Gas-burning aerosol-generating device with catalyst

Abstract

An aerosol-generating device (1) comprises a receiving body (2) having a longitudinal axis and configured to receive an aerosol-generating article (100) and having a closed end (2a) and an open end (2b), opposed to the closed end (2a) configured to insert the aerosol-generating article (100); a gas-burning heating element (3) to heat the receiving body (2); wherein the gas-burning heating element (3) comprises a heating chamber (4) housing the receiving body (2) and a catalyst member (5) connected to the receiving body (2); wherein the receiving body (2) presents a heat transfer member to transfer heat from the catalyst member (5) to a central portion (2c) of the receiving body (2).

Description

[0001] Gas-burning aerosol -generating device with catalyst

[0002] Technical field

[0003] The present invention relates to an aerosol-generating device. In particular, the present invention relates to a gas-burning aerosol-generating device comprising a catalyst.

[0004] Specifically, the present invention relates to heat-not-burn (HNB) devices.

[0005] Background

[0006] Aerosol-generating devices, also known as heat-not-burn (HNB) devices, are commonly used to heat heated tobacco sticks (HTS) products which are widely used in the market and offer reduced risk compared to combustible products.

[0007] The known aerosol-generating devices heat a portion of tobacco to create an aerosol that is inhaled by the user. In this regard, they are equipped with a heater to heat the tobacco, thereby generating the aerosol.

[0008] The heater can be electric. However, gas-burning heaters are also known. Specifically, they use butane, propane or a mixture of both reacting with oxygen over a catalyst to produce heat, warming a tobacco portion and generating inhalable vapour.

[0009] Gas-burning heaters generally provide large amounts of thermal energy, but the aerosol generation can be quite ineffective.

[0010] This is due to the vapor inhalation airflow which only passes over the top of the tobacco portion and not through the entire portion. Additionally, the heat from the gas-burning heater is mainly focused on an end of the tobacco potion which is distal with respect to a filter portion. In other words, the heat is mainly concentrated upstream with respect to the aerosol flow.

[0011] That means that the aerosol is generated in a relatively hot part of the tobacco and then flows downstream through a relatively colder part of the tobacco portion where it condenses due to the lower temperature, reducing the total aerosol volume.

[0012] Summary of the Invention

[0013] In view of the above, it is an object of the present invention to provide an aerosol-generating device configured to increase the amount of aerosol generated and delivered to the user, improving the sensory experience.

[0014] This is achieved by means of the article in accordance with claim 1.

[0015] According to the invention, an aerosol-generating device comprises a receiving body having a longitudinal axis and being configured to receive an aerosol-generating article and having a closed end and an open end, opposed to the closed end configured to insert the aerosol-generating article; a gasburning heating element to heat the receiving body; wherein the gas-burning heating element comprises a heating chamber housing the receiving body and a catalyst member connected to the receiving body; the receiving body presents a heat transfer member to transfer heat from the catalyst member to a central portion of the receiving body.

[0016] Due to this configuration, the heat generated by the gasburning heating element is distributed more uniformly along the receiving body. More in detail, the central portion is more heated and, consequently, when the aerosol-generating article comprising an aerosol-generating portion is inserted into the receiving body, the aerosol-generating portion is arranged at the central portion of the receiving body and it is heated more intensely and more uniformly.

[0017] This allows the aerosol formed in the aerosol-generating portion flowing downstream not to pass through colder regions, thereby avoiding condensation of the aerosol.

[0018] The amount of aerosol generated and delivered to the user is therefore increased, improving the sensory experience.

[0019] According to a preferred aspect of the invention, the catalyst member may be arranged in proximity of the closed end of the receiving body.

[0020] This can simplify the manufacturing of the aerosol-generating device as the catalyst member can be arranged in an easy position and can be realized in a simple shape.

[0021] According to a preferred aspect of the invention, the heat transfer member may comprise a groove located on an external surface of a lateral wall of the receiving body extending from the closed end to the central portion of the receiving body; preferably the groove being helical.

[0022] This feature allows the creation of a convective motion of heat generated at the catalyst element that moves from the catalyst element along the receiving body towards its central portion to distribute the heat uniformly along the lateral surface of the body itself.

[0023] Advantageously, the helical shape of the groove allows the heat to uniformly wrap the entire lateral surface, improving the uniformity of the heat. According to a preferred embodiment, the receiving body may have a thickness decreasing from the closed end to the open end.

[0024] Due to this feature, the heat flux through the receiving body is constant along the full longitudinal axis thereof. Indeed, when the burning gas flows from the closed end to the open end, the temperature of the gas decreases from the closed end to the open end. As the thickness of the receiving body decreases accordingly, the heat flux reaching the aerosolgenerating portion can be kept constant, avoiding cooler portions that would determine an undesired condensation of the aerosol.

