Apparatus and method for cleaning of crimping rollers

Abstract

The invention relates to a crimping station for an apparatus for manufacturing aerosol-generating articles. The crimping station comprises at least one crimping roller (10, 12) and a laser cleaning system (20) configured to direct a laser beam (22) onto a surface of the crimping roller. The invention further relates to an apparatus for manufacturing aerosol-generating articles. The invention further relates to a method for cleaning a crimping roller.

Description

[0001] APPARATUS AND METHOD FOR CLEANING OF CRIMPING ROLLERS

[0002] The present disclosure relates to a crimping station and an apparatus for manufacturing aerosol-generating articles. The present disclosure further relates to a method for cleaning a crimping roller.

[0003] It is known to produce and process crimped sheets of material in the production of aerosol-generating articles. For example, a crimped sheet of homogenized tobacco material may be used as an aerosol-forming substrate in an aerosol-generating article. For example, a crimped sheet of a paper-based material may be used in an aerosol-generating article.

[0004] Typically, the band or sheet of material is passed between a pair of crimping rollers to obtain the crimped sheet. The crimping rollers may be formed by a pair of interleaved rollers able to impair crimp corrugations to a sheet or band of material passing between these two rollers. It may happen that residues of the crimped sheet, for example organic material, remain stuck on the surface of the crimping rollers. This may negatively affect the crimping process. Therefore, it may be advantageous to include means for cleaning the crimping rollers.

[0005] On-line cleaning of the crimping rollers may be difficult due to their corrugated surfaces and high operational speed.

[0006] It would be desirable to provide an apparatus and method for effectively cleaning of crimping rollers. It would be desirable to provide an apparatus and method for cleaning of crimping rollers at high speed. It would be desirable to provide an apparatus and method for cleaning of crimping rollers without damaging the crimping rollers. It would be desirable to provide an apparatus and method for cleaning of crimping rollers without excessively heating up the crimping rollers.

[0007] According to an embodiment of the invention there is provided a crimping station for an apparatus for manufacturing aerosol-generating articles. The crimping station may comprise at least one crimping roller. The crimping station may comprise a laser cleaning system configured to direct a laser beam onto a surface of the crimping roller.

[0008] According to an embodiment of the invention there is provided a crimping station for an apparatus for manufacturing aerosol-generating articles. The crimping station comprises at least one crimping roller. The crimping station comprises a laser cleaning system configured to direct a laser beam onto a surface of the crimping roller.

[0009] An apparatus and method for effectively cleaning of crimping rollers may be provided. An apparatus and method for cleaning of crimping rollers at high speed may be provided. An apparatus and method for cleaning of crimping rollers without damaging the crimping rollers may be provided. An apparatus and method for cleaning of crimping rollers without excessively heating up the crimping rollers may be provided. The laser cleaning system may be configured to vary the direction of the laser beam. The laser cleaning system may be configured to vary the direction of the laser beam to allow selectively guiding the laser beam onto different areas on the surface of the crimping roller. The laser cleaning system may be configured to vary the direction of the laser beam in a direction parallel to a rotational axis of the crimping roller. A direction parallel to a rotational axis of the crimping roller may also be denoted as a direction along the width of the surface of the crimping roller, or as a transversal direction on the surface of the crimping roller. The laser cleaning system may be configured to vary the direction of the laser beam in a direction perpendicular to the rotational axis of the crimping roller. The laser cleaning system may be configured to vary the direction of the laser beam in both directions parallel and perpendicular to the rotational axis of the crimping roller. The laser cleaning system may be configured to allow setting different patterns of the laser beam on the surface of the crimping roller.

[0010] The laser cleaning system may comprise a motion system able to move the at least one laser beam to cover at least the transversal surface of the crimping roller. The motion system may be configured to move the laser source back and forth along a direction parallel to a rotational axis of the crimping roller over the width of the crimping roller. The laser cleaning system may comprise a control system able to manage the motion system and at least one laser source (e.g., to active it or stop it).

[0011] The laser cleaning system may be configured to guide the laser beam onto the surface of the crimping roller in an approximately perpendicular direction. The laser cleaning system may be configured to guide the laser beam onto the surface of the crimping roller in a perpendicular direction. The laser cleaning system may be configured to guide the laser beam onto the surface of the crimping roller at an angle of between 75 degrees and 105 degrees, preferably between 80 degrees and 100 degrees, more preferably between 85 degrees and 95 degrees, with respect to a tangent to the surface of the crimping roller. The tangent may be a tangent that contacts the surface of the crimping roller at the point of impingement of the laser beam onto the surface of the crimping roller.

[0012] The laser cleaning system may be configured to provide a continuous laser beam onto the surface of the crimping roller. The laser cleaning system may be configured to guide the laser beam onto the entire the surface of the crimping roller.

[0013] The laser cleaning system may be configured to selectively guide the laser beam onto top parts of ridges on the surface of the crimping roller.

[0014] The target areas for the laser beam may be the waste areas which are on the top of the ridges of the underlying crimping roller corrugated surface. The top of the ridges may be areas which have strongly pressed on the band of material passing between the crimping rollers, and so may be the areas where, in case of waste remaining on the crimping rollers, the waste could strongly be stuck on the corrugated surface. By targeting and vaporizing waste portion in these areas with the laser beam, the waste may lose most of its attachment to the crimping roller surface.

[0015] Furthermore, the waste substrate on the ridges may be thinner in comparison to other parts of the waste on the crimping rollers, so the vaporizations of the substrate portions in these areas may be easier and more efficient.

[0016] Guiding the laser beam onto top parts of ridges on the surface of the crimping roller may be advantageous because thickness of a waste portion on a top ridge area might be correctly estimated by the difference between the expected distance to the top of the ridge (which is known) and the current distance to the top of the waste, allowing to determine the laser power and duration of activation needed to vaporize such waste portion without reaching the metal. Such accurate determination might be more difficult for a waste portion which is in a groove as the exact quantity of waste is not, in such case, necessarily the difference between the expected distance to the bottom of the groove and the current distance to the top of the waste, as there could be an empty volume between the waste and the bottom of the groove.

[0017] The crimping roller may rotate at between about 80 to 380 rpm for a diameter of about between 25 to 40 cm. The laser cleaning system may be configured such that the laser beam moving transversally reported to the surface of the crimping roller follows in fact a diagonal path on the surface of the roller. The slope of the diagonal is related to the relative transversal speed of the laser beam reported to the circumferential speed of the roller. To proceed to a transversal path on the surface of the roller, the laser cleaning system may be configured to adequately correct the laser beam trajectory.

