Sole Structure for Footwear

Abstract

The invention is directed to transmitting ground surface information to a foot sole of a shoe wearer accurately. Sole structure 1 includes a sole body 2 having a sole bottom surface 20 on a ground surface side and a sole top surface 21 on the opposite side thereof, a plurality of first protrusions 3 formed of elastic member and disposed on the sole bottom surface 20 , and a plurality of second protrusions 4 formed of elastic member, disposed on the sole top surface 21 and located at positions corresponding respectively to positions of the first protrusions 3 . A sectional shape of the first protrusion 3 is formed so that it gradually becomes smaller as it leaves the sole bottom surface 20 . A distal end portion of the first protrusion 3 is formed of an arcuate shaped surface that protrudes downwardly. A sectional shape of the second protrusion 4 is formed so that it gradually becomes smaller as it leaves the sole top surface 21 . A distal end portion of the second protrusion 4 is formed of an arcuate shaped surface that protrudes upwardly. An irregular shape of the foot sole contact surface of foot wear is formed by an irregular shape of the plurality of the second protrusions 4 on the sole top surface 21.

1 . A sole structure for footwear comprising:
 a sole body that includes a sole bottom surface disposed on a ground surface side and a sole top surface disposed on an opposite side thereof;   a plurality of first protrusions formed of elastic members and disposed on the sole bottom surface; and   a plurality of second protrusions formed of elastic members, disposed on the sole top surface and located at positions corresponding respectively to positions of the plurality of first protrusions,   wherein a sectional shape of the first protrusion is formed so that it gradually becomes smaller as it leaves the sole bottom surface and a distal end portion of the first protrusion has a convex surface that protrudes downwardly,   wherein a sectional shape of the second protrusion is formed so that it gradually becomes smaller as it leaves the sole top surface and a distal end portion of the second protrusion has a convex surface that protrudes upwardly,   wherein an irregular shape of a foot sole contact surface of foot wear is formed by an irregular shape of the plurality of the second protrusions on the sole top surface.   
     
     
         2 . The sole structure according to  claim 1 , wherein the first and second protrusions deform compressively at the time of contacting of the sole structure with the ground, an contact area of the first protrusion with the ground surface increasing as a load against the first protrusion increases, and a contact area of the second protrusion with a foot sole of a shoe wearer increasing as the contact area of the first protrusion with the ground increases. 
     
     
         3 . The sole structure according to  claim 1 , wherein the distal end portion of the first protrusion has a curve shaped surface that curves downwardly convexly and the distal end portion of the second protrusion has a curved shaped surface that curves upwardly convexly. 
     
     
         4 . The sole structure according to  claim 1 , wherein the distal end portion of the first protrusion or the second protrusion is formed of an arcuate shaped surface composed of single or a plurality of circular arcs. 
     
     
         5 . The sole structure according to  claim 1 , wherein an outside surface of the first protrusion forms an obtuse angle relative to the sole bottom surface and an outside surface of the second protrusion forms an obtuse angle relative to the sole top surface. 
     
     
         6 . The sole structure according to  claim 1 , wherein the distal end portion of the second protrusion is provided such that it directly contacts a bottom surface of an upper of footwear, or such that it directly constitutes the foot sole contact surface of foot wear. 
     
     
         7 . The sole structure according to  claim 1 , wherein the first protrusion has a hardness greater than a hardness of the second protrusion. 
     
     
         8 . The sole structure according to  claim 1 , wherein the first protrusion or the second protrusion has a cavity formed therein. 
     
     
         9 . The sole structure according to  claim 1 , wherein the first protrusion and the second protrusion are provided at a forefoot region and a midfoot region of the sole structure. 
     
     
         10 . The sole structure according to  claim 9 , wherein a distance between the first protrusions adjacent to each other and a distance between the second protrusions adjacent to each other are greater in a forefoot rear side region and the midfoot region than in a forefoot front side region of the sole structure. 
     
     
         11 . The sole structure according to  claim 9 , wherein in a forefoot rear side region and the midfoot region of the sole structure a distance between the first protrusions adjacent to each other and a distance between the second protrusions adjacent to each other are greater in a foot length direction than in a foot width direction of the sole structure. 
     
     
         12 . The sole structure according to  claim 9 , wherein each of the first protrusion and the second protrusion has a circular shape in a forefoot front side region of the sole structure and an elliptic shape that is long in a substantial foot length direction in a forefoot rear side region to the midfoot region as viewed in a bottom and a plane.