Control assembly for chair

• US 9,049,935 B2
• Filed: 09/17/2013
• Issued: 06/09/2015
• Est. Priority Date: 09/20/2012
• Status: Active Grant

• Current Assignee: Steelcase Incorporated
• Original Assignee: Steelcase Incorporated
• Inventors: Karsten, Gary Lee, Heidmann, Kurt R., Andres, Todd T., Battey, Robert J.
• Primary Examiner(s): WHITE, RODNEY BARNETT
• Application Number:
  US14/029,224
• Publication Number:
  US 20140077552A1
• Time in Patent Office: 630 Days
• Field of Search: 297/285, 297/296
• US Class Current: 1/1
• CPC Class Codes: A47C 1/024 the parts, being the back-rest, or the back-rest and seat unit, having adjustable and lockable inclination
• CPC Class Codes: A47C 1/03 the parts being arm-rests conversion into a bed A47C17/12
• CPC Class Codes: A47C 1/0307 adjustable rectilinearly in horizontal direction
• CPC Class Codes: A47C 1/0308 adjustable by rotation
• CPC Class Codes: A47C 1/032 the parts being movably-coupled seat and back-rest A47C1/035 takes precedence
• CPC Class Codes: A47C 1/03255 with a central column, e.g. rocking office chairs
• CPC Class Codes: A47C 1/03261 characterised by elastic means
• CPC Class Codes: A47C 1/03266 with adjustable elasticity
• CPC Class Codes: A47C 1/03272 with coil springs
• CPC Class Codes: A47C 1/03274 of torsion type
• CPC Class Codes: A47C 1/14 Beach chairs ; Chairs for outdoor use, e.g. chairs for relaxation or sun-tanning
• CPC Class Codes: A47C 3/20 Chairs or stools with vertically-adjustable seats tables with variable height A47B9/00
• CPC Class Codes: A47C 3/30 with vertically-acting fluid cylinder
• CPC Class Codes: A47C 31/02 Upholstery attaching means quilting, quilting means, fastening, fixing or finishing upholstery B68G7/00
• CPC Class Codes: A47C 31/023 connecting upholstery to frames, e.g. by hooks, clips, snap fasteners, clamping means or the like
• CPC Class Codes: A47C 5/00 Chairs of special materials
• CPC Class Codes: A47C 5/12 of plastics, with or without reinforcement
• CPC Class Codes: A47C 7/004 for chairs or stools with central column, e.g. office chairs
• CPC Class Codes: A47C 7/006 with castors
• CPC Class Codes: A47C 7/029 of non-adjustable shape adapted to a user contour or ergonomic seating positions
• CPC Class Codes: A47C 7/14 : of adjustable shape; elastically mounted ; adaptable to a user contour or ergonomic seating positions movably-coupled seat and backrests with elastic adjustment means A47C1/03261; elastically-mounted back-rests or backrest-seat units in the base frame A47C7/44
• CPC Class Codes: A47C 7/185 : with a stiff, rigid support
• CPC Class Codes: A47C 7/24 : Upholstered seats A47C7/18 takes precedence
• CPC Class Codes: A47C 7/40 : for the back
• CPC Class Codes: A47C 7/44 : with elastically-mounted back-rest or backrest-seat unit in the base frame
• CPC Class Codes: A47C 7/441 : with adjustable elasticity
• CPC Class Codes: A47C 7/443 : with coil springs
• CPC Class Codes: A47C 7/46 : with special, e.g. adjustable , lumbar region support profile; "Ackerblom" profile chairs
• CPC Class Codes: A47C 7/462 : adjustable by mechanical means
• CPC Class Codes: A47C 7/54 : Supports for the arms
• CPC Class Codes: B68G 7/12 : Other elements specially adapted for fastening, fixing, or finishing, in upholstery work
• CPC Class Codes: Y10T 29/481 : Method
• CPC Class Codes: Y10T 29/49826 : Assembling or joining
• CPC Class Codes: Y10T 29/49947 : by applying separate fastener

Abstract

A control assembly for a chair including a base structure including a first pivot point and a second pivot point spaced from the first pivot point, and a seat support structure directly pivotably coupled to the base structure for rotation about the first pivot point, a back support structure pivotably coupled to the base structure for rotation about the second pivot point, wherein the back support structure is adapted to move between a first and second position, a control link having a first end operably coupled to the seat support structure, and a second end operably coupled to the back support structure, and a biasing assembly exerting a biasing torque about the second pivot point that biases the back support structure from the second position toward the first position, wherein the biasing torque is adjustable between first and second magnitudes when the back support structure is in the first position.

Claims

1. A control assembly for a chair, comprising:

a base structure including a stationary first pivot point and a stationary second pivot point spaced from the stationary first pivot point, wherein the base structure is adapted to be attached to a ground-abutting base support structure;

a seat support structure directly pivotably coupled to the base structure for rotation about the stationary first pivot point, wherein the seat support structure is adapted to support a seated user thereon;

a back support structure directly pivotably coupled to the base structure for rotation about the stationary second pivot point, wherein the back support structure is adapted to move between a first position and a second position;

a control link having a first end operably coupled to the seat support structure, and a second end operably coupled to the back support structure; and

at least one biasing assembly exerting a biasing torque about the stationary second pivot point and exerting a biasing force on the back support structure that biases the back support structure from the second position towards the first position, wherein the biasing torque is adjustable between first and second magnitudes when the back support structure is in the first position, and wherein the second magnitude is greater than the first magnitude.

