Embossing arrangement for embossing a foil web

Abstract

The invention relates to an embossing arrangement (1) for embossing a foil web (24), comprising a bearing roller (2) which defines an axis of rotation (4), wherein an outer surface (42), in particular circular-cylindrical, of the bearing roller (2) has at least a portion of a gas outlet zone (43), in particular annular, comprising a microporous coating (45), and a sleeve-shaped embossing roller (3) arranged coaxially to the axis of rotation (4), in particular with an annular cross-section, which surrounds the bearing roller (2) in a portion of its area and covers the gas outlet zone (43) at least in a portion of its area, in order to form a bearing gap (79) with the bearing roller (2) for a rotatable gas cushion bearing of the embossing roller (3) about the axis of rotation (4), wherein an outer surface (77) of the embossing roller (3) is provided with an embossing motif (78).

Description

[0001] The invention relates to an embossing arrangement for embossing a film web.

[0002] DE 10 2019 215 768 A1 discloses an embossing device comprising an embossing roller rotatable about its longitudinal axis. The roller has an outer surface provided with an embossed structure, which rolls along the surface of a passing material strand to be embossed during embossing. A plurality of suction openings open onto the outer surface. These suction openings communicate with a vacuum channel system formed in the embossing roller, which is connected to a vacuum source, so that the passing material strand is drawn toward the outer surface. A temperature control system is located in the embossing roller, which enables heating and / or cooling of the outer surface of the embossing roller.

[0003] The object of the invention is to provide an embossing arrangement with which an improved embossing result can be achieved.

[0004] This object is achieved for an embossing arrangement of the type mentioned at the outset in that the embossing arrangement comprises a bearing roller which determines a rotational axis, wherein an outer surface, in particular a circular cylindrical outer surface of the bearing roller has at least in some regions a gas outlet zone, in particular annularly circumferential, which comprises a microporous coating, and in that the embossing arrangement comprises an embossing roller which is arranged coaxially to the rotational axis and is sleeve-shaped, in particular with a circular cross-section, which surrounds the bearing roller in some regions and covers the gas outlet zone at least in some regions in order to form a bearing gap with the bearing roller for a rotatable gas cushion bearing of the embossing roller about the rotational axis, wherein an outer surface of the embossing roller is provided with an embossed motif.

[0005] The bearing roller and the embossing roller thus form an assembly that can be mounted on a machine frame or machine stand to provide a foil web with an embossing at least in part. The foil web wraps around the embossing roller at least in part, so that the outer surface of the embossing roller, which is provided with at least one embossed motif, can be brought into direct contact with the foil web.

[0006] For example, it can be provided that the film web extends from a film roll mounted on the machine frame in a first spatial direction and comes into tangential contact with the outer surface of the embossing roller. Furthermore, it can be provided that the film web extends from the embossing roller in a second spatial direction and can be wound onto a film drum. In this case, the wrap angle at which the film web wraps around the embossing roller in sections is determined by an angle between the first spatial direction and the second spatial direction.

[0007] It is preferably provided that the film web between the film roll and the film drum rests against the embossing roller with a predeterminable mechanical tension in order to experience a three-dimensional structuring through contact with the at least one embossed motif formed on the outer surface of the embossing roller.

[0008] To carry out the embossing process, it is advantageous if the embossing roller exerts as little braking force as possible, preferably no braking force at all, on the film web. This avoids the film web being subjected to additional tensile forces along its transport direction between the film roll and the film drum that exceed the tensile forces required to unwind the film web from the film roll and wind it onto the film drum. For this reason, it is advantageous if the embossing roller can be mounted with at least virtually no friction, which is ensured by a gas-cushioned bearing between the embossing roller and the bearing roller.

[0009] For this purpose, at least one gas outlet zone is formed on the bearing roller, which determines the rotational axis for the embossing roller, through which compressed air can be introduced into a bearing gap formed between the outer surface of the bearing roller and an inner surface of the embossing roller. It is preferably provided that the bearing roller has a circular-cylindrical outer surface, wherein in this case the rotational axis corresponds to a rotational symmetry axis for the bearing roller. It is preferably provided that the embossing roller has a circular-cylindrical inner surface, the inner diameter of which is adapted to an outer diameter of the outer surface of the bearing roller in such a way that an annular bearing gap can form between the bearing roller and the embossing roller. The bearing gap is preferably located in an interval between 0.002 mm and 1 mm, in particular in an interval between 0.005 mm and 0.3 mm.

