Patent ID: 8091841

Claim:
A support assembly, the assembly comprising: a first elongated member having a length dimension parallel to a substantially vertical extension axis; a second elongated member supported by the first member for sliding motion along the extension axis between at least an extended position and a retracted position; a spring that generates a variable spring force that depends at least in part on the degree of spring loading, the spring having first and second ends, wherein the first end of the spring is supported by the second elongated member; an equalizer assembly including a strand having first and second ends, the first end linked to the second end of the spring and a second end linked to the first member, the force equalizer assembly and spring applying a force between the first and second members tending to drive the elongated members into the extended position wherein the applied force is substantially constant irrespective of the position of the second elongated member with respect to the first elongated member; a preloader supporting at least a portion of the strand, the preloader applying a preload force via the strand to the spring when the second elongated member is in a fully extended position; and an adjuster for adjusting the preload force applied by the preloader.