EP1396297B1 - Device and method for deep-drawing - Google Patents

Description

The invention relates to a thermoforming device for deep drawing of metallic, sheet-metal blanks or blank, hereinafter referred to as blanks, essentially comprising a punch, a hold-down and a Thermoforming mold, and comprising at least one of the metallic, sheet-like Board acting, in particular individually adjustable, integrated in the stamp Drawing rod, according to the preamble of claim 1. The invention also relates to a method for deep drawing of metallic, sheet-like boards according to the preamble of claim 21.

Various thermoforming devices and methods are known in the art for deep drawing metallic, sheet-like boards known. The well-known Deep drawing devices and methods for deep drawing are also used for the production used by bodywork elements. It is doing while deep drawing boards with a high material strength (eg HSLA 340, DP600) or of boards with a compared to steel lower modulus of elasticity (e.g., aluminum) the geometric Accuracy by jumping back, rebounding or rebounding of the material or deteriorated by wrinkling. There are therefore pull rods in the Hold-down device of the deep drawing device or in the corresponding counter stop surface The thermoforming mold has been integrated to prevent springing back and wrinkling to reduce. The disadvantage here is that the formability is also reduced. So is z. B. from DE 199 53 751 A1 discloses a method and a device for passive Drawbar control for thermoforming tools known, in which case fixed in Hold-down or embedded in the die drawing rods are provided for Control of the sheet metal inlet serve in the drawing frame surface. It can do it such drawing rods are used, which are individually controllable and as needed can be retracted and extended during the drawing process. This was done the extension of the drawing rods so far active via separate operating mechanisms, so z. B. by hydraulic cylinders. To renounce this, or to the Reducing the cost of such active pull bar control becomes a passive one Drawbar control proposed, wherein the acting force on the Pinolenkraft is controlled. In the case of the passive pull bar control, the quill is in Downholder integrated and extension time or extension length are in Controlled dependence on the Pinolenkraft. To build the controller can while passive mechanical, pneumatic or hydraulic components be used.

US Pat. No. 6,276,185 B1 likewise discloses a deep-drawing device or a method known for deep drawing, wherein in the hold of the thermoforming device several drawing rods are provided for controlling the deep-drawing process. In this Trap to be processed boards are a two-stage deep drawing process subjected in the first step in particular the edge areas processed and in the second step, the deep drawing process is completed, and here too different drawing depths over the length may be provided.

In JP 58157531 a deep-drawing device is described which has an embossing stamp having as part of a thermoforming mold a door handle recess in a door panel of a Motor vehicle depresses. The door handle mold is part of the stamp for the entire door panel. So that in the edge area around the door handle recess no wrinkles or Waves when deep drawing occur, are movable around the die Hold-down arranged. These hold the door panel down before the Damping die dips into the door handle recess shape. The hold-downs themselves become by elastic elements, which are stored in the thermoforming mold, on the stamp pressed.

From the prior art is also known from DE 195 03 874 A1 a Deep-drawing tool with an integrated hold-down known. In this case the deep-drawing tool comprises a punch, a die and a hold-down, the hold-down fastened directly to the punch and throughout the entire Forming process is in contact with the sheet metal blank. The hold-down can do this be formed and arranged differently, can continue to be additional, with the hold-down in operative connection elements such as spacers, Brake elements or the like. Be provided.

Finally, from DE 195 04 649 C1 discloses a method and a drawing tool for Stretching of sheets is known in which the drawing process in substantially two Phases is divided to even in the inner region of the sheets a plastic Allow deformation, with a uniform material thickness be given should. The drawing process includes a first phase in which the sheet is transverse to Draw direction and the material of the areas away from the edge is pulled out, as well as a second phase, in which the material close to the edge is pulled out. It penetrates in the process first phase of the drawing process a Matrizen side at the edge of the die circulating provided web mounted in a punch side, at the edge of the drawing punch encircling trench and thereby brings sheet material from the middle, edge away area of the sheet out and thus these workpiece areas moved out.

