Humidifier module for use in a gas humidification assembly

• US 4,921,642 A
• Filed: 12/27/1988
• Issued: 05/01/1990
• Est. Priority Date: 12/03/1987
• Status: Expired due to Term

• Current Assignee: Puritan Bennett Corp. (Medtronic Plc)
• Original Assignee: Puritan Bennett Corp. (Medtronic Plc)
• Inventors: LaTorraca, Gary J.
• Primary Examiner(s): Miles, Tim
• Application Number:
  US07/290,032
• Time in Patent Office: 490 Days
• Field of Search: 261/142, 261/104, 261/66, 219/271, 219/272, 128/203.27
• US Class Current: 261/142
• CPC Class Codes: A61M 16/1075 by influencing the temperature A61M16/1045 takes precedence
• CPC Class Codes: A61M 16/109 the humidifying liquid or the beneficial agent
• CPC Class Codes: A61M 16/142 with semi-permeable walls separating the liquid from the respiratory gas
• CPC Class Codes: A61M 16/16 Devices to humidify the respiration air A61M16/1045 takes precedence
• CPC Class Codes: A61M 16/162 Water-reservoir filling system, e.g. automatic
• CPC Class Codes: A61M 2205/3306 Optical measuring means
• CPC Class Codes: A61M 2205/3653 by Joule effect, i.e. electric resistance
• CPC Class Codes: F24F 2003/1435 comprising semi-permeable membrane
• CPC Class Codes: F24F 6/00 Air-humidification , e.g. cooling by humidification
• CPC Class Codes: F24F 6/02 by evaporation of water in the air

Abstract

The humidifier module for use in a gas humidification unit has a humidification chamber and a water heating chamber separated by a water vapor permeable, liquid water impermeable membrane. Gas inlet and outlet ports are provided in the humidification chamber, a water inlet port is provided for the water heating chamber, a water inlet port is provided for the water heating chamber, and a heat exchange wall is provided on one side of the water heating chamber to receive heat from a heat source in the humidification assembly. The gas humidification assembly has an enclosure adjacent the heat source, for receiving the humidifier module, a water supply source, and a controller of the heater and water supply to the humidifier module. A sensor is provided for monitoring the level of fluid within the humidification chamber, and another sensor is provided for monitoring the level of water within the water heating chamber.

Claims

1. A humidifier module for use in a gas humidification assembly having a heat source, a water supply source and an enclosure for receiving said module, wherein said module comprises:

(a) a housing forming a hollow shell adapted to be received in said enclosure;

(b) a water-vapor-permeable, liquid-water impermeable membrane disposed within said housing dividing said hollow shell into a first chamber and a second chamber and forming a common wall between said first and second chambers;

(c) said first chamber comprising a humidification chamber having a gas inlet port and gas outlet port; and

(d) said second chamber comprising a water heating chamber for receiving and containing heated liquid water, said water heating chamber having a water inlet port and a heat exchange member for indirectly heating said liquid water, said heat exchange member being formed of material capable of high heat transfer, said heat exchange member being adapted to receive heat from said heat source of said gas humidifier assembly, and said membrane forming a liquid water retaining wall of said water heating chamber for permitting water vapor generated from said heated liquid water to pass from said water heating chamber to said humidification chamber, while preventing liquid water from passing from said water heating chamber to said humidification chamber.

2. The humidifier module of claim 1, wherein said housing includes means for positioning said module in heat receiving relationship with said heat source of said gas humidifier assembly.

3. The humidifier module of claim 2, wherein said means for positioning includes first means for making a snap fit connection with a mating second means for making a snap fit connection in said gas humidifier assembly.

4. The humidifier module of claim 1, wherein said housing includes a means for receiving light adapted to be in light receiving relationship with a light source in said gas humidification assembly, said means for receiving light reflecting a first amount of light when said water heating chamber contains less than a predetermined level of water and a different amount of light when water in said water heating chamber reaches said level.

5. The humidifier module of claim 1, wherein said housing includes a means for receiving light adapted to be in light receiving relationship with a light source in said gas humidification assembly, said means for receiving light reflecting a first amount of light when said humidification chamber contains less than a predetermined level of fluid and different amount of light when fluid in said humidification chamber reaches said level.

6. The humidifier module of claim 1, wherein said heat exchange member comprises a metal plate which forms a wall of the water heating chamber.

7. The humidifier module of claim 6, wherein said metal plate is aluminum.

8. The humidifier of claim 1, wherein said heat exchange member comprises a metal plate having at least a portion with a frustoconical shape projecting away from said heat source.

9. The humidifier of claim 8 wherein said heat source is disposed approximately equidistant the frustoconical portion of said metal plate.

10. The humidifier of claim 1, wherein said heat exchange member comprises a wall having at least a portion projecting away from said heat source.

11. The humidifier of claim 10, wherein said heat source is disposed approximately symmetrically distant from said wall portion projecting away from said heat source.

12. The humidifier module of claim 1, wherein said membrane comprises a polytetrarluoroethylene filter.

13. The humidifier module of claim 1, wherein at least a portion of said housing forming said humidification chamber is transparent, whereby an operator may observe fluid levels within said module.

14. The humidifier module of claim 1, wherein said housing comprises a base portion including said heat exchange member and said water inlet, and a vapor chamber portion including said gas inlet and outlet, said membrane adapted to be received in liquid water sealing relationship between said base portion and said vapor chamber portion, and said housing further comprising a means for sealably securing said base portion to said vapor chamber portion.

