Control assembly for a welding gun

A welding gun includes a control switch combined with a trigger. The control switch features a slide movable to at least first and second positions. In an operating mode, the control switch switches between two differing sets of welding parameters in the first and second positions. In another operating mode, the control switch operates a safety lock-out, allowing activation of the welding gun by the trigger in one position and preventing activation in the other position. For operator convenience, the control switch may be positioned to slide transversely relative to the wire passageway of the weld gun with which the trigger is generally aligned.

TECHNICAL FIELD

This invention relates to welding systems, and more particularly to a procedure controlling switch for a welding gun.

BACKGROUND OF THE INVENTION

Welding is used in various manufacturing and construction applications to join various metal pieces together to form a unitary piece. An arc welding system typically includes an electric power supply coupled to a welding gun that houses an electrode that is located in the handle. The electrode completes an electrical circuit with a source of power when the electrode is placed against a piece of metal to be welded. The contact between the electrode and the piece of metal produces an electric arc between the electrode and the metal piece. The heat of the electric arc is concentrated on the metal piece, or pieces, to be joined, thereby melting the metal piece(s). A filler material is added to the molten metal, which subsequently cools and solidifies, joining the metal pieces together.

Metal Inert Gas (MIG) welding is one type of arc welding. MIG welding is also referred to as “wire feed” or Gas Metal Arc Welding (GMAW). In MIG welding a metal wire is used as the electrode to produce the arc. The wire is shielded by an inert gas and the metal wire acts as the filler for the weld. The inert gas is used to shield the electric arc from contaminants and gases that may react with the weld. Typically, the wire and gas are fed through a hand-held welding gun. The wire and gas are fed to the welding gun from a welding system having a wire feeder, a power source and a source of gas.

FIG. 1illustrates a typical prior art welding gun10. The welding gun typically includes a switch or trigger12that is coupled to the rest of the system. The welding gun includes a modular switch assembly14that is configured to be actuated by an operator's index finger. The switching mechanism inside the trigger is a conventional open/close contact mechanical switch, having a plurality of mechanical connections and moving parts. When the trigger is actuated, gas and wire are fed through the handle16and the curved delivery tube and nozzle18, and power is applied to the welding wire, not shown.

Other types of welding, such as submerged arc welding, utilize wire guns that include switches or triggers. In submerged arc welding, a trigger is actuated to feed flux and wire through the welding gun. The triggers and switches of typical prior art welding guns include mechanical connections and moving parts, such as springs, stems or the like.

Various welding guns also include a trigger locking mechanism so that an operator does not have to constantly press the trigger in order to maintain activation. The locking mechanism is configured to allow for a quick release. Thus, when the operator is finished welding, the operator simply engages the quick release to finish activation.

SUMMARY OF THE INVENTION

The present invention provides a welding gun including a control switch that features a slide movable to at least first and second control positions. The control switch may be connected in various ways to control an operation of the welding gun upon activation of the switch or to provide a safety function that controls activation of a trigger of the welding gun itself.

In one operating mode, the control switch is connected to operate as a dual procedure switch that remotely switches the welding system between two sets of welding parameters. This may be accomplished by transverse movement of the slide relative to the orientation of the welding gun handle, which selects between the welding parameters available in the first and second switch positions for carrying out welding when the trigger is operated.

In another operating mode, the control switch may be wired as a safety lock-out, allowing activation of the gun by the trigger in one position and preventing activation of the gun in the other position. For operator control convenience, the control switch may be positioned to slide transversely relative to the handle and the wire passageway of the weld gun with which the trigger is generally aligned.

These and other features and advantages of the invention will be more fully understood from the following detailed description of the invention taken together with the accompanying drawings.

DETAILED DESCRIPTION OF THE INVENTION

Referring now toFIGS. 2 and 3of the drawings, numeral20generally indicates a welding gun according to the present invention. Welding gun20may be arranged to be held in various positions for welding of metal workpieces. Each figure shows a welding gun20having a handle22, a gooseneck26and a contact tip28at a distal end30of the gooseneck. A cap32retains the gooseneck26on the handle but may be loosened to allow rotation thereof to any direction convenient for welding of various workpieces.

Each figure shows an assembly34mounted near the front of the handle22. Each assembly34includes a switch body35carrying a36with an actuator lever38, generally aligned with the handle22, and a control switch40including (seeFIGS. 4-6) a slide42retained by a cover44and forming a switch transversely movable in the switch body35.

InFIG. 2, the assembly34is mounted on the lower side of the handle22with the gooseneck26angled down. A gloved hand of an operator is shown holding the handle16in an upright position to operate the trigger and control switch40on the lower side of the handle22.

InFIG. 3, the same welding gun20is shown with the handle22inverted so that the assembly34is on the top. The gooseneck26has been again turned down by loosening the retaining cap32and rotating the gooseneck relative to the handle. In this position, the gloved hand is again in position to operate the trigger and control switch34now being held on top of the handle22.

The foregoing is exemplary of the arrangements which are provided by the welding gun20having a handle22which may be connected with a source of power and to a welding wire feed and a supply of inert gas, not shown, for MIG or submerged arc welding.

Referring toFIGS. 2-6assembly34may be of modular construction mounted on the handle22. Assembly34includes a switch body35enclosing a trigger36with a positioning lever38that may be positioned to be easily actuated by an index finger of an operator. In accordance with the invention, the control switch40may be mounted on the switch body35or on the handle22adjacent to the switch body35. The control switch40is operatively connected with the trigger36and includes a slide42movable between first and second positions but shown in the first position. The slide movement to first and second positions is indicated by arrows46,48, respectively, inFIGS. 5 and 6. In these positions, the control switch40may be operative to control, respectively, the function or activation of the operator actuated trigger36of the hand-held welding gun20.

The welding gun20may be operable for MIG welding, submerged-arc welding or other suitable welding operations. The control switch40may be connected in a first operating mode as a dual procedure switch operative to remotely switch the welding system between two sets of welding parameters. In a second operating mode, the control switch40may be wired in series with a main trigger on/off circuit, which serves as a safety lock-out to prevent unintended activation of the trigger function. Such a safety is an important feature in industrial applications such as shipyards.

As indicated, the control switch40includes a slide42positioned to move laterally within the cover44of the switch body35wherein the slide42is moved generally transverse to the direction of the wire passageway in the handle22of an associated welding gun20. The control switch40may be of simple construction having the slide42, carrying, for example, a bridging contact, not shown, movable between dual connector contacts in laterally spaced positions in the control switch40, with detents, not shown, to maintain the switch in either selected position. If desired, the control switch40could be positioned in any desired orientation so that the slide42could move in other directions than transverse to the axis of the wire passageway.

Thus, the present invention provides a sliding control switch having simple construction and which may be positioned for sliding in a transverse or other desired direction relative to the handle or wire passageway of an associated welding gun. In contrast to conventional welding guns, an operator does not have to constantly depress the trigger or use a locking mechanism. Additionally, if an apparatus according to the present invention is accidentally dropped, the trigger or active touch switch is not accidentally activated, unlike typical mechanical switches.

Although the invention has been described by reference to a specific embodiment, it should be understood that numerous changes may be made within the spirit and scope of the inventive concepts described. Accordingly, it is intended that the invention not be limited to the described embodiment, but that it have the full scope defined by the language of the following claims.