Patent ID: 12246131

5 DETAILED DESCRIPTION OF EXAMPLES OF THE TECHNOLOGY

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.

The following description is provided in relation to various examples which may share one or more common characteristics and/or features. It is to be understood that one or more features of any one example may be combinable with one or more features of another example or other examples. In addition, any single feature or combination of features in any of the examples may constitute a further example.

5.1 Therapy

In one form, the present technology comprises a method for treating a respiratory disorder comprising the step of applying positive pressure to the entrance of the airways of a patient1000.

In certain examples of the present technology, a supply of air at positive pressure is provided to the nasal passages of the patient via one or both nares.

In certain examples of the present technology, mouth breathing is limited, restricted or prevented.

5.2 Treatment Systems

In one form, the present technology comprises an apparatus or device for treating a respiratory disorder. The apparatus or device may comprise an RPT device4000for supplying pressurised air to the patient1000via an air circuit4170to a patient interface3000, e.g., seeFIGS.1A to1C.

5.3 Patient Interface

A non-invasive patient interface3000in accordance with one aspect of the present technology comprises the following functional aspects: a seal-forming structure3100, a plenum chamber3200, a positioning and stabilising structure3300, a vent3400, one form of connection port3600for connection to air circuit4170, and a forehead support3700. In some forms a functional aspect may be provided by one or more physical components. In some forms, one physical component may provide one or more functional aspects. In use the seal-forming structure3100is 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.

FIGS.4to28show a non-invasive patient interface6000in accordance with one aspect of the present technology comprising a frame assembly6100, a cushion assembly6175including a seal-forming structure6200, an air delivery connector (e.g., elbow assembly6600), and a positioning and stabilising structure (e.g., headgear6800).FIGS.4and5are exemplary views of the patient interface6000on a patient's head (with arm covers6750for upper arms6134of the frame assembly6100attached), andFIGS.6to10are exemplary views of the patient interface6000with the headgear6800and the arm covers6750removed. In use, one form of the seal-forming structure6200is arranged to surround an entrance to the airways of the patient1000so as to facilitate the supply of air at positive pressure to the airways. The seal-forming structure6200(e.g., constructed of silicone) may also be commonly referred to as a cushion. In some forms, a functional aspect may be provided by one or more physical components. In some forms, one physical component may provide one or more functional aspects.

In one form of the present technology, the frame assembly6100connects as an intermediate component to the cushion assembly6175and the elbow assembly6600. That is, the cushion assembly6175connects to the frame assembly6100(via a first retention feature on the frame assembly) independently of the elbow assembly6600(seeFIG.11), and the elbow assembly6600connects to the frame assembly6100(via a second retention feature on the frame assembly) independently of the cushion assembly6175(seeFIG.12). However, the seal for the air flow path is formed between the elbow assembly6600and the cushion assembly6175, i.e., the frame assembly6100is not in the air flow path (e.g., seeFIGS.13and14). Alternatively, a first seal for the air flow path may be formed between the elbow assembly6600and the frame assembly6100, while a separate second seal may be formed between the frame assembly6100and the cushion assembly6175. In this instance, the frame assembly6100may remain in the air flow path. The retention connections of the cushion assembly6175and the elbow assembly6600to the frame assembly6100are separate and distinct from one another and allow independent engagement/disengagement, e.g., such that the frame assembly6100may remain connected to either of the cushion assembly6175or elbow assembly6600when disconnecting either of these components. For example, this arrangement allows the cushion assembly6175to be disconnected from the frame assembly6100(e.g., to change cushion sizes) while maintaining connection between the frame assembly6100and the elbow assembly6600, yet maintaining the ability to disconnect the elbow assembly6600from the frame assembly6100.

In the illustrated example, the seal-forming structure6200of the patient interface6000of the present technology may be held in sealing position in use by the headgear6800. As illustrated inFIGS.4and5, the headgear6800includes a pair of upper side straps6802and a pair of lower side straps6804connected to a circular crown strap6806that encapsulates the crown of the patient's head. The upper side straps6802connect to the upper headgear connector6130of the frame assembly6100and the lower side straps6804connect to the lower headgear connector6150of the frame assembly6100, e.g., via headgear clips6160. The side straps6802,6804may include an adjustable hook and loop (Velcro™) connection mechanism, e.g., Velcro™-like hook tabs, to facilitate connection and/or adjustment.

FIGS.59to100show a patient interface16000according to another example of the present technology. The patient interface includes a frame assembly16100, a cushion assembly16175including a seal-forming structure16200, an air delivery connector (e.g., elbow assembly16600), and a positioning and stabilising structure (e.g., headgear16800including upper side straps16802, lower side straps16804, and crown strap16806).FIGS.59to61are exemplary views of the patient interface16000with arm covers16750for upper arms16134of the frame assembly16100attached, andFIGS.62to68are exemplary views of the patient interface16000with the headgear16800and the arm covers16750removed.

Similar to the example described above, the cushion assembly16175connects to the frame assembly16100(via a first retention feature on the frame assembly) independently of the elbow assembly16600(seeFIG.67), and the elbow assembly16600connects to the frame assembly16100(via a second retention feature on the frame assembly) independently of the cushion assembly16175(seeFIG.68). That is, the retention connections of the cushion assembly16175and the elbow assembly16600to the frame assembly16100are separate and distinct from one another and allow independent engagement/disengagement.

In the example of patient interface16000, a first seal for the air flow path is formed between the elbow assembly16600and the frame assembly16100, and a separate second seal is formed between the frame assembly16100and the cushion assembly16175. In this example, the frame assembly16100is provided in the air flow path. That is, the elbow assembly16600is structured to establish a hard-to-hard connection and dynamic seal with the frame assembly16100, and the cushion assembly16175is structured to establish a separate hard-to-hard connection and static seal with the frame assembly16100.

Also, in the example of patient interface16000, the frame assembly16100includes a lockout feature along the opening16105that is structured and arranged to prevent direct connection or insertion of the air circuit4170, e.g., air delivery tube. This arrangement requires use of the elbow assembly16600to interconnect the frame assembly16100and the air circuit4170, thereby ensuring that the elbow assembly16600(and its vent and anti-asphyxia valve (AAV)) are present in the system.

In the example shown inFIGS.4to28and59-100, the patient interface is a full-face/oro-nasal interface type including a seal-forming structure6200structured to form a seal around the patient's nose and mouth. However, aspects of the present technology may be adapted for use with other suitable interface types, e.g., nasal interface, nasal prongs.

For example,FIGS.29to54Cshow a non-invasive patient interface7000in accordance with another aspect of the present technology. In this example, the patient interface is a nasal interface type including a seal-forming structure7200structured to form a seal around the patient's nose. The patient interface7000comprises a frame assembly7100, a cushion assembly7175including the seal-forming structure7200, an elbow assembly7600, and a positioning and stabilising structure (e.g., headgear7800). Similar to the above, the cushion assembly7175connects to the frame assembly7100independently of the elbow assembly7600(e.g., seeFIG.35), and the elbow assembly7600connects to the frame assembly7100independently of the cushion assembly7175(e.g., seeFIG.36). In this example, the seal for the air flow path is formed between the elbow assembly7600and the cushion assembly7175(e.g., seeFIGS.37and38).

Frame Assembly

As best shown inFIGS.18to26, the frame assembly6100includes a shroud or wall member6110, an upper headgear connector6130provided to an upper portion of the shroud6110, and a lower headgear connector6150provided to a lower portion of the shroud6110. The frame assembly6100provides a connection between the cushion assembly6175and the elbow assembly6600, and also provides a connection between the cushion assembly6175and the headgear6800, e.g., either in a removable fashion or a more permanent fashion, to allow sealing forces to be transferred to the cushion assembly6175from the headgear6800. In the illustrated example, upper and lower headgear connectors6130,6150provide a 4-point connection to the headgear6800.

The shroud6110(e.g., constructed of a relatively hard plastic material such as polycarbonate) includes an opening6105through which the elbow assembly6600sealingly engages with the cushion assembly6175(e.g., seeFIGS.13and14).

In the illustrated example, the opening6105is bounded by an annular flange6115that protrudes forwardly from an anterior or front side of the shroud6110. The flange6115includes a rim6117along its free end which defines a circular channel6120structured to interface with the elbow assembly6600.

The posterior or rear side of the shroud6110includes a plurality of spring arms6125(e.g., 3, 4, 5, or more spring arms) spaced around the opening6105. Each of the spring arms6125includes a barbed end structured to provide a mechanical interlock, e.g., snap-fit connection, with the cushion assembly6175.

In an alternative example, as best shown inFIGS.75to100, the frame assembly16100includes a shroud or wall member16110, a pair (i.e., right and left) of upper headgear connector arms16134(each comprising two flexible portions16140,16145) extending from respective sides of an upper portion of the shroud16110, and a pair (i.e., right and left) of lower headgear connector arms16154extending from respective sides of a lower portion of the shroud16110.

In the illustrated example, the opening16105of the shroud16110(e.g., constructed of a relatively hard plastic material such as polycarbonate) is bounded by an outer annular flange16115and an inner annular flange16125.

The outer annular flange16115protrudes forwardly from an anterior or front side of the shroud16110. The flange16115includes a rim16117along its free end which defines a circular channel16120structured to interface with the elbow assembly16600.

The inner annular flange16125protrudes rearwardly from a posterior or rear side of the shroud16110. The flange16125includes a plurality of tabs or catches16127along its perimeter (e.g., seeFIGS.70,76,84,86, and88), e.g., 2, 3, 4 or more tabs, which are structured to provide a mechanical interlock, e.g., snap-fit connection, with the cushion assembly16175so as to releasably connect the frame assembly16100to the cushion assembly16175. In the illustrated example, the tabs16127are provided on superior and inferior sides of the flange (i.e., north and south sides), however alternative arrangements are possible, e.g., tabs provided on anterior and posterior sides of the flange (i.e., east and west sides).

In addition, a radially inwardly extending ridge16400protrudes from the flange16125into the opening16105. As described in more detail below, the ridge16400acts as a stop to prevent over-insertion of the elbow assembly16600into the frame assembly16100. Also, the ridge16400provides a dynamic face seal with the elbow assembly16600.

Also, the ridge16400includes a plurality of projections16405along its perimeter (e.g., 2, 3, 4, or more projections), which are structured to provide a lockout feature along the opening16105to prevent direct connection or insertion of the air circuit4170, e.g., air delivery tube, to the frame assembly16100. This arrangement ensures that the elbow assembly16600(and its vent and anti-asphyxia valve (AAV)) is used to interconnect the frame assembly16100and the air circuit4170.

In the illustrated example, the plurality of projections16405are structured and arranged to have minimal or no impact on noise (from flow through the opening16105), impedance to air delivery (inlet flow to the patient), and CO2washout (outlet flow to the vent of the elbow assembly16100).

In the nasal interface example, e.g., seeFIGS.42to49, the frame assembly7100includes a shroud7110and a headgear connector7130provided to the shroud7110to provide a 4-point connection to the headgear7800. The shroud7110(e.g., constructed of a relatively hard plastic material such as polycarbonate) includes an opening7105providing an annular edge structured to engage with the elbow assembly7600. The posterior or rear side of the shroud7110includes a plurality of locking tabs or spring arms7125(e.g., 2, 3, 4, 5, or more tabs or spring arms) spaced around the opening7105and structured to provide a mechanical interlock, e.g., snap-fit connection, with the cushion assembly7175.

