(12) INTERNATIONAL APPLICATION PUBLISHED UNDER THE PATENT COOPERATION TREATY (PCT)
`
`(19) World Intellectual Property
`Organization
`International Bureau
`
`
`
`(43) International Publication Date
`18 March 2004 (18.03.2004)
`
`(10) International Publication Number
`
`WO 2004/022147 A1
`
`(51) International Patent Classification7:
`A62B 9/00
`
`A61M 16/08,
`
`(21) International Application Number:
`PCT/AU2003/001 162
`
`(22) International Filing Date:
`5 September 2003 (05.09.2003)
`
`(25) Filing Language:
`
`(26) Publication Language:
`
`English
`
`English
`
`(30) Priority Data:
`10/235,846
`60/424,695
`60/474,928
`
`6 September 2002 (06.09.2002)
`8 November 2002 (08.11.2002)
`3 June 2003 (03.06.2003)
`
`US
`US
`US
`
`except US):
`(for all designated States
`(71) Applicants
`RESMED LIMITED [AU/AU]; 97 Waterloo Road, North
`
`Ryde, New South Wales 2113 (AU). LJUBOJEVIC,
`Borivoje [AU/AU]; Unit 6/711 Victoria Road, Ryde, New
`South Wales 2112 (AU).
`
`(72)
`(75)
`
`Inventors; and
`Inventors/Applicants (for US only): DREW, Joanne,
`Elizabeth [GB/AU];
`82 Curban Street, Balgowlah
`Heights, New South Wales 2093 (AU). GUNEY, Mem-
`duh [AU/AU]; 52 Eastgate Avenue, Killara, New South
`Wales 2071 (AU). AMARASINGHE, Amal, Shirley
`[AU/AU]; 29 Grace Avenue, Beecroft, New South Wales
`2119 (AU). LITHGOW, Perry, David [AU/AU]; 9 Staff
`Avenue, Glenwood, New South Wales 2768 (AU). GING,
`Anthony, Michael
`[AU/AU]; Unit 5/15 Dover Street,
`Summer Hill, New South Wales 2130 (AU). DARKIN,
`Donald [GB/AU]; 2 Athella Place, Dural, New South
`Wales 2158 (AU). ASTON, Grahame, Bruce [AU/AU];
`21 Rangers Road, Yagoona, New South Wales 2199 (AU).
`
`(54) Title: ELBOW FOR MASK ASSEMBLY
`
`[Continued on next page]
`
`(57) Abstract: An elbow assembly for use in a res-
`piratory mask, which includes an elbow, (160), an
`inlet port (162), an exhaust port (164) and a baffle
`(161) separating the inlet port from the exhaust port.
`A mask assembly includes a cushion (30) comprising
`at least one gusset and an aperture (42) for connec-
`tion to the elbow assembly (20).
`
`
`
`WO2004/022147A1||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||1
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`RMD 1018
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`1
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`RMD 1018
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`

`
`WO 2004/022147 A1
`
`(74) Agents: DAVIDSON, Geoffrey, Robert et al,; Halford &
`C0., Level 7, 1 Market Street, SYDNEY, New South Wales
`2000 (AU).
`
`(81) Designated States (national): AE, AG, AL, AM, AT, AU,
`AZ, BA, BB, BG, BR, BY, BZ, CA, CH, CN, CO, CR, CU,
`CZ, DE, DK, DM, DZ, EC, EE, ES, FI, GB, GD, GE, GH,
`GM, HR, HU, ID, IL, IN, IS, JP, KE, KG, KP, KR, KZ, LC,
`LK, LR, LS, LT, LU, LV, MA, MD, MG, MK, MN, MW,
`MX, MZ, NI, NO, NZ, OM, PG, PH, PL, PT, RO, RU, SC,
`SD, SE, SG, SK, SL, SY, TJ, TM, TN, TR, TT, TZ, UA,
`UG, US, UZ, VC, VN, YU, ZA, ZM, ZW.
`
`(84) Designated States (regional): ARIPO patent (GH, GM,
`KE, LS, MW, MZ, SD, SL, SZ, TZ, UG, ZM, ZW),
`Eurasian patent (AM, AZ, BY, KG, KZ, MD, RU, TJ, TM),
`European patent (AT, BE, BG, CH, CY, CZ, DE, DK, EE,
`ES, FI, FR, GB, GR, HU, IE, IT, LU, MC, NL, PT, RO,
`SE, SI, SK, TR), OAPI patent (BF, BJ, CF, CG, CI, CM,
`GA, GN, GQ, GW, ML, MR, NE, SN, TD, TG).
