Flow-optimised mouthpiece, having an air gap, for an inhaler

Abstract

The invention relates to a mouthpiece (1) for an inhaler, comprising: an in particular substantially hollow cylindrical connection portion (2), which defines a longitudinal axis (A), for connecting the mouthpiece to the inhaler, in particular by placement on a connecting piece of the inhaler; a contact portion (4), which is suitably shaped in order to be surrounded by the lips by a user of the inhaler; and a central portion (3), lying therebetween; wherein the mouthpiece (1) comprises one or more air gaps (5, 51, 52), through which, when inhaling, air can enter an interior of the mouthpiece, wherein the intake opening surface of the air gap (5, 51, 52) or an overall intake opening surface area of all air gaps (5, 51, 52) in total is 25 mm2 or less, and an angular extension of the air gap (5, 51, 52) or an overall angular extension of all air gaps (5, 51, 52) in total is 60° or more. The invention also relates to the production of such a mouthpiece and an inhaler having such a mouthpiece.

Description

[0001] Flow-optimized mouthpiece with air gap for an inhaler

[0002] The present invention relates to a mouthpiece with an air gap for an inhaler, comprising a connection section defining a longitudinal axis, in particular a substantially hollow cylindrical connection section for connecting the mouthpiece to the inhaler, in particular by plugging it onto a connection piece or a connection piece of the inhaler, a contact section which is suitably shaped to be grasped by a user of the inhaler with the lips, and an intermediate section, wherein the mouthpiece has one or more air gaps through which air can enter an interior of the mouthpiece during inhalation.

[0003] Furthermore, the invention relates to an inhaler with such a mouthpiece, in particular a nebulizer, which encloses an aerosol generator held in its interior by a seal and a holding structure and in particular a connecting piece or a connecting support for the mouthpiece is formed on an outlet side of the aerosol generator.

[0004] The invention also relates to the manufacture of a mouthpiece according to the invention.

[0005] For the medical treatment of respiratory diseases, inhalation therapies are used, in which the patient inhales a nebulized medication solution. A nebulizer can be used for this purpose. It contains an aerosol generator for aerosolizing, or atomizing, a medication solution and a mouthpiece for establishing an at least largely sealed connection with the patient's airways. The aerosol generator can be a metal membrane with micrometer-sized pores. This is caused to vibrate by an electrically excited, circular piezoelectric crystal, thereby atomizing a medication solution supplied from a reservoir into micrometer-fine aerosol droplets.

[0006] The mouthpiece connected to the nebulizer unit is typically ergonomically designed so that it can be comfortably gripped by the patient's lips, creating a largely airtight seal. During inhalation, the patient inhales the volume of air containing medication delivered to the mouthpiece from the outlet of the nebulizer unit, where it exerts its effect directly on the bronchi and lungs. The nebulizer unit typically features axial ventilation slots through which fresh air flows to the aerosol during inhalation and through which used air can escape during exhalation.

[0007] In advanced inhalation devices, aerosol delivery is triggered by the patient's breathing activity, meaning medication delivery only occurs during the inhalation phase. For this purpose, the applicant's inhalation devices can register breathing activity via pressure or flow sensors via a so-called flow channel that ends inside the mouthpiece, and transmit corresponding commands to a control unit.

[0008] In nebulizer units with associated mouthpieces according to the state of the art, the aerosol-air mixture drawn in by the patient during inhalation has a divergent flow profile at the outlet of the nebulizer unit, i.e., a conically widening flow profile in the main direction of propagation, with superimposed turbulence. Such a flow profile leads to the effect that aerosol droplets precipitate and accumulate on the walls in the area of ​​the mouthpiece. The active ingredient contained in these droplets therefore does not reach the intended site of action in the bronchi or lungs, but instead flows either into the patient's oral cavity, where it is absorbed without the intended effect, or back into the nebulizer unit, which thereby reduces its aerosol generation capacity and exposes it to continuous contamination.These drug losses particularly impair therapeutic success because they result in uncontrolled and uncertain drug doses absorbed by the patient through the respiratory tract. Furthermore, adverse health effects cannot be ruled out if the drug comes into contact with tissues for which it is not intended, such as the mucous membranes in the patient's oral cavity.