[0018] The surface of the crimping roller may be corrugated. The corrugation may comprise ridges. The ridges may be spaced about every 1 millimeter, having about 0.5 millimeter in width. A depth between the top of the ridges and the bottom of the grooves may be about 1 millimeter. The ridges may be aligned with the direction of the moving band of material, creating a longitudinal corrugation pattern. However, more complex patterns can also be used.

[0019] Generally, a crimping roller may be described as a cylindrical element in form of a circular right cylinder configured to rotate around its cylindrical axis. As used herein, the term surface of a crimping roller may refer to the lateral surface of such cylindrical element. As used herein, the top portions of the ridges may be the radially outermost surfaces of the crimping roller, i.e. the surfaces of furthest distance from the rotation axis.

[0020] The surface of the crimping roller may be a metal surface. A width of the surface may be 125 millimeters or below. A length of the surface may be between 39 centimeters and 62 centimeters.

[0021] The crimping station may comprise an air jet cleaning system. The air jet cleaning system may be configured to direct a stream of compressed air onto the surface of the crimping roller. The air jet cleaning system may create an upward force lifting waste portions from the surface of the crimping roller.

[0022] By the combination of the laser cleaning system and the air jet cleaning system, the cleaning efficiency may be improved. The on-line cleaning efficiency at the high rotational speed of the crimping roller may be improved.

[0023] By the contribution of the air jet cleaning system, the energy of the laser beam may be reduced in comparison to a system without the additional the air jet cleaning system. Heating up of the roller surface may be reduced due to the reduced laser energy.

[0024] The stream of compressed air may cool down the surface of the crimping roller. This may help to prevent any heat from the laser beam to spread into the roller.

[0025] Risk of heat-deforming of the crimping roller may be reduced. This may be particularly advantageous for crimping rollers with finely intertwined corrugations. Also, excessive warming up of a crimping roller may be undesired because the roller may thereby inadvertently heat the band of material. Particularly, where the band of material comprises volatile compounds such as an aerosol-forming substrate, excessive warming up of the band of material may lead to undesired volatilization of material. The combination of the laser cleaning system and the air jet cleaning system may thus be particularly advantageous when crimping sheets of aerosolforming material. By the combination of the laser cleaning system and the air jet cleaning system, a cleaning process for crimping rollers that can have the quality of the laser cleaning (non-contact, relative high speed, low damage to the roller surface) while able to cope with the specificities of the crimping rollers and lowering the indicated risks of thermal degradation of one or both of the crimping roller surface and the band of material.

[0026] By the combination of the laser cleaning system and the air jet cleaning system, the laser beam may be used to vaporize only key parts of a waste portion, for instance the parts on the ridges which are thin (so easier to vaporize with a laser beam) and most probably strongly stuck to the corrugated surface. Then, once the waste main attachments to the crimping roller are vaporized or weakened by the laser, the remaining waste may be attacked by tangential compressed air jets which can target areas where such compressed air jets could be very efficient to pull the waste off the surface, for instance just ahead of the waste portion so that the air jets create a kind of upward force lifting the waste from the surface due to the air jets tangential direction and the cylindrical shape of the roller. Then all loose debris may be suck into the vacuum system.

[0027] Thanks to the complementary work between these systems, the laser beam does not have to be used on all the waste, but can be used to vaporize a minimum quantity of waste and during a minimum of time, limiting at most the risk that the laser heats the metal of the crimping roller, even if high powered laser is used, while still having an overall apparatus and method presenting a high cleaning efficiency. For example, layers of waste material stuck on the corrugation surfaces of crimping rollers may present strong variations of thicknesses, from quite thin on top of the ridges to thicker when into the grooves, making it difficult for a laser beam to vaporize the substrate without hitting the underlying crimping roller surface. The air jet cleaning system may assist.

[0028] The air jet cleaning system may be configured to vary the direction of the stream of compressed air. The air jet cleaning system may be configured to vary the direction of the stream of compressed air to allow selectively guiding the stream of compressed air onto different areas on the surface of the crimping roller. The air jet cleaning system may be configured to vary the direction of the stream of compressed air in a direction parallel to a rotational axis of the crimping roller.

[0029] The air jet cleaning system may be configured to guide the stream of compressed air onto the surface of the crimping roller in an approximately tangential direction. The air jet cleaning system may be configured to guide the stream of compressed air onto the surface of the crimping roller in a tangential direction. The air jet cleaning system may be configured to guide the stream of compressed air onto the surface of the crimping roller at an angle of 15 degrees or less, preferably 10 degrees or less, more preferably 5 degrees or less, with respect to a tangent to the surface of the crimping roller. The tangent may be a tangent that contacts the surface of the crimping roller at the point of impingement of the stream of compressed air onto the surface of the crimping roller.

[0030] The air jet cleaning system may be positioned with respect to a rotational direction of the crimping roller such that the stream of compressed air and the surface of the crimping roller move towards each other in an area where the stream of compressed air contacts the surface of the crimping roller. An air jet cleaning system able to direct a stream of compressed air in the opposite direction than the rotation of the crimping roller, at targeted areas may particularly efficiently blow away remaining particles or residues trapped within corrugations of the surface of the crimping roller. An air jet cleaning system able to direct a stream of compressed air, somehow tangential to the roller’s surface and in the opposite direction than the rotation of the crimping roller, at targeted areas may particularly efficiently blow away remaining particles or residues trapped within corrugations of the surface of the crimping roller.

[0031] The stream of compressed air may be somehow tangential to the curvature of the crimping roller, in opposition to the direction of rotation of the crimping roller and contacting the surface of the crimping roller in front of the waste.

[0032] The air jet cleaning system may benefit of a “grooves effect” of the corrugated surface of the crimping roller, as the grooves mechanically channel the stream of compressed air, increasing their forces, and creating an upward force that could pull away the waste from the corrugated surface. The air jet cleaning system may be configured to provide a plurality of streams of compressed air onto the surface of the crimping roller. The air jet cleaning system may be configured to guide the streams of compressed air of the plurality of streams of compressed air onto the surface of the crimping roller at different angles.

[0033] By the different angles, there may be several streams of compressed air with different inclinations, ones used to unstick and lift up a waste portion from the roller surface, and following ones to build pressure under the lifted waste portion and tear it from other waste portions still attached to the surface, so that the unstuck portion can get lose and be drawn into the vacuum system.

[0034] The air jet cleaning system may be configured to provide a constant stream of compressed air onto the surface of the crimping roller.

