Multi-roller system with material feed at low pressure

Abstract

The present invention relates to a multi-roll system comprising at least two rolls forming at least one first gap between them, which is configured to receive at least one powder material in order to produce at least one film material and / or web material by compacting the powder material within the first gap, wherein at least one first low-pressure area is provided in at least one feed area for the powder material and the first gap, wherein at least one sealing system is provided to seal the first low-pressure area, the sealing system being in contact with at least one surface of at least one of the rolls, wherein a first roll is movable relative to a second roll in order to change the width of the first gap and / or the distance between the first roll and the second rolls.wherein the sealing system is adjustable to at least two different widths of the first gap and / or two distances between the first roller and the second roller.

Description

[0001] The claimed subject matter relates to a multi-roll system comprising at least two rolls forming at least one first gap between them, which is designed to receive at least one powder material in order to produce at least one film material and / or web material by compacting the powder material within the first gap, wherein at least one first low-pressure area is provided in at least one feed area for the powder material and the first gap, wherein at least one sealing system is provided to seal the first low-pressure area, the sealing system being in contact with at least one surface of at least one of the rolls.

[0002] Various multi-roll systems for the production of material films and / or webs have been proposed in the prior art. For example, EP 3 912 206 A2 discloses a system and a method for manufacturing a dry electrode using a multi-roll system.

[0003] In such systems, the material to be processed into a film and / or web, and especially to be compacted, is provided in powder form. Due to the material's consistency, air is trapped between the powder particles, which must escape the material flow before pressing between the system's rollers. At increasing process speeds, the air becomes trapped in the material flow, leading to undesirable irregularities within the material and the resulting film. To avoid such pores, these pores can be pressed out of the produced film, but this requires a separate pressing step after film production. Alternatively, a counter-pressure can be generated, which must be compensated for by the multi-roll system. Both methods increase complexity and prevent higher process speeds, as the air cannot escape quickly enough due to its inertia.

[0004] To avoid such air inclusions, which lead to increased porosity and defects in the produced film / web, it has been proposed to convey the powder material through a low-pressure or vacuum zone before and upon entering the multi-roll system. Such a system is described, for example, in WO 2020 / 007754 A1, which discloses a method and apparatus for producing an electrode material strip.

[0005] However, the described system has the disadvantage that it is not possible to adapt the device to different target thicknesses of the manufactured material film; at the very least, a complex adaptation of the device is required, which leads to undesirable production interruptions and thus to higher costs.

[0006] The object underlying the claimed subject matter is therefore to further develop the known multi-roll systems in order to enable high production speeds and at the same time a simple adaptation of the system to the desired target thicknesses of the produced film.

[0007] This problem is solved by a multi-roll system comprising at least two rolls forming at least one first gap between them, which is designed to receive at least one powder material in order to produce at least one film material and / or web material by compacting the powder material within the first gap, wherein at least one first low-pressure area is provided in at least one feed area for the powder material and the first gap, wherein at least one sealing system is provided to seal the first low-pressure area, wherein the sealing system is in contact with at least one surface of at least one of the rolls, and wherein a first roll is movable relative to a second roll in order to change the width of the first gap and / or the distance between the first roll and the second rolls.wherein the sealing system is adjustable to at least two different widths of the first gap and / or two distances between the first roller and the second roller.

[0008] It is preferred that at least one first roller rotates about a first axis and at least one second roller rotates about a second axis, optionally with the first axis and the second axis being at least partially parallel to each other.

[0009] It is further proposed that the sealing system comprises at least one sealing component, wherein the sealing component seals the first low-pressure area against at least a part of the environment of the multi-roll system, in particular at an end face of the rolls, optionally the first roll and / or the second roll, and / or has at least one sealing surface whose normal vector is parallel to an axial direction of the first axis and / or the second axis.

[0010] Preferred embodiments of the multi-roll system can be characterized in that the sealing component comprises at least one first sealing component with a first sealing surface and at least one second sealing component with a second sealing surface, wherein optionally the first sealing component and the second sealing component are at least partially connected to each other or at least partially formed as a single part.

[0011] Furthermore, it is proposed that the first roller has at least one first counter surface and the second roller has at least one second counter surface, wherein optionally the first counter surface is in contact with the sealing component, optionally the sealing surface, optionally the first counter surface is in contact with the first sealing component, optionally the first sealing surface and / or the second counter surface is in contact with the second sealing component, optionally the second sealing surface.

[0012] For the embodiments described above, it is preferred that the first axis and / or the second axis protrudes at least partially through the sealing component, at least one opening within the sealing component, wherein optionally the first axis protrudes at least partially through the first sealing component, optionally a first opening within the first sealing component, and / or the second axis protrudes at least partially through the second sealing component, optionally a second opening within the second sealing component.

[0013] Additionally, it is proposed that the opening, optionally the first opening and / or the second opening, is at least partially elongated, optionally elliptical, or optionally the first opening is at least partially elongated, optionally elliptical, and the second opening is at least partially circular, or the second opening is at least partially elongated, optionally elliptical, and the first opening is at least partially circular.

[0014] Preferred embodiments may be characterized in that the sealing surface, optionally the first sealing surface and / or the second sealing surface, is at least partially elongated, optionally elliptical, optionally the first opening and the first sealing surface are at least partially elongated, optionally elliptical, and the second opening and the second sealing surface are at least partially circular, or the second opening and the second sealing surface are at least partially elongated, optionally elliptical, and the first opening and the first sealing surface are at least partially circular.

