WO2008030831A2

WO2008030831A2 - Headgear assembly

Info

Publication number: WO2008030831A2
Application number: PCT/US2007/077573
Authority: WO
Inventors: Peter Chi Fai Ho
Original assignee: Ric Investments, Llc
Priority date: 2006-09-07
Filing date: 2007-09-05
Publication date: 2008-03-13
Also published as: JP2010509942A; JP5384345B2; EP2066192A2; EP2066192A4; US20110072553A1; WO2008030831A9; WO2008030831A3

Abstract

A headgear assembly (30, 150, 180) for attaching an object to a head of a user is defined by first (32, 152, 182) and second (34, 154, 184) beams adapted wrap around the back of a user's neck and/or head. The first and second beams are generally planer and are adapted to be disposed in a first plane responsive to being stretched flat. The first beam has a first radius of curvature defined in the first plane, and the second has a second radius of curvature defined in the first plane in a same direction as the first radius of curvature. A first member coupling the first beam with the second beam. When donned by the user, the headgear assembly assumes a generally spherical shape that conforms to the back of the human head.

Description

HEADGEAR ASSEMBLY PRIORITY CLAIM

[01J Under the provisions of 35 U.S.C. § 119(e), this application claims the benefit of U.S. provisional patent application serial no. 60/842,741, filed September 7, 2006.

TECHNICAL FIELD

[02] The present invention generally relates to a headgear adapted to support an object on the head of a user, and, more particularly, to a headgear having curved beams that enable the headgear to assume a spherical configuration when donned by a user.

BACKGROUND OF THE INVENTION

[03] There are numerous situations where it is necessary to couple an object to the face of a user. For example, non-invasive ventilation and pressure support therapies involve the placement of a patient interface device, which is typically a nasal mask that covers the nose, a nasal/oral mask that covers the nose and mouth, or full face mask that covers the patient face, on the face of a patient. The patient interface device interfaces the ventilator or pressure support device with the airway of the patient, so that a flow of breathing gas can be delivered from the pressure/flow generating device to the airway of the patient. Typically, non-invasive ventilation involves providing ventilatory gas to the airway of a patient without intubating the patient or surgically inserting a tracheal tube in their esophagus. Pressure support therapies involve providing a pressure, such as a continuous positive airway pressure (CPAP) or variable airway pressure, which varies with the patient's respiratory cycle (bi-level pressure support) or with the condition of the patient (auto-titrating pressure support), to treat a medical disorder, such as sleep apnea syndrome, in particular, obstructive sleep apnea (OSA), or congestive heart failure.

[04] It is known to maintain such masks on the face of a wearer by a headgear having upper and lower straps, each having opposite ends threaded through connecting elements provided on the opposite sides and top of a mask. Because such masks are typically worn for an extended period of time, it is important the headgear maintain the mask in a tight enough seal against a patient's face without discomfort. [05] One such headgear is disclosed in U.S. Patent No. 5,517,986 ("the '986 patent"), which is assigned to Respironics, Inc. of Pittsburgh, PA, the assignee of the present application. The headgear taught by the '986 patent includes a cap-like headpiece adapted to fit the crown and back of a patient's head. Lower straps provide a two-point connection with a gas delivery mask. Straps depending from the headpiece are connected to and moveable relative to the lower straps. Additionally, a pair of upper straps can be used to provide a four-point connection with the gas delivery mask if needed.

[06] Another such headgear also manufactured by Respironics, Inc. includes five straps extending in a star-like manner from a rear joining piece, which is positionable along the rear portion of a patient's head. The three uppermost straps are adapted to fit on the patient's head. A center top strap extends from the joining piece across the top of the patient's head to the patient's forehead. Upper side straps, which are provided on either side of the top strap, extend from the joining piece along the sides of a patient's head above the ears to attach to the top strap at the patient's forehead. The top strap includes a pair of elongated openings through which the upper side straps are threaded.

[07] Other conventional headgear include the Deluxe Patient Interface Headgear and the SimpleStrap™ Patient Interface Headgear, both of which are manufactured and sold by Respironics, Inc. of Pittsburgh, PA, the assignee of the present application. Deluxe Patient Interface Headgear and the SimpleStrap Patient Interface Headgear both include a strait (linear) top strap and a strait (linear) bottom strap that wrap around the head/neck of the user. The top and bottom straps are parallel to one another.