[0035] The air jet cleaning system may be configured to create a constant transversal line of compressed air just downstream of the laser cleaning area.

[0036] The air jet cleaning system may be configured such that one or more streams of compressed air are directed to bounce on the crimping roller surface, just in front of a waste portion. Thereby the stream of air may go under the waste portion and lift it.

[0037] The crimping station may be configured such that an area on the surface of the crimping roller is first cleaned by the laser cleaning system and afterwards cleaned by the air jet cleaning system. The laser cleaning system may be arranged upstream of the air jet cleaning system with respect to a rotational direction of the crimping roller.

[0038] The crimping station may comprise a detection system. The detection system may be configured to detect waste material located on the surface of the crimping roller.

[0039] The detection system may identify the areas of the crimping roller’s surface with waste on them and may define accordingly the targets for the laser cleaning system and the air jet cleaning system. The detection system may decrease the size of the areas to hit with the laser to reduce the risk of heat transmission to the roller surface and to be able to proceed to effective laser vaporizations in the short timespan allowed due to the rotation of the crimping roller, while keeping a high cleaning efficiency.

[0040] The detection system may be configured as an image capture detection system. The image capture detection system may comprise a camera.

[0041] Differences in color between waste material, for example organic waste, and the color of the surfaces of the crimping rollers, for example metal color of metal roller surfaces, may be utilized by the image capture system. Optionally, specific colored lights may be used to increase a color contrast. Optionally, angled lights may be used to increase a silhouette image of a corrugated surface expected from a clean (i.e. , without waste) crimping roller surface to help the detection of waste localizations. The detection system may comprise an infra-red sensor for detecting the waste material on the surface of the crimping roller based on a temperature difference between the waste material and the crimping roller.

[0042] The detection system may comprise a distance sensor for detecting the waste material on the surface of the crimping roller based on a measured distance between the distance sensor and the crimping roller. With an expected corrugation profile of the crimping roller being known, the differences between the detected distance versus the expected distance may indicate an undesirable waste on the roller. For example, a laser sensor may be used as a distance sensor. Laser distance sensors may have a quick response and high accuracy, typically finer than 1 millimeter.

[0043] The detection system may be configured to locate a position of the waste material on the surface of the crimping roller. The detection system may be configured to locate a position of the waste material the surface of the crimping roller and, based on the position, identify a target area on the surface of the crimping roller for the laser cleaning system.

[0044] The laser cleaning system may be configured to adjust one or both of a power of the laser beam and an exposure time of the laser beam based on information received from the detection system.

[0045] The detection system may screen the crimping roller surface ahead of the laser beam, to capture where are the roller’s areas covered with organic waste. “Ahead” means upstream of the laser beam with respect to a rotational direction of the crimping roller. The exact positions of the ridges of the crimping roller may be recorded in advance in the systems controlling the laser. Thereby, the laser beam may then target the waste portions which are on the top ridges’ areas even if said ridges are not visible because of waste covering them.

[0046] The detection system may comprise a first detection subsystem for detecting waste material located the surface of the crimping roller before being cleaned by the laser cleaning system. The detection system may comprise a second detection subsystem for detecting waste material located the surface of the crimping roller before being cleaned by the air jet cleaning system. The detection system may comprise a third detection subsystem for detecting waste material located the surface of the crimping roller after being cleaned by the air jet cleaning system. The first detection subsystem may be located upstream of the laser cleaning system with respect to a rotational direction of the crimping roller. The second detection subsystem may be located downstream of the laser cleaning system and upstream of the air jet cleaning system with respect to a rotational direction of the crimping roller. The third detection subsystem may be located downstream of the air jet cleaning system with respect to a rotational direction of the crimping roller. Screening the crimping roller surface after the laser beam and before the air jets may be advantageous to detect where are the roller’s areas still covered with waste material after the laser cleaning to specifically target those areas with the air jet cleaning system.

[0047] Screening the crimping roller surface after the air jet cleaning system may be advantageous to detect where are potentially roller areas still covered with waste to verify the efficiency of the waste removal process and to record where waste could be found at the next turn of the roller and / or to mark the part of the crimped material that could have received, due to the remaining waste, an improper crimping.

[0048] The air jet cleaning system may be configured to adjust one or both of a power of the stream of compressed air and an exposure time of the stream of compressed air based on information received from the detection system.

[0049] The laser beam may have a wavelength of between 200 nanometers and 500 nanometers, or between 700 nanometers and 1300 nanometers, or between 7 micrometers and 13 micrometers.

[0050] The laser cleaning system may comprise one or more of a CO2 laser, an UV laser, and a fiber laser. The laser cleaning system may comprise more than one laser, for example two lasers. The laser cleaning system may comprise a CO2 laser and an UV laser. The CO2 laser may be located upstream or downstream of the UV laser with respect to a rotational direction of the crimping roller.

[0051] A CO2 laser may be particularly advantageous. A usual wavelength of a CO2 laser, for example 10.6 micrometers, may be well-absorbed by organic material and may be mostly reflected by most metals and so may create limited heating of metal roller surface.

[0052] A UV laser may be particularly advantageous. A UV laser may induce photochemical reactions that break the molecular bonds of the surface of the contaminants with minimal thermal input to the underlying metal roller surface, reducing the need for significant heating, thus minimizing the risk of thermal damage. UV lasers normally have a much smaller wavelength (typically around 355 nm) than CO2 laser, and so are less reflected by metal. Still a UV laser may heat precise spots in the targeted zone by means of a precise beam.

[0053] A fiber laser may offer a good balance between power and precision.

[0054] The laser cleaning system may include a combination of different kinds of lasers, for instance CO2 to clean large areas and then UV for residues or small wastes which could have resisted the CO2 laser.

[0055] For example, after the crimping roller surface has left the crimped material, a first system including a CO2 laser may make a first cleaning stage. Then, before the crimping roller surface contacts again the sheet of material to be crimped, a second system including a UV laser and a CO2 laser makes a second cleaning stage, using either the CO2 laser in case large areas of waste remain on the roller or the UV laser in case there are only small waste areas.

[0056] Using a laser beam to clean the crimping roller may be particularly advantageous where the surface of the crimping roller is a metal surface. Using a laser beam to clean the crimping roller may be particularly advantageous where the surface of the crimping roller is a metal surface and the waste to be removed is organic waste material. The laser beam may at least partly vaporize the waste material.

[0057] The laser cleaning system may comprise a pulsed laser.

