Pressure distribution pad assembly for wheelchairs

Claim 1

A pressure distribution pad assembly for a wheelchair comprising, in combination: a. first and second outside pads of resilient foam material of a given density; b. a center pad of resilient foam material of density greater than said given density, sandwiched between said outside pads, the front edges of the pads being straight and in which the rear edges are convexly curved in the plane of the pads, said center pad having three cut-outs defining openings therethrough positioned on the vertices of an imaginary isosceles triangle in the plane of the center pad, the openings at the vertices of the triangle defining the base angles being equal in area, the opening at the vertex opposite the base side being of less area than either one of the other openings, and, wherein the base of said isosceles triangle is parallel to the front edge of the pad and spaced therefrom a given distance, greater than one half the length of the pad the opening at the vertex of the triangle opposite the base side being between the base side of the triangle and rear edge of the pad, the vertex angle being between 30° and 120°; c. filler foam material in said openings of density less than said given density, said filler foam material comprising a total volume between one eighth and one half the volume of said center pad; and d. a cover enclosing the pads, said cover having manually operable closure means permitting removal of the pads therefrom so that said cover can be cleaned and the pads reinserted, the seat cushion being symmetrical with respect to its top and bottom surfaces so that it functions to distribute the pressure exerted on a person seated on either the top or bottom surface with the convex rear portion adjacent the rear of the person, said pressure distribution resulting from said cut-out openings containing said filler foam material in the center pad.