Patent Description:
The prior art includes a wide variety of interfaces for supplying gases to a recipient. The following are examples.

The prior art includes a nasal mask that can be used for supplying gases to a recipient. The nasal mask includes a perimeter seal that seals across, down each cheek alongside the nose and along the surface of the upper lip. The entire enclosed space is pressurised and the recipient may inhale the pressurised gas from the enclosed space. An example is the Flexifit <NUM> nasal mask sold by Fisher & Paykel Healthcare.

The prior art also includes a full face mask. The full face mask includes a perimeter seal that extends across the bridge of the nose downward along each cheek beside the nose to the jaw and along the jaw below the lower lip. The perimeter thereby encloses both the nose and mouth. The entire space within the mask frame is pressurised. The recipient may breathe the pressurised gas from the space through either the nose or mouth. An example is the Flexifit <NUM> interface sold by Fisher & Paykel Healthcare.

The prior art further includes an oral interface including an oral appliance that fits within the user's mouth. An example is the Fisher & Paykel Healthcare Oracle interface.

The prior art still further includes a nasal pillows interface in which headgear retains a soft plenum in the vicinity of the user's nose. A pair of flexible protrusions engage against the nares of the recipient. Typically, the protrusions are able to axially compress and have a lateral freedom of movement relative to the supporting cushion. Examples are the ResMed Mirage Swift™ II, the ResMed Swift LT, or the Fisher and Paykel Opus™ <NUM>. A variety of different pillow configurations which could be used with these interfaces are described and shown in <CIT>.

The prior art still further includes a nasal cannula interface. The nasal cannula interface includes a plenum portion that rests against the upper lip of the user and a pair of prongs. Each prong extends into the nostril of the user. An example is the Nasal-Aire interface made by Innomed, where gases are provided to the interface and the prongs by conduits or hoses that extend from the users nose across their cheeks, over their ears and around the back of their head.

<CIT> discloses a nasal assembly for delivering breathable gas to a patient that includes a frame having an integrally formed first connector portion. A nozzle assembly includes a gusset or base portion and a pair of nozzles. At least one inlet conduit is structured to deliver breathable gas into the frame and nozzle assembly for breathing by the patient. A pair of second connector portions are removably and rotatably connected to respective first connector portions of the frame and are in communication with respective inlet conduits, e.g., directly or via angle connectors. A headgear assembly is removably connected to the pair of second connector portions and/or the angle connectors so as to maintain the frame and the nozzle assembly in a desired adjusted position on the patient's face.

<CIT> discloses a nasal cannula, shaped to fit within a user's nares, where the nasal cannula includes at least one prong allowing high flow delivery of humidified gases and creates positive airway pressure in the patient's airway. The prongs have angled ends, such that in use, gases flowing through the prongs are directed to the user's nasal passages. The nasal cannula body is partially swivelling and preferably has a ball joint connector.

Interfaces such as these are frequently used for delivering pressurised gases to a person being treated for obstructive sleep apnea (OSA) or other sleep disorders. These users typically wear the interface in a home sleeping environment. Comfort and effective sealing even under conditions of patient movement are major considerations.

The term "comprising" as used in this specification means "consisting at least in part of". When interpreting each statement in this specification that includes the term "comprising", features other than that or those prefaced by the term may also be present. Related terms such as "comprise" and "comprises" are to be interpreted in the same manner.

It is an object of the present invention to provide an interface that goes some way towards overcoming the disadvantages of the prior art such as the devices described above, or which at least provides users with a useful choice.

Preferred embodiments are matter of the dependent claims. Subject-matter referred as embodiments, aspects and/or disclosures which do not fall under the scope of the claims are not part of the invention.

In a first aspect, which corresponds to the present invention, there is provided a nasal pillow section for use as part of an apparatus for providing a stream of gases to a user, said pillow section in use located in front of the upper lip and below the nostrils of a user, said pillow section comprising, when viewed from the front and to one side of the nasal pillow section being worn by the user who is standing up:.

Preferably said lower inner surface in said first aspect is shaped as a concavity.

Preferably said pillow gasket in said first aspect includes an open lower front portion that acts as said gases aperture, and said concavity runs generally between the base or bases of said nasal pillows, and the lower rear part of said open lower front portion.

Preferably the inwards curve of the concavity for said lower inner surface in said first aspect is <NUM> from the lower edge to the upper edge.

Preferably said lower inner surface in said first aspect preferably has a width of between <NUM> and <NUM> and most preferably <NUM>.

Preferably the height of said lower inner surface between the outer side of said pillows and the lower rear part of said open lower front portion wall in said first aspect is preferably between <NUM> and <NUM> and most preferably between <NUM> and <NUM>.

Preferably the height of said lower inner surface between the inner side of said pillows, and the lower rear part of said open lower front portion wall in said first aspect is preferably between <NUM> and <NUM> and less than the height of said lower inner surface between the outer side of said pillows and the lower rear part of said open lower front portion wall and most preferably between <NUM> and <NUM>.

Alternatively said lower inner surface in said first aspect is a substantially straight forward-sloping planar surface.

Preferably said pillow gasket in said first aspect includes an open lower front portion that acts as said gases aperture, and said substantially straight forward-sloping planar surface runs generally between the base or bases of said nasal pillows, and the lower rear part of said open lower front portion.

Alternatively said lower inner surface in said first aspect is slightly convex.

Preferably said pillow gasket includes an open lower front portion that acts as said gases aperture, and said slightly convex lower inner surface runs generally between the base or bases of said nasal pillows, and the lower rear part of said open lower front portion, said surface deviating <NUM> or less from a straight line running between the base or bases of said nasal pillows, and the lower rear part of said open lower front portion.

In a second aspect the disclosure may broadly be said to consist in a nasal pillow section for use as part of an apparatus for providing a stream of gases to a user, said pillow section in use located in front of the upper lip and below the nostrils of a user, said pillow section comprising:.

Preferably said nasal pillow section in said second aspect includes an open lower front portion that acts as said gases aperture, and said concavity runs generally between the base or bases of said nasal pillows, and the lower rear part of said open lower front portion.

Preferably the inwards curve of the concavity for said lower inner surface in said second aspect is <NUM> from the lower edge to the upper edge.

Preferably said lower inner surface in said second aspect preferably has a width of between <NUM> and <NUM> and most preferably <NUM>.

Preferably the height of said lower inner surface between the outer side of said pillows and the lower rear part of said open lower front portion wall in said second aspect is preferably between <NUM> and <NUM> and most preferably between <NUM> and <NUM>.

