EP0125540A2 - Apparatus for making tubes with holes in the walls - Google Patents

Abstract

The invention relates to a method for making tubes formed with holes in their peripheral wall, particularly muffler tubes, in which the tubes are formed of sheet metal and subsequently welded along abutting edges of the sheet metal. Known from practical application is a method of the type defined above, in which a hole pattern is initially punched into a sheet metal strip. The metal strip is subsequently formed, as by a roll forming method, into tubes which are then closed by a longitudinal weld seam. After the welding step the tubes are cut to length by means of a cutting device, the operation of which is controlled depending on the hole pattern. It is the object of an invention to provide a method and apparatus of the type defined above which in addition to the advantage of economical production offers the possibility of forming the tubes with holes over their entire periphery. With regard to the method according to the invention, this object is attained by introducing a backing element into the previously welded tube and forcing it into engagement with the interior wall surface thereof, followed by the formation of holes from the exterior in the area of the tube supported by the backing element.

Description

The invention relates to a method for producing pipes perforated in the lateral surface.

In practice, a method of the type just mentioned is known, which is used to manufacture silencer tubes. The hole pattern desired for the later pipes is punched into a flat metal band. The strip is then shaped into tubes, for example using the roll forming method, and welded with a longitudinal seam. The pipes are cut to length after welding with the aid of a cutting device that works in relation to the hole pattern.

The known method has some disadvantages. Since a continuous strip of material is required to introduce the welding energy on both sides of the weld, the rows of holes cannot be evenly distributed around the circumference.

There are also difficulties in coordinating the various manufacturing steps. The welding process requires a minimum feed rate that is too high for punching the sheet metal strip with conventional presses and feeds. For this reason, the sheet metal strip is usually unwound from the federal government in a separate operation, punched and rewound. Since the hole patterns can differ depending on the pipe type, the pre-punching can only be carried out on a commission basis.

Appropriate search and catch devices are required to cut the pipes to length in relation to the hole pattern.

The known method is relatively complex and inflexible. Small quantities cannot be produced to cover costs.

From US-PS 1,510,718 a non-generic device for punching roller bearing cages is known. The cages each have the shape of a truncated cone. Rectangular recesses are punched into the lateral surface. The punching tool is inserted into the cage blanks from the inside and pressed outwards. The cages are held on the outside by a holding element.

The known device is only suitable for workpieces that can be machined from the side and have such an opening width that the tools for machining can be inserted from the outside into the workpiece interior, while at the same time the actuating device for the workpieces remains essentially outside. The angular inclination of the outer surface of the workpieces to the body axis makes this machining even easier, since the tools can then get into the interior of the workpieces through the respective further body opening. Pipes with an essentially constant and relatively narrow cross-section cannot be perforated on the known device, since the tools can at most operate in the area of the pipe openings, but not in the axial central area of the pipes.

The invention has for its object to provide a method and an apparatus of the type mentioned which, in addition to the advantage of economical production, offer the possibility of perforating pipes in their outer surface over their entire axial extent and over their entire circumference.

This object is achieved in that a support element is inserted into the tube and pressed from the inside against the tube and subsequently the tube area acted upon by the support element is perforated from the outside.

The method according to the invention is simple and offers various advantages. It is equally suitable for seamless pipes and those with seams. The latter are formed and welded before punching. Regardless of the hole design, shaping and welding can be optimized in the respective workflow. The tubes can be made in stock for common diameters. For the special design of the pipes, it is then sufficient to determine the pipe length and to determine the hole pattern.

With the method according to the invention, the manufacturer gains great freedom of disposition and is flexible in the recycling of the prefabricated pipes. The process can be used economically for both large and small quantities. This is a decisive factor in cost accounting. Reorders for smaller quantities can be processed just as economically as bulk orders, since pre-made pipe blanks can also be used for reorders, which are only provided with the desired hole pattern after knowledge of the order.

