Chairs with flexible spring backrest
AssigneeChokchai Charoenapornwatana
InventorChokchai Charoenapornwatana
Life of this patent
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Abstract
A chair comprises at least a seat assembly, an armrest, a backrest, and a spring linkage. The backrest frame ends are connected to the upstanding back-leg frame ends of the seat assembly by the spring linkages to make a chair with a flexible spring backrest. Each spring linkage is of a U-shaped configuration having two ends spaced vertically apart; the upper end attached to the backrest frame and the lower end attached to the back-legs of the seat assembly. The tip of the spring linkage serves as a pivotal axis, allowing the backrest to be flexible and bend backwards in response to an applied force while returning to its normal position when the force is removed.
Claims41
A chair comprising:
- a seat assembly;
- a backrest frame;
- and
- a number of springs coupling the seat assembly to the backrest frame, the springs torsionally flex along a pivotal axis;
- and
- a number of casings surrounding the springs, in which the casings restrict the springs from bending beyond a predetermined degree.
A spring linkage system for use in a chair, comprising:
- a number of springs configured to connect a backrest frame of the chair to a number of back legs of the chair;
- wherein the springs are of a u-shape,
- wherein the two ends of the u-shaped springs are vertically spaced apart, and
- in which the springs torsionally flex along a pivotal axis located at a distal end of the springs with respect to the two ends of the springs.
A method of manufacturing a reclining chair, comprising:
- forming a seat assembly;
- forming a backrest frame;
- coupling the backrest frame to the seat assembly via a number of springs, in which the springs are coupled to the backrest frame and seat assembly to create a torsional spring force;
- and
- surrounding the springs with a number of casings, in which the casings restrict the springs from bending beyond a predetermined degree.
A method of manufacturing a reclining chair, comprising:
- forming a seat assembly;
- forming a backrest frame;
- coupling the backrest frame to the seat assembly via a number of springs, in which the springs are coupled to the backrest frame and seat assembly to create a torsional spring force;
- surrounding the springs with a number of casings, in which the casings restrict the springs from bending beyond a predetermined degree;
- and
- coupling a column to the seat assembly.
Dependencies are inferred from the claim text.