Patent Description:
Respiratory masks are used to provide therapies for the treatment of a variety of respiratory conditions including but not limited to CPAP and NIV. The present disclosure will be described in relation to CPAP therapy, however it is to be understood that it may be equally applicable to other therapies.

CPAP therapy is used in the treatment of obstructive sleep apnea (OSA), a condition in which the back of the throat relaxes so much while sleeping that it narrows or entirely blocks the airway. With the constriction or closure of the airway, breathing can stop or become very shallow for a few seconds or longer. CPAP splints open the airway by providing a constant flow of pressurized air to the airway via an interface such as a mask. For the therapy to be effective, a substantially leak free seal ideally should be maintained between the mask and a user's face. In order to achieve this, a headgear system can be used to secure the mask to a user's face. It is commonly known in the art for there to be a headgear connection assembly between a headgear and a mask. The headgear connection may include a fastening means, such as but not limited to, hooks, loops and clips that allow the headgear to be selectively attached and detached.

Some characteristics that exist with prior headgear connection assemblies include fasteners being difficult to attach to and/or detach from the mask, fasteners detaching undesirably during use, resulting in leaks and/or loss of therapy, or fasteners providing too much or too little mobility in the connection between headgear and mask, which may impact the ease with which a mask is fitted and/or user comfort. These characteristics may lead to the mask and headgear system lacking a desirable level of ease of use, reliability and/or comfort, which in turn may result in less-than-ideal user compliance.

It is an objective of one or more embodiments disclosed herein to at least partially address one or more of these characteristics. Alternatively, it is an object to at least provide a useful choice to the public. <CIT>, <CIT> and <CIT> disclose mask assemblies with headgear connected to a mask by clips.

The present invention provides a mask assembly as defined in claim <NUM>.

According to a first aspect of the presently disclosed subject matter, there is provided a headgear connection assembly for a respiratory mask, the headgear connection including a clip and a clip attachment portion. The clip attachment portion includes a post and a clip receiving opening. The clip includes a hook configured to engage with the post, a headgear attachment loop, and one or more finger grips. The hook includes a central portion, two outer portions and an interference bump.

According to a second aspect of the presently disclosed subject matter, the clip attachment portion further comprises a stop bump configured to restrict unwanted rotation of the clip when assembled.

Further aspects of the presently disclosed subject matter, which should be considered in all its novel aspects, will become apparent to those skilled in the art upon reading of the following description which provides at least one example of a practical application of the invention.

In some configurations, a clip connector for connecting a headgear to a mask body includes a body portion configured for attachment to the headgear. A hook portion defines a U-shape having a first leg, a second leg and an entrance to a space between the first leg and the second leg. The hook portion can comprise a central portion, a pair of outer portions positioned on opposing sides of the central portion. Each of the central portion and the pair of outer portions define a portion of both the first leg and the second leg. An interference bump can be provided on at least one of the central portion and the pair of outer portions. The interference bump extends into the entrance to the space. The central portion and the pair of outer portions are configured to flex independently of one another.

In some configurations, a width of the entrance at the interference bump is smaller than a width of an attachment structure of the mask body configured to be received within the space of the hook portion.

In some configurations, only the central portion includes the interference bump and flexes to allow an attachment structure of the mask body to be introduced into the space of the hook portion.

In some configurations, only the outer portions include the interference bumps and flex to allow an attachment structure of the mask body to be introduced into the space of the hook portion.

In some configurations, at least the ones of the central portion and outer portions without the interference bump accommodates a tension force of the headgear in use.

In some configurations, a slot is provided between the central portion and each of the outer portions.

In some configurations, the slot extends through first leg and second leg of the hook portion.

In some configurations, the slots are filled with an elastic filler material.

In some configurations, the filler material is overmolded onto the clip connector.

In some configurations, at least one finger grip portion is disposed on the body portion. The finger grip portion can be formed from a soft or elastic material.

In some configurations, the soft or elastic material of the finger grip portion is overmolded onto the body portion.

