Dispensing method and system of a capillary aerosol generator

• US 20090084865A1
• Filed: 10/01/2008
• Published: 04/02/2009
• Est. Priority Date: 10/02/2007
• Status: Abandoned Application

• Current Assignee: Philip Morris USA Incorporated (Altria Group, Inc.)
• Original Assignee: Philip Morris USA Incorporated (Altria Group, Inc.)
• Inventors: Maharajh, Niranjan
• Application Number:
  US12/285,314
• Publication Number:
  US 20090084865A1
• Time in Patent Office: Days
• US Class Current: 239/1
• CPC Class Codes: A61M 11/007 Syringe-type or piston-type sprayers or atomisers
• CPC Class Codes: A61M 11/041 using heaters
• CPC Class Codes: A61M 11/042 electrical
• CPC Class Codes: A61M 15/002 with air flow regulating means
• CPC Class Codes: A61M 15/025 Bubble jet droplet ejection devices
• CPC Class Codes: A61M 16/20 Valves specially adapted to medical respiratory devices
• CPC Class Codes: A61M 2205/3331 Pressure; Flow
• CPC Class Codes: A61M 2205/3334 Measuring or controlling the flow rate
• CPC Class Codes: B05B 15/52 for removal of clogging particles
• CPC Class Codes: B08B 9/0326 Using pulsations
• CPC Class Codes: Y10T 137/0419 Fluid cleaning or flushing

Abstract

A method of dispensing a liquid or aerosol to maintain a clog free capillary system, which includes supplying a liquid formulation from a pumping unit to a capillary of an aerosol generation unit at a flow rate, and periodically increasing the flow rate from a first flow rate to a second flow rate.

Claims

1. A method of dispensing a liquid or aerosol to maintain a clog free capillary system, comprising:

supplying a liquid formulation from a pumping unit to a capillary of an aerosol generation unit at a flow rate; and

periodically increasing the flow rate from a first flow rate to a second flow rate.

2. The method of claim 1, further comprising vaporizing at least a portion of the liquid formulation within the capillary of the aerosol generation unit.

3. The method of claim 1, wherein the second flow rate is at least twice the first flow rate.

4. The method of claim 1, wherein the pumping unit includes a valving arrangement operable to supply the liquid formulation into an inlet of one syringe pump during delivery of liquid formulation to the aerosol generator unit by another syringe pump, and wherein increasing the flow rate from the first flow rate to the second flow rate is performed at least once per each syringe cycle.

5. The method of claim 1, wherein the system has an operating pressure, and wherein periodically increasing the first flow rate to the second flow rate increases the operating pressure within the system.

6. The method of claim 1, further comprising increasing the first flow rate to the second flow rate for less than one second at a frequency of one burst every 10 seconds or less.

7. The method of claim 1, further comprising increasing the frequency of increased flow rate for liquid formulations having a higher concentration.

8. The method of claim 1, further comprising adjusting the timing of the periodic increases in the flow rate depending on the liquid formulation, the first flow rate and the desired aerosolization parameters.

9. The method of claim 1, wherein the capillary system is a drug delivery system.

10. A method of dispensing a liquid formulation in a drug delivery system to an aerosol generation unit, comprising:

supplying a liquid formulation from a pumping unit to a capillary of an aerosol generation unit at a flow rate, the pumping unit having two syringe pumps and a valving arrangement operable to supply the liquid formulation into an inlet of one syringe pump during delivery of liquid formulation to the aerosol generator unit by the other syringe pump;

vaporizing at least a portion of the liquid formulation within the capillary of the aerosol generation unit; and

increasing the flow rate from a first flow rate to a second flow rate at least once per each syringe cycle.

11. The method of claim 10, wherein the capillary has an operating pressure and increasing the flow rate increases the operating pressure within the capillary.

12. The method of claim 10, wherein the second flow rate is at least twice the first flow rate.

13. The method of claim 10, wherein increasing the flow rate is performed in a plurality of short bursts, wherein each of the plurality of short bursts occurs for less than one second at a frequency of one burst every 10 seconds or less.

14. The method of claim 10, wherein timing of the increases in the flow rate is dependent on the liquid formulation, the flow rate and the desired aerosolization parameters.

15. The method of claim 10, wherein increasing the flow rate results in an increase in operating pressure within the system.

16. A system for maintaining a clog free capillary comprising:

an aerosol generation unit having a capillary passage;

a liquid formulation;

a pumping unit, which supplies the liquid formulation to the aerosol generation unit at a flow rate, wherein at least a portion of the liquid formulation is vaporized within the capillary of the aerosol generation unit; and

a controller, which operates the pumping unit to provide for periodic increases in the flow rate for clog prevention.

17. The system of claim 16, wherein the periodic increases in flow rate further comprises periodically increasing the flow rate from a first flow rate to a second flow rate, and wherein the second flow rate is at least twice the first flow rate.

18. The system of claim 16, wherein the pumping unit has a pair of syringe pumps, and wherein the pumping unit includes a valving arrangement operable to supply the liquid formulation into an inlet of a syringe pump during delivery of the liquid formulation to the aerosol generator unit by the other syringe pump, and wherein increasing the flow rate from the first flow rate to the second flow rate is performed at least once per each syringe cycle.

19. The system of claim 16, further comprising increasing the first flow rate to the second flow rate for less than one second at a frequency of one burst every 10 seconds or less.

20. The system of claim 16, further comprising adjusting the timing of the periodic increases in the flow rate depending on the liquid formulation, the first flow rate and the desired aerosolization parameters.

21. A method of dispensing a fluid from a fluid source, comprising:

supplying a fluid to a pumping unit having a first syringe pump and a second syringe pump, each syringe pump having an aspirating valve and a discharge valve;

discharging the fluid from the first syringe pump by closing the aspirating valve and opening the discharge valve; and

aspirating the second syringe pump by opening the aspirating valve and closing the discharge valve to draw the fluid into the second syringe pump.

22. The method of claim 21, wherein aspirating the second syringe pump is completed before the first syringe pump completes discharging the fluid from the first syringe pump.

23. The method of claim 21, further comprising:

discharging the fluid from the second syringe pump by closing the aspirating valve and opening the discharge valve; and

aspirating the first syringe pump by opening the aspirating valve and closing the discharge valve to draw the fluid into the first syringe pump.

24. The method of claim 23, wherein aspirating the first syringe pump is completed before the second syringe pump completes discharging the fluid from the second syringe pump.

25. The method of claim 23, further comprising periodically discharging the first and second syringe pumps simultaneously.