Seal forming portion, pad and cushion for a patient interface and method of manufacturing

Abstract

It is discloses a patient interface 3000 comprising a seal forming portion 11, a pad 10, and a cushion 20. The seal forming portion 11 may comprise a base surface 111 and a plurality of fibers 112 fixed to and extending away from said base surface 111 for contacting a patient's skin. The cushion 20 may comprise at least along a portion of the circumference a first structure 22 having an elongate section 24 joined with at least one end section 26 oriented substantially perpendicular or at an angle to the elongate section 24. A first end A of the elongate section 24 may be connected or connectable to a frame member 30. The end section 26 may be provided at an opposing second end B of the elongate section 24. The pad 10 may comprise a resilient foam material layer with the seal forming portion 11. The pad 10 may be adapted to be connected to the cushion 20.

Claims

1. A patient interface comprising a seal forming portion for contacting a patient's skin, a pad, and a cushion; wherein the pad comprises a resilient foam material layer constituting a base surface of the seal forming portion, wherein the pad is adapted to be connected to the cushion, wherein the seal forming portion comprises the base surface and a plurality of fibers fixed to and extending away from said base surface for contacting the patient's skin; and wherein the cushion comprises at least along a portion of a circumference a first structure having an elongate section joined with at least one end section oriented substantially perpendicular or at an angle to the elongate section, wherein a first end of the elongate section is connected or connectable to a frame member, and wherein the at least one end section is provided at an opposing second end of the elongate section, wherein the first structure is a T-beam shaped structure, wherein the elongate section is a web portion and the at least one end section is a flange portion, and wherein the pad is connected to the flange portion.

2. The patient interface according to claim 1, wherein the flange portion is connected or connectable with the pad comprising the seal forming portion.

3. The patient interface according to claim 1, wherein at least a portion of the flange portion is adapted to rotate relative to the second end of the web portion.

4. The patient interface according to claim 1, wherein the flange portion comprises two arms extending from the second end of the web portion in a lateral direction.

5. The patient interface according to claim 4, wherein the flange portion is adapted to rock around the second end, the two arms of the flange portion being rocker arms, wherein the flange portion is adapted to rock around the second end when the patient's skin is in contact.

6. The patient interface according to claim 1, wherein the flange portion is adapted to rock around the second end, and wherein the cushion is provided with a resilience in a nose receiving portion of the cushion so as to clamp the cushion on a ridge of the patient's nose.

7. The patient interface according to claim 1, wherein the web portion is adapted to bulge in a lateral direction.

8. The patient interface according to claim 1, wherein the cushion comprises at least one bellows structure and/or pre-shaped bulge.

9. The patient interface according to claim 1, wherein at least one of the plurality of fibers has a length measured from a proximate end to a distal end between about 0.01 and 5.0 mm.

10. The patient interface according to claim 1, wherein the plurality of fibers provide a higher resilience in the nose ridge area than in other areas of the seal forming portion.

11. The patient interface according to claim 1, wherein the plurality of fibers are made from any one from the group consisting of: cotton, wool, viscose, nylon, and cellulose.

12. The patient interface according to claim 1, wherein the pad has a pad thickness between about 1.5 mm to 26 mm.

13. The patient interface according to claim 1, wherein the pad is provided with a higher resilience than the cushion.

14. The patient interface according to claim 1, wherein the pad comprises a portion of reduced stiffness to facilitate relative movement of portions of the pad adjacent the patient's nose region.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

(1) The present technology is illustrated by way of example, and not by way of limitation, in the figures of the accompanying drawings, in which like reference numerals refer to similar elements including:

(2) Treatment Systems

(3) FIG. 1a shows a system in accordance with the present technology. A patient wearing a patient interface 3000, receives a supply of air at positive pressure from a PAP device 4000. Air from the PAP device is humidified in a humidifier 5000, and passes along an air circuit 4170 to the patient.

(4) FIG. 1b shows a PAP device in use on a patient with a nasal mask.

(5) FIG. 1c shows a PAP device in use on a patient with a full-face mask.

(6) FIG. 1d is a front view of a face with several features of surface a natomy identified including the lip superior, upper vermillion, lower vermillion, lip inferior, mouth width, endocanthion, a nasal ala, nasolabial sulcus and cheilion.

