Inhalation device Number:6,792,945 from the United States Patent and Trademark Office (PTO) owispatent

Title: Inhalation device

Abstract: An inhalation device is described for use with a medicament pack in which at least one container for medicament in powder form is defined between two sheets peelably secured to one another. The device comprises means for peeling the sheets apart at an opening station to open the container; and an outlet, communicating with the opened container, through which a user can inhale medicament in powder form from the opened container.

Patent Number: 6,792,945 Issued on 09/21/2004 to Davies,   et al.

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Inventors:	Davies; Michael Birsha (Ware, GB), Hearne; David John (Luton, GB), Rand; Paul Kenneth (Letchworth, GB), Walker; Richard Ian (Ware, GB)
Assignee:	Glaxo Group Limited (Greenford, GB)
Appl. No.:	10/022,072
Filed:	December 13, 2001

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Related U.S. Patent Documents

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	Application Number	Filing Date	Patent Number	Issue Date
	456201	Dec., 1999
	166557	Oct., 1998	6032666
	979217	Nov., 1997	5860419	Jan., 1999
	552166	Nov., 1995	5590645	Mar., 1991
	467469	Jun., 1995	5873360	Feb., 1999
	175174	Dec., 1993
	663145	Mar., 1991

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Foreign Application Priority Data

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Mar 02, 1990 [GB]			9004781

Current U.S. Class:	128/203.15 ; 128/203.21
Current International Class:	A61M 15/00 (20060101)
Field of Search:	128/200.22,203.12,203.15,203.21

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Primary Examiner: Lewis; Aaron J.
Attorney, Agent or Firm: Smith; Robert J.

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Parent Case Text

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This is a division, of application Ser. No. 09/456,201, filed Dec. 7, 1999, which is a continuation of application Ser. No. 09/166,557, filed Oct. 5, 1998, now U.S. Pat. No. 6,032,666; which is a continuation of Ser. No. 08/979,217, filed Nov. 26, 1997, now U.S. Pat. No. 5,860,419, issued Jan. 19, 1999; which is a divisional of Ser. No. 08/467,469, filed Jun. 6, 1995, now U.S. Pat. No. 5,873,360, issued Feb. 23, 1999; which is continuation of Ser. No. 08/552,166, filed Nov. 2, 1995, now U.S. Pat. No. 5,590,645 issued Mar. 1, 1991; which is a continuation of Ser. No. 08/175,174, filed Dec. 28, 1993, now abandoned; which is a continuation of Ser. No. 07/663,145, filed Mar. 1, 1991, now abandoned. Each of these prior applications is hereby incorporated herein by reference, in its entirety.

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Claims

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What is claimed is:

1. An inhalation device for use with a medicament pack to be received in the device, in which pack a plurality of containers for medicament in powder form are defined, wherein the containers are spaced along the length of and defined between two peelable sheets secured to each other, the device comprising a body which is generally circular in plan view and has a circular rim and an axis of general rotation symmetry, and a cover mounted on said body for pivotal movement between a first position and a second position; an indexer for indexing each of the containers successively to an opening station when a medicament pack is received in said device; an opener for opening each of the containers at the opening station, said opener comprising a peeler positioned to engage peelable sheets of a container so as to peel apart the peelable sheets, opening the container; and a mouthpiece formed in said body and located substantially within the generally circular plan view, the mouthpiece communicating with the opened container when an medicament pack is received in said device, through which outlet a user can inhale medicament in powder form from the opened container, the outlet being exposed for use by movement of said cover from said first position to said second position; wherein the cover is mounted on said body for pivotal movement about said axis and comprises a side wall portion lying generally perpendicular to said axis and over an adjacent portion of said body, and an arcuate edge portion which extends from said side wall portion and partially around said rim.

2. A device according to claim 1, wherein the lid is pivotally mounted on the body by means of lugs.

3. A device according to claim 1, further comprising a dose monitor having indicia indicating use of the plurality of medicament containers.

