Locking mechanism

Abstract

A seating system includes seat and back internal support frames disposed within respective foam-filled seat and back cushions which each have an outer fabric cover. The back assembly is provided with a pair of quick-release clip locks, while the seat assembly includes a plurality of support hooks in combination with mounting brackets and locking mechanism to facilitate quick mounting and removal of the seat from a support frame such as a wheelchair base. The seat and back assemblies are coupled together in a pivoting manner by means of a handle assembly which alows the seat to be compactly folded and easily carried when removed from a support base. The back inner support frame includes upper and lower support subassemblies pivotally coupled by means of a hinge joint which allows for extension of the lumbar region when the upper support subassembly is moved rearwardly to a reclined position. The seat and back support surfaces are contoured for user comfort and support while a lower, aft portion of the back cushion is provided with a plurality of corrugations to facilitate its flexure. The internal support frame includes telescoping members to allow the internal frame to fit a range of user sizes while the hinge joint in the lower portion of the back assembly may: (1) be locked in a fixed orientation; (2) incorporate forward and aft stops to limit pivoting displacement of the upper back; or (3) have a selected neutral position to which the upper back is biased.