Abstract:
A shoe including cushioning elements housed in a tread sole adapted to come into contact with the ground, the cushioning elements including a plurality of cushioning capsules orientated in a manner such that they substantially follow a line on which the weight of a person is transferred during walking, that is, a podalic line; the cushioning capsules have different sizes and shapes that are geometrically similar to each other, constituting a series of modular elements adaptable to every shoe size and type.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims priority under 35 USC §119 to European Patent Application serial number EP 10154631.5, filed on Feb. 25, 2010, the entire disclosure of which is hereby incorporated by reference. 
     TECHNICAL FIELD OF THE INVENTION 
     The present invention refers to a shoe equipped with a sole, and/or other portions, that are cushioning. 
     The present invention also relates to a cushioning system of modular type comprising one or more base cushioning elements in the form of capsules with different sizes, but with shapes geometrically similar to each other. Such capsules are adapted to achieve a modular system of cushioning elements to be applied to the soles of all shoe types and are capable of defining, by means of a reduced number of elements, predetermined body load distribution lines on such soles. 
     DESCRIPTION OF RELATED ART 
     In the field of valuable footwear, soles can be equipped with cushioning inserts for improving walking comfort. These inserts are often chambers filled with liquid, air, gel or similar materials which, upon deformation, dampen the impact of the foot against the ground and/or mitigate impact hardness. Therefore, such inserts reduce the mechanical stress which acts on the foot. 
     A further improvement, e.g. present in the patent applications US2005/0241185 and US2005/0268490, is to place the inserts in the sole tips, which are stressed in larger extent. Indeed, biomechanics teaches that during pronation, the sole of the foot touches the ground along a line, called podalic line, visible for example in FIG. 1 of US-2005/0241185. 
     In US-2005/0241185, a chamber 38 is described, filled with fluid, which is extended approximately to the center of the sole and is enlarged beneath the metatarsus, zone 47. 
     Inside the chamber, a rigid element is present, called island 40. After walking, the fluid can be moved inside the chamber by moving around the island 40, and it follows the natural cycle of the pace. The rigid island 40 limits the comfort of the sole, and the chamber 38 is not sufficiently curved to be able to adequately follow the podalic line—without the constriction of its inner channels, which would prevent the fluid displacement. 
     In US-2005/0268490, inserts 40 of various shapes are described. These are made of polyurethane foam and are set in areas along the podalic line. The inserts are contained in seats of an insole, which lies on a tread sole 50. The latter is provided with projections 55 a  beneath the inserts 40, in a manner such that when walking, the projections 55 a  press against the inserts 40 and cushion the movement of the foot. The cooperation between projections 55 a  and inserts 40 a  on two different planes limits the effectiveness of the inserts 40, and complicates the structure of the shoe. 
     SUMMARY OF THE INVENTION 
     An object of the present invention is to improve the prior art. 
     Another object of the present invention is to obtain a shoe equipped with a sole which offers greater comfort with respect to the shoes of known type. 
     A further object of the present invention is to obtain a shoe equipped with a cushioning sole that can be made in a simple and economical manner. 
     Such objects are obtained by means of a sole equipped with cushioning elements of different shapes and sizes, positioned and oriented in a manner such that they follow a predetermined line. 
     The claims refer to preferred and advantageous embodiments of the invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Further characteristics and advantages of the present invention will be clearer from the exemplifying description of several versions of shoes and cushioning capsules, illustrated as an example in the drawing set, in which: 
         FIG. 1  shows a bottom view of a shoe using the modular system according to the present invention; 
         FIG. 2  shows a bottom view of another shoe version using the modular system according to the present invention; 
         FIG. 3  shows a bottom view of a cushioning element according to the present invention; 
         FIG. 4  shows, overturned, a section view along the IV-IV plane of the element of  FIG. 3 ; 
         FIG. 5  shows, overturned, a section view along the IV-IV plane of the element of  FIG. 3  according to another version of the present invention; 
         FIG. 6  shows, overturned, a section view along the IV-IV plane of the element of  FIG. 3  according to a further version of the present invention; 
         FIG. 7  shows a bottom view of another shoe version using the modular system according to the present invention; 
         FIG. 8  shows a section of a sole in which a base cushioning element is used in several parts of a shoe using the modular system according to the present invention; 
         FIGS. 9-27  show, seen from below, further versions of cushioning elements and arrangements of cushioning elements in soles of shoes using the modular system according to the invention; and 
         FIG. 28  shows a shoe sole with the indication of the line on which the weight of a person in transferred during walking. 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     With reference to the attached figures, several soles  12  are shown of shoes  10 ,  50 ,  60  according to the present invention, comprising several base cushioning elements  20  in the form of internally-hollow capsules. Such capsules are provided for coming into contact with the ground, and are filled with a gel, a liquid, or another similar fluid material or granular material of substantially incompressible type. 