[0025] According to a preferred embodiment, the receiving body may have an external truncated cone shape along the longitudinal axis thereof.

[0026] The shape of the receiving body allows to transfer heat more efficiently towards the central portion, while keeping the aerosol-generating article in a stable position in the receiving body.

[0027] According to a preferred embodiment, the receiving body may have a circular cross section with respect to the longitudinal axis; the diameter of the circular cross section at the closed end may be greater than the diameter of the circular cross section at the central portion.

[0028] Due to this feature, when the aerosol-generating article is inserted into the receiving body and its aerosol generating portion is arranged at the central portion, the aerosol generating portion of the aerosol-generating article can be heated more intensely.

[0029] Indeed, as the central portion has a smaller diameter, the density of the heat transferred by means of the heat transfer member is greater. Additionally, the distance between the receiving body and the aerosol-generating article at the central portion is minimal and the aerosol-generating portion can be more efficiently heated.

[0030] According to a preferred embodiment, the receiving body may comprise an end portion at the open end having a constant diameter.

[0031] This end portion is helpful to maintain the aerosol-generating article in the correct position when it is inserted in the receiving body.

[0032] According to a preferred embodiment, the heating chamber may have a truncated cone shape along a longitudinal axis thereof.

[0033] The shape of the heating chamber may contribute to direct the flow of the burning gas toward the receiving body to promote heat exchange therebetween.

[0034] According to a preferred embodiment, the heating chamber may present at least an inlet for the entrance of at least the gas or a mixture of the gas and air and an outlet for the exit of exhausted gas; the inlet may be located at the closed end of the receiving body and the outlet is located at one end of the heating chamber opposite the inlet along the longitudinal direction.

[0035] The configuration of the inlet and the outlet allows a flow of the burning gas from the closed end of the receiving body to the open end of the receiving body. In other words, the burning gas flows towards the central portion of the receiving body having the minor diameter and helps transfer the heat to the central portion.

[0036] According to a preferred embodiment, the inlet may be coaxial to the longitudinal axis of the receiving body. The axial symmetry of the inlet with respect to the receiving body allows a flow of gas or a mixture of gas and air that develops uniformly around the receiving body, ensuring uniform heating of the same.

[0037] According to a preferred embodiment, the catalyst member may be arranged inside the heating chamber.

[0038] This allows the combustion reaction to take place inside the combustion chamber close to the receiving body to increase the heating efficiency of the latter.

[0039] According to a preferred embodiment, the catalyst member may be coaxial to the longitudinal axis of the receiving body.

[0040] This configuration allows the combustion reaction to take place symmetrically with reference to the receiving body. Consequently, the heat generated by the exothermic reaction can reach the receiving body more uniformly. Additionally, this can increase the efficiency of transferring heat to the central portion via the heat transfer member.

[0041] According to a preferred embodiment, the catalyst member may be in contact with the closed end of the receiving body.

[0042] Due to this feature, the heat generated by the exothermic reaction can be directly transferred on the receiving body and from the closed end thereof to the central portion via the heat transfer member in a quick and efficient way.

[0043] Additionally, the contact area between the catalyst member and the closed end of the receiving body is the most effective area for the burning reaction to take place. It also ensures the maximum path length for the reaction to take place to improve the efficiency of the device. According to a preferred embodiment, the catalyst member may be in contact with a bottom wall of the heating chamber.

[0044] This configuration allows a more stable mechanical coupling of the catalyst member between the heating chamber and the receiving body.

[0045] According to a preferred embodiment, the catalyst member may be made with one of vanadium phosphorus oxide (VPO), VOx / MgO-γAl2O3, Ni-Mo / Al2O3, palladium (Pd), platinum (Pt), or a combination thereof.

[0046] The mentioned chemical compounds used as the catalyst member allow to obtain an efficient catalytic reaction which makes the combustion reaction quicker generating a greater amount of heat.

[0047] According to a preferred embodiment, the aerosol-generating article may comprise at least a filter portion and an aerosolgenerating portion connected to the filter portion and having a first end proximal to the filter portion and a second end distal from the filter portion; in use, when the aerosolgenerating article is received in the receiving body, the first end may be configured to be located at the central portion of the receiving body.

[0048] Due to this configuration, the heat generated by the gasburning heating element can be directed more efficiently to the first end of the aerosol-generating portion. As the first end of the aerosol-generating portion is arranged at the downstream side of the aerosol-generating portion, when the aerosol generated at the upstream side thereof flows downstream, it passes through a region of the portion having a higher temperature. Therefore, the aerosol does not condense.

