Method for checking manufacturing defects of ventilated zone of aerosol-generating article

Abstract

The invention relates to a method for inspecting manufacturing defects of an aerosol-generating article having a ventilation zone, comprising:-providing an aerosol-generating article having a ventilation zone, the ventilation zone comprising a plurality of perforations,-cutting the aerosol-generating article along a plane passing through the plurality of perforations, thereby producing an intersection through the plurality of perforations, and checking the intersection for manufacturing defects. Such a method for inspecting manufacturing defects of an aerosol-generating article may also inspect the shape and location of perforations within the article.

Description

Technical Field

[0001] The present invention relates to a method for inspecting a ventilation zone of an aerosol-generating article for manufacturing defects. The present invention also relates to an inspection device for inspecting a ventilation zone of an aerosol-generating article for manufacturing defects. Background Art

[0002] The aerosol-generating article comprises: a substrate section comprising an aerosol-forming substrate; and in addition often comprises a ventilation zone comprising a plurality of perforations allowing ambient air to enter the aerosol-generating article. Methods for inspecting the perforations in the ventilation zone for manufacturing defects are generally limited to visual inspection of the final aerosol-generating article comprising the ventilation zone. These methods do not provide any information about the path of the perforations within the aerosol-generating article. Other methods are known which analyze the aerosol-generating article's resistance to draw and the amount of air that can be drawn through the perforations. These methods do not provide information about the geometry of the perforations or their orientation within the article. Summary of the invention

[0003] It is desirable to provide a method for inspecting a ventilation zone of an aerosol-generating article for manufacturing defects, which method is capable of inspecting the path of the perforations in the article. Furthermore, it is desirable to provide a method for inspecting a ventilation zone of an aerosol-generating article for manufacturing defects, which method will provide information about the geometry of the perforations in the article. It is also desirable to provide a method for inspecting manufacturing defects, which method will provide information about the orientation of the perforations in the plane of the ventilation zone. Furthermore, it is desirable to provide an inspection device that can help inspect the perforations of the ventilation zone for manufacturing defects.

[0004] According to an embodiment of the present invention, a method for inspecting an aerosol generating article having a ventilation zone for manufacturing defects is provided. The method may include the method step of providing an aerosol generating article having a ventilation zone. The ventilation zone may include a plurality of perforations. The method may include the method step of cutting the aerosol generating article along a plane passing through the plurality of perforations. This may produce an intersection passing through the plurality of perforations. The method may also include inspecting the intersection for manufacturing defects.

[0005] According to another embodiment of the present invention, there is provided a method for inspecting an aerosol-generating article having a ventilation zone for manufacturing defects. The method comprises:

[0006] - providing an aerosol-generating article having a ventilation zone, the ventilation zone comprising a plurality of perforations,

[0007] - cutting the aerosol-generating article along a plane passing through the plurality of perforations, thereby creating an intersection passing through the plurality of perforations, and

[0008] - Checking the intersection for manufacturing defects.

[0009] The method for inspecting for manufacturing defects may allow inspection of the path of a perforation within a ventilation zone through the aerosol-generating article along the intersection. This may provide additional insight into the construction of the perforations within the aerosol-generating article. The method may allow inspection of the structure of the perforations within the aerosol-generating article for manufacturing defects. This may provide better insight into the structure and path of the perforations within the ventilation zone compared to methods in which the aerosol-generating article is inspected from the outside, for example by using a visual inspection system.

[0010] The term "aerosol generating article" is used herein to refer to an article in which an aerosol generating substrate is heated to generate an inhalable aerosol and deliver it to a consumer. As used herein, the term "aerosol-forming substrate" means a substrate that is capable of releasing volatile compounds to generate an aerosol when heated. The term "aerosol generating article" also includes continuous strips formed from a plurality of aerosol generating articles. During the production of aerosol generating articles, long strips containing up to 10 aerosol generating articles can be formed, which can then be cut to produce smaller strips or final products. In particular, the term "aerosol generating article" also includes so-called "double strips", which are two aerosol generating articles connected together. Such double strips can be subjected to a method for inspecting manufacturing defects as described herein.

[0011] As used herein, the term "aerosol-generating device" refers to a device comprising a heater element that interacts with an aerosol-generating substrate of an aerosol-generating article to generate an aerosol.

[0012] The aerosol-forming substrate may be a solid aerosol-forming substrate.

[0013] In certain preferred embodiments, the aerosol-forming substrate comprises homogenised plant material, preferably homogenised tobacco material.

[0014] As used herein, the term "homogenized plant material" encompasses any plant material formed by the agglomeration of plant particles. For example, sheets or webs of homogenized tobacco material used to form aerosol substrates of the present invention can be formed by agglomerating particles of tobacco material, which particles are obtained by pulverizing, grinding or grinding plant material and one or more of optional tobacco leaves and tobacco stems. Homogenized plant material can be produced by casting, extruding, papermaking technology or other any suitable process known in the art.

[0015] The homogenized plant material may be provided in any suitable form. For example, the homogenized plant material may be in the form of one or more sheets. As used herein with reference to the present invention, the term "sheet" describes a laminar element whose width and length are significantly greater than its thickness.

[0016] The homogenized plant material may be in the form of a plurality of pellets or granules.

[0017] Homogenized plant material can be in the form of multiple thin strips, strips or fragments. As used herein, the term "thin strip" describes an elongated element material whose length is significantly greater than its width and thickness. The term "thin strip" should be considered to include strips, fragments and any other homogenized plant material with similar forms. The thin strips of homogenized plant material can be formed by sheets of homogenized plant material, such as by cutting or chopping, or by other methods, such as by extrusion methods.

[0018] The tobacco particles can have a nicotine content of at least about 2.5% by weight on a dry weight basis. More preferably, the tobacco particles can have a nicotine content of at least about 3% by weight on a dry weight basis, even more preferably at least about 3.2% by weight, even more preferably at least about 3.5% by weight, most preferably at least about 4% by weight.

[0019] The aerosol-forming substrate may further include one or more aerosol formers. Upon volatilization, the aerosol formers may convey in the aerosol other volatile compounds released from the aerosol-forming substrate upon heating, such as nicotine and flavorings. Suitable aerosol formers for inclusion in the homogenized plant material are known in the art and include, but are not limited to: polyols, such as triethylene glycol, propylene glycol, 1,3-butylene glycol and glycerol; esters of polyols, such as glycerol mono-, di- or triacetate; and aliphatic esters of mono-, di- or polycarboxylic acids, such as dimethyl dodecanedioate and dimethyl tetradecanedioate.

