Powder jet dispenser for medicament inhalation therapies

• US 5,546,932 A
• Filed: 11/15/1994
• Issued: 08/20/1996
• Est. Priority Date: 03/25/1992
• Status: Expired due to Fees

• Current Assignee: TEBRO SA
• Original Assignee: TEBRO SA
• Inventors: Galli, Rosaria
• Primary Examiner(s): Yan, Ren
• Assistant Examiner(s): RACITI, ERIC
• Application Number:
  US08/313,033
• Time in Patent Office: 644 Days
• Field of Search: 128/200.14, 128/200.22, 128/202.21, 128/203.15, 128/203.19, 128/203.21, 128/203.23
• US Class Current: 128/203.15
• CPC Class Codes: A61M 15/0065 Inhalators with dosage or measuring devices A61M15/0028 takes precedence; dosage devices incorporated in aerosol cans B65D83/52
• CPC Class Codes: A61M 15/0091 mechanically breath-triggered
• CPC Class Codes: A61M 2202/064 Powder
• CPC Class Codes: A61M 2205/073 Syringe, piston type
• CPC Class Codes: B05B 11/061 characterised by the means producing the gas or vapour pressure
• CPC Class Codes: B05B 11/062 designed for spraying particulate material
• CPC Class Codes: B05B 11/109 the dispensing stroke being affected by the stored energy of a spring B05B11/1088 takes precedence
• CPC Class Codes: B05B 11/1091 being first hold in a loaded state by locking means or the like, then released B05B11/1092 takes precedence

Abstract

A powder jet dispenser for medicament inhalation therapies, intended to be the drug pack container, incorporating a dose metering system, comprising a filling unit (27, 28, 29, 30, 31, 35) and a separation unit (25, 26) to fill a fix positioned dosage chamber (19) and to provide, after filling, air-tight separation of the filling unit from the medicament reservoir (36). The dosage chamber (19) being connected to a compression chamber (5) of a servo-assisted air compression system actuated by a manual stroke of a plunger (3) providing the compression of a spiral load spring (7). The load spring is released through a sliding control mechanism (11, 14) which is automatically actuated by the stroke of the plunger (3). The load spring (7) bears against a piston (8) which, upon release, snaps forward into said compression chamber (5) producing a jet of compressed air which reaches the dosage chamber (19), and passes the drug into the user'"'"'s mouth through a nozzle (20) provided with a check valve (22) to avoid the entrance of external air.

Claims

1. A powder jet dispenser serving as a medicament pack container for medicament inhalation therapies, comprising:

a main body portion(1);

a nozzle (20);

a drug reservoir (36) having a bottom side;

a dosage chamber (19) arranged at the bottom side of said drug reservoir (36); and

a dose metering system, comprising;

filling means for filling said dosage chamber (19), said filling means comprising;

a separation unit (25,

     26) for providing, after the filling of said dosage chamber, an air-tight separation of said filling means from said drug reservoir (36);

an air compression system comprising;

a cylindrical compression chamber (5) formed in a tubular element (13);

a plunger (3), the stroke of said plunger being adapted to actuate said air compression system;

a spiral load spring (7) adapted to accumulate energy by means of its compression;

a sliding control mechanism (11,

     14) adapted to automatically release the accumulated energy of said spiral load spring (7) automatically actuated by the stroke of the plunger (3), wherein said dosage chamber (19) is connected to said compression chamber (5); and

a piston (8), wherein said accumulated energy is released against said piston (8) which is adapted, under the thrust of said load spring (7), to snap forwardly into said compression chamber (5) thereby producing a jet of compressed air delivering the drug from the dosage chamber (19) through said nozzle (20), wherein said filling means is rotatable and said dosage chamber (19) is fixed with respect to said main body portion (1).

