Humidifier for a thermal support apparatus

• US 6,024,694 A
• Filed: 09/09/1997
• Issued: 02/15/2000
• Est. Priority Date: 09/25/1995
• Status: Expired due to Term

• Current Assignee: Draeger Medical Incorporated (FPS Vermögensverwaltung GmbH)
• Original Assignee: Hill-Rom Incorporated (Baxter International Inc.)
• Inventors: Smith, Douglas K., Goldberg, Charles, Speraw, Floyd G.
• Primary Examiner(s): Lacyk, John P.
• Application Number:
  US08/926,383
• Time in Patent Office: 889 Days
• Field of Search: 600/21-22
• US Class Current: 600/22
• CPC Class Codes: A61F 2007/006 of gas
• CPC Class Codes: A61F 2007/0088 Radiating heat
• CPC Class Codes: A61G 11/00 Baby-incubators; Couveuses
• CPC Class Codes: A61G 11/002 height-adjustable patient support
• CPC Class Codes: A61G 11/005 with movable walls, e.g. for accessing the inside, removable walls
• CPC Class Codes: A61G 11/009 with hand insertion windows, e.g. in the walls
• CPC Class Codes: A61G 2203/46 for temperature
• CPC Class Codes: A61G 2203/723 Impact absorbing means, e.g. bumpers or airbags
• CPC Class Codes: A61G 2210/50 for radiography
• CPC Class Codes: A61G 7/012 raising or lowering of the whole mattress frame A61G7/005, A61G7/008 take precedence
• CPC Class Codes: A61M 16/024 including calculation means, e.g. using a processor
• CPC Class Codes: A61M 16/107 in the inspiratory path
• CPC Class Codes: A61M 16/109 the humidifying liquid or the beneficial agent
• CPC Class Codes: A61M 16/16 Devices to humidify the respiration air A61M16/1045 takes precedence
• CPC Class Codes: A61M 2205/3389 Continuous level detection A61M2205/3393 takes precedence
• CPC Class Codes: F24F 11/30 for purposes related to the operation of the system, e.g. for safety or monitoring
• CPC Class Codes: F24F 2110/10 Temperature
• CPC Class Codes: F24F 9/00 Use of air currents for screening, e.g. air curtains
• CPC Class Codes: G05D 23/1917 using digital means

Abstract

A humidifier module is provided for a patient support apparatus which includes an opening into which the module is inserted, an electrical service connector, an air inlet port, and an air outlet port. The humidifier module includes a water reservoir and a heater configured to heat water in the reservoir. An air chamber with an air inlet port and an air exhaust port for mating with air inlet and outlet ports of the patient support apparatus and an electrical connector for mating with the electrical service connector of the patient support apparatus is included in the humidifier module. When the humidifier module is inserted into the patient support apparatus, the patient support apparatus is provided with a humidified environment for a patient.

Claims

1. A humidifier module for a patient-support apparatus including an opening into which the module is inserted, an electrical service connector, an air inlet port, and an air outlet port, the humidifier module comprising

a water reservoir configured to hold water,

a heater configured to heat the water,

an air chamber with an air inlet port and an air exhaust port for mating with the air inlet and outlet ports of the patient-support apparatus, and an electrical connector for mating with the electrical service connector of the patient-support apparatus,

whereby the patient-support apparatus is provided with a humidified environment for a patient when the humidifier module is inserted into the patient-support apparatus.

2. The humidifier module of claim 1, wherein the patient-support apparatus includes one or more external doors that normally close the opening of the patient-support apparatus and wherein the doors are opened by the insertion of the humidifier module into the patient-support apparatus.

3. The humidifier module of claim 2, wherein the patient-support apparatus includes one or more internal doors that normally close the air inlet and outlet ports of the patient-support apparatus and wherein the doors are opened by the insertion of the humidifier module into patient-support apparatus.

4. The humidifier module of claim 3, wherein the module includes at least one spill damper doors and wherein the at least one spill damper door acts as a stop for preventing hot water heated by the heater from spilling out of the module.