[0020] The aerosol-forming agent content of the aerosol-forming substrate may be between about 5 wt % and about 30 wt % on a dry weight basis, such as between about 10 wt % and about 25 wt % on a dry weight basis, or between about 15 wt % and about 20 wt % on a dry weight basis.

[0021] For example, if the substrate is intended for use in an aerosol-generating article of an electrically operated aerosol-generating system having a heating element, it may preferably comprise an aerosol-forming agent content of between about 5 wt% and about 30 wt% on a dry weight basis. If the substrate is intended for use in an aerosol-generating article of an electrically operated aerosol-generating system having a heating element, the aerosol-forming agent is preferably glycerol.

[0022] The aerosol-forming substrate may comprise a gel composition comprising the alkaloid compound. In particularly preferred embodiments, the aerosol-forming substrate comprises a gel composition comprising nicotine.

[0023] Preferably, the gel composition comprises nicotine.

[0024] Preferably, in an aerosol-generating article according to the invention, the susceptor is arranged within the strip of aerosol-forming substrate and is in thermal contact with the aerosol-forming substrate.Preferably, the susceptor is an elongate susceptor.

[0025] As used herein with reference to the present invention, the term "susceptor" refers to a material that can convert electromagnetic energy into heat. When located within a fluctuating electromagnetic field, eddy currents induced in the susceptor cause heating of the susceptor. When the elongated susceptor is placed in thermal contact with the aerosol-forming substrate, the aerosol-forming substrate is heated by the susceptor.

[0026] The term "elongated" when used to describe a susceptor means that the length dimension of the susceptor is greater than its width dimension or its thickness dimension, for example, greater than twice its width dimension or its thickness dimension.

[0027] The susceptor is preferably arranged substantially longitudinally within the strip. This means that the length dimension of the elongated susceptor is arranged substantially parallel to the longitudinal direction of the strip, for example within + / - 10 degrees parallel to the longitudinal direction of the strip. In a preferred embodiment, the elongated susceptor may be located at a radially central position within the strip and extend along the longitudinal axis of the strip.

[0028] Preferably, the susceptor extends all the way to the downstream end of the strip of the aerosol-generating article. In some embodiments, the susceptor may extend all the way to the upstream end of the strip of the aerosol-generating article. In particularly preferred embodiments, the susceptor has substantially the same length as the strip of the aerosol-forming substrate and extends from the upstream end of the strip to the downstream end of the strip.

[0029] The susceptors are preferably in the form of needles, strips, ribbons or blades.

[0030] The susceptor preferably has a length of from about 5 mm to about 15 mm, such as from about 6 mm to about 12 mm, or from about 8 mm to about 10 mm.

[0031] The ratio between the length of the susceptor and the overall length of the aerosol-generating article substrate may be from about 0.2 to about 0.35.

[0032] The susceptor may be formed from any material that can be heated by induction to a temperature sufficient to generate an aerosol from the aerosol-forming substrate. Preferred susceptors comprise metal or carbon.

[0033] Preferred susceptors may include or consist of ferromagnetic materials, such as ferromagnetic alloys, ferritic iron, or ferromagnetic steel or stainless steel. Suitable susceptors may be or include aluminum. Preferred susceptors may be made of 400 series stainless steel, such as grade 410 or grade 420 or grade 430 stainless steel. Different materials will dissipate different amounts of energy when positioned within an electromagnetic field having similar frequency and field strength values.

[0034] Thus, the parameters of the susceptor, such as material type, length, width and thickness, can be altered within a known electromagnetic field to provide the required power dissipation.Preferred susceptors can be heated to temperatures in excess of 250 degrees Celsius.

[0035] Suitable susceptors may include a non-metallic core having a metal layer disposed on the non-metallic core, such as metal traces formed on the surface of a ceramic core. The susceptor may have an outer protective layer, such as a ceramic protective layer or a glass protective layer encapsulating the susceptor. The susceptor may include a protective coating formed of glass, ceramic, or an inert metal formed on the core of the susceptor material.

[0036] The susceptor is arranged in thermal contact with the aerosol-forming substrate. Thus, when the susceptor is heated, the aerosol-forming substrate is heated and an aerosol is formed. Preferably, the susceptor is arranged in direct physical contact with the aerosol-forming substrate, for example within the aerosol-forming substrate.

[0037] The aerosol-generating article may further comprise a downstream section at a position downstream of the strip of aerosol-forming substrate. The downstream section may comprise an intermediate hollow section comprising an aerosol-cooling element arranged to align with the strip of aerosol-forming substrate and located downstream of the strip of aerosol-forming substrate.

[0038] The downstream section may also include one or more downstream elements on top of the aerosol-cooling element. For example, the intermediate hollow section may further include a support element positioned immediately downstream of the strip of aerosol-forming substrate, and the aerosol-cooling element may be located between the support element and the downstream end (or mouth end) of the aerosol-generating article. In more detail, the aerosol-cooling element may be positioned immediately downstream of the support element. In some preferred embodiments, the aerosol-cooling element may be adjacent to the support element. As will be described below, the downstream section may further include one or more elements on top of the intermediate hollow section at a position downstream of the intermediate hollow section.

[0039] The aerosol-cooling element may comprise a hollow tubular segment defining a cavity extending from an upstream end of the aerosol-cooling element to a downstream end of the aerosol-cooling element, and the ventilation zone may be provided at a location along the hollow tubular segment.

[0040] As used herein, the term "hollow tubular segment" is used to refer to a generally elongated element that defines an inner cavity or airflow passage along its longitudinal axis. In particular, the term "tubular" will be used hereinafter to refer to a tubular element having a substantially cylindrical cross-section and defining at least one airflow conduit that establishes uninterrupted fluid communication between the upstream end of the tubular element and the downstream end of the tubular element. However, it should be understood that alternative geometries (e.g., alternative cross-sectional shapes) of the tubular element may be possible.

[0041] In the context of the present invention, the hollow tubular segment provides a non-restrictive flow channel. This means that the hollow tubular segment provides a negligible level of resistance to draw (RTD). Therefore, the flow channel should not contain any components that would hinder the flow of air in the longitudinal direction. Preferably, the flow channel is substantially empty.

[0042] The term "elongated" when used to describe an aerosol-cooling element means that the aerosol-cooling element has a length dimension that is greater than its width dimension or its diameter dimension, for example twice its width dimension or its diameter dimension or more.

[0043] As used herein, the term "longitudinal" refers to a direction corresponding to the main longitudinal axis of the aerosol-generating article, which direction extends between the upstream end and the downstream end of the aerosol-generating article. As used herein, the terms "upstream" and "downstream" describe the relative position of an element or part of an element of an aerosol-generating article relative to the direction in which an aerosol is transported through the aerosol-generating article during use.

