EP2107952B1 - Device for even stretch-forming of workpieces - Google Patents

Description

The invention relates to a device for the flat ironing of workpieces, with a tool upper part and a tool upper part engaging with the tool lower part.

From the general state of the art, the so-called Cyril-Bath method is known, in which a workpiece is clamped in a clamping device having at least two clamping elements and, if appropriate, formed with a forming tool, for example a deep-drawing tool. However, this method can also be used exclusively for the flat stretch drawing of sheets. The method of flat stretch drawing is used in particular for relatively flat workpieces in order to achieve sufficient solidification thereof.

The disadvantage of this method and the device used for this purpose, however, is the high technical complexity that is required for the hydraulics and their control or regulation and the measurement of force and displacement. This results in very high investment and maintenance costs. In addition, the known devices for performing the Cyril-Bath process are very large and require a lot of space.

From the generic DE 195 04 264 A1 are a method and a device for edge clamping in the forming sheet drawing known. To prevent the contact surfaces of the clamping frame parts must be exactly touched, the same are formed by end faces of beads, so that at the edge of the sheet only the areas of the end faces of the beads are created. The beads thus serve in this device solely and solely for clamping the sheet, which is formed during clamping by a separate tool, in particular a deep-drawing tool. Without such an additional deep drawing tool, the device described there could therefore not be used.

The DE 195 04 649 C1 describes a method and a drawing tool for ironing sheet metal. In this case, the drawing tool in the region of its outer periphery on a dipping into a trench of the counter tool web. By this combination of the web with the trench a desired flow of the material is to be achieved in certain phases of the deformation.

The DE 24 50 624 A1 describes a device for pressing deep, thin-walled container bottoms with large diameters, which has a tool insert and a counter-holder. The tool insert and the counterholder in turn have a multiple draw bead, which, similar to the DE 195 04 264 A1 , When deep drawing of the workpiece acts as a hold-down and it must muster very high hold-down forces.

Another device is from the DE 723 220 C known.

However, all of the known devices and methods are incapable of performing a flat stretch drawing of workpieces.

It is therefore an object of the present invention to provide a device for the flat stretch drawing of workpieces, which has a simple construction and a small size and is able to perform a flat ironing in an exact manner.

According to the invention, this object is achieved by the features mentioned in claim 1.

The forming beads of the upper tool part and the lower tool part ensure a simultaneous holding and pulling of the workpiece, so that even with a single-acting press in a train a flat ironing and optionally subsequently a forming of the workpiece can be performed without the need for additional tools are required. The Umformsicken so serve not only for holding, but for the simultaneous induction of a tensile force in the workpiece, which is responsible for the flat ironing. During the penetration of the Umformsicken into the corresponding recesses, the workpiece moves within a closed geometry of the Umformsicken. The workpiece is thus inventively drawn into this Umformsickengeometrie, wherein the tensile force is influenced by the geometry of the tool formed by the upper part of the tool and the lower tool part. Clamping of the workpiece, as is the case with devices known from the prior art, does not take place with the device according to the invention.

Due to the fact that the tool movement is induced by the movement of the press or of the press ram, advantageously no additional drive and only one tool are required for performing the flat stretch drawing, which leads to an extremely low control effort. Furthermore, the tool can be made very simple and compact and is thus produced in a cost effective manner.

The stretching operation thus takes place in one stroke and, if further forming is necessary or desired, can be preceded by the deep-drawing stroke or combined with a deep-drawing stroke, so that the high process times present in the previous methods can be considerably reduced. As the workpiece is dynamically held and pulled, the material can slide back into the tool during a subsequent drawing operation, so that tears in the workpiece can be avoided and a high quality is ensured.

Due to the simple structure, the investment costs are essentially limited to material and manufacturing costs, so that the device according to the invention can be realized considerably cheaper than known devices. In fact, savings of up to 90% can be achieved in terms of investment in tooling costs.

