EP0879657A2 - Method and apparatus for producing a hollow body - Google Patents

Abstract

Automobile hoods and doors etc., in the form of hollow bodies, are manufactured by a method in which at least two panels, preferably of sheet steel, are held tightly together along an at least almost closed line and are formed into the hollow body with the aid of an internal high-pressure forming process. The panels are forcibly joined together. The joining process may be carried out before, during and/or after forming. Also claimed is equipment for carrying out the process comprising an upper tool (4) attached to a ram (2) which can move up and down and a lower tool (5), fastened to a press table (3), in which a supplementary tool is integrated. A lance (7) supplies pressure medium into the a between the sheets (12, 13).

Description

The invention relates to a method and a device for producing a hollow body, preferably from Sheet metal, such as an automobile hood, door or Like., in which the so-called hydroforming (IHU) process is used.

The German patent application 42 32 161 describes a process for producing a hollow body under Use of a basic body made of circuit boards, in which the hollow body by a combined application of the IHU and deep drawing processes becomes. This proposal is characterized in that first the base body from two identical edge dimensions having printed circuit boards is produced, the one another placed and welded together at the edge will. After inserting the base body into a mold and the closing of the base body takes place by means of the above-mentioned process to a hollow body. After the forming process is finished, more will follow Processing steps.

Apart from that, separately in this proposal a basic body must be produced, which is then in the tool shape is inserted - which is at least two requires additional work steps - this is liable Processes the disadvantage that only due to weld seams symmetrical with regard to their upper and lower parts Workpieces can be manufactured. In addition, must the hollow body after forming due to surface damage by deep drawing in the edge area of the component be treated; others close necessary processing steps, such as Cutting the width due to the type of forming Flange and / or post connection of the boards, what to happen in further separate stations Has. The process is characterized by a large number of processing steps to be carried out one after the other and is regarding the product range extremely limited.

Against this background, the object of the invention based on a method for producing a hollow body in view of the constantly increasing time and cost pressure, especially in the automotive industry, more efficiently and thus more cost-effective and more flexible.

The method according to the invention solves this problem the features of the main claim. The procedure is suitable especially for the production of multi-walled components, which are particularly suitable for body construction, such as automobile hoods and doors, tailgates and roofs, and can advantageously be in just one Tool.

After cutting the original boards, they become into a design to be described according to the invention special hydroforming (IHU) tool inserted, held close together in their edge areas and then using the hydroforming process (IHU) formed into a hollow body. For Stabilization and final connection of the boards they are enforced at appropriate points. These manufacturing steps - sealing, forming, clinching - Can be according to the invention with considerable Advantage in only one tool and in almost any Carry out sequence as well as overlapping.

If here from "kept close together" or "Keeping tight" is thus sealing of the two boards against each other that meant the application enables the IHU procedure without at least noteworthy pressure medium in the deformation of the boards during the formation of the cavity or the Cavities between them can escape to the outside. The can, for example, by applying adhesive strips between the boards, by flanging the Flange areas of the boards as well as a combination of both can be achieved, the flange areas or the sealing line (s) during forming by appropriate Devices additionally with one for sealing sufficient pressure can be applied, using the appropriately trained tool. The tightness is created by positive locking. With appropriate Sealing pressure (contact pressure along the sealing line) the boards are also at least in places cold welded, what for the inventive method is not mandatory but is advantageous.

In one embodiment of the invention, the boards in Connection area, preferably in the folded corner area plastically pressed, resulting in a more reliable seal leads. To do this, use the tool - as detailed below executed - modified, namely by an additional provided drawing ring as part of the lower drawing punch.

In a further embodiment of the invention, the special IHU tool at least one further processing step during, overlapping and / or after the IHU process carried out. About these processing steps include punching, punching, sealing including the at least prepared attachment of Fasteners and the like.

For the sake of completeness it should be mentioned here that too Components from other industries, such as Panel radiators or similar components with the invention Processes can be made.