In some configurations, the at least one finger grip portion comprises first and second finger grip portions on opposing edges of the body portion of the clip connector.

In some configurations, the central portion is more flexible than the outer portions.

In some configurations, a mask assembly includes a mask body comprising a post and an opening adjacent the post and a clip connector, such as any of the clip connectors described in the preceding paragraphs. The post can be configured to be received within the space of the hook portion of the clip connector. The mask body can comprise a limitation bump within the opening that contacts the clip connector to limit rotation of the clip connector relative to the mask body.

In some configurations, the limitation bump limits one or both of rotation about an axis of the post and rotation normal to the axis of the post.

In some configurations, the limitation bump is located on an upper edge of the opening.

In some configurations, a respiratory mask is configured to deliver pressurized gas to a user. The mask is configured to attach to headgear by a connector clip having a body portion and a hook portion. The respiratory mask comprises a post configured to be received within a space of the hook portion of the connector clip. An opening is adjacent the post. A limitation bump is associated with the opening and is configured in use to contact the connector clip to limit rotation of the connector clip relative to the mask.

In some configurations, the limitation bump is located on an upper side of the opening and in use limits upward rotation of the connector clip, but permits downward rotation and disconnection of the connector clip from the post.

In some configurations, a width of the opening is configured to be equal to or smaller than a width of the body portion.

In some configurations, the limitation bump is configured to contact the body portion of the clip to limit rotation.

In some configurations, the limitation bump limits forward rotation of the connector clip.

In some configurations, rotation is limited to no more than <NUM> degrees.

In some configurations, a respiratory mask assembly includes a headgear, a connector clip having a body portion and a hook portion, and a respiratory mask, such as any of the respiratory masks described in the preceding paragraphs. The connector clip is configured to connect the headgear to the mask. The body portion is connected to the headgear. The hook portion is narrower than the body portion.

In some configurations, a connector arrangement comprising a connector clip for connecting a headgear to a mask body includes an attachment portion disposed on one of the mask body and the connector clip. A deflectable hook is disposed on the other of the mask body and the connector clip. A width of an entrance of the deflectable hook is narrower than a width of the attachment portion. The attachment portion is inserted through the entrance of the deflectable hook to connect the headgear to the mask body. An interference bump is disposed on the deflectable hook and protrudes in a direction that narrows the entrance of the deflectable hook. The interference bump inhibits the attachment portion from exiting through the entrance.

The deflectable hook can be selectively attached over the attachment portion via an interference fit between the attachment portion and the deflectable hook to connect the headgear to the mask body.

The interference bump can extend along the entire width of the deflectable hook.

The deflectable hook can include a center hook portion positioned between, adjacent to, and in alignment with outer hook portions. The center hook portion can be flexible independent of the outer hook portions.

An interference bump can be disposed on the center hook portion and protrude in a direction that narrows the entrance into the deflectable hook. The interference bump can prevent the attachment portion from exiting through the entrance.

An interference bump can be disposed on each of the center hook portion and the outer hook portions and protrude in a direction that narrows the entrance into the deflectable hook. Each interference bump can inhibit the attachment portion from exiting through the entrance.

Slots can separate the center hook portion and the outer hook portions.

The slots can be filled with elastic material.

The deflectable hook can further comprise elastic material over-molded onto outer surfaces of the deflectable hook.

The attachment portion can further comprise a cylindrical column, wherein the deflectable hook attaches over the cylindrical column.

The center hook portion can be more flexible than the outer hook portions.

In some configurations, a connection system for connecting a headgear to a mask body includes an attachment portion disposed on the mask body. The attachment portion can further comprise an opening disposed on the mask body, and a post disposed along an outer extent of the opening. A connector is disposed on the headgear. The connector can further comprise a body portion and a deflectable hook portion. The deflectable hook portion of the connector can be selectively attached over the post to connect the headgear to the mask body. The attachment portion can further comprise at least one stop bump positioned adjacent to the post along an extent of the opening. The stop bump can protrude a distance into the opening. The at least one stop bump can contacts the connector and block rotation of the connector to prevent the connector from rotating and detaching from the post.

