EP1554109B1 - Device for punching, stamping and/or shaping flat elements - Google Patents

Abstract

A device for punching, stamping and/or shaping flat elements ( 29 ) includes a base body ( 1 ) with a table ( 18 ) and support ( 26 ) for the flat element ( 29 ), and a base plate ( 17 ), which supports a punch ( 24 ), and which is advanced with a drive ( 4,5 ) toward the support ( 26 ) and into a working station (II), bringing the punch ( 24 ) into contact with the support ( 26 ). A large number of successive, very short, highly precise, punching strokes make punched holes or stampings. Short stop periods and short clock times are used for fast moving flat elements ( 29 ). Transfer apparatus ( 9, 7; 35; 43; 46 ) coupled between the drive ( 4,5 ) and the base plate ( 17 ) move the base plate ( 17 ) without building up pressure from a position of rest (I) The punch ( 24 ) is not in contact with the support ( 26 ), up to immediately in front of working position (II). The base plate ( 17 ) is then moved into working position (II) while producing a high pressure between the base plate ( 17 ) and the flat element ( 29 ). During further operation of the drive ( 4,5 ), the base plate ( 17 ) is returned to the position of rest (I,II) without building up pressure.

Description

The invention relates to a device for punching, embossing and / or forming flat elements with a base body with table and support for the flat element and with a tool base bearing a base plate, which by means of a drive for performing the processing operation on the support out in a processing station for the engagement of the tool punch with the support and away from the support is movable away.

Such devices are used to punch or deform flat semi-finished products, such as plates, strips and blanks in a continuous process. These webs, bands, plates or blanks, which are referred to as flat elements, can be made of different materials, for example cardboard, laminated board material, multilayer material, sheet metal.

Previously known devices similar to the type mentioned above are provided with a direct hydraulic or pneumatic drive with a cylinder acting on a punching tool.
The full punching force must be applied in the punching direction, resulting in a jerky or jerky force curve and only low clock speeds can be achieved because the withdrawal of the cylinder acts as Vertustzeit.

Other known solutions work with pneumatic cylinder as a drive and integrated linear guide, which results in addition to the described detours in mass production, the further disadvantage of a lower life. In practice, some malfunctions were detected after 40 hours. For these reasons, previously used punching tools are considered as brakes of the machines.

There are also known devices with a rotary punching tool whose axis is parallel to the strip to be processed, while transverse to the direction. Even with these known devices can punch without stopping the tape. During the punching process, however, the rotational speed of the punching tool and the speed of the strip to be processed must be absolutely synchronized. Such solutions have hitherto been known only in embodiments in which the precision of the punching required for many applications is not achieved. There are both problems to comply with the exact position coordinates of a hole and the diameter or profile tolerances and the tolerances for right-angled cut from top to bottom, so the hole wall to comply.

DE-U-1 974 429 discloses a device according to the preamble of patent claim 1.

The object of the invention is therefore to provide a device of the type mentioned above, with a large number of very short, high-precision punching strokes in succession for the introduction of punched holes or embossments are possible. In particular, with fast moving flat elements while short downtime and thus short cycle times, even possible small processing strokes to be achieved.

The solution of this object is achieved according to the invention characterized in that between the drive and the base plate at least one pivotable about a fixed pivot pivot lever is coupled, which is the base plate from a rest position in which the tool post of the support is out of engagement, substantially without pressure build-up just before the machining position, then moved to a short distance to produce a high pressure between the base plate and flat element in the processing position and the base plate back to rest in further activity of the drive over areas substantially no pressure build-up that the long rotary lever to one on the body fixed pivot point and pivotally coupled at one end via a toggle joint with one end of a short pivot lever, the other end is coupled via a toggle lever bearing with the base plate, and at the other end of the rotary lever of the drive so gebra Cht is that the drive is axially outward of the fulcrum, and that the rotary lever is much longer than the short pivot lever .. With the device according to the invention can be in flat semi-finished punching holes and / or embossing introduce. The flat semi-finished products are generally referred to herein as flat elements.

