner lock <NUM> to move from the neck assembly <NUM> to the gas diffuser <NUM>. The gas flow <NUM> then proceeds through the channels <NUM> and across (and/or along, over, etc.) the rear portion <NUM> of the contact tip <NUM>. In particular, the gas passes over the profile <NUM> and the deflector surface <NUM> of the contact tip <NUM> and cools the contact tip <NUM>. The deflector surface <NUM> and/or the profile <NUM> may be structurally designed to cool the contact tip <NUM> the appropriate amount for particular applications (e.g., welding, cladding, cutting, etc.) and/or for particular size parameters or tolerances. By cooling the contact tip <NUM> during operations, the life of the contact tip <NUM> can be extended.

The deflector surface <NUM> is configured not only to cool the contact tip <NUM>, but also to deflect the gas in a general direction away from the axis of the contact tip <NUM>. The deflector surface <NUM> may be configured so as to direct gas flow in such a way that the gas flow remains laminar, rather than becoming turbulent. In the example of <FIG>, the gas flow <NUM> is directed radially outward (approximately orthogonal to the axis <NUM>) by the deflector <NUM> of the contact tip <NUM> and the tip-retention wall <NUM>, toward the gas holes <NUM> on the rear side of the tip-retention wall <NUM>. The gas flow moves through the gas holes <NUM>, and is redirected by the nozzle insulator <NUM> towards the front end <NUM>, along a path generally parallel with the axis <NUM>. The leading edge <NUM> of the tip-retention device <NUM> then directs the gas flow <NUM> radially inward through the gas holes <NUM> on the front side of the tip-retention wall <NUM>. Once through the gas holes <NUM>, the gas flow <NUM> again flows across the contact tip <NUM>, providing more cooling flow. Finally, the gas flow <NUM> proceeds out through the front end <NUM> of the nozzle assembly <NUM>.

Claim 1:
A welding torch (<NUM>), comprising:
a contact tip (<NUM>) having a rear outer surface (<NUM>, <NUM>); and
a gas diffuser (<NUM>) including a seat defined by a plurality of teeth (<NUM>) and configured to receive the rear outer surface (<NUM>, <NUM>) within a gas flow path on an interior of the gas diffuser (<NUM>),
characterized in that the rear outer surface (<NUM>, <NUM>) of said contact tip (<NUM>) includes an L shaped annular shoulder (<NUM>) formed at a right angle and positioned at an orthogonal transition of the contact tip (<NUM>) where the outer diameter of the contact tip (<NUM>) is reduced, and each tooth (<NUM>) of said seat includes a shelf (<NUM>) that interfaces with the annular shoulder (<NUM>) of the contact tip (<NUM>).