Flexible midsole for shoe and shoe incorporating same

Abstract

A shoe includes an upper, an outsole, and a midsole. The midsole can be constructed with a plurality of geometric protrusions formed in the upper surface of the midsole, the lower surface of the midsole, or both surfaces. In one embodiment, the protrusions can be substantially triangular in cross-section. A plurality of grooves can separate the protrusions from one another including a first set grooves extending in a longitudinal direction, a second set of grooves extending in a lateral direction, a third set of grooves extending at a positive angle relative to longitudinal direction and a fourth set of grooves extending at a negative angle relative to the longitudinal direction.

What is claimed is: 
     
         1 . A midsole for use in a shoe, the midsole comprising:
 a body having an upper and a lower surface;   a plurality of triangular protrusions formed in at least one of the upper surface and the lower surface.   
     
     
         2 . The midsole of  claim 1 , wherein the plurality of triangular protrusions are separated from each other by a plurality of grooves. 
     
     
         3 . The midsole of  claim 2 , wherein the plurality of grooves include a first set of grooves extending in a first direction extending generally longitudinally from a heel portion through a toe portion. 
     
     
         4 . The midsole of  claim 3 , wherein the plurality of grooves includes a second set of grooves extending in a second direction substantially orthogonal to the first direction. 
     
     
         5 . The midsole of  claim 4 , wherein the plurality of grooves includes at least a third set of grooves extending in a third direction that is non-orthogonal to the first direction. 
     
     
         6 . The midsole of  claim 4 , wherein the third direction is at an angle of approximately 45° to the first direction. 
     
     
         7 . The midsole of  claim 2 , wherein the plurality of grooves include a first set of grooves extending at a defined angle relative to a longitudinal direction that extends generally from a heel portion through a toe portion. 
     
     
         8 . The midsole of  claim 7 , wherein the plurality of grooves includes a second set of grooves extending in a direction that is substantially orthogonal to the first set of grooves. 
     
     
         9 . The midsole of  claim 8 , wherein the defined angle is approximately 45°. 
     
     
         10 . The midsole of  claim 2 , wherein the grooves extend a depth of approximately 3.5 millimeters into the body. 
     
     
         11 . The midsole of  claim 2 , wherein the body is formed of a material comprising at least one of ethyl vinyl acetate and polyurethane. 
     
     
         12 . A shoe, comprising:
 an upper;   an outsole; and   a midsole comprising:
 a body having an upper and a lower surface, 
 a plurality of triangular protrusions formed in at least one of the upper surface and the lower surface. 
   
     
     
         13 . The shoe of  claim 12 , wherein the plurality of triangular protrusions are separated from each other by a plurality of grooves. 
     
     
         14 . The shoe of  claim 13 , wherein the plurality of grooves include a first set of grooves extending in a first direction extending generally longitudinally from a heel portion through a toe portion. 
     
     
         15 . The shoe of  claim 14 , wherein the plurality of grooves includes a second set of grooves extending in a second direction substantially orthogonal to the first direction. 
     
     
         16 . The shoe of  claim 15 , wherein the plurality of grooves includes at least a third set of grooves extending in a third direction that is non-orthogonal to the first direction. 
     
     
         17 . The shoe of  claim 15 , wherein the third direction is at an angle of approximately 45° to the first direction. 
     
     
         18 . The shoe of  claim 13 , wherein the plurality of grooves include a first set of grooves extending at a defined angle relative to a longitudinal direction that extends generally from a heel portion through a toe portion. 
     
     
         19 . The midsole of  claim 18 , wherein the plurality of grooves includes a second set of grooves extending in a direction that is substantially orthogonal to the first set of grooves. 
     
     
         20 . A shoe, comprising:
 an upper;   an outsole; and   a midsole comprising:
 a body having an upper and a lower surface, 
 a plurality of triangular protrusions formed in at least one of the upper surface and the lower surface, the plurality of triangular protrusions are separated from each other by a plurality of grooves, the plurality of grooves including:
 a first set of grooves extending in a first direction extending generally longitudinally from a heel portion through a toe portion, 
 a second set of grooves extending in a second direction substantially orthogonal to the first direction, 
 a third set of grooves extending in a third direction that is oriented at an angle of approximately 45° to the first direction; and 
 a fourth set of grooves extending in a fourth direction that is substantially orthogonal to the third direction.