2. The powder jet dispenser according to claim 1, wherein said main body portion (1) has upper and lower ends, bearing on its upper end a fixed, screwed cover (2) which closes said drug reservoir (36) and disposed at the lower end said plunger (3) which is axially slidable, hollow, cylindrical and manually actuatable and which is provided with two bores forming a shoulder (4) and a plane bottom bearing a cylindrical base (6) having a seat for supporting and arresting a spiral load main spring (7) assembled in a special blind bore in the piston (8) which is axially slidable in the tubular element (13) forming said cylindrical compression chamber (5) fixed and retained by a distribution and separation head (12), said distribution and separation head (12) being provided with a downwardly protruding neck bearing a secondary return spring (15) resting against a seat formed in a control sleeve (14) which is axially slidable over the tubular element (13), said distribution and separation head (12) being fixed to the upper end of the main tubular body (1) under the drug reservoir chamber (36) which is provided with an air passage chamber (18) containing a sphere check valve (17) in correspondence with a center outlet hole (16) provided at an end of the tubular element (13) in which the piston (8) slides, said air passage chamber (18) being connected by a passage to the stationary dosage chamber (19) having an upper opening connected to the drug reservoir chamber (36) through which it can be filled, and an outlet passage connected to the nozzle (20).

3. A powder jet dispenser according to claim 1, wherein the nozzle (20) is provided with a non-return sphere check valve (22) for forming an air-tight seal.

4. A powder jet dispenser according to claim 1, wherein a head of the piston (8) is provided with a circular seal lip (9).

5. The powder jet dispenser according to claim 1, wherein said tubular element (13) has a slotted groove formed therein, said sliding control mechanism comprises:

a resilient expansible detent ring (11) which is retained in the slotted groove of the tubular element (13);

a circular groove (10) formed on the head of the piston (8); and

a control sleeve (14) having a bore which comprises a cam profile adapted to force said resilient expansible detent ring to protrude inwardly towards the head of the piston (8) and to enter said circular groove (10), said control sleeve being axially slidable over the tubular element (13) to prevent a forward movement of the piston (8) during a loading stroke of the load spring (7) until the control sleeve (14) shifts upwardly releasing the resilient expansible detent ring (11) and allowing the piston (8) to snap forwardly under the thrust of the load spring (7).

6. The powder jet dispenser according to claim 5, wherein said main body portion (1) has upper and lower ends, bearing on its upper end a fixed, screwed cover (2) which closes said drug reservoir (36) and disposed at the lower end said plunger (3) which is axially slidable, hollow, cylindrical and manually actualable and which is provided with two bores forming a shoulder (4) and a plane bottom bearing a cylindrical base (6) having a seat for supporting and arresting a spiral load main spring (7) assembled in a special blind bore in the piston (8) which is axially slidable in the tubular element (13) forming said cylindrical compression chamber (5) fixed and retained by a distribution and separation head (12), said distribution and separation head (12) being provided with a downwardly protruding neck bearing a secondary return spring (15) resting against a seat formed in the control sleeve (14) which is axially slidable over the tubular element (13), said distribution and separation head (12) being fixed to the upper end of the main body portion (1) under the drug reservoir chamber (36) which is provided with an air passage chamber (18) containing a sphere check valve (17) in correspondence with a center outlet hole (16) provided at an end of the tubular element (13) in which the piston (8) slides, said air passage chamber (18) being connected by a passage to the stationary dosage chamber (19) having an upper opening connected to the drug reservoir chamber (36) through which it can be filled, and an outlet passage connected to the nozzle (20).

7. A powder jet dispenser according to claim 1, wherein the dose metering system further comprises:

a turning knob (34) provided with a stem disposed in the drug reservoir, the stem having a square-shaped end;

a cover (2) having a hole and bearing, the turning knob positioned in a sealed manner through a hole; and

a second turning element (27) provided with three arms, wherein two (28) of said three arms each carry a filling brush or broom (29), and the third (30) remaining arm located centrally between said two filling brush or broom carrying arms, carries a softer and longer broom (31), suitable to deeply introduce the powder deeply into the dosage chamber (19) which is formed as a hole in the bottom of the drug reservoir chamber (36) and wherein said separation unit comprises;

an element (25) disposed on the square-shaped end of said turning knob (34), said element (25) provided with vertical faces (35) perpendicular to the bottom side of the drug reservoir;

separation means carried by said element (25) for separating in a sealed manner said dosage chamber (19) from said drug reservoir (36).

