MXPA99002372A - Taper lock contact tip and head assembly for welding device - Google Patents

Abstract

A contact tip for use with a welding gun includes a tapered portion, a threaded portion, an extension portion and a gripping feature. The tip is elongated and has a first end and a second end. The tip also has a wire feed axis extending therethrough and an axial wire feed aperture extending therethrough. The tapered portion of the tip is at second end of the tip and has a frustoconical shape. The threaded portion of the tip is adjacent the tapered portion. The extension portion of the tip is adjacent the threaded portion and extends to the first end of the tip. The gripping feature is disposed on the extension portion. The tapered portion serves as a retaining feature.

Description

ASSEMBLY OF FASTENING POINT OF CONTACT AND HEAD FOR WELDING DEVICE Field of the Invention This invention is generally concerned with guns for spot welding and more in particular with a connection between a gun tip for welding and a retaining element.

BACKGROUND OF THE INVENTION The metal inert gas (MIG) welding equipment for welding a metal workpiece to another metal workpiece is well known in the welding art. A welding gun is designed to allow a user or robot to direct a metal welding wire to a specific location on a target metal workpiece. The welding wire is fed through the welding gun, and finally through a hole in the tip to be welded at the end of a gun for spot welding. The welding wire, when energized for welding, carries a high electrical potential. When the welding wire makes contact with the target metal workpiece, an electrical circuit is completed and the current flows through the wire.

REF. 29587 welding, through the metal work piece and grounded. The current causes the welding wire and the original metal of the work pieces in contact with the welding wire to melt, thereby joining the work pieces. The extreme heat causes the welding tips, usually a copper alloy, to wear out relatively quickly. Welding tips are commonly cylindrical in shape from the front of the tip to the back of the tip. The welding tips usually have screw threads for joining to the welding gun. The known soldering tips generally have a relatively short service life due to the deterioration of the material caused by the extreme heat of the welding process. In addition, many known soldering tips tend to loosen from their attachment to the welding gun when in use, to force users to stop welding in order to replace or tighten the soldering tip. It would thus be desirable to have a soldering tip which demonstrates an improved and prolonged useful life and which demonstrates a more secure joining method to the welding gun. The present invention is directed to the attention of these objectives.

BRIEF DESCRIPTION OF THE INVENTION A contact tip for use with a welding gun includes a tapered portion, a threaded portion, an extension portion and an attachment or attachment. The tip is elongated and has a first and second end. The tip also has a wire feed shaft extending therethrough and a feed orifice of the axial wire extending therethrough. The tapered portion of the tip is at a second end of the tip and has a frusto-conical shape. The threaded portion of the tip is adjacent to the tapered portion. The extension portion of the tip is adjacent to the threaded portion and extends to the first end of the tip. The attachment or attachment is arranged on the extension portion. The tapered portion serves as an attachment or retention attachment. A combination of a contact tip and a welding gun includes the tip and the retention element of the tip. The tip has a tapered portion, a threaded portion, an extension portion and an attachment or attachment. The tip retention element has a wire feeding opening or hole extending therethrough and engaged by the tip. The tip has a first end and second end, and a wire feed shaft extending therethrough. The tip also has a wire feeding opening that passes axially therethrough. A tapered portion of the tip is disposed at the second end and has a frusto-conical shape. A threaded portion of the tip is adjacent to the tapered portion. An extension portion is disposed at the first end. An attachment or attachment is disposed on the extension portion. The retention element of the tip has an end and opening or feed hole of the wire aligned with the feed opening of the tip wire. The opening at the end of the retention element of the tip receives the second end of the tip. The tip retainer has internal threads engaged by the threads of the tip and has a tapered seat complementary in shape with the tapered portion that is engaged by the tapered portion of the tip. When the tip is subjected to a rotational tension moment in a tightening direction, the tip will resist the removal of the tip retainer due to the locking engagement between the tapered portion and the seat.

The described solder tip, in combination with a tip retainer, provides a soldering tip that has an improved and prolonged service life and also provides a more secure method of retention of the tip in the tip retainer .

