EP1207974B1 - Deep-drawing method and deep-drawing die - Google Patents

Abstract

In order to provide a deep-drawing method, with which a drawn part is arranged in a deep-drawing die between a first deep-drawing die part and a second deep-drawing die part and is formed by way of relative movement of the deep-drawing die parts in relation to one another, which-particularly for carrying out several consecutive drawing processes-is more time and energy saving than the known deep-drawing methods it is suggested that a pressure variable with time during the drawing process be generated selectively at a limited pressure section of one of the deep-drawing die parts, this pressure pressing a section of the drawn part abutting on the pressure section against the respectively other deep-drawing die part.

Description

The present invention relates to a deep-drawing process in a drawn part in a deep-drawing tool between a first one Deep-drawing tool part and a second deep-drawing tool part arranged and by relative movement of the deep-drawing tool parts is formed to each other, as well as a deep-drawing tool according to the preamble of claim 13.

Such deep-drawing processes are known from the prior art (see e.g. EP-A-0 015 218).

In particular, there are deep-drawing processes with rigid deep-drawing tool parts known in which the drawing part from a drawing stamp drawn into a drawing body (also called a die) is, the edge of the drawing part by means of a drawing ring can be held.

To achieve the desired final shape of the drawn part it is often necessary to pull the drawn part in several successive pulls (also called pulls) deform.

However, the problem arises that the structure of the Drawn part material solidified during the first drawing process so that there is insufficient fluidity for another drawing process has what leads to the formation of cracks in the further Drawing process can result.

If the material of the drawn part is steel, then martensite is formed especially during the first drawing process, which the deformability of the drawn part in another Thermoforming process reduced.

In the known multi-pass deep drawing process is therefore the required deformability of the drawn part after the first Thermoforming process restored by the fact that Drawn part annealed at a temperature of approximately 1050 ° C , in particular the martensite, which is the first Thermoforming process has formed in more easily deformable Austenite is converted.

If more than two deep-drawing processes follow one another, this must be the case Annealing of the drawn part after each deep drawing process be repeated.

Because of the necessary before each further drawing process Annealing, cooling and washing processes are the well-known multi-pass Thermoforming process very time and energy consuming.

The present invention is therefore based on the object to create a deep-drawing process of the type mentioned at the outset, which - especially when performing several consecutive Pulling operations - saves time and energy than the well-known deep-drawing processes.

This task is carried out in a deep-drawing process with the characteristics of preamble 1 solved according to the invention in that at a limited pressure section of one of the deep-drawing tool parts selectively one that changes over time during the drawing process Pressure is generated, which one at the printing section adjacent section of the drawn part against each other deep-drawing tool part presses.

The solution according to the invention is based on the concept by targeting a limited area of the Drawn part during the drawing process for the deformation sufficient flow of the material of the drawn part even then to achieve if the flowability of the material of the drawn part per se based on the history of the material, for example due to a previous previous pull, is reduced.

In particular, with the deep-drawing process according to the invention then ensures the desired deformability of the drawn part if the drawn part is due to a previous one Contains martensite.

An annealing process and the cooling processes associated with the annealing process and washing operations can with the invention Thermoforming processes are also omitted if the thermoforming process is carried out several times.

The deep-drawing process according to the invention allows a special to achieve large draw ratios, and leads to higher ones Dimensional stability of the drawn parts.

In a preferred embodiment of the invention The method provides that the pressure at the printing section by means of a hydraulic or pneumatic pressure fluid is produced.

The hydraulic generation of pressure on one of the deep-drawing tool parts is in itself of the so-called Hydroforming process known in which the drawing body is provided with a membrane which during the forming process is put under water pressure. The drawing punch presses this process the drawn part against the membrane on the drawn body, the drawing part by the counteracting water pressure is reshaped. With this procedure, however, the whole Drawn part exposed to the same water pressure during the drawing process, while in the deep-drawing process according to the invention only on a limited pressure section of one of the deep-drawing tool parts a pressure is selectively generated which each limited portion adjacent to the printing section of the drawn part against the other deep-drawing tool part presses. In addition, in the hydroforming process water pressure acting on the drawing part during the drawing process constant.

A variant of the hydroforming process is the so-called Hydro-Mec process, in which the drawn part by a descending drawing stamp into pressurized water is pressed in without a membrane on the drawing body is provided. This method is also not selective Loading a limited portion of the drawn part with a pressure that changes over time during the drawing process intended.

