Forming apparatus and method for forming cups into packaging material

Abstract

To ensure good deformability of a packaging material without having a disadvantageous effect on a forming process and on the packaging material.SOLUTION: A forming device has a die (8) with at least one recess (10), a punch (20) for forming a packaging material (4) into the recess (10), and a hold-down device (12). The hold-down device (12) and the die (8) receive the packaging material (4) between them in a holding region. The die (8) and the hold-down device (12) each have a bearing surface (16, 18) with at least one opening (32, 36), which is in fluid communication with a fluid source (34, 38). An aerostatic bearing (28, 30) is formed between the packaging material (4) and the hold-down device (12) and between the packaging material (4) and the die (8).SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a forming apparatus and method for forming at least one cup into a packaging material. [Background technology]

[0002] The packaging often has at least one cup formed in the packaging material for receiving the product, as is known, for example, from packaging for medical or pharmaceutical products or food or dietary supplements. Such packaging can be formed, for example, by molding the at least one cup by injection molding or by deep drawing the at least one cup into the packaging material.

[0003] In deep drawing, the tools used are frequently heated, especially in the form of dies and pressure devices, to reduce friction between the packaging material and the tools and to counteract wrinkling of the packaging material. However, heating the tools can have a detrimental effect on the forming process and the packaging material, especially in the case of fiber-based packaging materials, which are generally wetted to improve their deformability, and heating can have a detrimental effect on the deformability of the packaging material. Summary of the Invention [Problem to be solved by the invention]

[0004] It is therefore an object of the present invention to provide a molding device and method for molding at least one cup into a packaging material, which ensures good deformability of the packaging material without adversely affecting the molding process and the packaging material. [Means for solving the problem]

[0005] According to one aspect of the invention, a forming device for forming at least one cup into a packaging material comprises a die having at least one recess, a punch configured to form the packaging material into the at least one recess of the die, and a presser device configured to receive the packaging material between the die and the punch in a holding area surrounding the at least one recess of the die. In the holding area, the die has a first bearing surface facing the presser device, and the presser device has a second bearing surface facing the die in the holding area. The first bearing surface has at least one first opening, preferably a plurality, and the at least one first opening is in fluid communication with a first fluid source. Alternatively or additionally, the second bearing surface has at least one second opening, preferably a plurality, and the at least one second opening is in fluid communication with the first fluid source or a second fluid source.

[0006] In this way, a fluid supply between the first or second bearing surface and the packaging material is possible, which allows the packaging material to be aerostatically supported in the forming device. This allows the contact and therefore the friction between the packaging material and the die or the holding device during forming, especially during deep drawing, to be reduced. The reduced friction also has the effect that heating of the die or the holding device to reduce friction is not necessary, which avoids the adverse effects of heat on the packaging material and the forming process. Continuous energy input for heating the die and the holding device is not necessary, which is advantageous from an economic and environmental point of view. In a preferred embodiment, the die and the holding device are therefore unheated.

[0007] Furthermore, reduced friction allows for greater retention of the packaging material by the die and hold-down devices, resulting in less wrinkling of the packaging material and improved packaging quality.

[0008] As a rule, the forming device is configured to form at least one cup. Particularly preferably, the forming is achieved by deep drawing the packaging material. Therefore, all the features and embodiments described herein are particularly also relevant to the deep drawing of the packaging material, from which at least one cup is formed. However, other processes, such as, for example, press forming, can also be used.

[0009] The forming device may be configured to simultaneously form multiple cups into the packaging material. For this purpose, at least one recess of the die may have multiple recesses. The forming device may have multiple punches or the punch may have multiple protrusions, each protrusion being configured to form the packaging material into a respective recess of the multiple recesses of the die. The holding device preferably surrounds each recess of the multiple recesses of the die. The forming device is described below as a representative example in the case of having one recess and one punch, but these features apply equally to embodiments having multiple recesses, multiple punches or protrusions, and corresponding holding devices.

[0010] The packaging material may be made of a material selected from the group consisting of metal, for example aluminum, plastic, in particular thermoplastic, or fiber-based material, for example paper, cardboard or textile. The packaging material may consist entirely of a fiber-based packaging material or may have a coating, for example of plastic.

[0011] The packaging material is substantially flat in shape. The packaging material can be provided in the form of a web, i.e. as a packaging material web, or as a blank, in each case as one package. A packaging material web is particularly suitable for film-type packaging materials.

[0012] The at least one first opening or the at least one second opening allows for a fluid to be supplied into the holding area between the die, the hold-down device and the packaging material. The fluid is preferably a gas, particularly preferably air. The first and second fluid sources are preferably compressed air sources configured to discharge pressurized air, i.e. compressed air.

[0013] The first plurality of openings may also be in fluid communication with a plurality of fluid sources, and the second plurality of openings may independently be in fluid communication with a plurality of fluid sources, as described in more detail below with reference to preferred embodiments, however, the first and second fluid sources may also be of unitary construction.

