DK142165B - PROCEDURE FOR COLD PRESSURE WELDING - Google Patents

Description

(φ) \ Ra / (11) PRESENT ELSCRIPT 1 ^ 2165 DENMARK <«> Int-CI. 'B 23« 20/02' (21) Application No. 4198 / 7½ (22) Filed dsn 7 Aug. 197½ (24) Race stage 7 · & Ug. 197½ (44) The application presented and - p. IQOn the disclosure document published on the 3 * F * DIRECTORATE OF, PATENT AND TRADEMARKETS (30) Priority requested from the

Sep 5 1975 # 2544658, DE

Sep 5, 1975 # 2544705 # $ £> (71) METALL-WERK MERKUR GMBH., Bestwig, Kap ellene tr as se, DE.

(72) Inventor: Heinz F.W. Suppus, Meschede, Heidering I9a # (74) Plenipotentiary;

The engineering firm Lehmann & Ree._.

(64) Cold pressure welding method.

BACKGROUND OF THE INVENTION 1. Field of the Invention The invention relates to a method of cold pressure welding in which two articles are moved in the direction of the welding surface relative to one another, and the welding surface of one of the articles has parallel spaced apart ribs which, when pressed, are cold welded to at least one wall in a recess in the other. blank, and which recess is made with sub-dimensions relative to the thickness of the first blank and, furthermore, in cross-section, narrows down to its bottom and has an opening slightly narrower than the ribbed blank.

From the specification to German publication specification No. 2,132,139 2 142165 it is known to use a cold pressure welding method of the kind mentioned, in which the ribs extend parallel to the direction of compression of the workpieces. The use of this cold pressure welding method in the manner described in connection with workpieces having ribs has been found to be particularly suitable for aluminum workpieces, which are particularly concerned with the present method. However, the manufacture of the workpiece carrying the ribs is particularly complicated in the case of fabrication by extruding and, in particular, in the case of articles which are to be longitudinally connected to each other in length, due to the tolerances which must be adhered to.

The object of the invention is to further develop and improve the described cold pressure welding method so that this cold pressure welding method, without having to produce the items by a complicated manufacturing technique, can be used economically for molded, board or planked articles, i.e. that, in part, advantages must be obtained with respect to the manufacture of the aluminum profile parts, which are preferably to be manufactured by string pressing, and at the same time welding of the two parts must be possible by hand-operated spindle presses or otherwise operated simple presses, whereby the parts themselves can be thin-walled profiles.

In order to solve this task, the invention proposes that the prior art cold pressure welding method described above be used in such a way that the ribs extend perpendicular to the direction of insertion and have trapezoidal cross sections.

The ribs according to the invention may preferably have a width of 0.15-0.3 mm at their outward-facing outer edges and at this edge have angles of up to 40 ° with respect to the perpendicular to the insertion direction, whereby the recess of the second workpiece is narrowed by 0. 1-0.3 mm towards the bottom and the insertion distance of the ribbed workpiece into the recess of the other workpiece is 3 ”7 mm.

The manufacture of extruded profiles with longitudinal ribs extending in one of the workpieces is considerably simpler than the preparation of the articles used in the known methods of cold pressure welding, where preferably ribbed intermediate elements are to be used. In such cases where molded articles need to be connected to each other at their longitudinal edges, one item can be easily connected to the other by a hand operated spindle press or an otherwise operated simple press whose opening corresponds only to the compression section plus the thickness of the article instead. for its width.

The cross-sectional flanges at their outer edges guarantee a uniform rib height in the manufacture of the ribbed workpiece, so that a uniform or approximately uniform welding effect is obtained both over the height and the length of the ribbed part.