4. A device according to claim 3, wherein the dose monitor is arranged to indicate at least approximately the number of unused medicament containers.

5. A device according to claim 3, wherein the dose monitor is arranged to indicate at least approximately the number of used medicament containers.

6. A device according to claim 3, wherein a window is provided in the body, the said indicia being visible through the window.

7. A device according to claim 6, wherein the window is visible to a user both when the cover is in its first position and when the cover is in its second position.

8. A device according to claim 1, adapted for operation where the medicament containers are disposed in an annular array.

9. A device according to claim 1, in which the said opener is provided with means for puncturing the containers when a medicament pack is received in said device.

10. A combination of an inhalation device and a medicament pack in which a plurality of containers for medicament in powder form reside, wherein the containers are spaced along the length of and defined between two peelable sheets secured to each other, the device comprising a body which is generally circular in plan view and has a circular rim and an axis of general rotation symmetry, and a cover mounted on said body for pivotal movement between a first position and a second position; an indexer for indexing each of the containers successively to an opening station; an opener for opening each of the containers at the opening station, said opener comprising a peeler positioned to engage peelable sheets of a container so as to peel apart the peelable sheets, opening the container; and a mouthpiece formed in said body and located substantially within the generally circular plan view, the mouthpiece communicating with the opened container, through which outlet a user can inhale medicament in powder form from the opened container, the outlet being exposed for use by movement of said cover from said first position to said second position; wherein the cover is mounted on said body for pivotal movement about said axis and comprises a side wall portion lying generally perpendicular to said axis and over an adjacent portion of said body, and an arcuate edge portion which extends from said side wall portion and partially around said rim.

11. A combination according to claim 10, wherein the lid is pivotally mounted on the body by means of lugs.

12. A combination according to claim 10, further comprising a dose monitor having indicia indicating use of the plurality of medica-ment containers.

13. A combination according to claim 12, wherein the dose monitor is arranged to indicate at least approximately the number of unused medicament containers.

14. A combination according to claim 12, wherein the dose monitor is arranged to indicate at least approximately the number of used medicament containers.

15. A combination according to claim 12, wherein a window is provided in the body, the said indicia being visible through the window.

16. A combination according to claim 15, wherein the window is visible to a user both when the cover is in its first position and when the cover is in its second position.

17. A combination according to claim 10, wherein the medicament containers are disposed in an annular array.

18. A combination according to claim 10, in which the said opener is provided with means for puncturing the containers.

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Description

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FIELD AND BACKGROUND OF THE INVENTION

This invention relates to an inhalation device by means of which a user can inhale medicament in the form of a powder.

Inhalation devices are known for use with blister packs in which the medicament is held in powder form in the blisters thereof. Such devices include a puncturing member which punctures each blister in turn, thus enabling the medicament to be inhaled therefrom. It is an object of the present invention to provide an inhalation device the design of which has the potential, if desired, to handle a medicament pack having a large number of discrete unit doses, without the device becoming unacceptably large.

BRIEF SUMMARY OF THE INVENTION

According to the present invention there is provided an inhalation device for use with a medicament pack in which at least one container for medicament in powder form is defined between two members peelably secured to one another, the device comprising means defining an opening station for the said at least one container; means for peeling the members apart at the opening station to open the container; and an outlet, communicating with the opened container, through which a user can inhale medicament in powder form from the opened container.

Preferably the medicament pack is formed from two elongate sheets which define a plurality of medicament containers spaced along the length thereof, means being provided for indexing each container in turn to the opening station.