Upper and Lower Headgear Connectors

The upper headgear connector6130includes a shroud connection portion6132provided to an upper portion of the shroud6110and a pair (i.e., right and left) of rigidised upper headgear connector arms6134(each comprising two flexible portions6140,6145) extending from respective sides of the shroud connection portion6132and structured to connect to respective upper headgear straps of the headgear. The lower headgear connector6150includes a shroud connection portion6152provided to a lower portion of the shroud6110and a pair (i.e., right and left) of lower headgear connector arms6154extending from respective sides of the shroud connection portion6152and structured to connect to respective lower headgear straps of the headgear.

In the illustrated example, each upper headgear connector arm6134includes an upper headgear connection point in the form of a slot6135structured to receive a respective upper headgear strap6802of the headgear. In the illustrated example, each lower headgear connector arm6154includes a lower headgear connection point in the form of a magnetic connector6155structured to locate and connect to a magnet6162associated with a headgear clip6160provided to a respective lower headgear strap6804of the headgear. However, it should be appreciated that the upper and lower headgear connector arms6134,6154may be connected with headgear straps of the headgear in other suitable manners.

Each of the upper headgear connector arms6134is structurally rigid to resist torsion (twisting) and each includes central and peripheral flexible portions6140,6145to conform to varying facial profiles. The central flexible portion6140of each arm6134is positioned proximal to the shroud6110and the shroud connection portion6132. The peripheral flexible portion6145of each arm6134is positioned between the upper headgear connection point6135and the central flexible portion6140. The central flexible portion6140is separated from the peripheral flexible portion6145by a first rigid portion6143. The peripheral flexible portion6145is separated from the upper headgear connection point6135by a second rigid portion6147.

Each upper arm6134extends and curves in an upwards direction between the eyes and ears to avoid obstructing patient's vision, position the headgear attachment point (e.g., slot6135) so that the upper headgear straps extend above and avoid the patient's ears, and provide a force vector that extends generally parallel to the Frankfort horizontal line (e.g., seeFIGS.4and5).

The upper arms6134are also curved (orthogonal to the plane of the face) to conform to the facial profile e.g., the arms curve to generally match the curvature of the cheek bones and avoid load on the temple.

The upper arms6134are rigidised to resist deformation in order to maintain its predetermined shape to ensure the frame assembly6100positions the headgear attachment points in the same position and avoid translating headgear tension forces to compressive forces resulting in uncomfortable facial contact by the upper arms.

The upper arms6134are also rigidised to resist tension forces that may be provided by the headgear straps to prevent twisting of the arms.

In an example, the upper arms are rigidised or stiffened such that that they maintain a preformed 3D shape (not floppy) structured to conform to the facial profile and positions the headgear attachment points in the appropriate locations. Each upper arm maintains its preformed shape due to its rigidity or stiffness in particular orientations. The upper arms are structured to be less resistant (less stiff or rigid) to bending into and away from the face to adapt varying facial widths. The upper arms are rigidised such that they do not substantially deform under tension forces applied by the headgear straps, thereby acting as an intermediary between the headgear straps and the cushion assembly to convert the tension forces from the headgear straps to a compressive force applied on the seal-forming structure to provide seal and stability on the face. The upper arms are also shaped to apply the appropriate force vectors on the seal-forming structure via the shell to effect a stable and comfortable seal. In an example, the seal-forming structure is pulled into the face under the appropriate compressive force that is also in line with the Frankfort horizontal plane (that is pulled directly back into the face).

In an example, the upper arms are rigidised to provide torsional rigidity to be resistant to deformation under twisting. The upper arms are also resistant to bending deformation vertically up and down alongside the face (i.e., remain at the correct height above the ears. However, the upper arms are also structured to provide a predetermined level of deformation to allow bending (allows bending towards/away from the face) to adjust for varying facial width. In addition, the upper arms are resilient/elastic in this orientation to allow the upper arms to return to their original positions. This feature may also prevent discomfort by minimising the load/force exerted by the frame assembly on the face when the headgear straps are tightened by absorbing some of these tension forces due to its flexibility. In some locations, the upper arms may also provide substantially rigidity/stiffness to avoid contact of the face, wherein the arms may act as a strut to resist bending deformation or compression into the face from headgear tension. Conversely, in other locations, the flexibility of the arms may allow the arms to collapse under tension or compression from side load (e.g., when a patient sleeps on their side, thereby exerting a side load on the patient interface. The arms absorb the compressive force applied by the side load and prevent it from dislodging the seal-forming structure. This flexibility also allows for better conformation to the face, which increases comfort and also prevents seal instability from side load.

The central flexible portion6140is configured to allow the respective arm6134to flex to adapt to varying facial width (between patients). For example, for wide faces, the central flexible portion6140allows the arms6134to flex outwardly away from one another and away from the face, and for narrow faces, the central flexible portion6140allows the arms6134to flex towards one another and towards the face. In the illustrated example, the central flexible portion6140of each arm comprises a single slot6141(on an anterior side) forming a hinge.

It should be appreciated that the slot6141may include other suitable arrangements and configurations to modify the location and flexibility characteristics of the arm, e.g., more than one slot, slots on one or both sides of the arm (anterior and/or posterior sides), spacing between slots, width, depth, orientation or angle of slot on the arm. In an example, the slot6141may be filled with a flexible material. In alternative examples, the hinge may be provided by a number of different methods, e.g., such as a thinner cross section or the use of a flexible material joint.

The first and second rigid portions6143,6147provide structural rigidity to the arms6134to support its predetermined shape.

The peripheral flexible portion6145is configured to allow the respective arm6134to conform to the varying curvature or profile of the user's face, e.g., conform to cheek variation between patients. For example, the peripheral flexible portion6145articulates to conform to the width and profile of the cheeks above the cheek bones of the user. In the illustrated example, the peripheral flexible portion6145of each arm6134comprises a plurality of slots6146(on each side of the arm, i.e., slots on anterior and posterior sides of the arm) forming a plurality of hinges over the cheek region. The hinges allow the arms6134to articulate and conform to micro variations of the cheek region and distribute load on the face more evenly upon headgear tension, e.g., when compared to a rigidiser arm without any flex.

In the illustrated example, the slots6146are generally parallel to one another, generally evenly spaced apart from one another, and include similar widths and depths into the thickness of the arm. However, it should be appreciated that the slots6146may include other suitable arrangements and configurations to modify the location and flexibility characteristics of the arm6134, e.g., number of slots, slots on one or both sides of the arm (anterior and/or posterior sides), spacing between slots, width, depth, orientation or angle of slot on the arm (e.g., slots angled relative to one another to provide bending in different orientations). In an example, one or more of the slots6146may be filled with a flexible material. In an alternative example, the hinge may be provided by a plurality of flexible sections (by material) spaced apart by rigid segments.

In alternative examples, it should be appreciated that the upper headgear connector arms6134may include any suitable number of flexible portions along its length to modify its flexibility characteristics, e.g., one, two, three or more flexible portions.

In the illustrated example, to minimise discomfort, the upper arms6134may have a smooth and curved surface profile to distribute load and allow the arms rock over the face without a concentrated load or stabbing into the face. For example, as shown inFIG.26, each upper arm6134may include a generally lozenge-shaped cross-section, e.g., generally flat but slightly dome shape on either side to increase contact comfort.

In an example, the lower headgear connector arms6154are relatively more flexible than the upper headgear connector arms6134, e.g., the lower headgear connector arms6154have less resistance against torsion such that they may twist with the lower headgear straps of the headgear. This flexibility allows the lower arms6154to twist and turn with the lower headgear straps to prevent forced disconnection of the retention features under these forces, i.e., maintain connection of the lower arms with the lower headgear straps.

Each lower arm6154comprises the magnetic connector6155(e.g., encased magnet) structured to locate and connect to the headgear clip6160provided to the respective lower headgear strap of the headgear. The magnetic connector6155also provides a receptacle6156, which allows insertion and retention of a corresponding protrusion (e.g., provided by the magnet6162of the headgear clip6160) to resist disconnection from tension of the headgear straps. The retention allows connection to be maintained while allowing the headgear clip6160to rotate relative to respective lower arm6154. That is, the protrusion/magnet6162of the headgear clip6160and the receptacle6156of the magnetic connector6155include corresponding cylindrical shapes to allow relative rotation. The magnets are used for locating the headgear clip in correct position for retaining engagement via engagement of the protrusion/magnet6162member into the receptacle6156.

The upper and lower arms6134,6154are connected to the shroud6110via the respective shroud connection portion6132,6152. In the illustrated example, the upper and lower arms6134,6154are permanently (e.g., co-molded, overmolded) connected to the shroud6110. As illustrated, each shroud connection portion6134,6154includes a plurality of pins6133,6153that are received in respective openings6113,6114provided to the shroud6110which form rivets to mechanically secure the upper and lower arms6134,6154to the shroud6110after the molding process (e.g., seeFIGS.21,24, and25). In the illustrated example, the shroud6110includes upper and lower grooves6111,6112structured to receive respective shroud connection portions6132,6152of the upper and lower headgear connectors, and the openings6113,6114for securing the upper and lower headgear connectors are provided within the grooves6111,6112(e.g., seeFIGS.24and25). However, it should be appreciated that the upper and lower headgear connector arms6134,6154may be connected to the shroud6110in other suitable manners, e.g., removable connection.

In an example, the upper arms6134and/or the lower arms6154may be covered by a textile, e.g., for aesthetics, increase perception of softness/comfort. For example,FIGS.4and5show a textile arm cover or sock6750provided to the upper arms6134, whileFIGS.6to10, for example, show the upper arms6134with the arm covers6750removed.

The upper and lower arms may provide targeted flexibility in alternative manners. For example, the arms may be formed by a single material with a varying cross sectional thickness for targeted flexibility, e.g., flexible areas may be thinner to provide a living hinge, while thickened areas will have a reduced flexibility. In another example, the arms may be formed by two or more materials, each material having different elastic properties/young's modulus, e.g., rigid sections may be formed in rigid materials such as polycarbonate, while each rigid section may be joined by an intermediary flexible/soft material such as liquid silicone rubber to provide targeted flex. In another example, the arms may be formed in layers of different materials, e.g., the arms may be formed by at least a bendable or flexible first layer. The flexible first layer may provide a substrate surface for multiple rigid portions that are spaced apart to form a second rigid layer. The rigid portions may flex relative to each other, while being supported by the first layer. In an example, the substrate layer in this example has the required stretch properties to provide the required tension forces to the patient interface. In the current example, the substrate layer has minimal to no stretch to prevent the tension forces from being absorbed by the substrate layer.

The arms provide the required stiffness (e.g. resist torsional forces, maintain a preformed shape, etc.) for maintaining the patient interface in the desired position. However, the arms may in some cases provide a reduction in comfort due to the hardness and rigidity of the component (i.e., resistance to conforming to the face). This discomfort is due to a combination of tactile feel and resistance in conforming to facial profile variations, which may provide an undesirable load on sensitive portions of the face. To overcome this aspect, the arms may be coated or covered with a softer and in some cases a less rigid material. The material may act to absorb some or all of the compressive forces applied by the arms on the user's face. Moreover, the soft and/or less rigid material may act to conform to facial profile variations, thereby acting as a conforming layer. In addition, the arm may be coated or covered with a tactile layer may have a desirable tactile feel for direct contact with the user's face. The tactile layer may comprise a desirable fabric with enhanced tactile feel and desirable predetermined stretch characteristics. The arm may further comprise a compliant layer comprising a less rigid and/or soft material such as foam for absorbing the compressive forces applied by the arm on the user's face and/or complying with facial variations by conforming the facial profile.

