AU2010241390A1

AU2010241390A1 - Patient Interface and Aspects thereof

Info

Publication number: AU2010241390A1
Application number: AU2010241390A
Authority: AU
Inventors: Olivia Marie Allan; Arvin San Jose Gardiola; Lewis George Gradon; Wen Dong Huang; Alastair Edwin Mcauley; Mark Mclaren; Craig Robert Prentice; Andrew Paul Maxwell Salmon; Silas Sao Jin Siew
Original assignee: Fisher and Paykel Healthcare Ltd
Current assignee: Fisher and Paykel Healthcare Ltd
Priority date: 2008-05-12
Filing date: 2010-11-12
Publication date: 2010-12-02
Also published as: AU2016238904B2; AU2019208240B2; AU2019208240A1; AU2021245217A1; AU2016238904A1

Description

Regulation 3.2 AUSTRALIA PATENTS ACT, 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT ORIGINAL Name of Applicant- FISHER & PAYKEL IEALTHCARE LIMITED Actual Inventors: AT I AN, lbvia Marie: GJARDIOLA, Arvin San Jose; GRADON, Lewis George; HUANG Wen Dong; McAULEY, Alastair Edwin, McLAIGEN, Mark; PRENTICE, Craig Robert; SALMON, Andrew Paul Maxwell; STRW, Silas Sao Jinf Addrsss for serve in A J PARK, Level 21, 60 Marcus Clarke Street, Canberra ACT Austrnala: 2601 Australia Invention Tide: Patient Interface and Aspects Thereof The following statrent is a uIll deseriplion of this inrvennon, inducding the best mtthod of performing it known to us.

-2~ FIELD OF THE INVENTION The inventions described herein relate to interfaces for providing a supply of pressurised gas to a recipient %ia the naasal passages. The inveniron' nay be included in appliances that also 5 supply gas to the oral passages, for example by incorporation into a broader full face mask. SUMMARY OF THE PRIOR ART The prior art includes a wide variety of interfaces fox supplying gases to a recipient. The following are examples. The prior art includes a nasal mask that can be used for supplying gases to a recipient. The 10 nasal mask includes a perimeter seal that seals across, down each cheek alongside the nose- and along the surface of rhe Upper lip. The entire enclosed space is ptessuised and the recipient may inhale the pressucised gas fom the enclosed space. Ar example is the Fiexifit 405 nasal mask sold by Fisher & Pavkel Healdicare. The prior art includes a full face mask, The full face mask includes a perimeter seal that 15 extends across the bridge of die nose downward along each cheek beside the nose to the jaw and along tne jaw below the lower lip. The perimeter thereby encloses both the nose and mouth the entire space within the mask frame is pressurised The recipient may breathe the pressurised gas fromn the space through either the nose or mouth. An example is the Flexifit 431 interface sold by Fisher & Pavkel Healthcare. 20 The prior att includes an oral interface including an oral appliance that Ets within the user's mouth. An example is die Fisher & Pavkel Healthcare Oracle interface. The prior art includes a nasal ole'ows incerface in which headgear retains a soft plenum in the vicinity of the user's nose. A pair of flexible protrusions engage against the nares of the recipient. Typically, die prutrusions are able to axially compress and have a lateral freedom of 25 movement relative to the supporting cushion. An example is the ResMed Swift nasal pillows 'The prior an includes a rasal cannula interface. The nasal canal interface includes a plenum portion Lhat rests against the upper lip of the user and a pair of prongs. Each prong extends into the nostil of the user. Arn example is the Nasal Aire interface made by Innomed. 30 interfaces such as these are frequently used for delivering pressurised gases to a person being treated foE obstructive sleep apnea (OSA) or other sleep disorders. These users typical wear the interface in a home sleeping environment. Comfort and effective sealing even under conditions of patient movement are maJor considerations. The term "comprising" as used in this specification means "consisting at least in part of', 35 When interpreting each statement in this specification that includes the termn "comprising") features -3 other than that or those prefaced by the term may also be present. Related terms such as rise and "comprises" ar to be interpreted in the same manner SUMMARY OF THE INVENTION An object of the present invention is to provide an interface which will at least provide the 5 industry and users with useful choice. In a first aspect the invention consists in a patient interface comprising a supple envelope, bag or balloon, with an air supply aperture and a pair of protruding nostril locators p.rotruding from the envelope, each nasal locator including an outlet aperture, the envelope, bag or balloon inflating under internal pressure from a pressurised gases supply and when pressed against the face 10 of a user, creating a seal with the nose or face of the user in addition to any seal provided by the nasal locators. According to a further aspect the envelope has at least two integral connectors to attach a head strap m the envelope. According to a further aspect the imnerface includes a frame having a gases inlet for 15 conneeCon wsih a gases supply conduit and a gases outlet including a protcuding lip, where the gases supply aperture of the envelope is engaged or engag-able over the protruding lip of the frane. According to a futther aspect the frue has at least two integral connectors to attach a head strap to the frame. According to a funhett aspect the frane includes a strap to srabilise the envelope, the srmp 20 extending above the frame. According to f further aspec- rhe strap is integrally formed with the frame According to a fa:hier aspee: the strap . separate to the frame yet fastened to said frame. According to a further aspec: the envelope includes an elongate strip integrally fonned in the envelope to stabilise the envelope, the strip extending in an arc above the frame. 25 According to a further aspect the envelope, when inflated without stretch, will not pass through a circular aperture of 40nmm diameter without contact. According to a either aspect the envelope collapses when not inflated= According to a further aspect the envelope or the body of the envelope, in use, forms a substantially continuous seal against the user's nose and face that surrounds the nostril loeators 30 According to a further aspect the envelope wraps completely about the user's nose. According to a further aspect the envelope has side portions that extend completely about the sides of the user's nose and at least partially over the user's cheeks. According to a further aspect the envelope has a cut out in the nasal bridge region of the UScr.

-4 According to a father aspect wherein, rin use, the side wAl of the envelope rolls to accomodate Inovenent of the mask frame relative to die nose, where rolls means that the portion of the envelope adjacent to the fatmte reduces at one side and extends at the other, and the corresponding pornons adjacent the face extend at one side and reduce at the other, According to a further aspect the civelope allows fur this rnovement in any direction relative to the nose. According to a further aspect the envelope allows for a toll of at least 10man without exposing the nostril locators. According to a further aspect substantially the entire envelope, except for a region 10 immediately adjacent and including the nostril locators and innediarely adacen and. in holding the inlet opening, is cupple, and the region immediately adjacent and including the area immediately adjacent the inlet opening has any suitable stiffness. Accordng to a furthet aspect the region imediarely adjacent the inlet opening is stiffer than the rest of the envelope. 15 Accordng to a further aspect the region imnediarely adjacent the nosti locators is stiffer than the lest of the envelope. According to a further aspect a connector is engaged with or formed in the interface frame, According to a further aspect the interface includes a short Iengtb of supple breathing conduit that is connectable to the frame. 20 According to a further aspect the interface includes a including a short length of breathable conduit that is connectable to the frame. Accordimg to a further aspect the interface includes a lanyard or tether connected to a length of breathuing conduit connected to he Frame. According to a further aspect the lanyard or tether is connected to the conduit at a location 25 between 10cm and 50cm from the frame. According to a further aspect the interface includes a frame supporting the envelope, the frame including at least one soft or flexible portion at :he perimeter. According to a futhet aspect the frame includes at least a pair of extended support members at he plerier, the support members located either side of the frame such that they 30 may. but do not necessarily, contact portions of the face of the user in usC According to a further aspect the interface includes at least one strap extending from one side portion of the frarne to the oiier side portion of the frame, tne strap being sufficient to pass around the back of the head of the user According to a farther aspect the strap is adjustable in lengthy.

- 5 According to a further aspect each end of the strap is bifurcated and the two lanbs of the bifiu-cated end connect to the side portion of the frame at spaced apart locations. According to a further aspect the interface includes a bias flow outlet in one or more of the envelope, a frame or connector. 5 Accordng to a further aspect the envelope is inflated and holds its shape against the force of gravity with an elevated intemal pressure equivalent to 3cm -HO. in a further aspect the invention consists in an inrerface that includes an inflatable envelope (that could also be refered to as a bag or balloon) having a supple wall strucmte.- The inflatable envelope has a pair of locating protmsslons rhar engage in the nostrils of the user. The locating 10 protrusions supply gases flow to the Lset ftn inside the envelope. The envelope is so supple, anf(d of sufficient dimension and shape, that when the infHated envelope is pressed against the face of a user, with the locating protrusions engaged in the nostrils of the user, the envelope contacts the surfaces of the users face (the nose, the upper Up and the cheeks) and provides a seal. In one aspect, dhe present invention may broadly be said to consist in a patient interface 15 comprising: a single loop headstrap, a mask for covering at least the nostrils of the user, the single Loop headstrap extending from the mask at either end, a swivel or ball join at the mask to couple a supply conduit to the mask in use to allow rotation of the supply conduit through different angles and orientations relative to the mask. According to a fintier aspect, LhC mask includes an inflatable seal with an air supply 20 aperture and a pair of protrudig nostril locators protruding from the seal, each nasal locator ircIuding an ouet c aperture According to a further aspect, the seal inflates under iternal essure fom a pressuinsed gases sUpply and when pressed o"gaist the tace of a use, creating a seal with the nose or face of the user in addition to any seal provided by the nasal locatorsL 25 According to a father aspect, the interface includes a frame having a gases inlet for connection with a gases supply conduit, and a gases outlet including a protruding lip, and the gases supply aperture of the seal is engaged or engagable over the protruding lip of the fratne. According to a further aspect, the seal, in use, forms a substantially continuous seal against the user's nose and face that surrounds the nostil locators. 30 According to a further aspect, excepi. for a region inmedia tely adjacent and including the nosral locators and imrdiacely adjacent and including the air supply. aperture, the seal is supple, and rhe region immediately adjacent and including, the inlet opening and has any suitable stiffness. According to a further aspect, the patient int erface includes at least a pair of extended support members at the perimeter of the mask, the support members l ocated either side of the 35 mnask such that they may, but do not necessarily, contact portions of the face of the user in use.

- 6 According to a further aspect, the strap extends from one side portion of the frame to the other side portion of the frmne, the strap being sufficient to pass around fhe back of the head of the user. According to a further aspect, the patient interface includes a short length of supple 5 conduit connected to the swivel or ball joint. A according to a further aspect, the patient interface includes a te-rally eAtcnded support that e press on a lower facial pordon of the user outside he periphery of the seal According to a further aspect, the laterally extended support can press on the lower check portion of thc user ICL According to a further aspect, the latemrlly extended support may only occasionally contact the face of the user in usc. Ia a further aspect, the present inventLon may broadly be sad to consist in a patient interface including a mask including seal neans for scalin'g with the face of a user and fA-rae ieanos fto r supp e sea and manS for secu.ting he mask to the head of a user. 15 According to a further aspect, the patient interface includes a conduit for deliverig gases to the mask, and means for supporting the weight of the conduit from substantial affecting the mask in use. In a further aspect, die present invention may broadly be said to consist in a patient interface comprising: a mask for covering at least the nostrils of die user, nd including a seal body 20 and a frame connected with the seal and a laterally extended support that can press on a lower facil portion of the use: outside the periphery of the seatI Accor-dinig to a further aspect, the mask includes an infhatable sea! with an air supply aperture and a pair of protruding nostril locators protruding fom the sea, each nrsal locator including an outlet aperture. 25 Accor-ding to a further aspect, the seal inflates under icrnal pressure from a pressurised gases supply and when pressed against die face of a user, creating a scal with the nose or face of the user in addition to any sceal provided by thc nasal locators. According to a further aspect, in use, the side wall of the envelope rolls to accommodate tmoverent of the mask frame relative to the nose, wherein rolls means that the portion of the 30 envelope adjacent to the frame reduces at one side and extends at the other, and the corresponcding portions adjacent the face extend at one side and reduce at the other. According to a further aspect, the frame includes at least a pair of extended support members at the perimeter, the support members located either aide of the frame such that they may, but do not necessarily, contact portions of the face of the use in use.

-7.

According to a further aspect, the. patient interface inchwles a single loop strap exterdng from one side portion of the frume to the other side portion of the frame, the strap being sufficient to pass around the back of the head of the user. According to a further aspect, the laterally extended support can press on lie loweCr chuck 5 portion of the user. According to a further aspect, the laterally extended support roay only occasionally contact the face of the LISC In ue. inl one aspect, the present invention may broadly be said to consist in a patient interface comprising: a nasal seal including a face contacting side, the nasal seal being formed ofa soft 10 flexible material, and including a central portion to extend across the base of the nose, and a side portion exending from each end of the cenmra porrton, each side portion extending across the a side of the nose, a face contacting side of the scal being supple to conform under internal pressure to the surfaces of the nose of a wearer, incbal g, at the side portons of the seal, to outside surfaces of the sides of tile nose, an exterior side including regions murch stiffer than die supple 15 interior side, the regions extending into the side portions of the seal. According to a further aspect, wherein the side portions of the seal arc substantially parallel to each other and substantially normal to the central portion of the seal According to a fuither aspect, the outer walls of the side portions of the seal are alined to have an angle between their orientations between 0 degrees and 30 degrees. 20 According to a further aspect, the seal includes a pair of nasal locators on the face contacting side, and the seal is stiffer in the region immediately adjacent and including the nasal locators than in a region surrounding this region, en tc face countactig side of the scaLi According to a further aspect, a penpheri portion of the seal, joining the face contacting side to the exterior side is supple ard allows the interior side of the scal to displace relative to the 25 exterior side. According to a further aspect, the exterior side of the central portion of the seal mcludes an aperture for passing gases to and from. the interior of th.e scat According to a ftuther aspect, the supple portions of the seal comprise a silicone material with a thickness between 0.05mrn and 0.5mrm 30 According to a further aspect, the le portions of the seal comprise an elastomer with a thickness between 0.1nm and 0.2nm. According to a father aspect, the stiff portions of die seal comprise a silicone material wita a thickness between 2mm and 3mm. According to a further aspect, the supple portions of the seaL comprise an elastomer with a 35 thickness between 2tmma and 3mn.

-U

According to a further aspect, the region immediately adjacent and including the nasal doctors compnses a silicone matenal with a thickness between 0.5mm and. 2-m, According to a further aspect, the seal has an overall width From outside surface of one side portion to outside surface of the otber side poron of between 30mm and 60mm.. According to a further aspect, the seal has an overall depth, from the outer surface of the central portion to a line joining the extreme ends of each side portion, between 40mm and 65mm. According to a further aspect, the patient interface includes a body assembled to the nasal seal, the body being formed of a material more rigid than the nasal seal, and together with die nasal seal forming an. enclose having an inlet opening and a patient oudet opening, with a swiveling 10 elbow connected to the inlet opening. A according to a fthrther aspect, the coonection of the swivel elbow to the body provides for rota Lion of the swivel elbow relative to the body and pivoring of the swivel elbow relative to the body about at least a transverse axis. According to a farther aspect, the connection comprises a ball joint 15 According to a further aspect, the elbow includes a first end and a second end and a flow path between the first end and the second end, the flow path aligned m the first direction at the first end and the second direction a- the second end, and the first direction and the second direction including an angle of between 120' and 1 K, According to a further aspect, the angle is between 120" -Ind 150 '. 20 According to a further aspect, the angle is between 13120 and 1400. According to a further aspect, the elbow includes a gas washout vent. According to a ifirther aspect, tie gas washout vent is aligned with a gas flow pad in:o the elbow from the nasal seal and body assembly. According to a further aspect, the gas washout vet comprises a pluraity of holes through a 25 wall of the elbow Accordmg to a further aspect, the patient interface includes a body assembled to the seal, and a strap extending from the assembled body and nasal seal in a loop, the strap depardng a first portion of the assembled body ad nasal seal at one cnd and a second pordon of the assembled body and nasal seal at its other end. 30 According to a further aspect, the strap comprises a single undivided band along the length of the strap that engages the head of the wearer. According to a further aspect, the strap engages the body at either end. According to a further aspect, the body is Formed from a rigid material, the strap is relatively flexible compared to the body and includes a soft portion, a portion of the strap that 35 engages the body formed of a material more flexible than die material of the boy and less flexible than the rnaterial of the strap such that, when engaged to the body, the soft portion forms a soft extension of the body, According to a further aspect, the soft portion extends 5ru to 60mm along the strap, According to a further aspect, the strap engages the body with a releasable connector at 5 either end. According to a futhe aspect, the strap includes a soft cover portion extending from the releasable connector for a distance of 5mr to 60mm along the strap, the soft covet por tion being formed of a material softer than thec bodv. According to a further aspect, the band is narrow, preferably less than 10mm wide. 10 According to a further aspect, the band is less rhan 6mrn wide. Accordig to a further aspect, the band has a stiffness less than 2N per 1n00mm cxrcnsion trom a relaxed condition. According to a further aspect, the band is formed fon a knitted or braided yarm incorporating filaments of a material with high elasticity and filaments of material of much higher 15 stiffness. According to a further aspect, the strap includes soft end portions that are more rigid than the strap between the end portions, but softer than the body, the soft end portions also acting as soft Cxtension portions of the body. According to a further aspect, the patient interface includes a tube depending from the seal 20 and body, and a tube support, connected to the tube and connecutblc to he neck or clofling of a patient. According to a further aspect, the tube support includes a collar fasmnable about the neck of a wearer. According to a further aspect, the. collir has a first end portion and a second end portin, 25 the first end portion and the second end portion include a fastening arrangement allowing le end portions to be fastened with a selected amount ofoverlap. According to a further aspect, the collar includes a third end portion and a fourth end portion anI a connector connecting the third enud poison to the fourth end portion. According to a further aspect, the connector is conigured to release the third end portion 30 from the fourth end portion upon application of tension across the connector greater than a release pension, wherein the release tension is less than ION. According to a further aspect, the collar is between 30mm and 60mm wide. According to a further aspect, the collar has a core :nateru and a cover material surrounding the core material 35 According to a further aspteci:, the core material is a dimensioxiaJy stable, batheiable mesh.

