HUMIDIFIER AND/OR FLOW GENERATOR FOR CPAP

• US 20110283999A2
• Filed: 08/15/2006
• Published: 11/24/2011
• Est. Priority Date: 08/15/2005
• Status: Active Grant

• Current Assignee: ResMed Pty Ltd. (ResMed Incorporated)
• Original Assignee: Resmed Limited (ResMed Incorporated)
• Inventors: Smith, Ian, Snow, John, Lithgow, Perry, Kao, Dan
• Granted Patent: US 9,038,629 B2
• Time in Patent Office: Days
• US Class Current: 128/203.160
• CPC Class Codes: A61M 16/0057 Pumps therefor
• CPC Class Codes: A61M 16/0066 Blowers or centrifugal pumps
• CPC Class Codes: A61M 16/0075 Bellows-type
• CPC Class Codes: A61M 16/0616 with face sealing means comprising a flap or membrane projecting inwards, such that sealing increases with increasing inhalation gas pressure
• CPC Class Codes: A61M 16/0666 Nasal cannulas or tubing devices for improving normal breathing through the nose A61F5/08; nose filters A62B23/06; outside holding devices A61M25/02
• CPC Class Codes: A61M 16/08 Bellows; Connecting tubes having means for taking samples G01N1/22; Water traps; Patient circuits
• CPC Class Codes: A61M 16/0816 Joints or connectors
• CPC Class Codes: A61M 16/0875 Connecting tubes
• CPC Class Codes: A61M 16/10 Preparation of respiratory gases or vapours
• 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 16/16 Devices to humidify the respiration air A61M16/1045 takes precedence
• CPC Class Codes: A61M 2205/02 characterised by a particular materials
• CPC Class Codes: A61M 2205/21 insensitive to tilting or inclination, e.g. spill-over prevention
• CPC Class Codes: A61M 2205/3334 Measuring or controlling the flow rate
• CPC Class Codes: A61M 2205/42 Reducing noise
• CPC Class Codes: A61M 2209/086 Docking stations
• CPC Class Codes: B01D 47/02 by passing the gas or air or vapour over or through a liquid bath

Abstract

A CPAP device includes a humidifier including humidifier tub having a heat conducting base plate; and a cradle to support the humidifier tub in an operative position. The cradle may also support a flow generator in operative relation to the humidifier tub. The cradle includes a heater plate in communication with the heat conducting base plate of the humidifier tub in use. The cradle further includes a retaining mechanism to retain the humidifier tub in the cradle, the retaining mechanism being structured to force the base plate into engagement with the heater plate. The humidifier and/or flow generator may include various features to manage inadvertent back-spill of water from the humidifier to the flow generator.

Claims

1. A CPAP device comprising:

a humidifier tub including a heat conducting base plate; and

a cradle to support the humidifier tub in an operative position, the cradle including a fixed heater plate in communication with the heat conducting base plate of the humidifier tub in use, the cradle further including a retaining mechanism to retain the humidifier tub in the cradle, the retaining mechanism structured to force the base plate into engagement with the heater plate wherein the retaining mechanism includes a biasing structure that forces the base plate in a direction towards the heater plate, the biasing structure configured to allow disengagement during installation of the humidifier tub with the cradle and reengagement after installation of the humidifier tub.

2. The CPAP device according to claim 1, wherein the biasing structure includes at least one spring that forces the base plate into engagement with the heater plate.

3. The CPAP device according to claim 1, wherein the retaining mechanism includes a securing catch that lifts up and down to enable release or insertion of the humidifier tub.

4. The CPAP device according to claim 1, wherein the retaining mechanism includes a docking portion that is slidable between a humidifier locking position and a humidifier unlocking position.

5. The CPAP device according to claim 1, wherein the retaining mechanism includes a spring-biased clamping edge that clamps the humidifier tub to the cradle.

6. The CPAP device according to claim 1, wherein the retaining mechanism includes a pivotable front guard and a pivotable humidifier retaining portion, the front guard being pivotable in a first direction to release the humidifier retaining portion for receiving the humidifier tub and pivotable in an opposing second direction to secure the humidifier retaining portion together with the humidifier tub in the operative position.