When punching, the invention provides the decisive advantage that the tube can be perforated over its entire circumference. As a result, the hole pattern can extend over the weld seam without interruption. The welded connection no longer needs to be taken into account. Fully axisymmetric hole patterns can be created. Perforated pipes of the type mentioned are usually also used as silencer pipes. The damping properties are increased by the symmetrical hole design.

With the invention it is also possible to punch seamless tubes without difficulty. There is no need to fear that the tubes will lose their cross-sectional shape during perforation. The hole pattern can be set as desired. The weight-free seamless aluminum tubes can be used especially for silencer tubes.

The invention provides a device for producing perforated, axially symmetrical workpieces in the lateral surface with a punching tool and a holding element arranged on the outside of the workpiece.

The support element on the inside of the pipe serves to support the pipe to be punched during the punching process. It holds the pipe tight and tensions it. It also secures the pipe against unwanted evasive movements during processing. The pressure mandrel presses the support elements outwards during processing and in turn holds the support element in the working position.

The invention is suitable for pipes with and without seam and with any possible cross-sectional shape. However, it will primarily be used for pipes with a circular cross-section.

Regardless of the pipe cross-section, it is possible according to an advantageous development of the invention that two support elements are arranged diametrically opposite one another with respect to the pipe cross-section of the workpieces and that a common contact mandrel is assigned to them.

The paired arrangement of the support elements and the associated punching tools offers the advantage that the punching forces act against one another, so that the support elements and the mandrel and any other parts which are still acted upon by the forces during machining are not loaded on one side.

With regard to the punching process, it is advantageous if the support element is designed as a die containing a hole pattern. The hole pattern can either have a predetermined hole pattern depending on the workpiece or be in the form of a surface pattern that contains all possible hole positions. The design of the support element as a perforated die facilitates the punching process. The punch waste can be pushed through the die.

Among other things, with regard to the automatic removal of the punching waste, it is advantageous if the punching tool and the support elements and the mandrel are aligned vertically. The punching waste falls after the punching due to its own weight and can be collected centrally there. Failure of the waste can also be accelerated by pressurizing the mandrel bore with compressed air. A simple tensioning of the support element is achieved in that each support element has a sawtooth-like inner surface, which is assigned a sawtooth-like, outwardly directed counter surface on the pressing mandrel. If you move the pressure mandrel relative to the support element, the opposing saw teeth of the support element and the pressure mandrel run against each other. Due to the wedge effect, each support element is pressed radially outward against the pipe to be machined during an axial movement of the mandrel. The loosening takes place in the other order, in that the saw teeth slide off one another and the support element can thereby move away from the workpiece.

Each support element is advantageously arranged in the interior of a guide half-shell open towards the workpiece, which is formed by the holding element. The guide shell complements the support element. The workpiece is located between these two parts. It is held in between. The guide half-shells can be designed so that they are suitable for holding pipes of different cross-sectional shape and diameter.

The holding element supports the workpiece at least in the machining area, that is to say in the present case primarily along a pipe surface line. The flat design of the holding element is sufficient for this. However, its shape can also be adapted to the workpiece in such a way that it rests on the workpiece outside of the machining area. A simple mounting of the support elements results from the fact that they are held at the upper end of the respective guide half-shell. In this way, the workpieces can be inserted from below between the support elements and the guide half-shells.

In order to be able to position the stamps of the punching tool securely, it is favorable if the guide half-shells are provided with guide bores for receiving the stamps. Since the guide half-shells are arranged directly next to the workpiece during machining, they are able to hold and guide the punches of the punching tool exactly.

A simple shape of the punching tool results when the punches are arranged one above the other, primarily along a surface line of the guide half-shells. As a result, the punches can also attack the workpieces along a surface line. This means that it is sufficient to clamp the workpiece between the support element and the guide half-shells along said surface line.

In order to enable a uniform work attack of the punching tool, it is favorable if the stamps are assigned a common actuating element.

For the optional use of the punches, an activation bar can be provided in the actuating element, which only connects those punches with the actuating element that are actually to be used for processing the workpiece in question. Other stamps, which are present in the punching tool, but which are not used in the workpiece to be machined, are not linked to the actuating element by the activation bars and therefore do not take part in the machining. They remain on standby.

