Nasal mask interface assembly

Abstract

To provide an interface assembly for positive pressure therapy.SOLUTION: Interfaces can be used to provide respiratory gases to a user under positive pressure. In configurations where a nose of a user is covered, a nasal mask generally covers a bridge of the nose. Generally, a single seal will circumscribe a portion of the nose of the user. An interface assembly comprises a nasal mask that includes a seal having a curved portion. The curved portion of the seal curves to cover a portion of a clip that secures the seal to a frame. The frame has a ball-and-socket connection to a connector. The connector comprises an elbow having integrally formed vent holes and a swivel.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention generally relates to an interface assembly for positive pressure therapy. More particularly, the present invention relates to a nasal mask interface assembly and a headgear.

Background Art

[0002] An interface can be used to supply breathing gas to a user under positive pressure. In a configuration that covers the user's nose, a nasal mask generally covers the nasal bridge. Generally, a part of the user's nose is surrounded by a single seal.

[0003] Such a nasal mask is usually fixed to the user's face using a headgear having a T-joint frame connected to a seal member. In order to sufficiently reduce leakage, generally, a high pressure is applied to the user's nasal bridge in order to tighten the headgear. In other words, as the headgear is tightened, the load applied to the nasal bridge by the silicone seal generally gradually increases. Pressure can cause discomfort and in some cases can lead to pressure ulcers over time.

Summary of the Invention

Problems to be Solved by the Invention

[0004] An object of the present invention is to provide one or more configurations and / or methods that at least somewhat improve the above points or at least provide useful options for the general public or medical professionals.

Means for Solving the Problems

[0005] In one aspect, a seal member for an interface assembly includes a facial contact surface. The facial contact surface includes an edge that at least partially defines an opening. The facial contact surface also includes a first cheek surface and a second cheek surface. The first cheek surface includes a first thickness portion, and the second cheek surface includes a second thickness portion.

[0006] Preferably, the first and second thick portions are formed on the inner surface of the sealing member.

[0007] Preferably, the distal portion of the sealing member is overmolded onto the clip member. Preferably, the clip includes an element that receives a complementary element of the interface frame. Preferably, the clip member is tapered in the distal direction.

[0008] In one aspect, the sealing member for the interface assembly includes a facial contact surface. The facial contact surface includes an edge that at least partially defines an opening. The facial contact surface also includes an upper lip contact surface, a first cheek surface, and a second cheek surface. Sidewalls extend distally from the facial contact surface. The sidewalls include a first lower corner near the transition from the upper lip surface to the first cheek surface. The sidewalls include a second lower corner near the transition from the upper lip surface to the second cheek surface. The cross-sectional thickness of the first lower corner and the second lower corner is greater compared to the portion of the sidewalls located above the first lower corner and the second lower corner when viewed longitudinally.

[0009] Preferably, the distal portion of the sealing member is overmolded onto the clip member. Preferably, the clip includes an element that receives a complementary element of the interface frame. Preferably, the clip member is tapered in the distal direction.

[0010] In one aspect, the sealing member for the interface assembly includes a facial contact surface. The facial contact surface includes an edge that at least partially defines an opening. The facial contact surface also includes an upper lip contact surface, a first cheek surface, and a second cheek surface. Sidewalls extend distally from the facial contact surface. The sidewalls include a first thickened strip extending along a portion corresponding to the first cheek surface and a second thickened strip extending along a portion corresponding to the second cheek surface.

[0011] Preferably, the distal portion of the seal member is overmolded onto the clip member. Preferably, the clip includes an element that receives a complementary element of the interface frame. Preferably, the clip member is tapered in the distal direction.

[0012] Preferably, the cross-section of the distal side of the side wall of the seal member in the first and second wall thickness bands is thicker than the cross-section of the proximal side of the first and second wall thickness bands.

[0013] Preferably, the distal portion of the seal member is overmolded onto the clip member. Preferably, the clip includes an element that receives a complementary element of the interface frame. Preferably, the clip member is tapered in the distal direction.

[0014] In one aspect, the headgear for the interface assembly includes a body. A first lower strap and a second lower strap extend from the body in opposite directions of the body. A first upper strap and a second upper strap extend from the body in opposite directions of the body. The first lower strap includes a centerline of the first lower strap. The second lower strap includes a centerline of the second lower strap. The first upper strap includes a centerline of the first upper strap. The centerlines of the first and second lower straps intersect each other and then intersect the centerline of the first upper strap.

[0015] Preferably, the second upper strap includes a centerline of the second upper strap, and the centerline of the first upper strap corresponds to the centerline of the second upper strap.

[0016] Preferably, the intersection of the centerline of the first lower strap and the centerline of the second lower strap is offset by a distance of about 23 mm from the centerline of the first upper strap.

[0017] Preferably, the centerline of the first lower strap intersects the centerline of the first upper strap at a position about 43 mm from the position where the centerline of the second lower strap intersects the centerline of the first upper strap.

[0018] Preferably, the centerlines of the first upper strap and the second upper strap are correlated with each other and do not intersect the entire body of the headgear.

[0019] Preferably, the centerline of the first lower strap extends at an angle with respect to the centerline of the first upper strap, and this angle is from about 20 degrees to about 50 degrees.

[0020] In one aspect, the L-shaped tube used in the interface assembly includes a body having a proximal end and a distal end. The proximal end and the distal end form an angle with respect to each other, and a bent portion is defined at the transition from the proximal end to the distal end. The bent portion includes a plurality of ventilation holes. The plurality of ventilation holes are formed integrally with the body of the L-shaped tube.

[0021] In one aspect, the L-shaped tube used in the interface assembly includes a body having a proximal end and a distal end. The proximal end and the distal end form an angle with respect to each other, and a bent portion is defined at the transition from the proximal end to the distal end. The bent portion includes a plurality of ventilation holes. One or more of the ventilation holes include a first conical portion and a second trumpet-shaped portion.