Both in the hydroforming process and in the Hydro-Mec process becomes an even distribution of the hydraulic Pressure on the surface of the drawn part is sought, which the inventive concept, a limited section of To selectively apply an increased pressure to the drawn part, is just opposite.

In a preferred embodiment of the invention Thermoforming is provided that the pressure on the Printing section according to a predetermined temporal pressure curve is controlled and / or regulated.

This pressure curve can provide, for example, that the Pressure section without pressure during a first deformation phase is switched and that during a second deformation phase at the pressure section an increased, over the second deformation phase constant pressure is generated throughout. Such a Pressure curve is particularly easy to control and / or regulate.

Depending on the type of the drawn part and the desired deformation of the Drawn part can also any other time Pressure course controlled and / or regulated.

The deformability of the drawn part during the drawing process is particularly increased when the printing section is substantially parallel to the direction of drawing, along which the deep-drawing tool parts are moved relative to each other, aligned is. In this case it can be essentially parallel Areas of the drawn part that are aligned with the pulling direction aligned substantially parallel to the direction of pull Areas of the other deep-drawing tool part be pressed, what with the conventional deep-drawing process not possible. So in particular, essentially Side wall areas aligned parallel to the direction of pull of the drawn part can be formed particularly precisely.

The deep-drawing method according to the invention has proven particularly useful when only the frame of the drawn part during of the drawing process with the time-varying pressure is applied to the printing section. Such a deep drawing process is particularly suitable for the production of Gastronorm food containers that have a great depth and tend to have undesirable bulges in the frame area train which leads to poor stackability the food container can lead. By targeted application the frame of the Gastronorm food container during the pulling process with the time-varying pressure on the Print section can prevent such bulging or a bulge generated in a previous deep-drawing process be eliminated.

In a preferred embodiment of the invention Thermoforming is provided that the printing section is annular.

The type of generation of the time-varying pressure No details have so far been given for the printing section.

It can be provided that the pressure changes over time is generated by means of a pressure generating device which a chamber for receiving a pressurized fluid and an elastically deformable chamber wall for transmission of the pressure from the pressurized fluid on the drawing member.

Such a chamber can in particular have an annular shape his.

Such a chamber is particularly easy to manufacture, if they partially through the elastically deformable chamber wall and partly through a chamber boundary wall from one of the Different material of the elastically deformable chamber wall Material, preferably made of a metallic material, in particular made of aluminum, is limited.

Basically, the pressure section on the first deep-drawing tool part or arranged on the second deep-drawing tool part his. It can further be provided that both the first deep-drawing tool part as well as the second deep-drawing tool part in each case have one or more printing sections on which a time-varying one during the drawing process Pressure is generated.

In a preferred embodiment of the invention It is provided that the first deep-drawing tool part as a drawing body and the second deep-drawing tool part is designed as a drawing stamp and that the printing section is arranged on the drawing body.

Basically, the required to deform the drawn part Relative movement between the drawing punch and the drawing body both by moving the drawing punch as well a movement of the drawing body or also by a movement both deep-drawing tool parts are generated.

In a preferred embodiment of the invention It is intended that the drawing die be used during the deep-drawing process of the drawing process is stationary and the drawing body on the Drawing stamp is moved too.

As already stated, the deep-drawing process according to the invention is particularly advantageous if the drawn part at preformed in a first drawing operation and in a second Pulling process, in which the pressure changes over time the printing section is generated, is deformed. In this The case may be that required in the known deep-drawing processes Annealing and the resulting cooling and Washing operations are dispensed with before the second drawing operation, which is a significant time and energy saver brings.

The two drawing processes can be done in the same deep drawing tool be carried out, usually a replacement of the deep-drawing tool parts required between the drawing processes will be, or the two pulls will be in various deep drawing tools, which is suitable for Series production is recommended, since in this case the required drawing process, deep drawing tool parts in the respective deep-drawing tool can remain.

The present invention further relates to a deep-drawing tool, comprising a first deep-drawing tool part and a second Deep-drawing tool part, in which a drawn part by relative movement the deep-drawing tool parts can be formed relative to one another.

The present invention is based on the further object to create such a deep-drawing tool with the Help drawn parts - especially as part of a multi-pass Thermoforming process - time and energy saving than with known ones Thermoforming tools are deformable.

This task is performed on a deep-drawing tool with the characteristics of the preamble of claim 13 according to the invention solved that one of the deep-drawing tool parts a limited Has printing section on the during the drawing process selectively a time-variable pressure can be generated which is a portion abutting the printing portion of the drawn part against the other deep-drawing tool part presses.