A width of the body portion along a direction parallel to an axis of the post when the deflectable hook portion is connected to the post can be greater than a width of the opening along the direction parallel to the axis of the post.

A width of the body portion along a direction parallel to an axis of the post when the deflectable hook portion is connected to the post can be greater than a width of the deflectable hook portion along the direction parallel to the axis of the post when the deflectable hook portion is connected to the post.

The body portion can contact the mask body to limit a range of rotation of the connector about the post.

The range of rotation of the connector about the post can be <NUM> degrees or less.

The at least one stop bump can be positioned along an upper extent of the opening.

The at least one stop bump can extend a distance into the opening that is greater than the difference between the width of the opening along the direction parallel to an axis of the post and the width of the body portion along a direction parallel to the axis of the post when the deflectable hook portion is connected to the post.

The body portion can contact the at least one stop bump to limit a range of rotation of the connector about the post.

An interference bump can be disposed on the deflectable hook portion and protrude in a direction towards a lower surface of the body portion. A distance between the interference bump and the lower surface of the body portion can be less than a width of the post.

The interference bump can extend along the entire width of the deflectable hook portion.

The deflectable hook portion can include a center hook portion positioned between, adjacent to, and in alignment with outer hook portions. The center hook portion can be flexible independent from the outer hook portions.

An interference bump can be disposed on the center hook portion and protrude in a direction towards a lower surface of the body portion. A distance between the interference bump and the lower surface of the body portion can be less than a width of the post.

An interference bump can be disposed on each of the center hook portion and the outer hook portions and protrude in a direction towards a lower surface of the body portion. A distance between each interference bump and the lower surface of the body portion can be less than a width of the post.

Slots can separate the center hook and the outer hooks.

The slots are filled with elastic material.

Finger grip portions can be disposed on the body portion. The finger grip portions can be formed from an elastic material.

The post can have a cylindrical cross-sectional shape.

The post can have a vertical orientation relative to the orientation of the mask body in use.

A protrusion can be disposed on the body portion and extend away from an outer surface of the body portion. The protrusion can contact the mask and limit rotation of the connector about the post to less than <NUM> degrees.

The deflectable hook portion can be narrower than the body portion.

Elastic material can be over-molded onto outer surfaces of the deflectable hook portion.

Also disclosed, but not independently claimed, is, a method for attaching a headgear to a mask body, in which the mask body has an attachment portion including an opening disposed on the mask body and a post disposed along an outer extent of the opening, the headgear having a connector including a body portion and a hook portion connected to the body portion, and the hook portion having an entrance that is narrower than a width of the post, the method comprising aligning an entrance of the hook portion with the post, inserting the post through the entrance of the hook portion, the hook portion deflecting in a direction away from the post as the post travels through the entrance of the hook portion, selectively securing the hook portion onto the post to connect the headgear and the mask body, the hook portion deflecting to an undeflected shape after the post has traveled through the entrance of the hook portion, the entrance narrowing to block the post from exiting through the entrance, and limiting rotation of the connector about the post via at least one stop bump positioned adjacent to the post along an extent of the opening, the stop bump contacting the body portion and blocking rotation of the connector beyond a range of rotation.

The method can further comprise limiting rotation of the connector about the post, the body portion contacting the mask body and blocking rotation of the connector beyond a range of rotation.

The body portion can limit the range of rotation of the connector about the post to <NUM> degrees or less.

The method can further comprise restricting rotation of the connector within the opening via at least one stop bump positioned adjacent to the post along an extent of the opening, the stop bump contacting and blocking rotation of the connector to prevent the hook portion from rotating and detaching from the post.

The at least one stop bump can limit the range of rotation of the connector about the post to <NUM> degrees or less.

Embodiments of the disclosure will now be described, by way of example only, with reference to the accompanying drawings in which:.