2. The control assembly of claim 1, wherein the biasing force is adjustable between a first magnitude and a second magnitude when the back support structure is in the first position, and wherein the second magnitude of the biasing force is greater than the first magnitude of the biasing force.

3. The control assembly of claim 1, further comprising:

an adjustment assembly operably coupled to the at least one biasing assembly to adjust the biasing torque between the first and second magnitudes, wherein the adjustment assembly adjusts the at least one biasing assembly between a first configuration corresponding to the first magnitude of the biasing force and a second configuration corresponding to the second magnitude of the biasing force.

4. The control assembly of claim 3, wherein the adjustment assembly includes a movable input member that changes the magnitude of the biasing torque upon movement of the movable input member between a first position and a second position.

5. The control assembly of claim 3, wherein the biasing torque is generated by a resilient biasing member that shifts between a first shape corresponding to the first magnitude of the biasing torque and a second shape corresponding to the second magnitude of the biasing torque.

6. The control assembly of claim 5, wherein the resilient biasing member comprises a spring member having a first end, a second end and a length defined between the first end and the second end, and wherein a change in the length of the spring member changes the magnitude of the biasing torque between the first and second magnitudes.

7. The control assembly of claim 6, wherein the first end of the spring member is operably coupled to at least a select one of the base structure, the seat support structure, the back support structure and the control link, and wherein a change of a position of the second end of the spring member relative to the select one of the base member, the seat support structure, the back support structure and the control link, adjusts the biasing torque between the first and second magnitude.

8. The control assembly of claim 5, wherein the resilient biasing member generates a force acting on the movable input member in a first direction, and wherein the adjustment assembly includes an adjustment assist assembly exerting an assist force acting on the movable input member in a second direction substantially opposite to the first direction, thereby reducing an input force required to be applied by a user to the movable input member to adjust the biasing force from the first magnitude to the second magnitude.

9. The control assembly of claim 8, wherein the adjustment assist assembly includes a spring member.

10. The control assembly of claim 3, wherein the adjustment assembly includes first and second threaded members, and wherein rotation of the first threaded member adjusts the biasing force between the first and second magnitudes.

11. A control assembly for a chair, comprising:

a base structure adapted to be attached to a ground-abutting base support structure;

a seat support structure operably coupled to the base structure, wherein the seat support structure is adapted to support a seated user thereon;

a back support structure operably coupled to the base structure, wherein the back support structure is adapted to move between a first position and a second position;

at least one biasing assembly exerting a biasing force that biases the back support structure from the second position towards the first position, wherein the biasing force is adjustable between first and second magnitudes when the back support structure is in the first position, and wherein the second magnitude is greater than the first magnitude; and

an adjustment assist assembly exerting an assist force on the biasing assembly, thereby reducing an input force required to be applied by a user to adjust the biasing force between the first and second magnitudes.

12. The control assembly of claim 11, further comprising:

an adjustment assembly operably coupled to the at least one biasing assembly to adjust the biasing force between the first and second magnitudes, wherein the adjustment assembly adjusts the at least one biasing assembly between a first configuration corresponding to the first magnitude of the biasing force and a second configuration corresponding to the second magnitude of the biasing force.

13. The control assembly of claim 12, wherein the adjustment assembly includes a movable input member that changes the magnitude of the biasing force upon movement of the movable input member between a first position and a second position.

14. The control assembly of claim 13, wherein the biasing force is generated by a resilient biasing member that shifts between a first shape corresponding to the first magnitude of the biasing force and a second shape corresponding to the second magnitude of the biasing force.

15. The control assembly of claim 14, wherein the resilient biasing member comprises a spring member having a first end, a second end and a length defined between the first end and the second end, and wherein a change in the length of the spring member changes the magnitude of the biasing force between the first and second magnitudes.

16. The control assembly of claim 15, wherein the first end of the spring member is operably connected to at least a select one of the base structure, the seat support structure, the back support structure and the control link, and wherein a change of a position of the second end of the spring member relative to the select one of the base member, the seat support structure, the back support structure and the control link, adjusts the biasing force between the first and second magnitude.

17. The control assembly of claim 14, wherein the resilient biasing member generates a force acting on the movable input member in a first direction, and wherein the adjustment assist assembly exerts the assist force on the movable input member in a second direction substantially opposite to the first direction, thereby reducing the input force required to be applied by a user to the movable input member to adjust the biasing force from the first magnitude to the second magnitude.

18. The control assembly of claim 17, wherein the adjustment assist assembly includes a spring member.

19. The control assembly of claim 18, wherein the spring member comprises a coil spring.

20. The control assembly of claim 12, wherein the adjustment assembly includes first and second threaded members, and wherein rotation of the first threaded member adjusts the biasing force between the first and second magnitudes.