Insufflator

Abstract

This invention relates to an inhalation device for dispensing medicament in finely divided form for use in enabling a patient to inhale therefrom a dispersion of particulate material released from a capsule.

Description

SUMMARY OF THE INVENTION

Various insufflators have been proposed and used from which medicament can be inhaled directly into the lungs of a patient. These prior devices have generally relied upon the motion of the air being inhaled causing dispersion of the medicament into the air being inhaled. Typical of such insufflators are devices described by Altounyan et al., in U.S. Pat. Nos. 3,507,277 (1970); 3,635,219 (1972); and 3,669,113 (1972).

It has now been found that more reliable operation of an insufflator can be obtained where the patient can use the action of exhalation to distribute or disperse the medicament powder within a medicament chamber ready for reliable treatment upon inhalation drawing the dispersed powder from the chamber into the lungs of the patient.

According to the present invention there is provided an inhaling device for dispensing medicament in finely divided form comprising a housing, a rotor adapted to disperse a medicament in a chamber within the housing, a mouthpiece communicating with the chamber, a passage communicating between the chamber and the exterior of the housing, a drive portion of the rotor adapted to be driven by flow of air therepast, a second passage communicating the mouthpiece with the drive portion of the rotor, and valve means permitting flow of air from the mouthpiece past said drive portion upon exhalation into the mouthpiece and alternatively permitting air flow through said first mentioned passage and said chamber upon inhalation through the mouthpiece.

Preferably the drive portion is provided in a second chamber within the housing with the two chambers being separated by the rotor which may conveniently be in the form of a disk. The drive portion of the rotor can then comprise a plurality of vanes adapted to be driven by an exhaled flow of air from the mouthpiece through the second chamber.

While the device may be constructed so as to provide on the rotor mounting means for a single capsule, preferably so located as to extend radially outwards from the axis of the rotor so that when the outer end thereof is opened or pierced spinning of the rotor will help to distribute medicament centrifugally within the medicament chamber, in an alternative arrangement a plurality of capsules may be mounted in a ring around the axis of the rotor with these capsules being usable in turn as required by the patient. With this latter arrangement conveniently the plurality of capsules may be mounted as part of a blister pack which is secured to a face of the rotor. It will be apparent that both capsule mounting arrangements provide means for effectively dispersing medicament within the medicament chamber upon spinning of the rotor.

While it is possible for the capsules to be individually opened or pierced as required by the patient before use by opening of the housing it is preferred that capsule opening means are provided selectively operable for breaking or piercing a capsule carrier by the rotor. A convenient form of capsule opening means may comprise a plunger manually movable between a rest position and the capsule opening position, the plunger being spring biased to a rest position. If a portion of the rotor is engageable from the outside of the housing for permitting indexing movement of the rotor within the housing, the rotor can readily be indexed to align a full capsule with the capsule opening means permitting the capsules in the insufflator to be prepared for use without any opening of the housing by the patient being required. This is of particular convenience when the patient may require immediate relief, as all that he need do is take out the loaded insufflator, open a capsule using the capsule opening means, apply the mouthpiece to his mouth and quickly exhale before immediately inhaling to breath the dispersed and entrained particles of medicament into his lungs.

A particularly convenient form of valve means comprises nonreturn type flap valves covering ports through the housing, it being possible for such flap valves to comprise simple flaps of resilient plastic material which are normally in a position closing the ports associated therewith.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be further described, by way of example, with reference to the accompanying drawings, in which:

FIG. 1 is a front elevational view of a single dose form of insufflator embodying the invention;

FIG. 2 is a rear elevational view of the insufflator of FIG. 1;

FIG. 3 is an end elevational view of the insufflator as viewed from the right hand side of FIG. 1;

FIG. 4 is a fragmentary sectional view taken through the front and cap of the insufflator and showing the inhalation nonreturn valve;

FIG. 5 is a fragmentary sectional view taken through the rear end cap of the insufflator and showing the exhalation nonreturn valve; and

