Modular shoe construction

Abstract

A modular footwear construction includes an upper with a removable outsole. The upper and the outsole both include bottoms having tread surfaces. A removable footbed fits inside the upper, and includes both a cushioning midsole and a structural plate. The outsole is removably secured to the upper without adhesives. In one embodiment, the midsole and the plate each have structure that enables a mechanical interlock therebetween. In another embodiment, a heel strap extends from the outsole and fits over a protrusion on the upper to removably secure the outsole to the upper.

1 . A modular footwear construction comprising:
 an upper having a bottom, said bottom having a tread surface;   a removable outsole having a bottom, said bottom of said outsole extending underneath said bottom of said upper, said bottom of said outsole including a tread surface; and   a removable footbed inside said upper, said removable footbed including a midsole and a plate, said midsole and said plate each including structure to form a mechanical interlock between said midsole and said plate.   
     
     
         2 . The modular footwear construction of  claim 1  wherein one of said midsole and said plate includes a protrusion and the other one of said midsole and said plate includes a cutout sized to receive said protrusion, said protrusion inserted in said cutout to mechanically interlock said midsole and said plate. 
     
     
         3 . The modular footwear construction of  claim 2  wherein each said protrusion is undercut, and wherein each cutout is defined by an angular cut wall that interfits with said undercut of said protrusion. 
     
     
         4 . The modular footwear construction of  claim 3  wherein said one of said midsole and said plate includes a heel portion and a forefoot portion, and wherein said one of said midsole and said plate includes a plurality of said protrusions, at least one of said protrusions located in said heel portion and at least one of said protrusions located in said forefoot portion. 
     
     
         5 . The modular footwear construction of  claim 4  wherein said midsole is formed from a cushioning material and wherein said plate is formed from a rigid or semi-rigid material. 
     
     
         6 . The modular footwear construction of  claim 5  wherein said midsole is formed from EVA and wherein said plate is formed from one of TPU, TPR and PVC. 
     
     
         7 . The modular footwear construction of  claim 6  including a heel strap for removably connecting said outsole and said upper, said heel strap having an attached position in which a portion of said heel strap interfits with a portion of said upper and an unattached position in which said outsole can be separated from said upper. 
     
     
         8 . A modular footwear construction comprising:
 an upper having a bottom, said bottom including a tread surface;   an outsole covering at least a portion of said upper, said outsole including a tread surface;   attachment means for removably attaching said upper to said outsole, said attachment means having an attached position wherein said upper is secured to said outsole and an unattached position wherein said upper is unattached from said outsole, such that said outsole can be manually removed from said upper to expose said bottom of said upper; and   a footbed positioned inside said upper.   
     
     
         9 . The modular footwear construction of  claim 8  wherein said attachment means includes a heel strap extending from one of said outsole and said upper and a connector extending from the other of said outsole and said upper, said heel strap fastened to said connector when said attachment means is in said attachment position, said heel strap not fastened to said connector when said attachment means is in said unattached position. 
     
     
         10 . The modular footwear construction of  claim 9  wherein said heel strap includes a first end connected to said outsole and a second end defining a hole, said connector comprising a protrusion extending from said upper, said protrusion extending through said hole when said attachment means is in said attached position. 
     
     
         11 . The modular footwear construction of  claim 10  wherein said upper and said outsole each include a heel portion, said first end of said heel strap connected to said heel portion of said outsole, said protrusion extending from said heel portion of said upper. 
     
     
         12 . The modular footwear construction of  claim 11  wherein said upper includes a forefoot portion and a toe portion, and said outsole includes a forefoot strap extending over said forefoot portion and a toe cap extending over said toe portion. 
     
     
         13 . The modular footwear construction of  claim 12  wherein said removable footbed includes a cushioned midsole and a structural plate, one of said midsole and said plate including a plurality of protrusions and the other of said midsole and said plate including a plurality of holes aligned with said protrusion, said protrusions extending into said holes to mechanically interlock said midsole and said plate. 
     
     
         14 . A modular footwear construction comprising:
 an upper having sides and a bottom;   an outsole including a bottom and a sidewall extending upwardly from said bottom, said bottom and said sidewall of said outsole cooperating to enclose at least a portion of said upper;   an attachment mechanism removably attaching said outsole and said upper, said attachment mechanism having a first connector attached to said outsole and a second connector attached to said upper, said first and second connectors interfitting with each other to secure said outsole to said upper, said first and second connectors capable of being manually separated to allow said outsole to be removed from said upper to expose said bottom of said upper; and   a removable footbed within said upper, said footbed including a cushioned midsole and a structural plate, said midsole and said plate including structure to mechanically interlock said midsole and said plate.   
     
     
         15 . The modular footwear construction of  claim 14  wherein said bottom of said upper includes a first tread surface and wherein said bottom of said outsole includes a second tread surface. 
     
     
         16 . The modular footwear construction of  claim 14  wherein said footwear construction includes a heel region, and wherein said first connector is a heel strap extending from said outsole in said heel region, wherein said second connector is a protrusion extending from said upper in said heel region. 
     
     
         17 . The modular footwear construction of  claim 16  wherein said outsole is formed from a first material, and wherein said upper and said heel strap are formed from a second material different from said first material. 
     
     
         18 . The modular footwear construction of  claim 14  wherein one of said midsole and said plate includes a plurality of protrusions and the other of said midsole and said plate includes a plurality of holes aligned with said protrusions, said protrusions extending into said holes to interlock said midsole and said plate. 
     
     
         19 . The modular footwear construction of  claim 14  wherein said upper includes a forefoot portion, said attachment mechanism including a forefoot strap attached to said outsole and extending over said forefoot portion of said upper. 
     
     
         20 . The modular footwear construction of  claim 19  wherein said upper includes a toe portion, said outsole including a toe cap extending over said toe portion of said upper.