Patent Application
20250170350
The present invention relates to the methods and devices for the treatment of airway disorders using positive airway pressure.
The following discussion of the background of the invention is merely provided to aid the reader in understanding the invention and is not admitted to describe or constitute prior art to the present invention.
Positive airway pressure (PAP) therapy is a generic term applied to treatments using a stream of air at greater than atmospheric pressure to support airway and pulmonary patency. Typical PAP therapy involves a portable machine that directs pressurized room air into the airway through a tube connected to a face mask. This positive airflow helps keep the airway open. The most familiar application of PAP therapy is preventing the collapse that occurs during sleep apnea, thus allowing normal breathing.
There are various types of PAP therapy that may be employed. Continuous positive airway pressure (CPAP) is a type of PAP therapy in which the air flow is introduced into the airways to maintain a continuous pressure to constantly stent the airways open, in people who are breathing spontaneously. In bilevel positive airway pressure (BiPAP), the air pressure cycles between two levels of pressure based on whether the patient is inhaling or exhaling, but positive pressure is delivered continuously at some level. These pressures are known as inspiratory positive airway pressure (IPAP) and expiratory positive airway pressure (EPAP).
The pressures involved are typically recited in terms of centimeters of water pressure (cm H2O) because lung pressure is often expressed in those units. 1 cm H2O is the amount of pressure required to raise a column of water 1 cm in height. This is equal to 98.07 Pascals. The pressures utilized in PAP therapy are generally between 2 and 30 cm H2O. Various interfaces are available for the delivery of PAP and most can be divided into 3 categories: nasal masks which cover the nose and leave the mouth free; nasal pillows which insert directly into the nostrils; and oronasal (i.e., full face) masks, which cover the nose and the mouth. These interfaces are collectively referred to herein as “face masks.”
Despite the high efficacy of PAP to reverse upper airway obstruction in sleep apnea, treatment effectiveness is limited by variable adherence to prescribed therapy. When adherence is defined as greater than 4 hours of nightly use, 46 to 83% of patients with obstructive sleep apnea have been reported to be nonadherent to treatment. Evidence suggests that use of PAP for longer than 6 hours decreases sleepiness, improves daily functioning, and restores memory to normal levels. The decision to embrace PAP occurs during the first few days of treatment. Typical reasons cited for non-compliance are claustrophobia from the face mask, inability to tolerate compressed air flow and pressure, noise, poor face mask fit/leaks, difficulty sleeping with the device and its long mask connecting hose, and co-sleeping partner disruption. No single factor has been consistently identified as predictive of adherence.
It is an object of the invention to provide a body-worn PAP system providing proper mask fitment during body movement, reduced leakage, and elimination of a need for a connecting hose to the blower unit. It is a second object of the invention to provide a PAP blower adapted for use in a PAP system with a compact noise reduction system that does not need acoustic foams in the airflow path.
In a first aspect, the invention relates to a flow generator adapted for use in a PAP system. The flow generator comprises:
As is apparent from the foregoing, according to the present invention, the air path comprises a plurality of flow straighteners, each followed by an associated chamber volume, between the first chamber proximal to the air inlet aperture and the chamber comprising a blower. Each chamber volume following a flow straightener is an unoccupied space in the air path. In certain embodiments, the flow straighteners occupy between 50% and 99% of the volume of the air path between the air inlet aperture and the fourth (blower) chamber, without accounting for the volume contained in the array of parallel air passages (meaning, considering the flow straighteners as if the parallel air passages did not exist and the flow straighteners were simply solid blocks). There may be 1, 2, 3, 4, 5 or more flow straighteners arranged in a serial fashion, each interleaved by an associated chamber. The volume of the chamber between flow straighteners is determined by the spacing between flow straighteners. This spacing may be as small as 0.1 mm to several centimeters. Each air straightener is preferably at least 18 mm in length as measured along the air passages.
In certain embodiments, the flow generator comprises one or more additional flow straighteners in the air path prior to the fourth chamber. By way of example only, then, the flow generator comprises:
In certain embodiments, there are one, two, three, or more of the additional flow straighteners in the air path. In preferred embodiments, the flow generator comprises:
The air passages in the flow straighteners are preferably linear or substantially linear. By “substantially linear” is meant an air passage which deviates from linear by no more than 20% and may curve in a smooth manner that lacks an edge or a sudden angular change of direction.
