Ventilation for shisha device

Abstract

A shisha device (10) comprises an aerosol-generating element (11) for receiving an aerosol-forming substrate (12). The shisha device also comprises a vessel (17) spaced from the aerosol-generating element and defining an interior for housing a volume of liquid. The vessel comprises a head space outlet (15). The shisha device also comprises an aerosol conduit (21) positioned between the aerosol-generating element and the interior of the vessel. The aerosol conduit comprises a proximal end portion defining a proximal opening (24) positioned to receive airflow from the aerosol-generating element, a distal end portion defining a distal opening (26) positioned in the interior of the vessel, and a ventilation opening (30) positioned between the proximal and distal end portions. A ratio between the total aperture area of the ventilation opening and a transverse cross-sectional area of the aerosol conduit positioned proximate to the ventilation opening is at most 1:1000. Applying a negative pressure at the head space outlet causes airflow through the aerosol conduit from the proximal opening to the distal opening and causes airflow through the aerosol conduit from the ventilation opening to the distal opening.

Claims

1. A shisha device comprising: an aerosol-generating element for receiving an aerosol-forming substrate; the aerosol-generating element configured such that the temperature provided is sufficient to generate an aerosol without combusting or burning the aerosol-forming substrate; a vessel spaced from the aerosol-generating element and defining an interior for housing a volume of liquid, the vessel comprising a head space outlet; and an aerosol conduit positioned between the aerosol-generating element and the interior of the vessel, the aerosol conduit comprising: a proximal end portion defining a proximal opening positioned to receive airflow from the aerosol-generating element; a distal end portion defining a distal opening positioned in the interior of the vessel; and a ventilation opening positioned between the proximal and distal end portions, wherein the ventilation opening comprises one or more ventilation apertures and wherein the one or more ventilation apertures have a total aperture area; wherein a ratio between the total aperture area of the ventilation opening and a transverse cross-sectional area of the aerosol conduit positioned proximate to the ventilation opening is at most 1:1000; and wherein applying a negative pressure at the head space outlet causes airflow through the aerosol conduit from the proximal opening downstream to the distal opening and causes ambient air to flow from the ventilation opening, through the aerosol conduit, to the distal opening of the aerosol conduit.

2. The shisha device of claim 1, wherein the ventilation opening comprises one or more: a ambient air aperture.

3. The shisha device of claim 2, wherein the aerosol conduit comprises a cooling element positioned proximate to the one or more ambient air aperture.

4. The shisha device of claim 3, wherein the cooling element comprises an active cooling element.

5. The shisha device of claim 1, wherein the aerosol conduit comprises an accelerating element positioned along the aerosol conduit and configured to accelerate aerosol that flows through the accelerating element.

6. The shisha device of claim 5, wherein the accelerating element comprises one or more ventilation apertures of the ventilation opening.

7. The shisha device of claim 5, wherein the accelerating element comprises a tapered portion and the ventilation opening is positioned in a relatively narrower end portion of the tapered portion of the accelerating element.

8. The shisha device of claim 1, wherein the ventilation opening comprises one or more ventilation apertures forming a ring-shaped opening.

9. The shisha device of claim 1, wherein the ventilation opening comprises a ventilation chamber in fluid communication with one or more ventilation apertures of the ventilation opening.

10. The shisha device of claim 9, wherein the ventilation chamber comprises a vortex element.

11. The shisha device of claim 1, wherein the aerosol conduit comprises a cooling element configured to cool aerosol that flows through the cooling element.

12. The shisha device of claim 11, wherein the cooling element defines at least one of an ambient air aperture of the ventilation opening and a ventilation chamber adjacent to a ventilation aperture of the ventilation opening.

13. The shisha device of claim 1, wherein the ventilation opening comprises one or more ventilation apertures having a total aperture area between 0.2 mm.sup.2 and 7 mm.sup.2.

14. The shisha device of claim 1, wherein the transverse cross-sectional area is located in line with a central point of the ventilation opening.

