HUMIDIFIER WITH STRUCTURE TO PREVENT BACKFLOW OF LIQUID THROUGH THE HUMIDIFIER INLET
A humidifier includes a base configured to retain a body of liquid therein, a top cover, and a seal disposed between the top cover and the base. At least a portion of the base is constructed of a heat conducting material. The top cover defines both an inlet and an outlet communicated with an interior of the base. The inlet is configured to receive pressurized breathable gas and the outlet is configured to deliver the pressurized breathable gas with added humidity.
This application is a continuation of Ser. No. 10/467,382, filed 7 Aug. 2003, now U.S. Pat. No. 6,935,337, which is the US national phase of international application PCT/AU02/00155 filed 14 Feb. 2002, which designated the United States, and claims the benefit of Australia Application Nos. PR3117, filed Feb. 16, 2001, and PR 7288, filed Aug. 27, 2001, each of which is incorporated herein by reference in its entirety.
The present application claims priority to Australian Provisional Applications PR3117, filed on Feb. 16, 2001 and PR7288, filed on Aug. 27, 2001, the specifications and drawings of which are incorporated by reference in their entireties.
The present invention relates to a humidifier for use with an apparatus for supplying breathable gas such as those used for Non-invasive Positive Pressure Ventilation (NIPPV) or Continuous Positive Airway Pressure (CPAP).
An apparatus for NIPPV or CPAP typically comprises a blower whose output is connected to a patient interface, such as a mask, via an air delivery conduit. Some patients find NIPPV or CPAP more comfortable when provided with humidified air. To this end, manufacturers often supply humidifiers which may be attached in the air circuit between the blower outlet and the patient interface. Humidifiers typically include a water reservoir and are configured such that ambient air from the blower entering the humidifier collects moisture through contact with the water, before continuing on to the patient interface.
Typically, the blower and humidifier are separate components connected via a flexible conduit. An air delivery conduit connects the humidifier outlet to a patient interface mask. Alternatively, the blower and humidifier may be rigidly-connected together. Air from the blower outlet passes into the humidifier inlet where it is humidified and then passes to the air delivery conduit. A potential problem with either arrangement is that if the humidifier is tilted relative to its normal orientation, water may run or spill from the humidifier into the blower outlet which may damage the electrical circuits of the blower and potentially cause infection control problems.
It is one aspect of the present invention to substantially overcome or at least ameliorate the prior art disadvantages.
It is another aspect to provide a humidifier for a CPAP apparatus that is adapted to substantially prevent liquid contained thereto from undesirably exiting an inlet of the humidifier.
It is another aspect to provide a humidifier that is capable of directly connecting to a CPAP apparatus.
It is another aspect to provide a humidifier that has an inlet that is directly connectable with a CPAP apparatus to effectively eliminate a supply tube.
It is another aspect to provide a humidifier that is capable of heating the liquid contained therein.
One embodiment of the present invention includes an apparatus for humidifying breathable gas including a humidifier body configured to retain a body of liquid therein, an inlet communicated with an interior of the humidifier body and connectable to a blower outlet, and an outlet communicated with the interior of the humidifier body and connectable to a patient supply conduit. The interior of the humidifier is arranged such that liquid from the body of liquid is prevented from exiting the humidifier body through the inlet thereof when the humidifier body is rotated from a working, upright orientation.
In this manner, the liquid is substantially prevented from entering the blower outlet and possibly damaging the blower.
It is contemplated that the apparatus may also include a first chamber having an inlet and an outlet, the first chamber inlet preferably being connectable to a blower outlet, a second chamber having an inlet preferably connected to the first chamber outlet, and an outlet preferably connectable to the patient supply conduit, the second chamber preferably having the carrying capacity for the body of liquid. The first chamber inlet and outlet and volumes of the first and second chambers may be adapted such that, when the humidifier is disposed in the working upright orientation, the body of liquid is contained in the second chamber and, in other relative positions of the humidifier, the body of liquid is retained in at least one of the second chamber and the first and second chambers at a level therewithin below a level of the first chamber inlet.
A volume of the second chamber may be larger than a volume of the first chamber.
The first chamber may be located substantially above the second chamber in the working upright orientation of the apparatus.
The first chamber inlet and outlet may be located adjacent opposing sections of the first chamber.
The second chamber outlet may be located closer to the first chamber outlet than the first chamber inlet.
At least a portion of a base of the second chamber may be made of a heat conducting material.
The heat conductive portion may be in the form of a metallic cap which covers an opening of the base.
The apparatus may also include a top cover, a base, and a divider disposed between the top cover and base, wherein the base defines a receptacle formed therewithin, which preferably retains the body of liquid in the working orientation of the apparatus.