-10 Accordig to a further aspect, the cover material is a braided or tutted natural fibn. According to a further aspect, the tube support includes a tether extending from the colar, with a connector a: one end secuteid or securale to the tube. According to a further aspect, tether includes a connector at the outer end, with the collar 5 passing through the second connector. According to a further aspect, the tether includes a first end and a second end and a connector connecting the List end and the second end, the connector being configured to release upon application of a tension above a release tension, wherein the release tension is less than lON According to a further aspect, the connector of the srrap includes a first portion and a 10 second portion, and in the engaged condition, fe first poron can swivel rearive t t he second portion. According to a further aspect, the connector to engage with the tube comprises a ring. Accordmg to a fluffier aspect, the patient interface includes a body connected to the seal, and wherein the body includes a nasal seal engaging portion that engages an outward side of the 15 seal, an inlet opening and at least one strap engaging pordon from which extends a loop strap to secure the interface to the patient According to a further aspect, the patient interface includes a soft intermediate portion where the loop strap extends from the strap engagmg portiout, the soft intermediate portion being more rigid than the strap but formed of material softer than the material of the body 20 According to a further aspect, the body includes two strap engaging portions, each strap engaging portion extending laterally away from the inlet opening, from opposite sides of the inlt opening. According to a further aspect, each strap engaging portion extends away fironn the inlet opening in a region where the strap engaging portion overaps wit the outer wail of the seal 25 According to a further aspect, a central portion of the body defines a convex shape generally matching a convex shape of the outer wall of the body, with strap engaging portions extending from lateral extremes of the central portion, the srrapt engaging pomons exrentding away from the central portion at an angle outwardly aligned relatve to he general convex shape. According to a fuzLher aspect, the strap engaging prtions extend away from the outer wall 30 of the seal with an included angle between then greater than degrees. According to a further aspect, the strap engaging portion from the point where it diverges from the outer wall of the seal is between 50% and 150% o f the length of the equivalent length of the outer wail of the seal According to a further aspect, the patient interface includes a body engaged with the nasal sea], the bAdy being more rigid than the nasal seal, wherein a lip support depends from thec body, and extends beyond an edge of the seal According to a further aspect, the lip support includes one or nmo:e pads for engaging 5 against an upper lip portion of the wearer. According to a funher aspect, the lip support inchides two depending legs, spaced apart at either lateral region of the seal, each leg extending beyond a lateral portion of the lower edge of the seat According to a further aspect, each leg carries a pad portion oriented to present a face 10 against the upper lip A according to a tnuther aspect, the legs are moulded to have lower stiffness about an axis parallel to the lip ponion of the wearer which they will contact, than about an axis normal to the plane of the lips, In a further aspect., the present invention may broadly be said to consist in headgear for a 15 patient interface, the headgear comprising: resilient band ha-ving a width between 3mm and 6mm, a stiffness providing an extension of 150ni with a force less than 2N, a first end connected or connectable to a first lateral portion of a mask, and a second end connected or connectable to a second lateral portion of a mask. According to a further aspect, the bands betwrn 350mrn and 450mm long in its relaxed 20 lengdh, According Lo a further as pect, Ilhe band is between 60mm and 0mm longer upon application of an extension force of IN. According to a further aspect, the band is constructed from a knifed or braided yarn, where the yarn includes filaments of a first material and filaments of a second material of tigh 25 elasticity bt much lower stiffness than the first material. According to a further aspect, the band comprises a braided yarn, and the yarn comprises an elastane filamnt with a spun wrapper. According to a further aspect, the band comprises a plurality of braided thread bandes, and eaci thread bundle corn-ises at least two threads, and each thread comprises an elastane core and 30 spun wrapper According to a farther aspect, the first swap end, the second strap end or both include a soft cover portion, extending 5mrn to 60mr along the strap, the soft cover portion being more rigid than the strap. According to a ftuther aspect, the cover portion is of a softer nateril than dte Lateral 35 portion of the mask to which it is intended to connect According to a fu-rther aspect, the headgear includes a first connector at the ntst end and a second connector at the second end. According to a further aspect, the connector includes a resiliently deformable spring clip engaged in a clip body. 5 According to a further aspect, the connector includes a cover surrounding and at least substantially encapsulating the clip body md a portion of the band, the cover being more rigid than the band and being formed of a material softer than the material of the clip body. According to a further aspect, the invention may consist im a patient interface mluchding a strap a ecnrding to any one o more of the above paragtaphs. 10 In a further aspect, the present invention may broadly be said to consist in a patient interface comprising: a nasal sea including a face contacting side, the nasal seal being formed of a soft flexible rvterial a body assembled to the nasal seal the body being formed cf a material more rigid than the nasal seal, and together with the nasal seal forming an enclosure having an inlet opening and a patient: outlet opening, and a lip support depends from the body, and extends :5 beyond an edge of the seal. According to a fi irther aspect, the lip support inchdes one or mor pads for engaging against an upper lip portion of the wearer. According to a further aspect, the lip support inch des two depending legs, spaced apart at either lateral region of the sea, each leg extending beyond a lateral portion of the lower edge of the 20 scaL According to a further aspect, each leg carries a pad portion oriented to present a face against the upper lip. According to a further aspect, the legs are moulded to have. lower stiffness about an axis parallel to the lip portion of the wearer which they will contact, than about an axis normal to the 25 plane of the lips. According to a further aspect, the patient interface includes a gases supply tube depending from the body and a strap extending from the assembled frame and nasal seal in a loop, the strap departing a flrst portion of die assembled body and nasal seal at one end arnd second portion of the assembled body and nasal scal at irs other end. M IT a further aspect, the present invention may broadly he said to consist in a patient interface composing: a mask, a tube depending from tile mask, and a tube support, connected to the tube and including a collar fastenable about the neck of t wearer. According to a further aspect, the collar has a first end portion and a second end portion, the fast end porion and the second end portion including a fastening arrangement allowing the 35 end portions to be fastened with a selected amount of overlap.

According to a further aspect, the collar includes a dtird end portion and a fourth end portion -and a cormector connecting the third end portion to the fourth end portion. According to a further aspect, the connector is con6gured to release the third end portion from the fourth end portion upon application of tension across the connector greater than a release 5 tension, wherein the release tension is less than 10N. According to a further aspect, the colar is betw cen 30mnr and 60mn wide. According to a further aspect, the collar has a core maternal and a cover material surrounding the core materiaL According to a further aspect, the cole tmateial is a dimensionally stable, breathable mesh., 10 According to a father aspecE, the cover material is a raided or knitted natural fibre According to a further aspect, the tube support includes a tether extending from the collar. with a connector at one erd secured or securable to tie tub-. According to a fudher aspect, the tether includes a connector at the outer end, with the collar passing through the second connector, 15 According to a further aspect, die tether includes a first end and a second end and a connector connecting the first end and the second end, the connector being configured to release upon application of a tension above a release tension , wherein the release tension is less than ION. According to a further aspect, the connector of the either includes a first portion and a second poaron, and in the engaged condition, the first portion can swivel relative to the second 20 portion. In a further aspect, tlhe present invention roay broadly be said to consist in a patient interface comprising: a nasal seal including a face contacting side, the nasal seal being formed of a soft flexible material, and including a central portion to extend across the base of the nose, and a side portion extending from each end of the central portion, each side portion cxtendion ncross the 25 a side of the nose, a body connected to the seal, including a nasal seal engaging portion that engages ar outward side of the seal, an inlet opening and at least two strap engaging portions, each strap elgagng poruon Cxtending laterally away from the inlet opening, from opposite sides of the inlet opening, and a strap extending between the strap engaging portions; and wherein a central portion of the body defines a convex shape generally matching a convex shape of the outer wall of 30 the body, with strap engaging portions extending from lateral extremes of te central portion, the strap engaging portions extending away f-rm the central portion at an angle outwardly aligned relative to the general convex shape. According to a further aspect, the strap engagmig portions extend away from the outer wall of the scal with an included angle between them greater than 30 degrees.

- 14 According to a further aspect, the strap engaging portion from the point where it diverges from the outer wall of the seal is between 50% and 1 50% of the length of the equivalent length of the outer wall of the seal. According to a further aspect, the patient interface includes a soft intermediate portion 5 where the loop strap extends from die strap engaging porcon, the soft intennediale portion being more rigd than the strap but formed of material softer than the matrial nof the body. In a further aspect, the present invention may broadly be said to consist in a patient :nterface comprising: a single loop hcadstrap, a mask for coveting at least the nostils of the user, the single loop hcadstrap extending from the mask at either end, a supply conduit less than 200nmm 10 long, coupled to the mask for free swiveling movement including substantial rotation about ruliple orthogonal axes. According to a further aspect, the supply tube is flexible to an extent that the tube passes the test described he1ein with reference to Figure 64. In a further aspect, the present invention may broadly be said to consist in a patient 15 interface comprising: a mask for covering at least the nostls of the user, a supply port on the mask for receiving a supply of gases, a bias flow vent on the mask extending from an inside of the rsqk to an outside of the mask, the bias flow vent directing flow in a direction less than 45" to the coronal plane of the head of a hypothetical wearer, and in a direction generally toward the forehead. 20 Accordimg to a further aspect, the bias flow vent comprises at least one bia flow aperture in a wall of the mask, the portion of the wall having the bias flow aperture being aligned more than 454 to the coronal plane of die weaner. According to a further aspect, the portion of the wall having the bias low holes is located within a front wall of the mask, and the portion forms a shelf relative to a surrounding portion of 25 the front wall. According to a farther aspect, a plurality of bias flow holes are distributed in a cinve :ArouLlnd the upper front portion of the interface. According to a further aspect, the mask has a general U-shape or V shape to wrap around the nose of the user arid the bias flow vent is located at the base of the U (rV. 30 According to a further aspect, the seal does not cover die nasal bridge of the wearer. In a further aspect, the present invention may broadly be said to conist in a patient interfatc comprising: a frame and a seal, the seal including a patient-facing side with at least one patient opening and a frame-facing side with at least one frame-facing opening, the seal engaging with the frame at a lip defined by the perimeter of the frame-facing opening, the frame including a 35 first component part and a second component par, the first components part including a first -15 portion of a channel for engaging the lip of the seal, the second component pan including a second portion of the chanel for engaging the lip of the seal, the seal being engageable and disengageable from the channel with the first and second component parts connected to form the channel. In a further aspect, the present invention may broadly be said to consist in a patient 5 interface comprising: a frame and a scal, the frame including a first component part and a second component part engaged together. the fast component part including a portion forcing a socket with surfaces For contacting movirig parts of a Freely swivelling connector, tme second part comnpnmng a outer cover, with an opening at the location of the socket of the ist part, and the patient interface further including a connector with a joining part projecting past the cover into the 10 socket Of the first part to be engaged in the socket of the first part for free swivelling movement. According to a further aspect, the first component is forced from q different material to the cover, and die cover and dhe connector are orned from the sane material. According to a further aspect, the patient inter-face includes a seal includig a pair of nasal locators extending from a supple background, each nasal locator including a tip, the nasal locator 15 becoming narrower moving from the background to the tip, and an opening in the tip of the nasal locator, the opening, and te cross-sectional profile of the tip portion of the nasal locator, being oval or elliptical and having a ratio of the length of the major axis to the length of the mior axis greater than 15. According to a Lather aspect, the ratio of the length of the major axis to the length of the 20 minor axis is between 1.5 and 3, According to a farther aspect, the tip portion of the nasal locator includes a lip adjacent the rip opening, the lip being thickened relive to adjacent po-dons of the tubular portion. According to a further aspect, the nasal locator includes a dome portion adjacent the background and a tubular portion extending from an apex of the dome portion. 25 According to a further aspect, the tubular portion is tapered, extending from the dome portion to tihe Lp pUrion. According to a further aspect, the cross-secton of the nasal locator in planes parallel to the plane of the tip opening is oval or elliptical throughout the tubular portion and upper parts of the dome portion 30 According to a further aspect, the ratio of the length of the rajor aixis of the oval cross section to the length of the minor axis of the oval cross section reduces, gradually extending from the tip of the tubular portion to ie base of the dome portion. According to a further aspect, the flow projecting axes of the two nasal locators converge at a location between 1Orm or 4l0mnim from the tips of the nasal locators.

- 16 According to a further aspect, the central xis of ie nasal locator, projected beyond the tips of the locators, converge to become closest at a location 10mm to 20mm beyond the tips of die nasal locators. According to a further aspect, if the tip openings of the nasal locators are projected on to 5 the coronal plane of a hypothetical wearer, the oval shapes of the rip openings are aligned to such that the major axes converge at an angle between 60 degrees and 120 degrees. In a fuRier aspect, the presen invention may badly le said to cotsit [i a patient interface compising: a frame and a seal, the seal including a paien-facng side with at least one patient opening and a frame-facing side with at least one frame-facing opening, the scal engaging 10 with the frame at a lip defined by the perimeter of the frame-facing opening, the frame including a front face portion in the region of a swivel connection to a supply conduit, the front face portion being inclined relative to the coronal plane of th- hypothetical wearet of the iterface such that the lower edge of the portion is closer to the coronal plane titan the upper edge of the portion, and the connector tuming flow from art entry to the connector to an exit of the connector through an 15 angle between 30 degrees and 79 degrees, the connector and the inclhied outward face portion of the mask frame together allowing fot free swiveling movement ef the conduit, the co.duit to adopt a position more or less paranel to the coronal. plane of the hypothetical wearer, and the connector rernaimng close to the face of the wearen According to a further aspect the connector does not inelade a bias flow vent 20 In a further aspect, the present invention may broadly be said to consist i a parent inter face comprising a Iruntic and a seal, the seal including a patient-facing side with at least one patient opening and a frame- racing side with at least one frarne--ficing opening, the seaI engaging with the Frame at a lip defined by the perimeter of Ie frame-facing opening, the frame including a supply opening through a front way of ihe name, a ring portion e:tending rom the front wall to 25 define a passage projecting from the inside surface of the front wall of the frame, and a projecting wal passing around the mntemally open end of the ring portion and engaging the lip of the seal, the trout wall of the frame and the ring portion, together with other porions of the frame, define a plenum chamber, with a bias flow vent through a wall of the plenum chamber, and an open area between the ring portion and the structure of the channel providing a flow path between the 30 interior of the seal and tie plenIn chambe According to a farther aspect, the bias flow holes are arranged through the wall of the frame in an area of the upper portion of the plenum chamber. According to a further aspect, the ring portion is formed as part of a first component of the frame, and the front wall of die frame is formed as part of a second component, the two 35 components being secured together to define the plenum chamber.

-17 According to a further aspect, the projecting wall comprises a channel, the channel receiving the lip of the seal. According to a uther aspect, the channel follows a closed curved path of overall width greater than height, such that the plenum chamber is predominantly formed to either side of the 5 ring portion. According toafirtler aspect, the ring portion connects to the upper and lower central pottions of the projecting wall and the flow path from the scal to the plenum chamber passes either side of the ring portion. According to a furilher aspect, re projecting wall is formed as part of the same component 10 as the ring portion. Accordmgn to a fur ther aspect, the bias flow vent is formed through the front wall of the second component. According to a firther aspect, the first component includes laterally projecting shield portions, the internal surfaces of the shield portions fitting against outer surfaces of an outward 15 wall of the seal to constrain the outward deflection of the seal. According to a further aspect, the second component includes downwardly and laterally depending stabilizers for stabilising on the upper lip region of a wearer According to a further aspect, the first frame component comprises a skeletal frame, with a least a portion of th1e stabiliscr parts of the component comprising an overmaoulded soft material. 20 In a further aspect, the present invention may broadly be said to consist inl a patient interface including a soft resilient seal, a rigid frame, headgear connecting to the frame, rigid projections at the connection of the headgear to the frame, the headgear being very floppy within 60mm of the frame, and, between this location and the projections, a soft portion, more rigid than the foppy portion of the headgear but made of a softer material than the rigid frame. 25 According to a further aspect, the projections are alike to prongs, long and slender. According to a further aspect, the soft portion extends firon the general path of the prongs. According to a further aspect, the projection is made up of a combination of a portion of the mask frame and a Cip portion of he headgear. According to ia further aspect, the soft portion is par of the headgear. 30 According to a further aspect, the headgear is a simple single loop strap. According to a further aspect, the projections project laterally beyond the breadth of the sea:. According to a narther aspect, the inention may consist m an interlace according to any plurality of the preceding paragraphs. 35 18 The term "cornprsing" is used in the specification and claims, means "consisting at least in part oft When interpreting a statement m iils specification and claims that includes "comprising", features other then that or those prefaced by the term may also be present. Related terms such as "comprise" and "comprises" are to be interpreted in the same manner. u In this specification where reference has been made to patent specifications, other exernal documents, or other sources of information, this is geneialy for the purpose of providing a context for discussing the Features of the invention. Unless specifically stated o therwte, rcfcrence to such external documents is not to be construed as an admission that such documents, or such sources of information, in any jurisdiction, are prior 'rt, or form part of the common general knowledge in 10) the art. BRIEF DESCRIPTION OF THE DRAWINGS Preferred forms of the interface will be described with reference to the accompanying drawings. One exemplary form will be described with reference to Figures 1 A and 1B. Behavicural 15 and sealing characteristics of this example will be described with reference to Figures 1C to lE Additional examples of the form of the inflating envelope will be descrtibed with reference to Figures IF to 11l An additional example of an interface with an alternaive franie is described with reference to Figure 1L A farther exarnple of an interface wihh an aitenative envelope and frame is described with reference to Figures 2A to 2C. Other examples of interfaces and pats of 20 interfaces, are described with reference to Figures 3 to 65. Figure 1A is a view fron above of an example interface including inflatable envelope, supporting feame, and straps. Figure 1 is an IMlstration shoving the interface of Figure 1 A in position on the head of a user. Figure ICA to 1CD are a sequence of illustrations showing irfation of the inflatable envelope. 25 Figure ICA shows the seal limp and deflated. Figures i CB and ICC show the envelope with progressively greater inflation, Figure 1C) shows the envelope inflated. Figures IDA to IDC show how the envelope retains a seal despite substantial vertical movement. Figure 1DA shows an intended position on the user's face, Figure 1DB shows a less than ideal position that might occur if the frame was moved upward. Figure 1DC shows a less than ideal 30 position that might occur if tre frine was moved downward. Figures lEA to 1EC show how the envelope retains a seal despite substandial lateral movement. Figure ;EFigure 1ELA shows an intended position on the user's face. Figure lED shows a less than ideal position that might occut if the frame was moved to the usets tight. Figure [C shows a less tian ideal position that night occur if the frame was moved to the user's left.