15. The shisha device of claim 1, wherein the aerosol-generating element and the centre of the ventilation opening are separated by no more than 30 mm.

16. The shisha device of claim 1, wherein the device increases visible aerosol, total aerosol mass, or visible aerosol and total aerosol mass relative to a device that does not include the ventilation opening.

Description

(1) FIG. 1 is a schematic illustration of a shisha device according to an embodiment of the invention.

(2) FIG. 2 is a schematic illustration of an alternative aerosol conduit for use with the shisha device of FIG. 1.

(3) FIG. 3 is a schematic illustration of a shisha device according to another embodiment of the invention.

(4) FIG. 4 is a schematic illustration of an accelerating element for use with the shisha device of FIG. 3.

(5) FIG. 5 is a schematic illustration of an alternative accelerating element for use with the shisha device of FIG. 3.

(6) FIG. 6 is a schematic illustration of an aerosol conduit and a ventilation chamber for use with the shisha device of FIG. 3.

(7) FIG. 7 is a graph showing total aerosol mass for a shisha device having a ventilation opening compared to a shisha device without a ventilation opening.

(8) FIG. 1 shows a shisha device 10 according to an embodiment of the invention. The shisha device 10 comprises an aerosol-generating element 11 configured to receive an aerosol-forming substrate 12. The aerosol-generating element 11 may heat the aerosol-forming substrate 12, for example, by means of an electrical heater (not shown), to generate an aerosol. In use, the generated aerosol flows through an aerosol conduit 21, which includes a ventilation opening 30 in a stem pipe. The aerosol conduit 21 comprises a proximal end portion defining a proximal opening 24 positioned to receive airflow from the aerosol-generating element 11 and a distal end portion defining a distal opening 26 positioned in an interior of a vessel 17. The ventilation opening 30 is positioned between the proximal and distal end portions of aerosol conduit 21.

(9) The aerosol conduit 21 is in fluid communication with the vessel 17. An airflow channel is defined between the aerosol-generating element 11 and the interior of the vessel 17. In particular, the aerosol-generating element 11 is in fluid communication with a vessel 17, by means of aerosol conduit 21 at least partially defining the airflow channel. The interior of the vessel 17 comprises an upper volume 18 for head space and a lower volume 19 for liquid. A hose 20 is in fluid communication with the upper volume 18 through a head space outlet 15 formed in a side of the vessel 17 above a liquid line. A mouthpiece 22 is coupled to hose 20 for a user of the device 10.

(10) Generated aerosol may flow through the aerosol-generating element 11, through the air flow channel via the aerosol conduit 21 into the lower volume 19. The aerosol may pass through liquid in the lower volume 19 and rise into the upper volume 18. Puffing by a user on a mouthpiece of the hose 20 may draw the aerosol in the upper volume 18 through the head space outlet 15, into the hose 20 for inhalation. In particular, negative pressure at the mouthpiece 22 may translate into negative pressure at head space outlet 15 causing airflow through the aerosol-generating element 11 and aerosol conduit 21. Further, the negative pressure causes airflow through the aerosol conduit 21 from the ventilation opening 30 to the distal opening of the aerosol conduit.

(11) The ventilation opening 30 provides ventilation air to aerosol-entrained air from the aerosol-generating element 11. Ventilation air may come from the ambient environment. The ventilation air cools the aerosol-entrained air to facilitate enhanced aerosol production. As illustrated, ventilation opening 30 may be an ambient air aperture positioned adjacent to an ambient air environment.

(12) FIG. 2 shows alternative aerosol conduit 31 for use with the shisha device 10 extending from a proximal end portion defining a proximal opening 25 and a distal end portion defining a distal opening 27. The aerosol conduit 31 includes ventilation opening 32, which includes a ventilation aperture forming a ring-shaped opening. The ring-shaped opening may provide a more homogenous mixture of ventilation air with aerosol-entrained air. The ring-shaped opening may comprise a plurality of smaller openings, such as slits, as shown in FIG. 2. Each of the slits may have any geometrical shape, such as, for example, rectangular, square, circular or ovular. The ventilation opening 32 may comprise more than one ring shaped openings, such as two ring shaped openings as shown in FIG. 2.

