Foam seat and back cushions

Claim 1

A seat cushion comprising cellular elastic material, said material being divided into segments having different moduli of elasticity, the modulus of elasticity of each segment being inversely proportional to the pressure exerted on such segment by the anatomical portion to a person seated against said cushion to more uniformly distribute the supportive forces exerted by the cushion over a larger area of said anatomical portions, said segments comprising pre-formed blocks of said cellular elastic material assembled together to form said cushion, a first, substantially horseshoe-shaped segment forming both side edges and the rear edge of said seat cushion; a second, substantially horseshoe-shaped segment disposed within said first segment, said second segment being open at the front edge of said cushion; a third, substantially wedge-shaped segment disposed within said second segment and extending rearwardly from said front edge of said cushion, said third segment tapering from said front edge toward said rear edge of said cushion and extending more than halfway from said front edge toward said rear edge of said cushion; and a fourth, substantially elliptical prismatic segment having its major axis extending substantially across the width of said cushion, said fourth segment lying within said second segment and surrounding the rear end of said third segment, said third segment extending into the indentation defined by the forward wall of said fourth segment, said first and third segments being relatively firm and said second and fourth segments being relatively soft.