- 19 Figures 1FA to 1FEshow views of a number of interface variations. The interface Varations include variation of the shape of the envelope and the shape of the nasal locators. Figures TGA to JGE show views of a number of interface variations. The interface variations include variation of the shape of the envelope and the shape of the nasal locators. 5 Figures 1-LA to 1HG show views of a number of interface variations. The interface varLations include variation of the shape of the envelope, which are illustrated relative to features of a user's face. Figure 1I shows an interface with an alternative fame with a st.abilising serap. Figures 2A and 2B show views of a further embodiment of an interface with an inflatable 10 envelope and frame. The envelope is shaped to wrap around the user's nose in use. Figure 2C shows the envelope of Figures 2A and 23 with the frame removed. Figure 3a is a perspective view of pron wearing a patient interface. Figure 31) is a perspective view of the patient iterface of Figure 3a without the patient, Figure 3c is an exploded view lustrating the components making up the interface of Figure 3b. 15 Figures 4A to 4C illustrate, from different angles, a seal component of the patienL interface of Figure 3b. Figure 4A shows the seal component from an outward facing side: Figure 4.B shows the seal &tom a patient-a cing side aId Figre 4C shows a side view of the scal. Figure 5A is an exploded view of the seal and mask fame showing how they can be brought together to be assembled, 20 Figure SB is a side view of the interface of Figure 3b, partially disassembled to show the connection of an elbow to ihe mask frame. Figure SC is a front perspective view of the interface of Figure 3b lustrating assembly of the elbow with the mask frame, withn a gas wvai shoum vent present in the. elbow. Figure 6 i a from. view of the assetnbled seal and mask frame. 25 Figure 7A is a top view of the assenObled seal and mask frame. Figure 7B is a side view of the seal and frame of Figure 7A, uisectioned. Figure 7C is a view of the patient side of the seal of Figures 4-A and 4C. Figure 7D is a side elevation of the seal of Figure 7C, sectioned through line EE. Figure 8 is a side view of the seal and mnask frame of Figure 7A taken through line DD. 30 Figure 9A i3 a top view of the seal of Figure 7C, sectioned through line FF of Figure 7D. Figure 9B is a top view of the seal of Figure 7C, sectioned through line GG of Figure 7D. Figures 10A to 10C arc perspectve views illustrating a patient interface incorporating a number of inventions described in this specification. Figure 0A is a front view, Figure 10B is a profile view, and Figure 10C is a back view, -20 Figures 11A to 11H are -views of the soft seal component of the interface of Figures 10A to 10C. Rgure 11 A is a top view. Figure 11B is a front view. Figure I1C is a rear view taken from a position directly facing the open end of a nasal locator. Figure 11D is a cross section through section CC in Figure 11. Figure 11E is a cross section through line DD in Figure 11G. Figure 5 11 H is a cross section through line EE in Figure 11E. Figure 11G is a cross section through line CC in Figure 11E. Figure 1 IH is a cross section through line HMH in Figure 11E. Figures 12A to 12Fi are views of a flaime assembly of the interface of Figures 10A to 10C. Figure 12A is a front perspective view of the frame assembly. Figure 12B is a teat perspective view of the frame assembhy. Figure 12C is a side profile of the fraine -ssembly. Figre 1 2D is an assembly 10 viev of two components of the fra-ne assembly. Figure 112E is a back view of the frame assembly. Figure 12F is a front view of the frame assembly. Figure I2G is a cross secional side view taken through line AA, of Figure 1 2F. Figure 12H1 is a cross sectional top view, taken through lme BB in Figure 12F. Figure 121 is a rear view of an alLernative frame assembly having a different channel path for 15 securing the lip of' he seal. Figure 13 shows a further embodiment of an interface with an inflatable seal. The interface includes a seal body, frame, tubing and head. strap. Figure 14 shows the seal body of the interface of Figure 13. Figure 15 is a perspective view of the frame and seal body of the interface of Figure 13. 20 Figure 16 is a front view of the frame and seal body of the interface of Figure 13. Figure 17 is a side view of the frame and seal 'body of the interface of Figure 13. Figure 18 is a cross-seton of the frame and seal body througli BJB in Figure 17. Figure 19 is an akernative cross-sectional view of the seal body. Figure 20 is a cross-scelCon of the seal body through AA of Figure 16. 25 Figure 21 is an atermative embodiment ofta seal body of the interface of the present invention. Figure 22 is yet a further enbod-inet of a seal body of an1 interface of the present invention. Figure 23 is another embodiment of a scal body of an interface of the present invention. Figure 24 shows a first crmbodiment of a head strap that riay be used with an interface of the pescnt loyen tion. 30 Figures 24a and 24b show two alternative cross-sections of the head strap of Figure 24. Figure 25 shows a second embodunent of a head strap that may be used with an interface of the present invention. Figures 25a and 25b show wo alternative cross-secdons of the head strap of Figure 25. Figure 26 shows a third emhodirnent of a head strap that may be used with in interface of the 35 present invention -21 Figure 27 shows a fourth embodiment of a head strap thar may be used with an interface of the present invention. Figure 27a shows the extendible portion of the head strap of Figure 27 in extended and contracted conditions, 5 Figume 28 shows a fifth embodiment of a head strap tha may be used with an interface of the present nvenntion. Figure 29 shows a sixth enbodimCnt of a head strap that may be used with an interface of the present ImvVItion. Figure 30 Shows a first embodiment of the connection between a seal body and frame of the 10 interface of the present invention. Figure 31 shows a second emabodimntr of the connection between a seal body and frame of te: imrface of thle present invc.ntion. Figure 32 shows a third embodiment of the connection between a seal body and fame of the interacC of tie prese t irventon 15 Figure 33 shows a forth embodiment of the connection between a seal body and frame of the interface of the p-esct invention. Figure 34 shows a Erst embodiment of a brace that may be used with the interface of the present invention to fix tubing connected to LhC iterfacc Lo Lhe user. Figure 35 shows a second embodiment of a brace that may be used with the interface of the 20 present invention to fix tabing connected to the interface to the user. Figure 36 shows a third embodinieni of a brace that mnay he used with the interface of the present invention to fix obthing connected to the interface to the user. Figure 37 shows a fourth embodiment of a brace that may be used with the interface of the present invention to fix tubing connected to the interface to the user. 25 Figure 38 shows a fifth embodiment of a brace that may be used with the interface of the present mention to tox tubing connected to the interface to the user. Figure 39 shows a sixth embodiment of a brace that may be used with the interface of the present invention to fix tubingw connected to the interface to the user. Figure 40 shows a seventh embodiment of a brace Lhat mnay be used with the interface of the 30 present inviienion to fix tubing connected to the inteiface to dhe user. Figure 41 is a perspective view ofa suppor-ing collar. Figure 42 is a perspecic vicw of a patient wearing the supporting col of Figure 41 Figure 43 is a perspective view of the collt of Ftgure 41 front a different angle. Figure 44 is a front view of a patient wearing the collar of Figure 4-1. 35 Figure 45 is a top view of the collar of Figure 41.

- 22 Figure 46 is a t op view of a portion of the collar of Figure 41 illustrating a dome fastener connector. Figure 47 is a top view of a portion of the collar including an alternative fastener. Figure 48 is a top view of a portion of the colhr including an alternative fastener. 5 Figure 49 is a top view Of a portion of the collar including a further alternative fastener Figure 50A is a side view of a portion of the coar inclidirtg a securing dip in an engaged configuration. Figure 50B is a side view of the portion of the collar from Figure 50A in a disengaged condition. Figure 51A is a side view of a portion of the collar including a securing clip according to an S alternative eibudin t i. a disengaged condition. Figure S1B is a side view of the portion of the collar of Figure 51A in an engaged condition. Figure 52 is a perspective view of a terher depending from a porion of the collar, with the tether including a quck disconnect connector. Figure 53 is a perspective view illustrating a tether depending from the collar, the tether including i5 a quick disconnect connector which can also swivel. Figure 54A is a top view of a tether similar to the tether of Figure 5IB, but of minimal length. Figure 54B is a top view of the tehce of FigUre 54A with the quick release connector disengaged. Figure 54C is a side view of the tether o--f Figure 54A Figure 55 is an exploded view frustrating connection of a ring of the tether from the supporting 20 colRn to a conduitu Figure 56 is a perspcelive view of an interfitce including an alternative arrangement tot supporting the conduit from the patient. Figure 57 is a perspec tive view of a patient wearing an interface including a further altmative mrranigenent or supporting the conduit on the patient 25 Figure 58 is a side elevation of a frame and seal, the frame incorporating depending lip stabilisers in accordance wi[h a further invention herein. Figure 59 is a .op view of tae frame and seal of Figure 58, Figure 60 is a front view of the frame and seal of Figure 58. Figure 61 is a perspective view of an interface incoiporating the frame and seal of Figure 58. 30 Figure 62 is a graph of tested extension forces against exLensionI of sample strap materials. Figures 63A to 63C illustrate aspects of a preferred lea dgear of the interface of Figures 10A to 10C. Figure 63A is a perspective view of a portion of a headgear, including an end of a headstrap and a connector. Figure 63B is a top view of the strap and connector. Figure 63C is a view showing both (in cross-section) The connector and the socket of the frame assembly which receives 35 the connector in use.

- 23 Figures 63D to 631 illustrate another preferred headgear. Figure 63D shows a portion of the headgear, connector and a portion of the f-rame assembly to which it connects. Figure 63P. is a top view of the assembly of Figure 63D. Figure 6 3F is a sectional view tuough line AA of Figure 63E, Figure 63G is a side elevation of the strap portion and connector of Figure 63G. Figure 63h1 is a 5 cross-secdon through line BB of the connector and strap portion of Figure 63G. Figure 631 is an assembly drawing of an exploded view of the strap portion and connector of Figure 63G. Figure 63J is a perspective view of the strap portion and connector of Figure 63B. Figure 64 is a grailh of tested extension force against extension of another sample strap material. Figure 65 is a diagram illustrating a rest apparatus for measuring the flexibility of a breathing tube. 10 DETAILED DESCRIPTION According to one or more examples, an interface includes an inflatable envelope (that could also be deferred to as a bag or balloon) having a supple wall stmcture. The infatable envelope has a pair of locating prontsions that engage in the nostils of the user. 'Ihe locating protusions supply 15 gases flow to the user from inside the envelope. The envelope is so supple, and of sufficient dimension and shape, that when the inflated envclope is pressed agamst the face of a user, with the locating protrusions engaged in Lhe nostrils of the user, the envelope contacts the surfaces of the user's face (the nose, the upper hp and the cheeks) and provides a seaL One example of the interface will be described in detail. Many variations are possible to 20 both the scal part of the interface and to the supporting frame and straps. For example the seal part of the interface could be supported by the type of frames and straps that have been described previously for use with nasal niask, or nasal pillows interfaces. Though not explicitly described these variations are within the scope of this invenion Many variations on the shane of the envelope and the shape of the nasal locators are also possible without departing from the intended 25 scope of this invention. Some variadons are illustrated in Figures IF to IH. Figure 1A is a view from above of an example interface inCluding inflatable envelope, supporting frame, and straps Figure 1B is an illustration showing the interface of Figure 1A in posidon on die head 202 of a user. The interface includes a seal body 100. The seat body O includes a supple envelope 102. 30 When infated te s upple envelope 102 has a general blob shape with a substantially uniform aspect ratio. The envelope has a low wail thickness. The envelope is formed from a material having sufficient elasticity and yield strength that the combination renders the envelope supple. The envelope is capable of repeated drastic deformations without failure. Possible materials include latex, vinyl, silicone and polyurethane. Typically wall thickiess would be below 0.5mm and could 35 be lower than 0.2nmn.

-24 The seal body includes a pair of nostril locators 104 protruding from the envelope. Preferably the nostril locators are formed integral with the envelope. Each nostril locator includes an outlet aperture for supplying gas from inside the envelope to a user wearing the mterface. The scal body may broadly be shaped to have a sidewall 108 and a seal surface 110. The 5 sidewall 108 extends all around the body. In use either or both of the sidewal 108 and the seal surface Ii 0 may press against surfaces of the user's face to form a seal that conforms around the nose and surrounds the nostril locators. The nostril locators may or Tuay not be fonned to also seal with the nostrils of the user. The seal body 100 includes an inlet opening at the bise approxiateiy opposite the nostril 10 locators 104, The seal body may be formed, for example, by couatng Over a nale oloind. Coating may be performed by spraying the desired material over the male iould 1n a sequence of coats, or by dipping the male mould ino a bath of the desired material one or inore times to build up the desired. thickness. Apertures in the seal body (for example for the outlet apertures in the nostril 15 locators) may be subsequently cut. The seal body nay be pressure tested prior to cutting the apertures. A substantial extent of the seal body or envelope Is suppte. This is except for a region immediately adjacent and including the nostril locators and immediately adjacent and including the inlet openg. These areas must have some shape and can be of any suitable stiffness it is 20 preferred that thesc areas are stiffer and as such they may be funded of a thicker material or shily formed thicker in the same material as the rest of the envelope. The envelope may be so supple diat when not pressurised with gases the envelope, bag or balloon hangs lirnp and does not hold its shape. However, in son etmbodiments it is required that the envelope retain some shape when not in use (not pressurised). Therefore, die envelope may 25 have sonie natural shape. For an example., see the embodiment of 2A to 2C. The seal body 100 is .unmorted by a frme 112. The ilet openiag of the seal body is fted to the frame, or directly to a conduit extending through the frame. The frame 112 is preferably a minimal design to provide little visual obsrnuctions, slowing a clear field of view and allowing the user to wear glasses while wearing the interface. Preferably ie 30 frame is forced frorn an elastomeric material. This allows the frame to flex to confirm slightly to the user's face, wheil still providing support for ite seal body Lo keep the s al effectively against the face and around the nose of the user. The frame may be formed by injection moulding, preferably from an elastomeric material such as silicone or polyuredhare. -lowever, mote rigid materials may be used.

- 25 Ihe frame presses the inflated seal body against the face of the user right out to the periphery of the frnme. For example a nasal ridge of the ftanm:e tray press the uppermost periphery 200 of the compressed seal against the ridge 216 of the nose of the user. Side peripheral portions of the frame press side peripheral pordons of the seal body against the lower cheeks of the user. The preferred fs-rtae includes connection points for connecting straps 126 to the frame. The strap attachment points provide for anchoring the straps, and preferably for adjusting the strap lengths. In other fimis the envelope may include integrad strap attachncut points. These attachments may be points on the surface of the envelope. However, they could be integral straps 10 or wings formed in the envelope that extend out either side of tihe envelope. The strap attachment points are similar to those described above in Figure IA or IB, but formed on die envelope. The interface is intended to be supported by a single strap 128 passing around the back of the head. To improve stabity of the frame on the face the straps 126 are bifurcated at the forward ends of strap 128. Each end of strap 128 divides at location 134 into an upper strap 130 and a 15 lower strap 132. The straps may be formed from an ielasti or elastotneric material,. Fot example suitable sttap materials mar include a woven elastic stip or a narrow strip of Foam and fabric, such as Breathoprene t . The strap extending around the back of the head provides pressure on the mnask and helps seal the envelope to the user's face. The connecton points on the frame may include owner connection points 122 for receiving 20 lower strap ends 132, and upper connection points 120 for receiving upper strap cnds. The connection between frane and strap may be by any Suitable buckle, strap bar or clip. In the illustrated enhodiment the connection points are provided close to the extreme side JnUiS of the frame. In the illustrated ctbodimncat of Figures 1A and 113 the frame includes iaterally extended 25 supporting arms 124 that can press on the lower cheek portions 214 of the user, possibly outside tie periphery of the seal body. The side arms 1224 are flexible, but stiffer t thatie seal body or sra ns Ihe lower strand connection points are preferably provided at the extreme ends of the suppornng arms. 30 The support arms may be provided wit some cushioning on their inside surface to contact the user's face. The cushioning could be formed from silicone or from a foam material. A web 218 of elastic material may span between the flexible suort arms 214 atnd tie upper connecuon poits 122. The web provides support to the inflated envelope, pushing it against the face to create a moble seai in the side peripheral region. The web may be thin relative to the 35 rest of the mask frame.

- 26 A flexible tube 114 extends from the frame 112. The flexible tube delivers breathable gas. The distal end of the flexible tube 114 connects to the main CPAP delivery Ubc 212, for example at connector 210. The flexible tube 114 is Preferably made of breathable material such as that tube constrctior described in US6,769,431 and US7,140,366, except the tube 114 is an inspiatory 5 conduit nor expiraryn limb. The contents of US6,769,431 and UST5,140,366 of Fisher & Paykel Healtheate Limited are incornorated herein by reference. A lanyard 204 may be connected to te distal end of the flexible tube 114, the connctot 210 or the delivery be 212. The lanyard is to be connected to the body of the user of the interface. For example the lanyard may be wom around the neck 206 of the set. Jhe lanyard 10 cartics the weight of the main delivery tabe allowing less pressure to hold the interface in place. This may allow a single head strap to hold the interface in place. The lanyard may connect to the conduit, for example, by a clip 208 [ha clips into a corrugation of the conduit. Preferably dhe lanyard or tether is connected to the conduit at a location between 10cm and 50cm from the frame. 15 A connector 116 may connect the rube and die frame. The connection mechaniin imay be any suitable connection. This could include a snap fit, hooks in to the silicone, keyhole inserts, over moulding insert moulding, screw attachments or glung, or any combination. The connector 116 may include a limited flow oudet (ox bias flow ourder) 220 fot providing gas washout from the interface. The outet 220 may be in the form of a collection of small 20 apertures in the connector. Internally the connector may include a funnel or extension leading from the vent into the mouth of the envelope. The frame may have any tutable arrangement for securing the envelope. An example is an annuiar wfl extending from tihe inside of the Frame around the perimeter of an opening that extends to the connector 116. The wall includes an outwardly extending lip. The inlet opening of 25 the envelope engages over the outwardly extending lip of the valL The inlet opening of the envelope is preferably stretched to fit over the lip. The inlet opening of the envelope may be provided with a thickened or reinforced wall second, for e.:ampic by rolling up an extended section of the envelope. Alternative the envelope may be fitted with one part of a connector (for example by 30 adhesive o ver noulding), and the frame of the end of the conduit may include a complimnentary connector portion. The frame could be varied substantially and still provide suitable support for the inflatable envelope. The frame could include fewer or additional supportmg arms against the face. The frame could incorporeate rigid bodies to provide better support. The frame could incorporate a swivel or 35 ball joint for the flexible conduit to allow rotation through different angles and orientations. The - 27 frame could include mechanisms to adjust size or shape or both to different users. The frame could support more than one inflatable envelope. The interface could include more straps to provide support around the user's head. 'The frame and straps could he moulded from a continuous body of elastomeric material. 5 Figures ICA to 1CD art a sequence of illustrations showing inflation of dic inflatable envelope. Figure 1CA shows the scal 300 limp and deflated. The side wail and scale portion of the seal body are collapsed toward the inlet perimeter 303. Figure 1CB shows the envelope 302 slightly inflated 10 Figure 1CC shows the enivelope 304 finrther inflatecd Figure lCD shows the envelope 306 inflated to sub'stantiallv the final Orim in which the internal pressure supports the shape against the effect of gravity. This shows the nostril locators 104 protruding and aligned, ready for positionig in the user's nostuls as the nrst step in donning the interface. 15 When inflated without stretch the envelope will rot pass through a circular aperture of 40mrn diameter without contact. When Lhe envelope is inflated it holds its shape with an internal pressure equivalemt to 3cm

H

2 O. The next stage in doling the interface is to press the frame toward the face to compress 20 the seal body around the region of the nose. 'The user then passes the strap over their head to hold the frame in place, pressing against the seal body. In use the frame may move relative to die head of the user. This may result from mnovemerts of the user during sleep changing the shape of their fare or the orientation (and therefore gravity effects) of the interface, forces on the conduit connected to the interface hugging 25 at the frame, or forces directly applied to the frame or straps. Figures 1DA to i)C show how the envelope retains a seal despite substantial vertical movement of the frame relative to the head. 'The wall thickness of the seal body is exaggerated for clarity, The seal is retaied by the seal body conformmg to the user's face to retain a sealing area. The seal body conforms to the user's ace dIe . the suppleness and extent of ite envelope, 30 together with the treatment pressure inside the seal body pressing the seal body against the facial contours. Figure IDA shows an inLended position 402 of thde seal body relative to she users face. The position and orientation of the frame (which is nor shown) is indicated by the inlet 400 of the seal body. The upper seal portion 424 of the seal body is wrapped around the tip of the nose 418 The 35 lower seal portion 422 of the seal body is pressed against the upper lip of the user.