[0058] A pulsed laser which concentrates the beam power on very short peak bursts may allow to vaporize unwanted substrate in such a short duration that only the substrate bears the majority of the heating effect and that there is minimal heat transfer to the underlying crimping roller, for example a metal surface of the crimping roller.

[0059] An average power of the laser may be between about 100 W and 600 W, preferably about 300 W. The frequency may be between about 1 MHz and 5 MHz, preferably about 2 MHz. A spot diameter of the laser may be between about 100 pm and 800 pm, preferably between 300 pm and 400 pm. A pulse duration may be between about 100 picoseconds to 500 nanoseconds, preferably between 20 nanoseconds to 500 nanoseconds.

[0060] The laser cleaning system may comprise a laser operating in continuous wave (CW) mode.

[0061] The trajectory of the laser beam may be corrected by the laser cleaning system according to the rotational speed of the crimping roller. Thereby, a transversal trajectory of the laser beam reported to the surface of the crimping roller may be provided.

[0062] The laser cleaning system may be configured such that the laser beam may make more than one transversal pass. Thereby, the laser may space the beam activation on targeted areas. For example, hitting one out of two in a first pass, then the other ones in a second and last pass. This may allow the surface of the crimping roller to cool between two close hits.

[0063] The band of material may be a sheet of aerosol-forming substrate. The sheet of aerosol-forming substrate may comprise a tobacco compound. The tobacco material may be Tobacco Cast Leaf. The sheet of aerosol-forming substrate may comprise a paper like substrate containing nicotine.

[0064] The sheet of aerosol-forming substrate may be a fiber-based substrate. For instance, the sheet of aerosol-forming substrate may be made from a cellulose mixture and said mixture may comprise: fibers, a binder and an aerosol-forming agent. The fibers may be cellulose fibers. The binder may comprise a derivative of cellulose, for instance carboxymethylcellulose and hydroxypropylmethylcellulose. The aerosol-forming agent may be a polyhydric alcohol, for instance triethylene glycol or 1 ,3-butanediol or glycerine. The sheet of aerosol-forming substrate may be made from a tobacco-free cellulose mixture. An amount of the fibers in the mixture may be 15.0 percent to 20.0 percent on dry weight basis. An amount of the binder in the mixture may be 28.0 percent to 30.0 percent on dry weight basis. An amount of the aerosol-forming agent in the mixture may be 45.0 percent to 55.0 percent on dry weight basis. For instance, an amount of the carboxymethylcellulose in the mixture may be 5.0 percent to 6.0 percent on dry weight basis. For instance, an amount of the hydroxypropylmethylcellulose in the mixture may be 21.0 percent to 24.0 percent on dry weight basis. The mixture may also comprise nicotine and fumaric acid. An amount of the nicotine in the mixture may be 1.0 percent to 2.0 percent on dry weight basis. An amount of the fumaric acid in the mixture may be 1.5 percent to 2.0 percent on dry weight basis.

[0065] According to some embodiments, the sheet of aerosol-forming substrate has an elongation at break in longitudinal direction between 5.0 mm and 7.5 mm, optionally between 5.5 mm and 7.0 mm. The sheet of aerosol-forming substrate may have an elongation at break in cross direction between 9.5 mm and 12.5 mm, optionally between 10.0 mm and 12.0 mm.

[0066] The sheet of aerosol-forming substrate may have a Young’s module in cross direction between 0.8 N / mm and 1.2 N / mm, optionally between 0.9 N / mm and 1.1 N / mm. The sheet of aerosol-forming substrate may have a Young’s module in longitudinal direction between 5 N / mm and 7 N / mm, optionally between 5.5 N / mm and 6.5 N / mm.

[0067] The sheet of aerosol-forming substrate may have a thickness (t) between 0.15 mm and 0.25 mm. The sheet of aerosol-forming substrate may have a grammage between 100 g / m2and 160 g / m2. The sheet of aerosol-forming substrate may have a humidity between 5 percent and 10 percent. The sheet of aerosol-forming substrate may have a stickiness between 0.0150 N and 0.0165 N. The sheet of aerosol-forming substrate may have a width (A) between 80 mm and 250 mm.

[0068] According to other embodiments, the sheet of aerosol-forming substrate may be a cast leaf, such as tobacco cast leaf. The cast leaf may be obtained through a casting process from ingredients such as tobacco powder or other nicotine containing materials, water, fibers, for instance cellulose, glycerin, guar. A first step may be the manufacturing of a tobacco slurry by mixing the above ingredients. The slurry may be a watery mixture of insoluble matter with a high water content, for instance of 70 percent - 80 percent. In a second step, the slurry may be put inside a casting box to be casted by a casting knife on a moving conveyor to create a continuous sheet.

[0069] The band of material may comprise, or may be substantially made of, or may be made of poly lactic acid (PI_A). The band of material may comprise, or may be substantially made of, or may be made of cellulose-based material. The band of material may comprise, or may be substantially made of, or may be made of paper.

[0070] The crimped band of material may be incorporated into a component of an aerosolgenerating article which is configured to cool down heated air flows passing into the article before reaching a user. The crimped band of material may be incorporated into a filter element of an aerosol-generating article.

[0071] In the finished article, the crimped band will usually be cut into pieces and included as a folded sheet within a cylindrical plug. In order to create such cylindrical plugs, the main material of the plugs (e.g., TCL, PLA,...), usually provided in a band format (i.e., thin & continuous band of material having a width between about 5 cm to 20 cm), may be submitted to various successive treatments. One of these treatments is the crimping process, for which bands of materials are fed to a pair of interleaved rollers (“crimping rollers”) able to impress a plurality of crimp corrugations on the bands.

[0072] The crimping station may comprise a laser protection air jet system. The laser protection air jet system may be configured to shield a laser source of the laser cleaning system from loose waste material.

[0073] The crimping station may comprise a vacuum system. The vacuum system may be configured to vacuum loose waste material.

[0074] The vacuum system may comprise a cover. The cover may be at least partly covering the laser cleaning system. The cover may be at least partly covering the air jet cleaning system. The vacuum system may comprise an exit tube for the waste material to exit a volume covered by the cover. The vacuum system may comprise a bell-shaped cover. The bell-shaped cover may be at least partly covering the laser cleaning system. The bell-shaped cover may be at least partly covering the air jet cleaning system. The vacuum system may comprise an exit tube for the waste material to exit a volume covered by the bell-shaped cover.

[0075] The at least one crimping roller may comprise a pair of crimping rollers. The at least one crimping roller may be a pair of crimping rollers.