[0010] To ensure the advantageous supply of compressed air into the bearing gap, the gas outlet zone of the bearing roller is designed as a recess in the outer surface of the bearing roller, which is filled with a microporous coating. This microporous coating is preferably formed from a stainless material, in particular a metal material, which fills the recess in the outer surface of the bearing roller. For example, the microporous coating can be produced by a sintering process or a foaming process. It has proven advantageous if the pores of the microporous material have an average diameter of 5 µm to 50 µm, preferably an average diameter of 10 µm to 30 µm.

[0011] The gas outlet zone can extend over a partial area of ​​the outer surface of the bearing roller and can be designed, in particular, as a circular ring section or as a circular ring aligned coaxially with the rotational axis. It is preferably provided that several gas outlet zones are provided on the bearing roller. It is particularly preferably provided that one gas outlet zone or a part of the several gas outlet zones is arranged directly adjacent to a wrap-around area determined by the contact of the film web with the embossing roller, in order to ensure the most advantageous support of the embossing roller relative to the bearing roller.

[0012] The embossing roller is preferably adapted to the bearing roller in such a way that the bearing roller covers all gas outlet zones (either the single gas outlet zone or the multiple gas outlet zones) in order to ensure the most efficient use of the compressed air provided to the gas outlet zone(s).

[0013] In order to ensure advantageous attachment of the bearing roller to a machine frame or machine stand, it is assumed that the bearing roller has a greater extension than the embossing roller in the direction of the rotation axis.

[0014] The at least one embossed motif provided on the outer surface of the embossing roller can be incorporated directly into the outer surface of the embossing roller, for example, by material removal processes, such as milling or erosion, and / or material deposition processes, such as deposition welding or laser sintering. Alternatively, the at least one embossed motif can be fixed as a replaceable element on the outer surface of the embossing roller.

[0015] Advantageous further developments of the invention are the subject of the subclaims.

[0016] It is expedient if the gas outlet zone comprises a recess formed in the outer surface of the bearing roller, which is fluidically connected to a compressed air duct extending along the rotational axis, in particular opening out at an axial end face of the bearing roller, and which is filled with the microporous coating, wherein the microporous coating is formed flush with regions of the outer surface of the bearing roller that border the gas outlet zone. For example, it is provided that, to produce the gas outlet zone, a recess is first formed in the outer surface of the bearing roller, preferably made of a metal material, in particular steel, using a machining process, in particular milling or erosion.This recess can be introduced into the outer surface of the bearing roller as a slot, hole, or pocket-like depression and is then filled with the microporous coating, particularly through a sintering or metal foaming process, up to the outer surface. Care must be taken to ensure that the compressed air channel leading into the recess is not blocked by the microporous coating. The compressed air channel extends along the rotational axis, preferably to an axially aligned end face of the bearing roller, and thus enables compressed air to be supplied to the gas outlet zone. The microporous coating of the gas outlet zone is configured such that it does not protrude beyond an envelope geometry of the outer surface of the bearing roller, particularly a circular cylinder shell.

[0017] It is preferably provided that a first mouth recess is formed on the outer surface of the bearing roller, which is connected to a supply channel extending along the axis of rotation in the bearing roller, in particular opening out at an axial end face of the bearing roller, and that a second mouth recess is formed on an inner surface of the embossing roller, which is connected to a supply bore extending in the direction of an outer surface of the embossing roller, wherein the first mouth recess and the second mouth recess are arranged, in particular opposite one another, in a common mouth recess plane oriented transversely to the axis of rotation.The purpose of the first orifice recess and the second orifice recess is to conduct a fluid flow across the bearing gap between the bearing roller and the embossing roller, wherein the flow direction for the fluid flow depends on the pressure conditions at the first orifice recess and the second orifice recess. For example, an overpressure can be provided at the first orifice recess to effect a fluid flow from the bearing roller to the embossing roller. Alternatively, a negative pressure can be provided at the first orifice recess to effect a fluid flow from the embossing roller to the bearing roller. The first orifice recess is connected to a supply channel formed in the bearing roller and can be used, for example, to connect to a fluid source, in particular a compressed air pump, or to a fluid sink, in particular a vacuum pump.The second orifice recess is fluidically connected to a supply bore that extends radially outward toward the outer surface of the embossing roller and opens there. To ensure advantageous transmission of the fluid flow across the bearing gap between the bearing roller and the embossing roller, the first orifice recess and the second orifice recess are arranged in a common orifice recess plane.

