Forehead supports for facial masks

1. A mask assembly, comprising:

a mask frame having a frame connector extending from the mask frame;

a forehead cushion support comprising a tube and a forehead cushion support plate, the forehead cushion support plate extending from the tube; and

an adjustment knob movably mounted to the frame connector,

wherein the tube is movably mounted to the frame connector such that the forehead cushion support is movable with respect to the mask frame,

wherein the forehead cushion support is movable with respect to the mask frame along an axis,

wherein the adjustment knob is rotatable about the axis, and

further wherein the tube includes at least one split that allows the exterior of the tube to be deflected and narrowed when inserting the tube into the frame connector.

2. The mask assembly of claim 1 , wherein the at least one split extends along substantially the entire length of the tube from an end opposite said forehead cushion support plate to said forehead cushion support plate.

3. The mask assembly of claim 1 , wherein the at least one split extends along a horizontal plane containing a longitudinal axis of the tube.

4. The mask assembly of claim 1 , wherein the at least one split extends along a vertical plane containing a longitudinal axis of the tube.

5. The mask assembly of claim 1 , wherein the frame connector is structured to receive the tube and to define a linear path of movement of the forehead cushion support.

6. The mask assembly of claim 5 , wherein a ridge is provided at an end of the tube opposite the forehead cushion support plate to prevent inadvertent disassembly of the frame connector and the forehead cushion support by engagement between the frame connector and the ridge in an extended position of the forehead cushion support.

7. The mask assembly of claim 1 , wherein the adjustment knob includes a threaded shaft.

8. The mask assembly of claim 7 , wherein the tube includes an internal thread shaped and dimensioned to mesh with the threaded shaft.

9. The mask assembly of claim 1 , wherein the forehead cushion support plate is angled about 15-25° from vertical with respect to a longitudinal axis of the tube.

10. The mask assembly of claim 1 , wherein a slot is provided in the forehead cushion support plate to allow a headgear strap to be fitted therein.

11. The mask assembly of claim 1 , wherein the adjustment knob is structured to be attached to the frame connector with a snap-fit.

12. The mask assembly of claim 11 , wherein the frame connector comprises at least one retention feature structured to engage a corresponding annular rim of a segment of the adjustment knob.

13. The mask assembly of claim 12 , wherein the frame connector comprises at least two retention features.

14. The mask assembly of claim 1 , wherein the adjustment knob includes a retention arm structured to engage a ridge on the frame connector to allow for incremental adjustment of the forehead cushion support.

15. The mask assembly of claim 1 , wherein the tube is structured such that the forehead cushion support moves linearly relative to the frame connector when the tube is movably mounted to the frame connector.

16. The mask assembly of claim 1 , further comprising a cushion removably attached to the mask frame.

17. The mask assembly of claim 1 , further comprising a cushion removably attached to the mask frame, and

wherein the adjustment knob includes a threaded shaft.

18. A mask assembly for supplying breathable gas to a patient, comprising:

a mask frame having a frame connector extending from the mask frame;

a forehead cushion support comprising a tube and a forehead cushion support plate, the forehead cushion support plate extending from the tube; and

an adjustment knob movably mounted to the frame connector,

wherein the tube is movably mounted to the frame connector such that the forehead cushion support is movable with respect to said frame connector,

wherein the forehead cushion support is movable with respect to the mask frame along an axis,

wherein the adjustment knob is rotatable about the axis, and

further wherein the tube is configured to be deflected and narrowed to allow insertion of the tube into the frame connector.

19. The mask assembly of claim 18 , wherein the tube is configured to be deflected and narrowed along substantially the entire length of the tube from an end of the tube opposite said forehead cushion support plate to said forehead cushion support plate.

20. The mask assembly of claim 18 , wherein the tube is configured to be deflected and narrowed along a horizontal plane containing a longitudinal axis of the tube.

21. The mask assembly of claim 18 , wherein the tube is configured to be deflected and narrowed along a vertical plane containing a longitudinal axis of the tube.

22. The mask assembly of claim 18 , wherein the tube is structured such that the forehead cushion support moves linearly relative to the frame connector when the tube is movably mounted to the frame connector.

23. The mask assembly of claim 18 , further comprising a cushion removably attached to the mask frame.

24. The mask assembly of claim 18 , further comprising a cushion removably attached to the mask frame, and

wherein the adjustment knob includes a threaded shaft.