Abstract
An aerosol-generating article for an aerosol-generating device is provided, the article including: an open-ended hollow-cylindrical reservoir body including a tubular outer wall and an inner partition wall extending between two opposing inner portions of the outer wall so as to partition an inner void of the body into first and second compartments, which are laterally arranged adjacent to each other along a longitudinal axis of the body; a first end cap attached to a first end of the body that sealingly closes at least the first compartment at the first end; and a second end cap attached to a second end of the body that sealingly closes the first and the second compartments at the second end, the second end cap including a fluid passage providing a fluid communication between the first and the second compartments.
Claims
1.-15. (canceled)
16. An aerosol-generating article for an aerosol-generating device, the aerosol-generating article comprising: an open-ended hollow-cylindrical reservoir body comprising a tubular outer wall and an inner partition wall extending between two opposing inner portions of the tubular outer wall so as to partition an inner void of the open-ended hollow-cylindrical reservoir body into a first compartment and a second compartment, wherein the first compartment and the second compartment are laterally arranged adjacent to each other along a longitudinal axis of the open-ended hollow-cylindrical reservoir body; a first end cap attached to a first end of the open-ended hollow-cylindrical reservoir body that sealingly closes at least the first compartment at the first end of the open-ended hollow-cylindrical reservoir body; and a second end cap attached to a second end of the open-ended hollow-cylindrical reservoir body that sealingly closes the first compartment and the second compartment at the second end of the open-ended hollow-cylindrical reservoir body, wherein the second end cap comprises a fluid passage providing a fluid communication between the first compartment and the second compartment.
17. The aerosol-generating article according to claim 16, wherein the open-ended hollow-cylindrical reservoir body is an extruded body
18. The aerosol-generating article according to claim 16, wherein the open-ended hollow-cylindrical reservoir body is a one-piece extruded body.
19. The aerosol-generating article according to claim 16, wherein an arrangement of the inner partition wall within the tubular outer wall is asymmetric with respect to a cross-section of the open-ended hollow-cylindrical reservoir body perpendicular to the longitudinal axis of the open-ended hollow-cylindrical reservoir body.
20. The aerosol-generating article according to claim 16, wherein the first end cap comprises an outlet providing a fluid communication between the second compartment and an outside of the aerosol-generating article.
21. The aerosol-generating article according to claim 16, wherein the first end cap is formed as a mouthpiece.
22. The aerosol-generating article according to claim 16, wherein the first end cap and the second end cap are attached to the open-ended hollow-cylindrical reservoir body by at least one of a form fit, a force fit, or an adhesive bond.
23. The aerosol-generating article according to claim 16, wherein the second end cap further comprises a recess or a channel providing a fluid communication between the first compartment and the second compartment.
24. The aerosol-generating article according to claim 16, wherein a maximum dimension of the second compartment between two opposing portions of the inner partition wall and the tubular outer wall is in range between 0.2 millimeter and 5 millimeters.
25. The aerosol-generating article according to claim 16, wherein a maximum dimension of the second compartment between two opposing portions of the inner partition wall and the tubular outer wall is in range between 1 millimeter and 2.5 millimeters.
26. The aerosol-generating article according to claim 16, wherein a volume of the second compartment is at most 50 percent of a volume of the first compartment.
27. The aerosol-generating article according to claim 16, wherein a volume of the second compartment is at most 20 percent of a volume of the first compartment.
28. The aerosol-generating article according to claim 16, further comprising a bushing arranged within the second compartment transverse to the longitudinal axis of the open-ended hollow-cylindrical reservoir body, wherein the bushing partitions the second compartment into a vaporization zone and a buffer reservoir.
29. The aerosol-generating article according to claim 16, further comprising a bushing arranged within the second compartment perpendicular to the longitudinal axis of the open-ended hollow-cylindrical reservoir body, wherein the bushing partitions the second compartment into a vaporization zone and a buffer reservoir.
30. The aerosol-generating article according to claim 28, further comprising a liquid conduit passing through the bushing and being configured to deliver aerosol-forming liquid from the buffer reservoir to the vaporization zone.
