Shoe with ventilation system

Abstract

A shoe comprising upper, bottom fixed to the upper, ventilation system and insole disposed above the bottom and obtained by injection molding of polyurethane foam. The ventilation system is integrated inside the insole in such a way not to interfere with the bottom and with an outsole that must be applied under the bottom.

1 . A method of producing an insole for a shoe comprising a ventilation system, the method comprising:
 placement of said ventilation system inside a mold for injection molding of polyurethane foam, in such a way to form a lower layer of polyurethane foam disposed under the ventilation system with borders folded in such a way to surround the peripheral borders of said ventilation system.   
     
     
         2 . The method as claimed in  claim 1 , wherein said ventilation system is obtained:
 connection to a pump of a lower sheet, by means of a connection pipe, said lower sheet having the shape of the front of a foot and being provided with deformable spacers that protrude upward,   connection to said pump of an air outlet pipe, and;   application of an upper sheet on said pump and said lower sheet in order to form a wrapping between lower sheet and upper sheet generating a chamber, said upper sheet being provided with holes in communication with said chamber of the wrapping.   
     
     
         3 . The method as claimed in  claim 2 , wherein said pump is obtained by coupling a rigid lower semibody and a deformable upper semibody to form a pumping chamber and during the injection of polyurethane foam, the chamber of the pump is maintained at a pressure of approximately two atmospheres. 
     
     
         4 . The method as claimed in  claim 2 , wherein said upper sheet is made of leather or imitation leather and is sewn to a peripheral part of said lower sheet and said pump. 
     
     
         5 . The method as claimed in  claim 2 , wherein during the molding process the upper sheet is fitted to a lid of the mold by pins of the lid and said pump is pushed by pins of a die of the mold. 
     
     
         6 . An insole obtained by the method claimed in  claim 1 , wherein said insole comprises a lower layer of polyurethane foam obtained by injection molding, disposed under a ventilation system with borders folded in such a way to surround the peripheral borders of said ventilation system. 
     
     
         7 . The insole as claimed in  claim 5 , wherein said ventilation system comprises:
 a pump that forms an air chamber disposed in the user's heel area;   a lower sheet provided with a plurality of deformable spacers that protrude upward and disposed in correspondence with the front part of the foot;   an upper sheet disposed on the pump and on the lower sheet in order to form a wrapping between lower sheet and upper sheet generating a chamber, said upper sheet being provided with holes in communication with said chamber of the wrapping to extract air from inside the shoe;   a connection pipe connecting the chamber of the wrapping to the chamber of the pump, and;   an air outlet conduit connecting the chamber of the pump with the outside of the shoe for air ejection.   
     
     
         8 . The insole as claimed in  claim 7 , wherein said upper sheet is made of leather or imitation leather, is shaped as a foot and is disposed above the folded borders of the lower layer of polyurethane foam. 
     
     
         9 . The insole as claimed in  claim 7 , wherein said pump comprises: a lower semibody made of hard thermoplastic polyurethane (TPU) with Shore A hardness higher than 95 and an upper semibody made of soft thermoplastic polyurethane (TPU) with Shore A hardness lower than 65. 
     
     
         10 . The insole as claimed in  claim 7 , wherein said ventilation system further comprises:
 a first non-return valve disposed between said pump and said air outlet conduit to permit air flow from the chamber of the pump to the air outlet conduit and not in the reverse direction, and;   a second non-return valve disposed between said pump and said connection conduit to permit air flow from the connection conduit towards toward the chamber of the pump and not in the reverse direction.   
     
     
         11 . The insole as claimed in  claim 10 , wherein said first and second non-return valves are disposed inside corresponding channels of a valve unit formed of a rectangular block disposed in the front part of said pump. 
     
     
         12 . A shoe comprising:
 an upper, and;   a bottom fixed to the upper,   wherein the shoe comprises an insole as claimed in  claim 5 .   
     
     
         13 . The shoe as claimed in  claim 12 , wherein the shoe is an accident-prevention shoe, comprising a metal plate or Kevlar sheet disposed in the bottom or in an outsole applied under the bottom.