Aerosol Generating System

Description

TECHNICAL FIELD

The present invention relates to an aerosol generating system comprising a case and a tobacco stick. More particularly, the present invention relates to such aerosol generating systems in the form of electronic cigarettes, e-cigarettes, vapor inhalators, vaping devices and related devices.

BACKGROUND

A conventional aerosol generating system 202 is shown in FIGS. 1 and 2.

The conventional aerosol generating system 202 includes a case 204 having an oven cavity 206. FIG. 1 is a cross-sectional view of the wall case 204. FIG. 2 is a detailed cross-sectional view of the oven cavity 206. As shown in FIG. 2, the oven cavity 206 includes a cylindrical wall 208, a bottom surface 210 and an opening portion 212.

The aerosol generating system 202 further includes a tobacco stick 214. The tobacco stick 214 includes a first end 216 facing the bottom surface 210 and a second end 218 longitudinally opposed to the first end 216.

With such an arrangement, an air flow path schematically depicted by the arrows 220 on FIG. 2 extends through the oven cavity 206 and the tobacco stick 214. As visible in FIG. 2, the air flow path 220 firstly extends through the opening portion 212, through a radial gap between the tobacco stick 214 and the cylindrical surface 208, through the first end 116 of the tobacco stick 214, through the tobacco particles contained in the tobacco stick 214 and through the second end 218 of the tobacco stick 214. The cylindrical surface 208 is able to heat the tobacco articles contained in the tobacco stick 214. By doing so, air flowing in the air flow path 220 flows through the heated tobacco particles, thus creating an aerosol which can be inhaled by the user.

However, with such an air flow path design, the oven cavity temperature drops at every puff because cold air flows against the cylindrical wall 208 before entering the tobacco stick 214. This cooling of the oven wall makes the vapor condense on the wall, leaving a deposit of dirtiness. This results in an inconvenience for the user, and even in getting the aerosol generating system so dirty that the user cannot even fit the tobacco stick in the oven cavity anymore.

WO 2022/049247 discloses an air flow passage including a frustoconical outer surface mounted in an oven cavity and which extends through an end of an aerosol generating article of a stick type. However, such an arrangement is not fully satisfactory because there is still a thermal connection between the cold air flow inside the case and the oven wall and because tobacco particles drop into the oven cavity. Also, such an arrangement is not compatible with an arrangement wherein the air flow is drawn from a location close to a second end of the tobacco stick.

There is therefore a need to facilitate maintenance of an aerosol generating system that would render the oven cavity cleaner and improve sensorial performance. It is thus an object of the present invention to provide such improved aerosol generating systems that can remedy the drawbacks of the conventional solutions.

SUMMARY

The mentioned drawbacks are remedied by the subject-matter of the independent claims. Further preferred embodiments of the present invention are defined in the dependent claims.

According to one embodiment of the present invention, there is provided an aerosol generating system comprising a case defining an oven cavity; the oven cavity having a bottom surface and an opening portion, a tobacco stick at least partially received in the oven cavity, the tobacco stick having a first end facing the bottom surface, and a first air flow path extending through the oven cavity and the tobacco stick, the first air flow path having an inlet fluidly connecting the first air flow path to an exterior of the oven cavity and an outlet fluidly connecting the first air flow path to an exterior of the tobacco stick, the inlet including a nozzle mounted on the bottom surface of the oven cavity and extending through the first end, the tobacco stick including an acetate tube adjacent to the first end, the acetate tube including an inner channel, the first air flow path extending through the inner channel.

By virtue of this embodiment, the cooling of the cylindrical surface of the oven cavity is avoided. The vapor thus no longer condenses on the cylindrical surface and the dirtiness evacuated with the vapor. Furthermore, this embodiment avoids tobacco particles to drop into the oven cavity due to the added acetate tube. This results in an improved maintenance of the aerosol generating system and in particular with the oven cavity cleaner being than in conventional solutions.

Preferably, the acetate tube includes a first frontal surface, a second frontal surface, a cylindrical surface extending between the first and second frontal surfaces, and an aperture extending between the cylindrical surface and the inner channel.

