EP2862684B1 - Punching machine with device for adjustment - Google Patents

Description

The invention relates to a flat bed punching and / or embossing machine according to the preamble of claim 1 and claim 9.

State of the art

Punching is the term used to refer to cutting with self-contained geometric cut shapes, which can be circular, oval or polygonal as well as all kinds of fantasy shapes. Practices used in postpress, such as punching with punch, corner repulsion and register punching, are also included in this area. The punching takes place against a punching pad or against a stamp, in some cases there are also shearing processes. Packaging materials made of paper, cardboard, cardboard or corrugated cardboard are mainly punched in sheet format but also as sheets. Materials such as foil (in-mold), various thin plastics or aluminum foil can also be processed accordingly. In the punching process, crease lines or blind embossing can also be introduced into the panel. This complex process makes it indispensable to punch the sheets individually. Since the end products are sophisticated packaging with regard to technical and graphic design (e.g. packaging for cosmetics, cigarettes, pharmaceuticals, food, etc.), special requirements are not only placed on the packaging materials themselves, but also punching tools for optimal results with the smallest tolerances and extremely precise and reliable punching machines required. Flatbed punching best meets these requirements.
With flatbed sheet punching machines, the sheets that are printed and stacked on a pallet are fed to the punching machine. In the machine, the sheets to be punched are aligned precisely in an alignment device, taken over by a gripper carriage and exactly in the punching device between a fixed lower table and an upper table that can be moved vertically by means of eccentric gears positioned. Alternatively, machines are known in which the upper table is stationary and the lower table is moved against the upper table by means of a toggle for the punching process. Also known are flatbed web punching machines which process webs coming from web printing machines inline.

In known sheet punching and embossing machines which are used for punching, breaking out, embossing and depositing sheets of paper, cardboard and the like, it is known to move the sheets through the individual stations of the machine by means of gripper carriages. Each gripper carriage has a gripper bridge to which grippers are attached, which grip the sheets at a front end. A gripper carriage also has side carriages, which are connected to endless chains of the transport system and by which the gripper carriages are moved through the machine. This type of movement of the sheets through the machine enables continuous work in the individual stations of the machine arranged one behind the other, in particular the punching, stripping and blanking station.

Such a flat bed punch is for example from the DE 30 44 083 A1 known. The two tables, also referred to as crucibles, are equipped with cutting and creasing tools or corresponding counter-tools, with which the sheets are punched out from the sheets that are intermittently guided between the table surface and at the same time the grooves necessary for clean folding are pressed in. In the subsequent stripping device, the waste is removed mechanically using stripping tools. Depending on the equipment of the machine, the punched blanks can finally be separated in a blanking device provided for this purpose.
In order to obtain high quality products, the punching pressure in the sheet punching and embossing machine must be able to be adjusted depending on the sheet to be processed.

Like in the DE 30 44 083 C3 described, this is done by moving wedge-shaped steel plates. These steel plates are located between the eccentric shafts and the driven upper table. By moving the wedge-shaped steel plates, the distance between the moving upper table and the fixed lower table, and thus the punching force, is changed.

The various devices for setting the punching force according to the prior art have in common that the punching force can only be set globally, ie based on the entire area of the crucible. Due to the design, however, all punching and embossing machines according to the prior art have an uneven punch force distribution over the surface of the crucible. The punching force is introduced via individual force introduction points and is therefore not applied to the entire crucible surface. Depending on the rigidity of the crucible, there is a deformation, which in turn results in an uneven punch pressure distribution over the area of the crucible. Differences in the height of the punching or creasing knives as well as the wear of the knives also cause an uneven punching pressure distribution. The unequal punching pressure, in turn, causes the cutting knives of the punching tool to be cut improperly or the scoring of the stamping tool to produce inadequately pronounced scoring.
According to the state of the art, this problem is solved by placing the punching and creasing knives individually under them. Depending on the deviation from the nominal punching force, the punching and creasing knives are glued to the back of the tool with paper or plastic strips of different thicknesses. This so-called dressing is very time-consuming and must be done when the machine is at a standstill. Depending on the number of punching and creasing knives and the shape to be punched, dressing can take several hours. As a result, the high set-up time reduces machine productivity.

