Training device

Abstract

The present invention provides a training device for training a user to use a pressurised metered dose inhaler (PMDI). The device comprises a body, air expulsion means (e.g. bellows) for expelling air along an air flow path and an actuator for actuation of the air expulsion means. The air flow path comprises a restriction such that upon expulsion of air along the air flow path, an audible signal is generated. The audible signal mimics that generated during use of a PMDI.

Claims

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.sup.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.sup.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.

Description

BRIEF DESCRIPTION OF DRAWINGS

(1) A preferred embodiment of the present invention will now be described with reference to the accompanying Figures in which:

(2) FIG. 1 shows a front view of the first embodiment of the present invention;

(3) FIG. 2 shows a bottom view of the first embodiment of the present invention;

(4) FIG. 3 shows a top view of the first embodiment of the present invention;

(5) FIG. 4 shows a cross-sectional view along line A-A shown in FIG. 1;

(6) FIG. 5 shows a cross-sectional view along a line at ninety degrees to line A-A;

(7) FIG. 6 shows a cross-sectional view through a second preferred embodiment;

(8) FIG. 7 shows a cross-section view through the second preferred embodiment when in sit within a PMDI body;

(9) FIG. 8 shows a cross-section through a counter which may be used with the first or second embodiment;

(10) FIG. 9 shows a front perspective view of the display of the counter; and

(11) FIGS. 10A and 10B show a front perspective and rear respective view of a replaceable body extension.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

(12) FIGS. 1 to 5 show a first preferred embodiment of a training device for training a user to use a pressurised metered dose inhaler (PMDI). The Figures show the device in combination with a FLO-TONE pMDI attachment spacer.

(13) The device 1 comprises a body 2, an integral body extension 3 and an actuator 4 for actuation of air expulsion means 5 (shown in the cross-sectional views in FIGS. 4 and 5 and discussed further below).

(14) The device 1 is shaped like a PMDI, the body 2 having a cylindrical portion 6 with an open upper end 7 and a closed lower end 8 and the body extension 3 extending at an angle (between 90 and 100 degrees) relative to the axis of the cylindrical portion 6 from proximal the closed lower end 8. The closed lower end 8 has a depression and a grip 37 for accommodating the user's thumb when the device is being held.

(15) The actuator 4 comprises a cylindrical element 9 having a closed upper end 10 and an open lower end 11 which is inserted into the open upper end 7 of the cylindrical portion 6 of the body 2 (the diameter of the actuator 4 being less that the diameter of the cylindrical portion 6 of the body 2.)

(16) The cylindrical element 9 forms a sliding fit within the cylindrical portion 6 of the body 2 and depression of the actuator 4 into the body 2 effects actuation of the air expulsion means 5. The closed upper end 10 of the actuator 4 includes a depression for receiving a user's finger for depression of the actuator 4 into the body 2.

(17) The actuator 4 comprises cooperation means for cooperating with the body to prevent rotational movement within the body and/or to prevent removal of the actuator from the body. The actuator cooperation means comprises a groove 12 which cooperates with a complementary ridge 13 inside the body for preventing rotational movement of the actuator 4 within the body 2.

(18) The actuator cooperation means additionally comprises an annular enlargement 14 of at least part of the rim of the open lower end 11 of the cylindrical element 9 of the actuator 4, the annular enlargement 14 for cooperating with lugs (not shown) on the inside of the walls of the cylindrical portion 6 of the body 2 for preventing removal of the actuator 4 from the body 2.

(19) The air expulsion means 5 are for expelling air along an air flow path. The air expulsion means 5 comprises piston bellows having a cylindrical portion defined by corrugated walls 15 and a closed lower end 16. The volume of the cylindrical portion of the bellows is reducible by compression of the corrugated walls 15 upon actuation by depression of the actuator 4 into the body 2. As the volume of the bellows is decreased, air is expelled along the air flow path.

(20) The body 2 comprises a resistance member 17 which is an annular projection upstanding into the cylindrical portion 6 from the closed end 8 of the cylindrical portion 6 for abutment with the closed lower end 16 of the piston bellows.

