AEROSOL-GENERATING DEVICE FOR USE WITH AN AEROSOL-GENERATING ARTICLE

Abstract

An aerosol-generating device for an aerosol-generating article is provided, the device including: a receiving chamber to removably receive the article and having an inner surface and a center axis, along which the inner surface includes first and second axial portions, and an intermediate axial portion between the first and the second axial portions, the first and the second axial portions including a plurality of first and second protrusions, respectively, to contact first and second support elements of the article, respectively, and to retain the article in the chamber, the pluralities extending in a direction towards the center axis beyond the intermediate axial portion, the intermediate axial portion having a length of at least 20% of an overall length of the inner surface or of the chamber in the direction of the center axis and to surround a substrate element of the article when the article is received in the chamber.

Claims

1.-15. (canceled)

16. An aerosol-generating device for an aerosol-generating article, the aerosol-generating device comprising: a receiving chamber configured to removably receive at least a portion of the aerosol-generating article, the receiving chamber having an inner surface and a center axis, wherein along the center axis the inner surface comprises a first axial portion, a second axial portion, and an intermediate axial portion located between the first axial portion and the second axial portion, wherein the first axial portion comprises a plurality of first protrusions and the second axial portion comprises a plurality of second protrusions, wherein the plurality of first protrusions and the plurality of second protrusions are configured to contact a first support element and a second support element of the aerosol-generating article, respectively, and to retain the aerosol-generating article in the receiving chamber, wherein the plurality of first protrusions and the plurality of second protrusions extend in a direction towards the center axis beyond the intermediate axial portion, wherein the intermediate axial portion has a length of at least 20% of an overall length of the inner surface or of the receiving chamber in the direction of the center axis and is configured to surround a substrate element of the aerosol-generating article when the aerosol-generating article is received in the receiving chamber.

17. The aerosol-generating device according to claim 16, wherein the intermediate axial portion is without any protrusions.

18. The aerosol-generating device according to claim 16, wherein at least one of the protrusions of the plurality of first protrusions or at least one of the protrusions of the plurality of second protrusions extends in a direction substantially along the center axis of the receiving chamber.

19. The aerosol-generating device according to claim 16, further comprising one or more end stops arranged at a distal end of the receiving chamber.

20. The aerosol-generating device according to claim 19, wherein the one or more end stops are configured to cause an increase of the resistance to draw of at most 50 percent as compared to the aerosol-generating device without any end stops.

21. The aerosol-generating device according to claim 19, wherein the one or more end stops cover at most 50 percent of a total cross-sectional area of all interstices defined in between neighboring first protrusions or in between neighboring second protrusions as seen in a plane perpendicular to the center axis.

22. The aerosol-generating device according to claim 19, wherein the one or more end stops are ring segments.

23. The aerosol-generating device according to claim 16, wherein at least one protrusion of the plurality of first protrusions or at least one protrusion of the plurality of second protrusions has a constant radial distance to the center axis over a respective length of the respective protrusion.

24. The aerosol-generating device according to claim 16, wherein the receiving chamber comprises a first part and a second part, wherein the second part is inserted into the first part, and wherein the second part is a sleeve comprising the second axial portion, whereas the first part comprises the first axial portion.

25. The aerosol-generating device according to claim 16, wherein the receiving chamber is a sleeve and is inserted into a main body of the aerosol-generating device.

26. The aerosol-generating device according to claim 16, wherein at least one of the plurality of first protrusions and the plurality of second protrusions is a rib extending in an axial direction with respect to the center axis.

27. The aerosol-generating device according to claim 16, wherein at least one of the plurality of first protrusions and the plurality of second protrusions is chamfered at at least one of a side facing an insertion opening of the receiving chamber and at an opposite side facing away from an insertion opening of the receiving chamber.

28. An aerosol-generating system, comprising: an aerosol-generating device according to claim 16; and an aerosol-generating article comprising an aerosol-forming substrate, wherein at least a portion of the aerosol-generating article is removably received or removably receivable in the receiving chamber of the aerosol-generating device.

29. The aerosol-generating system according to claim 28, wherein the aerosol-generating article further comprises at least a first support element, a second support element, and a substrate element comprising the aerosol-forming substrate and being located between the first support element and the second support element, and wherein upon receiving the aerosol-generating article in the receiving chamber the first support element is in contact with the first axial portion and the second support element is in contact with the second axial portion, and the substrate element is surrounded by the intermediate axial portion without being in contact with the intermediate axial portion.