In order to avoid an uneven work attack, it is advantageous if the actuating elements of two or more punching tools have a common feed drive exhibit. A simple solution for this is that the feed drive comprises two sliding wedges flanking the punching tools, to which counter-wedges are assigned on the drive side. The counter wedges advantageously have a common yoke acted upon by an actuator. The actuator can effect the feed centrally. An uneven movement of the punching tools is avoided. At the same time, it is possible to provide a stroke setting element between the yoke and the actuator, with which the stroke can be changed depending on the workpieces to be machined.

In order to limit the stroke, spacer blocks can be provided between the guide half-shells assigned to one another. The spacer blocks are used for the unchangeable mutual positioning of the guide half-shells. They define the free space between the guide half-shells arranged opposite one another. It can be easily adapted to different workpieces by selecting the spacer blocks. The aim of the coordination can be that when the guide half-shells are placed on the spacer blocks, the workpieces between the guide half-shells are kept free of deformation but also free of play. The spacer blocks are centered by turning them on guide columns, so that the guide half-shells also assume an exactly central position during the punching process. This avoids off-center loads on the mandrel.

For the workpiece feed, it is advantageous if a lifting table is present which has workpiece receptacles which can be rotated about a vertical axis. The lifting table enables the workpieces to be inserted from below between the support elements and the guide half-shells. In the ready position, it can easily be fitted with new prefabricated pipe sections. Automatic assembly is also possible. For the actual editing the lifting table is raised together with the workpieces, it advantageously being possible to raise the workpieces for processing to different extents in order to offset the height of the holes of one surface line relative to the holes of adjacent surface lines. The rotary mounting of the receptacles enables the workpieces to be rotated individually or together step by step after punching a vertical row of holes in order to punch further rows of holes.

For the mutual alignment of the receptacles with the mandrel, it is provided that the receptacles have a centering opening for the mandrel. The centering takes place when the lifting table is raised.

An exemplary embodiment of the invention is described below with reference to a drawing.

• Figur 1 eine Seitenansicht einer erfindungsgemäßen Vorrichtung,
• Figur 2 eine Vorderansicht der Vorrichtung von Fig. 1,
• Figur 3 eine Teildraufsicht auf die Stanzwerkzeuge der Vorrichtung von Fig. 1, gemäß der Linie III-III von Fig. 4,
• Figur 4 einen Schnitt durch die in Fig. 3 gezeigten Teile gemäß der Linie IV-IV und
• Figur 5 eine Teilansicht des Stellantriebes für die Werkzeugaufnahmen.

Show it:

• FIG. 1 shows a side view of a device according to the invention,
• FIG. 2 shows a front view of the device from FIG. 1,
• FIG. 3 shows a partial top view of the punching tools of the device from FIG. 1, along the line III-III from FIG. 4,
• Figure 4 shows a section through the parts shown in Fig. 3 along the line IV-IV and
• Figure 5 is a partial view of the actuator for the tool holders.

The device 1 according to the invention is used to manufacture pipes perforated in the lateral surface, in particular silencer pipes. The tubes are formed outside of the device from sheet metal and then ent welded along a connecting edge. The invention can also accommodate seamless tubes. In any case, the tubes for processing in the device according to the invention have already been cut to length.

As is shown in particular in the side view of FIG. 1, the device has an L-shaped frame 2. The device shown is designed as a multiple punching device for pipes. In the upper half of the free space of the L-shape there are three pairs of punching tools 3 next to one another, which can be actuated by a common drive 4 in a manner to be explained later. The punching tools are held in a holder 5 which is arranged at the upper end of the vertical leg of the frame. It spans the free space of the L-shape and protrudes slightly towards the front of the horizontal L-leg.

A lifting table 6 is arranged below the holder 5 and has three receptacles 7 for workpieces 8 arranged in a line one behind the other.

In the case shown, the workpieces consist of three sections of a cylinder tube of equal length. They are kept strictly vertical in the recordings 7. The details of the lifting table and the recordings will be discussed later.