(21) The air expulsion means 5 and actuator 4 are connected by an insert 18 and movement (i.e. depression of the actuator 4) is transferred directly to the air expulsion means 5 through the insert 18. The insert 18 comprises a duct 19 defining the air flow path from the air expulsion means 5 to proximal the closed upper end 10 of the actuator 4. The duct 19 is received in a seat 20 provided on the inside of the closed upper end 10 of the actuator 4.

(22) When the air flow path reaches the closed upper end 10 of the actuator 4, it is deflected through 90 degrees through an orifice 21 in the duct 19, the orifice 21 having a smaller cross-sectional area than the duct 19. The orifice 21 constitutes a first (upstream) restriction in the air flow path.

(23) The air flow path further includes a second (downstream) orifice 22, the second orifice 22 having larger cross-sectional area than the first upstream orifice 21. The upstream orifice 21 is closer to the air expulsion means 5 than the downstream orifice 22.

(24) Upon expulsion of air (from the air expulsion means 5) along the air flow path, the smaller upstream orifice 21 creates a high speed jet of air and the larger downstream orifice 22 creates a turbulent air flow which generates an audible signal.

(25) Both the upstream and downstream orifices 21, 22 are defined by the insert 18 connecting the air expulsion means 5 and actuator 4. The first (upstream) orifice is provided in the duct 19 of the insert just after the 90 degree deflection of the air flow path. The insert 18 comprises a flange 23 extending from the duct 19 and supporting an upstanding plate 24, the upstanding plate 24 partially defining the downstream orifice 22 which is in alignment with and spaced from the upstream orifice 21. The upstanding plate 24 extends to a lug 25 extending down from the inside of the closed upper end 10 of the actuator 4. The lug 25 partially defines the upstream orifice 22.

(26) The air flow path extends from the air expulsion means 5 to an outlet port 26 in the actuator 4. The downstream orifice 22 is proximal the outlet port 26 so that any damping by the body 2 and the actuator 4 of the audible signal generated by the air as it passes through the downstream orifice 22 is minimised.

(27) To further increase the volume of the audible signal, a sound box 27 is provided in the air flow path, adjacent the outlet port 26. The air flow path passes through the sound box 27 after passing through the orifices 21, 22 and the sound box 27 acts to amplify the audible signal generated.

(28) The sound box 27 is defined by the walls of cylindrical element of the actuator 4 surrounding the outlet port 26, the closed upper end 10 of the actuator 4, the flange 23 depending from the duct 19 of the insert (where the flange 23 extends up to the walls of cylindrical element of the actuator 4) and by inner walls (not shown) depending from the inside of the closed upper end 10 of the cylindrical element of the actuator 4, the inner walls extending downwards to the flange 23 and across to the walls of the cylindrical element of the actuator 4. The inner walls extend either side of the lug 25 which at least partly defines the second, upstream orifice 22.

(29) A sealing plate 28 (shown in FIG. 4) is provided between the body extension 3 and the cylindrical portion 6 of the body. The sealing plate 28 has a smooth surface and forms a smooth join with the body extension 3 i.e. there are no abrupt deflections between the sealing plate 28 and the walls of the body extension 3.

(30) The body extension 3 comprises a tubular extension extending from the closed lower end 8 of the cylindrical portion 6 of the body 2. The tubular extension comprises a receiving portion 29 with an open end distal the body 2 for receiving the attachment end 30 of a spacer 31 in a press-fit arrangement. The tubular extension comprises a connecting portion 32 which connects the receiving portion 29 to the body 2. There is preferably a stepped join 33 between the receiving portion 29 and the connecting portion 32 which limits the extent to which the spacer 31 can be fitted onto the tubular extension so that the receiving portion 29 may be enclosed within the spacer 31 but the connecting portion 32 remains exposed.

(31) Two air inlets 34, 34 are defined by opposing, aligned notches in the body extension 3 extending from the open end of the receiving portion 29 and through the connecting portion 32 to the sealing plate 28. The two air inlets are of equal size and each has an area of around 10 mm.sup.2, 28.5 mm.sup.2, 30 mm.sup.2, 59 mm.sup.2 or 66 mm.sup.2these areas provide air flow rates and back pressure values which match five commonly used PMDIs. It should be noted that the area of the air inlets is equivalent to the area of the notches in the connecting portion 32 of the tubular extension.