In certain embodiments, each of the air passages in the flow straighteners are substantially identical in cross-section. The shape may be any shape, although a substantially hexagonal cross-section is preferred. In certain embodiments, one or more, and in certain embodiments all, air passage in a flow straightener is substantially “in line” with a corresponding air passage in the ajoining flow straightener, meaning that a single linear axis can traverse the two corresponding flow straightener. Regular arrays of 6 or 7 hexagonal holes with an approximate 3 mm side to side dimension across the flats, arranged as shown in the figures are preferred examples.
In certain embodiments, the plurality of flow straighteners alternate in hole number. By way of example, if the first flow straightener may comprise 7 air passages, the second flow straightener would comprise 6 air passages, and the third flow straightener would comprise 7 air passages, resulting in a 7-6-7 alternating pattern of (preferably hexagonal) air passages in the three flow straighteners. In these embodiments, one or more of the air passages are substantially “in line” with corresponding air passages in the ajoining flow straightener, while at least one air passage in the “7” flow straightener is not in line with a corresponding air passage in the ajoining “6” flow straightener
In various embodiments, a flow generator of the present invention has at least one, and preferably 2, 3, 4, 5, or all, of the following characteristics:
These dimensions may be scaled as appropriate, for example based on the size and/or air output of the blower selected. Preferably, these dimensions are not substantially altered in a manner that would substantially increase flow resistance through the device, for example by reducing the cross sectional area of the flow channels.
In certain embodiments, the central axis of the air path from the chamber volume after all the air straightener elements diverges from the central axis of the air path from the first flow chamber to the third flow chamber, meaning that the air flow follows a path into the chamber containing the blower element does not lie on the same single linear axis as the path traversed through the flow straighteners. By way of example, air which reaches the last flow chamber after the air straightener elements may be required to diverge at approximately 90° to the central axis of the air path through the flow straighteners in order to enter the chamber containing the blower element.
As described herein, the airflow through the flow generator preferably does not pass acoustic foam materials between the air inlet aperture and the air output aperture, as such foam may degrade and enter the air flow, thereby being inhaled or ingested by the wearer.
In certain embodiments, the chamber containing the blower element can comprise a resilient liner seated within the chamber, wherein the blower is adapted to seat in a soft and flexible raised retaining feature integrally or unitarily formed on a surface of the resilient liner. This resilient liner acts to both retain and cushion the blower from damage due to handling or dropping of the flow generator during manufacture, shipping, storage, or use. In preferred embodiments, the resilient liner is configured to conform to the shape of the chamber such that it is retained within the chamber without any adhesive. Such embodiments simplify manufacture of the flow generator.
In a second aspect, the invention provides a PAP system adapted for treatment of an individual having respiratory disease, sleep disordered breathing, or requiring breathing support, comprising:
In certain embodiments, the PAP system comprises the flow generator as described in the first aspect.
The PAP system described herein may utilize any face mask known in the art as part of the mask interface. In certain embodiments, the face mask comprises a pair of nasal pillows adapted for at least partial insertion into the nares of the individual. In certain embodiments, the face mask is as depicted in
In embodiments where the bracket projects from the flow generator, the bracket preferably comprises a chin cup adapted to conform approximately to the shape of the mental protuberance. In certain embodiments, a chin cup insert which is adapted to form a cushioned contact surface between the chin cup and the mental protuberance forms a patient contact surface on the chin cup. A battery power supply may be integrated within the flow generator housing, however this power supply may be a separate component from the flow generator and connected by a cable providing an electrical connection between the power supply and the flow generator, or may also be located in close proximity to the flow generator housing and connected via a short lead. When the power supply is provided as a separate component, it may be in the form of a battery pack or as a connection to a mains power source (e.g., a plug-in transformer that receives 120 v mains power and provides DC voltage to the flow generator.
