Abstract: The invention is related to a hub construction for a rotatable chair, which automatically returns to the initial position when the chair is relieved. The hub construction comprises a vertical shaft (1) fastened to the lower side of the seat of the chair and a hub (2) on the leg portion of the chair, to which hub (2) the lower portion of the shaft (1) is rotatably fastened. The return movement is achieved by means of a cam surface (5) acting in the axial direction and located on the end of a spring loaded sleeve (6) enclosing the shaft (1), which cam surface (5) is arranged to cooperate with a radially directed guide pin (4). The invention is characterized in that the guide pin (4) is fastened to the lower portion of the shaft (3) and that the spring loaded sleeve (6) is mounted torsionally rigidly on the hub (2).