5. The humidifier module of claim 3, wherein the heater is located in a chamber below the water reservoir.

6. The humidifier module of claim 5, wherein the module includes a control valve that connects the reservoir and the heater and the control valve is actuatable between an opened configuration in which water flows from the reservoir to the heater and a closed configuration in which water is prevented from flowing from the reservoir to the heater.

7. The humidifier module of claim 2, wherein the module includes one or more spill damper doors and wherein the door or doors act as a stop for preventing hot water heated by the heater from spilling out of the module.

8. The humidifier module of claim 7, wherein the heater is located in a chamber below the water reservoir.

9. The humidifier module of claim 8, wherein the module includes a control valve that connects the reservoir and the heater and the control valve is actuatable between an opened configuration in which water flows from the reservoir to the heater and a closed configuration in which water is prevented from flowing from the reservoir to the heater.

10. The humidifier module of claim 2, wherein the heater is located in a chamber below the water reservoir.

11. The humidifier module of claim 10, wherein the module includes a control valve that connects the reservoir and the heater and the control valve is actuatable between an opened configuration in which water flows from the reservoir to the heater and a closed configuration in which water is prevented from flowing from the reservoir to the heater.

12. The humidifier module of claim 1, wherein the patient-support apparatus includes one or more internal doors that normally close the air inlet and outlet ports of the patient-support apparatus and wherein the doors are opened by the insertion of the humidifier module into patient-support apparatus.

13. The humidifier module of claim 12, wherein the module includes one or more spill damper doors and wherein the door or doors act as a stop for preventing hot water heated by the heater from spilling out of the module.

14. The humidifier module of claim 13, wherein the heater is located in a chamber below the water reservoir.

15. The humidifier module of claim 14, wherein the module includes a control valve that connects the reservoir and the heater and the control valve is actuatable between an opened configuration in which water flows from the reservoir to the heater and a closed configuration in which water is prevented from flowing from the reservoir to the heater.

16. The humidifier module of claim 12, wherein the heater is located in a chamber below the water reservoir.

17. The humidifier module of claim 16, wherein the module includes a control valve that connects the reservoir and the heater and the control valve is actuatable between an opened configuration in which water flows from the reservoir to the heater and a closed configuration in which water is prevented from flowing from the reservoir to the heater.

18. The humidifier module of claim 1, wherein the module includes one or more spill damper doors and wherein the door or doors act as a stop for preventing hot water heated by the heater from spilling out of the module.

19. The humidifier module of claim 18, wherein the heater is located in a chamber below the water reservoir.

20. The humidifier module of claim 19, wherein the module includes a control valve that connects the reservoir and the heater and the control valve is actuatable between an opened configuration in which water flows from the reservoir to the heater and a closed configuration in which water is prevented from flowing from the reservoir to the heater.

21. The humidifier module of claim 1, wherein the heater is located in a chamber below the water reservoir.

22. The humidifier module of claim 21, wherein the module includes a control valve that connects the reservoir and the heater and the control valve is actuatable between an opened configuration in which water flows from the reservoir to the heater and a closed configuration in which water is prevented from flowing from the reservoir to the heater.

23. The humidifier module of claim 1, wherein the module includes a control valve that connects the reservoir and the heater and the control valve is actuatable between an opened configuration in which water flows from the reservoir to the heater and a closed configuration in which water is prevented from flowing from the reservoir to the heater.

24. The humidifier module of claim 1, wherein a substantial portion of each of the water reservoir, the heater, and the air chamber pass through the opening of the patient-support apparatus as the humidifier module is inserted into the patient-support apparatus.

25. A patient-support apparatus comprising

a base,

a patient support supported above the base, the patient support being formed to include an opening, an air inlet port, and an air outlet port,

an electrical service connector coupled to the patient support adjacent to the opening, and

a humidifier module including

a container for holding water and providing an air chamber above the water, the container including an air inlet port that mates with the air outlet port of the patient-support apparatus when the humidifier module is inserted into the opening so that air can move through the air outlet port of the patient-support apparatus and into the air chamber, the container including an air exhaust port that mates with the air inlet port of the patient-support apparatus when the humidifier module is inserted into the opening so that air can move out of the air chamber and through the air inlet port of the patient-support apparatus, and

a heater for heating the water, the heater including an electrical connector that aligns with and automatically connects to the electrical service connector of the patient-support apparatus to receive power therefrom when the humidifier module is inserted into the opening,

whereby the patient-support apparatus is provided with a humidified environment for a patient when the humidifier module is inserted into the patient-support apparatus.

