Abstract
A mesh for use in a mesh nebuliser. The mesh 300 comprises a first plurality of apertures 310 extending through the mesh 300, the first plurality of apertures 310 having a first average diameter and a second plurality of apertures 320 extending through the mesh 300, the second plurality of apertures 320 having a second average diameter. The first average diameter is different to the second average diameter. The first average diameter may be sized to produce droplet of 1-5 μm, whereas the second average diameter may be sized to produce droplets of 5-30 μm. There is also provided a mesh nebuliser having the present mesh.
Claims
1. A mesh for use in a mesh nebuliser, the mesh comprising: a first plurality of apertures extending through the mesh, the first plurality of apertures having a first average diameter; and at least one second aperture extending through the mesh, the at least one second aperture having a second average diameter, wherein the first average diameter is different to the second average diameter.
2. A mesh as claimed in claim 1, wherein the first plurality of apertures has an average diameter in the range of 0.5-2.5 μm and the at least one second aperture has a diameter in the range of 2.5-15 μm.
3. A mesh as claimed in claim 2, wherein the at least one second aperture has an average diameter in the range of 5-15 μm.
4. A mesh as claimed in claim 1, wherein the first plurality of apertures are sized so as to produce particle sizes with an MMAD in the range of 1-5 μm.
5. A mesh as claimed in claim 1, wherein the at least one second aperture is sized so as to produce particle sizes with an MMAD in the range of 5-30 μm.
6. A mesh as claimed in claim 5, wherein the at least one second aperture is sized so as to produce particle sizes with an MMAD in the range of 10-30 μm.
7. A mesh as claimed in claim 1, wherein the first plurality of apertures is arranged on one side of the mesh and the at least one second aperture is arranged on the other side of the mesh.
8. A mesh as claimed in claim 1, wherein the first plurality of apertures is arranged at the centre of the mesh and wherein the at least one second aperture is arranged on the outside of the first plurality of apertures.
9. A mesh as claimed in claim 1, wherein the first plurality of apertures and the at least one second aperture are distributed evenly on the mesh.
10. A mesh as claimed in claim 1, wherein the first plurality of apertures comprises a range of 0.1%-99% of the apertures by number and the at least one second aperture comprises a range of 0.1%-99% of the apertures by number, wherein the total proportion of both sizes of aperture amounts to 100%.
11. A mesh as claimed in claim 1, further comprising a third plurality of apertures, the apertures having an average diameter of less than 0.5 μm.
12. A mesh as claimed in claim 1, wherein the third plurality of apertures are sized so as to produce particle sizes with an MMAD of less than 1 μm.
13. A mesh nebuliser comprising a mesh as claimed in any of claim 1.
14. A mesh nebuliser as claimed in claim 13 wherein the mesh nebuliser is a passive nebuliser.
15. A mesh nebuliser as claimed in claim 13, wherein the mesh is interchangeable.
Description
[0049] FIG. 1 shows a schematic of the human respiratory system showing where droplets of different diameters impact during inhalation of nebulised fluids;
[0050] FIG. 2 shows a schematic diagram of a mesh nebuliser;
[0051] FIG. 3 shows a schematic mesh with apertures of two different sizes;
[0052] FIG. 4 shows an alternative mesh with apertures of two different sizes;
[0053] FIG. 5 shows an alternative mesh with apertures of two different sizes;
[0054] FIG. 6 shows an alternative mesh with apertures of two different sizes;
[0055] FIG. 7 shows an alternative mesh with apertures of three different sizes;
[0056] FIG. 8 shows an alternative aperture;
[0057] FIG. 9 shows an alternative aperture; and
[0058] FIG. 10 shows an alternative mesh with apertures of two different sizes.