As used herein the term 'over-molded' may be used to refer to any injection molding process, such as co-molding or two-shot molding, that combines two or more separate materials to create a single part, wherein the separate materials are permanently bonded to each other.

<FIG> shows a perspective view of a respiratory mask <NUM> comprising a mask body <NUM>, a headgear <NUM> and a headgear connection assembly <NUM>. The headgear connection assembly <NUM> is configured to provide a means of easily connecting and disconnecting at least a portion of the headgear <NUM> to the mask body <NUM>. The headgear connection assembly <NUM> includes a clip <NUM> and a clip attachment portion <NUM>, wherein the clip <NUM> is configured to provide a connection between a headgear strap <NUM> and the clip attachment portion <NUM>. The clip attachment portion <NUM> can be defined by, carried by or attached to a portion of the mask, such as the mask body <NUM>.

<FIG> shows the clip attachment portion <NUM>. As shown, the clip attachment portion <NUM> is configured to be a part of the mask body <NUM>. The clip attachment portion comprises a post <NUM> and a clip receiving opening <NUM>. The post <NUM> is generally vertical, with respect to the orientation of the mask in use, when the user is sitting upright. However, the post <NUM> is not limited to a vertical position and may be oriented at various angles with respect to the orientation of the mask in use. The clip receiving opening <NUM> is forward of the post <NUM> (i.e., in a direction away from the user) and/or laterally inward of the post <NUM> (i.e., in a direction toward a centerline of the mask <NUM>. The post <NUM> provides a location for the clip <NUM> to attach or be retained to the mask body <NUM>.

The post <NUM> may be cylindrical in geometry (i.e., a circular cross-sectional shape) to allow easy connection of the clip <NUM> to the post <NUM>. The cylindrical geometry is also configured to allow rotation of the clip <NUM> around the post <NUM>. The post <NUM> is not limited to a circular cross-sectional shape and may include elliptical, polygonal, or a combination of several shapes. The cross-sectional shape of the post <NUM>, in combination with the shape of the clip <NUM>, may be configured to allow only a range of rotation of the clip <NUM> or bias the clip <NUM> towards preferred angles of rotation with respect to the post <NUM>, if desired. The clip receiving opening <NUM> provides an opening for at least a portion of the clip <NUM> to pass through the clip attachment portion <NUM> and connect or attach to the post <NUM>. This is just one configuration that can enable a clip <NUM> to be attached to a mask body <NUM>.

In another embodiment, the post <NUM> may be positioned or configured such that an opening <NUM> may be unnecessary. For example, the post <NUM> may be attached to the mask body but positioned a distance away from a surface of the mask body. The distance away from the mask body may provide clearance for the clip <NUM> to connect or attach to the post <NUM>. Other variations on geometry may provide improved functionality and will be described herein.

<FIG> show a non-limiting exemplary embodiment of the clip <NUM> which may be part of a mask assembly according to the invention. As shown, the clip <NUM> includes a hook <NUM>, an interference bump <NUM>, a central portion <NUM> and two outer portions <NUM>, a headgear attachment loop <NUM> and one or more finger grips <NUM>. The hook <NUM> is configured to fit around and attach to the corresponding post <NUM> of the clip attachment portion <NUM>. The hook <NUM> can have a first leg portion and a second leg portion defining a U-shape or J-shape in cross-section, for example, to define a space for receiving the post <NUM>. The first leg can be attached to the body portion of the clip <NUM> and the second leg can define a free end of the hook <NUM>. In some configurations, the cross-sectional shape of the hook <NUM> can allow the hook <NUM> to wrap around a majority of post <NUM>. However, the hook <NUM> is not limited to any specific cross-sectional shape. The hook <NUM> includes an inner surface <NUM>, which can be configured to be at least partially cylindrical to match the cylindrical geometry of the post <NUM>. The inner surface <NUM> is not limited to a partial cylindrical shape and may interface with the corresponding shape of the post <NUM>.

