RU2843423C1 - Current collector assembly for carrying a liquid for carrying and inductively heating an aerosol-forming fluid (embodiments), an induction heating assembly (embodiments), an aerosol-generating system and an aerosol-generating article (embodiments) - Google Patents

Abstract

FIELD: aerosol-generating articles.

SUBSTANCE: invention relates to a current collector assembly for carrying a liquid for transferring and inductively heating an aerosol-forming liquid under the effect of an alternating magnetic field. Unit of current-collector comprises a bundle of threads, which in turn comprises at least a plurality of first threads, including first current-collecting material. Along at least part of the parallel bundle belonging to the bundle of threads, the plurality of first threads are arranged in parallel to each other. Invention also relates to an induction heating assembly and an aerosol-generating article, each comprising a current collector assembly. Invention also relates to an aerosol-generating system comprising an aerosol-generating device with inductive heating, an aerosol-generating article for use with the device and an inductive heating assembly.

EFFECT: simplified design.

20 cl, 7 dwg

Description

The present invention relates to a current collector unit for transferring a liquid, intended for transferring and inductively heating a liquid forming an aerosol. The present invention also relates to an inductive heating unit and an aerosol-generating article, each of which comprises a current collector unit. The present invention also relates to an aerosol-generating system comprising an aerosol-generating device with inductive heating and an aerosol-generating article for use with the device.

Generating inhalable aerosols by heating induction heating of aerosol-forming liquids is generally known in the art. For this purpose, a liquid aerosol-forming substrate can be transferred by means of a wick element from a liquid reservoir to a zone outside the reservoir, where it can be evaporated by means of a heater and exposed to an air channel for subsequent extraction in the form of an aerosol. The heater can be an induction heater. In particular, the wick element can be an induction-heated wick element that contains a current-collecting material and is thus capable of performing both functions: capillary and heating. Accordingly, when exposed to an alternating magnetic field, the wick element is heated due to at least one of the eddy currents or magnetic hysteresis losses that are induced in the wick element depending on its magnetic and electrical properties. Accordingly, such a wick element can also be considered as a current collector for transferring liquid or a current collector unit.

There are various configurations of the wick element, such as mesh configurations. However, many of these configurations are complex and therefore labor-intensive to manufacture.

Therefore, it would be desirable to provide a current collector assembly for transferring a liquid, an induction heating assembly, an aerosol generating article, and an aerosol generating system with the advantages of the solution of the prior art while eliminating the disadvantages thereof. In particular, it would be desirable to provide a current collector assembly for transferring a liquid, an induction heating assembly, an aerosol generating article, and an aerosol generating system including a current collector for transferring a liquid, which is simple and inexpensive to manufacture.

According to an aspect of the present invention, a current collector unit for transferring liquid is proposed, intended for transferring and inductively heating a liquid forming an aerosol under the action of an alternating magnetic field. The current collector unit comprises a bundle of threads, wherein the bundle of threads comprises at least a plurality of first threads, including a first current collector material. Along at least a portion of the parallel bundle belonging to the bundle of threads, the plurality of first threads are arranged parallel to each other.

In accordance with the invention, it has been found that a current collector assembly comprising a bundle of threads having a portion of a parallel bundle along at least a portion of its length can be simple and inexpensive to manufacture, particularly in comparison with more complex configurations of the current collector assembly, such as mesh configurations. In essence, such a current collector assembly can be manufactured by tying together a plurality of individual threads into a bundle, arranged at least partially parallel to the bundle of threads, and cutting the bundle of threads to a desired length.

In the context of this document, the term "parallel" refers to a substantially parallel arrangement, including small deviations from a perfectly parallel arrangement of no more than 5 degrees, in particular no more than 2 degrees, preferably no more than 1 degree, more preferably no more than 0.5 degrees. That is, in a part of a parallel bundle, the threads may diverge from each other by no more than 5 degrees, in particular no more than 2 degrees, preferably no more than 1 degree, more preferably no more than 0.5 degrees.

The threads are particularly suitable for transporting liquids, since they provide a capillary effect by their nature. In addition, in a bundle of threads, the capillary effect is further enhanced by the narrow gaps that form between a plurality of threads when they are bundled together. This applies in particular to a part of a parallel bundle belonging to a bundle of threads, along which the capillary effect is constant, since the narrow gaps between the threads along this part do not change. Thus, a part of a parallel bundle is particularly suitable for immersion, at least partially, in a liquid reservoir for the purpose of transporting, by means of the capillary effect, a liquid that forms an aerosol from the liquid reservoir to a region outside the reservoir. There, the transported liquid can evaporate and be exposed to the air channel for extraction in the form of an aerosol.

Preferably, the bundle of threads is a bundle of untwisted threads. In a bundle of untwisted threads, the threads of the bundle of threads run next to each other without crossing each other, preferably along the entire length of the bundle of threads. In particular, in a part of the parallel bundle, the threads run parallel to each other without crossing each other. Similarly, the bundle of threads can comprise a twisted part in which the threads of the bundle of threads are twisted. The twisted part can increase the mechanical stability of the bundle of threads.

Preferably, the plurality of first threads are threads of a hard material. Threads of a hard material are inexpensive and easy to manufacture. In addition, threads of a hard material provide good mechanical stability, which makes the bundle of threads strong.

For the same reasons, the plurality of first threads are preferably threads of the same type of material. Accordingly, the plurality of first threads are preferably made of the first current-collecting material.

Due to the fact that the first threads contain or are made of the first current-collecting material, the bundle of threads is able to perform both functions: transfer and heating of the liquid forming the aerosol. Advantageously, this dual function ensures high cost-effectiveness in terms of materials and a compact design of the current collector unit without separate means for transfer and heating. In addition, there is direct thermal contact between the heat source, i.e. the threads, and the liquid forming the aerosol adhering to the threads. In contrast to the heater in contact with the impregnated wick, direct contact between the threads and a small amount of liquid advantageously ensures instantaneous heating, i.e. a rapid onset of evaporation.

In the context of this document, the term "current-collecting material" means a material that can convert electromagnetic energy into heat when exposed to an alternating magnetic field. This may be the result of at least one of hysteresis losses or eddy currents induced in the current-collecting material, depending on the electrical and magnetic properties. Hysteresis losses occur in ferromagnetic or ferrimagnetic current-collecting materials due to the switching of magnetic domains within the material under the influence of an alternating electromagnetic field. Eddy currents are induced in electrically conductive current-collecting materials. In the case of an electrically conductive ferromagnetic or ferrimagnetic current-collecting material, heat is generated by both eddy currents and hysteresis losses.

Accordingly, the first current-receiving material may be made of any material that can be inductively heated to a temperature sufficient to generate an aerosol from an aerosol-forming substrate. Accordingly, the first current-receiving material may comprise or may be made of a material that is at least one of electrically conductive and ferromagnetic or ferrimagnetic materials, respectively. Thus, the first current-receiving material may comprise or may be made of one of a ferrimagnetic material, or a ferromagnetic material, or an electrically conductive material, or an electrically conductive ferrimagnetic material, or an electrically conductive ferromagnetic material.

For example, the first current collecting material may comprise or be made of one of ferrite, aluminum, iron, nickel, copper, bronze, cobalt, nickel alloy, plain carbon steel, stainless steel, ferritic stainless steel, ferromagnetic stainless steel, martensitic stainless steel, or austenitic stainless steel.

Capillarity or capillary action is generally based on the reduction of surface energy of two separate surfaces, the liquid surface and the solid surface of the filaments. Capillarity or capillary effect involves an effect that depends on the radius of curvature of both the liquid surface and the filaments. Consequently, large surface areas and small radii of curvature may be required, both of which are achieved by the small diameter of the filaments and the brush-like nature of the filament bundle. The radius of curvature of the filaments is important because the liquid wets the filaments.

Accordingly, the plurality of first threads may have a diameter of no more than 0.025 millimeters, no more than 0.05 millimeters, no more than 0.1 millimeters, no more than 0.15 millimeters, no more than 0.2 millimeters, no more than 0.25 millimeters, no more than 0.3 millimeters, no more than 0.35 millimeters, no more than 0.4 millimeters, no more than 0.45 millimeters, or no more than 0.5 millimeters.

On the contrary, the diameter of the first threads preferably has a certain minimum, related to the so-called skin depth. The skin depth is a measure of how deep the electrical conductivity takes place in the electrically conductive current-collecting material during induction heating. In contrast to direct currents, alternating currents mainly flow in the "skin layer" of the electrical conductor between the outer surface of the conductor and a level called the skin depth. The alternating current density is greatest near the surface of the conductor and decreases with greater depth in the conductor. This phenomenon is known as the skin effect, which is mainly due to opposite eddy currents induced by the alternating magnetic field. Preferably, the plurality of first threads have a diameter at least twice the skin depth to induce a sufficient amount of eddy currents and thus to generate a sufficient amount of thermal energy.

In general, the depth of the surface layer depends on the permeability and electrical conductivity of the current-collecting material, as well as on the frequency of the control alternating current or the frequency of the alternating magnetic field, respectively. Preferably, the current-collecting unit is controlled by a high-frequency alternating magnetic field. In the context of this document, the high-frequency electromagnetic field may be in the range from 500 kHz (kilohertz) to 30 MHz (megahertz), in particular from 5 MHz (megahertz) to 15 MHz (megahertz), preferably from 5 MHz (megahertz) to 10 MHz (megahertz).

Depending on the materials and the frequency of the alternating magnetic field used, the plurality of first threads may have a diameter of at least 0.015 millimeters, at least 0.02 millimeters, at least 0.025 millimeters, at least 0.05 millimeters, at least 0.075 millimeters, at least 0.1 millimeters, at least 0.125 millimeters, at least 0.15 millimeters, at least 0.2 millimeters, at least 0.3 millimeters, or at least 0.4 millimeters.

In general, the plurality of first threads may have any cross-sectional shape suitable for the liquid forming the aerosol when they are collected in a bundle. Accordingly, at least one of, in particular each of, the plurality of first threads may have a circular, ellipsoidal, oval, triangular, rectangular, square, hexagonal or polygonal cross-section. Preferably, all first threads have the same cross-section. It is also possible that one or more threads from the plurality of first threads have a cross-section that differs from the cross-sections of one or more other threads from the plurality of first threads. Preferably, the plurality of first threads have a circular, ellipsoidal or oval cross-section. Advantageously, the latter cross-sectional shapes ensure that the threads in the bundle of threads are only in linear contact with each other, but not in area contact. Due to the linear contact between the multiple threads themselves, narrow gaps are formed which facilitate the capillary effect necessary for the transport of the liquid that forms the aerosol.