[08] These and other conventional headgear provide a convenient attachment of the patient interface device to the user's head. However, they may not optimize the comfort of the headgear on the head/neck of the user. They may also not maximize the stability of the headgear so that the patient interface device is securely mounted on the user. Therefore, a need exists for a headgear that is easy to use and adjust, is comfortable, provides a stable support for the object being attached to the user, and does not rest significantly on his or her hair.

DISCLOSURE OF THE INVENTION

[09] Accordingly, it is an object of the present invention to provide a headgear that overcomes the shortcomings of conventional headgear. This object is achieved according to one embodiment of the present invention by providing a headgear assembly for attaching an object to a head of a user. The headgear assembly includes a first beam and a second beam, both of which are adapted to wrap around a back of a user's neck or a back of a user's head. The first beam is generally planer and is adapted to be disposed in a first plane when the headgear assembly is stretched flat. When in this position, the first beam has a first radius of curvature defined in the first plane. The second beam is also generally planer and is adapted to be disposed in the first plane when the headgear assemblies is oriented in a flat position. The second beam has a second radius of curvature defined in the first plane in a same direction as the first radius of curvature. In addition, a first member couples the first beam with the second beam. By providing the first and second beams with a curve in this manner, the headgear assembly assumes a generally spherical shape, at least in the portion that extends over the back of the user's head/neck. This provides a headgear that better forms to the human anatomy, making the device comfortable and stable. [10] These and other objects, features, and characteristics of the present invention, as well as the methods of operation and functions of the related elements of structure and the combination of parts and economies of manufacture, will become more apparent upon consideration of the following description and the appended claims with reference to the accompanying drawings, all of which form a part of this specification, wherein like reference numerals designate corresponding parts in the various figures. It is to be expressly understood, however, that the drawings are for the purpose of illustration and description only and are not intended as a definition of the limits of the invention. As used in the specification and in the claims, the singular form of "a", "an", and "the" include plural referents unless the context clearly dictates otherwise.

BRIEF DESCRIPTION OF THE DRAWINGS

[11] FIG. 1 is a plan view of a portion of a first embodiment headgear assembly according to the principles of the present invention;

[12] FIG. 2 is a perspective view of the headgear portion shown in FIG. 1 ;

[13] FIG. 3 is a plan view a headgear assembly that includes the portion shown in FIG. 1 ; [14] FIG. 4 is a plan view of the headgear assembly of FIG. 3 showing the operation of the coupling members and including reinforcing members; [15] FIG. 5 is a plan view of a portion of a second embodiment of a headgear assembly according to the principles of the present invention;

[16] FIG. 6 is a perspective view of the headgear portion shown in FIG. 5;

[17] FIG. 7 is a plan view of a portion of an alternative configuration for the second embodiment of the headgear assembly; [18] FIG. 8 is a perspective view of a coupling member and associated components; [19] FIG. 9 is a plan view of a third embodiment of a headgear assembly according to the principles of the present invention; [20] FIG. 10 is a plan view of a fourth embodiment of a headgear assembly according to the principles of the present invention; [21] FIG. 11 is a plan view of a fifth embodiment of a headgear assembly according to the principles of the present invention; [22] FIG. 12 is a plan view of a sixth embodiment of a headgear assembly according to the principles of the present invention; [23] FIG. 13 is a perspective view of a seventh embodiment of a headgear assembly according to the principles of the present invention; [24] FIG. 14 is a side view showing the headgear assembly of FIG. 13 being worn by a user; and [25] FIG. 15 is a view showing a headgear assembly according to the principles of the present invention with an optional cross-bar.

DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS

[26] FIGS. 1-4 illustrate an exemplary first embodiment of a headgear assembly

30 and portions thereof according to the principles of the present invention. Headgear assembly 30 includes a first beam 32 and a second beam 34, both of which are adapted to wrap around a back of a user's neck or a back of a user's head. When the headgear is worn by the user, first beam 32 is closer to the top of the head than the second beam, which is closer the neck. Thus, the first beam is also considered the "top" beam and the second beam is considered the "bottom" beam relative to their respective orientation on the user.