Preferably the height of said lower inner surface between the inner side of said pillows, and the lower rear part of said open lower front portion wall in said second aspect is preferably between <NUM> and <NUM> and less than the height of said lower inner surface between the outer side of said pillows and the lower rear part of said open lower front portion wall and most preferably between <NUM> and <NUM>.

In a third aspect the diclosure may broadly be said to consist in a nasal pillow section for use as part of an apparatus for providing a stream of gases to a user, said pillow section in use located in front of the upper lip and below the nostrils of a user, comprising:.

In a fourth aspect the disclosure may broadly be said to consist in a nasal pillow section for use as part of an apparatus for providing a stream of gases to a user, said pillow section in use located in front of the upper lip and below the nostrils of a user, said pillow section comprising:.

Preferably said pillow gasket in said fourth aspect includes an open lower front portion that acts as said gases aperture, and said slightly convex lower inner surface runs generally between the base or bases of said nasal pillows, and the lower rear part of said open lower front portion, said surface deviating <NUM> or less from a straight line running between the base or bases of said nasal pillows, and the lower rear part of said open lower front portion.

In a fifth aspect the disclosure may broadly be said to consist in an interface for use as part of an apparatus for providing a stream of gases to a user, comprising:.

Preferably said lower inner surface in said fifth aspect is shaped as a concavity.

Preferably said pillow gasket in said fifth aspect includes an open lower front portion that acts as a gases aperture and which is fluidically connected to said manifold section, and said concavity runs generally between the base or bases of said nasal pillows, and the lower rear part of said open lower front portion.

Preferably the inwards curve of the concavity for said lower inner surface in said fifth aspect is <NUM> from the lower edge to the upper edge.

Preferably said lower inner surface in said fifth aspect preferably has a width of between <NUM> and <NUM> and most preferably <NUM>.

Preferably the height of said lower inner surface between the outer side of said pillows and the lower rear part of said open lower front portion wall in said fifth aspect is preferably between <NUM> and <NUM> and most preferably between <NUM> and <NUM>.

Preferably the height of said lower inner surface between the inner side of said pillows, and the lower rear part of said open lower front portion wall in said fifth aspect is preferably between <NUM> and <NUM> and less than the height of said lower inner surface between the outer side of said pillows and the lower rear part of said open lower front portion wall and most preferably between <NUM> and <NUM>.

Alternatively said lower inner surface in said fifth aspect is a substantially straight forward-sloping planar surface.

Preferably said pillow gasket in said fifth aspect includes an open lower front portion that acts as a gases aperture and which is fluidically connected to said manifold section, and said substantially straight forward-sloping planar surface runs generally between the base or bases of said nasal pillows, and the lower rear part of said open lower front portion.

Alternatively said lower inner surface in said fifth aspect is slightly convex.

Preferably said pillow gasket in said fifth aspect includes an open lower front portion that acts as a gases aperture and which is fluidically connected to said manifold section, and said slightly convex lower inner surface runs generally between the base or bases of said nasal pillows, and the lower rear part of said open lower front portion, said convex surface deviating <NUM> or less from a straight line running between the base or bases of said nasal pillows, and the lower rear part of said open lower front portion.

In a sixth aspect the disclosure may broadly be said to consist in an interface for use as part of an apparatus for providing a stream of gases to a user, comprising:.

Preferably said pillow gasket in said sixth aspect includes an open lower front portion that acts as a gases aperture and which is fluidically connected to said manifold section, and said concavity runs generally between the base or bases of said nasal pillows, and the lower rear part of said open lower front portion.

Preferably said lower inner surface in said sixth aspect preferably has a width of between <NUM> and <NUM> and most preferably <NUM>.

Preferably the height of said lower inner surface between the outer side of said pillows and the lower rear part of said open lower front portion wall in said sixth aspect is preferably between <NUM> and <NUM> and most preferably between <NUM> and <NUM>.

Preferably the height of said lower inner surface between the inner side of said pillows, and the lower rear part of said open lower front portion wall in said sixth aspect is preferably between <NUM> and <NUM> and less than the height of said lower inner surface between the outer side of said pillows and the lower rear part of said open lower front portion wall and most preferably between <NUM> and <NUM>.

In a seventh aspect the disclosure may broadly be said to consist in an interface for use as part of an apparatus for providing a stream of gases to a user, comprising:.

In an eighth aspect the disclosure may broadly be said to consist in an interface for use as part of an apparatus for providing a stream of gases to a user, comprising:.

Preferably said pillow gasket in said eighth aspect includes an open lower front portion that acts as a gases aperture and which is fluidically connected to said manifold section, and said slightly convex lower inner surface runs generally between the base or bases of said nasal pillows, and the lower rear part of said open lower front portion, said surface deviating <NUM> or less from a straight line running between the base or bases of said nasal pillows, and the lower rear part of said open lower front portion.

In a ninth aspect the disclosure may broadly be said to consist in a system for providing a heated, humidified stream of gases to a user, comprising:.

To those skilled in the art to which the invention relates, many changes in construction and widely differing embodiments and applications of the invention will suggest themselves without departing from the scope of the invention as defined in the appended claims. The disclosures and the descriptions herein are purely illustrative and are not intended to be in any sense limiting.

The present technology will now be described with reference to the accompanying drawings in which:.

The present invention provides an interface for use as part of an apparatus for providing a stream of gases to a patient. The preferred and alternative embodiments are for use as part of an apparatus for providing a stream of heated, humidified gases at a pressure above atmospheric pressure to a user for the purposes of CPAP therapy or similar. However, it should be noted that the interface is not limited for use as part of an apparatus for providing CPAP therapy - the interface could also be used for Bi-PAP or variable pressure therapy, as part of an apparatus used for an anti-snoring treatment regime, for the treatment of COPD, or as part of any therapy regime where a stream of gases at a pressure greater than atmospheric is delivered to the breathing passages of a patient or user via an interface assembly.

The preferred embodiment will now be described in detail with reference to the Figures. However, it should be noted that many variations are possible which have not been specifically described, without departing from the intended scope of the present invention.