The surface of the plurality of first threads can be treated. In particular, the plurality of first threads can comprise, at least in part, a surface coating, such as an aerosol-enhancing surface coating, a liquid-attracting surface coating, a liquid-repellent surface coating, or an antibacterial surface coating. The aerosol-enhancing surface coating can advantageously increase the diversity of the user's sensations. The liquid-attracting surface coating can be useful in terms of enhancing the capillary effect of the thread bundle. The antibacterial surface coating can serve to reduce bacterial contamination. The liquid-repellent surface coating, in particular at the end of the threads, can prevent liquid from dripping.

Depending on the available space, the dimensions of the threads and the amount of liquid to be transferred and heated to form the aerosol, the plurality of first threads in the bundle of threads may comprise from 3 to 100 first threads, in particular from 10 to 80 first threads, preferably from 20 to 60 first threads, more preferably from 30 to 50 first threads, for example 40 first threads.

In addition to the plurality of first threads, the bundle of threads may further comprise a plurality of second threads comprising a second current-collecting material, wherein along at least a portion of the parallel bundle belonging to the bundle of threads, the plurality of second threads are arranged parallel to each other and to the plurality of first threads. While the first current-collecting material of the plurality of first threads may be optimized with respect to heat loss and, thus, heating efficiency, the second current-collecting material may be advantageously used as a temperature marker. For this purpose, the second current-collecting material preferably comprises one of a ferrimagnetic material or a ferromagnetic material. In particular, the second current-collecting material is selected in such a way as to have a Curie temperature corresponding to a given heating temperature of the current-collecting unit. The magnetic properties of the second current-collecting material at its Curie temperature change from ferromagnetic or ferrimagnetic to paramagnetic, which is accompanied by a temporary change in its electrical resistance. Thus, by monitoring the corresponding change in the electric current absorbed by the induction source, it is possible to detect when the second current-receiving material has reached its Curie temperature and thus when the set heating temperature has been reached.

Preferably, the first current-collecting material is different from the second current-collecting material.

The second current-collecting material preferably has a Curie temperature that is below 500 degrees Celsius. In particular, the second current-collecting material may have a Curie temperature below 350 degrees Celsius, preferably below 300 degrees Celsius, more preferably below 250 degrees Celsius, even more preferably below 200 degrees Celsius, most preferably below 150 degrees Celsius. Preferably, the Curie temperature is selected so that it is below the boiling point of the liquid forming the aerosol that is to be evaporated, in order to prevent the formation of hazardous components in the aerosol.

Suitable materials for the second current-collecting material may include nickel and certain nickel alloys. Similarly, the second current-collecting material may comprise one of mu-metal or permalloy. In particular, the second current-collecting material may have a relative maximum magnetic permeability of at least 80 or at least 100, more particularly at least 1000, preferably at least 10,000 for frequencies up to 50 kHz and a temperature of 25 degrees Celsius.

In addition, the plurality of second threads may have the same or similar properties as described above with respect to the plurality of first threads.

Accordingly, the plurality of second threads may be threads of a solid material. Moreover, the plurality of second threads may be threads of a single type of material. In particular, the plurality of second threads may be made of a second current-collecting material.

Similarly, the surface of the plurality of second threads can be treated. In particular, the plurality of second threads can comprise a surface coating, such as an aerosol-enhancing surface coating, a liquid-attracting surface coating, a liquid-repellent surface coating, or an antibacterial surface coating.

Moreover, at least one of, in particular each of, the plurality of second threads may have a circular, ellipsoidal, oval, triangular, rectangular, square, hexagonal or polygonal cross-section.

For the same reasons discussed above with respect to the plurality of first threads, the plurality of second threads may have a diameter of at least 0.015 millimeters, at least 0.02 millimeters, at least 0.025 millimeters, at least 0.05 millimeters, at least 0.075 millimeters, at least 0.1 millimeters, at least 0.125 millimeters, at least 0.15 millimeters, at least 0.2 millimeters, at least 0.3 millimeters, or at least 0.4 millimeters. Similarly, the plurality of second threads may have a diameter of no more than 0.025 millimeters, no more than 0.05 millimeters, no more than 0.1 millimeters, no more than 0.15 millimeters, no more than 0.2 millimeters, no more than 0.25 millimeters, no more than 0.3 millimeters, no more than 0.35 millimeters, no more than 0.4 millimeters, no more than 0.45 millimeters, or no more than 0.5 millimeters.

In general, the plurality of first threads and the plurality of second threads may have the same diameter. As a result, the capillary effect and shear rate are the same throughout the entire bundle of threads. Conversely, it is also permissible for the plurality of first threads and the plurality of second threads to have different diameters. Different thread diameters can be used to vary the capillary effect throughout the bundle of threads.

The plurality of second threads in the bundle of threads may comprise from 1 to 100 second threads, in particular from 10 to 80 second threads, preferably from 20 to 60 second threads, more preferably from 30 to 50 second threads, for example 40 second threads.

In general, the number of first threads may be the same as the number of second threads. However, it is also permissible for the number of first threads to differ from the number of second threads. In particular, the number of first threads may be greater, for example, by two or three times, or four times, or five times, or six times, or seven times, or eight times, or nine times, or ten times, than the number of second threads. This applies in particular to cases where the second threads are used as temperature generators, for which a small number of second threads is sufficient.

The total number of threads in the bundle of threads may be in the range from 3 to 100 threads, in particular from 10 to 80 threads, preferably from 20 to 60 threads, more preferably from 30 to 50 threads, for example 40 threads.

The plurality of first threads and the plurality of second threads may be substantially uniformly distributed over the bundle of threads. The uniform distribution may maintain a uniform capillary effect over the entire bundle of threads. Alternatively, it is also allowed for the plurality of first threads and the plurality of second threads to be non-uniformly distributed over the bundle of threads. For example, the plurality of second threads may be located (exclusively) inside the central portion of the bundle of threads surrounded by the plurality of first threads. That is, the plurality of second threads may form the core portion of the bundle of threads, and the plurality of first threads may form the outer portion of the bundle of threads surrounding the core portion. Such a configuration may be advantageous in the case where the transport and heating function of the bundle of threads is mainly provided by the plurality of first threads, while the plurality of second threads serves only as a temperature marker. Conversely, the plurality of first threads may be located (exclusively) inside the central portion of the bundle of threads surrounded by the plurality of second threads. That is, a plurality of first threads may form a core portion of the thread bundle, and a plurality of second threads may form an outer portion of the thread bundle surrounding the core portion. Similarly, a plurality of first threads may be located in a first portion, in particular in a first half of the thread bundle, while a plurality of second threads may be located in a second portion, in particular in a second half of the thread bundle adjacent to the first portion, in particular to the first half. Such a configuration is particularly easy to manufacture. Alternatively, a plurality of second threads may be distributed randomly throughout the thread bundle. In addition, it is allowed that the length of a plurality of second threads may differ from the length of a plurality of first threads. In particular, the length of a plurality of second threads may be shorter than the length of a plurality of first threads. And vice versa, the length of a plurality of second threads may be greater than the length of a plurality of first threads.

In the parallel bundle portion, the average center-to-center distance between adjacent first threads and, if any, second threads is no more than 0.025 millimeters, no more than 0.05 millimeters, no more than 0.1 millimeters, no more than 0.15 millimeters, no more than 0.2 millimeters, no more than 0.25 millimeters, no more than 0.3 millimeters, no more than 0.35 millimeters, no more than 0.4 millimeters, no more than 0.45 millimeters, or no more than 0.5 millimeters. These center-to-center distance values are particularly suitable for ensuring a sufficient capillary effect.

As mentioned above, one section of the thread bundle can be designed to be immersed in a liquid reservoir: This section can be designated as an impregnation section and can be located at one end of the thread bundle. From there, the aerosol-forming liquid is transferred to another section of the thread bundle, located outside the reservoir, in particular at the other end of the thread bundle. There, the transferred liquid can be evaporated by means of induction heating and exposed to the air channel for extraction in the form of an aerosol. Accordingly, this section can be designated as a heating section. During use, the heating section is heated to temperatures sufficient for evaporation of the aerosol-forming liquid, while the impregnation section should preferably remain at temperatures significantly below the evaporation temperature in order to avoid boiling of the aerosol-forming liquid in the liquid reservoir. Accordingly, during use, the thread bundle has a temperature profile along its entire length with sections of higher and lower temperatures. In particular, the bundle of threads may have a temperature profile that reflects an increase in temperature from the impregnation area to the heating area, in particular from temperatures below the evaporation temperature to temperatures above the corresponding evaporation temperature.

In the context of this document, the term "heating section" means a section of the current collector assembly that is capable of being exposed to an alternating magnetic field to evaporate the aerosol-forming liquid for the purpose of inductive heating. Similarly, the term "impregnation section" means a section of the current collector assembly that is capable of being immersed in a liquid reservoir.

The temperature profile actually formed when using the current collector unit depends, among other things, on the thermal conductivity and the length of the filament bundle. A sufficient temperature gradient between the impregnation section and the heating section of the filament bundle requires a certain distance between the impregnation section and the heating section. Consequently, a certain total length of the filament bundle is necessary so that the temperature in the impregnation section is below the evaporation temperature.

Accordingly, the total length of the bundle of threads may be in the range of from 5 to 50 millimeters, in particular from 10 to 40 millimeters, preferably from 10 to 30 millimeters, more preferably from 10 to 20 millimeters.

The bundle of threads may further comprise a branched portion at least at one end portion of the bundle of threads, wherein the plurality of first threads and, if present, the plurality of second threads diverge from each other. Such a branched portion may be useful for facilitating the action of the evaporated liquid forming the aerosol on the air channel and, thus, for facilitating the formation of the aerosol. It is assumed that the bundle of threads may comprise two branched portions, one at each end portion of the bundle of threads.

At least at one end portion, the bundle of threads may further comprise a tapering portion, in which the length of the threads gradually decreases from the center to the outer portion of the bundle. The tapering portion may have the shape of a sharpened pencil. The tapering portion may be obtained, for example, by cutting the threads at at least at one end portion of the bundle of threads at an angle. The geometry of the tip of the tapering portion may facilitate the removal of the evaporating liquid that forms the aerosol. In addition, the tapering portion may actively facilitate the transfer of liquid by aligning the external air flow in the tapering portion with the geometry of the tip in such a way as to create a pressure difference in accordance with the Bernoulli principle.

Preferably, the heating section of the bundle of threads is located at least partially near the branched portion, in particular at least partially overlaps the branched portion.

The branched portion may have a length of not less than 5 percent, 10 percent, 20 percent, or 30 percent of the total length of the bundle of threads. Conversely, the branched portion may have a length of not more than 10 percent, 20 percent, 30 percent, 40 percent, or 50 percent of the total length of the bundle of threads.

