ES2799413T3 - Die cutting machine with alignment device - Google Patents

Abstract

Flat bed stamping and / or embossing machine (100) with a stamping and / or embossing station (2) that has an upper table (10) and a lower table (9), characterized in that the lower table (9) presents a plurality of metal blocks (101) arranged side by side in a matrix fashion, each metal block (101) presenting an independently controllable heating device (104) for directed heating of a respective metal block (101).

Description

DESCRIPTION

Die cutting machine with alignment device

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

State of the art

The cut with geometric shapes of the cut piece closed on themselves that can be circular, oval or polygonal, as well as fantasy shapes of all kinds, is designated as punching. Also, practices developed in the further processing of printing products, such as punching, corner blunting and registration punching, are integrated into this sector. The punching is carried out against a punching base or against a punch, and partially also encompasses cutting processes. Packaging materials made of paper, cardboard, cardboard or corrugated cardboard are mainly stamped in sheet format or as bands. Likewise, materials such as films ( in-mold), various plastic materials or thin aluminum foils can be processed accordingly. However, during the stamping process, also blind grooved or embossed lines can also be produced on the usable part. This complex process makes it essential to individually stamp the sheets. Since final products are demanding packaging with respect to their technical and graphic realization (e.g. packaging for cosmetics, cigarettes, pharmacy, food, etc.), not only are special requirements imposed on the packaging materials themselves, but also For best results, die-cutting tools with very tight tolerances and die-cutting machines that work extremely precisely and reliably are also necessary. Flat bed die cutting optimally meets these requirements.

In flatbed sheet die cutting machines, the printed sheets stacked on a pallet are fed to the die cutting machine. In the machine, the sheets to be punched are oriented exactly adjusted in an orientation device, they are picked up by a gripper carriage and exactly positioned in the punching device between a fixedly mounted lower table and a vertically movable upper table by means of an eccentric mechanism. Alternatively, machines are known in which the upper table is fixed and is moved by means of levers bent against the upper table for the punching process of the lower table. Also, flat bed web die cutting machines are known which further process webs from roll printing machines online.

In known sheet stamping and embossing machines, which are used for punching, tearing, embossing and depositing sheets of paper, cardboard and the like, the resource of moving the sheets by means of gripper carriages through the individual stations of machine. A respective clamp carriage has a clamp bridge to which clamps are attached which grip the sheets at a front end. A gripper carriage furthermore has lateral translation carriages which are connected with endless chains of the transport system and by which the gripper carriages are moved through the machine. Thanks to this type of movement of the sheets through the machine, continuous work is possible in the individual stations of the machine arranged one behind the other, in particular the station for stamping, starting and separating usable parts.

Such a flat-bed die is known, for example, from DE 3044083 A1. The two tables, also referred to as crucibles, are equipped with corresponding cutting and grooving tools or counter tools, with which the usable parts are punched out in the sheet intermittently driven between the surfaces of the tables and, simultaneously, the slots necessary to make a neat fold. In the next starter device, the waste is mechanically removed by means of starter tools. Finally, depending on the equipment of the machine, the punched usable parts can be separated in a device for separating usable parts provided for this.

In order to obtain high-quality products, the stamping pressure on the sheet stamping and embossing machine must be able to adapt to the sheet to be processed.

As described in DE 3044083 C3, this happens due to the displacement of wedge-shaped steel plates. These steel plates are located between the eccentric shafts and the driven upper table. By shifting the wedge-shaped steel plates, the distance between the moved upper table and the fixed lower table, and thus the punching force, is changed.

The various devices for adjusting the punching force according to the state of the art have in common that the punching force can only be adjusted globally, that is, relative to the entire surface of the crucible. However, depending on the construction, in all stamping and embossing machines according to the state of the art, an uneven stamping force distribution occurs on the surface of the crucible. The punching force is applied by means of individual force application points and therefore does not apply to the entire surface of the crucible. Depending on the rigidity of the crucible, a deformation results, again resulting in an uneven punching pressure distribution over the entire crucible surface. Also, differences in the height of the die cutting and grooving blade, as well as blade wear, cause uneven distribution of die pressure. The uneven stamping pressure again causes an unclean cut of the cutting blade of the stamping tool or an insufficiently pronounced gouging of the gouging knife of the embossing tool.

