Chair comprising a support structure, to which a backrest is hinged, reclinable between an inoperative position and a reclined position, and a spring, which is connected to the backrest and to the support structure and can tensioned in a first direction, following the movement of the backrest, in order to exert an elastic return force to bring the backrest back from the reclined position into the inoperative position. The chair also comprises an adjustment device adapted to adjust the elastic return force exerted by the spring and comprising an actuation system, which is connected to the backrest, can be removably connected to the spring and is configured to tension, following the movement of the backrest, the spring in a second direction, to increase the elastic return force exerted by the spring due to the movement of the backrest from the inoperative position towards the reclined position.

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 a seat support structure, a back support structure, a back tensioning assembly adjustable between low and high tension positions, an actuator assembly adapted to adjust the back tensioning assembly between the low and high tension positions, a control input assembly actuable by rotating the portion of the control input assembly, and a control link assembly operably coupling the control input assembly with the actuator assembly to adjust the back tensioning assembly between the low and high tension positions upon rotation of the portion of the control assembly by a seated user, wherein a number of rotations of the portion of the control input assembly is not limited by the control link.

The present disclosure relates to a chair tray and chassis, chassis forming method and chassis mounting structure of the same. The chair chassis comprises a chassis body that is arranged with a mounting hole thereon for mounting a regulating knob. The edge at the position corresponding to the mounting hole of the chassis body is arranged with a flange. The structural strength and the fatigue strength of the chassis can be enhanced effectively by arranging the flange at the position corresponding to the mounting hole of the chassis, which avoids the occurrence of fracture at the perimeter of the mounting hole of the chassis during use or test and thus enables the thickness of the chassis to be reduced below 3 mm, reducing production material to a very large extent and saving production cost while also ensuring that it can pass the back pad fatigue test in the BIFMA standard.

A seating unit component assembly comprises a support component that includes a first surface adapted to abut a seated user, a second surface opposite the first surface, a first end surface, a second end surface opposite the first end surface, and a pair of side surfaces extending between the first and second end surfaces, and a cover having a plurality of sides that cooperate to form an interior space that receives the support component therein, wherein the cover includes a first portion comprising a non-fabric substantially flexible thermoplastic material covering at least a portion of at least one of the side surfaces of the support component, a second portion comprising a fabric covering at least a portion of the first surface and at least a portion of the first end surface of the support component, and a third portion comprising a substantially rigid overlay covering at least a portion of the second end surface and at least a portion of the second surface.

A seating unit component assembly comprises a support component that includes a first surface adapted to abut a seated user, a second surface opposite the first surface, a first end surface, a second end surface opposite the first end surface, and a pair of side surfaces extending between the first and second end surfaces, and a cover having a plurality of sides that cooperate to form an interior space that receives the support component therein, wherein the cover includes a first portion comprising a non-fabric substantially flexible thermoplastic material covering at least a portion of at least one of the side surfaces of the support component, a second portion comprising a fabric covering at least a portion of the first surface and at least a portion of the first end surface of the support component, and a third portion comprising a substantially rigid overlay covering at least a portion of the second end surface and at least a portion of the second surface.

The present invention discloses a chair tray and chassis, chassis forming method and chassis mounting structure of the same. The main points of its technical solution are that the chair chassis comprises a chassis body that is arranged with a mounting hole thereon for mounting a regulating knob. The edge at the position corresponding to the mounting hole of the chassis body is arranged with a flange. The structural strength and the fatigue strength of the chassis can be enhanced effectively by arranging the flange at the position corresponding to the mounting hole of the chassis, which avoids the occurrence of fracture at the perimeter of the mounting hole of the chassis during use or test and thus enables the thickness of the chassis to be reduced below 3 mm, reducing production material to a very large extent and saving production cost while also ensuring that it can pass the back pad fatigue test in the BIFMA standard. Additionally, the fact that the flange surrounds the mounting hole can increase the structural strength and the fatigue strength at the perimeter of the mounting hole of the chassis more all around with a better effect.

A body support structure including a pair of laterally spaced apart supporting arms defining a gap therebetween, wherein each of the supporting arms includes an upper support having an upwardly extending upright and a forwardly extending seat support defining a seat part, and a lower support having an upwardly extending upright spaced apart from the upright of the upper support in a vertical plane. The uprights of the upper and lower supports define a backrest part. A pair of armrests each includes an upwardly extending portion connected to a respective one of the forwardly extending seat supports and a forwardly extending portion pivotally connected to the backrest part. A cross brace extends between and is coupled to the supporting arms proximate the pivotal connection. A flexible membrane extends between and is coupled to the supporting arms.

A chair includes a base structure, a seat carried by the base structure, and a backrest movable relative to the seat between a rest position and a rearward inclined position, wherein the backrest has a connecting portion having a front surface and a rear surface, and wherein the seat has first and second guide surfaces which guide, respectively, the front surface and the rear surface of the connecting portion of the backrest.

A lounge chair having a seat shell that defines a chair back and a seat is pivotally movable about a stationary base. The stationary base includes a concave support surface having a shape that generally corresponds with a convex outer surface of the seat shell. A swivel disc is positioned between the seat shell and the base to allow the seat shell to pivot about the stationary base. The interaction between a pivot post formed on the base and a pivot limiting guide formed in the seat shell defines the range of movement for the seat shell. A bias member connects the seat shell to the seat base and creates a bias force to urge the seat shell into an upright seating position. The base includes a series of glide buttons that support the swivel disc to allow the seat shell to pivot relative to the stationary base.