Similarly, the portion of the parallel bundle may have a length of not less than 5 percent, 10 percent, 20 percent, 30 percent, 40 percent, 50 percent, 60 percent, 70 percent or 80 percent of the total length of the bundle of threads. Conversely, the portion of the parallel bundle may have a length of not more than 10 percent, 20 percent, 30 percent, 40 percent, 50 percent, 60 percent, 70 percent, 80 percent, 90 percent or 100 percent of the total length of the bundle of threads. In the latter case, when the portion of the parallel bundle has a length of 100 percent of the total length of the bundle of threads, the portion of the parallel bundle extends entirely along the bundle of threads. Accordingly, in this configuration, the bundle of threads does not contain branched portions.

Preferably, the impregnation section of the bundle of threads is located at least partially near a part of the parallel bundle, in particular, at least partially overlaps the part of the parallel bundle.

A portion of the parallel bundle may be located, at least partially, at one end portion of the bundle of threads. In this configuration, a portion of the parallel bundle may be used to implement an impregnation section at one end of the bundle of threads.

Alternatively, a portion of the parallel bundle may be located between two ends of the bundle of threads, for example, between two branched portions. In particular, a portion of the parallel bundle may be located symmetrically between two ends of the bundle of threads, for example, between two branched portions. In this configuration, the bundle of threads may have two branched portions, one at each end portion of the bundle of threads. In particular, this configuration may be used to implement either two heating sections or two impregnation sections at each end portion of the bundle of threads. Alternatively, in this configuration, one end portion may be an impregnation section, while the other end portion may be a heating section. The portion of the parallel bundle may be located, in particular, symmetrically between any of these sections.

In order to hold the threads together in a parallel configuration, at least partially, a portion of the parallel bundle may be assembled into a bundle by means of a sleeve, a bushing or a tow. The sleeve or bushing or the tow may comprise a component in the form of a shell. For example, the bushing may be a dividing wall separating the liquid reservoir from the evaporation zone. Similarly, at least partially, a portion of the parallel bundle may be connected by a gasket or a sealing ring. The threads may be held together by crimping or multi-component molding, i.e. by means of a crimping element or a molded element. It is also possible for the threads to be held together by welding them together at one end of the thread bundle, preferably at the end of the impregnation section. In this configuration, the capillary effect also occurs along the unwelded portion of the thread bundle.

In general, the bundle of threads may be a rectilinear bundle of threads, that is, essentially a straight, unbent or uncurved bundle of threads. Such a configuration does not exclude a small bend in the bundle of threads, that is, large radii of curvature along the entire length of the bundle of threads. In use, large radii of curvature may include radii of curvature that are 10 times, in particular 20 times, or 50 times, or in particular 100 times, the total length of the bundle of threads.

Alternatively, the bundle of threads may be a curved bundle of threads, i.e. the bundle of threads may be curved along its entire length. In this configuration, the bundle of threads may have a radius of curvature in the range of 0.5/Pi to 10 times, in particular 1/Pi to 5 times, or 2/Pi to 2 times the total length of the bundle of threads. Here, Pi denotes Archimedes' constant, i.e. the ratio of the circumference to the diameter of a circle.

In general, when viewed in a cross-section perpendicular to the length of the bundle of threads, the bundle of threads can have any cross-sectional shape. In particular, at least along a part of the parallel bundle, the bundle of threads can have a circular, ellipsoidal and oval, triangular, rectangular, square, hexagonal or polygonal cross-section. In particular, circular cross-sections are easy to implement. The cross-sectional shape at least along a part of the parallel bundle can be easily implemented by means of a corresponding opening of the sleeve, bushing or strand used to tie the threads.

According to another aspect of the present invention, an induction heating unit for transferring and inductively heating a liquid forming an aerosol is presented. The heating unit comprises at least one current collector unit for transferring the liquid according to the present invention and as described herein. The heating unit further comprises at least one induction source, designed and arranged with the possibility of generating an alternating magnetic field in the heating section of at least one current collector unit for transferring the liquid, in particular in the heating section of the bundle of threads.

For generating an alternating magnetic field, the induction source may comprise at least one inductor, preferably at least one induction coil. Preferably, the induction coil is arranged at least around the heating section of the current collector unit for transporting liquid, in particular at least around the heating section of the bundle of filaments.

At least one induction coil may be a helical coil or a flat planar coil, in particular a disk coil or a curved planar coil. The use of a flat helical coil provides a compact design that is reliable and inexpensive to manufacture. The use of a helical induction coil advantageously provides the generation of a uniform alternating magnetic field. In this context, a "flat helical coil" means a coil that is generally flat, where the winding axis of the coil is perpendicular to the plane in which the coil lies. A flat helical induction coil may have any desired shape in the plane of the coil. For example, a flat helical coil may have a round shape or may have a generally oblong or rectangular shape. However, the term "flat helical coil" in the context of this document covers both coils that are planar and flat helical coils whose shape corresponds to a curved surface. For example, the induction coil may be a "curved" planar type coil arranged around the circumference of a preferably cylindrical coil holder, such as a ferrite core. In addition, the flat spiral coil may comprise, for example, two layers of a four-turn flat spiral coil or one layer of a four-turn flat spiral coil.

At least one induction coil may be retained within one of the heating unit housing, or the main portion, or the housing of the aerosol generating device that contains the heating unit.

As further described above with respect to the current collector assembly, the heating section of the current collector assembly for transferring liquid, in particular the heating section of the bundle of threads, can be located at one end portion of the bundle of threads. This configuration can advantageously prevent boiling of the liquid forming the aerosol, in case the bundle of threads comprises an impregnation section at the opposite end portion.

The length of the heating section can be selected to generate the desired amount of aerosol. The shorter the heating section, the less liquid that forms the aerosol evaporates and, therefore, less aerosol is generated. Accordingly, the heating section of the bundle of filaments can have a length of at least 5 percent, 10 percent, 20 percent, 30 percent, 40 percent, 50 percent, 60 percent, 70 percent or 80 percent of the total length of the bundle of filaments. Similarly, the heating section of the bundle of filaments can have a length of at most 10 percent, 20 percent, 30 percent, 40 percent, 50 percent, 60 percent, 70 percent, 80 percent, 90 percent or 100 percent of the total length of the bundle of filaments.

The bundle of threads can be located with an offset from the center relative to the axis of symmetry of the alternating magnetic field generated by the induction source when using the heating unit. Preferably, due to the offset from the center location, i.e. the asymmetric location, the bundle of threads is located in the zone of the alternating magnetic field having a higher field density compared to the symmetric location relative to the center. As a result, the heating efficiency is predominantly increased.

The induction source may comprise an alternating current (AC) generator. The AC generator may be powered by a power source of the aerosol generating device. The AC generator is operatively connected to at least one induction coil. In particular, at least one induction coil may be an integral part of the AC generator. The AC generator is configured to generate a high-frequency oscillating current to pass through at least one induction coil to generate an alternating magnetic field. The alternating current may be supplied to at least one induction coil continuously after activation of the system or may be supplied intermittently, for example, from puff to puff.

Preferably, the induction source comprises a DC to AC converter connected to a DC power source comprising an LC circuit, wherein the LC circuit comprises a series connection of a capacitor and an inductor.

The induction source is preferably designed to generate a high-frequency magnetic field. In the context of this document, the high-frequency magnetic field may exist in the range from 500 kHz (kilohertz) to 30 MHz (megahertz), in particular from 5 MHz (megahertz) to 15 MHz (megahertz), preferably from 5 MHz (megahertz) to 10 MHz (megahertz).

The heating unit may further comprise a controller adapted to control the operation of the heating unit. In particular, the controller may be configured to control the operation of the induction source, preferably in a feedback configuration, to control the heating of the aerosol-forming liquid to a predetermined operating temperature. The operating temperature used to heat the aerosol-forming liquid may be in the range from 100 degrees Celsius to 300 degrees Celsius, in particular from 150 degrees Celsius to 250 degrees Celsius, such as 230 degrees Celsius. These temperatures are typical operating temperatures for heating, but not burning, the aerosol-forming substrate.

The controller may comprise a microprocessor, such as a programmable microprocessor, a microcontroller, or an application-specific integrated circuit (ASIC), or other electronic circuit capable of providing control. The controller may comprise additional electronic components, such as at least one DC-AC converter and/or power amplifiers, such as a class C power amplifier or a class D power amplifier, or a class E power amplifier. In particular, the inductive source may be part of the controller.

The controller may be a main controller, or a part thereof, of an aerosol generating device of which the heating unit according to the present invention is a part.

The heating unit may comprise a power source, in particular a DC power source configured to provide a DC supply voltage and a DC current for the induction source. Preferably, the power source is a battery, such as a lithium iron phosphate battery. Alternatively, the power source may be a charge storage device of another type, such as a capacitor. The power source may require recharging, i.e. the power source may be rechargeable. The power source may have a capacity that allows storing sufficient energy for one or more uses by the user. For example, the power source may have a sufficient capacity to enable continuous aerosol generation for a period of approximately six minutes, or for a period that is a multiple of six minutes. In another example, the power source may have a capacity sufficient to enable a predetermined number of puffs or individual activations of the induction source. The power source may be the main power source of the aerosol generating device, of which the heating unit according to the present invention is a part.

The heating unit may further comprise a flow concentrator located around at least a portion of the induction coil and configured to distort the alternating magnetic field of at least one induction source toward the bundle of filaments, in particular toward the heating section of the bundle of filaments when using the heating unit. The flow concentrator preferably comprises a flow concentrator foil, in particular a multilayer flow concentrator foil.

Additional features and advantages of the heating assembly according to the present invention have already been described in relation to the current collector assembly according to the present invention and are thus equally applicable.

According to the present invention, there is also provided an aerosol-generating article intended for use with an aerosol-generating device with induction heating. The article comprises at least a first liquid reservoir for storing a first aerosol-generating liquid, wherein the first liquid reservoir comprises an outlet. The article further comprises at least a first current collector assembly for transferring liquid according to the present invention and as described herein. The first current collector assembly for transferring liquid comprises a first bundle of threads for delivering the first aerosol-generating liquid from the first liquid reservoir through the outlet to a zone outside the first liquid reservoir.

In the context of this document, the term "aerosol generating article" refers to a consumable part intended for use with an aerosol generating device with induction heating, in particular to a consumable part that is to be disposed of after a single use. For example, the article may be a cartridge that is inserted into an aerosol generating device with induction heating. Preferably, the aerosol generating article comprises at least a first aerosol-forming liquid that is intended to be heated rather than burned and that, when heated, releases volatile compounds that can form an aerosol.

Preferably, the first bundle of threads comprises at least one impregnation section located in the first liquid reservoir.

The length of the impregnation section can be advantageously used to control the amount of aerosol-forming liquid that is to be absorbed and transferred from the liquid reservoir. Accordingly, at least one impregnation section of the first bundle of threads can have a length of no more than 10 percent, no more than 20 percent, no more than 30 percent, no more than 40 percent, no more than 50 percent or no more than 60 percent of the total length of the first bundle. And vice versa, at least one impregnation section of the first bundle of threads can have a length of no less than 10 percent, no less than 20 percent, no less than 30 percent, no less than 40 percent, no less than 50 percent or no less than 60 percent of the total length of the first bundle of threads. In particular, at least one impregnation section of the first bundle of threads can have a length of 10 percent, 20 percent, 30 percent, 40 percent, 50 percent or 60 percent of the total length of the first bundle of threads.

