US20160199898A1

US20160199898A1 - Stamping arrangement and use thereof

Info

Publication number: US20160199898A1
Application number: US14/913,624
Authority: US
Inventors: Albrecht Schneider
Original assignee: Individual
Current assignee: Individual
Priority date: 2013-08-23
Filing date: 2014-08-15
Publication date: 2016-07-14
Also published as: ES2549797T3; WO2015024645A1; EP2839897B1; EP2839897A1

Abstract

In a stamping arrangement, during stamping a stamping punch makes contact, in the region of a punch shoulder, with a holding plate or a pressure plate between the stamping punch and holding plate. The stamping punch has a punch head and the holding plate has a receptacle for the punch head. Means for fastening the punch head to the holding plate have a pocket made in the punch head, a clamping screw screwed into a threaded bore of the holding plate, a pressure piece arranged in the axial direction of the clamping screw between the latter and the pocket, and a holding screw for the pressure piece, wherein the holding screw passes through a bore of the clamping screw and is screwed with a threaded portion into a threaded bore of the pressure piece. With the clamping screw in a screwed-in position, areal contact is made, on a side of the pocket that faces away from the punch shoulder, between a conical portion of the pressure piece and a conical portion of the pocket, and the punch shoulder bears against the holding plate or the pressure plate, wherein a screw head of the holding screw is arranged with axial play with respect to the clamping screw.

Description

CROSS REFERENCE TO RELATED APPLICATIONS

This United States non-provisional application is the national stage of International Application No. PCT/EP2014/002241 filed on Aug. 15, 2014, which claims the benefit of priority to European Application No. EP 13181503.7 filed on Aug. 23, 2013, the entire disclosures of which are incorporated herein by reference.

FIELD OF THE INVENTION

The invention relates to a stamping arrangement having a stamping punch and a holding plate for the stamping punch.

BACKGROUND OF THE INVENTION AND RELATED ART

Stamping punches are used in so-called “prog dies” and “multiple die presses”. Tools of this type work as sets comprising, in some circumstances, a plurality of sister tools in multiple-die presses with high punching force.
The main field of application of such punching tools is automobile construction, in particular the construction of chassis and bodywork.
A “prog die” of this type, of small to medium size, has external measurements of about 1,600 mm×1,200 mm, comprising a multiplicity of forming punches, for instance about 20 forming punches. In this case, stamping punches are generally arranged spatially close together, surrounded by piping which serves to monitor the pressures of installed gas pressure springs by means of manometers built into the tool.
As a result of the ever more advancing use of high-strength sheets in automobile construction, the necessary stamping pressures, and thus also the stripping forces which act on the stamping punch and the anchorage thereof in its holding plate in the return and thus stripping operation, are increasing. In this context, a maximum load of these stripping forces of about 100 kN (10 tonnes) per forming punch can reasonably be assumed for the “prog die”. A stamping force of 1,000 kN (100 tonnes) is herein adopted as the basis. A stamping punch absorption system which is to be designed for this particular application must be able to absorb these tensile forces in the return or stripping operation with appropriate certainties.
A significantly reduced working life of the arrangement is obtained if a play-afflicted mounting of the stamping punch in the holding plate in the return or stripping operation has to be registered. In this case, very high bending and gravitational forces act on the connection of stamping punch and holding plate.
Furthermore, regard must be paid to the spatial relationships in the tool. The possibility must be given of being able to change the stamping punches in the cramped lateral working space brought about by the arrangement. In particular, this should be possible quickly and without removal of the holding plate in the event of wear or breakage of the punch.

OBJECT AND SUMMARY OF THE INVENTION

The object of the present invention is to provide a stamping arrangement in which the working life of the arrangement, due to a play-free mounting of the stamping punch in the holding plate in the return or stripping operation, is significantly high.
The object is achieved by a stamping arrangement which is configured according to the features of the invention disclosed herein.
The stamping arrangement according to the invention has a stamping punch and a holding plate for the stamping punch, wherein the stamping punch, in a stamping stroke, makes contact in the region of a punch shoulder with the holding plate, or with a pressure plate disposed between the stamping punch and the holding plate. The stamping punch has a punch head and the holding plate has a receptacle for the punch head. In addition, means for fastening the punch head to the holding plate are provided. These means have according to the invention:

- a pocket made in the punch head,
- a clamping screw screwed into a threaded bore of the holding plate,
- a pressure piece arranged in the axial direction of the clamping screw between the latter and the pocket,
- a holding screw for the pressure piece, wherein the holding screw passes through a bore of the clamping screw and is screwed with a threaded portion into a threaded bore of the pressure piece.

