Abstract: A swivel chair of the type comprising a seat which is supported at an elevated position above a base for swiveling motion relative to the base, and which has a foot support disposed between the base and seat for aiding a user of the chair to ascend to the elevated seat, is provided with clamping elements that are responsive to foot pressure applied to the foot support for preventing swiveling motion of the seat relative to the base when such foot pressure in excess of a predetermined amount is applied. The clamping elements preferably comprise an inclined surface on a bracket that pivotally supports the foot support, and a wedge-shaped element that is disposed between the inclined surface and the pillar of the swivel chair for axial displacement in response to pivotal motion of the foot support resulting from the application of foot pressure thereto.

Abstract: An improved actuator button apparatus is disclosed for use in adjustable chairs. The manually actuable button is pressed through an aperture in the chair frame and then moved along a pivoted lever until the button reaches a retention position. Movement of the lever activates or deactivates a chair positioning linkage within the housing.

Abstract: An improved inclinable chair structure is disclosed in which a laterally movable lever (6), mounted on the seat frame (4) for easy access from the front, moves along a laterally disposed cam surface (2, 2a, 2b) which is rigidly secured to the chair base (1).