[0018] For example, it can be provided that the first orifice recess extends over the entire circumference of the outer surface of the bearing roller, and that the second orifice recess extends over the entire circumference of the inner surface of the embossing roller, so that the fluid flow can always be passed on, regardless of the rotational position of the embossing roller relative to the bearing roller. In this case, the first orifice recess and the second orifice recess can each be introduced as grooves in the outer surface of the bearing roller and in the inner surface of the embossing roller, respectively, running coaxially to the rotational axis.

[0019] Alternatively, it can be provided that the first mouth recess extends only over a partial region of the circumference of the outer surface of the bearing surface and that the second mouth recess extends over a partial region of the inner surface of the embossing roller in order to achieve a dependence for the forwarding of the fluid flow on a rotational position of the embossing roller relative to the bearing roller. For this purpose, the first mouth recess can be designed, for example, as a radial bore or as a first groove that extends at least partially in a circumferential direction. Furthermore, the second mouth recess can be designed as a radial bore or as a second groove that extends at least partially in a circumferential direction.

[0020] In a further embodiment of the invention, a gas exchange region is formed on the outer surface of the embossing roller, said gas exchange region comprising a depression made in the outer surface, in particular covered with a microporous coating, wherein the depression is fluidically connected to the supply bore. The gas exchange region enables the local provision of overpressure or underpressure. As a result, the film web, which wraps around the embossing roller at least in regions, can be locally lifted from the outer surface of the embossing roller when overpressure is applied to the gas exchange region, or can be locally sucked onto the outer surface of the embossing roller when underpressure is applied to the gas exchange region. The gas exchange region is preferably designed in the same way as the at least one gas outlet zone formed on the bearing roller.The fluidically communicating connection of the gas exchange area with the supply bore ensures the fluidic connection of the gas exchange area to the second orifice recess as well as the first orifice recess and the supply channel connected to the first orifice recess.

[0021] It is advantageous if the gas exchange area extends in the circumferential direction of the embossing roller in the shape of a circular ring or in the shape of a circular ring section.

[0022] It is expedient if the gas exchange area is provided with the embossed motif that is at least partially raised and / or at least partially recessed in the radial direction. This allows the embossed motif to be transferred particularly efficiently to the film web, provided that a negative pressure is applied to the gas exchange area, which can achieve a local increase in the forces acting on the film web in the radial direction inward toward the rotation axis.

[0023] In a further embodiment of the invention, it is provided that the bearing roller is mounted in a stationary manner, in particular in a rotationally fixed manner, on a machine frame and / or that a drive device for initiating a rotational movement relative to the bearing roller is assigned to the embossing roller. It is particularly advantageous if the bearing roller can be aligned in its spatial orientation relative to the machine frame and if, for this purpose, an adjustment device is formed between the machine frame and the bearing roller. With this adjustment device, for example, a spatial orientation of the rotation axis can be adjusted relative to a central axis of a film roll, which is also fixed to the machine frame, and / or relative to a central axis of a film drum, which is also fixed to the machine frame. The drive device can be designed to convert fluidic or electrical drive energy into a rotational movement of the embossing roller.For example, a hydraulically, pneumatically, or electrically driven gear motor is mounted on the machine frame, which enables a rotational movement to be initiated on the embossing roller via a chain, V-belt, or toothed belt. Alternatively, the drive device is located between the bearing roller serving as the stator and the embossing roller serving as the rotor. This can optionally convert pneumatic energy into an air motor or electrical energy into a synchronous or asynchronous motor. The drive device can optionally be configured to accelerate or decelerate the rotational movement of the embossing roller.