As further described above with respect to the current collector assembly, the impregnation section of the first bundle of threads may be located at one end portion of the first bundle of threads. In this configuration, the first bundle of threads may comprise a heating section at the opposite end portion of the first bundle of threads.

In a similar manner, the impregnation section of the first bundle of threads can be located between the two ends of the first bundle of threads. In this configuration, both end portions of the bundle of threads can be used as heating sections. For example, the first bundle of threads can be curved, in particular have a U-shaped, V-shaped or C-shaped form, wherein the impregnation section forms, at least in part, the base of the U-shaped, V-shaped or C-shaped bundle of threads.

It is also possible for the first bundle of threads to comprise two impregnation sections, each of which is located in the first liquid reservoir. Preferably, the two impregnation sections may be located at the end portions of the first bundle of threads, one at each end portion. In this configuration, the first bundle of threads may also be curved, in particular U-shaped, V-shaped or C-shaped, wherein each of the two impregnation sections forms, at least partially, a section of the first bundle of threads of a U-shaped, V-shaped or C-shaped form.

The aerosol-generating article may further comprise at least a second liquid reservoir for storing a second aerosol-forming liquid, wherein the second liquid reservoir comprises an outlet. Furthermore, the aerosol-generating article may comprise at least a second current collector assembly for transferring liquid according to the present invention and as described herein, wherein the second current collector assembly for transferring liquid comprises a second bundle of threads for delivering the second aerosol-forming liquid from the second liquid reservoir through the outlet into a zone outside the second liquid reservoir. The presence of more than one liquid reservoir may be used to increase the variety of user sensations with respect to at least one of taste, duration of sensation and aerosol composition.

As described above with respect to the second bundle of threads, the second bundle of threads may also comprise at least one impregnation section which is located in the second liquid reservoir. Furthermore, at least one impregnation section of the second bundle of threads may have a length of no more than 10 percent, no more than 20 percent, no more than 30 percent, no more than 40 percent, no more than 50 percent or no more than 60 percent of the total length of the second bundle. And vice versa, at least one impregnation section of the second bundle of threads may have a length of no less than 10 percent, no less than 20 percent, no less than 30 percent, no less than 40 percent, no less than 50 percent or no less than 60 percent of the total length of the second bundle of threads. In particular, at least one impregnation section of the second bundle of threads may have a length of 10 percent, 20 percent, 30 percent, 40 percent, 50 percent or 60 percent of the total length of the second bundle of threads.

As further described above with respect to the first bundle of threads, the impregnation section of the second bundle of threads may be located at one end portion of the second bundle of threads. In this configuration, the second bundle of threads may comprise a heating section at the opposite end portion of the first bundle of threads.

In a similar manner, the impregnation section of the second bundle of threads can be located between the two ends of the second bundle of threads. Accordingly, the second bundle of threads can be curved, in particular U-shaped, V-shaped or C-shaped, wherein the impregnation section forms, at least in part, the base of the U-shaped, V-shaped or C-shaped bundle of threads.

It is also possible for the second bundle of threads to comprise two impregnation sections, each of which is located in the second liquid reservoir. Preferably, the two impregnation sections can be located at the end portions of the second bundle of threads, one at each end portion. In this configuration, the second bundle of threads can also be curved, in particular have a U-shaped, V-shaped or C-shaped form, wherein each of the two impregnation sections forms, at least partially, a section of the second bundle of threads of a U-shaped, V-shaped or C-shaped form.

The aerosol-generating article may be a disposable aerosol-generating article or a reusable aerosol-generating article. In the latter case, the aerosol-generating article may be refillable. That is, the first reservoir and, if present, the second reservoir may be refillable with the first aerosol-generating liquid and the second aerosol-generating liquid, respectively. In any configuration, the aerosol-generating article may further comprise the first aerosol-generating liquid contained in the first liquid reservoir. Similarly, the aerosol-generating article may further comprise the second aerosol-generating liquid contained in the second liquid reservoir.

In order to increase the diversity of the user's sensations, the first aerosol-generating liquid may be different from the second aerosol-generating liquid. As an example, the first aerosol-generating liquid may be a water-based aerosol-generating liquid, and the second aerosol-generating liquid may be an oil-based aerosol-generating liquid. It is also possible that the first aerosol-generating liquid and the second aerosol-generating liquid are the same liquid. In this configuration, the first aerosol-generating liquid and the second aerosol-generating liquid may evaporate alternately to expand the user's sensations with respect to a single aerosol-generating product.

As used herein, the term "aerosol-forming liquid" refers to a liquid capable of releasing volatile compounds that can form an aerosol when the aerosol-forming liquid is heated. The aerosol-forming liquid may contain both solid and liquid aerosol-forming material or components. The aerosol-forming liquid may contain a tobacco-containing material that contains volatile tobacco flavor compounds that are released from the liquid when heated. Alternatively or additionally, the aerosol-forming liquid may contain a non-tobacco material. The aerosol-forming liquid may further contain an aerosol-forming agent. Examples of suitable aerosol-forming agents include glycerin and propylene glycol. The aerosol-forming liquid may also contain other additives and ingredients, such as nicotine or flavoring agents. In particular, the aerosol-forming liquid may contain water, solvents, ethanol, plant extracts, and natural or artificial flavors. The aerosol-forming liquid may be a water-based aerosol-forming liquid or an oil-based aerosol-forming liquid.

In addition, the article may comprise a mouthpiece. In the context of this document, the term "mouthpiece" means the part of the device that is placed in the user's mouth for direct inhalation of the aerosol from the article. Preferably, the mouthpiece comprises a filter. The filter can be used to filter out unwanted components of the aerosol. The filter may also comprise additional material, such as a flavoring material, added to the aerosol.

The article may have a simple structure. The article may have a housing comprising a first liquid reservoir and, if present, a second liquid reservoir. The housing is preferably a rigid housing consisting of a liquid-impermeable material. As used herein, "rigid housing" means a housing that is self-supporting. The housing may comprise or be made of one of PEEK (polyetheretherketone), PP (polypropylene), PE (polyethylene) or PET (polyethylene terephthalate). PP, PE and PET are particularly economical and easy to mold, in particular extrude. The aerosol-forming substrate is a substrate that can release volatile compounds that can form an aerosol. The housing may also comprise flexible sections or folded sections. The housing may further comprise at least one vent for volume compensation.

Additional features and advantages of the aerosol generating article according to the present invention have already been described in relation to the current collector assembly according to the present invention and are thus equally applicable.

According to the present invention, there is provided an aerosol generating system comprising an aerosol generating device with induction heating, an aerosol generating article for use with the aerosol generating device, and an induction heating unit according to the present invention and as described herein. The induction source of the heating unit may be part of the aerosol generating device with induction heating, and the current collector unit for transferring liquid of the heating unit may be part of the aerosol generating article. In other words, an aerosol generating system is also provided, comprising an aerosol generating device with inductive heating and an aerosol generating article for use with the aerosol generating device, wherein the article comprises at least one current collector assembly for transferring liquid according to the present invention and as described herein, and wherein the device comprises at least one inductive source, designed and arranged with the possibility of generating an alternating magnetic field in the heating section of at least one current collector assembly for transferring liquid of the article, in particular in the heating section of the bundle of filaments, when the article is used with the device. In particular, the at least one inductive source can be an inductive source as described above in relation to the inductive source of the inductive heating unit according to the present invention. At least one inductive source of the aerosol generating device and at least one current collector assembly for transferring liquid of the aerosol generating article can together form an inductive heating unit according to the present invention and as described herein. If present, the controller of the heating unit may be part of the aerosol generating device, in particular located in the aerosol generating device. Preferably, the controller of the aerosol generating device may comprise or may be a controller of the heating unit. In particular, the aerosol generating device may comprise a controller as described above with respect to the induction source of the induction heating unit according to the present invention.

Similarly, if present, the power supply of the heating unit may be part of the aerosol generating device, in particular located in the aerosol generating device. Preferably, the power supply of the aerosol generating device may comprise or may be a power supply of the heating unit. In particular, the aerosol generating device may comprise a power supply as described above with respect to the induction source of the induction heating unit according to the present invention.

In the context of the present document, the term "aerosol generating device" is used to describe an electrical device capable of interacting with at least one aerosol generating article containing at least one aerosol generating liquid, for example, to generate an aerosol by inductively heating a susceptor unit, and thus with an aerosol generating liquid in the article. Preferably, the aerosol generating device is a puffing device for generating an aerosol directly inhaled by the user through the mouth. In particular, the aerosol generating device is a hand-held aerosol generating device.

The aerosol generating device may comprise a receiving cavity for removably receiving at least a portion of the aerosol generating article.

The induction coil of the induction source can be arranged with the possibility of surrounding at least part of the receiving cavity, in particular surrounding at least part of the bundle of threads of the aerosol-generating article, in particular the heating section of the bundle of threads when the aerosol-generating article enters the receiving cavity.

In addition to the specific configuration of the susceptor assembly of the heating assembly, the aerosol generating article of the aerosol generating system may be an aerosol generating article according to the present invention and as described above.

Additional features and advantages of the aerosol generating system of the present invention have been described with respect to the susceptor assembly, aerosol generating article, and heating assembly of the present invention and are therefore equally applicable.

The invention is defined in the claims. However, a non-exhaustive list of non-limiting examples is provided below. Any one or more of the features of these examples may be combined with any one or more features of another example, embodiment or aspect described herein.

Example Ex1: A current collector unit for transferring and inductively heating a liquid forming an aerosol under the influence of an alternating magnetic field, wherein the current collector unit comprises a bundle of threads, wherein the bundle of threads comprises at least a plurality of first threads including a first current collector material, wherein along at least a portion of the parallel bundle belonging to the bundle of threads, the plurality of first threads are arranged parallel to each other.

Example Ex2: A current collector assembly according to example Ex1, where the bundle of threads is a bundle of untwisted threads.

Example Ex3: A current collector assembly according to any of the previous examples, wherein the plurality of first threads are threads of a solid material.

Example Ex4: A current collector assembly according to any of the previous examples, wherein the plurality of first threads are threads of a single grade of material.

Example Ex5: A current collector assembly according to any of the previous examples, wherein the plurality of first threads are formed from a first current collector material.

Example Ex6: A current collector assembly according to any of the previous examples, wherein the first current collector material comprises or is made of one of a ferrimagnetic material or a ferromagnetic material or an electrically conductive material or an electrically conductive ferrimagnetic material or an electrically conductive ferromagnetic material.

