HYDRAULIC CHAIR HEIGHT ADJUSTMENT MECHANISM

摘要

An adjustement mechanism (16) for adjusting the height of a chair seat (10), table top or the relative position of other items includes an outer support tube (30) and a telescoping, column tube subassembly (32). The column tube subassembly (32) includes an inner support tube (46), a cylinder (62) and a piston (118) and piston rod subassembly (64). The piston rod is connected to the piston at one end and to the outer support tube at the other end. An elastomeric sleeve (68) surrounds the cylinder. A valve (152) controls flow of hydraulic fluid from the interior of the cylinder to and from an expandable chamber defined by the elastomeric sleeve. The piston snap fits onto the piston rod and allows rotation of the column tube subassembly with respect to the outer support tube. A shock-absorbing element (220) is disposed in the cylinder.