Adjustable foam mattress

Abstract

The invention modulates the air volume in foam cores of cushioning support devices and any other support apparatus using foam or similar materials. The foam core can be incrementally modulated to realize an infinite number of comfort levels as to softness and support firmness. The core consists of self-inflating open-cell flexible polyurethane foam and is completely sealed within an enclosure fitted over it, with one or more valves installed in the side walls which communicate with the outside air. Through the valves air is selectively withdrawn from the foam core, allowing the foam's density to increase. The invention uses relatively inexpensive foam, but through air volume modulation achieves a tactile feel of supreme softness for the user, without giving up the necessary firmness to support the body, as happens with very soft foam (bottoming-out or hammock-effect). When air is extracted from a self-inflating foam core, the surface of the core will soften uniformly while maintaining its support firmness. Contrary to this, when pressure is exerted on, for example, traditional coil spring core mattresses, their surface will harden. Integral part of the invention is a device using balanced springs in valve assemblies to avoid compression set, an irreversibly solid state of totally air-depleted foam.

1 . A cushioning apparatus adapted to cushion objects placed on either surface of said apparatus, said apparatus including one or more pieces of open cell self-inflating flexible polyurethane foam to form a foam core, said foam core being covered by one or more hermetically sealed envelopes forming one or more autonomous airtight chambers, and one or more valves installed in said chamber walls and removably connected to a vacuum pump by way of a hose, said vacuum pump being operated to remove some air uniformly from within said open cells to change the softness and support ratio within the foam core, whereby the principal characteristics of the open cell, self-inflating polyurethane foam are controlled and modulated.  
   
   
       2 . The apparatus for  claim 1  in which said operating said pump increases the cellular density of said foam core.  
   
   
       3 . The apparatus of  claim 1  wherein said foam core has an IFD value within a range of 22 to 50 in an original factory preset configuration and a progressively decreasing value when some air is removed from said core.  
   
   
       4 . The apparatus of  claim 1  wherein said foam core has a density within a range of 1.2 to 2.5 pounds per cubic foot in an original, factory preset configuration, and a progressively increasing density when some air is removed from said foam core, without adding weight to the overall apparatus.  
   
   
       5 . The apparatus of  claim 4  wherein said foam core exhibits a diminishing density and an increasing IFD value when allowed to self-inflate from a collapsed state.  
   
   
       6 . The apparatus of  claim 1  further including a pressure-balanced closure spring located in said valve.  
   
   
       7 . The apparatus of  claim 6  including a means for opening and closing said valve and said closure spring.  
   
   
       8 . The apparatus of  claim 7  including means for opening said valve by a hose, which is removably attached to said valve.  
   
   
       9 . The apparatus of  claim 6  including a closure force of said spring which equals the re-inflating force of said foam core when said foam core is in a partially inflated state so that no more air can enter said foam core.  
   
   
       10 . The apparatus of  claim 6  in which said spring has a pressure-balanced closure force within a range of 2 lb. to 6.0 lb.  
   
   
       11 . The apparatus of  claim 1  further including an air-permeable distancing element contiguous with said foam material in said chamber for distancing said valve in said chamber from any adjacent materials that may obstruct airflow.  
   
   
       12 . The apparatus of  claim 1  whereby a partially deflated foam core contained within an autonomous airtight chamber, having a closed valve, recovers slowly when a weight placed upon said chamber is removed, thereby exhibiting the principal characteristics of visco-elastic foam.  
   
   
       13 . The apparatus of  claim 12  whereby further deflation of a partially deflated foam core contained within an autonomous airtight chamber, having a closed valve, exhibits no upward recovery thereby exhibiting less upward pressure than visco-elastic foam.  
   
   
       14 . The apparatus of  claim 1 , wherein said self-inflating foam core adjusts to pressure points only locally without creating a hammock effect.  
   
   
       15 . A cushioning apparatus adapted to cushion objects placed on either a top or bottom surface of said apparatus, said apparatus comprising: 
 at least one piece of open cell, self-inflating foam that forms a foam core, said foam core being enclosed within a flexible airtight chamber;    at least one valve installed through said chamber in communication with said foam core; and    a vacuum pump connected to said valve and being operated to remove some air uniformly from within said open foam cells and through said valve to change the softness and support ratio within said foam core, whereby operating said vacuum pump controls and modulates the principal characteristics of said foam core, each foam core having a respective factory preset density and IFD rating and further combined into a respective autonomous airtight chamber within said apparatus.