Ergonomic chair

• US 6,669,292 B2
• Filed: 02/15/2002
• Issued: 12/30/2003
• Est. Priority Date: 06/15/2001
• Status: Expired due to Fees

• Current Assignee: HNI Technologies Inc. (HNI Corporation)
• Original Assignee: Hon. Technologies, Inc.
• Inventors: Phillips, Matthew J., Trego, Brian R., Machael, Jay R., Koepke, Marcus C., Schultz, Craig H., Steffensen, Erik A., Coffield, Tim, Schroeder, Douglas A., Habboub, Amin K., Davis, Keith L., Zillig, Eric M., Krull, Jamie
• Primary Examiner(s): WHITE, RODNEY BARNETT
• Application Number:
  US10/077,409
• Publication Number:
  US 20030001420A1
• Time in Patent Office: 683 Days
• Field of Search: 297/300.2, 297/300.1, 297/322
• US Class Current: 297/300.2
• CPC Class Codes: A47C 1/03255 with a central column, e.g. rocking office chairs
• CPC Class Codes: A47C 31/126 for chairs
• CPC Class Codes: A47C 7/282 with mesh-like supports, e.g. elastomeric membranes
• CPC Class Codes: A47C 7/46 with special, e.g. adjustable , lumbar region support profile; "Ackerblom" profile chairs

Abstract

An ergonomic chair includes a four-bar linkage arrangement wherein a lower frame member is provided with a rigid front support and a rigid rear support with a seat member pivotably connected to the front support. A back rest has an upper support pivotably connected at an upper end of the rear support of the lower frame member. A link member pivotably connects at a first end to a rear support of the seat member and at second end to a lower support of the back rest. This novel arrangement permits tilting movement of the backrest rearwardly relative to the lower frame member causing elevation of a rear portion of the seat member, permitting the feet to remain on the floor and alleviating pressure on the user'"'"'s thighs, while rotation occurs closely coincident with the pivot axis of the user'"'"'s hips and while maintaining a generally uniform gaze line.

Claims

1. A chair comprising:

support frame means having a forward first support portion and a rear second support portion, said support frame means including a pair of spaced elongated rigid support members connected to opposite sides of a central base module and defining said forward and rear support portions;

a seat member pivotably connected at its forward end to said first forward support portion of said frame means and having a rear support portion;

a backrest member having first and second pivot locations, said first pivot location of said backrest member being pivotably connected to said rear second support portion of said frame means, said backrest member comprising a skeletal frame having a pair of spaced uprights, and a lower transverse member having opposite ends and the rear ends of each of said second support portion being pivotally connected to said transverse frame member; and

a link member pivotably connected to said rear support portion of said seat member and pivotably connected to said second pivot location of said backrest member;

wherein tilting movement of said backrest member rearwardly relative to said frame means causes elevation of said rear portion of said seat member upon weight shifting of the chair user and wherein said seat member and said backrest member have a relative center of rotation approximately coincident with the center of rotation of the hip joint of the user.

2. The chair of claim 1 wherein a carrier is attached to said spaced uprights and said transverse member and said carrier includes a fabric backrest attached thereto.

3. The chair of claim 2 further comprising a lumbar member disposed on said skeletal frame and disposed horizontally across the back of said carrier at approximately the lumbar region of a back of a user, said lumbar member being positioned to provide a desired pressure location to help support the back of the user.

4. The chair of claim 3 wherein said lumbar member is height adjustable regardless of the inclination of said chair back.

10. The chair of claim 1 wherein said seat member in a rest position is inclined downwardly toward the rear of said chair.

11. The chair of claim 10, wherein in a fully upright position of said backrest member said seat member is inclined to the rear of the chair at an angle in a range of between about 10 and 20 degrees from horizontal.

12. The chair of claim 10 wherein in a fully upright position of said backrest member said seat member is inclined to the rear of the chair at an angle of about 15.7 degrees from horizontal.

13. The chair of claim 10 wherein in a fully reclined position of said backrest member said seat member is inclined to the rear of the chair at an angle in a range of between about 6 and 10 degrees.

14. The chair of claim 10 wherein in a fully reclined position of said backrest member said seat member is inclined to the rear of the chair at an angle of about 8.7 degrees from horizontal.