Figure 1DB shows a less than ideal position 404 of die seal body relative to the user that might occur if the frame was moved upward as indicated by arrow 408 The mure ideal position 402 is shown in ghost for comparison. The upper wall seal and wall portion 428 has toiled upward. The seal now extends to a higher location 416 on end of the nose. The lower wall seal portion 426 5 has pealed somewhat away from the upper lip of the user, but the abundant supple material still -maintains a seal lust below the nose at 414. Figure DC shows a less than ideal posidon 406 of the seal body relative to the user that might occur if the frame was moved downward as indicated by arrow 410. The more ideal position 402 is shown in ghost for comparison. The upper seal portion 432 has roled upward, pealing way 10 from the tip of the nose, but the abundant supple material still irkaituains a scal ai: 420. The lower wall seal portion 430 now covers the upper lip, and mamtains a seal at 412. Figures lEA to 1EC show how the envelope remains a seal despite substantial lateral movement of the frame relative to the head- The wall thickness of the seal body is exaggerated for ciarit The seal is retained by the seal body conforming to the user's face to retain a sealing area. 15 The seal body conforms to the user's face due to the suppleness and extent of the envelope, together with the treatment pressure inside the seal body pressing die seal body against the facial contours. Figure 1EA shows an intended position 500 of the scal body relative to the user's face. The position and orientation of the fame (which is not. shown) is indicated by the ianlet 400 of the seal 20 body. The left and right side seal body portions 510 and 520 respectively cover the cheeks to an ecual extent on each side of the nose. Figur EB shi-ows a less than ideal position 502 that might. occur if the frame was moved to the user's right, as indicated by arrow 506. The left side portiR 510 of the sea: has peeled away from the face at region 526, but still retains a seal in the region of lie nares. The right side portion 25 of the scal has rolled out to cover additional area 522 of the righr cheek of the user. Figure IEC shows a less than ideal position 504 that might occur if te frame as moved to the user's right, as indicated by arrow 508. The right side portion of the seal has peeled away ftron-i the face at region 524, but st1l retains a seal M die region of the nates. The left side portion 510 of the scal has rolled out to cover additional area 512 of the left cheek of the user. 30 One inflating seal according to this invention has been particularly described above. A range ofvarianons, that is by no means the limit wiithe scope te inenon are illustrated in Figures 1 E to 1-. These variations display a range of individual features that rnay be selected and combined in many combinations. The combinations illustrated are selected only for eemnpiftication and other combirations are also possible.

- 29 Figures IFA to 1EE show views of a number of interface variatons. The interface variations include variation of the shape of the envelope and the shape of the nasal locators The seal body of Figure IFA includes nasal locators that are shaped to locate in the nares. The locators 600 include a bulge 602 between where they join the envelope and their outlet ends. 5 The bulge helps secure the locators within the nares on inflation with internal air pressure. The narrower base where they join the envelope increases flexibility. The seal budT of Figure IFB includes nasal locators that are shaped to locate against the nries. The locatot-s 604 include a flange between where [hey join the envelope and their oulet ends. The flange is broader than the nares opening and presses against the lower surfaces of the 10 nse. The :lflgc is pressed against tbc naces by inflation with ilternal air prsstuc. The narrower base where they join the envelope increases flexiblity. The narrower tip portion 608 locates inside the nares to locate the seal body. The seal body of Figure IFC incirtdes nasal locators 614 !tat are shaped to locate in die nares The locators 614 include an alternating series of gussets 616 and ridges 618 adjacent their 15 outlet ends. The gussets assist the locators to expand on inflation with internal air pressure. The seal body of Figure 1FD includes nasal locators that are shaped to locate in the nares. The locators 620 have a wide base 624 adjacent the envelope and taper to a narrow tip 622. The narrow tip allows for an easy ft ino the naxes. Tie flaed base portion 624 provides a comfortable transition to seal in the oares. 20 The seal body of Figure lFD also illustrates the possibility of providing one or moe areas 634 of the envelope shaped to deform in a controlled manner when the seal is compressed against the user's face by the frame. Prefi:raly these areas deform in a predictable way that assis the seal to maintain seal as the frame moves relative to the face. The seal body of Figure 1FF includes nasal locators that are shaped to locate in the nares. 25 The locators 626 include a buige 628 between where they join the envelope and. their outlet ends. The bulge helps secure the locators within the naves on inflarion with internal air pressure. The narrower base 632 where thc join the envelop incraes ilcxibility. The locators 626 also include one or more gussets 630 to asit the locators to expand when inside the nostrils. The seal bodies of Figures IFC to 1FD have -a substanially triangular seal surface 610 to 30 increase the amount of supple seal material available to cover the user's nose. The seal bodies of Figures 1FA to 1FB have a more oblong or oval shaped seal surface. Figures 1GA to 1GE show views of a number of interface variations. The interface variations include variation of the shape of the envelope and the shape of the nasal locators. The seal body 700 of Figure 1GA includes nasal locators that are shaped to locate in and 35 against he nares. The locators 720 have a wide flange 722 adjacent the envelope and taper to a 30 narrower tip, The tip fits into the sares, The Dared portion 722 presses against the lower surfaces of the nose. The nasal locator may have a short stalk recessed. inside the envelope- The stalk provides flexibility. The seal body 702 of Figure 1GB inchides nasal locators that are shaped to locate in and :i against Lhe nares. The locators 724 hare a wide flange 726 adjacent the envelope and taper to a narrower tip. The tp of locaror 724 is narrower than the tip of locator 720 of Figure 1GA. The narrow tip fits into the rares. The flared portion 722 presses against tWe lower surfaces of the nose. The nasal locator may have a short stalk recessed inside the envelope. The stalk provides flexibility. The seal body 704 of Figure 1GC is like the seal body of Figure 1FD except for an ovoid 10 forn rather than a triangular form. The locators 730 have a wide base adjacent the envelope and taper to a narrow tip. The narrow tip allows for An easy fiL into the nares. The flared base portion provides a comfortable transition to seal in the naies. The scal body 706 of Figure 1CD includes nasal locators that are shaped to locate in the nares. The locators 712 are gently flared to their base. The locators 712 have oval outlet apertures 15 716, which match the typical anatomic shape of the nostril entrance. The ovals may he angled relative to each other. The flared base portion may be steeper on the inward facing wall and than the outward wall The seal body 708 of Figure 1GE is like that of Figure lGD. The nasal locaetrs that ate shaped to locate in the nares. The locators 714 are gently Eared to their base. The locators 718 have 20 oval outlet apertures 716, which match the typical anatomic shape of the nostril entrance for a larger nose. The ovals may be angled relative co each other. The flared base portion may be steeper on the inward facing walR and than the oi twarid wall. The seal body of Figure IGC also illustrates the possibility of providing one or more areas 728 of the envelope shaped to deform in a controlled manner when the seal is compressed against 25 the user's fae by the framc. Preferably these areas deform in a predicable way that assists the seal to maintain seal as the fime moves relative to the face. The seal bodies of Figures 1GD and ICE have a subsantially triangular seal surface 710 to increase the amount of supple seal material available to cover the user's nose. The seal bodies of Figures 1 GA to 1 GC have a more oblong or oval shaped seal surface. 30 Figures 11-IA ro IHO show views of a number of Interface vaiations. Tle interface variations include variation of the shape of the envelope, winch are illustrated relative to features of a user's face, in the form they would take under compression by the interface frame. The envelope 800 of Figure IHA is shaped to have a smaller overall size which seals generally around the bottom of the nose and the nares. The small minimal form still confornms to 35 the user's face due to the CPAP delivery pressure inside the body. However, the limited lateral and - 31 vertical extent of the envelope means it will not retain scal through as large displacement as others illustrated. The envelope 802 of Figure 1HB is shaped to have a larger overall size to encompass more of the area around dhe nose. Tihe larger extent of the envelope suggests it will retain seal through 5 larger displaceiments than the seal of Figure I HA. 'The envelope 804 of Figure 1 IC is shaped to have a larger lateral size to accosnmodate users with wider rnses and provide more hateral support. The larger lateral extent 812 of die envelope suggests it wili retain the seal through larger lateral displacements than the seal of Figure 1HA, Also, the lack of seal over the user's nasal bridge 807 means there is no pressure on the 10 user's bridge, increasing the user's comfort in that area. The envelope 805 of Figure 11ID is shaped to be more upwardly extended, with a definite protruding portion 814. The protruding portion 814 wraps over the nose ip and around the sides of the nose to accommodate longer noses. The envelope 806 of Figure u-E is sized to encompass the whole nose having more 15 vertical extenL 816 and more lateral extent 813 than de envelope of Figure 1IA This envelope may require a larger and more extensive frame to provide a wide seal. The envelope 808 of Figure t-1F includes a downwardly extending portion 820 that covers the moth of the user. This downward extension may include an oral interface portion for supplying uerapy orally as well as, or instead of, nasally. 20 The envelope 81 0 of Figure 1IG includes wing portions 822 that exemplify the possibility that the seal body could provide cushioning tinder extended pars of the frame. for example the wing portions could provide cushioning under the support members 1 2 of the frame of Figure IA. These variations of envelope shape and variations of nostril locating member are provided. 25 for the pupose of illustrating a range of possibilities hat would be applied to the 1iftable seat. The inflating seal concept is iiended t encompass these and other variations. Figure I- shows a further alernative ernbodirrent of ar interface. The interface 900 has a sea' body and supple envelope 901 of any of the embodinents described above. The envelope 901 has a fame supporting it. [he frame 902 cmps about the envelope 901. 30 Extending above the frame 902 and envelope 901 is a strap. The strap 903 furher stabilises the envelope 90L Particularly, the strip prevents the envelope extend'incg out too far from the user's Face and causes the envelope to be pushed against the user's face and more partcularly the user's nose. Th.e strap is made from a flexible aerial similar to that of die frame, but can be made with any siffness as required. Therefore, a more stiff material could be used, or a substantially more 35 flexible material than the frame.

- 32 The frame has bias flow holes 904 formed about a connector for the conduit, providing gases to the interface, The bias flow holes 904 provide gas washout from the interface. A single head strap 905 extends about the usefs head in use. The head strap 905 attaches or either side of the user's head to connectors 906, 907 formed in the frame. The connectors 906, 5 907 are forced in laterally extendin SuppOrt arms 908, 909 of the frame. In other farms the strap 903 may be formed in the envelope 901. In this form, the strap is integrally formed in the envelope and provides additional stability to the envelope. Therefore, in effect the integral strap forms an elongate strip in the envelope, the strip extending in an arc above the &ame. 10 Figures 2A to 2C show a furthcr example of n mterface with an inflatable envelope, bag or balloon. The interface includes a seal body 940. T[he seal body 940 includes a supple envelope 941. The seal body 940 has a curved shape to match the contours of a human face, The seal body 940 has an inner surface 9-42 and an outer surface 913. The inner surface 942 includes nostril loeators 944, 945. The nostril locators 944, 945 each have outlets to allow gases to pass to the user. 15 In use, the inner surface 942 presses against the uses face and the nostril locators 944, 945 extend ito or sh about the user's nostrils. The seal body 940 is shaped to wrap around the user's nose. The seal body 940 has side portions or wings 946, 947 that extend completely over the sides of the user's nose and may also extend at least partially over the uses cheeks. The seal body 940 is missing in the region of the 20 user's nasal bridge. So effectvely, there is a cut out region 948 in the seal body. The cut out region 948 means in use the seal body does not put pressure on the user's nasal bridge region, a common area of comp>laint by users of interfaces that extend over a user's nasal bridge. The scal body 940 includes an inlet opening 949. The inlet opening 949 is opposite the nostril locators and receives a frame 950. The frame 950 is curved to match the seal body and 25 provides support to the seal body. The frame 930 includes a connector 951 that attaches in use to the tubing (for example tubing 114 as shown in Figures I A and 1B) that receives pressurised gases for supply the user. The frame 950 is made from a plastics material. 'The plastics material may be a flexible material or maybe a more rigid type material. For example, the f&amne may be made from a 30 polycarbonate. Or the frame could be made frorn a more flexible material such as silicone, In use, the interface of Figues 21A to 2C is supphed via tubing and the connector 951 on the frame 950 with pressurised gases. The gases inflate the seal body 940 and cause it to press against and about the uses nose. The nostril locators 944, 945 are caused to seal in or about the users nostrils and the pressurised gases pass through the locator oudets mto the users nostils.

- 33 The frame or seal body includes at least two strap connectors similar to those described above. The connectors allow a head strap to be attached to the interface 940. The head strap will extend about the back of the user's head and provide additional tension on the intrfaee to hclp with the sealing of the intrface on the user's face. 5 The seal bock is made from a flexible mTaiterial :xamles of possible materials include .atex, vinvl., silicone and polyurethane. In a preferred fonm the seal body's outer surface is made fron a thicker material dian the iner surface. In this way die sea body has a better ability to hold a predetermined shape. 10 With reference to Figures 3 to 65, the inventions described relate especially but not enclusively, to an interface that includes an inflatable nasal seal having a supple wall st tuemre Figures 1 0o2 described above disclose other fortn-is of sends of tlis ty pe. The inflatable seal may have a pair of locating protrusions that engage in the nostrils of the user. The locating protrusions supply gases flow ro the user from inside the seat The patient side I5 of the seal may he so supple, and of sufficiem dimension and shape, that when the inflated seal is pressed against the face of a user, wih the locating protrusions engaged in the nostrils of the user, the seal conf orns to the surfaces of the user's face particularlyy the sides of the nose and the upper lip) and provides a seal. An outwardly facing wall of the scal tmay be more rigid, and support the inner wall of the seal in a position wrapped around the wearer's rose. 20 The seal is formed from a material having sufficient elasticity and yield strength that the combination renders the envelope supple. The supple portion is capable of repeated drastic deformations without failure. Possible materials include late, vinyl, silicone aid polyrerhane. Typically wall thickness of the supple portions of the seal would be below 0.5mrn and could be lower than 0.2nm., 25 The seal body ircudes a pair of nasal Iocators protruding fron the patient facing wail. Preferably the masai locators are formed integral with the seal. Each nasal locator inclIudes an OLt aperture for supplying gas from inside the envelope to a user wearing te interface. The seal body includes an inlet opening, approximately opposite the nasal locators. A substantial extent of the seal body or envelope is supple. A region adjacent and inchding 30 the nasal locators and a region adjacent and including the inlet opening are much stiffer. These areas hold the overall shape of the seal and can be of any suitable stiffness. These areas may be ftinned of a stiffer material, or formed thicker in the same material as the rest of the envelope. The seal is supported by a mask body or frame. The inlet opening of the seal is fitted to the frame, ordirecly to a conduit extending through the frame.

- 34 The frame is preferably a nunimal design to provide ittle visual obstruction, allowing a clear field of view and allowing the user to wear glasses while wearing the interface. The frame may be formed by injection moulding, for example from an elastomeric material such as silicone or polyurehane. Aircnaively., more rigid materials such as polycarbonate, or polyester, polystyrene or nylon may be used. The preferred frame includes connection oints for connecting straps to tbe frame. The strap attachment points provide fot anchoring ti straps. In other forns the nasal seal body may include inegral straw atachment points. These attachments may he connection elements on the surface of the envelope. However, they could be 10 integral straps or wings formed in the envelope that extend out either side of the envelope. The interface is intended to be supported by a single strap passing around the back of the head. The strap may be formed from an elastc or elastomeric material. For example suitable strap materials may include a woven elastic strip or a narrow senp of foam and fabric, such as BreathopreneM. The strap extending around the back of the head provides pressure on the mask 15 and helps keep the seal against the user's face. A preferred strap according to one or more inventions herein is described later in this specification. A flexible tube extends from the frame. The flexible tube delivers breathable gas. The distal end of ibe flexible rube connects in the main CPAP deiverv tube, 20 A connector may connect the tube and the frame, The connection mechanism may be any suitable connection. This could include a snap Fit, hooks into the silicone, keyhole inserts, over moulding, insert moulding, screw attachments or ghii, or any combination. The connector tray inchlde a limited flow outlct (or bias flow outlet) for providing gas washout from the interface, The outlet may be in the form of a collection of small apertures in the 25 connector, internally the connector may include a funnel or extension leading from Lhe vent into the mouth of the envelope. Alternatively, the connector may not include a bias flow vent, Figures 3A and 3B illustrate an example patient iterface incorporatng inventions disclosed in this application. For clarity, the patient interface is shown separate from thc paiit in Figure 3B and as worn by a patient in Figure 3A. 30 The patient interface 101 broadly includes a mask 103, a strap 104 for securing the mask to the patient, a flexible supply conduit 107 connecting to the mask 103 and a conduit support strucre 109 which attaches to a patient and supports t11c weight of conduit portion '107 ard of any connected conduit supplying gases to the 3ilet end I11 of conduit portion 107. Particular aspects of this patient interface, and variations on each aspect, will be (or have 35 already been) discussed wish reference to other Figures. An interface may incorporate some -35 aspects but not other aspects. For example. an interface might incorporate aspects of the mask while using a different arrangement for securing the mask to the user., An interface might include a different mask while using inventive aspects of the strap to secure that: mask to the user, An interface may incorporate aspects of the mask but not make use of a similar, or any, structure tor 5 supporting the weight of the conduit from te body of the patienL Al of these variations arc considered within the scope of this application. Referring to Figure 3A, the mask 103 fits over the nostrils of the patient and includes lateral portions which curve around either side of the nose. These lateral potions provide for forcing a perimeter seal on the ouLtwardly facing surfaces of the flanks of the nose. The strap 105 passes 10 around the user's head in a simple loop above the user's ears. The conduit portion 107 depends from a central connection 113 at the frnt of mask 103. The central connection 113 is preferably a swivelling elbow so that the path of the conduit relative to the positioning o f the mask on the face of the patient can adapt to the sleeping position of the patient. The swivelling elbow may be in the form of a baE joint so that the elbow cart pivot about 15 axes paraiel to and perpendiccuar to its connection wirh the mask. The illustrated conduit support 109 comprises a collar 115 connected around tie neck of the user. A tether 117 connects between the collar and the conduit 107, The component parts of this exemplary interface are ilustrated in Figure 3C. 'Ihe mask 103 includes a seal 301 and a body or frarne 303. The sem and body are ilustrated m more detail in 20 Figure 5A.. Their engagernent will be described in more detail with reference to Figure 5A and Figure 8. The body 303 includes a socket 305 and connector portions 307. Socket 305 receives an engagement portion 311 of elbow 333. Elbow 333 is connected to the end of a length of flexible tubing 315. The other end of flexible tubirg 315 is terrnuiated with a cuff 317. Connectot 25 portions 307 of mask body 303 are for engagement with connector portions 321 of the head strap 105. The head sTran 105 inicldes c single length 323 of stable material. Connector ponion 321 are provided at either end of the length 323. The collar 1 15 includes a band 325 of a material intended to be comfortab.e when worn during periods of seep. The bid incddes a frst adjustable connection 327 arid a second non 30 adjustable connection 329. At the adjustable connection 327, free ends of the band overlap, and the degree of this overlap may he uaried to a desired amount and fxed at this desired amount. At the non-adjustable connection 329, free ends of the band may simply be secured or released. Once the adjustable connection 327 has been adjusted, the collar may be opened for fitting to the patient or removal from the client and secured after fitting to the client, by disconnecting or connecting 35 the non--adjustable connection 329. The non-adjustable connection 329 rnay be a quick release connector that disconnects with applied tension widin predetermined range. This ensures that the collar w il telease without injuring the patient if any adverse iuation arises. The tether 109 includes a first portion 331 attached to the collar and a second pordon 333 which attaches to the conduit. These portions are preferably releasably engaged hy another quick 5 release connector, wich preferably disconnects on application of a tension within a predetermined r~ange The tether portion 333 connects to conduit 315. The tether portion 333 includes a potion of the quick release connector and a fitting 337 that engages the conduin- The fitting 337 may be an open clip to engage a corrugation of the conduit, or a recess of the cuff 317, or to engage 10 around the general cyllndrial shape of the conduit or to a cylindbcal portion of the cuafE, .A.lternatively, and as illustrated, the portion 337 may comprise a tng that fits around a portion of the. conduit, or a portion of the cuff. In the illustrated embodiment, the ing 337 is captive between the cuff 317 and a connector portion of a swiv el 335. The dag flts over a portion 339 of cuff 317 and is held captive by an end portion 341- of the swivel 335, which has a larger diameter 15 than the internal diameter of the ring. The extemal form of a preferred seal is illustrated in Figures 4A to 4C. The scal 301 includes a patient-fiacing side, broadly illustrated in Figure 4B, and an outward-facing side, broadly llustra:ted ins Figure 4A. A pair of nasal locators 401 protrude from the patien-facing side. Broadly speaking, the wal of the scal foming the patentFacing side is very supple with the 20 exception of the nasal loentors, the area immediately adjacent the nasal Lactrs,7or both. V aniatons n the suppleness will be described in more detail with reference to the cross sections ilustrated in Figure 7D, Figure 8 and Figure 9A and 9B. In overall form, the seal leas a central portion irludgin nasal locators on the patient-facing side and an opening 403 on the outward-facing side. The extent of this central portion 407 IS 25 broadly indicated by broken line 409 in Figures 4C and 4A. Fur ciariny. broken line 409 is also inched in Figure 7A which comprises a top view of the ruask portion of the inerface. Lateral or side portions 111 extend from the central portion 407. Each side portion includes an outward face 413 and an inward face 415 and a peripheral cdge portion 417 that joins the inward face portion and the outward face portion. The peripheral edge portion 417 extends 30 around a top edge 419, an end edge 423 and a lower edge 421. Accordingly, considered frin inside the seal, the side portions 411. resemble a pocket. Each side portion is guite extensive. Preferably, the side portion extends greatel:r-n 10mm (most preferably greater than 20mm) or at least a distance 70% of the distance separating the centres of the nostil locators 401 beyond the base of each nostril locator.