In an example, both the tactile layer and the compliant layer may be structured or comprise materials that substantially do not alter the function of the arms. That is, the layers should not alter the preformed shape of the arms. Moreover, the layers should allow for the arms to flex/bend in particular orientations as defined. Thus the layers should be structured or comprise selected materials to maintain the function of the arms. Furthermore, the layers may be permanently or semi-permanently fixed to the arms. Alternatively, the arms may comprise a removable layer to cover the arms. For example, the removable layer may be a textile cover or sock. The arm may comprise a superior surface for contact with the user's face. The superior surface may comprise a foam layer above the rigid material, which is subsequently covered by the tactile layer. The arm may also comprise an inferior surface covered by the tactile layer.

There are a number of ways to fix the layers to the arm. In one example, the compliant layer is a foam such as memory foam, which is glued, laminating, moulded, mechanically attached, etc. to the superior surface of the arm. The tactile layer is then attached to the foam compliant layer by laminating, stitching, gluing, etc. the tactile layer to the foam. In an example, in both cases the attachment means should not substantially alter the shape and rigidity of the arms. That is, the attachment means for the layers should not substantially change the flexing/bending of the arms nor change the ability of the arms to maintain its preformed shape.

In the alternative example shown inFIGS.75to100, each upper headgear connector arm16134includes a shroud connection portion16132provided to a respective upper portion of the shroud16110, and each lower headgear connector arm16154includes a shroud connection portion16152provided to a respective lower portion of the shroud16110.

In the illustrated example, each upper headgear connector arm16134includes an upper headgear connection point in the form of a slot16135structured to receive a respective upper headgear strap16802of the headgear. As best shown inFIG.104, the bridge or cross-bar16136defining the slot16135includes a leading edge16136A that is tapered (e.g., like a knife edge) to facilitate assembly/disassembly to the upper headgear strap16802of the headgear. For example, the tapered leading edge16136A may readily slide through and between the Velcro™-like hook tab16803and the remainder of the upper headgear strap16802to facilitate assembly/disassembly without fully releasing the Velcro™-like hook tab16803from the remainder of the upper headgear strap16802. In the illustrated example, each lower headgear connector arm16154includes a lower headgear connection point in the form of a magnetic connector16155structured to locate and connect to a magnet associated with a headgear clip16160provided to a respective lower headgear strap16804of the headgear. However, it should be appreciated that the upper and lower headgear connector arms16134,16154may be connected with headgear straps of the headgear in other suitable manners.

Similar to the upper headgear connector arms described above, each of the upper headgear connector arms16134is structurally rigid to resist torsion (twisting) and each includes central and peripheral flexible portions16140,16145to conform to varying facial profiles. The central flexible portion16140(i.e., the first flexible portion) of each arm16134is positioned proximal to the shroud connection portion16132. The peripheral flexible portion16145(i.e., the second flexible portion) of each arm16134is positioned between the upper headgear connection point16135and the central flexible portion16140.

In the illustrated example, the central flexible portion16140of each arm16134comprises a single slot16141(on a posterior side) forming a hinge. In the illustrated example, the peripheral flexible portion16145of each arm16134comprises a plurality of slots16146(on each side of the arm, i.e., slots on anterior and/or posterior sides of the arm) forming a plurality of hinges over the cheek region.

In examples, the peripheral flexible portion16145of each arm need not include slots on the anterior or posterior sides. Instead, or in addition, the flexible portion may include one or more interconnecting elastomeric (e.g., silicone) sections that may form a flush or smooth transition between relatively harder plastic sections, but allow flexing, bending and/or pivoting. These can be made via insert or over molding, where the harder plastic sections are placed in the mold and the interconnecting sections are molded over the harder plastic sections.

Each lower headgear connector arm16154comprises the magnetic connector16155(including encased magnet16155B) structured to locate and connect to the headgear clip16160(including encased magnet16162) provided to the respective lower headgear strap of the headgear, e.g., seeFIG.103. In the illustrated example, the end of each lower arm16154includes a magnet receiving portion16155A to receive and align a magnet16155B and a cap16155C to enclose and retain the magnet16155B to the magnet receiving portion16155A. As illustrated, the magnetic connector16155provides a protrusion which allows it to be inserted and retained within a corresponding receptacle provided by the headgear clip16160, e.g., seeFIG.103. The headgear clip16160includes a catch or retaining wall16164that resists disconnection from tension of the headgear straps while allowing the headgear clip16160to rotate (e.g., allow for 360° rotation) relative to respective lower arm16154. In the illustrated example, as shown inFIGS.101,102, and103, the catch or retaining wall16164(e.g., semi-circular cross-section or U-shape) provides a mechanical retention member to mechanically engage with a semi-circular peripheral region of the connector16155. In an example, the magnetic connector16155and/or the catch or retaining wall16164may be angled or sloped to provide an undercut to facilitate retention of the headgear clip16160on the magnetic connector16155.

In an example, as shown inFIG.96, each lower headgear connector arm16154and magnetic connector16155thereof may be manufactured by molding the cap16155C, assembling the magnet16155B in the cap16155C, inserting the assembled cap/magnet in a lower arm molding tool, and then molding the lower arm16154to the cap/magnet. In an example, the cap16155C may include an orientation feature, e.g., slot16159, to facilitate correct orientation and alignment of the cap16155C relative to the lower arm16154.

In an alternative example, as shown inFIG.97, each lower headgear connector arm16154and magnetic connector16155thereof may be manufactured by molding the lower arm16154, assembling the magnet16155B in the magnet receiving portion16155A of the lower arm16154, inserting the assembled lower arm/magnet in a cap molding tool, and then overmolding the cap16155C to the lower arm/magnet.

In the illustrated example, each lower headgear connector arm16154comprises a single slot16156(on a posterior side) forming a hinge portion, e.g., seeFIGS.75and76. This hinging portion is structured and arranged to accommodate for facial width variation by allowing the lower arms16154to flex away from the patient's face in use, e.g., allows easy adjustment during initial fitting of the patient interface and allows adaption to various facial geometry without affecting seal of the patient interface. Also, the hinging portion allows the lower arms16154to move or flex with corresponding headgear clips16160in use, e.g., to prevent inadvertent detachment of the headgear clip16160from the respective magnetic connector16155.

The upper and lower arms16134,16154are connected to the shroud16110via the respective shroud connection portion16132,16152. In the illustrated example, the upper and lower arms16134,16154are permanently connected (e.g., ultrasonically welded) to the shroud16110.

As shown inFIGS.83to86, the shroud16110includes a pair (i.e., right and left) of upper anchors or upper arm connectors16450on respective sides of an upper portion of the shroud16110, and a pair (i.e., right and left) of lower anchors or lower arm connectors16460on respective sides of a lower portion of the shroud16110. Each upper anchor16450provides an opening16452and each lower anchor16460provides an opening16462.

As shown inFIGS.90and91, the shroud connection portion16152of each lower arm16154includes a protrusion16153that is received in the opening16462of a respective lower anchor16460. The protrusion16153includes an opening16153A that receives a protrusion16158provided to a cap16157which engages and interlocks the shroud connection portion16152to the cap16157. The shroud connection portion16152and the cap16157are ultrasonically welded to mechanically secure the shroud connection portion16152to the cap16157, thereby securing the lower arm16154to the lower anchor16460.

In the illustrated example, the caps16157are symmetrical to facilitate manufacturing and assembly. However, it should be appreciated that the caps for secruing the lower arms may be assymetrical. For example,FIGS.92to95show an alternative arrangement in which lower arms17154are secured to the shroud17110with respective asymmetrical caps17157.

Similarly, as shown inFIGS.99and100, the shroud connection portion16132of each upper arm16134includes a protrusion16133that is received in the opening16452of a respective upper anchor16450. The protrusion16133includes an opening16133A that receives a protrusion16138provided to a cap16137which engages and interlocks the shroud connection portion16132to the cap16137. The shroud connection portion16132and the cap16137are ultrasonically welded to mechanically secure the shroud connection portion16132to the cap16137, thereby securing the upper arm16134to the upper anchor16450

However, it should be appreciated that the upper and lower headgear connector arms16134,16154may be connected to the shroud16110in other suitable manners, e.g., removable connection. For example,FIG.98illustrates a connector arm17134connected to an anchor17450via a snap joint, e.g., push through snap joint arrangement including pegs structured to engage within respective openings with a snap fit.

In an example, the upper and/or lower anchors16450,16460of the shroud16110may be structured to enhance robustness. For example, the sharp corners along the anchor may be eliminated to reduce stress concentration, e.g., edges along the opening of the anchor may be rounded (e.g., seeFIG.87). Also, the bridge member of the anchor may be provided with an increased thickness to increase section strength, e.g., see bridge member16454of upper anchor16450inFIG.87. In addition, ribs may be provided to arms of the anchor to increase strength, e.g., see ribs16456provided to arms of upper anchor16450inFIG.87.

In an example, the upper arms16134and/or the lower arms16154may be covered by a textile, e.g., for aesthetics, increase perception of softness/comfort, provide comfort on the face and minimise marking. For example,FIGS.59to61show a textile arm cover or sock16750provided to the upper arms16134, whileFIGS.62to65, for example, show the upper arms16134with the arm covers16750removed. The cover16750conceals the upper arms16134making the outer surface smooth to increase comfort on the face, e.g., no marking and easier to slide over the facial surface. The cover16750may be optionally removable.

In an example, at least a portion of the upper arms16134and/or the lower arms16154may include dimples or a gold ball pattern, e.g., for aesthetics.

In the nasal interface example, e.g., seeFIGS.42to49, the headgear connector7130includes a shroud connection portion7132connected to the shroud7110, a pair (i.e., right and left) of upper headgear connector arms7134structured to connect to respective upper headgear straps7802of the headgear7800, a pair (i.e., right and left) of lower headgear connector arms7154structured to connect to respective lower headgear straps7804of the headgear7800, and intermediate portions7133to interconnect the upper and lower arms7134,7154with the shroud connection portion7132.

In the illustrated example, each upper headgear connector arm7134includes an upper headgear connection point in the form of a slot7135structured to receive a respective upper headgear strap7802of the headgear7800(seeFIG.29). In the illustrated example, each lower headgear connector arm7154includes a lower headgear connection point in the form of a magnetic connector7155structured to locate and connect to a magnet associated with a headgear clip7160provided to a respective lower headgear strap7804of the headgear7800(seeFIG.29). However, it should be appreciated that the upper and lower headgear connector arms7134,7154may be connected with headgear straps of the headgear in other suitable manners.

Similar to the above example, each intermediate portion7133of the headgear connector7130assembly includes a flexible portion7140to conform to varying facial profiles, e.g., accommodate facial width variations. In the illustrated example, the flexible portion7140comprises a single slot (on anterior and/or posterior sides) forming a hinging section adjacent the cushion assembly.

As shown inFIGS.48and49, the headgear connector7130may include a multi-layered configuration, e.g., layers of different materials to provided desired flexibility.