Based on these known thermoforming devices and methods for Deep drawing of metal, sheet-like boards is the object of the invention underlying the known arrangements and methods while maintaining the previous advantages in such a way to improve or develop that a good deformability of the thermoforming circuit boards is given and still the geometric accuracy not by jumping back the material is worsened, i. Jumping back the material should be significantly reduced or possibly prevented.

The object is achieved with respect. According to the thermoforming device according to the invention by a thermoforming device with the features of claim 1. In this way, for the first time with simple means the possibility created to provide a good formability of the deep-drawing board and nevertheless to ensure that at the same time the geometric accuracy is not through jumping back the material is deteriorated because with the inventive Arrangement a jumping back of the material during deep drawing process considerably is reduced or prevented. The advantage of the arrangement according to the invention is esp. In the combination of a low inhibiting, the material flow controlling device at the beginning of the deep-drawing process in order to achieve a good formability with a significantly increased, the material flow inhibiting and reduced or inhibiting device at the end of the thermoforming process for Reduction or avoidance of a shape deviation by jumping back the deep-drawn board.

In the preferred embodiment of the present invention, an or several individually adjustable drawing rods directly in or on the stamp of Deep-drawing device integrated or arranged.

According to a further embodiment feature of the present invention is the at least one acting on the metallic, sheet-like board, in particular individually adjustable, directly in the stamp of the thermoforming device integrated pulling rod designed exchangeable.

It is recommended for a further embodiment feature of the present Invention, that the at least one on the metallic, sheet-like board acting drawing rod in each case located in a stamp of the thermoforming device Bag is arranged.

According to a further feature of the present invention it is provided that the Height of at least one acting on the metallic sheet-like board Pulling rod is adjustable.

According to a further embodiment feature, the present invention is preferred Invention for functionally correct action of the at least one drawing rod the metallic, sheet-like board an additional, acting on the drawing rod, Force resistance element provided. It is recommended that this on the Pulling rod acting, additional force resistance element formed adjustable is. The force acting on the pull rod, additional force resistance element can expedient by a spring element, in particular a gas spring element, be formed. Furthermore, for additional control of the respective drawing rod the deep drawing device be provided an active hydraulic force control.

According to a further feature of the present invention, the thermoforming mold in the essentially just be trained.

In an alternative embodiment, the thermoforming mold takes the place of each acting draw bar each have an additional cavity. there It is recommended that the at least one pulling rod at its for hollowing the Thermoforming side facing a convex and the cavity itself one corresponding concave configuration has. In a modified Execution is provided that the at least one pulling rod at its for Hollowing the thermoforming mold directed side a substantially rectangular and the cavity itself is also of a corresponding rectangular shape Embodiment has.

In a further advantageous embodiment of the invention, the two combined aforementioned embodiments, so that both concave / convex than also substantially rectangular cavities or drawing rods are present.

According to a further embodiment feature of the present invention is the at least one pulling rod each firmly in the on the stamp of the thermoforming device set pocket. It is recommended that to adjust the Height of the fixed in the bag located on the stamp puncture rod in the pocket inserted intermediate plates are formed.

In a modified embodiment of the present invention it is provided that in the additional cavity of the thermoforming mold for more precise adjustment of the Controlling the flow of material a movable insert is provided on the one Force resistance element acts. It can do this on the mobile use in the cavity of the thermoforming mold acting force resistance element is preferred be designed adjustable. Preference is given to the mobile use acting force resistance element by spring elements, in particular by Gas spring elements, formed, can continue to additional control of movable insert to be provided an active hydraulic force control.

With respect to the method, the object underlying the invention solved according to the invention by a method having the features of claim 21. This is the first time in procedural Realized that realizes a good formability of the deep-drawing board while still ensuring that at the same time the geometric accuracy is not deteriorated by jumping back the material. The the inventive method underlying advantage lies in particular in the nature of the variation of the material flow controlling deep drawing process.

