METHOD FOR EVALUATING AN AEROSOL-GENERATING ARTICLE WITH A SUSCEPTOR ELEMENT FOR MANUFACTURING DEFECTS

Abstract

The invention relates to a method for evaluating an aerosol-generating article with a susceptor element for manufacturing defects. The method comprises providing an aerosol-generating article with a substrate section, the substrate section comprising aerosol-forming substrate (24) and the susceptor element (26). The method furthermore comprises the method step of providing an intersection through the substrate section and the susceptor element. Another step includes evaluating the intersection for manufacturing defects by determining one or more of: positioning of the susceptor element in the substrate section, length of the cross section of the susceptor element, and shape of the cross section of the susceptor element. Therefor, in an embodiment a visual image of the intersection is divided into a plurality of segments (34), thereby creating an approximated circumference (22) of the cross-section with the susceptor element.

Claims

1-14. (canceled)

15. A method for evaluating an aerosol-generating article with a susceptor element for manufacturing defects, comprising: providing an aerosol-generating article with a substrate section, the substrate section comprising aerosol-forming substrate and a susceptor element, providing an intersection through the substrate section and the susceptor element, and evaluating the intersection for manufacturing defects by determining one or more of: positioning of the susceptor element in the substrate section, length of the cross section of the susceptor element, and shape of the cross section of the susceptor element, wherein a visual image of the intersection is recorded and wherein the image is evaluated for the manufacturing defects, wherein the visual image is divided into a plurality of segments and wherein a circumference of the cross section of the susceptor element is approximated by analyzing the segments in the visual image, thereby creating an approximated circumference of the cross section of the susceptor element.

16. The method according to claim 15, wherein a camera system is employed for recording an image of the intersection.

17. The method according to claim 15, wherein brightness changes are detected in the segments, thereby creating datapoints for the circumference of the cross section of the susceptor element, wherein the datapoints are employed to reconstruct the cross section of the susceptor element.

18. The method according to claim 15, wherein the approximated circumference in the substrate section is determined and compared to a reference range, thereby obtaining a first evaluation result.

19. The method according to claim 15, wherein the reference range comprises one or more of: a reference positioning of the cross section of the susceptor element within the aerosol-generating article, a reference shape of the cross section of the susceptor element, and a reference length of the cross section of the susceptor element and wherein one or more of the following method steps are preformed: comparing the reference positioning of the cross section of the susceptor element within the aerosol-generating article with the positioning of the approximated circumference of the cross section of the susceptor element, thereby obtaining a first positioning evaluation result, comparing the reference shape of the cross section of the susceptor element with the shape of the approximated circumference of the cross section of the susceptor element, thereby obtaining a first shape evaluation result, and comparing the reference length of the cross section of the susceptor element with the length of the approximated circumference of the cross section of the susceptor element, thereby obtaining a first length evaluation result.

20. The method according to claim 18, wherein the first evaluation result is obtained during manufacturing of the aerosol-generating article.

21. The method according to claim 15, wherein a circumference of the cross section of the susceptor element is determined by analyzing at least 70 percent of the image points of the visual image by fitting a cross sectional shape through the image points, thereby creating a refined circumference of the cross section of the susceptor element.

22. The method according to claim 18, wherein the refined circumference in the substrate section is compared to the reference range, thereby obtaining a second evaluation result.

23. The method according to claim 22, wherein the second evaluation result is obtained by employing a computer system.

24. The method according to claim 18, wherein an aerosol-generating article is rejected if: any part of the approximated circumference deviates from the reference positioning by more than 10 percent, or any part of the refined circumference deviates from the reference positioning by more than 10 percent.

25. The method according to claim 18, wherein the substrate section is covered with a wrapping paper and wherein: the first positioning evaluation result is obtained by determining a distance between the wrapping paper and the approximated circumference, or the second positioning evaluation result is obtained by determining a distance between the wrapping paper and the refined circumference.

26. The method according to claim 18, wherein the second evaluation result is employed for correcting the first evaluation result.

27. The method according to claim 22, wherein an aerosol-generating article is rejected if: any part of the approximated circumference deviates from the reference positioning by more than 10 percent, or any part of the refined circumference deviates from the reference positioning by more than 10 percent.

