Patent Publication Number: US-2023157403-A1

Title: Mechanical lock sole structure for braided footwear

Description:
CLAIM OF PRIORITY 
     This application is a Divisional application of U.S. Non-Provisional patent application Ser. No. 17/172,531 (filed on Feb. 10, 2021 and to be issued on Jan. 10, 2023 as U.S. Pat. No. 11,547,171), which claims priority to U.S. Non-Provisional patent application Ser. No. 15/993,105 (filed on May 30, 2018 and granted on Mar. 23, 2021 as U.S. Pat. No. 10,952,490), which claims priority to U.S. Provisional Patent Application No. 62/512,557 (filed May 30, 2017). The entireties of all of the above applications and patents are incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to articles of footwear, and in particular, a mechanical lock sole structure for a braided article of footwear. 
     BACKGROUND 
     Traditional shoes are often made from textiles or materials that have uppers that are cut to a desired shape and stitched together. Newer methods also now include forming shoe uppers from a knitted textile. Still newer methods involve braiding a tubular textile for use as the shoe upper. Aspects herein relate to braiding tubular structures that in some aspects are used in articles of footwear. 
     SUMMARY 
     An article of braided footwear having a mechanical lock sole structure and a braided upper is provided. Some aspects generally include a braided upper and an integrated sole structure that mechanically engages at least a portion of the braided upper, such as a locking midsole having a bottom surface keyed with surface features that interact with a shoe bottom and/or shoe side surface of the braided upper. The integrated midsole may engage at least a portion of the braided upper by extending through a plurality of mesh-like braided apertures of the braided upper and into contact with a ground surface, providing outsole functionality in addition to midsole support. Additionally, based on engaging a perimeter of each sole surface feature with a corresponding and surrounding braid aperture, in some aspects, an interlocked sole and braided upper may become stabilized into a secured/keyed position within the braided upper. 
     This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
       Illustrative aspects of the present invention are described in detail below with reference to the attached drawing figures, which are incorporated by reference herein and wherein: 
         FIG.  1    depicts a schematic view of an exemplary braiding machine, in accordance with aspects herein; 
         FIG.  2    depicts a schematic top view of an exemplary braiding machine, illustrating the carriages and rotor metals, in accordance with aspects herein; 
         FIG.  3    depicts a view similar to  FIG.  2   , but with the rotor metals moving the carriages, in accordance with aspects herein; 
         FIG.  4    depicts a view similar to  FIG.  3   , but showing the completion of the exemplary movement of  FIG.  3   , in accordance with aspects herein; 
         FIG.  5    depicts a perspective view of an exemplary midsole, in accordance with aspects herein; 
         FIG.  6    depicts a side perspective view of an exemplary braided upper comprising a tubular braided structure and a plurality of apertures, in accordance with aspects herein; 
         FIG.  7    depicts a side perspective view of an exemplary braided article of footwear, in accordance with aspects herein; 
         FIG.  8    depicts a bottom view of the exemplary braided article of footwear of  FIG.  7   , in accordance with aspects herein; 
         FIG.  9 A  depicts a rear view of the exemplary braided article of footwear of  FIG.  7    at the heel end, in accordance with aspects herein; 
         FIG.  9 B  depicts a cross-sectional view of  FIG.  9 A , in accordance with aspects herein; 
         FIG.  10    depicts a close-up view of a portion of the exemplary braided article of footwear of  FIG.  7   , in accordance with aspects herein; 
         FIG.  11 A  depicts a perspective view of the exemplary braided article of footwear of  FIG.  7    with a sprayed outsole covering a portion of the midsole and bottom surface of the braided upper, in accordance with aspects herein; 
         FIG.  11 B  depicts a cross-section view of  FIG.  11 A  taken at cut line  11 B- 11 B, in accordance with aspects herein; 
         FIG.  12 A  depicts a side-view of an exemplary braided article of footwear, in accordance with aspects herein; 
         FIG.  12 B  depicts a perspective view of the exemplary braided article of footwear of  FIG.  12 A , in accordance with aspects herein; 
         FIG.  13    depicts a bottom view of the exemplary braided article of footwear of  FIG.  12 A , in accordance with aspects herein; 
         FIGS.  14 A and  14 B  depict cross-sectional views of  FIG.  13   , in accordance with aspects herein; 
         FIG.  15    depicts a side view of an exemplary braided article of footwear, in accordance with aspects herein; and 
         FIG.  16    depicts a bottom view of the braided article of footwear of  FIG.  15   , in accordance with aspects herein. 