15. The chair of claim 1 wherein the distance between the pivotable connection of said seat member and said first support portion to the pivotable connection of said link member and said rear support of said seat member is in a range of between 10 and 15 inches.

16. The chair of claim 15 wherein the distance between the pivotable connection of said seat member and first support portion to the pivotable connection of said link member and the rear support of said seat member is approximately 12.889 inches.

17. The chair of claim 1 wherein the horizontal distance between said first support portion of said frame means and the upper end of the second rear support portion of the frame means is in a range of between about 12 and 17 inches.

18. The chair of claim 1 wherein the horizontal distance between the first forward support portion of said frame means and the upper end of the second rear support portion of said frame means is approximately 14.5 inches.

19. The chair of claim 1 wherein the distance between the pivotable connections of said link member is in a range of between about 1.5 to 2.5 inches.

20. The chair of claim 19 wherein the distance between the pivotable connections of said link member is about 2.01 inches.

21. The chair of claim 1 wherein the distance between the said second pivot location of said back rest member and said link member pivotable connection thereto is in a range of between about 3 and 6 inches.

22. The chair of claim 21 wherein the distance between said second pivot location of said backrest member and said link member pivotable connection thereto is about 4.7 inches.

5. A chair comprising:

support frame means having a forward first support portion and a rear second support portion;

a seat member pivotably connected at its forward end to said first forward support portion of said frame means and having a rear support portion;

a backrest member having first and second pivot locations, said first pivot location of said backrest member being pivotably connected to said rear second support portion of said frame means, said backrest member comprising a fabric of elastic material disposed in a carrier mounted on a skeletal back assembly to provide a support which generally conforms to the back of a user when the chair is in any tilt position; and

a link member pivotably connected to said rear support portion of said seat member and pivotably connected to said second pivot location of said backrest member;

wherein tilting movement of said backrest member rearwardly relative to said frame means causes elevation of said rear portion of said seat member upon weight shifting of the chair user and wherein said seat member and said backrest member have a relative center of rotation approximately coincident with the center of rotation of the hip joint of the user.

6. A chair comprising:

support frame means having a forward first support portion and a rear second support portion;

a seat member pivotably connected at its forward end to said first forward support portion of said frame means and having a rear support portion, said seat member including a cushion portion which is independently movable in a relatively horizontal direction relative to said backrest member, whereby a user may configure said seat member in a desired position relative to said back member for greater comfort;

a backrest member having first and second pivot locations, said first pivot location of said backrest member being pivotably connected to said rear second support portion of said frame means; and

a link member pivotably connected to said rear support portion of said seat member and pivotably connected to said second pivot location of said backrest member;

wherein tilting movement of said backrest member rearwardly relative to said frame means causes elevation of said rear portion of said seat member upon weight shifting of the chair user and wherein said seat member and said backrest member have a relative center of rotation approximately coincident with the center of rotation of the hip joint of the user.

7. A chair comprising:

support frame means having a forward first support portion and a rear second support portion, said support frame means comprising a transverse central support module, a pair of spaced forwardly extending seat support means carried by said central module and a pair of spaced rearwardly extending backrest support means carried by said module; and

a seat member pivotably connected at its forward end to said first forward support portion of said frame means and having a rear support portion;

a backrest member having first and second pivot locations, said first pivot location of said backrest member being pivotably connected to said rear second support portion of said frame means; and

a link member pivotably connected to said rear support portion of said seat member and pivotably connected to said second pivot location of said backrest member;

wherein tilting movement of said backrest member rearwardly relative to said frame means causes elevation of said rear portion of said seat member upon weight shifting of the chair user and wherein said seat member and said backrest member have a relative center of rotation approximately coincident with the center of rotation of the hip joint of the user.

8. The chair of claim 7, wherein each said pair of seat support means and back support means comprises a unitary member fixedly secured to said central support module.

9. A chair comprising:

support frame means having a forward first support portion and a rear second support portion;

a seat member pivotably connected at its forward end to said first forward support portion of said frame means and having a rear support portion;

a backrest member having first and second pivot locations, said first pivot location of said backrest member being pivotably connected to said rear second support portion of said frame means;

a link member pivotably connected to said rear support portion of said seat member and pivotably connected to said second pivot location of said backrest member; and

a pair of armrests on opposite sides of said seat member, said armrests being height adjustable;

wherein tilting movement of said backrest member rearwardly relative to said frame means causes elevation of said rear portion of said seat member upon weight shifting of the chair user and wherein said seat member and said backrest member have a relative center of rotation approximately coincident with the center of rotation of the hip joint of the user.