(13) FIG. 3 shows a shisha device 100 according to another embodiment of the invention. The shisha device 100 is similar to the shisha device 10 of FIG. 1 and includes an aerosol-generating element 11 and aerosol-forming substrate 12, among other elements shown but not discussed again here. The shisha device 100 differs from the shisha device 10 in that the aerosol conduit 121 includes an accelerating element 114. The aerosol conduit 121 extends from a proximal end portion defining a proximal opening 124 to a distal end portion defining a distal opening 126. The stem pipe portion of the aerosol conduit 121 does not include a ventilation opening in the illustrated embodiment. Instead, the accelerating element 114 comprises a ventilation opening 130. In particular, the accelerating element 114 is a nozzle. A hose 120 is in fluid communication with the aerosol conduit 121. A mouthpiece 122 is coupled to hose 120 for a user of the device 100.

(14) FIG. 4 shows an accelerating element 200 for use with the shisha device 100. In particular, the accelerating element 200 may be positioned along the aerosol conduit 121. The accelerating element 200 is configured to accelerate aerosol that flows through the accelerating element. The accelerating element 200 includes one or more ventilation apertures of ventilation opening 206. The accelerating element 200 extends from a proximal opening of a proximal end portion 202 of the accelerating element 200 to a distal opening of a distal end portion 204 of the accelerating element 200. A ventilation opening 206 is positioned between the proximal and distal end portions 202, 204. In some embodiments, for example the embodiment shown in FIG. 4, the ventilation opening 206 is positioned relatively closer to the proximal opening of the accelerating element 200, which is located proximate to the aerosol-generating element 11 of the shisha device 100 when the accelerating element 200 is installed. Alternatively, the accelerating element 200 may be provided in a different location 208. The location 208 may be a location relatively closer to the distal opening of the accelerating element 200. The location 208 may be a relatively narrow end region of the accelerating element 200. In the illustrated embodiment, the accelerating element 200 is tapered. In some embodiments, a ratio between the total aperture area of the ventilation opening 206, 208 and a transverse cross-sectional area taken through the accelerating element at a central point of the aperture area of the ventilation opening 206, 208 is at most about 1:1000.

(15) FIG. 5 shows an alternative accelerating element 300 for use with the shisha device 100. The accelerating element 300 extends from a proximal opening of a proximal end portion 302 of the accelerating element 300 to a distal opening of a distal end portion 304 of the accelerating element 300. A ventilation opening 306 is positioned between the proximal and distal end portions 202, 204. The accelerating element 300 differs from the accelerating element 200 of FIG. 4 in that only part of the accelerating element 300 is tapered. The accelerating element 300 includes a non-tapered portion 320 and a tapered portion 322 positioned distal to the non-tapered portion. The ventilation opening 306 is positioned on a non-tapered portion 320 of the accelerating element 300. The non-tapered portion 320 of the accelerating element 300 may define a transverse cross-sectional area 310 of the aerosol conduit 121 of shisha device 100 at a central point of the aperture area of the ventilation opening 306. In one embodiment, a ratio between the total aperture area of the ventilation opening 306 and the transverse cross-sectional area 310 is at most about 1:1000.

(16) FIG. 6 shows part of an aerosol conduit 400 and a cooling element 413 that may be used with the shisha device 100. The aerosol conduit 400 includes an accelerating element 414. The accelerating element 414 includes a non-tapered portion 450 and a tapered portion 452 distal to the non-tapered portion. The non-tapered portion 450 may be referred to as a stem pipe or at least a proximal portion of the stem pipe. An internal diameter of the aerosol conduit 400 in the non-tapered portion 450 may be in a range between about 10 mm and about 11 mm. An internal diameter of a narrowest portion of the tapered portion 452 may be about 3 mm. A ventilation aperture 430 is provided along the non-tapered portion 450 of the accelerating element 414. The ventilation aperture 430 is in fluid communication with an ambient air aperture 432 via a ventilation chamber 424 and a ventilation channel 434. Ambient air may enter the ambient air aperture 432, travel through ventilation channel 434, and enter ventilation chamber 424. The ventilation aperture 430 may be about 1 mm in diameter.