Fig. 1

einen Querschnitt durch ein bevorzugtes Ausführungsbeispiel eines IHU-Werkzeuges;

Fig. 2

eine Draufsicht auf das Unterteil des in Fig. 1 dargestellten IHU-Werkzeuges mit erfindungsgemäß eingebauten Hilfswerkzeugen;

Fig. 3

einen Querschnitt durch ein besonders bevorzugtes Ausführungsbeispiel, entlang der Linie III-III in Fig. 4 geschnitten;

Fig. 4

einen hälftigen Querschnitt des in Fig. 3 dargestellten Ausführungsbeispiels, entlang der Linie IV-IV in Fig. 3 geschnitten;

Fig. 5

eine hälftige Draufsicht auf das in Fig. 3 dargestellte Ausführungsbeispiel zur Verdeutlichung der Lage der Andockstellen;

Fig. 6

den Ausschnitt X aus Fig. 3 vergrößert zur Verdeutlichung des Bereichs der Platinen-Kaltverschweißung; und

Fig. 7

eine Andockstelle des für die Variante gemäß Fig. 3 vorgesehenen stationären Andocksystems.

Preferred variants of the method according to the invention are explained in more detail below on the basis of the exemplary embodiments illustrated in the drawing. The drawing shows:

Fig. 1

a cross section through a preferred embodiment of an IHU tool;

Fig. 2

a plan view of the lower part of the IHU tool shown in Figure 1 with auxiliary tools installed according to the invention;

Fig. 3

a cross section through a particularly preferred embodiment, cut along the line III-III in Fig. 4;

Fig. 4

a half cross section of the embodiment shown in Figure 3, taken along the line IV-IV in Fig. 3.

Fig. 5

a half plan view of the embodiment shown in Figure 3 to illustrate the location of the docking points.

Fig. 6

the section X from FIG. 3 enlarged to clarify the area of the cold plate welding; and

Fig. 7

a docking point of the stationary docking system provided for the variant according to FIG. 3.

The method according to the invention is illustrated by way of example described the manufacture of an automobile hood. In figure 1 is a special hydroforming tool 1, namely an hydroforming (IHB) tool shown with a plunger 2 and a press table 3. The plunger 2 is up and down according to arrow A. removable. The plunger 2 enters at the bottom Tool upper part 4. Correspondingly is on the press table 3 attached the associated lower tool part 5. Tool upper 4 and lower tool part 5 form when closed IHB tool 1 the hollow body negative mold, i.e. the boundary surface against which the one to be manufactured Hollow body is pressed through the IHU process, and what it gets its final, repeatable shape. It is conceivable to use this negative form with movable counter pressure parts for variable shaping of the ones to be manufactured To design hollow bodies.

A pressure medium supply is furthermore in the IHB tool 1 6 integrated in the manner of a docking system, too a lance 7 and a connection 8 with one not shown media storage belongs. The docking system 6 is in this embodiment in the lower tool part 5 installed that his lance 7 towards of the hollow body 9 to be produced is movable and a constant supply of pressure medium through the connection 8 is guaranteed. The docking system 6 could also between Tool upper part 4 and lower part 5 arranged the medium feed from the side in the hollow body 9 would take place.

To carry out further processing steps in the same IHB tool 1 makes it possible to add this timed and spatially corresponding to each other integrate associated tools, such as Punching tools 11 for making perforations and / or large openings in the hollow body. These recesses can be used, for example, for attachment of lanyards, the laying of lines and in the case of fluid receiving components for the supply or Outflow of the fluids can be used. Big breakthroughs are suitable for improving the vibration properties.