31. The aerosol-generating article according to claim 30, wherein the liquid conduit is inductively heatable.
32. An aerosol-generating system comprising an aerosol-generating device and an aerosol-generating article according to claim 16 for the aerosol-generating device.
33. A method of manufacturing an aerosol-generating article according to claim 16, the method comprising: extruding the open-ended hollow-cylindrical reservoir body, wherein the open-ended hollow-cylindrical reservoir body has a fixed cross-sectional profile along the longitudinal axis of the open-ended hollow-cylindrical reservoir body; providing the first end cap and the second end cap; and attaching the first end cap to the first end of the open-ended hollow-cylindrical reservoir body and attaching the second end cap to the second end of the open-ended hollow-cylindrical reservoir body.
34. The method according to claim 33, further comprising filling an aerosol-forming liquid into the first compartment after attaching at least one of the first end cap to the first end of the open-ended hollow-cylindrical reservoir body or the second end cap to the second end of the open-ended hollow-cylindrical reservoir body, respectively.
Description
[0128] Examples will now be further described with reference to the figures in which:
[0129] FIG. 1 schematically illustrates a first embodiment of an aerosol-generating article according to the present invention;
[0130] FIG. 2 shows a cross-section through the aerosol-generating article according to FIG. 1 along line A-A;
[0131] FIG. 3 shows a cross-section through the aerosol-generating article according to FIG. 1 along line B-B;
[0132] FIG. 4 schematically illustrates an exemplary embodiment of an aerosol-generating system according to the present invention, comprising the article according to FIG. 1 and an aerosol-generating device for use with the article;
[0133] FIG. 5 shows a cross-section through an alternative embodiment of the aerosol-generating article according to FIG. 1;
[0134] FIG. 6 shows the aerosol-generating article similar to the article shown in FIG. 1, yet without a partition wall;
[0135] FIG. 7 shows the aerosol-generating article according to FIG. 1 in a substantially horizontal position;
[0136] FIG. 8 shows the aerosol-generating article according to FIG. 1 in an upside down position;
[0137] FIG. 9 schematically illustrates a second embodiment of an aerosol-generating article according to the present invention; and
[0138] FIG. 10 shows the aerosol-generating article according to FIG. 9 in an upside down position.
[0139] FIG. 1 schematically illustrates an aerosol-generating article 40 according to a first embodiment of the present invention. As will be described in more detail further below with regard to FIG. 4, the aerosol-generating article 40 is configured for use with an inductively heating aerosol-generating device in order to vaporize an aerosol-forming liquid 50 provided by the aerosol-generating article 40. The article 40 comprises a substantially cylindrical article housing made of a liquid impermeable rigid material, for example, one of PET (polyethylene terephthalate), PP (polypropylene) or PE (polyethylene). The article housing comprises a hollow-cylindrical outer tubular wall 42, a first end cap 44 and a second end cap 43. The article further comprises a partition wall 41, as part of the article housing, which partitions the inner void of the outer tubular wall 42 into a first compartment 58 and a second compartment 59. Together, the outer tubular wall 42 and the partition wall 41 form a reservoir body according to the present invention. The first compartment 58 and the second compartment 59 are laterally arranged adjacent to each other along the longitudinal axis of the reservoir body. The first compartment 58 serves as a main reservoir 51 for storing aerosol-forming liquid 50. Within the second compartment 59, the article 40 comprises a substantially disc-shaped bushing 45 at about half way of the length extension of the outer tubular wall 42 or the reservoir body, respectively. The bushing 45 separates the inner void of the second compartment into two portions, namely, a vaporization cavity 53 and a capillary buffer reservoir 52 for storing aerosol-forming liquid due to capillary action. This will be described in more detail further below. The first end cap 44 sealingly closes the reservoir body at a first end 57 of the reservoir body. At the opposite second end 56, the reservoir body is closed by the second end cap 43. The second end cap 43 comprises a fluid passage which provides a fluid communication between the first compartment 58 and the second compartment 59, and thus between the capillary buffer reservoir 52 and the main reservoir 51. The fluid passage is formed by a recess in the second end cap 43. As can be seen in FIG. 1, the recess is formed such that the main reservoir 51 directly opens out into the capillary buffer reservoir 52 allowing aerosol-forming liquid 50 to freely flow from the main reservoir 51 into the capillary buffer reservoir 52. To facilitate the fluid flow around the free end of the partition wall 41 facing the second end cap 43, the free end of the partition wall 41 comprises rounded edges.
