TILT MECHANISM FOR A CHAIR AND CHAIR

• US 20140300158A1
• Filed: 07/01/2011
• Published: 10/09/2014
• Est. Priority Date: 07/01/2011
• Status: Active Grant

• Current Assignee: L&P Property Management Company (Leggett & Platt Incorporated)
• Original Assignee: Alessandro Slongo
• Inventors: Jones, Mark Grant, Costaglia, Massimo, Slongo, Alessandro
• Granted Patent: US 9,277,821 B2
• Time in Patent Office: Days
• US Class Current: 297/303.1
• 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 1/03238 by means of peg-and-notch or pawl-and-ratchet mechanism
• CPC Class Codes: A47C 1/03255 with a central column, e.g. rocking office chairs
• CPC Class Codes: A47C 1/03266 with adjustable elasticity
• CPC Class Codes: A47C 1/03272 with coil springs
• CPC Class Codes: A47C 1/03294 slidingly movable in the base frame, e.g. by rollers
• CPC Class Codes: A47C 7/462 adjustable by mechanical means

Abstract

A tilt mechanism is configured for adjustment of a tension applied by a chair back. The tilt mechanism includes a base, a back bracket tiltably supported on the base, and a rocker coupled to the back bracket so as to be moveable relative to the back bracket. The rocker has a pivot axis and pivots about the pivot axis when the back bracket tilts relative to the base. An energy storage mechanism is coupled to the rocker to exert a force onto a portion of the rocker. An actuating mechanism is coupled to at least one of the rocker or the energy storage mechanism and is configured to alter a distance between the pivot axis and the portion of the rocker at which the force is exerted onto the rocker, thereby altering a length of a lever arm.

Claims

1. A tilt mechanism for a chair, said tilt mechanism being configured for adjustment of a tension applied by a chair back, said tilt mechanism comprising:

a base,

a back bracket tiltably supported on said base and configured to be attached to said chair back,

a rocker having a pivot axis provided at a fixed location relative to said rocker, said rocker being coupled to said back bracket so as to be moveable relative to said back bracket and being configured such that said rocker pivots about said pivot axis when said back bracket tilts relative to said base,

an energy storage mechanism coupled to said rocker to exert a force onto a portion of said rocker which portion is spaced from said pivot axis by a distance, and

an actuating mechanism coupled to at least one of said rocker or said energy storage mechanism and configured to alter said distance between said pivot axis and said portion of said rocker at which said force is exerted onto said rocker.

2. The tilt mechanism of claim 1, wherein

said actuating mechanism is configured to effect a relative displacement between said rocker and said energy storage mechanism.

3. The tilt mechanism of claim 2, wherein

said actuating mechanism is configured to effect a translational displacement of at least one of said pivot axis of said rocker or said energy storage mechanism relative to said base.

4. The tilt mechanism of claim 3, wherein

said energy storage mechanism includes a resiliently deformable member having a deformation axis, and

said actuating mechanism is configured to alter a distance of said deformation axis from said pivot axis.

5. The tilt mechanism of claim 3, comprising

a guide, in particular a linear guide, to guide said translational displacement.

6. The tilt mechanism of claim 5, wherein

said tilt mechanism defines a forward-backward direction, and

said guide extends in said forward-backward direction.

7. The tilt mechanism of claim 2, wherein

said rocker has an interface section slideably engaged with said energy storage mechanism and configured to remain engaged with said energy storage mechanism when said actuating mechanism effects said relative displacement.

8. The tilt mechanism of claim 1,

wherein said back bracket so as to be tiltable about a tilt axis, said tilt axis being parallel to and spaced from said pivot axis.

9. The tilt mechanism of claim 8, wherein

said rocker exerts a further force onto said back bracket, and

said actuating mechanism is configured to alter a length of a lever arm of said further force relative to said tilt axis.

10. The tilt mechanism of claim 8, wherein

said rocker has a coupling section engaged with said back bracket, and

said actuating mechanism is configured to, upon actuation of said actuating mechanism, displace said coupling section relative to said base.

11. The tilt mechanism of claim 10, wherein

said actuating mechanism is configured

to displace said coupling section away from a plane in which said tilt axis is located and to simultaneously increase said distance between said pivot axis and said portion of said rocker, when said actuating mechanism is actuated in a first direction, and

to displace said coupling section towards said plane in which said tilt axis is located and to simultaneously decrease said distance between said pivot axis and said portion of said rocker, when said actuating mechanism is actuated in a second direction opposite to said first direction.

12. The tilt mechanism of claim 8, wherein

said rocker has a coupling section engaged with said back bracket, and

said actuating mechanism is configured to, upon actuation of said actuating mechanism, alter an angle between a line connecting said coupling section and said pivot axis and another line connecting said coupling section and said tilt axis.

13. The tilt mechanism of claim 12, wherein

said actuating mechanism is configured

to decrease said angle and to simultaneously increase said distance between said pivot axis and portion of said rocker, when said actuating mechanism is actuated in a first direction, and

to increase said angle and to simultaneously decrease said distance between said pivot axis and said portion of said rocker, when said actuating mechanism is actuated in a second direction opposite to said first direction.

14. The tilt mechanism of claim 1, wherein

said energy storage mechanism includes a resiliently deformable member and a deformation guide guiding a deformation movement of said resiliently deformable member, said deformation guide being attached to said base.

15. The tilt mechanism of claim 14, wherein

said base extends in a forward-backward direction of said tilt mechanism from a first end to a second end, and

said deformation guide is attached to said base so as to be spaced from said first end and said second end of said base.

16. The tilt mechanism of claim 14, comprising

a setting mechanism,

wherein said deformation guide has a deformation guide axis along which said resiliently deformable member deforms, said setting mechanism being configured to adjust an orientation of said deformation guide axis relative to said base.

17. The tilt mechanism of claim 14, wherein

said deformation guide supports opposite axial ends of said resiliently deformable member.

18. The tilt mechanism of claim 1, wherein

said rocker includes a first rocker member and a second rock member, said first and second rocker members being spaced from each other in a direction parallel to said pivot axis.

19. The tilt mechanism of claim 1, comprising

a seat support moveably supported on said base and configured to be attached to a chair seat, and

a linkage coupling said seat support to at least one of said rocker or said back bracket.

20. The tilt mechanism of claim 1, wherein

said actuating mechanism has a manually operable actuating element and is configured such that less than five full 360°

turns, in particular less than one full 360°

turn, of said actuating element are required to alter said distance between said pivot axis and said portion of said rocker at which said force is exerted onto said rocker from a maximum distance to a minimum distance.

21. A chair, comprising

a chair base assembly,

a chair seat,

a chair back, and

a tilt mechanism according to claim 1, said base of said tilt mechanism being attached to said chair base assembly and said chair back being affixed to said back bracket.