By virtue of such an aperture, part of the first air flow path may flow through the cylindrical surface of the acetate tube, which is not subject to dirtiness accumulation. Therefore, this improves the pressure drop consistency through the aerosol generating system and the experience of the user.

In another embodiment, the first frontal surface is proximal to the bottom surface and the second frontal surface is distal to the bottom surface, the inner channel including a blind bore extending from the first frontal surface.

Such an embodiment prevents even more tobacco articles from dropping into other parts of the aerosol generating system, and in particular into the nozzle. By doing so, pressure drop consistency through the aerosol generating system is even more improved.

Preferably, the nozzle includes a substantially frustoconical outer surface, a first axial portion extending through the bottom surface and a second axial portion extending through the first end in order to penetrate the tobacco stick, the first axial portion being proximate to a longer diameter end of the substantially frustoconical outer surface, and the second axial portion being proximate to a shorter diameter end of the substantially frustoconical outer surface.

Preferably, the substantially frustoconical outer surface includes a plurality of circumferential ribs.

Preferably, the substantially frustoconical outer surface includes an outer thread.

In another embodiment, the nozzle includes a cylindrical inner through-hole having a circular axial cross section.

Preferably, the cylindrical inner through-hole includes an inner thread.

Such designs of the nozzle allow it to best fit and seal into the tobacco stick to avoid unwanted secondary air flow while facilitating the tobacco stick insertion.

Preferably, the tobacco stick comprises a second end longitudinally opposed to the first end, and a thicker portion between the first end and the second end.

Such a thicker portion improves sealing of the radial gap between the tobacco stick and the cylindrical surface of the oven cavity in order to avoid unwanted secondary air flow from the opening portion despite the depression caused by puffing at the bottom of the oven cavity. A condensation of vapors on the cylindrical surface of the oven cavity is therefore even more avoided, so that dirtiness is evacuated even more effectively with the vapor.

Preferably, the tobacco stick fits slightly in the oven cavity.

Preferably, the thicker includes at least one layer of tipping paper.

With such an arrangement, the experience of the user is further enhanced by the use of tipping paper without involving a paper taste which is currently caused by the air to flow against the tipping paper in a conventional solution such as the one shown in FIGS. 1 and 2.

Preferably, the thickness of the layer of tipping paper is between 0.02 mm and 0.2 mm.

Preferably, the thicker portion includes 1 to 10 layers of tipping paper.

Such a design of the thicker portion allows the tobacco stick to fit slightly in the oven cavity.

Preferably, the inner channel includes a frustoconical recess having a smaller diameter end proximal to the bottom surface and a larger diameter end distal to the bottom surface.

It is also possible to foresee that the acetate tube includes an array of piercings extending towards a first frontal surface proximal to the bottom surface from a second frontal surface distal to the bottom surface.

Such designs of the inner channel make it possible to facilitate the distribution of air into the tobacco stick.

Preferably, the nozzle includes a sliding part.

By doing so, it is possible to provide a tobacco stick insertion sensor.

Preferably, the sliding part is ferromagnetic, and the sensor includes a hall effect sensor.

Such a design of the sliding part and the sensor allows providing a tobacco stick insertion sensor in a space-saving manner.

In another embodiment, the case includes an outer cavity, the oven cavity being located in the outer cavity so as to define a radial gap between the outer cavity and the oven cavity, and the aerosol generating system includes a thermal insulation layer arranged radially outside the oven cavity.

By doing so, it is possible to avoid even more effectively condensation of the vapor on the cylindrical surface of the oven cavity. Dirtiness may thus be further evacuated with the vapor.

One may also foresee a battery volume and/or an electronic unit, the case including a second air flow path extending continuously through the case, the second air flow path being in fluid communication with the inlet of the first air flow path, at least a portion of the second air flow path being proximate to the battery volume and/or the electronic unit.

By doing so, it is possible to use the air flow to cool down hotspots of the aerosol generating system, thus enhancing the user's experience.

Preferably, the aerosol generating system further includes a flavor reception space proximate to the bottom surface.