Due to the described simple design of the tool, this can be used without any changes for the hot forming and thus also heated for flat ironing certain materials.

Here, the principal advantages of the Streckziehens, namely an increase in the strength of the workpiece, obtained so that bulges prevented and, where appropriate, additional effects can be achieved.

Since the two tool halves, so the upper die and the lower tool part, never touch, no Touchieraufwand, so no adaptation of the tool surfaces to each other required. For the same reason, the maintenance effort is essentially limited to the cleaning of the tool.

A variation of the tensile force induced in the workpiece can be achieved according to the invention in that the forming beads of the upper tool part and / or the lower tool part are designed so that they engage with the recesses of the lower tool part and / or the upper part of the tool at different times.

In a very advantageous development of the invention can be provided that the Umformsicken and located between the Umformsicken recesses are arranged on two opposite sides of the upper tool part and the lower tool part. A device designed in this way has a very simple construction and can be used for the flat stretch drawing of workpieces in one direction.

Alternatively, it can be provided that the Umformsicken are arranged on a total of four sides of the upper tool part and the lower tool part, wherein in each case two of the four sides facing each other. By means of such a device can be a flat ironing stretch of the workpiece to achieve in two directions.

Alternatively, it can also be provided that the Umformsicken are arranged on three sides of the upper tool part and the lower tool part in triangular shape. Such an embodiment of the device can be used in triangular tools.

Another possibility is that the Umformsicken and located between the Umformsicken recesses are arranged in a circle on the upper tool part and the lower tool part.

In addition to these embodiments, arrangements of the Umformsicken on more than four sides of the upper tool part and the lower tool part are conceivable.

If the height of the Umformsicken 20 - 120 mm, so on the one hand, a sufficient penetration depth of the Umformsicken in the corresponding recesses and thus a correspondingly strong deformation of the workpiece to achieve a corresponding effect in the flat ironing guaranteed and it prevents the other that the Umformsicken due to too high a height of the same can bend.

In order to achieve a different degree of deformation over the surface of the workpiece, it may further be provided that the height of the Umformsicken varies over the length thereof.

One possibility for realizing the penetration of the Umformsicken at different times may consist in that the height of the Umformsicken on each side of the upper die and / or the lower die part is different, the height difference between adjacent Umformsicken is 5 - 30 mm.

For example, the Umformsicken can be higher on the outside of the upper tool part and / or the lower tool part as on the inside, so that first the outer portion of the tool comes into contact with the workpiece.

Alternatively, however, the Umformsicken on the inside of the upper tool part and / or the lower tool part may be higher than on the outside.

According to the invention it is provided that the edges of the Umformsicken facing the workpiece are provided with radii having a size of 1 - 20 mm, in particular from 2 - 10mm. The design of the radii of the workpiece facing edges of the Umformsicken has proved to be crucial in terms of Training of the tensile force induced in the workpiece exposed because smaller radii induce a higher forming force in the workpiece.

In order to make use of this effect, the invention provides that the forming bead, which first engages with the corresponding recess, has a smaller radius than the last forming bead engaging with the corresponding recess. As a result, a very high stress is induced in the workpiece as soon as the first forming bead penetrates.

If, in addition to the flat ironing, a further deformation of the workpiece is required or desired, then a deep-drawing tool can be arranged in a gap between the forming beads.

In this context, it can further be provided that in at least one of the recesses a spring-loaded hold-down element is arranged. Such spring-loaded hold-down elements improve the wrapping of the workpiece and thus ensure an improved forming process.

Further advantageous embodiments and developments emerge from the remaining subclaims. Embodiments of the invention are shown in principle with reference to the drawings.

