IMPROVED INHALATION DEVICE

Abstract

The invention relates to the field of inhalation devices for liquids. In particular, the invention relates to a liquid emission mechanism for an inhalation device, as well as a method of emitting a liquid from an inhalation device. The inhalation device comprises a housing (1), a reservoir (2) for storing a liquid, a pumping unit, said unit comprising a riser pipe (5), a hollow cylindrical part (3) having an interior space and being linearly moveable on the riser pipe (5), wherein the pumping chamber is fluidically connected with the reservoir (2), and a nozzle (6) which is connected liquid-tight to an downstream end portion (5B) of the riser pipe (5), and wherein said linear relative motion can be effected by a relative rotation around a rotational axis (R) of a rotatable part (1A) with respect to a counterpart (1B), such that said relative rotation is converted into said linear relative motion by means of a gear mechanism comprising at least one cam surface having a first section (9A) and a second section (9B), and wherein a means for the storage of potential energy (7) is provided. The device is characterized in that said cam surface has, between the first section and the second section (9A, 9B), a third section (9C) of constant height, such that, while said counterpart (1B) slides along said third section (9C), no linear relative motion occurs. A method for the generation of an aerosol comprises, upon rotation of the rotatable part (1B), a first, charging phase for filling the pumping chamber with liquid, and a second, discharging phase for emitting the atomized liquid from the nozzle (6), and is characterized in that between said two phases, a third, resting phase exists during which, despite further rotation, the volume of the pumping chamber remains constant.

Claims

1. Inhalation device for medically active liquids for generation of an aerosol, comprising a housing, inside this housing a reservoir for storing a liquid, a pumping unit, said unit comprising a riser pipe, a hollow cylindrical part having an interior space configured to receive an upstream end portion of said riser pipe, said cylindrical part being linearly moveable on the riser pipe, wherein the cylindrical part and the riser pipe form a pumping chamber having, by means of linear relative motion of the cylindrical part with respect to the riser pipe, a variable volume for generation of a pressure inside said pumping chamber, wherein the pumping chamber is fluidically connected with the reservoir and with a nozzle which is connected liquid-tight to a downstream end portion of the riser pipe, and wherein said linear relative motion can be effected by a relative rotation around a rotational axis of a rotatable part which is part of, or connected to, a first part of the housing with respect to a counterpart which is part of, or connected to, a second part of said housing, such that said relative rotation is converted into said linear relative motion by means of a gear mechanism, said gear mechanism comprising at least one cam surface comprising, in axial direction, a first section of increasing height as well as a second section of decreasing height, the cam surface being capable of sliding along an adjacent counterface, wherein the cam surface is, upon rotation, adapted to slide along said counterface, resulting in said conversion, and wherein a means for the storage of potential energy is provided which is chargeable by means of said relative rotation along the first section, and wherein said energy is releasable to said pumping device when released, and wherein said cam surface comprises, between the first section of increasing height and the second section of decreasing height, a third section of constant height, such that, while said third section of said cam surface slides along the counterface, no linear relative motion of the cylindrical part with respect to the riser pipe occurs, and wherein a dosing cycle which covers the rotation angle of the first, the second, and the third section, corresponds to a rotation of 180 degrees.

2. Inhalation device according to claim 1, wherein the cam surface is arranged at, or connected to, the rotatable part, and the counterpart provides the counterface, or the cam surface is arranged at, or connected to, the counterpart, and the rotatable part provides the counterface.

3. Inhalation device according to claim 1, wherein the counterface is provided by a second cam surface, or a cam, or a roller.

4. Inhalation device according to claim 1, wherein the rotation angle of the third section amounts to 7±6 degrees.

5. Inhalation device according to claim 1, wherein the rotation angle of the first section is selected in the range of from about 165 to about 170 degrees, the rotation angle of the second section is selected in the range of from about 0 to about 2 degrees and the rotation angle of the third section is selected within the range from about 1 to about 13 degrees, wherein the sum of the sectional rotation angles add to 180 degrees.