15. The humidifier module of claim 1, wherein said membrane is removable from said housing.

16. In combination with a gas humidification assembly having a heater, an enclosure, means for supplying water for humidifying gas, means for controlling the heater, and means for controlling a water supply, the improvement which comprises a humidifier module adapted to be seated within the enclosure having a gas inlet port and a gas outlet port for circulation of the gas through said module, said module comprising:

(a) a housing forming a hollow shell;

(b) a water-vapor-permeable, liquid-water impermeable membrane disposed within said housing and dividing said hollow shell into a vapor chamber and a water heating chamber for receiving and containing heated liquid water, said water heating chamber sharing said membrane as a common wall;

(c) said vapor chamber including said gas inlet port and said gas outlet port; and

(d) said water heating chamber having a water inlet port in communication with said water supply and a heat exchange member for indirectly heating said liquid water, said heat exchange member being formed of material capable of high heat transfer, said heat exchange member being adapted to receive heat from said heater, and said membrane forming a liquid water retaining wall of said water heating chamber for permitting water vapor generated from said heated liquid water to pass from said water heating chamber to said humidification chamber, while preventing liquid water from passing from said water heating chamber to said humidification chamber.

17. The combination of claim 16 further including means for positioning said module within the enclosure in heat receiving relationship with said heater.

18. The combination of claim 17 wherein said means for positioning includes at least one first means on said module for making a snap fit connection with at least one corresponding second means for making a snap fit connection located on said gas humidification assembly.

19. The combination of claim 16, further including a light source, a means in said module for receiving light from said light source, and a means for sensing light transmitted from said means for receiving light as a function of the presence of a predetermined level of water in the water heating chamber of said module.

20. The combination of claim 16, further including a light source, a means in said module for receiving light from said light source and a means for sensing light transmitted from said means for receiving light as a function of the presence of a predetermined level of fluid in the vapor chamber of said module.

21. The combination of claim 16, wherein said heat exchange member comprises a metal plate which forms a wall of the water heating chamber.

22. The humidifier of claim 16, wherein said heat exchange member comprises a metal plate having at least a portion with a frustoconical shape projecting away from said heater.

23. The humidifier of claim 22, wherein said heater is disposed approximately equidistant the frustoconical portion of said metal plate.

24. The humidifier of claim 16, wherein said heat exchange member comprises a wall having at least a portion projecting away from said heater.

25. The humidifier of claim 24, wherein said heater is disposed approximately symmetrically distant from said wall portion projecting away from said heater.

26. The combination of claim 16, wherein said metal plate comprises aluminum.

27. The combination of claim 16, wherein at least a portion of said housing forming said vapor chamber is transparent.

28. The combination of claim 16, wherein said module housing comprises a base portion and a vapor chamber portion, said base portion including said heat exchange member, said water inlet and said water heating chamber, and said vapor chamber portion including said vapor chamber, said membrane being adapted to be received in liquid water sealing relationship between said base portion and said vapor chamber portion, and further including a locking ring adapted to engage means for interlocking on said base portion for releasably securing said base portion and said vapor chamber portion together, with said membrane position therebetween.

29. The combination of claim 16, wherein said means for controlling said water supply is operatively connected to said water supply and is operatively connected to a sensor adapted to provide a signal to said means for controlling said water supply indicating whether there is a predetermined level of water in said water heating chamber, whereby when water in said water heating chamber is below a predetermined level said means for controlling said water supply operates to provide water from said water supply to said water heating chamber, and when water in said water heating chamber reaches said predetermined level said means for controlling said water supply operates to stop provision of water to said water heating chamber.

30. The combination of claim 16, further including a light source, a means in said module for receiving light from said light source, and a means for sensing refraction of light away from said means for receiving light as a function of the presence of a predetermined level of water in the water heating chamber of said module.

31. The combination of claim 16, further including a light source, a means in said module for receiving light from said light source, and a means for sensing refraction of light away from said means for receiving light as a function of the presence of a predetermined level of fluid in the vapor chamber.

32. The combination of claim 16, further including means for generating an alarm signal when fluid in said vapor chamber reaches said predetermined level.

33. The combination of claim 31, further including means for generating an alarm signal when fluid in said vapor chamber reaches said predetermined level.

34. The combination of claim 16, wherein said means for controlling said water supply includes an optical sensor in said humidifier assembly and a means for receiving light in said module, said means for receiving light being adapted to transmit a first amount of light to said optical sensor when said water heater chamber contains a predetermined level of water and a second amount of light when said water chamber does not contain said level of water, said optical sensor being adapted to provide a first signal to said means for controlling said water supply in response to said first amount of transmitted light and a second signal in response to said second amount of transmitted light, said means for controlling said water supply being adapted to cause water to be supplied to said water heater chamber when said second signal is received by said means for controlling said water supply.

35. The combination of claim 16, wherein said means for controlling said heater includes an optical sensor in said humidifier assembly and a means for receiving light in said module, said means for receiving light adapted to transmit a first amount of light to said optical sensor when said vapor chamber contains less than a predetermined level of fluid and a second amount of light when said vapor chamber contains said predetermined level of fluid, said optical sensor being adapted to provide a first signal to said means for controlling said heater in response to said first amount of transmitted light and a second signal in response to said second amount of transmitted light, said means for controlling said heater being adapted to cause an alarm to be activated when said second signal is received by said means for controlling said heater.