[0049] The amount of aerosol generated and delivered to the user is therefore increased, improving the sensory experience. Brief Description of the Drawings

[0050] Hereinafter, the invention will be further described with reference to a preferred embodiment thereof, in which

[0051] Fig. 1 shows a schematic view of an aerosol-generating device according to an embodiment of the present invention;

[0052] Fig. 2 shows a schematic view of a detail of the aerosolgenerating device of Fig. 1;

[0053] Fig. 3 shows a schematic view of a first example of an aerosolgenerating device not forming part of the invention;

[0054] Fig. 4 shows a schematic view of a variation of the example of Fig. 3;

[0055] Fig. 5 shows a schematic view of a second example of an aerosolgenerating device not forming part of the invention.

[0056] Detailed Description of Preferred Embodiments

[0057] With reference to Figs. 1 and 2, an aerosol-generating device according to the invention is represented with the numeral 1.

[0058] The aerosol-generating device 1 can be used with an aerosolgenerating article 100 which can be inserted in the aerosolgenerating device 1 to generate an aerosol.

[0059] The aerosol-generating article 100 comprises at least a filter portion 101 and an aerosol-generating portion 102 connected to the filter portion 101. The aerosol-generating portion 102 is connected to the filter portion 101 by means of a tipping paper (not shown) covering both the aerosol-generating portion 102 and the filter portion 101. The filter portion 101 is arranged downstream of the aerosolgenerating portion 102 and extends along the longitudinal direction.

[0060] The term "downstream" refers to the flow of air passing through the aerosol-generating article 100 during use, and in particular during a puff by the user.

[0061] The aerosol-generating portion 102 presents a first end 102a proximal to the filter portion 101 and a second end 102b distal from the filter portion 101.

[0062] The aerosol-generating portion 102 may comprise a plantfilling material comprising tobacco material, botanicals, or a combination of both. When comprising tobacco material, the latter may comprise lamina and / or stems. It may also alternatively or in combination comprise reconstituted tobacco sheet materials formed of dry tobacco leaves in particulate form so as to have a mean particle size of 20 pm or more but not more than 200 pm, which are then homogenized into a sheet-processed material. The aerosol-generating portion 102 content is typically between about 200 mg and 800 mg, preferably between 250 mg and 350 mg for a 20 mm length and 22 mm circumference.

[0063] Various kinds of tobacco leaves can be used for making a tobacco containing aerosol generating substrate to achieve the desired taste.

[0064] Alternatively, the aerosol-generating portion 102 may comprise a non-plant-filling material. For example, the non-plantfilling material may comprise cellulose comprising flavourings.

[0065] The filter portion 101 may be made of cellulose acetate.

[0066] A cooling section 103 can be arranged between the filter portion 101 and the second end 102b of the aerosol-generating portion 102. The cooling section 103 may comprise a tubular element, for example made of acetate and connected to the filter portion 101, and / or a paper tube, for example connected to the aerosol-generating portion 102.

[0067] A front plug 104 can be connected to the aerosol-generating portion 102 at the second end 102b thereof. For example, the front plug 104 may be made of acetate.

[0068] The aerosol-generating device 1 comprises a receiving body 2 configured to receive and house the aerosol-generating article 100.

[0069] The receiving body 2 has a longitudinal shape along a longitudinal axis.

[0070] Preferably, the receiving body 2 may be configured to receive and house the aerosol-generating article 100 having a cylindrical shape. More preferably, the receiving body 2 may be configured to receive and house the aerosol-generating article 100 having the aerosol-generating portion 102 cylindrical -shaped.

[0071] Preferably, the receiving body 2 has a circular cross-section to the longitudinal axis. In other words, the receiving body 2 has an annular cross-section to the longitudinal axis with constant radius.

[0072] The receiving body 2 presents a closed end 2a, and an open end 2b opposed to the closed end 2a. In use, the aerosol-generating article 100 can be inserted in the receiving body 2 through the open end 2a.

[0073] Preferably, the receiving body 2 may have a thickness decreasing from the closed end 2a to the open end 2b. Consequently, the heat flux through the receiving body 2 may be maintained substantially constant along a longitudinal direction.

[0074] Alternatively, the receiving body 2 may be configured such that the heat flux increases towards the central portion 2c of the receiving body 2. For example, this might be achieved by an appropriate thickness profile along the longitudinal direction.

[0075] Consequently, the aerosol-generating portion 102 of the aerosol-generating article 100 can be heated more at the first end 102a.

[0076] The receiving body 2 may have an external truncated cone shape along the longitudinal axis thereof. In detail, the receiving body 2 may comprise at least a portion having a truncated cone shape along the longitudinal axis of the receiving body 2.

[0077] Internally, the receiving body 2 may present a cylindricalshaped receiving space for receiving and housing the aerosolgenerating article 100.

