EP2512702B1 - Method and device for producing a half-shell part - Google Patents

Description

The invention relates to a method for producing a half-shell part with a drawing die and a drawing die, the drawing die being inserted into the drawing die in a single work step, a blank being preformed into a sheet metal blank with at least one base section, at least one frame section and optionally a flange section, wherein an excess of material is introduced either into the bottom section and the frame section and / or the optional flange section of the sheet metal blank during the preforming with the drawing die, and the sheet metal blank is finished molded into a half-shell part and calibrated. The invention also relates to a device for producing a half-shell part with a drawing die and a drawing die.

Closed or open hollow profiles are usually used as structural elements in automobile construction. These are increasingly being assembled from half-shell parts, whose cross-sections and material thicknesses are specially adapted to the respective application.

Boards are typically deep-drawn to produce the half-shell parts. During deep drawing, tensions are inevitably introduced into the half-shell parts, which lead to springback after the final molding. The Springing back of the half-shell parts, however, makes it difficult, for example, to position the half-shell parts precisely in a die for welding the half-shell parts to form a closed hollow profile.

In the DE 10 2007 059 251 A1 it has therefore been proposed to first pre-form a sheet metal blank from the board in a first device, which has an excess of material in the bottom section compared to the half-shell part to be produced. Then this Sheet metal blank finished in a further device to form a half-shell part, the excess material present in the base section being displaced into the other sections of the sheet metal blank. This can reduce the amount of springback. However, two devices and two work steps are necessary to obtain the desired half-shell part.

From the DE 198 53 130 A1 a method is also known with which partial sections of a half-shell part, in which both convex and concave structures are present, can be deep-drawn with improved quality. For this purpose, a spring-loaded slide is provided in the drawing die. During the downward movement of the drawing die, the blank in the subsection in question is first formed between the drawing die and the corresponding surface of the slide before the board as a whole is deep-drawn. This is to prevent excess material in certain areas. The known method only allows the shape retention of sections of the half-shell part to be improved.

The state of the art ( US 2002/0148272 A1 ) furthermore discloses a method and a device for deep drawing of metal sheets for producing a finished product, in which a metal sheet is inserted into a forming tool, which has a stamp and a die, and wherein the stamp consists of at least two independent segments and the metal sheet first is preformed by the first segment and then brought into its final shape by means of the second segment.

Out AT 504 783 A4 A method is known in which the sheet metal blank is first preformed by a first stroke of the molding tools with the sheet metal holder open, before it is brought into its final shape by clamping the molding tools after clamping in the sheet metal holder. Finally describe JP 63-080928 A and JP 2008-284576 A likewise methods and devices for deep drawing a sheet metal blank.

Starting from the prior art mentioned above, the present invention was therefore based on the object of specifying a method and a device for the reliable and cost-effective production of high-quality half-shell parts.

With regard to the method, this object has been achieved according to a first teaching of the invention in that the sheet metal blank is trimmed in the single step, preferably using a cutting edge arranged on the punch.

The preforming and / or the final shaping can be carried out as a cold forming step or as a hot forming step. During hot forming, steel blanks are usually heated and formed to temperatures above A _c1 , preferably above A _c3 . Structural transformation into austenite during hot forming is desired in order to take advantage of the better forming properties of this structure and to permit subsequent hardening, for example by converting the austenite into martensite or other structures.

Either in the bottom section and in the frame section when producing flangeless half-shell parts or in the optional flange section of the sheet metal blank when producing flange-connected half-shell parts, there is therefore more material than in the corresponding area of the half-shell part. This excess material can be displaced into the other sections during the final shaping and calibration, which induces compressive stresses in the entire half-shell part, which are in the plastic range, and thus the springback after deep drawing can be reduced or suppressed. The method according to the invention thus leads to half-shell parts which are distinguished by a high degree of dimensional accuracy, ie small tolerances.

In a first embodiment of the method, the use of a drawing punch is provided, which has at least one floor punch that can be positioned above in the direction of the drawing die and a corresponding floor punch receptacle. With the base punch arranged in the projecting position, the excess material is introduced either into the base section and the frame section or the optional flange section of the sheet metal blank during the preforming of the sheet metal blank. With such an at least two-part drawing die, an excess of material can be formed in the sheet metal blank in a process-reliable manner during the preforming. The production of a drawing die with a base die that can be positioned above is also associated with only a small outlay and thus low costs.