[0059] Turning first to FIG. 1, there is shown a schematic diagram of the human respiratory system showing in outline a person generally indicated 10 having a mouth 20 throat 30, trachea 40 and lungs generally indicated 50. The lungs comprise bronchioles and alveoli. As shown by bracket 100, inhaled aerosol droplets having diameters of over 10 μm will deposit in the mouth 20 and throat 30. As indicated by bracket 110, inhaled aerosol droplets having diameters of 5 to 10 μm will deposit on the trachea, and as indicated by bracket 120, droplets having a particle size of 1 to 5 μm will be deposited in the alveoli of the lungs. Particles of less than 1 μm will generally be exhaled and will generally not be deposited or absorbed into the respiratory system, other than through agglomeration.
[0060] Turning now to FIG. 2, there is shown a schematic of a mesh nebuliser, generally indicated 200. In this example, the mesh nebuliser is a vibratable mesh nebuliser, also referred to as an active nebuliser. The mesh nebuliser comprises a body generally indicated 210 comprising a mouthpiece 220 having a central conduit 230 in communication with a mesh 240. The body 210 contains a reservoir 250 containing a liquid to be nebulised. The mesh 240 is surrounded by a piezoelectric element 260 which is connected to a power source such as a battery 270. A further conduit 280 connects the reservoir 250 to the mesh 240.
[0061] In use a user will inhale on the mouthpiece 220 to draw liquid from the reservoir 250 through the further conduit 280 to the mesh 240. The user may actuate the piezoelectric element 260 such as by pressing a switch to provide power from the power source 270 to the piezoelectric element 260. The piezoelectric element 260 vibrates the mesh 240, which causes the liquid to pass through apertures in the mesh 240 and be turned into aerosol droplets. The aerosol droplets are drawn through the conduit 230 in mouthpiece 220 to the user.
[0062] Turning now to FIG. 3, there is shown an embodiment of mesh according to the present invention, which will be used in a mesh nebuliser. There is shown a mesh generally indicated 300 comprising a first plurality of apertures generally indicated 310 and a second plurality of apertures generally indicated 320. The first plurality of apertures 310 are smaller than the apertures 320. The apertures shown in FIG. 3 are not drawn to scale and are schematic for illustrative purposes. Whilst there may be a total of between 1000 to 4000 apertures on a prior art mesh having a single average diameter size, depending on the choice of aperture sizes, meshes according to the present invention may comprise between 50 and 5000 apertures. The first plurality of apertures may be 50% of the total apertures by number or by area. Mesh 300 is generally circular with opposed planar surfaces, but equally can be of irregular size and shape.
[0063] As shown in FIG. 3, one side of the mesh comprises the first plurality of apertures 310 and the other side of the mesh comprises the second plurality of apertures 320.
[0064] Turning to FIG. 4, there is shown a mesh, generally indicated 400, comprising a first plurality of apertures 410 and a second plurality of apertures 420. The first plurality of apertures 410 are smaller than the apertures 420 Compared to the mesh of FIG. 3 there are a larger number of the second plurality of apertures 420 than there are of the first plurality of apertures 410. In such an embodiment, it may be that the number of apertures of each size may be selected depending on the user experience required. For example, turning to FIG. 2, the liquid to be nebulised in the reservoir 250 may comprise two different elements. For example, the liquid may comprise nicotine which is absorbed into the body through the alveoli of the lungs and a flavour component such as menthol, which will only be tasted if it is deposited onto the mouth of the user. Therefore, the first plurality of apertures 310, 410 may be sized so as to produce droplet sizes of 1 to 5 μm so that a liquid containing nicotine will be nebulised by the mesh and the nicotine will be bioavailable to the user since the droplets are the right size to enter the alveoli where the nicotine will be absorbed.
[0065] Furthermore, the second plurality of apertures 320, 420 may be sized so as to produce nebulised droplets of over 10 μm in diameter, so that those droplets will be deposited in the users mouth. The user will be able to taste the flavour. The respective proportion of first and second pluralities of apertures will be varied depending on the desired user experience and the respective concentrations of the liquid to be nebulised.