26. The patient-support apparatus of claim 25, wherein the patient support further includes at least one door that normally closes the opening, insertion of the humidifier module through the opening opens the at least one door, and the at least one door closes automatically when the humidifier module is removed from the opening of the patient-support apparatus.

27. The patient-support apparatus of claim 26, wherein the at least one door includes a door that is opened by the electrical connector of the humidifier module when the humidifier module is inserted into the opening so that the electrical service connector of the patient-support apparatus is accessible to the electrical connector of the humidifier module.

28. The patient-support apparatus of claim 26, wherein the at least one door includes a first door that pivots about a first axis in a first direction when the humidifier module is inserted through the opening and a second door that pivots about a second axis in a second direction opposite to the first direction when the humidifier module is inserted through the opening.

29. The patient-support apparatus of claim 28, wherein the first axis and the second axis are both substantially vertical.

30. The patient-support apparatus of claim 25, wherein the humidifier module further includes a water reservoir adjacent to the container and configured to hold water separately from the container.

31. The patient-support apparatus of claim 30, wherein the humidifier module includes a control valve that couples the water reservoir to the container and the control valve is actuatable between an opened configuration in which water flows from the water reservoir to the container and a closed configuration in which water is prevented from flowing from the reservoir to the container.

32. The patient-support apparatus of claim 31, wherein the humidifier module includes a water level sensor that senses the level of the water in the container and provides a signal to the control valve to actuate the control valve between the opened and closed configurations.

33. The patient-support apparatus of claim 30, wherein a substantial portion of the water reservoir is positioned to lie inside the patient support while the humidifier module is inserted through the opening, the humidifier module further includes a refill door that is positioned to lie outside the patient support while the humidifier module is inserted through the opening, and the refill door can be opened to allow water to be poured into the water reservoir.

34. The patient-support apparatus of claim 25, wherein the patient-support apparatus is formed to include an aperture adjacent to the opening, the humidifier module further includes a locking pin, and the locking pin is movable between a locking position extended into the aperture to prevent the humidifier module from being removed from the opening and a releasing position retracted out of the opening to allow the humidifier module to be removed from the opening.

35. The patient-support apparatus of claim 34, wherein the humidifier module includes a solenoid coupled to the locking pin and the solenoid is actuatable to move the locking pin between the locking and releasing positions.

36. The patient-support apparatus of claim 35, wherein the humidifier module further includes a temperature sensor that senses the temperature of a surface of the humidifier module and provides a signal to the solenoid to actuate the solenoid to move the locking pin between the locking and releasing positions.

37. A humidifier module for a patient-support apparatus including an opening into which the module is inserted, an electrical service connector, an air inlet port, and an air outlet port, the humidifier module comprising

a container for holding water and providing an air chamber above the water, the container including an air inlet port that mates with the air outlet port of the patient-support apparatus when the humidifier module is inserted into the opening so that air can move through the air outlet port of the patient-support apparatus and into the air chamber, the container including an air exhaust port that mates with the air inlet port of the patient-support apparatus when the humidifier module is inserted into the opening so that air can move out of the air chamber and through the air inlet port of the patient-support apparatus, and

a heater for heating the water, the heater including an electrical connector that couples to the electrical service connector of the patient-support apparatus to receive power therefrom when the humidifier module is inserted into the opening, the heater being positioned to lie beneath the water to be heated,

whereby the patient-support apparatus is provided with a humidified environment for a patient when the humidifier module is inserted into the patient support system.

38. The humidifier module of claim 37, wherein the heater includes a heater pan that holds water and a heater pad that heats the water and the heater pad is coupled to a bottom surface of the heater pan.

39. The humidifier module of claim 38, wherein the container includes a bottom wall and the heater pad is positioned to lie between the bottom surface of the heater pan and the bottom wall of the container.

40. The humidifier module of claim 37, further comprising a locking pin that locks the humidifier module to the patient-support apparatus when the heater temperature exceeds a threshold temperature and an indicator that indicates that the humidifier is locked to the patient-support apparatus.

