WO2022069226A1

WO2022069226A1 - Assembly for generating aerosol

Info

Publication number: WO2022069226A1
Application number: PCT/EP2021/075326
Authority: WO
Inventors: Patrick Scheunemann
Original assignee: Hauni Maschinenbau Gmbh
Priority date: 2020-09-30
Filing date: 2021-09-15
Publication date: 2022-04-07
Also published as: CN116234457A; DE102020125538A1; US20230363462A1; EP4221522A1

Abstract

The invention relates to an assembly for generating aerosol, comprising an evaporator chamber, a mouthpiece with an outlet for aerosol, and a mixing chamber with an air inlet. The evaporator chamber is equipped with an electric heating element for evaporating a liquid, said heating element being in contact with a wick material which is designed to supply the liquid to be evaporated to the electric heating element. The evaporator chamber comprises at least one first nozzle which is arranged in the wall of the evaporator chamber such that a fluidic connection is formed by the nozzle between the evaporator chamber and the mixing chamber so that the liquid evaporated in the evaporator chamber can enter the mixing chamber as a free jet of steam. The assembly is designed such that the free jet of steam is mixed with an air flow entering via the air inlet in the mixing chamber in order to generate an aerosol, and the generated aerosol can exit the assembly via the outlet of the mouthpiece.

Description

Arrangement for aerosol generation

description

The invention relates to an arrangement for aerosol generation, a cartridge for an evaporator system comprising a corresponding arrangement, an evaporator system comprising such a cartridge and a method for aerosol generation. k

The subject matter of the invention is defined in the appended claims.

It is known that the administration of active ingredients via the respiratory tract is an efficient and gentle method of supplying the human or animal body with physiologically active substances, with particular focus on classic inhalation methods, which can be carried out with some of the simplest means, both in conventional medicine and under have found a permanent place in home remedies. In these simple processes, an active substance dissolved in a carrier substance, often water, is usually heated in a pot or similar vessel and thereby evaporated.

Due to the increasingly critical assessment of smoking in many parts of the world, i.e. the consumption of tobacco products by burning them and inhaling the resulting smoke, for example in the form of cigarettes or cigars, such inhalation methods have increasingly become the focus of interest in recent years , in which the physiologically active substances that are traditionally absorbed through tobacco smoke are instead applied via corresponding inhalation methods that do not burn tobacco, whereby this concept is also transferred to other active substances that are otherwise often associated with smoking, such as such as tetrahydrocannabinol (THC) and other cannabinoids.

The progressive technical development has made it possible to design corresponding evaporator systems for evaporating an active ingredient-containing composition ever smaller, so that today evaporator systems are available with which the evaporation of an active ingredient-containing composition can be carried out in a portable hand-held device which, for example, is the size of a traditional cigar or a Cigarette box may have. The most prominent applications for corresponding vaporizer systems are electronic cigarettes and inhalers for medical applications.

The systems known today are mostly based on the fact that a composition stored in a reservoir, which is regularly referred to as a liquid, is vaporized by a more or less controlled supply of thermal energy from a heating element, e.g. a heating wire coil, so that the user inhales the resulting vapors can. The liquid is often fed from the reservoir to the heating element through a wick, so that the term wick-spiral systems is often used. A corresponding system is disclosed, for example, in US 20140096782 A1.

The vaporized liquid forms an aerosol in the confluence with air in the vaporizer system, which contains fine droplets that are formed by condensation from the gas phase. Parts of the evaporated liquid usually remain in the gaseous state, although in many commercially available systems it is also possible that larger droplets are also contained in the aerosol, which are thrown out of the liquid phase during boiling.

A major challenge with evaporator systems intended to replace conventional cigarettes is to provide the user with a smoking experience comparable to that of conventional cigarette products, so that the user has a smoking experience comparable to that of a conventional cigarette when using the evaporator system. When using corresponding evaporator systems in the medical field, on the other hand, the focus is on the application of the active substance contained being able to take place precisely in a designated area of the respiratory tract. In both cases, these specifications must ideally be consistently implementable over a large number of uses.

In extensive series of tests, the inventors examined these aspects, ie the optimal smoking experience and the targeted application of medicinal active ingredients in the respiratory tract. According to the inventors' knowledge, both effects are probably decisively determined by the size of the droplets generated in the aerosol and in particular their droplet size distribution. For example, droplets with a diameter of approx. 1 to 5 μm are preferred in the lower respiratory tract deposited, whereas droplets larger than 8 pm largely remain in the upper airways. Very fine droplets, on the other hand, are partially exhaled by the user.

According to the inventors, the depth of penetration of the generated droplets into the respiratory tract is relevant to the question of whether a smoking experience similar to that of a classic smoking product can be achieved with an evaporator system. The inventors have recognized in the course of their own investigations that it is important to provide evaporator systems that enable an optimal consumption experience or medical inhalers that enable optimal application of the active ingredients contained, to achieve a consistent and reproducible aerosol quality that is possible should ideally be characterized by a specifically adjustable droplet size distribution. In this respect, it was found that conventional evaporator systems known from the prior art, in particular wick-coil systems, regularly do not meet these requirements.

The primary object of the present invention was to specify an arrangement for aerosol generation which eliminates or at least reduces the disadvantages of the prior art.

It was a particular object of the present invention to specify an arrangement for aerosol generation which can generate an aerosol of particularly high quality. It was a requirement that the arrangement for aerosol generation should be able to generate the aerosol with the most consistent quality possible, even over numerous uses.

In addition, it was an object of the present invention that the arrangement for aerosol generation can generate an aerosol whose mean droplet size can be set in a targeted manner and whose droplet size distribution is as narrow as possible. It was an additional task that the arrangement for aerosol generation should be able to provide an aerosol that has a particularly small average droplet size in order to enable the aerosol to penetrate deeply into the respiratory tract. An additional object of the invention was also to specify an arrangement for aerosol generation in which the unintentional entrainment of larger, unevaporated droplets from the liquid to be evaporated is reliably prevented.

Ideally, the tasks specified above should be achievable with comparatively minor modifications to conventional evaporator systems. In addition, the arrangement for aerosol generation should advantageously be at least as powerful as the evaporator systems known from the prior art in terms of the amount of aerosol generated, i.e. the aerosol yield that can be achieved from the mouthpiece for each milliliter of liquid evaporated.