[0015] It is further proposed that the first counter surface and / or the second counter surface comprise at least one counter material, optionally at least one ceramic material, at least one metallic material, at least one plastic material, at least one hardened material, hardened steel, at least one glass material, at least one polymer material, at least one polyetheretherketone material, at least one alloy material, at least one tungsten nitride material and / or at least one tungsten carbide material, and / or the first counter surface comprises at least one coating of at least one part of the first roller, optionally the end surface of the first roller, and / or the second counter surface comprises at least one coating of at least one part of the second roller, optionally the end surface of the second roller, and / or the first counter surface comprises at least one first counter surface element which, optionally rotationally secured, is attached to the first roller.optionally attached to the end face of the first roller, and / or the second counter surface comprises at least one second counter surface element which is optionally secured against rotation and attached to the second roller, optionally to the end face of the second roller.

[0016] Furthermore, it is preferred that the sealing system, optionally the sealing component, comprises at least one retaining element, wherein the retaining element optionally presses / preloads a sealing component means, optionally the sealing surface, against the first counter surface and the second counter surface, wherein the retaining element optionally comprises at least one first retaining element that presses / preloads the first sealing component, optionally the first sealing surface, against the first counter surface, and / or at least one second retaining element that presses / preloads the second sealing component, optionally the second sealing surface, against the second counter surface.

[0017] For the embodiment described above, it is proposed that the first retaining element is movable relative to the second retaining element, optionally in a radial direction of the first axis and / or the second axis and / or a direction perpendicular to the first axis and / or the second axis.

[0018] Additionally, it is proposed that the first retaining element and the second retaining element be guided relative to each other, optionally by at least one tongue and groove connection.

[0019] Furthermore, it is preferred that the first retaining element is fixedly connected to the first axis in a longitudinal direction perpendicular to the first axis and / or that the second retaining element is fixedly connected to the second axis in a longitudinal direction perpendicular to the second axis and / or that the first axis is rotatably mounted within the first retaining element, preferably by at least one first sealing bearing, and / or that the second axis is rotatably mounted within the second retaining element, preferably by at least one second sealing bearing.

[0020] Furthermore, it is proposed that the first bearing element be held by at least one first fastening element relative to and / or within the first retaining element(s) and / or that the second bearing element be held by at least one second fastening element relative to and / or within the second retaining element(s).

[0021] Advantageous embodiments can be characterized in that the sealing component, optionally the sealing surface, in particular the first sealing component and / or the second sealing component, optionally the first sealing surface and / or the second sealing surface, at least partially comprises at least one second material, optionally at least one metal material, at least one plastic material, at least one hardened material, hardened steel, at least one glass material, at least one polymer material, at least one polyetheretherketone material, at least one alloy material, at least one tungsten nitride material and / or at least one tungsten carbide material, in particular in an area that is in contact with the first counter surface and / or the second counter surface.

[0022] Furthermore, it is proposed that the sealing system comprises at least one sealing element, optionally a sliding sealing element, wherein the sealing element seals the first low-pressure area, in particular against at least a part of the environment of the multi-roll system, along a rolling surface of the roll, optionally by at least partial sliding on at least a part of the rolling surface of the roll, and / or has at least one contact surface with at least one of the rolls, in particular a rolling surface that extends parallel to the first axis and / or to the second axis and / or has a normal vector perpendicular to an axial direction of the first axis and / or the second axis.

[0023] For the alternative described above, it is preferred that the sealing element, optionally a sealing element means of the sealing element, is movable in a direction towards the rolling surface of the first roll and / or the second roll and / or perpendicular to the first axis and / or to the second axis and / or that the sealing element, optionally the sealing element means, is pressed against the surface of the first roll and / or the second roll, optionally by at least one preload and / or spring element.

[0024] It is also proposed that the direction of movement of the sealing element, optionally of the sealing element means, and the normal direction of the contact surface of the rolling surface of the first roller and / or the second roller (i) include a first angle, optionally an angle of attack, in a first relative position of the first roller and the second roller, a first relative position of the first axis and the second axis and / or at a first width of the first gap and (ii) include a second angle, optionally an angle of attack, in a second relative position of the first roller and the second roller, a second relative position of the first axis and the second axis and / or at a second width of the first gap, where the first angle and the second angle are different.

[0025] Alternatively or additionally, it is proposed that the sealing element comprises at least two sealing element parts that are movable relative to each other in a direction that runs at least partially parallel to the first axis and / or the second axis.

[0026] Preferred embodiments can be characterized in that the sealing element comprises a first sealing element, optionally a first sliding sealing element, which is in contact, in particular sliding, with the first roller, optionally the rolling surface of the first roller, and at least one second sealing element, optionally a second sliding sealing element, which is in contact, in particular sliding, with the second roller, optionally the rolling surface of the second roller.

[0027] It is also proposed that the system include at least one second low-pressure area, which is located relative to the first low-pressure area and / or the feed area relative to the first roller and / or the second roller and / or relative to the first low-pressure area and / or the feed area relative to the first gap.

[0028] It is also proposed that a first pressure is present within the first low-pressure area and a second pressure is present in the second low-pressure area, optionally with the first pressure and the second pressure being below a pressure in the vicinity of the multi-roll system and / or optionally with the first pressure being lower than the second pressure.