[0014] The supply of fluid allows the formation of a hydrostatic gas bearing. The die and / or the hold-down device are configured to result in the formation of a hydrostatic gas bearing in the holding area. Typically, a hydrostatic gas bearing has a first bearing partner, a second bearing partner and an air cushion separating the first and second bearing partners from each other. The first bearing partner can be a die or a hold-down device. The second bearing partner is a packaging material.

[0015] Another aspect of the invention also relates to a molding apparatus with a packaging material, wherein the die is configured to form a first hydrostatic gas bearing between the die and the packaging material and / or the hold-down device is configured to form a second hydrostatic gas bearing between the hold-down device and the packaging material.

[0016] The die and the pressure device cooperate to support and hold the packaging material, in particular to fix the packaging material during forming. In principle, the packaging material is preferably supported in a contactless and therefore frictionless manner by hydrostatic gas bearings. In a preferred embodiment, a respective aerostatic bearing is formed between the die and the packaging material and between the pressure device and the packaging material. The die, also called a choke bushing, has at least one recess. The at least one recess can be configured as a through opening or can be trough-shaped, i.e. have a bottom. The die can have a flange surrounding the at least one recess, which flange interacts with the pressure device to hold the packaging material in the holding area. The first bearing surface preferably completely surrounds the at least one recess and is arranged parallel to the packaging material in the holding area. For example, the flange forms the first bearing surface. The die can have a radius between the first bearing surface and the at least one recess, in particular at the transition between them.

[0017] The pressure holding device, also called blank holder, preferably completely surrounds the punch. The pressure holding device and the die are preferably movable relative to each other in a stroke direction parallel to the movement direction of the punch. The second bearing surface is preferably arranged parallel to the first bearing surface. The second bearing surface preferably completely surrounds the punch and at least partially or completely coincides with the first bearing surface.

[0018] In the holding area, the packaging material is consequently received between the first and second bearing surfaces, and in the holding area, the hold down device and die exert a holding force on the packaging material to reduce or prevent wrinkling of the packaging material during forming.

[0019] The punch is provided for shaping the packaging material, in particular for deep drawing. The punch is preferably movable with a movement direction oriented substantially perpendicular to the undeformed packaging material or to the first and second bearing surfaces. In this case, the free end of the punch engages the packaging material and draws it into at least one recess of the die. The free end of the punch and / or the at least one recess of the die thus preferably have the shape of the cup to be formed.

[0020] The at least one cup is generally a recess or cavity in the packaging material and is configured to receive the at least one product. The size and shape of the at least one cup can be selected as desired, particularly taking into account the size and shape of the at least one product, and is not limited to a particular size and shape.

[0021] At least one first opening allows a fluid, in particular air, to pass between the first bearing surface and the packaging material to form a (first) hydrostatic gas bearing. This forms a first air cushion or a first air film between the first bearing surface and the packaging material, reducing contact and friction between the die and the packaging material. In order to spread the fluid as uniformly as possible on the packaging material and over as large an area as possible, the first bearing surface preferably has a plurality of corresponding first openings.

[0022] The at least one first opening can be formed, for example, by a slot, a hole or a bore. In one embodiment, the first bearing surface preferably has a slot completely surrounding the respective recess or has a number of slots partially surrounding the respective recess. Additionally or alternatively, the first bearing surface can have a number of holes, preferably distributed around the periphery of the respective recess.

[0023] In a particularly preferred embodiment, the die comprises a first bearing part having or surrounding at least one recess and having a first bearing surface. The first bearing part is at least partially formed from a porous material, in particular a sintered material, provided with a plurality of first openings. In this case, preferably at least the region of the first bearing surface is formed from a porous material. The porous material has a plurality of pores and therefore a plurality of first openings, thereby allowing as uniform a distribution of the compressed air as possible and thus forming the (first) hydrostatic gas bearing uniformly.

[0024] At least one second opening allows a fluid, in particular air, to pass between the second bearing surface and the packaging material to form a (second) hydrostatic gas bearing. This forms a second air cushion or a second air film between the second bearing surface and the packaging material, reducing contact and friction between the hold-down device and the packaging material. In order to spread the fluid as uniformly as possible on the packaging material and over as large an area as possible, the second bearing surface preferably has a plurality of corresponding second openings.

[0025] The plurality of first openings and the plurality of second openings may be in fluid communication with the same source of fluid or compressed air.

[0026] The at least one second opening can be formed, for example, by a slot, a hole or a bore. In one embodiment, the second bearing surface preferably has a slot completely surrounding the respective recess or has a number of slots partially surrounding the respective recess. Additionally or alternatively, the second bearing surface can have a number of holes, preferably distributed around the periphery of the respective recess.

[0027] In a particularly preferred embodiment, the hold-down device comprises a second bearing part surrounding the punch and having a second bearing surface. The second bearing part is at least partially formed from a porous material, in particular a sintered material, provided with a plurality of second openings. In this case, preferably at least the region of the second bearing surface is formed from a porous material. The porous material has a plurality of pores and therefore a plurality of second openings, thereby allowing as uniform a distribution of the compressed air as possible and thus forming the (second) hydrostatic gas bearing uniformly.