The advantages of the deep-drawing tool according to the invention have been already above in connection with the invention Thermoforming process explained.

Special configurations of the deep-drawing tool according to the invention are the subject of claims 14 to 23, their advantages also already above in connection with special Embodiments of the deep-drawing method according to the invention explained have been.

Other features and advantages of the invention are the subject the following description and graphic representation of an embodiment.

Fig. 1

eine schematische perspektivische Darstellung eines Tiefziehwerkzeugs;

Fig. 2 - 5

schematische Querschnitte durch das Tiefziehwerkzeug aus Fig. 1 in vier verschiedenen Phasen eines herkömmlichen Tiefziehvorgangs;

Fig. 6 - 9

schematische Querschnitte durch ein Tiefziehwerkzeug, das einen Druckblasenring umfaßt, in vier verschiedenen Phasen eines erfindungsgemäßen Tiefziehvorgangs;

Fig. 10

eine schematische perspektivische Darstellung eines Ziehteils nach zwei Tiefziehvorgängen;

Fig. 11

eine Draufsicht auf einen Druckblasenring;

Fig. 12

einen Querschnitt durch den Druckblasenring aus Fig. 11 längs der Linie 12-12 in Fig. 11; und

Fig. 13

einen Querschnitt durch den Druckblasenring aus Fig. 11 längs der Linie 13-13 in Fig. 11.

The drawings show:

Fig. 1

is a schematic perspective view of a deep-drawing tool;

Figs. 2-5

schematic cross sections through the deep drawing tool of Figure 1 in four different phases of a conventional deep drawing process.

Fig. 6-9

schematic cross sections through a deep-drawing tool, which comprises a pressure bubble ring, in four different phases of a deep-drawing process according to the invention;

Fig. 10

is a schematic perspective view of a drawn part after two deep-drawing processes;

Fig. 11

a plan view of a pressure bubble ring;

Fig. 12

a cross section through the pressure bubble ring of Figure 11 along the line 12-12 in Fig. 11. and

Fig. 13

10 shows a cross section through the pressure bubble ring from FIG. 11 along the line 13-13 in FIG. 11.

The same or functionally equivalent elements are in all Figures with the same reference numerals.

A purely schematically shown in FIGS. 1 to 5, as The whole of a deep-drawing tool, designated 100, comprises one Base plate 102, one stationary on the top of the base plate 102 arranged drawing die 104, one the drawing die 104 ring-shaped sheet metal holder 106, which on a also the punch 104 ring-shaped surrounding support plate 108 is arranged, which by means of a (not shown) hydraulic movement device vertically movable quill 110 is worn, so that the support plate 108 with the sheet metal holder 106 arranged thereon along the vertical pulling direction 112 is movable.

The deep-drawing tool 100 further comprises one above the drawing die 104 and the sheet holder 106 arranged drawing body 114, which in turn has an annular pull ring base 116 and a drawing ring 118 held on the underside thereof includes.

The pull ring base 116 is at one on its top Holding plate 120 held by means of a (not shown) hydraulic movement device along the direction of pull 112 relative to the die 104 and the sheet metal holder 106 is movable.

The drawing body 114 forms the first deep-drawing tool part 122 the deep drawing tool 100; the drawing die 104 forms that second deep-drawing tool part 124 of the deep-drawing tool 100.

With the deep-drawing tool 100 described above a first deep-drawing process is carried out as follows:

First, the drawing body 114 and the sheet metal holder 106 by means of the respective hydraulic (not shown) Movement devices in their respective upper starting positions hazards.

In the upper starting position of the sheet metal holder 106 substantially flat top of the sheet metal holder 106 above the top of the punch 104.

In this position, a sheet metal blank or a circuit board 126, from which the drawn part is to be made, in the Thermoformed tool 100 inserted so that the edge of the board 126 rests on the sheet metal holder 106 (see FIG. 2).

The deep-drawing tool 100 is then closed by the drawing body by means of the hydraulic (not shown) Movement device from its upper starting position as far down along the direction of pull 112, until the bottom of the pull ring 118 at the top of the Board 126 abuts and the edge of the board 126 between the Drawing ring 118 and the sheet metal holder 106 is clamped (see Fig. 3).

In the subsequent process step, the board 126 becomes a drawn part 128 by means of the (not shown) hydraulic motion device the quill 110 with the support plate 108 arranged thereon and the sheet metal holder 106 and the drawing body 114 along the drawing direction 112 relative to the punch 104 down by the depth of draw can be moved, with the edge between the Drawing ring 118 and the plate holder 106 held circuit board 126 to the outer contours of the drawing ring 118 and the drawing punch 104 nestles (see Fig. 4).