<FIG> shows a schematic view of a typical system <NUM> for providing a stream of heated humidified gases at a pressure above atmospheric to a user <NUM>. The system <NUM> includes a gases supply unit or blower unit <NUM> which in use receives gases from atmosphere and passes these through a fan unit <NUM> or similar inside the blower unit so that when the gases leave the blower unit <NUM>, they are at a pressure above atmospheric, and are flowing at a certain flow rate. A humidifier unit <NUM> is located downstream from the blower unit <NUM>, and in use receives the flow of pressurised gases from the blower unit <NUM>. The humidifier unit <NUM> includes a water chamber <NUM> which in use contains a volume of water <NUM>. The volume of water <NUM> in the chamber <NUM> is in use heated - in the embodiment shown in <FIG>, the water <NUM> is heated by a heater plate <NUM> located underneath the chamber <NUM>. The gases from the blower unit <NUM> pass into the chamber <NUM> via an entry port <NUM>, the gases passing through the chamber <NUM> and across the surface of the water <NUM>, becoming heated and humidified as they do so. The gases then pass out of the humidifier chamber <NUM> via a humidifier outlet port <NUM>. It should be noted that there are many different ways in which the gases could be heated and humidified aside from the specific way described above, and any of these different ways are suitable for use as part of the system that uses the pillows of the present invention.

It should also be noted that a modular system has been described above - that is, a system where the humidifier unit <NUM> is a separate unit to the blower unit <NUM>. An integrated system could also be used - that is, a system where the blower unit and the humidifier unit are two integral parts of a single unit, or where the blower unit and the humidifier unit are rigidly attached or connected together in use.

In use, one end of a main supply conduit <NUM> is connected to the humidifier outlet <NUM>. The heated and humidified gases stream exits the humidifier unit <NUM> via the humidifier outlet <NUM> and enters the main supply conduit <NUM>, passing along the supply conduit <NUM> to an interface assembly <NUM> which is connected to the user end of the supply conduit <NUM>. The supply conduit <NUM> can either be directly connected to the interface assembly <NUM>, as shown in <FIG>, or an intervening interface conduit <NUM> can be used to connect between the main supply conduit <NUM> and the interface assembly <NUM>, as shown in the embodiments of <FIG>, <FIG> and <FIG>. Where the supply conduit <NUM> is referred to below, this should be taken to mean either the supply conduit <NUM> by itself, or alternatively as referring to the supply conduit in combination with the interface conduit <NUM>.

In the preferred embodiment, the supply conduit <NUM> is a flexible tube formed from a plastic type material, many different variations of which are known in the art. One end of the supply conduit <NUM> is connected to the humidifier outlet port <NUM>, with the other end connected either directly to the interface assembly <NUM>, or connected to the distal end 190a of the interface conduit <NUM>, the interface conduit <NUM> connected to the interface core section <NUM>. The most preferred form of interface conduit <NUM> is approximately <NUM> or <NUM> foot in length, with an external diameter of between <NUM>-<NUM> and a thin ribbed wall, the ribs being approximately <NUM>-<NUM> thick and the wall between the ribs being significantly less that <NUM> thick. However, it should be noted that variations from these dimensions are possible without departing from the scope of the invention, and for example a non-ribbed conduit could be used if required. It should further be noted that `flexible tube' as it is used in this specification should be taken to mean that the tube or conduit is flexible enough so that it is capable of being bent or deformed repeatedly (for example, by bringing the two ends of the conduit together, or by tying a loose knot in the conduit if it is long enough - e.g. approximately <NUM> or more in length), with the tube or conduit returning to its original undeformed shape with little to no plastic deformation occurring, every single time the tube or conduit is bent or deformed in this manner.

In the most preferred form, neither of the supply conduit <NUM> or the interface conduit <NUM> will rigidly support their own weight when held at one end so that the main body of the conduit extends outwards generally horizontally from the held end. Over a <NUM>-<NUM> length of supply conduit (which has a diameter of <NUM>-<NUM> and a wall thickness at the ribs of <NUM>-<NUM> and a wall thickness between the ribs of less than <NUM>), the unsupported end of the interface conduit will bend to face substantially directly downwards. For example, the interface conduit of the Swift LT™ is formed in such a manner that over a <NUM>-<NUM> length, the unsupported end will bend downwards so that it points substantially vertically downwards. The interface conduit used in the Opus is somewhat stiffer, but will still bend through an angle of very approximately <NUM> degrees. Both of these conduits are flexible for the purposes of this specification, and should not be thought of as 'rigid' or 'semi-rigid' (see Lexicon section for more details). The main supply conduit <NUM> is of similar flexibility to both of these items, but is generally slightly less flexible.

The conduits <NUM>, <NUM> connect to each other, or to the interface assembly <NUM>, or both, by a friction push fit, a bayonet connection or similar, or by any other suitable connection as might be known in the art.

Specific preferred forms of an interface assembly are shown in <FIG>, <FIG>, and <FIG> as interface assembly <NUM>, interface assembly <NUM> or interface assembly <NUM>. The interface assemblies <NUM>, <NUM>, <NUM> have a number of common elements and differences as will be described below. In the description below, the element numbering conforms to the following convention: For the embodiment of <FIG>, the elements unique to that embodiment will be numbered e.g. <NUM>, <NUM>, etc. The equivalent unique elements on the embodiments shown in <FIG> and <FIG> will be numbered e.g. <NUM>, <NUM> and <NUM>, <NUM> respectively. If the element is being referred to in a general sense, it will be referred to as e.g. <NUM>, <NUM> etc to show that the description is applicable to all the embodiments shown in <FIG>, <FIG>, <FIG>, and could also be applied as a general description to other, general, embodiments not specifically shown.

The interface assembly (e.g. assemblies <NUM>, <NUM>, <NUM>) are assembled from two main parts: an interface core portion or interface core section <NUM>, and a headgear assembly <NUM>.

The interface core section <NUM> and the supply conduit <NUM> (either including or excluding the interface conduit <NUM>) are mutually adapted so that one end (the patient end or proximal end) of the supply conduit <NUM> is fluidically or gaseously connected to the interface core section <NUM> in use, the interface core section <NUM> adapted so that the supply of heated, humidified gases is provided to the interior of the interface core portion <NUM> from the supply conduit <NUM> via this connection. The preferred forms of this connection will be described in detail below.

The headgear assembly <NUM> is formed from two main items: a set of arms <NUM> that extend in use one from each side of the interface core portion <NUM>, and a set of headgear straps <NUM>. In the preferred embodiments, the arms <NUM> are formed from either a flexible or a semi-rigid plastic, backed with neoprene, foam, or similar to form a cushion portion, the cushion portion resting against the face of a user in use.