[0028] In order to be able to locally adapt the holding force acting on the packaging material to the stresses of the packaging material during shaping, the second bearing surface of the hold-down device preferably has a plurality of segments, the fluid supply to at least a first segment of the plurality of segments being adjustable independently of the fluid supply to at least a further segment of the plurality of segments. For example, the fluid supply to at least a first part of the plurality of segments is adjustable independently of the fluid supply to a second part of the plurality of segments. In particular, the fluid supply to each segment of the plurality of segments may be individually adjustable. Particularly preferably, the pressure at which the fluid is supplied is adjustable. Thereby, each segment of the plurality of segments can act or operate with a fluid, for example compressed air, at a pressure, which pressure can be different from the pressure of at least the other segments. The supply of the fluid is effected via a fluid connection from the plurality of second openings to a fluid supply source.

[0029] The division of the second bearing surface into a plurality of segments can be achieved structurally or functionally. A structural division is effective, for example, in that the second bearing part has a plurality of bearing elements, each connected to a fluid source, preferably each bearing element forming a segment of a plurality of segments. A functional division is effective, for example, in that a first part of the second opening is connected to a second fluid source and a second part of the second opening is connected to a further fluid source. Alternatively, the first part and the second part of the second opening can be connected to the same fluid source, and a regulating device, such as a pressure limiting valve, is provided in each case along the fluid connection of the first part and the second part of the second opening to the fluid source. This can also be applied to a plurality of bearing elements.

[0030] For example, a first pressure can be applied to a first segment of the plurality of segments, and a second pressure, preferably different from the first pressure, can be applied to a second segment of the plurality of segments. The second pressure is preferably 2 to 10 times, more preferably 3 to 4 times, the first pressure. In one exemplary embodiment, the first pressure can be between 0.5 bar and 5 bar, preferably between 1 bar and 2 bar, and the second pressure can be between 5 bar and 10 bar, preferably between 6 bar and 8 bar. However, it is also conceivable that the first pressure corresponds to the second pressure.

[0031] In a similar manner, the first bearing surface of the die preferably has a plurality of segments, and therefore all of the features described with respect to the plurality of segments of the second bearing surface can be similarly transferred to the plurality of segments of the first bearing surface.

[0032] As a rule, a first fluid flow, in particular a first air flow, emerges from at least one first opening and is directed onto the packaging material, and a second fluid flow, in particular a second air flow, emerges from at least one second opening and is likewise directed onto the packaging material.

[0033] In a deep drawing process, it may be desirable that more of the packaging material received between the die and the hold-down device can be guided in the direction of the recess during the deep drawing process. Therefore, the at least one first opening and the at least one second opening are preferably configured such that the respective first or second fluid flow emerging therefrom has a flow direction that is at least partially directed in the direction of the recess. That is, the respective flow direction at the outlet from the at least one first or second opening has a directional component perpendicular to the first or second bearing surface in the direction of the recess and a directional component parallel to the first or second bearing surface.

[0034] According to another aspect of the invention, the invention relates to a packaging machine having a forming device as described above. The packaging machine may be, for example, a blister machine, the forming device being configured to form at least one blister cup into a formed film or flat fiber-based packaging material. The packaging machine may further have a filling station for filling at least one cup with one or more products and a closing device for closing the at least one filled cup. The closing device may be configured as a sealing station for sealing a cover material, such as a cover film, to the packaging material.

[0035] According to another aspect of the invention, a method of forming at least one cup into a packaging material with a forming apparatus includes the steps of placing the packaging material between a die and a pressure holding device of the forming apparatus, closing the forming apparatus by relative movement between the die and the pressure holding device, forming a hydrostatic gas bearing between the packaging material and the pressure holding device and / or between the packaging material and the die, and forming the packaging material into at least one recess in the die with a punch of the forming apparatus.

[0036] In this way, the packaging material is aerostatically supported in the forming device, which makes it possible to reduce contact between the packaging material and the die or pressure device during forming, and thus friction. The reduced friction in turn has the advantage that the die or pressure device does not need to be heated for this purpose, which avoids the adverse effects of heating on the packaging material and the forming process. Continuous energy input for heating the die or pressure device is no longer necessary, which is economically and ecologically advantageous. The reduced friction also makes it possible to increase the holding force acting on the packaging material by the die and pressure device, which leads to less wrinkling of the packaging material and improved packaging quality.

[0037] The method is preferably carried out by means of a forming apparatus or a packaging machine as described above, therefore all the features described with respect to the forming apparatus and the packaging machine can be transferred to the method as well and vice versa.