The top cover and the divider together may define the first chamber and the receptacle and the divider together form the second chamber.
The first chamber inlet and the second chamber outlet may be formed in the top cover and is the first chamber outlet and the second chamber inlet may be formed in the divider, the first chamber outlet and the second chamber inlet may be defined by a single aperture in the divider which communicates the first and second chambers.
The divider may define first and second sections, the first section together with the top cover preferably defining the first chamber.
The divider may include a plurality of apertures, separated by ribs, which may provide fluid communication from the second chamber to the second chamber outlet formed in the top cover.
The top cover and the base may be formed from a relatively rigid polymer material and the divider may be formed from a relatively resilient material.
The first chamber inlet may be connected to a blower outlet, the first chamber outlet may be connected to the second chamber inlet, the second chamber outlet may be connected to the patient supply conduit, and a portion of the second chamber below and behind the second chamber inlet may define a volume thereof greater than a volume of the body of liquid.
A portion of the second chamber between the first chamber inlet and the second chamber inlet and below the second chamber inlet may define a volume thereof greater than the volume of the body of liquid.
Portions of the first chamber and second chamber between the first chamber inlet and the second chamber outlet may define a volume thereof greater than the volume of the body of liquid.
Another embodiment of the present invention includes a CPAP apparatus including an apparatus for humidifying breathable gas as described above.
Another embodiment of the present invention includes a humidifier for a CPAP apparatus having a humidifier body defining a fluid reservoir and a fluid passage therein. The humidifier body has first and second chambers with a dividing member therebetween. The dividing member includes an orifice therethrough to communicate the first and second chambers one another. Air from a blower (not shown) arrives in the first chamber via a first chamber inlet and departs from the second chamber via a second chamber outlet. The fluid passage includes the inlet, outlet, the orifice, and at least, portions of the first and second chambers. The humidifier is designed to carry a body of liquid having a maximum volume, Vmax. In a working orientation of the humidifier, the liquid body lies in a bottom portion of the second chamber. With respect to the working orientation o the humidifier the orifice lies forward of and to the side of the inlet. The first and second chambers are configured such that a volume of a first portion of the second chamber, which lies directly beneath the first chamber, is greater than Vmax. Additionally the volume of a second portion of me second chamber, which is disposed to the side of the first chamber, is greater than Vmax. Furthermore, the volume of a portion of the second chamber forward of the inlet plus a portion of the first chamber forward of the inlet is greater than Vmax. Additionally, the volume of a portion of the second chamber to the side of the inlet plus a portion of the first chamber to the side of the inlet is greater than Vmax.
Yet another embodiment of the present invention includes a humidifier for a CPAP apparatus having first and second chambers, wherein an inlet to the humidifier is communicated with the first chamber, an outlet from the humidifier is communicated with the second chamber, and the first and second chambers are intercommunicated via an orifice extending therebetween. The inlet and orifice are arranged relative to one another such that a level of a volume of liquid present within the humidifier is below at least one of the inlet and orifice for any orientation of the humidifier.
Although certain embodiments of the invention are illustrated and described herein as having certain features, one skilled in the art would recognize that alternative embodiments of the invention could be provided based on at least one or more features, either individually or in combination, of the illustrated and described embodiments.
The benefits of the present invention will be readily appreciated and understood from consideration of the following detailed description of embodiments of this invention, when taken with the accompanying drawings, wherein:
In a working orientation represented in
The embodiment of the humidifier 10 shown in
As shown in
Similarly, as shown in
As shown in
As shown in
In the embodiment illustrated in
For each of the orientations of the humidifier 10 shown in
It is also contemplated that the humidifier 30 may include an additional internal passage to allow monitoring of the CPAP pressure without degrading, signal strength or necessitating relatively large correction factors due to signal attenuation within the humidifier, such as described in co-pending Applications incorporated above, as well as co-pending Application No. WO 02/066107. entitled “Air Pressure Signal Monitoring in Apparatus for Treating Sleep Disordered Breathing”, filed on even date herewith and hereby incorporated by reference in its entirety.