The DE 35 31 114 A1 describes a method and a device for pressurizing a press for producing embossing tools. The press is operated separately and independently of a sheet punching and / or embossing machine. The press has a large number of hydraulic pistons that support a pressure plate. The pressure plate is used to stamp the tools. The pistons can be controlled electrically via a control panel, which means that the pressure build-up on the pressure plate can be varied precisely and specifically.

The DE 39 07 826 C2 describes a device for producing punching tool assemblies, namely an impression machine. In order to be able to move the punching tool preparation into the impression machine, is in one first step recorded the topography of the crucible of the punching machine. The topography of the crucibles is then simulated in the impression machine. This enables the punching tools to be prepared in the impression machine and the punching machine to be able to continue to be operated during this punching operation. However, this does not reduce the effort required for preparing the punching tools.

The DE 10 2007 014 317 A1 discloses a sheet punching and embossing machine with a punching station, the crucible of which is provided with a device for regulating the punching or embossing pressure. Several actuator elements such as piezo elements, hydraulic chambers or electric motors are distributed over the device.

Task

The object of the present invention is to provide a flat bed punching and / or embossing machine which reduces the disadvantages of the prior art and which reduces the set-up time and thus increases the productivity of the machine.

This object is achieved by flat-bed stamping and / or embossing machines with the features of claim and claim 9.

The flat bed punching and / or embossing machine according to the invention for processing flat elements, in particular made of paper, cardboard, cardboard or plastic, has a punching and / or embossing station with an upper table and a lower table, one of which can be moved and at least one with one Stamping and / or embossing tool is equipped. According to the invention, the lower table has a plurality of metal blocks arranged next to one another in a matrix-like manner, in particular cuboidal ones, each metal block having an independently controllable heating device for the targeted heating or heating of a respective metal block for dressing the punching and / or embossing station by locally deforming the surface of the lower table . The heating devices of the metal blocks are advantageously controlled in such a way that, due to the thermal expansion of the metal blocks, there is a deformation of the lower table, which corresponds to a particular need for dressing.

In a particularly advantageous and therefore preferred development of the flat-bed punching and / or embossing machine according to the invention, a respective heating device is designed as a heating cartridge with a control unit, with a respective heating cartridge, such as, for. B. offered by the Watlow company under the product name "firerod", in particular has a heatable resistance wire. Such cartridge heaters are inexpensive, clever to install, robust and precisely controlled.

It is particularly advantageous if a bus system is provided for controlling the heating cartridges, with the control unit of a heating cartridge being connected via data transfer technology to a machine controller via the bus system. With this control it is achieved that a respective metal block can be heated in such a way that thermal expansion and consequently a necessary dressing result.

In an advantageous development of the flat-bed punching and / or embossing machine according to the invention, it has a data memory for storing a machine-dependent and / or a tool-dependent dressing requirement and the preparation requirement can be converted into a heat distribution, such that the heating cartridges can be controlled individually by the machine controller, that the heating of the heating cartridges causes the metal blocks to expand and the tools to be prepared.

In an advantageous embodiment variant, the metal blocks are designed as aluminum cuboids.

Furthermore, it is considered advantageous if an insulation layer is provided as thermal insulation between the individual metal blocks. The thickness or effectiveness of the insulation layer can be designed differently, depending on the position of the metal block. So z. B. a metal block located at the edge have a thinner insulation layer than a metal block surrounded by further metal blocks. The insulation layer prevents heat from moving from one metal block to another adjacent metal block can be transferred. In an advantageous further development, a respective metal block can be provided with a cooling element, in particular on its lower end face. The cooling element can be a metal plate, for example, which dissipates the heat introduced by the heating devices.

In an advantageous development, a respective heating cartridge has a temperature sensor and can be regulated via the bus system.

In order to enable easier maintenance and interchangeability of the metal blocks, several metal blocks can be combined to form a unit, in particular a bolt. A respective latch can be individually connectable to the under table.

In an alternative embodiment, the flat bed punching and / or stamping machine has a punching and / or stamping station with an upper table and a lower table. According to the invention, in the area of the lower table or behind an upper tool of the upper table, a hollow chamber plate with a plurality of chambers arranged next to one another in a matrix is provided, the chambers being filled with a rheological liquid and the viscosity in a respective chamber by means of a current-conducting bus system by changing the Rheology of the fluid can be individually adjusted. By precisely controlling the viscosity in the respective chambers, the punching and / or embossing station can be prepared in an advantageous manner.

Different types of valves can be used: controllable micro valves which are known from the field of active microfluidics and can be constructed, for example, from single-crystal silicon, can connect the chambers in each case. After the conditions required for the preparation have been set, the valves remain closed during a respective punching process. When changing the order, the micro valves are opened, the conditions are determined anew and the pressure in each chamber is set.
Another embodiment is check valves or check valves. These form a kind of flap between the chambers. These flaps allow the hydraulic fluid to get into the adjacent chambers, for which two flaps, one in each direction, are required in order to variably regulate the pressure level in the chambers. The flaps should be able to be actively locked and opened. Another approach consists in the use of pressure valves or pressure relief valves or membranes: the chambers are each connected via two pressure valves or membranes and the hydraulic fluid is able to do this due to its specific properties, solely through the influence of the dynamic pressure conditions during a particular punching process Establish the pressure level in the chambers so that the required dressing is achieved. In this case, control of the valves or membrane could be dispensed with.
In all variants, all of the chambers are connected to one another by the aforementioned embodiments of the valves.

The described invention and the described advantageous developments of the flatbed punching and / or embossing machine also represent advantageous developments of the invention in combination with one another.

With regard to further advantages and embodiments of the invention which are advantageous in terms of construction and function, reference is made to the subclaims and the description of exemplary embodiments with reference to the accompanying figures.

Embodiment

Fig. 1

eine Flachbettstanz- und/oder -prägemaschine in einer Übersichtsdarstellung

Fig. 2

die Metallklötze in einer Detaildarstellung

Fig. 3a

die Metallklötze und ihre Ansteuerung in einer Detaildarstellung

Fig. 3b

einen Riegel von Metallklötzen

Fig. 4

die matrixartige Anordnung der Metallklötze

Fig. 5a

eine Hohlkammerplatte als alternative Lösungsvariante

Fig. 5b

die Hohlkammerplatte gefüllt mit rheologischer Flüssigkeit.

The invention will be explained in more detail with reference to the attached figures. Corresponding elements and components are provided with the same reference symbols in the figures. In order to improve the clarity of the figures, the scale has been omitted.
They show a schematic representation

Fig. 1

a flatbed punching and / or embossing machine in an overview

Fig. 2

the metal blocks in a detailed view

Fig. 3a

the metal blocks and their control in a detailed view

Fig. 3b

a block of metal blocks

Fig. 4

the matrix-like arrangement of the metal blocks

Fig. 5a

a twin-wall sheet as an alternative solution

Fig. 5b

the twin-wall sheet filled with rheological fluid.

In Figure 1 the basic structure of a sheet punching and embossing machine 100 for punching, breaking out, separating sheets and depositing sheets of paper, cardboard, plastic and the like is shown. The punching and embossing machine 100 has a feeder 1, a punching station 2, a stripping station 3 and a boom 4 with a storage and blanking separation station, which are carried by a common machine housing 5 and are enclosed and driven by a main drive 17. The processing stations 2, 3, 4 are accessible from one side, the so-called operator side; the drive train of the sheet punching and embossing machine 100 is located on the opposite side, the so-called drive side. A machine control 15 controls the processes within the punching machine 100.

The sheets 6 are separated by a feeder 1 from a stack 6.1 through a so-called suction head 18, fed to the sheet transport system 7 and gripped at their front edge by grippers attached to gripper bridges of a gripper carriage 8 and intermittently in the sheet transport direction B through the various stations 2, 3 and 4 the punching and embossing machine 100.
The sheet transport system 7 has several gripper carriages 8, so that several sheets 6 can be processed simultaneously in the different stations 2, 3 and 4. The gripper carriage 8 can be driven by a chain drive.

The punching station 2 consists of a lower crucible, a so-called lower table 9, and an upper crucible, a so-called upper table 10. The upper table 10 is mounted such that it can be moved back and forth vertically and is provided with an upper tool 30 with punching and creasing knives. The lower table 9 is fixed in the machine frame and provided with a counter plate 20 for the punching and creasing knives. Alternatively, the upper table 10 can also be stationary and the lower table 9 can be moved. When embossing, stamping tools are used instead of punching and creasing tools, especially in the form of so-called embossing plates. A plurality of metal blocks 101 are integrated in the lower table 9, which bring about the adjustment of the lower table 9. In addition, the under table 9 can be provided with an active cooling 101. As an alternative to the metal blocks 101, in a variant that is not shown, hollow-chamber plates 200 can instead be arranged behind the upper tool 30 and / or behind the lower tool 20, which cause the respective tool 20, 30 to be trimmed.

The gripper carriage 8 transports the sheet 6 from the punching and embossing station 2 into the subsequent stripping station 3, which is equipped with stripping tools 21, 23. In the stripping station 3, the stripping tools 21, 23 do not required waste pieces 11 are pushed out of the sheet 6 downwards, as a result of which the waste pieces 11 fall into a cart-like container 12 inserted under the station or are transported away from there.

From the stripping station 3, the sheet 6 reaches the delivery unit 4, where the sheet 6 is either simply deposited, or at the same time the individual benefits of a respective sheet 6 are separated. For this purpose, the boom 4 has a panel separating tool 21, 23. The boom 4 can also contain a pallet 13 on which the individual sheets 6 or panels are stacked in the form of a stack 14, so that the pallet 13 with the Sheet stack 14 can be moved out of the area of the punching and embossing machine 100. In order not to have to stop the machine 100 during the stack exchange, auxiliary stacking devices can be used.

In Figure 2 the metal blocks 101, which are used for dressing a punched grooved plate 20 and thus for dressing the punching and / or embossing station 2, are shown in more detail. A respective metal block 101 is surrounded by an insulation layer 108a to 108f. As an alternative to the insulation layer 108f attached to the lower end face of the metal block 101, a metal plate can be attached there as a cooling element 110, which serves to dissipate heat introduced by the heating cartridges 104.

A heating cartridge 104 is integrated in a respective metal block 101. This heating cartridge 104 is controlled by a control unit 105, which is also integrated in the metal block 101. A respective control unit 105 can thus specify the temperature to which a respective heating cartridge 104 is heated. This temperature is dependent on a required thermal expansion of a respective metal block 101, which in turn is required for the preparation of the punched groove plate 20 in the area of this metal block 101. The specification of a respective temperature, which is therefore determined by the thermal expansion behavior of the metal blocks 101 and a respective local need for dressing - as in the sectional illustration of Figure 3a shown - transmitted via a bus system 106 to a respective control unit 105 of a metal block 101, for which purpose a unique address 107 is assigned. The required calculation, based on a distribution of the need for preparation, can be carried out by a machine control 15. In an advantageous embodiment variant, a respective metal block 101 can have a temperature sensor 113, so that the actual actual temperature of the metal block 101 can be fed back to the machine controller 15 or a respective control unit 105, so that temperature regulation is made possible. As in Figure 4 are shown, the metal blocks 101 are arranged next to one another in a matrix field 102 in rows m1, m2, ... and columns n1, n2, ... and extend approximately over the surface of the lower table 9 or the punched groove plate 20. As in FIG Figure 3b indicated, a plurality of metal blocks 101 can be combined to form bolts 112, so that the metal blocks 101 can be serviced, repaired and replaced more easily.

Instead of the metal blocks 101 described above, one can also prepare the punching and / or stamping station 2 as in FIG Figure 5a shown hollow chamber plate 200 can be used, which has a plurality of chambers 201 arranged next to one another in a matrix, which are filled with a rheological liquid 202. In an alternative, not shown, the chambers 201 can be designed as honeycomb-shaped, for example hexagonal, chambers.

In Figure 5b is shown in more detail.
The chambers 201 of the hollow chamber plate 200 are filled with a rheological liquid 202. A current finger 206 is connected to a respective chamber 201 for applying a current to the respective chamber 201 for adjusting the viscosity of the rheological liquid 202 in the respective chamber 201. The current fingers 206 are connected to a control unit 105 via a bus system 106 and can be controlled like this. By presetting a certain current, the viscosity in the chamber 201 can be adjusted and a locally required dressing can thereby be brought about.

Reference list

1

Investors

2nd

Stamping and / or stamping station

3rd

Stripping station

4th

Boom, possibly with a depaneling station

5

Machine housing

6

bow

6.1

Sheet stack

7

Sheet transport system

8th

Grab car with grabs

9

Under table / lower crucible

10th

Upper table / upper crucible

11

Pieces of waste

12th

container

13

palette

14

Delivery pile

15

Control with interface and input devices

16

Feed table with a sheet alignment unit

17th

Main drive

18th

Suction head

19th

Lower tool with pins

20th

Punching plate

21

Upper tool with pins or stamps

23

Panel separation grid or stripping board (intermediate tool)

30th

Upper tool (punching tool)

100

Flatbed sheet punching and / or embossing machine (punching machine)

101

Block of metal

102

Matrix field

103

-

104

Heating cartridge

105

Control unit

106

Bus system

107

unique address

108

isolation

108a

Isolation on a peripheral surface of a metal block

108b

Isolation on a peripheral surface of a metal block

108c

Isolation on a peripheral surface of a metal block

108d

Isolation on a peripheral surface of a metal block

108e

Isolation on the top face of a metal block

108f

Isolation on the lower face of a metal block

109

-

110

Metal plate as a cooling element

111

active cooling of the under table

112

Bars made of metal blocks

113

Temperature sensor

200

Twin-wall sheet

201

chamber

202

rheological fluid

203

Hydraulic fluid

204

Valve

m1, m2, ...

Rows of matrix fields

n1, n2, ...

Columns matrix field

B

Sheet transport direction

E

Sheet transport plane

Claims (9)

1. A flat-bed sheet punching and/or embossing machine (100) with a punching and/or embossing station (2) comprising an upper table (10) and a lower table (9), characterized in that the lower table (9) comprises a plurality of metal blocks (101) arranged next to one another in a matrix like manner, wherein each metal block (101) includes an independently controllable heating device (104) for a targeted heating of a respective metal block (101).
2. The flat-bed sheet punching and/or embossing machine according to claim 1,
   characterized in that a respective heating device is a heating cartridge (104) having a control unit (105).
3. The flat-bed sheet punching and/or embossing machine according to claim 2,
   characterized in that a bus system (106) is provided for actuating the heating cartridges (104),
   wherein the control unit (105) of a heating cartridge is connected to a machine control (15) via the bus system (106) by means of data transmission.
4. The flat-bed sheet punching and/or embossing machine according to any one of the preceding claims, characterized in that the flat-bed sheet punching and/or embossing machine (100) has a memory for saving a machine-dependent and/or a tool-dependent alignment demand.
5. The flat-bed sheet punching and/or embossing machine according to any one of the preceding claims, characterized in that the metal blocks (101) are aluminum cuboids.
6. The flat-bed sheet punching and/or embossing machine according to any one of the preceding claims, characterized in that an insulating layer (108) is provided between the metal blocks (101).
7. The flat-bed sheet punching and/or embossing machine according to any one of the preceding claims, characterized in that a respective metal block (101) is provided with a cooling element (110), in particular at its lower end face.
8. The flat-bed sheet punching and/or embossing machine according to any one of claims 3 to 7, characterized in that a respective heating cartridge (104) has a temperature sensor (113) and is controllable via the bus system (106).
9. A flat-bed sheet punching and/or embossing machine (100) with a punching and/or embossing station (2), comprising an upper table (10) and a lower table (9), characterized in that a hollow chamber plate (200) having a plurality of chambers (201) arranged next to one another in a matrix like manner is provided in the region of the lower table (9) or behind an upper tool (30) of the upper table (10), wherein the chambers (201) are filled with a rheological liquid (202), wherein the viscosity in a respective chamber (201) is individually adjustable by means of an electricity-conductive bus system (106).

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