At least the inside wall 415 and the perimeter wall 417 of each side portion are very sIpple, so that tey can conform to contours of the user's face, and in particular, to contours of die outside of the sides of the aser's nose. At least portons of the outside facing wall 413 of the side portion are also supple, but may he progressively less supple moving toward the central portion 5 407. The central portion 407 of the seal includes opening 403 to pass a gases flow to and from the mask body 303. The opening 403 may include features such as lips and/or channels to engage with features suc as channels and/or bps on the body 303. The opening 403 may be formed with clip portions, or clip portions may be attacked to or over-rnoulded to the perimeter of the opening 10 403 to facitate engagement with the frame 303. Typicaly, the opening 403 wil be substantially thicker and more rigid than the supple sealing portions of the sea 301. The opening 403 should be at least die size of the interior cross section of the supply conduit 315. Preferably, and as ilhttated, thet opening 403 is comncsuratc wth the extent of the body 203 .f the mask, this extent being commensurate with dhe general width of the interface and approximately with the 15 width of the nose of the intended wearer. In he preferred form, he interface is tended to be of small size and the body portion 303 of the mask curves to follow approimnatelv the contour of the upper lip of the wearer, and the seal is formed such that the openimg 403 follows his approxanate curve, in plan. The central portion -107 of the seal exteclds above and below thc opening 403. Above the 20 opening 403, and the nostril locators 401, the central portion includes an outer-facing wall 431, and inward-facing wall 433 and a penmeter portion 435, At least the inwardly-facing wall portion 4-33 and the ontwardy-facing portion 435 are preferably Ihin and supple, Below the opening 403, the central portion 407 includes an outer wall portion 441, an inner wall portion 443 and a peripheral portion 445. At least the inner portion 443 and the perip)herai 25 portion 445 are preferably thin and supple. In use, the supple interior wall portions above, below and to each side of the nasal locators are inflated by' pressure inside the seal (from the flow of gases supplied to the patent interFace) to press against the skin of the wearer and conform to the contours of the outside surfaces of the nose of the wearer and to the surfaces of the lower face of the nose of the wearer and to the 30 surfaces of the upper lip of the wearer immediately below the nose, Movement of the mask body does no break this seal, as the supple perimeter or periphery of the seal allows the mask body to move in the direction of movement to at least a small extent. The supple perimeter de-couples the position of he nostril locators ftorn the position of die rask body, allowing the mask body to displace both laterally and vertically (relative to axes of the patient's face). ThIe side portions 411 -38 engage the sides of the patient's nose, and form some additional seal against them and support the location of the mask. The mask body and seal are illustrated in larger format iM Figue 5A and in Fgures 5B and 5C. As previously described, the seal includes opening 403, with arrangements to secure the seal to 5 the mask body. The mask body includes a socket 503 for connecungwi thte supply conduit, and a seal opening 501 for engaging with the opening 403 of the seal. The seal opening 501 aRd the opening 403 of the seal are provided with conplementary features to engage them together. In the ilaLtred fCmi, the seal opening 403 includes arrangement 507 of lip and channels, and the periphety of the scal opening 501 of the mask body includes a complementary arrangement of 505 10 of channel and ups. The arrangement of channels and lips is devised to ensure that when the seal is properly frted to the nask body, and supplied with gases uider pressure, there are no leaks at this join Many other ways can be devised for connecting the seal and the mask body and this arrangement is only illustrative In die mask body, the outlet opening 501 to the seal ir directly opposite the opening of 15 socket 503, so that the opening 503 is centrally located. Either side of socket 503 extends a central side portion 509. The central side portion ) 509 may be a plain covering wall, enclosing a portion of the opening 403 of the seal The central side portions 509 may include small apertures as part of a gas washout vent, In the preferred embodient illustrated, side anns 511 extend beyond the extent of the seal 20 opening 501, best ilbutrated in Figure 7A, the side arms 511 preferably extend beyond the extreme width of the seal. Each side arm 511 includes a connector portion 513 for connecting to connector portion 321 of the strap. In the illusurated ermbodimen, the connector poisons comprise a securing post with a perimeter undercut_ The strap has a small loop formed at each end which stretches over the securing post and engages in the undercut. This connector forn is simple and 25 intuitive, but other connector forms may be provided, for exampic, each side arm 511 could he provided with a portion (for example a male or female par!) of a Clip. As best. ilklitrated in Figure 7A, the side atm 511 diverge from the ctside wall of the seal, for example at an angle 713 of between 36, and 800, A strap secured to post 513 leaves the side arm in a manner as illustrated by IIne 715 in Figure 7A, at a location spaced apart from tihe seal, and 3 spaced apart from the face of the wearer. This is illustrated by the relative locations of the dp 717 of the side arm 511 compared with the centre line 719 of the interface. The distance 721 from the centre line to the tip of the side arm is preferably between 25mm and 50nn, and most preferably about 45mm. This compares with the distance 723 between the centre line 719 and the central axis of the nasal locator, which is preferably between 5ma and 10mm, and most preferably about 7rnr 35 It also compares with the approximate location of the inner wail surface of Ile ide portion of the 39 seal, where it leaves the central portion of the seal This location is ilustrated by broken line 725 in Figure 7A. Preferably this separation 727 is between 10rm and 20mm, and mosst preferably about 15mm. For further comparison, the outer most extent of the side portion is illustrated by broken line 729. The displacement 731 of broken line 729 from centre line 719 is preferably between 5 13mm and 30mm, and most preferably about 25mm In the front to back direction, the tips 717 are preferably rearward of the base of the nasal locators, so that bases of the nasal locators are between the central portion of thie mask hody and a li ne connecting the tips 7 1 7. With further reference to Figure 7A, overall, the mask seal may have a broadest exterior 10 extent 741 of between 30mm and 60mm and most preferably about 50mm. The seal and mask frame may have an overaE depth 743, preferably between 40Dmm and 65mm and most preferably about 55mm. Within this depth, the intenor space defined by the seal, which wraps around the nose of the user In use, may have a depth 745 that is preferably between 20mm and 40mm and moss preferably about 30mm 15 As can be seen from Figure 7A, in overall form, the seal curves through a significanL arc such that the side porons -are generally parallel with each other and opposed across the space that will accommodate the nose. The orientation planes of the side portions may form together an angle of between 0' and 45' and preferably between 0" and 25'. Preferably this applies to both the inner wall, and the outer wall, as illustrated in Figur 9A and 9B. Preferably this is also true for 20 substantially all of the vertically displaced levels within the seal, as illustrated by the different levels shown in Figures 9.A and 9B. The overall plan form of the seal, as illustrated in Figure 7A, could be considered parabolic, half elliptical, half oval or U -shaped. Viewed generally, the central pordon of the seal defines the width of the seal, with the side portions of the seal extending away from the Lateral ends of the 25 central portion in a direction substantially parallel with each other and substantially perpendicular to tis width dimension. Figures 53 and 5C also show die connection of the swivel elbow 313 to the mask body 303. The swivel clbow 313 includes a all portion 5.15 and opening 517. The outer surface of ball portion 515 is preferably a fostospherical surface, but could be formed with variation and still 30 achieve a substantial seal with socket 503. Similarly, the socket 503 is preferably a frustospherical surface with a slight intruding lip. This is best illustrated in Figure 3, where lip 803 intrudes slightly relative to the remainder frustopherical surface 805. The swivel elbow 313 preferably defines an angle beRveen flow in the conduit, and flow through the connection to the mask of between 0" and 90, preferably between 30' and 60 and 35 nmos preferably about 45' The elbow may incororate apertures 519 fonring part or all oh gas -40 washout vent for th.e patient interface. The apertures are preferably located on the outside of the bend of the elbow, substantially in the line of the flow path of gascs leaving the mask. Figures 5. and 5C also illustrate the connector portions 321 of the strap, cngarged ovc: posts 513 of the mask body. 5 Figures 7A to 7D give context for cross sections illustrated in Figures 8, 7D, 9A and 9B Figure 7D is a cross section through line EE of the seal of Figure 7C. Figure 7D illu.states the thickmesses of portions of the seal in the vertical centre plane of the scat This shows a thickening of the seal in the region 731 immediately adjacent and between the nostril locators. The cross secton also illustrates a thickening of the seal in the outer wall portion 431 of the central 10 portion of the seal above the outlet 403 and thickening of the outer wall portion 441of the central portion below the opening 403. These thickened sections are preferably gradually thickening from the thin supple perimeter portions 435 and 445 respectively to a sickness of approxinaely 2mm to 4mm. The supple wall portions, being the pe-ipheral portions 435 and 445 and the lower inside wall portion 443 and upper inside wall portion 433 preferably have a wall thickness between 15 0.05nun and 0-5mm and most preferably between 0.1imm and 0.2mm. The portion 731 between the nasal locators preferably has a thickness between 2mm and 0r5nn and preferably betw een 0.8nmn and 1mm. These dimensions are given relevant to a silicone material having a Shore A hardness of about 40. If the seal is formed of other materials commen-esutate alterations of dimensirn may be 20 possible while retaining suppleness of the envelope in the regions preferred supple and retaining sufficient stiffness to provide fcmnn to the envelope in regions intended to provide shape. Figure 8 is a section through DD of the mask seal and body of Figure 7A. This illustrates the cross section of the central portion of the seal at the outward side as illustrated and described already in reference to Figure 71, btr illustrates the connection of the seal opening to the opening 25 of the mask body. Flowever, the section of Figure 8 also illustrates a preferred cross-section-al form of a nasal locator. In particular, the thickness of tIe material of the wall 807 of the nasal locator is preferably between 0.5-rmm and 2mm and most preferably between 0C8mm and la-1m. The nasal locator includes a basc portion B09 and a nozzle portion 811 with a central opening 813. The portion including opening 813 fits inside the nostril of the user. The base 30 portion 809 provides prnary location at the entrance to the nostril. Figure 9A is a section itougli line GG of Figure 7D of the seal. This is a cross section of the scal approximately on the horizontal centre plane passing through the nosril locators. This section shows that the wall portions 807 of the nostril locators, the immediately adjacent region 921 outside the perimeter of the nostril locators, and the centre portion 731 between the nostril 35 locators all having a thickened wall relative to the supple wall portions 415 and 423 of tie side -41 portions of the seal In patticur, the regions immediately -adjacent and including the nasal locators preferably have a thickness between 0E5mm and 2mm and most preferably between 0.8mm and The outer wall portions 413 of tie side pordons of the scal are substantially thicker again 5 than the portions adjacent the nostril locators. These portions preferably have a thickness between 2mn and 5mm and most preferably between 3nm and Smu, These portions gradually tapel in tiickness to reach the supple thickness where they become the peripheral portion 423. The thickened portion of the outer side wall 413 of the side portions preferably extends to within 10nun of the outer most tip of the side portion. 10 The thickening and stiffness of these outer side portions 413 provides substantial form to the seal and stabi ty with the sep 1 in place- The side wail resists outward flexing of the side portions of dhe seal when the seal is inflated under pressure from the supply while the waE notions 413 will flex outwardly under pressure and have sufficient reaction force to retain the seal wrapped around the nose of the wearer. 15 The stiffemng produced by thicker regions of the seal could be provided by a composite material, or combination of parts. For example, the stiffness could be provided by reinforcement in the silicone, or by , flexible insect of stiff aerial. The insert of stff material could be integrated to the mask body. Preferably, the construction is such that the side portions of the seal provide resistance to flexing with an effective stiffness of at least IN force at the end of the 20 stiffened region to flex the side portion through an angle of about 60" Figure 9B illustrates a further, substantially horizontal plane, above the cross section of Figure 9A. This cross section is taken through line FF of Figure 7D. This again illustrates ie thickness of the outer side wall portions 413 of the side portions of the seal relative to the inner side wall portions 115 and perimeter portions 423 and relative to the thickness of the upper 25 internal wall portdon 433. Again, the side portions 413 preferably have a thickness between 2mm and 5mm, most preferably between 5mm and 3mm. The supple portions 415, 423 and 433 have thickness between 0.05mm and 0.5nmn, and most nrefcrably between 0.1mm and 02mm. Figures 10A to 10C are perspective views illustrating a patient interface incorporating a 30 number of inventions described in this specifiction. Figure 10 A is a front view, Figure 10B is a profile view, and Figure 10C is a back view. The interface 1000 is similar to the interface described with reference to Figures 3.A to 3C. The seal 1010 includes many simiaities to the seal of Figure 4. The frame assembly 1008 has some of the same features as the frame 303 of Figure 5. Like the interface of Figures 3A to 3C the 35 interface 1000 has a short depending conduit coupled to the Fame assembly 1008 by a ball joint or 42 swivel connection. Also like the interface of Figures 3A to 3C, the interface is preferably secured to the head of the wearer by a stigie loop strap. This loop strap may be made of materials described later in this specincation. The frame assembly may include lip stabilisers as described with reference to Figures 58 to 61. 5 Referring to Figures IA to 10C, the interface 1000 has an overall configuration including a frame assembly 1008 and a seal 1010 on the inside of the frameasmbly. A supply conduit 1004 depends from the frame assembly and supplies gases to the frane assembly, and thence to the seal. Headgear 1002 connects to the frame assembly to secure the interface to the head of a user. The frame assembly includes side portiuns 1016. Like the assembly of Figure 5 the side 10 portions may extenil away fromn the outside wall of the seal (and therefore away from he face of the wearer when ia use). At least one, and preferably both, side portion 1016 provides for connection of a connector 1014 of headgear 1002. The connector 1014 is connected to terminate an end of the strap 1012. Preferably each end of the strap 1012 includes a connector, and each side pordon 1016 includes a snatching 15 cooperating connection. The supply preferably includes a short flexible tube 1026, a supply connector 1022 and an interface connector 1006. Tube 1026 moy take many forms. For example the tube 1026 may be a stretchy conduit, a springy conduit that is usually short in the relaxed condition, an extruded corrigated tube or a 20 wound tape tube with a spiral rib. The tube sh.Ould be rcsistaiL to crushing and allow extensive lateral turning and beuding. The Ube Is preferably between 50mm and 150mm long. The interface connector may include a bias flew rent. However in the illustrated interface no bias flow vent is provided on the connector. The connector 1006 preferably incluacs portions of a swivelling joint 1020 to the frame assembly 1008. The connector preferably includes a portion 25 of a ball joint or swivel joint, and most preferably includes an extending follow plug portion which extends into a socket of the frame assembly. With reference to Figucre 1OB the connector preferably turns the supply flow through an angle between 25 degrees and 75 degrees. Most preferably the connector nts-ti the flow through an angle between 40 degrees and 60 degrees. 'Tis angle combines with the angle of the front face 30 of the frame assembly in the immediate periphery of the joint 1020 ([or example relative to die coronal plane of te wearer) so that the tube 1026 hangs easily below the interface (when the user is upright), remains close to the user when the user is lying down, keeps the joint 1020 close to the patient. 1he Supply connector 1022 preferably includes a swivel.