The lifting table can be moved up and down along two vertical guides 9, which extend parallel to the L-leg of the frame and are arranged on the frame at a constant mutual distance from one another.

So much for the overview of the device. The punching tools and the parts around them will first be explained below.

The punching tools 3 are arranged in pairs in the device. This can be seen particularly clearly from FIG. 3. Three processing stations 10, 11, 12 can be seen, each of which is equipped with two punching tools 3 lying opposite one another.

Each processing station is able to provide a workpiece, in the present case a cylindrical tube section 8 with a predetermined hole pattern, the hole patterns of the different workpieces not having to be identical to one another.

In the core of each processing station, a mandrel 13 is arranged, which protrudes upwards from each station and is supported there by means of adjusting devices 14 so that it can be raised and lowered on a cross member of the holder 5. In the present case, the mandrel has a circular cross section. Along the mandrel axis there is a central bore 15 which runs over the entire height of the mandrel and through which the punching waste falls downward, as will be explained below.

On its outside, the vertically aligned mandrel 13 has a sawtooth profile that has teeth that taper slightly downward. In the area of the teeth, the mandrel is provided with a slot 17 on the circumferential parts opposite the punching tools 3, in order to allow punches 16 of these tools or punching waste to penetrate the mandrel.

The mandrel forms a central actuating element for two supporting elements 18 arranged next to it, which flank it on opposite sides. The support elements are designed as vertical strips and have an approximately rectangular cross section. One side of the rectangle is designed as a semicircle and adapted to the inner wall of the workpiece to be machined.

The support elements 18 can be embedded in vertical grooves of the mandrel. On their side of the rectangle facing the center of the mandrel, they have a sawtooth-like inner surface which corresponds to the sawtooth-like outer surface of the mandrel in such a way that the saw teeth of these two parts hook into one another. This means that the saw teeth of the support elements taper slightly upwards.

The support elements 18 serve as counterholders for the punching tools 3. If the mandrel is moved vertically downward, the saw teeth of the mandrel run against those of the support elements and press the support elements radially outward into contact with the pipe workpieces. In the device shown, the contact is made at least along the surface lines of the tube workpieces, into which holes are to be punched in accordance with a predetermined pattern.

The support elements 18 are diametrically opposite with respect to the tube cross section of the workpieces. They are each designed as a matrix containing a hole pattern. The grid of holes contains a series of bores located one above the other, which are arranged at a predetermined distance from one another.

While the support elements are used to support the inside of the pipe, the outside are used for fixing Workpieces each have a pair of guide half-shells 19 which have a U-shaped cross section, the opening of which is directed towards the workpiece. The U-shape is matched to the diameter and cross-sectional shape of the largest workpiece. It encompasses such a workpiece. In the case of a tube, however, the guide half-shells 19 can only rest on the workpieces along the surface line which is also provided with the row of holes. The guide half-shells have horizontal guide bores for receiving the punches 16 of the punching tools 3. Analogous to the hole pattern of the support elements, the guide bores are arranged vertically one above the other along a line and have the same mutual spacing as is present in the row of holes of the support elements.

The support elements 18 each have at their upper ends radially outwardly extending hooks 20 with which they are suspended in corresponding recesses in the guide half-shells. In this way, the support elements are mounted on the guide half-shells in a radially variable manner. This is necessary because there must be sufficient space between the support elements and the guide half-shells for moving the workpieces in and out.

The punches 19 of the punching tools 3 are arranged vertically one above the other, analogous to the bores of the support elements and the guide half-shells. They are aligned horizontally. The stamps of each punch 3 extend radially outward from the corresponding guide half-shell to a common actuating element 21 which is formed as a vertical pressure bar. The actuating element contains a selective one set of stamps each have a vertical activation bar 22 which connects predetermined stamps to the actuating element in a tensile and compressive manner. The activation bars can be inserted from above into a groove in the actuating element and contain stamps that are not used for special processing

so that they are not subjected to a horizontal displacement of the actuating element.