28. The method according to claim 22, wherein the substrate section is covered with a wrapping paper and wherein: the first positioning evaluation result is obtained by determining a distance between the wrapping paper and the approximated circumference, or the second positioning evaluation result is obtained by determining a distance between the wrapping paper and the refined circumference.

29. The method according to claim 22, wherein the second evaluation result is employed for correcting the first evaluation result.

30. The method according to claim 15, wherein a circumference of the cross section of the susceptor element is determined by analyzing all the image points of the visual image by fitting a cross sectional shape through the image points, thereby creating a refined circumference of the cross section of the susceptor element.

31. The method according to claim 15, wherein brightness changes are detected in the segments, thereby creating datapoints for the circumference of the cross section of the susceptor element, wherein the datapoints are employed to reconstruct the cross section of the susceptor element, wherein the cross section of the susceptor element is reconstructed by fitting a cross sectional shape through the datapoints of the segments.

32. The method according to claim 18, wherein the first evaluation result is obtained during manufacturing of the aerosol-generating article, wherein a production device is used for manufacturing of the aerosol-generating article and wherein said production device is employed for obtaining the first evaluation result.

33. The method according to claim 22, wherein the second evaluation result is obtained by employing a computer system, wherein the computer system is separate from the production device for manufacturing the aerosol-generating article.

Description

[0071] The invention will be further described, by way of example only, with reference to the accompanying drawings in which:

[0072] FIG. 1 shows a flow chart of one embodiment of the method of the invention for evaluating manufacturing defects;

[0073] FIG. 2 depicts an intersection of an article with a susceptor element and a reference range for the positioning of the susceptor element;

[0074] FIG. 3 shows another reference range for positioning of a cross-section of the susceptor element within the intersection of an aerosol-generating article;

[0075] FIG. 4 shows an intersection of an aerosol-generating article with a circumference of the cross section of the susceptor element which can either be obtained via a refined procedure or via approximation as disclosed herein;

[0076] FIG. 5 shows a parameter range for the shape of the cross-section of the susceptor element within the intersection of the article;

[0077] FIG. 6 shows the comparison of a reference positioning range and the reference shape range with an actual determined position and shape of a cross-section of a susceptor element;

[0078] FIG. 7 shows one example of an approximation procedure for obtaining the outer circumference of an aerosol-generating article by dividing a visual image into segments.

[0079] In the following the same elements are marked with the same reference numerals throughout all the figures.

[0080] FIG. 1 depicts a flow chart of one embodiment of the method of the invention for evaluating an aerosol-generating article with a susceptor element for manufacturing defects. The method employs reference range 10, the box titled product specification settings. This reference range 10 includes acceptable reference ranges for one or more of the positioning, shape and the length of a cross-section of the susceptor element within an aerosol-generating article. A camera system of the manufacturing device is able to record a visual image of the intersection of the aerosol-generating article with the susceptor as shown with the box with the reference numeral 18, titled IPC image. This camera might be a camera of the manufacturing device and might therefore be an internal process camera (IPC). The manufacturing device starts its own analysis of the visual image based on the operating software of the manufacturing device as shown in the box 20, titled in-line image analysis. This in-line image analysis enables to check the visual image, as denoted in the box with the reference numeral 16 to evaluate whether the metal susceptor (MS) is correctly positioned within the reference range in the aerosol-generating article as shown with the box 14 titled correct/non-correct MS centering. This results in a first evaluation result of the manufacturing device. For the first evaluation result approximation algorithms are employed in order to quickly evaluate the positioning of the susceptor element within the aerosol-generating article. Additionally, a computer system employs a more in-depth image processing procedure with the recorded visual image. This can be done by image processing procedures involving every image point of the visual image. This may provide a more refined and more accurate image processing of the visual image compared to the first evaluation result. This will provide further input into the image analysis and into the evaluation of the correct positioning of the susceptor element as shown in the flowchart with the arrow titled input of the off-line software.

