Abstract: A chair assembly includes a base structure defining upper and lower portions, and a support structure, a seat support structure having a forward portion pivotably connected to the upper portion of the base structure for rotation about a first pivot point and a rearward portion, a back support structure having a forward portion pivotably connected to the lower portion of the base structure for rotation about a second pivot point that is located below and rearward of the first pivot point, and an upwardly extending back portion that moves rearwardly and downwardly as the back support structure pivots and the back portion moves, and a control link pivotably coupled to the seat support structure for rotation about a third pivot point and to the back support structure for rotation about a fourth pivot point each located rearward of the first and second pivot points.

Abstract: A seating arrangement includes a base support, a support arrangement movable between upright and reclined positions, and a spring arrangement that includes a first portion attached to the support arrangement, a second portion attached to the base support, an intermediate portion positioned between the first and second positions, first and second members configured to bias the support arrangement from the reclined position toward the upright position, the second spring member spaced from the first spring member, and an adjustment member positioned between the first and intermediate portions, the adjustment member adjustable between positions that adjust the force exerted by the first and second spring on the support arrangement.

Abstract: A chair assembly includes a base structure defining upper and lower portions, and a support structure, a seat support structure having a forward portion pivotably connected to the upper portion of the base structure for rotation about a first pivot point and a rearward portion, a back support structure having a forward portion pivotably connected to the lower portion of the base structure for rotation about a second pivot point that is located below and rearward of the first pivot point, and an upwardly extending back portion that moves rearwardly and downwardly as the back support structure pivots and the back portion moves, and a control link pivotably coupled to the seat support structure for rotation about a third pivot point and to the back support structure for rotation about a fourth pivot point each located rearward of the first and second pivot points.

Abstract: A chair assembly includes a base structure, a seat support structure pivotably coupled to the base structure, and a back support structure pivotably coupled to the base structure and including an upwardly-extending portion adapted to move between upright and reclined positions and a lower portion extending forwardly of the upwardly-extending portion, and wherein the upwardly-extending portion is operably coupled to the forwardly-extending portion by a first quick connect assembly. The chair assembly further includes a generally forwardly-facing back support assembly and having an upper portion operably coupled to the upwardly-extending portion of the back support and a lower portion, and a back link releasably coupled to the lower portion of the back support surface by a second quick connect assembly and operably coupled to the seat support structure.

Abstract: A chair assembly includes a four-bar linkage assembly including a first linkage member, a second linkage member, a third linkage member and a fourth linkage member each pivotably coupled to one another such that the four-bar linkage assembly includes an upper end that is adjustable between raised and lowered positions, and an arm rest assembly adapted to support the arm of a seated user thereon and supported the upper end of the four-bar linkage assembly, wherein a lower end of the four-bar linkage assembly is pivotably supported from an arm support structure for pivotable movement, such that the upper end of the four-bar linkage assembly is moveable between a first position and second position located laterally outward from the first position and wherein the arm support structure is fixed with respect to the seat support structure.

Abstract: A seating arrangement includes a base support, a support arrangement movable between upright and reclined positions, and a spring arrangement that includes a first portion attached to the support arrangement, a second portion attached to the base support, an intermediate portion positioned between the first and second positions, first and second members configured to bias the support arrangement from the reclined position toward the upright position, the second spring member spaced from the first spring member, and an adjustment member positioned between the first and intermediate portions, the adjustment member adjustable between positions that adjust the force exerted by the first and second spring on the support arrangement.

Abstract: A chair assembly includes a base structure, a seat support structure pivotably coupled to the base structure, and a back support structure pivotably coupled to the base structure and including an upwardly-extending portion adapted to move between upright and reclined positions and a lower portion extending forwardly of the upwardly-extending portion, and wherein the upwardly-extending portion is operably coupled to the forwardly-extending portion by a first quick connect assembly. The chair assembly further includes a generally forwardly-facing back support assembly and having an upper portion operably coupled to the upwardly-extending portion of the back support and a lower portion, and a back link releasably coupled to the lower portion of the back support surface by a second quick connect assembly and operably coupled to the seat support structure.

Abstract: A chair assembly includes a four-bar linkage assembly including a first linkage member, a second linkage member, a third linkage member and a fourth linkage member each pivotably coupled to one another such that the four-bar linkage assembly includes an upper end that is adjustable between raised and lowered positions, and an arm rest assembly adapted to support the arm of a seated user thereon and supported the upper end of the four-bar linkage assembly, wherein a lower end of the four-bar linkage assembly is pivotably supported from an arm support structure for pivotable movement, such that the upper end of the four-bar linkage assembly is moveable between a first position and second position located laterally outward from the first position and wherein the arm support structure is fixed with respect to the seat support structure.

Abstract: A chair assembly includes a base structure, a seat support structure movably coupled to the base structure, an upwardly-extending back support structure movably coupled to the base structure, wherein the back support structure is adapted to move between an upright and reclined positions, wherein the back support structure is operably coupled to the seat support structure, a flexible shell structure defining a forwardly-facing surface forming a lumbar support, wherein the flexible shell is movably coupled to the seat support structure, and a resilient member generating a variable compressive force acting on the flexible shell structure in a manner that tends to cause a curvature of the back support structure to increase, and wherein the compressive force decreases as the back support structure moves from the upright position to the reclined position.