     
    
    
     DETAILED DESCRIPTION 
     The subject matter of the present invention is described with specificity herein to meet statutory requirements. However, the description itself is not intended to limit the scope of this patent. 
     Generally, articles of footwear have two major components, an upper that provides the enclosure for receiving the foot and a sole secured to the upper. The upper may be adjustable using laces, hook-and-loop fasteners, or other devices to secure the shoe to the foot. The upper may further be engineered to provide the appropriate type of protection to the foot and to maximize the wearer&#39;s comfort. A sole may comprise a midsole and an outsole. The outsole portion usually has primary contact with the ground and may be designed to absorb shock as the footwear contacts the ground or other surfaces. 
     In the aspects discussed herein, the article of footwear is in the form of different athletic shoes. However, in some other aspects, the provisions discussed herein for the braided article of footwear could be incorporated into various other kinds of footwear, including, but not limited to, basketball shoes, hiking boots, soccer shoes, football shoes, sneakers, running shoes, cross-training shoes, and other types of footwear. Moreover, in some aspects, the provisions discussed herein for an article of footwear could be incorporated into various other kinds of non-sports related footwear, including, but not limited to slippers, sandals, high heeled footwear, loafers, as well as other kinds of footwear. 
     At a high level, aspects herein are directed to a braided article of footwear that comprises a flexible shoe sole that is secured to the braided upper. A braided upper is defined as a unitary braid structure manufactured using a braiding technique. Braiding is the process of interlacing or interweaving three or more yarns diagonally to a product axis in order to obtain a thicker, wider or stronger product or in order to cover (overbraid) some profile. Interlacing diagonally means that the yarns make an angle with the product axis, which can be between 1° and 89° but is usually in the range of 30°-80°. This angle is called the braiding angle. Braids can be linear products (ropes), hollow tubular shells or solid structures (one, two or three-dimensional textiles) with constant or variable cross-section, and of closed or open appearance. 
     As used herein, the yarns used for braiding may be formed of different materials having different properties. The properties that a particular yarn will impart to an area of a braided component partially depend upon the materials that form the yarn. Cotton, for example, provides a softer product, natural aesthetics, and biodegradability. Elastane and stretch polyester each provide substantial stretch and recovery, with stretch polyester also providing recyclability. Rayon provides high luster and moisture absorption. Wool also provides high moisture absorption, in addition to insulating properties and biodegradability. Nylon is a durable and abrasion-resistant material with relatively high strength. Polyester is a hydrophobic material that also provides relatively high durability. In addition to materials, other aspects of the yarn selected for formation of a braided component may affect the properties of the braided component. For example, a yarn may be a monofilament or a multifilament. The yarn may also include separate filaments that are each formed of different materials. In addition, the yarn may include filaments that are each formed of two or more different materials, such as a bicomponent yarn with filaments having a sheath-core configuration or two halves formed of different materials. 
     By using a braiding technique, the articles of footwear may be engineered with specific features tailored to a particular athletic or recreational activity and are characterized by close containment over the wearer&#39;s foot. Different regions of the braided upper may have different braided configurations. For example, higher braid densities may be used in specific areas of the footwear to provide additional structural support or compression. The different braid densities are incorporated with one another to form a seamless braided upper. The term braided density refers to the number and/or concentration of the particular yarn used in braiding the different regions and is measured by the number of yarn interlacings per unit area. Additionally, yarns of different material may be incorporated in different regions of the braided upper to provide specific properties to the footwear in those areas. For example, yarns made of material with a greater tensile strength may be used in sections of the footwear that undergo higher stress during a specific activity. Softer and more pliable yarns may be used in sections of the footwear that are not subject to high stress, to provide a more comfortable and closely-fitting upper in those sections. Further, the different braid densities may vary in structural properties such as the number of yarns in the braid, the diameter of one or more yarns of the braid, the density of the yarns, and the material properties of the yarns such as elasticity, rigidity, tensile strength, compressibility, and other material properties. 
