WO1998011929A1

WO1998011929A1 - Powder dispenser with measuring chamber

Info

Publication number: WO1998011929A1
Application number: PCT/EP1997/005064
Authority: WO
Inventors: Giuseppe Stradella
Original assignee: Tebro
Priority date: 1996-09-20
Filing date: 1997-09-16
Publication date: 1998-03-26
Also published as: FR2753791A1; FR2753791B1; JP2001508324A; EP0934089A1

Abstract

The invention concerns a device dispensing a powdery product, comprising a dispensing channel (20), a reservoir for the product (3) and means for measuring out (4) capable of being actuated manually for loading a dose of product into the measuring chamber (8) before each actuating of the device, said measuring chamber (8) being movable between a loading position, where it communicates with said reservoir (3), and a dispensing position, where it communicates with said dispensing channel (20). The invention is characterised in that said measuring chamber (8) is stressed by resilient means (19) in its loading position, where it is arranged outside said reservoir (3) so as to isolate said reservoir (3) from the environment, said dispensing device comprising sliding cam means (16, 17) integral with said measuring means (14) for displacing said measuring chamber (8) towards its dispensing position after a dose of the product has been loaded, and closing means (5) adapted for isolating said reservoir (3) from the environment when the measuring chamber (8) is not in its loading position.

Description

Powder dispenser with tilting dosing chamber.

The present invention relates to a device for dispensing powdered product, and more particularly to a dry powder inhaler (DPI), comprising a tilting metering chamber. In the field of DPI, used for the distribution of powdered products, in particular of drugs, two main families of devices are commonly used: devices of the multidose reservoir type, where all the powder is contained in a single reservoir, the device being provided with appropriate metering means for delivering each actuation of the device a determined quantity of medicament. devices of the pre-dosed type where each dose of powder is contained in separate cavities, hermetically closed, such as for example "blisters".

While systems of the pre-dosed type are capable of guaranteeing great stability of the drug, since each dose is perfectly hermetically isolated from the atmosphere and open only at the time of its delivery, these devices obviously require means for opening and distributing the dose contained in each cavity. Such devices are therefore expensive and sometimes complicated to manufacture and assemble. On the other hand, so-called multidose reservoir systems generally involve problems of drug stability. Thus, these devices are generally provided with a powder reservoir containing metering means as well as the medicament, said reservoir being connected with one or more metering chambers which are placed or moved in a distribution channel through which flows An air current, generated at the time of dispensing, thus expelling the powder.

A disadvantage of this type of device is that, at one time or another, the dosing chamber is simultaneously in contact with the reservoir and the external atmosphere. This situation can lead to contamination of the medicinal product, in particular humidification when the device is used in a humid environment, where, again for example when the user mistakenly exhales into the mouthpiece of the DPI when the reservoir is in contact with the outside atmosphere. All of the powder being contained in the same reservoir, contamination or humidification thereof automatically causes contamination or humidification of the entire product contained in the device.

WO 93/25258 discloses a DPI comprising a reservoir, a metering chamber and a metering element which transfers a dose of product from the reservoir to the metering chamber. This device is complicated and has a large number of parts which interact with each other. The manufacture and assembly of this device are therefore particularly complex and expensive.

Document WO 95/28980 discloses a DPI comprising an elastically deformable metering chamber by the flow of compressed air used to expel the dose of powder. This device can therefore only be used in DPIs of the active type where the dose is expelled by a flow of compressed air. In addition, through the use of an elastic metering chamber, its deformation capacity and therefore the reliability of the device can deteriorate after a large number of actuations.

The object of the present invention is to provide a device for dispensing pulverulent product in which the reservoir is completely and constantly separated from the external atmosphere. More particularly, the present invention aims to provide a powder inhaler of the multidose reservoir type in which said powder reservoir is completely and constantly separated from the external atmosphere.

The present invention also aims to provide such an inhalation device which can be used both with active DPI where the product is expelled by. a flow of compressed air or gas, as passive DPI, where the product is expelled by the flow of air created by one inhalation.

The present invention also aims to provide such an inhalation device whose operation is reliable and does not deteriorate even after a large number of actuations.

The present invention also aims to provide such an inhalation device which is simple and inexpensive to manufacture and assemble.

The present invention therefore relates to a device for distributing powdered product, comprising a distribution channel, a product reservoir and metering means which can be actuated manually to load a dose of product into a metering chamber before each actuation of the device, said device metering chamber being movable between a loading position, where it is in communication with said reservoir, and a dispensing position, where it is in communication with said distribution channel, said metering chamber being biased by elastic means in its loading position, where it is arranged outside said tank so as to isolate said tank from the atmosphere, said dispensing device comprising cam means integral with said metering means for moving said metering chamber towards its position distribution after loading a dose of product, and sealing means adapted to isolate said reservoir from the atmosphere when the metering chamber is not in its loading position.

