Aerosol generating device and method for indicating the operating state of an aerosol generating device - Patents.com

Abstract

The aerosol generating device (10) has a thermochromic material visible from outside the device (10) and extending in a longitudinal direction, and a heat transfer structure internal to the device (10) relative to the thermochromic material and extending essentially in the same longitudinal direction as the thermochromic material and at least overlapping the thermochromic material, the thermal resistance of the heat transfer structure increasing in the longitudinal direction. Further, a method is presented for indicating at least one operating state of the aerosol generating device by changing the color of the thermochromic material visible from outside, where at least two portions of the thermochromic material are heated sequentially due to the thermal resistance of the heat transfer structure internal to the device relative to the thermochromic material increasing in the longitudinal direction of the thermochromic material and the heat transfer structure.

Description

[Technical field]

[0001] The present invention relates to an aerosol generating device and a method for indicating the operating state of an aerosol generating device. [Background technology]

[0002] In recent years, traditional smoking products have been increasingly replaced by aerosol generating devices in which liquid is vaporized and can be inhaled by a user. In this regard, it is desirable to indicate to a user at least one operational state of the aerosol generating device that is related to its readiness for inhalation by the user, such as a heating state.

[0003] US Patent No. 10849360B2 relates to an aerosol generating device having an LED array, where the LEDs are switched corresponding to a heater also provided in the array and / or controlled by a controller. In addition, a temperature-indicating paint corresponding to the heater can be provided. Similar devices can be derived from Korean Patent Application Publication No. 20200000635A and Chinese Utility Model No. 210747275U. Summary of the Invention [Problem to be solved by the invention]

[0004] Nonetheless, there remains a need to provide the described information to a user while maintaining a simple structure of the device without complicating the control logic. [Means for solving the problem]

[0005] This is achieved by the subject matter of claims 1 and 13.

[0006] Thus, the aerosol generating device has a thermochromic material visible from the outside of the device and extending in a longitudinal direction, which may also typically be the longitudinal direction of the device, in other words the direction corresponding to the longest side of the device. Furthermore, the heat transfer structure is provided inside the device relative to the thermochromic material and extends essentially in the same longitudinal direction as the thermochromic material and at least overlaps the thermochromic material. Finally, the thermal resistance of the heat transfer structure, which preferably comprises the heat transfer material, increases in a gradual or stepwise manner in the longitudinal direction, but in any case does not necessarily follow a monotonic curve.

[0007] This structure has the effect that the longitudinally extending thermochromic material changes its color gradually or stepwise. Specifically, a first portion, part or section of the thermochromic material may change its color first, thus indicating to a user that, for example, heating has begun. As heating continues and the temperature of heating increases, thereby transferring more heat to the thermochromic material despite the partial increase in thermal resistance, due to the gradual increase in thermal resistance, further portions, sections or parts of the thermochromic material will gradually change their color. The portions that are successively heated and thus change color may essentially have the shape of a bar or column, but may also resemble a trademark, brand or logo.

[0008] The described structure is relatively robust, inexpensive and ergonomic, and may even entertain the user waiting for the heating to be completed, due to the fact that the user can actually watch and observe the continuous heating process, which corresponds to the continuous color change of the thermochromic material. In this regard, the thermochromic material may originally have a color that essentially corresponds to the color of the outside of the device, so that the indicators described herein are initially invisible or nearly invisible. Furthermore, the thermochromic material may advantageously be selected to change to a color significantly different from the color of the outside of the device when heated, so that the continuous heating is easily visible. Furthermore, a progressive color change has the advantage that it is easier for the user to judge the progress of the heating, compared to a simple static color change in the same permanent part of the device provided with the thermochromic material. Furthermore, the device may be simplified, both in terms of internal structure and control logic.

[0009] Advantageous embodiments are described in the further claims.

[0010] If, as is presently preferred, the thermal resistance is highest at the mouthpiece end of the device, this has the advantage that the progressive colour change moves towards the mouthpiece, thereby giving the user an easy to understand perception of progressive heating until the mouthpiece in the direction of the colour change becomes usable for inhalation.

[0011] Thermochromic materials, particularly paints, can be smoothly and visually attractively incorporated into the device when filled into at least one recess formed on the surface of the device, in this way the material is easily visible while at the same time avoiding or at least minimizing disruptions on the device surface.

[0012] With regard to the specific type of thermochromic material, leuco dye-based paints are currently preferred.