(7) FIG. 1e is a side view of a head with several features of surface anatomy dentified including glabella, sellion, pronasale, subnasale, lip superior, lip inferior, supramenton, nasal ridge, otobasion superior and otobasion inferior. Also indicated are the directions superior & inferior, and anterior & posterior.

(8) FIG. 1f is a further side view of a head. The approximate locations of the Frankfort horizontal and nasolabial angle are indicated.

(9) FIG. 1g shows an anterolateral view of a nose

(10) Patient Interface

(11) FIGS. 2 to 12 show a patient interface 3000 in accordance with the present technology, wherein

(12) FIG. 2 shows preferred examples of seal forming portions.

(13) FIG. 3 shows a side view of a preferred patient interface comprising a pad arranged on a cushion of a patient interface.

(14) FIG. 4 shows a cross sectional view of a preferred patient interface comprising a pad arranged on a cushion of a patient interface.

(15) FIGS. 5 and 6 show an enlarged portion of a preferred patient interface comprising a pad arranged on a cushion of a patient interface.

(16) FIG. 7a shows a sectional view of the mask position seen from the chin side to illustrate the situation of the patient's nose just before biasing the mask cushion inward to achieve the clamping effect.

(17) FIG. 7b shows a non cross-sectional view of the same mask position being applied to the patient's face, seen from the forehead side The arrows indicate deformation and/or movement of the pad and cushion at the nose ridge, preferably at the nasal bones, lateral cartilage and/or sepal cartilage, of the patient.

(18) FIGS. 8a and 8b show cross sectional views of a pad at a position as indicated in FIG. 9b,

(19) FIGS. 9a and 9b show top views on (parts of) a preferred sealing flange portion.

(20) FIGS. 10a-10C shows three dimensional views of an exemplary mask in line with the present technology wherein

(21) FIG. 10a shows a diagonal front view.

(22) FIG. 10b shows a diagonal back view.

(23) FIG. 10c shows a side view.

(24) FIG. 11a shows a side view of a cushion and pad according to the present technology.

(25) FIG. 11b shows a cross sectional side view.

(26) FIG. 11c shows detail A of FIG. 11b.

(27) FIG. 11d shows detail B of FIG. 11b.

(28) FIG. 12 shows different three dimensional cross sectional views of preferred pads of the present technology and enlarged details thereof.

(29) FIG. 13 shows a side view of the mask in use. The patient interface 3000 with a frame member 30 may be, preferably removably, held by a frame element comprising the forehead support 3700. The curved arrows indicate the movement of the upper portion of the pad 10 and/or the cushion 20, i.e. the movement of the apex P, while being positioned on the nose. The rotational, rocking and/or pivoting movement inwards to the plenum chamber 3200 may occur simultaneously to the movement in the direction D depicted in FIG. 5. The portion contacting the nose ridge as well as directly adjacent left and/or right portions of the pad 10 and/or cushion 20 may rotationally move upon insertion of the nose into the plenum chamber 3200. The direction of the movement of the portion contacting the nose ridge as well as directly adjacent left and/or right portions may differ. The clamping region (here shown as a dashed line) may also be located at other locations not depicted in FIG. 13.

DETAILED DESCRIPTION OF EXAMPLES OF THE TECHNOLOGY

(30) Before the present technology is described in further detail, it is to be understood that the technology is not limited to the particular examples described herein, which may vary. It is also to be understood that the terminology used in this disclosure is for the purpose of describing only the particular examples discussed herein, and is not intended to be limiting.

(31) Treatment Systems

(32) The present technology comprises apparatus for treating a respiratory disorder. The apparatus may comprise a flow generator or blower for supplying pressurised respiratory gas, such as air, to the patient via an air delivery tube leading to a patient interface 3000.

(33) Nasal CPAP for OSA

(34) The present technology may comprise a method of treating Obstructive Sleep Apnea in a patient by applying nasal continuous positive airway pressure to the patient.

(35) A supply of air at positive pressure may be provided to the nasal passages of the patient via one or both nares.

(36) In certain embodiments of the present technology, mouth breathing is limited, restricted or prevented. Also, as will be appreciated, CPAP treatment may be provided via the patient's mouth.