41. A patient-support apparatus comprising

a patient support including a fluid circulation system having a flow path along which circulated fluid is directed to provide a thermally controlled environment for a patient, a compartment for accepting a removable humidifier module, an inlet port in fluid communication with the compartment, and an outlet port in fluid communication with the compartment,

a first door pivotably coupled to the patient support and normally closing the inlet port,

a second door pivotably coupled to the patient support and normally closing the outlet port, and

a humidifier module including a water container for containing water, an inlet port for connecting with the outlet port of the patient support when the humidifier module is inserted into the compartment, an exhaust port for connecting with the inlet port of the patient support when the humidifier module is inserted into the compartment, and first and second door openers arranged to engage and pivot the respective first and second doors to an opened position to allow at least some of the fluid in the flow path to be diverted through the humidifier module and over the water contained in the water container.

42. The patient-support apparatus of claim 41, wherein the patient support further includes a pivot pin and the first and second doors are both mounted on the pivot pin for pivoting movement.

43. The patient-support apparatus of claim 42, wherein the pivot pin extends vertically.

44. The patient-support apparatus of claim 43, wherein the first door opener is spaced apart from the second door opener to define a pin-receiving space therebetween and the pivot pin is positioned to lie in the pin-receiving space when the humidifier module is inserted into the compartment.

45. The patient-support apparatus of claim 43, wherein the first and second doors pivot in opposite directions toward one another as the first and second doors pivot in response to insertion of the humidifier module into the compartment.

46. The patient-support apparatus of claim 42, wherein the first and second doors pivot in opposite directions toward one another in response to insertion of the humidifier module into the compartment.

47. The patient-support apparatus of claim 42, wherein the patient support includes a wall portion spaced apart from the pivot pin to define an orifice therebetween, the circulated fluid flows through the orifice when the humidifier module is removed from the compartment, and at least one of the first and second doors extend between the wall portion and the pivot pin to close the orifice when the humidifier module is inserted into the compartment.

48. The patient-support apparatus of claim 41, wherein the humidifier module further includes a first spill damper door that closes the inlet port of the humidifier module when removed from the compartment and a second spill damper door that closes the exhaust port of the humidifier module when removed from the compartment.

49. The patient-support apparatus of claim 48, wherein the patient support further includes third and fourth door openers arranged to engage and move the respective first and second spill damper doors to open the inlet port and the exhaust port of the humidifier module when the humidifier module is inserted into the compartment.

50. The patient-support apparatus of claim 48, wherein the third and fourth door openers pivot the first and second spill damper doors upwardly relative to the water container as the humidifier module is inserted into the compartment.

51. The patient-support apparatus of claim 41, wherein the first door opener is positioned to lie beneath the inlet port of the humidifier module, the second door opener is positioned to lie beneath the exhaust port of the humidifier module, and each of the first and second door openers is formed to include a recess for catching water that spills out of the water container through the inlet and exhaust ports.

52. A patient-support apparatus comprising

a patient support having a first chamber, a second chamber, and a fluid-flow orifice between the first and second chambers,

a fan positioned to lie in the first chamber and operable to move fluid through the orifice into the second chamber, and

laminar flow profile structure appended to the patient support in the second chamber and configured to maintain laminar flow of the fluid as the fluid enters the second chamber from the first chamber.

53. The patient-support apparatus of claim 52, wherein the patient support includes a pair of transverse walls and a pair of longitudinal walls that subdivide the second chamber into a mattress well and a channel that substantially encompasses the mattress well and the laminar profile structure is configured to direct substantially equivalent amounts of fluid along each of the longitudinal walls.

54. The patient-support apparatus of claim 53, wherein the laminar flow profile structure includes a center divider having an apex at the fluid-flow orifice and a pair of curved surfaces that extend from the apex and toward one of the transverse walls.

55. The patient-support apparatus of claim 54, further comprising a cover plate positioned to lie in the second chamber and the center divider is appended to and extends downwardly from the cover plate.

