JPS622331Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a welding stud that fastens a member to a metal support by inserting the shaft of the stud into a hole in the member. A radially projecting coiled ridge surrounds the shank of the stud and has a tip defined by flanks on either side of the ridge, which prevents the member from being withdrawn from the shank. It is something that we have learned to resist.

West German utility model No. 735052 is known as this type of welding stud. The ridges of this welding stud are designed to have an equilateral triangular cross-section, with one side of the triangle extending generally radially to the shaft. In the case of welding studs of this type, it is necessary that the tips of the ridges be as sharp as possible, since this creates a particularly high resistance to the component being pulled out of the shank. The tip is formed during the rolling process, during which appropriate pressure is applied to the shank by a rolling tool. The rolling tool has a corresponding groove at its tip, into which groove the material of the shank flows. However, conventional ridge shapes make it difficult to flow material into the grooves of the rolling tool. In order to properly force the shank material to the bottom of the rolling tool groove and form a sharp tip, it is necessary to apply pressure to the shank over a relatively large area and to flow a significant amount of material. This is because there is.

The object of this invention is to create a ridge of a shape that allows a particularly sharp tip to be formed when the ridge is rolled. The purpose of this is to form the ridge in accordance with this invention with a groove with a cylindrical root, and to form the ridge on one side of the ridge remote from the welding tip to be welded to the metal support, i.e. near the root. This is achieved by making the slope steeper than the related flank, that is, the side surface near the tip, so that the one side surface gently connects to the related flank.

To form a groove with a cylindrical root, it is necessary to equip the rolling tool with a corresponding protrusion that cuts radially into the shank material and thus forces the intervening material radially outwards. However, this shape allows for better material flow, allowing the material to move easily into the groove of the rolling tool.
A sharp tip can be formed there. In this case, the flank forming the tip is relatively flat and need only be designed relatively short, which is very effective in forming a sharp tip.
Conversely, the longer flanks can be designed approximately radially. These flanks can be easily rolled by the protrusions of a rolling tool.

As mentioned above, at least one side of the ridge is steeper than the associated flank. That is, it extends approximately in the radial direction. The other side of the ridge can be designed in such a way as to form the other associated flank. Of course, this other side also extends in the radial direction. However, this other side surface can be provided with a particularly steep slope, such that this flank extends approximately radially perpendicularly. In this case, the relevant flanks of the ridges will be slightly less steep than said flanks. Therefore,
This side of the ridge continues, forming a steep slope, into a generally radially extending flank. In the latter case, this results in a unique sharp tip, ie a unique acute angle at the tip of the ridge.

Embodiments of the invention shown in the accompanying drawings will be described below.

The welding stud 1 shown in FIG. 1 has a welding tip 2, a flange 3, and a shank 4, on which a ridge 5 is rolled following the helical winding of a screw. . The opposite end of the welding tip 2 has a conical shape so that it can be easily inserted into a hole in the structural material or component.

FIG. 2 shows the exact cross-sectional shape of the ridge 5. The figure shows a cross section in which a portion of the shaft 4 is provided with a ridge 5. The ridges 5 are separated from each other by grooves 7, which grooves 7 have clear troughs 8, which in the figure are cylindrical. One side of the groove 7 forms a flank 9, and the other side 10 of the groove 7 is connected to another flank 11, with a correspondingly gentle slope. Flank 9 and flank 11 intersect at tip 12.

As can be seen in the figure, the groove 7 is rolled by means of a protrusion of the rolling tool which extends mostly in the radial direction, with the result that a distinctive flattening is produced in a relatively narrow area, namely in the area of the flank 11. It's only good. Since the flank 9 extends almost radially toward the flank 11, a sharp tip can be easily formed at the point where they intersect.

The cross-sectional view of the ridge shown in FIG. 3 has a different shape compared to the embodiment of FIG. Instead of the flank 9 being on the relevant side of the groove 7 in the embodiment of FIG. 2, in the embodiment of FIG.
3 are generally radially shaped, creating a unique acute angle at the tip. Frank 13
is derived from the associated flank of groove 7, which here has a somewhat gentle slope, so that flank 14 forms a correspondingly steeper slope while flank 13
The shape is similar to that of the continuous example.

[Brief explanation of the drawing]

1 is a side view of the welding stud, FIG. 2 is a sectional view of the ridge of the welding stud, and FIG. 3 is a sectional view of the ridge of the welding stud of another embodiment. In the figure,
Reference numbers of main parts are as follows. 1...Welding stud, 2...Welding tip, 3...
...flange, 4...shaft, 5...ridge, 6...
Conical part, 7...groove, 8...bottom, 9...flank, 10...other side of groove 7, 11...other flank, 12...peak, 13...flank,
14... Side of the groove.

Claims (1)

[Claims for Utility Model Registration] (1) A welding stud for fastening a member to a metal support, the shaft of the welding stud being inserted into a hole in the member, the shaft having: A radially projecting coiled ridge is formed surrounding the shank, the ridge having a distal end formed by flanks on both sides, whereby the shank In a welding stud adapted to resist withdrawal of the member from the welding stud, the trough of the shank has a cylindrical trough between the ridges, the side of the ridge remote from the welding tip The member fastener is comprised of a flank surface near the tip having a relatively gentle slope, and a flank surface near the bottom of the valley that is continuous with the flank surface and has a steeper slope. Welding studs for use. (2) The welding stud according to item 1, wherein the side of the ridge near the welding tip forms a uniformly sloped flank. (3) The welding stud according to item 1, wherein the side of the ridge near the welding tip has a steeper slope near the top than the flank near the bottom of the valley.