6. Inhalation device according to claim 1, wherein the cam surface optionally comprises a fourth and/or a fifth section.

7. Inhalation device according to claim 6, wherein the fourth section is a section of decreasing or increasing height between the third section and the second section.

8. Inhalation device according to claim 6, wherein the fifth section is a section of constant height following the second section.

9. Inhalation device according to claim 1, wherein the rotation angle of the second section amounts to 0 degrees, resulting in an axially oriented section of the cam surface.

10. Inhalation device according to claim 1, wherein further a means for blocking the actuation of the inhalation device is present, adapted to inhibit a change of the relative axial position of rotatable part and counterpart corresponding to the third section.

11. Inhalation device according to claim 10, wherein said means for blocking the actuation is adapted to, upon its deactivation, passively allow a further rotation, or actively further rotate the rotatable part such that the second section of the cam surface comes in contact with the counterface, or allow a previously blocked relative axial motion of the rotatable part with respect to the counterpart, corresponding to the second section.

12. Inhalation device according to claim 1, wherein the slope of the first section is selected of the group consisting of being constant, increasing, decreasing, and a combination thereof.

13. Method for the generation of an aerosol by means of an inhalation device according to claim 1, wherein the method comprises, upon rotation of the rotatable part, a first, charging phase for filling the pumping chamber with liquid, and a second, discharging phase for emitting the atomized liquid from the nozzle, wherein between said two phases, a third, resting phase exists during which, despite further rotation, the volume of the pumping chamber remains constant, and wherein one dosing cycle is achieved by a rotation of 180 degrees.

14. Method according to claim 12, wherein the entire resting phase is passed upon a rotation of 7±6 degrees.

Description

DESCRIPTION OF FIGURES

[0088] FIG. 1 shows a schematic simplified cross-sectional view of a generic inhalation device;

[0089] FIG. 2 shows a more detailed cross-sectional view of an inhalation device;

[0090] FIG. 3 shows a simplified developed view of a rotatable part with a cam surface having two series of three sections;

[0091] FIG. 4 shows a simplified top view of the rotatable part having two series of three sections;

[0092] FIGS. 5, 6 and 7 show a schematic simplified developed view of a counterpart with a counterface;

[0093] FIGS. 8, 9 and 10 show different stages of interaction between cam surface and counterface;

[0094] FIGS. 11, 12 and 13 show views of a more detailed embodiment which is in the respective stages that correspond to FIGS. 8, 9 and 10;

[0095] FIGS. 14, 15 and 16 show examples of a fourth section intended to inhibit further rotation of the rotatable part.

[0096] In FIG. 1, a schematic simplified cross-sectional view of a generic inhalation device is shown. FIG. 1 shows the situation prior to first use.

[0097] The inhalation device comprises a housing 1, which is preferably shaped and dimensioned such that it can be held with one hand and can be operated by one finger, e.g. the thumb (not shown). A reservoir 2 for storage of a medically active liquid is located inside the housing 1. The depicted reservoir 2 is designed to be collapsible; that means that during proceeding emptying, the elastic or at least limp walls buckle, so that the underpressure which is necessary for extraction of a certain amount of liquid is not, or almost not, increased. A similar effect can be achieved when a rigid container has a moveable bottom by means of which the interior volume of the reservoir can also be successively be reduced (not shown).

[0098] Further, the inhalation device comprises a pumping device with a hollow cylindrical part 3 forming a pumping chamber of variable volume within the housing 1 for generation of the desired pressure which is necessary for emitting liquid and nebulizing the same. The pumping device can also comprise additional, not depicted components (push button, locking device, etc.).

[0099] Hollow cylindrical part 3 is fluidically connected with reservoir 2 by means of an optional inlet check valve 4. Check valve 4 serves for allowing inflow of liquid into the pumping chamber, and blocks a back flow of liquid into reservoir 2 upon release of a not-depicted blocking means.

[0100] As a means for the storage of potential energy 7, a compression spring is provided which is coupled with one (upwards directed) end to the hollow cylindrical part 3 and which is supported at the bottom of housing 1 (lower part of the figure).