DESCRIPTION OF THE DRAWINGS Figure 1 is a perspective view of a portable welding gun showing the tip of the invention and a nozzle. Figure 2 is a cross-sectional side view of a first embodiment of the tip of the invention and nozzle. Figure 3 is an end view of the tip and nozzle of Figure 2 in the direction of arrow three of Figure 2. Figure 4 is a sectional side view of a second embodiment of the nozzle and tip. Figure 5 is a view of the end of the nozzle and the tip of Figure 4 in the direction of arrow 5 of the figure. Figure 6 is a side view of a robotic gun assembly.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A portable welding gun 10 shown in FIG. 1 includes a handle 12, a goose neck 14, a retaining head nozzle or a tip retainer 16, and a tip 18 of Contact. An interface between the contact tip 18 and the nozzle 16 of the retaining head have been configured to improve the retention of the tip 18 by the nozzle 16 and to facilitate rapid separation of the tip 18 from the nozzle 16. The tip 18 as shown in figure 2 it is elongated in shape and has a first end 22 and a second end 24 arranged opposite. A shaft 26 of the tip passes through the first end 22 and the second end 24 in the center of a feed opening 28 of the wire passing through the tip 18. The opening 28 has a tapered receiving end 30 in the second. end 24 of the tip 18 to facilitate reception of the wire passing through the tip 18. A tapered portion 32 of the tip 18 is disposed at the second end 24. An included angle A of the tapered portion 32 is approximately 20 °. A threaded portion 34 is disposed on the tip 18 adjacent the threaded portion 32. The threaded portion 34 has approximately 2% threads. The relatively short thread length facilitates rapid separation of the tip 18 from the nozzle 16. The total length of the threaded portion would be about 3% times the thread width. A portion 36 of the separation diameter is provided on both sides of the threaded portion 34. A portion 38 of extension slightly larger in diameter than the separation portion 36 extends from the first end 22 to the closest separation portion 36. The extension portion 38 may assume any of several embodiments, in which they include a cylindrical shape and a cross-sectional shape of hexagonal shape. The extension portion includes an attachment or attachment 40, an attachment or attachment 40 as shown in Figures 1-3 comprises a pair of parallel planes at the first end of the tip 18. Alternatively, the accessory or attachment Fixation could be provided by using an extension portion formed hexagonally with three pairs of opposing planes. The planes 40 are only accessories or exemplary fastening devices. Other forms that require tools instead of an open end wrench can be used as an attachment or attachment. Additionally, the tip 18 has a bevel 42 at the first end 22. The nozzle 16 of the retaining head has a first end 46 and a second end 48 with a longitudinal axis 50 passing therethrough. The longitudinal axis 50 is coincident with the axis 26 of the aim. An axial opening or hole 52 extends along the axis 15 in alignment with the wire feed opening 28. A portion 54 of a first axial opening diameter 52 it is disposed at the first end 46 and has internal threads 56 disposed therein. A portion 58 of a second diameter of the opening 52 is disposed at the second end 48 and is smaller in diameter than the portion 54 of the first diameter. The portion 58 of the second diameter has internal threads 60 disposed therein. A tapered seat 62 in the portion 58 of the second diameter is complementary in shape with the tapered portion 32. The included angle A is selected to provide a locking or locking effect when the tip 18 is subjected to a torque in a direction of tighten in the nozzle 16 of the retaining head. The nozzle 16 includes a transition region 64 in the axial opening 52 between the portion 54 of the first diameter and the portion 58 of the second diameter. Gas orifices 66 pass from the transition region 64 to the exterior of the nozzle 16 and are oriented in such a manner that the inert gas passing from the interior of the nozzle through the orifices 66 displaces the air around the first end 22 of the nozzle. the contact point 18. Figures 4 and 5 show an alternative embodiment of the invention in which the included angle A is appreciably smaller than that of the first embodiment, to result in a much greater resistance to unintentional loosening of the tip, to thereby make the separation of the tip 18 much more difficult. Figure 6 shows a gun 70 for robotic welding with a welding wire 71 connecting it to the connector 72. The connector 72 is received by the arm 74 in a predetermined rotary position. The arm 74 is in turn attached to a safety assembly or clutch 76 fixed rigidly to a robot arm (not shown). The tip 18 and the nozzle 16 are used in the following manner. The internal threads 56 in the portion 54 of the first diameter of the nozzle 16 are screwed onto a sleeve mounted at one end of the goose neck 14 or 78. The tip 18 has a threaded portion 34 threaded into the internal threads 60 of the nozzle 16 until the tapered portion 32 engages the seat 62. Having the separation portion 36 between the threaded portion 34 and the extension portion 38 is it facilitates obtaining a clamping coupling between the tapered portion 32 and the nozzle 16 by preventing engagement of the extension portion 38 against the nozzle 16. The axial force induced by the threads in response to a torque applied between the tip 18 and the nozzle 16 wedges the tapered portion 32 to the seat 62, to develop a frictional load between the tip 18 and the nozzle 16 that resists relative movement between the two parts. Since tip 18 has only 2 threads, separation and replacement can be done quickly. The more conventional tips that aipleai a large number of threads to obtain the desired clamping load necessary to retain the tip, take a long time to separate and install in comparison. The use of the tapered coupling between the tip 18 and nozzle 16 allows the use of fewer engaging threads on the tip 18 as long as a sufficient amount of retaining force develops between the parts to keep them engaged. The tapered coupling also provides a large contact area between the tip 18 and the nozzle 16 to facilitate rapid heat conduction of the tip 18. The weld wire of the gooseneck 14 or 78 passes through the holes 52 and 28 The entrance of the welding wire to the opening or hole 28 is aided by the transition region 64 and the tapered receiving end 30. The embodiment of Figures 4 and 5 are essentially the same as those of Figures 2 and 3, except that the angle A of Figures 4 and 5 is much smaller resulting in a higher level of clamping load between the two parts. what is generated The foregoing description is exemplary rather than limiting in nature. A preferred embodiment of this invention has been described to enable one skilled in the art to practice this invention. Variations and modifications are possible without deviating from the spirit and scope of the invention, the scope of which is limited only by the appended claims.