`Published:
`
`— with international search report
`
`For two—letter codes and other abbreviations, refer to the "Guid-
`ance Notes on Codes andAbbreviations ” appearing at the begin-
`ning of each regular issue of the PCT Gazette.
`
`2
`
`

`
`WO 2004/022147
`
`PCT/AU2003/001162
`
`ELBOW FOR MASK ASSEMBLY
`
`CROSS—REFERENCE TO PRIORITY APPLICATIONS
`
`The present application claims priority to U.S. Provisional Application Serial No.
`
`60/424,695 filed November 8, 2002, U.S. Provisional Application Serial No. 60/474,928 filed
`
`June 3, 2003, and U.S. Non-Provisional Application Serial No. 10/235,846 filed September 6,
`
`2002, which in turn claims priority to U.S. Provisional Application No. 60/317,486 filed
`
`September 7, 2001 and U.S. Provisional Application Serial No. 60/342,854 filed December 28,
`
`2001. Each of the above identified applications is incorporated herein by reference in its
`
`entirety.
`
`BACKGROUND OF THE WVENTION
`
`Field of the Invention
`
`The invention relates to a mask frame and elbow for use with a mask system for Non-
`
`invasive Positive Pressure Ventilation (NPPV) and for continuous positive airway pressure
`
`(CPAP) therapy of sleep disordered breathing (SDB) conditions such as obstructive sleep apnea
`
`(OSA).
`
`2.
`
`Background of the Invention
`
`The use of NPPV for treatment of SDB, such as OSA was pioneered by Sullivan (see,
`
`for example, U.S. Pat. No. 4,944,310, the contents of which are hereby incorporated in their
`
`entirety by reference). Apparatus for this treatment involves a blower which delivers a supply
`
`of air at positive pressure to a patient interface via an air delivery conduit. The patient interface
`
`may take several forms such as nasal masks and nose and mouth masks. Patients must wear a
`
`mask all night while sleeping to receive the therapy.
`
`Masks typically comprise a rigid shell or frame and a soft face-contacting cushion that
`
`spaces the frame away from the face and forms a seal with the patient's face. The frame and
`
`cushion define a cavity which receives the nose, or nose and mouth. The mask is held in
`
`position by headgear, which usually comprises an arrangement of straps that passes along the
`
`side of the face to the back or crown of the head.
`
`3
`
`

`
`WO 2004/022147
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`PCT/AU2003/001162
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`2
`
`Kwok et al. (US. Pat. No. 6,112,746), the contents ofwhich are hereby incorporated in
`
`their entirety by reference, describe a nasal mask and mask cushion. The mask cushion is a
`
`substantially triangularly shaped frame from which extends a membrane. The mask frame has
`
`a scalloped edge by which the mask cushion is affixed to a mask frame. The membrane has an
`
`aperture into which the user’s nose is received. The membrane is spaced away from the rim of
`
`the frame, and its outer surface has substantially the same shape as the rim.
`
`Frater et al. (PCT Patent Application AU01/00746, published as WO 01/97893), the
`
`contents of which are hereby incorporated in their entirety by reference, describes a mask
`
`system for delivering air to a user includes a suspension mechanism to allow relative
`
`movement between a face-contacting cushion and a mask frame. The suspension mechanism
`
`also provides a predetermined force to the cushion that is a function of mask pressure,
`
`displacement of the cushion, or both.
`
`During the course ofthe respiratory cycle patients inhale air, largely comprising a
`
`mixture of nitrogen and oxygen, and exhale a mixture of gases including a relatively higher
`
`fraction of CO2. In a nasal mask system where the patient breathes through the nose, there can
`
`be a build-up of CO2 in the mask cavity which can lead to undesirable CO2 re-breathing.
`
`Hence a variety of vents have been developed for use with masks. The amount of CO2 in the
`
`mask cavity is a function of vent geometry, mask geometry, flow patterns within the mask and
`
`the amount of dead-space within the mask cavity.
`
`The mask is typically joined to the air delivery conduit using a friction fit. Since the
`
`blower is typically placed beside a patient's bed, it is typical that the air delivery conduit be at
`
`least 1 meter long. Occasionally, movement of the air delivery conduit can disrupt the seal.
`
`Furthermore, some patients prefer to have the conduit in one position (for example passing
`
`over their heads), whereas other patients prefer to have it in another position (for example to
`
`the left or right side). Hence swivel elbows were developed for some masks.