[27] First beam 32 and second beam 34 are generally planer, i.e., are relative thin, and are flexible or semi rigid. As such, when the headgear assembly is stretched flat, they are disposed in a first plane. In other words, when the headgear assembly is lying flat, such as on a flat surface, the first beam and the second beam also lie flat on that surface. First beam 32 is curved along its length such that it has a first radius of curvature Rl defined in the first plane. Second beam 34 is also curved with respect to its lengthwise axis such that it has a second radius of curvature R2 that is also defined in the first plane. The first radius of curvature Rl and the second radius of curvature R2 are in the same direction. In an exemplary embodiment, the first radius of curvature Rl ranges from 25- 42 inches, and the second radius of curvature R2 ranges from 5-18 inches. The present invention also contemplates that the first radius of curvature and the second radius of curvature need not can be the same, assuming that the center of the radius of curvatures are different, or they can different.

[28] First beam 32 and second beam 34 can also be described in terms of their respective degrees of spread. The degree of spread is the angle from one end of the beam to the other measured from the center of the radius of curvature for that beam. For first beam 32, the degree of spread is indicated by angle θ in FIG. 3. The degree of spread for second beam 34 is indicated by angle λ. The present invention contemplates that the angle of spread can be the same for both beams, i.e., θ = λ, or the angles of spread for the beams can be different. In an exemplary embodiment, the angle of spread for each beam ranges from 8° to 55°. It can be appreciated that the angle of spread will be dictated by where the ends of the first beam and second beams are defined. Thus, smaller and greater angles are possible depending on where one considered the ends of the first beam and second to be.

[29] A first member 36 couples the first beam with the second beam. In addition, a second member 38 couples the first beam with the second beam. While two members 36 and 38 are shown in the illustrated embodiments coupling the first and second beams, it is to be understood that one member is sufficient to join these beams. Conversely, more than two such member can be provided. First member 36, second member 38, and any other such members can have any one of a variety of shapes, sizes, and configurations. First beam 32, second beam 34, first member 36, and second member 38, in this first exemplary embodiment are formed so that the overall structure is rigid or semi-rigid. For present purposes, "semi-rigid" means that these structures retain their shape when no load is applied on them, but flex to some degree to allow them to conform to the patient to reduce pressure points when a load is applied.

[30] In an exemplary embodiment of the present invention, first beam 32, second beam 34, first member 36, and second member 38 are formed as a unitary structure. More specifically, the present invention contemplates that the entire structure defined by first beam 32, second beam 34, first member 36, and second member 38 is formed from a fabric or cloth material, such as UBL (unbreakable loop backing), perforated neoprene (breathable rubber), a foam lamination with at least one side formed from UBL, or a Lycra laminated with a foam. A pad or cushion may be provided at one more locations, or over the entire structure, to provide a soft surface that contacts the user. Examples of suitable materials for such a pad or pads includes, foam, cloth, silicon, rubber, or any combination thereof.

[31] As shown in FIG. 4, the present invention contemplates providing reinforcements 40 at various locations on the headgear assembly. In the illustrated embodiment, reinforcements 40 are associated with first member 36 and second member 38 to assist in maintaining the spacing between first beam 32 and second beam 34. Reinforcements 40 can be provide using any conventional technique. For example, a rigid or semi-rigid support or batten can be provided in the fabric or material forming the portion of the headgear. To allow the amount of reinforcement or stiffening to be changed or removed pockets or other mechanisms for selectively attaching a reinforcement member to the headgear are contemplated. Reinforcing portions of the headgear assembly can also be accomplished by laminating or providing a stiffening agent, such as through screen printing process, on the portion of the headgear assembly where reinforcement is desired.

[32] As perhaps best shown in FIG. 2, when headgear assembly 30 is worn by a user, first beam 32 and second beam 34 bend or wrap around the head/neck of the user. Because the first and second beams have a radius of curvature Rl and R2, as described above, the structure defined by the first and second beams has a generally spherical shape, enabling the beams to conform more closely to the anatomy of the human head/neck. The allows the headgear assembly to fit the user in a firm, stable fashion that is also comfortable over a wide range of patient populations. [33] Coupling members 42a and 42b are attached to each end 44a and 44b of first beam 32. Similarly, coupling members 46a and 46b are attached to each end 48a and 48b of second beam 34. These coupling member are used to attach a patient interface device to the headgear assembly. In the illustrated embodiment, the coupling member extend from the ends of the first and second beams such that the coupling member on one side of the headgear assembly, e.g., coupling member 42a and 46a, are generally parallel to one another.

