Apparatus for withdrawal of liquid from a container and method

• US 6,012,453 A
• Filed: 10/15/1997
• Issued: 01/11/2000
• Est. Priority Date: 04/20/1995
• Status: Expired due to Term

• Current Assignee: Scott Technologies, Inc. (3M Company)
• Original Assignee: Figgie International, Inc. (Johnson Controls International plc)
• Inventors: Hynek, Scott J., Tsals, Izrail, Frustaci, Dominick J.
• Primary Examiner(s): Lewis, Aaron J.
• Assistant Examiner(s): MARTIN, TOOD M
• Application Number:
  US08/951,138
• Time in Patent Office: 818 Days
• Field of Search: 128/201.21, 128/200.24, 128/913, 62/50.1
• US Class Current: 128/201.21
• CPC Class Codes: A62B 7/02 with compressed oxygen or air
• CPC Class Codes: A62B 7/06 with liquid oxygen or air; Cryogenic systems
• CPC Class Codes: B63C 2011/2263 using breathing gas stored in its liquid phase, e.g. cryogenic breathing gas
• CPC Class Codes: F17C 2201/0109 with exteriorly curved end-piece
• CPC Class Codes: F17C 2201/056 Small (<1 m3)
• CPC Class Codes: F17C 2203/0391 by vacuum
• CPC Class Codes: F17C 2205/013 Two or more vessels
• CPC Class Codes: F17C 2205/0332 Safety valves or pressure relief valves
• CPC Class Codes: F17C 2205/0338 Pressure regulators
• CPC Class Codes: F17C 2205/0385 in blocks or units
• CPC Class Codes: F17C 2205/0391 inside the pressure vessel
• CPC Class Codes: F17C 2205/0397 on both sides of the pressure vessel
• CPC Class Codes: F17C 2221/011 Oxygen
• CPC Class Codes: F17C 2221/014 Nitrogen
• CPC Class Codes: F17C 2223/0161 cryogenic, e.g. LNG, GNL, PLNG
• CPC Class Codes: F17C 2223/033 Small pressure, e.g. for liquefied gas
• CPC Class Codes: F17C 2223/047 with a dip tube
• CPC Class Codes: F17C 2227/0302 by heating
• CPC Class Codes: F17C 2250/0413 with floats
• CPC Class Codes: F17C 2270/025 Breathing
• CPC Class Codes: F17C 2270/0509 : "Dewar" vessels
• CPC Class Codes: F17C 7/04 : with change of state, e.g. vaporisation
• CPC Class Codes: F17C 9/02 : with change of state, e.g. vaporisation
• CPC Class Codes: Y10S 128/913 : Breathable liquids

Abstract

An apparatus that provides for withdrawal of the liquid contents from a closed container 14 independent of the spatial orientation thereof, is described. The liquid withdrawal apparatus includes flexible withdrawal conduits 58 disposed inside the container and in fluid flow communication with external heat exchangers 144, 146. The heat exchangers serve to transfer heat to the withdrawn liquid to thereby provide a breathable gas mixture. The upstream end of the withdrawal conduits 58 are provided with a weighted pick-up means comprising a wicking material that draws liquid into the interior thereof to ensure contact of the liquid with the conduits, even when the supply of liquid is nearly depleted. A pressure differential between the inside of the container and the external heat exchangers, normally brought about by an inhalation event of the user, provides the motive force for withdrawing the liquid contents from the container through the conduits.

Claims

1. An assembly for withdrawing a liquid from a closed container, the assembly comprising:

a) a conduit comprising an upstream open end disposed inside the container and an opposed downstream open end located outside the container, wherein at least a portion of the conduit is of a flexible material such that the conduit reaches all of an enclosed volume of the container intended to contain the liquid upon changes in the orientation of the container while maintaining free and open flow therethrough;

b) a pick-up provided at the upstream open end of the conduit, wherein the pick-up comprises an enclosing side wall surrounding the upstream open end of the conduit disposed therein;

c) a wicking material housed inside the pick-up in a substantially surrounding relationship with the upstream open end of the conduit, wherein the enclosing side wall of the pick-up is provided with at least one perforation for enabling the wicking material to draw the liquid into the pick-up to thereby maintain the upstream open end of the conduit in contact with the liquid upon changes in the orientation of the container; and

d) a removal device located outside the container and in fluid flow communication with the downstream open end of the conduit, wherein when an outer pressure in the removal device is less than an inner pressure taken inside the container, and upon changes in the orientation of the container, the liquid is caused to flow through the conduit from the enclosed volume to the removal device.