`
`Swivel elbows typically include: (i) a cylindrical first portion, having an axis aligned in
`
`a first direction and being adapted for connection to an air delivery conduit; and (ii) a
`
`cylindrical second portion, having an axis aligned in a second direction and being adapted for
`
`connection to a frame of a mask.
`
`4
`
`

`
`wo 2004/022147
`
`PCT/AU2003/001162
`
`3
`
`The first and second directions typically are at right angles to one another. The first
`
`portion has an outer diameter slightly smaller than the inner diameter of typical air delivery
`
`conduit tubing, so that the tubing can overfit the first portion and be held in position by
`
`friction. A free end ofthe second portion is adapted to pass through an orifice in the mask
`
`frame. Such known swivel elbows typically include a vent. While some vents are simply
`
`holes, such as those in the P11ritan~Bennett SOFTFIT mask (Figure 10a), others are more
`
`sophisticated, such as those used with the ResMed ULTRA MIRAGE® mask.
`
`A problem with the prior art swivel elbows incorporating a simple Vent, such as the
`
`Puritan—Bennett SOFTFIT (Figure 10a), the Respironics CONTOUR-DELUXE (Figure 100)
`
`and the related art Tiara ADVANTAGE elbows (Figure 10b), is that air from the blower can
`
`simply short-circuit the mask and pass straight out of the vent. This is a particular problem
`
`when a patient is being given supplemental oxygen, which is expensive. A significant portion
`
`of the oxygen being fed to the elbow simply passes out the vent without entering the mask.
`
`Figures 8a, 8b, 9a, and 9b show prior art elbows manufactured by ResMed Limited for
`the STANDARD and MODULAR masks respectively. Figures 8c, 8d, 9c, and 9d show related
`art elbows manufactured by ResMed Limited for the ULTRA MlRAGE® and MIRAGE®
`
`VISTA masks respectively. Figures 11a to llf show prior art elbows in the WHISPER swivel I
`
`and swivel II masks manufactured by Respironics. Figures 12 and 13 show a prior art mask
`
`SERENITY mask manufactured by DeVilbiss in which the interior of the nasal cavity includes
`
`a baffle B for redirecting incoming gas.
`
`A mask that includes a cushion with a gusset will have a larger cavity, and hence more
`
`dead-space than a mask without a gusset, everything else being equal. Hence in a mask
`
`assembly with a gusset, particular attention needs to be paid to venting the mask to ensure that
`
`sufficient CO2 is washed out by a continuous influx of fresh air.
`
`Since the mask is to be used by sleeping users, it is also desirable to reduce or eliminate
`
`noise from all sources, including those caused by the venting of gases fiom the mask.
`
`Kwok (PCT/AU98/00067, published as WO 98/34665), the contents of which are
`
`hereby incorporated in their entirety by reference, describes a mask and a vent. In one form the
`
`vent comprises a soft flexible insert piece with a series of orifices.
`
`5
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`

`
`WO 2004/022147
`
`PCT/AU2003/001162
`
`4
`
`Drew et al. (PCT/AU00/00636 published as W0 00/78381), the contents of which are
`
`hereby incorporated in their entirety by reference, disclose a connector that comprises a mask
`
`end for connecting, in fluid communication, with the interior of a respiratory mask and a
`
`supply conduit end disposed at an angle to the mask end for connecting, in fluid
`
`communication, with the outlet of a breathable gas supply conduit. The connector also
`
`includes a gas washout vent passage having an inlet adjacent to, or forming part ofi the mask
`
`end in fluid communication with the interior of the respiratory mask and an outlet in fluid
`
`communication with the atmosphere. The outlet includes an interior surface that forms a
`
`smooth prolongation with an adjacent exterior surface of the connector. The vent outlet is
`
`disposed on the side of the connector remote the mask end, has a generally part-annular cross
`
`section and is adapted to direct the washout gas in a direction substantially perpendicular to the
`
`longitudinal axis of the mask end and substantially parallel to the longitudinal axis of the
`
`supply conduit end towards the supply conduit end.
`
`Moore et al. (co—pending provisional application serial no. 60/502,509, filed August 12,
`
`2002), the contents of which are hereby incorporated in their entirety by reference, describe a
`
`mask system including a swivel elbow with a vent.