A next embodiment of the method provides that the sheet metal blank is finished molded and calibrated by moving the base stamp into the base stamp receptacle as soon as the base stamp has placed on the sheet metal blank lying against the drawing die. The sheet metal blank can thus be held in a particularly simple manner on the drawing die by the base stamp, so that the preformed sheet metal blank can be prevented from slipping during the final shaping and calibration. By placing the base stamp on the sheet metal blank lying against the drawing die, it is also possible at a very early stage of the final forming and Calibration of the material flow can be controlled in a targeted manner so that a springback-free half-shell part can be provided.

The sheet metal blank is trimmed according to the invention in a single step. The production of a high-quality, trimmed half-shell part in a single step enables shorter cycle times. On the other hand, a single device can be used. As a result, the process can be made more economical.

The sheet metal blank is preferably trimmed using a cutting edge arranged on the punch. The cutting edge can be formed on the drawing die itself. Alternatively, however, a cutting plate fastened to the drawing punch, in particular also movably, can be provided, which has the cutting edge. By using a separate insert, e.g. the fact that the cutting edge and the remaining areas of the drawing die are subject to different wear are taken into account.

A further embodiment provides that the cutting edge is brought into contact with the sheet metal blank at the same time as the base die is placed on the sheet metal blank lying against the drawing die. The cutting edge thus comes into contact with the sheet metal blank at a moment when the preforming has largely been completed. The cutting edge is then used to suppress a further flow of material into or out of the drawing die. By introducing excess material during preforming, the The cutting edge can also be brought into contact with a section of the sheet metal blank which is possibly still exposed to slight tensile loads, so that the sheet metal blank can be separated from the waste at a precisely defined point.

The method according to the invention can also be developed by pressing excess material from the bottom section of the sheet metal blank into the frame section and / or the optional flange section of the sheet metal blank during the final shaping and calibration. There is therefore not only a displacement within the area into which the excess material was introduced during preforming, but also in the adjacent frame section and / or the optional flange section, so that the dimensional accuracy of the half-shell part can be further improved overall.

The dimensional accuracy of the half-shell part to be produced can be increased in a further embodiment of the method in that the sheet metal blank is compressed using a compression surface at least in a frame section, preferably also in a base section. The upsetting causes the undesirable inhomogeneous stress and strain distributions associated with deep drawing to be superimposed and thereby specifically aligned so that they do not cause unwanted springback. In particular, by upsetting over the entire cross-sectional length, half-shell parts can be produced which have a very high dimensional accuracy in all sections.

A compression surface adjoining the cutting edge is preferably used for this purpose, so that the cut surface of the sheet metal blank can also be smoothed with the compression surface. In particular, if a frame section of the sheet metal blank is to be compressed which does not directly adjoin the cut surface, for example in the production of flange-clad half-shell parts, the cutting edge and compression surface can also be arranged separately from one another.

Another embodiment of the invention provides that the blank is held with a hold-down device at least at the beginning of the preforming. This largely prevents the formation of wrinkles during deep drawing, particularly in the case of thin blanks. In addition, the material flow into the drawing die can be controlled with the hold-down device.

In a further development of the method, a flangeless half-shell part is produced. Flangeless half-shell parts can be connected with an I-joint to form a closed hollow profile that has no disruptive, protruding sections. In addition, weight savings can be achieved in this way.

Alternatively, however, a half-shell part with a flange can also be produced. The flange provides a flat surface with which the half-shell part can be easily welded onto flat components, for example. Furthermore, a flange can provide a sufficiently large area for gluing the half-shell part to other components.

According to a second teaching of the invention, the above-mentioned object has been achieved by a device which has a drawing die, a drawing die and means for moving the drawing die into the drawing die, with a circuit board being positionable between the drawing die and the drawing die and the die being used for the die The blank can be preformed into a sheet metal blank, the drawing die has means for introducing excess material either into a base section and a frame section and / or an optional flange section of the sheet metal blank and the sheet metal blank can be finished and calibrated into a half-shell part, characterized in that means for trimming, in particular at least one cutting edge arranged on the punch is provided. With the device according to the invention, the forming from a blank to a high-quality half-shell part is thus made possible in a single tool, thereby achieving significant cost savings. The means for introducing an excess of material can be made available within the framework of a device that changes the shape of the drawing die. For example, a membrane that can be bulged with a pressure medium is suitable for this.