[0076] The pair of crimping rollers may comprise a first crimping roller and a second crimping roller. The laser cleaning system may be a first laser cleaning system configured to direct a laser beam onto a surface of the first crimping roller.

[0077] The air jet cleaning system may be a first air jet cleaning system configured to direct a stream of compressed air onto a surface of the first crimping roller.

[0078] The crimping station may comprise a second laser cleaning system configured to direct a laser beam onto a surface of the second crimping roller.

[0079] The crimping station may comprise a second air jet cleaning system configured to direct a laser beam onto a surface of the second crimping roller.

[0080] The crimping station may comprise a first vacuum system for the first crimping roller and a second vacuum system for the second crimping roller. The crimping station may comprise a common vacuum system for both the first crimping roller and the second crimping roller. The common vacuum system may comprise a common cover. The common cover may be at least partly covering both the first and second laser cleaning systems. The common cover may be at least partly covering both the first and second air jet cleaning systems.

[0081] The first crimping roller and the second crimping roller may be identical. Identical crimping rollers may help lowering costs of the device. The first and second laser cleaning systems may be identical. The first and second air jet cleaning systems may be identical. Identical systems may help lowering costs of the device.

[0082] Both crimping rollers may be subject to cleaning as described herein.

[0083] Determination of target areas for cleaning may undergo an initial learning stage (before real application to manufacturing process) where different samples of crimping waste are put on the rollers and where different areas of these wastes are targeted by the laser beam, optionally followed by the compressed air jets, to see where the best points are to target with the laser and the air jets to unstick the waste according to the waste initial shape and configuration.

[0084] Using the known rotational speed of the crimping roller and the distances between the zone scanned by the detection system, the zone covered by the laser beam and the zone covered by the air jets system, the target areas localizations determined by the detection system may be adjusted to fit correct localization in the laser and air jets zones.

[0085] According to an embodiment of the invention there is provided an apparatus for manufacturing aerosol-generating articles, the apparatus comprising the crimping station as described herein.

[0086] An apparatus for manufacturing aerosol-generating articles with effective cleaning of crimping rollers may be provided. An apparatus for manufacturing aerosol-generating articles which allows to clean crimping rollers at high speed may be provided. An apparatus for manufacturing aerosol-generating articles which allows to clean crimping rollers without damaging the crimping rollers may be provided. An apparatus for manufacturing aerosolgenerating articles which allows to clean crimping rollers without excessively heating up the crimping rollers may be provided.

[0087] The apparatus may comprise means to incorporate the crimped band of material into a rod element of an aerosol-generating article.

[0088] According to an embodiment of the invention there is provided a method for cleaning a crimping roller of an apparatus for manufacturing an aerosol-generating article. The method may comprise a cleaning step of directing a laser beam onto a surface of the crimping roller.

[0089] According to an embodiment of the invention there is provided a method for cleaning a crimping roller of an apparatus for manufacturing an aerosol-generating article. The method comprises a cleaning step of directing a laser beam onto a surface of the crimping roller.

[0090] A method for effectively cleaning of crimping rollers may be provided. A method for cleaning of crimping rollers at high speed may be provided. A method for cleaning of crimping rollers without damaging the crimping rollers may be provided. A method for cleaning of crimping rollers without excessively heating up the crimping rollers may be provided.

[0091] The cleaning step of directing a laser beam onto the surface of the crimping roller may comprise vaporizing waste material from the surface of the crimping roller. The cleaning step of directing a laser beam onto the surface of the crimping roller may comprise removing waste material from the surface of the crimping roller. The waste material may be organic material.

[0092] The method may comprise a cleaning step of directing a stream of compressed air onto the surface of the crimping roller. The cleaning step of directing a stream of compressed air onto the surface of the crimping roller may comprise removing waste material from the surface of the crimping roller. The waste material may be organic material.

[0093] The cleaning step of directing a laser beam onto a surface of the crimping roller may be a first cleaning step. The cleaning step of directing a stream of compressed air onto the surface of the crimping roller may be a second cleaning step. The second cleaning step may be executed after the first cleaning step.

[0094] The method may comprise, before the cleaning step of directing a laser beam onto a surface of the crimping roller, a step of localizing a target area comprising waste material on the surface of the crimping roller.

[0095] The cleaning step of directing a laser beam onto a surface of the crimping roller may comprise moving the laser beam onto the target area.

[0096] Below, there is provided a non-exhaustive list of non-limiting examples. Any one or more of the features of these examples may be combined with any one or more features of another example, embodiment, or aspect described herein.

[0097] Example E1 : A crimping station for an apparatus for manufacturing aerosolgenerating articles, the crimping station comprising at least one crimping roller; and a laser cleaning system configured to direct a laser beam onto a surface of the crimping roller.

[0098] Example E2: The crimping station according to Example E1 , wherein the laser cleaning system is configured to vary the direction of the laser beam to allow selectively guiding the laser beam onto different areas on the surface of the crimping roller.

[0099] Example E3: The crimping station according to Example E1 or Example E2, wherein the laser cleaning system is configured to guide the laser beam onto the surface of the crimping roller at an angle of between 75 degrees and 105 degrees, preferably between 80 degrees and 100 degrees, more preferably between 85 degrees and 95 degrees, with respect to a tangent to the surface of the crimping roller. Example E4: The crimping station according to any of the preceding examples, wherein the laser cleaning system is configured to selectively guide the laser beam onto top parts of ridges on the surface of the crimping roller.

[0100] Example E5: The crimping station according to any of the preceding examples, comprising an air jet cleaning system configured to direct a stream of compressed air onto the surface of the crimping roller.

[0101] Example E6: The crimping station according to Example E5, wherein the air jet cleaning system is configured to vary the direction of the stream of compressed air to allow selectively guiding the stream of compressed air onto different areas on the surface of the crimping roller.

[0102] Example E7: The crimping station according to Example E5 or Example E6, wherein the air jet cleaning system is configured to guide the stream of compressed air onto the surface of the crimping roller at an angle of 15 degrees or less, preferably 10 degrees or less, more preferably 5 degrees or less, with respect to a tangent to the surface of the crimping roller.

[0103] Example E8: The crimping station according to Example E7, wherein the air jet cleaning system is positioned with respect to a rotational direction of the crimping roller such that the stream of compressed air and the surface of the crimping roller move towards each other in an area where the stream of compressed air contacts the surface of the crimping roller.

[0104] Example E9: The crimping station according to any of Examples E5 to E8, wherein the air jet cleaning system is configured to provide a plurality of streams of compressed air onto the surface of the crimping roller, wherein the streams of compressed air of the plurality of streams of compressed air are configured to be guided onto the surface of the crimping roller at different angles.