`
`Correa er al. (U.S. Pat. No. 6,119,694) discloses a nasal mask assembly with a
`
`miniature nare seal. The mask assembly includes a conduit receptor that attaches to a gas
`
`delivery tube. Downstream of the conduit receptor is a bore that receives a stem having
`
`opposed flanges. The flanges separate the incoming gas into a plurality of channels, such that
`
`the gas is provided to one of a plurality of spatial regions in the interior of the nare seal.
`
`While the vents and connectors described in the previous references provide adequate
`
`intake ofbreathable air/gas and venting for masks that have a small amount of dead-space, e.g.,
`
`without gussets, they may be inadequate to provide air intake and CO2 removal in masks that
`
`have larger amounts of dead-space, e.g., with gussets. Therefore, there exists a need in the art
`
`for a swivel elbow and mask assembly that overcome the problems listed above.
`
`SUMMARY OF THE INVENTION
`
`A first aspect of the invention is directed towards providing an elbow for a mask which
`
`provides improved flow patterns for inlet and exhaust flows.
`
`6
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`

`
`wo 2004/022147
`
`PCT/AU2003/001162
`
`5
`
`A second aspect of the invention is directed towards providing an elbow, comprising a
`
`baffle.
`
`A third aspect of the invention is directed towards providing an elbow for a mask that
`
`includes an exhaust port for a mask and a baffle that extends from the elbow into the mask
`
`cavity.
`
`Another aspect of the invention is directed towards providing a swivel elbow including
`
`an exhaust port for a mask, wherein the swivel elbow includes structure for ensuring that fresh
`
`air from the blower does not directly reach the vent.
`
`Another aspect of the invention is directed towards a swivel elbow assembly that is easy
`
`to assemble and disassemble.
`
`Another aspect of the invention is directed towards a mask assembly using an elbow
`
`assembly that permits better intake of breathable air and/or better removal of exhaust air.
`
`Another aspect of the invention is directed towards a mask assembly using an elbow
`
`assembly that is quieter for the user and/or bed partner.
`
`Another aspect of the invention is directed towards an elbow assembly for a respiratory
`
`mask comprising an elbow, including a portion adapted to engage a gas delivery tube and
`
`another portion that is detachable and is coupled to the mask. The elbow fiirther defines an
`
`inlet port to deliver incoming gas into a nasal breathing cavity defined by the mask and an
`
`exhaust port separated from the inlet port by a curved baffle.
`
`Another aspect of the invention is directed towards providing an elbow for a mask
`
`comprising: (i) a portion for connecting to a gas delivery tube; (ii) a portion that is connected
`
`to a mask cavity; (iii) an inlet port to deliver incoming gas into the breathing cavity; (iv) an
`
`exhaust port to washout CO2; and (V) a baffle that separates the inlet and exhaust ports.
`
`Another aspect ofthe invention is directed towards a baffle for use with an elbow and
`
`mask assembly, for directing the inlet and outlet flows of the mask assembly.
`
`A further aspect of the invention is directed towards a mask assembly comprising a
`
`mask frame, a mask cushion, and an elbow assembly.
`
`7
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`

`
`WO 2004/022147
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`PCT/AU2003/001162
`
`6
`
`Other aspects, features and advantages of this invention will become apparent from the
`
`following detailed description when taken in conjunction with the accompanying drawings,
`
`which are a part ofthis disclosure and which illustrate, by way of example, principles of this
`
`invention.