FIGS. 6 to 8 are views similar to FIGS. 1 to 3 but showing a multiple dose form of the insufflator.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to the drawings, and in particular to FIGS. 1 to 3, there is shown a single dose inhalation device comprising a substantially cylindrical housing 1 of high impact thermosetting plastics material provided with front and rear end caps which, in the illustrated embodiment of the invention, are transparent. These end caps are screwed into position so as to be removable, and at least one of said end caps carries a bearing portion, not apparent in the drawings, for rotatably supporting a rotor 4 within the housing. The rotor is of disk like form and separates the chamber within the housing into a first chamber portion at the rear thereof and a second or medicament chamber portion at the front thereof. The rotor 4 comprises on the front side thereof a mounting 12 for a capsule or other suitable container 14 for accomodating a medicament to be dispensed, and on the rear side thereof is formed with a series of radial vanes 6 which, in a manner to be described below, acts as a drive portion for rotating the rotor. An inhalation passage or port 3 is provided through the end cap at the front of the housing, while an exhalation passage or port 5 is provided through the end cap at the rear of the housing. A mouthpiece 2 has passage means which communicates with the interior of the housing and may comprise a divided entry providing a passage 11' leading to the aforementioned first chamber portion within the housing containing the vanes 6, and a passage 11 leading to the second or medicament chamber portion within the housing within which the rotor supports the medicament capsule 14.

Manually operable capsule opening means 7 are shown at the top of the housing as comprising a plunger 8 which is biased by a spring 9 to the rest position where an opening projection 10 is clear from contact with a capsule 14 carried by the rotor. The plunger 8 is manually depressable against the action of the spring 9 to cause the projection 10 to move towards the axis of the rotor whereby when a capsule 14 is aligned with the projection 10 such depression of the plunger will cause the projection 10 to break or pierce the end of the capsule 14.

Omitted in FIGS. 1 and 2 are valve means in the form of nonreturn inhalation and exhalation valves 13 and 15 which cooperate with the ports 3 and 5, respectively. These are shown in cross section in the detail views of FIGS. 4 and 5, the inhalation valve 13 being shown at the top of FIG. 4 in the position closing the port 3 which it adopts at rest and when a patient is exhaling through the mouthpiece 2 while the lower part of FIG. 4 shows the position adopted by the inhalation valve 13 when the patient is inhaling through the mouthpiece, air being sucked into the medicament chamber from the outside of the housing through the port 3. Similarly FIG. 5 shows the exhalation valve 15 in its closed position which it occupies during rest and when the patient is inhaling through the mouthpiece and its open position which it occupies when the patient is exhaling through the mouthpiece.

In both instances the valves are simple nonreturn flap valves which are made of resilient plastic material biased to closed position. The valve 13 is shown as mounted in a recess formed in an inner surface portion of the front end cap of the housing so that it does not project to a position where it could interfere with rotation of the rotor, while the valve 15 is shown as mounted on the outside of the rear end cap of the housing normally resiliently to close the port 5.

FIGS. 6 to 8 show an alternative embodiment of insufflator which is adapted to mount a plurality of capsules of medicament. The structure is generally similar to that of FIGS. 1 to 3 with a housing 21 provided with a mouthpiece 22 and having in front and rear end caps, respectively, an inhalation port 23 and an exhalation port 25 provided with nonreturn flap valves similar to those illustrated in FIGS. 4 and 5. A rotor 24 provided with vanes 26 on its rear side is mounted for rotation within the housing, the vanes being drivable by flow of air from the mouthpiece 22 through a first chamber portion containing the vanes and out through the exhalation port 25. On the front side of the disk like rotor a plurality of mounting means 32 are provided for capsules or other suitable containers 34 for accomodating a medicament to be dispersed. The mounting means 32 are arranged to hold the capsules extending radially from the axis of the rotor, whereby upon rotation of the rotor a dispersion of the medicament from a capsule will be assisted by centrifugal action, the outer end of the capsule being the part of the capsule opened.

