AEROSOL GENERATOR HAVING A SANDWICH CONSTRUCTION

Abstract

An aerosol generator includes a carrier structure having an opening, a mesh membrane covering the opening and overlaying an upper surface of the carrier structure, and a closing ring arranged on an upper surface of the mesh membrane that faces away from the carrier structure. The mesh membrane includes at least two gluing openings extending through the mesh membrane and distributed evenly around a circumference of the mesh membrane. Cured adhesive columns protrude through the gluing openings and mechanically connect an adhesive layer located below the mesh membrane that is bonded to the upper surface of the carrier structure to an adhesive layer located above the mesh membrane that is bonded to a lower surface of the closing ring. The adhesive columns mechanically connect the mesh membrane to the carrier structure and the closing ring.

Claims

1-12. (canceled)

13. An aerosol generator for use in a nebulizer for aerosolization of a fluid comprising: a carrier structure having a concentric, continuous opening; a mesh membrane covering the opening and overlaying an upper surface of the carrier structure; a closing ring arranged on an upper surface of the mesh membrane that faces away from the carrier structure, wherein: the mesh membrane includes at least two gluing openings extending from the upper surface of the mesh membrane to a lower surface of the mesh membrane that faces the carrier structure and distributed evenly around a circumference of the mesh membrane, and cured adhesive columns protruding through the gluing openings; the adhesive columns mechanically connect an adhesive layer that lies below the lower surface of the mesh membrane and is bonded to the upper surface of the carrier structure facing the mesh membrane with an adhesive layer that lies above the upper surface of the mesh membrane and is bonded to a lower surface of the closing ring facing the mesh membrane; and the adhesive columns mechanically connect the mesh membrane to the carrier structure and the closing ring.

14. The aerosol generator according to claim 13, wherein the mesh membrane is not adhesively bonded to the adhesive columns or layers.

15. The aerosol generator according to claim 14, wherein the mesh membrane is made of a material that is not bondable by means of an adhesive approved for contact with active ingredient solutions.

16. The aerosol generator according to claim 14, wherein an introduction of a force from a piezo ceramic into the mesh membrane is affected exclusively via the adhesive columns protruding through the gluing openings.

17. The aerosol generator according to claim 15, wherein the mesh membrane is made of nickel or a fluorine-containing plastic.

18. The aerosol generator according to claim 13, wherein the at least two gluing openings in the mesh membrane comprise three or more gluing openings in the mesh membrane.

19. The aerosol generator according to claim 13, wherein the mesh membrane has a circular outline.

20. The aerosol generator according to claim 13, wherein the at least two gluing openings are arranged on exactly one circle or on exactly two circles around a center point of the opening of the carrier structure.

21. The aerosol generator according to claim 13, wherein the carrier structure comprises a steel disk having an annular piezo ceramic attached on its lower surface facing away from the mesh membrane.

22. The aerosol generator according to claim 13, wherein the carrier structure comprises an annular piezo ceramic.

23. The aerosol generator according to claim 13, wherein the at least two gluing openings are round and a distance from a center of each gluing opening to an edge of the mesh membrane is not less than one and a half times a radius of the gluing openings.

24. The aerosol generator according to claim 13, wherein the adhesive columns and adhesive layers comprise an epoxy resin based adhesive.

25. A method of manufacturing an aerosol generator comprising: providing a mesh membrane, an annular closing ring having an opening and an annular carrier structure having and opening that is concentric to the opening of the annular closing ring, introducing at least two gluing openings spaced evenly along a circumference of the mesh membrane in a desired pattern; applying, on an upper surface of the carrier structure, a ring of adhesive, which encloses the opening, wherein a total adhesive volume of the ring of adhesive is dimensioned larger than the total volume of all the gluing openings of the mesh membrane; placing the mesh membrane over the ring of adhesive and the carrier structure and pressing the mesh membrane toward the upper surface of the carrier structure, wherein the ring of adhesive is pressed and forms a lower adhesive layer between the carrier structure and the mesh membrane, and extends through the gluing openings and forms adhesive dots protruding above an upper surface of the mesh membrane facing away from the carrier structure; placing and pressing the closing ring toward the upper surface of the mesh structure, wherein an upper adhesive layer is formed between the mesh membrane and the closing ring; and allowing the adhesive to cure, wherein the mesh membrane is not adhesively bonded across its entire surface and the introduction of a force from a piezo ceramic into the mesh membrane is effected exclusively via the adhesive columns protruding through the gluing openings.

