US Patent 7594700 Contoured seating structure

A chair includes a control housing, a seat and a back support including an upwardly extending upright portion and a link portion extending forwardly from a lower portion of the upright portion. The link portion is pivotally connected to the control housing about a first pivot axis. The seat is connected to the link portion and is pivotable relative thereto. A linkage is coupled to the seat and is pivotally connected to the control housing at a second pivot axis positioned rearwardly and downwardly from the first pivot axis.