Technical Field

[0001] This disclosure pertains to the field of electronic vaping devices.

Background Art

[0002] In known electronic vaping devices, a substrate containing tobacco or other suitable material is heated to a temperature that is sufficiently high to generate an aerosol from the material but not so high as to cause combustion of the material. Known personal aerosol generating devices comprise a liquid reservoir for containing liquid to be inhaled by a user.

[0003] In order to generate an aerosol, several techniques can be used. Examples of vaporizers comprise a humidifier, a non-thermal vaporizer or a thermal vaporizer. The thermal vaporizer may comprise an electrical heating element for generating an aerosol by heating and vaporising a liquid sensorial media.

[0004] The aerosol generating may be a nebulizer. Nebulizers generate aerosols by breaking apart the liquid into small droplets therefore forming aerosols via a perforated vibrating plate. Typically, the vibrating plate may comprise 1000 to 7000 laser drilled holes. No heating is required. In this case, a personal aerosol generating device may comprise a nebulizer plate arranged above the liquid reservoir and a cotton wick is placed between the reservoir and the nebulizer plate to collect all the liquid from the reservoir by capillarity and deliver it to the nebulizer plate. The nebulizer plate vibrates at the top of the liquid reservoir, and thereby pressures out a mist of very fine droplets through the holes. A nebulizer cavity fluidly connected to an aerosol outlet is formed above the nebulizer plate to create a space for the droplets. A mouthpiece is arranged on top of the device with the aerosol outlet to inhale the aerosols. The liquid contained in the reservoir has to travel through the wick from bottom to top in order to be turned into an aerosol.

[0005] US2020/0245692 discloses a personal aerosol generating device comprising a substantially cylindrically-shaped liquid reservoir. The liquid reservoir has a top end with a fluid opening configured to provide fluid communication of at least a portion of the vaporizable liquid composition stored in the reservoir to an ultrasonic vaporizing component of an associated personal vaporizer. The device comprises a porous capillary wick extending through the fluid opening. The porous capillary wick is positioned such that a lower region of the porous capillary component will be in contact with at least a portion of the vaporizable liquid composition contained in the tank, and, upon installation into the associated personal vaporizer, an upper region of the porous capillary component will be in contact with an ultrasonic vaporizing component of the associated personal vaporizer.

[0006] However, in this configuration, the wick is very long leading to a limited liquid flow to the nebulization area and resulting in dry puffs. These drawbacks lead to an unpleasant customer experience and may increase the risk of inhaling substances from the wick. Some liquid may remain unused at the bottom of the reservoir. This configuration also results in important material costs. [0007] Summary

It is an object of the present invention to alleviate at least partly the above mentioned drawbacks. More particularly, the invention aims at improving liquid flow from the liquid reservoir to the nebulizer plate.

To this end, the present invention concerns a nebulizer device for a personal aerosol generating device, comprising:

- a nebulizer portion and a reservoir for storing liquid to be transformed into aerosols in the nebulizer portion, the nebulizer portion extending along a longitudinal direction from an inlet opening to an outlet opening, a nebulizer plate being disposed in said inlet opening of the nebulizer portion, the nebulizer portion further comprising a nebulizer cavity, an outlet of the nebulizer cavity forming said outlet opening of the nebulizer portion,

- the reservoir comprising a first part and a second part, respectively called side part and bottom part,

- the side part extending from a first end, called top end, to the bottom part,

- the bottom part comprising an exit of the liquid from the reservoir,

- the nebulizer device further comprising a wick arranged in the exit of the bottom part and in contact with the nebulizer plate,

- said top end of the side part being disposed higher than the nebulizer plate in a use position of the nebulizer device.

[0008] The use position of the nebulizer device preferably corresponds to the longitudinal direction oriented vertically with the top end of the side part upwards. Thanks to the reservoir layout partly above the nebulizer plate, the liquid contained in the reservoir is situated higher relative to the nebulizer plate when a user holds the nebulizer device. Therefore, the wick in contact with the nebulizer plate is gravitationally fed and is fed faster than in the reservoir configuration of the state of the art described above. The wick no longer dries during the use of the personal aerosol generating device. Such features lead to a better taste and customer experience, as well as reduced risk potential.

[0009] Furthermore, the wick as well as the personal aerosol generating device can be reduced in length resulting in less raw materials needs and lower material costs.