Cushion Assembly

In one form of the present technology, the cushion assembly or cushion module6175includes a main body, chassis, or shell6180that is connected or otherwise provided to the seal-forming structure or cushion6200(seeFIGS.15and16). The shell6180may be permanently (e.g., co-molded, overmolded) or removably (e.g., mechanical interlock) connected to the cushion6200. In an example, the cushion6200is constructed of a relatively flexible or pliable material (e.g., silicone) and the shell6180is constructed of a relatively rigid material (e.g., polycarbonate). The shell6180and the cushion6200cooperate to form the plenum chamber6500.

The shell6180includes an opening6305by which breathable gas is delivered to the plenum chamber6500. The opening6305is bounded by an annular flange6310which is adapted to be connected to the frame assembly6100and adapted to interface (e.g., seal) with the elbow assembly6600which is connected to the gas delivery tube4180.

The shell6180has multiple functions. For example, it forms the plenum chamber for delivery of pressurised gases to the entrance of a patient's airways. The shell6180is a rigid structure that directs a force onto the seal-forming structure for sealing to a patients face. The force is provided by tension forces from tightening the headgear straps. These forces are translated from a pair of upper and lower headgear straps to the corresponding upper and lower arms. In an example, the upper and lower arms are provided the frame assembly, which provides the headgear tension forces to the shell6180.

The shell6180also provides an outer (or anterior) surface for engaging the inner (or posterior) surface of the shroud of the frame assembly to effect a seal. The shell also comprises separate retention features or is otherwise structured to detachably engage to the inner surface of the frame assembly. The patient interface is modular in that a single frame assembly size is capable of connection to multiple cushion assembly sizes (e.g., small to large). Thus, the shell also detachably engages to the frame assembly such that the frame assembly is connected into a predetermined configuration that corresponds to its respective cushion assembly size. For example, smaller cushion assemblies have an overall reduced height relative to medium or large cushion assemblies. Thus the frame assembly connects in a position relative to the cushion assembly to position the upper headgear attachment point in their correct position (between the eyes and ears, while providing an attachment point where the upper headgear straps avoid the ears). This means that the frame assembly connects at a higher position on the shell when compared to medium or large cushion assembly sizes. In an example, medium and/or large sizes may not have this requirement and connect such that the frame assembly is positioned in substantially the same position.

In the alternative example shown inFIGS.75to100, the cushion assembly16175includes shell16180that is connected or otherwise provided to the seal-forming structure or cushion16200(seeFIGS.73and74). The shell16180and the cushion16200cooperate to form the plenum chamber16500(e.g., seeFIGS.69and71). The shell16180includes an opening16305by which breathable gas is delivered to the plenum chamber16500. The opening16305is bounded by an annular flange16310which is adapted to connect to the frame assembly16100.

In the nasal interface example, e.g., seeFIGS.39to41, the cushion assembly7175includes a shell7180that is permanently (e.g., co-molded, overmolded) connected to the seal-forming structure or cushion7200. In an example, the cushion7200is constructed of a relatively flexible or pliable material (e.g., silicone) and the shell7180is constructed of a relatively rigid material (e.g., polycarbonate). The shell7180and the cushion7200cooperate to form the plenum chamber7500. In the illustrated example, the flexible flange or lip seal7250(i.e. seal7250provides a seal with the elbow assembly7600) is provided in one-piece with the cushion7200, e.g., connecting portion7149interconnects seal7250and cushion7200as shown inFIGS.38and39.

Connection Between Cushion Assembly and Frame Assembly

In one form of the present technology, the shell6180of the cushion assembly6175is repeatedly engageable with and removably disengageable from the shroud6110of the frame assembly6100via a mechanical interlock, e.g., snap-fit connection.

The cushion assembly6175and the frame assembly6100include cooperating retaining structures to connect the cushion assembly6175to the frame assembly6100. In an example, the frame assembly6100is releasably connectable to the cushion assembly6175to facilitate replacement and/or cleaning, and to allow alternative frame assemblies and cushion assemblies to be connected to one another. Such arrangement allows multiple seals (e.g., types and sizes) to be used with the patient interface and therefore provide a patient interface suitable for Multiple Patient Multiple Use (MPMU) usage situations. In an alternative example, the frame assembly6100may be permanently connected or integrally formed in one-piece with the cushion assembly6175, e.g., co-molded

In the illustrated example, the shell6180includes an opening6305bounded by an annular flange6310that protrudes forwardly from the shell6180. The flange6310includes a plurality of tabs or catches6315along its perimeter (e.g., seeFIGS.15and17), e.g., 3, 4, 5 or more tabs, which are structured to engage or interlock with corresponding spring arms6125on the posterior side of the shroud6110, e.g., with a snap-fit, to releasably connect the cushion assembly6175to the frame assembly6100.

The cushion assembly6175also includes one or more recesses6320(e.g., seeFIGS.15and17) along the perimeter of the flange6310(e.g., upper and lower recesses) structured to engage or interlock with corresponding protrusions6127on the posterior side of the shroud6110, e.g., to facilitate alignment, prevent relative rotation.

In the illustrated example, the shell6180of the cushion assembly6175and the shroud6110of the frame assembly6100are relatively rigid (e.g., both formed of a relatively hard material, e.g., such as polycarbonate) such that engagement between the shell6180and the shroud6110provides a hard-to-hard connection. Also, the perimeter, shape, and geometry of the mating surfaces provided by the shell6180and the shroud6110are predetermined to facilitate alignment and mechanical/structural engagement, e.g., clean, smooth, curved mating surfaces. That is, the relative rigidity or stiffness of the shroud and the shell are to maintain the preformed structure of the components. The stiffness allows for the components to maintain their shape so that they may be easily aligned for connection.

It should be appreciated that the cushion assembly may be connected or interlocked with the frame assembly in other suitable manners. For example, these components may be connected via a clip.

In the alternative example, as best shown inFIGS.70and72, the inner annular flange16125of the shroud16110extends through the opening16305of the shell16180, and the tabs or catches16127of the flange16125engage or interlock on a posterior side of the annular flange16310of the shell16180so as to releasably connect the frame assembly16100to the cushion assembly16175. Such connection maintains ease of use, provides a sealed hard to hard connection, minimizes rattling and rocking movement between components, and reduces impact on stability. Also, such connection stably holds the cushion assembly16175in position, while allowing the appropriate force vectors to be imparted onto the cushion assembly16175for seal.

Also, the frame assembly16100is structured to form a static diametric seal and a static face seal with the cushion assembly16175to minimize and control leak. As illustrated inFIGS.70and72, the shroud16110of the frame assembly16100includes a channel adapted to receive the flange16310of the cushion assembly16175. The leading edge16310A of the flange16310and the end wall16112A of the channel are configured and arranged to provide a static face seal, and the outer side16310B of the flange16310and the side wall16112B of the channel are configured and arranged to provide a static diametric seal.

In the nasal interface example, e.g., seeFIGS.30to49, the shell7180includes a plurality of tabs or catches7315along the perimeter of flange7310, which are structured to engage or interlock with corresponding tabs or arms7125on the posterior side of the shroud7110, e.g., with a snap-fit, to releasably connect the cushion assembly7175to the frame assembly7100.

The cushion assembly7175also includes one or more recesses7320(e.g., seeFIG.41) along the perimeter of the flange7310(e.g., lower recess) structured to engage or interlock with corresponding protrusions7127(e.g., seeFIG.43) on the posterior side of the shroud7110, e.g., to facilitate alignment, prevent relative rotation.

In another example, as shown inFIGS.55to58, the shell of the cushion assembly8175may include a central aperture with an internal surface structured to receive an annular central flange of the frame assembly8100. The shell includes a retention feature that interlocks or connects to a retention feature on the frame assembly. In addition, a clearance is maintained within the aperture of the shell for a bellows structure8250of a vent adaptor8900(FIGS.55and56) or elbow assembly8600(FIGS.57and58) to engage with a surface8275of the shell to effect a face seal.

The cushion assembly6175and the frame assembly6100are structured to maintain engagement during use and prevent any unintentional or partial disassembly during use.

In one form of the present technology, the frame assembly6100is engageable with the cushion assembly6175by posteriorly moving the frame assembly6100towards the cushion assembly6175in a direction substantially parallel to the Frankfort horizontal, and the frame assembly6100is disengageable from the cushion assembly6175by anteriorly moving the frame assembly6100from the cushion assembly6175in a direction substantially parallel to the Frankfort horizontal.

Elbow Assembly

As shown inFIGS.27and28, the elbow assembly6600includes a first end portion6610that is repeatedly engageable with and removably disengageable from the shroud6110of the frame assembly6100and a second end portion6620adapted to connect to the air circuit4170, e.g., via a swivel connector6625.

The first end portion6610includes a pair of resilient, quick release pinch arms6650, i.e., cantilevered spring arm. Each of the spring or pinch arms6650includes a barbed end or tab6652structured to provide a mechanical interlock, e.g., snap-fit connection, with the flange6115of the shroud6110.

The first end portion6610includes an annular side wall6630structured to extend through the frame assembly6100and form a seal with the cushion assembly6175.

In the illustrated example, a vent6700is integrated into the first end portion6610to allow for the washout of exhaled air, e.g., vent exits of the vent provided along a perimeter of the first end portion6610.

In the alternative example, as best shown inFIGS.59,65,70, and72, the elbow assembly16600includes a first end portion16610with pinch arms16650to releasably engage with the frame assembly16100and a second end portion16620adapted to connect to the air circuit4170, e.g., via a swivel connector16625.

In this example, the first end portion16610includes inner and outer radial walls16630,16640defining a radial channel16645leading to a plurality of vent holes16700to permit the exit of exhausted gases from the patient interface.

In addition, the elbow assembly16600is structured to house an AAV assembly including AAVs structured to allow the patient to breathe through ports if pressurized gas is not of sufficient magnitude or not delivered.

FIGS.50and51show the elbow assembly7600structured for connection to the nasal type patient interface7000.FIGS.52and53show an alternative elbow assembly9600structured for connection to the nasal type patient interface7000.

In the illustrated examples, each side of the elbow assembly7600,9600includes a cantilevered push button and grooves along sides of the push button that allow the push button to flex. Each push button includes a tab or catch that is adapted to engage the edge of the opening7105of the frame assembly7100with a snap fit to releasably secure the elbow assembly7600,9600to the frame assembly7100.

As best shown inFIGS.51and53, a raised portion of the button and webbing within the grooves along sides of the button is constructed of a soft, tactile material, e.g., TPE. The raised portion provides a soft tactile feel for ease of use and grip, and the webbing provides seal, soft tactile feel, and spring (clip return) force. In an example, the raised portion and webbing are overmolded to the main elbow body including the push buttons.

As shown inFIGS.50and51, the elbow assembly7600includes a vent assembly7700to allow for the washout of exhaled air.

Connection Between Elbow Assembly and Frame Assembly

The elbow assembly6600releasably connects and retains onto the frame assembly6100via the pinch arms6650, e.g., quick release snap-fit. The flange6115of the shroud6110defines the circular channel6120which is structured to receive the barbed end6652of the pinch arms6650to releasably retain the elbow assembly6600to the frame assembly6100and form a swivel connection (e.g., seeFIG.6), e.g., allow 360° free rotation of the elbow assembly6600relative to the frame assembly6100.

Because the elbow assembly6600connects to the frame assembly6100independently of the cushion assembly6175, the patient is able to remove and swap different size cushion assemblies without the need for disconnecting the elbow assembly6600, frame assembly6100, and headgear.

Similarly, in the alternative example as best shown inFIG.72, the circular channel16120of the frame assembly16100is structured to receive the barbed end16652of the pinch arms16650to releasably retain the elbow assembly16600to the frame assembly16100.