The invention also provides a medicament pack for use in an inhalation device, the pack comprising an elongate strip formed from a base sheet having a plurality of recesses spaced along its length and a lid sheet hermetically but peelably sealed thereto to define a plurality of containers, each container having therein inhalable medicament in powder form. The strip is preferably sufficiently flexible to be wound into a roll.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a rear view of a first embodiment of the invention;

FIG. 2 is an axonometric exploded view of the components of the embodiment of FIG. 1;

FIGS. 3a, 3b and 3c are an axonometric view, a longitudinal section and an end view (partly broken away) showing a clutch used in the embodiment of FIGS. 1 and 2;

FIGS. 4a and 4b are an axial section and cross-section respectively, on a larger scale than FIGS. 1 and 2, of a mouthpiece which may be used in the first embodiment (or in some other embodiment);

FIG. 5 is a front view of a second embodiment, with a cover thereof removed to show the interior;

FIG. 6 is a rear view of the second embodiment, but showing the interior thereof

FIG. 7 is an axonometric front view of the second embodiment;

FIG. 8 is an axonometric rear view of the second embodiment;

FIG. 9 is an axonometric exploded view of the second embodiment;

FIG. 10 is a front view of a third embodiment, showing the interior structure thereof;

FIG. 11 is an axial view, on a larger scale, showing the mouthpiece of the third embodiment;

FIG. 12 is a view from below of the third embodiment;

FIGS. 13 to 16 show a fourth embodiment of the invention, FIG. 13 being an underplan view, FIG. 14 a section on line A--A in FIG. 13, FIG. 15 a section on line B--B in FIG. 13, and FIG. 16 an exploded view on a smaller scale;

FIGS. 16a to 16d show the fourth embodiment in successive stages of operation, and FIG. 16e is a section taken on line A--A in FIG. 16a;

FIGS. 17 to 20 show a fifth embodiment of the invention, FIG. 17 being an end view, FIG. 18 a section on line A--A in FIG. 17, FIG. 19 a section on line B--B in FIG. 17, and FIG. 20 an exploded view;

FIGS. 21 to 24 show a sixth embodiment of the invention, FIG. 21 being an end view, FIG. 22 a section on line A--A in FIG. 21, FIG. 23 a section on line B--B in FIG. 21, and FIG. 24 an exploded view;

FIGS. 25 to 29 show a modified clutch which may be used in those embodiments of the invention which require it, and are, respectively, a front view, a top view, a back view, a left side view and an axonometric view;

FIG. 30 is an exploded perspective view showing a further embodiment of clutch which may be used;

FIG. 31 is an exploded perspective view of yet another embodiment of clutch which may be used;

FIG. 31a is transverse section through the clutch shown in FIG. 31;

FIGS. 32 to 34 show successive positions of operation of another embodiment of the invention, in rear view; and

FIG. 35 is a perspective view on a larger scale showing an embodiment of medicament pack according to the invention.

DESCRIPTION OF PREFERRED EMBODIMENTS

Referring now to FIGS. 1, 2 and 3a to 3c, these show an inhalation device in which is mounted a flexible strip 1 defining a plurality of pockets 2 each of which contains a dose of medicament which can be inhaled, in the form of a powder. The strip 1 comprises a base sheet 3 in which blisters are formed to define the pockets 2, and a lid sheet 4 which is hermetically sealed to the base sheet 3 except in the region of the blisters, in such a manner that the lid sheet and the base sheet can be peeled apart. The sheets are sealed to one another over their whole width except for leading end portions thereof where they are preferably not sealed to one another at all. The lid and base sheets are each preferably formed of a plastics/aluminium laminate, and the lid and base sheets are preferably adhered to one another by heat sealing. By way of example, the lid material may be a laminate consisting of 50 gsm bleach kraftpaper/12 micron polyester (PETP) film/20 micron soft temper aluminium foil/9 gsm vinylic peelable heat seal lacquer (sealable to PVC), and the base material may be a laminate consisting of 100 micron PVC/45 micron soft temper aluminium foil/25 micron orientated polyamide. The lacquer of the lid material is sealed to the PVC layer of the base material to provide the peelable seal between the lid and base sheets.

The strip 1 is shown as having elongate pockets which run transversely with respect to the length of the strip. This is convenient in that it enables a large number of pockets to be provided in a given strip length. The strip may, for example, be provided with sixty or one hundred pockets, but it will be understood that the strip may have any suitable number of pockets.