[0010] The following features can be optionally implemented, separately or in combination one with the others:

- a longitudinal direction of the reservoir is arranged orthogonally with respect to the nebulizer plate;

- a distance between the top end of the side part and the outlet opening of the nebulizer cavity is smaller than a distance between the nebulizer plate and the outlet opening of the nebulizer cavity; - the top end of the side part extends between the outlet opening of the nebulizer cavity and the nebulizer plate;

- the side part rests against a wall of the nebulizer cavity;

- the reservoir comprises at least one liquid guide channel around the wick to deliver the liquid to the entire circumference of the wick;

- the reservoir comprises a housing, said at least one guide channel being formed in said housing;

- the at least one liquid guide channel comprises cuts or slits;

- the cuts or slits are evenly sized and spaced;

- the cuts or slits have a bias in the spacing and size of the cuts or slits.

Brief Description of the Drawings

[0011] Other features and advantages of the nebulizer device disclosed herein will become apparent from the following description of non-limiting embodiments, with reference to the appended drawings, in which:

[0012] Fig. 1 is a schematic longitudinal section view of a personal aerosol generating device.

[0013] Fig. 2 is a schematic view of the reservoir of the personal aerosol generating device of Fig. 1 , the reservoir comprising a side part and a bottom part.

[0014] Fig. 3 shows a schematic view of the reservoir of Fig. 2 wherein the bottom part is shown in longitudinal section.

[0015] Fig. 4 shows a schematic cross-sectional view of the bottom part of the reservoir of Fig.2.

Description of Embodiments

[0016] Fig. 1 schematically shows an example of a personal aerosol generating device 10. For example, the personal aerosol generating device 10 is an electronic cigarette.

[0017] The personal aerosol generating device 10 typically comprises a casing 12, a nebulizer portion 14, a reservoir 16 adapted for storing liquid to be turned into an aerosol and inhaled.

[0018] The casing 12 surrounds the nebulizer portion 14 and the reservoir 16. The casing 12 has for example a cylindrical shape. According to variants, the casing 12 has a parallelepiped shape with straight or rounded sides, a trapezoidal shape or any conceivable shape.

[0019] The casing 12 may comprise or consist of plastic, metal, glass, carbon fiber material, silicon, or ceramic material.

[0020] The nebulizer portion 14 extends along a longitudinal direction L from an inlet opening 20 to an outlet opening 22.

[0021] The nebulizer portion 14 comprises a nebulizer plate 23 configured to turn liquid into an aerosol. The nebulizer plate 23 is typically a perforated vibrating plate. The nebulizer plate 23 sits perpendicular to the longitudinal direction L in the device 10. The personal aerosol generating device 10 may also comprise an electronic circuit, a battery and a switch (not shown) so that a user can turn on and off the nebulizer plate 23 as desired.

[0022] The nebulizer plate 23 is disposed in the inlet opening 20 of the nebulizer portion 14. For example, the nebulizer plate 23 has a perforated disc shape.

[0023] The nebulizer portion 14 comprises a nebulizer cavity 24 wherein liquid is turned into an aerosol between the nebulizer plate 23 and the outlet opening 22 of the nebulizer portion 14. The nebulizer cavity 24 is surrounded by a wall 25 delimited by the casing 12. For example, the nebulizer cavity 24 extends over a length taken parallel to the longitudinal direction L of about 15 % to 25 % of a total length of the personal aerosol generating device 10.

[0024] An outlet 26 of the nebulizer cavity 24 forms said outlet opening 22 of the nebulizer portion 14. The outlet opening 22 of the nebulizer portion 14 may be in the form of a chimney with a portion 28 tighter than the rest of the nebulizer cavity 24. The outlet opening 22 of the nebulizer portion 14 opens preferably at the top of the personal aerosol generating device 10 when the personal aerosol generating device 10 is in a use position. The casing 12 in the vicinity of the outlet opening 22 forms a mouthpiece 29 to be put in the mouth of a user. In an alternative embodiment (not shown), the mouthpiece is detachable from the casing. The personal aerosol generating device thus comprises a mouthpiece portion comprising the nebulizer portion as described above, a reservoir and a casing including an electronic circuit and a battery. In this embodiment, the mouthpiece portion, the reservoir and the casing are distinctive parts that may be connected and disconnected to each other to form the personal aerosol generating device.

[0025] As shown in Fig. 2, the reservoir 16 comprises a housing 31 delimiting a first part 30 and a second part 32, respectively called side part 30 and bottom part 32. The side part 30 extends from a first end 34, called top end 34, to the bottom part 32 of the reservoir 16. The side part 30 is preferably perpendicular to the bottom part 32. The reservoir 16 is thus L-shaped.

[0026] The side part 30 is hollow and is dedicated to store liquid. In the example of Fig.2, the side part 30 rests against a wall 25 of the nebulizer cavity 24. For example, the side part 30 has a longitudinal front side 38 oriented towards the nebulizer cavity 24 and having a rectangular crosssection in the shape of a rectangle portion, and a longitudinal back side 40 oriented towards the casing 12 and having a cross-section in the shape of a circle portion.