It can be seen from FIG. 3 that behind the actuating elements 21 arranged on each side of the axis of symmetry S of the machine frame there is a pressure plate 23 which extends over the entire height of the punching tools and in the horizontal direction over the ends of the three processing stations 10, 11, 12 protrudes. In the present case, the pressure plate 23 therefore spans three punching tools 3 of the processing stations 10, 11, 12 located next to one another. This is done deliberately because one wants to achieve a uniform loading of the punching tools during feed.

In view of this goal, not only are the punching tools on each side combined in terms of drive by a common pressure plate, but there is also a central drive 24 which is able to apply all the punching tools evenly via intermediate members. A sliding wedge 25, which has a vertical wedge surface that is inclined so that the wedge tapers in the direction of the drive 24, is fastened to the outside of each pressure plate as the first intermediate member. Opposite wedges are assigned to the sliding wedges as a second intermediate link, the inclined surface of which is in contact with the inclined surface

Wedge surface of the sliding wedge.

The counter wedges 26 are thus supported with the inclined surface on the sliding wedges, while they are in contact with the mounting plates 5 with the flat wedge surface. The counter wedges are fastened at their thickened end to a common yoke 27 which is connected to the central drive 24 in a pull-resistant and thrust-resistant manner via a stroke adjustment element 27. The stroke setting element is designed, for example, as a screw connection between the yoke and the punch of the feed drive and is used primarily to shift the stroke as a function of the workpieces to be machined.

It can be seen from FIGS. 3 and 4 that the mounting plates 5 are connected to one another via, in the present case a total of eight, tie rods 29. Four tie rods are located in a lower plane E1, which, as shown in FIG. 4, extends horizontally in the region of the lower ends of the punching tools 3. Four further tie rods are located in a plane E2, which is arranged analogously in the area of the upper end of the punching tools 3. The sliding wedges 25 and the counter wedges 26 are arranged between the planes E1 and E2.

The tie rods are columnar. The mounting plates 5 are anchored to pull and slide. The columns serve for the storage of several parts, for example the pressure plates 23, which are displaceably supported by means of bushes 30 on the outermost columns of the upper and lower levels E1 and E2.

However, spacer blocks 31 are also held on the columns symmetrically to the plane of symmetry S, which in the present case are designed in the form of strips and on twists in the tie rods 29 (see partial section in FIG. 3 above) are fixed immovably in said plane of symmetry. The spacer blocks serve as stroke limiters for the guide half-shells 19. The half-shells are connected to the actuating elements 21 via horizontal support rods 32. But the connection is not rigid. The actuating elements can be moved for the actual punching stroke in the direction of the guide half-shells against the force of springs 33 which are clamped between the guide half-shells 19 on the one hand and the actuating elements 21 on the other hand.

The spacer blocks 31 project into the stroke area of the guide half-shell 19 and determine the position of the guide half-shells closest to the workpiece as a function of the workpiece during machining. In this way, deformation of the workpieces during punching is to be avoided.

The guide half-shells 19, the actuating elements 21 and the sliding wedges 25 are thus held in the horizontal direction on the tie rods 29 via the pressure plates 23.

Now to the lifting table 6. In FIGS. 1 and 2, it is shown in its lower ready position, in which the workpieces can be inserted into the receptacles 7 and removed from them again.

In Figure 4 of the drawing, however, the lifting table 6 is in the processing position. It has moved all the way to the lower end of the punching tools and has inserted the tubular workpiece 8 so far between the support elements 20 and the guide half-shells 19 that the workpiece can be provided with the desired holes over its entire length. To the mandrel 13 with his To anchor the lower end securely in motion, the receptacles 7 each have a centering opening 34, into which the mandrel projects when the lifting table is in the processing position. It is held there against lateral displacement.

The receptacles have an opening which is coaxial with the through hole 15 and through which the punching waste falls downward.

FIG. 5 schematically shows the rotary drive for the receptacles 7 of the lifting table 6. The three receptacles are each rotatably mounted about vertical axes and are connected to one another in motion by means of meshing gears 35, 36 and 37. The middle receptacle is connected via a reduction gear 38 to a stepper motor, which is used to gradually turn the workpieces for punching. Since only the bores of a surface line of the workpiece are punched out in each machining operation, the stepwise rotation of the receptacles can result in the entire surface of the workpiece being machined.