Example Ex7: A current collector assembly according to any of the previous examples, wherein the first current collector material comprises or is made of one of ferrite, aluminum, iron, nickel, copper, bronze, cobalt, nickel alloy, unalloyed carbon steel, stainless steel, ferritic stainless steel, ferromagnetic stainless steel, martensitic stainless steel or austenitic stainless steel.

Example Ex8: A current collector assembly according to any of the previous examples, wherein the plurality of first threads have a diameter of at least 0.015 millimeters, at least 0.02 millimeters, at least 0.025 millimeters, at least 0.05 millimeters, at least 0.075 millimeters, at least 0.1 millimeters, at least 0.125 millimeters, at least 0.15 millimeters, at least 0.2 millimeters, at least 0.3 millimeters, or at least 0.4 millimeters.

Example Ex9: A current collector assembly according to any of the previous examples, wherein the plurality of first threads have a diameter of not more than 0.025 millimeters, not more than 0.05 millimeters, not more than 0.1 millimeters, not more than 0.15 millimeters, not more than 0.2 millimeters, not more than 0.25 millimeters, not more than 0.3 millimeters, not more than 0.35 millimeters, not more than 0.4 millimeters, not more than 0.45 millimeters, or not more than 0.5 millimeters.

Example Ex10: A current collector assembly according to any of the previous examples, wherein at least one of, in particular each of, the plurality of first threads has a circular, ellipsoidal, oval, triangular, rectangular, square, hexagonal or polygonal cross-section.

Example Ex11: A current collector assembly according to any of the previous examples, wherein the plurality of first threads are provided with a surface treatment, in particular including the application of a surface coating, for example an aerosol-enhancing surface coating, a liquid-attracting surface coating, a liquid-repellent surface coating, or an antibacterial surface coating.

Example Ex12: A current collector assembly according to any of the previous examples, wherein the plurality of first threads in the bundle of threads comprises 3-100 first threads, in particular 10-80 first threads, preferably 20-60 first threads, more preferably 30-50 first threads, for example 40 first threads.

Example Ex13: A current collector assembly according to any of the previous examples, wherein the bundle of threads further comprises a plurality of second threads comprising a second current collector material, wherein along at least a portion of the parallel bundle belonging to the bundle of threads, the plurality of second threads are arranged parallel to each other and to the plurality of first threads.

Example Ex14: A current collector assembly according to example Ex13, wherein the second current collector material comprises one of a ferrimagnetic material or a ferromagnetic material.

Example Ex15: A current collector assembly according to any one of examples Ex13-Ex14, wherein the second current collector material has a Curie temperature of below 500 degrees Celsius, in particular below 350 degrees Celsius, preferably below 300 degrees Celsius, more preferably below 250 degrees Celsius, even more preferably below 200 degrees Celsius, most preferably below 150 degrees Celsius.

Example Ex16: A current collector assembly according to any one of examples Ex13-Ex15, wherein the second current collector material comprises one of nickel, a nickel alloy, mu-metal or permalloy.

Example Ex17: A current collector assembly according to any of the previous examples Ex13-Ex16, wherein the plurality of second threads are threads of a solid material.

Example Ex18: A current collector assembly according to any of the previous examples Ex13-Ex17, wherein the plurality of second threads are threads of a single grade of material.

Example Ex19: A current collector assembly according to any of examples Ex13-Ex18, wherein the plurality of second threads are made of a second current collector material.

Example Ex20: A current collector assembly according to any one of examples Ex13 to Ex19, wherein the plurality of second threads provide for a surface treatment, in particular comprising applying a surface coating, for example an aerosol formation enhancing surface coating, a liquid attracting surface coating, a liquid repellent surface coating, or an antibacterial surface coating.

Example Ex21: A current collector assembly according to any of examples Ex13-Ex20, wherein at least one of, in particular each of, the plurality of second threads has a circular, ellipsoidal, oval, triangular, rectangular, square, hexagonal or polygonal cross-section.

Example Ex22: A current collector assembly according to any of the previous examples Ex13-Ex21, wherein the plurality of second threads have a diameter of at least 0.015 millimeters, at least 0.02 millimeters, at least 0.025 millimeters, at least 0.05 millimeters, at least 0.075 millimeters, at least 0.1 millimeters, at least 0.125 millimeters, at least 0.15 millimeters, at least 0.2 millimeters, at least 0.3 millimeters, or at least 0.4 millimeters.

Example Ex23: A current collector assembly according to any of the previous examples Ex13-Ex22, wherein the plurality of second threads have a diameter of not more than 0.025 millimeters, not more than 0.05 millimeters, not more than 0.1 millimeters, not more than 0.15 millimeters, not more than 0.2 millimeters, not more than 0.25 millimeters, not more than 0.3 millimeters, not more than 0.35 millimeters, not more than 0.4 millimeters, not more than 0.45 millimeters, or not more than 0.5 millimeters.

Example Ex24: A current collector assembly according to any one of examples Ex13 to Ex23, wherein the plurality of first threads and the plurality of second threads have the same diameter.

Example Ex25: A current collector assembly according to any one of examples Ex13 to Ex23, wherein the plurality of first threads and the plurality of second threads have different diameters.

Example Ex26: A current collector assembly according to any one of examples Ex13 to Ex25, wherein the plurality of second threads in the bundle of threads is from 1-100 second threads, in particular 10-80 second threads, preferably 20-60 second threads, more preferably 30-50 second threads, for example 40 second threads.

Example Ex27: A current collector assembly according to any one of examples 13-26, wherein the plurality of first threads and the plurality of second threads are substantially uniformly distributed over the bundle of threads.

Example Ex28: A current collector assembly according to any one of examples 13-26, wherein the plurality of first threads and the plurality of second threads are unevenly distributed over the bundle of threads.

Example Ex29: A current collector assembly according to any of the previous examples, wherein in the parallel bundle portion the average centre-to-centre distance between adjacent first threads and, if any, second threads is not more than 0.025 millimetres, not more than 0.05 millimetres, not more than 0.1 millimetres, not more than 0.15 millimetres, not more than 0.2 millimetres, not more than 0.25 millimetres, not more than 0.3 millimetres, not more than 0.35 millimetres, not more than 0.4 millimetres, not more than 0.45 millimetres or not more than 0.5 millimetres.

Example Ex30: A current collector assembly according to any of the previous examples, wherein the total length of the bundle of threads is in the range from 5 to 50 millimetres, in particular from 10 to 40 millimetres, preferably from 10 to 30 millimetres, more preferably from 10 to 20 millimetres.

Example Ex31: A current collector assembly according to any of the previous examples, wherein the bundle of threads comprises a branched portion at at least at one end portion of the bundle of threads, wherein a plurality of first threads and, if present, a plurality of second threads diverge from each other.

Example Ex32: A current collector assembly according to example Ex31, wherein the branched portion has a length of at least 5 percent, 10 percent, 20 percent or 30 percent of the total length of the bundle of threads.

Example Ex33: A current collector assembly according to example Ex31 or example Ex32, wherein the branched portion has a length of not more than 10 percent, 20 percent, 30 percent, 40 percent or 50 percent of the total length of the bundle of threads.

Example Ex34: A current collector assembly according to any of the previous examples, wherein the portion of the parallel bundle has a length of at least 5 percent, 10 percent, 20 percent, 30 percent, 40 percent, 50 percent, 60 percent, 70 percent or 80 percent of the total length of the bundle of threads.

Example Ex35: A current collector assembly according to any of the previous examples, wherein the portion of the parallel bundle has a length of not more than 10 percent, 20 percent, 30 percent, 40 percent, 50 percent, 60 percent, 70 percent, 80 percent, 90 percent or 100 percent of the total length of the bundle of threads.

Example Ex36: A current collector assembly according to any of the previous examples, wherein a portion of the parallel bundle is located at one end portion of the bundle of threads.

Example Ex37: A current collector assembly according to any of examples 1-36, wherein the portion of the parallel bundle is located, in particular, symmetrically between the ends of the bundle of threads.

Example Ex38: A current collector assembly according to any of the previous examples, wherein at least part of the parallel bundle is bundled using a coupling, bushing or strand.

Example Ex39: A pantograph assembly according to example Ex38, where the coupling or bushing or harness may comprise a component in the form of a shell.

Example Ex40: A current collector assembly according to any of the preceding examples, wherein the bundle of threads is a straight [non-curved, unbent] bundle of threads.

Example Ex41: A current collector assembly according to any of the previous examples, wherein at least along a portion of the parallel bundle there is a circular, ellipsoidal, oval, triangular, rectangular, square, hexagonal or polygonal cross-section.

Example Ex42: A current collector assembly according to any of the previous examples, wherein the length of the plurality of second threads differs from the length of the plurality of first threads.

Example Ex43: A current collector assembly according to any one of examples Ex1-Ex42, wherein the length of the plurality of second threads is shorter than the length of the plurality of first threads.

Example Ex44: A current collector assembly according to any one of examples Ex1-Ex42, wherein the length of the plurality of second threads is greater than the length of the plurality of first threads.

Example Ex45: An induction heating unit for transferring and inductively heating an aerosol-forming liquid, wherein the heating unit comprises:

- at least one current collector unit for transferring liquid according to any of the previous examples;

- at least one induction source, designed and placed with the possibility of generating an alternating magnetic field in the heating section of at least one unit of the current collector for transferring liquid, in particular in the heating section of the bundle of threads.

Example Ex46: A heating unit according to example Ex45, wherein the induction source comprises an induction coil arranged around the heating section of the liquid transfer current collector unit, in particular at least around the heating section of the bundle of filaments.

Example Ex47: A heating unit according to any of examples Ex45 or Ex46, wherein the heating section of the liquid transfer current collector unit, in particular the heating section of the bundle of threads, is located at one end portion of the bundle of threads.

Example Ex48: A heating unit according to any of examples Ex45-Ex47, wherein the heating section of the bundle of filaments has a length of at least 5 percent, 10 percent, 20 percent, 30 percent, 40 percent, 50 percent, 60 percent, 70 percent or 80 percent of the total length of the bundle of filaments.

Example Ex49: A heating unit according to any of examples Ex45-Ex48, wherein the heating section of the bundle of filaments has a length of no more than 10 percent, 20 percent, 30 percent, 40 percent, 50 percent, 60 percent, 70 percent, 80 percent, 90 percent or 100 percent of the total length of the bundle of filaments.

Example Ex50: A heating unit according to any of examples Ex45-Ex49, wherein the bundle of filaments is located with an offset from the center relative to the axis of symmetry of the alternating magnetic field generated by the induction source when using the heating unit.

Example Ex51: A heating unit according to any of examples Ex45-Ex50, where the heating unit further comprises a flux concentrator located around at least part of the induction coil and configured to distort the alternating magnetic field of at least one induction source towards the bundle of filaments, in particular towards the heating section of the bundle of filaments when using the heating unit.