The arms <NUM> can be connected to the interface core portion <NUM> in a number of ways. For example, arms <NUM> could be integrally formed or integrally connected with the interface core portion <NUM>, as shown in the embodiment of <FIG> - the arms <NUM> are formed as part of the interface core portion <NUM>. Alternatively, the arms, such as arms <NUM>, could be removably or releasably connected to the interface core portion <NUM> as shown in the embodiment of <FIG>. In the specific embodiment of <FIG>, the releasable connection is made in such a manner as to allow the arms <NUM> to be rotatably adjusted with respect to the interface core portion <NUM>. The embodiment of <FIG> with the adjustable arms shows an interface assembly <NUM> that has an interface core portion <NUM> and arms <NUM>. The interface ends of the arms <NUM> are rotatably connected to the interface core portion <NUM> by way of a `rotating barrel' connection as is used on the ResMed Swift™ LT, which allows the arms <NUM> to rotate relative to the interface core portion <NUM>, and still remain connected. The mutual connection is formed so that when the connection is made, the arm <NUM> will remain in the position to which a user has rotated it - the arm <NUM> will not freely rotate unless manipulated by an external force.

For all of the preferred forms, the headgear straps <NUM> extend around the rear, or over the top of a user's head (or both) in use, to support the interface assembly <NUM> in position in use. In the embodiment of <FIG>, the ends of the arms <NUM> in use co-locate with the ends of the headgear straps <NUM>, with the ends of the arms <NUM> and the ends of the headgear straps <NUM> mutually adapted to connect together in use to hold the interface assembly <NUM> in position. In this form, the ends of the main strap <NUM> include two patches of Velcro™ on the outer surface at each end - one 'hook' patch and one 'loop' patch. When each of the ends is doubled back on itself to form a loop, the Velcro™ patches engage to hold this loop together. In use, the ends <NUM>, <NUM> are passed one each through slots <NUM> on the ends of the arms <NUM> and then doubled back on themselves to engage the headgear assembly <NUM> with the core section <NUM>. This arrangement could be used on other embodiments if required.

In alternative embodiments, such as those shown in <FIG> and <FIG>, the headgear straps <NUM>, <NUM> could be formed as an extension of the cushion portion, with the headgear straps <NUM>, <NUM> formed from neoprene or similar. For example, in the embodiment shown in <FIG>, the headgear straps <NUM> are a single-piece item with the arms <NUM>.

It is preferred that all the different embodiments of headgear straps <NUM> include a secondary upper strap <NUM> which passes across the top of a user's head, as well as the main strap <NUM> which passes behind the user's head. The secondary upper strap <NUM> is arranged so that it passes across the top of a users head, with each end of the secondary strap <NUM> connecting to the main strap <NUM> just behind the ears of a user. Each of these straps <NUM>, <NUM> includes an adjustment mechanism such as buckles 15a, 15b or similar. These could be Velcro™ adjusters or buckles as preferred. The headgear secondary upper strap <NUM> could also be independently formed and connected to the main strap <NUM>. The adjustments could be at any location on the strap that is convenient - sides, front or rear. The straps <NUM>, <NUM> could be of different widths or thicknesses as required for user comfort. For example, in the most preferred form, the main strap <NUM> is wider than the secondary strap <NUM>.

Suitable strap materials may include a woven elastic strip or a narrow strip of foam and fabric, such as Breathoprene™. Alternatively, the headgear could be formed from silicone, or coated with silicone. The headgear arms could be padded or cushioned on their inside surfaces if they are formed from silicone, in order to increase user comfort. Padding could also be added to the preferred form of arms - those made from Breathoprene™ or similar.

The interface core section <NUM> of the preferred forms is formed so as to act as a manifold in use, receiving gases from the supply conduit <NUM>. The connection between the interface core section <NUM> and the patient or user end of the supply conduit <NUM> can be made by way of a push-fit connection or similar. In one preferred form (not specifically shown), the interface core section <NUM> is formed as a one-piece item, and an aperture or connector portion which is adapted to receive the patient end of the supply conduit <NUM> is formed directly in this one-piece item. In this form, the end of the supply conduit <NUM> is connected directly to the one-piece interface core section <NUM> - e.g. by pushing it into the aperture located on the interface core section <NUM>, or by connecting it to the connector portion. However, in other preferred forms, this aperture is located on a separate sub-item or sub-assembly that is included as part of the interface core portion <NUM> when the interface core section <NUM> is assembled, but is initially formed as a separate item.

An example of an interface core section <NUM> that has a manifold section and a connector that is initially formed as a separate item is shown in <FIG>. The interface core section <NUM> includes a manifold section <NUM>-<NUM> and an elbow connector <NUM>-<NUM>. One end of the elbow connector <NUM>-<NUM> is formed as a ball joint <NUM>, and this locates into a socket <NUM> on the front of the manifold section <NUM>-<NUM> in use, the socket <NUM> adapted to act as a gases supply aperture. This allows a degree of three-dimensional relative movement, or movement in more than one plane, between the manifold section <NUM>-<NUM> and the elbow connector <NUM>-<NUM>. That is, as well as being able to rotate through <NUM> degrees in a plane running across the front of a user's face, the elbow connector <NUM>-<NUM> also has a limited degree of up/down rotation and side/side rotation relative to the manifold section <NUM>-<NUM>.

An example of a second preferred form of interface core section <NUM> that includes an elbow connector is shown in <FIG>. A manifold portion or manifold section <NUM>-<NUM> is shown, the manifold section <NUM>-<NUM> including an aperture located at the front of the manifold section <NUM>-<NUM>. An elbow connector <NUM>-<NUM> is connected to the manifold section <NUM>-<NUM> via the aperture, with one end of the elbow connector <NUM>-<NUM> locating into or connected to the aperture, and the other connected to the supply conduit <NUM>. The manifold section <NUM>-<NUM> and the elbow connector <NUM>-<NUM> are mutually adapted to provide a <NUM> degree swivel - the elbow connector <NUM>-<NUM> and the manifold section <NUM>-<NUM> can swivel or rotate through <NUM> degrees relative to one another in use, in a plane across the front of a user's face, as shown in <FIG>. The manifold section <NUM>-<NUM> and the elbow connector <NUM>-<NUM> are assembled together to form part of the interface core section portion <NUM> of the embodiment of <FIG>.

Yet another example of an interface core section that includes an elbow connector is shown in <FIG>. The manifold section <NUM>-<NUM> includes an aperture at one side of the manifold section <NUM>-<NUM>. This aperture receives one end of an elbow connector <NUM>-<NUM> in use, the elbow connector <NUM>-<NUM> adapted to rotate freely relative to the manifold section <NUM>-<NUM>, the plane of rotation of the elbow connector aligned back-front of a user <NUM> in use, rather than side-side as in the embodiment of <FIG>.

