INFRARED HEATED AEROSOL-GENERATING ELEMENT

Abstract

An aerosol-generating element for generating an aerosol in a shisha device, the aerosol-generating element comprising a receptacle for receiving an aerosol-forming substrate and a photonic device configured to generate a beam of IR radiation, wherein the aerosol-generating element is arranged to heat the aerosol-forming substrate by directing the beam of IR radiation onto the aerosol-forming substrate. The invention is further directed to a shisha device comprising the aerosol-generating element, an aerosol-generating system comprising both the shisha device and an aerosol-generating article, and a method for forming an aerosol in a shisha device.

Claims

1. An aerosol-generating element for generating an aerosol in a shisha device, the aerosol-generating element comprising: a receptacle for receiving an aerosol-forming substrate; and a photonic device configured to generate a beam of IR radiation; wherein the aerosol-generating element is arranged to heat the aerosol-forming substrate by directing the beam of IR radiation onto the aerosol-forming substrate.

2. An aerosol-generating element according to claim 1, wherein a wavelength of the beam of IR radiation corresponds to a wavelength at which at least a component of the aerosol-forming substrate absorbs IR radiation.

3. An aerosol-generating element according to claim 1, wherein a range of wavelengths of the beam of IR radiation is from 800 nanometers to 2300 nanometers.

4. An aerosol-generating element according to claim 1, wherein a diameter of the beam of IR radiation is in the range of from 1 millimeter to 110 millimeters.

5. An aerosol-generating element according to claim 1, wherein the power of the beam of IR radiation is in the range of from 0.1 Watt to 30 Watts.

6. An aerosol-generating element according to claim 1, wherein the energy density of the beam of IR radiation may be in a range of from 0.010 Watt per square centimeter to 30 Watts per square centimeter.

7. An aerosol-generating element according to claim 1, wherein the photonic device comprises an IR laser diode.

8. An aerosol-generating element according to claim 1, further comprising an optical element being located between the photonic device and the receptacle and being configured to manipulate the beam of IR radiation.

9. An aerosol-generating element according to claim 8, wherein the optical element is arranged on a movable optical mount for dynamically manipulating the beam of IR radiation.

10. An aerosol-generating element according to claim 8, further comprising a window being located between the photonic device and the receptacle and being substantially transparent for the beam of IR radiation.

11. An aerosol-generating element according to claim 10, wherein the aerosol-generating element comprises an optical element and, wherein the window is located at a position in between the optical element and the receptacle.

12. An aerosol-generating element according to claim 1, wherein the beam of IR radiation comprises an incident beam of IR radiation propagating from the photonic device towards the optical element and a reflected beam of IR radiation propagating from the optical element to the receptacle, and wherein there is an angle between the incident beam of IR radiation and the reflected beam of IR radiation, preferably, wherein the angle is about 90 degrees, wherein the optical element comprises a curved mirror for reflecting the beam of IR radiation, wherein the curved mirror can be manipulated dynamically.

13. An aerosol-generating element according to claim 8, wherein the optical element comprises one or both of: a concave lens for diverging the beam of IR radiation in a direction towards the receptacle; and a convex lens for converging the beam of IR radiation in a direction towards the receptacle.

14. An aerosol-generating element according to claim 1, further comprising an electrical heating means arranged for heating the aerosol-forming substrate received in the receptacle, preferably, the electrical heating means being one or more of a resistive heating means and an inductive heating means.

15. An aerosol-generating element according to claim 1, further comprising a control unit for a user to select a specific portion of the receptacle to be heated.

16. A shisha device comprising the aerosol-generating element of claim 1.

17. An aerosol-generating system comprising the shisha device of claim 16 and an aerosol-forming substrate, wherein the aerosol-forming substrate is arranged to be received in the receptacle of the aerosol-generating element of the shisha device, and wherein the aerosol-forming substrate is arranged to be heated by the aerosol-generating element of the shisha device.

18. An aerosol-generating system according to claim 17, comprising a cartridge comprising an outer shell enclosing the aerosol-forming substrate.

19. An aerosol-generating system according to claim 17, wherein the aerosol-forming substrate comprises shisha molasses.

20. A method for forming an aerosol in a shisha device, the method comprising: (a) generating a beam of IR radiation by means of a photonic device, (b) directing the beam of IR radiation from the photonic device to an aerosol-forming substrate received in a receptacle of the shisha device, (c) heating the aerosol-forming substrate received in the receptacle of the shisha device by the beam of IR radiation.