The inventors have recognized that the objects described above can be achieved by controlled guidance of the fluid flows occurring inside the evaporator system. In the arrangements known from the prior art, the air flow required for aerosol generation is usually guided directly over the surface of the heated and evaporated liquid, for example by flowing directly around a wick-spiral structure. In this case, there is not only the danger that larger, non-evaporated droplets of the liquid are unintentionally entrained, but according to the inventors' knowledge, there can be locally strongly fluctuating mixing ratios between vapor and air over the surface of the boiling liquid, which leads to controlled aerosol formation, in particular one controlled aerosol formation with a narrow droplet size distribution. In the case of these structures, the possibility of specifically influencing the droplet size or the droplet size distribution is regularly small, especially since the fluid flows inside these evaporator systems can vary greatly due to the different suction behavior of the users.

Surprisingly, it has now been found that the controlled fluid flow required to solve the above-mentioned tasks can be realized if the vapor generated by an electric heating element from a liquid to be evaporated does not enter a mixing chamber in an uncontrolled manner, in which mixing with an air flow takes place, but an arrangement for aerosol gene tion is provided in which the steam produced is controlled, ie as a steam free jet, is guided into the mixing chamber. This is achieved by providing an evaporator chamber from which the free jet of vapor can escape through a nozzle arranged in the wall of the evaporator chamber, through which the vapor is driven due to its own vapor pressure in the evaporator chamber. This arrangement makes it possible to achieve a controlled and as uniform as possible mixing of air and vapor in the mixing chamber, with which a high level of stability and reproducibility of the aerosol properties is achieved.

With a corresponding arrangement, the aerosol formation in the mixing chamber can take place at the greatest possible distance from the wall areas, which reduces the loss of aerosol due to unwanted condensation. With a corresponding arrangement for aerosol generation, it is also possible to achieve particularly small average droplet sizes and, particularly advantageously, narrow droplet size distributions.

Without wishing to be bound by this theory, the inventors assume that the number of initial droplets formed by homogeneous nucleation, which can serve as nuclei for further condensation, depends on the rate of change of the air mass break over time when a critical air mass break is reached in depends on the current. The critical air mass fraction depends on the vaporized substance and the temperatures of the fluids mixed with one another.

It is probably the case that - at least in the size range that is practically relevant - the greatest possible rate of change that a small volume moving with the flow experiences when the critical situation is reached leads to a larger number of droplets being formed, whereby it cannot be ruled out that that an extremely high rate of change can lead to crossing the critical region too quickly, which could have an adverse effect on the bacterial count. This large number of droplets formed by homogeneous nucleation leads to a small mean droplet size and a narrow droplet size distribution. Thus, the inventors have recognized that the fastest possible mixing of air and steam must be realized when a low average droplet size and a narrow droplet size distribution are the goal.

In the course of development, the inventors have succeeded in realizing precisely these above-described conditions of controlled and rapid mixing of the fluids for generating a large rate of change over time in the air mass fraction by using a steam free jet. It has proven to be particularly advantageous here that the use of a steam free jet can reduce local fluctuations in the steam concentration compared to the prior art, which disadvantageously increase the distribution width of the particle sizes in the evaporator systems known from the prior art.

By using a steam free jet, especially in the area of the laminar flow of the steam free jet, particularly controlled and constant conditions can be achieved in which the mixing of steam and air depends mainly on the diffusion speed of the stratified flows, which is The design of an evaporator system is particularly easy to control. In addition, compared to the prior art, particularly high-frequency and small-scale turbulence occurs in the turbulent area of the steam free jet, which also enables particularly fast and low-fluctuation mixing with the surrounding air and thus efficient aerosol generation.

In the light of this, a person skilled in the art will recognize that the above objects are achieved by assemblies, cartridges, evaporator systems and methods as defined in the claims. Preferred configurations according to the invention result from the dependent claims and the following statements.

Such features of cartridges, evaporator systems and methods according to the invention, which are referred to below as preferred, are combined in particularly preferred embodiments with other features referred to as preferred. Combinations of two or more of the items designated below as particularly preferred are therefore very particularly preferred. Preferred features of corresponding cartridges, evaporator systems and methods according to the invention result from the features of preferred arrangements according to the invention.

The invention relates to an arrangement for generating aerosols, comprising an evaporator chamber, a mouthpiece with an outlet for aerosol and a mixing chamber with an air inlet, with an electrical heating element for evaporating a liquid being arranged in the evaporator chamber, which is provided with a wicking material, i.e. a porous material with capillary action, which is set up to supply the electric heating element with the liquid to be evaporated, wherein the evaporator chamber comprises at least one first nozzle which is arranged in the wall of the evaporator chamber in such a way that a fluid-conducting connection between the evaporator chamber and the Mixing chamber is formed, so that the vaporized liquid in the evaporator chamber can enter the mixing chamber as a vapor free jet, the arrangement being designed such that the vapor free jet in the mixing chamber to generate an aerosol with an air entering via the air inlet ftstrom be mixed and the aerosol generated can exit the assembly via the outlet of the mouthpiece.

The arrangement according to the invention comprises an evaporator chamber, a mouthpiece with an outlet for an aerosol and a mixing chamber with an air inlet. In the context of the present invention, the evaporator chamber and the mixing chamber are to be understood as chambers that are at least partially separated from one another by design measures. In contrast to the prior art, in which the evaporator chamber is usually also the chamber in which the vapor generated is mixed with the supplied air, the arrangement according to the invention thus comprises at least two separate chambers which are at least partially separated from one another by design measures, so that a fluid cannot pass completely unhindered from the evaporator chamber into the mixing chamber. In this case, such arrangements according to the invention are particularly preferred in which an in the evaporator chamber generated steam can enter the mixing chamber essentially exclusively via the first nozzle.

According to the invention, the mixing chamber has an air inlet. In the simplest embodiment, this air inlet can be a simple recess in the wall of the mixing chamber. The purpose of the air inlet is that when the arrangement according to the invention is used, i.e. a user sucks on the mouthpiece, air can enter the mixing chamber from outside the arrangement, in order not only to allow pressure equalization, but also the air required for aerosol generation provide as air flow. Arrangements according to the invention are preferred, with an air filter for filtering the air flow entering the mixing chamber being arranged at the air inlet or in a supply line to the air inlet, or with the air inlet being connected to a supplementary tank for receiving clean air, with the supplementary tank preferably being a pressure vessel is.