[0029] In a further embodiment, the multi-roll system comprises at least one third roll, with at least one second gap optionally formed. (i) between the first roller and the third roller, (ii) between the second roller and the third roller or (iii) between the third roller and a fourth roller, and / or material leaving the first gap is conveyed through the second gap.

[0030] Finally, a multi-roll system can be characterized by at least one vacuum pump connected to the first low-pressure area and / or the second low-pressure area, optionally including at least one first vacuum pump connected to the first low-pressure area and / or at least one second vacuum pump connected to the second low-pressure area.

[0031] Thus, the claimed subject matter is based on the remarkable insight that a multi-roll system with a low-pressure supply for a powder material can be provided at a gap of the roll system to enable high production speeds without adding trapped air and pores within the produced film, while simultaneously allowing simple and straightforward adjustment of the roll system to the thickness of the film and / or web to be produced by adjusting the roll gap for the lower pressure range without the further need to replace a seal, by making the seal adjustable in both the axial and radial directions of at least one roll.

[0032] In the following description, the width of a gap between two rollers is to be understood as the geometric extent of the gap and / or the distance between the roller surfaces in a direction perpendicular to the rollers' axes of rotation. Optionally, the width of the gap defines a thickness of the produced film and / or web. The length of a gap is to be understood as the geometric extent of the gap parallel to the rollers, in particular to the rollers' axes of rotation. The length of the gap optionally defines the width of the produced film and / or web.

[0033] The use of a sealing component as described above has the effect that the first low-pressure area can be sealed at an end face and / or at the lateral ends of the respective rollers, and the longitudinal sides of the area can be sealed by sealing elements. This allows the first low-pressure area to be limited on the underside by the rollers in such a way that, due to the adaptability of the sealing system, in particular the sealing component and / or the sealing element, the distance between the rollers and / or the width of the first gap can be changed without negatively affecting the pressure within the first low-pressure area.

[0034] By arranging a powder material feed within the first low-pressure region, the powder feed area to the rollers can be maintained at a low pressure, optionally under vacuum, for example at a pressure below 700 mbar, preferably at or below 300 mbar, and even more preferably at or below 10 mbar. By using a non-circular opening within the sealing component, it is possible for the roller to be moved relative to the sealing component without the sealing surface losing contact with the mating surface, but rather remaining in contact with the mating surface around the first or second axis within the region of the first low-pressure region. Outside the first low-pressure region, the contact surface and the mating surface can lose contact without this negatively affecting the reduced pressure within the first low-pressure region.

[0035] The use of different materials as the mating surface and sealing surface, particularly materials with varying wear resistance, allows control over which element can be sacrificed and replaced. For example, a mating surface material with greater wear resistance, and optionally greater hardness, than the sealing surface material—such as a ceramic material as the mating surface and a plastic material for the sealing surface—offers the advantage that wear occurs on the sealing surface, which can be easily replaced compared to the mating surface. Replacing the mating surface would require the complete removal or replacement of the roller. Such a roller replacement would necessitate recalibration, balancing, and similar processes. The sealing surface, on the other hand, can be replaced by replacing the portion of the sealing component separate from the roller.

[0036] The use of the retaining element ensures that any changes and wear of the sealing surface or the mating surface can be compensated for by preloading the sealing surface against the mating surface. Furthermore, the use of separate retaining elements allows movement of the retaining elements relative to each other to compensate for relative movement of the rollers and thus change the width of the first gap.

[0037] The use of a movable sealing element to seal the first low-pressure area against the environment along the rolling surface of the rollers makes it possible to ensure a reliable seal even with varying widths of the first gap, i.e., with different roller spacings – unlike stationary sealing devices. In particular, the use of a sliding sealing element ensures reliable sealing contact between the sealing element and the rolling surface, especially the contact surface. When at least one of the rollers moves perpendicular to the axis and perpendicular to a direction of movement of the sealing element, the sealing element moves to compensate for a change in distance between a fastening element of the sealing element on a support structure on the one hand, and the surface of the roller, optionally the contact surface, on the other, due to the curvature of the rolling surface.This allows a change in the angle of attack of the sealing element on the rolling surface of the roller due to a movement of the roller relative to the sealing element to be compensated for without negatively affecting the sealing properties.

[0038] In a first embodiment, the film and / or web produced by compacting the powder material exits the first gap at atmospheric pressure. To further reduce the effects of the pressure differential between the pressure within the first low-pressure zone and the surrounding environment of the multi-roller system, particularly in the area of ​​the gap, which could lead to turbulence within the powder material in the region of the first gap, the use of a second low-pressure zone is proposed. It is proposed that a second low-pressure zone be formed on the side of the gap opposite the feed zone. The film material / web is conveyed into the surrounding environment by means of at least one third roller. Preferably, the film is conveyed through a second gap formed between the first or second roller on one side and the third roller on the other side.Alternatively, the second gap is formed between the third roller and a further fourth roller.

[0039] Any air entering the second gap comes into contact with the film / web and not with a powder material. This eliminates or at least reduces the effects of powder turbulence in the area of ​​the first gap, especially if the first gap has a maximum width.

[0040] The multi-roll system described can be used for any material that can form a film and / or web from powder, where the powder can be dry, quasi-dry, moist, or the like. One application is, for example, the production of anode or cathode material in the battery industry.

