Patent attributes
A table or desk assembly (20) includes a base having a pair of legs (24), a worksurface (22) supported by and between the pair of legs, and a rapid, counterbalanced height adjustment mechanism interposed between the legs and the worksurface for providing adjustment in the elevation of the worksurface. The height adjustment mechanism includes a pair of high lead rotatable threaded rods (32) engaged with a mating stationary threaded member (33) associated with each leg. A handle (36) is engageable with one of the threaded rods for imparting rotation to the threaded rod, and a synchronizing arrangement, such as a sprocket (38) and chain system (40), is interconnected with the other of the threaded rods for rotating the threaded rods together. A lift assist or counterbalancing mechanism applies an upward bias, such as to the worksurface, to counteract the weight of the worksurface and any loads supported by the worksurface. The counterbalancing mechanism may be in the form of a cylinder assembly (54) having a biased retractable and extendible member, which is interconnected with each of the threaded rods via a cable (66) and pulley (68) arrangement. Alternatively, the lift assist or counterbalancing mechanism may be in the form of constant force spring arrangements (76), each of which has an extendible and retractable member. A retainer arrangement (90) is interposed between the crank or handle member (36) and the worksurface, for preventing inadvertent rotation of the threaded rod and thereby maintaining the elevation of the worksurface.