`
`BRIEF DESCRIPTION OF FIGURES
`
`Figure 1 is an exploded cross-sectional view of a respiratory mask assembly according
`
`to one embodiment of the present invention;
`
`Figure 2 is an assembled cross-sectional View of the respiratory mask assembly shown
`
`in Figure 1;
`
`Figure 3a is a perspective View of a ring according to one embodiment of the present
`
`invention;
`
`Figure 3b is a cross-sectional view of a frame portion ofthe respiratory mask assembly
`
`shown in Figure 2;
`
`Figure 4a is a cross—sectional View of one embodiment of the swivel elbow according to
`
`the present invention;
`
`Figure 4b is a front View of the swivel elbow shown in Figure 4a;
`
`Figure 4c is a detailed cross-sectional view of the lower portion ofthe baffle shown in
`
`the swivel elbow of Figure 4b;
`
`Figure 4d is a perspective view of a swivel elbow according to another embodiment of
`
`the present invention;
`
`Figure 4e is a perspective View of a swivel elbow according to another embodiment of
`
`the present invention;
`
`Figure 5a is a front View of the respiratory mask assembly shown in Figure 2;
`
`Figure 5b is a left side view of the respiratory mask assembly shown in Figure 5a;
`
`Figure 5c is a right side View of the respiratory mask assembly shown in Figure 5a;
`
`8
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`
`wo 2004/022147
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`PCT/AU2003/001162
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`7
`
`Figure 5d is a top View of the respiratory mask assembly shown in Figure 5a;
`
`Figure 6a is a front View ofthe respiratory mask flame shown in Figure 5a;
`
`Figure 6b is a rear view of the respiratory mask frame shown in Figure 6a;
`
`Figure 6c is a front perspective view of the respiratory mask frame shown in Figure 6a;
`
`Figure 6d is a rear perspective View of the respiratory mask frame shown in Figure 6a;
`
`Figure 6e is a cross-sectional View along line 6e-6e of the respiratory mask flame
`
`shown in Figure 6a;
`
`Figure 6f is a right side view of the respiratory mask frame shown in Figure 6a;
`
`Figure 6g is a cross—sectional view along line 6g-6g of the respiratory mask frame
`
`shown in Figure 6b;
`
`Figure 6h is a cross-sectional view along line 6h-6h of the respiratory mask flame
`
`shown in Figure 6a;
`
`Figure 6i is a cross-sectional view along line 6i-6i of the respiratory mask flame shown
`
`in Figure 6b;
`
`Figure 6j is a cross-sectional View along line 6j-6j of the respiratory mask frame shown
`
`in Figure 6g;
`
`Figure 6k is a cross—seetional View along line 6k-6k of the respiratory mask frame
`
`shown in Figure 6a;
`
`Figure 61 is a bottom View ofthe respiratory mask frame shown in Figure 6b;
`
`Figure 6m is a detailed cross~sectional View of an exhaust port according to the
`
`embodiment of the respiratory mask flame shown in Figure 6g;
`
`Figure 7a is a front view ofthe front of the swivel elbow shown in Figure 4a;
`
`Figure 7b is an alternative flont View of the swivel elbow shown in Figure 7a;
`
`9
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`WO 2004/022147
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`PCT/AU2003/001162
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`8
`
`Figure 7c is a cross-sectional View along line 7c—7c of the swivel elbow shown in
`
`Figure 7a;
`
`Figure 7d is a right side View ofthe swivel elbow shown in Figure 7a;
`
`Figure 7e is atop View of the top of the swivel elbow shown in Figure 7a;
`
`Figure 7f a cross-sectional View along line 7f-7f of the swivel elbow shown in Figure
`
`Figure 7g is a rear perspective view of the swivel elbow shown in Figure 7a;
`
`Figure 7h is a front perspective View of the swivel elbow shown in Figure 7a;
`
`Figure 7i is a bottom view of the swivel elbow shown in Figure 7a;
`
`Figure 8a is a rear View of a prior art swivel elbow;
`
`Figure 8b is a rear View of a prior art swivel elbow;
`
`Figure 8c is a rear view of a related art swivel elbow;
`
`Figure 8d is a rear View of a related art swivel elbow;
`
`Figure 9a is a cross-sectional View of the front of the swivel elbow shown in Figure 8a;
`
`Figure 9b is a cross-sectional view ofthe front of the swivel elbow shown in Figure 8b;
`
`Figure 9c is a cross-sectional view of the front of the swivel elbow shown in Figure 8c;
`
`Figure 9d is a cross-sectional view ofthe front of the swivel elbow shown in Figure 8d;
`
`Figure 10a is a cross-sectional View of a prior art swivel elbow;
`
`Figure 10b is a cross—sectional view of a related art swivel elbow;
`
`Figure 10c is a cross-sectional View of a prior art swivel elbow;
`
`Figure 11a is a front view of a side of a part of a prior art swivel elbow;
`
`10
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`WO 2004/022147
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`Figure 11b is a left side View of the swivel elbow shown in Figure 11a;
`
`9
`
`Figure llc is a detailed cross-sectional View of vents on the swivel elbow shown in
`
`Figure 11a;
`
`Figure lld is an exploded view of a part of another prior art swivel elbow;
`
`Figure 1 1e is a cross—seetiona.l View of the swivel elbow shown in Figure 11d in an
`
`assembled state;
`
`Figure 11f is a bottom View of the swivel elbow shown in Figure lle;
`
`Figure 12 is a rear view of a prior art respiratory mask assembly;
`
`Figure 13 is a cross-sectional View along line 13-13 of the respiratory mask assembly
`
`shown in Figure 12;
`
`Figure 14 is a front perspective View of a swivel elbow according to another
`
`embodiment of the invention;
`
`Figure 15a is a front View of the swivel elbow shown in Figure 14;
`
`Figure 15b is a top view of the swivel elbow shown in Figure 15a;
`
`Figure 15c is a bottom View of the swivel elbow shown in Figure 15a;
`
`Figure 15d is a right side view ofthe swivel elbow shown in Figure 15a;
`
`Figure 15e is a right side view of the swivel elbow shown in Figure 15d;
`
`Figure 15f is a cross-sectional view along line 15f-1 Sf of the swivel elbow shown in
`
`Figure 156;
`
`Figure 15g is a cross-sectional View along line 15g—15g of the swivel elbow shown in
`
`Figure 15a;
`
`Figure 15h is a detailed view of a portion ofthe swivel elbow shown in Figure 15g;
`
