A chair for providing seating support to a user and for providing ways for the user to perform exercises. The chair includes a back support that is flexible such that when a force is applied to it by the user's body, the back support bends. The back support may be configured to adapt to the curvature of the user's spine when the user is seated in the chair. The back support may further be configured such that the user can rotate the back support by rotating the user's upper body.

A seat assembly includes a frame made from a first material having a first hardness, the frame including a first side and a second side opposite the first side. The seat assembly further includes a fabric component coupled to the first side of the frame, and a plurality of grooves are disposed within the second side of the frame. Each insert of a plurality of inserts are disposed within each respective groove in the plurality of grooves. Each insert of the plurality of inserts comprises a second material and the second material has a second hardness that is less than the first hardness.

A swingable chair chassis comprises a rocker seat including a chamber defined between a bottom wall and a peripheral wall. The bottom wall includes a slot extending in a front/rear direction. A lid is securely mounted to a bottom of the seat and the rocker seat. A supporting seat is disposed in the chamber of the rocker seat. The supporting seat includes a central portion having an insertion hole coupled with chair post. The supporting seat includes an arcuate supporting face formed on an upper side thereof and abutting against a lower face of the lid. A plurality of elastic elements is disposed between the bottom wall of the rocker seat and the supporting seat and provides movement elasticity when the rocker seat swings forward or rearward relative to the supporting seat. The supporting face abuts against the lower face of the lid during swinging movement of the rocker seat.

A resistive motion support mechanism joined to a mounting surface and to a base for providing resistive support to the mounting surface as the mounting surface undergoes one or both of rotational and tilt movement relative to the base, the motion support mechanism comprising: a support bearing connected to the mounting surface and to the base which permits one or both of tilting and rotational motion of the mounting surface relative to the base; a resistance cartridge fixedly connected to the mounting surface such that the resistance cartridge undergoes movement relative to the base and applies a resistive force on the base as the mounting surface undergoes the one or both of rotational and tilt movement. The mounting surface and the resistance cartridge are connected by at least one sensor for measuring one of forces applied by the mounting surface on the resistance cartridge, movement of the mounting surface with respect to the cartridge and/or acceleration of the mounting surface with respect to the cartridge.

A connection assembly for a backrest, of an office or conference chair, includes a backrest structural element, a transverse support element, a transverse bearing by means of which the backrest structural element is rotatably coupled to the transverse support element in a direction perpendicular to a transverse direction, and a connection portion connecting the transverse support element to the backrest structural element, arranged and formed so that the backrest structural element is resiliently movable relative to the transverse support element.

A chair has a seat portion and a leg portion. The seat portion and the leg portion are joined by a structure that allows that seat portion to wobble relative to the leg portion. The structure can including one or more resilient member to create the wobble and one or more motion restrictor member to limit the amount of wobble or prevent wobble.

A seating structure employing a thermoplastic flexor defining the flexibility and stiffness of a seatback is provided. The seating structure may comprise a seat portion for supporting a user, a seatback portion for supporting a user, a frame for supporting the seat portion and the seatback portion, one or more base portions extending at an angle from the seatback portion, and one or more thermoplastic flexors affixed to or within the seatback and base portions of the seating structure. The thermoplastic flexor has certain material characteristics which define and limit the deflection and a rebound of the seatback portion relative to the base portion when under load. The seating structure may further comprise one or more anchors securing the seatback portion, base portion, and thermoplastic flexor to the frame. The seat portion, seatback portion, and base portion may comprise a unibody or multipiece chair shell, and the thermoplastic flexor may be completely enveloped within the shell, or partially disposed behind the shell in a nested mechanical relationship.

Chair, more especially an office chair, comprising a seat plate (34) which is arranged on an undercarriage (12) and a backrest (14) which in the manner of a so called synchronous mechanism permit a synchronous movement of seat plate (34) and backrest (14), characterized in that the seat plate (34) is mounted laterally tiltable and the backrest includes two backrest supports (22, 24) whose lower ends are mounted pivotally independently of each other on the undercarriage (12) and are coupled in movement to the seat plate (34) in such a manner that by rearward pivoting of the support (22, 24) one side of the seat plate (34) is pressed down on the same side and the opposite side thereof is raised.

A reclinable office chair includes a reclination adjustment unit coupled to a bottom base disposed at the bottom of the office chair and having an angle limiting element disposed below and spaced apart from a connecting element abutting against carrying elements. When a user sitting on the office chair tilts the office chair in a predetermined direction, the connecting element and the carrying elements, whose movement is restricted by a rim of the bottom base, are stopped from tilting further as soon as the angle limiting element tilts to an extent to come into contact with the rim, not only allowing the office chair in operation to be tilted within a predetermined safety range in any direction, but also enhancing the anti-slip effect which takes place between the office chair and the floor.

An adjustable chair can support an occupant that sits on a front portion of a seat cushion. When the user leans back, the chair can provide back support without requiring that the user slide rearwardly along the seat cushion, thereby providing back support to minimize, limit, or substantially eliminate lower back fatigue, discomfort, or the like. A back support of the chair can be located at a desired forward/rearward position based on the user's position on the seat. In some settings, the chair can be used by a card dealer who tends to sit on a forward portion of the seat when dealing cards. The back support can be positioned to comfortably support the dealer's back when, for example, the dealer sits generally upright. The chair can also be used by other individuals that frequently sit on the front of the seat cushion.