[0022] Preferably, the first conical portion is the inner portion and the second trumpet-shaped portion is the outer portion.

[0023] Preferably, the ventilation holes are formed integrally with the body.

[0024] In one aspect, the interface assembly includes a frame, and a seal is detachably connected to this frame. The seal is configured according to any one of those described and / or illustrated in the present application.

[0025] In one aspect, the interface assembly includes a frame, and a headgear is detachably connected to this frame. The headgear is configured according to any one of those described and / or illustrated in the present application.

[0026] In one aspect, the interface assembly includes a frame to which a conduit connector is connected. The conduit connector includes an L-shaped tube configured according to any of those described and / or illustrated herein.

[0027] In one aspect, the interface assembly includes a frame to which a seal and a headgear are removably connected. The seal is configured according to any of those described and / or illustrated herein, and the headgear is configured according to any of those described and / or illustrated herein.

[0028] In one aspect, the interface assembly includes a frame to which a seal is connected and to which a conduit connector is connected. The conduit connector includes an L-shaped tube. The seal is configured according to any of those described and / or illustrated herein, and the L-shaped tube is configured according to any of those described and / or illustrated herein.

[0029] In one aspect, the interface assembly includes a frame to which a headgear is connected and to which a conduit connector is connected. The conduit connector includes an L-shaped tube. The headgear is configured according to any of those described and / or illustrated herein, and the L-shaped tube is configured according to any of those described and / or illustrated herein.

[0030] In one aspect, the interface assembly includes a frame to which a seal and a headgear are connected and to which a conduit connector is connected. The conduit connector includes an L-shaped tube. The seal is configured according to any of those described and / or illustrated herein. The headgear is configured according to any of those described and / or illustrated herein. The L-shaped tube is configured according to any of those described and / or illustrated herein.

[0031] In this specification, when reference is made to a patent specification, other external documents or other information sources, this is generally intended to provide a background for explaining the features of the present invention. Unless otherwise specifically stated, such reference to external documents should not be construed as an admission that such documents or such information sources are prior art or part of the common general knowledge in the art in any jurisdiction.

[0032] Here, the above and other features, aspects, and advantages of the present invention will be described with reference to the drawings of the preferred embodiments, which are for illustrative purposes only and are not intended to limit the present invention.

Brief Description of the Drawings

[0033]

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DETAILED DESCRIPTION OF THE INVENTION

[0034] The interface 20, constructed and configured in accordance with certain features, aspects, and advantages of the present invention, can, for example, but not limited thereto, improve the provision of CPAP therapy. In particular, the closed interface 20 exhibits improved sealing characteristics, while on the other hand, it can limit the pressure exerted on the user's nasal bridge.

[0035] Overview of the System Of course, the interface 20 can be used with any delivery device used in general respiratory management, for example, with a ventilator. However, the closed interface 20 will be described in relation to its use in a humidified CPAP system. The delivery system can also be in the form of VPAP (Variable Positive Airway Pressure), BiPAP (Bilevel Positive Airway Pressure), or other forms suitable for use in respiratory therapy.

[0036] Of course, while the various features, aspects, and advantages of the patient interface 20 are described in relation to a nasal mask, they can also be used with other interface configurations, for example, but not limited thereto, an oro-nasal mask or a full-face mask that seals around the user's nose and mouth, a mouth mask that seals around the user's mouth, and a nasal pillow or other types of masks that seal below the user's nose.

[0037] Referring to FIG. 1, a humidified continuous positive airway pressure (CPAP) system 22 is shown. The CPAP system 22 in the figure supplies humidified, pressurized gas to the user U through an interface 20 connected to a humidified gas transport path, i.e., an intake conduit 24.

[0038] The intake conduit 24 is connected to an outlet 26 of a humidification chamber 30 configured to contain a certain amount of water 32. The intake conduit 24 may include a heating device (not shown), for example, but not limited thereto, a heating wire or the like. The heating device can reduce the condensation of the humidified gas in the intake conduit 24 by heating the wall of the intake conduit 24.

[0039] The humidifying chamber 30 is preferably formed from a plastic material and may have a high thermal conductivity base (e.g., an aluminum base) that is in direct contact with the heater plate 34 of the humidifier 36. The humidifier 36 uses a controller 40 or the like. The controller may include, for example, but is not limited to, a microprocessor-based controller that executes computer software instructions stored in a related memory.

[0040] The controller 40 receives input instructions from a plurality of input sources including a user input interface 42 (e.g., a dial). The user input interface 42 allows a user U to set a predetermined value (e.g., a preset value) for the humidity, temperature, or other characteristics of the gas supplied to the user. The controller 40 may also receive input from other input sources. For example, in the configuration of the figure, temperature and / or flow rate sensors 44, 46 connected through a connector 50 can communicate with the controller 40. In addition to this, a temperature sensor 52 for the heater plate can communicate with the controller.

[0041] In response to a combination of user-set humidity or temperature values and other inputs that can be entered via the user interface 42, the controller 40 determines when and / or how much energy should be supplied to the heater plate 34 to appropriately heat the water 32 contained in the humidifying chamber 30. When a certain amount of water 32 in the humidifying chamber 30 is heated, water vapor begins to fill the space above the water surface of the water 32 in the humidifying chamber 30. The water vapor exits from the outlet 26 of the humidifying chamber 30 and exits along with the flow of gas (e.g., air) supplied from a gas supply device 54 (e.g., a blower) and entering the humidifying chamber 30 through an inlet 56.

[0042] The gas supply device 54 preferably includes an air flow generator 60, which may be a variable speed fan or may include a variable pressure regulator. In the configuration of the figure, the air flow generator 60 includes a variable speed fan. The air flow generator 60 preferably sucks air or other gas from the inlet 62. The air flow generator 60 is controllable, for example, but not limited to, by the controller 64 or by the controller 40. The controller 64 may control the fan speed, regulated pressure or others according to any suitable criteria. For example, the controller 64 may respond to an input from the controller 40 and user set values (e.g., preset values) of pressure and / or fan speed that can be set by the user interface 66 (e.g., a dial).