With the new device can punch in particular in a continuous process holes in an economical manner in these flat materials and to the highest precision or take similar economic and precise impressions in such materials. In contrast to the prior art, very short downtime, a short machining operation with a small stroke are performed according to the invention, so that one speaks of very short cycle times.

The invention is based on the basic idea to drive the attached to the base plate tool punch according to a certain movement pattern. It is about the movement ultimately of the tool punch on the support or away from this, which holds the flat element. In the case of punching, a hole may be provided in the post so that the tool post pierces through the flat element into that hole of the post. When embossing analogous considerations apply. According to the invention, the movement pattern itself should follow the principle of moving the tool punch (and thus the base plate) toward and away from the processing position without significant pressure build-up, in which case a greater movement speed is provided. On the other hand, if the tool punch arrives in the machining position, then the movement should take place only for a short distance, but to generate a high pressure. This movement pattern is achieved via an intermediate rotary lever between the drive and the base plate. The tool stamp will be beneficial over the whole Depth of cut or embossing depth away during this processing always kept absolutely parallel to the plane of the flat element. Such a construction is robust and precise.

In accordance with the invention, this advantageously achieves a flat, gentle, sliding and non-jerky course of force. By the invention, those shocks that occur in conventional devices when the full punching force is applied in a linear direction can be avoided.

In one embodiment, the invention provides that the axis of the drive is perpendicular to the axis of the tool punch. You can think of different constructions. For example, the drive can be a pressure transducer with a cylinder and a piston whose piston movement in one embodiment runs parallel to the conveying direction of the flat element. Since the axis of the tool punch is arranged perpendicular to the plane of the flat element, then the drive axis is perpendicular to the axis of the tool punch. Among the numerous other embodiments, such is conceivable in which the drive is a motor whose axis of rotation is parallel to that of the tool punch; in a particular embodiment, the axes even collapse. When using the basic idea according to the invention, the person skilled in the art will select the suitable construction depending on the advantages that this offers for him.

Another preferred embodiment, in which the axis of the drive is perpendicular to the axis of the tool punch, is characterized in that the linear direction of movement of the base plate is determined by acting between the base body and the base plate column guide and that the drive in its lying perpendicular to it Has axis (of the drive) linearly oscillating drive means. Such an oscillating drive means may be, for example, a reciprocating piston type pneumatic or hydraulic cylinder. The piston rod can be considered as such a linear, oscillating drive means by which one can think of the axis of the drive. Perpendicular to then again runs the axis of the tool punch. The column guide allows precise angular posture and precise machining, for example punching or stamping.

As mentioned above, it is advantageous if the long rotary lever is pivotable about a fixed to the base pivot point and coupled at one end via a toggle joint with one end of a short pivot lever, the other end is coupled via a toggle lever bearing with the base plate. This mechanical structure provides a dead center in a certain position of the long rotary lever and the short pivot lever, and this results in consideration of the above basic idea greatest force effects in the vicinity of this dead center. Among other things, this is achieved by the long path of the linearly oscillating drive means with the advantage of a short path of the machining tool, for example tool punch. there the drive may comprise a pneumatic cylinder or a hydraulic cylinder. The long rotary lever, coupled with the short pivot lever (toggle principle) can be regarded as a kinematic system, which acts so that the base plate both in the direction of rotation of the long rotary lever counterclockwise and in the clockwise direction of rotation one machining operation, for example a Punching process is performed. Here, the principle according to the invention can be realized clearly, namely that first with large and fast stroke and low force of the tool punch brought close to the flat element and then made with a short path and great power processing; which in turn, with a large and fast stroke and low force, the tool punch is removed from the flat element or moved away.

It is also possible to imagine the flat element as a moving material strip, wherein processing of this strip in a continuous process can be carried out in an economical and very precise manner. This is achieved with the measures according to the invention by the very short downtime and the equally short machining operation with a small stroke. The new device allows extremely short cycle times and the processing of ribbons or webs as flat semi-finished products when passing through. This also applies to very fast moving belts and trains.