The method according to the invention for producing hollow bodies An advantageous embodiment is made of circuit boards according to the following steps:

First, the starting sheet metal boards - at one Automotive hood can be the outer skin board 12 and one Inner frame board 13 - on a coil system cut and if possible the front sides - Based on the hood to be manufactured - The outer skin boards 12 at an angle greater than 90 ° angled. The reason for bending at an angle greater than 90 ° is explained below. Should this Bending process cannot be integrated into the coil tool be a fold after cutting in one Preforming tool possible. The ones to be connected Boards 12, 13 can be inserted into the IHB tool 1 with adhesive strips on the inside of the outer skin board 12 pre-fixed on the bevelled end faces will. These adhesive strips have in addition to the pre-fixing Effect the task of sealing the boards against each other as well as absorb vibrations and corrosion to avoid between the boards.

Once the inner skeleton board 13 into the outer skin board 12 placed and both placed in the IHB tool 1 are closed by lowering the plunger 2. The angled faces of the outer skin board 12 automatically crimped as it already have been angled by more than 90 ° so that these the flanks of the end faces of the board of the inner frame 13 after you close the tool. At the same time, the side edges 14 of both boards 12, 13 with also movable up and down, a certain Applying feed force, built into the upper part 3 of the tool Stamp 15 angled - preferably around 90 ° - and then through horizontally movable, over the Entire edge length extending in the lower part of the tool 5 integrated, strip-shaped stamps 16 as strong pressed together that the boards 12,13 along their entire length are held so close together that no forming medium can escape. It can even partially or completely cold welding takes place. On the end faces of the hollow body 9, which during or flanged by moving the plunger 2 down the flanging ensures the necessary Tightness. At this point it should be mentioned that Bending in the IHB tool 1 also along an in closed line - i.e. along all outer flanks - can be done; it is also conceivable that all edges before inserting them into the IHB tool 1 unwound and flanged by lowering the plunger 2 will.

In this way, the boards 12, 13 along their Edge areas held tightly against each other, so that during the subsequent hydroforming no pressure medium from the cavity 17 between the boards 12, 13 can escape and so the necessary for molding High pressure can build up in the hollow body. On the side angled flanks 14 can after the manufacturing process Edge rubbers to protect the water channel in the Front area of the car be plugged on.

Furthermore, while the IHB tool is closing 1 the lance 7 of the docking system 6 in the direction of the circuit board of the inner frame 13 moves. With the help of lance 7 becomes the pressure medium during hydroforming conveyed into the cavity 17 between the boards 12, 13 and built up a hypertension. To do this, it is necessary one of the two kept close to each other To pierce boards 12, 13 with lance 7 if not a pressure medium inlet opening from the outset in one of the boards 12, 13 or in the edge area between this is provided. However, it must be avoided to pierce both boards 12,13, otherwise the for the build-up of an internal high pressure required tightness is not given.

There are for piercing one of the boards 12, 13 various possibilities; here is an example Suck the board through which the lance 7 of the docking system 6 should be mentioned, by means of a "feeder", whereby the superimposed boards 12, 13 be pulled apart and a puncture of both Boards 12,13 is avoided.

Should the introduction of this passage point be due the geometry of the component to be manufactured is not possible must be before connecting the boards 12, 13, for example while cutting on the coil system, a hole is made in the place of the board, where the print medium feed is located after insertion 6 is located in the IHB tool 1.

The lance 7 is designed such that during the forming no pressure medium can escape from the hollow body. This is done, for example, with a conical lance end reached.

As soon as the IHB tool 1 is closed and thus the End faces are flanged, as well as the side flanks 14 of the boards 12, 13 are pressed together and that Docking system 6 is connected to the workpiece, that is Forming medium in the interior 17 of the hollow body 9 between the boards 12,13 promoted. As a forming medium fluids as well as gases and foams are possible; the latter can be used after the forming process certain applications remain in the hollow body, because they have a positive effect on the damping or vibration properties of the entire component.

By penetrating the forming medium into the interior 17 and the build-up of the pressure takes place as well the final calibration when the maximum pressure is reached (Forming e.g. fine corner radii) of the boards 12.13 in their final form.