Example Ex52: A heating unit according to example Ex51, wherein the flow concentrator comprises a flow concentrator foil, in particular a multilayer flow concentrator foil.

Example Ex53: An aerosol generating article for use with an induction heated aerosol generating device, wherein the device comprises:

- at least a first liquid reservoir for storing a first aerosol-forming liquid, wherein the first liquid reservoir comprises an outlet;

- at least a first current collector assembly for transferring liquid according to any of examples 1-44, comprising a first bundle of threads for delivering a first aerosol-forming liquid from a first liquid reservoir through an outlet in a zone outside the first liquid reservoir.

Example Ex54: An aerosol generating article according to example Ex53, wherein the first bundle of threads comprises at least one impregnation section located in the first liquid reservoir.

Example Ex55: An aerosol generating article according to example Ex54, wherein at least one impregnated section of the first bundle of threads has a length of no more than 10 percent, no more than 20 percent, no more than 30 percent, no more than 40 percent, no more than 50 percent or no more than 60 percent of the total length of the second bundle.

Example Ex56: An aerosol generating article according to example Ex54, wherein at least one impregnated section of the first bundle of threads may have a length of at least 10 percent, 20 percent, 30 percent, 40 percent, 50 percent or 60 percent of the total length of the first bundle of threads.

Example Ex57: An aerosol generating article according to any of examples Ex54-Ex56, wherein the impregnation section of the first bundle of threads is located at one end portion of the first bundle of threads.

Example Ex58: An aerosol generating article according to any of examples Ex54-Ex56, wherein the impregnation section of the first bundle of threads is located between the two ends of the first bundle of threads.

Example Ex59: An aerosol generating article according to any of examples Ex53-Ex58, wherein the first bundle of threads comprises two impregnation sites, each of which is located in the first liquid reservoir.

Example Ex60: An aerosol generating article according to any of examples Ex53-Ex59 further comprises

- at least a second liquid reservoir for storing a second aerosol-forming liquid, wherein the second liquid reservoir comprises an outlet;

- at least a second current collector assembly for transferring liquid according to any of examples 1-44, comprising a second bundle of threads for delivering a second aerosol-forming liquid from the second liquid reservoir through an outlet in a region outside the second liquid reservoir.

Example Ex61: An aerosol generating article according to example Ex60, wherein the second bundle of threads comprises at least one impregnation section located in the second liquid reservoir.

Example Ex62: An aerosol generating article according to example Ex61, wherein at least one impregnated section of the second bundle of threads has a length of no more than 10 percent, no more than 20 percent, no more than 30 percent, no more than 40 percent, no more than 50 percent or no more than 60 percent of the total length of the second bundle.

Example Ex63: An aerosol generating article according to example Ex61, wherein at least one impregnated section of the second bundle of threads has a length of at least 10 percent, at least 20 percent, at least 30 percent, at least 40 percent, at least 50 percent or at least 60 percent of the total length of the second bundle of threads.

Example Ex64: An aerosol generating article according to any of examples Ex61-Ex63, wherein the impregnation section of the second bundle of threads is located at one end portion of the second bundle of threads.

Example Ex65: An aerosol generating article according to any of examples Ex61-Ex63, wherein the impregnation section of the second bundle of threads is located between the two ends of the second bundle of threads.

Example Ex66: An aerosol generating article according to any of examples Ex60-Ex65, wherein the second bundle of threads comprises two impregnation sites, each of which is located in a second liquid reservoir.

Example Ex67: An aerosol generating article according to any of examples Ex60-Ex66, further comprising an aerosol generating liquid contained in a first liquid reservoir.

Example Ex68: An aerosol-generating article according to any of examples Ex60-Ex67, further comprising a second aerosol-generating liquid contained in a second liquid reservoir.

Example Ex69: An aerosol-generating article according to example Ex68, wherein the aerosol-generating liquid is different from the second aerosol-generating liquid.

Example Ex70: An aerosol generating system comprising an aerosol generating device with inductive heating, an aerosol generating article for use with the aerosol generating device, and an inductive heating unit according to any of examples Ex45-Ex52, wherein the inductive source of the heating unit is part of the aerosol generating device with inductive heating, and wherein the current collector unit for transferring liquid of the heating unit is part of the aerosol generating article.

Example Ex71: An aerosol generating system comprising an aerosol generating device with inductive heating and an aerosol generating article for use with the aerosol generating device, where the article comprises at least one current collector unit for transferring liquid according to any of the examples Ex1-Ex 45, and where the device comprises at least one inductive source designed and arranged to generate an alternating magnetic field in a heating section of at least one current collector unit for transferring liquid of the article, in particular in a heating section of a bundle of filaments, when the article is used with the device.

The examples will now be further described with reference to the accompanying drawings, in which:

Fig. 1 schematically shows an induction heating unit comprising a current collector unit according to a first embodiment of the present invention;

Fig. 2 shows a cross-section of the current collector unit of the heating unit according to Fig. 1;

Fig. 3 shows a current collector assembly according to a second embodiment of the present invention;

Fig. 4 shows a current collector assembly according to a third embodiment of the present invention;

Fig. 5 is a schematic representation of a first illustrative embodiment of an aerosol generating article according to the present invention, comprising a current collector assembly according to Fig. 1;

Fig. 6 schematically illustrates a second illustrative embodiment of an aerosol generating article according to the present invention, comprising two current collector assemblies according to Fig. 1; and

Fig. 7 is a schematic diagram of an illustrative embodiment of an aerosol generating system according to the present invention, which comprises an aerosol generating device and an aerosol generating article according to Fig. 5.

Fig. 1 schematically shows an induction heating unit 20 comprising a current collector unit for transporting liquid 10 according to a first embodiment of the present invention. In general, the current collector unit 10 comprises a bundle 18 of threads capable of performing two functions: transporting and heating the liquid forming an aerosol. For this purpose, the bundle 18 of threads comprises a plurality of first threads 11 and a plurality of second threads 12, wherein the plurality of first threads 11 comprise a first current collector material, and the plurality of second threads 12 comprise a second current collector material. Due to the sensitive properties of the thread materials, the first threads 11 and the second threads 12 can be inductively heated in an alternating magnetic field and, thus, can heat the liquid forming an aerosol upon thermal contact with the threads. In addition, due to the arrangement of the first and second threads 11, 12 in the bundle 18 of threads and due to the small diameter of the threads 11, 12, narrow channels are formed between the threads 11, 12, providing a capillary effect in the longitudinal direction X of the bundle 18 of threads. Thus, for example, if one end portion 13 of the bundle 18 of threads is immersed in a liquid forming an aerosol, the liquid can be transferred to the opposite end portion 14 of the bundle 18 of threads, where the transferred liquid can evaporate and be exposed to the air channel for drawing out the aerosol.

For evaporation of the liquid, the heating unit 20 further comprises an induction source 30, including an induction coil 32. In the present embodiment, the induction coil 32 is a two-layer spiral coil, each layer of which has six turns, which is capable of generating a substantially uniform alternating magnetic field. As can be seen from Fig. 1, the induction coil 32 is located around the end portion 14 of the bundle of filaments 18 in such a way as to generate an alternating magnetic field, which locally penetrates the bundle of filaments 18 only at its end portion 14. As a result, the bundle of filaments 18 is locally heated in the heating section 17 at the end portion 14. The field strength is selected such that the heating section 17 is heated to a temperature sufficient for evaporation of the liquid transferred through the bundle of filaments 18. On the contrary, due to the exclusively local heating, the remaining section of the bundle of threads 18, in particular the end section 13, maintains temperatures below the evaporation temperature. Consequently, when using the heating unit 20, the current collector unit 10 has a temperature profile along the direction X of its length with sections of higher and lower temperatures, as shown in the lower part of Fig. 1. More specifically, the temperature profile displays an increase in temperature from the end section 13 to the heating section 17 at the opposite end section 14, from temperatures below the evaporation temperature T_vap of the aerosol-forming liquid to temperatures above the corresponding evaporation temperature T_vap. Advantageously, the presence of the remaining section with a temperature below the evaporation temperature T_vap prevents the boiling of the aerosol-forming liquid in this section of the bundle of threads 18. Moreover, the use of the remaining section 16 or at least a part thereof as an impregnation section 16 for immersion in a liquid reservoir also prevents the boiling of the aerosol-forming liquid inside the reservoir.

The actual temperature profile formed when using the current collector assembly 10 depends on the thermal conductivity and the length of the bundle 18 of threads. Accordingly, in order to ensure a sufficient temperature gradient between the end portion 13 and the end portion 14, the bundle 18 requires a certain overall length. With regard to the present embodiment, the overall length of the bundle 18 of threads may be in the range from 5 to 50 millimeters, in particular from 10 to 40 millimeters, preferably from 10 to 30 millimeters, more preferably from 10 to 20 millimeters. This applies to each type of thread, that is, to the plurality of first threads 11 and to the plurality of second threads 12.

Fig. 2 shows a cross-section of the current collector unit 10 for the bundle 18 of threads along the line A-A in Fig. 1. The plurality of first threads 11 and the plurality of second threads 12 are threads of a solid material having a substantially circular cross-section. Due to the circular cross-section, the threads 11, 12 do not contact each other by area, but only by linear contact with each other, which in itself leads to the formation of capillary gaps between the plurality of threads 11, 12. Other shapes of the cross-section of the plurality of first threads 11, 12 are also permissible, for example, an oval, elliptical, triangular, rectangular, square, hexagonal or polygonal cross-section.

In order to ensure a sufficient capillary effect, the average center-to-center distance D between adjacent threads 11, 12 in a bundle of threads is no more than 0.5 millimeters, in particular no more than 0.25 millimeters, preferably no more than 0.1 millimeters, no more than 0.05 mm, even more preferably no more than 0.025 mm.

The capillary action is also facilitated by the small radius of curvature and, consequently, the small diameter of the first and second threads 11, 12. Accordingly, the plurality of second threads may have a diameter of no more than 0.025 millimeters, no more than 0.05 millimeters, no more than 0.1 millimeters, no more than 0.15 millimeters, no more than 0.2 millimeters, no more than 0.25 millimeters, no more than 0.3 millimeters, no more than 0.35 millimeters, no more than 0.4 millimeters, no more than 0.45 millimeters, or no more than 0.5 millimeters. However, the diameter of the first and second threads 11, 12 must be greater than twice the depth of the surface layer, in order to induce a sufficient amount of eddy currents and thus generate a sufficient amount of thermal energy when the bundle 18 of threads is exposed to an alternating magnetic field. Accordingly, depending on the materials and the frequency of the alternating magnetic field used, the first and second threads 11, 12 can have a diameter of at least 0.015 millimeters, at least 0.02 millimeters, at least 0.025 millimeters, at least 0.05 millimeters, at least 0.075 millimeters, at least 0.1 millimeters, at least 0.125 millimeters, at least 0.15 millimeters, at least 0.2 millimeters, at least 0.3 millimeters or at least 0.4 millimeters.