[0041] Further features and advantages of the claimed subject matter will become apparent from the following description of embodiments of the claimed subject matter with reference to the accompanying figures, wherein Fig. 1 shows a schematic cross-sectional view of a first embodiment of a multi-roll system according to the claimed subject matter; Fig. 2 a perspective view of the multi-roll system of Fig. 1 shows; Fig. 3 an exploded view of a sealing component of the multi-roll system of the Fig. 1 and Fig. 2 shows; Fig. 4 a detailed view of A of the Fig. 3 shows; Fig. 5 Another exploded view of the sealing component of the multi-roll system of the Fig. 1 to 4 shows; Fig. 6a, Fig. 6b Detailed views of a sealing element of the multi-roll system of the Fig. Show 1 to 5; Fig. Figure 7 shows a schematic cross-sectional view of a second embodiment of a multi-roll system according to the claimed subject matter with two low-pressure areas; Fig. Figure 8 shows a schematic cross-sectional view of a third embodiment of a multi-roll system according to the claimed subject matter with two low-pressure areas; and Fig. Figure 9 shows a detailed view of a preferred alternative sealing element.

[0042] Fig. Figure 1 shows a schematic cross-sectional view of a first embodiment of a multi-roll system 1 according to the claimed subject matter. The multi-roll system 1 comprises a first roll 3 and a second roll 5. The rolls 3 and 5 form a gap 7 between them. A powder material 9 is fed into the gap 7. In particular, the powder is fed along the entire, or at least nearly the entire, length of the gap 7. The material is compacted into a film and / or a web 11 by the rolls 3 and 5. The material 7 is fed to the rolls 3 and 5 and to the gap 7 by a conveying device 13, which transports the material 7 from a powder material feed 15, in particular an airlock, to the gap 7.

[0043] In the region of rollers 3, 5 and gap 7, a first low-pressure area 17 is provided in each case. As explained below, the low-pressure area 17 is sealed against the environment of the multi-roll system 1, in particular against atmospheric pressure, by a sealing system 19. The low-pressure area 17 is fluidically connected to and / or open to a low-pressure chamber 21, in which, for example, the conveying device 13 is located and into which an outlet of the powder material feed opens. Although the low-pressure area 17 and the low-pressure chamber are shown as separate elements, they can be combined to form a single part. A pressure is generated within the low-pressure chamber 21 and the low-pressure area 17 that is lower than the pressure in the environment of the multi-roll system 1, in particular below atmospheric pressure.For example, the pressure can be below 700 mbar, preferably below 300 mbar, even more preferably below 10 mbar or below 5 mbar down to a vacuum. This lower pressure is generated by a vacuum pump 23, which is connected to the low-pressure chamber 21 and / or the low-pressure area 17.

[0044] The multi-roller system 1 enables the powder material feed area to be maintained under low pressure, even at the side of the gap 7, by means of a sealing system described below. The sealing system enables the low-pressure area 17 to be sealed by providing sealing components that seal the lateral boundaries of the rollers 3, 5, and by providing sealing elements at a boundary with a rolling surface of the rollers 3, 5 on the side of the gap 7 into which the powder material 9 is fed. Thus, the powder material is fed into the gap 7 between the rollers 3, 5 under low pressure before being formed into a film and / or web 11 within the gap 7 by the compaction forces provided by the rollers 3, 5. The web 11 exits the gap 7 at atmospheric pressure.This prevents air from being trapped between the powder particles, which would otherwise become trapped as pores in the fabric. Since air does not need to be squeezed out, higher processing speeds can be achieved because little or no air needs to escape. In general, the porosity and the number of defects in web 11 can be reduced.

[0045] Fig. Figure 2 shows a perspective view of the multi-roll system 1. As in Fig. As shown in Figure 2, the first roller 3 rotates about a first axis 25, while the second roller 5 rotates about a second axis 27. The low-pressure area 17 is surrounded by the sealing system 19, which comprises sealing components 29 and sealing elements 31. The length of the gap 7 is specifically defined as the geometric extent of the gap along the axes of rotation 25, 27 between the sealing components. Fig. Figure 2 shows the opening 33 of the low-pressure area 17 to the low-pressure chamber 21. The boundaries of the low-pressure area 17 with respect to the low-pressure chamber 21 and the opening 33 are formed by the rollers 3 and 5, in particular the rolling surface 35 of the first roller 3 and the rolling surface 37 of the second roller 5. Preferably, the powder material 9 is fed into the gap 7 along its entire length, or at least nearly its entire length. This measure prevents the need for an opening at the ends of the gap 7 near the sealing components 31. Such an opening would create a connection between the environment, in particular atmospheric pressure, on the one hand, and the low-pressure area 17 or the low-pressure chamber 21 on the other, which would lead to pressure equalization and turbulence in the powder material 9 in these areas.

[0046] As explained above, it is essential that the gap 7, in particular its width, is adjustable in order to adapt to the properties of the web 11, especially its thickness, density, and the like. As explained below, the sealing system 19, in particular the sealing component 29 and / or the sealing element 31, is / are designed to be adjustable in order to allow adjustment of the gap 7 without negatively affecting the sealing properties of the sealing system 19.