[0078] In use, when the aerosol-generating article 100 is inserted into the receiving body 2, the aerosol-generating portion 102 is arranged inside the truncated cone shaped portion of the receiving body 2.

[0079] The receiving body 2 may comprise a lateral wall 2L and a bottom wall 2M connected to the lateral wall 2L and defining the closed end 2a. The lateral wall 2L may have constant thickness.

[0080] In use, when the aerosol-generating article 100 is inserted in the receiving body 2, the distance of a lateral surface of the aerosol-generating article 100 from the lateral wall 2L of the receiving body 2 at the first end 102a of the aerosol- generating article 100 is less than the distance of the lateral surface of the aerosol-generating article 100 from the lateral wall 2L of the receiving body 2 at the second end 102b of the aerosol-generating article 100.

[0081] This may contribute to heat more uniformly the aerosol-generating portion 102 at the first end 102a thereof rather than at the second end 102b to avoid cooler portions thereof.

[0082] A portion of the receiving body 2 having the minimum diameter of the circular cross section is defined as a central portion 2c of the receiving body 2.

[0083] It should be noted that the diameter may be measured with reference to an internal face of the lateral wall 2L.

[0084] However, as the thickness of the lateral wall 2L is constant, the same reasoning can be made also considering the diameter measured with reference to an external face of the lateral wall 2L.

[0085] In use, when the aerosol-generating article 100 is introduced in the receiving body 2, the aerosol-generating portion 102 may be arranged at least at the minimum diameter portion.

[0086] Additionally, the diameter of the circular cross section at the closed end 2a is greater than the diameter of the circular cross section at central portion 2c.

[0087] In use, when the aerosol-generating article 100 is introduced in the receiving body 2, the first end 102a of the aerosolgenerating portion 102 may be arranged at the minimum diameter portion of the receiving body 2. Further, the second end 102b of the aerosol-generating portion 102 may be arranged in the vicinity of, or at, the maximum diameter portion of the receiving body 2. Preferably, the receiving body 2 may further comprise an end portion 2d. The open end 2b of the receiving portion is arranged at the end portion 2d.

[0088] Preferably, the end portion 2d may have a constant diameter. Preferably, the constant diameter may be equal to the minimum diameter of the circular cross of the central portion 2c.

[0089] Preferably, the constant diameter may be equal to the diameter of the aerosol-generating article 100 to be introduced in the receiving body 2.

[0090] The receiving body may be made of metal. For example, the receiving body may be made of stainless steel or aluminium.

[0091] The aerosol-generating device 1 according to the invention further comprises a gas-burning heating element 3 to heat the receiving body 2 and, consequently, the aerosol-generating portion 102 of the aerosol-generating article 100.

[0092] In detail, the gas-burning heating element 3 comprises a heating chamber 4 which houses the receiving body 2 and a catalyst member 5 which is connected to the receiving body 2.

[0093] In this regard, the heating chamber 4 may further comprise at least a lateral wall 4a and a bottom wall 4b connected to each other to define a space in which the receiving body 2 is housed.

[0094] Therefore, the heating chamber 4 may be defined as the portion of the space between the lateral wall 4a and a bottom wall 4b and the receiving body 2.

[0095] The heating chamber 4 may present at least an inlet 6 for the entrance of at least the gas or a mixture of gas and air. According to the embodiment disclosed in Fig. 1, the inlet 6 of the heating chamber 4 introduces a mixture of gas and air.

[0096] In this regard, the aerosol-generating device 1 may comprise a tank 9 for the containment of gas, for example butane gas, and a gas duct 10. The tank 9 may comprise a fill nozzle 16 to fill the tank 9 with gas.

[0097] Additionally, the aerosol-generating device 1 may comprise an air duct 11 for the introduction of air. Both the gas duct 10 and the air duct 11 join to a carburettor 12.

[0098] The carburettor 12 may be configured to mix the gas coming from the tank 9 through the gas duct 10 with the air coming from the outside through the air duct to create the mixture.

[0099] A mixture duct 13 extends from the carburettor 12 to the inlet 6 of the heating chamber 4 to deliver the mixture thereto.

[0100] A valve (not illustrated) may be provided to regulate the opening and closing of the gas flow. The valve may be arranged for example along the gas duct 10.

[0101] Additionally, an ignition member (not shown) may be provided to initiate the combustion reaction. For example, the ignition member may comprise a piezoelectric element arranged downstream the carburettor 12, for example along the mixture duct 13 or inside the heating chamber 4.

[0102] An ignition switch 14 may be provided to activate the ignition member and / or the valve.