[0105] Example E10: The crimping station according to any of Examples E5 to E9, wherein the air jet cleaning system is configured to provide a constant stream of compressed air onto the surface of the crimping roller.

[0106] Example E11 : The crimping station according to any of Example E5 to E10, wherein the crimping station is configured such that an area on the surface of the crimping roller is first cleaned by the laser cleaning system and afterwards cleaned by the air jet cleaning system.

[0107] Example E12: The crimping station according to any of the preceding examples, comprising a detection system configured to detect waste material located on the surface of the crimping roller.

[0108] Example E13: The crimping station according to Example E12, wherein the detection system is configured as an image capture detection system comprising a camera.

[0109] Example E14: The crimping station according to Example E12 or Example E13, wherein the detection system comprises an infra-red sensor for detecting the waste material on the surface of the crimping roller based on a temperature difference between the waste material and the crimping roller.

[0110] Example E15: The crimping station according to any of Examples E12 to E14, wherein the detection system comprises a distance sensor for detecting the waste material on the surface of the crimping roller based on a measured distance between the distance sensor and the crimping roller.

[0111] Example E16: The crimping station according to any of Examples E12 to E15, wherein the detection system is configured to locate a position of the waste material on the surface of the crimping roller and, based on the position, identify a target area on the surface of the crimping roller for the laser cleaning system.

[0112] Example E17: The crimping station according to any of Examples E12 to E16, wherein the laser cleaning system is configured to adjust one or both of a power of the laser beam and an exposure time of the laser beam based on information received from the detection system.

[0113] Example E18: The crimping station according to a combination of any of Examples E5 to E11 and any of Examples E12 to E17, wherein the detection system comprises a first detection subsystem for detecting waste material located on the surface of the crimping roller before being cleaned by the laser cleaning system, and a second detection subsystem for detecting waste material located on the surface of the crimping roller before being cleaned by the air jet cleaning system.

[0114] Example E19: The crimping station according to a combination of any of Examples E5 to E11 and any of Examples E12 to E18, wherein the air jet cleaning system is configured to adjust one or both of a power of the stream of compressed air and an exposure time of the stream of compressed air based on information received from the detection system.

[0115] Example E20: The crimping station according to any of the preceding examples, wherein the laser beam has a wavelength of between 200 nanometers and 500 nanometers, or between 700 nanometers and 1300 nanometers, or between 7 micrometers and 13 micrometers.

[0116] Example E21 : The crimping station according to any of the preceding examples, wherein the laser cleaning system comprises one or more of a CO2 laser, an UV laser, and a fiber laser.

[0117] Example E22: The crimping station according to Example E21 , wherein the laser cleaning system comprises a CO2 laser and an UV laser.

[0118] Example E23: The crimping station according to any of the preceding examples, wherein the laser cleaning system comprises a pulsed laser.

[0119] Example E24: The crimping station according to any of the preceding examples, comprising a laser protection air jet system configured to shield a laser source of the laser cleaning system from loose waste material. Example E25: The crimping station according to any of the preceding examples, comprising a vacuum system configured to vacuum loose waste material.

[0120] Example E26: The crimping station according to Example E25, wherein the vacuum system comprises a bell-shaped cover at least partly covering the laser cleaning system; and an exit tube for the waste material to exit a volume covered by the bell-shaped cover. Example E27: The crimping station according to any of the preceding examples, wherein the at least one crimping roller comprises a pair of crimping rollers.

[0121] Example E28: The crimping station according to Example E27, wherein the pair of crimping rollers comprises a first crimping roller and a second crimping roller, and wherein the laser cleaning system is a first laser cleaning system configured to direct a laser beam onto a surface of the first crimping roller.

[0122] Example E29: The crimping station according to Example E28, comprising a second laser cleaning system configured to direct a laser beam onto a surface of the second crimping roller.

[0123] Example E30: An apparatus for manufacturing aerosol-generating articles, the apparatus comprising the crimping station according to any of the proceeding examples.

[0124] Example E31 : A method for cleaning a crimping roller of an apparatus for manufacturing an aerosol-generating article, the method comprising a cleaning step of directing a laser beam onto a surface of the crimping roller.

[0125] Example E32: The method according to Example E31 , comprising a cleaning step of directing a stream of compressed air onto the surface of the crimping roller.

[0126] Example E33: The method according to Example E32, wherein the cleaning step of directing a laser beam onto a surface of the crimping roller is a first cleaning step; wherein the cleaning step of directing a stream of compressed air onto the surface of the crimping roller is a second cleaning step; and wherein the second cleaning step is executed after the first cleaning step.

[0127] Example E34: The method according to any of Examples E31 to E33, comprising, before the cleaning step of directing a laser beam onto a surface of the crimping roller, a step of localizing a target area comprising waste material on the surface of the crimping roller.

[0128] Example E35: The method according to Example E34, wherein the cleaning step of directing a laser beam onto a surface of the crimping roller comprises moving the laser beam onto the target area.

[0129] Features described in relation to one embodiment may equally be applied to other embodiments of the invention.

[0130] The invention will be further described, by way of example only, with reference to the accompanying drawings in which: Fig. 1 shows a crimping station;

[0131] Figs. 2a and 2b show parts of the crimping station of Fig. 1 ;

[0132] Figs. 3a and 3b show a crimping roller surface;

[0133] Fig. 4 shows cleaning of a crimping roller;

[0134] Fig. 5 shows a method for cleaning a crimping roller; and

[0135] Fig. 6 shows a crimping station.

[0136] Fig. 1 schematically shows a crimping station for an apparatus for manufacturing aerosol-generating articles. The crimping station comprises a pair of a first crimping roller 10 and a second crimping roller 12. The first crimping roller 10 rotates along a first direction 110. The second crimping roller 12 rotates along a second direction 112.

[0137] A band of material 14 is directed from an upstream end 100 of the crimping station through a gap between the first and second crimping rollers 10, 12. The band of material 14 is being crimped by the crimping rollers 10, 12 when passing through the gap between the crimping rollers 10, 12. The crimped band of material 14’ is directed towards the downstream end 102 of the crimping station. The crimped band of material 14’ may then be further incorporated into an inhaler article.

[0138] The crimping station comprises a laser cleaning system 20 configured to direct a laser beam 22 onto a surface of the first crimping roller 10. The crimping station comprises an air jet cleaning system 30 configured to direct a stream of compressed air 32 onto the surface of the first crimping roller 10. The crimping station is configured such that an area on the surface of the first crimping roller 10 is first cleaned by the laser cleaning system 20 and afterwards cleaned by the air jet cleaning system 30.