[34] In an exemplary embodiment, coupling members 42a, 42b, 46, and 46b are cloth or fabric so that they are flexible and lightweight and are attached to the ends of the first and second beams in any conventional manner. For example, the coupling member can be stitched, sewn, or sonic/heat welded onto the ends of the first and second beams. The present invention contemplates that coupling members 42a, 42b, 46, and 46b can have a variety of sizes, shapes, and configurations

[35] The present invention also contemplates that the attachment of the coupling members to the first and second beams can be fixed or adjustable, and can be selectively detachable. For example, coupling members 42a, 42b, 46, and 46b can be rotateably attached to first and second beams 32 and 32, the patient interface device, or both. In addition, the coupling members can be connected to the first and second beams, the interface device, or both via a snap or other detachable connectors so that the coupling member can be detached and reattached from the first and second beams or the interface device at the user's convenience.

[36] To attach the illustrated coupling members to a patient interface device the present invention contemplates threading a free end 50 of the coupling member through a slot or orifice provide in the patient interface or in a patient interface connector. The free end of the coupling member is then attached to the rest of the coupling member, as shown, for example, by arrow A in FIG. 4. Any conventional technique can be used to attached the free end of the coupling member to itself. For example, a hook and loop fastening method, such as VELCRO®, may be used. In which case, the free end of the coupling member includes one part of the hoop and loop fastener, and the other part of the hook and loop fastener is provided at one or more locations along the length of the coupling member. In a further exemplary embodiment, one or more of the coupling members, or portions thereof, are made from a stretchable fastening material, such as VELSTRETCH®, which is a spandex elastic band or strap.

[37] Referring now to FIGS. 5-7, a second embodiment of a headgear assembly

60 according to the principles of the present invention will be described. As in the previous embodiment, headgear assembly 60 includes first and second beams 62 and 64, respectively, and first and second coupling members 66 and 68. In this embodiment, however, first beam 62 includes end portions 70a and 70b separated by an elastic portion 72. End portions 70a, 70b, second beam 62, and first and second coupling members 66 and 68 are defined as a unitary structure that is semi-rigid, non-stretchy. Examples of materials suitable for forming this unitary structure include: spandex, a lycra lamination, a rubber band that includes a silicone strip, VELSTRETCH, or any combination thereof. As shown in FIG. 7, a pad 74 may be provided over the semi-rigid material to maximize patient comfort. Pad 74 can be provided over a majority of the structure, as shown, or it can be provided only at selected locations.

[38] The elastic portion of the first beam allows the top beam to adjust to fit the user in comfort. Any suitable elastic may be used for this portion of the headgear assembly. The present invention contemplates that the size, shape, elasticity, configuration, number, and locations of the elastic portions can be changed from that shown. For example, elastic portions can be provided in second beam 64, first member 66, second member 68, the coupling members, the junctions of any of these components, or any combination thereof.

[39] An example of a coupling member 80 and associated components suitable for use with any of the embodiments of the headgear assembly is shown in FIG. 8. In this embodiment, coupling member 80 is a strap attached for an end portion of the first or second beam. The strap is threaded through a slot 82 provided in a patient interface connector 84. In the illustrated embodiment, patient interface connector 84 is a ball-and- socket connector that attaches to a coupling provided on the patient interface device. A similar patient interface connector and patient interface device using such as connector is described in U.S. Patent No. 7,066,179, the contents of which are incorporated herein by reference.

[40] In this embodiment, a free end 86 is coupled to a clip 88, and coupling member 80 is also threaded through the clip. Moving clip 88 along the length of coupling member 80 changes the effective length of the coupling member, allowing the user to tighten or loosen the patient interface device on the user. To facilitate moving the clip a grip 90 is connected to one end of the clip.

[41] Various configurations for headgear assemblies 100, 110, 120, and 170 are shown in FIGS. 9-12, respectively. These alternative arrangements are provided to illustrate and emphasize that the headgear assembly of the present invention can have a variety of different configurations. The headgear assembly in each of these embodiments includes a first beam 102, 112, 122, and 172 having a first radius of curvature and a first angle of spread, and a second beam 104, 114, 124, and 174 having a second radius of curvature and a second angle of spread. FIG. 11 clearly illustrates that the first and second curvature need not be the same. In this embodiment, the first radius of curvature Rl is less than the second radius of curvature R2. In each embodiment, the first member and second member that couple the first beam to the second beam includes a reinforcing element or region 130.