Seal Between Elbow Assembly and Cushion Assembly

In an example, the cushion assembly6175comprises a flexible flange or lip seal6250to provide a seal with the elbow assembly6600. The lip seal6250is provided to the flange6310of the shell6180and includes a free end that extends radially inwardly into the opening6305. As shown inFIGS.13and14, the elbow assembly6600is structured to mechanically interlock with the frame assembly6100, but is structured and arranged to sealingly engage with sealing membrane6250of the cushion assembly6175to form a seal for the air flow path, i.e., sealing mechanism is separate from the retention features.

As illustrated, the leading edge of the side wall6630of the elbow assembly6600forms a face seal with the lip seal6250. This form of engagement minimises surface area contact to reduce friction, thereby allowing a seal to form between the components while allowing the elbow assembly6600to swivel freely relative to the frame and cushion assemblies6100,6175.

In the nasal interface example, e.g., seeFIGS.37and38, the elbow assembly7600is structured to mechanically interlock with the frame assembly7100, and the leading edge of the side wall7630of the elbow assembly7600is structured and arranged to sealingly engage with the lip seal7250of the cushion assembly7175to form a seal for the air flow path.

Seal Between Elbow Assembly and Frame Assembly

In an alternative example, the elbow assembly16600is structured to establish a hard-to-hard connection and seal with the frame assembly16100. As best shown inFIG.72, a dynamic diametric seal is formed between the cylindrical outer surface of the outer wall16640of the elbow assembly16600and the inner surface provided by the annular flanges16115,16125of the frame assembly16100. Also, the annular flange16125of the frame assembly16100comprises the radially inwardly extending ridge16400that acts as a stop to prevent over-insertion of the elbow assembly16600into the frame assembly16100. The surface of the ridge16400also provides a dynamic face seal with the leading edge or surface of the outer wall16640of the elbow assembly16600. The diametric seal and the face seal provided between surfaces of the outer wall16640and surfaces of the annular flanges16115,16125/ridge16400provide two mating surfaces of contact between the elbow assembly16600and the frame assembly16100, which increases the surface area of contact between the elbow assembly16600and the frame assembly16100. The two mating surfaces are configured and arranged to minimize and control leak by providing a tortuous leak path, i.e., leak path between the two mating surfaces extends radially to axially from interior the patient interface to atmosphere.

Lockout Feature

As noted above, the ridge16400of the frame assembly16100includes a plurality of projections16405structured to provide a lockout feature to prevent direct connection or insertion of the air circuit4170to the frame assembly16100.

As best shown inFIG.72, each projection16405extends to the inner wall16630of the elbow assembly so that the projections16405do not extend significantly into the inlet flow path to the patient. In addition, each projection16405includes an opening16407(e.g., seeFIGS.72,83, and88) so the projections16405do not significantly block outlet flow to the channel16645leading to the vent holes16700of the elbow assembly16100. Thus, the plurality of projections16405are structured and arranged to have minimal or no impact on noise (from flow through the opening16105), impedance to air delivery (inlet flow to the patient), and CO2washout (outlet flow to the vent of the elbow assembly16100.

In an alternative example, as shown inFIG.89A, each of the projections16405may be provided without an opening.

In another alternative, as shown inFIG.89B, the lockout feature may be provided by a single annular projection16405that extends along the entire perimeter of the ridge16400. As illustrated, openings16407are provided along the projection16405, e.g., so the projection16405does not significantly block outlet flow to the channel16645leading to the vent holes16700.

Vent Adaptor Connector

In an alternative example, a vent adaptor connector may be provided to the patient interface, e.g., as an alternative to the elbow assembly6600. Similar to the arrangement described above, the vent adaptor connector may be releasably connected to the frame assembly6100independent of the cushion assembly6175, and may sealingly engage with the sealing membrane6250of the cushion assembly6175to form a seal for the air flow path.

Alternative Connection/Seal of Elbow Assembly/Vent Adaptor Connector

As aforementioned, the patient interface is connectable to both an elbow assembly and a vent adaptor connector, e.g., elbow assembly/vent adaptor connector releasably connected to the frame assembly and sealingly engaged with the cushion assembly.

In an alternative example, as shown inFIGS.55to58, the elbow assembly8600/vent adaptor connector8900includes a seal or bellows structure8250(e.g., formed of silicone) structured to engage an inner surface8275provided to the shell of the cushion assembly8175. The bellows structure is structured to move towards the inner surface of the shell when pressure is increased within the components, i.e., pressure supported seal. The bellows structure engages with the inner surface on the shell along the inlet opening to provide a bellows face seal.

The seal forming structures of the vent adaptor connector/elbow assembly and the shell are separate to the retention forming features. In an example, the frame comprises a retention feature including a resilient pair of arms adapted for insertion into corresponding grooves in the vent adaptor connector/elbow assembly. The connection is also a swivel connection allowing the vent adaptor connector/elbow assembly to swivel relative to the cushion assembly and frame assembly. Hence, the bellows face seal has another advantage in that it effects a seal between the components with minimal friction to allow substantial relative movement without breaking seal. In an example, the frame assembly is structured such that it does not form part of the air delivery path to the patient but is structured to removably retain both the cushion assembly and vent adaptor connector/elbow assembly in position. The vent adaptor connector/elbow assembly forms a seal directly with the shell of the cushion assembly through an aperture provided in the frame assembly.

This configuration allows a user to remove the vent adaptor connector/elbow assembly from the patient interface, without the need for disconnecting the frame assembly from the cushion assembly, i.e., the patient can stop therapy but leave the patient interface on the face. This configuration also allows a user to remove the cushion assembly from the frame assembly and vent adaptor connector/elbow assembly without the need for disconnecting the frame assembly from the vent adaptor connector/elbow assembly. In an example, the frame assembly is connected to the headgear, thus the headgear can remain connected to the frame assembly and vent adaptor connector/elbow assembly while the user tries various cushion assembly sizes (e.g., small, medium, large) without the need to reassemble multiple components.

Modularity

In the illustrated example, the frame assembly6100may be provided in one size (i.e., common frame assembly), which may be selectively engageable with multiple sizes of cushion assemblies6175, e.g., small, medium, and large size cushion assemblies distinguished by volume/footprint on the patient's face. Thus, the patient has the freedom to change cushion sizes freely without the need to replace the frame assembly6100. In an example, regardless of size, the patient interface provides similar locations for the headgear connectors (e.g., based on headgear vectors and clearance with the patient's eyes) and the connection for the elbow assembly (e.g., to optimize gas washout).

In such example, the shell of each of the different size cushion assemblies includes a connector (annular flange-type connector) that is common or similar for all sizes (e.g., common retention feature), which allows the one size or common frame assembly to be connected to each of the different size cushion assemblies, i.e., each cushion assembly includes a common frame retention feature on the shell for all cushion sizes.

Similar to the above, the frame assembly7100of the nasal interface type may be provided in one size (i.e., common frame assembly), which may be selectively engageable with multiple sizes of cushion assemblies7175, e.g., small, medium, and large size cushion. For example,FIGS.54A,54B, and54Care rear views of small, medium, and large cushion assemblies7175according to an example of the present technology. As illustrated, each size provides a different volume or footprint on the patient's face.

5.3.1 Seal-Forming Structure

In one form of the present technology, a seal-forming structure provides a seal-forming surface, and may additionally provide a cushioning function.

A seal-forming structure in accordance with the present technology may be constructed from a soft, flexible, resilient material such as silicone. In an alternative example, the seal-forming structure may include a foam cushion including a foam seal forming portion. In such example, such foam cushion may be provided to a shell to allow connection to the frame assembly6100.

In one form, the seal-forming structure comprises a sealing flange and a support flange. The sealing flange comprises a relatively thin member with a thickness of less than about 1 mm, for example about 0.25 mm to about 0.45 mm, that extends around the perimeter of the plenum chamber. Support flange may be relatively thicker than the sealing flange. The support flange is disposed between the sealing flange and the marginal edge of the plenum chamber, and extends at least part of the way around the perimeter. The support flange is or includes a spring-like element and functions to support the sealing flange from buckling in use. In use the sealing flange can readily respond to system pressure in the plenum chamber acting on its underside to urge it into tight sealing engagement with the face.

In one form the seal-forming portion of the non-invasive patient interface comprises 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.

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 frusto-cone and connecting the frusto-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 movement both displacement and angular of 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.

In one form, the non-invasive patient interface comprises 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.

In one form the non-invasive patient interface comprises a seal-forming portion that forms a seal in use on a chin-region of the patient's face.

In certain forms of the present technology, a seal-forming structure is configured to correspond to a particular size of head and/or shape of face. For example one form of a seal-forming structure is suitable for a large sized head, but not a small sized head. In another example, a form of seal-forming structure is suitable for a small sized head, but not a large sized head.

5.3.2 Plenum Chamber

The plenum chamber has a perimeter 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 of the plenum chamber is positioned in close proximity to an adjacent surface of the face. Actual contact with the face is provided by the seal-forming structure. The seal-forming structure may extend in use about the entire perimeter of the plenum chamber.

5.3.3 Positioning and Stabilising Structure

The seal-forming structure of the patient interface of the present technology may be held in sealing position in use by the positioning and stabilising structure.

In one form of the present technology, a positioning and stabilising structure is provided that is configured in a manner consistent with being worn by a patient while sleeping. In one example the positioning and stabilising structure has a low profile, or cross-sectional thickness, to reduce the perceived or actual bulk of the apparatus. In one example, the positioning and stabilising structure comprises at least one strap having a rectangular cross-section. In one example the positioning and stabilising structure comprises at least one flat strap.

In one form of the present technology, a positioning and stabilising structure3300comprises a strap constructed from a laminate of a fabric patient-contacting layer, a foam inner layer and a fabric outer layer. In one form, the foam is porous to allow moisture, (e.g., sweat), to pass through the strap. In one form, the fabric outer layer comprises loop material to engage with a hook material portion.

In certain forms of the present technology, a positioning and stabilising structure comprises a strap that is extensible, e.g. resiliently extensible. For example the strap may be configured in use to be in tension, and to direct a force to draw a cushion into sealing contact with a portion of a patient's face. In an example the strap may be configured as a tie.

In certain forms of the present technology, a positioning and stabilising structure comprises a strap that is bendable and e.g. non-rigid. An advantage of this aspect is that the strap is more comfortable for a patient to lie upon while the patient is sleeping.

In certain forms of the present technology, a positioning and stabilizing structure provides a retaining force configured to correspond to a particular size of head and/or shape of face. For example one form of positioning and stabilizing structure provides a retaining force suitable for a large sized head, but not a small sized head. In another example, a form of positioning and stabilizing structure provides a retaining force suitable for a small sized head, but not a large sized head.

5.3.4 Vent

In one form, the patient interface includes a vent constructed and arranged to allow for the washout of exhaled gases, e.g. 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.

The vent may be located in the plenum chamber. Alternatively, the vent is located in a decoupling structure, e.g., a swivel.

5.3.5 Decoupling Structure(s)

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

5.3.6 Connection Port

Connection port allows for connection to the air circuit.

5.3.7 Forehead Support

In the illustrated example, the frame assembly6100is provided without a forehead support.

In another form, the patient interface may include a forehead support, e.g., the frame assembly may include a forehead support.

5.3.8 Anti-Asphyxia Valve

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

5.3.9 Ports

In one form of the present technology, a patient interface 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.