23. A chair comprising:

support frame means having a forward first support portion and a rear second support portion;

a seat member pivotably connected at its forward end to said first forward support portion of said frame means and having a rear support portion;

a backrest member having first and second pivot locations, said first pivot location of said backrest member being pivotably connected to said rear second support portion of said frame means;

a link member pivotably connected to said rear support portion of said seat member and pivotably connected to said second pivot location of said backrest member; and

at least one extension spring connected between said rear support portion of said seat member and said backrest member, thereby to urge said backrest toward an upright position;

wherein tilting movement of said backrest member rearwardly relative to said frame means causes elevation of said rear portion of said seat member upon weight shifting of the chair user and wherein said seat member and said backrest member have a relative center of rotation approximately coincident with the center of rotation of the hip joint of the user.

24. A tiltable chair comprising:

a base member;

a seat member, said seat member including a cushion comprising an assembly of a rigid seat pan, a foam layer, a plurality of spaced foam risers defining a plenum, an elastomeric member overlying said risers, an air permeable layer overlying said elastomeric layer, and a fabric covering said layers;

a backrest member; and

a linkage assembly connecting said seat member and said back member to said base member, said linkage assembly being configured and arranged to allow a rear portion of said seat to rise and concurrently said back member to tilt downwardly and rearwardly, with pivotal movement of said seat member relative to said back member occurring about a pivot axis substantially in alignment with the hip joints of a user.

25. A tiltable chair comprising:

a base member;

a seat member;

a backrest member;

a pair of armrest assemblies disposed on said base member on opposite sides of said seat member, said armrest assemblies remaining in substantially the same attitude regardless of the angle of inclination of said back member or said seat member during tilting of said chair; and

a linkage assembly connecting said seat member and said back member to said base member, said linkage assembly being configured and arranged to allow a rear portion of said seat to rise and concurrently said back member to tilt downwardly and rearwardly, with pivotal movement of said seat member relative to said back member occurring about a pivot axis substantially in alignment with the hip joints of a user.

26. The chair of claim 25 wherein each said armrest is rotatable about an axis adjacent a corresponding side edge portion of the back, said axes being positioned for approximate alignment with the elbows of a user having forearms resting on said armrests.

29. The chair of claim 25 and further including a pair of height adjustable armrests adapted to rotate laterally in a substantially horizontal plane to accommodate the angle at which the forearms of a user are positioned.

27. A tiltable chair comprising:

a base member;

a seat member;

a backrest member, said backrest member comprising a skeletal frame having a carrier affixed thereto, said carrier having a fabric disposed therein for contact with the back of the user; and

a linkage assembly connecting said seat member and said back member to said base member, said linkage assembly being configured and arranged to allow a rear portion of said seat to rise and concurrently said back member to tilt downwardly and rearwardly, with pivotal movement of said seat member relative to said back member occurring about a pivot axis substantially in alignment with the hip joints of a user.

28. A tiltable chair comprising:

a base member;

a seat member;

a backrest member;

a height adjustable lumbar member positioned horizontally across said back member at approximately the lumbar region of a back of a user, said lumbar member being height adjustable by the user; and

a linkage assembly connecting said seat member and said back member to said base member, said linkage assembly being configured and arranged to allow a rear portion of said seat to rise and concurrently said back member to tilt downwardly and rearwardly, with pivotal movement of said seat member relative to said back member occurring about a pivot axis substantially in alignment with the hip joints of a user.

30. A tiltable chair comprising:

a base member;

a seat member;

a backrest member;

adjustable tilt limiting means whereby the user may selectively predetermine the maximum amount of inclination of said chair back; and

a linkage assembly connecting said seat member and said back member to said base member, said linkage assembly being configured and arranged to allow a rear portion of said seat to rise and concurrently said back member to tilt downwardly and rearwardly, with pivotal movement of said seat member relative to said back member occurring about a pivot axis substantially in alignment with the hip joints of a user.