- 43 The frame assembly 1008 preferably includes a bias flow vent 1018. Bias flow vent 1018 iay include at least flow path from dhe interior of the interface to ambient surroundings. Au interface may be provided for use with a return flow type ventilator not including any bias flow vent. 5 Where a bias flow vent is included, the bias flow vent may include at least one aperture extending through the wall defining the frame assembly. In the illustrated interface thc bias flow vent :1018.includes a plurality of apertures. The apertures are arranged to direct the oudet flow of gases predominantly upward relative to the head of the wearer. By predominantly upward we mean that the gace re directed in a direction that is more parallel to the plane of the face (or the 10 coronal planc) than perpendicular to the plane of the face, and generally in the direction toward the forehe ad. As best seen in Figure i0, the fre a lay iclude depending support portions 1024 which extnid below the sedl 1(10. The depending support portions include pads 1030 which are intended to provide support onto the uppex Ip region of the weare, in the vicinity of the 15 nasolabial folds. On some users, thc pads 1030 may extend onto the lower cheek region imnediately adIjaceni the nasolabia] folds. The pads are intended to contact the face only when required to support the seal. This aspect of the interfacee is covered in more detail wish reference to Figures 18 to 61. Also in Figure 10C, the sea! can be seen to include a pair of nasal locators 1036. TEach nasal 20 locator mchides an opening, which in use is disposed within a nostril of the wearer. The nasal locators extend from a supple inner wall portion 1042 of the seal. In the illust-ated interface each nasal Iocaror includes a genetall' tubular nuzle portion 1040 :rncd a convex base portion 1038. The generally thuhibar norale portion 1040 may be somewhat tapered toward the onen end. The convex base portion may be considered a dome 25 shane. Both the nozzle portion and the base portions of each locator ate preferably oval or ellirincal in cross section. This is illustrated in more detail in Figures 1 I E to I 11H. Figures 1 1A to 1 1H are views of the soft seal component of the inMerface of Figures 10A to 10C. Figure 1' A is a top view. Figure 11B is a front view. Figure 11 is a rear view taken from a 30 position directly facing the open end of a nasal locator. Figure lID is a cross section through section CC in Figure 11 C. From these figures mainy sitmilarides can be seen to the seal of Figure 4. The utiLyi and function of the similar features will not be repeared in detail. In general terms the seal includes in inward facing wall portion and an outward facing w all 35 portion. The imner facing wall portion forms the seai against the face surfaces of the wearer. The - 44 outer facing wall portion connects the seal to the frane assembly and supports the overall shape of the seal. Like the seal of Figure 4, the general shape of the seal is a U-shape of V-shape, with side portions extending rearward from a central transverse portion. The outward facing portion Icludes ide portions 1032, which air of greater cross sLetion 5 than the inward facing wall The inward fiing wall includes nasal locators supported on a generally supple background 1052. A supple periphery 1034, 1044 connects the outward facing wall to the inward facing wal around the perimeter. With particular reference to Figure 1lA, and to Figtue 11D, each nasal locator preferably comprises a tubular portion 1042 and a dome portion 1038.Furhermore each tubular portion 10 tenrninates in a rim 1042 defining opening 1050L The tubular portion tapers toward the opening 1050. The taper is preferably a liner taper, but may altermatively be a curved tape. The surfaces of the dome portion and the tubular portion neet at an included, obtuse angle, for example between 120 degrees and 160 degrees. The cross-section of Figure LD suggests that the tubular portion 1042 is approximately 15 frsto conical, ard the dome portion 1038 s approximately frusto spherical. However in ea.ch case the alternate cross section (FigWes 11F to 11-) is oval rather than circular. Accordingly the foro of the dome is better regarded as elipsoid. The form of the tubular portion is better regarded as an elliptic cone. However in each case the shape need nor be a true ellipse, and may instead comprise less regular oval shapes, such Lisat dte forms night be regarded an ovaloid or ovaloid dorne, an 20 avoid or ovaloid cone or a tapering ovoid or ovaloid rube. The tubular portions of the nasal locators are spaced apart, but aligned such that their -axes are generally convcrgent. Preferably the convergent distance is between 10mm and 40mm front rhe openings of the nasal locators. The dome portions of the nasal locators come close together, about or adjoin at a cleft 25 1046 at the centreline of the seal. Preferably the cleft 1046 io fonned to allow soi freedom or movement of the dome of one nasal locator relauve to the dome of the other nasal locator. With particular reference to Figures 11- to I11H-, the oval cross second of each nasal locator is shown in more detail. In particular three cross sections of the nasal locator are shown. These cross-sections are taken on planes parallel to the plane of the opening of -the open end of the 30 nasal locator. What can be seen from these cross sections is the oval form. in particular the oval or ellipse of the opening 1050 has an aspect ratio of approximately 1.8 to 1, The major axis of the oral or ellipse is greater than twice the minor axis, and preferably between 1.5 and 3 tirnes the minor aXis.

- 45 The oval form is retained trnoughour the tubular portion and the dome portions of the nasal locator. However, in the illustrate seal the absolute difference in the major and minor axes is retained, rasher than the ratio, Therefore the ratio reduces moving from the shape on opening 1050, to the frst cross section 1054 spaced toward the base of the tubular portion. The ratio 5 further reduces moving from cross section 1054 to cross section 1056 at an intermediate position on. the domc portion. The ratio further rcduccs moving from c-oss section 1056 to cross section 1058 at the base of the dome portion. 1 Bv way of example, for the tip opening the major axis dimension may be about 9rn and the minor axis about 5mm For the cross section of the tubular portion at EE, the major axis 10 dimension mar be about 13mm and the minor axis dimension about 9mm. For the dome portion at GG, the major axis dimension ray be abour 18imm and the minor axis dimension about r5mm. For the dome portion at HH, the major axis dimension may be about 22mm and the ninor axis dimeIoo about 1 snmm, 15 A s is best illustrated in figure I0C, the oval forms of the nasal locators -are preferably riot ahgned parallel when viewed from the back of the interface in particular the upper ends of the ovals are closer than the lower ends. When projected posteriorly onto a coronal plane of a hypOthe tical water t rajOr Axes of the ovals fot-rn an angle of between 60 and 120 degrees. Each nasal locator is preferably provided with a lip 1042 at the open end 1050. The 20 matenal at the lip 1042 is preferably thicker than the material of the rest of the tubular portion, or of the material of the region of tie tubular portion in the near vicinity of the lip. The thickened lip provides some positive form to the end of the locator when locating the locator in the nostril of the wearer. This may be use ful for the wearcr to better feel the end of the locator when fitting the interface. 25 Figures I1B and 11E also illustrate features of the seal involved in securing the seal to the trame assembly. As seen in Fiure 11 B, the outward facing portioi of the seal includes a major opening for securng with the frame assembly. The major opening includes a hp 1W-8 that nuas trne perimeter of the opening. The lip may be constituted by the thicker regis of the outward'wall of the seal. For example the lower portion of the lip is illustrated in cross section in Figure 1 L. 30 At a location, or multiple locations, on the lip, markers or features may be provided to ensure the correct assembly of the seal relative to he Frame assembly. The seal illustrated and described is sensitive to incorrect assembly. In this embodiment the seal is arranged to be detachable from the frame. For easier positioning, the lip is preferably provided with a protrusion, which engages in a 35 notch of the frame when the seal is in the correct position. The lip may be provided with a - 46 protrusion 10 4 6 extending in either or both of the ioward and outward direction In the illustrated embodiment two protrusions 1046 are provided, which engage with notches 1074 and 1092 of die ftre, The lip of the seal takes the overall forn of a bent ovaL By this we irnean an. oval that has 5 been bent so that the ends of the oval are curved away from a plane tangential to the central portions of the oval. This can be seen in a general sense in the forn of the outward wall portion of the seal, in Figure 11 A. Figures 12A to 12H are views of a frame asserably of the interface of Figures 10A to 10C. Figure 12A is a fEont perspective view of the &ame assembly. Figure 12B is a roar perspccive view 10 of the frame assembly. Figure 12C is a side profile of the frame asscrably. Figure 12D is an assembly view of two components of the frame assembly. FIgure 12EP is a back view of the frame assembly. Figure 121 is a back view of a frame assembly that Is of a slightly configuration, and with the stabiliser portions not showing. This illustrates an alternative configuration of ie 15 channel for securing the seal The frame assembly may otherwise be formed and assembled iT substantialy the same manner as the frame assembly of Figures 12A to 12H. The fare assembly 1008 comprises two major components, a first component 1070 and a cover 1060. The two components of the frame assembly combine to provide a channel 1096 for 20 securing the lip 1048 of the seaL The first component 1070 my include a first portion of the channel, while the cover 1060 provides a second portion of the channel. The component 1070 may provide an inside flange portion 1072, and the cover provide an outside flange portion 1094. A base portion for the channel may be provided extending from the flange portion of either par. For example the base 25 portion 1088 may be provided from the flange portion 1072. 'The flange portion 1072 may include a noEch 1074 for receiving a locating feature of the lip 104N8 of the seal. The flange potion 1094 may i include a notch 1092 for receiving an additional locating feature of the lip of the seal. According to the preferred form of the seal and channel the channel has a general outward 30 flare, so that portions of the channel on opposite sides of the main opening diverge relative to each other when progressing from the base of the channel to the open edge of the channel. Accordingly the lip of the seal stretches to pass over the inner flange portion 1072 and the seal is retained in the channel by the elastic tension of the lip. In the frame assembly of Figures 12A to 121-, the channel forms a general bent ellipse. In 35 ie example of Figure 121, the channel follows a path more alike to a bent rounded oblong or 47 trapezoid. in particular, the overall path of the channel is not as broad as the path of the channel in the enboduiment of Figures 12A to 121. Futtisermore, the channel includes comparatively straight side portions 1220. The side portions 1220 converge slightly extending toward the lower portion 1226 and diverge slightly extending toward die upper portion 1217. While this assembly 5 retains the overall bent oval shape, the straightened side pardons are found to improve ease of assembly in comparison with the sharply curved end portions of the bent ellipse of Figures 1 2A to 121-. The notch and protrusion alignment is preferably provided adjacent the upper or lower portion of the channel, most preferably adjacent the upper portion of the channel. Thus the lip 10 1048 can be seated in the channel with the correct location, and the rest of the lip then stretched over the inner flange porontiy 1072. The first component 1070 may include extensions to carry support pads 1030. For example a lower shield portion may extend in a curve below the supply opening of the interface. The lower shield portion may include side portions. Pads 1030 are provided on die lower inside 15 surface of the side portions. An intemal surface 1078 of an upper portion of the shield may wrap around to the sides of the interface and be located outside and adjacent the outward wail of the seal. The upper portions of the shield can assist in retaining the form of the seal under internal gases pressures, by constraining outward deflection of the outside of the seal envelope. 20 The first component may carry a portion of the swivel connection 1020. Preferably the first component 1070 includes a ring portion 1080. open to the front and the back. The ring portion preferably includes surfaces to engage with surfaces of the supply tube connector. Preferably the ring portion 1080 includes an inwardly facmg substantially spherical surface 1084. The inwardly facing surface 1084 may engage an ouvardly facing complimcntary surface of 25 a ball portion of ric upply tube connector. The ball portion of the supply rube connector may have in internal passage leading gases from the supply titbe through the :ing portion 1080. One advantage of this arrangement is improved available material choices. The supply tube connector is preferably made from a different base polymer material to the ring portion 1080 of the component i 1070- Different polymer materials working against one another tend to exhibit 30 lower friction and noise than polymers of the same base material. Yet the outside cover 1060 can be fori-ned. from the same marTial as the supply mbe connector, and thius present an aesthetically pleasing exterior. For example the ning portion of component 1070 may be formed from a material chosen from. its strength and toughness, such as a polycarbonate plastic, and the cover 1060 and supply 35 tube connector fdnncd from a plastic chosen paimardy fox surface finished and appearance such as - 48 an acetal plasdc' The acetal plastic may mclude a lubricating copolymer such as PTFE (poiytetraflutoethylene). The rang potion 1080 may also providefcatures for securing thc two coinponnasts 1060 and 1070. 5 For example the outer surface of ring portion 1080 may b provided with outvwrdlV facing features such as depressions, or a channel 1082, to cooperate with inwardly facing clips or an inwardly facing annular ridge 1087 of the perIiCer 1066 of opening 1068 of cover 1060. This is best illustrated in the cross section in Figure 12G. The outer periphery of the cover 1060 may blend into the surfaces of the component 1070 10 in some parts. For example the lower curved edge of the cover 1060 may abut the upper curved edge of the lower shield of the component 1070. ihis is indicated at 1081 in Figure 12G. A similar abutting edge at the side pti on s indicated aL 08 1i ln Figure 12H. The components 1060 and 1070 may form an outlet plenum adjacent the bias flow vent 1018. This is best understood by considering the exploded view Figure 12D and the rear view of 15 Figure 121 ad the cross sections of gurures 12G and 12H. The plenum 1079 is defined between a aet oval frame pordon 1072, of component 1 (P0, and the inside surface of the cover 1060 in the vicinity of apierture 1068. Openings 1086 into the plenum 1079 arc defined by the rear edge of the ring portion 1080 and by rhe oval rame portion 1073. Ga sea flowing From the seal to the bias flow vent pass 20 Ihrougth these openings. The inside surface 1098 of the Fange 1072 of oval frame 1073 preferably converges moving toward the pleum, defining a flow irecting surface acting like a fUnnel. The holes of the hias fow vent 1018 lead from lhe plenum 1079. The ring portion 1080 opens essentially centrally through the ova frame portion 1073. This divides the flow into the seal and the flow out of the seal essenilly at a location directly 25 adjacent the open end of the seaL The ring portion mray be supported in tins position by one; r more supparing struts 1076, or by regions at the top and bottom where the ring snd oval frame portion come togeder. I he bias Low holes 1097 are arranged in a curve around the upper portion 1089 of the plenuin chamber 1079. This upper portion -, qute confined in the location iflustrated in Figure 30 12G, immediately above the ring portion 1080, but more open to either side. To provide an upward exit flow (generally parallel to the corona planc of the wcarc), the bias flow holes may be arranged in a shelf portion 1099 of the wall of tie cover 1060. The lower shield porrion oF rhe component 1060 may include a soft covering 1085, such as an ovemnoulded layer of a soft biocompatible material, over a more rigid skeleton or frame 1083. 35 A preferred covering would be, for example, a thermoplastic elastomer, a polyurethane foam, or a - 49 silcone elastomer. The skeleton or frame 1083 of comnonent 1060 may be formed from a cop olymer including an amount of a plastic material that bonds strongly with the covering materiaL For example, the frame 1083 may be fonned from a polycarbonate siloxane copolymer. Tie siloxane contributes chemical resistance and improves the bonding of the overmoulded silicone 5 co-ver. Extreme side pordons 1016 of the cover 1060 diverge from the outer surfaces of the shield of component 1070. The side portions 1016 end in sockets 1062 for receiving connectors of the headgear strap. Figures 13 to 20 show a further embodiment of an interface with wrpn around inflating 10 seal. Th Cnt-face. I 100 includes a seal body 1 101 and tra re 1102. Attached to the frame 1102. is tubing 1112 that is attached to a gases supply apparatus. The tubing supplies gases to the mask frame and seal. The tubing 1112 may be tethered to tie user (wearing the in erface 1100) by a l 1113. In use the lanyard 1113 extends about the users neck The Lanyard 1113 is affixed to the tube by known methods, however, shown is a c-shaped 15 clip 1114 attached to the lanyard 1113 that clips abour the tubing. The interface 1100 is held in place over the user's nose by way of a head strap 1114. The strap is preferably made of a flexible type material, such as silicone or a laminated material well known in the art of head gear straps. Each end of the strap 1114 is preferably fated to a clip 1116 that attaches to a corresponding eyelet 1.117 fonned in or attached to the seal body 1101, The 20 strap may be a f.r rmoulded silicone strap, a small hollow silicone tube, or appropriate configurations as are known in the art. The flame 1102 mniay have formed in it a pluralir.y of bias flow holes 1115 to allow for exhausting of die users exhalated gases from the interface. Alternatively, bias flow holes may be formed in the seat body 1101 to allow for exhausting of gases, 25 The seal body 1101 ics agan a supple or inflatable type seal. The seal body 1101 is curved in shape to match the contours of a hurnau face and exteuds 'about the user's ne, wtappinag the user's nose.. The seal body 1101 preferably extends completely over the side of the user.s nose and may also extend parialy over the user's cheeks. The seal 1101 comprises an inner wall with an inner 1103 and an exterior wall with an outer surface 1104. Projecting from the inner surface 1103 30 arc nasal locators 1105, 1106, each with outlets 1107, 1108. As with the embodiment of Figures 10 to 12 the seal body 1101 includes an irer opening 1109 that is opposite the nasallocators 1105,1106 and receives the frame 1102. The seal 1101 has a variable wall thickness such.S that there is rigidity around the portions of the seal that project out, and flexibility between tie nasal locators 1105, 1106 and a enphery 1110 35 of the inler opening 1109 of the seal This means there is a decoupling effect between the nasal -50 locators 1105, 1106 and the inlet periphery 1110, and subsequently to the mask frame 1102. This will mean that some movement of the mask frame will be possible without disrupting die sealing of die nasal locators 1105, 1306 on or in the user's nostril. As can be seen in Figure 18 the inlet penphery 1110, which defines the gases inlet 1105 to 5 the seal, has a substantially thick cross-section. This provides rigidity to the ileCt periphery 1110. Similarly, the nasal locators 1105, 1106 have a substantially thick cross-section. However, the thickness of the nasal locators may not necessarily be as thick as or ticket than the ilet periphery 1110. In the preferred form the thickness of the nasal locators is less than that of the milet periphery.. 10 The areas between the inlet periphery 1110 and the nasal locators 1105, 1106 is preferably thinner in cross-section than both nasal locations and the inlet periphery. For example, in Figure 1S the length of the seal 1101 between X and Y is formed to be substantially thinner in cross section than either the inlet periphery or the nasal locators. This means this length is more flexible, effectively allowing more movement of the nasal locators 1105, 1106. Furthermore, as the length 15 between X and Y, including an outer periphery 1111, is thinner in cross section the seal will easily inflate to assist in rte sealing of the seal about the user's nose. As shown in Figure 18, preferably a region 1 18 of the envelope adjacent to the base or toot of each nasal locaEto has a thickened cross section. As shown, preferable the length or region 1119 of the seal between region 1118 and the thikcncd inlet periphery 1110 is formed to be 20 sabstantially thinner in cross-section Chin either the inlet periphery 1110, the nasal locators 1105, 1106 or region 11.18 In an alternative enibodiment, the envelope includes a thickened region 1118 adjacemL the root of the nasal locators and the thickness of the cross section of the nasal locators is not Chickerned. For example, the thickness of the cross section of the nasal locators may be similar to 25 the thickness of the envelope region 1119 extending between the regions 1118 adjacent the nasal locators and the inlet periphery 1110. The thickened region I 118 adjacent the root of the nasal locators prevents the base of the nasal locators from defor or ballooning excessively under typical CIPAP pressure. However, the thinner wall of the nasal locators 1105, 1106 in this enbodiment tay balloon undet CPA P pressuore-. 30 Preferably the seal 1101 is formed front silicone with a Shore A hardness of about 40. Altematively other materials with siniilar properties may be used. For silicone with a Shore A hardness of 40, or other material with similar properties, the thickness of die envelop region 1119 extending between the nasal locators and the iniet periphery is less than approximately 0.5mm. Preferably this region 1119 has a thickness of 0,1mm to 0.2mm. Alternatively this region 1119 of 35 the en-vclope may have a slickness of less dian 0,1mm, for example 0.05rnr.