5.4 Glossary

For the purposes of the present technology disclosure, in certain forms of the present technology, one or more of the following definitions may apply. In other forms of the present technology, alternative definitions may apply.

5.4.1 General

Air: In certain forms of the present technology, air may be taken to mean atmospheric air, and in other forms of the present technology air may be taken to mean some other combination of breathable gases, e.g. atmospheric air enriched with oxygen.

Ambient: In certain forms of the present technology, the term ambient will be taken to mean (i) external of the treatment system or patient, and (ii) immediately surrounding the treatment system or patient.

For example, ambient humidity with respect to a humidifier may be the humidity of air immediately surrounding the humidifier, e.g. the humidity in the room where a patient is sleeping. Such ambient humidity may be different to the humidity outside the room where a patient is sleeping.

In another example, ambientpressuremay be the pressure immediately surrounding or external to the body.

In certain forms, ambient (e.g., acoustic) noise may be considered to be the background noise level in the room where a patient is located, other than for example, noise generated by an RPT device or emanating from a mask or patient interface. Ambient noise may be generated by sources outside the room.

Automatic Positive Airway Pressure (APAP) therapy: CPAP therapy in which the treatment pressure is automatically adjustable, e.g. from breath to breath, between minimum and maximum limits, depending on the presence or absence of indications of SDB events.

Continuous Positive Airway Pressure (CPAP) therapy: Respiratory pressure therapy in which the treatment pressure is approximately constant through a respiratory cycle of a patient. In some forms, the pressure at the entrance to the airways will be slightly higher during exhalation, and slightly lower during inhalation. In some forms, the pressure will vary between different respiratory cycles of the patient, for example, being increased in response to detection of indications of partial upper airway obstruction, and decreased in the absence of indications of partial upper airway obstruction.

Flow rate: The volume (or mass) of air delivered per unit time. Flow rate may refer to an instantaneous quantity. In some cases, a reference to flow rate will be a reference to a scalar quantity, namely a quantity having magnitude only. In other cases, a reference to flow rate will be a reference to a vector quantity, namely a quantity having both magnitude and direction. Flow rate may be given the symbol Q. ‘Flow rate’ is sometimes shortened to simply ‘flow’.

In the example of patient respiration, a flow rate may be nominally positive for the inspiratory portion of a breathing cycle of a patient, and hence negative for the expiratory portion of the breathing cycle of a patient. Total flow rate, Qt, is the flow rate of air leaving the RPT device. Vent flow rate, Qv, is the flow rate of air leaving a vent to allow washout of exhaled gases. Leak flow rate, Ql, is the flow rate of leak from a patient interface system or elsewhere. Respiratory flow rate, Qr, is the flow rate of air that is received into the patient's respiratory system.

Leak: The word leak will be taken to be an unintended flow of air. In one example, leak may occur as the result of an incomplete seal between a mask and a patient's face. In another example leak may occur in a swivel elbow to the ambient.

Noise, conducted (acoustic): Conducted noise in the present document refers to noise which is carried to the patient by the pneumatic path, such as the air circuit and the patient interface as well as the air therein. In one form, conducted noise may be quantified by measuring sound pressure levels at the end of an air circuit.

Noise, radiated (acoustic): Radiated noise in the present document refers to noise which is carried to the patient by the ambient air. In one form, radiated noise may be quantified by measuring sound power/pressure levels of the object in question according to ISO 3744.

Noise, vent (acoustic): Vent noise in the present document refers to noise which is generated by the flow of air through any vents such as vent holes of the patient interface.

Patient: A person, whether or not they are suffering from a respiratory disease.

Pressure: Force per unit area. Pressure may be expressed in a range of units, including cmH2O, g-f/cm2and hectopascal. 1 cmH2O is equal to 1 g-f/cm2and is approximately 0.98 hectopascal. In this specification, unless otherwise stated, pressure is given in units of cmH2O.

The pressure in the patient interface is given the symbol Pm, while the treatment pressure, which represents a target value to be achieved by the mask pressure Pm at the current instant of time, is given the symbol Pt.

Respiratory Pressure Therapy (RPT): The application of a supply of air to an entrance to the airways at a treatment pressure that is typically positive with respect to atmosphere.

Ventilator: A mechanical device that provides pressure support to a patient to perform some or all of the work of breathing.

5.4.1.1 Materials

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, an exemplary 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.

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

5.4.1.2 Mechanical Properties

Resilience: Ability of a material to absorb energy when deformed elastically and to release the energy upon unloading.‘Resilient’: Will release substantially all of the energy when unloaded. Includes e.g. certain silicones, and thermoplastic elastomers.

Hardness: The ability of a material per se to resist deformation (e.g. described by a Young's Modulus, or an indentation hardness scale measured on a standardised sample size).‘Soft’ materials may include silicone or thermo-plastic elastomer (TPE), and may, e.g. readily deform under finger pressure.‘Hard’ materials may include polycarbonate, polypropylene, steel or aluminium, and may not e.g. readily deform under finger pressure.

Stiffness (or rigidity) of a structure or component: The ability of the structure or component to resist deformation in response to an applied load. The load may be a force or a moment, e.g. compression, tension, bending or torsion. The structure or component may offer different resistances in different directions.‘Floppy’ structure or component: A structure or component that will change shape, e.g. bend, when caused to support its own weight, within a relatively short period of time such as 1 second.‘Rigid’ structure or component: A structure or component that will not substantially change shape when subject to the loads typically encountered in use. An example of such a use may be setting up and maintaining a patient interface in sealing relationship with an entrance to a patient's airways, e.g. at a load of approximately 20 to 30 cmH2O pressure.

As an example, an I-beam may comprise a different bending stiffness (resistance to a bending load) in a first direction in comparison to a second, orthogonal direction. In another example, a structure or component may be floppy in a first direction and rigid in a second direction.

5.4.2 Respiratory Cycle

Apnea: According to some definitions, an apnea is said to have occurred when flow falls below a predetermined threshold for a duration, e.g. 10 seconds. An obstructive apnea will be said to have occurred when, despite patient effort, some obstruction of the airway does not allow air to flow. A central apnea will be said to have occurred when an apnea is detected that is due to a reduction in breathing effort, or the absence of breathing effort, despite the airway being patent. A mixed apnea occurs when a reduction or absence of breathing effort coincides with an obstructed airway.

Breathing rate: The rate of spontaneous respiration of a patient, usually measured in breaths per minute.

Duty cycle: The ratio of inhalation time, Ti to total breath time, Ttot.

Effort (breathing): The work done by a spontaneously breathing person attempting to breathe.

Expiratory portion of a breathing cycle: The period from the start of expiratory flow to the start of inspiratory flow.

Flow limitation: Flow limitation will be taken to be the state of affairs in a patient's respiration where an increase in effort by the patient does not give rise to a corresponding increase in flow. Where flow limitation occurs during an inspiratory portion of the breathing cycle it may be described as inspiratory flow limitation. Where flow limitation occurs during an expiratory portion of the breathing cycle it may be described as expiratory flow limitation.

Types of flow limited inspiratory waveforms:(i) Flattened: Having a rise followed by a relatively flat portion, followed by a fall.(ii) M-shaped: Having two local peaks, one at the leading edge, and one at the trailing edge, and a relatively flat portion between the two peaks.(iii) Chair-shaped: Having a single local peak, the peak being at the leading edge, followed by a relatively flat portion.(iv) Reverse-chair shaped: Having a relatively flat portion followed by single local peak, the peak being at the trailing edge.

Hypopnea: According to some definitions, a hypopnea is taken to be a reduction in flow, but not a cessation of flow. In one form, a hypopnea may be said to have occurred when there is a reduction in flow below a threshold rate for a duration. A central hypopnea will be said to have occurred when a hypopnea is detected that is due to a reduction in breathing effort. In one form in adults, either of the following may be regarded as being hypopneas:(i) a 30% reduction in patient breathing for at least 10 seconds plus an associated 4% desaturation; or(ii) a reduction in patient breathing (but less than 50%) for at least 10 seconds, with an associated desaturation of at least 3% or an arousal.

Hyperpnea: An increase in flow to a level higher than normal.

Inspiratory portion of a breathing cycle: The period from the start of inspiratory flow to the start of expiratory flow will be taken to be the inspiratory portion of a breathing cycle.

Patency (airway): The degree of the airway being open, or the extent to which the airway is open. A patent airway is open. Airway patency may be quantified, for example with a value of one (1) being patent, and a value of zero (0), being closed (obstructed).

Positive End-Expiratory Pressure (PEEP): The pressure above atmosphere in the lungs that exists at the end of expiration.

Peak flow rate (Qpeak): The maximum value of flow rate during the inspiratory portion of the respiratory flow waveform.

Respiratory flow rate, patient airflow rate, respiratory airflow rate (Qr): These terms may be understood to refer to the RPT device's estimate of respiratory airflow rate, as opposed to “true respiratory flow rate” or “true respiratory airflow rate”, which is the actual respiratory flow rate experienced by the patient, usually expressed in litres per minute.

Tidal volume (Vt): The volume of air inhaled or exhaled during normal breathing, when extra effort is not applied.

(inhalation) Time (Ti): The duration of the inspiratory portion of the respiratory flow rate waveform.

(exhalation) Time (Te): The duration of the expiratory portion of the respiratory flow rate waveform.

(total) Time (Ttot): The total duration between the start of one inspiratory portion of a respiratory flow rate waveform and the start of the following inspiratory portion of the respiratory flow rate waveform.

Typical recent ventilation: The value of ventilation around which recent values of ventilation Vent over some predetermined timescale tend to cluster, that is, a measure of the central tendency of the recent values of ventilation.

Upper airway obstruction (UAO): includes both partial and total upper airway obstruction. This may be associated with a state of flow limitation, in which the flow rate increases only slightly or may even decrease as the pressure difference across the upper airway increases (Starling resistor behaviour).

Ventilation (Vent): A measure of a rate of gas being exchanged by the patient's respiratory system. Measures of ventilation may include one or both of inspiratory and expiratory flow, per unit time. When expressed as a volume per minute, this quantity is often referred to as “minute ventilation”. Minute ventilation is sometimes given simply as a volume, understood to be the volume per minute.

5.4.3 Ventilation

Adaptive Servo-Ventilator (ASV): A servo-ventilator that has a changeable, rather than fixed target ventilation. The changeable target ventilation may be learned from some characteristic of the patient, for example, a respiratory characteristic of the patient.

Backup rate: A parameter of a ventilator that establishes the minimum breathing rate (typically in number of breaths per minute) that the ventilator will deliver to the patient, if not triggered by spontaneous respiratory effort.

Cycled: The termination of a ventilator's inspiratory phase. When a ventilator delivers a breath to a spontaneously breathing patient, at the end of the inspiratory portion of the breathing cycle, the ventilator is said to be cycled to stop delivering the breath.

Expiratory positive airway pressure (EPAP): a base pressure, to which a pressure varying within the breath is added to produce the desired mask pressure which the ventilator will attempt to achieve at a given time.

End expiratory pressure (EEP): Desired mask pressure which the ventilator will attempt to achieve at the end of the expiratory portion of the breath. If the pressure waveform template Π(Φ) is zero-valued at the end of expiration, i.e. Π(Φ)=0 when Φ=1, the EEP is equal to the EPAP.

Inspiratory positive airway pressure (IPAP): Maximum desired mask pressure which the ventilator will attempt to achieve during the inspiratory portion of the breath.

