WO2015080653A1

WO2015080653A1 - Inhalation device for powdery substances

Info

Publication number: WO2015080653A1
Application number: PCT/SE2014/051398
Authority: WO
Inventors: Yutaka Kataoka; Jan HEDEGAARD BROCH; Jan ÅBERG; Stefan FRANSSON; Ulf RYTTERHOLM
Original assignee: Simplified Solutions Sweden Ab
Priority date: 2013-11-26
Filing date: 2014-11-25
Publication date: 2015-06-04
Also published as: SE537715C2; SE1330151A1

Abstract

The invention relates to a multi-dose inhaler for substances in powder form, for example comprising at least one dosring (2) with a plurality of preferably circular arranged powder chambers (1) intended for the respective dose of powdered substance, and a feed mechanism (5) that is arranged to feed the dose-ring (2) or dose-rings (2) in the intended direction of movement, with at least one seal (11,22) provided to seal the powder chambers (1) from each other and from the environment for retaining the doses of powder in each powder chamber (1). The invention is achieved by letting the advancing mechanism (5) be arranged to feed the dose-ring (2) or dose-rings (2) so that at least two powder chambers (1) at a time are moved to a position of delivery of the doses of powder, to an air channel (7) comprising at least a section (7a, b) that is arranged in the position of the powder chamber (1) that have been advanced, that the air channel (7) or its section (7a, b) is arranged to allow at least two powder chambers (1) to be opened for inhalation, substantially at the same time, in the air channel (7) so that the powder chambers (1) and their powder doses are exposed to the air channel (7) through which the powder doses are allowed to pass out through the air channel (7) and mixed with each other by means of the airflow.

Description

INHALATION DEVICE FOR POWDERY SUBSTANCES

TECHNICAL AREA

The present invention relates generally to multi-dose inhalation devices for powdery substances. Specifically it refers to a so-called multi-dose-inhaler (DPI, Dry Powder Inhaler) that is powered by the user's own respirational ability. Multi-dose-inhalers are intended to alleviate illnesses caused by asthma and other ailments that prevent normal respiration.

TECHNOLOGY BACKGROUND

On the market today, there are a number of inhalers for powdery substances, most of which are so-called multi-dose - inhalers. In recent years, research and clinical studies have shown that treatment with two active ingredients at the same time can provide a significant better effect than to just use one, which has historically been the dominant treatment method. LAMA / LABA treatments require an inhaler that can hold the doses of the various active substances separated until the user inhales. Hence, the doses cannot be mixed with each other inside of the inhaler; they can only mix at the moment of inhalation i.e. when the patient inhales. Few inhalers today can store the doses separated and then deliver them both at inhalation. Furthermore, the ones currently marketed today, whether they deliver one active ingredient or two, are relatively large and bulky in their design, which means that the storage of the inhaler in clothes / -purses and the handling of the inhalers, are not user friendly. Another problem is that they do not always deliver a precise dose and the intended dose and that unintended forwarding of s new dose is possible i.e. the user may mistakenly inhale a double dose. When the dose is in the position for inhalation the user can accidentally blow air into the multi-dose inhaler, so that moisture can accumulate and cause the powdered substance to stick together. Furthermore known multidose inhalers consist of many parts, which makes them difficult and expensive to produce and thus expensive to buy for the end user. A larger number of parts also increases the number of error sources. In principle, at a given quality level, the number of errors increases linearly with the number of parts. This innovation solves the above described problems concerning the operation and the number of parts, while providing the ability to store two active ingredients in the inhaler separated to then deliver them both at once so they get mixed up only when they enter the body of the patient.

Multidose inhalers on the market as well known patented variants such as

US6273085, US7275538B2, US6871647, US7395821 B2 and US2009205657A1 , consists of at least nine or more parts and some form of sealed encapsulation of the powdery substance to be inhaled. To expose the powdered substance an enclosure must be mechanically penetrated, a seal lifted, rolled up, torn off or the like, to provide access to the powdered substance. This encapsulation or rather the mechanism needed to break the seal is the single most critical factor in reducing the number of individual parts and also to reduce the size of the multi-dose inhaler.

These problems are solved by the present invention. None of these designs are anticipated to store two different types of active substances and then deliver the same inhalation.