A simple first embodiment of the device, however, provides a base stamp which can be positioned in the direction of the drawing die and a corresponding base stamp receptacle, by means of which excess material can be introduced into the sheet metal blank during preforming. The production of such a drawing die is associated with only a small outlay, so that such a device is very inexpensive.

According to the invention, means for trimming, in particular at least one on Drawing punch arranged cutting edge, provided. This also enables trimming to be carried out using the same device, so that there are further cost advantages and time savings.

The device can also be designed in such a way that the drawing die has a franking assigned to the cutting edge of the drawing die. When trimming the sheet metal blank, the waste can be displaced into this clearance, so that a particularly smooth cut surface can be achieved.

If, according to a further embodiment of the device, the depth of the franking corresponds at least to the board thickness of the board to be formed, jamming of the waste can be prevented and the process according to the invention can be made more reliable.

Furthermore, a further development of the device, in which the drawing die has an inlet contour, for example an inlet rounding, facilitates the material flow into the drawing die. An inlet contour also has the advantage that it causes the cutting edges to self-center when they are placed on them. The fillet fillet is preferably assigned to the franking.

A further embodiment of the device provides that the cutting edge is at a distance from a counter-cutting edge arranged on the drawing die, in particular on the franking, in the deep-drawing direction or is arranged at the same height in the position of the drawing die completely retracted into the drawing die.

If a pressure load on the sheet metal blank is to be largely avoided, the counter cutting edge of the franking can also be arranged at the same height as the cutting edge of the drawing die.

In a manner comparable to the cutting edge, the counter-cutting edge can be formed on the drawing die itself or on a counter-cutting plate which is possibly movably attached to the drawing die.

With a cutting edge that is spaced apart in the deep-drawing direction, the sheet metal blank located in the space between the punch and the die can be subjected to a pressure load during the final shaping and calibration, so that the sheet metal blank is compressed. In this way, the undesirable inhomogeneous stress and strain distributions that are present after the drawing process can be superimposed and converted into newly aligned stresses that suppress unwanted springback of the half-shell part, i.e. its dimensional accuracy can be improved. The compression that occurs over the entire cross section leads to a state of stress that causes plastic flow in the entire cross section of the half-shell part.

Another development of the invention provides a compression surface of the drawing die which adjoins the cutting edge. In this way, the sheet metal blank can also be deliberately compressed on the cut surface, as a result of which a particularly smooth cut surface can be produced.

During deep drawing, the sections of the blank forming the frame section and / or the bottom section of the sheet metal blank may come into contact with the counter-cutting edge. In order to still guarantee a perfect material flow, the counter-cutting edge can be rounded in a further embodiment.

With the device according to the invention and the method according to the invention, half-shell parts can be produced which have a wall thickness W and in which the smooth cut proportion of the cut surfaces of the half-shell part is at least one third of the wall thickness W. Such half-shell parts can be welded particularly well in the I-joint on their cut surfaces with other components.

Further advantageous properties of the device can be found in the description of the method according to the invention.

Fig. 1a - c

ein erstes Ausführungsbeispiel einer erfindungsgemäßen Vorrichtung in verschiedenen Zuständen im Querschnitt;

Fig. 2

ein mit der in Fig. 1 gezeigten Vorrichtungen herstellbares Ausführungsbeispiel eines Halbschalenteil in perspektivischer Ansicht;

Fig. 3

die Schnittkante des in der Fig. 2 gezeigten Halbschalenteils im Querschnitt im Vergleich zur Schnittkante eines Halbschalenteils aus dem Stand der Technik;

Fig. 4a - e

einen Ausschnitt eines zweiten Ausführungsbeispiel einer erfindungsgemäßen Vorrichtung in verschiedenen Zuständen im Querschnitt;

Fig. 5a - c

ein drittes Ausführungsbeispiel einer erfindungsgemäßen Vorrichtung in verschiedenen Zuständen im Querschnitt;

Fig. 6

ein mit der in Fig. 5 gezeigten Vorrichtung herstellbares Ausführungsbeispiel eines Halbschalenteils in perspektivischer Ansicht;

Fig. 7a - c

ein viertes Ausführungsbeispiel einer erfindungsgemäßen Vorrichtung in verschiedenen Zustanden im Querschnitt und

Fig. 8

ein mit der in Fig. 7 gezeigten Vorrichtung herstellbares Ausführungsbeispiel eines Halbschalenteils in perspektivischer Ansicht.