Description

[0079] The invention will be further described, by way of example only, with reference to the accompanying drawings, in which:

[0080] FIG. 1 schematically illustrates an exemplary embodiment of an aerosol-generating device according to the present invention in a sectional view;

[0081] FIG. 2 schematically illustrates a receiving chamber module of the device according to FIG. 1 in a perspective view together with an aerosol-generating article introduced therein;

[0082] FIG. 3 schematically illustrates the receiving chamber module and the aerosol-generating article according to FIG. 2 in a perspective sectional view;

[0083] FIG. 4 schematically illustrates the receiving chamber module according to FIG. 2 without the aerosol-generating article;

[0084] FIG. 5 schematically illustrates a sectional view of the receiving chamber according to FIG. 2; and

[0085] FIG. 6 schematically illustrates a front view of the receiving chamber according to FIG. 4.

[0086] FIG. 1 schematically illustrates an exemplary embodiment of an aerosol-generating device 200 according to the present invention. The aerosol-generating device 200 has an elongated shape and comprises a main body 210 and a receiving chamber module 220. The chamber module 220 comprises a receiving chamber 1 for receiving at least a portion of an aerosol-generating article 2. The receiving chamber module 220 is inserted into a cavity 230 formed within a proximal portion 211 of the main body 210. Within a distal portion 212, the main body 210 comprises a power source 250 and a controller 260 for powering and controlling operation of the device 200. Together, the aerosol-generating device 200 and the aerosol-generating article 2 form an aerosol-generating system according to the present invention.

[0087] Within the proximal portion 211 of the main body 210 that forms the cavity 230, the aerosol-generating device 200 comprises an inductor 240. In the present embodiment, the inductor 240 is a helical coil arranged around the receiving chamber 1. The inductor 240 is part of an inductive heater that is powered and operated by the power source 250 and the controller 260. In use of the device, the inductor 240 generates an alternating electromagnetic field within the receiving chamber 1 to inductively heat an aerosol-forming substrate contained in the article 2, when the latter is received in the receiving chamber 1.

[0088] FIG. 2, FIG. 3 and FIG. 4 show different aspects of the receiving chamber module 220 with and without the aerosol-generating article 2. As can be seen, the receiving chamber module 220 is an elongated sleeve comprising an insertion opening 15 through which the aerosol-generating article 2 may be inserted at least partially into the receiving chamber 1. The insertion direction of the aerosol-generating article 2 substantially extends along a center axis 201 of the receiving chamber 1. The receiving chamber 1 is made of PEEK (polyether ether ketone). The receiving chamber 1 has a substantially cylindrical shape with a substantially circular cross-section having a diameter of about 15 millimeter.

[0089] Corresponding to the shape of the receiving chamber 1, the aerosol-generating article 2 also has a substantially cylindrical rod-shape. As shown in FIG. 1 and FIG. 3, the article 2 comprises five elements sequentially arranged along a length axis of the article 2: a first support element 25, a substrate element 24, a second support element 23 comprising a central air passage 26, a cooling element 22 and a filter element 21. The first support element 25 is arranged at a distal end of the article 2 and the filter element 21 is arranged at a proximal end of the article 2. Each of the aforementioned elements 21, 22, 23, 24, 25 is substantially cylindrical, all of them having the same outer cross-sectional shape. In addition, the elements are circumscribed by an outer wrapper such as to keep the elements together and to maintain the desired circular cross-sectional shape of the rod-shaped article 2. Preferably, the wrapper is made of paper. The first support element 25 is used to cover and protect the distal front end of the substrate element 24. The substrate element 24 comprise the at least one aerosol-forming substrate to be heated. In addition, the substrate element 24 further comprises a susceptor (not shown) which is in thermal contact with the aerosol-forming substrate. Upon activating the inductor 240, the susceptor is heated due to at least one of eddy currents or hysteresis losses induced by the electromagnetic field, depending on the electrical and magnetic properties of the susceptor material. The susceptor heats up until reaching a temperature sufficient to vaporize material from the aerosol-forming substrate. The released material may be entrained in an airflow passing through the article 2 from the first support element 25 through the substrate element 24, the second support element 23 and the cooling element 22 towards the filter element 21. Along this way, the vaporized material cools to form an aerosol before escaping through the filter element 21 at the proximal end of the article 2.