7. The CPAP device according to claim 1, wherein the retaining mechanism includes a front guard that enables release or insertion of the humidifier and at least two pressure pads that maintain engagement between the base plate and the heater plate.

8. The CPAP device according to claim 1, further comprising a flow generator provided to the cradle and in communication with the humidifier tub.

9. The CPAP device according to claim 8, wherein the flow generator includes a motor having a motor outlet, a muffler chamber having an inlet coupled to the motor outlet and an muffler outlet in communication with a flow generator outlet.

10. The CPAP device according to claim 9, wherein an axis of the motor outlet is offset from an axis of the muffler outlet and/or the flow generator outlet.

11. The CPAP device according to claim 9, wherein the muffler chamber is structured to store a predetermined amount of water that may be inadvertently introduced into the flow generator outlet from the humidifier.

12. The CPAP device according to claim 9, wherein said muffler chamber includes an upper part conduit portion and a lower storage portion integrally formed with the part conduit portion.

13. The CPAP device according to claim 9, wherein the predetermined amount of water is about 100 ml.

15. The CPAP device according to claim 1, wherein the cradle and/or humidifier tub includes alignment structure such that the tub can only be oriented in one way relative to the cradle.

16. The CPAP device according to claim 1, further comprising a locking structure to secure the humidifier tub relative to the cradle during use.

18. The CPAP device according to claim 1, wherein the heater plate includes a ceramic heating element.

14. (canceled)

17. (canceled)

19. A method for retaining a humidifier tub to a cradle, comprising:

providing a cradle including a retaining mechanism, the retaining mechanism including a biasing structure;

moving the retaining mechanism to a first position that enables insertion of the humidifier and disables the biasing structure;

providing the humidifier tub to the cradle; and

moving the retaining mechanism to a second position that secures the humidifier tub in an operative position

and enables the biasing structure to force a heat conducting base plate of the humidifier tub into engagement with a fixed heater plate of the cradle.

70. A method according to claim 19, wherein the biasing structure includes at least one spring.

20. A CPAP device comprising a flow generator including a flow generator outlet, a motor having a motor outlet, a muffler chamber having an inlet coupled to the motor outlet and a muffler chamber outlet in communication with a flow generator outlet, wherein an axis of the motor outlet is offset from an axis of the muffler chamber outlet and/or the flow generator outlet.

21. The CPAP device according to claim 20, wherein the muffler chamber is structured to store a predetermined amount of water that may be inadvertently introduced into the flow generator outlet from the humidifier.

22. The CPAP device according to claim 21, wherein the predetermined amount of water is about 100 ml.

23. A CPAP device comprising a flow generator including a flow generator outlet, a motor having a motor outlet, a muffler chamber having an inlet coupled to the motor outlet and a muffler chamber outlet in communication with a flow generator outlet, wherein said muffler chamber includes an upper part conduit portion and a lower storage portion integrally formed with the part conduit portion.

24. The CPAP device according to claim 23, wherein the upper part conduit portion includes inlet and outlet fittings to be coupled with the motor outlet and the flow generator outlet, respectively.

25. The CPAP device according to claim 23, wherein an axis of the motor outlet is aligned with an axis of the muffler chamber outlet and/or the flow generator outlet.

26. The CPAP device according to claim 23, wherein the lower storage portion is structured to store a predetermined amount of water that may be inadvertently introduced into the flow generator outlet from the humidifier.