[0044] The plurality of perforations in the ventilation zone may include at least 2 perforations. The plurality of perforations in the ventilation zone may include at least 4, preferably at least 6 perforations. More preferably, the plurality of perforations may include up to 15, preferably up to 11 perforations in the ventilation zone.

[0045] The aerosol-generating article may comprise a central longitudinal axis. Cutting the aerosol-generating article along a plane passing through the plurality of perforations may comprise cutting the aerosol-generating article in the ventilation zone in a plane transverse to the central longitudinal axis. Preferably, the aerosol-generating article is cut perpendicularly to the central longitudinal axis in its ventilation zone.

[0046] This can provide a cross-sectional cut of a plurality of perforations within the ventilation area. This can allow the width and length of the perforations within the ventilation area to be inspected for manufacturing defects.

[0047] Cutting the aerosol-generating article along a plane passing through the plurality of perforations may provide a cut piece of the aerosol-generating article wherein one end of the cut piece forms an intersection passing through the ventilation zone. This cut piece of the aerosol-generating article having the intersection may then be used in a method for inspecting for manufacturing defects.

[0048] The method can provide a cross-sectional cut of all perforations in the ventilation area. Thus, all perforations in the ventilation area can be inspected for manufacturing defects by inspecting the intersections.

[0049] The perforation may comprise a hole extending from the exterior of the aerosol-generating article into the interior of the aerosol-generating article.The cross-sectional cut of the perforation may thus comprise an elongated shape, preferably a rectangular shape.

[0050] The aerosol-generating article may be cut through the hollow segment including the ventilation area. Then, inspecting for manufacturing defects may include inspecting whether at least one cross-sectional cut of the perforation extends from the interior of the hollow segment to the exterior of the aerosol-generating article. Inspecting for manufacturing defects may include rejecting aerosol-generating articles whose cross-sectional cut does not extend from the interior of the hollow segment to the exterior of the aerosol-generating article.

[0051] The number of perforated cross-sectional cuts extending from the interior of the hollow segment to the exterior of the aerosol-generating article may be determined. If less than two-thirds of the cross-sectional cuts of the aerosol-generating article do not extend from the interior of the hollow segment to the exterior of the aerosol-generating article, the aerosol-generating article may be rejected.

[0052] At least one cross-sectional cut of the perforation in the intersection may be inspected for manufacturing defects. Preferably, at least 2 or at least 3 cross-sectional cuts are inspected for manufacturing defects. Most preferably, all cross-sectional cuts of the perforation are inspected for manufacturing defects.

[0053] This can allow for a quick inspection of intersections by inspecting only a portion of the cross-sectional cuts of the plurality of perforations. This can speed up the inspection process for manufacturing defects. Alternatively, all cross-sectional cuts of the perforations can be inspected for manufacturing defects. This method can provide a very accurate assessment of manufacturing defects.

[0054] The tubular sacrificial element may be used during cutting of the aerosol-generating article. The tubular sacrificial element may have a slightly larger diameter than the aerosol-generating article. The tubular sacrificial element may be slid over the aerosol-generating article before cutting the article.

[0055] The tubular sacrificial element may comprise a plastic tube or housing. The tubular sacrificial element may comprise an indicator indicating the intended location of the perforations within the ventilation zone. The indicator may comprise markings on the tubular sacrificial element.

[0056] After the tubular sacrificial element has been slid over the aerosol-generating article, the tubular sacrificial element containing the aerosol-generating article may be cut.Preferably, the aerosol-generating article may be cut through an indicator of the tubular sacrificial element.

[0057] This may facilitate positioning any cutting device in a correct way.The tubular sacrificial element may mechanically stabilize the aerosol-generating article during the cutting procedure.This may avoid any deformation of the aerosol-generating article, in particular in the region of intersections formed by the cutting process.

[0058] The aerosol-generating article may be cut by using a cutting device. The cutting device may be, for example, a rotating knife or a filter cutter.

[0059] A reference image of the cross-sectional cut of the perforation may be provided. The reference image may be superimposed on the cross-sectional cut of the perforation in the intersection of the aerosol-generating article. This may allow visual inspection for manufacturing defects. Preferably, one or both of the width or orientation of the cross-sectional cut in the intersection may be inspected by using the reference image.

[0060] Using a reference image may allow for a quicker and easier visual inspection of manufacturing defects of the perforations. In particular, the width of the reference image may be compared to the width of at least some of the cross-sectional cuts of the perforations in the intersection. This may allow for easy inspection of manufacturing defects related to the width. The reference image may indicate the correct position of the cross-sectional cuts of the perforations within the intersection. Thus, the reference image may allow for easy inspection of potential manufacturing defects related to the orientation of the perforations within the ventilation zone.

[0061] The reference image may be positioned above the intersection to visually inspect for manufacturing defects. The reference image and the intersection of the cut aerosol-generating article may be rotatably arranged relative to each other. The reference image may be superimposed on at least one cross-sectional cut of the perforation via rotation.

[0062] Rotating the reference image relative to the perforated cross-sectional cut may provide a simple method for superimposing the reference image on the cross-sectional cut.

[0063] In one embodiment of the method for inspecting manufacturing defects, the reference image may be successively superimposed with at least some of the cross-sectional cuts of the perforation by rotating the reference image relative to the cross-sectional cuts in order to inspect for manufacturing defects.

[0064] The aerosol-generating article may comprise a central longitudinal axis. The rotation of the reference image and the cross-sectional cut relative to each other may be performed around the central longitudinal axis of the aerosol-generating article. In particular, the rotational movement may be centered about the central longitudinal axis of the cut aerosol-generating article. This may provide a simple way of superimposing the reference image on at least some of the perforated cross-sectional cuts.

[0065] The inclination of the cross-sectional cut of the perforation relative to the cutting plane can be determined. In particular, due to the inclination of the perforation relative to the cutting plane, the cross-sectional cut of the perforation in the intersection may not extend continuously from the outside of the aerosol generating article to the inside of the article. Therefore, partial cross-sectional cuts in the intersection that do not extend from the outside of the aerosol generating article to the inside can be regarded as manufacturing defects. Therefore, in the method for checking for manufacturing defects, aerosol generating articles including these partial cross-sectional cuts in their intersection can be rejected. The method for checking for manufacturing defects of the present invention can therefore also determine whether the perforations in the ventilation zone have the correct orientation within the plane of the ventilation zone.

[0066] The reference image may be an image of a correctly positioned and correctly shaped cross-sectional cut. The reference image may also be of the correct width.