Fig. 1

eine stark schematisierte Darstellung der erfindungsgemäßen Vorrichtung mit einem Werkzeugoberteil, einem Werkzeugunterteil und zusätzlich einem Tiefziehwerkzeug;

Fig. 2

eine erste Ausführungsform der erfindungsgemäßen Umformsicken in einem ersten Zustand;

Fig. 3

die Vorrichtung aus Fig. 2 in einem zweiten Zustand;

Fig. 4

die Vorrichtung aus Fig. 2 in einem dritten Zustand;

Fig. 5

eine zweite Ausführungsform der erfindungsgemäßen Umformsicken in einem ersten Zustand;

Fig. 6

die Vorrichtung aus Fig. 5 in einem zweiten Zustand;

Fig. 7

die Vorrichtung aus Fig. 5 in einem dritten Zustand;

Fig. 8

einen Schnitt durch eine der erfindungsgemäßen Umformsicken;

Fig. 9

eine perspektivische Darstellung einer der Umformsicken;

Fig. 10

eine Draufsicht auf die erfindungsgemäße Vorrichtung mit einer ersten Konfiguration der Umformsicken;

Fig. 11

eine Draufsicht auf die erfindungsgemäße Vorrichtung mit einer zweiten Konfiguration der Umformsicken;

Fig. 12

eine Draufsicht auf die erfindungsgemäße Vorrichtung mit einer weiteren Konfiguration der Umformsicken;

Fig. 13

eine Draufsicht auf die erfindungsgemäße Vorrichtung mit einer weiteren Konfiguration der Umformsicken;

Fig. 14

eine Draufsicht auf die erfindungsgemäße Vorrichtung mit einer weiteren Konfiguration der Umformsicken;

Fig. 15

eine Draufsicht auf die erfindungsgemäße Vorrichtung mit einer weiteren Konfiguration der Umformsicken;

Fig. 16

eine Draufsicht auf die erfindungsgemäße Vorrichtung mit einer weiteren Konfiguration der Umformsicken;

Fig. 17

eine Draufsicht auf die erfindungsgemäße Vorrichtung mit einer weiteren Konfiguration der Umformsicken;

Fig. 18

eine Draufsicht auf die erfindungsgemäße Vorrichtung mit einer weiteren Konfiguration der Umformsicken;

Fig. 19

eine Draufsicht auf die erfindungsgemäße Vorrichtung mit einer weiteren Konfiguration der Umformsicken;

Fig. 20

eine Draufsicht auf die erfindungsgemäße Vorrichtung mit einer weiteren Konfiguration der Umformsicken;

Fig. 21

eine Draufsicht auf die erfindungsgemäße Vorrichtung mit einer weiteren Konfiguration der Umformsicken;

Fig. 22

eine weitere Ausführungsform der erfindungsgemäßen Vorrichtung in einem ersten Betriebszustand;

Fig. 23

die Vorrichtung aus Fig. 22 in einem zweiten Betriebszustand;

Fig. 24

die Vorrichtung aus Fig. 22 in einem dritten Betriebszustand;

Fig. 25

eine weitere Ausführungsform der erfindungsgemäßen Vorrichtung in einem ersten Betriebszustand;

Fig. 26

die Vorrichtung aus Fig. 25 in einem zweiten Betriebszustand; und

Fig. 27

die Vorrichtung aus Fig. 25 in einem dritten Betriebszustand.

It shows:

Fig. 1

a highly schematic representation of the device according to the invention with a tool upper part, a lower tool part and in addition a deep-drawing tool;

Fig. 2

a first embodiment of the Umformsicken invention in a first state;

Fig. 3

the device off Fig. 2 in a second state;

Fig. 4

the device off Fig. 2 in a third state;

Fig. 5

a second embodiment of the Umformsicken invention in a first state;

Fig. 6

the device off Fig. 5 in a second state;

Fig. 7

the device off Fig. 5 in a third state;

Fig. 8

a section through one of the Umformsicken invention;

Fig. 9

a perspective view of one of the Umformsicken;

Fig. 10

a plan view of the device according to the invention with a first configuration of the Umformsicken;

Fig. 11

a plan view of the device according to the invention with a second configuration of the Umformsicken;

Fig. 12

a plan view of the device according to the invention with a further configuration of the Umformsicken;