The interface core section <NUM> also includes a pillow section <NUM>, the pillow section including pillows <NUM>-<NUM> which are adapted to substantially seal against the nares of a user in use. The pillow section <NUM> is fluidically connected to the manifold section <NUM>-<NUM> so that in use the heated, humidified gases stream enters the pillow section <NUM> from the manifold section <NUM> and passes through the pillows <NUM>-<NUM> into the nasal cavity of a user. 'Substantially seals' as it is used in this specification should be taken to mean that perfectly sealing against the nares with no leaks is the most desirable outcome. However, a small degree of leakage in use is almost certainly inevitable, and a person skilled in the art will understand that the phrase 'substantially sealing' is intended to indicate that a very small amount of leakage may sometimes, but not always, occur. As the pillows <NUM>-<NUM> are substantially sealed against the nares of a user, all or substantially all of the stream of gases which passes through the manifold section <NUM> and the nasal pillow section <NUM> will be delivered to a user.

As shown in the preferred embodiments of <FIG>, <FIG> and <FIG>, the pillow section <NUM> is composed of two main sub-parts that form a continuous or integrated whole in use: pillows <NUM>-<NUM>, which locate into the nares of the user or patient <NUM> in use, and a pillow manifold section or pillow gasket <NUM>-<NUM>, which is connected to the interface core section <NUM> in use, so that gases passing through the core section <NUM> in use will then pass into the pillow gasket <NUM>-<NUM> and from there into the pillows <NUM>-<NUM>.

In order to aid in sealing the nasal pillows <NUM>-<NUM> against the nares of a wide variety of users, each of whom will have differently shaped and sized nostrils, the pillows <NUM>-<NUM> are in the preferred form formed from a soft and supple material with a high degree of flexibility, such as silicone rubber or similar. Preferred forms of the nasal pillows <NUM> are described in detail below.

The nasal pillow section <NUM> can either be formed separately from the rest of the core portion <NUM>, or integrally formed with the core portion <NUM>. In the preferred embodiments as shown in <FIG>, <FIG> and <FIG>, the nasal pillow section <NUM> is a separate item to the core portion <NUM>.

The nasal pillow section <NUM> is formed from two main parts in the three preferred forms described herein: a base portion or nasal pillow gasket portion <NUM>-<NUM>, and nasal pillows <NUM>-<NUM>. The attachment or connection of the nasal pillow section <NUM> to the remainder of the core portion <NUM> is achieved by attaching the gasket portion <NUM>-<NUM> to the manifold portion <NUM>-<NUM>, with the pillows <NUM>-<NUM> preferably (although not always) integrally formed with the gasket portion <NUM>-<NUM>. The embodiments of <FIG>, <FIG> and <FIG> show this form of connection.

In the preferred embodiments, at least the pillows <NUM>-<NUM> are formed from a supple and flexible material, such as silicone rubber.

The first preferred form of pillow gasket portion <NUM>-<NUM> shown in <FIG> shall now be described with particular reference to <FIG> and <FIG>, <FIG> and <FIG>.

The preferred form of pillow gasket portion <NUM>-<NUM> includes an open lower face or open lower front portion <NUM> which corresponds in use to the open rear face (not shown) of the manifold section <NUM>-<NUM>, so that in use it acts as a gases aperture. It should be noted that the open rear face and the open lower portion <NUM> could be apertures - these do not have to cover the entire 'face'. In use, the perimeter of the open lower portion <NUM> of the pillow gasket portion <NUM>-<NUM> is connected to the open rear face of the manifold section <NUM>-<NUM>. The wall 237a which surrounds the open lower portion <NUM> slots or locates into the open rear face of the manifold section <NUM>-<NUM>, and substantially seals against it. It can be seen that all of the gases passing through the manifold section <NUM>-<NUM> will pass into the pillow gasket portion <NUM>-<NUM> and from there into the nasal pillows <NUM>-<NUM>. It should be noted that the pillow gasket portion <NUM>-<NUM> can be attached and removed repeatedly from the manifold portion <NUM>-<NUM> as required by a user. Optionally, if required, a key <NUM> can be formed into the wall section <NUM>, the key <NUM> slotting into a corresponding slot in the manifold section <NUM>-<NUM> to ensure the pillows are correctly oriented in use.

In the first preferred form of pillow gasket portion <NUM>-<NUM>, the pillow gasket <NUM>-<NUM> is shaped so that the two side portions are slightly angled towards one another. That is, the top surface which covers the open rear face of the manifold <NUM> appears to have a V-shape when viewed from the front, with the pillows <NUM>-<NUM> one on each of the two sub-surfaces or inner faces of the 'V'. The angle of the 'V' is not acute - each edge or plane of the 'V' of the pillow gasket portion <NUM>-<NUM> is raised by a few degrees only (e.g. <NUM>-<NUM> degrees). The pillows <NUM>-<NUM> are mounted one on each of the two planes, and are in this manner angled inwards towards one another slightly in the most preferred form (although there are of course many other ways in which this could be achieved without creating a `V'-shape).

In the preferred form, as described above, the nasal pillows <NUM>-<NUM> and the gasket portion <NUM>-<NUM> are formed as a one-piece item. However, the pillows <NUM>-<NUM> could be removably connected to the gasket portion <NUM>-<NUM>, either individually or as a pair. For example, the gasket portion <NUM>-<NUM> could include a pair of stub bases to which the pillows are press-fitted in use, the stub base and the base of the stem <NUM>-<NUM> being mutually adapted to connect together by way of a press-fit, a keyed connection, or similar. This would potentially allow pillows which are of different shapes or sizes to be fitted to the pillow gasket portion <NUM>-<NUM>. This would be advantageous if a user required pillows moulded specifically to the shape of their nares, or pillows of different sizes. This would also allow a range of standard pillows to be manufactured, the range having different sizes or different shapes, or both. This would provide a range of off-the-shelf adjustment.

In the very most preferred forms, the pillow gasket portion <NUM>-<NUM> is formed so that in normal use, the pillow gasket portion <NUM>-<NUM> is held off or apart from the upper lip of a user <NUM>, the intention being that there is no contact or minimal contact between the gasket portion and the lip of a user in use. When the phrase 'no contact' is used in this specification, it should be taken to mean that there is no intentional contact, and any contact that does occur is outside the intended normal operating condition of the interface. Surprisingly, and in contrast with what has previously been known in this area of the art, it has been found that minimising contact with the upper lip of a user is in certain circumstances beneficial. Some prior art devices have actively used the upper lip as a support for the pillow gasket portion, even in some cases going as far as to have a lower rear portion of the gasket which can be at least semi-inflated by the gases passing through the pillow gasket. It is intended in these designs that the inflated/inflatable lower rear portion acts as a lip cushion and aids in providing support.