In the arrangement according to the invention, the evaporator chamber comprises an electrical heating element. This electrical heating element serves to vaporize a liquid which can be supplied via a wicking material which is in contact with the electrical heating element. The electrical heating element makes it possible to convert a liquid to be evaporated into the gas phase within the evaporator chamber and thus to generate a vapor.

According to the invention, the evaporator chamber comprises at least one first nozzle through which the vapor generated can enter the mixing chamber. In the context of the present invention, the term nozzle, in agreement with the expert understanding, denotes a technical device for influencing a fluid flow when passing from the evaporator chamber into the mixing chamber, through which the pressure of the vapor produced in the evaporator chamber by evaporation of the liquid is converted into kinetic energy of the steam is transformed. The nozzle can, for example, have a constant cross section, be tapered or have more complex shapes. From a functional point of view, the nozzle must be able to convert the steam pressure built up inside the evaporator chamber into kinetic energy of the steam so that it enters the mixing chamber as a steam free jet. In the context of the present invention, a free jet is a flow from a nozzle into a free space that is not limited by walls, so that the steam flowing out of the nozzle and the gas in the mixing chamber have different speeds, with the gas surrounding the free jet being regularly sucked in by it and will be carried away.

In the simplest arrangement according to the invention, the evaporator chamber comprises only a first nozzle. However, a particular advantage of the arrangement according to the invention is that the flow properties of the free steam jet can also be adapted by providing more than one first nozzle, from which the steam can enter the mixing chamber as a free steam jet. This is also particularly advantageous because, for example, by selecting nozzles of different sizes and shapes, complex distributions of particle sizes can also be achieved in a targeted manner, in that the particle sizes achieved with each individual steam free jet are superimposed. This makes it possible, for example, to apply two different active ingredients simultaneously to different areas of the respiratory tract.

The arrangement according to the invention is designed in such a way that the free jet of steam emerging from the evaporator chamber through the nozzle is mixed in the mixing chamber with an air flow entering via the air inlet, so that the temperature of the resulting mixture in the mixing chamber is reduced and a very high level of supersaturation occurs. which leads to homogeneous condensation, i.e. to homogeneous nucleation, with the desired high nucleation rate.

The at least one first nozzle can either be provided as a separate component that is fastened in the wall of the evaporator chamber, or in simple configurations can also be formed directly by the wall of the evaporator chamber, so that its design forms a nozzle as an outlet opening into the mixing chamber . For reasons of cost, preference is given to an arrangement according to the invention, the at least one first nozzle being formed by the wall of the evaporator chamber. Our own tests and associated simulations have shown that the best results are achieved with arrangements according to the invention in which the heating element and the first nozzle are arranged on different sides of the evaporator chamber, in particular on opposite sides. According to the knowledge of the inventors, this makes it possible to generate a pressure build-up that is as uniform as possible in the interior of the vaporizer chamber and thus a vapor free jet that is as uniform as possible, with which the best results can often be achieved when generating aerosols.

Particularly in those cases in which flat electrical heating elements are used, for example flat heater chips or heatable wire meshes, the electrical heating element can also be integrated into the wall of the evaporator chamber. This means that the evaporator chamber is delimited at least in sections by the electrical heating element. An arrangement according to the invention is therefore preferred, in which the electric heating element is arranged in the evaporator chamber in such a way that the electric heating element forms part of the evaporator chamber, preferably part of the wall of the evaporator chamber.

Even if this is not preferred in many cases, it is also possible in the light of the above statements that the electric heating element not only forms part of the wall of the evaporator chamber, but at the same time also forms the first nozzle or one of the first nozzles or all first nozzles are formed. For example, a flat heater chip can be designed with continuous recesses that function as nozzles through which the steam generated below the heater chip in the contact area of the wick can enter the mixing chamber as a steam free jet. Arrangements according to the invention are therefore preferred, in which the at least one first nozzle is formed by a component separate from the electric heating element or by the heating element arranged in the wall of the evaporator chamber, with the at least one first nozzle very particularly preferably being formed by a component separate from the electric heating element is formed.

In the course of the development of the invention, it was initially assumed that in order to solve the tasks defined above, the arrangement according to the invention would necessarily have to be designed in such a way that the air flows tion enters the mixing chamber as a free jet of air. In the course of further development of the invention, however, it has been shown that this is not necessary and that the essential feature for solving the tasks described above is the arrangement according to the invention with the corresponding first nozzle and the corresponding design of the steam flow as a steam free jet. Nevertheless, it has been shown that an arrangement according to the invention, in which the air flow also enters the mixing chamber as a free jet of air, can offer advantages for certain applications in particular, in particular since the controllability of aerosol formation is further increased and the person skilled in the art has an additional setting option for fine adjustment of the gets aerosol formation. These tests have shown that the desirable high mixing rates can be achieved in particular with second nozzles that are designed as nozzles that taper towards the mixing chamber, with the flow profile generated by a flat nozzle having proven to be particularly efficient.

Accordingly, an arrangement according to the invention is preferred, wherein the air inlet comprises at least one second nozzle, so that the incoming air flow can enter the mixing chamber as a free jet of air, wherein the at least one second nozzle is preferably a nozzle that tapers towards the interior of the mixing chamber and/or or wherein the at least one second nozzle is preferably a flat nozzle, preferably a flat rectangular nozzle, wherein the combined cross-sectional area of all second nozzles is preferably in the range of 0.5 to 10 mm ² , preferably 1 to 4 mm ² .

When the inventive arrangement disclosed above is used using a first and a second nozzle, it has been found advantageous to orient the components of the inventive arrangement such that the steam free jet and the air free jet intersect in the mixing chamber. It was found here that with regard to the angle of intersection between the central rays of the two free rays, a large spectrum of angles is possible, as a result of which a particularly high degree of design freedom is advantageously obtained. However, it has been shown that particularly good aerosol qualities with the narrowest possible droplet size distribution in particular be achieved if the angle between the free jets is selected so that they meet as orthogonally as possible.

Accordingly, a preferred arrangement according to the invention is preferred, with the air inlet and the evaporator chamber being arranged in such a way that the free steam jet and the free air jet intersect in the mixing chamber, preferably in the area of the laminar flow, so that the central jets of the free steam jet and the Air free jet enclose an angle in the range of 5 ° to 175 °, preferably 30 ° to 150 °, particularly preferably 50 ° to 130 °, very particularly preferably 70 ° to 110 °, wherein the angle is preferably essentially 90 °.

