Patent Publication Number: US-6904705-B2

Title: Shoe with permeable and breathable upper that covers at least partially an impermeable sole that is rendered breathable

Description:
BACKGROUND OF THE INVENTION 
   The present invention relates to a shoe in which the upper, of the permeable and breathable type such as natural leather, covers at least partially a sole that is impermeable because it is made of rubber or another elastomer and is rendered breathable. 
   Special shoes known as “driving moccasins”, which are manufactured by arranging, inside the wraparound leather upper, a layer of rubber with nubs that pass through suitable holes of the upper are more and more successful on the market. 
   The nubs constitute tread elements for resting on the ground. 
   Such rubber layer is sewn onto the leather of the upper before it is closed onto an upper tongue, which corresponds to the front part of the foot, with a hand-stitched seam. 
   A cleaning insole is applied internally over the rubber layer. 
   This provides a shoe that is highly flexible and adapts to the anatomy of the foot, increasing its sensitivity, which is critical for example while driving. 
   For this purpose, the rubber layer rises behind the heel so as to extend over the heel also with the through nubs, whereby to allow the heel to rest on a surface, while driving, without spoiling the leather. 
   The main problems that limit the use of shoes of this type are due mainly to the lack of moisture permeation caused by the layer of rubber that is interposed between the leather of the upper and the foot and to the lack of waterproofness caused by the immediate absorption of water which, through the stitched seams that pierce the rubber layer, immediately wets the cleaning insole and therefore the foot. 
   SUMMARY OF THE INVENTION 
   The aim of the present invention is to provide a shoe of the “driving moccasin” type that eliminates both of the drawbacks noted above in the background art, being at the same time breathable through the part below the sole of the foot and impermeable to water at least in the same region. 
   A consequent primary object is to provide a shoe that has substantially the same characteristics of grip on the ground in all conditions of use as known shoes of the “driving moccasin” type. 
   Another object is to increase user comfort. 
   Another object is to provide a shoe of the “driving moccasin” type that can be manufactured at a low cost and therefore sold at a competitive price. 
   Another object is to provide a shoe of the “driving moccasin” type that can be manufactured with conventional equipment and methods. 
   This aim and these and other objects that will become better apparent hereinafter are achieved by a shoe with a permeable and breathable upper that covers at least partially an impermeable sole that is rendered breathable, characterized in that it comprises a sole layer that is made of rubber or of another elastomer connected internally to a wraparound upper made of leather or similar material, said sole layer made of rubber or similar material having nubs that pass through suitable holes of the upper and constitute as a whole the tread, at least some of said nubs having at least one through hole, a breathable or perforated protective layer, a membrane that is permeable to vapor and impermeable to water and a breathable or perforated insole or anatomical inner sole being arranged in succession from below, at least at said holes of said nubs, above said sole layer made of rubber or other elastomer, said protective layer and said membrane having edges that are substantially adjacent and joined hermetically to said sole layer made of rubber or other elastomer and to said inner sole. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Further characteristics and advantages of the invention will become better apparent from the detailed description of an embodiment thereof, illustrated by way of non-limitative example in the accompanying drawings, wherein: 
       FIG. 1  is a longitudinal sectional view of a shoe according to the invention; 
       FIG. 2  is an exploded view of two components of the shoe of  FIG. 1 ; 
       FIG. 3  is an enlarged-scale view of the two components of  FIG. 2  in the assembled condition; 
       FIG. 4  is a sectional view of the components of the shoe of  FIG. 1  prior to final assembly; 
       FIG. 5  is a sectional view of a mold that can be used to assemble components of the shoe according to the invention; 
       FIG. 6  is a transverse sectional view of the shoe of FIG.  1 . 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   With reference to the figures, a shoe of the “driving moccasin” type is generally designated by the reference numeral  10  and comprises a sole layer  11  made of rubber or other elastomer, which is arranged inside a wraparound upper  12  made of leather. 
   The sole layer  11  has nubs  13  that pass through suitable holes  14  of the upper  12 . 
   The nubs  13  constitute tread elements for resting on the ground. 
   The sole layer  11  made of rubber is connected along a flat surface, by means of adhesive and/or stitched seams  15 , to the leather of the upper  12 . 
   At least some of said nubs  13  have at least one through hole  16  which, as will become better apparent hereinafter, allows the exchange of water vapor with the inside of the shoe  10 . 