[0038] The steps of the method are preferably carried out in the order shown, so that when the packaging material is correctly positioned between the die and the hold-down device, the forming device is closed. The hydrostatic gas bearing is preferably not formed until the forming device is closed. Once the hydrostatic gas bearing is formed, forming, in particular deep drawing, of the packaging material is performed, thereby forming at least one cup into the packaging material.

[0039] The method may be provided for simultaneously forming multiple cups into the packaging material and may include forming the packaging material into multiple recesses of the die by a punch. Thus, at least one recess of the die has multiple recesses. The forming device may have multiple punches or the punch may have multiple protrusions, each protrusion configured to form the packaging material into a respective recess of the multiple recesses of the die. The holding down device preferably surrounds each recess of the multiple recesses of the die. The method is described below based on one recess and one punch as a representative example, but these features apply equally to embodiments having multiple recesses, multiple punches or protrusions, and corresponding holding down devices.

[0040] After molding, the hydrostatic gas bearings can be released and the mold apparatus opened by relative movement between the die and the hold-down device. The hydrostatic gas bearings are thus present throughout the molding process, but preferably only while the mold apparatus is closed.

[0041] Positioning the packaging material between the die and the hold-down device may include inserting the packaging material into the former, or introducing or passing a web of packaging material through the former.

[0042] Closing the forming device preferably involves moving the pressure device towards the die, in particular in a stroke direction parallel to the direction of movement of the punch during forming, although it is also possible for the die to move towards the pressure device or for the die and pressure device to move towards each other.

[0043] The step of shaping the packaging material preferably includes moving a punch in a direction of travel that can be aligned perpendicular to a substantially flat shape of the undeformed packaging material, engaging the packaging material with a free end of the punch, and drawing the engaged packaging material into at least one recess in the die, thereby shaping the packaging material to form at least one cup.

[0044] During forming, the packaging material is stretched or compressed to different extents, especially in the corner areas and adjacent areas of the cup to be produced. This is because deep drawing generates tensile and compressive stresses in the packaging material. The compressive stresses can lead to the formation of wrinkles in the packaging material, especially in the holding area between the hold-down device and the die. The wrinkles depend, among other things, on the shape of the cup to be formed, in particular the size of the radius and the cup depth. Based on the shape, it is therefore possible to determine the expected wrinkle size.

[0045] Wrinkles can be counteracted by the holding force that the hold-down device and the die exert on the packaging material in the holding area, which corresponds to a normal force on the packaging material, which generates a friction force between the packaging material and the adjacent tools, i.e. the hold-down device and the die.

[0046] The hydrostatic gas bearing preferably provides a holding force for the packaging material, and the resulting frictional forces counteract the tensile forces occurring in the material during the deep drawing process. Depending on the expected wrinkling, it is therefore possible to determine the required frictional force, on the basis of which, in turn, the required holding force for this can be determined.

[0047] Thanks to the low coefficient of friction of hydrostatic gas bearings, the holding force can be significantly increased without exceeding the yield strength of the packaging material, which allows for more complex cup shapes to be formed, especially cups with tight radii or depths.

[0048] The method preferably further includes the steps of: determining a required friction force in the retention area based on a shape of the at least one cup; determining a retention force based on the determined friction force; and forming a hydrostatic gas bearing based on the determined retention force.

[0049] The frictional force caused by the holding force may be greater than the tensile force in order to securely hold the packaging material between the die and the hold-down device in the holding area. However, the frictional force may be less than the tensile force in order to be able to guide more of the packaging material towards the recess during the deep drawing. It is self-evident that the frictional and tensile forces should be configured such that the shaping of the packaging material and the shaping of at least one cup occurs.

[0050] The hydrostatic gas bearings are preferably formed by a fluid, preferably compressed air, passed between the packaging material and the die or between the packaging material and the hold-down device, the pressure of the fluid being preferably adjustable, whereby the holding force exerted on the packaging material can be varied.

[0051] The formation of the hydrostatic gas bearing may include the formation of a first and / or a second hydrostatic gas bearing, as described above in connection with the molding device. In principle, in all embodiments described herein, it is possible for only the first hydrostatic gas bearing or only the second hydrostatic gas bearing to be provided, or for both the first and the second hydrostatic gas bearings to be provided. Unless otherwise stated, all embodiments of hydrostatic gas bearings apply to both the first and the second hydrostatic gas bearings. Conversely, even when an embodiment with a first and a second hydrostatic gas bearing is described, it is always possible to provide only one hydrostatic gas bearing.

[0052] With respect to the first hydrostatic gas bearing, forming the hydrostatic gas bearing includes creating a first fluid cushion between a first bearing surface of the die and the packaging material. Additionally or alternatively, forming the second hydrostatic gas bearing includes creating a second fluid cushion between a second bearing surface of the hold-down device and the packaging material.

[0053] The creation of the first fluid cushion may in turn include supplying fluid between the die and the packaging material via the first bearing surface, in particular through at least one first opening. The creation of the second fluid cushion may in turn include supplying fluid between the hold down device and the packaging material via the second bearing surface, in particular through at least one second opening.