[0013] Regarding the details of the heat transfer structure, which serves to transfer heat from a heater such as an oven to the thermochromic material, it is preferably adapted to reduce the temperature present at the inner end of the heat transfer structure by at least about 75%, preferably at most about 90%. This is related to the fact that the outer surface of the device, which needs to transfer heat, must not be too hot, because there would be a risk of a too high temperature being applied to the user's hand. Typically, considering a target temperature of the oven of about 250°C, the temperature at the outer end of the heat transfer structure, in other words its end or surface that is essentially in contact with the thermochromic material and transfers heat to the thermochromic material, must be at most about 45°C.

[0014] Because heat can be transferred to some extent longitudinally of the heater structure, the heater structure can be kept longitudinally shorter than ovens or other heaters internal to the device, thus simplifying the structure and still providing sufficient heat transfer.

[0015] This can be particularly well ensured if the heat transfer structure completely overlaps the heating device in the longitudinal direction.

[0016] The internal structure can be particularly simplified if heat is transferred directly to the heat transfer structure by a heating device, but the heat transfer structure can alternatively or additionally be adapted to be heated by electrical resistance, which can for example be easily controlled based on the progress of the heating.

[0017] As already indicated above, this will be particularly easy and particularly visible if a thermochromic material is provided on at least one part of the device surface.

[0018] With regard to the thermal resistance of the heat transfer structure increasing in its longitudinal direction, this can be easily achieved by constructing the heat transfer structure from at least two different materials, the contents of which vary along the longitudinal direction. The different materials typically have different thermal resistances, and by varying their contents along the longitudinal direction, the thermal resistance can be appropriately varied, in particular increased or decreased depending on the direction considered.

[0019] Such a combination of two different materials can be realized particularly easily if at least one step is provided in the different materials, so that when the different materials are combined in a complementary manner, the dimension measured along the step remains the same throughout the heat transfer structure, but there is a different content of the different materials along the longitudinal direction.

[0020] The same effect is essentially achieved if different materials are provided with at least two protrusions having different thicknesses measured in the longitudinal direction, and these protrusions are interdigitated with each other, so that the thermal resistance along the longitudinal direction can also be appropriately adjusted.

[0021] In the method of indicating at least one operating state of the aerosol generating device described herein, at least two portions of the thermochromic material are heated sequentially due to the structure detailed above. Further details and preferred embodiments of the method described herein essentially correspond to those of the device and therefore may also be applied to the method, and vice versa, taking into account any method features mentioned herein.

[0022] The invention will now be described with reference to exemplary embodiments thereof. [Brief description of the drawings]

[0023] [Figure 1] A series of schematic diagrams of an aerosol generating device having an indicator as described herein are shown. [Diagram 2]2 shows the internal structure of the main part of the device in the first embodiment. [Diagram 3] 1 shows the internal structure of the main part of the device in the second embodiment. [Figure 4] 1 shows an alternative embodiment of a heat transfer structure. [Diagram 5] A detail of FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] As can be seen from Fig. 1, the aerosol generating device 10 can essentially have a rectangular appearance with its longest side and thus its longitudinal direction running vertically in Fig. 1. At the top of the device 10 the tobacco stick 12 can be seen, so that the top end according to Fig. 1 essentially corresponds to the mouthpiece end. As can be seen from Fig. 1A, in the illustrated embodiment, the thermochromic material is essentially invisible, since before heating begins it has essentially the same color as the outside of the device 10.

[0025] However, as can be seen in Figure 1B, in the illustrated embodiment, as heating begins, a circle or large dot 14 appears, which in the illustrated embodiment is located just above the horizontal center and the longitudinal center, indicating that heating has begun. As can be seen in Figures 1C-1E, the color change progresses essentially towards the end of the mouthpiece as the dot 14 grows and forms a sort of column 16 as can be seen in Figure 1E. As soon as the column stops growing towards the end of the mouthpiece, heating is complete, indicating to the user that the first puff can be taken.

[0026] Figure 2 shows some details of the internal structure of the device 10. This detail is only relevant insofar as there is a tubular oven 18 into which the tobacco stick 12 is essentially inserted, and the heat transfer structure 20 abuts the oven along a substantial length thereof. In the embodiment shown, the length of the heat transfer structure 20 is less than the length of the oven, and essentially all of the heat transfer structure 20 abuts the oven 18. On the outside of the heat transfer structure 20 is provided a thermochromic material 22, which is successively visible as dots 14 in Figure 1B and finally as columns 16 in Figure 1E. In the embodiment of Figure 2, the heat transfer structure is provided towards one of the smaller sides of the device 10.