[0066] FIG. 5 shows an alternative arrangement of apertures. There is shown a mesh generally indicated 500 comprising a first plurality of apertures 510 arranged towards the centre of the mesh 500, and a second plurality of apertures generally indicated 520 arranged on the outside of the mesh 500. As described with respect to FIGS. 3 and 4, the relative areas of the first and second plurality of apertures, and therefore the number of apertures, can be varied depending on the desired user experience.
[0067] FIG. 6 shows an alternative mesh generally indicated 600 comprising the random distribution of the first and second pluralities of apertures 610 and 620.
[0068] FIG. 7 shows an alternative embodiment with a mesh generally indicated 700 having a first plurality of apertures 710, a second plurality of apertures 720, and a third plurality of apertures 730. Where there are three pluralities of aperture, 710, 720, 730, the distribution and arrangements as shown in FIGS. 3 to 7 could also apply, and that the relative numbers of each aperture size can be varied. The three sizes of aperture could also be distributed randomly as shown in FIG. 6 or concentrically as shown in FIG. 5.
[0069] In the case of there being three sizes of aperture, the third plurality of apertures could be sized so as to produce droplets having a diameter of less than 1 μm. In use, droplets of less than 1 μm will not generally be absorbed by the body and will be exhaled, but will produce a cloud of vapour that could be part of the user experience. There may be further situations where a number of ingredients will want to be targeted to different parts of the respiratory tract and so four or more different aperture sizes may be provided.
[0070] Alternatively, the third plurality of apertures could be sized so that they produces droplets of 2-5 μm. Droplets of such a size will create a throat hit which may be part of the user experience.
[0071] In an alternative embodiment there may be four different average diameters of aperture arranged in any way as described herein. The four average aperture diameters could be size to produce droplets in the range of less than 1 μm, 1-5 μm, 5-10 μm, and greater than 10 μm respectively. Four different average aperture diameters could ensure that that some droplets will create a taste sensation, some droplets will cause a throat hit, some droplets will be absorbed by the alveoli and some droplets will be exhaled. This spectrum of droplet sizes would create the full range of user experience, such as that from smoking a cigarette.
[0072] In respect of the embodiments of mesh described herein the proportion of each average aperture diameter can be varied to optimise the desired user experience. In some aspects of the present invention a mesh nebuliser may be provided which may be an active or passive mesh nebuliser and in some embodiments the mesh may be interchangeable so that a user can experience different experiences whilst using a single nebulizing device.
[0073] A further arrangement of two sizes of aperture is shown in FIG. 10. There is shown a mesh generally indicated 1000 which provides a first plurality of apertures 1010 and a smaller second plurality of apertures 1020. The first plurality of apertures are arrange to extend radially from the centre of the mesh 1000 and the second plurality of apertures 1020 are arranged therebetween. Alternative arrangements could be provided whereby first, second, third or fourth or more pluralities of aperture are arranged radially or in a series of rows or crosshatches depending upon the user experience desired. The arrangement of aperture size could also be influenced based on performance, for example a particular arrangement of the smaller sizes of aperture could prevent them becoming clogged during use. With an active nebuliser the mesh will be generally domed shaped and will flex during use and so a particular arrangement may be beneficial for those embodiments.
[0074] According to a further aspect of the present invention there is shown in FIGS. 8 and 9 alternative apertures which have differently-sized regions, so that a single aperture can produce droplets of various sizes. There is shown in FIG. 8 aperture generally indicated 800 which is generally hourglass shaped and comprises a first region 810 and a second region 820 which has a smaller average diameter than the first region 810. The first and second regions 810 and 820 are conjoined by a narrow region 830.
[0075] As shown in FIG. 9, there is provided an alternative aperture generally indicated 900, which comprises three regions of different average diameter 910, 920 and 930 which are conjoined by narrow region 940. The apertures of FIGS. 8 and 9 may be produced using any known method of manufacture.