[0043] Patient interface Referring to FIGS. 2 and 3, the interface 20 generally includes a mask assembly 100. The mask assembly 100 generally includes a frame 102, a seal 104, and a clip 106 used to fix the seal 104 to the frame 102. The mask seal 104 and the clip 106 can be formed separately and combined, or, depending on the configuration, the mask seal 104 and the clip 106 can be integrated into a single component. In the configuration of the figure, the mask seal 104 is overmolded on the mask seal clip 106. The connector 108 connects a breathing conduit (not shown) to the mask frame 102.

[0044] Here, referring to FIG. 4, the seal 104 is shown from the back, which is the surface that is applied to and carried on the user's face. The seal 104 includes a facial contact surface 110. As shown in FIG. 4, the facial contact surface 110 preferably includes an edge 112 that at least partially defines an opening 114. In the configuration of the figure, the edge 112 surrounds the opening 114. The opening 114 is designed such that at least the lower part and the tip of the user's nose can enter. Preferably, the opening 114 is generally T-shaped, but inverted T-shaped.

[0045] The facial contact surface 110 generally includes a lip surface 120 configured to contact the user's face at a position below the nostrils and above the boundary of the red lips. The facial contact surface 110 also includes two separate cheek surfaces 122 that extend between the lip surface 120 of the facial contact surface 110 and the cross-section 124 of the facial contact surface 110. The cheek surfaces 122 can contact the inner surface of the user's cheek and / or the outer surface of the user's nose. The cross-section 124 extends to cover the user's nose and can connect the two cheek surfaces 122. Other configurations are possible.

[0046] As shown in the cutaway perspective view of FIG. 5, the facial contact surface 110 preferably includes the portion where the cross-section of the material is thinnest within the seal 104. Advantageously, the facial contact surface 110 can be easily deformed to closely adhere to one or more of the contours of the user's face, such as the upper lip, inner cheek, outer nose, or nasal bridge. Advantageously, since the cross-section of the facial contact surface 110 is thin at the portion covering the user's lips, it has high elasticity, and as a result, the pressure applied to the area above the user's lips is minimized. The seal 104 can be of any suitable configuration. In the illustrated embodiment, the seal 104 is inflatable. Thus, the facial contact surface 110 is pressed against the user's face by the pressure contained within the seal 104.

[0047] Referring again to FIG. 4, the illustrated seal 104 also includes two thickened panels 130, which are shown in hidden lines. The panels 130 are generally positioned along the upper portion of the cheek surface 122, near the transition from the cheek surface 122 to the cross-section 124. The panels 130 can be formed on the inner surface of the seal 104. The panels 130 represent locally thickened regions, which have been found to enhance the sealing ability of the seal 104. Currently, the panels 130 are thought to increase the lateral pressure against the outer surface of the user's nose, thereby making the pressure from the seal 104 fit more precisely to the shape of the user's nose. In other words, the panels 130 create a pinching effect against the outside of the user's nose, allowing the pressure from the seal 104 to fit more precisely to the shape of the user's nose.

[0048] Referring to FIGS. 5 and 6, the inner surface of the seal 104 further includes at least one thickened strip 132. Although one thickened strip 132 is shown in FIGS. 5 and 6, depending on the configuration, two or more thickened strips or thickened regions can be provided with the desire to achieve the characteristics provided by the thickened strip 132 in mind.

[0049] The thickened strip 132 in the figure is positioned along the side wall 134 of the seal 104. The side wall 134 extends forward from the face contact surface 110. The strip 132 preferably includes a larger lower region 136 inside each side of the seal 104 and a thinner connecting rib 140 that extends between the lower regions 136 by wrapping around the upper portion inside the seal 104. When the seal 104 receives pressure from the system 22, the thickened strip 132 helps to reduce the possibility and / or the degree to which the side wall 134 bulges outward. Bulging of the side wall 134 outward can cause unwanted deformation of the seal 104, which may adversely affect the performance of the seal 104.

[0050] Referring to FIG. 5, the side wall 134 preferably includes a thinner proximal portion 142 (i.e., closer to the user's face) and a thinner distal portion 144 (i.e., farther from the user's face). The thinner proximal portion 142 is connected to the thinner distal portion 144 by the thickened strip 132. Preferably, the face contact surface 110 forms a flange that curls inward from the proximal portion 142 of the meat wall. More preferably, the face contact surface 110 is tapered as it moves away from the proximal portion 142 of the side wall 134.

[0051] Continuing to refer to FIG. 5, the distal portion 144 curls inward toward the clip 106 at the shoulder portion 146. Depending on the configuration, the distal portion 144 curls inward toward the edge 150 at the shoulder portion 146. In the configuration of the figure, the edge 150 is overmolded together with a part of the clip 106.

[0052] The combination of the shoulder portion and the thin distal portion 144 and the thickened band portion 132 causes the seal 104 to exhibit a bending motion similar to that disclosed in U.S. Provisional Patent Application No. 61 / 476,188, filed Apr. 15, 2011; U.S. Provisional Patent Application No. 61 / 504,295, filed Jul. 4, 2011; U.S. Provisional Patent Application No. 61 / 553,067, filed Oct. 28, 2011; U.S. Provisional Patent Application No. 61 / 553,872, filed Oct. 31, 2011; and International Patent Application No. PCT / IB2012 / 000858, filed Apr. 13, 2012, the entire disclosures of which are hereby incorporated by reference herein. The bending motion is shown somewhat schematically by the dashed line in FIG. 6 and is indicated by the reference letter R. The distal portion of the seal 104 can pivot about the hinge point H, during which the most distal portion curves and protrudes in the region of the shoulder portion, which is shown by the curved portion R indicated by the dashed line in FIG. 6.