The present invention will now be explained and illustrated in more detail with reference to a drawing showing exemplary embodiments. Show in the drawing

1a-c

a first embodiment of a device according to the invention in different states in cross section;

Fig. 2

one with the in Fig. 1 Devices shown manufacturing example of a half-shell part in a perspective view;

Fig. 3

the cutting edge of the in the Fig. 2 shown half-shell part in cross section compared to the cut edge of a half-shell part from the prior art;

4a-e

a section of a second embodiment of a device according to the invention in different states in cross section;

5a-c

a third embodiment of a device according to the invention in different states in cross section;

Fig. 6

one with the in Fig. 5 shown device producible embodiment of a half-shell part in a perspective view;

7a-c

a fourth embodiment of a device according to the invention in different states in cross section and

Fig. 8

one with the in Fig. 7 The device shown is an embodiment of a half-shell part in a perspective view.

The in the Fig. 1 The device shown has a drawing punch 1 which can be inserted into the drawing die 2 by means (not shown) for retracting, wherein it can be inserted into the die 1a to 1c positions shown in each case can be brought to a board 17th First to produce a sheet metal blank 5 and then a half-shell part 3 from the sheet metal blank 5.

The drawing die 1 has means for introducing excess material into a bottom section 4 of the sheet metal blank 5. It has a shape which can be changed by means of a base stamp 6 which is displaceably arranged in a base stamp receptacle 7. The edges 8 and 9 of the base die 6 facing the die 2 are rounded, so that the risk of kinking in the base portion 4 of the sheet metal blank 5 can be reduced.

In addition, a cutting edge 10 and a compression surface 11 directly adjoining this are formed on the drawing die 1. The upsetting surface 11 is essentially normal to the deep-drawing direction, i.e. aligned with the direction of insertion of the punch 1 into the die 2.

The drawing die 2 has a clearance 12 with an inlet rounding 13, which merges in steps into the frame section 15 of the drawing die frame section 16 to be produced, with a counter cutting edge 14 being formed. The franking 12 is so wide and deep that the board 17 is not hindered by the counter-cutting edge 14 during deep drawing.

First, according to that in the Fig. 1a shown a circuit board 17 between the die 1 and the die 2 arranged. The board 17 with the thickness P is held on the die 2 with a hold-down device 18. The bottom stamp 6 is in a direction of Drawing die 2 protruding position and has contact with the board 17th

With the means for retracting, not shown, which can be mechanical, pneumatic or hydraulic, pulling die 1 and die 2 are now in the in the Fig. 1b position shown brought. As a result, the board 17 is preformed into a sheet metal blank 5 with a frame section 15 and a bottom section 4. With a locking device, not shown here, the base stamp 6 is locked in the above position. However, it is also conceivable to hold the base punch 6 in the projecting position during the preforming, for example by means of a hydraulic or pneumatic cylinder or a spring.

The blank 17 is held by the holding-down device 18 on the drawing die 2 in such a way that on the one hand material can be drawn underneath, but on the other hand a bulging of the blank 17 and an associated wrinkle formation is avoided.

A sag to the nominal geometry of the floor is formed by the above floor punch 6, ie an excess material is introduced into the floor section 4 of the sheet metal blank 5. In the area of the inlet rounding 13, the sheet metal blank 5 lies against the clearance 12. The bottom stamp 6 sets in Fig. 1b shown position on the sheet metal blank 5 resting on the drawing die 2. At the same time, the cutting edge 10 of the punch 1 comes into contact with the sheet metal blank 5.

In this position, the locking of the bottom stamp 6 is now released, so that the bottom stamp 6 is pushed into the bottom die receptacle 7 when the punch 1 is retracted further into the die 2. In the case of a base stamp held in the projecting position with a hydraulic or pneumatic cylinder or a spring, it is sufficient that the means for retracting overcome the forces exerted by cylinders or springs.

The cutting edge 10 generates local stresses in the sheet metal blank 5 at a precisely defined point when the drawing die 1 and drawing die 2 are brought closer together, so that a crack is formed and the sheet metal blank 5 is trimmed. The waste 19, i.e. the unused material of the board 17 is displaced into the franking 12 of the die 2.

At the same time, as indicated by the arrow, the excess material generated during preforming is pressed into the entire sheet metal blank 5 by the base section 4 and the frame section 15. The stresses in the frame section 15 caused by the deep-drawing of the board 17 are thus specifically aligned. The springback of a half-shell part produced with this device is therefore at most slight and the dimensional accuracy of the half-shell part is increased.