[0024] Instead of the drive device, a braking device can also be installed between the machine frame and the embossing roller or between the bearing roller and the embossing roller to apply a defined braking torque from the embossing roller to the film web. For example, the bearing roller and the embossing roller form a pneumatic air brake or an electric eddy current brake.

[0025] In an advantageous development of the invention, it is provided that at least one fluid channel is formed in the bearing roller, which extends between an inlet opening and an outlet opening, wherein the inlet opening and the outlet opening are arranged on an axial end face of the bearing roller. The fluid channel serves, for example, to control the temperature of the bearing roller and for this purpose is flowed through by a fluid, preferably water or air, which has a temperature difference compared to the environment of the embossing arrangement. For example, it is provided that heated air flows through the fluid channel in order to heat the bearing roller and the embossing roller which surrounds the bearing roller at least in regions. It is advantageous if the inlet opening and the outlet opening are arranged on the same axial end face of the bearing roller.Alternatively, it can also be provided that the inlet opening is arranged on a first axial end face of the bearing roller and the outlet opening is arranged on a second end face opposite the first end face. The fluid channel preferably extends along the rotational axis and particularly preferably at least almost over the entire length of the bearing roller.

[0026] Preferably, the fluid channel comprises a first helical fluid channel section extending coaxially to the axis of rotation and a second helical fluid channel section extending coaxially to the axis of rotation, which second helical fluid channel section is offset from the first helical fluid channel section by a predeterminable angle, in particular by 180 degrees, with respect to the axis of rotation. Due to the helical configuration of the first fluid channel section and the second fluid channel section, the fluid in the fluid channel can flow through almost the entire volume of the embossing roller. Due to the angular offset between the first fluid channel section and the second fluid channel section, the two fluid channel sections are intertwined, so that when a fluid that is heated or cooled relative to the ambient temperature is provided, uniform temperature control of the bearing roller and thus also of the embossing roller can be ensured.

[0027] It is expedient if a first orifice is formed on the outer surface of the bearing roller, which is connected to the fluid channel, and a second orifice is formed on an inner surface of the embossing roller, which is connected to a fluid recess extending in the embossing roller, wherein the first orifice and the second orifice are arranged, in particular opposite one another, in a common orifice plane oriented transversely to the rotational axis. This enables a transfer of fluid from the fluid channel of the bearing roller into the fluid recess of the embossing roller, for example, to enable locally different temperature control of a region of the embossing roller using the fluid.

[0028] Preferably, a third orifice is formed on the outer surface of the embossing roller, which is connected to the fluid recess. Through this third orifice, fluid supplied to the embossing roller via the fluid channel of the bearing roller and the opposing first and second orifices can be discharged at the outer surface of the embossing roller into the environment or onto the film web partially wrapping around the embossing roller, for example, to enable targeted local temperature control of the film web.

[0029] In an advantageous development of the invention, a discharge opening is formed on the outer surface of the bearing roller, which is connected to the fluid channel and is arranged in the plane of the discharge recess. The discharge opening allows fluid, which is provided via the fluid channel, to be discharged into the bearing gap without the fluid necessarily having to flow into the second discharge opening of the embossing roller.

[0030] Preferably, the first mouth recess and the mouth opening are formed in the mouth recess plane in adjacent circular ring segments of the outer surface of the bearing roller, and the second mouth recess has an extension in a circumferential direction of the inner surface of the embossing roller that is smaller than a distance between the first mouth recess and the mouth opening in a circumferential direction of the outer surface of the bearing roller. With this arrangement of the mouth opening, it can be provided, for example, that the gas exchange region is preheated by the heated fluid provided via the fluid channel of the bearing roller during a rotation phase of the embossing roller relative to the bearing roller, in which no film web is in contact with the respective gas exchange region, provided that the mouth opening is arranged opposite the second mouth recess.As soon as the gas exchange area enters a rotation phase in which the film web is in contact with the gas exchange area, a negative pressure can be applied to the second mouth recess via the first mouth recess, for example, in order to suck the film web into the preheated gas exchange area, which is of particular interest if the embossing motif of the embossing roller is also arranged at the gas exchange area.