Description

[0135] FIG. 1 shows a shisha device including an aerosol generating element of the invention;

[0136] FIG. 2 shows an aerosol generating element of the invention according to an embodiment;

[0137] FIGS. 3A and 3B show an aerosol generating element of the invention according to another embodiment;

[0138] FIG. 4A shows an aerosol generating element of the invention according to another embodiment;

[0139] FIG. 4B shows an aerosol generating element of the invention according to another embodiment;

[0140] FIG. 5A shows a shisha device on the invention according to an embodiment, the shisha device comprising an aerosol-generating element of the invention;

[0141] FIG. 5B shows a control unit for use with the aerosol generating element of the invention, and

[0142] FIG. 6 shows an IR spectrum of glycerol.

[0143] A shisha device 100 comprises an aerosol-generating element 10 configured to receive an aerosol-forming substrate 20 (not shown). The aerosol-generating element 10 may heat the aerosol-forming substrate 20, for example, by means of IR radiation as discussed below with respect to FIG. 2, to generate an aerosol. In use, the generated aerosol flows through an aerosol conduit. The aerosol conduit may be provided as part of a stem pipe 34. The aerosol conduit comprises a proximal end portion defining a proximal opening 42 positioned to receive airflow from the aerosol-generating element 10 and a distal end portion defining a distal opening 44 positioned in an interior of a vessel 46.

[0144] The stem pipe 34 is in fluid communication with the vessel 46. An airflow channel is defined between the aerosol-generating element 10 and the interior of the vessel 46. In particular, the aerosol-generating element 10 is in fluid communication with a vessel 46, by means of stem pipe 34 at least partially defining the airflow channel. The interior of the vessel 46 comprises an upper volume 48 for head space and a lower volume 50 for liquid. A hose 52 is in fluid communication with the upper volume 48 through a head space outlet 54 formed in a side of the vessel 46 above a liquid line. A mouthpiece 56 is coupled to hose 52 for a user of the device 100.

[0145] Generated aerosol may flow through the aerosol-generating element 10, through the air flow channel via the stem pipe 34 into the lower volume 49. The aerosol may pass through liquid in the lower volume 49 and rise into the upper volume 48. Puffing by a user on a mouthpiece 56 of the hose 52 may draw the aerosol in the upper volume 48 through the head space outlet 54, into the hose 20 for inhalation. In particular, negative pressure at the mouthpiece 56 may translate into negative pressure at head space outlet 54 causing airflow through the aerosol-generating element 10 and stem pipe 34.

[0146] FIG. 2 shows an embodiment of an aerosol-generating element 10 of the invention for generating an aerosol as part of a shisha device 100 of FIG. 1. Aerosol-generating element 10 comprises a photonic device 14 configured to generate and emit a beam of IR radiation 16. In the embodiment of FIG. 2, the beam of IR radiation 16 is generated by an IR laser diode emitting radiation with a wavelength of between 1300 nanometers and 2000 nanometers at a power of between 1 Watt and 20 Watts. The aerosol-generating element 10 further comprises a receptacle 18 for receiving an aerosol-forming substrate 20. The aerosol-generating element 10 is arranged to heat the aerosol-forming substrate 20 by directing the beam of IR radiation 16 from photonic device 14 onto the aerosol-forming substrate 20 received in the receptacle 18. An optical element 22 is located in a path of the beam of IR radiation 16 between the photonic device 14 and the receptacle 18. The optical element 22 is configured to manipulate the beam of IR radiation 16. In the embodiment of FIG. 2 optical element 22 comprises a curved mirror for manipulating the beam of IR radiation 16 by reflecting the beam 16 such that the beam 16 changes direction. Preferably, the radius of the curved mirror is not fixed but rather can be manipulated dynamically by means of, for example, water or air pressure.

[0147] Optical element 22 is mounted in the aerosol-generating element 10 by means of an optical mount 24. In the embodiment shown in FIG. 2, the beam of IR radiation 16 comprises an incident beam of IR radiation propagating from the photonic device 14 towards the curved mirror and a reflected beam of IR radiation propagating from the curved mirror to the receptacle 18. The curved mirror reflects the beam of IR radiation 16, changing the direction of the beam to a new direction, which direction is at an angle of approximately 90 degrees relative to the original direction of the beam. Thus, there is an angle of approximately 90 degrees between the incident beam of IR radiation and the reflected beam of IR radiation.

[0148] However, other angles of reflection may be adjusted if desired. The optical mount 24 may be movable in order to adjust different angles of reflection. The position on the aerosol-forming substrate 20 at which the beam of IR radiation 16 irradiates the substrate may be manipulated dynamically by movable optical mount 24. For example, the angle of rotation of the curved mirror with respect to the incident IR beam can be manipulated using a movable optical mount 24. For example, the movable optical mount 24 may comprise a microstructured assembly of stepper motors. Thus, selective heating of discrete portions of the aerosol-forming substrate 20 may be achieved. Selective heating may therefore enable sequential heating of different portions of the aerosol-forming substrate 20 to be accomplished.