In order to obtain an advantageous flow of the material at the recess walls, without subjecting the walls to deformation or damage such as notches or the like, and to obtain a large weld surface for each rib, the ribs must, of course, be at least at their outer surface. slenderness degree. The depth of the recess is also of great importance for the method of cold pressure welding according to the invention. If the insertion distance of 3 mm is less than 3 mm, no effective welding is achieved. However, if the maximum value of 7 mm is exceeded, already welded sections will again be torn apart, which adversely affects the strength of the connection. According to the invention, the cross-section of the recess and its wall dimensions affecting the welding and pressing force must be selected such that the specific load of the ribs is plastically deformed at their outer edges, while the specific load of the recess wall to eliminate deformation of the recess wall is not allowed. exceeded.

German publication specification No. 2,060,728 discloses a printing path view method and an apparatus for producing by means of diffusion a fixed connection between blanks, especially pipe blanks, of materials of different melting point. Here, one of the workpieces is provided with teeth or ribs extending perpendicular to the direction of movement of the workpieces. In preparing the compound, the blanks are heated under vacuum and pressed under high pressure against each other so that the liquid of one blend material flows in the spaces between the teeth or ribs of the other blanks whose material has a higher melting point. A welding and deformation of the rib ridges with a counter surface by means of the relative movement between the two blanks is not effected here.

In German usage pattern No. 6,751,361, it is known without welding or screws to connect two drawn or extruded parts with the other, the ends with which the parts are to be connected to each other, each having a longitudinal rib, on which may be affixed to a cross section U-shaped profile list provided with longitudinally extending teeth at the inside of its lateral flanges, and the distance between the teeth at the same height of the teeth of the two molding flanges in the initial state is less than the width of the ribs. two parts are joined together, the teeth in the tooth of the U-shaped profile molding slide first along the outside of the rib of the other workpiece until the rib has completely or approximately reached the bottom of the U-shaped profile part. The two 4 142165 parts are held together by the bar-like teeth of the U-shaped profile as these teeth engage the material of the ribs. A welding does not take place here, however.

As described in English Patent No. 983,144, it is known by cold pressure welding to weld a first cross-section L-shaped workpiece in a recess narrowed against its bottom in a second workpiece. Below this, the end of the branch of the L-shaped workpiece to be recessed in the recess extends slightly above the side edge limiting the recess. During the depression of the branch in the recess narrowed to the bottom by means of a tool, the recess wall is pressed against the first blank by means of another tool so that the outer edge of the branch and the recess wall are both deformed. This gives flat weld sections. Thus, in this known method, two cross-sectioned and precisely spaced tools are required to be operated simultaneously.

According to a further embodiment of the method according to the invention, the rib flanges extend into surfaces which are curved in cross-section. This peculiarity offers the possibility of a simplified manufacture by string pressing the ribbed workpiece. In addition, the one item provided with the ribs at the foot of these may have a smaller thickness than the width of the groove bottom.

In the following, the method according to the invention will be explained in more detail with reference to an exemplary embodiment illustrated in the drawing. In the drawing: FIG. 1-3 use possibilities of the cold-piece welding method for forming a workpiece in the form of a single or double-wall molded or board-shaped element; 4 and 5 are the two enlarged items and the parts in the embodiment of FIG. 6 shows rectangle A, and fig. 6 is a workpiece with stepped, ribbed surfaces, the other workpiece having a corresponding recess with stepped inner walls.

The molded or plate-shaped blanks 1, 2 according to FIG. 1 and 2 are to be connected to each other by means of the method of cold pressure welding according to the invention. For this purpose, the branch 3 of the workpiece 1 carries a recessive workpiece part 4 and the section 5, as the second workpiece 2 * s 5 1A2165 workpiece part carries a recess 6. Conversely, the workpiece of the workpiece 1 carries a recess 8 with which the workpiece workpiece workpiece part 9 of the workpiece engages. A similar design has the blanks 1 and 2 of FIG. 3 · There are the molded blank portions 4.9 located immediately on the planar wall portion 1a 2a and adjacent to the recesses 6, 8 are perpendicular kehler 6a 8a in which the longitudinal edge of the planar wall portion 1a, 2a is accommodated in such a way that the surfaces of the the wall portions 1a, 2b and 2a, 1b are at the same height when these two workpieces and the workpieces according to fig. 1, as described below, is pressed against each other in the arrow directions drawn.

