Abstract: A welding contact tip and diffuser assembly for use in a welding apparatus. The assembly includes an electrically conductive contact tip having a tapered exterior surface, a diffuser having a cavity with a tapered interior surface, and a releasable connection for holding the contact tip in the diffuser. The connection includes at least one detent element in either the diffuser or the contact tip, at least one recess forming a ramp in the other of the diffuser or contact tip, and at least one spring. The spring biases the detent element into the recess and against the ramp to generate an axial force against the ramp. The axial force tends to urge the tapered surfaces of the contact tip and diffuser into contact with one another.

Abstract: A welding torch (2) for use in gas metal arc welding, including a neck portion (4), a diffuser (6) at a first end (8) of the neck portion (4), a contact tip (10) which extends from the diffuser (6), and connector means (12) which is at a second end (14) of the neck portion (4) and which is for connecting the neck portion (4) to a power cable assembly; the neck portion (4) including an electrical conductor (16) and a longitudinally extending passageway (18); electrical current transfer from the electrical conductor (16) to the contact tip (10) being effected using first and second longitudinally separated contact areas (22, 24) on the contact tip (10); and the welding torch (2) including a gas chamber (30) which is positioned longitudinally between the two contact areas (22, 24) and radially between the contact tip (10) and the diffuser (6).

Abstract: A welding torch (2) for use in gas metal arc welding, which welding torch (2) comprises a neck portion (4), a diffuser (6) at a first end (8) of the neck portion (4), a contact tip (10) which extends from the diffuser (6), connector means (12) which is at a second end of the neck portion (4) and which is for connecting the neck portion (4) to a power cable assembly (16), and a trigger switch (114): the power cable assembly being such that it supplies electricity and gas to the welding torch (2) with the gas being for protecting welds from atmospheric contamination as the welds are made using the welding torch (2); the neck portion (4) being such that it comprises an electrical conductor (20) and a passageway (22) for the gas; the neck portion (4) being such that it comprises insulation (26) in the form of an overmoulding of a plastics material, the overmoulding being such that it also provides rigidity and impact strength to the neck portion (4); the trigger switch (114) being a snap fit in position in a sock

Abstract: A gas diffuser for a welding gun in which atmospheric air in the interior of the liner is substantially prevented from entering the contact tip hole. The gas diffuser comprises a cradle having a hole and a section of a concave surface disposed around a periphery of the hole, and an outer peripheral body having a first axial bore on one side of the cradle and a second axial bore on the other side of the cradle. The outer peripheral body comprises one or more generally axial slots, each slot having one end that opens into the first axial bore and another end that opens into the second axial bore. Each slot is open to the exterior of the diffuser along its length and is disposed radially outward of the cradle. The first and second axial bores communicate via the hole in the cradle and via the slots.

Abstract: A welding gun having a removable end portion. The end portion may be adapted to direct gas from the welding gun. The end portion may be conical-shaped. The end portion may be removed without tools. The end portion also may be adapted to be secured to and/or removed from the welding gun in a linear movement. A method of assembling a welding gun. The method may comprise urging a nozzle end member and a nozzle body into engagement to secure the nozzle end member to the nozzle body.

Abstract: A MIG welding gun contact tip has a cylindrical section with a predetermined outer diameter adjacent one end, and frusto-conical surface adjacent the other end. Threads are rolled from the cylindrical section outer diameter between the cylindrical section and the frusto-conical surface. The threads major diameter is larger than the cylindrical section outer diameter, and the threads minor diameter is less than the cylindrical section outer diameter. In a preferred embodiment, the cylindrical section outer diameter is approximately 0.350 inches, the threads have a major diameter of approximately 0.375 inches, and the threads are stub acme threads with a pitch of 14 threads per inch. The contact tip is assembled to a diffuser having mating threads and a frusto-conical surface that engages the contact tip frusto-conical surface when the contact tip has been turned a single turn into the diffuser.

Abstract: A welding torch (2) for use in gas metal arc welding, comprising a neck portion (4), a diffuser (6) at a first end (8) of the neck portion (4), a contact tip (10) which extends from the diffuser (6), and connector means (12) which is at a second end (14) of the neck portion (4) and which is for connecting the neck portion (4) to a power cable assembly; the neck portion (4) comprising an electrical conductor (16) and a longitudinally extending passageway (18); electrical current transfer from the electrical conductor (16) to the contact tip (10) being effected using first and second longitudinally separated contact areas (22, 24) on the contact tip (10); and the welding torch (2) including a gas chamber (30) which is positioned longitudinally between the two contact areas (22, 24) and radially between the contact tip (10) and the diffuser (6).