8. A powder jet dispenser according to claim 7, wherein the turning knob (34) rotates over a range of 360°

.

9. A powder jet dispenser according to claim 7, wherein said means for separating, upon rotating said turning knob (34) to fill said dosage chamber (19), separates in a sealed manner said dosage chamber (19) from said drug reservoir (36) upon completion of the filling rotation, thereby preventing any compressed air dispersion or drug to return into the drug reservoir (36) during delivery of the drug.

10. A powder jet dispenser serving as medicament pack container for medicament inhalation therapies comprising:

a main body portion (37);

a nozzle (59);

a drug reservoir (36);

a dosage chamber (19) arranged at the bottom of said drug reservoir (36); and

a dose metering system comprising;

filling means adapted to fill said dosage chamber (19), said filling means comprising;

a separation unit (25,

     26) adapted to provide, after the filling of said dosage chamber, an air-tight separation from the drug reservoir (36), said dispenser further comprising;

an air compression system comprising;

a compression cylindrical chamber (5) formed in a tubular element (44);

a plunger (38), the stroke of said plunger being adapted to actuate said air compression system;

a spiral load spring (41) adapted to accumulate energy by means of its compression;

a lever control element (49);

a sliding control mechanism (11,

     45) adapted to automatically release said accumulated energy of said spiral load spring (41), said sliding control mechanism (11,

     45) being automatically actuated by said lever control element (49) directly controlled by a user'"'"'s inhalation, said dosage chamber (19) being connected to said compression chamber (5); and

a piston (42), said accumulated energy being released against said piston (42) which is adapted, under the thrust of said load spring (41), to snap forwardly into said compression chamber (5), thereby producing a jet of compressed air for delivering a drug from the dosage chamber (19) through said nozzle (20,

     59), wherein said filling means is rotatable and said dosage chamber (19) is fixed with respect to said main body portion (37).

11. A powder jet dispenser according to claim 10, wherein the head of the piston (42) is provided with a circular seal lip (9).

12. A powder jet dispenser according to claim 10, wherein said sliding control mechanism comprises:

a resilient expansible detent ring (11) retained in a slotted groove of the tubular element (44);

a groove (10) formed on a head of the piston (42); and

a control sleeve (45) having a bore which comprises a cam profile, said cam profile being adapted to force said resilient expansible detent ring to protrude inwardly towards the head of the piston (42) and to enter said groove (10), said control sleeve being axially slidable over the tubular element (44), thus preventing a forward movement of the piston (42) during the loading stroke of the load spring (41) of the plunger (38) until the control sleeve (45) shifts upwardly releasing the resilient expansible detent ring (11) and allowing the piston (42) to snap forwardly under the thrust of the load spring (41).

13. A powder jet dispenser according to claim 12, wherein one end of the lever control element (49) is associated with a control sleeve (45) through two arms (48), wherein the two arms (48) carry two fulcrum pins (50) which pass through two diametrically opposite slots (46) formed in the control sleeve (45) and enter two blind holes (51) formed in a modified tubular element (44);

each of the fulcrum pins (50) is connected to a cam (47) housed in the slots (46) of the control sleeve (45) and interacts with upper faces (52) of the slots (46); and

another end of the lever control element (49) is formed opposite to the two arms (48) as a semicylindrical vane (53) and placed in a special control chamber (58) formed in said main body portion (37) and is connected by means of suitable passages with a mouthpiece (57) of the dispenser.

14. A powder jet dispenser according to claim 13, wherein the special control chamber (58) which contains the semicylindrical vane (53) of the lever control element (49), is provided with an opening into which is inserted and fixed an air flow conveyer (54) provided with slits (55) for allowing air to enter and with a slit (56) to slidably receive the level control element (49) housing the semicylindrical vane (53);

wherein inhalation by a user creates through the mouthpiece (57) and the special passages in the main body (37) a subatmospheric pressure in the control chamber (58) which causes movement of the semicylindrical vane (53) from its rest position in which it normally closes the slits (55), to a position in which said air can enter, and causing the lever control element (49) to rotate on the fulcrum pins (50) and the associated cams (47), which by interacting with the upper faces (52) of the slots (46) formed on the control sleeve (45) forces the control sleeve (45) to shift allowing the resilient expansible detent ring (11) to expand, thus releasing the piston (42) which snap forwardly, under thrust of the load spring (41) previously loaded by a compression stroke of the plunger (38), producing a jet of compressed air at a predetermined pressure and speed.