In the drive shown for the receptacles, adjacent tubes are driven in opposite directions. If this is not desired, it is also possible to provide a drive in the same direction for all pipes. Likewise, it is conceivable to create a continuously controllable, step-independent drive instead of a stepper motor.

In the method according to the invention, a sheet metal strip or a sheet metal of some kind is first used Cutting pipes shaped and then welded together at the pipe seam. They can then be cut to length. For punching the holes, a support element is inserted into the already welded pipe and pressed against the pipe. The punching takes place from the outside, the support element serving as a counter-holder for securing the workpiece and for absorbing the punching forces. In order to easily remove the punching waste by falling down, the tube is held vertically during the punching. If a force balance is desired, it is possible to punch the tube simultaneously from two opposite directions.

During operation of the device according to the invention, the workpieces, for example the prefabricated pipes, regardless of whether with a seam or seamlessly, are inserted from above into the receptacles 7 of the lifting table 6 and clamped vertically there. The lifting table is in the lower standby position shown in FIGS. 1 and 2. After clamping, the lifting table is moved vertically upwards, whereupon the workpieces are moved into the space between the support elements 20 and 19 as far up as is necessary for the desired machining. When the lifting table is raised, the mandrel 13 is centered in a centering opening in the receptacles 7. The mandrel 13 is displaced downwards for tensioning the support elements 20 with the aid of the actuators 14, whereupon the support elements are pressed radially outward into contact with the workpieces due to the run-up of the saw teeth.

If the central feed drive 24 for the punching tools is now set in motion, the drive presses the yoke 27 in the direction of the punching tools 3. Die Ge Counter wedges 30 run on the sliding wedges 25 and thus move the pressure plates 23 in the direction of the workpieces.

The actuating elements 21 are advanced in the direction of the workpieces 8. The guide half-shells 19 move in the direction of the pipe to be punched and clamp it firmly on the support elements 20. At the same time, they come into contact with the spacer blocks 31, which serve as stroke limiters for the guide half-shells. The distance between the actuating elements 21 and the guide half-shells 29 is reduced. The springs in between are compressed. They are prestressed so far that they can absorb any unevenly occurring side forces and relieve the mandrel.

The punches provided for machining the workpiece are connected to the respective actuating element 21 in a tensile and shear-proof manner via the activation bar 22. Only they are pushed forward towards the workpiece and punch the desired holes out of the workpiece. The stroke of the punching tools is dimensioned such that the punches penetrate into the mandrel and deliver the punching waste to the vertical through hole 15. The waste falls down through the receptacle 7 into the open.

Due to the first stroke, holes were punched along two diametrically opposed surface lines. To punch additional holes along other surface lines, it is necessary to pull the punching tools back so far that they are again outside the workpiece. Subsequently, with the help of a central pick-up drive, each workpiece can be moved a certain step be rotated further, whereupon the previously described punching process takes place again.

For the return stroke of the punching tool, regardless of whether between the processing steps or at the end of processing, the punch of the central feed drive 24 moves back together with the yoke 27 and the counter wedges 30. As a result, the springs 33, supported on the guide half-shells fixed by the spacer blocks 31, are able to push back the actuating elements 21 and partially withdraw the punches from the workpieces, while the return stroke is generally carried out by the wedge drive.

After the processing has ended, the lifting table moves downward from the processing position shown in FIG. It releases the mandrel 13 at the same time. The recordings detach from the workpieces, whereupon these can be removed.

The device according to the invention offers the manufacturer and customer the possibility of a short disposition. A quick tool change is possible even with different hole diameters. Different hole patterns can be achieved at any time by exchanging the activation bars 22. The device is relatively small and requires relatively little investment, which means that even small quantities can be produced economically.

A decisive advantage of the invention is that the workpieces can be provided with holes over their entire circumference. Both longitudinally welded and seamless drawn tubes can be processed in various materials, especially aluminum.