Surprisingly however, it has been found that having a pillow gasket which minimises contact with the upper lip of a patient can also be beneficial for some users, and can act to increase the user's comfort levels and compliance with their therapy regime. Surprisingly, it has also been found that movement of a user's upper lip can in some cases have more of detrimental effect on the sealing of pillows against the nares of a user <NUM> than is known in the art at the present time, or was anticipated. Because this detrimental effect was not anticipated, it was not compensated for when designing the interfaces which are currently known in the art. It has been found that in some cases when using the prior art interfaces that movement of the user's lip causes an excessive amount of movement of the interface core portion and pillows - more than was originally anticipated for interface designs which include lip cushions. Therefore, when using the prior art designs, there is an increased likelihood that the seal between the nares of a user <NUM> and one or both of the pillows <NUM> will fail, at least momentarily. The pillows of the present invention offer a useful, new, and surprising alternative to the prior art, with contact between the pillows and the lip minimised as far as possible.

There are several different ways this minimised or no contact can be achieved. The preferred forms will now be described with particular reference to <FIG>, <FIG> and <FIG>.

In the first most preferred form as shown in <FIG>, the lower inner surface <NUM> of the pillow gasket portion <NUM>-<NUM> appears inwardly-sloping or concave when viewed directly from one side - the surface is formed to include a concavity. The concavity in this preferred form runs generally between an area at or close to the lower end or base of the stem <NUM> of the pillows <NUM>-<NUM>, and the rear of the wall 237a (however, it should be noted that the concavity could run between any convenient points - it does not have to be restricted to these points). This concavity ensures that contact between the users face and the pillow section <NUM> occurs only at the nasal pillows <NUM>-<NUM> during the majority of usage, and there is no contact in use with the upper lip of a user <NUM>, or that what contact does occur is minimised.

The critical dimensions of the very most preferred form are shown in <FIG>. Dimension line <NUM> on <FIG> shows the width dimension across the lower inner face <NUM> of the pillow section <NUM> for the very most preferred form, this being <NUM>. Dimension line <NUM> on <FIG> shows the preferred height of the face <NUM> between the base of the pillows <NUM> on the outer side, and the wall <NUM> for the very most preferred form, this being <NUM>. Dimension line <NUM> on <FIG> shows the preferred height of the face <NUM> between the base of the pillows <NUM> on the inner side, and the wall <NUM> for the very most preferred form, this being <NUM>. Dimension line <NUM> on <FIG> shows the inner curve of the concavity for the face, showing that the upper edge of the face <NUM> is <NUM> further forward than the lower edge of the face <NUM> in the most preferred form. It should of course be noted that these dimensions are the dimensions of the most preferred form, and a range of e.g. <NUM> and possibly up to <NUM> or more either side of these dimensions is possible.

The lower inner surface <NUM> could alternatively be a substantially straight planar surface running between the lower end or base of the stem <NUM> and the rear of the wall 237a. That is, this forward end or edge of the plane in the embodiment of <FIG> will be just behind the lowest part of the gases supply aperture <NUM>. However, concave is preferred for this first most preferred form, as this provides the most room for movement of the upper lip of a user <NUM> without contact occurring.

It can be seen that the planar surface will be at an angle to the vertical - it will be forward-sloping, with the lower edge forward of the rear edge, the angle of slope dictated to a great extent by the locations of the gases supply aperture of the manifold section, and the lower end or base of the stems. It should be noted that the plane does not have to begin and end at these positions, but it is preferred that the edges are substantially at these positions.

As shown in <FIG>, the first preferred form of pillows <NUM> also includes a bridging platform <NUM> which runs between the stems <NUM> of the pillows <NUM>-<NUM>. The bridging platform <NUM> helps to localise as much of the movement of the pillows to the region closest to the user's nares. This localisation of the movement assists in helping to avoid any leaks that may develop from the patient moving their lip while wearing the interface. The bridging platform <NUM> is an area between the pillows that is stiffer than the remaining material around the base of the stems <NUM>, the stems <NUM> themselves, and the caps <NUM> of the pillows. In the most preferred form, the bridging platform <NUM> is created by thickening an area - that is, using a thicker material in that area or section to increase the stiffness in that area. Surprisingly, it has been found that making the lower rear surface <NUM> concave as described above and also combining this with the bridging platform such as platform <NUM> provides unexpected benefits. The concave surface can be shaped in such a manner as to minimise contact between the user's lip and the surface <NUM>, and also so that the platform <NUM> is supported and movement of the pillows <NUM>-<NUM> is localised.

In the embodiment shown in <FIG>, the stems <NUM> are flared towards their top end, where the stems <NUM> meet and merge with the bottom of the caps <NUM>. It should be noted that if required, the stems <NUM> could alternatively be straight-sided, or at least not flared towards the top end.

The second most preferred form will now be described with reference to <FIG>. The second most preferred form is very similar to the first most preferred form described above with reference to <FIG>. However, as can be seen from <FIG>, the lower rear surface <NUM> or support structure <NUM> is very slightly outwardly sloped or slightly convex. In this context, slightly outwardly sloped or slightly outwardly bowed is defined as follows: the surface <NUM> never deviates more than <NUM> outwards from a straight line drawn between the two ends (i.e. if a straight line <NUM> were drawn between point A and point B on <FIG>, this line can be thought of as defining a plane passing across the rear of the actual pillow gasket portion <NUM>-<NUM>. For the actual pillow gasket portion <NUM>-<NUM>, stating that the surface <NUM> is slightly outwardly sloped means that there is never a deviation of more than <NUM> from the plane defined by line <NUM> for the actual pillow gasket portion <NUM>-<NUM> when it is manufactured.

In a similar fashion as for the first most preferred form described above with reference to <FIG>, the second preferred form also includes a bridging platform - bridging platform <NUM> - which runs between the stems <NUM> of the pillows <NUM>-<NUM>. The combination of the bridging platform <NUM> and surface <NUM> is similar to that described above: in combination these elements can be formed so that not only is contact between the lip of a user <NUM> and the interface minimised, but also the platform <NUM> is supported and movement of the pillows <NUM>-<NUM> is localised.

The third preferred form of pillow gasket will now be described with reference to <FIG> show a design that is very similar to that of <FIG>. This form or embodiment is slightly different to that shown in <FIG> as it has a bridging platform <NUM> that sits as far away from the lip as possible without compromising the localised movement of the pillows provided by the bridged platform design. This is achieved by including an indented profile <NUM> as part of the design. This has the surprising advantage that the inwardly sloping support face or concave face <NUM> in combination with the indented profile <NUM> of the bridging platform <NUM> will minimise contact between the elements of the interface and the face of a user, and still provide sufficient support.

