Abstract
The invention relates to a method for checking an aerosol-generating article with a ventilation zone for manufacturing defects. comprising: -providing an aerosol-generating article with a ventilation zone, the ventilation zone comprising a plurality of perforations, -cutting the aerosol-generating article along a plane through the plurality of perforations, thereby creating an intersection through the plurality of perforations, and -checking the intersection for manufacturing defects. Such a method for checking an aerosol-generating article for manufacturing defects can also check for the shape and the positioning of the perforations inside the article.
Claims
1. A method for checking an aerosol-generating article with a ventilation zone for manufacturing defects, comprising: providing an aerosol-generating article with a ventilation zone, the ventilation zone comprising a plurality of perforations, cutting the aerosol-generating article along a plane through the plurality of perforations, thereby creating an intersection through the plurality of perforations, and checking the intersection for manufacturing defects, wherein a reference image of a cross-sectional cut of a perforation is provided and wherein the reference image is superimposed on a cross-sectional cut of a perforation in the intersection of the aerosol-generating article in order to visually check for manufacturing defects.
2. The method according to claim 1, wherein at least one cross-sectional cut of a perforation within the intersection is checked for manufacturing defects.
3. The method according to claim 1 wherein an inclination of the cross-sectional cut of a perforation relative to the plane is determined.
4. The method according to claim 1, wherein one or both of a width or orientation of the cross-sectional cut within the intersection is checked by using the reference image.
5. The method according to claim 1, 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 one cross-sectional cut of a perforation via a rotation.
6. The method according to claim 1, wherein an aerosol-generating article is rejected if less than 80 percent of an area of the reference image can be superimposed on an area of a cross-sectional cut of a perforation in the intersection of the aerosol-generating article.
7. The method according to claim 1, wherein an aerosol-generating article is rejected if a central axis of a cross-sectional cut of a perforation in the intersection of the aerosol-generating article has an inclination angle of more than 10 degrees with respect to the reference image.
8. The method according to claim 1, wherein an aerosol-generating article is rejected when the reference image cannot be superimposed on the cross-sectional cut of a perforation in the intersection.
9. The method according to claim 1, wherein the reference image comprises one of: a line indicating a width and position of a correctly positioned and correctly shaped cross-sectional cut or, a circular arc, indicating an area within which a central axis of the cross-sectional cut of a perforation should be located.
10. The method according to claim 1, wherein an inspection tool is used for checking for manufacturing defects, the inspection tool comprising: a cavity for receiving a cut piece of the aerosol-generating article, wherein the cut piece includes the intersection, the reference image of a cross-sectional cut of a perforation, and means to rotate the reference image and the cut aerosol-generating article relative to each other for superimposing the reference image on a cross-sectional cut of a perforation within the intersection.
11. The method according to claim 10, wherein the inspection tool further comprises a light source for illuminating the intersection and the reference image.
12. The method according to claim 1, 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 a perforation extends from an interior of the hollow segment to an exterior of the article, and wherein the number of cross-sectional cuts of a perforation extending from the interior of the hollow segment to the exterior is determined.
13. The method according to claim 12, wherein an aerosol-generating article is rejected when at least one cross-sectional cut of a perforation does not extend from the interior to the exterior of the article.
14. The method according claim 1, wherein the aerosol-generating article includes a central longitudinal axis and wherein the aerosol-generating article is cut transversely to the longitudinal axis thereby creating the intersection, and wherein the aerosol-generating article is cut perpendicular to the longitudinal axis.
15. Inspection tool for checking for manufacturing defects in a ventilation zone of an aerosol-generating article, the ventilation zone 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 through the ventilation zone for creating an intersection through the plurality of perforations, a reference image of a cross-sectional cut of a perforation, and means to rotate the reference image and the cut-aerosol-generating article relative to each other for superimposing the reference image on a cross-sectional cut of a perforation within the intersection.
16. The method according to claim 1, wherein at least 2 or 3 cross-sectional cuts of a perforation within the intersection are checked for manufacturing defects.
17. The method according to claim 1, wherein all cross-sectional cuts of a perforation within the intersection are checked for manufacturing defects.