[0054] Where the first bearing surface of the die has a plurality of segments, forming the (first) hydrostatic gas bearing includes discharging fluid at a first pressure in a first segment of the plurality of segments and discharging fluid at a second pressure in a second segment of the plurality of segments, the first pressure and the second pressure being different.

[0055] Where the second bearing surface of the hold-down device has a plurality of segments, forming the (second) hydrostatic gas bearing includes discharging fluid at a first pressure in a first segment of the plurality of segments and discharging fluid at a second pressure in a second segment of the plurality of segments, the first pressure and the second pressure being different.

[0056] The second pressure is preferably 2 to 10 times, and more preferably 3 to 4 times, the first pressure.

[0057] If both the first and second bearing surfaces have multiple segments, the first and second pressures of the first bearing surface may be different from or correspond to the first and second pressures of the second bearing surface, in which case the pressures may be referred to as a first pressure, a second pressure, a third pressure and a fourth pressure.

[0058] To form such a hydrostatic gas bearing by the fluid, a flow of the fluid is directed onto the packaging material. More precisely, forming the first hydrostatic gas bearing may comprise generating at least a first flow of fluid starting from the die or the first bearing surface and directed at least partially along the packaging material in the direction of the recess of the die. Forming the second hydrostatic bearing may comprise generating at least one second flow of fluid starting from the hold-down device or the second bearing surface and directed along the packaging material in the direction of the punch. [Brief description of the drawings]

[0059] [Figure 1] 1 is a cross-sectional view showing one embodiment of a molding device according to the present invention together with a packaging material. [Diagram 2] 1 is a cross-sectional view showing one embodiment of a molding device according to the present invention together with a packaging material. [Diagram 3] FIG. 3 shows details of the forming device according to FIGS. 1 and 2; [Figure 4] FIG. 2 is a plan view of a bearing surface of a pressing device or a die of a forming device. [Diagram 5]FIG. 1 is a perspective view showing a packaging machine. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0060] 1 and 2 each show a cross-sectional view of one embodiment of a forming apparatus 2 according to the present invention, where packaging material 4 is inserted into forming apparatus 2. Packaging material 4 may be provided as a blank or as a web of packaging material extending through forming apparatus 2.

[0061] The forming device 2 is used to form at least one cup 6 in the packaging material 4, for example a forming device for forming blister cups in a forming film. For this purpose, the forming device 2 has a die 8 with at least one recess 10. Furthermore, the forming device 2 has a holding device 12, whereby the holding device 12 and the die 8 receive the packaging material 4 between them in a holding area 14 surrounding the recess 10. As in the illustrated embodiment, the forming device 2 may have a die 8 with multiple recesses 10 for forming multiple cups.

[0062] The packaging material 4 is substantially flat in shape and has an upper part 4a and a lower part 4b. The die 8 has a first bearing surface 16 facing the pressure device 12 and the lower part 4b of the packaging material 4, and is formed, for example, by a flange 17 surrounding the recess 10 of the die 8. At the transition from the first bearing surface 16 to the recess 10, the die 8 has a radius 19 (see FIG. 3). The pressure device 12 has a second bearing surface 18 facing the die 8 and the upper part 4a of the packaging material 4. In the holding area 14, the packaging material 4 is consequently received between the first bearing surface 16 and the second bearing surface 18.

[0063] To introduce the packaging material 4 into the forming apparatus 2 and receive it between the die 8 and the hold-down device 12 in the holding area 14, the die 8 and the hold-down device 12 can move relative to one another in a stroke direction H. The stroke direction H is preferably oriented perpendicular to the upper side 4a of the undeformed packaging material 4 or perpendicular to the first and second bearing surfaces 16, 18.

[0064] To form the packaging material 4 into the recess 10, e.g. for deep drawing, the forming device 2 further comprises a punch 20, which is preferably movable in a movement direction B. The movement direction B is preferably oriented perpendicular to the upper side 4a of the undeformed packaging material or perpendicular to the first and second bearing surfaces 16, 18. The punch 20 has a free end 22, which faces the packaging material 4 and impinges on it to form it.

[0065] The recess 10 can be formed in the die 8 in a trough or cup shape or, as shown, as a through opening. The trough- or cup-shaped recess 10 preferably has a shape corresponding to the cup to be produced, in particular it will form the negative of the cup. Alternatively, for example as shown in FIG. 2, a counter punch 24 may be provided which cooperates with the punch 20 to shape the packaging material 4. For greater clarity, the counter punch 24 is shown in FIG. 2 at a short distance from the packaging material 4. The counter punch 24 has a free end 26 facing the lower side 4b of the packaging material 4.

[0066] In the holding area 14, the die 8 and hold down device 12 exert a holding force on the packaging material 4 to allow forming of the packaging material 4 by the punch 20 and to prevent the formation of wrinkles in the packaging material 4. To accomplish this in conventional forming apparatus, the packaging material is mechanically clamped between the die and hold down device in the holding area.

