Patent Publication Number: US-2011061263-A1

Title: Flexible insole for closed shoes

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application claims priority under 35 U.S.C. §119 to Swiss Patent Application No. CH-01429/09 filed Sep. 16, 2009, the entire contents of which are incorporated herein by reference. 
     FIELD OF THE INVENTION 
     The instant invention relates to a flexible insole or insertable sole, respectively, for closed shoes comprising a one-piece base insole layer and an upper sole made of breathable material, which is directly or indirectly laminated thereabove, wherein the one-piece base insole layer has an inner surface facing the foot and an outer surface facing away from the foot and the base insole layer has protrusions on one side. 
     BACKGROUND OF THE INVENTION 
     In recent years, more and more shoes have been offered on the market, which are described as being breathable. In particular, these shoes are also described as vented shoes. Traditionally, the ventilation typically takes place to a very small degree by means of the upper leather and to a larger degree by means of the absorption of the sweat by the socks, via which the sweat can also be transported to the outside and can evaporate there. The removal of the air, which is enriched with sweat, takes place by means of the outsole only in the minority of cases, with said outsole being provided in this case with corresponding ventilation openings and wherein a semi-permeable membrane is attached to the outsole. 
     However, such shoes, which are described as vented shoes, are frequently provided with insoles or insertable soles, respectively, which are provided with a certain perforation, which is to suggest the appearance of the ventilation. In reality, an insole or insertable sole, respectively, is designed in multiple layers and the individual layers are holohedrally adhered or laminated to one another, respectively. In the case of such a holohedral adhesion, a good portion of the perforations clogs and accordingly the ventilation is extremely poor. 
     The actual outsoles of the shoes are to be robust and abrasion-resistant, which is at the same time virtually synonymous with the sole being relatively hard. However, for the walking comfort, the soles of the shoes should absorb at least a portion of the shocks occurring in response to each step. Correspondingly, diverse outsoles are also known, which have an intermediate layer made of shock-absorbing material at least in the heel area. It is not known to us to solve this problem via the insole or insertable sole, respectively. According to our knowledge, virtually all flexible insoles or insertable soles, respectively, are provided with a base insole layer, which serves a sole function. However, the requirements of a sole for different functions are actually concentrate on two main areas, namely in the heel area on the one hand, where the perspiration is relatively low and in a front area, in which the shock-absorbing function is low, but the perspiration is instead considerable. 
     For example, an insole for a shoe comprising a base insole layer, which encompasses protrusions extending upwards from the outer surface towards the inner surface, all of which protrusions are hollow and encompass ventilation openings on the apex of the protrusions, is known from WO 02/11570, for example. Depending on the exemplary embodiment, the protrusions are designed so as to either have the same height across the entire surface or are designed so as to have different heights, wherein the different heights of the protrusions lead to a footbed-like structure of the insole. The function of the sole is the same across the entire surface. Even though it is explained in the document that the protrusions also have a shock-absorbing effect, because the protrusions are elastic, the effect created thereby is extremely counter-productive, because air, which is enriched with sweat and which is close to the saturation limit is located in the cavities of the hollow protrusions, a condensation of the sweat takes place in response to each step and this wetness is also sucked upwards through the pores again in response to virtually each step. This interaction was identified. Accordingly, DE202004008508U proposes to design such a base insole layer comprising protrusions such that the protrusions are alternately attached to the inner surface and to the outer surface. It is also proposed herein to vary the height of the protrusions across the sole. 
     The applicant, who specialized in particular on the development and sale of insoles or insertable soles, respectively, comprising foot reflex zone massage elevations, has in particular also determined that the application of such a massage layer above the base insole layer again complicates the problem, because this further counteracts the ventilation and, secondly, because the design of hollow protrusions, the height of which is chosen such that they have a sufficient shock-absorbing effect, as a whole becomes too thick for an insertable sole. 
     U.S. Pat. No. 4,896,441 clearly discloses this mentioned problem. Protrusions in the form of nibs comprising rounded ends and rounded cross section are attached herein to the inner surface of the side facing the foot, with said nibs encompassing different heights and thicknesses and thus forming a footbed. An alternative also provides for all of these protrusions, which are also again arranged on the inner surface again, to be designed with the same heights. As in the case of the invention, this latter version can then also bear on an outsole comprising an orthopedic footbed design. 
     While the first alternative has the described problems, the second version has the disadvantage that the foot virtually covers the ventilation and this ventilation is ineffective. 
     SUMMARY OF THE INVENTION 
     It is consequently the complex object of the instant invention to design a flexible insole or insertable sole, respectively, of the afore-mentioned type such that the afore-mentioned problems are overcome or at least reduced considerably. 
     This object is solved by means of a flexible insole or insertable sole, respectively, according to the preamble of patent claim  1 , wherein the base insole layer made of shock-absorbing synthetic material is divided into two functionally different zones, wherein large-surface frustoconical protrusions form a shock-absorbing zone in the heel area and the remaining area is designed as ventilation zone, wherein the protrusions here encompass a similar basic design, but the upper cover surface of the frustoconical protrusions in the shock-absorbing zone are between 4 to 10 times greater than the cover surfaces of the protrusions in the ventilation zone, wherein the protrusions in the ventilation zone are spaced apart and ventilation holes are arranged herein. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Further advantageous embodiments of the object of the invention as claimed in the dependent patent claims are defined in the subsequent description with reference to the attached drawings. 
       A preferred exemplary embodiment of the object of the invention is illustrated in the drawing and will be described below: 
         FIG. 1  shows a view onto an insertable sole or insole with view onto the upper sole; 
         FIG. 2  shows such an insertable sole or insole with view onto the outer surface of the base insole; 
         FIG. 3  shows such an insertable insole or insole according to  FIGS. 1 and 2  in a side view; while 
         FIG. 4  explains the adhesion between the base insole layer and the massage layer. 
         FIG. 5  shows an alternative of the sole according to the invention in the case of which the base insole layer is designed so as to be consistent, while the massage layer is designed differently and the connection between the different layers takes place by means of sewing. 
         FIG. 6  shows the sole according to  FIG. 5  with view onto the massage layer. 
     