[0031] An advantageous embodiment of the invention is illustrated in the drawing. Fig. 1 a strictly schematic representation of an embossing arrangement, with a machine frame, a foil roll, a bearing roller with embossing roller and a foil drum, Fig. 2 a strictly schematic sectional view of the bearing roller and the embossing roller, Fig. 3 a strictly schematic sectional view of the bearing roller and the embossing roller, and Fig. 4 a strictly schematic partial sectional view of the bearing roller and the embossing roller.

[0032] The representations of the Fig. 1 to 4 are not to be regarded as technical drawings, but merely as schematic representations, so that structures shown in the individual figures are not necessarily shown in the other figures in exactly the same representation, dimensions or orientation.

[0033] One in the Fig. The embossing arrangement 1 shown in Figure 1 comprises a purely exemplary plate-shaped machine frame 21 to which a bearing roller 2, a film roll 22, and a film drum 23 are attached. Purely by way of example, the film roll 22 is rotatably mounted on the machine frame 21 and provided with a braking device (not shown in detail) in order to ensure a predetermined resistance to unwinding of a film web 24 wound onto the film roll 22. The bearing roller 2 is mounted in a stationary and, in particular, rotationally fixed manner on the machine frame 21 and is surrounded at least in part by an embossing roller 3, which is described in more detail below. The embossing roller 3 is mounted on the bearing roller 2 for rotation about a rotation axis 4, as will be explained in more detail below.

[0034] Furthermore, a film drum 23 is arranged on the machine frame 21, which is designed for a winding movement for the film web. For example, the film drum 23 is provided with a drive device (not shown) to enable a rotational movement to be initiated on the film drum 23.

[0035] As the representation of the Fig. 1 can be removed, the film web 24 extends from the film roll 22 in the spatial direction 26 towards the embossing roller 3. The film web 24 comes into contact with the embossing roller 3 in a tangential direction and wraps around the embossing roller 3 with a wrap angle 25. Starting from the embossing roller 3, the film web 24 extends in the spatial direction 27 towards the film drum 23.

[0036] The embossing roller 3 is provided on an outer surface 77 purely by way of example with an embossed motif 78 which is repeatedly arranged at a constant angular pitch and which projects in the radial direction from the outer surface 77 of the embossing roller 3 and is embossed into the film web 24 during the rolling movement of the embossing roller 3 of the film web 24, as shown schematically in the Fig. 1. If necessary, a counterpressure roller (not shown here) can be arranged below the embossing roller 3 in order to increase the embossing effect for the embossed motifs 68. For reasons of clarity, the three-dimensional structuring of the film web 24 is shown only in the area of ​​the embossing roller 3 and for the transport path up to the film drum 23.

[0037] On an end face 47 of the bearing roller 2, purely by way of example, several compressed air connections 48 are arranged on a common diameter (not shown) and at the same angular pitch. These connections are intended for connection to a compressed air source (not shown) and are designed to supply compressed air into a bearing gap 69, described in more detail below, between an outer surface 42 of the bearing roller 2 and an inner surface 76 of the embossing roller 3. Furthermore, two vacuum connections 49 as well as an inlet opening 36 and an outlet opening 37 of a fluid channel, described in more detail below, are arranged on the end face 47.

[0038] From the sectional view of the Fig. 2 shows that the bearing roller 2 has a tubular outer shell 50, which is provided with a first bearing journal 53 at a first end region 51 and with a second bearing journal 54 at a second end region 52. Extending inside the outer shell 50 between the first bearing journal 53 and the second bearing journal is an inner tube 55, which is provided on an outer surface 56 with a first helix 57 projecting in the radial direction and with a second helix 58. The first helix 57 and the second helix 58 are arranged in the manner of a double-start thread. The outer surface 56 of the inner tube 55, together with the first coil 57 and an inner surface 59 of the outer shell 50, defines a first fluid channel section 38. Furthermore, the outer surface 56 of the inner tube, together with the second coil 57 and the inner surface 59 of the outer shell 50, defines a second fluid channel section 39.

