Abstract: A chair with user responsive reclinable back-support connected to a seat member by a set of elastically deformable bracket members. A pivot axis defined by an imaginary line connecting the respective center-of-curvature of the bracket members is positionable in substantial correspondence with the chair occupant's hip joint and is selectively displaceable under occupant loading for reclining the back-support.

Abstract: A tilt back chair provides for selective independent and concurrent movement of a chair back with respect to a chair seat. The seat is mounted to a spring biased bracket for pivotal movement about a seat tilt axis. The back is connected to a pair of pivot brackets projecting upwardly from the seat to provide for pivotal movement about a back tilt axis located above the seat and rearwardly of the seat tilt axis. When the seat is in a neutral seating position it can tilt downwardly at its forward edge about the seat tilt axis. The back is biased for displacement with the forward tilt of the seat and is tiltable rearwardly independently of the seat. The seat can also be locked in a fixed position.

Abstract: A chair having a backrest with an adjustable contour includes a slidable lumbar member for selectively changing the location of the contour in correspondence with the anatomy of the chair occupant. The lumbar member is displaceable within a travel slot. A handlebar member is operable by a seated chair occupant for releasably locking the lumbar member at selected heighth positions.

Abstract: A tilt back chair provides for selective independent and concurrent movement of a chair back with respect to a chair seat. The seat is mounted to a spring biased bracket for pivotal movement about a seat tilt axis. The back is connected to a pair of pivot brackets projecting upwardly from the seat to provide for pivotal movement about a back tilt axis located above the seat and rearwardly of the seat tilt axis. When the seat is in a neutral seating position it can tilt downwardly at its forward edge about the seat tilt axis. The back is biased for displacement with the forward tilt of the seat and is tiltable rearwardly independently of the seat. The seat can also be locked in a fixed position.

Abstract: A chair includes a base, a member attached to the base and a seat support pivotable with respect to the member along a generally horizontal axis. The pivoting axis is disposed in parallel with and adjacent to a front edge of the seat. A backrest is hingedly connected to the seat. The seat has extreme forward and back tilt positions which may be selected in accordance with the task that is to be performed.