EP3967512B1 - Device for embossing films - Google Patents

Description

The invention relates to a device for embossing foils, with a base embossing plate and a counter-embossing plate, the surfaces facing one another are each at least partially planar and for embossing a foil lying between them in parallel alignment of their at least partially planar surfaces to one another on the one hand and on the other hand from one another are arranged so that they can be moved away, the base embossing plate being provided on its side facing the counter-embossing plate with a plurality of embossing inserts for embossing a plurality of blanks to be punched out of the film and the embossing inserts being designed and arranged in such a way that they each have one when embossing the film Corresponding embossing area arranged on the side of the counter-embossing plate facing the base embossing plate interacts.

When we talk about embossing a film, this generally also means deforming films. Smooth films can be embossed or deformed, but also pre-embossed or pre-formed films.

Foils in the packaging sector, also known as circuit boards, typically have a thickness between 10 and 150 µm and can be provided with a wide variety of embossings. These embossings can be carried out over the entire surface, partially or as an edge embossing. The reason for these embossings is typically to ensure the separation of the films when they are provided for their attachment to, for example, a container in the form of a film stack, as explained below.

Such films, also called sealing films, are used in the packaging industry for a variety of different products, for example as closures for corresponding packaging containers such as cups or boxes. The sealing films are often obtained by punching out appropriate shapes from a band-shaped material. The material used can be, for example, aluminum foil, plastic foil or composite materials made of plastic and aluminum. The material is often printed on at least one or both sides. To close packaging containers, the sealing films are applied to the Container typically glued or welded on. For this purpose, the films can be provided with a heat-sealing lacquer layer on the side facing the packaging container, for example.

After punching out a shape corresponding to the opening of the packaging container to be closed from a strip material, the resulting shaped pieces are usually stacked. To close the packaging containers, the shaped pieces provided, for example, as lids, are removed from the stack using suitable gripping systems, such as vacuum grippers, and arranged on the opening of the packaging container to be closed. Depending on the attachment system used, such as using heat sealing lacquer, the shaped pieces intended as lids are then connected to the packaging container under the influence of pressure and/or heat. To prevent several shaped pieces from sticking together when the shaped pieces are lifted from the stack, it is known from the prior art to provide the shaped pieces with an embossing in the edge area, which prevents the individual shaped pieces from sticking together. It is also known that embossings are partially left out in order to achieve better readability with barcode scanners. In order to carry out these various embossings, methods using engraved rollers or embossing plates are known. These embossings can also be carried out controlled by tactile marks for the printed image.

A frequently occurring problem is that the foils used to be embossed can have differences in material thickness of up to 5 µm across the embossing width. As a rule, 2 to 18 blanks to be punched out are arranged across the embossing width. Therefore, in many cases there are different embossing depths for the different punched out boards. This has negative effects on the unstackability and the stability of a stack of circuit boards manufactured in this way. If, for example, the embossing depth of the individual blanks fluctuates greatly in the case of pure edge embossing, a stable stack of blanks cannot be formed, which can lead to significant problems on the filling system - targeted removal is often not possible.

The EP 3 321 097 A1 relates to a device and a method for multifunctional foil stamping. In particular, the present invention relates to a device and a method for the multifunctional embossing of sealing films for packaging, wherein the device has a basic embossing element and a detachably arranged alternating embossing element. The base embossing element creates an edge embossing of the sealing film and the alternating embossing element creates an embossed image that conveys haptically perceptible information.

The EP 1 099 509 A1 relates to a method for marking workpieces on punching machines, wherein a marking tool is pressed onto or into the surface of a plate-shaped workpiece which can be displaced in its plane by means of a punching stroke, in which the marking tool has a tool tip which, after being pressed onto or into the workpiece, is pressed into is held in a marking position, the workpiece is moved in its plane according to the contours of the symbol to be marked or labeled and then the tool tip is moved back to its rest position, whereby, if necessary, after a corresponding shift in the position of the workpiece, the marking process is carried out in accordance with the number of symbols to be carried out markings is repeated.

Based on this, the object of the invention is to provide a device for embossing thin-walled films that comes closer to the goal of ensuring an embossing depth that is independent of the material thickness of the film.