(17) The temperature of aerosol entering the aerosol conduit 400 from an aerosol-generating element of the shisha device 100 may be about 160° C. to about 200° C. The cooling element 413 may be used to cool the aerosol to promote the aerosolization process. In addition, the temperature of ventilation air pulled through the ventilation aperture 430 may be regulated using cooling element 413. Pre-cooling the ventilation air may further promote the aerosolization process. Pre-cooling the ventilation air additionally provides increased control over the temperature of the incoming ventilation air and thus over the reproducibility of the aerosolization performance.

(18) The cooling element 413 includes a passive cooling element 420 and an active cooling element 422. The passive cooling element 420 comprises a cooling block, such as an aluminium cooling block. The active cooling element 422 comprises heat pumps (Peltier elements). The Peltier elements each comprise a hot side 442 and a cold side 444. The hot side 442 is thermally coupled to a heatsink comprising plurality of fins 460. The cold side 444 is thermally coupled to the passive cooling element 420. The Peltier element is configured to transfer heat from the cold side 444 to the hot side 442 in a direction away from the cooling block. Ambient air passing the heatsink is heated, drawing heat away from the cooling element 413. The preheated ambient air may enter the aerosol-generating element 11 of the shisha device 100 via an inlet. Ambient airflow entering the ventilation aperture 430 after first entering the cooling element 413 via the ambient air aperture 432 may provide efficient cooling of an aerosol flowing through the aerosol conduit 400. The cooling element 413 may be configured to cool ambient air entering via the ambient air aperture at about 1° C. per Watt using the Peltier elements. Further, a pair of fans (not shown) may be attached to the heatsinks for even further cooling.

(19) In addition, using Peltier elements to pre-cool the ventilation air may reduce the temperature of a ventilation air stream to values below about 20° C. while still maintaining a power consumption of about 10 W, which facilitates compatibility of the shisha device 100 with a battery power source. The high temperature of the hot side 442 of the Peltier element can be reduced by dissipation using the heatsink.

(20) As illustrated, two sealing gaskets 440 extend around the stem pipe 450. The sealing gaskets 440 are positioned between the non-tapered portion 450 of the accelerating element 414 (for example, the stem pipe) and the cooling element 413. In particular, the sealing gaskets 440 are placed at the proximal and distal portions of the cooling block to seal the non-tapered portion 450 (or stem pipe) surrounded by the cooling block to prevent dilution of generated aerosol.

(21) The passive cooling element 420 defines a ventilation chamber 424 and a ventilation channel 434. The ventilation aperture 430 is in fluid communication with the ambient air aperture 432 via the ventilation chamber 424 and the ventilation channel 434. The ventilation chamber 424 may act as a temperature regulated air chamber. The ventilation chamber 424 extends around the ventilation aperture 430. In this embodiment, the ventilation opening is defined by the ventilation aperture 430, the ventilation chamber 424, the ventilation channel 434, and the ambient air aperture 432. Ambient air enters the ventilation channel 434 through the ambient air aperture 432 and flows towards the ventilation chamber 424. The ambient air may be cooled on its way to the chamber by one or more components of the cooling element 413. For example, the ambient air may be cooled by the cooling block. One or both of the ventilation channel 424 and the ventilation channel 434 may comprise a thread like geometry. The thread like geometry further promotes cooling of the ambient air. The ambient air, which may be cooled to about 15° C., for example, remains stagnant in the ventilation chamber 424 between puffs. When a user draws on the mouthpiece 122 of the shisha device 100, the ambient air in the ventilation channel 434 is drawn from the ventilation chamber 424, through the ventilation aperture 430 to the aerosol conduit. At the same time, the negative pressure generated by the user drawing on the mouthpiece 122 of the shisha device causes aerosol generated at the aerosol-generating element 11 to flow through the proximal opening 124 to the distal opening 126 of the aerosol conduit. Ventilation air may mix with aerosol-entrained air in the aerosol conduit 400 before passing through the accelerating element 414. This cools the aerosol, promoting the aerosolization process.