US6273085 discloses an inhaler with a separate cassette for the powder. The cassette consists of a disc that has axial holes that constitute the powder chambers. On the top and at the bottom there is a seal that encloses the holes in the disc, and thus seals the powder chamber. The sealing pressure is provided by an upper and lower spring washer. Thus, five parts are used just to enclose the powder chambers. In the present invention, two parts provide the same function, dose ring and the upper housing. An upper housing part is available in both solutions. In the present invention an upper housing part constitutes one of the two parts to enclose the powder chamber. With that logic, the present invention has one part compared to the known patent's five. The fewer parts mean lower manufacturing cost, lower assembly costs and fewer errors. US7275538B2 discloses an inhalator with a powder chamber in the form of a cylinder, which is located after each other in a disk and that uses a piercing device with a needle that penetrates one chamber at a time to expose said chamber and hence, make it possible to inhale its content. Each chamber is fed forward, one at a time, after which it is penetrated from the inner part of the disk. The penetrating device means that the overall height is about 1 1 times as high as the height of the air channel. On the needle that penetrates both chambers medicament can fasten the powder can also end up in the aerodynamic shadow under or behind parts of the film that is folded inward in the powder chamber at penetration, furthermore, the foil can contaminate the powder. The solution also complicates the production because the chambers have to be filled with medication and then sealed on both the internal and the external side of the disk. The number of parts is at least nine. I US6871647 describes a device consisting of three times as many parts as the present invention. To expose the dose to be inhaled from the chambers a covering encapsulation / tape is "lifted" up or "peeled" off. This complicated way of opening the chambers also risks that parts of the covering encapsulation can be mixed with the substance in the powder chamber and thus contaminate it. Judging by the figures and the elements described in the document, the inhaler is considerably thicker and in every way larger in size and thus more bulky in its design than the present invention and therefore more cumbersome to store and handle.

I US7395821 B2 describes a device consisting of twelve parts where the tape that is mounted on the chambers with the medicament, is to be penetrated and then inhaled through the "needle" used for penetration. Hence there is a risk of contaminating the substance to be inhaled and the powdered substance in the powder chamber can also fall into an "aerodynamic shadow" i.e. preventing all of the available dose to be inhaled due to the fact that powder may stick to the needle that penetrated the chamber, and end up outside the same needle upon inhalation. The feeding of the doses and the handling at inhalation also requires that two hands must be used when the inhaler is handled, as the top and bottom need to rotate in opposite directions for a new dose to be fed and a "button" has to be pressed in order to penetrate the covering seal under which the substance to be inhaled is placed. Judging by the figures and the elements described the inhaler is considerably thicker and in every way larger in size and thus more bulky in design, than the present invention and therefore more cumbersome to store and handle.

US2009205657A1 describes a device that includes twice as many parts as the present invention, and where the covering sheath over the powder chambers must be removed, penetrated, drawn apart (blisters), etc., for the user to be able to inhale the substance in powder form. The structure thus uses a completely different sealing solution than the present invention, with the above-described risk of contamination as a result. The described sealing solutions also mean that space is used for the opening mechanism needed to expose the powder to be inhaled. That in turn means that the size of the multi-dose inhaler will inevitably be larger than the present invention, due to the method of exposing the powdery substance eliminates the need for such a mechanism. Judging by the figures and the elements described this known inhaler is considerably thicker and larger in size and thus more bulky in design than our innovation and therefore more cumbersome to store and handle.