   A protective (filler) layer  17  and a membrane  18  that is permeable to vapor and impermeable to water are arranged above the rubber sole layer  11 , particularly at the holes  16 , in succession from below; said layer and said membrane have substantially adjacent and overlapping edges that are joined sealingly by a peripheral element  20  made of a plastic material such as TPU (thermoplastic polyurethane) or TR (thermoplastic rubber) or PU (polyurethane), which is molded or glued or heat-sealed so as to also seal the stitched seams  15 . 
   In an upward region there is an anatomical inner sole or insole  21 , which is breathable or perforated and is molded or spot-glued. 
   The membrane  18  is preferably made of a material such as the one commonly known as Gore-Tex™. 
   The protective layer  17  is made of perforated or breathable material, such as hydrophilic felt, gelling rubber such as DRYZ™ provided by DICON TECHNOLOGIES, open-cell rubbers. 
   The peripheral element  20  can be sealed perimetrically to the sole layer  11  and externally to the stitched seams  15  by non-soluble and permanent gluing or by way of other known methods (high frequency, direct injection molding, etc). 
   As an alternative, the peripheral element  20  can be obtained by injection-molding in a mold  22  (composed of a lower mold part  23  and an upper mold part  24 ), in which the inner sole  21  is inserted as an insert and is coupled in discrete points, or only perimetrically, to the membrane  18 , which is in turn coupled to the protective layer  17 , made thinner at a perimetric region thereof so that the plastic material of the subsequent injection of plastic material that forms the perimetric sealing element  20  is able to bond with the membrane  18  and the inner sole  21  in order to seal them against water, optionally with the aid of suitable adhesives. 
   As shown in  FIG. 5 , the inner sole  21  is retained with the edges  30  between the mold parts  23  and  24 , while in the upper mold part  24  a seat  31  is provided for the injection-molding of said peripheral element  20  and the flash trimmers  24   a  that leave a central clear area  32 . 
   In the central portion, at the pronation region, it is possible to insert in the mold  22  (in the free region  32  between the flash trimmers  24   a ), a breathable or absorbent filler layer  25  (hydrophilic felt, gelling rubber such as DRYZ, open-cell rubbers or perforated layers, et cetera). 
   The layer  25  can also be applied after the molding of the peripheral element  20 . 
   The upper  12  is sealed with the peripheral element  20  and with the sole layer  11 , so that the connecting stitched seams  15  cannot convey water into the inner sole  21 . 
   The holes  16  are therefore connected to the inside of the shoe  10 , as regards vapor permeability, through the breathable layer  17 , the membrane  18 , the optional breathable layer  25 , and the breathable and/or perforated inner sole  21 . 
   The peripheral element  20  can be glued along its outer edges  26  to the upper  12  so as to slow the water absorption of the upper  12 . 
   Water, in order to wet the foot, would have to rise beyond the edges  26  of the peripheral element  20 , taking a very long time and in any case keeping the inner sole  21  dry. 
   The sealing of the membrane  18  by way of the peripheral element  20  can be obtained also by coupling such membrane to meshes or nets (not shown in the figures), instead of the protective layer  17 , which ensure the penetration of the perimetric sealing plastic material. 
   As an alternative, the perimeter region of the membrane  18  can be left unprotected so that the plastic of the peripheral element  20  adheres to it directly. 
   The shoe  10  is completed by surrounding the edges of an upper tongue  27  with the edges of the upper  12  and by joining them with a hand-stitched seam  28 . 
   In practice it has been found that the intended aim and objects of the present invention have been achieved. 
   A shoe of the “driving moccasin” type has in fact been provided which is simultaneously breathable through the part that lies under the sole of the foot and impermeable to water at least in the same region, and this helps to increase user comfort. 
   The shoe substantially has the same ground grip characteristics in all conditions of use as known shoes of the “driving moccasin” type, and in relation to this characteristic it is merely provided with the addition of the holes  16 . 
   The shoe can be manufactured with conventional equipment and techniques and can also be manufactured at a low cost and therefore sold at a competitive price. 
   The invention thus conceived is susceptible of numerous modifications and variations, all of which are within the scope of the appended claims. 
   All the details may further be replaced with other technically equivalent elements. 
   In practice, the materials used, so long as they are compatible with the contingent use, as well as the dimensions, may be any according to requirements. 
   The disclosures in Italian Patent Application No. PD2002A000153 from which this application claims priority are incorporated herein by reference.