As an alternative to the arrangement described above, which uses a direct mixing of the two directed free jets, such arrangements according to the invention have proven to be particularly advantageous for certain applications in which the aerosol formation takes place above all in the border area between the steam free jet and the incoming air flow , i.e. in which the aerosol formation is mainly due to the diffusion at the boundary layer, which advantageously also enables an additional control of the aerosol formation process via the temperature of the fluids used. A preferred arrangement according to the invention is therefore preferred, with the air inlet and the evaporator chamber being arranged in such a way that the steam free jet and the incoming air flow in the mixing chamber run essentially parallel to one another, at least in sections.

For this purpose, the free steam jet or the first nozzle of the evaporator chamber and the air inlet must either be arranged directly in such a way that the air flow and the free steam jet run parallel to one another at least in sections inside the mixing chamber, or one or more air guiding elements must be provided in the mixing chamber be, so that at least partially parallel guidance is made possible. Of course, it has proven to be expedient here to provide appropriate air guiding elements for the air flow and not for the free steam jet, especially since a deflection of the free steam jet would also lead to unwanted condensation on the air guiding elements. Therefore, an arrangement according to the invention is preferred, wherein the air inlet and the at least one first nozzle of the evaporator chamber are arranged in such a way that the free steam jet and the incoming air flow in the mixing chamber run parallel to one another at least in sections, or one or more air guiding elements are arranged in the mixing chamber in such a way that the steam free jet and the incoming air flow in the mixing chamber at least partially parallel to each other. In accordance with the expert understanding, the term parallel in the context of the present invention means that the fluid flows are essentially parallel, with an angle included by the flows of 5° or less, preferably 2° or less, particularly preferably 1° or less. can be considered essentially parallel.

For the preferred arrangement described above, in which the fluid flows run parallel to one another at least in sections, two constructive arrangements have proven particularly useful. In the first variant, air inlets are provided on different, opposite sides of the first nozzle, so that the airflow entering through them flanks and flows around the steam free jet on at least two sides, in order to create a particularly large contact area in which the aerosol generation in the border area is below comparable conditions. In terms of reproducibility and the particle size distribution obtained, this has proven to be more advantageous than if the air flow only enters the mixing chamber from one side and first has to flow around the free steam jet in order to also prevent aerosol formation on the side of the free steam jet facing away from the air inlet condition. In this case, there are different condensation conditions on the different sides of the free steam jet, which inherently also lead to different average droplet sizes and broader droplet size distributions.

An arrangement according to the invention has proven to be an alternative embodiment to the approach described above, in which a single air inlet is formed around the first nozzle or the first nozzles, so that, for example, an annular air inlet extends coaxially around the first nozzle. The corresponding arrangement creates conditions that are as uniform as possible on all sides of the free steam jet and has proven to be one of the ments in which the area of the parallel laminar flows between the incoming air flow and the steam free jet in the mixing chamber is so constant over particularly long distances that the aerosol generation is advantageously particularly strongly influenced by the diffusion processes at the boundary layer. Accordingly, an arrangement according to the invention is preferred, in which the mixing chamber has at least two air inlets or one individual air inlet surrounding the at least one first nozzle, which are arranged in such a way that the air flow entering the mixing chamber is at least partially on two sides of the steam free jet runs parallel to the steam free jet.

As already disclosed above for the second nozzle, it has proven to be advantageous to design the at least one first nozzle or all first nozzles as nozzles that taper towards the mixing chamber. Such nozzles, which are also referred to as confusers, are particularly well suited to increasing the speed of the vapor emerging from the evaporator chamber and to obtaining a vapor free jet that is as favorable as possible for the invention. An embodiment in which the first nozzle is a flat nozzle has also proven to be particularly advantageous for the first nozzle. With the same volume flow, such a flat nozzle generates a steam free jet with a particularly large surface area, as a result of which a large border area to the surrounding air flow is obtained, in which the aerosol formation can take place particularly efficiently through condensation. According to the inventors, particularly extensively condensed aerosols, i.e. dense aerosols, are obtained with corresponding flat nozzles, in which the average droplet size is particularly low due to the high number of initial germs. The combination that both the first and the second nozzle are designed as flat nozzles has proven to be particularly preferred, since the free jets obtained with a flat profile in the case of intersecting free jets have a comparatively small and well-defined crossing area in terms of volume have, whereby a particularly controlled aerosol formation is possible.

Accordingly, an arrangement according to the invention is preferred, wherein the at least one first nozzle is a nozzle that tapers towards the mixing chamber, and/or wherein the combined cross-sectional area of all the first nozzles is im Range from 0.01 to 1 mm ² , preferably in the range from 0.05 to 0.8 mm ² , particularly preferably in the range from 0.1 to 0.5 mm ² , very particularly preferably in the range from 0.15 to 0 4 mm ² , and/or wherein the at least one first nozzle is a flat nozzle, preferably a flat nozzle with a rectangular cross section, preferably with a gap width of 0.3 mm or less, preferably 0.2 mm or less, particularly preferably 0.05mm or less.

The inventors have recognized that, in order to achieve the most advantageous possible generation of aerosols, it makes sense to provide the largest possible thermal gradient between the fluids involved. This means that the temperature difference between the hot steam free jet and the incoming cold air flow should be as large as possible. In this respect, the inventors have observed that, in particular during continued operation of an arrangement according to the invention, for example in an electronic cigarette, the operation of the electric evaporator unit can lead to the entire arrangement heating up, which also heats the air flow entering the mixing chamber before aerosol generation. thereby reducing the temperature gradient. It has been found to be advantageous that this problem can be eliminated or at least reduced in a synergistic manner with the arrangement according to the invention. Since the evaporator chamber in the arrangement according to the invention is already separated from the mixing chamber or other components of the arrangement for the purpose of generating the steam free jet, it is possible to make the evaporator chamber or the walls of the evaporator chamber entirely or partially from a thermally insulating material form, which at least partially shields the remaining components of the arrangement according to the invention from the thermal energy generated by the electric heating unit. This ensures that a temperature gradient that is as high and as constant as possible can be maintained between the emerging free jet of steam and the air flow. An arrangement according to the invention is preferred, in which the evaporation chamber has walls which are formed at least in sections from a thermally insulating material or are coated with a thermally insulating material, the thermally insulating material preferably having a thermal conductivity of 0.5 W/(m K) or less, preferably 0.1 W/(m K) or less. For this purpose, the person skilled in the art can choose from a wide range of thermally insulating materials, the person skilled in the art having to find a suitable compromise between low thermal conductivity and good workability of the material that meets his needs, the latter being particularly dependent on the rest of the structure envisaged by the person skilled in the art arrangement depends. In addition to a large number of possible plastics, typical insulating materials such as mineral wool or aerogels, which are usually characterized by the porous structure frequently encountered for corresponding insulating materials, have proven themselves as insulating material.