[0067] In the forming device 2 under consideration, the die 8 and / or the hold-down device 12 are configured to form a hydrostatic gas bearing in the holding area 14, as will be described below with reference to Figure 3. By means of the hydrostatic gas bearing, the packaging material 4 is supported on at least one side during forming substantially without contact and therefore without friction.

[0068] In the embodiment shown, a first hydrostatic gas bearing 28 is formed between the die 8 and the packaging material 4, and a second hydrostatic gas bearing 30 is formed between the hold-down device 12 and the packaging material 4. The first and second hydrostatic gas bearings 28, 30 may be provided and designed independently of one another. In particular, it is also possible that only the first or second hydrostatic gas bearings 28, 30 are provided.

[0069] The first hydrostatic gas bearing 28 may, for example, have a first air cushion between the first bearing surface 16 and the packaging material 4, in particular the lower part 4b of the packaging material 4, which is indicated in Fig. 3 by an arrow between the first bearing surface 16 and the lower part 4b of the packaging material 4. In a corresponding embodiment, the second hydrostatic gas bearing 30 may have a second air cushion between the second bearing surface 18 and the packaging material 4, in particular the upper part 4a of the packaging material 4, which is indicated in Fig. 3 by an arrow between the second bearing surface 18 and the upper part 4a of the packaging material 4.

[0070] The first and second hydrostatic gas bearings 28, 30 or corresponding air cushions are generated by supplying a fluid, in particular compressed air, between the packaging material 4 and the die 8 or the hold-down device 12. In the following, a preferred embodiment is described in which the fluid is formed by air or compressed air. It is self-evident that other fluids, in particular gases, can also be used.

[0071] For the supply of fluid, the first bearing surface 16 of the die 8 has at least one, preferably as shown, a plurality of first openings 32, which are in fluid communication with a first fluid or compressed air source 34. The second bearing surface 18 of the hold-down device 12 has at least one, preferably as shown, a plurality of second openings 36, which are in fluid communication with a second fluid or compressed air source 38. The plurality of first and second openings 32, 36 allows compressed air to pass between the respective bearing surface 16, 18 and the packaging material 4 and to be uniformly distributed. The plurality of first openings 16 and the plurality of second openings 18 can be formed by holes provided in the die 8 or in the hold-down device 12. It is self-evident that in each case it is possible to provide only one first or second opening 32, 36, which preferably completely surrounds the recess 10. Such a first or second opening 32, 36 may, for example, be in the form of a slot in the respective bearing surface 16, 18.

[0072] Alternatively, the illustrated first bearing part 40 of the die 8 surrounding the recess 10 and having the first bearing surface 16 may be formed from a porous material, in particular a sintered material, having a number of holes forming the plurality of first openings 32. Independently, the illustrated second bearing part 42 of the hold-down device 12 surrounding the punch 20 and having the second bearing surface 18 may be formed from a porous material, in particular a sintered material, having a number of holes forming the plurality of second openings 36.

[0073] The first air flow emerging from the plurality of first openings 32 and the second air flow emerging from the plurality of second openings 36 are essentially directed onto the packaging material 4 to form first and second hydrostatic gas bearings 28, 30, respectively. If it is desired that more packaging material 4 be directed into the recess 10 around the radius 19 during forming by the punch 20, the plurality of first and second openings 32, 36 may be configured such that the first and second air flows, respectively, have a flow direction that is at least partially directed towards the recess 10, as shown by the arrows between the packaging material and the die 8 or hold-down device 12 in FIG.

[0074] FIG. 4 shows a plan view of the second bearing surface 18 of the hold-down device 12. The second bearing surface 18 may have a plurality of segments 44a-44h, and preferably the supply of fluid or compressed air to at least a first portion of the plurality of segments 44a-44h may be adjusted independently of the supply of fluid or compressed air to a second portion of the plurality of segments 44a-44h. This allows the pressure acting on the packaging material 4 in each portion of the plurality of segments, and thus the holding force, to be adjusted as required. For example, as shown diagrammatically in FIG. 4, the first segment 44a of the second bearing surface 18 is connected to the second compressed air source 38. The second segment 44b and the third segment 44h adjacent to the first segment 44a are in fluid communication with the third compressed air source 46 and may be adjusted independently of the second compressed air source 38. The second and third segments 44b, 44h may be arranged in corner regions of the hold-down device 12 and the corresponding recesses 10. The first bearing surface 16 of the die 8 preferably has a plurality of segments in a similar manner, so the features described in relation to FIG.

[0075] 5 shows a schematic perspective view of a packaging machine 48. The packaging machine 48 comprises a forming device 2 as described above for forming at least one cup in a packaging material 4. In this case, the packaging material 4 is of a substantially web-like design and is provided on a supply roll 50 and passes through a number of processing stations of the packaging machine 48, which are described in more detail below. However, the packaging material 4 may also be provided as a flat blank, which is inserted into the individual processing stations.