18. The method according to claim 1, wherein one or both of a width or orientation of the cross-sectional cut within the intersection is checked by using the reference image, and wherein an area of the reference image which can be superimposed on one cross-sectional cut of a perforation is determined.
19. The method according to claim 1, wherein an aerosol-generating article is rejected if less than 90 percent of an area of the reference image can be superimposed on the area of a cross-sectional cut of a perforation in the intersection of the aerosol-generating article.
20. The method according to claim 1, wherein an aerosol-generating article is rejected if a central axis of a cross-sectional cut of a perforation in the intersection of the aerosol-generating article has an inclination angle of more than 5 degrees with respect to the reference image.
Description
[0156] The invention will be further described, by way of example only, with reference to the accompanying drawings in which:
[0157] FIG. 1 shows a cross-sectional view of an aerosol-generating article including a ventilation zone;
[0158] FIG. 2 depicts a schematic perspective view of an inspection tool accommodating a cut piece of an aerosol-generating article with an intersection;
[0159] FIG. 3A shows a cross-sectional view of an aerosol-generating article with different perforations;
[0160] FIG. 3B shows a cross-sectional view of the aerosol-generating article of FIG. 3A with a complete cross-sectional cut and partial cross-sectional cut;
[0161] FIG. 4A and 4B show enlarged views of intersections of cut pieces of aerosol-generating articles also depicting a line as a reference image for checking the intersections for manufacturing defects;
[0162] FIG. 5A and 5B show enlarged views of intersections of cut pieces of aerosol-generating articles also including a circular arc as a reference image for checking the intersections for manufacturing defects; and
[0163] FIG. 6 shows an intersection of a cut piece of an aerosol-generating article wherein a reference image as outlined is superimposed over a cross-sectional cut for perforation in order to determine the percentage of overlap between the area of the reference image and the area of the cross-sectional cut.
[0164] FIG. 7A to 7C show sequence of cutting the ventilation zone of an aerosol-generating article employing a tubular sacrificial element.
[0165] In the following the same elements are marked with the same reference numerals throughout all the figures.
[0166] FIG. 1 shows a cross-sectional view of an aerosol-generating article 10. The aerosol-generating article 10 includes an aerosol-forming substrate 22 with a susceptor element 24. Such an aerosol-generating article 10 can be inserted into an aerosol-generating device including for example a heating coil as a heating element. This heating coil may heat the susceptor element via a varying magnetic field by inductive heating. The aerosol-generating article 10 also includes a hollow aerosol-cooling element 17 which comprises hollow tubular elements 34 and 20. This aerosol-cooling element 17 serves to cool down and to further promote the formation of an aerosol from the aerosol-forming substrate. This aerosol-cooling element 17 also includes a ventilation zone 14 with perforations 12. The perforations are frequently formed in the aerosol-generating article by a laser device. When a user sucks on the mouthpiece filter 30 of the aerosol-generating article 10, ambient air from the exterior of the article may enter the aerosol-cooling element 17 through the perforations 12 into the interior of the article. This may facilitate the cooling and the formation of the aerosol. The positions of the perforations 12 within the ventilation zone 14 are important for providing a sufficient cooling effect also facilitating the formation of an aerosol. Therefore, regularly checking the correct position and the shape of the perforations within the ventilation zone 14 is important for providing a reliable smoking experience to a user. The aerosol-generating article 10 also includes a front plug 32. Outer wrapping paper 26 is present circumscribing the aerosol-forming substrate 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 tipping 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 the plane 16. This plane 16 preferably runs perpendicular to the central longitudinal axis 18 of the aerosol-generating article. Cutting the ventilation zone 14 along the plane 16 produces cross-sectional cuts of the perforations within an intersection, which can be further checked for manufacturing defects.
