Shoe Sole Having Diagonal Groove

Abstract

A shoe sole including: an outsole having a tread surface to be in contact with a road surface; and a midsole arranged on the outsole, wherein: the midsole is exposed in a central section of a rear foot section and an arch section; in the central section and a lateral side section of the rear foot section of the shoe sole, a diagonal groove is formed extending in a diagonal front-rear direction in the rear foot section to an outer edge of a lateral side of the rear foot section; an angle β, formed between a virtual center line of the diagonal groove and a longitudinal axis connecting between a center of a heel and a middle point between a big-toe ball and a little-toe ball, is set in a range of 12° to 35°; and a virtual intersection point between the longitudinal axis and the center line is set within a range of 21% to 43% of a full length of the longitudinal axis of the shoe sole from a posterior end of the shoe sole, the diagonal groove extending to a point anterior and medial to the intersection point.

1 . A shoe sole comprising: an outsole having a tread surface to be in contact with a road surface; and a midsole arranged on the outsole, wherein:
 in a central section and a lateral side section of a rear foot section of the shoe sole, a diagonal groove is formed extending in a diagonal front-rear direction in the rear foot section to an outer edge of a lateral side of the rear foot section;   an angle, formed by a virtual center line of the diagonal groove and a longitudinal axis connecting between a center of a heel and a middle point between a big-toe ball and a little-toe ball, is set in a range of 12° to 35°; and   a virtual intersection point O between the longitudinal axis and the center line is set within a range of 21% to 43% of a full length of the longitudinal axis of the shoe sole from a posterior end of the shoe sole, the diagonal groove extending to a point anterior and medial to the intersection point.   
     
     
         2 . The shoe sole according to  claim 1 , wherein:
 the diagonal groove includes a front section located anterior to the intersection point, and a rear section located posterior to the intersection point; and   a volume of the diagonal groove in the rear section is larger than a volume of the diagonal groove in the front section.   
     
     
         3 . The shoe sole according to  claim 1 , wherein the diagonal groove is unextended to a medial edge of the shoe sole. 
     
     
         4 . The shoe sole according to  claim 1 , wherein the diagonal groove of the outsole flares toward a diagonally posterior direction. 
     
     
         5 . The shoe sole according to  claim 1 , further comprising a transversal groove extending in a direction perpendicular to the diagonal groove. 
     
     
         6 . The shoe sole according to  claim 1 , wherein:
 the outsole is divided into pieces arranged in a front foot section and in the rear foot section, thereby leaving uncovered an arch section between the front foot section and the rear foot section;   a reinforcement member formed by a non-foamed body of a resin is attached on a lower surface of the midsole in the arch section; and   the reinforcement member has a diagonal section extending generally parallel to the diagonal groove, and the diagonal section is arranged in a vicinity of the diagonal groove and anterior to the diagonal groove.   
     
     
         7 . A shoe sole comprising: an outsole having a tread surface to be in contact with a road surface; and a midsole arranged on the outsole, the shoe sole supporting a foot in a front foot section, an arch section, and a rear foot section, wherein:
 the outsole is divided into pieces arranged in the front foot section and in the rear foot section, thereby leaving uncovered the arch section, and is formed in the rear foot section in a U shape, with a central section cut out between a medial side and a lateral side of the foot;   the midsole is exposed in the arch section and the central section of the rear foot section;   a diagonal groove is formed in the midsole in the central section of the rear foot section and in the outsole in a lateral side section of the rear foot section, the diagonal groove extending in a diagonal front-rear direction in the rear foot section to an outer edge of the lateral side of the rear foot section;   an angle, formed by a virtual center line of the diagonal groove and a longitudinal axis connecting between a center of a heel and a middle point between a big-toe ball and a little-toe ball, is set in a range of 12° to 35°; and   a virtual intersection point between the longitudinal axis and the center line is arranged within a region from a rear half section of the arch section to a front half section of the rear foot section.   
     
     
         8 . The shoe sole according to  claim 7 , wherein a position of the virtual intersection point is arranged anterior to a centroid of the central section. 
     
     
         9 . The shoe sole according to  claim 8 , wherein:
 the diagonal groove formed in the midsole in the central section of the rear foot section is defined by one pair of first and second edge lines and which face each other;   the diagonal groove formed in the outsole is defined by one pair of third and fourth edge lines and which face each other; and   the third and fourth edge lines and are generally parallel to the first and second edge lines and, respectively, or flare to form an angle therebetween larger than an angle formed by the first and second edge lines and.   
     
     
         10 . The shoe sole according to  claim 7 , wherein:
 the diagonal groove extends to a medial side section of the midsole in the arch section; and   an average value of a cross-sectional area perpendicular to the center line of the diagonal groove in the arch section is smaller than an average value of a cross-sectional area perpendicular to the center line of the diagonal groove in the central section of the rear foot section in the midsole.   
     
     
         11 . The shoe sole according to  claim 7 , wherein:
 the diagonal groove is unextended to an edge of the medial side section of the midsole in the arch section; and   a tip of the diagonal groove is arranged posterior to an anterior end of the arch section.   
     
     
         12 . The shoe sole according to  claim 7 , wherein the diagonal groove of the outsole flares toward a diagonally posterior direction. 
     
     
         13 . The shoe sole according to  claim 7 , further comprising a transversal groove perpendicular to the diagonal groove. 
     
     
         14 . The shoe sole according to  claim 7 , wherein:
 a reinforcement member formed by a non-foamed body of a resin is attached to a lower surface of the midsole in the arch section; and   the reinforcement member has a diagonal section extending generally parallel to the diagonal groove, and the diagonal section is arranged in a vicinity of the diagonal groove and anterior to the diagonal groove.   
     
     
         15 . The shoe sole according to  claim 14 , wherein: the diagonal section extends to the front foot section. 
     
     
         16 . The shoe sole according to  claim 15 , wherein:
 the reinforcement member further includes a lateral side section extending along a lateral edge of the midsole in the arch section; and   the lower surface of the midsole is exposed between the lateral side section and the diagonal section.   
     
     
         17 . A shoe sole comprising: an outsole having a tread surface to be in contact with a road surface; and a midsole arranged on the outsole, the shoe sole supporting a foot in a front foot section, an arch section, and a rear foot section, wherein:
 the outsole is divided into pieces arranged in the front foot section and in the rear foot section, thereby leaving uncovered the arch section;   a diagonal groove is formed in the midsole and the outsole, the diagonal groove extending in a diagonal front-rear direction in the rear foot section to an outer edge of a lateral side of the rear foot section;   an angle, formed by a virtual center line of the diagonal groove and a longitudinal axis connecting between a center of a heel and a middle point between a big-toe ball and a little-toe ball, is set in a range of 12° to 35°;   a virtual intersection point between the longitudinal axis and the center line is arranged within a region from a rear half section of the arch section to a front half section of the rear foot section;   a reinforcement member formed by a non-foamed body of a resin is attached on a lower surface of the midsole in the arch section; and   the reinforcement member has a diagonal section extending generally parallel to the diagonal groove, and the diagonal section is arranged in a vicinity of the diagonal groove and anterior to the diagonal groove.   
     
     
         18 . The shoe sole according to  claim 17 , wherein the diagonal section extends to the front foot section. 
     
     
         19 . The shoe sole according to  claim 18 , wherein:
 the reinforcement member further includes a lateral side section extending along a lateral side of the midsole in the arch section; and   the lower surface of the midsole is exposed between the lateral side section and the diagonal section.