27. The CPAP device according to claim 26, wherein the predetermined amount of water is about 100 ml.

28. A humidifier assembly adapted to be coupled to a flow generator, the humidifier assembly comprising:

a cradle having a tub support surface and a heater plate provided to the tub support surface;

a humidifier supported by the cradle and including a tub having an inlet positioned on a rear wall of the tub and an outlet located on a top lid of the tub, the inlet being adapted to be in fluid communication with an output from the flow generator in use, the outlet of the tub being adapted to be in fluid communication with an air delivery conduit in use;

the humidifier including a heat conducting base plate provided to a bottom portion of the tub and adapted to be in thermal contact with the heater plate of the cradle when the tub is positioned within the cradle by sliding the tub from front to back relative to the cradle, the tub and base plate defining a chamber that is adapted to receive a volume of water, wherein, in use, a supply of pressurized air from the flow generator enters the inlet of the tub and collects moisture through contact with water within the tub before continuing on to the outlet of the tub;

a connector positioned adjacent the inlet of the tub, the connector including an attaching portion and a flexible sealing portion formed in one piece with the attaching portion, the flexible sealing portion defining a face seal of silicone, the face seal comprising an aperture that is adjacent to or abuts a flat surface surrounding the inlet of the tub when the tub is properly docked on the cradle, wherein the flexible sealing portion has a diameter that is greater than a diameter of the attaching portion.

29. A humidifier assembly according to claim 28, wherein the face seal comprises a conforming, bellows-type seal.

30. A humidifier assembly according to claim 29, wherein the bellows-type seal includes an internal channel positioned adjacent the inlet of the tub in use.

31. A humidifier assembly according to claim 30, wherein the attaching portion includes a sealing element.

32. A humidifier assembly according to claim 31, wherein the flexible sealing portion is constructed such that it does not have any split lines.

33. A humidifier assembly according to claim 31, wherein the aperture on the face seal is larger than an inlet aperture of the inlet of the tub.

34. A humidifier assembly according to claim 33, wherein the face seal is conformable along an axis of the inlet of the tub.

35. A humidifier assembly according to claim 34, wherein the face seal is flexible, upwards, downwards, and/or sideways, angularly, pivotally, and/or rotationally to accommodate misalignment and/or manufacturing tolerances.

36. A humidifier assembly according to claim 34, wherein the face seal is conformable and flexible within a predetermined range.

37. A humidifier assembly according to claim 36, wherein the face seal is axially and/or laterally flexible within a range of about 1-5 mm.

38. A humidifier assembly according to claim 37, wherein the face seal is configured to form a seal with the inlet of the tub even if the axis of the connector is not aligned with the axis of the inlet.

39. A humidifier assembly according to claim 38, wherein the tub includes a baffle adjacent the inlet, the baffle including a curved surface to promote circulation and water pickup.

40. A humidifier assembly according to claim 39, wherein the base plate comprises aluminum.

41. A humidifier assembly according to claim 28, wherein a maximum volume of water is several hundred milliliters.

42. A humidifier assembly according to claim 40, wherein the attaching portion is attached to a structure that receives a flow of breathable gas from the flow generator.

43. A humidifier assembly according to claim 42, wherein the face seal comprises a pressure-activated seal.

44. A humidifier assembly according to claim 43, wherein the attaching portion of the connector is removably attached to the structure that receives the flow of breathable gas from the flow generator and the flexible sealing portion protrudes therefrom, the inlet of the tub being positioned adjacent to or abutting the face seal such that when pressurized air flows out through the outlet of the flow generator, the face seal fills with air and establishes a pressurized face seal with the inlet of the humidifier tub.

45. A humidifier assembly according to claim 44, wherein the face seal is spaced from the inlet of the tub, in an initial position, and, as pressurized air flows into the tub, the face seal fills with air and expands into engagement with an axially facing surface of the inlet of the tub.

46. A humidifier assembly according to claim 44, wherein the face seal of the flexible sealing portion has approximately 2 mm to 3 mm interference from a nominal contact point to ensure sufficient contact when the inlet of the tub and the connector make contact on each other.

47. A CPAP device including:

a flow generator to generate pressurized gas in the range of 4-28 cm H₂O; and

the humidifier assembly of claim 28.

48. A CPAP device according to claim 47, further comprising a structure in communication with the flow generator and the humidifier assembly, the attaching portion of the connector being connected to the structure.

49. A CPAP device according to claim 48, wherein the cradle is structured to support the humidifier tub in an operative position with respect to the flow generator.

50. A CPAP device according to claim 49, wherein the cradle is structured to push the humidifier tub downwards onto the heater plate.