[0101] The inhalation device further comprises a riser pipe 5 with at least one reservoir-facing, upstream end portion 5A which can be received in said hollow cylindrical part 3. In other words, riser pipe 5 can at least partially be pushed into the hollow cylindrical part 3 forming the pumping chamber, resulting in a decrease of the interior volume of the pumping chamber. The term “interior volume” describes that volume which extends from the reservoir-facing inlet of the pumping chamber to the place where the interior end 5A of the riser pipe 5 is located. In the depicted situation, riser pipe 5 is almost entirely extracted from the hollow cylindrical part 3. As a result, the interior volume of the pumping chamber, presently situated between check valve 4 and the upstream end portion 5A of riser pipe 5, is at a maximum, and filled with liquid.

[0102] Preferably, in the section which serves for the reception of the riser pipe 5, hollow cylindrical part 3 has at least a section with a circular inner cross section that corresponds to the (then also) circular outside cross section of the according riser pipe section. Of course, other cross section shapes are possible as well.

[0103] According to the depicted embodiment, check valve 4 is arranged between reservoir 2 and inlet of the pumping chamber.

[0104] Also, the inhalation device comprises a nozzle 6 which is connected liquid-tight to a downstream end portion 5B of riser pipe 5. Nozzle 6 can be any known nozzle which is suitable for nebulizing/atomizing liquid. The nozzle 6 which is depicted as an example uses the principle of nebulization by means of two colliding liquid jets. Preferably, the cross sections of the liquid-containing channels are relatively small, and typically, in the region of microns.

[0105] Also depicted is an optional outlet valve 8 inside riser pipe 5 for avoiding back flow of liquid or air into the downstream end portion 5B of the same from the outside. Outlet valve 8 is arranged in the upstream end portion 5A of riser pipe 5. Liquid can pass outlet valve 8 in direction of nozzle 6, but outlet valve 8 blocks any undesired back flow in the opposite direction.

[0106] As can be seen in FIG. 1, riser pipe 5 is designed immobile and firmly attached to housing 1, indicated by the connection in the region of exterior end 5B with housing 1. Riser pipe 5 is also firmly attached to nozzle 6, which in turn is attached to housing 1 as well. On contrary, hollow cylindrical part 3 is designed to be moveable with respect to housing 1, riser pipe 5, and nozzle 6.

[0107] Not visible in FIG. 1 is the gear mechanism required according to the invention due to which the linear relative motion of the hollow cylindrical part 3 can be effected by a relative rotation around a rotational axis R of a rotatable part which is part of, or connected to, the housing 1 with respect to a second part of said housing 1, such that said relative rotation can be converted into said linear relative motion.

[0108] However, in FIG. 2, an embodiment of the invention is shown where these components are visible. Some of the reference numerals as well as the lower parts shown in FIG. 1 (means for storage of potential energy, reservoir) are omitted. The pumping chamber lies in the overlapping segments of hollow cylindrical part 3 and riser pipe 5, any valves are not shown. In particular, it can be seen how housing 1, rotatable part 1A and counterpart 1B are associated with each other. The counterpart 1B is firmly connected to the housing 1. The rotatable part 1A is partially overlapping with the counterpart 1B. The rotatable part 1A can, within certain limits, linearly move along rotational axis R. However, it does not co-rotate with counterpart 1B. Riser pipe 5 is connected to the part of the housing 1 to which the counterpart 1B is also connected, as well as to the nozzle 6 (not shown), and the hollow cylindrical part 3 is connected to the rotatable part 1A. Thus, by linearly moving rotatable part 1A, the interior volume of hollow cylindrical part 3 which forms a pumping chamber can be changed. In the present example, moving rotatable part 1A upwards (i.e. downstream, or towards the nozzle) reduces the volume, resulting in an emission of liquid, and moving downwards increases it, resulting in (re-)filling the pumping chamber from the reservoir side.