With the device according to the invention, longer service lives are achieved for these fast moving webs because only a single forward or backward stroke of the base plate is required per processing. You also get higher clock speeds, especially because, for example, in the long rotary lever and the short pivot lever with the drive whose axis is perpendicular to the tool punch, both the forward stroke and the return stroke are used for each machining operation. In one embodiment with a servomotor as a drive to achieve the advantageous high clock speed, because in each case one revolution of the servo motor can be converted into one, preferably even more punching.

With all the above-mentioned advantages, surprisingly, high precision is achieved with regard to the accuracy of the positional coordinates, the hole profile tolerances and the hole wall tolerances in the case of punching (and analogous to embossing or deformation).

Figur 1

den langen Drehhebel und kurzen Schwenkhebel, die über ein Kniehebelgelenk miteinander verbunden sind, in einer ersten oder Ruheposition (Ausgangsposition),

Figur 2

die gleiche Ausführungsform wie in Figur 1, jedoch bei dargestellter tiefster Position des Werkzeugstempels (Bearbeitungsposition) und

Figur 3

die gleiche Ausführungsform wie bei den Figuren 1 oder 2, jedoch in der ausgefahrenen Position des Antriebes, bei welcher der Werkzeugstempel mit Basisplatte wieder in seine Ruheposition zurückgefahren wurde, jedoch bei umgekehrtem Schwenkwinkel des Drehhebels im Vergleich zu Figur 1.

Further advantages, features and applications of the present invention will become apparent from the following description of preferred embodiments in conjunction with the accompanying drawings. In these show:

FIG. 1

the long rotary lever and short pivot levers, which are connected to each other via a toggle joint, in a first or rest position (starting position),

FIG. 2

the same embodiment as in Figure 1, but at the illustrated lowest position of the tool punch (machining position) and

FIG. 3

the same embodiment as in Figures 1 or 2, but in the extended position of the drive, in which the tool punch with base plate was moved back to its rest position, but at the opposite pivot angle of the rotary lever in comparison to Figure 1.

The illustrated in the drawings embodiment of the device according to the invention is shown and explained for better understanding based on the punching as processing. Here, as a flat element on a support straight translationally guided band of metal is selected and described. A limitation of the invention to this type of flat element to be processed is not pronounced thereby.

The one device for punching a horizontally continuous metal strip is shown in FIGS. 1 to 3. On a base body 1 of the punching device, a holder 2 for a cylinder pivot bearing 3 is attached. A pneumatic cylinder 4, which is selected here as a drive, is mounted on the main body 1 via the cylinder pivot bearing. In the pneumatic cylinder 4, a piston rod 5 is mounted linearly movable so that at the free end of the piston rod 5, a clevis 6 is mounted, depending on the control of the pneumatic cylinder 4 in the outward direction 7 (arrow) or the inward direction 8 (arrow ) is movable. A long rotary lever 9 is pivotally connected to the upper bearing 10 of the rotary lever 9. The long rotary lever 9 can be pivoted about its fixed to the base 1 pivot point 11 by means of the drive 4, 5. For this pivoting is located in the base body 1, a recess 12th

At its opposite the upper bearing 10 end of the long rotary lever 9, this has a toggle joint 13, to which a short pivot lever 14 is articulated. The latter is rotatably connected via its lower, provided at the other end of the pivot lever 14 toggle bearing 15 with a holder 16 which is fixedly attached to a base plate 17.

The main plane of this base plate 17 is horizontal, so is at a distance and parallel to a table 18 which is also attached to the base body 1. While the latter is stationary, the base plate 17 can be moved translationally upwards in the upward direction 19 and the downward direction 20. This movement is performed by the drive with the pneumatic cylinder 4 and the piston rod 5. So that the base plate 17 remains parallel to the horizontal plane of the table, a column guide 21 is provided, the structure of the figures 1 to 3 is clearly visible and need not be described further here, because a column guide is known per se and not the subject of this invention , While the holder 16 is mounted on the upper side of the base plate 17, is located on the opposite lower side of a holding part 22 for a resiliently biased by a compression spring 23 tool punch 24. The tool punch 24 is thus in the upward direction 19 and downward direction 20th relative to the base plate 17 movable. The longitudinal center axis of the tool punch 24 lies in the same direction and is designated as the axis 25 of the tool punch 24. In this axis are also in this embodiment, the toggle lever bearing 15 and the pivot point 11. This results in the possibility of a toggle lever dynamics, as will be described with reference to Figures 2 and 3.