[0067] An area of ​​the reference image that can be superimposed on the area of ​​the perforated cross-sectional cut can be determined. This can allow a technician to determine the percentage of overlap between the area of ​​the reference image and the perforated cross-sectional cut. A low percentage of the superimposable area of ​​the reference image can indicate a large deviation between the reference image and the perforated cross-sectional cut in the intersection of the aerosol generating article. If the deviation between its perforated cross-sectional cut in the intersection and the reference image is too large, the aerosol generating article may be rejected. If less than 80%, preferably less than 85%, more preferably less than 90% of the area of ​​the reference image can be superimposed on the area of ​​the perforated cross-sectional cut, the aerosol generating article may be rejected.

[0068] Furthermore, the aerosol generating article may be rejected if less than 80%, preferably less than 85%, and more preferably less than 90% of the total number of cross-sectional cuts of the perforations in the intersection can be superimposed to such an extent that at least 80% of the area of ​​the reference image can be superimposed on the area of ​​the corresponding cross-sectional cuts as described above.

[0069] Therefore, small deviations of up to 20%, preferably up to 10%, between the area of ​​the reference image and the area of ​​the cross-sectional cut may be tolerable. These small deviations may still allow sufficient resistance to drawing and, as ambient air enters the aerosol-generating article through the perforations, may allow sufficient temperature regulation of the aerosol in the ventilation zone of the aerosol-generating article.

[0070] By using a computed CT scan, the percent overlap of the area of ​​the reference image and the area of ​​the cross-sectional cut of the perforation in the intersection can be determined. Some method steps or the complete method of inspecting the ventilation zone of an aerosol-generating article for manufacturing defects may include a computer-implemented method. The reference image may be a computer-generated image, or may be implemented in an inspection tool, as further described below.

[0071] An aerosol-generating article may be rejected if the central axis of the cross-sectional cut of the perforation in the intersection of the aerosol-generating article has an inclination angle greater than 10 degrees, preferably greater than 5 degrees, relative to the reference image.

[0072] Such a large tilt angle may indicate that the perforations are tilted to such a large extent compared to the reference image that the aerosol-generating article must be rejected.

[0073] If the center axis of the cross-sectional cut lies completely within the reference image, the perforation has passed the method for detecting manufacturing defects.

[0074] The tilt angle between the central axis of the cross-sectional cut and the reference image may be determined as a cutting angle between the central axis of the cut and the reference image.

[0075] In particular, when the reference image cannot be superimposed on the cross-sectional cut of the perforation in the intersection, the aerosol-generating article may be rejected. This may indicate the extent to which the perforation is offset from the reference image to which the aerosol-generating article must be rejected.

[0076] The reference image can include one of the following:

[0077] - lines indicating the width and position of a correctly positioned and correctly formed cross-sectional cut, or

[0078] - an arc of a circle indicating the area in which the central axis of the cross-sectional cut of the perforation should be located.

[0079] A reference image including lines indicating the width and position of a correctly positioned and correctly shaped cross-sectional cut may be used in order to determine the degree of overlap between an area of ​​the reference image and an area of ​​the cross-sectional cut.

[0080] A reference image comprising an arc of a circle may be used in order to determine the above-mentioned tilt angle between the central axis of the cross-sectional cut and the reference image.

[0081] Inspection tools may be used to inspect for manufacturing defects. The inspection tools may include:

[0082] - a cavity for receiving a cut piece of the aerosol-generating article, wherein the cut piece comprises the intersection,

[0083] - reference images of cross-sectional cuts of the perforations, and

[0084] - means for rotating the reference image and the cut aerosol-generating article relative to each other for superimposing the reference image on the perforated cross-sectional cut in the intersection.

[0085] Such a tool may be conveniently used to easily superimpose a reference image onto a perforated cross-sectional cut.In particular, a cut piece of the aerosol-generating article comprising the intersection may be housed in the cavity.

[0086] The bottom of the cavity may comprise a transparent material. This may allow a user to view the intersection of the cut pieces of the aerosol-generating article when the cut pieces are housed in the cavity.

[0087] The reference image may be located adjacent to the bottom of the cavity.This may allow a user of the inspection tool to easily superimpose the reference image on any cross-sectional cuts of perforations located in the intersection of cut pieces of the aerosol-generating article.

[0088] The reference image may be comprised in a transparent reference element of the inspection tool.The transparent reference element may be configured to be rotatable relative to the cavity, in particular relative to a transparent bottom of the cavity of the inspection tool.

[0089] The inspection tool may be configured to enable a user to view the intersection of the cut pieces of the aerosol-generating article through the transparent reference element and the transparent bottom of the cavity.

[0090] This may allow a user to easily visually inspect the cross-sectional cut of the perforation within the intersection by superimposing a reference image onto the cross-sectional cut via rotational movement of the transparent reference element relative to the transparent bottom of the cavity.

[0091] The inspection tool may further comprise a light source for illuminating the intersection and the reference image. This may facilitate visual inspection of the intersection for manufacturing defects.

[0092] The inspection tool may further comprise a magnifying device. The magnifying device may be configured to provide a magnified image of the intersection of the cut pieces of the aerosol-generating article comprising the perforated cross-sectional cut. The magnifying device may facilitate visual inspection of the intersection for the presence of manufacturing defects. The magnifying device may comprise or may consist of a magnifying lens.

[0093] A magnifying device can facilitate manual visual inspection of any manufacturing defects.

[0094] If an upscaling device is used, the reference image may include one of the following:

[0095] - lines indicating the width and location of a correctly positioned and correctly shaped enlarged cross-sectional cut, or

[0096] - A circular arc indicating the area in which the central axis of the enlarged cross-sectional cut of the perforation should be located.

[0097] In particular, the reference image may be adapted to indicate the width and position of a correctly positioned and correctly shaped cross-sectional cut magnified by the magnifying device, or may comprise an arc indicating the area in which the central axis of the perforated cross-sectional cut magnified by the magnifying device should be located.

[0098] The reference image may be located on the magnifying device. This may facilitate superimposing the reference image onto an enlarged cross-sectional cut of the intersection of the cut pieces of the aerosol-generating article.

[0099] The magnification device may facilitate manual visual inspection of any manufacturing defects by a user of the inspection tool.

[0100] The bottom of the cavity of the inspection tool may be located within the focal length of the magnifying device. This may allow sufficient magnification of the intersection of the cut pieces of the product.

[0101] The magnification device may provide a magnification factor of between 1.5 and 10, preferably between 2 and 6.

[0102] The plurality of perforations in the ventilation zone of the aerosol-generating article may extend radially from the central longitudinal axis of the article.