[0149] The embodiment of FIG. 2 further comprises a window 26 located at a position in between optical element 22 and the receptacle 18 and being substantially transparent to the beam of IR radiation 16. The reflected beam of IR radiation 16 is transmitted into the receptacle 18 through window 26. Window 26 prevents accumulation of residues on the surface of the laser diode and on the curved mirror.

[0150] FIG. 2 further indicates several details of a working example of the aerosol-generating element 10 in a shisha device 12.

[0151] For allowing airflow into the device, the receptacle 18 comprises at least one air inlet 28. Within the receptacle 18, there may be received the aerosol-forming substrate 20. The aerosol-forming substrate 20 may be provided as part of an aerosol-generating article provided within a capsule 30. In some embodiments, a lid of the capsule 30 may be opened or removed prior to heating. In some embodiments, such as, for example, the illustrated embodiment, the capsule 30 is placed at a distance of up to 5 centimeters from the IR laser diode. In some embodiments, such as, for example, the illustrated embodiment, capsule 30 has no lid. This may help to prevent or at least reduce energy losses by the absorption of an interface material. This may also help to maximize direct irradiation of the aerosol-forming substrate 20.

[0152] Upon absorption of the beam of IR radiation 16 the temperature of the aerosol-forming substrate 20 increases until reaching a temperature where vapor is generated and an aerosol is formed in the receptacle 18. A bottom side of capsule 30 is provided with an airflow outlet, such as one or a plurality of apertures 32 for enabling airflow through the capsule 30.

[0153] Generally, air enters receptacle 18 through air inlet 28, passes through aerosol-forming substrate 20, and exits capsule 30 through apertures 32 placed on the bottom side of capsule 30. Subsequently, the generated aerosol passes through the stem pipe 34 into water and accumulates on the headspace of a water basin (not shown in FIG. 2). The aerosol then passes through a headspace outlet, through a hose to a mouthpiece (features not shown in FIG. 1) where the aerosol may be inhaled by a user.

[0154] FIGS. 3A and 3B show another embodiment of parts of an aerosol-generating element 10 of the invention. The receptacle is not shown in FIGS. 3A and 3B. In contrast to the embodiment of FIG. 2, optical element 22 of the embodiment of FIGS. 3A and 3B comprises a convex lens. As can be seen from FIGS. 3A and 3B the convex lens of optical element 22 manipulates the beam of IR radiation 16 to converge after passing through the optical element 22. Converging and thus focusing of the beam of IR radiation 16 increases the energy density of the IR radiation beam 16. A focused beam allows for a rapid depletion of specific areas of the aerosol-forming substrate 20.

[0155] Further, optical element 22 comprises a movable optical mount 24 for dynamically manipulating the trajectory of the beam of IR radiation 16. This is visualized by the different orientations of the axis of the convex lens of optical element 22 in FIGS. 3A and 3B. Thus, FIGS. 3A and 3B show two of a number of different configurations of the optical element as may be adjusted via the movable optical mount 24. Movement of the movable optical mount 24 may be realized by stepper motors. As can be seen from FIGS. 3A and 3B, movement of optical mount 24 manipulates the trajectory of the focused beam 16. Manipulating the trajectory of the focused beam of IR radiation 16 manipulates where exactly the beam of IR radiation 16 will fall incident on the aerosol-forming substrate 20. As a consequence, aerosol-forming substrate 20 can be irradiated in a selective fashion. The aerosol-forming substrate 20 may therefore be irradiated in a sequential fashion. The pace at which the beam trajectory is manipulated may be set either by a manufacturer or by the user according to their own preference. Such a configuration may be particularly useful for a puff on demand shisha system.

[0156] FIG. 4A shows another embodiment of parts of an aerosol-generating element 10 of the invention. Again, the receptacle is not shown in FIG. 4A. The aerosol-forming substrate 20 is provided within an open lid capsule 30. Other than in the previously described embodiments, in the embodiment of FIG. 4A optical element 22 comprises a concave lens. As can be seen from FIG. 4A the concave lens of optical element 22 manipulates the beam of IR radiation 16 to diverge the beam of IR radiation 16 after having passed through optical element 22. Such a configuration is particularly useful to maintain the substrate at the correct temperature for long time intervals where no puffing occurs, such as pre-heat time periods or in between puffs.