SUMMARY OF THE INVENTION

The multidose inhaler according to the invention consists of a dose-ring containing powder chambers in the form of indentations or recesses in said dose-ring, oriented in a circle. Every other powder-chamber of the dose-ring is preloaded with one first active substance while every other contains a second active substance. The dose- ring abuts a sealing material which is disposed directly adjacent to said indentations / powder chamber. In the seal is arranged at least one opening element having a surface preferably sized to three quarters of each powder chambers' upwardly open area. The opening elements are cut or punched to form an openable element in the seal. One edge of the sliding element is not intersected but form a kind of "hinge" in the seal. No material has been removed, which means that the opening element fits exactly into the surrounding sealing material and which means that the powdery substance cannot pass through the movable element or through the slot. The seal may e.g. glued or fastened to dose ring through recesses between the powder chambers in which the corresponding increases in the sealing ring, fits. Only on one of the longer sides of the powder chamber, the seal is attached in the dose-ring. The inhaler housing presses against seal of the powder chambers, thus helping to keep the seal in place. The casing can preferably be provided with a local raised section of the air channel, where the sealing function between the housing, seal and dose-ring ceases. When the protective cap of the nozzle, which also functions as the feeding mechanism, opens, the dose ring is rotated forward one step and at least two powder chambers are fed thereby to the air channel and exposed to the air flow that occurs when an inhalation is made. The two fed powder chambers contain the two different active substances. The air channel is designed so that a negative pressure, preferably a venturi effect occurs in the region of the powder chambers. A restrictor is preferably provided downstream said powder chambers which shall deliver the doses. This constriction causes a speed increase of the air stream. After compressing the air channel widens gradually giving a local under pressure. The widening is located in the area of the powder chambers which shall deliver the doses. The vacuum lifts the opening element and the air flowing past the chambers pulls the powder from each chamber, respectively. Alternatively, you can arrange an openable element for each powder chamber, where they are opened simultaneously for the delivery of the powder doses. Upon inhalation, the inhaler works as described above, i.e. that the created under pressure opens the openable element or elements covering the two mounted powder chambers containing the two different active substances, which then are entrained by the air stream. The purpose of the invention is to create an as thin and as functional, multi-dose inhaler, as possible which can simultaneously deliver at least two different active substances at every inhalation. The goal is to simultaneously reduce the overall height of the multi-dose inhaler so it can be conveniently stored for example in a breast pocket. Length and width is reduced to approximately credit card size which means that the multi-dose inhaler is significantly smaller than what is normal among known multi-dose inhalers and thickness only approximately one third of the same. The reduced height is an important advantage for the user. It is accomplished by that the geometrical shape is arranged so that the overall height is approximately the sum of the thicknesses of the material of the lower housing together with the thickness of the material of the dose— ring, the height of the powder chamber together with the thickness of the upper housing. This building height applies over the vast majority of the inhaler top surface. This geometric shape provides beneficial effect in that it allows for a considerably lower height than the known inhalers. A further object of the invention is to design inhaler with as few parts as possible to facilitate the production and thus making the inhaler more cost-effective to produce, which gives the end user a much cheaper option of a multidose inhaler than what are available in the market today. The parts are mainly; an upper and a lower housing part that encloses the dose-ring, the seal that is directly adjacent to the powder chambers and the indexing mechanism. Altogether, five parts. With the help of the few parts and the specific structure the multidose-inhaler is straightforward and cost effective to manufacture. Automation of production can be conducted using standardized picking robots because all components have the same mounting orientation. The openings in the seal that lies against the powder chambers can be punched out of the seal by the meter. Thus, no need for manual operations used in the manufacture. The seal may, alternatively, double-injection molded onto dose-ring instead of being stamped out by the meter. In this case, seal assembly process is taken out of the assembly process; it is instead performed in the molding process. In that case, the punching out of the opening elements are taken out of the assembly process since it is not possible to integrate that in a process of double injection molding. The openable elements are an advantage in terms of protecting the dose if a user unintentionally blows into the inhaler immediately before the breathing in. However, most inhalers do not have a protection of the dose if the user accidentally blows into the inhaler, all the rest, for inhaler central functions, are intact even with the double injection molded solution. The sealing pressure is accomplished in the same manner for a seal stamped from the meter with opening elements on a dose-ring via a double molded seal. The sealing pressure is achieved by the upper and lower casing enclosing dose-ring being clipsade, screwed or welded together to push axially towards said dose-ring. The seal may alternatively be separately molded instead of double injection molding. The seal may alternatively be secured to a housing part that abuts the side of dose- ring where the powder chambers are located.

