A reconfigurable apparatus for sitting and having a seat mounted on a frame and movable under the weight of a sitting user. As an incident of the user sitting, resistance to movement of a back rest component is increased a predetermined amount based upon the user's weight. A manually operable subassembly allows the increased resistance to be changed from the predetermined amount with the user sitting on the seat.

Disclosed herein is a chair that includes a backrest portion, a seat portion coupled with the backrest portion, a column portion coupled with the seat portion, a linkage coupled with the backrest portion, a leaf spring in direct contact with the linkage, an arc-shaped toothed structure fixed translationally relative to the column portion, and a different toothed structure in contact with the arc-shaped toothed structure. The chair is also configured such that when a weight is applied to the seat portion, a fulcrum point of the leaf spring moves as the different toothed structure moves along the arc-shaped toothed structure to thereby shorten a working length of the leaf spring and provide an increased resistance to tilting of the backrest portion relative to the column portion. A process for assembling the chair and a weight-based tilt-resistance assembly for use with the chair are also described herein.

A seating assembly includes a seat and an upright coupled with the seat. A pliable backrest is coupled with the upright and includes a support face and a coupling face. The pliable backrest includes a pliable material extending between the support and coupling faces. The support face is a first exterior face of the pliable back rest and the coupling face is a second exterior face of the pliable back rest. The coupling face is spaced away from the upright with a deformation gap. Another seating assembly includes a joint assembly along the upright member. The joint assembly includes a pivot configured to promote rotation of a first upright portion of the upright relative to a second upright portion. The joint assembly includes opposed stop interfaces configured to control rotation of the first upright portion relative to the second upright portion.

Disclosed herein is a chair that includes a backrest portion, a seat portion coupled with the backrest portion, a column portion coupled with the seat portion, a linkage coupled with the backrest portion, a leaf spring in direct contact with the linkage, an arc-shaped toothed structure fixed translationally relative to the column portion, and a different toothed structure in contact with the arc-shaped toothed structure. The chair is also configured such that when a weight is applied to the seat portion, a fulcrum point of the leaf spring moves as the different toothed structure moves along the arc-shaped toothed structure to thereby shorten a working length of the leaf spring and provide an increased resistance to tilting of the backrest portion relative to the column portion. A process for assembling the chair and a weight-based tilt-resistance assembly for use with the chair are also described herein.

A seating assembly includes a seat and an upright coupled with the seat. A pliable backrest is coupled with the upright and includes a support face and a coupling face. The pliable backrest includes a pliable material extending between the support and coupling faces. The support face is a first exterior face of the pliable back rest and the coupling face is a second exterior face of the pliable back rest. The coupling face is spaced away from the upright with a deformation gap. Another seating assembly includes a joint assembly along the upright member. The joint assembly includes a pivot configured to promote rotation of a first upright portion of the upright relative to a second upright portion. The joint assembly includes opposed stop interfaces configured to control rotation of the first upright portion relative to the second upright portion.

Disclosed herein is a reconfigurable apparatus that includes a backrest, a seat coupled with a column, a linkage statically attached to the backrest, a leaf spring in direct contact with the linkage, a first structure fixed to the column, and a second structure. The first and second structures each have one or more teeth. The chair is also configured such that when a weight is applied to the seat, the one or more teeth of the second structure move along the one or more teeth of the first structure to thereby shorten a working length of the leaf spring and provide an increased resistance to tilting of the backrest relative to the column. A process for assembling the reconfigurable apparatus is also described herein.

A chair, comprising, a backrest, a seat coupled with the backrest, a column coupled with the seat, a linkage statically attached to the backrest and rotatably attached below the seat, a leaf spring statically attached at one end and in direct contact with the linkage to provide a resistance to tilting of the backrest relative to the column. A first structure fixed to the column, where a portion of the first structure has an arc shape that includes one or more teeth, and a second structure in contact with the first structure, wherein a portion of the second structure includes one or more teeth. The chair is configured such that, when a weight is applied to the seat, the one or more teeth of the second structure, a pivot point at which the backrest is configured to tilt relative to the column, and the linkage are configured to move together.

A body support structure includes a base, a seat and a backrest, with the backrest connected to the base with a torsion leaf spring. The torsion leaf spring may be configured with a plurality of fingers, and/or one or more flex regions. One or more struts may be connected between the seat or backrest and the base. In another aspect, the seat and/or backrest may be supported with one or more links that provide a counter-intuitive motion. In another aspect, a link may be coupled to a support with a flexible blade.

A chair, comprising, a backrest, a seat coupled with the backrest, a column coupled with the seat, a linkage statically attached to the backrest and rotatably attached below the seat, a leaf spring statically attached at one end and in contact with the linkage to provide a resistance to tilting of the backrest relative to the column, a first structure. A portion of the first structure has an arc shape that includes one or more teeth, and a second structure in contact with the first structure. The chair is configured such that, when a weight is applied to the seat, one or more teeth of the second structure move along the one or more teeth of the first structure to provide an increased resistance to tilting of the backrest relative to the column.

Disclosed herein is a chair that includes a backrest portion, a seat portion coupled with the backrest portion, a column portion coupled with the seat portion, a linkage coupled with the backrest portion, a leaf spring in direct contact with the linkage, an arc-shaped toothed structure fixed translationally relative to the column portion, and a different toothed structure in contact with the arc-shaped toothed structure. The chair is also configured such that when a weight is applied to the seat portion, a fulcrum point of the leaf spring moves as the different toothed structure moves along the arc-shaped toothed structure to thereby shorten a working length of the leaf spring and provide an increased resistance to tilting of the backrest portion relative to the column portion. A process for assembling the chair and a weight-based tilt-resistance assembly for use with the chair are also described herein.