Seat support column

Claim 1

Apparatus for adjustably and rotatably mounting the seat of a chair or stool to a base comprising: (a) a support cylinder, a height adjusting gas spring, and a generally tubular casing secured to the underside of said seat; (b) said support cylinder including an annular mounting plate adjacent the lower end thereof and a generally open top; (c) said height adjusting gas spring including a gas cartridge having a diameter less than the diameter of said support cylinder with a piston rod protruding from one end thereof, a cartridge pin adjacent the other end of said gas cartridge, said gas cartridge being vertically reciprocal along said piston rod responsive to depression of said cartridge pin; (d) the free end of said piston rod being attached to said annular mounting plate in such a manner as to be rotatable thereon, but radially and axially fixed with respect thereto, whereby said height adjusting cartridge is substantially disposed within the support cylinder in parallel spaced relation to the cylindrical wall thereof; (e) the longitudinal axes of said support cylinder, said piston rod, and said gas cartridge being colinear with respect to each other and remain substantially vertically erect at all times; (f) said tubular casing having an upper section and a generally cylindrical lower section, the lower section having a diameter greater than the diameter of said gas cartridge and less than the diameter of said support cylinder, a collar means for substantially enclosing the upper end of said lower section, the lower end of said casing being generally open, and said cartridge providing substantially the entire support for said casing; (g) an activating pin extending through the upper end of said casing and said activating pin engages said cartridge pin through an opening in an upper wall of said cartridge; said activating pin being radially or laterally movable with respect to said cartridge pin for selective activation thereof; (h) the longitudinal axis of said casing being tiltable or laterally shiftable with respect to the longitudinal axes of said support cylinder, piston rod, and height adjusting cartridge responsive to non-axial or side loads on said seat member, whereby the damaging or objectionable effects of such side loads are minimized.