[0027] The bottom part 32 has a top side 42 oriented towards the nebulizer cavity 24 and having a longitudinal section in the shape of a rectangle portion. The bottom part 32 has a bottom side 43 parallel to the top side 42. The top side 42 and the bottom side 43 are substantially planar. The top side 42 and the bottom side 43 of the bottom part 32 are connected by an edge 44. The edge 44 is straight on both sides of the bottom part 32 and is rounded at an end 45 of the bottom part 32 opposite to the side part 30.

[0028] Preferably, the side part 30 has a width taken perpendicular to the longitudinal direction L which is smaller than a width of the bottom part 32. [0029] The bottom part 32 comprises an exit 46 of the liquid from the reservoir 16. Preferably, the exit 46 is orthogonal to the longitudinal direction L and is arranged on top of the bottom part 32.

[0030] The reservoir 16 may be made of polymer, preferably Tritan™ Renew.

[0031] A wick 48 is accommodated in the exit 46 of the bottom part 32. When the reservoir 16 is in place in the personal aerosol generating device 10 in a use position of the personal aerosol generating device, the bottom part 32 is below the nebulizer plate 23 and the wick 48 is in contact with the nebulizer plate 23. The wick 48 allows transferring the liquid by capillarity from the reservoir to the nebulizer plate 23. The wick 48 typically has a cylindrical shape. In other embodiments (not shown), the wick may present any other technically feasible shapes.

[0032] The wick material may be made of any well-known materials used, such as cotton, fibreglass, etc.

[0033] The L-shape of the reservoir 16 results in that the top end 34 of the side part 30 is disposed higher than the nebulizer plate 23 in a use position of the personal aerosol generating device 10. In other words, a distance between the top end 34 of the side part 16 and the outlet opening 22 of the nebulizer cavity 24 is smaller than a distance between the nebulizer plate 23 and the outlet opening 22 of the nebulizer cavity 24. The top end 34 of the side part 16 extends between the outlet opening 22 of the nebulizer cavity 24 and the nebulizer plate 23.

[0034] The shape of the reservoir 16 also allows for the personal aerosol generating device 10 shape to be changed to other designs, for example ergonomic designs.

[0035] Preferably, the reservoir 16 is removably arranged in the personal aerosol generating device 10. A user can thus replace it or refill it when necessary.

[0036] In particular embodiments shown in Fig.3 and Fig.4, the reservoir 16 comprises at least one liquid guide channel 50 around the wick 48 to deliver the liquid stored in the reservoir 16 to the entire circumference of the wick 48 due to the asymmetric arrangement of liquid infeed to the wick 48.

[0037] The liquid guide channels 50 as shown in Fig.4 are formed in the housing 31 of the reservoir 16.

[0038] In this example, three guide channels 50 are formed by two first parallel guides 52 extending from the wick 48 to the side part 30 and inside said side part 30 perpendicular to the longitudinal direction L. Two further parallel guides 54 extend on both sides of the two first parallel guides 52 tangential to the wick 48 to the side part 30 thereby creating a narrow corridor for the liquid from the side part 30 to the wick 48.

[0039] The reservoir 16 may further comprise guides 56 circumferentially disposed around the wick 48 and in contact with the wick 48. Those guides 56 form cuts or slits 58 between them allowing for liquid to permeate into the wick 48 at different locations. In Fig.4, the reservoir 16 comprises four guides 56 around the wick 48 that are symmetric two by two with respect to a longitudinal median plane separating the reservoir 16 in two halves. [0040] The cuts or slits 58 may be evenly sized and spaced or have a bias in the spacing and size as shown in Fig .4 allowing to vary their size as desired to create small liquid access into the wick 48 or large liquid access into the wick 48.

[0041] The liquid guide channels 50 may also provide a capillary wicking and holding effect, which enhances the liquid control capabilities within the reservoir 16.

[0042] The personal aerosol generating device 10 may further comprise a spring 60 located below the reservoir 16 along the longitudinal direction L such as the reservoir 16 is sandwiched between the nebulizer plate 23 and the spring 60. The spring 60 allows maintaining the reservoir 16 in place against the nebulizer plate 23. [0043] When the personal aerosol generating device 10 is used, liquid stored in the reservoir 16 is gravitationally fed to the wick 48 and enters in contact with the nebulizer plate 23. The nebulizer plate 23 turns the liquid into an aerosol which passes through the nebulizer plate 23 and a mist 62 is thus formed in the nebulizer cavity 24 above the nebulizer plate 23. The nebulizer cavity 24 is in fluidic communication with the outlet opening 22 on top of the personal aerosol generating device 10. The mist 62 can be inhaled by a user through the outlet opening 22.