The inventors have also recognized that under certain circumstances it can be particularly advantageous to form the first nozzle or all first nozzles at least partially from a thermally conductive material or to coat them with a thermally conductive material. Only at first glance does this contradict the advantages disclosed above of designing the evaporator chamber from insulating material. In addition to unwanted heating of the air flow by the electrical heating element, which should be prevented by the thermally insulating material, there can be another problem in the evaporator chamber.

Since the vapor exits from the vaporization chamber essentially via the first nozzle or the first nozzles in arrangements according to the invention, the inner walls of the vaporization chamber represent condensation surfaces on which unwanted condensation of the vapor can occur. In the case of this unwanted condensation, part of the vapor, which should actually emerge as a vapor free jet into the mixing chamber in order to contribute to the formation of aerosols there, condenses as condensed liquid on the walls of the evaporator chamber, from where the liquid, in the worst case, even as large , unevaporated drops can reach the user via the mouthpiece. This process reduces the vapor concentration and corresponding losses occur, which reduces the efficiency of aerosol generation and the aerosol yield. Naturally, this effect occurs not only on the walls, but also on the first nozzle, especially since the steam has to be guided through a comparatively small volume at this point, which in many cases is also covered by the Rear side is cooled by the incoming air flow and can easily become a condensing surface for the vapor due to the corresponding lower temperatures. This goes as far as theoretical configurations in which the part of the vapor condensing in the first nozzle could lead to a reduction in the effective cross section of the first nozzle during continued operation and thus change the aerosol generation behavior of the entire arrangement according to the invention.

To solve this problem, it is expedient, as indicated above, to make the first nozzle and/or the inner sides of the evaporator chamber from a thermally conductive material, with typical metals such as copper, aluminum and platinum or semimetals such as silicon having proven particularly suitable. In very particularly preferred embodiments of the arrangement according to the invention, the correspondingly designed inner sides of the evaporator chamber and/or the first nozzle can be thermally coupled to the heating element and/or to a separate heating device in order to ensure during operation of the arrangement according to the invention that these components are on such a high temperature that condensation of the steam on these components can be prevented or at least reduced. In our own tests, the first embodiment has proven to be particularly advantageous, i.e. if the corresponding components are used with the electric heating element that is already present and already available for generating the steam, since in this case the basic function of the electric heating element is used in a synergistic manner can, in order to compensate for this partially occurring peculiarity of the arrangement according to the invention.

In the light of the above statements, arrangements according to the invention are preferred, in which the evaporation chamber has walls which are formed at least in sections on the inside of the evaporation chamber from a thermally conductive material or are coated with a thermally conductive material, the thermally conductive material having a thermal conductivity of 20 W / (m K) or more, preferably 80 W / (m K) or more, and wherein the thermally conductive material on the inside of the evaporator chamber thermally coupled to the electrical heating element and / or with a separate heating device, and/or wherein the first nozzle is formed from a thermally conductive material having a thermal conductivity of 20 W/(m K) or more, preferably 80 W/(m K) or more, and wherein the first nozzle is preferably is thermally coupled to the electric heating element and/or connected to a separate heating device.

Arrangements according to the invention are particularly preferred in which the individual components are aligned with one another in such a way that the aerosol formation takes place inside the mixing chamber, i.e. at the greatest possible distance from the inner walls of the mixing chamber. From a flow dynamic point of view, it has proven to be particularly advantageous if the mixing chamber tapers towards the mouthpiece, so that the aerosol outlet in the mouthpiece in turn functions as a kind of nozzle that increases the kinetic energy of the aerosol produced in the direction of the user. An arrangement according to the invention is therefore preferred in which the mixing chamber has a non-uniform cross-sectional profile along the flow direction of the aerosol, with the cross-section of the mixing chamber preferably decreasing in the direction of the mouthpiece.

Even if it is fundamentally possible to operate the arrangement according to the invention with all possible forms of electrical heating elements, for example with wick-coil arrangements, the inventors' tests have clearly shown that the use of a plate-shaped heating chip is particularly advantageous. Such a plate-shaped heater chip allows a particularly good and controlled generation of steam and thus supports the general aim of the arrangement according to the invention to carry out the generation of steam and aerosol as controlled as possible. In addition, a corresponding plate-shaped heater chip can be thermally coupled particularly well to other components of the evaporator chamber and, due to its shape, can also be provided particularly easily as a component of the evaporator chamber. In this case, the heater chip is particularly preferably arranged on the bottom of the evaporator chamber, ie on a side opposite the first nozzle. A corresponding plate-shaped heater chip can also be designed in such a way that it not only forms part of the wall of the evaporator chamber, but also forms the first nozzle or several first nozzles in its interior, which are present in the inventive arrangements. see are. An arrangement according to the invention is therefore preferred in which the electrical heating element is a wire coil or a plate-shaped heater chip, preferably a plate-shaped heater chip, particularly preferably a plate-shaped heater chip made of a doped or undoped semiconductor material, which preferably has a large number of microchannels running through it.

The arrangement according to the invention can be combined with a liquid reservoir for receiving the liquid to be evaporated, as a result of which a so-called cartridge is obtained which is suitable for use in evaporator systems, for example in electronic cigarettes. Corresponding cartridges are often designed as disposable parts that form an evaporator system together with a reusable part.

The invention thus also relates to a cartridge for an evaporator system comprising an arrangement according to the invention and a liquid reservoir for receiving the liquid to be evaporated.

A cartridge according to the invention is preferred, wherein the liquid reservoir comprises one or more materials selected from the group consisting of glass, crystal, metal, ceramics, wood and plastic, wherein the reservoir preferably has another outer shell and/or wherein the liquid reservoir is preferred is equipped with an element for pressure equalization.