`Figure l5i is a front perspective View of the swivel elbow shown in Figure 15a;
`
`11
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`10
`
`Figure 15j is a rear perspective View of the swivel elbow shown in Figure 15a;
`
`Figure 16a is a front perspective view of a swivel elbow according to another
`
`embodiment of the invention;
`
`Figure 16b is a rear perspective view of the swivel elbow shown in Figure 16a;
`
`Figure 17a is a front view of the swivel elbow shown in Figure 16a;
`
`Figure 17b is a top view of the swivel elbow shown in Figure 17a;
`
`Figure 17c is a bottom View of the swivel elbow shown in Figure 17a;
`
`Figure 17d is a right side view of the swivel elbow shown in Figure 17a;
`
`Figure l7e is a rear View of the swivel elbow shown in Figure 1721;
`
`Figure 17f is a cross-sectional view along line 17f-17f of the swivel elbow shown in
`
`Figure 17e;
`
`Figure 17g is a cross-sectional view along li11e 17g-17g of the swivel elbow shown in
`
`Figure 1721;
`
`Figure 17b is a detailed View of a portion of the swivel elbow shown in Figure 17g;
`
`Figure l7i is another fiont perspective View of the swivel elbow shown in Figure 1621 at
`
`a slightly different angle;
`
`Figure 17j is a rear perspective view ofthe swivel elbow shown in Figure 16b at a
`
`slightly different angle;
`
`Figure 18a is a front perspective View of a swivel elbow according to another
`
`embodiment of the invention;
`
`Figure 18b is a rear perspective View of the swivel elbow shown in Figure 18a;
`
`Figure 19a is a front view of the swivel elbow shown in Figure 18a;
`
`Figure 19b is atop View ofthe swivel elbow shown in Figure 19a;
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`11
`
`Figure 19c is a bottom View of the swivel elbow shown in Figure 19a;
`
`Figure 19d is a right side View of the swivel elbow shown in Figure 19a;
`
`Figure l9e is a rear view of the swivel elbow shown in Figure 19a;
`
`Figure 19f is a cross—sectional view along line 19f-19f ofthe swivel elbow shown in
`
`Figure 1%;
`
`Figure 19g is a cross-sectional View along line 19g-19g of the swivel elbow shown in
`
`Figure 19a;
`
`Figure 19h is a detailed view of a portion of the swivel elbow shown in Figure 19g;
`
`Figure l9i is another front perspective view ofthe swivel elbow shown in Figure 18a at
`
`a slightly different angle;
`
`Figure 19j is another rear perspective view of the swivel elbow shown in Figure 18b at
`
`a slightly different angle;
`
`Figure 20a is a front perspective View of a swivel elbow according to another
`
`embodiment of the invention;
`
`Figure 20b is a rear perspective view of the swivel elbow shown in Figure 20a;
`
`Figure 21a is a front view of the swivel elbow shown in Figure 20a;
`
`Figure 21b is a top View of the swivel elbow shown in Figure 21a;
`
`Figure 21c is a bottom view ofthe swivel elbow shown in Figure 21a;
`
`Figure 21d is a right side view ofthe swivel elbow shown in Figure 21a;
`
`Figure 21e is a rear view of the swivel elbow shown in Figure 21a;
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`Figure 21f is a cross—sectional view along line 21f-21f ofthe swivel elbow shown in
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`Figure 21e;
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`Figure 21 g is a cross-sectional View along line 2lg—2l g of the swivel elbow shown in
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`Figure 21a;
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`Figure 21h is a detailed View of a portion of the swivel elbow shown in Figure 2] g;
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`Figure 21i is another front perspective View of the swivel elbow shown in Figure 20a at
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`a slightly different angle;
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`Figure 21j is another rear perspective view of the swivel elbow shown in Figure 20b at
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`a slightly different angle;
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`Figure 22a is a front perspective View of a swivel elbow according to another
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`embodiment of the invention;
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`Figure 22b is a rear perspective View of the swivel elbow shown in Figure 22a;
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`Figure 23a is a front View of the swivel elbow shown in Figure 22a;
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`Figure 23b is a top View of the swivel elbow shown in Figure 23 a;
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`Figure 23c is a bottom View of the swivel elbow shown in Figure 233;
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`Figure 23d is a right side view ofthe swivel elbow shown in Figure 23a;
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`Figure 23e is a rear View of the swivel elbow shown in Figure 23a;
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`Figure 23f is a cross-sectional view along line 23 f-23f of the swivel elbow shown in
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`Figure 23e;
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`Figure 23g is a cross—sectional View along line 23g-23g of the swivel elbow shown in
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`Figure 23a;
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`Figure 23h is a detailed view of a portion of the swivel elbow shown in Figure 23g;
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`Figure 23i is another front perspective view ofthe swivel elbow shown in Figure 22a at
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`a slightly different angle;
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`Figure 23j is another rear perspective View of the swivel elbow shown in Figure 22b at
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`a slightly different angle;
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`Figure 24a is a front perspective View of a swivel elbow according to another
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`embodiment of the invention;