Such a flavor reception space makes it possible to add flavor to the input air in a particularly easy manner, only requiring the user to add drops of flavor or flavor tablets into the bottom of the oven cavity.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the present invention, which are presented for better understanding the inventive concepts and which are not to be seen as limiting the invention, will now be described with reference to the figures in which:

FIG. 1 is a cross-sectional view of a conventional aerosol generating system,

FIG. 2 is a detailed cross-sectional view of an oven cavity of the aerosol generating system of FIG. 1,

FIG. 3 is a detailed, cross-sectional view of an oven cavity of an aerosol generating system according to a first embodiment of the invention,

FIG. 4 is a detailed view, in perspective, of an acetate tube of a tobacco stick of the aerosol generating system of FIG. 3,

FIG. 5 is a perspective view of a nozzle of an aerosol generating system according to a second embodiment of the invention,

FIG. 6 is a perspective view of a nozzle of an aerosol generating system according to a third embodiment of the invention,

FIG. 7 is a perspective view of a nozzle of an aerosol generating system according to a fourth embodiment of the invention,

FIG. 8 is a cross-sectional view of an aerosol generating system according to a fifth embodiment of the invention,

FIG. 9 is a cross-sectional view of an aerosol generating system according to a sixth embodiment of the invention,

FIG. 10 is a detailed, cross-sectional view of an oven cavity of an aerosol generating system according to a seventh embodiment of the invention,

FIG. 11 is a detailed, cross-sectional view of an oven cavity of an aerosol generating system according to an eighth embodiment of the invention,

FIG. 12 is a detailed, cross-sectional view of an oven cavity of an aerosol generating system according to a ninth embodiment of the invention,

FIG. 13 is a perspective view of a nozzle of an aerosol generating system according to a tenth embodiment of the invention, and

FIG. 14 is a detailed, cross-sectional view of an oven cavity of an aerosol generating system according to an eleventh embodiment of the invention.

DETAILED DESCRIPTION

Embodiments of the present invention will now be described with reference to the following figures. The same or sequentially similar numbers are used throughout the figures to reference like features and components.

Referring now to FIG. 3, an aerosol generating system 2 includes a case 4 defining an oven cavity 6. In the depicted embodiment, the oven cavity 6 forms a cylinder of revolution. In the present description, the words “axial” and “radial” and their derivates will be understood as referring to a circular axial cross-section of the oven cavity 6. The oven cavity 6 includes a cylindrical surface 8, a bottom surface 10 and an opening portion 12.

The case 4 further includes an outer cavity 14 having a cylindrical shape and an axial cross-section larger than an axial cross-sectional of the oven cavity 6. The oven cavity 6 is located inside the outer cavity 14. By such an arrangement, a radial gap 16 is defined between the outer cavity 14 and the oven cavity 6.

Radially outside the oven cavity 6, a thermal insulation layer 18 is provided in order to provide a thermal insulation between the oven cavity 6 and the radial gap 16.

The aerosol generating system 2 further includes a tobacco stick 20. The tobacco stick 20 is partially received in the oven cavity 6. The tobacco stick 20 includes, in this order, a first end 22, an acetate tube 24, a main body 26 and a second end 28. The first end 22 faces the bottom surface 10 of the oven cavity 6. The second end 28 is longitudinally opposed to the first end 22. The second end 28 is further away from the bottom surface 10 than the opening portion 12. In other words, the opening portion 12 is located between the ends 22 and 28. The acetate tube 24 and the main body 26 may be wrapped in a layer of tipping paper 29 (visible in FIG. 4).

The tobacco stick 20 includes a thicker portion 30 provided between the first end 22 and the second end 28. In the depicted embodiment, the thicker portion 30 is adjacent to the second end 28 and long enough to extend further away from the second end 28 than the opening portion 12. In this way, despite the depression caused by the puffing at the bottom of the oven cavity 6, a secondary unwanted air flow between the tobacco stick 20 and the cylindrical surface 8 is avoided.

In the depicted embodiment, the thicker portion 30 is a layer of tipping paper. The thickness of the layer of tipping paper 30 is between 0.02 mm and 0.2 mm. As an alternative, the thicker portion may include at least two layers of tipping paper, and preferably between 1 and 10 layers of tipping paper 30.