A cartridge according to the invention is also preferred, the liquid reservoir being formed by a bag, the bag being made entirely or partially of silicone, rubber, latex or another suitable elastic or non-elastic material, preferably a plastic. The use of bags as a liquid reservoir is particularly advantageous, since these are inexpensive to manufacture and regularly produce only small amounts of waste. In addition, it is advantageously not necessary to provide pressure equalization in the liquid reservoir, since the bag will contract if necessary if the internal pressure remains the same. In addition, bags are advantageous for certain applications from a safety point of view because they do not splinter and are therefore associated with less potential for danger. Preference is given to cartridges according to the invention, comprising a liquid in the liquid reservoir, the liquid comprising at least one active substance component, at least one first carrier substance with a higher boiling point than the active substance component and at least one second carrier substance with a lower boiling point than the active substance component, with the active substance component preferably being selected from the group consisting of from nicotine, tetrahydrocannabinol, cannabidiol, substances from the corresponding substance classes and medicinal active ingredients, and the liquid preferably also comprises one or more solvents selected from the group consisting of 1,2-propanediol, glycerol and water.

The liquid specified above has proven to be particularly advantageous in practice in order to provide an active substance component to a user by means of an arrangement according to the invention via a corresponding aerosol. In the context of the invention, it was recognized that particularly small droplet sizes and a particularly narrow droplet size distribution can be achieved in particular when the highest possible glycerol content is used. Correspondingly, cartridges according to the invention are preferred, comprising a liquid in the liquid reservoir, the proportion by mass of glycerol based on the total mass of the liquid being in the range of 20-80%, preferably 30 to 60%.

As explained above, in arrangements according to the invention, the steam free jet and the air flow supplied for aerosol generation can be adjusted in a targeted manner in order to obtain the desired aerosol properties. In practice, this can result in the fluid volume of non-condensed vapour, air and aerosol exiting the mixing chamber being insufficient to quickly equalize the pressure differential built up in the user's mouth by the user's suction, especially if a second nozzle is also used is used, which limits the volume of airflow entering the mixing chamber. In this case, despite the excellent aerosol quality, the user's vapor experience may be adversely affected by the perception that the inventive arrangement offers too much resistance to the user's sucking. In this case, it has proven advantageous to use one or more air chambers in cartridges according to the invention. provide channels with which additional air can be guided past the mixing chamber to the user in order to compensate for the circumstance described above. Thus, a cartridge according to the invention is preferred, comprising one or more air ducts which are designed to guide air past the mixing chamber to the mouthpiece. It has proven to be particularly expedient if valves are provided in the additional air ducts, which only open when a predetermined pressure difference is exceeded, so that at least at the beginning of a puff the pressure difference generated by the user essentially causes the free steam jet and the Air flow are formed inside the mixing chamber.

The invention also relates to an evaporator system for evaporating a liquid, preferably for use in a portable evaporator, preferably in a hand-held device, particularly preferably in an e-cigarette or an inhaler for medical purposes, comprising a cartridge according to the invention and a reusable element comprising at least one electric Energy source for the operation of the electrical heating element, preferably a battery or a fuel cell, particularly preferably a lithium ion battery, in particular a lithium polymer accumulator, the cartridge and the reusable element being reversibly and non-destructively detachably connected or connectable to one another, so that electrical contact between the electrical Energy source and the electric heating element is formed. The use for medical purposes includes in particular the application of medication for respiratory diseases and painkillers.

Finally, the invention also relates to a method for aerosol generation, preferably carried out with an arrangement according to the invention, comprising the steps: a) evaporating a liquid in an evaporator chamber, with an electrical heating element arranged in the evaporator chamber, b) discharging the evaporated liquid from the evaporator chamber into a Mixing chamber through at least one first nozzle arranged in the wall of the evaporator chamber for generating a steam free jet, c) generating an aerosol in the mixing chamber by mixing the free steam jet with an air flow entering the mixing chamber via an air inlet, and d) discharging the generated aerosol from the mixing chamber via the outlet of a mouthpiece.

The method according to the invention is preferably carried out using an arrangement according to the invention or a preferred arrangement according to the invention. The method according to the invention provides that a liquid is evaporated by means of an electrical heating element in an evaporator chamber. The steam generated is then discharged from the evaporator chamber into a mixing chamber, with the discharge taking place through a first nozzle arranged in the wall of the evaporator chamber, so that a free jet of steam is obtained. An aerosol is then generated in the mixing chamber by mixing the free steam jet with an air flow entering the mixing chamber via an air inlet. This aerosol generated in this way is finally fed from the mixing chamber to the user via the outlet of a mouthpiece.

Preferred embodiments of the invention are explained and described in more detail below with reference to the accompanying drawings. show:

1 shows a schematic representation of a preferred cartridge according to the invention with an arrangement according to the invention in cross section;

2 shows a schematic section of a preferred arrangement according to the invention in cross section;

3 shows a schematic section from a preferred arrangement according to the invention;

4a shows a schematic section of a preferred arrangement according to the invention in cross section; 4b shows a schematic section from a preferred arrangement according to the invention in a plan view;

5 shows a schematic representation of a flat nozzle;

Fig. 6a is a schematic representation of a first relative arrangement of first and second nozzles;

Fig. 6b is a schematic representation of a second relative arrangement of first and second nozzles;

Fig. 6c is a schematic representation of a third relative arrangement of first and second nozzles;

1 shows a schematic cross-sectional illustration of a cartridge 42 according to the invention, which comprises an arrangement 10 according to the invention. In the evaporator chamber 12, an electrical heating element 24 is arranged, which is designed as a plate-shaped heater chip. This electrical heating element 24 is in contact with a wicking material 28 by means of which the liquid 26 to be evaporated is fed from the liquid reservoir 44 to the electrical heating element 24 . In the example shown in Figure 1, the wicking material 28 is a non-woven fabric. The liquid reservoir 44 is made of glass, with the liquid comprising a mixture consisting of 1,2-propandyol, glycerin and water as the solvent, in which nicotine is dissolved as the active ingredient component. The arrangement shown in FIG. 1 is designed for a liquid evaporation rate of 2 mg/s, which requires a heating power of about 3-4 W. The mixing rate of air to vapor ranges from 5:1 to 10:1, so the mass air flow is about 10 to 16 mg/s and the volumetric air flow is about 8 to 16 cm ³ /s.