In this embodiment no opening means corresponding with the opening means 7 of the first embodiment are illustrated although such may be provided if desired. Instead, the user removes the front end cap of the housing in order manually to open a capsule before use of the insufflator, or he can use a piercing instrument to extend from the mouthpiece to penetrate the end of a capsule aligned with the mouthpiece passage 31.

As before, a portion of the rotor may be engageable exteriorly of the housing to permit indexing of a capsule for opening.

Instead of having individual mounting means for the various capsules they may be formed as a single blister pack which can be attached to the front face of the rotor 24.

In an alternative arrangement the rotor and medicament filled capsules may themselves comprise an entirely replaceable unit which can be provided within the housing for replacement by another full unit once all the individual doses have been used.

During use of the insufflator the patient, having loaded the device with one or more capsules, either opens one of the capsules manually before replacing the end cover on the housing or utilizes an opening means 7 to open the capsule after closure of the housing. The patient then puts the mouthpiece to his mouth and exhales strongly therethrough, whereupon the air exhaled passes through the passage 11' or 31 into the first chamber portion within the housing flows past the vanes 6 or 26 and out through the exhalation port 5 or 25, causing the rotor to spin at high speed to disperse medicament from the opened capsule into the medicament chamber portion within the housing. The patient then immediately inhales strongly through the mouthpiece, whereupon the valve 15 closes and the valve 13 opens to permit air to be inhaled through inhalation port 3 or 23 and said medicament chamber portion, carrying with it the air entrained medicament from said chamber portion into the lungs of the patient.

Claims

What is claimed is:

1. An inhalation device comprising a housing having a first chamber portion and a medicament chamber portion therewithin and having a single mouthpiece formed with passage means communicating respectively with said chamber portions; said housing being provided with an air exhaust port communicating with said first chamber portion and an air inlet port communicating with said medicament chamber portion; a rotor mounted within said housing; a drive portion on said rotor driven by said air flow through said first chamber portion; means for dispersing a medicament within said medicament chamber portion; and air flow control valve means for causing air flow through said first chamber portion and said exhaust port by exhalation through said mouthpiece to effect rotor movement and for causing air flow through said inlet port and said medicament chamber portion to effect entrainment of said medicament by inhalation through said mouthpiece.

2. A device according to claim 1 wherein said dispersing means is carried by said rotor within said medicament chamber.

3. A device according to claim 1 wherein said dispersing means comprises means on said rotor for mounting at least one capsule of medicament.

4. A device according to claim 1 wherein said dispersing means comprises means on said rotor for mounting a plurality of capsules of medicament in spaced relation about the axis of said rotor.

5. Apparatus according to claim 3 wherein said dispersing means comprises a replaceable unitary multiple capsule pack mounted on said rotor.

6. Apparatus according to claim 3 wherein a plurality of capsules of medicament are mounted on said rotor and form therewith a replaceable unit.

7. A device according to claim 3 wherein means is provided for opening a capsule carried by said housing.

8. A device according to claim 7 wherein the capsule opening means comprises a plunger manually movable between a rest position and an operative position in which it is adapted to penetrate a capsule carried by said rotor.

9. A device according to claim 8 wherein said plunger is spring biased toward its rest position.

10. Apparatus according to claim 1 wherein the drive portion on said rotor comprises a plurality of vanes in said first chamber portion.

11. Apparatus according to claim 1 wherein said valve means comprises a first non return valve controlling air flow through said exhaust port and a second non return valve controlling air flow through said inlet port.

12. Apparatus according to claim 11 wherein said non return valves are normally closed flap valves.

13. Apparatus according to claim 1 wherein said passage means comprises separate first and second passages communicating respectively with said first and medicament chamber portions.

14. Apparatus according to claim 13 wherein said first passage is positioned to direct exhaled air at the drive portion of said rotor in a manner tending to cause rotation thereof.