[42] These headgear assemblies shown in FIGS. 9-12 also include coupling members 140a, 140b attached to the first beam and coupling members 142a, 142b coupled to the second beam. The coupling members on each side of the headgear assembly in FIGS. 9-11 extend away from the first and second beams at a non-zero angle α. Angle α is measured from the center of the coupling member. However, in the embodiment shown in FIG. 12, angle α between coupling members 140a and 140b is less than zero (-α). That is, the coupling members diverge toward one another, rather than extend away from one another. The present invention contemplates that angle α has a range of -10 ° to 20°. In the embodiment of FIG. 12, radius of curvature Rl for first beam 172 and radius of curvature R2 for second beam 174 originate from the same center centers.

[43] FIGS. 13 and 14 illustrate a sixth embodiment of a headgear assembly 150 according to the principles of the present invention. As in the previous embodiments, headgear assembly 150 includes first and second beams 152 and 154, respectively, and first and second members 156 and 158 span the first and second beams. Coupling members 162a, 162b are attached to end portions 160a, 160b of first beam 152, and coupling members 166, 166b are attached to end portions 164a, 164b of second beam 154. In this embodiment, coupling members 162a, 162b are rotateably attached to end portions

160a, 160b so that the coupling member can be moved, i.e., rotated, as indicated by arrows B to suit different types of patient interface devices. FIG. 14 also illustrates a first patient interface device 170 that is situated relatively low in the face of the user, and a second patient interface device 180 (shown in dashed lines) that is situation higher on the face. Giving the upper coupling members the ability to rotate allows the same headgear assembly to be used on a variety of different types of patient interface devices.

[44] In FIGS. 13 and 14, lower coupling members 166a and 166b are not rotateably coupled to the second beam. It is to be understood, however, that the present invention also contemplates rotateably attaching coupling members 166a and 166b to end portions 164a, 164b of second beam 154.

[45] Patient interface device 170, 180 couples a gas delivery conduit 190, typically referred to as a patient circuit, to an airway of the patient. Patient circuit 190 is typically a flexible tube that is coupled to the patient interface device. It should be noted that patient interface device suitable for use with the headgear assembly of the present invention can be any conventional patient interface device, including a nasal mask, oral mask, nasal/oral mask, full face mask, nasal cannula, chin mounted mask, or any other device that interfaces with an airway of a patient. As schematically illustrated in FIG. 14, patient circuit 190 communicates a flow of gas from a gas flow generating device 195, such as a conventional pressure support system or ventilator, so that gas is delivered from the gas flow generator to the airway of the patient.

[46] Gas flow generating device 195 can be any conventional device that accomplishes this function, such as a CPAP device, bi-level device, auto-titrating device, or any other pressure support system or ventilator using any conventional mode of therapy delivery. Although patient circuit 190 is illustrated in FIG. 14 as being a single limb circuit, the present invention contemplates that the patient circuit can include multiple limbs and can include other elements, such as filters, exhaust ports, flow control valve, pressure relief valves, humidifiers, and sensors.

[47] FIG. 15 illustrates yet another embodiment of a headgear assembly 180 according to the principles of the present invention. In this embodiment, the headgear assembly includes a cross strap 186 that spans the top of the user's head when the headgear assembly is donned by the user. One end 188a of cross strap 186 is attached to a first portion of first beam 182, and another end 188b of the cross straps is attached to a second portion of the first beam. Cross strap 186 is a flexible or semi-rigid member that is capable of flexing or molding to the shape of the top of the user's head.

[48] The present invention contemplates that the cross strap can be attached to the first beam in any conventional manner; in either a fixed (permanent) or separable manner. For example, end 188a can be permanently bonded to the first beam by being sewn, stitched, or welded. End 188b engages the second portion of first beam either directly, e.g., using a hook-and-loop engagement of the first beam to the cross strap, or indirectly, e.g., by looping the cross strap through an eyelet 190 provided on the first beam. In which case, the free end of the cross strap can be looped over the eyelet and attached back to the cross strap, as indicated by arrow C. This addition of cross strap 186 adds stability for lower mounting masks, such chin mount or small oral-nasal applications.