[0039] By way of example, it is provided that the second bearing pin 54 is penetrated by a longitudinal bore 62 which is arranged coaxially to the axis of rotation 4. A sealing ring 63 is received in the longitudinal bore 62 and is provided for radially sealing a connecting pipe 64 which is partially inserted into the longitudinal bore 62. A first transverse bore 65 and a second transverse bore 66 extend from the longitudinal bore 62. The first transverse bore 65 is fluidically connected to the first fluid channel section 38 in a manner not shown in detail. The second transverse bore 66 is fluidically connected to the second fluid channel section 39 in a manner not shown in detail.

[0040] Thus, for example, heated air can be supplied to the first transverse bore 65 via the connecting pipe 64 serving as inlet opening 36, in order to flow from there through the first helical fluid channel section 38 up to just before the first bearing pin 53. In the area of ​​the first bearing pin 53, the first fluid channel section 38 merges, in a manner not shown in detail, into the second, likewise helical fluid channel section 39, which guides the fluid up to the second transverse bore 66, from where it can be discharged through an annular gap 67, which is delimited by the longitudinal bore 62 and the connecting pipe 64 and which serves as the outlet opening 37.

[0041] The outer shell 50 of the bearing roller 2 is provided with recesses 44, which are formed in particular in the shape of a pocket, starting from an outer surface 42. These recesses are each filled with a microporous coating 45. This microporous coating 45 is designed such that it is flush with the remaining, preferably circular outer surface 42 of the bearing roller 2. Starting from the Fig. From the compressed air connections 48 shown in Figure 1 on the end face 47 of the bearing roller 2, compressed air channels 46 extend parallel to the rotational axis 4, which can, for example, be angled outward at right angles in the radial direction at the ends to ensure a fluidly communicating connection with the respective microporous coating 45. This creates, purely by way of example, circular gas outlet zones 43 on the outer surface 42 of the bearing roller 2. The compressed air exiting through these gas outlet zones 45 flows into the bearing gap 79 between the bearing roller 2 and the embossing roller 3, thereby enabling a virtually frictionless and self-centering gas cushion bearing of the embossing roller 3 relative to the bearing roller 2.

[0042] Furthermore, a supply channel 33 is formed in the outer shell 50, which also extends from the end face 47 and is angled outward at a right angle in the radial direction at its end, forming a first opening recess 31 on the outer surface 42 of the bearing roller 2. For example, the supply channel 33 extends from one of the vacuum connections 49 arranged on the end face 47.

[0043] Opposite the first mouth recess 31, a second mouth recess 74 is formed on the inner surface 76 of the embossing roller 3. The first mouth recess 31 and the second mouth recess 74 are arranged in a Fig. 2, so that an overpressure or underpressure provided at the first mouth recess 31 can be directly transmitted to the oppositely arranged second mouth recess 74. Extending radially outward from the second mouth recess 74 is a supply bore 80 which opens into a microporous coating 73 in a depression 72 of a gas exchange region 71 of the embossing roller 3. Purely by way of example, the gas exchange region 71 is designed in the same way as the gas outlet zone 43 of the bearing roller 2 and differs only in that an embossed motif 78 is provided which is raised radially outwardly above the outer surface 77 of the embossing roller 3 and is intended to be used for the three-dimensional structuring of the film web 24.

[0044] In the Fig. 3, the above-described construction for the bearing roller 2 and the embossing roller 3 is shown from a different angle and with different sections. Fig. 3 shows in detail that the first transverse bore 65 is fluidically connected to the first fluid channel section 38 and that the second transverse bore 66 is fluidically connected to the second fluid channel section 39. Furthermore, Fig. 3 shows the helical design of the two fluid channel sections 38, 39. The flow direction for a fluid flowing through the fluid channel 35 resulting from the arrangement of the two fluid channel sections 38, 39 offset by 180 degrees relative to the rotation axis 4 is symbolized by the directional arrows 68, 69 in the two fluid channel sections 38, 39.

[0045] In the Fig. 4 shows a detail view of the outer shell 50 and the bearing roller, from which the arrangement of the gas outlet zone 43 on the bearing roller 2 and the gas exchange area 71 on the embossing roller is shown in more detail. For reasons of clarity, Fig. 4 no hatching is provided.