Referring now to FIG. 4, the acetate tube 24 includes an inner channel 32, a cylindrical surface 34 extending between a first frontal surface 36 and a second frontal surface 38. The first frontal surface 36 faces the bottom surface 10 of the oven cavity 6. The second frontal surface 38 is adjacent to the main body 26 and therefore is further away from the bottom surface 10 than the first frontal surface 36.

In the first embodiment, the inner channel 32 extends between the first frontal surface 36 and the second frontal surface 38.

The acetate tube 24 further includes at least one aperture 40 extending between the cylindrical surface 34 and the inner channel 32.

The aerosol generating system 2 further includes a nozzle 41 mounted on the bottom surface 10 of the oven cavity 6. More specifically, the nozzle 41 extends through the bottom surface 10, the thermal insulation layer 18 and the first end 22 of the tobacco stick 20. In the present embodiment, as visible in FIG. 3, the nozzle 41 extends in the inner channel 32.

By virtue of this arrangement, the aerosol generating system 2 defines an upstream air flow path 42 and a downstream air flow path 44.

The upstream air flow path 42 extends through the case 4 upstream of the oven cavity 6. The upstream air flow path 42 includes an air inlet 46 formed by an opening portion of the outer cavity 14, and an air outlet 48 formed by the nozzle 41. Thus, following a puff by the user on the tobacco stick 20, air flowing in the upstream air flow path 42 passes through the opening portion of the outer cavity 14, in the radial gap 16 extending between the cylindrical surface of the outer cavity 14 and the thermal insulation layer 18 and reaches the nozzle 41.

The downstream air flow path 44 extends through the oven cavity 6 and the tobacco stick 20. The downstream air flow path 44 includes an inlet 50 corresponding to the nozzle 41 and an outlet 52 corresponding to the second end 28 of the tobacco stick 20. The inlet 50 thus fluidly connects the downstream air flow path 44 to the upstream air flow path 42 which is located outside the oven cavity 6. The outlet 52 fluidly connects the downstream air flow path 44 to an exterior of the tobacco stick 20. Thus, following a puff by the user on the tobacco stick 20, air flowing in the downstream air flow path 44 firstly flows through the nozzle 41, then through the inner channel 32 of the acetate tube 24, optionally through the aperture 40, and then through the heated tobacco particles of the main body 26 of the tobacco stick 20. Eventually, air flowing in the downstream air flow path 44 flows through the outlet 52 formed by the second end 28 in order to be inhaled by the user.

Referring now to FIG. 5, it is depicted a nozzle 54 according to a second embodiment of the invention. The nozzle 54 may be used in an aerosol generating system such as the aerosol generating system 2 of the first embodiment of the invention.

As well as the nozzle 41, the nozzle 54 is mounted on the bottom surface 10 of the oven cavity 6 and extends through the first end 22 of the tobacco stick 20. More specifically, as well as the nozzle 41, the nozzle 54 implements a fluid communication between the inner space of the outer cavity 14 and the inner channel 32 of the acetate tube 24 of the tobacco stick 20.

The nozzle 54 includes an outer surface 56 being substantially frustoconical. The outer surface 56 includes a longer diameter end 58 and a smaller diameter end 60. The nozzle 54 includes a first axial portion 62 adjacent to the longer diameter end 58, a second axial portion 64 adjacent to the smaller diameter end 60 and a third axial portion 66 located between the axial portions 62 and 64.

The first axial portion 62 extends through the bottom surface 10 of the oven cavity 6. In other words, the longer diameter end 58 is adjacent to an outer surface of the thermal insulation layer 18. The limit between the first axial portion 62 and the third axial portion 66 is adjacent to the bottom surface 10. The second axial portion 64 extends through the first end in order to penetrate the tobacco stick 20. In other words, the smaller diameter end 60 is inserted in the tobacco stick 20. More specifically, the smaller diameter end 60 is received inside the inner channel 32 of the acetate tube 24. The limit between the second axial portion 64 and the third axial portion 66 is adjacent to the first end 22 of the tobacco stick 20.