51. A CPAP device according to claim 50, further comprising a spring to bias the heater plate and the base plate into firm thermal contact with one another.

52. A CPAP device according to claim 51, wherein the cradle includes a securing catch that lifts up and down to enable release or insertion of the humidifier tub.

53. A CPAP device according to claim 52, wherein the securing catch is hinged to a main body of the cradle.

55. A CPAP device according to claim 53, wherein the catch is structured to prevent access to the heater plate when the tub is inserted, including access to the front of the heat conducting base plate.

56. A CPAP device according to claim 53, wherein the cradle includes upstanding side walls to engage sides of the tub upon sliding insertion of the tub into the cradle when docking.

57. A CPAP device according to claim 56, wherein the side walls include generally planar surfaces.

58. A CPAP device according to claim 57, wherein gaps between the sides of the tub and the cradle are dimensioned to be smaller than the size of a finger.

59. A CPAP device according to claim 53, wherein the catch is structured to provide a clicking sound when the tub is properly docked thereby providing audio and/or tactile feedback.

54. A CPAP device according to claim 54, wherein the catch includes a stop positioned in front of the tub when the catch is closed to retain the tub in place.

60. A CPAP device comprising:

a humidifier tub including a heat conducting base plate; and

a cradle to support the humidifier tub in an operative position, the cradle including a heater plate in communication with the heat conducting base plate of the humidifier tub in use, the cradle further including retaining structure to retain the humidifier tub in the cradle, wherein the retaining structure includes a hinged securing catch that lifts up and down to enable release or insertion of the humidifier tub and lateral portions to provide downwardly directed force to ensure good thermal contact between the base plate of the tub and the heater plate.

61. A CPAP device according to claim 60, wherein the retaining structure includes at least one spring that forces the base plate into engagement with the heater plate.

62. A CPAP device according to claim 61, further including a one piece face seal provided adjacent an inlet of the tub, the face seal having an attaching end and a flexible, compliant sealing portion to contact a planar surface of the tub surrounding the inlet of the tub upon docking the tub relative to the cradle.

63. A CPAP device according to claim 62, further comprising a flow generator in communication with the humidifier tub.

64. A CPAP device according to claim 63, wherein the flow generator includes a motor having a motor outlet in communication with a flow generator outlet.

65. A CPAP device according to claim 64, wherein an axis of the motor outlet is oriented to be offset with an axis of the flow generator outlet.

66. A CPAP device according to claim 65, further comprising a spill-back chamber positioned in front of the inlet of the tub, to store a predetermined amount of water that may be inadvertently introduced toward the flow generator outlet from the humidifier.

67. A CPAP device according to claim 66, wherein the predetermined amount of water is about 100 ml.

68. A CPAP device according to claim 60, wherein the retaining structure receives sides of the of the humidifier tub upon initial insertion of the humidifier tub into the cradle and initially directs the heat conducting base plate over the heater plate and directs the heat conducting base plate into contact with the heater plate upon full insertion of the humidifier tub in the cradle.

69. A CPAP device, comprising:

a flow generator to generate pressurized gas in a range of 4-28 cm H₂O;

a humidifier assembly to humidify the pressurized gas flow, the humidifier assembly comprising

a tub to store liquid and including an inlet to receive the pressurized gas flow and direct the pressurized gas flow into contact with the liquid, a heat conducting base plate provided to a bottom portion of the tub, and an outlet to deliver the humidified pressurized gas flow, and

a cradle to support the tub in an operative position to receive the pressurized gas flow, the cradle including a heater plate in contact with the heat conducting base plate of the humidifier tub in the operative position, a retaining mechanism to retain the tub in the cradle and to bring the base plate into engagement with the heater plate, and a spring to bias the heater plate and the base plate into firm thermal contact with one another; and

a connector including an inlet to receive the pressurized gas flow from the flow generator, an outlet to deliver the pressurized gas flow to the inlet of the tub, and a conforming, bellows-type seal to seal the inlet of the tub when the tub is in the operative position and a pressurized gas flow is in the connector.