Pressure support: A number that is indicative of the increase in pressure during ventilator inspiration over that during ventilator expiration, and generally means the difference in pressure between the maximum value during inspiration and the base pressure (e.g., PS=IPAP−EPAP). In some contexts pressure support means the difference which the ventilator aims to achieve, rather than what it actually achieves.

Servo-ventilator: A ventilator that measures patient ventilation, has a target ventilation, and which adjusts the level of pressure support to bring the patient ventilation towards the target ventilation.

Spontaneous/Timed (S/T): A mode of a ventilator or other device that attempts to detect the initiation of a breath of a spontaneously breathing patient. If however, the device is unable to detect a breath within a predetermined period of time, the device will automatically initiate delivery of the breath.

Swing: Equivalent term to pressure support.

Triggered: When a ventilator delivers a breath of air to a spontaneously breathing patient, it is said to be triggered to do so at the initiation of the respiratory portion of the breathing cycle by the patient's efforts.

Typical recent ventilation: The typical recent ventilation Vtyp is the value around which recent measures of ventilation over some predetermined timescale tend to cluster. For example, a measure of the central tendency of the measures of ventilation over recent history may be a suitable value of a typical recent ventilation.

5.4.4 Anatomy

5.4.4.1 Anatomy of the Face

Ala: the external outer wall or “wing” of each nostril (plural: alar)

Alare: The most lateral point on the nasal ala.

Alar curvature (or alar crest) point: The most posterior point in the curved base line of each ala, found in the crease formed by the union of the ala with the cheek.

Auricle: The whole external visible part of the ear.

(nose) Bony framework: The bony framework of the nose comprises the nasal bones, the frontal process of the maxillae and the nasal part of the frontal bone.

(nose) Cartilaginous framework: The cartilaginous framework of the nose comprises the septal, lateral, major and minor cartilages.

Columella: the strip of skin that separates the nares and which runs from the pronasale to the upper lip.

Columella angle: The angle between the line drawn through the midpoint of the nostril aperture and a line drawn perpendicular to the Frankfurt horizontal while intersecting subnasale.

Frankfort horizontal plane: A line extending from the most inferior point of the orbital margin to the left tragion. The tragion is the deepest point in the notch superior to the tragus of the auricle.

Glabella: Located on the soft tissue, the most prominent point in the midsagittal plane of the forehead.

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.

Lip, lower (labrale inferius):

Lip, upper (labrale superius):

Greater alar cartilage: A plate of cartilage lying below the lateral nasal cartilage. It is curved around the anterior part of the naris. Its posterior end is connected to the frontal process of the maxilla by a tough fibrous membrane containing three or four minor cartilages of the ala.

Nares (Nostrils): Approximately ellipsoidal apertures forming the entrance to the nasal cavity. The singular form of nares is naris (nostril). The nares are separated by the nasal septum.

Naso-labial sulcus or Naso-labial fold: The skin fold or groove that runs from each side of the nose to the corners of the mouth, separating the cheeks from the upper lip.

Naso-labial angle: The angle between the columella and the upper lip, while intersecting subnasale.

Otobasion inferior: The lowest point of attachment of the auricle to the skin of the face.

Otobasion superior: The highest point of attachment of the auricle to the skin of the face.

Pronasale: the most protruded point or tip of the nose, which can be identified in lateral view of the rest of the portion of the head.

Philtrum: the midline groove that runs from lower border of the nasal septum to the top of the lip in the upper lip region.

Pogonion: Located on the soft tissue, the most anterior midpoint of the chin.

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

Sagittal plane: A vertical plane that passes from anterior (front) to posterior (rear) dividing the body into right and left halves.

Sellion: Located on the soft tissue, the most concave point overlying the area of the frontonasal suture.

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

Subalare: The point at the lower margin of the alar base, where the alar base joins with the skin of the superior (upper) lip.

Subnasal point: Located on the soft tissue, the point at which the columella merges with the upper lip in the midsagittal plane.

Supramentale: The point of greatest concavity in the midline of the lower lip between labrale inferius and soft tissue pogonion

5.4.4.2 Anatomy of the Skull

Frontal bone: The frontal bone includes a large vertical portion, the squama frontalis, corresponding to the region known as the forehead.

Mandible: The mandible forms the lower jaw. The mental protuberance is the bony protuberance of the jaw that forms the chin.

Maxilla: The maxilla forms the upper jaw and is located above the mandible and below the orbits. The frontal process of the maxilla projects upwards by the side of the nose, and forms part of its lateral boundary.

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.

Nasion: The intersection of the frontal bone and the two nasal bones, a depressed area directly between the eyes and superior to the bridge of the nose.

Occipital bone: The occipital bone is situated at the back and lower part of the cranium. It includes an oval aperture, the foramen magnum, through which the cranial cavity communicates with the vertebral canal. The curved plate behind the foramen magnum is the squama occipitalis.

Orbit: The bony cavity in the skull to contain the eyeball.

Parietal bones: The parietal bones are the bones that, when joined together, form the roof and sides of the cranium.

Temporal bones: The temporal bones are situated on the bases and sides of the skull, and support that part of the face known as the temple.

Zygomatic bones: The face includes two zygomatic bones, located in the upper and lateral parts of the face and forming the prominence of the cheek.

5.4.4.3 Anatomy of the Respiratory System

Diaphragm: A sheet of muscle that extends across the bottom of the rib cage. The diaphragm separates the thoracic cavity, containing the heart, lungs and ribs, from the abdominal cavity. As the diaphragm contracts the volume of the thoracic cavity increases and air is drawn into the lungs.

Larynx: The larynx, or voice box houses the vocal folds and connects the inferior part of the pharynx (hypopharynx) with the trachea.

Lungs: The organs of respiration in humans. The conducting zone of the lungs contains the trachea, the bronchi, the bronchioles, and the terminal bronchioles. The respiratory zone contains the respiratory bronchioles, the alveolar ducts, and the alveoli.

Nasal cavity: The nasal cavity (or nasal fossa) is a large air filled space above and behind the nose in the middle of the face. The nasal cavity is divided in two by a vertical fin called the nasal septum. On the sides of the nasal cavity are three horizontal outgrowths called nasal conchae (singular “concha”) or turbinates. To the front of the nasal cavity is the nose, while the back blends, via the choanae, into the nasopharynx.

Pharynx: The part of the throat situated immediately inferior to (below) the nasal cavity, and superior to the oesophagus and larynx. The pharynx is conventionally divided into three sections: the nasopharynx (epipharynx) (the nasal part of the pharynx), the oropharynx (mesopharynx) (the oral part of the pharynx), and the laryngopharynx (hypopharynx).

5.4.5 Patient Interface

Anti-asphyxia valve (AAV): The component or sub-assembly of a mask system that, by opening to atmosphere in a failsafe manner, reduces the risk of excessive CO2rebreathing by a patient.

Elbow: An elbow is an example of a structure that directs an axis of flow of air travelling therethrough to change direction through an angle. In one form, the angle may be approximately 90 degrees. In another form, the angle may be more, or less than 90 degrees. The elbow may have an approximately circular cross-section. In another form the elbow may have an oval or a rectangular cross-section. In certain forms an elbow may be rotatable with respect to a mating component, e.g. about 360 degrees. In certain forms an elbow may be removable from a mating component, e.g. via a snap connection. In certain forms, an elbow may be assembled to a mating component via a one-time snap during manufacture, but not removable by a patient.

Frame: 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.

Functional Dead Space:

Headgear: Headgear will be taken to mean a form of positioning and stabilizing structure designed for use on a head. For example the headgear may comprise a collection of one or more struts, ties and stiffeners configured to locate and retain a patient interface in position on a patient's face for delivery of respiratory therapy. Some ties are formed of a soft, flexible, elastic material such as a laminated composite of foam and fabric.

Membrane: Membrane will be taken to mean a typically thin element that has, preferably, substantially no resistance to bending, but has resistance to being stretched.

Plenum chamber: a mask plenum chamber will be taken to mean a portion of a patient interface having walls at least partially 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.

Seal: May be a noun form (“a seal”) which refers to a structure, or a verb form (“to seal”) which refers to the effect. Two elements may be constructed and/or arranged to ‘seal’ or to effect ‘sealing’ therebetween without requiring a separate ‘seal’ element per se.

Shell: A shell will be taken to mean a curved, relatively thin structure having bending, tensile and compressive stiffness. For example, a curved structural wall of a mask may be a shell. In some forms, a shell may be faceted. In some forms a shell may be airtight. In some forms a shell may not be airtight.

Stiffener: A stiffener will be taken to mean a structural component designed to increase the bending resistance of another component in at least one direction.

Strut: A strut will be taken to be a structural component designed to increase the compression resistance of another component in at least one direction.

Swivel (noun): A subassembly of components configured to rotate about a common axis, preferably independently, preferably under low torque. In one form, the swivel may be constructed to rotate through an angle of at least 360 degrees. In another form, the swivel may be constructed to rotate through an angle less than 360 degrees. When used in the context of an air delivery conduit, the sub-assembly of components preferably comprises a matched pair of cylindrical conduits. There may be little or no leak flow of air from the swivel in use.

Tie (noun): A structure designed to resist tension.

Vent: (noun): A structure that allows a flow of air from an interior of the mask, or conduit, to ambient air for clinically effective washout of exhaled gases. For example, a clinically effective washout may involve a flow rate of about 10 litres per minute to about 100 litres per minute, depending on the mask design and treatment pressure.

5.4.6 Shape of Structures

Products in accordance with the present technology may comprise one or more three-dimensional mechanical structures, for example a mask cushion or an impeller. The three-dimensional structures may be bounded by two-dimensional surfaces. These surfaces may be distinguished using a label to describe an associated surface orientation, location, function, or some other characteristic. For example a structure may comprise one or more of an anterior surface, a posterior surface, an interior surface and an exterior surface. In another example, a cushion structure may comprise a face-contacting (e.g. outer) surface, and a separate non-face-contacting (e.g. underside or inner) surface. In another example, a structure may comprise a first surface and a second surface.

To facilitate describing the shape of the three-dimensional structures and the surfaces, we first consider a cross-section through a surface of the structure at a point, p. SeeFIG.3BtoFIG.3F, which illustrate examples of cross-sections at point p on a surface, and the resulting plane curves.FIGS.3B to3Falso illustrate an outward normal vector at p. The outward normal vector at p points away from the surface. In some examples we describe the surface from the point of view of an imaginary small person standing upright on the surface.

5.4.6.1 Curvature in One Dimension

The curvature of a plane curve at p may be described as having a sign (e.g. positive, negative) and a magnitude (e.g. 1/radius of a circle that just touches the curve at p).

Positive curvature: If the curve at p turns towards the outward normal, the curvature at that point will be taken to be positive (if the imaginary small person leaves the point p they must walk uphill). SeeFIG.3B(relatively large positive curvature compared toFIG.3C) andFIG.3C(relatively small positive curvature compared toFIG.3B). Such curves are often referred to as concave.

Zero curvature: If the curve at p is a straight line, the curvature will be taken to be zero (if the imaginary small person leaves the point p, they can walk on a level, neither up nor down). SeeFIG.3D.

Negative curvature: If the curve at p turns away from the outward normal, the curvature in that direction at that point will be taken to be negative (if the imaginary small person leaves the point p they must walk downhill) SeeFIG.3E(relatively small negative curvature compared toFIG.3F) andFIG.3F(relatively large negative curvature compared toFIG.3E). Such curves are often referred to as convex.