[0103] According to the embodiment shown, the inlet 6 may be located at the closed end 2a of the receiving body 2. More in detail, the inlet 6 may be located at the bottom wall 4b of the heating chamber 4. Specifically, the inlet 6 may be coaxial to the longitudinal axis of the receiving body 2.

[0104] Further, the heating chamber 4 may present at least an outlet 7 for the exit of exhausted gas.

[0105] Preferably, the outlet 7 is arranged at one end of the heating chamber 4 opposite the inlet 6 along the longitudinal direction.

[0106] According to the embodiment shown in the figures, the outlet 7 is arranged at the central portion 2c of the receiving body 2 and / or at the end portion 2d.

[0107] An exhausted gas duct 15 may extend from the outlet 7 to the outside to evacuate the exhausted gas coming from the combustion reaction.

[0108] According to the embodiment shown in the figures, the heating chamber 4 may have a truncated cone shape along a longitudinal axis thereof. Preferably, the heating chamber 4 may have a circular cross section with respect to the longitudinal axis.

[0109] Specifically, the lateral wall 4a of the heating chamber 4 may slope such that the diameter of the circular cross section at the inlet 6 is greater than the diameter of the circular cross section at the outlet 7.

[0110] This might allow the burning gas flow to be forced against the receiving body 2 to promote a heat exchange therebetween.

[0111] Preferably, the catalyst member 5 may be arranged inside the heating chamber 4. More in detail, the catalyst member 5 may be arranged in proximity of the closed end 2a of the receiving body 2. In accordance with the embodiment shown in the figures, the catalyst member 5 may be coaxial to the longitudinal axis of the receiving body 2.

[0112] Preferably, the catalyst member 5 may be in contact with the closed end 2a of the receiving body 2.

[0113] Preferably, the catalyst member 5 may face the inlet 7.

[0114] Preferably, the catalyst member 5 may be in contact with the bottom wall 4b of the heating chamber 4.

[0115] The catalyst member 5 may be disc shaped. Additionally, the catalyst member 5 may be a sponge-like body.

[0116] For example, the catalyst member 5 may be made with one of vanadium phosphorus oxide (VPO), VOx / MgO-γAl2O3, Ni-Mo / Al2O3, palladium (Pd), platinum (Pt), or a combination thereof.

[0117] According to the invention, the receiving body 2 presents a heat transfer member to transfer heat from the catalyst member 5 to the central portion 2c of the receiving body 2.

[0118] Specifically, the heat transfer member may comprise a groove 8 located on an external surface of the lateral wall 2L of the receiving body 2 (see fig. 2 ). Preferably, the groove 8 may extend from the closed end 2a to the central portion 2c of the receiving body 2. Preferably, the groove 8 may be helical shaped.

[0119] Therefore, the heat generated by the combustion reaction at the catalyst member 5 can be transferred to the central portion.

[0120] In use, when the aerosol-generating article 100 is inserted in the receiving body 2, the first end 102a proximal to the filter portion 102 is arranged approximately at the central portion 2c of the receiving body 2.

[0121] In this way, the aerosol-generating portion 102 is heated more uniformly and more intensely in the downstream part thereof, avoiding colder portions which would cause a partial condensation of the aerosol generated in the upstream part of the aerosol-generating portion 102.

[0122] The aerosol-generating device 1 may comprise a casing 17 in which the aforementioned elements are contained.

[0123] Additionally, an insulator 18 may be provided in the casing 17 to thermally isolate the casing 17.

[0124] The following is a description of further examples of aerosolgenerating devices (see Figs. 3 to 5).

[0125] The aerosol-generating devices according to the examples are configured to be used with the aerosol-generating article 100 above described.

[0126] An aerosol-generating device 1' according to the examples comprises a receiving body 2' configured to receive and house the aerosol-generating article 100.

[0127] The receiving body 2' has a longitudinal shape along a longitudinal axis. Preferably, the receiving body 2' has a circular cross-section to the longitudinal axis.

[0128] The receiving body 2' presents a closed end 2a' and an open end 2b', opposed to the closed end 2a'. In use, the aerosolgenerating article 100 can be inserted in the receiving body 2' through the open end 2a'. The receiving body 2' may comprise a lateral wall 2L' and a bottom wall 2M' connected to the lateral wall 2L' and defining the closed end 2a'.

[0129] Preferably, the receiving body 2' may be cylindrical-shaped.

[0130] The aerosol-generating device 1' according to the examples further comprises a gas-burning heating element 3' to heat the receiving body 2' and, consequently, the aerosol-generating portion 102 of the aerosol-generating article 100.

[0131] In detail, the gas-burning heating element 3' comprises a heating chamber 4' which houses the receiving body 2' and a catalyst member 5' which is connected to the receiving body 2'.