15. A powder jet dispenser according to claim 14, wherein the inner surface of the air flow conveyer (54) matches the outer surface of the semicylindrical vane (53) and said conveyer (54) has a depth which is higher than the depth of said vane (53) at such an extent to force the control lever (49) to rotate long enough for delivery of the drug to occur, before air is allowed to enter the control chamber (58).

16. A powder jet dispenser according to claim 10, wherein one end of the lever control element (49) is associated with a control sleeve (45) through two arms (48), wherein the two arms (48) carry two fulcrum pins (50) which pass through two diametrically opposite slots (46) formed in the control sleeve (45) and enter two blind holes (51) formed in a modified tubular element (44);

each of the fulcrum pins (50) is connected to a cam (47) housed in the slots (46) of the control sleeve (45) and interacts with upper faces (52) of the slots (46); and

another end of the lever control element (49) is formed opposite to the two arms (48) as a semicylindrical vane (53) and placed in a special control chamber (58) formed in said main body portion (37) and is connected by means of suitable passages with a mouthpiece (57) of the dispenser.

17. A powder jet dispenser according to claim 16, wherein the special control chamber (58) which contains the semicylindrical vane (53) of the control lever (49), is provided with an opening into which is inserted and fixed an air flow conveyer (54) provided with slits (55) for allowing air to enter and with a slit (56) to slidably receive the control lever (49) housing the semicylindrical vane (53);

wherein inhalation by a user creates through the mouthpiece (57) and the special passages in the main body portion (37) a subatmospheric pressure in the control chamber (58) which causes movement of the semicylindrical vane (53) from its rest position in which it normally closes the slits (55), to a position in which said air can enter, and causing the control lever (49) to rotate on the fulcrum pins (50) and the associated cams (47), which by interacting with the upper faces (52) of the slots (46) formed on the control sleeve (45) forces the control sleeve (45) to shift allowing the resilient expansible detent ring (11) to expand, thus releasing the piston (42) which snap forwardly, under thrust of the load spring (41) previously loaded by a compression stroke of the plunger (38), producing a jet of compressed air at a predetermined pressure and speed.

18. A powder jet dispenser according to claim 17, wherein the inner surface of the air flow conveyer element (54) matches the outer surface of the semicylindrical vane (53) and said conveyer (54) has a depth which is higher than the depth of said vane (53) at such an extent to force the control lever (49) to rotate long enough for delivery of the drug to occur, before air is allowed to enter the control chamber (58).

19. A powder jet dispenser according to claim 10, wherein the dose metering system further comprises:

a turning knob (34) provided with a stem disposed in the drug reservoir, the stem having a square-shaped end;

a cover (2) having a hole and bearing the turning knob positioned in a sealed manner through a hole; and

a second turning element (27) provided with three arms, wherein two (28) of said three arms each carry a filling brush or broom (29), and the third (30) remaining arm located centrally between said two filling brush or broom carrying arms, carries a preferably softer and longer broom (31), suitable to introduce the powder deeply into the dosage chamber (19) which is formed as a hole in the bottom of the drug reservoir chamber (36), and wherein said separation unit comprises;

an element (25) disposed on the square-shaped end of said turning knob (34), said element (25) provided with vertical faces (35) perpendicular to the bottom side of the drug reservoir (36);

separation means carried by said element (25) for separating in a sealed manner said dosage chamber (19) from said drug reservoir (36).

20. A powder jet dispenser according to claim 19, wherein the turning knob (34) rotates over a range of 360°

.

21. A powder jet dispenser according to claim 19, wherein said means for separating, upon rotating said turning knob (34) to fill said dosage chamber (19), separates in a sealed manner said dosage chamber (19) from said drug reservoir (36), upon completion of the filling rotation, preventing any compressed air dispersion or drug to return into the drug reservoir (36) during delivery of the drug.