Fig. 13

a plan view of the device according to the invention with a further configuration of the Umformsicken;

Fig. 14

a plan view of the device according to the invention with a further configuration of the Umformsicken;

Fig. 15

a plan view of the device according to the invention with a further configuration of the Umformsicken;

Fig. 16

a plan view of the device according to the invention with a further configuration of the Umformsicken;

Fig. 17

a plan view of the device according to the invention with a further configuration of the Umformsicken;

Fig. 18

a plan view of the device according to the invention with a further configuration of the Umformsicken;

Fig. 19

a plan view of the device according to the invention with a further configuration of the Umformsicken;

Fig. 20

a plan view of the device according to the invention with a further configuration of the Umformsicken;

Fig. 21

a plan view of the device according to the invention with a further configuration of the Umformsicken;

Fig. 22

a further embodiment of the device according to the invention in a first operating state;

Fig. 23

the device off Fig. 22 in a second operating state;

Fig. 24

the device off Fig. 22 in a third operating condition;

Fig. 25

a further embodiment of the device according to the invention in a first operating state;

Fig. 26

the device off Fig. 25 in a second operating state; and

Fig. 27

the device off Fig. 25 in a third operating state.

Fig. 1 shows a device 1 for the flat drawstretching of a workpiece 2 shown by a dashed line, for example a steel, aluminum or titanium sheet. The device 1 has a tool upper part 3 and a tool lower part 4 engaging with the tool upper part 3. The upper tool part 3 and the lower tool part 4 are movable relative to each other, wherein in the present case, the lower tool part 4 is rigid and the upper tool part 3 can be moved by means of a drive device, not shown, but known per se. Optionally, the tool lower part 4 could be movable and the upper tool part 3 could be rigid or both tool parts 3 and 4 could be movable relative to one another. The upper tool part 3 and the lower tool part 4 are preferably made of a suitable tool steel, but for small series can also be used plastic materials. Ceramics or suitable composite materials can also be used for the upper tool part 3 and the lower tool part 4. For a hot forming can be provided to heat the upper tool part 3 and / or the lower tool part 4.

The upper tool part 3 has in each case on at least two sides thereof a plurality of Umformsicken 5, which in the relative movement between the upper tool part 3 and the lower tool part. 4 engage in corresponding recesses 6 of the lower tool part 4. Conversely, the lower tool part 4 has a plurality of Umformsicken 7, which engage in respective recesses 8 of the upper tool part 3. In each case, the forming beads 5 and the recesses 8 of the upper tool part 3 and the Umformsicken 7 and the recesses 6 of the lower tool part 4 alternate. The Umformsicken 5 and 7 may be provided with a coating, for example, to influence the required forming forces.

In addition, at the in Fig. 1 illustrated embodiment of the device 1 in a space 9 between the upper die 3 and the lower die part 4, a deep-drawing tool 10 is arranged, which also consists of a tool upper part 11 and a lower tool part 12. The deep-drawing tool 10 may be formed in a manner known per se and, in particular, the deep-drawing tool 10 may also be dispensed with if the device 1 is used only for flat ironing of the workpiece 2 and no deep-drawing machining thereof is required. On the in Fig. 1 illustrated, but not designated gas springs of the upper tool 11 can of course be omitted.

In the FIGS. 2, 3 and 4 is a first embodiment of the upper tool part 3 and the lower die part 4 and in particular of the Umformsicken 5 and 7 thereof shown. It can be seen that the upper tool part 3 has a total of four Umformsicken 5a, 5b, 5c and 5d and located therebetween recesses 8a, 8b and 8c. The lower tool part 4 has three Umformsicken 7a, 7b and 7c and located therebetween recesses 6a, 6b and 6c. Here, between the innermost Umsummsicke 7c and one for placing the workpiece 2 serving Workpiece support 2a also has a recess, namely the recess 6c, provided, in which engages the innermost Umformsicke 5d. The Umformsicken 7 of the lower tool part 4 should be at least as high as the workpiece support 2a. In the case where the deep-drawing tool 10 is present, the workpiece support 2a serves as a forming die or forms the same.