[49] It is to be understood that the number, type, size, function, and other characteristics of the objects that can be used as the patient interface device that are suitable for use with the headgear assembly of the present invention are nearly limitless. For example, the present invention contemplates that the headgear assembly of the present invention can be used to attach other medical devices to the patient, such as a spirometer or other monitor, to the patient. On the other hand, the headgear assembly can also be used to attach non-medical devices to the head of the user, such as gas masks, cosmetic objects, electronic devices, or apparel. No attempt is made in this disclosure to list the different types of objects that can serves as interface devices that can be held on the head of the patient by the headgear assembly of the present invention.

[50] Although the invention has been described in detail for the purpose of illustration based on what is currently considered to be the most practical and preferred embodiments, it is to be understood that such detail is solely for that purpose and that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover modifications and equivalent arrangements that are within the spirit and scope of the appended claims. For example, it is to be understood that, to the extent possible, the present invention contemplates that one or more features of any embodiment of the present invention can be combined with the features of any other embodiment.

Claims

What is claimed is:

1. A headgear assembly (30, 150, 180) for attaching an object to a head of a user comprising: a first beam adapted (32, 152, 182) to wrap around a back of a user's neck or a back of a user's head, wherein the first beam is generally planer and is adapted to be disposed in a first plane responsive to being stretched flat, and wherein the first beam has a first radius of curvature defined in the first plane; a second beam (34, 154, 184) adapted to wrap around a back of a user's neck or a back of a user's head, wherein the second beam is generally planer and is adapted to be disposed in the first plane responsive to being stretched flat, and wherein the second beam has a second radius of curvature defined in the first plane in a same direction as the first radius of curvature; and a first member (36, 38) coupling the first beam with the second beam.

2. The headgear assembly of claim 1, wherein (a) the first radius of curvature and the second radius of curvature are substantially the same, or (b) the first radius of curvature is greater than the second radius of curvature.

3. The headgear assembly of claim 1 , wherein the first beam has a first length, the second beam has a second length, and wherein (a) the first length is substantially the same as the second length, or (b) the first length is greater than the second length.

4. The headgear assembly of claim 1 , further comprising a second member coupling the first beam with the second beam.

5. The headgear assembly of claim 1, wherein the first beam, the second beam, and the first member are defined as a unitary structure.

6. The headgear assembly of claim 1, further comprising a reinforcing member (130) adapted to be selectively coupled to the first beam, the second beam, the first member, or any combination thereof.

7. The headgear assembly of claim 1, wherein at least a portion of the first beam, the second beam, the first member is defined by an expandable material or a semirigid material.

8. The headgear assembly of claim 1 , wherein the first member is also disposed in the first plane responsive to being stretched flat.

9. The headgear assembly of claim 1, further comprising: a first coupling member (42a, 42b) attached to a first end of the first beam; and a second coupling member (46a, 46b) attached to a first end of the second beam, wherein the first and the second coupling portions are linear, wherein the first end of the first beam and the second end of the second beam are disposed in one side of the headgear assembly, and wherein the first and the second beams are configured such that the first and the second coupling members are not parallel to one another responsive to the headgear assembly being stretched flat.

10. The headgear assembly of claim 1, wherein a centerline separates a first half of the headgear assembly from a second half of the headgear assembly, and wherein the first beam, the second beam, or both are symmetrical about the centerline.

1 1. The headgear assembly of claim 1 , further comprising coupling members attached to an end of the first beam, the second beam, or both, wherein the coupling members are generally strait (42a, 42b, 46a, 46b).

12. The headgear assembly of claim 11, further comprising an adjusting mechanism (88) associated with the coupling members adapted to adjust a length of the coupling members.

13. The headgear assembly of claim 11 , wherein the coupling members are rotateably attached to the ends of the first beam, the second beam, or both.

14. The headgear assembly of claim 11, further comprising a patient interface connector (84) operatively coupled to each coupling member.

15. The headgear assembly of claim 14, wherein the patient interface connector is movable along a length of the coupling member to which the patient interface connector is coupled.

16. The headgear assembly of claim 11, wherein at least a portion of at least one of the coupling members is defined by an expandable material.

17. The headgear assembly of claim 16, wherein the expandable material is an elasticized fastening material.

18. The headgear assembly of claim 1, further comprising a cross strap spanning between two portions of the first beam.