Shoe sole with reinforcing structure

Abstract

This invention relates to a shoe sole that solves the problems on weight saving in shoes, prevention of distortion, improvement in the fitting property and prevention of upthrust simultaneously. The reinforcing member 3 for reinforcing a part of the midsole 2 is arranged so that the top surface 36 of the second arch 3 c and the bottom surface 29 of the first arch 2 c are opposite to each other. At least a part of the bottom surface 29 of the first arch is not in contact with a part of the top surface 36 of the second arch in vertically spaced relationship to each other, thereby that the non-contact areas of the first arch 2 c and the second arch 3 c can be deformed independently from each other when impact load of landing is applied.

1 - 19 . (canceled) 
     
     
         20 . A shoe sole comprising:
 a midsole having a foot bearing surface and a bottom surface, the bottom surface including a middle foot portion, a forefoot portion, and a rear foot portion,   an outer sole having a ground contacting surface and a top surface, the outer sole being attached to the forefoot portion and the rear foot portion of the bottom surface of the midsole,   a first arch formed in the bottom surface of the midsole at the middle foot portion, a bottom surface of the first arch being concave downward, and   a reinforcing member for the middle foot portion, the reinforcing member comprising:   a second arch, the first and second arches juxtaposed on each other, the top surface of the second arch being convex upwards toward the bottom surface of the first arch,   wherein portions of the top surface of the second arch and the bottom surface of the first arch are in spaced apart relationship to each other and the portions deform independently from each other upon application of an impact load to the sole,   wherein the second arch has a greater Young's modulus than the first arch, and   a film-like member fixed to the first arch, the film-like member having a greater Young's modulus than the Young's modulus of the first arch, the film-like member having a thickness that is less than the second arch of the reinforcing member, the film-like member permitting but minimizing sinking down of the first arch.   
     
     
         21 . A shoe sole according to  claim 20 , wherein
 a thickness of the film-like member is set within a range of 0.01 mm to 0.5 mm.   
     
     
         22 . A shoe sole according to  claim 20 , wherein
 a ratio of product T 91 ·E 91  between the average thickness T 91  and the Young's modulus E 91  of the film-like member to product T 3c ·E 3c  between the average thickness T 3c  and the Young's modulus E 3c  of the second arch  3   c  is set by using a formula (1) of
   1/1000 ≦T   91   ·E   91 /( T   3c   ·E   3c )≦1/4   (1)
 
   
     
     
         23 . A shoe sole with a reinforcing structure, comprising: an outer sole having a ground contact surface and a top surface opposite to the ground contact surface; a midsole having a top surface and a bottom surface, the bottom surface being attached to the top surface of the outer sole and covering the top surface of the outer sole; and a reinforcing member for reinforcing a part of the midsole, wherein
 the midsole has a first arch positioned between forefoot and rear foot portions of the midsole,   the first arch is formed of resin foam and has a bottom surface,   the reinforcing member has a second arch, a fore end part located in front of the second arch and a rear end part located in the rear of the second arch,   the second arch has a top surface and a bottom surface,   the second arch located to be covered with the first arch,   the fore end part of the reinforcing member bonded to at least either the midsole or the outer sole in front of the first arch,   the rear end part of the reinforcing member bonded to at least either the midsole or the outer sole in the rear of the first arch,   the first arch and the second arch substantially unattached to the top surface of the outer sole and not in ground contact when the outer sole is grounded,   the second arch having a Young's modulus greater than a Young's modulus of the first arch,   a film-like member fixed to the first arch, the film-like member having a greater Young's modulus than the Young's modulus of the first arch, the film-like member having a thickness that is less than the second arch of the reinforcing member, the film-like member permitting but minimizing sinking down of the first arch, wherein   the reinforcing member arranged so that the top surface of the second arch and the bottom surface of the first arch are opposite to each other, and   at least a part of the bottom surface of the first arch not in contact with the top surface of the second arch in vertically spaced relationship to each other,   whereby non-contact areas of the first arch and the second arch can be deformed independently from each other when the impact load of landing is applied.   
     
     
         24 . A shoe sole according to  claim 23 , wherein
 when the impact load of landing is applied, downward displacement of the non-contact area of the bottom surface of the first arch is set to be larger than that of the non-contact area of the top surface of the second arch.   
     
     
         25 . A shoe sole according to  claim 23 , wherein
 the reinforcing member has two side portions bonded to the midsole.   
     
     
         26 . A shoe sole according to  claim 23 , wherein
 the bottom surface of the first arch has a first curved surface which forms a concave surface and the top surface of the second arch has a second curved surface which is convex upwards.   
     