26. The method according to claim 25, further comprising, after allowing the adhesive to cure, removing protruding adhesive residue.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0031] It is shown in:

[0032] FIG. 1: A cross section through an embodiment of an aerosol generator according to the invention

[0033] FIG. 2: Two possible embodiments of a mesh membrane of an aerosol generator according to the invention in a plan view

[0034] FIG. 3: An illustration of the manufacture of an aerosol generator according to the invention in three partial figures

[0035] FIG. 1 shows a cross section through a possible embodiment of an aerosol generator according to the invention.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

[0036] The mesh membrane 3 is placed on the upper side of the support structure 2 and the closing ring 4 is in turn placed above it. The mesh membrane 3, which as shown has a flat, circular edge area and a convexly curved central area with funnel-shaped pores, has, in the flat outer area, a plurality of circumferentially arranged gluing openings that go through from the top to the bottom and are each filled by column-like structures 51 made of cured adhesive. The adhesive columns 51 connect a lower adhesive layer 5a to an upper adhesive layer 5b and thus form an adhesive structure which looks like an H lying on its side in cross-section. The adhesive layers 5a, 5b are bonded to the adjacent components made of a material suitable for bonding, namely the carrier structure 2 in the case of the lower adhesive layer 5a and the closing ring 4 in the case of the upper adhesive layer 5b. In order to guarantee the most harmonious possible vibration behavior of the aerosol generator, the adhesive layers have as uniform a thickness as possible. For the same reason, excess adhesive portions that have protruded laterally over the outer ring 4 or the mesh membrane 3 are preferably removed during the production according to the invention.

[0037] In two partial figures, FIG. 2 shows two possible embodiments of the mesh membrane of the aerosol generator according to the invention in a plan view.

[0038] Partial figure A shows a version with eight round gluing openings 31, which are distributed evenly, i.e. have an angular distance of 45 degrees between adjacent openings 31, around the circumference over the outer area of the mesh membrane 3, which is flat for surface contact on the carrier structure and has a circular outline. The gluing openings in this possible embodiment therefore lie on a concentric circle around the center point of the mesh membrane 3 and taken together form a regular octagon. The specific number of gluing openings has no meaning and is only for illustration. A higher or lower number would be equally conceivable as long as there are at least two or more, preferably three or more, gluing openings. The circular cross-section of the gluing openings shown here also only has a technical advantage insofar as such openings can be easily produced, for example by drilling, and can therefore also be subsequently inserted into a mesh membrane produced in a different way. However, if mesh membranes produced by means of casting or electro-galvanic deposition methods are used, gluing openings with other cross-sections, for example square, polygonal or in the shape of a segment of a circular ring, could equally be used.

[0039] Subfigure B shows an embodiment with gluing openings 31 arranged on two concentric rings around the center point of the mesh membrane 3, four gluing openings 31 being located on each of the two rings. The openings within a ring are angularly spaced 90 degrees between neighbors, and the openings of the two rings are offset by 45 degrees from each other.

[0040] The mechanical coupling properties of the mesh membrane to the carrier structure and thus the vibration properties and the shape of the standing wave that forms during vibration can be influenced by different combinations of ring radii and the number of gluing openings per ring. As a result, the droplet size distribution can be set as desired within a certain range and optimized with regard to the highest possible proportion of droplets that can enter the pulmonary alveoli (i.e. less than 5 micrometres).

[0041] FIG. 3 illustrates the production of an aerosol generator according to the invention in three subfigures.

[0042] Subfigure A illustrates the steps a) to c) of the manufacturing method according to the invention, i.e. the provision of the components, the carrier structure 2 comprising the piezoceramic, the mesh membrane 3 and the closing ring 4, the introduction of the circumferential gluing openings 31 (indicated by a drill bit) and the application of an annular formation of liquid adhesive 5′ on the upper side of the carrier structure 2, the volume of the adhesive being dimensioned such that it is at least the volume of all gluing openings plus the volume of two layers of adhesive, taking into account any volume change during curing the two layers of adhesive and any losses.

[0043] Subfigure B shows production step d) of the method according to the invention, in which the mesh membrane 3 is placed with its flat outer area on the carrier structure 2 having the adhesive 5’ on it and is pressed on in such a way that the viscous adhesive forms between carrier structure 2 and mesh membrane 3 an adhesive layer 5a as uniformly thick as possible and is pressed into and through the gluing openings 31 and finally forms adhesive spots 5″ protruding from the openings 31 over the upper side of the mesh membrane 3.

[0044] Subfigure C shows the last two production steps, e) and f). In step e), the closing ring 4 is first placed on the upper side of the mesh membrane 3 and the adhesive dots 5′ protruding above it, positioned as desired and then pressed on in such a way that an adhesive layer 5b of the desired thickness is formed as evenly as possible between the mesh membrane 3 and the closing ring 4. In step f) the adhesive is now allowed to harden, which completes the production of the aerosol generator according to the invention.

TABLE-US-00001 List of reference numerals 1 aerosol generator 2 carrier structure/disc 20 opening 3 mesh membrane 31 gluing opening 4 closing ring 5a lower adhesive layer 5b upper adhesive layer 5′, 5″ liquid adhesive

[0045] Although the embodiments of the present disclosure have been described with reference to preferred embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the present disclosure.