The nozzle 54 includes a plurality of, e.g. three circumferential ribs 68. The circumferential ribs 68 allow the nozzle 54 to best fit and seal into the tobacco stick 20 to avoid unwanted secondary air flow by facilitating the insertion of the tobacco stick 20.

The nozzle 54 includes an inner through-hole 70 forming the inlet 15. The inner through-hole 70 forms a cylinder of revolution around the same axis of revolution as the frustoconical outer surface 56. In other words, the inner through-hole 70 has a circular axial cross-section around the same axis as the circular axial cross-section of the outer surface 56.

The inner through-hole 70 includes an inner thread 72 able to cooperate with an outer thread provided integrally with the bottom surface 10. Alternatively, or in addition, an internal thread is provided integrally to the tobacco stick 20.

Referring now to FIG. 6, a nozzle 74 according to a third embodiment of the invention is depicted. The nozzle 74 may be used in an aerosol generating system such as the aerosol generating system 2 of the first embodiment of the invention.

In particular, as well as the nozzle 54, the nozzle 74 includes a substantially frustoconical outer surface 56, a longer diameter end 58, a shorter diameter end 60, a first axial portion 62 extending through the bottom surface 10, a second axial portion 64 extending through the first end 22 in order to penetrate the tobacco stick 20, a third axial portion 66 and a cylindrical inner through-hole 70.

The nozzle 74 mainly differs from the nozzle 54 in that it includes ribs 76 having an extending direction forming a variable angle with respect to the circumferential direction of the outer surface 56. Also, the nozzle 74 does not include an inner thread on an inner surface of the through-hole 70.

Referring now to FIG. 7, a nozzle 78 according to a fourth embodiment of the invention is depicted. The nozzle 78 may be used in an aerosol generating system such as the aerosol generating system 2 of the first embodiment.

As well as the nozzles 54 and 74, the nozzle 78 includes a substantially frustoconical outer surface 56, a longer diameter end 58, a shorter diameter end 60, a first axial portion 62 extending through the bottom surface 10, a second axial portion 64 extending through the first end 22 in order to penetrate the tobacco stick 20 and a third axial portion 66. As well as the nozzles 54 and 74, the nozzle 78 further includes an inner through-hole 70, optionally provided with an inner thread 72.

As visible in FIG. 7, the nozzle 78 includes an outer thread 80 provided on the wall length of the outer surface 56.

Referring now to FIG. 8, an aerosol generating system 81 according to the fifth embodiment of the invention is depicted.

The aerosol generating system 81 includes an electronic unit 82 and a battery volume 83 provided inside the case 4. More specifically, the electronic unit 82 is provided below the oven cavity 6, and the battery volume 83 is provided on a side opposed to a side containing the oven cavity 6.

In the fifth embodiment, the upstream air flow path 42 and the downstream air flow path 44 are shown by a line 84. As visible in FIG. 8, the upstream air flow path 42 extends continuously through the case 4 between the air inlet 46 provided on a side surface of the case 44 and the nozzle 41. Also, the upstream air flow path 42 includes a portion 85 proximate to the electronic unit 82.

By virtue of this arrangement, it is possible to use the air inlet in order to cool down a hotspot of the aerosol generating system 81 such as the electronic unit 82.

Referring now to FIG. 9, an aerosol generating system 86 according to a sixth embodiment of the invention is depicted.

As well as the aerosol generating system 81, the aerosol generating system 86 includes an electronic unit 82 and a battery volume 83. The aerosol generating system 86 mainly differs from the aerosol generating system 81 in that the air inlet 46 is provided on a bottom surface of the case 4. As a result, the upstream air flow path 42 includes a portion 87 proximate to the battery volume 83, in addition to the portion 85 proximate to the electronic unit 82.

Therefore, a further hotspot of the aerosol generating system 86 may be cooled down by the air inlet.

Referring now to FIG. 10, an aerosol generating system 88 according to a seventh embodiment of the invention is depicted.

The aerosol generating system 88 mainly differs from the aerosol generating system 2 in that an inner space of the outer cavity 14, located below the bottom surface 10, includes a flavor reception space 89. The user may add flavor drops or flavor tablets into the flavor reception space 89 in order to add a flavor to the aerosol generated and generate a further enhanced user experience.