[0076] The packaging machine 48 may further comprise a conditioning device 52. If the packaging material 4 is configured, for example, as a thermoplastic formed film, the conditioning device 52 may be a heating station for heating the packaging material 4. On the other hand, if the packaging material 4 is a fiber-based packaging material, the conditioning device 52 may be configured, for example, for moistening the packaging material 4. The forming device 2 is preferably arranged downstream of the conditioning device 52.

[0077] Furthermore, the packaging machine 48 has a filling device 54 for filling at least one product into the at least one cup formed in the packaging material 4 by the forming device 2. To close the at least one cup filled with the at least one product, the packaging machine 48 has a closing device 56 for applying a cover material (not shown) to the packaging material 4. The closing device 56 may be configured, for example, to glue or seal the cover material to the packaging material 4.

[0078] In particular, when a web-like packaging material 4 is used, it may be desirable to produce individual packages 58 each having at least one filled, closed cup. To this end, the packaging machine 48 optionally comprises a punching device 60, which is configured to punch or cut the individual packages 58 from the packaging material 4, which is preferably already provided with a covering material.

[0079] In a particularly preferred embodiment, the packaging machine is configured as a blister machine for producing blister packs for medical or pharmaceutical products, consumer or cosmetic products, or food or nutritional supplements.

[0080] An exemplary embodiment of the method according to the invention will now be described with reference to FIGS.

[0081] First, as shown in Figure 1, the packaging material 4 is placed between the die 8 and the pressure device 12 of the forming apparatus 2. Preferably, the lower side 4b of the packaging material faces the die 8 and rests on the first bearing surface 16 of the die 8. The upper side 4a of the packaging material 4 thus faces the pressure device 12. The packaging material 4 preferably completely covers the recess 10, i.e. rests on the flange 17 of the die 8 around the entire recess 10.

[0082] Once the packaging material is in place, the forming apparatus 2 is closed by relative movement between the die 8 and the pressure device 12. In Fig. 1, the forming apparatus 2 is shown in a closed state. The forming apparatus 2 is opened and closed by relative movement between the die 8 and the pressure device 12, for example by raising and lowering the pressure device 12 parallel to the stroke direction H.

[0083] When the forming device 2 is closed, the first and second hydrostatic gas bearings 28, 30 illustrated in Fig. 3 can now be formed between the packaging material 4 and the hold-down device 12 or die 8. For this purpose, a fluid is passed between the first and second bearing surfaces 16, 18 and the packaging material 4. It is self-evident that it is advantageous to have only one of the first and second hydrostatic gas bearings 28, 30, and it is not necessary to provide both hydrostatic gas bearings 28, 30. The hydrostatic gas bearings 28, 30 exert a holding force on the packaging material 4 in the holding area 14 surrounding the recess 10.

[0084] The packaging material 4 can then be shaped into the recess 10 of the die 8 by means of a punch 20, as shown in Figure 2. For this purpose, the punch 20 is moved in a movement direction B and engages the packaging material 4 by means of its free end 22. The punch 20 draws the packaging material 4 into the recess 10, thereby forming a cup 6 in the packaging material 4.

[0085] Forces or stresses occurring during the forming of the packaging material 4 may lead to wrinkling (in the case of compressive stresses) or tearing (in the case of tensile stresses), especially in particularly stressed areas of the packaging material 4. This can be countered by a retention force. The method therefore preferably comprises determining an expected tensile force and determining a retention force based on the determined tensile force. The hydrostatic gas bearings 28, 30 may then be formed based on the determined retention force. In particular, the retention force can be adjusted by adjusting the pressure of the compressed air supplied to form the hydrostatic gas bearings 28, 30.

[0086] In order to targetably increase the retention force, particularly in stressed areas of the packaging material 4, it is preferred that at least one of the first and second bearing surfaces 16, 18, and preferably both bearing surfaces 16, 18, have a plurality of segments 44, as shown in Figure 4. The formation of the first or second hydrostatic gas bearing 28, 30 may then comprise discharging compressed air at a first pressure in a first segment 44a of the plurality of segments 44 and discharging compressed air at a second pressure in at least one second segment 44b, 44h of the plurality of segments 44, where the first pressure and the second pressure are different from each other.

Claims

1. A forming device (2) for forming at least one cup (6) into a packaging material (4), comprising: a die (8) having at least one recess (10); a punch (20) configured to shape the packaging material (4) into the at least one recess (10) of the die (8); a pressing device (12) configured together with the die (8) to receive the packaging material (4) between it and the die (8) in a holding area (14) surrounding the at least one recess (10) of the die (8), the die (8) has a first bearing surface (16) facing the hold-down device (12) in the holding area (14), and the hold-down device (12) has a second bearing surface (18) facing the die (8) in the holding area (14); the first bearing surface (16) has at least one first opening (32), the at least one first opening (32) being in fluid communication with a first fluid source (34), and / or the second bearing surface (18) has at least one second opening (36), the at least one second opening (36) being in fluid communication with the first fluid source (34) or a second fluid source (38); The second bearing surface (18) has a plurality of segments (44a-h), and fluid supply to at least a first segment (44a) of the plurality of segments (44a-h) is adjustable independently of fluid supply to at least further segments (44b-h) of the plurality of segments (44a-h).