After the desired drawing depth for the first deep drawing process is reached, the quills 110 with the arranged thereon Carrier plate 108 and the sheet holder 106 in their moved back to the upper starting position and the deep-drawing tool 100 opened by the drawing body 114 further along the drawing direction 112 moved up to its upper starting position will (see Fig. 5).

This is what is formed during the first deep-drawing process Pulling part 128 accessible from outside the deep-drawing tool 100 and can be taken from the same.

After this first deep-drawing process, the deep-drawn part has 128 have not yet received the desired final shape.

In the present example, the finished drawn part should have the shape of a Gastronorm food container that with a stacking heel running below its upper edge 130 132 is provided. In addition, the depth of the finished Food container may be greater than the depth of the drawn part 128 after the first thermoforming process, while the length and the The width of the finished food container is smaller in the frame area should be as in the one obtained by the first drawing process Draw 128.

To the required further transformations on the drawn part 128 will do the same to a second thermoforming process in a second deep-drawing tool 100 '(see FIG. 6) subjected.

The basic principle of the second deep-drawing tool 100 'corresponds Structure of the first deep-drawing tool described above 100, the drawing punch 104 and the drawing body 114 'are shaped accordingly to the desired reshaping of the drawn part 128.

The drawing body 114 'of the second deep-drawing tool further comprises 100 'a pressure generating device designated as a whole by 134 to generate a variable pressure.

The device 134 in turn comprises a pressure bubble ring 136, which is in an annular recess 138 on the inside the drawing ring base 116 is included and a has annular pressure bubble chamber 140 by a Chamber wall 142 made of an elastically deformable material, for example made of a polyurethane.

Open into the pressure bubble chamber 140 through the chamber wall 142 guided fluid supply lines 144, via which the pressure bubble chamber 140 a fluid under pressure, for example a hydraulic oil from a fluid pressure pump (not shown) is feedable.

With the second deep-drawing tool described above 100 ', a second deep-drawing process is carried out as follows:

First, the second deep-drawing tool 100 'is opened by the drawing body 114 'and the sheet holder 106 in their upper Starting positions are brought (see Fig. 6). Since that Drawn part 128 is already pre-deformed by the first deep-drawing process is the top of the sheet holder 106 in the starting position below the top of the drawing die 104 may be arranged.

Then that obtained from the first deep drawing process Deep-drawn part 128 inserted into deep-drawing tool 100 ' and placed on the sheet holder 106.

The second deep-drawing tool 100 'is then closed by the pulling body 114 'along the pulling direction 112 downwards is moved until the underside of the drawing ring 118 on the Bottom of the edge 130 of the drawn part 128 abuts and Edge of the drawing part 128 between the drawing ring 118 and the Sheet holder 106 is clamped.

Then a first deformation phase is carried out, by the quill 110 with the support plate arranged thereon 108 and the sheet metal holder 106 together with the drawing body 114 ' along the drawing direction 112 relative to the drawing punch 104 be moved down until the remaining drag a distance h is (see Fig. 7). During this first Deformation phase, the pressure bubble ring 136 is depressurized, that is, the fluid pressure pump is switched off or the fluid supply lines 144 are through a (not shown) Check valve separated from the fluid pressure pump, see above that the fluid located in the pressure bubble chamber 140 under is no higher than atmospheric pressure.

As soon as the remaining draw path corresponds to the distance h, the fluid in the pressure bubble chamber 140 is increased Pressure p is applied by the fluid pressure pump in operation taken and / or the check valve between the fluid pressure pump and opening the fluid supply lines 144. The elastically deformable chamber wall 142 of the pressure bubble ring 136 transmits the increased pressure of the fluid in the pressure bubble chamber 140 on the pressure bubble ring 136 Section of the frame 146 of the drawn part 128, which by the aligned substantially parallel to the direction of pull 112 Side walls of the drawing part 128 is formed so that this Section of frame 146 under increased pressure against the Drawing punch 104 is pressed.

Thus, the inside of the drawing part 128 facing the Bubble ring 136 as pressure section 148 of the drawing body 114 ', through which a bearing on the pressure section 148 Section of the drawing part 128 under one during the drawing process selectively changing pressure against the drawing die 104 is pressable.