In a preferred embodiment of the method according to the invention It is recommended that after 80 to 97% of the entire deep-drawing process the inhibiting, the material flow controlling device by attacking the drawing rods is significantly increased on the board.

According to another method feature of the present invention engages appropriate in the final part of the deep drawing process the material flow controlling device at a predetermined position on the board, such that the flow of material until the end of the deep drawing process significantly reduced or is inhibited.

According to a last feature of the present invention it is provided that the Material flow is inhibited in the final part of the deep drawing process.

Fig. 1

eine schematische Teil- Schnittansicht einer ersten Ausführungsform der erfindungsgemäßen Tiefziehvorrichtung mit geschlossenem Niederhalter in der Anfangsposition,

Fig. 2

eine schematische Teil- Schnittansicht eines Bereiches mit einem im Stempel integrierten Ziehstab der ersten Ausführungsform der erfindungsgemäßen Tiefziehvorrichtung gemäß Fig. 1;

Fig. 3

eine schematische Teil- Schnittansicht der ersten Ausführungsform der erfindungsgemäßen Tiefziehvorrichtung in der ersten Phase des Tiefziehvorganges;

Fig. 4

eine schematische Teil- Schnittansicht eines Bereiches mit einem im Stempel integrierten Ziehstab der ersten Ausführungsform der erfindungsgemäßen Tiefziehvorrichtung gemäß Fig. 3;

Fig. 5

eine schematische Teil- Schnittansicht der ersten Ausführungsform der erfindungsgemäßen Tiefziehvorrichtung in dem Moment des ersten Angreifens der Ziehstäbe an der Platine,

Fig.6

eine schematische Teil- Schnittansicht eines Bereiches mit einem Ziehstab der ersten Ausführungsform der Tiefziehvorrichtung in dem Moment des ersten Angreifens der Ziehstäbe an der Platine;

Fig. 7

eine schematische Teil- Schnittansicht der ersten Ausführungsform der erfindungsgemäßen Tiefziehvorrichtung in der Endphase des Tiefziehvorganges mit gehemmtem oder gestopptem Materialfluß;

Fig.8

eine schematische Teil- Schnittansicht eines Bereiches mit einem Ziehstab der ersten Ausführungsform der erfindungsgemäßen Tiefziehvorrichtung in der Endphase des Tiefziehvorganges;

Fig.9

eine schematische Teil- Schnittansicht eines Bereiches mit einem Ziehstab einer abgewandelten Ausführungsform der erfindungsgemäßen Tiefziehvorrichtung mit gehemmtem oder gestopptem Materialfluß in der Endphase des Tiefziehprozesses;

Fig. 10

eine schematische Teil- Schnittansicht eines Bereiches mit einem Ziehstab einer anderen abgewandelten Ausführungsform der erfindungsgemäßen Tiefziehvorrichtung in der Endphase des Tiefziehprozesses;

Fig. 11

eine schematische Teil- Schnittansicht eines Bereiches mit einem Ziehstab einer weiteren abgewandelten Ausführungsform der erfindungsgemäßen Tiefziehvorrichtung in der Endphase des Tiefziehprozesses; und

Fig. 12

eine schematische Teil- Schnittansicht eines Bereiches mit einem Ziehstab einer letzten abgewandelten Ausführungsform der erfindungsgemäßen Tiefziehvorrichtung in der Endphase des Tiefziehprozesses.