[0009] In published patent application DE 10 2018 112 711 A1, the applicant therefore proposes providing at least one circumferentially extending air-permeable gap through which outside air is drawn in during inhalation. This air flow forms an enveloping air stream inside the mouthpiece that clings to the inner surface of the mouthpiece and mixes only slightly or not at all with the aerosol, preventing the aerosol particles from coming into contact with the inner walls of the mouthpiece. For this purpose, an air gap extending, if possible, over the entire circumference is recommended, and should, in particular, have a spiral shape.

[0010] However, this results in several disadvantages. Firstly, the gap causes the breathing resistance of the mouthpiece to be very low, so that the drawn-in air takes up too large a proportion of the patient's inhaled air volume, which disadvantageously reduces the aerosol concentration. Secondly, complete removal of the aerosol from the outlet area of ​​the aerosol generator is not guaranteed. Furthermore, breath-controlled triggering of the medication solution nebulization is no longer reliably possible.

[0011] The present invention therefore aims to solve the problem of finding a simple and cost-effective mouthpiece which prevents the deposition of aerosol droplets on the inner walls of the mouthpiece and thereby avoids the disadvantages described above. In particular, the most complete aerosol transport from the area of ​​the aerosol generator outlet should be guaranteed.

[0012] This is achieved with a mouthpiece according to claim 1 and an inhaler using such a mouthpiece, in particular a nebulizer, according to claim 14. The mouthpiece according to the invention can be manufactured according to the method according to claim 13.

[0013] According to the invention, the mouthpiece consisting of a connecting section, a middle or intermediate section and a contact section has at least one circumferential air gap which has a minimum angular extension of 60°, but at the same time a total inlet opening area of ​​less than 25 mm 2. Experiments conducted by the inventors have shown that a shorter air gap does not produce an enveloping airflow that sufficiently encloses the aerosol flow, and that a larger inlet opening area reduces the breathing resistance of the mouthpiece too much. In embodiments in which the gap area changes radially, as seen from the mouthpiece's longitudinal axis, the relevant inlet opening area is the minimum of the gap area in its radial direction.

[0014] The air gap should be positioned as far upstream as possible in the longitudinal direction of the mouthpiece (relative to the flow direction during inhalation). For this purpose, it is advisable to provide the air gap in the connection section. In the case of a mouthpiece that is permanently connected to the inhaler, e.g. by welding, the air gap can be located near the open end of the connection section. With an interchangeable mouthpiece, a preferred embodiment of the present invention, this is generally not possible, since such a mouthpiece is usually inserted onto or into a nozzle-like connection piece of the inhaler for (detachable) connection to the inhaler. Since the connection section and the connection piece at least partially overlap, it must be ensured that the air gap is not inadvertently closed.

[0015] First, the air gap can be positioned as far as possible from the open end of the connecting section, i.e., in the area of ​​the transition to the middle section. Alternatively, the gap can be positioned in the middle section near the transition or even directly in the transition. Alternatively or additionally, projections are provided between the air gap and the open end of the connecting section. These projections serve as a stop and prevent the mouthpiece from being accidentally pushed too far onto or into the connecting piece.

[0016] The mouthpiece can be produced using the manufacturing method according to the invention. A mouthpiece blank without an air gap is provided, and the air gap is introduced at the intended location of the connecting section or the central section using a suitable tool, in particular a saw, a CNC milling machine, or a laser.

[0017] This is preferably done in such a way that the two end faces, i.e., the opposing short boundary surfaces of the elongated air gap, lie in the same plane intersecting the inner surface of the mouthpiece. This makes manufacturing particularly simple, since the air gap can be introduced into the mouthpiece using a straight machining tool, such as a saw blade or laser beam.

[0018] The manufacturing method according to the invention can be applied to newly manufactured mouthpiece blanks as well as to mouthpieces manufactured some time ago or even to those already in use. It is therefore possible to convert a conventional mouthpiece without an air gap into one according to the invention.

[0019] In the following, advantageous embodiments of the mouthpiece according to the invention are presented, which can be combined with each other in a suitable form, provided that they do not exclude each other.

