Chair back mechanism and control assembly
A chair assembly includes a seat support structure, a back support structure, a back tensioning assembly adjustable between low and high tension positions, an actuator assembly adapted to adjust the back tensioning assembly between the low and high tension positions, a control input assembly actuable by rotating the portion of the control input assembly, and a control link assembly operably coupling the control input assembly with the actuator assembly to adjust the back tensioning assembly between the low and high tension positions upon rotation of the portion of the control assembly by a seated user, wherein a number of rotations of the portion of the control input assembly is not limited by the control link.
1. A chair assembly, comprising:
a seat support structure;
a back support structure movable between an upright position and a reclined position;
a back tensioning assembly that biases the back assembly from the reclined position towards the upright position, wherein the back tension assembly is adjustable between a low tension position, wherein the back tensioning assembly applies a first biasing force to the back assembly, and a high tension position, wherein the back tensioning assembly applies a second biasing force to the back assembly, and wherein the second biasing force is substantially greater than the first biasing force;
an actuator assembly operably coupled to the back tensioning assembly and adapted to adjust the back tensioning assembly between the low and high tension positions;
a control input assembly operably coupled to the seat support structure, wherein at least a portion of the control input assembly may be actuated by a seated user by rotating the portion of the control input assembly; and
a control link assembly operably coupling the control input assembly with the actuator assembly to adjust the back tensioning assembly between the low and high tension positions upon rotation of the portion of the control assembly by a seated user, wherein a number of rotations of the portion of the control input assembly is not limited by the control link.
2. The chair assembly of claim 1 , wherein the control link assembly comprises:
a first shaft having a first end and a second end;
a first universal joint assembly coupling the first end of the first shaft to the control input assembly;
a second shaft have a first end and second end;
a second universal joint assembly and a third universal joint assembly each coupling the second end of the first shaft with the first end of the second shaft; and
a fourth universal joint assembly coupling the second end of the second shaft with the actuator assembly.
3. The chair assembly of claim 2 , wherein at least a select one of the first universal joint assembly, the second universal joint assembly, the third universal joint assembly and the fourth universal joint assembly includes a ball and a socket receiving the ball.
4. The chair assembly of claim 2 , wherein the first shaft is rotatable about a first axis, and wherein the second shaft is rotatable about a second axis that is substantially orthogonal to the first axis.
5. The chair assembly of claim 4 , wherein the back tensioning assembly includes a portion moveable in a first direction between a first position and a second position, and movement of the portion of the back tensioning assembly between the first and second positions adjusts the back tensioning assembly between the low and high tension positions, and wherein the first direction is substantially orthogonal to the second axis.
6. The chair assembly of claim 1 , wherein the back tensioning assembly includes a spring member extendable between a first length at which the spring member exerts the first biasing force on the back assembly, and a second length at which the spring member exerts the second biasing force on the back assembly.
7. The chair assembly of claim 6 , wherein the first length is less than the second length.
8. The chair assembly of claim 1 , wherein the portion of the back tensioning assembly includes a threaded member.
9. The chair assembly of claim 1 , further comprising:
a first beveled gear assembly operably coupling the second end of the first control link to the first end of the second control link.
10. The chair assembly of claim 9 , further comprising:
a second beveled gear assembly operably coupling the second end of the second control link to the actuator assembly.
11. The chair assembly of claim 1 , further comprising:
a spline assembly operably coupling the second shaft to the actuator assembly, thereby allowing expansion of a distance between the first end of the second shaft and the actuator assembly.
12. A chair assembly, comprising:
a first chair structure;
a second chair structure movable relative to the first chair structure between a first position and a second position;
an actuator assembly operably coupled to the second chair structure and adapted to move the second chair structure between the first and second positions;
a control input assembly operably coupled to the first chair structure, wherein at least a portion of the control input assembly may be actuated by a seated user;
a control link assembly operably coupling the control input assembly with the actuator assembly to move the second control chair structure between the first and second positions upon an input by a seated user to the control input assembly; and
a damper structure operably coupled to at least a select one of the actuator assembly, the control assembly and the control link assembly, wherein the damper structure damps a relative movement between at least a select two of the actuator assembly, the control input assembly and the control link assembly.
13. The chair assembly of claim 12 , wherein the damper structure is located between the control input assembly and the control link assembly.
14. The chair assembly of claim 13 , wherein the damper structure damps the relative rotational movement between the control input assembly and the control link assembly.
15. The chair assembly of claim 14 , wherein the control link assembly comprises a shaft, and wherein the damper structure is positioned about an end of the shaft.
16. The chair assembly of claim 15 , wherein the control input assembly includes a housing, and wherein the damper structure abuts a portion of the housing.
17. The chair assembly of claim 16 , wherein the housing defines an interior space, and wherein the damper structure is at least partially located within the interior space of the housing.
18. The chair assembly of claim 15 , wherein the end of the shaft includes a portion of a universal joint assembly.
19. The chair assembly of claim 18 , wherein the universal joint assembly includes a ball and a socket receiving the ball.
20. The chair assembly of claim 12 , wherein the control input assembly includes a housing defining an interior space, and wherein the damper structure is at least partially located within the interior space of the housing.
21. The chair assembly of claim 20 , wherein the damper structure damps the relative rotational movement between at least a portion of the control input assembly and the control link assembly.
22. The chair assembly of claim 12 , wherein the damper structure damps the relative rotational movement between the portion of the control input assembly and the control link assembly.