(22) Using the temperature regulated ventilation chamber 424 may advantageously help to compensate for hotter ambient air around the shisha device, for example, up to about 45° C. (for example, in warmer climates, where shisha device is likely to be used). In some embodiments, the shisha device 100 using the aerosol conduit 400 may be used in ambient temperatures in a range between about 15° C. and about 45° C.

(23) Examples of the shisha device with a ventilation opening were made and tested for aerosol production and compared to a shisha device without a ventilation opening. A cartridge filled with 10 g of commercially-available Al-Fakher molasses was heated using a wound-wire heating element set at a constant temperature of 200 degree Celsius. The wound-wire element included a ceramic cylinder having an internal diameter of 27.99±0.01 mm, a length of 41.5 mm, and a thickness of ceramic of 3 mm. The ceramic was obtained from Corning GmbH, Wiesbaden, Germany, under the trade designation “MACOR.” A nozzle made of high temperature epoxy resin with an exit orifice of ϕ about 3 mm was placed at about 55 mm from the heating engine. The epoxy resin was a high temperature epoxy resin obtained from Formlabs, Berlin, Germany. The created aerosol was collected using a total of five Cambridge pads (92 mm diameter) whose was is recorded before and after the smoking experience. The total duration of the experiment corresponded to simulating 105 puffs. In order to achieve the desired puffing experience, four programmable dual syringe pumps (PDSP) manufactured by Pomac BV (Tolbert, Groninen, Netherlands) were used simultaneously to create the following puffing regime: Puff volume: 530 mL Puff duration: 2600 ms Duration between puffs: 17 s

(24) The ventilation aperture consisted of one single hole with a diameter of 1 mm having a total aperture area of about 0.8 mm.sup.2. The aperture was placed at a distance of about 40 mm from the bottom of the heating engine.

(25) The experimental setup was arranged such that only one of the five Cambridge pads collected the generated aerosol at a given moment. Every 21 puffs, a check valve was used to divert the aerosol to the correct Cambridge pad. As a consequence, the production of aerosol can be monitored as a function of time.

(26) FIG. 7 shows a graph 600 of TAM for a shisha device having a ventilation opening 602 compared to TAM for a shisha device without a ventilation opening 604. Using the ventilation opening significantly increased the amount of visible smoke, from a total TAM of 1250 mg to 1700 mg.

(27) The specific embodiments described above are intended to illustrate the invention. However, other embodiments may be made without departing from the scope of the invention as defined in the claims, and it is to be understood that the specific embodiments described above are not intended to be limiting.

(28) As used herein, the singular forms “a,” “an,” and “the” encompass embodiments having plural referents, unless the content clearly dictates otherwise.

(29) As used herein, “or” is generally employed in its sense including “and/or” unless the content clearly dictates otherwise. The term “and/or” means one or all the listed elements or a combination of any two or more of the listed elements.

(30) As used herein, “have,” “having,” “include,” “including,” “comprise,” “comprising” or the like are used in their open-ended sense, and generally mean “including, but not limited to”. It will be understood that “consisting essentially of,” “consisting of,” and the like are subsumed in “comprising,” and the like.

(31) The words “preferred” and “preferably” refer to embodiments of the invention that may afford certain benefits, under certain circumstances. However, other embodiments may also be preferred, under the same or other circumstances. Furthermore, the recitation of one or more preferred embodiments does not imply that other embodiments are not useful and is not intended to exclude other embodiments from the scope of the disclosure, including the claims.