[0027] In contrast, in the embodiment of Figure 3, the heat transfer structure 20 is provided towards one of the larger sides that faces the viewer in Figure 1. This can be seen from the fact that one of the smaller sides would face the viewer in Figure 3 if the side had not been removed to show the internal structure, whereas the dimensions of Figure 2 show that one of the larger sides would face the viewer in Figure 2.

[0028] As shown in more detail in Fig. 5, it has already been shown in Fig. 3 that two different materials with different diagonal lines form the heat transfer structure, each of which is provided with three steps 24 in the illustrated embodiment. Furthermore, the two different materials are combined with each other in a complementary manner such that the dimensions measured from left to right in Fig. 3, Fig. 4 and Fig. 5 remain the same along the longitudinal direction, which is vertical in all figures. However, due to the fact that most of the materials present at the bottom of Fig. 5 have a smaller thermal resistance than most of the materials present towards the top of Fig. 5, the thermal resistance is smaller at the bottom and increases progressively towards the top. As a result, the color change progresses as shown in Fig. 1.

[0029] This also applies to the alternative embodiment shown in FIG. 4, in which both materials that together constitute the heat transfer structure have a number of protrusions 26, the width of which varies along the longitudinal direction. In particular, the width measured in the longitudinal direction of the material with the lower thermal resistance is greater at the bottom of FIG. 4 and smaller at the top of FIG. 4, which is exactly the opposite for the other material with the higher thermal resistance, whereby the total thermal resistance increases towards the top of FIG. 4. In particular, the two materials are interlocking, in other words, each protrusion is housed in the space between two protrusions of the other material, thereby achieving an essentially solid heat transfer structure with the desired thermal resistance gradient, as in the case of the embodiments of FIG. 3 and FIG. 5. This results in the same progression or vertical movement of the color change shown in FIG. 1. In other words, due to the increase in thermal resistance towards the top of the drawing, the color changes towards the top, achieving the desired visual effect.

Claims

1. An aerosol generating device (10), comprising: a thermochromic material (22) visible from the outside of the device (10) and extending in the longitudinal direction; a heat transfer structure (20) inside the device (10) with respect to the thermochromic material (22), essentially extending in the same longitudinal direction as the thermochromic material (22) and at least overlapping the thermochromic material (22); The aerosol generating device (10) having a thermal resistance of the heat transfer structure (20) increasing in the longitudinal direction.

2. The aerosol generating device (10) according to claim 1, wherein the thermal resistance is highest at the mouthpiece end of the device (10).

3. The aerosol generating device (10) according to claim 1 or 2, wherein the thermochromic material (22) is filled in at least one recess formed on the surface of the device.

4. The aerosol generating device (10) according to claim 1 or 2, wherein the thermochromic material (22) is a leuco dye-based paint.

5. The aerosol generating device (10) according to claim 1 or 2, wherein the heat transfer structure (20) inside the device (10) with respect to the thermochromic material (22) is adapted to reduce the temperature by at least about 75%, preferably up to about 90%.

6. The aerosol generating device (10) according to claim 1 or 2, wherein the heat transfer structure (20) inside the device (10) with respect to the thermochromic material (22) is shorter than the oven (18) in the longitudinal direction of the device (10).

7. The aerosol generating device (10) according to claim 6, wherein the heat transfer structure (20) completely overlaps the oven (18) in the longitudinal direction.

8. The aerosol generating device (10) according to claim 1 or 2, wherein the heat transfer structure (20) inside the device (10) with respect to the thermochromic material (22) is adapted to be heated by electrical resistance.

9. The aerosol generating device (10) according to claim 1 or 2, wherein the thermochromic material (22) is provided on at least one part of the surface of the device (10).

10. The aerosol generating device (10) according to claim 1 or 2, wherein the heat transfer structure (20) is composed of at least two different materials, the content of which varies along the longitudinal direction.

11. The aerosol generating device (10) according to claim 10, wherein the different materials are provided with at least one step (24).

12. The aerosol generating device (10) according to claim 10, wherein the different materials are provided with at least two protrusions (26) having different thicknesses measured in the longitudinal direction.

13. A method of indicating at least one operating state of an aerosol generating device by changing the color of a thermochromic material visible from the outside of the device, wherein at least two portions of the thermochromic material are sequentially heated due to an increase in the thermal resistance of a heat transfer structure inside the device with respect to the thermochromic material in the longitudinal direction of the thermochromic material and the heat transfer structure.

14. The method according to claim 13, wherein heat is transferred to the thermochromic material from an oven and / or an electrical resistance.

15. The method according to claim 14, wherein the oven and / or the electrical resistance is controlled by a controller.

Images