[0139] The crimping station comprises a detection system 40. The detection system 40 is configured to detect waste material 15 located on the surface of the first crimping roller 10. The waste material 15 may be residual material of the band of material 14, 14’ sticking to the surface of the first crimping roller 10 from the crimping process.

[0140] The crimping station comprises a vacuum system. The vacuum system is configured to vacuum loose waste material 15’. The vacuum system comprises a bell-shaped cover 50 covering both the laser cleaning system 20 and the air jet cleaning system 30. The vacuum system comprises an exit tube 52 for the waste material 15’ to exit a volume covered by the bell-shaped cover 50.

[0141] Following the rotational direction 110 of the first crimping roller 11 , an area on the surface of the first crimping roller 10 is first analyzed by the detection system 40, then cleaned by the laser beam 22, and, then, cleaned by the stream of compressed air 32. During use, the two crimping rollers 10 and 12 are crimping the band of material 14, 14'. Due to the crimping, there may remain waste material 15 (stemming from the band of material 14, 14’) on the crimping rollers, for example on the first crimping roller 10.

[0142] In a first step, the detection system 40 identifies and localizes such waste material 15, and defines a target area for the downstream a laser cleaning system 20 and the air jet cleaning system 30. The target area is an area on the surface of the crimping roller 10 which comprises waste material 15. To do this, for example, the detection system 40 may comprise a camera, capturing images of the crimping roller 10 which may be analyzed to identify and localize the waste material 15. By the rotation of the crimping roller 10, the target area moves into a cleaning zone. The cleaning zone comprises the laser cleaning system 20 and the air jet cleaning system 30 and is covered by the bell-shaped cover 50 of the vacuum system.

[0143] The laser cleaning system 20 then focuses the laser beam 22 on the target area of the waste 15, at an approximately perpendicular angle to the surface of the roller 10 comprising the waste 15 thereon, to vaporize the most stuck areas of the waste 15 on the roller 10. Then, the air jet cleaning system 30, sends a stream of compressed air 32 at an approximately tangential angle and ahead of the waste 15, to pull off the roller surface the remaining waste 15. The large bell-shaped cover 50 of the vacuum system covering the cleaning zone creates a strong suction action driving all the loose debris 15’ inside its exit tube 52, assuring they are not contaminating incoming band of material 14 or other machines. The shape of the large bell-shaped cover 50 and the position of the exit tube 52 at a bottom of the bell-shaped cover 50 are exemplarily shown and may be varied. For example, the exit tube 52 may be installed in a top region of the bell-shaped cover 50 and in close proximity to the roller 10.

[0144] Figs. 2a and 2b each show part of the crimping station of Fig. 1 whilst omitting several details to visualize the angles of impingement of the laser beam 22 (Fig. 2a) and the stream of compressed air 32 (Fig. 2b) onto the surface of the first crimping roller 10.

[0145] As shown in Fig. 2a, the laser cleaning system 20 is configured to guide the laser beam 22 onto the surface of the first crimping roller 10 at an angle 24 of approximately 80 degrees or more, with respect to a first tangent 16 to the surface of the first crimping roller 10. The first tangent 16 is a tangent to the first crimping roller 10 at the point 26 where the laser beam 22 impinges onto the surface of the first crimping roller 10. The laser cleaning system 20 is thus configured to guide the laser beam 22 onto the surface of the first crimping roller 10 in an approximately perpendicular direction.

[0146] As shown in Fig. 2b, the air jet cleaning system 30 is configured to guide the stream of compressed air 32 onto the surface of the first crimping roller 10 at an angle 34 of approximately 10 degrees or less, with respect to a second tangent 18 to the surface of the first crimping roller 10. The second tangent 18 is a tangent to the first crimping roller 10 at the point 36 where the stream of compressed air 32 impinges onto the surface of the first crimping roller 10. The air jet cleaning system 30 is thus configured to guide the stream of compressed air 32 onto the surface of the first crimping roller 10 in an approximately tangential direction. Also, the air jet cleaning system 30 is positioned with respect to a rotational direction 110 of the first crimping roller 10 such that the stream of compressed air 32 and the surface of the first crimping roller 10 move towards each other at the point 36 where the stream of compressed 32 air contacts the surface of the first crimping roller 10.

[0147] In the embodiment shown in Figs. 1 and 2, point 36 is somewhat downstream of point 26 with respect to the rotational direction 110 of the first crimping roller 10. Consequently, an area on the surface is first cleaned by the laser beam 22. Afterwards, after having rotated a bit further along direction 110, said area is cleaned by the stream of compressed air 32.

[0148] Although not shown in Figs. 1 and 2, the crimping station of Figs, 1 and 2 may comprise second cleaning means for cleaning the second crimping roller 12. The second cleaning means may be analogous to the cleaning means for cleaning the first crimping roller 10 and may comprise a second detection system, a second laser cleaning system, a second air jet cleaning system, and a second vacuum system. The second cleaning means may be arranged downstream of a point where the crimped band of material 14’ leaves the second crimping roller 12 with respect to the rotational direction 112 of the second crimping roller 12.

[0149] Figs. 3a and 3b schematically show a surface of a crimping roller 10, 12 in a front cut view with waste material 15 thereon. The crimping roller 10, 12 may be a first crimping roller 10 or a second crimping roller 12 as shown in Fig. 1. The curvature of the circular surface is omitted for sake of clarity. The surface of the crimping roller 10, 12 comprises ridges 70.

[0150] Fig. 3a shows that thinner adherence areas 72 of the waste material 15 may be on the top of the ridges 70.

[0151] Fig. 3b shows a laser source 28 of the laser cleaning system 20 targeting with its beam 22 the waste portions 72 which are on the top parts of the ridges 70 of the roller, vaporizing 74 most of the waste portions being there, leaving some burnt debris 76. The laser source 28 is movable transversally reported to the crimping roller surface along axis 78, meaning along the width of the crimping roller surface. Movement of the laser source 28 may be accomplished by carrying the laser source 28 on a module 80 moving on a rail 82 under control of a control unit (not shown) of the laser cleaning system 20 in communication with the detection system 40.

[0152] Fig. 4 shows a top view of the surface of a crimping roller 10, 12, flattened for clarity’s sake. Fig. 4 shows an embodiment for cleaning the crimping roller 10, 12 comprising three consecutively executed steps.