2. 2. The molding apparatus (2) of claim 1, wherein the first bearing surface (16) has a plurality of first openings (32), the die (8) has a first bearing component (40) surrounding the at least one recess (10) and having the first bearing surface (16), the first bearing component (40) being at least partially formed from a porous material having the plurality of first openings (32).

3. 2. The molding apparatus (2) of claim 1, wherein the second bearing surface (18) has a plurality of second openings (36), and the hold-down device (12) has a second bearing part (42) surrounding the punch (20) and having the second bearing surface (18), the second bearing part (42) being at least partially formed from a porous material having the plurality of second openings (36).

4. 2. The molding apparatus (2) of claim 1, wherein the first bearing surface (16) has a plurality of first openings (32) and / or the second bearing surface (18) has a plurality of second openings (36), the plurality of first and / or second openings (32, 36) being formed by a plurality of holes.

5. The molding device (2) of claim 1, wherein the at least one first opening (32) is configured such that a fluid flow emerging therefrom has a flow direction that is at least partially directed towards the at least one recess (10).

6. The molding device (2) of claim 1, wherein the at least one second opening (36) is configured such that the fluid flow emerging therefrom has a flow direction that is directed at least in part towards the at least one recess (10).

7. A packaging machine comprising a forming device (2) for forming at least one cup (6) in a packaging material (4), a filling device (54) for filling the at least one cup (6) with a product, and a closing device (56) for closing the at least one filled cup (6), The molding device (2) a die (8) having at least one recess (10); a punch (20) configured to shape the packaging material (4) into the at least one recess (10) of the die (8); a pressing device (12) configured together with the die (8) to receive the packaging material (4) between it and the die (8) in a holding area (14) surrounding the at least one recess (10) of the die (8), the die (8) has a first bearing surface (16) facing the hold-down device (12) in the holding area (14), and the hold-down device (12) has a second bearing surface (18) facing the die (8) in the holding area (14); the first bearing surface (16) has at least one first opening (32), the at least one first opening (32) being in fluid communication with a first fluid source (34), and / or the second bearing surface (18) has at least one second opening (36), the at least one second opening (36) being in fluid communication with the first fluid source (34) or a second fluid source (38); The second bearing surface (18) has a plurality of segments (44a-h), and a fluid supply to at least a first segment (44a) of the plurality of segments (44a-h) is adjustable independently of a fluid supply to at least further segments (44b-h) of the plurality of segments (44a-h).

8. A method for forming at least one cup (6) into a packaging material (4) by means of a forming device (2), comprising the steps of: placing the packaging material (4) between the die (8) and the pressing device (12) of the forming device (2); closing the forming device (2) by relative movement between the die (8) and the hold-down device (12); forming hydrostatic gas bearings (28, 30) between the packaging material (4) and the hold-down device (12) and / or between the packaging material (4) and the die (8); forming the packaging material (4) into at least one recess (10) of the die (8) by a punch (20) of the forming device (2); The step of forming the hydrostatic gas bearings (28, 30) comprises: creating a first fluid cushion between a first bearing surface (16) of the die (8) and the packaging material (4), thereby forming a first hydrostatic gas bearing (28); and / or generating a second fluid cushion between a second bearing surface (18) of said hold-down device (12) and said packaging material (4), thereby forming a second hydrostatic gas bearing (30); the first bearing surface (16) of the die (8) and / or the second bearing surface (18) of the hold-down device (12) each have a plurality of segments (44a-h) forming the hydrostatic gas bearings (28, 30); discharging fluid at a first pressure in a first segment (44a) of each of said plurality of segments (44a-h); The method further comprising discharging fluid at a second pressure in each second segment (44b) of the plurality of segments (44a-h), the first pressure and the second pressure being different.

9. Further, determining a frictional force required to minimize wrinkles around the at least one cup (6) based on the shape of the at least one cup (6); determining a retention force based on the determined friction force; forming the hydrostatic gas bearings (28, 30) based on the determined retention force; 9. The method of claim 8, wherein the hydrostatic gas bearings (28, 30) exert a holding force on the packaging material (4).

10. 9. The method of claim 8, wherein generating the first fluid cushion comprises supplying a fluid between the die (8) and the packaging material (4) via the first bearing surface (16).

11. 9. The method of claim 8, wherein generating the second fluid cushion comprises supplying a fluid between the hold-down device (12) and the packaging material (4) via the second bearing surface (18).

12. 9. The method according to claim 8, wherein forming the hydrostatic gas bearing (28, 30) comprises forming at least one fluid flow on the packaging material (4) starting from the die (8) and / or the hold-down device (12) and directed at least partially along the packaging material (4) in the direction of the at least one recess (10) of the die (8).

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