As shown in
As shown in
In use, a predetermined maximum volume of liquid is poured into the receptacle 60 of the base 40 after removing the top cover 36 and the sealing gasket 38 from the base 40. The top cover 36 and the sealing gasket 38 are then reattached to the base 40. As shown in
In the working upright orientation of the humidifier 30, as shown in
Similarly as with the embodiment illustrated in
For each of the orientations of the humidifier 30 shown in
In
In
In
The humidifier 30 thus ensures that the body of liquid 78 is disposed in one of (a) only the second chamber 76, or (b) portions of the first and second chambers 74, 76 at a level below the inlet 32, to prevent liquid from exiting through the inlet 32 at orientations of the humidifier 30 up to an angle of about 90° from the working upright orientation. In the illustrated embodiment, a number of features of the humidifier 30 contribute to ensuing this function. These include relive positions of the inlet 32 and first aperture 50. More particularly, the inlet 32 and first aperture 50 are located on opposing ends of this first chamber 74. Also, the volume of the second chamber 76 is larger than the volume of the first chamber 74, which is assisted by the raised portion 48 of the gasket 38 so that liquid displaced from the first chamber 74 ay be accommodated within the second chamber 76 without overflow through aperture 50. Furthermore, the outlet 34 is located closer to the first aperture 50 than the inlet 32, which assists in ensuing that liquid will exit via the outlet 34, rather than through the inlet 32.
The humidifier 30 therefore substantially prevents or reduces the risk of water exiting through the inlet 32, which may damage the NIPPV or CPAP apparatus, when the humidifier 30 is in other orientations up to an angle of about 90° from its working upright orientation.
It is contemplated that the humidifier 30 may be used as a retrofit or add-on component for a CPAP apparatus. To facilitate this usage, it may be preferable to provide a connecting structure 100 that is configured to connect between the CPAP apparatus and humidifier 30. As shown in
To facilitate connection of the humidifier 30 to the connecting strut 100, it is contemplated that another embodiment of a humidifier, indicated at 120 in
As shown in
Referring back to
In certain circumstances, it may be desirable to provide heated humid air to the respirator mask. Accordingly, another embodiment of the connecting structure, indicated at 150 in is
As shown in
Referring to
It is also contemplated that the heating element 162 may be upwardly resiliently biased to ensure adequate contact between the heating element 162 and the heating plate 174.
As shown in
Claims
1.-7. (canceled)
8. A respiratory therapy system for providing humidified respiratory therapy, the respiratory therapy system comprising:
- a respiratory therapy device to administer respiratory therapy to a patient, the respiratory therapy device comprising: a housing; a recess defined on a side of the housing; a heating element positioned on a bottom surface of the recess; a blower unit located within the housing to generate a supply of pressurized breathable gas; an outlet positioned on a sidewall of the housing within the recess, the outlet being in fluid communication with the blower unit and providing the supply of pressurized breathable gas outside of the housing; and a control unit positioned on a top surface of the housing, the control unit including a display and a selecting device to control the respiratory therapy;
- a humidification chamber configured to be positioned in the recess of the housing, to be heated by the heating element, and to add humidification to the pressurized breathable gas from the heating element by warming water contained in the humidification chamber, the humidification chamber comprising: a bottom surface constructed of a heat conductive material, wherein the bottom surface is configured to be positioned over the heating element; a wall extending from the bottom surface and defining a volume to hold the water in the humidification chamber; a top surface, the bottom surface, wall, and top surface together enclosing the volume; an inlet configured to be fluidly connected to the outlet of the respiratory therapy device, the inlet receiving the supply of pressurized breathable gas via the fluid connection with the outlet of the respiratory therapy device; an outlet configured to direct the pressurized breathable gas with added humidity towards an air delivery conduit for providing the respiratory therapy to the patient; and an obstruction within the chamber that is positioned between the bottom surface and the top surface, wherein the obstruction has a maximum horizontal dimension that is greater than a maximum vertical dimension of the obstruction, wherein the obstruction extends at least partially across an interior of the humidification chamber along a horizontal plane.
9. The humidification system of claim 8, wherein the respiratory therapy device further includes a retaining mechanism to retain the humidification chamber in the recess.
10. The humidification system of claim 9, wherein the retaining mechanism comprises a resiliently biased member that is resiliently biased and is deflected during insertion of the humidification chamber into the recess.
11. The humidification system of claim 8, further comprising a retaining mechanism to retain the humidification chamber in the recess, the retaining mechanism being positioned at a front of the respiratory therapy device when the humidification chamber is retained within the recess.
12. The humidification system of claim 11, wherein the retaining mechanism comprises a resiliently biased member that is resiliently biased in a vertical direction.
13. The humidification system of claim 12, wherein the retaining mechanism is vertically deflected during insertion of the humidification chamber into the recess and substantially returns to its resiliently biased positioned upon full insertion of the humidification chamber into the recess.
14. The humidification system of claim 8, wherein the display and the selecting device are positioned above the top surface of the humidification chamber when the humidification chamber is positioned in the recess.