It is noted that in relation to this date, the best method known to the applicant to carry out the aforementioned invention, is the conventional one for the manufacture of the objects or products to which it refers.

Claims (1)

CLAIMS Having described the invention as above, property is claimed as contained in the following:

1- A contact tip for use with a welding gun, the tip is formed into a tip that includes a first end and a second end and has a wire feed shaft that extends through it, and includes a opening or feed hole of the wire that passes axially therethrough, characterized in that: it includes a fastening fitting disposed on an extension portion at the first end and a tapered portion at the second end of the tip having a frusto-conical shape , the tip also includes a threaded portion adjacent to the tapered portion; the tapered portion is designed to mate with the tapered seat in a welding gun nozzle which is complementary in shape to the tapered portion of the tip, and which consequently serves as an attachment or retention fitting; and the threaded portion has a short axial length that allows the tip to be quickly unscrewed. 2. The soldering gun contact tip according to claim 1, characterized in that the included angle of the tapered portion is not greater than about 20 °. 3. The soldering gun contact tip according to claim 1, characterized in that the attachment or attachment includes at least one flat surface. 4. The contact tip according to any of claims 1 to 3 in combination with a retaining head nozzle and a welding gun, characterized in that the combination includes: a retention element of the tip that has one end and having a wire feed opening or hole aligned with the feed opening or hole of the tip wire, the wire feed opening at the end of the tip retaining element receives the second end of the tip and has threads internal ones coupled by the threaded portion of the tip and a tapered seat coupled by and complementary in shape to the tapered portion of the tip; wherein, when the tip is subjected to a torque or torque in an adjustment direction, the tip will resist being withdrawn from the tip retainer due to the locking engagement between the tapered portion and the seat.