At this point it should be mentioned that it is for the later The quality of the component is important in the area of Joints of the boards 12, 13, here in the area their front edges and side flanks 14, during the forming process due to the maintained clamping effect no deep-drawing process when the mold is closed takes place, which is a particular advantage of the invention because there is no material flow in these areas takes place, which negatively affects the component properties, especially the surface quality would.

With the help of the method according to the invention it is in time and cost saving possible, further processing steps on the hollow body both during and also overlapping and after completion of hydroforming perform. These additional processing steps become advantageous in the IHB tool 1 performed. Removal and reinsertion in another tool is therefore not required.

These processing steps include enforcement of the flanks 14 for connecting the boards 12, 13 by means of individual stamps 18 which can be moved horizontally Ledge stamp 16 stored and relative to this are also horizontally movable, for example Hole operations in the outer skin board 12 and / or in the inner frame board 13 and the insertion larger openings in the inner frame board 13, the functions of which were explained above.

Punching can be done in different process variants be performed. For example, here are punching "inside", punching "outside" and punching "with slugs remaining on the component".

When punching "inwards", the punching or cutting tool moves with its punch end 19 during or too after hydroforming (s) into high pressure acted upon hollow body, remains during the forming there and thereby prevents the Print medium. The punched slugs then remain in the hollow body.

Punching "outwards" takes place in two steps. In The hole or cutting tool moves in a first step 19 during the IHU process against the hollow body and penetrates so far into the wall that a predetermined breaking line arises; in the second step the tool 19 at high speed with maximum internal high pressure suddenly pulled back. The breaks Board material along the predetermined breaking line and will pushed out as a slug; there is a certain Pressure medium escapes and thus a pressure drop in the hollow body, which is negligible.

When punching "with slugs remaining on the component" the hole or cutting tool in one place Stamped edge blunt so that in part of the Hole area remains a connection, whereby the punched slug is folded inwards and remains connected to the board and therefore not loose in the Hollow body remains. The punching end of the hole or The cutting tool can remain in the hollow body until the internal high pressure is reduced again. Of the in this way, remaining slugs also brings no problems with painting because in the area of the folded up piece therefore a paint application is possible because the slug does not touch the system Inner surface of the wall is folded down.

As soon as all processing steps have been completed the suction of the forming medium from the interior 17 of the component - unless in the case of use of foam as a pressure medium, this should be from the above Reasons remain in the workpiece - as well as the IHB tool 1 either through the pressure medium supply 6 or through another special, integrated, here Not shown device.

After opening the IHB tool 1 there is a complete finished component, to which only - if necessary - Brackets for the connection of fasteners, and the locking mechanism screwed, riveted or need to be dotted.

3 to 7 is a particularly preferred embodiment the invention shown in his essential structure although the previously described corresponds, but by changing some details brings special advantages, namely on the one hand an optimized seal at the connection areas of the boards and on the other hand a simplified, in contrast to the previously described embodiment stationary docking system.

The optimized sealing is in this embodiment achieved according to the invention in that a Sealing edge made in the corner of the edge (see also Fig. 6) is, namely at the transition from the so-called "Frame" (that's the angled one in the drawings sheet metal or board edge area running vertically downwards) to the actual hollow body (here bonnet). This eliminates angling or folding the boards before inserting them into the IHU tool Generate the side edges 14 - rather this area accordingly during the closing of the tool deformed - as well as the stamps 15, 16 and 18, which is a considerable Saving in construction costs means and the tool both in terms of its construction and also its additional controls essential simplified. This is achieved through a modified Design of both the lower tool part 5 and also the upper tool part 4, which, as shown in FIG. 3, laterally over the middle of the lower part of the tool is pulled down, which in turn is in a central, movable drawing punch 21 and a surrounding Drawing ring 22 is divided. Between the drawing ring 22 and the upper tool part 4 is a hold-down 23, which also projects upwards, the movable one Drawing stamp 21 also comprising collar-like Section 22a (see also Fig. 3 and 4) surrounds the outside.

