Adjustable foam and coil spring mattress combination

Abstract

The invention modulates the air-volume in both mattress-type foam and traditional coil spring cores interactively, obtaining a wide variety of levels of density and indentation force deflection (IFD or spring-back force). Foam core modulation is used to soften or harden the upper surface of the combined two elements to form enhanced-comfort support surfaces. The combinations include multiple chambers of which at least one is filled with self-inflating foam. In most configurations of the present invention, the chambers are completely sealed and are not air communicable with each other. Each chamber is fitted with a valve used to selectively withdraw air from it—but never to pressurize it by adding air forcibly. The combinations of core layers include traditional coil spring cores that may or may not be completely enclosed in their own enclosure. When air is extracted from a self-inflating foam core, its surface softens uniformly, density increases while its IFD value drops. When air is extracted from a layer containing traditional coil springs, however, the surface hardens and the IFD value increases, because the compressed coils want to spring back to their original relaxed position. The invention takes advantage of the unique interactive behavior of self-inflating foam and coil spring constructions to create multiple levels of comfort for one or more users of the same device. It is intended for all types and forms of support apparatuses, such as mattresses, seats and cushions.