ATOMIZER AND A MESH THEREFOR

Abstract

A mesh for an atomizer assembly is provided, including a first surface, a second surface, and a plurality of nozzles extending between the first surface and the second surface, the first surface being at least partially coated with a hydrophilic coating or the second surface being at least partially coated with a hydrophobic coating, the plurality of nozzles defining an inner surface, and the inner surface being at least partially coated with the hydrophilic coating. An atomizer assembly for an aerosol-generating device, and an aerosol-generating device comprising an atomizer assembly, are also provided.

Claims

1.-13. (canceled)

14. A mesh for an atomizer assembly, comprising: a first surface, a second surface, and a plurality of nozzles extending between the first surface and the second surface, wherein the first surface is at least partially coated with a hydrophilic coating or the second surface is at least partially coated with a hydrophobic coating, wherein the plurality of nozzles defines an inner surface, and wherein the inner surface is at least partially coated with the hydrophilic coating.

15. The mesh for an atomizer assembly according to claim 14, wherein the first surface is at least partially coated with a hydrophilic coating and the second surface is at least partially coated with a hydrophobic coating.

16. The mesh for an atomizer assembly according to claim 14, wherein the whole surface of the first surface, the second surface, or both the first and the second surfaces is coated.

17. The mesh for an atomizer assembly according to claim 14, wherein the hydrophobic coating comprises polyurethane or a super-hydrophobic metal layer or a combination of both.

18. The mesh for an atomizer assembly according to claim 17, wherein the super-hydrophobic metal layer comprises a microporous metal functionalised with carbon chains or a metal mesh functionalised with carbon chains.

19. The mesh for an atomizer assembly according to claim 14, wherein the hydrophilic coating comprises at least one of the following: oxides, 3 polyamide, polyvinyl acetate, cellulose acetate, cotton.

20. The mesh for an atomizer assembly according to claim 14, wherein the hydrophilic coating comprises at least one of the following: SiO.sub.2, Al.sub.2O.sub.3, TiO.sub.2, Ta.sub.2O.sub.5, HfO.sub.2.

21. The mesh for an atomizer assembly according to claim 14, wherein the mesh is made of silicon.

22. The mesh for an atomizer assembly according to claim 14, wherein each nozzle of the plurality of nozzles defines a first opening in the first surface and a second opening in the second surface, and wherein the second opening has a diameter of 2.5 μm to 4 μm.

23. An atomizer assembly for an aerosol-generating device, the atomizer assembly comprising a mesh according to claim 14.

24. The atomizer assembly according to claim 23, further comprising: an elastically deformable element; a cavity disposed between the mesh element and the elastically deformable element; a liquid inlet configured to provide a supply of liquid to be atomized to the cavity; and an actuator configured to oscillate the elastically deformable element.

25. The atomizer assembly according to claim 24, wherein the mesh is disposed such that the first surface of the mesh faces the cavity and the second surface of the mesh faces an outside of the atomizer assembly.

26. An aerosol generating device comprising an atomizer assembly according to claim 23.

Description

[0035] Specific embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings in which:

[0036] FIGS. 1a and 1b are schematic overview of two embodiments of a mesh according to the present invention;

[0037] FIG. 2 is a schematic cross-sectional view of the mesh;

[0038] FIG. 3 is a schematic illustration of an atomizer assembly using the mesh;

[0039] FIG. 4 is a schematic illustration of an aerosol generating device using the mesh.

[0040] FIGS. 1a, 1b and 2 show an example of the mesh 1 according to the present invention. The mesh on FIG. 1a is circular, with a central part with nozzles 2 and a rim without nozzles. FIG. 1b shows a square-shaped mesh 1 with nozzles 2. The shape of the mesh and whether the rim is provided or not depends on the atomizer and on the way the mesh is retained in the atomizer.

[0041] The mesh comprises a plurality of nozzles 2. The nozzles 2 are triangle shaped, with their first opening 6 bigger than their second opening 7, as shown schematically in FIG. 2. The mesh 1 has a first surface 3 which, when positioned within the atomizer assembly 50, is positioned towards the cavity 62 containing the liquid, and a second surface 4 which, when positioned within the atomizer assembly, is positioned away from the cavity 62 containing the liquid.

[0042] Each of the nozzles 2 comprises a first opening 6, through which the liquid enters the nozzle 2, a second opening 7 through which the liquid leaves the nozzle 2, and an inner surface 5 which connects the first opening 6 with the second opening 7.

[0043] The first surface 3 is coated with a hydrophilic coating (not shown). The hydrophilic coating is any one of 3 polyamide, polyvinyl acetate, cellulose acetate or cotton.

[0044] The second surface 4 is coated with a hydrophobic coating. The hydrophobic coating comprises any one of polyurethane (PU) or a layer of a super-hydrophobic metal such as a microporous metal or a metal mesh. The microporous metal or metal mesh include copper or aluminium, functionalised with carbon chains.