(37) Patient Interface 3000

(38) A non-invasive patient interface 3000 in accordance with one aspect of the present technology comprises the following functional aspects: a seal-forming structure 3100, a plenum chamber 3200, a positioning and stabilising structure 3300 and a connection port 3600 for connection to air circuit 4170 (FIG. 1b, 3, 4). A functional aspect may be provided by one or more physical components. One physical component may provide one or more functional aspects. In use the seal-forming structure 3100 may be arranged to surround an entrance to the airways of the patient so as to facilitate the supply of air at positive pressure to the airways.

(39) Seal-Forming Structure 3100

(40) A seal-forming structure 3100 may provide a sealing-forming portion 11, preferably provided on a pad 10, and a cushion 20. The cushion may at least partially provide a cushioning function.

(41) A seal-forming structure 3100 in accordance with the present technology may be constructed from a soft, flexible, resilient material such as silicone.

(42) The seal-forming structure 3100, preferably the cushion 20, may comprise in a portion of the cushion a sealing flange and a support flange. Preferably the sealing flange comprises a relatively thin member with a thickness of, e.g., less than about 1 mm, for example about 0.25 mm to about 0.45 mm, that extends around the perimeter 3210 of the plenum chamber 3200. The support flange may be relatively thicker than the sealing flange. The support flange may be disposed between the sealing flange and the marginal edge of the plenum chamber 3200, and may extend at least part of the way around the perimeter 3210. The support flange preferably is or includes a spring-like element and functions to support the sealing flange from buckling in use. In use the sealing flange may readily respond to system pressure in the plenum chamber 3200 acting on its underside to urge it into tight sealing engagement with the face.

(43) The seal-forming portion of the non-invasive patient interface 3000 may comprise a pair of nasal puffs, or nasal pillows, each nasal puff or nasal pillow being constructed and arranged to form a seal with a respective naris of the nose of a patient.

(44) Nasal pillows in accordance with an aspect of the present technology include: a frusto-cone, at least a portion of which forms a seal on an underside of the patient's nose; a stalk, a flexible region on the underside of the cone and connecting the cone to the stalk. In addition, the structure to which the nasal pillow of the present technology is connected includes a flexible region adjacent the base of the stalk. The flexible regions can act in concert to facilitate a universal joint structure that is accommodating of relative movementboth displacement and angularof the frusto-cone and the structure to which the nasal pillow is connected. For example, the frusto-cone may be axially displaced towards the structure to which the stalk is connected.

(45) The non-invasive patient interface 3000 may comprise a seal-forming portion that forms a seal in use on an upper lip region (that is, the lip superior) of the patient's face.

(46) The non-invasive patient interface 3000 may comprise a seal-forming portion that forms a seal in use on a chin-region of the patient's face.

(47) Seal Forming Portion 11

(48) FIG. 2 discloses three seal forming portions 11 in accordance with preferred alternative or combined technologies of the disclosed technology. The seal forming portions may be manufactured using one of the disclosed methods. Left seal forming portion 11 comprises fibers 112 extending from the surface of resilient material 114. Fibers 112 are fixed to surface 112 with an adhesive 113. Fibers 112 form an angle with the base surface of approximately 90. Often, the fibers 112 will be randomly distributed. The second seal forming portion located in the middle of FIG. 2 comprises fibers 112 arranged in a plurality of tufts. The tufts are looped at the second free end adapted to get in contact with a patient. The looped distal ends provide an increased wearing comfort. The right sealing portion 11 in FIG. 2 is provided with fibers 112 in a multilevel configuration, i.e. with fibers generally having two or more different, preferably predefined, lengths l.sub.112a, l.sub.112b. Although seal forming portion 11 is depicted in the Figures in conjunction with the particularly advantageous cushion 20 and pad 10, seal forming portions 11 may also be used with other pads and/or other cushions.

(49) Pad 10

(50) FIGS. 3 to 8 and 10 to 11 show pad 10 arranged on cushion 20 of patient interface 3000. The pad may be manufactured using one of the disclosed methods. As best seen in FIGS. 3, 4, 7a, 7b, 10 and 11, pad 10 extends along the entire perimeter 3210 of the plenum chamber, i.e. the perimeter of the entrance to the airways of the patient. Pad 10 is generally flat. That is, the width w.sub.10 of the pad is significantly greater than its thickness t.sub.10. The front or face contacting surface 11 is contacting the user and forms the seal against the user's face. Although not shown in FIGS. 3 to 7b, face contacting surface 11 preferably comprises the above described seal forming portion 11 with fibers 112. The back surface of pad 10 is adapted to contact cushion 20 in cushion contacting portion 13. The lateral side surfaces at lateral sides 101, 102 may be generally round.