This task is solved by the subject matter of patent claim 1. Preferred further training can be found in the subclaims.

According to the invention, a device for embossing foils is therefore provided, with a base embossing plate and a counter-embossing plate, the mutually facing surfaces of which are at least partially flat and which are used to emboss a foil lying between them in parallel alignment of their at least partially flat surfaces to one another on the one hand and on the other hand are arranged to be movable away from each other, the base embossing plate being provided on its side facing the counter-embossing plate with a plurality of embossing inserts for embossing a plurality of blanks to be punched out of the film and the embossing inserts being designed and arranged in such a way that they are each embossed when embossing the film a corresponding embossing area arranged on the side of the counter-embossing plate facing the base embossing plate, characterized in that each embossing insert means a separate embossing insert retainer in the direction normal to the at least partially flat surface of the base embossing plate is held movably on the base embossing plate by a predetermined amount relative to the base support plate, is cushioned relative to the base embossing plate by means of its own embossing insert suspension and by means of its own embossing insert guide in the cushioned movement made possible thereby is guided to the base embossing plate.

It is therefore an essential aspect of the invention that a device for embossing foils, which is otherwise constructed in a conventional manner, is provided on its base embossing plate with such embossing inserts, each of which has its own embossing insert retainer, its own embossing insert spring and its own embossing insert guide. The fact that each embossing insert is provided with its own embossing insert retainer, with its own embossing insert suspension and with its own embossing insert guide means that devices are provided separately for each embossing insert that only interact with this embossing insert and not with any other. In this way, the invention allows the movement of each embossing insert when embossing the film to be independent of the movements of the other embossing inserts. In particular, this enables the embossing inserts to behave in such a way that they "react" independently of one another to different film thicknesses, so that essentially the same embossing depth occurs despite the different thicknesses. If the film to be embossed has differences in its material thickness across its surface, this can be compensated for by the separate storage, suspension and guidance of the individual embossing inserts. Fluctuations in the film thickness, which would otherwise have led to different embossing depths, can thus be compensated for. In the best case, practically the same embossing depth can be achieved with every embossing insert.

The embossing insert retainer ensures the basic attachment of the embossing insert to the base embossing plate. This attachment is such that the embossing insert is basically movable relative to the base embossing plate, namely a movement in the normal direction to the at least partially planar surface of the base embossing plate is possible. This corresponds to a movement of an embossing insert relative to the base embossing plate in a direction parallel or anti-parallel to the direction in which the base embossing plate and the counter-embossing plate are moved towards one another for embossing the film. This means that every embossing insert during embossing, namely when the foil is between a respective embossing insert and a corresponding embossing area is pressed onto the counter-embossing plate, a certain "backward" of the respective embossing insert towards the base carrier plate is made possible. This evasion or retreat of the respective embossing insert takes place in a controlled manner due to the embossing insert suspension assigned to the respective embossing insert in combination with the respective embossing insert guide, so that even with different material thicknesses across the surface of the foil to be embossed, there are differences in the embossing depths for the different ones Embossing inserts can be reduced or avoided entirely.

For this purpose, the embossing insert retainers can be designed in different ways. According to a preferred development of the invention, however, the embossing insert retainers each have a damping device for dampening the possible movement of the respective embossing insert relative to the base embossing plate. Such a damping device therefore offers a certain resistance to the movement of the respective embossing insert, which makes the movement of the embossing insert relative to the base embossing plate more controllable.

For this purpose, different damping devices can be provided. According to a preferred development of the invention, however, the damping device each comprises a spring bolt and/or a damping disk. It is particularly preferred that the embossing inserts are each held on the base embossing plate by means of a fastening device, the fastening device being guided through the damping device. If, for example, in connection with this preferred embodiment of the invention, a spring bolt is provided in combination with a damping disk as a damping device, a screw is preferably guided through these components, with which the respective embossing insert is fastened to the base embossing plate.

Different designs are also possible for the embossing insert guides. According to a preferred development of the invention, the embossing insert guides each have a column guided in a sleeve. It preferably also applies that the column of a respective embossing insert guide is fastened in the respective embossing insert and the bushing is fastened in the base embossing plate.