On the table 18, a plate-like support 26 is fixed, in the middle of a hole 27 is mounted with ground upper edges 28, whose dimension is matched with precision to the outer edge of the tool punch 24 in a conventional manner. Only schematically, the metal strip 29 is indicated on the support 26, which lies between the support 26 and the tool punch 24.

In Figure 1, the rest position I of the base plate 17 is shown, in which the tool punch 24 is at a sufficient distance above the metal strip 29, without being engaged with the latter. When the drive moves the piston rod 5 in the outward direction 7, the long rotary lever 9 is moved from the position shown in FIG. 1 to the machining position shown in FIG. By the toggle lever dynamics initially results in a longitudinal movement of the holder 16 with the base plate 17 in the downward direction 20 (punching direction) quickly and without pressure build-up. As soon as the tool punch 24 comes into contact with the metal strip 29, the toggle joint 13 is in the dead center region. The movement of the long rotary lever 9 causes in other words shortly before the processing position II, in the same and shortly after this only a small stroke with very large force. The machining is in the case of the embodiment of Figure 2 is a punching, and here the punched hole disc 30 is shown schematically. If the piston rod 5 is further moved in the outward direction 7, the long rotary lever 9 continues to rotate about its pivot point 11 in the counterclockwise direction and enters the position III of Figure 3. As a result, the base plate 17 was moved back up out of the support 26. With a reciprocating stroke of the piston rod 5 two punching operations can be performed.

LIST OF REFERENCE NUMBERS

1

body

2

holder

3

Cylinder pivot bearings

4

pneumatic cylinder

5

piston rod

6

clevis

7

Outward direction (arrow)

8th

Inward direction (arrow)

9

long rotary lever

10

upper bearing of the rotary lever

11

pivot point

12

recess

13

Toggle joint

14

short pivoting lever

15

Toggle support

16

holder

17

baseplate

18

table

19

uplink

20

downward direction

21

column guide

22

holding part

23

compression spring

24

tool punch

25

Axle of the tool punch

26

support

27

hole

28

Top edges of the column

29

metal band

30

perforated disc

I

rest position

II

processing position

III

rest position

Claims (3)

1. Apparatus for punching, stamping and/or shaping flat elements (29) comprising a base body (1) with table (18) and support (26) for the flat element (29) and a base plate (17) which carries a tool punch (24) and which is movable by means of a drive for carrying out the working operation towards the support (26) into a working station (II) for engagement of the tool punch (24) with the support (26) and away from the support (26), wherein coupled between the drive (4, 5) and the base plate (17) is at least one long rotary lever (9) which is pivotable about a stationery pivot point (11, 45) fixed to the base body, which rotary lever (9) moves the base plate (17) from a rest position (I) in which the tool punch (24) is out of engagement with the support (26) substantially without a build-up of pressure to shortly before the working position (II) and then over a short distance, producing a high pressure between the base plate (17) and the flat element (29), into the working positions (III) and upon further activity of the drive (4, 5) moves the base plate (17) over regions substantially without a build-up of pressure back into the rest position (I, III) again in the reverse direction of movement, wherein at its one end the long rotary lever (9) is coupled by way of an elbow lever joint (13) to an end of a short pivotal lever (7) whose other end is coupled to the base plate (17) by way of an elbow lever bearing (15) and wherein the long rotary lever (9) is longer than the short pivotal lever (14), characterised in that the drive (4, 5) is mounted to the other end of the long rotary lever (9) in such a way that the drive (4, 5) is disposed axially outside from the pivot point (11).
2. Apparatus according to claim 1 characterised in that the axis (5; 45) of the drive (4, 5) is perpendicular to the axis of the tool punch (24).
3. Apparatus according to claim 1 or claim 2 characterised in that the linear direction of movement (19, 20) of the base plate (17) is predetermined by a column guide (21) operative between the base body (1) and the base plate (17) and that the drive (4, 5) has a drive means (5) which oscillates linearly on its axis.

Images