Another object of the invention is that the handling of the multidose inhaler should be as easy and user friendly as possible while possible misuse is obviated. You can take it from, for example, a breast pocket, put your thumb on the feeding mechanism, feed the two doses, inhale, then close it again and put it back in his breast pocket, all in one manual and continuous motion. The design thus means that the user can manage the multi-dose inhaler using only one hand while, regardless of how the user is holding it, it is ensured that the dose inhaled in its entirety. The device also eliminates the risk of accidentally inhale a twice as large a dose as intended, or more, at the completion of the feeding operation and inhalation. After all of the doses are consumed, the multidose inhaler is discarded. A unique feature is achieved by opening the powder chamber through letting the enclosing sealing effect made by the housing, cease at the air channel over said powder chambers and to let the under-pressure created by the air stream lift at least one openable element of the seal that cover the powder chambers The chambers are hence emptied by the air stream. The seal is attached at only one side of the powder chambers. At each feeding the dose-ring exposes two powder chambers at a time from its sealed containment by letting the seal on the dose-ring slide against the upper housing. The powder chambers are transported in this manner in the rotational direction towards the air channel, to be exposed with only the prepared openable elements of the seal, covering said chamber, when the feeding is complete. The solution eliminates the need for devices to puncture a foil, tear up a foil, mechanically lift a rubber seal or mechanically lift a sealing lid. Since the unraveling of the powder chamber is performed in this unique way, the building height and number of parts are reduced to a minimum while maintaining safety and good usability. Each chamber is separated under the covering upper housing until fed forward for inhalation. This means that the two active substances cannot possibly be mixed. The design also eliminates the risk of contamination of the powder which a known puncturing device may cause and that portions of the substance ends up in the aerodynamic shadow by parts of the perforated enclosing foil. The multidose inhaler could in an alternative arrangement be provided with two separate air channels which are constructed as described above, each air channel thus leads a stream of air over each fed forward powder chamber. They have both the previously described throttle just before the powder chamber to produce the under-pressure required to open or openable elements. One air duct thus leads up to one of the fed powder chambers and the other leads to the second fed powder chamber. The air channels may alternatively be separated from each other all the way to the nozzle so that it is first in the mouth / trachea that the two active

substances get mixed.

In an alternative embodiment, an inventive dose-ring could be provided with powder chambers arranged in the surface where the powder chambers are arranged in at least two substantially circular rows, an outer and an inner, or in a spiral form, where each powder chamber is placed at a gradually changing distance from the center of the dose-ring At each feeding two new doses are placed at the place of delivery. One active ingredient is in the inner row of powder chamber and the other in the outer row. Both are emptied at the same time at inhalation. In this way at least two rows of powder chambers are oriented in the dose-ring using only one further detail. 60 or more doses can hence be fitted and the inhaler will consist of 6 instead of 5 parts but this is still considerably less than the approximately 13 pieces and stripes with powder chambers that the leading competitors use. The present invention may also include more than two rows of powder chambers. However, such an inhaler have to be bigger than the present invention because the diameter of the dose-ring must accommodate, for example, four rows of chambers and thus one of the purposes of the invention is waived.

Two dose-rings can also be mounted on or adjacent to each other with separate powder chambers in each ring. In such a solution they are located, just opposite or above one another so that the two chambers are placed in position for delivery at the same time, at each feeding. The thickness of the inhaler will in such a solution increase but the total number of parts, and its thickness is nevertheless still kept at a lower level than the inhalers that are currently on the market. The described multi-dose inhaler is substantially smaller and most of all thinner than the known multi-dose inhalers. It combines a small number of parts and an easier and safer handling at the same time being able to deliver at least two different active ingredients at each inhalation. The construction also ensures that the two active substances are, before inhalation, separated in their respective chambers. The inhaler will also, with the proposed design, be simple and thus inexpensive to manufacture.

The above mentioned and more purposes and benefits are achieved by the invention using a multidose inhaler in accordance with, in the characteristic part of the patent claim 1 specified features. BRIEF LIST OF DRAWINGS

The invention is described in more detail below in a few preferred design examples with use of the attached drawings.

Figure 1A and 1 B displays and inventive multidose inhaler in an exploded view. Figure 2A and cross section 2B displays the inlet throttling of an inventive- inhaler and that the area expansion over the powder chambers creates a negative pressure (venturi effect) that opens the openable element and pulls the powder out of its respective chamber.

Figure 2C and 2D displays how one openable element per chamber can be arranged as well as arranging one for the two fed powder chambers.

Figure 3A displays an inventive multi-dose inhaler with two parallel spaced powder chambers and Figure 3B displays how two serially powder chambers can be arranged and fed to the air channel and the air stream carrying substances in powder form simultaneously from the respective chambers. Figure 4A and cross section 4B displays yet another alternative solution as to how the powder chambers can be arranged to be fed forward at least two at a time and how the air stream delivers the substances in powder form out of the respective chambers at the same time.