In the in the Fig. 1c position shown, the punch 1 is fully retracted into the die. It is at bottom dead center. The drawing die 1 and the drawing die 2 essentially form a negative image of the inner or outer contour of the half-shell part to be produced.

The cutting edge 10 of the drawing punch 1 is arranged at a distance from the counter-cutting edge 14 assigned to the drawing die 2 in the deep-drawing direction. As a result, the frame section 15 can be compressed in the course of the final shaping and calibration. This also contributes to the high dimensional accuracy of the finished, in the Fig. 2 shown, flangeless half-shell part 3, which is characterized in particular by a relatively smooth cut surface 20.

With regard to the wall thickness W of the half-shell part 3 produced according to the invention, the smooth cut proportion of the cut surface is 20, as in FIG Fig. 3a represented schematically in comparison to a half-shell part from the prior art ( Fig. 3b ), more than a third. As a result, the half-shell part 3 shown can be welded in a particularly simple manner with further components, in particular also with a half-shell part produced with a comparable device, in an I-joint to form a closed hollow profile.

In the Fig. 4 a detail from an alternative embodiment of a device for producing a flangeless half-shell part 3 'is shown. This also has a die 1 'with a bottom die 6' and a die 2 '. The franking 12 'does not, however, pass in a step-like manner, but with a bevel 21' into the drawing die frame section 16 '.

The bevel 21 'has the advantage over the step-like transition that a counter cutting edge 14' is formed with an obtuse angle. Thus, their wear can be reduced will. It is also easier to manufacture. On the other hand, a step-like transition provides less resistance to the waste to be displaced during trimming and reduces the risk of the waste becoming jammed in the device. In addition, the bevel 21 'causes the cutting edge 10' to self-center during trimming.

Just like in the in the Fig. 1 In addition, the illustrated device has the cutting edge 10 'in the position of the drawing die 1' fully retracted into the drawing die 2 'in the deep-drawing direction lower than the counter-cutting edge 14' (cf. Fig. 4e ). As a result, in the Fig. 4 Device shown the entire cross section of the half-shell part 3 'compressed and converted into a plastic state.

Both a franking which has a bevel and a step-like franking can be combined with an arrangement of the cutting edge or the counter-cutting edge, in which the cutting edge and counter-cutting edge are at least at the same height in the position of the drawing die fully retracted into the drawing die.

With regard to the course of the forming from the plate 17 'via a sheet metal blank 5' to a half-shell part 3 ', reference is made to the explanations for Fig. 1 referred.

Finally shows Fig. 5 an embodiment of a device according to the invention with which a flange-connected half-shell part 3 ″ can be produced. Corresponding to the devices described above, the device shown in FIG Fig. 5 shown device a drawing die 1 "with a Floor stamp 6 "available, which additionally comprises a flange form stamp 33".

The drawing die 2 "has a drawing die bottom section 22" forming the base section 4 "of the sheet metal blank 5", a drawing die frame section 16 "forming the frame section 14" of the sheet metal blank 5 "and a drawing die flange section 24" forming the flange section 23 "of the sheet metal blank 5". The transition 25 ″ between the drawing die flange section 24 ″ and the drawing die frame section 16 ″ has an inlet fillet or a drawing radius.

Correspondingly, the bottom punch 6 "comprises a bottom section 26" and a bottom punch frame section 27 "and the flange die 33" comprises a flange die section 28 "with a cutting edge 10". This cutting edge 10 ″ is assigned an oversized bevel 21 ″ on the side of the drawing die 2 ″, which enables the cutting edge 10 ″ to self-center.

To produce the flanged half-shell part 3 ", as in the Fig. 5a shown, first the board 17 "between the die 1" and the die 2 ". The bottom die 6" of the die 1 "is in a projecting position in the direction of the die 2". The circuit board 17 ″ is held on the drawing die 2 ″ by a hold-down device 18 ″ outside the drawing die flange section 24 ″. The counter-holding section 30 ″ of the drawing die 2 ″, against which the board 17 ″ is held with the hold-down device 18 ″, is opposite Draw die flange section 24 "further from draw die bottom section 22".

By moving the die 1 "into the die 2", a sheet metal blank 5 "is first preformed, an excess material being generated in the flange section 23" of the sheet metal blank 5 "(cf. Fig. 5b ). The flange section 23 ″ of the sheet metal blank 5 ″ undergoes both a convex and a concave bend as a result of the offset planes of the drawing die flange section 24 ″ and the counter-holding section 30 ″ when the board is pulled.