It should be understood that there are several other design requirements for a patient interface, and in particular the interface core section and pillows, aside from increasing user comfort and compliance by minimising contact with the users upper lip (where this minimised contact is considered to be appropriate or beneficial). For example, as well as user comfort, there is the requirement that a good seal is formed between the pillows and the nares, that the pillows and gasket form an internal gases passageway that is of a size and shape to allow the passage of heated humidified gases without overly impeding the gases flow and without causing gases flow or pressure to be outside a desirable range, etc. A person skilled in the art, having access to the description relating to the preferred embodiments as outlined above and below, would be able to ascertain e.g. the exact dimension or shape which they require from within a suitable range, which would have the desired overall effect.

The second preferred form of pillow gasket is shown in <FIG>, and is described below with particular reference to <FIG>. This second preferred form shares many of the features of the first preferred form, including the three preferred forms of pillow gasket portion described above. That is, the pillow gasket portion <NUM>-<NUM> of this second preferred form can include features such as for example the surfaces <NUM>, <NUM> and <NUM> and the indented profile <NUM> as described above, and these are dimensioned in a similar fashion to the preferred form <NUM> described above. As described above, the manifold section <NUM>-<NUM> includes an aperture located at the front of the manifold section <NUM>-<NUM>, where an elbow connector <NUM>-<NUM> is connected to the manifold section <NUM>-<NUM>. The forward end or edge of the forward-sloping plane in the embodiment of <FIG> will be just behind the lowest part of this gases supply aperture.

The main difference between the pillow gasket portion <NUM>-<NUM> and the pillow gasket portion <NUM>-<NUM> is that the second preferred form of pillow gasket <NUM>-<NUM> is held in position on the manifold section <NUM>-<NUM> by a pair of protrusions <NUM> on the gasket portion <NUM>-<NUM> which slot into corresponding apertures on the manifold section <NUM>-<NUM>. In the form shown in <FIG>, the protrusions <NUM> and the apertures are aligned centrally on the manifold section <NUM>-<NUM> and the gasket portion <NUM>-<NUM>. However, this potentially allows the gasket portion <NUM>-<NUM> to be fitted upside-down on the manifold section <NUM>-<NUM>, so if required these can be offset to the sides, so that the gasket portion <NUM>-<NUM> can only be connected in one (correct) orientation.

A third preferred form of pillow gasket is shown in <FIG>, and is described below with particular reference to <FIG> and <FIG> and <FIG>.

The manifold section <NUM>-<NUM> and the main body of the gasket section <NUM>-<NUM> of the pillow section <NUM> of this third preferred form when assembled for use have the overall general form of a cylinder, which in use is aligned across the top lip of a user. The manifold section <NUM>-<NUM> includes an aperture at one side of the manifold section <NUM>-<NUM>, formed in the end section <NUM>-1b, the aperture adapted to receive one end of the elbow connector <NUM>-<NUM> in use. The elbow connector <NUM>-<NUM> and the manifold section <NUM>-<NUM> are adapted to rotate freely relative to each other in use, the plane of rotation of the elbow connector aligned back-front of a user <NUM> in use, rather than side-side as in the embodiment of <FIG>.

In this third preferred form, the pillow section <NUM> is removably attached to manifold section <NUM>-<NUM>. When the pillow section <NUM> and the manifold section <NUM>-<NUM> are connected, the two nasal pillows <NUM>-<NUM> extend outwards and upwards from the cylindrical main portion, towards the nares of a user <NUM> in use.

The manifold section <NUM>-<NUM> is formed from a semi-rigid plastic, with a central cross-brace body section <NUM>-1a, and two end sections <NUM>-1b and <NUM>-1c. A cap <NUM> closes off one end-end <NUM>-1c - in use (the opposite end from the elbow connector <NUM>-<NUM>).

The gasket section <NUM>-<NUM> of the pillow section <NUM> has the general overall form of a cylinder, the gasket section <NUM>-<NUM> and the manifold section <NUM>-<NUM> mutually sized so that the gasket section <NUM>-<NUM> slots between the end sections <NUM>-1b and <NUM>-1c. The gasket section <NUM>-<NUM> includes a slit <NUM> which runs along the length of the cylindrical body, at the bottom front of the cylindrical body, opposite the pillows <NUM>-<NUM>. In use, the slit <NUM> in the gasket section <NUM>-<NUM> is held closed by engagement of the edges of the slit with the cross-brace body section <NUM>-1a.

The ends of the headgear straps <NUM>/<NUM> in this third preferred form include connectors <NUM> which engage with the ends of the manifold section <NUM>-<NUM> to hold the manifold section and pillow section <NUM> in place on the face of a user in use.

In a similar manner to that described above for the first and second preferred forms or preferred embodiments, the lower rear part of the gasket section <NUM>-<NUM> can (if required) be rounded inwards in a concave fashion, so that there is no contact between the upper lip of a user <NUM> and the rear of the gasket portion <NUM>-<NUM> of the pillow section <NUM> of the third preferred form. One way in which this concavity can be achieved is shown in <FIG>, with the lower inner surface <NUM> concave or curved inwards. <FIG> shows one style of concavity, the surface <NUM> re-curving outwards at the lower part of the concavity, towards the bottom or lower portion of the gasket portion <NUM>-<NUM>. <FIG> shows a second style of concavity, with the lower part or portion of the surface <NUM> ending closer to the lower inner edge or side of the slit <NUM> than the first style shown in <FIG>.

In a similar manner to the first and second preferred forms, the concavity is intended to minimise contact in use with the upper lip of a user <NUM>. The lower inner surface <NUM> could alternatively be a straight planar surface running between the lower end or base of the stems <NUM> and the lower inner edge or side of the slit <NUM>, or another appropriate point or plane running across the rear of the gasket portion <NUM>-<NUM> - for example, the outer, lower edge of the planar surface could be substantially close to the lowermost point of the gases supply aperture formed in the end section <NUM>-1b (which is also substantially close to where the lower inner edge or side of the slit <NUM> is located). One `straight surface' example is shown in <FIG>. However, concave is preferred (as in <FIG> and <FIG>), as this provides the most room for movement of the upper lip of a user <NUM> without contact occurring.

A bridging platform (not shown) can also be used in a similar fashion to the bridging platforms <NUM>, <NUM>, <NUM> as described above in relation to the first and second gaskets. The bridging platform can include an indented profile if required, similar to that already described.