[0053] The shorter radius of the thin distal portion 144 and the shoulder portion 146 helps to control buckling and bending of the seal 104. In addition, when pressure is received from the system 22, the internal pressure reduces the likelihood that the seal will become immobile in the curved region and makes the bending motion more likely to occur. Further, the hardened band portion 132 extends downwardly toward the hinge point H, but need not extend below the hinge point H. The hardened band portion 132 also functions to limit the extent to which the distal portion 144 can curve and deform. Therefore, the distal portion 144 can curve only until the thickened band portion 132 abuts the edge 150.

[0054] In addition, by positioning the thin proximal portion 142 between the hardened band portion 132 and the facial contact surface 110, the thin proximal portion 142 can be somewhat deformed during wearing of the mask assembly 100. Preferably, the thin proximal portion 142 can be deformed somewhat further forward than the distal portion 144. The bending effect improves comfort for the user. Advantageously, due to the bending effect, the shape of the seal 104 can be varied to accommodate various nasal bridge heights while keeping changes in loading to a minimum.

[0055] Referring to FIG. 7, a graph of test data showing the differences provided by the bending effect is shown. Two masks, namely a prior art nasal mask sold under the trade name Zest™ by Fisher & Paykel Healthcare, were compared with a prototype mask having a bending effect. The deformation of the mask in the nasal bridge region was shown with respect to the force required to cause the deformation. As shown in the figure, throughout the range of deformation amounts, the prototype mask remained well below 1.5 N, while the prior art mask exceeded 4 N in the same deformation range. Further, as shown in FIG. 7, at any deformation distance, the prototype mask was much lower than the prior art mask. Therefore, for the prototype mask, the total force from the undeformed state to the maximum displacement was about 1 N. Further, the force increment received in the last 7 mm (for example, displacement from 13 mm to 20 mm) was less than about 0.3 N.

[0056] Referring to FIGS. 17 - 23, an alternative embodiment of the interface assembly 100 includes a seal 104 having at least one lower wall thickness band 300 in addition to, or instead of, the wall thickness band 132. Except for the at least one lower wall thickness band 300 and other features described hereinafter, the interface assembly 100 of FIGS. 17 - 23 is the same as, or similar to, the interface assembly 100 of FIGS. 2 - 16. Thus, the same reference numerals are used to denote the same or corresponding components or features in both embodiments. Referring particularly to FIG. 20, preferably the lower wall thickness band 300 is provided in addition to the wall thickness band 132. The lower wall thickness band 300 is disposed within the lower portion of the seal 104 and preferably below the lower half of the seal 104 and / or below the wall thickness band 132. The wall thickness band 300 is positioned along the lower portion of the side wall 134 of the seal 104 and preferably generally or substantially aligns with the wall thickness band 132 in the front - to - rear direction. However, in other configurations, the bands 132, 300 may be offset from each other in the front - to - rear direction. In other alternative configurations, some or all of the wall thickness band 132 and / or 300 may be disposed generally or substantially in a horizontal plane when the seal 104 is upright (the orientation shown in FIG. 20). In some such configurations, one or more wall thickness bands 132 and / or 300 may extend generally or substantially in the lateral direction of the seal 104. For example, one wall thickness band 132 or 300 may be provided, which, depending on the configuration, may be generally or substantially on the centerline of the seal 104. Alternatively, two or more wall thickness bands 132 or 300 may be provided, which may be spaced above and below the centerline of the seal 104, for example. Further, a combination of one or more generally or substantially lateral bands and one or more generally or substantially longitudinal or circumferential bands may be provided.

[0057] The illustrated band 300 preferably includes a larger upper region 302 on the inside of each side of the seal 104 and a thinner connecting rib 304 extending between the larger upper portion 302. The upper region 302 and / or the connecting rib 304 are preferably similar in shape to the lower region 136 and rib 140 of the band 132. However, in the illustrated configuration, the band 300 is scaled somewhat smaller than the band 132, which corresponds to the lower portion of the seal 104 being somewhat thinner (in the front-to-back direction) than the upper portion of the seal 104. Preferably, the band 300 performs substantially similar or the same function as the band 132. For example, the band 300 preferably reduces the likelihood and / or extent to which the sidewall 134 bulges outward, thereby causing the lower portion of the seal 104 to exhibit a bowing action in a similar or the same manner as described above with respect to the band 132.

[0058] 8, three cross sections are shown in the lower right portion of the seal 104 of the figure. The lowest cross section, near the corner of the seal 104 of the figure, is labeled with the reference letter A. A slightly higher cross section is labeled with the reference letter B, and an even higher cross section is labeled with the reference letter C. As shown, the middle cross section B is substantially thicker than the two adjacent cross sections A and C. The three cross sections A, B, and C are relatively close to each other, and have a wide variation in thickness to allow for better distribution of loads on the user's face.

[0059] Currently, it is considered that the user's face can withstand a greater load or pressure in certain areas compared to other areas. Increasing the thickness of the inner wall 134 allows the force to be better transmitted from the clip 106 to the face contact surface 110 through the side wall 134. Similarly, decreasing the thickness of the side wall 134 reduces the force transmitted between the clip 106 and the face contact surface 110 through the side wall. Depending on the configuration, it is considered that the user's face can withstand pressure in the upper jaw area just below the zygomatic process. For this reason, the lower corner region 152 includes a thicker region (e.g., Region B). Connecting to the forehead contact point provided by the frame 102, a triangular support portion can be defined between the two lower regions 152 of the seal 104 and the forehead contact point. The triangular support portion provides a stable base on the face, which can assist in resisting dislodgment during use.

[0060] To permanently attach the seal 104 to the clip 106, an overmolding method can be used. Referring to FIG. 9, the clip 106 is shown in a state where the seal 104 is not attached. The clip 106 can be formed of any suitable rigid or semi-rigid material. In one configuration, the clip 106 is formed of a polycarbonate material. Since the seal 104 is preferably formed of a silicone material and the clip 106 is formed of a polycarbonate material, by providing a retaining structure 160 on the clip 106, the seal 104 is fixed to the clip 106 by overmolding. In other words, since the silicone material of the seal 104 generally does not adhere to the polycarbonate material of the clip 106, the seal 104 is held on the clip 106 by securely locking the silicone material around the elements of the retaining structure 160.