A first nozzle 30a is arranged in the evaporator chamber 12 or in the wall 32 of the evaporator chamber 12 and forms a fluid-conducting connection between the evaporator chamber 12 and the mixing chamber 20 . The first nozzle 30a ensures that the vaporized liquid 26 enters the mixing chamber 20 as a vapor free jet 34, the first nozzle 30a in the embodiment shown being designed as a first nozzle 30a with a round cross section that tapers in the direction of the mixing chamber. In the mixing chamber 20 the steam free jet 34 is mixed with an air flow 36 entering via the air inlet 22a, so that an aerosol 18 is generated which can exit from the arrangement 10 via the mouthpiece 14 or the corresponding outlet 16 of the mouthpiece 14 . In FIG. 1, the electric heating element 24 is arranged in the evaporator chamber 12 in such a way that it is opposite the first nozzle 30a, which is not designed as a separate component but is formed by the wall 32 of the evaporator chamber 12.

Also in the preferred embodiment illustrated in Figure 1, the air inlet 22a includes a second nozzle 38a which is configured as a tapered nozzle of circular cross-section. The air inlet 22a and the evaporator chamber 12 or the air inlet 22a and the first nozzle 30a are arranged relative to one another in such a way that the steam free jet 34 and the air free jet 40 meet at an angle in the mixing chamber 20 in the region of the laminar flow. which is essentially 90°.

In order to prevent unwanted heating of the incoming air flow 36 by the electric heating element 24, the walls 32 of the evaporator chamber 12 are made of plastic in the embodiment shown, which assumes the function of thermal insulation. The mixing chamber 20 has a non-uniform cross-sectional profile along the direction of flow of the aerosol 18 , with the mixing chamber 20 tapering particularly in the direction of the mouthpiece 14 . A corresponding cartridge 42, as shown schematically in FIG. 1, can be combined with a reusable part, in which an electrical energy store for operating the electrical heating element 24 is arranged, reversibly and non-destructively detachably to form an evaporator system according to the invention.

2 schematically shows a section of a preferred arrangement 10 according to the invention in cross section, in which the generation of the aerosol 18 takes place in particular in the border area of the steam free jet 34 to the incoming air flow 36 . In order to generate the aerosol 18 as uniformly as possible, two separate air inlets 22a, 22b are provided on opposite sides of the first nozzle 30a, which in turn is formed by the walls 32 of the evaporator chamber 12, so that the resulting air flow 36 generates the vapor free jet 34 surrounded as evenly as possible on both sides. In the preferred embodiment shown in FIG. 2, the electrical heating element 24 is again designed as a plate-shaped heater chip, which is traversed by a large number of microchannels 25, through which the liquid 26 provided by the wicking material 28 and evaporated by the electrical heating element 24 flows through the electrical Heating element 24 can pass through.

FIG. 3 visualizes schematically that the first nozzle 30a and second nozzle 38a shown in FIG. 1 can be displaced relative to one another, so that the steam free jet 34 and the air free jet 40 enclose an angle that is less than 90°.

4a and 4b each show in cross section and in top view an alternative embodiment to the preferred arrangement according to the invention shown in FIG. In the cross-sectional view in Fig. 4a it can be seen that the vapor generated in the vaporization chamber 12 enters the mixing chamber 20 as a vapor free jet 34 and is enclosed on all sides by the air flow 36, so that the aerosol 18, in particular at the boundary layer between the vapor -Free jet 34 and the air flow 36 is formed while it is guided through the mixing chamber 20 to the outlet 16 for the aerosol 18 arranged in the mouthpiece 14 .

The difference from the embodiment shown in FIG. 2 can be seen in the fact that in this case only one air inlet 22a is provided, which, however, is arranged around the first nozzle 30a in such a way that a coaxial structure results and the air inlet 22a incoming air flow 36 surrounds the steam free jet 34 on all sides, as visualized in FIG. 4b.

FIG. 5 schematically shows a flat nozzle with a rectangular cross section, which has proven to be a particularly suitable nozzle shape within the scope of the invention, in particular when it is designed as a nozzle that tapers in the direction of the mixing chamber 20, as shown in FIG. The flat nozzle shown schematically in FIG. 5 has proven to be an advantageous embodiment both for the first nozzle 30a and for the second nozzle 38a, since free jets with a particularly large surface area or lateral surfaces are thus obtained. 6a, 6b and 6c possible configurations of nozzles are shown schematically, which can be provided in an arrangement as shown in Fig. 1, ie an arrangement 10 according to the invention, in which both a steam free jet 34 and an air free jet 40 are used, which intersect in the mixing chamber 20. FIG. 6a shows a single first nozzle 30a and a single second nozzle 38a, which each taper in the direction of the mixing chamber and have a round cross section, as is also disclosed in FIG.

In contrast to this, both the air inlet 22a and the outlet 16 from the evaporator chamber 12 in FIG. 6b are designed in such a way that four nozzles are used in each case. Thus there are four first nozzles 30a, 30b, 30c, 30d and a total of four second nozzles 38a, 38b, 38c, 38d. In the example shown in FIG. 6b, the individual nozzles are each designed as nozzles with a constant and round cross section.

In contrast to this, FIG. 6c shows an embodiment in which both the first nozzle 30a and the second nozzle 38a are designed as flat nozzles with a rectangular cross section Nozzles with a cross-sectional profile that is constant over the entire length can be used.