With regard to the embossing insert suspension, it is essential that this ensures a certain cushioning of the embossing inserts compared to the base embossing plate. For this purpose, a respective embossing insert suspension is preferably designed in such a way that it has an elastic element attached to the respective embossing insert. Furthermore, according to a preferred development of the invention, it is provided that each embossing insert is provided with a plurality of embossing insert guides and/or with a plurality of embossing insert springs. In addition, according to a preferred development of the invention, the shape of the embossing inserts is essentially round, with the embossing insert retainer being arranged centrally in each embossing insert. In this way, a particularly stable holding and guidance of the embossing inserts on the base embossing plate is ensured.

The device according to the invention for embossing films can also be designed differently with regard to the transport of the film to be embossed and the arrangement of the embossing inserts. According to a preferred development of the invention, however, it has a transport device with which the film to be embossed can be moved in a transport direction relative to the base embossing plate, with at least part of the plurality of embossing inserts being arranged next to one another in a direction perpendicular to the transport direction. In other words, this means that, according to this preferred development of the invention, at least some of the embossing inserts are arranged in width perpendicular to the working direction given by the transport direction of the film. According to a preferred development of the invention, the embossing inserts, which are arranged next to one another in a direction perpendicular to the transport direction, are at least partially offset from one another in the transport direction. Such an offset arrangement makes it possible to arrange the largest possible number of embossing inserts on the surface provided by the base embossing plate, in the case of essentially round embossing inserts, for example in the form of a practically hexagonal arrangement of the embossing inserts to one another, which leads to a practically optimal utilization of the existing area.

As far as the embossing areas in the counterplate corresponding to the embossing inserts provided in the base embossing plate are concerned, these can in principle be designed in a conventional manner. According to a preferred development of the invention, in this context the embossing areas corresponding to the embossing inserts provided in the base embossing plate are considered to be releasably fastened in the counter plate Inserts are designed. In particular, the embossing areas designed as such inserts can be screwed into the counter plate. According to a preferred development of the invention, it also applies that the inserts are mounted in the counterplate without springs, and are preferably screwed into the counterplate without springs.

Below we will explain the invention in further detail using a preferred exemplary embodiment with reference to the drawings.

Fig. 1

schematisch ein System zum Prägen von Folien und Ausstanzen von Platinen mit einer Vorrichtung zum Prägen von Folien gemäß einem bevorzugten Ausführungsbeispiel der Erfindung,

Fig. 2 a-d

die Vorrichtung zum Prägen von Folien aus Fig. 1 in unterschiedlichen Ansichten,

Fig. 3

einen Prägeeinsatzrückhalter der Vorrichtung zum Prägen von Folien gemäß dem vorliegend beschriebenen bevorzugten Ausführungsbeispiel der Erfindung in einer Schnittdarstellung,

Fig. 4

eine Prägeeinsatzführung der Vorrichtung zum Prägen von Folien gemäß dem vorliegend beschriebenen bevorzugten Ausführungsbeispiel der Erfindung in einer Schnittdarstellung und

Fig. 5

eine Prägeeinsatzfederung der Vorrichtung zum Prägen von Folien gemäß dem vorliegend beschriebenen bevorzugten Ausführungsbeispiel der Erfindung in einer Schnittdarstellung,

Show in the drawings

Fig. 1

schematically a system for embossing foils and punching out circuit boards with a device for embossing foils according to a preferred embodiment of the invention,

Fig. 2 ad

the device for embossing foils Fig. 1 in different views,

Fig. 3

an embossing insert retainer of the device for embossing foils according to the presently described preferred embodiment of the invention in a sectional view,

Fig. 4

an embossing insert guide of the device for embossing foils according to the preferred exemplary embodiment of the invention described here in a sectional view and

Fig. 5

an embossing insert suspension of the device for embossing foils according to the preferred exemplary embodiment of the invention described here in a sectional view,

Out of Fig. 1 an embossing and punching system 100 can be seen schematically, with which embossed sealing lids and punched out of a web-shaped film 17, such as an aluminum foil or an aluminum/plastic composite film, can be made. For this purpose, the system 100 has a transport device 16, which first feeds the web-shaped film 17 to an embossing device 1. The embossing device 1 is explained in detail below. The foil 17 embossed by means of the embossing device 1 is then fed to a punching device 19, by means of which embossed foil elements, also referred to as blanks, are punched out. The embossed and punched out film elements are finally stacked in a stack 20 and are therefore available for further processing.