- 51 The thiclmess of the region 1118 adjacent the base of the nasal locators preferably has a thickness of less than 2mm. Preferably the thickness of the region 111 S adjacent the base of the nasal locators is approximately 0.8mm to 1.0mm. Alternatively the thickness of the region 1118 adjacent the base of the nasal locators msay be less than 0.8mm, for example 0,5mm 5 'The thickness of te region adjacent the inlet periphery is approximately 3mm to 5mn, bt could be thinner, for example 2rmm, The nasal locators have a thickness of less thtan 2nn. In the preferred embodiment, the nasal locators have a thickness of approximately 0.8mm to I .0mm. Alernatively the thickness of the nasal locators may be less than 0.8mm, for example .5numn. 10 In the alternative embodiment desenbed above, the thickness of the nasal locators is similar to the thickness of the envelope region 1119 extending between the nasal locators and the ilet periphery. In this embodnent, the nasal locators have a preferred thickness of approxirm.ately O mm to 0.2mm. Alternatively the thickness of the nasal locators may be less than 0.

2 mm, for example n005nm. 15 Preferably the change in thickness from one region of the seal to another occurs gradually. For example, the thickness of the seal changes gradually from thickened portion 1118 to thinner portion 1119. Similarly, the thickness of the seal changes gradually front thickened portion 1110 to thinner portion 1119. Referring now to Figure 20, which shows the seal 1101. in cross section through AA of 20 Figure 16. This figure shows an alernative view of the seal 1101 showing the varying thicknesses of parts of the seai. In particuhr, the inler periphery 1110 and nasal locators 1106, 1108 are thick in cross-secieon compared to the outer periphery 1111. At least i the lateral direction, the thickened region 1110 adjacent the inlet extends for at least half of the distance from the inlet to the outer peripheral edge 1121. In the upward direction the thickened region extends at least half 25 the distance from the inlet to the top peripheral edge 1123. In the downward direction the thickened region extends at least half the distance to a lower face portion 1125. The areas of the seal between the nasal locators 1106, 1107, generally indicated as 1112, are also thicker in cross section to provide additional stability in these areas for the nassi local tors. In Figure 21 an alternative embodiment of the scal is shown. In this alternative 30 eimbodirient the areas between the nasal locators, indicated as 1113, arc substantially thinner in cross-section than that of the inlet periphery 1110 and nasal locators 1106, 1108. This configurati r would provide additional flexibility between the nasal locators 1106, 1108, A yet further embodiment of a seal of de present invention is shown in Figure 22. Here the seal is an inflatable type, but the seal extends down to occlude the user's Inouth in use. This 35 seal 1200 has nasal locators 1201, 1202 and is received in a frame similar to tha: described in any of the embodiments detailed above- The seal 1200 has an extension 1203 that goes over the user's month creating a seal and reducing mouth leaks, Another embodinent of a seal of the present invention is shown in Figure 23. This seal 1300 is of the same form as that in Figure 22, with nasal locators 1301, 1302 and a mouth covering 5 extension 1203, but includes an outlet 1304 directed to the user's mouth, allowing for gases to be delivered simultaneously to the user's mouth as well as the user's nasali passages though the nasal locators 1301, 1302. Figures 24 to 29 show various head straps that might be used with any of the embodiments or the interfaces described herein. 10 Figuie 24 shows a single head strap 1402 attached to the inrerface 1400, particularly to the flexible and inflatable seal 1401 by any appropriate means as Inown in the art of interfaces and head straps. The strap 1402 may be a hollow tube 1402 as shown in Figure 24a or a solid tube 1402' as shown in Figure 24b. The hollow tube could, for example, be an extended silicone. tube, with a diameter between 3mm and 6mm and a wall Thickness of 0.2mm to 1mm. 15 Figure 25 shows a single head strap 1410 attached to the interface 1400, particularly to the flexible and inflatable seal 1401 by any appropriate means as known in the art of interfaces and head snaps. The strap 1410 may be a hollow elongated tribe 1410 as sbowr in Figure 25a or a solid elongated tube 1410' as shown in Figure 25h. The strap is preferably thinner in width at its endsh 1411, 1412 that attach to the seal 1401 and thicker in width at its midpoint that sits at the 20 back of. the user's bead in use. Figure 26 shows a double head scrap 1420 attached to the interface 1400. The soap 1420 extends about the users ears and has two attachment points on each side of the scal 1401 where the strap attaches to the seal 1401. Figures 27 and 27a show an extendible head strap 1430 attached to the interface 1400. The 25 strap 1430 has an arca 1431 that can be extended and contracted to better fit the strap to the users heae. Figure 2S shows an alternative head strap 1440 attached to the interface 1400, particularly to the seal 140. The head strap 1440 preferably includes side straps 1441 having areas of rigidity 1442, 144-3. to provide additional stability to tie side straps 1441. The head strap 1440 also 30 preferably includes a top strap 1444 -and a back strap 1445 thar each extends over the head or behind the head respectively. This head strap is detailed further ta1 US Patent Application No. 12/307993 of Fisher and Paykel Healthcare, the contents of which are incorporated herein by reerence.

Figures 29 and 29a shows yet a further alternative head srap 1450 attached to the interface 1400, particularly to the seal 1401. The head strap 1450 is curved and has partitions 1451 that provide additional sUpport or rigidity to the strap. The head straps detailed above may he formed of any appropriate. material, such as, flexible 5 plastics, silicone, laminated fabrics, or other appropriate materials. Figures 30 to 33 show various ways in which an interface frame may be attached to an inflatable scal body, In Figure 30 the seal body 1500 includes overmoulded or bonded rigid plastic barbs 1 502. The barbs 1502 clip rito correspondingly shaped recesses -13 formed in the frame 1501 end hold the seal body 1500 in sealing engagement with rhe frame 1501. 10 Similaldy: in Figure 31 the seal body 1500 has a periphety 1512 that is formed with a ove-mioulded or bonded rid pkstic looped clip 1513 that clips to the frame 1501. Further details of such a clipping nechatism are ceactibed in US Patent Application Number 12/502528 of Fisher and Paykel Healthcare, the contents of whidh are incorpora ted herein by reference. Alternatively, as shown in FiguLre 32 the seal body 1500 may have an inlti 1322 dIal has a 15 stretch interference fit about the frame 1501- The frame preferably has a groove 1523 arid raised edge 1524 that allows the inlet 1522 to engage with the frame. In a further alernative forn as shown in Figure 33, a scal body 1500 may be permanently attached to the frame 1501 by cvennoulding or bonding. Figures 34 to 40 illusate various ways in which the robing (1112, see Figure 13) extending 20 from the. interface 1100 i-may be secured to a user. The advantage of securing the tubing to the user is to Lake the weight of the tubing off the interface, reducing the possibility of the interface being pulled from the useX's face. i 1ac of the braces described below is preferably madc from fabric straps. It is preferred that the fabric is a breathable type material, but otier appropriate fabrics mar be used. In all forms detailed herein the tubing is fixed to the brace by way of a clip or pin. 25 In Figure 34 a brace 1600 is shown that is made from a looped strap of fabric that M use Is placed about the user's head and one shoulder. In Figure 35 an alternative brace 1610 is shown. This brace is also preferably made front fabric that is formed in a central cross across the users chest and is braced around each of the user's arms. 30 In Figure 36 a further alternative brace 1620 is shown. Here the brace 1620 has a central cross of straps across the user's chest, but it is hi-aced across the users neck and back. AlterniatvClv as shown in Figure 37, a brace 1630 could be used to secure tubing to the user where a brace is formed from the looped strap that is exTtnded about thbe user's chest and under their arms.

--54 As shown in Figures 38 or 39, a brace 1640 may addfiinally include two shoulder straps 161, 1642 or simply one shoulder strap 1643. Alternaively, as shown in Figure 40, a simple brace 1650 may be used with the ierface of t1he present invention that simply fits In use about the user's shoulder or upper arm. 5 Additional rube support armagemnts will be described with reference to Figures 41 to 57. Figures 41 to 51 describe a supporting collar intended to be worn around the neck of the user, and to which the tube may be supported by a tether, Figures 52 to 55 describe aspects of a tether that might be used with such a collar, or might be. used with other arrangements tot securing one end of the tether to the patient Figutes 56 ad 57 iiustrate two such arrsvigeetrnis for securing a tether 10 to the patient. Figures 34 to 40 illustrate other arangemens for scecunng such a tether to the patient. Figures 41 to 45 illustrate -in further detail the collar previosly described inl broad terms in relation to Figures 3A to 3C. The collar includes an adjustable connection 327 and a secondary connection 329. The adjustable connection operates between a first end of the collar 4100 and a 15 second end 4102. The adjusabie connection 327 allows the user o set the amount of overlap of the ends 4100 and 4102 to be set. Figures 41 to 45 illustrate an adjustable connection 327 in the form of a dome fstener system. Oine fastener portion 4104 is fixed to the first stra end 4100. A. number of complementary fastener portions 4106 are p-ovided spaced along the second strap end 4102 Engaging the fIstener 4104 with one ofb t series of stener portions 4106 sets the overap 20 of end 4100 relative to end 4102. The fastener portions 4106 may be spaced at intervals between 2cm and Scm, preferably between 3cmu to 4cm. This provides a degree of variation in the circumrference of the collar in increments of between 3cm 4cm. Preferably the outer ovetdapping end 4100 includes a singic connector portion and the innert strap end includes a series of outwardly-facing second connector portions. According to this 25 arrangement, no connector portion faces toward the atienL neck. Accordingly, the internal surface of tihe collar is free of distracnng projections. The connector portions may be portions of, for example, a dome fastener of known type. The extreme end of inner end 4102 may include an outwardly projecting loop engaging Over the overlapping portion of the collar strap. This loop 4302, shown only in Figure 43, would 30 align the free end of underlapping end 1102 with the overlapping portion of the collar when the collar is set on tighter sizes. Aherative connectors for the adjustable conrmerion are illustrated in Figures 46 to 49 The dome fastener connection is illustrated in more detail ins Figure 46. Arn alternative fastener using engaging magnets is illustrated in Figure 47 The outer strap 35 end 4702 includes an inwardly-facing magnet portion Z704. The inner strap end 4706 includes an outwardly facing magnet portion 4708, The inwardly-facing magnet pordon 4704 preferably is magnetized to 'a G(ist polarity facing inwards. The outwardly-facing magnet pation 4708 is preferably magnetized with a complementary polarity facing outwards- A striest ofotwardly facing magnets 4708 would be spaced along dhe outer surface of the inner strap portion 4706. 5 The magnet portions rmay be fixed to a base portion 4710 whici in turn mar be fixed to the strap. For example, the magnets may be glued to a substrate material that can be stitched to the strap. Alernatively, magnets might be moulded to include holes to allow the magnets to be directly stitched to the strap. The magnet 4704 could be replaced by a magnetic material which would be attracted by 10 magnets 4708 but not be a magnet itselE Alternatively, magnets 4708 could be replaced by portions Of a material rhat is rtiagnetic but not itself a magnet. By way of example, the magnets rmay be ferrite or rare earh, while magnet materials night b small sections of steel, Ferrite powder bonded with a flexible polymer ray allow the magnets to be flexible whe tnaintaimng sufficient stength to secure the collar. 15 Figure 18 lustrates thc adjustable connection being made by a hook and loop fastener system. For example, the outer en d portion 4802 may include a short section 4804 of a material with project ting hooks. The inner strap end 4806 may include an outwardly-facing section 4808 covered with loops, to which the hooks may engage and disengage. Suitable hooks and loop fastener naterial is sold under the Velcro brand. 20 The outwardly cing loop material may be stitched to the collar strap, or the collar strap may be formed from a material that integrally includes the loops. The length of the loop portion 4808 is much grearer than the length of the hook portion 4804 and preferably extends a length equivalent to the adjustment required to be available to the collar. For example, the loop fastener material would have. a length of about: 15cm along the collar strap. 25 Figure 49 illustrates an alkernarve mechanical fastener similar to the dome fastener. This type of dome fastener includes a smaller receiving aperure 4902 on the female portion and smaller projectng inns 4904 on the male portion. Referring back to Figures 43 to 45, the collar prefecably includes a second releasable connection 329 between a third end 4302 and a fourth end 4304- Thus, the overall ring of the 30 collar is divided into two separate strap sectons, Each scrap section includes at one end part of the adjustable connections 327 and at the other end part of the second connection 329. Preferably this second connection is not adjustable. This second connection 329 is inended to be engaged -and disengaged at each use of the collar. The a.djustable connection can he adjusted to the correct length and set, and the second connection 329 can be used to secute and 35 release the Collar -56 This second connection 329 may be forced by any suitable means, including the examples illustrated in Figures 46 to 49, or including a plain releAsable fastening clip such as illustrated in Figures 50A and 50B (50A in the connected condition and 50B in the open condition), or a breakaway connector which releases upon application of tension in a predetermned rage. 5C The connection 329 ilustrated in Figure 45 includes a breakaway connector having a first body pardon 4502 sccurcd to strap end 4302 and a second body portion 4504 securcd to fourth strap cnd 4304. TI-c iarst and second body portions each include a projecting tang and a socket, The projecting tang of one body is complementary with the socket of the other body. The projecting tang and socket preferably have an interference fit- The amount of interference and the 10 force required to pull the rang from the socket defines the release force for the breakaway clip. This preferred breakaway clip is illustrated in mote detail in Figures 51A and 51B. In Figure 51A, the clip is illustrated in the open configuration where a rang 5102 projects frorn each clip body portion and each tang 5202 includes a small lateral projection 5104. The socket in each body porton of Lhe clip includes a Lateral aperture 5106. When the rang 5102 is Pushed into the 15 socket the projection 5i04 extends into the aperture 5106. The interference fit is provided by engagement of the projection 5104 in the aperture 5106. This connector is shown in its engaged condition in Figure 5 LB. Referring again to Figures 41 to 45, a tether extends from the collar. The tether 4112 is connected with the collar at one end 'arid to an engautg clip 4114 at its &ee end. The engaging clip 20 4114 is for connection with the supply conduit for the patient interface. The engaging clip 4114 is illustrated in greater detail in Figure 55, where an enlarged view of its fitting with the cuff of the conduit is illstaatcd. The preferred coiiuector includes an open ring which fits over a. sleeve portion of the cuff and is held in place between a flange 5502 of the cuff and a flange 5504 of a swivel conduit connected to the cufE 25 The preferred tether includes a breakaway cia at some position along its length between the connection to the collar anc the conduit connector. The brieakaway connector may be of the form described already with reference to Figures 51A aad 5113. That form of breakaway connector is illustrated in Figures 52, 54A and 54-B. Alternaively, the bteakawai connector nav aho include a swivel, sLc tEhat the collar does 30 not need to be correctly oriented relative to the conduit before donning the patient interface. In this case, the breakaway connector may include a socket portion 5302 and a male poriioa 5301, with the nale portion 5304 being rotationally synimetric. For example, the male portion 5304 may include a projecting knob 3306 with an enlarged end 5308. The socket 5302 would include projecting portions or an annular projecting portion around the internal circumference adjacent the 35 open end. The socket 5302 may be required to be made in two pieces subsequently secured -57 together to produce this projecting lip or lips. The socket portion 5302 may be open at its other end 5310 so that the connector portion 5302 can be formed in one piece. This end tAry acconun date an end of a strap porton 5312 of the tether. Alternatively, a swivel may be included at another location along the tethet 5 Preferably the tether is fonned with a sliding cotnectar 5202 at one end for conlcctiol over the collar. The sliding connector 5202 preferably comprises a moulded loop including stzrught sections either side of the web of the collar and joined by transverse sections above and below the collar edge. The loop pre ferably has a moderarty aght fit on! the collar so thai once moved into a position, it ends to stay in that position but can be moved along the collar upon application of 10 sufficient force. The loop 5202 essentially mirrors the profile of die web of [he collar. A tedher portion may extend from the loop 5202, prefermbly being integrally formed with the loop 5202. Preferably the tether portion and loop are formed from a flexible resilient traterial such as silicone. Another rethet portion extetids from the Quick release connector to the conduit in engagement clip. Again, this may be formed of any suitable material, preferably flexible and 15 preferablI a silicone material. The tether may be of fixed or adjustable length. Preferably, the tether may be provided in multiple lengths, for selection by a patient. The tether may be of a length between 3cm and 15cm. A tether at approximately 3cm is iliastrared in Figures 54A to 54B, the tether including limited, if any, strap portions. This tether is mostly made by its loop connector to the collar, by the quick 20 release conectot and by its connection to the conduit cotinector. A longer tether is islustrated in Figure 52 and in Figure 53, including a sub:tantial strap portion between the connecting oop 5202 and the quick release connector and as other substantial strap poruon between edi quick release connector and the conduit connecur- These portions of thc tthcr could be interchanged, so that for example, the strap portion of the tether could be 25 provided entirely to one side or other of the breakaway connector. Figure 56 illustrates an alternative support arrangement to the use of a collar. The tether 5602 terminates in a dip 5604 instead of termiatmg at ;1 coector for the cor The clip .5604, preferably in the form of a type of peg, alligator clip or other arrangement having gripping jaws, is intended for attachment to the neckline or other convenient portion of clothing worn by the 30 patient. Altermative, the tether may be terminated at a connector for connecting to brace structures tu be worn by the patient as described earlier, The tether may or may not include a breakaway connector. Figure 57 illustrate another alternative for connection to clothing 5702 on tie patient This illustrates the push clip 5704 connected to the collar line of the clothing and including a 35 brealkaway connector 5706.

- 58 lThe referred collar is constructed frorn materials comrtable to the wearer. 1r: the simplest form, the collar might be, for example, a strap of a soft, flexible material having sufficient stiffness to hold the general collar form. sufficient strength to resist any substantial extension or stretching and comfortable inside surface facing the patient. One suitable material might be, for 5 example, a lainated foam material such as Breathoprene, which has a foans web, faced on either side with a kniued fabric. However, the preferred collar is more resistant to stretch than the Frcathuprenc material, and more breathable than the Breathoprene material. For comfort against the skin, the collr is preferably Faced with a woven, kitited or braided natural fibre fabric. For example, a braided or 10 knitted tube of cotton or bamboo yarn. To provide form to the collar, the braided or knitted tube surrounds a flexible skeleton, The flexible skeleton might comprise a series of hingedly connected frames, or a moulded flexible strap formed with an open framework. Preferably it cotmprises a narrow strap of plastic mesh. An example of suitable mesh is 3MESH, manufacture by Mullter Texti Group of Germany. The open faunework or mesh foun allows moisture and heat to pass 15 really through the collar, reducing discomfort of the patientwearing the collar for long periods. The collar strap is preferably 3cm to 6cm wide and between 3mm and Snimm thick. One preferred simple head strap is illustrated in Figures 3A to 3(., It includes a single, non bifurcated strap terminated with a connector at either end. The strap could be permanently connected to either end of b.e frame, but preferably the connectors are configured to be removable 20 from the body of the maslu Another example of a preferred headstrap is lustrated in Figure 10A to 10C, and a preferred connection clip is illustrated in Figures 63A to 63D. The single ron-bifurcatcd strap preterably acconrnodates a sus.Santial variation in head size without adjustment. The preferred strap has a very low stiffness with extension of a 400mm king strap from a fury laid out but unstretched condition to a condition 1.3 times its original length 25 requires a force not exceeding 4N, and preferably not exceeding 2N. Figure 62 is a graph ilhmstrating the force versus extension characteristics of four sample strap materials. Ihe preferred material comprises a knitted or braided ube nylon yar incorporating strands of Lycra. The nylon yarn is sufficiently loosely forced that is capable of extension beyond the range required without becoming tight. The arnount of Lvcra strands in the yarn may be varied to vary the stiffness of the 30 strap. An overall diameter or width of the strap is preferably less than 10mGrm and most preferably less dian 6mm. The end connectors of the strap may be fixed to rie strap in any suitable manner. Preferably the end connectors are overmuoulided to ends of the straps. Test results for a range of alternative strap materials are illustrated in Figure 62. AR test results are for extensions of a length 35 of the rested material fron an "at rest" length of about 400mm.