The forming beads 5a, 5b, 5c and 5d of the upper tool part 3 are interpreted in the illustrated embodiment so that they go at different times with the recesses 6a, 6b and 6c of the lower tool part 4 in engagement. In a manner not shown, the Umformsicken 7 of the lower tool part 4 could be designed accordingly. This applies in principle for all embodiments of the device 1 described below, in which reference is made to a particular embodiment of the Umformsicken 5 of the upper tool part 3. In the in the FIGS. 2, 3 and 4 illustrated embodiment, the Umformsicken 5a and 5b of the upper tool part 3 on the outside thereof are higher than the Umformsicken 5c and 5d on the inside. As a result, the two outer Umformsicken 5a and 5b in front of the two inner Umformsicken 5c and 5d engage the workpiece. 2

As further in the Figures 2-4 can be seen, the workpiece 2 facing edges of the Umformsicken 5 and 7 are provided with radii whose size is in particular in a range of 1 - 20 mm, in particular 2-10mm. In order to induce a high tension in the workpiece 2 when the two first forming beads 5a and 5b penetrate into the workpiece 2, in the present case the forming bead 5a engaging first with the corresponding recess 6a has a smaller radius than the last with the corresponding recess 6c engaged forming bead 5d. The order of the different dimensioned radii of the Umformsicken 5 and 7 has a significant impact on the induced stress in the workpiece 2 and thus on the transformation of the same. The geometry of the Umformsicken 5 and 7 can be further adapted to the geometry and / or the material of the workpiece 2 to edit each workpiece 2 according to its requirements.

The movement of the workpiece 2 within the geometry of the Umformsicken 5 and 7 and its deformation can in the Figures 2-4 to be watched. Here, a gap with a width between 2 - 5 mm between the Umformsicken 5 and 7 and the corresponding recesses 6 and 8 has been found to be very well suited for the movement of the workpiece 2, this value of course of the thickness of the workpiece. 2 depends.

In the present case, the two outer Umformsicken 5a and 5b together with the workpiece 2 engage. However, an embodiment is also conceivable in which the outermost forming bead 5a penetrates into the workpiece 2 as the first and in particular in front of the adjacent forming bead 5b.

The height of the Umformsicken 5 and 7 is in particular 20 - 120 mm and may be different on each side of the upper tool part 3 and / or the lower tool part 4. The height differences between adjacent Umformsicken 5a - 5d or 7a - 7c can be between 5 and 30 mm. In the Figures 2-4 For example, the tool upper part 3 has four forming beads 5 and the tool lower piece 4 has three forming beads 7. The minimum number of Umformsicken 5 or 7 is two, more than eight Umformsicken 5 and 7 are not required, each between two Umformsicken 5 a recess 8 and between two Umformsicken 7 is a recess 6.

In the FIGS. 5, 6 and 7 an embodiment of the device 1 is shown, in which the Umformsicken 5d and 5c on the inside of the upper tool part 3 are higher than on the outside thereof. As a result, the inner Umformsicken 5d and 5c come before the outer Umformsicken 5b and 5a with the corresponding recesses 6 of the lower tool part 4 into engagement. The information regarding the height of the Umformsicken 5 and 7 and attached to the same radii can essentially the information on the embodiment of the FIGS. 2, 3 and 4 correspond, wherein the Umformsicken 5a - 5d of the upper tool part 3 have smaller radii than in the previous embodiment.

Alternatively to the in the Figures 2-4 or 5-7 illustrated embodiments, it is also possible to perform the Umformsicken 5 and 7 so that a central Umformsicke 5 or 7 first penetrates into the workpiece 2.