[0020] In order to increase the circumferential extent of the air sucked into the interior of the mouthpiece through the air gap(s) during inhalation, and thus to improve the enclosure of the aerosol-containing central air stream by the low-aerosol outer envelope air stream, it is proposed for preferred embodiments to use more than one air gap. The air gaps are preferably evenly distributed over a closed circumferential line of the mouthpiece, and in particular are all located in a plane intersecting the longitudinal axis of the mouthpiece, which is formed by the cylinder axis of the essentially cylindrical mouthpiece. This plane is particularly preferably orthogonal to the longitudinal axis. "Evenly distributed" here refers to the centers of the air gaps in their longitudinal direction, i.e. with two air gaps, the gap centers are preferably essentially diametrically opposite one another, with three air gaps they are approximately diametrically opposite one another.120 degrees to each other and thus generally with a number of k air gaps distributed at 360 / degrees to each other on the closed circumferential line.

[0021] The inventive limitation of the inlet opening area refers to the total area, i.e., the sum of the individual areas of all air gaps, in the case of multiple air gaps. The same applies, mutatis mutandis, to the specification for the minimum angular extension.

[0022] In preferred embodiments of the invention, the air gap(s) has a width of 1 mm or less, in particular between 0.5 and 1.0 mm, particularly preferably between 0.7 and 0.9 mm, for example 0.85 mm. Accordingly, the length of such air gaps, measured along the (curved) surface of the mouthpiece, corresponds to 25 mm - 50 mm or less.

[0023] The boundary surfaces of the gap, or one of the gaps, can be oriented radially, as seen from the longitudinal axis of the nozzle. However, they can also be oriented at an angle to the respective radial direction. This can achieve a nozzle effect, since the effective inlet opening area on the inside of the nozzle is then smaller than the opening area of ​​the gap on the outside. In these embodiments, the relevant inlet opening area is the gap area on the inside of the nozzle, since the gap area is minimal here.

[0024] In other embodiments, the opposing long boundary surfaces are parallel to each other and oriented radially, i.e., in particular, perpendicular to the longitudinal axis of the mouthpiece, while the end surfaces, i.e., the short boundary surfaces, are inclined relative to the respective radial direction. This is particularly the case in such a way that the end surfaces lie in a plane or, in the case of end surfaces curved transversely to the longitudinal direction of the gap, a straight line exists for each point on each of the end surfaces, which is a tangent to both end surfaces.

[0025] The air gap, or one of the air gaps, is preferably located in an upper side of the mouthpiece facing the user of the inhaler during intended use. This upper air gap preferably has an angular extension of between 45° and 90°, particularly preferably between 50° and 70°, in particular approximately 55°.

[0026] In addition to the upper air gap, in preferred embodiments of the mouthpiece, two lateral air gaps are arranged offset from the upper air gap by approximately 120° relative to the centers of the air gaps in their longitudinal direction. All three air gaps lie in a plane perpendicular to the longitudinal axis of the mouthpiece and particularly preferably have the same gap width of approximately 0.85 millimeters. The lateral air gaps preferably have an angular extension of between 20-50°, in particular approximately 30°.

[0027] In preferred embodiments of the inventive

[0028] The mouthpiece has a length of between 40 and 60 mm, in particular approximately 50 mm. In further preferred embodiments, the width of the mouthpiece, which is determined by the contact section, which preferably has an oval cross-section, is between 25 mm and 40 mm, in particular between 30 mm and 35 mm. In some embodiments, the height of the mouthpiece, which is determined by the (outer) diameter of the connection section, is between 20 mm and 30 mm, preferably approximately 24 mm.

[0029] In further preferred embodiments, the connection section of the mouthpiece has at least a slight deviation from a hollow cylindrical shape in the form of an outwardly curved, approximately semi-cylindrical bulge or protrusion aligned parallel to the cylinder axis, which is open at its end facing the inhaler and closed at its opposite end facing away from the inhaler. By means of this bulge, the mouthpiece can be connected to a measuring channel of the inhaler. By measuring / monitoring (the temporal course) of the air flow through or the air pressure in the channel, a control unit of the inhaler can carry out a breath-controlled activation of the inhaler, in particular the nebulizer. In the region of the bulge, i.e. in the axial direction in front of or behind it, there is preferably no air gap.

[0030] Further properties, features, and advantages of the present invention will become apparent from the exemplary embodiments explained in more detail below with reference to the figures. These are intended only to illustrate the present invention and are not intended to limit it in any way.