(32) The sealing plate 28 is provided with a deviator 35 in alignment with the two air inlets 34, 34. The deviator 35 acts prevent the two streams of the inhalation flow path entering through the two air inlets 34, 34 from buffeting each other and creating turbulence. The deviator 35 is a circular bump. The bump has a height such that it protrudes from the sealing plate by an amount that is around of the length of the connecting portion 32 (i.e. from the sealing plate 28 to receiving portion 29) of the tubular extension.

(33) The device further includes a counter (shown in FIGS. 8 and 9) for providing an audible indication of time elapsed since actuation of the air expulsion means 5.

(34) The Figures show the device in combination with a spacer 31. This spacer includes a sound generator 36 which generates an audible tone when the correct air flow rate for drug delivery is achieved.

(35) Accordingly, the user affixes the attachment end 30 of the spacer 31 to the body extension 3 and inhales until the tone indicating the correct flow rate is generated by the spacer 31. At that time, the user depresses the actuator 4 to activate the air expulsion means 5. The air expulsion means 5 acts to force air through the restricted air flow path thus generating an audible signal that is comparable to the sound generated by the propellant gases upon depression of a canister into the body of a PMDI. The user is then instructed to continue breathing in after hearing the audible signal generated by the device 1 for as long as they can whilst maintaining the tone generated by the spacer 31. Preferably, the counter will provide some indication of time elapsed and the user should aim to keep inhaling for at least five seconds after depression of the actuator 4/actuation of the air expulsion means 5. Accordingly, by using the device 1 of the present invention, especially in combination with the FLO-TONE pMDI attachment spacer 31, a user can learn to use a PMDI correctly by undergoing a realistic training experience where the actions of using the device and the sounds generated by the device accurately mimic those of a PMDI.

(36) FIGS. 6 and 7 show a second preferred embodiment of a training device for training a user to use a pressurised metered dose inhaler (PMDI). FIG. 7 shows the device in combination with an empty PMDI body with a FLO-TONE pMDI attachment spacer attached.

(37) The device 1 comprises a body 2 and an actuator 4 for actuation of air expulsion means 5.

(38) The body 2 has a cylindrical portion 6 having an open upper end 7 and a closed lower end 8.

(39) The actuator 4 comprises a cylindrical element 9 having a closed upper end 10 and an open lower end 11 which is inserted into the open upper end 7 of the cylindrical portion 6 of the body 2 (the diameter of the actuator 4 being less that the diameter of the cylindrical portion 6 of the body 2.)

(40) The cylindrical element 9 forms a sliding fit within the cylindrical portion 6 of the body 2 and depression of the actuator 4 into the body 2 effects actuation of the air expulsion means 5. The closed upper end 10 of the actuator 4 includes a depression for receiving a user's finger for depression of the actuator 4 into the body 2.

(41) The actuator 4 comprises cooperation means for cooperating with the body to prevent rotational movement within the body and/or to prevent removal of the actuator from the body. The actuator cooperation means comprises a groove 12 which cooperates with a complementary ridge inside the body for preventing rotational movement of the actuator 4 within the body 2.

(42) The actuator cooperation means additionally comprises an annular enlargement 14 of at least part of the rim of the open lower end 11 of the cylindrical element 9 of the actuator 4, the annular enlargement 14 for cooperating with lugs (not shown) on the inside of the walls of the cylindrical portion 6 of the body 2 for preventing removal of the actuator 4 from the body 2.

(43) The air expulsion means 5 are for expelling air along an air flow path. The air expulsion means 5 comprises piston bellows having a cylindrical portion defined by corrugated walls 15 and a closed lower end 16. The volume of the cylindrical portion of the bellows is reducible by compression of the corrugated walls 15 upon actuation by depression of the actuator 4 into the body 2. As the volume of the bellows is decreased, air is expelled along the air flow path.

