Training device

1. A training device for training a user to use a pressurized metered dose inhaler, the device comprising:

a body;

an air expulsion means for expelling air without a release of any propellant gas along an air flow path, wherein the air expulsion means comprises a body element which has a variable volume or comprises a body element which has a variable volume portion such that, as the volume of the variable volume body element/portion is reduced, air is expelled from the variable volume body element/portion along the air flow path; and

an actuator for actuation of the air expulsion means;

wherein the air flow path comprises a restriction such that upon expulsion of air along the air flow path, an audible signal is generated; and

wherein the air flow path extends from the air expulsion means to an outlet port in the actuator, such that when the actuator is actuated by the user the air is expelled out of the outlet port and away from the user's mouth.

2. The device according to claim 1 , wherein the actuator forms a sliding fit within the body and depression of the actuator into the body effects actuation of the air expulsion means.

3. The device according to claim 1 , wherein the body has a tubular portion having an open upper end and a closed lower end and wherein the actuator comprises a tubular element having a closed upper end and an open lower end which is inserted into the open upper end of the tubular portion of the body.

4. The device according to claim 1 , wherein the variable volume body/portion has a wall portion which is deformable upon actuation of the actuator, or the variable body/portion is entirely defined by walls which are deformable upon actuation of the actuator.

5. The device according to claim 4 , wherein the device further comprises a resistance member for abutment with the variable volume body/portion such that upon actuation of the air expulsion means, the variable volume body/portion is pressed against the resistance member thus causing deformation of the deformable wall portion/walls.

6. The device according to claim 1 , wherein the air expulsion means comprises bellows.

7. The device according to claim 1 , wherein the restriction in the air flow path is proximal to the outlet port.

8. The device according to claim 7 , wherein the device further comprises a sound box in the air flow path adjacent the outlet port.

9. The device according to claim 1 , wherein the restriction in the air flow path is an orifice having a reduced cross-sectional area.

10. The device according to claim 1 , wherein the air flow path comprises a plurality of restrictions.

11. The device according to claim 10 , wherein the air flow path comprises an upstream orifice having a smaller cross-sectional area than the air flow path and a downstream orifice having larger cross-sectional area than the upstream orifice.

12. The device according to claim 3 , wherein the device further comprises a body extension and a sealing plate is provided between the body extension and the tubular portion of the body, and wherein the device further comprises at least one air inlet defined at least partly by the body extension.

13. The device according to claim 12 , comprising at least one notch in the body extension, the at least one notch extending from an open end of the body extension towards the body.

14. The device according to claim 13 , further comprising two opposed notches in the body extension.

15. The device according to claim 12 , wherein the body extension comprises a tubular extension extending from the closed lower end of the tubular portion of the body, the tubular extension comprising a receiving portion with an open end distal the body for receiving the attachment end of a spacer, the tubular extension further comprising a connecting portion between the receiving portion and the body, wherein there is a stepped join/ridge or an intermediate portion having a plurality of stop points between the receiving portion and the connecting portion.

16. The device according to claim 15 , further comprising two opposed notches, aligned either side of the tubular extension, wherein the sealing plate comprises a deviator in alignment with the two notches.

17. The device according to claim 16 , wherein the tubular extension comprises a stepped join/ridge between the connecting portion and the receiving portion and the total area of each notch in the connecting portion is between 20 and 150 mm 2 .

18. The device according to claim 16 , wherein the tubular extension comprises an intermediate portion having at least a first stop point proximal the connecting portion and a second stop point proximal the receiving portion and the first total area of each notch defined by the connecting portion and the intermediate portion between the connecting portion and the first stop point is smaller than the second total area of each notch defined by the connecting portion and the intermediate portion between the connecting portion and the second stop point and wherein both the first total area and the second total area are between 20 and 150 mm 2 .

19. The device according to claim 1 , further comprising a counter for providing an indication of time elapsed since actuation of the air expulsion means.