In embodiments where the bracket projects from the power supply, the power supply may be attached to an external surface of the flow generator housing such that the mass of the power supply is supported on and as close as possible to the mental protuberance. In certain embodiments, the flow generator is permitted to “float” relative to the power supply, thereby reducing movement of the flow generator (and so the patient interface) during movement of the wearer by reducing the torque generated by the relatively heavy batteries within the power supply.
In certain embodiments, the PAP system of the invention is configured to be a completely body-worn system. Preferably, the power supply comprises a battery as the source of electrical power to the flow generator. Most preferably, the energy usage of the PAP system can provide a continuous on-demand 10 cm H2O pressure for at least 10 hours through a CPAP face mask. For comfortable use during sleep, this completely body-worn system preferably weighs less than 0.5 kg in use.
In one aspect, then, the invention provides a PAP system adapted for treatment of an individual having respiratory disease, sleep disordered breathing, or requiring breathing support, comprising:
In another aspect the invention provides a PAP system adapted for treatment of an individual having respiratory disease, sleep disordered breathing, or requiring breathing support, comprising:
In another aspect, the invention provides a PAP system adapted for treatment of an individual having respiratory disease, sleep disordered breathing, or requiring breathing support, comprising:
In certain embodiments, the PAP system comprises the flow generator as described in the first aspect.
Most preferably, the energy usage of the PAP system can provide a continuous on-demand 10 cm H2O pressure through a CPAP face mask. For comfortable use during sleep, this completely body-worn system weighs less than 0.3 kg in use without an attached battery.
In a related aspect, the present invention relates to methods of treating sleep apnea, snoring, or another breathing disorder in an individual, comprising:
The present invention provides wearable PAP systems for providing positive air pressure, particularly for use in Continuous Positive Airway Pressure (CPAP) devices, bilevel pressure support devices (BiPAP) devices and related respiratory support devices. As described hereinafter, the present systems provide simple and inexpensive assembly with mass-producible parts. The design effectively isolates offensive noise and vibration from being transmitted to the wearer of the device without the use of acoustic abatement foams that can contaminate the air pathway and be subsequently inhaled or ingested by the user. Including any batteries required for operation, the systems of the invention preferably weigh less than 0.5 kg and the device housing, excluding the nasal prongs assembly, protruding chin cup and supporting headgear assembly (subject to separate disclosures), can be as small as approximately 96 mm by 101 mm by 73 mm.
Prior wearable CPAP devices mounted on the head or face of a user have been unsuccessful primarily because of the amount of noise and vibration transmitted directly to the skull of the user. They were also heavy and uncomfortable to wear. The new invention described herein provides the following advantages:
The system housing contains a small CPAP blower, which is preferably about 51 mm in diameter by about 33 mm in height, drive and control electronics for the blower. A compact air inlet path from outside the device to the inlet hole of the blower that contains a set of defined resonant chambers and unique air straightening elements that provide a radiated blower noise of less than 32 dBA at 1 meter when operating at 10 cm H2O pressure through a CPAP face mask.
In certain embodiments, the system comprises a removable rechargeable battery pack (e.g., containing four cylindrical 3600 mAh rechargeable batteries or 3 or more 5000 mAh rechargeable batteries) which provides electrical power to the drive control electronics and the blower. The batteries may be charged or supported in a wired or wireless manner. Alternatively, or together with the battery pack, the system comprises a connection to mains power which can provide electrical power to the drive control electronics and the blower, and/or provide electrical power for charging the batteries. In the case that there is no battery pack, the use of mains power or an external battery can provide a much lighter wearable device, albeit providing a system which is not entirely body worn due to the wired power connection.
Bracket 1, also referred to herein as a “chin cup,” further isolates the blower noise and vibration from the wearer, is used to mount the system on the user. The chin cup includes a resilient insert that provides comfort during extended wear and a secure fit for users with different chin sizes/shapes and chin positions. The chin cup insert has a rolling edge in contact with the wearer's chin (like a CPAP face mask) to avoid causing discomfort and red marks from pressure point edges of conventional pads. The insert is preferably made from biocompatible silicone and uses push fit pins on its base to ensure correct orientation in the chin cup holder as well as easy assembly/disassembly for cleaning. The chin cup and/or device housing may also uniquely contain biometric sensors in near or complete contact with the user to monitor vital parameters such as pulse-oximetry, breathing/other body sounds, body position/movement, temperature and so on. The chin cup insert is preferably of 50 to 75 durometer (A) with a flange wall thickness of approximately 1 to 2 mm. The chin cup insert is typically at least 6 mm high with a flange typically at least 6 mm wide. The elliptical hole in which the chin is inserted is typically 35 to 60 mm long and 20 to 30 mm wide. This central hole allows ventilation and cooling of the chin area which would not be feasible with a solid contact area. This chin cup design is readily applicable to other applications requiring lengthy contact times with a user such as for securing helmets and so on.