Fig. 8 shows a cross section through any of the Umformsicken 5 or 7. It can be seen that the Umformsicken 5 and 7 in the height direction have a substantially rectangular cross-section, which may be located on the workpiece 2 side facing the above-mentioned different radii. It has been found to be particularly suitable when the width of the Umformsicken is 10 - 40 mm.

In Fig. 9 an embodiment of one of the Umformsicken 5 or 7 is shown, in which the height varies over the length thereof. As a result, a different degree of deformation can be achieved over the surface of the workpiece 2, or certain areas can be shaped differently than other areas of the workpiece 2, as a result of which forming errors can optionally be avoided.

The FIGS. 10-21 show different embodiments of the arrangement of the Umformsicken 5 and / or 7 on the upper tool part 3 and / or the lower tool part 4. In the present case, each of the upper tool part 3 is shown with the Umformsicken 5, the arrangement is, of course, also for the Umformsicken 7 of the lower tool part. 4 ,

In the embodiment according to Fig. 10 the Umformsicken 5 and 7 and located between the Umformsicken 5 and 7 recesses 6 and 8 are arranged on two opposite sides of the upper tool part 3 and the lower tool part 4. The same applies to the embodiment of Fig. 11 in which the Umformsicken 5 and 7 and the recesses 6 and 8 on the longitudinal side instead, as in Fig. 10 , are arranged on the broad side of the upper tool part 3 and the lower tool part 4. Similarly, the embodiments of Figures 12 - 15 are formed, in which case the Umformsicken 5 and 7 and the recesses 6 and 8 are bent in the longitudinal direction thereof.

In the embodiments of the device 1 according to the FIGS. 16, 17, 18 and 19 are the Umformsicken 5 and 7 and located between the Umformsicken 5 and 7 recesses 6 and 8 arranged on a total of four sides of the upper tool part 3 and the lower tool part 4. In each case two of the four sides are opposite each other. Similar to the embodiments of the FIGS. 10-15 can here as well as straight over their length bent Umformsicken 5 and 7 and recesses 6 and 8 are used.

In the embodiment of the device 1 of Fig. 20 are the Umformsicken 5 and 7 and the recesses 6 and 8 to three Pages of the tool shell 3 and the lower tool part 4 arranged so that they form a triangular shape. A similar closed shape of the Umformsicken 5 and 7 is also in the embodiment of Fig. 21 recognizable, in which the Umformsicken 5 and 7 and the recesses 6 and 8 located between the same are arranged in a circle on the upper tool part 3 and the lower tool part 4. Of course, completely different, in particular adapted to the shape of the workpiece 2 arrangements of the Umformsicken 5 and 7 and the recesses 6 and 8 are conceivable.

In the FIGS. 22, 23 and 24 an embodiment of the device 1 is shown, in which between the Umformsicken 5 and the upper die 3 respective Unterlegplatten 13 are arranged, through which the penetration depth of the Umformsicken 5 can be influenced in the workpiece 2, if different levels Unterlegplatten 13 are used. Optionally, the shims 13 could also be provided on the lower tool part 4. Even without the shims 13, the Umformsicken 5 and 7 can be removably attached to the upper tool part 3 and the lower tool part 4.

Furthermore, the device 1 according to the FIGS. 22-24 a between the upper die 3 and the lower tool part 4 on the one hand and the workpiece support 2a arranged on the other hand, in particular by means of at least one gas spring sprung holding-down element 14 which is able to improve the looping of the workpiece 2. In a manner not shown may be provided in one or more of the recesses 6 and / or 8 such hold-down elements.

In the in the FIGS. 25, 26 and 27 illustrated embodiment of the device 1, in turn, the thermoforming tool 10 is provided, by means of which the workpiece 2 during its processing not only just stretched, but after the flat stretch-drawing additionally deep-drawn. In this connection, the forming die 5 closest to the deep-drawing tool 10 may be formed as a draw ring.