(51) FIG. 12 depicts further preferred shapes of pad 10. Details C and E depict rounded lateral sides 101, 102 whereas the sides of details D and F are generally flat. Overall, details D and F have a flat and rather rectangular of trapezoid shape. The shape may be influenced by the manufacturing process.

(52) FIG. 12 shows on the top left a cross sectional three dimensional view of a pad 10 according to the present technology wherein right below an enlarged detail C of said pad is shown. Similarly, the pads shown on the top right, bottom left and bottom right of FIG. 12 show preferred cushions according to the present technology with respective enlarged details of a cross sectional section thereof. As will be readily noted, the outer circumferential side surface 102 of the cushion may be substantially flat, as, e.g., shown in the top right example, or curved, as shown, e.g., in the top left example. The same applies to the inner circumferential side surface 101 as shown in the examples on the top left and right of FIG. 12. The example on the bottom left shows a rounded outer circumferential surface 102 in combination with a straight inner circumferential surface 101 having a radius, preferably corresponding to about to of the pad thickness, at the transition to the seal forming portion or surface 11. This may ease the comfort of the pad when worn by a user. While the pads on the top left and right as well as the bottom left show a substantially flat or planar, eventually slightly concave seal forming portion 11, the pad depicted at the bottom right (see detail F) is exhibits a convexly curved cross-sectional profile.

(53) FIGS. 8a, 8ab are cross sectional views as indicated in FIG. 9b, i.e. views perpendicular to the circumferential direction 3210. As best seen in FIG. 8a, 8b, pad 10 may have different cross-sectional shapes. E.g., cushion contacting portion 13 may be configured to be generally flat while face contacting portion 11 may have a profiled shape. Face contacting portion 11 may have a first concave cross sectional portion followed by a convex peak cross sectional portion and a second concave cross section portion (FIG. 8a and detail F in FIG. 12). Alternatively or additionally, the cross sectional shape may be configured as a convex shape with a gradually reduced gradient towards the outer section of pad 10 as shown in FIG. 8b. Any suitable 2.5D configuration may be applied.

(54) As shown in FIG. 9a, flange portion 26 may be provided with a slit 15 reducing the stiffness of flange portion 26. Portions adjacent to slit 15 at apex P of flange portion 26 depicted in FIG. 9a and located in the nose receiving portion may easier move relative to each other. Such a configuration may facilitate the clamping (FIGS. 5, 7a, 7b). As shown in FIG. 9b, pad 10 may be provided with a corresponding notch or pad slit 15, too.

(55) The pad is provided with a high resilience and is configured to micro-adapt to the patient's face and/or to follow the movements of cushion 20, e.g. pivoting movements of flange 26 depicted in FIG. 5, 7a, 7b. Preferably, as discussed below, the pivoting movements of flange 26 together with other suitable deformations of the cushion achieve a macro-adaptation to the contour and physiognomy of a patients face while the pad provides for a micro-adaptation to said face to enhance, e.g., comfort, sealing characteristics and thus compliance.

(56) Although pad 10 is depicted in the Figures in conjunction with the particularly advantageous seal forming portion 11 and cushion 20, pad 10 may also be used with other cushions and/or other seal forming portions.