[0045] The inner surface 5 of each nozzle is also coated with a hydrophilic coating. The hydrophilic coating is the same as the coating of the first surface.

[0046] FIG. 3 shows a perspective cross-sectional view of an atomiser assembly 50 comprising the mesh 1 of FIGS. 1 and 2. The mesh 1 is received within a mesh housing 52. The atomiser assembly 50 also comprises an elastically deformable element 54 and an actuator 56 arranged to oscillate the elastically deformable element 54. The actuator 56 is a piezoelectric actuator.

[0047] The atomiser assembly 50 also comprises a pre-loading element 58 arranged to compress the actuator 56 between the pre-loading element 58 and the elastically deformable element 54. The pre-loading element 58, the actuator 56 and the elastically deformable element 54 are arranged within an actuator housing 60. The actuator housing 60 is attached to the mesh housing 52 to define a cavity 62 between the mesh 1 and the elastically deformable element 54. The actuator housing 60 defines a liquid inlet 64 for providing a supply of liquid to be atomised to the cavity 62.

[0048] During use, liquid to be atomised is supplied to the cavity 62 through the liquid inlet 64. The actuator 56 oscillates the elastically deformable element 54 to force at least some of the liquid within the cavity 62 through the channels 14 and the nozzles 2 of the mesh 1. The liquid forced through the nozzles 18 of the mesh 1 form droplets. The momentum of the liquid forced through the nozzles 18 to form the droplets carries the droplets away from the mesh 1. Therefore, during use, the atomiser assembly 50 generates an aerosol comprising liquid droplets ejected through the mesh 1.

[0049] The atomizer may be actuated at a resonant frequency. The resonant frequency is a function of one or more of the following: e-liquid viscosity (possibly lowered by increasing its temperature above room temperature and below 100 degrees Celsius); e-liquid surface tension; nozzle diameter and geometry; mesh thickness or rigidity; speed of droplet ejection; amplitude of actuation; atomizer assembly mechanical characteristics. The resonant frequency may be calculated based on a combination of the above factors.

[0050] FIG. 4 shows a cross-sectional view of an aerosol-generating system 70 according to an embodiment of the present invention. The aerosol-generating system 70 comprises an aerosol-generating device 72 and a liquid reservoir 74.

[0051] The aerosol-generating device 72 comprises a housing 76 comprising a first housing portion 78 and a second housing portion 80. A controller 82 and a power supply 84 comprising a battery are positioned within the first housing portion 78. A mouthpiece 85 defining a mouthpiece channel 87 is connectable to the second housing portion 80.

[0052] The second housing portion 80 defines a liquid reservoir chamber 86 for receiving the liquid reservoir 74. The first housing portion 78 is detachable from the second housing portion 80 to allow replacement of the liquid reservoir 74.

[0053] The aerosol-generating device 72 also comprises a device connector 88 positioned within the liquid reservoir chamber 86 for engagement with a reservoir connector 90 that forms part of the liquid reservoir 74.

[0054] The aerosol-generating device 72 comprises the atomiser assembly 50 of FIG. 3 positioned within the second housing portion 80. The liquid inlet 64 of the atomiser assembly 50 is in fluid communication with the device connector 88. The mesh 1 of the atomiser assembly 50 is positioned within an aerosol chamber 92 defined by the second housing portion 80.

[0055] The liquid reservoir 74 comprises a container 94 and a liquid aerosol-forming substrate 96 positioned within the container 94. When the reservoir connector 90 is engaged with the device connector 88, liquid aerosol-forming substrate 96 from the liquid reservoir 74 is supplied to the cavity 62 of the atomiser assembly 50 through the reservoir connector 90, the device connector 88, and the liquid inlet 64 of the atomiser assembly 50.

[0056] When the first housing portion 78 is connected to the second housing portion 80, the controller 82 controls a supply of power from the power supply 84 to the actuator 56 to eject droplets of the liquid aerosol-forming substrate 96 into the aerosol chamber 92 from the mesh 1.

[0057] The second housing portion 80 defines an air inlet 98 and an air outlet 100 each in fluid communication with the aerosol chamber 92. During use, a user draws on the mouthpiece 85 to draw air into the aerosol chamber 92 through the air inlet 98. The air flows through the aerosol chamber 92 where droplets of liquid aerosol-forming substrate 96 ejected from the mesh 1 are entrained within the airflow to form an aerosol. The aerosol flows out of the aerosol chamber 92 through the air outlet 100 and is delivered to the user through the mouthpiece channel 87.

[0058] The aerosol-generating device 72 also comprises an airflow sensor 102 positioned within the aerosol chamber 92. The airflow sensor 102 is arranged to provide a signal to the controller 82 indicative of a user drawing on the mouthpiece 85. The controller 82 is arranged to supply power from the power supply 84 to the actuator 56 of the atomiser assembly 50 only when the controller receives a signal from the airflow sensor 102 indicative of a user drawing on the mouthpiece 85.