Advantageously, said sealing means and said cam means are associated with said metering means so that the actuation of said metering means loads a dose of product into the metering chamber, isolating the reservoir by the closure means and the displacement of the metering chamber towards its dispensing position.

More particularly, said closure means comprise a plug disposed inside the tank, said plug being integral with said metering means.

Advantageously, said metering chamber is formed in a movable member, said movable member comprising a cam surface, and in which said cam means of the device are movable between two end positions, said cam means comprising a cam element which , in one of said end positions, cooperates with said cam surface of the movable member to move it into the dispensing position of the metering chamber.

Other characteristics and advantages of the present invention will appear during the following detailed description, given by way of nonlimiting example, with reference to the accompanying drawings, in which: FIG. 1 is a schematic sectional view of an inhaler according to the invention, in the loading position of the metering chamber; Figure 2 is a view similar to that of Figure 1, with the metering chamber in its dispensing position; Figure 3 is a schematic front view showing the metering chamber in its loading position; Figure 4 is a view similar to that of Figure

3 showing the metering chamber in its dispensing position; Figure 5 is a schematic top view showing part of the inhaler according to the invention; Figure 6 shows a schematic side sectional view of another embodiment of the inhaler according to the invention with the metering chamber in its loading position; and Figure 7 is a view similar to that of Figure

6 with the metering chamber in its dispensing position.

Referring to Figures 1 to 5, there is shown a device for dispensing powdered product, and more particularly, a dry powder inhaler (DPI) of the type commonly called "passive", that is to say in which the dose of product is expelled from the metering chamber by means of an air flow created by the inhalation of the user.

The DPI shown in Figures 1 and 2 comprises a hollow main body 1, substantially cylindrical in shape, provided with a mouthpiece 2 which is connected to a distribution channel 20 of the inhaler. This main body 1 carries a powder reservoir 3 which is connected to the distribution channel 20 via an opening 25 formed in the bottom of said reservoir 3. In the reservoir 3, metering means are provided (not shown) actuated by a manual actuating member 4 which can advantageously be rotatable relative to the main body 1. These metering means can for example be similar to those described in the document WO

93/18812, but it is understood that any other form of dosing means suitable for transferring a dose of product could be used in relation to the present invention. As shown in FIG. 2 but also in FIG. 7, closure means comprising a plug 5 are associated with said metering means for closing said reservoir 3 from the inside. Said plug 5 can advantageously be made of a resilient material.

The main body 1 also supports, on the side opposite to the reservoir 3 with respect to the distribution channel 20, a unit A comprising a base 12 having for example the shape of a plate, supporting a movable member 6 on which is disposed a chamber Advantageously, said movable member 6 is produced in the form of a flexible arm 6 and the dosing chamber 8 is produced inside a projection 7 projecting from said flexible arm 6 in the direction of said reservoir 3. Preferably, said flexible arm 6 further comprises at its end situated opposite the mouthpiece, a plate 9 in which a passage hole 10 is made. Advantageously, the plate 12 can be provided with a groove 13 disposed under said flexible arm to allow vertical movement of said flexible arm 6. The plate 12 preferably further comprises two air channels 14, more particularly visible in FIG. 5, the air channels 14 opening out from on the one hand in said distribution channel 20 and on the other hand in openings 15 associated with openings in the main body 1 (not shown) and which make it possible to create a current of air during the aspiration of the user to through the mouthpiece 2. According to the invention, the metering chamber 8 is movable between two positions, a loading position, where it is in communication with the interior of the reservoir 3, so that a dose of product can be loaded into the metering chamber 8 by means of the metering means, and a dispensing position, where the metering chamber 8 is in communication with the distribution channel 20, so that the dose of product can be expelled by an air current created by the inhalation of the user. According to the invention, in the loading position of the metering chamber 8, said projection 7 hermetically closes and thus isolates the reservoir 3 from the external atmosphere. For this purpose, the flexible arm 6 is preferably biased towards the loading position of the metering chamber by an elastic element 19, such as a spring. The device further comprises means 16, 17, in particular cam means, making it possible to move said metering chamber towards its dispensing position. Preferably, said cam means comprise a sleeve 16, movable together with the actuating button 4 of the metering means, said sleeve 16 being provided at a lower end with a cam element 17, produced for example in the form of 'a projecting projection, said cam element 17 being adapted to cooperate with the upper end 11 of the vertical plate 9 of said flexible arm 6. Thus, when the cam element 17 cooperates with said cam surface 11 of said flexible arm 11 , the latter is biased against the force of the spring 19 downwards, so that the projection 7 and therefore the metering chamber 8 is moved inside the distribution channel 20. Advantageously, the passage opening 10 made in said plate 9 of the flexible arm 6 is also simultaneously disposed opposite said mouthpiece 2 so that the distribution channel 20 is connected to said mouthpiece of the inhaler thus allowing the user aspirator to expel the dose contained in the dosing chamber 8.

