Load bearing surface

Abstract

An elastomeric load bearing surface with different load support characteristics in different directions. In one embodiment, the surface includes an elastomeric membrane that is oriented in only a single direction, for example, by compression or stretching. In another embodiment, the surface includes mechanical structures, such as connectors and variations in thickness that vary the load support characteristics in different directions. In another embodiment, a surface is both oriented and includes mechanical structures.

1 . A load bearing surface comprising a molded elastomeric membrane, said membrane being oriented in a first direction, whereby said membrane provides different load bearing characteristics in said first direction than in a second direction.  
   
   
       2 . The surface of  claim 1  wherein said membrane includes an integral edge, said integral edge adapted to permit mounting of said membrane to a support structure.  
   
   
       3 . The surface of  claim 2  wherein said integral edge defines at least one receptacle hole, said receptacle hole adapted to receive a protrusion extending from said support structure.  
   
   
       4 . The surface of  claim 3  wherein said integral edge extends along a first side of said membrane, and a second side of said membrane, said second side opposite said first side, said first and second sides extending perpendicular to said first direction.  
   
   
       5 . The surface of  claim 4  wherein said membrane includes a first section having a first thickness and a second section having a second thickness, said first section extending substantially in said second direction.  
   
   
       6 . The surface of  claim 5  wherein said integral edge has a third thickness, said third thickness being at least 3 times thicker than said first thickness.  
   
   
       7 . The surface of  claim 3  wherein said mechanical structure includes a plurality of channels integrally formed with said membrane, said channels extending in substantially said first direction.  
   
   
       8 . The surface of  claim 1  wherein said membrane defines a plurality of nodes interconnected by a plurality of connectors, said connectors extending in said first direction having different physical characteristics than said connectors extending in said second direction, whereby said membrane is decoupled at least in part by differences in said physical characteristics of said plurality of connectors.  
   
   
       9 . The surface of  claim 1  wherein at least a portion of said membrane includes a crystalline structure having a greater degree of alignment in said first direction than in other directions.  
   
   
       10 . A method for manufacturing a load bearing surface, comprising the steps of: 
 molding an elastomeric membrane;    orienting at least a portion of the elastomeric membrane in only one direction until the crystalline structure of the membrane becomes sufficiently aligned in the one direction to provide the portion of the elastomeric membrane with load bearing characteristics in the one direction that are different from other directions.    
   
   
       11 . The method of  claim 10  wherein said orienting step is further defined as stretching at least a portion of the elastomeric membrane in the one direction to at least approximately three times the original dimension of the portion of the membrane.  
   
   
       12 . The method of  claim 11  wherein the molded membrane is stretched within a period of 15 minutes after it is removed from the mold, while the membrane is still in a heated condition.  
   
   
       13 . The method of  claim 11  wherein the mold membrane is stretched to a sufficient distance that it is plastically deformed.  
   
   
       14 . The method of  claim 11  wherein the membrane is stretched from an original distance to a first distance, then relaxed to a second distance between said original distance and said second distance, and then stretched to a third distance longer than said second distance.  
   
   
       15 . The method of  claim 11  further including the steps of: 
 molding the elastomeric membrane with an integral edge; and    attaching the elastomeric membrane to a support structure by the edge.    
   
   
       16 . The method of  claim 15  wherein the step of stretching the membrane includes pulling the membrane at the integral edge.  
   
   
       17 . The method of  claim 15  wherein the step of attaching the membrane to a support structure includes inserting a plurality of protrusions on the support structure into a plurality of corresponding receptacles defined in the integral edge of the membrane.  
   
   
       18 . The method of  claim 15  wherein the stretched membrane is attached to the support structure before it has recovered to a final length.  
   
   
       19 . The method of  claim 10  wherein said orienting step is further defined as: 
 constraining at least a portion of the elastomeric membrane on all sides except at least one unconstrained side corresponding with the one direction;    compressing the portion of the elastomeric membrane until the material of the portion of the elastomeric membrane flows outwardly along at the unconstrained side in the one direction.    
   
   
       20 . A method for manufacturing a load bearing surface, comprising: 
 molding an elastomeric membrane such that the membrane includes a plurality of nodes interconnected by a plurality of connectors, the connectors extending in a first direction, the connectors having a thickness that is less than the thickness of the nodes;    orienting the elastomeric membrane by stretching the membrane in the first direction to a distance sufficient to plastically deform the membrane and to provide the crystalline structure of the membrane with a greater degree of alignment in the first direction; and    mounting the membrane to a support structure before the membrane has recovered to a final length, the membrane continuing to recover after it is mounted to the support structure, the fully recovered membrane providing a desired about of tension between the support structure and the membrane.    
   
   
       21 . A load bearing surface comprising: 
 a support structure;    a molded elastomeric membrane, at least a portion of said membrane being oriented to have a crystalline structure with a greater alignment in a first direction than in a second direction, said membrane molded to include mechanical structure decoupling said membrane between said first direction and said second direction; and    attachment means between said support structure and said membrane for supporting said membrane in tension on said support structure.    
   
   
       22 . The load bearing surface of  claim 21  wherein said attachment means includes an integral edge molded into said membrane, said integral edge defining a plurality of receptacles, and a plurality of protrusions on said support structure, each of said protrusions being inserted into a corresponding one of said receptacles.  
   
   
       23 . The load bearing surface of  claim 22  wherein said protrusions each include an outer edge, at least a portion of said outer edge being tapered.  
   
   
       24 . The load bearing surface of  claim 23  wherein said outer edge includes first and second sidewalls facing in said second direction, and third and fourth sidewalls facing in said first direction, said first and second sidewalls having a greater degree of taper than said third and fourth sidewalls.  
   
   
       25 . The load bearing surface of  claim 21 , wherein portions of said membrane have a greater degree of orientation than other portions of said membrane, said portions of greater orientation having a greater degree of elasticity than said other portions.  
   
   
       26 . The load bearing surface of  claim 25 , wherein said membrane include a plurality of nodes interconnected by connector segments, said connector segments having a greater degree of orientation than said nodes.  
   
   
       27 . The load bearing surface of  claim 26  wherein said nodes are arranged in a matrix.