Figure 5A and cross section 5B displays another alternatives solution as to how the powder chambers can be arranged to be fed forward at least two at a time and how the air stream delivers the substances in powder form out of the respective chambers at the same time.

Figure 6A and cross section 6B displays yet another alternative solution as to how the powder chambers can be arranged to be fed forward at least two at a time and how the air stream delivers the substances in powder form out of the respective chambers at the same time.

Figure 7A and cross section 7B displays yet another alternative solution as to how the powder chambers can be arranged to be fed forward at least two at a time and how the air stream delivers the substances in powder form out of the respective chambers at the same time.

Figure 8A, B, C and D displays more alternative methods as to how the powder chambers can be arranged to be fed forward at least two at a time. Figure 9 displays an alternative way to place the sealing of the powder chambers.

Figure 10A and 10B displays an inventive multidose-inhaler where the feeding of the powder chambers is performed during the first half of the opening sequence and how the feeding is connected to the opening mechanism.

DESCRIPTION OF PREFERRED EMBODIMENTS

Figure 1 A displays an inventive multi-dose inhaler comprising a number of powder chambers 1 that are arranged in a dose-ring 2 and oriented in a circular shape each chamber containing a pre-loaded amount of substance in powder form. The dose- ring 2 is in turn arranged between an upper housing 3 that is rotationally fixed and a lower hosing 4 which is also rotationally fixed. The powder chambers 1 have their openings oriented towards the upper rotational fixed housing 3. The multidose- inhaler is provided with a feeding mechanism 5 that includes a covering cap which, while opening up for the mouth piece 6 also feeds the dose-ring 2 at least two powder chambers 1 at a time to a position for inhalation in the air channel 7. In the lower rotational fixed housing part 4, there is an air inlet 8 arranged for the air channel 7. The air inlet 8 consists of one or more inlet holes 9. Downstream said air holes 9, after the inlet 8, a spiral 10 is designed with the aim to, as an extra precaution, catch powder that could fall out of any of the powder chambers if for example the user shakes the inhaler and / or if it is kept in vertical position after a feeding. This construction ensures that the powder is trapped before it passes out through the inlet holes 9. The solution means that the substance is certain to be inhaled as a whole no matter how multidose inhaler is oriented or managed by the user at time of inhalation.

A seal 11 is provided with pre-punched openable elements 12 where the seal 11 may be arranged against dose-ring 2 where the openable elements are aligned with the powder chambers 1 in the dose-ring 2 second. The material of the seal 11 may conveniently, but not necessarily, be EPDM (ethylene propylene diene monomer), which can be injection molded in very thin layers. The openable elements may also cover two powder chambers (not shown) as well as one opening element for each chamber. The figure also displays that the feed mechanism 5 consists of a feeding arm 14 with cogs 13. When opening the inhaler the feeding arm 14 interacts, through the cogs 13 with the cogs 15 on the dose-ring so that the next powder chamber 1 is fed to the section 7a of the air channel which is aligned transverse to the direction of rotation of the dose-ring 2. The internal length and width of section 7a of the air channel is preferably slightly greater than the opening area of at least two powder chambers 1 , or in any case substantially covers the opening area of at least two powder chambers, to ensure that the entire opening area of the powder chambers 1 are exposed to section 7a of the air channel. It is also conceivable that the section 7a of the air channel is enclosed in the material of the upper housing 3 thus removing the need for an elevation in the upper housing 3 to be made which extend beyond the main outer surface of said upper housing 3.

At section 7a of the air channel the fed powder chambers are hence exposed and only the seal 11 with the prepared openable element 12 covers, in this position, the powder chambers 1. Thus, when feeding, at least two powder chambers are fed from their closed position against the upper housing 3 to be exposed in section 7a of the air channel.