[0031] Figures 1A, 1B: Isometric views of a preferred embodiment of the mouthpiece according to the invention

[0032] Figure 2A: A top view of the embodiment from the

[0033] Figures 1A, 1B.

[0034] Figure 2B: A bottom view of the embodiment of Figures 1A, 1B.

[0035] Figure 2C: A rear view of the lower half of the embodiment of Figures 1A, 1B.

[0036] Figure 3A: A cross-section through the embodiment of the previous figures, wherein the cross-sectional plane coincides with the plane of the air gaps.

[0037] Figure 3B: A longitudinal section through the preferred embodiment along the mirror symmetry plane of the mouthpiece.

[0038] A preferred embodiment of a mouthpiece according to the invention is illustrated in the figures. Fig. 1A shows an isometric view obliquely from the rear, Fig. 1B an isometric view obliquely from the front. As can be seen in these figures, the mouthpiece 1 comprises an approximately hollow cylindrical connecting section 2, which defines the longitudinal axis of the mouthpiece 1 via its cylinder axis A, an oval contact section 4 and, in between, a central section 3 which provides a transition between the hollow cylindrical shape of the connecting section 2 and the contact section 4. In the connecting section 2, near the transition to the central section, three air gaps 51, 52I, 52r can be seen. These comprise an upper air gap 51 in the upper side of the mouthpiece facing the inhaler during intended use, as well as two lateral air gaps 52I, 52r introduced on either side of the connecting section 2.

[0039] The total angular extent covered by the air gaps is approximately 115°, of which an angle a1 of approximately 55° is attributable to the upper air gap 51, and the lateral air gaps 52I, 52r each contribute an angle a2 of approximately 30°. With an inner diameter of 22 mm, this results in a total gap length of 22 mm, and due to the gap width of 0.85 mm for all three gaps, a total inlet opening area of ​​18.7 mm. 2 . Here, the minimum of the gap opening, which varies radially, is selected for both the angular extent and the inlet opening area. This means that, as can be seen in Figure 3A, the radial rays used to determine the angles a1, a2 are adjacent to the inner edges 51a, 51b of the upper gap 51 and 52la, 52lb, 52ra, 52rb of the lateral gaps 52l, 52r.

[0040] As can also be clearly seen in the cross-section shown in Figure 3A, the end faces of the three gaps lie in the same plane E1, E2I, E2r.

[0041] Furthermore, the air gaps 51, 52 all lie in a plane perpendicular to the longitudinal axis of the mouthpiece, which here is formed by the cylinder axis of the connecting section 2. This is particularly clearly visible in the longitudinal section along the plane of symmetry S in Figure 3B. This ensures that the enveloping air flow formed during inhalation, consisting of aerosol droplet-free outside air sucked in through the air gaps 51, 52, is distributed as evenly as possible around the aerosol droplet-containing air originating from the inhaler in order to prevent condensate precipitation inside the mouthpiece as effectively as possible.

[0042] The connecting section 2 has a substantially hollow cylindrical shape, i.e. apart from small deviations, such as the bulge 6, which enables the mouthpiece to be easily plugged onto a complementarily shaped connecting piece of the inhaler, in particular a nebulizer.

[0043] The contact section 4 is ergonomically shaped so that it can be easily grasped by the user's lips and thus an airtight connection can be established between the inhaler and the user's oral cavity.

[0044] The middle section 3 creates a transition between the contact section 4 and the connection section 2, which is geometrically shaped as simply as possible in order to enable simple production and, on the other hand, easy cleaning and, if necessary, sterilization of the mouthpiece.

[0045] Figure 2C shows a detailed rear view of the preferred embodiment of the mouthpiece 1, in which the semi-cylindrical shape of the bulge 6 can be seen. In conjunction with Fig. 1A, it can be seen that the bulge 6, which is open only to the rear, toward the inhaler, forms an air channel when the mouthpiece 1 is plugged onto a connecting piece of the inhaler. This air channel is delimited inwardly by the outer surface of the connecting piece. Using this air channel, a flow or pressure gauge of the inhaler can measure the flow or pressure within the mouthpiece, thus enabling breath-dependent control of the inhaler....