(57) Cushion 20

(58) FIG. 5 is an enlarged view of the apex region P depicted in FIG. 4. Cushion 20 supports pad 10 which is positioned at flange 26. The depicted mask comprising cushion 20 and pad 10 may be manufactured using one of the disclosed methods. Flange 26 and web 24 together form a T- or I-shaped beam shape or structure 22. The first end A of structure 22 is fixed to shell or frame 30 of patient interface 3000. Here, a generally chevron- or V-shaped flange of shell or frame 30 is connected to first end A of web portion 24, for instance by co-molding. Part of the shell may also be made of the cushion material. I.e. the cushion may continue to the front area of the patient interface forming part of the shell. Shell or frame 30 may be integrally molded with cushion 20 (FIGS. 3 to 7b). As indicated by arrows in FIG. 5, at least a portion of flange 26, preferably the whole flange 26 may pivot or rock around the second end B. Pad 10 is adapted to follow this movement. When a patient first contacts pad 10 at or close to inner or lateral side 101 pad 10 and flange 26 may pivot around second end B and inner side 101 may move generally in direction C. Depending on the individual shape of the patient's face, it may also be the case that it first contacts the pad at or close to the outer side. In this case, pad 10 and flange 26 may pivot around second end B towards the outer side, opposite direction of C. The cushion and pad, due to their resilience and spring features, may be adapted to cope with and tolerate the resulting torsion as adjacent parts bend inwardly or outwardly. This mechanism allows the system to adapt itself to the patient's individual anatomical distinctiveness in a particularly advantageous fashion. Direction C is opposite the application direction during positioning the mask. I.e. at inner side 101 pad 10 generally moves toward the inner part of cushion 20 (meaning toward the plenum chamber 3200). At the same time, portions of first arm 261 move in generally the same direction. Preferably, portions of second 262 arm may move simultaneously in the opposite direction. I.e. generally in the application direction of the patient interface or towards the patient's face as indicated by curved arrows in FIG. 5. The second end B of web 24 is a center around which the two arms 261, 262 of flange 26 may rock. This rocking motion may be suitable to ensure a near-constant application of the required sealing force onto the patient's face over the entire pad surface, while simultaneously avoiding local areas of increased force.

(59) The resilience of cushion 20 is influenced by the configuration of the first and second arms 261, 261. FIGS. 5 and 6 show the configuration in the apex P region of patient interface 3000. The configuration of the T- or I-beam structured rocker may vary around the perimeter of the entrance to the patient's airways. For instance, arm 261 may be configured more pliable and/or longer in a portion of sealing structure 3100 where a high resilience is required whereas arm 261 may be shorter and/or stiffer in a portion of the sealing structure 3100 which may transmit more interface holding forces to a patient's face. The relative position of the rocker center or second end B may also vary around the perimeter aiming to influence the resilience. The second end B may be located more toward to outer side 102 of flange 26 in portions of sealing structure 3100 in which a high resilience is required than in portions of the sealing structure which may transmit more interface holding forces to a patient's face. The location of the second end B on the flange structure may influence the behavior of the rocking motion in such a way that the system will, in specific areas, more readily deflect towards the mask interior or towards the mask exterior. This may be advantageous in that in protruding areas such as, e.g., the nose ridge or chin, the cushion and pad will be able to deflect towards the interior, whereas in flatter areas such as, e.g., the cheeks, the cushion may be more poised to bend outward. This may be advantageous in enabling the structures to adapt to, and to establish a reliable seal at, different physiological sites in the patient's face. The first arm length or width is referred to as w.sub.261 while the second arm length or width is referred to as w.sub.262. Here, in the shown cross-section, the second arm width is smaller or shorter than the first arm width. The resilience of patient interface 3000, inter alia, may be influenced by: 1) the profile and the material of the pad 10 (micro-adaption), 2) the shape of the arms 261, 262 and/or of web portion 24 as well as the material of cushion 20, and/or 3) the relative position of web portion 24 to flange 26 (=ratio of arms length). Accordingly, the disclosed technology provides several design parameters to locally adjust the resilience while having a simple basic design of the patient interface. The simple basic design may allow the use of relatively simple manufacturing processes discussed above without compromising on the comfort.

(60) Moreover, no further time consuming and inappropriate adaption of a patient interface to the individual face of a patient on the macro-adaptation level needs to be carried out. Prior art devices provide semi-rigid plastic deformable cushions which are often inappropriately formed by the patient. In addition, such plastic deformable cushions tend to deform easily, for instance after they are unintentional dropped by a user or even during use.

(61) In one embodiment, flange 26 may only comprise a first arm 261 having portions provided with different arm length and/or different arm stiffnesses thereby varying the resilience of the cushion 20 along the perimeter 3210. By varying the length and/or the stiffness of arm 261, a portion of the first arm 261 located in the nose receiving region may be provided with a higher resilience than another region not located in the nose receiving portion.