Simultaneously with the placing of the base stamp 6 "on the sheet metal blank 5" resting on the die bottom section 22 ", the cutting edge 10" comes into contact with the sheet metal blank 5 ".

After the bottom punch 6 "has been placed on the sheet metal blank 5", only the flange die 33 'moves in the direction of the die 2 "and the sheet blank 5" is trimmed to a flange-shaped half-shell part 3 "with the cutting edge 10", finished formed and calibrated.

In the in Fig. 5c shown fully retracted into the die 2 "position of the die 1" can be seen that the flange die portion 28 "is formed as an offset contour of the die die portion 24". The offset has the value of the thickness P "of the plate 17", so that by the Excess material of the flange section 23 ″ is compressed. The offset between the die base section 26 ″ and the die bottom section 22 ″ corresponds to the thickness P ″ of the board 17 ″ Drawing die frame section 16 ″ and drawing die frame section 27 ″ is the offset by one in the Fig. 5 a - c not shown drawing gap increased to allow a material flow between the different sections of the sheet metal blank 5 "during the final forming and calibration.

The device can thus be used, for example, to produce a high-quality, trimmed half-shell part 3 ", which in the Fig. 6 is shown in perspective view.

Another variant of an embodiment of a device according to the invention shows Fig. 7 , with a further form of a flangeless half shell part 3 ''', as in Fig. 8 is shown in perspective view, can be produced.

The only difference to that in 5a-c The device shown is that the flange die 33 '''has a recess on the side with a cutting edge 10''', so that after trimming the sheet metal blank 5 '''and by further closing the device, the end section of the sheet metal blank 5''' is transferred into the recess. The flangeless half-shell part 3 '''is fully formed and calibrated.

The high dimensional accuracy of the flangeless or flanged half-shell parts 3, 3 ', 3 ", 3' '' is promoted by the fact that the entire cross section is converted into a plastic state by the compression and stresses can thereby be targeted.

Claims (16)