Abstract: A chair assembly includes a base structure defining upper and lower portions, a seat support structure having forward and rearward portions, wherein the forward portion of the seat support structure is pivotably coupled to the upper portion, and wherein the seat support structure includes a seat support surface configured to support a seated user thereon, a back support structure having forward and rearward portions, wherein the forward portion of the back supported is pivotably coupled to the lower portion, and wherein the back support structure includes an upwardly extending portion adapted to move between an upright position and a reclined position, and a control link having a first end pivotably coupled to the rearward portion of the seat support structure, and a second end pivotably coupled to the rearward portion of the back support structure.

Abstract: A chair assembly includes a four-bar linkage assembly including a first linkage member, a second linkage member, a third linkage member and a fourth linkage member each pivotably coupled to one another such that the four-bar linkage assembly includes an upper end that is adjustable between raised and lowered positions, and an arm rest assembly adapted to support the arm of a seated user thereon and supported the upper end of the four-bar linkage assembly, wherein a lower end of the four-bar linkage assembly is pivotably supported from an arm support structure for pivotable movement, such that the upper end of the four-bar linkage assembly is moveable between a first position and second position located laterally outward from the first position.

Abstract: A chair assembly includes a base structure, a seat support structure pivotably coupled to the base structure, a back support structure pivotably coupled to the base structure and including an upwardly extending portion adapted to move between an upright position and a reclined position, a control link having a first end pivotably coupled to the seat support structure and a second end pivotably coupled to the back support structure, a back support surface having an upper portion pivotably coupled to the back support, and a back link pivotably coupled to the seat support structure, wherein the back support surface is moved forward by the back link relative to the upwardly extending portion of the back support structure as the back support structure is moved from the upright position to the reclined position.

Abstract: A chair assembly includes a four-bar linkage assembly including a first linkage member and a second linkage member each having a U-shaped cross-sectional configuration that cooperate to form an interior space, a third linkage member and a fourth linkage member, wherein the linkage members are pivotably coupled to on another such that an upper end of the four-bar linkage is vertically adjustable between a raised and lowered positions, an arm rest assembly supported on the upper end of the four-bar linkage assembly, and a locking assembly including a first locking link having a first surface and a second locking link having plurality of teeth corresponding to a plurality of vertical positions of the four-bar link located between the raised and lowered positions, wherein the locking links are movable between locked and unlocked positions, and wherein the first and second locking links are located within the interior space.

Abstract: A chair assembly includes a base structure defining upper and lower portions, a seat support structure having forward and rearward portions, wherein the forward portion of the seat support structure is pivotably coupled to the upper portion, and wherein the seat support structure includes a seat support surface configured to support a seated user thereon, a back support structure having forward and rearward portions, wherein the forward portion of the back supported is pivotably coupled to the lower portion, and wherein the back support structure includes an upwardly extending portion adapted to move between an upright position and a reclined position, and a control link having a first end pivotably coupled to the rearward portion of the seat support structure, and a second end pivotably coupled to the rearward portion of the back support structure.

Abstract: A chair assembly includes a base structure, a seat support structure movably coupled to the base structure, an upwardly-extending back support structure movably coupled to the base structure, wherein the back support structure is adapted to move between an upright and reclined positions, wherein the back support structure is operably coupled to the seat support structure, a flexible shell structure defining a forwardly-facing surface forming a lumbar support, wherein the flexible shell is movably coupled to the seat support structure, and a resilient member generating a variable compressive force acting on the flexible shell structure in a manner that tends to cause a curvature of the back support structure to increase, and wherein the compressive force decreases as the back support structure moves from the upright position to the reclined position.

Abstract: A chair assembly includes a base structure, a seat support structure pivotably coupled to the base structure, a back support structure pivotably coupled to the base structure and including an upwardly extending portion adapted to move between an upright position and a reclined position, a control link having a first end pivotably coupled to the seat support structure and a second end pivotably coupled to the back support structure, a back support surface having an upper portion pivotably coupled to the back support, and a back link pivotably coupled to the seat support structure, wherein the back support surface is moved forward by the back link relative to the upwardly extending portion of the back support structure as the back support structure is moved from the upright position to the reclined position.

Abstract: A chair assembly includes a four-bar linkage assembly including a first linkage member and a second linkage member each having a U-shaped cross-sectional configuration that cooperate to form an interior space, a third linkage member and a fourth linkage member, wherein the linkage members are pivotably coupled to on another such that an upper end of the four-bar linkage is vertically adjustable between a raised and lowered positions, an arm rest assembly supported on the upper end of the four-bar linkage assembly, and a locking assembly including a first locking link having a first surface and a second locking link having plurality of teeth corresponding to a plurality of vertical positions of the four-bar link located between the raised and lowered positions, wherein the locking links are movable between locked and unlocked positions, and wherein the first and second locking links are located within the interior space.

Abstract: A chair assembly includes a four-bar linkage assembly including a first linkage member, a second linkage member, a third linkage member and a fourth linkage member each pivotably coupled to one another such that the four-bar linkage assembly includes an upper end that is adjustable between raised and lowered positions, and an arm rest assembly adapted to support the arm of a seated user thereon and supported the upper end of the four-bar linkage assembly, wherein a lower end of the four-bar linkage assembly is pivotably supported from an arm support structure for pivotable movement, such that the upper end of the four-bar linkage assembly is moveable between a first position and second position located laterally outward from the first position.