The construction can be manufactured using plastic injection molded parts which maintain accurate dimensions which are easily assembled. The system is thermally and electrically efficient with low noise and with low resistance to airflow, providing a current draw that increases from about 0.28 Amps to about 0.33 Amps at an inlet voltage of 14.8 V or 0.35 to 0.41 Amps at an input voltage of 11.1V when the noise abatement measures are added to the blower, and operating at 10 cm H2O outlet pressure through a PAP face mask. The device can be used for over 10 hours at a continuous 10 cm H2O pressure.
This system design described herein lends itself to other applications requiring small size, low noise, light weight, low heat production and low power consumption provided by batteries. One application would be in hazardous environment breathing equipment requiring powered airflow through filtering/cleansing media. Another application could be in high filtration allergy masks for acutely sensitive people. Other wearable applications would include devices for pumping fluids to advantageously compress or decompress parts of the body. While depicted herein as a chin-mounted system, the systems of the present invention could also be incorporated into a respiratory face mask, worn on top of the head, or on a user's chest or shoulder. In configurations where the face mask is not integral to the housing, the blower could, for example, be connected to a respiratory face/nasal mask or nasal prongs via tubing or other means. But by locating such a wearable blower device close to the user's face the use of uncomfortable, long, annoying and high resistance connection hoses can be avoided.
As described herein and shown in
The air travels from first chamber 21 along a linear path through the first air straightener 13 and into a second chamber 22 which is again a substantially rectangular cuboid shape. The peripheral walls of the air straightener 13 that contact the lower enclosure 2 are constructed so that the exterior thereof fit the shape of the enclosure walls so that air straightener 13 may be sealed in an airtight manner into the lower enclosure 2. This first air straightener 13 comprises an array of parallel air passages as described herein. The air passages define a void volume of air straightener 13, meaning the portion of the air straightener through which the air may pass to reach the second chamber 22. A second air straightener 13 that is substantially identical to the first air straightener 13 follows the second chamber 22. Air travels through this second air straightener and into a third chamber 23. As depicted in
During operation, the PAP system creates positive air pressure through patient interface 37. As depicted in
In certain embodiments, pressurized air is delivered to a patient through patient interface 37 at a working pressure ranging from approximately 2 cm H2O to approximately 30 cm H2O above atmospheric pressure at the point of use, although any appropriate pressure may be used. Exhaust ports in the form of holes 42 are designed to prevent carbon dioxide build-up in the face mask and may be of appropriate configurations to reduce the exhaust noise. During inspiration, air from the PAP system that has accumulated at the working pressure in the hollow chamber is inhaled. During expiration, exhaled gas of the approximate volume of the patient interface 37 is deposited in the mask, with the rest exiting through the vent holes 42 or through the blower 8 itself. The continuous flow of air from the PAP system can also wash exhaled air out the patient interface 37 through these exhaust ports before the next inspiration.