In the present embodiment, the first and second threads 11, 12 may comprise a liquid-attracting surface coating (not shown). The liquid-attracting surface coating also enhances the capillary effect of the thread bundle 18.

The first current-collecting material of the plurality of first threads 11 is optimized with respect to heat generation. For example, the first current-collecting material may be a ferromagnetic stainless steel, causing induction heating of the plurality of first threads 11 by means of eddy currents and also hysteresis losses. The Curie temperature of the ferromagnetic first current-collecting material is selected in such a way that it is significantly higher than the evaporation temperature, preferably higher than 300 degrees Celsius. In contrast, as further described above, the plurality of second threads 12 mainly serve as temperature markers. For this purpose, the second current-collecting material may be a ferromagnetic or ferrimagnetic material, which preferably has a Curie temperature of approximately at a given operating temperature of the current-collecting assembly 10. Accordingly, when the current collector assembly 10 reaches the Curie temperature of the second current collector material, the magnetic properties of the second current collector material change from ferromagnetic or ferrimagnetic to paramagnetic, which is accompanied by a temporary change in its electrical resistance. Thus, by observing a corresponding change in the electrical current consumed by the induction source 30, which is used to generate the alternating magnetic field, it is possible to determine when the second current collector material has reached its Curie temperature and, thus, when the specified operating temperature has been reached. Suitable materials for the second current collector material may be nickel, nickel alloy, mu-metal or permalloy. Only a few second threads are required for adequate operation as temperature markers. Accordingly, the number of first threads 11 may be greater, in particular, two or three times, or four times, or five times, or six times, or seven times, or eight times, or nine times, or ten times, than the number of second threads 12. In the present embodiment, the bundle 18 of threads, for example, contains forty first threads 11 and five second threads 12.

As can also be seen from Fig. 2, the plurality of second threads 12 are randomly distributed over the bundle of threads 18. The predominantly random distribution requires only minor efforts in the manufacture of the bundle of threads 18. As can also be seen from Fig. 2, the bundle of threads 18 has a substantially circular cross-section, which is particularly easy to manufacture.

Again with reference to Fig. 1, the first and second threads 11, 12 are arranged parallel to each other in such a way that they form a part 15 of a parallel bundle along the entire length of the bundle 18 of threads. That is, the bundle 18 of threads of the current collector assembly 10 is a bundle of untwisted threads, in which the first and second threads 11, 12 are not twisted or twisted and, thus, do not intersect with each other. The part 15 of the parallel bundle is particularly advantageous for ensuring a sufficient capillary effect along the entire length of the bundle 18 of threads. In addition, the current collector assembly comprising a parallel arrangement of threads is simple and economical to manufacture. In fact, the current collector assembly 10 can be made by tying into a bundle a plurality of individual threads arranged substantially parallel and cutting the bundle of threads to the desired length.

Fig. 3 shows a second embodiment of the current collector assembly 110 according to the present invention. In general, the current collector assembly of Fig. 3 is similar to the current collector assembly 10 shown in Figs. 1 and 2. Therefore, identical or similar features are designated by the same reference numerals, but with an increase of 100. In contrast to the first embodiment shown in Figs. 1 and 2, the current collector assembly 110 according to Fig. 3 comprises a branched portion 119 at the end portion 114 of the bundle of threads 118, in which the first threads 111 and the second threads 112 diverge from each other. As a consequence, the portion 115 of the parallel bundle does not extend along the entire length of the bundle of threads 118. In the present embodiment, the parallel bundle portion 150 is located at the opposite end portion 113 of the bundle of threads 118 and extends along approximately one third of the total length of the bundle of threads 118. Accordingly, the branched portion occupies approximately two thirds of the total length of the bundle of threads 118. The branched portion can reduce the impact of the evaporated aerosol-forming liquid on the air channel and, thus, reduce the formation of an aerosol. Similarly, the branched portion can be used, at least in part, as an impregnation section for immersion in the aerosol-forming liquid. To hold the threads 111, 112 together in a parallel configuration, at least in part, the parallel bundle portion 115 belonging to the bundle of threads 118 is gathered into a bundle by means of a coupling 190 or a tow. In the present embodiment, the coupling is located at the end portion 113.

In Fig. 4 a third embodiment of the current collector assembly 210 is shown, similar to the second embodiment shown in Fig. 3. Therefore, identical or similar features are again designated by the same reference numerals, but with an increase of 100. In contrast to the second embodiment shown in Fig. 3, the current collector assembly 210 according to Fig. 4 comprises two branched portions 219, one at each end portion 213, 214 of the bundle 218 of threads. Accordingly, the portion 215 of the parallel bundle is located between the two branched portions 219. In the present embodiment, the bundle 118 of threads is asymmetrical with respect to the axis of symmetry perpendicular to the length of the bundle of threads, passing through its center of mass. Each of the two branched portions 219 has a length of about 40 percent of the total length of the bundle 218 of threads, while the portion 215 of the parallel bundle has a length of about 20 percent of the total length of the bundle 218 of threads. Similar to the embodiment shown in Fig. 3, the first and second threads 211, 212 of the bundle 218 of threads according to Fig. 4 are gathered into a bundle by means of a sleeve 290 located around the portion 215 of the parallel bundle approximately in the middle of the length of the bundle 218 of threads. The configuration according to Fig. 4 can be used to implement either two heating sections or two impregnation sections at each end of the bundle. Alternatively, in this configuration, one branched portion 219 can be an impregnation section, while the other branched portion 219 can be a heating section.

Fig. 5 schematically shows a first embodiment of an aerosol-generating article 40 according to the present invention. As will be further described below with respect to Fig. 7, the aerosol-generating article 40 is configured to be used with an aerosol-generating device with induction heating. The article 40 comprises a rigid article body 43 made of a liquid-impermeable material. Together with a sleeve 44, the article body 43 forms a liquid reservoir 41 that contains an aerosol-forming liquid 51. The sleeve 44 comprises an opening that forms an outlet opening of the liquid reservoir 41. The article 40 further comprises a current collector assembly 10 for transferring liquid, corresponding to the current collector assembly 10 shown in Fig. 1. The thread bundle 18 of the current collector unit 10 passes through an opening in the sleeve 44 in such a way as to be partially located in the liquid reservoir 41 and partially in the evaporation cavity 45, which is formed by the body 43 of the article and the sleeve 44 adjacent to the liquid reservoir 41. Due to this, the thread bundle 18 is able to supply the aerosol-forming liquid 51 from the liquid reservoir 41 through the outlet opening into the area outside the liquid reservoir 41, i.e. into the evaporation cavity 45. There, the transferred liquid 51 can evaporate by means of induction heating of that part of the thread bundle 18, which is located in the evaporation cavity 45. Accordingly, that part of the thread bundle 18, which is located in the liquid reservoir 41, in particular immersed in the aerosol-forming liquid 51, acts as the impregnation section 16. The length of the impregnation section 16 can be advantageously used to control the amount of aerosol-forming liquid that is to be absorbed and transferred from the liquid reservoir 41 to the evaporation cavity 45. In the present invention, the impregnation section 16 has a length of approximately 60% of the total length of the bundle of threads 18.

Similarly, that portion of the bundle of filaments 18 which is located in the evaporation cavity 45 functions, at least in part, as a heating section 17 when it is exposed to an alternating magnetic field, as described earlier with reference to Fig. 1.

As can also be seen from Fig. 5, the article 40 comprises air inlet openings 46 in the body 43 of the article into the evaporation cavity 45, providing air supply to the evaporation cavity 45. The inlet opening 46 can be configured to provide air flow to the heating section 17 of the bundle of filaments 18 or around it. The air inlet opening 46 can be an opening in the body of the reservoir. Similarly, the air inlet opening 46 can be a nozzle configured to direct the air flow to a certain target location on the bundle of filaments 18. In addition, the article 41 comprises a mouthpiece 47, forming the near end portion of the evaporation cavity 45. The mouthpiece 47 has a tapering shape, having an air outlet opening 48 at the very end, which allows the user to directly inhale the aerosol from the article. Preferably, the mouthpiece comprises a filter (not shown). Therefore, when the user takes a puff, the aerosol-forming liquid evaporating from the heating section 17 is exposed to the air flow entering the evaporation cavity 45 through the air inlet openings 46, forming an aerosol that can be drawn out through the air outlet opening 48 in the mouthpiece 47.

In general, the aerosol generating article 40 may be a disposable aerosol generating article or a reusable aerosol generating article. In the latter case, the aerosol generating article 40 may be refillable. That is, the liquid reservoir 41 may be refilled with the aerosol generating liquid 51 after it has been exhausted.

Fig. 6 shows a second embodiment of an aerosol-generating article 340 according to the present invention. Elements similar or identical to the aerosol-generating article 40 shown in Fig. 5 are designated by identical reference numerals, but with an increase of 300. In contrast to the article 40 according to Fig. 5, the aerosol-generating article 340 according to Fig. 6 comprises two liquid reservoirs, i.e. a first liquid reservoir 341 containing a first liquid 351 forming an aerosol, and a second liquid reservoir 342 containing a second liquid 352 forming an aerosol. For each of the reservoirs 341, 342, the article 340 comprises a separate current collector unit 310, 410 for supplying the aerosol-forming liquid from the corresponding reservoir 341, 342 to the common evaporation cavity 345. Accordingly, the first current collector unit 310, containing the first bundle 318 of threads, passes from the first reservoir 341 for liquid through the corresponding opening in the sleeve 344 into the evaporation cavity 345. Similarly, the second current collector unit 410, containing the first bundle 418 of threads, passes from the second reservoir 342 for liquid through the corresponding opening in the sleeve 344 into the evaporation cavity 345.

Both current collector units 310, 410 are preferably heated simultaneously when exposed to an alternating magnetic field. Accordingly, the first and second aerosol-forming liquids evaporate simultaneously and then mix to form a composite aerosol potentially containing various substances and flavors. This is particularly applicable if the first aerosol-forming liquid and the second aerosol-forming liquid are different from each other. Therefore, the aerosol-generating article of Fig. 6 advantageously increases the variety of user sensations regarding the taste and composition of the aerosol.