     In the version of  FIG. 1  of the present invention, a shoe  10  is illustrated with a sole  12  which comprises six cushioning elements  20  filled with gel or another similar incompressible material. 
     In such version, all the base cushioning elements  20  essentially have the same drop form, but some have different sizes and are inserted in the sole with a different positioning and orientation, considering, for example, an axis of the cushioning element  20  which starts from the widest part and leads towards the pointed part. 
     More specifically, the cushioning elements  20  are arranged in the sole  12  substantially along a non-rectilinear line  40 . 
     According to a version of the present invention, such non-rectilinear line is the line on which the weight of a person is transferred during walking, i.e. along the so-called podalic line  40 , illustrated as an example in  FIG. 28 , in a manner such that, sequentially from the heel towards the metatarsus, the cushioning elements  20  are compressed by the foot during walking. 
     In such a manner, micro-traumas are prevented and walking is much more comfortable due to the cushioning effect of the elements  20 . 
     Due to the specific shapes and different sizes of the cushioning elements  20 , it is possible to obtain, with a few elements, predetermined lines such as the podalic line  40 . 
       FIG. 2  shows another sole  50 , comprising a greater number of cushioning elements  20 , and a different arrangement and orientation thereof. Such sole  50  can be provided for a more athletic shoe, adapted for supporting higher, even more dynamic loads. 
     The size, positioning and number of base cushioning elements in addition to characterizing the shoe type, whether athletic, leisure or street shoes, also defines the gender of the shoe itself: man, woman or child. It must also be observed that the cushioning elements  20  of the sole  50  are of three different sizes, all with substantially similar geometries. The cushioning element  20  of smaller size, also illustrated in the sole of  FIG. 1 , has a simplified geometry as will be better explained below. 
     In  FIG. 3 , a cushioning element of greater size in capsule form  20  is illustrated in detail; in  FIG. 4  the section of the capsule of  FIG. 3  is illustrated, while  FIGS. 5 and 6  illustrate sections of other capsules of smaller size and/or for smaller loads. 
     The section of the capsule  20  has a bottom wall  26  which forms longitudinal folds  24  which are extended over the entire body of the capsule, from the pointed part towards the wider part. 
     The folds  24  define a certain number of chambers, e.g. three inner chambers  27 ,  28 ,  29  in communication with each other, so that the gel or the incompressible material of similar type can be moved following compression from one chamber to the other and/or enlarge the chambers by forcing the folds  24  outward and/or to the side, i.e. towards the ground and/or towards the sides of the shoe, improving the body load division effect during ground impact. 
     The wall  26  defines a lower abutment surface  22  for the capsule  20  substantially formed by the outward bending around the folds  24 . 
     The capsules  20  shown in  FIGS. 3-6  have two folds  24  and three chambers  27 ,  28  and  29 , while the smaller-size capsule shown in the sole of FIGS.  1  and  2 —and not shown in the section figures—has a single fold  24  and two chambers. The simplification is due to the smaller size and to the lower load absorption needs of this capsule. 
     The wall  26  also comprises inserts  30  made of different material from that which forms the wall  26 . By means of the inserts  30 , which can be constructed in fairly rigid material with respect to that of the wall  26 , it is possible to adjust and vary the dynamic response of the capsule  20 . 
     Furthermore, by selecting the material of the inserts  30  with suitable friction coefficient, it is also possible to increase the overall ground friction of the shoe. 