The invention is illustrated in the figures of the drawing in several embodiments. Show it:

Fig. 1

a schematic partial sectional view of a first embodiment of the deep drawing device according to the invention with closed downholder in the initial position,

Fig. 2

a schematic partial sectional view of a region with a stamping rod integrated in the stamp of the first embodiment of the deep drawing device according to the invention shown in FIG. 1;

Fig. 3

a schematic partial sectional view of the first embodiment of the deep drawing device according to the invention in the first phase of the deep drawing process;

Fig. 4

a schematic partial sectional view of a region with a stamping rod integrated in the stamp of the first embodiment of the deep drawing device according to the invention according to FIG. 3;

Fig. 5

a schematic partial sectional view of the first embodiment of the deep drawing device according to the invention at the moment of the first engagement of the drawing bars on the board,

Figure 6

a schematic partial sectional view of an area with a pulling rod of the first embodiment of the deep drawing device at the moment of the first engagement of the drawing bars on the board;

Fig. 7

a schematic partial sectional view of the first embodiment of the deep drawing device according to the invention in the final phase of the deep drawing process with inhibited or stopped material flow;

Figure 8

a schematic partial sectional view of an area with a pulling rod of the first embodiment of the deep drawing device according to the invention in the final stage of the deep drawing process;

Figure 9

a schematic partial sectional view of a region with a pulling rod of a modified embodiment of the deep drawing device according to the invention with inhibited or stopped material flow in the final phase of the deep drawing process;

Fig. 10

a schematic partial sectional view of a region with a pulling rod of another modified embodiment of the deep drawing device according to the invention in the final phase of the deep drawing process;

Fig. 11

a schematic partial sectional view of an area with a pulling rod of another modified embodiment of the deep drawing device according to the invention in the final phase of the deep drawing process; and

Fig. 12

a schematic partial sectional view of an area with a pulling rod of a last modified embodiment of the deep drawing device according to the invention in the final phase of the deep drawing process.

The deep-drawing device according to the invention is designated generally by 10. These Deep drawing device 10 is used for deep drawing of metallic, sheet-like boards, wherein the deep-drawing device 10 in particular for the production of Bodywork elements is used. The thermoforming device 10 comprises in essential, see, for. For example, Fig. 1 of the drawing, a stamp 12, a Downholder 13 and a thermoforming mold 14, and further comprises at least one acting on the metallic, sheet-like board 11, preferably individually adjustable, pulling rod 15.

It is inventively provided that the at least one on the metallic, sheet-like board 11 acting, preferably individually adjustable Pulling rod 15 is arranged directly on the punch 12 of the thermoforming device 10. By This arrangement is achieved that the arranged directly on the punch 12 respective pulling rod 15 at a predetermined time during the Deep drawing process on the board 11 attacks. The advantage of the invention Arrangement is esp. In the combination of a small inhibitory, the Materialfluß controlling device at the beginning of the thermoforming process in order Achieving good formability with a significantly increased, the material flow controlling device at the end of the deep drawing process to reduce or Avoiding a spring back of the deep-drawn board 11th

In the illustrated in FIG. 1 of the drawing thermoforming device 10 is to a flat or preformed board 11 placed on the thermoforming mold 14 and the Downholder 13 is closed. In the illustrated embodiment, the Hold-down 13 controlled by sleeves 23, where the holddown 13 set is. The thermoforming mold 14 is arranged on a spacer 24, which in turn on a here only schematically indicated press table 25 is located. The Stamp 12 is located on a plunger, designated 22, which determines the pulling force, e.g. one here schematically indicated double-acting press device weiterergibt. It but is also a use of the inventive arrangement in other than the shown press arrangements, z. B. single-acting presses, etc., intended.

Hereinafter, first, the deep-drawing device 10 and then described the inventive method. In the present case are, see again z. As shown in FIG. 1, exactly two individually adjustable drawbars 15 directly arranged on the punch 12 of the thermoforming device 10. The two on the metallic, sheet-like board 11 acting, preferably individually adjustable, directly on the punch 12 of the thermoforming device 10 arranged pulling rods 15 are formed exchangeable, furthermore, the two drawing rods 15 are each in a located on the punch 12 of the thermoforming device 10 pocket 16th arranged, see for example, also Fig. 2 of the drawing. The height of the on the metallic, sheet-like board 11 acting pull rod 15 is present adjustable to change the position of the attack on the board 11 can. The shape of the drawing rod 15 can have any suitable geometry.