    
    
     DETAIL DESCRIPTION OF THE INVENTION 
     On principle, the insole or insertable sole as a whole is identified with  1 . It always has a base insole layer  2 . This base insole layer  2  has an outer surface  3  and an inner surface  4 . The side facing away from the foot is identified as outer surface  3 , while the side facing the foot is identified as inner surface. Preferably, the outer surface  3 , thus the side facing away from the foot, is provided with protrusions, while the side facing the foot, thus the inner surface  4 , is designed as planar surface. All of the protrusions have a surface area in the form of elongate rectangles. All of the longitudinal edges of these surface areas run parallel to one another and at right angles to the longitudinal foot direction. It can clearly be seen that the protrusions nonetheless form different structures and thus form two different functional zones. A first functional zone  20  serves the purpose of shock absorption and is identified with  20 , while a second functional zone serves the purpose of ventilation and is identified with  30 . The first functional zone  20  is located in the heel area, while the second functional zone  30  covers the rest of the sole. The protrusions in the first functional zone for the shock absorption are identified with  5 , those in the second functional zone for the ventilation are identified with  6 . In the basic design, the protrusions are the same in that they always form the shape of rectangular truncated cones. 
     The protrusions  5  of the first functional zone  20  are considerably larger than the protrusions  6  in the second functional zone. As already mentioned, the protrusions in the first functional zone  20  serve the purpose of shock absorption. The surface area of the frustoconical protrusions in the functional zone  20  has a side ratio of approximately 2 to 3. The cover surface of these protrusions in the first functional zone has a side ratio of approximately 1 to 2. The protrusions  5  in the functional zone, which is to be described herein, for the shock absorption are arranged such that the surface areas of adjacent protrusions touch on the longitudinal edge as well as on the wide edge. Consequently, they are arranged close together. In a preferred exemplary embodiment, the lengths of the surface areas of the protrusions are 15 millimeters and those of the wide edge are 10 millimeters. Contrary thereto, the lengths of the surface areas in this example are approximately 10 millimeters and the wide edges are 5 millimeters. In response to the shock absorption, the protrusions change their shape, wherein they simultaneously at least approximately maintain the volume. In more specific terms, this means that the protrusions change slightly in height, wherein the inclined side surfaces of the truncated cones simultaneously bulge outwardly in a rounded manner. The vibrations created in response to a step are thereby absorbed in the material to a large extent. All of the protrusions are filled fully and are not permeable to air. The entire heel area, thus the area of the first functional zone  20 , is also free from perforations. This also makes sense, because according to experience, the perspiration in the heel area is low. 
     As already mentioned, the protrusions  6  in the second functional area  30  are designed so as to be much smaller. Contrary to the protrusions in the functional zone  20  for the shock absorption, these protrusions only have to absorb small impact forces and cause a small vibration absorption. These protrusions are thus arranged relatively far from one another so as to provide a relatively large air volume, so as to prevent a saturation of this air with sweat steam as for as possible. This is attained in that the protrusions, which run in rows like the afore-described protrusions  5 , are arranged herein, however, so as to be distances on the outer surface  3 . In other words, the longitudinal edges and the wide edges of adjacent protrusions do not touch. The protrusions herein have a cover surface, the longitudinal edges of which also have a longitudinal ratio of 2 to 1 to the width. In more specific terms, the cover surfaces have a length of approximately 4 millimeters and a width of 2 millimeters. In the surface area of the truncated cones, the lengths of the longitudinal edges are 5 millimeters and the length of the width is 3 millimeters. Upon consequently comparing the cover surfaces of the protrusions in the first zone to the cover surfaces of the protrusions in the second zone, they have an area ratio of approximately 1 to 6. In more specific terms, this ratio is preferably approximately in the magnitude of 1 to 4 to 1 to 10. 
     The longitudinal edges of adjacent protrusions  6  in the second functional area are spaced apart from one another by approximately the width of the cover surface of these protrusions. In more specific terms, this distance will preferably be between 1 to 4 millimeters. A planar area of the outer surface  3  of the base insole layer  2  is thus located between the rows of protrusions. The sense of the spacing and of the arrangement of the protrusions in rows does not only lie in attaining the largest possible air volume underneath the outer surface  3  of the base insole layer  2 , but also to facilitate the unrolling motion of the foot through this. 
     The protrusions in the second functional zone  2  are furthermore also arranged such that the protrusions of one row are offset to one another relative to the protrusions of the adjacent row by approximately half the protrusion length including the space between two adjacent protrusions of the same row. This offset has the effect that the sole has a sufficient stiffness at right angles to the longitudinal direction, because a tilting moment at right angles to the longitudinal direction is not desired. 