2. The assembly of claim 1 wherein the liquid is a cryogenic liquid and the conduit is of a flexible, synthetic polymeric material that is not adversely affected by contact with the cryogenic liquid.

3. The assembly of claim 2 wherein heat is added to the cryogenic liquid in the removal device to vaporize the liquid to a gas and wherein liquid removal from the container ceases at such time as the pressure inside the container essentially equals the pressure in the removal device.

4. The assembly of claim 1 wherein at least the portion of the conduit that reaches all of the enclosed volume intended to contain liquid is of polytetrafluoroethylene.

5. The assembly of claim 4 wherein the pick-up comprises a sinker submerged in the liquid.

6. The assembly of claim 4 wherein the pick-up comprises a float that rests on or slightly submerged below the surface of the liquid.

7. The assembly of claim 1 wherein the conduit comprises a plurality of flexible tubes.

8. An assembly for withdrawing a liquid from a closed container, the assembly comprising:

a) a conduit comprising an upstream open end disposed inside the container and an opposed downstream open end located outside the container;

b) a pick-up provided at the upstream open end of the conduit, wherein the pick-up comprises an enclosing side wall surrounding the upstream open end of the conduit disposed therein;

c) a wicking material housed inside the pick-up in a substantially surrounding relationship with the upstream open end of the conduit, wherein the enclosing side wall of the pick-up is provided with at least one perforation for enabling the wicking material to draw the liquid into the pick-up and wherein at least a portion of the conduit is of a flexible material that the conduit means provides for free and open flow to maintain contact of the pick-up with the liquid for withdrawing the liquid from the container at all times; and

d) a removal device located outside the container and in fluid flow communication with the downstream open end of the conduit, wherein when an outer pressure in the removal device is less than an inner pressure taken inside the container, the liquid in contact with the pick-up is caused to flow through the conduit from inside the container to the removal device.

9. The assembly of claim 8 wherein at least the portion of the conduit that provides for withdrawing the liquid at all times is of polytetrafluoroethylene.

10. The assembly of claim 8 wherein the pick-up comprises a sinker submerged in the liquid.

11. The assembly of claim 8 wherein the pick-up comprises a float that rests on or is submerged slightly below the surface of the liquid.

12. The assembly of claim 9 wherein the liquid is a cryogenic liquid and the conduit is of a flexible, synthetic polymeric material that is not adversely affected by contact with the cryogenic liquid.

13. The assembly of claim 12 wherein heat is added to the cryogenic liquid in the removal device to vaporize the liquid to a gas and wherein liquid removal from the container ceases at such time as the pressure inside the container essentially equals the pressure in the removal device.

14. An assembly for withdrawing cryogenic liquid contents from a closed container independent of the spatial orientation thereof, the assembly comprising:

a) a flexible conduit comprising an upstream open end disposed inside the container and an opposed downstream open end located outside the container;

b) a pick-up provided at the upstream open end of the conduit, wherein the pick-up comprises an enclosing side wall surrounding the upstream open end of the conduit disposed therein;

c) a wicking material housed inside the pick-up in a substantially surrounding relationship with the upstream open end of the conduit, and wherein the enclosing side wall of the pick-up is provided with at least one perforation for enabling the wicking material to draw the liquid into the pick-up and wherein at least a portion of the upstream open end of the conduit is of a synthetic polymeric material that is not adversely affected by the cryogenic liquid to thereby maintain contact with the liquid contents independent of the spatial orientation of the container;

d) a heat exchanger provided outside the container and in fluid flow communication with the downstream open end of the conduit, wherein independent of the spatial orientation of the container, the liquid contents are movable from inside the container to the heat exchanger via the conduit to transfer heat to the liquid and provide a raised-energy fluid and wherein liquid removal from the container ceases at such time as the pressure inside the container essentially equals the pressure in the heat exchanger; and

e) a consumption device provided to consume the raised-energy fluid from the heat exchanger so that a pressure differential is set up between the heat exchanger and the inside of the container through the conduit which causes the liquid contents to flow through the conduit and into the heat exchanger as the consumption device consumes the raised-energy fluid.

15. The assembly of claim 14 wherein the pick-up comprises a sinker submerged in the liquid.

16. The assembly of claim 14 wherein the pick-up comprises a float that rests upon or slightly below the surface of the liquid.