[0132] In this regard, the heating chamber 4' may further comprise at least a lateral wall 4a' and a bottom wall 4b' connected to each other to define a space inside which the receiving body 2' is housed.

[0133] Therefore, the heating chamber 4' may be defined as the portion of the space between the lateral wall 4a' and a bottom wall 4b' and the receiving body 2'.

[0134] The heating chamber 4' may present at least an inlet 6' for the entrance of at least the gas or a mixture of the gas and air.

[0135] Additionally, the heating chamber 4' may present at least an outlet 7' for the exit of exhausted gas.

[0136] Further, the gas-burning heating element 3' comprises a catalyst member 5' arranged in proximity of a central portion 2c' of the receiving body 2'. According to a first example (see Figs. 3), the catalyst member 5' may be arranged inside the heating chamber 4'.

[0137] Specifically, the catalyst member 5' may be arranged in contact with the receiving body 2'. Preferably, the catalyst member 5' may be in contact with the central portion 2c' of the receiving body 2 '.

[0138] More specifically, the catalyst member 5' is arranged around the circumference of the receiving body 2’.

[0139] Preferably, the catalyst member 5' is shaped as a tubular element.

[0140] Preferably, the catalyst member 5' may be in contact with a lateral wall 4a' of the heating chamber 4'.

[0141] Additionally, the catalyst member 5' may be a sponge-like body.

[0142] For example, the catalyst member 5 may be made with one of vanadium phosphorus oxide (VPO), VOx / MgO-γAl2O3, Ni-Mo / Al2O3, palladium (Pd), platinum (Pt), or a combination thereof.

[0143] The catalyst member 5' may have a non-uniform density along a direction parallel to the longitudinal direction of the receiving body 2’.

[0144] Further, the ratio of the volume of the catalyst member 5' to the total volume of the heating chamber 4' may be preferably 0.05% to 20%.

[0145] With specific reference to the first example disclosed in Fig.

[0146] 3, the inlet 6' of the heating chamber 4' introduces a mixture of gas and air.

[0147] In this regard, the aerosol-generating device 1' may comprise a tank 9' for the containment of gas, for example butane gas, and a gas duct 10'. The tank 9' may comprise a fill nozzle 16' to fill the tank 9' with gas.

[0148] Additionally, the aerosol-generating device 1' may comprise an air duct 11' for the introduction of air. Both the gas duct 10' and the air duct 11' join to a carburettor 12'.

[0149] The carburettor 13' may be configured to mix the gas coming from the tank 9' through the gas duct 10' with the air coming from the outside through the air duct to create the mixture.

[0150] A mixture duct 13' extends from the carburettor 12' to inlet 6' of the heating chamber 4' to deliver the mixture thereto.

[0151] According to the variation shown in Fig. 4, the heating chamber 4' may comprise a plurality of inlets 6 for the entrance of the gas, air and / or a mixture of gas and air.

[0152] A valve (not illustrated) may be provided to regulate the opening and closing of the gas flow. The valve may be arranged for example along the gas duct 10'.

[0153] Additionally, an ignition member (not shown) may be provided to initiate the combustion reaction. For example, the ignition member may comprise a piezoelectric element arranged downstream the carburettor 12', for example along the mixture duct 13' or inside the heating chamber 4'.

[0154] An ignition switch 14' may be provided to activate the ignition member and / or the valve.

[0155] In the first example, the inlet 6' may be located at the closed end 2a' of the receiving body 2' and the outlet 7' may be located in proximity of the open end 2b' of the receiving body 2'. Therefore, the gas flows in a direction from the closed end 2a' to the open end 2b' of the receiving body 2'.

[0156] In the variation of Fig. 4, the inlets 6' may be located in the proximity of the open end 2b' of the receiving body 2' and the outlet 7' may be located at the closed end 2a' of the receiving body 2'.

[0157] Therefore, the gas flows in a direction from the open end 2b' to the closed end 2a' of the receiving body 2'.

[0158] With specific reference to the second example shown in Fig. 5, the catalyst member 5' may be arranged outside the heating chamber 4' preferably immediately upstream of the central portion 2c' of the receiving body 2' along a gas flow.

[0159] In use, when the aerosol-generating article 100 is inserted into the receiving body 2', the catalyst member 5' may be arranged immediately upstream of aerosol-generating portion 102.

[0160] In this case, the inlet 6 may be located in proximity of the open end 2b' of the receiving body 2' and the outlet 7' may be located at the closed end 2a' of the receiving body 2'.

[0161] Preferably, the catalyst member 5' is arranged at the inlet 6'.

[0162] Still with reference to the second example of Fig. 5, the receiving body 2' is cylindrical-shaped and may present a helicoidal groove on an external surface of a lateral wall 2L' thereof.

[0163] The following are further examples of an aerosol-generating device which are not part of the present invention.