The inhalation device comprises a body 10 defining three storage chambers, namely a chamber 11 in which the strip 1 is initially housed and from which it is dispensed, a chamber 12 for receiving the used portion of the base sheet 3, and a chamber 13 within which the used portion of the lid sheet can be wound up on a wheel 14. The chambers 11 and 12 contain respective curved leaf springs 28 and 29, the purpose of which is described below. The body defines a further chamber 15 which houses an index wheel 16. This has a plurality of grooves 17 extending parallel to the axis of the wheel 16. The grooves are spaced at a pitch which is equal to the distance between the centre lines of adjacent pockets 2. The chambers 11, 12, 13 and 15 are closed by a lid 30. The chamber 15 communicates with the chambers 11, 12 and 13 via passages 31, 33 and 32 respectively.

The chamber 15 communicates via a slit 18 which, in turn, extends upwardly within a mouthpiece 20. The slot 18 also communicates with air inlets, as will be described below with reference to the specific mouthpiece shown in FIGS. 4a and 4b. The mouthpiece 20 is provided with additional air inlets 21 shown here in the form of a pair of circular apertures, though they may be of some other shape, as they are in FIGS. 4a and 4b. The primary purpose of the additional air inlets 21 is to provide additional air to the user and thus reduce the resistance to inhalation, though they may serve one or more additional purposes, as they do in FIGS. 4a and 4b and as is described below with reference to those Figures.

A means is provided by which the user can rotate the index wheel and the lid wheel in steps of a predetermined size. This means comprises a ratchet wheel 22 and a gear wheel 23, both connected to rotate in unison with the index wheel 16, a lever 24 arranged to rotate about the same axis as the ratchet wheel 22 and gear wheel 23, but independently thereof, and a gear wheel 25 which meshes with the gear wheel 23 and is arranged to rotate the lid wheel 14. The lever 24 carries a pusher arm 26, the end of which is arranged to engage the teeth of the ratchet wheel 22. The teeth of the ratchet wheel are also engaged by a pawl 27 fixedly secured to the body 10. For reasons which will become apparent from the description below of the operation of this embodiment, the gear wheel 25 is not connected directly to the lid wheel 14, but is connected via a slipping clutch 50 which is housed within the lid wheel 14. The effect of the provision of this clutch is that slipping occurs between the lid wheel and the gear wheel 25 when the force required to rotate the lid wheel exceeds a predetermined amount.

The clutch 50 comprises a disc 51 provided with radially extending serrations 52, or other surface roughness, which is held in engagement with a similarly serrated or roughened surface 53 provided on an end face of the lid wheel 14 by a compression spring 54. The spring 54 bears at one end against an inwardly directed surface 55 of the lid wheel and at the other end against a nut 56 threaded on a bolt 57.

The device described above can be made so as to be reusable after the doses of medicament contained in the pockets 2 have all been dispensed. In that case, provision can be made for the user to gain access to the interior of the device, for example by removing the lid 30, so as to insert therein a fresh strip 1, for example in a cassette. Alternatively, however, the device may be made to be disposable once the strip 1 with which it is supplied has been used up.

In either event, when the device is first used the bulk of the strip 1 is within the chamber 11, kept in a relatively tight reel by the leaf spring 28, with a short portion at the leading end thereof passing out of the chamber 11 through the passage 31 to the index wheel 16. The foremost part of the leading end of the strip is peeled apart so that the leading end of the lid sheet 4 can be secured to the lid wheel 14, and so that the leading end of the base sheet 3 can enter the passage 33. The end of the lid sheet 4 is held in place on the lid wheel 14 by means of a key 34 which is a force fit in a slot 35 in the wheel 14.

A user desiring to use the device pushes the lever 24 in an anticlockwise direction, as viewed in FIG. 1, so that the pusher arm 26 urges the ratchet wheel 22 through an angle equal to the angular distance between two adjacent teeth. This causes the ratchet wheel 16 to rotate by an angular amount equal to the pitch of the groove 17 thereof and thus equal to the distance between two adjacent pockets 2 in the strip 1.