For a detailed description of the embossing device 1 according to the present preferred embodiment of the invention, reference is made below Fig. 2a , which shows the embossing device 1 in a section, Fig. 2b , which shows the embossing device 1 in a top view, partly in section Fig. 2c , which shows the embossing device 1 in a side view along its long side and on Fig. 2d , which shows the embossing device 1 in a side device along its short side. Like, for example Figure 2a As can be seen, the embossing device has a base embossing plate 2 and a counter embossing plate 3. Most of the surfaces of the base embossing plate 2 and the counter-embossing plate 3 are formed by flat sections that lie parallel to one another, in the in Fig. 2a shown sectional view, namely run horizontally. The base embossing plate 2 is connected to the counter-embossing plate 3 with the aid of embossing guides 21 in such a way that the base embossing plate 2 and the counter-embossing plate 3 can be moved towards one another in parallel alignment with one another and away from one another on the other hand. By moving the base embossing plate 2 away from the counter-embossing plate 3, the embossing device 1 is practically opened, so that the film 17 to be embossed can be guided between the base embossing plate 2 and the counter-embossing plate 3. For the actual embossing, the base embossing plate 2 and the counter-embossing plate 3 are moved towards each other, so that the actual embossing process of the film 17 between the base embossing plate 2 and the counter-embossing plate 3 finally occurs.

For this embossing process, the base embossing plate 2 is provided with a plurality, in this case eight, embossing inserts 4, which correspond to eight embossing areas 5 in the counter embossing plate. These embossing areas 5 in the counter-embossing plate 3 are in the present case designed in the form of inserts which are screwed into the counter-embossing plate 3 in an unsprung manner, with the help of screws 18. The mutually facing surfaces of the embossing areas 5 and the embossing inserts 4 are like those of conventional embossing devices known, designed in such a way that it occurs during the actual embossing process The desired embossing is achieved between the foil lying between the embossing inserts 4 and the embossing areas 5.

Like in particular Fig. 2b removable, the embossing inserts 4 and thus also the embossing areas 5 are perpendicular to the in Fig. 2b arranged next to each other in the transport direction T marked with an arrow. In addition, the embossing inserts 4 and thus also the embossing areas are also arranged offset from one another in the transport direction. This leads to practically optimal utilization of the available space.

It is now essential that the embossing device 1 according to the preferred exemplary embodiment of the invention described here has such embossing inserts 4, each of which is in the normal direction by means of its own embossing insert retainer 6 Fig. 2b i.e. perpendicular to the plane of the drawing, relative to the flat surfaces of the base embossing plate 2, they are held movably on the base embossing plate 2 by a predetermined amount, are cushioned relative to the base embossing plate 2 by means of their own embossing insert suspension 7 and by means of their own embossing insert guide 8 in the cushioned movement made possible thereby are guided to the base embossing plate 2.

The embossing insert retainer 6 ensures the basic attachment of the embossing insert 4 to the base embossing plate 2, in such a way that a certain movement of the embossing insert 4 remains possible. This corresponds to a movement of the embossing insert 4 relative to the base embossing plate 2 in a direction parallel or anti-parallel to the direction in which the base embossing plate 2 and the counter-embossing plate 3 are moved towards one another for embossing the film 17. This means that each embossing insert 4 during embossing, namely when the film 17 is pressed between a respective embossing insert 4 and a corresponding embossing area 5 on the counter-embossing plate 3, allows a certain "backward" of the respective embossing insert 4 towards the base support plate 2 becomes.

In this way, even with different material thicknesses across the surface of the film 17 to be embossed, differences in the embossing depths of the different embossing inserts 4 can be reduced or completely avoided. Specifically, each of the eight embossing inserts 4 has a centrally arranged embossing insert retainer and three embossing insert guides 8 and six embossing insert suspensions 7. These are designed here as described below.