In this case, in a screwed-in position of the clamping screw, on a side of the pocket that is facing away from the shoulder, a conical portion of the pressure piece makes full-faced contact with a conical portion of the pocket. In this screwed-in position of the clamping screw, the punch shoulder bears against the holding plate or the pressure plate, and a screw head of the holding screw is arranged with axial play with respect to the clamping screw.
In this configuration of the stamping arrangement, in particular of the means for fastening the punch head to the holding plate, it is ensured that the stamping punch is pretensioned with its punch shoulder in a play-free manner against the holding plate or the pressure plate. In the stamping stroke, it is thus ensured that the stamping forces are transmitted between punch shoulder and holding plate or punch shoulder and pressure plate. The stamping pressure is thus not absorbed by the pressure piece. Related to the return stroke or stripping operation of the stamping punch, this has the result that the holding plate and the stamping punch are moved in a play-free manner, since this freedom from play is guaranteed by the inventive design and arrangement of the pressure piece. There is thus no play-afflicted connection present between holding plate and stamping punch and it is ensured that no loose connection between holding plate and stamping punch arises. A loose connection of this kind, which brings about an imprecise guidance of the stamping punch, would result in the stamping punch deforming or damaging the stamped sheet in the course of the return stroke or stripping operation. Apart from this, a play-afflicted connection of this kind leads to increased mechanical load upon the connection region of holding plate and stamping punch, resulting in a shorter working life. In particular, there is the danger of the stamping punch breaking in the region of the punch head.
Since the pressure piece does not make contact with a recess in the punch head, which recess passes fully through the punch head, but instead a pocket is provided in the punch head, increased forces can be transmitted via the punch head in the course of the return stroke or stripping operation.
In the stamping arrangement according to the invention, by means of the clamping screw, via the pressure piece, such a pretensioning can be generated between punch shoulder and holding plate or pressure plate, which pretensioning guarantees that the stamping punch, following a theoretically possible setting operation, is still firmly seated and thus no play can arise between punch shoulder and holding plate or pressure plate.
In order that the stamping punch can be removed, it is necessary to pull the pressure piece wedged in the pocket out of this pocket. This is realized on the basis of the inventively provided connection which the holding screw establishes between the clamping screw and the pressure piece. If the clamping screw is turned in the unscrewing direction, this leads to the axial play between the screw head in the holding screw and the clamping screw being reduced until the screw head of the holding screw bears against the clamping screw, and then, upon further unscrewing of the clamping screw, due to the form closure between the screw head of the holding screw and the clamping screw, the pressure piece is jointly moved, out of the clamping position with respect to the pocket.
Preferably, means for orienting the pressure piece in a rotational direction of the pressure piece relative to the conical portion of the pocket are provided. As a result, a loose precentering of the pressure piece is guaranteed, whereby it can be readily ensured that, upon the advancement of the clamping screw, the conical portion of the pressure piece makes full-faced contact with the conical portion of the pocket.
According to one embodiment, it is provided that the described arrangement for holding the stamping punch in the holding plate is doubly provided. Thus two pockets are made in the punch head, and a pressure piece cooperates with the respective pocket, and a clamping screw and a holding screw cooperate with the pressure piece. In this respect, reference is made to the preceding statements. In this case, in particular these pockets are identically configured, also these clamping screws are identically configured, also these pressure pieces are identically configured, and finally these holding screws are identically configured.
The stamping arrangement according to the invention is used, in particular, in a “prog die” or multiple die press, having a multiplicity of stamping and/or pressing tools, with a stripping force >50 kN, in particular in a multiple die press with a stripping force up to 100 kN.
Further features of the stamping arrangement according to the invention are shown and described hereafter in the description of exemplary embodiments of the invention, the accompanying drawing figures and the description of the drawing figures, wherein it is noted that all individual features and all combinations of individual features are to be considered various aspects and embodiments of the invention.

BRIEF DESCRIPTION OF THE DRAWING FIGURES

In the accompanying drawing figures, the invention is represented on the basis of various exemplary embodiments when used in a “prog die”, without the invention being restricted to these embodiments and use, and wherein like reference character in the various figures represent like or similar parts.

FIG. 1 represents a top view of a “prog die” fitted with a multiplicity of forming punches, of which three are stamping arrangements according to a first exemplary embodiment the invention.

FIG. 2 represents a stamping arrangement according to the invention in a three-dimensional view.