Conventional PAP interfaces try to be as low profile and unobtrusive as possible and are held in place by directly attached headgear or straps and are connected to the CPAP unit by a long hose or hoses. Conversely, patient interface 37 is held in place directly by an upward force from the chin-mounted wearable PAP unit and uses no connection hose. Eliminating the high resistance connecting hose reduces the breathing resistance on exhalation through to the blower, making breathing more comfortable. Hose connections and changes in air flow direction and cross-sectional areas between a conventional CPAP unit and the user's face mask also provide discontinuities that affect the smooth flow of air between the CPAP unit and the face mask, and so result in additional sources of noise. By eliminating the connecting hose and other discontinuities, these additional noise sources are also eliminated reducing noise transmitted to both the user and the user's bed partner. Patient interface 37 has minimal abrupt geometry changes in the airflow path to minimize turbulence and noise, and is quieter than a conventional interface. This allows one embodiment of the interface design with vent holes 42 to be at least 2 dBA quieter than a conventional PAP interface. Also, when a compressible bellows section similar to that found in nasal pillows was inserted between the nares and the PAP unit of the invention, the interface was noisier than the smooth bulbous design of patient interface 37. It can be recognized that the interface can be larger or smaller as required to fit different nose sizes/shapes and accommodate different distances between the PAP system and a user's nose. As well as dissipating noise, the compliance of patient interface 37 acts as a compressible compliance buffer between the nose and the PAP system, so as to avoid the user's nose contacting the hard housing surfaces. To ensure comfort, fit, seal and compliance, the interface is preferably made from a 40 to 70 durometer biocompatible silicone (ideally 50 to 60) but higher and lower durometers and different materials may also be substituted.
A detailed drawing of one example of patient interface 37 is provided in
The exhaust holes 42 are preferably located on the bottom of the interface to exhaust air away from the user's face and not towards a bed partner. This location helps to minimize turbulence and noise in the interface and lines up directly with the exhaled air from the user. Exhaust holes 42 can be approximately 1.5 to 2.0 mm in diameter, but this arrangement and hole size can be varied as appropriate using known art to give the desired air exhaust flow and to minimize exhaust noise.
If humidification of the delivered air is required, a conventional hygroscopic condenser humidifier heat and moisture exchanger element can be inserted between the PAP unit blower and the patient's nares.
Up to 30% of current PAP users require a full-face or nose-mouth interface to deal with air/pressure leaks through their mouth. This is mitigated somewhat by the use of a head strap system to pull the PAP unit up on the user's chin, thereby assisting the user's mouth to stay shut and not leak air/pressure. If necessary, mouth leaks could be further eliminated by using an integrated nose/mouth interface instead of the nose-only interface described above.
As discussed above, the energy supply for the PAP system may be internal to the body of the system (e.g., in the form of a battery pack), or may be located externally to the device housing. In
Children in particular often suffer with unstable, poorly-fitting, large claustrophobic face masks tied to a heavy hose connecting the mask to a bedside PAP unit. The external power supply could be connected to the lighter wearable PAP unit 201 using a spiral cable like a coiled telephone handset cable. This would allow the cable to maintain a short unobtrusive length under many conditions but be readily and easily extendable to accommodate user movements and changes of sleeping position. Such cables are light and robust, and able to withstand long-term bending and stretching in use. This device configuration without an internal battery would also be useful in hazardous environment breathing equipment requiring high pressures for long periods of time.
In an analogous manner to
In still another exemplary embodiment,
Exemplary PAP device 301 is shown in exploded form in
In an analogous manner to
Exemplary PAP device 401 is shown in exploded form in
The following are preferred embodiments of the invention.
Embodiment 1. A flow generator adapted for use in a PAP system, comprising:
Embodiment 2. A flow generator according to embodiment 1, comprising:
Embodiment 3. A flow generator according to embodiment 1, comprising:
Embodiment 4. A flow generator according to embodiment 3, wherein the spacing between the first and second flow straighteners and the spacing between the second and third flow straighteners are each independently between 0.1 and 0.3 mm, and
Embodiment 5. A flow generator according to embodiment 3 or 4, wherein the first flow straightener comprises seven air passages, the second flow straightener comprises six air passages, and the third flow straightener comprises seven air passages, resulting in a 7-6-7 pattern of preferably hexagonal air passages in the three flow straighteners, wherein one or more of the air passages in each flow straightener are substantially “in line” with corresponding air passages in an ajoining flow straightener, and at least one air passage in the “7” flow straightener is not in line with a corresponding air passage in the ajoining “6” flow straightener.
Embodiment 6. A flow generator according to one of embodiments 1-5, wherein each air passage in the plurality of flow straighteners are substantially identical in cross-section.
Embodiment 7. A flow generator according to one of embodiments 1-6, wherein each air passage in the plurality of flow straighteners are substantially hexagonal in cross-section.
