Seat pan cam follower with drop down mechanism

1. A chair comprising:

a seat frame having a front end and a rear end;

a seat back attached to the rear end of the seat frame, said seat back being movable between a generally upright and a generally reclined position;

a seat articulator including a ramp bar, the ramp bar having a first end connected to the seat back and a second end proximal to the front end of the seat frame, the ramp bar including an upper edge and a front edge distal to the seat back, said front edge terminating in a first catch portion immovably associated with the ramp bar displaced downward from the upper edge and extending forward from the front edge, and a lower edge in contact with a cross member located between a first and a second side of the seat frame;

a seat pan pivotally connected to the seat frame;

a drop down link pivotally attached to the seat pan; and

a cam roller attached to the drop down link, the cam roller positioned in contact with the ramp bar.

2. The chair of claim 1 , wherein an activation lever is connected to the drop down link.

3. The chair of claim 1 , wherein:

said front edge is located at approximately a 90° angle with respect to the upper edge; and

said first catch portion extends forward from the front edge at approximately 90° with respect to the front edge.

4. The chair of claim 1 , wherein:

the seat back is in a generally upright position;

the cam roller is on the upper edge of the ramp bar adjacent the front edge; and

the seat pan is angled approximately 6° with respect to the seat frame.

5. The chair of claim 4 , wherein the drop down link forms approximately 45° angle with the upper edge.

6. The chair of claim 1 , wherein:

the seat back is in a generally upright position;

the cam roller is in contact with the first catch portion; and

the seat pan is aligned at approximately 0° with the seat frame.

7. The chair of claim 6 , wherein the drop down link forms approximately a 90° angle with respect to the seat pan.

8. The chair of claim 1 , wherein the drop down link is spring biased at approximately a 45° angle with respect to the seat pan.

9. The chair of claim 1 , wherein:

the seat back is inclined approximately 45° with respect to the seat frame;

the cam roller is positioned on the upper edge of the ramp bar; and

the ramp bar extends forward such that a second catch portion formed by a bottom edge of the ramp bar is in contact with the cross member, thereby causing the seat pan to be elevated approximately 10° with respect to the seat frame.

10. The chair of claim 1 , wherein:

the seat back is fully reclined;

the cam roller is positioned in an upper catch portion distal to the front edge; and

the ramp bar extends forward such that the bottom edge of the ramp bar extends forward of the cross member, thereby causing the seat pan to be aligned at approximately 0° with respect to the seat pan.

11. The chair of claim 1 , wherein the drop down link includes:

a first end connected to the seat pan;

a second end proximal to the ramp bar;

a cam follower connected to the drop-down link; and

a drop-down lever attached to the drop-down link.

12. The chair of claim 11 , wherein:

the cam follower is connected to an inboard side of the drop-down link; and

the drop-down lever is attached to an outboard side of the drop-down link.

13. The chair of claim 11 , wherein the second end of the drop-down link is adjacent the first catch portion of the ramp bar when the seat pan is aligned with the seat frame.

14. The chair of claim 11 , wherein the second end of the drop-down link is adjacent the upper edge of the ramp bar when the seat pan is angled approximately 2-6° with respect to the seat frame.

15. The chair of claim 1 , wherein

a second ramp bar is located on a second side of the seat pan opposite the first ramp bar; a second drop-down link is pivotally attached to the second side of the seat pan; and

a cross-tube translates rotation between the first drop-down link and the second drop-down link.

16. The chair of claim 1 , wherein the first catch portion is formed as an integral part of the ramp bar.

17. A chair comprising:

a seat frame having a front end and a rear end;

a seat back attached to the rear end of the seat frame, said seat back being movable between a generally upright and a generally reclined position;

a seat articulator including a ramp bar, the ramp bar having a first end connected to the seat back and a second end proximal to the front end of the seat frame, the ramp bar including an upper edge that forms a front edge distal to the seat back, said front edge terminating in a first catch portion displaced downward from the upper edge and extending forward from the front edge, and a lower edge in contact with a cross member located between a first and a second side of the seat frame;

a drop down link pivotally attached to a seat pan;

a cam roller attached to the drop down link, the cam roller positioned in contact with the ramp bar; and

the seat pan is pivotally connected to the seat frame and has an angle with respect to the seat frame that decreases when the cam roller is moved from the upper edge to the first catch portion.

18. A chair comprising:

a seat frame having a front end and a rear end;

a seat back attached to the rear end of the seat frame, said seat back being movable between a generally upright and a generally reclined position;

a seat articulator including a ramp bar, the ramp bar having a first end connected to the seat back and a second end proximal to the front end of the seat frame, the ramp bar including an upper edge that forms a front edge distal to the seat back, said front edge terminating in a first catch portion displaced downward from the upper edge and extending forward from the front edge, and a lower edge in contact with a cross member located between a first and a second side of the seat frame;

a seat pan pivotally connected to the seat frame;

a drop down link located closer to the front end than the rear end and is pivotally attached to the seat pan; and

a cam roller attached to the drop down link, the cam roller positioned in contact with the ramp bar.