Headrest structure, headrest cushion and passenger seat

1. A headrest structure for a passenger seat, the headrest structure comprising:

an adjustable headrest frame for connection to a passenger seat; and

a headrest cushion mounted to the adjustable headrest frame such that the headrest cushion is moveable relative to a seat back of the passenger seat by way of the adjustable headrest frame;

wherein the headrest cushion comprises cutouts formed in the support surface, the cutouts being aligned with respective folding joints of the adjustable headrest frame for folding side portions of the headrest frames relative to a mid-portion of the headrest frame;

wherein the adjustable headrest frame is configured for providing forward and backward tilt such that a top of the adjustable headrest frame and a bottom of the adjustable headrest frame move in different horizontal directions relative to their respective positions in an upright orientation of the adjustable headrest frame, and

wherein the headrest frame comprises a hinge element connected with a first end thereof at a fixed location on the headrest frame and with a second end thereof to a mounting brace for connection of the headrest frame to the passenger seat in an upward and downward moveable manner.

2. The headrest structure as claimed in claim 1 , wherein the headrest cushion comprises a mid-portion made from a softer material compared to side portions of the headrest cushion.

3. The headrest structure as claimed in claim 2 , wherein the mid-portion of the headrest cushion is mounted to a center mounting plate of the adjustable headrest frame.

4. The headrest structure as claimed in claim 2 , wherein the side portions of the headrest cushion are mounted to respective side mounting plates of the adjustable headrest frame.

5. The headrest structure as claimed in claim 1 , wherein the support surface includes a concave upper part and a convex bottom part, and wherein the concave upper part of the support surface directly meets the convex bottom part of the support surface such that a cross-section of the headrest cushion along a vertical axis relative to the passenger seat is substantially reverse S-shaped.

6. The headrest structure as claimed in claim 5 , wherein the curvature of the concave upper part is shallower than the curvature of the convex lower part.

7. The headrest structure as claimed in claim 5 , wherein the concave upper part and the convex bottom part each extend substantially across the horizontal width of the headrest cushion relative to the passenger seat.

8. The headrest structure as claimed in claim 1 , wherein the adjustable headrest frame comprises a 4-way headrest frame for allowing upward and downward movements, as well as folding to provide sideway head support.

9. The headrest structure as claimed in claim 1 , wherein the adjustable headrest frame comprises a 6-way headrest frame for allowing upward and downward movements, folding to provide sideway head support and forward and backward tilt.

10. The headrest structure as claimed in claim 9 , wherein the headrest frame is configured such that the headrest cushion is moveable in upward and downward directions, in forward and backward tilt, and folding along two fold lines.

11. A passenger seat comprising a headrest structure as claimed in claim 1 .

12. The headrest structure of claim 1 , wherein the adjustable headrest frame is configured for providing forward and backward tilt such that an axis of rotation for the forward and backward tilt is disposed at about 1/4 of the height of the adjustable headrest frame below the top of the adjustable headrest frame.

13. The headrest structure of claim 1 , wherein the adjustable headrest frame is configured for providing forward and backward tilt such that a distance of movement in a forward direction of the bottom of the adjustable headrest frame is larger than a distance of movement in a backward direction of the top of the adjustable headrest frame during backward tilting from the upright orientation of the adjustable headrest frame.