Fig. 7 schematically shows an exemplary embodiment of an aerosol generating system 80 according to the present invention. The system 80 comprises an aerosol generating device 60 with inductive heating and an aerosol generating article 40 for use with the device 60. In the present embodiment, the aerosol generating article 40 corresponds to the article shown in Fig. 5. In particular, the article 40 comprises a susceptor assembly 10 for carrying and heating an aerosol-forming liquid 51 contained in the article 40. The aerosol generating device 60 is an electrically driven device capable of interacting with the article 40 to generate an aerosol by inductively heating the aerosol-forming liquid via the susceptor assembly 10. For this purpose, the aerosol generating device 60 comprises a receiving cavity 62 formed inside the housing 61 of the device in the near part of the device 60. The receiving cavity 62 is designed with the possibility of placing and removing at least a part of the aerosol generating article 40. For heating the current collector unit 10, 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 spiral coil, which is located and designed with the possibility of generating a substantially uniform alternating magnetic field. As can be seen in Fig. 1, the induction coil 32 is arranged around the near end portion of the receiving cavity 62 in such a way as to surround a portion of the bundle of threads 18 when the aerosol-generating article 40 is placed in the receiving cavity 62. In particular, the induction coil 32 is designed so that it can generate an alternating magnetic field that locally penetrates the bundle of threads 18 only in the heating section 17. In contrast, due to the local heating, the impregnation section 16 of the bundle of threads 18 maintains a temperature below the evaporation temperature. In this way, the boiling of the liquid 51 forming the aerosol in the liquid reservoir 41 is prevented.

At the same time, the induction source of the aerosol generating device 60 and the current collector unit 10 of the aerosol generating article 44 form an induction heating unit in accordance with the present invention.

The aerosol generating device 60 further comprises a controller 64 for controlling the operation of the aerosol generating system 80, in particular for controlling the heating process.

In addition, the aerosol generating device 60 comprises a power source 63 providing electrical power for generating an alternating magnetic field. Preferably, the power source 63 is a battery, such as a lithium iron phosphate battery. The power source 63 may have a capacity that allows storing sufficient energy for one or more uses by the user.

Both the controller 64 and the power source 63 are located at the distal end of the aerosol generating device 60.

For the purposes of the present specification and the appended claims, except where otherwise indicated, all numbers expressing quantities, amounts, percentages, etc., are to be understood as modified in all instances by the term "about". Furthermore, all ranges include the maximum and minimum points disclosed and include any intermediate ranges therebetween that may or may not be specifically recited herein. Therefore, in this context, the number A is to be understood as A±5 percent of A. In this context, the number A may be considered to include numerical values that are within the normal standard error of measurement of the property that the number A modifies. The number A, in some instances, when used in the appended claims, may vary by the percentages listed above, provided that the amount by which A varies does not materially affect the essential and novel characteristic(s) of the claimed invention. Furthermore, all ranges include the maximum and minimum points disclosed and include any intermediate ranges therebetween that may or may not be specifically recited herein.

Claims (34)

1. A current collector unit for transferring and inductively heating a liquid forming an aerosol under the influence of an alternating magnetic field, wherein the current collector unit comprises a bundle of threads, wherein the bundle of threads comprises at least a plurality of first threads including a first current collector material, and along at least a parallel portion of the bundle belonging to the bundle of threads, the plurality of first threads are arranged parallel to each other, wherein the bundle of threads comprises a branching portion on at least one section of the bundle of threads, in which the plurality of first threads diverge from each other. 2. The current collector assembly according to claim 1, wherein the bundle of threads further comprises a plurality of second threads comprising a second current collector material, wherein along at least a parallel portion of the bundle belonging to the bundle of threads, the plurality of second threads are arranged parallel to each other and to the plurality of first threads, wherein the second current collector material preferably comprises one of a ferrimagnetic material or a ferromagnetic material. 3. A current collector assembly according to claim 1 or 2, wherein the plurality of first threads and, if present, the plurality of second threads have a diameter of no more than 0.025 mm, no more than 0.05 mm, no more than 0.1 mm, no more than 0.15 mm, no more than 0.2 mm, no more than 0.25 mm, no more than 0.3 mm, no more than 0.35 mm, no more than 0.4 mm, no more than 0.45 mm, or no more than 0.5 mm. 4. A current collector assembly according to any one of the preceding claims, wherein the plurality of first threads and, if present, the plurality of second threads comprise a surface coating. 5. A current collector assembly according to any one of the preceding claims, wherein the plurality of first threads in the bundle of threads comprises from 3 to 100 first threads, in particular from 10 to 80 first threads, preferably from 20 to 60 first threads, more preferably from 30 to 50 first threads, such as 40 first threads, while, if present, the plurality of second threads in the bundle of threads comprises from 1 to 100 second threads, in particular from 10 to 80 second threads, preferably from 20 to 60 second threads, more preferably from 30 to 50 second threads, such as 40 second threads. 6. A current collector assembly according to any of the preceding paragraphs, wherein in the parallel portion of the bundle the average center-to-center distance between adjacent first threads and, if any, second threads is not more than 0.025 mm, not more than 0.05 mm, not more than 0.1 mm, not more than 0.15 mm, not more than 0.2 mm, not more than 0.25 mm, not more than 0.3 mm, not more than 0.35 mm, not more than 0.4 mm, not more than 0.45 mm, or not more than 0.5 mm. 7. A current collector assembly according to any of the preceding claims, wherein in the branched portion at at least one end portion of the bundle of threads, a plurality of second threads, if present, diverge from each other. 8. A current collector assembly according to any of the preceding claims, wherein the parallel portion of the bundle has a length of at least 5%, 10%, 20%, 30%, 40%, 50%, 60%, 70% or 80% of the total length of the bundle of threads. 9. A current collector assembly according to any of the preceding claims, wherein the parallel portion of the bundle is located on one end portion of the bundle of threads or the parallel portion of the bundle is located, in particular symmetrically located, between two end portions of the bundle of threads. 10. A current collector assembly according to any of the preceding claims, wherein at least part of the parallel portion of the bundle is assembled into a bundle by means of a coupling, bushing or bundle. 11. An induction heating unit for transferring and inductively heating a liquid forming an aerosol, wherein the heating unit comprises: at least one current collector assembly according to any of the preceding claims; at least one induction source, designed and placed with the possibility of generating an alternating magnetic field in the heating section of at least one unit of the current collector for transferring liquid, in particular in the heating section of the bundle of threads. 12. The heating unit according to claim 11, in which the bundle of threads is located with an offset from the center relative to the axis of symmetry of the alternating magnetic field generated by the induction source when using the heating unit. 13. An aerosol generating article for use with an induction heated aerosol generating device, the article comprising: at least a first liquid reservoir for storing a first aerosol-forming liquid, wherein the first liquid reservoir comprises an outlet; at least a first current collector assembly according to any one of claims 1-10, comprising a first bundle of threads for delivering a first aerosol-forming liquid from a first liquid reservoir through an outlet in a region outside the first liquid reservoir. 14. An aerosol generating article according to paragraph 13, additionally containing: at least a second liquid reservoir for storing a second aerosol-forming liquid, wherein the second liquid reservoir comprises an outlet; at least a second current collector assembly according to any one of claims 1 to 10, comprising a second bundle of threads for delivering a second aerosol-forming liquid from the second liquid reservoir through an opening in a region outside the second liquid reservoir. 15. An aerosol generating system comprising an aerosol generating device with induction heating and an aerosol generating article for use with the aerosol generating device, wherein the article comprises at least one current collector unit according to any one of claims 1-10, wherein the device comprises at least one induction source designed and arranged with the possibility of generating an alternating magnetic field in the heating section of at least one current collector unit for transferring liquid of the article, in particular in the heating section of a bundle of threads, when the article is used with the device. 16. A current collector unit for transferring and inductively heating a liquid forming an aerosol under the influence of an alternating magnetic field, wherein the current collector unit comprises a bundle of threads, wherein the bundle of threads comprises at least a plurality of first threads including a first current collector material, and along at least a parallel portion of the bundle of threads the plurality of first threads are arranged parallel to each other, wherein the bundle of threads additionally comprises a plurality of second threads including a second current collector material, wherein along at least a parallel portion of the bundle belonging to the bundle of threads the plurality of second threads are arranged parallel to each other and to the plurality of first threads, and the second current collector material preferably comprises one of a ferrimagnetic material or a ferromagnetic material. 17. A current collector unit for transferring and inductively heating a liquid forming an aerosol under the influence of an alternating magnetic field, wherein the current collector unit comprises a bundle of threads and the bundle of threads comprises at least a plurality of first threads including a first current collector material, and along at least a parallel portion of the bundle belonging to the bundle of threads, the plurality of first threads are arranged parallel to each other, wherein the parallel portion of the bundle belonging to the bundle of threads is arranged on one end portion of the bundle of threads or the parallel portion of the bundle belonging to the bundle of threads is arranged, in particular symmetrically arranged, between two ends of the bundle of threads. 18. An induction heating unit for transferring and inductively heating a liquid forming an aerosol, wherein the heating unit comprises: at least one current collector assembly for transferring liquid, intended for transferring and inductively heating a liquid forming an aerosol under the influence of an alternating magnetic field, wherein the current collector assembly comprises a bundle of threads, wherein the bundle of threads comprises at least a plurality of first threads including a first current collector material, and along at least a parallel portion of the bundle belonging to the bundle of threads, the plurality of first threads are arranged parallel to each other; at least one induction source, configured with the possibility and installed for generating an alternating magnetic field in the heating section of at least one unit of the current collector for transferring liquid, in particular in the heating section of the bundle of threads, in this case, the bundle of threads is not located in the center relative to the axis of symmetry of the alternating magnetic field generated by the induction source when using a heating unit. 19. An aerosol generating article for use with an induction heated aerosol generating device, the article comprising: at least a first liquid reservoir for storing a first aerosol-forming liquid, wherein the first liquid reservoir comprises an outlet; at least a first current collector assembly for transporting and inductively heating the aerosol-forming liquid under the influence of an alternating magnetic field, wherein the current collector assembly comprises a first bundle of threads for delivering the first aerosol-forming liquid from the first liquid reservoir through the outlet opening to a region outside the first liquid reservoir, wherein the first bundle of threads comprises at least a plurality of first threads including a first current collector material, and along at least a parallel portion of the bundle of the first bundle of threads the plurality of first threads are arranged parallel to each other, wherein the aerosol generating product additionally contains: at least a second liquid reservoir for storing a second aerosol-forming liquid, wherein the second liquid reservoir comprises an outlet; at least a second current collector assembly for transferring liquid, intended for transferring and inductively heating the aerosol-forming liquid under the influence of an alternating magnetic field, wherein the current collector assembly comprises a second bundle of threads for delivering the second aerosol-forming liquid from the second liquid reservoir through the outlet opening to a region outside the second liquid reservoir, wherein the second bundle of threads comprises at least a plurality of first threads including the first current collector material, and along at least a parallel portion of the bundle of the second bundle of threads the plurality of first threads are arranged parallel to each other. 20. A current collector assembly for transmitting and inductively heating a liquid forming an aerosol under the influence of an alternating magnetic field, wherein the current collector assembly comprises a bundle of threads, wherein the bundle of threads comprises at least a plurality of first threads, including a first current collector material, and along at least a parallel portion of the bundle belonging to the bundle of threads, the plurality of first threads are arranged parallel to each other, wherein the plurality of first threads comprise a surface coating.