In the z. B. in Figs. 1 to 10 illustrated embodiments is for functionally appropriate action of the two drawing rods 15 on the metallic, sheet-like board 11 an additional, acting on the respective drawing rod 15, Force resistance element 17 is provided, see, for. B. Fig. 2. This additional Force resistance element 17 is designed to be adjustable and is present formed by a spring element, in particular a gas spring element. It can but other solutions are provided here. Optionally, it can be used for additional adjustment of the respective drawing rod 15 of the thermoforming device 10 a be provided active hydraulic power control.

In the embodiments illustrated in FIGS. 1 to 8, the thermoforming mold 14 formed substantially flat. It is according to the invention but also provided, see the embodiments according to FIGS. 9 to 12 of the drawing, that the thermoforming mold 14 at the location of the respective acting drawing rod 15 respectively an additional cavity 18 has. It can, see the embodiment As shown in FIG. 9, the respective drawing rod 15 at its to the cavity 18 of Deep-drawing mold 14 directed side a convex and the cavity 18 itself one have corresponding concave configuration. Furthermore, see the Embodiments according to FIGS. 10 to 12, the respective drawing rod 15 at its to the cavity 18 of the thermoforming mold 14 side facing a substantially rectangular and the cavity 18 itself also a corresponding kind have rectangular configuration.

In the embodiment according to FIG. 11, the drawing rod 15 is fixed in each case the stamp 12 of the thermoforming device 10 located pocket 16 set. In This case can be provided that to adjust the height of the fixed in the the stamp 12 located pocket 16 specified pulling rod 15 in the pocket 16th inserted intermediate plates are formed, this embodiment is in the Figures of the drawing not shown. Furthermore, an embodiment with or possible without pockets, where the drawing rods without exchange possibility on Stamp are arranged or integrated in the stamp.

In the embodiment according to FIG. 12 of the drawing is in the additional Hollow 18 of the thermoforming mold 14 for more precise adjustment of the control of Material flow a movable insert 20 provided on the one Force resistance element 21 acts. The on this mobile use 20 acting force resistance element 21 is formed adjustable and is in the present case by spring elements, in particular by gas spring elements formed. However, other solutions can also be provided here. Optionally while for additional control of the movable insert 20 an active be provided hydraulic power control.

The process according to the invention will now be described below. This is characterized in that at the beginning of the deep-drawing process to increase the Formability of the board 11 a low inhibiting, controlling the flow of material Device is applied to the board 11, that at a predetermined Time of the deep-drawing process, the inhibiting, controlling the flow of material Device is significantly increased by attacking the drawing rods 15 on the board 11 and that in the final part of the deep drawing process, the material flow controlling means for minimizing a spring-back of the board 11 is increased is maintained. It access in the illustrated embodiment Beginning of the thermoforming process, the drawing rods 15 not on the board 11, see 1 and 3, at this time or in this phase, the board 11th but already on the punch 12 in the recess 26 of the thermoforming mold 14th drawn. The control of the material flow takes place via the force on Hold-down 13, about spacers between downholder and thermoforming mold or optionally via further drawing rods not shown here in the region of the hold-down 13th

At the beginning of the thermoforming process so low inhibiting, the Material flow controlling device applied to the board 11 to the Deformability of the board 11 to increase. At a predetermined time of Deep drawing process, preferably after 80 to 97% of the entire deep-drawing process the drawing rods 15 will attack on the surface of the board 11, see the Fig. 5 of the drawing, d. H. At this time, the inhibitory, the material flow controlling device by attacking the drawing rods 15 on the board 11 clearly elevated. In FIG. 6, the time of the first contact of the drawing rod 15 is to shown with the board 11. In the final phase of the thermoforming process engage the drawing rods 15 in a predetermined position on the board 11, and the flow of material is greatly reduced or until the end of the deep-drawing process inhibited, see Fig. 7. By an increased stretching of the material in this phase the deep drawing process is therefore a jumping back of the finished component after a removal from the thermoforming mold 14 is reduced or avoided, it is a such action particularly suitable for forming hat-shaped areas. When engaging the drawing rods 15 on the board 11 is the movement of the drawing rods 15 in the pockets 16 of the punch 12 opposite to the direction of movement of the punch 12. In the end position of the punch 12, the pulling rod 15 is almost completely in the pocket 16 of the punch 12. By different designs the drawbar height, these are not in the full height in the pockets, so that the drawing rods 15 on the board 11 attack, see Fig. 7 and Fig. 8.

