A chair includes a seat surface and a laterally pivotable backrest. The backrest is secured to two joints, which have mutually parallel axes of rotation.

A backrest portion supported, such as to be pivotable around an axis extending along its width direction center line, by a base, a left arm holding portion projecting forward from a left side portion of the backrest portion and supported, such as to be pivotable up and down around its base end portion, by the backrest portion, a right arm holding portion projecting forward from a right side portion of the backrest portion and supported, such as to be pivotable up and down around its base end portion, by the backrest portion, a left leg holding portion extending downward from a vicinity of a left side portion of a front edge of a seat portion at a front side of the base and supported, such as to be pivotable up and down around its upper end portion, by the base, and a right leg holding portion extending downward from a vicinity of a right side portion of the front edge of the seat portion at the front side of the base and supported, such as to be pivotable up and down around its upper end portion, by the base are included.

A reconfigurable apparatus for seating a user and having: a frame; a seat movable relative to the frame between: a) a first position in which the seat resides with no user sitting on the seat; and b) a loaded position; a back rest with a changeable angular orientation relative to the frame; and an adjusting assembly having a plurality of gears that move relative to each other as an incident of the seat moving from the first position into the loaded position to thereby cause an increase in resistance to changing of the angular orientation of the back rest.

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. 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 shorten a working length of the leaf spring and provide an increased resistance to tilting of the backrest relative to the column.

A collapsible and portable rocking chair includes left and right frame side assemblies collectively defining forward and rear leg members, armrests, seat support members and back support members. The chair also includes transverse connectors connecting the left and right frame said assemblies and supporting the chair in its set-up condition. The connectors are pivotally connected to one another as well as to the left and right frame side assemblies to facilitate folding of the chair frame to a collapsed and bundled condition where all the frame members are pivoted and/or slid relative to one another to a generally parallel condition. Each frame side assembly is supported on a fulcrum point for rocking movement of the chair frame. A rocker mechanism is attached to the chair frame to support the chair during rocking movement and to facilitate rocking of the chair in connection with the user's shifting weight.

A body support structure includes a frame and a membrane attached to the frame. The membrane includes elastomeric filaments. The membrane includes different regions with different stiffness. The membrane may form a part of a seat or a backrest.

A chair assembly includes a four-bar arrangement that includes a lower end and an upper end where the upper end is adjustable between a raised position and a lowered position, and an arm rest assembly adapted to support the arm of a seated user thereon and supported on an upper end of the four-bar arrangement, wherein the lower end of the four-bar arrangement is pivotably supported from an arm support structure for pivotable movement about an arm pivot axis, such that the upper end of the four-bar arrangement is movable between a first position and second position located laterally outward from the first position, and wherein the arm pivot axis is angularly offset from a vertical axis.

A chair assembly includes an arm assembly that includes an armrest supported by a vertically adjustable support assembly and an arm base, where the arm base extends at an acute angle with respect to a longitudinal centerline of the chair assembly, an upholstery arrangement including a ring member attached to a cover, where the ring member includes a plurality of reliefs having a width that reduces as the ring member is wrapped about a shell member of the chair assembly, and a control arrangement having a biasing member that moves through an arcuate path as the biasing member is adjusted between varying bias settings.

A body support structure includes a frame and a membrane attached to the frame. The membrane includes elastomeric filaments. The membrane includes different regions with different stiffness. The membrane may form a part of a seat or a backrest.

A tilting mechanism (1) for chairs includes a support frame (2), a structure (4) rotationally coupled to the support frame. An elastic system (80) is interposed between the support frame and the structure to counteract a reaction to the tilting of the structure from an at-rest position to a tilted position. An adjustment system (20) is capable of varying the reaction to the tilting. The elastic system (80) includes at least one elastic element (12) and a first and a second stop element (81, 82) fastened at respective longitudinal end portions of the elastic element, respectively. In the at-rest position, the first and second stop elements are in contact with each other, and the elastic element (12) is in a deformed configuration and generates a residual elastic force that is at least partially released on the first and second stop elements.