Buoyancy devices using conformal cavities

Abstract

The invention employs the principle that the force of buoyancy received by a body immersed in a liquid is determined by the density of the liquid and the extent or depth of immersion in the liquid and is unrelated to the displacement of the liquid by the body, thereby reducing the total size and weight of devices providing buoyant support. Buoyant support is provided to bodies in a manner that permits devices to be made for the measurement of both small and large weights and for support of the human body for the purpose of relieving the pressure induced trauma and skin abrasion otherwise incurred by bedridden patients, such as burn victims and those requiring extended or continual bed rest. A tub-like cavity that closely conforms in size and shape to the part of the body to be immersed is made to contain and float a human body on a volume of liquid that equals only a fraction of the body's weight. Buoyancy may thus be increased by increasing the density of the liquid without undue expense and it also becomes both practical and convenient to add soothing emollients, as well as more specifically prescribed topical medications, to the supporting liquid for automatic distribution and application. Restricted range of movement and the minimal presence of liquid permits an immersed patient to be left relatively unattended without the usual drowning hazard.

What is claimed as new and what is desired to secure by Letters Patent of the United States is:  
     
         1 . A combination comprising a structure containing a liquid and a body portion immersed in said liquid, said structure defining a cavity having walls formed to generally conform to the horizontal shaping of said immersed portion of said body and formed slightly larger to minimize the horizontal space between said walls and portion of said body when said portion is immersed in said cavity, so that a volume of liquid that occupies said space and immerses said portion of said body is minimized, thereby minimizing the total size and weight of said combination.  
     
     
         2 . The combination as defined in  claim 1 , wherein said cavity walls and said body include vertically extending portions with substantially uniform horizontal dimensions to permit a substantially uniform spacing therebetween that is maintained at differing levels of body immersion.  
     
     
         3 . The combination as defined in  claim 2  wherein said body is adapted to receive additional weight and reacts to an addition of weight by a downward deflection and increase in immersion, said combination including measuring means to provide an indication of the amount of said added weight.  
     
     
         4 . The combination as defined in  claim 1  wherein said body is adapted to receive additional weight and wherein weight added to said body is measured without appreciable downward deflection of said body by the difference between the level of liquid required to float said body with said weight added and the level required to float said body without said weight.  
     
     
         5 . The combination as defined in  claim 1 , wherein said body includes walls, said cavity walls and said body walls being formed as non-vertical walls, said body descending into said cavity causing said walls of said body to move closer to said walls of said cavity, and increase the rate of immersion relative to descent of said body, thereby increasing the rate of increase in buoyant force, relative to descent of said body.  
     
     
         6 . The combination as defined in  claim 1 , wherein said body to which said cavity walls generally conform, is preexistent.  
     
     
         7 . The combination as defined in  claim 6  wherein the said body is a human body.  
     
     
         8 . The combination as defined in  claim 7 , wherein said liquid is a solution containing substances that increase its density and thereby increase its buoyant force.  
     
     
         9 . The combination as defined in  claim 7 , wherein the said solution is made to contain soothing emollients to benefit the skin.  
     
     
         10 . The combination of  claim 1 , wherein said body is a floating vessel.  
     
     
         11 . The combination as defined in  claim 1  wherein said cavity walls conform generally to all surfaces of said immersed portion of said body.