FIG. 3 represents the stamping arrangement according to FIG. 2 in an exploded representation.

FIG. 4 represents the stamping arrangement according to FIG. 2 in a view IV in FIG. 5.

FIG. 5 represents the stamping arrangement in a view V in FIG. 4.

FIG. 6 represents a section through the stamping arrangement according to the line VI-VI in FIG. 4.

FIG. 7 represents the region A according to FIG. 6 in enlarged representation, wherein in FIG. 7 a pressure piece of the stamping arrangement is illustrated in its clamping position.

FIG. 8 represents a section according to FIG. 7, illustrated with the pressure piece of the stamping arrangement having been moved out of a pocket.

FIG. 9 represents a holding plate of the stamping arrangement in a three-dimensional view.

FIG. 10 represents the holding plate in a view X according to FIG. 11.

FIG. 11 represents the holding plate in a view XI according to FIG. 10.

FIG. 12 represents the holding plate in a view XII according to FIG. 11.

FIG. 13 represents a stamping punch of the stamping arrangement in a three-dimensional view.

FIG. 14 represents the stamping punch in a view XIV according to FIG. 15.

FIG. 15 represents the stamping punch in a view XV according to FIG. 14.

FIG. 16 represents the stamping punch in a view XVI according to FIG. 14.

FIG. 17 represents the region B according to FIG. 15 in enlarged representation.

FIG. 18 represents the functional unit formed from a clamping screw, the pressure piece and a holding screw, in a three-dimensional representation.

FIG. 19 represents the functional unit in a view XIX according to FIG. 20.

FIG. 20 represents the functional unit in a view XX according to FIG. 19.

FIG. 21 represents the holding screw in a three-dimensional view.

FIG. 22 represents the holding screw in a view XXII according to FIG. 23.

FIG. 23 represents the holding screw in a view XXIII according to FIG. 22.

FIG. 24 represents the clamping screw in a three-dimensional view.

FIG. 25 represents the clamping screw in a view XXV according to FIG. 26.

FIG. 26 represents the clamping screw in a view XXVI according to FIG. 25.

FIG. 27 represents the pressure piece in a three-dimensional view.

FIG. 28 represents the pressure piece in a view XXVIII according to FIG. 29.

FIG. 29 represents the pressure piece in a view XXIX according to FIG. 28.

FIG. 30 represents for a second embodiment a modified stamping arrangement in a sectional representation according to FIG. 7.

FIG. 31 represents in a three-dimensional view the pressure piece shown in FIG. 30.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS OF THE INVENTION