(44) The closed lower end 8 of the cylindrical portion 6 of the body 2 is in abutment with the closed lower end 16 of the piston bellows.

(45) The air expulsion means 5 and actuator 4 are connected by an insert 18 and movement (i.e. depression of the actuator 4) is transferred directly to the air expulsion means 5 through the insert 18. The insert 18 comprises a duct 19 defining the air flow path from the air expulsion means 5 to proximal the closed upper end 10 of the actuator 4. The duct 19 is received in a seat 20 provided on the inside of the closed upper end 10 of the actuator 4.

(46) When the air flow path reaches the closed upper end 10 of the actuator 4, it is deflected through 90 degrees through an orifice 21 in the duct 19, the orifice 21 having a smaller cross-sectional area than the duct 19. The orifice 21 constitutes a first (upstream) restriction in the air flow path.

(47) The air flow path further includes a second (downstream) orifice 22, the second orifice 22 having larger cross-sectional area than the first upstream orifice 21. The upstream orifice 21 is closer to the air expulsion means 5 than the downstream orifice 22.

(48) Upon expulsion of air (from the air expulsion means 5) along the air flow path, the smaller upstream orifice 21 creates a high speed jet of air and the larger downstream orifice 22 creates a turbulent air flow which generates an audible signal.

(49) Both the upstream and downstream orifices 21, 22 are defined by the insert 18 connecting the air expulsion means 5 and actuator 4. The first (upstream) orifice is provided in the duct 19 of the insert just after the 90 degree deflection of the air flow path. The insert 18 comprises a flange 23 extending from the duct 19 and supporting an upstanding plate 24, the upstanding plate 24 partially defining the downstream orifice 22 which is in alignment with and spaced from the upstream orifice 21. The upstanding plate 24 extends to a lug 25 extending down from the inside of the closed upper end 10 of the actuator 4. The lug 25 partially defines the upstream orifice 22.

(50) The air flow path extends from the air expulsion means 5 to an outlet port 26 in the actuator 4. The downstream orifice 22 is proximal the outlet port 26 so that any damping by the body 2 and the actuator 4 of the audible signal generated by the air as it passes through the downstream orifice 22 is minimised.

(51) To further increase the volume of the audible signal, a sound box 27 is provided in the air flow path, adjacent the outlet port 26. The air flow path passes through the sound box 27 after passing through the orifices 21, 22 and the sound box 27 acts to amplify the audible signal generated.

(52) The sound box 27 is defined by the walls of cylindrical element of the actuator 4 surrounding the outlet port 26, the closed upper end 10 of the actuator 4, the flange 23 depending from the duct 19 of the insert (where the flange 23 extends up to the walls of cylindrical element of the actuator 4) and by inner walls (not shown) depending from the inside of the closed upper end 10 of the cylindrical element of the actuator 4, the inner walls extending downwards to the flange 23 and across to the walls of the cylindrical element of the actuator 4. The inner walls extend either side of the lug 25 which at least partly defines the second, upstream orifice 22.

(53) The device further includes a counter (shown in FIGS. 8 and 9) for providing an audible indication of time elapsed since actuation of the air expulsion means 5.

(54) FIG. 7 shows the device 1 within a PMDI body 38 in combination with a spacer 31. This spacer includes a sound generator 36 which generates an audible tone when the correct air flow rate for drug delivery is achieved.

(55) Accordingly, the user inserts the device 1 into the cylindrical portion 39 of the PMDI body so that the closed lower end 8 of the cylindrical portion 6 of the body is in abutment with the valve seat 40. The user affixes the attachment end 30 of the spacer 31 to the PMDI mouthpiece 41 and inhales until the tone indicating the correct flow rate is generated by the spacer 31. At that time, the user depresses the actuator 4 to activate the air expulsion means 5. The air expulsion means 5 acts to force air through the restricted air flow path thus generating an audible signal that is comparable to the sound generated by the propellant gases upon depression of a canister into the PMDI body. The user is then instructed to continue breathing in after hearing the audible signal generated by the device 1 for as long as they can whilst maintaining the tone generated by the spacer 31. Preferably, the counter will provide some indication of time elapsed and the user should aim to keep inhaling for at least five seconds after depression of the actuator 4/actuation of the air expulsion means 5. Accordingly, by using the device 1 of the present invention, especially in combination with the FLO-TONE pMDI attachment spacer 31, a user can learn to use a PMDI correctly by undergoing a realistic training experience where the actions of using the device and the sounds generated by the device accurately mimic those of a PMDI.