[0047] Fig. Figure 3 shows an exploded view of a sealing component 29. The sealing component 29 comprises a sealing element 39, which optionally includes a plastic material such as polyetheretherketone (PEEK). Within the sealing element 39, a first sealing surface 41 and a second sealing surface 43 are formed. The first sealing surface 41 is in contact with a first counter surface 45 located on the first roller 3, particularly at its end face, while the second sealing surface 43 is in contact with a second counter surface 47 located on the second roller 5, particularly at its end face. The counter surfaces 45 and 47 can be formed as separate elements connected to the first roller 3 and the second roller 5, respectively, or they can be implemented as a coating on the end face of the roller 3 and the roller 5, respectively. For example, discs can be used as separate elements.Such discs can be permanently attached to the respective rollers 3 and 5 by means of appropriate pressure rings. To prevent leakage on the side of the discs facing the roller end face, appropriate O-rings can be used in this area, i.e., in the area between the disc and the end face.

[0048] The counter surfaces 45, 47 preferably comprise a counter material with an increased hardness compared to the sealing surfaces 41, 43, such as a ceramic material.

[0049] The sealing component 29 further comprises a retaining element 49, which includes a first retaining element 49a and a second retaining element 49b. As in Fig. As shown in Figure 5, the first axis 25 is rotatably mounted in an opening 51a of the retaining element 49a by means of a bearing element 53a, in particular a sealing bearing, while the second axis 27 is rotatably mounted in an opening 51b of the retaining element 49b by means of a bearing element 53b, in particular a sealing bearing. The bearing elements 51a, 51b are connected to the respective retaining elements 49a, 49b by means of fastening elements 55a, 55b.

[0050] To allow relative movement of the rollers 3, 5 for adjusting the width of the gap 7, the retaining elements 49a, 49b are designed as separate parts that are movable relative to each other. In the illustrated embodiment, however, the retaining elements 49a, 49b are guided relative to each other by a tongue-and-groove connection 57, in particular in a direction perpendicular to the axes 25, 27, optionally in a plane that encompasses the axes 25, 27.

[0051] The sealing component 39 is pressed against the mating surfaces 45, 47 by preload elements in the form of spring elements 59 to ensure a sealing contact between the sealing surfaces 41, 43 and the mating surfaces 45, 47. Furthermore, defined guidance of the sealing component 39 is ensured. The retaining elements 49a, 49b can each be connected to corresponding torque supports of the rollers 3, 5.

[0052] In the illustrated embodiment, the first roller 3 is moved relative to the second roller 5 to adjust the width of the gap 7. In other words, the axis 27 remains unchanged in space, while the first axis 25 is displaced in a radial direction R of the axis 25 within space; that is, the roller 5 represents a fixed roller, while the first roller represents a movable roller.

[0053] In this configuration, the counter surface 47 remains in contact with the radially symmetrical sealing surface 43. The sealing surface 41 has an elongated shape, and an opening 61 within the sealing component center 39 is also elongated. This allows movement of the axis 25, optionally a roller journal of the first roller 3, within the opening 61. Furthermore, the counter surface 45 remains in contact with the sealing surface 41 in the region covered by the low-pressure area 17.

[0054] In Fig. 4 is detail A of Fig. Figure 3 shows a horizontal boundary 63 and a vertical boundary of the low-pressure area 17. Fig. Figure 4 shows a first projection 67 of the counter surface 45 onto the sealing surface 41 when the first roller 3 and the axis 25 are in a position corresponding to a first width of the gap 7. A second projection 69 of the counter surface 45 onto the sealing surface 41 corresponds to an embodiment in which the first roller 3 and the axis 25 are in a position corresponding to a second width of the gap 7 that is larger than the first width of the gap 7.

[0055] As in Fig. As shown in Figure 4, the counter surface 45 remains completely on the sealing surface in the area of ​​the low-pressure region 17, thereby ensuring the sealing of the low-pressure region 17 on the side surfaces of the rollers 3, 5 for the different gap widths, i.e. differently closed and / or open roller gaps.

[0056] Outside the low-pressure area, the sealing component 39, in particular the sealing surface, has a tongue element 71. The tongue element 71 ensures that the counter surface 45, if it is sufficiently supported by the sealing surface even outside the low-pressure area 17, does not negatively affect the mobility of the first axis 25.

[0057] In Fig. Figure 5 shows the elements of the sealing system 17, in particular the sealing component 31, in an exploded view from a different perspective than in the Fig. 3 and Fig. 4 shown.

[0058] In the Fig. 6a and Fig. Figure 6b shows detailed views of the sealing element 31. As can be seen from the Fig. 6a and Fig. As can be seen in Figure 6b, the sealing element 31 comprises a sealing element means 73. The sealing element means 73 is designed as a sliding sealing element. It is movable in one direction D and is in contact with the rolling surface 35 of the first roller 3. Although the first roller 3 is shown, the sealing element 31 is designed accordingly for the second roller 5.

[0059] The sealing element 73 is in contact with the rolling surface 35 in the area of ​​a contact surface 75, which extends particularly parallel to the first axis 25. The sealing element 73 is pre-tensioned against the rolling surface 35 by spring elements 77. In the event of movement of the first roller 3 to adjust the gap 7, the distance between the stationary support 79 and the contact surface 75 increases or decreases due to the curvature of the rolling surface 35. This change in distance is compensated for by the movement of the sealing element 73, thereby ensuring uniform contact of the sealing element 31 with the rolling surface 35 and thus a constant sealing quality.

[0060] In Fig. Figure 7 shows a second embodiment of a multi-roll system 101 according to the claimed subject matter. The elements of the multi-roll system 101, which correspond to the elements of the multi-roll system 1, have the same reference numerals, but increased by 100.