[0090] FIG. 5 illustrates further details of the receiving chamber module 220 and the receiving chamber 1, respectively. The receiving chamber 1 comprises an inner surface 16 which extends over the entire axial length of the receiving chamber 1. In the present embodiment, the axial length of the receiving chamber 1 is in range of 25 millimeter to 28 mm. Along the center axis 201 of the receiving chamber 1, the inner surface 16 comprises a first axial portion 11, a second axial 13 portion and an intermediate axial portion 12 located between the first axial portion 11 and the second axial portion 13. The length of the intermediate axial portion 12 is of about 33 percent (about one third) of the axial length of the receiving chamber 1. As can be further seen in FIG. 5, the receiving chamber module 220 or the receiving chamber 1, respectively, is a multi-part component comprising a first part 221 and a second part 222. The second part 222 is formed as a sleeve and inserted into the first part 221. The second part 222 may be attached to the first part 221 via a form-fit or in a positive-fit manner or a friction-fit or a snap-fit. The second part 221 comprises the second axial portion 13, whereas the first part comprises the intermediate axial portion 12 and the second axial portion 13. Such a modular configuration facilitates manufacturing, in particular manufacturing by injection molding.

[0091] The first axial portion 11 comprises a plurality of first protrusions 10, for example twelve first protrusions 10. Likewise, the second axial portion 13 comprises a plurality of second protrusions 17, for example twelve second protrusions 17. In contrast, the intermediate axial portion 12 does not comprise any protrusions, but is even. Accordingly, the plurality of first protrusions 10 and the plurality of second protrusions 17 extend beyond the intermediate axial portion 12 in a radial inward direction towards the center axis 201. Hence, when the article 2 is inserted into the receiving cavity 1, the article 2 is only in contact with the plurality of first protrusions 10 and the plurality of second protrusions 17. In contrast, as can be in particular seen in FIG. 1, the article 2 is not in contact with the intermediate axial portion 12 of the inner surface 16. As a result, the overall contact area between the article 2 and the inner surface 16 of the receiving chamber 1 is significantly reduced. Advantageously, this leads to an overall reduction of heat losses due to direct thermal conduction from the aerosol-generating article 2 to the inner surface 16. Furthermore, adverse moistening effects on the article due to condensate formation in the chamber 1 are reduced as well.

[0092] Notwithstanding the reduced contact area between the article 2 and the inner surface 16, the article 2 is still securely retained in the receiving chamber 1 by the first and second protrusions 10, 17. In the present embodiment, this applies all the more since, on the one hand, the arrangement and the dimensions of the first, the second and the intermediate axial portions 11, 12, 13 and, on the other hand, the arrangement and the dimensions of the first support element 25, the substrate element 24 and the second support element 23 are adapted to each other. As can be seen in FIG. 1 and FIG. 3, when the article 2 is received in the chamber 1, the first support element 25 is in contact with the first protrusions 10 of the first axial portion 11 and the second support element 23 is in contact with the second protrusions 17 of the second axial portion 13. In contrast, the substrate element 24 substantially is surrounded by the intermediate axial portion 12, however, without any contact thereto. Only at its very axial ends, the substrate element 24 is partially in contact with the first protrusions 10 of the first axial portion 11 and the second protrusions 17 of the second axial portion 13. Due to this specific configuration, the first and second protrusions 10, 17 of the first and the second axial portion 11, 13 substantially only engage with those portions of the article 2 which are most rigid and which tend to shrink least during use, that is, with the first and second support element 23, 25.

[0093] As mentioned above, the receiving chamber 1 has a substantially cylindrical shape which refers to a shape of the receiving chamber 1 when masking out the first and second protrusions 10 and 17. Hence, areas of the first axial portion 11, in particular areas between neighboring first protrusions 10, and areas of the second axial portion 13, in particular areas between neighboring second protrusions 17, as well as areas of the intermediate portion are arranged on a common cylindrical shell surface.

[0094] In the present embodiment, the first and the second protrusions are formed as ribs extending along a direction parallel to the center axis 201. The twelve ribs of each one of the first and second axial portions 11, 13 are symmetrically arranged around the center axis 201 and equally spaced to each other. The spacing between neighboring ribs is in a range of 1.3 millimeter to 1.5 millimeter. With regard to its length extension, each rib is chamfered or comprises a respective chamfer at both ends, that is, at a side facing the insertion opening 15 and at an opposite side facing away from the insertion opening 15. Advantageously, the chamfers facilitate insertion and removal of the aerosol-generating article 2 into and from the receiving chamber 1. Apart from that, each rib has a constant height extension along its length extension. In the present embodiment, the height is in range of 0.4 millimeter to 0.5 millimeter as measured in a radial direction towards the center axis 201.

