Chair with backward and forward passive tilt capabilities

• US 6,969,116 B2
• Filed: 12/30/2003
• Issued: 11/29/2005
• Est. Priority Date: 12/30/2003
• Status: Active Grant

• Current Assignee: HNI Technologies Inc. (HNI Corporation)
• Original Assignee: HNI Technologies Inc. (HNI Corporation)
• Inventors: Machael, Jay R., Koepke, Marcus C.
• Primary Examiner(s): Cuomo, Peter M.
• Assistant Examiner(s): EDELL, JOSEPH F
• Application Number:
  US10/749,008
• Publication Number:
  US 20050146184A1
• Time in Patent Office: 700 Days
• Field of Search: 297/300.2, 297/300.4, 297/316, 297/320, 297/340
• 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 1/03261 characterised by elastic means

Abstract

A chair with backward and forward passive tilt capabilities including a seat assembly, a back assembly, a frame assembly, a wheeled base, a pedestal and a tilt mechanism. The tilt mechanism includes first, second and third links, first, second, third and fourth pivot pins, brackets and a resilient deformable block. The first link connects the back assembly with the frame assembly by way of the first pivot pin and the seat assembly by way of the second pivot pin. The second link connects to the frame assembly with the third pivot pin and to the third link with the fourth pivot pin. When a chair occupant shifts his/her weight rearwardly to tilt the back assembly, the seat assembly lifts and the block is deformed and stressed. When the chair occupant leans forwardly, the seat assembly lowers and the back assembly tilts forwardly. Again, the block deforms. Once the occupant sits upright or leaves the chair, the deformed block induces a return force to place the chair in a neutral upright position.

Claims

1. A chair having synchronous movement of back and seat assemblies and backward and forward passive tilt capabilities comprising:

a chair having a seat assembly, a back assembly and a frame assembly for supporting said seat and said back assemblies;

a first link operatively connected to said back assembly, to said frame assembly and to said seat assembly;

a first pivot connecting said frame assembly and said first link wherein said first link pivots relative to said frame assembly;

a second pivot connecting said first link and said seat assembly wherein said first link pivots relative to said seat assembly, whereby said second pivot is approximately located beneath a chair occupant'"'"'s hip joint;

a second link operatively connected to said frame assembly and to a third link;

a third pivot connecting said frame assembly and said second link;

said third link operatively connected to said seat assembly and to said second link;

a fourth pivot connecting said second link and said third link; and

a biasing member mounted to said frame assembly and being deformable;

said first pivot is located more rearwardly and upwardly than said second, third and fourth pivots;

said second pivot is located more rearwardly and upwardly than said third and fourth pivots; and

said third pivot is located more rearward and upwardly than said fourth pivot.

2. A chair having synchronous movement of back and seat assemblies and backward and forward passive tilt capabilities comprising:

a chair having a seat assembly, a back assembly and a frame assembly for supporting said seat and said back assemblies;

a first link operatively connected to said back assembly, to said frame assembly and to said seat assembly;

a first pivot connecting said frame assembly and said first link wherein said first link pivots relative to said frame assembly;

a second pivot connecting said first link and said seat assembly wherein said first link pivots relative to said seat assembly, whereby said second pivot is approximately located beneath a chair occupant'"'"'s hip joint;

a second link operatively connected to said frame assembly and to a third link;

a third pivot connecting said frame assembly and said second link;

said third link operatively connected to said seat assembly and to said second link;

a fourth pivot connecting said second link and said third link; and

a biasing member mounted to said frame assembly and being deformable;

said first pivot is fixed in position relative to said frame assembly;

said second pivot is movable relative to said frame assembly;

said third pivot is fixed in position relative to said frame assembly;

said fourth pivot is movable relative to said frame assembly;

said first pivot is located more rearwardly and upwardly than said second, third and fourth pivots;

said second pivot is located more rearwardly and upwardly than said third and fourth pivots; and

said third pivot is located more rearward and upwardly than said fourth pivot.

3. The chair of claim 2 wherein:

from an upright position a weight shift by a chair occupant causes said seat assembly to tilt downwardly thereby tilting said back assembly forwardly toward said seat assembly; and

from an upright position a weight shift by a chair occupant causes said back assembly to tilt rearwardly and said seat assembly to lift.

4. The chair of claim 3 wherein:

said seat assembly moves at a lesser rate than said back assembly.

5. The chair of claim 3 wherein:

movement of said back assembly causes said first link to move said seat assembly;

movement of said seat assembly pivots said second link; and

pivoting said second link causes said biasing member to deform.

6. The chair of claim 5 wherein:

movement of said seat assembly induces stress in said biasing member.

7. The chair of claim 6 wherein:

movement of said seat assembly from an upright neutral position induces deformation of said biasing member and a biasing force to return said seat assembly to said upright neutral position.

8. The chair of claim 7 wherein:

said first link is connected at a first end portion to said back assembly, at a second end portion to said seat assembly and between said first and second end portions to said center frame; and

said third link is connected at a first end portion to a front portion of said seat assembly and at a second end portion to said second link.

9. A chair having synchronous movement of back and seat assemblies and backward and forward passive tilt capabilities comprising:

a chair having a seat assembly, a back assembly and a frame assembly for supporting said seat and said back assemblies;

a first link operatively connected to said back assembly, to said frame assembly and to said seat assembly;

a first pivot connecting said frame assembly and said first link wherein said first link pivots relative to said frame assembly;

a second pivot connecting said first link and said seat assembly wherein said first link pivots relative to said seat assembly, whereby said second pivot is approximately located beneath a chair occupant'"'"'s hip joint;

a second link operatively connected to said frame assembly and to a third link;

a third pivot connecting said frame assembly and said second link;

said third link operatively connected to said seat assembly and to said second link;

a fourth pivot connecting said second link and said third link; and

a biasing member mounted to said frame assembly and being deformable;

wherein from an upright position a weight shift by a chair occupant causes said seat assembly to tilt downwardly thereby tilting said back assembly forwardly toward said seat assembly;

from an upright position a weight shift by a chair occupant causes said back assembly to tilt rearwardly and said seat assembly to lift;

movement of said back assembly causes said first link to move said seat assembly;

movement of said seat assembly pivots said second link;

pivoting said second link causes said biasing member to deform;

movement of said seat assembly induces stress in said biasing member;

movement of said seat assembly from an upright position induces deformation of said biasing member and a biasing force to return said seat assembly to said upright neutral position;

said first pivot is fixed in position relative to said frame assembly;

said second pivot is movable relative to said frame assembly;

said third pivot is fixed in position relative to said frame assembly;

said fourth pivot is movable relative to said frame assembly;

said first pivot is located more rearwardly and upwardly than said second, third and fourth pivots;

said second pivot is located more rearwardly and upwardly than said third and fourth pivots; and

said third pivot is located more rearward and upwardly than said fourth pivot.

10. The chair of claim 9 wherein:

said first link is connected at a first end portion to said back assembly, at a second end portion to said seat assembly and between said first and second end portions to said frame assembly; and

said third link is connected at a first end portion to a front portion of said seat assembly and at a second end portion to said second link.