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.

A stowaway compact rocker having a set-up condition and a collapsed and bundled condition comprises a stationary chair frame base; a movable seating chair frame adapted for rocking movement relative to the stationary chair frame base; and a rocker mechanism operatively connected between the stationary chair frame base and the movable seating chair frame. The stationary chair frame base comprises a central axle tube; a pair of leg plates disposed on the central axle tube; front leg tubes; and rear legs tubes, each leg tube being adapted for connection to a leg plate. The movable seating chair frame comprises a pair of seat tube plates mounted on the central axle tube for rotation thereabout; seat member tubes, each being adapted for connection to a respective one of the seat tube plates; and back-rest tubes, each being adapted for connection to a respective one of the seat tube plates.

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 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 rebounding device includes a front member, a rear member, and a spring mechanism including a first biasing element and force adjustment assembly. The force adjustment assembly includes a spring element including a front planar surface and a rear planar surface connected at a rounded portion, wherein the front planar surface contacts an inner surface of the front member; a screw housing secured to an inner surface of the rear member, wherein the screw housing includes a longitudinal channel and a bore on an upper surface; a drive screw positioned through the bore and along the longitudinal channel of the screw housing; a threaded block positioned within the longitudinal channel of the screw housing, wherein the threaded block is configured to move vertically along the longitudinal channel, and wherein the rear planar surface of the spring element is secured to the threaded block.

A chair back, belonging to the field of office furniture, comprises a stretching mechanism, and a supporting mechanism including a supporting frame, an adjusting lever and a rotor disposed on the supporting frame, a spring disposed on the adjusting lever, and a rope wound across the rotor and having an end connected to the spring and an end connected to the stretching mechanism. A sliding slot is formed in the supporting frame. An adjusting block sliding along the sliding slot is disposed in the sliding slot and connected to the adjusting lever in a threaded manner, and has a side abutting against one end of the spring. The stretching mechanism can elastically change to some extent in the stretching direction thereof, so that when moving in this direction, the back of a user will always cling to the backrest, and thus, the user feels more comfortably

A chair includes a seat, a backrest, and an elastic link. The seat supports a user's buttocks, wherein the backrest supports the user's back, the elastic link elastically connects a side portion of the seat to a side portion of the backrest, the seat includes a seat free end formed at a rear portion thereof without being connected to the backrest and the backrest includes a backrest free end formed at a lower portion thereof without being connected to the seat.