Patent ID: 7797776
Filing Date: 2010-09-21
Classification: A61G,Y10S

Abstract:
1. A fluidized bed for supporting a body, comprising a fluid-impervious peripheral wall, a fluid-porous membrane top covering, a fluid-porous floor defining a unit volume, a quantity of glass bead support media confined within the unit volume, a diffuser, located beneath the floor for supplying air through the floor to fluidize the support media, comprising a laminate having a porous membrane top and a porous membrane bottom spaced by a fluid-impervious boundary wall and a plurality of interior walls extending from the top to the bottom to create discrete cells, each cell having a quantity of cell media confined within it; and an air supply for supplying pressure air into all cells of the diffuser and through the porous membrane top into the unit interior volume to fluidize the support media, whereby the amount of fluid flow through any specific cell will be affected by the depth of support media above that cell relative to the depth of support media above other cells, such that, in a first area where support media level is low relative to other areas, fluid flow through the first area cells below will increase and cause cell media therein to coalesce at the membrane top to function as a valve and restrict air flow through the top into the support media above, which will decrease fluidization of support media in the first area, and raise fluid pressure in the diffuser, while in a second area where support media level is higher relative to the first area, increased fluid flow through the second area cells below caused by the pressure increase will increase fluid flow through the cells into the support media above to increase fluidization of the media in the second area, and the resultant pressure differential throughout the support media will cause the support media to self-level to equalize fluid pressure throughout the support media.