[0095] As shown in FIG. 6, each rib has a substantially rectangular cross-sectional shape as seen in a plane perpendicular to the center axis 201. The edges 31 of each rib along its length extension are rounded in order to avoid slitting the wrapper of the aerosol-generating article 2 during insertion and removal of the article 2.

[0096] As can be further seen in FIG. 5, the first protrusions 10 of first axial portion 11 and the second protrusions 17 of the second axial portion 13 fall in line, that is, each of the first protrusions 10 is aligned with a respective one of the second protrusions 17 as seen in a direction parallel to the center axis 201. Due to this, the interstices 32 in between neighboring first protrusions 10 and in between neighboring second protrusions 17 advantageously form a multi-channel airflow passage (see dashed dotted arrows in FIG. 5) which extends form the insertion opening 15 at the proximal end 4 of the receiving chamber 1 to the bottom of the receiving chamber 1 at its distal end 5.

[0097] Accordingly, when a negative pressure is applied at the filter element 21 of an aerosol-generating article 2 received in the receiving chamber 1, for example, when a user takes a puff, air is drawn into the receiving chamber 1 at the rim of the insertion opening 15 and further along the multi-channel airflow passage into the bottom portion at the distal end 4 of the receiving chamber 1. There, the airflow enters the aerosol-generating article 2 through the first support element 25 and further passes through the substrate element 24, the second support element 23, the aerosol cooling element 22 and the filter element 21 where it finally exits the article 2. In the substrate element 24A, vaporized material from the aerosol-forming substrate is entrained into the airflow and subsequently cooled down on its further way through the second support element 23, the aerosol cooling element 22 and the filter element 21 such as to form an aerosol.

[0098] In order to enable a proper redirection of the airflow into the aerosol-generating article 2 at the bottom portion of the receiving chamber 1, the aerosol-generating device 200 according to the present embodiment comprises three end stops 14 which are arranged at the distal end 5 of the receiving chamber 1. The end stops 14 are configured to limit the insertion depth of the article 2 into the receiving chamber 1 and, thus, to prevent the article 2 from abutting the bottom surface of the receiving chamber 1. This is shown in FIG. 1.

[0099] As can be seen in FIG. 5, the three end stops 14 are formed as ring-segments which are symmetrically and equally spaced arranged around the center axis 201 at the inner circumference of the receiving chamber 1. Each ring segment 14 has a height dimension in the direction of the center axis 201 in a range of 1 millimeter to 3 millimeter, for example 1.4 millimeter, and a radial dimension in a range of 1 millimeter to 2 millimeter, for example 1.3 millimeter as measured in a radial direction towards the center axis 201.

[0100] As can be further seen in FIG. 5, the end stops 14 covers or blocks some of the channels of the airflow passage that is defined by the interstices 32 in between neighboring first protrusions 10 and neighboring second protrusions 17. As a result, the airflow passing in between the article 1, the plurality of first protrusions 10, the plurality of second protrusions 17 and the end stops 14 is reduced as compared to an airflow passing in between the article 2, the plurality of first protrusions 10 and the plurality of second protrusions 17 in absence of the end stops 14. As a consequence, the resistance to draw of the system is also increased as compared to a system without end stops. In use of the device, a resistance to draw may be in range of 70 mmWG to 120 mmWG. Preferably, a resistance to draw (RTD) may be between 40 mmWG and 70 mmWG, in particular 45 mmWG and 65 mmWG, for example 55 mmWG. To ensure a reasonable minimum airflow and a reasonable resistance to draw, the number, the shape and the dimensions of the end stops preferably is chosen such that the (reduced) airflow is at least 50 percent, in particular at least 60 percent, preferably at least 70 percent, even more preferably at least 80 percent of the airflow in absence of the end stops. This may be achieved by choosing the number, the shape and the dimensions of the end stops such that the end stops cover at most 50 percent, in particular at most 40 percent, preferably at most 30 percent, even more preferably at most 20 percent of a total cross-sectional area of all interstices 32 defined in between neighboring first protrusions 10 or in between neighboring second protrusions 17 as seen in a plane perpendicular to the center axis. In the present embodiment, the total cross-sectional area of all interstices 32 defined in between neighboring first protrusions 10 or in between neighboring second protrusions 17 is about 4.5 square millimeter when taking into account a coverage by the end stops 14, and about 7.2 square millimeter in absence of the end stops 14.