Sole Structure

Abstract

A sole structure includes an upper midsole made of an elastic material and a lower midsole made of an elastic material and bonded from below to the upper midsole. The upper midsole has first protrusions protruding toward the lower midsole, and the tip ends of the first protrusions are in contact with the lower midsole such that the tip ends of the first protrusions can move with respect to the lower midsole.

What is claimed is: 
     
         1 . A sole structure for a shoe, comprising:
 an upper midsole made of an elastic material; and   a lower midsole made of an elastic material and bonded from below to the upper midsole, wherein   at least one of the upper midsole and the lower midsole has a protrusion protruding toward the other midsole, and when a shoe is in an unworn state, a tip end of the protrusion is not in contact with the other midsole or is in contact with the other midsole such that the tip end of the protrusion can move with respect to the other midsole, and   when a foot lands, the tip end of the protrusion is pressed against the other midsole and is thus moved with respect to the other midsole in a direction along a surface of the other midsole.   
     
     
         2 . The sole structure of  claim 1 , wherein
 the protrusion is tapered so that its tip end is thinner than its base end.   
     
     
         3 . The sole structure of  claim 1 , wherein
 a plurality of the protrusions are formed, and the protrusions adjacent to each other in a longitudinal direction are spaced apart from each other in the longitudinal direction.   
     
     
         4 . The sole structure of  claim 1 , wherein
 the protrusion is formed in a region supporting a wearer's heel.   
     
     
         5 . The sole structure of  claim 1 , wherein
 a longitudinal dimension of the protrusion is smaller than a lateral dimension thereof.   
     
     
         6 . A sole structure for a shoe, comprising:
 an upper midsole made of an elastic material; and   a lower midsole made of an elastic material and bonded to, or formed integrally with, a lower surface of the upper midsole, wherein   at least one of the upper midsole and the lower midsole has a protrusion protruding toward the other midsole, the protrusion has a bent or narrowed intended deformation portion formed in its intermediate portion in a direction in which the protrusion protrudes, and a tip end of the protrusion is in close contact with, is bonded, or is formed integrally with, the other midsole.   
     
     
         7 . The sole structure according to  claim 6 , wherein
 the intended deformation portion is bent or narrowed so as to be recessed rearward.