Embodiment 8. A flow generator according to embodiment 2, having at least one of the following characteristics:
Embodiment 9. A flow generator according to embodiment 8 having each of characteristics i) through vi).
Embodiment 10. A flow generator according to one of embodiments 1-9, wherein one or more air passages in each of flow straightener in the plurality is in line with a corresponding air passage with the other flow straighteners in the plurality.
Embodiment 11. A flow generator according to one of embodiments 1-10, wherein the central axis of the air path through the plurality of flow straighteners is approximately linear, and the central axis of the air path from the chamber following the final flow straightener in the plurality to the blower chamber diverges from the central axis of the air path from the first flow chamber to the third flow chamber.
Embodiment 12. A flow generator according to embodiment 11 wherein the divergence is approximately 90° to the central axis of the air path through the plurality of flow straighteners.
Embodiment 13. A flow generator according to one of embodiments 1-12, wherein the airflow through the flow generator does not pass through a foam material between the air inlet aperture and the air output aperture.
Embodiment 14. A flow generator according to one of embodiments 1-13, wherein the blower chamber comprises a resilient liner, wherein the blower is adapted to seat in a raised retaining feature integrally or unitarily formed on a surface of the resilient liner.
Embodiment 15. A PAP system adapted for treatment of an individual having respiratory disease, sleep disordered breathing, or requiring breathing support, comprising:
Embodiment 16. A PAP system according to embodiment 15, wherein the bracket projects from the flow generator and the power supply is integrated within the flow generator housing.
Embodiment 17. A PAP system according to embodiment 15, wherein the wherein the bracket projects from the power supply, and the power supply is attached to an external surface of the flow generator housing.
Embodiment 18. A PAP system according to embodiment 15, wherein the wherein the bracket projects from the flow generator, and the power supply is separate from the flow generator and connected by a cable providing an electrical connection between the power supply and the flow generator.
Embodiment 19. A PAP system according to embodiment 18, wherein the power supply operably connects to a mains power source.
Embodiment 20. A PAP system according to one of embodiments 15-19, wherein the face mask comprises a pair of nasal pillows adapted for at least partial insertion into the nares of the individual.
Embodiment 21. A PAP system according to one of embodiments 15-20, wherein the bracket projecting from the flow generator comprises a chin cup adapted to conform approximately to the shape of the mental protuberance, and a chin cup insert which is adapted to form a cushioned contact surface between the chin cup and the mental protuberance.
Embodiment 22. A PAP system according to one of embodiments 15-21, wherein the flow generator is according to one of embodiments 1-14.
Embodiment 23. A PAP system according to one of embodiments 15-22, wherein the power supply comprises a battery, and wherein the PAP system is configured to provide a continuous 10 cm H2O pressure and 76 L/min flow rate for at least 10 hours.
Embodiment 24. A PAP system according to one of embodiments 15-23, wherein the PAP system weighs less than 0.5 kg in use.
Embodiment 25. A PAP system according to one of embodiments 15-24, wherein the face mask is in the form of a resonant chamber formed from a resilient material which embraces the nose without insertion into the nares.
Embodiment 26. A PAP system according to one of embodiments 15-25, wherein the face mask is in the form of a hollow body comprising an inner chamber and formed of a resilient material forming a c-shaped cavity configured to receive a patient's nose and to form a seal against the patient's nose, and one or more air outlet openings through the hollow body within the c-shaped cavity configured to direct air flow entering the hollow body from the PAP system towards the nares of the patient.
Embodiment 27. A face mask adapted for use with a PAP system, comprising:
Embodiment 28. A face mask according to embodiment 27, further comprising one or more vent holes through the hollow body configured to permit air to exhaust from the inner chamber into the atmosphere.
Embodiment 29. A method of treating sleep apnea, snoring, or another breathing disorder in an individual, comprising:
Embodiment 30. A PAP system adapted for treatment of an individual having respiratory disease, sleep disordered breathing, or requiring breathing support comprising a flow generator configured to engage onto the mental protuberance of the individual's mandible and be retained thereon by head straps.