6 shows in the circle drawn there the area of the cold plate welding which is brought about by the interaction of the force F _{S of} the drawing ring 22 and the die force F _M when the tool is closed. This eliminates the hydraulic pressing of the frame provided from the side via the hydraulic cylinders, as well as the angling or folding before inserting the blanks into the hydroforming tool or, alternatively, the angling in the tool via the punches 15, as provided in the exemplary embodiment described above, since this The process takes place automatically when the tool is closed after inserting the workpieces (blanks) as described above, with the result of cold welding. At the same time, this has the further advantage that no defined assignments of the sheet metal regions pre-deformed before insertion into the tool are necessary, which is a condition for reliable sealing of the sheets to one another in the embodiment described above.

This achieved in the embodiment described here Corner weld, like the one shown in Fig. 6 Force directions show from above or below and is not reached from the side, is denser and to manufacture more precisely because otherwise a relative large area to be sealed. It can also be used Adhesive strips for fixing the relative position and / or additional Seals are dispensed with.

It should also be mentioned that due to the function of the Hold-down device controlled when closing the tool Material flow in the frame area is reached of considerable importance for the reasons given below Advantage is. It should be mentioned about the manufacturing process, that the hold-down 23 in the starting position in Edge area of the inner board from below, while the die rests on the outer board 14 from above, and when closing the tool between the hold-down device 23 and the die 4, the edge regions are clamped in this way be that over the outer edge of the pull ring collar 22a in the later board connection and sealing area a downward deformation occurs so that first a Z-shaped cross section for the edge area results, namely starting from that of the upper end face of the collar 22a abutting the vertical Area between the outer surface of the collar 22a and the Inner surface of the die 4 pulled down to finally essentially horizontal again, between the die 4 and the hold-down device 23 pinched edge area.

When the die is lowered further, the between the die 4 and the hold-down clamped area 23 released according to the downward movement until it then runs completely vertically to form the frame, thus molded into the vertical frame area becomes. The extremely beneficial consequence is a wrinkle-free one Tension over the collar 22a, in particular leads to controlled on the basis of the previously described Material flow in the sealing area no folds can occur and thus the desired connection and Tightness is guaranteed.

As already mentioned, in this embodiment not a mobile, but a stationary docking system for filling and venting during the IHU process used, which in its essential embodiment in Fig. 7 and its docking points are shown in FIG. 5 result. This docking system is therefore becoming stationary called because it is provided in the stationary drawing ring 22 is in its collar 22a, that on its upper Front has a recess 24 into which it fits and resiliently supported by suitable means 25 Socket 26 is inserted, which has an internal thread and on its free, upward facing face with a conical depression 26a is provided. After inserting the board (here the inner board 13), which to the the positions assigned to the docking points with corresponding Holes are provided and at this time supported or on the edge on the collar 22a this rests with an externally threaded one Banjo bolt 27 with conically widening, the depressions 26a adapted head (27a) (see Fig. 7) in the socket 26 is screwed so that the inner board 13 in the hole area according to the representation according to Fig. 7 funnel-shaped in adaptation to the conical head 27a and the depression 26a deformed.

5 shows the arrangement of two such docking points, where docking point B is venting and the docking point C filling with one of the media mentioned the one that forms between the two boards Void serves in this area, as in FIG. 6 represented by the distance between the boards given is.