[0157] The aerosol-generating element 10 of the embodiment of FIG. 4A further comprises an additional electrical heating means. The additional electrical heating means comprises a resistive heating means 36. In this embodiment, the beam of IR radiation 16 is conceived as a depletion agent, meaning that aerosol formation takes place substantially only where the beam of IR radiation 16 irradiates the aerosol-forming substrate 20. The resistive heating means 36 maintains the substrate at a constant temperature below a vaporization temperature of the aerosol-forming substrate. The IR heating means provides the additional energy needed to bring one or more compounds of the aerosol-forming substrate 20 to a temperature at or above the vaporization temperature, to generate aerosol.

[0158] FIG. 4B shows another embodiment of parts of an aerosol-generating element 10 of the invention. Again, the receptacle is not shown in FIG. 3B. The embodiment of FIG. 4B is similar to the embodiment of FIG. 4A. The focused beam of IR radiation 16 is conceived as a depletion agent and aerosol formation takes place substantially only at a distinct portion of the aerosol-forming substrate 20 where the focused beam of IR radiation 16 irradiates the aerosol-forming substrate 20.

[0159] The embodiment of FIG. 3B differs from the embodiment of FIG. 4A in that the optical element 22 of FIG. 4B includes a convex lens instead of a concave lens.

[0160] Optical element 22 of FIG. 4B comprises a movable optical mount 24 for dynamically manipulating the trajectory of the beam of IR radiation 16. This configuration is similar to the configuration of the optical element 22 and movable optical mount 24 of the embodiment of FIGS. 3A and 3B.

[0161] The aerosol-forming substrate 20 may therefore be irradiated by the beam of IR radiation 16 in a sequential fashion.

[0162] FIGS. 5A and 5B show a control unit 38 for use with the aerosol-generating element 10 of the invention. Control unit 38 may maximize the ritual preservation in the non-charcoal operated shisha device 12 of the invention.

[0163] FIG. 5A shows in side view control unit 38 being located on top of the aerosol-generating element 10. Further, stem pipe 34 of shisha device 12 is indicated. FIG. 5B shows control unit 38 in top view comprising a user interface 40. The user interface 40 comprises a display. The display visualizes heated areas of the aerosol-forming substrate by means of a contour map. Additionally, the display may show which parts of the aerosol-forming substrate 20 have already been consumed. The display further has the function of a user input means, in the form of a touch screen. Accordingly, when control unit 38 is used, for example, with embodiments wherein the aerosol-generating element 10 comprises means for manipulating the beam of IR radiation 16, such as, for example, the embodiment shown in FIGS. 3A and 3B, the user can input which area of the aerosol-forming substrate 20 should be heated. For example, a user may tap or press and hold an area on the display touch screen to control a position to which the IR beam of radiation 16 is directed. By this action, the stepper motors of the movable optical mount 24 actively direct the beam of IR radiation 16 to the signalled point in the aerosol-forming substrate 20.

[0164] A typical substrate used with shisha devices, such as Al-Fakher double apple molasses, may have a composition of, for example, 15 to 30 percent of tobacco, 45 to 55 percent of glycerol and 15 to 30 percent of sugar. As can be seen in the IR spectrum of glycerol depicted in FIG. 6 (from Xu, M., Wang, X., Jin, B. and Ren, H. Micromachines 2014, 6 (2), 186-195) glycerol has strong absorption bands in the range between 1300 and 2000 nanometers. Accordingly a suitable IR emitter to be used with the shisha device of the present invention may be, for example, a laser diode able to emit light at a wavelength of between 1300 and 2000 nanometers.

[0165] In some embodiments, in order to allow for appropriate use of the shisha device, the IR laser diode should be able to pre-heat the exposed part of the substrate from room-temperature up to a target temperature of about 200 centigrade within about 4 minutes. After this pre-heat phase, a constant evaporation over typically usage period of about 40 minutes should be facilitated by the heating power of the IR emitter.

[0166] Assuming that about a third of the total substrate material, that is the material at the surface of the substrate, is exposed to the light and heated via IR radiation, it can be concluded that the IR laser diode should provide a pre-heating power of between 7 and 20 watts.

[0167] After the target temperature of 200 centigrade is reached, a shisha is typically used for about 40 minutes and the operating temperature needs to be kept constant during this usage period at the target temperature. In this usage period typically a total of 2.8 grams of the molasses substrate is evaporated. Given the above composition of the Al-Fakher double apple molasses, for such evaporation a continuous reduced radiation power of between 1 to 3 watts is required.

[0168] In the given example the power density requirements for pre-heating Al-Fakher double apple molasses within 4 minutes to a target temperature of 200 centigrades is about 1 to 1.5 watts per square centimeter. During use of the shisha device the power density of the IR laser diode may be reduced to about 0.3 to 0.7 watts per square centimetre.