This brings a pocket 2 opposite the slot 18 in the body 10. Since the ratchet wheel 22 and gear wheel 23 move in unison, and since the gear wheel 25 meshes with the gear wheel 23, movement of the lever 24 also causes the lid wheel 14 to rotate. This peels a sufficient portion of the lid sheet 4 away from the base sheet 3 to expose the contents of the pocket 2 which is being brought into alignment with the slot 18.

When the user inhales through the mouthpiece 20 the flow of air which this produces entrains powder from the opened pocket, so that the powder is inhaled by the user. One way in which this can occur is explained in more detail below with reference to the embodiment of mouthpiece shown in FIGS. 4a and 4b. Each time the above procedure is repeated a further length of lid sheet is wrapped around the lid wheel 14 and a further length of base sheet enters chamber 12 through passage 33. The leaf spring 29 therein ensures that the base sheet is coiled up and does not snag on the wall of the chamber 12.

One effect of winding up the lid sheet on the lid wheel 14 is that the external diameter of the wheel plus the sheet wound thereon gradually increases. Were it not for the use of a slipping clutch to connect the gear wheel 25 to the lid wheel 14 this would have the result that successive operations of the lever 24 would try to cause a progressively longer length of lid sheet to be wound on to the lid wheel. The slipping clutch 50, however, avoids this effect, the clutch slipping each time by an amount sufficient to ensure that for every operation of the lever the amount of lid sheet wound on is precisely equal to the pitch of the pockets 2.

FIGS. 4a and 4b show a portion of the index wheel 16 with a pocket 2 therein, in conjunction with a mouthpiece which differs slightly from the mouthpiece 20 shown in FIGS. 1 to 3, and which is denoted by reference numeral 120. The mouthpiece 120 has air inlets 140, to which reference in general terms has already been made in connection with FIGS. 1 to 3, and a central powder outlet 119, one end of which is open to the pocket 2 and the other end of which opens into the interior of the mouthpiece 120.

When a user inhales through the mouthpiece 120 this causes air to flow in through the inlets 140 and thence through the pocket 2, into the powder outlet 119, and out through the mouthpiece 120. By thus directing the flow of air through the pocket 2, efficient entrainment of powder in the airflow is achieved, with consequent efficient emptying of the pocket. The mouthpiece 120 is provided with additional air inlets 121, shown here by way of example as being four in number, which open tangentially into the mouthpiece. When the user inhales air is drawn into the mouthpiece not only through the air inlets 140 but also through the air inlets 121, and the air entering through the inlets 121 produces a swirling airflow which helps to distribute powder effectively within the airflow and reduce the extent to which powder is deposited on the inside of the mouthpiece. This also helps to break up any aggregates of powder which may be present in the blister.

An alternative clutch arrangement is shown in FIGS. 25 to 29. In this, the index wheel 16 and the lid wheel 14 have respective toothed gear wheels 63 and 64 secured to them for rotation therewith. The direction of rotation is indicated by arrows in FIG. 27.

Gear wheel 63 has a toothed surface 65, with the teeth being provided continuously all the way round the surface 65 and at a constant pitch. By contrast, the gear wheel 64 has a toothed surface 66 from which some teeth are missing by virtue of the provision of radially extending slots 67. The circumferential width of each slot at the surface 66 is equal to one tooth pitch. The drawings show three such slots, but it should be understood that there could instead be one slot, two slots, or more than three slots. To one side of each of the slots 67, in fact upstream of each slot as considered in the direction of rotation of the gear wheel 64, a toothed section 68 is defined between the slot 67, and a narrow slit 69. The radially inner end of each slit 69 communicates with an aperture 70, so that each toothed portion 68 is connected to the remainder of the gear wheel 64 only by an arm 71. The gear wheel 64, or at least those portions thereof which provide the arms 71, is made of a material which permits the toothed portions 68 to flex resiliently back and forth in a circumferential direction. The rest position of the portions 68 is as shown in the drawings, but when a force is applied to a portion 68 in the direction of rotation of the gear wheel 64, the portion 68 can move so as to close the gap 67 at the radially outer end. This has the effect that a tooth is then "missing" not at the end of the slot 67 but at the end of the slit 69.