[0140] As can be seen in FIG. 2 and FIG. 3, which show a cross-section through the aerosol-generating article according to FIG. 1 along line A-A and line B-B, respectively, the inner partition wall 41 is separate from the tubular outer wall 42. Preferably, the tubular outer wall 42 and the partition wall 41 are manufactured separately from each other by extrusion. Subsequently, the tubular outer wall 42 and the partition wall 41 may be assembled such as to form a reservoir body according to the present invention. As can be further seen in FIG. 2 and FIG. 3, the inner partition wall 41 is installed between two opposing inner portions of the tubular outer wall 42 parallel to a center axis of the tubular outer wall 42, yet asymmetrically such as to partition the inner void of the reservoir body into a first compartment 58 and a second compartment 59 which is smaller than the first compartment. In this configuration, the tubular outer wall 42 and the partition wall 41 may be attached to each other by an adhesive bond, for example, by welding or gluing. Advantageously, adhesive bond provides a sealing between the first compartment 58 and the second compartment 59, where the partition wall 41 and the tubular outer wall 42 come together.
[0141] Alternatively, as shown in FIG. 5, the inner partition wall 41 and the tubular outer wall 42 may be integral with other. In this configuration, the tubular outer wall 42 and the partition wall 41 may also manufactured together by extrusion, resulting in a one-piece extruded reservoir body. Advantageously, a one-piece extruded reservoir body is particularly easy and inexpensive to manufacture. Even more, a one-piece extruded reservoir body does not require a sealing between the first compartment 58 and the second compartment 59, where the partition wall 41 and the tubular outer wall 42 come together.
[0142] In general, the aerosol-generating article 40 may be an aerosol-generating article for single use or an aerosol-generating article for multiple uses. In the latter case, the aerosol-generating article 40 may be refillable. That is, the main reservoir 51 may be refillable with aerosol-forming liquid 50 after depletion.
[0143] The article 40 further comprises a liquid conduit 70 in fluid communication with the capillary buffer reservoir 52 for conveying aerosol-forming liquid 50 from the capillary buffer reservoir 52 into the vaporization cavity 53. As can be particularly seen in FIG. 2 and FIG. 3, the liquid conduit 70 according to the present embodiment is an unstranded filament bundle comprising a plurality of filaments 71, 72 arranged parallel to each other. Due to the arrangement of the filaments 71, 72 in the filament bundle and due to the small diameter of the filaments 71, 72, the liquid conduit 70 comprises capillary channels formed between the filaments 71, 72. These channels provide capillary action along the length extension of the liquid conduit 70, thus allowing for conveying aerosol-forming liquid 50 from the capillary buffer reservoir 52 into the vaporization cavity 53.
[0144] In addition to the liquid conveying property, the liquid conduit 70 of the present embodiment is also configured for inductive heating. For that purpose, the liquid conduit 70 comprises at least a plurality of first filaments 71 including a first susceptor material that is optimized with regard to heat generation. The liquid conduit 70 may also comprises a plurality of second filaments 72 including a second susceptor material which serves as temperature marker, as described further above. Due to the susceptive nature of the filament materials, the liquid conduit 70 is capable to be inductively heated in an alternating magnetic field and thus to vaporize aerosol-forming liquid in thermal contact with the filaments 71, 72. The liquid conduit 70 thus is capable to perform two functions: conveying and heating aerosol-forming liquid. For this reason, the liquid conduit may also be denoted as a liquid-conveying susceptor assembly.
