초록

An aerosol generator includes a flow passage having an inlet end, an outlet end, and a constriction in the flow passage at the outlet end. A heater is operable to heat liquid in the flow passage to produce a vapor, which is expelled from the outlet end of the flow passage.

대표청구항 ▼

What is claimed is: 1. An aerosol generator, comprising: a flow passage including an inlet end, an expelling end and a first flow section; a constriction at the expelling end of the flow passage, the constriction defining a second flow section of the flow passage downstream from the first flow sect

What is claimed is: 1. An aerosol generator, comprising: a flow passage including an inlet end, an expelling end and a first flow section; a constriction at the expelling end of the flow passage, the constriction defining a second flow section of the flow passage downstream from the first flow section; and a heater arranged along the flow passage which heats liquid in the first flow section to produce vapor and liquid which is expelled from the outlet expelling end into ambient air; wherein the constriction is adapted to create sufficiently high fluid shear forces to break up droplets of the liquid into smaller droplets. 2. The aerosol generator of claim 1, wherein the first flow section of the flow passage has a first transverse cross-sectional area which is larger than a second transverse cross-sectional area of the second flow section of the flow passage at the expelling end, and the ratio of the first transverse cross-sectional area to the second transverse cross-sectional area is about 2:1 to up to about 30:1. 3. The aerosol generator of claim 1, wherein the flow passage and the constriction are of the same material or of a different material, the material being selected from group consisting of metals, ceramics, glasses, plastics, polymers, and combinations thereof. 4. The aerosol generator of claim 1, wherein the second flow section has a round or a non-round transverse cross-section. 5. The aerosol generator of claim 1, wherein the flow passage and the constriction are of a metallic material. 6. The aerosol generator of claim 1, wherein the first flow section and the second flow section of the flow passage are capillary-sized. 7. The aerosol generator of claim 1, wherein the flow passage has a maximum transverse dimension of from about 0.025 mm to about 0.25 mm. 8. The aerosol generator of claim 1, wherein the flow passage comprises a metallic tube and the constriction is a crimped end of the metallic tube. 9. The aerosol generator of claim 8, wherein the second flow section at the crimped end has a circular or non-circular transverse cross section. 10. The aerosol generator of claim 8, wherein the second flow section has a cross-sectional area of about 500 μm2 about 51,000 μm2. 11. The aerosol generator of claim 8, wherein the crimped end has a length of about 0.5 mm to about 3 mm. 12. The aerosol generator of claim 1, wherein the flow passage comprises multiple pieces including opposed surfaces that are joined together along an interface to define the first and second flow sections therebetween. 13. The aerosol generator of claim 12, wherein the two portions of the flow passage are molded, cast or machined. 14. The aerosol generator of claim 1, wherein the flow passage is capillary-sized and comprises a capillary tube, a monolithic body, or a laminated structure. 15. The aerosol generator of claim 1, wherein the flow passage includes a third flow section near the expelling end of the flow passage, wherein the vapor and liquid is cooled as it is expelled. 16. The aerosol generator of claim 15, wherein the third flow section includes a cooling device in contact with the flow passage and wherein the temperature of the third flow section is reduced by about 10�� C. to about 100�� C. 17. The aerosol generator of claim 16, wherein the temperature of the third flow section is reduced by about 50�� C. to about 70�� C. 18. The aerosol generator of claim 16, wherein the cooling device is a heat sink. 19. The aerosol generator of claim 18, wherein the third flow section is within the first flow section and adjacent to the second flow section. 20. The aerosol generator of claim 1, wherein the constriction has a length of about 3 mm to about 6 mm. 21. The aerosol generator of claim 1, wherein the flow passage is a capillary-sized tube and the constriction is a partial closure of the capillary-sized tube at the expelling end. 22. A handheld aerosol generator, comprising: a flow passage including an inlet end, an expelling end and a first flow section; a constriction at the expelling end of the flow passage, the constriction defining a second flow section of the flow passage downstream from the first flow section; a heater arranged along the flow passage which heats liquid in the first flow section to produce a vapor and liquid which is expelled from the expelling end; and a mouthpiece in fluid communication with the expelling end of the flow passage through which a user can draw aerosol from the aerosol generator; wherein the constriction is adapted to create sufficiently high fluid shear forces to break up droplets of the liquid into smaller droplets. 