59 Line 6202 shows extension test results for a knitted yarn of nylon incorporating Lycra filaments, the knitted rube having a nominal diameter of Smtm. This also is stiffer than desirable. line 6206 illustrares a hypothetical most desirable response determined by the inventors, Line 6209 illustrates the response for an extended silcone hollow tube with a wall thickacss a of 0.25mm and at outside diameter of 3mm. Line 6207 illustrates the response for an extended silicone hollow tuibc with .i wail thickness of 0.25mm and an outside diameter of 6mm, Both these silicone extensions show satsfactoy characteristics. Line 6205 illustrates the response of the preferred fitted nylon yam incorporating Lycra 10 filaments. This knitted tube had a nominal diameter of Sin Line 6208 illustrates the response of a length of 3mm woven ctstic webbing. This product exhibired similar charaCteristics to the preferred knitted yarn, however the elastic webbingi has a tendency to catch hair and to lose elasticity. T"he most preferred headstrap comprises a braided stretchable band. Lengths of stretchable 1 5 thread ate wound onto a plurality of spools. The spools of the thread are then used in a braiding machine to produce a continuous braided tube 'The tube is passed ever a roller or a plurality of rollers, or between rollers, to flatten the tube into a band. The preferred headstrap has a cross-sectional dimension of approximately 6mm wide and 1.5mm thick. 20 According to the most preferred embodinlt, die thread comprises a Lycra (elasrane or spandex) strand with a spun wrapper. The elastane strand may he, for example, 900 denier strand Lycra (elastane or spandex). The spun wrapper may comprise at least one yarn of nylon laments. The wrapper may comprise a primary wrapper yarn and a secondary wrapper yam. Rach yarn may comprise a spun 25 yarn comprising a plurality of nylon filaments. For example, each w-appee may comprise a yarn of nylon filaments., The nylon filaments contribute the colour to thie stretchable thread. For example, for a white headsr.a, the nylon wrapper should comprise white nylon filaments. In preparing a spool of die stretchy thread, preferably multiple dueads (preferably three 30 threads) of stretchy thread are wound onto the spool in parallel, so that each element in the braiding process actMally comprises a bundle of three parratel threads. Preferably, the braiding is conducted on a 16 spool braiding machine, such as a Ratera 16/80 braiding machine available from Talleres Ratera SA of Barelona. Spain. Each spool of thread for the braiding is prepared with three parallel threads, as described above.

60 The braiding machine is configured (for example by setting tensions, speeds or both) to produce a suitable braid. Example settings for the Ratera 16 braiding machine speed control ate A:45 B:20, C:30 and D:35 A headsuap produced in accordance with this description was rested by gradual Cx tension, 5 with the force at cach extension recorded. The force versus extension results for a 300mm length of the prototype strap material are shown in Figure 64. Figures 63A to 63C illustrate features of a preferred headgear strap In particular they illustrate preferred attaIgeIelts for auAching a connector to an end of a suitable strerchy strap material They also illustrate a preferred connector for Connecting The strap to the frame of the 10 imferace. Figures 6311) to 631 illustrate another similar headgear strap which shares many of the features of the headgear strap of Figures 63A to 63C. Except where noted, the following description refers to both embodiments and reference numerals are shared. At least one end of the strap 6304 is terminated, and preferably both ends are terminated, 15 with a connector 6302. Once the complete interface is assembled the connectors 6302 engage the side portions 1016 of the frame. To formn the connector, the flattened tube 6306 is encapsulated by a plastic body 6308 or 6350, for example by overmoulding. In the embodiment of Figures 631D to 633, the band is encapsulated by a comparatively soft 20 taterial such! as a thermoplastic elastomet. The plastic body 6308 tray have gripping features on its outer surfaces, such as bumps or ridges 6324, or recesses 6352. The body 6308 termnates at its other end in an end face which is preferably sized and shaped to snatch the end face of side portions 1016. The, connector and socket are preferably 25 fo-red to provide a tigid connection between the connector and the frame, such that, when engaged, the connector is a rigid ex enksiol of the side potion of the frame. According to this, dic connectors contribute their length to the frame to define the location at which the soft straps depart the frame. T he preferred connection comprises a metal plug portion extending from the end face of 30 the connector 6302, to engage in socket 1062 formed in the end face of the fratne. The metal (preferably steel or titanium or similar matri) phug portion has high stiffness and strength while retaining a compact form. The plug portion may advantrageously he formed from a metal wire 6310. For example the plug portion may be formed from. a length of stainless steel wire.

- 61 The wire may be beat back upon itself and have both ends enclosed by the connector 6302, the wire thus forming a loop protruding from the end face of the connector. To cooperate with tis loop the socket may be in the forn of a slot with an overall shape to match the essentially flat prong forced by the loop. S The loop tray include a limb 6316 including a proruding kink or hump. The protruding kink 6322 is adapted to engage ii a shallow notch 6344 in the socket 1062. Tic notchA 6344 may be formed along one edge surface of the slot. 'Ihe loop may be provided with a protruding end portion 6318 iurthermosr from the connector 6302. The slot may be provided with edge surfaces that closely match at least the lateral 30 profile of the end portion 6318, so as to closely house the end portion with the loop engaged in the slot. This secures the connector against rotation in the plane of the loop The thickness of the slot preferably closely matches the thickness of the wire. This secures the connector against rotation transverse to the plane of the loop. The loop may have a straight lim-b 6320, and the slot a complinentary straight edge Face. 15 These straight faces provide a sliding reference surface to align the connector with the socket during and after engagement. Where one of the limbs of the wire loop is kinked and the other straight, and complimentary surfaces are provided in the slot, the connectors may be formed to have shapes which ensure correct orientation of the connectors relative ro the socket. For example the 20 connectors may have a frunn that is an obvious cortinuadton of die foan of the frame. Where a connector and socket are provided at both ends of the stnap, the connectors (and the sockets) may have reversed orientation. For example, one socket may have depression 6334 at the lower edge face and the other socket may have the depression at the upper edge face. Altemrativelv the connectors may have a form or indication that ensures correct selection F 25 the intended socket, as well as orientation relative to the selected socket. As seen in Figures 63A and 63C, one of the main limbs of the wire loop may he free to move inside a cavity 6314 of the connector hody 6308. Preferably the free end 6340 is the end of the limb 6316 having the protuding kink. The small freedom to move within cavity 6314 allows the wire loop to deflect more than if the end were constrained. This deflection reduces the peak 30 forces required (and generated in the socket) during connection and disconnection of the connector, 'The cavity 6314 comprises a slot opening into tie connector body 6308 from the end face of the connector body. The other end of the wire loop may be fonned to have a portion that is keyed into the 35 material of the connector body. For example a portion of the wire may be bent into a curve and - 62 ovennoulded with plastic material of the connector body. This portion toay overlap inside the connector body with the encapsulated end of the strap 6304. For fanning this connector, the wire loop and the strap may be assembled with a sleeve, and the assembly be ovenoulded, F or example, the sleeve (which may be plastic>, may have a 5 blind cavily that receives the end 6340 of the wire loop, and an ope-n ended cavity that receives the other end of the wire loop (through one end of the cavity) and the end of the strap throughh the other end of the cavity). The sleeve may then be overimoulded, or at least the open ended cavity holding the strap and intended 5ied end of the loop may he filed. Alernatively, the sleeve mat'y be formed in two halves, capped together over the wire loop. The two halves may, for example, be 10 hanged together. The halves may also clip togeTher over the end of the band 6306 and nm roughly grip Le end of the band before overnoukdng. For example, gripping protrusions 6360 may engage the end 6362 of the band. According to the einbodiment of Figures 63D To 63, the soft cover material 6350 is provided by overmoulding the connector with a soft material such as a thermoplastic clastoner 15 along a length of the very flexible foppy band 6306 beyond thbe sleeve. This leads to a flexible portion 6370 transition ing between a rigid portion 6372 of the connector and the very supple strap. Preferablv this flexible portion is progressively more flexible moving away from the rigid portion 6372. For example, the overmoukded cover portion may taper extending away from the sleeve, indents may be pro-vided in the cover (such as depressions 6352) or bot. 20 On masks where the headgear strap will connect in a rigidly protruding fashion (such as in some of the embodiments of the masks described herein), tie extending soft portion of the connector provides a soft buffer against impact from the protruding hard porDion or prong. PreFerably the soft portion extends from 5mm to 60mm along die band or strap, most preferably from .0tnrn to 20mm. The soft matruil my be chosen from a wide range of soft 25 plastics with consideration given to bonding with the strap material and the sleeve material With this connector, one of the edge surfaces of the socket 1062 may include a first portion 6332 that matches the. end portion 6318 of the loop, a depression or notch 6334 that, matches the protuding kink 6322, a bump 6366 which secures the kink 6322 in the notch 6334, and a recessed lead in region 6338, which allows the loop to pass well into the slot before requiring the largest 30 connection force to push the kink 6322 past the bump 6366. The described connector is compacL, acts as an extension of the frame of the interface, and has a simple and intuitive method of connection and disconnect on. Figures 58 to 61 illustrate another parienr interface incorporating a seal substanallya described earlier, and like Figures 10 to 12 includes features that may eliminate or reduce the need 35 for additional support to the conduit. According to this embodiment, the body of the mask - 63 includes depending stabilzers 6102. A depending stabilizer is provided at eaca side of the mask body. Each depending stabilizer extends beyond the perimeter of the rash seal and includes a fout 6104 to engage against the upper lip of the wearer. Preferably, the stabilizer does not extend beyond the inside surface of the seal, but is spaced forwards from the inside surface of de seal, 5 with the feet 6104 located in a position such that with the mask donned and in use syrmmericaliy on the patient, the feet 6104 of the depending stabilizers do not contact the wearer. Each foot 6104 may include a pad 6106 of soft material such as a soft polymer or elastomer foam or a section of hollow silicone cxtasIon. The stabilizers be. integrated with the seal rather than the frame, for example, being integrally fonred as a moulded silicone body extending frorm adjacent the central 10 opening to protrude beyond the lower edge of the seal 1n this case, features on the mask body could secure the position of the in board ends of the stabilisers. Each stabilizer extends in a downward direction to a region below the scal, and is intended to engage in the area of the upper lip of the patient in the area bounded by the mouth, the nose md the nasolabial folds and, preferably, not against the cheeks of the patient. Accordingly, the feet 15 are ptofiled and positioned to fit within this area. Each stabiizer 612 and ann 6108 extending from the lateral central portion 6110 of the mask body. The for, of this arn, and thei tn-iel-al of this arm tmay bec that the arm is rigid, or that the arm has a desired degree of flexiblity. Generally, this arm should be rigid. T'he purpose of the stabilizers is to reside closely spaced from the upper lip portion of the 20 user vhen the interface is correctly placed and to contact the upper hp region of the user when the interface is rocked to one side or the otter relative to the user's nose, for example, under the influence of the supjly conduiL Gentle pressure on the foot 6104 of the stabilizer, which is laterally spaced from the centre line of the mask, prcfcrably toward the extreme edges of the mask, supports the mask against these side forces from the conduit, stopping the mask rocking too fat 25 across the face and brealing the scal. Fnbrrimore, the stabilizers depend below the mash and support the mask if the weight of the conduit tends to totate mask forward. In that case, the feet 6104 of both stabilizers will contact the ussr's upper li and support the position of the mask. The stabilzers are illustrated in prefered For as having a substantially :igid construction, 30 but with flexible or soft pads 6106. flowever to account for variations in patient geometry, these stabilizers could lie a selectable appendage, with a connection arrmngement to the mask allowing replacement with stabilizers of a different form. Alternatively the stabilizers could be made to bc adjusted, such as by providing hinge portions capable of multiple fixed positions along the length of the stabiliser, or at the junction of the arms and feet or both Alternatively, the ams could be - 64 formed of a nalleablC materal which is capable of substantial yield. According to this, the arms could be flexed into a desired position by yielding of the material and stay in that position. In the embodiment with hinging of the arms or feet, a linkage arrangement could be provided to link the movement of each of the stabilizers, or the stabilizer may bc individually or 5 collectively supported in position by a spring or springs or other resilient member. With the addition of the stablbers, the mask may be sufficiently secure and placed ott the patient without -any desire For additional support t fthe conduit. Ti.s in turti mar allow a iotemr lang th of lexi coupling tube 6120 Accordingly, the flexible coupling tube 62.10 (which would typically be mluch mnore fle-ible than the inam supply conduit) can be reduced in length to between 10 Scm and 15cm, and preferably abOut I C1 . In systems that incuC a humidiied gases supply and a heated main supply conduit, this short fexible coupling tuibe is usually unheated. Where the coupling tube needs to be supported by a lanyard or collar, there is a minimum length generally exceeding 15cem. If the requirement for the lanyard in collar is elinilnated, the shorter coupling tube is only provided for flexibility, to de-couple the relatively rigid supply conduit from the mask 15 and facilitate freedom of movement of the wearer's head As the coupling tube is typically unheated, the hurmidity of the gases carried in the tube can rainout on the cooler wall surface creating collections of water which can ultimately be blown into the user's nostrils creating discomfort. Providing a shorter tube, as allowed by the lip stabilisers, reduces the likely rainout in the conduit. 20 The interface configuration incorpo-rating a single supple headstrap, a nasal seal, a low pro File frame which canJ. stabiise oi the upper lip, all in a one size fits all package (pr erbI both the headstap and the seal) can be enhanced where ie short coupling tube is especially supple. By the tube being supple, we triean' that it bends easily under applied forces- For example, suitable tubes may meet the test criteria explained below with reference to Figure 65. 25 According to the test: of Figure 65, a 1 50mm length of tube is clamped at each end to a cylindrical support at each end extending into the bore of the tube. This leaves approximately 130rmin of the tube suspended or bridging freely between the supported ends. ThiAs bridging portion should be in a relaxed state, neither contracted or extended. A lateral force of SN at the centre of the tube should lead to a deflection greater than 13mm. 30 A number of examples of patient interface aspects of the interfaces, and variations on each aspect, have been discussed with reference to other Figures. The present application contemplates that an interface may incorporate sone aspects but not other aspect" For example, an interface m'ght incorporate aspects of the mask while using a different arrangement for securing the mask to the user. .An interface night include a different mask while using inventive aspects of the strap to 35 secure that rask to tie user. An in-erface may incorporate aspects of the mask but not make use -65 of a similar, or any, structure for supportng the weight of the conduit from the body of the patient. All of these variatons are considered within the scope of this application.

Claims

1. A patient interface comprising: a single loop headstrap, a mask for covering at least the nostrils of the user, 5 the single lop Ieadstrap extending from the mo. ask at either end, a swivel cr ball joint: ai lte mask to couple a supply conduit to the mask in use to allow rotation of the supply conduit through different angles and oricntations relative to the mask.

2. A patient interface as claimed in claim 1 wherein the mask includes an inflatable seal with 10 an air supply apertre and a pair of protruding nostril locators protruding from the seal, each nasal locator including an oudet aperture

3. A patient interface as claimed in claim 2 wherein the seal inflates under internal pressure from a pressurized gases supply and wlien pressed against the face of a user, creating a seal with the 15 nose or face of the user in addition to any seal provided by the nasal locators.

4. A patient Interface as claimed in claim 2 wherein the interface includes a frame having a gases inlet for connection with a gases supply conduit, and a gases outlet including a protruding lip, and die gases Supply aperture of the seal is engaged or engagable over the protruding lip of the 20 frame,

5. A patient interface as claimed in claim 2 wherein the seal, in use, fonmus a substantially continuous scal against the user's nose and face that surrounds the nostril locators, 25

6. A patient interface as claimed in claim 2 wherenr except for a region immediately adjacent and including the nostril locators and immediately adjacent and including the air supply apertre, the seal is supple, and the region immediately adjacent and including the inlet opening and has any stutable stiffness. 30

7. A patient inteface as claimed in any one of claims I to 6 including at least a pair of extended support memribers ats the perimeter of the mask, die support members located either side of the mask such that they may, but dc not accessanly, contact options of the face of the user in use. - 67

8. A patient interface as claimed in claim 4 wheii the strap extends froA one side portion of the frame to the other side portion of the frame, the strap being sufficient to pass around the back of the head of the user. 5

9. A patient interface as claimed in any one of claims I to 8 including a short length of supple conduit connected to the swivel or ball joint,

10. A patient inter-face as claimed in any one of claims 2 to 6 including a laterally extended support that can press on a lower facial portion of the user outside the periphery of the seaL 10

11 A patient interface as claimed in claim 10 wherein the laterally extended support can press on the lower cheek portion of the user.

12. A patient interFace as claimed in claim 10 wherein the laterally extended support may- only 15 occasionally contact the face of the user in use.

13. A oatienIt intertace comtrising: a mask for coveting at least the nostris ofdte user, and including a sea! boly aid a frame connected with the seal and a laterally extended support that can press on a lower facial portion of 20 the user outside the periphery of the seal.

14. A patient interface as claimed in claim 13 wherein the mask includes an inflatable seal with an air supply aperture and a pait of protruding nostril locai:ors pioLnuding ft0 he seal, each nasal locator including an outlet aperture, 25

15, A patient interface as claimed in claim 14 wherein the seal inflates under intemal pressure from a pressurised gases supply and when pressed against de face of a user, creating a seal with tihe nose or face of the user in addition to any scad provided by the nasal locators. 30

16. A patient interface as claimed in claim 14 or clairn 15 wherein, in usc, the side wall of the envelope rolls to accommodate movement of the mask frame relative to the rnse, wherein rolls means -that the portion of the envelope adlacem!. to the frame reduces aL one side and extends at die other, and the coresponding portions adjacent the &cc extend ar one side and reduce at the other- -68

17. A patient interface as claimed in any one of chums 13 to 16 wherein the frame includes at least a pair of extended support members at die perimeter, the support rnenbers located either side ot thc frame such that they may, but do not necesnnily, contact portions of dhe face of irhe use in use.

I B. A patient interface as claimed in any one of claims 13 to 17 including a single loop strap extending from one side portion of the frame to the other side portion of the frame, the strap being sufficient to pass around the back of the head of the uSer. 10

19. A patient interface as claimed in ny one of claims 13 to 18 wherein the laterally extended support can press on the lower cheek portion of the user.

20. A patient interface as claimed in any one of claims 13 to 19 wherein the laterally extended support tray only occasionally contact the fa ce of the user in use. 15