Referring now to FIG. 11, an aerosol generating system 90 according to an eighth embodiment is depicted.

The aerosol generating system 90 mainly differs from the aerosol generating system 2 in that the inner channel 32 of the acetate tube 24 includes a frustoconical recess 91. The frustoconical recess 91 includes a smaller diameter end 92 and a larger diameter end 93. The smaller diameter end 92 is closer to the bottom surface 10 than the larger diameter end 93. The nozzle 41 is inserted through the smaller diameter end 92.

Referring now to FIG. 12, an aerosol generating system 94 according to a ninth embodiment of the invention is depicted.

The aerosol generating system 94 differs from the aerosol generating system 2 in that the inner channel is formed by an array of piercings 95. Furthermore, the aerosol generating system 94 includes a plurality of nozzles 41, e.g. one nozzle 41 per piercing 95. In the depicted embodiment, the piercings 95 extend from the second frontal surface 38 towards the first frontal surface 36. At approximately half the length of the acetate tube 24, the piercings 95 communicate with the inner channel 32.

Referring now to FIG. 13, a nozzle 96 according to a tenth embodiment is depicted. The nozzle 96 may be used in any one of the aerosol generating systems 2, 81, 86, 88, 90 and 94.

As visible in FIG. 13, the nozzle 96 is similar to the nozzle 74 of the third embodiment and includes, in particular, ribs 76 having an extending direction forming a variable angle with respect to the circumferential direction of the outer surface 56. However, a shape of the outer surface 56 and of the inner through-hole 70 may be modified, for example in order to be replaced with features of the nozzles 54 and 78.

The nozzle 96 includes a sliding part 97 inserted into the through-hole 70. The sliding part 97 is able to move, inside the trough-hole 70, along an axial direction of the nozzle 96. In the depicted example, the sliding part 97 is a spherical ball having a diameter slightly lower than a diameter of the axial cross-section of the through-hole 70.

The nozzle 96 further includes a helical spring 98. The helical spring 98 includes a lower end 99 attached to the nozzle 96 and an upper end 100 attached to the sliding part 97. The helical spring 98 is configured to work in compression, that is, to work by pushing the sliding part 97 in a direction extending from the lower, longer diameter end 58 towards the upper, shorter diameter end 60. By virtue of this arrangement, when the tobacco stick 20 is inserted in the oven cavity 6, and when the nozzle 96 is properly inserted into the acetate tube 24, the sliding part 97 is pushed towards the lower end 99 and the helical spring 98 is compressed. When the tobacco stick 20 is removed, the sliding part 97 is no longer pushed by the tobacco stick 20 and reverts to its rest position, adjacent to the shorter diameter end 60 and further away from the lower end 99 than when it is pushed by the tobacco stick 20.

The nozzle 96 further includes a sensor 101. The sensor 101 is able to detect the position of the sliding part with respect to the nozzle 96. More specifically, the sensor 101 is able to detect if the sliding part 97 is adjacent to the shorter diameter end 60, as depicted in FIG. 13, or if it is at a compressed position of the helical spring 98, which is close to the lower end 99 of the helical spring 98.

In the present embodiment, the sliding part 97 is made of a ferromagnetic material and the sensor 101 is a hall effect sensor.

Referring now to FIG. 14, an aerosol generating system 102 according to an eleventh embodiment of the invention is directed.

The aerosol generating system 102 differs from the aerosol generating system 2 in that the inner channel 32 includes a non-through-hole 104 extending from the first frontal surface 36 of the acetate tube 24 towards the second frontal surface 38. The non-through-hole 104 communicates fluidly with the aperture 40 of the acetate tube 24.

Hence, the aerosol generating system 102 mainly differs from the aerosol generating system 2 in that the hole forming the inner channel 32 does not extend on the wall length of the acetate tube 24 between the frontal surfaces 36 and 38. Such an arrangement allows further reducing tobacco particles dropping into the nozzle, thus improving the pressure drop consistency through the aerosol generating system 102.

Although all detailed embodiments have been described, these only serve to provide a better understanding of the invention defined by the independent claims and are not to be seen as limiting.