[0103] Checking for manufacturing defects in the intersection may then include checking whether the cross-sectional cut of the perforation is tilted relative to its radial extension from the central longitudinal axis.

[0104] If the cross-sectional cut of the perforation in the intersection of this article is inclined more than 20 degrees, preferably more than 5 degrees, relative to its radial extension, the aerosol-generating article may be rejected.

[0105] The intersections of the cut pieces of the aerosol-generating article may be coloured in order to increase the contrast between the perforations and the wall of the aerosol-generating article.

[0106] This can facilitate visual inspection of the cross-sectional cut of the perforation.

[0107] The dyeing may be accomplished by contacting the intersections with a dye, such as ink.

[0108] The aerosol-generating article may be tubular, and the perforations may be arranged circumferentially around the tubular aerosol-generating article.

[0109] Using the methods described herein, particularly methods involving reference images, intersections of such aerosol generating articles can be easily inspected for manufacturing errors. The reference image can be easily superimposed on at least some of the perforated cross-sectional cuts by rotating the reference image relative to the cross-sectional cuts.

[0110] The method step of inspecting the intersection for manufacturing defects may comprise two separate inspection steps. In a first initial inspection step, the number of complete cross-sectional cuts of the perforations of the intersection of the aerosol generating article extending from the exterior of the article into the interior of the article may be determined. If the number of complete cross-sectional cuts is above a threshold, one or more of the position of the cross-sectional cuts within the intersection, the shape of the cross-sectional cuts and the angle of the cross-sectional cuts relative to the radial extension of the perforations may be inspected in a second inspection step. The threshold may represent a minimum fraction of complete cross-sectional cuts relative to the total number of cross-sectional cuts located in the intersection of the aerosol generating article.

[0111] In a first initial step, the number of cross-sectional cuts of the perforations of the intersection of the aerosol-generating article extending from the outside of the article to the inside of the article may be determined. Partial cross-sectional cuts of perforations that do not extend from the outside of the article to the inside of the article may be considered as manufacturing defects and may not be counted as complete cross-sectional cuts. If less than 40%, preferably less than 30%, more preferably less than 25% of the expected number of cross-sectional cuts extend completely from the outside of the article to the inside of the article, the aerosol-generating article may be rejected and may not be subjected to additional inspection steps for manufacturing defects. This percentage value may represent a threshold value for the first initial inspection step. For example, if it is assumed that the total number of perforations present in the ventilation zone of the aerosol-generating article is 11, and if less than 2 perforations extend completely from the outside of the article to the inside, the aerosol-generating article may be rejected and additional inspection steps involving the article may not be performed. If there are at least 3 perforations that extend completely from the outside of the article to the inside, additional inspection steps, in particular a second inspection step, may be used.

[0112] The present invention also provides an inspection tool for inspecting manufacturing defects in a ventilation zone of an aerosol generating article, wherein the ventilation zone includes a plurality of perforations. The inspection tool may include a cavity for receiving the aerosol generating article, wherein the aerosol generating article is cut along a plane passing through the ventilation zone to produce an intersection passing through the plurality of perforations. The inspection tool may include a reference image of the cross-sectional cut of the perforations. The inspection tool may include means for rotating the reference image and the intersection of the cut aerosol generating article relative to each other for superimposing the reference image on the cross-sectional cut of the perforations within the intersection.

[0113] Another embodiment of the present invention provides an inspection tool for inspecting manufacturing defects in a ventilation zone of an aerosol-generating article, wherein the ventilation zone comprises a plurality of perforations. The inspection tool comprises:

[0114] - a cavity for receiving the aerosol-generating article, wherein the aerosol-generating article is cut along a plane passing through the ventilation zone to create an intersection passing through the plurality of perforations,

[0115] - a reference image of a cross-sectional cut of the perforation, and

[0116] - means for rotating the reference image and the cut aerosol-generating article relative to each other for superimposing the reference image on the perforated cross-sectional cut in the intersection.

[0117] Such inspection tools can facilitate visual inspection of intersections for manufacturing defects.

[0118] The inspection tool may further include a light source for illuminating the intersection and the reference image.

[0119] The light source may also facilitate visual inspection of the intersection.

[0120] The reference image may be included in a transparent rotatable portion of the tool. This may facilitate superimposing the reference image on the cross-sectional cut of the perforation within the intersection.

[0121] The transparent rotatable part of the tool may comprise a magnifying device, such as a magnifying lens.

[0122] As described above with respect to the method of using the inspection tool, the inspection tool may include further features.

[0123] A non-exhaustive list of non-limiting examples is provided below.Any one or more features of these examples may be combined with any one or more features of another example, embodiment or aspect described herein.

[0124] Example A: A method for inspecting an aerosol-generating article having a ventilation zone for manufacturing defects, comprising:

[0125] - providing an aerosol-generating article having a ventilation zone, the ventilation zone comprising a plurality of perforations,

[0126] - cutting the aerosol-generating article along a plane passing through the plurality of perforations, thereby creating an intersection passing through the plurality of perforations, and

[0127] - Inspect the intersection for manufacturing defects.

[0128] Example B: A method according to Example A, wherein at least one cross-sectional cut of the perforation within the intersection is checked for manufacturing defects, preferably wherein at least 2 or 3 cross-sectional cuts of the perforation are checked for manufacturing defects, and more preferably wherein all cross-sectional cuts of the perforation are checked for manufacturing defects.

[0129] Example C: The method of the preceding example, wherein an inclination of the cross-sectional cut of the perforation relative to the plane is determined.

[0130] Example D: A method according to any of the preceding examples, wherein a reference image of a cross-sectional cut of a perforation is provided, and wherein the reference image is superimposed on the cross-sectional cut of the perforation in the intersection of the aerosol generating article for visual inspection of manufacturing defects, preferably wherein one or both of the width or orientation of the cross-sectional cut within the intersection are inspected by using the reference image, and more preferably wherein an area of ​​the reference image that can be superimposed on a cross-sectional cut of a perforation is determined.

[0131] Example E: The method of the preceding example, wherein the reference image is positioned above the intersection, and wherein the reference image and the intersection are rotatably arranged relative to each other, and wherein the reference image is superimposed on a cross-sectional cut of the perforation via rotation.

[0132] Example F: A method according to any of the preceding examples D or E, wherein the aerosol generating article is rejected if less than 80%, preferably less than 90%, of the area of ​​the reference image can be superimposed on the area of ​​the cross-sectional cut of the perforation in the intersection of the aerosol generating article.