Embodiment 31. A PAP interface comprising:
The radiated sound pressure level and airflow produced by a prototype PAP system of the invention operating at 10 cm H2O was measured at a distance of 1 m substantially as described in ISO 17510:2015 exhausting through a 0.179 inch plate orifice versus a commercially available ResMed Air Mini system is shown in Figure XXX.
Sound pressure values of a variety of objects are listed below.
The following table shows the flow performance of an embodiment of the invention shown in
This following table compares the radiated noise and delivered air flow attributes of two embodiments of the invention versus a commercially available ResMed Air Mini bedside CPAP device. Noise was measured at 1.0 m from blower unit exhausting through 0.18 inch plate orifice at end of 6 foot hose facing away from a sound meter microphone. Ambient Conditions—89° F., 1420 feet elevation, 20-22 dBA sound. The A2 unit is a system of the present invention powered by an external power supply and the B2 unit is similar system powered by a 3 cell lithium ion battery integrated into the device housing. The flow and noise characteristics are very similar when tested under identical conditions.
To gather real-world data on the acceptance of the PAP system of the invention by CPAP users, test subjects were asked to wear the PAP system and answer a series of questions. The following reports those results.
In the present tests, ambient sound was approximately 20 dB(A). The present devices comprise a compact air inlet path from outside the device to the inlet hole of the blower that contains a set of defined resonant chambers and flow straightening elements that provide a radiated blower sound pressure of about 32 dB(A). Under similar measurement conditions, the blower isolated from the acoustic dampening provided by the device elements was 44 dB(A).
All dimensions recited in the present application are exemplary only, and may be modified in accordance with the teachings of the invention. The terms “about” or “approximately” as used herein with regard to any value is +/−1% to 10% of the value. In preferred embodiments this may be +/−10% of the value, +/−5% of the value, or +/−2% of the value.
The present invention and the various features and advantageous details thereof are explained more fully with reference to the non-limiting embodiments that are illustrated in the accompanying drawings and detailed in the following description. It should be noted that the features illustrated in the drawings are not necessarily drawn to scale. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the present invention. The examples used herein are intended merely to facilitate an understanding of ways in which the invention may be practiced and to further enable those of skill in the art to practice the invention. Accordingly, the examples should not be construed as limiting the scope of the invention. In the drawings, like reference numerals designate corresponding parts throughout the several views.
Those skilled in the art will appreciate that the conception upon which this disclosure is based may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention.
One skilled in the art readily appreciates that the present invention is well adapted to carry out the objects and obtain the ends and advantages mentioned, as well as those inherent therein. The examples provided herein are representative of preferred embodiments, are exemplary, and are not intended as limitations on the scope of the invention.
It will be readily apparent to a person skilled in the art that varying substitutions and modifications may be made to the invention disclosed herein without departing from the scope and spirit of the invention.
All patents and publications mentioned in the specification are indicative of the levels of those of ordinary skill in the art to which the invention pertains. All patents and publications are herein incorporated by reference to the same extent as if each individual publication was specifically and individually indicated to be incorporated by reference.
The invention illustratively described herein suitably may be practiced in the absence of any element or elements, limitation or limitations which is not specifically disclosed herein. Thus, for example, in each instance herein any of the terms “comprising”, “consisting essentially of” and “consisting of” may be replaced with either of the other two terms. The terms and expressions which have been employed are used as terms of description and not of limitation, and there is no intention that in the use of such terms and expressions of excluding any equivalents of the features shown and described or portions thereof, but it is recognized that various modifications are possible within the scope of the invention claimed. Thus, it should be understood that although the present invention has been specifically disclosed by preferred embodiments and optional features, modification and variation of the concepts herein disclosed may be resorted to by those skilled in the art, and that such modifications and variations are considered to be within the scope of this invention as defined by the appended claims.
Other embodiments are set forth within the following claims:
The present application claims the benefit of U.S. Provisional Application 63/261,200, filed Sep. 14, 2021, and U.S. Provisional Application 63/316,351, filed Mar. 3, 2022, each of which is hereby incorporated in its entirety and from each of which priority is claimed.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/US2022/043556 | 9/14/2022 | WO |
| Number | Date | Country | |
|---|---|---|---|
| 63261200 | Sep 2021 | US | |
| 63316351 | Mar 2022 | US |