(56) FIGS. 8 and 9 show a counter 42 for use with the first or second embodiment for providing a visual indication of the time elapsed since actuation of the air expulsion means. The counter 42 comprises a liquid-filled reservoir 43 connected to a second air flow path (not shown), the second air flow path extending from the bellows to a second outlet 44 in the actuator. The second outlet 44 is connected to a plunger 45 which seals the liquid-filled reservoir 43. The liquid-filled reservoir is connected to an upstanding capillary tube 46 by a U-tube 47. The capillary tube 46 is visible to the user as they use the device through graduations 48 on a front screen 49 of a display 50 sealed with a fluid-impermeable seal 51. As the actuator 4 is depressed into the cylindrical portion of the body 6, air is expelled along the second air flow path to the second outlet 44 and this actuates the plunger 45 which increases the pressure in the liquid-filled reservoir 43. This causes the liquid to rise within the upstanding tube 46. The viscosity of the liquid in the reservoir is selected such that, after rising within the tube 46, it recedes back into the reservoir 43 (and the U-tube 47) at a predetermined rate. The predetermined rate is such that it recedes back into the reservoir over a time period of around 5 seconds. The graduations 48 on the display indicate to the user the rate at which the liquid is receding allowing them to determine the length of time for which they have been inhaling since actuation of the air expulsion means 5.

(57) FIGS. 1 to 5 show an embodiment with an integral body extension 3. Alternative embodiments may be identical to that shown in FIGS. 1 to 5 but with a detachable/replaceable body extension 3 as shown in FIGS. 10A and 10B.

(58) The detachable body extension 3 comprises a sealing plate 28 which has a smooth surface and forms a smooth join with the walls of the body extension 3 i.e. there are no abrupt deflections between the sealing plate 28 and the walls of the body extension 3.

(59) The body extension 3 comprises a tubular extension having a receiving portion 29 with an open end for receiving the attachment end 30 of a spacer 31 in a press-fit arrangement. The tubular extension further comprises a connecting portion 32. There is preferably a stepped join 33 between the receiving portion 29 and the connecting portion 32 which limits the extent to which the spacer 31 can be fitted onto the tubular extension so that the receiving portion 29 may be enclosed within the spacer 31 but the connecting portion 32 remains exposed.

(60) The rear surface 52 of the sealing plate 28 has connection means comprising 2 projections 53, 53 which are insertable into two holes (not shown) at the lower end of the cylindrical portion 6 of the body 2 to form a device which resembles the shape of a PMDI. The body extension 3 is releasably attachable to the body 2 to that, after use, it can be removed and discarded or cleaned. Alternatively, the connection means comprising two projections 53, 53 are insertable into the expansion chamber/actuator nozzle region of an empty PMDI body.

(61) Two air inlets 34, 34 are defined by opposing, aligned notches in the body extension 3 extending from the open end of the receiving portion 29 and through the connecting portion 32 to the sealing plate 28. The two air inlets are of equal size and each has an area of around 10 mm.sup.2, 28.5 mm.sup.2, 30 mm.sup.2, 59 mm.sup.2 or 66 mm.sup.2these areas provide air flow rates and back pressure values which match five commonly used PMDIs. It should be noted that the area of the air inlets is equivalent to the area of the notches in the connecting portion 32 of the tubular extension.

(62) The sealing plate 28 is provided with a deviator 35 in alignment with the two air inlets 34, 34. The deviator 35 acts prevent the two streams of the inhalation flow path entering through the two air inlets 34, 34 from buffeting each other and creating turbulence. The deviator 35 is a circular bump. The bump has a height such that it protrudes from the sealing plate by an amount that is around of the length of the connecting portion 32 (i.e. from the sealing plate 28 to receiving portion 29) of the tubular extension.