[0061] The multi-roll system 101 is used particularly in configurations where turbulence within the powder material is more likely. This can be due to the powder material itself, for example, its weight or particle size, to comparatively larger gaps 107 used to produce comparatively thicker material webs 111, or simply to the desire to further increase the ability to prevent air inclusions within the material web 111. In particular, when larger gaps 107 are present, the atmospheric pressure acting on the gap 7 in the multi-roll system 1 exerts an increased force on the system 1, especially on the gap 7 and the powder material 9. This can result in air flow through the gap 7 into the low-pressure area 17 or the low-pressure chamber 21. This can lead to turbulence within the powder material 9, resulting in pores or irregularities in the web 11.

[0062] These effects are avoided in the multi-roll system 101. By adding a second low-pressure area 181 in the region of the second, optionally fixed roll 105 and an optionally loose third roll 183, it is possible to achieve a pressure on the side of the gap 107 opposite the first low-pressure area 117 or the first low-pressure chamber 121 that is lower than the ambient pressure of the multi-roll system 101, and in particular lower than atmospheric pressure. For this purpose, the second low-pressure area 181 is located between the first low-pressure area 117 and the ambient environment. This second low-pressure area 181 is fluidically connected to a second low-pressure chamber 185. A vacuum pump 187 can be used to generate a pressure below ambient pressure, which is in particular higher than the pressure within the first low-pressure area 117 or the low-pressure chamber 121.However, the same pressure can also exist in the first low-pressure chamber 121 and the second low-pressure chamber 185.

[0063] The first low-pressure chamber and the second low-pressure chamber are sealed against each other by the sealing system of the first low-pressure chamber 117 and further sliding sealing elements 189. As the web 111 leaves the gap 107, it is picked up by the roller 183 and guided out of the second low-pressure chamber 181. Optionally, it has a sealing system corresponding to the sealing system 19 to allow relative movement of the second roller 105 and the third roller 183, optionally to adjust the width of a second gap between the second, optionally fixed roller 105 and the optionally loose third roller 183, in particular to adapt the width of the second gap to the width of the first gap formed between the first, optionally loose roller 103 and the second roller 105. Furthermore, a sliding sealing element 191 is used to seal the low-pressure chamber 185 in the area of ​​the third roller 183.

[0064] The multi-roll system 101 has the advantage that the ambient air entering through a gap between the rollers 105 and 183 comes into contact with the formed web 111 and not with the powder material 109. Powder turbulence can be avoided or at least reduced.

[0065] It is understood that further low-pressure areas and chambers can be added in series to cascade down the pressure from the environment to the pressure in the first low-pressure chamber.

[0066] In Fig. Figure 8 shows another embodiment of a multi-roll system 101'. The elements of the multi-roll system 101' that correspond to the elements of the multi-roll system 101 have the same reference numeral, but with an apostrophe. In contrast to the multi-roll system 101, the multi-roll system 101' comprises, in addition to the first, optionally loose roll 103', the second, optionally fixed roll 105', and the optionally loose third roll 183', a fourth, optionally fixed roll 193'. In this embodiment, the second gap is formed between a third roll 183' and the fourth roll 193'. This configuration makes it possible to transport the web 111' along a straight line. Furthermore, additional low-pressure areas and low-pressure chambers can be added in series to the first low-pressure chamber 121' and the second pressure chamber 185', as well as to the first low-pressure area 117' and the second low-pressure area 181'.

[0067] In Fig.Figure 9 shows a detail of a preferred sealing element 31. To compensate for any changes in the length of the rollers 3, 5, particularly due to temperature changes, and to ensure a reliable seal, the sealing element 31 comprises two parts 31a, 31b, which are movable relative to each other in a direction E along the axis of the roller. The two parts 31a, 31b slide relative to each other such that the surfaces of the parts 31a, 31b remain at least partially in contact with each other to ensure a reliable seal. In particular, the parts 31a, 31b interlock or complement each other.

[0068] The features disclosed in the description, claims and figures may be essential for the invention in its various embodiments, individually or in any combination. Reference symbol list 1 Multi-roll system 3 roller 5 roller 7 gaps 9 Powder material 11 lane 13 Conveyor device 15 Powder material feed 17 Low-pressure area 19 Sealing system 21 Low-pressure chamber 23 Vacuum pump 25 axle 27 axle 29 Sealing component 31 Sealing element 33 Opening 35 Rolling surface 37 Rolling surface 39 Sealing component materials 41 Sealing surface 43 Sealing surface 45 Counter surface 47 Opposite surface 49 Retaining element 49a, 49b Retaining element 51a, 51b Opening 53a, 53b Bearing element 55a, 55b Fastening element 57 Tongue and groove joint 59 Spring element 61 Opening 63 horizontal boundary 65 vertical boundary 67 Projection 69 Projection 71 Tongue element 73 Sealing element materials 75 contact area 77 Spring element 79 bracket 101, 101' Multi-roll system 103, 103' roller 105, 105' roller 107, 107' gap 109, 109' Powder material 111, 111' Train 113, 113' Conveyor device 115, 115' Powder material feed 117, 117' Low-pressure area 121, 121' Low-pressure chamber 123, 123' Vacuum pump 181, 181' Low-pressure area 183, 183' roller 185, 185' Low-pressure chamber 187, 187' Vacuum pump 189, 189' Sliding seal element 191, 191' Sliding seal element 193' roller A Detail D, E direction R radial direction QUOTES INCLUDED IN THE DESCRIPTION