[0061] The retaining structure 160 of the clip 106 is formed at the proximal end 162 of the clip 106. The retaining structure 160 in the figure is formed integrally with the clip 106, but these two can also be formed separately and joined together in any suitable way. However, the integrated structure improves manufacturability and the finished product is more durable.

[0062] The retaining structure 160 includes a plurality of struts 164 that define a plurality of slots 166. Preferably, the struts 164 are spaced along a circumferential surface 168 that defines an opening 170 at the proximal end of the clip 106. More preferably, the struts 164 are spaced substantially evenly along the circumferential surface 168. Even more preferably, the struts 164 are spaced along the circumferential surface 168 such that the ratio of the struts 164 to the intervening slots 166 is about 1:2. This 1:2 ratio has been found to maximize the connection strength between the seal 104 and the clip 106.

[0063] Continuing to refer to FIGS. 9 and 10, the retaining structure 160 preferably includes at least one distal surface 172 and at least one proximal surface 174, which are generally parallel to each other. In the illustrated configuration, at least one distal surface 172 includes an annular surface that surrounds the proximal end 162 of the clip 106, while at least one proximal surface 174 includes the plurality of ends of the struts 164. The parallel surfaces 172, 174 serve to minimize compression and resulting distortion due to the clamping force received during the overmolding process.

[0064] Further, as shown in FIGS. 9 and 10, the slots 166 are generally surrounded by a ring 176. In the illustrated configuration, the ring 176 surrounds the outside of the struts 164 at the distal ends of the struts 164. Other configurations are also possible. However, the illustrated configuration provides an easy-to-manufacture configuration.

[0065] Referring to FIG. 10, the distal end 180 of the clip 106 is configured to be attached to the frame 102. Preferably, the clip 106 is easy to attach to and remove from the frame 102, facilitating cleaning of the clip 106 and the seal 104 attached thereto. More preferably, the distal portion 180 is made to be in a sealed state with the surface of the frame 102. Even more preferably, the distal surface 182 is made to be in close contact with the surface of the frame 102.

[0066] Continuing to refer to FIG. 10, the distal portion 180 of the clip 106 includes one or more depressions 184. Preferably, the depressions 184 are also designed to be in close contact with the frame 102. In particular, the thin frame 102 includes one or more protrusions 190 that extend rearwardly towards the clip 106. Advantageously, these protrusions fit into the depressions 184 of the clip 106 to provide a snug fit and to thin the assembly 100.

[0067] Referring to FIGS. 3 and 11, the frame 102 and the clip 106 are preferably interconnected in an airtight, i.e., sealed relationship. In the configuration of the figure, the frame 102 includes a mounting boss 192 that extends towards the clip 106. The mounting boss 192 includes an outer surface 194 around which the inner surface 196 of the distal end 180 of the clip 106 slides. Preferably, the connection between the boss 192 and the distal end 180 of the clip 106 is a tapered fit. More preferably, the connection includes a medical taper of 1:40, which provides a mating surface that minimizes leakage between the two components. Even more preferably, the tapered connection includes an interference fit with a travel distance of 2 mm when measured from the back surface 200 of the frame 102 to the distal surface 182 of the clip 106. The outer surface 194 of the boss 192 in the figure and the inner surface 196 of the distal end 180 in the figure are generally cylindrical, although other shapes are possible.

[0068] Referring to FIGS. 17 - 23, an alternative interface assembly 100 includes an improvement to the detachable attachment configuration between the clip 106 and the frame 102. In particular, the attachment boss 192 includes intermittent, i.e., discontinuous, walls along its circumference. Preferably, the proximal end (i.e., the end closest to the user) includes at least one, preferably a plurality of recesses or notches 310, which extend towards the distal end of the attachment boss 192, facilitating the connection of the clip 106 to the frame 102. In particular, due to the notches 310, while assembling the clip 106 to the frame 102, the wall portion of the boss 192 between the notches 310 bends inwards, effectively reducing the diameter of the attachment boss 192. In the illustrated configuration, the notches 310 are generally or substantially triangular, and four notches 310 are provided. However, the notches 310 may be of other shapes (e.g., generally or substantially rectangular, square, trapezoidal, semi - circular) and numbers (e.g., 2, 3, 5, 6 or more). In addition to this, preferably, the notches 310 are unevenly spaced along the circumference of the attachment boss 192. In the illustrated configuration, the notches 310 are arranged as an upper pair and a lower pair, and the circumferential distance between the individual notches 310 of the upper and lower pairs is smaller than the circumferential distance between one of the notches 310 of the upper pair and the adjacent notch 310 of the lower pair. Preferably, in other respects, the attachment boss 192 of the interface assembly 100 in FIGS. 17 - 23 is similar to the attachment boss 192 of the interface assembly 100 in FIGS. 2 - 16, including, for example, a tapered fit.

[0069] The clip 106 and the frame 102 of FIGS. 17 - 23 may preferably also include an interference fit or an interlock configuration 320, which serves to hold the connection between the clip 106 and the frame 102 and / or increases the force required to separate the clip 106 from the frame 102. In such a configuration, preferably, the likelihood that the clip 106 and the frame 102 will accidentally or undesirably separate is reduced. Preferably, one of the clip 106 and the frame 102 includes at least one protrusion, and the other of the clip 106 and the frame 102 includes at least one recess sized and shaped to receive the protrusion. In the illustrated configuration, the clip 106 includes a pair of protrusions 322 and the frame 102 includes a complementary pair of recesses 324, although this configuration can be reversed. Preferably, the protrusions 322 are disposed above and below the inner surface 196 of the distal end 180 of the clip 106, and the recesses 324 are disposed above and below the outer surface 194 of the mounting boss 192 of the frame 102. In the illustrated configuration, the protrusions 322 and the recesses 324 are in diametrically opposed positions, each being circumferentially long along their respective surfaces 196 and 194, maximizing the length of the interference fit or interlock surface, thereby preventing separation of the frame 102 and the clip 106 and tending to minimize the axial length.