When the circumferential force applied by the gear wheel 63 to the gear wheel 64 is below a predetermined level the toothed portions 68 remain in their rest positions and the gear wheel 64 behaves just as if it had a continuous toothed surface like that of gear wheel 63. However, if the load exceeds a predetermined value, each time a toothed section 68 meshes with the gear wheel 63 it is moved circumferentially to close up the slot 67 at its outer end and open the slit 69. This movement of the toothed section 68 by a distance equal to the tooth pitch has the effect of producing slippage of the gear wheel 64 with respect to the gear wheel 69 equal to one tooth pitch. In this way, the illustrated arrangement is able to permit a total slippage of the gear wheels with respect to one another by a maximum of a distance equal to three times the tooth pitch per revolution, and hence a corresponding slippage of the lid wheel and index wheel with respect to one another. As will be appreciated, providing more or fewer toothed sections than the three illustrated will permit more or less than this maximum slippage.

A second embodiment of the inhalation device according to the invention is shown in FIGS. 5 to 9. This is intended for use with a strip 201, similar to the strip 1 used in the first embodiment except as regards the spacing of the pockets (for which see below). In many respects the second embodiment resembles the first embodiment, and components in the second embodiment which correspond in general terms to particular components in the first embodiment are denoted by the same reference numerals, but with the addition of 200. The main difference between the first embodiment and the second embodiment is that in the latter there is no index wheel corresponding to the index wheel 16 of the first embodiment. Instead, indexing of the strip 1, to ensure that each operation of the lever advances the strip by an amount equal to the pitch of the pockets, is achieved by a resiliently flexible arm 250 terminating in a tooth 252 which engages between adjacent pockets. Each time the lever 224 is operated the arm 250 is resiliently depressed as a pocket slides past the tooth 252 thereof, and the tooth then springs back into engagement with the strip to the rear of the pocket which has just passed it.

It will be appreciated that, as in the case of the first embodiment, the diameter of the lid wheel 214 with the lid sheet thereon gradually increases during operation. Since a slipping clutch cannot be used in this embodiment the effect just described is 73 compensated by having the spacing of the pockets 2 gradually increasing towards the rear end of the strip.

One other difference which will be noted between the first and second embodiments, is that in the latter the chambers 211 and 212 form a single composite chamber, unlike the separate chambers 11 and 12 in the first embodiment. However, this need not be so, and the first embodiment could use a single composite chamber and the second embodiment could use separate chambers.

FIGS. 10 to 12 show a third embodiment. In many respects this resembles the second embodiment, and components in the third embodiment which correspond in general terms to components in the second embodiment are denoted by the same reference numerals but with the addition of a further 100.

One difference which will be observed between the second and third embodiments is that in place of the lid wheel 114 a pair of wheels 314a and 314b are employed, with the lid sheet being gripped in the nip between the wheels 314a and 314b, which act as a mangle. These wheels are knurled or otherwise roughened to improve the grip between the wheels and the lid sheet. The used lid sheet is not wound up but is fed into a chamber 313, so that no problem arises, as it does in the first two embodiments, with the lid wheel attempting to wind up progressively longer lengths of lid as operation of the device continues.

FIG. 11 shows the mouthpiece to be of a somewhat different design to that shown in FIGS. 4a and 4b. The mouthpiece is shown as having a single air inlet 340 in place of the pair of air inlets 140, and the powder outlet 119 of FIGS. 4a and 4b is replaced by a mouthpiece portion 319 of reduced width. It should be understood, however, that the device shown in FIGS. 10 to 12 could be modifie