(62) Web portion 24 may have an elasticity so as to allow together with above rocker function a clamping onto the patient's nose ridge, preferably on the nasal bones, lateral cartilage and/or sepal cartilage (FIGS. 1g, 5, 7a, 7b, 11) thereby improving the seal. Web portion 24 may be adapted to not significantly collapse when the patient contacts inner side 101. Web portion 24 may be adapted to bulge or move, preferably in a direction D, direction D being generally perpendicular to the main axis of extension of web 24. Web portion 24 may be adapted to move center B of the rocking movement of flange 26 more in a lateral direction D than in the direction of extension of web 24. Preferably, the web 24 is shaped to form a bulge or bellows around the entire perimeter (e.g. FIGS. 11). This bellows is most prominent (e.g. having a smaller radius) where a high resilience is required (e.g. at the nose), and least prominent (e.g. having a bigger radius) where a high stiffness is required (e.g. in the cheeks area). The bulge/bellows will allow the cushion to deflect as the pad comes into contact with prominent features such as the nose. The point B moves roughly in the direction of C, causing the pad and flange features to be pulled inwards in a proximal direction, towards the nose ridge of the patient. The combination of these two effects enables the mask to create a seal by transforming the sealing force, which is applied in a ventral-dorsal plane by the headgear, into a force acting onto the sides of the nose in a proximal direction. This lateral movement of the second end B may further facilitate the clamping of cushion 20 and/or pad 10 onto the patient's nose. When patient interface 3000 is positioned on the nose the laterally displaced rocking center B of web 24 may be biased causing a clamping force on lateral sides of the nose. Cushion 20 and/or pad 10 are provided with a portion of reduced stiffness, here configured as a slit 15. Slit 15 may increase the flexibility or resilience of pad 10 / cushion 20 so as to facilitate the movement indicated by the arrows in FIGS. 5, 7a and 7b and described above. As depicted in FIGS. 11a to 11d, the first and/or second flanges may be provided with at least two portions of different materials. For instance, the first arm 261 may comprise two portions 261-1, 261-2 of different materials. The first portion proximate to second end B may be made of a first material whereas the second distal portion 261-2 may be made of the second material. The first material may be less resilient than the second material. The portions of different materials may be provided around the entire perimeter 3210 of the plenum chamber 3200. Preferably, the portions of different materials are located in sensible areas, e.g. proximal to/around the nose bridge. These portions of different materials may constitute or contribute to the zones of reduce stiffness discussed above.

(63) Although cushion 20 is depicted in the Figures in conjunction with the particularly advantageous seal forming portion 11 and pad 10, cushion 20 may also be used with other pads and/or other seal forming portions.

(64) Plenum Chamber 3200

(65) Preferably the plenum chamber 3200 has a perimeter 3210 that is shaped to be complementary to the surface contour of the face of an average person in the region where a seal will form in use . In use, a marginal edge 3220 of the plenum chamber 3200 is positioned in close proximity to an adjacent surface of the face. Actual contact with the face is provided by the seal-forming structure 3100. Preferably the seal-forming structure 3100 extends in use about the entire perimeter 3210 of the plenum chamber 3200.

(66) Positioning and Stabilising Structure 3300

(67) Preferably the seal-forming portion 3100 of the patient interface 3000 of the present technology is held in sealing position in use by the positioning and stabilising structure 3300 such as a headgear 3300.

(68) Vent 3400

(69) In one form, the patient interface 3000 includes a vent 3400 constructed and arranged to allow for the washout of exhaled carbon dioxide. One form of vent in accordance with the present technology comprises a plurality of holes, for example, about 20 to about 80 holes, or about 40 to about 60 holes, or about 45 to about 55 holes. Preferably the vent is located in the plenum chamber. Alternatively, the vent is located in a decoupling structure, e.g. a swivel.

(70) Decoupling Structure(s)

(71) In one form the patient interface 3000 includes at least one decoupling structure, for example a swivel or a ball and socket.

(72) Connection Port

(73) Connection port allows for connection to the air circuit.

(74) Forehead Support

(75) In one form, the patient interface 3000 includes a forehead support.

(76) Anti-Asphyxia

(77) In one form, the patient interface includes an anti-asphyxia valve.

(78) Ports

(79) In one form of the present technology, a patient interface 3000 includes one or more ports that allow access to the volume within the plenum chamber. In one form this allows a clinician to supply supplemental oxygen. In one form this allows for the direct measurement of a property of gases within the plenum chamber, such as the pressure.