[0164] Example 1. An aerosol-generating device (1') comprising: a receiving body ( 2 ' ) configured to receive an aerosolgenerating article ( 100 ) and having a closed end ( 2a' ) and an open end ( 2b' ), opposed to the closed end ( 2a' ) configured to insert the aerosol-generating article ( 100 );

[0165] a gas-burning heating element ( 3 ' ) to heat the receiving body ( 2 ' );

[0166] wherein the gas-burning heating element ( 3 ' ) comprises a heating chamber ( 4 ' ) housing the receiving body ( 2 ' ) and a catalyst member ( 5 ' ) arranged in proximity of a central portion ( 2c' ) of the receiving body ( 2 ' ).

[0167] Example 2. The aerosol-generating device (1') according to Example 1, wherein the catalyst member ( 5 ' ) is arranged inside the heating chamber ( 4 ' ).

[0168] Example 3. The aerosol-generating device ( 1 ' ) according to Example 2, wherein the catalyst member ( 5 ' ) is arranged in contact with the receiving body ( 2 ' ).

[0169] Example 4. The aerosol-generating device ( 1 ' ) according to Example 3, wherein the receiving body ( 2 ' ) is cylindricalshaped, and the catalyst member ( 5 ' ) is arranged around the circumference of the receiving body ( 2 ' ).

[0170] Example 5. The aerosol-generating device ( 1 ' ) according to any one of Examples 2 to 4, wherein the catalyst member ( 5 ' ) is in contact with a lateral wall ( 4a' ) of the heating chamber ( 4 ' ).

[0171] Example 6. The aerosol-generating device ( 1 ' ) according to any one of Examples 1 to 5, wherein the heating chamber ( 4 ' ) presents at least an inlet ( 6 ' ) for the entrance of at least the gas and an outlet ( 7 ’ ) for the exit of exhausted gas; the inlet ( 6 ' ) being located at the closed end ( 2a' ) of the receiving body ( 2 ' ) and the outlet ( 7 ’ ) being located in proximity of the open end ( 2b' ) of the receiving body ( 2 ' ). Example 7. The aerosol-generating device ( 1 ' ) according to any one of Examples 1 to 5, wherein the heating chamber ( 4 ' ) presents an inlet ( 6 ' ) for the entrance of the gas and an outlet ( 7 ’ ) for the exit of exhausted gas; the inlet ( 6 ' ) being located in proximity of the open end ( 2b' ) of the receiving body ( 2 ' ) and the outlet ( 7 ’ ) being located at the closed end ( 2a' ) of the receiving body ( 2 ' ).

[0172] Example 8. The aerosol-generating device ( 1 ' ) according to Example 6 or 7, further comprising a plurality of inlets ( 6 ' ) for the entrance of the gas, air and / or a mixture of gas and air.

[0173] Example 9. The aerosol-generating device ( 1 ' ) according to any one of Examples 2 to 8, wherein the catalyst member ( 5 ' ) has a non-uniform density along a direction parallel to the longitudinal direction of the receiving body ( 2 ' ).

[0174] Example 10. The aerosol-generating device ( 1 ' ) according to any one of Examples 2 to 9, wherein the ratio of the volume of the catalyst member ( 5 ' ) to the total volume of the heating chamber ( 4 ' ) is 0. 05 % to 20 %.

[0175] Example 11. The aerosol-generating device ( 1 ' ) according to Example 1, wherein the catalyst member ( 5 ' ) is arranged outside the heating chamber ( 4 ' ) immediately upstream of the central portion ( 2c' ) of the receiving body ( 2 ' ) along a gas flow.

[0176] Example 12. The aerosol-generating device ( 1 ) according to Example 11, wherein the heating chamber ( 4 ' ) presents an inlet ( 6 ' ) for the entrance of the gas and an outlet ( 7 ’ ) for the exit of the exhausted gas; the inlet ( 6 ) being located in proximity of the open end ( 2b' ) of the receiving body ( 2 ' ) and the outlet ( 7 ' ) being located at the closed end ( 2a' ) of the receiving body ( 2 ' ). Example 13. The aerosol-generating device ( 1' ) according to Example 12, wherein the catalyst member (5' ) is arranged at the inlet ( 6' ).

[0177] Example 14. The aerosol-generating device ( 1' ) according to any one of Examples 11 to 13, wherein the receiving body (2' ) is cylindrical-shaped and presents a helicoidal groove ( 8' ) on an external surface of a lateral wall (2L') thereof.

[0178] Example 15. The aerosol-generating device ( 1' ) according to any one of Examples 1 to 14, wherein the catalyst member (5' ) is made with one of vanadium phosphorus oxide (VPO), VOx / MgO-γAl2O3, Ni-Mo / Al2O3, palladium (Pd), platinum (Pt), or a combination thereof.