     
         27 . A shoe sole according to  claim 23 , wherein
 the bottom surface of the first arch and the top surface of the second arch define a domain, and   the domain is formed to be hollow.   
     
     
         28 . A shoe sole according to  claim 23 , wherein
 the bottom surface of the first arch and the top surface of the second arch define a domain, and   the domain is filled with a filler having a smaller Young's modulus than the midsole and capable of varying its volume.   
     
     
         29 . A shoe sole according to  claim 27 , wherein
 an entire peripheral edge of the reinforcing member is bonded to the midsole, thereby to seal the domain.   
     
     
         30 . A shoe sole according to  claim 28 , wherein
 an entire peripheral edge of the reinforcing member is bonded to the midsole, thereby to seal the domain.   
     
     
         31 . A shoe sole according to  claim 27 , wherein
 an opening passing through the second arch vertically is formed.   
     
     
         32 . A shoe sole according to  claim 23 , wherein
 the first arch is formed of foam of ethylene-vinyl acetate copolymer, and   the reinforcing member is formed of non-foam of polyurethane, foam or non-foam of ethylene-vinyl acetate copolymer.   
     
     
         33 . A shoe sole according to  claim 23 , wherein
 the reinforcing member further comprises medial and lateral side portions on the medial side and   the lateral side of a foot of the second arch, and   the medial and lateral side portions of the reinforcing member are bonded to the midsole.   
     
     
         34 . A shoe sole according to  claim 23 , wherein
 the outer sole is separated into a fore foot part and a rear foot part at a position corresponding to an arch of the foot,   the fore foot part and the rear foot part of the outer sole each have a top surface and a bottom surface,   the fore end part of the reinforcing member is sandwiched in between the top surface of the fore foot part of the outer sole and the bottom surface of the midsole, and   the rear end part of the reinforcing member is sandwiched in between the top surface of the rear foot part of the outer sole and the bottom surface of the midsole.   
     
     
         35 . A shoe sole according to  claim 23 , wherein
 the midsole includes an upper midsole body and a lower midsole body,   the upper and lower midsole bodies are formed of an ethylene-vinyl acetate copolymer, and   the reinforcing member is bonded to the upper and lower midsole bodies with both of the fore end part and the rear end part of the reinforcing member sandwiched in between the upper midsole body and the lower midsole body.   
     
     
         36 . A shoe sole according to  claim 23 , further comprising a second reinforcing member arranged below the first reinforcing member. 
     
     
         37 . A shoe sole according to  claim 23 , wherein
 the center line of the first arch in the longitudinal direction and the center line of the second arch in the longitudinal direction are arranged at least just under a navicular bone, a cuboid bone or the cuneiform bone of the foot.   
     
     
         38 . A shoe sole according to  claim 23 , wherein
 the first arch has a top surface,   the top surface of the first arch has a third curved surface which is convex upwards so as to be approximately along with the arch of the foot.   
     
     
         39 . A shoe sole according to  claim 23 , wherein
 the bottom surface of the second arch has a fourth curved surface which forms a concave suffice recessed upwards.   
     
     
         40 . A shoe sole according to  claim 23 , wherein
 a thickness of the film-like member is set within a range of 0.01 mm to 0.5 mm.   
     
     
         41 . A shoe sole according to  claim 23 , wherein
 a ratio of product T 91 ·E 91  between the average thickness T 91  and the Young's modulus E 91  of the film-like member to product T 3c ·E 3c  between the average thickness T 3c  and the Young's modulus E 3c  of the second arch  3   c  is set by using a formula (1) of
   1/1000 ≦T   91   ·E   91 /( T   3c   ·E   3c )≦1/4   (1)
 
   
     
     
         42 . A shoe sole according to  claim 20 , wherein portions of the top surface of the second arch and portions of the bottom surface of the first arch are spaced apart from each other with only the film-like member as the intervening structure between the portions of the top surface of the second arch and the portions of the bottom suffice of the first arch. 
     
     
         43 . A shoe sole according to  claim 20 , wherein only the film-like member and portions of the second arch are positioned under portions of the bottom surface of the first arch. 
     
     
         44 . A shoe sole according to  claim 23 , wherein portions of the top surface of the second arch and portions of the bottom surface of the first arch are spaced apart from each other with only the film-like member as the intervening structure between the portions of the top surface of the second arch and the portions of the bottom surface of the first arch. 
     
     
         45 . A shoe sole according to  claim 23 , wherein only the film like member and portions of the second arch are positioned under portions of the bottom surface of the first arch.