     Accordingly, perforations  7  are also attached in this second functional zone  30 , which serves the purpose of ventilation. These perforations  7  are distributed evenly. They are in each case located between two adjacent rows, namely such that they are arranged between two adjacent protrusions in the one row and approximately in the center relative to the longitudinal edge of that protrusion in the row located in front of it. 
     A massage layer  10  is attached above the base insole layer  2  according to the invention. This massage layer  10  is illustrated in  FIGS. 3 and 4 . Advantageously, the massage layer  10  consists of a latex comprising fine, open pores. Such a layer is breathable. The massage layer  10  has elevations  11 , which are arranged across the entire insole or insertable sole, as is illustrated in  FIG. 1 , according to the teaching of reflex zone massage. The distribution of the elevations according to  FIG. 1  forms the distribution, which is effective for a general well-being. So that the air can reach from the area above the insole or insertable sole into the area of the second functional zone  30 , it is necessary to not holohedrally adhere the massage layer to the base insole layer  2 .  FIG. 4  shows a preferred manner of adhesion. Here, the massage layer  10  is provided with adhesive only along the edge on one side in the edge area  14 . This area is identified with  14 . In the heel area, however, the adhesive area  15  can be holohedral, because this surface corresponds to the first functional zone  20 , in which air-permeable perforations are not necessary. Due to the fact that the inner surface  4  of the base insole layer  2  is planar, an adhesion only along the edge is a reliable adhesion, which is holohedral and not only punctiform, as is the case in the case of known base insole layers according to the state of the art. Finally, an upper sole  13  is also attached above the breathable massage layer  10 . The upper sole  13  can be provided with a power point coating on the adhesive side, so that the sole is evenly connected to the massage layer  10 . However, it is also possible here to adhere the upper solve  13  to the massage layer only along the edge. A further, likewise preferred solution can be that all layers are sewn to one another at least along the edge. Tests in which a seam was additionally attached through all three layers, also around the elevation  11 , led to particularly preferred results. 
     Instead of with elevations according to the embodiment illustrated in  FIGS. 1 and 3 , the massage layer  10  can be realized with slightly elevated massage protrusions, which only cause a slight stimulation of the sole of the foot. According to examinations, such protrusions cause a stimulation of the digestive tract and are to thus cause a weight loss. Such a solution is illustrated in  FIGS. 5 and 6 . In the case of these solutions, the upper sole  13  has recesses  16 , which run around the protruding areas  17 , so as to leave open the massage protrusions  18  accordingly. It can also be seen clearly here that the upper sole  13 , the massage layer  10  and the base insole layer  2  are connected to one another by means of seams  19 . On the one hand, these seams  19  run along the entire sole contour and, on the other hand along the contour of the differently protruding areas  17  on the edges of the recess  16 . 
     Finally, reference is also made to the different preferred materials. As already mentioned, the upper sole is preferably made of leather or textile material. These materials are not only breathable but also absorb moisture. Through this, the wetness is absorbed by the skin and evaporates while being conveyed through the breathable layers into the functional zone for the ventilation. Accordingly, the upper sole  13  can also additionally be provided with perforations. These perforations are not mandatory in the case of the material selection preferred herein and are only attached in the front foot area, as it is shown in  FIG. 1 . 
     Preferably, the massage layer is made of latex. Other elastomers, for example synthetic rubber, thermoplastic rubber or block copolymers as well as thermoplastics are a possibility, wherein antibacterial additives are preferably added to these materials. In the event that the massage layer  10  is realized in the embodiment according to  FIGS. 5 and 6 , is thus provided with protrusions, the latex versions, which are not particularly abrasion-resistant, are hardly a possibility. 
     In particular, elastomers in the form of thermoplastics and block copolymers are a possibility for the base insole layer  2 . The materials specified herein are only examples, wherein the person of skill in the art in the field of the production of soles can vary the material selection according to his own experiences. 
     LIST OF REFERENCE NUMERALS 
     
         
           1  insole or insertable sole 
           2  base insole layer 
           3  outer surface side facing away from the foot 
           4  inner surface side facing towards the foot 
           20  functional zone for shock absorption 
           30  functional zone for ventilation 
           5  protrusions in first functional zone 
           6  protrusions in second functional zone 
           7  perforations 
           10  massage layer 
           11  elevations 
           12  perforations 
           13  upper sole 
           14  adhesive area massage sole layer on base insole layer edge 
           15  heel adhesive area 
           16  recesses 
           17  protruding area 
           18  massage protrusions 
           19  seam