Claims (25)

A process for the production of pipes loved in the lateral surface, characterized in that a support element is inserted into the tube and pressed against the pipe from the inside, and subsequently the pipe area acted upon by the support element is perforated from the outside. 2. The method according to claim 1, characterized. that the tube is held vertically when punching. 3. The method according to claim 1 or 2, characterized in that the tube is simultaneously perforated along two diametrically opposed surface lines. 4. Device for producing perforated axially symmetrical workpieces in the lateral surface with a punching tool and a holder element arranged on the outside of the workpiece, characterized in that the punching tool (3) is assigned at least one support element (18) which is adapted to the inner shape of the tube with a pressing mandrel (13) and that the punching tool is passed through the holder element (19). 5. The device according to claim 4, characterized in that two support elements (18) are arranged diametrically opposite one another with respect to the tube cross section of the workpieces and a common pressure mandrel (13) is assigned to them. 6. The device according to claim 4 or 5, characterized in that the supporting element (18) is designed as a matrix containing a hole pattern. 7. The device according to at least one of claims 4 to 6, characterized in that the punching tool (3), the support elements (18) and the mandrel (13) are aligned vertically. 8. The device according to at least one of claims 4 to 7, characterized in that the supporting element (18) has a sawtooth-like inner surface, which is assigned a sawtooth-like, outward-facing counter surface on the pressing mandrel (13). 9. The device according to at least one of claims 4 to 8, characterized in that the pressing mandrel (13) is held displaceably in the mandrel direction at the upper end of the device. 10. The device according to at least one of claims 4 to 9, characterized in that each support element (18) is arranged inside a guide half-shell (19) open to the workpiece, which is formed by the holding element. 11. The device according to at least one of claims 4 to 10, characterized in that the support elements (18) are held at the upper end of the respective guide half-shell (19). 12. The device according to at least one of claims 4 to 11, characterized in that the guide half-shell (19) is provided with guide bores for receiving stamps (16) of the punching tool (3). 13- Device according to at least one of claims to 12, characterized in that the guide bores correspond in terms of location and number at least to the bores of the die (18). 14- Device according to at least one of claims 4 to 13, characterized in that the punches (16) of the punching tool (3) are arranged one above the other primarily along a surface line of the guide half-shell. 15- Device according to at least one of claims 4 to 14, characterized in that the stamps (16) of each punching tool (3) is assigned a common actuating element (21). 16. The device according to at least one of claims 4 to 15, characterized in that the actuating element (21) workpiece-dependent activation strips (22) for the optional use of the stamp (16). 17. The device according to at least one of claims 4 to 16, characterized in that the actuating elements (21) of two or more punching tools (3) have a common feed drive (24). 18. The device according to at least one of claims 4 to 17, characterized in that the feed drive (24) comprises two sliding wedges (25) flanking the punching tools, to which drive wedges (26) are assigned on the drive side. 19. The device according to at least one of claims 4 to 18, characterized in that the counter wedges (26) have a common yoke (27) acted upon by an actuator. 20. The device according to at least one of claims 4 to 19, characterized in that a stroke adjusting element (28) is present between the yoke (27) and feed drive (24). 21. The device according to at least one of claims 4 to 20, characterized in that spacing blocks (31) are present as stroke limiters between guide half-shells (19) arranged opposite one another. 22. The device according to at least one of claims 4 to 21, characterized in that at least the guide half-shells (19), the punching tools (3), the actuating elements (21) and the sliding wedges (25) are slidably mounted on horizontal guides (29). 23. The device according to at least one of claims 4 to 22, characterized in that a lifting table (6) is provided for the workpieces, each having workpiece receptacles (7) rotatable about a vertical axis. 24. The device according to claim 23, characterized in that the receptacles (7) have a centering opening for the mandrel (13). 25. The apparatus of claim 23 or 24, characterized in that the receptacles (7) is associated with an actuator for gradually rotating the workpieces (8) for punching over at least part of the lateral surface thereof.

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