After inhalation, when the user closes the feeding mechanism 5, the feeding arm 14 springs away from the cogs 15 on the dose-ring 2 on its way back to its starting position. Backstops 16 that are integrated into the dose-ring 2, prevents the dose- ring 2 from rotating backwards by letting them engage the cogs 17, which are integrated in the lower housing 4. The cogs 15 in the dose-ring together the with backstops 16 and the cogs 17 integrated in the lower housing, ensures that only one set of powder chambers 1 at a time can be fed into position for inhalation. The backstops 16 are arranged to spring back somewhat so that they can, when feeding the dose-ring forward, spring up over the cogs 17 that are integrated in the lower housing 4. This solution means that only one set of powder chambers at a time can be placed in position at section 7a of the air channel.

Figure 1 A also displays that there is, in the lower housing 4, a circularly shaped border wall 18 which keeps the dose-ring 2 in position. In the lower housing 4 there is also a guide hole 19 for the advancing mechanism 5. At assembly, the inhalers lower housing 4 is first placed in a fixture (not shown). The dose-ring 2 and the feeding mechanism 5 are then placed in this section. Thereafter the filling the powdery substance is filled into the powder chambers. The seal 11 on the dose-ring is then set against the second dose-ring. As the last step the multi-dose inhaler is sealed with the use of the upper housing 3. Figure 1 B displays the lower side of the upper housing 3.

Figure 2A and 2B displays how section 7a of the air channel, seen in the air flow direction, is provided with a throttle 20 which means that, at inhalation the air speed increases in the area just before the fed powder chambers. In the area above the powder chambers 1 , in section 7a of the air channel, the air channel gradually widens resulting in an under-pressure being created that lifts the openable element 12 in the seal 11 and how the air flowing past pulls the powder from the powder chambers 1. The local under pressure created by the throttle 20, is caused by a so-called venturi effect. The seal 11 prepared openable element 12 is like a flap or a hatch. The powder is thus exposed to the air stream 21 and drawn out of the inhaler together with the inhaled air and down into the user's throat. In this example, the openable element 12 in the seal 11 covers both of the fed powder chambers 1. The openable element can alternatively be provided in the seal 11 so that the fed chambers are covered by one openable element each. Alternatively, the openable element may also be attached only at section 7a of the air channel (which is displayed in

Figure 2A). In the latter case, thus the same openable element is used for all of the powder chambers 1 that are fed to section 7a of the air channel. The dose-ring 2 can hence be provided with a number of openable elements 12 corresponding to half the powder chambers 1 in in the dose-ring 2.

Figure 2B displays a cross section through both the top and bottom housing and through the intermediate dosring 2 and seal 11 and displays section 7a of the air channel and the powder chambers 1 exposed therein. In the figure it is made clear how the openable element 12, which covers the two fed powder chambers, open at the same time as the air flows past and how the powder is released from the respective powder chambers. Figure 2C and Figure 2D displays that an openable element 12 per powder chamber 1 can be provided, as well as a flap that covers two chambers, as shown in Figure 2A and 2B. Both flaps can be caused to open by the under-pressure created by said venturi effect, when the chambers have been fed to section 7a of the air channel.

Figure 3A with cross section 3B displays an alternative embodiment of the seal and the powder chambers 1 that feeds them at least two at a time. In this example the powder chambers 1 are side by side of each other as previously described. At each feeding the chambers are placed at least two at a time in section 7a of the air channel at every single feeding. The seal 11 is in this example arranged directly in the housing immediately above the powder chambers. Figure 4A with the cross section 4B displays an alternative embodiment of the powder chambers 1 to feed them at least two at a time. In this example they are in line with each other seen from the center of the inhaler towards the periphery. At each feeding at least two chambers are fed to section 7a of the air channel at every single feeding. Section 7a of the air channel is slightly longer in this example than previously described, so that the two chambers can be exposed simultaneously in said section. Otherwise, the inhaler is identical in design and size. The seal 11 is in this example arranged directly in the housing immediately above the powder chambers. One can also imagine an openable element as described previously. However, that example is not displayed in this figure. Figure 5A with the cross section 5B displays an alternative embodiment of placement of the powder chambers 1 , to be able to feed them at least two at a time. In this example, two dose-rings 2 are placed next to each other, but at a certain distance from each other. Powder chambers are located on top of each other with their respective opening directed towards the upper housing 3. At each feeding both powder chambers are placed in section 7a of the air channel. The powder chambers must be positioned exactly on top of each other and hence, the dose-rings must be identical in size for both powder chambers, one in each dosring 1 , to be