[0133] Example G: A method according to any one of the preceding Examples D to F, wherein the aerosol generating article is rejected if the central axis of the cross-sectional cut of the perforation in the intersection of the aerosol generating article has an inclination angle greater than 10 degrees, preferably greater than 5 degrees, relative to the reference image.

[0134] Example H: The method of preceding examples D to G, wherein the aerosol-generating article is rejected when the reference image cannot be superimposed on the cross-sectional cut of the perforation in the intersection.

[0135] Example I: The method of any of the preceding examples D to H, wherein the reference image comprises one of the following:

[0136] - lines indicating the width and location of a correctly positioned and correctly formed cross-sectional cut, or

[0137] - An arc of a circle indicating the area in which the central axis of the cross-sectional cut of the perforation should be located.

[0138] Example J: The method of any of the preceding examples D to I, wherein an inspection tool is used to inspect for manufacturing defects, the inspection tool comprising:

[0139] - a cavity for receiving a cut piece of the aerosol-generating article, wherein the cut piece comprises the intersection,

[0140] - said reference image of a cross-sectional cut of the perforation, and

[0141] - means for rotating the reference image and the cut aerosol-generating article relative to each other for superimposing the reference image on the perforated cross-sectional cut in the intersection.

[0142] Example K: The method of the preceding example, wherein the inspection tool further comprises a light source for illuminating the intersection and the reference image.

[0143] Example L: A method according to any of the preceding examples, wherein the aerosol generating article is cut through a hollow segment including the ventilation zone, and wherein checking for manufacturing defects includes checking whether at least one cross-sectional cut of the perforation extends from the inside of the hollow segment to the outside of the article, preferably wherein the number of cross-sectional cuts of the perforation extending from the inside of the hollow segment to the outside is determined.

[0144] Example M: ​​The method of the preceding example, wherein the article is rejected when at least one cross-sectional cut of the perforation does not extend from the interior to the exterior of the aerosol-generating article.

[0145] Example N: A method according to any of the preceding examples, wherein the aerosol generating article comprises a central longitudinal axis, and wherein the aerosol generating article is cut transversely to the longitudinal axis to produce the intersection, preferably wherein the aerosol generating article is cut perpendicular to the longitudinal axis.

[0146] Example O: The method of claim 14, wherein the plurality of perforations extend radially from the central longitudinal axis.

[0147] Example P: The method of any of the preceding examples, wherein the intersection is dyed to increase the contrast between the perforations and the wall of the aerosol-generating article.

[0148] Example Q: The method of any of the preceding examples, wherein the aerosol-generating article is tubular, and wherein the perforations are arranged circumferentially around the tubular aerosol-generating article.

[0149] Example R: An inspection tool for inspecting manufacturing defects in a ventilation region of an aerosol-generating article, the ventilation region comprising a plurality of perforations, the inspection tool comprising:

[0150] - a cavity for receiving the aerosol-generating article, wherein the aerosol-generating article is cut along a plane passing through the ventilation zone to create an intersection passing through the plurality of perforations,

[0151] - a reference image of a cross-sectional cut of the perforation, and

[0152] - means for rotating the reference image and the cut aerosol-generating article relative to each other for superimposing the reference image on the perforated cross-sectional cut in the intersection.

[0153] Example S: The inspection tool of the preceding example, wherein the inspection tool further comprises a light source for illuminating the intersection and the reference image.

[0154] Example T: The inspection tool of any preceding example R or S, wherein the reference image is included in a transparent rotatable portion of the tool.

[0155] Features described with respect to one embodiment may be equally applicable to other embodiments of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0156] The present invention will be further described, by way of example only, with reference to the accompanying drawings, in which:

[0157] Figure 1 shows a cross-sectional view of an aerosol-generating article including a ventilation zone;

[0158] Figure 2 depicts a schematic perspective view of an inspection tool housing a cut piece of an aerosol-generating article having an intersection;

[0159] Figure 3A shows a cross-sectional view of an aerosol-generating article having different perforations;

[0160] Figure 3B Shown with full cross-sectional cutouts and partial cross-sectional cutouts Figure 3A a cross-sectional view of an aerosol-generating article;

[0161] Figure 4A and 4B shows an enlarged view of an intersection of a cut piece of an aerosol-generating article, which also depicts a line as a reference image for inspecting the intersection for manufacturing defects;

[0162] Figure 5A and 5B showing an enlarged view of an intersection of a cut piece of an aerosol-generating article, which also includes an arc as a reference image for inspecting the intersection for manufacturing defects; and

[0163] Figure 6 An intersection of a cut piece of an aerosol-generating article is shown, with a reference image as outlined superimposed on a perforated cross-sectional cut in order to determine the percentage overlap between the area of ​​the reference image and the area of ​​the cross-sectional cut.

[0164] Figures 7A to 7C A sequence for cutting a ventilation zone of an aerosol-generating article using a tubular sacrificial element is shown.

[0165] In all the following drawings, the same elements are denoted by the same reference numerals. DETAILED DESCRIPTION

[0166] Figure 1 A cross-sectional view of an aerosol generating article 10 is shown. The aerosol generating article 10 comprises an aerosol forming substrate 22 having a susceptor element 24. Such an aerosol generating article 10 can be inserted into an aerosol generating device comprising, for example, a heating coil as a heating element. This heating coil can heat the susceptor element by induction heating via a changing magnetic field. The aerosol generating article 10 also comprises an aerosol cooling element 17 comprising hollow tubular elements 34 and 20. This aerosol cooling element 17 is used to cool and further promote the formation of an aerosol from the aerosol forming substrate. This aerosol cooling element 17 also comprises a ventilation area 14 having perforations 12. The perforations are often formed in the aerosol generating article by a laser device. When a user draws on the mouthpiece filter 30 of the aerosol generating article 10, ambient air from the outside of the article can enter the aerosol cooling element 17 through the perforations 12 into the interior of the article. This can promote the cooling and formation of the aerosol. The position of the perforations 12 within the ventilation zone 14 is important for providing an adequate cooling effect and promoting the formation of an aerosol. Therefore, regular inspection of the correct position and shape of the perforations within the ventilation zone 14 is important for providing a reliable smoking experience to the user. The aerosol generating article 10 also includes a front rod 32. There is an outer wrapper 26 that defines an aerosol-forming matrix in the upstream portion of the aerosol generating article. The downstream portion of the aerosol generating article including the ventilation zone 14 and the mouthpiece filter 30 is covered by a plugging paper 28. The aerosol generating article has a tubular shape and includes a central longitudinal axis 18. The ventilation zone 14 including the perforations can be cut along a plane 16. This plane 16 preferably extends perpendicular to the central longitudinal axis 18 of the aerosol generating article. Cutting the ventilation zone 14 along the plane 16 produces a cross-sectional cut of the perforations in the intersection, and the intersection can also be checked for manufacturing defects.