At the end of the hook <NUM>, the inner surface <NUM> can be connected to and/or merge into an interference bump <NUM> that is configured to narrow the hook entrance <NUM> relative to the diameter of the post <NUM>. When attaching the hook <NUM> to the post <NUM>, the hook <NUM> transitions from an undeflected state to a deflected state. In other words, the narrower hook entrance <NUM> created by the interference bump <NUM> requires the hook <NUM> to deflect outward in a direction away from the post <NUM> in order to widen the hook entrance <NUM> as the post <NUM> passes through the hook entrance <NUM>. When the post <NUM> has fully passed through the hook entrance <NUM> and the clip <NUM> and the clip attachment portion <NUM> are connected, the hook <NUM> transitions back toward or to the undeflected state and the hook entrance <NUM> narrows. The interference bump <NUM> can act as a stop that retains the clip <NUM> on the post <NUM> by inhibiting or preventing the post <NUM> from passing through the hook entrance <NUM> in response to relatively low forces, such as those typically encountered during normal use, but that allows deliberate disconnection.

Further, in at least some configurations, the interference bump <NUM> may contact the post <NUM> to provide an interference fit between the post <NUM> and the clip attachment portion <NUM> when hook <NUM> is attached to the post <NUM>. In addition or in the alternative, the hook <NUM> may have an inner diameter smaller than a diameter of the post <NUM> such that the hook <NUM> may have an interference fit with post <NUM>. Such arrangements can assist in retaining the clip <NUM> in a desired rotational position. However, an interference fit connection is not necessarily utilized in all embodiments. In some configurations, when the hook <NUM> is in an undeflected state, the inner surface <NUM> and the interference bump <NUM> may define a diameter that is larger than the diameter of the post <NUM>. With such an arrangement, the narrower hook entrance <NUM> created by interference bump <NUM> inhibits or prevents the post <NUM> from exiting through the entrance <NUM>, but the clip <NUM> might otherwise have a relatively loose fit on the post <NUM> to allow rotational and/or sliding movement of the clip <NUM> relative to the post <NUM>.

In the embodiment of <FIG>, the interference bump <NUM> has a constant geometry that extends along the width of the central portion <NUM>. In other embodiments, the geometry of the interference bump <NUM> may extend along the entire width of the hook <NUM>. Further, the geometry of the interference bump <NUM> and may be constant or varied along the width of the central portion <NUM> and/or the entire width of the hook <NUM>.

The clip <NUM> can be made from a substantially rigid material, such as, but not limited to, polypropylene, nylon or polycarbonate. This material selection will provide the clip <NUM> with the structural integrity to support at least normal or expected retention forces applied by the headgear <NUM> to the mask body <NUM>. The material is capable of some elastic deformation so that the hook <NUM> can deflect when being attached to the post <NUM>.

<FIG> and <FIG> show an end view and a plan view, respectively, of the clip <NUM>. It can be seen that the hook <NUM> comprises a central portion <NUM> and two outer portions <NUM>. The central and outer portions <NUM>, <NUM> can be configured to flex independently of each other. In one non-limiting exemplary embodiment, the central and outer portions are at least partially separated by one or more slots <NUM> (see also <FIG>). In the embodiment shown, the slots <NUM> extend through both sides of the U-shaped hook <NUM>, however, the length of the slots may be varied to provide a level of flexibility that enables an easy connection between the clip <NUM> and the clip attachment portion <NUM> whilst reducing or eliminating the likelihood of unwanted disconnection during use.