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`Figure 24b is a rear perspective View of the swivel elbow shown in Figure 24a;
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`Figure 25a is a front View of the swivel elbow shown in Figure 24a;
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`Figure 25b is a top view of the swivel elbow shown in Figure 25a;
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`Figure 250 is a bottom View of the swivel elbow shown in Figure 25a;
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`Figure 25d is a right side view of the swivel elbow shown in Figure 25a;
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`Figure 25e is a rear View of the swivel elbow shown in Figure 25a;
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`Figure 25f is a cross-sectional view along line 25f—25f of the swivel elbow shown in
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`Figure 25e;
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`Figure 25g is a cross-sectional view along line 25g—25g of the swivel elbow shown in
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`Figure 25a;
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`Figure 25h is a detailed View of a portion of the swivel elbow shown in Figure 25g;
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`Figure 25i is another front perspective view of the swivel elbow shown in Figure 24a at
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`a slightly different angle;
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`Figure 25j is another rear perspective view of the swivel elbow shown in Figure 24b at
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`a. slightly different angle;
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`Figure 26a is a front perspective view of a swivel elbow according to another
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`embodiment of the invention;
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`Figure 26b is a rear perspective View of the swivel elbow shown in Figure 26a;
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`Figure 27a is a front View of the swivel elbow shown in Figure 26a;
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`Figure 27b is a top View ofthe swivel elbow shown in Figure 27a;
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`Figure 270 is a bottom view of the swivel elbow shown in Figure 27a;
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`Figure 27d is a right side View of the swivel elbow shown in Figure 2721;
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`Figure 27e is a rear View of the swivel elbow shown in Figure 2721;
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`Figure 27f is a cross-sectional view along line 27f-27f of the swivel elbow shown in
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`Figure 27e;
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`Figure 27g is a cross-sectional View along line 27g-27g of the swivel elbow shown in
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`Figure 27a;
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`Figure 27h is a detailed View ofa portion ofthe swivel elbow shown in Figure 27g;
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`Figure 27i is another front perspective view ofthe swivel elbow shown in Figure 26a at
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`a slightly different angle;
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`Figure 27j is another rear perspective View of the swivel elbow shown in Figure 26b at
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`a slightly different angle;
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`Figure 28a is a front perspective view of a swivel elbow according to another
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`embodiment of the invention;
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`Figure 28b is a rear perspective View of the swivel elbow shown in Figure 28a;
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`Figure 29a is a front View of the swivel elbow shown in Figure 28a;
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`Figure 29b is a top view of the swivel elbow shown in Figure 29a;
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`Figure 29c is a bottom View ofthe swivel elbow shown in Figure 29a;
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`Figure 29d is a right side View ofthe swivel elbow shown in Figure 29a;
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`Figure 2% is a rear View of the swivel elbow shown in Figure 29a;
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`Figure 29f is a cross-sectional View along line 29f-29f of the swivel elbow shown in
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`Figure 2%;
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`Figure 29g is a cross-sectional view along line 29g-29g of the swivel elbow shown in
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`Figure 29a;
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`Figure 29h is a detailed view of a portion of the swivel elbow shown in Figure 29g;
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`Figure 29i is another front perspective view of the swivel elbow shown in Figure 28a at
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`a slightly different angle;
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`Figure 29j is another rear perspective View of the swivel elbow shown in Figure 28b at
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`a slightly different angle;
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`Figure 30a is a side view of a swivel elbow according to another embodiment of the
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`invention;
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`Figure 30b is a right side View of the swivel elbow shown in Figure 30a;
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`Figure 30c is a top view of the swivel elbow shown in Figure 30a; and
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`Figure 30d is a partial bottom View ofthe swivel elbow shown in Figure 30a.