Fig. 3 shows such an embossing insert retainer 6 in section. It can be seen that the embossing insert retainer 6 has a damping device 9 for dampening the possible movement of the embossing insert 4, on which it is provided, relative to the base embossing plate 2. The damping device 9 comprises a spring bolt 10 and a damping disk 11. A fastening device 12 in the form of a screw is passed through the spring bolt 10 and damping disk 11, with which the respective embossing insert is held on the base embossing plate 2. The fact that this holder allows a certain movement of the embossing insert 4 relative to the base embossing plate 2 is due to the spring bolt 10 and the damping disk 11.

Fig. 4 now shows an embossing insert guide 8, also in section. It can be seen that the embossing insert guide 8 has a column 14 guided in a sleeve 13. The column 14 is fastened in the respective embossing insert 4, while the sleeve 13 is held in the base embossing plate 2.

Out of Fig. 5 Finally, a sectional view of the embossing insert suspension 7 used here can be seen. It can be seen that the embossing insert suspension 7 has an elastic element 15 attached to the respective embossing insert 4. This elastic element is preferably made of a rubber material.

Claims (12)

1. A device for embossing foils, comprising a base embossing plate (2) and a counter embossing plate (3), the surfaces of which facing one another are respectively at least partially planar and which for embossing a foil lying between them are arranged so as to be movable on the one hand towards one another and on the other hand away from one another in parallel alignment of their at least partially planar surfaces, wherein the base embossing plate (2) is provided on its side facing the counter embossing plate (3) with a plurality of embossing inserts (4) for embossing a plurality of blanks to be punched out of the foil (17), and wherein the embossing inserts (4) are configured and arranged so that during the embossing of the foil (17) they cooperate respectively with a corresponding embossing region (5) arranged on the side of the counter embossing plate (3) facing the base embossing plate (2),
   characterised in that each embossing insert (4) is held on the base embossing plate (2) by means of its own embossing insert retainer (6) so as to be movable by a predetermined amount relative to the base embossing plate (2) in perpendicular direction to the at least partially planar surface of the base embossing plate (2), and is spring-mounted by means of its own embossing insert spring system (7) relative to the base embossing plate (2) and is guided by means of its own embossing insert guide (8) during the thereby enabled sprung movement relative to the base embossing plate (2).
2. The device according to claim 1, characterised in that the embossing insert retainers (6) comprise respectively a damping device (9) for damping the possible movement of the respective embossing insert (4) relative to the base embossing plate (2).
3. The device according to claim 2, characterised in that the damping devices (9) comprise respectively a spring bolt (10) and/or a damping plate (11).
4. The device according to any one of the preceding claims, characterised in that the embossing inserts (4) are held respectively on the base embossing plate (2) by means of a fastening device (12), wherein the fastening devices (12) are guided respectively through the respective damping device (9).
5. The device according to any one of the preceding claims, characterised in that the embossing insert guides (8) respectively comprise a column (14) guided in a bush (13).
6. The device according to claim 5, characterised in that the column (14) is fastened in the respective embossing insert (2) and the bush (13) is fastened in the base embossing plate (2).
7. The device according to any one of the preceding claims, characterised in that the embossing insert spring systems (7) comprise respectively an elastic element (15) attached to the respective embossing insert (4).
8. The device according to any one of the preceding claims, characterised in that each embossing insert (4) is provided with a plurality of embossing insert guides (8) and/or with a plurality of embossing insert spring systems (7).
9. The device according to any one of the preceding claims, characterised by a transport device (16), by which the foil (17) to be embossed can be moved in a transport direction relative to the base embossing plate (2), wherein at least a portion of the plurality of embossing inserts (4) are arranged next to one another in a direction perpendicular to the transport direction.
10. The device according to claim 9, characterised in that the portion of the plurality of embossing inserts (4) which are arranged next to one another in a direction perpendicular to the transport direction are arranged at least partly offset relative to one another in the transport direction.
11. The device according to any one of the preceding claims, characterised in that the embossing areas (5) corresponding to the embossing inserts (4) provided in the base embossing plate (2) are configured as inserts which are fixed detachably in the counter embossing plate (3).
12. The device according to claim 11, characterised in that the inserts are not spring-mounted in the counter embossing plate (3).

Images