[0046] The bearing roller 2 is penetrated by compressed air channels 46 aligned parallel to the rotation axis 4, which open at the ends at the compressed air connections 48. As can be seen from the sectional view of the Fig. 4, radial bores 70 extend outwards from the compressed air channel 46 shown in section, extending into the recess 44 and thus ensuring the fluidic communication between the compressed air bore 46 and the microporous coating 45. As can be seen from the Fig. 1, the compressed air connections 48 are arranged at regular angular pitches over the circumference of the bearing roller 2, so that a compressed air supply to the gas outlet zones 43 is also ensured over the entire circumference of the bearing roller 2. The compressed air flowing from the gas outlet zones 43 into the bearing gap 79 ensures the air bearing for the embossing roller 3.

[0047] Furthermore, the supply channels 33 extending from the vacuum connections 49 extend parallel to the compressed air channels 46, of which in the illustration the Fig. 4 only one is shown in dashed lines, which is in a manner not shown in detail in fluidic communication with the Fig. 4 visible first mouth recesses 31. The first mouth recesses 31 are each designed as circular segment-like circumferential grooves, thus do not extend over the entire circumference of the outer surface 42 of the bearing roller 2. By way of example, it is provided that two of the Fig. 4 extend only in the region of the wrap angle 25, while the third of the first mouth recesses 31 extends slightly beyond the wrap angle 25 purely by way of example. This makes it possible for the gas exchange regions 71 formed on the embossing roller 3 to be supplied with the negative pressure provided at the vacuum connections 49 only in the region of the wrap angle 25. Purely by way of example, it is further provided that, circumferentially adjacent to the first mouth recesses 31, first mouth openings 40 are formed, each of which is designed as circumferential grooves encircling the circumference in the manner of a segment of a circle and does not extend over the entire circumference of the outer surface 42 of the bearing roller 2. By way of example, it is provided that the first mouth openings 40 extend only away from the wrap angle 25.In this way, it can be achieved that the gas exchange regions 71 formed on the embossing roller 3 away from the wrap angle 25 are supplied with the fluid provided in the fluid channel (not shown), for example a heated fluid.

[0048] Again Fig.4 can still be removed, a supply bore 80 is provided on the inner surface 76 of the embossing roller 3, which extends purely by way of example in the radial direction and extends from the second mouth recess 74 to a transverse channel 81. The transverse channel 81 is aligned purely by way of example parallel to the axis of rotation 4 and extends below the gas exchange region 71 of the embossing roller 3. Starting from the transverse channel 81, a plurality of radial bores 82, each aligned in parallel, extend radially outwards and open into the recess 72 of the gas exchange region 71 of the embossing roller 3 and thus enable a fluid inflow from the outside into the microporous coating 73 or a fluid discharge to the outside from the microporous coating 73.

[0049] Purely by way of example, the embossed motif 78 is formed on the outer surface of the gas exchange region 71. In an embodiment of the embossing roller not shown, the embossed motif is either arranged away from the gas exchange regions or arranged in regions inside and outside the gas exchange regions. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] DE 10 2019 215 768 A1

[0002]