[0145] As can be seen in FIG. 1, the liquid conduit 70 passes through an opening in the bushing 45 such that a first portion of the liquid conduit 70 is arranged in the buffer reservoir 52 and a second portion is arranged in the vaporization cavity 53. The opening through the bushing 45 serves not only as a feedthrough for the liquid conduit, but also for bundling the filaments 71, 72, that is, for keeping the filaments 71, 72 together. Furthermore, the opening serves to fix the position of the liquid conduit 70 relative to the article housing. As can be further seen in FIG. 2 and FIG. 3, the filament bundle of the liquid conduit 70 has a substantially circular cross-section which is particularly easy to manufacture.
[0146] As the first portion of the liquid conduit 70 is arranged in the buffer reservoir 52 and thus immersed in aerosol-forming liquid 50, it acts as a soaking section 75 for conveying aerosol-forming liquid 50 from the buffer reservoir 52 to the second portion of the liquid conduit 70. In the vaporization cavity 53, the second portion acts at least partially as a heating section 76 for vaporizing aerosol-forming liquid 50 when being exposed to an alternating magnetic field in order to inductively heat the filaments 71, 72. This will be described in more detail below with regard to FIG. 4.
[0147] As can be further seen in FIG. 1, the article 40 comprises at least one air inlet 46 through the reservoir body into the vaporization cavity 53 which enables air to enter the vaporization cavity 53. The air inlet 46 may be configured to provide airflow at or around the heating section 76 of the liquid conduit 70. The air inlet 46 may be a hole through the reservoir body. Likewise, the air inlet 46 may be a nozzle that is configured to direct airflow to a specific target location at the liquid conduit 70. In addition, the article 40 comprises a tapered shape mouthpiece 47 which is attached to the first end cap 44 and configured to be taken into a user's mouth for puffing. The mouthpiece 47 further includes a filter 55 and an air outlet 48. The mouthpiece 47 is in fluid communication with the vaporization cavity 53 through an outlet 49 in the first end cap 44. Hence, when a user takes a puff at the mouthpiece 47, air is drawn into the vaporization cavity 53 through the air inlet 46. From there, the air passes through the aperture 49 into the mouthpiece 47 and further through the filter 55 and the air outlet 48 into a users' mouth. In the vaporization cavity 53, aerosol-forming liquid vaporized from the heating section 76 of the liquid conduit 70 is exposed to the air passing through the article 40 such as to form an aerosol which may then be drawn out through the mouthpiece 47.
[0148] FIG. 4 schematically illustrates an aerosol-generating system 80 according to an exemplary embodiment of the present invention. The system 80 comprises an aerosol-generating article 40 as shown in FIG. 1-3 as well as an electrically operated aerosol-generating device 60 that is capable of interacting with the article 40 in order to generate an aerosol. For this, the aerosol-generating device 60 comprises a receiving cavity 62 formed within the device housing 61 at a proximal end of the device 60. The receiving cavity 62 is configured to removably receive at least a portion of the aerosol-generating article 40. In particular, the aerosol-generating device is configured to inductively heat the heating section 76 of the liquid conduit 70 in order to vaporize aerosol-forming liquid 50 that is conveyed from the capillary buffer reservoir 52 via the soaking section 75 to the heating section 76 in the vaporization cavity 53. For this, the aerosol-generating device 60 comprises an induction source including an induction coil 32. In the present embodiment, the induction coil 32 is a single helical coil which is arranged and configured to generate a substantially homogeneous alternating magnetic field within the receiving cavity 62. As can be seen in FIG. 4, the induction coil 32 is arranged around the proximal end portion of the receiving cavity 62 such as to only surround the heating section 76 of the liquid conduit 70 when the aerosol-generating article 40 is received in the receiving cavity 62. Accordingly, in use of the device 60, the induction coil 32 generates an alternating magnetic field that only penetrates the heating section 76 of the liquid conduit 70 in the vaporization cavity 53 of the article 40. In contrast, due to the local heating, the soaking section 75 of the liquid conduit 70 stays at temperatures below the vaporization temperature. Thus, boiling of aerosol-forming liquid 50 within the capillary buffer reservoir 52 and the main reservoir 51 is prevented. Hence, in use the liquid conduit 70 comprises a temperature profile along its length extension with sections of higher and lower temperatures. More specifically, the temperature profile shows a temperature increase from temperatures below a vaporization temperature T_vap of the aerosol-forming liquid 50 in the soaking section 75 to temperatures above the respective vaporization temperature in the heating section 76.