According to the invention, the cap 5 is associated with the metering means (not shown) in such a way that when the actuation button 4 is actuated, they come close the opening 25 from the inside and thus isolate the reservoir 3 as soon as the dose of product has been. loaded into the metering chamber 8. In particular, the plug 5 is associated with the actuation button 4 so that it isolates the reservoir 3 before the cam element 17 cooperates with the cam surface 11 of the arm flexible 6 for moving the metering chamber 8 to its dispensing position. Thus, the invention guarantees that at no time does the reservoir 3 relate to the external atmosphere, so that any risk of contamination and / or humidification of the powder contained in said reservoir 3 is thus avoided . Similarly, after actuation of the inhaler, and when it is desired to use it again, actuation of the actuation button 4 first causes the cam element 17 to no longer cooperate with the surface of cam 11 of the flexible tab 6 so that it can rise, under the effect of the spring 19, in the loading position of the metering chamber, where said projection 7 isolates the reservoir from the external atmosphere, the plug 5 is only removed after the projection 7 has been placed in said opening 25 to isolate the reservoir.

When the metering chamber 8 is in its dispensing position, the user sucks in the mouthpiece 2, so that an air stream is created, the air entering said dispensing channel 20 through said channel. air 14 and emptying the metering chamber 8 and expelling the powder dose to the user. Advantageously, two openings 18 formed in the mouthpiece make it possible to create turbulence during the inhalation of the user to allow a better distribution of the dose of powder.

Referring to Figures 6 and 7, there is shown another embodiment of the invention in which the metering chamber 8 is emptied by means of a flow air created by an external device, such as a pump, and no longer created by the user's inhalation. Such DPI is commonly called "active DPI". In this embodiment, the air passages 14 are eliminated and the distribution channel 20 is connected to an opening 21 connected to said source of air current (not shown). When the metering chamber is in its dispensing position, shown in FIG. 7, the air flow device is actuated, so that an air flow passes through the opening 21, enters the distribution channel 20 and expels the dose contained in the metering chamber 8.

As an alternative to the embodiment shown in Figures 1 to 5, said movable member 6 may not include a projection 7, and the metering chamber may be directly provided inside said movable member 6, said movable member 6 being adapted to be pressed under said reservoir so as to hermetically isolate it from the external atmosphere, as shown in FIG. 6. In particular, the end of said member 6 comprising said metering chamber is produced so as to hermetically seal the opening 25 and therefore the reservoir 3. On the other hand, the elastic means 19 urging the metering chamber 8 in its loading position is produced, in the embodiment of FIGS. 6 and 7, in the form of a tongue elastic 19 in the form of a circular arc whose shape memory exerts the thrust when the metering chamber 8 is in the dispensing position of FIG. 7. Likewise, the cam means shown in FIGS. 6 and 7 have a lug 17 disposed at the lower end of a sleeve 16 secured to the rotary actuation button 4 of the metering means, said lug 17 cooperating with the cam surface 11 of the flexible tab 6, this cam surface 11 and said lug 17 being arranged substantially in the center of the main body 1 of the inhaler.

Although the invention has been described in relation to two particular embodiments, it is understood that any means equivalent to those described above can be used in relation to the present invention.

Claims

Claims:

1.- Device for dispensing powdered product, comprising a distribution channel (20), a product tank (3) and metering means (4) manually operable to load a dose of product into a metering chamber (8) before each actuation of the device, said metering chamber (8) being movable between a loading position, where it is in communication with said reservoir (3), and a dispensing position, where it is in communication with said distribution channel ( 20), characterized in that said metering chamber (8) is urged by an elastic means (19) in its loading position, where it is disposed outside of said tank (3) so as to isolate said tank ( 3) from the atmosphere, said dispensing device comprising cam means (16, 17) integral with said metering means (14) for moving said metering chamber (8) to its dispensing position after loading a dose of e product, and sealing means (5) adapted to isolate said reservoir (3) from the atmosphere when the metering chamber (8) is not in its loading position.

2.- Device according to claim 1, wherein said shutter means (5) and said cam means (16, 17) are associated with said metering means (4) so that the actuation of said metering means

(4) carries out the loading of a dose of product into the metering chamber, the isolation of the reservoir (3) by the closure means (5) and the displacement of the metering chamber (8) towards its position distribution.

3.- Device according to claim 1 or claim 2, wherein said sealing means comprise a plug (5) disposed inside the tank (3), said cap (5) being integral with said metering means (4).

4.- Device according to any one of the preceding claims, wherein said metering chamber (8) is formed in a movable member (6), said movable member (6) having a cam surface (11), and in which said cam means (16, 17) of the device are movable between two end positions, said cam means comprising a cam element (17) which, in one of said end positions, cooperates with said surface cam (11) of the movable member (6) to move it into the dispensing position of the metering chamber (8).