[0109] In FIG. 3, a simplified developed view of the rotatable part 1A having a rim with two series of cam surface sections, each of them comprising sections 9A, 9B and 9C is depicted. The rim provides a downstream surface of rotatable part 1A. Alternatively, the rim with the cam surface could be accommodated in counterpart 1B, or both the rotatable part 1A and the counterpart 1B could feature corresponding cam surfaces. It is clear that all three versions would result in the same translation of a rotation into a linear motion.

[0110] As can be seen in FIG. 3, the first section 9A consists of a rising slope, whereas third section 9C is provided by a “flat” slope. Subsequently, the second section 9B is shaped as a “step” or vertical “drop”. In the depicted example, the corresponding rotation angle for one dosing cycle, i.e. a rotation from the beginning of the first section 9A until the end of the second section 9B, amounts to 180 degrees. A full 360 degree relative rotation of the rotatable part 1A with respect to the second part 1B would thus comprise two dosing cycles.

[0111] FIG. 4 shows the same situation in a top view, i.e. a view parallel to the rotational axis R. Semicircle C indicates the rotation angle of one dosing cycle (180 degrees). At the beginning of said angle (leftmost starting point), the first section 9A begins. The arrow 10 indicates the beginning of third section 9C. Just between this third section 9C and the next first section (thick black line, reference numeral omitted), belonging to a second dosing cycle, lies second section 9B. In the view of the present example, second section 9B runs along the viewing direction (parallel to rotation axis R) and is therefore very short. In contrast, third section 9C has a visible length, such that, upon ongoing rotation, said section is easy to detect manually. If it is intended that the loaded device does not yet discharge a dose, the rotation is stopped anywhere on the third section. When further rotated, the end of third section 9C is reached, and the device is actuated while the counterpart (not shown) glides over the edge of first section 9A and drops along second section 9B. Then, a new cycle can begin.

[0112] FIGS. 5 to 7 show the counterface which is, in the depicted embodiment, a feature of the counterpart 1B. Alternatively, or additionally, it can be a feature of the rotatable part 1A as well. In FIG. 5, the counterface has the inverted shape of the cam surface shown in FIG. 3, carrying all three sections 9A, 9B, 9C.

[0113] In FIG. 6, the counterface is shortened; however, it still has a flat part, which corresponds to third section 9C, as well as a sloping part corresponding to first section 9A. At the right-hand side of FIG. 6, the area drawn in dashed lines indicates the fourth section 9D which “interrupts”, or shortens, the corresponding first section 9A. However, the remaining counterface is sufficient for the desired cam interaction between the two surfaces/components 1A, 1B.

[0114] FIG. 7 shows a short cam 11 which is also sufficient for the desired interaction, but provides a low area of overlap between sections 9A, 9B, 9C (not shown) and its counter face (not shown).

[0115] In FIGS. 8, 9 and 10, different stages of interaction between cam surface and counterface are shown. In this embodiment, both parts 1A, 1B have, for each section 9A, 9B and 9C, matching shapes or slopes of the respective cam surfaces; of course, one has the inverted silhouette of the other. Like parts have like reference numerals (partially omitted). A relative rotation of the actual parts 1A, 1B is depicted by a relative motion in the figures; a relative movement of the counterpart 1B to the right corresponds to the intended rotation direction (loading, resting, discharging).

[0116] In FIG. 8, the loading phase is shown, wherein counterpart 1B glides on first section 9A of rotatable part 1A, resulting in a linear movement of counterpart 1B such as to increase the volume of the pumping chamber (not shown) and load the means for the storage of potential energy (not shown).

[0117] In FIG. 9, the resting phase is depicted, wherein, despite a possible further rotation, no change of volume and loading takes place, since the axially measured distance (or axial position) of parts 1A and 1B remains constant.

[0118] In FIG. 10, said distance decreases rapidly, since counterpart 1B “drops” down along the second section 9B of rotatable part 1A. Thus, this figure depicts the discharging phase.

[0119] Subsequently, the device is at the beginning of another dosing cycle that will start with the loading situation.

