Gas venting device and a system and method for venting a gas from a liquid delivery system

• US 20040025693A1
• Filed: 08/08/2002
• Published: 02/12/2004
• Est. Priority Date: 08/08/2002
• Status: Active Grant

• Current Assignee: Baxter Healthcare SA (Baxter International Inc.), Baxter International Inc.
• Original Assignee: Baxter International Inc.
• Inventors: Parish, John A., Pan, Li, Bedingfield, John
• Granted Patent: US 6,746,514 B2
• Time in Patent Office: Days
• US Class Current: 95/273
• CPC Class Codes: A61M 1/3627 Degassing devices; Buffer reservoirs; Drip chambers; Blood filters
• CPC Class Codes: A61M 2005/3123 having air entrapping or venting means, e.g. purging channels in pistons
• CPC Class Codes: B01D 19/0031 by filtration

Abstract

An apparatus, a system and a method for venting a gas from a liquid delivery system are provided. A venting tube may be provided and may be positioned within a chamber that contains the liquid. The liquid may have a top surface within the chamber. The venting tube may have an opening covered by a liquiphobic membrane or a hydrophobic membrane. The membrane may define a plane or a surface which is not parallel to the top surface of the liquid. Gas may pass through a portion of the membrane into the venting tube. Moreover, the membrane may vent the gas. The membrane is non-parallel to the liquid, and, as a result, the membrane may be less prone to clogging.

Claims

1. A method for venting a gas from a liquid delivery system, the method comprising the steps of:

holding a liquid having a surface within a chamber having an interior wherein a portion of the chamber extends into the interior wherein the portion which extends into the interior forms a non-parallel surface to the surface of the liquid and further has a hole; and

attaching a liquiphobic membrane to the portion of the chamber which extends towards the interior wherein the membrane is within the interior of the chamber and further wherein the liquiphobic membrane covers the hole.

2. The method of claim 1 further comprising the step of:

adding liquid to the interior of the chamber.

3. The method of claim 1 further comprising the step of:

removing the gas from the chamber.

4. The method of claim 1 further comprising the step of:

venting the gas through the hole in the portion of the chamber which extends towards the interior of the chamber.

5. The method of claim 1 wherein the liquiphobic membrane conforms to the shape of the non-parallel surface.

6. The method of claim 1 wherein the non-parallel surface is non-planar.

7. A method for venting a gas from a liquid delivery system, the method comprising the steps of:

providing a tube having walls defining an interior wherein the tube has an opening;

attaching a gas-permeable membrane to the tube wherein the membrane covers the opening; and

placing the tube to extend within a chamber having walls defining an interior wherein the chamber holds the liquid having a top surface within the chamber and further wherein the membrane defines a surface that is not parallel to the top surface of the liquid.

8. The method of claim 7 further comprising the step of:

adding liquid in the interior of the chamber.

9. The method of claim 7 further comprising the step of:

venting gas through the tube wherein the gas exits the tube exterior to the interior of the chamber.

10. The method of claim 7 further comprising the step of:

venting gas through holes in the walls of the tube exterior to the interior of the tube.

11. The method of claim 7 further comprising the step of:

providing a second opening in the tube wherein the second opening is covered by the membrane.

12. An apparatus for venting a gas from a liquid delivery system, the apparatus comprising:

a tube having an interior defined by walls having a length defined between a first end and a second end wherein the tube has a top surface at the first end wherein the top surface defines a plane;

an opening at the second end of the tube wherein the opening defines a plane wherein the plane of the opening is not parallel to the plane of the top surface; and

a membrane covering the opening of the tube wherein the membrane prevents the liquid from passing through the membrane and allows the gas to enter into the interior of the tube through the opening of the tube.

13. The apparatus of claim 12 further comprising:

a venting hole in the walls of the tube.

14. The apparatus of claim 12 wherein the plane defined by the opening is perpendicular to the plane defined by the top surface.

15. The apparatus of claim 12 wherein the walls of the tube form an apex at the second end.

16. The apparatus of claim 12 further comprising:

a second opening in the walls of the tube wherein the membrane covers the second opening.

17. The apparatus of claim 12 wherein the membrane is attached to the venting tube at a point on the wall between the top surface and the opening.

18. The apparatus of claim 12 wherein the walls of the tube at the second end are rounded.

19. A system for venting a gas from a liquid delivery system, the system comprising:

a first tube having walls defining an interior wherein the first tube has a first opening;

a chamber having walls defining an interior with an opening in one of the walls wherein the interior holds the liquid wherein the liquid has a top surface and further wherein the first tube extends into the interior of the chamber through the opening; and

a membrane covering the first opening of the first tube wherein the membrane is gas-permeable and defines a surface that is not parallel to the top surface of the liquid.

20. The system of claim 19 further comprising:

a gas pocket within the interior of the chamber defined by a volume of the interior which does not contain the liquid.

21. The system of claim 19 further comprising:

a venting hole in the wall of the first tube wherein the venting hole is exterior to the walls of the chamber.

22. The system of claim 19 further comprising:

a liquid input port in one of the walls of the chamber.

23. The system of claim 19 further comprising:

a liquid exit port in one of the walls of the chamber.

24. The system of claim 19 further comprising:

a second opening in the walls of the first tube wherein the membrane covers the second opening.

25. The system of claim 19 wherein the walls of the first tube form an apex.

26. The system of claim 19 further comprising:

a second tube within the interior of the chamber wherein the second tube is attached to a weight.

27. An apparatus for venting a gas from a liquid delivery system, the apparatus comprising:

a chamber having a body defining an interior holding a liquid wherein the chamber traps gas within the interior;

a depression integrally formed with the body wherein the depression has an inside surface within the interior of the chamber wherein the liquid within the interior of the chamber has a surface defining a plane;

an input port on the chamber wherein the input port allows entry of the liquid into the chamber;

an exit port on the chamber wherein the liquid within the chamber exits the chamber through the exit port; and

a liquiphobic membrane positioned on the inside surface of the depression wherein the liquiphobic membrane defines a surface which is non-parallel to the plane defined by the surface of the liquid within the chamber.

28. The apparatus of claim 27 wherein the membrane is attached to the inside surface of the depression.

29. The apparatus of claim 27 further comprising:

a hole in the depression wherein the membrane covers the hole.

30. The apparatus of claim 27 wherein the input port is below the surface of the liquid.

31. The apparatus of claim 27 wherein the exit port is below the surface of the liquid.