Device for reducing the relative humidity of a flowing gas

• US 5,634,517 A
• Filed: 01/24/1995
• Issued: 06/03/1997
• Est. Priority Date: 01/27/1994
• Status: Expired due to Fees

• Current Assignee: Maquet Critical Care AB (Getinge AB)
• Original Assignee: Siemens-Elema AB (Siemens AG)
• Inventors: Schnuerer, Magnus, Linden, Dan
• Primary Examiner(s): Leo, Leonard R.
• Application Number:
  US08/377,262
• Time in Patent Office: 861 Days
• Field of Search: 165/142, 165/111, 128/205.12, 128/204.16, 604/319, 55/267, 95/290
• US Class Current: 165/111
• CPC Class Codes: A61B 5/097 Devices for facilitating collection of breath or for directing breath into or through measuring devices
• CPC Class Codes: B01D 5/0012 Vertical tubes
• CPC Class Codes: F28D 7/12 the surrounding tube being closed at one end, e.g. return type F28D7/14 takes precedence

Abstract

A passive device for reducing the relative humidity of a flowing gas has a container in which a tube is disposed. A flowing gas passes into the-container-through a inlet and then flows downwardly through a cavity in the container, whereupon the gas transfers heat to the tube and the walls of the container. As a result, liquid water condenses from the water vapor content of the gas. The flowing gas then flows upwardly through a channel in the tube and is then warmed by the heat previously transferred to the tube, whereupon the relative humidity of the flowing gas decreases.

Claims

1. A device for reducing the relative humidity of a flowing gas, said flowing gas having a temperature warmer than ambient atmosphere in which said device is disposed, said device comprising:

a container having a top end and a bottom end with a cavity with an interior wall therebetween, and an inlet for flowing gas containing water vapor disposed at said top end;

an element consisting of heat conducting material having a through-channel therein disposed in said cavity of said container, said through-channel of said element having an opening disposed in said cavity spaced from said bottom end of said container, and having an opening forming an outlet for said flowing gas disposed at said top end of said container, said container and said element forming, in combination, means for dehumidifying and reducing the temperature of said flowing gas entering said container through said inlet by heat exchange between said flowing gas and an upper portion of said element for producing cooler flowing gas and thereby warming said upper portion of said element as said cooler flowing gas flows in a flow path from said top end of said container through said cavity to said bottom end of said container and into said through-channel and by condensing water, in said flow path, from said cooler flowing gas on said interior wall of said cavity, and by re-heating said cooler flowing gas exiting said container through the warmed upper portion of said through-channel and said outlet; and

means for thermally insulating said element from said container.

2. A device as claimed in claim 1 wherein said element comprises a thin-walled tube.

3. A device as claimed in claim 1 wherein said container comprises a thin-walled container consisting of a heat-conducting material.

4. A device as claimed in claim 1 wherein said element has an exterior surface and carries means on said exterior surface for enlarging the area of said exterior surface.

5. A device as claimed in claim 4 wherein said means for enlarging the area of said exterior surface of said element comprises a plurality of projections extending from said element toward said container.

6. A device as claimed in claim 1 wherein said container has an exterior surface and carries means on said exterior surface for enlarging the area of said exterior surface.

7. A device as claimed in claim 6 wherein said means for enlarging the area of said exterior surface of said container comprises a plurality of projections extending from said exterior surface.

8. A device as claimed in claim 1 wherein said cavity has a cylindrical shape.

9. A device as claimed in claim 1 wherein said element and said through-channel each have a cylindrical shape.

10. A device as claimed in claim 9 wherein said element has an exterior with a screw-like flange thereon extending along a longitudinal length of said element and facing said container.

11. A device as claimed in claim 1 wherein said container has a tap hole at said bottom end, and said device further comprising a collection vessel detachably connected to an exterior of said container at said bottom end of said container for collecting liquid, condensed from said flowing gas, through said tap hole.

12. A device as claimed in claim 1 wherein said element comprises a further through-channel disposed in said cavity and communicating with said outlet.

13. A device as claimed in claim 1 further comprising a further element disposed in said cavity, said further element having a through-channel therein and said through-channel in said further element communicating with said outlet.

14. A device as claimed in claim 1 wherein said element comprises a plurality of longitudinally joined segments and means disposed between each segment for thermally separating adjacent segments.