After screwing the inner board 13 onto the docking points and inserting the outer board will Tool closed, using the function of the hold-down device 23 the mentioned, controlled material flow and a plastic deformation of the sealing edge (see Fig. 6) is done. Now the cavity is over the docking system with water or the like. Pressure medium at approx. 10 to Filled 50 bar, which is due to the internal pressure in the area the docking points at the transition point between the recess 24 and the drawing ring collar 22a the compliant storage caused by the component 25 the socket 26 forms an embossed edge 28. Of the Movable die 21 is applied before the internal pressure towards the die to its end position move so that the final geometry due to the internal pressure the hood or the like. Workpiece and the mentioned Formation of the embossed edges in the area of the docking points be formed. After reaching the final shape, this will be Tool opened and the hood or the like workpiece removed, with the docking system from the Inner sheet or from the inner board along the embossed edges is torn out because the embossed edges 28 serve as shear edges. By removing the banjo bolts 27 can finally the funnel-shaped, held between the banjo bolts 27 and the bushings 26 Sheet metal sections of the inner board are removed.

As the above explanations show, this represents Docking system an effective and at the same time extremely simply designed measure for feeding the print medium represents, although it should not go unmentioned that at this stationary docking system, each filler neck 29, for example in the manner shown in Fig. 7 with the cavity of a hollow screw 27 in connection stands, which in turn is related to that between the two or more circuit boards formed cavity opens, is connected to a medium storage.

With the method according to the invention it is possible to use sheet metal different dimensions, surface finishes and / or steel grades including so-called "tailored blanks" and sandwich panels to be processed. When using KTL (dip coating) coated or lacquered boards, there is even another one Processing step, namely the subsequent one Paint.

It is also conceivable that individual parts of the hollow body conventionally manufactured by deep drawing and then according to the method of the invention connected to other boards and final calibrated will.

Overall, this results in the manufacture, in particular of large components when using the Invention a number of significant advantages:

By using the IHU process in the production Shape distribution of hollow bodies takes place and work hardening evenly over the entire component, which positively affects the surface quality, dimensional accuracy, Improvement of springback behavior as well - particularly important for large outer skin parts - affects the hail resistance. Due to the Integration of a variety of processing steps in a tool and the partial temporal overlay the processing steps shorten the manufacturing times as well as the logistics effort considerably. The investment costs are because of the saving of manufacturing facilities (e.g. joining devices), as well as the period for development and manufacture the tools shortened. Especially for car hoods or the like. "External parts" affects the touch or smooth deformation positive on the quality of the Outside surfaces, not to mention the tool wear is minimized.

Claims (43)