In the embodiments according to FIGS. 1 to 8, the thermoforming mold 14 is flat educated. In the embodiments according to FIGS. 9 to 12, the Deep-drawing mold 14 an additional cavity 18, wherein different here Geometries with respect to the drawing rods 15 and 18 corresponding to the cavity selected can be. The material flow is through this training in the final Part of the deep drawing process additionally inhibited. If in this case the drawing rods 15 at attack the board 11, the material is in this cavity 18 of the thermoforming mold 14, see FIG. 10. The flow of material is inhibited when the distance SDB Drawing rod 15 - cavity 18 is smaller than the original thickness S0 of the board 11, or reduced if the distance SDB pulling rod 15 - cavity 18 is equal to or greater than the original thickness S0 of the board 11 is. This also applies to the Embodiment according to FIG. 11.

By the deep-drawing device 10 according to the invention or the inventive Method is compared to conventional deep-drawing devices with drawbars or the conventional method, a significant increase in the formability of the Material is reached and at the same time a jumping back of the material is minimized. The attachment of the respective drawing rod 15 according to the invention directly to the Stamp 12 can easily and inexpensively on the punch 12 a Deep-drawing device 10 are integrated.

As already mentioned, the illustrated embodiments are only examples Realizations of the invention, this is not limited thereto, but rather still many modifications and training possible. In particular the directly on the punch 12 arranged pulling rod 15 in other ways be determined this, continue to be conceivable, in particular modifications of the Deep drawing process forming process steps.

Claims (24)