[0167] FIG. 2 shows a schematic perspective view of an inspection tool 40 which includes a cut piece 10A of an aerosol-generating article within its cavity 38. Owing to the cutting of the ventilation zone along the plane 16 shown in FIG. 1, a cut piece 10A of an aerosol-generating article has been provided, which includes an intersection 36 through the ventilation zone. The inspection tool 40 includes magnifying means 42, for example a magnifying lens, which produces an enlarged view 44 of the intersection 36 of the cut piece of the aerosol-generating article. Checking the enlarged view 44 for manufacturing defects greatly facilitates the detection of the defects. The magnifying means 42 also includes a reference image 46 in the form of a line. This reference image 46 indicates the correct position and shape of cross-sectional cuts of perforations. Additionally, the area of the reference image 46 within the fine hollow acetate tube 20 also might indicate the area of a cross-sectional cut of a correctly orientated and correctly shaped perforation. The magnifying means can be rotated about the central longitudinal axis 18 of the cut piece 10A of the aerosol-generating article, as indicated by the arrow 48. This allows a user of the inspection tool 40 to superimpose the reference image 46 onto the various cross-sectional cuts 12A of the enlarged view 44 of the intersection 36. The material of the fine hollow acetate tube 20 might be stained with a dye, such as ink in order to increase the contrast between the cellulose acetate material of the fine hollow acetate tube 20 and the cross-sectional cuts 12A. The reference image 46 may be superimposed on successive cross-sectional cuts 12A by rotating the magnifying means. This may allow a user to visually inspect at least some or all of the cross-sectional cuts 12A for manufacturing defects. A light source 50 for illuminating the intersection or the enlarged view 44 of the intersection may be present. This may ease the visual inspection for manufacturing defects.
[0168] FIG. 3A depicts a cross-sectional view of a part of an aerosol-generating article 10 with the fine hollow acetate tube material 20 in the ventilation zone. Two separate perforations 12 are present in the ventilation zone. The perforation 12 on the left-hand side of the fine hollow acetate tube 20 is a perforation with the correct shape and positioning which is also correctly positioned within the pane 16. In contrast to that, the perforation 12 on the right-hand side of the fine hollow acetate tube 20 exhibits an inclination with regard 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 with regard to the plane 16 for cutting the article. This inclination results in air entering the interior of the aerosol-generating article at a more downstream position of the aerosol-cooling element of the article in comparison to air entering the interior of the article through the perforation 12. This may negatively affect the cooling and the formation of an aerosol. The formation of such a perforation 12 with a large inclination in comparison to the plane 16 therefore should be avoided.
[0169] FIG. 3B depicts a cross-sectional view of the aerosol-generating article 10 shown in FIG. 3A along the plane 16. Cutting the aerosol-generating article 10 of FIG. 3A along the plane 16 provides the intersection 36 of the article shown in FIG. 3B. The perforation 16 in FIG. 3A with the correct positioning and shape, whose central axis coincides with the plane 16 provides a cross-sectional cut 12A shown in FIG. 3B, which is a complete cross-sectional cut extending from the exterior 13 of the aerosol-generating article to the hollow interior 15. In contrast to that the perforation 12 shown in FIG. 3A having an inclination with regard to the plane 16 provides after cutting partial cross-sectional cut 12B which does not extend from the exterior to the interior of the aerosol-generating article. Cutting the aerosol-generating article 10 along the plane 16 in the ventilation zone and through the perforations 12, 12 therefore also provides information about a potential inclination of these perforations 12, 12 relative to the plane 16 and allows to identify perforations 12 exhibiting an unwanted inclination relative to the plane 16. Identifying these perforations 12 exhibiting an unwanted large inclination does not require the use of the reference image described herein.