1. Method for producing a half-shell part with a drawing punch (1, 1', 1", 1"') and a drawing die (2, 2', 2", 2"'), wherein a single work step the drawing punch (1, 1', 1", 1"') is advanced into the drawing die (2, 2', 2", 2"'), a sheet metal blank (17, 17', 17", 17"') is preformed into a sheet metal raw part (5, 5', 5", 5"') with at least one base section (4, 4', 4", 4'"), at least one frame section (15, 15', 15", 15"') and optionally a flange section (23", 23"'), wherein during the preforming with the drawing punch (1, 1', 1", 1"') a material excess is introduced into the base section (4, 4', 4", 4'"), the frame section (14, 14', 14", 14"') and/or the optional flange section (23") of the sheet metal raw part (5, 5', 5", 5"'), and the sheet metal raw part (5, 5', 5", 5"') is finished to form a half-shell part (3, 3', 3", 3"') and is calibrated,
   characterised in that
   the sheet metal raw part (5, 5', 5", 5"') is trimmed in the single work step, preferably using a cutting edge (10, 10', 10", 10"') arranged on the drawing punch (1, 1', 1", 1"').
2. Method according to claim 1,
   characterised in that
   a drawing punch (1, 1', 1", 1"') is used, which comprises at least one base punch (6, 6', 6", 6"') positionable projecting in the direction in the direction of the drawing die (2, 2', 2", 2'") and a corresponding base punch receiver, and with the base punch (6, 6', 6", 6"') arranged in the projecting position the material excess is introduced during the preforming of the sheet metal raw part (5, 5', 5", 5"') into the base section (4, 4', 4", 4"') and the frame section (15, 15', 15", 15"') and/or the optional flange section (23", 23"') of the sheet metal raw part (5, 5', 5", 5"').
3. Method according to one of claims 1 and 2,
   characterised in that
   the sheet metal raw part (5, 5', 5", 5"') is finished and calibrated by advancing the base punch (6, 6', 6", 6'") into the base punch receiver (7, 7', 7", 7'") as soon as the base punch (6, 6', 6", 6'") has come to rest on the sheet metal raw part (5, 5', 5", 5"') abutting the drawing die (2, 2', 2", 2"').
4. Method according to any one of claims 1 to 3,
   characterised in that
   the cutting edge (10, 10', 10", 10"') is, at the same time as the placement of the base punch (6, 6', 6", 6'") on the sheet metal raw part (5, 5', 5", 5"') abutting against the drawing die (2, 2', 2", 2"'), brought into contact with the sheet metal raw part (5, 5', 5", 5"').
5. Method according to any one of claims 1 to 4,
   characterised in that
   during the finishing and calibration the material excess is forced from the base section (4, 4', 4", 4'") of the sheet metal raw part (5, 5', 5", 5"') into the frame section (15, 15', 15", 15"') of the sheet metal raw part (5, 5', 5", 5"').
6. Method according to any one of claims 1 to 5,
   characterised in that
   the sheet metal raw part (5, 5', 5", 5"') is compressed using a compression surface (11, 11", 11"'), in particular using a compression surface (11) abutting against the cutting edge (10), at least in a frame section (15, 15", 15"'), preferably also in a base section (4, 4", 4"').
7. Method according to any one of claims 1 to 6,
   characterised in that
   the sheet metal blank (17, 17', 17", 17"') is held at least at the start of the preforming with a hold-down device (18, 18', 18", 18"').
8. Method according to any one of claims 1 to 7,
   characterised in that
   a flange-free half-shell part (3, 3', 3"') or a flanged half-shell part (3") is produced from the sheet metal raw part (5, 5', 5", 5"').
9. Device for producing a half-shell part with a method according to any one of claims 1 to 8, with a drawing punch (1, 1', 1", 1"') and a drawing die (2, 2', 2", 2"'), wherein the device comprises means for advancing the drawing punch (1, 1', 1", 1"') into the drawing die (2, 2', 2", 2"'), a sheet metal blank (17, 17', 17", 17"') is positionable between the drawing punch (1, 1', 1", 1"' and the drawing die (2, 2', 2", 2"'), the sheet metal blank is preformable by the drawing punch into a sheet metal raw part (5, 5', 5", 5"'), the drawing punch (1, 1', 1", 1"' comprises means for introducing a material excess into a base section (4, 4', 4", 4'"), a frame section (15, 15', 15", 15"') and/or an optional flange section (23", 23"') of the sheet metal raw part (5, 5', 5", 5"'), and the sheet metal raw part (5, 5', 5", 5"') can finished and calibrated with the drawing punch (1, 1', 1", 1"' to form a half-shell part (3, 3', 3", 3"'),
   characterised in that
   means are provided for trimming, in particular at least one cutting edge (10, 10', 10", 10"') arranged on the drawing punch (1, 1', 1", 1'").
10. Device according to claim 9,
    characterised in that
    the drawing punch (1, 1', 1", 1"' has at least one base punch (6, 6', 6", 6'") that is positionable projecting in the direction of the drawing die (2, 2', 2", 2"'), and optionally has a corresponding base punch receiver (7, 7', 7", 7'").
11. Device according to claim 9,
    characterised in that
    the drawing die (2, 2', 2", 2"') has at least one clearance (12, 12', 12", 12"') associated with the cutting edge (10, 10', 10", 10"') of the drawing punch (1, 1', 1", 1"').
12. Device according to claim 11,
    characterised in that
    the depth (T, T', T", T"') of the clearance (12, 12', 12", 12"') corresponds at least to the sheet metal blank thickness (P, P', P", P"') of the sheet metal blank (17, 17', 17", 17"') to be formed.
13. Device according to one of claims 11 and 12,
    characterised in that
    the drawing die (2, 2', 2", 2"') has an in-flow rounded portion, in particular an in-flow rounded portion (13, 13', 13", 13"') arranged on the clearance.
14. Device according to ant one of claims 11 to 13,
    characterised in that
    the cutting edge (10, 10', 10", 10"') in the position in which the drawing punch is advanced fully into the drawing die is arranged in the deep drawing direction spaced from a counter-cutting edge (14, 14', 14", 14"') arranged on the drawing die (2, 2', 2", 2"'), in particular on the clearance (12, 12', 12", 12"'), or is arranged at least at the same height as the counter-cutting edge (14').
15. Device according to claim 14,
    characterised in that
    the counter-cutting edge (14, 14', 14", 14"') is rounded off.
16. Device according to any one of claims 9 to 15,
    characterised in that
    the drawing punch (1, 1', 1", 1"' comprises a compression surface (11, 11", 11"'), in particular a compression surface (11) directly adjoining the cutting edge (10).

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