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`DETAILED DESCRIPTION OF ILLUSTRATED EMBODIMENTS
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`Figure 1 shows an exploded cross-sectional view of a mask assembly 5 according to
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`one embodiment of the present invention. The mask assembly 5 is intended to be worn by a
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`user 1 and substantially surrounds the nose 3 of the user 1. The mask assembly 5 includes, for
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`example, a mask frame 10, a swivel elbow assembly 20 connected to the mask flame 10, and a
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`cushion 30 connected to the mask frame 10. The swivel elbow assembly is adapted to be
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`connected to an air tube 168 that delivers breathable gas to the user 1.
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`The cushion 30 is designed to substantially surround the user’s nose 3 and apply
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`pressure around the cushion’s 30 perimeter while minimizing and/or avoiding contact with
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`pressure sensitive regions on the user’s face. Some parts ofthe user’s face, for example, the
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`nasal bridge region, require special attention to achieve a balance between pressure and seal. It
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`is also desirable to provide a low profile mask to improve the comfort level of the user 1 by
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`improving stability, and to reduce the forces which may tend to pivot the mask assembly 5
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`relative to the user’s face. While the cushion 30 is shown as being used with a nasal mask
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`assembly, it can also be designed for use with a full face mask or a nasal/oro mask assembly.
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`The cushion 30 has a face—contacting side 38 and a non face-contacting side 39. The
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`non-face contacting side 39 of the cushion 30 engages the mask frame 10 at points 34a and
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`34b. Any type of connection system can be used for connecting the cushion 30 to the mask
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`flame 10 in the mask assembly 5. Some examples include interior cushion clips or exterior
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`cushion clips, which are used in ResMed’s Ultra Mirage® mask, which is described in U.S.
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`Patent No. 6,412,487, incorporated in its entirety herein by reference. The cushion 30 can be
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`permanently or detachably and/or reattachably connected to the mask frame 10. Other forms of
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`cushion connection may be used such as fiiction fits, gluing and tongue and groove
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`mechanisms.
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`The mask frame 10 includes at least one aperture 42, adapted to fit the elbow assembly
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`20. The aperture 42 has a diameter in its broadest aspect between about 20 mm to about 40
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`mm, more preferably a diameter between about 25 mm to about 30 mm, and most preferably a
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`diameter of about 28 mm. The aperture 42 preferably has a generally circular shape. However,
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`the aperture 42 may have a non-circular shape. Further, the mask frame 10 may have a
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`plurality of apertures therethrough with the elbow assembly 20 coupled to the mask frame 10
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`such that it surrounds the plurality of apertures.
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`Figure 2 is a cross-sectional View of the mask assembly 5, showing one embodiment of
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`the mask frame 10, one embodiment of the cushion 30, and one embodiment of the elbow
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`assembly 20, connected together according to one embodiment of the present invention. Figure
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`2 also shows a vent cover 180 attached to the swivel elbow 160. The vent cover 180 directs
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`exhaust air along the air tube therefore avoiding disturbance of a bed partner and minimizing
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`noise.
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`The aperture 42 may optionally include a ring 400. Figure 3a is a perspective View of
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`the ring 400. Ring 400 includes an outer ring 310 and an inner ring 307 defining a passage 306
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`which directs exhaust through the vent cover 180, e.g., via a vent cavity 308. The outer ring
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`310 is attached to the inner ring 307 by at least one connecting arm 304. In the embodiment
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`show in Figure 3a, ring 400 has three connecting arms 304. It would be evident to a person
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`skilled in the art that different numbers of connecting arms 304 can be used.
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`In one embodiment, the ring 400 is fabricated as one piece with the mask frame 10. In
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`this embodiment, t