Footwear having a filled flex-frame midsole

Abstract

An article of footwear may include a midsole having a flex-frame defining a plurality of cells. Some or all of the cells may be substantially filled with a foam material. The flex-frame may be made of a solid material having a greater stiffness than the foam material. The flex-frame may be unitary in construction.

What is claimed is: 
     
         1 . An article of footwear comprising:
 an upper; and   a sole portion coupled to the upper and including an outsole and a midsole;   the midsole including a resiliently-flexible kinematic frame having a plurality of cells, and a foam at least partially surrounding the frame;   wherein the frame comprises a solid material having a greater stiffness than the foam.   
     
     
         2 . The article of footwear of  claim 1 , wherein the solid material of the frame comprises nylon. 
     
     
         3 . The article of footwear of  claim 1 , wherein the foam comprises ethylene-vinyl acetate. 
     
     
         4 . The article of footwear of  claim 1 , wherein the foam substantially fills an interior of one or more of the cells. 
     
     
         5 . The article of footwear of  claim 1 , wherein the frame comprises at least one continuous member running along a length of the sole and defining a respective perimeter portion of each of the cells. 
     
     
         6 . The article of footwear of  claim 5 , wherein the at least one continuous member forms a respective lower portion of each of the cells. 
     
     
         7 . The article of footwear of  claim 5 , wherein the at least one continuous member comprises an upper continuous member and a lower continuous member, and the plurality of cells are formed between the upper and lower continuous members. 
     
     
         8 . A sole for an article of footwear, the sole comprising:
 a midsole including a plurality of cells each defining an internal volume and mechanically coupled to form a unitary resilient frame; and   a compressible foam surrounding the plurality of cells and filling the internal volume of at least one of the cells;   wherein the resilient frame has a higher stiffness than the foam.   
     
     
         9 . The sole of  claim 8 , wherein the frame has sufficient stiffness to support an expected user without collapsing. 
     
     
         10 . The sole of  claim 8 , wherein the frame comprises a thermoplastic material. 
     
     
         11 . The sole of  claim 8 , wherein the unitary frame is a single, molded piece. 
     
     
         12 . The sole of  claim 8 , wherein the frame comprises at least one lengthwise continuous member joining the plurality of cells. 
     
     
         13 . The sole of  claim 8 , wherein adjacent cells are spaced apart along a length of the sole, such that a respective gap is formed between adjacent cells. 
     
     
         14 . The sole of  claim 8 , wherein the plurality of cells are arranged in a single layer of side-by-side cells. 
     
     
         15 . An article of footwear comprising:
 an upper; and   a sole coupled to the upper, the sole including a plurality of molded spring-like cells integrated into a single layer to form a flexibly resilient kinematic frame, each cell extending at least partially across a width of the sole;   wherein an interior volume of each cell is substantially filled with a compressible foam material.   
     
     
         16 . The article of footwear of  claim 15 , wherein a cross section of each cell taken parallel to a long axis of the sole is generally polygonal. 
     
     
         17 . The article of footwear of  claim 15 , wherein the layer of cells are connected by at least one common lengthwise member. 
     
     
         18 . The article of footwear of  claim 17 , wherein the at least one common lengthwise member comprises an upper member and a lower member, and the cells are formed between the upper and lower members. 
     
     
         19 . The article of footwear of  claim 15 , wherein each of the cells is angled forward toward a toe of the footwear, such that an upper portion of each cell is farther forward than a lower portion of the same cell. 
     
     
         20 . The article of footwear of  claim 15 , wherein a lower portion of the frame comprises an outsole.