Cushion for a respiratory mask assembly

1. A respiratory mask assembly, comprising:

a frame; and

a cushion provided to the frame, the cushion including:

a non-face contacting portion removably attached to the frame;

a face-contacting portion adapted to engage a patient's face, the face-contacting portion including a side wall, a rim extending from the side wall and curving inwardly into a cavity of the cushion, and a membrane substantially surrounding the rim and including an inside surface spaced from an outside surface of the rim;

a gusset portion extending radially outwardly from the side wall of the face-contacting portion; and

a reinforcing ring between the gusset portion and the face-contacting portion, said reinforcing ring being constructed and arranged to act as a stiffening hoop to reduce the tendency of the cushion to expand when under pressure.

2. A respiratory mask assembly according to claim 1 , wherein said reinforcing ring comprises polycarbonate.

3. A respiratory mask assembly according to claim 1 , wherein the respiratory mask assembly is a nasal mask assembly.

4. A respiratory mask assembly according to claim 1 , further comprising a forehead support provided to an upper portion of the frame.

5. A respiratory mask assembly according to claim 4 , further comprising headgear including upper straps removably connected to clip structures provided to the forehead support and lower straps removably connected to clip structures provided to the frame.

6. A respiratory mask assembly according to claim 1 , further comprising a swivel elbow assembly provided to a front portion of the frame.

7. A respiratory mask assembly according to claim 1 , wherein the membrane is thinner than the rim.

8. A respiratory mask assembly according to claim 1 , wherein the gusset portion extends radially outwardly a distance away from the side wall of the face-contacting portion to provide additional footprint area outside a contact line of the cushion.

9. A respiratory mask assembly according to claim 8 , wherein the distance is varied in different regions of the gusset portion.

10. A respiratory mask assembly according to claim 9 , wherein the distance in a nasal bridge region is different than the distance in cheek regions.

11. A respiratory mask assembly according to claim 9 , wherein the additional footprint area is at least partially determinative of a contact force applied to the patient's face through the face-contacting portion, and the distance is varied in different regions of the gusset portion to vary the contact force applied in different regions of the patient's face.

12. A respiratory mask assembly according to claim 1 , wherein the gusset portion extends around an entire perimeter of the cushion.

13. A respiratory mask assembly according to claim 1 , further comprising a spring structure to provide a component of a contact force on the patient's face.

14. A respiratory mask assembly according to claim 1 , wherein the non-face contacting portion, the face-contacting portion, and the gusset portion have a generally triangular shape.

15. A respiratory mask assembly according to claim 1 , further comprising a cushion clip detachably engaged with the frame such that a shoulder of the non-face contacting portion is positioned between the clip and the frame to attach the cushion to the frame.

16. A respiratory mask assembly according to claim 1 , wherein the non-face contacting portion, the face-contacting portion, and the gusset portion comprise silicone.

17. A respiratory mask assembly according to claim 1 , wherein the respiratory mask assembly is a nasal and mouth mask assembly.

18. A respiratory mask assembly according to claim 1 , wherein the reinforcing ring is provided to the cushion at a point between the gusset portion and the face-contacting portion, the reinforcing ring constructed and arranged to reduce the tendency of the cushion to expand at the point when under pressure.

19. A respiratory mask assembly according to claim 18 , wherein the reinforcing ring extends in a ring around the entire perimeter of the cushion with the point provided at a junction between the gusset portion and the side wall of the face-contacting portion.

20. A respiratory mask assembly according to claim 1 , wherein at least a portion of the reinforcing ring extends along an interior surface of the cushion within the cavity.

21. A respiratory mask assembly according to claim 1 , wherein the reinforcing ring comprises an overmolded connection to the cushion.

22. A respiratory mask assembly according to claim 21 , wherein at least a portion of the reinforcing ring extends along an interior surface of the cushion within a cavity of the cushion.

23. A respiratory mask assembly according to claim 21 , wherein the reinforcing ring comprises polycarbonate.

24. A respiratory mask assembly according to claim 21 , wherein the reinforcing ring comprises the overmolded connection to the cushion at a point between the gusset portion and the face-contacting portion such that the reinforcing ring extends in a ring around the entire perimeter of the cushion with the point provided at a junction between the gusset portion and the side wall of the face-contacting portion.

25. A respiratory mask assembly according to claim 1 , wherein the reinforcing ring comprises a push-fit connection to the cushion.

26. A respiratory mask assembly according to claim 25 , wherein at least a portion of the reinforcing ring extends along an interior surface of the cushion within a cavity of the cushion.

27. A respiratory mask assembly according to claim 25 , wherein the reinforcing ring comprises polycarbonate.

28. A respiratory mask assembly according to claim 25 , wherein the reinforcing ring comprises the push-fit connection to the cushion at a point between the gusset portion and the face-contacting portion such that the reinforcing ring extends in a ring around the entire perimeter of the cushion with the point provided at a junction between the gusset portion and the side wall of the face-contacting portion.