A method of manufacturing a hollow body such as an automobile hood, door or the like, in which at least two circuit boards, preferably made of sheet metal, held tightly against one another along an at least almost closed line, using the hydroforming (IHU) process, the hollow body is shaped and the interconnected boards are pushed through. Method according to Claim 1, characterized in that the boards are held tightly against one another in their edge regions and are interspersed in the region of their outer flanks. Method according to claim 1 or 2, characterized in that the clinching is carried out before, during and / or after the hydroforming. Method according to one of claims 1 to 3, characterized in that at least one further processing step is carried out during hydroforming. Method according to one of claims 1 to 4, characterized in that the further processing steps are carried out simultaneously, during, overlapping with and / or after the IHU process (es). Method according to one of claims 1 to 4, characterized in that the boards are angled or folded before being inserted into the IHU tool. Method according to one of claims 1 to 5, characterized in that the blanks are angled or folded in the IHU tool. Method according to one of claims 1 to 7, characterized in that the boards are fixed and / or sealed in their relative position by means of adhesive strips. Method according to one of claims 1 to 8, characterized in that the boards are flanged in the IHU tool. Method according to one of claims 1 to 9, characterized in that the blanks are cold welded in the IHU tool. Method according to one of claims 1 to 5 and 7 to 10, characterized in that the blanks are plastically pressed (cold deformed or welded) in the corner regions of their folds. Method according to one of claims 1 to 11, characterized in that blanks of different starting thicknesses, surface finishing and / or material types are used as the starting material. Method according to one of claims 1 to 12, characterized in that the hollow bodies are produced from an outer skin and an inner frame board. Method according to one of claims 1 to 13, characterized in that the internal high pressure is generated with the aid of a fluid. Method according to one of claims 1 to 13, characterized in that the internal high pressure is generated with the aid of a gas. Method according to one of claims 1 to 13, characterized in that the internal high pressure is generated with the aid of a foam. Method according to one of claims 1 to 16, characterized in that the forming medium is introduced into the hollow body by means of at least one pressure medium supply in the manner of a docking system provided with at least one lance, a mandrel or the like. Method according to claim 17, characterized in that the lances or the like of the docking system are pressed from the outside by at least one plate, preferably by the inner frame plate. Method according to one of claims 1 to 17, characterized in that the forming medium is introduced into the hollow body with the aid of a stationary docking system. Method according to claim 19, characterized in that the docking system is connected to the first (as the first) inserted circuit board, preferably to the inner circuit board, before further boards are inserted into the tool before it is closed. Method according to one of claims 1 to 20, characterized in that during the IHU process additional temporally and spatially controlled manufacturing steps, such as flanging, punching, pressing the flanges, folding, (pre) embossing and / or pre-cutting are carried out in one and the same tool will. A method according to claim 21, characterized in that the punching takes place "outwards". A method according to claim 21, characterized in that the punching takes place "inwards". Method according to claim 21, characterized in that the punching takes place "with the slug remaining on the component". Method according to one of claims 1 to 24, characterized by shaping the hollow body against a fixed boundary and / or movable counter pressure parts. Device for the production of hollow bodies, preferably components made of blanks, in particular for carrying out the method according to one of claims 1 to 25, characterized by a tool upper part (4) connected to a plunger (2) which can be moved up and down and a tool part (3) on a press table (3 ) attached lower tool part (5) as well as additional tools integrated therein. Apparatus according to claim 26, characterized in that the mutually facing surfaces of the upper tool part (4) and the lower tool part (5) form the negative shape of the component to be produced. Apparatus according to claim 26 or 27, characterized by a pressure medium supply (6) in the form of a docking system integrated in the lower tool part (5). Apparatus according to claim 28, characterized by an extendable and retractable lance (7) of the docking system (6) with a connection (8) to a medium store. Device according to claim 29, characterized in that the lance end (7) is designed in the form of a spike. Apparatus according to claim 28, characterized by a stationary docking system (25, 26, 27) with a connection (29) to a medium storage. Device according to one of claims 26 to 31, characterized by at least one hole device (9) integrated in at least one tool part (4, 5). Device according to one of claims 26 to 32, characterized by at least one additional tool integrated in at least one of the tool parts. Device according to one of claims 31 to 33, characterized by an at least two-part lower part of the tool which is overlapped laterally by the upper part of the tool (drawing die) (4) and which consists of a drawing ring (22) (additional tool) and a drawing die (21) guided therein. Apparatus according to claim 34, characterized by a collar (22a) of the drawing ring (22) directed towards the upper tool part (4). Apparatus according to claim 35 , characterized by at least one docking point (C) in the collar (22a) of the stationary drawing ring (22). Apparatus according to claim 36, characterized by at least one ventilation docking point (B) and at least one filling docking point (C). Device according to one of claims 31 to 37, characterized by a bushing (26) which is flexibly mounted in the collar (22a) and which has an internal thread for receiving a hollow screw (27) with a conically widening head (27a), the shape of which is a conical depression ( 26a) in the socket (26). Apparatus according to claim 38, characterized by an embossed edge (28) produced at the end transition between the bush (26) and the drawing ring collar (22a) by the internal pressure as a sheared edge on the board (13) lying thereon. Apparatus according to claim 33, characterized by at least one up and down movable stamp (15) for angling or folding in the upper tool part (4). Apparatus according to claim 40, characterized by at least one horizontally movable pressure die (16) in the lower part of the tool (5), which extends over the entire length of the board edge. Apparatus according to claim 40 or 41, characterized by punches (18) for clinching. Apparatus according to claim 42, characterized in that the joining stamps (18) are mounted in the contact stamp (s) (16) and can be moved relative to them.

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