The stems <NUM> for this form are shown as flared towards their top end, where the stems <NUM> meet and merge with the bottom of the caps <NUM>. It should be noted that if required, the stems <NUM> could alternatively be straight-sided, or at least not flared towards the top end.

As described above, there are three particularly preferred forms of interface assembly, which have several common elements and several elements which are unique to that particular preferred form. Many different forms of pillow design can be used with the preferred embodiments described above. For example, the pillows shown in the preferred embodiments of <FIG> all have a single-walled cap <NUM> and a smooth-walled stem <NUM>, the stem flaring at the upper end, towards the cap <NUM>.

It should be noted that different designs of pillow can be used with the preferred forms of interface assembly as described above. For example, the stems or stalks <NUM> could be ribbed, as described in co-pending <CIT>.

Also, if required, pillows having a double-cap structure (an inner cap and an outer cap) could be used.

It should also be noted that a `single pillow' structure could be used, with one pillow or item delivering gas to the nostrils of a user - for example, a pillow structure with a single stem that bifurcates into two caps just below the nostrils, or a single cap shaped to deliver gas to both nostrils simultaneously, the single cap being fed a gases stream through either a single or a double stem. 'Nasal pillows' in this specification should be read as covering at least these different possible designs, and not just the paired stalk and cap arrangement described above. `Nasal pillows' in this specification should also, if appropriate, be taken to mean a nasal mask - for example, a silicone nasal mask fluidically connected to the gasket, the gasket in use being located underneath the nostrils of a user and in front of the upper lip of a user. The nasal mask ('nasal pillows') would extend from the gasket, covering around at least part of the outside surface of the nose of a user and substantially sealing against the skin of a user so that the stream of heated humidified gases is delivered to the nare of the user.

The features described above can be used individually or in any combination in the pillows and interface of the present disclosure.

'Supple' or 'flexible' as these words are used in this specification with reference to e.g. the nasal pillows should be taken to mean that the item can be substantially and repeatedly deformed - e.g. by a user pinching, squashing or crushing it in their hand, with the item returning to its original shape with little to no plastic deformation occurring. An item having a rectangular or square cross-section, with a thickness of <NUM>-<NUM>, a width of e.g. <NUM>, and a length of <NUM> or more, formed from a 'supple' or 'flexible' material as it should be understood in this specification, will, if held at one end, bend to an extent easily appreciable to the naked eye - i.e. it will bend at least <NUM>-<NUM>. The most preferred materials having 'supple' or 'flexible' properties as they should be understood within the context of this specification will, if formed in the manner referred to above, bend completely - that is, bending enough so that the unsupported end points substantially directly downwards. If the material does not bend to an appreciable extent, then it is a rigid or semi-rigid material for the purposes of this specification - see below. It should also be understood that 'flexible' is intended to mean a material that is soft, supple and flexible enough that an item formed with the dimensions outlined above (<NUM>-<NUM> x <NUM> x <NUM>) could be rolled into a solid tube (i.e. with no central `hollow' portion), and when the tube is unrolled there would be little to no plastic deformation of the material.

'Rigid' or 'semi-rigid' as it is used in this specification should be understood to mean that an item described in this manner can be elastically deformed, but that it would require application of an external force apart from gravity (i.e. more than its own weight) to do so - a 'rigid' or 'semi-rigid' item will not collapse or bend under its own weight, in any orientation. It is noted that all items usually described as rigid do have a certain degree of elasticity, but the elastic limit will normally be reached before the elastic deformation of the rigid material is appreciable to the naked eye. Glass, for example, will shatter before the average person is able to appreciate that it has elastically deformed at all. An item having rectangular or square cross-section, with a thickness of <NUM>-<NUM> and a length of up to <NUM>, formed from a 'rigid' or 'semi-rigid' material as it should be understood in this specification, will not bend to an extent easily appreciable to the naked eye. As an example, the arms of the Fisher & Paykel Opus™ interface or the ResMed Mirage Swift™ II interface are around <NUM>-<NUM> long and have a thickness of less than <NUM>. The arms of these devices are formed from a plastic having a rigidity so that they will not bend under their own weight if held at one end, and for the purposes of this specification can be considered to be 'rigid' or semi-rigid'.

'Substantially vertically downwards' as it is written in this specification should be interpreted as not necessarily meaning absolutely vertical - an angle of <NUM>-<NUM> degrees or more off-vertical lies within the meaning of `substantially vertical' as it is used in this specification.

It should also be noted that 'downwards', 'outwards', 'inner', 'outer', 'rear', 'front', and similar terms as they are used in this specification refer to the mask being worn by a user who is standing up. For example, 'inner' and 'rear' refer to that side of the interface nearest a users face in use. However, in use the interface is intended to be used by a user who is asleep and will be lying on a bed, either on their back, front or side. The convention referred to above (a user standing) has been adopted for ease of reference.

It should also be noted that the term 'interface' or `interface assembly' as it is used in this specification refers to any combination of the interface core section <NUM> (or <NUM>, <NUM> or <NUM>), the interface conduit <NUM> or supply conduit <NUM> (or both), and the headgear assembly <NUM> - that is, for the preferred embodiment, the term 'interface' could refer to the interface core section <NUM> with or without the headgear assembly <NUM>, and with or without the supply conduit <NUM>.

The terms 'swivel' and 'rotate' have their normal dictionary definitions. However, it should specifically be noted that as used in this specification, 'rotate' means that the item turns around an axis or centre point and movement is in a single plane. In contrast, 'swivel' as used in this specification should be taken to mean that the item is capable of movement in more than one plane.

Claim 1:
A nasal pillow section (<NUM>) for use as part of an apparatus for providing a stream of gases to a user, said pillow section (<NUM>) in use located in front of the upper lip and below the nostrils of a user, said pillow section (<NUM>) comprising, when viewed from the front and to one side of the nasal pillow section (<NUM>) being worn by the user who is standing up:
a pillow gasket (<NUM>-<NUM>), having a gases aperture which receives a stream of gases in use,
nasal pillows (<NUM>-<NUM>), fluidically connected to said pillow gasket (<NUM>-<NUM>) and adapted to substantially seal against the nostrils of a user in use, so that substantially the whole of said stream of gases passes into said nasal pillows (<NUM>-<NUM>) from said pillow gasket (<NUM>-<NUM>) and is delivered to said user,
the lower inner surface (<NUM>) of said pillow gasket (<NUM>-<NUM>) shaped to include a concavity or a straight planar surface;
wherein the pillow gasket (<NUM>-<NUM>) has the form of a cylinder which in use is aligned across the top lip of a user, the gases aperture being at one side of the pillow gasket (<NUM>-<NUM>).