<FIG> shows a cross-sectional view of the clip <NUM> along a line 4A-4A in <FIG>. This view shows that, in one non-limiting exemplary embodiment, the interference bump <NUM> can be more pronounced or only located on the central portion <NUM> (see also <FIG>). As a result of the interference bump <NUM> reducing the size of the hook entrance <NUM> to a size that is narrower than the diameter of the post <NUM>, the central portion <NUM> may be configured to be more flexible than the outer portions <NUM> in order to deflect and allow the post <NUM> to move past the interference bump <NUM>. A portion or an entire length of the central portion <NUM> of the hook <NUM> may have a reduced cross-sectional thickness x, in comparison to corresponding locations of the outer portions <NUM>, which have a thickness of y. The reduced thickness may result in increased flexibility in the central portion <NUM>, which may allow it to deflect more readily when passing over the post <NUM>, thus improving ease of use. Alternatively, the width W, as shown in <FIG>, of the central portion <NUM> may be defined to provide the desired level of flexibility. The relatively thicker outer portions <NUM> can be more rigid or stronger than the central portion <NUM> and can accommodate or can be capable of accommodating a majority or a substantial entirety of the tension force of the headgear <NUM>. In some configurations, the portions <NUM> and <NUM> can have the same or approximately the same thickness. In some configurations, the outer portions <NUM> may not flex or may not be required to flex to allow the post <NUM> to enter the space of the hook <NUM> through the entrance <NUM>. The illustrated arrangement can also be reversed and the outer portions <NUM> can be thinner than the central portion <NUM> and/or can have interference bumps <NUM>, as shown in <FIG>. In such arrangements, the outer portions <NUM> can flex and the central portion <NUM> may not flex or may not be required to flex for the post <NUM> to enter the space of the hook <NUM> through the entrance <NUM>. Moreover, the entire arrangement can be reversed between the clip <NUM> and the mask body <NUM> such that the post <NUM> is defined or carried by the clip <NUM> and the hook <NUM> is defined or carried by the mask body <NUM>.

In another non-limiting exemplary embodiment, as shown in <FIG>, a clip <NUM> can comprise a substrate <NUM> and one or more over-molded portions <NUM>. The substrate <NUM> can comprise the functional features of the clip being the hook <NUM> and headgear attachment loop <NUM>. The substrate <NUM> can be made from a substantially rigid material as per the clip <NUM> of the previous embodiments. The over-molded portions <NUM> can be made from a soft and/or flexible material, such as, but not limited to, silicone rubber or a thermoplastic elastomer. The over-molded portions <NUM> can be configured to provide finger grips <NUM> on the sides of the clip <NUM>. The finger grips <NUM> may be non-slip and comfortable to hold.

In a further variation of this embodiment, shown in <FIG>, the hook <NUM> of the substrate <NUM> includes slots <NUM>. The slots <NUM> can be configured to provide flexibility to the hook <NUM> in the same way that the slots <NUM> have been previously described. In this embodiment, the slots <NUM> can also be configured to be filled with over-molded filler <NUM>. The over-molded filler <NUM> can be configured to be bonded to the surfaces of the slots <NUM>, thus providing a webbing-like structure between the central and outer portions <NUM> and <NUM> of the hook. The over-molded filler <NUM> can be made from a soft, flexible material that has at least some elasticity, such as silicone rubber or a thermoplastic elastomer; in some embodiments, the over-molded portions <NUM> and the over-molded filler <NUM> can be the same material. The flexible over-molded filler <NUM> allows the hook <NUM> to maintain the flexibility provided by the slots <NUM> whilst providing additional strength.

In an alternative embodiment (not shown), the outer portions <NUM> of the hook <NUM> may be created by an over-molding process. The outer portions <NUM> may have substantially the same geometry as the central portion <NUM> and be made of a material substantially the same as that described in relation to the over-molded filler <NUM>. The over-molded outer portions <NUM> can provide increased flexibility during attachment of the clip as a result of the more flexible material.

<FIG> demonstrates one of the modes of separation that can occur in conventional hook and post attachment configurations. The clip <NUM> can rotate upwards off the post <NUM> (i.e., in the direction indicated by the arrow). This rotation can occur when there is an upwards force applied to the headgear which causes the clip <NUM> to rotate and an upper portion of the clip <NUM> to rotate away from the post <NUM>. This can occur when a user moves his/her head whilst lying down or during fitting and adjustment of the mask. The upwards force and rotation of the clip <NUM> can result in the headgear <NUM> becoming detached from the mask body <NUM>. Disconnection of the headgear during use of the mask can result in a loss of therapy for the user.