FIG. 1 shows the top side of a “prog die” stamping unit 1 which is provided with a multiplicity of forming punches, specifically eighteen forming punches. These are mounted in a common unit, which, in small to medium size, has dimensions of about 1,600×1,200 mm. This stamping unit 1 is mainly used in automobile construction, in particular in the manufacture of chassis and bodywork.
From FIG. 1 it can be seen that the eighteen forming punches are arranged spatially close together, surrounded by piping 3, which serves to monitor the pressures of built-in gas pressure springs 4 by means of manometers built into the tool.
Three of the forming punches which are used in the stamping unit 1 are configured in accordance with the a first exemplary embodiment of a stamping arrangement 2 according to the invention.
This stamping arrangement 2 according to the first embodiment is illustrated in FIGS. 2 to 29.
The stamping arrangement 2 has a stamping punch 5 and a holding plate 6 for the stamping punch 5. The stamping punch 5 has a punch part 7, by means of which the actual stamping is realized, as well as a punch head 8 connected to the punch part 7. The punch head 8 is of plate-like configuration. On the side facing toward the punch head 8, the punch part 7 has a punch shoulder 9.
Between the stamping punch 5, specifically the punch shoulder 9, and the holding plate 6 is arranged a pressure plate 10. The pressure plate 10 has a long hole 11 which passes through it. On both sides of the long hole, the pressure plate is provided with recesses for the reception of screws 12, wherein the (non-illustrated) heads of these screws 12 are sunk in the region of the bottom side of the pressure plate 10. By means of these screws 12, the pressure plate 10 is fastened to the bottom side of the holding plate 6, specifically is screwed into the threaded bores 13 which are present there. The long hole 11 has such dimensions that the punch head 8 passes through the pressure plate 10 with low play in the two spatial coordinates running perpendicular to the direction of insertion of the punch head 2.
Viewed in the direction of stamping, the holding plate 6, the pressure plate 10 and the punch part 7 have an identical cross-sectional shape, namely in the form of a rectangle with beveled corners. The surface areas of holding plate 6 and pressure plate 10, viewed in the direction of stamping, are equal, while the surface area of the punch part 7 in this direction is smaller.
The holding plate 6 has in the region of the four corners bores for the reception of screws 14, wherein the respective screw head, on that side of the holding plate 6 that is facing toward the pressure plate 10, is sunk in a recess. By means of these screws 14, the holding plate 6 is connected to a base plate 15 of the stamping unit 1. Two dowel pins 16 mounted in the holding plate 6 serve for the guidance of the holding plate 6 in the positioning of the holding plate 6 with respect to the base plate 15. Correspondingly, the base plate 15 is provided not only with threaded bores for the screwing-in of the screws 14, but also with receptacles for the insertion of the dowel pins 16.
The holding plate 6 has two receptacles 17 and an intervening crosspiece 18. In this case, the receptacles 17 pass through the holding plate 6, while the crosspiece 18 extends only roughly over half of the thickness of the holding plate 6, in that region of the holding plate 6 that is facing away from the pressure plate 10. Correspondingly, the punch head 8 has two head portions 19, between which a recess 20 is formed. The respective head portion 19 is inserted into a receptacle 17 assigned thereto. In this case, the crosspiece 18 passes through the recess 20. Consequently the stamping punch 5 is positioned in the region of the punch head 8 in the two coordinate directions perpendicular to the direction of stamping, largely without play, in the receptacles 17 of the holding plate 6, and is also oriented with respect to the crosspiece 18 of the holding plate 6.
In that position of the stamping punch 5 in which it is inserted in the holding plate 6 and in which the stamping punch 5 passes with the punch head 8 through the pressure plate 10 and the pressure plate 10 is screwed to the holding plate 6 and this is screwed to the base plate 15 of the stamping unit 1, said components form a functional unit. In this case, the stamping punch 5 bears in the direction of stamping in a play-free manner against the pressure plate 10 in the region of the punch shoulder 9.
Owing to the described arrangement, the stamping punch 5 can be removed or exchanged without the need for removal of the pressure plate 10 from the holding plate 6.
The stamping punch 5 is held in the holding plate 6 by doubly provided means 21 for fastening the punch head 8 to the holding plate 6. The respective means 21 has a pocket 22 made in the punch head 8, a clamping screw 24 screwed into a threaded bore 23 of the holding plate 6, a pressure piece 25 arranged in the axial direction of the clamping screw 24 between the latter and the pocket 22, and a holding screw 26 for the pressure piece 25. The holding screw 26 passes through a bore 27 of the clamping screw 24 and is screwed with a threaded portion 28 into a threaded bore 29 of the pressure piece 25. In a screwed-in position of the clamping screw 24, on a side 30 of the pocket 22 that is facing away from the punch shoulder 9, a conical portion 31 of the pressure piece 25 makes full-faced contact with a conical portion 32 of the pocket 22. In this screwed-in position of the clamping screw 24, illustrated in detail in FIG. 7, the punch shoulder 9 bears squarely against the pressure plate 10. In this case, a screw head 33 of the holding screw 26 is arranged with axial play, illustrated by the gap 34, with respect to the clamping screw 24.
In detail, that end of the pressure piece 25 that is facing away from the pocket 22 is configured as a rotationally symmetrical cylinder 35 and that end of the pressure piece 25 that is facing toward the pocket 22 is configured as a truncated cone 46. A peripheral region of the truncated cone 46 has in the region of its free end a flat contact surface 36 for the purpose of contact with the pocket 22. The pocket 22 is configured as a frustoconical recess, tapering in the direction of a floor 37 of the pocket 22 and having a flat contact surface 38, disposed at least in a peripheral region of the truncated cone, for the purpose of full-faced contact with the contact surface 36 of the pressure piece 22. In this case, the pocket 22, thus the frustoconical recess, has an oval, in particular slightly oval cross section. The extent of the pocket 22 transversely to the direction of stamping of the stamping punch 5 or in the return direction thereof is less than the extent of the pocket 22 perpendicular to this direction. This allows a certain tolerance compensation in the transverse extent, thus in the direction of the distance apart of the two pockets 22, from the aspect of production inaccuracies.
