Elbow for mask assembly

1. An elbow assembly for a respiratory mask comprising an elbow, wherein the elbow comprises:

a) a first end portion comprising a surface adapted to engage a surface of a gas delivery tube; and

b) a second end portion provided to the mask,

wherein the elbow further defines:

i) an inlet port to deliver incoming gas in a first direction to a nasal breathing cavity defined by the mask, and

ii) an exhaust port separated from the inlet port by at least one baffle,

wherein the baffle directs the incoming gas to turn into the nasal breathing cavity, and the baffle is configured to direct exhaust gas away from the nasal breathing cavity in a substantially linear direction through the exhaust port into a vent cavity to be expelled to atmosphere through a wall of the elbow adjacent the exhaust port, and

wherein the baffle extends beyond the second end portion.

2. The elbow assembly according to claim 1 , wherein the at least one baffle includes a first and a second baffle situated across from one another.

3. The elbow assembly according to claim 1 , wherein the baffle is oriented in the elbow about a center line passing from a top of the elbow to a bottom of the elbow such that a bottom of the baffle is aligned with the bottom of the elbow.

4. The elbow assembly according to claim 1 , wherein the exhaust port is completely surrounded by the inlet port.

5. The elbow assembly according to claim 1 , wherein the baffle is substantially circular.

6. The elbow assembly according to claim 1 , wherein the baffle is oriented in the elbow about a center line passing from a right side of the elbow to a left side of the elbow.

7. The elbow assembly according to claim 1 , wherein the baffle further comprises a protrusion adapted to protrude into a breathing cavity of the mask.

8. The elbow assembly according to claim 1 , wherein the second end portion of the elbow further comprises:

iii) a resilient collar that substantially surrounds a mating portion to define a receiving space between the collar and the mating portion, and wherein the collar is configured to flex outwardly upon entry of a flange, formed on the mask, into the receiving space until the second end portion reaches an operative position in which the collar flexes inwardly by virtue of the resiliency thereof so as to lock the flange with respect to the collar and thereby detachably couple the elbow to the mask.

9. The elbow assembly according to claim 8 , wherein the mating portion extends beyond the collar to facilitate alignment of the second end portion of the elbow with respect to the mask.

10. The elbow assembly according to claim 8 , wherein the elbow further comprises release portions on each side of the collar that are flexed towards one another to move the collar outwardly so as to allow the flange to move out of the receiving space to detach the elbow from the mask.

11. The elbow assembly according to claim 1 , further comprising:

c) a removable vent cover detachably connected to the elbow, wherein the vent cover includes a main body and at least one vent aperture for gas washout.

12. The elbow assembly according to claim 11 , wherein the vent cover is made of a resilient material.

13. The elbow assembly according to claim 1 , wherein the at least one baffle is M-shaped, V-shaped or C-shaped.

14. The elbow assembly according to claim 1 , wherein the exhaust port increases in area along the second direction.

15. A respiratory mask assembly comprising:

a) a mask frame further comprising at least one aperture;

b) a cushion, and

c) an elbow assembly according to claim 1 .

16. The mask assembly according to claim 15 , wherein the aperture has a diameter between about 20 mm to about 40 mm.

17. The mask assembly according to claim 15 , wherein the aperture has a generally circular shape.

18. The mask assembly according to claim 15 , wherein the aperture further comprises a ring.

19. The mask assembly according to claim 18 , wherein the ring further comprises an inner ring.

20. The mask assembly according to claim 19 , wherein the inner ring is linked to an inner diameter of the aperture by at least one connector.

21. The mask assembly according to claim 20 , wherein the at least one connector comprises at least one notch adapted to engage the elbow.

22. The mask assembly according to claim 19 , wherein the ring further comprises an outer ring surrounding the inner ring.

23. The mask assembly according to claim 22 , wherein the outer ring has a diameter between about 20 mm to about 40 mm.

24. The mask assembly according to claim 19 , wherein the inner ring defines a cavity.

25. The mask assembly according to claim 24 , wherein the cavity has a diameter between about 4 mm to about 12 mm.

26. The mask assembly according to claim 25 , wherein the cavity has a diameter between about 6 mm to about 10 mm.