Gas Generation Dispenser Apparatus and Method for On-Demand Fluid Delivery

• US 20080257915A1
• Filed: 10/24/2007
• Published: 10/23/2008
• Est. Priority Date: 04/18/2007
• Status: Active Grant

• Current Assignee: Microlin LLC
• Original Assignee: Microlin LLC
• Inventors: Wold, Truman
• Granted Patent: US 8,113,390 B2
• Time in Patent Office: Days
• US Class Current: 222/389
• CPC Class Codes: A61L 2209/132 Piezo or ultrasonic elements for dispensing
• CPC Class Codes: A61L 9/12 Apparatus, e.g. holders, therefor
• CPC Class Codes: A61M 11/007 Syringe-type or piston-type sprayers or atomisers
• CPC Class Codes: A61M 2005/14204 with gas-producing electrochemical cell
• CPC Class Codes: A61M 2005/14513 with secondary fluid driving or regulating the infusion
• CPC Class Codes: A61M 2205/3368 Temperature
• CPC Class Codes: A61M 2205/8206 battery-operated
• CPC Class Codes: A61M 2205/8231 using electrochemical gas generating device for the driving gas
• CPC Class Codes: A61M 5/14244 adapted to be carried by the patient, e.g. portable on the body
• CPC Class Codes: A61M 5/14526 the piston being actuated by fluid pressure
• CPC Class Codes: B05B 11/025 with stepwise advancement of the piston, e.g. for spraying a predetermined quantity of content
• CPC Class Codes: B05B 11/04 Deformable containers producing the flow, e.g. squeeze bottles
• CPC Class Codes: B05B 11/061 characterised by the means producing the gas or vapour pressure

Abstract

An on-demand fluid dispenser to dispense fluid in response to gas generation by a gas cell. The on-demand fluid dispenser includes an expandable gas chamber, a fluid chamber, and an on-demand gas cell. The expandable gas chamber includes a moveable plunger forming a wall of the expandable gas chamber. The moveable plunger also forms a wall of the fluid chamber. The on-demand gas cell is configured to generate the gas on demand. The on-demand gas cell is also configured to direct the gas to the expandable gas chamber to expand the expandable gas chamber. Expansion of the expandable gas chamber moves the moveable plunger to reduce a volume of the fluid chamber and to dispense an amount of fluid from the fluid chamber.

Claims

1. A method of dispensing a fluid comprising:

generating a gas from a liquid;

directing the gas to an expandable gas chamber to expand a volume of the expandable gas chamber;

reducing a volume of a fluid chamber in response to expansion of the expandable gas chamber to dispense an amount of the fluid from the fluid chamber; and

removing the gas from the expandable gas chamber to collapse the expandable gas chamber.

2. The method of claim 1, further comprising collapsing the expandable gas chamber while substantially maintaining the volume of the fluid chamber.

3. The method of claim 1, wherein generating the gas comprises generating the gas at a gas generation rate that is higher than a gas removal rate associated with removing the gas from the expandable gas chamber.

4. The method of claim 1, wherein removing the gas comprises:

converting the gas back into the liquid; and

storing the liquid in a liquid storage reserve.

5. The method of claim 4, wherein converting the gas back into the liquid comprises inducing an electrochemical reaction of chemical components within the gas.

6. The method of claim 1, wherein generating the gas comprises generating a volume of gas in a first range from about one to one hundred microliters for a single delivery of fluid from the fluid chamber.

7. The method of claim 6, further comprising generating the volume of gas in less than approximately five seconds.

8. The method of claim 1, further comprising generating the gas to dispense the fluid on demand in response to a user input.

9. An on-demand fluid dispenser comprising:

an expandable gas chamber comprising a moveable plunger forming a wall of the expandable gas chamber;

a fluid chamber, wherein the moveable plunger forms a wall of the fluid chamber; and

an on-demand gas cell to generate the gas on demand and to direct the gas to the expandable gas chamber to expand the expandable gas chamber, wherein expansion of the expandable gas chamber moves the moveable plunger to reduce a volume of the fluid chamber and to dispense an amount of fluid from the fluid chamber.

10. The on-demand fluid dispenser of claim 9, further comprising:

a power source connected to the gas cell; and

a switch coupled to the power source, the switch configured to activate the gas cell, wherein the gas cell is configured to produce a volume of displacement gas in a range from about twenty to fifty microliters in approximately three seconds.

11. The on-demand fluid dispenser of claim 9, further comprising a gas permeable element forming at least a portion of a wall of the expandable gas chamber, wherein the gas permeates out of the expandable gas chamber through the gas permeable element.

12. The on-demand fluid dispenser of claim 9, further comprising a solenoid valve coupled to a wall of the expandable gas chamber, wherein the solenoid valve is configured to open to release the gas from the expandable gas chamber in response to the amount of fluid dispensed from the fluid chamber.

13. The on-demand fluid dispenser of claim 9, further comprising a pump coupled to the expandable gas chamber, wherein the pump is configured to pump the gas out of the expandable gas chamber and to create a vacuum within the expandable gas chamber to collapse the expandable gas chamber.

14. The on-demand fluid dispenser of claim 9, further comprising a resilient member connected to a second moveable wall of the expandable gas chamber, wherein the resilient member is configured to move the second moveable wall in a single direction along a substantially linear path to collapse the expandable gas chamber in response to the amount of fluid dispensed from the fluid chamber.

15. The on-demand fluid dispenser of claim 9, wherein the plunger is a first movable wall, the on-demand fluid dispenser further comprising:

a second movable wall; and

at least a first magnetic element on the first movable wall and a second magnetic element on the second movable wall;

wherein the first and second magnetic elements exert an attractive force on each other.

16. The on-demand fluid dispenser of claim 9, wherein the moveable plunger is constrained to move in a single direction along a substantially linear path to reduce the volume of the fluid chamber.

17. The on-demand fluid dispenser of claim 16, further comprising:

an outlet coupled to the fluid chamber to dispense the amount of fluid from the fluid chamber; and

a valve within the outlet to inhibit a flow of the fluid back into the fluid chamber.

18. The on-demand fluid dispenser of claim 16, further comprising a second moveable structure forming a second wall of the expandable gas chamber, wherein removal of the gas from the expandable gas chamber moves the second moveable structure to collapse the expandable gas chamber.

19. The on-demand fluid dispenser of claim 18, wherein the second moveable structure is constrained to move in a single direction along a substantially linear path to collapse the expandable gas chamber.

20. The on-demand fluid dispenser of claim 9, further comprising an electrochemical liquid generator to convert the gas in the expandable gas chamber back into a liquid in response to the amount of fluid dispensed from the fluid chamber.

21. An on-demand fluid dispenser comprising:

means for expanding an expandable gas chamber on demand in response to a fluid release signal;

means for dispensing fluid from a fluid chamber in response to expansion of the expandable gas chamber; and

means for regulating a substantially consistent output of the fluid from the fluid chamber over a variety of environmental conditions.

22. The on-demand fluid dispenser of claim 21, further comprising means for moving at least a portion of the expandable gas chamber in a single direction under control of a gas in the expandable gas chamber.

23. The on-demand fluid dispenser of claim 22, further comprising means for preventing movement of the moveable plunger in an opposite direction toward the expandable gas chamber.

24. The on-demand fluid dispenser of claim 22, further comprising means for moving a second moveable structure forming a second wall of the expandable gas chamber toward the fluid chamber.

25. The on-demand fluid dispenser of claim 24, further comprising means for releasing the gas from the expandable gas chamber.