[0046] List of reference symbols

[0047] 1 mouthpiece

[0048] 2 connecting section of 1

[0049] 3 Middle section of 1

[0050] 4 contact section of 1

[0051] 51 upper air gap

[0052] 51a,b inner edges of 51

[0053] 52, 52I, 52r side air gap

[0054] 52la,lb inner edges of 52I

[0055] 52ra,rb inner edges of 52r

[0056] 6 bulge

[0057] 61

[0058] A Longitudinal axis of 1

[0059] S mirror symmetry plane of 1 al opening angle of 51 a2 opening angle of 52

[0060] E1 end face plane of 51

[0061] E11 End face plane of 52I

[0062] E1 r end face plane of 52r

Claims

Patent claims Mouthpiece (1) for an inhaler, comprising: - a connecting section (2) defining a longitudinal axis, in particular a substantially hollow cylindrical section, for connecting the mouthpiece to the inhaler, in particular by plugging it onto a connecting piece of the inhaler, - a contact portion (4) which is suitably shaped to be grasped by a user of the inhaler with the lips, and - an intermediate central section (3), wherein the mouthpiece (1) has one or more air gaps (51, 52) through which air can enter an interior of the mouthpiece during inhalation, characterized in that - an inlet opening area of ​​the air gap (51, 52) or a total inlet opening area of ​​all air gaps (51, 52) taken together 25 mm 2 or less, and - an angular extent of the air gap (51, 52) or a total angular extent of all air gaps (51, 52) taken together is 60° or more. Mouthpiece according to claim 1, characterized in that the air gap (5, 51, 52) extends in a plane perpendicular to the longitudinal axis. Mouthpiece according to claim 1 or 2, characterized in that the air gap (51, 52) in the region of the overlap junction between the connecting section (2) and the middle section (3) in the connecting section (2) or in the middle section (3). Mouthpiece according to one of the preceding claims, characterized in that the opposite end-side boundary surfaces of the air gap (51, 52) lie in one plane. Mouthpiece according to one of the preceding claims, characterized in that the longitudinal boundary surfaces of the air gap (51, 52) are perpendicular to the longitudinal axis. Mouthpiece according to one of the preceding claims, characterized by an upper air gap (51) arranged on an upper side facing the user during intended use, which upper air gap in particular has an angular extension of between 45 and 90°, particularly preferably between 50 and 70°. Mouthpiece according to one of the preceding claims, characterized by two or more air gaps (5, 51, Mouthpiece according to the preceding claim, characterized in that the air gaps are arranged so as to be evenly distributed around the circumference. Mouthpiece according to the preceding claim, characterized in that an upper air gap (51) is provided on an upper side of the mouthpiece (1) facing the user during intended use, and two lateral air gaps (52) are provided, the centers of which are offset from a center of the upper air gap (51) by between 100° and 140°, in particular 120°. Mouthpiece according to one of the preceding claims, characterized in that it - a length of between 40 and 60 mm, in particular approximately 50 mm and - has a width of between 25 and 40 mm, in particular between 30 and 35 mm, wherein the width of the mouthpiece is determined by a width of the contact section (4), - has a height of between 20 and 30 mm, in particular of approximately 24 mm, wherein the height of the mouthpiece is determined by an outer diameter of the connecting section (2). Mouthpiece according to one of the preceding claims, characterized by a hollow bulge (6) of the connecting section (2), which is arranged on an inhaler-side Side (61) is open, but closed on a user-facing side (62).

12. Mouthpiece according to the preceding claim, characterized in that there is no air gap (5, 51, 52) either in the bulge (6) itself or axially in front of it in the user-facing direction.

13. Production of a mouthpiece according to one of the preceding claims, characterized in that - a mouthpiece blank is provided or formed, in particular by injection molding, with a connecting section defining a longitudinal axis, in particular a hollow cylindrical section, a contact section (4) and a central section (3) located therebetween, and - an air gap (51, 52) is introduced into the mouthpiece blank, in particular by sawing, CNC milling or laser cutting.

14. Inhaler, in particular nebulizer, with a mouthpiece according to one of claims 1-12.

15. Inhaler according to the preceding claim, characterized in that the mouthpiece (1) is interchangeable, in particular pluggable or attached to a connection piece of the inhaler.

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