With reference to the Figures 2-4 and with reference to the FIGS. 5 to 7 described embodiments can with all embodiments of the FIGS. 10-21 be combined. In the embodiments according to the FIGS. 17 and 18 is particularly advantageous that is prevented by the cut corners between the individual Umformsicken 5 and 7, that the workpiece 2 between the upper die 3 and the lower tool part 4 tilt and thus can pinch the device 1.

Claims (13)

1. A device (1) for the even stretch-forming of workpieces (2), having a tool upper part (3) and a tool lower part (4) which engages with the tool upper part (3), which tool upper part and tool lower part can be moved relative to one another, wherein both the tool upper part (3) and the tool lower part (4) each have at least two mutually spaced forming beads (5, 7) on at least two sides in each case, which forming beads engage in respective corresponding cutouts (6, 8) in the tool lower part (4) or the tool upper part (3),
   wherein the forming beads (5, 7) of the tool upper part (3) and/or the tool lower part (4) are designed so that they engage with the cutouts (6, 8) of the tool lower part (4) and/or the tool upper part (3) at different times, characterised in that those edges of the forming beads (5, 7) which face the workpiece (2) are provides with radii which have a size of 1 - 20 mm, in particular 2 - 10 mm, and in that the forming bead (5, 7) which is first to engage with the corresponding cutout (6, 8) has a smaller radius than the forming bead (5, 7) which is last to engage with the corresponding cutout (6, 8).
2. A device according to Claim 1,
   characterised in that the forming beads (5, 7) and the cutouts (6,8) located between the forming beads (5, 7) are arranged on two opposing sides of the tool upper part (3) and the tool lower part (4) in each case.
3. A device according to Claim 1, characterised in that the forming beads (5, 7) and the cutouts (6, 8) located between the forming beads (5, 7) are arranged on a total of four sides of the tool upper part (3) and the tool lower part (4), wherein two of the four slides are opposite one another in each case,
4. A device according to Claim 1,
   characterised in that the forming beads (5, 7) and the cutouts (6, 8) located between the forming beads (5, 7) are arranged in the form of a triangle on three sides of the tool upper part (3) and the tool lower part (4).
5. A devise according to Claim 1,
   characterised in that the forming beads (5, 7) and the cutouts (6, 8) located between the forming beads (5, 7) are arranged in the form of a circle on the tool upper part (3) and the tool lower part (4).
6. A device according to one of Claims 1 - 5,
   characterised in that the height of the forming beads (5, 7) is 20 - 120 mm, therein the height of the forming beads (5, 7) alters over the length thereof.
7. A device according to one of Claims 1 - 6,
   characterised in that the height of the forming beads (5, 7) on each individual side of the tool upper part (3) and/or the tool lower part (4) is different, with the difference in height between mutually adjacent forming beads (5, 7) being 5 - 30 mm.
8. A devise according to one of Claims 1 - 7,
   characterised in that the forming beads (5, 7) on the outside of the tool upper part (3) and/or the tool lower part (4) are higher than on the inside, or in that the forming beads (5, 7) on the inside of the tool upper part (3) and/or the tool lower part (4) are hither than on the outside.
9. A device according to one of Claims 1 - 8,
   characterised in that the width of the forming beads (5, 7) is 10 - 40 mm.
10. A device according to one of Claims 1 - 9,
    characterised in that the forming beads (5, 7) are curved in the longitudinal direction.
11. A device according to one of Claims 1 - 10,
    characterised in that respective spacers (13) are arranged between the forming beads (5, 7) and the tool upper part (3) and/or the tool lower part (4).
12. A device according to one of Claims 1 - 11,
    characterised in that the forming beads (5, 7) are provided with a coasting.
13. A device according to one of Claims 1 - 12,
    characterised in that a deep-drawing tool (10) is arranged in a clearance (9) between the forming beads (5, 7), in that a spring-loaded holding-down element (14) is provided in at least one cutout (6, 8), and in that the forming bead (5, 7) which is closest to the deep-drawing tool (10) is constructed as a drawing ring.

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