Solely for reason of simplified production, on the conical part of the pressure piece 25 there is likewise provided, also in the diametral region, a face 39.
As can be seen in particular from FIG. 7, the pressure piece 22, in the screwed-in position of the clamping screw 24, is arranged at a distance to the floor 37 of the pocket. The clamping screw 24 has a screw head 40 having an outer polygon, configured as a hexagon. In the screwed-in position of the clamping screw 24, the screw head 40 protrudes beyond the holding plate 6, so that, without the need for considerable installation space next to the stamping arrangement 2, simple actuation of the screw head 40 by means of a screwing tool is possible. The holding screw has a screw head having an inner polygon, in particular a hexagon, wherein the screw head 41 is disposed within the clamping screw 24.
FIG. 2 shows one clamping screw 24 in its screwed-in position (in accordance with FIG. 7) and the other clamping screw 24 in a partially unscrewed position (in accordance with FIG. 8).
In the stamping arrangement 2, two pockets 22 are thus made in the punch head 8, and a pressure piece cooperates with the respective pocket 22, and a clamping screw 24 and a holding screw 26 cooperate with the pressure piece 25. The pockets 22 are identically configured, just as the clamping screws 24 are identically configured, the pressure pieces 25 are identically configured, and the holding screws 26 are identically configured.
In the stamping arrangement 2 according to the invention, the stamping punch 5 is placed through the pressure plate 10 and screwed to the holding plate 6. The precise location positioning is realized by two fits in the X and Y direction. By the two means 21, the stamping punch 5 is secured against being pulled out in the Z direction. This type of securement or fastening enables rapid changing of the stamping punch 5. In the clamped state, as is illustrated in particular in FIG. 7, the respective pressure piece 25 bears against the end face of the clamping screw 24 and is pressed via its external thread into that milled recess in the punch head 8 which corresponds to the geometry of the pressure piece 25. Via the bevel on the end of the pressure piece 25, the punch shoulder 9 is drawn against the pressure plate 10 by means of the counter bevel in the punch head 8, so that the stamping punch 5 can be pressed by means of the two provided means 21, counter to the direction of stamping, with pretension against the pressure plate 10, which can then absorb the stamping pressure.
For the removal of the stamping punch 5 in the direction of stamping, the respective clamping screw 24 is loosened and, following contact of the bottom part of the screw head 41 of the holding screw 26 for the pressure piece 25 with the countersink in the clamping screw 24, the pressure piece 25 is pulled by means of the holding screw 26 out of the milled recess in the punch head 8. Upon further rotations of the clamping screw 24, the pressure piece 25 frees the stamping punch 5, specifically the punch head 8, after the pressure piece 25 is moved completely out of the punch head 8.
A further function of the clamping screws 24 is the absorption of the stripping pressure following stamping when the stamping punch 5 leaves the stamped sheet in the direction of the upper dead center. This is effected by the pressing of the respective head portion 19 against the opposite wall of the receptacle of the holding plate 6 by means of the clamping screws 24, and by the shearing resistance of the cross section of the engaged pressure pieces 25.
The forces which arise in the course of the stripping after the stamping can in this case amount to up to 100 kN.
The use of a plurality of clamping screws, in the present case the two clamping screws 24, enables narrow tolerance ranges to be managed both in the series arrangement of the clamping screw threads in respect of the holding plate 6, and of the milled recesses in the punch head 8, by which bevels in the milled recess in the punch head 8 and also on the front part of the pressure piece 25 are compensated without impairment of a clamping screw 24 in terms of its function of pressing the punch shoulder 9.
The clamping screw 24 is constituted, for instance, by a M16 screw, the holding screw 26 by a M4 screw. The pressure piece has, for instance, a diameter of 13 mm, wherein the conical portion 31 runs at an angle of 5° to the pocket axis. The oval conical pocket 22 has, for instance, dimensions of 14 mm/12 mm, with a 6 mm depth.
A second exemplary embodiment according to FIGS. 30 and 31 differs from the first embodiment only in terms of the configuration of the pressure piece 25 and means for the loose precentering of the pressure piece 25. In this respect, for the avoidance of repetitions, reference is made to the basic statements concerning the first embodiment.
In the second embodiment according to FIGS. 30 and 31, the cylindrical portion 35 of the pressure piece is provided with a groove 42 which runs in the axial direction and is open radially outward. This groove extends from that end of the pressure piece 25 that is facing away from the contact surface 36 to almost into the region of the contact surface 36. The groove 42 is arranged such that the extension of the groove 42 coincides with a line of symmetry of the contact surface 36, so that an orientation of the groove 42 corresponds to a corresponding orientation of the contact surface 36. Cooperating with the groove 42 is a setscrew 43, which in the region of its end facing toward the pressure piece 25 has a dog point 44. The diameter of the dog point 44 is slightly smaller than the width of the groove 42. The setscrew 43 is screwed into a threaded bore 45 of the holding plate 6. The setscrew 43 with dog point 44 enables a loose precentering of the pressure piece 25. It can thus easily be ensured that, when the clamping screw 24 is screwed in, the pressure piece 25, in the region of its contact surface 36, is exactly oriented with respect to the conical portion 32 in the pocket 22.
In the preassembly of the holding plate 6, the respective pressure piece 25 is oriented once with its groove 42 and the setscrew 43 is screwed in to the point where its dog point 44 engages in the groove 42 without a tensioning between the dog point 44 and the pressure piece 25. The pressure piece 25 is thus fixed with play. Neither the groove 42, nor the turned end of the setscrew 43, i.e. the dog point 44, are subjected to load, since the precentering function is fulfilled with the threading of the faces of the pressure piece 25 into the associated pocket 22 in the holding plate 6.

