초록 ▼

A device for delivering a powdered medicament by inhalation comprises an air inlet passage having low pressure-drop and low turbulence for stabilizing air flow before aerosolization, a dosing cup in the region of reduced air velocity to delay aerosolization, a high pressure drop throat to generate a

A device for delivering a powdered medicament by inhalation comprises an air inlet passage having low pressure-drop and low turbulence for stabilizing air flow before aerosolization, a dosing cup in the region of reduced air velocity to delay aerosolization, a high pressure drop throat to generate a high velocity flow, a rapidly expanding diverging passage to create a free jet of air with high turbulence and an outlet passage having large cross-sectional area to control the rate of dissipation of the free jet. The device is simple yet capable of consistently providing uniform and effective powder aerosolization and deagglomeration over a variety of patient inhalation profiles.

대표청구항 ▼

What is claimed is: 1. A device for dispensing powdered medicament by inhalation, comprising an air inlet passage, a transition passage connected to the air inlet passage, said transition passage comprising a holding portion for a dose of powdered medicament and a means for creating a region of red

What is claimed is: 1. A device for dispensing powdered medicament by inhalation, comprising an air inlet passage, a transition passage connected to the air inlet passage, said transition passage comprising a holding portion for a dose of powdered medicament and a means for creating a region of reduced air velocity, a converging passage connected to the transition passage, the converging passage comprising an end that forms a throat, a diverging section connected to the throat, and an air outlet passage connected to the diverging section, wherein the throat, the air inlet passage, the transition passage and the outlet passage each define a cross-sectional area that includes a minimum cross-sectional area, and wherein the cross-sectional area of the throat is smaller than the minimum cross-sectional area of the air inlet passage, the transition passage and the outlet passage, wherein a dose of powdered medicament can be aerosolized from the holding portion by way of an air stream produced by inhalation. 2. A device according to claim 1, wherein the cross-sectional area of the throat is less than 50% of the minimum cross-sectional area of the air inlet passage, the transition passage and the outlet passage. 3. A device according to claim 2, wherein the cross-sectional area of the throat is less than 35% of the minimum cross-sectional area of the air inlet passage, the transition passage and the outlet passage. 4. A device according to claim 1, wherein the cross-sectional area of the outlet passage is larger than the cross-sectional area of the air inlet passage. 5. A device according to claim 1, wherein the cross-sectional area of the outlet passage is larger than three times the cross-sectional area of the throat. 6. A device according to claim 5, wherein the cross-sectional area of the outlet passage is larger than twenty times the cross-sectional area of the throat. 7. A device according to claim 1, wherein the flow Reynolds Number of the air inlet passage is below 5000. 8. A device according to claim 7, wherein the flow Reynolds Number of the air inlet passage is below 4000. 9. A device according to claim 1, wherein the cross-sectional area of the air inlet passage is essentially constant. 10. A device according to claim 1, wherein the diverging section has a divergence angle greater than about 10 degrees. 11. A device according to claim 1, wherein the cross-section of the throat is oval in shape. 12. A device according to claim 1, wherein the length of the air inlet passage is greater than three times the shortest dimension of the air inlet passage. 13. A device according to claim 1, wherein the cross-section of the outlet passage is oval in shape. 14. A device according to claim 1, wherein the transition passage comprises a turn. 15. A device according to claim 14, wherein the transition passage forms a turn which is from about 10 to about 170 degrees. 16. A device according to claim 14, wherein the turn of the transition passage comprises an outer face, and wherein the shape of the holding portion for a dose of powdered medicament is such that it is smoothly integrated into the outer face of the turn of the transition passage. 17. A device according to claim 14, wherein the turn of the transition passage comprises an inner face, and wherein the radius of curvature of the inner face of the turn of the transition passage is greater than 20% of the shortest dimension of the air inlet passage. 18. A device according to claim 14, wherein the cross-sectional area of the transition passage is larger than that of the air inlet passage. 19. A device according to claim 14, wherein the transition passage forms a turn which is from about 45 to about 135 degrees. 20. A device according to claim 14, wherein the transition passage forms a turn which is about 90 degrees. 21. A device according to claim 14, wherein the turn of the transition passage comprises an inner face, and wherein the radius of curvature of the inner face of the turn of the transition passage is about 50% of the shortest dimension of the air inlet passage. 22. A device according to claim 1, wherein the transition passage comprises an expansion. 23. A device according to claim 1, wherein the transition passage comprises a multiple turn. 24. A device according to claim 1, wherein the air inlet passage is smoothly integrated with the transition passage. 25. A device according to claim 1, wherein the holding portion for a dose of powdered medicament is a dosing cup of a metering member adapted to meter a dose of powdered medicament from a medicament reservoir of the device. 26. A device according to claim 1, wherein the transition passage is smoothly integrated with the converging passage. 27. A device according to claim 1, wherein the diverging section forms a dead end zone to minimize backflow. 28. A device according to claim 1, comprising additionally an impactor plate positioned in the outlet passage. 29. A device according to claim 1, wherein the cross-section of the air inlet passage, the transition passage and/or the converging passage is essentially rectangular in shape. 30. A device for dispensing powdered medicament by inhalation, comprising an air inlet passage, a transition passage in the form of a turning passage connected to the air inlet passage, wherein the turning passage comprises an outer wall, a holding portion for a dose of powdered medicament on the outer wall of the turn of the transition passage, a converging passage connected to the transition passage, the converging passage comprising an end that forms a throat, a diverging section connected to the throat, and an air outlet passage connected to the diverging section, wherein the throat, the air inlet passage, the transition passage and the outlet passage each define a cross-sectional area that includes a minimum cross-sectional area, and wherein the cross-sectional area of the throat is smaller than the minimum cross-sectional area of the air inlet passage, the transition passage and the outlet passage, wherein a dose of powdered medicament can be aerosolized from the holding portion by means of an air stream produced by inhalation.