<FIG> shows a non-limiting exemplary embodiment of a clip attachment portion <NUM> configured to address the aforementioned mode of separation. It can be seen that clip attachment portion <NUM> includes a stop bump <NUM> on its upper surface <NUM> (with respect to the orientation of the mask in use) when the user is sitting upright. The stop bump <NUM> is configured to be positioned adjacent to the post <NUM> and having a peak (lowermost point or portion) just forward of the clip <NUM> (i.e., away from the user) when the clip <NUM> is attached to the post <NUM>. This positioning is such that, when an upwards force is applied to the headgear or clip <NUM>, the clip <NUM> will come into contact with the stop bump <NUM> to stop rotation of clip <NUM>. This will limit any further rotation and reduce or minimize the likelihood of the clip <NUM> becoming detached from the post <NUM>. In at least some configurations, such an arrangement still permits movement of the clip <NUM> along the longitudinal axis of the post <NUM>. In at least some configurations, the stop bump <NUM> can permit downward rotation of the clip <NUM> to permit disconnection of the clip <NUM> from the post <NUM>.

The geometry of the stop bump <NUM> can be configured such that it does not impede the ability of a user to connect the clip <NUM> to the clip attachment portion <NUM>. This is achieved by the stop bump <NUM> not extending too far into the clip receiving opening <NUM>. The stop bump <NUM> may extend into the clip receiving opening <NUM> a distance that is close to, equal to or greater than a difference between the width of the clip receiving opening <NUM> along the direction parallel to an axis of the post <NUM> and the width of the clip <NUM> along a direction parallel to the axis of the post <NUM> when the clip <NUM> is connected to the post <NUM>. Further, the stop bump <NUM> is depicted as a rounded convex protrusion extending into the opening <NUM>. However, the stop bump <NUM> is not limited to any particular shape.

In further embodiments, there may be different stop bump <NUM> configurations. In one possible configuration, there may be more than one stop bump <NUM> in each clip attachment portion <NUM>. For instance, there may be stop bumps <NUM> on both the upper and lower surfaces of the clip attachment portion <NUM>. Each stop bump <NUM> may have a different size, shape and position to inhibit, limit or prevent rotation of the clip <NUM> while still allowing the clip <NUM> to be attached to the post <NUM>. In some configurations, vertical movement of the clip <NUM> along the longitudinal axis of the post <NUM> is permitted. In another configuration, there may be a single stop bump <NUM> located on the lower surface of the clip attachment portion <NUM>.

A further orientation of the clip <NUM> relative to the clip attachment portion <NUM> that can occur in conventional hook and post attachment configurations is shown in <FIG>. It can be seen that the clip <NUM> has been over-rotated on the post <NUM> such that it is directed in the opposite direction to which headgear retention forces need to be applied (i.e., away from the user). Over-rotation of the clip <NUM> on the post <NUM>, which can occur for example when the mask <NUM> is not fitted to a user, can make it difficult to fit the mask <NUM>, as the headgear <NUM> may lose its shape and the headgear straps <NUM> may tangle. Over-rotation of the clip <NUM> may also reduce the circumference of the headgear <NUM> and mask body <NUM> loop, thereby making the headgear <NUM> too small for the user and, thus, difficult to fit.

As shown in <FIG>, the stop bump <NUM> as described in relation to <FIG> is configured to limit rotation of the clip <NUM> on the post <NUM>. During rotation of the clip <NUM> on the post <NUM>, a surface <NUM> of the clip <NUM>, such as an outer and/or upper surface, can come into contact with the stop bump <NUM>, which limits, inhibits or prevents any further rotation of the clip <NUM> on the post <NUM>. In a preferred embodiment, the clip <NUM> and the stop bump <NUM> can be designed such that a maximum angle of rotation R may be up to approximately <NUM>° relative to a normal position of the clip <NUM> during use of the mask <NUM>. In other words, a maximum range of rotation of the clip <NUM> on the post <NUM> may be limited to approximately <NUM>° relative to a normal position of the clip <NUM> during use of the mask <NUM>. The size, shape and position of the stop bump <NUM> may be varied to vary the range of rotation of the clip <NUM> on the post <NUM>.