(80) Materials

(81) Silicone or Silicone Elastomer: A synthetic rubber. In this specification, a reference to silicone is a reference to liquid silicone rubber (LSR) or a compression moulded silicone rubber (CMSR). One form of commercially available LSR is SILASTIC (included in the range of products sold under this trademark), manufactured by Dow Corning. Another manufacturer of LSR is Wacker. Unless otherwise specified to the contrary, a preferred form of LSR has a Shore A (or Type A) indentation hardness in the range of about 35 to about 45 as measured using ASTM D2240

(82) Polycarbonate: a typically transparent thermoplastic polymer of Bisphenol-A Carbonate.

(83) Aspects of a Patient Interface

(84) Frame 30: Frame will be taken to mean a mask structure that bears the load of tension between two or more points of connection with a headgear. A mask frame may be a non-airtight load bearing structure in the mask. However, some forms of mask frame may also be air-tight.

(85) Plenum chamber: a mask plenum chamber will be taken to a mean portion of a patient interface having walls enclosing a volume of space, the volume having air therein pressurised above atmospheric pressure in use. A shell may form part of the walls of a mask plenum chamber. In one form, a region of the patient's face forms one of the walls of the plenum chamber.

(86) Seal: The noun form (a seal) will be taken to mean a structure or barrier that intentionally resists the flow of air through the interface of two surfaces. The verb form (to seal) will be taken to mean to resist a flow of air.

(87) Shell 30: A shell will preferably be taken to mean a curved structure having bending, tensile and compressive stiffness, for example, a portion of a mask that forms a curved structural wall of the mask. Preferably, compared to its overall dimensions it is relatively thin. In some forms, a shell may be faceted. Preferably such walls are airtight, although in some forms they may not be airtight. Shell and frame may be configured as one part, either called frame or shell.

(88) Terms Used in Relation to Patient Interface

(89) Curvature (of a surface): A region of a surface having a saddle shape, which curves up in one direction and curves down in a different direction, will be said to have a negative curvature. A region of a surface having a dome shape, which curves the same way in two principle directions, will be said to have a positive curvature. A flat surface will be taken to have zero curvature.

(90) Resilient: Able to deform substantially elastically, and to release substantially all of the energy upon unloading, within a relatively short period of time such as 1 second.

(91) Rigid: Not readily deforming to finger pressure, and/or the tensions or loads typically encountered when setting up and maintaining a patient interface in sealing relationship with an entrance to a patient's airways.

(92) Semi-rigid: means being sufficiently rigid to not substantially distort under the effects of mechanical forces typically applied during positive airway pressure therapy.

(93) Facial Anatomy

(94) (Nose) Ridge (nasal): The nasal ridge is the midline prominence of the nose, extending from the Sellion to the Pronasale.

(95) Lateral nasal cartilage: A generally triangular plate of cartilage. Its superior margin is attached to the nasal bone and frontal process of the maxilla, and its inferior margin is connected to the greater alar cartilage.

(96) Nasal bones: The nasal bones are two small oblong bones, varying in size and form in different individuals; they are placed side by side at the middle and upper part of the face, and form, by their junction, the bridge of the nose.

(97) Lateral nasal cartilage: A generally triangular plate of cartilage. Its superior margin is attached to the nasal bone and frontal process of the maxilla, and its inferior margin is connected to the greater alar cartilage.

(98) Septal cartilage (nasal): The nasal septal cartilage forms part of the septum and divides the front part of the nasal cavity.

(99) Other Remarks

(100) A portion of the disclosure of this patent document contains material which is subject to copyright protection. The copyright owner has no objection to the facsimile reproduction by anyone of the patent document or the patent disclosure, as it appears in the Patent and Trademark Office patent file or records, but otherwise reserves all copyright rights whatsoever.

(101) Unless the context clearly dictates otherwise and where a range of values is provided, it is understood that each intervening value, to the tenth of the unit of the lower limit, between the upper and lower limit of that range, and any other stated or intervening value in that stated range is encompassed within the technology. The upper and lower limits of these intervening ranges, which may be independently included in the intervening ranges, are also encompassed within the technology, subject to any specifically excluded limit in the stated range. Where the stated range includes one or both of the limits, ranges excluding either or both of those included limits are also included in the technology.

(102) Furthermore, where a value or values are stated herein as being implemented as part of the technology, it is understood that such values may be approximated, unless otherwise stated, and such values may be utilized to any suitable significant digit to the extent that a practical technical implementation may permit or require it.