1. Deep-drawing device (10) for deep drawing metallic, sheet-like blanks (11), essentially comprising a punch (12), a hold-down (13) and a deep-drawing die (14), and comprising at least one in particular individually adjustable drawing rod (15) acting on the metallic, sheet-like blank (11), characterized in that the at least one, in particular individually controllable drawing rod (15) acting on the metallic, sheet-like blank (11) is arranged directly on the punch (12) of the deep-drawing device (10) in such a way that, at the start of the deep-drawing operation, the blank (11) is drawn via the punch (12) into an aperture (26) of the deep-drawing die (14), but the drawing rod (15) does not act on the blank (11).
2. Deep-drawing device according to Claim 1, characterized in that one or more adjustable drawing rods (15) are arranged directly on the punch (12) of the deep-drawing device (10).
3. Deep-drawing device according to Claim 1 or 2, characterized in that the at least one, in particular individually adjustable drawing rod (15) acting on the metallic, sheet-like blank (11) and arranged directly on the punch (12) of the deep-drawing device (10) is designed to be interchangeable.
4. Deep-drawing device according to one of Claims 1 to 3, characterized in that the at least one drawing rod (15) acting on the metallic, sheet-like blank (11) is arranged in each case in a pocket (16) located in the punch (12) of the deep-drawing device (10).
5. Deep-drawing device according to one of Claims 1 to 4, characterized in that the height of the at least one drawing rod (15) acting on the metallic, sheet-like blank (11) is adjustable.
6. Deep-drawing device according to one of Claims 1 to 5, characterized in that, in order that the at least one drawing rod (15) acts on the metallic, sheet-like blank (11) in a functionally correct manner, an additional force-resisting element (17) acting on the drawing rod (15) is provided.
7. Deep-drawing device according to Claim 6, characterized in that the additional force-resisting element (17) acting on the drawing rod (15) is designed to be adjustable.
8. Deep-drawing device according to Claim 7, characterized in that the additional force-resisting element (17) acting on the drawing rod (15) is formed by a spring element, in particular a pneumatic spring element.
9. Deep-drawing device according to one of Claims 6 to 8, characterized in that an active hydraulic power control system is provided for the additional adjustment of the respective drawing rod (15) of the deep-drawing device (10).
10. Deep-drawing device according to one of Claims 1 to 9, characterized in that the deep-drawing die (14) is of essentially flat design.
11. Deep-drawing device according to one of Claims 1 to 9, characterized in that the deep-drawing die (14) has a respective additional cavity (18) at the location of the drawing rod (15) acting in each case.
12. Deep-drawing device according to Claim 11, characterized in that the at least one drawing rod (15) has a convex configuration on its side directed towards the cavity (18) of the deep-drawing die (14), and the cavity (18) itself has a corresponding concave configuration.
13. Deep-drawing device according to Claim 12, characterized in that the at least one drawing rod (15) has an essentially rectangular configuration on its side directed towards the cavity (18) of the deep-drawing die (14), and the cavity (18) itself likewise has a corresponding rectangular configuration.
14. Deep-drawing device according to Claim 12 or 13, characterized in that the deep-drawing die has concave, convex and/or essentially rectangular cavities (18), and the at least one drawing rod (15) has a corresponding configuration.
15. Deep-drawing device according to one of Claims 1 to 14, characterized in that the at least one drawing rod (15) is in each case firmly secured in the pocket (16) located on the punch (12) of the deep-drawing device (10).
16. Deep-drawing device according to Claim 15, characterized in that distance plates inserted into the pocket (16) located fixedly on the punch (12) are formed for setting the height of the drawing rod (15) firmly secured in the pocket (16).
17. Deep-drawing device according to one of Claims 11 to 16, characterized in that a movable insert (20), on which a force-resisting element (21) acts, is provided in the additional cavity (18) of the deep-drawing die (14) for the more accurate setting of the control of the material flow.
18. Deep-drawing device according to Claim 17, characterized in that the force-resisting element (21) acting on the movable insert (20) in the cavity (18) of the deep-drawing die (14) is designed to be adjustable.
19. Deep-drawing device according to Claim 18, characterized in that the force-resisting element (21) acting on the movable insert (20) is formed by spring elements, in particular by pneumatic spring elements.
20. Deep-drawing device according to one of Claims 17 to 19, characterized in that an active hydraulic power control system is provided for the additional setting of the movable insert (20).
21. Method of deep drawing metallic, sheet-like blanks (11), in which the blank (11) to be processed is clamped in place in a deep-drawing device (10) via a hold-down (13) and a corresponding abutment surface of the deep-drawing die (14), and the material flow is essentially controlled via drawing rods (15) acting on this blank (11), characterized in that a small restraining force controlling the material flow is applied to the blank (11) at the start of the deep-drawing operation for increasing the deformability of the blank (11), in that the restraining force controlling the material flow is markedly increased at a predetermined instant of the deep-drawing operation by the drawing rods (15) acting on the blank (11), and in that, during the final part of the deep-drawing operation, the force controlling the material flow is maintained at an increased level for minimizing springback of the blank (11), the drawing rods (15) not acting on the blank (11) at the start of the deep-drawing operation.
22. Method according to Claim 21, characterized in that, after 80 to 97% of the entire deep-drawing operation, the restraining force controlling the material flow is markedly increased by the drawing rods (15) acting on the blank (11).
23. Method according to either of Claims 21 and 22, characterized in that, during the final part of the deep-drawing operation, the force controlling the material flow acts on the blank (11) at a predetermined position in such a way that the material flow is essentially reduced or restrained up to the end of the deep-drawing operation.
24. Method according to one of Claims 21 to 23, characterized in that the material flow is additionally restrained during the final part of the deep-drawing operation in addition to the application of the force controlling the deep-drawing operation.

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