The clip embodiment of <FIG> and <FIG> provides an alternative non-limiting exemplary embodiment that may restrict or minimize over-rotation of the clip <NUM>. The hook <NUM> extends from a lower surface <NUM> of the clip body <NUM> at or near one end. The hook is substantially narrower than the clip body. <FIG> shows a rear view of the clip <NUM> or <NUM> attached to a clip attachment portion <NUM>. It can be seen that at least a portion of the clip body <NUM> is substantially the same width or, preferably, wider than the width W of the clip receiving opening <NUM>. The width of the hook <NUM> can be less than at least a portion of the body <NUM> such that the hook <NUM> can pass through a clip receiving opening <NUM> of the clip attachment portion <NUM> to attach to a post <NUM>. The clip body <NUM> width allows it to come into contact with the clip attachment portion <NUM> before rotating too far, as shown in <FIG> shows the clip <NUM> or <NUM> attached to a mask frame <NUM> viewed from above. The clip is rotated until the clip body contacts the clip attachment portion <NUM> and cannot rotate any further. In a preferred embodiment, the width of the clip body <NUM> and the width W of the clip receiving opening <NUM> can be designed such that the maximum angle of rotation R may be up to approximately <NUM>° relative to a normal position of the clip <NUM> during use of the mask <NUM>. In other embodiments, more or less rotation may be desirable. In alternative embodiments, there may be a bump or other suitable geometry on the clip <NUM> or <NUM> that limits rotation rather than width of the clip body <NUM>. Even further, the clip embodiment of <FIG> and <FIG> may also be combined with a stop bump on an upper surface <NUM> of the clip attachment portion <NUM>, as shown in <FIG>. When the clip body <NUM> is rotated on the post <NUM>, the clip body <NUM> contacts the stop bump <NUM> to limit rotation of the clip body <NUM>.

The claimed invention is defined by the claims. The disclosure may also be said broadly to consist in the parts, elements and features referred to or indicated in the specification of the application, individually or collectively, in any or all combinations of two or more of said parts, elements or features.

Claim 1:
A mask assembly comprising a headgear (<NUM>), a mask body (<NUM>, <NUM>) and a connection system for connecting the headgear (<NUM>) to the mask body (<NUM>, <NUM>), the connection system comprising:
an attachment portion (<NUM>, <NUM>) disposed on the mask body (<NUM>, <NUM>); and
a connector (<NUM>, <NUM>, <NUM>) disposed on the headgear (<NUM>);
wherein the attachment portion (<NUM>, <NUM>) comprises:
an opening (<NUM>, <NUM>);
a post (<NUM>) disposed along an outer extent of the opening (<NUM>, <NUM>); and
at least one stop bump (<NUM>) positioned adjacent to the post (<NUM>) along an extent of the opening (<NUM>, <NUM>), the stop bump (<NUM>) protruding a distance into the opening (<NUM>, <NUM>); and
wherein the connector (<NUM>, <NUM>, <NUM>) comprises:
a body portion (<NUM>); and
a deflectable hook portion (<NUM>, <NUM>);
wherein the deflectable hook portion (<NUM>, <NUM>) is configured to be selectively attached over the post (<NUM>) to connect the headgear (<NUM>) to the mask body (<NUM>, <NUM>), and the at least one stop bump (<NUM>) is configured to contact the connector (<NUM>, <NUM>, <NUM>) and block rotation of the connector (<NUM>, <NUM>, <NUM>) to prevent the connector (<NUM>, <NUM>, <NUM>) from rotating and detaching from the post (<NUM>).