Abstract: A chair control mechanism for use with a single stage gas spring construction for chair height adjustability includes a main control housing having an upwardly directed opening and an upper control housing having a downwardly directed opening. The two housings are dimensioned and configured to nest with one another and are connected by pivot members. An aperture is provided in the main control housing for receiving an end of a gas spring. A bracket assembly is welded to the main control housing and has two apertures both vertically aligned with the aperture of the main control housing and spaced above the aperture of the main control housing. The apertures of the bracket assembly are dimensioned and configured to engage a tapered end of the gas spring and support the control mechanism thereon with the end of the gas spring recessed well up into the control mechanism.

Abstract: A chair has a seat supported on a base support assembly. The support assembly includes an upper bracket with a transverse tube mounted on the forward end thereof. The seat includes an upper shell having hooks extending downwardly from the underside thereof. The hooks are dimensioned and configured to engage the tube and provide for pivotable movement of the upper shell about the tube.

Abstract: A chair has a control mechanism configured to limit the angle of tilt of the chair back rest relative to the seat. The control mechanism includes a bracket member configured to be supported on a vertical column of a chair base. A rotational member attachable to the chair back rest is supported for rotation on an end of the bracket member. A generally elongated stop member is secured to the tubular member at a position extending inwardly of the end of the bracket member. A slide member extends along the longitudinal axis of the bracket member and has one end provided with at least one downwardly directed inclined edge. The stop member has a free distal end configured to engage the inclined edge and limit rotation of the tubular member. By this arrangement, the chair user can adjust the degree of rearward tilt of the back rest by selected movement of the slide member longitudinally of the bracket member.