The two workpieces 4, 9 have, as is clearly seen in FIG. 4 and 5, in the longitudinal direction of the sheet, board or plate-shaped members 1 and 2 on both sides of the median plane M, several in cross-section, essentially trapezoidal ribs 10 with concave vaults 11.

The recesses 6, 8 in the blanks 1, 2 have a trapezoidal cross-section, the cross-section narrowing down to the bottom 12 of the recess.

The measure of the narrowing of the recesses 6, 8 is 0.1-0.3 mm, i.e. that while the opening 14 of the recess 6, 8 has the target x, the width of the bottom of the recess is x - 0.1 to x - 0.3 mm.

The depth of the recesses 6, 8 and the length of the workpieces 4, 9, respectively, is 3 to 7 mm such that the insertion stretch of the parts 4, 9 into the recesses 6, 8 is also 3 to 7 mm.

The distance between the outward outer edges 13 of the same height ribs on both walls of the parts 4, 9 as well as between the ribs 10a and 10b in FIG. 5 is slightly larger than the width x of the opening 14 of the recess 6,8.

The width Y of each of the outward outer edges 13 is most convenient if it is between 0.15 and 0.3 mm, while the flank angle α at or near the outward edge 13 between the rib flange 15 and its extension 15a, respectively, and the projection or pressing direction (arrow 17) normal 16 maximum is 40 °. This gives a relatively slender rib, the ideal shape of which is illustrated by the flanks 18. Since the manufacture of such a rib is difficult in manufacturing, the outer wall of the workpieces 4, 9 is given an arcuate passage between the ribs 10, whereby vaults 11 are formed. of the workpiece 4.9 at the location of two vaults 11 located 11 at the same height on the walls of the parts 4, 9 is less than the width of the bottom 12 of the recess 6,8, i.e.

The thickness a of the workpiece parts 4, 9 at the height of two opposite rib feet (vaults 11) is less than the width of the recess 6, 8.

As the outer rib cam 19 (Fig. 4) projects beyond the edges 20 of the recess, this section is teared up against the edges 20 as the workpiece portions 4, 9 are pressed into the recess 6, 8, thereby removing the oxide layer on the outer edges of the ribs. During penetration of the workpiece portions 4, 9 into the recesses 6, 8, larger portions of the ribs 10 are welded to seam and pressed into the portions 21 between the ribs 10. Such portions are shown in FIG. 4 denoted by 22, 22r 22, r.

At larger width rib ridges higher compression pressures would be required which in turn would cause displacement and deformation of the recess walls 23, as is the case in the method known from the specification of the aforementioned British Patent No. 983-144. An angled outer edge of the ribs, on the other hand, would provide a weld joint with less strength.

In the embodiment shown in FIG. 6, it is taken into account that the penetration depth of the workpiece in the recess in the second workpiece must not exceed 3 to 7 mm, although the surfaces welded together are increased. For this purpose, the blank 25, as a first blank part, has a recess 24 with stepped inner walls 26, 27, 28, wherein the recess sections are designed according to the requirements described above with respect to the width w and z of the opening of the recess, the width u and v of its bottom. as well as the slope. The length of the sections in question with the walls 26, 27 and 28 is between 3 and 7 mm.

The workpiece 29 carries, as a second workpiece, a molding 30, the outer walls of which are provided with ribs 31 which correspond to the conditions described above for the design of the ribs 10. A narrower molding 33 is provided with the ribs 32. The moldings 30 , 33 are designed in such a way that they each fulfill the function of the workpiece parts 4, 9 in the embodiment according to FIG. 1 to 5. Despite the similar insertion distances of 3 to 7 mm for the workpiece 29 and the workpiece part 25, a doubling of the welding surface is achieved in relation to that of FIG. 1 to 5.