Abstract: Gas shielded arc welding is performed using gas nozzle 10 which includes a straight portion 14 that permits the shielding gas flows from orifices 18 to flow parallel to the axial direction and a constricted portion 20 continuous from the straight portion 14 that constricts the gas flows from the straight portion 14 as they travel toward the distal end and the nozzle 10 satisfies the following relations (1) and (2): 1.5≦(Dp/Do)≦2.5  (1) 1.0≦(L/Dp)  (2) where Dp is the inside diameter of the straight portion 14, Do is the inside diameter of the distal gas outlet of the constricted portion 20, and L is the axial length of the constricted portion 20.

Abstract: A welding torch (2) for use in gas metal arc welding, which welding torch (2) comprises a neck portion (4), a diffuser at a first end (6) of the neck portion (4), a contact tip which extends from the diffuser, and connector means which is at a second end (8) of the neck portion (4) and which is for connecting the neck portion (4) to a power cable assembly: the power cable assembly being such that it supplies electricity and gas to the welding torch (2) with the gas being for protecting welds from atmospheric contamination as the welds are made using the welding torch (2); the neck portion (4) being such that it comprises an electrical conductor (10) and a passageway for the gas; and the neck portion (4) being such that it comprises insulation (12) in the form of an overmoulding of a plastics material, the overmoulding being such that it also provides rigidity and impact strength to the neck portion (4).

Abstract: A MIG welding gun has a diffuser with an external thread and a frusto-conical back ramp. A nozzle assembly includes an insert with a back ramp and a thread that mates with the diffuser thread. The threads of the diffuser and insert have respective ramps that mate. A single turn of the nozzle assembly on the diffuser causes simultaneous engagement of the insert and diffuser back ramps and of the insert and diffuser thread ramps. Such engagement centers the nozzle to be concentric with the diffuser and also produces a wedging action that retains the nozzle assembly on the diffuser until a relatively substantial reverse torque is applied to the nozzle assembly. The nozzle front end has a narrow annulus, which reduces the amount of radiant heat from the welding arc that reaches the nozzle.

Abstract: A MIG welding gun has a diffuser with an external thread and a frusto-conical back ramp. A nozzle assembly includes an insert with a back ramp and a thread that mates with the diffuser thread. The threads of the diffuser and insert have respective ramps that mate. A single turn of the nozzle assembly on the diffuser causes simultaneous engagement of the insert and diffuser back ramps and of the insert and diffuser thread ramps. Such engagement centers the nozzle to be concentric with the diffuser and also produces a wedging action that retains the nozzle assembly on the diffuser until a relatively substantial reverse torque is applied to the nozzle assembly. The nozzle front end has a narrow annulus, which reduces the amount of radiant heat from the welding arc that reaches the nozzle.

Abstract: A MIG welding gun has a diffuser with an external thread and a frusto-conical back ramp. A nozzle assembly includes an insert with a back ramp and a thread that mates with the diffuser thread. The threads of the diffuser and insert have respective ramps that mate. A single turn of the nozzle assembly on the diffuser causes simultaneous engagement of the insert and diffuser back ramps and of the insert and diffuser thread ramps. Such engagement centers the nozzle to be concentric with the diffuser and also produces a wedging action that retains the nozzle assembly on the diffuser until a relatively substantial reverse torque is applied to the nozzle assembly. The nozzle front end has a narrow annulus, which reduces the amount of radiant heat from the welding arc that reaches the nozzle.

Abstract: A MIG welding gun has a diffuser with an external thread and a frusto-conical back ramp. A nozzle assembly includes an insert with a back ramp and a thread that mates with the diffuser thread. The threads of the diffuser and insert have respective ramps that mate. A single turn of the nozzle assembly on the diffuser causes simultaneous engagement of the insert and diffuser back ramps and of the insert and diffuser thread ramps. Such engagement centers the nozzle to be concentric with the diffuser and also produces a wedging action that retains the nozzle assembly on the diffuser until a relatively substantial reverse torque is applied to the nozzle assembly. The nozzle front end has a narrow annulus, which reduces the amount of radiant heat from the welding arc that reaches the nozzle.

Abstract: A welding gun contact tip which seats within a retaining member and in two different seating locations relative to the contact member. The contact tip includes an interwoven-double-start thread having two thread cuts which start 180 degrees from one another as measured around the circumference of the contact tip. Additionally, the retaining member includes an interwoven-double-start thread having two thread cuts which start 180 degrees from one another as measured around the circumference of the contact tip. Because of the configuration of the interwoven-double-start threads, the two seating locations of the contact tip are 180 degrees apart thereby enabling the contact tip to be used twice as long as a conventional contact tip which includes a single cut thread. Further, the contact tip and retaining member include mating frustum surfaces which are configured and dimensioned so that the contact tip seats within the retaining member with less than one turn of the contact tip relative to the retaining member.