During a second deformation phase, the drawn part becomes 128 finished by the quill 110 with the arranged thereon Carrier plate 108 and the sheet holder 106 together with the drawing body 114 'along the drawing direction 112 relative to the Pull punch 104 can be moved down until the desired one Drawing depth for the second deep drawing process has been reached (see Fig. 8).

By applying the frame 146 of the drawn part 128 with the pressure p through the pressure section 148 of the Drawing body 114 'reaches a sufficient amount of material when the drawing part 128 is deformed along the drawing direction 112 flows downward to form the stack paragraph 132, without cracks appearing on the drawn part 128.

Furthermore, by applying the frame 146 with the increased Pressure p ensures that the length and width of the drawn part 128 in the frame area thereof to the desired Reduce values and bulge of the drawn part 128, which was created during the first deep-drawing process, disappears.

After reaching the desired drawing depth at the end of the second Deformation phase, the pressure bubble ring 136 is depressurized again switched by the fluid pressure pump switched off and / or the check valve between the fluid pressure pump and the fluid supply lines 144 closed to the pressure bubble ring 136 becomes.

The second deep-drawing tool 100 'is then opened, by the quill 110 with the support plate arranged thereon 108 and the sheet holder 106 moved into the upper starting position and then the drawing body 114 'further along the direction of pull 112 up to its upper starting position is driven so that the finished drawn part 128 accessible from outside the deep-drawing tool 100 ' and can be removed from the deep-drawing tool 100 ' (see Fig. 9).

The pulling part 128 now has the desired final shape of a Gastronorm food container (see Fig. 10).

11 to 13 show a preferred embodiment in detail a pressure bubble ring 136, as in the invention Thermoforming process can be used.

As best seen from the cross sections of FIGS. 12 and 13 the bladder ring 136 includes an outer ring 150 from an elastically deformable material, for example from Polyurethane, in which a chamber limiting ring 152, the for example made of a metallic material, in particular can consist of aluminum, is embedded.

The outer ring 150 is made by the chamber restriction ring 152 into a casting mold, the inner contours of which Corresponds to the outer contours of the outer ring 150, is introduced and the space between the mold and the chamber restriction ring 152 is poured out with polyurethane.

The inside of the chamber delimitation ring 152 is included provided a release agent so that the outer ring 150 made of polyurethane only on the outside of the chamber limiting ring 152 adheres while on the inside of the chamber restriction ring 152 the material of the outer ring 150 from the chamber restriction ring 152 can be lifted off.

At two diametrically opposite points of the Bubble ring 136 becomes the chamber restriction ring 152 from one connecting piece 154 each, for example made of steel, penetrates, which from the chamber boundary ring 152 to Outside of the outer ring 150 leads and on its outer End can be connected to a fluid supply line 144.

Through the connector 154 through the fluid supply line 144 fluid supplied into the space between the outer ring 150 and the chamber limiting ring 152 get inside the chamber limiting ring 152 and the material of the outer ring 150 from the chamber restriction ring 152 lift off so that 152 between the chamber delimitation ring and the outer ring 150 a pressure bubble chamber 140 is formed whose volume depends on the pressure under which the fluid is is dependent. If this pressure is low, the pressure bubble chamber points 140 only a small volume (according to the solid boundary line in FIGS. 12 and 13). is the pressure of the fluid high, so the volume of the increases Bladder chamber 140 accordingly (compare the broken ones Boundary lines in FIGS. 12 and 13).

The outer ring 150 of the pressure bubble ring 136 is made of polyurethane manufactured, so a hydraulic oil as a pressure fluid can be used to fill the pressure bubble chamber 140.

Alternatively, the outer ring 150 of the pressure bubble ring 136 made of natural rubber, so instead is as Pressurized fluid to use a castor oil, for example, since natural rubber is attacked by hydraulic oil.

Claims (23)