[0081] FIG. 2 depicts a schematic intersection 30 of an aerosol-generating article. The intersection 30 shows the outer circumference 22 of the aerosol-generating article which may comprise wrapping paper. The wrapping paper is wrapped around aerosol-forming substrate 24. The aerosol-forming substrate 24 is located outside of an acceptable reference range for the positioning of the cross-section of the susceptor element, which is indicated by the box 28. The perfectly positioned cross-section 26 of the susceptor element is fully located within the acceptable reference range 28. The overall dimension of the cross-section of the aerosol-generating article may be a diameter of 7.05 (0.15) millimeters. The cross-section 26 of the susceptor might have a length of 4 (0.15) millimeters and a width of 0.06 (0.005) millimeters. The x-coordinates and the y-coordinates are indicated within FIG. 2. The acceptable reference range indicated by the area 28 may allow positioning of the perfectly positioned cross-section of the susceptor element within an area of the x-coordinate of the perfectly positioned susceptor element 3 millimeters and within an area of the y-coordinate of the perfectly positioned susceptor element 1 millimeters.

[0082] FIG. 3 shows an alternative reference range for the positioning of the cross-section of the susceptor element within the intersection of an aerosol-generating article. The reference range 28 includes the complete intersection of the aerosol-generating article which is at least a certain distance spaced apart from the outer circumference 22 of the article. In the present case the reference range 28 could include the complete area of the intersection 30 of the aerosol-generating article which is at least 1 millimeter spaced apart from the outer circumference 22.

[0083] FIG. 4 shows a circumference of a cross-section of a susceptor element which is either approximated or refined as described herein. The actual cross-section of the susceptor element is denoted with the reference numeral 26 and the dashed line 27 indicates the circumference of the cross-section of the susceptor element as determined via image processing. Evaluating the positioning of the circumference 27 of the susceptor element within the intersection 30 of the aerosol-generating article may include determining a distance 29 from the edge of the circumference of the susceptor element to the outer circumference 22 of the aerosol-generating article.

[0084] FIG. 5 shows a reference range for the shape of a susceptor element. The left-hand part of FIG. 5 shows different shapes 26A to 26C of the cross-section of a susceptor element. The shape 26A of the cross-section of the susceptor element fully complies with the acceptable reference range 32 and is located in the center of this reference range. In contrast to that, the shapes 26B and 26C include one bend and two bends of the susceptor, respectively.

[0085] Nevertheless, both shapes 26B and 26C are still within the acceptable reference range 32 as shown on the left-hand side of FIG. 5. In particular, the acceptable reference range 32 may allow bending of the plane of the cross-section of the susceptor element of 0.9 millimeters with regard to the plane of the fully compliant susceptor element with the shape 26A. The right-hand part of FIG. 5 shows the intersection 30 with the cross-section 26 of the susceptor element.

[0086] FIG. 6 depicts a comparison of the reference positioning range 28 and the reference shape range indicated by the dashed line 32 with a cross-section 26 of a susceptor element within an intersection 30 of an aerosol-generating article. It can be seen that the cross-section 26 of the susceptor element is fully located within the reference positioning range 28. Thus, the actually determined cross-section 26 of the susceptor element is able to pass the evaluation concerning the positioning of the susceptor element. However, as indicated by the dashed box 32, the heavily bent cross-section 26 of the susceptor element is partly located outside of the acceptable reference range 32 for the shape of the susceptor element. Consequently, this aerosol-generating article does not pass the evaluation test concerning the acceptable shape of the susceptor element within the intersection 30.

[0087] FIG. 7 shows one example of an image processing by approximation. A visual image of an intersection 30 of an aerosol-generating article is shown with an outer circumference 22 of the aerosol-generating article made of wrapping paper. In this example, the approximated outer circumference of the article is determined by dividing the visual image into segments 34. Each segment is then scanned from the periphery of the image to the center of the visual image for changes in the brightness of the segment. Any changes in the brightness of the segment may indicate a boundary of an object, in the present case the outer circumference of the aerosol-generating article. For each segment 34 where such a rapid change in the brightness can be detected, one image point 34A is generated at the position of the brightness change. An approximated circumference of the outer circumference 22 of the aerosol-generating article is then generated via fitting a curve through these various image points 34A for example by a least-squares method.