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

[0000] EP 3 912 206 A2

[0002] WO 2020 / 007754 A1

[0004]

Claims

[1] Multi-roll system (1, 101) comprising at least two rolls (3, 5, 103, 105) forming at least one first gap (7, 107) between them, which is designed to receive at least one powder material (9, 109) in order to produce at least one film material and / or web material (11, 111) by compacting the powder material (9, 109) within the first gap (7, 107), wherein at least one first low-pressure area (17, 117) is provided in at least one feed area for the powder material (9, 109) and the first gap (7, 107), wherein at least one sealing system (19) is provided to seal the first low-pressure area (17, 117), wherein the sealing system (19) has at least one surface (45, 47, 35, 37) on at least one of the rolls (3, 5, 103, 105) is in contact, characterized by, that a first roller (3, 103) is movable relative to a second roller (5, 105) in order to change a width of the first gap (7, 107) and / or to change a distance between the first roller (3, 103) and the second rollers (5, 105), wherein the sealing system (19) is adjustable to at least two different widths of the first gap (7, 107) and / or two distances between the first roller (3, 103) and the second roller (5, 105). [2] Multi-roll system according to claim 1, wherein at least one first roll (3) rotates about a first axis (25) and at least one second roll (5) rotates about a second axis (27), wherein optionally the first axis (25) and the second axis (27) are at least partially parallel to each other. [3] Multi-roll system according to claim 2, wherein the sealing system (19) comprises at least one sealing component (29), wherein the sealing component (29) seals the first low-pressure area (17) against at least a part of the environment of the multi-roll system (1), in particular at an end face of the rollers (3, 5), optionally the first roller (3) and / or the second roller (5), and / or has at least one sealing surface (41, 43) whose normal vector is parallel to an axial direction of the first axis (25) and / or the second axis (27). [4] Multi-roll system according to claim 3, wherein the sealing component (29) comprises at least a first sealing component with a first sealing surface (41) and at least a second sealing component with a second sealing surface (43), wherein optionally the first sealing component and the second sealing component are at least partially connected to each other or at least partially formed as a single part. [5] Multi-roll system according to claim 3 or 4, wherein the first roll (3) has at least one first counter surface (45) and the second roll (5) has at least one second counter surface (47), wherein optionally the first counter surface (45) is in contact with the sealing component (29), optionally the sealing surface (41, 43), optionally the first counter surface (45) is in contact with the first sealing component, optionally the first sealing surface (41), and / or the second counter surface (47) is in contact with the second sealing component, optionally the second sealing surface (43). [6] Multi-roll system according to one of claims 3 to 5, wherein the first axis (25) and / or the second axis (27) extends at least partially through the sealing component (29), at least one opening (51a, 51b) within the sealing component (29), optionally the first axis (25) extends at least partially through the first sealing component, optionally a first opening (51a) within the first sealing component, and / or the second axis (27) extends at least partially through the second sealing component, optionally a second opening (51b) within the second sealing component. [7] Multi-roll system according to claim 6, wherein the opening (51a), optionally the first opening (51a) and / or the second opening, is at least partially elongated, optionally elliptical, optionally the first opening (51a) is at least partially elongated, optionally elliptical, and the second opening (51b) is at least partially circular, or the second opening is at least partially elongated, optionally elliptical, and the first opening is at least partially circular. [8] Multi-roll system according to any one of claims 3 to 7, wherein the sealing surface, optionally the first sealing surface (41) and / or the second sealing surface, is at least partially elongated, optionally elliptical, optionally the first opening (51a) and the first sealing surface (41) are at least partially elongated, optionally elliptical, and the second opening (51b) and the second sealing surface (43) are at least partially circular, or the second opening and the second sealing surface are at least partially elongated, optionally elliptical, and the first opening and the first sealing surface are at least partially circular. [9] Multi-roll system according to any one of claims 3 to 8, wherein the first counter surface (45) and / or the second counter surface (47) comprises at least one counter material, optionally at least one ceramic material, at least one metal material, at least one plastic material, at least one hardened material, hardened steel, at least one glass material, at least one polymer material, at least one polyetheretherketone material, at least one alloy material, at least one tungsten nitride material and / or at least one tungsten carbide material, and / or the first counter surface (45) comprises at least one coating of at least one part of the first roll (3), optionally the end surface of the first roll (3), and / or the second counter surface (47) comprises at least one coating of at least one part of the second roll (5), optionally the end surface of the second roll (5), and / or the first counter surface comprises at least one first counter surface element which, optionally rotationally secured,attached to the first roller, optionally to the end face of the first roller, and / or the second counter surface comprises at least one second counter surface element, which is optionally secured against rotation and attached to the second roller, optionally to the end face of the second roller. [10] Multi-roll system according to one of the claims, wherein the sealing system (19), optionally the sealing component (29), comprises at least one retaining element (49), wherein the retaining element (49) optionally presses / preloads a sealing component means (39), optionally the sealing surface (41, 43), against the first counter surface (45) and the second counter surface (47), wherein the retaining element optionally comprises at least one first retaining element (49a) that presses / preloads the first sealing component, optionally the first sealing surface (41), against the first counter surface (45), and / or at least one second retaining element (49b) that presses / preloads the second sealing component, optionally the second sealing surface (43), against the second counter surface (47). [11] Multi-roll system according to claim 10, wherein the first retaining element (49a) is