[0170] FIG. 4A depicts an enlarged view 44 of an intersection 36 through the ventilation zone of an aerosol-generating article, wherein the cellulose acetate material of the fine hollow acetate tube has been stained with an ink in order to increase the contrast. The perforations in the ventilation zones result in complete cross-sectional cuts 12A which extend from the exterior of the article into the interior. A reference image 46 in the form of a line can be used for assessing any potential manufacturing defects. This reference image 46 can easily be superimposed on the cross-sectional cuts 12A as shown in FIG. 4A indicating that the cross-sectional cuts 12A have the desired correct positioning and shape. Additionally, the cross-sectional cuts 12A are complete cross-sectional cuts therefore also indicating that the respective perforations to not exhibit a significant inclination of the central axis of these perforations with regard to the plane 16 for cutting the article. An aerosol-generating article exhibiting such an intersection therefore can pass the method for checking the ventilation zone for manufacturing defects as indicated by the checkmark in the upper right-hand side of FIG. 4A
[0171] FIG. 4B depicts an enlarged view 44 of an intersection of a different aerosol-generating article after cutting the article. The intersection exhibits partial cross-sectional cuts 12B of the perforations indicating a significant inclination of the respective central axis of the perforations with regard to the plane 16. Additionally, the positioning of the partial cross-sectional cuts 12B with regard to the reference image 46 as shown within the circle depicted in FIG. 4B also is offset. Therefore, it is not possible to superimpose a large enough area of the reference image 46 onto the area of the cross-sectional cuts. Consequently, an aerosol-generating article exhibiting such an intersection after cutting is rejected in the method for checking for manufacturing defects, as indicated by the cross mark in the upper right-hand side of FIG. 4B.
[0172] FIG. 5A shows an enlarged view 44 of another intersection of an aerosol-generating article after cutting the article. A reference image 46 in the form of a circular arc is present. This circular arc indicates a correct position of a cross-sectional cut within the intersection. In particular, a central axis 12E of the cross-sectional cut should be located within the circular arc in order for the respective perforations to pass the method for checking for manufacturing defects. In FIG. 5 a central axis 12E of one cross-sectional cut is fully located within the circular arc of the reference image, indicating that the respective perforation has the correct positioning and shape. Additionally, numerous cross-sectional cuts 12A are present extending from the exterior of the article into the interior also indicating that the respective perforations are correctly located within the plane 16 of the ventilation zone. An aerosol-generating article exhibiting such an intersection therefore can pass the method for checking the ventilation zone for manufacturing defects as indicated by the checkmark in the upper right-hand side of FIG. 5A.
[0173] FIG. 5B shows an enlarged view of a further intersection of an aerosol-generating article after cutting the article. In this case the circular arc 46 does not cover the central axis 12E of the cross-sectional cut. Rather, and inclination angle or cutting angle 12F is present between the central axis 12E of the cross-sectional cut and the circular arc 46. If this inclination angle 12F is too large, in particular larger than 10 degrees, preferably larger than 5 degrees, then the aerosol-generating article is rejected as indicated by the cross mark in the upper right-hand side of FIG. 5B.
[0174] FIG. 6 shows another intersection of the ventilation zone of an aerosol-generating article. In this case, the perforations and also their respective cross-sectional cuts 12A are extending radially from the central longitudinal axis 18 of the article. A reference image 46 in the form of a line as indicated by the dashed line in FIG. 6 can be used in order to superimpose the area of the reference image 46 onto the area of a cross-sectional cut 12A. If the reference image 46 is a longer line also extending into the interior of the intersection, then only the area of the reference image located within the cellulose acetate tube 20 is taken into consideration when calculating the percentage of overlap between the area of the reference image and the area of the respective cross-sectional 12A as shown in FIG. 6. The cross-sectional cut is slightly tilted with regard to the reference image, so that not the complete area of the reference image can be superimposed on the area of the cross-sectional cut. However, small deviations of at a maximum 20 percent, preferably at a maximum of 10 percent as explained above, may be tolerable. Therefore, an aerosol-generating device exhibiting an intersection as shown in FIG. 6 can also pass the method for checking for manufacturing defects.
[0175] FIG. 7A to 7C depict a sequence of methods steps for cutting the aerosol-generating article along a plane 16 through the perforations 12 in the ventilation zone. FIG. 7A depicts schematically the aerosol-generating article 10 with the perforations 12. This article can be slipped into a tubular sacrificial element 52 as shown in FIG. 7B. This tubular sacrificial element 52 may for example be a plastic tube which also includes an opening 54 which enables the tubular sacrificial element to be slipped over the aerosol-generating article 10. Subsequently, as shown in FIG. 7C, the ventilation zone of the article 10 can be cut along the plane 16 employing cutting means 56. This method allows an easy cutting of the ventilation zones through the perforations 12 without causing a large deformation of the resulting intersection, Such a deformation of the intersection may interfere with the method for checking for manufacturing defects and therefore should be avoided.