17. The assembly of claim 14 wherein at least the portion of the conduit that contacts the liquid contents independent of the spatial orientation of the container comprises a plurality of polytetrafluorethylene tubes.

18. The assembly of claim 14 wherein the cryogenic liquid is comprised of a breathable liquefied gas mixture containing oxygen and nitrogen.

19. The assembly of claim 14 wherein the container includes an inner container provided to store the cryogenic liquid and an insulator housing the inner container in a surrounding relationship to retard ambient heat conduction and radiation to the cryogenic liquid inside the inner container.

20. The assembly of claim 14 wherein the cryogenic liquid comprises a breathable gas mixture and wherein the consumption device comprises a facepiece that is worn by a user of the apparatus to breath the breathable gas mixture.

21. A method for withdrawing a liquid from a closed container, comprising the steps of:

a) providing a flexible conduit comprising an upstream open end disposed inside the container and an opposed downstream open end located outside the container, wherein at least a portion of the conduit is of a flexible material such that the conduit reaches all areas of the container intended to contain liquid upon changes in the orientation of the container while providing for free and open flow therethrough;

b) providing a pick-up at the upstream open end of the conduit, the pick-up comprising an enclosing side wall surrounding the upstream open end of the conduit disposed therein;

c) a wicking material housed inside the pick-up in a substantially surrounding relationship with the upstream open end of the conduit, and wherein the enclosing side wall of the pick-up has at least one perforation for enabling the wicking material to draw the liquid into the pick-up, thereby maintaining the upstream open end of the conduit in contact with the liquid;

d) providing a removal device located outside the container with the downstream open end of the conduit leading to the removal device;

e) creating a pressure differential between an outer pressure taken in the removal device and an inner pressure taken inside the container; and

f) withdrawing the liquid from the container to the removal device through the conduit when the outer pressure communicating through the conduit is less than the inner pressure inside the container.

22. The method of claim 21 including providing the liquid as a cryogenic liquid and the conduit of a flexible, synthetic polymeric material that is not adversely affected by contact with the cryogenic liquid.

23. The method of claim 22 wherein the removal device vaporizes the liquid to a breathable gas delivered to a user to support the user'"'"'s life.

24. The method of claim 21 wherein the pick-up further comprises a sinker submerged in the liquid regardless the spatial orientation of the container.

25. The method of claim 21 wherein the pick-up further comprises a float resting on or submerged slightly below the surface of the liquid.

26. The method of claim 21 wherein at least the portion of the conduit that contacts the liquid contents of the container is of a polytetrafluoroethylene.

27. A method for withdrawing cryogenic liquid contents from a closed container independent of the spatial orientation thereof, comprising the steps of:

a) providing a flexible conduit comprising an upstream open end disposed inside the container and an opposed downstream open end located outside the container, wherein at least a portion of the conduit is of a flexible material such that the conduit contacts the liquid contents independent of the spatial orientation of the container while maintaining free and open flow therethrough;

b) providing a pick-up at the upstream open end of the conduit, the pick-up comprising an enclosing side wall surrounding the upstream open end of the conduit disposed therein;

c) a wicking material housed inside the pick-up in a substantially surrounding relationship with the upstream open end of the conduit, and wherein the enclosing side wall of the pick-up has at least one perforation for enabling the wicking material to draw the liquid into the pick-up, thereby maintaining the upstream open end of the pick-up in contact with the liquid;

d) providing a heat exchanger outside the container and in fluid flow communication with the downstream open end of the conduit;

e) withdrawing the liquid contents from the container and moving the withdrawn liquid to the heat exchanger via the conduit to conduct heat energy to the liquid and provide a raised-energy fluid; and

f) consuming the raised-energy fluid from the heat exchanger, thereby setting up a pressure differential between the heat exchanger and the inside of the container causing the liquid contents to flow through the conduit and into the heat exchanger, and ceasing liquid consumption from the container at such time as the pressure inside the container essentially equals the pressure in the heat exchanger.

28. The method of claim 27 including providing the cryogenic liquid as a mixture of liquid oxygen and liquid nitrogen such that the raised-energy fluid is a breathable gas consumed by a user to support the user'"'"'s respiratory requirements.

29. The method of claim 27 wherein at least the portion of the conduit that contacts the liquid contents of the container is of a polytetrafluoroethylene.