movable relative to the second retaining element (49b), optionally in a radial direction (R) of the first axis (25) and / or the second axis (27) and / or a direction perpendicular to the first axis (25) and / or the second axis (27). [12] Multi-roll system according to claim 11, wherein the first retaining element (49a) and the second retaining element (49b) are guided relative to each other, optionally by at least one tongue and groove connection (57). [13] Multi-roll system according to any one of the preceding claims 10 to 12, wherein the first retaining element (49a) is fixedly connected to the first axis (25) in a longitudinal direction perpendicular to the first axis (25) and / or the second retaining element (49b) is fixedly connected to the second axis (27) in a longitudinal direction perpendicular to the second axis (27) and / or the first axis (25) is rotatably mounted within the first retaining element (49a), preferably by at least one first sealing bearing (53a), and / or the second axis (27) is rotatably mounted within the second retaining element (49b), preferably by at least one second sealing bearing (53b). [14] Multi-roll system according to claim 13, wherein the first bearing element (53a) is held by at least one first fastening element (55a) relative to and / or within the first retaining element(s) (49a) and / or the second bearing element (53b) is held by at least one second fastening element (55b) relative to and / or within the second retaining element(s) (49b). [15] Multi-roll system according to any one of the preceding claims 3 to 14, wherein the sealing component (29), optionally the sealing surface, in particular the first sealing component and / or the second sealing component, optionally the first sealing surface (41) and / or the second sealing surface (43), at least partially comprises at least a second material, optionally at least a metal material, at least a plastic material, at least a hardened material, hardened steel, at least a glass material, at least a polymer material, at least a polyetheretherketone material, at least an alloy material, at least a tungsten nitride material and / or at least a tungsten carbide material, in particular in an area that is in contact with the first counter surface (45) and / or the second counter surface (47). [16] Multi-roll system according to one of the preceding claims, wherein the sealing system (19) comprises at least one sealing element (31), optionally a sliding sealing element, wherein the sealing element (31) seals the first low-pressure area (17), in particular against at least a part of the environment of the multi-roll system (1), along a rolling surface (35, 37) of the roll (3, 5), optionally by at least partial sliding on at least a part of the rolling surface (35, 37) of the roll (3, 5), and / or has at least one contact surface (75) with at least one of the rolls (3, 5), in particular a rolling surface (35, 37) which extends parallel to the first axis (25) and / or to the second axis (27) and / or has a normal vector perpendicular to an axial direction of the first axis (25) and / or the second axis (27). [17] Multi-roll system according to claim 16, wherein the sealing element (31), optionally a sealing element means (73) of the sealing element (31), is movable in a direction to the rolling surface (35) of the first roll (3) and / or the second roll (5) and / or perpendicular to the first axis (25) and / or to the second axis (27) and / or the sealing element (31), optionally the sealing element means (73), is pressed against the surface of the first roll (3) and / or the second roll (5), optionally by at least one preload and / or spring element (77). [18] Multi-roll system according to claim 16 or 17, wherein the direction of movement of the sealing element (31), optionally of the sealing element means (73), and the normal direction of the contact surface of the rolling surface (35, 37) of the first roll (3) and / or the second roll (5) (i) include a first angle, optionally an angle of attack, in a first relative position of the first roller (3) and the second roller (5), a first relative position of the first axis (25) and the second axis (27) and / or at a first width of the first gap and (ii) include a second angle, optionally an angle of attack, in a second relative position of the first roller (3) and the second roller (5), a second relative position of the first axis (25) and the second axis (27) and / or at a second width of the first gap (7), wherein the first angle and the second angle are different. [19] Multi-roll system according to one of claims 16 to 18, wherein the sealing element comprises at least two sealing element parts which are movable relative to each other in a direction which is at least partially parallel to the first axis and / or to the second axis. [20] Multi-roll system according to one of claims 16 to 19, wherein the sealing element comprises a first sealing element, optionally a first sliding sealing element, which is in contact, in particular sliding, with the first roll, optionally the rolling surface of the first roll, and at least a second sealing element, optionally a second sliding sealing element, which is in contact, in particular sliding, with the second roll, optionally the rolling surface of the second roll. [21] Multi-roll system according to one of the preceding claims, wherein the system (101) comprises at least one second low-pressure area (181) which is located relative to the first low-pressure area (117) and / or the feed area relative to the first roll (103) and / or to the second roll (105) and / or relative to the first low-pressure area (117) and / or the feed area relative to the first gap (107). [22] Multi-roll system according to claim 21, wherein a first pressure is present within the first low-pressure area (117) and a second pressure is present in the second low-pressure area (181), wherein optionally the first pressure and the second pressure are below a pressure in the vicinity of the multi-roll system and / or wherein optionally the first pressure is lower than the second pressure. [23] Multi-roll system according to claim 21 or 22, wherein the multi-roll system (101) comprises at least one third roll (183), optionally comprising at least one second gap (i) between the first roller and the third roller, (ii) between the second roller (105) and the third roller (183) or (iii) between the third roller (183') and a fourth roller (193') and / or material leaving the first gap (107) is conveyed through the second gap. [24] Multi-roll system according to one of the preceding claims, characterized byat least one vacuum pump (23, 123) connected to the first low-pressure area (17, 117) and / or the second low-pressure area (181), optionally at least one first vacuum pump (23, 123) connected to the first low-pressure area (17, 117) and / or at least one second vacuum pump (183) connected to the second low-pressure area (181).

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