     The braided upper formed using a braiding technique is secured to the sole structure which extends between the foot and the ground when the article is worn. In different aspects, the sole structure may include different components. For example, a sole structure may include a midsole only or a midsole and an outsole. Sole structures may also provide one or more functions for the article. For example, a sole structure may be configured to provide traction for an article when worn. Additionally, the midsole may include a polymer foam material that attenuates ground reaction forces when compressed between the foot and the ground during walking, running, or other ambulatory activities. The midsole may also be made of relatively soft material to provide cushioning. The outsole is generally made of harder, more abrasion-resistant material such as rubber or EVA. The outsole is secured to a lower surface of the midsole and provides a ground-engaging portion of the sole structure formed from a durable and wear-resistant material, such as rubber. 
     The figures depict articles of footwear with braided uppers comprising a braided tubular structure with a plurality of apertures on the bottom surface of the braided upper. The braided upper extends beneath the foot of the wearer, thereby providing 360-degree containment around the bottom of the foot. The midsole comprises a plurality of protruding studs that are keyed to receive the plurality of apertures of the braided upper. In other words, the plurality of apertures of the braided upper and the plurality of protruding studs are configured so that the plurality of protruding studs fit through the plurality of apertures and extend below the bottom surface of the plurality of apertures of the braided upper. When the plurality of studs of the midsole receive the plurality of apertures of the braided upper, at least one of the plurality of apertures encircles the plurality of protruding studs to provide 360-degree containment. Additionally, each of the plurality of studs comprises at least one ground-contact outer surface that extends below the bottom surface of the braided upper. The at least one ground-contact outer surface comprises a non-compressible material that maintains a primary configuration upon ground contact. Further, the plurality of protruding studs of the midsole may comprise all or a portion of the midsole. 
     In some aspects, a mechanical lock sole structure may include an interlocking midsole having one or more surface features keyed to a sole portion of a braided upper. For example, a midsole may include multiple protruding studs along a bottom surface of the midsole. In further aspects, the midsole material may include various materials that provide cushioning, such as polyurethane foam, compression-molded EVA, leather or polyurethane. 
     In one aspect, a uniform size, spacing, height, and/or dimension may be associated with the plurality of protruding studs on the midsole. In other aspects, the plurality of protruding studs may vary in size, spacing, height, dimension, location, and/or configuration on the midsole depending on the type of footwear. For example, in certain athletic shoes, the plurality of protruding studs may be located in a specific pattern to aid in directional movement when worn and may consist of one or more shapes. The plurality of apertures in the braided upper structure are keyed to mate to the plurality of protruding studs and may correspond to the circumference of a particular protruding stud. For example, a hexagonal protruding stud extending from a bottom surface of the midsole may correspond to a hexagonal aperture in the braid structure. 
     In one aspect, the midsole may be pre-molded with the plurality of protruding studs prior to being received by the plurality of apertures of the braided upper. In other aspects, the midsole compromises a co-molded midsole associated with the braided upper during the three dimensional assembly processes, wherein the co-molded midsole comprises a flexible joining with the braided upper. In yet another aspect, the braided article of footwear comprises a sprayed outsole. The sprayed outsole comprises a spray component which is applied to both the plurality of studs extending below the bottom surface of the braided upper and the bottom surface of the braided upper. In this aspect, the outsole is sprayed onto the plurality of studs and the bottom surface of the braided upper after the outsole and bottom surface of the braided upper are “locked” together. The spray component applied may, for example, comprise a sprayed polyurethane, which provides an additional covering to the article of footwear and strengthens the flexible joining of the midsole and braided upper. 
     In yet another aspect, the braided upper comprises a tubular braided structure and a plurality of apertures and the midsole comprises a planar surface comprising a plurality of braid-receiving features that mate to the plurality of apertures. The braided upper and midsole are secured together based on the plurality of apertures coupling to the plurality of braid receiving features. In some aspects, an outsole may also be coupled to the braided upper and midsole. 
     In yet another aspect, the braided article of footwear comprises a braided upper and a midsole. The braided upper comprises a tubular braided structure and a plurality of apertures. The plurality of apertures are keyed to surround the plurality of protruding studs of a midsole when secured together to provide 360-degree containment of the protruding studs. 