[0070] Preferably, the frame 102 of the interface assembly 100 of FIGS. 17-23 includes at least one recess 330, where the distal portion 180 of the clip 106 fits during use. In the illustrated configuration, the frame 102 includes a pair of recesses 330 that are positioned on either side of the mounting boss 192 and interact with the clip 106 to prevent or inhibit rotation of the clip 106 with respect to the frame 102. Preferably, the lower end of the recess 330 is positioned near the mounting boss 192, and the upper end of the recess 330 extends laterally outwardly and laterally from the mounting boss 192. Compared to the clip 106 of FIGS. 2-16, at least a portion of the wall thickness of the circumference of the distal portion 180 of the clip 106 of FIGS. 17-23 is thinner. The clip 106 of FIGS. 17-23 transitions to a thicker portion at the shoulder 332, which defines a surface 334 that faces distally. Preferably, in addition to the distal surface 182 contacting the frame 102, the surface 334 contacts the end surface 336 of the recess 330 as shown in FIG. 19, which helps to seal between the clip 106 and the frame 102. In addition to this, the contact between the surface 334 and the end surface 336 can define a complete connection position between the clip 106 and the frame 102. The shoulder 332 can be defined by the recess 184 of the clip 106 and thus extends over the same extent as the recess 184. The engagement of the recess 184 and the recess 330 can prevent or inhibit rotation of the clip 106 with respect to the frame 102. In other configurations, the shoulder 332 can surround a longer distance than the recess 184, or one shoulder 332 can surround the entire distal portion 180.

[0071] Referring to FIGS. 3 and 11, the boss 192 preferably surrounds an inner surface 202 that defines a socket for the ball connection 204 with the connector 108. In the illustrated configuration, the connector 108 generally includes an L-shaped tube 206 and a swivel 210. The swivel 210 can be used to connect to the intake conduit 24 or other breathing tube. Preferably, the L-shaped tube 206 is connected to the frame 102 by a joint defined by the ball 204 and the socket 202, while the swivel 210 is connected to the L-shaped tube by a cantilevered projection configuration 212.

[0072] According to the joint defined by the ball 204 and the socket 202, preferably, a limited range of pivotal movement is possible. Depending on the configuration, the ball 204 can pivot up to approximately 30 degrees with respect to the socket 202. Other ranges of pivotal movement can be defined as desired.

[0073] In the configuration of the figure, the ball 204 is pushed into the socket 202 of the frame 102 from the side having the back surface 202 of the frame 102. In other words, the L-shaped tube 206 is connected through the socket, and the ball 204 is pushed into the socket 202 for engagement. In such a configuration, the L-shaped tube 206 is less likely to be easily removed from the frame 102 by the user.

[0074] On the other hand, the swivel 210 is designed to be easily removable from the L-shaped tube 206. Preferably, the swivel 210 can rotate 360 degrees with respect to the L-shaped tube 206 around its axis, and the swivel 210 can be axially removed from the L-shaped tube 206 with a force of only about 30 N. Further, the connection between the L-shaped tube 206 and the swivel 210 is preferably designed to reduce leakage at the connection. In the configuration of the figure, the leakage is maintained at about 0.05 to about 0.4 L / min at 10 cmH2O.

[0075] Referring to FIG. 3, the distal end 214 of the L-shaped tube 206 preferably includes two or more notch regions or depressions 216. The depressions 216 can be of any suitable shape. In the configuration of the figure, the depressions 216 have a semi-circular shape, which extends upward into the distal end 214 of the L-shaped tube 206. The distal end 214 of the L-shaped tube 206 also includes at least one protrusion 220, preferably two or more protrusions 220. Preferably, each of the protrusions 220 extends along an arc of approximately 70 degrees. More preferably, each of the protrusions 220 is generally centered between the two depressions 216, and each of the protrusions 220 extends around the outer surface of the distal end 214 of the L-shaped tube 206 for approximately 70 degrees.

[0076] The swivel 210 preferably has a generally cylindrical shape. As shown in FIG. 3, the swivel 210 has an inwardly extending rib 222. The rib 222 preferably extends around the entire inner circumference. Depending on the configuration, the rib 222 may have an interruption. However, preferably, the rib 222 does not have an interruption large enough to accommodate the entire projection 220, whereby the rib 222 and the projection 220 cooperate to hold the swivel 210 in a state attached around the distal end 214 of the L-shaped tube 206. When assembling the swivel 210 to the L-shaped tube 206, the recess 216 causes the projection 220 to bend inwardly, whereby the projection 220 slides along the rib 222 and then snaps back outwardly to secure the projection 220 under the rib 222. For this purpose, the distance from the shoulder portion 224 (see FIG. 12) to the apex of the projection 220 (shown as X in FIG. 12) is substantially equal to or slightly greater than the distance from the proximal end 226 of the swivel (see FIG. 3) to the lower edge of the rib 222.

[0077] Referring now to FIG. 12, the L-shaped tube 206 preferably includes a plurality of vent holes 230 formed integrally. The vent holes 230 can be formed in a separate insert fixed to the L-shaped tube 206, but forming the vent holes 230 integrally results in a more aesthetically pleasing appearance and simplifies the assembly of the interface assembly 100. The vent holes are preferably formed in the surface of the L-shaped tube 206, i.e., on the outside of the bend from the proximal end where the ball 204 is located towards the distal end 214. Other configurations are possible.