23. The aerosol generator of claim 22, wherein the flow passage includes a third flow section near the expelling end of the flow passage, wherein the vapor is cooled as it is expelled, and wherein the third flow section includes a cooling device in contact with the flow passage and wherein the temperature of the third flow section is reduced by about 10�� C. to about 100�� C. 24. The aerosol generator of claim 23, wherein the temperature of the third flow section is reduced by about 50�� C. to about 70�� C. 25. The aerosol generator of claim 23, wherein the cooling device is a heat sink. 26. An aerosol generator, comprising: a flow passage including an inlet end, an expelling end and a first flow section; a constriction at the expelling end of the flow passage, the constriction defining a second flow section of the flow passage downstream from the first flow section; a liquid source in flow communication with the inlet end of the flow passage, the liquid source containing a liquid formulation including a medicament; and a heater arranged along the flow passage which heats the liquid formulation in the first flow section to produce a vapor and liquid which is expelled from the expelling end so as to form an aerosol; wherein the constriction is adapted to create sufficiently high fluid shear forces to break up droplets of the liquid into smaller droplets. 27. The aerosol generator of claim 26, wherein the liquid source contains a liquid comprising at least one medicament selected from the group consisting of insulin, buprenorphine hydrochloride, cromolyn sodium, albuterol sulfate, isoproterenol sulfate, metaproterenol sulfate, terbutaline sulfate, pirbuterol acetate, salmeterol xinotoate, formotorol, beclomethasone dipropionate, flunisolide, fluticasone, budesonide, triamcinolone acetonide, beclomethasone dipropionate, triamcinolone acetonide, flunisolide and fluticasone. 28. The aerosol generator of claim 26, wherein the liquid source contains a medicament selected from the group consisting of analgesics, anginal preparations, anti-allergics, antibiotics, antihistamines, antitussives, bronchodilators, diuretics, anticholinergics, hormones and anti-flammatory agents. 29. The aerosol generator of claim 26, wherein the liquid source contains a single dose or multiple doses of the medicament. 30. The aerosol generator of claim 26, wherein the liquid formulation comprises a medicament, a highly-volatile carrier and optionally a low-volatility carrier. 31. The aerosol generator of claim 30, wherein the highly-volatile carrier comprises (i) about 20-80 volume % water and about 80-20 volume % ethanol or (ii) about 80-100 volume % water and up to about 20 volume % ethanol. 32. The aerosol generator of claim 26, further comprising: a power supply; a valve disposed between the liquid source and the flow passage; and a controller operable to actuate the valve to control flow of the liquid from the liquid source to the inlet end of the flow passage and to control the delivery of power from the power supply to the heater to maintain the heater at a temperature range effective to vaporize liquid in the flow passage. 33. The aerosol generator of claim 26, wherein the liquid source is removably attachable to the aerosol generator. 34. The aerosol generator of claim 26, wherein the flow passage includes a third flow section near the expelling end of the flow passage, wherein the vapor and liquid is cooled as it is expelled, and wherein the third flow section includes a cooling device in contact with the flow passage and wherein the temperature of the flow passage expelling end is reduced by about 10�� C. to about 100�� C. 35. The aerosol generator of claim 34, wherein the temperature of the third flow section is reduced by about 50�� C. to about 70�� C. 36. The aerosol generator of claim 34, wherein the cooling device is a heat sink. 37. The aerosol generator of claim 34, wherein the third flow section is within the first flow section and adjacent to the second flow section. 