(103) Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this technology belongs. Although any methods and materials similar or equivalent to those described herein can also be used in the practice or testing of the present technology, a limited number of the exemplary methods and materials are described herein.

(104) When a particular material is identified as being preferably used to construct a component, obvious alternative materials with similar properties may be used as a substitute. Furthermore, unless specified to the contrary, any and all components herein described are understood to be capable of being manufactured and, as such, may be manufactured together or separately.

(105) It must be noted that as used herein and in the appended claims, the singular forms a, an, and the include their plural equivalents, unless the context clearly dictates otherwise.

(106) All publications mentioned herein are incorporated by reference to disclose and describe the methods and/or materials which are the subject of those publications. The publications discussed herein are provided solely for their disclosure prior to the filing date of the present application. Nothing herein is to be construed as an admission that the present technology is not entitled to antedate such publication by virtue of prior invention. Further, the dates of publication provided may be different from the actual publication dates, which may need to be independently confirmed.

(107) Moreover, in interpreting the disclosure, all terms should be interpreted in the broadest reasonable manner consistent with the context. In particular, the terms comprises and comprising should be interpreted as referring to elements, components, or steps in a non-exclusive manner, indicating that the referenced elements, components, or steps may be present, or utilized, or combined with other elements, components, or steps that are not expressly referenced.

(108) The subject headings used in the detailed description are included only for the ease of reference of the reader and should not be used to limit the subject matter found throughout the disclosure or the claims. The subject headings should not be used in construing the scope of the claims or the claim limitations.

(109) Although the technology herein has been described with reference to particular embodiments, it is to be understood that these embodiments are merely illustrative of the principles and applications of the technology. In some instances, the terminology and symbols may imply specific details that are not required to practice the technology. For example, although the terms first and second may be used, unless otherwise specified, they are not intended to indicate any order but may be utilised to distinguish between distinct elements. Furthermore, although process steps in the methodologies may be described or illustrated in an order, such an ordering is not required. Those skilled in the art will recognize that such ordering may be modified and/or aspects thereof may be conducted concurrently or even synchronously.

(110) It is therefore to be understood that numerous modifications may be made to the illustrative embodiments and that other arrangements may be devised without departing from the spirit and scope of the technology.

(111) The present invention also covers the exact terms, features, values and ranges etc. in case these terms, features, values and ranges etc. are used in conjunction with terms such as about, around, generally, substantially, essentially, at least etc. (i.e., about 3 shall also cover exactly 3 or essentially radial shall also cover exactly radial).

REFERENCE LIST

(112) 10 pad

(113) 11 seal forming portion

(114) 13 cushion contacting portion

(115) 15 slit; portion of reduced stiffness

(116) 20 resilient cushion,

(117) 22 first structure, T- or I-beam shaped structure

(118) 24 elongate section or web portion

(119) 26 end section or flange portion

(120) 30 frame member, frame, shell

(121) 101, 102 sides

(122) 111 base surface

(123) 112 fibers

(124) 112 fibers arranged in tufts

(125) 112 multilevel arrangement

(126) 113 adhesive

(127) 114 resilient material,

(128) 261 first arm

(129) 261-1, 261-2; 262-1, 262-2 two portions made of different materials

(130) 262 second arm

(131) 3000 patient interface

(132) 3100 seal-forming structure

(133) 3200 plenum chamber

(134) 3210 perimeter of the plenum chamber

(135) 3220 marginal edge of the plenum chamber

(136) 3300 positioning and stabilising structure

(137) 3600 connection port

(138) 3700 forehead support

(139) 4000 PAP device

(140) 4170 air circuit

(141) 5000 humidifier

(142) fiber angle

(143) A first end

(144) B second end

(145) C face contacting side

(146) D lateral direction

(147) 1112 fiber length

(148) 1112a first length

(149) 1112b second length

(150) 124 web portion length

(151) P apex of the pad

(152) t10 pad thickness

(153) t24 web portion thickness

(154) t261 flange portion thickness

(155) t261 first arm thickness

(156) t262 second arm thickness

(157) w10 pad width

(158) w13 cushion contacting portion width

(159) w26 width of the flange portion

(160) w261 first arm width

(161) w262 second arm width w262