[0078] Referring to FIG. 13, the vent hole 230 preferably comprises a configuration consisting of two parts. One or more proximal ends 232 of the vent hole 230 form a conical depression leading to the inner surface 234. In other words, one or more proximal ends 232 of the vent hole 230 include a dish-shaped surface. One or more distal ends 236 of the vent hole 230 include a trumpet-shaped surface. In other words, one or more distal ends of the vent hole 230 include a part of the shape of an hourglass. Preferably, the conical shape of the proximal end 232 and the trumpet shape of the distal end 236 are generally axially aligned, characterized by a smooth transition between the two shapes. More preferably, all or substantially all of the vent holes 230 have this configuration. Even more preferably, all or substantially all of the vent holes 230 are generally parallel to each other.

[0079] Continuing to refer to FIG. 13, the proximal end 232 of the vent hole 230 preferably defines a conical surface which, when viewed in cross-section, is substantially parallel to the axial center line CL of the proximal end of the L-shaped tube. In other words, the axial center line CL is generally related to the direction in which the die or insert is inserted and removed during manufacturing. More preferably, when viewed in cross-section, the proximal end 232 of the vent hole has at least one side wall (when viewed in cross-section) which, when viewed in cross-section, generally extends parallel (see reference line PL) or is generally oblique with respect to the parallel direction and, as it moves in the proximal direction (i.e., as the proximal end 232 widens), the surface deviates from the parallel direction. Thus, the proximal ends 232 of all or substantially all of the vent holes 230 can be formed from one insert, and at the same time, the insert can be easily pulled out. Depending on the configuration, the insert or die can be pulled out from the distal end 214 of the L-shaped tube, and the surface of the vent hole 230 is appropriately configured in accordance with such an insertion and removal direction of the insert.

[0080] Preferably, the wall thickness (i.e., the distance between the inner surface 234 and the outer surface 240) is about 1.5 mm. In such a configuration, the proximal end 232 (i.e., the conical portion in FIG. 14) is about 0.5 mm, while the distal end 236 (i.e., the trumpet-shaped portion in FIG. 14) is about 1.0 mm. Other dimensions and configurations are possible. The configuration of the figure is known to appropriately reduce the noise level associated with the air flow exiting the ventilation hole 230.

[0081] Referring again to FIG. 2, one or more headgear clips 250 are shown as being attached to the frame 102. In the configuration of the figure, two headgear clips 250 are fixed to the frame 102. The frame 102 generally includes ears 252, which are associated with each headgear clip 250. The ears 252 preferably extend generally laterally outward from the inner surface 202 that defines a socket for the L-shaped tube 206.

[0082] As shown in FIG. 15, each of the ears 252 includes a strut 254, while each of the clips 250 includes a hook 256. The hook 256 and the strut 254 provide a configuration that can be easily connected and disconnected. Preferably, since the clip 250 is symmetric, one clip can be used on both the left and right sides of the frame 102.

[0083] Depending on the configuration, a slight interference can be provided between the hook 256 and the strut 254 to reduce the possibility that the hook 256 accidentally disengages during use. Depending on the configuration, the hook 256 and the strut 254 can be shaped such that they are easier to remove from the hook 256 at a specific angular orientation around the strut 254 (for example, by pivoting the hook 256 away from the seal 106 around the strut 254, it can be made easier to remove from the shape of the strut 254). Further, since the hook 256 is pivotable with respect to the strut 254, the angular orientation of the clip 250 with respect to the frame 102 can be changed to make it easier to accommodate differences in head shape.

[0084] Each clip 250 includes a slot 260 defined through a main body 262 of the clip 250. The slot 260 is sized and configured to receive a lower strap 264 of the headgear assembly 266. Preferably, the lower strap 264 is passed through the slot 260 and folded back. More preferably, the lower strap 264 includes a hook-and-loop fastener such that the lower strap 264 is passed through the slot 260, folded back, and secured to itself. Other configurations may also be used.

[0085] The headgear assembly 266 also includes a pair of top straps 270 and a pair of upper straps 272. The top straps 270, upper straps 272, and lower strap 264 preferably converge at a main body 274. Further, each of the straps 264, 270, 272 preferably has a tab 276 that forms a part of a hook-and-loop fastener at its end. The tab 276 can be ultrasonically welded to the ends of the straps 264, 270, 272.

[0086] The straps 264, 270, 272 and the body 274 together define the headgear assembly 266. Depending on the configuration, the headgear assembly has a three-layer structure that includes layers formed of Lycra, foam, and UBL (unbroken loop) material. Advantageously, the UBL material provides a surface to which the tab 276 can be adhered. Depending on the configuration, the thickness of the three-layer structure is about 4 mm.

[0087] The uppermost strap 270 can be connected to a buckle, which is generally positioned at the top of the head. When combined with the buckle, the uppermost strap 270 generally defines a crown strap. The upper stop 272 is passed through a slot 280 formed in the T-joint portion of the frame 102 (see FIG. 2), and the lower strap 264 is passed through the clip 250 as described above. Depending on the configuration, the slot 280 in the T-joint portion of the frame 102 has a slit in the material defining the slot 280, whereby the loop defined by the upper strap 272 can be attached to and detached from the frame 102, whereupon the tab 276 need not be separated from the portion of the strap 272 to which the tab 276 is attached by a hook-and-loop fastener.

[0088] In an alternative interface configuration 100 of FIGS. 17 - 23, the slot 280 defines an opening 340 at its lower end and has a closed end 342 at its upper end. In particular, a central portion 344 of the frame 102 extends along the inside of the slot 280 and transitions to an upper portion 346 that defines the closed end 342 of the slot 280. An outer portion 350 extends along the outside of the slot 280 and has a tab 352 that extends inwardly at its terminus, which extends towards the central portion 344 but ends before reaching it, and the opening 340 of the slot 280 is defined. The upper closed end 342 prevents the upper strap 272 from coming off the frame 102 in an upward direction, and the tab 352 prevents the upper strap 272 from coming off the frame 102 unintentionally or undesirably in a downward direction.