38. An aerosol generator, comprising: a flow passage including an inlet end, an expelling end and a first flow section; a constriction at the expelling end of the flow passage, the constriction defining a second flow section of the flow passage downstream from the first flow section; a heater arranged along the flow passage; a power supply adapted to supply power to the heater; and a controller controlling operation of the power supply to supply an effective amount of power to the heater to heat liquid in the first flow section to produce a vapor and liquid which is expelled from the expelling end; wherein the constriction is adapted to create sufficiently high fluid shear forces to break up droplets of the liquid into smaller droplets. 39. The aerosol generator of claim 38, wherein the flow passage includes a third flow section near the expelling end of the flow passage, wherein the vapor and liquid is cooled as it is expelled, and wherein the third flow section includes a cooling device in contact with the flow passage and wherein the temperature of the flow passage expelling end is reduced by about 10�� C. to about 100�� C. 40. An aerosol generator, comprising: a flow passage including an inlet end, an expelling end and a first flow section; a constriction at the expelling end of the flow passage, the constriction defining a second flow section of the flow passage downstream from the first flow section; and a heater arranged along the flow passage which heats liquid in the first flow section to produce vapor and liquid which is expelled from the expelling end so as to form an aerosol, a first electrode attached to the heater and a second electrode attached to the heater downstream of the first electrode, the second electrode being of a material that has a smaller resistance than a material of the heater; wherein the constriction is adapted to create sufficiently high fluid shear forces to break up droplets of the liquid into smaller droplets. 41. The aerosol generator of claim 40, wherein the flow passage is of stainless steel and the second electrode is of a Cu--Be alloy. 42. A method of producing an aerosol, comprising: supplying a liquid to the inlet end of a flow passage including an expelling end, a first flow section and a constriction at the expelling end, the constriction defining a second flow section of the flow passage downstream from the first flow section; and heating the liquid in the first flow section to produce vapor and liquid which is expelled from the expelling end into ambient air; wherein the constriction is adapted to create sufficiently high fluid shear forces to break up droplets of the liquid into smaller droplets. 43. The method of claim 42, wherein only a portion of the liquid in the first flow section is vaporized by heating. 44. The method of claim 42, wherein the heating includes applying a power level that is less than a theoretical power level for vaporizing 100 % of the liquid to a heater to heat the liquid in the first flow section. 45. The method of claim 42, wherein the liquid comprises at least one medicament selected from the group consisting of insulin, buprenorphine hydrochloride, cromolyn sodium, albuterol sulfate, isoproterenol sulfate, metaproterenol sulfate, terbutaline sulfate, pirbuterol acetate, salmeterol xinotoate, formotorol, beclomethasone dipropionate, flunisolide, fluticasone, budesonide, triamcinolone acetonide, beclomethasone dipropionate, triamcinolone acetonide, flunisolide and fluticasone. 46. The method of claim 42, wherein the liquid contains a medicament selected from the group consisting of analgesics, anginal preparations, anti-allergics, antibiotics, antihistamines, antitussives, bronchodilators, diuretics, anticholinergics, hormones and anti-flammatory agents. 47. The method of claim 46, wherein the liquid comprises a medicament and a highly-volatile carrier. 48. The method of claim 47, wherein the highly-volatile carrier is selected from the group consisting of water, ethanol and mixtures thereof. 49. The method of claim 42, wherein the liquid comprises a high-volatility carrier and insulin. 50. The method of claim 42, including producing the aerosol with a handheld inhaler. 51. The method of claim 42, including: supplying power to the heater with a power supply; and controlling operation of the power supply with a controller to supply an effective amount of power to the heater to heat the liquid formulation in the first flow section to produce a vapor and liquid which is expelled from the expelling end. 52. The method of claim 42, further comprising cooling the vapor in a third flow section as it is expelled, wherein the third flow section is in a downstream portion of the first flow section and includes a cooling device in contact with the flow passage, and wherein the temperature of the temperature of the third flow section is reduced by about 10�� C. to about 100�� C.