[0167] Figure 2 A schematic perspective view of an inspection tool 40 is shown, comprising a cut piece 10A of an aerosol-generating article within its cavity 38. Figure 116, thus providing a cut piece 10A of an aerosol-generating article comprising an intersection 36 passing through the ventilation zone. The inspection tool 40 comprises a magnifying device 42, such as a magnifying lens, which produces an enlarged view 44 of the intersection 36 of the cut piece of the aerosol-generating article. Inspecting the enlarged view 44 for the presence of manufacturing defects greatly facilitates the detection of defects. The magnifying device 42 also comprises a reference image 46 in the form of a line. This reference image 46 indicates the correct position and shape of the cross-sectional cut of the perforation. In addition, the area of ​​the reference image 46 within the thin hollow acetate tube 20 can also indicate the area of ​​the cross-sectional cut of the perforation that is correctly oriented and correctly formed. The magnifying device can be rotated around the central longitudinal axis 18 of the cut piece 10A of the aerosol-generating article, as indicated by arrow 48. This allows the user of the inspection tool 40 to superimpose the reference image 46 on each cross-sectional cut 12A of the enlarged view 44 of the intersection 36. The material of the thin hollow acetate tube 20 may be dyed with a dye, such as ink, to increase the contrast between the cellulose acetate material of the thin hollow acetate tube 20 and the cross-sectional cut 12A. The reference image 46 may be superimposed on the continuous cross-sectional cut 12A by rotating the magnifying device. This may allow a user to visually inspect at least some or all of the cross-sectional cuts 12A for manufacturing defects. There may be a light source 50 for illuminating the intersection or the magnified view 44 of the intersection. This may facilitate visual inspection for manufacturing defects.

[0168] Figure 3A A cross-sectional view of a portion of an aerosol generating article 10 is depicted in which a thin hollow acetate tube material 20 is in a ventilation zone. There are two separate perforations 12 in the ventilation zone. The perforation 12 on the left hand side of the thin hollow acetate tube 20 is a perforation of the correct shape and positioning, which is also correctly positioned within the plane 16. In contrast, the perforation 12' on the right hand side of the thin hollow acetate tube 20 exhibits an inclination relative to the plane 16. The perforation 12' exhibits an inclination as shown by the inclination angle 12D of the central axis 12C of the perforation relative to the plane 16 used to cut the article. This inclination causes the air to enter the interior of the aerosol generating article at a more downstream position of the aerosol cooling element of the article than the air enters the interior of the article through the perforation 12. This can adversely affect the cooling and formation of the aerosol. Therefore, the formation of such perforations 12' having a large inclination relative to the plane 16 should be avoided.

[0169] Figure 3B Depicted Figure 3A The aerosol generating article 10 shown in FIG. 1 is a cross-sectional view along plane 16. Figure 3A The aerosol generating article 10 provides Figure 3B The intersection 36 of the article shown in FIG. The correctly positioned and shaped Figure 3AThe perforations 16 in the Figure 3B The cross-sectional cut 12A shown in FIG. 1 is a complete cross-sectional cut extending from the exterior 13 of the aerosol generating article to the hollow interior 15. In contrast, the cross-sectional cut 12A shown in FIG. 1 is a complete cross-sectional cut extending from the exterior 13 of the aerosol generating article to the hollow interior 15. Figure 3A The perforations 12' shown in Fig. 1 provide partial cross-sectional cuts 12B after cutting that do not extend from the exterior to the interior of the aerosol-generating article. Thus, cutting the aerosol-generating article 10 along the plane 16 and through the perforations 12, 12' in the ventilation zone also provides information about the potential tilt of these perforations 12, 12' relative to the plane 16 and allows identification of perforations 12' that exhibit an undesirable tilt relative to the plane 16. Identification of these perforations 12' that exhibit an undesirably large tilt does not require the use of the reference images described herein.

[0170] Figure 4A An enlarged view 44 of the intersection 36 through the ventilation zone of the aerosol generating article is depicted, wherein the cellulose acetate material of the thin hollow acetate tube has been dyed with ink to increase contrast. The perforations in the ventilation zone create a complete cross-sectional cut 12A extending from the exterior of the article into the interior. A reference image 46 in the form of a line can be used to assess any potential manufacturing defects. This reference image 46 can be easily superimposed on the cross-sectional cut 12A, as shown in FIG. Figure 4A , indicating that the cross-sectional cut 12A has the desired correct positioning and shape. In addition, the cross-sectional cut 12A is a complete cross-sectional cut, thus also indicating that the corresponding perforations do not exhibit a significant inclination of the central axis of these perforations relative to the plane 16 used to cut the article. Aerosol-generating articles that exhibit such intersections can therefore pass methods for inspecting the ventilation zone for manufacturing defects, such as Figure 4A , as indicated by the check mark in the upper right corner of .

[0171] Figure 4B An enlarged view 44 of the intersection of the articles after cutting of the different aerosol generating articles is depicted. The intersection exhibits a partial cross-sectional cut 12B of the perforations, which indicates a significant inclination of the respective central axes of the perforations relative to the plane 16. In addition, as shown Figure 4B The positioning of the partial cross-sectional cut 12B shown within the circle depicted in FIG. 4 is also offset relative to the reference image 46. Therefore, it is not possible to superimpose a sufficiently large area of ​​the reference image 46 onto the area of ​​the cross-sectional cut. Therefore, in the method for inspecting for manufacturing defects, aerosol-generating articles that exhibit such an intersection after cutting are rejected, such as Figure 4B as indicated by the cross on the upper right side of .

[0172] Figure 5AAn enlarged view 44 of another intersection of the article after cutting the aerosol-generating article is shown. There is a reference image 46 in the form of an arc. This arc indicates the correct position of the cross-sectional cut within the intersection. In particular, the center axis 12E of the cross-sectional cut should be located within the arc so that the corresponding perforation passes the method for inspecting manufacturing defects. In Figure 5, the center axis 12E of one cross-sectional cut is completely located within the arc of the reference image, indicating that the corresponding perforation has the correct positioning and shape. In addition, there are many cross-sectional cuts 12A extending from the outside of the article into the inside, which also indicates that the corresponding perforations are correctly located within the plane 16 of the ventilation zone. Aerosol-generating articles exhibiting such an intersection can therefore pass the method for inspecting manufacturing defects of the ventilation zone, such as Figure 5A , as indicated by the check mark in the upper right corner of .