[0089] The body 274 is preferably defined as a region that interconnects with various straps 264, 270, 272 and is tapered (narrower towards the straps 264, 270, 272), serving as a region to reinforce the intersection of the straps 264, 270, 272. The body 274 can be configured to be positioned below the external occipital protuberance of the parietal bone of the head. Such positioning when worn by the user reduces the movement of the headgear assembly 266 when the user turns their neck. Further, when the straps are attached, a three-dimensional configuration is obtained by the generally linear strap configuration. In other words, as shown in FIG. 16, the lower strap 264 extends substantially linearly from the body 274. Therefore, generally, the centerline LS extends along each of the lower straps 264. Similarly, as shown in FIG. 16, the upper strap 272 also extends substantially linearly from the body 274. Therefore, generally, the centerline US extends along both upper straps 272. In the configuration of the figure, the centerline US does not intersect the entire body 274. In other words, a part of the body is offset from and does not intersect the centerline US. Depending on the configuration, generally, the centerline LS is positioned at an angle with respect to the centerline US. Preferably, this angle is between about 20 degrees and about 50 degrees.

[0090] In the configuration of the figure, the centerline LS of the lower strap intersects at a position between the body 274 and the centerline US of the upper strap. Depending on the configuration, the centerline LS of the lower strap intersects on the same side of the centerline US of the upper strap where the lower strap 264 is positioned. Depending on the configuration, the intersection point of the centerline LS of the lower strap is offset by a distance N from the centerline US of the upper strap. Preferably, the distance N is about 23 mm. Depending on the configuration, the centerline LS of the lower strap intersects the centerline US of the upper strap at a position separated by a distance M. Preferably, the distance M is about 43 mm. Other configurations are also possible.

[0091] Although the present invention has been described with respect to specific embodiments, other embodiments that will be apparent to those skilled in the art are also within the scope of the present invention. Therefore, various changes and improvements may be made without departing from the spirit and scope of the present invention. For example, the positions of various components may be changed as desired. Further, not all of the features, aspects, and advantages are necessarily required for the practice of the present invention. Accordingly, the scope of the present invention is to be defined solely by the following claims.

Claims

Claim 1 A nasal mask interface assembly for positive pressure therapy, comprising a frame, and a seal including a facial contact surface defining an opening for receiving at least a lower portion and a tip of a patient's nose, said seal being formed from a silicone material, said seal; and a clip formed of a rigid or semi-rigid material used to secure said seal to said frame, said seal and said clip being formed separately and being capable of being secured together, said clip; and a conduit connector for connecting a breathing conduit to said frame, said conduit connector comprising an elbow and a generally cylindrical swivel removably and rotatably connected to a distal end of said elbow, said conduit connector; and comprising said frame includes a mounting boss defining an outer surface of a generally cylindrical boss, said mounting boss surrounding an inner surface of the boss defining a socket for ball connection to said conduit connector; said clip includes a generally cylindrical inner surface of the clip adapted to slide on said outer surface of the boss of said mounting boss for removably mounting said clip to said frame; a proximal end of said elbow includes a ball received in said socket of said frame to allow a limited range of pivotal movement relative to said frame; one of said clip and said frame includes at least one protrusion, and the other of said clip and said frame includes at least one recess sized and shaped to receive said protrusion, said at least one protrusion and said at least one recess providing an interlock configuration to assist in maintaining a connection between said frame and said clip; said frame further includes a pair of recesses disposed on both sides of said mounting boss for receiving a distal portion of said clip in use and interacting with said clip to prevent rotation of said clip relative to said frame, each of said pair of recesses having a first end and a second end, said first end being located near said mounting boss, and each of said pair of recesses extending from said first end to said second end so as to be laterally away from said mounting boss; a nasal mask interface assembly. Claim 2 The facial contact surface includes a first cheek surface and a second cheek surface, the first cheek surface includes a first thick portion, and the second cheek surface includes a second thick portion. The nasal mask interface assembly according to claim 1.

3. The facial contact surface includes an upper lip surface, a first cheek surface, and a second cheek surface. A side wall extending distally from the facial contact surface includes a first lower corner portion adjacent to a transition portion from the upper lip surface to the first cheek surface and a second lower corner portion adjacent to a transition portion from the upper lip surface to the second cheek surface. The first lower corner portion and the second lower corner portion include a thicker cross section compared to a portion of the side wall located vertically above the first lower corner portion and the second lower corner portion. The nasal mask interface assembly according to claim 1 or claim 2.

4. The frame includes the at least one protrusion, and the clip includes the at least one recess. The nasal mask interface assembly according to any one of claims 1 to 3.

5. The at least one protrusion includes a pair of protrusions facing each other in the diameter direction, and the at least one recess includes a pair of recesses facing each other in the diameter direction. The nasal mask interface assembly according to any one of claims 1 to 4.

6. The clip includes a holding structure integrally formed with the clip for holding the seal to the clip, and the seal is securely locked around an element of the holding structure. The nasal mask interface assembly according to any one of claims 1 to 5.

7. The frame further includes a T-piece portion extending upward from the mounting boss to provide a forehead contact point. The nasal mask interface assembly according to any one of claims 1 to 6.

8. The T-piece portion includes a pair of slots, the pair of slots are adapted to receive each of the headgear straps, and each slot has a cut in the material defining the slot, whereby the loop of the headgear strap can be attached and detached without being returned. The nasal mask interface assembly according to claim 7.

9. The opening of the seal has an inverted T shape. The nasal mask interface assembly according to any one of claims 1 to 8.

10. The nasal mask interface assembly according to any one of claims 1 to 9, wherein at least a part of the generally cylindrical inner surface of the clip has a wall thickness smaller than that of the remaining part of the generally cylindrical inner surface of the clip.

11. The nasal mask interface assembly according to any one of claims 1 to 10, wherein the elbow has at least one protrusion, the swivel has a ridge extending inwardly, and the at least one protrusion and the ridge extending inwardly cooperate to keep the swivel attached to the distal end of the elbow.

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