simultaneously fed to the position of delivery. The inhaler is in this case slightly thicker than if, as previously described; only one dosring 1 is used where two powder chambers are simultaneously advanced before each inhalation. The advantage is that in this way, more doses will fit in the inhaler without having to change the outer boundaries of the same. The thickness of the inhaler will however increase, slightly. The seal 11 is in this example arranged directly in the parts immediately above the powder chambers. One can imagine an openable element covering each powder chamber as previously described. However, this is not displayed in figure 5A and 5B. As with the section 7a of the air channel, the upper dose-ring 2 can also be constructed with a slightly sloping underside, at least at the area of the respective dose chambers 1 , so that section 7a of the air channel forms a gradually increasing cross sectional area in the direction of air flow, to achieve the venturi effect and therefore a more efficient discharge of the powder. Figure 6A with the section 6B displays an alternative embodiment of the placement of the powder chambers 1 , to feed them at least two at a time. Also in this example have two dose-rings 2 that are placed next to or on top of one another. The dose- rings 2 are in this example placed facing one another but arranged at a certain distance from each other so that an air channel 7 is formed in between the dose- rings. At each feeding two chambers are positioned in section 7a of the air channel which, in this example, is incorporated within the inhaler rather than being positioned on the outside as shown in Figure 1. The powder chambers must also in this example be positioned exactly on top of one another and hence the dose-rings have to be of identical size, to enable both of the powder chambers; one in each dosring 2, to be simultaneously fed to the position of inhalation. The size of the inhaler becomes identical to the options explained in Figure 3 with the difference that section 7a of the air channel is not entirely contained in the inhaler. The seal 11 is in this example arranged directly in the parts immediately above the powder chambers. One can imagine an openable element covering each powder chamber as previously described. However, this is not displayed in figure 6A and 6B.

The seal 11 is thus provided with an opening to form the air channel 7 and the edges of the seal sides can be formed with slanted surfaces so that the air channel 7 is given a larger area downstream than upstream the powder chambers. Hereby a gradually increasing cross-sectional area in the direction of airflow is created with the technical effect that a venturi effect and thus a more efficient exhaust / extraction of the powder is obtained. Figure 7A with cross section 7B shows an alternative embodiment of placement of the powder chambers 1 , to feed them at least two at a time. In this example, a dose- ring 2 is displayed where the powder chambers 1 are arranged directly opposite one another on either side of the same. At each feeding both powder chambers are positioned in the sections 7a and 7b of the air channel which in this example consists of a protrusions on both sides of dose-ring so that the fed powder chambers are freed from their respective enclosures between the upper and lower 3, 4 housing on the corresponding sides of dose-ring 2. The thickness of the inhaler will probably be slightly larger than that described in the Figure 1 because of the dose-ring in this example, needs to enclose two powder chambers located opposite one another. The seal 11 is in this example arranged directly in the part immediately above the powder chambers. One can imagine an openable element covering each powder chamber as previously described. However, this is not displayed in figure 7A and 7B.

Figure 8A, B, C and D displays further embodiments of how the powder chambers can be arranged to be fed at least two at a time. The dose-rings previously described are not the only way to arrange powder chambers to feed at least two at a time.

Thus, the hitherto exemplary ways to position powder chambers 1 does not necessarily need to be in a dosring 2. They may be located on a strip (like a blister pack) as displayed in Figure 8C, a ring such as displayed in Figure 8A or in a continuous line as displayed in 8D . Figure 8B displays a dosring where the chambers are positioned outside or inside each other as previously described in

Figure 4A and B.

Figure 9 displays an alternative way to place the seal 22. Instead of, as in Figure 1 , having a separate seal with openable elements, the seal can be positioned for example on the underside of the upper housing 3. The seal 22 for the substance in the powder chambers 1 is in this example arranged in a fixatedly fashion vertically and positioned on the contact area between dose-ring 2 and the upper housing 3. The seal 22 can, in the same way, hence, be added to the lower housing 4, for example in the way displayed in Figure 7, where the dose-ring has powder chambers 1 on both sides of said dose-ring.. This type of seal 22 can preferably be achieved by double injection molding and given a soft finish. In this example it openable elements are not used, instead the dose-ring 2 slides, at each feeding, against the seal 22 arranged at the contact surface. Alternatively, the seal can also be injection molded in dose-ring(s) holding the powder chambers, hence directly integrating the seal in said dose-ring. This option is however not displayed in Figure 9.