[0179] Example 16. The aerosol-generating device ( 1' ) according to any one of Examples 1 to 15, wherein the aerosol-generating article ( 100) comprises at least a filter portion ( 101 ) and an aerosol-generating portion ( 102 ) connected to the filter portion ( 101 ) and having a first end ( 102a) proximal to the filter portion ( 101 ) and a second end ( 102b) distal from the filter portion ( 101 ); wherein, in use, when the aerosolgenerating article ( 100) is received in the receiving body (2' ), the first end ( 102a) is configured to be located at the central portion (2c' ) of the receiving body (2' ).

[0180] Naturally, the description set forth herein above concerning embodiments and examples that apply the principles recognized by the inventors is provided solely by way of example of these principles and is therefore not to be understood as a limitation of the scope of the invention claimed herein. Thus, although detailed embodiments and examples have been described, they only serve to provide a better understanding of the invention defined by the independent claims and are not to be seen as limiting.

Claims

Claims1. An aerosol-generating device ( 1 ) comprising:a receiving body (2 ) having a longitudinal axis and configured to receive an aerosol-generating article ( 100) and having a closed end (2a) and an open end (2b), opposed to the closed end (2a) configured to insert the aerosol-generating article ( 100);a gas-burning heating element (3) to heat the receiving body ( 2 );wherein the gas-burning heating element (3) comprises a heating chamber (4 ) housing the receiving body (2 ) and a catalyst member (5) connected to the receiving body (2 );wherein the receiving body (2 ) presents a heat transfer member to transfer heat from the catalyst member (5) to a central portion (2c) of the receiving body (2 );wherein the receiving body (2 ) has an external truncated cone shape along the longitudinal axis thereof.

2. The aerosol-generating device ( 1 ) according to claim 1, wherein the catalyst member (5) is arranged in proximity of the closed end (2a) of the receiving body (2 ).

3. The aerosol-generating device ( 1 ) according to claim 2, wherein the heat transfer member comprises a groove ( 8 ) located on an external surface of a lateral wall (2L) of the receiving body (2 ) extending from the closed end (2a) to the central portion (2c) of the receiving body (2 ); wherein preferably the groove ( 8 ) is helical.

4. The aerosol-generating device ( 1 ) according to any one of claims 1 to 3, wherein the receiving body (2 ) has a thickness decreasing from the closed end (2a) to the open end (2b).

5. The aerosol-generating device ( 1 ) according to any one of claims 1 to 4, wherein the receiving body (2 ) has a circular cross section with respect to the longitudinal axis; whereinthe diameter of the circular cross section at the closed end (2a) is greater than the diameter of the circular cross section at the central portion (2c).

6. The aerosol-generating device ( 1 ) according to any one of claims 1 to 5, wherein the receiving body (2 ) comprises an end portion (2d) at the open end (2b) having a constant diameter.

7. The aerosol-generating device ( 1 ) according to any one of claims 1 to 6, wherein the heating chamber (4 ) has a truncated cone shape along a longitudinal axis thereof.

8. The aerosol-generating device ( 1 ) according to any one of claims 1 to 7, wherein the heating chamber (4 ) presents at least an inlet ( 6) for the entrance of at least the gas or a mixture of the gas and air and an outlet (7 ) for the exit of exhausted gas; the inlet ( 6) being located at the closed end (2a) of the receiving body (2 ) and the outlet (7 ) being located at one end of the heating chamber (4 ) opposite the inlet ( 6) along the longitudinal direction.

9. The aerosol-generating device ( 1 ) according to claim 8, wherein the inlet ( 6) is coaxial to the longitudinal axis of the receiving body (2 ).

10. The aerosol-generating device ( 1 ) according to any one of claims 1 to 9, wherein the catalyst member (5) is arranged inside the heating chamber (4 ).

11. The aerosol-generating device ( 1 ) according to any one of claims 1 to 10, wherein the catalyst member (5) is coaxial to the longitudinal axis of the receiving body (2 ).

12. The aerosol-generating device ( 1 ) according to any one of claims 1 to 11, wherein the catalyst member (5) is in contact with the closed end (2a) of the receiving body (2 ).

13. The aerosol-generating device ( 1 ) according to any one of claims 1 to 12, wherein the catalyst member (5) is in contact with a bottom wall (4b) of the heating chamber (4 ).

14. The aerosol-generating device ( 1 ) according to any one of claims 1 to 13, wherein the catalyst member (5) is made with one of vanadium phosphorus oxide (VPO), VOx / MgO-γAl2O3, Ni-Mo / Al2O3, palladium (Pd), platinum (Pt), or a combination thereof.

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