     As stated above, braided structures can be formed as tubular braids on a braiding machine, such as a radial, axial or lace braiding machine. One example of a lace braiding machine can be found in Ichikawa, EP 1 486 601, granted May 9, 2007, entitled “Torchon Lace Machine” and EP No. 2 657 384, published Oct. 30, 2013, entitled “Torchon Lace Machine,” the entirety of which are hereby incorporated by reference. The upper portion of an exemplary braiding machine  10  is shown in  FIG.  1   . Braiding machine  10  includes a plurality of spools  12 . In some aspects, the spools  12  carry the yarn  14  selected for braiding. The yarns  14  from individual spools  12  are selectively interlaced or intertwined with one another by the braiding machine  10 . This interlacing or intertwining of strands forms a braided structure  16 , as further described below. Each of the spools  12  is supported and constrained by a track  18  about the circumference of the braiding machine  10 . Each spool  12  has a tensioner  20  (shown schematically in  FIG.  1   ) that operates, along with a roller  22 , to maintain a desired tension in the yarns  14  and the braided structure  16 . As the yarns  14  extend upwardly, they pass through a braid ring  24  that is generally considered the braiding point. The braiding point is defined as the point or area where yarns  14  consolidate to form braided structure  16 . At or near braid ring  24 , the distance between yarns  14  from different spools  12  diminishes. As the distance between yarns  14  is reduced, the yarns  14  intermesh or braid with one another in a tighter fashion and are pulled linearly by roller  22 . 
     As best seen in  FIGS.  2  and  3   , each spool  12  is carried and supported by a carriage  26 . Each spool  12  is movable about the circumference of the track  18  by rotor metals  28 . As described on the Torchon Lace Machine referenced previously, and disclosed in EP 1 486 601, each of the rotor metals  28  can be moved clockwise or counterclockwise. In contrast to radial braiding machines or fully non-jacquard machines, in a lace braiding machine, each rotor metal is not intermeshed with the adjacent rotor metal. Instead, each rotor metal  28  may be selectively independently movable. As can be seen by comparing  FIG.  3    to  FIG.  4   , as the rotor metals  28  rotate, they move the carriages  26 , and thus the spools  12  supported on the carriages  26  by moving them about the circumference of the track  18 . The braiding machine  10  is programmable such that the individual rotor metals  28  rotate the carriages  26 , and thus the spools  12  to move them about the circumference of the track  18 . As an individual spool  12  moves relative to an adjacent spool  12 , the yarns  14  carried on the spools  12  interweave to create a desired braid pattern. The movement of spools  12  may be pre-programmed to form particular shapes, designs, and thread densities of a braided component or portions of a braided component. By varying the rotation and location of individual spools  12 , various braid configurations may be formed. Such an exemplary braiding machine may form intricate braid configurations including both jacquard and non-jacquard braid configurations or geometries. Such configurations and geometries offer design possibilities beyond those offered by other textiles, such as knitting. 
     In some aspects, the size of braiding machine  10  may be varied. It should be understood that the braiding machine  10  shown and described is for illustrative purposes only. In some aspects, braiding machine  10  may be able to accept  144  carriages, although other sizes of braiding machines, carrying different numbers of carriages and spools is possible and is within the scope of this disclosure. By varying the number of carriages and spools within a braiding machine, the density of the braided structure as well as the size of the braided component may be altered. 
     Turning now to  FIGS.  5 - 10   , aspects of a mechanical lock sole structure of a braided article of footwear include a braided upper  104  ( FIG.  6   ) and a midsole  100  ( FIG.  5   ) that are coupled together to form a braided article of footwear  126  ( FIG.  7   ). As seen in  FIG.  5   , the midsole  100  includes a plurality of spaced, protruding studs  102  extending from a bottom surface  101  of the midsole  100 . The protruding studs  102  may vary in location, spacing, shape, height, and width, depending on the article of footwear. For example, as shown in  FIG.  5   , the protruding studs  102  are of a generally partial spherical shape extending from the bottom surface  101 . However, in an alternative aspect such as a soccer cleat, the geometry of the protruding studs  102  on the midsole  100  may be conical instead to help with multi-directional movements. Further, the midsole  100  may include more than one geometry of protruding studs  102 . For example, the bottom surface  101  of the midsole  100  for soccer cleats may include conical, chevron (inverted V shape), and other geometries of protruding studs  102 . 