[0153] In a first step, the surface is in a detection zone 140 where the detection system 40 detects if and where there are waste portions 15 on the surface.

[0154] Then, in a second step, once the surface has entered into the cleaning zone 150, due to the rotation 110, 112 of the roller 10, 12, the waste enters first in the laser zone 120 where the laser beam 22, moving transversally as indicated by arrows, vaporizes target areas of the waste 15.

[0155] The waste 15 enters then, in a third step, the air streams zone 130 where one or more streams of compressed air 32, here indicated by arrows as a line of air jets all along the transversal width of the roller surface, are applied to the remaining waste 15 to pull it off the surface.

[0156] Fig. 5 shows a block diagram of a method for cleaning a crimping roller of an apparatus for manufacturing an aerosol-generating article.

[0157] In block 1 , a first area of the surface of a crimping roller 10, 12 is within the detection zone 140 of the detection system 40.

[0158] The detection system 40 detects whether there is waste material 15 present in said first area of the surface of a crimping roller 10, 12 as indicated in block 2.

[0159] If the answer is “no”, meaning that no waste material 15 is detected, no cleaning is initiated for said first area and it is waited for a next area of the surface of the crimping roller 10, 12 to be within the detection zone of the detection system 40 following the rotational movement of the crimping roller 10, 12.

[0160] If the answer is “yes”, meaning that waste material 15 is detected, the detection system 40 localizes corresponding one or more target areas comprising the waste material 15 on the surface of the crimping roller 10, 12 as indicated in block 3.

[0161] Then, the laser beam 22 is adjusted to hit the one or more target areas when the respective area is in the laser zone 120 due to the rotational movement of the crimping roller 10, 12. This is indicated in block 4.

[0162] Afterwards, the one or more streams of compressed air 32 hit the respective target area when said target area is in the air streams zone 130 due to the rotational movement of the crimping roller 10, 12. This is indicated in block 5.

[0163] Using a known rotational speed of the crimping roller 10, 12, and the known distances between the detection zone 140, the laser zone 120, and the air streams zone 130, the target areas localizations may be adjusted from the detection zone 140 to the laser zone 120 and to the air streams zone 130.

[0164] Aside this sequential view of the process, all the indicated systems may be used continuously and simultaneously, but, for instance, applied on different waste’s areas.

[0165] Fig. 6 shows a part of a crimping station. The crimping station of Fig. 6 may be the same as the crimping station of Fig. 1 , with the exception that the crimping station of Fig. 6 comprises an additional laser protection air jet system 60. The laser protection air jet system 60 is configured to shield a laser source of the laser cleaning system 20 from loose waste material 15’. The laser protection air jet system 60 sends compressed air 62 in the direction of the roller 10, but above the waste 15 and roller’s surface, in order not to interfere with the effects of the air jet cleaning system 30, which is aiming lower, and to push the flying debris 15’ to prevent them to come into the “line of fire” of the laser beam 22. Pushing these debris 15’ along the roller rotation will not create contamination as they remain inside the vacuum system and so will be suctioned up by it. It may thereby be avoided that the efficiency of the laser beam 22 is “polluted” by vaporization of debris that are already loose and will be suck into the vacuum system.

Claims

CLAIMS1. A crimping station for an apparatus for manufacturing aerosol-generating articles, the crimping station comprising at least one crimping roller; and a laser cleaning system configured to direct a laser beam onto a surface of the crimping roller.

2. The crimping station according to claim 1 , wherein the laser cleaning system is configured to vary the direction of the laser beam to allow selectively guiding the laser beam onto different areas on the surface of the crimping roller.

3. The crimping station according to claim 1 or claim 2, wherein the laser cleaning system is configured to guide the laser beam onto the surface of the crimping roller at an angle of between 75 degrees and 105 degrees, preferably between 80 degrees and 100 degrees, more preferably between 85 degrees and 95 degrees, with respect to a tangent to the surface of the crimping roller.

4. The crimping station according to any of the preceding claims, wherein the laser cleaning system is configured to selectively guide the laser beam onto top parts of ridges on the surface of the crimping roller.

5. The crimping station according to any of the preceding claims, comprising an air jet cleaning system configured to direct a stream of compressed air onto the surface of the crimping roller.

6. The crimping station according to claim 5, wherein the air jet cleaning system is configured to vary the direction of the stream of compressed air to allow selectively guiding the stream of compressed air onto different areas on the surface of the crimping roller.

7. The crimping station according to claim 5 or claim 6, wherein the air jet cleaning system is configured to guide the stream of compressed air onto the surface of the crimping roller at an angle of 15 degrees or less, preferably 10 degrees or less, more preferably 5 degrees or less, with respect to a tangent to the surface of the crimping roller.

8. The crimping station according to claim 7, wherein the air jet cleaning system is positioned with respect to a rotational direction of the crimping roller such that the stream ofcompressed air and the surface of the crimping roller move towards each other in an area where the stream of compressed air contacts the surface of the crimping roller.

9. The crimping station according to any of claims 5 to 8, wherein the crimping station is configured such that an area on the surface of the crimping roller is first cleaned by the laser cleaning system and afterwards cleaned by the air jet cleaning system.

10. The crimping station according to any of the preceding claims, comprising a detection system configured to detect waste material located on the surface of the crimping roller, wherein the detection system is configured to locate a position of the waste material on the surface of the crimping roller and, based on the position, identify a target area on the surface of the crimping roller for the laser cleaning system.

11. The crimping station according to claim 10, wherein the laser cleaning system is configured to adjust one or both of a power of the laser beam and an exposure time of the laser beam based on information received from the detection system.

12. The crimping station according to any of the preceding claims, comprising a laser protection air jet system configured to shield a laser source of the laser cleaning system from loose waste material.

13. The crimping station according to any of the preceding claims, comprising a vacuum system configured to vacuum loose waste material, wherein the vacuum system comprises a bell-shaped cover at least partly covering the laser cleaning system; and an exit tube for the waste material to exit a volume covered by the bell-shaped cover.

14. The crimping station according to any of the preceding claims, wherein an average power of the laser is between 100 Watts and 600 Watts.

15. The crimping station according to any of the preceding claims, wherein the at least one crimping roller comprises a pair of crimping rollers.

16. An apparatus for manufacturing aerosol-generating articles, the apparatus comprising the crimping station according to any of the proceeding claims.

17. A method for cleaning a crimping roller of an apparatus for manufacturing an aerosol-generating article, the method comprising a cleaning step of directing a laser beam onto a surface of the crimping roller.

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