56. The patient-support apparatus of claim 53, wherein the patient support includes a platform tub in which the mattress well and channel are formed and a platform cover positioned to lie above the channel, the platform cover is formed to include a mattress-receiving aperture that mates with the mattress well and a plurality of vent slots that are arranged around the mattress-receiving aperture, and the vent slots are in fluid communication with the channel so that some of the fluid flowing in the channel passes upwardly through each of the vent slots.

57. The patient-support apparatus of claim 56, wherein the patient support includes a bottom wall having a datum surface in the first chamber and inclined surfaces in the second chamber, the inclined surfaces are positioned to lie in the channel, and the inclined surfaces are configured so that air exits each vent slot of the platform cover at a velocity that is close to a target velocity.

58. The patient-support apparatus of claim 56, further comprising a cover plate positioned to lie in the second chamber above the bottom wall and adjacent to one of the transverse walls and at least one of the vent slots being positioned to lie above the cover plate.

59. The patient-support apparatus of claim 58, wherein the cover plate is formed to include at least one bleeder hole that allows a portion of the fluid to pass upwardly therethrough toward the at least one vent slot that is positioned to lie above the cover plate.

60. The patient-support apparatus of claim 52, wherein the laminar flow profile structure includes a center divider configured to divert the fluid to flow along two separate paths within the patient support and the center divider is configured so that substantially equivalent amounts of fluid are diverted along each path.

61. The patient-support apparatus of claim 60, wherein the laminar flow profile structure further includes an apex at the orifice.

62. The patient-support apparatus of claim 61, wherein the center divider includes a pair of concave curved surfaces that extend from the apex through an angle of approximately 90°

.

63. The patient-support apparatus of claim 60, further comprising a cover plate extending beyond opposite sides of the center divider.

64. A humidifier module for a patient-support apparatus including a fluid circulation system for circulating fluid and an opening into which the humidifier module is inserted, the humidifier module comprising

a container for holding water and providing an air chamber above the water, the container including an air inlet and an air outlet, the fluid circulation system moving air through the air chamber,

a heater for heating the water,

a water reservoir for holding additional water,

a control valve coupled to the water reservoir and coupled to the container, the control valve having a closed configuration blocking the flow of water from the water reservoir to the container and the control valve having an opened configuration allowing the flow of water from the water reservoir to the container, and

a level sensor for sensing the water level in the container and providing a signal to the control valve to move the control valve between the opened and closed configurations.

65. The humidifier module of claim 64, wherein the level sensor is a refractive light sensor.

66. The humidifier module of claim 64, wherein the water reservoir is positioned to lie above the container and the additional water flows from the water reservoir to the container when the control valve is in the opened configuration due to gravity.

67. A patient-support apparatus comprising

a patient support including a fluid circulation system for circulating fluid, a compartment for accepting a removable self-contained humidifier module, and a lock pin-receiving space adjacent to the compartment,

a humidifier module comprising

a container for holding water and providing an air chamber above the water, the fluid circulation system circulating fluid through the air chamber when the humidifier module is inserted into the opening,

a heater for heating the water,

a temperature sensor for sensing the temperature of a surface of the humidifier module, and

a locking mechanism including a locking pin, the locking mechanism being coupled to the temperature sensor and configured to move the locking pin in response to the temperature sensed by the temperature sensor, the locking pin having an extended position received in the lock-pin receiving space to lock the humidifier module to the patient support when the temperature sensed exceeds a predetermined temperature, and the locking pin having a retracted position pulled out of the lock pin-receiving space to unlock the humidifier module from the patient support when the temperature sensed is below the predetermined temperature.

68. The patient-support apparatus of claim 67, wherein the locking mechanism includes a solenoid that is electrically actuated to move the locking pin between the extended and retracted positions.

69. The patient-support apparatus of claim 67, wherein the heater includes a heater pan and a heater pad and the temperature sensor is positioned to lie between the heater pan and the heater pad.

70. The patient-support apparatus of claim 67, wherein the patient support includes a platform tub in which the compartment is formed and a member adjacent to a portion of the compartment and the lock-pin receiving space is formed in the member.

71. The patient-support apparatus of claim 70, wherein the member extends over a portion of the compartment, the lock-pin receiving space is an aperture formed in the member, and the locking pin moves vertically into and out of the aperture.