[0173] Figure 5B 4 shows an enlarged view of another intersection of the aerosol-generating article after cutting. In this case, the arc 46 does not cover the central axis 12E of the cross-sectional cut. On the contrary, there is an inclination angle or cutting angle 12F between the central axis 12E of the cross-sectional cut and the arc 46. If this inclination angle 12F is too large, in particular greater than 10 degrees, preferably greater than 5 degrees, the aerosol-generating article is rejected, as Figure 5B is indicated by the cross in the upper right corner of .

[0174] Figure 6 Another intersection of the ventilation zone of an aerosol generating article is shown. In this case, the perforations and their corresponding cross-sectional cuts 12A extend radially from the central longitudinal axis 18 of the article. Figure 6 12A so as to superimpose the area of ​​the reference image 46 onto the area of ​​the cross-sectional cut 12A. If the reference image 46 were a longer line that also extended into the interior of the intersection, only the area of ​​the reference image that is located within the cellulose acetate tube 20 would be considered when calculating the percentage of overlap between the area of ​​the reference image and the area of ​​the corresponding cross-sectional cut 12A, as shown in FIG. Figure 6 The cross-sectional cut is slightly tilted relative to the reference image, so that the entire area of ​​the reference image cannot be superimposed on the area of ​​the cross-sectional cut. However, small deviations of up to 20%, preferably up to 10%, as described above, may be tolerable. Figure 6 The aerosol generating device shown in the intersection may also be subjected to the method for inspecting manufacturing defects.

[0175] Figures 7A to 7C A sequence of method steps for cutting an aerosol-generating article along a plane 16 passing through the perforations 12 in a ventilation zone is depicted. Fig. 7A An aerosol generating article 10 having perforations 12 is schematically depicted. This article can be slid into (e.g. Figure 7B ). This tubular sacrificial element 52 may be, for example, a plastic tube that also includes an opening 54 that enables the tubular sacrificial element to be slid over the aerosol generating article 10. Subsequently, as Figure 7C As shown in , the ventilation area of ​​the article 10 can be cut along the plane 16 using the cutting device 56. This method allows the ventilation area to be easily cut through the perforations 12 without causing large deformation of the resulting intersection, which may interfere with the method for detecting manufacturing defects and should therefore be avoided.

Claims

1. A method for inspecting an aerosol-generating article having a ventilation zone for manufacturing defects, comprising: - providing an aerosol-generating article having a ventilation zone, the ventilation zone comprising a plurality of perforations, - cutting the aerosol-generating article along a plane passing through the plurality of perforations, thereby creating an intersection passing through the plurality of perforations, and - Checking the intersection for manufacturing defects.

2. The method according to claim 1, wherein at least one cross-sectional cut of the perforation within the intersection is checked for manufacturing defects, preferably wherein at least 2 or 3 cross-sectional cuts of the perforation are checked for manufacturing defects, and more preferably wherein all cross-sectional cuts of the perforation are checked for manufacturing defects.

3. Method according to the preceding claim, wherein the inclination of the cross-sectional cut of the perforation relative to the plane is determined.

4. A method according to any one of the preceding claims, wherein a reference image of a cross-sectional cut of a perforation is provided, and wherein the reference image is superimposed on the cross-sectional cut of the perforation in the intersection of the aerosol generating article for visual inspection of manufacturing defects, preferably wherein one or both of the width or orientation of the cross-sectional cut within the intersection are inspected by using the reference image, and more preferably wherein an area of ​​the reference image that can be superimposed on a cross-sectional cut of a perforation is determined.

5. The method according to the preceding claim, wherein the reference image is positioned above the intersection, and wherein the reference image and the intersection are arranged rotatably relative to each other, and wherein the reference image is superimposed on a cross-sectional cut of the perforation via the rotation.

6. A method according to any one of the preceding claims 4 or 5, wherein the aerosol generating article is rejected if less than 80%, preferably less than 90%, of the area of ​​the reference image can be superimposed on the area of ​​the cross-sectional cut of the perforation in the intersection of the aerosol generating article.

7. A method according to any one of the preceding claims 4 to 6, wherein the aerosol generating article is rejected if the central axis of the cross-sectional cut of the perforation in the intersection of the aerosol generating article has an inclination angle greater than 10 degrees, preferably greater than 5 degrees, relative to the reference image.

8. The method of claim 4, wherein the aerosol-generating article is rejected when the reference image cannot be superimposed on the cross-sectional cut of the perforation in the intersection.

9. The method according to any of the preceding claims 4 to 8, wherein the reference image comprises one of the following: - lines indicating the width and position of a correctly positioned and correctly formed cross-sectional cut, or - an arc of a circle indicating the area in which the central axis of the cross-sectional cut of the perforation should be located.

10. The method according to the preceding claims 4 to 9, wherein an inspection tool is used for inspecting manufacturing defects, the inspection tool comprising: - a cavity for receiving a cut piece of the aerosol-generating article, wherein the cut piece comprises the intersection, - said reference image of a cross-sectional cut of the perforation, and - means for rotating the reference image and the cut aerosol-generating article relative to each other for superimposing the reference image on the perforated cross-sectional cut in the intersection.

11. The method according to the preceding claim, wherein the inspection tool further comprises a light source for illuminating the intersection and the reference image.

12. A method according to any of the preceding claims, wherein the aerosol generating article is cut through a hollow segment including the ventilation zone, and wherein checking for manufacturing defects comprises checking whether at least one cross-sectional cut of the perforation extends from the inside of the hollow segment to the outside of the article, preferably wherein the number of cross-sectional cuts of the perforation extending from the inside of the hollow segment to the outside is determined.

13. A method according to the preceding claim, wherein the article is rejected when at least one cross-sectional cut of the perforation does not extend from the interior to the exterior of the aerosol-generating article.

14. A method according to any one of the preceding claims, wherein the aerosol generating article comprises a central longitudinal axis, and wherein the aerosol generating article is cut transversely to the longitudinal axis to produce the intersection, preferably wherein the aerosol generating article is cut perpendicular to the longitudinal axis.

15. An inspection tool for inspecting manufacturing defects in a ventilation region of an aerosol-generating article, the ventilation region comprising a plurality of perforations, the inspection tool comprising: - a cavity for receiving the aerosol-generating article, wherein the aerosol-generating article is cut along a plane passing through the ventilation zone to create an intersection passing through the plurality of perforations, - a reference image of a cross-sectional cut of the perforation, and - means for rotating the reference image and the cut aerosol-generating article relative to each other for superimposing the reference image on the perforated cross-sectional cut in the intersection.

Images