[0149] The actual temperature profile forming up in use of the susceptor assembly 10 depends on the thermal conductivity and the length of the liquid conduit 70. Accordingly, in order to have sufficient temperature gradient between the soaking sections 75 and the heating section 76, the liquid conduit 70 requires a certain total length. With regard to the present embodiment, the total length of the liquid conduit 70 may be in a range between 5 millimeter and 50 millimeter, in particular between 10 millimeter and 40 millimeter, preferably between 10 millimeter and 30 millimeter, more preferably between 10 millimeter and 20 millimeter.
[0150] The liquid conduit 70 is arranged off-center with regard to the geometrical center axis of the aerosol-generating article 40. Due to this, the liquid conduit 70 is arranged off-center with regard to the symmetry axis of the alternating magnetic field generated by the induction coil 32 when the article 40 is received in the cavity 62 of the device 60. Advantageously, due to the off-center arrangement, the liquid conduit 70 is arranged in a region of the alternating magnetic field having a higher field density as compared to a symmetric center arrangement. As a consequence, the heating efficiency is enhanced.
[0151] The aerosol-generating device 60 further comprises a controller 64 for controlling operation of the aerosol-generating system 80, in particular for controlling the heating operation. Furthermore, the aerosol-generating device 60 comprises a power supply 63 providing electrical power for generating the alternating magnetic field. Preferably, the power supply 63 is a battery such as a lithium iron phosphate battery. The power supply 63 may have a capacity that allows for the storage of enough energy for one or more user experiences. Both, the controller 64 and the power supply 63 arranged in a distal portion of the aerosol-generating device 60.
[0152] The function of the capillary buffer reservoir 52 will now be described in more detail with regard to FIG. 6, FIG. 7 and FIG. 8. FIG. 6 shows the aerosol-generating article 40 according to FIG. 1, yet without comprising a capillary buffer reservoir. Further in contrast to FIG. 1, FIG. 6 shows the article 40 in a substantially horizontal orientation. Due to the different orientation, the aerosol-forming liquid 50 in the article 40 is re-distributed in such a way that—depending on the fluid level—the liquid conduit 70 is not in contact with the aerosol-forming liquid 50 anymore. As a consequence, the delivery of aerosol-forming liquid to the vaporization zone 53 is interrupted which causes a rapid decrease or even outage of aerosol formation if the article was used in this orientation for a certain time. The purpose of the buffer reservoir 52 is to remedy this. Basically, the buffer reservoir 52 provides a small volume reservoir that is in fluid communication with the main reservoir 51 and the liquid conduit 70 and configured to trap a certain amount of aerosol-forming liquid due to capillary action independent of the article orientation. For this, at least one dimension of the capillary buffer reservoir 52 is chosen to be on the order of the effective capillary length, which typically is in the range of a few millimeters for most liquids. In the present embodiment, the capillary action of the buffer reservoir 52 is caused by the fact that the maximum distance D between opposing portions of the partition wall 41 and the inner surface of the tubular outer wall 42 is in a range of a few millimeters only, as indicated in FIG. 3 and FIG. 7. For example, the maximum distance D may be in a range between 1 millimeter and 5 millimeter. Due to this, capillary effects dominate over gravity in the capillary buffer reservoir 52. As a consequence, once aerosol-forming liquid 50 filled in the buffer reservoir 52, it is prevented from flowing back into the main reservoir 51 when the orientation of the article is changed, for example, when the article 40 is turned from a substantially upright position as shown in FIG. 1 into a substantially horizontal position as shown FIG. 7, or even into an upside down position as shown in FIG. 8. Hence, independent of the article orientation, the buffer reservoir 40 reliably traps the liquid aerosol-forming due to the capillary action of its small volume, similar to a buffer reservoir of a fountain pen. Yet, the capillary action along the liquid conduit is still large enough to convey the trapped liquid from the capillary buffer reservoir 52 to the vaporization zone. The volume of the buffer reservoir is chosen such as to provide sufficient liquid available for a few puffs, independent of the article orientation. Accordingly, the total volume of the capillary buffer reservoir 52 may be at least 5 cubic millimeters, in particular at least 10 cubic millimeters, preferably at least 15 cubic millimeters.