15. The humidification system of claim 8, wherein the obstruction defines, at least partially, one or more fluid inlet passageways between the inlet and the water contained in the humidification chamber, the one or more fluid inlet passageways causing the pressurized breathable gas received through the inlet to be, at least partially, diverted around the obstruction before reaching the water contained in the humidification chamber for added humidification
16. The humidification system of claim 15, wherein the one or more fluid inlet passageways are defined by the obstruction and the top surface.
17. The humidification system of claim 15, wherein the one or more fluid inlet passageways are defined by the obstruction and the wall.
18. The humidification system of claim 15, wherein the one or more fluid inlet passageways are defined by the obstruction, the top surface, and the wall.
19. The humidification system of claim 15, wherein the one or more fluid inlet passageways being at least partially offset from the inlet so as to cause the at least partial diversion of the of the pressurized breathable gas.
20. The humidification system of claim 8, wherein the obstruction further defines, at least partially, one or more fluid outlet passageways between the water contained in the humidification chamber and the outlet, the one or more fluid outlet passageways causing the pressurized breathable gas with added humidification to be, at least partially, diverted around the obstruction before being expelled through the outlet.
21. The humidification system of claim 20, wherein the one or more fluid outlet passageways are defined by the obstruction and the top surface.
22. The humidification system of claim 20, wherein the one or more fluid outlet passageways are defined by the obstruction and the wall.
23. The humidification system of claim 20, wherein the one or more fluid outlet passageways are defined by the obstruction, the top surface, and the wall.
24. The humidification system of claim 20, wherein the one or more fluid outlet passageways being at least partially offset from the outlet so as to cause the at least partial diversion of the of the pressurized breathable gas with added humidification.
25. The humidification system of claim 8, wherein the humidification chamber further includes an internal vertical wall positioned within the interior of the humidification chamber and extending at least partially below the obstruction, wherein the internal vertical wall at least partially obstructs flow of the pressurized breathable gas between the inlet and the outlet.
26. The humidification system of claim 25, wherein the internal vertical wall extends across the interior of the humidification chamber.
27. The humidification system of claim 26, wherein the internal vertical wall divides a portion of the interior of the humidification chamber below the obstruction into an inlet section and an outlet section, wherein the inlet section corresponds to the inlet and the outlet section corresponds to the outlet, the internal vertical wall at least partially obstructing the flow of the pressurized breathable gas between the inlet section and the outlet section.
28. The humidification system of claim 8, wherein the humidification chamber further includes an internal vertical wall positioned within the interior of the humidification chamber and extending at least partially above the obstruction, wherein the internal vertical wall extends across the interior of the humidification chamber.
29. The humidification system of claim 28, wherein the internal vertical wall divides a portion of the interior of the humidification chamber above the obstruction into an inlet section and an outlet section, wherein the inlet section corresponds to the inlet and the outlet section corresponds to the outlet, the internal vertical wall blocks the flow of the pressurized breathable gas from the inlet section to the outlet section causing the pressurized breathable gas to flow around the obstruction.
30. The humidification system of claim 28, wherein the internal vertical wall extends from the top surface of the humidification chamber.
31. The humidification system of claim 8, wherein the humidification chamber is sized and shaped to fit within the recess, wherein positioning the humidification chamber in the recess (i) establishes a fluid connection between the inlet and the outlet of the respiratory therapy device and (ii) positions the bottom surface of the humidification chamber over the heating element of the respiratory therapy device.
32. The humidification system of claim 31, wherein the humidification chamber is configured to be positioned in the recess by horizontally sliding the humidification chamber into the recess.
33. The humidification system of claim 8, further comprising means for removably connecting the inlet of the humidification chamber to the outlet of the respiratory therapy device.
34. The humidification system of claim 8, further comprising: the air delivery conduit, wherein the air delivery conduit is in fluid communication with the outlet of the humidification chamber for transporting the pressurized breathable gas; a patient interface connectable to the air delivery conduit to supply the pressurized breathable gas to the patient; and means removably connecting the air delivery conduit to the patient interface.
35. The humidification system of claim 34, wherein the patient interface further comprises means for securing the patient interface in an operative position to the patient for delivering the respiratory therapy.
36. The humidification system of claim 8, further comprising means for adding water to the humidification chamber.
Type: Application
Filed: Feb 15, 2019
Publication Date: Jul 11, 2019
Inventors: Alexander VIRR (Gosford), Ian Malcolm SMITH (Sydney), Perry David LITHGOW (Sydney), Richard Llewelyn JONES (Hornsby Heights), Andrew CHEUNG (Sydney)
Application Number: 16/277,660