reference sign

10 arrangement

12 vaporizer chamber

14 mouthpiece

16 outlet

18 aerosol

20 mixing chamber

22a, 22b air inlet

24 electric heating element

25 micro channels

26 liquid

28 wicking material

30a, 30b, 30c, 30d first nozzle

32 wall

34 steam jet

36 air flow

38a, 38b, 38c, 38d second nozzle

40 air free jet

42 cartridge

44 fluid reservoir

Claims

Claims Arrangement (10) for aerosol generation, comprising an evaporator chamber (12), a mouthpiece (14) with an outlet (16) for an aerosol (18) and a mixing chamber (20) with an air inlet (22a, 22b), wherein in the Evaporator chamber (12) an electrical heating element (24) for evaporating a liquid (26) is arranged, which is in contact with a wicking material (28) which is set up to supply the electrical heating element (24) with the liquid (26) to be evaporated , wherein the evaporator chamber (12) comprises at least one first nozzle (30a, 30b, 30c, 30d) which is arranged in the wall (32) of the evaporator chamber (12) in such a way that a fluid-conducting connection between the evaporator chamber (12) and and the mixing chamber (20), so that the liquid (26) evaporated in the evaporator chamber (12) can enter the mixing chamber (20) as a vapor free jet (34), the arrangement (10) being designed such that the steam free jet (34) in the mixing chamber (20) for generating the aerosol (18) with an air flow (36) entering via the air inlet (22a, 22b) and the generated aerosol (18) via the outlet (16) of the mouthpiece (14) from the arrangement ( 10) can escape. Arrangement (10) according to claim 1, wherein the air inlet (22a, 22b) comprises at least one second nozzle (38a, 38b, 38c, 38d), so that the incoming air flow (36) as an air free jet (40) in the mixing chamber ( 20), wherein the at least one second nozzle (38a, 38b, 38c, 38d) is preferably a nozzle that tapers towards the interior of the mixing chamber and/or wherein the at least one second nozzle (38a, 38b, 38c, 38d) is preferably is a flat nozzle, preferably a flat nozzle with a rectangular cross-section, the combined cross-sectional area of all second nozzles (38a, 38b, 38c, 38d) preferably being in the range of 0.5 to 2 mm ² , preferably 0.8 to 1.4 mm ² , located.

28 Arrangement (10) according to claim 2, wherein the air inlet (22a, 22b) and the evaporation chamber (12) are arranged such that the steam free jet (34) and the air free jet (40) cross in the mixing chamber (20). , preferably in the area of laminar flow, so that the central jets of the steam free jet (34) and the air free jet (40) form an angle in the range from 5° to 175°, preferably 30° to 150°, particularly preferably 50° to 130° °, very particularly preferably 70° to 110°, the angle preferably being essentially 90°. Arrangement (10) according to claim 1 or 2, wherein the air inlet (22a, 22b) and the evaporator chamber (12) are arranged such that the vapor free jet (34) and the incoming air flow (36) in the mixing chamber (20) at least sections run substantially parallel to each other. Arrangement (10) according to claim 4, wherein the air inlet (22a, 22b) and the at least one first nozzle (30a, 30b, 30c, 30d) of the evaporator chamber (12) are arranged so that the vapor free jet (34) and the The incoming air flow (36) in the mixing chamber (20) run parallel to one another at least in sections, or one or more air guiding elements are arranged in the mixing chamber (20) in such a way that the steam free jet (34) and the incoming air flow (36) in the Mixing chamber (20) at least partially parallel to each other. Arrangement (10) according to one of claims 4 or 5, wherein the mixing chamber (20) has at least two air inlets (22a, 22b) or a single air inlet (22a, 22b) surrounding the at least one first nozzle, which are arranged or is that the incoming air flow (36) in the mixing chamber (20) at least in sections two sides of the free steam jet (34) runs parallel to the free steam jet (34). Arrangement (10) according to any one of claims 1 to 6, wherein the at least one first nozzle (30a, 30b, 30c, 30d) is a nozzle tapering towards the mixing chamber (20), and/or wherein the combined cross-sectional area of all first nozzles ( 30a, 30b, 30c, 30d) in the range from 0.01 to 1 mm ² , preferably in the range from 0.05 to 0.8 mm ² , particularly preferably in the range from 0.1 to 0.5 mm ² , very particularly preferably in the range from 0.15 to 0.4 mm ² , and/or wherein the at least one first nozzle (30a, 30b, 30c, 30d) is a flat nozzle, preferably a flat nozzle with a rectangular cross section, preferably with a gap width of 0.3 mm or less, preferably 0.2 mm or less, particularly preferably 0.05 mm or less. Arrangement (10) according to any one of claims 1 to 7, wherein the evaporator chamber (12) has walls (32) which are formed at least in sections from a thermally insulating material or are coated with a thermally insulating material, the thermally insulating material preferably being a thermal conductivity of 0.5 W/(mK) or less, preferably 0.1 W/(mK) or less. Arrangement (10) according to one of Claims 1 to 8, the evaporation chamber (12) having walls (32) which are formed at least in sections on the inside of the evaporation chamber (12) from a thermally conductive material or are coated with a thermally conductive material , wherein the thermally conductive material has a thermal conductivity of 20 W / (m K) or more, preferably 80 W / (m K) or more, and wherein the thermally conductive material on the inside of the ver- steam chamber (12) is thermally coupled to the electrical heating element (24) and/or connected to a separate heating device, and/or wherein the at least one first nozzle (30a, 30b, 30c, 30d) is made of a thermally conductive material with a thermal conductivity of 20 W/(m K) or more, preferably 80 W/(m K) or more, and wherein the at least one first nozzle (30a, 30b, 30c, 30d) is preferably thermally coupled to the electric heating element (24) and /or connected to a separate heater. Arrangement (10) according to one of claims 1 to 9, wherein the electrical heating element (24) is a wire coil or a plate-shaped heater chip, preferably a plate-shaped heater chip, particularly preferably a plate-shaped heater chip made of a doped or undoped semiconductor material, which is preferably from a plurality of Microchannels (25) is traversed. Cartridge (42) for an evaporator system comprising an arrangement (10) according to one of Claims 1 to 10 and a liquid reservoir (44) for receiving the liquid (26) to be evaporated. A cartridge (42) according to claim 11, comprising one or more air ducts which are adapted to lead air past the mixing chamber (20) to the mouthpiece (14). Evaporator system for evaporating a liquid (26), preferably for use in a portable evaporator device, preferably in a hand-held device, particularly preferably in an e-cigarette or an inhaler for medical purposes, comprising a cartridge (42) according to one of Claims 11 or 12 and a reusable element comprising at least one electrical energy source for operating the electrical heating element (24), the cartridge (42) and the reusable element being reversibly and non-destructively detachably connected or connectable to one another, so that an electrical contact is formed between the electrical energy source and the electrical heating element (24). will. Method for generating aerosols, preferably carried out with an arrangement (10) according to one of Claims 1 to 10, comprising the steps: a) evaporating a liquid (26) in an evaporator chamber (12) with an electrical heating element arranged in the evaporator chamber (12). (24), b) the evaporated liquid (26) is discharged from the evaporation chamber (12) into a mixing chamber (20) through at least one first nozzle (30a, 30b, 30c, 30d) arranged in the wall (32) of the evaporation chamber (12). ) for generating a free steam jet (34), c) generating an aerosol (18) in the mixing chamber (20) by mixing the free steam jet (34) with an air inlet (22a, 22b) into the mixing chamber (20) incoming air flow (36), and d) discharging the generated aerosol (18) from the mixing chamber (20) via the outlet (16) of a mouthpiece (14).

32