Figure 10A and 10B displays how a multidose inhaler, with one or more dose-rings, is opened and how, when this is action is performed, said dose-rings are fed forward one step at a time and how the mouth piece 6 is exposed by the, in feeding arm 14, integrated feeding mechanism 5.

The description above is primarily intended to facilitate the understanding of the invention, and is of course not limited to the presented embodiments, also other embodiments of the invention are possible and conceivable within the framework of the innovative thought and the subsequent claims and scope of protection, thus, it is conceivable that instead of a circular dosring use powder chamber arranged in a straight line, such as in the form of a belt, a roller or the like. !

Claims

1. A multi-dose inhaler (2) , comprising a plurality of substantially circular recesses or powder chambers (1), for storing a respective dose of a preloaded powdery substance,

J - that a forward mechanism (5) is arrangedjo feed the dose-ring (2) in its direction of rotation,,

- that at least one seal (11 ,22) is arranged to seal the powder chambers (1 ) from each other for retaining the doses of powder in the respective powder chamber (1 ), characterized in

- that a forwards mechanism (5) is is arranged to feed the dose-ring (2) so that at least two powder chambers at a time are positioned side by side, seen in the rotational direction of the of the dose-ring, to a position where doses of powder can be released,

- that an air channel ( 7) comprising at least one section ( 7a, b) that is arranged in the position of the advanced powder chambers (1 )

- that the air channel (7 ) or its parts ( 7a, b ) are arranged so that its / their internal length and width substantially covers at least two powder chambers (1 ) opening area to ensure that they may be fully exposed to the air channel ( 7) or the parts (7a, b) of said air channel (7) and for the flow of air that flows therein at inhalation ,

- the air channel (7) or its air parts (7a, b) are arranged to so to admit that at least two powder chambers (1), at inhalation are opened substantially simultaneously towards the air channel (7), due to the negative pressure created by the air flow, so that the powder chambers (1) and their powder doses are exposed to the air channel (7) through which the doses of powder are allowed to flow out, through the air channel (7) and be mixed with each other by means of the airflow,

- the seal (11) is provided with at least one openable element (12) which is, or are arranged to substantially simultaneously open and expose at least two powder chamber (1 ) at a time to the air channel (7) in the position for dispensing the powder doses whereby the doses may flow out through the air channel (7).

2. A multidose inhaler according to claim 1 ,

characterized in

- that section (7a, b) of the air channel is provided with a gradually increasing cross- section seen in the direction of the air flow, i.e. so that the cross sectional area upstream of a first region is narrower than the cross sectional area downstream in a second region, so that a negative pressure, or a so-called venturi effect, occurs in the region of the openable elements (12) and contributes to open this / these openable element(s).

3. A multidose inhaler according to claim 1 ,

characterized in

- that the seal (11 ) is arranged to be moved with the dose ring (2) and that it is provided with a number of openable elements (12) corresponding to half the number powder chambers (1 ) in the dose-ring (2).

4 A multidose inhaler according to claim 1 ,

characterized in

- that section (7a, b) of the air channel, in the area of the dose-ring (2) with the powder chamber (1 ) and the openable element (12) is provided with a restrictor (20) or a gradually increasing cross-sectional area, seen in the direction of the air flow, i.e. so that the cross sectional area in a the first region is smaller than the cross sectional area in a second region, so that a vacuum or a so-called venturi effect occurs in the area of, at this location, exposed movable elements (12) which contributes to open this / these elements.

5. A multidose inhaler according to any of the previous claims,

characterized in

- that the width and the length of section (7a, b) of the air channel at the rotational position for delivery of the dose of powder, is arranged to cover at least the surface of the only or several, at this position, exposed openable elements (12).

6. .A multidose inhaler according to any of the previous claims,

characterized in

- that the seal (1 1 ) at the area of the air channel (7) is provided with oblique side edges in order to achieve a gradually increasing cross sectional area in the direction of the air flow, with the technical effect that a venturi effect and hence an efficient exhaust/suction of powder is achieved.

7. .A multidose inhaler according to any of the previous claims,

characterized in

That the dose-rings are arranged adjacent to each other but at some distance from one another.