[0120] The subsequent drawings FIGS. 11, 12 and 13 correspond to the phases which are schematically depicted in previous FIGS. 8, 9 and 10.

[0121] Note that in the depicted embodiment, a rotation of 180 degrees results in a complete dosing cycle, comprising loading and discharging phase. Further note that, in order to make the relevant regions as well visible as possible, the sectional views do not have identical sectional planes.

[0122] In FIG. 11, the device is in the loading phase. Counterpart 1B is firmly connected to a part of the housing 1. Rotatable part 1A provides the cam surface. In the depicted phase, sloping section 9A is in contact with the adjacent counterface of counterpart 1B.

[0123] In FIG. 12, the resting phase is depicted. In this situation, section 9C (flat section) is in contact with the corresponding counterface. Further rotation around rotational axis R would not (immediately) result in change of the axial position or distance between rotatable part 1A and counterpart 1B.

[0124] In FIG. 13, finally, the discharging phase is shown. In this phase, “dropping” section 9B slides along the corresponding counterface, and the distance between rotatable part 1A and counterpart 1B rapidly decreases, driven by the means for the storage of energy (not shown) which now releases its energy to put the pumping chamber (not shown), putting the same under pressure. As a result, liquid is emitted from the nozzle (both not shown).

[0125] In FIGS. 14, 15 and 16, not-to-scale examples of a fourth section 9D intended to inhibit further rotation of the rotatable part are shown.

[0126] In these embodiments, fourth section 9D is arranged at the end of section 9C. According to FIG. 14, the fourth section 9D is provided with a slope of increasing height. Therefore, when the counterface which is represented by a cam 11 arrives, upon rotation, at the fourth section 9D, climbing said section would require to further charge the means for the storage of potential energy (not shown). However, the user will be able to sense this sudden increase in force needed for further rotation and stop in further rotate. Also, without other external force, the rotation will as well not proceed, making sure that e.g. during storage, no unintentional release of liquid will occur.

[0127] In FIG. 15, the fourth section 9D fulfills the identical function. In this embodiment, it has a shape of a firstly increasing and then decreasing slope (“bump”). Only when the highest point is passed, the emission phase starts.

[0128] In FIG. 16, the fourth section 9D provides a firstly decreasing and then increasing slope (“notch”). When the cam reaches the lowest portion of the fourth section 9D, is rests in this stable position until additional force is provided in order to “lift” it out of said section for the emission to start.

[0129] Compared to an embodiment without a fourth section 9D, such as shown in FIGS. 8-10 which feature a rotational angle of the third section 9C of “original”, full size, the rotational angle of the fourth section covers a percentage from 5% to 50%, or from 10% to 30%, or from 15% to 25%, of said “original” angle, respectively. The maximum height (or depth, respectively) of the fourth section 9D with respect to the third section 9C amounts to a value from 0.05 mm to 5 mm, or from 0.1 mm to 1 mm, or from 0.25 mm to 0.5 mm.

LIST OF REFERENCES

[0130] 1 housing [0131] 1A rotatable part [0132] 1B counterpart [0133] 2 reservoir [0134] 3 hollow cylindrical part [0135] 4 check valve [0136] 5 riser pipe [0137] 5A upstream end portion [0138] 5B downstream end portion [0139] 6 nozzle [0140] 7 means for the storage of potential energy [0141] 8 outlet valve [0142] 9A first section [0143] 9B second section [0144] 9C third section [0145] 9D fourth section [0146] 10 arrow [0147] 11 cam [0148] R rotational axis [0149] C semicircle