     The protruding studs  102  extend a particular distance  103  below the midsole  100  depending on the location of the stud, shape of the stud, and type of article of footwear. In some aspects, each protruding stud  102  has at least one ground-contact outer surface  132 . It is also contemplated that the protruding studs  102  may cover all or a portion of the bottom surface  101  of the midsole  100 . In  FIG.  5   , the protruding studs  102  are uniformly located across the bottom surface  101  of the midsole  100 . However, the protruding studs  102  may be located in any location or configuration across all or portions of the bottom surface  101  of the midsole  100 . In some aspects, the protruding studs  102  are pre-molded or co-molded with the midsole  100 . 
       FIG.  6    depicts a side perspective view of the braided upper  104  of the braided article of footwear  126 . The braided upper  104  comprises a tubular braided structure  114  with an ankle opening  112 , a toe end  108  opposite a heel end  110 , an internal cavity  116 , and a bottom surface  118 . The tubular braided structure  114  has a braid configuration in at least one area defining a plurality of apertures  106  that correspond in location, size, and shape to the protruding studs  102  of the midsole  100  depicted in  FIG.  5   . 
     The tubular braided structure  114  is a unitary braided structure when formed as a one-piece element through a braiding process, which forms the various features and structures of the braided component without the need for significant additional manufacturing steps or processes. The density and composition of the braiding of the braided upper  104  may vary from the top portion  120  of the braided upper  104  to the bottom surface  118  of the braided upper  104 , resulting in zonal braiding where the density of the braid changes in different areas of the braided upper or from zone-to-zone. The braided upper  104  depicted in  FIG.  6    is merely one example of a braid pattern. However, it is contemplated that the braided upper may comprise various braided configurations based on the type of footwear. For example, in  FIG.  6   , the braid configuration comprises a dense braid on the top portion of the braided upper at  120 . The braid then transitions to a slightly wider braid  122  on the sides of the braided upper, and further transitions to an even wider braid  124  on the bottom surface  118  of the braided upper  104  where the plurality of apertures  106  are located. While the density of the braiding may vary in different areas of the braided upper, the braided upper  104  is one continuous tubular braided structure  114  as depicted in  FIG.  6   . The varying density of the tubular braided structure  114  may be engineered to provide the appropriate level of structural stability, support, durability, and comfort. 
       FIGS.  7  and  8    illustrate the combination of the midsole  100  and the braided upper  104 , forming the braided article of footwear  126 . As shown in  FIGS.  7 - 10   , the midsole  100  from  FIG.  5    is in engagement with the braided upper  104  from  FIG.  6   . In this condition, the protruding studs  102  of midsole  100  extend though the defined apertures  106  of braided upper  104 . When the midsole  100  engages the braided upper  104 , the yarns of the braid configuration defining the apertures  106  provide 360-degree containment around the corresponding protruding studs  102 , as best seen in  FIG.  10   . This containment “locks” the braided upper  104  into the midsole  100 . 
       FIG.  8    illustrates a bottom perspective view of the braided article of footwear  126  of  FIG.  7   . As seen in  FIG.  8   , in some aspects the braided upper  104  has a tighter, denser braid configuration at  122  and a less dense braid configuration at  124 . The wider braiding found at the bottom surface  118  of the braided upper  104  creates, at least in part, the apertures  106  through which protruding studs  102  extend to provide 360-degree containment. 
       FIG.  9 A  depicts a rear view of the braided article of footwear  126  at the heel end  110 .  FIG.  9 B  is a cross-section of  FIG.  9 A , showing the midsole  100  and the protruding studs  102  extending through the bottom surface  118  of the braided upper  104 . As shown in  FIGS.  9 A and  9 B , in some aspects, at least a portion of the braided upper  104  defined by the apertures  106  abuts a circumference of each of the plurality of protruding studs  102  as seen at  140  and  146 . The relationship between the apertures  106  of the braided upper  104  and the protruding studs  102  of the midsole  100  is also shown in the enlarged view of  FIG.  10   . 
       FIGS.  11 A- 11 B  illustrate an additional aspect in which an outsole  200  is applied to the bottom surface  118  of the braided upper  104  and the protruding studs  102  of the midsole  100 . In one aspect, the outsole  200  comprises a component  150  that is applied to both the protruding studs  102  extending below the bottom surface  118  of the braided upper  104 , and the bottom surface  118  of the braided upper  104 . In an exemplary aspect, component  150  can be applied as a spray. As described above, the component  150  may comprise a polyurethane material or any other suitable component for an outsole.  FIG.  11 B  is a cross-section view of  FIG.  11 A  and depicts the outsole  200  that has been applied to both the protruding studs  102  extending from the bottom surface  101  of the midsole  100  and the bottom surface  118  of the braided upper  104 . 