According to the state of the art, this problem is solved by individually shimming the punching and grooving knives. Depending on the deviation from the nominal punching force, the punching and grooving blades are glued from behind to the rear side of the tool with strips of paper or plastic of different thickness. This so-called alignment is time consuming and must be done during machine shutdown. Depending on the number of punching and grooving knives and the shape to be punched, the alignment can take several hours. The long alignment time results in low machine productivity.

DE 3531 114 A1 describes a method and a device for pressing a press for manufacturing embossing tools. The press is in this case operated separately and independently of a sheet stamping and / or embossing machine. The press has a plurality of hydraulic pistons that carry a pressure plate. The pressure plate is used for embossing the tools. The pistons can be electrically actuated by means of a control station, whereby the pressure build-up on the pressure plate can be changed precisely and in a targeted manner.

DE 3907826 C2 describes a device for manufacturing punching tool preparations, namely a molding machine. In order to be able to move the punch tool setting to the molding machine, the topography of the crucibles of the punch machine is detected in a first step. The topography of the crucibles is then simulated on the molding machine. Thus, the punching tools are allowed to be prepared in the molding machine, and the punching machine can be further operated during this alignment. However, this does not reduce the cost of aligning the punching tools.

Document DE 102007 014317 A1 discloses a sheet stamping and embossing machine with a stamping station, the crucible of which is provided with a device for regulating the stamping or embossing pressure. In this case, several actuating elements, such as piezoelectric elements, hydraulic chambers or electric motors, are distributed over the device.

Approach

The aim of the present invention is to create a flat bed stamping and / or embossing machine which reduces the disadvantages of the state of the art and which reduces the alignment time and therefore increases the productivity of the machine.

This objective is achieved by means of flat-bed stamping and / or embossing machines with the characteristics of claim and claim 9.

The flat bed stamping and / or embossing machine according to the invention for processing flat elements, in particular paper, cardboard, cardboard or plastic has a stamping and / or embossing station with an upper table and a lower table, one of which is they movable vertically and at least one other being equipped with a stamping and / or embossing tool. According to the invention, the lower table has a plurality of metal blocks, particularly in the shape of parallelepipeds, arranged one next to the other as a matrix, each metal plug having an independently controllable heating device, to heat or reheat in a targeted manner a respective metal block in order to prepare the station for stamping and / or embossing by local deformation of the surface of the lower table. Advantageously, the heating devices of the metal blocks are activated in such a way that, due to the thermal expansion of the metal blocks, a deformation of the lower table occurs which corresponds to an ever necessary alignment demand.

In a particularly advantageous and therefore preferred development of the flat-bed stamping and / or embossing machine according to the invention, a respective heating device is realized as a heating cartridge with a control unit, with a respective heating cartridge as the for example, the one proposed by the Watlow company under the product name "firerod", in particular a heatable resistance wire. These heating cartridges are inexpensive, easy to assemble, robust and accurate to activate.

It is particularly advantageous if a bus system is provided for activating the heating cartridges, the respective control unit of a heating cartridge being connected by the data transmission technique to a machine control via the bus system. As a result of this activation, it is achieved that a respective metal block can be heated in such a way that thermal expansion results and, as a consequence, a necessary alignment.

In an advantageous development of the flat-bed stamping and / or embossing machine according to the invention, This has a data memory for storing a machine-dependent and / or tool-dependent alignment request and the alignment request can be converted into a heat distribution, such that the heating cartridges can be individually activated correspondingly by the machine control, and that, by heating the heating cartridges, an expansion of the metal blocks is carried out and from there an alignment of the tool.

In an advantageous embodiment variant, the metal blocks are made as parallelepipeds of aluminum.

Furthermore, it is considered advantageous if an insulating layer is provided as thermal insulation between the individual metal blocks. The thickness or effectiveness of the insulating layer can be configured differently, depending on the position of the metal block. Thus, for example, a metal block located at the edge may have a thinner insulating layer than a metal block surrounded by additional metal blocks. The insulating layer means that heat cannot be transmitted from one metal block to another adjoining metal block. In an advantageous development, a respective metal block with a cooling element can be provided, in particular on its lower front surface. The cooling element can in this case be, for example, a metal plate that dissipates the heat introduced through the heating devices.

In an advantageous development, a respective heating cartridge has a temperature sensor and is controllable by the bus system.

To enable easier maintenance and interchangeability of the metal blocks, the respective various metal blocks can be grouped into a unit, in particular a latch. A respective latch can in this case be individually connected to the lower table.

In an alternative embodiment variant, the flat-bed stamping and / or embossing machine has a stamping and / or embossing 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 is provided with a plurality of chambers arranged side by side in a matrix manner, the chambers being filled with a liquid rheological and the viscosity can be individually adjusted in a respective chamber by means of an electrically conductive bus system by varying the rheology of the liquid. By means of locally precise control of the viscosity in the respective chambers, an alignment of the stamping and / or embossing station can advantageously be carried out.

Different types of valves can be used: controllable microvalves that are known from the active microfluidics industry and, for example, can be constructed from monocrystalline silicon and can link the respective chambers. After the necessary ratios for alignment have been set, the valves remain closed during a respective punching process. In a change of order the microvalves are opened, the relationships are determined again and the pressure is adjusted in a respective chamber.

Another embodiment are check valves or check gates. These form a type of gate between the chambers. These gates allow the hydraulic fluid to reach the adjacent chambers, for which two gates are needed, always one per direction, they can regulate the pressure level in the chambers in a variable way. The gates should be capable of being actively interlocked and open.

An additional approach consists in the use of pressure valves or pressure limiting valves or membranes: the chambers are connected respectively by means of two pressure valves or membranes and the hydraulic fluid, due to its specific properties, is in a position to establish the pressure level in the chambers only by the influence of dynamic pressure ratios during a respective punching process, so that the necessary alignment is adjusted. In this case, activation of the valves or membranes could be dispensed with.

In all variants, all chambers are connected to one another by means of the mentioned embodiments of the valves.

The described invention and the described advantageous developments of the flat-bed embossing and / or embossing machine represent advantageous developments of the invention also in combination with each other.

With regard to other advantages and to the constructive and functional aspect of advantageous embodiments of the invention, reference will be made to the dependent claims and to the description of examples of embodiments with reference to the attached figures.

Example of embodiment

The invention should be explained even more clearly with the aid of the attached figures. The elements and components corresponding to each other are provided in the figures with like reference symbols. For the sake For greater clarity of the figures, a faithful scale representation has been renounced.

They show in schematic representation:

Figure 1, a flat-bed stamping and / or embossing machine in a general view representation,

Figure 2, the metal blocks in a detail representation

Figure 3a, the metal blocks and their activation in a detailed representation

Figure 3b, a metal block latch

Figure 4, the matrix-like arrangement of the metal blocks

Figure 5a, a hollow chamber plate as an alternative solution variant

Figure 5b, the hollow chamber plate filled with rheological liquid.

In figure 1, the fundamental structure of a sheet stamping and embossing machine 100 for punching, tearing, separating usable parts and depositing sheets of paper, cardboard, plastic and the like is represented. The stamping and embossing machine 100 has a feeder 1, a stamping station 2, a start station 3 and an extractor 4 with a station for depositing and separating usable parts, which are carried and confined by a common machine housing 5 and are driven by a main drive 17. From one side, the so-called operator side, the processing stations 2, 3, 4 are accessible; On the opposite side, the so-called drive side, is the drive line of the sheet stamping and embossing machine 100. A machine control 15 controls the processes within the stamping machine 100.

The sheets 6 are individualized with respect to a stack 6.1 by means of a feeder 1 through a so-called suction head 18, they are supplied to the sheet transport system 7 and are grasped at their front edge by clamps fixed to some bridges of clamps of a clamp carriage 8 and, in the direction of sheet transport B, are intermittently passed through the different stations 2, 3 and 4 of the stamping and embossing machine 100.

The sheet transport system 7 has several clamp carriages 8, so that several sheets 6 can be processed simultaneously in the different stations 2, 3 and 4. The clamp carriages 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 vertically reciprocatingly movable and is provided with an upper tool 30 with blades of punching and grooving. The lower table 9 is fixedly mounted on the frame of the machine and is provided with a counter plate 20 for the punching and grooving knives. Alternatively, likewise, the upper table 10 may be stationary and the lower table 9 may be movable. During embossing, instead of punching and grooving tools, embossing tools are used, especially in the form of so-called embossing cliches. A plurality of metal blocks 1 are integrated in the lower table 9 which cause the lower table 9 to align. Additionally, the lower table 9 can be provided with an active cooling 101. Alternatively to the metal blocks 101, in a variant not shown , hollow chamber plates 200 may instead be arranged behind the upper tool 30 and / or behind the lower tool 20, causing an alignment of the respective tool 20, 30.

The gripper carriage 8 transports the sheet 6 from the stamping and embossing station 2 to the next starting station 3, which is equipped with starting tools 21, 23. At the starting station 3, with the help of the starting tools 21, 23, unnecessary scrap pieces 11 are detached from the sheet 6 downwards, whereby the scrap pieces 11 fall into a cart-like container 12 inserted below the station or are transferred from there.

The sheet 6 passes from the starting station 3 to the extractor 4, where only the sheet 6 is simply deposited or a separation of the individual usable parts from a respective sheet 6 is simultaneously carried out. The extractor 4 has a separating tool for this. of usable parts 21, 23. The extractor 4 can also contain a pallet 13 on which the different sheets 6 are stacked or usable parts in the form of a stack 14, so that, after reaching a certain stacking height, the pallet 13 with the stack of sheets 14 it can be evacuated from the area of the stamping and embossing machine 100. In order not to have to stop the machine 100 during the stack change, auxiliary stacking devices can be used.

In figure 2, the metal blocks 101 are represented in more detail, which serve for the alignment of a die-cutting grooving plate 20 and, therefore, the alignment of the stamping and / or embossing station 2. A respective metal block 101 is surrounded by an insulating layer 108a to 108f. As an alternative to the insulating layer 108f applied to the lower front surface of the metal block 101, a metal plate can be arranged there as a cooling element 110, which serves to evacuate heat introduced by the heating cartridges 104. A heating cartridge 104 is integrated into a respective metal block 101. This heating cartridge 104 is activated by a control unit 105, which is also integrated in the metal block 101. It is thus possible to predetermine by means of a respective control unit 105 to what temperature a respective heating cartridge 104. This temperature is, in this case, independent of a necessary thermal expansion of a respective metal block 101 which is again necessary to prepare the grooving plate by punching 20 in the area of this metal block 101. The stipulation of a respective temperature, which is therefore conditioned by the thermal expansion behavior of the metal blocks 101 and a respective local alignment demand - as illustrated in the sectional representation of figure 3a - is determined by means of a bus system 106 in a respective control unit 105 of a metal block 101, to what is assigned a unique address 107.

The necessary calculation, starting from an alignment demand distribution, can in this case be carried out by means of a machine control 15. In an advantageous embodiment variant, a respective metal block 101 can be provided with a temperature sensor 113, so that the true actual temperature of the metal block 101 can be communicated to the machine control 15 or to a respective control unit 105, so that a temperature regulation is made possible. As shown in figure 4, the metal blocks 101 are arranged side by side in a matrix field 102 in lines m1, m2, ... and columns n1, n2, ... and extend approximately throughout the entire surface of the bottom table 9 or the die-grooving plate 20. As indicated in Figure 3b, several respective metal blocks 101 can be grouped together to form latches 112, so that the metal blocks 101 can be further maintained, repaired and changed. simple. Instead of the metal blocks 101 described above, to prepare the stamping and / or embossing station 2 a hollow chamber plate 200 shown in FIG. 5a can also be used, which has a plurality of chambers 201 arranged side by side at matrix mode, which are filled with a rheological liquid 202. The chambers 201 may be made in an alternative not shown as honeycomb chambers, eg hexagonal.

In FIG. 5b, the hollow chamber plate 200 is shown in detail. The chambers 201 of the hollow chamber plate 200 are filled with a rheological liquid 202. With a respective chamber 201, a current finger 206 is attached to apply an electric current in the respective chamber 201 to adjust the viscosity of the rheological liquid. 202 in the respective chamber 201. The current fingers 206 are linked to a control unit 105 and can be activated by means of a bus system 106. By stipulating a certain current, the viscosity can be adjusted in the chamber 201 and, thus, locally necessary alignment can be brought about.

Reference symbols list

1 Feeder

2 Stamping and / or embossing station

3 Start station

4 Extractor, possibly with separating station for usable parts

5 Machine housing

6 Sheet

6.1 Stack of sheets

7 Sheet transport system

8 Gripper carriage with gripper

9 Lower table / Lower crucible

10 Upper table / upper crucible

11 Scrap part

12 Container

Pallet

Output stack

Control with interface and input devices

Feeding table with a unit for aligning the sheets

Main drive

Suction head

Bottom tool with pins

Die Cut Grooving Plate

Top tool with pins or punches

Useful part separation grid or starter board (intermediate tool) Upper tool (punching tool)

Flat bed sheet die cutting and / or embossing machine (die cutting machine) Metal block

Matrix field

-Heating cartridge

Control unit

Bus system

Unique address

Isolation

a Insulation on a peripheral surface of a metal block

b Insulation on a peripheral surface of a metal block

c Insulation on a peripheral surface of a metal block

d Insulation on a peripheral surface of a metal block

e Insulation on the upper front surface of a metal block

f Insulation on the lower front surface of a metal block

-Metal plate as a cooling element

Active cooling of the lower table

Metal block latch

Temperature sensor

Hollow chamber plate

Camera

202 Rheological liquid

203 Hydraulic fluid

204 Valve

m1, m2, ... rows of matrix field n1, n2, ... columns of matrix field B direction of sheet transport

E sheet transport plan

Claims (9)

1. Flat bed stamping and / or embossing machine (100) with a stamping and / or embossing station (2) that has an upper table (10) and a lower table (9), characterized in that the lower table ( 9) presents a plurality of metal blocks (101) arranged side by side as a matrix, each metal block (101) presenting an independently controllable heating device (104) for directed heating of a respective metal block (101) . Flat-bed stamping and / or embossing machine according to claim 1, characterized in that a respective heating device is realized as a heating cartridge (104) with a control unit (105). 3. Flat bed stamping and / or embossing machine according to claim 2, characterized in that a bus system (106) is provided to activate the heating cartridges (104), the respective control unit (105) of a heating cartridge being connected to a machine control (15) through the control system. bus (106) by the data transmission technique. Flat-bed stamping and / or embossing machine according to one of the preceding claims, characterized in that the flat-bed stamping and / or embossing machine (100) has a memory for storing a machine-dependent alignment request and / or a demand for alignment depending on the tool. Flat-bed stamping and / or embossing machine according to one of the preceding claims, characterized in that the metal blocks (101) are made as parallelepipeds of aluminum. Flat-bed stamping and / or embossing machine according to one of the preceding claims, characterized in that an insulating layer (108) is provided between the metal blocks (101). Flat bed stamping and / or embossing machine according to one of the preceding claims, characterized in that a respective metal block (101) is provided with a cooling element (110), in particular on its lower front surface. Flat-bed stamping and / or embossing machine according to one of Claims 3 to 7, characterized in that a respective heating cartridge (104) has a temperature sensor (113) and is adjustable via the bus system ( 106). 9. Flat bed stamping and / or embossing machine (100) with a stamping and / or embossing station (2) featuring an upper table (10) and a lower table (9), characterized in that in the area of the lower table (9) or behind an upper tool (30) of the upper table (10), a hollow chamber plate (200) is provided with a plurality of chambers (201) arranged one side by side as a matrix, the chambers (201) being filled with a rheological liquid (202), the viscosity being individually adjustable in a respective chamber (201) by means of an electrically conductive bus system (106).