[0150] The following list of numbered items are embodiments comprised by the present invention: [0151] 1. Inhalation device for medically active liquids (F) for generation of an aerosol, comprising [0152] a housing (1), inside this housing (1) a reservoir (2) for storing a liquid (F), a pumping unit, said unit comprising a riser pipe (5), a hollow cylindrical part (3) having an interior space configured to receive an upstream end portion (5A) of said riser pipe (5), said cylindrical part (3) being linearly moveable on the riser pipe (5), wherein the cylindrical part (3) and the riser pipe (5) form a pumping chamber having, by means of linear relative motion of the cylindrical part (3) with respect to the riser pipe (5), a variable volume for generation of a pressure inside said pumping chamber, wherein the pumping chamber is fluidically connected with the reservoir (2) and with a nozzle (6) which is connected liquid-tight to an downstream end portion (5B) of the riser pipe (5), [0153] and wherein said linear relative motion can be effected by a relative rotation around a rotational axis (R) of a rotatable part (1A) which is part of, or connected to, a first part of the housing (1) with respect to a counterpart (1B) which is part of, or connected to, a second part of said housing (1), such that said relative rotation is converted into said linear relative motion by means of a gear mechanism, said gear mechanism comprising at least one cam surface having, in axial direction, a first section (9A) of increasing height as well as a second section (9B) of decreasing height, the cam surface being capable of sliding along an adjacent counterface, wherein the cam surface is, upon rotation, adapted to slide along said counterface, resulting in said conversion, [0154] and wherein a means for the storage of potential energy (7) is provided which is chargeable by means of said relative rotation along the first section (9A), and wherein said energy is releasable to said pumping device when released, [0155] characterized in that said cam surface has, between the first section of increasing height (9A) and the second section of decreasing height (9B), a third section (9C) of constant height, such that, while said third section (9C) of said cam surface slides along the counterface, no linear relative motion occurs. [0156] 2. Inhalation device according to item 1, wherein [0157] the cam surface is arranged at, or connected to, the rotatable part (1A), and the counterpart (1B) provides the counterface, or [0158] the cam surface is arranged at, or connected to, the counterpart (1B), and the rotatable part (1A) provides the counterface. [0159] 3. Inhalation device according to item 1 or 2, wherein the counterface is provided by a second cam surface, or a cam (11), or a roller. [0160] 4. Inhalation device according to any of items 1 to 3, wherein a dosing cycle which covers the rotation angle of the first, the second, and the third section (9A, 9B, 9C), corresponds to a rotation of 360 degrees, or to a whole-number fraction thereof. [0161] 5. Inhalation device according to item 4, wherein the sum of the rotation angles as defined in claim 4 amounts to 180 degrees. [0162] 6. Inhalation device according to item 5, wherein the rotation angle of the third section (9C) amounts to 7±6 degrees. [0163] 7. Inhalation device according to any of the preceding items, wherein the rotation angle of the second section (9B) amounts to 0 degrees, resulting in an axially oriented section of the cam surface. [0164] 8. Inhalation device according to any of the preceding items, wherein further a means for blocking the actuation of the inhalation device is present, adapted to inhibit a change of the relative axial position of rotatable part (1A) and counterpart (1B) corresponding to the third section (9C). [0165] 9. Inhalation device according to item 8, wherein said means for blocking the actuation is adapted to, upon its deactivation, [0166] passively allow a further rotation, or actively further rotate the rotatable part (1A) such that the second section (9B) of the cam surface comes in contact with the counterface, or [0167] allow a previously blocked relative axial motion of the rotatable part (1A) with respect to the counterpart (1B), corresponding to the second section (9B). [0168] 10. Inhalation device according to any of the preceding items, wherein the slope of the first section (9A) is selected of the group consisting of being constant, increasing, decreasing, and a combination thereof. [0169] 11. Method for the generation of an aerosol by means of an inhalation device according to any of the preceding items, wherein the method comprises, upon rotation of the rotatable part (1A), a first, charging phase for filling the pumping chamber with liquid, and a second, discharging phase for emitting the atomized liquid from the nozzle (6), characterized in that between said two phases, a third, resting phase exists during which, despite further rotation, the volume of the pumping chamber remains constant. [0170] 12. Method according to item 11, wherein one dosing cycle is achieved by a rotation of 180 degrees. [0171] 13. Method according to item 11 or 12, wherein the entire resting phase is passed upon a rotation of 7±6 degrees.