5.4.6.2 Curvature of Two Dimensional Surfaces

A description of the shape at a given point on a two-dimensional surface in accordance with the present technology may include multiple normal cross-sections. The multiple cross-sections may cut the surface in a plane that includes the outward normal (a “normal plane”), and each cross-section may be taken in a different direction. Each cross-section results in a plane curve with a corresponding curvature. The different curvatures at that point may have the same sign, or a different sign. Each of the curvatures at that point has a magnitude, e.g. relatively small. The plane curves inFIGS.3B to3Fcould be examples of such multiple cross-sections at a particular point.

Principal curvatures and directions: The directions of the normal planes where the curvature of the curve takes its maximum and minimum values are called the principal directions. In the examples ofFIG.3BtoFIG.3F, the maximum curvature occurs inFIG.3B, and the minimum occurs inFIG.3F, henceFIG.3BandFIG.3Fare cross sections in the principal directions. The principal curvatures at p are the curvatures in the principal directions.

Region of a surface: A connected set of points on a surface. The set of points in a region may have similar characteristics, e.g. curvatures or signs.

Saddle region: A region where at each point, the principal curvatures have opposite signs, that is, one is positive, and the other is negative (depending on the direction to which the imaginary person turns, they may walk uphill or downhill)

Dome region: A region where at each point the principal curvatures have the same sign, e.g. both positive (a “concave dome”) or both negative (a “convex dome”).

Cylindrical region: A region where one principal curvature is zero (or, for example, zero within manufacturing tolerances) and the other principal curvature is non-zero.

Planar region: A region of a surface where both of the principal curvatures are zero (or, for example, zero within manufacturing tolerances).

Edge of a surface: A boundary or limit of a surface or region.

Path: In certain forms of the present technology, ‘path’ will be taken to mean a path in the mathematical—topological sense, e.g. a continuous space curve from f(0) to f(1) on a surface. In certain forms of the present technology, a ‘path’ may be described as a route or course, including e.g. a set of points on a surface. (The path for the imaginary person is where they walk on the surface, and is analogous to a garden path).

Path length: In certain forms of the present technology, ‘path length’ will be taken to the distance along the surface from f(0) to f(1), that is, the distance along the path on the surface. There may be more than one path between two points on a surface and such paths may have different path lengths. (The path length for the imaginary person would be the distance they have to walk on the surface along the path).

Straight-line distance: The straight-line distance is the distance between two points on a surface, but without regard to the surface. On planar regions, there would be a path on the surface having the same path length as the straight-line distance between two points on the surface. On non-planar surfaces, there may be no paths having the same path length as the straight-line distance between two points. (For the imaginary person, the straight-line distance would correspond to the distance ‘as the crow flies’.)

5.4.6.3 Space Curves

Space curves: Unlike a plane curve, a space curve does not necessarily lie in any particular plane. A space curve may be considered to be a one-dimensional piece of three-dimensional space. An imaginary person walking on a strand of the DNA helix walks along a space curve. A typical human left ear comprises a left-hand helix, seeFIG.3P. A typical human right ear comprises a right-hand helix, seeFIG.3Q.FIG.3Rshows a right-hand helix. The edge of a structure, e.g. the edge of a membrane or impeller, may follow a space curve. In general, a space curve may be described by a curvature and a torsion at each point on the space curve. Torsion is a measure of how the curve turns out of a plane. Torsion has a sign and a magnitude. The torsion at a point on a space curve may be characterised with reference to the tangent, normal and binormal vectors at that point.

Tangent unit vector (or unit tangent vector): For each point on a curve, a vector at the point specifies a direction from that point, as well as a magnitude. A tangent unit vector is a unit vector pointing in the same direction as the curve at that point. If an imaginary person were flying along the curve and fell off her vehicle at a particular point, the direction of the tangent vector is the direction she would be travelling.

Unit normal vector: As the imaginary person moves along the curve, this tangent vector itself changes. The unit vector pointing in the same direction that the tangent vector is changing is called the unit principal normal vector. It is perpendicular to the tangent vector.

Binormal unit vector: The binormal unit vector is perpendicular to both the tangent vector and the principal normal vector. Its direction may be determined by a right-hand rule (see e.g.FIG.3O), or alternatively by a left-hand rule (FIG.3N).

Osculating plane: The plane containing the unit tangent vector and the unit principal normal vector. SeeFIGS.3N and3O.

Torsion of a space curve: The torsion at a point of a space curve is the magnitude of the rate of change of the binormal unit vector at that point. It measures how much the curve deviates from the osculating plane. A space curve which lies in a plane has zero torsion. A space curve which deviates a relatively small amount from the osculating plane will have a relatively small magnitude of torsion (e.g. a gently sloping helical path). A space curve which deviates a relatively large amount from the osculating plane will have a relatively large magnitude of torsion (e.g. a steeply sloping helical path). With reference toFIG.3R, since T2>T1, the magnitude of the torsion near the top coils of the helix ofFIG.3Ris greater than the magnitude of the torsion of the bottom coils of the helix ofFIG.3R

With reference to the right-hand rule ofFIG.3O, a space curve turning towards the direction of the right-hand binormal may be considered as having a right-hand positive torsion (e.g. a right-hand helix as shown inFIG.3R). A space curve turning away from the direction of the right-hand binormal may be considered as having a right-hand negative torsion (e.g. a left-hand helix).

Equivalently, and with reference to a left-hand rule (seeFIG.3N), a space curve turning towards the direction of the left-hand binormal may be considered as having a left-hand positive torsion (e.g. a left-hand helix). Hence left-hand positive is equivalent to right-hand negative. SeeFIG.3S.

5.4.6.4 Holes

A surface may have a one-dimensional hole, e.g. a hole bounded by a plane curve or by a space curve. Thin structures (e.g. a membrane) with a hole, may be described as having a one-dimensional hole. See for example the one dimensional hole in the surface of structure shown inFIG.3I, bounded by the plane curve301D.

A structure may have a two-dimensional hole, e.g. a hole bounded by a surface. For example, an inflatable tyre has a two dimensional hole bounded by the inside surface of the tyre. In another example, a bladder with a cavity for air or gel could have a two-dimensional hole. See for example the cushion ofFIG.3Land the example cross-section there through inFIG.3M. In a yet another example, a conduit may comprise a one-dimension hole (e.g. at its entrance or at its exit), and a two-dimension hole bounded by the inside surface of the conduit. See also the two dimensional hole through the structure shown inFIG.3K, bounded by surface302D.

5.5 Other Remarks

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 Patent Office patent files or records, but otherwise reserves all copyright rights whatsoever.

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.

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.

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.

When a particular material is identified as being 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.

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.

All publications mentioned herein are incorporated herein by reference in their entirety 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.

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.

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.

Although the technology herein has been described with reference to particular examples, it is to be understood that these examples 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.

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

For example, it should be appreciated that one or more features of any one patient interface example (e.g., patient interfaces6000,7000,16000) may be combinable with one or more features of another patient interface example (e.g., patient interfaces6000,7000,16000) or other examples related thereto. For example, one or more aspects of the frame assembly16100(e.g., lockout feature, headgear connector arms, connection and sealing arrangement between components) may be incorporated into the patient interfaces6000,7000.

Also, it should be appreciated that one or more aspects of the present technology may be combinable with one or more aspects of: PCT Application No. PCT/AU2016/050892, filed Sep. 23, 2016 and entitled “Elbow Assembly”, which claims the benefit of U.S. Provisional Application No. 62/222,435, filed Sep. 23, 2015 and U.S. Provisional Application No. 62/376,718, filed Aug. 18, 2016; U.S. Provisional Application No. 62/377,217, filed Aug. 19, 2016 and entitled “Patient Interface with a Seal-Forming Structure having Varying Thickness”; U.S. Provisional Application No. 62/377,158, filed Aug. 19, 2016 and entitled “Patient Interface with a Seal-Forming Structure having Varying Thickness”; PCT Application No. PCT/AU2016/050893, filed Sep. 23, 2016 and entitled “Vent Adaptor for a Respiratory Therapy System”, which claims the benefit of U.S. Provisional Application No. 62/222,604, filed Sep. 23, 2015; and/or PCT Application No. PCT/AU2016/050228 filed Mar. 24, 2016 and entitled “Patient Interface with Blowout Prevention for Seal-Forming Portion”, which claims the benefit of U.S. Provisional Application No. 62/138,009, filed Mar. 25, 2015 and U.S. Provisional Application No. 62/222,503, filed Sep. 23, 2015; each of the above-noted applications of which is incorporated herein by reference in its entirety.

5.6 Reference Signs List

NumberFeature Item1000patient1100bed partner3000patient interface3100seal—forming structure3200plenum chamber3300positioning and stabilising structure3400vent3600connection port3700forehead support4000RPT device4170air circuit5000humidifier6000patient interface6100frame assembly6105opening6110shroud6111groove6112groove6113openings6114openings6115flange6117rim6120channel6125spring arm6127protrusion6130upper headgear connector6132shroud connection portion6133pins6134upper headgear connector arm6135upper headgear connection point6140central flexible portion6141slot6143first rigid portion6145peripheral flexible portion6146slot6147second rigid portion6150lower headgear connector6152shroud connection portion6153pins6154lower headgear connector arm6155magnetic connector6156receptacle6160headgear clip6162magnet6175cushion assembly6180shell6200seal—forming structure6250lip seal6305opening6310flange6315catch6320recess6500plenum chamber6600elbow assembly6610first end portion6620second end portion6625swivel connector6630side wall6650pinch arm6652tab6700vent6750arm cover6800headgear6802upper side strap6804lower side strap6806crown strap7000patient interface7100frame assembly7105opening7110shroud7125spring arm7127protrusion7130headgear connector7132shroud connection portion7133intermediate portion7134upper headgear connector arm7135slot7140flexible portion7149connecting portion7154lower headgear connector arm7155magnetic connector7160headgear clip7175cushion assembly7180shell7200seal—forming structure7250seal7310flange7315catch7320recess7500plenum chamber7600elbow assembly7630side wall7700vent assembly7800headgear7802upper headgear strap7804lower headgear strap8100frame assembly8175cushion assembly8250bellows structure8275surface8600elbow assembly8900vent adaptor connector9600elbow assembly16000patient interface16100frame assembly16105opening16110shroud16112Aend wall16112Bside wall16115outer annular flange16117rim16120channel16125inner annular flange16127tab or catch16132shroud connection portion16133protrusion16133Aopening16134upper headgear connector arm16135upper headgear connection point16136bridge16136Aleading edge16137cap16138protrusion16140central flexible portion16141slot16145peripheral flexible portion16146slot16152shroud connection portion16153protrusion16153Aopening16154lower headgear connector arm16155magnetic connector16155Amagnet receiving portion16155Bmagnet16155Ccover16156slot16157cap16158protrusion16159slot16160headgear clip16162magnet16164catch16175cushion assembly16180shell16200seal—forming structure16305opening16310flange16310Aleading edge16310Bouter side16400ridge16405projections16407opening16450upper anchor16452opening16454bridge member16456ribs16460lower anchor16462opening16500plenum chamber16600elbow assembly16610first end portion16620second end portion16625swivel connector16630inner wall16640outer wall16645channel16650pinch arm16652barbed end16700vent holes16750arm cover16800headgear16802upper side strap16803tab16804lower side strap16806crown strap17110shroud17134connector arm17154lower arm17157cap17450anchor