1. Deep-drawing method, in which a part (128) for drawing is disposed in a deep-drawing die (100') between a first deep-drawing die part (122) and a second deep-drawing die part (124) and formed through a movement of the deep-drawing die parts relative to one another,
   characterised in that a pressure which is variable in time during the drawing operation is selectively generated at a defined pressure portion (148) of one (122) of the deep-drawing die parts, which pressure presses a portion of the part (128) for drawing which lies against the pressure portion against the respective other deep-drawing die part (124).
2. Deep-drawing method according to Claim 1, characterised in that the pressure at the pressure portion (148) is generated hydraulically or pneumatically by means of a pressure fluid.
3. Deep-drawing method according to either of Claims 1 and 2, characterised in that the pressure at the pressure portion (148) is controlled and/or regulated according to a predetermined time-related pressure pattern.
4. Deep-drawing method according to any one of Claims 1 to 3, characterised in that the pressure portion (148) is oriented substantially parallel to the drawing direction (112) along which the deep-drawing die parts (122, 124) are moved relative to one another.
5. Deep-drawing method according to any one of Claims 1 to 4, characterised in that the part (128) for drawing has an edge (146), and that only the edge is subjected to the time-variable pressure at the pressure portion (148) during the drawing operation.
6. Deep-drawing method according to any one of Claims 1 to 5, characterised in that the pressure portion (148) is of annular construction.
7. Deep-drawing method according to any one of Claims 1 to 6, characterised in that the time-variable pressure is generated by means of a pressure-generating device (134) which comprises a chamber (140) for holding a pressurised pressure fluid and an elastically deformable chamber wall (142) for transmitting the pressure from the pressure fluid to the part (128) for drawing.
8. Deep-drawing method according to Claim 7, characterised in that the chamber (140) is of annular construction.
9. Deep-drawing method according to either of Claims 7 and 8, characterised in that the chamber (140) is defined partly by the elastically deformable chamber wall (142) and partly by a chamber boundary wall (152) of a material which is different from the material of the elastically deformable chamber wall (142), preferably of a metallic material, in particular of aluminium.
10. Deep-drawing method according to any one of Claims 1 to 9, characterised in that the first deep-drawing die part (122) is constructed as a drawing body (114') and the second deep-drawing die part (124) is constructed as a drawing punch (104), and that the pressure portion (148) is disposed at the drawing body (114').
11. Deep-drawing method according to Claim 10, characterised in that the drawing punch (104) is stationary during the drawing operation and the drawing body (114') is moved up to the drawing punch (104).
12. Deep-drawing method according to any one of Claims 1 to 10, characterised in that the part (128) for drawing is preformed in a first drawing operation and post-formed in a second drawing operation, in which the time-variable pressure is generated at the pressure portion (148).
13. Deep-drawing die, comprising a first deep-drawing die part (122) and a second deep-drawing die part (124), in which a part for drawing can be formed by a movement of the deep-drawing die parts relative to one another, characterised in that one (122) of the deep-drawing die parts has a defined pressure portion (148), at which a time-variable pressure can be selectively generated during the drawing operation, which pressure presses a portion of the part (128) for drawing which lies against the pressure portion against the respective other deep-drawing die part (124).
14. Deep-drawing die according to Claim 13, characterised in that the pressure at the pressure portion (148) can be generated hydraulically or pneumatically by means of a pressure fluid.
15. Deep-drawing die according to either of Claims 13 and 14, characterised in that the pressure at the pressure portion (148) can be controlled and/or regulated according to a predetermined time-related pressure pattern.
16. Deep-drawing die according to any one of Claims 13 to 15, characterised in that the pressure portion (148) is oriented substantially parallel to the drawing direction (112) along which the deep-drawing die parts (122, 124) can be moved relative to one another.
17. Deep-drawing die according to any one of Claims 13 to 16, characterised in that a part (128) for drawing, which has an edge (146), can be formed in the deep-drawing die (100'), and that only the edge can be subjected to the time-variable pressure at the pressure portion (148) during the drawing operation.
18. Deep-drawing die according to any one of Claims 13 to 17, characterised in that the pressure portion (148) is of annular construction.
19. Deep-drawing die according to any one of Claims 13 to 18, characterised in that the deep-drawing die (100') comprises a pressure-generating device (134) for generating the time-variable pressure, wherein the pressure-generating device (134) comprises a chamber (140) for holding a pressurised pressure fluid and an elastically deformable chamber wall (142) for transmitting the pressure from the pressure fluid to the part (128) for drawing.
20. Deep-drawing die according to Claim 19, characterised in that the chamber (140) is of annular construction.
21. Deep-drawing die according to either of Claims 19 and 20, characterised in that the chamber (140) is defined partly by the elastically deformable chamber wall (142) and partly by a chamber boundary wall (152) of a material which is different from the material of the elastically deformable chamber wall (142), preferably of a metallic material, in particular of aluminium.
22. Deep-drawing die according to any one of Claims 13 to 21, characterised in that the first deep-drawing die part (122) is constructed as a drawing body (114') and the second deep-drawing die part (124) is constructed as a drawing punch (104), and that the pressure portion (148) is disposed at the drawing body (114').
23. Deep-drawing die according to Claim 22, characterised in that the drawing punch (104) is stationary and the drawing body (114') is moved up to the drawing punch (104).

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