     The cushioning elements according to the present invention can comprise a covering made of thermoplastic material, e.g. thermoplastic polyurethane. The covering is then filled with the gel, or with the incompressible material of similar type, and then welded, e.g. by means of an ultrasound procedure. 
     The high friction coefficient material of the inserts can comprise an elastomer of natural or synthetic origin, or even thermoplastic elastomers or mixtures of these elastomers. 
     Another to other versions of the present invention illustrated in  FIGS. 4 and 5 , one or more inserts  30  can have a head or convexity  32  projecting towards the interior of the capsule  20  inside the chambers. 
     The head  32  can be fairly significant and has the function of end stop or stop pad against the upper inner surface  34  of the capsule  20 , stopping the contraction of the latter when it is compressed by the weight of the foot. 
       FIGS. 4-6  illustrate the insert  30 , with different heights of the head  32 , with zero height limit ( FIG. 6 ); such heights are also a function of the load to be supported, as provided for the capsule. 
     Hence, for example, the greater-size capsule with more significant head  32  can be provided for men&#39;s footwear, or for the largest shoe sizes; the capsule with intermediate size, with head  32  of intermediate height, can be provided for women&#39;s footwear, or for intermediate shoe sizes; and finally the smaller-size capsule with zero-height head  32  can be provided for children, or for the smallest shoe sizes. 
       FIG. 7  shows another sole  60  equipped with cushioning elements  62 , with drop font and with different size and orientation. 
     They are arranged at different points of the podalic line, and they do not have folds: they are constituted by a flat or curved outer wall  64  in which an insert  66  is inserted, with the same concept described for the other inserts  30  of the capsules  20  of  FIGS. 3-6 . 
     In  FIG. 9 , another arrangement embodiment is shown of the cushioning elements comprising drop-form capsules  20  in a sole  12  of a shoe  10 . 
     In such sole  12 , it can be observed that at least one cushioning element  20  is positioned near the heel of the user, at least another cushioning element  20  of smaller size than the first element is positioned near the first metatarsus, and at least a further cushioning element  20 , still of smaller size than the first element, is positioned near the last metatarsus. 
     It is also observed that in such sole  12 , the capsule  20  in the zone of the heel is preferably asymmetric, and in particular it is positioned, in an asymmetric manner, in the normal impact zone of the foot with the ground. 
     In  FIGS. 10-27 , other embodiments of other arrangements and orientation of the capsules  20  in shoe soles are illustrated. The capsules  20  can be with or without folds  24  and the inserts  30  can be differently designed. 
     For example, the capsules  20  can have different sizes and shapes: triangular, trapezoidal, rhomboid, arrow etc. Due to these different characteristics, it is therefore possible to adjust and vary the dynamic response and the comfort of the shoe, always considering that the preferred form is asymmetric in order to better favor the absorption of the load in the zone of the heel and the metatarsus. 
     The series of base cushioning elements  20  with geometrically similar shapes have different sizes with respect to each other. The base cushioning elements are adapted to achieve a modular system formed by capsules  20 , and according to that illustrated in the above-described embodiments. 
     Such capsules  20 , due to the different geometric shapes and sizes, can be inserted in the soles of shoes with arrangements and orientations adapted to define predetermined lines, and in particular they can define the line on which the weight of a person is transferred during walking. 
     With this modular system, by means of a few cushioning capsules  20 , which constitute the base elements, i.e. the modules of the system, it is possible to adjust and vary the comfort and the dynamic response of the shoe. 
     In  FIG. 8 , another version of the present invention is illustrated in which, inside the shoe  10 , another capsule  70  is present. This capsule  70  is substantially similar to the capsule  20  present in the sole  12 ,  50 ,  60 , and is with or without the inserts  30 ; only the latter version without inserts  30  is illustrated in  FIG. 8 . 
     The inner capsule  70  can be arranged substantially superimposed at an outer capsule  20 , as illustrated in  FIG. 8 , or it can be arranged in a different manner, e.g. partially superimposed or in a different position with respect to the outer capsule  20  (the latter two versions are not illustrated). 
     In this manner, one obtains a greater pliability of the sole or of the insole and thus a greater overall comfort of the shoe. 
     The present invention thus conceived is susceptible to numerous modifications and variations, all coming within the protective scope of the claims.