[0153] FIG. 9 and FIG. 10 schematically illustrate a second exemplary embodiment of an aerosol-generating 240 article according to the present invention. In general, the aerosol-generating article 240 according to FIGS. 9 and 10 is similar to the aerosol-generating article 40 shown in FIG. 1. Therefore, identical or similar features are denoted with the same reference signs, yet incremented by 200. In contrast to the article 40 shown in FIG. 1, the article 240 according to FIGS. 9 and 10 comprises a liquid conduit 270, a buffer reservoir 252 and a vaporization zone 253 which are arranged symmetrically with regard to the geometrical center axis of the 40. For this, a cylindrical partition wall 241 is arranged coaxially in a cylindrical tubular outer wall 242 such as to partition the inner void of the cylindrical tubular outer wall 242 into a hollow-cylindrical first compartment 258 and a cylindrical second compartment 259 which is coaxially surrounded by the first compartment 258. While the first compartment 258 forms the hollow-cylindrical main reservoir 251, the second compartment 259 forms the cylindrical vaporization zone 253. A first end cap 244 is attached to a first end of the reservoir body comprising the partition wall 241 and the tubular outer wall 242. The first end cap 244 sealingly closes the first compartment 258 at the first end of the reservoir body. At the opposite end, the reservoir body is closed by a second end cap 243 which comprises a recess similar to the bottom end cap 43 of the article 40 shown in FIG. 1. At a bottom portion, the vaporization cavity 253 is closed by a disc-shaped bushing 245. There, a capillary buffer reservoir 252 is formed between the inner surface of the second end cap 243 on the one side, and the end face of the cylindrical partition wall 241 and the disc-shaped bushing 245 on the other side. That is, the capillary buffer reservoir 252 basically is formed by a part of the recess-like fluid passage in the second end cap 243. The distance D between the inner surface of the bottom end cap 243 and the end face of the cylindrical partition wall 241 and the disc-shaped bushing 245 is chosen to be on the order of the effective capillary length, for example, in a range between 1 millimeter and 5 millimeter. Due to this, once filled with aerosol-forming liquid, the buffer reservoir 252 traps a certain amount of aerosol-forming liquid due to capillary action, even when the orientation of the article 240 is changed, for example, when the article 40 is turned form a substantially upright position as shown in FIG. 9 into an upside down position as shown in FIG. 10. Hence, the soaking section 275 of the liquid conduit 270 is always in contact with aerosol-forming liquid independent of the article position. The volume of the capillary buffer reservoir 252 is chosen such that the trappable amount of aerosol-forming liquid suffices at least for a few puffs.
[0154] In the present embodiment, the cylindrical partition wall 241 and the tubular outer wall 242 are separate parts which may be manufactured by extrusion. The first and the second end cap 243, 244 may be used to hold the partition wall 241 and the tubular outer wall 242 together.
[0155] For the purpose of the present description and of the appended claims, except where otherwise indicated, all numbers expressing amounts, quantities, percentages, and so forth, are to be understood as being modified in all instances by the term “about”. Also, all ranges include the maximum and minimum points disclosed and include any intermediate ranges therein, which may or may not be specifically enumerated herein. In this context, therefore, a number A is understood as A±5% of A. Within this context, a number A may be considered to include numerical values that are within general standard error for the measurement of the property that the number A modifies. The number A, in some instances as used in the appended claims, may deviate by the percentages enumerated above provided that the amount by which A deviates does not materially affect the basic and novel characteristic(s) of the claimed invention. Also, all ranges include the maximum and minimum points disclosed and include any intermediate ranges therein, which may or may not be specifically enumerated herein.