Claims

1. A stamping arrangement having a stamping punch and a holding plate for the stamping punch, wherein the stamping punch, in a stamping stroke, makes contact in the region of a punch shoulder with the holding plate, or with a pressure plate disposed between the stamping punch and the holding plate, and the stamping punch has a punch head and the holding plate has a receptacle for the punch head, and means for fastening the punch head to the holding plate are provided, wherein the means have:

a pocket made in the punch head,

a clamping screw screwed into a threaded bore of the holding plate,

a pressure piece arranged in the axial direction of the clamping screw between the clamping screw and the pocket, and

a holding screw for the pressure piece, wherein the holding screw passes through a bore of the clamping screw and is screwed with a threaded portion into a threaded bore of the pressure piece,

wherein, in a screwed-in position of the clamping screw, on a side of the pocket that is facing away from the punch shoulder, a conical portion of the pressure piece makes full-faced contact with a conical portion of the pocket, and, in this screwed-in position of the clamping screw the punch shoulder bears against the holding plate or the pressure plate, and a screw head of the holding screw is arranged with axial play with respect to the clamping screw.

2. The stamping arrangement as claimed in claim 1, wherein an end of the pressure piece that is facing toward the pocket is of frustoconical configuration, and a peripheral region which is present there, in the region of its free end, has a flattened contact surface for the purpose of contact with the pocket.

3. The stamping arrangement as claimed in claim 2, wherein the pocket is configured as a frustoconical recess, tapering in the direction of a floor in the pocket and having a contact surface, disposed in a peripheral region for the purpose of contact with the pressure piece.

4. The stamping arrangement as claimed in claim 3, wherein the frustoconical recess defined by the pocket has an oval cross section.

5. The stamping arrangement as claimed in claim 3, wherein the pressure piece, in the screwed-in position of the clamping screw, is arranged at a distance to the floor of the pocket.

6. The stamping arrangement as claimed in claim 1, wherein means for orienting the pressure piece in a rotational direction of the pressure piece relative to the conical portion of the pocket are provided.

7. The stamping arrangement as claimed in claim 1, wherein the clamping screw has a screw head having an outer polygon for cooperating with a screwing tool.

8. The stamping arrangement as claimed in claim 7, wherein the screw head of the clamping screw, in the screwed-in position of the clamping screw, protrudes beyond the holding plate.

9. The stamping arrangement as claimed in claim 1, wherein the screw head of the holding screw has an inner polygon, and wherein the screw head is disposed within the clamping screw.

10. The stamping arrangement as claimed in claim 1, wherein the pressure plate is connected to the holding plate and is provided with a long hole which passes through the punch head.

11. The stamping arrangement as claimed in claim 1, wherein two pockets are made in the punch head, and a corresponding pressure piece cooperates with a respective pocket, and a clamping screw and a holding screw cooperate with the corresponding pressure piece.

12. The stamping arrangement as claimed in claim 11, wherein the pockets are identical, the clamping screws are identical, the pressure pieces are identical, and the holding screws are identical.

13. The stamping arrangement as claimed in claim 1, wherein the holding plate has two receptacles and the punch head has two head portions, wherein a respective head portion is inserted into a respective receptacle and each head portion has a pocket.

14. The stamping arrangement as claimed in claim 1, wherein the punch head is guided in the holding plate in the spatial directions arranged perpendicular to the direction of insertion into the holding plate.

15. Use of the stamping arrangement as claimed in claim 1 in a stamping unit with a stripping force per stamping punch greater than about 50 kN and less than about 100 kN.