Claims

[1] Embossing arrangement (1) for embossing a film web (24), with a bearing roller (2) which determines a rotational axis (4), wherein an in particular circular-cylindrical outer surface (42) of the bearing roller (2) has at least in some regions a gas outlet zone (43), in particular annularly circumferential, which comprises a microporous coating (45), and with an embossing roller (3) which is arranged coaxially to the rotational axis (4) and is sleeve-shaped, in particular with a circular cross-section, which surrounds the bearing roller (2) in some regions and covers the gas outlet zone (43) at least in some regions in order to form a bearing gap (79) with the bearing roller (2) for a rotatable gas cushion bearing of the embossing roller (3) about the rotational axis (4), wherein an outer surface (77) of the embossing roller (3) is provided with an embossed motif (78). [2] Embossing arrangement (1) according to claim 1, characterized byin that the gas outlet zone (43) comprises a recess (44) made in the outer surface (42) of the bearing roller (2), which recess is fluidically connected to a compressed air channel (46) extending along the axis of rotation (4), in particular opening out at an axial end face (47) of the bearing roller, and which is filled with the microporous coating (45), wherein the microporous coating (45) is formed flush with regions of the outer surface (42) of the bearing roller (2) that border on the gas outlet zone (43). [3] Embossing arrangement (1) according to claim 1 or 2, characterized byin that a first mouth recess (31) is formed on the outer surface (42) of the bearing roller (2), which is connected to a supply channel (33) extending along the axis of rotation (4) in the bearing roller (2), in particular opening out at an axial end face (47) of the bearing roller (2), and in that a second mouth recess (74) is formed on an inner surface (76) of the embossing roller (3), which is connected to a supply bore (80) extending in the direction of an outer surface (77) of the embossing roller (3), wherein the first mouth recess (31) and the second mouth recess (74) are arranged, in particular opposite one another, in a common mouth recess plane (32) oriented transversely to the axis of rotation (4). [4] Embossing arrangement (1) according to claim 3, characterized bythat the first mouth recess (31) is designed as a radial bore or as a first groove which runs at least partially in a circumferential direction and that the second mouth recess (74) is designed as a radial bore or as a second groove which runs at least partially in a circumferential direction. [5] Embossing arrangement (1) according to claim 4, characterized by that a gas exchange region (71) is formed on the outer surface (77) of the embossing roller (3), which gas exchange region comprises a depression (72) introduced into the outer surface (77), in particular covered with a microporous coating (73), wherein the depression (72) is fluidically connected to the supply bore (80). [6] Embossing arrangement (1) according to claim 5, characterized by that the gas exchange region (71) extends in the circumferential direction of the embossing roller (3) in the shape of a circular ring or in the shape of a circular ring section. [7] Embossing arrangement (1) according to claim 5, characterized bythat the gas exchange region (71) is provided with the embossed motif (78) which is at least partially raised and / or at least partially recessed in the radial direction. [8] Embossing arrangement (1) according to one of the preceding claims, characterized by that the bearing roller (2) is mounted in a stationary, in particular rotationally fixed, manner on a machine frame (21) and / or that the embossing roller (3) is assigned a drive device for initiating a rotational relative movement with respect to the bearing roller (2). [9] Embossing arrangement (1) according to one of the preceding claims, characterized by that at least one fluid channel (35) is formed in the bearing roller (2), which extends between an inlet opening (36) and an outlet opening (37), wherein the inlet opening (36) and the outlet opening (37) are arranged on an axial end face (47) of the bearing roller (2). [10] Embossing arrangement (1) according to claim 9, characterized byin that the fluid channel (35) has a first helical fluid channel section (38) running coaxially to the axis of rotation (4) and a second helical fluid channel section (39) running coaxially to the axis of rotation (4), which second helical fluid channel section is arranged offset from the first helical fluid channel section (38) by a predeterminable angle, in particular by 180 degrees, with respect to the axis of rotation (4). [11] Embossing arrangement (1) according to claim 9 or 10, characterized bythat a first mouth opening is formed on the outer surface (42) of the bearing roller ()2, which is connected to the fluid channel (35), and that a second mouth opening is formed on an inner surface of the embossing roller (3), which is connected to a fluid recess extending in the embossing roller (3), wherein the first mouth opening (40) and the second mouth opening are arranged, in particular opposite one another, in a common mouth opening plane oriented transversely to the axis of rotation (4). [12] Embossing arrangement (1) according to claim 11, characterized by that a third mouth opening is formed on the outer surface (77) of the embossing roller (3), which is connected to the fluid recess. [13] Embossing arrangement (1) according to one of claims 3 to 7 in conjunction with one of claims 9 or 10, characterized bythat an orifice opening is formed on the outer surface (42) of the bearing roller (2), which is connected to the fluid channel (35) and which is arranged in the orifice recess plane (32). [14] Embossing arrangement (1) according to claim 13, characterized by that the first mouth recess and the mouth opening in the mouth recess plane (32) are formed in adjacent circular ring segments of the outer surface (42) of the bearing roller (2) and that the second mouth recess has an extension in a circumferential direction of the inner surface (76) of the embossing roller (3) which is smaller than a distance between the first mouth recess and the mouth opening in a circumferential direction of the outer surface (42) of the bearing roller (2).

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