       FIGS.  12 - 14    illustrate additional aspects of a mechanical lock sole structure of a braided article of footwear.  FIG.  12 A  illustrates a side perspective view of a braided article of footwear  300 , shown without an outsole. In this configuration, a braided upper  302  comprises a tubular braided structure  304  that defines a plurality of apertures  306 . For clarity, the braid configuration of braided upper  302  is shown schematically. It should be understood that any number of braid configurations could be used. At least a portion of the braided upper  302  has a braid configuration defining apertures  306 . Apertures  306  are shown in a generally diamond shape, but could be any of a number of other shapes as well. The braided upper  302  is shown in  FIG.  12 A  in engagement with a midsole  320 , which is further described with respect to  FIG.  12 B . As best seen in  FIG.  12 B , the midsole  320  extends from the top  305  to a bottom surface  307 , spaced from one another by a side wall  309 . Midsole  320  includes a number of spaced apart braid receiving features  312 . In one aspect, braid receiving features  312  are formed as grooves extending into the midsole  320 . As shown in  FIGS.  12 A and  12 B , the braid receiving features  312  can be formed on the bottom surface  307  as well as the side wall  309 . 
       FIG.  13    illustrates the bottom view of the braided article of footwear of  FIG.  12 A . As can be seen in  FIGS.  12 A and  13   , the apertures  306  of the braided upper  302  are positioned to correspond with braid receiving features  312  on midsole  320 . When midsole  320  is placed within the braided upper  302 , the braid receiving features  312  receive, in at least some locations, the yarn of the braided upper  302 , such that the apertures  306  mate with the braid receiving features  312 . In this construction, the braided upper  302  is keyed into the midsole  320 . 
       FIG.  14 B  illustrates a cross-section of  FIG.  13   . The braided upper  302  extends around the midsole  320 . In addition, portions of the braided upper  302 , namely the braided structure around apertures  306 , fit within at least some of the braid receiving features  312 . This may include, for example, braid receiving features  312  on either the bottom surface  307  or the side walls  309 , or both.  FIG.  14 B  also depicts an outsole  322  that can be coupled to the combined braided upper  302  and midsole  320 , in some aspects.  FIG.  14 A  illustrates the structure of  FIG.  14 B , with the outsole  322  coupled to the midsole  320  and braided upper  302 . 
       FIGS.  15 - 16    illustrate another aspect of the mechanical lock structure of a braided article of footwear  406 . Like the aspects discussed above with respect to  FIGS.  12 - 14   , the braided article of footwear  406  includes a braided upper  400  and a midsole  402 . In this aspect, the midsole  402  has a plurality of protruding studs  404  that are somewhat similar to those discussed with respect to  FIGS.  5 - 10   .  FIG.  15    depicts a side view of the braided article of footwear  406 . The braided upper  400  comprises a tubular braided structure  408  which receives the midsole  402  and the corresponding protruding studs  404 . Like  FIGS.  12 - 14   , the braided upper  400  may be braided with apertures  403  that interact with braid receiving features  405 . 
       FIG.  16    illustrates the bottom view of the braided article of footwear of  FIG.  15   . The bottom surface  410  of the braided upper  400  has a braid design that is configured to engage the protruding studs  404  to provide 360-degree containment. For example, yarns  412 ,  414 ,  416 ,  418  and  420  on the bottom surface  410  of the braided upper  400 , are configured to encircle protruding stud  422  and provide 360-degree containment of the protruding stud  422 . In this aspect, the plurality of protruding studs  404  depicted are chevron shaped and configured in a specific pattern for the type of footwear shown. However, the plurality of protruding studs  404  may vary in shape and height with each protruding stud  404  maintaining a ground-contact surface. 
     From the foregoing, it will be seen that this invention is one well adapted to attain all the ends and objects hereinabove set forth together with other advantages that are obvious and are inherent to the structure. It will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations. This is contemplated by and is within the scope of the claims. 
     While specific elements are discussed in connection to one another, it is understood that any element provided herein is contemplated as being combinable with any other elements regardless of explicit provision of the same while still being within the scope provided herein. Since many possible aspects may be made of the disclosure without departing from the scope thereof, it is to be understood that all matter herein set forth or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense.